PubMed Health⌕ Search

Biomedical subjects

F Marchini

Publications and source records attributed to F Marchini.

53 records · Page 3Linked to original sources
PubMed1986

A critical evaluation of the urinary inhibiting activity in idiopathic calcium oxalate nephrolithiasis.

In order to obtain new insights into the relevance of inhibitors in whole urine by focusing on their reciprocal interactions, a statistical approach was followed in 35 controls and 27 calcium oxalate (CaOx) recurrent idiopathic stone formers. The inhibiting activity of CaOx crystal growth and the most widely accepted inhibitors (glycosaminoglycans, citrate, magnesium, pyrophosphate), stone constituents (calcium, oxalate, phosphate, urate) and other normal urinary substances were evaluated. It was seen that the inhibitors played a very small role in total inhibiting activity. On the other hand, considering other normal urinary constituents, almost all the inhibiting power of urine on crystal growth could be explained.

Adult↗
PubMed1984

Raised transmembrane oxalate flux in red blood cells in idiopathic calcium oxalate nephrolithiasis.

Red-blood-cell transmembrane oxalate flux was measured in a group of patients with idiopathic calcium oxalate nephrolithiasis and in normal controls. The mean transmembrane oxalate flux rate was significantly higher in stone-forming patients than in controls (0.93 +/- SD 0.31/min vs 0.29 +/- 0.11/min). 80% of stone-forming patients showed raised (greater than 2SD above the mean in controls) transmembrane oxalate flux. Anomalous cellular oxalate transport may be an important pathogenetic factor in calcium oxalate nephrolithiasis.

Adult↗
PubMed1984

Beta 1 - beta 2 blocking activity of propranolol and metoprolol in the unanaesthetized genetically hypertensive and normotensive rat.

The beta-antagonistic activity of propranolol and metoprolol has been evaluated, in terms of inhibition of isoproterenol effects, "in vitro" (isolated right atria and tracheae) and "in vivo" in unanaesthetized normotensive and spontaneously hypertensive rats (SHR). Metoprolol resulted 13 - 6.4 - 14 times more cardioselective than propranolol in the three aforementioned experimental models, respectively. SHR, because of its decreased baroceptor sensitivity to trigger the tachycardic reflex, proves a good model for the evaluation of beta 1 antagonistic activity of "cardioselective" beta- blockers, which could be underevaluated in the normotensive rat. Moreover, the agonistic activity of isoproterenol has been compared in normo and hypertensive rats in order to ascertain whether the different number of beta 1 receptors in the two strains could influence the biological response to their stimulation and/or or blockade.

Animals↗
PubMed1984

[Role of Tamm-Horsfall mucoprotein in calcium oxalate lithogenesis].

Tamm-Horsfall (TH) mucoprotein has been suggested to play a lithogenetic role in calcium-oxalate nephrolithiasis. However it is still debated whether it promotes or inhibits crystal growth and aggregation. To make clear the role played by this mucoprotein, we have carried out the following experiments: 1) the urinary excretion of TH has been evaluated by radial immunodiffusion in 27 recurrent idiopathic CaOx stone formers and in 35 controls; 2) in a metastable solution of CaOx the effect of TH addition on crystal growth has been monitored; 3) in whole urine the effect of TH addition on crystal aggregation has been assayed by an aggregometer. Urinary excretion of TH is significantly lower in stone formers. TH does not seem to promote crystal growth, while it is effective on crystal aggregation. These data seem to suggest that the reduced excretion of TH in nephrolithiasis may be a lithogenic risk factor.

Calcium Oxalate↗
PubMed1984

[Abnormalities in the erythrocyte membrane transport of oxalate in calcium oxalate lithogenesis].

The high incidence of a family history and the observation of abnormally high intestinal absorption and urinary excretion of oxalate suggest to consider idiopathic calcium oxalate nephrolithiasis as a metabolic disease characterized by a disorder in oxalate transport. To test this hypothesis, the flux of 14C Oxalate through the membrane of red blood cells was investigated in 24 calcium oxalate stone formers; 18 of the 24 "idiopathic" calcium oxalate stone formers showed an increased oxalate self exchange (75%). Our data seem to support the possibility that "idiopathic" calcium oxalate nephrolithiasis may be considered as a metabolic disease marked by a defect in transmembrane transport of oxalate.

Adult↗
PubMedDate not supplied

The role of dopaminergic agonists in congestive heart failure.

Congestive Heart Failure is a clinical syndrome characterised by myocardial dysfunction and sympathetic activation. Plasma norepinephrine (NE) levels have been related to the poorest survival. Large-scale clinical trials have proved the clinical benefits of Angiotensin Converting Enzyme inhibitors in reducing the risk of death and hospitalisation. However, mortality remains high in the treated group underlining the need to explore new therapeutic approaches. Specific activation of peripheral dopamine receptors exerts profound hemodynamic effects and neurohormonal control such as peripheral and renal vasodilation, diuresis and natriuresis and inhibition of NE release. Z1046, a mixed D1/D2-like agonist, reduces peripheral and renal vascular resistance increasing renal blood flow. In anaesthetised dogs the compound strongly reduces plasma NE without increasing plasma renin activity and plasma aldosterone. The inhibition of NE could be the basis of Z1046 potent cardioprotective effect observed in a dog model of myocardial ischemia and reperfusion, in which the severity of ventricular arrhythmias was markedly reduced, resulting in higher survival. These findings suggest that chronic oral treatment with specific dopaminergic agonists is able to alleviate the hemodynamic burden on the myocardium, and to suppress the sympatho-adrenal activity.

Animals↗