志贺菌敏感株与诱导耐多药株蛋白质组学分析

目的对志贺菌敏感株与诱导耐多药株全菌蛋白进行蛋白质组学比较，寻找细菌耐多药相关蛋白。方法采用4类抗生素的次抑菌浓度，对临床分离鉴定的志贺菌敏感株进行诱导耐多药试验；对志贺菌敏感株及诱导耐多药株全菌蛋白进行双向电泳；电泳图谱采用ImageMaster2DPlatinum软件分析；差异表达蛋白进行基质辅助激光解吸飞行时间质谱（MOLDITOF-TOF质谱）分析。结果成功获得志贺菌诱导耐多药株，在志贺菌敏感株与耐多药株全菌蛋白质图谱中分别检测出（946±37）个和（1096±189）个蛋白质斑点；共发现48个差异表达的蛋白点，其中5个质谱鉴定为ABC转运蛋白、谷胺酰转肽酶、天冬氨酸氨甲酰基转移酶、翻译延长因子Tu、单链DNA结合蛋白；其中前3个蛋白中在耐多药株中表达量增强，后2个减弱。结论5个耐多药相关蛋白中在细胞代谢中起重要作用的酶类表达量上调；ABC转运蛋白在志贺菌诱导耐多药机制中起重要作用。     

志贺菌耐多药相关基因水平转移研究

目的 验证志贺菌耐多药相关基因水平转移及对该基因的位置进行初步判定.方法 培养已筛选出的包含耐多药差异基因片段阳性克隆,提取其质粒,PCR扩增其耐多药差异基因片段、纯化、制备探针,与志贺菌敏感株Z23、耐多药大肠埃希菌E.667、转移株的基因组DNA、质粒进行斑点杂交.结果 该耐多药差异基因片段制备的探针与耐多药大肠埃希菌、敏感株、转移株的基因组DNA、质粒进行杂交后,转移株、耐多药大肠埃希菌的全基因组及质粒均有杂交信号,与Z23的全基因组、质粒均没有杂交信号.结论 此耐多药相关基因片段在液体结合实验中由耐多药大肠埃希菌水平转移给志贺菌敏感株,根据斑点杂交结果可判断其存在于耐多药大肠埃希菌和转移株的质粒中.     

志贺菌敏感株诱导耐药与marOR基因突变关系

目的对志贺菌敏感株进行诱导使其耐多药,研究其诱导耐药前后marOR基因的差异。方法用4类抗生素的次抑菌浓度对临床分离鉴定的志贺菌敏感株进行诱导耐多药试验。对志贺菌敏感株及诱导耐多药株的marOR基因进行聚合酶链反应(PCR)扩增后,测序比较其诱导耐药前后marOR基因序列的差异。结果成功获得志贺菌诱导耐多药株,命名为YD株;其最小抑菌浓度(MIC)分别为初始菌株的6～8倍;该诱导耐药株对庆大霉素、诺氟沙星、磺胺甲基异恶唑、头孢噻吩等均耐药;测序结果发现诱导耐药株marOR基因YD株有6个位点出现突变,其中5个为同义突变,1个为错义突变(1630位点A→G,赖氨酸→精氨酸)。结论 marOR基因的突变可能是志贺菌诱导耐药的调控机制之一。     

志贺菌诱导耐药相关基因序列分析

目的获取并分析志贺菌由抗生素诱导产生的耐多药相关基因序列。方法以志贺菌敏感株(Z23)和诱导株(YD)基因组DNA为模板,利用引物设计软件Primer 5.0根据已测得基因序列(Y16B3、Y16B8和Y16A11)设计引物,PCR扩增诱导耐多药相关基因并将相关基因克隆到pMD19-T载体上,测序并将结果在序列相似性搜索工具Blast上检索分析相关基因序列。结果Y16B3和Y16B8基因片段分别在诱导株中扩增出320和225 bp产物,在敏感株中未扩增出;而Y16A11基因片段在诱导株扩增出310 bp产物,在敏感株中扩增出554 bp产物,并且产物序列同源性极低。结论志贺菌在抗生素诱导下产生的耐多药株与敏感菌株比较,具有基因组差异。     

志贺菌临床分离株耐多药与调控基因突变关系

目的 研究志贺菌的耐多药性及其耐多药调控基因acrR、marOR的变异性.方法 对56株临床分离的志贺菌进行四环素、氯霉素、氨苄青霉素、环丙沙星、诺氟沙星等5种药物的药敏试验,对其acrR、marOR基因进行聚合酶链反应(PCR)扩增后,TaqI限制性内切酶酶切与单链构象多态性(SSCP)分析.结果 筛选出35株耐多药株与11株敏感野生株.56株临床分离的志贺菌属细菌的耐多药率为62.5%;35株耐多药株与11株敏感野生株均扩增出acrR、marOR基因,未发现基因缺失株;单链构象多态性分析发现,acrR基因突变率为6.52%,marOR基因突变率为10.87%,11株敏感野生株均未检出以上2种基因突变.结论 志贺菌耐多药率较高,acrR、marOR基因突变可能是其耐多药的调控机制之一.     

耐多药结核杆菌与药物敏感菌株蛋白质比较

目的 比较结核分支杆菌耐多药菌株与药物敏感菌株在蛋白表达水平的差异,为进一步研究结核杆菌耐药的分子调控机制提供依据.方法 利用双向聚丙烯酰胺凝胶电泳(2-DE)分离耐多药结核分支杆菌和结核分支杆菌药物敏感菌株总蛋白质,通过计算机图像分析软件比较分析电泳图谱,切取部分差异蛋白质点进行肽质量指纹图谱分析.结果 发现27个蛋白质点具有明显差异,其中耐多药结核分支杆菌有6个蛋白质点明显表达上调.质谱分析发现,6个蛋白质点分别代表的蛋白质为无机焦磷酸酶、多肽脯氨酰基顺反同分异构酶A、延伸因子Tu、420个氨基酸的未知功能蛋白质、双加氧酶和转录调节蛋白(MoxR).结论 耐多药结核杆菌与药物敏感菌株在蛋白表达水平存在明显差异.     

福建省耐多药结核分枝杆菌相关耐药基因突变特征分析

目的分析福建省耐多药结核分枝杆菌耐药相关基因rpoB、katG和rpsL的突变特征,为建立快速分子药敏方法提供科学依据。方法收集监测点的痰培养分离菌株进行菌种鉴定、药物敏感性试验。选取46株耐多药结核分枝杆菌和15株全敏感株,扩增rpoB、katG和rpsL的基因片段,测序,比对分析。结果全敏感株rpoB和rpsL基因未检测到突变。耐多药菌株rpoB、katG和rpsL基因的突变率分别为91.30%,80.43%,30.43%。耐多药菌株三个基因的突变率均高于全敏感株的突变率,差异均有统计学意义(χ2值分别为46.67,4.29和11.58,P均<0.05)。katG、rpoB基因同时存在突变的耐多药菌株占80.43%,三个耐药基因均有突变的耐多药菌株占30.43%。结论福建省耐多药结核分枝杆菌的常见突变位点为rpoB531和rpoB526,katG315,rpsL43。     

活性非可培养状态痢疾志贺菌蛋白分析研究

目的研究处于活性非可培养状态（VBNC状态）的痢疾志贺菌血清1型蛋白表达情况。方法将低温寡营养诱导处于VBNC状态与处于对数生长期的痢疾志贺菌血清型1型全蛋白提取，用2D电泳将蛋白质分开，TOF／TOF二级质谱鉴定差异蛋白。结果共获得14个差异点，11个为酶，3个为具有酶活性的蛋白，这些蛋白质可调节细菌的能量代谢和物质合成。处于VBNC状态的痢疾志贺菌保持较高水平的代谢活性，有氧氧化和底物水平磷酸化水平较高，但是细菌蛋白表达能力下降，分裂能力下降。结论从蛋白水平证实了处于VBNC状态的痢疾志贺茵有活性，并解释了难于在常规培养基上形成茵落的原因。     

福建省46株耐多药结核分枝杆菌katG基因突变特征研究

目的:了解福建省耐多药结核分枝杆菌临床分离株katG基因的突变特点,为建立适合我省快速检测异烟肼耐药方法提供参考。方法:对福建省9个监测点进行耐药性调查,收集菌株经菌种鉴定、药物敏感性试验。选取46株耐多药结核分枝杆菌和15株全敏感株,扩增katG高突变区域的基因片段,测序后比对分析。结果:15株全敏感株未检测氨基酸突变。46株耐多药结核分枝杆菌katG基因的突变率为80.43%,katG 315的突变率为54.35%,联合突变率为52.17%。结论:福建省耐多药结核分枝杆菌杆不同耐药谱katG基因突变率不同,最常见的点突变发生于315位,463位具有等位基因多态性。     

志贺菌属非典型1类整合子与耐多药关系

目的研究志贺菌属中非典型1类整合子的分布及其与耐多药性的关系。方法对实验室保存的90株志贺菌属进行8种抗生素药敏实验,针对非典型1类整合子的耐药基因盒区域设计引物进行聚合酶链反应(PCR)扩增和限制性片段长度多态性(RFLP)分析,对代表性菌株进行测序分析。结果 90株志贺菌属中有86株(95.6%)对≥3种抗生素耐药;有66株(73.3%)对氨苄青霉素(AMP)、四环素(TET)和氯霉素(CHL)联合耐药;非典型1类整合子分布于65株(72.2%)志贺菌属中;RFLP分析结果表明,所有酶切产物的带型均一,测序分析发现序列为blaoxa-30-aadA1;非典型1类整合子阳性菌株对AMP-TET-CHL联合耐药率(81.5%)高于阴性菌株(52.0%),经双侧χ2检验发现差异有统计学意义(P<0.05)。结论志贺菌属非典型1类整合子阳性与其对AMP-TET-CHL联合耐药有关,可能参与耐多药性的形成。     

The trucker strain monitor: an occupation-specific questionnaire measuring psychological job strain

Objectives: To develop and validate a short and user-friendly questionnaire measuring psychological job strain in truck drivers. Methods: In cooperation with an occupational physician in the Dutch road transport industry we developed items on the basis of face validity and information of existing questionnaires on the subject. These items were pilot-tested, by means of interviews, in 15 truck drivers. Study I examined the factorial structure of the initial 30-item trucker strain monitor (TSM) in a sample of 153 truck drivers. Subsequently, number of items per factor was reduced on the basis of reliability analyses (Cronbach's alpha). Study II examined construct and criterion validity of the TSM in a randomly selected group of 2,000 truck drivers, of whom 1,111 participated (adjusted response=63%). Additionally, sensitivity and specificity were assessed by examining the ability of the TSM to identify truck drivers with or without self-reported sickness absence in the past 12 months because of psychological complaints. Results: Factor analyses of the initial 30-item TSM revealed a two-factor solution. Item reduction resulted in a six-item work-related fatigue scale and four-item sleeping problems scale with high internal consistency. Results of study II confirmed the internal consistency of the TSM scales and provided support for construct and criterion validity. The composite, work-related fatigue, and sleeping problems scale had a sensitivity of 83%, 80% and 71% respectively, in identifying truck drivers with prior sickness absence because of psychological complaints. Specificity rates were 72%, 73% and 72% respectively. Conclusion: Despite methodological limitations, the results suggest that the TSM is a reliable and valid indicator of psychological job strain in truck drivers. In particular, the composite and work-related fatigue scale identified drivers with prior absenteeism because of psychological complaints, quite accurately. Future longitudinal research in specific sub-groups of truck drivers including both self-reported and objective psychological health measures should evidence whether (1) the distinction between two indicators of psychological job strain is useful, and whether (2) the TSM can be used in screening out truck drivers at risk of developing psychological health problems. Received: 20 July 2000 / Accepted: 30 March 2001     

Heat strain in cold

In spite of increased environmental cold stress, heat strain is possible also in a cold environment. The body heat balance depends on three factors: environmental thermal conditions, metabolic heat production and thermal insulation of clothing and other protective garments. As physical exercise may increase metabolic heat production from rest values by ten times or even more, the required thermal insulation of clothing may vary accordingly. However, in most outdoor work, and often in indoor cold work, too, the thermal insulation of clothing is impractical, difficult or impossible to adjust according to the changes in physical activity. This is especially true with whole body covering garments like chemical protective clothing. As a result of this imbalance, heat strain may develop. In cold all the signs of heat strain (core temperature above 38 degrees C, warm or hot thermal sensations, increased cutaneous circulation and sweating) may not be present at the same time. Heat strain in cold may be whole body heat strain or related only to torso or core temperature. Together with heat strain in torso or body core, there can be at the same time even cold strain in peripheral parts and/or superficial layers of the body. In cold environment both the preservation of insulation and facilitation of heat loss are important. Development of clothing design is still needed to allow easy adjustments of thermal insulation.     

猪种布鲁氏菌生物1型野毒株和2号菌苗的鉴别诊断

目的寻找猪种布鲁氏菌生物1型野毒株（1330S）和猪种布鲁氏菌2号菌株（S2）的鉴别诊断方法。方法采用牛、羊、绵羊、猪种型聚合酶链反应（AMOS—PCR）、脉冲场凝胶电泳（PFGE）和多位点可变数量串联重复序列（MLVA）3种方法对21株1330S菌株进行鉴别？结果AMOS—PCR和PFGE方法未能区分两类菌株;MLVA方法发现1330S和S2菌株在Bru9和Bru16两位点存在差异。结论MLVA方法可以作为两类菌株鉴别诊断的方法之一。