Biomedical subjects

R M Jacobs

Publications and source records attributed to R M Jacobs.

At least 109 records · Page 6Linked to original sources

PubMed1980

Serum electrophoresis and immunoglobulin concentrations in cows with lymphoma.

Changes in the serum electrophoretic patterns and immunoglobulin (Ig) concentrations were examined in cows with lymphoma, in clinically normal cows, and in cows with various inflammatory conditions. Cows with lymphoma had moderately increased concentrations of alpha 2-globulin which were significantly different from concentrations in normal animals (P less than or equal to 0.01) and in animals with inflammatory conditions (P less than or equal to 0.05). This was possibly due to the increase in acute-phase reactant proteins which occurs with inflammation and neoplasia; however, there was the suggestion that these alpha 2-globulins may be qualitatively different in animals with neoplasia. beta 2-Globulins were significantly (P less than or equal to 0.01) decreased in cows with lymphoma, and this was attributed to lower concentrations of Ig observed in this group. All Ig classes, except IgA, were decreased in cows with lymphoma, but the greatest decrease was observed in the IgM class.

Animals↗

PubMed1980

Inhibition of lymphocyte blastogenesis by sera from cows with lymphoma.

The sera from cows with lymphoma inhibit the blastogenesis of normal lymphocytes. The inhibitory sera were partially characterized. Twenty of 34 sera from cows with lymphoma caused inhibition, whereas 3 of 25 sera from healthy animals were inhibitory. Sera from 15 cows with various inflammatory conditions did not cause inhibition. Seventy-four cows were tested for responsiveness to phytohemagglutinin, and of this group, the stimulation indices of 25 animals which had antibody to the bovine leukemia virus did not differ from the remainder of the group. The inhibitory substance: (a) was heat stable at 56 C for 30 minutes, (b) was not overcome by the addition of phytohemagglutinin, (c) was active in a manner that was proportional to the concentration of serum in the culture media, (d) was not lymphocytotoxic at a concentration which was profoundly inhibitory to blastogenesis, (e) was found in the first peak eluted from a Sephadex G-200 column, (f) was nonspecifically active because it inhibited the blastogenesis of a panel of lymphocytes from healthy animals, (g) was present in 59% of cows with lymphoma in the terminal stages of disease, (h) was rarely present in healthy cows or cows with inflammatory conditions, and (i) was not associated with bovine leukemia virus infection in the absence of tumor development.

Animals↗

PubMed1979

Effects of nutritional factors on metabolism of dietary cadmium at levels similar to those of man.

Several nutrients are known to affect cadmium toxicity, but little is known about the effect of dietary nutrient levels on absorption and tissue retention of cadmium at low dietary levels, similar to those of man. Feeding gradedlevels of zinc in a casein-gelatin diet to young Japanese quail with 109Cd (as the chloride) and 0.062 ppm added cadmium decreased the cadmium concentrations in the proventriculus-ventriculus, duodenum, jejunum-ileum, and the liver, but not in the kidney. Zinc also affected some zinc, iron, manganese, and copper tissue levels. Different tissue concentration patterns of cadmium and essential minerals were obtained with two purified control diets, one based on casein-gelatin and the other on soy isolate as the principal protein sources. The data show that relatively small dietary changes can markedly affect tissue levels of cadmium and that a low intake of zinc may increase the risk to dietary cadmium exposure. The complexity of the nutrient interrelationships and their effects on cadmium require further study to define mechanisms, which may be similar to those produced by low cadmium intakes in man.

Animal Nutritional Physiological Phenomena↗

PubMed1979