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J F Régnier

Publications and source records attributed to J F Régnier.

4 recordsLinked to original sources
PubMed1997

IRAG working group 5. Other assays. Interagency Regulatory Alternatives Group.

As part of the Interagency Regulatory Alternatives Group (IRAG) program to evaluate the state of the art in the development of alternative (non-whole animal) eye irritation tests, academic and industrial organizations were invited to submit in vitro eye irritation data generated in their laboratories to one of several working groups for review. The assays reviewed in this report (from Working Group 5. "Other Assays") were the EYTEX assay, tissue equivalent assay, a cytotoxicity assay using three-dimensional human fibroblast constructs, the Microtox assay, and other miscellaneous assays. Each submission consisted of raw data for chemicals and products tested, a description of the methodology, and an analysis (generally by regression analysis and Pearson's correlation coefficient) for the performance of the in vitro test relative to its ability to predict individual ocular tissue scores or total ocular score. In vivo data were generated according to the scoring methods proposed by Draize. Working Group 5 evaluated the submissions and commented on the utility of the assays. The variability of the in vivo data made conclusions difficult in many situations. Most of these assays were deemed useful (within limited chemical classes) for screening purposes or for use in conjunction with other toxicological information.

Animal Testing Alternatives↗
PubMed1994

Genotoxicity studies with chloroethane.

In a recent 2-year inhalation study with F344 rats and B6C3F1 mice conducted as part of the U.S. National Toxicology Program (NTP, 1989), chloroethane (ECl) at an exposure concentration of 15,000 ppm induced a high incidence of endometrial uterine carcinomas only in female mice but not in rats, leading to the conclusion of "clear evidence of carcinogenicity" for the mouse. In order to elucidate whether a genotoxic effect may be a critical factor for the carcinogenicity of ECl in the mouse, we have performed three genotoxicity tests: (1) in vitro HPRT test with CHO cells according to a specially developed gas protocol, (2) in vivo/in vitro UDS with female B6C3F1 mice at an exposure concentration of 25,000 ppm (6 h/day, 3 days), (3) in vivo micronucleus assay with male and female B6C3F1 mice exposed to 25,000 ppm ECl according to the same schedule. In the in vitro HPRT test a mutagenic potential of ECl was detected in the presence as well as in the absence of S9 mix. In contrast, both in vivo test systems failed to detect any indications of genotoxicity of chloroethane at an exposure concentration even higher than that of the NTP study. It is suggested that in vivo the genotoxic potential of ECl is so low that an assumed genotoxic damage is below the detection limit of the test systems used. This leads to the conclusion that genotoxicity may not be a key factor in the induction of the uterine carcinomas in the B6C3F1 mouse.

Animals↗
PubMed1992

Effect of oral administration of 1,3-diphenylguanidine on sperm morphology and male fertility in mice.

An oral testicular toxicity and male fertility study was carried out in CD-1 mice with 1,3-diphenylguanidine (99.9% purity). 1,3-Diphenylguanidine was administered to male mice by daily gavage at dose levels of 0, 0.06, 0.25, 1, 4 and 16 mg/kg body wt. per day during an 8-week premating period. Females were not dosed at any time during the study. Sperm abnormality evaluation was performed in approximately half the males, randomly selected from the control and 16-mg/kg dose group on completion of dosing. The remaining males in the control, 4- and 16-mg/kg body wt per day groups were mated with non-dosed females. Reproductive performance, necropsy findings and litter data were recorded. No differences were found between control and dosed groups in body weight gain during the dosing period, macroscopic observations and organ weights at necropsy. Microscopic examination of the testes and determination of the frequency of total sperm abnormalities in the 16-mg/kg body wt per day group, did not show any effect due to 1,3-diphenylguanidine dosing when compared to the control group, except for a slight increase in sperm with folded tails but normal heads. Male and female fertility as well as reproduction performance were comparable in the groups examined (0, 4 and 16 mg/kg body wt per day). Maternal necropsy findings and litter data did not reveal any dose-related effect. It was concluded that under the conditions of the present study, 1,3-diphenylguanidine did not exert any significant adverse effects on fertility, reproductive capacity or embryonic/fetal development in CD-1 mice when administered to males at levels up to 16 mg/kg body wt per day.

Administration, Oral↗