[Mechanism of lipid inhibitory effect on intestinal fucosyl-transferase in the rat]

High-fat diets decrease microsomic and soluble fucosyl-transferase activities in rat intestinal mucosa. This inhibition is not due to qualitative (pHi) or quantitative (relative activities) changes ion three isoenzymes, nor is it caused by alterations in the kinetic behaviour of these enzymes (Km, V). It is also not due to a direct effect of the fatty acids on the enzyme activities. It seems reasonable to suggest that a decreased biosynthesis of the fucosyl-transferase occurs as a result of the high-fat diets.

Biosynthesis of glycoproteins in the intestinal mucosa. II. Influence of diets

To determine the effect of diets on the biosynthesis of glycoproteins in the intestinal mucosa, male Sprague-Dawley rats were fed, ad libitum, high-carbohydrate high-fat and high-protein diets. In in vivo methodology, the animals from each dietary group received an intraperitoneal injection of [14C]-fucose, or [14C]-galactose or [14C]-glucosamine. Incorporated radioactivity was detected in the different subcellular fractions. In in vitro methodology, five glycosyl-transferases were studied on microsomes and cell sap. In vivo, only the high-fat diet induces a decrease in the incorporation of [14C]-glucosamine in the macromolecules. In vitro, only the fucosyl-transferase activity is modified by several diets: as compared with an increase in the activity of the control with the age of the animals, high-protein diet induces a slight activation after 2 weeks of diet, while high-carbohydrate and particularly high-fat diets inhibit the enzyme activity. The inhibition is the same when high-fat diet consists of either oil mixture or triolein or oleic acid or linoleic acid and becomes significant with a supplementation rate of 10%.

Common exposure outbreak of gastroenteritis due to type 2 rotavirus with high secondary attack rate within families

A sharp outbreak of gastroenteritis associated with human rotavirus type 2 involved not only all of nine infants and young children in a playgroup but also seven of 10 parents and grandparents studied. The source of the outbreak appeared to be two non-playgroup siblings. Six of 11 individuals studied shed human rotavirus type 2, and each of seven from whom paired sera were obtained developed a type 2 sero-response. Overall, evidence of infection with rotavirus type 2 was demonstrated in 10 of 11 individuals by detection of virus in stools and/or a serologic response in an enzyme-linked immunosorbent assay.

Study of nuclear mannosyl-transferase: lipids intermediates

Mannosyl-transferase of rat liver nuclei catalyzed the transfer of mannose, from GDP-mannose, to endogeneous lipids and proteins. Two solubility-different glycolipids were characterized: a mannosyl-phosphoryl-dolichol and an oligosaccharide-lipid. The labeling of the two lipids was consistent with a role in mannose transfer to nuclear glycoproteins, but not according to the Lennarz' scheme.

[Spontaneous pneumomediastinum in adults. 10 cases (author's transl)]

Since it is relatively rare, spontaneous pneumomediastinum is often little known to clinicians. Making the diagnosis, however, presents no problem if the three essential signs are present, that is to say: -subcutaneous emphysema of the base of the neck (7 cases), -Hamman's sign, (6 cases), -a paramediastinal air shadow on chest roentgenograms, (8 cases). The condition is brought about by rupture of perivascular alveoli resulting in the migration of air along the pulmonary vessels. The principal advantage of making the diagnosis is that it enables one to eliminate other pain-causing thoracic syndromes, especially myocardial infarction, pulmonary embolus and acute pericarditis. The clinical course is usually benign necessitating no treatment.

[Stimulation of pituitary gonadotropin secretion after castration in rainbow trout: variation of the response during the reproductive cycle]

Bilateral castration of male rainbow Trout resulted in increased levels of circulating gonadotropin, as measured by radioimmunoassay, but the response varied depending on the season. In early May the increase was 12 ng/ml after 30 days, when compared to the intact control but later in the month at the time when a peak of gonadotropin level is observed in normal fish, the increase was 25 ng/ml after 13 days. At the beginning of August, when spermatogenesis commences, the increase was 9 ng/ml after 12 days. In September, when spermatogenesis is ending, an increase of 20 ng/ml was found after 7 days, but only 50% of the animals responded. In December, during spermiation, an increase of 90 ng/ml was found after 7 days.

Glycoprotein biosynthesis in splenic cells. Purification of a microsomal galactosyl-transferase

One part of the microsomal galactosyl-transferase activity of splenic cells of rats can by solubilized by the action of Triton X-100 and Tween 20. Its purification on a Sephadex G-200 column and by electrophoresis on a polyacrylamide gel leads to a solution of high specific enzymic activity.

[Phentolamine in treatment of acute left ventricular insufficiancies]

Phentolamine (Regitine) at the dose of 0.3 mg/mn behaves as an arterial and, above all venous, vasodilatator agent, resulting in a marked and early lowering of the pulmonary pressures in acute oedema of the lung and in cardiac asthma. It was used alone in 47 attacks of acute severe left ventricular failure with very favourable results in 43 cases, as proved by the rapid improvement of the haemodynamic status and of the aicd-base balance. Under strict observation, tolerance has been excellent. This therapeutic method seems of great interest in the cases of acute pulmonary oedema with a maintained blood pressure level, and in the forms with severe arterial hypertension which might tolerate larger doses.

[Study of the concentration of glycosaminoglycans in cartilage from normal and osteoarthritic femoral head]

The biochemical composition of cartilage was studied in relation to the site of the sample and the age on 20 normal femoral heads and in relation to the histological appearance of the tissues on 34 arthrosic femoral heads. The collagen and glycosaminoglycan content of normal cartilage is identical in the four poles of the femoral head but becomes reduced with age. The chondroitin sulphate content falls slightly but slowly during ageing. In arthrosis, the glycosaminogylcan content is reduced when the cartilage is eroded and remains roughly normal when the cartilage is macroscopically normal or osteophytic. The cartilage of the osteophyte differs, however, radically from normal articular cartilage by a very high water content and by the presence of glycosaminoglycans which are mainly dialysiable. Similar modifications, that are less marked, occur in the macroscopically normal cartilage of the arthrosic femoral head and suggest the role of a disorder of glycosaminoglycan synthesis in the etiology of certain cases of arthrosis.