SYBR Green Ⅰ实时荧光定量方法检测结直肠癌患者外周血CEA-mRNA表达研究

目的 建立检测CEA mRNA表达水平的实时荧光定量逆转录聚合酶链反应(FQ-PCR)方法,探讨外周血CEA mRNA表达在结直肠癌患者中的应用价值.方法 应用SYBR GreenⅠ作为荧光染料,以GAPDH作为内对照,建立检测CEA mRNA的FQ-PCR方法,并对56例结直肠癌患者外周血中CEA mRNA的表达水平进行了检测.结果 56例结直肠癌患者中有33例外周血CEA mRNA表达为阳性,表达水平为1.07±2.99,阳性表达率为66.1%(37/56),30例结直肠良性疾病患者中有2例外周血CEA mRNA表达为阳性,表达水平为0.13±0.07,阳性表达率为6.7%(2/30),30例健康成人外周血CEA mRNA表达均为阴性;结直肠癌患者外周血CEA mRNA在不同病理分化程度中表达水平无明显变化(P＞0.05),但在Dukes C+D期表达水平(1.73±2.15)及表达阳性率82.8%(24/29)均显著高于Dukes A+B期表达水平(0.39±0.87)及表达阳性率48.1%(13/27)(P＜0.01).结论 该FQ-PCR方法简便、特异、可靠;检测外周血CEA mRNA表达水平,对诊断结直肠肿瘤病变比血清CEA蛋白具有更高的敏感性,可提高早期结直肠癌诊断符合率;在发生转移的Dukes C+D期其表达水平及表达阳性率均显著高于未发生转移的Dukes A+B期,可作为鉴别结直肠癌患者发生微转移的有力证据之一,动态观察其水平变化对判断结直肠癌患者的预后有重要价值.     

结直肠癌患者外周血生存素检测的临床意义

目的采用实时定量逆转录-聚合酶链反应（RT—PGR）技术，检测结直肠癌患者外周血中生存素基因的表达，并分析其与转移之间的关系，探讨其成为无创性结直肠癌诊断、转移检测指标的可能性。方法取58例结直肠癌患者，46例非癌性肠道病变患者和29名健康成人的外周血，用实时定量RT-PCR的方法检测Survivin基因的表达，分析其与临床病理因素之间的关系。结果正常对照组外周血中未检测到Survivin mRNA表达转录本。癌前病变患者生存素表达检测率为6．25％，平均拷贝数为1．77±0．75；肠癌组患者生存素表达检测率为79．3％，平均拷贝数为5．62±1．32，两者差异有统计学意义（P〈0．01）。Survivin的表达在各性别、年龄、及不同分化组之间差异无统计学意义，而有、无淋巴结转移组之间以及Dukes分期C、D组与A、B组之间则发现Survivin的表达显著增高（P〈0．05）。生存分析表明，Survivin mRNA的高表达者4年生存率（62．9％）显著低于低表达者（86．6％）（P〈0．05）。回归分析发现，Dukes分期为影响肠癌预后有的独立因素。结论生存素基因在结肠癌患者中存在过表达，并可能与转移有关，采用实时定量RT—PGR检测外周血中生存素基因的表达，可能成为一种较理想的无创性结肠癌诊断、转移检测方法。     

骨髓增生异常综合征患者外周血树突细胞数量、亚群及其表面协同刺激分子表达的研究

目的 检测骨髓增生异常综合征（MDS）患者外周血树突细胞（DC）总量、亚群（pDC和mDC）比例及其表面协同刺激分子（CD80、CD86和CIMO）表达，探讨MDS患者细胞免疫异常的形成机制。方法 选取38例MDS患者及19名正常对照，采用荧光素单克隆抗体标记法和流式细胞术检测MDS患者外周血中Lin1^—HLA-DR^＋细胞（DC）、Lin1^-HLA—DR^＋CD123^＋细胞（pDC）、Lin1—HLA—DR^＋CD11c^＋细胞（mDC）的数量以及CD80、CD86和CIMO在DC膜上的表达。结果低危MDS组、高危MDS组和正常对照组外周血DC总量分别为（33．7±7．0）×10^6／L、（56．3±29．0）×10^6／L和（12．1±1．4）×10^6／L（P〈0．05），pDC数量分另U为（12．6±4．1）×10^6／L、（3．6±1．0）×10^6／L和（6．6±0．7）×10^6／L（P〉0．05），mDC数量分别为（16．7±6．3）×10^6／L、（28．7±17．6）×10^6／L和（5．5±0．9）×10^6／L（P〈0．05）。低危MDS组、高危MDS组和正常对照组DC占外周血单个核细胞（PBMNC）百分比分别为（2．37±0．53）％、（3．58±1．39）％和（0．68±0．08）％（P〈0．05），pDC占PBMNC百分比分别为（0．82±0．29）％、（0．31±0．06）％和（0．37±0．04）％（P〉0．05），mDC占PBMNC百分比分别为（0．96±0．35）％、（1．51±0．70）％和（0．32±0．05）％（P〈0．05）。低危MDS组、高危MDS组和正常对照组外周血中CD80^＋DC分别为（30．6±11．8）×10^6／L、（2．3±0．9）×10^6／L和（2．3±0．6）×10^6／L（P〈0．05），CD86^＋DC分别为（25．1±7．4）×10^6／L、（12．4±6．3）×10^6／L和（6．2±3．2）×10^6／L（P〈0．05），CD40^＋DC分别为（2．8±1．0）×10^6／L、（1．5±0．9）×10^6／L和（3．2±2．3）×10^6／L（P〉0．05）。结论 MDS患者外周血中DC数量增多、比例异常；以mDC增多为主，pDC无明显增多；MDS患者DC高表达CD80和CD86，CD40表达不增高。提示MDS患者诱导抗肿瘤细胞免疫的抗原呈递细胞（pDC）数量及功能不足；而与正常造血克隆炎性损伤有关的抗原呈递细胞（mDC）却增多。这可能是导致MDS患者细胞免疫异常的重要机制之一。     

不同来源人造血干/祖细胞在NOD/SCID小鼠体内归巢能力的差异

目的 比较不同来源的人造血干／祖细胞在NOD／SCID小鼠体内归巢能力的差异性，并探讨其体内归巢能力与膜表面归巢相关分子CXCR4表达水平的相关性。方法 采用流式细胞术（FACS）检测新鲜脐血、冻存脐血、动员后外周血（mPB）及骨髓来源的CD34^＋细胞表面CXCR4表达水平；将荧光染料CFSE标记的人CD34^＋细胞移植人接受照射的NOD／SCID小鼠，移植后20小时检测已归巢于NOD／SCID小鼠骨髓及脾脏中不同来源的人CD34^＋细胞，计算其相应的骨髓及脾脏归巢效率；并将小鼠股骨制成组织切片，荧光显微镜下观察人CD34^＋细胞在小鼠骨髓腔内的分布。结果 新鲜脐血、冻存脐血、mPB和骨髓CD34^＋细胞膜表面CXCR4表达阳性率分别为（49.52±1．12）％。（46．12±2．29）％，（48．50±2．48）％和（65．39±1．27）％，CD34^＋细胞在NOD／SCID小鼠骨髓的归巢效率分别为（3．00±0．44）％，（2．84±0．46）％，（4．06±0．70）％及（5．76±0．52）％；在脾脏的归巢率分别为（1．88±0．12）％，（1．80±0．15）％，（1．90±0．22）％，（2．16±0．34）％。归巢的CD34^＋细胞主要分布于小鼠股骨的骨内膜区域。结论 脐血CD34^＋细胞膜表面CXCR4水平低于mPB和骨髓。经冻存复苏后脐血CD34^＋细胞膜表面CXCR4水平略有下调。脐血CD34^＋细胞在照射NOD／SCID小鼠的骨髓归巢效率低于mPB和骨髓。     

血清肿瘤标志物联合检测诊断直肠癌价值

目的探讨血清癌胚抗原（carcino-embryonic antigen,CEA）、糖蛋白抗原（carbohydrate antigen,CA）199和CA242联合检测诊断结直肠癌的价值。方法分别采用间接酶联免疫吸附法、电化学发光法、酶免疫荧光法检测健康体检者32名（正常对照组）、良性肠病患者43例（良性对照组）和结直肠癌患者106例（结直肠癌组）血清CEA,CA199,CA242水平,比较3组不同发病部位、不同Dukes分期血清CEA,CA199,CA242水平,并比较3种肿瘤标志物单独或联合检测诊断结直肠癌的阳性率。结果结直肠癌组血清CEA,CA199,CA242水平高于正常对照组和良性对照组（P〈0．01）;结肠癌患者CA19-9水平高于直肠癌患者（P〈0．05）,CEA及CA242水平比较差异无统计学意义（P〉0．05）;Dukes分期D期血清CEA,CA199,CA242水平高于Dukes分期A,B,C期（P〈0．01）;3项肿瘤标志物单项检测诊断结直肠癌阳性率低于联合检测阳性率（P〈0．05）。结论CEA,CA199,CA242联合检测可提高结直肠癌诊断准确率。     

基质细胞衍生因子-1及其受体在G-CSF诱导的造血干/祖细胞动员中的作用

目的探讨基质细胞衍生因子-1（SDF-1）及其特异性受体CXCR4在G-CSF诱导的造血干／祖细胞（HSPC）动员中的作用。方法应用酶联免疫吸附实验（ELISA）、免疫组织化学、流式细胞术等方法检测健康供者稳态及G-CSF动员过程中骨髓、外周血SDF-1／CXCR4的变化，并应用SDF-1中和性抗体阻断BALB／c小鼠SDF-1信号通路，进一步验证SDF-1／CXCR4在动员中的作用。结果G-CSF动员前骨髓和外周血的SDF-1浓度分别为（7．23±0．66）μg/L和（5．43±0．35）μg／L，动员后分别为（5．88±1．03）μg／L和（5．42±0．52）μg/L。动员后骨髓SDF-1蛋白水平下降（P＜0．05），骨髓和外周血之间的SDF-1浓度梯度消失（P＞0．05）；稳态骨髓、动员后骨髓和动员后外周血的CD34^＋ CXCR4^＋细胞在CD34^＋细胞群中的比例分别为（40．98±21．56）％、（65．80±24．68）％和（27．54±26．03）％。动员后CXCR4在骨髓CD34^＋胞上表达增加（P＜0．05），而外周血CD34^＋细胞CXCR4表达降低（P＜0．05）。SDF-1中和性抗体可降低G-CSF动员的BALB／c小鼠外周血成熟白细胞和祖细胞集落数量（P＜0．05）。结论骨髓中SDF-1水平的降低以及CXCR4在HSPC上表达的下降促进了G-CSF介导的动员的发生。     

化疗对晚期结直肠癌患者血清VEGF水平的影响

目的探讨晚期结直肠癌患者化疗前后血清血管内皮生长因子（VEGF）的变化及其与疗效的关系。方法收集48例晚期结直肠癌患者化疗前及化疗4周期后血清,采用ELISA法检测VEGF水平。结果晚期结直肠癌患者外周血清VEGF水平明显高于健康体检者（P〈0．05）;48例晚期结直肠癌化疗后血清VEGF明显下降,化疗前后分别为（434．52±124．34）pg／mL、（384．45±98．95）pg／mL,差别具有统计学意义（P〈0．05）。血清VEGF水平的变化与疗效有关,疗效达CR＋PR者血清VEGF水平化疗后（344．59±93．57）pg／mL比化疗前明显降低（P〈0．05）;疗效为SD＋PD者血清VEGF水平化疗后（417．92±123．53）pg／mL比化疗前略有下降,但差异无统计学意义;疗效达CR＋PR者化疗后血清VEGF水平明显低于疗效为SD＋PD者（P〈0．05）。结论晚期结直肠癌全身化疗能够明显影响血清VEGF水平,动态检测化疗前后血清VEGF水平能反映化疗近期疗效,并可能作为结直肠癌复发转移的重要指标。     

CD4+CD25+调节性T细胞在特发性血小板减少性紫癜患者中的变化

目的探讨CD4^＋CD25^＋T细胞在特发性血小板减少性紫癜（ITP）患者发病机制中的作用。方法应用流式细胞术检测ITP患者外周血CD4^＋CD25^＋T细胞、CD4^＋CD25^highT细胞、CD4^＋FOXP3^＋T细胞、CD4^＋CD25^＋FOXP3^＋T细胞的数量；实时荧光定量PCR检测外周血FOXP3 mRNA的表达水平。将ITP患者和正常人CD4^＋CD25^highT细胞与自身CD4^＋CD25^-T细胞混合培养，检测CD4^＋CD25^high T细胞免疫抑制功能。结果ITP患者外周血中CD4^＋CD25^＋T细胞约占CD4^＋T细胞的（15．64±5．82）％，明显高于正常对照组（9．30±3．95）％（P〈0．01），CD4^＋CD25^high T细胞比例为（1．53±0．66）％，与对照组[（1．36±0．55）％]比较差异无统计学意义（P〉0．05）；CD4^＋FOXP3^＋T细胞和CD4^＋CD25^＋FOXP3^＋T细胞分别为（1．82±1．42）％和（1．25±0．94）％，均明显低于对照组[（3．90±1．37）％和（2．65±0．92）％]（P值均〈0．01）。ITP患者外周血FOXP3 mRNA表达水平较正常人明显下调（P〈0．01），CD4^＋CD25^high T细胞的抑制活性较正常人减弱（P〈0．01）。结论ITP患者中CD4^＋CD25^＋T细胞FOXP3表达水平降低，抑制活性减弱。     

结直肠癌MMP-2的表达与血液微转移的关系

目的从肿瘤的临床病理学和分子病理学角度对结直肠癌组织中MMP-2的表达与肿瘤外周血微转移的关系进行探讨。方法收集了2003年6～12月行根治手术的结直肠癌患者中的30例，行MMP-2免疫组化染色并应用RT-PCR方法检测外周血的转移肿瘤细胞，比较不同MMP-2表达量与血液微转移的关系。结果76．67％结直肠癌患者的肿瘤细胞表达MMP-2（23／30），定位于胞浆，其中弱阳性13例，阳性4例，强阳性6例；MMP-2的表达与肿瘤分期、淋巴转移相关（P〈0．05）。外周血CK20 mRNA表达率为36．7％，外周血CK20 mRNA与结直肠癌分期相关（P=0．004），与肿瘤部位，大体类型，恶性程度无关。结直肠癌组织中MMP-2的表达与结直肠癌患者外周血CK20 mRNA密切相关，随着MMP-2表达的增强外周血CK20 mRNA的阳性率也增加（P=0．002）。结论结直肠癌组织中MMP-2表达的程度不仅能够反映肿瘤的分期，而且能够反映肿瘤血液中微转移的情况。     

外周血STC-1mRNA测定及其在结直肠癌诊断中的价值

目的比较斯钙素（STC-1）mRNA在结直肠癌患者和健康人外周血中表达水平的差异,初步探讨STC-1mRNA作为循环肿瘤标志物的临床意义。方法采用荧光定量逆转录聚合酶链反应（RT—PCR）检测37例结直肠癌患者、18名健康人外周血STC-1mRNA的表达水平,并对其中30例患者的癌胚抗原（CEA）和糖链抗原199（CA199）等血清肿瘤标志物进行比较分析。结果结直肠癌患者与健康人的外周血STC-1mRNA表达水平差异有统计学意义,患者组高于健康组;以受试者工作特征（ROC）曲线分析,发现STC-1mRNA作为结直肠癌诊断指标具有较高的敏感性和特异性,其曲线下面积为0．730;以0．5为表达阳性界值,STC-1mRNA检出结直肠癌的效能优于血清肿瘤标志物CEA和CA199的联合应用。结论应用荧光定量RT—PCR检测结直肠癌患者外周血STC-1mRNA表达水平具有较高的诊断价值,其可能成为新的用于结直肠癌诊断的循环肿瘤标志物。     

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.