Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The SCE-test is widely used in genetic toxicology and therefore knowledge of the contribution of BrdU to the formation of spontaneous and induced SCE is of great importance. The present study was undertaken to analyse the role of BrdU in X-ray-induced SCE. If SCE resulted from inversions, rings and double minutes (RDM) would be the asymmetrical counterparts of SCE and should therefore have the same frequencies. Dose-effect relationships of SCE and RDM show that the frequencies of SCE are much higher than those of RDM. We conclude that only a few SCE may represent inversions. In a second set of experiments, endoreduplications were induced in cells irradiated either before or after labelling with BrdU. Analysis of SCE in endoreduplicated chromosomes allows the discrimination of the cell cycle in which they originated. The results show that SCE are only induced in the first cell cycle following irradiation of BrdU-substituted cells, indicating that labelling with BrdU is a necessary prerequisite for the formation of SCE. In order to test this directly, radiation-induced SCE frequencies were studied in cells prelabelled with BrdU or biotin-dUTP in a third set of experiments. The structure of biotin-dUTP suggests that, in contrast to BrdU, it does not give rise to radicals during irradiation. Significantly lower frequencies of SCE were observed in biotin-dUTP-substituted cells than in BrdU-labelled cells. Calculations show that nearly all SCE induced in biotin-dUTP-labelled chromosomes can be explained by chromosomal aberrations (false SCE). In contrast to this, most SCE induced by X-rays in BrdU-labelled cells are not due to chromosomal aberrations, but result from S-dependent lesions (true SCE). This clearly points towards radiation damage in BrdU-moieties as the source of DNA lesions leading to SCE.
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PMID:X-irradiation of G1 CHO cells induces SCE which are both true and false in BrdU-substituted cells but only false in biotin-dUTP-substituted cells. 1046 73

Persistent cervical high-risk human papillomavirus (HPV) infection is correlated with an increased risk of developing a high-grade cervical intraepithelial lesion. A two-step method was developed for detection and genotyping of high-risk HPV. DNA was firstly amplified by asymmetrical PCR in the presence of Cy3-labelled primers and dUTP. Labelled DNA was then genotyped using DNA microarray hybridization. The current study evaluated the technical efficacy of laboratory-designed HPV DNA microarrays for high-risk HPV genotyping on 57 malignant and non-malignant cervical smears. The approach was evaluated for a broad range of cytological samples: high-grade squamous intraepithelial lesions (HSIL), low-grade squamous intraepithelial lesions (LSIL) and atypical squamous cells of high-grade (ASC-H). High-risk HPV was also detected in six atypical squamous cells of undetermined significance (ASC-US) samples; among them only one cervical specimen was found uninfected, associated with no histological lesion. The HPV oligonucleotide DNA microarray genotyping detected 36 infections with a single high-risk HPV type and 5 multiple infections with several high-risk types. Taken together, these results demonstrate the sensitivity and specificity of the HPV DNA microarray approach. This approach could improve clinical management of patients with cervical cytological abnormalities.
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PMID:Easy and fast detection and genotyping of high-risk human papillomavirus by dedicated DNA microarrays. 1687 79