Jadomycin is an antibiotic that has shown activities against bacteria, yeasts and fungi as well as cytotoxic properties to cancer cells. Because of the wide range of its inhibitory actions, jadomycin shows promise as ...Jadomycin is an antibiotic that has shown activities against bacteria, yeasts and fungi as well as cytotoxic properties to cancer cells. Because of the wide range of its inhibitory actions, jadomycin shows promise as a novel antibiotic and cancer treatment drug. Streptomyces venezuelae are aerobic bacteria that produce jadomycin and the size of bacterial population can significantly affect the yield of jadomycin. Therefore, the bacterial population must be accurately measured in order to standardize the reproducibility of jadomycin production process. In this study, a dehydrogenase activity measurement test, using triphenyl tetrazolium chloride (TTC), was used to measure the dehydrogenase activity of Streptomyces venezuelae during growth in maltose-yeast extract-malt extract (MYM) broth. The aims were to evaluate the effectiveness of the test for measuring microbial growth and to study the effects of the test conditions (incubation time, incubation temperature and medium pH) on triphenyl formazan (TF) yield. The results showed that the TF yield was highly correlated to the optical density. The highest TF yield was observed at a pH of 6 at all incubation times and temperature. Lower TF yields were obtained at higher temperature (40 and 50oC) compared to those obtained at lower temperatures (22 and 30oC). The difference between the yields obtained at 22oC and 30oC were not significant. The differences between incubation time were also not significant. The recommended test conditions are an incubation time of 1 hour at a temperature of 30oC and a pH of 6 followed by three extractions using methanol.展开更多
The present study aimed to explore the mechanism underlying the protective effects of hydrogen sulfide against neuronal damage caused by cerebral ischemia/reperfusion. We established the middle cerebral artery occlusi...The present study aimed to explore the mechanism underlying the protective effects of hydrogen sulfide against neuronal damage caused by cerebral ischemia/reperfusion. We established the middle cerebral artery occlusion model in rats via the suture method. Ten minutes after middle cerebral artery occlusion, the animals were intraperitoneally injected with hydrogen sulfide donor compound sodium hydrosulfide. Immunofluorescence revealed that the immunoreactivity of P2X7 in the cerebral cortex and hippocampal CA1 region in rats with cerebral ischemia/reperfusion injury decreased with hydrogen sulfide treatment. Furthermore, treatment of these rats with hydrogen sulfide significantly lowered mortality, the Longa neurological deficit scores, and infarct volume. These results indicate that hydrogen sulfide may be protective in rats with local cerebral ischemia/reperfusion injury by down-regulating the expression of P2X7 receptors.展开更多
目的评估抑制泛素羧基末端水解酶L1(UCHL1)对小鼠脑缺血/再灌注损伤的影响。方法将雄性BALB/c小鼠随机分为假手术(sham)组、缺血/再灌注(I/R)组、UCHL1小干扰RNA(siRNA)组和scramble si RNA(control)组,每组10只小鼠。采用小鼠大脑中动...目的评估抑制泛素羧基末端水解酶L1(UCHL1)对小鼠脑缺血/再灌注损伤的影响。方法将雄性BALB/c小鼠随机分为假手术(sham)组、缺血/再灌注(I/R)组、UCHL1小干扰RNA(siRNA)组和scramble si RNA(control)组,每组10只小鼠。采用小鼠大脑中动脉闭塞(MCAO)60 min后再灌注24 h建立I/R模型。其中si RNA组和control组在MCAO前24 h将10μl UCHL1 si RNA或scramble si RNA通过侧脑室注入脑内。采用RTPCR和Western blotting方法检测各组小鼠脑组织中UCHL1表达;采用2,3,5-氯化三苯基四氮唑(TTC)染色法评估各组小鼠脑梗死体积和水肿率;采用神经行为学评分法评估各组小鼠神经症状评分。结果与sham组相比,I/R组缺血半影区UCHL1 m RNA和蛋白水平显著增高(P<0.05);而si RNA组UCHL1蛋白和mRNA表达明显降低(P<0.05);与此同时,I/R组小鼠脑梗死体积、水肿率及神经行为学损伤明显增加,而si RNA组小鼠脑梗死体积和水肿率及神经行为学损伤进一步加重(P<0.05)。结论抑制UCHL1可加重小鼠脑缺血/再灌注损伤。提示,MCAO后诱导UCHL1表达对小鼠脑缺血/再灌注损伤具有保护作用。展开更多
文摘Jadomycin is an antibiotic that has shown activities against bacteria, yeasts and fungi as well as cytotoxic properties to cancer cells. Because of the wide range of its inhibitory actions, jadomycin shows promise as a novel antibiotic and cancer treatment drug. Streptomyces venezuelae are aerobic bacteria that produce jadomycin and the size of bacterial population can significantly affect the yield of jadomycin. Therefore, the bacterial population must be accurately measured in order to standardize the reproducibility of jadomycin production process. In this study, a dehydrogenase activity measurement test, using triphenyl tetrazolium chloride (TTC), was used to measure the dehydrogenase activity of Streptomyces venezuelae during growth in maltose-yeast extract-malt extract (MYM) broth. The aims were to evaluate the effectiveness of the test for measuring microbial growth and to study the effects of the test conditions (incubation time, incubation temperature and medium pH) on triphenyl formazan (TF) yield. The results showed that the TF yield was highly correlated to the optical density. The highest TF yield was observed at a pH of 6 at all incubation times and temperature. Lower TF yields were obtained at higher temperature (40 and 50oC) compared to those obtained at lower temperatures (22 and 30oC). The difference between the yields obtained at 22oC and 30oC were not significant. The differences between incubation time were also not significant. The recommended test conditions are an incubation time of 1 hour at a temperature of 30oC and a pH of 6 followed by three extractions using methanol.
基金financially supported by grants from the National Natural Science Foundation of China,No.81371346,81271376Outstanding Postgraduate Fund of Xinxiang Medical UniversityScience and Technology Key Research Project of Henan Provincial Education Department of China,No.14A310019
文摘The present study aimed to explore the mechanism underlying the protective effects of hydrogen sulfide against neuronal damage caused by cerebral ischemia/reperfusion. We established the middle cerebral artery occlusion model in rats via the suture method. Ten minutes after middle cerebral artery occlusion, the animals were intraperitoneally injected with hydrogen sulfide donor compound sodium hydrosulfide. Immunofluorescence revealed that the immunoreactivity of P2X7 in the cerebral cortex and hippocampal CA1 region in rats with cerebral ischemia/reperfusion injury decreased with hydrogen sulfide treatment. Furthermore, treatment of these rats with hydrogen sulfide significantly lowered mortality, the Longa neurological deficit scores, and infarct volume. These results indicate that hydrogen sulfide may be protective in rats with local cerebral ischemia/reperfusion injury by down-regulating the expression of P2X7 receptors.
文摘目的评估抑制泛素羧基末端水解酶L1(UCHL1)对小鼠脑缺血/再灌注损伤的影响。方法将雄性BALB/c小鼠随机分为假手术(sham)组、缺血/再灌注(I/R)组、UCHL1小干扰RNA(siRNA)组和scramble si RNA(control)组,每组10只小鼠。采用小鼠大脑中动脉闭塞(MCAO)60 min后再灌注24 h建立I/R模型。其中si RNA组和control组在MCAO前24 h将10μl UCHL1 si RNA或scramble si RNA通过侧脑室注入脑内。采用RTPCR和Western blotting方法检测各组小鼠脑组织中UCHL1表达;采用2,3,5-氯化三苯基四氮唑(TTC)染色法评估各组小鼠脑梗死体积和水肿率;采用神经行为学评分法评估各组小鼠神经症状评分。结果与sham组相比,I/R组缺血半影区UCHL1 m RNA和蛋白水平显著增高(P<0.05);而si RNA组UCHL1蛋白和mRNA表达明显降低(P<0.05);与此同时,I/R组小鼠脑梗死体积、水肿率及神经行为学损伤明显增加,而si RNA组小鼠脑梗死体积和水肿率及神经行为学损伤进一步加重(P<0.05)。结论抑制UCHL1可加重小鼠脑缺血/再灌注损伤。提示,MCAO后诱导UCHL1表达对小鼠脑缺血/再灌注损伤具有保护作用。
