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Biomedical subjects

M Chiaramonte

Publications and source records attributed to M Chiaramonte.

At least 37 records · Page 2Linked to original sources
PubMed1991

Age- and sex-related study of HBV-DNA in HBsAg asymptomatic children from an endemic area (Cameroon).

A sero-epidemiological survey was carried out in Cameroon in January 1989 on a sample of 702 children of primary school age. A high HBV endemicity level was observed: 60.3% of the sera were positive to any HBV marker, 23.2% (163 sera) were HBsAg-positive. HBV-DNA positivity was observed in 38/163 (23.3%), thus showing a high level of infectivity among these carriers. Seventy-seven HBsAg-positive sera were tested for HBeAg/anti-HBe: 20 (26%) were HBeAg-positive 31 (40%) anti-HBe-positive, and 26 (34%) were negative for both. All sera were anti-HD-negative. Twenty-five per cent of HBeAg-positive sera were HBV-DNA-negative. This finding could be explained by a delayed HBeAg/anti-HBe seroconversion phase with fluctuant HBV-DNA. Only one case of HBV-DNA-positive anti-HBe-positive serum was observed. This study showed that HBV-DNA prevalence was significantly higher in boys (31.8%) than in girls (14.1%) (p less than 0.02). This difference was not observed for any HBV marker. We therefore conclude that in boys a prolonged HBV replicative phase might explain the observed high chronicity rate.

Age Factors↗
PubMed1991

A high degree of exposure to hepatitis A virus infection in urban children in Cameroon.

In January 1989, the prevalence of antibodies to hepatitis A virus (anti-HAV) was determined by ELISA in 702 apparently healthy children 5-14 years old in Kumba City, Cameroon. Children were recruited from those attending six different primary schools, representative of the socio-demographic characteristics of the inhabitants, using a systematic random sampling. The overall IgG anti-HAV prevalence was 96.9%, reaching 100% by the age of 11 years. In primary school beginners the prevalence was very high, 94.0%, contrary to what has been observed in developed countries. The anti-HAV prevalence was not associated with family size, but was related to parent's occupation, children from the lower class having a 5.9 fold risk (C.I. = 1.9-18.3) of past exposure to HAV. These results suggest a persistently high prevalence of anti-HAV in children despite improving hygienic conditions. The spread of HAV in this population may be the result of domestic water and/or food contamination.

Adolescent↗
PubMed1991

Hepatitis-C virus infection in Italy: a multicentric sero-epidemiological study (a report from the HCV study group of the Italian Association for the Study of the Liver).

To assess possible geographical differences in the spread of hepatitis-C virus (HCV), the prevalence of antibodies against HCV (anti-C-100-3) was investigated in various adult population groups in 29 centres in Italy. Anti-HCV was positive in 375 out of 28,433 voluntary blood donors (1.3%): prevalence was higher in southern Italy (1.51%) than in the northern regions (1.28%), but the difference was not statistically significant. Anti-HCV prevalence was similar in the north and south in post-transfusion chronic hepatitis (91%), haemophiliacs (73%), intravenous drug users (70%), and haemodialysis patients (28%), where parenteral contacts are obvious, and in HBsAg carriers (14%), a group with evidence of previous parenteral contamination. In contrast, anti-HCV prevalences were found to be significantly higher in the south than in the north and central Italy among patients with hepatocellular carcinoma (HCC) (73 vs 59%), cryptogenic liver disease (67 vs 58%), autoimmune chronic hepatitis (72 vs 44%) and alcoholic liver disease (51 vs 34%). These results indicate a very high circulation of HCV in Italy, with maximum incidence in the south and in the islands. They suggest that its spread in the community can occur through inapparent parenteral routes as observed for hepatitis-B (HBV) and hepatitis-delta viruses (HDV) and possibly facilitated by poorer social-demographic and life-style factors.

Adult↗
PubMed1991

Sex hormone changes in post-menopausal women with primary biliary cirrhosis (PBC) and with cryptogenic chronic liver disease.

Sex hormones and sex hormone binding globulin (SHBG) have been studied in 32 female post-menopausal patients (16 with Primary Biliary Cirrhosis (PBC) and 16 with cryptogenic chronic liver disease (CLD). Dehydroepiandrosterone-sulfate (DHEA-S) serum levels were significantly higher in PBC compared to CLD subjects (p less than 0.005). In PBC DHEA-S concentration was higher in precirrhotic than in cirrhotic patients (p less than 0.02). SHBG was raised in both PBC and CLD patients but higher in CLD compared to PBC subjects (p less than 0.002). PBC reveals a sex hormone pattern similar to post-menopausal subjects with breast cancer. These results suggest that sex hormone alteration is present in females with different types of liver disease, but the metabolic pattern is not due to liver disease per se.

Aged↗
PubMed1991

Primary biliary cirrhosis in the elderly.

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease with onset about menopause. To investigate its clinical features and the natural history in relation to age, we examined 86 consecutive patients with PBC (81 F, 5 M); 70 were less than 65 years (mean age 48 years) and 16 greater than 65 years (mean age 69 years). All patients were followed-up for 6 months-16 years (mean 4 years). Histological stage at presentation was comparable in the two groups, but among aged PBC subjects there was a significantly higher prevalence of asymptomatic patients (56% vs 24%, p less than 0.001). No significant differences were observed in the biochemical indices and immunological abnormalities. Survival curves showed no significant differences in PBC according to the age. Mortality was observed only in the group less than 65 years (15/70, 21.4%). In conclusion, the large proportion of asymptomatic subjects in the elderly PBC patients accounts for the similar survival in the two groups of patients.

Adult↗
PubMed1991

Prevalence of Toxoplasma gondii antibodies among children and teenagers in Italy.

Between 1987 and 1989, the prevalence of antibodies to Toxoplasma gondii was determined by ELISA in serum samples from 1,494 apparently healthy subjects, 3-18 years old. Subjects were selected by a systematic cluster sampling from five geographical areas in Italy. The overall prevalence of antibodies was 17.9%, increasing from 4.7% in 4-6 year olds to 28.4% in 17-18 year olds (P less than 0.01). A slight predominance was observed among males (18.2% vs. 17.5% in females), as well as among subjects residing in Southern Italy and the Islands (21.9% vs. 19.2% in subjects residing in the North), but neither difference was statistically significant. Toxoplasma infection was associated with sociodemographic factors. Subjects belonging to a household with six or more persons had a 1.8-fold risk (C.I. 95% = 1.3-2.6) and subjects whose fathers had less than six years of schooling had a 2.7-fold rosk (C.I. 95% = 1.8-3.9) of previous exposure to toxoplasma infection. Considering the large proportion (70%) of young women entering childbearing age without toxoplasma antibodies, it appears that the risk of congenital toxoplasmosis will not be negligible in Italy in forthcoming years.

Adolescent↗
PubMed1990

High genomic variability in the pre-C region of hepatitis B virus in anti-HBe, HBV DNA-positive chronic hepatitis.

Some chronic HBV carriers have circulating HBV DNA despite the presence of anti-HBeAg antibodies. This observation has recently been related to the presence, in the HBV pre-C region, of a translational stop codon that prevents HBeAg synthesis. In the present study, we analyzed, at the nucleotide level, the pre-C/C region of HBV isolated from the sera of 11 anti-HBe, HBV DNA-positive chronic carriers. Nucleotide sequence analysis of 25 independent clones revealed that the pre-C sequence is highly variable, even among clones derived from the same serum sample. Moreover, our data show that HBeAg synthesis can also be prevented by as yet undescribed T-C substitution at position 1815 that eliminates the start codon of the pre-C transcript. These results suggest that the HBV genome contains segments of high variability that have probably been selected during evolution to favor the segregation of functionally advantaged mutants capable of avoiding host immunity.

Base Sequence↗
PubMed1990

Unresectable hepatocellular carcinoma: a prospective controlled trial with tamoxifen.

The liver is an estrogen responsive organ. Clinically, estrogens may play a role in the induction of liver tumors and, experimentally, estrogens are involved in the control of hepatocyte proliferation. The results of a prospective controlled clinical trial using an anti-estrogen, tamoxifen, in patients with unresectable hepatocellular carcinoma (HCC) are presented below. Thirty-eight consecutive cirrhotics with HCC were allocated to either 30 mg/day tamoxifen or no treatment. The two groups of patients were matched for mean age, male/female ratio, Child-Pugh risk group, approximate tumor volume (US and/or CT scan) and etiology of the underlying cirrhosis. The drug appeared to have no side effects. Survival was significantly prolonged in tamoxifen-treated patients with 22% (vs. 5%) survival at 12 months. No differences were observed between males and females or alcoholic and non-alcoholic cirrhosis. In 53% of tamoxifen-treated patients the levels of alpha-fetoprotein dropped and, in this subgroup, survival was further prolonged. Tumor volume, lactate dehydrogenase (LDH) and alkaline phosphatase slowly increased, suggesting a slower, but continuous, progression of the disease. In conclusion, anti-estrogen treatment appears effective in the palliation of unresectable or otherwise untreatable HCC. A reduction in alpha-fetoprotein levels appears to be a favorable prognostic index.

Aged↗
PubMed1990

Pediatric HBsAg chronic liver disease and adult asymptomatic carrier status: two stages of the same entity.

Unlike adults (greater than 60% of cases), it is rare to find the chronic hepatitis B virus (HBV) carrier status with normal transaminases among children. The aim of this study was to investigate whether this status would depend on the duration of HBV infection, that is, whether chronic hepatitis in childhood would lead to the asymptomatic carrier status in later life. We reexamined all of our patients with chronic HBV infection of greater than 10 years' duration and with histologically documented chronic hepatitis during childhood. This was a group of 36 adolescents and young adults. All subjects were screened for tumor using alpha-fetoprotein assay and hepatic ultrasound. Eight patients with cirrhosis underwent esophageal fiberoptic endoscopy. All patients were in good general condition, with no clinical signs of liver failure. Only two patients had abnormal transaminase levels, both of whom had evidence of delta infection. All but one patient became anti-HBe positive. Five cases had HBsAg clearance. (Seventy-one percent of patients were HBeAg positive and 14% anti-HBe positive at the onset of the disease.) Hepatic ultrasound revealed no tumors in any of the subjects, and fiberoptic endoscopy demonstrated no esophageal varices. This study suggests that (a) chronic hepatitis and asymptomatic carrier status may be subsequent stages of the B virus infection; and (b) chronic hepatitis in childhood is generally benign and may evolve into an asymptomatic carrier status. The main problem with the chronic carrier status is probably the increased risk of hepatocellular carcinoma.

Adolescent↗
PubMed1990

Isolation of a Trypanosoma cruzi antigen by affinity chromatography with a monoclonal antibody. Preliminary evaluation of its possible applications in serological tests.

By affinity chromatography with a monoclonal antibody (163B6), obtained in our laboratory, we have isolated a T. cruzi antigen which could be useful for differential diagnosis of Chagas' disease from leishmaniasis. This antigen, a 52-kD protein, reacted with all sera from Chagas' disease patients tested but not with sera from patients with leishmania, in ELISA. The 52-kD antigen is widely distributed in the Trypanosoma genus since the 163B6 monoclonal antibody reacts with T. rangeli and 8 strains and a clone of T. cruzi epimastigotes.

Animals↗
PubMed1989

Hyperthyroidism associated with primary cirrhosis. Two case reports.

Only a single case of Graves' disease has been reported so far in Primary Biliary Cirrhosis (PBC), whereas hypothyroidism is a rather common association. We report two cases of hyperthyroidism associated with PBC. A common pathogenic mechanism involving HLA II class antigens is suggested.

Female↗
PubMed1988

Lipoprotein pattern and plasma lipoprotein lipase activities in patients with primary biliary cirrhosis. Relationship with increase of HDL2 fraction in Lp-X-positive and Lp-X-negative subjects.

Plasma lipids, apoprotein A-I and B in serum and in lipoprotein fractions (VLDL + LDL, HDL2, and HDL3) obtained by preparative ultracentrifugation, as well as postheparin lipoprotein lipase activity (H-TGL and LPL) were evaluated in 17 subjects with primary biliary cirrhosis (stage II and III) subdivided into two groups according to the presence or absence of lipoprotein X (Lp-X). A reduction in total lipoprotein lipase activity was observed in both patient groups, compared to controls (P less than 0.01); the hepatic lipoprotein lipase was significantly reduced (P less than 0.01) only in the Lp-X-positive group. The lipid (477.8 +/- 154.3 vs 239.6 +/- 51.1; P less than 0.01) and protein (147.4 +/- 37.1 vs 83.3 +/- 19.7; P less than 0.01) masses in the VLDL + LDL fraction of the Lp-X-positive group were increased compared to controls. In the same group, the HDL2 fraction also showed an increase in lipid (186.6 +/- 80.0 vs 77.9 +/- 21.6; P less than 0.01) and protein (133.9 +/- 60.0 vs 67.9 +/- 16.5; P less than 0.01) masses; in addition, the HDL2 percent lipid composition was different in the two patient groups, showing a decrease in esterified cholesterol (20.4 +/- 3.6 vs 25.7 +/- 2.2; P less than 0.01) and an increase in phospholipids (59.2 +/- 2.9 vs 54.8 +/- 2.6; p less than 0.01) in the Lp-X-positive group.(ABSTRACT TRUNCATED AT 250 WORDS)

Apolipoproteins B↗
PubMed1987

Hepatitis B virus (HBV) in the elderly: an underestimated problem?

Hepatitis B infection in the aged can be underestimated as the clinical and serological pictures can be rather peculiar in these subjects. Institutions for the elderly carry an increased risk of HBV spread as do many other closed communities. People from lower socioeconomic class and from countries with a high HBV prevalence are less susceptible to infection as they are already immunized by previous infections. However, epidemics have been described in homes for the aged, mostly from those for wealthy people or from those in low prevalence countries. When infected the elderly tend to develop a subclinical hepatitis detected only by serum analysis. These infections are frequently followed by asymptomatic chronic carriage of HBsAg. This phenomenon may be due to alterations of the immune system in the aged, which is also suggested by the finding of very poor antibody responses to hepatitis B vaccines in the aged. Overt acute hepatitis is infrequent. It usually have a benign course, even if occasionally cholestatic. Very active type B chronic hepatitis is very rare, while most elderly patients with HBsAg-positive chronic liver disease have cirrhosis as the end stage of chronic hepatitis acquired previously.

Aged↗
PubMed1986

Hepatitis B vaccine: immune response in student nurses. A fifteen-month follow-up.

The authors describe a 15-month follow-up of twenty-nine nurse students vaccinated against hepatitis B with Hevac B Pasteur. At three months all subjects were anti-HBs positive, with a geometric mean titre (GMT) of 1187 mIU/ml. At the time of booster dose (T14) GMT had fallen to 380 mIU/ml; after one month (T15) GMT had risen again to 9332 mIU/ml. Such a high antibody level suggests a long lasting protection.

Adolescent↗
PubMed1985

Detection of two forms of HBeAg (free-and IgG-bound HBeAg) in patients with HBe antigenemia using staphylococcus bearing protein A.

Protein A-bearing Staphylococcus aureus organisms (STA) were used to separate free HBeAg from IgG-bound HBeAg. Free HBeAg was detected in the supernate while IgG-bound HBeAg could be liberated from the pellets using MgCl2 or a glycine buffer. HBeAg was determined by radioimmunoassay and the results expressed as patient's cpm/normal control's cpm ratio (S/N ratio). This ratio was demonstrated to be proportionate to the antigen concentration and used as a titer of HBeAg. Sera of 40 HBsAg-negative healthy volunteers and 82 HBeAg-positive patients who were either asymptomatic HBsAg carriers or had various diseases including chronic persistent hepatitis (CPH), chronic active hepatitis (CAH), and renal disease undergoing hemodialysis, were tested for free HBeAg and IgG-bound HBeAg. Patients with CAH from two different countries were compared. Free HBeAg was detected in all patients but one, IgG-bound HBeAg was detected with similar prevalences (from 56% to 67%) in HBsAg asymptomatic carriers, hemodialysis patients, CPH and Italian CAH patients. In contrast, all CAH patients from New York, who had frequently been exposed to HBV infection, had detectable levels of IgG-bound HBeAg, with the highest S/N ratios observed in the study, and frequently showed an unfavorable outcome. In AVH due to HBV and delta agent co-infection, IgG-bound HBeAg was detected in two of four patients only in the initial stage of the disease. The data reported indicate that a separate determination of free- and IgG-bound HBeAg may have clinical value.

Adolescent↗