耐碳青霉烯类肺炎克雷伯菌的耐药基因分析

目的 了解铜陵市人民医院分离的碳青霉烯类耐药肺炎克雷伯菌（CRKP）的耐药基因型。方法 收集2011年5月至2016年8月铜陵市人民医院临床标本中分离的CRKP,采用VITEK-2 Compact全自动微生物鉴定仪进行鉴定,改良Hodge试验检测碳青霉烯酶表型,聚合酶链反应（PCR）检测碳青霉烯酶基因（bla_KPC、bla_IMP、bla_VIM、bla_NDM和bla_OXA-48）,并对各碳青霉烯酶基因阳性扩增产物进行基因测序。结果 共收集CRKP 90株,其中改良Hodge试验阳性84株（93.3%）,51株（56.7%）携带bla_KPC-2基因,2株（2.2%）携带bla_IMP-4基因,1株（1.1%）携带bla_VIM-1基因。结论 该院肺炎克雷伯菌对碳青霉烯类抗菌药物的主要耐药机制是产KPC-2型碳青霉烯酶。     

我院肠杆菌科细菌对碳青霉烯类抗菌药物的耐药性分析

目的:探讨我院肠杆菌科细菌对碳青霉烯类抗菌药物的耐药性。方法:收集我院2014年1-4月分离的肠杆菌科细菌404株,分析其标本分布,选取57株对亚胺培南(IMI)或厄他培南(ETP)最低抑菌浓度(MIC)≥2μg/ml中介或耐药的肠杆菌科细菌,采用改良Hodge试验检测其碳青霉烯酶(KPC),纸片扩散法(K-B)检测其对美罗培南(MPN)的敏感性(抑菌环直径)。结果:57株肠杆菌科细菌对IMI敏感率为88.9%,对ETP敏感率为96.0%,对MPN敏感率为99.3%;8株细菌改良Hodge试验阳性。结论:对碳青霉烯类抗菌药物耐药的肠杆菌科细菌数量和种类检出率较高,应引起临床高度重视。     

碳青霉烯耐药肠杆菌科细菌的耐药机制探讨

目的探讨本院存在的碳青霉烯类耐药肠杆菌科细菌的耐药机制。方法临床检出碳青霉烯类抗菌药物非敏感肠杆菌科细菌6株。改良Hodge实验、EDTA协同试验检、改良三维实验检测其耐药表型;引物特异性PCR法检测其碳青霉烯酶耐药基因及外膜蛋白基因存在情况。结果 1株大肠埃希菌中改良Hodge实验弱阳性,EDTA协同试验阳性,改良三维实验结果可被CLA单独抑制,PCR扩增结果IMP4碳青霉烯酶基因阳性。5株产气肠杆菌改良Hodge实验,阴性3株,阳性两株,EDTA协同试验阴性;改良三维实验中,5株均可被CLO+CLA混合液完全抑制,PCR未扩增出目的基因条带和膜蛋白基因。结论本地区大肠埃希菌的耐药机制可能与IMP4型金属碳青霉烯酶存在有关,产气肠杆菌耐药机制可能与ESBLs和AmpC酶同时存在、膜蛋白表达缺失及其他未检测到的碳青霉稀酶存在有关。     

我院肠杆菌科细菌对碳青霉烯类抗菌药物的耐药性分析

目的:为临床合理使用碳青霉烯类抗菌药物提供参考。方法:收集我院2014年1月-2015年12月检出的肠杆菌科细菌,采用半自动微生物测定仪进行菌株培养、鉴定及药敏试验,采用改良Hodge试验和纸片扩散法进行产肺炎克雷伯菌碳青霉烯酶(KPC)和产超广谱β-内酰胺酶(ESBLs)耐药菌株的确证。结果:我院2014-2015年共检出肠杆菌科细菌1035株,其中大肠埃希菌732株,肺炎克雷伯菌157株、阴沟肠杆菌136株、黏质沙雷菌10株,未检出枸橼酸杆菌。大肠埃希菌和肺炎克雷伯菌对阿米卡星和碳青霉烯类抗菌药物的敏感率较高,而对大部分头孢菌素类抗菌药物的敏感率较低。共检出耐碳青霉烯类肠杆菌科细菌64株(6.18%),其中耐碳青霉烯类大肠埃希菌31株(4.23%)、耐碳青霉烯类肺炎克雷伯菌30株(19.11%)、耐碳青霉烯类阴沟肠杆菌1株(0.74%)、耐碳青霉烯类黏质沙雷菌2株(20.00%);耐药菌株主要来源于痰液和尿液标本,且主要集中于新生儿内科和重症医学科。64株耐药菌株中,产KPC的有59株(92.19%)、产ESBLs的有3株(4.69%)。结论:我院肠杆菌科细菌以大肠埃希菌为主,且耐碳青霉烯类大肠埃希菌和耐碳青霉烯类肺炎克雷伯菌的检出数量较多。肠杆菌科细菌对碳青霉烯类抗菌药物的耐药性可能与其产KPC和ESBLs有关。临床应遵循用药指征,结合药敏试验结果合理选用碳青霉烯类抗菌药物。     

对碳青霉烯类抗菌药不敏感肠杆菌科细菌耐药性分析

目的:了解我院临床分离的对碳青霉烯类抗菌药不敏感的肠杆菌科细菌对常用抗菌药物的耐药性。方法:收集2013年4月-2014年3月我院临床分离的30株对碳青霉烯类抗菌药不敏感的肠杆菌科细菌,使用由美国BD公司生产的Phoenix-100全自动细菌鉴定/药敏系统进行菌株鉴定和药敏试验,产碳青霉烯酶的表型确证采用改良Hodge试验。结果:30株对碳青霉烯类抗菌药不敏感的肠杆菌科细菌对多黏菌素、阿米卡星和复方新诺明的敏感率较高,依次为100.0%,73.3%和66.7%;对碳青霉烯类抗菌药亚胺培南和美罗培南的耐药率分别为100.0%和86.7%;对氨苄西林、头孢菌素类、含β-内酰胺酶抑制剂的复合制剂和单环β-内酰胺类抗菌药的耐药率均为100.0%;对其余抗菌药的耐药率均在60.0%以上。30株菌的改良Hodge试验阳性率为86.7%(26/30)。结论:对碳青霉烯类抗菌药不敏感的肠杆菌科细菌对常用抗菌药物表现为高度多重耐药,为高产碳青霉烯酶菌株。为防止产碳青霉烯酶基因的流行,临床应合理使用抗菌药物并加强对肠杆菌科细菌产碳青霉烯酶的监测。     

用改良Hodge试验检测产碳青霉烯酶肠杆菌科细菌

目的了解分离的肠杆菌科细菌产碳青霉烯酶情况,为临床正确选择抗菌药物提供依据。方法采用K-B纸片扩散法检测并筛选厄他培南和美罗培南,以抑菌环直径分别为19~21 mm和16~21 mm的菌株作为待测菌,进行改良的Hodge试验。结果 390株肠杆菌科细菌中筛选出55株可疑产碳青霉烯酶菌株,对可疑菌株进行改良的Hodge试验,阳性率21.82%(12/55)。结论碳青霉烯类抗生素敏感折点附近的肠杆菌科细菌有近1/5菌株产碳青霉烯酶,临床微生物学实验室应执行改良Hodge试验,以确保药敏试验结果的准确性。     

肺炎克雷伯菌及大肠埃希菌产KPC酶的检测研究

目的了解肺炎克雷伯菌及大肠埃希菌产KPC酶的情况和耐药关系。方法收集2007年3月至2008年10月临床分离的肺炎克雷伯菌及大肠埃希菌681株,采用KB纸片法进行药敏试验,以亚胺培南,美罗培南,厄他培南为检测药物,筛选出碳青霉烯类耐药菌株,采用改良的Hodge试验、聚合酶链反应（PCR）扩增检测细菌产KPC酶及基因分型。结果在491大肠埃希菌株和190肺炎克雷伯菌株中,对碳青霉烯类耐药的大肠埃希菌6株,肺炎克雷伯杆菌6株。进行Hodge试验,12株菌全部阴性,聚合酶链反应（PCR）扩增没出现目的基因片段。结论在12株对碳青霉烯类抗生素耐药的细菌中未发现产KPC酶的菌株。据国内的同类研究报道,目前我国主要以产KPC-2酶为主,而且产KPC酶存在地域性差异,课题研究显示本区域暂时没发现产KPC酶的菌株,有待进一步监测研究。     

肠杆菌科细菌3年耐药性监测

目的了解我院2008年—2010年间临床常见肠杆菌科细菌的耐药情况及研究耐碳青霉烯类大肠埃希菌碳青霉烯酶基因型,为临床合理使用抗菌药物提供依据。方法收集我院2008-2010年间临床分离的常见肠杆菌科细菌,药敏试验使用纸片扩散法,数据分析采用WHONET5.4软件;筛选出对碳青霉烯类耐药的大肠埃希菌进行碳青霉烯酶基因的PCR检测及基因序列分析。结果 3年分离病原株共4916株,肠杆菌科共1980株,其中列前三位的是大肠埃希菌(873/1980),克雷伯菌属(605/1980)及肠杆菌属(268/1980),其次为变形菌属和沙雷菌属。主要来源于痰液、尿液及分泌物、血液、脓液等。重要肠杆菌科细菌对碳青霉烯类耐药率均小于10%,对头孢哌酮/舒巴坦、阿米卡星、哌拉西林/三唑巴坦者<30%,对广谱青霉素类及头孢菌素类者为40.9%～98.7%。变形菌属除对氨苄西林的耐药率>75%外,对其余抗生素的耐药率均低于40%,。3年来产超广谱β-内酰胺酶大肠埃希菌为33.97%及肺炎克雷伯菌57.50%,对大多数抗生素的耐药率显著高于非ELSBs菌株,且呈多重耐药。3年耐碳青霉烯类的大肠埃希菌共23株,其中产碳青霉烯酶者2株,PCR检测基因型阴性。结论本院肠杆菌科细菌大肠埃希菌和肺炎克雷伯菌检出率较高,碳青霉烯类对肠杆菌科细菌的抗菌活性最高,产ESBLs肠杆菌的耐药严重,实验室应加强对产ESBLs细菌的监测与报告。未检测出我院大肠埃希菌碳青霉烯酶基因型。治疗肠杆菌科细菌感染可选择碳青霉烯类,哌拉西林/三唑巴坦,头孢哌酮/舒巴坦,阿米卡星。     

卫生部全国细菌耐药监测网2011年度肠杆菌科细菌耐药监测

目的 了解2011年度我国临床分离肠杆菌科细菌对临床常用抗菌药物的耐药性.方法 全国149家医院收集临床肠杆菌科细菌,并进行药物敏感性测试,依照美国实验室与标准化研究所(CLSI)2011标准判断敏感性;用WHONET5.6软件处理分析.结果 共收集肠杆菌科细菌134296株.前3位分离菌依次为大肠埃希菌(60567株,占45.1％)、肺炎克雷伯菌(38834株,28.9％)和阴沟肠杆菌(11404株,8.5％).敏感性最高的抗菌药物为碳青霉烯类,除产酸克雷伯菌、产气肠杆菌和弗劳地枸橼酸杆菌对碳青霉烯类抗生素的耐药率在5％以上外;其他肠杆菌科细菌对碳青霉烯类抗生素的耐药率都约在4％或以下.结论 肠杆菌科细菌对各类抗菌药物呈现不同程度耐药,有些具多重耐药特点.碳青霉烯类仍是肠杆菌科细菌最敏感的药物,但已出现碳青霉烯耐药菌,应引起重视.     

碳青霉烯类耐药大肠埃希菌耐药基因型检测及同源性分析

目的检测临床分离碳青霉烯类耐药大肠埃希菌的耐药基因型,并对其同源性进行分析,研究其流行情况。方法收集铜陵市人民医院 2012年 9月至 2016年 10月临床分离碳青霉烯类耐药大肠埃希菌,采用 VITEK?2 Compact全自动微生物鉴定仪进行鉴定,改良 Hodge试验检测碳青霉烯酶表型, EDTA双纸片协同试验进行金属酶初筛,聚合酶链反应( PCR)检测碳青霉烯酶基因( blaKPC、blaIMP、blaVIM、blaNDM和 blaOXA?48)并对阳性扩增产物进行基因测序;同源性分析采用肠杆菌科基因间重复一致序列聚合酶链反应技术( ERIC?PCR)。结果共收,集碳青霉烯类耐药大肠埃希菌 25株, 8株改良 Hodge试验阳性, 13株金属酶初筛试验阳性,其中 4株携带 blaNDM?1基因, 1株携带 blaIMP?4基因, 1株携带 blaKPC?2基因; ERIC?PCR检测分为 10种型别。结论碳青霉烯类耐药大肠埃希菌的耐药机制主要是产金属酶,携带 NDM?1型碳青霉烯酶大肠埃希菌需重点监测;碳青霉烯类耐药大肠埃希菌未在医院引起克隆流行。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.