Biomedical subjects

M Jiwa

Publications and source records attributed to M Jiwa.

23 records · Page 2Linked to original sources

PubMed1990

Detection of human papillomavirus and Epstein-Barr virus DNA sequences in oral mucosa of HIV-infected patients by the polymerase chain reaction.

The presence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) was analyzed in 21 oral biopsy specimens of HIV-infected patients using the polymerase chain reaction (PCR) method. Biopsies were categorized as hairy leukoplakia (HL) (n = 12), candidiasis (n = 3), oral warts (n = 2), and clinically normal epithelium (n = 4). For HPV detection a modified general primer-mediated PCR method (GP-PCR), which detects a broad spectrum of HPV genotypes at sub-picogram levels, was used. Human papillomavirus DNA was only found in two oral warts and was identified as HPV type 32. Epstein-Barr virus DNA was detected in 16 biopsy specimens, including the 12 HLs, 2 cases of candidiasis, and 2 samples of normal epithelium. Epstein-Barr virus positivity in HL could be confirmed by Southern blot analysis and DNA in situ hybridization using biotinylated DNA probes (bio-DISH). Epstein-Barr virus bio-DISH was also positive in one sample of normal epithelium from a patient with HL. The results indicate that HL is strongly associated with EBV and not with any of the common HPV types that react with general HPV primers in the PCR. However the detection of EBV in normal oral epithelium by PCR and bio-DISH suggests that the presence of this virus is not exclusively related to HL.

Base Sequence↗

PubMed1989

Implausibility of an aetiological association between cytomegalovirus and Kaposi's sarcoma shown by four techniques.

The presence of cytomegalovirus (CMV) was analysed in either lymph node or skin and lung tissue necropsy specimens affected by Kaposi's sarcoma, from 10 patients who had died of AIDS. The different detection techniques used were: (i) immunohistochemical demonstration of CMV immediate early antigen (IEA); (ii) in situ hybridisation with a biotinylated CMV DNA probe; (iii) Southern blot hybridisation of DNA extracted from sequential tissue sections; and (iv) polymerase chain reaction (PCR) with CMV specific primers on the DNA samples. The results of these analyses were compared with the postmortem data on CMV obtained by infectious particle assays and histological examination, especially of adrenal glands of the same patients. The results of the various detection methods correlated very well, yielding a combined score of six of 10 patients positive for CMV; there did not seem to be any association between the presence of CMV and the occurrence of Kaposi's sarcoma in our patients.

Antigens, Viral↗

PubMed1988

Analysis and isolation of cytomegalovirus DNA by field inversion gel electrophoresis.

High molecular weight human cytomegalovirus (CMV) DNA was isolated from agarose-embedded infected human diploid cells by employing field inversion gel electrophoresis. A high yield of CMV DNA molecules was obtained within 1 week of infecting the cell culture. Labelling of the viral DNA with biotin by nick translation enabled the detection of CMV-infected cells in sections of paraffin-embedded human adrenal gland by in situ hybridization.

Adrenal Glands↗

PubMedDate not supplied

The possible role of stromal influences in tumor cell heterogeneity. Histology and fibronectin pattern of the Yoshida sarcoma of the rat.

Yoshida tumors implanted subcutaneously in the rat are conspicuously heterogeneous. A definite zoning can be discerned. Cell nuclei range from uniform epitheloid (type I) via pleomorphic (type II) to compact (type III). Type III is seen to detach at the rim of the tumor and to infiltrate the dermis. Type I is characterized by positive pericellular fibronectin staining, type II and III are fibronectin-negative. A marked spatial relationship was seen between types II and III on one hand and the presence of collagenous stroma on the other. It is conjectured that stromal components play a role in tumor promotion or progression.

Animals↗

PubMedDate not supplied

Interaction with host stroma as a promotional factor in tumor malignancy.

Cells of a Yoshida sarcoma implanted subcutaneously in the rat are heterogeneous. Nuclei vary microscopically from regularly vesicular to irregular and hyperchromatic. Cells with hyperchromatic nuclei are in remarkably close association with stromal elements. This finding is consistent with the theory that stromal influences have a promotional effect on tumor cells. The nature of the hypothetical factor is conjectural.

Animals↗