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Biomedical subjects

G Nassuato

Publications and source records attributed to G Nassuato.

At least 19 recordsLinked to original sources
PubMed1999

Gallstone disease in an elderly population: the Silea study.

BACKGROUND: Little is known on gallbladder emptying and gallstone composition in the elderly. AIMS AND SUBJECTS: Cross-sectional survey on the prevalence of gallstone disease and associated factors, gallstone characteristics and gallbladder emptying in a population aged > or = 60 years. METHODS: Gallstone number and size as well as gallbladder motor function were assessed by ultrasound. Gallstone composition and pattern were evaluated by conventional radiology and computed tomography (CT) based on Hounsfield units (HU). RESULTS: Gallstones were found in 148/1,065 subjects (13.9%), while 136 subjects (12.8%) were cholecystectomized with an overall prevalence of gallstone disease of 26.7% (sex ratio: F > M). Multiple gallstones (62.7%) and small gallstones (52%, diameter < or = 15 mm) were seen; silent gallstones accounted for 93.9% of the total. Only diabetes mellitus in women was significantly associated with cholelithiasis. Gallbladder fasting volumes were larger in gallstone carriers than in controls (P < 0.01); residual and ejection volumes were also significantly greater in gallstone carriers, whereas ejection fractions were similar in the two groups (50.3% +/- 2.4 versus 54.9% +/- 3.0; not significant). Gallstone calcifications were detected in 29/91 gallstone carriers by X-ray and in another 20 by CT (HU > 90). Moreover, 35 gallstone carriers had a score < or = 50 HU and six had attenuation values between 50 and 90 HU. Six gallstone patterns were identified: hypo-isodense, homogeneously dense, rimmed, laminated, core-hyperdense, gas-containing. CONCLUSIONS: In the elderly, the prevalence of gallstone disease is very high, especially in women, but gallstone size, number and pattern and gallbladder emptying do not differ from those reported in the middle-aged gallstone population. Advanced age is associated with a high rate of calcified, probably pigment stones.

Age Factors↗
PubMed1998

Hepatitis C virus infection and related chronic liver disease in a resident elderly population: the Silea Study.

The prevalence of hepatitis C virus (HCV) infection increases with advancing age, but the disease has been poorly studied in the elderly. A population-based study was therefore carried out to investigate the prevalence of HCV infection and the severity of HCV-related chronic liver disease in the elderly. One thousand and sixty-three people (> or = 60 years of age) were screened for antibodies to HCV (anti-HCV) and for possible abnormalities of common liver function tests. Positive subjects and sex and age-matched anti-HCV-negative controls were recalled 12 months later for measurements of liver enzymes, confirmatory testing of anti-HCV, HCV RNA analysis and HCV genotyping. All subjects answered a specific questionnaire concerning medical history and possible risk factors. Forty-four subjects were positive for anit-HCV, the prevalence being 4.1%. Thirty-five positive subjects and 35 controls were investigated further. Risk factors for acquiring HCV were found to be: blood transfusion, surgical intervention and the use of non-disposable syringes. Abnormal alanine aminotransferase levels were found in 13 patients (37.1%). HCV RNA genotyping showed type 1b in three (15.8%), type 2a in 13 (68.4%) and not classified in three (15.8%) patients. There was no relationship between abnormalities of serum aminotransferase, the rate of HCV RNA positivity and HCV genotypes. Ultrasound abnormalities were present in 13 (37.1%) patients. In this elderly population the relatively high prevalence of HCV infection was thought to be caused by previous parenteral exposure. The low incidence of liver disease could be related to the prevalence of HCV genotype 2a in the majority of these patients, and hints at the possibility of an HCV carrier state in elderly individuals.

Aged↗
PubMed1993

Clinical, ultrasonographic, and roentgenographic study in 134 asymptomatic gallstone carriers. Is oral ursodeoxycholic acid treatment worthwhile?

We investigated retrospectively the ultrasonographic and roentgenographic characteristics of the gallstones and the gallbladder in 134 symptom-free carriers and evaluated prospectively the outcome and side effects of 6 to 24 months' ursodeoxycholic acid (UDCA) therapy in 36 individuals with silent stones. Two-thirds of the 134 subjects had multiple stones, and 71-75% had stones less than 15 mm in diameter. Gallstone calcification was detected in 13%. A non-functioning gallbladder was observed in 19%, whereas gallbladder contraction was normal in 64 of 76 gallstone carriers. With regard to oral bile acid treatment, complete and partial dissolutions were achieved in 7 and 9 of 33 subjects, respectively (48.5%). Development of a non-functioning gallbladder occurred in 9%, and acquired gallstone calcification was seen in another 15%. We conclude that: i) the characteristics of the gallstones and the gallbladder are similar to those observed in symptomatic patients, and ii) UDCA therapy may be given in selected symptom-free carriers for no more than 6-12 months. Thereafter, it does not appear to be cost-effective.

Administration, Oral↗
PubMed1991

Effect of Silibinin on biliary lipid composition. Experimental and clinical study.

The effect of Silymarin, a natural flavonoid, on biliary lipid composition, was studied in rats and humans. Bile flow, biliary cholesterol, phospholipid and total bile salt concentrations were measured in 23 control rats and in 27 rats treated with Silibinin, the active component of Silymarin, at the dose of 100 mg/kg body weight i.p. (n = 21) or 50 mg/kg body weight i.p. (n = 6) for 7 days. Biliary cholesterol and phospholipid concentrations were significantly reduced after the higher Silibinin dose (60.9 and 72.9% of the control values), whereas bile flow and biliary total bile salt concentration were unchanged. After the lower Silibinin dose all parameters remained unchanged. Total liver cholesterol content was not affected by Silibinin. On the other hand, in vitro determination of rat liver microsomal 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase activity showed a significant dose-dependent inhibition by Silibinin (0.5-8 mg/kg). Biliary lipid composition was also assayed in four gallstone and in 15 cholecystectomized patients before and after Silymarin (420 mg per day for 30 days) or placebo administration. In both groups, biliary cholesterol concentrations were reduced after Silymarin treatment and the bile saturation index significantly decreased accordingly. These data suggest that Silibinin-induced reduction of biliary cholesterol concentration both in humans and in rats might be, at least in part, due to a decreased synthesis of liver cholesterol.

Adult↗
PubMed1990

[The prevalence of diffuse and focal lesions of the hepatic parenchyma in a nonselected, resident population. A prospective echographic study].

A group of 2978 randomly chosen residents from a rural area of Veneto (Italian region), aged 18-69 years, was assumed as a study population. They underwent US examination of the liver, routine liver function tests, and--when necessary--other imaging techniques and liver biopsy. Liver US exam detected diffuse lesions in 26% of cases (mostly bright liver pattern), and focal lesions in 3%; US findings were normal in 66% of patients and questionable or inconclusive in 5%. As far as focal lesions were concerned, the final diagnosis was angioma (24 cases), cyst (31), neoplasm (5). When bright liver pattern was observed, liver function tests were altered in 78% of the patients; when US findings were normal, liver function tests were normal in 59% of cases. In conclusion our data: 1) show that focal and diffuse liver abnormalities are relatively frequent in unselected and asymptomatic people, 2) confirm US diagnostic utility, and 3) suggest that US be employed as a screening exam in study populations.

Adolescent↗
PubMed1989

[Renal parenchymal neoplasm as a chance finding during hepatobiliary echography].

Renal cell carcinomas are often diagnosed as incidental findings during abdominal US or CT carried out for extra-urological reasons. In order to ascertain the incidence of renal carcinoma two groups of patients were considered: a) 2400 outpatients who had undergone hepato-biliary US for routine screening; b) 1330 inpatients who had undergone US, for non-urological purposes, which had been systematically extended to the kidneys. Two cases of renal cell carcinoma (PT1) were found in group A. Four cases were found in group B--2 of them were stage PT1, and 2 were PT3. These results show how a certain number of unsuspected and early-stage renal cell carcinomas can be diagnosed by US, even when the examination is not intended as a renal study. On the basis of the above observations, we suggest that US be performed in all upper abdomen examinations. At any rate, right kidney US seems to us mandatory when hepatobiliary US is performed.

Adolescent↗
PubMed1988

[Echography with portable equipment. Its possibilities and limits in the hepatobiliary area].

Ultrasound examination of the liver by simple low-cost equipment (LCUS) is currently performed. In order to evaluate the accuracy of this imaging technique in the detection of liver diseases, 150 outpatients were examined with a LCUS unit. The same patients were then re-examined with more sophisticated equipment (SEUS) in a department of radiology. The images thus obtained were compared to the previous ones: LCUS appears to be a valuable screening method, even though several US features--i.e. hyperechogenicity of the liver, focal hypoechoic lesions, and microlithiasis--are better demonstrated by more sophisticated units.

Adolescent↗
PubMed1986

The effect of drugs on bile flow and composition. An overview.

Many drugs are eliminated via the hepatobiliary route, after biotransformation in the liver. Some of them may affect bile flow and/or the hepatic secretion of biliary lipids such as bile acids, cholesterol and phospholipids. Bile acids are the most potent agents which increase bile flow, especially unconjugated bile acids. Other drugs which increase bile flow include phenobarbitone (phenobarbital), theophylline, glucagon and insulin. In contrast, ethacrynic acid, amiloride, ouabain, oestrogens and chlorpromazine are among those agents which decrease bile flow. Biliary bile acid secretion is altered by a variety of drugs, including cheno- and ursodeoxycholic acids (CDCA and UCDA), the bile acid sequestrants cholestyramine and colestipol, and ethinyloestradiol. The composition of bile can also be altered by drug therapy. Thus, clofibrate increases biliary cholesterol secretion, and reduces bile acid concentrations, without altering biliary phospholipid concentrations. However, other clofibrate derivatives may produce changes of a different pattern, suggesting that the risk of developing gallstones may differ for each derivative. Nicotinic acid and d-thyroxine also increase biliary cholesterol saturation, while CDCA and UDCA reduce biliary cholesterol concentration. The potential consequences of drug-induced changes in bile flow and composition extend to the liver, the gallbladder and the intestine. If adverse effects are to be avoided, further study in this often overlooked area is required.

Animals↗
PubMed1985

Pharmacokinetics of Josamycin in patients with liver cirrhosis and Gilbert's syndrome after repeated doses.

The pharmacokinetics of Josamycin was studied in 31 subjects (10 normals, 9 Gilbert's syndrome and 12 compensated liver cirrhosis) after the administration of Josamycin (1 g orally) and in 13 subjects (4 normals, 4 Gilbert's syndrome and 5 compensated liver cirrhosis) after 3-day Josamycin treatment (1 g orally every 12 hours). Josamycin pharmacokinetics was impaired in liver cirrhosis and, to a lesser extent, in Gilbert's syndrome. Moreover, in the three groups of individuals studied the drug accumulated after multiple dosing. These results suggest that a dosage adjustment of Josamycin is recommended when dealing with these patients.

Adult↗
PubMed1984

Oral and intravenous pharmacokinetics of ranitidine in patients with liver cirrhosis.

The kinetics of p. o. (150 mg) and i.v. (50 mg) ranitidine was studied in nine healthy controls and in nine patients with compensated liver cirrhosis. Plasma concentrations and urinary recovery of unchanged drug were determined by high performance liquid chromatography. The pharmacokinetic data observed in the cirrhotic patients did not differ from those of controls after p.o. or i.v. administration. Moreover, oral bioavailability was similar in controls and cirrhotics. In conclusion, the pharmacokinetics of ranitidine is not altered in patients with compensated liver cirrhosis.

Administration, Oral↗
PubMed1984

The pharmacokinetics of H2 receptor blocking agents in compensated liver cirrhosis.

The bioavailability of oral and intravenous cimetidine and ranitidine was studied in patients with compensated liver cirrhosis. Single doses of 200 and 400 mg cimetidine were used for both administration routes, while ranitidine was administered in doses of 150 mg orally or 50 mg i.v. Plasma concentrations and urinary recovery were determined by the HPLC method. The pharmacokinetics of both of these drugs in the cirrhotic patients did not differ from those found in normal subjects. The two doses of cimetidine given i.v. gave rise to the same plasma concentrations, while after oral administration, 400 mg produced higher plasma concentrations than 200 mg. As to the pharmacokinetic parameters, neither cimetidine nor ranitidine administered i.v. offered any further advantages compared to the oral route. The urinary recovery of both cimetidine and ranitidine was higher after intravenous than after oral administration. It is concluded therefore that the pharmacokinetics of cimetidine and ranitidine is not altered in compensated liver cirrhosis.

Administration, Oral↗
PubMed1983

Effect of Silybin on biliary lipid composition in rats.

The authors studied the influence of Silybin in rats, administered i.p. for 7 days (daily dose of 100 mg/kg/b.w.) on the biliary lipid composition and on the maximal excretory rate of bile salts. Following this treatment, biliary cholesterol excretion was reduced, while the other lipids and bile flow were not significantly modified. After sodium cholate infusion (1.6 mumol/min/100 g b.w. i.v. for 80 minutes), the Tm of bile salts and bile flow remained unchanged in Silybin pretreated rats. The mechanism by which Silybin treatment reduces cholesterol excretion, is discussed.

Animals↗
PubMed1982

Oral and intravenous pharmacokinetics of cimetidine in liver cirrhosis.

The bioavailability of p.o. and i.v. cimetidine was studied in 12 patients with compensated liver cirrhosis in a crossover study. Single doses of 200 and 400 mg cimetidine were used for both administration routes. Plasma concentration and urinary recovery were determined by the HPLC method. The pharmacokinetic data observed in these patients do not differ from those of normal subjects and patients. A positive correlation between AUC and cimetidine oral dose was found. Oral bioavailability of cimetidine was about 94% compared to that of the i.v. route. The p.o. dose of 400 mg produced AUC values similar to the i.v. dose of 400 mg. After 400 mg cimetidine p.o. the mean peak plasma level was higher and the time for which plasma levels remained above 0.5 mg/l was longer. There were no significant differences between plasma cimetidine levels after the intravenous administration of 200 and 400 mg. The urinary recovery of cimetidine was significantly higher after intravenous administration independently of the given dose. The pharmacokinetics of cimetidine does not appear to be altered in liver cirrhosis.

Administration, Oral↗
PubMed1981

Biliary excretion of simultaneously administered bilirubin and chenodeoxycholic acid in rats.

Crystalline bilirubin and chenodeoxycholic acid were administered intravenously and intraduodenally respectively in 19 anesthetized Sprague-Dawley rats in order to verify whether there exists an interference between their biliary excretion. When these two compounds were administered together, the biliary excretion of bilirubin and bile salts was significantly reduced the conjugation of bilirubin was not impaired while bile flow remained constant during the whole exerpimental period. These data seem to indicate a mutual interference between chenodeoxycholic and bilirubin metabolisms. It could be admitted that the excretory step is involved in determining the observed modifications.

Animals↗