Guenter Speit

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A.Hartmann1,12, E.Agurell2, C.Beevers3, S.Brendler-Schwaab4, B.Burlinson5, P.Clay6, A.Collins7, A.Smith8, G.Speit9, V.Thybaud10 and R.R.Tice11 1Novartis Pharma AG, Nervous Systems PRIDE, WSJ106.2.42, CH-4002 Basel, Switzerland, 2AstraZeneca R&D Södertälje, Safety Assessment, S-151 85 Södertälje, Sweden, 3Inventures, 1 Trevelyan Square, Boar Lane, Leeds LS1(More)
As part of the Fourth International Workshop on Genotoxicity Testing (IWGT), held 9-10 September 2005 in San Francisco, California, an expert working group on the Comet assay was convened to review and discuss some of the procedures and methods recommended in previous documents. Particular attention was directed at the in vivo rodent, alkaline (pH >13)(More)
At a recent ECVAM workshop considering ways to reduce the frequency of irrelevant positive results in mammalian cell genotoxicity tests [D. Kirkland, S. Pfuhler, D. Tweats, M. Aardema, R. Corvi, F. Darroudi, A. Elhajouji, H.-R. Glatt, P. Hastwell, M. Hayashi, P. Kasper, S. Kirchner, A. Lynch, D. Marzin, D. Maurici, J.-R. Meunier, L. Müller, G. Nohynek, J.(More)
Formaldehyde (FA) was tested for its genotoxicity in human blood cultures. We treated blood samples at the start of the culture to follow FA-induced DNA damage (DNA-protein crosslinks, DPX), its repair and its genetic consequences in form of sister chromatid exchanges (SCE) and micronuclei (MN). Our results clearly indicate that DPX (determined by the comet(More)
Formaldehyde (FA) is a genotoxic substance, induces tumors in the nasal epithelium of rats, and is suspected to be a human carcinogen. As a primary DNA lesion, FA induces DNA-protein crosslinks (DPC) and the formation of DPC has been used as a measure of exposure for risk estimation. However, the significance of DPC for mutagenesis and carcinogenesis is at(More)
Enhanced sensitivity to the chromosome-damaging effects of ionizing radiation is a feature of many cancer-predisposing conditions. It has been suggested that women with breast cancer are deficient in the repair of radiation-induced DNA damage. We have now investigated whether mutagen sensitivity is related to mutations in the breast cancer gene BRCA1. We(More)
Formaldehyde (FA) is genotoxic in vitro in cultured mammalian cells. When FA reaches the nuclear DNA, it forms DNA-protein cross-links (DPX). Incomplete repair of DPX can lead to the formation of mutations, in particular chromosome mutations and micronuclei (MN) in proliferating cells. Due to its high reactivity, FA leads primarily to local genotoxic(More)
We evaluated genotoxic and cytotoxic effects of the three non-mutagenic and non-carcinogenic compounds p-nitrophenol, D-menthol and sodium N-lauroyl sarcosine which have previously been shown to induce DNA double strand breaks (DNA dsb) secondary to induced cytotoxicity. We tested whether genotoxic effects in the alkaline single cell gel test (comet assay)(More)
The in vivo comet assay (single cell gel electrophoresis assay) in its alkaline version (pH >13) is being increasingly used in genotoxicity testing of substances such as industrial chemicals, biocides, agrochemicals, food additives and pharmaceuticals. Recommendations for an appropriate performance of the test using OECD guidelines for other in vivo(More)