Magnetic properties and electronic structures of R-Ni-B compounds where R is a heavy rare earth.

Magnetic measurements were performed in the temperature range 4.2-300 K and fields up to 70 kOe on R(3)Ni(7)B(2) compounds with R = Gd, Tb, Dy, Ho, Er. The Curie temperatures decrease from 38.5 K (Gd) to 7 K (Er). Band structure calculations show that nickel, at 0 K, has a very small magnetic polarization, oriented antiparallel to the rare-earth moment. The XPS measurements suggest the presence of unoccupied Ni3d states. The reciprocal susceptibilities follow a Curie-Weiss type behaviour. Effective nickel moments of 1.33 ± 0.25 µ(B) were determined. The magnetic behaviour of nickel is analysed in models which take into account electron correlation effects in d bands.

Effects of Corylus avellana in acetaminophen and CCl4 induced toxicosis.

Our study investigated the effects of Corylus avellana extract on acetaminophen and carbon tetrachloride intoxicated liver of young rats. Hepatocytolysis was determined by measuring the level of serum transaminases (GPT and GOT), steatosis by Sudan black staining, histological structures by hamatoxylineosin staining and the activity of enzymes such as SDH, GtDH, G-6-Pase and ATPase. Comparatively, the most serious lesions appeared in CCl4 intoxication. Corylus avellana extract had some beneficial effects in CCl4 toxicosis: it reduced hepatocytolysis as well as histological lesions and returned the activity of some enzymes to normal values.

Growth inhibition of experimental glioma by human interferon-beta superinduced by cationic liposomes entrapping polyinosilic:polycytidilic acid.

Intracellular production of human interferon-beta (HuIFN-beta) was enhanced in three glioma cell lines (U251-MG, U251-SP, and U251-NN) using modified superinduction with cationic liposomes containing polyinosilic:polycytidilic acid (polyI:polyC), initially given with cycloheximide, to decrease the toxicity due to polyI:polyC. Modified superinduction had a significantly (p < 0.02-0.0001) greater inhibitory effect on all three glioma cell lines, and less toxicity than superinduction. A pilot trial in experimental gliomas implanted into nude mice was also performed. Superinduction including intratumoral injection of cationic liposomes containing polyI:polyC resulted in growth inhibition of U251-NN tumors and eradication of U251-SP tumors. Weight gain in mice was not inhibited by modified superinduction. Cationic liposomes decreased drug toxicity, and may help to target tumor cells in the modified superinduction of endogenous HuIFN-beta production.

Morphological and enzymological changes of small intestine of adult female rats and youngs born from madiol-treated pregnant rats.

Some histological and histoenzymological changes of the small intestine of adult female Wistar rats treated with Madiol were studied. The steroid did not influence the tissular aspect, but obviously stimulatory effects on protein and enzyme reactions were induced. Similar Madiol-action on the small intestine of 21-day-old young rats was observed when the steroid was administered during pregnancy to their mothers, suggesting influences on the embryonic development.

Histoenzymological and ultrastructural changes in rats following the administration of aminopyrine and nitrite (nitrosoaminopyrine).

Wistar male rats weighing 230-250 g were given 10 mg aminopyrine and 10 mg sodium nitrite daily, by gavage, for 20 days. The histological changes in the liver are of the cirrhotic type. The ultrastructural changes are dependent on the hepatocyte position in the hepatic structural changes are dependent on the hepatocyte position in the hepatic lobule. Thus, in the perilobular area one finds hepatocytes with an increased volume and hypertrophic nuclei and nucleoli, mitochondriae swollen with dispersed cristae, decrease of the number of free ribosomes, glycogen depletion, GER decrease and SER development. In the centrolobular area, the most injured, there are necrotic changes with numerous cytolysosomal formations. The histoenzymological results show a decrease of LDH, SDH, CyOx, GtDH, StDH, ATP-ase and G6P activities. The activity of Ac.P on the contrary, is greater in the intoxicated rats, which correlates with the above-mentioned necrobiosis processes.

Histoenzymological and biochemical changes in the liver of adult female rats and of youngs born from Madiol-treated pregnant rats.

The effect of a 30-day treatment with Madiol was studied on the activity of some enzymes, nucleic acids, protein and glycogen content of the liver of adult female rats and youngs born from mothers treated during pregnancy. Madiol caused a significant increase in SDH and Atp-ase activity, and decreased glycogen and acid phosphatase.