In a previous study of the potential mutagenic action of isoflurane using the sister chromatid exchange (SCE) test in lymphocytes of surgical patients, it appeared that SCE increased in a group of 11 cigarette smokers, there being no effect in patients who were non-smokers. In the present study, 63 cigarette smokers were examined by the SCE test before and after minor orthopaedic operations und...

In yeast, anaphase entry depends on Pds1 proteolysis, while chromosome re-duplication in the subsequent S-phase involves degradation of mitotic cyclins such as Clb2. Sequential proteolysis of Pds1 and mitotic cyclins is mediated by the anaphase-promoting complex (APC). Lagging chromosomes or spindle damage are detected by surveillance mechanisms (checkpoints) which block anaphase onset, cytokin...

AIM To evaluate the genetic instability of 11 fertile and 25 infertile men. METHODS The methodology of sister chromatid exchanges (SCEs) was applied to cultures of peripheral blood lymphocytes, and the levels of SCEss were analyzed as a quantitative index of genotoxicity, along with the values of the mitotic index (MI) and the proliferation rate index (PRI) as qualitative indices of cytotoxic...

Although induction of sister chromatid exchanges (SCEs) following nitrosourea exposure may be greater during cell proliferation, the increase could be offset by the action of the DNA repair protein O6-alkylguanine DNA alkyltransferase (alkyltransferase). To evaluate these factors in resting and proliferating (phytohemagglutinin stimulated) human lymphocytes, we studied the effect of changes in ...

The distribution of alkylated deoxynucleosides and bases has been determined in the DNA of a sensitive and a resistant human gliomaderived cell line exposed to therapeutic levels of |'"l1|.Y-(2-chloroethyl)/V-nitrosourea in vitro. The resistant cell line is 5-fold less sensitive to the cytotoxic effects of yV-(2-chloroethyl)-Ar-nitrosourea and 8-fold less sensitive to sister chromatid exchange ...

The aim of the present study was to investigate DNA damage in peripheral blood lymphocytes of breast cancer (BC) patients before and after administration of chemotherapy. We analyzed the frequency of sister chromatid exchange (SCE), occurrence of micronuclei (MN), and lymphocyte proliferation rate index (PRI) as cytogenetic markers in 28 female BC patients before and after chemotherapy, and in ...

Chromosome aberrations (CAs) and sister chromatid exchanges (SCEs) frequencies were estimated in peripheral lymphocytes from 21 radiology technicians, and from 21 non-exposed control subjects. We exclusively considered individuals who neither smoke nor consume drugs or alcohol for a period of at least two years prior to the analysis. Significant differences were found between exposed and contro...

A case of trisomy 9p syndrome is reported. The karyotype showed a tandem duplication of the short arm and of the inverted heterochromatic block of chromosome 9. Unequal sister chromatid exchange seems to be the only possible cause of this finding.

BACKGROUND The analysis of sister chromatid exchange (SCE) is a cytogenetic technique used to show DNA damage due to an exchange of DNA fragments between sister chromatids. OBJECTIVE To determine whether HLA-B27 positive patients with ankylosing spondylitis (AS) were associated with higher SCE frequencies than patients without B27. METHODS Lymphocytes from 38 patients with AS (15 women, 23 ...

Meiosis entails sorting and separating both homologous and sister chromatids. The mechanisms for connecting sister chromatids and homologs during meiosis are highly conserved and include specialized forms of the cohesin complex and a tightly regulated homolog synapsis/recombination pathway designed to yield regular crossovers between homologous chromatids. Drosophila male meiosis is of special ...