重组免疫印迹试验对3种进口抗-HCV ELISA试剂组合应用的探讨

目的探讨3种进口抗-HCV ELISA试剂两两组合的应用价值。方法采用3种进口抗-HCV ELISA试剂同时筛查51例抗-HCV结果不一致的弱阳性标本,并用抗-HCV分段确证试剂进行确证。结果 51例抗-HCVELISA弱阳性标本,抗-HCV分段确证试剂阳性35例,可疑16例,16例可疑标本经NAT检测分析:HCV RNA阳性7例,确认为阳性;9例为阴性,判定为抗-HCV可疑。单一ELISA试剂假阴性率19.24%~72.41%,试剂组合后假阴性率4.76%~30.95%。结论选择抗-HCV检测试剂的最佳组合对保证输血安全意义重大。     

抗-HCV酶联免疫吸附试验灰区临界值设置的探讨

目的评价与验证本实验室抗-HCV试验设置0.7CO(临界值)的合理性。方法本研究内容包括4个方面:1)参照CLSI发布的EP12-A2指南,通过实验确定抗HCV试验C5-C95区间。2)对抗-HCV灰区标本进行抗体确认实验。3)绘制ROC曲线确定抗-HCV试验最佳CO值。4)通过实验室既往数据,分析HCV RNA单阳性标本ELISA结果分布(S/CO值)与灰区临界值的关系。结果 1)C50±20%浓度检测结果阴性数和阳性数≥95%,C50-20%-C50+20%浓度范围包含了C5-C95区间,灰区临界值范围应在S/CO值为0.88-1.39区间内。2)对58例抗-HCV灰区标本(S/CO值0.70-0.99)进行RIBA确认试验,其中51例确认结果为阴性,7例确认结果为可疑(IND);并对57例阴性标本(抗-HCV、NAT联检均为非反应性)进行RIBA试验,其中53例确认结果为阴性、4例确认结果为可疑。经卡方检验2组可疑结果检出情况无统计学意义(χ2=0.365,P0.05)。3)绘制抗-HCV的ROC曲线,AUC为0.977、最适CO值为0.857(现用CO值为0.62-0.66)。4)2010年11月2日-2013年12月31日检测标本886 291份,抗-HCV阳性中包括697份灰区标本、NAT检测结果均为阴性;共检出HCV RNA单阳性标本9例,其抗-HCV检测结果(S/CO值)分布区间为0.02-0.07,与阴性标本分布区间重叠、距0.7CO界限甚远。结论本实验室现阶段抗HCV试验设置0.7CO灰区临界值过于严苛、实验结果支持取消灰区设置。此外,本文所提供的4种评价方法为其他实验室在设置ELISA试验灰区临界值提供了一种思路。     

抗-HCV,HCV RNA检测在丙型肝炎中的应用价值探讨

目的探讨抗-HCV,HCV RNA检测在丙型肝炎诊断中的临床价值。方法选择2018年5月-2018年12月检验科收集的143例抗-HCV(S/CO≥1)初筛实验阳性的血清标本,分别采用酶联免疫吸附法(ELISA)及荧光定量聚合酶链反应法(PCR)、日立7600全自动生化分析仪,进行抗-HCV、HCV RNA病毒载量、ALT检测。结果143例抗-HCV初筛阳性患者中,99例HCV RNA阳性(69.23%),且随着S/CO比值的增高HCV RNA检出的阳性率增加,差异有统计学意义(P<0.01);99例HCV RNA阳性患者中93例抗-HCV的S/CO>10,但随着S/CO的增大,HCV RNA病毒载量高低水平出现的阳性率没有增加(P>0.05);HCV RNA阳性患者ALT异常率(46.46%)高于阴性患者(20.45%),差异有统计学意义(P<0.05);44例HCV RNA阴性(30.76%)患者中有33例的S/CO>10,且有9例ALT异常。结论ELISA法检测血清抗-HCV诊断丙型肝炎与荧光定量PCR检测法均存在假阳性或假阴性情况;荧光定量PCR法的阳性率低于ELISA法;在临床诊断中ELISA法抗-HCV初筛阳性的样本应同时进行HCV RNA及ALT的联合检测,以避免漏诊、误诊,也为临床抗病毒的有效评估提供可靠的实验室依据。     

抗-HCV阳性样本的分片段抗体辅助实验研究

目的调查并证实ELISA法检测HCV抗体的假阳性问题。方法采用抗-HCV分片段检测试剂对2次或2次以上ELISA法检测HCV抗体阳性的样本进行辅助确认实验。结果ELISA法检测379份HCV抗体阳性的样本,分片段确认阳性样本61份,可疑阳性样本57份,总计118份,确认阳性样本百分率31.13%(118/379)。结论采用国产的分片段检测试剂对抗-HCV ELISA法检测的阳性样本进一步确认,同时再辅以PCR检测,对减少血液资源的浪费具有现实意义。     

抗-HCV CLIA检测S/CO值与确证试验结果的相关性探讨

目的：探讨抗丙型肝炎病毒（HCV）抗体化学发光标记免疫分析法（CLIA）检测S/CO值与确证试验阳性的相关性。方法采集用CLIA检测抗-HCV 样本测定值/临界值（S/CO）在0.9～12之间的标本124例,S/CO值〉12.0的标本25例。以重组免疫印迹法（RIBA）最终确认。结果抗-HCV S/CO值在0.9～1.0之间的共20例,RIBA法确证阳性的0例,阴性的15例（占75%）,不确定的5（占15%）例;1.1～5.0之间的共92例,RIBA法确证阳性的5例（5.4%）,阴性的65例（占70.7%）,不确定的22（占23.9%）例;5.1～12.0之间的共12例,RIBA法确证阳性的3例（25%）,阴性的5例（占41.7%）,不确定的4（占33.3%）例。S/CO值〉12.0时,25例标本中RIBA法确证阳性的20例（80%）,阴性的2例（占8%）,不确定的3（占12%）例。 CLIA法检测HCV抗体的敏感性和特异性分别为100%和16.53%。结论抗HCV用CLIA法检测 S/CO值时,RIBA确证的阳性率随着S/CO值的增加显著升高（P〈0.05）。对CLIA法结果S/CO偏低的样本应慎重,综合分析,合理解释,不确定病例随访,必要时用RIBA法进一步验证,避免假阳性。     

利用RIBA实验确定VITROS抗-HCV检测试剂CUT-OFF值的分析

目的采用重组蛋白免疫印迹分析(RIBA)实验设置该实验室常用的VITROS全自动免疫分析仪进行丙型肝炎病毒抗体(抗-HCV)检测试剂的CUT-OFF值。方法收集抗-HCV阳性标本217例,其中吸光度比临界值(S/CO)8.0有101例,占46.5%,S/CO3.0的极低阳性共69例,占31.8%,拟用RIBA对S/CO8.0的样本进行确认,从而确定抗-HCV的S/CO值与RIBA结果之间的相关关系,以此来建立该实验室CUT-OFF值。对61例S/CO8.0(包括S/CO3.0共49例,3.0～8.0共12例)进行了RIBA确认实验。结果根据RIBA结果可分为3组,31例阴性、21例阳性和9例不确定。其S/CO值分别为阴性组1.67±0.41,阳性组4.41±2.72,不确定组2.64±0.38,不确定组和阳性组的S/CO值比较,差异有统计学意义(P0.05)。抗-HCV的S/CO值与RIBA结果之间呈正相关。根据受试者工作特征曲线(ROC曲线)分析抗-HCV的CUT-OFF值为2.10,ROC曲线下面积(AUC)可达0.94,特异度为92.4%,灵敏度为85.2%。结论VITROS抗-HCV的S/CO值与RIBA结果间呈正相关,S/CO值越高,RIBA确认阳性的比例越高;当CUTOFF值为2.10时,可以排除大多数的假阳性结果,是一个合适的临界值。     

艾滋病病毒感染对酶联免疫吸附试验试剂检测静脉吸毒人员丙型肝炎病毒抗体反应强度影响的探讨

目的探讨艾滋病病毒(HIV)感染对ELISA试剂检测静脉吸毒人员丙型肝炎病毒(HCV)抗体的影响,为HIV、HCV混合感染检测策略的提出和修改提供理论依据。方法按是否感染HIV分组对两种抗-HCVELISA试剂检测反应强度(S/CO)≥1的分布进行对比,采用SPSS 15.0软件分析。结果两组样本经两种试剂检测反应强度(S/CO)的构成差异有统计学意义(P0.05),HIV阳性组HCV抗体检测低反应强度的构成高于HIV阴性组(P0.05)。对科华试剂检测为低反应强度的标本,与用Ortho试剂检测结果的一致性在两组间差异有统计学意义(P0.05)。结论是否感染HIV对科华HCV抗体ELISA试剂及Ortho HCV 3.0 ELISA试剂反应强度均有影响。HIV感染者可能出现HCV抗体ELISA检测不确定或假阴性反应,弱阳性反应标本可增加假阳性可能。     

江苏地区无偿献血者HCV基因型的分布

目的探讨江苏地区献血者感染的HCV基因型及亚型。方法收集2013年来自江苏省血液中心ELISA双试剂检测抗-HCV阳性献血者血清标本,使用HCV核酸定量检测试剂盒检测HCV RNA载量;同时使用RNA提取试剂提取HCV RNA,反转录PCR法扩增HCV Core区基因片段,并对扩增产物进行测序,利用进化树分析基因型和亚型。结果 2013年抗-HCV阳性标本139例(0.20%),其中64例抗-HCV阳性血清标本经荧光定量检测,RNA阴性30份,阳性34份。经巢式PCR扩增能够分型的标本24份,包括1a(71.7%)、1b(7.5%)、2a(7.5%)和3b(1.9%)3种基因型和4种亚型。年龄偏大(35岁)以及男性的HCV RNA阳性标本的病毒滴度与抗-HCV水平(S/CO值)都高于RNA阴性标本,并且存在性别差异,但年龄间无差异。结论江苏无偿献血者感染的HCV基因型以1型为主,其中1b为优势基因亚型。病毒血症献血者的HCV抗体水平显著升高,HCV RNA在自然感染进程中的变化有待通过进一步随访进行研究。     

丙型肝炎病毒抗体酶联免疫吸附试验阳性判断值在献血员血液筛检中的意义

目的探讨丙型肝炎病毒(HCV)抗体酶联免疫吸附试验(ELISA)测定阳性判断值(Cut-off)“灰区”在献血员血液筛检中的应用价值。方法采用逆转录-聚合酶链反应(RT-PCR)方法检测了503份抗-HCV ELISA测定为阴性的献血员血清(浆)标本的HCV RNA。如HCV RNA检测为阳性，则使用重组免疫印迹(RIBA)方法进一步检测抗HCV。结果在503份抗-HCV ELISA阴性献血员血清(浆)标本中，发现有5份HCV RNA阳性，其中2份标本抗HCV ELISA测定S/CO比值小于0．5，RIBA结果均为阴性。另外3份抗HCV阴性(ELISA检测的S/CO值在0．8-0．9之间)但HCV RNA为阳性的献血员血标本，进一步进行RIBA检测，发现其中2份为抗核心区(C22)单独阳性，另外1份为抗NS3单独阳性。阳性标本HCV RNA的含量测定均约为10^4拷贝/ml。结论为尽可能减少输血后HCV感染的发生，有必要将抗-HCV ELISA测定的Cut-off值下移20％，因为S/CO比值接近Cut-off值的血液有很大可能为HCV感染者。     

临汾地区丙型肝炎病毒感染检测结果分析

目的了解本地区普通人群中丙型肝炎病毒(HCV)感染实验室检测情况。方法收集2015年1月1日至12月31日来山西省临汾市人民医院就诊的申请检测丙型肝炎病毒抗体(抗-HCV)的门诊及住院患者标本共21 120例,采用酶联免疫吸附试验(ELISA)进行抗-HCV的筛查,对ELISA筛查阳性的标本采用实时荧光定量聚合酶链式反应(PCR)法进行丙型肝炎病毒核酸(HCV RNA)检测。结果 21 120例标本中抗-HCV筛查阳性率为0.69%(146/21 120);在146例抗-HCV标本中其中47例检测出HCV RNA,检出率为32.2%(47/146);检测出HCV RNA标本的抗-HCV的浓度试剂测量值/阳性判定值之比值(S/CO值)介于8.32~25.80(8.0)。结论在山西临汾地区就诊的普通人群中抗-HCV阳性分布比例以及HCV RNA检出率均较低,可检出HCV RNA的患者抗-HCV浓度相对较高。     

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.     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.     

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.