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Int. J. Mol. Sci., Volume 12, Issue 6 (June 2011) , Pages 3394-4179

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Open AccessArticle
TNF-α-Induced VEGF and MMP-9 Expression Promotes Hemorrhagic Transformation in Pituitary Adenomas
Int. J. Mol. Sci. 2011, 12(6), 4165-4179; https://doi.org/10.3390/ijms12064165 - 23 Jun 2011
Cited by 21 | Viewed by 4477
Abstract
Pituitary apoplexy is a clinical syndrome with unknown pathogenesis. Therefore, identifying the underlying mechanisms is of high clinical relevance. Tumor necrosis factor alpha (TNF-α) is a critical cytokine mediating various hemorrhagic events, but little is known about its involvement in pituitary apoplexy. Here [...] Read more.
Pituitary apoplexy is a clinical syndrome with unknown pathogenesis. Therefore, identifying the underlying mechanisms is of high clinical relevance. Tumor necrosis factor alpha (TNF-α) is a critical cytokine mediating various hemorrhagic events, but little is known about its involvement in pituitary apoplexy. Here we show that TNF-α may be an important regulator of hemorrhagic transformation in pituitary adenomas. In this study, sixty surgical specimens of hemorrhagic and non-hemorrhagic human pituitary adenomas were examined. Hemorrhagic pituitary adenomas displayed higher protein and mRNA levels of TNF-α, vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) compared with those of non-hemorrhagic tumors. Exposure of MMQ pituitary adenoma cells to TNF-α induced VEGF and MMP-9 expression in vitro. Additionally, TNF-α administration caused hemorrhagic transformation and enhanced VEGF and MMP-9 expression in MMQ pituitary adenoma cell xenografts in mice. Blockers of VEGF or MMP-9, either alone or in combination, attenuated but not abrogated TNF-α mediated hemorrhagic transformation in xenografts. This study suggests that TNF-α may play a role in the development of intratumoral hemorrhage in pituitary adenomas via up-regulation of VEGF and MMP-9. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Optimization of DNA Extraction for RAPD and ISSR Analysis of Arbutus unedo L. Leaves
Int. J. Mol. Sci. 2011, 12(6), 4156-4164; https://doi.org/10.3390/ijms12064156 - 22 Jun 2011
Cited by 14 | Viewed by 5105
Abstract
Genetic analysis of plants relies on high yields of pure DNA. For the strawberry tree (Arbutus unedo) this represents a great challenge since leaves can accumulate large amounts of polysaccharides, polyphenols and secondary metabolites, which co-purify with DNA. For this specie, [...] Read more.
Genetic analysis of plants relies on high yields of pure DNA. For the strawberry tree (Arbutus unedo) this represents a great challenge since leaves can accumulate large amounts of polysaccharides, polyphenols and secondary metabolites, which co-purify with DNA. For this specie, standard protocols do not produce efficient yields of high-quality amplifiable DNA. Here, we present for the first time an improved leaf-tissue protocol, based on the standard cetyl trimethyl ammonium bromide protocol, which yields large amounts of high-quality amplifiable DNA. Key steps in the optimized protocol are the addition of antioxidant compounds—namely polyvinyl pyrrolidone (PVP), 1,4-dithiothreitol (DTT) and 2-mercaptoethanol, in the extraction buffer; the increasing of CTAB (3%, w/v) and sodium chloride (2M) concentration; and an extraction with organic solvents (phenol and chloroform) with the incubation of samples on ice. Increasing the temperature for cell lyses to 70 °C also improved both DNA quality and yield. The yield of DNA extracted was 200.0 ± 78.0 µg/µL and the purity, evaluated by the ratio A260/A280, was 1.80 ± 0.021, indicative of minimal levels of contaminating metabolites. The quality of the DNA isolated was confirmed by random amplification polymorphism DNA and by inter-simple sequence repeat amplification, proving that the DNA can be amplified via PCR. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Modulation of rosR Expression and Exopolysaccharide Production in Rhizobium leguminosarum bv. trifolii by Phosphate and Clover Root Exudates
Int. J. Mol. Sci. 2011, 12(6), 4132-4155; https://doi.org/10.3390/ijms12064132 - 22 Jun 2011
Cited by 21 | Viewed by 4569
Abstract
The acidic exopolysaccharide (EPS) secreted in large amounts by the symbiotic nitrogen-fixing bacterium Rhizobium leguminosarum bv. trifolii is required for the establishment of an effective symbiosis with the host plant Trifolium spp. EPS biosynthesis in rhizobia is a very complex process regulated at [...] Read more.
The acidic exopolysaccharide (EPS) secreted in large amounts by the symbiotic nitrogen-fixing bacterium Rhizobium leguminosarum bv. trifolii is required for the establishment of an effective symbiosis with the host plant Trifolium spp. EPS biosynthesis in rhizobia is a very complex process regulated at both transcriptional and post-transcriptional levels and influenced by various nutritional and environmental conditions. The R. leguminosarum bv. trifolii rosR gene encodes a transcriptional regulator with a C2H2 type zinc-finger motif involved in positive regulation of EPS synthesis. In silico sequence analysis of the 450-bp long rosR upstream region revealed the presence of several inverted repeats (IR1 to IR6) and motifs with significant identity to consensus sequences recognized by PhoB and LysR-type proteins associated with phosphate- and flavonoid-dependent gene regulation in R. leguminosarum. Using a set of sequentially truncated rosR-lacZ transcriptional fusions, the role of the individual motifs and the effect of phosphate and clover root exudates on rosR expression were established. In addition, the significance of IR4 inverted repeats in the repression, and P2–10 hexamer in the activation of rosR transcription, respectively, was found. The expression of rosR increased in the presence of phosphate (0.1–20 mM) and clover root exudates (10 μM). PHO boxes and the LysR motif located upstream of the rosR translation start site were engaged in the regulation of rosR transcription. The synthesis of EPS and biofilm formation decreased at high phosphate concentrations, but increased in the presence of clover root exudates, indicating a complex regulation of these processes. Full article
(This article belongs to the Section Biochemistry)
Open AccessCommunication
Antioxidant Activities of Hot Water Extracts from Various Spices
Int. J. Mol. Sci. 2011, 12(6), 4120-4131; https://doi.org/10.3390/ijms12064120 - 21 Jun 2011
Cited by 68 | Viewed by 5436
Abstract
Recently, the natural spices and herbs such as rosemary, oregano, and caraway have been used for the processing of meat products. This study investigates the antioxidant activity of 13 spices commonly used in meat processing plants. The hot water extracts were then used [...] Read more.
Recently, the natural spices and herbs such as rosemary, oregano, and caraway have been used for the processing of meat products. This study investigates the antioxidant activity of 13 spices commonly used in meat processing plants. The hot water extracts were then used for evaluation of total phenolic content, total flavonoids content and antioxidant activities. Our results show that the hot water extract of oregano gave the highest extraction yield (41.33%) whereas mace (7.64%) gave the lowest. The DPPH radical scavenging ability of the spice extracts can be ranked against ascorbic acid in the order ascorbic acid > clove > thyme > rosemary > savory > oregano. The values for superoxide anion radical scavenging activities were in the order of marjoram > rosemary > oregano > cumin > savory > basil > thyme > fennel > coriander > ascorbic acid. When compared to ascorbic acid (48.72%), the hydroxyl radical scavenging activities of turmeric and mace were found to be higher (p < 0.001). Clove had the highest total phenolic content (108.28 μg catechin equivalent (CE)/g). The total flavonoid content of the spices varied from 324.08 μg quercetin equivalent (QE)/g for thyme to 3.38 μg QE/g for coriander. Our results indicate that hot water extract of several spices had a high antioxidant activity which is partly due to the phenolic and flavonoid compounds. This provides basic data, having implications for further development of processed food products. Full article
(This article belongs to the Section Biochemistry)
Open AccessTechnical Note
Novel Polymorphic Microsatellite Loci for the Korean Black Scraper (Thamnaconus modestus), and Their Application to the Genetic Characterization of Wild and Farmed Populations
Int. J. Mol. Sci. 2011, 12(6), 4104-4119; https://doi.org/10.3390/ijms12064104 - 20 Jun 2011
Cited by 6 | Viewed by 3781
Abstract
In this study, we developed 20 polymorphic microsatellite markers for the Korean black scraper, Thamnaconus modestus (Günther, 1877), Monacanthidae, and used them to compare allelic variation between wild and hatchery populations in Korea. All loci were readily amplified and demonstrated allelic variability, with [...] Read more.
In this study, we developed 20 polymorphic microsatellite markers for the Korean black scraper, Thamnaconus modestus (Günther, 1877), Monacanthidae, and used them to compare allelic variation between wild and hatchery populations in Korea. All loci were readily amplified and demonstrated allelic variability, with the number of alleles ranging from 5–35 in the wild population and 5–22 in the farmed population. The average observed and expected heterozygosities were estimated, respectively, as 0.74 and 0.80 in the hatchery samples and 0.78 and 0.81 in the wild ones. These results indicate lower genetic variability in the hatchery population than in the wild population and minor, but significant, genetic differentiation between the two populations (FST = 0.005, P < 0.01). Additionally, cross-amplification was tested in another monacanthid species, Stephanolepis cirrhifer; many loci were found that yielded useful information. The high degree of polymorphism exhibited by the 20 microsatellites will be useful in future aquaculture and population genetic studies for developing conservation and management plans. Full article
(This article belongs to the Special Issue Advances in Molecular Ecology)
Open AccessReview
Back to the Suture: The Distribution of Intraspecific Genetic Diversity in and Around Anatolia
Int. J. Mol. Sci. 2011, 12(6), 4080-4103; https://doi.org/10.3390/ijms12064080 - 20 Jun 2011
Cited by 73 | Viewed by 5048
Abstract
The effect of ice ages in speciation and diversification is well established in the literature. In Europe, the Iberian, the Italian and the Balkan peninsulas comprise the main glacial refugia, where the subsequent re-population of Europe started. Though not studied as extensively, Anatolia [...] Read more.
The effect of ice ages in speciation and diversification is well established in the literature. In Europe, the Iberian, the Italian and the Balkan peninsulas comprise the main glacial refugia, where the subsequent re-population of Europe started. Though not studied as extensively, Anatolia has also been hinted to be a potential glacial refugium for Europe, and with its proximity to the Caucasus and the Middle East at the same time, has potential to exhibit high levels of intraspecific diversity. The more ubiquitous use and cheaper availability of molecular methods globally now makes it possible to better understand molecular ecology and evolution of the fauna and flora in the genetically understudied regions of the world, such as Anatolia. In this review, the molecular genetic studies undertaken in Anatolia in the last decade, for 29 species of plants and animals, are examined to determine general phylogeographic patterns. In this regard, two major patterns are observed and defined, showing genetic breaks within Anatolia and between Anatolia and the Balkans. A third pattern is also outlined, which suggests Anatolia may be a center of diversity for the surrounding regions. The patterns observed are discussed in terms of their relevance to the location of suture zones, postglacial expansion scenarios, the effect of geographic barriers to gene flow and divergence time estimates, in order to better understand the effect of the geological history of Anatolia on the evolutionary history of the inhabitant species. In view of the current state of knowledge delineated in the review, future research directions are suggested. Full article
(This article belongs to the Special Issue Advances in Molecular Ecology)
Open AccessArticle
In vitro Antioxidant of a Water-Soluble Polysaccharide from Dendrobium fimhriatum Hook.var.oculatum Hook
Int. J. Mol. Sci. 2011, 12(6), 4068-4079; https://doi.org/10.3390/ijms12064068 - 17 Jun 2011
Cited by 21 | Viewed by 3536
Abstract
A water-soluble crude polysaccharide (DFHP) obtained from the aqueous extracts of the stem of Dendrobium fimhriatum Hook.var.oculatum Hook through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 209.3 kDa. Monosaccharide analysis revealed [...] Read more.
A water-soluble crude polysaccharide (DFHP) obtained from the aqueous extracts of the stem of Dendrobium fimhriatum Hook.var.oculatum Hook through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 209.3 kDa. Monosaccharide analysis revealed that DFHP was composed of mannose, glucose and galactose in a content ratio of 37.52%; 43.16%; 19.32%. The investigation of antioxidant activity in vitro showed that DFHP is a potential antioxidant. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Esculetin Ameliorates Carbon Tetrachloride-Mediated Hepatic Apoptosis in Rats
Int. J. Mol. Sci. 2011, 12(6), 4053-4067; https://doi.org/10.3390/ijms12064053 - 16 Jun 2011
Cited by 38 | Viewed by 4876
Abstract
Esculetin (ESC) is a coumarin that is present in several plants such as Fraxinus rhynchophylla and Artemisia capillaris. Our previous study found that FR ethanol extract (FREtOH) significantly ameliorated rats’ liver function. This study was intended to investigate the protective [...] Read more.
Esculetin (ESC) is a coumarin that is present in several plants such as Fraxinus rhynchophylla and Artemisia capillaris. Our previous study found that FR ethanol extract (FREtOH) significantly ameliorated rats’ liver function. This study was intended to investigate the protective mechanism of ESC in hepatic apoptosis in rats induced by carbon tetrachloride. Rat hepatic apoptosis was induced by oral administration of CCl4. All rats were administered orally with CCl4 (20%, 0.5 mL/rat) twice a week for 8 weeks. Rats in the ESC groups were treated daily with ESC, and silymarin group were treated daily with silymarin. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) as well as the activities of the anti-oxidative enzymes glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase in the liver were measured. In addition, expression of liver apoptosis proteins and anti-apoptotic proteins were detected. ESC (100, 500 mg/kg) significantly reduced the elevated activities of serum ALT and AST caused by CCl4 and significantly increased the activities of catalase, GPx and SOD. Furthermore, ESC (100, 500 mg/kg) significantly decreased the levels of the proapoptotic proteins (t-Bid, Bak and Bad) and significantly increased the levels of the anti-apoptotic proteins (Bcl-2 and Bcl-xL). ESC inhibited the release of cytochrome c from mitochondria. In addition, the levels of activated caspase-9 and activated caspase-3 were significantly decreased in rats treated with ESC than those in rats treated with CCl4 alone. ESC significantly reduced CCl4-induced hepatic apoptosis in rats. Full article
(This article belongs to the Section Biochemistry)
Open AccessReview
Systematic Approaches towards the Development of Host-Directed Antiviral Therapeutics
Int. J. Mol. Sci. 2011, 12(6), 4027-4052; https://doi.org/10.3390/ijms12064027 - 15 Jun 2011
Cited by 34 | Viewed by 6238
Abstract
Since the onset of antiviral therapy, viral resistance has compromised the clinical value of small-molecule drugs targeting pathogen components. As intracellular parasites, viruses complete their life cycle by hijacking a multitude of host-factors. Aiming at the latter rather than the pathogen directly, host-directed [...] Read more.
Since the onset of antiviral therapy, viral resistance has compromised the clinical value of small-molecule drugs targeting pathogen components. As intracellular parasites, viruses complete their life cycle by hijacking a multitude of host-factors. Aiming at the latter rather than the pathogen directly, host-directed antiviral therapy has emerged as a concept to counteract evolution of viral resistance and develop broad-spectrum drug classes. This approach is propelled by bioinformatics analysis of genome-wide screens that greatly enhance insights into the complex network of host-pathogen interactions and generate a shortlist of potential gene targets from a multitude of candidates, thus setting the stage for a new era of rational identification of drug targets for host-directed antiviral therapies. With particular emphasis on human immunodeficiency virus and influenza virus, two major human pathogens, we review screens employed to elucidate host-pathogen interactions and discuss the state of database ontology approaches applicable to defining a therapeutic endpoint. The value of this strategy for drug discovery is evaluated, and perspectives for bioinformatics-driven hit identification are outlined. Full article
(This article belongs to the Special Issue A Systematic Development Method for Rational Drug Design)
Open AccessArticle
Development of 30 Novel Polymorphic Expressed Sequence Tags (EST)-Derived Microsatellite Markers for the Miiuy Croaker, Miichthys miiuy
Int. J. Mol. Sci. 2011, 12(6), 4021-4026; https://doi.org/10.3390/ijms12064021 - 15 Jun 2011
Cited by 11 | Viewed by 3354
Abstract
Expressed sequence tags (ESTs) can be used to identify microsatellite markers. We developed 30 polymorphic microsatellite markers from 5053 ESTs of the Miichthys miiuy. Out of 123 EST derived microsatellites for which PCR primers were designed, 30 loci were polymorphic in 30 [...] Read more.
Expressed sequence tags (ESTs) can be used to identify microsatellite markers. We developed 30 polymorphic microsatellite markers from 5053 ESTs of the Miichthys miiuy. Out of 123 EST derived microsatellites for which PCR primers were designed, 30 loci were polymorphic in 30 individuals from a single natural population with 2–13 alleles per locus. The observed and expected heterozygosities were from 0.1024 to 0.7917 and from 0.2732 to 0.8845, respectively. Nine loci deviated from the Hardy-Weinberg equilibrium, and linkage disequilibrium was significant between 22 pairs of loci. These polymorphic microsatellite loci will be useful for genetic diversity analysis and molecule-assisted breeding for M. miiuy. Full article
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
Open AccessArticle
Synthesis of Cross-Linked Chitosan and Application to Adsorption and Speciation of Se (VI) and Se (IV) in Environmental Water Samples by Inductively Coupled Plasma Optical Emission Spectrometry
Int. J. Mol. Sci. 2011, 12(6), 4009-4020; https://doi.org/10.3390/ijms12064009 - 14 Jun 2011
Cited by 10 | Viewed by 4516
Abstract
A new type of cross-linked chitosan was synthesized with Diethylene Triamine (DCCTS). The adsorption of Se (VI) on DCCTS was studied. The effect factors on adsorption and the adsorption mechanism were considered. The results indicated that the DCCTS could concentrate and separate Se [...] Read more.
A new type of cross-linked chitosan was synthesized with Diethylene Triamine (DCCTS). The adsorption of Se (VI) on DCCTS was studied. The effect factors on adsorption and the adsorption mechanism were considered. The results indicated that the DCCTS could concentrate and separate Se (IV) at pH = 3.6; the maximum adsorption efficiency was 94%, the adsorption equilibrium time was 30 min; the maximum adsorption capacity was 42.7 mg/g; the adsorption fitted Langmuir equation. A novel method for speciation of Se (VI) and Se (IV) in environmental water samples has been developed using DCCTS as adsorbent and ICP–OES as determination means. The detection limit of this method was 12 ng/L, the relatively standard deviation was 4.5% and the recovery was 99%~104%. Full article
(This article belongs to the Section Materials Science)
Open AccessArticle
The Inhibitory Effect of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) on the Monophenolase and Diphenolase Activities of Mushroom Tyrosinase
Int. J. Mol. Sci. 2011, 12(6), 3998-4008; https://doi.org/10.3390/ijms12063998 - 14 Jun 2011
Cited by 7 | Viewed by 3073
Abstract
In the present work, we investigated the effect of non-steroidal anti-inflammatory drugs (NSAIDs) on the monophenolase and diphenolase activity of mushroom tyrosinase. The results showed that diflunisal and indomethacin inhibited both monophenolase and diphenolase activity. For monophenolase activity, the lag time was extended [...] Read more.
In the present work, we investigated the effect of non-steroidal anti-inflammatory drugs (NSAIDs) on the monophenolase and diphenolase activity of mushroom tyrosinase. The results showed that diflunisal and indomethacin inhibited both monophenolase and diphenolase activity. For monophenolase activity, the lag time was extended in the presence of diflunisal. In the presence of indomethacin, the lag time did not change. IC50 values of monophenolase activity were estimated to be 0.112 mM (diflunisal) and 1.78 mM (indomethacin). Kinetic studies of monophenolase activity revealed that both diflunisal and indomethacin were non-competitive inhibitors. For diphenolase activity, IC50 values were estimated to be 0.197 mM (diflunisal) and 0.509 mM (indomethacin). Diflunisal and indomethacin were also found to be non-competitive diphenolase inhibitors. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Metathesis of Fatty Acid Ester Derivatives in 1,1-Dialkyl and 1,2,3-Trialkyl Imidazolium Type Ionic Liquids
Int. J. Mol. Sci. 2011, 12(6), 3989-3997; https://doi.org/10.3390/ijms12063989 - 14 Jun 2011
Cited by 8 | Viewed by 4439
Abstract
The self-metathesis of methyl oleate and methyl ricinoleate was carried out in the presence of ruthenium alkylidene catalysts 1–4 in [bmim] and [bdmim][X] type ionic liquids (RTILs) (X = PF6, BF4 and NTf2 [...] Read more.
The self-metathesis of methyl oleate and methyl ricinoleate was carried out in the presence of ruthenium alkylidene catalysts 1–4 in [bmim] and [bdmim][X] type ionic liquids (RTILs) (X = PF6, BF4 and NTf2) using the gas chromatographic technique. Best catalytic performance was obtained in [bdmim][X] type ionic liquids when compared with [bmim][X] type ionic liquids. Catalyst recycling studies were also carried out in the room temperature ionic liquids (RTILs) with catalysts 1–4 in order to explore their possible industrial application. Full article
(This article belongs to the Section Physical Chemistry, Theoretical and Computational Chemistry)
Open AccessReview
Applications and Implications of Neutral versus Non-neutral Markers in Molecular Ecology
Int. J. Mol. Sci. 2011, 12(6), 3966-3988; https://doi.org/10.3390/ijms12063966 - 14 Jun 2011
Cited by 93 | Viewed by 5956
Abstract
The field of molecular ecology has expanded enormously in the past two decades, largely because of the growing ease with which neutral molecular genetic data can be obtained from virtually any taxonomic group. However, there is also a growing awareness that neutral molecular [...] Read more.
The field of molecular ecology has expanded enormously in the past two decades, largely because of the growing ease with which neutral molecular genetic data can be obtained from virtually any taxonomic group. However, there is also a growing awareness that neutral molecular data can provide only partial insight into parameters such as genetic diversity, local adaptation, evolutionary potential, effective population size, and taxonomic designations. Here we review some of the applications of neutral versus adaptive markers in molecular ecology, discuss some of the advantages that can be obtained by supplementing studies of molecular ecology with data from non-neutral molecular markers, and summarize new methods that are enabling researchers to generate data from genes that are under selection. Full article
(This article belongs to the Special Issue Advances in Molecular Ecology)
Open AccessArticle
A Novel Cold-Active Lipase from Candida albicans: Cloning, Expression and Characterization of the Recombinant Enzyme
Int. J. Mol. Sci. 2011, 12(6), 3950-3965; https://doi.org/10.3390/ijms12063950 - 14 Jun 2011
Cited by 27 | Viewed by 5572
Abstract
A novel lipase gene lip5 from the yeast Candida albicans was cloned and sequenced. Alignment of amino acid sequences revealed that 86–34% identity exists with lipases from other Candida species. The lipase and its mutants were expressed in the yeast Pichia pastoris, [...] Read more.
A novel lipase gene lip5 from the yeast Candida albicans was cloned and sequenced. Alignment of amino acid sequences revealed that 86–34% identity exists with lipases from other Candida species. The lipase and its mutants were expressed in the yeast Pichia pastoris, where alternative codon usage caused the mistranslation of 154-Ser and 293-Ser as leucine. 154-Ser to leucine resulted in loss of expression of Lip5, and 293-Ser to leucine caused a marked reduction in the lipase activity. Lip5-DM, which has double mutations that revert 154 and 293 to serine residues, showed good lipase activity, and was overexpressed and purified by (NH4)2SO4 precipitation and ion-exchange chromatography. The pure Lip5-DM was stable at low temperatures ranging from 15–35 °C and pH 5–9, with the optimal conditions being 15–25 °C and pH 5–6. The activation energy of recombinant lipase was 8.5 Kcal/mol between 5 and 25 °C, suggesting that Lip5-DM was a cold–active lipase. Its activity was found to increase in the presence of Zn2+, but it was strongly inhibited by Fe2+, Fe3+, Hg2+ and some surfactants. In addition, the Lip5-DM could not tolerate water-miscible organic solvents. Lip5-DM exhibited a preference for the short- and medium-chain length p-nitrophenyl (C4 and C8 acyl group) esters rather than the long chain length p-nitrophenyl esters (C12, C16 and C18 acyl group) with highest activity observed with the C8 derivatives. The recombinant enzyme displayed activity toward triacylglycerols, such as olive oil and safflower oil. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Extracts and Constituents of Rubus chingii with 1,1-Diphenyl-2-picrylhydrazyl (DPPH) Free Radical Scavenging Activity
Int. J. Mol. Sci. 2011, 12(6), 3941-3949; https://doi.org/10.3390/ijms12063941 - 14 Jun 2011
Cited by 21 | Viewed by 3471
Abstract
The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the fruits of Rubus chingii was studied in vitro. Ethanolic extract, ethyl acetate and n-butanol fractions from dried R. chingii fruits revealed strong DPPH free radical scavenging activity with IC50 values of [...] Read more.
The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the fruits of Rubus chingii was studied in vitro. Ethanolic extract, ethyl acetate and n-butanol fractions from dried R. chingii fruits revealed strong DPPH free radical scavenging activity with IC50 values of 17.9, 3.4 and 4.0 µg/mL, respectively. The ethyl acetate and n-butanol fractions were further purified by a combination of silica gel chromatography, Lobar RP-8 chromatography, and high-pressure liquid chromatography (HPLC). Nine compounds were isolated, where methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (2), vanillic acid (5), kaempferol (7), and tiliroside (9) showed stronger DPPH free radical scavenging activity than that of ascorbic acid (131.8 µM) with IC50 values of 45.2, 34.9, 78.5, and 13.7 µM, respectively. In addition, rubusine (1) is a new compound discovered in the present study and methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (2), methyl dioxindole-3-acetate (3), and 2-oxo-1,2-dihydroquinoline-4-carboxylic acid (4) were isolated from the fruits for the first time. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Oral HPV Infection and Sexuality: A Cross-Sectional Study in Women
Int. J. Mol. Sci. 2011, 12(6), 3928-3940; https://doi.org/10.3390/ijms12063928 - 10 Jun 2011
Cited by 14 | Viewed by 5922
Abstract
Human Papillomavirus (HPV) is the main risk factor for cervical cancers and is associated with close to 36% of oropharyngeal cancers. There is increasing evidence that oral HPV transmission is related to sexual behavior but to our knowledge studies that involve women who [...] Read more.
Human Papillomavirus (HPV) is the main risk factor for cervical cancers and is associated with close to 36% of oropharyngeal cancers. There is increasing evidence that oral HPV transmission is related to sexual behavior but to our knowledge studies that involve women who have sex with women have not been performed. We examined the prevalence of oral HPV according to sexual behavior among a population-based sample of 118 women and have made some inferences of possible predictors of oral HPV infection. Women were categorized as heterosexual (history of vaginal sex and/or oral sex with males only, n = 75), bisexual (history of vaginal sex and oral sex with females, n = 32) and other (no history of vaginal sex but oral sex with females [homosexuals], virgins and women with incomplete sexual exposure data, n = 11) The prevalence of oral HPV infection was 12/118 (10.2%) for the overall study population and was not significantly different between heterosexual and bisexual women (10.7% (8/75) vs. 12.5% (4/32), p = 0.784). There was no oral HPV detected among homosexual women, virgins or among women where sexual exposure was unknown. Never smokers were more likely to be oral HPV+ compared to former smokers (Adjusted Odds Ratio (Adj OR) = 0.1, 95% CI, 0.0–1.1) and there was no difference in risk between never smokers and current smokers (Adj OR = 0.7, 95% CI, 0.1–4.6). Twenty-five percent (3/12) of oral HPV+ women had a history of HPV and/or genital warts compared to 9% (10/106) of oral HPV-women (p = 0.104). For the women with a history of vaginal sex (n = 110), oral HPV status was statistically significantly different according to oral sex exposure (p = 0.039). A higher proportion of oral HPV-positive women reported that they had no history of oral sex exposure compared to oral HPV-negative women (4/12, 33% vs. 7/98, 8%). The prevalence of cervical HPV infection did not vary between heterosexuals and bisexuals (35.7% (25/70) vs. 35.5% (11/31), p-value 0.411) and for all other women the cervical HPV prevalence was significantly lower (11.1%, 1/9). Our study suggests that smoking and sexual behavior involving males rather than female partners may be possible predictors of oral HPV infection in women. Further studies with larger sample size are needed to confirm these findings. Full article
(This article belongs to the Section Biochemistry)
Open AccessReview
Inorganic-Organic Hybrid Nanomaterials for Therapeutic and Diagnostic Imaging Applications
Int. J. Mol. Sci. 2011, 12(6), 3888-3927; https://doi.org/10.3390/ijms12063888 - 10 Jun 2011
Cited by 46 | Viewed by 6367
Abstract
Nanotechnology offers outstanding potential for future biomedical applications. In particular, due to their unique characteristics, hybrid nanomaterials have recently been investigated as promising platforms for imaging and therapeutic applications. This class of nanoparticles can not only retain valuable features of both inorganic and [...] Read more.
Nanotechnology offers outstanding potential for future biomedical applications. In particular, due to their unique characteristics, hybrid nanomaterials have recently been investigated as promising platforms for imaging and therapeutic applications. This class of nanoparticles can not only retain valuable features of both inorganic and organic moieties, but also provides the ability to systematically modify the properties of the hybrid material through the combination of functional elements. Moreover, the conjugation of targeting moieties on the surface of these nanomaterials gives them specific targeted imaging and therapeutic properties. In this review, we summarize the recent reports in the synthesis of hybrid nanomaterials and their applications in biomedical areas. Their applications as imaging and therapeutic agents in vivo will be highlighted. Full article
(This article belongs to the Special Issue Bioactive Nanoparticles (special issue))
Open AccessArticle
Butin (7,3′,4′-Trihydroxydihydroflavone) Reduces Oxidative Stress-Induced Cell Death via Inhibition of the Mitochondria-Dependent Apoptotic Pathway
Int. J. Mol. Sci. 2011, 12(6), 3871-3887; https://doi.org/10.3390/ijms12063871 - 10 Jun 2011
Cited by 7 | Viewed by 4646
Abstract
Recently, we demonstrated that butin (7,3′,4′-trihydroxydihydroflavone) protected cells against hydrogen peroxide (H2O2)-induced apoptosis by: (1) scavenging reactive oxygen species (ROS), activating antioxidant enzymes such superoxide dismutase and catalase; (2) decreasing oxidative stress-induced 8-hydroxy-2'-deoxyguanosine levels via activation of oxoguanine glycosylase [...] Read more.
Recently, we demonstrated that butin (7,3′,4′-trihydroxydihydroflavone) protected cells against hydrogen peroxide (H2O2)-induced apoptosis by: (1) scavenging reactive oxygen species (ROS), activating antioxidant enzymes such superoxide dismutase and catalase; (2) decreasing oxidative stress-induced 8-hydroxy-2'-deoxyguanosine levels via activation of oxoguanine glycosylase 1, and (3), reducing oxidative stress-induced mitochondrial dysfunction. The objective of this study was to determine the cytoprotective effects of butin on oxidative stress-induced mitochondria-dependent apoptosis, and possible mechanisms involved. Butin significantly reduced H2O2-induced loss of mitochondrial membrane potential as determined by confocal image analysis and flow cytometry, alterations in Bcl-2 family proteins such as decrease in Bcl-2 expression and increase in Bax and phospho Bcl-2 expression, release of cytochrome c from mitochondria into the cytosol and activation of caspases 9 and 3. Furthermore, the anti-apoptotic effect of butin was exerted via inhibition of mitogen-activated protein kinase kinase-4, c-Jun NH2-terminal kinase (JNK) and activator protein-1 cascades induced by H2O2 treatment. Finally, butin exhibited protective effects against H2O2-induced apoptosis, as demonstrated by decreased apoptotic bodies, sub-G1 hypodiploid cells and DNA fragmentation. Taken together, the protective effects of butin against H2O2-induced apoptosis were exerted via blockade of membrane potential depolarization, inhibition of the JNK pathway and mitochondria-involved caspase-dependent apoptotic pathway Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Structural Characterization of Poly-L-lactic Acid (PLLA) and Poly(glycolic acid)(PGA) Oligomers
Int. J. Mol. Sci. 2011, 12(6), 3857-3870; https://doi.org/10.3390/ijms12063857 - 10 Jun 2011
Cited by 7 | Viewed by 5412
Abstract
Structural characterization of poly-L-lactic acid (PLLA) and poly(glycolic acid) (PGA) oligomers containing three units was carried out with an atomistic approach. Oligomer structures were first optimized through quantum chemical calculations, using density functional theory (DFT); rotational barriers concerning dihedral angles along the chain [...] Read more.
Structural characterization of poly-L-lactic acid (PLLA) and poly(glycolic acid) (PGA) oligomers containing three units was carried out with an atomistic approach. Oligomer structures were first optimized through quantum chemical calculations, using density functional theory (DFT); rotational barriers concerning dihedral angles along the chain were then investigated. Diffusion coefficients of L-lactic acid and glycolic acid in pure water were estimated through molecular dynamic (MD) simulations. Monomer structures were obtained with quantum chemical computation in implicit water using DFT method; atomic charges were fitted with Restrained Electrostatic Potentials (RESP) formalism, starting from electrostatic potentials calculated with quantum chemistry. MD simulations were carried out in explicit water, in order to take into account solvent presence Full article
(This article belongs to the Special Issue Biodegradability of Materials in Biomedical Applications 2011)
Open AccessArticle
Protective Role of α2HS-Glycoprotein in HBV-Associated Liver Failure
Int. J. Mol. Sci. 2011, 12(6), 3846-3856; https://doi.org/10.3390/ijms12063846 - 10 Jun 2011
Cited by 6 | Viewed by 4544
Abstract
n this study, levels of plasma α2-Heremans-Schmid glycoprotein, serum tumor necrosis factor-α, serum liver function parameters and short-term mortality were measured in 100 hepatitis B patients. Release of interleukin-6 and tumor necrosis factor-α from the lipopolysaccharide-stimulated peripheral blood mononuclear cells in the presence/absence [...] Read more.
n this study, levels of plasma α2-Heremans-Schmid glycoprotein, serum tumor necrosis factor-α, serum liver function parameters and short-term mortality were measured in 100 hepatitis B patients. Release of interleukin-6 and tumor necrosis factor-α from the lipopolysaccharide-stimulated peripheral blood mononuclear cells in the presence/absence of spermine and α2-Heremans-Schmid glycoprotein were analyzed by enzyme-linked immunosorbent assay to determine the significance and potential mechanism of α2-Heremans-Schmid glycoprotein in hepatitis B virus-associated liver damage. Results showed that serum α2-Heremans-Schmid glycoprotein levels in acute-on-chronic liver failure patients were significantly lower than that in chronic hepatitis B patients or healthy controls (p < 0.05). A negative dependence between serum human α2-Heremans-Schmid glycoprotein and tumor necrosis factor-α levels was observed. Interleukin-6 and tumor necrosis factor-α levels in the lipopolysaccharide-induced peripheral blood mononuclear cell supernates were significantly reduced by spermine and/or α2-Heremans-Schmid glycoprotein. The latter two proteins jointly inhibited cytokine release. These observations suggest that plasma α2-Heremans-Schmid glycoprotein is an independent marker of liver damage and a prognostic indicator of hepatitis B virus chronicity. It may reduce liver inflammation by partially inhibiting release of inflammatory factors from activated peripheral blood mononuclear cells. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Proliferation-Attenuating and Apoptosis-Inducing Effects of Tryptanthrin on Human Chronic Myeloid Leukemia K562 Cell Line in Vitro
Int. J. Mol. Sci. 2011, 12(6), 3831-3845; https://doi.org/10.3390/ijms12063831 - 10 Jun 2011
Cited by 25 | Viewed by 4609
Abstract
Tryptanthrin, a kind of indole quinazoline alkaloid, has been shown to exhibit anti-microbial, anti-inflammation and anti-tumor effects both in vivo and in vitro. However, its biological activity on human chronic myeloid leukemia cell line K562 is not fully understood. In the present [...] Read more.
Tryptanthrin, a kind of indole quinazoline alkaloid, has been shown to exhibit anti-microbial, anti-inflammation and anti-tumor effects both in vivo and in vitro. However, its biological activity on human chronic myeloid leukemia cell line K562 is not fully understood. In the present study, we investigated the proliferation-attenuating and apoptosis-inducing effects of tryptanthrin on leukemia K562 cells in vitro and explored the underlying mechanisms. The results showed that tryptanthrin could significantly inhibit K562 cells proliferation in a time- and dose-dependent manner as evidenced by MTT assay and flow cytometry analysis. We also observed pyknosis, chromatin margination and the formation of apoptotic bodies in the presence of tryptanthrin under the electron microscope. Nuclei fragmentation and condensation by Hoechst 33258 staining were detected as well. The amount of apoptotic cells significantly increased whereas the mitochondrial membrane potential decreased dramatically after tryptanthrin exposure. K562 cells in the tryptanthrin treated group exhibited an increase in cytosol cyt-c, Bax and activated caspase-3 expression while a decrease in Bcl-2, mito cyt-c and pro-caspase-3 contents. However, the changes of pro-caspase-3 and activated caspase-3 could be abolished by a pan-caspase inhibitor ZVAD-FMK. These results suggest that tryptanthrin has proliferation-attenuating and apoptosis-inducing effects on K562 cells. The underlying mechanism is probably attributed to the reduction in mitochondria membrane potential, the release of mito cyt-c and pro-caspase-3 activation. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Synthesis of Brushite Particles in Reverse Microemulsions of the Biosurfactant Surfactin
Int. J. Mol. Sci. 2011, 12(6), 3821-3830; https://doi.org/10.3390/ijms12063821 - 09 Jun 2011
Cited by 25 | Viewed by 5932
Abstract
In this study the “green chemistry” use of the biosurfactant surfactin for the synthesis of calcium phosphate using the reverse microemulsion technique was demonstrated. Calcium phosphates are bioactive materials that are a major constituent of human teeth and bone tissue. A reverse microemulsion [...] Read more.
In this study the “green chemistry” use of the biosurfactant surfactin for the synthesis of calcium phosphate using the reverse microemulsion technique was demonstrated. Calcium phosphates are bioactive materials that are a major constituent of human teeth and bone tissue. A reverse microemulsion technique with surfactin was used to produce nanocrystalline brushite particles. Structural diversity (analyzed by SEM and TEM) resulted from different water to surfactin ratios (W/S; 250, 500, 1000 and 40,000). The particle sizes were found to be in the 16–200 nm range. Morphological variety was observed in the as-synthesized microemulsions, which consisted of nanospheres (~16 nm in diameter) and needle-like (8–14 nm in diameter and 80–100 nm in length) noncalcinated particles. However, the calcinated products included nanospheres (50–200 nm in diameter), oval (~300 nm in diameter) and nanorod (200–400 nm in length) particles. FTIR and XRD analysis confirmed the formation of brushite nanoparticles in the as-synthesized products, while calcium pyrophosphate was produced after calcination. These results indicate that the reverse microemulsion technique using surfactin is a green process suitable for the synthesis of nanoparticles. Full article
(This article belongs to the Section Materials Science)
Open AccessArticle
Screen-Printed Carbon Electrodes Modified with Cobalt Phthalocyanine for Selective Sulfur Detection in Cosmetic Products
Int. J. Mol. Sci. 2011, 12(6), 3810-3820; https://doi.org/10.3390/ijms12063810 - 09 Jun 2011
Cited by 9 | Viewed by 4837
Abstract
Cobalt phthalocyanine (CoPc) films were deposited on the surface of a screen-printed carbon electrode using a simple drop coating method. The cyclic voltammogram of the resulting CoPc modified screen-printed electrode (CoPc/SPE) prepared under optimum conditions shows a well-behaved redox couple due to the [...] Read more.
Cobalt phthalocyanine (CoPc) films were deposited on the surface of a screen-printed carbon electrode using a simple drop coating method. The cyclic voltammogram of the resulting CoPc modified screen-printed electrode (CoPc/SPE) prepared under optimum conditions shows a well-behaved redox couple due to the (CoI/CoII) system. The CoPc/SPE surface demonstrates excellent electrochemical activity towards the oxidation of sulfur in a 0.01 mol·L−1 NaOH. A linear calibration curve with the detection limit (DL, S/N = 3) of 0.325 mg·L−1 was achieved by CoPc/SPE coupled with flow injection analysis of the sulfur concentration ranging from 4 to 1120 mg·L−1. The precision of the system response was evaluated (3.60% and 3.52% RSD for 12 repeated injections), in the range of 64 and 480 mg·L−1 sulfur. The applicability of the method was successfully demonstrated in a real sample analysis of sulfur in anti-acne creams, and good recovery was obtained. The CoPc/SPE displayed several advantages in sulfur determination including easy fabrication, high stability, and low cost. Full article
(This article belongs to the Section Materials Science)
Open AccessArticle
Molecular Characterization and Expression Pattern of Tripartite Motif Protein 39 in Gallus gallus with a Complete PRY/SPRY Domain
Int. J. Mol. Sci. 2011, 12(6), 3797-3809; https://doi.org/10.3390/ijms12063797 - 09 Jun 2011
Cited by 2 | Viewed by 3369
Abstract
Members of tripartite motif (TRIM) proteins in mammals play important roles in multiple cellular processes in the immune system. In the present study we have obtained the chicken TRIM39 with the insertion of a base A at position 1006 bp, compared to the [...] Read more.
Members of tripartite motif (TRIM) proteins in mammals play important roles in multiple cellular processes in the immune system. In the present study we have obtained the chicken TRIM39 with the insertion of a base A at position 1006 bp, compared to the sequence in the NCBI database (Accession No: NM 001006196), which made TRIM39 fulfill the TRIM rule of domain composition with both PRY, and SPRY domains. The open reading frame consisted of 1392 bp encoding 463 amino acid residues. The amino acid sequences of TRIM39 protein in mammals were highly similar (from 91.48% to 99.61%), while chicken TRIM39 had relatively low homology with mammals (from 29.2% to 39.59%). Real time RT-PCR indicated that the mRNA expression level of TRIM39 was the highest in spleen, with a lower expression in liver, brain, and lung, suggesting it might be an important protein participating in the immune system. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Microwave Accelerated Transglycosylation of Rutin by Cyclodextrin Glucanotransferase from Bacillus sp. SK13.002
Int. J. Mol. Sci. 2011, 12(6), 3786-3796; https://doi.org/10.3390/ijms12063786 - 09 Jun 2011
Cited by 12 | Viewed by 5236
Abstract
Rutin was subjected to intermolecular transglycosylation assisted with microwave irradiation using cyclodextrin glucanotransferase (CGTase) produced from Bacillus sp. SK13.002. Compared with the conventional enzymatic method for rutin transglycosylation (without microwave irradiation), microwave-assisted reaction (MAR) was much faster and thus more efficient. While the [...] Read more.
Rutin was subjected to intermolecular transglycosylation assisted with microwave irradiation using cyclodextrin glucanotransferase (CGTase) produced from Bacillus sp. SK13.002. Compared with the conventional enzymatic method for rutin transglycosylation (without microwave irradiation), microwave-assisted reaction (MAR) was much faster and thus more efficient. While the conventional reaction took dozens of hours to reach the highest conversion rate of rutin and yield of transglycosylated rutin, MAR of rutin transglycosylation completed within only 6 min providing almost the same conversion rate of rutin and yield of products consisting of mono-, di-, tri-, tetra-, penta-glucosylated rutins. The optimum transglycosylation conditions for microwave irradiation were 40 °C and 60 W with the reaction system consisting mainly of the mixture of 0.3 g rutin (0.49 mmol) pre-dissolved in 15 mL methanol, 1.8 g maltodextrin in 15 mL of 0.2 M sodium acetate buffer (pH 5.5) and CGTase (900 U). Results from this study indicated that MAR could be a potentially useful and economical technique for a faster and more efficient transglycosylation of rutin. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Differences in Soil Properties and Bacterial Communities between the Rhizosphere and Bulk Soil and among Different Production Areas of the Medicinal Plant Fritillaria thunbergii
Int. J. Mol. Sci. 2011, 12(6), 3770-3785; https://doi.org/10.3390/ijms12063770 - 09 Jun 2011
Cited by 21 | Viewed by 5905
Abstract
To explore rhizosphere effects, geographical differences and their effects on the bacterial community associated with the geoherb Fritillaria thunbergii, some physicochemical properties of soil samples (3 sampling sites × 2 habitats (rhizosphere and bulk soil)) were measured and the soil bacterial community [...] Read more.
To explore rhizosphere effects, geographical differences and their effects on the bacterial community associated with the geoherb Fritillaria thunbergii, some physicochemical properties of soil samples (3 sampling sites × 2 habitats (rhizosphere and bulk soil)) were measured and the soil bacterial community detected by PCR-denaturing gradient gel electrophoresis (DGGE). Among the three regions, soil pH varied between 4.48 and 7.73 indicating that F. thunbergii could grow both in acid and slightly alkaline soil. As the authentic Dao-di producing area, Ningbo showed the highest soil quality with the highest content of organic matter (OM) (2.46%), phosphatase (268 mg kg−1 24 h−1) and urease activity (1481 mg kg−1 24 h−1). In comparison with the bulk soil, pH, organic carbon content, and phosphatase and urease activities were all lower in the rhizosphere, suggesting that the roots may secrete some unique metabolites in root exudates. Statistical analyses showed that soil properties of Ningbo and Panan in Zhejiang province were more similar to each other than those in Nantong in Jiangsu province. In addition, PCR-DGGE analysis showed that main bacterial population identified in F. thunbergii was proteobacteria (18 bands, 55%), acidobacteria (4, 12%), actinobacteria (4, 12%) and bacterioidetes (6, 18%). Overall, soil properties and microbial communities varied not only between the rhizosphere and bulk soil but also among the three regions. We suggest that the plant, together with the soil properties, cooperatively shape the structure of the rhizosphere bacteria, and that the soil properties have a close relationship with the geoherbalism of F. thunbergii. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Effects of Onion (Allium cepa L.) Extract Administration on Intestinal α-Glucosidases Activities and Spikes in Postprandial Blood Glucose Levels in SD Rats Model
Int. J. Mol. Sci. 2011, 12(6), 3757-3769; https://doi.org/10.3390/ijms12063757 - 08 Jun 2011
Cited by 49 | Viewed by 5191
Abstract
Diets high in calories and sweetened foods with disaccharides frequently lead to exaggerated postprandial spikes in blood glucose. This state induces immediate oxidant stress and free radicals which trigger oxidative stress-linked diabetic complications. One of the therapeutic approaches for decreasing postprandial hyperglycemia is [...] Read more.
Diets high in calories and sweetened foods with disaccharides frequently lead to exaggerated postprandial spikes in blood glucose. This state induces immediate oxidant stress and free radicals which trigger oxidative stress-linked diabetic complications. One of the therapeutic approaches for decreasing postprandial hyperglycemia is to retard absorption of glucose by the inhibition of carbohydrate hydrolyzing enzymes,α-amylase and α-glucosidases, in the digestive organs. Therefore, the inhibitory activity of Korean onion (Allium cepa L.) extract against rat intestinal α-glucosidases, such as sucrase, maltase, and porcine pancreatic α-amylase were investigated in vitro and in vivo. The content of quercetin in ethyl alcohol extract of onion skin (EOS) was 6.04 g/100 g dried weight of onion skin. The in vitro half-maximal inhibitory concentrations (IC50) of EOS and quercetin, a major phenolic in onion, on rat intestinal sucrase were 0.40 and 0.11 mg/mL, respectively. The postprandial blood glucose lowering effects of EOS and quercetin were compared to a known type 2 diabetes drug (Acarbose), a strong α-glucosidase inhibitor in the Sprague-Dawley (SD) rat model. In rats fed on sucrose, EOS significantly reduced the blood glucose spike after sucrose loading. The area under the blood glucose-time curve (AUClast) in EOS-treated SD rats (0.5 g-EOS/kg) was significantly lower than in untreated SD rats (259.6 ± 5.1 vs. 283.1 ± 19.2 h·mg/dL). The AUClast in quercetin-treated SD rats (0.5 g-quercetin/kg) was similar to in EOS-treated group (256.1 ± 3.2 vs. 259.6 ± 5.1 h·mg/dL). Results from this study indicates that although quercetin does have blood glucose lowering potential via α-glucosidase inhibition, there are other bioactive compounds present in onion skin. Furthermore, the effects of two weeks administration of EOS in a high carbohydrate-dietary mixture (Pico 5053) on sucrase and maltase activities in intestine were evaluated in SD rat model. Compared to the upper and middle parts of intestine, the activities of sucrase in the lower parts of intestine remained significantly higher after two weeks of EOS treatment. These results indicate that EOS may improve exaggerated postprandial spikes in blood glucose and glucose homeostasis since it inhibits intestinal sucrase and thus delays carbohydrate absorption, although clinical trials are needed. Full article
(This article belongs to the Section Biochemistry)
Open AccessArticle
Sulfotyrosine Recognition as Marker for Druggable Sites in the Extracellular Space
Int. J. Mol. Sci. 2011, 12(6), 3740-3756; https://doi.org/10.3390/ijms12063740 - 08 Jun 2011
Cited by 11 | Viewed by 4442
Abstract
Chemokine signaling is a well-known agent of autoimmune disease, HIV infection, and cancer. Drug discovery efforts for these signaling molecules have focused on developing inhibitors targeting their associated G protein-coupled receptors. Recently, we used a structure-based approach directed at the sulfotyrosine-binding pocket of [...] Read more.
Chemokine signaling is a well-known agent of autoimmune disease, HIV infection, and cancer. Drug discovery efforts for these signaling molecules have focused on developing inhibitors targeting their associated G protein-coupled receptors. Recently, we used a structure-based approach directed at the sulfotyrosine-binding pocket of the chemokine CXCL12, and thereby demonstrated that small molecule inhibitors acting upon the chemokine ligand form an alternative therapeutic avenue. Although the 50 members of the chemokine family share varying degrees of sequence homology (some as little as 20%), all members retain the canonical chemokine fold. Here we show that an equivalent sulfotyrosine-binding pocket appears to be conserved across the chemokine superfamily. We monitored sulfotyrosine binding to four representative chemokines by NMR. The results suggest that most chemokines harbor a sulfotyrosine recognition site analogous to the cleft on CXCL12 that binds sulfotyrosine 21 of the receptor CXCR4. Rational drug discovery efforts targeting these sites may be useful in the development of specific as well as broad-spectrum chemokine inhibitors. Full article
(This article belongs to the Special Issue A Systematic Development Method for Rational Drug Design)
Open AccessReview
Recent Advances in Plant Early Signaling in Response to Herbivory
Int. J. Mol. Sci. 2011, 12(6), 3723-3739; https://doi.org/10.3390/ijms12063723 - 07 Jun 2011
Cited by 77 | Viewed by 6035
Abstract
Plants are frequently attacked by herbivores and pathogens and therefore have acquired constitutive and induced defenses during the course of their evolution. Here we review recent progress in the study of the early signal transduction pathways in host plants in response to herbivory. [...] Read more.
Plants are frequently attacked by herbivores and pathogens and therefore have acquired constitutive and induced defenses during the course of their evolution. Here we review recent progress in the study of the early signal transduction pathways in host plants in response to herbivory. The sophisticated signaling network for plant defense responses is elicited and driven by both herbivore-induced factors (e.g., elicitors, effectors, and wounding) and plant signaling (e.g., phytohormone and plant volatiles) in response to arthropod factors. We describe significant findings, illuminating the scenario by providing broad insights into plant signaling involved in several arthropod-host interactions. Full article
(This article belongs to the Special Issue Advances in Molecular Ecology)
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