Plasma Amino Acids in Young and Older Adult Human Subjects

1964 ◽  
Vol 10 (1) ◽  
pp. 32-40 ◽  
Author(s):  
Philip G Ackermann ◽  
Teofil Kheim
Keyword(s):  
Amino Acids ◽  
Older Adult ◽  
Human Subjects ◽  
The Elderly ◽  
Essential Amino Acids ◽  
Older Individuals ◽  
Isoleucine Leucine ◽  
Younger Adults ◽  
Chromatographic Procedure ◽  
Older Subjects

Abstract Nineteen amino acids were determined in the plasma of young and older individuals by the chromatographic procedure of Moore, Spackman, and Stein (7,8). Of the essential amino acids, valine, methionine, isoleucine, leucine, phenylalanine, and lysine were found to be lower in older subjects. In all, 11 of the 19 amino acids studied showed lower values in these individuals, indicating some differences in protein metabolism between the elderly and younger adults.

USE OF GLUTAMIC ACID-U-C14 TO DETERMINE NUTRITIONALLY ESSENTIAL AMINO ACIDS FOR LARVAE OF THE BLOW FLY, PHORMIA REGINA

1960 ◽  
Vol 38 (11) ◽  
pp. 1229-1234 ◽  
Author(s):  
R. Kasting ◽  
A. J. McGinnis
Keyword(s):  
Amino Acids ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Essential Amino Acids ◽  
Phormia Regina ◽  
Blow Fly ◽  
Isoleucine Leucine ◽  
Low Level ◽  
Third Instar Larvae

The production of C14O2 by third-instar larvae of the blow fly, Phormia regina Meig., after it was injected with glutamic acid-U-C14, indicates that this substrate was metabolized under these conditions. However, the nutritionally essential amino acids lysine, phenylalanine, valine, isoleucine, leucine, and threonine, isolated from the injected larvae, contained little radioactivity. A low level of radioactivity in arginine, histidine, and methionine suggests that they were slowly synthesized. The nutritionally non-essential amino acids alanine, serine, aspartic acid, and proline contained large quantities of radioactivity; tyrosine and glycine were exceptions. These results, in agreement with earlier work that used glucose-U-C14, show that radioactivity data are useful for determining certain of the nutritionally essential amino acids.

scholarly journals Effect of nitrogen fertilization on metabolisms of essential and non-essential amino acids in field-grown grain maize (Zea mays L.)

2010 ◽  
Vol 56 (No. 12) ◽  
pp. 574-579 ◽  
Author(s):  
T. Lošák ◽  
J. Hlušek ◽  
R. Filipčík ◽  
L. Pospíšilová ◽  
J. Maňásek ◽  
...  
Keyword(s):  
Amino Acids ◽  
Zea Mays ◽  
Field Experiments ◽  
Zea Mays L ◽  
Tricarboxylic Acid Cycle ◽  
Essential Amino Acids ◽  
Isoleucine Leucine ◽  
N Dose ◽  
Limiting Amino Acid ◽  
Nitrogen Rates

In two-year field experiments, nitrogen (N) in the form of urea (0, 120 and 240 kg N/ha) was applied to grain maize (Zea mays L.) hybrid KWS 2376. The two-year mean content of total grain N at harvest was 1.54%. The highest N dose reduced most of the 17 amino acids (AA) analysed in the grain compared with the other treatments. Possible reasons for this could be an adverse effect on the tricarboxylic acid cycle or deficiency of carbon skeletons for the assimilation of NH<sub>4</sub><sup>+</sup> into amides and amino acids. The content of the limiting amino acid lysine was not influenced by N fertilisation, with a mean two-year content of 2.02 mg/g DM. Taking into account the differences in fertilisation, the effect of the year was seen in the maximal accumulation of amino acids serine, proline, methionine, threonine, arginine and lysine. Increasing rates of nitrogen reduced the accumulation of asparagine and glycine, and, on the contrary, increased the accumulation of tyrosine. Nitrogen rates have a significant effect on the maximal accumulation of valine, isoleucine, leucine, phenylalanine, histidine, cysteine and alanine and appeared as early as after the first increased rate of nitrogen (120 kg N/ha).

The Processing of Synthetic Speech by Older and Younger Adults

1992 ◽  
Vol 36 (2) ◽  
pp. 190-192 ◽  
Author(s):  
Janan Al-Awar Smither
Keyword(s):  
Short Term Memory ◽  
Memory Task ◽  
The Elderly ◽  
Synthetic Speech ◽  
Text To Speech ◽  
Short Term ◽  
Younger Adults ◽  
Term Memory ◽  
Response Systems ◽  
Older Subjects

This experiment investigated the demands synthetic speech places on short term memory by comparing performance of old and young adults on an ordinary short term memory task. Items presented were generated by a human speaker or by a text-to-speech computer synthesizer. Results were consistent with the idea that the comprehension of synthetic speech imposes increased resource demands on the short term memory system. Older subjects performed significantly more poorly than younger subjects, and both groups performed more poorly with synthetic than with human speech. Findings suggest that short term memory demands imposed by the processing of synthetic speech should be investigated further, particularly regarding the implementation of voice response systems in devices for the elderly.

The effect of starvation and low nitrogen intakes on the concentration of free amino acids in the blood plasma and on the nitrogen metabolism in sheep

1970 ◽  
Vol 21 (5) ◽  
pp. 723 ◽  
Author(s):  
J Leibholz
Keyword(s):  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Dry Matter ◽  
Control Diet ◽  
Amino Nitrogen ◽  
Essential Amino Acids ◽  
Isoleucine Leucine ◽  
Plasma Urea ◽  
Low Nitrogen

Crossbred wethers were given a control diet (8 g nitrogen, 730 g dry matter daily) or a low nitrogen diet (0.5 g nitrogen, 520 g dry matter daily) or starved, for a 12 or 20 day experimental period. The concentrations of free serine, glutamine, glycine, alanine, histidine, and arginine in the plasma of the starved sheep decreased significantly while the concentrations of lysine, 3-methylhistidine, and isoleucine increased significantly. The ratio of essential to non-essential amino acids increased from 0.35 to 0.56 in the starved sheep. In sheep on the low nitrogen diet, the ratio of essential to non-essential amino acids in the plasma decreased from 0.40 to 0.27, with significant increases in the concentrations of glutanlic acid, glutamine, glycine, isoleucine, leucine, and 3-methylhistidine. Starvation and the low nitrogen diet both resulted in a reduction of the plasma urea concentrations. Starvation and the low nitrogen diet resulted in a 20-50 % reduction in the flow of saliva and a 40-78% increase in the concentration of total nitrogen. This resulted in no significant change in the daily secretion of nitrogen in the saliva. The concentration of urea in the saliva was increased by 3-54%. The concentrations of individual free amino acids in saliva are reported. The nitrogen content of the rumen was reduced, and after 7 days of starvation or on the low nitrogen diet all rumen nitrogen could be attributed to ammonia and free �-amino nitrogen.

Effect of Aging on Free Amino Acids and Electrolytes in Leg Skeletal Muscle

1979 ◽  
Vol 56 (5) ◽  
pp. 427-432 ◽  
Author(s):  
P. Möller ◽  
J. Bergström ◽  
S. Eriksson ◽  
P. Fürst ◽  
K. Hellström
Keyword(s):  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Statistical Significance ◽  
Plasma Concentrations ◽  
The Elderly ◽  
Essential Amino Acids ◽  
Elderly Men ◽  
Healthy Elderly ◽  
The Difference

1. The concentrations of electrolytes and free amino acids in plasma and the quadriceps femoris muscle were studied in ten apparently healthy elderly men, 52–77 years of age. The results were compared with those previously recorded for men 20–36 years old. 2. The two groups of subjects did not differ with regard to serum electrolytes and intracellular water content but the extracellular water in the older subjects exceeded that of the younger group by about 50%. The muscle specimens of the elderly men were also characterized by a 40% elevation of their total contents of Na+ and Cl−, whereas the content of K+ and Mg2+ was almost identical in both groups. 3. The means recorded for the plasma concentrations of most amino acids tended to be higher in the elderly men. The differences reached statistical significance for tyrosine, histidine, valine, lysine and total essential amino acids. In keeping with the findings in plasma, the amino acid concentrations in the muscle of the older group tended to exceed those of the younger ones. The difference reached statistical significance with regard to total amino acids, essential and non-essential amino acids, aspartate, alanine, citrulline, histidine, arginine, leucine and lysine. The various mechanisms that may contribute to these findings are discussed.

scholarly journals Use of plasma-free amino acids as biomarkers for detecting and predicting disease risk

2020 ◽  
Vol 78 (Supplement_3) ◽  
pp. 79-85
Author(s):  
Kenji Nagao ◽  
Takeshi Kimura
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino ◽  
Disease Risk ◽  
The Elderly ◽  
Essential Amino Acids ◽  
Clinical Findings ◽  
Amino Acid Supplementation ◽  
Diabetes Prediction ◽  
Plasma Free Amino Acids

Abstract This paper reviews developments regarding the use of plasma-free amino acid (PFAA) profiles as biomarkers for detecting and predicting disease risk. This work was initiated and first published in 2006 and was subsequently developed by Ajinomoto Co., Inc. After commercialization in 2011, PFAA-based tests were adopted in over 1500 clinics and hospitals in Japan, and numerous clinician-led studies have been performed to validate these tests. Evidence is accumulating that PFAA profiles can be used for diabetes prediction and evaluation of frailty; in particular, decreased plasma essential amino acids could contribute to the pathophysiology of severe frailty. Integration of PFAA evaluation as a biomarker and effective essential amino acid supplementation, which improves physical and mental functions in the elderly, could facilitate the development of precision nutrition, including personalized solutions. This present review provides the background for the technology as well as more recent clinical findings, and offers future possibilities regarding the implementation of precision nutrition.

scholarly journals Inter-Individual Nectar Chemistry Changes of Field Scabious, Knautia arvensis

Insects ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 75
Author(s):  
Christine Venjakob ◽  
Sara Leonhardt ◽  
Alexandra-Maria Klein
Keyword(s):  
Amino Acids ◽  
Plant Species ◽  
Plant Community ◽  
Individual Variation ◽  
Abiotic Factors ◽  
Essential Amino Acids ◽  
Nutritional Composition ◽  
Community Context ◽  
Isoleucine Leucine ◽  
Nectar Chemistry

Nectar is crucial to maintain plant-pollinator mutualism. Nectar quality (nutritional composition) can vary strongly between individuals of the same plant species. The factors driving such inter-individual variation have however not been investigated closer. We investigated nectar quality of field scabious, Knautia arvensis in different grassland plant communities varying in species composition and richness to assess whether nectar quality can be affected by the surrounding plant community. We analyzed (with high performance liquid chromatography) the content of carbohydrates, overall amino acids, and essential amino acids. Amino acid and carbohydrate concentrations and proportions varied among plant individuals and with the surrounding plant community but were not related to the surrounding plant species richness. Total and individual carbohydrate concentrations were lowest, while proportions of the essential amino acids, valine, isoleucine, leucine (all phagostimulatory), and lysine were highest in plant species communities of the highest diversity. Our results show that K. arvensis nectar chemistry varies with the composition of the surrounding plant community, which may alter the taste and nutritional value and thus affect the plant’s visitor spectrum and visitation rate. However, the strong inter-individual variation in nectar quality requires additional studies (e.g., in semi-field studies) to disentangle different biotic and abiotic factors contributing to inter-individual nectar chemistry in a plant-community context.

USE OF GLUTAMIC ACID-U-C14 TO DETERMINE NUTRITIONALLY ESSENTIAL AMINO ACIDS FOR LARVAE OF THE BLOW FLY, PHORMIA REGINA

1960 ◽  
Vol 38 (1) ◽  
pp. 1229-1234 ◽  
Author(s):  
R. Kasting ◽  
A. J. McGinnis
Keyword(s):  
Amino Acids ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Essential Amino Acids ◽  
Phormia Regina ◽  
Blow Fly ◽  
Isoleucine Leucine ◽  
Low Level ◽  
Third Instar Larvae

The production of C14O2 by third-instar larvae of the blow fly, Phormia regina Meig., after it was injected with glutamic acid-U-C14, indicates that this substrate was metabolized under these conditions. However, the nutritionally essential amino acids lysine, phenylalanine, valine, isoleucine, leucine, and threonine, isolated from the injected larvae, contained little radioactivity. A low level of radioactivity in arginine, histidine, and methionine suggests that they were slowly synthesized. The nutritionally non-essential amino acids alanine, serine, aspartic acid, and proline contained large quantities of radioactivity; tyrosine and glycine were exceptions. These results, in agreement with earlier work that used glucose-U-C14, show that radioactivity data are useful for determining certain of the nutritionally essential amino acids.

THE STIMULATION OF INSULIN RELEASE BY ESSENTIAL AMINO ACIDS FROM RABBIT PANCREAS IN VITRO

1970 ◽  
Vol 47 (3) ◽  
pp. 347-356 ◽  
Author(s):  
R. D. G. MILNER
Keyword(s):  
Amino Acids ◽  
Insulin Release ◽  
Incubation Medium ◽  
Statistical Significance ◽  
Adenosine Monophosphate ◽  
Essential Amino Acids ◽  
Isoleucine Leucine ◽  
Rabbit Pancreas

SUMMARY Pieces of rabbit pancreas were incubated in vitro in an incubation medium containing no glucose or 1·5 mg. glucose/ml. In each of these conditions the effect on insulin release of each of the essential amino acids at 5 mm concentration was studied. Leucine was the only essential amino acid that stimulated insulin release to a level which reached statistical significance in an incubation medium containing no glucose. In medium containing 1·5 mg. glucose/ml., arginine, isoleucine, leucine and lysine stimulated insulin release and phenylalanine inhibited insulin release. Glucagon, theophylline or dibutyryl cyclic adenosine monophosphate stimulated insulin release significantly in the presence of leucine but not in the presence of arginine. Arginine stimulated insulin release in the presence of leucine. The results of these experiments characterize further the difference in the mechanism of action of leucine and arginine on the pancreatic β-cell and indicate possible explanations for results obtained in other species in vivo.

Amino Acid Composition of Fishery Products

1949 ◽  
Vol 7c (9) ◽  
pp. 513-521 ◽  
Author(s):  
Catherine P. Deas ◽  
H. L. A. Tarr
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Essential Amino Acids ◽  
Waste Materials ◽  
Small Peptides ◽  
Isoleucine Leucine ◽  
Fish Flesh ◽  
Microbiological Methods ◽  
Fishery Products ◽  
Muscle Myosin

Fish flesh and certain waste materials were hydrolysed by tryptic enzymes of fish pyloric caeca. Fractionation of the resulting hydrolysates showed that they contained largely peptone, sub-peptone and residual (small peptides and amino acids) nitrogen, and little or no protein or proteose nitrogen. Fish flesh, milts, roes, meal, stickwater and a muscle myosin preparation were extracted to remove the fat, then dried and hydrolysed with acid or alkali. The essential amino acids arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, valine, tryptophane and tyrosine were determined in these enzyme-, acid- and alkali-hydrolysed materials by microbiological methods. The results have been summarized.

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