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Biomedical subjects

F Bonino

Publications and source records attributed to F Bonino.

At least 109 records · Page 6Linked to original sources
PubMed1993

Is high AgNOR quantity in hepatocytes associated with increased risk of hepatocellular carcinoma in chronic liver disease?

AIMS: To evaluate whether high numbers of silver staining nucleolar organiser regions (AgNORs) in hepatocytes are associated with increased risk of hepatocellular carcinoma in chronic liver disease. METHODS: The quantitative distribution of AgNORs was studied in the liver biopsy specimens of 33 patients with chronic liver disease, 11 of whom developed hepatocellular carcinoma. The interval between liver biopsy and diagnosis of hepatocellular carcinoma was 26 months (range one to 61 months); the mean follow up of patients without hepatocellular carcinoma was 45 months (range 24-59 months). Quantitative evaluation of AgNORs was carried out on silver stained routine sections by morphometric analysis, using a computer assisted image analysis system. RESULTS: High interphase AgNOR values (> 3 microns2) were found in hepatocytes of nine out of the 11 (82%) patients in whom neoplastic transformation occurred. Of the remaining 22 patients, only seven (31%) had AgNOR values higher than > 3 microns2 (chi 2 4.83; p = 0.036). CONCLUSIONS: These results indicate that high numbers of interphase AgNORs are associated with increased risk of hepatocellular carcinoma in patients with chronic liver disease.

Adult↗
PubMed1993

[Influence of sex, age, and profession on transient work disability at a health center].

OBJECTIVE: To analyse whether the variables of gender, age and type of job of those in full-time work affect short-term unfitness for work (SUW) in a study undertaken within our health area. DESIGN: A prospective and retrospective study of all the SUW. SETTING: Primary Care. An urban Health Centre. PARTICIPANTS: Those people with full-time jobs registered at the Centre. MAIN MEASUREMENTS AND RESULTS: The entire 1098 certificates of SUW issued in 1990 were processed. The population pyramid and job distribution among those in full-time work was obtained by a random sample of 5% of the active population. When time off for maternity (TOM) was excluded, women accounted for 44.8% of SUW and men 55.2%. There were no significant differences with the percentages these figures represent for the active population as a whole. The number of SUW per 100 people in work was 15.9 for men and 21.5 and 17.4 for women (including and excluding TOM, respectively). The average length of SUW, excluding maternity, was 27.06 days for men and 26.8 for women. On the question of age, those under 19 and over 40 contributed least to the SUW percentage. Additionally, those under 19 and over 60 were the proportions of the population least prone to SUW. On the question of type of job, we found a higher contribution to absenteeism than expected within Groups 3 and 4 and less in Groups 0/1, 5 and 7/8/9. The longest average length of time for SUW was in Group X (84.2 days/SUW). CONCLUSIONS: Excluding TOM, gender does not appear to be a variable that affects SUW. Age group and type of job are variables affecting SUW. It will be necessary to undertake research into whether there are additional social or labour factors which might explain.

Absenteeism↗
PubMed1993

Hepatitis delta virus pathogenicity.

This review has presented data consistent with the hypothesis that HDV may be directly cytopathic or non-cytopathic depending on the stage of infection. Nevertheless, although a majority of HDV-infected patients show evidence of liver disease, healthy carriers of the virus lead to the suggestion that different healthy carriers of HDV can exist, but particularly in the absence of a florid HBV replication. These results lead to the suggestion that different strains of HDV may result in different disease outcomes. Furthermore, the role of HBV in the pathogenetic process is unlikely to be passive, and some effort should be made to examine carefully the effects of the interplay between HBV variants and HDV and the course and pathogenicity of HDV infection (see Brunetto, this volume).

Animals↗
PubMed1992

Essential role of collagens for terminal differentiation of preadipocytes.

In order to study the role of collagens in the differentiation of TA1 preadipose cells in vitro, ethyl-3,4-dihydroxybenzoate (EDHB) was used as a specific inhibitor of collagen synthesis. The secretion of collagenous proteins only was severely decreased after exposure to EDHB, and this was accompanied by a decrease of differentiation as indicated by low activity levels of glycerophosphate dehydrogenase. The effect of EDHB was dose-dependent and also dependent upon the stage of cell differentiation. Northern-blot analysis show that EDHB addition to undifferentiated cells did not prevent the induction of A2COL6 gene, a marker of the preadipose state, but prevented the induction of the gene encoding for the adipocyte lipid binding protein and the modulation of the expression of the lipoprotein lipase gene which are both indicators of the adipose state. These results demonstrate that differentiation of preadipose cells into adipose cells requires active synthesis of collagens during the preadipose state.

Adipose Tissue↗
PubMed1992

Evidence for immune selection of hepatitis C virus (HCV) putative envelope glycoprotein variants: potential role in chronic HCV infections.

E2/nonstructural protein 1, the putative envelope glycoprotein (gp72) of HCV, possesses an N-terminal hypervariable (E2 HV) domain from amino acids 384 to 414 of unknown significance. The high degree of amino acid sequence variation in the E2 HV domain appears to be comparable to that observed in the human immunodeficiency virus type 1 gp120 V3 domain. This observation and the observation that the HCV E2 HV domain lacks conserved secondary structure imply that, like the V3 loop of human immunodeficiency virus 1 gp120, the N-terminal E2 region may encode protective epitopes that are subject to immune selection. Antibody-epitope binding studies revealed five isolate-specific linear epitopes located in the E2 HV region. These results suggest that the E2 HV domain is a target for the human immune response and that, in addition to the three major groups of HCV, defined by nucleotide and amino acid sequence identity among HCV isolates, E2 HV-specific subgroups also exist. Analysis of the partial or complete E2 sequences of two individuals indicated that E2 HV variants can either coexist simultaneously in a single individual or that a particular variant may predominate during different episodes of disease. In the latter situation, we found one individual who developed antibodies to a subregion of the E2 HV domain (amino acids 396-407) specific to a variant that was predominant during one major episode of hepatitis but who lacked detectable antibodies to the corresponding region of a second variant that was predominant during a later episode of disease. The data suggest that the variability in the E2 HV domain may result from immune selection. The findings of this report could impact vaccine strategies and drug therapy programs designed to control and eliminate HCV.

Amino Acid Sequence↗
PubMed1992

Detection of intrahepatic replication of hepatitis C virus RNA by in situ hybridization and comparison with histopathology.

A nonisotopic in situ hybridization (NISH) assay was used to detect hepatitis C virus (HCV) RNA. A synthetic oligonucleotide complementary to bases 252-301 of the highly conserved 5' noncoding region of the HCV genome was end-labeled by terminal deoxynucleotidyltransferase using digoxigenin-conjugated dUTP. The hybridized oligomer was revealed by an immunohistochemical reaction after incubation with an alkaline phosphatase-conjugated anti-digoxigenin antibody and subsequent amplification with a complex of alkaline phosphatase and anti-alkaline phosphatase antibodies. The intracellular distribution of HCV RNA was monitored in the livers of two chimpanzees experimentally infected with the H strain of HCV and compared with the serum alanine aminotransferase activity, serum HCV RNA, and liver histopathology. Most cells were stained in the cytoplasm as early as 2 days after inoculation, 1 and 2 days, respectively, before the appearance of viral RNA in the serum. The time course of HCV RNA replication was correlated with increases in serum alanine aminotransferase. However, neither one paralleled the appearance of liver cell necrosis nor showed any correlation with the inflammatory response. The NISH signal was not found in liver biopsy specimens taken from these two animals before inoculation with HCV, from chimpanzees with acute hepatitis type A, B, or delta, or from two animals never experimentally infected with any hepatitis agent; moreover, it disappeared when the positive specimens were predigested with RNase and it was not observed after hybridization of positive controls with a labeled oligomer unrelated to HCV RNA. Thus, detection of liver HCV RNA by NISH is a sensitive and specific method for studying HCV replication at the cellular level. Intracellular replication of HCV did not appear to be associated with histopathologic changes in the liver, although the correlation with increases of liver enzyme activity in the serum suggested possible damage to the liver cell membrane.

Alanine Transaminase↗
PubMed1992

Variants of hepatitis B virus.

Variations in the course of disease caused by hepatitis B virus may often be attributed to genomic variants of the virus. It must be kept in mind, however, that other factors, i.e. immunocompetence of the host and new methods of detection such as PCR, may also result in apparently aberrant phenotypic expression. Examples of both situations are presented here and the need is stressed for combined virological, biochemical and clinical studies.

DNA, Viral↗
PubMed1992

Detection of hepatitis delta virus RNA by a nonradioactive in situ hybridization procedure.

A digoxigenin-tailed, synthetic oligodeoxynucleotide was used to detect genomic hepatitis delta virus (HDV) RNA in formalin-fixed, paraffin-embedded liver sections by a nonisotopic in situ hybridization (NISH) procedure. Twenty-three liver samples from chronically HDV-infected patients were studied. Eight liver specimens from humans and chimpanzees without markers of active HDV infection served as negative controls. In three samples, the NISH findings were compared with characteristic nuclear features and with the distribution of the HDV encoded antigen, HDAg, as detected by direct immunofluorescence. All samples from HDV-infected patients were positive for HDV RNA by NISH. The viral genome was exclusively observed within the hepatocytic nuclei. No enzymatic reaction was detected after hybridization with the negative controls. "Sanded" nuclei, a cytopathologic change associated with HDV infection, were HDV RNA-positive, but only a small percentage of infected cells showed that feature. Hepatocytes containing the HDV RNA were sometimes binucleated or exhibited giant nuclei. When HDAg and HDV RNA were sequentially detected within the same sections, the localization of the viral antigen almost completely overlapped with the expression of the HDV transcripts, and vice versa. In conclusion, detection of intrahepatic HDV RNA by NISH is a rapid, sensitive, and specific technique that is easily applicable to routine histopathology and allows correlation of HDV with the morphology of hepatocyte nuclei.

Antigens, Viral↗
PubMed1992

The epidemiology of hepatitis delta infection in Italy. Promoting Group.

The epidemiology of HDV infection in Italy was assessed in a retrospective study involving 1556 HBsAg chronic carriers on their first presentation at one of the 35 Liver Units in 1987. Total anti-HD was detected in 23.4% of HBsAg carriers and was significantly more frequent in southern than in northern Italy (26.6% vs. 19.1%, p less than 0.01). Age distribution showed that 73% of the anti-HD-positive subjects, but only 56% of the anti-HD-negative subjects, were under 40 years of age (p less than 0.01). Anti-HD prevalence increased with the severity of the liver disease from 3.8% in healthy carriers to 42.5% in cirrhosis. No geographical statistical difference was found among HBsAg healthy carriers or subjects with chronic persistent hepatitis (CPH), while among patients with chronic active hepatitis (CAH) or cirrhosis anti-HD prevalence was much higher in the south (p less than 0.01). The various potential risk factors were evaluated by multiple logistic regression analysis. HDV infection was independently related to young age, residence in the south, i.v. drug abuse, a large family and household contact with an anti-HD-positive carrier. No association was found with blood transfusion or male homosexuality. These findings confirm that HDV infection is endemic in Italy, particularly in some southern areas, where intrafamily contact probably at a young age may favour the spread of the infection.

Adolescent↗