The effects of physostigmine on the oxygen uptake in rat brain tissue

Summary Physostigmine in a dose of 0.1 mg/kg i.v. expressly stimulated the oxygen uptake in the rat cerebral cortex. This effect was blocked by propranolol and seems be mediated by catecholamines. Since atropine also antagonized the stimulant effect of physostigmine, it appears that the action of physostigmine is primarily cholinergic and that the adrenergic effect is a secondary phenomenon. The higher dose of physostigmine (0.4 mg/kg i.v.) caused a depression of rat brain oxygen uptake.This work was supported by a grant from Serbian Republic Scientific Fund (ZMNU SR Srbija), Belgrade (Yugoslavia).The authors wish to acknowledge the skilful technical assistance of Lj. Krsti.     

(−)-Maalian-5-ol,a new enantiomeric sesquiterpenoid from the liverwortPlagiochila ovalifolia

Summary A new enantiomeric sesquiterpene alcohol named (–)-maalian-5-ol was isolated from the liverwort, and the structure and absolute configuration was determined to be the stereostructureI by chemical and spectral evidence.The authors express their gratitude to Dr H. Inoue, National Science Museum, for identification of the liverwort, and Prof. T. Tokoroyama, Osaka City University, for sending of the data of (–)--maaliene and (+)-selina-5,11-diene. Thanks are also due to the Ministry of Education for financial support of this work.     

The effect of acidic polysaccharides and prostaglandin-like substances isolated from Propionibacterium acnes on granulocyte chemotaxis.

Three acidic polysaccharide (AP) fractions and the prostaglandin-like substances (PLS) isolated from P. acnes were investigated regarding their chemotactic activities on polymorphonuclear leukocytes. Both AP's and PLS induced a significant chemotatic response, which suggests their involvement in inflammatory acne vulgaris.     

Effect of insulin on immunological phagocytosis by macrophages.

It was shown that, in physiological concentrations, insulin enhances, in vitro, the immunological phagocytosis of sensitized sheep erythrocytes by cultured mouse peritoneal macrophages. Insulin seems to stimulate macrophage phagocytosis as a cholinomimetic agonist by increasing the intracellular levels of cyclic GMP.     

Alterations of beta-adrenoceptor-density and cAMP-synthesis in rat-erythrocytes after stress erythropoiesis.

During the maturation of red blood cells from rats after stress erythropoiesis, adenyl cyclase activity and beta-adrenoceptor density (pmoles/mg protein) decrease at distinctly different rates suggesting a different turnover of these membrane units.     

Increase in Na+, K+ -ATPase enzyme units in liver and kidneys from essential fatty acid deficient rats.

(3H)-Ouabain binding to liver and kidney preparations was utilized to estimate the number of Na+, K+-ATPase enzyme units in livers and kidneys from rats fed 2% corn oil supplemented or fat-free diets. The specific (3H)-ouabain binding in liver and kidney preparations from fatty acid deficient rats was increased approximately 40%, but the affinity of the binding sites for ouabain (Kd-value) remained unchanged. The increased concentration of Na+, K+-ATPase enzyme units observed in the essential fatty acid deficient rats may contribute to the reduced body fat accumulation and elevated heat production observed in these animals.     

The structure of amoorastatone and the cytotoxic limonoid 12-hydroxyamoorastatin

Summary 2 new limonoid-type terpenes have been isolated from an aqueous extract of seeds produced by the Eastern Himalayan (India) plantAphanamixis grandifolia Bl. By interpreting principally mass spectral and nuclear magnetic resonance data, the structures of 12-hydroxyamoorastatin (2b) and amoorastatone (3) were elucidated. Unequivocal evidence for the 12-hydroxyamoorastatin structural assignment was obtained by chemical conversion to sendanin (4). Amoorastatin derivative2b was found to significantly inhibit growth of the murine P388 lymphocytic leukemia cell lines but amoorastatone in the same system was inactive. In a comparative biological study, sendanin (4) and anthothecol (7) were also found significantly to inhibit growth of the P388 cell line, while rohitukin (8) and limonin (9) were found to be inactive.Part 63 of the series Antineoplastic Agents. For the previous contribution refer to G.R. Pettit, T.S. Krupa and R.M. Reynolds, Int. J. Peptide Protein Res., in preparation. The present investigation was supported in part by Public Health Research Grant No. CA-16049-05 from the National Cancer Institute, the Fannie E. Rippel Foundation, Mrs Mary Dell Pritzlaff, the Spencer T. and Ann W. Olin Foundation, Mr John F. Schmidt, and the Phoenix Coca-Cola Bottling Company.     

A rotating bottle culture method with continuous replacement of the gas phase

Summary A rotator culture method is described which provides a continuous flow of oxygenating gas to cultures in rotating bottles. The system maintains constant O₂ and CO₂ levels in the culture medium throughout the incubation period. It also provides a more stable pH than systems with sealed culture bottles.Acknowledgments. We would like to thank Mr B. Secker, Mr C. Hellon and Mr S. J. Ellis, of the Physiological Laboratory workshop, for constructing the rotator apparatus. We also thank the Medical Research Council, London, for financial support for the project.     

Monolayer cultures of perikarya isolated from postnatal rat cerebellum

Summary Viable cerebellar perikarya of mixed cell type obtained from 7–9-day-old rats were maintained in monolayer culture for up to 12 days. During this time extensive neurite formation and outgrowth occurred. The large majority of the cells developing in culture were tentatively identified as granule neurons. This identification was based on the large number isolated from the starting tissue, and the cells general morphological features in culture such as perikaryal and nuclear size, the bipolar nature of neurite extension, and their migratory behaviour.D.N. Currie was supported by a grant from Hoechst Pharmaceuticals, Ld, U.K.J.C. was supported by an S.R.C. Grant to S.P.R. RoseThe authors would like to thank Kathleen Tear for excellent technical assistance and members of the Brain Research Group for helpful discussions.     

Microwave measurements of the absolute values of absorption by water vapour in the atmosphere

MEASUREMENT of the absolute value of absorption by water vapour at microwave frequencies is difficult because the effect is so small. Far in the wings of the absorption lines, in the so-called 'windows' of the spectrum, it is especially difficult to achieve high accuracy in the free atmosphere. But it is in these windows that the behaviour of the absorption is important from both applied and scientific points of view. Satellite communications, remote sensing of the atmosphere, and radioastronomy, are all influenced by this behaviour. Measurements on an Earth-space path are reported here; the results indicate a nonlinear relationship between absorption and water-vapour content.