目的 探究老年导管相关尿路感染(catheter-associated urinary tract infection, CAUTI)中微生物群落的动态变化及其抗生素耐药性的发展,以期对CAUTI的预防和治疗策略提供新的理论依据。方法 本前瞻性队列研究共纳入30名老年导管尿路感...目的 探究老年导管相关尿路感染(catheter-associated urinary tract infection, CAUTI)中微生物群落的动态变化及其抗生素耐药性的发展,以期对CAUTI的预防和治疗策略提供新的理论依据。方法 本前瞻性队列研究共纳入30名老年导管尿路感染患者,分为CAUTI组(n=15)和对照组(n=15)。通过16S rRNA基因测序技术分析微生物种类,使用Kirby-Bauer纸片扩散法进行抗生素敏感性测试,并采用统计学方法比较两组间微生物群落结构和抗生素耐药性的差异。结果 两组患者的一般人口学特征相似。在微生物群落结构分析中,CAUTI组患者样本中大肠埃希菌属、葡萄球菌属和链球菌属的丰度显著高于对照组(大肠埃希菌属9.25%±2.44%vs 8.00%±2.49%,P<0.05;葡萄球菌属9.38%±2.70%vs 7.03%±2.17%,P<0.05;链球菌属10.09%±2.65%vs 8.95%±3.73%,P<0.05)。α多样性指数中,Simpson指数在CAUTI组有显著下降(0.58±0.31 vs 0.77±0.26,P<0.05)。β多样性分析揭示两组微生物群落分布存在显著差异。抗生素敏感性测试结果表明,CAUTI组抑菌圈直径普遍小于对照组(β内酰胺类18.45±1.23 mm vs 20.67±1.56 mm,P<0.05;喹诺酮类21.57±1.78 mm vs 23.89±1.45 mm,P<0.05;大环内酯类19.32±1.65 mm vs 22.43±1.29 mm,P<0.05)。CAUTI组耐药菌株比例显著高于对照组(46.7%vs 20%,P<0.05)。结论 CAUTI患者的尿液和导尿管样本中微生物群落组成存在显著差异,且表现出更高的抗生素耐药性。这些数据表明CAUTI的临床治疗需要更加关注抗生素的合理选择和使用,同时也提示了未来研究需要关注微生物群落对治疗响应的影响。展开更多
为了解聚糖菌在污泥颗粒化中的脱氮能力及其微生物生态特性,采用反应器工艺、批式试验、显微技术和荧光原位杂交技术来评估其反硝化能力,揭示其微生物群落的微观结构,探索聚糖菌和聚磷菌在不同粒径污泥中的分布特征.结果表明,污泥对有...为了解聚糖菌在污泥颗粒化中的脱氮能力及其微生物生态特性,采用反应器工艺、批式试验、显微技术和荧光原位杂交技术来评估其反硝化能力,揭示其微生物群落的微观结构,探索聚糖菌和聚磷菌在不同粒径污泥中的分布特征.结果表明,污泥对有机物的吸收率稳定在90%以上.颗粒污泥的沉降指数(SVI10)稳定在30-50 mL g-1,远低于接种污泥的108.2 mL g-1.聚醣菌颗粒污泥对硝酸盐氮和亚硝酸盐氮的反硝化去除率分别达到了65%和70%,氮气为主要气态产物.聚糖菌颗粒污泥被大量的四联球菌结构所充斥,丝状菌在其中起到了重要的构架和搭桥的作用.荧光原位杂交结果表明聚糖菌可生存于各尺寸颗粒化污泥内;而聚磷菌受到严重抑制只能较少地分布在颗粒污泥的外围空间.上述结果表明,在SBR反应器中采用厌氧搅拌—排水—好氧曝气的处理模式成功培育出具有聚糖特性的颗粒化微生物聚集体,培育成功的颗粒污泥对硝酸盐氮和亚硝酸盐氮均具有良好的反硝化特性.在整体颗粒污泥微生物群落中聚糖菌为优势种群.展开更多
The bioleaching of two different types of low-grade copper tailings,acid-leaching tailings(ALT)and copper flotation tailings(CFT)by mixed moderate thermophiles,and the variation of mineralogical and microbiological ch...The bioleaching of two different types of low-grade copper tailings,acid-leaching tailings(ALT)and copper flotation tailings(CFT)by mixed moderate thermophiles,and the variation of mineralogical and microbiological characteristics during their dissolution processes were comparatively investigated.Results showed that bioleaching behaviors of the two types of tailings were significantly different.In ALT bioleaching,lower redox potential,higher[Fe3+]/[Fe2+]ratio and higher cell density in solution were obtained.These resulted in higher total copper,primary copper sulfide and secondary copper sulfide extractions,compared with CFT bioleaching.X-ray diffraction analysis suggested that gypsum and some metal organic complexes were detected in CFT bioleaching,which could cause the sluggish oxidation of sulphide minerals.The shifts of microbial community in the leachates and leaching residues varied greatly between ALT and CFT bioleaching.The percentage of iron-oxidizing bacteria in ALT bioleaching was higher than that of CFT,but the sulfur-oxidizing bacteria percentage was the opposite.The archaeon F.thermophilum L1 was detected in ALT but not in CFT.展开更多
Microbial activities are affected by a myriad of factors with end points involved in nutrient cycling and carbon sequestration issues.Because of their prominent role in the global carbon balance and their possible rol...Microbial activities are affected by a myriad of factors with end points involved in nutrient cycling and carbon sequestration issues.Because of their prominent role in the global carbon balance and their possible role in carbon sequestration, soil microbes are very important organisms in relation to global climate changes. This review focuses mainly on the responses of soil microbes to climate changes and subsequent effects on soil carbon dynamics. An overview table regarding extracellular enzyme activities(EAA) with all relevant literature data summarizes the effects of different ecosystems under various experimental treatments on EAA. Increasing temperature, altered soil moisture regimes, and elevated carbon dioxide significantly affect directly or indirectly soil microbial activities.High temperature regimes can increase the microbial activities which can provide positive feedback to climate change, whereas lower moisture condition in pedosystem can negate the increase, although the interactive effects still remain unanswered. Shifts in soil microbial community in response to climate change have been determined by gene probing, phospholipid fatty acid analysis(PLFA),terminal restriction length polymorphism(TRFLP), and denaturing gradient gel electrophoresis(DGGE), but in a recent investigations,omic technological interventions have enabled determination of the shift in soil microbe community at a taxa level, which can provide very important inputs for modeling C sequestration process. The intricacy and diversity of the soil microbial population and how it responds to climate change are big challenges, but new molecular and stable isotope probing tools are being developed for linking fluctuations in microbial diversity to ecosystem function.展开更多
文摘目的 探究老年导管相关尿路感染(catheter-associated urinary tract infection, CAUTI)中微生物群落的动态变化及其抗生素耐药性的发展,以期对CAUTI的预防和治疗策略提供新的理论依据。方法 本前瞻性队列研究共纳入30名老年导管尿路感染患者,分为CAUTI组(n=15)和对照组(n=15)。通过16S rRNA基因测序技术分析微生物种类,使用Kirby-Bauer纸片扩散法进行抗生素敏感性测试,并采用统计学方法比较两组间微生物群落结构和抗生素耐药性的差异。结果 两组患者的一般人口学特征相似。在微生物群落结构分析中,CAUTI组患者样本中大肠埃希菌属、葡萄球菌属和链球菌属的丰度显著高于对照组(大肠埃希菌属9.25%±2.44%vs 8.00%±2.49%,P<0.05;葡萄球菌属9.38%±2.70%vs 7.03%±2.17%,P<0.05;链球菌属10.09%±2.65%vs 8.95%±3.73%,P<0.05)。α多样性指数中,Simpson指数在CAUTI组有显著下降(0.58±0.31 vs 0.77±0.26,P<0.05)。β多样性分析揭示两组微生物群落分布存在显著差异。抗生素敏感性测试结果表明,CAUTI组抑菌圈直径普遍小于对照组(β内酰胺类18.45±1.23 mm vs 20.67±1.56 mm,P<0.05;喹诺酮类21.57±1.78 mm vs 23.89±1.45 mm,P<0.05;大环内酯类19.32±1.65 mm vs 22.43±1.29 mm,P<0.05)。CAUTI组耐药菌株比例显著高于对照组(46.7%vs 20%,P<0.05)。结论 CAUTI患者的尿液和导尿管样本中微生物群落组成存在显著差异,且表现出更高的抗生素耐药性。这些数据表明CAUTI的临床治疗需要更加关注抗生素的合理选择和使用,同时也提示了未来研究需要关注微生物群落对治疗响应的影响。
文摘为了解聚糖菌在污泥颗粒化中的脱氮能力及其微生物生态特性,采用反应器工艺、批式试验、显微技术和荧光原位杂交技术来评估其反硝化能力,揭示其微生物群落的微观结构,探索聚糖菌和聚磷菌在不同粒径污泥中的分布特征.结果表明,污泥对有机物的吸收率稳定在90%以上.颗粒污泥的沉降指数(SVI10)稳定在30-50 mL g-1,远低于接种污泥的108.2 mL g-1.聚醣菌颗粒污泥对硝酸盐氮和亚硝酸盐氮的反硝化去除率分别达到了65%和70%,氮气为主要气态产物.聚糖菌颗粒污泥被大量的四联球菌结构所充斥,丝状菌在其中起到了重要的构架和搭桥的作用.荧光原位杂交结果表明聚糖菌可生存于各尺寸颗粒化污泥内;而聚磷菌受到严重抑制只能较少地分布在颗粒污泥的外围空间.上述结果表明,在SBR反应器中采用厌氧搅拌—排水—好氧曝气的处理模式成功培育出具有聚糖特性的颗粒化微生物聚集体,培育成功的颗粒污泥对硝酸盐氮和亚硝酸盐氮均具有良好的反硝化特性.在整体颗粒污泥微生物群落中聚糖菌为优势种群.
基金Projects(31570113,41573072)supported by the National Natural Science Foundation of China
文摘The bioleaching of two different types of low-grade copper tailings,acid-leaching tailings(ALT)and copper flotation tailings(CFT)by mixed moderate thermophiles,and the variation of mineralogical and microbiological characteristics during their dissolution processes were comparatively investigated.Results showed that bioleaching behaviors of the two types of tailings were significantly different.In ALT bioleaching,lower redox potential,higher[Fe3+]/[Fe2+]ratio and higher cell density in solution were obtained.These resulted in higher total copper,primary copper sulfide and secondary copper sulfide extractions,compared with CFT bioleaching.X-ray diffraction analysis suggested that gypsum and some metal organic complexes were detected in CFT bioleaching,which could cause the sluggish oxidation of sulphide minerals.The shifts of microbial community in the leachates and leaching residues varied greatly between ALT and CFT bioleaching.The percentage of iron-oxidizing bacteria in ALT bioleaching was higher than that of CFT,but the sulfur-oxidizing bacteria percentage was the opposite.The archaeon F.thermophilum L1 was detected in ALT but not in CFT.
文摘Microbial activities are affected by a myriad of factors with end points involved in nutrient cycling and carbon sequestration issues.Because of their prominent role in the global carbon balance and their possible role in carbon sequestration, soil microbes are very important organisms in relation to global climate changes. This review focuses mainly on the responses of soil microbes to climate changes and subsequent effects on soil carbon dynamics. An overview table regarding extracellular enzyme activities(EAA) with all relevant literature data summarizes the effects of different ecosystems under various experimental treatments on EAA. Increasing temperature, altered soil moisture regimes, and elevated carbon dioxide significantly affect directly or indirectly soil microbial activities.High temperature regimes can increase the microbial activities which can provide positive feedback to climate change, whereas lower moisture condition in pedosystem can negate the increase, although the interactive effects still remain unanswered. Shifts in soil microbial community in response to climate change have been determined by gene probing, phospholipid fatty acid analysis(PLFA),terminal restriction length polymorphism(TRFLP), and denaturing gradient gel electrophoresis(DGGE), but in a recent investigations,omic technological interventions have enabled determination of the shift in soil microbe community at a taxa level, which can provide very important inputs for modeling C sequestration process. The intricacy and diversity of the soil microbial population and how it responds to climate change are big challenges, but new molecular and stable isotope probing tools are being developed for linking fluctuations in microbial diversity to ecosystem function.
