COMPOSITION OF EPIPHYSEAL CARTILAGE: V. AMINO ACID AND AMINO SUGAR COMPOSITION OF EPIPHYSEAL CARTILAGE OF RACHITIC CHICKS; CHANGES EFFECTED BY VITAMIN D3

1967 ◽  
Vol 45 (5) ◽  
pp. 729-734 ◽  
Author(s):  
J. D. Cipera

Nineteen amino acids and two amino sugars were identified in the epiphyseal cartilage of rachitic chicks, and their levels estimated. Investigation of the effect of oral administration of vitamin D3 on the levels of these amino acids and amino sugars showed that vitamin D3 increased significantly the levels of galactosamine and decreased the levels of hydroxyproline and of glycine. The decrease in the levels of proline and cystine and increase in that of methionine were not statistically significant.

2000 ◽  
Vol 70 (2) ◽  
pp. 181-195 ◽  
Author(s):  
P.I. Hynd

AbstractThe rôle of various classes of nutrients (energy substrates, vitamins, minerals, amino acids) in the production of wool and hair from follicles, is considered for a variety of animal species. The wool and hair follicle have evolved a number of interesting features of carbohydrate metabolism including glutaminolysis, aerobic glycolysis, significant activity of the pentose phosphate pathway, and storage and mobilisation of glycogen. Presumably the necessity to continue to produce fibre despite fluctuations in the supply of oxygen and nutrients has resulted in some of these unique features, while others reflect the high level of DNA and protein synthesis occurring in the follicle. While it is considered that energy does not normally limit fibre growth, the relative contributions of aerobic and anerobic metabolism will greatly influence the amount of ATP available for follicle activity, such that energy availability may at times alter fibre growth. Alopecia and deficient fibre growth are consistent outcomes of deficiencies of biotin, riboflavin, pyridoxine, folate and pantothenic acid, but the precise rôles of these vitamins in follicle function await elucidation. Folate, in particular appears to play an important rôle in wool production, presumably reflecting its involvement in methionine metabolism. Cholecalciferol (vitamin D) significantly alters fibre growth in cultured follicles; vitamin D receptors are located in the outer root sheath, bulb, and dermal papilla of the follicle; and alopecia occurs in humans with defects in the vitamin D receptor. Retinol (vitamin A), too, appears to influence follicle function by altering keratinocyte proliferation and differentiation, with direct effects on the expression of keratin genes. The receptors for the retinoids are present in the keratogenous zone, the outer root sheath, the bulb, and the sebaceous glands. Vitamin A may also act indirectly on follicle function by influencing the activity of the insulin-like and epidermal growth factors and by altering vitamin D activity. At present there is little evidence implicating alpha-tocopherol (vitamin E) or phytylmenaquinone (vitamin K) in follicular events. Of the minerals, only copper and zinc have been shown to have direct effects on follicle function, independent of effects on food intake. Copper has direct effects on the activity of an unidentified enzyme on oxidation of thiol groups to form disulphide linkages. Wool produced by copper-deficient sheep lacks crimp, is weak and lustrous. Copper is also necessary for the activity of tyrosinase and the tyrosinase-related proteins involved in melanin synthesis. Zinc, like copper, is required for the normal keratinization of fibres but again, the precise rôle has yet to be elucidated. While the importance of amino acid supply for wool growth has long been established, there are still some unaswered questions such as; what are the effects of amino acids on fibre growth in animals other than sheep; what are the characteristics of the amino acid transport genes and proteins operating in the wool and hair follicle; and what are the specific rôles for amino acids in follicle function.


PEDIATRICS ◽  
1961 ◽  
Vol 27 (4) ◽  
pp. 539-550 ◽  
Author(s):  
William L. Nyhan ◽  
Margaret Borden ◽  
Barton Childs

The amino acids of blood and urine have been investigated using chromatography on cation exchange columns in the study of a patient with idiopathic hyperglycinemia. Marked increases in concentrations of glycine, serine, alanine, isoleucine and valine were found in the plasma. These changes were not reflected in increased excretion of these amino acids in the urine (with the exception of glycine). Restriction of the dietary intake of protein resulted in a decrease in the concentrations of glycine and other amino acids in the blood and urine, and there was a concomitant decrease in the frequency and severity of episodes of acute illness. The oral administration of leucine was found to induce a decrease in the levels of a number of amino acids in the patient and in controls. Continued decrease during the 3 hours of observation was noted for serine, isoleucine and valine. A mild but progressive decrease in threonine concentration was observed in the controls, while in the patient the concentration increased after the administration of leucine. Decreased levels at 1½ hours, returning toward the fasting levels at 3 hours, were observed for alanine, taurine and glycine. These apparently normal responses to leucine loads were not mediated through increase in the urinary excretion of the amino acids involved, and the data are interpreted to indicate entry of these amino acids into cells.


1966 ◽  
Vol 19 (4) ◽  
pp. 667 ◽  
Author(s):  
DL Ingles

Sulphurous acid alone and in admixture with other stronger acids has been used to hydrolyse 5-amino, 5-N-cyclohexylamino, and 5-N-piperidino derivatives of 5-deoxy-l,2-O-isopropylidene-D-xylose. The bisulphite addition compounds of the corresponding amino sugars were thus isolated. Similarly, methyl 5-amino-5-deoxy- 2,3-O-isopropylidene-D-riboside was hydrolysed to yield the bisulphite addition compound of 5-amino-5-deoxy-D-ribose. Treatment of the bisulphite addition compound of 5-amino-5-deoxy-D-xylose with barium hydroxide gave the free amino sugar as a syrup in 96% yield. Removal of bisulphite from the addition compound of 5-X-cyclohexylamino-5-deoxy-D-xylose gave the free sugar in 30% yield together with an amino acid (XVI).


1978 ◽  
Vol 58 (2) ◽  
pp. 237-249 ◽  
Author(s):  
F. J. SOWDEN ◽  
H. MORITA ◽  
M. LEVESQUE

The nitrogenous products formed by 6 N HCl hydrolysis of a variety of peats including a cultivated mesic profile, a virgin humic profile, a sedge, a woody and a sphagnum fibric peat were studied. Peat fractions separated according to particle size, woody and herbaceous materials isolated from a peat sample, and Typha and Carex plants growing on peat soils were also analyzed. Of the two profiles examined, the cultivated mesic peat showed significant quantitative changes in the content of individual amino acids throughout the profile. Also the amino sugar and amino acid N increased to a maximum, then decreased. On the other hand, the virgin humic peat profile exhibited random variations in the content of the individual amino acids and in the amount of amino acid N. Of the other peats examined, the fibric sphagnum had the highest percentage of amino acid N. Among the separates, the 100- to 200-mesh material had the highest proportion of amino acid N. The amino acid composition of the plant remains from the peat was similar to that of the peat from which it was isolated. The amino acid composition of the Typha and Carex plants was different from that of peat in that 75% of their total N content could be accounted for on the basis of amino acid, amide and amino sugar N. The amounts of hydroxyproline and the amino sugars in peats vary more than that of the amino compounds. In contrast to inorganic soils, which tend to have a similar amino acid composition, these limited data suggest that the amino acid and amino sugar contents of peats may be characteristic of individual bogs.


1971 ◽  
Vol 121 (2) ◽  
pp. 197-202 ◽  
Author(s):  
M. E. Grant ◽  
F. S. Steven ◽  
D. S. Jackson ◽  
L. B. Sandberg

1. Insoluble elastin has been prepared by several different methods from adult bovine and calf ligamentum nuchae. Highly purified tropoelastin has been prepared from copper-deficient porcine aorta. 2. Amino acid analyses indicated that all preparations, except that obtained from calf ligamentum nuchae by using an EDTA extraction followed by collagenase digestion (preparation E6), were typical of pure elastin having high concentrations of hydrophobic and low concentrations of hydrophilic amino acids. Preparation E6 was found to contain approx. 40% collagen. 3. The determination and composition of the carbohydrates associated with these preparations is reported. With the exception of preparation E6, the insoluble elastins contained only trace amounts of neutral sugars (0.13–0.35%, w/w) and amino sugars (0.01–0.06%, w/w). The porcine tropoelastin contained virtually no carbohydrate. 4. The results suggest that carbohydrate analyses can yield valuable information about the purity of elastin preparations.


1997 ◽  
Vol 34 (9) ◽  
pp. 733-738
Author(s):  
Kiyoshi Nakatsuka ◽  
Hidetoshi Kosaka ◽  
Kiichiro Sekiya ◽  
Shoshi Takamoto ◽  
Toshio Onishi ◽  
...  

1981 ◽  
Vol 60 (2) ◽  
pp. 241-243 ◽  
Author(s):  
Juliet E. Compston ◽  
Anne L. Merrett ◽  
F. G. Hammett ◽  
P. Magill

1. The uptake of either orally administered [3H]vitamin D3 or 25-[3H]hydroxy-vitamin D3 into the chylomicron fraction of plasma was studied in 12 healthy male subjects. 2. The amount of [3H]vitamin D3 in the chylomicron fraction expressed as a percentage of the total plasma radioactivity was higher than that of 25-[3H]hydroxy-vitamin D3. 3. It is suggested that the mechanism of intestinal absorption of vitamin D and 25-hydroxy-vitamin D may differ in man, the absorption of 25-hydroxy-vitamin D possibly being less dependent on bile acids.


1975 ◽  
Vol 33 (1) ◽  
pp. 95-100 ◽  
Author(s):  
D. B. A. Silk ◽  
M. L. Clark ◽  
T. C. Marrs ◽  
Jill M. Addison ◽  
D. Burston ◽  
...  

1. An intestinal perfusion technique was used in six normal human subjects to study absorption of sixteen individual amino acids from an amino acid mixture simulating casein and from an enzymic hydrolysate of casein, prepared for oral administration to these subjects, which consisted of a mixture of oligopeptides and free amino acids.2. Total absorption of α-amino nitrogen was greater from the casein hydrolysate than from the amino acid mixture, and the considerable variation in percentage absorption of individual amino acids from the amino acid mixture was much reduced when the enzymic hydrolysate solution was perfused, as a number of amino acids which were poorly absorbed from the amino acid mixture were absorbed to a greater extent from the casein hydrolysate.3. These findings indicate that after extensive intestinal resections or in malabsorption there might be significant nutritional advantages in the administration of protein hydrolysates rather than amino acid mixtures.


1978 ◽  
Vol 175 (1) ◽  
pp. 333-336 ◽  
Author(s):  
M Vuento ◽  
A Vaheri

Soluble fibronectin of human plasma was specifically dissociated at neutral pH from gelatin-agarose by several cationic amino compounds, notably the polyamines spermine, spermidine and putrescine, the basic amino acid arginine, and amino sugars. The neutral and acidic amino acids and the N-acetylated derivatives of amino sugars tested were ineffective. Gel-filtration experiments demonstrated that [14C]spermidine bound to fibronectin but not to gelatin.


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