Aim: To evaluate in vitro the effectiveness of several anti-infective agents alone or in combination against Mycobacterium smegmatis. Method: A convenient stratified sampling method was used to obtain selected anti-in...Aim: To evaluate in vitro the effectiveness of several anti-infective agents alone or in combination against Mycobacterium smegmatis. Method: A convenient stratified sampling method was used to obtain selected anti-infective agents. For individual drug samples, Minimum Inhibitory Concentrations (MIC) were obtained using the agar-well plate diffusion technique. Fractional Inhibitory Concentration Indices (FICI) were calculated for drug combinations using their MIC as obtained from the broth dilution method. Results: Of the thirty (30) anti-infective agents analyzed, ten (10) had MIC equivalent to or better than rifampicin (reference TB drug). Seven (7) drugs had MIC higher than rifampicin, while twelve (12) showed no growth inhibition of M. smegmatis. Analysis of the effect of drug combinations on M. smegmatis indicated that four (4) combinations, including rifampicin/ethambutol showed synergism. One (1) was additive, two (2) were indifferent and one (1) combination showed antagonism. Conclusion: Notable in the results obtained was the high effectiveness of the carbapenems in inhibiting the growth of M. smegmatis. Carbapenems, though not indicated for TB treatment, has a potential of playing a significant role in the treatment of tuberculosis. Also the drug combinations which showed synergism, especially those that involved the macrolide antibiotics, should further be investigated. These results have to be confirmed by in vivo clinical studies to define their roles in tuberculosis treatment.展开更多
目的:探讨不同浓度重组Canstatin蛋白对碱烧伤后小鼠角膜基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)及其组织抑制剂-2(tissue inhibitor of metalloproteinase-2,TIMP-2)表达的影响及其调节作用。方法:BALB/c小鼠60只随机分...目的:探讨不同浓度重组Canstatin蛋白对碱烧伤后小鼠角膜基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)及其组织抑制剂-2(tissue inhibitor of metalloproteinase-2,TIMP-2)表达的影响及其调节作用。方法:BALB/c小鼠60只随机分为实验组A、实验B及对照组C,每组20只。采用1mol/L氢氧化钠溶液烧伤小鼠右眼角膜,建立炎症性角膜碱烧伤动物模型,分别予以A组、B组重组Canstatin蛋白3μg/mL、5μg/mL点右眼,4次/d,对照组C组予以生理眼水点右眼。在碱烧伤后第1、3、7、14d以形态学分析评价角膜上皮损伤面积及新生血管生长的情况,并于碱烧伤后第1、3、7、14d应用Western-blot检测角膜MMP-2和TIMP-2的表达,增强化学发光法(ECL)对结果进行分析。结果:形态学分析显示,A组和B组小鼠在碱烧伤后第3d起各时间点角膜上皮缺损面积均小于对照组(P<0.01),角膜新生血管均得到抑制,CNV面积明显小于对照组(P<0.01)。Western-blot结果显示,碱烧伤后各时间点MMP-2的表达,A组和B组均明显低于对照组(P<0.01),TIMP-2的表达高于对照组(P<0.01),且A组和B组间MMP-2的表达在第14d比较差异有统计学意义(P<0.05),TIMP-2的表达在第7d及第14d比较差异有统计学意义(P<0.05)。结论:重组Canstatin蛋白可通过抑制角膜细胞及浸润的炎性细胞产生MMP-2,促进TIMP-2表达,从而抑制和延迟碱烧伤后角膜融解的发生和发展,对碱烧伤后角膜的重塑起着重要作用。展开更多
猪繁殖与呼吸综合征(Porcine reproductive and respiratory syndrome,PRRS)俗称猪蓝耳病,是由病毒引起的一种高度接触性传染病,可导致母猪晚期流产、早产、死胎、木乃伊胎等繁殖障碍和仔猪严重的呼吸道症状及高死亡率。该病毒已在全世...猪繁殖与呼吸综合征(Porcine reproductive and respiratory syndrome,PRRS)俗称猪蓝耳病,是由病毒引起的一种高度接触性传染病,可导致母猪晚期流产、早产、死胎、木乃伊胎等繁殖障碍和仔猪严重的呼吸道症状及高死亡率。该病毒已在全世界范围内广泛流行,给养殖业造成了重大的经济损失。目前,传统的疫苗无法提供完全的保护作用,开发研制新型疫苗已迫在眉睫。PRRSV基因组长约15kb,有8个不同程度的开放阅读框(ORFS),即ORF1-ORF7。该病毒具有3个重要的结构蛋白,即E蛋白,M蛋白和N蛋白,这三种蛋白分别由病毒基因ORF5,ORF6和ORF7编码。本试验构建了含猪繁殖与呼吸综合征病毒E+M+N基因的重组腺病毒。首先用反转录聚合酶链反应(RT-PCR)的方法分别扩增出猪繁殖与呼吸综合征病毒E基因、M基因和N基因,将三者用口蹄疫病毒2A序列串联起来,将连接好的E+M+N基因插入腺病毒穿梭载体pAdTrack-CMV。将获得的重组穿梭质粒和腺病毒骨架载体pAdEasy-1在大肠杆菌BJ5183内进行同源重组,获得了插有外源基因的重组腺病毒质粒pAd/E+M+N;最后,经PacⅠ酶切线性化后转染HEK-293细胞,成功地得到含有E+M+N基因的重组腺病毒,为重组腺病毒活载体疫苗的研究奠定基础。展开更多
文摘Aim: To evaluate in vitro the effectiveness of several anti-infective agents alone or in combination against Mycobacterium smegmatis. Method: A convenient stratified sampling method was used to obtain selected anti-infective agents. For individual drug samples, Minimum Inhibitory Concentrations (MIC) were obtained using the agar-well plate diffusion technique. Fractional Inhibitory Concentration Indices (FICI) were calculated for drug combinations using their MIC as obtained from the broth dilution method. Results: Of the thirty (30) anti-infective agents analyzed, ten (10) had MIC equivalent to or better than rifampicin (reference TB drug). Seven (7) drugs had MIC higher than rifampicin, while twelve (12) showed no growth inhibition of M. smegmatis. Analysis of the effect of drug combinations on M. smegmatis indicated that four (4) combinations, including rifampicin/ethambutol showed synergism. One (1) was additive, two (2) were indifferent and one (1) combination showed antagonism. Conclusion: Notable in the results obtained was the high effectiveness of the carbapenems in inhibiting the growth of M. smegmatis. Carbapenems, though not indicated for TB treatment, has a potential of playing a significant role in the treatment of tuberculosis. Also the drug combinations which showed synergism, especially those that involved the macrolide antibiotics, should further be investigated. These results have to be confirmed by in vivo clinical studies to define their roles in tuberculosis treatment.
文摘目的:探讨不同浓度重组Canstatin蛋白对碱烧伤后小鼠角膜基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)及其组织抑制剂-2(tissue inhibitor of metalloproteinase-2,TIMP-2)表达的影响及其调节作用。方法:BALB/c小鼠60只随机分为实验组A、实验B及对照组C,每组20只。采用1mol/L氢氧化钠溶液烧伤小鼠右眼角膜,建立炎症性角膜碱烧伤动物模型,分别予以A组、B组重组Canstatin蛋白3μg/mL、5μg/mL点右眼,4次/d,对照组C组予以生理眼水点右眼。在碱烧伤后第1、3、7、14d以形态学分析评价角膜上皮损伤面积及新生血管生长的情况,并于碱烧伤后第1、3、7、14d应用Western-blot检测角膜MMP-2和TIMP-2的表达,增强化学发光法(ECL)对结果进行分析。结果:形态学分析显示,A组和B组小鼠在碱烧伤后第3d起各时间点角膜上皮缺损面积均小于对照组(P<0.01),角膜新生血管均得到抑制,CNV面积明显小于对照组(P<0.01)。Western-blot结果显示,碱烧伤后各时间点MMP-2的表达,A组和B组均明显低于对照组(P<0.01),TIMP-2的表达高于对照组(P<0.01),且A组和B组间MMP-2的表达在第14d比较差异有统计学意义(P<0.05),TIMP-2的表达在第7d及第14d比较差异有统计学意义(P<0.05)。结论:重组Canstatin蛋白可通过抑制角膜细胞及浸润的炎性细胞产生MMP-2,促进TIMP-2表达,从而抑制和延迟碱烧伤后角膜融解的发生和发展,对碱烧伤后角膜的重塑起着重要作用。
文摘猪繁殖与呼吸综合征(Porcine reproductive and respiratory syndrome,PRRS)俗称猪蓝耳病,是由病毒引起的一种高度接触性传染病,可导致母猪晚期流产、早产、死胎、木乃伊胎等繁殖障碍和仔猪严重的呼吸道症状及高死亡率。该病毒已在全世界范围内广泛流行,给养殖业造成了重大的经济损失。目前,传统的疫苗无法提供完全的保护作用,开发研制新型疫苗已迫在眉睫。PRRSV基因组长约15kb,有8个不同程度的开放阅读框(ORFS),即ORF1-ORF7。该病毒具有3个重要的结构蛋白,即E蛋白,M蛋白和N蛋白,这三种蛋白分别由病毒基因ORF5,ORF6和ORF7编码。本试验构建了含猪繁殖与呼吸综合征病毒E+M+N基因的重组腺病毒。首先用反转录聚合酶链反应(RT-PCR)的方法分别扩增出猪繁殖与呼吸综合征病毒E基因、M基因和N基因,将三者用口蹄疫病毒2A序列串联起来,将连接好的E+M+N基因插入腺病毒穿梭载体pAdTrack-CMV。将获得的重组穿梭质粒和腺病毒骨架载体pAdEasy-1在大肠杆菌BJ5183内进行同源重组,获得了插有外源基因的重组腺病毒质粒pAd/E+M+N;最后,经PacⅠ酶切线性化后转染HEK-293细胞,成功地得到含有E+M+N基因的重组腺病毒,为重组腺病毒活载体疫苗的研究奠定基础。
