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C Santini

Publications and source records attributed to C Santini.

64 records · Page 4Linked to original sources

Aldosterone related blood volume expansion in cirrhosis before and during the early phase of ascites formation.

Thirty-seven patients with liver cirrhosis (16 without ascites: group 1; 21 with untreated ascites at the first onset: group 2) were studied during controlled sodium intake (40 mmol/day). Renal plasma flow, glomerular filtration rate, urinary sodium excretion, plasma sodium and potassium, plasma renin activity, plasma aldosterone concentration, blood volume, and arterial pressure were evaluated. All the patients had normal renal perfusion, plasma sodium and potassium, and arterial pressure. Mean plasma renin activity and plasma aldosterone concentration were significantly depressed in group 1 (p less than 0.001, p less than 0.005 respectively) compared with 21 normal controls in identical experimental conditions. This was possibly a consequence of expanded blood volume (p less than 0.001 compared with controls) which was directly correlated with plasma aldosterone concentration (p less than 0.001). In group 2 plasma renin activity and plasma aldosterone concentration were normal in over 50% of cases. Blood volume was lower than in group 1 (p less than 0.002), but again related to plasma aldosterone concentration (p less than 0.01). In both groups plasma aldosterone concentration was hyperbolically and inversely correlated with urinary sodium excretion, but the two curves were progressively shifted to the left in respect to controls suggesting an enhanced renal tubular sensitivity to the hormone. The results suggest that aldosterone related renal sodium retention, with consequent blood volume expansion, occurs before ascites formation. The mineralocorticoid activity of aldosterone is amplified by an enhanced sensitivity of renal tubules which appears to increase as the disease progresses.

Adult↗

Impairment of blood pressure control in patients with liver cirrhosis during tilting: study on adrenergic and renin-angiotensin systems.

Mean arterial pressure, phenylalanine, tyrosine, norepinephrine and plasma renin activity (PRA) were determined in the plasma of 6 healthy controls and 8 patients with liver cirrhosis receiving a controlled sodium intake (40 mEq/day), after 1 h of bed rest and 10 min after being tilted up at 90 degrees. After resting, patients showed lower arterial pressure (p less than 0.025) and higher plasma levels of phenylalanine (p less than 0.005), tyrosine (p less than 0.05), norepinephrine (n.s.) and PRA (n.s.) than controls. In spite of a prolonged and marked stimulation of the adrenergic system induced by tilting, arterial pressure of cirrhotics, after an initial increase, decreased significantly. A significant PRA increase was observed in both groups but in patients it was greater and lasted longer, up to 30 min, when PRA and arterial pressure were inversely and significantly correlated. The adrenergic system of cirrhosis then appeared unable to maintain adequate levels of arterial pressure, even though hyperstimulated. The renin-angiotensin system played an important compensatory role in this contest.

Adult↗

[Catecholamine and renin-angiotensin system in blood pressure control in patients with liver cirrhosis].

The changes induced by active tilting in arterial pressure, plasma renin activity, norepinephrine and its precursors phenylalanine and tyrosine were evaluated in 8 patients with liver cirrhosis and 6 healthy controls. The results suggest the inability of the adrenergic system, though hyperstimulated, to maintain arterial pressure homeostasis in cirrhosis with a compensatory hyperactive renin-angiotensin system. Derangements in catecholamine synthesis, possibly due to altered utilisation of precursors to alternative final products (weak neurotransmitters?) can be taken into account.

Adult↗

Effects of a new loop diuretic (muzolimine) in cirrhosis with ascites: comparison with furosemide.

Muzolimine is a loop diuretic with both the dose-dependent increasing effectiveness of loop diuretics and the long-lasting effect of thiazides. This is a potential advantage in the treatment of ascites in advanced cirrhosis since these patients have a low tolerance to sudden reductions of blood volume. Equivalent single, oral doses of furosemide (40 mg) and muzolimine (30 mg) were given to 10 cirrhotic patients with ascites and reduced renal perfusion (glomerular filtration rate = 30 to 75 ml per min). The study was preceded by 4 days of equilibration (dietary sodium 40 mmoles per day), and the drugs were alternated via a single-blind, cross-over protocol after a wash-out period of 3 days. Renal function was monitored under basal conditions and after diuretic administration through 4-hr clearance periods for 24 hr. The renin-aldosterone axis was evaluated before diuretic administration and after 8 and 24 hr. Muzolimine led to a 12-hr cumulative diuresis [AUC0-12 = 2.52 +/- 0.42 (S.E.) ml per min] and natriuresis (5.14 +/- 1.05 mmoles per hr), which were comparable to those of furosemide (2.85 +/- 0.29 ml per min and 6.75 +/- 1.63 mmoles per hr). Its effect, however, was distributed over a longer period (8 hr) than furosemide (4 hr). Muzolimine activity mainly differed from furosemide because of: significantly lower 12-hr potassium excretion (AUC0-12 = 0.28 +/- 0.82 vs. 2.69 +/- 0.46 mmoles per hr; p less than 0.005); greater sodium/chloride excretion ratio (0.45 +/- 0.08 vs. 0.26 +/- 0.06; p less than 0.025), and absence of rebound phenomena.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone↗

Blastoschizomyces capitatus: an emerging cause of invasive fungal disease in leukemia patients.

Blastoschizomyces capitatus (formerly named Trichosporon capitatum or Geotrichum capitatum) is a rare cause of invasive fungal disease in immunocompromised hosts. We retrospectively studied epidemiologic, clinical, pathologic, and microbiologic features of this infection during a 68-month period at the Division of Hematology of the University La Sapienza in Rome. Twenty patients with evidence of B. capitatus were identified: 12 were infected, four were possibly infected, and four had evidence of B. capitatus colonization but were not infected by this fungus. Pulmonary infiltrates were seen in seven infected patients; four of these patients eventually developed mycetomalike cavitations. Eight infected patients presented clinical and radiologic features of focal hepatitis compatible with hepatosplenic candidiasis. Of the 12 infected patients, two did not receive any antifungal treatment and died, five did not show any response to systemic antifungal therapy, and five received prolonged amphotericin B plus 5-fluorocytosine therapy. Of the last group, three patients achieved stable remission of their acute leukemia and were cured, and two improved but had an apparent relapse of B. capitatus infection after their acute leukemia recurred.

Adolescent↗

Preliminary results of a complete study protocol on synthetic vascular graft healing and its complications.

The microscopic and anatomic features and bacteriologic culture results of different portions of single, explanted dacron synthetic vascular grafts (SVG) were studied together with patient clinical data. With this complete study protocol a better understanding of the healing process and its associated pathology can be achieved. We studied three, amply distanced graft portions from each of five patients (15 total graft portions) undergoing revision for infectious and non-infectious reasons. We divided the SVG portions studied into a Group 1, with high degrees of graft healing and into a Group 2, with both infection-dependent, early healing complications and perigraft chronic inflammatory reaction-dependent, late healing complications. These late healing complications were found dependent upon a host vs graft reaction. This study confirmed in humans the important role of an internal and external fibrotic graft incorporation in the definitive healing of a SVG. A host vs graft reaction was suggested to be an alternative to the frequently cited low virulent infection pathogenesis of late SVG healing complications. A sure definition and treatment of late SVG healing complications will only be established by means of a complete study protocol performed on a large number of explanted SVGs.

Blood Vessel Prosthesis↗