Influence of rofenaid-40 feed medication on an experimental Salmonella infection in chickens

Rofenaid-40 administered at 0.02% in feed to chickens experimentally infected with Salmonella typhimurium resulted in less colonization and shedding of S. typhimurium than in unmedicated chickens. The antibacterial sensitivity pattern of S. typhimurium isolated from infected birds had not changed after exposure to Rofenaid for 56 days.

Changes in antigenic nature of lymphocytes caused by common viruses

Healthy human lymphocytes were incubated in the presence of influenza A2/Singapore/57, herpes simplex type 1, or adenovirus type 2. After two days the cultures were inactivated by irradiation. Fresh lymphocytes taken from the same donor were then found to react to the virus-treated cells in short-term cultures. We suggest that this reactivity is due to a change in the surface characteristics of the lymphocytes brought about by the presence of the virus. This may account for anomalous reactions in mixed lymphocyte cultures, and a similar effect in vivo might cause accelerated graft rejection.

Chronic repetitive suppurations of skin associated with a serum factor affecting bactericidal capacity of polymorphonuclear leukocytes

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The mitogenic effects of isologous nuclear material

The nuclear material from human lymphocytes stimulated with phytohaemagglutinin (PHA) will produce a marked increase of DNA synthesis in unstimulated isologous lymphocytes which is far in excess of the normal response to PHA by the same lymphocytes. It is postulated that release of nuclear complexes from a few lymphocytes transformed in response to a specific stimulus is responsible for the transformation produced in surrounding lymphocytes which are non-responsive to the initial antigenic challenge.

Loss of proteinpolysaccharides at sites where bone mineralization is initiated

In both ground sections and demineralized frozen sections of the rat tibial cortex, osteoid but not mature bone matrix stained for proteinpolysaccharides with the Alcian Blue and toluidine blue techniques. The loss of proteinpolysaccharide staining occurred precisely at the mineralizing front, which was identified by in vivo lead or procion markers, not only in normal animals but also in animals in which osteoid width was either increasing or decreasing. In vitro, both proteases and saccharidases abolished proteinpolysaccharide staining of osteoid. Critical electrolyte concentration and other procedures indicated that the major acid polysaccharide component in osteoid is chondroitin sulfate. Consistent with these findings, electron microprobe analyses revealed that sulfur concentration was high in osteoid but dropped abruptly as calcium concentration increased at the mineralizing front. The precise synchronization between loss of proteinpolysaccharides and onset of mineralization under various experimental conditions provides strong indirect evidence that the loss of these macromolecules is somehow involved in initiation of mineralization in bone.

Inhibition by lymphocyte nuclei of DNA and RNA synthesis in stimulated lymphocytes and leukaemic cells

Chromatin material in the form of intact bald lymphocyte nuclei was found to inhibit DNA and RNA synthesis in isologous cells previously stimulated with Phytohaemagglutinin (PHA) especially in 6 day cultures. These bald nuclear complexes produced a reduction in the DNA and RNA synthesis occurring in allogenic leukaemic cells.

Composition of the cell wall of Pityrosporum ovale (Bizzozero) Castellani and Chalmers

Fractions of the cell wall of the yeast, Pityrosporum ovale, were analyzed for neutral sugars, nitrogen, protein, hexosamines, cysteine + cystine, lipids, and ash as affected by age of cells and degree of breakage of cells. Neither the age of cells nor the degree of breakage influenced the composition of the fractions very much. The results indicate that the composition of the wall of P. ovale is substantially different from that of Saccharomyces cerevisiae, being higher in lipid, protein, and glucosamine. The polymerized N-acetyl-glucosamine in the wall seems to be present in a non-crystalline form. These results are consistent with known structural differences between the walls of the two genera.

The influence of pH on intestinal metabolism and transfer in vitro

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