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Plass Tilman - - 2012
Under tension: A set of genetically encoded unnatural amino acids can be used for biocompatible site-specific labeling of proteins with fluorogenic dyes. The new compounds have norbornene and trans-cyclooctene units that react with tetrazine derivatives in an inverse-electron-demand Diels-Alder cycloaddition (left in picture). The technique offers fast labeling that is ...
Ishida Yasuyuki - - 2012
Thermally assisted hydrolysis and methylation-gas chromatography (THM-GC) in the presence of trimethylsulfonium hydroxide, using a vertical microfurnace pyrolyzer, was validated for the compositional analysis of fatty acid components in microalgae. The chromatograms of a microalga Pavlova lutheri obtained under optimized THM conditions clearly showed a series of fatty acid methyl ...
Cohen Steven A - - 2012
The non-protein amino acid l-α-amino-β-methylaminopropionic acid (BMAA) has been linked to several neurodegenerative diseases. Its presence in trace amounts in complex sample such as bacterial, plant and mammalian tissue extracts and hydrolyzates makes analysis a complicated process requiring good analytical technique. There are conflicting reports in the literature regarding the ...
Corso Gaetano - - 2012
The use of Fourier transform infrared spectromicroscopy and mass spectrometry (MS) allowed us to characterize the composition of polar and non-polar binders present in sporadic wall paint fragments taken from Pompeii's archaeological excavation. The analyses of the polar and non-polar binder components extracted from paint powder layer showed the presence ...
Akkahat Piyaporn - - 2012
The immobilization of thiol-terminated poly[(methacrylic acid)-ran-(2-methacryloyloxyethyl phosphorylcholine)] (PMAMPC-SH) brushes on gold-coated surface plasmon resonance (SPR) chips was performed using the "grafting to" approach via self-assembly formation. The copolymer brushes provide both functionalizability and anti-fouling characteristics, desirable features mandatorily required for the development of an effective platform for probe immobilization in ...
Forst Mindy B - - 2012
Boronic esters and acids are potential intermediates in the manufacture of many active pharmaceutical ingredients (API). Accurate quantitation of the intermediate is necessary to assure the stoichiometry of the reaction. The analysis of these compounds is challenging due to their labile nature. For example, the boronic ester can hydrolyze to ...
Lee Seung Muk - - 2012
C-doped MgB2 wires were fabricated from a polyacrylic acid (PAA) using a conventional in-situ PIT technique. The effects of the PAA content on the lattice parameter, microstructure, critical temperature (Tc) and critical current density (Jc) were examined. With increasing PAA content, the amount of MgO in the sample increased but ...
Kim Ki Hyun - - 2012
A bioassay-guided fractionation and chemical investigation of a MeOH extract of the Korean wild mushroom Boletus pseudocalopus resulted in the identification of three new fatty acid esters, named calopusins A-C (1-3), along with two known fatty acid methyl esters (4-5). These new compounds are structurally unique fatty acid esters with ...
Vargas Leidy Johana - - 2012
Snake venoms are complex mixtures of proteins among which both basic and acidic phospholipases A(2) (PLA(2)s) can be found. Basic PLA(2)s are usually responsible for major toxic effects induced by snake venoms, while acidic PLA(2)s tend to have a lower toxicity. A novel PLA(2), here named PnPLA(2), was purified from ...
Perez-Estrada Salvador - - 2012
Abstract. Benzoyl-S,O-acetals 1a and 1b were used as chiral auxiliaries to achieve the diastereoselective preparation of both enantiomers of 2-methoxy-2-phenylpent-3-ynoic acids (MPPA). The latter were condensed with several chiral secondary alcohols and some primary amines to evaluate their potential as Chiral Derivatizing Agents (CDAs). The 1H NMR spectra of the ...
Sun Guangli - - 2012
Our ongoing investigations on the stem bark of Uncaria macrophylla afforded a new ursolic triterpene, 3β,6β,19α-trihydroxy-urs-12-en-28-oic acid-24-carboxylic acid methyl ester (1), named uncariursanic acid, and three known ursolic triterpenes including 3β,6β,19α-trihydroxy-23-oxo-urs-12-en-28-oic acid (2), 3β,6β,19α-trihydroxy-urs-12-en-28-oic acid (3) and ursolic acid (4). Their structures were elucidated by extensive spectral methods, including 1D ...
Hasheminia Seyed Mohsen - - 2012
The aim of this study was to compare the effect of 17% EDTA, 5% maleic acid, and Nd:YAG laser on smear layer removal by SEM. Eighty single-rooted teeth were divided into three groups of 25 according to the final procedure for smear layer removal: irrigation by 17% EDTA or 5% ...
Tian Li-Wen - - 2012
Three new phenolic compounds, eucalmaidin F (1), (3S)-5-guaiacyl-3-hydroxypentanoic acid (2), and 8-β-C-glucopyranosyl-5,7-dihydroxy-2-isobutylchromone (3), were isolated from the branches of E. maideni, together with 30 known compounds, including four phenylpropanoids, three lignans, four phloroglucinol glucosides, five dihydroflavonoids, seven simple phenolic compounds, six terpenoids, and glycerol. The new structures were established by spectroscopic ...
Cressman Erik N K - - 2012
Purpose: To investigate simultaneous and sequential injection thermochemical ablation in a porcine model, and compare them to sham and acid-only ablation. Materials and methods: This IACUC-approved study involved 11 pigs in an acute setting. Ultrasound was used to guide placement of a thermocouple probe and coaxial device designed for thermochemical ...
Suresh Challa - - 2012
Betulinic acid is a natural compound with high in vitro cytotoxicity toward many cancer cells. However, the poor water solubility of this compound hampers an effective in vivo cancer study. We prepared new ionic derivatives of betulinic acid with higher water solubilities, without losing the structural integrity and functionality of ...
Hegazy Gehan H - - 2011
Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently associated with gastric mucosal and renal adverse reactions, related to inhibition of cyclooxygenase1 (Cox1) in tissues where prostaglandins exert physiological effects. This led us to develop a set of ibuprofenic acid and mefenamic acid esters, namely: 4-((4-substituted benzylidene)amino)phenyl 2-(4-isobutylphenyl)propanoate and 4-((4-substituted benzylidene)amino)phenyl 2-((2,4-dimethylphenyl)amino)benzoate analogs, ...
Sun Yu-Wei - - 2011
Nine water-soluble chromone derivatives, including chromone-2-carboxylic acids, 2-methylchromones and their structural hybrids, were isolated from aerial tissues of Halenia elliptica (Gentianaceae), six of which were previously unknown. Their structures were elucidated by comprehensive mass, 1D and 2D NMR spectroscopic analyses and chemical derivatization. Two unstable structural hybrids of chromone-2-carboxylic acids ...
Xia Jia-Han - - 2011
Six previously unreported and 11 known terpenoids were isolated from Abies holophylla. The structures of the six compounds were established as two unusual bisabolane sesquiterpenoids, three nortriterpenoids, and one 3,4-seco-triterpenoid based on the detailed analysis of their 1D and 2D NMR spectroscopic data. In addition, electronic circular dichroism (ECD) calculations ...
Liu Jie-Qing - - 2011
A new pentanorlanostane, ganosineniol A ( 1), eight new lanostane triterpenoids, ganosinoside A ( 2), ganoderic acid Jc ( 3), ganoderic acid Jd ( 4), ganodermatetraol ( 5), ganolucidic acid γa ( 6), ganolucidate F ( 7), ganoderiol J ( 8), and methyl lucidenate Ha ( 9), and a new ...
Shichiri Mototada - - 2012
Chloroquine (CQ) is a widely prescribed anti-malarial agent and is also prescribed to treat autoimmune diseases. Clinical treatment with CQ is often accompanied by serious side effects such as hepatitis and retinopathy. As a weak base, CQ accumulates in intracellular acidic organelles, raises the pH, and induces osmotic swelling and ...
Woo Kyeong Wan - - 2011
A new lignan glycoside, named juniperigiside (1) was isolated from the CHCl(3) soluble fraction of the MeOH extract of stems and leaves of Juniperus rigida S.et Z. Compound 1 was identified by 1D- and 2D-NMR spectroscopy as well as CD analysis as (2R,3S)-2,3-dihydro-7-methoxy-2-(4'-hydroxy-3'-methoxyphenyl)-3-hydroxymethyl-5-benzofuranpropanol 4'-O-(3-O-methyl)-α-L-rhamnopyranoside. Five known lignans, icariside E4 (2), ...
Rodea-Palomares Ismael - - 2011
The combined toxicity of the perfluorinated surfactants perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and several pollutants (Hg(2+), Cd(2+), 2,4-D, propylparaben, mitomycin C and furazolidone) has been examined with a bioluminescent cyanobacterial toxicity test. Hg(2+), Cd(2+), mitomycin C and furazolidone could be included in the "Acute aquatic hazard" category established ...
García-Fernández L - - 2011
The antiangiogenic activity of different families of biocompatible and non-toxic polymer drugs based on 2-acrylamido-2-methylpropane sulfonic acid (AMPS) or polymethacrylic derivatives of 5-aminonaphthalen sulfonic acid (MANSA) is analyzed using directed in vivo angiogenesis assay and correlated with in vitro results. These active compounds were copolymerized with butylacrylate (BA) and N-vinylpyrrolidone ...
Kurata Shigeaki - - 2011
This study evaluated the cytotoxicity of various polybasic acids, poly(alkenoic acid)s, and the monomers with various acidic functional groups such as carboxyl, phosphoryl, and sulfo group. The cell growth of fibroblasts cultivated in medium containing polybasic acids and polymers up to the concentration to 5 mmol/L was not significantly different ...
Chandran Vineesh Indira - - 2011
We have previously reported a series of pH-sensitive imine-linked N-alkylisatin prodrugs that are stable at pH 7.4, but readily cleaved at pH 4.5. Herein, one of the most potent prodrugs, 5,7-dibromo-N-(p-methoxybenzyl)isatin (NAI), was functionalized with a para-phenylpropionic acid linker, and the resulting NAI-imine prodrug conjugated to transferrin (Tf) to form ...
Minehira Daisuke - - 2011
New substituted (1-thioxo-1,2,3,4-tetrahydro-β-carbolin-9-yl)acetic acids were designed as the inhibitor of AKR1B1 based upon the structure of rhetsinine, a minor alkaloidal component of Evodia rutaecarpa, and twenty derivatives were synthesized and evaluated. The most active compound of the series was (2-benzyl-6-methoxy-1-thioxo-1,2,3,4-tetrahydro-β-carbolin-9-yl)acetic acid (7m), which showed comparable inhibitory activity for AKR1B1 (IC(50)=0.15μM) ...
Antar-Shultz M - - 2011
Hydrofluoric acid (HF) is a highly toxic poison that can be rapidly fatal. Death usually results from the many systemic effects of dissociated fluoride ions, including hypocalcemia, hypomagnesemia, hyperkalemia, and direct cardiotoxicity. A patient is described who accidentally ingested a hydrofluoric acid-containing substance and who likely benefited from hemodialysis. His ...
Mulholland Dulcie A - - 2011
Four triterpenoids isolated from the leaves of Fadogia tetraquetra var. tetraquetra, 3beta-hydroxy-11alpha, 12alpha-epoxyoleanan-28,13beta-olide (1), 3beta-hydroxyurs-11-en-28,13beta-olide (2), oleanolic acid (3), and ursolic acid (4), were evaluated for their antiviral and antibacterial properties. Compound 4 showed potent activity against the Semliki Forest virus with an IC50 of 14.7 microM, but was also ...
Fang M J - - 2011
A new diphenyl ether methyl 2-(2-formyl-3-hydroxy-5-methylphenoxy)-5-hydroxy-3-methoxybenzoate (3), together with four known compounds, asterric acid (1), methyl asterrate (2), 9(Z),12(Z)-nonadecadienoic acid (4) and orsellinic acid (5), were isolated from the Phoma sp. strain SHZK-2, which was isolated from a polluted environment in southern China. The structures of these compounds were determined ...
Ramsay Kamdem Soup T - - 2011
Phytochemical investigation of the stem bark of Stereospermum acuminatissimum K. Schum. resulted in the isolation of 21 compounds, including two new guanine derivatives, 1,3,7-trimethylguanin-1/3-ium (1) and 3,7-dimethylguanin-1/3-ium (2), and one new phenolic long chain ester, 4-hydroxyphenethyl hentriacontanoate (3). The known compounds were identified as sterequinones A, F, and H (4, ...
Jones David D Petroleum and Environmental Geochemistry Group, Biogeochemistry Research Centre, University of Plymouth, Drake Circus, Plymouth PL4 8AA, United - - 2011
Numerous studies have suggested that the toxicity of organic compounds containing at least one carboxylic acid group and broadly classified as "naphthenic acids", is of environmental concern. For example, the acute toxicity of the more than 1 billion m(3) of oil sands process-affected water and the hormonal activity of some ...
Csuk René - - 2011
The extracts of the roots of licorice have been used in traditional and folk medicine to treat a broad variety of maladies. The main ingredient of these extracts is glycyrrhicinic acid. Its aglycon, glycyrrhetinic acid, has many biological activities, among them a pronounced cytotoxicity against tumor cells. In this study ...
Zeng Xiaobin - - 2011
This study investigated the antioxidant and cytotoxic activity of the phenolics isolated from the fruits of Livistona chinensis. Four new compounds, 1-{ω-isoferul[6- (4-hydroxybutyl)pentadecanoic acid]}-glycerol (1), E-[6'-(5″-hydroxypentyl)tricosyl]-4-hydroxy-3-methoxycinnamate (2), 2-(3'-hydroxy-5'-methoxyphenyl)-3-hydroxylmethyl-7-methoxy-2,3-dihydrobenzofuran-5- carboxylic acid (3), 7-hydroxy-5,4'-dimethoxy-2-arylbenzofuran (4), together with eleven known phenolics (5-15), were isolated and identified. Among these compounds, 1-4, 5-O-caffeoylshikimic acid (5), ...
Jinadasa R G Waruna - - 2011
A series of amino acid conjugates of chlorin e(6), containing lysine or aspartic acid residues in positions 17(3), 15(2), or 13(1) of the macrocycle were synthesized and investigated as photosensitizers for photodynamic therapy of tumors. All three regioisomers were synthesized in good yields and in five steps or less from ...
Chu Hunghao - - 2011
Polycations are very useful in biotechnology. However, most existing polycations have high toxicity that significantly limits their clinical translation. We designed poly(ethylene argininylaspartate diglyceride) (PEAD) that is based on arginine, aspartic acid, glycerol, and ethylene glycol. A set of in vitro assays demonstrated that PEAD exhibited no cytotoxicity at 1 ...
Dailey Oliver D OD - - 2011
A number of unsaturated fatty acids and a few saturated branched-chain fatty acids have been reported to exhibit anticancer activity. In previously reported research, several novel branched-chain derivatives (methyl, n-butyl, phenyl) of methyl oleate were produced by bromination in the allylic position and subsequent treatment with organocuprate reagents. These compounds ...
Shabana Marawan M - - 2011
The leaf ethanol extract of Harpephyllum caffrum Bernh. has evidenced medicinal value due to its hepatoprotective activity. It demonstrated inhibitory effects on test standard microbes approximated to 40% the potency of ofloxacin and fluconazole. The same extract evidenced in vitro cytotoxicity on human cell lines, liver carcinoma HEPG2, larynx carcinoma ...
Santra Santimukul - - 2011
The development of functional amino acid-based polymeric materials is emerging as a platform to create biodegradable and nontoxic nanomaterials for medical and biotechnology applications. In particular, facile synthetic routes for these polymers and their corresponding polymeric nanomaterials would have a positive impact in the development of novel biomaterials and nanoparticles. ...
Santra Santimukul - - 2011
Herein we describe the design and synthesis of a folate-doxorubicin conjugate with activatable fluorescence and activatable cytotoxicity. In this study we discovered that the cytotoxicity and fluorescence of doxorubicin are quenched (OFF) when covalently linked with folic acid. Most importantly, when the conjugate is designed with a disulfide bond linking ...
Boltes Karina - - 2011
The toxicological interaction of perfluorooctane sulphonic acid (PFOS) with the chlorinated pollutants triclosan and 2,4,6-trichlorophenol and the lipid regulators gemfibrozil and bezafibrate was evaluated using the combination index-isobologram equation. The endpoint for bioassays was the growth rate inhibition of the green alga Pseudokirchneriella subcapitata. The results showed that most of ...
Ohkura Naoki - - 2011
Pollen Typhae is the traditional Chinese herbal medicine widely used to treat the hemorrhagic diseases both by external and oral application. The present study examines the hemostatic properties and its components of Pollen Typhae. Pollen extract significantly reduced prothrombin time (PT), activated partial prothrombin time (APTT) and recalcification time. Pollen ...
Du Ying-Chi - - 2011
Antrodia camphorata (AC), also known as Antrodia cinnamomea, an endemic species in Taiwan, is one of the treasured medicinal mushrooms. AC is traditionally used for its chemopreventive biofunctions. In this investigation, we report a convenient method for concentrating the antiproliferative active triterpenoid-rich fraction (FEA), from ethanolic extract of AC (EEAC). ...
Arouri Ahmad - - 2011
A novel approach to anticancer drug delivery is presented based on lipid-like liposome-forming anticancer prodrugs that are susceptible to secretory phospholipase A(2) (sPLA(2)) that is overexpressed in several cancer types. The approach provides a selective unloading of anticancer drugs at the target tissues, as well as circumvents the necessity for ...
Kim Ki Hyun - - 2011
A bioassay-guided fractionation and chemical investigation of the trunk of BERBERIS KOREANA led to the isolation and identification of three new triterpenoids, 2 α,3 α,19 α-trihydroxy-urs-12-en-24-formyl-28-oic acid ( 1), 2 α,3 β,21 α-trihydroxy-urs-12-en-28-oic acid ( 2), and 3 β-acetyloxy-1-oxo-olean-12-en-28-oic acid ( 3), along with seven known triterpenoids ( 4- 10). ...
El-Askary Hesham I - - 2011
Ethanolic and aqueous extracts of the leaves and flowers of Alstonia scholaris were evaluated for their antioxidant activity by investigating their effect on blood glutathione levels in alloxan-induced diabetic rats. The ethanolic extract of the leaves was the most active; therefore, its cytotoxicity against HepG2 cells was also tested. Promising ...
Serini Simona - - 2011
There is some evidence to support the toxicity of polyunsaturated fatty acids (PUFAs) and their oxidative products, suggesting their involvement in the pathogenesis of different chronic diseases, including cancer. It has been shown that products of PUFA oxidation may exert a carcinogenic action by forming mutagenic adducts with DNA. On ...
Chen Zhu - - 2011
PURPOSE: Targeting to antigen-presenting cells and efficient intracellular delivery of pDNA are essential for development of microsphere formulations of DNA vaccine. METHODS: Biodegradable polymers containing acid-labile segments and galactose grafts were developed to entrap pDNA polyplexes into microspheres, which were proposed to promote transfection efficiency of pDNA. RESULTS: Acid-labile characteristics ...
Han Bingnan - - 2011
Two new cyclic depsipeptides wewakamide A (1) and guineamide G (2) have been isolated from the marine cyanobacterium Lyngbya semiplena and Lyngbya majuscula, respectively, collected from Papua New Guinea. The amino and hydroxy acid partial structures of wewakamide A and guineamide G were elucidated through extensive spectroscopic techniques, including HR-FABMS, ...
Kim Jeong Ah - - 2011
Three ent-kaurane diterpenes (1-3), four lupane-triterpene glycosides (4-7), and an oleanane-triterpene glycoside (8) were isolated from the ethyl acetate and water extracts of the steamed leaves of Acanthopanax koreanum using a combination of various column chromatographies. The structures of the isolates were determined by 1H-, 13C-NMR spectroscopy and mass spectrometry. ...
Csuk René - - 2011
Triterpenoic acids show many pharmacological effects, among them an antiinflammatory or an antitumor activity. One of these, glycyrrhetinic acid (1) is of interest because of its antitumor profile. Glycyrrhetinic acid is not only cytotoxic but also triggers apoptosis in various human tumor cell lines. To improve the cytotoxicity of parent ...
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