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L Pagliaro

Publications and source records attributed to L Pagliaro.

At least 109 records · Page 6Linked to original sources
PubMed1990

Role of S-adenosyl-L-methionine in the treatment of intrahepatic cholestasis.

Recent studies have established the clinical efficacy of S-adenosyl-L-methionine (SAMe) in the treatment of cholestasis associated with hepatic diseases, pregnancy and the administration of estrogen-containing oral contraceptives. In 4 clinical trials involving a total of 639 patients with cholestasis due to acute or chronic liver disease, SAMe in an intravenous dose of 800 mg/day or an oral regimen of 1.6 g/day for 2 weeks was superior to placebo in relieving the symptom of pruritus and in restoring serum total bilirubin and serum alkaline phosphatase towards normal. The drug is also effective in intrahepatic cholestasis of pregnancy (ICP), with intravenous administration of 800 mg/day for 2 weeks producing a substantial reduction in pruritus and an improvement in abnormal liver function indices. Moreover, SAMe treatment decreases the incidence of premature labour. SAMe appears to be the first safe and effective approach to the treatment of this syndrome, and also protects against the adverse hepatic effects of small doses of estrogen in patients with a history of ICP by normalising liver biochemistry and the oversaturated biliary lipid composition of the gallbladder bile. In animal models, SAMe reverses the pathological liver changes induced by xenobiotics such as taurolithocholate and alpha-naphthyl-isothiocyanate (ANIT) and the antipsychotic chlorpromazine. Several cooperative mechanisms appear to underlie the anticholestatic action of SAMe, the most important being the restoration of normal hepatocyte membrane fluidity and Na+, K+ ATPase activity, through a reversal of the reduction in phospholipid methylation produced by hepatotoxic agents. In addition, SAMe may act by promoting trans-sulphuration pathway reactions and consequently improving the detoxifying capacity of this metabolic system.

1-Naphthylisothiocyanate↗
PubMed1989

Hepatitis B vaccination of relatives of hepatitis B virus DNA positive carriers: an experience with plasma-derived vaccine.

We assessed in a western population the efficacy of a plasma-derived hepatitis B vaccine in relatives of highly infectious hepatitis B virus (HBV) carriers. A consecutive group of 103 HbsAg, anti-HBs and anti-HBc negative household relatives of 45 HBV-DNA positive chronic carriers received a 5 micrograms dose of plasma-derived vaccine at 0, 1, 2 and 12 months. Protective levels of immunity developed in 101 subjects (97.8%) 3 months after boosting. Low responders to the vaccine were mostly found among parents and spouses of carriers, whilst offspring and siblings were usually high responders. The main discriminant in predicting a good response was age below 12 years. Hyporesponsiveness did not occur in family clusters. No major HBV events occurred among immunized relatives patients. Hepatitis B vaccine is safe and effective in immunizing relatives of HBV carriers while no genetic conditioning of the immune response is evident among them.

Adult↗
PubMed1989

Concanavalin A inhibits mating type recognition in Tetrahymena.

The lectin concanavalin A (Con A) inhibits adhesion of cells of complementary mating types into pairs during conjugation in the ciliate Tetrahymena thermophila. Distinct changes in protein synthesis occur in conjugating Tetrahymena, starting before cells have paired, as a result of a preliminary interaction, costimulation, involving nonadhesive, contact-mediated, specific cell-cell recognition. We report here that ConA inhibits costimulation-induced protein synthesis changes. We interpret this result as evidence that Con A inhibits cellular recognition, independent of cell-cell adhesion, in Tetrahymena.

Animals↗
PubMed1989

Enolase exists in the fluid phase of cytoplasm in 3T3 cells.

We have investigated the intracellular distribution and mobility of the glycolytic enzyme enolase, using functional fluorescent analogs labeled with the succinimidyl esters of carboxyfluorescein (F1-enolase) and carboxytetramethylrhodamine (Rh-enolase) In contrast to aldolase, neither native enolase nor labeled enolase gelled filamentous actin (F-actin), as measured by falling-ball viscometry, indicating a lack of interaction between enolase and F-actin. Fluorescence redistribution after photo-bleaching (FRAP) measurements of the diffusion coefficient (D) of F1-enolase in aqueous solutions gave a value of D37,aq = 6.08 x 10(-7) cm2s-1, and no immobile fraction, consistent with a native molecular weight of 90,000. These values were not significantly different with Rh-enolase, or in the presence of F-actin, 2-phosphoglycerate or F-actin-aldolase gels, demonstrating that neither F1-enolase nor Rh-enolase binds to F-actin or aldolase in vitro. FRAP measurements of F1- and Rh-enolase microinjected into living Swiss 3T3 cells revealed spatial differences in the diffusion coefficient, but not the mobile fraction. In the perinuclear cytoplasm, we measured an apparent diffusion coefficient of 1.1 x 10(-7) cm2s-1, compared to 7.1 x 10(-8) cm2s-1 in the peripheral cytoplasm, with approximately 100% mobility of F1- or Rh-enolase in both regions. Imaging of cells co-injected with Rh-enolase and size-fractionated FITC-dextran (FD-90) revealed that Rh-enolase entered the nucleus, while FD-90 was excluded. Ratio imaging showed a relatively high nuclear ratio of Rh-enolase/FD-90, and a uniform cytoplasmic ratio, with no indication of increased concentration of enolase around stress fibers. These data demonstrate that Rh- and F1-enolase do not bind to F-actin in vitro, and are 100% mobile in vivo. Together with our recent finding that a significant fraction of aldolase binds to F-actin in vitro and is immobile in vivo, these data suggest a correlation between actin-binding activity and cytoplasmic mobility of glycolytic enzymes.

Animals↗
PubMed1989

A randomised controlled trial of propranolol for the prevention of initial bleeding in cirrhotic patients with portal hypertension. Preliminary results. The Italian Multicenter Project for Propranolol in the Prevention of Bleeding.

The preliminary analysis of a multicentre, randomised, single-blind trial of propranolol for prophylaxis of first bleeding in cirrhosis is reported. 174 consecutively-chosen patients with large oesophageal varices were randomly assigned to either propranolol, in doses which reduced the resting heart rate by 25% (85 patients), or to vitamin K (89 patients). 25 patients had to be withdrawn from treatment with propranolol because of poor tolerance. The 30-month cumulative proportion of patients free of bleeding was 74% in the propranolol group and 63% in the vitamin K group; corresponding survival figures were 59% and 74%, respectively. These differences were not statistically significant. A retrospective analysis, according to the presence of ascites at randomisation showed that a significantly higher proportion of patients without ascites in the propranolol group were free of bleeding compared with those in the control group (87% vs 64%; p = 0.023). No significant differences were found in patients with ascites at randomisation. Length of survival was not significantly affected by treatment in any subgroup, although it was shorter in ascitic patients given propranolol than in controls (33% vs 63%; p = 0.07). If confirmed on a longer follow-up, these results suggest that propranolol could prevent primary variceal haemorrhage in patients with well-compensated cirrhosis.

Aged↗
PubMed1989

Hospital incidence of Crohn's disease in the province of Palermo. A preliminary report.

The hospital incidence of Crohn's disease in the province of Palermo was studied from January 1987 to June 1988. A total of 51 patients (34 in 1987 and 17 in the first half of 1988) were diagnosed. The incidence rate calculated for the 1st year was 2.7/100,000. A similar figure was observed in the first 6 months of 1988, which ought to rule out an overestimation in the 1st year. These preliminary data suggest that the incidence of Crohn's disease in southern Italy is similar to that reported in northern Europe.

Crohn Disease↗
PubMed1988

Ultrasonography and alpha-fetoprotein in diagnosis of hepatocellular carcinoma in cirrhosis.

The accuracy of ultrasound (US) and alpha-fetoprotein (AFP) in the diagnosis of hepatocellular carcinoma (HCC) in 363 patients with cirrhosis (C) and a clinical suspicion of HCC was assessed. The ultrasonographic patterns of HCC and their relationship with AFP values were analyzed. Echographic patterns were distributed as follows: 47 patients had sonodense lesions; 30 patients had hypoechoic lesions; 47 had mixed-pattern lesions, and in four patients focal dilated intrahepatic bile ducts were demonstrated. The sensitivity of US was 90%; specificity was 93.3%. Serum AFP level greater than or equal to 500 ng/ml (RIA) was the first clue to the diagnosis in 71 patients (48.6%); specificity was 100%. In 28 patients AFP levels became significantly elevated during follow-up after US detection of HCC. No relationship between echo pattern and serum AFP levels was demonstrated. An algorithm for diagnosis of HCC is proposed.

Algorithms↗
PubMed1988

Aldolase exists in both the fluid and solid phases of cytoplasm.

We have prepared a functional fluorescent analogue of the glycolytic enzyme aldolase (rhodamine [Rh]-aldolase), using the succinimidyl ester of carboxytetramethyl-rhodamine. Fluorescence redistribution after photobleaching measurements of the diffusion coefficient of Rh-aldolase in aqueous solutions gave a value of 4.7 x 10(-7) cm2/S, and no immobile fraction. In the presence of filamentous actin, there was a 4.5-fold reduction in diffusion coefficient, as well as a 36% immobile fraction, demonstrating binding of Rh-aldolase to actin. However, in the presence of a 100-fold molar excess of its substrate, fructose 1,6-diphosphate, both the mobile fraction and diffusion coefficient of Rh-aldolase returned to control levels, indicating competition between substrate binding and actin cross-linking. When Rh-aldolase was microinjected into Swiss 3T3 cells, a relatively uniform intracellular distribution of fluorescence was observed. However, there were significant spatial differences in the in vivo diffusion coefficient and mobile fraction of Rh-aldolase measured with fluorescence redistribution after photobleaching. In the perinuclear region, we measured an apparent cytoplasmic diffusion coefficient of 1.1 x 10(-7) cm2/s with a 23% immobile fraction; while measurements in the cell periphery gave a value of 5.7 x 10(-8) cm2/s, with no immobile fraction. Ratio imaging of Rh-aldolase and FITC-dextran indicated that FITC-dextran was relatively excluded excluded from stress fiber domains. We interpret these data as evidence for the partitioning of aldolase between a soluble fraction in the fluid phase and a fraction associated with the solid phase of cytoplasm. The partitioning of aldolase and other glycolytic enzymes between the fluid and solid phases of cytoplasm could play a fundamental role in the control of glycolysis, the organization of cytoplasm, and cell motility. The concepts and experimental approaches described in this study can be applied to other cellular biochemical processes.

Animals↗
PubMed1988

Early detection of hepatocellular carcinoma associated with cirrhosis by ultrasound and alfafetoprotein: a prospective study.

A prospective surveillance of hepatocellular carcinoma (HCC) associated with cirrhosis, using alfafetoprotein (AFP) and real-time ultrasonography (US) was carried out in 157 patients with histologically proven cirrhosis. During a two-year follow-up, 15 asymptomatic HCCs were identified. HCCs detected by these methods were at a relatively early stage, as most tumors were small (13 out of 15 less than 5 cm). US was more sensitive than AFP in the diagnosis of HCC when values greater than 400 ng/ml were considered. Patients with initial AFP values greater than 20 ng/ml developed HCC within two years more frequently than patients with values less than 20 ng/ml. A combined approach using US and AFP is suggested in our geographical area.

Carcinoma, Hepatocellular↗
PubMed1987

Procollagen type I production by hepatocytes: a marker of progressive liver disease?

The presence of collagen-producing cells and its relation to disease activity were determined in cryostat liver tissue sections from subjects with active cirrhosis (n = 15), inactive cirrhosis (n = 5), chronic persistent hepatitis (n = 8), or normal histology (n = 3) by means of an immunofluorescence technique using a monoclonal antibody to the carboxy-terminal domain of procollagen type I (anti-Pc). In all patients with active cirrhosis hepatocytes showed a strong intracellular staining with anti-Pc; in 4 of them bileducts also showed a membrane-like reaction. By contrast, tissue sections from chronic inactive liver disease and normal liver were essentially negative. These findings suggest that in chronic liver disease hepatocytes and sometimes biliary epithelium produce collagen and that production is related to disease activity. The detection of active production of procollagen type I by hepatocytes could become a useful marker of progressive liver disease.

Adult↗
PubMed1987

Concanavalin A binding induces association of possible mating-type receptors with the cytoskeleton in Tetrahymena.

The lectin concanavalin A (conA; 25 micrograms/ml) inhibits conjugation in the ciliate Tetrahymena, and binds to receptors localized at the junction between conjugating cells. We report here that succinyl-conA (30 micrograms/ml) has similar activity, but that two other mannosespecific lectins, lentil and pea lectins, have inhibitory activities more than tenfold lower in this system, indicating that factors other than mannose specificity are essential for biological activity. By using fluorescein-isothiocyanate (FITC)-conA, we have found that extraction of cells with the detergent Triton X-100 removes conA receptors from the extraction-resistant cytoskeleton, but that the binding of conA to its receptor before extraction associates the ligand-receptor complex with the cytoskeleton. Under the hypothesis that the conA receptor may be a mating type receptor, we have used this ligand-induced differential cytoskeletal association, in conjunction with electrophoresis and Western blotting, to identify a glycoprotein with an apparent molecular weight (MW) of 23,000 D which may be a mating type receptor. Our data are consistent with a model in which a direct interaction between the conA receptor and the cytoskeleton, rather than receptor cross-linking, is the biologically significant activity of ligand binding.

Animals↗
PubMed1987

Sludge and stones in gallbladder after pregnancy. Prevalence and risk factors.

The prevalence of sludge and stones in the gallbladder of 298 women in the immediate post-partum period was ultrasonographically assessed. We have investigated some risk factors for the development of sludge or stones in these patients and followed up most of these patients by ultrasonography to detect the presence of sludge and/or stones in the year following their discovery. We found sludge in 80 (26.2%) and gallstones in 16 (5.2%) of these patients. Age, obesity and months of oral contraceptive use were risk factors only for the presence of gallstones. After 1 year of follow-up only 2 out of 45 patients with sludge but 13 out of 15 patients with gallstones still had abnormal ultrasonographic findings.

Adult↗