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Hoang Cam Thuy - - 2009
A general strategy for the amino acid homologation via Blaise reaction and subsequent reduction is presented. This strategy involves the preparation of protected alpha-amino nitriles from the corresponding amino acids, followed by the zinc-mediated condensation of tert-butyl bromoacetate, to give the imidazolidones after iminozincate cyclization. Reduction gave the saturated imidazolidinones ...
Koide Tetsuya - - 2009
In fish, amino acids are food-related important olfactory cues to elicit an attractive response. However, the neural circuit underlying this olfactory behavior is not fully elucidated. In the present study, we applied the Tol2 transposon-mediated gene trap method to dissect the zebrafish olfactory system genetically. Four zebrafish lines (SAGFF27A, SAGFF91B, ...
Fujioka Kouki - - 2009
Mars is a CO(2)-abundant planet, whereas early Earth is thought to be also CO(2)-abundant. In addition, water was also discovered on Mars in 2008. From the facts and theory, we assumed that soda fountains were present on both planets, and this affected amino acid synthesis. Here, using a supercritical CO(2)/liquid ...
Gupta Nishkarsh - - 2009
Hypothermia is a common occurrence under anaesthesia and may prolong the duration of action of neuromuscular blockade. By limiting fall in temperature, an infusion of amino acid enriched solution may speed the recovery from neuromuscular blockade. We studied 60 ASA Grade - I/II patients of aged between 20 to 60 ...
Liang Chao - - 2009
The amino sugars (e.g., glucosamine, galactosamine, mannosamine, muramic acid) in soils are frequently employed as biomarkers of microbial residues. The analysis of amino sugars in environmental matrices, however, is expected to be more complicated than their determination in isolated microbial cells. In this study, we employed a widely used protocol ...
Mejia Alex - - 2009
Acid peptic disorders are the result of distinctive, but overlapping pathogenic mechanisms leading to either excessive acid secretion or diminished mucosal defense. They are common entities present in daily clinical practice that, owing to their chronicity, represent a significant cost to healthcare. Key elements in the success of controlling these ...
Adedokun S A - - 2009
1. This study determined the effect of bird type (broilers, laying hens, or caecectomised roosters) on amino acid digestibility of feedstuffs from 5 plant sources and one animal source. 2. The standardised amino acid digestibility (SAAD) were obtained by correcting apparent ileal amino acid digestibility (AIAAD) values for basal ileal ...
Sieg Anke - - 2009
Reverse iontophoresis across the skin is a potentially useful alternative for non-invasive clinical and therapeutic drug monitoring. In this work, the reverse iontophoretic extraction of 17 amino acids was studied in vivo in healthy volunteers. Charged amino acids were primarily extracted towards the electrode of opposite polarity, while zwitterionic species ...
Jover Jesús - - 2009
The quantitative structure-property relationship (QSPR) methodology is applied to estimate the binding affinity of lithium, sodium, potassium, copper, and silver cations to the 20 common amino acids. The proposed model, nonlinearly derived from computational neural networks (CNN), contains seven descriptors and was validated by an external prediction set. Good results ...
Yang Gang - - 2009
Density functional calculations were employed to stabilize multi-amino acid zwitterions by metal ions as well as to understand the stabilizing mechanism. This work distinguishes from the previous metalations and stabilizations of a single amino acid zwitterion, where the metal ions are coordination-unsaturated. It was found that up to three Gly ...
Liebert F - - 2009
Data analysis utilized four growth experiments with mixed diets limiting in lysine, in threonine, and in methionine respectively. All male juvenile Orechromis niloticus [12 g average body weight instead of average (BW) at start, four repetition tanks per diet, 56 days experimental period] provided the database for application of an ...
Rajesh Chinagandham - - 2009
In this study we have investigated the interaction of phenylalanine (Phe), histidine (His), tyrosine (Tyr), and tryptophan (Tryp) molecules with graphene and single walled carbon nanotubes (CNTs) with an aim to understand the effect of curvature on the non-covalent interaction. The calculations are performed using density functional theory and the ...
Glavin Daniel P - - 2009
The distribution and enantiomeric composition of the 5-carbon (C(5)) amino acids found in CI-, CM-, and CR-type carbonaceous meteorites were investigated by using liquid chromatography fluorescence detection/TOF-MS coupled with o-phthaldialdehyde/N-acetyl-L-cysteine derivatization. A large L-enantiomeric excess (ee) of the alpha-methyl amino acid isovaline was found in the CM meteorite Murchison (L(ee) ...
Heyda Jan - - 2009
Ion specific behavior of halides at surfaces of aqueous basic amino acids is unraveled by means of molecular dynamics simulations employing both nonpolarizable and polarizable force fields. Analysis in terms of density plots, cumulative sums, and residence times provides a clear, robust, and quantitative picture of specific ion effects. Small ...
Tachibana Shinjiro - - 2009
Replacement of glycine by serine at positions 123 and 124 of phenylalanine dehydrogenases from Bacillus badius and Bacillus sphaericus respectively strikingly decreased enzyme activity toward aromatic amino acids and resulted in an elevation of relative activity toward aliphatic amino acids. The mutant from B. badius preferentially dehydrogenated branched-chain amino acids, ...
Hong Gongyi - - 2009
In examining adsorption of a few selected single amino acids on Au and Pd cluster models by density functional theory calculations, we have shown that specific side-chain binding affinity to the surface may occur because of a combination of effects, including charge transfer. Larger binding was calculated at the Pd ...
Koonin Eugene V - - 2009
The expansion of the standard code according to the coevolution theory. Phase 1 amino acids are orange, and phase 2 amino acids are green. The numbers show the order of amino acid appearance in the code according to (99). The arrows define 13 precursor-product pairs of amino acids, their color ...
Elango Rajavel - - 2009
Due to advances made in the development of stable isotope based carbon oxidation methods, the determination of amino acid requirements in humans has been an active area of research for the past 2 decades. The indicator amino acid oxidation (IAAO) method developed in our laboratory for humans has been systematically ...
Warwick Stuart - - 2009
Nuptial gifts that are manufactured by the male are found in numerous insect species and some spiders, but there have been very few studies of the composition of such gifts. If, as has been proposed recently, nuptial gifts represent sensory traps, males will be selected to produce gifts that are ...
Di Giulio Massimo - - 2009
By generating random codes and applying Fisher's exact test, we confirm that the biosynthetic families of amino acids are intimately involved in the organisation of the genetic code. This observation corroborates the coevolution theory of genetic code origin. As the amino acids belonging to the single biosynthetic families have codons ...
Sieg Anke - - 2009
Reverse iontophoresis across the skin is a potentially useful alternative for non-invasive clinical and therapeutic drug monitoring. In this work, the reverse iontophoretic extraction of 17 amino acids was studied in vivo in healthy volunteers. Charged amino acids were primarily extracted towards the electrode of opposite polarity, while zwitterionic species ...
Turanov Anton A AA Department of Biochemistry and Redox Biology Center, University of Nebraska, Lincoln, NE 68588, - - 2009
Strict one-to-one correspondence between codons and amino acids is thought to be an essential feature of the genetic code. However, we report that one codon can code for two different amino acids with the choice of the inserted amino acid determined by a specific 3' untranslated region structure and location ...
Kimura Takeshi - - 2009
PURPOSE OF REVIEW: To highlight the usefulness of amino acid profiling in clinical diagnosis and current developments in analysis revealing underlying metabolic relationships. RECENT FINDINGS: Recent innovations in metabolomics and systems biology enable high throughput measurement of diverse amino acids and the subsequent data mining for various uses. Recent studies ...
Chen Xiangtao - - 2009
The aim of this research is to establish a new kind of simple and rapid method to determine amino acids and metal elements in Citrus reticulata Blanco cv. Ougan fruit. The high-performance liquid chromatography pre-column derivation method was used to test the contents of amino acids found in the cv. ...
Bamoharram Fatemeh F - - 2009
A study of the effects of the interactions with amino acids on the vibrational spectra of Keggin heteropolyanions (Na(n)H(3-)n[XM(12)O(40)](n-); n = 0,1,2,3; X = P(V), Si(IV), M = W(VI), Mo(VI)) has been performed. Interactions occurred for all of the studied compounds leading to changes and splits in the stretching frequencies. ...
Kim Eunjung - - 2009
Amino acids are fundamental nutrients for protein synthesis and cell growth (increase in cell size). Recently, many compelling evidences have shown that the level of amino acids is sensed by extra- or intra-cellular amino acids sensor(s) and regulates protein synthesis/degradation. Mammalian target of rapamycin complex 1 (mTORC1) is placed in ...
Cruz Fernando - - 2009
The expansion of amino acid repeats is determined by a high mutation rate and can be increased or limited by selection. It has been suggested that recent expansions could be associated with the potential of adaptation to new environments. In this work, we quantify the strength of this association, as ...
Dalby Andrew R - - 2009
Microsatellites have been used extensively in the field of comparative genomics. By studying microsatellites in coding regions we have a simple model of how genotypic changes undergo selection as they are directly expressed in the phenotype as altered proteins. The simplest of these tandem repeats in coding regions are the ...
Higgs Paul G - - 2009
The arrangement of the amino acids in the genetic code is such that neighbouring codons are assigned to amino acids with similar physical properties. Hence, the effects of translational error are minimized with respect to randomly reshuffled codes. Further inspection reveals that it is amino acids in the same column ...
Huelsenbeck John P JP Department of Integrative Biology, University of California, Berkeley, 3060 VLSB #3140, Berkeley, CA 94720-3140, USA. - - 2008
Models of amino acid substitution present challenges beyond those often faced with the analysis of DNA sequences. The alignments of amino acid sequences are often small, whereas the number of parameters to be estimated is potentially large when compared with the number of free parameters for nucleotide substitution models. Most ...
Tesseraud Sophie - - 2009
Protein synthesis is affected when an insufficient level of sulfur amino acids is available. This defect may originate from dietary amino acid deficiency and/or excessive amino acid utilisation for other purposes such as the synthesis of glutathione and acute-phase proteins during catabolic stress. Sulfur amino acids are recognised to exert ...
Wang Zuguang - - 2009
An aberrant WNT signaling contributes to the development and progression of multiple cancers. WNT5a is one of the WNT signaling molecules. This study was designed to test the hypothesis that amino acid deprivation induces changes in the WNT signaling pathway in colon cancer cells. Results showed that targets of the ...
Adedokun S A - - 2008
The standardized ileal amino acid digestibility (SIAAD) of 5 plant-based ingredients was determined in 5- and 21-d-old broiler chicks and turkey poults. Two diets (N-free diet, NFD, and a highly digestible protein diet 10% casein, HDP) were fed to determine ileal endogenous amino acid flow, and each was used for ...
McConathy Jonathan - - 2008
Amino acids are required nutrients for proliferating tumor cells, and amino acid transport is upregulated in many tumor types. Studies of radiolabeled amino acids in animals and humans demonstrate that amino acid based tracers have advantageous characteristics relative to 2-[(18)F]fluoro-2-deoxyglucose in certain tumors, particularly brain gliomas. Non-natural amino acids for ...
De Luca Vincenzo - - 2008
Abnormal levels of amino acids have been reported in patients with schizophrenia and have also been investigated as a biomarker to monitor antipsychotic treatment, however results have been inconsistent. The purpose of the present review is to summarize the evidence in the literature of whether amino acid levels can be ...
Palii S S - - 2009
Amino acid deprivation activates the amino acid response (AAR) pathway that enhances transcription of genes containing an amino acid response element (AARE). The present data reveal a quantitative difference in the response to deprivation of individual amino acids. The AAR leads to increased eukaryotic initiation factor 2alpha (eIF2alpha) phosphorylation and ...
Dioguardi Francesco Saverio - - 2008
The skin is an important organ, and the need for attention to its metabolic requirements is often underestimated by professionals involved with its integrity and beauty. Amino acids are the indispensable nutritional basis for the maintenance of its integrity. The skin has very peculiar amino acid needs, which should be ...
Selvaraju K - - 2009
Methyl-para-hydroxy benzoate is a potential organic nonlinear optical (NLO) material. The pure and amino acid (glycine) doped MHB crystals are grown by slow evaporation solution growth technique. Single crystal X-ray diffraction studies of both pure and amino acid doped samples are carried out and the results are compared. FTIR studies ...
Viedma Cristobal - - 2008
The inexorable evolution of solid-phase single chirality is demonstrated for the first time for a proteinogenic amino acid. Enantioenrichment is observed both under attrition-enhanced conditions and without the aid of particle grinding. Differences in the form of the conversion profiles for the process under the two sets of conditions provide ...
Zaia Dimas A M - - 2008
The adsorption of amino acids on minerals and their condensation under conditions that resemble those of prebiotic earth is a well studied subject. However, which amino acids should be used in these experiments is still an open question. The main goal of this review is to attempt to answer this ...
Ishihara Junko - - 2009
The objective of the present study was to evaluate the validity of a FFQ in the estimation of dietary amino acid intake. Amino acid intake was calculated using a composition database developed based on the Standard Tables of Food Composition for amino acids in Japan. Subjects were subsampled from two ...
Sturmey Roger G - - 2009
BACKGROUND: Embryos with greater viability have a lower or 'quieter' amino acid metabolism than those which arrest. We have hypothesized this is due to non-viable embryos possessing greater cellular/molecular damage and consuming more nutrients, such as amino acids for repair processes. We have tested this proposition by measuring physical damage ...
Sturmey Roger G - - 2008
This review assesses the ability of non-invasive 'amino acid profiling' to predict early embryo viability. The history of amino acid supplementation of embryo culture media and the role of amino acids in early embryo development are first considered and these are followed by a review of methods to quantify amino ...
Young Douglas D - - 2008
Microwave irradiation has been proven to be a useful tool in the rapid assembly of racemic unnatural amino acids in only two steps. Additional benefits of this methodology are the commercial availability of the inexpensive starting materials and the high yields and high purities of the final amino acid products.
Park Jin Hwan - - 2008
Microorganisms capable of efficient production of amino acids have traditionally been developed by random mutation and selection method, which might cause unwanted physiological changes in cellular metabolism. Rational genome-wide metabolic engineering based on systems and synthetic biology tools, which is termed 'systems metabolic engineering', is rising as an alternative to ...
Li Peng - - 2009
Recent evidence shows that some amino acids and their metabolites are important regulators of key metabolic pathways that are necessary for maintenance, growth, feed intake, nutrient utilization, immunity, behavior, larval metamorphosis, reproduction, as well as resistance to environmental stressors and pathogenic organisms in various fishes. Therefore, conventional definitions on essential ...
Hong H C - - 2009
Twenty amino acids were chlorinated and examined for the formation of trihalomethane (THM) and haloacetic acid (HAA). The amino acids exhibited a high Cl(2) demand (3.4-10 mg Cl(2) mg(-1) C) but low THM formation (<4.19 microg mg(-1) C) except for tryptophan and tyrosine (45.8 - 147 microg mg(-1) C). Large ...
Molleman Freerk - - 2008
1. In tropical forests, the adults of many butterfly species feed on fruits rather than nectar from flowers and have long life spans. Rotting fruit and nectar differ from each other in many respects, including sources of amino acids and microbial life. If amino acids in the adult diet can ...
Deval Christiane - - 2008
There is a growing body of evidence that suggests that amino acids play an important role in controlling gene expression, but the cell specificity of the amino-acid-mediated regulation of gene expression in mammals remains unknown. Using a model of muscle cells (C2C12) at two stages of differentiation, i.e. myoblasts and ...
Sieg Anke - - 2008
Reverse iontophoresis across the skin has been investigated as alternative, non-invasive method for clinical and therapeutic drug monitoring. This research investigated the reverse iontophoretic extraction of 19 amino acids present at clinically relevant levels in the subdermal compartment of an in vitro diffusion cell. Over a simulated, systemic concentration range ...
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