Acrylonitrile ; toxicity ; Carcinogens ; toxicity ; Humans ; Mutagens ; toxicity ; Occupational Exposure

Benzene ; poisoning ; DNA Damage ; DNA Repair ; genetics ; Deoxyguanosine ; analogs & derivatives ; genetics ; Humans ; Mutagens ; poisoning ; Poisoning ; genetics

Xeroderma pigmentosum is autosomal recessive, degenerative disease generated by abnormal repair of DNA damaged by ultraviolet radiation and environmental mutagens. DeSanctis-Cacchione syndrome is the most severe form of xeroderma pigmentosum variant. This syndrome is characterized with microcephaly, progressive mental retardation and deterioration, retarded growth and sexual development, sensorineural deafness, and cerebellar ataxia, choreoathetsis, quadriparesis. We describe the case of a 17 year old female patient, which fits into Desanctis-Cacchione syndrome clinically.
Adolescent ; Cerebellar Ataxia ; Deafness ; DNA ; Female ; Humans ; Intellectual Disability ; Microcephaly ; Mutagens ; Quadriplegia ; Sexual Development ; Xeroderma Pigmentosum

BACKGROUND: Fanconi's anemia (FA) is an autosomal recessive disease characterized by aplastic anemia, pre-malignancy, congenital malformations and chromosome breakage syndromes. As up to 30% of patients have no detectable congenital anomalies, the modern diagnosis of FA rests on chromosomal breakage of patient's cells induced by chemical clastogens such as diepoxybutane (DEB) or mitomycin-C (MMC). METHODS: We have done chromosome breakage test to differentiate FA from 11 aplastic anemia, three Diamond-Blackfan syndrome, three myelodysplastic syndrome, one acute leukemia with congenital anomaly and three siblings of FA. The peripheral blood lymphocytes from each individual were co-cultured in phytohemagglutinin-containing medium by the three methods, i.e., DEB treated, MMC treated and un-treated. RESULTS: Five cases were found to have increased chromosomal breakages to DEB and MMC, confirming diagnosis of FA. Other 21 cases showed no increased chromosomal breakages. No overlap was found between FA group and others (P<0.01). In one FA, there was no increased spontaneous breakage, but increased breakage to DEB and MMC. Of five FA, one case showed no congenital anomalies. CONCLUSIONS: Chromosme breakage test was shown to be simple, reliable and useful in ascertaining the diagnosis of FA.
Anemia, Aplastic ; Chromosome Breakage* ; Diagnosis* ; Fanconi Anemia* ; Humans ; Leukemia ; Lymphocytes ; Mitomycin ; Mutagens ; Myelodysplastic Syndromes ; Siblings

INTRODUCTION: Chromosomal mutations are casual events in neoplasia development. Biomarker cytogenetic assays can determine exposure to mutagenic agents in occupational settings. This study assessed early biological marker chromosomal aberrations among health workers in the chemotheraphy oncology wards/ clinics, exploring its association to the subjects' occupational, environmental and baseline profile.
METHODS: This was an IRB approved cross-sectional exploratory study among hospital personnel working in the chemotherapy oncology facility of a tertiary government hospital, who underwent structured interview and blood extraction for cytogenetic assay after informed consent. Study funds only permitted assay of 44 specimens of 144 planned sample size, hence, Stata 6.0 only analyzed data from 44 subjects.
RESULTS: All 44 subjects had varying exposure to chemotherapy drug infusions. Of these, 79% had 1.0 breaks per cell (hypersensitive). Predominantly chromatid breaks (CTB), chromatid gaps (CTG), sister chromatid exhanges (SCE) were seen. No significant association was shown between mutagenic sensitivity and baseline characteristics, but with small sample size.
CONCLUSION: 21% borderline to hypersensitive mutagenic sensitivity among oncology workers at the tertiary government hospital is relatively significant, despite small sample size, connoting a must preventive promotive practice of chemotherapy administration in the workplace.

Human ; Male ; Female ; Chromosome Aberrations ; Chromosomes ; Drug Therapy ; Personnel, Hospital ; Cytogenetics ; Chromatids ; Mutagens

Sister chromatid exchange (SCE) has recently become a common cytogenic assay system for detecting exposure to chemical mutagens and carcinogens. One application of SCE is the monitoring of populations believed to have been exposed to such agents. A cross-sectional study of SCE frequency in peripheral blood lymphocytes from 45 Koreans aged 61 to 84 years was conducted. The effect of cigarette smoking and age on SCE was assessed by different degrees of smoking status such as smokers (n = 14), ex-smokers (n = 16) and non-smokers (n = 15). Mean spontaneous SCE per cell for the smokers (11.5 +/- 1.1) was significantly higher (p < 0.05) than that for the non-smokers (8.8 +/- 0.3). However, mean SCE frequencies per cell for the ex-smokers (10.3 +/- 0.6) were not significantly different from those of the smokers or the non-smokers. The smokers showed an increased number of high SCE frequency cells (HFCs) when compared to the ex-smokers and non-smokers (p < 0.05). The mean SCE frequencies of the non-smokers showed a statistically significant increase (p < 0.05) with the subject's age. These results show that age and smoking habits contribute a great deal in setting a higher degree of basal DNA damage in elderly Koreans, and smoking appeared to be a more significant damaging factor than age.
Aged* ; Carcinogens ; Cross-Sectional Studies ; DNA Damage* ; DNA* ; Humans* ; Lymphocytes* ; Mutagens ; Sister Chromatid Exchange ; Smoke* ; Smoking*

In the screening of marine mangrove derived fungi for lovastatin productivity, endophytic Aspergillus luchuensis MERV10 exhibited the highest lovastatin productivity (9.5 mg/gds) in solid state fermentation (SSF) using rice bran. Aspergillus luchuensis MERV10 was used as the parental strain in which to induce genetic variabilities after application of different mixtures as well as doses of mutagens followed by three successive rounds of genome shuffling. Four potent mutants, UN6, UN28, NE11, and NE23, with lovastatin productivity equal to 2.0-, 2.11-, 1.95-, and 2.11-fold higher than the parental strain, respectively, were applied for three rounds of genome shuffling as the initial mutants. Four hereditarily stable recombinants (F3/3, F3/7, F3/9, and F3/13) were obtained with lovastatin productivity equal to 50.8, 57.0, 49.7, and 51.0 mg/gds, respectively. Recombinant strain F3/7 yielded 57.0 mg/gds of lovastatin, which is 6-fold and 2.85-fold higher, respectively, than the initial parental strain and the highest mutants UN28 and NE23. It was therefore selected for the optimization of lovastatin production through improvement of SSF parameters. Lovastatin productivity was increased 32-fold through strain improvement methods, including mutations and three successive rounds of genome shuffling followed by optimizing SSF factors.
Aspergillus* ; Efficiency ; Fermentation* ; Fungi ; Genome* ; Humans ; Lovastatin* ; Mass Screening ; Mutagens ; Parents

OBJECTIVETo explore a flow cytometry (FCM)-based method for discriminating aneugen- or clastogen-induced micronuclei.

METHODSCells were stained with anti-CD71-FITC and PI, and the PI fluorescent signal intensity of micronucleated reticulocyte (MN-RET) in the peripheral blood of NIH mouse treated with COL or CP was detected by flow cytometry.

RESULTSThe ratio of the median of the intensity of MN-RET fluorescent signals to that of nucleated cell was low in the cyclophosphamide treated mouse, while the median was high in the colchicine treated mouse.

CONCLUSIONThe flow cytometry-based micronucleus assay can be used to discriminate primarily smaller MN induced by the clastogen exposure from the larger MN induced by an aneugen.

Animals ; Colchicine ; toxicity ; Cyclophosphamide ; toxicity ; Flow Cytometry ; methods ; Male ; Mice ; Micronuclei, Chromosome-Defective ; Mutagens ; toxicity ; Reticulocytes ; drug effects ; ultrastructure

OBJECTIVEThe aim of this study was to investigate the use of the lesion-specific endonucleases-modified comet assay for analysis of DNA oxidation in cell lines.

METHODSDNA breaks and oxidative damage were evaluated by normal alkaline and formamidopyrimidine-DNA-glycosylase (FPG) modified comet assays. Cytotoxicity were assessed by MTT method. The human bronchial epithelial cell (16HBE) were treated with benzo (a) pyrene (B(a)P), methyl methanesulfonate (MMS), colchicine (COL) and vincristine (VCR) respectively, and the dose is 20 µmol/L, 25 mg/ml, 5 mg/L and 0.5 mg/L for 24 h, respectively. Oxidative damage was also detected by levels of reactive oxygen species in treated cells.

RESULTSFour genotoxicants give higher cytotoxicity and no significant changes on parameters of comet assay treated by enzyme buffer. Cell survival rate were (59.69 ± 2.60) %, (54.33 ± 2.81) %, (53.11 ± 4.00) %, (51.43 ± 3.92) % in four groups, respectively. There was the direct DNA damage induced by test genotoxicants presented by tail length, Olive tail moment (TM) and tail DNA (%) in the comet assay. The presence of FPG in the assays increased DNA migration in treated groups when compared to those without it, and the difference was statistically significant which indicated that the clastogen and aneugen could induce oxidative damage in DNA strand. In the three parameters, the Olive TM was changed most obviously after genotoxicants treatment. In the contrast group, the Olive TM of B(a) P,MMS, COL,VCR in the contrast groups were 22.99 ± 17.33, 31.65 ± 18.86, 19.86 ± 9.56 and 17.02 ± 9.39, respectively, after dealing with the FPG, the Olive TM were 34.50 ± 17.29, 43.80 ± 10.06, 33.10 ± 12.38, 28.60 ± 10.53, increased by 58.94%, 38.48%, 66.86% and 68.21%, respectively (t value was 3.91, 3.89, 6.66 and 3.87, respectively, and all P < 0.05), and the correlation between Olive TM and reactive oxygen species was better than other parameters (r = 0.77, P < 0.05).

CONCLUSIONThis study indicates that FPG-comet assay appears more specific for detecting oxidative DNA damage induced by genotoxicants exposure, and the application of comet assay will be expanded. The endonuclease modified comet assay will be used widely in the toxicology and molecular epidemiology study.

Cell Line ; Comet Assay ; methods ; DNA Damage ; Endonucleases ; Humans ; Mutagens ; toxicity ; Oxidation-Reduction ; Oxidative Stress ; Reactive Oxygen Species ; metabolism

Animals ; DNA Replication ; DNA-Directed DNA Polymerase ; genetics ; Expressed Sequence Tags ; Gene Expression ; Humans ; Mutagens ; toxicity ; Mutation ; genetics ; Signal Transduction