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H Norder

Publications and source records attributed to H Norder.

46 records · Page 3Linked to original sources
PubMed1990

Typing of hepatitis B virus genomes by a simplified polymerase chain reaction.

The amplification of hepatitis B virus (HBV) DNA sequences in sera for molecular epidemiology of HBV is an important application of the polymerase chain reaction (PCR) with regard to HBV. To simplify the PCR for this purpose, the optimal concentrations of SDS and detergents for carrying out the proteinase K digestion and the amplification of DNA by Taq polymerase were evaluated. It was found that by using 1% deoxycholic acid as detergent for the proteinase K step and diluting the digest 10 times before carrying out the PCR, the phenol extraction of DNA became superfluous. The sensitivity of this procedure equalled that of PCR after phenol extraction on comparable amounts of serum. Four pairs of oligonucleotide primers were compared for amplification of HBV DNA sequences in 48 sera previously subtyped with respect to hepatitis B surface antigen (HBsAg), and in eight sera with different genotypes of HBV, representing the subtypes of HBsAg P1 to P8, defined at an international meeting [Couroucé-Pauty et al.: "HBs Antigen Subtypes." Basel: Karger, 1976]. Two primer pairs, selected from conserved regions in the X and S genes of HBV, gave a positive PCR with sera harbouring all the eight different strains of HBV, resulting in DNA fragments consistent with the sizes deduced from genome sequence data. Two other primer pairs were selected in order to discriminate genotypes with regard to differences between d/y and w/r strains.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1989

High frequency of hepatitis B virus DNA in anti-HBe positive sera on longitudinal follow-up of patients with renal transplants and chronic hepatitis B.

Hepatitis B virus (HBV) markers were determined in 821 patients receiving renal allografts and undergoing immunosuppressive therapy during 1970-1986. Twenty-four of the patients with a renal transplant functioning for longer than 1 year originally were or became chronic carriers of hepatitis B surface antigen (HBsAg). These patients remained carriers during the follow-up period, which lasted until death or until the end of 1986. Follow-up time was 1.2-15.3 years (mean 9.1 years). A total of 301 samples from the HBsAg-positive patients were tested for HBV DNA and HBeAg/DNA and HBeAg/anti-HBe. Nine patients who were constantly positive for HBeAg also remained positive for HBV DNA. Reactivation of HBV replication occurred in 11 patients. Among these, HBV DNA and HBeAg varied in parallel in six patients, three patients developed anti-HBe, and two patients were constantly positive for anti-HBe. Another four of the 24 patients seroconverted to anti-HBe, and two of these also lost HBV DNA. Three of 12 deceased patients died from liver failure during follow-up. None of these three had been constantly positive for HBeAg or HBV DNA, but they had had reactivations of HBV; two were also positive for HBV DNA in serum specimens available from their terminal month. HBV DNA was demonstrated in 99% of HBeAg-positive and 53% of anti-HBe-positive sera and in at least two samples from each of the 24 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Immunoglobulin isotypes of anti-HBc and anti-HBe and hepatitis B virus (HBV) DNA elimination in acute hepatitis B.

Antibodies to hepatitis B core antigen (anti-HBc) and e antigen (anti-HBe) were assayed in 46 sera from ten patients with acute hepatitis B utilizing immunoglobulin class- and subclass-specific enzyme immunoassays (EIAs). The sera were sampled 1 to 512 days after onset of hepatic symptoms. Four patients cleared HBsAg rapidly, within 24 days, and six patients cleared HBsAg slowly, within 27-74 days after the onset of symptoms. In three of the patients with rapid clearance of HBsAg, hepatitis B virus (HBV) DNA was not detected in sera tested during the first week after onset. The fourth patient was not tested until 12 days after onset and was then found to be negative for HBV DNA. In four of the patients with slow clearance of HBsAg, HBV DNA was present during the first week of illness. In the other two patients, HBV DNA was not detected in the first serum, 11 and 17 days after the onset of illness. Anti-HBc IgM and IgA1 were detected in all patients, with maximum titers shortly after onset. Anti-HBc IgG1 was present in all sera tested. Anti-HBc IgG2 was not detected in any of the sera. Anti-HBc IgG3 and IgG4 were detected in all patient sera, with IgG3 paralleling IgG1, and IgG4 mainly in sera long after onset. Anti-HBe IgG1, IgG3, and IgG4 were detected in three, two, and two patients, respectively. Anti-HBe IgG2, IgM, IgA1, or IgA2 was not found in any patient. The time required for maximum titer of anti-HBc IgG1 was shorter in the patients with rapid clearance of HBsAg.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

A solid-phase reverse immunosorbent test for the detection of enterovirus IgM.

IgM antibodies against enterovirus antigen were determined by solid-phase reverse immunosorbent test (SPRIST). The 145 sera studied were sampled from cases of enterovirus infections diagnosed by virus isolation and/or complement fixation. In 91 sera from enterovirus infections diagnosed by virus isolation 11/40, 16/28 and 9/23 were positive in SPRIST against ECHO 3 and/or Coxsackie B3 antigen during the first, during the second and third, and after 3 weeks of illness, respectively. The corresponding figures for 85 sera from enterovirus infections diagnosed by a greater than or equal to 4-fold rise in complement fixing (CF) antibody titre against antigen from ECHO 18 and/or Coxsackie B5 antigen were 10/39, 12/20 and 9/26. None out of 22 sera with rheumatoid factor reacted in SPRIST, but 1/92 and 1/154 sera from blood donors was positive in SPRIST with Coxsackie B3 and ECHO 3 antigen, respectively. IgM antibodies against ECHO 3 antigen as determined by SPRIST were found to be cross-reactive over a broad range of enterovirus types and positive results were recorded with sera from infections with Coxsackie A9, B3, B4, B5, ECHO 3, 9, 17, 18, 25 and 30. Heterotypic titres in SPRIST were of the same magnitude (up to 25,600) as recorded against the homotypic virus, 12,800 and 1,600, in two sera from one patient with an ECHO 3 infection. SPRIST was found to be a rapid convenient, cross-reactive and a cheap mu-capture assay for enteroviruses with more than 50% sensitivity during the second and third weeks after onset of illness.

Coxsackievirus Infections↗
PubMed1987

Epidemiology of hepatitis B in Somalia: inference from a cross-sectional survey of serological markers.

Hepatitis B markers were determined by radioimmunoassay in 383 adults from different areas of Somalia and in 135 pregnant females and 428 children from Mogadishu. The highest incidence of HBsAg among adults was among nomadic males (20/85; 23%). The frequencies were lower in males from the agricultural and coastal area, i.e. 16/93 (17%) and 14/98 (14%) respectively. The lowest frequency of HBsAg was among women from the coastal area (6/72; 8%). Among the pregnant women 14 were positive for HBsAg, none of whom had HBeAg. Low levels of positivity for HBsAg were found both among children under 4 years and among those between 4 and 13 years of age - 3/94 (3%) and 5/128 (4%) respectively. In the age group 15-19 years, 50% showed seroconversion from HBeAg to anti-HBe. 7 out of 41 HBsAg carriers of ages over 20 had HBeAg. Early seroconversion from HBeAg to anti-HBe and a low level of HBsAg positivity in children indicate that vertical transmission is not important in Somalia. The low frequency of HBsAg in Mogadishu children may have one of the following explanations: (i) the infection occurs during adolescence, (ii) Mogadishu is a low-prevalence area and the examined adults were not born in Mogadishu, or (iii) a change in hepatitis B epidemiology has taken place in the area during the last 2 decades and the relatively higher prevalence of HBsAg in adults might reflect higher rates of infection in their childhood.

Adolescent↗
PubMed1984

Reactivity of sera from patients with liver disease with glutaraldehyde-treated erythrocytes: role for false positive results in hemagglutination tests.

The use of glutaraldehyde as a coupling reagent in the passive hemagglutination test (HA) has gained wide application, especially for the coating of red blood cells (RBC) with glutaraldehyde-polymerized human serum albumin (pHSA), for studies of the albumin receptor on hepatitis B surface antigen (HBsAg) or for the detection of anti-albumin antibodies (AAA). Here we report a previously unrecognized reactivity with glutaraldehyde-treated RBC mainly with sera from patients with liver disease. The highest incidences of this reaction were found in patients with acute viral hepatitis A and B, namely 44 of 50 (88%) and 31 of 50 (62%) respectively. In 234 HBsAg carriers the frequency was low (3%). This reactivity was also observed in 19 of 50 sera from patients with chronic liver disease documented by biopsy, but not in sera from 68 healthy subjects. By immunofluorescence on glutaraldehyde-treated RBC it was shown that the corresponding antibodies belonged mainly to the IgM class. In all HBsAg-negative patients studied the HA titer against glutaraldehyde-treated RBC was in agreement with the titer against RBC coated with pHSA or pBSA (polymerized bovine serum albumin). Absorption with pHSA abolished the reaction with glutaraldehyde-treated RBC in 7 of 8 sera, suggesting a common reactivity between glutaraldehyde-polymerized HSA and glutaraldehyde-treated RBC. Apart from the possible clinical importance of these antibodies, their existence is a possible source of false positive results when glutaraldehyde is used as a coupling reagent for immunological assays, in particular with sera from patients with liver diseases.

Actins↗
PubMed1981

Covalent chromatography as a means of isolating thiol peptides from large proteins: application to human ceruloplasmin.

The use of activated thiopropyl-Sepharose for simple and rapid isolation of thiol peptides from large proteins was investigated using ceruloplasmin (a copper protein of molecular weight 134,000 containing three cysteines and six disulphides) as a test case. Optimal results for the immobilization of the protein to the activated gel were obtained at pH 4.0 in the presence of 8 M urea and 0.05 M ethylenediaminetetraacetic acid. In these conditions 96% of the protein thiol groups were attached to the adsorbent. The immobilized protein was digested with either pepsin or trypsin. The liberated non-thiol peptides were eluted from the gel together with the protease after the digestion. After washing, the covalently attached thiol peptides were eluted in reducing buffer, desalted on the hydrophobic gel Sephadex LH-20 and carboxymethylated. The peptides were purified in a two-step procedure involving gel filtration on Sephadex G-25 and either column electrophoresis or ion-exchange chromatography. The two sets of peptides were derived from four different regions in the protein. They were 12-39 residues in length and together accounted for 152 residues. It is shown that the peptide chain was susceptible to proteolytic attack also close to the point of attachment (two residues away). One peptide with two thiol groups proved to be derived from an area containing one disulphide bridge in addition to cysteine. This bridge could be identified in a separate experiment where a second enzyme was used to release the disulphide peptide after the first digestion and washings.

Amino Acid Sequence↗
PubMedDate not supplied

Minor role of hepatitis B virus in the causation of chronic liver disease in Somalia indicated by a case-control study.

Chronic liver disease (CLD) is frequent in Somalia. In a case-control study, 116 in-patients with CLD were compared with the same number of age and sex matched controls. Demographic variables, use of drugs, symptoms and signs, serological markers for hepatitis B virus (HBV) and serum alpha-foetoprotein (AFP) were assessed. Hepatitis B surface antigen (HBsAg) was found in 44 cases of which 17 had antibodies to hepatitis D virus (anti-HD) and 7 had hepatitis B e antigen (HBeAg). Twenty-three controls were HBsAg-positive, of whom 3 had anti-HD and one HBeAg. Increased relative risks (95% confidence intervals in parentheses) were 2.5 (1.3-4.5) for HBsAg, 6.5 (1.7-21.5) for anti-HD, and 7.4 (0.9-66.5) for HBeAg. Despite the association between the presence of HBV markers and CLD, 62% of the cases had no markers indicating current HBV infection. This was reflected in the low risk attributable to chronic HBV infection (22.6%), which was lower than that in patients with CLD in other African populations with a high HBsAg carrier rate. The prevalence of HBV markers did not differ between cases with AFP greater than 100 ng/ml and those with AFP less than 100 ng/ml. The former were characterized by male predominance, shorter duration of symptoms, and larger mean liver size, indicative of malignancy. The mean age of HBsAg-positive cases with AFP greater than 100 ng/ml was significantly lower (by 7.7 years) than that of HBsAg-negative cases with AFP greater than 100 ng/ml. Among the CLD patients with AFP less than 100 ng/ml, 48 were HBsAg-negative. These cases differed significantly from the other 68 cases in that more were females (35% against 16%), more originated from an agricultural area (56% against 30%), and more were regular consumers of drugs (48% against 28%). In conclusion, factors as yet undefined play a considerable role in the causation of CLD in Somalia. The possibility of determining the role of hepatitis C virus (HCV) awaits the development of more specific assays for anti-HCV antibodies.

Adolescent↗