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Biomedical subjects

F Fraschini

Publications and source records attributed to F Fraschini.

At least 181 records · Page 10Linked to original sources
PubMed1981

A superfusion method for the study of secretion activity of isolated cerebral and endocrine tissues.

This paper describes a new kind of superfusion technique that allows for the maintenance of small fragments of nervous tissue, such as of the hypothalamus and the pituitary and pineal glands, suspended in a very small perfusion chamber with a continuous flow of medium that reproduces "in vivo" conditions. Easy reproducibility; continuous flow of medium, which avoids short feedback phenomena; controlled conditions that are very close to those "in vivo" and the possibility of sequential treatments for the study of the dynamics of hormone release are some of the advantages of this method.

Animals↗
PubMed1981

Bactericidal activity of erythromycin in the respiratory system.

In vivo and in vitro studies were carried out to assess tha levels in bronchial mucus of ampicillin, amoxycillin, bacampicillin, cefotaxime and erythromycin, and to compare their minimum bactericidal concentrations and killing rate against hospital strains of Staphylococcus aureus, Streptococcus pyogenes and Haemophilus influenzae. Both the percentage ratios of serum/mucus concentration peaks and of serum/mucus area under the concentration time curve values were higher for erythromycin than for the other antibiotics. Determination of the minimum bactericidal concentrations showed that the bacterial strains were sensitive to small quantities of erythromycin, and the time necessary to sterilize inocula varied from 4 to 16 hours.

Amoxicillin↗
PubMed1981

Changes in th circadian rhythm of ornithine decarboxylase in rat liver during chemical hepatocarcinogenesis.

The chronobiology of ornithine decarboxylase (ODC) activity in livers was investigated in noninbred Sprague-Dawley rats fed for 5 months with a basal diet or diets with 3-methyl-4'-(dimethylamino)azobenzene (3-Me-DAB) that were oncogenic or caused bile duct hyperplasia (1-naphthylisothiocyanate) (NIT). After a transient disappearance of the ODC circadian rhythm during month 1 on the oncogenic diet, this rhythm in the livers of the rats was reestablished at 60 and 90 days and then disappeared for the next 2 months. When present, the ODC rhythm in 3-Me-DAB-treated rats had the same daily temporal pattern as that of the controls. In the livers of rats treated with NIT, the ODC circadian rhythm was never detectable, even after only 1 month of feeding. Generally, the 3-Me-DAB feeding induced higher levels of ODC activity than did the NIT feeding. The alternation of the appearance and the disappearance of ODC circadian rhythm might reflect changes in the cell population during neoplastic transformation. Te chronobiologic differences in ODC rhythm between the group fed 3-Me-DAB and the group fed NIT could be related to the different types of proliferating cells involved in the hepatic responses to the two drugs.

1-Naphthylisothiocyanate↗
PubMed1981

Clinical pharmacokinetic evaluation of bacampicillin.

Bacampicillin is a recently synthesized prodrug of ampicillin. It differs from ampicillin in having an ethoxycarbonyloxyethyl group attached to the carboxyl group in C3 of the penicillin nucleus, thus forming an ester with higher bioavailability than ampicillin. The present study was carried out in 30 patients suffering from acute exacerbations of chronic bronchitis. Bacampicillin was administered orally according to the following outline: Group A--800 mg, group B--1,200 mg, and group C--1,800 mg. The peak mean serum levels were 9.50, 12.07, and 15.83 micrograms/ml, respectively, and were reached in one hour with all doses. The peak mean bronchial mucus levels were 0.49, 0.62, and 0.95 micrograms/ml, respectively, and were achieved in four hours with all doses. During the eight hours after administration of the antibiotic, 71%, 68%, and 73% of the administered doses were excreted in the urine. Blood levels versus time curve were interpreted in terms of a one-compartment open model. Bronchial mucus and serum peaks were in good correlation with progressive doses.

Ampicillin↗
PubMed1980

Pineal gland and polyamines.

The activity of ornithine decarboxylase was assayed in several organs (thymus, testes, prostate gland, liver, kidneys, adenohypophysis, anterior hypothalamus, and adrenals) taken from adult male rats killed at seven day interval up to six weeks after pinealectomy. The absence of the pineal gland particularly influences the ornithine decarboxylase activity in the thymus, in which the level of the enzyme is decreased irreversibly by the fourth week after the operation. In other organs the ornithine decarboxylase activity was often significantly different from that of corresponding shampinealectomized controls at various weeks after the surgical removal of the gland. Moreover, these differences between operated and sham-operated animals are sometimes positive, sometimes negative. Thus, the polyamine biosynthetic pathway in different organs appears to be regulated, directly or indirectly, by a new neuroendocrine centre, the pineal gland, and this pineal gland has thus been shown to be active in adult life in correlating endocrine-enzymatic functions.

Adrenal Glands↗
PubMed1979

Endocrine regulation of thymic biosynthetic polyamine decarboxylases in adult rat.

The activities of ornithine and S-adenosyl-L-methionine decarboxylase were assayed in the thymuses of adult rats killed at 7-day intervals up to 6 wk after either pinealectomy or sham pinealectomy. The absence of the pineal gland markedly influenced the ornithine decarboxylase activity in the thymus, in which the level of the enzyme was decreased permanently by the 4th wk after the operation (P less than 0.05). The time course of the changes in S-adenosyl-L-methionine decarboxylase activity in the thymus during the entire period investigated was also significantly (P less than 0.05) modified by pinealectomy but did not show any stable trend. Adrenalectomy significantly raised (P less than 0.001) for ornithine decarboxylase; P less than 0.01 for S-adenosyl-L-methionine decarboxylase) the basal levels of the thymic biosynthetic polyamine decarboxylases. A pharmacological dose of corticosterone or cortisol produced a rapid and significant decrease in ornithine and S-adenosyl-L-methionine decarboxylase activities (P less than 0.02) in the thymus, whereas the injection of either D-aldosterone or ACTH was ineffective. Therefore, the thymic biosynthetic polyamine decarboxylases that in this organ are known to be located only in the lymphocytes appear to be regulated in opposing ways by the pineal gland and by the adrenal cortex.

Adenosylmethionine Decarboxylase↗
PubMed1979

Bactericidal action of an average dose of erythromycin in the bronchi.

A study was carried out to establish whether erythromycin stearate was bacteriostatic or bactericidal at the concentrations reached in the bronchial secretion. Twenty-two patients suffering from an acute attack of chronic bronchitis, sustained by streptococci, diplococci, staphylococci or H. influenzae sensitive to erythromycin, were treated with 1500 mg erythromycin per day until symptoms regressed, usually within 3 to 5 days. The results showed that after treatment there was a dramatic reduction in the number of bacterial colonies cultured from the bronchial secretion and marked changes in bacterial morphology were seen using electron microscopy. Further evidence of bactericidal activity was provided by the rapid clinical response of the patients.

Aged↗