AIM: To study the oxidative DNA damage to adolescents of hepatocellular carcinoma (HCC) families in Guangxi Zhuang Autonomous Region, China.METHODS: Peripheral leukocytes' DNA 7, 8-dihydro-8-oxoguanine (8-oxoG) an...AIM: To study the oxidative DNA damage to adolescents of hepatocellular carcinoma (HCC) families in Guangxi Zhuang Autonomous Region, China.METHODS: Peripheral leukocytes' DNA 7, 8-dihydro-8-oxoguanine (8-oxoG) and repair enzyme hOGG1 were quantified by flow-cytometry. hOGG1-Cys326Ser single nucleotide polymorphism (SNP) was distinguished by polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) assay.RESULTS: There was a positive correlation between 8-oxoG and repair enzyme hOGG1 expression (P＜0.001). HCC children (n=21) in Fusui county had a higher level of hOGG1(P＜0.01) and a lower level of 8-oxoG (P＜0.05) than the controls (n=63) in Nanning city. Children in Nanning exposed to passive-smoking had a higher hOGG1 expression (P＜0.05)than the non-exposers. 8-oxoG and hOGG1 were negatively correlated with body mass index, while hOGG1 was positively correlated with age. There was a peak of 8-oxoG level nearby the 12 year point. Individuals with the hOGG1 326Ser allele had a significantly marginal higher concentration of leukocyte 8-oxoG level than hOGG1 326Cys allele.CONCLUSION: This is the first report using flow-cytometry to simultaneously quantify both the DNA oxidative damage and its repairing enzyme hOGG1. The results provide new insights towards a better understanding of the mechanisms of oxidative stress in a population highly susceptible to hepatocarcinogenesis.展开更多
Aim: To explore the barriers faced by general practitioners (GPs) in the management of patients with erectile dysfunction (ED). Methods: This was a qualitative analysis of focus group discussions and in-depth inter vi...Aim: To explore the barriers faced by general practitioners (GPs) in the management of patients with erectile dysfunction (ED). Methods: This was a qualitative analysis of focus group discussions and in-depth inter views involving 28 Malaysian GPs. Results: GPs' perception of ED being not a serious condition was a major determinant of their prescribing practice. Doctor's age (younger), gender (female), short consultation time and lack of experience were cited as barriers. The GPs' prescribing habits were heavily influenced by the feedback from the first few patients under treatment, the uncertainty of etiology of ED without proper assessment and the profit margin with bulk purchase. Other barriers include Patients' coexisting medical conditions, older age, lower socio-economic status, unrealistic expectations and inappropriate use of the anti-impoteneet drugs. Cardiovascular side effects and cost were two most important drug barriers. Conclusion: The factors influencing the management of ED among the general practitioners were multiple and complex. An adequate understanding of how these factors (doctors, patients and drugs) interact can assist in the formulation and implementation of strategies that encourage GPs to identify and manage ED patients.展开更多
To investigate the potential anti-tumor effects and its relative its relative mechanism of active component in chrysanthemum,on human nasopharyngeal carcinoma(NPC).Parthenolide(PN) was used as tested substance and exp...To investigate the potential anti-tumor effects and its relative its relative mechanism of active component in chrysanthemum,on human nasopharyngeal carcinoma(NPC).Parthenolide(PN) was used as tested substance and exposed to NPC cell lines,CNE1 and CNE2.Cell toxicity indexes and cyclooxygenase-2(COX-2) expression were determined.Results showed that in CNE1 cells,with high level COX-2,there were significant cytotoxicities after PN-treated.However,there were not inducible effects on CNE2 cells with low level COX-2.It was indicated that PN could induce cytotoxicity in NPC cell,which correlated with its intracellular COX-2 expression.展开更多
Objective To explore the protective effects of N Acetylcysteine (NAC) on exogenous hydrogen peroxide and endogenous superoxide anion induced DNA strand breakage in human spermatozoa by using the single cell gel el...Objective To explore the protective effects of N Acetylcysteine (NAC) on exogenous hydrogen peroxide and endogenous superoxide anion induced DNA strand breakage in human spermatozoa by using the single cell gel electropherosis (SCGE) Methods Sperm cells were exposed to 0.5 mmol/L of H 2O 2 or 5.0 mmol/L of β NADPH with or without 0.1, 0.5, 1.0 mmol/L of NAC. The percentage of sperm comet cells and the comet tail lengths were measured in the treated sperm cells by using SCGE. Results Both percentage of comet sperm nuclei and mean tail length in sperm cells exposed to 0.5 mmol/L hydrogen peroxide with different concentrations of NAC decrease significantly in a dose dependent manner as compared with sperm cells exposed to H 2O 2 without NAC or catalase. Although mean tail length in sperm cells exposed to 5.0 mmol/L of β NADPH with different concentrations of NAC decreases significantly compared with sperm cells exposed to β NADPH without NAC or SOD, there were no significant differences on the percentage of sperm comet cells between sperm cells exposed to 5.0 mmol/L of β NADPH with different concentrations of NAC and sperm cells exposed to 5.0 mmol/L of β NADPH without NAC. Conclusion NAC has a protective effect on exogenous hydrogen peroxide induced DNA damage, while protective effect of NAC against O - 2 induced DNA strand breakage is significant but very weak.展开更多
基金the Guangxi Natural Sciences Grant,No.GKZ9912028 and No.GKJ0236030Guangxi Educational Committee Grant,No.GZBH 2000-272+1 种基金Guangxi Health Ministry Medicine Grant,No.Z2001087Singapore Science Grant,No.R-186-000-044-213
文摘AIM: To study the oxidative DNA damage to adolescents of hepatocellular carcinoma (HCC) families in Guangxi Zhuang Autonomous Region, China.METHODS: Peripheral leukocytes' DNA 7, 8-dihydro-8-oxoguanine (8-oxoG) and repair enzyme hOGG1 were quantified by flow-cytometry. hOGG1-Cys326Ser single nucleotide polymorphism (SNP) was distinguished by polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) assay.RESULTS: There was a positive correlation between 8-oxoG and repair enzyme hOGG1 expression (P＜0.001). HCC children (n=21) in Fusui county had a higher level of hOGG1(P＜0.01) and a lower level of 8-oxoG (P＜0.05) than the controls (n=63) in Nanning city. Children in Nanning exposed to passive-smoking had a higher hOGG1 expression (P＜0.05)than the non-exposers. 8-oxoG and hOGG1 were negatively correlated with body mass index, while hOGG1 was positively correlated with age. There was a peak of 8-oxoG level nearby the 12 year point. Individuals with the hOGG1 326Ser allele had a significantly marginal higher concentration of leukocyte 8-oxoG level than hOGG1 326Cys allele.CONCLUSION: This is the first report using flow-cytometry to simultaneously quantify both the DNA oxidative damage and its repairing enzyme hOGG1. The results provide new insights towards a better understanding of the mechanisms of oxidative stress in a population highly susceptible to hepatocarcinogenesis.
文摘Aim: To explore the barriers faced by general practitioners (GPs) in the management of patients with erectile dysfunction (ED). Methods: This was a qualitative analysis of focus group discussions and in-depth inter views involving 28 Malaysian GPs. Results: GPs' perception of ED being not a serious condition was a major determinant of their prescribing practice. Doctor's age (younger), gender (female), short consultation time and lack of experience were cited as barriers. The GPs' prescribing habits were heavily influenced by the feedback from the first few patients under treatment, the uncertainty of etiology of ED without proper assessment and the profit margin with bulk purchase. Other barriers include Patients' coexisting medical conditions, older age, lower socio-economic status, unrealistic expectations and inappropriate use of the anti-impoteneet drugs. Cardiovascular side effects and cost were two most important drug barriers. Conclusion: The factors influencing the management of ED among the general practitioners were multiple and complex. An adequate understanding of how these factors (doctors, patients and drugs) interact can assist in the formulation and implementation of strategies that encourage GPs to identify and manage ED patients.
文摘To investigate the potential anti-tumor effects and its relative its relative mechanism of active component in chrysanthemum,on human nasopharyngeal carcinoma(NPC).Parthenolide(PN) was used as tested substance and exposed to NPC cell lines,CNE1 and CNE2.Cell toxicity indexes and cyclooxygenase-2(COX-2) expression were determined.Results showed that in CNE1 cells,with high level COX-2,there were significant cytotoxicities after PN-treated.However,there were not inducible effects on CNE2 cells with low level COX-2.It was indicated that PN could induce cytotoxicity in NPC cell,which correlated with its intracellular COX-2 expression.
基金China Medical Board ( 980 0 1 ) and Natural Science Foundation ofAnhui Province( 99j1 0 0 95)
文摘Objective To explore the protective effects of N Acetylcysteine (NAC) on exogenous hydrogen peroxide and endogenous superoxide anion induced DNA strand breakage in human spermatozoa by using the single cell gel electropherosis (SCGE) Methods Sperm cells were exposed to 0.5 mmol/L of H 2O 2 or 5.0 mmol/L of β NADPH with or without 0.1, 0.5, 1.0 mmol/L of NAC. The percentage of sperm comet cells and the comet tail lengths were measured in the treated sperm cells by using SCGE. Results Both percentage of comet sperm nuclei and mean tail length in sperm cells exposed to 0.5 mmol/L hydrogen peroxide with different concentrations of NAC decrease significantly in a dose dependent manner as compared with sperm cells exposed to H 2O 2 without NAC or catalase. Although mean tail length in sperm cells exposed to 5.0 mmol/L of β NADPH with different concentrations of NAC decreases significantly compared with sperm cells exposed to β NADPH without NAC or SOD, there were no significant differences on the percentage of sperm comet cells between sperm cells exposed to 5.0 mmol/L of β NADPH with different concentrations of NAC and sperm cells exposed to 5.0 mmol/L of β NADPH without NAC. Conclusion NAC has a protective effect on exogenous hydrogen peroxide induced DNA damage, while protective effect of NAC against O - 2 induced DNA strand breakage is significant but very weak.
