Accidentally or occupationally exposures to ionizing radiation generally involving the partial-body exposures and this may pose significant health hazards that are indicated by chromosome aberration （CA） induction. ...Accidentally or occupationally exposures to ionizing radiation generally involving the partial-body exposures and this may pose significant health hazards that are indicated by chromosome aberration （CA） induction. In this experiment, the quantification of the frequencies of CA was carried out based on cytogenetic analyses of peripheral blood samples obtained from 4 healthy volunteers as a result of simulation of partial-body exposures. The percentages of mixtures of blood samples irradiated in vitro with 2 Gy of gamma rays were 10, 25, 50, 75 and 100.0%. Lymphocytes were cultured and first-division metaphase cells were collected after culture times of 48 h and then harvested with standard procedures. The results showed that frequencies of unstable CA were depended on the percentage/portion of irradiated blood. All frequencies of observed CA was lower than that of calculated from 100% exposed blood, except in one case, indicating a phenomena of＂dilution＂ of unirradiated into irradiated lymphocytes though there could be a bystander effects taken place. The increasing in frequency for 25-100% portions was also comparable with other similar experiments. The quantification of CAs in lymphocytes is an important methodology of dose assessment for partial-body exposure to ionizing radiation, however, the scenario of exposure should be determined.展开更多
The phenomenon of cytogenetic adaptive and cross-adaptive response induced by low dose irradiation and chemical mutagen in mice is described. We found, firstly, that adaptation can be induced by acute low dose Xirradi...The phenomenon of cytogenetic adaptive and cross-adaptive response induced by low dose irradiation and chemical mutagen in mice is described. We found, firstly, that adaptation can be induced by acute low dose Xirradiation (0-100 mGy). Secondly, a cross-adaptation can occur between X-irradiation and mitomycin C (MMC). And finally, mice pre-exposed to chronic low dose rate￣(60)Co-Gamma irradiation (0-226.0 mGy/day) are less susceptible to chromosome aberration induced by subsequent acute higher Xirradiation. Therefore, our data suggest that radioadaptive response depends on dose, dose rate and time interval. Possible mechanisms are also discussed.展开更多
The effects of selected DNA repair inhibitors on the frequency of human cytomegalovirus (HCMV)-induced chromosome aberrations in human peripheral blood lymphocytes (PBLs) were evaluated. Trealment of HCMV-infected PBL...The effects of selected DNA repair inhibitors on the frequency of human cytomegalovirus (HCMV)-induced chromosome aberrations in human peripheral blood lymphocytes (PBLs) were evaluated. Trealment of HCMV-infected PBLs with camptothecin (0.05 to 0.3μg/ml), an inhibitor of topoisomerase I, for 30 hr resulted in a significant (P<0.01) synergistic enhancement of the frequency of HCMV-induced chromosome damage, on the other hand, a significant increase in the frequency of chromosome damage was not noted for infected PBLs treated with either 3-aminobenzamide (3-AB) (3 to 30μg/ml), an inhibitor of poly (ADP-ribose) poiymerase, ur novobiocin 3 to 30 |ig/ml) an inhibitor of topoiso-merase I or excision repair processes for 30 hr. chromatid-type breaks including chromosome exchanges were the predominant type of chromosome aberrations observed in the HCMV-infected cells treated with camptothecin suggesting that HCMV infection is associated with the induction of single-strand DNA breaks. Furthermore, these findings suggest that HCMV infection does rol inflict dircc: DNA damage which is repaired through 3-AB- or novobiocinsensitive pathways.Human cytomegalovirus (HCMV) is a common pathogen which irferfs about 80% of the world's population causing, for the most part, persistent subcliniclil infeclions (Wellcr, 1971). A relatively small percentage of otherwise healthy immunologically competent people experience clinical HCMV disease (Cohen et al., 1985). Generalized HCMV infection, however, is the bane of individuals whose immune system is compromised (Schooley, 1990) Rubin, 1990). Molecular epidemiological studies strongly suggest that HCMV is one of the most frequent cause of congenital infections and that these infections result in a high incidence of birth defects and developmental abnormalities (Alford et al., 1990). Several studies (Nachtigal et al., 1978; Luleci et al., 1980; AbuBakar et al., 1988) have shown that HCMV infectior can result in an increase in the frequency of chromosome aberrations. Since the ability to cause chromosome damage may be significant in the induction of birth defects and possibly in HCMV-induced malignancy, we undertook the present investigation to evaluate the mechanisms by which HCMV may cause chromosome damage. In ths study, the effects of selected DNA repair inhibitors on the frequency of HCMV-induced chromosome aberrations were evaluated. The results indicae that the presence of camptothecin, but nut 3-aminobenzamidc (3-AB) ro novobiocin, results in a concentration-dependent increase in the frequent) of chromosome aberrations in HCMV-infected peripheral blood lymphocytes (PBLs). Accordingly, it is proposed that HCMV-induced chromosome damage in PBLs does not substantially involve DNA repair activities sensitive to inhibition of poly ADP-ribosylation or excision repair processes, but is related to camp of thccin-sersitive DNA repair, conceivably involving the activity of topoisomrrasc I .展开更多
The chromosome and chromatid type aberration can be induced by benzene and the dicentric and ring ones were not observed in vitro experiment but observed in vivo one. In vitro experiment a good linear regression can b...The chromosome and chromatid type aberration can be induced by benzene and the dicentric and ring ones were not observed in vitro experiment but observed in vivo one. In vitro experiment a good linear regression can be given between benzene concentrations and total aberration cells while power regression for radiation dose.The chromosome aberrations induced by benzene combined with radiation in rabbit blood lymphocytes are higher than in bone marrow cells.展开更多
Propoxur is a widely used dithiocarbamate insecticide. In this study, the clastogenic effect of propoxur has been evaluated using chromosomal aberration assay in mouse bone marrow cells. Single i. p. administration of...Propoxur is a widely used dithiocarbamate insecticide. In this study, the clastogenic effect of propoxur has been evaluated using chromosomal aberration assay in mouse bone marrow cells. Single i. p. administration of propoxur, at 25 mg/kg b.wt., a maximum tolerated dose (MTD) and 12 .5mg/kg b.wt (50% of MTD) have significantly induced different types of aberrations after 24 h of treatment. The aberrations were dose and time dependent and reached a maximum after 24 h of exposure. The sresult suggest a genotoxic potential of propoxur.展开更多
AIM: By using comparative genomic hybridization, gain of 3q was found in 45-86% cases of esophageal squamous cell carcinoma (EC-SCC). Chromosome 3q25.3-qter is the minimal common region with several oncogenes found wi...AIM: By using comparative genomic hybridization, gain of 3q was found in 45-86% cases of esophageal squamous cell carcinoma (EC-SCC). Chromosome 3q25.3-qter is the minimal common region with several oncogenes found within this region. However, amplification patterns of these genes in EC-SCC have never been reported. The possible association of copy number changes of these genes with pathologic characteristics is still not clear. METHODS: Real-time quantitative PCR (Q-PCR) was performed to analyze the copy number changes of 13 candidate genes within this region in 60 primary tumors of EC-SCC, and possible association of copy number changes with pathologic characteristics was analyzed by statistics. Immunohistochemistry (IHC) study was also performed on another set of 111 primary tumors of EC-SCC to verify the association between TP63 expression change and lymph node metastasis status. RESULTS: The average copy numbers (±SE) per haploid genome of individual genes in 60 samples were (from centromere to telomere): SSR3: 4.19 (±0.69); CCNL1: 5.24 (±0.67); SMC4L1: 2.01 (±0.16); EVI1: 2.02 (±0.12); hTERC. 5.28 (±0.54); SKIL 2.71 (±0.14); EIF5A2. 1.95 (±0.12); ECT2: 9.18 (±1.68); PIK3CA: 8.13 (±1.17); EIF4G1: 1.07 (±0.05); 557: 3.07 (±0.25); TP63: 2.51 (±0.22); TFRC. 2.42 (±0.19). Four clusters of amplification were found: SSR3 and CCLN1 at 3q25.31; hTERC and SKIL at 3q26.2; ECT2 and PIK3CA at 3q26.31-q26.32; and 55T, TP63 and TFRC at 3q27.3-q29. Patients with lymph node metastasis had significantly lower copy number of TP63 in the primary tumor than those without lymph node metastasis. IHC study on tissue arrays also showed that patients with lymph node metastasis have significantly lower TP63 staining score in the primary tumor than those without lymph node metastasis. CONCLUSION: This study showed that different amplification patterns were seen among different genes within 3q25.3-qter in EC-SCC, and several novel candidate oncogenes (SSR3, SMC4L1, ECT2, and SST) were identified. TP63 is amplified in early stage of EC-SCC carcinogenesis but down-regulated in advanced stage of disease.展开更多
In this study, freeze-dried water extract from the leaves of Myristica fragrans （Houtt.） was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its co...In this study, freeze-dried water extract from the leaves of Myristica fragrans （Houtt.） was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide （CP） （50 mg/kg） were separately dissolved in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions （A. cepa） were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-l-picrylhydrazyl （DPPH） free radicals＇ scavenging power of the extract was tested using butylated hydroxyanisole （BHA） and butylated hydroxytoluene （BHT） as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed cell division, and induced chromosomal aberrations that were insignificantly different from the negative control （P≤0.05）. However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent.展开更多
Objective To determine the in vitro possible clastogenic and cytotoxic activities of Ulva rigida crude extracts （URE）, and identify their antigenotoxic and protective effects on chemotherapeutic agent mitomycine-C ...Objective To determine the in vitro possible clastogenic and cytotoxic activities of Ulva rigida crude extracts （URE）, and identify their antigenotoxic and protective effects on chemotherapeutic agent mitomycine-C （MMC）. Methods Anti-clastogenic and anti-genotoxic activities of Ulva rigida crude extracts （URE） were studied using chromosome aberration （CA）, sister chromatid exchange （SCE）, and micronuclei （MN） tests in human lymphocytes cultured in vitro. Results The chromosome aberration, sister chromatid exchange or micronuclei tests showed that URE at concentrations of 10, 20, and 40 lag/mL had no clastogenic activity in human lymphocyte cell culture. Three doses of URE significantly decreased the number of chromosomal aberrations and the frequencies of SCE and MN when compared with the culture treated with MMC （P〈0.0001）. Conclusion Although URE itself is not a clastogenic or cytotoxic substance, it possesses strong antigenotoxic, anti-clastogenic, and protective effects on MMC in vitro.展开更多
Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no repor...Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no report on the biological properties of curcumin in plant test systems. The root tip cells were treated with sodium azide at 200 and 300 μg/ml for 3 h and curcumin was given at 5, 10 and 20 μg/ml for 16 h, prior to sodium azide treatment. The tips were squashed after colchicine treatment and the cells were analyzed for chromosome aberration and mitotic index. Curcumin induces chromosomal aberration in Allium cepa root tip cells in an insignificant manner, when compared with untreated control. Sodium azide alone induces chromosomal aberrations significantly with increasing concentrations. The total number of aberrations was significantly reduced in root tip cells pretreated with curcumin. The study reveals that curcumin has antimutagenic potential against sodium azide induced chromosomal aberrations in Allium cepa root meristem cells. In addition, it showed mild cytotoxicity by reducing the percentage of mitotic index in all curcumin treated groups, but the mechanism of action remains unknown. The antimutagenic potential of curcumin is effective at 5 μg/ml in Allium cepa root meristem cells.展开更多
Objective： The progression of human cancer is characterized by the accumulation of genetic instability. An increasing number of experimental genetic molecular techniques have been used to detect chromosome aberration...Objective： The progression of human cancer is characterized by the accumulation of genetic instability. An increasing number of experimental genetic molecular techniques have been used to detect chromosome aberrations. Previous studies on chromosome abnormalities often focused on identifying the frequent loci of chromosome alterations, but rarely addressed the issue of interrelationship of chromosomal abnormalities. In the last few years, several mathematical models have been employed to construct models of carcinogenesis, in an attempt to identify the time order and cause-and-effect relationship of chromosome aberrations. The principles and applications of these models are reviewed and compared in this paper. Mathematical modeling of carcinogenesis can contribute to our understanding of the molecular genetics of tumor development, and identification of cancer related genes, thus leading to improved clinical practice of cancer.展开更多
Haynaldia villosa （2n=2X= 14, VV）, a relative of wheat, plays important roles in wheat improvement mainly owing to its disease resistance. Powdery mildew resistance gene Pm21 has been successfully transferred into w...Haynaldia villosa （2n=2X= 14, VV）, a relative of wheat, plays important roles in wheat improvement mainly owing to its disease resistance. Powdery mildew resistance gene Pm21 has been successfully transferred into wheat by Cytogenetic Institute, Nanjing Agricultural University, China, and is widely used in the current wheat breeding programs. In this research, our objective is to further transfer and utilize the beneficial genes such as eye-spot resistance, yellow rust resistance, and gene of the tufted bristles on the glume ridge （a remarkable morphology） mapped on 2V of Haynaldia villosa. A disomic addition line with gametocidal chromosome 3C ofAegilops triuncialis added in Norin-26 was crossed to the wheat-H, villosa disomic substitution 2V（2D） and the hybrid F1 was then self-crossed. Chromosome C-banding, genomic in situ hybridization （GISH）, and meiotic analysis in combination with molecular markers were applied to detect the chromosome variations derived from hybrids Fz and F3. To date, four translocations including one small segmental translocation T6BS·6BL-2VS, two whole arm translocations （preliminarily designed as T3DS·2VL and T2VS.7DL） and one intercalary translocation T2VS·2VL-W-2VL, one deletion Del. 2VS·2VL-, one monotelosomic Mt2VS, and one isochromosome 2VS·2VS line have been developed and characterized. One wheat SSR marker Xwmc25.120 tagging 2VS and one wheat STS marker NAU/STSBCD135-1 （2BL） tagging 2VL were successfully used to confirm the alien chromosome segments involved in the seven lines. The tufted bristles on the glume ridge appeared in lines T2VS-7DL, Mt2VS, 2VS-2VS as well as the parent DS2V（2D）, whereas in T3DS·2VL, this trait did not appear. The gene controlling the tufted bristles was located on 2VS. Gametocidal chromosome 3C ofAegilops triuncialis could successfully induce chromosome 2V structural changes.展开更多
Although metabolic homeostasis disruption,cellular damage,and premature senescence caused by salinity stress are well-documented in the literature,there are few studies investigating cytological changes induced by sal...Although metabolic homeostasis disruption,cellular damage,and premature senescence caused by salinity stress are well-documented in the literature,there are few studies investigating cytological changes induced by salinity stress within the altered metabolic landscape of rice,and this study aims to fill that gap.The cytological characterization of root tips(in terms of mitotic index and chromosomal abnormalities such as stickiness,laggards,fragments,bridges,micronuclei,ring chromosomes,and total mitotic abnormalities)was conducted on 10 experimental rice landraces from coastal Bangladesh,grown under post-imbibitional salinity stress(PISS),while correlating these changes with their metabolic status.The results revealed a strong correlation between salinity-induced cytological changes in root cells(mitotic index and chromosomal abnormalities)and the redox interactome status of all experimental rice landraces.The landraces Kutepatnai,Talmugur,Nonakochi,and Benapol,which exhibited a higher ability to mitigate PISS-induced chromosomal abnormalities and improve mitotic index,also showed lower accumulation of oxidative stress markers(protein carbonylation,lipid peroxidation,prooxidant accumulation,oxidative stress index,reactive oxygen species(ROS)-antioxidative stress index,and efficiency of ROS processing via the Halliwell-Asada pathway)compared with more susceptible landraces(Charobalam,Jotaibalam,Kachra,and Lalmota).These findings underscore the role of redox biology in preventing chromotoxic effects under salinity stress.Hierarchical cluster analysis and principal component analysis,used to determine variations and similarities among the experimental rice landraces based on cytological attributes,redox interactome,and physiological phenotypes,classified the landraces according to their salinity tolerance and sensitivity.This study proposes a novel approach for exploring redox-regulated cytological fingerprints as a tool for identifying salinity-tolerant rice landraces.展开更多
Background:Ethylhexyl triazone(EHT)and diethylhexyl butamido triazone(HEB)both belong to the recently developed class of triazine ultraviolet filters.However,their toxicity profiles remain unclear.Objective:To assess ...Background:Ethylhexyl triazone(EHT)and diethylhexyl butamido triazone(HEB)both belong to the recently developed class of triazine ultraviolet filters.However,their toxicity profiles remain unclear.Objective:To assess the genotoxic and phototoxic effects of EHT and HEB.Methods:The genotoxicity of EHT and HEB was assessed using in vitro bacterial reverse mutation assays,chromosomal aberration assays,and micronucleus assays.Meanwhile,their phototoxicity was evaluated using in vitro 3T3 neutral red uptake(NRU)phototoxicity assays and in vivo skin phototoxicity tests.Results:In the bacterial reverse mutation assay,the number of bacterial colonies was not significantly higher in the EHT and HEB groups than in the solvent control group.Similarly,the chromosomal aberration assay revealed no increase in aberration rates after either EHT or HEB treatment.In the micronucleus assay,the frequency of micronuclei was comparable between the treatment and control groups.Finally,based on the 3T3 NRU phototoxicity assay,both EHT and HEB(photo-irritation factor<2 and mean photo effect value<0.1)were classified as non-phototoxic.The skin phototoxicity test in vivo showed the same results as in vitro.Conclusion:Results from a series of genotoxicity and phototoxicity assays indicate that EHT and HEB possess neither genotoxic nor phototoxic potential.These findings provide experimental evidence supporting the safety of EHT and HEB for topical applications.展开更多
[Objective] To study the long-term ultra-dry storage method and genetic stability of vegetable seeds.[Method] Seeds of Lycopersicum esculentum,Raphanus satuvus and Apium graveolen.were chosen as material.The changes o...[Objective] To study the long-term ultra-dry storage method and genetic stability of vegetable seeds.[Method] Seeds of Lycopersicum esculentum,Raphanus satuvus and Apium graveolen.were chosen as material.The changes of seed vigor,viability and genetic stability after ultra-storage were discussed by studying the seed potentiality,shoot length,germination percentage and the chromosome aberration rate of root tip cells.[Results] Maintaining the low moisture content,different vegetable species had different storage effects of the long-term storage seeds under normal temperature.The Lycopersicum esculentum and Raphanus satuvus seeds were more suitable to ultra-dry storage at normal temperature,and could keep good genetic stability,while the seeds of Apium graveolen had bad performance.[Conclusion] This study established the foundation of studying ultra-dry storage of vegetable seeds.展开更多
Objective\ To validate the use of Allium sativum as a reliable test model for genotoxicity, isoproturon, a substituted phenylalkylurea herbicide, was evaluated on the root meristem cells by this plant system. M...Objective\ To validate the use of Allium sativum as a reliable test model for genotoxicity, isoproturon, a substituted phenylalkylurea herbicide, was evaluated on the root meristem cells by this plant system. Method\ Test concentrations were selected by determining EC50 and root tips were exposed to various concentrations for 6 or 24 hr. EC50 concentration was calculated to be 70.8 ppm for the root growth. In addition to root growth retardation exposure to isoproturon induced morpholoogical changes like discolouration and stiffness of roots. Results\ Exposure to various experimental concentrations of isoproturon (35-280 ppm), including EC50, significantly and dose-dependently inhibited the mitotic index and induced chromosome breaks/mitotic aberrations at 6 or 24 hr. Conclusion\ The frequency of aberrations was found to be decreased in a dose dependant manner at 24 or 48 hr post exposure, however in comparison of control cells the frequency of aberrations was considerably high which indicates genotoxicity potentials of isoproturon. Further, present study also suggests that Allium sativum is a sensitive, efficient, and reliable test system for measuring the genotoxicity potential of environmental chemicals.展开更多
Aim: To pursue whether cytogenetic aberrations correlate with specific spermatological or hormonal abnormalities.Methods: 305 infertile couples were investigated. All male partners were referred to a complete androlog...Aim: To pursue whether cytogenetic aberrations correlate with specific spermatological or hormonal abnormalities.Methods: 305 infertile couples were investigated. All male partners were referred to a complete andrological work-up with physical examination, determination of hormones, HIV testing and semen analysis. Cytogenetic analysis wascarded out in both partners by means of standard techniques using cultured lymphocytes from peripheral blood. Re-suits: Among the 305 couples, 10 men (3.2%) and 10 women (3.2%) showed constitutional chromosomal aber-rations, including reciprocal translocations (n = 7), Robertsonian translocations (n = 3), inversions (n = 3), otherstructural aberrations (n = 4) and sex chromosome aberrations (n = 3). In addition to the impaired sperm count inmost of the patients, a tendency to an increased proportion of spermatozoa with acrosome defect was observed. Con-clusion: Chromosomal aberrations may contribute to the low fertilization and pregnancy rates in the infertile couples.(Asian J Androl 2000 Dec; 2: 293-296)展开更多
The search for fuels to replace petroleum consumption has caused an increase in the production of biofuels worldwide. The ethanol, which comes from sugarcane, is an energy resource with low polluting potential, but it...The search for fuels to replace petroleum consumption has caused an increase in the production of biofuels worldwide. The ethanol, which comes from sugarcane, is an energy resource with low polluting potential, but its production generates other environmental problems. On average, 10 to 15 liters of vinasse are generated while preparing each liter of ethanol. Vinasse is the final by-product of the biomass distillation, mainly for the production of ethanol, from different cultures such as sugarcane. Because excessive quantities of vinasse are produced, alternatives have been required for use, for example as fertilizer, in a process known as fertigation. These excessive amounts of vinasse applied in soils have generated adverse effects on soil properties and to the organisms. This study carried out the toxic, cytotoxic and genotoxic potential of sugarcane vinasse obtained from two different harvests (Samples I and II), using the Allium cepa organism test. A. cepa seeds were exposed to raw vinasse (RV) and diluted in different concentrations: control soil + raw vinasse (SV);vinasse diluted in water at 50% + control soil (V 50%);vinasse diluted in water at 25% + control soil (V 25%);vinasse diluted in water at 12.5% + control soil (V 12.5%). The chemical characterization of vinasse samples showed a low pH and high concentration of potassium. The results demonstrate that the two RV samples tested are toxic, since no seeds germination was observed. The cytotoxic potential was observed in the sample II of SV and V (50%). All groups evaluated in samples I and II, induced chromosomal alterations, statistically significant compared with negative control. An increase in frequency of micronuclei in meristematic cells was observed in the SV (Sample I) and all groups evaluated in samples II. Based on the results it is concluded that the genetic material of the test-system was damaged when exposed to sugarcane vinasse, suggesting that one should be very careful in the use of this waste that has been used sometimes indiscriminately in soils.展开更多
In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, mic...In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, micronucleus rate and chromosome aberration rate of Vicia faba root tip cells. The results showed that the effects of CrO3 concentration on the mitotic indexes were complicated. CrO3 increases the micronucleus rate of Vicia faba root tip cells. It was found that within certain range of CrO3 concentration the micronucleus rate increased systematically with increased concentration of CrO3, but that the micronucleus rate decreased at higher level of CrO3 and that CrO3 also caused various types of chromosome aberration at a rate which increased systematically with increased concentration of CrO3. We concluded that CrO3 has significant mutagenic effect on Vicia faba root tip cells.展开更多
Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now question...Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now questioned by a growing segment of society. Methods Keeping the above fact in mind, we have conducted in the present study the genotoxicity evaluation of oily sludge samples generated from a petroleum refinery and petrochemical industry and ETP sludge from petroleum refinery using DNA damage, chromosomal aberration, p53 protein induction and apoptosis in short term in vitro mammalian Chinese Hamster Ovary cell cultures. Results It is evident from the results that the oily sludge compounds derived from petroleum refinery and petrochemical industry could cause DNA damage, chromosomal aberration, p53 protein accumulation and apoptotic cell death on exposure to oily sludge extracts in the presence of metabolic activation system (S-9 mix), however, ETP sludge extract could not cause significant genotoxicity in comparison to oily sludge extract and negative control. Conclusion The effect may be attributed to polycyclic aromatic hydrocarbons present in the samples as evidenced from GC-MS.展开更多
文摘Accidentally or occupationally exposures to ionizing radiation generally involving the partial-body exposures and this may pose significant health hazards that are indicated by chromosome aberration （CA） induction. In this experiment, the quantification of the frequencies of CA was carried out based on cytogenetic analyses of peripheral blood samples obtained from 4 healthy volunteers as a result of simulation of partial-body exposures. The percentages of mixtures of blood samples irradiated in vitro with 2 Gy of gamma rays were 10, 25, 50, 75 and 100.0%. Lymphocytes were cultured and first-division metaphase cells were collected after culture times of 48 h and then harvested with standard procedures. The results showed that frequencies of unstable CA were depended on the percentage/portion of irradiated blood. All frequencies of observed CA was lower than that of calculated from 100% exposed blood, except in one case, indicating a phenomena of＂dilution＂ of unirradiated into irradiated lymphocytes though there could be a bystander effects taken place. The increasing in frequency for 25-100% portions was also comparable with other similar experiments. The quantification of CAs in lymphocytes is an important methodology of dose assessment for partial-body exposure to ionizing radiation, however, the scenario of exposure should be determined.
文摘The phenomenon of cytogenetic adaptive and cross-adaptive response induced by low dose irradiation and chemical mutagen in mice is described. We found, firstly, that adaptation can be induced by acute low dose Xirradiation (0-100 mGy). Secondly, a cross-adaptation can occur between X-irradiation and mitomycin C (MMC). And finally, mice pre-exposed to chronic low dose rate￣(60)Co-Gamma irradiation (0-226.0 mGy/day) are less susceptible to chromosome aberration induced by subsequent acute higher Xirradiation. Therefore, our data suggest that radioadaptive response depends on dose, dose rate and time interval. Possible mechanisms are also discussed.
文摘The effects of selected DNA repair inhibitors on the frequency of human cytomegalovirus (HCMV)-induced chromosome aberrations in human peripheral blood lymphocytes (PBLs) were evaluated. Trealment of HCMV-infected PBLs with camptothecin (0.05 to 0.3μg/ml), an inhibitor of topoisomerase I, for 30 hr resulted in a significant (P<0.01) synergistic enhancement of the frequency of HCMV-induced chromosome damage, on the other hand, a significant increase in the frequency of chromosome damage was not noted for infected PBLs treated with either 3-aminobenzamide (3-AB) (3 to 30μg/ml), an inhibitor of poly (ADP-ribose) poiymerase, ur novobiocin 3 to 30 |ig/ml) an inhibitor of topoiso-merase I or excision repair processes for 30 hr. chromatid-type breaks including chromosome exchanges were the predominant type of chromosome aberrations observed in the HCMV-infected cells treated with camptothecin suggesting that HCMV infection is associated with the induction of single-strand DNA breaks. Furthermore, these findings suggest that HCMV infection does rol inflict dircc: DNA damage which is repaired through 3-AB- or novobiocinsensitive pathways.Human cytomegalovirus (HCMV) is a common pathogen which irferfs about 80% of the world's population causing, for the most part, persistent subcliniclil infeclions (Wellcr, 1971). A relatively small percentage of otherwise healthy immunologically competent people experience clinical HCMV disease (Cohen et al., 1985). Generalized HCMV infection, however, is the bane of individuals whose immune system is compromised (Schooley, 1990) Rubin, 1990). Molecular epidemiological studies strongly suggest that HCMV is one of the most frequent cause of congenital infections and that these infections result in a high incidence of birth defects and developmental abnormalities (Alford et al., 1990). Several studies (Nachtigal et al., 1978; Luleci et al., 1980; AbuBakar et al., 1988) have shown that HCMV infectior can result in an increase in the frequency of chromosome aberrations. Since the ability to cause chromosome damage may be significant in the induction of birth defects and possibly in HCMV-induced malignancy, we undertook the present investigation to evaluate the mechanisms by which HCMV may cause chromosome damage. In ths study, the effects of selected DNA repair inhibitors on the frequency of HCMV-induced chromosome aberrations were evaluated. The results indicae that the presence of camptothecin, but nut 3-aminobenzamidc (3-AB) ro novobiocin, results in a concentration-dependent increase in the frequent) of chromosome aberrations in HCMV-infected peripheral blood lymphocytes (PBLs). Accordingly, it is proposed that HCMV-induced chromosome damage in PBLs does not substantially involve DNA repair activities sensitive to inhibition of poly ADP-ribosylation or excision repair processes, but is related to camp of thccin-sersitive DNA repair, conceivably involving the activity of topoisomrrasc I .
文摘The chromosome and chromatid type aberration can be induced by benzene and the dicentric and ring ones were not observed in vitro experiment but observed in vivo one. In vitro experiment a good linear regression can be given between benzene concentrations and total aberration cells while power regression for radiation dose.The chromosome aberrations induced by benzene combined with radiation in rabbit blood lymphocytes are higher than in bone marrow cells.
文摘Propoxur is a widely used dithiocarbamate insecticide. In this study, the clastogenic effect of propoxur has been evaluated using chromosomal aberration assay in mouse bone marrow cells. Single i. p. administration of propoxur, at 25 mg/kg b.wt., a maximum tolerated dose (MTD) and 12 .5mg/kg b.wt (50% of MTD) have significantly induced different types of aberrations after 24 h of treatment. The aberrations were dose and time dependent and reached a maximum after 24 h of exposure. The sresult suggest a genotoxic potential of propoxur.
基金Supported by the National Natural Science Foundation of China (30170394) the Special Fund for Promotion of Education Ministry of Science P.R.C (985) and "973"Foundation of China (001cb51010201).
基金Supported by the National Microarray and Gene Expression Analysis Core Facility of the National Research Program for Genomic Medicine at National Yang-Ming University (http://www.ym.edu. tw/microarray),annual project Grant From National Science Council (Grant NO. NSC 92-2314-B-075-055), Taiwan, China
文摘AIM: By using comparative genomic hybridization, gain of 3q was found in 45-86% cases of esophageal squamous cell carcinoma (EC-SCC). Chromosome 3q25.3-qter is the minimal common region with several oncogenes found within this region. However, amplification patterns of these genes in EC-SCC have never been reported. The possible association of copy number changes of these genes with pathologic characteristics is still not clear. METHODS: Real-time quantitative PCR (Q-PCR) was performed to analyze the copy number changes of 13 candidate genes within this region in 60 primary tumors of EC-SCC, and possible association of copy number changes with pathologic characteristics was analyzed by statistics. Immunohistochemistry (IHC) study was also performed on another set of 111 primary tumors of EC-SCC to verify the association between TP63 expression change and lymph node metastasis status. RESULTS: The average copy numbers (±SE) per haploid genome of individual genes in 60 samples were (from centromere to telomere): SSR3: 4.19 (±0.69); CCNL1: 5.24 (±0.67); SMC4L1: 2.01 (±0.16); EVI1: 2.02 (±0.12); hTERC. 5.28 (±0.54); SKIL 2.71 (±0.14); EIF5A2. 1.95 (±0.12); ECT2: 9.18 (±1.68); PIK3CA: 8.13 (±1.17); EIF4G1: 1.07 (±0.05); 557: 3.07 (±0.25); TP63: 2.51 (±0.22); TFRC. 2.42 (±0.19). Four clusters of amplification were found: SSR3 and CCLN1 at 3q25.31; hTERC and SKIL at 3q26.2; ECT2 and PIK3CA at 3q26.31-q26.32; and 55T, TP63 and TFRC at 3q27.3-q29. Patients with lymph node metastasis had significantly lower copy number of TP63 in the primary tumor than those without lymph node metastasis. IHC study on tissue arrays also showed that patients with lymph node metastasis have significantly lower TP63 staining score in the primary tumor than those without lymph node metastasis. CONCLUSION: This study showed that different amplification patterns were seen among different genes within 3q25.3-qter in EC-SCC, and several novel candidate oncogenes (SSR3, SMC4L1, ECT2, and SST) were identified. TP63 is amplified in early stage of EC-SCC carcinogenesis but down-regulated in advanced stage of disease.
文摘In this study, freeze-dried water extract from the leaves of Myristica fragrans （Houtt.） was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide （CP） （50 mg/kg） were separately dissolved in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions （A. cepa） were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-l-picrylhydrazyl （DPPH） free radicals＇ scavenging power of the extract was tested using butylated hydroxyanisole （BHA） and butylated hydroxytoluene （BHT） as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed cell division, and induced chromosomal aberrations that were insignificantly different from the negative control （P≤0.05）. However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent.
基金supported by a grant from the Scientific and Technical Research Council of Turkey, Ankara (TüBiTAK, 107T279 (TBAG/HD-304).
文摘Objective To determine the in vitro possible clastogenic and cytotoxic activities of Ulva rigida crude extracts （URE）, and identify their antigenotoxic and protective effects on chemotherapeutic agent mitomycine-C （MMC）. Methods Anti-clastogenic and anti-genotoxic activities of Ulva rigida crude extracts （URE） were studied using chromosome aberration （CA）, sister chromatid exchange （SCE）, and micronuclei （MN） tests in human lymphocytes cultured in vitro. Results The chromosome aberration, sister chromatid exchange or micronuclei tests showed that URE at concentrations of 10, 20, and 40 lag/mL had no clastogenic activity in human lymphocyte cell culture. Three doses of URE significantly decreased the number of chromosomal aberrations and the frequencies of SCE and MN when compared with the culture treated with MMC （P〈0.0001）. Conclusion Although URE itself is not a clastogenic or cytotoxic substance, it possesses strong antigenotoxic, anti-clastogenic, and protective effects on MMC in vitro.
基金Project (No. SP/SO/HS-21/2002) supported by the Department of Science and Technology, Government of India, New Delhi
文摘Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no report on the biological properties of curcumin in plant test systems. The root tip cells were treated with sodium azide at 200 and 300 μg/ml for 3 h and curcumin was given at 5, 10 and 20 μg/ml for 16 h, prior to sodium azide treatment. The tips were squashed after colchicine treatment and the cells were analyzed for chromosome aberration and mitotic index. Curcumin induces chromosomal aberration in Allium cepa root tip cells in an insignificant manner, when compared with untreated control. Sodium azide alone induces chromosomal aberrations significantly with increasing concentrations. The total number of aberrations was significantly reduced in root tip cells pretreated with curcumin. The study reveals that curcumin has antimutagenic potential against sodium azide induced chromosomal aberrations in Allium cepa root meristem cells. In addition, it showed mild cytotoxicity by reducing the percentage of mitotic index in all curcumin treated groups, but the mechanism of action remains unknown. The antimutagenic potential of curcumin is effective at 5 μg/ml in Allium cepa root meristem cells.
基金supported by a grant from the Education Department of Zhejiang Province (No.Y200803235)
文摘Objective： The progression of human cancer is characterized by the accumulation of genetic instability. An increasing number of experimental genetic molecular techniques have been used to detect chromosome aberrations. Previous studies on chromosome abnormalities often focused on identifying the frequent loci of chromosome alterations, but rarely addressed the issue of interrelationship of chromosomal abnormalities. In the last few years, several mathematical models have been employed to construct models of carcinogenesis, in an attempt to identify the time order and cause-and-effect relationship of chromosome aberrations. The principles and applications of these models are reviewed and compared in this paper. Mathematical modeling of carcinogenesis can contribute to our understanding of the molecular genetics of tumor development, and identification of cancer related genes, thus leading to improved clinical practice of cancer.
基金the National Natural Science Foundation of China （30270827）.
文摘Haynaldia villosa （2n=2X= 14, VV）, a relative of wheat, plays important roles in wheat improvement mainly owing to its disease resistance. Powdery mildew resistance gene Pm21 has been successfully transferred into wheat by Cytogenetic Institute, Nanjing Agricultural University, China, and is widely used in the current wheat breeding programs. In this research, our objective is to further transfer and utilize the beneficial genes such as eye-spot resistance, yellow rust resistance, and gene of the tufted bristles on the glume ridge （a remarkable morphology） mapped on 2V of Haynaldia villosa. A disomic addition line with gametocidal chromosome 3C ofAegilops triuncialis added in Norin-26 was crossed to the wheat-H, villosa disomic substitution 2V（2D） and the hybrid F1 was then self-crossed. Chromosome C-banding, genomic in situ hybridization （GISH）, and meiotic analysis in combination with molecular markers were applied to detect the chromosome variations derived from hybrids Fz and F3. To date, four translocations including one small segmental translocation T6BS·6BL-2VS, two whole arm translocations （preliminarily designed as T3DS·2VL and T2VS.7DL） and one intercalary translocation T2VS·2VL-W-2VL, one deletion Del. 2VS·2VL-, one monotelosomic Mt2VS, and one isochromosome 2VS·2VS line have been developed and characterized. One wheat SSR marker Xwmc25.120 tagging 2VS and one wheat STS marker NAU/STSBCD135-1 （2BL） tagging 2VL were successfully used to confirm the alien chromosome segments involved in the seven lines. The tufted bristles on the glume ridge appeared in lines T2VS-7DL, Mt2VS, 2VS-2VS as well as the parent DS2V（2D）, whereas in T3DS·2VL, this trait did not appear. The gene controlling the tufted bristles was located on 2VS. Gametocidal chromosome 3C ofAegilops triuncialis could successfully induce chromosome 2V structural changes.
文摘Although metabolic homeostasis disruption,cellular damage,and premature senescence caused by salinity stress are well-documented in the literature,there are few studies investigating cytological changes induced by salinity stress within the altered metabolic landscape of rice,and this study aims to fill that gap.The cytological characterization of root tips(in terms of mitotic index and chromosomal abnormalities such as stickiness,laggards,fragments,bridges,micronuclei,ring chromosomes,and total mitotic abnormalities)was conducted on 10 experimental rice landraces from coastal Bangladesh,grown under post-imbibitional salinity stress(PISS),while correlating these changes with their metabolic status.The results revealed a strong correlation between salinity-induced cytological changes in root cells(mitotic index and chromosomal abnormalities)and the redox interactome status of all experimental rice landraces.The landraces Kutepatnai,Talmugur,Nonakochi,and Benapol,which exhibited a higher ability to mitigate PISS-induced chromosomal abnormalities and improve mitotic index,also showed lower accumulation of oxidative stress markers(protein carbonylation,lipid peroxidation,prooxidant accumulation,oxidative stress index,reactive oxygen species(ROS)-antioxidative stress index,and efficiency of ROS processing via the Halliwell-Asada pathway)compared with more susceptible landraces(Charobalam,Jotaibalam,Kachra,and Lalmota).These findings underscore the role of redox biology in preventing chromotoxic effects under salinity stress.Hierarchical cluster analysis and principal component analysis,used to determine variations and similarities among the experimental rice landraces based on cytological attributes,redox interactome,and physiological phenotypes,classified the landraces according to their salinity tolerance and sensitivity.This study proposes a novel approach for exploring redox-regulated cytological fingerprints as a tool for identifying salinity-tolerant rice landraces.
基金supported by the National Natural Science Foundation of China(No.81600459)National Natural Science Foundation of Hubei Province(No.2016CFB312)+3 种基金Talent Introduction Project of Hubei Polytechnic University(No.15xjz03R)Industry-University Collaboration(No.KY2023-269)Hubei Key Laboratory of Kidney Disease Pathogenesis and Intervention Foundation(No.SB202103)Provincial College Student Innovation and Entrepreneurship Training Program(No.S202210920011).
文摘Background:Ethylhexyl triazone(EHT)and diethylhexyl butamido triazone(HEB)both belong to the recently developed class of triazine ultraviolet filters.However,their toxicity profiles remain unclear.Objective:To assess the genotoxic and phototoxic effects of EHT and HEB.Methods:The genotoxicity of EHT and HEB was assessed using in vitro bacterial reverse mutation assays,chromosomal aberration assays,and micronucleus assays.Meanwhile,their phototoxicity was evaluated using in vitro 3T3 neutral red uptake(NRU)phototoxicity assays and in vivo skin phototoxicity tests.Results:In the bacterial reverse mutation assay,the number of bacterial colonies was not significantly higher in the EHT and HEB groups than in the solvent control group.Similarly,the chromosomal aberration assay revealed no increase in aberration rates after either EHT or HEB treatment.In the micronucleus assay,the frequency of micronuclei was comparable between the treatment and control groups.Finally,based on the 3T3 NRU phototoxicity assay,both EHT and HEB(photo-irritation factor<2 and mean photo effect value<0.1)were classified as non-phototoxic.The skin phototoxicity test in vivo showed the same results as in vitro.Conclusion:Results from a series of genotoxicity and phototoxicity assays indicate that EHT and HEB possess neither genotoxic nor phototoxic potential.These findings provide experimental evidence supporting the safety of EHT and HEB for topical applications.
基金Supported by Beijing Nova Program (2008B37)Beijing Municipal Scientific Research Foundation for the Returned Overseas ChineseScholars (20080006)~~
文摘[Objective] To study the long-term ultra-dry storage method and genetic stability of vegetable seeds.[Method] Seeds of Lycopersicum esculentum,Raphanus satuvus and Apium graveolen.were chosen as material.The changes of seed vigor,viability and genetic stability after ultra-storage were discussed by studying the seed potentiality,shoot length,germination percentage and the chromosome aberration rate of root tip cells.[Results] Maintaining the low moisture content,different vegetable species had different storage effects of the long-term storage seeds under normal temperature.The Lycopersicum esculentum and Raphanus satuvus seeds were more suitable to ultra-dry storage at normal temperature,and could keep good genetic stability,while the seeds of Apium graveolen had bad performance.[Conclusion] This study established the foundation of studying ultra-dry storage of vegetable seeds.
文摘Objective\ To validate the use of Allium sativum as a reliable test model for genotoxicity, isoproturon, a substituted phenylalkylurea herbicide, was evaluated on the root meristem cells by this plant system. Method\ Test concentrations were selected by determining EC50 and root tips were exposed to various concentrations for 6 or 24 hr. EC50 concentration was calculated to be 70.8 ppm for the root growth. In addition to root growth retardation exposure to isoproturon induced morpholoogical changes like discolouration and stiffness of roots. Results\ Exposure to various experimental concentrations of isoproturon (35-280 ppm), including EC50, significantly and dose-dependently inhibited the mitotic index and induced chromosome breaks/mitotic aberrations at 6 or 24 hr. Conclusion\ The frequency of aberrations was found to be decreased in a dose dependant manner at 24 or 48 hr post exposure, however in comparison of control cells the frequency of aberrations was considerably high which indicates genotoxicity potentials of isoproturon. Further, present study also suggests that Allium sativum is a sensitive, efficient, and reliable test system for measuring the genotoxicity potential of environmental chemicals.
文摘Aim: To pursue whether cytogenetic aberrations correlate with specific spermatological or hormonal abnormalities.Methods: 305 infertile couples were investigated. All male partners were referred to a complete andrological work-up with physical examination, determination of hormones, HIV testing and semen analysis. Cytogenetic analysis wascarded out in both partners by means of standard techniques using cultured lymphocytes from peripheral blood. Re-suits: Among the 305 couples, 10 men (3.2%) and 10 women (3.2%) showed constitutional chromosomal aber-rations, including reciprocal translocations (n = 7), Robertsonian translocations (n = 3), inversions (n = 3), otherstructural aberrations (n = 4) and sex chromosome aberrations (n = 3). In addition to the impaired sperm count inmost of the patients, a tendency to an increased proportion of spermatozoa with acrosome defect was observed. Con-clusion: Chromosomal aberrations may contribute to the low fertilization and pregnancy rates in the infertile couples.(Asian J Androl 2000 Dec; 2: 293-296)
文摘The search for fuels to replace petroleum consumption has caused an increase in the production of biofuels worldwide. The ethanol, which comes from sugarcane, is an energy resource with low polluting potential, but its production generates other environmental problems. On average, 10 to 15 liters of vinasse are generated while preparing each liter of ethanol. Vinasse is the final by-product of the biomass distillation, mainly for the production of ethanol, from different cultures such as sugarcane. Because excessive quantities of vinasse are produced, alternatives have been required for use, for example as fertilizer, in a process known as fertigation. These excessive amounts of vinasse applied in soils have generated adverse effects on soil properties and to the organisms. This study carried out the toxic, cytotoxic and genotoxic potential of sugarcane vinasse obtained from two different harvests (Samples I and II), using the Allium cepa organism test. A. cepa seeds were exposed to raw vinasse (RV) and diluted in different concentrations: control soil + raw vinasse (SV);vinasse diluted in water at 50% + control soil (V 50%);vinasse diluted in water at 25% + control soil (V 25%);vinasse diluted in water at 12.5% + control soil (V 12.5%). The chemical characterization of vinasse samples showed a low pH and high concentration of potassium. The results demonstrate that the two RV samples tested are toxic, since no seeds germination was observed. The cytotoxic potential was observed in the sample II of SV and V (50%). All groups evaluated in samples I and II, induced chromosomal alterations, statistically significant compared with negative control. An increase in frequency of micronuclei in meristematic cells was observed in the SV (Sample I) and all groups evaluated in samples II. Based on the results it is concluded that the genetic material of the test-system was damaged when exposed to sugarcane vinasse, suggesting that one should be very careful in the use of this waste that has been used sometimes indiscriminately in soils.
文摘In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, micronucleus rate and chromosome aberration rate of Vicia faba root tip cells. The results showed that the effects of CrO3 concentration on the mitotic indexes were complicated. CrO3 increases the micronucleus rate of Vicia faba root tip cells. It was found that within certain range of CrO3 concentration the micronucleus rate increased systematically with increased concentration of CrO3, but that the micronucleus rate decreased at higher level of CrO3 and that CrO3 also caused various types of chromosome aberration at a rate which increased systematically with increased concentration of CrO3. We concluded that CrO3 has significant mutagenic effect on Vicia faba root tip cells.
文摘Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now questioned by a growing segment of society. Methods Keeping the above fact in mind, we have conducted in the present study the genotoxicity evaluation of oily sludge samples generated from a petroleum refinery and petrochemical industry and ETP sludge from petroleum refinery using DNA damage, chromosomal aberration, p53 protein induction and apoptosis in short term in vitro mammalian Chinese Hamster Ovary cell cultures. Results It is evident from the results that the oily sludge compounds derived from petroleum refinery and petrochemical industry could cause DNA damage, chromosomal aberration, p53 protein accumulation and apoptotic cell death on exposure to oily sludge extracts in the presence of metabolic activation system (S-9 mix), however, ETP sludge extract could not cause significant genotoxicity in comparison to oily sludge extract and negative control. Conclusion The effect may be attributed to polycyclic aromatic hydrocarbons present in the samples as evidenced from GC-MS.
