scholarly journals Chemical compositions of elastins isolated from aortas and pulmonary tissues of humans of different ages

1972 ◽  
Vol 127 (1) ◽  
pp. 261-269 ◽  
Author(s):  
R. John ◽  
J. Thomas
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Cross Linking ◽  
Chemical Compositions ◽  
Amino Acid Compositions ◽  
Different Ages ◽  
Older Subjects ◽  
The Cross ◽  
Carbohydrate Contents

1. Elastins were isolated from the visceral pleuras and parenchymas of lungs of humans of different ages. 2. The elastin content of pleuras increased whereas that of parenchymas remained constant with increasing age. 3. The amino acid compositions and carbohydrate contents of elastins isolated from both pulmonary tissues changed in the same way with increasing age of the subjects. These changes were similar to those observed in elastins isolated from the aorta. 4. Similar glycoproteins were isolated from pleuras and aortas, and were more difficult to extract from the elastins of older subjects. Contamination with these glycoproteins was responsible for the changes in composition of elastin, as the age of the tissue from which it was extracted increased. 5. The amount of the cross-linking amino acids desmosine and isodesmosine was lower in elastins isolated from both aorta and pulmonary tissues of senile subjects than those from younger subjects.

scholarly journals Relationships between electrolyte and amino acid compositions in sweat during exercise suggest a role for amino acids and K+ in reabsorption of Na+ and Cl- from sweat

PLoS ONE ◽  
2019 ◽  
Vol 14 (10) ◽  
pp. e0223381 ◽  
Author(s):  
Grace R. Murphy ◽  
R. Hugh Dunstan ◽  
Margaret M. Macdonald ◽  
Nattai Borges ◽  
Zoe Radford ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Compositions

scholarly journals A Mechanism for the Development of Chronic Traumatic Encephalopathy From Persistent Traumatic Brain Injury

2019 ◽  
Vol 13 ◽  
pp. 117906951984993 ◽  
Author(s):  
Melissa Demock ◽  
Steven Kornguth
Keyword(s):  
Traumatic Brain Injury ◽  
Amino Acid ◽  
Brain Injury ◽  
Tau Protein ◽  
Chronic Traumatic Encephalopathy ◽  
Hla Class I ◽  
Class I ◽  
Cross Linking ◽  
Neural Cells ◽  
The Cross

A mechanism that describes the progression of traumatic brain injury (TBI) to end-stage chronic traumatic encephalopathy (CTE) is offered in this article. This mechanism is based upon the observed increase in the concentration of both tau protein and of human leukocyte antigen (HLA) class I proteins; the HLA increase is expressed on the cell membrane of neural cells. These events follow the inflammatory responses caused by the repetitive TBI. Associated inflammatory changes include macrophage entry into the brain parenchyma from increased permeability of the blood-brain barrier (BBB) and microglial activation at the base of the sulci. The release of interferon gamma from the microglia and macrophages induces the marked increased expression of HLA class I proteins by the neural cells and subsequent redistribution of the tau proteins to the glial and neuronal surface. In those individuals with highly expressed HLA class I C, the high level of HLA binds tau protein electrostatically. The ionic region of HLA class I C (amino acid positions 50-90) binds to the oppositely charged ionic region of tau (amino acid positions 93-133). These interactions thereby shift the cellular localization of the tau and orient the tau spatially so that the cross-linking sites of tau (275-280 and 306-311) are aligned. This alignment facilitates the cross-linking of tau to form the intracellular and extracellular microfibrils of tau, the primary physiological characteristic of tauopathy. Following endocytosis of the membrane HLA/tau complex, these microfibrils accumulate and produce a tau-storage-like disease. Therefore, tauopathy is the secondary collateral process of brain injury, resulting from the substantial increase in tau and HLA expression on neural cells. This proposed mechanism suggests several potential targets for mitigating the clinical progression of TBI to CTE.

Isolation of a Crosslinked Peptide from Hitman Fibrin and Development of a Radioimmunoassay

1979 ◽  
Author(s):  
R. Canfield ◽  
B. Lahiri ◽  
R. D’Alisa ◽  
V. Butler ◽  
H. Nossel ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Factor Xiiia ◽  
Cross Linking ◽  
Edman Degradation ◽  
Cnbr Cleavage ◽  
Normal Hemostasis

Factor XIIIa introduces up to six crossllnklng bonds per molecule of fibrin; the bonds between the γ chains on adjacent fibrin molecules form most rapidly. Since cross linking is essential for normal hemostasis and is likely to be important in tests to detect thrombosis, we have attempted to develop a radioimmunoassay that exhibits specificity for the γ chain crosslinks. The immunogen consisted of a 54 amino acid, crosslinked peptide, isolated from purified human γ-γ chains following CNBr cleavage, gel filtration on Sephadex G-50 and ion-exchange chromatography on SP-Sephadex. Amino acid analysis and Edman degradation through step 24 confirmed the sequence of Chen and Doolittle (Biochemistry 10: i486, 1971), and the two degradation steps that failed to liberate the expected PTH-amino acids matched the reported location of the Gin-Lys crosslinks. Antisera were obtained against this immunogen coupled either to bovine thyroglobulin or bovine serum albumin. All antisera elicited bound immunogen that was covalently coupled to ribonuclease radiolabeled with 125I as a tracer. The unlabeled γ-γ, crosslinked peptide effectively inhibited binding (0.03-0.08 picomoles for 50% inhibition), while with some antisera up to 500 times more of the 27 amino acid γ monomer peptide was required for the same degree of inhibition. Fibrinogen and fragment D also were poor Inhibitors. The results Indicate that it is possible by radioimmunoassay to distinguish the COOH-termlnal region of the γ-γ dlmer from that of uncrosslinked molecules.

scholarly journals Ehrlich chromogens, probable cross-links in elastin and collagen

1988 ◽  
Vol 252 (2) ◽  
pp. 387-393 ◽  
Author(s):  
P D Kemp ◽  
J E Scott
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Absorption Coefficient ◽  
Cross Linking ◽  
Diazonium Salts ◽  
Gel Chromatography ◽  
Skin Collagen ◽  
Cross Links ◽  
End Group ◽  
15N Abundance

(1) Proteolytic digests of tissue elastin contain material which reacts with dimethylaminobenzaldehyde in acid solution (Ehrlich's reagent) to give a cherry-pink colour. This Ehrlich chromogen(s) [EC(s)] is similar to but not identical with EC(s) previously demonstrated in tissue collagens [Scott, Hughes & Shuttleworth (1979) Biosci. Rep. 1, 611-618]. Both ECs react with diazonium salts in acid to give coloured products. (2) Diazobenzene linked via a phenolic ester to polyacrylamide beads (Biogel P10) has been used to absorb ECs specifically and almost quantitatively from proteolytic digests. The coupled deeply coloured azo-EC-peptides were then recovered after mild alkaline cleavage from the support and purified by gel chromatography. (3) Using 15N-labelled NaNO2, the collagen azo-EC-peptides were prepared, and 15N abundance measured therein. The molar absorption coefficient of the azo-EC group was calculated (18,700) based on the assumption that each azo-EC group contained one 15N atom. (4) Collagen azo-EC-peptides contained glucose and galactose, whereas elastin azo-EC peptides did not. The amino acid patterns of the two peptides were quite different, the former being rich in polar amino acids, the latter containing much alanine. The patterns were compatible with an origin from the cross-linking regions of collagen and elastin respectively. (5) Quantitative (molar) comparisons of the azo-EC group content with amino acid, amino end-group and sugar contents, and azo-EC peptide molecular mass, suggest that a structure is present in the collagen azo-EC-peptides containing two EC groups shared between four peptide chains. Three peptide chains probably meet at each (cross-linking) EC group. (6) Based on this structure, about 15% of adult bovine skin collagen contains EC groups.

scholarly journals Amino Acid Compositions of 27 Food Fishes and Their Importance in Clinical Nutrition

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Bimal Mohanty ◽  
Arabinda Mahanty ◽  
Satabdi Ganguly ◽  
T. V. Sankar ◽  
Kajal Chakraborty ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Protein Content ◽  
High Performance ◽  
Crude Protein ◽  
Cold Water ◽  
Building Blocks ◽  
Crude Protein Content ◽  
Dietary Counseling ◽  
Amino Acid Compositions

Proteins and amino acids are important biomolecules which regulate key metabolic pathways and serve as precursors for synthesis of biologically important substances; moreover, amino acids are building blocks of proteins. Fish is an important dietary source of quality animal proteins and amino acids and play important role in human nutrition. In the present investigation, crude protein content and amino acid compositions of important food fishes from different habitats have been studied. Crude protein content was determined by Kjeldahl method and amino acid composition was analyzed by high performance liquid chromatography and information on 27 food fishes was generated. The analysis showed that the cold water species are rich in lysine and aspartic acid, marine fishes in leucine, small indigenous fishes in histidine, and the carps and catfishes in glutamic acid and glycine. The enriched nutrition knowledge base would enhance the utility of fish as a source of quality animal proteins and amino acids and aid in their inclusion in dietary counseling and patient guidance for specific nutritional needs.

scholarly journals New Light on Old Fingermarks: The Detection of Historic Latent Fingermarks on Old Paper Documents Using 1,2-Indanedione/zinc

2020 ◽  
Author(s):  
Jemmy T. Bouzin ◽  
Jason Merendino ◽  
Stephen M. Bleay ◽  
Georgina Sauzier ◽  
Simon W. Lewis
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Zinc Chloride ◽  
Preliminary Investigation ◽  
High Quality ◽  
Different Ages ◽  
Over Time ◽  
Paper Substrates

This study explores trends in the effectiveness of 1,2-indandione/zinc chloride (IND/Zn) for visualizing latent fingermarks on paper substrates of various ages. Preliminary investigation of contemporaneous documents showed that high quality fingermarks could be deposited through incidental handling, although smudging and overlapping were evident. IND/Zn was then applied to incidentally handled documents up to 80 years old and successfully developed potentially identifiable fingermarks, significantly increasing the established timescale for fingermark detection with amino acid sensitive reagents. The results indicate that IND/Zn remains effective over longer periods than has been previously demonstrated, although a comparison between documents of different ages suggest that progressive diffusion of the target amino acids occurs over time, affecting the proportion of potentially identifiable marks.The findings of this study reinforce the applicability of IND/Zn for the detection of historic latent fingermarks on old paper documents.

scholarly journals A structural model for desmosine cross-linked peptides

1978 ◽  
Vol 173 (2) ◽  
pp. 617-625 ◽  
Author(s):  
R P Mecham ◽  
J A Foster
Keyword(s):  
Amino Acid ◽  
Structural Model ◽  
Partial Sequence ◽  
Cross Linking ◽  
Amino Acid Residues ◽  
Cross Link ◽  
Link Model ◽  
The Cross ◽  
Precursor Molecules

Desmosine-enriched peptides were isolated from a thermolysin digest of bovine ligamentum nuchae elastin and a partial sequence was determined. A ‘two-cross-link’ model is proposed in which a second cross-link, perhaps lysinonorleucine, joins two peptide chains approx. 35 amino acid residues removed from the desmosine. Implied in this model is a certain asymmetry or directionality which places restrictions on the ‘sense’ of the peptide chains (either always parallel or anti-parallel) in order to align the cross-linking sites. Imposing such restrictions raises the possibility of specific alignment of elastin precursor molecules by microfibrillar proteins and/or aligning peptides on the precursor molecules themselves.

Utilization of amino acids by Trypanosoma brucei in culture: L-threonine as a precursor for acetate

Parasitology ◽  
1975 ◽  
Vol 71 (2) ◽  
pp. 311-326 ◽  
Author(s):  
G. A. M. Cross ◽  
R. A. Klein ◽  
D. J. Linstead
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Trypanosoma Brucei ◽  
Potent Inhibitor ◽  
Culture Media ◽  
Growth Cycle ◽  
Defined Medium ◽  
Amino Acid Compositions

The amino acid compositions of several culture media have been analysed and compared. The utilization and excretion of amino acids and other metabolites have been followed during growth of Trypanosoma brucei S42 in a defined medium. All of the added L-threonine was metabolized by the cells, even when it was present at elevated concentrations. Glucose was consumed throughout the growth cycle: glutamine was consumed more rapidly than glutamic acid, which was itself used at about the same rate as proline. Threonine was cleaved to form glycine and acetate, both of which accumulated in the medium. Alanine and succinate were excreted together with a small amount of pyruvate, but these three products accounted for less than half of the glucose used. CO2 production from glucose was not measured, but insignificant amounts of CO2 were produced from threonine. Tetraethylthiuram disulphide blocked the cleavage of threonine and was a potent inhibitor of trypanosome growth.

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