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Int. J. Mol. Sci., Volume 13, Issue 2 (February 2012) – 80 articles , Pages 1269-2534

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246 KiB  
Article
Chemical Reaction of Soybean Flavonoids with DNA: A Computational Study Using the Implicit Solvent Model
by Hassan H. Abdallah, Janez Mavri, Matej Repič, Vannajan Sanghiran Lee and Habibah A. Wahab
Int. J. Mol. Sci. 2012, 13(2), 1269-1283; https://doi.org/10.3390/ijms13021269 - 25 Jan 2012
Cited by 6 | Viewed by 7524
Abstract
Genistein, daidzein, glycitein and quercetin are flavonoids present in soybean and other vegetables in high amounts. These flavonoids can be metabolically converted to more active forms, which may react with guanine in the DNA to form complexes and can lead to DNA depurination. [...] Read more.
Genistein, daidzein, glycitein and quercetin are flavonoids present in soybean and other vegetables in high amounts. These flavonoids can be metabolically converted to more active forms, which may react with guanine in the DNA to form complexes and can lead to DNA depurination. We assumed two ultimate carcinogen forms of each of these flavonoids, diol epoxide form and diketone form. Density functional theory (DFT) and Hartree-Fock (HF) methods were used to study the reaction thermodynamics between active forms of flavonoids and DNA guanine. Solvent reaction field method of Tomasi and co-workers and the Langevin dipoles method of Florian and Warshel were used to calculate the hydration free energies. Activation free energy for each reaction was estimated using the linear free energy relation. Our calculations show that diol epoxide forms of flavonoids are more reactive than the corresponding diketone forms and are hence more likely flavonoid ultimate carcinogens. Genistein, daidzein and glycitein show comparable reactivity while quercetin is less reactive toward DNA. Full article
(This article belongs to the Section Physical Chemistry, Theoretical and Computational Chemistry)
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309 KiB  
Article
Imidazolines as Non-Classical Bioisosteres of N-Acyl homoserine lactones and Quorum Sensing Inhibitors
by Alicia Reyes-Arellano, Alejandro Bucio-Cano, Mabel Montenegro-Sustaita, Everardo Curiel-Quesada and Héctor Salgado-Zamora
Int. J. Mol. Sci. 2012, 13(2), 1284-1299; https://doi.org/10.3390/ijms13021284 - 25 Jan 2012
Cited by 10 | Viewed by 8045
Abstract
A series of selected 2-substituted imidazolines were synthesized in moderate to excellent yields by a modification of protocols reported in the literature. They were evaluated as potential non-classical bioisosteres of AHL with the aim of counteracting bacterial pathogenicity. Imidazolines 18a, 18e and [...] Read more.
A series of selected 2-substituted imidazolines were synthesized in moderate to excellent yields by a modification of protocols reported in the literature. They were evaluated as potential non-classical bioisosteres of AHL with the aim of counteracting bacterial pathogenicity. Imidazolines 18a, 18e and 18f at various concentrations reduced the violacein production by Chromobacterium violaceum, suggesting an anti-quorum sensing profile against Gram-negative bacteria. Imidazoline 18b did not affect the production of violacein, but had a bacteriostatic effect at 100 µM and a bactericidal effect at 1 mM. Imidazoline 18a bearing a hexyl phenoxy moiety was the most active compound of the series, rendering a 72% inhibitory effect of quorum sensing at 100 µM. Imidazoline 18f bearing a phenyl nonamide substituent presented an inhibitory effect on quorum sensing at a very low concentration (1 nM), with a reduction percentage of 28%. This compound showed an irregular performance, decreasing inhibition at concentrations higher than 10 µM, until reaching 100 µM, at which concentration it increased the inhibitory effect with a 49% reduction percentage. When evaluated on Serratia marcescens, compound 18f inhibited the production of prodigiosin by 40% at 100 μM. Full article
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258 KiB  
Article
Expression Analysis of MYC Genes from Tamarix hispida in Response to Different Abiotic Stresses
by Xiaoyu Ji, Yucheng Wang and Guifeng Liu
Int. J. Mol. Sci. 2012, 13(2), 1300-1313; https://doi.org/10.3390/ijms13021300 - 25 Jan 2012
Cited by 10 | Viewed by 7802
Abstract
The MYC genes are a group of transcription factors containing both bHLH and ZIP motifs that play important roles in the regulation of abscisic acid (ABA)-responsive genes. In the present study, to investigate the roles of MYC genes under NaCl, osmotic and ABA [...] Read more.
The MYC genes are a group of transcription factors containing both bHLH and ZIP motifs that play important roles in the regulation of abscisic acid (ABA)-responsive genes. In the present study, to investigate the roles of MYC genes under NaCl, osmotic and ABA stress conditions, nine MYC genes were cloned from Tamarix hispida. Real-time reverse-transcriptase (RT)-PCR showed that all nine MYC genes were expressed in root, stem and leaf tissues, but that the levels of the transcripts of these genes in the various tissues differed notably. The MYC genes were highly induced in the roots in response to ABA, NaCl and osmotic stresses after 3 h; however, in the stem and leaf tissues, MYC genes were highly induced only when exposed to these stresses for 6 h. In addition, most of these MYC genes were highly expressed in roots in comparison with stems and leaves. Furthermore, the MYC genes were more highly induced in roots than in stem and leaf tissues, indicating that these genes may play roles in stress responses mainly in the roots rather than the stems and leaves. The results of this present study suggest that MYCs are involved in salt and osmotic stress tolerances and are controlled by the ABA signal transduction pathway. Full article
(This article belongs to the Special Issue Advances in Molecular Plant Biology)
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340 KiB  
Article
Serine Hydroxymethyltransferase from the Cold Adapted Microorganism Psychromonas ingrahamii: A Low Temperature Active Enzyme with Broad Substrate Specificity
by Sebastiana Angelaccio, Rita Florio, Valerio Consalvi, Guido Festa and Stefano Pascarella
Int. J. Mol. Sci. 2012, 13(2), 1314-1326; https://doi.org/10.3390/ijms13021314 - 25 Jan 2012
Cited by 23 | Viewed by 7366
Abstract
Serine hydroxymethyltransferase from the psychrophilic microorganism Psychromonas ingrahamii was expressed in Escherichia coli and purified as a His-tag fusion protein. The enzyme was characterized with respect to its spectroscopic, catalytic, and thermodynamic properties. The properties of the psychrophilic enzyme have been contrasted with [...] Read more.
Serine hydroxymethyltransferase from the psychrophilic microorganism Psychromonas ingrahamii was expressed in Escherichia coli and purified as a His-tag fusion protein. The enzyme was characterized with respect to its spectroscopic, catalytic, and thermodynamic properties. The properties of the psychrophilic enzyme have been contrasted with the characteristics of the homologous counterpart from E. coli, which has been structurally and functionally characterized in depth and with which it shares 75% sequence identity. Spectroscopic measures confirmed that the psychrophilic enzyme displays structural properties almost identical to those of the mesophilic counterpart. At variance, the P. ingrahamii enzyme showed decreased thermostability and high specific activity at low temperature, both of which are typical features of cold adapted enzymes. Furthermore, it was a more efficient biocatalyst compared to E. coli serine hydroxymethyltransferase (SHMT) particularly for side reactions. Many β-hydroxy-α-amino acids are SHMT substrates and represent important compounds in the synthesis of pharmaceuticals, agrochemicals and food additives. Thanks to these attractive properties, this enzyme could have a significant potential for biotechnological applications. Full article
(This article belongs to the Section Biochemistry)
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958 KiB  
Article
Effect of Fiber Esterification on Fundamental Properties of Oil Palm Empty Fruit Bunch Fiber/Poly(butylene adipate-co-terephthalate) Biocomposites
by Samira Siyamak, Nor Azowa Ibrahim, Sanaz Abdolmohammadi, Wan Md Zin Wan Yunus and Mohamad Zaki AB Rahman
Int. J. Mol. Sci. 2012, 13(2), 1327-1346; https://doi.org/10.3390/ijms13021327 - 27 Jan 2012
Cited by 45 | Viewed by 8685
Abstract
A new class of biocomposites based on oil palm empty fruit bunch fiber and poly(butylene adipate-co-terephthalate) (PBAT), which is a biodegradable aliphatic aromatic co-polyester, were prepared using melt blending technique. The composites were prepared at various fiber contents of 10, [...] Read more.
A new class of biocomposites based on oil palm empty fruit bunch fiber and poly(butylene adipate-co-terephthalate) (PBAT), which is a biodegradable aliphatic aromatic co-polyester, were prepared using melt blending technique. The composites were prepared at various fiber contents of 10, 20, 30, 40 and 50 wt% and characterized. Chemical treatment of oil palm empty fruit bunch (EFB) fiber was successfully done by grafting succinic anhydride (SAH) onto the EFB fiber surface, and the modified fibers were obtained in two levels of grafting (low and high weight percentage gain, WPG) after 5 and 6 h of grafting. The FTIR characterization showed evidence of successful fiber esterification. The results showed that 40 wt% of fiber loading improved the tensile properties of the biocomposite. The effects of EFB fiber chemical treatments and various organic initiators content on mechanical and thermal properties and water absorption of PBAT/EFB 60/40 wt% biocomposites were also examined. The SAH-g-EFB fiber at low WPG in presence of 1 wt% of dicumyl peroxide (DCP) initiator was found to significantly enhance the tensile and flexural properties as well as water resistance of biocomposite (up to 24%) compared with those of untreated fiber reinforced composites. The thermal behavior of the composites was evaluated from thermogravimetric analysis (TGA)/differential thermogravimetric (DTG) thermograms. It was observed that, the chemical treatment has marginally improved the biocomposites’ thermal stability in presence of 1 wt% of dicumyl peroxide at the low WPG level of grafting. The improved fiber-matrix surface enhancement in the chemically treated biocomposite was confirmed by SEM analysis of the tensile fractured specimens. Full article
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1073 KiB  
Article
MetastamiRs: Non-Coding MicroRNAs Driving Cancer Invasion and Metastasis
by Cesar Lopez-Camarillo, Laurence A. Marchat, Elena Arechaga-Ocampo, Carlos Perez-Plasencia, Oscar del Moral-Hernandez, Elizabeth J. Castaneda-Ortiz and Sergio Rodriguez-Cuevas
Int. J. Mol. Sci. 2012, 13(2), 1347-1379; https://doi.org/10.3390/ijms13021347 - 27 Jan 2012
Cited by 51 | Viewed by 11414
Abstract
MicroRNAs (miRNAs) are small non-coding RNAs of ~22 nucleotides that function as negative regulators of gene expression by either inhibiting translation or inducing deadenylation-dependent degradation of target transcripts. Notably, deregulation of miRNAs expression is associated with the initiation and progression of human cancers [...] Read more.
MicroRNAs (miRNAs) are small non-coding RNAs of ~22 nucleotides that function as negative regulators of gene expression by either inhibiting translation or inducing deadenylation-dependent degradation of target transcripts. Notably, deregulation of miRNAs expression is associated with the initiation and progression of human cancers where they act as oncogenes or tumor suppressors contributing to tumorigenesis. Abnormal miRNA expression may provide potential diagnostic and prognostic tumor biomarkers and new therapeutic targets in cancer. Recently, several miRNAs have been shown to initiate invasion and metastasis by targeting multiple proteins that are major players in these cellular events, thus they have been denominated as metastamiRs. Here, we present a review of the current knowledge of miRNAs in cancer with a special focus on metastamiRs. In addition we discuss their potential use as novel specific markers for cancer progression. Full article
(This article belongs to the Special Issue Non-Coding RNAs)
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231 KiB  
Article
Compositional Variation in Sugars and Organic Acids at Different Maturity Stages in Selected Small Fruits from Pakistan
by Tahir Mahmood, Farooq Anwar, Mateen Abbas, Mary C. Boyce and Nazamid Saari
Int. J. Mol. Sci. 2012, 13(2), 1380-1392; https://doi.org/10.3390/ijms13021380 - 27 Jan 2012
Cited by 128 | Viewed by 8911
Abstract
Selected soluble sugars and organic acids were analyzed in strawberry, sweet cherry, and mulberry fruits at different ripening stages by HPLC. The amounts of fructose, glucose and sucrose were found to be: strawberry (1.79–2.86, 1.79–2.25 and 0.01–0.25 g/100 g FW), sweet cherry (0.76–2.35, [...] Read more.
Selected soluble sugars and organic acids were analyzed in strawberry, sweet cherry, and mulberry fruits at different ripening stages by HPLC. The amounts of fructose, glucose and sucrose were found to be: strawberry (1.79–2.86, 1.79–2.25 and 0.01–0.25 g/100 g FW), sweet cherry (0.76–2.35, 0.22–3.39 and 0.03–0.13 g/100 g) and mulberry (3.07–9.41, 1.53–4.95 and 0.01–0.25 g/100 g) at un-ripened to fully-ripened stages, respectively. The strawberry, sweet cherry and mulberry mainly contained tartaric, citric and ascorbic acids in the range of 16–55, 70–1934 and 11–132 mg/100 g; 2–8, 2–10 and 10–17 mg/100 g; 2–118, 139–987 and 2–305 mg/100 g at un-ripened to fully-ripened stages, respectively. Fructose and glucose were established to be the major sugars in all the tested fruit while citric and ascorbic acid were the predominant organic acids in strawberry and mulberry while tartaric acid was mainly present in sweet cherry. The tested fruits mostly showed an increase in the concentration of sugars and organic acids with ripening. Full article
(This article belongs to the Section Biochemistry)
268 KiB  
Article
Acute Oral Toxicity Evaluations of Some Zinc(II) Complexes Derived from 1-(2-Salicylaldiminoethyl)piperazine Schiff Bases in Rats
by Muhammad Saleh Salga, Hapipah Mohd Ali, Mahmood Ameen Abdulla and Siddig Ibrahim Abdelwahab
Int. J. Mol. Sci. 2012, 13(2), 1393-1404; https://doi.org/10.3390/ijms13021393 - 27 Jan 2012
Cited by 26 | Viewed by 6493
Abstract
The current study described the synthesis and the in vivo acute oral toxicity evaluations in Sprague Dawley rats. The compounds were characterized by elemental analyses, LC-MS, FTIR, 1H NMR, 13C NMR and UV-visible spectroscopy. In the acute toxicity study, a single [...] Read more.
The current study described the synthesis and the in vivo acute oral toxicity evaluations in Sprague Dawley rats. The compounds were characterized by elemental analyses, LC-MS, FTIR, 1H NMR, 13C NMR and UV-visible spectroscopy. In the acute toxicity study, a single administration of the compounds was performed orally to the rats at the single doses of 2000 mg/kg and they were then monitored for possible side effects, mortality or behavioral changes up to 14 days. The serum level of aspartate (AST), alanine aminotransferases (ALT), alkaline phosphate (ALP), triglyceride, high density lipoprotein (HDL), immunoglobulins (GAM) and the C-reactive proteins did not significantly change. The hematological indices white blood cells (WBC), haematocrit (HCT), red blood cells (RBC), mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC), and mean corpuscular hemoglobin (MCH) were within the normal range. The renal function indices examined were also within the reference range. Generally, the compounds exhibited low toxic effects as required for further in vivo therapeutic studies. Full article
(This article belongs to the Section Green Chemistry)
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1195 KiB  
Article
Phylogeographical Analysis on Squalidus argentatus Recapitulates Historical Landscapes and Drainage Evolution on the Island of Taiwan and Mainland China
by Jin-Quan Yang, Wen-Qiao Tang, Te-Yu Liao, Yang Sun, Zhuo-Cheng Zhou, Chiao-Chuan Han, Dong Liu and Hung-Du Lin
Int. J. Mol. Sci. 2012, 13(2), 1405-1425; https://doi.org/10.3390/ijms13021405 - 30 Jan 2012
Cited by 37 | Viewed by 7967
Abstract
Phylogeographical analyses on Squalidus argentatus samples from thirteen localities within mainland China and Taiwan were conducted for biogeographic studies, as their dispersal strictly depends on geological evolution of the landmasses. A total of 95 haplotypes were genotyped for mtDNA cyt b gene in [...] Read more.
Phylogeographical analyses on Squalidus argentatus samples from thirteen localities within mainland China and Taiwan were conducted for biogeographic studies, as their dispersal strictly depends on geological evolution of the landmasses. A total of 95 haplotypes were genotyped for mtDNA cyt b gene in 160 specimens from nine river systems. Relatively high levels of haplotype diversity (h = 0.984) and low levels of nucleotide diversity (π = 0.020) were detected in S. argentatus. Two major phylogenetic haplotype groups, A and B, were revealed via phylogenetic analysis. The degree of intergroup divergence (3.96%) indicates that these groups diverged about 4.55 myr (million years) ago. Haplotype network and population analyses indicated significant genetic structure (FST = 0.775), largely concordant with the geographical location of the populations. According to SAMOVA analysis, we divided these populations into four units: Yangtze-Pearl, Qiantang-Minjiang, Jiulong-Beijiang and Taiwan groups. Mismatch distribution analysis, neutrality tests and Bayesian skyline plots indicated a significant population expansion for lineage A and B, approximately dated 0.35 and 0.04 myr ago, respectively. We found strong geographical organization of the haplotype clades across different geographic scales that can be explained by episodes of dispersal and population expansion followed by population fragmentation and restricted gene flow. Full article
(This article belongs to the Section Biochemistry)
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191 KiB  
Article
Chemical Composition and in Vitro Antifungal Activity Screening of the Allium ursinum L. (Liliaceae)
by Radu Vasile Bagiu, Brigitha Vlaicu and Monica Butnariu
Int. J. Mol. Sci. 2012, 13(2), 1426-1436; https://doi.org/10.3390/ijms13021426 - 30 Jan 2012
Cited by 84 | Viewed by 9527
Abstract
The objective of the study was to summarize the methods for isolating and identifying natural sulfur compounds from Allium ursinum (ramson) and to discuss the active constituents with regard to antifungal action. Using chromatographic techniques, the active constituents were isolated and subsequently identified. [...] Read more.
The objective of the study was to summarize the methods for isolating and identifying natural sulfur compounds from Allium ursinum (ramson) and to discuss the active constituents with regard to antifungal action. Using chromatographic techniques, the active constituents were isolated and subsequently identified. Analyses by high-performance liquid chromatography (HPLC) suggested that these compounds were sulfur constituents, with a characteristic absorbance at 250 nm. Gas chromatography-mass spectrometry (GC-MS) analyses allowed the chemical structures of the isolated constituents to be postulated. We adopted the same methods to identify the health-giving profiling of ramsons and the effects are thought to be primarily derived from the presence and breakdown of the alk(en)ylcysteine sulphoxide, alliin and its subsequent breakdown to allicin (sulfur-compounds of ramson) in connection with antifungal action. The aim of the study was the characterization of the chemical composition of ramsons and the testing of the action of the in vitro extracts, on different strains of Candida albicans. The main goal was to highlight the most efficient extracts of Allium ursinum that can provide long-term antifungal activity without remissions. The extracts from Allium ursinum plants, inhibited growth of Candida spp. cells at concentrations ranging from 0.5 to 4.0 mg/mL, while that of adherent cells at concentrations ranging from 1.0 to > 4.0 mg/mL, depending on the yeast and plant species. Full article
(This article belongs to the Special Issue Biocides)
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126 KiB  
Article
Isolation and Characterization of 21 Microsatellite Loci in Cardiocrinum giganteum var. yunnanense (Liliaceae), an Important Economic Plant in China
by Rong Li, Jie Yang, Junbo Yang and Zhiling Dao
Int. J. Mol. Sci. 2012, 13(2), 1437-1443; https://doi.org/10.3390/ijms13021437 - 31 Jan 2012
Cited by 7 | Viewed by 6048
Abstract
Twenty-one microsatellite markers from the genome of Cardiocrinum giganteum var. yunnanense, an important economic plant in China, were developed with a fast isolation protocol by amplified fragment length polymorphism of sequences containing repeats (FIASCO). Polymorphism within each locus was assessed in 24 [...] Read more.
Twenty-one microsatellite markers from the genome of Cardiocrinum giganteum var. yunnanense, an important economic plant in China, were developed with a fast isolation protocol by amplified fragment length polymorphism of sequences containing repeats (FIASCO). Polymorphism within each locus was assessed in 24 wild individuals from Gaoligong Mountains in western Yunnan Province, China. The number of alleles per locus ranged from 2 to 4 with a mean of 2.9. The expected and observed levels of heterozygosity ranged from 0.042 to 0.726 and from 0.000 to 1.000, with averages of 0.44 and 0.31, respectively. These polymorphic microsatellite markers should prove useful in population genetics studies and assessments of genetic variation to develop conservation and management strategies for this species. Full article
(This article belongs to the Section Biochemistry)
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729 KiB  
Article
Elevated Peripheral Blood Plasma Concentrations of Tie-2 and Angiopoietin 2 in Patients with Neuroendocrine Tumors
by Gabriela Melen-Mucha, Agata Niedziela, Slawomir Mucha, Ewelina Motylewska, Hanna Lawnicka, Jan Komorowski and Henryk Stepien
Int. J. Mol. Sci. 2012, 13(2), 1444-1460; https://doi.org/10.3390/ijms13021444 - 31 Jan 2012
Cited by 17 | Viewed by 5450
Abstract
Background: Gastro-entero-pancreatic/neuroendocrine (NET) tumors are highly vascularized neoplasms. However, our knowledge concerning circulating levels of the angiogenic factors in NET patients still remains insufficient. Methods: The aim of this study was to measure plasma concentrations of VEGF, angiopoietin 1 (Ang-1), angiopoietin 2 (Ang-2), [...] Read more.
Background: Gastro-entero-pancreatic/neuroendocrine (NET) tumors are highly vascularized neoplasms. However, our knowledge concerning circulating levels of the angiogenic factors in NET patients still remains insufficient. Methods: The aim of this study was to measure plasma concentrations of VEGF, angiopoietin 1 (Ang-1), angiopoietin 2 (Ang-2), soluble Tie-2, endostatin, osteopontin (OPN) and chromogranin A (CgA) in 36 NET patients and 16 controls. Results: Only the plasma concentrations of Tie-2 and CgA were higher in NET patients as compared to controls. These levels were within the reference range in controls; however one control demonstrated slightly elevated Tie-2 and 4 elevated CgA. Similarly, in the subgroup of patients with carcinoid syndrome, only Tie-2 and CgA concentrations were higher than those in patients with non-functioning NETs. In turn, in the subgroup of metastatic patients, only Ang-2 levels were higher than in those with localized disease. A positive correlation was found between Ang-2 and Tie-2 levels in metastatic patients and between Ang-1 and Tie-2 in localized NETs. Conclusions: The plasma concentration of Tie-2 is proposed as an additional marker for NET patients and seems to be similarly effective as the currently used CgA level. Moreover, higher plasma levels of Ang-2 together with the positive correlation between Ang-2 and Tie-2 levels in metastatic subjects, implies that cases with a Tie-2 level above the upper limits, together with higher level of Ang-2 seem to be highly predictive of metastases. Full article
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
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528 KiB  
Article
Nanoscopic and Photonic Ultrastructural Characterization of Two Distinct Insulin Amyloid States
by Katarzyna Maria Psonka-Antonczyk, Julien Duboisset, Bjørn Torger Stokke, Tamotsu Zako, Takahiro Kobayashi, Mizuo Maeda, Sofie Nyström, Jeff Mason, Per Hammarström, K. Peter R. Nilsson and Mikael Lindgren
Int. J. Mol. Sci. 2012, 13(2), 1461-1480; https://doi.org/10.3390/ijms13021461 - 01 Feb 2012
Cited by 9 | Viewed by 7866
Abstract
Two different conformational isoforms or amyloid strains of insulin with different cytotoxic capacity have been described previously. Herein these filamentous and fibrillar amyloid states of insulin were investigated using biophysical and spectroscopic techniques in combination with luminescent conjugated oligothiophenes (LCO). This new class [...] Read more.
Two different conformational isoforms or amyloid strains of insulin with different cytotoxic capacity have been described previously. Herein these filamentous and fibrillar amyloid states of insulin were investigated using biophysical and spectroscopic techniques in combination with luminescent conjugated oligothiophenes (LCO). This new class of fluorescent probes has a well defined molecular structure with a distinct number of thiophene units that can adopt different dihedral angles depending on its binding site to an amyloid structure. Based on data from surface charge, hydrophobicity, fluorescence spectroscopy and imaging, along with atomic force microscopy (AFM), we deduce the ultrastructure and fluorescent properties of LCO stained insulin fibrils and filaments. Combined total internal reflection fluorescence microscopy (TIRFM) and AFM revealed rigid linear fibrous assemblies of fibrils whereas filaments showed a short curvilinear morphology which assemble into cloudy deposits. All studied LCOs bound to the filaments afforded more blue-shifted excitation and emission spectra in contrast to those corresponding to the fibril indicating a different LCO binding site, which was also supported by less efficient hydrophobic probe binding. Taken together, the multi-tool approach used here indicates the power of ultrastructure identification applying AFM together with LCO fluorescence interrogation, including TIRFM, to resolve structural differences between amyloid states. Full article
(This article belongs to the Special Issue Protein Aggregation)
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394 KiB  
Article
Pharmacological Mechanisms Underlying Gastroprotective Activities of the Fractions Obtained from Polygonum minus in Sprague Dawley Rats
by Suhailah Wasman Qader, Mahmood Ameen Abdulla, Lee Suan Chua, Hasnah Mohd Sirat and Salehhuddin Hamdan
Int. J. Mol. Sci. 2012, 13(2), 1481-1496; https://doi.org/10.3390/ijms13021481 - 01 Feb 2012
Cited by 31 | Viewed by 9205
Abstract
The leaves of Polygonum minus were fractionated using an eluting solvent to evaluate the pharmacological mechanisms underlying the anti-ulcerogenic activity of P. minus. Different P. minus fractions were obtained and evaluated for their ulcer preventing capabilities using the ethanol induction method. In [...] Read more.
The leaves of Polygonum minus were fractionated using an eluting solvent to evaluate the pharmacological mechanisms underlying the anti-ulcerogenic activity of P. minus. Different P. minus fractions were obtained and evaluated for their ulcer preventing capabilities using the ethanol induction method. In this study, Sprague Dawley rats weighing 150–200 g were used. Different parameters were estimated to identify the active fraction underlying the mechanism of the gastroprotective action of P. minus: the gastric mucus barrier, as well as superoxide dismutase, total hexosamine, and prostaglandin synthesis. Amongst the five fractions from the ethanolic extract of P. minus, the ethyl acetate:methanol 1:1 v/v fraction (F2) significantly (p < 0.005) exhibited better inhibition of ulcer lesions in a dose-dependent manner. In addition, rats pre-treated with F2 showed a significant elevation in superoxide dismutase (SOD), hexosamine and PGE2 levels in the stomach wall mucosa in a dose-dependent matter. Based on these results, the ethyl acetate:methanol 1:1 v/v fraction was considered to be the best fraction for mucous protection in the ethanol induction model. The mechanisms underlying this protection were attributed to the synthesis of antioxidants and PGE2. Full article
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411 KiB  
Article
Olmesartan Attenuates the Impairment of Endothelial Cells Induced by Oxidized Low Density Lipoprotein through Downregulating Expression of LOX-1
by Hua Zhang, Genshan Ma, Yuyu Yao, Huidong Qian, Weizhang Li, Xinjun Chen, Wenlong Jiang and Ruolong Zheng
Int. J. Mol. Sci. 2012, 13(2), 1512-1523; https://doi.org/10.3390/ijms13021512 - 01 Feb 2012
Cited by 13 | Viewed by 6506
Abstract
Oxidized low density lipoprotein (ox-LDL) and its receptor, lectin-Like ox-LDL receptor-1 (LOX-1), play important roles in the development of endothelial injuries. Olmesartan can protect endothelial cells from the impairment caused by various pathological stimulations. In the present study we investigated whether olmesartan decreased [...] Read more.
Oxidized low density lipoprotein (ox-LDL) and its receptor, lectin-Like ox-LDL receptor-1 (LOX-1), play important roles in the development of endothelial injuries. Olmesartan can protect endothelial cells from the impairment caused by various pathological stimulations. In the present study we investigated whether olmesartan decreased the impairment of endothelial cells induced by ox-LDL by exerting its effects on LOX-1 both in vitro and in vivo. Incubation of cultured endothelial cells of neonatal rats with ox-LDL for 24 h or infusion of ox-LDL in mice for 3 weeks led to the remarkable impairment of endothelial cells, including increased lactate dehydrogenase synthesis, phosphorylation of p38 mitogen-activated protein kinases (p38 MAPK) and expression of apoptotic genes such as B-cell leukemia/lymphoma 2 (Bcl-2)-associated X protein (Bax) and caspase-3. Simultaneously, the cell vitality and expression of Bcl-2 gene were greatly reduced. All these effects, however, were significantly suppressed by the treatment with olmesartan. Furthermore, ox-LDL promoted up-regulation of LOX-1 expression either in cultured endothelial cells or in the aortas of mice, which was reversed with the administration of olmesartan. Our data indicated that olmesartan may attenuate the impairment of endothelial cell via down-regulation of the increased LOX-1 expression induced by ox-LDL. Full article
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724 KiB  
Article
Composition, Structure and Functional Properties of Protein Concentrates and Isolates Produced from Walnut (Juglans regia L.)
by Xiaoying Mao and Yufei Hua
Int. J. Mol. Sci. 2012, 13(2), 1561-1581; https://doi.org/10.3390/ijms13021561 - 02 Feb 2012
Cited by 192 | Viewed by 11243
Abstract
In this study, composition, structure and the functional properties of protein concentrate (WPC) and protein isolate (WPI) produced from defatted walnut flour (DFWF) were investigated. The results showed that the composition and structure of walnut protein concentrate (WPC) and walnut protein isolate (WPI) [...] Read more.
In this study, composition, structure and the functional properties of protein concentrate (WPC) and protein isolate (WPI) produced from defatted walnut flour (DFWF) were investigated. The results showed that the composition and structure of walnut protein concentrate (WPC) and walnut protein isolate (WPI) were significantly different. The molecular weight distribution of WPI was uniform and the protein composition of DFWF and WPC was complex with the protein aggregation. H0 of WPC was significantly higher ( p < 0.05) than those of DFWF and WPI, whilst WPI had a higher H0 compared to DFWF. The secondary structure of WPI was similar to WPC. WPI showed big flaky plate like structures; whereas WPC appeared as a small flaky and more compact structure. The most functional properties of WPI were better than WPC. In comparing most functional properties of WPI and WPC with soybean protein concentrate and isolate, WPI and WPC showed higher fat absorption capacity (FAC). Emulsifying properties and foam properties of WPC and WPI in alkaline pH were comparable with that of soybean protein concentrate and isolate. Walnut protein concentrates and isolates can be considered as potential functional food ingredients. Full article
(This article belongs to the Section Biochemistry)
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578 KiB  
Article
Functional Expression of an Orchid Fragrance Gene in Lactococcus lactis
by Adelene Ai Lian Song, Janna O. Abdullah, Mohd Puad Abdullah, Norazizah Shafee and Raha A. Rahim
Int. J. Mol. Sci. 2012, 13(2), 1582-1597; https://doi.org/10.3390/ijms13021582 - 02 Feb 2012
Cited by 23 | Viewed by 8283
Abstract
Vanda Mimi Palmer (VMP), an orchid hybrid of Vanda tesselata and Vanda Tan Chay Yan is a highly scented tropical orchid which blooms all year round. Previous studies revealed that VMP produces a variety of isoprenoid volatiles during daylight. Isoprenoids are well known [...] Read more.
Vanda Mimi Palmer (VMP), an orchid hybrid of Vanda tesselata and Vanda Tan Chay Yan is a highly scented tropical orchid which blooms all year round. Previous studies revealed that VMP produces a variety of isoprenoid volatiles during daylight. Isoprenoids are well known to contribute significantly to the scent of most fragrant plants. They are a large group of secondary metabolites which may possess valuable characteristics such as flavor, fragrance and toxicity and are produced via two pathways, the mevalonate (MVA) pathway or/and the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway. In this study, a sesquiterpene synthase gene denoted VMPSTS, previously isolated from a floral cDNA library of VMP was cloned and expressed in Lactococcus lactis to characterize the functionality of the protein. L. lactis, a food grade bacterium which utilizes the mevalonate pathway for isoprenoid production was found to be a suitable host for the characterization of plant terpene synthases. Through recombinant expression of VMPSTS, it was revealed that VMPSTS produced multiple sesquiterpenes and germacrene D dominates its profile. Full article
(This article belongs to the Section Biochemistry)
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Article
Antinociceptive and Anti-Inflammatory Effects of Octacosanol from the Leaves of Sabicea grisea var. grisea in Mice
by Anderson Marques de Oliveira, Lucia M. Conserva, Jamylle N. De Souza Ferro, Fabíola de Almeida Brito, Rosângela P. Lyra Lemos and Emiliano Barreto
Int. J. Mol. Sci. 2012, 13(2), 1598-1611; https://doi.org/10.3390/ijms13021598 - 02 Feb 2012
Cited by 80 | Viewed by 8224
Abstract
Sabicea species are used in the Amazon for treatment of fever and malaria, which suggests that its chemical constituents may have some effect on pain and inflammation. Phytochemical analysis of the hexane fraction obtained from the crude ethanol extract from Sabicea grisea var. [...] Read more.
Sabicea species are used in the Amazon for treatment of fever and malaria, which suggests that its chemical constituents may have some effect on pain and inflammation. Phytochemical analysis of the hexane fraction obtained from the crude ethanol extract from Sabicea grisea var. grisea Cham. & Schltdl (Rubiaceae), an endemic plant in Brazil, resulted in the isolation of octacosanol. This study investigated the antinociceptive and anti-inflammatory effects of the octacosanol in different experimental models. The crude ethanolic extract and hexane fraction obtained from the leaves of S. grisea produced an inhibition of acetic acid-induced pain. Moreover, octacosanol isolated from the hexane fraction produced a significant inhibition of pain response elicited by acetic acid. Pre-treatment with yohimbine, an alpha 2-adrenergic receptor antagonist, notably reversed the antinociceptive activity induced by octacosanol in the abdominal constriction test. Furthermore, mice treated with octacosanol did not exhibit any behavioral alteration during the hot plate and rota-rod tests, indicating non-participation of the supraspinal components in the modulation of pain by octacosanol with no motor abnormality. In the formalin test, octacosanol did not inhibit the licking time in first phase (neurogenic pain), but significantly inhibited the licking time in second phase (inflammatory pain) of mice. The anti-inflammatory effect of octacosanol was evaluated using carrageenan-induced pleurisy. The octacosanol significantly reduced the total leukocyte count and neutrophils influx, as well as TNF-α levels in the carrageenan-induced pleurisy. This study revealed that the mechanism responsible for the antinociceptive and anti-inflammatory effects of the octacosanol appears to be partly associated with an inhibition of alpha 2-adrenergic transmission and an inhibition of pathways dependent on pro-inflammatory cytokines. Finally, these results demonstrated that the octacosanol from the leaves of S. grisea possesses antinociceptive and anti-inflammatory activities, which could be of relevance for the pharmacological control of pain and inflammatory processes. Full article
(This article belongs to the Section Biochemistry)
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Article
Tetrachloridocuprates(II)—Synthesis and Electron Paramagnetic Resonance (EPR) Spectroscopy
by Alette Winter, André Zabel and Peter Strauch
Int. J. Mol. Sci. 2012, 13(2), 1612-1619; https://doi.org/10.3390/ijms13021612 - 02 Feb 2012
Cited by 18 | Viewed by 7634
Abstract
Ionic liquids (ILs) on the basis of metal containing anions and/or cations are of interest for a variety of technical applications e.g., synthesis of particles, magnetic or thermochromic materials. We present the synthesis and the results of electron paramagnetic resonance (EPR) spectroscopic analyses [...] Read more.
Ionic liquids (ILs) on the basis of metal containing anions and/or cations are of interest for a variety of technical applications e.g., synthesis of particles, magnetic or thermochromic materials. We present the synthesis and the results of electron paramagnetic resonance (EPR) spectroscopic analyses of a series of some new potential ionic liquids based on tetrachloridocuprates(II), [CuCl4]2−, with different sterically demanding cations: hexadecyltrimethylammonium 1, tetradecyltrimethylammonium 2, tetrabutylammonium 3 and benzyltriethylammonium 4. The cations in the new compounds were used to achieve a reasonable separation of the paramagnetic Cu(II) ions for EPR spectroscopy. The EPR hyperfine structure was not resolved. This is due to the exchange broadening, resulting from still incomplete separation of the paramagnetic Cu(II) centers. Nevertheless, the principal values of the electron Zeemann tensor (g and g) of the complexes could be determined. Even though the solid substances show slightly different colors, the UV/Vis spectra are nearly identical, indicating structural changes of the tetrachloridocuprate moieties between solid state and solution. The complexes have a promising potential e.g., as high temperature ionic liquids, as precursors for the formation of copper chloride particles or as catalytic paramagnetic ionic liquids. Full article
(This article belongs to the Special Issue Metal Containing Ionic Liquids)
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Article
Acidic Polysaccharide Extracts from Gastrodia Rhizomes Suppress the Atherosclerosis Risk Index through Inhibition of the Serum Cholesterol Composition in Sprague Dawley Rats Fed a High-Fat Diet
by Kui-Jin Kim, Ok-Hwan Lee, Chan-Kyu Han, Young-Chan Kim and Hee-Do Hong
Int. J. Mol. Sci. 2012, 13(2), 1620-1631; https://doi.org/10.3390/ijms13021620 - 02 Feb 2012
Cited by 19 | Viewed by 6700
Abstract
Obesity is associated with a broad spectrum of cardio-metabolic disturbances, including atherosclerosis and cardiovascular disease (CDV). A high-fat diet has been shown to cause an elevation of the plasma cholesterol levels in humans, and the control of serum cholesterol has been demonstrated to [...] Read more.
Obesity is associated with a broad spectrum of cardio-metabolic disturbances, including atherosclerosis and cardiovascular disease (CDV). A high-fat diet has been shown to cause an elevation of the plasma cholesterol levels in humans, and the control of serum cholesterol has been demonstrated to be important in the prevention of CVD and atherosclerosis. The aims of this study were to demonstrate that crude and acidic polysaccharide extracts from Gastrodia rhizomes suppress atherosclerosis through the regulation of serum lipids in Sprague Dawley (SD) rats fed a high-fat diet. We examined the concentrations of serum lipids, including total cholesterol, triglycerides, high-density lipoproteins (HDL) cholesterol, and low-density lipoproteins (LDL) cholesterol, in SD rats fed a high-fat diet and evaluated the atherogenic index. Here, we show that both crude and acidic polysaccharide extracts from Gastrodia rhizomes inhibited the total cholesterol and LDL levels. Moreover, there was a significantly suppressed atherosclerosis risk due to the acidic polysaccharide extract from Gastrodia rhizome. Taken together, our results suggested that acidic polysaccharide extracts from Gastrodia rhizomes might be beneficial for lowering the incidence of CVD and atherosclerosis by reducing the de novo synthesis of total cholesterol and the LDL levels. Full article
(This article belongs to the Section Biochemistry)
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Article
Analysis of Snail-1, E-Cadherin and Claudin-1 Expression in Colorectal Adenomas and Carcinomas
by Michala Bezdekova, Svetlana Brychtova, Eva Sedlakova, Katerina Langova, Tomas Brychta and Kamil Belej
Int. J. Mol. Sci. 2012, 13(2), 1632-1643; https://doi.org/10.3390/ijms13021632 - 02 Feb 2012
Cited by 43 | Viewed by 7319
Abstract
We report the expression of Snail-1, E-cadherin and claudin-1 by indirect immunohistochemistry in colonic neoplasia. Snail-1 is a zinc finger transcription factor expressed in cells that already have undergone almost complete epithelial-mesenchymal transition (EMT) and have already evaded from the tumor. The main [...] Read more.
We report the expression of Snail-1, E-cadherin and claudin-1 by indirect immunohistochemistry in colonic neoplasia. Snail-1 is a zinc finger transcription factor expressed in cells that already have undergone almost complete epithelial-mesenchymal transition (EMT) and have already evaded from the tumor. The main mechanism by which Snail induces EMT is downregulation of E-cadherin, of which expression was shown to be frequently downregulated in many different types of tumors, where it accompanies the invasiveness and metastatic behavior of malignant cells. Moreover, Snail-1 may downregulate the expression of claudin-1, a cell-cell adhesion protein which plays a likely role in progression and dissemination during tumorigenesis. Snail-1 was expressed in both carcinoma and adenoma cells with histologically normal epithelium in the mucosa, adjacent to the tumors, without significant differences, and predominant strong intensity of staining. Statistically significant differences were revealed between normal and tumorous epithelium (p = 0.003) at the subcellular level, where the shift of the protein to the cytoplasm with combined cytoplasmic/nuclear or pure cytoplasmic expression was observed. E-cadherin expression was present in 100% of cases of both adenocarcinomas and adenomas, with prevailing strong membranous immunoreactivity and no differences between protein expression in tumors and normal mucosa. Predominating strong positivity of claudin-1 was detected in tumor cells of adenocarcinomas and adenomas. Marked differences were seen in protein localization, where membranous staining, typical for nontumorous epithelium, changed to combined membranous/cytoplasmic expression in adenocarcinomas (p = 0.0001) and adenomas (0.0002), in which cytoplasmic shift was associated with a higher degree of dysplasia. Furthermore, membranous/cytoplasmic localization was more frequent in the carcinoma group (87%) in comparison with adenomas (51%) (p = 0.0001). We conclude that dystopic subcellular localizations of Snail-1 and claudin-1 may participate in changes of cellular morphology and behavior which might be associated with altered effectory pathways of proteins and thus substantially contribute to the cancer development. Full article
(This article belongs to the Special Issue Advances in Molecular Pathology)
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Article
Coenzyme Q Metabolism Is Disturbed in High Fat Diet-Induced Non Alcoholic Fatty Liver Disease in Rats
by Elena Bravo, Simonetta Palleschi, Barbara Rossi, Mariarosaria Napolitano, Luca Tiano, Emanuela D’Amore and Kathleen M Botham
Int. J. Mol. Sci. 2012, 13(2), 1644-1657; https://doi.org/10.3390/ijms13021644 - 02 Feb 2012
Cited by 12 | Viewed by 7237
Abstract
Oxidative stress is believed to be a major contributory factor in the development of non alcoholic fatty liver disease (NAFLD), the most common liver disorder worldwide. In this study, the effects of high fat diet-induced NAFLD on Coenzyme Q (CoQ) metabolism and plasma [...] Read more.
Oxidative stress is believed to be a major contributory factor in the development of non alcoholic fatty liver disease (NAFLD), the most common liver disorder worldwide. In this study, the effects of high fat diet-induced NAFLD on Coenzyme Q (CoQ) metabolism and plasma oxidative stress markers in rats were investigated. Rats were fed a standard low fat diet (control) or a high fat diet (57% metabolizable energy as fat) for 18 weeks. The concentrations of total (reduced + oxidized) CoQ9 were increased by > 2 fold in the plasma of animals fed the high fat diet, while those of total CoQ10 were unchanged. Reduced CoQ levels were raised, but oxidized CoQ levels were not, thus the proportion in the reduced form was increased by about 75%. A higher percentage of plasma CoQ9 as compared to CoQ10 was in the reduced form in both control and high fat fed rats. Plasma protein thiol (SH) levels were decreased in the high fat-fed rats as compared to the control group, but concentrations of lipid hydroperoxides and low density lipoprotein (LDL) conjugated dienes were unchanged. These results indicate that high fat diet-induced NAFLD in rats is associated with altered CoQ metabolism and increased protein, but not lipid, oxidative stress. Full article
(This article belongs to the Special Issue Antioxidants)
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Article
Preparation of TiO2 Nanocrystallite Powders Coated with 9 mol% ZnO for Cosmetic Applications in Sunscreens
by Horng-Huey Ko, Hui-Ting Chen, Feng-Ling Yen, Wan-Chen Lu, Chih-Wei Kuo and Moo-Chin Wang
Int. J. Mol. Sci. 2012, 13(2), 1658-1669; https://doi.org/10.3390/ijms13021658 - 03 Feb 2012
Cited by 35 | Viewed by 8684
Abstract
The preparation of TiO2 nanocrystallite powders coated with and without 9 mol% ZnO has been studied for cosmetic applications in sunscreens by a co-precipitation process using TiCl4 and Zn(NO3)2·6H2O as starting materials. XRD results show [...] Read more.
The preparation of TiO2 nanocrystallite powders coated with and without 9 mol% ZnO has been studied for cosmetic applications in sunscreens by a co-precipitation process using TiCl4 and Zn(NO3)2·6H2O as starting materials. XRD results show that the phases of anatase TiO2 and rutile TiO2 coexist for precursor powders without added ZnO (T-0Z) and calcined at 523 to 973 K for 2 h. When the T-0Z precursor powders are calcined at 1273 K for 2 h, only the rutile TiO2 appears. In addition, when the TiO2 precursor powders contain 9 mol% ZnO (T-9Z) are calcined at 873 to 973 K for 2 h, the crystallized samples are composed of the major phase of rutile TiO2 and the minor phases of anatase TiO2 and Zn2Ti3O8. The analyses of UV/VIS/NIR spectra reveal that the absorption of the T-9Z precursor powders after being calcined has a red-shift effect in the UV range with increasing calcination temperature. Therefore, the TiO2 nanocrystallite powders coated with 9 mol% ZnO can be used as the attenuate agent in the UV-A region for cosmetic applications in sunscreens. Full article
(This article belongs to the Section Materials Science)
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Article
Early Exercise Affects Mitochondrial Transcription Factors Expression after Cerebral Ischemia in Rats
by Qi Zhang, Yi Wu, Hongying Sha, Pengyue Zhang, Jie Jia, Yongshan Hu and Jianhong Zhu
Int. J. Mol. Sci. 2012, 13(2), 1670-1679; https://doi.org/10.3390/ijms13021670 - 06 Feb 2012
Cited by 43 | Viewed by 6679
Abstract
Increasing evidence shows that exercise training is neuroprotective after stroke, but the underlying mechanisms are unknown. To clarify this critical issue, the current study investigated the effects of early treadmill exercise on the expression of mitochondrial biogenesis factors. Adult rats were subjected to [...] Read more.
Increasing evidence shows that exercise training is neuroprotective after stroke, but the underlying mechanisms are unknown. To clarify this critical issue, the current study investigated the effects of early treadmill exercise on the expression of mitochondrial biogenesis factors. Adult rats were subjected to ischemia induced by middle cerebral artery occlusion followed by reperfusion. Expression of two genes critical for transcriptional regulation of mitochondrial biogenesis, peroxisome proliferator-activated receptor coactivator-1 (PGC-1) and nuclear respiratory factor-1 (NRF-1), were examined by RT-PCR after five days of exercise starting at 24 h after ischemia. Mitochondrial protein cytochrome C oxidase subunit IV (COX IV) was detected by Western blot. Neurological status and cerebral infarct volume were evaluated as indices of brain damage. Treadmill training increased levels of PGC-1 and NRF-1 mRNA, indicating that exercise promotes rehabilitation after ischemia via regulation of mitochondrial biogenesis. Full article
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Article
Voltage Gated Ion Channel Function: Gating, Conduction, and the Role of Water and Protons
by Alisher M. Kariev and Michael E. Green
Int. J. Mol. Sci. 2012, 13(2), 1680-1709; https://doi.org/10.3390/ijms13021680 - 06 Feb 2012
Cited by 18 | Viewed by 6612
Abstract
Ion channels, which are found in every biological cell, regulate the concentration of electrolytes, and are responsible for multiple biological functions, including in particular the propagation of nerve impulses. The channels with the latter function are gated (opened) by a voltage signal, which [...] Read more.
Ion channels, which are found in every biological cell, regulate the concentration of electrolytes, and are responsible for multiple biological functions, including in particular the propagation of nerve impulses. The channels with the latter function are gated (opened) by a voltage signal, which allows Na+ into the cell and K+ out. These channels have several positively charged amino acids on a transmembrane domain of their voltage sensor, and it is generally considered, based primarily on two lines of experimental evidence, that these charges move with respect to the membrane to open the channel. At least three forms of motion, with greatly differing extents and mechanisms of motion, have been proposed. There is a “gating current”, a capacitative current preceding the channel opening, that corresponds to several charges (for one class of channel typically 12–13) crossing the membrane field, which may not require protein physically crossing a large fraction of the membrane. The coupling to the opening of the channel would in these models depend on the motion. The conduction itself is usually assumed to require the “gate” of the channel to be pulled apart to allow ions to enter as a section of the protein partially crosses the membrane, and a selectivity filter at the opposite end of the channel determines the ion which is allowed to pass through. We will here primarily consider K+ channels, although Na+ channels are similar. We propose that the mechanism of gating differs from that which is generally accepted, in that the positively charged residues need not move (there may be some motion, but not as gating current). Instead, protons may constitute the gating current, causing the gate to open; opening consists of only increasing the diameter at the gate from approximately 6 Å to approximately 12 Å. We propose in addition that the gate oscillates rather than simply opens, and the ion experiences a barrier to its motion across the channel that is tuned by the water present within the channel. Our own quantum calculations as well as numerous experiments of others are interpreted in terms of this hypothesis. It is also shown that the evidence that supports the motion of the sensor as the gating current can also be consistent with the hypothesis we present. Full article
(This article belongs to the Special Issue From Molecules to Nanomaterials)
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Article
Screening of Crude Plant Extracts with Anti-Obesity Activity
by Changhyun Roh and Uhee Jung
Int. J. Mol. Sci. 2012, 13(2), 1710-1719; https://doi.org/10.3390/ijms13021710 - 06 Feb 2012
Cited by 114 | Viewed by 13510
Abstract
Obesity is a global health problem. It is also known to be a risk factor for the development of metabolic disorders, type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis. In this study, we screened crude extracts from 400 plants to test [...] Read more.
Obesity is a global health problem. It is also known to be a risk factor for the development of metabolic disorders, type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis. In this study, we screened crude extracts from 400 plants to test their anti-obesity activity using porcine pancreatic lipase assay (PPL; triacylglycerol lipase, EC 3.1.1.3) in vitro activity. Among the 400 plants species examined, 44 extracts from plants, showed high anti-lipase activity using 2,4-dinitrophenylbutyrate as a substrate in porcine pancreatic lipase assay. Furthermore, 44 plant extracts were investigated for their inhibition of lipid accumulation in 3T3-L1 cells. Among these 44 extracts examined, crude extracts from 4 natural plant species were active. Salicis Radicis Cortex had the highest fat inhibitory activity, whereas Rubi Fructus, Corni Fructus, and Geranium nepalense exhibited fat inhibitory capacity higher than 30% at 100 μg/mL in 3T3-L1 adipocytes, suggesting anti-obesity activity. These results suggest that four potent plant extracts might be of therapeutic interest with respect to the treatment of obesity. Full article
(This article belongs to the Section Biochemistry)
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745 KiB  
Article
The Effect of C-Terminal Helix on the Stability of FF Domain Studied by Molecular Dynamics Simulation
by Liling Zhao, Zanxia Cao and Jihua Wang
Int. J. Mol. Sci. 2012, 13(2), 1720-1732; https://doi.org/10.3390/ijms13021720 - 07 Feb 2012
Cited by 1 | Viewed by 6010
Abstract
To investigate the effect of C-terminal helix on the stability of the FF domain, we studied the native domain FF3-71 from human HYPA/FBP11 and the truncated version FF3-60 with C-terminal helix being deleted by molecular dynamics simulations with GROMACS package and [...] Read more.
To investigate the effect of C-terminal helix on the stability of the FF domain, we studied the native domain FF3-71 from human HYPA/FBP11 and the truncated version FF3-60 with C-terminal helix being deleted by molecular dynamics simulations with GROMACS package and GROMOS 43A1 force field. The results indicated that the structures of truncated version FF3-60 were evident different from those of native partner FF3-71. Compared with FF3-71, the FF3-60 lost some native contacts and exhibited some similar structural characters to those of intermediate state. The C-terminal helix played a major role in stabilizing the FF3-71 domain. To a certain degree, the FF domain had a tendency to form an intermediate state without the C-terminal helix. In our knowledge, this was the first study to examine the role of C-terminal helix of FF domain in detail by molecular dynamics simulations, which was useful to understand the three-state folding mechanism of the small FF domain. Full article
(This article belongs to the Special Issue Advances in Biomolecular Simulation)
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415 KiB  
Article
Characterization of Catalase from Psychrotolerant Psychrobacter piscatorii T-3 Exhibiting High Catalase Activity
by Hideyuki Kimoto, Kazuaki Yoshimune, Hidetoshi Matsuyma and Isao Yumoto
Int. J. Mol. Sci. 2012, 13(2), 1733-1746; https://doi.org/10.3390/ijms13021733 - 07 Feb 2012
Cited by 19 | Viewed by 6612
Abstract
A psychrotolerant bacterium, strain T-3 (identified as Psychrobacter piscatorii), that exhibited an extraordinarily high catalase activity was isolated from the drain pool of a plant that uses H2O2 as a bleaching agent. Its cell extract exhibited a catalase activity [...] Read more.
A psychrotolerant bacterium, strain T-3 (identified as Psychrobacter piscatorii), that exhibited an extraordinarily high catalase activity was isolated from the drain pool of a plant that uses H2O2 as a bleaching agent. Its cell extract exhibited a catalase activity (19,700 U·mg protein−1) that was higher than that of Micrococcus luteus used for industrial catalase production. Catalase was approximately 10% of the total proteins in the cell extract of the strain. The catalase (PktA) was purified homogeneously by only two purification steps, anion exchange and hydrophobic chromatographies. The purified catalase exhibited higher catalytic efficiency and higher sensitivity of activity at high temperatures than M. luteus catalase. The deduced amino acid sequence showed the highest homology with catalase of Psycrobacter cryohalolentis, a psychrotolelant bacterium obtained from Siberian permafrost. These findings suggest that the characteristics of the PktA molecule reflected the taxonomic relationship of the isolate as well as the environmental conditions (low temperatures and high concentrations of H2O2) under which the bacterium survives. Strain T-3 efficiently produces a catalase (PktA) at a higher rate than Exiguobacterium oxidotolerans, which produces a very strong activity of catalase (EktA) at a moderate rate, in order to adapt to high concentration of H2O2. Full article
(This article belongs to the Section Biochemistry)
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Article
Mitochondrial Protection and Anti-aging Activity of Astragalus Polysaccharides and Their Potential Mechanism
by Xing-Tai Li, Ya-Kui Zhang, Hai-Xue Kuang, Feng-Xin Jin, De-Wen Liu, Ming-Bo Gao, Ze Liu and Xiao-Juan Xin
Int. J. Mol. Sci. 2012, 13(2), 1747-1761; https://doi.org/10.3390/ijms13021747 - 07 Feb 2012
Cited by 106 | Viewed by 11461
Abstract
The current study was performed to investigate mitochondrial protection and anti-aging activity of Astragalus polysaccharides (APS) and the potential underlying mechanism. Lipid peroxidation of liver and brain mitochondria was induced by Fe2+–Vit C in vitro. Thiobarbituric acid (TBA) colorimetry was [...] Read more.
The current study was performed to investigate mitochondrial protection and anti-aging activity of Astragalus polysaccharides (APS) and the potential underlying mechanism. Lipid peroxidation of liver and brain mitochondria was induced by Fe2+–Vit C in vitro. Thiobarbituric acid (TBA) colorimetry was used to measure the content of thiobarbituric acid reactive substances (TBARS). Mouse liver mitochondrial permeability transition (PT) was induced by calcium overload in vitro and spectrophotometry was used to measure it. The scavenging activities of APS on superoxide anion (O2•-) and hydroxyl radical (•OH), which were produced by reduced nicotinamide adenine dinucleotide (NADH)—N-Methylphenazonium methyl sulfate (PMS) and hydrogen peroxide (H2O2)–Fe2+ system respectively, were measured by 4-nitrobluetetrazolium chloride (NBT) reduction and Fenton reaction colorimetry respectively. The Na2S2O3 titration method was used to measure the scavenging activities of APS on H2O2. APS could inhibit TBARS production, protect mitochondria from PT, and scavenge O2•-, •OH and H2O2 significantly in a concentration-dependent manner respectively. The back of the neck of mice was injected subcutaneously with D-galactose to induce aging at a dose of 100 mg/kg/d for seven weeks. Moreover, the activities of catalase (CAT), surperoxide dismutase (SOD) and glutathione peroxidase (GPx) and anti-hydroxyl radical which were assayed by using commercial monitoring kits were increased significantly in vivo by APS. According to this research, APS protects mitochondria by scavenging reactive oxygen species (ROS), inhibiting mitochondrial PT and increasing the activities of antioxidases. Therefore, APS has the effect of promoting health. Full article
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Article
10-Shogaol, an Antioxidant from Zingiber officinale for Skin Cell Proliferation and Migration Enhancer
by Chung-Yi Chen, Kuo-Chen Cheng, Andy Y Chang, Ying-Ting Lin, You-Cheng Hseu and Hui-Min Wang
Int. J. Mol. Sci. 2012, 13(2), 1762-1777; https://doi.org/10.3390/ijms13021762 - 08 Feb 2012
Cited by 49 | Viewed by 9263
Abstract
In this work, one of Zingiber officinale components, 10-shogaol, was tested with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating ability, and reducing power to show antioxidant activity. 10-Shogaol promoted human normal epidermal keratinocytes and dermal fibroblasts cell growths. 10-Shogaol enhanced growth factor production in [...] Read more.
In this work, one of Zingiber officinale components, 10-shogaol, was tested with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating ability, and reducing power to show antioxidant activity. 10-Shogaol promoted human normal epidermal keratinocytes and dermal fibroblasts cell growths. 10-Shogaol enhanced growth factor production in transforming growth factor-β (TGF-β), platelet derived growth factor-αβ (PDGF-αβ) and vascular endothelial growth factors (VEGF) of both cells. In the in vitro wound healing assay for 12 or 24 h, with 10-shogaol, the fibroblasts and keratinocytes migrated more rapidly than the vehicle control group. Thus, this study substantiates the target compound, 10-shogaol, as an antioxidant for human skin cell growth and a migration enhancer with potential to be a novel wound repair agent. Full article
(This article belongs to the Special Issue Antioxidants)
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Article
Cinnamic Acid and Its Derivatives Inhibit Fructose-Mediated Protein Glycation
by Sirichai Adisakwattana, Weerachat Sompong, Aramsri Meeprom, Sathaporn Ngamukote and Sirintorn Yibchok-anun
Int. J. Mol. Sci. 2012, 13(2), 1778-1789; https://doi.org/10.3390/ijms13021778 - 08 Feb 2012
Cited by 119 | Viewed by 8844
Abstract
Cinnamic acid and its derivatives have shown a variety of pharmacologic properties. However, little is known about the antiglycation properties of cinnamic acid and its derivatives. The present study sought to characterize the protein glycation inhibitory activity of cinnamic acid and its derivatives [...] Read more.
Cinnamic acid and its derivatives have shown a variety of pharmacologic properties. However, little is known about the antiglycation properties of cinnamic acid and its derivatives. The present study sought to characterize the protein glycation inhibitory activity of cinnamic acid and its derivatives in a bovine serum albumin (BSA)/fructose system. The results demonstrated that cinnamic acid and its derivatives significantly inhibited the formation of advanced glycation end products (AGEs) by approximately 11.96–63.36% at a concentration of 1 mM. The strongest inhibitory activity against the formation of AGEs was shown by cinnamic acid. Furthermore, cinnamic acid and its derivatives reduced the level of fructosamine, the formation of Nε-(carboxymethyl) lysine (CML), and the level of amyloid cross β-structure. Cinnamic acid and its derivatives also prevented oxidative protein damages, including effects on protein carbonyl formation and thiol oxidation of BSA. Our findings may lead to the possibility of using cinnamic acid and its derivatives for preventing AGE-mediated diabetic complications. Full article
(This article belongs to the Section Biochemistry)
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Article
Lipid Peroxidative Damage on Cisplatin Exposure and Alterations in Antioxidant Defense System in Rat Kidneys: A Possible Protective Effect of Selenium
by Branka I. Ognjanović, Nataša Z. Djordjević, Miloš M. Matić, Jasmina M. Obradović, Jelena M. Mladenović, Andraš Š. Štajn and Zorica S. Saičić
Int. J. Mol. Sci. 2012, 13(2), 1790-1803; https://doi.org/10.3390/ijms13021790 - 08 Feb 2012
Cited by 102 | Viewed by 8570
Abstract
Cisplatin (Cis-diamminedichloroplatinum II, CP) is an important chemotherapeutic agent, useful in the treatment of several cancers, but with several side effects such as nephrotoxicity. The present study investigated the possible protective effect of selenium (Se) against CP-induced oxidative stress in the [...] Read more.
Cisplatin (Cis-diamminedichloroplatinum II, CP) is an important chemotherapeutic agent, useful in the treatment of several cancers, but with several side effects such as nephrotoxicity. The present study investigated the possible protective effect of selenium (Se) against CP-induced oxidative stress in the rat kidneys. Male Wistar albino rats were injected with a single dose of cisplatin (7 mg CP/kg b.m., i.p.) and selenium (6 mg Se/kg b.m, as Na2SeO3, i.p.), alone or in combination. The obtained results showed that CP increased lipid peroxidation (LPO) and decreased reduced glutathione (GSH) concentrations, suggesting the CP-induced oxidative stress, while Se treatment reversed this change to control values. Acute intoxication of rats with CP was followed by statistically significant decreased activity of antioxidant defense enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and glutathione-S-transferase (GST). Treatment with Se reversed CP-induced alterations of antioxidant defense enzyme activities and significantly prevented the CP-induced kidney damage. Full article
(This article belongs to the Special Issue Antioxidants)
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Article
Isolation and Characterization of Activators of ERK/MAPK from Citrus Plants
by Yoshiko Furukawa, Satoshi Okuyama, Yoshiaki Amakura, Sono Watanabe, Takahiro Fukata, Mitsunari Nakajima, Morio Yoshimura and Takashi Yoshida
Int. J. Mol. Sci. 2012, 13(2), 1832-1845; https://doi.org/10.3390/ijms13021832 - 09 Feb 2012
Cited by 40 | Viewed by 7003
Abstract
Extracellular signal-regulated kinases 1/2 (ERK1/2), components of the mitogen-activated protein kinase (MAPK) signaling cascade, have been recently shown to be involved in synaptic plasticity and in the development of long-term memory in the central nervous system (CNS). We therefore examined the ability of [...] Read more.
Extracellular signal-regulated kinases 1/2 (ERK1/2), components of the mitogen-activated protein kinase (MAPK) signaling cascade, have been recently shown to be involved in synaptic plasticity and in the development of long-term memory in the central nervous system (CNS). We therefore examined the ability of Citrus compounds to activate ERK1/2 in cultured rat cortical neurons, whose activation might have a protective effect against neurodegenerative neurological disorders. Among the samples tested, extracts prepared from the peels of Citrus grandis (Kawachi bankan) were found to have the greatest ability to activate ERK1/2. The active substances were isolated by chromatographic separation, and one of them was identified to be 3,5,6,7,8,3′,4′-heptamethoxyflavone (HMF). HMF significantly induced the phosphorylation of cAMP response element-binding protein (CREB), a downstream target of activated ERK1/2, which appears to be a critical step in the signaling cascade for the structural changes underlying the development of long-term potentiation (LTP). In addition, the administration of HMF into mice treated with NMDA receptor antagonist MK-801 restored the MK-801-induced deterioration of spatial learning performance in the Morris mater-maze task. Taken together, these results suggest that HMF is a neurotrophic agent for treating patients with memory disorders. Full article
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Article
The -308G/A of Tumor Necrosis Factor (TNF)-α and 825C/T of Guanidine Nucleotide Binding Protein 3 (GNB3) are Associated with the Onset of Acute Myocardial Infarction and Obesity in Taiwan
by Wei-To Chang, Yi-Cheng Wang, Chun-Chang Chen, Shi-Kun Zhang, Chen-Hsun Liu, Fu-Hsin Chang and Li-Sung Hsu
Int. J. Mol. Sci. 2012, 13(2), 1846-1857; https://doi.org/10.3390/ijms13021846 - 09 Feb 2012
Cited by 20 | Viewed by 6967
Abstract
Acute myocardial infarction is a highly prevalent cardiovascular disease in Taiwan. Among several etiological risk factors, obesity and inflammation are strongly associated with the frequency of hypertension, cardiovascular disease, diabetes, and myocardial infarction. To discriminate obesity- and inflammation-related genes and the onset of [...] Read more.
Acute myocardial infarction is a highly prevalent cardiovascular disease in Taiwan. Among several etiological risk factors, obesity and inflammation are strongly associated with the frequency of hypertension, cardiovascular disease, diabetes, and myocardial infarction. To discriminate obesity- and inflammation-related genes and the onset of acute myocardial infarction (AMI), a case-control study was conducted to investigate the association of the -308G/A polymorphisms of tumor necrosis factor (TNF)-α and the C825T polymorphism of guanidine nucleotide binding protein 3 (GNB3) with the onset of AMI among Taiwanese cohorts. A total of 103 AMI patients and 163 matched normal control samples were enrolled in the present study. The genomic DNA was extracted and subjected into polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) analysis. An association between the A homozygosity of the TNF-α-308G/A polymorphism and the onset of AMI was observed among the male subjects (p = 0.026; Spearman index = 0.200, p = 0.008). An association between the T homozygosity of GNB3 C825T polymorphism and obesity was also observed (Fisher’s exact, p = 0.009). The TT genotype has a protective effect against acquiring AMI among the obese female population in Taiwan (Fisher’s exact, p = 0.032). In conclusion, TNF-α-308G/A and the GNB3 C825T polymorphisms are associated with obesity and AMI in the Taiwanese population. Full article
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
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Article
Presence of CP4-EPSPS Component in Roundup Ready Soybean-Derived Food Products
by Honghong Wu, Yu Zhang, Changqing Zhu, Xiao Xiao, Xinghu Zhou, Sheng Xu, Wenbiao Shen and Ming Huang
Int. J. Mol. Sci. 2012, 13(2), 1919-1932; https://doi.org/10.3390/ijms13021919 - 10 Feb 2012
Cited by 11 | Viewed by 8204
Abstract
With the widespread use of Roundup Ready soya (event 40-3-2) (RRS), the traceability of transgenic components, especially protein residues, in different soya-related foodstuffs has become an important issue. In this report, transgenic components in commercial soya (including RRS) protein concentrates were firstly detected [...] Read more.
With the widespread use of Roundup Ready soya (event 40-3-2) (RRS), the traceability of transgenic components, especially protein residues, in different soya-related foodstuffs has become an important issue. In this report, transgenic components in commercial soya (including RRS) protein concentrates were firstly detected by using polymerase chain reaction (PCR) and western blot. The results illustrated the different degradation patterns of the cp4-epsps gene and corresponding protein in RRS-derived protein concentrates. Furthermore, western blot was applied to investigate the single factor of food processing and the matrix on the disintegration of CP4-EPSPS protein in RRS powder and soya-derived foodstuffs, and trace the degradation patterns during the food production chain. Our results suggested that the exogenous full length of CP4-EPSPS protein in RRS powder was distinctively sensitive to various heat treatments, including heat, microwave and autoclave (especially), and only one degradation fragment (23.4 kD) of CP4-EPSPS protein was apparently observed when autoclaving was applied. By tracing the protein degradation during RRS-related products, including tofu, tou-kan, and bean curd sheets, however, four degradation fragments (42.9, 38.2, 32.2 and 23.4 kD) were displayed, suggesting that both boiling and bittern adding procedures might have extensive effects on CP4-EPSPS protein degradation. Our results thus confirmed that the distinctive residues of the CP4-EPSPS component could be traced in RRS-related foodstuffs. Full article
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Article
Glucose-Modulated Mitochondria Adaptation in Tumor Cells: A Focus on ATP Synthase and Inhibitor Factor 1
by Rossana Domenis, Elena Bisetto, Davide Rossi, Marina Comelli and Irene Mavelli
Int. J. Mol. Sci. 2012, 13(2), 1933-1950; https://doi.org/10.3390/ijms13021933 - 10 Feb 2012
Cited by 39 | Viewed by 7170
Abstract
Warburg’s hypothesis has been challenged by a number of studies showing that oxidative phosphorylation is repressed in some tumors, rather than being inactive per se. Thus, treatments able to shift energy metabolism by activating mitochondrial pathways have been suggested as an intriguing [...] Read more.
Warburg’s hypothesis has been challenged by a number of studies showing that oxidative phosphorylation is repressed in some tumors, rather than being inactive per se. Thus, treatments able to shift energy metabolism by activating mitochondrial pathways have been suggested as an intriguing basis for the optimization of antitumor strategies. In this study, HepG2 hepatocarcinoma cells were cultivated with different metabolic substrates under conditions mimicking “positive” (activation/biogenesis) or “negative” (silencing) mitochondrial adaptation. In addition to the expected up-regulation of mitochondrial biogenesis, glucose deprivation caused an increase in phosphorylating respiration and a rise in the expression levels of the ATP synthase β subunit and Inhibitor Factor 1 (IF1). Hyperglycemia, on the other hand, led to a markedly decreased level of the transcriptional coactivator PGC-α suggesting down-regulation of mitochondrial biogenesis, although no change in mitochondrial mass and no impairment of phosphorylating respiration were observed. Moreover, a reduction in mitochondrial networking and in ATP synthase dimer stability was produced. No effect on β-ATP synthase expression was elicited. Notably, hyperglycemia caused an increase in IF1 expression levels, but it did not alter the amount of IF1 associated with ATP synthase. These results point to a new role of IF1 in relation to high glucose utilization by tumor cells, in addition to its well known effect upon mitochondrial ATP synthase regulation. Full article
(This article belongs to the Special Issue Molecular System Bioenergetics 2011)
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Article
Bufalin Induces Lung Cancer Cell Apoptosis via the Inhibition of PI3K/Akt Pathway
by Zhitu Zhu, Hongzhi Sun, Guangyou Ma, Zhenghua Wang, Enze Li, Yangyang Liu and Yunpeng Liu
Int. J. Mol. Sci. 2012, 13(2), 2025-2035; https://doi.org/10.3390/ijms13022025 - 14 Feb 2012
Cited by 79 | Viewed by 7601
Abstract
Bufalin is a class of toxic steroids which could induce the differentiation and apoptosis of leukemia cells, and induce the apoptosis of gastric, colon and breast cancer cells. However, the anti-tumor effects of bufalin have not been demonstrated in lung cancer. In this [...] Read more.
Bufalin is a class of toxic steroids which could induce the differentiation and apoptosis of leukemia cells, and induce the apoptosis of gastric, colon and breast cancer cells. However, the anti-tumor effects of bufalin have not been demonstrated in lung cancer. In this study we used A549 human lung adenocarcinoma epithelial cell line as the experimental model to evaluate the potential of bufalin in lung cancer chemotherapy. A549 cells were treated with bufalin, then the proliferation was detected by MTT assay and apoptosis was detected by flow cytometry analysis and Giemsa staining. In addition, A549 cells were treated by Akt inhibitor LY294002 in combination with bufalin and the activation of Akt and Caspase-3 as well as the expression levels of Bax, Bcl-2 and livin were examined by Western blot analysis. The results showed that Bufalin inhibited the proliferation of A549 cells and induced the apoptosis of A549 cells in a dose and time dependent manner. Mechanistically, we found that bufalin inhibited the activation of Akt. Moreover, bufalin synergized with Akt inhibitor to induce the apoptosis of A549 cells and this was associated with the upregulation of Bax expression, the downregulation of Bcl-2 and livin expression, and the activation of Caspase-3. In conclusion, our findings demonstrate that bufalin induces lung cancer cell apoptosis via the inhibition of PI3K/Akt pathway and suggest that bufalin is a potential regimen for combined chemotherapy to overcome the resistance of lung cancer cells to chemotherapeutics induced apoptosis. Full article
(This article belongs to the Section Biochemistry)
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Article
Influence of Post-Treatment with 75% (v/v) Ethanol Vapor on the Properties of SF/P(LLA-CL) Nanofibrous Scaffolds
by Kui-Hua Zhang, Qing Ye and Zhi-Yong Yan
Int. J. Mol. Sci. 2012, 13(2), 2036-2047; https://doi.org/10.3390/ijms13022036 - 14 Feb 2012
Cited by 17 | Viewed by 6421
Abstract
In order to improve the water-resistant ability of silk fibroin (SF) and SF/P(LLA-CL) blended nanofibrous scaffolds for tissue engineering applications, 75% (v/v) ethanol vapor was used to post-treat electrospun nanofibers. SEM indicated that the treated SF and SF/ P(LLA-CL) nanofibrous scaffolds maintained a [...] Read more.
In order to improve the water-resistant ability of silk fibroin (SF) and SF/P(LLA-CL) blended nanofibrous scaffolds for tissue engineering applications, 75% (v/v) ethanol vapor was used to post-treat electrospun nanofibers. SEM indicated that the treated SF and SF/ P(LLA-CL) nanofibrous scaffolds maintained a nanofibrous structure and possessed good water-resistant ability. Characterization of 13C CP-MAS NMR clarified that 75% (v/v) ethanol vapor could induce SF conformation from random coil or α-helix to β-sheet. Although the water contact showed that treated SF/P(LLA-CL) blended nanofibrous scaffolds were hydrophobic, the water uptake demonstrated that their hydrophilicity was greatly superior to those of pure P(LLA-CL) nanofibrous scaffolds. Furthermore, the treated SF/P(LLA-CL) nanofibrous scaffolds, both in dry state and wet state, could retain good mechanical properties. Therefore, 75% (v/v) ethanol vapor treatment might be an ideal method to treat SF and SF/P(LLA-CL) nanofibrous scaffolds for biomedical applications. Full article
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Article
PCR and Magnetic Bead-Mediated Target Capture for the Isolation of Short Interspersed Nucleotide Elements in Fishes
by Dong Liu, Guoli Zhu, Wenqiao Tang, Jinquan Yang and Hongyi Guo
Int. J. Mol. Sci. 2012, 13(2), 2048-2062; https://doi.org/10.3390/ijms13022048 - 15 Feb 2012
Cited by 6 | Viewed by 6508
Abstract
Short interspersed nucleotide elements (SINEs), a type of retrotransposon, are widely distributed in various genomes with multiple copies arranged in different orientations, and cause changes to genes and genomes during evolutionary history. This can provide the basis for determining genome diversity, genetic variation [...] Read more.
Short interspersed nucleotide elements (SINEs), a type of retrotransposon, are widely distributed in various genomes with multiple copies arranged in different orientations, and cause changes to genes and genomes during evolutionary history. This can provide the basis for determining genome diversity, genetic variation and molecular phylogeny, etc. SINE DNA is transcribed into RNA by polymerase III from an internal promoter, which is composed of two conserved boxes, box A and box B. Here we present an approach to isolate novel SINEs based on these promoter elements. Box A of a SINE is obtained via PCR with only one primer identical to box B (B-PCR). Box B and its downstream sequence are acquired by PCR with one primer corresponding to box A (A-PCR). The SINE clone produced by A-PCR is selected as a template to label a probe with biotin. The full-length SINEs are isolated from the genomic pool through complex capture using the biotinylated probe bound to magnetic particles. Using this approach, a novel SINE family, Cn-SINE, from the genomes of Coilia nasus, was isolated. The members are 180–360 bp long. Sequence homology suggests that Cn-SINEs evolved from a leucine tRNA gene. This is the first report of a tRNALeu-related SINE obtained without the use of a genomic library or inverse PCR. These results provide new insights into the origin of SINEs. Full article
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
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Article
ACVR1, a Therapeutic Target of Fibrodysplasia Ossificans Progressiva, Is Negatively Regulated by miR-148a
by Hao Song, Qi Wang, Junge Wen, Shunai Liu, Xuesong Gao, Jun Cheng and Deli Zhang
Int. J. Mol. Sci. 2012, 13(2), 2063-2077; https://doi.org/10.3390/ijms13022063 - 15 Feb 2012
Cited by 36 | Viewed by 13207
Abstract
Fibrodysplasia ossificans progressiva (FOP) is a rare congenital disorder of skeletal malformations and progressive extraskeletal ossification. There is still no effective treatment for FOP. All FOP individuals harbor conserved point mutations in ACVR1 gene that are thought to cause ACVR1 constitutive activation and [...] Read more.
Fibrodysplasia ossificans progressiva (FOP) is a rare congenital disorder of skeletal malformations and progressive extraskeletal ossification. There is still no effective treatment for FOP. All FOP individuals harbor conserved point mutations in ACVR1 gene that are thought to cause ACVR1 constitutive activation and activate BMP signal pathway. The constitutively active ACVR1 is also found to be able to cause endothelial-to-mesenchymal transition (EndMT) in endothelial cells, which may cause the formation of FOP lesions. MicroRNAs (miRNAs) play an essential role in regulating cell differentiation. Here, we verified that miR-148a directly targeted the 3' UTR of ACVR1 mRNA by reporter gene assays and mutational analysis at the miRNA binding sites, and inhibited ACVR1 both at the protein level and mRNA level. Further, we verified that miR-148a could inhibit the mRNA expression of the Inhibitor of DNA binding (Id) gene family thereby suppressing the BMP signaling pathway. This study suggests miR-148a is an important mediator of ACVR1, thus offering a new potential target for the development of therapeutic agents against FOP. Full article
(This article belongs to the Special Issue Non-Coding RNAs)
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Article
Neuroprotective Effects of Pre-Treament with l-Carnitine and Acetyl-l-Carnitine on Ischemic Injury In Vivo and In Vitro
by Rui Zhang, Hong Zhang, Zhongxia Zhang, Tao Wang, Jingya Niu, Dongsheng Cui and Shunjiang Xu
Int. J. Mol. Sci. 2012, 13(2), 2078-2090; https://doi.org/10.3390/ijms13022078 - 15 Feb 2012
Cited by 60 | Viewed by 9177
Abstract
The therapeutic effect of stroke is hampered by the lack of neuroprotective drugs against ischemic insults beyond the acute phase. Carnitine plays important roles in mitochondrial metabolism and in modulating the ratio of coenzyme A (CoA)/acyl-CoA. Here, we investigate the neuroprotective effects of [...] Read more.
The therapeutic effect of stroke is hampered by the lack of neuroprotective drugs against ischemic insults beyond the acute phase. Carnitine plays important roles in mitochondrial metabolism and in modulating the ratio of coenzyme A (CoA)/acyl-CoA. Here, we investigate the neuroprotective effects of l-carnitine (LC) and Acetyl-l-carnitine (ALC) pre-treatment on ischemic insults under the same experimental conditions. We used a transient middle cerebral artery occlusion (MCAO) model to evaluate the protective roles of LC and ALC in acute focal cerebral ischemia in vivo and to understand the possible mechanisms using model of PC12 cell cultures in vitro. Results showed that ALC, but not LC, decreased infarction size in SD rats after MCAO in vivo. However, both LC and ALC pretreatment reduced oxygen-glucose deprivation (OGD)-induced cell injury and decreased OGD-induced cell apoptosis and death in vitro; at the same time, both of them increased the activities of super oxide dismutase (SOD) and ATPase, and decreased the concentration of malondialdehyde (MDA) in vitro. Thus, our findings suggested that LC and ALC pre-treatment are highly effective in the prevention of neuronal cell against ischemic injury in vitro, however, only ALC has the protective effect on neuronal cell injury after ischemia in vivo. Full article
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Article
The Effect of Toll-Like Receptor 4 in the Aqueous Humor of Endotoxin-Induced Uveitis
by Jing Wang, Hong Lu, Yingzhi Xu, Xiaofeng Hu, Wei Chen and Shang Li
Int. J. Mol. Sci. 2012, 13(2), 2110-2118; https://doi.org/10.3390/ijms13022110 - 16 Feb 2012
Cited by 5 | Viewed by 6110
Abstract
In our previous study, we found that acute anterior uveitis (AAU) could be induced in wild-type mice (C3H/HeN), but it could not be induced in TLR4 gene-deficient mice (C3H/HeJ), we concluded that the translocation of transcription factor nuclear factor-κB (NF-κB) may play an [...] Read more.
In our previous study, we found that acute anterior uveitis (AAU) could be induced in wild-type mice (C3H/HeN), but it could not be induced in TLR4 gene-deficient mice (C3H/HeJ), we concluded that the translocation of transcription factor nuclear factor-κB (NF-κB) may play an important role. In this study, we examined the concentration of different cytokines in the aqueous humor of C3H/HeN mice and C3H/HeJ mice with the aim of exploring the role of different cytokines in the lipopolysaccharide (LPS) and TLR4-mediated signal transduction in the development of AAU. Full article
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Article
Correlation Coefficients Between Different Methods of Expressing Bacterial Quantification Using Real Time PCR
by Bahman Navidshad, Juan Boo Liang and Mohammad Faseleh Jahromi
Int. J. Mol. Sci. 2012, 13(2), 2119-2132; https://doi.org/10.3390/ijms13022119 - 16 Feb 2012
Cited by 39 | Viewed by 7750
Abstract
The applications of conventional culture-dependent assays to quantify bacteria populations are limited by their dependence on the inconsistent success of the different culture-steps involved. In addition, some bacteria can be pathogenic or a source of endotoxins and pose a health risk to the [...] Read more.
The applications of conventional culture-dependent assays to quantify bacteria populations are limited by their dependence on the inconsistent success of the different culture-steps involved. In addition, some bacteria can be pathogenic or a source of endotoxins and pose a health risk to the researchers. Bacterial quantification based on the real-time PCR method can overcome the above-mentioned problems. However, the quantification of bacteria using this approach is commonly expressed as absolute quantities even though the composition of samples (like those of digesta) can vary widely; thus, the final results may be affected if the samples are not properly homogenized, especially when multiple samples are to be pooled together before DNA extraction. The objective of this study was to determine the correlation coefficients between four different methods of expressing the output data of real-time PCR-based bacterial quantification. The four methods were: (i) the common absolute method expressed as the cell number of specific bacteria per gram of digesta; (ii) the Livak and Schmittgen, ΔΔCt method; (iii) the Pfaffl equation; and (iv) a simple relative method based on the ratio of cell number of specific bacteria to the total bacterial cells. Because of the effect on total bacteria population in the results obtained using ΔCt-based methods (ΔΔCt and Pfaffl), these methods lack the acceptable consistency to be used as valid and reliable methods in real-time PCR-based bacterial quantification studies. On the other hand, because of the variable compositions of digesta samples, a simple ratio of cell number of specific bacteria to the corresponding total bacterial cells of the same sample can be a more accurate method to quantify the population. Full article
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Article
cDNA Cloning, Overexpression, Purification and Pharmacologic Evaluation for Anticancer Activity of Ribosomal Protein L23A Gene (RPL23A) from the Giant Panda
by Bing Sun, Yi-Ling Hou, Wan-Ru Hou, Si-Nan Zhang, Xiang Ding and Xiu-Lan Su
Int. J. Mol. Sci. 2012, 13(2), 2133-2147; https://doi.org/10.3390/ijms13022133 - 16 Feb 2012
Cited by 12 | Viewed by 8125
Abstract
RPL23A gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L23P family of ribosomal proteins, which is located in the cytoplasm. The purpose of this paper was to explore the structure and anti-cancer function [...] Read more.
RPL23A gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L23P family of ribosomal proteins, which is located in the cytoplasm. The purpose of this paper was to explore the structure and anti-cancer function of ribosomal protein L23A (RPL23A) gene of the Giant Panda (Ailuropoda melanoleuca). The cDNA of RPL23A was cloned successfully from the Giant Panda using RT-PCR technology. We constructed a recombinant expression vector containing RPL23A cDNA and over-expressed it in Escherichia coli using pET28a plasmids. The expression product obtained was purified by using Ni chelating affinity chromatography. Recombinant protein of RPL23A obtained from the experiment acted on Hep-2 cells and human HepG-2 cells, then the growth inhibitory effect of these cells was observed by MTT (3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazolium bromide) assay. The result indicated that the length of the fragment cloned is 506 bp, and it contains an open-reading frame (ORF) of 471 bp encoding 156 amino acids. Primary structure analysis revealed that the molecular weight of the putative RPL23A protein is 17.719 kDa with a theoretical pI 11.16. The molecular weight of the recombinant protein RPL23A is 21.265 kDa with a theoretical pI 10.57. The RPL23A gene can be really expressed in E. coli and the RPL23A protein, fusioned with the N-terminally His-tagged protein, gave rise to the accumulation of an expected 22 KDa polypeptide. The data showed that the recombinant protein RPL23A had a time- and dose-dependency on the cell growth inhibition rate. The data also indicated that the effect at low concentrations was better than at high concentrations on Hep-2 cells, and that the concentration of 0.185 μg/mL had the best rate of growth inhibition of 36.31%. All results of the experiment revealed that the recombinant protein RPL23A exhibited anti-cancer function on the Hep-2 cells. The study provides a scientific basis and aids orientation for the research and development of cancer protein drugs as well as possible anti-cancer mechanisms. Further research is on going to determine the bioactive principle(s) of recombinant protein RPL23A responsible for its anticancer activity. Full article
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Article
Benzyl and Methyl Fatty Hydroxamic Acids Based on Palm Kernel Oil as Chelating Agent for Liquid-Liquid Iron(III) Extraction
by Md Jelas Haron, Hossein Jahangirian, Sidik Silong, Nor Azah Yusof, Anuar Kassim, Roshanak Rafiee-Moghaddam, Behnam Mahdavi, Mazyar Peyda, Yadollah Abdollahi and Jamileh Amin
Int. J. Mol. Sci. 2012, 13(2), 2148-2159; https://doi.org/10.3390/ijms13022148 - 16 Feb 2012
Cited by 9 | Viewed by 7014
Abstract
Liquid-liquid iron(III) extraction was investigated using benzyl fatty hydroxamic acids (BFHAs) and methyl fatty hydroxamic acids (MFHAs) as chelating agents through the formation of iron(III) methyl fatty hydroxamate (Fe-MFHs) or iron(III) benzyl fatty hydroxamate (Fe-BFHs) in the organic phase. The results obtained under [...] Read more.
Liquid-liquid iron(III) extraction was investigated using benzyl fatty hydroxamic acids (BFHAs) and methyl fatty hydroxamic acids (MFHAs) as chelating agents through the formation of iron(III) methyl fatty hydroxamate (Fe-MFHs) or iron(III) benzyl fatty hydroxamate (Fe-BFHs) in the organic phase. The results obtained under optimized conditions, showed that the chelating agents in hexane extract iron(III) at pH 1.9 were realized effectively with a high percentage of extraction (97.2% and 98.1% for MFHAs and BFHAs, respectively). The presence of a large amount of Mg(II), Ni(II), Al(III), Mn(II) and Co(II) ions did affect the iron(III) extraction. Finally stripping studies for recovering iron(III) from organic phase (Fe-MFHs or Fe-BFHs dissolved in hexane) were carried out at various concentrations of HCl, HNO3 and H2SO4. The results showed that the desired acid for recovery of iron(III) was 5 M HCl and quantitative recovery of iron(III) was achieved from Fe(III)-MFHs and Fe(III)-BFHs solutions in hexane containing 5 mg/L of Fe(III). Full article
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Article
On the Electrophilic Character of Molecules Through Its Relation with Electronegativity and Chemical Hardness
by Nazmul Islam and Dulal C. Ghosh
Int. J. Mol. Sci. 2012, 13(2), 2160-2175; https://doi.org/10.3390/ijms13022160 - 17 Feb 2012
Cited by 38 | Viewed by 7207
Abstract
Electrophilicity is an intrinsic property of atoms and molecules. It probably originates logistically with the involvement in the physical process of electrostatics of soaked charge in electronic shells and the screened nuclear charge of atoms. Motivated by the existing view of conceptual density [...] Read more.
Electrophilicity is an intrinsic property of atoms and molecules. It probably originates logistically with the involvement in the physical process of electrostatics of soaked charge in electronic shells and the screened nuclear charge of atoms. Motivated by the existing view of conceptual density functional theory that similar to electronegativity and hardness equalization, there should be a physical process of equalization of electrophilicity during the chemical process of formation of hetero nuclear molecules, we have developed a new theoretical scheme and formula for evaluating the electrophilicity of hetero nuclear molecules. A comparative study with available bench marking reveals that the hypothesis of electrophilicity and equalization, and the present method of evaluating equalized electrophilicity, are scientifically promising. Full article
(This article belongs to the Special Issue Atoms in Molecules and in Nanostructures)
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Article
Computational Studies of Difference in Binding Modes of Peptide and Non-Peptide Inhibitors to MDM2/MDMX Based on Molecular Dynamics Simulations
by Jianzhong Chen, Dinglin Zhang, Yuxin Zhang and Guohui Li
Int. J. Mol. Sci. 2012, 13(2), 2176-2195; https://doi.org/10.3390/ijms13022176 - 17 Feb 2012
Cited by 21 | Viewed by 8174
Abstract
Inhibition of p53-MDM2/MDMX interaction is considered to be a promising strategy for anticancer drug design to activate wild-type p53 in tumors. We carry out molecular dynamics (MD) simulations to study the binding mechanisms of peptide and non-peptide inhibitors to MDM2/MDMX. The rank of [...] Read more.
Inhibition of p53-MDM2/MDMX interaction is considered to be a promising strategy for anticancer drug design to activate wild-type p53 in tumors. We carry out molecular dynamics (MD) simulations to study the binding mechanisms of peptide and non-peptide inhibitors to MDM2/MDMX. The rank of binding free energies calculated by molecular mechanics generalized Born surface area (MM-GBSA) method agrees with one of the experimental values. The results suggest that van der Waals energy drives two kinds of inhibitors to MDM2/MDMX. We also find that the peptide inhibitors can produce more interaction contacts with MDM2/MDMX than the non-peptide inhibitors. Binding mode predictions based on the inhibitor-residue interactions show that the π–π, CH–π and CH–CH interactions dominated by shape complimentarity, govern the binding of the inhibitors in the hydrophobic cleft of MDM2/MDMX. Our studies confirm the residue Tyr99 in MDMX can generate a steric clash with the inhibitors due to energy and structure. This finding may theoretically provide help to develop potent dual-specific or MDMX inhibitors. Full article
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Article
Using Support Vector Machine and Evolutionary Profiles to Predict Antifreeze Protein Sequences
by Xiaowei Zhao, Zhiqiang Ma and Minghao Yin
Int. J. Mol. Sci. 2012, 13(2), 2196-2207; https://doi.org/10.3390/ijms13022196 - 17 Feb 2012
Cited by 39 | Viewed by 6877
Abstract
Antifreeze proteins (AFPs) are ice-binding proteins. Accurate identification of new AFPs is important in understanding ice-protein interactions and creating novel ice-binding domains in other proteins. In this paper, an accurate method, called AFP_PSSM, has been developed for predicting antifreeze proteins using a support [...] Read more.
Antifreeze proteins (AFPs) are ice-binding proteins. Accurate identification of new AFPs is important in understanding ice-protein interactions and creating novel ice-binding domains in other proteins. In this paper, an accurate method, called AFP_PSSM, has been developed for predicting antifreeze proteins using a support vector machine (SVM) and position specific scoring matrix (PSSM) profiles. This is the first study in which evolutionary information in the form of PSSM profiles has been successfully used for predicting antifreeze proteins. Tested by 10-fold cross validation and independent test, the accuracy of the proposed method reaches 82.67% for the training dataset and 93.01% for the testing dataset, respectively. These results indicate that our predictor is a useful tool for predicting antifreeze proteins. A web server (AFP_PSSM) that implements the proposed predictor is freely available. Full article
(This article belongs to the Section Biochemistry)
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330 KiB  
Article
A Novel LMP1 Antibody Synergizes with Mitomycin C to Inhibit Nasopharyngeal Carcinoma Growth in Vivo Through Inducing Apoptosis and Downregulating Vascular Endothelial Growth Factor
by Yuan Mao, Da-Wei Zhang, Juan Wen, Qing Cao, Ren-Jie Chen, Jin Zhu and Zhen-Qing Feng
Int. J. Mol. Sci. 2012, 13(2), 2208-2218; https://doi.org/10.3390/ijms13022208 - 17 Feb 2012
Cited by 22 | Viewed by 7881
Abstract
Combined therapy emerges as an attractive strategy for cancer treatment. The aim of this study was to investigate the inhibitory effects of mitomycin C (MMC) combined with a novel antibody fragment (Fab) targeting latent membrane protein 1 (LMP1) on nasopharyngeal carcinoma (NPC) xenograft [...] Read more.
Combined therapy emerges as an attractive strategy for cancer treatment. The aim of this study was to investigate the inhibitory effects of mitomycin C (MMC) combined with a novel antibody fragment (Fab) targeting latent membrane protein 1 (LMP1) on nasopharyngeal carcinoma (NPC) xenograft nude mice. The inhibitory rates of MMC (2 mg/kg), Fab (4 mg/kg), MMC (2 mg/kg) + Fab (4 mg/kg), and MMC (1 mg/kg) + Fab (4 mg/kg) were 20.1%, 7.3%, 42.5% and 40.5%, respectively. Flow cytometry analysis showed that the apoptotic rate of xenograft tumor cells in the MMC and Fab combination group was 28 ± 4.12%, significantly higher than the MMC (2 mg/kg) group (P < 0.01). Immunohistochemical staining showed that VEGF expression in NPC xenografts was significantly inhibited in the combination group compared to the Fab (4 mg/kg) group (P < 0.05). In conclusion, both MMC and Fab could inhibit NPC xenograft tumor growth in vivo and combination therapy showed apparent synergistic anti-tumor effects, which may be due to the induction of tumor cell apoptosis and the downregulation of VEGF expression. These results suggest that the novel combined therapy utilizing traditional chemotherapeutics and antibody-targeted therapy could be a promising strategy for the treatment of NPC. Full article
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Article
Nanosecond T-Jump Experiment in Poly(glutamic acid): A Circular Dichroism Study
by Lucille Mendonça and François Hache
Int. J. Mol. Sci. 2012, 13(2), 2239-2248; https://doi.org/10.3390/ijms13022239 - 17 Feb 2012
Cited by 13 | Viewed by 7597
Abstract
Poly(glutamic acid) has been studied with a nanosecond T-jump experiment. A new experimental set-up based on the frequency-quadrupling of an 82 MHz Titanium-Sapphire laser allows rapid CD measurements to be performed. Combining time-resolved absorption and circular dichroism at 204 and 220 nm, we [...] Read more.
Poly(glutamic acid) has been studied with a nanosecond T-jump experiment. A new experimental set-up based on the frequency-quadrupling of an 82 MHz Titanium-Sapphire laser allows rapid CD measurements to be performed. Combining time-resolved absorption and circular dichroism at 204 and 220 nm, we are able to measure precisely the unfolding relaxation time as well as the helical fraction evolution. We show that only CD at 220 nm is relevant to observe the unfolding of an alpha helix whereas no change is observed for CD at 204 nm. Conversely, both absorptions yield information on the dynamics of the process. Full article
(This article belongs to the Special Issue Applications of Circular Dichroism)
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Article
Seasonal Variations of the Antioxidant Composition in Ground Bamboo Sasa argenteastriatus Leaves
by Qinxue Ni, Guangzhi Xu, Zhiqiang Wang, Qianxin Gao, Shu Wang and Youzuo Zhang
Int. J. Mol. Sci. 2012, 13(2), 2249-2262; https://doi.org/10.3390/ijms13022249 - 20 Feb 2012
Cited by 42 | Viewed by 7810
Abstract
Sasa argenteastriatus, with abundant active compounds and high antioxidant activity in leaves, is a new leafy bamboo grove suitable for exploitation. To utilize it more effectively and scientifically, we investigate the seasonal variations of antioxidant composition in its leaves and antioxidant activity. [...] Read more.
Sasa argenteastriatus, with abundant active compounds and high antioxidant activity in leaves, is a new leafy bamboo grove suitable for exploitation. To utilize it more effectively and scientifically, we investigate the seasonal variations of antioxidant composition in its leaves and antioxidant activity. The leaves of Sasa argenteastriatus were collected on the 5th day of each month in three same-sized sample plots from May 2009 to May 2011. The total flavonoids (TF): phenolics (TP) and triterpenoid (TT) of bamboo leaves were extracted and the contents analyzed by UV-spectrophotometer. Our data showed that all exhibited variations with the changing seasons, with the highest levels appearing in November to March. Antioxidant activity was measured using DPPH and FRAP methods. The highest antioxidant activity appeared in December with the lowest in May. Correlation analyses demonstrated that TP and TF exhibited high correlation with bamboo antioxidant activity. Eight bamboo characteristic compounds (orientin, isoorientin, vitexin, homovitexin and p-coumaric acid, chlorogenic acid, caffeic acid, ferulic acid) were determined by RP-HPLC synchronously. We found that chlorogenic acid, isoorientin and vitexin are the main compounds in Sasa argenteastriatus leaves and the content of isovitexin and chlorogenic acid showed a similar seasonal variation with the TF, TP and TT. Our results suggested that the optimum season for harvesting Sasa argenteastriatus leaves is between autumn and winter. Full article
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Article
Comprehensive and Facile Synthesis of Some Functionalized Bis-Heterocyclic Compounds Containing a Thieno[2,3-b]thiophene Motif
by Yahia N. Mabkhot, Assem Barakat, Abdullah M. Al-Majid and Saeed A. Alshahrani
Int. J. Mol. Sci. 2012, 13(2), 2263-2275; https://doi.org/10.3390/ijms13022263 - 20 Feb 2012
Cited by 21 | Viewed by 6578
Abstract
A comprehensive and facile method for the synthesis of new functionalized bis-heterocyclic compounds containing a thieno[2,3-b]thiophene motif is described. The hitherto unknown bis-pyrazolothieno[2,3-b]thiophene derivatives 2ac, bis-pyridazin othieno[2,3-b]thiophene derivatives 4, bis-pyridinothieno[2,3-b]thiophene derivatives [...] Read more.
A comprehensive and facile method for the synthesis of new functionalized bis-heterocyclic compounds containing a thieno[2,3-b]thiophene motif is described. The hitherto unknown bis-pyrazolothieno[2,3-b]thiophene derivatives 2ac, bis-pyridazin othieno[2,3-b]thiophene derivatives 4, bis-pyridinothieno[2,3-b]thiophene derivatives 6a,b, and to an analogous bis-pyridinothieno[2,3-b]thiophene nitrile derivatives 7 are obtained. Additionally, the novel bis-pyradazinonothieno[2,3-b]thiophene derivatives 9, and nicotinic acid derivatives 10, 11 are obtained via bis-dienamide 8. The structures of all newly synthesized compounds have been elucidated by 1H, 13C NMR, GCMS, and IR spectrometry. These compounds represent a new class of sulfur and Nitrogen containing heterocycles that should also be of interest as new materials. Full article
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Article
Emodin Prevents Intrahepatic Fat Accumulation, Inflammation and Redox Status Imbalance During Diet-Induced Hepatosteatosis in Rats
by Anna Alisi, Anna Pastore, Sara Ceccarelli, Nadia Panera, Daniela Gnani, Giovannella Bruscalupi, Mara Massimi, Giulia Tozzi, Fiorella Piemonte and Valerio Nobili
Int. J. Mol. Sci. 2012, 13(2), 2276-2289; https://doi.org/10.3390/ijms13022276 - 20 Feb 2012
Cited by 52 | Viewed by 8161
Abstract
High-fat and/or high-carbohydrate diets may predispose to several metabolic disturbances including liver fatty infiltration (hepatosteatosis) or be associated with necro-inflammation and fibrosis (steatohepatitis). Several studies have emphasized the hepatoprotective effect of some natural agents. In this study, we investigated the potential therapeutic effects [...] Read more.
High-fat and/or high-carbohydrate diets may predispose to several metabolic disturbances including liver fatty infiltration (hepatosteatosis) or be associated with necro-inflammation and fibrosis (steatohepatitis). Several studies have emphasized the hepatoprotective effect of some natural agents. In this study, we investigated the potential therapeutic effects of the treatment with emodin, an anthraquinone derivative with anti-oxidant and anti-cancer abilities, in rats developing diet-induced hepatosteatosis and steatohepatitis. Sprague-Dawley rats were fed a standard diet (SD) for 15 weeks, or a high-fat/high-fructose diet (HFD/HF). After 5 weeks, emodin was added to the drinking water of some of the SD and HFD/HF rats. The experiment ended after an additional 10 weeks. Emodin-treated HFD/HF rats were protected from hepatosteatosis and metabolic derangements usually observed in HFD/HF animals. Furthermore, emodin exerted anti-inflammatory activity by inhibiting the HFD/HF-induced increase of tumor necrosis factor (TNF)-α. Emodin also affected the hepatocytes glutathione homeostasis and levels of the HFD/HF-induced increase of glutathionylated/phosphorylated phosphatase and tensin homolog (PTEN). In conclusion, we demonstrated that a natural agent such as emodin can prevent hepatosteatosis, preserving liver from pro-inflammatory and pro-oxidant damage caused by HFD/HF diet. These findings are promising, proposing emodin as a possible hindrance to progression of hepatosteatosis into steatohepatitis. Full article
(This article belongs to the Special Issue Antioxidants)
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Article
In Vitro Control of Post-Harvest Fruit Rot Fungi by Some Plant Essential Oil Components
by Ippolito Camele, Luciana Altieri, Laura De Martino, Vincenzo De Feo, Emilia Mancini and Gian Luigi Rana
Int. J. Mol. Sci. 2012, 13(2), 2290-2300; https://doi.org/10.3390/ijms13022290 - 21 Feb 2012
Cited by 76 | Viewed by 10068
Abstract
Eight substances that are main components of the essential oils from three Mediterranean aromatic plants (Verbena officinalis, Thymus vulgaris and Origanum vulgare), previously found active against some phytopathogenic Fungi and Stramenopila, have been tested in vitro against five etiological agents [...] Read more.
Eight substances that are main components of the essential oils from three Mediterranean aromatic plants (Verbena officinalis, Thymus vulgaris and Origanum vulgare), previously found active against some phytopathogenic Fungi and Stramenopila, have been tested in vitro against five etiological agents of post-harvest fruit decay, Botrytis cinerea, Penicillium italicum, P. expansum, Phytophthora citrophthora and Rhizopus stolonifer. The tested compounds were β-fellandrene, β-pinene, camphene, carvacrol, citral, o-cymene, γ-terpinene and thymol. Citral exhibited a fungicidal action against P. citrophthora; carvacrol and thymol showed a fungistatic activity against P. citrophthora and R. stolonifer. Citral and carvacrol at 250 ppm, and thymol at 150 and 250 ppm stopped the growth of B. cinerea. Moreover, thymol showed fungistatic and fungicidal action against P. italicum. Finally, the mycelium growth of P. expansum was inhibited in the presence of 250 ppm of thymol and carvacrol. These results represent an important step toward the goal to use some essential oils or their components as natural preservatives for fruits and foodstuffs, due to their safety for consumer healthy and positive effect on shelf life extension of agricultural fresh products. Full article
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Article
Expression Patterns of Genes Involved in the Defense and Stress Response of Spiroplasma citri Infected Madagascar Periwinkle Catharanthus roseus
by Naghmeh Nejat, Ganesan Vadamalai and Matthew Dickinson
Int. J. Mol. Sci. 2012, 13(2), 2301-2313; https://doi.org/10.3390/ijms13022301 - 21 Feb 2012
Cited by 14 | Viewed by 6485
Abstract
Madagascar periwinkle is an ornamental and a medicinal plant, and is also an indicator plant that is highly susceptible to phytoplasma and spiroplasma infections from different crops. Periwinkle lethal yellows, caused by Spiroplasma citri, is one of the most devastating diseases of [...] Read more.
Madagascar periwinkle is an ornamental and a medicinal plant, and is also an indicator plant that is highly susceptible to phytoplasma and spiroplasma infections from different crops. Periwinkle lethal yellows, caused by Spiroplasma citri, is one of the most devastating diseases of periwinkle. The response of plants to S. citri infection is very little known at the transcriptome level. In this study, quantitative real-time PCR (RT-qPCR) was used to investigate the expression levels of four selected genes involved in defense and stress responses in naturally and experimentally Spiroplasma citri infected periwinkles. Strictosidine β-glucosidase involved in terpenoid indole alkaloids (TIAs) biosynthesis pathway showed significant upregulation in experimentally and naturally infected periwinkles. The transcript level of extensin increased in leaves of periwinkles experimentally infected by S. citri in comparison to healthy ones. A similar level of heat shock protein 90 and metallothionein expression was observed in healthy, naturally and experimentally spiroplasma-diseased periwinkles. Overexpression of Strictosidine β-glucosidase demonstrates the potential utility of this gene as a host biomarker to increase the fidelity of S. citri detection and can also be used in breeding programs to develop stable disease-resistance varieties. Full article
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
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Article
Antioxidant and Hepatoprotective Effects of the Red Ginseng Essential Oil in H2O2-Treated HepG2 Cells and CCl4-Treated Mice
by Min-Ji Bak, Mira Jun and Woo-Sik Jeong
Int. J. Mol. Sci. 2012, 13(2), 2314-2330; https://doi.org/10.3390/ijms13022314 - 21 Feb 2012
Cited by 99 | Viewed by 11905
Abstract
The aim of this study was to evaluate the antioxidant mechanisms of red ginseng essential oil (REO) in cells as well as in an animal model. REO was prepared by a supercritical CO2 extraction of waste-products generated after hot water extraction of [...] Read more.
The aim of this study was to evaluate the antioxidant mechanisms of red ginseng essential oil (REO) in cells as well as in an animal model. REO was prepared by a supercritical CO2 extraction of waste-products generated after hot water extraction of red ginseng. In HepG2 cells, REO diminished the H2O2-mediated oxidative stress and also restored both the activity and expression of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase. Administration of REO inhibited the phosphorylation of upstream mitogen-activated protein kinases (MAPKs) such as c-Jun N-terminal kinase, extracellular signal-regulated kinase, and p38. In mice, the CCl4-mediated elevation of serum aspartate transaminase and alanine transaminase as well as the induction of hepatic lipid peroxidation were decreased by REO administration. REO treatments also resulted in up-regulation of the antioxidant enzyme expression in the liver. Moreover, increased phosphorylations of MAPKs were inhibited after REO administration. Overall, REO seems to protect the liver from oxidative stress through the activation and induction of antioxidant enzymes via inhibition of MAPKs pathways. Full article
(This article belongs to the Special Issue Advances in Nutraceutical Research)
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601 KiB  
Article
Supercritical Carbon Dioxide Extraction of the Oak Silkworm (Antheraea pernyi) Pupal Oil: Process Optimization and Composition Determination
by Wen-Juan Pan, Ai-Mei Liao, Jian-Guo Zhang, Zeng Dong and Zhao-Jun Wei
Int. J. Mol. Sci. 2012, 13(2), 2354-2367; https://doi.org/10.3390/ijms13022354 - 21 Feb 2012
Cited by 35 | Viewed by 8124
Abstract
Supercritical carbon dioxide (SC-CO2) extraction of oil from oak silkworm pupae was performed in the present research. Response surface methodology (RSM) was applied to optimize the parameters of SC-CO2 extraction, including extraction pressure, temperature, time and CO2 flow rate [...] Read more.
Supercritical carbon dioxide (SC-CO2) extraction of oil from oak silkworm pupae was performed in the present research. Response surface methodology (RSM) was applied to optimize the parameters of SC-CO2 extraction, including extraction pressure, temperature, time and CO2 flow rate on the yield of oak silkworm pupal oil (OSPO). The optimal extraction condition for oil yield within the experimental range of the variables researched was at 28.03 MPa, 1.83 h, 35.31 °C and 20.26 L/h as flow rate of CO2. Under this condition, the oil yield was predicted to be 26.18%. The oak silkworm pupal oil contains eight fatty acids, and is rich in unsaturated fatty acids and α-linolenic acid (ALA), accounting for 77.29% and 34.27% in the total oil respectively. Full article
(This article belongs to the Special Issue Supercritical Fluid Extraction)
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Article
Pyrrolo[3,2-d]pyrimidine Derivatives as Type II Kinase Insert Domain Receptor (KDR) Inhibitors: CoMFA and CoMSIA Studies
by Xiao-Yun Wu, Wen-Hua Chen, Shu-Guang Wu, Yuan-Xin Tian and Jia-Jie Zhang
Int. J. Mol. Sci. 2012, 13(2), 2387-2404; https://doi.org/10.3390/ijms13022387 - 22 Feb 2012
Cited by 10 | Viewed by 6593
Abstract
Kinase insert domain receptor (KDR) inhibitors have been proved to be very effective anticancer agents. Molecular docking, 3D-QSAR methods, CoMFA and CoMSIA were performed on pyrrolo[3,2-d]pyrimidine derivatives as non-ATP competitive KDR inhibitors (type II). The bioactive conformation was explored by docking [...] Read more.
Kinase insert domain receptor (KDR) inhibitors have been proved to be very effective anticancer agents. Molecular docking, 3D-QSAR methods, CoMFA and CoMSIA were performed on pyrrolo[3,2-d]pyrimidine derivatives as non-ATP competitive KDR inhibitors (type II). The bioactive conformation was explored by docking one potent compound 20 into the active site of KDR in its DFG-out inactive conformation. The constructed CoMFA and CoMSIA models produced statistically significant results with the cross-validated correlation coefficients q2 of 0.542 and 0.552, non-cross-validated correlation coefficients r2 of 0.912 and 0.955, and predicted correction coefficients r2pred of 0.913 and 0.897, respectively. These results ensure the CoMFA and CoMSIA models as a tool to guide the design of a series of new potent KDR inhibitors. Full article
(This article belongs to the Section Physical Chemistry, Theoretical and Computational Chemistry)
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318 KiB  
Article
Characterization of Different Functionalized Lipidic Nanocapsules as Potential Drug Carriers
by Paola Sánchez-Moreno, Juan Luis Ortega-Vinuesa, Antonio Martín-Rodríguez, Houría Boulaiz, Juan Antonio Marchal-Corrales and José Manuel Peula-García
Int. J. Mol. Sci. 2012, 13(2), 2405-2424; https://doi.org/10.3390/ijms13022405 - 22 Feb 2012
Cited by 39 | Viewed by 9092
Abstract
Lipid nanocapsules (LNC) based on a core-shell structure consisting of an oil-filled core with a surrounding polymer layer are known to be promising vehicles for the delivery of hydrophobic drugs in the new therapeutic strategies in anti-cancer treatments. The present work has been [...] Read more.
Lipid nanocapsules (LNC) based on a core-shell structure consisting of an oil-filled core with a surrounding polymer layer are known to be promising vehicles for the delivery of hydrophobic drugs in the new therapeutic strategies in anti-cancer treatments. The present work has been designed as basic research about different LNC systems. We have synthesized—and physico-chemically characterized—three different LNC systems in which the core was constituted by olive oil and the shell by different phospholipids (phosphatidyl-serine or lecithin) and other biocompatible molecules such as Pluronic® F68 or chitosan. It is notable that the olive-oil-phosphatidyl-serine LCN is a novel formulation presented in this work and was designed to generate an enriched carboxylic surface. This carboxylic layer is meant to link specific antibodies, which could facilitate the specific nanocapsule uptake by cancer cells. This is why nanoparticles with phosphatidyl-serine in their shell have also been used in this work to form immuno-nanocapsules containing a polyclonal IgG against a model antigen (C-reactive protein) covalently bounded by means of a simple and reproducible carbodiimide method. An immunological study was made to verify that these IgG-LNC complexes showed the expected specific immune response. Finally, a preliminary in vitro study was performed by culturing a breast-carcinoma cell line (MCF-7) with Nile-Red-loaded LNC. We found that these cancer cells take up the fluorescent Nile-Red molecule in a process dependent on the surface properties of the nanocarriers. Full article
(This article belongs to the Special Issue From Molecules to Nanomaterials)
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364 KiB  
Article
DNA Barcodes of Asian Houbara Bustard (Chlamydotis undulata macqueenii)
by Ibrahim A. Arif, Haseeb A. Khan, Joseph B. Williams, Mohammad Shobrak and Waad I. Arif
Int. J. Mol. Sci. 2012, 13(2), 2425-2438; https://doi.org/10.3390/ijms13022425 - 22 Feb 2012
Cited by 5 | Viewed by 7574
Abstract
Populations of Houbara Bustards have dramatically declined in recent years. Captive breeding and reintroduction programs have had limited success in reviving population numbers and thus new technological solutions involving molecular methods are essential for the long term survival of this species. In this [...] Read more.
Populations of Houbara Bustards have dramatically declined in recent years. Captive breeding and reintroduction programs have had limited success in reviving population numbers and thus new technological solutions involving molecular methods are essential for the long term survival of this species. In this study, we sequenced the 694 bp segment of COI gene of the four specimens of Asian Houbara Bustard (Chlamydotis undulata macqueenii). We also compared these sequences with earlier published barcodes of 11 individuals comprising different families of the orders Gruiformes, Ciconiiformes, Podicipediformes and Crocodylia (out group). The pair-wise sequence comparison showed a total of 254 variable sites across all the 15 sequences from different taxa. Three of the four specimens of Houbara Bustard had an identical sequence of COI gene and one individual showed a single nucleotide difference (G > A transition at position 83). Within the bustard family (Otididae), comparison among the three species (Asian Houbara Bustard, Great Bustard (Otis tarda) and the Little Bustard (Tetrax tetrax)), representing three different genera, showed 116 variable sites. For another family (Rallidae), the intra-family variable sites among the individuals of four different genera were found to be 146. The COI genetic distances among the 15 individuals varied from 0.000 to 0.431. Phylogenetic analysis using 619 bp nucleotide segment of COI clearly discriminated all the species representing different genera, families and orders. All the four specimens of Houbara Bustard formed a single clade and are clearly separated from other two individuals of the same family (Otis tarda and Tetrax tetrax). The nucleotide sequence of partial segment of COI gene effectively discriminated the closely related species. This is the first study reporting the barcodes of Houbara Bustard and would be helpful in future molecular studies, particularly for the conservation of this threatened bird in Saudi Arabia. Full article
(This article belongs to the Section Biochemistry)
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Article
Enhancing Osteoconduction of PLLA-Based Nanocomposite Scaffolds for Bone Regeneration Using Different Biomimetic Signals to MSCs
by Gabriela Ciapetti, Donatella Granchi, Valentina Devescovi, Serena R. Baglio, Elisa Leonardi, Desirèe Martini, Maria Jesus Jurado, Beatriz Olalde, Ilaria Armentano, Josè M. Kenny, Frank X. Walboomers, Josè Inaki Alava and Nicola Baldini
Int. J. Mol. Sci. 2012, 13(2), 2439-2458; https://doi.org/10.3390/ijms13022439 - 22 Feb 2012
Cited by 36 | Viewed by 9429
Abstract
In bone engineering, the adhesion, proliferation and differentiation of mesenchymal stromal cells rely on signaling from chemico-physical structure of the substrate, therefore prompting the design of mimetic “extracellular matrix”-like scaffolds. In this study, three-dimensional porous poly-L-lactic acid (PLLA)-based scaffolds have been mixed with [...] Read more.
In bone engineering, the adhesion, proliferation and differentiation of mesenchymal stromal cells rely on signaling from chemico-physical structure of the substrate, therefore prompting the design of mimetic “extracellular matrix”-like scaffolds. In this study, three-dimensional porous poly-L-lactic acid (PLLA)-based scaffolds have been mixed with different components, including single walled carbon nanotubes (CNT), micro-hydroxyapatite particles (HA), and BMP2, and treated with plasma (PT), to obtain four different nanocomposites: PLLA + CNT, PLLA + CNTHA, PLLA + CNT + HA + BMP2 and PLLA + CNT + HA + PT. Adult bone marrow mesenchymal stromal cells (MSCs) were derived from the femur of orthopaedic patients, seeded on the scaffolds and cultured under osteogenic induction up to differentiation and mineralization. The release of specific metabolites and temporal gene expression profiles of marrow-derived osteoprogenitors were analyzed at definite time points, relevant to in vitro culture as well as in vivo differentiation. As a result, the role of the different biomimetic components added to the PLLA matrix was deciphered, with BMP2-added scaffolds showing the highest biomimetic activity on cells differentiating to mature osteoblasts. The modification of a polymeric scaffold with reinforcing components which also work as biomimetic cues for cells can effectively direct osteoprogenitor cells differentiation, so as to shorten the time required for mineralization. Full article
(This article belongs to the Special Issue Composite Materials in Skeletal Engineering)
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376 KiB  
Article
First Insights on Organic Cosolvent Effects on FhuA Wildtype and FhuA Δ1-159
by Stefanie-Joana Tenne and Ulrich Schwaneberg
Int. J. Mol. Sci. 2012, 13(2), 2459-2471; https://doi.org/10.3390/ijms13022459 - 22 Feb 2012
Cited by 19 | Viewed by 6575
Abstract
Circular dichroism (CD) and deconvolution were used to study the structural integrity of a “plugged” and an “open” FhuA transmembrane channel protein in the presence of varied concentrations of tetrahydrofuran (THF), ethanol (EtOH) and chloroform/methanol (C/M). FhuA is an Escherichia coli outer membrane [...] Read more.
Circular dichroism (CD) and deconvolution were used to study the structural integrity of a “plugged” and an “open” FhuA transmembrane channel protein in the presence of varied concentrations of tetrahydrofuran (THF), ethanol (EtOH) and chloroform/methanol (C/M). FhuA is an Escherichia coli outer membrane protein (78.9 kDa) consisting of 22 β-sheets and an internal globular cork domain which acts as an iron transporter. FhuA and the deletion variant FhuA Δ1-159 showed comparable and remarkable resistance in the presence of THF (≤40 vol%) and EtOH (≤10 vol%). In C/M, significant differences in structural resistance were observed (FhuA stable ≤10 vol%; FhuA Δ1-159 ≤1 vol%). Deconvolution of CD-spectra for FhuA and FhuA Δ1-159 yielded β-sheet contents of 61 % (FhuA) and 58% (FhuA Δ1-159). Interestingly, FhuA and FhuA Δ1-159 had comparable β-sheet contents in the presence and absence of all three organic cosolvents. Additionally, precipitated FhuA and FhuA Δ1-159 (in 40 vol% C/M or 65 vol% THF) redissolved by supplementing the detergent n-octyl-oligo-oxyethylene (oPOE). Full article
(This article belongs to the Special Issue Applications of Circular Dichroism)
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Article
Antioxidant Activity of Mulberry Fruit Extracts
by Muhammad Arfan, Rasool Khan, Anna Rybarczyk and Ryszard Amarowicz
Int. J. Mol. Sci. 2012, 13(2), 2472-2480; https://doi.org/10.3390/ijms13022472 - 22 Feb 2012
Cited by 98 | Viewed by 12456
Abstract
Phenolic compounds were extracted from the fruits of Morus nigra and Morus alba using methanol and acetone. The sugar-free extracts (SFEs) were prepared using Amberlite XAD-16 column chromatography. All of the SFEs exhibited antioxidant potential as determined by ABTS (0.75–1.25 mmol Trolox/g), DPPH [...] Read more.
Phenolic compounds were extracted from the fruits of Morus nigra and Morus alba using methanol and acetone. The sugar-free extracts (SFEs) were prepared using Amberlite XAD-16 column chromatography. All of the SFEs exhibited antioxidant potential as determined by ABTS (0.75–1.25 mmol Trolox/g), DPPH (2,2-diphenyl-1-picrylhydrazyl) (EC50 from 48 μg/mL to 79 μg/mL), and reducing power assays. However, a stronger activity was noted for the SFEs obtained from Morus nigra fruits. These extracts also possessed the highest contents of total phenolics: 164 mg/g (methanolic SFE) and 173 mg/g (acetonic SFE). The presence of phenolic acids and flavonoids in the extracts was confirmed using HPLC method and chlorogenic acid and rutin were found as the dominant phenolic constituents in the SFEs. Full article
(This article belongs to the Special Issue Antioxidants)
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2256 KiB  
Article
The Expression Profiling of the Lipoxygenase (LOX) Family Genes During Fruit Development, Abiotic Stress and Hormonal Treatments in Cucumber (Cucumis sativus L.)
by Xue-Yong Yang, Wei-Jie Jiang and Hong-Jun Yu
Int. J. Mol. Sci. 2012, 13(2), 2481-2500; https://doi.org/10.3390/ijms13022481 - 22 Feb 2012
Cited by 92 | Viewed by 11071
Abstract
Lipoxygenases (LOXs) are non-haem iron-containing dioxygenases that catalyse oxygenation of polyunsaturated fatty acids and lipids to initiate the formation of a group of biologically active compounds called oxylipins. Plant oxylipins play important and diverse functions in the cells. In the current study, expression [...] Read more.
Lipoxygenases (LOXs) are non-haem iron-containing dioxygenases that catalyse oxygenation of polyunsaturated fatty acids and lipids to initiate the formation of a group of biologically active compounds called oxylipins. Plant oxylipins play important and diverse functions in the cells. In the current study, expression analysis during cucumber development using semi-quantitative RT-PCR revealed that 13 of 23 CsLOX genes were detectable, and were tissue specific or preferential accumulation. In total, 12 genes were found to be differentially expressed during fruit development and have different patterns of expression in exocarp, endocarp and pulp at day 5 after anthesis. The expression analysis of these 12 cucumber LOX genes in response to abiotic stresses and plant growth regulator treatments revealed their differential transcript in response to more than one treatment, indicating their diverse functions in abiotic stress and hormone responses. Results suggest that in cucumber the expanded LOX genes may play more diverse roles in life cycle and comprehensive data generated will be helpful in conducting functional genomic studies to understand their precise roles in cucumber fruit development and stress responses. Full article
(This article belongs to the Section Biochemistry)
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Article
Spectroscopic Parameter and Molecular Constant Investigations on Low-Lying States of BeF Radical
by Zun Lue Zhu, Qing Peng Song, Su Hua Kou, Jian Hua Lang and Jin Feng Sun
Int. J. Mol. Sci. 2012, 13(2), 2501-2514; https://doi.org/10.3390/ijms13022501 - 22 Feb 2012
Cited by 5 | Viewed by 5977
Abstract
The potential energy curves (PECs) of X2Σ+, A2Πr and B2Σ+ states of BeF radical have been investigated using the complete active space self-consistent-field (CASSCF) method, followed by the highly accurate valence internally contracted [...] Read more.
The potential energy curves (PECs) of X2Σ+, A2Πr and B2Σ+ states of BeF radical have been investigated using the complete active space self-consistent-field (CASSCF) method, followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI) approach at the correlation-consistent basis sets, cc-pV5Z for Be and aug-cc-pV6Z for F. Based on the PECs of X2Σ+, A2Πr and B2Σ+ states, the spectroscopic parameters (De, Re, ωe, ωeχe, αe and Be) have also been determined in the present work. With the PECs determined at the present level of theory, vibrational states have been predicted for each state when the rotational quantum number J equals zero (J = 0). The vibrational levels, inertial rotation and centrifugal distortion constants are determined for the three states, and the classical turning points are also calculated for the X2Σ+ state. Compared with the available experiments and other theories, it can be seen that the present spectroscopic parameter and molecular constant results are more fully in agreement with the experimental findings. Full article
(This article belongs to the Special Issue Advances in Molecular Electronic Structure Calculations)
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88 KiB  
Communication
Isolation and Characterization of New Microsatellite Markers for the Invasive Softshell Clam, Mya arenaria (L.) (Bivalvia: Myidae)
by Ana-Maria Krapal, Oana Paula Popa, Elena Iulia Iorgu, Marieta Costache and Luis Ovidiu Popa
Int. J. Mol. Sci. 2012, 13(2), 2515-2520; https://doi.org/10.3390/ijms13022515 - 22 Feb 2012
Cited by 4 | Viewed by 6073
Abstract
The invasive softshell clam (Mya arenaria Linnaeus, 1758) is native to the northwestern region of the Atlantic Ocean. This species has been introduced in the northeast Pacific and along the European coasts, due to intense naval transports and aquaculture, and it is [...] Read more.
The invasive softshell clam (Mya arenaria Linnaeus, 1758) is native to the northwestern region of the Atlantic Ocean. This species has been introduced in the northeast Pacific and along the European coasts, due to intense naval transports and aquaculture, and it is now present in all the European seas. In this paper we describe seven new microsatellite loci for Mya arenaria. The isolated loci are polymorphic with a number of alleles per locus between 6 and 14. The observed and expected heterozygosities ranged from 0.417 to 0.951, and from 0.643 to 0.895, with an average of 0.716 and 0.775, respectively. These microsatellite markers should be useful in analyzing this species’ genetic diversity, which could explain various processes of its invasion history. Full article
(This article belongs to the Section Biochemistry)
1040 KiB  
Article
Antiproliferative and Proapoptotic Activities of Methanolic Extracts from Ligustrum vulgare L. as an Individual Treatment and in Combination with Palladium Complex
by Milena G. Ćurčić, Milan S. Stanković, Emina M. Mrkalić, Zoran D. Matović, Dragić D. Banković, Danijela M. Cvetković, Dragana S. Đačić and Snežana D. Marković
Int. J. Mol. Sci. 2012, 13(2), 2521-2534; https://doi.org/10.3390/ijms13022521 - 22 Feb 2012
Cited by 53 | Viewed by 7390
Abstract
The aim of this study is to examine the growth inhibitory effects of methanolic leaf and fruit extracts of L. vulgare on HCT-116 cells over different time periods and their synergistic effect with a Pd(apox) complex. The antiproliferative activity of plant extracts alone [...] Read more.
The aim of this study is to examine the growth inhibitory effects of methanolic leaf and fruit extracts of L. vulgare on HCT-116 cells over different time periods and their synergistic effect with a Pd(apox) complex. The antiproliferative activity of plant extracts alone or in combination with the Pd(apox) complex was determined using MTT cell viability assay, where the IC50 value was used as a parameter of cytotoxicity. Results show that antiproliferative effects of L. vulgare extracts increase with extension of exposure time, with decreasing IC50 values, except for 72 h where the IC50 values for methanolic leaf extract were lower than for the fruit extract. The Pd(apox) complex alone had a weak antiproliferative effect, but combination with L. vulgare extracts caused stronger effects with lower IC50 values than with L. vulgare extracts alone. The type of cell death was explored by fluorescence microscopy using the acridin orange/ethidium bromide method. Treatments with plant extracts caused typical apoptotic morphological changes in HCT-116 cells and co-treatments with Pd(apox) complex caused higher levels of apoptotic cells than treatment with plant extracts alone. The results indicate that L. vulgare is a considerable source of natural bioactive substances with antiproliferative activity on HCT-116 cells and which have a substantial synergistic effect with the Pd(apox) complex. Full article
(This article belongs to the Section Biochemistry)
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Review

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204 KiB  
Review
Molecular Diagnostic and Pathogenesis of Hereditary Hemochromatosis
by Paulo C. J. L. Santos, Jose E. Krieger and Alexandre C. Pereira
Int. J. Mol. Sci. 2012, 13(2), 1497-1511; https://doi.org/10.3390/ijms13021497 - 01 Feb 2012
Cited by 67 | Viewed by 18559
Abstract
Hereditary hemochromatosis (HH) is an autosomal recessive disorder characterized by enhanced intestinal absorption of dietary iron. Without therapeutic intervention, iron overload leads to multiple organ damage such as liver cirrhosis, cardiomyopathy, diabetes, arthritis, hypogonadism and skin pigmentation. Most HH patients carry HFE mutant [...] Read more.
Hereditary hemochromatosis (HH) is an autosomal recessive disorder characterized by enhanced intestinal absorption of dietary iron. Without therapeutic intervention, iron overload leads to multiple organ damage such as liver cirrhosis, cardiomyopathy, diabetes, arthritis, hypogonadism and skin pigmentation. Most HH patients carry HFE mutant genotypes: homozygosity for p.Cys282Tyr or p.Cys282Tyr/p.His63Asp compound heterozygosity. In addition to HFE gene, mutations in the genes that encode hemojuvelin (HJV), hepcidin (HAMP), transferrin receptor 2 (TFR2) and ferroportin (SLC40A1) have been associated with regulation of iron homeostasis and development of HH. The aim of this review was to identify the main gene mutations involved in the pathogenesis of type 1, 2, 3 and 4 HH and their genetic testing indication. HFE testing for the two main mutations (p.Cys282Tyr and p.His63Asp) should be performed in all patients with primary iron overload and unexplained increased transferrin saturation and/or serum ferritin values. The evaluation of the HJV p.Gly320Val mutation must be the molecular test of choice in suspected patients with juvenile hemochromatosis with less than 30 years and cardiac or endocrine manifestations. In conclusion, HH is an example that genetic testing can, in addition to performing the differential diagnostic with secondary iron overload, lead to more adequate and faster treatment. Full article
(This article belongs to the Special Issue Advances in Molecular Diagnostics)
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Review
Dietary Fibers and Cardiometabolic Diseases
by Graziano Riccioni, Valeriana Sblendorio, Eugenio Gemello, Barbara Di Bello, Luca Scotti, Salvatore Cusenza and Nicolantonio D’Orazio
Int. J. Mol. Sci. 2012, 13(2), 1524-1540; https://doi.org/10.3390/ijms13021524 - 02 Feb 2012
Cited by 29 | Viewed by 7342
Abstract
The high prevalence of cardiovascular disease (CVD) is largely attributable to the contemporary lifestyle that is often sedentary and includes a diet high in saturated fats and sugars and low ingestion of polyunsaturated fatty acids (PUFAs), fruit, vegetables, and fiber. Experimental data from [...] Read more.
The high prevalence of cardiovascular disease (CVD) is largely attributable to the contemporary lifestyle that is often sedentary and includes a diet high in saturated fats and sugars and low ingestion of polyunsaturated fatty acids (PUFAs), fruit, vegetables, and fiber. Experimental data from both animals and humans suggest an association between increased dietary fiber (DF) intakes and improved plasma lipid profiles, including reduced low density lipoprotein cholesterol (LDL-C) concentrations. These observations underline that the intake of DF may protect against heart disease and stroke. Full article
(This article belongs to the Section Biochemistry)
144 KiB  
Review
Risks of Using Antifouling Biocides in Aquaculture
by Francisco Antonio Guardiola, Alberto Cuesta, José Meseguer and Maria Angeles Esteban
Int. J. Mol. Sci. 2012, 13(2), 1541-1560; https://doi.org/10.3390/ijms13021541 - 02 Feb 2012
Cited by 186 | Viewed by 13557
Abstract
Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and [...] Read more.
Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and antifoulant compounds (biocides) to eliminate the microorganisms in the aquaculture facilities. The use of biocides in the aquatic environment, however, has proved to be harmful as it has toxic effects on the marine environment. Organic booster biocides were recently introduced as alternatives to the organotin compounds found in antifouling products after restrictions were imposed on the use of tributyltin (TBT). The replacement products are generally based on copper metal oxides and organic biocides. The biocides that are most commonly used in antifouling paints include chlorothalonil, dichlofluanid, DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, Sea-nine 211®), Diuron, Irgarol 1051, TCMS pyridine (2,3,3,6-tetrachloro-4-methylsulfonyl pyridine), zinc pyrithione and Zineb. There are two types of risks associated with the use of biocides in aquaculture: (i) predators and humans may ingest the fish and shellfish that have accumulated in these contaminants and (ii) the development of antibiotic resistance in bacteria. This paper provides an overview of the effects of antifouling (AF) biocides on aquatic organisms. It also provides some insights into the effects and risks of these compounds on non-target organisms. Full article
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Review
Aggregating Data for Computational Toxicology Applications: The U.S. Environmental Protection Agency (EPA) Aggregated Computational Toxicology Resource (ACToR) System
by Richard S. Judson, Matthew T. Martin, Peter Egeghy, Sumit Gangwal, David M. Reif, Parth Kothiya, Maritja Wolf, Tommy Cathey, Thomas Transue, Doris Smith, James Vail, Alicia Frame, Shad Mosher, Elaine A. Cohen Hubal and Ann M. Richard
Int. J. Mol. Sci. 2012, 13(2), 1805-1831; https://doi.org/10.3390/ijms13021805 - 09 Feb 2012
Cited by 103 | Viewed by 12915
Abstract
Computational toxicology combines data from high-throughput test methods, chemical structure analyses and other biological domains (e.g., genes, proteins, cells, tissues) with the goals of predicting and understanding the underlying mechanistic causes of chemical toxicity and for predicting toxicity of new chemicals and products. [...] Read more.
Computational toxicology combines data from high-throughput test methods, chemical structure analyses and other biological domains (e.g., genes, proteins, cells, tissues) with the goals of predicting and understanding the underlying mechanistic causes of chemical toxicity and for predicting toxicity of new chemicals and products. A key feature of such approaches is their reliance on knowledge extracted from large collections of data and data sets in computable formats. The U.S. Environmental Protection Agency (EPA) has developed a large data resource called ACToR (Aggregated Computational Toxicology Resource) to support these data-intensive efforts. ACToR comprises four main repositories: core ACToR (chemical identifiers and structures, and summary data on hazard, exposure, use, and other domains), ToxRefDB (Toxicity Reference Database, a compilation of detailed in vivo toxicity data from guideline studies), ExpoCastDB (detailed human exposure data from observational studies of selected chemicals), and ToxCastDB (data from high-throughput screening programs, including links to underlying biological information related to genes and pathways). The EPA DSSTox (Distributed Structure-Searchable Toxicity) program provides expert-reviewed chemical structures and associated information for these and other high-interest public inventories. Overall, the ACToR system contains information on about 400,000 chemicals from 1100 different sources. The entire system is built using open source tools and is freely available to download. This review describes the organization of the data repository and provides selected examples of use cases. Full article
(This article belongs to the Section Molecular Toxicology)
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863 KiB  
Review
Yeast Mitochondrial Interactosome Model: Metabolon Membrane Proteins Complex Involved in the Channeling of ADP/ATP
by Benjamin Clémençon
Int. J. Mol. Sci. 2012, 13(2), 1858-1885; https://doi.org/10.3390/ijms13021858 - 10 Feb 2012
Cited by 11 | Viewed by 10645
Abstract
The existence of a mitochondrial interactosome (MI) has been currently well established in mammalian cells but the exact composition of this super-complex is not precisely known, and its organization seems to be different from that in yeast. One major difference is the absence [...] Read more.
The existence of a mitochondrial interactosome (MI) has been currently well established in mammalian cells but the exact composition of this super-complex is not precisely known, and its organization seems to be different from that in yeast. One major difference is the absence of mitochondrial creatine kinase (MtCK) in yeast, unlike that described in the organization model of MI, especially in cardiac, skeletal muscle and brain cells. The aim of this review is to provide a detailed description of different partner proteins involved in the synergistic ADP/ATP transport across the mitochondrial membranes in the yeast Saccharomyces cerevisiae and to propose a new mitochondrial interactosome model. The ADP/ATP (Aacp) and inorganic phosphate (PiC) carriers as well as the VDAC (or mitochondrial porin) catalyze the import and export of ADP, ATP and Pi across the mitochondrial membranes. Aacp and PiC, which appear to be associated with the ATP synthase, consist of two nanomotors (F0, F1) under specific conditions and form ATP synthasome. Identification and characterization of such a complex were described for the first time by Pedersen and co-workers in 2003. Full article
(This article belongs to the Special Issue Molecular System Bioenergetics 2011)
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677 KiB  
Review
The mTOR Signalling Pathway in Human Cancer
by Helena Pópulo, José Manuel Lopes and Paula Soares
Int. J. Mol. Sci. 2012, 13(2), 1886-1918; https://doi.org/10.3390/ijms13021886 - 10 Feb 2012
Cited by 648 | Viewed by 25375
Abstract
The conserved serine/threonine kinase mTOR (the mammalian target of rapamycin), a downstream effector of the PI3K/AKT pathway, forms two distinct multiprotein complexes: mTORC1 and mTORC2. mTORC1 is sensitive to rapamycin, activates S6K1 and 4EBP1, which are involved in mRNA translation. It is activated [...] Read more.
The conserved serine/threonine kinase mTOR (the mammalian target of rapamycin), a downstream effector of the PI3K/AKT pathway, forms two distinct multiprotein complexes: mTORC1 and mTORC2. mTORC1 is sensitive to rapamycin, activates S6K1 and 4EBP1, which are involved in mRNA translation. It is activated by diverse stimuli, such as growth factors, nutrients, energy and stress signals, and essential signalling pathways, such as PI3K, MAPK and AMPK, in order to control cell growth, proliferation and survival. mTORC2 is considered resistant to rapamycin and is generally insensitive to nutrients and energy signals. It activates PKC-α and AKT and regulates the actin cytoskeleton. Deregulation of multiple elements of the mTOR pathway (PI3K amplification/mutation, PTEN loss of function, AKT overexpression, and S6K1, 4EBP1 and eIF4E overexpression) has been reported in many types of cancers, particularly in melanoma, where alterations in major components of the mTOR pathway were reported to have significant effects on tumour progression. Therefore, mTOR is an appealing therapeutic target and mTOR inhibitors, including the rapamycin analogues deforolimus, everolimus and temsirolimus, are submitted to clinical trials for treating multiple cancers, alone or in combination with inhibitors of other pathways. Importantly, temsirolimus and everolimus were recently approved by the FDA for the treatment of renal cell carcinoma, PNET and giant cell astrocytoma. Small molecules that inhibit mTOR kinase activity and dual PI3K-mTOR inhibitors are also being developed. In this review, we aim to survey relevant research, the molecular mechanisms of signalling, including upstream activation and downstream effectors, and the role of mTOR in cancer, mainly in melanoma. Full article
(This article belongs to the Section Biochemistry)
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737 KiB  
Review
Tumor Heterogeneity: Mechanisms and Bases for a Reliable Application of Molecular Marker Design
by Salvador J. Diaz-Cano
Int. J. Mol. Sci. 2012, 13(2), 1951-2011; https://doi.org/10.3390/ijms13021951 - 13 Feb 2012
Cited by 118 | Viewed by 12969
Abstract
Tumor heterogeneity is a confusing finding in the assessment of neoplasms, potentially resulting in inaccurate diagnostic, prognostic and predictive tests. This tumor heterogeneity is not always a random and unpredictable phenomenon, whose knowledge helps designing better tests. The biologic reasons for this intratumoral [...] Read more.
Tumor heterogeneity is a confusing finding in the assessment of neoplasms, potentially resulting in inaccurate diagnostic, prognostic and predictive tests. This tumor heterogeneity is not always a random and unpredictable phenomenon, whose knowledge helps designing better tests. The biologic reasons for this intratumoral heterogeneity would then be important to understand both the natural history of neoplasms and the selection of test samples for reliable analysis. The main factors contributing to intratumoral heterogeneity inducing gene abnormalities or modifying its expression include: the gradient ischemic level within neoplasms, the action of tumor microenvironment (bidirectional interaction between tumor cells and stroma), mechanisms of intercellular transference of genetic information (exosomes), and differential mechanisms of sequence-independent modifications of genetic material and proteins. The intratumoral heterogeneity is at the origin of tumor progression and it is also the byproduct of the selection process during progression. Any analysis of heterogeneity mechanisms must be integrated within the process of segregation of genetic changes in tumor cells during the clonal expansion and progression of neoplasms. The evaluation of these mechanisms must also consider the redundancy and pleiotropism of molecular pathways, for which appropriate surrogate markers would support the presence or not of heterogeneous genetics and the main mechanisms responsible. This knowledge would constitute a solid scientific background for future therapeutic planning. Full article
(This article belongs to the Special Issue Advances in Molecular Pathology)
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Review
Effect of the Leaving Group and Solvent Combination on the LFER Reaction Constants
by Mirela Matić, Sandra Jurić, Bernard Denegri and Olga Kronja
Int. J. Mol. Sci. 2012, 13(2), 2012-2024; https://doi.org/10.3390/ijms13022012 - 13 Feb 2012
Cited by 13 | Viewed by 6626
Abstract
Fine effects that influence the variations of the reaction constants sf in LFER log k = sf(Nf + Ef) have been summarized here. Increasing solvent polarity in the series of binary mixtures increases the solvolysis rates [...] Read more.
Fine effects that influence the variations of the reaction constants sf in LFER log k = sf(Nf + Ef) have been summarized here. Increasing solvent polarity in the series of binary mixtures increases the solvolysis rates for the same factor for all benzhydryl derivatives in which the solvation of the leaving group moiety in the transition state is substantial, i.e., log k vs. Ef correlation lines are parallel (same sf). For the substrates in which the demand for solvation of the leaving groups moiety is reduced, (e.g., carbonates) sf parameters decrease as the fraction of the water in a given solvent/water mixture increases (log k vs. Ef plots converge), due to decreasing solvation of the electrofuge moiety toward bigger electrofugality. The abscissa of the intersection of the converging plots might indicate the critical electrofugality above which the solvolysis rates should not depend of the water fraction. Larger reaction constant sf indicate later transition state for structurally related substrates only, while sf parameters for structurally different substrates cannot be compared likely due to different intrinsic barriers. Inversion in relative abilities of leaving groups is possible if they have similar reactivities and are characterized with different reaction constants. Full article
(This article belongs to the Special Issue Correlation Analysis Applied to Solvolysis Reactions)
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357 KiB  
Review
Antioxidant-Induced Stress
by Cleva Villanueva and Robert D. Kross
Int. J. Mol. Sci. 2012, 13(2), 2091-2109; https://doi.org/10.3390/ijms13022091 - 16 Feb 2012
Cited by 113 | Viewed by 12217
Abstract
Antioxidants are among the most popular health-protecting products, sold worldwide without prescription. Indeed, there are many reports showing the benefits of antioxidants but only a few questioning the possible harmful effects of these “drugs”. The normal balance between antioxidants and free radicals in [...] Read more.
Antioxidants are among the most popular health-protecting products, sold worldwide without prescription. Indeed, there are many reports showing the benefits of antioxidants but only a few questioning the possible harmful effects of these “drugs”. The normal balance between antioxidants and free radicals in the body is offset when either of these forces prevails. The available evidence on the harmful effects of antioxidants is analyzed in this review. In summary, a hypothesis is presented that “antioxidant-induced stress” results when antioxidants overwhelm the body’s free radicals. Full article
(This article belongs to the Special Issue Bioactive Nanoparticles (special issue))
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334 KiB  
Review
Alpha7 Nicotinic Acetylcholine Receptor Is a Target in Pharmacology and Toxicology
by Miroslav Pohanka
Int. J. Mol. Sci. 2012, 13(2), 2219-2238; https://doi.org/10.3390/ijms13022219 - 17 Feb 2012
Cited by 151 | Viewed by 16868
Abstract
Alpha7 nicotinic acetylcholine receptor (α7 nAChR) is an important part of the cholinergic nerve system in the brain. Moreover, it is associated with a cholinergic anti-inflammatory pathway in the termination of the parasympathetic nervous system. Antagonists of α7 nAChR are a wide group [...] Read more.
Alpha7 nicotinic acetylcholine receptor (α7 nAChR) is an important part of the cholinergic nerve system in the brain. Moreover, it is associated with a cholinergic anti-inflammatory pathway in the termination of the parasympathetic nervous system. Antagonists of α7 nAChR are a wide group represented by conotoxin and bungarotoxin. Even Alzheimer’s disease drug memantine acting as an antagonist in its side pathway belongs in this group. Agonists of α7 nAChR are suitable for treatment of multiple cognitive dysfunctions such as Alzheimer’s disease or schizophrenia. Inflammation or even sepsis can be ameliorated by the agonistic acting compounds. Preparations RG3487, SEN34625/WYE-103914, SEN12333, ABT-107, Clozapine, GTS-21, CNI-1493, and AR-R17779 are representative examples of the novel compounds with affinity toward the α7 nAChR. Pharmacological, toxicological, and medicinal significance of α7 nAChR are discussed throughout this paper. Full article
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368 KiB  
Review
Epigenetic Disregulation in Oral Cancer
by Massimo Mascolo, Maria Siano, Gennaro Ilardi, Daniela Russo, Francesco Merolla, Gaetano De Rosa and Stefania Staibano
Int. J. Mol. Sci. 2012, 13(2), 2331-2353; https://doi.org/10.3390/ijms13022331 - 21 Feb 2012
Cited by 100 | Viewed by 10920
Abstract
Squamous cell carcinoma of the oral region (OSCC) is one of the most common and highly aggressive malignancies worldwide, despite the fact that significant results have been achieved during the last decades in its detection, prevention and treatment. Although many efforts have been [...] Read more.
Squamous cell carcinoma of the oral region (OSCC) is one of the most common and highly aggressive malignancies worldwide, despite the fact that significant results have been achieved during the last decades in its detection, prevention and treatment. Although many efforts have been made to define the molecular signatures that identify the clinical outcome of oral cancers, OSCC still lacks reliable prognostic molecular markers. Scientific evidence indicates that transition from normal epithelium to pre-malignancy, and finally to oral carcinoma, depends on the accumulation of genetic and epigenetic alterations in a multistep process. Unlike genetic alterations, epigenetic changes are heritable and potentially reversible. The most common examples of such changes are DNA methylation, histone modification, and small non-coding RNAs. Although several epigenetic changes have been currently linked to OSCC initiation and progression, they have been only partially characterized. Over the last decade, it has been demonstrated that especially aberrant DNA methylation plays a critical role in oral cancer. The major goal of the present paper is to review the recent literature about the epigenetic modifications contribution in early and later phases of OSCC malignant transformation; in particular we point out the current evidence of epigenetic marks as novel markers for early diagnosis and prognosis as well as potential therapeutic targets in oral cancer. Full article
(This article belongs to the Special Issue Advances in Molecular Pathology)
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320 KiB  
Review
Impaired Iron Status in Aging Research
by Jinze Xu, Zhenhua Jia, Mitchell D. Knutson and Christiaan Leeuwenburgh
Int. J. Mol. Sci. 2012, 13(2), 2368-2386; https://doi.org/10.3390/ijms13022368 - 22 Feb 2012
Cited by 71 | Viewed by 10350
Abstract
Aging is associated with disturbances in iron metabolism and storage. During the last decade, remarkable progress has been made toward understanding their cellular and molecular mechanisms in aging and age-associated diseases using both cultured cells and animal models. The field has moved beyond [...] Read more.
Aging is associated with disturbances in iron metabolism and storage. During the last decade, remarkable progress has been made toward understanding their cellular and molecular mechanisms in aging and age-associated diseases using both cultured cells and animal models. The field has moved beyond descriptive studies to potential intervention studies focusing on iron chelation and removal. However, some findings remain controversial and inconsistent. This review summarizes important features of iron dyshomeostasis in aging research with a particular emphasis on current knowledge of the mechanisms underlying age-associated disorders in rodent models. Full article
(This article belongs to the Special Issue Oxidative Stress and Mitochondria)
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Other

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25 KiB  
Retraction
Retraction: Zhong Ye; Darya O. Mishchuk; Natasha S. Stephens and Carolyn M. Slupsky. Dextran Sulfate Sodium Inhibits Alanine Synthesis in Caco-2 Cells. Int. J. Mol. Sci. 2011, 12, 2325-2335.
by Shu-Kun Lin
Int. J. Mol. Sci. 2012, 13(2), 1804; https://doi.org/10.3390/ijms13021804 - 09 Feb 2012
Cited by 1 | Viewed by 6132
Abstract
It has been brought to our attention by the corresponding author that the results presented this article [1] are in error due to the fact that the media supplement glutaMAX was used in place of L-glutamine for culture of the control cells, while [...] Read more.
It has been brought to our attention by the corresponding author that the results presented this article [1] are in error due to the fact that the media supplement glutaMAX was used in place of L-glutamine for culture of the control cells, while L-glutamine was used for culture of the treated cells. All authors have confirmed that the reported result could not be reproduced using the correct culture conditions. We would like to thank the authors for pointing out this error thereby upholding the ethics of scientific publication. The Editorial Team and Publisher have agreed with the authors that this manuscript should be retracted. We apologize for any inconvenience this may have caused. Full article
(This article belongs to the Special Issue Advances in Molecular Toxicology)
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