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Biomedical subjects

A Smedile

Publications and source records attributed to A Smedile.

At least 73 records · Page 4Linked to original sources
PubMed1990

Riboprobe assay for HDV RNA: a sensitive method for the detection of the HDV genome in clinical serum samples.

We have used a new hybridization assay for the detection of the genome of hepatitis delta virus (HDV) in serum using a strand-specific RNA probe obtained by transcription of a recombinant riboprobe. This assay was tested on a panel of 30 sera from HBsAg carriers with hepatitis delta antigen (HDAg) in the liver. The riboprobe assay detected HDV RNA in the serum of 83% of the patients, while 63% were positive using the DNA hybridization assay. HDAg was detected in 73% of the same sera by immunoblotting. The riboprobe assay was also compared to other assays on serial samples from an experimentally infected chimpanzee. These results demonstrate that the Northern blot assay using the RNA probe is more sensitive than the homologous DNA probe for the detection of HDV in serum and is also more sensitive than the immunoblot assay for HDAg. The riboprobe assay is the most sensitive of currently available methods to measure HD viremia.

Adult↗
PubMed1990

Monomeric (7S) immunoglobulin M antibodies to hepatitis delta virus in hepatitis type D.

The pattern of the immunoglobulin M antibody to the hepatitis delta virus distinguishes acute from chronic hepatitis D. Expression of the immunoglobulin M antibody to the hepatitis delta virus is relatively weak and short-lived in self-limited hepatitis but strong and persistent in chronic forms. To study the nature of the immunoglobulin M antibody to the hepatitis delta virus in acute hepatitis D and in chronic hepatitis D, antibody-positive sera were submitted to rate zonal centrifugation to separate monomeric 7S from pentameric 19S immunoglobulin M antibodies. Sera were from 6 patients with acute self-limited hepatitis, 4 patients with chronic hepatitis D, and 6 patients with hepatitis D progressing to chronicity. The immunoglobulin M reactivity was measured by a specific immunoassay based on capture of mu-chains by anti-mu linked on a solid phase. Only 19S antibody was found in acute hepatitis D. In contrast, all patients with chronic hepatitis D circulated 7S antibody in addition to the 19S antibody. In patients with progressive hepatitis D, both the 7S and 19S antibody variants were present at the onset of the disease. The difference in the antibody response between acute hepatitis D and chronic hepatitis D is not only temporal and quantitative but also qualitative. The expression of 7S antibody seems to be an immunologic event specific for chronic hepatitis D.

Acute Disease↗
PubMed1989

Study of reactivation of chronic hepatitis delta infection.

Five patients with chronic hepatitis delta virus (HDV) infection suffered spontaneous episodes of liver enzyme elevation on a background of otherwise biochemically stable liver disease. In all five patients these episodes were accompanied by a rise in serum levels of anti-HDV IgM, HDV antigen and HDV RNA. These episodes of increased HDV replication accompanied by biochemical evidence of liver injury are reminiscent of reactivation in chronic hepatitis B. Surges of increased HDV replication may be important in the progression of liver disease in chronic HDV infection.

Adult↗
PubMed1989

Treatment of chronic hepatitis delta virus (HDV) infection with human lymphoblastoid alpha interferon.

Ten patients with evidence of continuing HDV replication were treated with lymphoblastoid alpha-interferon and eight more were followed as a non-randomized control group. Four out of eight patients who completed one year of follow-up had cleared HDV-RNA from the serum whilst none of the control group did so. In these four responding cases there was a transient increase in transaminase levels during treatment and in two, this was followed by improvement. One patient also cleared HBV and seroconverted to anti-HBs (antibody to hepatitis B surface antigen--HBsAg). In one patient with sustained loss of HDV, recurrence of HDV infection was detected 18 months after completion of treatment. These data suggest that alpha-interferon can inhibit HDV replication in the short term but relapse after one to two years may occur. Inhibition of HDV-RNA is associated with improvement in the inflammatory liver disease and now larger studies are required to determine whether it influences survival.

Adult↗
PubMed1987

Delta infection in eastern Sicily.

Sera from 619 HBsAg+ subjects living in eastern Sicily, consecutively collected from 1975-1985, were tested for markers of delta virus (HDV) infection: delta antigen (HDAg), antibodies to delta (anti-HDIg), and also for antibodies to HBcore of IgM type (anti-HBcIgM) and for the system HBe-anti-HBe. The subjects included 210 asymptomatic carriers, 238 patients with acute hepatitis and 171 patients with chronic liver disease. HDAg was not found in any of the samples. Anti-HD was found in 28/171 (16.3%) patients with chronic liver disease, in 13/210 (6%) asymptomatic HBsAg carriers and in 13/238 (5.4%) patients with acute hepatitis. None of our patients were drug addicts. One had a history of blood transfusion, and nine came from the same family unit. The prevalence of HDV infection in eastern Sicily is lower than in other areas of Sicily possibly because of the lower percentage of HBsAg carriers in the local population. Parenteral transmission of HDV does not seem to play a major role in our area, while the familial clustering suggests close body contact as an important way of spread.

Adolescent↗
PubMed1987

Inhibition of hepatitis delta virus (HDV) replication by lymphoblastoid human alpha interferon.

Lymphoblastoid interferon inhibited hepatitis delta virus (HDV) replication in four out of five HDV carriers with chronic active liver disease. Serum HDV-RNA was undetectable in three patients, but in one of these evidence of continuing intrahepatic HDV replication was present on biopsy one year after treatment. In the four cases which showed total or partial inhibition of HDV replication, there was a transient increase in transaminases during treatment, and in three this was followed by improvement. These effects lasted for longer than one year. The lysis of hepatocytes occurring on exposure to interferon may be related to the induction of 2-5A oligosynthetase which, in the presence of the dsRNA of HDV, activates endonucleases which destroy the rRNA of the infected cells.

Adult↗
PubMed1986

Cloned fragment of the hepatitis delta virus RNA genome: sequence and diagnostic application.

Hepatitis delta virus (HDV) is a replication-defective etiological agent of hepatitis that requires hepatitis B virus (HBV) as a helper. A complementary DNA (cDNA) fragment of the RNA genome of HDV was cloned into the plasmid vector pBR322, and the primary nucleotide sequence and predicted protein products of the cDNA fragment were determined. This cloned cDNA fragment has been used as a sensitive radioactive probe for the detection of HDV RNA in the serum of patients with either acute or chronic HDV infections.

Base Sequence↗