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Wu Jie - - 2012
Homoallylic carbamates bearing an α,β-unsaturated ester or an allylic carbonate were generated respectively utilizing novel chiral silanes through Lewis acid promoted asymmetric aminocrotylation. Those bifunctional building blocks could further undergo Michael addition or cyclization to selectively form functionalized lactams, azetidines, and tetrahydropyrimidinones.
Hoare Todd - - 2012
Nanogels based on poly(N-isopropylacrylamide) are attractive vehicles for prolonged duration local anesthesia because of their tunable size, number of functional groups, thermoresponsiveness and anionic charge. Nerve block durations of up to 9h were achieved using acrylic acid-loaded nanogels loaded with bupivacaine. Increasing the anionic charge density of the nanogels or ...
Fan Yi Chiao - - 2012
In this study we used sequential catalysis-PPh(3)--catalyzed nucleophilic addition followed by Pd(0)-catalyzed Heck cyclization--to construct complex functionalized alkylidene phthalans rapidly, in high yields, and with good stereoselectivities (E/Z ratios of up to 1:22). The scope of this Michael-Heck reaction includes substrates bearing various substituents around the alkylidene phthalan backbone. Applying ...
Nara T - - 2012
Circumanal glands are prominent features of the canine perianal skin, which are often located near to the sebaceous glands and apocrine glands. As the functional relevance of circumanal glands is yet unknown, we studied the localisation of sialic acids and anti-microbial substances (lysozyme, immunoglobulin A, lactoferrin, β-defensin) in these glandular ...
Anantharaj S - - 2012
A new dual ester-urethane melt condensation methodology for biological monomers-amino acids was developed to synthesize new classes of thermoplastic polymers under eco-friendly and solvent free polymerization approach. Naturally abundant L-amino acids were converted into dual functional ester-urethane monomers by tailor made synthetic approach. Direct polycondensation of these amino acid monomers ...
Eissa Ahmed M - - 2012
This article describes a versatile method for the modification of 2-hydroxyethyl cellulose (HEC) involving azide-alkyne cycloaddition reaction to impart neutral (ester) and ionic (carboxylic acid and 1(ry) amine) functionalities. The synthetic approach involved, first the introduction of the azide functionality to HEC and then followed by its cycloaddition reaction with ...
Zou Xiajuan - - 2012
In this study we describe a method for highly specific enrichment of glycopeptides with boronic acid-functionalized chitosan polymeric nanospheres and matrix assisted laser desorption-ionization mass spectrometry (MALDI-MS). This is the first time chitosan has been used to create nanosphere support material for selective enrichment of glycopeptides by modification with glycidyl ...
Qu Yanyan - - 2012
The boronic acid-functionalized core-shell polymer nanoparticles, poly(N,N-methylenebisacrylamide-co-methacrylic acid)@4-vinylphenylboronic acid (poly(MBA-co-MAA)@VPBA), were successfully synthesized for enriching glycosylated peptides. Such nanoparticles were composed of a hydrophilic polymer core prepared by distillation precipitation polymerization (DPP) and a boronic acid-functionalized shell designed for capturing glycopeptides. Owing to the relatively large amount of residual vinyl ...
Pinheiro Vitor B VB Laboratory of Molecular Biology, Medical Research Council, Cambridge CB2 0QH, - - 2012
Life's diversity is built on the wide range of properties and functions that can be encoded in natural biopolymers such as polypeptides and nucleic acids. However, despite their versatility, the range of chemical functionalities is limited, particularly in the case of nucleic acids. Chemical modification of nucleic acids can greatly ...
Jansen Janine - - 2012
Photo-crosslinked networks were prepared from fumaric acid monoethyl ester-functionalized poly(D,L-lactic acid) oligomers and N-vinyl-2-pyrrolidone. Two model proteins, lysozyme and albumin, were incorporated into the network films as solid particles and their release behavior was studied. By varying the NVP content and macromer molecular weight, degradation behavior and protein release profiles ...
Möller Heinz - - 2012
A new sialic acid in the house! A biosynthetic approach gives access to previously inaccessible C7 modifications of sialic acids in living cells. Metabolic incorporation of synthetically derived N-acetyl-4-azido-4-deoxymannosamine into glycans of mammalian cells and zebrafish larvae preserves the bioorthogonal functionality of its azido group for subsequent labeling with biophysical ...
Fernstrom John D - - 2012
The ingestion of large neutral amino acids (LNAA), notably tryptophan, tyrosine and the branched-chain amino acids (BCAA), modifies tryptophan and tyrosine uptake into brain and their conversion to serotonin and catecholamines, respectively. The particular effect reflects the competitive nature of the transporter for LNAA at the blood-brain barrier. For example, ...
Anbarasu Anand - - 2012
To understand the role of FYN (Fibroblast Yes related novel) gene products in relation to neurodegeneration and Alzheimer's disease we have analyzed the SNPs (single nucleotide polymorphism) associated with this gene. This can help us to understand the genetic variations that can alter the function of the gene products. A ...
van de Rest Ondine - - 2012
Background: Nutrition is one of many factors that affect brain development and functioning, and in recent years the role of certain nutrients has been investigated. B vitamins and n-3 polyunsaturated fatty acids (PUFA) are two of the most promising and widely studied nutritional factors. Methods: In this review, we provide ...
Venkata Mohan S - - 2012
Functional behavior of anoxic-aerobic-anoxic microenvironment on azo dye (C.I. Acid black 10B) degradation was evaluated in a periodic discontinuous batch mode operation for 26 cycles. Dye removal efficiency and azo-reductase activity (30.50±1U) increased with each feeding event until 13th cycle and further stabilized. Dehydrogenase activity also increased gradually and stabilized ...
Khalimon Andrey Y - - 2012
A molecule that releases the strong organometallic Lewis acid B(C6F5)3 upon irradiation with 254 nm light has been developed. This photo Lewis acid generator, or "PhLAG" now enables the photocontrolled initiation of several reactions catalyzed by this important Lewis acid. Herein is described the synthesis of the triphenylsulfonium salt of ...
Fischer Marco - - 2012
The model actinobacterium Streptomyces coelicolor A3(2) uses nitrate and sulfate as nitrogen and sulfur sources, respectively. The final step prior to assimilation into amino acids is the six-electron reduction of the nitrite and sulfite anions, catalyzed by siroheme-dependent nitrite (NirBD) and sulfite (SirA) reductases. There are two predicted nitrite/sulfite reductases ...
Hager Anna-Sophie - - 2012
Vital wheat gluten, a by-product of wheat starch production, is a highly functional ingredient and its unique viscoelasticity make it ideal for the production of edible biodegradable films. However, its functional properties must be modified to ensure sufficient strength and elasticity, as well as water vapour barrier properties. In this ...
García-López José-Antonio - - 2012
Reaction of ortho-palladated derivatives of phentermine and homoveratrylamine with benzyne allows the synthesis of enlarged eight-membered palladacycles resulting from the insertion of the aryne into the Pd-C bond, which subsequently react with CO, to render unnatural amino acid derivatives.
Yu Fang - - 2012
Catharanthus roseus accumulates high levels of the pentacyclic triterpene, ursolic acid, as a component of its wax exudate on the leaf surface. Bioinformatic analyses of transcripts derived from the leaf epidermis provide evidence for the specialized role of this tissue in the biosynthesis of ursolic acid. Cloning and functional expression ...
Han Ruizhi - - 2012
Vitamin C (VC) is an essential nutrient that cannot be synthesized by the human body. Due to its extreme instability, various VC derivatives have been developed in an attempt to improve stability while retaining the same biological activity. One of the most important VC derivatives, 2-O-D: -glucopyranosyl-L: -ascorbic acid (AA-2G), ...
Chen Mingxun - - 2012
Previous studies based on microarray analysis have found that DELLAs downregulate several GDSL genes in unopened flowers and/or imbibed seeds. This suggests the role of DELLAs in seed fatty acid (FA) metabolism. In the present study, enhancement of GA signaling through DELLA mutation or exogenous GA(3) resulted in the upregulated ...
Nagano Minoru - - 2012
2-Hydroxy fatty acids (2-HFAs) are predominantly present in sphingolipids and have important physicochemical and physiological functions in eukaryotic cells. Recent studies from our group demonstrated that sphingolipid fatty acid 2-hydroxylase (FAH) is required for the function of Arabidopsis (Arabidopsis thaliana) Bax inhibitor-1 (AtBI-1), which is an endoplasmic reticulum membrane-localized cell ...
Ye Yingda - - 2012
This communication describes the development of a mild method for the cross-coupling of arylboronic acids with CF(3)I via the merger of photoredox and Cu catalysis. This method has been applied to the trifluoromethylation of electronically diverse aromatic and heteroaromatic substrates and tolerates many common functional groups.
Almaida-Pagán Pedro F - - 2012
Membrane composition, particularly of mitochondria, could be a critical factor by determining the propagation of reactions involved in mitochondrial function during periods of high oxidative stress such as rapid growth and aging. Considering that phospholipids not only contribute to the structural and physical properties of biological membranes, but also participate ...
Park Woo Jung - - 2012
The fatty acid desaturase (FADS) genes code for the rate-limiting enzymes required for the biosynthesis of long-chain polyunsaturated fatty acids (LCPUFA). Here we report discovery and function of a novel FADS1 splice variant. FADS1 alternative transcript 1 (FADS1AT1) enhances desaturation of FADS2, leading to increased production of eicosanoid precursors, the ...
Ojeda M L - - 2012
AIMS: The principal aim of this study was to investigate the oxidative effects of chronic ethanol consumption on the functions of the heart and the kidney and the possible modification of this effect by folic acid supplementation. Moreover, in order to find whether this oxidative profile affects cardiovascular function, parameters ...
Kawai Misako - - 2012
Amino acids are known to elicit complex taste, but most human psychophysical studies on the taste of amino acids have focused on a single basic taste, such as umami (savory) taste, sweetness, or bitterness. In this study, we addressed the potential relationship between the structure and the taste properties of ...
Yang Chia-Ying - - 2012
Mitochondria, once viewed as functioning relatively autonomously in the cell, have increasingly been recognized to be involved in numerous signaling networks that impact on a wide range of cell biological processes. In addition to the many types of proteins that mediate these pathways, the importance of signaling functions regulated via ...
Smesny Stefan S Department of Psychiatry, Jena University Hospital, Jena, Germany. - - 2013
There is considerable evidence for specific pathology of lipid metabolism in schizophrenia, affecting polyunsaturated fatty acids and in particular sphingolipids. These deficits are assumed to interfere with neuronal membrane functioning and the development and maintenance of myelin sheaths. Recent studies suggest that some of these lipid pathologies might also be ...
Cade W Todd WT Program in Physical Therapy & Department of Medicine, Washington University School of Medicine, Box 8502, St Louis, MO 63108, USA. - - 2013
Barth syndrome (BTHS) is a rare X-linked disorder that is characterized by mitochondrial abnormalities, infantile or childhood onset of cardioskeletal myopathy, and high mortality rates. It is currently unknown if BTHS related mitochondrial dysfunction results in substrate metabolism abnormalities and thereby contributes to cardioskeletal myopathy in patients with BTHS. Adolescents ...
Chen Xin - - 2012
Reflux of acid and bile acids contributes to epithelial tissue injury in gastro-esophageal reflux disease. However, the influence of refluxed material on human esophageal stratified epithelial barrier function and tight junction (TJ) proteins has not been fully elucidated. Here, we investigated the influence of acid and bile acids on barrier ...
Fonseca Andrea S C - - 2012
A novel fluorescent amino acid, L: -4-chloromethylcoumarin-6-yl-alanine, was obtained from tyrosine by a Pechmann reaction. The assembly of the heterocyclic ring at the tyrosine side chain could be achieved before or after incorporation of tyrosine into a dipeptide, and amino acid and dipeptide ester conjugates were obtained by coupling to ...
Hung Chuan-Chuan - - 2012
BACKGROUND: β-amino acids play important biological roles as precursors in the biosynthesis of antibiotics, anticancer agents, neurotransmitters, and other high molecular weight polymers. Microbial cells and enzymes from extreme environments offer new opportunities for biocatalysis and biotransformations as a result of their extreme stability. Lysine 2,3-aminomutase catalyzes the interconversion of ...
Karacali Bilge - - 2012
We propose hierarchical motif vectors to represent local amino acid sequence configurations for predicting the functional attributes of amino acid sites on a global scale in a quasi-supervised learning framework. The motif vectors are constructed via wavelet decomposition on the variations of physico-chemical amino acid properties along the sequences. We ...
Zäuner Simone - - 2012
Monogalactosyldiacylglycerol (MGDG) in Chlamydomonas reinhardtii and other green algae contains hexadeca-4,7,10,13-tetraenoic acid (16:4) in the glycerol sn-2 position. While many genes necessary for the introduction of acyl chain double bonds have been functionally characterized, the Δ4-desaturase remained unknown. Using a phylogenetic comparison, a candidate gene encoding the MGDG-specific Δ4-desaturase from ...
Arsenault Dany - - 2012
Dietary lipids modify brain fatty acid profile, but evidence of their direct effect on neuronal function is sparse. The enthorinal cortex (EC) neurons connecting to the hippocampus play a critical role in learning and memory. Here, we have exposed mice to diets based on canola:soybean oils (40:10, g/kg) or safflower:corn ...
Kumari Manju M Institute of Molecular Biosciences, University of Graz, Graz, - - 2012
Numerous studies in humans link a nonsynonymous genetic polymorphism (I148M) in adiponutrin (ADPN) to various forms of fatty liver disease and liver cirrhosis. Despite its high clinical relevance, the molecular function of ADPN and the mechanism by which I148M variant affects hepatic metabolism are unclear. Here we show that ADPN ...
Stevens Tyler - - 2012
Oxidative stress is intimately involved in the pathogenesis of chronic pancreatitis (CP), and its quantification may represent a useful biomarker. The aim was to determine whether oxidized fatty acid (OxFA) levels in serum and/or pancreatic fluid are elevated in CP. Patients evaluated for abdominal pain were classified into 3 groups ...
Hsu C-C - - 2012
The Pringle maneuver is a surgical procedure to minimize hemorrhage during hepatectomy, which however, can induce production of reactive oxygen species causing remote organ injury. We sought to study the impact of the Pringle maneuver on cardiac function as well as the protective effects of L-ascorbic acid and α-tocopherol pretreatments. ...
Sprenger Norbert - - 2012
Early postnatal development encounters milk as a key environmental variable and yet the sole nutrient source. One evolutionary conserved constituent of milk is sialic acid, which is generally displayed on glycoconjugates and free glycans. During early postnatal development, high sialic acid need was proposed to be unmet by the endogenous ...
Vogt Andrew P - - 2012
Boronic acid-functionalized microspheres are prepared for the first time via mild epoxide ring opening based on porous cross-linked polymeric microspheres (diameter ≈ 10 μm, porosity ≈ 1000 Å). Quantitative chemical analysis by XPS and EA evidences that there is a greater functionalization with boronic acid when employing a sequential synthetic ...
Elstner Martin - - 2012
In this communication we describe a two-component saccharide probe with logic capability. The combination of a boronic acid-appended viologen and perylene diimide was able to perform a complementary implication / notimplication logic function. Fluorescence quenching and recovery with fructose was analyzed with fluorescence correlation spectroscopy on few molecule level of ...
Keith John A - - 2012
The role of pyridinium cations in electrochemistry has been believed known for decades, and their radical forms have been proposed as key intermediates in modern photoelectrocatalytic CO(2) reduction processes. Using first-principles density functional theory and continuum solvation models, we have calculated acidity constants for pyridinium cations and their corresponding pyridinyl ...
Pérez-Labrada Karell - - 2012
Unique types of ceramide and glycolipid architectures were obtained by means of Ugi reactions incorporating lipidic isocyanides as surrogates of sphingolipids. The multicomponent nature of this process allowed for a highly efficient assembly process, wherein two of the components provided the lipidic tails while a third one incorporated either the ...
Sim Adelene Y L AY Department of Applied Physics, Stanford University, Stanford, CA 94305, - - 2012
Nucleic acids are an important class of biological macromolecules that carry out a variety of cellular roles. For many functions, naturally occurring DNA and RNA molecules need to fold into precise three-dimensional structures. Due to their self-assembling characteristics, nucleic acids have also been widely studied in the field of nanotechnology, ...
Stiburkova Blanka - - 2012
Renal hypouricaemia is a heterogeneous inherited disorder characterized by impaired tubular uric acid transport with severe complications, such as acute kidney injury and nephrolithiasis. Type 1 is caused by a loss-of-function mutation in the SLC22A12 gene (OMIM #220150), while type 2 is caused by defects in the SLC2A9 gene (OMIM ...
Gurinov Andrey A - - 2012
Solvation at the interphase: A study of the influence of water on the effective acidity of silanol and carboxylic acid groups of propionic acid functionalized SBA-15 reveals that to affect the proton-donating ability of an acidic group at the surface, water should be able to form a solvation shell around ...
Guo Lin - - 2012
FA 2-hydroxylase (FA2H) is an NAD(P)H-dependent enzyme that initiates FA α oxidation and is also responsible for the biosynthesis of 2-hydroxy FA (2-OH FA)-containing sphingolipids in mammalian cells. The 2-OH FA is chiral due to the asymmetric carbon bearing the hydroxyl group. Our current study performed stereochemistry investigation and showed ...
Brosnan John T - - 2012
Glutamate is one of the most abundant of the amino acids. In addition to its role in protein structure, it plays critical roles in nutrition, metabolism and signaling. Post-translational carboxylation of glutamyl residues increases their affinity for calcium and plays a major role in hemostasis. Glutamate is of fundamental importance ...
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