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Fürst Peter - - 2004
The aims of this introductory article are to survey and critically evaluate the concepts and approaches that have been used to assess amino acid adequacy and to hypothesize about possible future directions of research. The issue in question is extensive, consequently this article will be limited to: 1) definitions of ...
Caldwell John - - 2004
There have been major developments in our understanding of the ways in which genetic variation among individuals in a population can affect responses to drugs, and use of such information can improve the safety and efficacy of medicines. The brief review summarizes the emergence of modern pharmacogenetics, illustrating the importance ...
Pencharz Paul B - - 2004
Few data exist on amino acid needs in infants and children, mainly because until recently, amino acid requirements were determined using nitrogen balance. The advent of the indicator amino acid oxidation (IAAO) method permits studies to be conducted with minimal adaptation to the test amino acid. In light of the ...
Garlick Peter J - - 2004
In recent years there has been a large increase in the consumption of individual amino acids as dietary supplements. This has resulted not only from the use of certain amino acids as flavoring agents, but other amino acids are taken for perceived health benefit, for enhancement of physical performance, as ...
You Shu-Li - - 2004
A highly efficient enantiospecific synthesis of imidazoline-based amino acids is reported from dipeptides composed of a C-terminal beta-amino-alpha-amino acid residue using bis(triphenyl) oxodiphosphonium trifluoromethanesulfonate. These imidazolines were easily converted to imidazoles and incorporated into macrolactam analogues of bistratamide H without loss of stereochemical integrity.
Struck Christine - - 2004
SUMMARY The obligately biotrophic rust fungi are dependent on nutrient supply from their host plants. A cDNA library of infection structures of the rust fungus Uromyces fabae was used to identify a gene (UfAAT3) that encodes a protein with a high degree of sequence similarity to fungal amino acid permeases. ...
Talbi S - - 2004
To better understand the composite character of amino acids EPR spectra, the radiolysis and reactions which occurred after irradiation of amino acids, a comparative EPR study of a few simple amino acids has been made in order to identify qualitatively and quantitatively the different radiation-induced radicals in amino acid powders. ...
Swarna M - - 2004
A screening program was carried out for amino acid disorders in children with mental handicaps from the state of Andhra Pradesh (India) during the last two decades. Forty-one (0.9%) cases were detected with amino acid disorders among 4500 children surveyed. We reported amino acid disorders of rare occurrence such as ...
Tiwari F - - 2004
Adult Lymnaea acuminata (average length 20-22 mm) were collected locally from lakes and low-lying submerged fields from Gorakhpur. The chemoattraction studies were made in round glass aquaria measuring 30 cm in diameter and filled to a depth of 10 mm with 500 ml dechlorinated tap water. Each aquarium was divided ...
Silva Branca M - - 2004
Twenty-one free amino acids present in several samples of quince fruit (pulp and peel) and quince jam (homemade and industrially manufactured) were analyzed by GC/FID. The analyses showed some differences between quince pulps and peels. Generally, the highest content in total free amino acids and in glycine was found in ...
Yao Nian-Huan - - 2004
Direct O-glycosylation of amino acids bound to TentaGel resin with a number of glycosyl trichloroacetimidate donors results in high yields. The glycosylation reaction can be easily monitored by analyzing the bead-bound amino acids with high-resolution magic angle spinning (HR-MAS) NMR. These studies pave a new way for the construction of ...
Nakajima Yasufumi - - 2004
Administration of protein or amino acids enhances thermogenesis, presumably by stimulating oxidative metabolism. However, hyperthermia results even when thermoregulatory responses are intact, suggesting that amino acids also alter central thermoregulatory control. Therefore, the authors tested the hypothesis that amino acid infusion increases the thermoregulatory set point. Nine male volunteers each ...
Fontaine Johannes - - 2004
Four international ring trials for NIRS amino acid analysis of feed raw materials have demonstrated for the first time that the calibrations developed by Degussa allow reliable and precise predictions of essential amino acids in up to 44 NIR spectrometers. Different standardization techniques were compared, and the effectiveness of using ...
Brega Elisa - - 2004
Candida albicans is an important human pathogen that displays a remarkable ability to detect changes in its environment and to respond appropriately by changing its cell morphology and physiology. Serum- and amino acid-based media are known to induce filamentous growth in this organism. However, the mechanism by which amino acids ...
Manzini Ivan - - 2004
In olfactory receptor neurons (ORNs) of aquatic animals amino acids have been shown to be potent stimuli. Here we report on calcium imaging experiments in slices of the olfactory mucosa of Xenopus laevis tadpoles. We were able to determine the response profiles of 283 ORNs to 19 amino acids, where ...
Mevi-Schütz Jovanne - - 2004
It is generally assumed that butterflies, as is the case with many holometabolous insects, rely primarily on nutrients gathered by larval feeding for somatic maintenance and fecundity. These reserves can be supplemented by adult feeding and in some cases by nuptial gifts passed from the males to the females during ...
Kimball Scot R - - 2004
The role of amino acids as substrates for protein synthesis is well documented. However, a function for amino acids in modulating the signal transduction pathways that regulate mRNA translation has only recently been described. Interesting, some of the signaling pathways regulated by amino acids overlap with those classically associated with ...
Grier Robert E - - 2004
Determination of plasma amino acid levels has become a key piece of information in the diagnosis and clinical management of a group of metabolic genetic disorders. Appropriate laboratory methodologies have been published for amino acid analysis, yet there is a need for direction for the laboratory in performing this testing. ...
Fujii Noriko - - 2004
Before the emergence of life, left-handed amino acids (L-enantiomers) were selected and right-handed amino acids (D-enantiomers) were eliminated on the primal earth. Nevertheless, with the progress of analytical methods, D-amino acids have recently been found in higher order living organisms in the form of free amino acids, peptides, and proteins. ...
Townsend Danyelle M - - 2004
Sulfur containing amino acids contribute substantially to the maintenance and integrity of cellular systems by influencing cellular redox state and cellular capacity to detoxify toxic compounds, free radicals and reactive oxygen species. Methionine and cysteine are the two primary sulfur-containing amino acids in mammals. Methionine is an essential amino acid, ...
Moughan Paul J - - 2003
It is important to be able to characterise foods and feedstuffs according to their available amino acid contents. This involves being able to determine amino acids chemically and the conduct of bioassays to determine amino acid digestibility and availability. The chemical analysis of amino acids is not straightforward and meticulousness ...
Tosh Colin R - - 2003
Many studies have paid particular attention to the role of either secondary plant compounds or amino acids as determinants of host-plant range in phytophagous insects. Here we examine the relative importance of both of these classes of compound in host acceptance by generalist and specialist morphs of the black bean ...
Jimenez-Villarreal J R - - 2003
The impact of beef trimmings treated with either 0.5% cetylpyridinium chloride (CPC), 200-ppm chlorine dioxide (CLO), 2% lactic acid (LA) or 10% trisodium phosphate (TSP) and an untreated control (C) prior to grinding, on instrumental color, sensory characteristics, TBARS values, pH and Lee-Kramer shear under simulated retail display were evaluated. ...
Casal Susana - - 2003
This work reports the results for the composition of robusta and arabica coffee species in terms of their amino acid enantiomers in the green and roasted states. The analyses were conducted for the free amino acids, as well as for the amino acids obtained after acid hydrolysis. The amino acids ...
Hu Weimin - - 2003
Staplabin and SMTPs, triprenyl phenol metabolites of the fungus Stachybotrys microspora, are a family of non-lysine-analog plasminogen modulators that enhance both activation and fibrin binding of plasminogen by modulating plasminogen conformation. These compounds, including SMTP-4, -5, -6, -7 and -8, have an amino acid or an amino alcohol moiety in ...
Bier Dennis M - - 2003
Tracer kinetic studies of amino acid metabolism during periods of high amino acid intake should allow insights into adaptive or maladaptive regulatory mechanisms controlling amino acid catabolic or disposal events before clinically evident effects. The principles of amino acid tracer kinetics have been well defined, but their application to establishing ...
Young Vernon R - - 2003
The proportions of amino acids in diets typical of human populations usually differ from the proportions in which they are required, although adverse effects due to such differences are not common. However, there is little systematic information about the adverse effects and the pathophysiological mechanisms of excessive intakes of single ...
Fuglsang Anders - - 2003
The genes from the genome of the AT-rich bacterium Campylobacter jejuni were analysed and characterised with respect to usage and amino acid usage. Codon usage is generally biased for all amino acids having synonymous codons, so that AT-rich synonyms are most frequently used. Markov chain analysis showed that codon bias ...
Liu Xin - - 2003
Window profiles of amino acids in protein sequences are used to describe the amino acid environment. The relative entropy or Kullback-Leibler distance derived from these profiles is used as a measure of dissimilarity for comparison of amino acids and secondary structure conformations. Distance matrices of amino acid pairs at different ...
Shinada T - - 2003
Eight analogs 4A-7A and 4B-7B of philanthotoxin (PhTX) from wasp venom and nephilatoxin-8 (NPTX-8) from spider venom whose tyrosine or asparagine linker is replaced by squaryl (sq) amino acid or 4-amino squaryl (4-asq) amino acid have been synthesized in an efficient manner via coupling of N-acyl squaryl amino acid intermediate ...
Burdick Daniel J - - 2003
The association of ICAM-1 with LFA-1 plays a critical role in several autoimmune diseases. N-2-Bromobenzoyl L-tryptophan, compound 1, was identified as an inhibitor to the formation of the LFA-1/ICAM complex. The SAR of the amino acid indicates that the carboxylic acid is required for inhibition and that L-histidine is the ...
Wu Guang - - 2003
In this data-based theoretical analysis, we use the random approach to analyse the amino acid pairs in human beta-glucocerebrosidase in order to determine which amino acid pairs are more sensitive to 109 variants from missense mutant human glucocerebrosidase. The rationale of this study is based on our hypothesis and findings ...
Zhang Yifeng - - 2003
Mammals can taste a wide repertoire of chemosensory stimuli. Two unrelated families of receptors (T1Rs and T2Rs) mediate responses to sweet, amino acids, and bitter compounds. Here, we demonstrate that knockouts of TRPM5, a taste TRP ion channel, or PLCbeta2, a phospholipase C selectively expressed in taste tissue, abolish sweet, ...
Hrassnigg N - - 2003
In queen honey bees the free amino acid content in the haemolymph clearly depends on the physiological function and social environment of the individual. While in drones and workers the content of free amino acids increases after emergence until it reaches a peak in 5-day-old animals and decreases afterwards, the ...
Yoshimura Tohru - - 2003
L-Amino acids are predominant in living organisms, but D-amino acids such as D-alanine and D-glutamate also occur in all eubacterial cell walls. Moreover, even mammals contain endogenous D-amino acids: D-serine functions as a signaling molecule in mammalian brains, and D-aspartate acts as a mediator in endocrine systems. Various other D-amino ...
Köhidai L - - 2003
Amino acids are considered the oldest organic substances of the prebiotic evolution. Chemotactic effects of amino acid L-isomers investigated in the protozoan model Tetrahymena show that the chemotactic properties of amino acids are complex and depend on multiple physicochemical characteristics of the investigated ligands. The range of effectiveness is significantly ...
Pencharz Paul B - - 2003
A full review of the strengths and limitations of the various methods used to define amino acid requirements is provided. The focus is on the recent development of carbon oxidation techniques such as indicator amino acid oxidation and 24-h amino acid balance to determine dietary indispensable (essential) amino acid needs ...
Hamase Kenji - - 2002
Substantial amounts of D-amino acids are present in mammalian tissues; their function, origin and relationship between pathophysiological processes have been of great interest over the last two decades. In the present article, analytical methods including chromatographic, electrophoretic and enzymatic methods to determine D-amino acids in mammalian tissues are reviewed, and ...
Jacchieri Saul G - - 2002
Various procedures are employed to relate the structural tendencies of polypeptide chain fragments to amino acid residues that in general have low background frequencies. A numerical evaluation of the content of these amino acids, named amino acid diversity, is defined. Distributions of the amino acid diversity parameter in databases containing ...
Gao Xinsheng - - 2002
Target of Rapamycin (TOR) mediates a signalling pathway that couples amino acid availability to S6 kinase (S6K) activation, translational initiation and cell growth. Here, we show that tuberous sclerosis 1 (Tsc1) and Tsc2, tumour suppressors that are responsible for the tuberous sclerosis syndrome, antagonize this amino acid-TOR signalling pathway. We ...
Essén-Gustavsson B - - 2002
Glycogenolysis and lipolysis are essential for energy production in muscle during prolonged exercise but less is known about the role of amino acid metabolism. The aim was to study the effect of an endurance race on pro- and macroglycogen, triglycerides and amino acid concentrations in muscle and on selected blood ...
DeGabriel J - - 2002
In this study of the amino acid nutrition of a marsupial we tested three hypotheses: (a) that brushtail possums eat less when diets contain excesses or deficiencies in essential amino acids, (b) that brushtail possums choose diets that do not contain amino acid excesses, and (c) that amino acid consumption ...
Diasolua Ngudi Delphin - - 2002
Processed cassava (Manihot esculenta Crantz) roots provide more than 60% of the daily energy intake for the population of the Democratic Republic of Congo. Insufficiently processed cassava roots in a diet deficient in sulfur amino acid have been reported to cause the irreversible paralytic disease konzo, afflicting thousands of women ...
Matsumoto T - - 2002
Hydroxyapatite (HAp) was synthesized in the presence of a variety of amino acids in order to investigate the effect of amino acid on the crystallinity and the solubility characteristics of HAp in the HAp-synthesizing condition. In the results of X-ray diffraction analysis, HAp synthesized in the presence of glycine (HAp-Gly), ...
Rahbé Y - - 2002
Aphidius ervi Haliday (Hymenoptera, Braconidae) is an endophagous parasitoid of the pea aphid, Acyrthosiphon pisum (Harris) (Homoptera, Aphididae). This parasitoid strongly redirects host reproduction and metabolism to favour nutrition and development of its juvenile stages. Parasite-regulated biosynthesis and mobilization of nitrogen metabolites determine a significant increase of host nutritional suitability. ...
Noctor Graham - - 2002
The question of whether general control of amino acid synthesis exists in plants remains to be resolved. It is not known whether there is overall co-ordination of the biosynthesis of amino acids that are formed through distinct pathways. In this work, amino acid contents were measured in a large number ...
Ikehara Kenji - - 2002
We have previously proposed an SNS hypothesis on the origin of the genetic code (Ikehara and Yoshida 1998). The hypothesis predicts that the universal genetic code originated from the SNS code composed of 16 codons and 10 amino acids (S and N mean G or C and either of four ...
Muñoz Caro G M - - 2002
Amino acids are the essential molecular components of living organisms on Earth, but the proposed mechanisms for their spontaneous generation have been unable to account for their presence in Earth's early history. The delivery of extraterrestrial organic compounds has been proposed as an alternative to generation on Earth, and some ...
Bernstein Max P - - 2002
The delivery of extraterrestrial organic molecules to Earth by meteorites may have been important for the origin and early evolution of life. Indigenous amino acids have been found in meteorites-over 70 in the Murchison meteorite alone. Although it has been generally accepted that the meteoritic amino acids formed in liquid ...
Hoffman Robert V - - 2002
The reduction of N-protected amino ketones can be carried stereoselectively to produce either the syn- or anti-amino alcohol diastereomer. Carbamate-protected amino ketones can be reduced predictably and selectively to anti-amino alcohols with LiAlH(O-t-Bu)3 in ethanol at -78 degrees C. N-Trityl-protected amino ketones can be reduced selectively to syn-amino alcohols with ...
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