A comparative study of the differentiation of dissociated nerve cells under different culture conditions.

In vitro differentiation of chick embryo brain cells was compared under several culture conditions. Morphological observations and acetylcholinesterase histochemical staining revealed that the development was similar in all conditions tested if cells have been derived from 7 days embryos. Considering the cultures from 11 days embryos, the cell dissociation by trypsin and the plastic surface proved to be the most favourable conditions in contrast to mechanical dissection and collagen surface.     

Establishment of serum based essentiall free of proteolytic activity for the culture of mouse pancreatic islets.

The present study demonstrates that a) serum based culture medium degrades 125I inhibits its proteolytic activity leading to the recovery of more insulin secreted by islets cultured in the presence of high glucose concentration alone or with glucagon; c) aprotinin also favoured the accumulation of secreted insulin by protecting the hormone from a residual degradative capacity of the hear treated serum.     

Light stimulated 'shunt-metabolism' succinate-alpha-ketoglutarate-isocitrate cycle and accumulation of citric acid in Aspergillus niger.

Studies with light of the visible range had shown that light plays significant role in the biosynthesis and accumulation of citric acid in Aspergillus niger. Accumulation of 14C-labelled carbon atoms in alpha-ketoglutaric, isocitric, succinic and glycolic acids in the cultures grown under illumination suggest a probable 'shunt-metabolism' leading to the succinate-alpha-ketoglutarate-isocitrate (SKI) cycle. This shunt metabolism minimizes the accumulation of citric acid in cultures due to depletion of intermediates.     

Lipoperoxidation rates and drug-oxidizing enzyme activities in the liver and placenta of some mammal species during the perinatal period.

Lipoperoxidation and drug-metabolizing enzymes were measured in livers and placentas of different mammal species during the perinatal perios. In placentas and fetal livers of rat, rabbit and guinea-pig, cofactor-supported lipoperoxidation was negligible, as were the activities of drug-oxidizing enzymes. Human fetal liver contained an intact drug-oxidizing electron transport chain, and lipoperoxidation activity was accordingly abserved. It is suggested that lesions mediated by lipoperoxidation may be possible in human fetus, but they are less probable in animal fetuses.     

Distribution of type A and B monamine oxidase activities in the central nervous system of rat and chick.

The distribution of type A and B monamine oxidase (MAO) activities in the central nervous system (CNS) of rat and chick was investigated using 5-hydroxytryptamine and beta-phenylethylamine as specific substrates. The distribution of type A MAO was similar to that of type B MAO in rat CNS, but quite different in chick CNS. This may be ascribed to the difference in animal species. The major part of MAO activity in the spinal cord was found to be type A.     

Experimental allergic encephalomyelitis in T-lymphocyte deficient rats.

Thymectomized, lethally irradiated rats reconstituted with syngeneic bone marrow were injected with rat brain in complete Freund adjuvant mixture. Both, they and sham-thymectomized, irradiated and bone marrow protected rats displayed a higher incidence of leg paralysis than normal non-irradiated animals. Thymectomy lowered the incidence of the disease.     

Gastric mucus effusion elicited by oral copper compounds: potential anti-ulcer activity.

In rats, both Cu(I) and Cu(II) show an irritancy profile not shared with Cu degrees or Zn(II) or Ni(II). The gastric response to Cu(II), i.e. copius fluid and mucus secretion, can protect the stomach from the acute ulcerative effects of aspirin or physical stress administered subsequently.