The diversity and dominant bacterial taxa in the vagina are reported to be influenced by multiple intrinsic and extrinsic factors, including but not limited to pregnancy, contraceptive use, pathogenic states, socioeconomic status, and ancestry. However, the extent to which host genetic factors influence variation in the vaginal microbiota is unclear. We used a biometrical genetic approach to determine whether host genetic factors contribute to inter-individual differences in taxa from a sample of 332 twins who self-identified as being of African (44 pairs) or European ancestry (122 pairs).
View Article and Find Full Text PDFTriclosan (2,4,4'-trichloro-2'-hydroxy-diphenyl ether) is an antibacterial compound that has been used in consumer products for about 40 years. The tolerability and safety of triclosan has been evaluated in human volunteers with little indication of toxicity or sensitization. Although information in humans from chronic usage of personal care products is not available, triclosan has been extensively studied in laboratory animals.
View Article and Find Full Text PDFA recent study in rats investigated the retail sweetener product, Granulated SPLENDA No Calorie Sweetener (Splenda) (Abou-Donia et al., 2008. Splenda alters gut microflora and increases intestinal P-glycoprotein and cytochrome P-450 in male rats.
View Article and Find Full Text PDFRegul Toxicol Pharmacol
October 2007
A set of biologically-based toxicity testing decision triggers was developed and analyzed within a tiered testing and decision-making framework for evaluating potential human health hazards and risks associated with chemical exposures. The proposed three-tiered toxicity testing approach starts from a base set of toxicity studies (acute toxicity, in vitro genetic toxicity, in vitro cytogenetics, repeat dose/subchronic toxicity, developmental toxicity, reproductive toxicity) and then uses the toxicity triggers to identify which specific additional tests are needed to adequately characterize a substance's hazard potential. The toxicity triggers were initially evaluated using published information for eight chemicals, representing diverse classes.
View Article and Find Full Text PDFMultiple renal tubular cell adenomas and atypical tubular hyperplasia were diagnosed in 2 high-dose and 1 mid-dose female Sprague-Dawley (Crl:CD (SD)IGS BR) rats from a 90-day toxicity study of an amino acid found in green tea. The tumors were bilateral multicentric adenomas accompanied by atypical foci of renal tubular hyperplasia in both kidneys of the 3 animals. Toxic tubular changes that typically accompany renal carcinogenesis were not seen in any of the other animals of the study, suggesting rather, an underlying germline mutation of a tumor suppressor gene in these three rats.
View Article and Find Full Text PDFOne of the principal applications of toxicology data is to inform risk assessments and support risk management decisions that are protective of human health. Ideally, a risk assessor would have available all of the relevant information on (a) the toxicity profile of the agent of interest; (b) its interactions with living systems; and (c) the known or projected exposure scenarios: to whom, how much, by which route(s), and how often. In practice, however, complete information is seldom available.
View Article and Find Full Text PDFFood Chem Toxicol
March 2007
The present oral embryotoxicity/teratogenicity study of d-Ribose (DR) was conducted in female rats; 28 rats/group were exposed via the diet to 0, 5, 10, or 20% DR (0.0, 4.25, 7.
View Article and Find Full Text PDFFood Chem Toxicol
January 2007
The present study evaluated the toxicity from sub-chronic administration of D-ribose (DR) to male and female albino Wistar rats. Groups of 20 male and 20 female rats were exposed via the diet to 0%, 5%, 10%, or 20% DR, seven days per week (mean daily intake of 0.0, 3.
View Article and Find Full Text PDFFood Chem Toxicol
September 2004
With the approval for use in foods in Japan and the United States, the use of diacylglycerol (DAG) oil in fat-based products may become extensive due to equivalent physicochemical properties to conventional triacylglycerol (TAG) oil. The objective of the present study was to compare the effects of high-dose consumption of DAG oil in humans with that of TAG oil. In a double-blind controlled parallel trial, moderately lean men (n=42) and women (n=39) consumed either DAG or TAG at a dose of approximately 0.
View Article and Find Full Text PDFStudies were conducted to assess the safety of N-alpha-lauroyl-L-arginine ethyl ester monohydrochloride, (LAE), a novel food preservative, or Mirenat-N (a 25% solution of LAE in propylene glycol). Short term studies demonstrated low acute toxicity. LAE was shown to have mild dermal irritation effects but neither LAE nor Mirenat-N are skin sensitizers.
View Article and Find Full Text PDFNitrogen oxides (NO(x)) are ubiquitous pollutants in outdoor and indoor air. However, epidemiologic studies that evaluate health effects associated with NO(x) commonly rely upon outdoor concentrations of NO(x), nitrogen dioxide (NO(2)), or residence characteristics as surrogates for personal exposure. In this study, personal exposures (48 h) and corresponding indoor and outdoor concentrations of nitric oxide (NO), NO(2), and NO(x) were measured (July-September) in 39 adults and 9 children from 23 households in Richmond, Virginia, using Ogawa passive NO(x) monitors.
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