聚合酶链反应对小儿肺炎多病原检测及临床意义

目的 了解我区病毒性肺炎的病原以及病原之间的关系、病原与临床的关系。方法 对 2 0 0例肺炎患儿鼻咽部分泌物用PCR法检测呼吸道合胞病毒、腺病毒 ,流感Ⅰ、Ⅱ型 ,肺炎支原体。结果 呼吸道合胞病毒 4 8.2 %、腺病毒 2 3.4 %、流感Ⅰ型 2 3.4 %、流感Ⅱ型 2 .1%、支原体 2 .8% ,总阳性率 70 .5 % ,6个月以内以呼吸道病毒及流感Ⅰ型为主 ,6个月～ 3岁以腺病毒及呼吸道合胞病毒为主 ,年长儿则支原体感染率增加。结论 采用PCR法进行的病毒检测提高阳性率。我区小儿肺炎常见病原以呼吸道合胞病毒为主 ,腺病毒及流感病毒次之 。

胃癌患者术中门静脉血p53和K-ras基因的检测及意义

目的 研究胃癌患者术中门静脉血p53和K-ras基因突变率变化,探讨手术对癌细胞播散的影响.方法 应用聚合酶链反应-单链构象多态性分析技术,检测98例胃癌患者术中胃癌探查前后门静脉血p53和K-ras基因的突变阳性率.结果 胃癌探查前后临床Ⅲ期胃癌患者p53基因突变阳性率分别为36.6%、58.5%,K-ras基因突变阳性率分别为29.3%、51.2%;Ⅳ期胃癌患者p53基因突变阳性率分别为46.7%、73.3%,K-ras基因突变阳性率为53.3%、80.0%;Ⅲ、Ⅳ期胃癌患者探查前后p53基因和K-ras基因突变阳性率的差异有统计学意义(均P<0.05),而Ⅰ、Ⅱ期胃癌患者探查前后上述两种基因突变阳性率的差异无统计学意义(P>0.05).两种基因突变阳性者24个月内肝转移发生率均明显高于阴性者(均P<0.05).结论 手术操作刺激增加了中晚期胃癌患者门静脉血中游离癌细胞的数量,后者可能是胃癌肝转移的危险因素.

济南市流动采血点A型与B型血小板捐献者HPA-2基因型频率的比较

目的 探讨血小板糖蛋白HPA-2基因型在A型和B型血小板捐献者中的分布频率.方法 收集血小板捐献者A型44名,B型44名,应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)扩增GP HPA-2基因,产物经限制性内切酶Hinl Ⅰ消化后确定其基因型.结果 在A型和B型血小板捐献者中,血小板糖蛋白HPA-2 2a/2a基因型频率分别是0.95、0.91;2a/2b基因型频率分别是0.05、0.07;2b/2b基因型频率分别是0、0.02.结论 血小板糖蛋白HPA-2基因型频率在A型和B型血小板捐献者中的分布无显著性差异.

尿道分泌物(NG、CT、UU、MH)四种病原体感染状况的研究

目的 快速准确检测尿道分泌物病原体感染 ,包括淋病奈瑟氏菌 (NG) ,沙眼衣原体 (CT) ,解脲支原体 (UU )及人型支原体 (MH)引起的感染。方法 应用PCR技术检测 2 4 9份女性分泌物和男性分泌物。结果 NG、CT、MH、UU阳性率分别为 1 3% (39/2 4 9)、9.7% (2 9/2 4 9)、6 .7% (2 0 /2 4 9)、1 0 .4 % (31 /2 4 9)。结论 性病和非性病泌尿生殖道感染的病人中不仅存在淋病奈瑟氏菌 ,也存在CT、UU。

Clinical Application of Multiplex PCR Assay for the Diagnosis of the Etiology of Genital Ulcer Disease Among Patients Attending STD Clinics in Guangzhou, China

Objectives: To develop a method of simultaneous PCR detection of Haemophilus ducreyi, Treponema pallidum, andHerpes Simplex Virus Types 1 and 2 from genital ulcersamong patients attending STD clinics in Guangzhou, China;and evaluate the clinical application of multiplex PCR (M-PCR) assay for diagnosing the etiology of genital ulcerdiseases (GUD). Methods: 244 patients with a genital ulcer were evaluated.Clinical etiology of GUD was based on physical appearanceand microbiologic evaluations that included darkfieldmicroscopy examination (D-F) and serology test for syphilis(STS). Swabs of each genital ulcer were tested for HSVantigen by enzyme immunoassay (EIA) and processed in anM-PCR assay for simultaneous detection of T pallidum, HSVand H ducreyi. Results: The standard strains of T pallidum, HSV and Hducreyi were amplified by M-PCR, producing amplifiedproducts of 260bp,432bp,170bp, respectively. The sensitivityof M-PCR is 10~2 pg DNA. M-PCR assay for T.pallidum, HSVand H ducreyi showed good agreement en compared with D-F detection for T pallidum, STS, H ducreyi culture and EIAfor HSV antigen (Kappa scores are 0.774,0.704,0.793,0.756,respectively). Conclusions: The M-PCR is a convenient, accurate andreliable assay for the detection of T pallidum, HSV and Hducreyi from genital ulcers, and can be used as a method ofdiagnosing the etiology of GUD.

DNA双链断裂修复基因XRCC4多态性与肺癌易感性的关系

目的:探讨DNA双链断裂修复基因X-射线修复交叉互补4(X-ray repair cross-complementing 4, XRCC4)基因单核甘酸多态性(single nucleotide polymorphism, SNP)与肺癌发生风险的关系.方法:采用病例-对照研究的方法,应用聚合酶链反应-限制性片段长度多态性(polymerase chain reaction-restriction fragment length polymorphism, PCR-RFLP)技术和TaqMan探针基因分型技术对781例肺癌患者和781健康志愿者(作为对照)进行XRCC4 rs6869366、rs3734091和rs1056503多态性的检测;结合PCR和定点突变技术,分别构建含有XRCC4基因启动子rs6869366位点不同等位基因的重组质粒,以双荧光素酶报告系统检测SNP位点碱基突变对启动子活性的影响.结果:XRCC4 rs6869366位点携带G等位基因的基因型(T/G+G/G)可显著增加肺癌的患病风险[比值比(odds ratio, OR)=1.607, 95%可信区间(confidence interval,CI): 1.138~2.270];rs6869366与rs3734091存在连锁不平衡,携带由其构建的单体型GC或单体型对TC/GC者患肺癌的风险增加(OR=1.993,95%CI:1.194~3.329;OR=2.013,95%CI:1.174~3.452);含rs6869366不同等位基因的启动子转录活性差异无统计学意义.结论:XRCC4 rs6869366位点多态性与肺癌的易感性有关,其影响机制还需进一步研究.

Effects of Silver Nanoparticles on Soil Ammonia-Oxidizing Microorganisms Under Temperatures of 25 and 5℃

The excellent bactericidal performance of silver nanoparticles （Ag NPs） has led to their wide applications, resulting in increasing concerns about their potential environmental impacts. This study evaluated the influences of different concentrations of Ag NPs （0, 1, 10, and 100 μg g^-1 dry soil） on the ammonia-oxidizing microorganisms in soil at cultivation temperatures of 25 and 5 ℃ for 37 d. The results showed that 1μg g^-1 dry soil of Ag NPs had no acute effects on the ammonia-oxidizing microorganisms. However, 10 and 100μg g^-1 dry soil of Ag NPs levels were found to significantly inhibit the activities of soil nitrification, with a decrease of 69.89% and 94.55%, respectively, at 25 ℃ and 61.65% and 83.79%, respectively, at 5℃ compared to the control （0 μg g^-1 dry soil of Ag NPs）. These levels of Ag NPs also obviously decreased soil urease activity from about 380.47 ± 0.07 （at 5℃） and 529.76 ± 13.44 （at 25℃） mg N g^-1 dry soil d^-1 to 61.70 ± 2.97 and 68.29 ± 8.22 mg N g^-1 dry soil d^-1, respectively, after 37 d of cultivation. Quantitative polymerase chain reaction showed the abundance of ammonia-oxidizing archaea and bacteria. For the same exposure time, the effects of Ag NPs on the activities of ammonia-oxidizing microorganisms and urease decreased with decreasing temperature. The threshold concentration of Ag NPs that induced negative effects on ammonia-oxidizing microorganisms was higher at 5 -C than at 25 -C. Therefore, the temperature has a major impact on the toxicity of Ag NPs to ammonia-oxidizing microorganisms and on the urease activity, with toxicity being reduced with decreasing temperature.