Search PubMed⌕ Search

Biomedical subjects

F Deinhardt

Publications and source records attributed to F Deinhardt.

At least 271 records · Page 15Linked to original sources
PubMed1978

Detection of HBeAg and anti-HBe in acute hepatitis B by a sensitive radioimmunoassay.

A solid-phase radioimmunoassay using anti-HBe-coated polysterence beads and iodine-125-labeled anti-HBe of human origin was developed for the detection of HBeAg. Anti-HBe could be determined by a blocking test. Both assays were about 500-fold more sensitive than immunodiffusion. Few nonspecific positive results for HBeAg could be recognized in the anti-HBe test by increase in cpm over that of the negative control. HBeAg was not found in acute hepatitis A and non A-non B hepatitis or in a control group of accident patients. On admission to the hospital 12 of 48 (25%) acute hepatitis B patients from Greece and 17 of 20 (85%) acute hepatitis B patients from Germany were HBeAg-positive. All 39 initially HBeAg negative sera were already anti-HBe positive. Tests of the acute stage and follow-up sera of the 20 German patients indicated that HBeAg is regularly present in the incubation period and early acute phase of hepatitis B. After onset of disease the antigen is cleared from the serum very rapidly in uncomplicated cases and is usually followed by the appearance of anti-HBe. Like anti-HBc, anti-HBe can serve as a tool for the diagnosis of hepatitis B after the disappearance of HBsAg.

Acute Disease↗
PubMed1978

Decrease in incidence of hepatitis A infections in Germany.

The hypothesis of a decline in the incidence of hepatitis A infections in Germany in recent decades was confirmed by determining the prevalence of hepatitis A antibody (anti-HAV) in sera collected in 1965 and in 1975 under the same conditions in North Germany. The prevalence of anti-HAV correlated with the year of birth and was independent of the time of serum sampling. The force of infection fell from 0.04 in 1945 to 0.005 in 1965 as judged from a catalytic epidemic model with a sigmoidal decrease.

Adolescent↗
PubMed1978

Spontaneous human mononuclear cell cytotoxicity to cultured tumor cells: reproducibility of serial measurements with the use of a chromium-51-release microcytotoxicity assay.

Twenty-three healthy human adults with naturally occurring (spontaneous) mononuclear cell cytotoxicity (MCC) to cultured human tumor cells were evaluated in a serial study over 23 months to determine whether their initial MCC levels remained stable. A 3-hour 51Cr-release microcytotoxicity assay, in which the HBT-3 cancer-derived cell line with HeLa markers and the ALAB breast cancer-derived cell line were used, was standardized and its suitability for such serial studies was evaluated. The data showed that the 51Cr-release assay is reproducible and suitable for use in serial studies of MCC. The intrinsic technical error for a single assay averaged 12.5% (2-26%) coefficient of variation. The greatest sources of technical variation with time were the passage level of the target cells and the temperature at which the effector cells were stored and handled. When these technical factors were controlled, naturally occurring MCC was fairly reproducible with time. Of the healthy individuals with initial high or low MCC levels, 61% tended to retain these levels in a stable fashion, but the remaining 39% studied showed fluctuations of MCC greater than 33% coefficient of variation.

Blood Preservation↗
PubMed1978

Oncogenicity of the C-type virus HL-23V in marmosets and characterization of virus isolated from an HL-23V-induced marmoset tumor: comparison with simian sarcoma virus type 1.

Dog thymus cells chronically infected with HL-23V, a C-type virus isolated from human acute myelogenous leukemia cells, produced both transforming and nontransforming virus indistinguishable from simian sarcoma virus type 1 (SSV-1/SSAV-1) and induced fibromas in newborn marmosets. All inoculated marmosets developed anti-HL-23V antibodies. A cell line established from a tumor biopsy produced transforming virus identical to SSV-1 and HL-23V at early passages. However, at later passages the cell line and a cell line established from residual tumor tissue removed at autopsy, produced virus which was neutralized only at low dilutions of anti-SSV-1 serum (1:32) relative to SSV-1 (1:1,024). This virus (BFV) was also distinguished from SSV-1 and HL-23V by XC tests, and by membrane immunofluorescence and serum cytotoxicity tests.

Animals↗
PubMed1978

Susceptibility of marmosets to Epstein-Barr virus-like baboon herpesviruses.

Epstein-Barr virus (EBV)-like herpeviruses, strains of Herpesvirus papio (HVP), have recently been isolated from lymphomatous (HVP-L) and from normal baboons (HVP-N). Both HVP isolates infect some species of marmosets, HVP-L inoculated adult animals develop a mild to severe and sometimes fatal lymphoproliferative disease whereas newborn marmosets of the same species do not develop a measureable disease after inoculation with HVP-l. HVP-N infects adult marmosets but does not cause disease.

Animals↗
PubMed1978

Overview of viral oncology studies in Saguinus and Callithrix species.

Marmoset monkeys are highly susceptible to tumor induction by type C sarcoma viruses and primate lymphotropic herpeviruses. Six experimental models were reviewed, three sarcoma models induced by Rous, feline or simian sarcoma viruses and three models of lymphoproliferative disease induced by Herpevirus saimiri, H. ateles or Epstein-Barr virus. Relative susceptibility of cotton-topped (Saguinus oedipus oedipus), white-lipped (S. nigricollis, S. fuscicollis subspecies) and commone (Callithrix jacchus jacchus) marmosets to the different viruses was compared.

Age Factors↗
PubMed1977

Transformation of lymphocytes by Herpesvirus papio.

Cotton-topped (CT) or white-lipped (WL) marmoset lymphocytes were transformed in vitro with herpesvirus papio (HVP) into permanently growing lymphoblastoid cell lines (LCL). Five of 9 HVP-transformed CT cell lines contained cells with antigens reacting with antibodies to Epstein-Barr virus (EBV) capsid antigen (VCA) and/or to EBV-induced early antigens (EA). None of 12 WL LCL revealed such antigen-producing cells. Cells from both groups of cultures failed to react with antibodies to the EBV-specified nuclear antigen (EBNA). Exposure of baboon circulating lymphocytes to X-irradiated HVP or EBV-carring cells, or to suspensions of EBV resulted in establishment of LCL which all contained VCA and/or EA-positive, but no EBNA-positive cells. Nuclear antigens were undetectable also with anti-VCA-positive sera from baboons, chimpanzees, or other non-human primates. DNA-complementary RNA (cRNA) filter hybridization with EBV cRNA showed that with one exception transformed CT or WL marmoset cells contained at least 1-2 virus genome equivalents per cell, while at least 12-25 virus genome equivalents per cell were detected in transformed baboon cells. These data need confirmation by DNA-DNA reassociation kinetics.

Animals↗
PubMed1977

Establishment of simian sarcoma virus, type 1 (SSV-1)-transformed non-producer marmoset cell lines.

Simian sarcoma virus, type 1 (SSV-1)-transformed non-producer cell lines were established by infection of normal marmoset fibroblast cells (HF) with limiting dilutions of SSV-1. Four focus-derived cell lines were identified as non-producers by assay of culture fluids for focus-forming activity and by the mixed culture cytopathogenicity test with XC cells. Further studies failed to detect production of type-C virus by 3H-uridine labelling, reverse transcriptase assay or electron microscopy. The non-producer cell lines, designated HF/SSV-NPI, IV, V, and VI, appeared morphologically transformed and cloned in soft agar with the same efficiency as HF/SSV-1 virus-producing transformed cells. Expression of either cytoplasmic or cell surface virus-related antigens was not detected by immunofluorescence or serum cytotoxicity tests. The presence of sarcoma genome in the transformed non-producer cell lines was demonstrated by rescue of focus-forming activity following superinfection with non-transforming helper virus or by cocultivation with helper-virus-producing cell lines. The SSV-1-transformed non-producer primate cells provide a useful tool for future studies.

Animals↗
PubMed1977

[Hepatitis B: new aspects, practical implications. Virology and epidemiology].

Although neither A nor B hepatitis virus (HAV, HBV) has been grown in cell or organ cultures, both agents have been identified and characterized. The subsequent ability to diagnose hepatitis A and B has led to the recognition of a third form of viral hepatitis, "non A--non B hepatitis". It has been possible to eliminate HBV from blood used for transfusion and from blood products, and the combined results of hepatitis research have led to a better understanding of the epidemiology and pathogenesis of viral hepatitis. The most important development, though, has been production of a vaccine with the prospect of controlling at least hepatitis B in the near future by active immunization. However, immunization experiments in man should proceed with the utmost caution and one must not underestimate the difficulties which still have to be overcome before vaccination against hepatitis B becomes routine.

Hepatitis B↗