Hepatitis B--are surgeons putting patients at risk? (9/26780)

The 1993 Department of Health guidelines permit a surgeon who is hepatitis B surface antigen (HBsAg) positive but e-antigen (HBeAg) negative to perform exposure prone procedures, unless demonstrated to have infected patients. However, there is increasing evidence of transmission of hepatitis B to patients from health care workers in this supposedly low infectivity category. The Occupational Physician must decide whether existing guidelines represent an adequate risk assessment and indeed whether this is an acceptable risk for patients. If an NHS Trust continues to follow these guidelines it may be in breach of its duty of care to patients. Yet refusing to allow such carriers to operate without testing for additional serological markers may be unlawful discrimination. Further research is clearly needed as well as an urgent review of the guidelines.  (+info)

Association of simian virus 40 with a central nervous system lesion distinct from progressive multifocal leukoencephalopathy in macaques with AIDS. (10/26780)

The primate polyomavirus SV40 is known to cause interstitial nephritis in primary infections and progressive multifocal leukoencephalopathy (PML) upon reactivation of a latent infection in SIV-infected macaques. We now describe a second central nervous system manifestation of SV40: a meningoencephalitis affecting cerebral gray matter, without demyelination, distinct from PML. Meningoencephalitis appears also to be a primary manifestation of SV40 infection and can be seen in conjunction with SV40-induced interstitial nephritis and pneumonitis. The difference in the lesions of meningoencephalitis and PML does not appear to be due to cellular tropism, as both oligodendrocytes and astrocytes are infected in PML and meningoencephalitis, as determined by in situ hybridization or immunohistochemistry for SV40 coupled with immunohistochemistry for cellular determinants. This is further supported by examination of SV40 nucleic acid sequences from the ori-enhancer and large-T-antigen regions, which reveals no tissue-or lesion-specific variation in SV40 sequences.  (+info)

Detection of Chlamydia pneumoniae but not cytomegalovirus in occluded saphenous vein coronary artery bypass grafts. (11/26780)

BACKGROUND: A causal relation between atherosclerosis and chronic infection with Chlamydia pneumoniae and/or cytomegalovirus (CMV) has been suggested. Whether the unresolved problem of venous coronary artery bypass graft occlusion is related to infection with C pneumoniae and/or CMV has not been addressed. METHODS AND RESUTLS: Thirty-eight occluded coronary artery vein grafts and 20 native saphenous veins were examined. Detection of C pneumoniae DNA was performed by use of nested polymerase chain reaction (PCR). Homogenisates from the specimen were cultured for identification of viable C pneumoniae. Both conventional PCR and quantitative PCR for detection of CMV DNA were applied. Differential pathological changes (degree of inflammation, smooth muscle cell proliferation [MIB-1]) were determined and correlated to the detection of both microorganisms. C pneumoniae DNA could be detected in 25% of occluded vein grafts. Viable C pneumoniae was recovered from 16% of occluded vein grafts. Except for 1 native saphenous vein, all control vessels were negative for both C pneumoniae detection and culture. All pathological and control specimens were negative for CMV DNA detection. Pathological changes did not correlate with C pneumoniae detection. CONCLUSIONS: Occluded aorto-coronary venous grafts harbor C pneumoniae but not CMV. The detection of C pneumoniae in occluded vein grafts warrants further investigation.  (+info)

Mayaro virus disease: an emerging mosquito-borne zoonosis in tropical South America. (12/26780)

This report describes the clinical, laboratory, and epidemiological findings on 27 cases of Mayaro virus (MV) disease, an emerging mosquito-borne viral illness that is endemic in rural areas of tropical South America. MV disease is a nonfatal, dengue-like illness characterized by fever, chills, headache, eye pain, generalized myalgia, arthralgia, diarrhea, vomiting, and rash of 3-5 days' duration. Severe joint pain is a prominent feature of this illness; the arthralgia sometimes persists for months and can be quite incapacitating. Cases of two visitors from the United States, who developed MV disease during visits to eastern Peru, are reported. MV disease and dengue are difficult to differentiate clinically.  (+info)

Increased levels of human papillomavirus type 16 DNA in a subset of prostate cancers. (13/26780)

Whether oncogenic human papilloma viruses (HPVs) are involved in the pathogenesis of prostate cancers has been a subject of great controversy. To clarify the contradictory results of investigations, with the aim of detecting viral nucleic acids in prostate cancers, we have carried out a comparative quantitation of the HPV16-E6 sequence in 84 prostate specimens. Using single-tube quantitative competitive PCR, we characterized 47 prostate cancers and 37 control tissues of benign prostatic hyperplasia. A subgroup of the prostate tumors (10 of 47; 21%) was detected as having significantly higher copy numbers of HPV16-E6 sequences when compared to the control tissue (1 of 37; 3%), using a cutoff value of 300 copies per 12,500 diploid cells (two-sided Fisher's exact test, P = 0.02). Our results indicate that the oncogenic HPV16 might contribute to the development of a subset of prostate tumors.  (+info)

Detection of Kaposi's sarcoma herpesvirus DNA sequences in multiple myeloma bone marrow stromal cells. (14/26780)

Whether Kaposi's sarcoma herpesvirus (KSHV) is associated with multiple myeloma (MM) remains controversial. We assayed for KSHV DNA sequences in long-term bone marrow stromal cells (BMSCs) from 26 patients with MM and 4 normal donors. Polymerase chain reaction (PCR) using primers which amplify a KSHV gene sequence to yield a 233-bp fragment (KS330233 within open reading frame 26) was negative in all cases. Aliquots of these PCR products were used as templates in subsequent nested PCR, with primers that amplify a 186-bp product internal to KS330233. BMSCs from 24 of 26 (92%) patients with MM and 1 of 4 normal donors were KSHV PCR+. DNA sequence analyses showed interpatient specific mutations (2 to 3 bp). Both Southern blot and sequence analyses confirmed the specificity of PCR results. The presence of the KSHV gene sequences was further confirmed by amplifying T 1.1 (open reading frame [ORF] K7) and viral cyclin D (ORF 72), two other domains within the KSHV genome. Immunohistochemical studies of KSHV PCR+ MM BMSCs demonstrate expression of dendritic cell (DC) lineage markers (CD68, CD83, and fascin). Serological studies for the presence of KSHV lytic or latent antibodies were performed using sera from 53 MM patients, 12 normal donors, and 5 human immunodeficiency virus (HIV)/KSHV+ patients. No lytic or latent antibodies were present in sera from either MM patients or normal donors. Taken together, these findings show that KSHV DNA sequences are detectable in BMSCs from the majority of MM patients, but that serologic responses to KSHV are not present. Ongoing studies are defining whether the lack of antibody response is caused by the absence of ongoing infection, the presence of a novel viral strain associated with MM, or underlying immunodeficiency in these patients.  (+info)

Bone marrow and peripheral blood dendritic cells from patients with multiple myeloma are phenotypically and functionally normal despite the detection of Kaposi's sarcoma herpesvirus gene sequences. (15/26780)

Multiple myeloma (MM) cells express idiotypic proteins and other tumor-associated antigens which make them ideal targets for novel immunotherapeutic approaches. However, recent reports show the presence of Kaposi's sarcoma herpesvirus (KSHV) gene sequences in bone marrow dendritic cells (BMDCs) in MM, raising concerns regarding their antigen-presenting cell (APC) function. In the present study, we sought to identify the ideal source of DCs from MM patients for use in vaccination approaches. We compared the relative frequency, phenotype, and function of BMDCs or peripheral blood dendritic cells (PBDCs) from MM patients versus normal donors. DCs were derived by culture of mononuclear cells in the presence of granulocyte-macrophage colony-stimulating factor and interleukin-4. The yield as well as the pattern and intensity of Ag (HLA-DR, CD40, CD54, CD80, and CD86) expression were equivalent on DCs from BM or PB of MM patients versus normal donors. Comparison of PBDCs versus BMDCs showed higher surface expression of HLA-DR (P =.01), CD86 (P =. 0003), and CD14 (P =.04) on PBDCs. APC function, assessed using an allogeneic mixed lymphocyte reaction (MLR), demonstrated equivalent T-cell proliferation triggered by MM versus normal DCs. Moreover, no differences in APC function were noted in BMDCs compared with PBDCs. Polymerase chain reaction (PCR) analysis of genomic DNA from both MM patient and normal donor DCs for the 233-bp KSHV gene sequence (KS330233) was negative, but nested PCR to yield a final product of 186 bp internal to KS330233 was positive in 16 of 18 (88.8%) MM BMDCs, 3 of 8 (37.5%) normal BMDCs, 1 of 5 (20%) MM PBDCs, and 2 of 6 (33.3%) normal donor PBDCs. Sequencing of 4 MM patient PCR products showed 96% to 98% homology to the published KSHV gene sequence, with patient specific mutations ruling out PCR artifacts or contamination. In addition, KHSV-specific viral cyclin D (open reading frame [ORF] 72) was amplified in 2 of 5 MM BMDCs, with sequencing of the ORF 72 amplicon revealing 91% and 92% homology to the KSHV viral cyclin D sequence. These sequences again demonstrated patient specific mutations, ruling out contamination. Therefore, our studies show that PB appears to be the preferred source of DCs for use in vaccination strategies due to the ready accessibility and phenotypic profile of PBDCs, as well as the comparable APC function and lower detection rate of KSHV gene sequences compared with BMDCs. Whether active KSHV infection is present and important in the pathophysiology of MM remains unclear; however, our study shows that MMDCs remain functional despite the detection of KSHV gene sequences.  (+info)

Search for retroviral related DNA polymorphisms using RAPD PCR in schizophrenia. (16/26780)

Random amplification of polymorphic DNA (RAPD) is widely used to detect polymorphisms in many organisms. Individual (or strain) specific amplified bands are generated with single or pairs of primers in PCR reactions and can serve as genetic markers. We have used this method to generate a large number of reproducible bands with single primers, random and retroviral related, on 92 human DNA samples. Theoretically, RAPD PCR presents a logical approach for assessing variability among individuals. We used ten retroviral related primers (12, 20 and 22 bp) and eight random primers (10 bp) to assess individual differences in the context of testing the retroviral hypothesis for schizophrenia. Three pairs of discordant monozygotic twins, four pairs of discordant full sibs and 53 schizophrenic individuals with 25 of their unrelated matched controls were analyzed. Ten of these primers resulted in a total of approx. 850 amplified bands (65-110 bands per primer). Almost all of these bands were identical among each individual analyzed. However, the results are inconclusive with respect to the retroviral hypothesis for schizophrenia. The general lack of RAPD polymorphism in this study may argue for mechanisms other than rearrangements such as inversions, associated with the evolution of the human genome.  (+info)