Chemicals present in automobile traffic tunnels and the possible community health hazards: a review of the literature.

Dozens of volatile and semivolatile organic compounds can be detected in vehicle exhaust, along with numerous metals and oxides of sulfur, nitrogen, and carbon. While the adverse effects of these chemicals have been extensively studied surrounding open roadways, the hazards to local residents and commuters resulting from the presence of tunnel emission chemicals are less well known. Commuters and workers within tunnels are also exposed to tunnel atmospheres, and the risks have only been evaluated to a limited extent.

DNA-protein cross-links in erythrocytes of freshwater fish exposed to hexavalent chromium or divalent nickel.

DNA-protein cross-links (DPXs) in fish erythrocytes represent a potential biomarker for exposure to metal cations, such as hexavalent chromium (Cr[VI]) and divalent nickel (Ni[II]). Species-specific sensitivities to DPX formation were studied by coexposure of juvenile specimens of rainbow trout, hybrid bluegill, and channel catfish to waterborne metals, such as Cr(VI) and Ni(II). In a species comparison, 4 days of exposure to 2 ppm Cr(VI) induced highest DPXs in bluegill erythrocytes, followed by trout and catfish, at 186%, 97%, and 48% above controls, respectively.

1-Methylnicotinamide stimulates cell growth and inhibits hemoglobin synthesis in differentiating murine erythroleukemia cells.

Exposure of murine erythroleukemia cells (MELCs) to nicotinamide (NA) or its synthetic analog N'-methylnicotinamide (N'-MN) reduces cell growth and induces terminal differentiation, marked by increased heme and globin accumulation. On the contrary, 1-methylnicotinamide (1-MN), the primary metabolite of excess NA, was found to stimulate cell growth and reduce spontaneous differentiation of cultured MELCs. Log phase MELCs exhibited up to 50% higher cell density above untreated cells when cultured for up to 96 h with 2.

Waterborne and dietary hexavalent chromium exposure causes DNA-protein crosslink (DPX) formation in erythrocytes of largemouth bass (Micropterus salmoides).

Formation of DNA-protein crosslinks (DPXs) was demonstrated in erythrocytes from fathead minnows (Pimephales promelas) and largemouth bass (Micropterus salmoides) exposed to hexavalent chromium [Cr(VI)], a known carcinogenic and mutagenic metal contaminant of many industrial waterways. Tank water exposure of 2-3 in. fathead minnows to 2 ppm Cr(VI) led to significant DPX formation in erythrocytes, with over 140-200% elevations above background levels at 3-4 days, respectively.

Stability of phenytoin sodium suspensions for the treatment of open wounds.

The objective of this study was to evaluate the stability of two phenytoin sodium suspensions in 0.9% sodium chloride solution for use in noninstitutional settings (where pharmacies are not present) to dispense phenytoin on a daily basis. A generic extended phenytoin sodium (Mylan) and a name brand phenytoin sodium (Dilantin) in suspension form were evaluated.

5-azacytidine and decitabine monotherapies of myelodysplastic disorders.

Objective: To review and differentiate the pharmacology, toxicology, pharmacokinetics, and results of major clinical trials of 5-azacytidine (5-AzaC) and 5-aza-2'-deoxycytidine (decitabine) therapy of myelodysplastic disorders.

Data Sources: A PubMed/MEDLINE search was conducted (1966-October 2004) using the following terms: DNA methylation, myelodysplastic disorders, 5-azacytidine, and 5-aza-2'-deoxycytidine (decitabine). Additional data sources included bibliographies from identified articles and manufacturer information.

Possible warfarin failure due to interaction with smokeless tobacco.

Objective: To report a case of possible interaction of smokeless tobacco with warfarin in a patient treated after several thromboembolic events.

Case Summary: A white man with a long history of smokeless tobacco use was unsuccessfully treated with warfarin up to 25-30 mg/day. International normalized ratio (INR) values never stabilized >2.