Kinetics of the colony-forming capacity of bone marrow cells following hydrocortisone administration to mice

A study was made of the dynamics of the colony-forming and migration capacity of the polypotent stem hemopoietic cells of the bone marrow of the F1 (CBA X C57BL) mice after the hydrocortisone administration. The relative count of the stem hemopoietic cells in the bone marrow increased on the 3rd day after the hydrocortisone administration. This elevation was maximal on the 5th day after the hydrocortisone administration. On the 8th day the stem hemopoietic cell count decreased to the normal level.     

Isolation of eukaryotic ribosomal proteins. Purification and characterization of the 40 S ribosomal subunit proteins Sa, Sc, S3a, S3b, S5', S9, S10, S11, S12, S14, S15, S15', S16, S17, S18, S19, S20, S21, S26, S27', and S29

The proteins of the small subunit of rat liver ribosomes were separated into five main groups by stepwise elution from carboxymethylcellulose with LiCl at pH 6.5. Twenty-one proteins (Sa, Sc, S3a, S3b, S5', S9, S10, S11, S12, S14, S15, S15', S16, S17, S18, S19, S20, S21, S26, S27', and S29) were isolated from three groups (A40, C40, and D40) by ion exchange chromatography on DEAE-cellulose, carboxymethylcellulose, and phosphocellulose and by filtration through Sephadex. The amount of protein obtained varied from 0.1 to 11 mg. Six of the proteins (S5', S10, S11, S18, S19, and S27') had no detectable contamination; the impurities in the others were no greater than 9%. The molecular weight of the proteins was estimated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate; the amino acid composition was determined.     

Study of the antibiotic sensitivity of Shigella newcastle isolated in Zaporozhe Province

Sensitivity to antibacterial drugs of 510 strains of Shigella Newcastle isolated from both sporadic patients and cases during the disease outbreaks was studied. The studies revealed a rather high percentage of Shigella Newcastle resistant to the antibiotics widely used in clinical practice. Most of the strains, i.e. 90.5 per cent were resistant to tetracycline and a significant number of the isolates, i.e. 55.6--53.3 per cent were resistant to streptomycin and erythromycin. A statistically reliable predominance of the Shigella resistant to levomycetin and streptomycin in the disease foci was noted as compared to the Shigella isolated from the sporadic patients. Most of the isolates were simultaneously resistant to several antibiotics. Thus, resistance to 2,3--4 and 5--6 antibiotics was found in 28, 54.3 and I.I per cent of the cultures respectively. At the same time almost all Shigella Newcastle strains were sensitive to rifampicin, neomycin and monomycin (aminoglycoside antibiotics), enteroseptol (oxychinoline drug) and furazolidone (nitrofuran drug).     

Vitamin B12-binding substances elaborated by the mucous membrane of the stomach]

Accurate electrocardiographic diagnosis of myocardial ischemia or infarction is difficult in patients with the Wolff-Parkinson-White syndrome; however, myocardial ischemia may also have profound effects on the electrophysiologic characteristics of the bypass tract in these patients. Comparison of studies performed during and two months following an episode of significant myocardial ischemia demonstrated substantial prolongation of the refractoriness of the bypass tract during the period of ischemia. Bypass refractoriness was prolonged by 196 msec, yet atrioventricular nodal refractoriness was not significantly different from normal. These studies, therefore, suggest that, on occasion, the presence of acute myocardial ischemia may, in fact, obscure the electrocardiographic diagnosis of the Wolff-Parkinson-White syndrome.     

Comparative study of cyclophosphamide, 6-mercaptopurine, azathiopurine and methotrexate. Relative effects on the humoral and the cellular immune response in the mouse

The effects of cyclophosphamide, methotrexate, azathioprine and 6-mercaptopurine on the concomitant development of the humoral and the cellular immune responses of mice to a single antigen, the El4 tumour cell, were investigated. The measurements of cellular and humoral immunity were carried out in the same animal using lymphocyte and antibody mediated lysis of the El4 cell, a measurement system independent of underlying anti-inflammatory effects. A regimen of daily cyclophosphamide had a more pronounced suppressive effect on the humoral response than on the cellular response, in agreement with other investigators. A single low dose of cyclophosphamide stimulated the cellular response and suppressed the humoral response. Single or multiple high doses of cyclophosphamide maximally suppressed both the cellular and humoral response. Azathioprine and 6-mercaptopurine, in contrast to the results of other investigations, caused equivalent inhibition of both the humoral and cellular responses and thus lacked selectivity. Methotrexate also provided equivalent inhibition of both the humoral and cellular responses at all dose levels investigated.