Characterization of cytoplasmic arginine-rich basic protein of Guerin epithelioma

Summary Arginine-rich basic protein from cytoplasma of Guerin epitheliomas has been isolated and characterized. It contains five amino acids: arginine, lysine, glycine, alanine and glutamic acid which make together 74 per cent of all amino acid residues. The protein has a cationic character with an isoelectric point of 8.2. No carbohydrate component was found in this protein. The significance of arginine-rich basic protein in the cytoplasma of Guerin epithelioma is discussed briefly.     

Enhanced susceptibility of DNA-synthesizing nuclei of epithelial cells of the intestine to acid hydrolysis

Summary Albino mice were injected intraperitoneally with tritiated thymidine and killed 1/2 and 30 h later. Pieces of ileum were excised and fixed. Tissue sections were hydrolyzed with 5 N HCl at 21° C for 1/2, 1, 2, 3, 4 and 6 h, some sections remained unhydrolyzed. Both the hydrolyzed and nonhydrolyzed sections were autoradiographed. Grain counts per labelled nucleus of either cryptal (DNA-synthesizing) or villous (DNA-nonsynthesizing) cells nonhydrolyzed and hydrolyzed for various time intervals were recorded.The results indicate, that the grain count of nonhydrolyzed, labelled nuclei from cryptal cells was by 1.49 higher than that of villous cells demonstrating the rate of grain counts diminution caused by cell divisions.Hydrolysis caused a diminution of grain count of cryptal cells by approximately 15% higher than that of the grain count of villous cells.Financial support was partially obtained from grant MR II.1.We wish to thank Dr. W. Sawicki for his supervision, advice and encouragement throughout this work     

Isoelectric focusing patterns of staphylococcal exfoliative toxin

Multiple components in two antigenic variants of staphylococcal exfoliative toxin were demonstrated by isoelectric focusing in polyacrylamide gel. The main components had an isoionic point of pH=7.0 while other components ranged from pI=4.5 to pI=8.5. Each individual component was shown to possess full biologic and serologic activity after focusing. Isoelectric focusing in the presence of 8 M urea also showed microheterogeneity in exfoliative toxin preparations. The various components appear to be reversible conformers, possibly raised by exposure to the ph gradient of the ampholines.     

Biochemical changes of rat brain membranes with aging

Modification of membrane composition and enzymatic activities both in total brain homogenate and purified synaptic plasma membrane of 3 and 24 month old rats has been investigated. Protein, cholesterol and phospholipid content and (Na+, K+)ATPase and 2',3' cyclic nucleotide phosphohydrolase activities were determined. The major changes occurred in the whole homogenate where a general increase in total protein and cholesterol content with age and a significant increase of the cholesterol/phospholipids molar ratio has been detected. In S.P.M. aging process induced a decrease of protein, cholesterol and phospholipids content associated with an increased membrane viscosity and a decrease of delta E. These data are consistent with a change in the structural organization and in the distribution pattern of different cell population in the aging brain. A possible artifactual effect of freezing on the reported parameter is also discussed.     

Lathyrus nissolia subsp.futakii subsp. nova in der Tschechoslowakei

A new subspecies,Lathyrus nissolia L. subsp.futakii Chrtková subsp. nova is described from East Slovakia. The diacritical characters are: high and rich branched stems, 50–110 cm long and larger, 10–12 mm long, bright orange-red flowers. It differs also in ecology, growing in wet lowland forests with the level of the ground water up to 15 cm over the earth also in summer.     

Quantitative changes in potassium,sodium, and calcium in the submaxillary salivary gland and blood serum of rats exposed to 2880-MHz microwave radiation

Na⁺, K⁺, and Ca²⁺ concentrations in the blood serum and submaxillary salivary gland (SSG) were investigated in adult, male rats exposed to 2880-MHz microwaves modulated with 1.5-μs pulses at a pulse repetition rate of 1000 Hz or in a hyperthermal environment. Rats were exposed, one at a time, for 30 min to microwaves producing a specific absorption rate (SAR) of: 4.2, 6.3,6.8,8.4, 10.8, or 12.6 W/kg, or were sham exposed under similar environmental conditions. In a second series, one group of rats was exposed singly for 15, 30, or 60 min to microwaves producing an SAR of 9.5 W/kg and other rats were exposed for similar periods at 40 °C; and 10 rats were sham exposed. Flame photometric analysis indicated that the thresholds of microwave radiation required to induce a change in Na⁺, K⁺, and Ca²⁺ concentrations in the salivary glands are 6.8, 6.8, and 6.3 W/kg, respectively. The directions of Na⁺, K⁺, and Ca²⁺ ion shifts in exposed rats' salivary glands are similar, whether affected by microwaves or hyperthermia. Greater changes in Na⁺ and K⁺ concentrations in SSG of rats exposed to microwaves for 15 and 30 min were found than in those exposed at 40 °C. On the other hand, exposure to hyperthermia at 40 °C or to microwaves for 1 h caused Na⁺ concentration to be increased by 68.7 and 59.5% and K⁺ concentration to be decreased by 29.6 and 21.7%, respectively.