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Biomedical subjects

M Colombo

Publications and source records attributed to M Colombo.

At least 325 records · Page 18Linked to original sources
PubMedDate not supplied

A multicenter, prospective study of posttransfusion hepatitis in Milan.

We studied the risk of posttransfusion hepatitis in recipients of blood collected from volunteer donors who tested negative for HBsAg and had serum ALT levels less than 1.5 times the upper limit of the normal range. Between October, 1983 and September, 1984, 676 consecutive patients who needed blood or plasma transfusions during or after elective surgery, who had no history of liver disease and had never received blood previously, were studied. The patients were given a total of 4,813 (mean = 7) units. Ninety-six patients developed posttransfusion hepatitis, which yielded a hepatic incidence of 20 cases per 1,000 units of transfused blood. Ninety-two patients had non-A, non-B hepatitis, 3 had hepatitis B and 1 had cytomegalovirus infection. The incubation periods for non-A, non-B hepatitis ranged from 2 to 26 (mean = 9.5 +/- 4) weeks. In 68 (73%) patients, the hepatitis was completely asymptomatic; only 24 (27%) patients developed symptoms, including jaundice and hepatomegaly. There were no cases of fulminant hepatitis. Sixty per cent of the patients still had elevated serum ALT levels 1 year after the onset of hepatitis. The 96 patients with hepatitis had received a mean of 9.6 blood units, as compared to a mean of 6.7 units for the unaffected patients (p less than 0.001). This study demonstrated that non-A, non-B hepatitis remains a common and important complication of blood transfusion despite screening of blood donors for HBsAg and elevated serum ALT levels.

Adolescent↗
PubMedDate not supplied

Case-control study of hepatitis B virus infection in chronic liver disease and hepatocellular carcinoma.

The prevalence of serum hepatitis B virus markers was studied in three groups of age- and sex-matched patients: a. 31 patients with liver cirrhosis and hepatocellular carcinoma (c-HCC); b. 31 patients with chronic liver disease (CLD) and c. 62 hospitalized control subjects. The overall exposure rate to the hepatitis B virus was 90% in c-HCC, 80% in CLD and 58% in control subjects. The prevalence of hepatitis B surface antigen (HBsAg) was 29%, 13% and 1.6% in the three groups, respectively. The prevalence of hepatitis B surface antibody was significantly lower in c-HCC (9.6%) than CLD (42%) and control subjects (40%). The serological evidence of continuous viral replication (HBsAg positivity or isolated high titre hepatitis B core antibody positivity) was more common in c-HCC (39%) than CLD (12%) and control subjects (1.6%). The prevalence and patterns of aggregation of serum hepatitis B virus markers were similar in the 31 patients with c-HCC and in 11 patients with HCC without concomitant liver cirrhosis (n-HCC). In conclusion, the overall exposure rate to the hepatitis B virus is similar in c-HCC and CLD. However, serological evidence of continuous viral replication is more common in the former group. A defective clearance of the hepatitis B virus in hepatocellular carcinoma is a possible explanation of the phenomenon. The strength of the association between hepatitis B virus infection and hepatocellular carcinoma appears to be similar in c-HCC and n-HCC.

Adult↗
PubMedDate not supplied

R2 anti-reticulin antibody in a mixed hospital population.

R2 anti-reticulin antibody was detected in 15 of the 9,500 serum samples examined (0.16%) from a mixed hospital population. The antibody titre varied from 1:40 to 1:320, and the R2 was of the IgG class in 13 of the 15 positive samples. All the 15 serum samples with R2 were negative on human liver, confirming the lack of cross reaction of this antibody. The reactivity of R2 was not absorbed by soluble fractions of type I collagen, showing that this antibody is not directed against this antigen. R2 was confined to two groups of pathological conditions: connective tissue and digestive tract diseases. Four of 15 patients with R2 had rheumatoid arthritis and in two of these four cases the antibody was of the IgA class.

Animals↗
PubMedDate not supplied

Cryptic hepatitis B virus replication during prednisone therapy in type B chronic active hepatitis.

Hepatitis B virus (HBV) replicating in patients with serum hepatitis B surface antigen and antibody to hepatitis B e antigen (cryptic HBV replication) can be detected by a spot hybridization technique for serum HBV-DNA and by immunoperoxidase staining of hepatitis B core antigen in the liver. These methods allowed us to study the effects of chronic (13 to 82, mean 30 months) administration of low doses (10 or 15 mg/day) of prednisone to 17 patients with chronic active hepatitis and cryptic HBV replication. Liver biopsies performed before treatment demonstrated that 1 to 50% (mean 12%) of the liver cells were infected. After therapy, infected cells had disappeared in 5 (29%), were considerably reduced in 9 (53%) and remained unchanged in 3 (18%) patients. The mean percentage of infected cells in the liver biopsies performed at the end of the follow-up was 3.2 +/- 5.5% (p less than 0.005). Serum HBV-DNA was present in 12 of 13 and in 5 of 12 patients investigated before treatment and at the end of the study, respectively. Five patients harboring HBV in the liver developed cirrhosis during treatment. Our data indicate that, despite steroid therapy, HBV replication either ceased or was decreased in two thirds of the patients, while in no case it flared-up. The rise of cirrhosis was not prevented by this type of therapy.

Chronic Disease↗
PubMedDate not supplied

Serum procollagen type III peptide levels in patients with acute viral hepatitis.

Serum levels of procollagen type III peptide were measured by radioimmunoassay in 76 consecutive patients with acute viral hepatitis, in order to see if this index of hepatic fibrogenesis is also predictive for the development of chronic active hepatitis in high-risk patients. Serum procollagen levels were high (from 14.2 to 109.2 ng/ml, median 33.7 ng/ml) in 74 (97%) patients and normal (from 4 to 14 ng/ml, median 9.1 ng/ml) in 2 (3%) patients. The baseline serum procollagen levels were similar in all the subgroups of patients independently of the type of hepatitis. In the 59 patients with resolving hepatitis, serum procollagen levels returned to normal values from 2 to 48 weeks (mean 15). In the 17 patients with unresolved hepatitis, procollagen levels remained within the normal limits in 6 of 7 patients with non-progressive chronic disease, while were elevated (from 17.4 to 22.2 ng/ml) in 4 of 5 patients with chronic active hepatitis. Unlike transaminase activity, which could not discriminate between benign and progressive liver disease, serum levels of procollagen helped in identifying patients with unresolved hepatitis, who were developing chronic active disease.

Acute Disease↗
PubMedDate not supplied

Anti-LAV/HTLV-III antibodies in groups of individuals at high risk for infection in Italy.

We have studied anti-LAV/HTLV-III antibody prevalence in individuals at high risk for infection, such as intravenous drug addicts, hemophiliacs and homosexual men. Among intravenous drug addicts, LAV/HTLV-III infection was first recognized in 1981 and positive serum reactions for anti-LAV/HTLV-III antibody rose in successive years to 53%. Anti-LAV/HTLV-III antibody prevalence was 13.5% in the group of homosexual men, while in hemophiliacs treated with commercial concentrates it was 37% in 1984 and had increased to 45% in 1985. There was a significant correlation between antibody status and concentrate consumption in these patients. Results of studies of anti-LAV/HTLV-III antibody patterns with the Western blot technique suggest that antibodies against core proteins (mainly p25 and p18) and the envelope protein gp40 are always present in asymptomatic individuals and in patients with the lymphadenopathy syndrome, but usually not in patients with full-blown AIDS. These last patients have typical positive reactions only against the envelope proteins gp110 and gp40.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Dendritic development in neocortex of infants with early postnatal life undernutrition.

The structure of large pyramidal cells from layer V of the motor cortex of undernourished and well-nourished infants was studied to determine the effects of postnatal nutrition on cortical dendritic development. In undernourished infants, the arborization and span of the basilar dendrites were decreased in comparison to controls. These findings indicated that undernutrition experienced during the first months of postnatal life could affect the growth of pyramidal cells, especially the formation of basilar dendrites.

Bronchopneumonia↗
PubMedDate not supplied

Direct detection of HBV preC mutants in heterogeneous viral populations by a modified DNA sequencing method.

A modified method for the direct sequencing of double-stranded DNA products of PCR amplification is described and has been applied to the analysis of hepatitis B virus (HBV) preC/C region in samples from persistently infected patients with chronic hepatitis. Data was obtained from both hepatitis B e antigen (HBeAg)-positive and -negative chronic carriers. A high prevalence of mixed viral populations (wild-type genomes and mutated sequences with a TAG stop codon in the distal preC region at position 1895-1897) was shown in the HBeAg-positive group; a homogeneous (either mutated or wild-type) viral population was detected in all but one of the long-term HBeAg-negative, untreated chronic carriers, thus suggesting that pre-core mutants can be rapidly generated and selected during the natural course of HBV infection.

Base Sequence↗
PubMedDate not supplied

High prevalence, low pathogenicity of hepatitis G virus in kidney transplant recipients.

BACKGROUND: Prevalence and pathogenicity of hepatitis G virus infection in long-term renal transplant recipients, are not fully known. AIM: To evaluate long-term impact of HGV infection on liver disease of renal transplanted patients. PATIENTS AND METHODS: A total of 155 hepatitis B surface antigen negative kidney transplant recipients, followed for a mean of 11 years after renal transplantation, were studied. Of these 48 (31%) patients had persistently elevated serum aminotransferase values. Frozen serum samples were tested for HGV-RNA and HCV-RNA by nested reverse transcribed polymerase chain reaction, and for anti-hepatitis G virus and anti-hepatitis C virus by enzyme-linked immunosorbent assay Hepatitis C virus-RNA was typed by a line probe assay and quantified by a branched DNA signal amplification assay RESULTS: Hepatitis G virus-RNA was detected in 37 (24%) patients and anti-hepatitis G virus in another 26 (17%). Seventy (45%) patients had serum anti-hepatitis C virus and 63 of these (90%) had serum hepatitis C virus-RNA. Hepatitis G virus-RNA positive and negative patients were similar in terms of age, sex, duration of dialysis, rate of transfusion, chronic liver disease, rate of hepatitis C virus infection and immunosuppressive therapy. Fifteen (41%) hepatitis G virus-RNA seropositive patients were hepatitis C virus co-infected. Hepatitis C virus-RNA levels were significantly lower in the 15 hepatitis C virus/hepatitis G virus co-infected patients than in the 48 patients with hepatitis C virus infection only (2.2 vs 10.8 MEq/ml, p = 0.02). Only 3 hepatitis G virus carriers had persistently elevated alanine aminotransferase compared to 29 hepatitis C virus carriers (14% vs 60%, p < 0.001), 10 patients co-infected with both hepatitis G virus and hepatitis C virus, and in 6 patients with neither infection (67% vs 8%, p < 0.001). CONCLUSIONS: Hepatitis G virus infection is common among kidney transplant patients, it carries a low risk of chronic liver disease even in long-term follow-up. Low levels of hepatitis C virus-RNA found in hepatitis G virus carriers suggest an interaction between these two viruses in immunosuppressed patients.

Adult↗
PubMedDate not supplied

Characterization of small combinatorial chemistry libraries by (1)H NMR. Quantitation with a convenient and novel internal standard.

A novel silane standard, 1,4-bis(trimethylsilyl)benzene (BTMSB), is introduced for the generic quantitation of small organic molecules in DMSO-d(6) solution by (1)H NMR. This standard is an easily weighable solid and is stable for at least 1 month in DMSO solution, and its (1)H NMR spectrum contains a strong singlet in a region usually free of signals. With a set of certified standards, concentration determination with about 2% precision and accuracy is verified after solution preparation with fully automated procedures, thus making very effective the characterization of small combinatorial chemistry libraries for identity and purity when combined with other physicochemical or biochemical tests. As an example, for a set of about 400 compounds, results of (1)H NMR characterization are compared to the more customary LC-UV-MS method. NMR and MS data agree for identity on the vast majority of cases (84% positive and 5% negative), whereas the remaining cases (11%) are marked as highly impure only after NMR spectra analysis. Most importantly, determination of concentration rather than that of relative purity appears the right choice for a correct evaluation of biochemical potency.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Asymptomatic hepatitis G virus infection in blood donors.

BACKGROUND: Hepatitis G virus (HGV) has been reported in patients with fulminant hepatitis and aplastic anemia, but HGV RNA has also been found in healthy individuals. The possible associations of HGV with liver function and hematologic abnormalities in asymptomatic blood donors were investigated. STUDY DESIGN AND METHODS: Serum HGV RNA was determined in 200 repeat donors (Group A), 44 subjects with elevated alanine aminotransferase (Group B), and 54 hepatitis C virus carriers (Group C). Liver histology was evaluated in Group C by using the histologic activity index. RESULTS: HGV RNA was detected in three subjects of Group A (1.5%; 95% CI: 0.3-4.3), two of Group B (4.5%; 95% CI: 0.6-15.5%), and six of Group C (11.1%; 95% CI: 4.2-22.6). The prevalence of leukopenia and elevated gamma-glutamyl transpeptidase was higher in the 11 viremic donors than in 88 nonviremic subjects (36% vs. 2.3%, and 55% vs. 22%, respectively; p < 0.05), matched for clinical and demographic characteristics. The mean histologic activity index score +/- standard error was 4 +/- 0.7 in the HGV RNA-positive donors and 3.4 +/- 0.3 in the HGV RNA-negative donors. CONCLUSION: HGV is endemic in Italian blood donors, although it has a limited role in causing liver damage. Further studies are needed to clarify its role in inducing transfusion-associated disease in myelosuppression.

Adult↗
PubMedDate not supplied

Prevalence and genetic variants of hepatitis GB-C/HG and TT viruses in Gabon, equatorial Africa.

The distribution of Hepatitis GB-C/HG (GB-C/HG) and TT viruses (TTV) infections was investigated in selected populations from Gabon using Polymerase Chain Reaction (PCR) and Enzyme Linked Immunosorbent Assay (ELISA) for anti-Envelop 2 (anti-E2) GBV-C/HGV antibodies. Among pregnant women, 29 of 229 (12.6%) were Hepatitis GB virus-C and Hepatitis G virus (GBV-C/HGV) RNA positive (+) and 32 of 81 (39.5%) anti-E2 + versus 8 of 39 (20.5%) TTV DNA +. Among sickle cell anemia patients, 9.7% (3/31) were GBV-C/HGV RNA + versus 22.5% (7/31) TTV DNA +. For tuberculosis patients, the figures were 11.5% (4/35) and 0%. A study of hepatocellular carcinoma cases (n = 27) versus controls (n = 66) did not show significant differences for GBV-C/HGV RNA (10.7% versus 12.1%) and TTV DNA (44.4% versus 30.3%). According to phylogenetic analysis, the 15 GBV-C/HGV strains investigated clustered in group 1, the most common in sub-Saharan Africa whereas TTV sequences (n = 4) mostly clustered in genotypes G1 and one close to genotype G3. In the Gabonese populations investigated, GBV-C/HGV and TTV infections were highly endemic. These data are consistent with the low pathogenicity of these agents.

Adult↗
PubMedDate not supplied

Nonpercutaneous therapies of hepatocellular carcinoma.

Treatment of hepatocellular carcinoma depends largely on local resources, the stage of the disease and the presence of cirrhosis, but is limited overall by the lack of efficient chemotherapy. Hepatic resection is the treatment of choice for the few patients with hepatocellular carcinoma and normal liver. Five-year survival without recurrence in patients with a tumor of mean diameter 8 cm was 33%. Liver transplantation is the best chance for cure in patients with cirrhosis and a single small tumor, but its widespread application is limited by a number of obstacles, including cost. Tumor size and number, and liver status were common guidelines for selecting patients. Five-year survival of transplant patients was > 50%, compared to 0% in historical untreated controls. Patients with well-preserved liver function and a small tumor at the periphery could equally benefit from hepatic resection, although cirrhosis entails the risk of morbidity due to portal hypertension and development of de-novo tumors. Another major drawback of hepatic resection is the early spread of tumor cells, facilitating early tumor recurrence after operation. For patients with compensated cirrhosis and a small tumor who were hardly eligible for surgery, transcatheter arterial chemoembolization appeared to be a cost-saving and effective treatment modality. Transcatheter arterial chemoembolization has been largely employed also for the palliative treatment of patients with large tumors, but the benefits on survival are doubtful. Conventional radiotherapy with external irradiation was not effective against hepatocellular carcinoma.

Carcinoma, Hepatocellular↗