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Molecules, Volume 18, Issue 5 (May 2013), Pages 4844-6127

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Open AccessArticle The Ameliorative Effect of Sophoricoside on Mast Cell-Mediated Allergic Inflammation in Vivo and in Vitro
Molecules 2013, 18(5), 6113-6127; https://doi.org/10.3390/molecules18056113
Received: 11 March 2013 / Revised: 7 May 2013 / Accepted: 10 May 2013 / Published: 22 May 2013
Cited by 5 | Viewed by 4217 | PDF Full-text (1073 KB) | HTML Full-text | XML Full-text
Abstract
Sophoricoside exhibits numerous pharmacological effects, including anti- inflammatory and anti-cancer actions, yet the exact mechanism that accounts for the anti-allergic effects of sophoricoside is not completely understood. The aim of the present study was to elucidate whether and how sophoricoside modulates the mast
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Sophoricoside exhibits numerous pharmacological effects, including anti- inflammatory and anti-cancer actions, yet the exact mechanism that accounts for the anti-allergic effects of sophoricoside is not completely understood. The aim of the present study was to elucidate whether and how sophoricoside modulates the mast cell-mediated allergic inflammation in vitro and in vivo. We investigated the pharmacological effects of sophoricoside on both compound 48/80 or histamine-induced scratching behaviors and 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis in mice. Additionally, to find a possible explanation for the anti-inflammatory effects of sophoricoside, we evaluated the effects of sophoricoside on the production of histamine and inflammatory cytokines and activation of nuclear factor-κB (NF-κB) and caspase-1 in phorbol 12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated human mast cells (HMC-1). The finding of this study demonstrated that sophoricoside reduced compound 48/80 or histamine-induced scratching behaviors and DNCB-induced atopic dermatitis in mice. Additionally, sophoricoside inhibited the production of inflammatory cytokines as well as the activation of NF-κB and caspase-1 in stimulated HMC-1. Collectively, the findings of this study provide us with novel insights into the pharmacological actions of sophoricoside as a potential molecule for use in the treatment of allergic inflammation diseases. Full article
(This article belongs to the Special Issue Anti-Inflammatory & Anti-Allergy Agents in Medicinal Chemistry)
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Open AccessShort Note Bolaamphiphiles Derived from Alkenyl L-Rhamnosides and Alkenyl D-Xylosides: Importance of the Hydrophilic Head
Molecules 2013, 18(5), 6101-6112; https://doi.org/10.3390/molecules18056101
Received: 2 April 2013 / Revised: 22 April 2013 / Accepted: 15 May 2013 / Published: 22 May 2013
Cited by 11 | Viewed by 2587 | PDF Full-text (323 KB) | HTML Full-text | XML Full-text
Abstract
The two step synthesis of a new bolaamphiphile derived from alkenyl l-rhamnosides was described. The general synthetic strategy of bolaamphiphiles derived from l-rhamnose was based on a previous work describing the synthesis of bolaamphiphiles derived from d-xylose. The conformational properties of this new
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The two step synthesis of a new bolaamphiphile derived from alkenyl l-rhamnosides was described. The general synthetic strategy of bolaamphiphiles derived from l-rhamnose was based on a previous work describing the synthesis of bolaamphiphiles derived from d-xylose. The conformational properties of this new compound were investigated by FTIR spectroscopy in an aqueous film in order to obtain a reference for further studies about the membrane-interacting properties. Moreover, the surface activity of this new bolaamphiphile was analyzed by Langmuir balance technology and was compared with that of the analogous bolaamphiphile derived from alkenyl D-xylosides. The findings indicate that the rhamnoside-based bolaform has an increased surface activity and a better ability to form aggregates than xyloside-based one. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Low-Density Lipoprotein (LDL)-Antioxidant Biflavonoids from Garcinia madruno
Molecules 2013, 18(5), 6092-6100; https://doi.org/10.3390/molecules18056092
Received: 3 March 2013 / Revised: 25 April 2013 / Accepted: 10 May 2013 / Published: 22 May 2013
Cited by 15 | Viewed by 2735 | PDF Full-text (259 KB) | HTML Full-text | XML Full-text
Abstract
Six biflavonoids were isolated from G. madruno, one of which, 7''-O-(6''''-acetyl)-glucoside of morelloflavone, is a new compound identified on the basis of 1D, 2D NMR (HMQC and HMBC) spectroscopic methods and chemical evidence. The antioxidant activity of the biflavonoids against
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Six biflavonoids were isolated from G. madruno, one of which, 7''-O-(6''''-acetyl)-glucoside of morelloflavone, is a new compound identified on the basis of 1D, 2D NMR (HMQC and HMBC) spectroscopic methods and chemical evidence. The antioxidant activity of the biflavonoids against low-density lipoprotein (LDL) peroxidation induced with Cu2+, was studied by means of a TBARS assay. The antioxidant potential of a biflavonoid fraction (BF) was also evaluated and correlated with its biflavonoid content. The flavanone-(3→8'')-flavone biflavonoids displayed antioxidant activity, particularly morelloflavone, which was significantly more potent than quercetin, with a CE50 of 12.36 μg/mL. Lipid peroxidation, was also significantly reduced in the presence of the BF (EC50 = 11.85 μg/mL). These results suggest that the BF is an excellent antioxidant. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Substituted 3-Benzylcoumarins as Allosteric MEK1 Inhibitors: Design, Synthesis and Biological Evaluation as Antiviral Agents
Molecules 2013, 18(5), 6057-6091; https://doi.org/10.3390/molecules18056057
Received: 25 April 2013 / Revised: 10 May 2013 / Accepted: 14 May 2013 / Published: 21 May 2013
Cited by 13 | Viewed by 3180 | PDF Full-text (1413 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In order to find novel antiviral agents, a series of allosteric MEK1 inhibitors were designed and synthesized. Based on docking results, multiple optimizations were made on the coumarin scaffold. Some of the derivatives showed excellent MEK1 binding affinity in the appropriate enzymatic assays
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In order to find novel antiviral agents, a series of allosteric MEK1 inhibitors were designed and synthesized. Based on docking results, multiple optimizations were made on the coumarin scaffold. Some of the derivatives showed excellent MEK1 binding affinity in the appropriate enzymatic assays and displayed obvious inhibitory effects on the ERK pathway in a cellular assay. These compounds also significantly inhibited virus (EV71) replication in HEK293 and RD cells. Several compounds showed potential as agents for the treatment of viral infective diseases, with the most potent compound 18 showing an IC50 value of 54.57 nM in the MEK1 binding assay. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Impact of Fruit Piece Structure in Yogurts on the Dynamics of Aroma Release and Sensory Perception
Molecules 2013, 18(5), 6035-6056; https://doi.org/10.3390/molecules18056035
Received: 22 February 2013 / Revised: 2 May 2013 / Accepted: 15 May 2013 / Published: 21 May 2013
Cited by 10 | Viewed by 3253 | PDF Full-text (809 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this work was to gain insight into the effect of food formulation on aroma release and perception, both of which playing an important role in food appreciation. The quality and quantity of retronasal aroma released during food consumption affect the
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The aim of this work was to gain insight into the effect of food formulation on aroma release and perception, both of which playing an important role in food appreciation. The quality and quantity of retronasal aroma released during food consumption affect the exposure time of olfactory receptors to aroma stimuli, which can influence nutritional and hedonic characteristics, as well as consumption behaviors. In yogurts, fruit preparation formulation can be a key factor to modulate aroma stimulation. In this context, the impact of size and hardness of fruit pieces in fat-free pear yogurts was studied. Proton Transfer Reaction-Mass Spectrometry (PTR-MS) was used to allow sensitive and on-line monitoring of volatile odorous compound release in the breath during consumption. In parallel, a trained panel used sensory profile and Temporal Dominance of Sensations (TDS) methods to characterize yogurt sensory properties and their dynamic changes during consumption. Results showed that the size of pear pieces had few effects on aroma release and perception of yogurts, whereas fruit hardness significantly influenced them. Despite the fact that yogurts presented short and similar residence times in the mouth, this study showed that fruit preparation could be an interesting formulation factor to enhance exposure time to stimuli and thus modify food consumption behaviors. These results could be taken into account to formulate new products that integrate both nutritional and sensory criteria. Full article
(This article belongs to the Special Issue Flavors and Fragrances)
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Open AccessArticle An Efficient Synthesis of Aldohexose-Derived Piperidine Nitrones: Precursors of Piperidine Iminosugars
Molecules 2013, 18(5), 6021-6034; https://doi.org/10.3390/molecules18056021
Received: 7 May 2013 / Revised: 15 May 2013 / Accepted: 17 May 2013 / Published: 21 May 2013
Cited by 2 | Viewed by 2280 | PDF Full-text (251 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
D-Glucopyranose-derived and L-idopyranose-derived piperidine nitrones were synthesized in good overall yields through six-step reaction sequence starting from readily available 2,3,4,6-tetra-O-benzyl-D-glucopyranose. The method is efficient and could be general for the synthesis of aldohexose-derived piperidine nitrones which are precursors of piperidine iminosugars. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Different Analytical Approaches in Assessing Antibacterial Activity and the Purity of Commercial Lysozyme Preparations for Dairy Application
Molecules 2013, 18(5), 6008-6020; https://doi.org/10.3390/molecules18056008
Received: 9 April 2013 / Revised: 16 May 2013 / Accepted: 16 May 2013 / Published: 21 May 2013
Cited by 13 | Viewed by 3561 | PDF Full-text (418 KB) | HTML Full-text | XML Full-text
Abstract
Hen egg-white lysozyme (LSZ) is currently used in the food industry to limit the proliferation of lactic acid bacteria spoilage in the production of wine and beer, and to inhibit butyric acid fermentation in hard and extra hard cheeses (late blowing) caused by
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Hen egg-white lysozyme (LSZ) is currently used in the food industry to limit the proliferation of lactic acid bacteria spoilage in the production of wine and beer, and to inhibit butyric acid fermentation in hard and extra hard cheeses (late blowing) caused by the outgrowth of clostridial spores. The aim of this work was to evaluate how the enzyme activity in commercial preparations correlates to the enzyme concentration and can be affected by the presence of process-related impurities. Different analytical approaches, including turbidimetric assay, SDS-PAGE and HPLC were used to analyse 17 commercial preparations of LSZ marketed in different countries. The HPLC method adopted by ISO allowed the true LSZ concentration to be determined with accuracy. The turbidimetric assay was the most suitable method to evaluate LSZ activity, whereas SDS-PAGE allowed the presence of other egg proteins, which are potential allergens, to be detected. The analytical results showed that the purity of commercially available enzyme preparations can vary significantly, and evidenced the effectiveness of combining different analytical approaches in this type of control. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Anionic Calixarene-Capped Silver Nanoparticles Show Species-Dependent Binding to Serum Albumins
Molecules 2013, 18(5), 5993-6007; https://doi.org/10.3390/molecules18055993
Received: 28 February 2013 / Revised: 25 April 2013 / Accepted: 9 May 2013 / Published: 21 May 2013
Cited by 6 | Viewed by 2635 | PDF Full-text (752 KB) | HTML Full-text | XML Full-text
Abstract
The anionic calixarenes para-sulphonatocalix[4]arene and 1,3-di-Ophosphonatocalix[ 4]arene, have been used to cap silver nanoparticles. The binding of these functional particles with regard to various serum albumins (bovine serum albumin, human serum albumin, porcine serum albumin and sheep serum albumin) has been studied by
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The anionic calixarenes para-sulphonatocalix[4]arene and 1,3-di-Ophosphonatocalix[ 4]arene, have been used to cap silver nanoparticles. The binding of these functional particles with regard to various serum albumins (bovine serum albumin, human serum albumin, porcine serum albumin and sheep serum albumin) has been studied by variable temperature fluorescence spectroscopy. The quenching of the fluorescence of the proteins was shown to vary as a function of the anionic calixarene capping molecule and also as a function of the origin of the serum albumin. It is thus possible to discriminate between the different species. Full article
(This article belongs to the Special Issue Calixarenes and Resorcinarenes)
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Open AccessArticle Synthesis of Micheliolide Derivatives and Their Activities against AML Progenitor Cells
Molecules 2013, 18(5), 5980-5992; https://doi.org/10.3390/molecules18055980
Received: 27 April 2013 / Revised: 15 May 2013 / Accepted: 16 May 2013 / Published: 21 May 2013
Cited by 7 | Viewed by 2540 | PDF Full-text (268 KB) | HTML Full-text | XML Full-text
Abstract
Micheliolide (MCL) derivatives with etherification or esterification of the hydroxyl group at the C4 position were synthesized and evaluated for their activities against different acute myelogenous leukemia (AML) cell lines. These derivatives demonstrated comparable activities against AML cell lines HL-60 and doxorubicin resistant
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Micheliolide (MCL) derivatives with etherification or esterification of the hydroxyl group at the C4 position were synthesized and evaluated for their activities against different acute myelogenous leukemia (AML) cell lines. These derivatives demonstrated comparable activities against AML cell lines HL-60 and doxorubicin resistant cell line HL-60/A. As to multi-drug resistant AML progenitor cells KG-1a, MCL and some of its derivatives maintained significant activities, and only 1.1–2.7 fold activity reductions were observed when compared with the activities against HL-60, while doxorubicin showed 20-fold activity reduction. Our study demonstrated that the C4 hydroxyl group of MCL might not only be a suitable position for structural modifications, but also be a starting point for the design of appropriate molecular probes to explore the specific targets in the progenitor cell line KG-1a. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Interactive Effect of Salicylic Acid on Some Physiological Features and Antioxidant Enzymes Activity in Ginger (Zingiber officinale Roscoe)
Molecules 2013, 18(5), 5965-5979; https://doi.org/10.3390/molecules18055965
Received: 3 April 2013 / Revised: 13 May 2013 / Accepted: 13 May 2013 / Published: 21 May 2013
Cited by 17 | Viewed by 2857 | PDF Full-text (421 KB) | HTML Full-text | XML Full-text
Abstract
The effect of foliar salicylic acid (SA) applications (10−3 and 10−5 M) on activities of nitrate reductase, guaiacol peroxidase (POD), superoxide dismutases (SOD), catalase (CAT) and proline enzymes and physiological parameters was evaluated in two ginger varieties (Halia Bentong and Halia
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The effect of foliar salicylic acid (SA) applications (10−3 and 10−5 M) on activities of nitrate reductase, guaiacol peroxidase (POD), superoxide dismutases (SOD), catalase (CAT) and proline enzymes and physiological parameters was evaluated in two ginger varieties (Halia Bentong and Halia Bara) under greenhouse conditions. In both varieties, tested treatments generally enhanced photosynthetic rate and total dry weight. Photosynthetic rate increases were generally accompanied by increased or unchanged stomatal conductance levels, although intercellular CO2 concentrations of treated plants were typically lower than in controls. Lower SA concentrations were generally more effective in enhancing photosynthetic rate and plant growth. Exogenous application of SA increased antioxidant enzyme activities and proline content; the greatest responses were obtained in plants sprayed with 10–5 M SA, with significant increases observed in CAT (20.1%), POD (45.2%), SOD (44.1%) and proline (43.1%) activities. Increased CAT activity in leaves is naturally expected to increase photosynthetic efficiency and thus net photosynthesis by maintaining a constant CO2 supply. Our results support the idea that low SA concentrations (10–5 M) may induce nitrite reductase synthesis by mobilizing intracellular NO3 and can provide protection to nitrite reductase degradation in vivo in the absence of NO3–. Observed positive correlations among proline, SOD, CAT and POD activities in the studied varieties suggest that increased SOD activity was accompanied by increases in CAT and POD activities because of the high demands of H2O2 quenching. Full article
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Open AccessArticle Green Biosynthesis and Characterization of Magnetic Iron Oxide (Fe3O4) Nanoparticles Using Seaweed (Sargassum muticum) Aqueous Extract
Molecules 2013, 18(5), 5954-5964; https://doi.org/10.3390/molecules18055954
Received: 8 April 2013 / Revised: 14 May 2013 / Accepted: 15 May 2013 / Published: 21 May 2013
Cited by 119 | Viewed by 6734 | PDF Full-text (576 KB) | HTML Full-text | XML Full-text
Abstract
The synthesis of nanoparticles has become a matter of great interest in recent times due to their various advantageous properties and applications in a variety of fields. The exploitation of different plant materials for the biosynthesis of nanoparticles is considered a green technology
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The synthesis of nanoparticles has become a matter of great interest in recent times due to their various advantageous properties and applications in a variety of fields. The exploitation of different plant materials for the biosynthesis of nanoparticles is considered a green technology because it does not involve any harmful chemicals. In this study, iron oxide nanoparticles (Fe3O4-NPs) were synthesized using a rapid, single step and completely green biosynthetic method by reduction of ferric chloride solution with brown seaweed (BS, Sargassum muticum) water extract containing sulphated polysaccharides as a main factor which acts as reducing agent and efficient stabilizer. The structural and properties of the Fe3O4-NPs were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy (FESEM), energy dispersive X-ray fluorescence spectrometry (EDXRF), vibrating sample magnetometry (VSM) and transmission electron microscopy. The average particle diameter as determined by TEM was found to be 18 ± 4 nm. X-ray diffraction showed that the nanoparticles are crystalline in nature, with a cubic shape. The nanoparticles synthesized through this biosynthesis method can potentially useful in various applications. Full article
(This article belongs to the Special Issue Nano-catalysts and Nano-technologies for Green Organic Synthesis)
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Open AccessArticle Dimeric Labdane Diterpenes: Synthesis and Antiproliferative Effects
Molecules 2013, 18(5), 5936-5953; https://doi.org/10.3390/molecules18055936
Received: 15 April 2013 / Revised: 29 April 2013 / Accepted: 13 May 2013 / Published: 21 May 2013
Cited by 14 | Viewed by 3370 | PDF Full-text (241 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Several diterpenes with the labdane skeleton show biological activity, including antiproliferative effects. Most of the research work on bioactive labdanes has been carried out on naturally occurring diterpenes and semisynthetic derivatives, but much less is known on the effects of diterpene dimers. The
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Several diterpenes with the labdane skeleton show biological activity, including antiproliferative effects. Most of the research work on bioactive labdanes has been carried out on naturally occurring diterpenes and semisynthetic derivatives, but much less is known on the effects of diterpene dimers. The aim of the present work was to synthesize dimeric diterpenes from the labdane imbricatolic acid using esters, ethers and the triazole ring as linkers. Some 18 new derivatives were prepared and the compounds were evaluated for antiproliferative activity on human normal fibroblasts (MRC-5) and the following human tumor cell lines: AGS, SK-MES-1, J82 and HL-60. The diethers 8–10, differing in the number of CH2 units in the linker, presented better antiproliferative activity with a maximum effect for the derivative 9. The best antiproliferative effect against HL-60 cells was found for compounds 3 and 17, with IC50 values of 22.3 and 23.2 μM, lower than that found for the reference compound etoposide (2.23 μM). The compounds 9, 17 and 11 were the most active derivatives towards AGS cells with IC50 values of 17.8, 23.4 and 26.1 μM. A free carboxylic acid function seems relevant for the effect as several of the compounds showed less antiproliferative effect after methylation. Full article
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Open AccessReview Metabolites from Alternaria Fungi and Their Bioactivities
Molecules 2013, 18(5), 5891-5935; https://doi.org/10.3390/molecules18055891
Received: 18 March 2013 / Revised: 6 May 2013 / Accepted: 16 May 2013 / Published: 21 May 2013
Cited by 60 | Viewed by 4037 | PDF Full-text (362 KB) | HTML Full-text | XML Full-text
Abstract
Alternaria is a cosmopolitan fungal genus widely distributing in soil and organic matter. It includes saprophytic, endophytic and pathogenic species. At least 268 metabolites from Alternaria fungi have been reported in the past few decades. They mainly include nitrogen-containing metabolites, steroids, terpenoids, pyranones,
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Alternaria is a cosmopolitan fungal genus widely distributing in soil and organic matter. It includes saprophytic, endophytic and pathogenic species. At least 268 metabolites from Alternaria fungi have been reported in the past few decades. They mainly include nitrogen-containing metabolites, steroids, terpenoids, pyranones, quinones, and phenolics. This review aims to briefly summarize the structurally different metabolites produced by Alternaria fungi, as well as their occurrences, biological activities and functions. Some considerations related to synthesis, biosynthesis, production and applications of the metabolites from Alternaria fungi are also discussed. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessReview Gold Nanoparticle Contrast Agents in Advanced X-ray Imaging Technologies
Molecules 2013, 18(5), 5858-5890; https://doi.org/10.3390/molecules18055858
Received: 12 March 2013 / Revised: 30 April 2013 / Accepted: 14 May 2013 / Published: 17 May 2013
Cited by 39 | Viewed by 4381 | PDF Full-text (6320 KB) | HTML Full-text | XML Full-text
Abstract
Recently, there has been significant progress in the field of soft- and hard-X-ray imaging for a wide range of applications, both technically and scientifically, via developments in sources, optics and imaging methodologies. While one community is pursuing extensive applications of available X-ray tools,
[...] Read more.
Recently, there has been significant progress in the field of soft- and hard-X-ray imaging for a wide range of applications, both technically and scientifically, via developments in sources, optics and imaging methodologies. While one community is pursuing extensive applications of available X-ray tools, others are investigating improvements in techniques, including new optics, higher spatial resolutions and brighter compact sources. For increased image quality and more exquisite investigation on characteristic biological phenomena, contrast agents have been employed extensively in imaging technologies. Heavy metal nanoparticles are excellent absorbers of X-rays and can offer excellent improvements in medical diagnosis and X-ray imaging. In this context, the role of gold (Au) is important for advanced X-ray imaging applications. Au has a long-history in a wide range of medical applications and exhibits characteristic interactions with X-rays. Therefore, Au can offer a particular advantage as a tracer and a contrast enhancer in X-ray imaging technologies by sensing the variation in X-ray attenuation in a given sample volume. This review summarizes basic understanding on X-ray imaging from device set-up to technologies. Then this review covers recent studies in the development of X-ray imaging techniques utilizing gold nanoparticles (AuNPs) and their relevant applications, including two- and three-dimensional biological imaging, dynamical processes in a living system, single cell-based imaging and quantitative analysis of circulatory systems and so on. In addition to conventional medical applications, various novel research areas have been developed and are expected to be further developed through AuNP-based X-ray imaging technologies. Full article
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Open AccessReview Vasodilator Compounds Derived from Plants and Their Mechanisms of Action
Molecules 2013, 18(5), 5814-5857; https://doi.org/10.3390/molecules18055814
Received: 19 April 2013 / Revised: 24 April 2013 / Accepted: 7 May 2013 / Published: 17 May 2013
Cited by 15 | Viewed by 3684 | PDF Full-text (373 KB) | HTML Full-text | XML Full-text
Abstract
The present paper reviews vasodilator compounds isolated from plants that were reported in the past 22 years (1990 to 2012) and the different mechanisms of action involved in their vasodilator effects. The search for reports was conducted in a comprehensive manner, intending to
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The present paper reviews vasodilator compounds isolated from plants that were reported in the past 22 years (1990 to 2012) and the different mechanisms of action involved in their vasodilator effects. The search for reports was conducted in a comprehensive manner, intending to encompass those metabolites with a vasodilator effect whose mechanism of action involved both vascular endothelium and arterial smooth muscle. The results obtained from our bibliographic search showed that over half of the isolated compounds have a mechanism of action involving the endothelium. Most of these bioactive metabolites cause vasodilation either by activating the nitric oxide/cGMP pathway or by blocking voltage-dependent calcium channels. Moreover, it was found that many compounds induced vasodilation by more than one mechanism. This review confirms that secondary metabolites, which include a significant group of compounds with extensive chemical diversity, are a valuable source of new pharmaceuticals useful for the treatment and prevention of cardiovascular diseases. Full article
(This article belongs to the Special Issue Bioassay-Guided Isolation of Natural Products)
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Open AccessCommunication Dried Root of Rehmannia glutinosa Prevents Bone Loss in Ovariectomized Rats
Molecules 2013, 18(5), 5804-5813; https://doi.org/10.3390/molecules18055804
Received: 7 April 2013 / Revised: 10 May 2013 / Accepted: 14 May 2013 / Published: 17 May 2013
Cited by 27 | Viewed by 3350 | PDF Full-text (478 KB) | HTML Full-text | XML Full-text
Abstract
Dried root of Rehmannia glutinosa is a kidney-tonifying herbal medicine with a long history of safe use in traditional folk medicine for the treatment of joint diseases. This study was conducted to investigate prevention of bone loss by a standardized dried root of
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Dried root of Rehmannia glutinosa is a kidney-tonifying herbal medicine with a long history of safe use in traditional folk medicine for the treatment of joint diseases. This study was conducted to investigate prevention of bone loss by a standardized dried root of R. glutinosa in an ovariectomized (OVX) rat model of osteoporosis. The OVX groups were divided into five groups treated with distilled water, 17β-estradiol (E2 10 µg/kg, once daily, i.p) and dried root of R. glutinosa extracts (DRGE 30, 100, and 300 mg/kg, twice daily, p.o) for eight weeks. We measured the body, organs, and uterus weights, and femur and lumbar vertebrae bone mineral density (BMD), serum alkaline phosphatase (ALP), estradiol levels. The treatments with DRGE 300 mg/kg significantly inhibited BMD decrease in the femur and lumbar (17.5% and 16.4%, p < 0.05, respectively) by OVX without affecting the body, organs, and uterus weights. Also, serum ALP level in the DRGE 300 mg/kg treated group was significantly decreased, but the estradiol level did not change in serum of the DRGE 300 mg/kg treated group. These results show that DRGE is able to prevent OVX-induced bone loss without influencing hormones such as estrogen. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Effect of Leguminous Lectins on the Growth of Rhizobium tropici CIAT899
Molecules 2013, 18(5), 5792-5803; https://doi.org/10.3390/molecules18055792
Received: 8 March 2013 / Accepted: 14 May 2013 / Published: 17 May 2013
Cited by 3 | Viewed by 2584 | PDF Full-text (870 KB) | HTML Full-text | XML Full-text
Abstract
Rhizobium tropici is a Gram-negative bacterium that induces nodules and fixed atmospheric nitrogen in symbiotic association with Phaseolus vulgaris (common bean) and some other leguminous species. Lectins are proteins that specifically bind to carbohydrates and, consequently, modulate different biological functions. In this study,
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Rhizobium tropici is a Gram-negative bacterium that induces nodules and fixed atmospheric nitrogen in symbiotic association with Phaseolus vulgaris (common bean) and some other leguminous species. Lectins are proteins that specifically bind to carbohydrates and, consequently, modulate different biological functions. In this study, the d-glucose/ d-mannose-binding lectins (from seeds of Dioclea megacarpa, D. rostrata and D. violacea) and D-galactose-binding lectins (from seeds of Bauhinia variegata, Erythina velutina and Vatairea macrocarpa) were purified using chromatographic techniques and evaluated for their effect on the growth of R. tropici CIAT899. All lectins were assayed with a satisfactory degree of purity according to SDS-PAGE analysis, and stimulated bacterial growth; in particular, the Dioclea rostrata lectin was the most active among all tested proteins. As confirmed in the present study, both d-galactose- and d-glucose/d-mannose-binding lectins purified from the seeds of leguminous plants may be powerful biotechnological tools to stimulate the growth of R. tropici CIAT99, thus improving symbiotic interaction between rhizobia and common bean and, hence, the production of this field crop. Full article
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Open AccessArticle Effects of Polysaccharides from Different Species of Dendrobium (Shihu) on Macrophage Function
Molecules 2013, 18(5), 5779-5791; https://doi.org/10.3390/molecules18055779
Received: 12 April 2013 / Revised: 3 May 2013 / Accepted: 13 May 2013 / Published: 17 May 2013
Cited by 29 | Viewed by 3485 | PDF Full-text (1378 KB) | HTML Full-text | XML Full-text
Abstract
Dendrobium spp. are precious medicinal plants, used in China for thousands of years as health foods and nutrients. Polysaccharides are the main effective ingredients in Dendrobium plants. In this study, the chemical characteristics and the effects of crude polysaccharides (CPs) from five species
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Dendrobium spp. are precious medicinal plants, used in China for thousands of years as health foods and nutrients. Polysaccharides are the main effective ingredients in Dendrobium plants. In this study, the chemical characteristics and the effects of crude polysaccharides (CPs) from five species of Dendrobium on macrophage function were investigated and compared in vitro for the first time. Chemical characteristic studies showed that CPs from different species of Dendrobium were diverse, displaying widely varied Mw distributions and molar ratios of monosaccharides. Their effects on macrophage functions, such as promoting phagocytosis, release of NO and cytokines IL-1α, IL-6, IL-10 and TNF-α, were also different. Moreover, CPs from D. officinale, especially collected from Yunnan Province, exerted the strongest immunomodulatory activities and could be explored as a novel potential functional food. The diverse chemical characteristics of CPs from different species of Dendrobium might contribute to their varied effects on macrophage functions, which should be further investigated. Full article
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Open AccessArticle Anti-Infective Potential of Marine Invertebrates and Seaweeds from the Brazilian Coast
Molecules 2013, 18(5), 5761-5778; https://doi.org/10.3390/molecules18055761
Received: 28 March 2013 / Revised: 3 May 2013 / Accepted: 10 May 2013 / Published: 16 May 2013
Cited by 18 | Viewed by 3646 | PDF Full-text (320 KB) | HTML Full-text | XML Full-text
Abstract
This manuscript describes the evaluation of anti-infective potential in vitro of organic extracts from nine sponges, one ascidian, two octocorals, one bryozoan, and 27 seaweed species collected along the Brazilian coast. Antimicrobial activity was tested against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC
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This manuscript describes the evaluation of anti-infective potential in vitro of organic extracts from nine sponges, one ascidian, two octocorals, one bryozoan, and 27 seaweed species collected along the Brazilian coast. Antimicrobial activity was tested against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922) and Candida albicans (ATCC 10231) by the disk diffusion method. Antiprotozoal activity was evaluated against Leishmania braziliensis (MHOM/BR/96/LSC96-H3) promastigotes and Trypanosoma cruzi (MHOM/BR/00/Y) epimastigotes by MTT assay. Activity against intracellular amastigotes of T. cruzi and L. brasiliensis in murine macrophages was also evaluated. Antiviral activity was tested against Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the plaque number reduction assay (IC50). Cytotoxicity on VERO cells was evaluated by the MTT assay (CC50). The results were expressed as SI = CC50/IC50. The most promising antimicrobial results were obtained against S. aureus and C. albicans with Dragmacidon reticulatum. Among the seaweeds, only Osmundaria obtusiloba showed moderate activity against P. aeruginosa. Concerning antiprotozoal activity, Bugula neritina, Carijoa riseii, Dragmaxia anomala and Haliclona (Halichoclona) sp. showed the most interesting results, mainly against extracellular promastigote forms of L. braziliensis (66, 35.9, 97.2, and 43.6% inhibition, respectively). Moreover, six species of seaweeds Anadyomene saldanhae, Caulerpa cupressoides, Canistrocarpus cervicornis, Dictyota sp., Ochtodes secundiramea, and Padina sp. showed promising results against L. braziliensis (87.9, 51.7, 85.9, 93.3, 99.7, and 80.9% inhibition, respectively), and only Dictyota sp. was effective against T. cruzi (60.4% inhibition). Finally, the antiherpes activity was also evaluated, with Haliclona (Halichoclona) sp. and Petromica citrina showing the best results (SI = 11.9 and SI > 5, respectively). All the active extracts deserve special attention in further studies to chemically characterize the bioactive compounds, and to perform more refined biological assays. Full article
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Open AccessArticle Synthesis and Characterization of Oil-Chitosan Composite Spheres
Molecules 2013, 18(5), 5749-5760; https://doi.org/10.3390/molecules18055749
Received: 1 April 2013 / Revised: 29 April 2013 / Accepted: 9 May 2013 / Published: 16 May 2013
Cited by 9 | Viewed by 3505 | PDF Full-text (968 KB) | HTML Full-text | XML Full-text
Abstract
Oil-chitosan composite spheres were synthesized by encapsulation of sunflower seed oil in chitosan droplets, dropping into NaOH solution and in situ solidification. Hydrophilic materials (i.e., iron oxide nanoparticles) and lipophilic materials (i.e., rhodamine B or epirubicin) could be encapsulated
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Oil-chitosan composite spheres were synthesized by encapsulation of sunflower seed oil in chitosan droplets, dropping into NaOH solution and in situ solidification. Hydrophilic materials (i.e., iron oxide nanoparticles) and lipophilic materials (i.e., rhodamine B or epirubicin) could be encapsulated simultaneously in the spheres in a one step process. The diameters of the prepared spheres were 2.48 ± 0.11 mm (pure chitosan spheres), 2.31 ± 0.08 mm (oil-chitosan composites), 1.49 ± 0.15 mm (iron-oxide embedded oil-chitosan composites), and 1.69 ± 0.1 mm (epirubicin and iron oxide encapsulated oil-chitosan composites), respectively. Due to their superparamagnetic properties, the iron-oxide embedded oil-chitosan composites could be guided by a magnet. A lipophilic drug (epirubicin) could be loaded in the spheres with encapsulation rate measured to be 72.25%. The lipophilic fluorescent dye rhodamine B was also loadable in the spheres with red fluorescence being observed under a fluorescence microscope. We have developed a novel approach to an in situ process for fabricating oil-chitosan composite spheres with dual encapsulation properties, which are potential multifunctional drug carriers. Full article
(This article belongs to the Special Issue Chitins and Chitosans)
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Open AccessArticle Production of Flavours and Fragrances via Bioreduction of (4R)-(-)-Carvone and (1R)-(-)-Myrtenal by Non-Conventional Yeast Whole-Cells
Molecules 2013, 18(5), 5736-5748; https://doi.org/10.3390/molecules18055736
Received: 29 March 2013 / Revised: 29 April 2013 / Accepted: 10 May 2013 / Published: 16 May 2013
Cited by 14 | Viewed by 3446 | PDF Full-text (229 KB) | HTML Full-text | XML Full-text
Abstract
As part of a program aiming at the selection of yeast strains which might be of interest as sources of natural flavours and fragrances, the bioreduction of (4R)-(−)-carvone and (1R)-(−)-myrtenal by whole-cells of non-conventional yeasts (NCYs) belonging to the
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As part of a program aiming at the selection of yeast strains which might be of interest as sources of natural flavours and fragrances, the bioreduction of (4R)-(−)-carvone and (1R)-(−)-myrtenal by whole-cells of non-conventional yeasts (NCYs) belonging to the genera Candida, Cryptococcus, Debaryomyces, Hanseniaspora, Kazachstania, Kluyveromyces, Lindnera, Nakaseomyces, Vanderwaltozyma and Wickerhamomyces was studied. Volatiles produced were sampled by means of headspace solid-phase microextraction (SPME) and the compounds were analysed and identified by gas chromatography–mass spectroscopy (GC-MS). Yields (expressed as % of biotransformation) varied in dependence of the strain. The reduction of both (4R)-(−)-carvone and (1R)-(−)-myrtenal were catalyzed by some ene-reductases (ERs) and/or carbonyl reductases (CRs), which determined the formation of (1R,4R)-dihydrocarvone and (1R)-myrtenol respectively, as main flavouring products. The potential of NCYs as novel whole-cell biocatalysts for selective biotransformation of electron-poor alkenes for producing flavours and fragrances of industrial interest is discussed. Full article
(This article belongs to the Special Issue Flavors and Fragrances)
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Open AccessArticle Four New Citrinin Derivatives from a Marine-Derived Penicillium sp. Fungal Strain
Molecules 2013, 18(5), 5723-5735; https://doi.org/10.3390/molecules18055723
Received: 11 April 2013 / Revised: 9 May 2013 / Accepted: 10 May 2013 / Published: 16 May 2013
Cited by 15 | Viewed by 3074 | PDF Full-text (307 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Four new citrinin derivatives, including two citrinin dimers and two citrinin monomer derivatives, were isolated and identified from a marine-derived fungal strain Penicillium sp. ML226 along with six known related compounds. Their structures were elucidated by spectroscopic and chemical methods. The new compounds
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Four new citrinin derivatives, including two citrinin dimers and two citrinin monomer derivatives, were isolated and identified from a marine-derived fungal strain Penicillium sp. ML226 along with six known related compounds. Their structures were elucidated by spectroscopic and chemical methods. The new compounds showed modest cytotoxic activity against HepG-2 cell line and weak antimicrobial activity against Staphylococcus aureus. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Virtual Screening and Structure-Based Discovery of Indole Acylguanidines as Potent β-secretase (BACE1) Inhibitors
Molecules 2013, 18(5), 5706-5722; https://doi.org/10.3390/molecules18055706
Received: 31 January 2013 / Revised: 9 April 2013 / Accepted: 9 May 2013 / Published: 16 May 2013
Cited by 9 | Viewed by 3545 | PDF Full-text (1246 KB) | HTML Full-text | XML Full-text
Abstract
Proteolytic cleavage of amyloid precursor protein by β-secretase (BACE1) is a key step in generating the N-terminal of β-amyloid (Aβ), which further forms into amyloid plaques that are considered as the hallmark of Alzheimer’s disease. Inhibitors of BACE1 can reduce the levels
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Proteolytic cleavage of amyloid precursor protein by β-secretase (BACE1) is a key step in generating the N-terminal of β-amyloid (Aβ), which further forms into amyloid plaques that are considered as the hallmark of Alzheimer’s disease. Inhibitors of BACE1 can reduce the levels of Aβ and thus have a therapeutic potential for treating the disease. We report here the identification of a series of small molecules bearing an indole acylguanidine core structure as potent BACE1 inhibitors. The initial weak fragment was discovered by virtual screening, and followed with a hit-to-lead optimization. With the aid of co-crystal structures of two discovered inhibitors (compounds 19 and 25) with BACE1, we explored the SAR around the indole and aryl groups, and obtained several BACE1 inhibitors about 1,000-fold more potent than the initial fragment hit. Accompanying the lead optimization, a previously under-explored sub-site opposite the flap loop was redefined as a potential binding site for later BACE1 inhibitor design. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle A Novel Multi-Component Reaction to Imidazo[4,5-g]-quinazolines
Molecules 2013, 18(5), 5697-5705; https://doi.org/10.3390/molecules18055697
Received: 19 April 2013 / Revised: 8 May 2013 / Accepted: 10 May 2013 / Published: 16 May 2013
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Abstract
The trace impurities discovered after extended storage of a 5-amino- benzimidazole library were determined as imidazo[4,5-g]quinazoline derivatives by extensive spectroscopic data analysis. The formation of this highly aromatic heterocyclic ring involved a novel multi-component reaction, using which several novel compounds were prepared. Its
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The trace impurities discovered after extended storage of a 5-amino- benzimidazole library were determined as imidazo[4,5-g]quinazoline derivatives by extensive spectroscopic data analysis. The formation of this highly aromatic heterocyclic ring involved a novel multi-component reaction, using which several novel compounds were prepared. Its mechanism was deduced as a cascade of chemical transformations, including the formation of a Schiff’s base, intramolecular hetero-Diels-Alder reaction, defluorination and dehydrogenation. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Identification of Insecticidal Constituents of the Essential Oil of Acorus calamus Rhizomes against Liposcelis bostrychophila Badonnel
Molecules 2013, 18(5), 5684-5696; https://doi.org/10.3390/molecules18055684
Received: 20 March 2013 / Revised: 6 May 2013 / Accepted: 13 May 2013 / Published: 15 May 2013
Cited by 42 | Viewed by 3415 | PDF Full-text (249 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this research was to determine the chemical composition of the essential oil of Acorus calamus rhizomes, its insecticidal activity against the booklouse, (Liposcelis bostrychophila) and to isolate any insecticidal constituents from the essential oil. The essential oil of
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The aim of this research was to determine the chemical composition of the essential oil of Acorus calamus rhizomes, its insecticidal activity against the booklouse, (Liposcelis bostrychophila) and to isolate any insecticidal constituents from the essential oil. The essential oil of A. calamus rhizomes was obtained by hydrodistillation and analyzed by GC-FID and GC-MS. A total of 32 components of the essential oil of A. calamus rhizomes was identified and the principal compounds in the essential oil were determined to be α-asarone (50.09%), (E)-methylisoeugenol (14.01%), and methyleugenol (8.59%), followed by β-asarone (3.51%), α-cedrene (3.09%) and camphor (2.42%). Based on bioactivity-guided fractionation, the three active constituents were isolated from the essential oil and identified as methyleugenol, (E)-methylisoeugenol and α-asarone. The essential oil exhibited contact toxicity against L. bostrychophila with an LD50 value of 100.21 µg/cm2 while three constituent compounds, α-asarone, methyleugenol, and (E)-methylisoeugenol had LD50 values of 125.73 µg/cm2, 103.22 µg/cm2 and 55.32 µg/cm2, respectively. Methyleugenol and (E)-methylisoeugenol possessed fumigant toxicity against L. bostrychophila adults with LC50 values of 92.21 μg/L air and 143.43 μg/L air, respectively, while the crude essential oil showed an LC50 value of 392.13 μg/L air. The results indicate that the essential oil of A. calamus rhizomes and its constituent compounds have potential for development into natural fumigants/insecticides for control of the booklice. Full article
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Open AccessArticle Effects of Chirality on the Antifungal Potency of Methylated Succinimides Obtained by Aspergillus fumigatus Biotransformations. Comparison with Racemic Ones
Molecules 2013, 18(5), 5669-5683; https://doi.org/10.3390/molecules18055669
Received: 24 April 2013 / Revised: 13 May 2013 / Accepted: 13 May 2013 / Published: 15 May 2013
Cited by 10 | Viewed by 2504 | PDF Full-text (329 KB) | HTML Full-text | XML Full-text
Abstract
Eighteen (3R) and (3R,4R)-N-phenyl-, N-phenylalkyl and N-arylsuccinimides were prepared with high enantioselectivity by biotransformation of maleimides with A. fumigatus. This environmentally friendly, clean and economical procedure was performed by the whole-cell fungal
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Eighteen (3R) and (3R,4R)-N-phenyl-, N-phenylalkyl and N-arylsuccinimides were prepared with high enantioselectivity by biotransformation of maleimides with A. fumigatus. This environmentally friendly, clean and economical procedure was performed by the whole-cell fungal bioconversion methodology. Their corresponding eighteen racemic succinimides were prepared instead by synthetic methods. Both, the racemic and the chiral succinimides were tested simultaneously by the microbroth dilution method of CLSI against a panel of human opportunistic pathogenic fungi of clinical importance. Chiral succinimides showed higher antifungal activity than the corresponding racemic ones and the differences in activity were established by statistical methods. The bottlenecks for developing chiral drugs are how to obtain them through a low-cost procedure and with high enantiomeric excess. Results presented here accomplish both these objectives, opening an avenue for the development of asymmetric succinimides as new antifungal drugs for pharmaceutical use. Full article
(This article belongs to the Section Molecular Diversity)
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Open AccessArticle Photophysical Studies of a New Water Soluble Indocarbocyanine Dye Adsorbed onto Microcrystalline Cellulose and beta-Cyclodextrin
Molecules 2013, 18(5), 5648-5668; https://doi.org/10.3390/molecules18055648
Received: 21 January 2013 / Revised: 26 April 2013 / Accepted: 9 May 2013 / Published: 15 May 2013
Cited by 5 | Viewed by 2835 | PDF Full-text (1001 KB) | HTML Full-text | XML Full-text
Abstract
A water-soluble indocarbocyanine dye was synthesized and its photophysics were studied for the first time on two solid hosts, microcrystalline cellulose and b-cyclodextrin, as well as in homogeneous media. The inclusion of the indocarbocyanine moiety onto microcrystalline cellulose increased the dye aggregation with
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A water-soluble indocarbocyanine dye was synthesized and its photophysics were studied for the first time on two solid hosts, microcrystalline cellulose and b-cyclodextrin, as well as in homogeneous media. The inclusion of the indocarbocyanine moiety onto microcrystalline cellulose increased the dye aggregation with both H and J aggregates being formed. Adsorption on b-cyclodextrin enhanced aggregation in a similar way. The fluorescence quantum yields were determined for the powdered samples of the cyanine dye on the two hosts and a significant increase was observed relative to homogeneous solution. A remarkable concentration dependence was also detected in both cases. A lifetime distribution analysis has shown that the indocarbocyanine dye mainly occupies the amorphous part of cellulose and is not entrapped in the crystalline part of this host. In the b-CD case, the adsorption occurs outside the host cavity. In both hosts a strong concentration quenching effect is observed and only monomers emit. Both adsorptions may be explained by stereochemical constraints imposed by the two long sulphoethyl tails linked to nitrogen atoms of the indocarbocyanine dye. Full article
(This article belongs to the Special Issue New Trends in Photochemistry)
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Open AccessReview Chitosan for Gene Delivery and Orthopedic Tissue Engineering Applications
Molecules 2013, 18(5), 5611-5647; https://doi.org/10.3390/molecules18055611
Received: 1 April 2013 / Revised: 2 May 2013 / Accepted: 6 May 2013 / Published: 15 May 2013
Cited by 67 | Viewed by 5519 | PDF Full-text (1180 KB) | HTML Full-text | XML Full-text
Abstract
Gene therapy involves the introduction of foreign genetic material into cells in order exert a therapeutic effect. The application of gene therapy to the field of orthopaedic tissue engineering is extremely promising as the controlled release of therapeutic proteins such as bone morphogenetic
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Gene therapy involves the introduction of foreign genetic material into cells in order exert a therapeutic effect. The application of gene therapy to the field of orthopaedic tissue engineering is extremely promising as the controlled release of therapeutic proteins such as bone morphogenetic proteins have been shown to stimulate bone repair. However, there are a number of drawbacks associated with viral and synthetic non-viral gene delivery approaches. One natural polymer which has generated interest as a gene delivery vector is chitosan. Chitosan is biodegradable, biocompatible and non-toxic. Much of the appeal of chitosan is due to the presence of primary amine groups in its repeating units which become protonated in acidic conditions. This property makes it a promising candidate for non-viral gene delivery. Chitosan-based vectors have been shown to transfect a number of cell types including human embryonic kidney cells (HEK293) and human cervical cancer cells (HeLa). Aside from its use in gene delivery, chitosan possesses a range of properties that show promise in tissue engineering applications; it is biodegradable, biocompatible, has anti-bacterial activity, and, its cationic nature allows for electrostatic interaction with glycosaminoglycans and other proteoglycans. It can be used to make nano- and microparticles, sponges, gels, membranes and porous scaffolds. Chitosan has also been shown to enhance mineral deposition during osteogenic differentiation of MSCs in vitro. The purpose of this review is to critically discuss the use of chitosan as a gene delivery vector with emphasis on its application in orthopedic tissue engineering. Full article
(This article belongs to the Special Issue Chitins and Chitosans)
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Open AccessArticle Development of a New Positron Emission Tomography Tracer for Targeting Tumor Angiogenesis: Synthesis, Small Animal Imaging, and Radiation Dosimetry
Molecules 2013, 18(5), 5594-5610; https://doi.org/10.3390/molecules18055594
Received: 7 March 2013 / Revised: 25 April 2013 / Accepted: 10 May 2013 / Published: 15 May 2013
Cited by 7 | Viewed by 3082 | PDF Full-text (1824 KB) | HTML Full-text | XML Full-text
Abstract
Angiogenesis plays a key role in cancer progression and correlates with disease aggressiveness and poor clinical outcomes. Affinity ligands discovered by screening phage display random peptide libraries can be engineered to molecularly target tumor blood vessels for noninvasive imaging and early detection of
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Angiogenesis plays a key role in cancer progression and correlates with disease aggressiveness and poor clinical outcomes. Affinity ligands discovered by screening phage display random peptide libraries can be engineered to molecularly target tumor blood vessels for noninvasive imaging and early detection of tumor aggressiveness. In this study, we tested the ability of a phage-display-selected peptide sequence recognizing specifically bone marrow- derived pro-angiogenic tumor-homing cells, the QFP-peptide, radiolabeled with 64Cu radioisotope to selectively image tumor vasculature in vivo by positron emission tomography (PET). To prepare the targeted PET tracer we modified QFP-phage with the DOTA chelator and radiolabeled the purified QFP-phage-DOTA intermediate with 64Cu to obtain QFP-targeted radioconjugate with high radiopharmaceutical yield and specific activity. We evaluated the new PET tracer in vivo in a subcutaneous (s.c.) Lewis lung carcinoma (LLC) mouse model and conducted tissue distribution, small animal PET/CT imaging study, autoradiography, histology, fluorescence imaging, and dosimetry assessments. The results from this study show that, in the context of the s.c. LLC immunocompetent mouse model, the QFP-tracer can target tumor blood vessels selectively. However, further optimization of the biodistribution and dosimetry profile of the tracer is necessary to ensure efficient radiopharmaceutical applications enabled by the biological specificity of the QFP-peptide. Full article
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Open AccessArticle Hexachlorocyclotriphosphazene (HCCP)-Mediated Direct Formation of Thioethers and Ethers from Quinazolin-4(3H)-ones
Molecules 2013, 18(5), 5580-5593; https://doi.org/10.3390/molecules18055580
Received: 25 March 2013 / Revised: 12 May 2013 / Accepted: 13 May 2013 / Published: 15 May 2013
Cited by 3 | Viewed by 2496 | PDF Full-text (214 KB) | HTML Full-text | XML Full-text
Abstract
A hexachlorocyclotriphosphazene (HCCP)-mediated direct formation of quinazoline (thio)ethers from quinazolin-4(3H)-ones has been developed. Treatment of quinazolin-4(3H)-ones with HCCP, diisopropylethylamine (DIPEA), and thiophenols resulted in formation of the corresponding 4-arylthioquinazoline derivatives in moderate to excellent yields. This method has also
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A hexachlorocyclotriphosphazene (HCCP)-mediated direct formation of quinazoline (thio)ethers from quinazolin-4(3H)-ones has been developed. Treatment of quinazolin-4(3H)-ones with HCCP, diisopropylethylamine (DIPEA), and thiophenols resulted in formation of the corresponding 4-arylthioquinazoline derivatives in moderate to excellent yields. This method has also been utilized to prepare 4-aryloxyquinazoline and 4-alkoxyquinazoline derivatives using phenols and sodium alkoxides as the nucleophiles. Full article
(This article belongs to the Section Organic Chemistry)
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