In this work, the DNA-damaging effect of hydrogen peroxide on the structural integrity of nucleolar organizer regions (NORs) was studied for the first time by comet-FISH in the Pacific oyster Crassostrea gigas. Global DNA damage was assessed in hemocytes using an alkaline version of the comet assay. Next, NOR sensitivity was analyzed by mapping major rDNA repeat unit by fluorescence in situ hyb...

background: lymphocytes of fanconi anemia (fa) show an increased sensitivity to the alkylating agents such as mitomycin c (mmc), but their responses to gamma-irradiation is controversial. the extent of dna damage in leukocytes of fa patients following irradiation and mmc treatment was studied at cellular and single chromosome level. methods: dna damage induced by gamma-rays and mmc was measured...

This study was undertaken to evaluate the compatibility of Giemsa staining protocol with the comet assay. We showed, for the first time, that DNA comets can be visualized and analyzed using Giemsa staining. We generated DNA damage dose response curves for human peripheral blood lymphocytes exposed to X-ray radiation using the comet assay with either SybrGreen I or Giemsa stain. The dose respons...

OBJECTIVE A previous study by our research group evaluated the levels of DNA damage using the comet assay in hemodialysis patients with type 2 diabetes mellitus. The same blood samples were also evaluated using the cytochalasin B micronucleus assay. A comparison of the results of the two assays is presented here. METHODS Whole blood samples were collected from 22 type 2 diabetes mellitus pati...

background: this study has used biomarker of exposure-effect continuum to examine the biological characteristics of organophosphate (op) toxicity and its genotoxic effect among rice farmers.   materials and methods : a cross-sectional study was conducted among 160 pesticide exposed rice farmers and 160 adults from the fishing village as the unexposed group. they share the common socio-economica...

Casearia sylvestris is used in Brazil as a popular medicine to treat ulcer, inflammation and tumour. Caseargrewiin F is a clerodane diterpene isolated from the ethanolic leaf extract of C.sylvestris. The aim of the study was to assess the capacity of the ethanolic extract of C.sylvestris leaves and caseargrewiin F to protect DNA and verify if both the compounds cause some DNA damage, using the ...

The comet assay is considered to be a rapid and sensitive procedure for quantitating DNA damage in mammalian cells. In this article, to interpret its outcomes adequately, its power to detect low level genotoxicity and factors affecting its power were reviewed. Although the development of initial lesions into alkali-labile sites and/or SSBs through repairing events is an important factor to supp...

DNA fragmentation is considered an important parameter of semen quality, and of significant value as a predictor of male fertility. Poor quality chromatin is closely associated with, and highly indicative of, some fertility problems. Many methodologies to assess DNA fragmentation in spermatozoa are available, but they are all unable to differentiate between single-stranded DNA breaks (SSB) and ...

This note is about three interesting 15th and 16th century sightings of comets in Kashmiri chronicles. We provide reasons for their identification as the 1468 S1, 1531 (Halley’s), and 1533 M1 comets.