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Molecular Detection of Extended-Spectrum Beta Lactamase and Carbapenemase Genes in Escherichia coli and Salmonella spp. Isolated from Chickens Consumed Outdoors in Ouagadougou, Burkina Faso
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作者 Amana Mètuor Dabiré Stéphanie Lynseh Carine Sita Bénao +4 位作者 Nicolas Ouédraogo Rahimatou Yasmine Wendkouni Tiemtoré Rhaina Olivia Badini Lionel Eliada Benoit Bambara Jacques Simporé 《Journal of Biosciences and Medicines》 2024年第11期221-232,共12页
This study was carried out to assess the prevalence of resistance genes in strains of Escherichia coli and Salmonella spp. isolated from free-range chickens in Ouagadougou, where resistant bacteria can be transmitted ... This study was carried out to assess the prevalence of resistance genes in strains of Escherichia coli and Salmonella spp. isolated from free-range chickens in Ouagadougou, where resistant bacteria can be transmitted to humans via faeces or contaminated meat. A total of 280 strains of Escherichia coli and 129 strains of Salmonella spp. resistant to at least one beta-lactam or carbapenem antibiotic were used in this study. PCR analyses revealed the presence of ESBL (extended spectrum beta lactamase) resistance genes in Escherichia coli isolates, with 3.21% (9/280) possessing the CTX-M (Cefotaximase) gene, 15.35% (43/280) had the SHV (Sulfhydril Variable) gene, and 11.42% (32/280) had carbapenemase resistance genes, more specifically IMP (Imipenemase metallo-beta-lactamase). As regards Salmonella spp. strains, only the presence of the SHV (Sulfhydril Variable) gene was identified in 2.32% (3/129) of isolates belonging to the ESBL family, while 26.35% (34/129) and 13.95% (18/129) of isolates respectively possessed the IMP (Imipenemase metallo-beta-lactamase) and NDM (New Delhi metallo-β-lactamase) genes, both of the carbapenemase type. The significant prevalence of resistance genes in bacterial strains isolated from chickens sold outdoors in Ouagadougou raises major public health concerns, due to the possible transmission of these resistant strains to humans through the consumption of contaminated meat, thus complicating the treatment of bacterial infections. 展开更多
关键词 BACTERIA Resistance Extended-Spectrum Beta lactamases CARBAPENEMASES OUAGADOUGOU
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Characterization of Extended Spectrum Beta-lactamase and Carbapenamase Producing Enterobacteriaceae Causing Urinary Tract Infection among Children in Kenya: A Cross-Sectional Study
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作者 Rachael Wangeci Waithaka Janet Kerubo Maranga Celestine Khalechi Makobe 《Advances in Microbiology》 CAS 2024年第7期351-365,共15页
Introduction: Enterobacteriaceae causing urinary tract infections (UTI) have developed resistance to the commonly used antibiotics due to emergence of Extended Spectrum Beta-Lactamases (ESBLs) and Carbapenamase produc... Introduction: Enterobacteriaceae causing urinary tract infections (UTI) have developed resistance to the commonly used antibiotics due to emergence of Extended Spectrum Beta-Lactamases (ESBLs) and Carbapenamase producing Enterobactericeae which are a public health problem worldwide. This study aims to determine the prevalence and characterize ESBLs and carbapenamase producing Enterobactericeae. Method: A cross-sectional study was carried out in Gertrude’s Children’s Hospital, Nairobi. 238 urine samples were collected from patients with urinary symptoms attending the outpatient department within the period 2020-2021. The urine were examined macroscopically and microscopically. Identification and antimicrobial susceptibility testing were done using VITEK® 2 Compact system (BioMérieux). Double disc synergy test and modified hodge tests were done as confirmatory tests for ESBLs and Carbapenamase phenotypes respectively. Polymerase Chain Reaction was used for the detection of blaCTX-M, blaTEM, blaSHV, blaKPC and blaOXA-48 genes. Results: From the 238 children sampled the prevalence of UTI caused by Enterobactericeae was 22.3%. The Enterobacteriaceae species isolated were Escherichia coli (84.9%), Klebsiella pneumoniae (5.66%), Proteus mirabillis (5.66%), Enterobacter aerogenes (1.89%) and Morganella morganii (1.89%). The isolated species were resistant to ampicillin. Meropenem had the highest susceptibility. Only E. coli species had the ESBLs (26.4%) and carbapenamase (1.9%) phenotypes. 100% had BlaCTX-M while 50% had blaTEM resistant gene. There was a significant association (p Conclusion: Ampicillin resistance resulted to use of alternative drugs and Meropenem was the drug of choice where increased resistance to the recommended drugs was noted. Further research on resistant genes is recommended. 展开更多
关键词 Enterobactericeae Urinary Tract Infection Prevalence Beta lactamases Polymerase Chain Reaction CHILDREN OUTPATIENT Antimicrobial Resistance PHENOTYPES Escherichia coli
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Characteristics of β-Lactamase Synthesis in E. coli and K. pneumanie Strains in Nosocomial Infections
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作者 Saddraddin A. Atakishizadeh Sayyaddin A. Atakishizadeh Mahammad M. Davudov 《Advances in Microbiology》 CAS 2024年第1期25-30,共6页
Background: Recently micro-organisms that synthesize extended-spectrum β-lactamase (ESBLs) were increased. The peculiarities of ESBL synthesis of Escherichia coli and Klebsiella pneumoniae strains that cause nosocomi... Background: Recently micro-organisms that synthesize extended-spectrum β-lactamase (ESBLs) were increased. The peculiarities of ESBL synthesis of Escherichia coli and Klebsiella pneumoniae strains that cause nosocomial urinary tract infections, surgical site infections and pneumonia in surgical clinic were studied. ESBL synthesis were observed 38.9% of E. coli strains obtained from urine, 92.3% of strains obtained from surgical site infections, and 50% of strains obtained from sputum. ESBL synthesis were observed 37.5% of K. pneumoniae strains obtained from urine, 85.7% of strains obtained from surgical site infections, and 60% of strains obtained from sputum. Different levels of ESBL synthesize of E. coli and K. pneumoniae strains isolated from different pattern is discussed. Conclusion. ESBL synthesis is common in E. coli and K. pneumoniae strains, which cause nosocomial infections. The frequency of occurrence of ESBL s synthesis among of these strains depends on clinical forms of nosocomial infections. 展开更多
关键词 Nosocomial Infectious Agents β-lactamase Synthesis E. coli and K. pneumoniae
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法舒地尔缓解β-淀粉样蛋白1-42诱导的SH-SY5Y细胞凋亡
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作者 郭敏芳 张慧宇 +3 位作者 章培军 苏琴 贾思玮 尉杰忠 《中国组织工程研究》 CAS 北大核心 2025年第23期4939-4946,共8页
背景:法舒地尔对阿尔茨海默病小鼠脑内的线粒体动力学有调节作用,并且可以抑制神经炎症,但能否调节线粒体自噬和NLRP3炎症小体进而减轻β-淀粉样蛋白毒性尚不清楚。目的:探究法舒地尔对β-淀粉样蛋白1-42诱导的人源神经母细胞瘤细胞株SH... 背景:法舒地尔对阿尔茨海默病小鼠脑内的线粒体动力学有调节作用,并且可以抑制神经炎症,但能否调节线粒体自噬和NLRP3炎症小体进而减轻β-淀粉样蛋白毒性尚不清楚。目的:探究法舒地尔对β-淀粉样蛋白1-42诱导的人源神经母细胞瘤细胞株SH-SY5Y凋亡和线粒体自噬以及NLRP3炎症小体的调节作用。方法:将SH-SY5Y细胞接种于孔板内,细胞贴壁后分3组干预:对照组不加入任何药物,模型组加入20μmol/L β-淀粉样蛋白1-42,法舒地尔组同时加入20μmol/L β-淀粉样蛋白1-42与15 mg/L法舒地尔,干预24 h后,采用MTT法检测细胞活性,TUNEL染色检测细胞凋亡,qRT-PCR和Western blot检测凋亡相关蛋白表达,免疫荧光染色和Western blot检测线粒体自噬相关蛋白表达,免疫荧光染色和Western blot检测NLRP3炎症小体相关蛋白表达。结果与结论:(1)与对照组比较,模型组细胞活性降低、凋亡率升高(P<0.05);与模型组比较,法舒地尔组细胞活性升高、凋亡率降低(P<0.05);(2)qRT-PCR和Western blot检测结果显示,与对照组比较,模型组细胞Bax mRNA与蛋白表达升高(P<0.05),Bcl-2 mRNA与蛋白表达降低(P<0.05);与模型组比较,法舒地尔组细胞Bax mRNA与蛋白表达降低(P<0.05),Bcl-2 mRNA与蛋白表达升高(P<0.05);(3)免疫荧光染色和Western blot检测结果显示,与对照组相比,模型组细胞PINK1、帕金森病蛋白和LC3蛋白表达降低(P<0.05),p62蛋白表达升高(P<0.05);与模型组相比,法舒地尔组细胞PINK1、帕金森病蛋白和LC3蛋白表达升高(P<0.05),p62蛋白表达降低(P<0.05);(4)免疫荧光染色和Western blot检测结果显示,与对照组相比,模型组细胞NLRP3、ASC、Caspase-1和白细胞介素1β蛋白表达升高(P<0.05);与模型组相比,法舒地尔组细胞NLRP3、ASC、Caspase-1和白细胞介素1β蛋白表达降低(P<0.05);(5)结果表明,法舒地尔可以减轻β-淀粉样蛋白1-42诱导的SH-SY5Y细胞凋亡,其机制可能与激活线粒体自噬且抑制NLRP3炎症小体激活有关。 展开更多
关键词 法舒地尔 Β-淀粉样蛋白 神经细胞 细胞凋亡 线粒体自噬 炎症小体
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ANGPTL4 TSP-1及CyPA与脑卒中后癫痫患者认知功能的关系
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作者 高灵利 方建 +2 位作者 李晓晖 李延红 耿智凡 《中国实用神经疾病杂志》 2025年第1期63-67,共5页
目的探讨血管生成素样蛋白4(ANGPTL4)、凝血酶敏感蛋白-1(TSP-1)、亲环素A(CyPA与脑卒中后癫痫患者认知功能的关系。方法选取2021-01—2022-12河南大学第一附属医院神经内科收治的100例脑卒中后癫痫病例进行观察,按简易精神状态量表(MM... 目的探讨血管生成素样蛋白4(ANGPTL4)、凝血酶敏感蛋白-1(TSP-1)、亲环素A(CyPA与脑卒中后癫痫患者认知功能的关系。方法选取2021-01—2022-12河南大学第一附属医院神经内科收治的100例脑卒中后癫痫病例进行观察,按简易精神状态量表(MMSE)划分认知障碍标准将患者分为认知障碍组(50例)和认知正常组(50例),应用酶联免疫吸附试验(ELISA)检测2组患者的血清ANGPTL4、TSP-1、CyPA水平,MMSE量表测评2组患者的认知功能。结果与认知正常组比较,认知障碍组患者MMSE评分降低,ANGPTL4、TSP-1、CyPA水平升高(P<0.05);与轻度认知障碍患者比较,中度认知障碍患者血清ANGPTL4、TSP-1、CyPA水平升高(P<0.05);与中度认知障碍患者比较,重度认知障碍患者血清ANGPTL4、TSP-1、CyPA水平升高(P<0.05)。在脑卒中后癫痫患者中,血清ANGPTL4、TSP-1、Cy PA与MMSE评分各维度均呈负相关(P<0.05)。结论脑卒中后癫痫会降低MMSE评分,提高患者血清ANGPTL4、TSP-1、CyPA水平。ANGPTL4、TSP-1、CyPA水平越高,患者认知功能障碍越严重。 展开更多
关键词 脑卒中后癫痫 血管生成素样蛋白4 凝血酶敏感蛋白-1 亲环素A 认知功能
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自旋-轨道耦合作用下极化激元凝聚中的调制不稳定性
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作者 陈海军 《原子与分子物理学报》 CAS 北大核心 2025年第6期136-143,共8页
利用线性稳定性分析方法,对存在自旋-轨道耦合(SOS)作用的二维极化激元玻色-爱因斯坦凝聚(BEC)系统中的调制不稳定性(MI)进行了研究.分析了组分内部,组分之间以及SOC相互作用对系统调制不稳定性的影响.结果显示,当系统内部不存在SOC作用... 利用线性稳定性分析方法,对存在自旋-轨道耦合(SOS)作用的二维极化激元玻色-爱因斯坦凝聚(BEC)系统中的调制不稳定性(MI)进行了研究.分析了组分内部,组分之间以及SOC相互作用对系统调制不稳定性的影响.结果显示,当系统内部不存在SOC作用,组分之间的相互作用为0,组分内部存在排斥作用时,不会出现调制不稳定性,组分内部存在吸引作用时,会出现调制不稳定性,并且调制不稳定性区间长度随吸引作用的增强而增加;组分之间相互作用不为0时,组分之间的相互作用以平方形式出现,其正负不会对调制不稳定性产生实质性影响.存在SOC相互作用时,SOC相互作用会引起增益谱曲线的不规则振荡,破坏原来的调制不稳定性区间. 展开更多
关键词 极化激元凝聚 调制不稳定性 自旋-轨道耦合 双分量
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双偶氮苯-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子的二阶非线性光学性质 被引量:1
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作者 张宇红 李博 +4 位作者 陈自然 李渊 徐友辉 张莉萍 何旭东 《原子与分子物理学报》 CAS 北大核心 2025年第2期15-23,共9页
使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与... 使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与电子吸收光谱,采用有效场FF方法研究了二阶非线性光学性质(NLO).研究结果表明,26个噻蒽四酮类衍生物分子的能隙在1.33—2.02 eV范围,归属于有机半导体;最低能量吸收峰波长在601.8~609.5nm范围;在增大分子的二阶非线性光学系数β_(μ)(或β_(0))值方面,含相同偶氮苯基团或含不同偶氮苯基团分别引入到二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮分子两侧的2,10位优于2,9位,在2,10位分别端接含推、拉基团的偶氮苯优于含相同给电子基团的偶氮苯.在偶氮苯苯环对位分别端接强吸电子基(-NO_(2))与强供电子基(如-N(CH_(3))_(2)、-N(Ph)_(3)、-N-苯基咔唑等)可增强体系的二阶非线性光学性能,获得性能良好的非线性光学材料. 展开更多
关键词 双偶氮 二苯并[b i]噻蒽-[2 3-b]苯-5 7 12 14-四酮 密度泛函理论 电子吸收光谱 二阶非线性光学性质
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Extended-spectrum β-lactamase controversies 被引量:3
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作者 GeorgeA.Jacoby 《中国感染与化疗杂志》 CAS 2006年第6期361-370,共10页
G.A.Jacoby 教授毕业于美国哈佛医学院,为国际知名的传染病学、微生物学和免疫学专家,曾长期担任美国麻省总医院传染病科医师,现任麻省 Lahey 医学中心传染病实验室主任,中国感染与化疗杂志特邀编委。长期以来 Jacoby 教授对细菌耐药机... G.A.Jacoby 教授毕业于美国哈佛医学院,为国际知名的传染病学、微生物学和免疫学专家,曾长期担任美国麻省总医院传染病科医师,现任麻省 Lahey 医学中心传染病实验室主任,中国感染与化疗杂志特邀编委。长期以来 Jacoby 教授对细菌耐药机制有深入研究,尤其对细菌(肺炎克雷伯菌、大肠埃希菌等)产生质粒介导的超广谱β内酰胺酶(ESBL)以及喹诺酮类的耐药机制研究。曾发表多篇有关上述专题的权威性论著。此次本刊特邀 Jacoby 教授撰写有关 ESBL 的新进展,文中阐述目前 ESBLs 除通常所指质粒介导β内酰胺酶中扩大了酶水解的底物谱导致细菌对头孢噻肟、头孢他啶、氨曲南等抗生素耐药外,还包括许多具有不同特点的β内酰胺酶,其中某些酶产自共生菌。除 ESBL 外,AmpC 酶和各种碳青霉烯β内酰胺酶也可导致细菌对上述抗生素耐药,因此临床微生物实验室准确检出和鉴别各种β内酰胺酶,对于临床选用适宜的抗茵药十分重要。美国 CLSI(过去称为 NCCLS)推荐采用两步法(筛选及确证)检测细菌产 ESBL;但有的学者认为测定抗茵药物对细菌的 MIC,如用药后 T>MIC 在50%以上即可达到满意疗效,无需检测细菌是否产 ESBL。目前认为碳青霉烯类抗生素治疗产 ESBL 菌感染的疗效最为满意,但由此可能引起细菌对该类药物耐药,值得关注。采用大剂量头孢吡肟或哌拉西林-三唑巴坦治疗产ESBL 菌感染是否有效尚有争论,临床上对β内酰胺类最为耐药的菌株往往对几乎所有现用抗菌药耐药。黏菌素(或多黏菌素 B)曾成功的用于治疗此种多重耐药菌感染。此外替莫西林(temocillin,一种对β内酰胺酶稳定的青霉素类)与替加环素(tigecvcline,为米诺环素衍生物)体外对产 ESBL 菌有抗菌作用,但尚无临床研究资料。 展开更多
关键词 ESBLs lactamase controversies Extended-spectrum 中国感染与化疗杂志 MIC AMPC
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基于TLR4 NF-κB通路-神经相关因子探究依达拉奉对急性脑梗死患者炎症反应与神经损伤的保护机制
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作者 李莉 姜雪 +1 位作者 姜荣格 李恳 《中国实用神经疾病杂志》 2025年第1期47-52,共6页
目的基于Toll样受体4(TLR4)核因子-κB(NF-κB)通路-神经相关因子探究依达拉奉对急性脑梗死(ACI)患者炎症反应与神经损伤的保护机制。方法选取2020-07—2023-07保定市第一中心医院收治的110例ACI患者,以随机数字表法分为观察组、对照组,... 目的基于Toll样受体4(TLR4)核因子-κB(NF-κB)通路-神经相关因子探究依达拉奉对急性脑梗死(ACI)患者炎症反应与神经损伤的保护机制。方法选取2020-07—2023-07保定市第一中心医院收治的110例ACI患者,以随机数字表法分为观察组、对照组,各55例,对照组给予阿替普酶溶栓,观察组给予阿替普酶溶栓联合依达拉奉治疗。比较2组疗效、神经功能[美国国立卫生研究院卒中量表(NIHSS)评分、改良Rankin评分]、TLR4 NF-κB通路指标(TLR4、NF-κB)、神经损伤相关因子[神经元特异性烯醇化酶(NSE)、中枢神经特异性蛋白(S-100β)、脑源性神经营养因子(BDNF)]、TLR4 NF-κB通路相关炎症因子[白介素-1β(IL-1β)、超敏C反应蛋白(hs-CRP)、肿瘤坏死因子(TNF-α)、五聚素3(PTX3)、脂蛋白相关磷脂酶A2(Lp-PLA2)]。结果观察组总有效率96.36%,高于对照组的83.64%(P<0.05)。治疗1、2周观察组NIHSS评分、改良Rankin评分均低于对照组(P<0.05),观察组TLR4、NF-κB均低于对照组(P<0.05)。相较于治疗前,2组治疗1、2周后S-100β、NSE水平明显下降,BDNF水平明显升高,观察组S-100β、NSE水平均低于对照组,BDNF水平高于对照组(P<0.05)。相较于治疗前,2组治疗1、2周后IL-1β、hs-CRP、TNF-α、PTX3、Lp-PLA2水平均明显下降,观察组IL-1β、hs-CRP、TNF-α、PTX3、Lp-PLA2水平均低于对照组(P<0.05)。结论依达拉奉对ACI患者的疗效显著,有利于缓解炎症反应,改善神经损伤,其保护机制可能与TLR4 NF-κB通路调控神经损伤、炎症反应相关因子有关。 展开更多
关键词 急性脑梗死 TOLL样受体4 核因子-ΚB 依达拉奉 TLR4 NF-κB通路
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Phenotypic Detection and Susceptibility Pattern for the Detection of Extended Spectrum β-Lactamase-Producing <i>Klebsiella pneumonia </i>Isolates in Nairobi, Kenya 被引量:2
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作者 Patrick Mutharia Ndiba 《Open Journal of Medical Microbiology》 2013年第2期91-94,共4页
Klebsiella pneumoniae is an opportunistic pathogen that is an important cause of nosocomial infections. Detection of ESBL producers’ poses a special challenge for clinical microbiology laboratories, although ESBL pro... Klebsiella pneumoniae is an opportunistic pathogen that is an important cause of nosocomial infections. Detection of ESBL producers’ poses a special challenge for clinical microbiology laboratories, although ESBL producing pathogens are able to hydrolyze extended-spectrum penicillins, cephalosporins, and aztreonam, the minimum inhibitory concentrations (MIC) of some and perhaps even all of these agents may be within the susceptible range. The third generation cephalosporins have the reputation for being useful against a broad range of bacterial infections. However, resistance to these agents is something that must still be considered and creates obstacles for their clinical use. A total of 80 multi drug resistant clinical isolates of Klebsiella pneumoniae were obtained from a study on anaerobes associated with Pelvic Inflammatory disease (P.I.D), KEMRI S.S.C No.495. The isolates were identified by standard microbiological procedures. Antimicrobial susceptibility testing was carried out by Kirby-Bauer method. Upon identification, the antibiogram profiles of the isolates were determined and those resistant to third-generation cephalosporins were tested for production of ESBL. ESBL production among the multi drug resistant isolates was detected using the phenotypic confirmatory disc diffusion test (PCDDT) and double disk synergy test (DDST). While using standard double disk synergy test (DDST) as screening method for identifying potential ESBL producers, ceftriaxone was the most efficient antimicrobial in screening isolates as potential ESBL producers followed by cefotaxime. 展开更多
关键词 EXTENDED SPECTRUM β lactamases (ESBL) Double Disk Synergy TEST PHENOTYPIC Confirmatory Disc Diffusion TEST (PCDDT)
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L1 β-Lactamase催化反应机理研究 被引量:1
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作者 徐定国 鄢国森 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2008年第12期2453-2456,共4页
用混合量子力学和分子力学(QM/MM)方法和密度泛函理论讨论了L1β-Lactamase催化Nitrocefin水解的过程,研究结果表明,反应为多步反应:第一步亲核进攻反应为反应的决速步骤,并且伴随着酰胺键的断裂,第二步反应为质子迁移反应.同时讨论了... 用混合量子力学和分子力学(QM/MM)方法和密度泛函理论讨论了L1β-Lactamase催化Nitrocefin水解的过程,研究结果表明,反应为多步反应:第一步亲核进攻反应为反应的决速步骤,并且伴随着酰胺键的断裂,第二步反应为质子迁移反应.同时讨论了金属锌在反应中的作用. 展开更多
关键词 混合量子力学和分子力学(QM/MM) 密度泛函理论 Β-lactamase 水解反应
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T4-like coliphage ΦKAZ14 virulent to pathogenic and extended spectrum β-lactamase-producing Escherichia coli of poultry origin 被引量:1
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作者 Kaikabo Adamu Ahmad Abdulkarim Sabo Mohanmmed +1 位作者 Faridah Abas Sieo Chin Chin 《Virologica Sinica》 SCIE CAS CSCD 2015年第1期73-75,共3页
Dear Editor,Bacteriophages(otherwise called phages)are a type of virus that infect bacteria.This viral type has found useful applications in the control of bacterial pathogens in foods and food processing environments... Dear Editor,Bacteriophages(otherwise called phages)are a type of virus that infect bacteria.This viral type has found useful applications in the control of bacterial pathogens in foods and food processing environments.In addition,phages may be useful to prevent colonization and shedding of bacteria into the surrounding environment. 展开更多
关键词 producing PATHOGENIC lactamase ESBL otherwise environments phage chicken POULTRY avian
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Analysis of AmpC β-lactamase Gene in Pseudomonas aeruginosa 被引量:1
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作者 倪明 张东绅 齐俊英 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2005年第1期17-19,23,共4页
The gene and the amino acid sequence of the structural and regulatory region of the Pseudomonas aeruginosa with different resistance patterns were analyzed. Six strains with different resistance patterns were selected... The gene and the amino acid sequence of the structural and regulatory region of the Pseudomonas aeruginosa with different resistance patterns were analyzed. Six strains with different resistance patterns were selected and the AmpC β-lactamase was identified. The objective gene fragment was amplified by colonies PCR. The sequences of the PCR-products were analyzed. The DNA sequence of the structural gene ampC and the regulatory genes ampR, ampD and ampE was detected. The 6 strains and the wild-type Pseudomonas aeruginosa are highly homogeneous in structural and regulatory region. Some new mutant points were found. 展开更多
关键词 Pseudomonas aeruginosa Β-lactamase AmpC β-lactamase
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Detection of Beta-Lactamase and Extended-Spectrum Beta-Lactamase of Pathogens Isolated from Pig and Chicken and Their Antibiotic Susceptibility Test 被引量:1
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作者 HU Gong-zheng ZHANG Chun-hui +2 位作者 YUAN Li YANG Yu-rong LIANG Jun 《Agricultural Sciences in China》 CAS CSCD 2005年第11期877-882,共6页
The antibacterial activity of beta-lactam antibiotics or their combinations with inhibitor sulbactum against non-lactamase- producing strains, lactamase-producing and ESBLs-producing isolates was evaluated with twofol... The antibacterial activity of beta-lactam antibiotics or their combinations with inhibitor sulbactum against non-lactamase- producing strains, lactamase-producing and ESBLs-producing isolates was evaluated with twofold dilution method after pathogens isolated from pigs and chickens were detected, respectively, for beta-lactamase and extended-spectrum beta- lactamases (ESBLs), The results revealed that most of 43 clinically isolated strains could produce beta-lactamase and 3 strains of shigella isolated from chicken samples produced ESBLs. All of 30 lactamase-producing strains isolated and only one of 16 non-lactamase-producing strains were resistant to amoxicillin and ampicillin. MICs of ampicillin against lactamaseproducing isolates decreased 10-40 and 10-20 times respectively, when it was conbined with sulbactam at ration of 1:2 and 1:4. All clinical isolates were susceptible to third-generation cephalosporins. The MICs of third-generation cephalosporins against lactamase-producing isolates did not change when they were conbined with sulbactam. MICs of ceftiofur and ceftriaxone against ESBLs-producing isolates decreased 2-4 times when they were conbined with sulbactam. 展开更多
关键词 BETA-lactamase Extended-spectrum beta-lactamase INHIBITOR Antibiotic susceptibility test
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阿拉善-华北北缘晚古生代-早中生代岩浆作用:对古亚洲洋俯冲-闭合过程的制约
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作者 曾浩 宋东方 +1 位作者 肖文交 李普庆 《岩石学报》 SCIE EI CAS 北大核心 2025年第1期66-90,共25页
位于中亚造山带南部的阿拉善-华北北缘地区保存了丰富的晚古生代-早中生代岩浆记录,为理解古亚洲洋从俯冲至闭合的构造演化过程提供了关键信息。本文对位于内蒙古西部的甘其毛都地区的4个侵入体进行了岩相学、地球化学、锆石U-Pb年代学... 位于中亚造山带南部的阿拉善-华北北缘地区保存了丰富的晚古生代-早中生代岩浆记录,为理解古亚洲洋从俯冲至闭合的构造演化过程提供了关键信息。本文对位于内蒙古西部的甘其毛都地区的4个侵入体进行了岩相学、地球化学、锆石U-Pb年代学和Lu-Hf同位素分析。锆石U-Pb定年表明这些岩体分别形成于早二叠世(283±3Ma、273±5Ma、272±5Ma)和中三叠世(238±3Ma)。早二叠世岩体以石英闪长岩和闪长玢岩为主,富集轻稀土与大离子亲石元素,亏损高场强元素Nb、Ta等,Hf同位素显著亏损(-4.0~+15.6)。它们可能是由俯冲板片流体交代地幔楔部分熔融形成的基性岩浆经分离结晶演化而成。中三叠世侵入体为花岗闪长岩,轻重稀土元素强烈分异,锆石ε_(Hf)(t)值均为正值(+5.0~+8.5),可能代表了碰撞造山阶段新生下地壳物质部分熔融的产物。在此基础之上,本文系统收集并分析了阿拉善-华北北缘地区晚古生代-早中生代岩浆岩的时空分布规律与地球化学特征,以限定其构造背景与深部动力学过程。结合前人研究成果提出:石炭纪时期,古亚洲洋向南俯冲至阿拉善-华北克拉通之下并不断向北后撤;至早二叠世,俯冲板片转变为前进式俯冲,整体处于挤压环境,发育大规模岩浆活动与弧背前陆盆地;早-中三叠世,古亚洲洋闭合,阿拉善-华北克拉通沿索伦缝合带与北侧的中亚弧增生体系发生碰撞-拼贴。 展开更多
关键词 阿拉善 华北北缘 晚古生代-早中生代 古亚洲洋 俯冲-闭合
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Prevalence and characteristics of extended spectrum β-lactamase-producing Escherichia coli from bovine mastitis cases in China 被引量:2
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作者 YANG Feng ZHANG Shi-dong +4 位作者 SHANG Xiao-fei WANG Xu-rong WANG Ling YAN Zuo-ting LI Hong-sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第6期1246-1251,共6页
The aim of the study was to investigate the prevalence and characterization of extended-spectrum β-lactamase (ESBL)- producing Escherichia coli isolated from bovine mastitis cases in China. ChromID ESBL agar was us... The aim of the study was to investigate the prevalence and characterization of extended-spectrum β-lactamase (ESBL)- producing Escherichia coli isolated from bovine mastitis cases in China. ChromID ESBL agar was used to confirm ESBL-producing E. coli. PCR and DNA sequencing were employed to characterize the genotype of ESBL-producers. Antimicrobial susceptibility was measured by disc diffusion. Overall, 73 of 318 E. coli isolates (22.96%) were identified as ESBL-producers. Of these ESBL-producing E. coli, the prevalence of blaCTX-M and blaTEM-1 was 97.26 and 71.23%, respectively. The predominant CTX-M-type ESBL was CTX-M-15 (65.75%), followed by CTX-M-14 (10.96%), CTX-M-55 (9.59%), CTX-M-64 (5.48%), CTX-M-65 (4.11%) and CTX-M-3 (1.37%). This study is the first report of CTX-M-64 and CTX-M-65 in E. coli isolated from bovine mastitis. Furthermore, 72 ESBL-producing E. coli isolates (98.63%) were found to be multidrug-resistance. This study noted high prevalence and rates of antimicrobial resistance of ESBL-producing E. coli isolates from bovine mastitis cases in China. 展开更多
关键词 extended spectrum β-lactamase Escherichia coli MULTIDRUG-RESISTANCE bovine mastitis
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Antimicrobial Resistance and Genotype Analysis of Extended-Spectrum-β-Lactamase-Producing Proteus Mirabilis 被引量:2
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作者 Ying Huang Yuanhong Xu +1 位作者 Zhongxin Wang Xianghong Lin 《Open Journal of Clinical Diagnostics》 2014年第1期57-62,共6页
To analyse the genotypes of clinical isolates of Extended-Spectrum-β-Lactamase-Producing (ESBL-producing) Proteus mirabilis (P. mirabilis) and the mechanisms of antimicrobial resistance, to guide reasonable use of an... To analyse the genotypes of clinical isolates of Extended-Spectrum-β-Lactamase-Producing (ESBL-producing) Proteus mirabilis (P. mirabilis) and the mechanisms of antimicrobial resistance, to guide reasonable use of antibiotics and to avoid nosocomial outbreak infections by ESBL-producing P. mirabilis. 125 clinical isolates of P. mirabilis were collected from the Drug-Resistant Bacteria Surveillance Center of Anhui Province (from Jan 2009 to May 2010). Searching for the genotypes of ESBLs was perfomed by PCR amplification and DNA sequencing, and performed conjugation test simultaneously. Among ESBL-producing strains, CTX-M was the major genotype (3 CTX-M-13 and 1 CTX-M-3). TEM-1b spectrum β-lactamase was also prevalence in P. mirabilis. The diversity of β-lactamases in P. mirabilis and the emergency of multi-drug-resistance clinical strains will present serious threat to clinical therapy and even will lead to outbreak of nosocomial infections. Our study emphasizes the need for enhanced supervision of ESBL-producing P. mirabilis. Timely and reasonable drug-resistance data are indispensable to clinical therapy. 展开更多
关键词 GENOTYPE Extended-Spectrum-β-lactamase ANTIMICROBIAL Resistance PROTEUS Mirabilis
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气相色谱-离子迁移谱技术在食品真实性鉴别中的应用研究进展
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作者 张碧莹 隋雨萌 +4 位作者 张鑫 李永杰 孔保华 刘昊天 陈倩 《食品科学》 EI CAS 北大核心 2025年第1期227-236,共10页
气相色谱-离子迁移谱是一种灵敏的检测、鉴别和监测不同基质中痕量物质的分析技术,能够通过气相色谱和离子迁移谱对分析物质进行二次快速分离和高精准定性。由于气相色谱-离子迁移谱具有环保、使用便捷、操作简单及适用于工业大量连续... 气相色谱-离子迁移谱是一种灵敏的检测、鉴别和监测不同基质中痕量物质的分析技术,能够通过气相色谱和离子迁移谱对分析物质进行二次快速分离和高精准定性。由于气相色谱-离子迁移谱具有环保、使用便捷、操作简单及适用于工业大量连续检测等优点,近年来逐渐成为食品真实性鉴别的热门分析技术。本文主要介绍气相色谱-离子迁移谱的类型、结构、工作原理和分析方法,重点综述其在食品真实性鉴别中的应用,以期为食品真实性问题的解决提供理论参考。 展开更多
关键词 气相色谱-离子迁移谱 真实性鉴别 食品 应用
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α-亚麻酸通过TLR4/MyD88/NF-κB信号通路抑制脂多糖诱导的巨噬细胞炎症
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作者 蔡瑞鑫 陈小蝶 +3 位作者 朱海彬 钱雨顺 谢建华 申明月 《食品工业科技》 CAS 北大核心 2025年第1期377-383,共7页
ω-3脂肪酸具有自然的抗炎属性,而α-亚麻酸(ALA)是一种人体必需的ω-3脂肪酸,为了阐明其体外抗炎机制,本实验采用脂多糖(LPS)刺激巨噬细胞构建炎症模型,通过测定单核细胞趋化蛋白(MCP-1)、白细胞介素4(IL-4)、白细胞介素13(IL-13)等炎... ω-3脂肪酸具有自然的抗炎属性,而α-亚麻酸(ALA)是一种人体必需的ω-3脂肪酸,为了阐明其体外抗炎机制,本实验采用脂多糖(LPS)刺激巨噬细胞构建炎症模型,通过测定单核细胞趋化蛋白(MCP-1)、白细胞介素4(IL-4)、白细胞介素13(IL-13)等炎症因子的水平、活性氧(ROS)生成量和炎症信号通路相关蛋白表达情况探讨α-亚麻酸减轻脂多糖诱导的炎症反应的机制。结果表明,α-亚麻酸能显著抑制MCP-1的释放,提高抗炎细胞因子IL-13的分泌水平;同时,α-亚麻酸还可以降低ROS生成量,缓解ROS介导的炎性损伤。此外,α-亚麻酸可以通过增加抗氧化酶SOD的表达,减少MDA的堆积,从而减轻炎症反应中氧化应激的伴随性危害。蛋白印迹分析进一步证实,α-亚麻酸可抑制TLR4、MyD88的表达以及下游p65和IκBα的磷酸化水平。以上结果表明,α-亚麻酸可明显抑制LPS诱导的RAW264.7细胞炎症反应,其机制可能与抑制TLR4/MyD88/NF-κB信号通路激活有关。 展开更多
关键词 Α-亚麻酸 巨噬细胞 炎症 信号通路
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Appendical Perforation by Infection with Extended-Spectrum Beta-Lactamase (ESBL)-Producing <i>Escherichia coli</i>: Case Report 被引量:1
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作者 Hisayuki Miyagi Tadao Okada +2 位作者 Shohei Honda Masashi Minato Akinobu Taketomi 《Surgical Science》 2012年第1期53-55,共3页
We report the very rare case of a huge appendical abscess with extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli) as the pathogen. There have been several reports of appendical infections suc... We report the very rare case of a huge appendical abscess with extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli) as the pathogen. There have been several reports of appendical infections such as appendicitis and appendical abscess caused by ESBL-producing bacteria in adults. The treatment of ESBL-producing E. coli infection is specific, and ESBL-producing bacteria have recently been reported as pathogens associated appendicitis in children. To the best of our knowledge, this is the second report of perforated appendicitis with abscess due to ESBL-producing E. coli. We discuss the diagnostic modalities and treatments for appendical abscess with ESBL-producing E. coli. and propose that the patients with perforated appendicitis and abscess formation due to ESBL-producing E. coli should be administered the antibiotic MEPM within 2 weeks to treat the abscess more effec-tively without producing other multidrug-resistant bacteria. 展开更多
关键词 APPENDICITIS ESBL (Extended-Spectrum Beta-lactamase)-Producing E. coli Abscess MEROPENEM
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