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PubMed1984

Immunochemical studies of a purified antigen from Micropolyspora faeni.

A pure antigen fraction was isolated from the crude culture filtrate of Micropolyspora faeni by gel filtration and affinity chromatography. The isolated antigen has a mol. wt of approximately 16,000 and an isoelectric point of pH 3.8. The major amino acid content of this fraction includes glycine, glutamic acid, aspartic acid and alanine. This antigen fraction reacted with the sera of all 15 farmer's lung patients and 20 asymptomatic farmers with circulating anti-M. faeni antibodies. An ELISA method was developed using the purified antigen to detect specific circulating antibodies against M. faeni in farmer's lung patients.

Amino Acids↗
PubMed1988

Determination of beta-N-methylamino-L-alanine (BMAA) in plant (Cycas circinalis L.) and animal tissue by precolumn derivatization with 9-fluorenylmethyl chloroformate (FMOC) and reversed-phase high-performance liquid chromatography.

A high-performance liquid chromatography (HPLC) method is described for determining subpicomole concentrations of beta-N-methylamino-L-alanine (BMAA) in plant and animal tissue. BMAA and other amino acids were reacted with 9-fluorenylmethyl chloroformate (FMOC) for 10 min under alkaline conditions to form highly fluorescent and stable derivatives. All amino acids, including BMAA, eluted from the column within 22 min. BMAA (tr = 18.02 +/- 0.07 min) was detected in Cycas circinalis L. seed and in serum, cerebrospinal fluid and brain tissue from BMAA-treated monkeys and rats. The primary amino acids glutamine, glutamic acid, aspartic acid, alanine, glycine and gamma-aminobutyric acid (GABA) could also be detected since they were well resolved from BMAA. These amino acids and BMAA were linear over the concentration range of 0.15-7.5 microM with a relative standard deviation ranging from 2.1-6.7%. This method should prove useful in studies to determine the role of BMAA in the Western Pacific amyotrophic lateral sclerosis/Parkinsonism-dementia complex for which cycad seed is the principal etiological candidate.

Amino Acids, Diamino↗
PubMed1991

Rat prostatic growth factors: purification and characterization of high and low molecular weight epidermal growth factors from rat dorsolateral prostate.

Growth factors which possibly participate in androgen-induced proliferation of rat prostate epithelial cells have been purified and characterized. Four distinct forms of growth factor were found in the extract of rat dorsolateral prostate. One of the factors was a member of heparin-binding growth factor (HBGF) family judging from its high affinity for heparin-Sepharose. The other three factors were capable of competing with [125I]epidermal growth factor (EGF) for the cell surface receptor, and recognized by anti-rat EGF antiserum. These EGF-like factors (EGF1-EGF3) were purified by ion-exchange chromatography, gel filtration and reverse phase HPLC. EGF1 showed microheterogeneity on chromatographic and electrophoretic separation and N-terminal sequence analysis. EGF1 showed an average molecular weight of about 35,000 on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions. These results indicated that EGF1 was a mixture of high molecular weight forms of EGF. The molecular weights of EGF2 and EGF3 were similar to that of rat submaxillary gland EGF (Mr = 5400). The amino acid sequence of EGF2 was identical with that of rat EGF except for the N- and C-terminal amino acids: aspartic acid instead of asparagine was found at the N-terminal position and C-terminal arginine was missing in EGF2. Although the N-terminal sequence of EGF3 (1-19) was identical with that of EGF2, the two factors were completely separated by gel filtration indicating a difference in the C-terminal structure. EGF1, EGF2 and EGF3 but not HBGF stimulated proliferation of primary cultured rat dorsolateral prostate epithelial cells.

Amino Acid Sequence↗
PubMed1995

Substance P is a possible neurotransmitter in the rat spinothalamic tract.

In order to shed some light on the neurotransmitters in the spinothalamic tract (STT), we examined, biochemically and immunohistochemically, the contents of various neurotransmitter candidates in the terminal field of the STT after cervical hemi-chordotomy (HC) and dorsal quadrant-chordotomy (dQC) in the rat. Substance P (SP), calcitonin gene-related peptide (CGRP), enkephalin, neuropeptide Y, neurotensin, oxytocin and dynorphin A were analyzed immunohistochemically. The contents of neuropeptides (SP, CGRP and cholecystokinin octapeptide) were measured by radioimmunoassay and those of amino acids (aspartic acid, glutamic acid, gamma-aminobutyric acid (GABA) and glycine) and noradrenaline were determined using high-performance liquid chromatography. Cervical hemi-chordotomy, but not dQC, caused significant decreases of the SP-like immunoreactivity in and SP content of the ventral thalamus on the ipsilateral side, compared with that on the contralateral side and of rats subjected to sham-operation. However, neither HC nor dQC resulted in any changes in the ventral thalamic contents of other putative neurotransmitters examined. These results suggest that, in rats, the STT contains SP and that SP-positive fibers run in the ventral half of the ascending spinal tract at the cervical level.

Amino Acids↗
PubMed1991

Changes in plasma and urinary amino acid levels during diabetic ketoacidosis in children.

Plasma and urinary concentrations of different amino acids were investigated during diabetic ketoacidosis (DKA) and 12, 24, 72 hours after initiation of therapy. In DKA, plasma concentration of glutamic acid, aspartic acid, valine, leucine and isoleucine significantly increased while that of asparagine and glutamine decreased compared to levels in well-controlled diabetic patients. The urinary excretion of branched-chain amino acids, histidine, serine and threonine was elevated while those of glutamic acid, glutamine, glycine and taurine were reduced. Among the different amino acids, histidine excretion had the highest variability. A strong correlation was found between the urinary excretion of several amino acids and that of the beta-2-microglobulin characterizing tubular dysfunction. Changes in the excretion of different amino acids reflect the altered metabolic state and renal function due to DKA.

Adolescent↗
PubMed1992

An investigation of Japanese subjects maps susceptibility to type 1 (insulin-dependent) diabetes mellitus close to the DQA1 gene.

Insulin-dependent diabetic and control subjects of Japanese origin were HLA-DRB1, -DQB1, and -DQA1 typed using restriction fragment length polymorphism analysis and sequence-specific oligonucleotide gene probing. The DQA1 allele DQA1*0301 was positively associated with the disease [48/52 (92%) diabetic patients versus 44/64 (69%) control subjects, Pc less than 0.03, RR = 4.97]. Alleles of the DRB1 and DQB1 genes showed no significant association with the disease. The frequency of DQB1 genotypes encoding the amino acid aspartic acid at position 57 of the DQ beta chain did not differ significantly between subjects with insulin-dependent diabetes mellitus (IDDM) and controls. These findings suggest that a susceptibility allele for IDDM in the Japanese is more closely associated with the DQA1 gene than the DQB1 gene.

Alleles↗
PubMed1994

A competitive enzyme-linked immunoassay for domoic acid determination in human body fluids.

A polyclonal antiserum was raised in mice against domoic acid. Two of three immunogens consisted of domoic acid coupled to ovalbumin (OVA) and keyhole limpet haemocyanin at molar ratios of 47:1 and 44:1, respectively using a carbodiimide reaction. Titres of both antisera exceeded 1/35,000 against domoic acid coupled to the non-relevant carrier. Domoic acid was also conjugated to bovine serum albumin at a molar ratio of 30:1 using N-hydroxysuccinimidyl-4-azidobenzoate, a photoreactive compound. This immunogen, however, produced no measurable serum titres against domoic acid. The antiserum produced against the OVA conjugate displayed the highest affinity for free domoic acid in competitive enzyme-linked immunosorbent assay (ELISA). Furthermore, this antiserum preparation did not significantly cross-react with glutamic acid, aspartic acid, the structural analogue kainic acid, or the paralytic shellfish toxin, saxitoxin. The competitive ELISA was used to quantify domoic acid concentrations in human body fluids spiked with pure domoate. The lower limits of accurate domoic acid determinations in competitive ELISA were 0.2 micrograms/ml in urine, 0.25 micrograms/ml in plasma and 10 micrograms/ml in milk. It was concluded that the competitive ELISA described herein could be used to quantitate directly the concentration of domoic acid in the body fluids of individuals with amnesic shellfish poisoning.

Animals↗
PubMed1987

Pyroglutamyl N-termini of thermal polyamino acids.

It has been established indirectly that the N-termini of the thermal polyamino acids are pyroglutamic acid. This was determined by trifluoroacetic acid hydrolysis of the lactam ring followed by Dansyl labelling. The polyamino acids contained Ala, Gly, Glu, Leu, Phe, and Pro. In the experiments described here, the presence of pyroglutamic acid at the N-terminus of a polyamino acid was determined directly by the use of pyrrolidone carboxylyl peptidase. The enzyme catalyzes the removal of pyroglutamyl residues at the N-terminus of polypeptide chains. The polyamino acids used in these studies contained glutamic acid, aspartic acid, alanine, glycine, isoleucine, proline and valine. Alkaline hydrolysis was also used to determine indirectly that the N-termini of these polyamino acids are pyroglutamic acid. Another interesting finding was that many of the amino acids in the polymerization mixture were found to occur penultimate to the N-terminal amino acid. This is interpreted to mean that the diffusible fraction contains many polyamino acids.

Amino Acid Sequence↗
PubMed1993

Purification and analysis of a human sarcoma associated antigen.

S1, a heterophile antigen present on human sarcoma cell lines in culture, has been previously defined by this laboratory [1,2]. This antigen is also present in guinea-pig kidney. Purification of the antigen to homogeneity has now been achieved by a combination of ammonium sulfate fractionation, DEAE-cellulose, sephadex, high pressure liquid chromotography and affinity chromotography. S1 is a monomeric protein of 70,000 Da, as indicated by the presence of a single band on SDS-PAGE. Amino acid analysis demonstrates the prevalence of glycine, lysine and glutamic acid. Aspartic acid was found to be the N-terminal residue with further sequence of glycine-valine-alanine-glutamic acid (gly-val-ala-glut).

Amino Acids↗
PubMed1984

Isolation and immunohistochemical localization of a cerebellar protein.

Our previous report described that a protein called spot 35 is found in the cerebellar cytosol of adult rats by two-dimensional gel electrophoresis. In this paper we isolated this protein from the soluble fraction of bovine and rat cerebella and then prepared an antiserum against the bovine protein. This protein shows pI around 5.3 and Mr around 27 kdalton. Determination of the amino acid composition of this protein shows high glutamic acid, aspartic acid and leucine contents. Using the antiserum we examined the immunohistochemical localization of this protein by the peroxidase-antiperoxidase method. Purkinje cells, their dendrites and axons were immunohistochemically stained in the cerebella of adult rats, rabbits and humans. Other cells, such as granule cells and glial cells, and myelin did not react to the antiserum.

Amino Acids↗
PubMed1983

Putative amino acid neurotransmitters and the nucleus dorsomedialis thalamus-prefrontal cortex pathway in the rat.

Endogenous levels of putative amino acid neurotransmitters (glycine, glutamic acid, aspartic acid, and GABA) in medial and sulcal prefrontal cortex of the rat were analyzed using gas liquid chromatography. No changes were found in the levels of these amino acids in medial and sulcal prefrontal cortex after lesion of the nucleus dorsomedialis of the thalamus suggesting, therefore, that the NDMT-prefrontal cortex pathway is not mediated by these amino acids.

Amino Acids↗
PubMed1995

Preparative-scale amino acid separation by thermal parametric pumping on an ion-exchange resin.

Thermal parametric pumping was experimentally investigated for the concentration and separation of amino acids. Previous theories of parametric pumping were improved by taking into account dissociation equilibria in the liquid phase. Experiments were carried out with a mixture of glutamic acid, aspartic acid, serine and threonine in a highly acidic solution (HCl). A multi-component equilibrium model was mainly used to simulate the experimental results and to investigate the effect of chloride concentration over a wide range. It is shown that it is always possible to concentrate the amino acids and to separate some of them under certain conditions.

Amino Acids↗
PubMedDate not supplied

Elevated cerebrospinal fluid histidine in alcohol withdrawal.

Cerebrospinal fluid (CSF) histidine concentration was significantly elevated in seven patients early in the alcohol withdrawal syndrome (206.3 +/- 74.4 (SEM) nanomols/ml CSF). When these same patients were restudied an average of six days later when alcohol withdrawal was clinically resolved, their mean CSF histidine concentration continued to be significantly elevated (164.7 +/- 24.7) when compared to normal (12.0 +/- 0.5 nanomols/ml CSF). Other amino acids (aspartic acid, serine, alanine, methionine, leucine, tyrosine, phenylalanine, lysine and arginine) showed no definite changes from normal, and no change during the course of alcohol withdrawal. Possible reasons for these high concentrations and the extreme variability (especially early in alcohol withdrawal) are discussed.

Adult↗
PubMedDate not supplied

Depressed convulsions by diazepam and its effects on brain monoamines and amino acids in E1 mice.

The effect of diazepam on inbred mutant E1 mice, which develop convulsive seizures after repeated sessions of being tossed up, was examined. Acute administration of diazepam (32 mg/kg, i.p.) completely inhibited the convulsions. At that time, the dopamine level was increased in the cortex and hippocampus, and the norepinephrine level in the cerebellum was decreased. 5-Hydroxytryptamine levels were not changed. As for amino acids, the glutamine level increased and the levels of GABA, glutamic acid, aspartic acid, alanine and other amino acids were not changed.

Amino Acids↗
PubMed1991

Intraepidermal distribution of free amino acids in porcine skin.

The study describes the vertical distribution of free amino acids in the porcine epidermis as compared to the human integument, using a micro-determination TLC method based on the reaction of amino acids with dansyl chloride. This microanalytical approach demonstrated 22 free amino acids, with the relatively largest amounts being present for acidic amino acids and their amides. It was obvious that the relative amounts of certain amino acids (alanine, proline, valine, glutamine, histidine, glycine, threonine) decreased, whereas acidic amino acids (glutamic acid, aspartic acid) increased from the stratum basale up to the stratum corneum. This distributional pattern could be verified for the dorsal and lateral body regions of the pig breeds used, and for man. The results obtained are discussed in view of the development of epidermal keratinization.

Amino Acids↗
PubMed2004

Biochemical dynamics of spermatogenesis and oogenesis in Eledone cirrhosa and Eledone moschata (Cephalopoda: Octopoda).

The effect of spermatogenesis and oogenesis on protein, lipid, glycogen, cholesterol and energy contents, total amino acid and fatty acid profiles of Eledone cirrhosa and Eledone moschata tissues (gonad, digestive gland and muscle) was investigated. A significant (p<0.05) increase in the amino acids and protein content of the gonad throughout sexual maturation (namely in oogenesis) was observed, but the allocation of these nitrogen compounds from the digestive gland and muscle was not evident. The major essential amino acids (EAA) in the three tissues were leucine, lysine and arginine. The major nonessential amino acids (NEAA) were glutamic acid, aspartic acid and alanine. A significant increase in lipid and fatty acid contents of gonad and digestive gland was observed. There was also little evidence of accumulated lipid storage reserves being used for egg production. It seems that for egg production Eledone species use energy directly from food, rather than from stored products. Most of saturated fatty acid (SFA) content of the three tissues was presented as 16:0 and 18:0, monounsaturated fatty acid (MUFA) content as 18:1 and 20:1 and polyunsaturated fatty acid (PUFA) content as 20:4n-6, 20:5n-3 and 22:6n-3. Cholesterol and glycogen contents significantly increased in gonad and digestive gland throughout maturation while the muscle revealed no obvious pattern. If Eledone's component sterols are of a dietary origin, a considerable variation in the cholesterol content between species might be expected on the basis of the sterol composition of their prey. Although spermatogenesis and oogenesis had a significant effect (p<0.05) in gonad and digestive gland energy content, the biochemical composition of digestive gland and muscle may not be primarily influenced by sexual maturation, but rather by other biotic factors such as feeding activity, food availability, spawning and brooding.

Animals↗
PubMed2005

Changes in amino acids and lipids during embryogenesis of European lobster, Homarus gammarus (Crustacea: Decapoda).

We studied the amino acid and lipid dynamics during embryogenesis of Homarus gammarus. Major essential amino acids (EAA) in the last stage of embryonic development were arginine, lysine and leucine; major nonessential amino acids (NEAA) were glutamic acid, aspartic acid, valine and glycine. The highest percent of utilization occurred in respect to EAA (27.8%), mainly due to a significant decrease (p<0.05) of methionine (38.3%) and threonine (36.0%). NEAA also decreased significantly (p<0.05, 11.4%), namely serine (38.1%), tyrosine (26.4%) and glutamic acid (25.7%). In contrast, the free amino acid content increased significantly (p<0.05) during embryonic development, especially the free nonessential amino acids (FNEAA). In the last stage, the most abundant FNEAA were glycine, proline, alanine and taurine, and the major free essential amino acids (FEAA) were arginine, lysine and leucine. Lipid content decreased significantly (p<0.05) during embryonic development. A substantial decrease in all neutral lipid classes was observed (>80% of utilization). Major fatty acids were 16:0, 18:0, 18:1n-9, 18:2n-6, 18:3n-3, 20:5n-3 and 22:6n-3. Unsaturated (UFA) and saturated fatty acids (SFA) were used up at similar rates (76.5% and 76.3%, respectively). Within UFA, monounsaturates (MUFA) were consumed more than polyunsaturates (PUFA) (82.9% and 67.5%, respectively).

Amino Acids↗
PubMed2005

Chemical characterisation of eggs from deep-sea sharks.

The chemical characterisation and nutritional value of eggs from the five deep-sea sharks leafscale gulper shark (Centrophorus squamosus), greater lantern shark (Etmopterus princeps), longnose velvet dogfish (Centroscymnus crepidater), Portuguese dogfish (Centroscymnus coelolepis) and black dogfish (Centrocyllium fabricii) captured at Hatton Bank in the North Atlantic were examined. The chemical composition was quite similar for all the eggs studied. The dominant fatty acid in all the eggs was the monounsaturated fatty acid C18:1, which varied from 27-39%. The eggs had a relatively high content of C16:0 (13.0-18.5%) and C22:6n-3 (10.3-15.1%). The two main lipid classes in the eggs were triacylglycerols (36-55%) and phospholipids (34-41%). The eggs had high amounts of vitamin A and E. The shark eggs were particularly rich in the amino acids aspartic acid, glutamic acid, leucine and arginine.

Amino Acids↗