Sixty-three intravenous drug addicts with HBsAg positive hepatitis were studied to evaluate the diagnostic usefulness of hepatitis delta virus (HDV) markers for diagnosis of acute HDV infection. Patients were tested for HBsAg, anti-HBc-IgM, and anti-HD-IgM by radioimmunoassay (RIA), and for hepatitis delta antigen (HD-Ag) by a commercial enzyme-linked immunoassay (ELISA). At least two serum samples at a mean interval of 4 wk were examined from each patient. HDV markers were found in 41 cases. In the first serum sample (obtained within 1-5 wk after onset of illness) HD-Ag was found in 32 cases and was the only HDV marker in 22; in the remaining 10 cases, HD-Ag was found along with total anti-HD, and in 6 of them anti-HD-IgM was also detected. Five additional patients were only positive for total anti-HD, and anti-HD of the IgM class was the only marker in one patient. HD-Ag was found more often in the patients studied during the first 2 wk of illness. In the second serum sample, HD-Ag was never the only marker detected, seven patients were still positive, and in all of them anti-HD was also present. Thirty patients were only positive for anti-HD. Seroconversion from HD-Ag to anti-HD occurred in 20 of 22 (91%) patients. The results suggest that HD-Ag determination by ELISA in the initial serum sample, during the first 2 wk of illness, may be the most sensitive test for the diagnosis of acute delta infection, and that seroconversion to anti-HD usually occurs after the sixth week of illness.

Acute Disease↗

PubMed1986

Immunoprophylaxis of perinatal transmission of the hepatitis B virus: efficacy of hepatitis B immune globulin and hepatitis B vaccine in a low-prevalence area.

One hundred eleven newborn infants born of Spanish hepatitis B surface antigen (HBsAg) carrier mothers were consecutively assigned to one of three treatment groups. Group A was treated with three or four doses of hepatitis B immune globulin (HBIG) in one of three different schedules. Group B received one dose of hepatitis B vaccine (Hevac-B, Pasteur) at birth and at 1, 2 and 12 months. Group C was treated with the same vaccination schedule as group B and in addition received a single dose of HBIG at birth. Comparisons were made in the 85 babies who had strictly completed the immunization schedule and had been followed for at least 12 months. The three immunization protocols were equally effective, since none of the children became a chronic HBsAg carrier or developed acute symptomatic infection. There were five transient and subclinical infections among children who received only HBIG (group A), one transient infection in group B, and one in group C. There seems to be some correlation between anti-HBs levels and degree of protection, since all transient infections in group A occurred in the subgroups who did not maintain protective antibodies during the first 6 months. Although the percentage of responders in the two vaccinated groups did not differ significantly, children who received only vaccine reached higher antibody levels than those who also received HBIG. Our results suggest that any immunization schedule able to maintain anti-HBs levels during the first 6 months of life would be useful to prevent mother-to-infant transmission of the hepatitis B virus in areas where most of the carrier women are expected to be anti-HBe positive and hence relatively less infectious.

Carrier State↗

PubMed1986

Overview of double-stranded RNA replication in Saccharomyces cerevisiae.

There are five families of double-stranded RNA (dsRNA) in strains of Saccharomyces cerevisiae, called L-A, L-BC, M, T, and W. Of these, L-A, L-BC, and M are found in intracellular virus-like particles (VLPs). Their replication is controlled by over 40 chromosomal genes; some (called MAK genes) promote dsRNA replication or maintenance, others (called SKI genes) negatively control dsRNA replication. Extensive genetic interactions among the dsRNAs and the chromosomal genes are known. The VLPs containing dsRNA produce a message (+) strand RNA copy in vitro, while the VLPs containing a (+) strand synthesize a (-) strand copy to make dsRNA. The genes MAK10 and PET18 (= MAK31 + MAK32) are necessary for the structural stability of L-A dsRNA-containing particles, but not of those containing L-A (+) strand RNA. The M1 VLPs can have either one or two M1 dsRNA molecules per particle, a fact that we explain by a sort of "head-full" hypothesis. [D] (for disease) is a new cytoplasmic genetic element which, when introduced into a ski M1 strain, makes the strain unable to grow at 20 degrees C or at 37 degrees C. [D] is not located on L-A, L-BC, M, or W dsRNA. Element [D] is heat-curable, and chromosomal mutants unable to maintain [D] (mad-) have been isolated. They can maintain M1 and L-A. [B] is a cytoplasmic genetic element which suppresses the usual need of M1 for MAK11 and several other MAK genes. Element [B] is not located on L-A or M and is distinct from [D].

Chromosomes↗

PubMed1986

In vitro L-A double-stranded RNA synthesis in virus-like particles from Saccharomyces cerevisiae.

Most strains of Saccharomyces cerevisiae harbor L-A double-stranded RNA (dsRNA), 4.5 kilobases long, contained in virus-like particles (VLPs). These L-A VLPs can be separated by CsCl density gradient centrifugation into a main peak of particles, containing full-length L-A dsRNA, which synthesizes only plus-strand single-stranded RNA (ssRNA), and a lighter fraction of VLPs, containing plus-strand ssRNA, which has L-A dsRNA-synthesizing activity. This dsRNA-synthesizing activity was present in particles from logarithmically growing cells but not from stationary-phase cells. The newly synthesized strand of dsRNA in the lightest particles was full-length minus strand. All or almost all of the new minus strand was synthesized in vitro, and the rate of chain elongation was approximately 100 nucleotides per minute. The lightest particles synthesized plus-strand ssRNA only after completion of dsRNA synthesis, indicating that the same particle contains dsRNA- and ssRNA-synthesizing enzyme(s). We also observed dsRNA-synthesizing activity in L-BC dsRNA-containing particles similar to that in L-A VLPs.

Genes, Fungal↗

PubMed1986

Prolonged inhibition of hepatitis B virus replication with vidarabine monophosphate in chronic active type B hepatitis.

Eight patients with chronic (mean 52 months) type B hepatitis (chronic active hepatitis and active cirrhosis) and markers of active viral replication (presence of HBeAg and HBV-DNA in serum) were treated with Ara-AMP for 7-12 weeks. The mean follow-up time was 18.3 months. All but one patient responded to treatment. In seven patients, HBeAg and HBV-DNA became negative and developed anti-HBe. One patient lost HBsAg as well as HBeAg and HBV-DNA. HBcAg in liver tissue became undetectable or greatly reduced in the seven patients in whom it was strongly positive. Aminotransferase and immunoglobulin levels reverted to normal in the seven responders and remained normal through the entire follow-up period. A second liver biopsy, performed after completion of therapy, showed improvement in six of eight cases, with disappearance of lobular activity. Two patients treated for 12 weeks developed a severe polyneuropathy lasting for 6 months. A 7-week course of Ara-AMP seems to induce long-lasting inhibition of viral replication, along with an improvement in liver function tests and liver histology, without significant side effects. On the other hand, a 12-week course was associated with the development of a severe and prolonged polyneuropathy.

Adult↗

PubMed1986

Three different M1 RNA-containing viruslike particle types in Saccharomyces cerevisiae: in vitro M1 double-stranded RNA synthesis.

Killer strains of Saccharomyces cerevisiae bear at least two different double-stranded RNAs (dsRNAs) encapsidated in 39-nm viruslike particles (VLPs) of which the major coat protein is coded by the larger RNA (L-A dsRNA). The smaller dsRNA (M1 or M2) encodes an extracellular protein toxin (K1 or K2 toxin). Based on their densities on CsCl gradients, L-A- and M1-containing particles can be separated. Using this method, we detected a new type of M1 dsRNA-containing VLP (M1-H VLP, for heavy) that has a higher density than those previously reported (M1-L VLP, for light). M1-H and M1-L VLPs are present together in the same strains and in all those we tested. M1-H, M1-L, and L-A VLPs all have the same types of proteins in the same approximate proportions, but whereas L-A VLPs and M1-L VLPs have one dsRNA molecule per particle, M1-H VLPs contain two M1 dsRNA molecules per particle. Their RNA polymerase produces mainly plus single strands that are all extruded in the case of M1-H particles but are partially retained inside the M1-L particles to be used later for dsRNA synthesis. We show that M1-H VLPs are formed in vitro from the M1-L VLPs. We also show that the peak of M1 dsRNA synthesis is in fractions lighter than M1-L VLPs, presumably those carrying only a single plus M1 strand. We suggest that VLPs carrying two M1 dsRNAs (each 1.8 kilobases) can exist because the particle is designed to carry one L-A dsRNA (4.5 kilobases).

DNA↗

PubMed1986

[Prevalence of markers of infection with hepatitis B, delta and HTLV-III viruses in the mentally retarded].

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗

PubMed1986

Diagnostic usefulness of anti-HBc-IgM and anti-HD antibodies in acute viral hepatitis.

To evaluate diagnostic improvement achieved with the determination of antibody to hepatitis core antigen of IgM type (anti-HBc-IgM) and antibody to delta antigen (anti-HD) in acute type B hepatitis, 155 patients (of whom 100 were drug addicts) were studied, using these markers in association with the classical markers of viral hepatitis (anti-HBc, anti-HBs, anti-HAV-IgM and anti-cytomegalovirus antibodies). With classical diagnostic criteria, 121 patients would have been diagnosed as having B hepatitis (HBs Ag and/or anti-HBc antibody positive without anti-HBs antibody), 33 non A non-B hepatitis (all markers negative or anti-HBc and anti-HBs positive) and 3 A hepatitis (anti-HAV-IgM antibody positive). With the current markers, 89 were B hepatitis (anti-HBc-IgM antibody positive), 18 were simultaneous B and D infections (anti-HBc-IgM and anti-HD antibodies positive), 6 were D hepatitis (anti-HBc-IgM antibody negative and anti-HD antibody positive), 39 non-A non-B hepatitis (anti-HBc-IgM, anti-HD, HAV-IgM and anti-cytomegalovirus antibodies negative) and 3 hepatitis A. Of the 121 cases initially diagnosed as B hepatitis, only 79 were actually B hepatitis, 16 were simultaneous B and D infections, 6 D hepatitis, 18 non-A non-B hepatitis and 2 A hepatitis. Of the 33 cases considered to be non A non-B hepatitis, only 21 were really non-A non-B hepatitis; 10 were B hepatitis and 2 B and D hepatitis. When anti-HBc-IgM and anti-HD antibodies were determined, the initial diagnosis was modified in 54 of 155 cases (35 p. 100).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1985