Acute myocardial infarction(AMI) is the leading cause of death worldwide. Its associated mortality, morbidity and complications have significantly decreased with the development of interventional cardiology and percut...Acute myocardial infarction(AMI) is the leading cause of death worldwide. Its associated mortality, morbidity and complications have significantly decreased with the development of interventional cardiology and percutaneous coronary angioplasty(PCA) treatment, which quick-ly and effectively restore the blood flow to the area previously subjected to ischemia. Paradoxi-cally, the restoration of blood flow to the ischemic zone leads to a massive production of reactive oxygen species(ROS) which generate rapid and severe damage to biomolecules, generating a phenomenon called myocardial reperfusion injury(MRI). In the clinical setting, MRI is associated with multiple complications such as lethal reperfusion, no-reflow, myocardial stunning, and reperfusion arrhythmias. Despite significant advances in the understanding of the mechanisms accounting for the myocardial ischemia reperfusion injury, it remains an unsolved problem. Although promising results have been obtained in experimental studies(mainly in animal models), these benefits have not been translated into clinical settings. Thus, clinical trials have failed to find benefits from any therapy to prevent MRI. There is major evidence with respect to the contribution of oxidative stress to MRI in cardiovascular diseases. The lack- of consistency between basic studies and clinical trials is not solely based on the diversity inherent in epidemiology but is also a result of the methodological weak-nesses of some studies. It is quite possible that pharmacological issues, such as doses, active ingredients, bioavailability, routes of administration, co-therapies, startup time of the drug intervention,and its continuity may also have some responsibility for the lack- of consistency between different studies. Furthermore, the administration of high ascorbate doses prior to reperfusion appears to be a safe and rational therapy against the development of oxidative damage associated with myocardial reperfusion. In addition, the association with N-acetylcysteine(a glutathione do展开更多
AIM： To assess the efficacy of premedicaton with pronase or N-acetylcysteine （NAC） at 20 min before upper gastrointestinal （UGI） endoscopy and to determine whether pronase or NAC pretreatment influences the relia...AIM： To assess the efficacy of premedicaton with pronase or N-acetylcysteine （NAC） at 20 min before upper gastrointestinal （UGI） endoscopy and to determine whether pronase or NAC pretreatment influences the reliability of the rapid urease test. METHODS： A total of 146 patients were prospectively and randomly assigned into the study groups according to different premedications before endoscopy. One endoscopist assessed mucosal visibility （MV） with scores ranged from 1 to 4 at four sites in the stomach. The sum of the MV scores from these four locations was defined as the total mucosal visibility （TMV） score. Identification of Hpylori was performed using CLO test, histology, and serology. RESULTS： The Group with pronase premedication had a significantly lower TMV score than did the groups with gascon and gascon water （P 〈 0.001 and P 〈 0.01, respectively）. The group with NAC had a significantly lower TMV score than the group with gascon （P 〈 0.01） and a trend of a lower MV score than the group with gascon water （P = 0.06）. The THV score did not significantly differ between the group with pronase and the group with NAC （P = 0.39 and P = 0.14, respectively）. The sensitivity and specifidty of the CLO test were 92.5% and 93.9%, respectively, in groups premedicated with pronase and NAC together.CONCLUSION： Premedication with pronase or NAC at 20 min before UGI endoscopy improves the mucosal visibility of the stomach. Neither pronase nor NAC produces any obvious interference with the CLO test for the identification of H pylori infection.展开更多
Background Obstructive sleep apnea syndrome （OSAS） is an important risk factor for cardiovascular diseases. Chronic intermittent hypoxia （CIH） is considered to be one of the most important causes of cardiovascular...Background Obstructive sleep apnea syndrome （OSAS） is an important risk factor for cardiovascular diseases. Chronic intermittent hypoxia （CIH） is considered to be one of the most important causes of cardiovascular diseases in OSA patients. This repeated hypoxia and reoxygenation cycle is similar to hypoxia-reperfusion injury, which initiates oxidative stress. In this study, we observed cardiocytes injury induced by CIH and the effect of N-acetylcysteine （NAC）. Methods Thirty ICR mice were randomly assigned to 3 groups： control, CIH and NAC （CIH＋NAC） groups. Malondialdehyde （MDA） and superoxide dismutase （SOD） of cardiocyte homogenates were measured. Serum lipids were measured by an instrument method. Serum cardiac troponin I （cTnl） was detected by enzyme-linked immunosorbent assays （ELISA）. Myocardium pathological sections were observed. Results （1） The SOD activity and MDA concentration of cardiocyte homogenates in the CIH group were significantly higher than in other groups （P 〈0.005）. The MDA concentration of the NAC group was lower than that of the control group （P 〈0.01）. （2） The serum cTnl concentration of the CIH and NAC groups was significantly higher than that of the control group （P 〈0.01）. （3） Serum triglyceride levels in the NAC group were lower than in the other groups （P 〈0.01）, while there were no significant differences in low density lipoprotein and high density lipoprotein among the three groups. （4） The degeneration of myocardium, transverse striation blurred, and fabric effusion were observed in tissue sections in the CIH and NAC groups. However, normal tissue was found in the control group. Conclusion The oxidative stress induced by CIH can injure cardiocytes and the injury effect can be partially inhibited by NAC.展开更多
文摘Acute myocardial infarction(AMI) is the leading cause of death worldwide. Its associated mortality, morbidity and complications have significantly decreased with the development of interventional cardiology and percutaneous coronary angioplasty(PCA) treatment, which quick-ly and effectively restore the blood flow to the area previously subjected to ischemia. Paradoxi-cally, the restoration of blood flow to the ischemic zone leads to a massive production of reactive oxygen species(ROS) which generate rapid and severe damage to biomolecules, generating a phenomenon called myocardial reperfusion injury(MRI). In the clinical setting, MRI is associated with multiple complications such as lethal reperfusion, no-reflow, myocardial stunning, and reperfusion arrhythmias. Despite significant advances in the understanding of the mechanisms accounting for the myocardial ischemia reperfusion injury, it remains an unsolved problem. Although promising results have been obtained in experimental studies(mainly in animal models), these benefits have not been translated into clinical settings. Thus, clinical trials have failed to find benefits from any therapy to prevent MRI. There is major evidence with respect to the contribution of oxidative stress to MRI in cardiovascular diseases. The lack- of consistency between basic studies and clinical trials is not solely based on the diversity inherent in epidemiology but is also a result of the methodological weak-nesses of some studies. It is quite possible that pharmacological issues, such as doses, active ingredients, bioavailability, routes of administration, co-therapies, startup time of the drug intervention,and its continuity may also have some responsibility for the lack- of consistency between different studies. Furthermore, the administration of high ascorbate doses prior to reperfusion appears to be a safe and rational therapy against the development of oxidative damage associated with myocardial reperfusion. In addition, the association with N-acetylcysteine(a glutathione do
基金Supported by a grant of TMU93-AE1-B-0793 MSH-TMU-09 of Taipei Medical University
文摘AIM： To assess the efficacy of premedicaton with pronase or N-acetylcysteine （NAC） at 20 min before upper gastrointestinal （UGI） endoscopy and to determine whether pronase or NAC pretreatment influences the reliability of the rapid urease test. METHODS： A total of 146 patients were prospectively and randomly assigned into the study groups according to different premedications before endoscopy. One endoscopist assessed mucosal visibility （MV） with scores ranged from 1 to 4 at four sites in the stomach. The sum of the MV scores from these four locations was defined as the total mucosal visibility （TMV） score. Identification of Hpylori was performed using CLO test, histology, and serology. RESULTS： The Group with pronase premedication had a significantly lower TMV score than did the groups with gascon and gascon water （P 〈 0.001 and P 〈 0.01, respectively）. The group with NAC had a significantly lower TMV score than the group with gascon （P 〈 0.01） and a trend of a lower MV score than the group with gascon water （P = 0.06）. The THV score did not significantly differ between the group with pronase and the group with NAC （P = 0.39 and P = 0.14, respectively）. The sensitivity and specifidty of the CLO test were 92.5% and 93.9%, respectively, in groups premedicated with pronase and NAC together.CONCLUSION： Premedication with pronase or NAC at 20 min before UGI endoscopy improves the mucosal visibility of the stomach. Neither pronase nor NAC produces any obvious interference with the CLO test for the identification of H pylori infection.
基金This study was supported by the grants from National Natural Science Foundation of China （No. 30770954） and the Nanjing Technology Plan Projects （No. 20080253） and Jiangsu Province College Students Practical Innovative Training Plan Projects （No. 2007012）.
文摘Background Obstructive sleep apnea syndrome （OSAS） is an important risk factor for cardiovascular diseases. Chronic intermittent hypoxia （CIH） is considered to be one of the most important causes of cardiovascular diseases in OSA patients. This repeated hypoxia and reoxygenation cycle is similar to hypoxia-reperfusion injury, which initiates oxidative stress. In this study, we observed cardiocytes injury induced by CIH and the effect of N-acetylcysteine （NAC）. Methods Thirty ICR mice were randomly assigned to 3 groups： control, CIH and NAC （CIH＋NAC） groups. Malondialdehyde （MDA） and superoxide dismutase （SOD） of cardiocyte homogenates were measured. Serum lipids were measured by an instrument method. Serum cardiac troponin I （cTnl） was detected by enzyme-linked immunosorbent assays （ELISA）. Myocardium pathological sections were observed. Results （1） The SOD activity and MDA concentration of cardiocyte homogenates in the CIH group were significantly higher than in other groups （P 〈0.005）. The MDA concentration of the NAC group was lower than that of the control group （P 〈0.01）. （2） The serum cTnl concentration of the CIH and NAC groups was significantly higher than that of the control group （P 〈0.01）. （3） Serum triglyceride levels in the NAC group were lower than in the other groups （P 〈0.01）, while there were no significant differences in low density lipoprotein and high density lipoprotein among the three groups. （4） The degeneration of myocardium, transverse striation blurred, and fabric effusion were observed in tissue sections in the CIH and NAC groups. However, normal tissue was found in the control group. Conclusion The oxidative stress induced by CIH can injure cardiocytes and the injury effect can be partially inhibited by NAC.
