Helmut A. Greim

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Many wildlife species may be exposed to biologically active concentrations of endocrine-disrupting chemicals. There is strong evidence obtained from laboratory studies showing the potential of several environmental chemicals to cause endocrine disruption at environmentally realistic exposure levels. In wildlife populations, associations have been reported(More)
Contents of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and of 16 further congeners – polychlorinated dibenzodioxins and dibenzofuranes (PCDD/PCDF) – were determined in lipids of adipose tissue and of livers of 3 stillborns and of 17 infants (0.43–44 weeks old) who died from sudden infant death syndrome. International toxic equivalents (I-TEq) calculated for(More)
Inflammatory stimulation of the liver leads to the induction of nitric oxide (NO) biosynthesis. Because NO binds to the catalytic heme moiety of cytochromes P450 (CYPs), we investigated whether NO interferes with specific CYP-dependent metabolic pathways. In a first experimental approach V79 Chinese hamster cells genetically engineered for stable expression(More)
Male Sprague-Dawley rats (240–245 g) were dosed ip with 5, 15, 25, or 125 μg/kg -,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in corn oil. Ad libitumfed and pair-fed controls received vehicle (4 ml/kg) alone. Two or 8 days after dosing five rats of each group were sacrificed, their livers removed and assayed for the activities of three gluconeogenic enzymes(More)
1. During incubation of 14CCl4, 14CHCl3, [14C]halothane, or 14CCl3F with liver microsomes and NADPH, considerable radioactivity is bound irreversibly to endoplasmic protein and lipid. However, no 14C was detected in the ribosomal RNA. 2. None of the four haloalkanes studied induced mutations after incubation with liver microsomes and the bacterial tester(More)
Brominated dibenzo-p-dioxins and dibenzofurans can be formed under laboratory conditions by pyrolysis of flame retardants based on polybrominated biphenyls and biphenyl ethers. Their occurrence in the environment, however, is due to combustion processes such as municipal waste incineration and internal combustion engines. As these processes generally take(More)
PURPOSE Titanium endosseous implants are becoming increasingly important in dentistry because of their excellent long-term results. However, it has been reported that these implants may lead to higher concentrations of titanium, especially in the lungs and kidneys. The purpose of this study, therefore, was to determine whether CO2 laser-assisted(More)
Abstract Glyphosate, an herbicidal derivative of the amino acid glycine, was introduced to agriculture in the 1970s. Glyphosate targets and blocks a plant metabolic pathway not found in animals, the shikimate pathway, required for the synthesis of aromatic amino acids in plants. After almost forty years of commercial use, and multiple regulatory approvals(More)