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T Gotlieb-Stematsky

Publications and source records attributed to T Gotlieb-Stematsky.

At least 19 recordsLinked to original sources
PubMed1992

Inhibition of the reverse transcriptase activity and replication of human immunodeficiency virus type 1 by AS 101 in vitro.

In a search for compounds active against human immunodeficiency virus type 1 (HIV-1), it was found that the novel low-molecular weight immunoenhancer ammonium trichloro(dioxyethylene-O,O'-) tellurate (AS101) suppresses production of HIV-1 in vitro. Treatment of HIV-1-infected peripheral blood mononuclear cells (PBMC) with increasing concentrations of AS101 resulted in substantial inhibition of virus production as measured by both reverse transcriptase (RT) activity and antigen presence in supernatants of treated cells. AS101 had no effect on PBMC viability, growth, or morphology up to a concentration of 15 microM for 14 days. To elucidate a possible mechanism for the inhibition of AS101, we have analyzed the effect of the drug on the catalytic functions associated with HIV RT, namely the RDDP, DDDP, and RNase H activities. RDDP and DDDP activities were impaired by the drug with calculated IC50 value of about 4 microM. On the other hand, the RNase H activity was less sensitive to AS101, with an apparent IC50 value of about 30 microM. The anti-HIV-1 activity of AS101 as reflected by inhibition of the different catalytic functions associated with viral RT, in the absence of drug-related toxicity to lymphocytes, together with its immunomodulating activity strongly argues in favor of its evaluation, as a therapeutic agent for patients with HIV infection.

Antiviral Agents↗
PubMed1992

Uniformity of serotype and electropherotype in local human rotavirus isolates during each of three successive cold seasons.

Each of three consecutive cold seasons (November-March) in the town of Tiberias, Israel, was dominated by one particular rotavirus serotype causing acute diarrhoea in the community: the 1987/88 season by serotype-2; 1988/89 by serotype-1 and 1989/90 by serotype-4. Each season was also characterized by a particular pattern of rotaviral RNA when visualized using electrophoresis in gels. RNA profiles of identical rota serotypes and serotypic prevalence for any given cold season were unique for the town of Tiberias and different from other localities throughout Israel. The meaning of these findings in terms of herd immunity is discussed.

Acute Disease↗
PubMed1991

EBV genome and immunoglobulin gene rearrangement in the differential diagnosis of nasopharyngeal carcinoma and lymphoma.

Head and neck tumors include nasopharyngeal carcinoma (NPC) and lymphoma. The differential diagnosis of these tumors is based on histology, immunocytochemical staining, and EBV serology. In rare cases it might be difficult to distinguish between NPC and lymphoma in HE section or biopsies. DNA hybridization with cloned EBV and human immunoglobulin gene fragments allows the detection of EBV-related sequences and immunoglobulin gene rearrangements. The presence of EBV genome supports the diagnosis of NPC or EBV related BL, while rearrangement of immunoglobulin genes points to B-cell lymphoma. The diagnosis in 11 patients suspected of head and neck tumors was carried out by hybridization of DNA extracted from the tumors and assayed with cloned EBV and IgHCJ DNA probes. One patient proved to have EBV-associated BL based on positive hybridization with EBV probes and immunoglobulin rearrangement, presenting a unique hybridization with cloned EBV DNA BamHI W fragment, with bands of 3.2 and 3.9 kb. BL was confirmed in this patient by demonstration of c-myc rearrangement. A second patient was negative in hybridization with EBV, and positive for immunoglobulin rearrangement, and therefore was diagnosed as having B-cell lymphoma. In seven patients NPC was confirmed by hybridization with EBV-DNA probes. In two patients, both NPC and B-cell lymphomas were excluded.

Adolescent↗
PubMed1990

Molecular identification by RNA-RNA hybridization of a human rotavirus that is closely related to rotaviruses of feline and canine origin.

With a few exceptions subgroup I group A human rotavirus strains have short RNA patterns, whereas most animal rotavirus strains belong to subgroup I and have long RNA patterns. Thus, new isolates of subgroup I human rotaviruses with long RNA patterns are considered to have a high likelihood of being animal rotaviruses. A group of human rotaviruses represented by the AU-1 strain has recently been shown to be genetically related to a feline rotavirus (FRV-1) isolated in Japan. A human rotavirus, strain Ro1845, which is similar to the AU-1 strain in its subgroup (I), serotype (3), and electropherotype (long), was compared with various human and animal strains by RNA-RNA hybridization to determine its genogroup, a term proposed to classify rotaviruses based on their gene homology. The Ro1845 strain did not show a significant level of homology with AU-1, FRV-1, or other human strains, indicating that the Ro1845 strain is different in its genogroup not only from the AU-1 strain but also from other human strains. However, the Ro1845 strain showed a high degree of homology with another feline rotavirus (Cat97) isolated previously in Australia, suggesting that the Ro1845 strain might originate from a feline rotavirus that is genetically distinct from the Japanese FRV-1 strain. Furthermore, the Ro1845 strain as well as the Cat97 strain were related genetically to the canine rotavirus RS15 strain. Taken together, these results indicate that at least two genogroups are present in feline rotaviruses, one resembling the AU-1 strain and the other resembling the Ro1845 strain as well as canine rotaviruses.

Animals↗
PubMed1990

Serum interferon in first psychotic attack.

A group of 34 physically healthy young patients, aged 18-27 years at their first psychotic attack, before neuroleptic treatment and admission, were tested simultaneously with 24 age- and sex-matched controls for levels of serum interferon. No statistically significant differences were found between patients and controls. Therefore, no correlation between acute viral infection and schizophrenia was demonstrated.

Adolescent↗
PubMed1990

Absence of T cell impairments in a unique group of anal-receptive transvestite and male prostitutes in Israel.

High rates of immunologic abnormalities in asymptomatic, clinically healthy urban homosexual men have been associated with promiscuous, unprotected receptive rectal intercourse, and related to infection by the human immunodeficiency virus (HIV), Epstein-Barr virus (EBV) and cytomegalovirus (CMV). In cohort studies in Israel, which is still a low risk country for HIV infection and AIDS, about 40% of asymptomatic, clinically healthy male homosexuals consistently showed T cell defects that were not correlated with anal-receptive sexual behavior and were independent of HIV antibody status. Since pre-existing immune impairments in HIV-seronegative individuals have been implicated as a risk factor for seroconversion, we have attempted to investigate more precisely the role of anal-receptive homosexual activity as a risk factor for the acquisition of immune defects. We compared T lymphocyte profiles and mean geometric titers of EBV and CMV in a homogeneous group of 14 transvestite and male anal-receptive homosexual prostitutes with those of 77 HIV-seronegative male homosexuals who were not exclusively anally passive with multiple sex partners. While 44% of the control group showed a decrease of total T cells or their subpopulations as compared with normal heterosexual men (P less than 0.001), T lymphocyte values of the anal-receptive prostitutes were within the normal range. In the prostitutes, serum antibodies to HIV were detected in only 1 individual, to CMV in 12 of 13, and to EBV in all. Despite high mean geometric titers of antibodies to CMV (86.6) and EBV (25.8), frequent anal-receptive intercourse was not sufficient, in itself, to cause immune impairment in this unique group. The results suggest that the problem of cofactors contributing to immune deficiency in male homosexuals should be reexamined in countries with a low incidence for HIV seropositivity and AIDS.

Adolescent↗
PubMed1989

[Detection of antigen and antibody in herpes simplex encephalitis].

Laboratory confirmation of herpes simplex (HSV) infection in patients suspected of HSV encephalitis (HSV-E) at the earliest stage of the disease, may contribute greatly to the differential diagnosis and to the initiation of effective antiviral treatment. Our diagnosis of HSV infection was based on: a) detection of viral antigen in CSF cells in the first week of disease by immunofluorescence assay employing monoclonal antibodies against HSV-1 or HSV-2; b) detection of local IgM- and IgG-specific antibodies to HSV in the CSF and in the serum; c) ratio of titers of HSV antibodies in CSF and in serum less than 1:20; d) 4-fold rise in antibody titer to HSV in CSF and/or serum. The incidence of HSV-E was examined through 1987 in 270 patients suspected of viral infection of the central nervous system. In 187 (69.5%) material for laboratory diagnosis was inadequate and in 75 (27.8%) no evidence for infection by HSV was found. HSV infection was confirmed in 8 (2.9%), comprising 9.6% of those with adequate material for laboratory diagnosis. In no case was HSV isolated from the CSF. The importance of adequate material for viral diagnosis by the laboratory is emphasized.

Antibodies, Viral↗
PubMed1989

Efficiency of isolation of human rotavirus in primary African green monkey kidney cells.

Out of 212 human rotavirus (HRV) containing fecal specimens, 173 (81.6%) yielded virus on first passage in primary African Green monkey kidney cells (AGMK), while additional 34 specimens, did not yield virus on first passage. However, following blind passages, 18 of the 34 yielded virus in passage levels 2-8, thus raising the overall isolation rate to 90.1%. The isolation rate of HRV strains obtained in embryonic Rhesus monkey kidney cell line (MA-104), was only 41.4%. ELISA tests performed on fluids from infected cell cultures proved to be an efficient tool to measure virus replication. No differences were encountered in the isolation rates between subgroup I and II strains, while viruses lacking the antigenic determinants of both subgroups did not grow at all. However, one of those unusual group A strains was isolated and grew well in AGMK cells. Primary AGMK and MA-104 cells supported the growth of tissue culture adapted virus most efficiently when compared with six human and primate cell types.

Animals↗
PubMed1988

Use of polyclonal and monoclonal antibodies and analysis of viral RNA in the detection of unusual group A human rotaviruses.

Immuno-enzymatic assay employing monoclonal antibodies and viral RNA analysis by gel electrophoresis were used to classify human group A rotaviruses (HRV) into subgroups I and II. Of 249 fecal samples positive for group A rotaviruses, 29 (11%) belonged to subgroup I and 215 (85%) were identified as subgroup II. Two samples (Ro-302 and Ro-500) contained mixed infections of the two subgroups. Three isolates belonged to neither one of the two subgroups, but they did not yield enough viral RNA to allow their classification. One subgroup I isolate (Ro-1845) contained components typical of subgroup II viruses in that it was identical to serotype 3 and yielded RNA with fast-moving 10th and 11th segments. After growth in culture, the two mixed infections yielded subgroup II viruses, which were identified as serotype 1. The three unclassified isolates grew poorly in culture and could not be further analyzed. The subgroup I isolate (Ro-1845) grew well in culture and yielded virus similar to the original one.

Antibodies↗
PubMed1988

Isolation of HIV from Israeli patients and asymptomatic carriers.

Human immunodeficiency virus (HIV 1) strains were isolated from peripheral blood lymphocytes of eight homosexual men (two asymptomatic and six with lymphadenopathy syndrome) and of the wife of an AIDS patient with AIDS-related complex. All except one had antibodies to HIV in their serum. Virus isolation was carried out by cocultivation of the donors' peripheral lymphocytes with HUT-78 cells or with phytohemagglutinin-stimulated normal cord blood lymphocytes. Identification of the virus was based on detection of specific cytopathogenic effects, determination of reverse transcriptase activity, specific immunofluorescence and Southern blot analysis of HIV proviral DNA in the infected cell cultures.

AIDS-Related Complex↗
PubMed1988

Immune changes in male homosexuals--predisposing factors for HIV seroconversion.

Israel is still a low incidence country for AIDS and thus the temporal relationships between various cofactors and HIV infection can be more easily determined. We have studied a cohort of 243 asymptomatic male homosexuals (MHS) during the last 4 years. At the beginning of the study, 40% had significant decreases in the peripheral blood lymphoid populations, signs for reactivation of CMV and EBV infections, and elevated serum levels of interferon. There was no difference in the prevalence of these immune derangements between seropositive and seronegative individuals. In the course of 4 years' follow-up, the prevalence of these immune derangements has remained the same though being significantly more severe in the HIV seropositive subjects. HIV seroconversion did not exceed 8% (about 2% annually) and was related to the immune impairments found when first seen at the beginning of the study. The results suggest that immune impairments are common among asymptomatic MHS, precede HIV infection, and probably contribute to the increased risk for AIDS among male homosexuals.

Antibodies, Viral↗
PubMed1987

Detection of varicella-zoster virus in lymphocytes by DNA hybridization.

The availability of cloned varicella-zoster virus (VZV) DNA probes allows rapid detection of viral-specific DNA by "dot-blot" hybridization in lymphocytes or in lesion aspirates. Thirty-six blood specimens were obtained from 25 patients with suspected varicella or zoster. VZV-specific DNA was demonstrated in 15 lymphocyte preparations of nine patients with varicella and in one with disseminated zoster out of five patients with zoster. VZV-specific DNA was detected prior to rise in antibodies, indicating early viremia in these patients. Virus isolation from lesions and serological tests confirmed VZV infections. VZV-specific DNA was detected in lymphocytes of three patients out of six with active herpetic lesions, whereas it was not detected in lymphocyte specimens from two patients with undiagnosed rash or four with lymphoproliferative diseases, who did not present varicella or zoster, or from 18 healthy controls. No signal was obtained in herpes simplex virus (HSV)-infected and -uninfected cell lines. The hybridization assay proved that specific and viral or cellular DNAs other than VZV did not cross-hybridize with the probe. The sensitivity limit of detection was 4-15 pg of homologous DNA, and the assay was accomplished within 72-96 hr. These results point to the possible rapid diagnosis of VZV infection in patients suspected of varicella or generalized zoster. In addition, simultaneous infection with both VZV and HSV seems to occur in some patients.

Adolescent↗
PubMed1987

Sensitivity in vitro of herpes simplex virus isolates to human fibroblast interferon.

Sensitivity of herpes simplex virus (HSV) isolates, from patients with recurrent infections, to human fibroblast beta interferon (IFN), was tested in vitro. Among 25 HSV strains, 12 were HSV-1, isolated from facial and labial lesions, and 13 were HSV-2 isolated from genital lesions. Viral sensitivity to IFN was examined on epithelial MB cell line by yield reduction and plaque reduction and close correspondence between the two methods was observed. Most of HSV-1 isolates were in the same range of sensitivity to IFN, while HSV-2 isolates varied in sensitivity and differences approached statistical significance (P = 0.14). No correlation was found between various biological properties, such as plaque size, virulence in baby mice, growth at different temperatures, thymidine kinase activity in the presence or absence of IFN and sensitivity to IFN. Application of beta IFN containing cream reduced clinical symptoms in most of the patients. However, larger numbers of patients should be evaluated in order to conclude whether in vitro sensitivity correlates to clinical improvement.

Adult↗
PubMed1987

Detection of CMV in urine: comparison between DNA-DNA hybridization, virus isolation, and immunoelectron microscopy.

Rapid detection of CMV-DNA in urine specimens by dot-blot hybridization was compared to conventional virus isolation and to virus identification using solid-phase immunoelectron microscopy (SPIEM). To detect viral DNA, 32P-labeled EcoR1 J fragment of CMV-DNA was used as a probe in the hybridization assay. In addition, DNA extracted from infected human embryo fibroblasts (amplified DNA) was also hybridized to the same probe. Urine specimens were obtained from 10 renal transplanted patients, seven premature infants, three family members, and five children suspected of CMV infection. CMV was isolated from 10 urine specimens and SPIEM detected viral particles in nine specimens. Ten positive samples were identified as such by hybridization with DNA extracted directly from urine specimens, while hybridization with amplified DNA yielded 17 positives. Only in one urine specimen, positive by virus isolation and SPIEM, DNA was not detected by the hybridization assays. Elevated IgG or IgM-specific antibodies were found in 10 patients. Hybridization with amplified DNA proved the most sensitive and relatively rapid assay, as compared with direct DNA detection in urine, tissue culture isolation, SPIEM, or serologic tests.

Adult↗
PubMed1987

Nasopharyngeal carcinoma in Israel: epidemiology and Epstein-Barr virus-related serology.

Epidemiological, histological and serological characteristics of nasopharyngeal carcinoma (NPC) were investigated. Included were 25 patients aged 10-70 with male to female ratio 2:1. Among 23 Jewish patients, 18 were of Asian-African (AA) and five of European (Eur) descent; two were Arabs (Ar). The dominant histological type among AA patients was undifferentiated carcinoma (UCNT) and among Eur squamous cell carcinoma (SCC). Elevated IgG and IgA antibodies to Epstein-Barr (EBV) viral capsid, early and nuclear antigens were observed in patients, as compared to 34 healthy controls matched by age, sex and ethnic origin. Although not statistically significant, antibodies to EBV were elevated in AA, as compared to Eur patients. No significant differences in IgG and IgA antibodies to Herpes simplex, Cytomegalo and Varicella-zoster viruses were demonstrated among patients and controls. The study suggests that NPC in Israel, as elsewhere, is associated with EBV and genetic or environmental factors may influence the prevalence of NPC among certain ethnic groups.

Adolescent↗
PubMed1987

Molecular analysis of Burkitt's leukemia in two hemophilic brothers with AIDS.

In two hemophilic brothers infected by the human immunodeficiency virus (HIV), Burkitt's leukemia developed within 1 year. Both patients were treated by aggressive chemotherapy, and both are still in complete remission for 23 and 14 months, respectively. Sera from both brothers contained anti-HIV antibodies. However, DNA extracted from the tumor cells, when analyzed by Southern blot using a cloned HIV probe, did not reveal HIV-related sequences. Hybridization experiments with an Epstein-Barr virus (EBV) probe revealed the presence of EBV-specific sequences in the tumors' DNA. In both patients' tumors rearranged c-myc genes were found. The rearrangements occurred in both genes 3' to the third exon of c-myc, thereby suggesting that a variant chromosomal translocation took place in both cases. Indeed, karyotype analysis of the malignant cells of one of the patients revealed the variant t(2:8) translocation. In contrast to the majority of Burkitt's tumors carrying this translocation, which are kappa light-chain producers, cells of our patient expressed lambda chains. Furthermore, in both cases the lymphoblasts carried IgG on the surface, again an unusual finding in Burkitt's tumors. Finally, because both patients had an identical HLA phenotype, the role of genetic factors in the development of such tumors should be considered.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Importance of the concomitant presence of palpable MOPC-315 tumor in stimulation of splenocytes by C-type MOPC-315 virus in vitro.

BALB/c mice inoculated with MOPC-315 tumor cells developed an antiviral response against C-type particles extracted from subcutaneous tumors of plasmacytoma-bearing mice as shown by in vitro stimulation of spleen cells from tumor-bearing mice by virus-containing preparations. Induction of blastogenic response by virus-containing preparations was found to occur in unfractionated spleen cell populations, the glass-wool non-adherent fraction (depleted of macrophages and tumor cells) and the nylon-wool non-adherent (T-enriched) fraction of spleen cells. The antiviral response was no more detectable in spleens of tumor-bearing mice cured by melphalan. Cured mice developed a strong antitumor immune response as shown by their resistance to challenge with a tumorigenic dose of MOPC-315 tumor cells. However, challenge with tumor cells of cured, resistant mice did not induce reappearance of antiviral response.

Animals↗