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K J Figenschau

Publications and source records attributed to K J Figenschau.

14 recordsLinked to original sources
PubMed1999

Identification of clinical isolates of Mycobacterium spp. by sequence analysis of the 16S ribosomal RNA gene. Experience from a clinical laboratory.

Twenty-one mycobacterial type strains and 334 clinical isolates of mycobacteria were identified by standardized sequence analysis using part of the gene encoding 16S rRNA. Apart from two clinical isolates, the resulting sequences corresponded to previously published sequences. The results of the molecular determinations of the type strains completely overlapped the identities obtained using conventional techniques (cultural characteristics, biochemical tests, commercial DNA probes, and gas chromatographic lipid profiles). Of 323 isolates conventionally identified as slow-growing mycobacteria, 318 (98.5%) were identified to the same species or group level by 16S rDNA sequence analysis, while 6 of the 11 strains of rapid growers obtained a corresponding identity with the two approaches. The sequencing protocol combined with a few cultural characteristics (i.e. growth rate, pigmentation and susceptibility testing) offers a rapid, reliable and usually definite identification of mycobacterial isolates.

Amino Acid Sequence↗
PubMed1994

[New cases of HIV infection. Estimation of the time of transmission].

During 1991 and 1992, 107 HIV infections were diagnosed at Ullevål hospital, Oslo. Previously collected serum specimens from 53 of these persons were tested with different anti-HIV and HIV antigen tests. Some of the sera were also examined for HIV RNA using PCR. Based on these results, the intervals between the last HIV negative and the first positive samples, and between the first HIV positive sample and the HIV diagnosis, were calculated. 38 persons had delivered HIV negative samples before their first positive sample. In addition, eight persons had a sample with serological markers of recent infection. For these 46 persons, the median time between the last HIV negative sample and the diagnosis was one year. 36 of them were HIV negative three years before diagnosis. For 19 persons, markers of HIV infection were detected in samples taken before the disease was first diagnosed. For two persons HIV markers were present in samples taken as early as 1986.

AIDS Serodiagnosis↗
PubMed1993

Hepatitis C virus (HCV) RNA among anti-HCV-positive blood donors and their recipients.

Seven of 24 blood donors positive in Ortho's first-generation antibody to hepatitis C virus (anti-HCV) test (EIA-1) were also positive in Ortho's second-generation test (EIA-2). All 7 had at least two anti-HCV positive recipients, whereas only 1 of the 17 EIA-2-negative donors had an anti-HCV-positive recipient. This recipient was a multitransfused patient with von Willebrand's disease. Five of the 7 EIA-2-positive donors had detectable HCV RNA. We traced and tested 38 of the still living blood recipients from the 7 EIA-2-positive donors. Twenty-eight of these were EIA-2 positive and 22 were HCV-PCR positive. One patient with Waldenstroem's hypergammaglobulinemia was EIA-2 negative but HCV-PCR positive. All the EIA-2-positive sera showed reactivity in Ortho's recombinant immunoblot assay (RIBA-2), but 5 of the 28 recipients and 1 of the donors reacted with only one band (RIBA-2 indeterminate). Among 32 recipients who probably had received EIA-2-positive blood, 29 (91%) had markers of an HCV infection. Twenty-two (75%) of the HCV-infected recipients had detectable HCV RNA more than 6 months after transfusion and hence were chronic HCV carriers.

Base Sequence↗
PubMed1992

Magnetic bead antigen capture enzyme-linked immunoassay in microtitre trays for rapid detection of schistosomal circulating anodic antigen.

We have developed a new magnetic bead antigen capture enzyme-linked immunoassay for the detection of schistosomal circulating anodic antigen. The assay utilizes IgG1 monoclonal antibody coated monodisperse magnetic beads in microtitre trays fitted to a special magnet. The total test time was found to be 1-2 h, using 0.05 mg beads per well. The lower detection level was 0.7 ng AWA-TCA per ml (approximately 0.07 ng CAA per ml). Validation by sera from uninfected and Schistosoma mansoni infected Africans and Norwegians resulted in an assay specificity of 100% and sensitivity was close to 90% for cases excreting more than 100 eggs per gram faeces. At such clinically relevant levels the inter-assay CV was below 10% and photometric absorbance correlated to antigen levels was nearly linear. There was a significant correlation between the magnetic bead EIA absorbance values and the titres obtained using the previously established ELISA. The new bead assay, however, was easier and less laborious because TCA pretreatment and the titration of positive results were unnecessary.

Africa↗
PubMed1990

Detection of serum antibodies against Borrelia burgdorferi with some commercially available serological tests.

Sixty-three sera were analysed for antibodies against Borrelia burgdorferi with an in-house indirect immunofluorescence assay. Thirty-nine sera were positive (titer greater than or equal to 256), seven borderline (titer 128) and 17 negative (titer less than or equal to 64). These results were compared with results obtained with four different commercial assays for detection of such antibodies. Indirect immunofluorescence tests yielded most positive results. The flagellin ELISA test detected antibodies in patients with erythema chronicum migrans (ECM) more often than the other test systems. Sera from patients with acrodermatitis chronica atrophicans (ACA) were positive in all systems. The serological diagnosis of borreliosis is difficult and direct methods for detecting the presence of the microbe are highly needed.

Antibodies, Bacterial↗
PubMed1988

Invasiveness of enterobacteria related to the presence of high molecular weight plasmids.

A study of 41 strains of Shigella, Escherichia coli, and Salmonella was performed. The presence of high-molecular-weight plasmids, invasiveness in HEp-2 cells and the ability to produce a positive Serény test were tested. Five of the seven strains of Salmonella typhimurium harboured a 62 Md plasmid and invaded HEp-2 cells. Two strains of S. typhimurium and a S. paratyphi-B strain lacked plasmids but were still invasive. Among the 27 strains of Shigella and enteroinvasive E. coli (EIEC) 25 strains harboured a high molecular weight plasmid. 27 of the Shigella/EIEC strains invaded HEp-2 cells and 25 produced a positive Serény test. One strain of Shigella sonnei was invasive in HEp-2 cells and gave a positive Serény test, but plasmids were not demonstrated. Of the eight non-enteropathogenic E. coli 5 strains harboured plasmids of 100 to 140 Md size; only one of the strains invaded HEp-2 cells; none of the strains produced a positive Serény test. The study shows that tests for pathogenicity (Serény test, HEp-2 cell test) are usually positive in the Shigella and EIEC group of bacteria; these bacteria also usually carry a high molecular weight plasmid. However, among non-enteropathogenic bacteria plasmids of 100 to 140 Md size can be observed without any correlation to invasive properties. Genetic information from gene loci located to plasmids and chromosomes is required to give a positive Serény test. The presence of high molecular weight plasmids does not seem to be necessary for expression of in vitro invasiveness of S. typhimurium.

Animals↗
PubMed1983

A rotavirus staphylococcal co-agglutination test.

A simple and rapid staphylococcal co-agglutination (SA) test for detection of rotavirus in human faecal specimens is described. A suspension of protein A-containing staphylococci coated with a rabbit hyperimmune serum against the rotavirus strain of calf diarrhoeae virus was used as reagent. Before the SA test, the faecal specimens were absorbed with a suspension of uncoated staphylococci. 34 of 36 rotavirus immune electron microscopy (IEM) positive samples showed a positive SA test, whereas none of 41 IEM negative specimens agglutinated the staphylococcal reagent. The SA test was as sensitive as an enzyme-linked immunosorbent assay (Rotazyme) and in our hands more sensitive than a latex agglutination test (Rotalex).

Antibodies, Viral↗
PubMed1976

A reovirus-like agent (rotavirus) in gastroenteritis of children. Virus detection and serological studies.

A reovirus-like agent (rotavirus) was detected in 26 children (44%) when fecal specimens from 59 children with acute gastroenteritis were examined by electron microscopy. No rotavirus was detected in the feces of 49 children with other diseases. Sera from the acute and the convalescent phase from 40 children with acute gastroenteritis and from 18 other patients were examined for antibodies against a bovine rotavirus by an indirect fluorescent antibody test. 26 of the patients with gastroenteritis (65%) developed antibodies during their disease, whereas none of the other patients showed a rise in antibody titre. The specimens were submitted to the laboratory from hospitalized children during the period January 1973 through March 1975. Most of the cases of rotavirus gastroenteritis occurred during late autumn and early winter among children between 0.5 and 3 years of age. It is concluded that electron microscopy is a sensitive diagnostic technique during the acute phase of the disease, and that the serological test with bovine rotavirus antigen served as a useful diagnostic tool.

Acute Disease↗
PubMedDate not supplied

Quantitative detection of schistosomal circulating anodic antigen by a magnetic bead antigen capture enzyme-linked immunosorbent assay (MBAC-EIA) before and after mass chemotherapy.

The magnetic bead antigen capture enzyme-linked immunosorbent assay (MBAC-EIA) has been applied to detect schistosomal circulating anodic antigen (CAA) in pre- and post-treatment sera from 55 individuals in a Schistosoma mansoni control project in the Blue Nile valley of western Ethiopia. The amounts of CAA detected by this assay were positively correlated with the numbers of eggs per gram of faeces (epg). A significant reduction in CAA levels as measured by the MBAC-EIA was observed after mass chemotherapy. The sensitivity was 88-89% in clinically significant cases excreting more than 100 epg. In light infections, however, the sensitivity was lower. None of 32 uninfected Norwegian blood donors or 12 Ethiopian immigrants to Norway were positive. The specificity was thus estimated to be 100%. The test is rapid (1-2 h) and simple to perform without sophisticated equipment and could therefore, with slight modification, be used as a reliable method of diagnosis at field level in endemic areas undergoing mass chemotherapy campaigns or population surveys.

Animals↗