Objective To assess the effect of benzene on sperm DNA damage ;Methods Twenty-seven benzene-exposed workers were selected as exposed group and 35 normal sperm donors as control group. Air concentration of benzene seri...Objective To assess the effect of benzene on sperm DNA damage ;Methods Twenty-seven benzene-exposed workers were selected as exposed group and 35 normal sperm donors as control group. Air concentration of benzene series in workshop was determined by gas chromatography. As an internal exposure dose of benzene, the concentration of trans, trans-muconic acid （ttMA） was determined by high performance liquid chromatography. DNA was detected by modified single cell gel electrophoresis （SCGE）. Results The air concentrations of benzene, toluene and xylene at the workplace were 86.49±2.83 mg/m^3, 97.20±3.52 mg/m^3 and 97.45± 2.10 mg/m^3, respectively. Urinary ttMA in exposed group （1.040 ± 0.617 mg/L） was significantly higher than that of control group （0.819 ± 0.157 mg/L）. The percentage of head DNA, determined by modified SCGE method, significantly decreased in the exposed group （n=13, 70.18% ± 7.36%） compared with the control （n=16, 90.62% ± 2.94%）（P〈0.001）. Conclusion The modified SCGE method can be used to investigate the damage of sperm DNA. As genotoxin and reprotoxins, benzene had direct effect on the germ cells during the spermatogenesiss.展开更多
Objective:To evaluate retrospectively the effect of general anesthesia on DNA damage in the blood mononuclear cells(PBMCs) of surgical patients in order to provide evidence for a better nursing care during the procedu...Objective:To evaluate retrospectively the effect of general anesthesia on DNA damage in the blood mononuclear cells(PBMCs) of surgical patients in order to provide evidence for a better nursing care during the procedure.Methods:Clinical charts of 76 patients who underwent operation under general anesthesia and 76 healthy control subjects with documented results of DNA damage extent in PBMCs from the single-cell gel electrophoresis(SCGE) or cornel assay and scrum contents of superoxide dismutase(SOD) and malondialdehyde(MDA) from biochemical analyses were reviewed.The percentage of comet PBMCs and tail DNA and semm contents of SOD and MAD were analyzed by student t-test.Results:Compared with health) control subjects, generally anesthetized surgical patients had significantly higher%comet PBMCs and%tail DNA(P【0.05) and significantly lower serum concentrations of SOD(P【0.05) and significantly higher serum concentrations of MAD(P【0.05).Compared with levels before general anesthesia in surgical patients,%comet PBMCs,%tail DNA.and serum lexels of MAD were significantly higher(P【0.05 or 0.01).and semm levels of SOD were significantly lower(P【0.05).alter general anesthesia.Conclusions:General anesthesia during surgery causes a certain degree of hypoxia and PBMC damage.Particular attention should be paid to monitoring and maintenance of blood oxygen saturation in patients undergoing surgery under general anesthesia.展开更多
DNA damage is one of the most important consequences of oxidative stress in the cells. If DNA repair is unable to modify these inducible DNA damages, genomic instability may lead to mutation, cancer, aging and many ot...DNA damage is one of the most important consequences of oxidative stress in the cells. If DNA repair is unable to modify these inducible DNA damages, genomic instability may lead to mutation, cancer, aging and many other diseases. Single cell gel electrophoresis or comet assay is a common and versatile method to quantify these types of DNA damages. DNA damages induced by hydrogen peroxide(H_2O_2) are one of the proper models for measurement of protective ability of different compounds. So the main aim of this review is to provide an overview about protection ability of medicinal plants and their potential mechanism against H_2O_2 induced DNA damages. In this review, relevant researches on the effect of medicinal plants on DNA damages induced by H_2O_2 and possible molecular mechanisms are discussed.It seems that, medicinal plants are considered as therapeutic key factors to protect DNA from consequences caused by oxidative stress. Sufficient in vitro evidences introduce them as DNA protective agents through different mechanisms including antioxidant activity and some other cellular mechanisms. Moreover, in order to correlate the antigenotoxicity effects with their potential antioxidant property, most of medicinal plants were evaluated in term of antioxidant activity using standard methods. This review highlights the preventive effects of herbal medicine against oxidative DNA damages as well as provides rational possibility to engage them in animal studies and future clinical investigations.展开更多
The effects of heavy metals Cd^(2+),Pb^(2+)and Zn^(2+)at 0.05,0.5 and 5.0 mg/L level and their interactions at 0.5 mg/L level on DNA damage in hepatopancreas of loach Misgurnus anguillicaudatus for 1-35 days exposure ...The effects of heavy metals Cd^(2+),Pb^(2+)and Zn^(2+)at 0.05,0.5 and 5.0 mg/L level and their interactions at 0.5 mg/L level on DNA damage in hepatopancreas of loach Misgurnus anguillicaudatus for 1-35 days exposure were examined by single cell gel electrophoresis(SCGE).For each test group,20 loaches with similar body size(5.17-7.99 g;11.79-13.21 cm)were selected and kept in aquaria with dechlori-nated water at(22±1)℃and fed a commercial diet every 48 h.According to the percentage of damaged DNA with tail and its TL/D(tail length to diameter of nucleus)value,the relationship between DNA damage degree and heavy metal dose and exposure time was determined.Results showed that the percentage of damaged DNA and the TL/D value were increased with the prolonged exposure time.The highest percentage(84.85%)of damaged DNA was shown in 5.0 mg/L Zn^(2+)group after 28 days exposure and the biggest TL/D value(2.50)in all treated groups after 35 days exposure.During the first treated week,the damnification of DNA was mainly recognized as the first level,after that time,the third damaged level was mostly observed and the percentage of damaged DNA was beyond 80%.The joint toxic effects among Cd^(2+),Pb^(2+)or Zn^(2+)revealed much complexity,but it generally displayed that the presence of Cd^(2+)could enhance the genotoxicity of Pb^(2+)or Zn^(2+).In conclusion,the results suggestedthattherewasasignificanttime-anddose-depended relationship between the heavy metal and DNA damage in hepatopancreas of loach,and SCGE could represent a useful means to evaluate the genotoxicity of environmental contamination on aquatic organisms.展开更多
In this study, we sought to elucidate the process of DNA degradation in brain and dental pulp cells of mice, within postmortem 0-72 hours, by using the single cell gel electrophoresis assay and professional comet imag...In this study, we sought to elucidate the process of DNA degradation in brain and dental pulp cells of mice, within postmortem 0-72 hours, by using the single cell gel electrophoresis assay and professional comet image analysis and processing techniques. The frequency of comet-like cells, the percentage of tail DNA, tail length, tail moment, Olive moment and tail area increased in tandem with increasing postmortem interval. In contrast, the head radius, the percentage of head DNA and head area showed a decreasing trend. Linear regression analysis revealed a high correlation between these parameters and the postmortem interval. The findings suggest that the single cell gel electrophoresis assay is a quick and sensitive method to detect DNA degradation in brain and dental pulp cells, providing an objective and accurate new way to estimate postmortem interval.展开更多
文摘Objective To assess the effect of benzene on sperm DNA damage ;Methods Twenty-seven benzene-exposed workers were selected as exposed group and 35 normal sperm donors as control group. Air concentration of benzene series in workshop was determined by gas chromatography. As an internal exposure dose of benzene, the concentration of trans, trans-muconic acid （ttMA） was determined by high performance liquid chromatography. DNA was detected by modified single cell gel electrophoresis （SCGE）. Results The air concentrations of benzene, toluene and xylene at the workplace were 86.49±2.83 mg/m^3, 97.20±3.52 mg/m^3 and 97.45± 2.10 mg/m^3, respectively. Urinary ttMA in exposed group （1.040 ± 0.617 mg/L） was significantly higher than that of control group （0.819 ± 0.157 mg/L）. The percentage of head DNA, determined by modified SCGE method, significantly decreased in the exposed group （n=13, 70.18% ± 7.36%） compared with the control （n=16, 90.62% ± 2.94%）（P〈0.001）. Conclusion The modified SCGE method can be used to investigate the damage of sperm DNA. As genotoxin and reprotoxins, benzene had direct effect on the germ cells during the spermatogenesiss.
文摘Objective:To evaluate retrospectively the effect of general anesthesia on DNA damage in the blood mononuclear cells(PBMCs) of surgical patients in order to provide evidence for a better nursing care during the procedure.Methods:Clinical charts of 76 patients who underwent operation under general anesthesia and 76 healthy control subjects with documented results of DNA damage extent in PBMCs from the single-cell gel electrophoresis(SCGE) or cornel assay and scrum contents of superoxide dismutase(SOD) and malondialdehyde(MDA) from biochemical analyses were reviewed.The percentage of comet PBMCs and tail DNA and semm contents of SOD and MAD were analyzed by student t-test.Results:Compared with health) control subjects, generally anesthetized surgical patients had significantly higher%comet PBMCs and%tail DNA(P【0.05) and significantly lower serum concentrations of SOD(P【0.05) and significantly higher serum concentrations of MAD(P【0.05).Compared with levels before general anesthesia in surgical patients,%comet PBMCs,%tail DNA.and serum lexels of MAD were significantly higher(P【0.05 or 0.01).and semm levels of SOD were significantly lower(P【0.05).alter general anesthesia.Conclusions:General anesthesia during surgery causes a certain degree of hypoxia and PBMC damage.Particular attention should be paid to monitoring and maintenance of blood oxygen saturation in patients undergoing surgery under general anesthesia.
文摘DNA damage is one of the most important consequences of oxidative stress in the cells. If DNA repair is unable to modify these inducible DNA damages, genomic instability may lead to mutation, cancer, aging and many other diseases. Single cell gel electrophoresis or comet assay is a common and versatile method to quantify these types of DNA damages. DNA damages induced by hydrogen peroxide(H_2O_2) are one of the proper models for measurement of protective ability of different compounds. So the main aim of this review is to provide an overview about protection ability of medicinal plants and their potential mechanism against H_2O_2 induced DNA damages. In this review, relevant researches on the effect of medicinal plants on DNA damages induced by H_2O_2 and possible molecular mechanisms are discussed.It seems that, medicinal plants are considered as therapeutic key factors to protect DNA from consequences caused by oxidative stress. Sufficient in vitro evidences introduce them as DNA protective agents through different mechanisms including antioxidant activity and some other cellular mechanisms. Moreover, in order to correlate the antigenotoxicity effects with their potential antioxidant property, most of medicinal plants were evaluated in term of antioxidant activity using standard methods. This review highlights the preventive effects of herbal medicine against oxidative DNA damages as well as provides rational possibility to engage them in animal studies and future clinical investigations.
基金This work was supported by the Key Project of Chinese Ministry of Education(02080)the Open Fund of State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,The Chinese Academy of Science(2002FB08).
文摘The effects of heavy metals Cd^(2+),Pb^(2+)and Zn^(2+)at 0.05,0.5 and 5.0 mg/L level and their interactions at 0.5 mg/L level on DNA damage in hepatopancreas of loach Misgurnus anguillicaudatus for 1-35 days exposure were examined by single cell gel electrophoresis(SCGE).For each test group,20 loaches with similar body size(5.17-7.99 g;11.79-13.21 cm)were selected and kept in aquaria with dechlori-nated water at(22±1)℃and fed a commercial diet every 48 h.According to the percentage of damaged DNA with tail and its TL/D(tail length to diameter of nucleus)value,the relationship between DNA damage degree and heavy metal dose and exposure time was determined.Results showed that the percentage of damaged DNA and the TL/D value were increased with the prolonged exposure time.The highest percentage(84.85%)of damaged DNA was shown in 5.0 mg/L Zn^(2+)group after 28 days exposure and the biggest TL/D value(2.50)in all treated groups after 35 days exposure.During the first treated week,the damnification of DNA was mainly recognized as the first level,after that time,the third damaged level was mostly observed and the percentage of damaged DNA was beyond 80%.The joint toxic effects among Cd^(2+),Pb^(2+)or Zn^(2+)revealed much complexity,but it generally displayed that the presence of Cd^(2+)could enhance the genotoxicity of Pb^(2+)or Zn^(2+).In conclusion,the results suggestedthattherewasasignificanttime-anddose-depended relationship between the heavy metal and DNA damage in hepatopancreas of loach,and SCGE could represent a useful means to evaluate the genotoxicity of environmental contamination on aquatic organisms.
基金supported by Key Research Plan of the Ministry of Public Security of China, No. 2011ZDYJXJXY005Scientific Research Foundation of the Higher Education Institutions of Liaoning Province, China, No. 2008Z205
文摘In this study, we sought to elucidate the process of DNA degradation in brain and dental pulp cells of mice, within postmortem 0-72 hours, by using the single cell gel electrophoresis assay and professional comet image analysis and processing techniques. The frequency of comet-like cells, the percentage of tail DNA, tail length, tail moment, Olive moment and tail area increased in tandem with increasing postmortem interval. In contrast, the head radius, the percentage of head DNA and head area showed a decreasing trend. Linear regression analysis revealed a high correlation between these parameters and the postmortem interval. The findings suggest that the single cell gel electrophoresis assay is a quick and sensitive method to detect DNA degradation in brain and dental pulp cells, providing an objective and accurate new way to estimate postmortem interval.
