Effective detection of human adenovirus in hawaiian waters using enhanced pcr methods

<p>Abstract</p> <p>Background</p> <p>The current criteria for recreational water quality evaluation are primarily based on measurements of fecal indicator bacteria growth. However, these criteria often fail to predict the presence of waterborne human pathogenic viruses. To explore the possibility of direct use of human enteric viruses as improved human fecal contamination indicators, human adenovirus (HAdV) was tested as a model in this study.</p> <p>Findings</p> <p>In order to establish a highly sensitive protocol for effective detection of HAdV in aquatic environments, sixteen published PCR primer sets were re-optimized and comparatively evaluated. Primer sets nehex3deg/nehex4deg, ADV-F/ADV-R, and nested PCR primer sets hex1deg/hex2deg and nehex3deg/nehex4deg were identified to be the most sensitive ones, with up to 1,000 fold higher detection sensitivity compared to other published assays. These three PCR protocols were successfully employed to detect HAdV in both treated and untreated urban wastewaters, and also in 6 of 16 recreational water samples collected around the island of Oahu, Hawaii.</p> <p>Conclusions</p> <p>Findings from this study support the possible use of enteric viruses for aquatic environmental monitoring, specifically for the essential routine monitoring of Hawaiian beach waters using the optimized PCR protocol to detect HAdV at certain water sites to ensure a safe use of recreational waters.</p

Mycobacterium phlei cell wall complex directly induces apoptosis in human bladder cancer cells

Intact mycobacteria and mycobacterial cell wall extracts have been shown to inhibit the growth of human and murine bladder cancer. Their mechanism of action is, however, poorly understood. Mycobacterium phlei mycobacterial cell complex (MCC) is a cell wall preparation that has mycobacterial DNA in the form of short oligonucleotides complexed on the cell wall surface. In this study, we have investigated the possibility that MCC has anti-cancer activity that is mediated by two different mechanisms – a direct effect on cancer cell proliferation and viability and an indirect effect mediated by the production of interleukin 12 (IL-12), a cytokine known to possess anti-cancer activity. We have found that, although MCC is a potent inducer of IL-12 and IL-6 synthesis in monocytes and macrophages either in vitro or in vivo, it is unable to induce the synthesis of either IL-12, IL-6 or granulocyte–macrophage colony-stimulating factor (GM-CSF) by the human transitional bladder cancer cell lines HT-1197 and HT-1376. MCC is not directly cytotoxic towards these cancer cells, but induces apoptosis as determined by nuclear DNA fragmentation and by the release of nuclear mitotic apparatus protein. Mycobacterium phlei DNA associated with MCC is responsible for the induction of apoptosis. Our results indicate that MCC directly effects bladder cancer cells by inhibiting cellular proliferation through the induction of apoptosis, and has the potential for an indirect anti-cancer activity by stimulating cancer-infiltrating monocytes/macrophages to synthesize IL-12. © 1999 Cancer Research Campaig

Effect of the pH and osmolality of urine on the antibacterial activity of gentamicin

The antibacterial activity of gentamicin against five strains each of Escherichia coli and Pseudomonas aeruginosa was followed by kinetic killing studies. Human urine having a variable osmolality and adjusted to pH 5.0 or 6.0 was used. Gentamicin was added at a final concentration of 10 or 50 mg/l. It was shown that human urine inhibited the action of gentamicin and that effect was enhanced in acid urine and depressed when the osmolality of the urine was lower. The pH and osmolality of urine variably affected the activity of gentamicin depending on the bacterial species. Lower osmolality rendered Ps. aeruginosa strains more easily susceptible to gentamicin as compared to E. coli. The data of the present study may be useful in clinical practice in the treatment of urinary infections; in cases of urine with low osmolality relatively low doses of gentamicin might be sufficient. In contrast, problems may be encountered in urinary infections in patients with renal insufficiency where reduced dosage of the drug is suggested. In those cases dilution and alkalinization of urine would be beneficial. © 1983 The British Society for Antimicrobial Chemotherapy