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S Sassi

Publications and source records attributed to S Sassi.

10 recordsLinked to original sources
PubMed1991

Structural and functional aspects of the respiratory chain of synaptic and nonsynaptic mitochondria derived from selected brain regions.

Studies on brain mitochondria are complicated by the regional, cellular, and subcellular heterogeneity of the central nervous system. This study was performed using synaptic and nonsynaptic mitochondria obtained from cortex, hippocampus, and striatum of male Sprague-Dawley rats (3 months old). Ubiquinone content, detected by HPLC analysis, was about 1.5 nmol/mg protein with an approximate CoQ9/CoQ10 molecular ratio of 2:1. The activities of several respiratory chain complexes were also studied (succinate-cyt. c reductase, NADH-cyt. c reductase, succinate-DCIP, ubiquinol2-cyt. c reductase, and cytochrome oxidase), and generally found to be higher in mitochondria from cortex than from other regions. Study of the activities of some of these enzymes vs. 1/T (Arrhenius plots) showed a straight line with an activation energy between 7 and 10 kcal/mol in all the three areas considered. Only CoQ2H2-cyt. c reductase activity revealed a biphasic temperature dependence. Also anisotropy (as fluorescence polarization) of the hydrophobic probe DPH showed a deviation from linearity; the break points for both enzymatic activity and anisotropy were found at about 23-24 degrees C.

Animals↗
PubMed1990

Changes in hepatic folylpolyglutamate pattern in phenobarbitone-treated rats.

Folate deficiency is a common unpleasant secondary effect of anticonvulsant therapy. In order to contribute to the knowledge of biochemical mechanisms leading to this condition, the effects of two i.p. high doses of phenobarbitone administered to the rat (acute treatment) on the distribution of hepatic folate derivatives have been studied. A significant decrease of unsubstituted tetrahydro- and dihydropteroylpentaglutamates and 5,10-methylenetetrahydropentaglutamates was observed. The hypothesis that a lower availability of NADPH, which is utilized for hydroxylation reactions in phenobarbitone metabolism, may limit folate reduction is proposed.

Animals↗
PubMed1990

[Compliance and long-term prognosis in hypertensive patients. Case series in a specialized hospital outpatient service].

In this study of ambulatory patients who had their first visit at the hypertension Unit of the Ospedale San Carlo Borromeo in Milan during the years 1979-1983, we report some data regarding compliance and long-term prognosis of mild hypertension. In these 5 years, 445 mild hypertensives (mean DBP: 103.3 +/- 13.2 mmHg) came to our facilities at least once: of these, 57 (12.9%) have been in constant touch with the outpatient clinic until today; 310 (69.6%) have been lost to follow-up after less than 1 year; 78 (17.5%) had an irregular pattern of attendance with a mean length of follow-up of 3.49 +/- 1.8 years. These data indicate a less than ideal compliance especially for patients who were older, smokers, not married and with no previous pharmacological treatment at the first visit. Index of morbidity and mortality for all causes and for cardiovascular disease and blood pressure control were better, although without reaching statistical significance, in the 57 patients with the best compliance. Altogether our data point to a reevaluation of the approach to the problem of mild hypertension through specialised hospital facilities.

Adult↗
PubMed1987

Liver cytosolic protein-bound folates in phenobarbitone-treated rats.

The effect of acute phenobarbitone treatment on the distribution of endogenous bound folates in three specific cytosolic folate-binding proteins (FBP-C), has been studied in rat liver. The bound folate amount shows no difference between treated and control rats. As it is well known that FBP's preferentially bind longer-chain polyglutamates, the content of which is markedly lower in phenobarbitone-treated rat liver, it might be suggested that shorter chain folates also bind to FBP's in these animals.

Animals↗
PubMed1987

Protein bound folates in liver of castrated rats.

The effect of castration and testosterone treatment on the distribution of [3H] radioactive and endogenous bound folates in hepatic cytosolic folate binding proteins (FBP-C) has been studied in rats. The distribution of [3H] radioactive bound folates in these FBP's shows no significant difference in the three experimental group animals. On the contrary a significant decrease in the amount of endogenous bound folates is observed in castrated if compared with control rats, particularly marked for FBP-CI and FBP-CII bound folates. The testosterone treatment of castrated rats partially restores bound folate levels. The decrease of bound folates in castrated rats might be ascribable to a lower availability of longer-chain forms, almost the ones that bind to FBP's; however lower binding protein content and/or lower affinity for ligands cannot be excluded.

Animals↗
PubMedDate not supplied

Pteroylpolyglutamate pool modifications in rat liver after chronic administration of phenobarbitone and valproate.

Chronic intraperitoneal administration of low doses of phenobarbitone and valproate caused different alterations in hepatic percentage distribution of pteroylpolyglutamate derivatives without modification of total folate content. Phenobarbitone treatment caused a significant decrease of the percentage content of reduced unsubstituted and methylene-substituted derivatives, while valproate produced an increase of the percentage content of methenyl-, formyl- and formimino-substituted derivatives and a concomitant percent increase of hexaglutamates. The modified ratios of various pteroylpolyglutamates, both in phenobarbitone- and in valproate-treated animals, probably contribute to influencing the partitioning of the one-carbon pool through the various areas of one-carbon metabolism.

Animals↗
PubMedDate not supplied

[Nifedipine and kidney tubular function].

Aim of the study was to evaluate the influence of nifedipine on the proximal tubular handling of sodium, as judged by variations in the fractional excretion of lithium, which is a simple and reliable indicator of sodium and water reabsorption at this site. Lithium clearance was determined in 17 in-hospital essential hypertensives who took 16 mmol of lithium per os at 10 p.m. The following morning, urine was collected from 7 to 11 a.m. to determine sodium, potassium, lithium and creatinine concentration. The same analyses were performed in a sample of venous blood drawn at midpoint of the urine collection (9 a.m.). The test took place in basal conditions and was repeated 48 hours later when the patients assumed nifedipine, 10 mg per os, at the beginning of the urine collection (7 a.m.). Compared to basal values, nifedipine increased urinary sodium excretion (mean basal: 33.65 +/- 19.44 mEq/4 h; after nifedipine: 46.99 +/- 19.22) with no change in the fractional excretion of lithium. We conclude that the acute natriuretic effect of this calcium antagonist does not depend on variations in proximal tubular handling of sodium.

Female↗
PubMedDate not supplied

[Uremic cholangitis].

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Cholangitis↗