Objective To detect the oxidative DNA damage in diabetic patients and to investigate the relationship of oxidative DNA damage with diabetes and diabetic nephropathy. Methods Single cell gel electrophoresis （SCGE） wa...Objective To detect the oxidative DNA damage in diabetic patients and to investigate the relationship of oxidative DNA damage with diabetes and diabetic nephropathy. Methods Single cell gel electrophoresis （SCGE） was used to detect the DNA strand breaks in peripheral blood lymphocytes, and oxidative DNA damage product and serum 8-OHdG were determined by a competitive ELISA in 47 cases, including 25 patients without diabetic complications, 22 patients with diabetic nephropathy and 25 normal control subjects. Results Diabetic patients showed greater oxidative damage to DNA. The percentage of comet cells and the length of DNA migration （comet tail length） of peripheral blood lymphocytes were significantly increased in patients with diabetes, and significantly higher in patients with diabetic nephropathy than in diabetic patients without vascular complications （P〈0.05）. There was a significant increase in serum 8-OHdG in diabetic patients compared with normal subjects （P〈0.05）. Moreover, serum 8-OHdG was much higher in patients with diabetic nephropathy than in diabetic patients without vascular complications （P〈0.05）. Coneluslon There is severe oxidative DNA damage in diabetic patients. Enhanced oxidative stress may be associated with diabetes, especially in patients with diabetic nephropathy.展开更多
Among the different DNA anomalies that can be present in the male gamete, DNA fragmentation is the most frequent, particularly in infertile subjects. There is now consistent evidence that a sperm containing fragmented...Among the different DNA anomalies that can be present in the male gamete, DNA fragmentation is the most frequent, particularly in infertile subjects. There is now consistent evidence that a sperm containing fragmented DNA can be alive, motile, morphologically normal and able to fertilize an oocyte. There is also evidence that the oocyte is able to repair DNA damage; however, the extent of this repair depends on the type of DNA damage present in the sperm, as well as on the quality of the oocyte. Thus, it is important to understand the possible consequences of sperm DNA fragmentation （SDF） for embryo development, implantation, pregnancy outcome and the health of progeny conceived, both naturally and by assisted reproductive technology （ART）. At present, data on the consequences of SDF for reproduction are scarce and, in many ways, inconsistent. The differences in study conclusions might result from the different methods used to detect SDF, the study design and the inclusion criteria. Consequently, it is difficult to decide whether SDF testing should be carried out in fertility assessment and ART. It is clear that there is an urgent need for the standardisation of the methods and for additional clinical studies on the impact of SDF on ART outcomes.展开更多
Aims: Anaemia is a common comorbidity in chronic heart failure(CHF). The predictors of new onset anaemia(NOA) and its long-term prognostic value, particularly in patients treated with beta-blockers, are not known. Met...Aims: Anaemia is a common comorbidity in chronic heart failure(CHF). The predictors of new onset anaemia(NOA) and its long-term prognostic value, particularly in patients treated with beta-blockers, are not known. Methods and results: In COMET, 3029 patients with CHF in NYHA Ⅱ-IV and EF< 35%were randomized to carvedilol or metoprolol tartrate and were followed for an average of 58 months. Plasma haemoglobin(Hb) concentrations were measured at a central laboratory at randomization, at four monthly intervals for the first year and annually thereafter. According to WHO criteria, anaemia was defined when Hb measured< 13 g/dL for men and< 12 g/dL for women. We considered anaemia to be severe when Hb< 11.5 g/dL for men and< 10.5 g/dL for women. The baseline mean Hb was 14.2±1.5 g/dL(n=2996) and 15.9%of patients had anaemia(males, 16.0%; females, 15.2%). At baseline, severe anaemia was found in 3.3%of patients(males, 3.6%; females, 2.0%). During the study, all-cause mortality(RR 1.47) death or hospitalization(RR 1.28), and heart failure hospitalization(RR 1.43, all P< 0.0001) were higher in anaemic when compared with non-anaemic patients. In patients without anaemia at baseline, at the end of the study, the cumulative frequency of NOA was 28.1%in males and 27.0%in females. NOA increased over time from 14.2%at year 1 to 27.5%at year 5. Predictors of NOA were: higher age, diuretic dose, creatinine(all P< 0.0001), higher serum potassium, lower serum sodium, body mass index, and use of aldosterone antagonists, carvedilol, and digitalis(all P< 0.03). Treatment with carvedilol(vs. metoprolol tartrate) was associated with a 24%increased risk to develop NOA(P=0.0047),but not severe anaemia(P=0.18). Patients with a Hb decrease of >3 g/dL(RR 3.37, P< 0.0001) or of 2.0-3.0 g/dL(RR 1.47, P=0.011) from baseline had an increased subsequent mortality when compared with patients having Hb increases of 0-1.0 g/dL. Conclusion: In stable ambulatory CHF patients, development of NOA is frequent and can be predicted by a set of clinical v展开更多
针对C/S(Client/Server)架构下的OPC(OLE for Process Control)实时监控系统在互联网应用中的局限,采用ASP.NET和Comet技术,提出了一种B/S(Browser/Server)架构下OPC实时监控系统的设计和实现。该方案只需在客户端安装支持Ajax技术的浏...针对C/S(Client/Server)架构下的OPC(OLE for Process Control)实时监控系统在互联网应用中的局限,采用ASP.NET和Comet技术,提出了一种B/S(Browser/Server)架构下OPC实时监控系统的设计和实现。该方案只需在客户端安装支持Ajax技术的浏览器即可正常工作,通过与采用其他技术实现此系统的方案的对比研究,发现该方案具有较好的易用性、跨平台性。对OPC-DA(OPC-Data Access)连接组件进行了改进和封装,使其更加符合实际应用的需要。模拟实验结果表明,采用Comet技术的方案在保证较好的实时性的同时,服务器的开销也较小,是一种满足Web应用实时性需求的可行方案。展开更多
Objective To determine the interaction between 2450-MHz microwaves (MW) radiation and mitomycin C (MMC). Methods The synergistic genotoxic effects of low-intensity 2450-MHz microwave and MMC on human lymphocytes were ...Objective To determine the interaction between 2450-MHz microwaves (MW) radiation and mitomycin C (MMC). Methods The synergistic genotoxic effects of low-intensity 2450-MHz microwave and MMC on human lymphocytes were studied using single cell gel electrophoresis (SCGE) assay (comet assay) and cytokinesis-blocked micronucleus (CBMN) test in vitro. The whole blood cells from a male donor and a female donor were either only exposed to 2450-MHz microwaves (5.0 mW/cm2) for 2 h or only exposed to MMC (0.0125 μ/mL, 0.025 μg/mL, 0.05μg/mL and 0.1 μg/mL) for 24 h; and the samples were exposed to MMC for 24 h after exposure to MW for 2 h. Results In the comet assay, the comet lengths ( 29.1 μm and 25.9 μm) of MW were not significantly longer than those (26.3 μrn and 24.1 μm) of controls (P>0.05). The comet lengths (57.4 μm, 68.9 μm, 91.4 μm, 150.6μm and 50.6 μm, 71.7μm, 100.1 μm, 145.1 μm) of 4 MMC groups were significantly longer than those of controls (P<0.01). The comet lengths (59.1 μm, 92.3 μm, 124.5 μm, 182.7 μm and 57.4 μm, 85.5 μm, 137.5 μm, 178.3 μm) of 4 MW plus MMC groups were significantly longer than those of controls too (P<0.01). The comet lengths of MW plus MMC groups were significantly longer than those of the corresponding MMC doses (P<0.05 or P<0.01) when the doses of MMC were ≥50.025 μg/mL. In the CBMN, the micronucleated cell (MNC) rates of MW were 5% and 6%, which showed no difference compared with those (4‰ and 4‰) of controls (P>0.05). The MNC rates of 4 MMC groups were 8‰, 9‰, 14‰, 23‰ and 8‰, 8‰, 16‰, 30‰ respectively. When the doses of MMC were 3≥0.05 μg/mL, MNC rates of MMC were higher than those of controls (P<0.05). MNC rates of 4 MW plus MMC groups were 12‰, 13‰, 20‰, 32‰ and 8‰, 9‰, 23‰, 40‰. When the doses of MMC were 5≥0.05 μg/mL, MNC rates of MW plus MMC groups were much higher than those of controls (P<0.01). MNC rates of 4 MW plus MMC groups were not significantly higher than those of the corresponding MMC doses. Concl展开更多
Based on the fact that recycling of combined filter backwash water（CFBW）directly to drinking water treatment plants（WTP）is considered to be a feasible method to enhance pollutant removal efficiency,we were motivat...Based on the fact that recycling of combined filter backwash water（CFBW）directly to drinking water treatment plants（WTP）is considered to be a feasible method to enhance pollutant removal efficiency,we were motivated to evaluate the genotoxicity of water samples from two pilot-scale drinking water treatment systems,one with recycling of combined backwash water,the other one with a conventional process.An integrated approach of the comet and micronucleus（MN）assays was used with zebrafish（Danio rerio）to investigate the water genotoxicity in this study.The total organic carbon（TOC）,dissolved organic carbon（DOC）,and trihalomethane formation potential（THMFP）,of the recycling process were lower than that of the conventional process.All the results showed that there was no statistically significant difference（P〉0.05）between the conventional and recycling processes,and indicated that the genotoxicity of water samples from the recycling process did not accumulate in 15 day continuous recycling trial.It was worth noting that there was correlation between the concentrations of TOC,DOC,UV（254）,and THMFPs in water and the DNA damage score,with corresponding R^2 values of 0.68,0.63,0.28,and 0.64.Nevertheless,both DNA strand breaks and MN frequency of all water samples after disinfection were higher than that of water samples from the two treatment units,which meant that the disinfection by-products（DBPs）formed by disinfection could increase the DNA damage.Both the comet and MN tests suggest that the recycling process did not increase the genotoxicity risk,compared to the traditional process.展开更多
Cadmium (Cd) is one of the important pollutants of soil and the genotoxicity of Cd-contaminated soil was studied in combination with imidacloprid. The single cell gel electro-phoresis or comet assay was used to quanti...Cadmium (Cd) is one of the important pollutants of soil and the genotoxicity of Cd-contaminated soil was studied in combination with imidacloprid. The single cell gel electro-phoresis or comet assay was used to quantify DNA strand breaks as a measure of DNA damage induced by Cd and imidacloprid contamination in soil. The soil was artificially contaminated by Cd (0.0, 0.2, 0.5, 1.0, 2.0 mg·kg-1 dry soil) or Cd (0.0, 0.2, 0.5, 1.0, 2.0 mg·kg-1 dry soil) and imidacloprid (0.5 mg-kg^1 dry soil). Roots of Vicia faba were exposed to the contaminated soil for 2 h at 25℃ and were used in the comet assay. DNA damage was measured as the values of percentage of nuclei with tails, tail length, tail DNA, tail moment (TM), and Olive tail moment (OTM). DNA damages of root tips of Vicia faba increased after Cd treatment and there were dose-related increases in DNA damage measured as these parameters. However, the addition of imidacloprid further increased the DNA damage. These data confirmed the genotoxic effect of Cd to plants, and that the combined pollution with imidacloprid can enhance the genotoxicity of Cd.展开更多
Objective Alkaline comet assay was used to evaluate DNA repair (nucleotide excision repair, NER) capacity of human fresh lymphocytes from 12 young healthy non-smokers (6 males and 6 females). Methods Lymphocytes were ...Objective Alkaline comet assay was used to evaluate DNA repair (nucleotide excision repair, NER) capacity of human fresh lymphocytes from 12 young healthy non-smokers (6 males and 6 females). Methods Lymphocytes were exposed to UV-C (254 nm) at the dose rate of 1.5 J/m2/sec. Novobiocin (NOV) and aphidicolin (APC), DNA repair inhibitors, were utilized to imitate the deficiency of DNA repair capacity at the incision and ligation steps of NER. Lymphocytes from each donor were divided into three grougs: UVC group, UVC plus NOV group, and UVC plus APC group. DNA single strand breaks were detected in UVC irradiated cells incubated for 0, 30, 60, 90, 120, 180, and 240 min after UVC irradiation. DNA repair rate (DRR) served as an indicator of DNA repair capacity. Results The results indicated that the maximum DNA damage (i.e. maximum tail length) in the UVC group mainly appeared at 90 min. The ranges of DRRs in the UVC group were 62.84%-98.71%. Average DRR value was 81.84%. The DRR difference between males and females was not significant (P<0.05). However, the average DRR value in the UVC plus NOV group and the UVC plus APC group was 52.98% and 39.57% respectively, which were significantly lower than that in the UVC group (P<0.01). Conclusion The comet assay is a rapid, simple and sensitive screening test to assess individual DNA repair (NER) capacity. It is suggested that the time to detect DNA single strand breaks in comet assay should include 0 (before UV irradiation), 90 and 240 min after exposure to 1.5 J·m-2 UVC at least. The DRR, as an indicator, can represent the individual DNA repair capacity in comet assay.展开更多
基金This research was supported by Postgraduate Innovative Foundation of Harbin Medical University (No. HCXB2006008)the Grant from Health Bureau of Heilongjiang Province (No. 2005-91).
文摘Objective To detect the oxidative DNA damage in diabetic patients and to investigate the relationship of oxidative DNA damage with diabetes and diabetic nephropathy. Methods Single cell gel electrophoresis （SCGE） was used to detect the DNA strand breaks in peripheral blood lymphocytes, and oxidative DNA damage product and serum 8-OHdG were determined by a competitive ELISA in 47 cases, including 25 patients without diabetic complications, 22 patients with diabetic nephropathy and 25 normal control subjects. Results Diabetic patients showed greater oxidative damage to DNA. The percentage of comet cells and the length of DNA migration （comet tail length） of peripheral blood lymphocytes were significantly increased in patients with diabetes, and significantly higher in patients with diabetic nephropathy than in diabetic patients without vascular complications （P〈0.05）. There was a significant increase in serum 8-OHdG in diabetic patients compared with normal subjects （P〈0.05）. Moreover, serum 8-OHdG was much higher in patients with diabetic nephropathy than in diabetic patients without vascular complications （P〈0.05）. Coneluslon There is severe oxidative DNA damage in diabetic patients. Enhanced oxidative stress may be associated with diabetes, especially in patients with diabetic nephropathy.
文摘Among the different DNA anomalies that can be present in the male gamete, DNA fragmentation is the most frequent, particularly in infertile subjects. There is now consistent evidence that a sperm containing fragmented DNA can be alive, motile, morphologically normal and able to fertilize an oocyte. There is also evidence that the oocyte is able to repair DNA damage; however, the extent of this repair depends on the type of DNA damage present in the sperm, as well as on the quality of the oocyte. Thus, it is important to understand the possible consequences of sperm DNA fragmentation （SDF） for embryo development, implantation, pregnancy outcome and the health of progeny conceived, both naturally and by assisted reproductive technology （ART）. At present, data on the consequences of SDF for reproduction are scarce and, in many ways, inconsistent. The differences in study conclusions might result from the different methods used to detect SDF, the study design and the inclusion criteria. Consequently, it is difficult to decide whether SDF testing should be carried out in fertility assessment and ART. It is clear that there is an urgent need for the standardisation of the methods and for additional clinical studies on the impact of SDF on ART outcomes.
文摘Aims: Anaemia is a common comorbidity in chronic heart failure(CHF). The predictors of new onset anaemia(NOA) and its long-term prognostic value, particularly in patients treated with beta-blockers, are not known. Methods and results: In COMET, 3029 patients with CHF in NYHA Ⅱ-IV and EF< 35%were randomized to carvedilol or metoprolol tartrate and were followed for an average of 58 months. Plasma haemoglobin(Hb) concentrations were measured at a central laboratory at randomization, at four monthly intervals for the first year and annually thereafter. According to WHO criteria, anaemia was defined when Hb measured< 13 g/dL for men and< 12 g/dL for women. We considered anaemia to be severe when Hb< 11.5 g/dL for men and< 10.5 g/dL for women. The baseline mean Hb was 14.2±1.5 g/dL(n=2996) and 15.9%of patients had anaemia(males, 16.0%; females, 15.2%). At baseline, severe anaemia was found in 3.3%of patients(males, 3.6%; females, 2.0%). During the study, all-cause mortality(RR 1.47) death or hospitalization(RR 1.28), and heart failure hospitalization(RR 1.43, all P< 0.0001) were higher in anaemic when compared with non-anaemic patients. In patients without anaemia at baseline, at the end of the study, the cumulative frequency of NOA was 28.1%in males and 27.0%in females. NOA increased over time from 14.2%at year 1 to 27.5%at year 5. Predictors of NOA were: higher age, diuretic dose, creatinine(all P< 0.0001), higher serum potassium, lower serum sodium, body mass index, and use of aldosterone antagonists, carvedilol, and digitalis(all P< 0.03). Treatment with carvedilol(vs. metoprolol tartrate) was associated with a 24%increased risk to develop NOA(P=0.0047),but not severe anaemia(P=0.18). Patients with a Hb decrease of >3 g/dL(RR 3.37, P< 0.0001) or of 2.0-3.0 g/dL(RR 1.47, P=0.011) from baseline had an increased subsequent mortality when compared with patients having Hb increases of 0-1.0 g/dL. Conclusion: In stable ambulatory CHF patients, development of NOA is frequent and can be predicted by a set of clinical v
文摘针对C/S(Client/Server)架构下的OPC(OLE for Process Control)实时监控系统在互联网应用中的局限,采用ASP.NET和Comet技术,提出了一种B/S(Browser/Server)架构下OPC实时监控系统的设计和实现。该方案只需在客户端安装支持Ajax技术的浏览器即可正常工作,通过与采用其他技术实现此系统的方案的对比研究,发现该方案具有较好的易用性、跨平台性。对OPC-DA(OPC-Data Access)连接组件进行了改进和封装,使其更加符合实际应用的需要。模拟实验结果表明,采用Comet技术的方案在保证较好的实时性的同时,服务器的开销也较小,是一种满足Web应用实时性需求的可行方案。
基金This work was supported by the Natural Science Foundation of Zhejiang Province (No.300434), 2001-2003, and International Cooperation Foundation of Science-Technique Bureau of Zhejiang Province (No. 012104), 2001-2002.
文摘Objective To determine the interaction between 2450-MHz microwaves (MW) radiation and mitomycin C (MMC). Methods The synergistic genotoxic effects of low-intensity 2450-MHz microwave and MMC on human lymphocytes were studied using single cell gel electrophoresis (SCGE) assay (comet assay) and cytokinesis-blocked micronucleus (CBMN) test in vitro. The whole blood cells from a male donor and a female donor were either only exposed to 2450-MHz microwaves (5.0 mW/cm2) for 2 h or only exposed to MMC (0.0125 μ/mL, 0.025 μg/mL, 0.05μg/mL and 0.1 μg/mL) for 24 h; and the samples were exposed to MMC for 24 h after exposure to MW for 2 h. Results In the comet assay, the comet lengths ( 29.1 μm and 25.9 μm) of MW were not significantly longer than those (26.3 μrn and 24.1 μm) of controls (P>0.05). The comet lengths (57.4 μm, 68.9 μm, 91.4 μm, 150.6μm and 50.6 μm, 71.7μm, 100.1 μm, 145.1 μm) of 4 MMC groups were significantly longer than those of controls (P<0.01). The comet lengths (59.1 μm, 92.3 μm, 124.5 μm, 182.7 μm and 57.4 μm, 85.5 μm, 137.5 μm, 178.3 μm) of 4 MW plus MMC groups were significantly longer than those of controls too (P<0.01). The comet lengths of MW plus MMC groups were significantly longer than those of the corresponding MMC doses (P<0.05 or P<0.01) when the doses of MMC were ≥50.025 μg/mL. In the CBMN, the micronucleated cell (MNC) rates of MW were 5% and 6%, which showed no difference compared with those (4‰ and 4‰) of controls (P>0.05). The MNC rates of 4 MMC groups were 8‰, 9‰, 14‰, 23‰ and 8‰, 8‰, 16‰, 30‰ respectively. When the doses of MMC were 3≥0.05 μg/mL, MNC rates of MMC were higher than those of controls (P<0.05). MNC rates of 4 MW plus MMC groups were 12‰, 13‰, 20‰, 32‰ and 8‰, 9‰, 23‰, 40‰. When the doses of MMC were 5≥0.05 μg/mL, MNC rates of MW plus MMC groups were much higher than those of controls (P<0.01). MNC rates of 4 MW plus MMC groups were not significantly higher than those of the corresponding MMC doses. Concl
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment(Nos.2012ZX07408001,2014ZX07405002)the National Natural Science Foundation of China(No.51108118)the State Key Laboratory of Urban Water Resource and Environment(No.2013DX12)
文摘Based on the fact that recycling of combined filter backwash water（CFBW）directly to drinking water treatment plants（WTP）is considered to be a feasible method to enhance pollutant removal efficiency,we were motivated to evaluate the genotoxicity of water samples from two pilot-scale drinking water treatment systems,one with recycling of combined backwash water,the other one with a conventional process.An integrated approach of the comet and micronucleus（MN）assays was used with zebrafish（Danio rerio）to investigate the water genotoxicity in this study.The total organic carbon（TOC）,dissolved organic carbon（DOC）,and trihalomethane formation potential（THMFP）,of the recycling process were lower than that of the conventional process.All the results showed that there was no statistically significant difference（P〉0.05）between the conventional and recycling processes,and indicated that the genotoxicity of water samples from the recycling process did not accumulate in 15 day continuous recycling trial.It was worth noting that there was correlation between the concentrations of TOC,DOC,UV（254）,and THMFPs in water and the DNA damage score,with corresponding R^2 values of 0.68,0.63,0.28,and 0.64.Nevertheless,both DNA strand breaks and MN frequency of all water samples after disinfection were higher than that of water samples from the two treatment units,which meant that the disinfection by-products（DBPs）formed by disinfection could increase the DNA damage.Both the comet and MN tests suggest that the recycling process did not increase the genotoxicity risk,compared to the traditional process.
文摘Cadmium (Cd) is one of the important pollutants of soil and the genotoxicity of Cd-contaminated soil was studied in combination with imidacloprid. The single cell gel electro-phoresis or comet assay was used to quantify DNA strand breaks as a measure of DNA damage induced by Cd and imidacloprid contamination in soil. The soil was artificially contaminated by Cd (0.0, 0.2, 0.5, 1.0, 2.0 mg·kg-1 dry soil) or Cd (0.0, 0.2, 0.5, 1.0, 2.0 mg·kg-1 dry soil) and imidacloprid (0.5 mg-kg^1 dry soil). Roots of Vicia faba were exposed to the contaminated soil for 2 h at 25℃ and were used in the comet assay. DNA damage was measured as the values of percentage of nuclei with tails, tail length, tail DNA, tail moment (TM), and Olive tail moment (OTM). DNA damages of root tips of Vicia faba increased after Cd treatment and there were dose-related increases in DNA damage measured as these parameters. However, the addition of imidacloprid further increased the DNA damage. These data confirmed the genotoxic effect of Cd to plants, and that the combined pollution with imidacloprid can enhance the genotoxicity of Cd.
文摘Objective Alkaline comet assay was used to evaluate DNA repair (nucleotide excision repair, NER) capacity of human fresh lymphocytes from 12 young healthy non-smokers (6 males and 6 females). Methods Lymphocytes were exposed to UV-C (254 nm) at the dose rate of 1.5 J/m2/sec. Novobiocin (NOV) and aphidicolin (APC), DNA repair inhibitors, were utilized to imitate the deficiency of DNA repair capacity at the incision and ligation steps of NER. Lymphocytes from each donor were divided into three grougs: UVC group, UVC plus NOV group, and UVC plus APC group. DNA single strand breaks were detected in UVC irradiated cells incubated for 0, 30, 60, 90, 120, 180, and 240 min after UVC irradiation. DNA repair rate (DRR) served as an indicator of DNA repair capacity. Results The results indicated that the maximum DNA damage (i.e. maximum tail length) in the UVC group mainly appeared at 90 min. The ranges of DRRs in the UVC group were 62.84%-98.71%. Average DRR value was 81.84%. The DRR difference between males and females was not significant (P<0.05). However, the average DRR value in the UVC plus NOV group and the UVC plus APC group was 52.98% and 39.57% respectively, which were significantly lower than that in the UVC group (P<0.01). Conclusion The comet assay is a rapid, simple and sensitive screening test to assess individual DNA repair (NER) capacity. It is suggested that the time to detect DNA single strand breaks in comet assay should include 0 (before UV irradiation), 90 and 240 min after exposure to 1.5 J·m-2 UVC at least. The DRR, as an indicator, can represent the individual DNA repair capacity in comet assay.
