Given their unique structure-dependent properties,strategically designing semiconductor-based photocatalysts,which expose highly reactive crystalline facets,is widely used to tune their performance.Herein,AgBr/Ag/TiO_...Given their unique structure-dependent properties,strategically designing semiconductor-based photocatalysts,which expose highly reactive crystalline facets,is widely used to tune their performance.Herein,AgBr/Ag/TiO_(2){100}nanorods Z-scheme heterojunction composites were prepared via hydrothermal and in situ facet-induced reduction.Transmission electron microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,electron paramagnetic resonance spectroscopy,and density functional theory calculations reveal that the selective exposure of TiO_(2){100}facets with abundant oxygen vacancies(OV)promotes the formation of metallic silver on the interfaces between AgBr and TiO_(2){100}.Metallic silver can mediate interfacial charge transfer by facilitating the photogenerated carrier recombination of the conduction band of TiO_(2){100}and the valence band of AgBr.As a result,a Z-scheme heterojunction is formed in AgBr/Ag/TiO_(2){100}.The AgBr/Ag/TiO_(2){100}exhibits faster degradation of tetracycline in aqueous solution compared to pristine AgBr,TiO_(2){101},TiO_(2){100}and AgBr/TiO_(2){101}p-n heterojunctions.This is attributed to the effect of the Z-scheme heterojunction on prolonging the lifetime of photogenerated carriers,which is confirmed by femtosecond transient absorption spectroscopy.The photocatalytic mechanism and degradation pathways are discussed along with a toxicity assessment of the intermediates.Overall,this work develops a new approach for designing Z-scheme heterojunction photocatalysts via selective facet control of anatase TiO_(2).展开更多
【背景】酪蛋白水解蛋白酶L(caseinolytic protease L,ClpL)是热休克蛋白100(heat shock protein 100,HSP100)家族成员,参与多种细胞内生物学过程包括应激耐受反应、长期存活、毒力和抗生素抗性等,在病原菌的致病过程中发挥重要作用。...【背景】酪蛋白水解蛋白酶L(caseinolytic protease L,ClpL)是热休克蛋白100(heat shock protein 100,HSP100)家族成员,参与多种细胞内生物学过程包括应激耐受反应、长期存活、毒力和抗生素抗性等,在病原菌的致病过程中发挥重要作用。【目的】阐明HSP100/ClpL对猪链球菌2型(Streptococcus suis type 2)强毒株的应激耐受和毒力的影响。【方法】利用温敏自杀质粒pSET4s构建了SsClpL基因缺失株ΔclpL;利用大肠杆菌-猪链球菌穿梭质粒pSET2构建了互补株CΔclpL;比较亲本株SS2-1、ΔclpL和CΔclpL在各种应激环境(高温、氧化性应激和酸应激)和血液中的生存能力;利用小鼠感染模型和体内竞争试验评价clpL缺失前后细菌的毒力变化。【结果】clpL缺失后,SS2在各种应激环境中的生存能力明显减弱;同时在猪全血中的存活能力也显著降低;对BALB/c小鼠的致病力有所降低,在体内的定殖能力明显降低。【结论】SsClpL与猪链球菌的应激耐受和致病性密切相关。展开更多
目的探析脑梗死患者髓鞘碱性蛋白(myelin basic protein,MBP)、S100钙结合蛋白B(S100 calcium-binding protein B,S100-B)水平与介入治疗后早期神经功能恶化的关联性。方法纳入2021年7月–2024年7月期间本院收治的258例脑梗死患者,采用...目的探析脑梗死患者髓鞘碱性蛋白(myelin basic protein,MBP)、S100钙结合蛋白B(S100 calcium-binding protein B,S100-B)水平与介入治疗后早期神经功能恶化的关联性。方法纳入2021年7月–2024年7月期间本院收治的258例脑梗死患者,采用美国国立卫生研究院卒中量表(National Institutes of Health Stroke Scale,NIHSS)评分评估患者的神经功能状况,将死亡患者或介入治疗24 h后NIHSS评分增加4分及以上患者纳入早期神经功能恶化组,其余患者纳入未恶化组。测定所有患者MBP、S100-B水平,并分析其水平变化与介入治疗后神经功能恶化风险的关系。结果脑梗死患者早期神经功能恶化组血清MBP、S100-B水平高于未恶化组〔t=9.062(95%CI:2.348~3.663)、7.708(95%CI:0.221~0.375),P<0.001〕;Spearman相关性显示:恶化组血清MBP、S100-B水平与NIHSS评分增加情况呈正相关〔r=0.323(95%CI:0.095~0.542)、0.292(95%CI:0.066~0.488),P<0.05〕;分层回归分析显示:血清MBP〔比值比(odds ratio,OR)=1.996,95%CI:1.607~2.478〕、S100-B(OR=1.005,95%CI:1.003~1.007)水平是影响脑梗死患者早期神经功能恶化的危险因素(P<0.05),即使校正混杂因素后依然是其危险因素,此外入院NIHSS评分(OR=1.224,95%CI:1.142~1.310)及合并高血压(OR=2.542,95%CI:1.139~5.669)、高脂血症(OR=2.618,95%CI:1.101~6.228),其中入院NIHSS评分与MBP存在交互作用(OR=1.081,95%CI:1.034~1.130);受试者工作特征曲线显示:血清MBP、S100-B水平评估脑梗死患者早期神经功能恶化的曲线下面积分别为0.822(95%CI:0.764~0.879)、0.788(95%CI:0.724~0.853)。结论脑梗死患者介入治疗后血清MBP、S100-B水平较高与早期神经功能恶化风险相关,且对神经功能恶化风险有一定的评估价值。展开更多
文摘Given their unique structure-dependent properties,strategically designing semiconductor-based photocatalysts,which expose highly reactive crystalline facets,is widely used to tune their performance.Herein,AgBr/Ag/TiO_(2){100}nanorods Z-scheme heterojunction composites were prepared via hydrothermal and in situ facet-induced reduction.Transmission electron microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,electron paramagnetic resonance spectroscopy,and density functional theory calculations reveal that the selective exposure of TiO_(2){100}facets with abundant oxygen vacancies(OV)promotes the formation of metallic silver on the interfaces between AgBr and TiO_(2){100}.Metallic silver can mediate interfacial charge transfer by facilitating the photogenerated carrier recombination of the conduction band of TiO_(2){100}and the valence band of AgBr.As a result,a Z-scheme heterojunction is formed in AgBr/Ag/TiO_(2){100}.The AgBr/Ag/TiO_(2){100}exhibits faster degradation of tetracycline in aqueous solution compared to pristine AgBr,TiO_(2){101},TiO_(2){100}and AgBr/TiO_(2){101}p-n heterojunctions.This is attributed to the effect of the Z-scheme heterojunction on prolonging the lifetime of photogenerated carriers,which is confirmed by femtosecond transient absorption spectroscopy.The photocatalytic mechanism and degradation pathways are discussed along with a toxicity assessment of the intermediates.Overall,this work develops a new approach for designing Z-scheme heterojunction photocatalysts via selective facet control of anatase TiO_(2).
文摘【背景】酪蛋白水解蛋白酶L(caseinolytic protease L,ClpL)是热休克蛋白100(heat shock protein 100,HSP100)家族成员,参与多种细胞内生物学过程包括应激耐受反应、长期存活、毒力和抗生素抗性等,在病原菌的致病过程中发挥重要作用。【目的】阐明HSP100/ClpL对猪链球菌2型(Streptococcus suis type 2)强毒株的应激耐受和毒力的影响。【方法】利用温敏自杀质粒pSET4s构建了SsClpL基因缺失株ΔclpL;利用大肠杆菌-猪链球菌穿梭质粒pSET2构建了互补株CΔclpL;比较亲本株SS2-1、ΔclpL和CΔclpL在各种应激环境(高温、氧化性应激和酸应激)和血液中的生存能力;利用小鼠感染模型和体内竞争试验评价clpL缺失前后细菌的毒力变化。【结果】clpL缺失后,SS2在各种应激环境中的生存能力明显减弱;同时在猪全血中的存活能力也显著降低;对BALB/c小鼠的致病力有所降低,在体内的定殖能力明显降低。【结论】SsClpL与猪链球菌的应激耐受和致病性密切相关。
文摘目的探析脑梗死患者髓鞘碱性蛋白(myelin basic protein,MBP)、S100钙结合蛋白B(S100 calcium-binding protein B,S100-B)水平与介入治疗后早期神经功能恶化的关联性。方法纳入2021年7月–2024年7月期间本院收治的258例脑梗死患者,采用美国国立卫生研究院卒中量表(National Institutes of Health Stroke Scale,NIHSS)评分评估患者的神经功能状况,将死亡患者或介入治疗24 h后NIHSS评分增加4分及以上患者纳入早期神经功能恶化组,其余患者纳入未恶化组。测定所有患者MBP、S100-B水平,并分析其水平变化与介入治疗后神经功能恶化风险的关系。结果脑梗死患者早期神经功能恶化组血清MBP、S100-B水平高于未恶化组〔t=9.062(95%CI:2.348~3.663)、7.708(95%CI:0.221~0.375),P<0.001〕;Spearman相关性显示:恶化组血清MBP、S100-B水平与NIHSS评分增加情况呈正相关〔r=0.323(95%CI:0.095~0.542)、0.292(95%CI:0.066~0.488),P<0.05〕;分层回归分析显示:血清MBP〔比值比(odds ratio,OR)=1.996,95%CI:1.607~2.478〕、S100-B(OR=1.005,95%CI:1.003~1.007)水平是影响脑梗死患者早期神经功能恶化的危险因素(P<0.05),即使校正混杂因素后依然是其危险因素,此外入院NIHSS评分(OR=1.224,95%CI:1.142~1.310)及合并高血压(OR=2.542,95%CI:1.139~5.669)、高脂血症(OR=2.618,95%CI:1.101~6.228),其中入院NIHSS评分与MBP存在交互作用(OR=1.081,95%CI:1.034~1.130);受试者工作特征曲线显示:血清MBP、S100-B水平评估脑梗死患者早期神经功能恶化的曲线下面积分别为0.822(95%CI:0.764~0.879)、0.788(95%CI:0.724~0.853)。结论脑梗死患者介入治疗后血清MBP、S100-B水平较高与早期神经功能恶化风险相关,且对神经功能恶化风险有一定的评估价值。
