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Biomedical subjects

F Bonino

Publications and source records attributed to F Bonino.

At least 127 records · Page 7Linked to original sources
PubMed1992

Hepatic endoplasmic reticulum storage diseases.

Endoplasmic Reticulum Storage Diseases (ERSD) represent a novel group of inborn errors of metabolism affecting secretory proteins and resulting in hepatocytic storage and plasma deficiency of the corresponding protein. The hepatocellular storage is due to a molecular abnormality hindering the translocation of the abnormal protein from the rough (RER) to the smooth endoplasmic reticulum (SER). The molecular abnormality is genetically determined; hence it is hereditary, congenital, familial and permanent. The storage is selective and exclusive for the mutant protein and predisposes to the development of chronic cryptogenic liver disease. ERSD include alpha-1-antitrypsin deficiency, fibrinogen storage and alpha-1-antichymotrypsin deficiency. Basically, the diagnosis of ERSD is a morphological one: immunohistochemistry and electron microscopy are essential tools for their identification.

Afibrinogenemia↗
PubMed1992

Detection of cytomegalovirus by in situ hybridization using a digoxigenin-tailed oligonucleotide.

A non-isotopic in situ hybridization procedure was used to detect cytomegalovirus (CMV) sequences within routinely fixed tissue. A digoxigenin-tailed oligonucleotide was hybridized to sections of specimens obtained at autopsy from 2 patients with CMV infection. Hybrids were revealed by an alkaline phosphatase-conjugated anti-digoxigenin antibody. Serial sections were also assayed for the presence of CMV by in situ hybridization with a biotin-labelled cDNA probe and by immunohistochemistry and routinely stained for morphological evaluation. Results show that the two in situ hybridization procedures are equally sensitive but superior to the immunohistochemical detection of the viral antigen. Most cells positive for CMV DNA had the cytopathological features characteristic of CMV infection. A minor population of infected cells lacking morphological changes was also found. We recommend the routine application of the oligonucleotide-based assay because it is specific, easy and less expensive than other similar procedures.

Alkaline Phosphatase↗
PubMed1992

From immunohistochemistry to in situ hybridization.

The revolutionary evolution in science and technology has made it possible to face adequately three main challenges in modern medicine: old diseases changing, new diseases appearing, diseases remaining unknown. In this paper we review the road travelled by the pathologist in search of a method which is based upon the application to routine work of instruments and techniques which once were available for research only. Application to tissue studies of immunological and molecular biology techniques allows a dynamic interpretation of biological phenomena with special regard to gene regulation and expression. The method implies stepwise investigations, including immunohistochemistry, EM and in situ hybridization, in order to progress from the suggestive features detectable in routinely stained preparations to more characteristic, specific and, finally, pathognomonic features. HE-stained preparations and appropriate immunohistochemical stains enable recognition of phenotypic changes which may reflect genotypic alterations. Thus there is a logical and methodological link between the simple HE and the most powerful techniques so far introduced in pathology: immunohistochemistry and in situ hybridization.

History, 20th Century↗
PubMed1992

Antibodies to hepatitis C virus in kidney transplantation.

Ninety patients on dialysis, 241 cadaveric kidney donors and 27 cadaveric kidney recipients with a follow-up of 2 years, have been investigated as for anti-HCV positivity by means of 3 tests. As for patients on dialysis and cadaveric donors, the prevalence was 32 and 4%, respectively. As for transplanted patients, it must be noted that 4 negative recipients from positive donors seroconverted, but without any change in hepatic enzymes, while in 2 or 9 anti-HCV-positive recipients, hepatic enzymes increased after transplantation. Seroconversion in patients transplanted from a negative donor was not significantly different. We conclude that, according to their experience, anti-HCV positivity in the donors is not associated with a significant risk of infection in recipients of cadaveric grafts.

Adult↗
PubMed1992

In situ hybridization in viral hepatitis.

In situ hybridization (ISH) is a sensitive and specific technique for detecting nucleic acids in intact cells. Visualization of the target sequences by autoradiography or immunohistochemistry allows their precise subcellular localization and quantitation. The application of ISH techniques has contributed to the understanding of the complex replicative cycle of hepatitis B virus. More recently, hepatitis delta and C virus replication has also been studied by this technique. ISH-based assays have finally been used to follow the replication of cytomegalovirus within the transplanted liver. Although ISH is a powerful tool for the molecular biologist, its clinical significance in the diagnosis and prognosis of human hepatitis virus infections has yet to be fully evaluated.

Hepacivirus↗
PubMed1992

Treatment of chronic hepatitis B with beta interferon given intramuscularly: a pilot study.

In a pilot study aimed to test the therapeutic potential of beta interferon (IFN) given intramuscularly we treated 4 patients with HBeAg positive chronic hepatitis B with a progressively increased dosage of beta IFN (from 5 to 9 million units daily) for 1 month and with 9 million units for 5 additional months, thrice weekly. In 3 of the 4 patients, serum HBV-DNA decreased during therapy and remained undetectable in 2 who seroconverted from HBeAg to anti-HBe while in 1 patient viraemia rebounded to pretreatment levels during the follow-up. In the remaining patient serum HBV-DNA fluctuated during treatment. These results suggest that beta IFN given intramuscularly has a potential therapeutic efficacy in patients with chronic hepatitis B and prompt further clinical trials in a larger number of patients.

Adult↗
PubMed1992

Treating chronic liver disease: lessons from a day hospital.

The relationship between the professional background of the physician requesting the biopsy procedure (whether non-specialist or specialist in hepatology/gastroenterology) and the subsequent decision of treatment of the patients was analyzed. Treatment was divided into two categories named arbitrarily "no therapy" (general supportive measures) or "therapy" (causal treatment based on active drugs or measures aimed at affecting the cause of the disease). Of the 204 cases of outpatient needle biopsies available for study, 157 were made by specialist request and 47 were made by a non-specialist request. Sixty-eight (43%) of the former, but only 3 (2%) of the latter had "therapy" (p = 0.0001). Also, patients in which histology showed chronic active liver disease had "therapy" more frequently (49 of 109, 44.9%) than those without chronic active liver disease (22 of 95, 23%) with p less than 0.01. However, patients with histological active chronic disease were not more frequent among specialist requests (56.6%) than among the non-specialist requests (42.5%). But among patients attended by the specialist, there were more patients (31.8%) with positive serum markers of Hepatitis B virus infection than among those sent by others (12.7%) with p less than 0.01. We conclude that at least in the premises in which this study was carried out, blind liver biopsies will lead to active treatment more often in patients treated by a specialized physician, because these patients are more likely to have a virus identified as the cause of their liver disease and consequently will receive antiviral treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[The relationships between the lipoprotein profile and rheological-coagulation parameters in patients with hyperlipoproteinemia type II].

The aim of the study was to evaluate the direct influence of lipid parameters (total and HDL-cholesterol, triglycerides and total lipids) on the rheologic-coagulative pattern. We studied blood rheological properties--blood (BV), plasmatic (PV), and seric (SV) viscosity, whole blood (WBF) and red cell (RCF) filterability--and some coagulative factors--fibrinogen (Fib), levels of clotting factor VII (fVIIc) and VIII (fVIIIc) activity--in 156 men aged 40-54 years; 87 patients had type II hyperlipoproteinemia (46 type IIa and 41 type IIb) and 69 were normolipemic controls. Smokers, patients with arterial hypertension, diabetes mellitus or cardiovascular clinical manifestations were excluded. Type IIb hyperlipoproteinemic patients had increased blood viscosity (shear rate 225 sec-1, p. less than 0.01), which was positively correlated with triglycerides and fibrinogen concentration. Levels of fibrinogen, fVIIc and fVIIIc activity did not differ significantly in hyperlipemic patients and controls, although fVIIc activity and fibrinogen were both positively related with lipid parameters. These data suggest that, in absence of other major risk factors, the alterations of the rheologic-coagulative pattern are mainly dependent on the severity of the lipid disorder.

Adult↗
PubMed1991

Role of hepatitis delta virus infection in hepatocellular carcinoma.

Hepatitis B virus (HBV) DNA integrates into the host DNA and shows a series of potentially oncogenetic properties, but HBV is not an acutely transforming virus, because HCC develops decades after infection. Other factors, namely cirrhosis, inflammation, alcohol intake, and viral superinfections, could promote the oncogenetic process induced by HBV-DNA integration. We studied the impact of HDV infection in the pathogenesis of HCC in 62 consecutive patients. Their mean age was 59 years (range 25-75 years), 54 were male and eight female; 58 had cirrhosis. The findings suggest that HBsAg-positive patients with HDV superinfection developed cirrhosis and HCC at an earlier age than HBsAg carriers without HDV infection. HDV appears to represent a "promotion" factor for HCC in subjects with an oncogenic risk induced by HBV. A long-lasting necroinflammatory lesion of the liver substained by productive HBV and HDV infections may be a major pathogenetic mechanism.

Carcinoma, Hepatocellular↗
PubMed1991

Variable and hypervariable domains are found in the regions of HCV corresponding to the flavivirus envelope and NS1 proteins and the pestivirus envelope glycoproteins.

Based on the flavi- and pestivirus model of genome organization for the hepatitis C virus (HCV) (1-5), the nucleotide and deduced amino acid sequences of the putative envelope (E1) and the junction between the E1 and NS1/envelope 2 (E2) region from six different human isolates of HCV were compared with the nucleotide and predicted amino acid sequences of the prototype hepatitis C virus (HCV-1) (5). The overall percentage of nucleotide and amino acid changes among all six isolates, including HCV-1, from nucleotide 713 to 1630 (amino acid 129 to 437) was between 3 and 7%, which is comparable to that seen in some flaviviruses (6-8). An analysis of the number of nucleotide and deduced amino acid sequence changes among all six isolates and HCV-1 revealed a moderately variable domain of approximately 40 amino acids in the E1 region and a hypervariable domain (Region V) of approximately 28 amino acids, which is directly downstream from a putative signal peptide sequence, in the junction between E1 and NS1/E2. A similar hypervariable domain is not found in the C-terminus of the envelope polypeptide or in the N-terminus of the NS1 polypeptide domain of the flaviviruses. These findings suggest that the mature NS1/E2 polypeptide starts about amino acid 380 and that the NS1/E2 domain may correspond to a second envelope glycoprotein as in the case of the pestivirus. The observed heterogeneity in the putative structural proteins of HCV may have important ramifications for future vaccine development.

Amino Acid Sequence↗
PubMed1991

Replicating and virion secreting hepatitis B mutant virus unable to produce preS2 protein.

Mutant HBV genomes unable to produce preS2 protein were identified in the serum of a highly viremic chronic carrier. By direct sequencing of the amplified preS region and by sequencing of 50 cloned amplified preS DNA fragments all molecules were found to have deleted the preS2 translation initiation codon and three amino acids 54 nucleotides downstream thereof. In addition, numerous amino acid changes, predominantly located between both deletions, were revealed. HBV-DNA genomes containing the mutated preS sequences were shown to be replication competent and to secrete efficiently virions that were morphologically and by the type of DNA encapsidated not distinguishable from wild-type virus. These data demonstrate that HBV with mutated preS sequences and unable to express preS2 protein can occur as a dominant or exclusive virus population in a highly viremic chronic carrier. The data also show that expression of the preS2 protein is not essential for HBV replication, virion morphogenesis and secretion.

Adult↗
PubMed1991

Hepatitis delta virus heterogeneity: a study by immunofluorescence.

Hepatitis delta virus (HDV)-RNA shows a microheterogeneity at nucleotide 1015 resulting in the production of two co-terminal forms of the HDV-associated antigen (HDAg), referred to as p24 and p27. In vitro experiments have shown that p24 is localized within the nucleolus, while p27 expression is probably confined to the nucleoplasm. The sequential appearance of these two proteins may play a role in the HDV-induced cell damage. We have examined 12 formalin-fixed human liver biopsies taken at different phases of the natural course of HDV infection. Specimens were assayed for HDAg by direct immunofluorescence with a human IgG reactive towards both p24 and p27. Positive cells were then examined for cytopathological features after hematoxylin/eosin staining. All biopsies contained intranuclear HDAg. However, three different patterns of fluorescence were seen: (1) nucleolar with weak nucleoplasmic; (2) homogeneous nucleoplasmic with negative nucleolus; (3) intense fluorescence diffuse to the whole nucleus. Pattern 1 was found in 15-50% of positive nuclei of all samples, irrespective of the phase of infection, while the remaining positive nuclei mostly showed another pattern (2) of fluorescence. Neither pattern was associated with cytoplasmic eosinophilia. Degenerated hepatocytes, when infected (5%), showed pattern 3 of HDAg fluorescence but were mostly negative for HDV. Therefore, the intranuclear distribution of HDAg, as assayed in vivo, does not seem to correlate with peculiar phases of HDV infection. Different phases of the viral life style, instead, are asynchronously represented within each liver sample.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Viral↗
PubMed1991

Rabbit-derived anti-HD antibodies for HDAg immunoblotting.

We studied the sensitivity and specificity of two rabbit-derived antibodies (W2 and W3) raised against two synthetic peptides of the HDAg: the C-terminus of the p24 protein (W2) and the C-terminus of the p27 protein (W3) (Chiron Co., Emeryville, CA, U.S.A.). The results were compared with those obtained with a human polyclonal anti-HD (W1). We have tested W2 and W3 against blotted serum samples from 25 patients (20 HBsAg positive anti-HD positive, three HBsAg positive anti-HD negative and two HBsAg negative anti-HD negative) and liver extracts from five HBsAg seropositive patients, two anti-HD positive and three anti-HD negative. In serum samples W3 sporadically reacted with a p31 protein present in both anti-HD positive and negative sera; W2 identified the p24 protein in 7/10 W1 positive samples but in none of 10 W1 negative; the p27 protein was captured by W2 only in one highly viremic serum. In every sample of liver extract W3 recognized a 48-kDa band. W1 and W2 stained 5 bands at 45, 27, 24, 16 and 12 kDa. The p45, p27 and p24 proteins were peculiar of HDV-infected livers; p16 and p12 were also detected in HDV free livers. W2 identified an additional 54-kDa protein in 4/5 liver extracts. For diagnostic purposes human polyclonal anti-HD represents the most sensitive probe for HDAg immunoblotting, with a specificity similar to that of rabbit-derived antibodies. The affinity of W2 and W3 antibodies for serum and liver HDAg appears to be lower than for HDAg recombinant.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗