目的 探讨神经氪酸酶基因A（nanA）产物对感染肺炎球菌后仓鼠咽鼓管细胞表面糖化合物变化的作用。方法应用植物血凝索组织化学技术，比较仓鼠在感染肺炎球菌（D39菌株）及其神经氨酸酶基因A缺陷株（△NAl）后咽鼓管细胞表面糖化合物的变化。结果 植物血凝素标记结果显示，D39感染组咽鼓管上皮细胞的LFA和SNA的染色比非感染对照组有明显下降，提示正常求端涎酸残基在D39组已被祛除，同时，咽鼓管腔表面WGA，SuccWGA，BSL-H，PNA和FCL在D39感染组的染色增强，而神经氨酸酶基因陋就简A缺陷株（△NAl）感染组与非感染对照组相比，植物血凝索标记染色结果差异无显著性。结论 神经氨酸酶基因A（nanA）产物在改变细胞表面糖化合物结构的作用中起重要作用，由此导致肺炎球菌在仓鼠咽鼓管的种植和感染。

Between 24 July and 31 August 1998, thousands of domestic pigs died of hemorrhagic shock in three adjunct counties along the YangZi River in Jiangshu Province, China. From 28 July to 6 September 1998, 40 local farmers (36 males and 4 females, ages 23 to 78 years) were hospitalized with severe illness characterized by high fever, erythematous rash or petechiae, and profound lethargy after contact with sick pigs. Twelve (30%) of these patients died of respiratory failure and shock. Eleven bacterial isolates recovered from 11 blood and cerebrospinal fluid specimens collected from seven patients and two pigs were identified as Enterococcus faecium based on biochemical reactions and 16S rRNA gene sequence analysis. Both pig and human E. faecium isolates displayed indistinguishable antibiotic susceptibility and pulsed-field gel electrophoresis patterns. These data strongly suggest the spread of an outbreak of E. faecium-related sepsis from pigs to humans.

Objetlve To explore the effect of products of nan A gene on the changes of cell surface carbohydrates of the chinchilla eustachian tube after infection with Streptococcus pneumonide. Methods Using leetin histachemieal techique to compare the changes of the cell surface carbohydrates in the chinchilla eustachian tube afler infection with S. pneumoniae D39 or ANAI mutant. Results The labeling pattern revealed that the staining with Limax favus agglutinin (LFA) and Sambucus nigra agglutinin (SNA) Was decreased in epithelium of the eustachian tube in the D39 cohort cnmpared to the uninfected control. which indicated that the normal terminal sialic acid residue were removed. Cnncurrently, the increased staining with wheat germ agglutinin (WGA). sueeinylated wheat germ agglutinin (Suce WGA). Bandeiraea simplicfolia leetin II (BSL-II). peanut agglutinin (PNA) and Erythrina cristagalli lectin (ECL) was observed in the lumen surface of eustachian tube subsequent to intranasal inoculation with D39. HowevES. the ANAl neuraminidase deficient mutant did not show any significant changes in the lectin labeling Patterns as compared with those of the eontnfl cohort. Conclnskms The products of the nan A gene play an important role in the changes of cell surface catrbohydrates and thus may be respnnsible for the eohmization in the chinchilla eustachian tube after infection with Streptococcus pneumoniae.

Between 24 July and 31 August 1998, thousands of domestic pigs died of hemorrhagic shock in three adjunct counties along the YangZi River in Jiangshu Province, China. From 28 July to 6 September 1998, 40 local farmers (36 males and 4 females, ages 23 to 78 years) were hospitalized with severe illness characterized by high fever, erythematous rash or petechiae, and profound lethargy after contact with sick pigs. Twelve (30%) of these patients died of respiratory failure and shock. Eleven bacterial isolates recovered from 11 blood and cerebrospinal fluid specimens collected from seven patients and two pigs were identified as Enterococcus faecium based on biochemical reactions and 16S rRNA gene sequence analysis. Both pig and human E. faecium isolates displayed indistinguishable antibiotic susceptibility and pulsed-field gel electrophoresis patterns. These data strongly suggest the spread of an outbreak of E. faecium-related sepsis from pigs to humans.

目的 观察病毒血症在病路各期的变化。方法 根据汉坦病毒血清Ⅰ型76-118株及血清Ⅱ型80-39株M基因G1区设计两面三刀对公有引物及一条探针，应用RT-nestedPCRyy方法对57例96份肾综合征出血热（HFRS）患者血清中HV-RNA检测测，所PCR产物用DOT-Blot证实。结果 96份样本中68份阳性，阳性率70.8%；在病程第1、2、3、周，HV-RNA检测率分别分94.7%、47.5%、25%，P<0.05；重型病人持续2周HV-RNA阳性检测率100%，而轻、中型分别为12.5%及42.8，P0.05。结论 在HFRS病程中，病毒血症持续时间与病情轻重密切相关。

目的 克隆与结核分支杆菌耐异烟肼密切相关的KatG基因，实现其在大肠杆菌中的表达对其酶活性进得初步检测。方法 构建含KatG基因的表达质粒PET24b-KatG, 转化大肠杆BL21（DE3）菌株，获得稳定的高表达菌株后对表达产物进行过氧化氢酶活性的初步检测。结果 限制性内切酶分析结果显示所构建的pET24b-KatG表达质粒已成功克隆KatG基因。含pET24b-KatG表达质粒的大肠杆菌在导丙基硫代β-D-半乳糖苷（IPTG）诱导下表达，对表达产物进行SDS-PAGE，发现KatG表达产物相对分子质量约为80×103，表达产物约占总蛋白量的17.7%。具备过氧化氢酶活性。可期满此方法研究结核分支杆菌的耐药机制。

目的 探讨过氧化氢酶编码基因（KatG）基因点突变和结核分枝杆菌异烟肼（INH）耐药性之间的关系，筛选相关位点用于筛查临床INH耐药株基基型。方法 采用三步法聚合酶链反应（PCR）对临床耐异烟肼菌株中发现的6个位点进行定点诱变，用含诱变基因的pET24b质粒转化大肠埃希菌BL21菌株，在异丙基硫代-D半乳糖苷（IPTG）导下表达，使用镍亲和柱和Q-琼脂糖快速流动凝胶纯化各KatG诱变蛋白并测定其过氧化氢酶和过氧化物酶活性。结果 完成KatG基因6个位点的诱变及相应诱变蛋白的表达和纯化，过氧化氢酶、过氧化物酶活性测定发现，3个诱变蛋白[KatG（W321G）、KatG（R418Q）和KatG（A456S）]基本失活，其余3个诱变蛋白的活性亦有不同程度下降。结论 所引入的6个突变均可造成KatG蛋白过氧化氢-过氧化物酶活性下降，与结核分枝杆菌1NH耐药有关，可用于筛查临床INH耐药株基因型。

目的 对分支杆菌的一种分泌蛋白Ag85B的基因进行克隆、表达，为结核病进行诊断打下基础。方法以结核杆菌H37Rv株基因组DNA为模板以PNA为模板，以PCR法对基因ag85b进行扩增，产物与载体质粒pET24b构建表菌JM109（DE3）菌株内，对转化菌株以IPTG进行诱导后，破菌，离心，上清进行SDS-PAGE电泳。结果 电泳发现转化了重组质粒的菌株有蛋白表达，所达的蛋白分相对分子质时为30000。结论 目的基因克隆入宿主菌内，重组结核杆菌分泌蛋白Ag85B的成功表达为进行临床诊断试验奠定了基础。

目的 表达与纯化结核分支杆菌katG蛋白，为深入研究异烟肼耐药机制奠定基础。方法将含有KatG基因的PEt24b-katG表达载体转化大肠杆菌BL21 (DE3) 菌株，在异丙基硫代-β-D半乳糖苷（IPTG）诱导下表达，分别对不同诱导时司的表达产物进行SDS-PAGE以及考马斯亮蓝染色。获得稳定的高表达菌株后采用Xpress TM蛋白纯化系统对超声破菌液进行纯化。最后对纯化产物进行过氧化氢酶活性的初步检测。结果 对诱导后的重组大肠杆菌菌液进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）以及考马斯亮蓝染色后发现相对分子质量约为80000。表达蛋白量约占总蛋白量的17.7%。对重组KatG基因表达产物进行纯化的结果发现，以350mmol/L咪唑洗联时的纯化效果最理想，蛋白纯度可达99%以上。对表达产物进行过氧化氢酶活性初步检测证明，重组的katG基因产物具有过氧化氢酶活性。结论通过PET24b-katG表达质粒转化大肠杆菌可获得基因重组的katG高表达菌株，表达产物具有一定酶活性，经纯化后可达到较高的纯度。