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Biomedical subjects

A Rinaldi

Publications and source records attributed to A Rinaldi.

At least 145 records · Page 8Linked to original sources
PubMed1976

Chromatographic separation of selenohypotaurine, selenotaurine, selenohomohypotaurine and selenohomotaurine.

By either paper or ion-exchange chromatography the two seleninic compounds selenohypotaurine and selenohomohypotaurine, and the two selenonic compounds selenotaurine and selenohomotaurine may be all separated from each other. On paper chromatography seleninic derivatives may be separated from the corresponding sulphinic compounds, while selenonic compounds show RF values similar to those of the corresponding sulphonic derivatives. These two latter types of compounds may be differentiated, however, since selenonic compounds liberate iodine from HI, while sulphonic compounds do not. Also by automated ion-exchange chromatography seleninic derivatives are well separated from the analogous sulphinic compounds, while selenonic compounds are eluted together with the corresponding sulphonic compounds.

Chromatography, Ion Exchange↗
PubMed1976

Oxidation of S-e-carboxymethyl-selenocysteine by L-aminoacid oxidase and by D-aspartate oxidase.

Se-Carboxymethyl-DL-selnocysteine (CMSeC) has been prepared in a pure crystalline form from selenocysteine and monochloracetic acid. It has been shown that CMSeC is a substrate for the L-aminoacid oxidase form snake venom and for the D-aspartate oxidase from beef kidney. Oxygen consumption and ammonia production indicate that only the L or the D form of CMSeC ar acted upon respectively by one or the other of the above enzymes. No noticeable differences were shown in the oxidation rate of CMSeC and S-carboxymethylcysteine, an indication that the substitution of a selenium for a sulfur atom in the molecule does not greatly affect the substrate specificity of the two enzymes. Data have been obtained suggesting that the product of the oxidative deamination of CMSeC Is Se-carboxymethyl-selenopyruvic acid.

Amino Acid Oxidoreductases↗
PubMed1976

Variability of red cell phenotypes between and within individuals in an unbiased sample of 77 heterozygotes for G6PD deficiency in Sardinia.

The distribution of G6PD red blood phenotypes in an unbiased sample of 77 Sardinian certain heterozygotes for the GdMediterranean mutant was found to be skewed in favor of the G6PD (+) cells. Four of these individuals exhibited the normal hemizygous phenotype in all of their cells, but two of them had a mosaic population of G6PD (+) and (-) red blood cells when reexamined after 1 year. These findings suggest that somatic selection may be the main factor determining the phenotype variability of individual somatic cells in highly differentiated tissues of heterozygotes at the G6PD locozygotes for the GdMediterranean mutant should not be used as a criterion for precise estimation of the embryonic or stem tissue cell pool at X inactivation.

Erythrocytes↗
PubMed1976

Hair root versus red cell individual phenotype in Sardinian heterozygotes for G6PD deficiency (Mediterranean type).

G6PD activity was assayed in 20 Sardinian heterozygotes for G6PD deficiency and related to that of LDH and MDH. One of these heterozygotes showed a deficient phenotype in all her follicles, while the remaining 19 had different proportions of deficient, intermediate, and normal follicles. This is in accordance with a previous estimate. Because of the broad fiducial limits at the 5% level and because of some developmental considerations, this value cannot be interpreted as indicative of the number of primordial cells for scalp epidermis at the time of X-chromosome inactivation, as previously stated. The assay of single hair follicles is, however, a very valuable tool for establishing the role of cell selection in the same or in a different tissue, like peripheral blood.

Erythrocytes↗