Background: Most of the cytogenetic dosimetry, except Premature Chromosome Condensation assay, saturates at 6 Gy. Present studies are aimed to assess feasibility of simple CB-MN assay for prescreening of high dose accidental exposures. Materials and Methods: Human peripheral blood lymphocytes from two donors were gamma irradiated to different doses ranging from 0-15Gy, cultured for 72 h. Cytoch...

Following infection of E. coli B with ligase-deficient rII bacteriophage T4D recombination between linked markers is increased 4.2 fold and heterozygote frequency increased 2.3 fold. In such infection recombination occurs at a rapid rate for an extended period. This is in contrast to the time course of recombination observed in wild-type, lysis-inhibited, or lysis-defective (gene t defective) i...

Recombination is the main cause of genetic diversity. Thus, errors in this process can lead to chromosomal abnormalities. Recombination events are confined to narrow chromosome regions called hotspots in which characteristic DNA motifs are found. Genomic analyses have shown that both recombination hotspots and DNA motifs are distributed unevenly along human chromosomes and are much more frequen...

The notion that targeted drugs can unplug gain-of-function tumor pathways has revitalized pharmaceutical research, but the survival benefits of this strategy have so far proven modest. A weakness of oncogene-blocking approaches is that they do not address the problem of cancer progression as selected by the recessive phenotypes of genetic instability and apoptotic resistance which in turn arise...

Background/Aim: Epidemiological studies showed an increased risk of developing laryngeal head and neck squamous cell carcinoma (HNSCC) for employees working in the construction business. This suggested a causal link between exposure to cement particles development HNSCC but data were missing. Materials Methods: We established Organisation Economic Co-operation Development (OECD) guideline 487-c...

BACKGROUND An estimated 800,000 people worldwide are occupationally exposed to welding-fumes. Previous studies show that the exposure to such fumes is associated with damage to genetic material and increased cancer risk. In this study, we evaluate the genotoxic effect of welding-fumes using the Micronucleus Test on oral mucosa cells of Mexican welders. MATERIAL AND METHODS We conducted a cros...

As part of a larger effort to provide proof-of-concept in vitro-only risk assessments, we have developed a suite of high-throughput assays for key readouts in the p53 DNA damage response toxicity pathway: double-strand break DNA damage (p-H2AX), permanent chromosomal damage (micronuclei), p53 activation, p53 transcriptional activity, and cell fate (cell cycle arrest, apoptosis, micronuclei). Do...

This study investigated the role of DNA double strand breaks and DNA base damage in radiation-induced bystander responses in Chinese hamster ovary (CHO) cell lines. Two CHO repair-deficient clones, xrs5 (DNA double strand break repair-deficient) and EM9 (DNA base excision repair-deficient) were used in addition to the wild type (CHO). The Gray Cancer Institute ultrasoft X-ray microprobe is a po...

Bystander effects have been observed repeatedly in mammalian cells following photon and alpha particle irradiation. However, few studies have been performed to investigate bystander effects arising from neutron irradiation. Here we asked whether neutrons also induce a bystander effect in two normal human lymphoblastoid cell lines. These cells were exposed to fast neutrons produced by targeting ...

The aim of the present study was to establish the extent of in vitro radioresponse of lymphocytes among 62 healthy adults of both genders and to estimate the distribution of baseline micronuclei and radiosensitivity among individuals of the study population using the cytochalasin block micronucleus test. A younger study group consisted of 10 males (mean age, 22.4 years; range, 21-27) and 12 fem...