TaqMan-MGB荧光定量PCR检测人载脂蛋白A5基因方法的建立及评价

目的建立以TaqMan-MGB荧光探针为特点的荧光定量聚合酶链反应(PCR),用于检测人载脂蛋白A5(apo A5)基因。方法针对人apo A5基因设计特异性引物和TaqMan-MGB荧光探针,以重组克隆质粒pPCR-Script-apo A5为DNA模板,在荧光定量PCR仪上建立TaqMan-MGB荧光定量PCR检测方法和标准曲线,进行灵敏度、重复性、特异性实验。结果建立的定量标准曲线阈值循环数(Ct)与模板拷贝数呈良好线性关系(r=0.998);最低检测浓度为103拷贝/μL;扩增效率(E)为110.2%,且重复性好。结论成功建立检测人apo A5基因的TaqMan-MGB荧光定量PCR。该法具有较好的灵敏度、特异性及重复性。     

EvaGreen实时荧光定量PCR检测猪细小病毒方法的建立

目的 建立以EvaGreen为染料的实时荧光定量PCR检测猪细小病毒(PPV)的方法,为血液制品中病毒去除效果的工艺验证提供高效准确的技术平台.方法 根据PPV的VP2基因保守序列,设计并合成引物.对目的片段进行PCR扩增,将扩增的PPV病毒VP2基因片段克隆入PMD19-T载体,重组质粒PMD19-T-VP2经测序鉴定正确后,作为标准品模板,用于标准曲线的绘制和该实时荧光定量PCR方法的灵敏度、特异性和重复性检测的材料.结果 应用重组质粒PMD19-T-VP2制作的荧光定量PCR扩增曲线循环阈值与模板浓度具有良好的线性关系;该方法检测灵敏度的下限能达到102copies/μl;与其他DNA病毒和同种属的细小病毒无明显的交叉反应;连续重复检测高、中、低浓度样品,批内批间变异系数小,重复性好.结论 以EvaGreen为染料的实时荧光定量PCR检测PPV的方法提高了检测灵敏度,缩短了工艺验证的时间.     

免提取冻干式百日咳鲍特菌核酸检测方法建立及应用

目的本研究建立快速、便携、特异、敏感的百日咳鲍特菌实时定量PCR(Q-PCR)核酸检侧方法,并初步探索在呼吸道感染患者中百日咳鲍特菌(Bordetella pertussis)检测的应用价值。方法靶基因采用IS481基因,优化反应试剂实现免核酸提取直接扩增,对体系进行冻干处理,简化操作步骤。并对所收集得到的上呼吸道感染者的咽拭子标本进行检测评价。结果本检测体系检出限达到100copies/mL,227例急性上呼吸道感染者的咽拭子标本中,其阳性检出率为3.96%。结论成功建立了高敏感、简便、快速的百日咳核酸检测方法,为百日咳诊断提供了新手段。     

双重PCR快速检测百日咳杆菌

目的:以百日咳毒素S1亚基启动子ptxA-Pr基因和插入序列IS481为目的基因,建立敏感、特异的双重PCR快速检测百日咳杆菌方法.方法:运用百日咳杆菌ptxA-Pr和IS481基因序列特异性引物,采用双重PCR技术同时扩增百日咳杆茵的特异性基因ptxA-Pr和IS481.通过构建目的质粒获得阳性对照,测序并与GenBank比对序列验证扩增产物.百日咳标准茵株DNA 10倍系列稀释为模板.采用此方法扩增双基因,检测此方法敏感性.扩增肺炎克雷伯茵、肺炎链球茵、铜绿假单胞茵、金黄色葡萄球菌、大肠杆菌及阳性样本DNA,检测此方法特异性.结果:百日咳杆菌标准株和阳性样本均能同时扩增ptxA-Pr和IS481目标序列,分别为191、145 bp.构建质粒后测序结果与GenBank对比一致.每个反应体系能检测到的标准菌株核酸最小量为1.65×10<'-2>ng.其他菌株检测未出现非特异性扩增.结论:双重PCR扩增百日咳杆菌ptxA-Pr和IS481基因的方法可用采特异快速的检测百日咳杆菌.     

百日咳杆菌荧光定量PCR检测方法的建立和应用

目的 建立快速、准确、特异的定量检测百日咳杆菌的方法,并进行临床应用研究.方法 根据百日咳杆菌IS481基因序列,设计并合成引物和荧光探针,建立百日咳杆菌荧光定量PCR检测方法,并对方法的特异度、重复性和灵敏度进行评价,检测百日咳疑似患者咽拭子225份和健康者咽拭子30份.结果 该方法的标准曲线显示模板浓度在102～108拷贝/μl线性范围与其循环阈值(Ct)具有较好的线性关系,相关系数(r)为0.998,最小检出量为102拷贝.特异度较好,灵敏度较高,重复性实验结果显示在同一时间检测高低浓度阳性克隆质粒(2×107与3×103拷贝/μ1)10次,连续检测5次,变异系数(CV)为5.78%～16.7%.在不同时间检测高低浓度阳性克隆质粒(2×107与3×103拷贝/μl),连续7次,CV为8.25%～14.9%.经检测,疑似患者的咽拭子有41份样本为阳性,30份健康人咽拭子均为阴性.结论 由于本实验建立的荧光定量PCR方法快速、灵敏度高、特异度好,适合临床实验室进行临床标本的百日咳杆菌的定量检测,有较大的应用前景.     

嗜肺巴斯德菌TaqMan MGB探针实时荧光定量PCR快速检测方法的建立及应用研究

目的 建立嗜肺巴斯德菌的TaqMan MGB探针实时荧光定量PCR快速检测方法.方法 针对嗜肺巴斯德菌16SrRNA基因设计特异性引物和探针,建立嗜肺巴斯德菌TaqMan MGB探针实时荧光定量PCR检测方法,并验证该方法的特异度、敏感度和稳定性.对2008～2011年采集的1 680份样本进行检测.结果 嗜肺巴斯德菌TaqMan MGB探针实时荧光定量PCR检测方法具有高度特异性,对多杀巴斯德菌、产气巴斯德菌、支气管鲍特杆菌、肺炎克雷伯杆菌、大肠埃希菌、铜绿假单胞菌均无交叉反应,检测灵敏度达22拷贝.标准曲线显示备浓度范围内具有良好的线性关系,相关系数为0.999,斜率为-3.488,PCR效率为100％.荧光定量PCR检测1 680份样本,检出137份嗜肺巴斯德菌阳性.该方法可直接从样本中特异性地检出嗜肺巴斯德菌.结论 TaqMan MGB探针实时荧光定量PCR方法具有灵敏、特异、稳定的特性,适用于嗜肺巴斯德菌的快速检测.     

鼠疫多重荧光定量PCR内标检测方法的建立与应用评价

  目的  建立一种鼠疫多重荧光定量PCR内标检测方法,并进行应用效果评价。  方法  选择鼠疫菌染色体YPO0393基因与pMT1质粒caf1基因为靶基因,设计合成YPO0393-内标模板、特异性引物和TaqMan荧光探针,构建鼠疫多重荧光定量PCR内标检测体系;对非鼠疫菌DNA、不同稀释浓度鼠疫菌DNA、野外监测样本进行检测,评价该方法的特异性、灵敏性、重复性和应用效果。  结果  采用多重荧光定量PCR内标方法,8株鼠疫菌DNA均出现明显的扩增曲线,12株非鼠疫菌DNA未显示扩增曲线,提示该方法特异性良好。 不同浓度的鼠疫EV76疫苗株DNA,检测最低限为22.5×10?4 ng/μL,变异系数为0.99～3.42,提示灵敏性、重复性较好。 105份野外监测样本中,荧光定量PCR内标方法检测阳性的6份,与普通PCR方法检测结果一致,4份样本分离培养出鼠疫菌且采用PCR方法检测阳性。  结论  通过设置双靶基因与内标对照,本研究建立的鼠疫多重荧光定量PCR内标方法可降低检测假阳性率,特异性、灵敏性和重复性理想,可用于鼠疫快速检测。     

DD3基因实时荧光定量RT—PCR检测前列腺癌特异性方法的建立

目的 建立DD3基因实时荧光定量PCR检测前列腺癌特异性方法,为前列腺癌的快速诊断提供分子诊断依据.方法 根据Genebank中的 DD3 mRNA全序列,设计DD3基因的特异引物和探针,采用基因重组技术构建用于DD3基因检测的定量标准品;建立DD3基因的实时荧光定量方法.结果 成功构建了用于DD3基因荧光定量PCR检测的标准重组质粒和DD3基因实时荧光定量PCR方法;经稳定性、特异度、重复性和敏感度实验方法学评价,DD3基因实时荧光定量PCR方法的最低检测限为1.64 copy/ml,线性范围为1.64～1.64×1012copy/ml.结论 DD3基因实时荧光定量PCR检测前列腺癌特异性方法的建立,将为前列腺癌特异性诊断及其临床应用奠定方法学基础.     

人类Gfi1基因SYBR Green I实时荧光定量PCR检测方法的建立

目的 建立测定人类Gfi1mRNA表达量的SYBR Green I实时荧光定量PCR方法,为进一步研究新基因的功能奠定基础.方法 以Gfi1基因为靶基因设计引物.构建携带GficDNA的质粒plox-Gfi1,经过纯化,质粒浓度测定,拷贝数的计算及10倍的梯度稀释制备标准品.应用ABI stepone PCR仪对Cfi1mRNA进行实时荧光定量PCR检测,建立标准曲线和熔解曲线.结果 建立了Cfi1mRNA表达的实时荧光定量PCR方法,本法线性范围为6.36×102～6.36×108copies/μl,线性相关系数y2为0.996,熔解曲线为单峰,Tm值为(89.98±0.22)℃,标准品的循环阈值批内变异系数和批间变异系数分别为1.35%～3.61%和1.49%～3.42%.结论 本研究建立的Gfi1mRNA表达实时荧光定量PCR检测方法速度快,灵敏度高,特异性强,重复性及稳定性好,可用于Gfi1基因的定量检测.     

实时荧光定量PCR法检测产气荚膜梭菌

目的:运用实时荧光定量PCR法检测产气荚膜梭菌,为早期快速诊断气性坏疽提供新方法.方法:以产气荚膜梭菌16s rDNA基因序列为模板,在其保守区域设计特异性引物与探针,将PCR扩增所得产物片段克隆,作为定量检测的标准品,绘制标准曲线.并对荧光定量PCR体系与反应条件进行优化,验证方法的特异性、敏感性、重复性及可行性.结果:实时荧光定量PCR法对产气荚膜梭菌的检测具有高度特异性,与创伤弧菌等24种相关细菌等均无交叉反应;检测灵敏度以纯菌计数达9×102cfu/mL,相当于9 cfu/反应;反应体系有较高稳定性;整个操作过程仅需3 h;300例创伤可疑分泌物样本的荧光定量PCR检测结果与细菌培养结果一致.结论:实时荧光定量PCR法特异、灵敏、快速,适用于产气荚膜梭菌的临床检测及突发事件的批量检测.     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.