一例Fechtner综合征临床与分子缺陷研究——附文献复习

目的对1例Fechtner综合征先证者及其家系进行临床与实验室研究并检测非肌性肌球蛋白重链9基因（MYH9）突变。方法采用瑞特染色观察先证者及其家系患者的外周血涂片血小板和中性粒细胞的特殊形态；透射电镜观察先证者血小板及中性粒细胞的超微结构。从先证者及其家系成员外周血白细胞中提取基因组DNA，PCR扩增MYH9的40个外显子及侧翼内含子序列，检测其基因突变。结果该家系中Fechtner综合征患者表现为血小板减少、巨大血小板、中性粒细胞包涵体，伴或不伴遗传性肾炎。先证者及其家系患病成员的MYH9改变为外显子40第5981位核苷酸C-T杂合改变，使第1933位密码子CGA（编码Arg）突变为终止密码TGA。结论国内首次报道Fechtner综合征家系。MYH9（外显子40）R1933X杂合改变是导致Fechtner综合征的原因。     

一例May-Hegglin异常家系临床及分子生物学研究

目的　探讨May Hegglin异常 (MHA)患者的血小板改变及其分子遗传学特征。 方法　对先证者及其家系成员的静脉血 ,分别进行机数和镜数血小板计数 ,观察血小板形态 ,以流式细胞术分析血小板膜蛋白 ,ELISA法检测血小板膜抗体 ,用聚合酶链反应 (PCR)技术扩增先证者及其父亲非肌性肌球蛋白重链 9基因 (MYH 9)的 2 5 ,30 ,38,4 0号外显子 ,分析PCR产物的核苷酸序列 ,确定突变点 ,用间接免疫荧光结合细胞核染色技术显示粒细胞中的包涵体 (D hle小体 )。结果　患者机数血小板数明显低于镜数血小板数 ,巨大血小板占 90 %以上 ,血小板膜糖蛋白 (CD4 1、CD6 1、CD4 2a、CD4 2b)均在正常范围内 ,膜抗体未能检测到 ,血小板功能正常 ,MYH 9基因 38号外显子第 5 5 2 1位核苷酸存在G→A杂合突变 (GAG→AAG) ,从而导致其编码的非肌性肌球蛋白重链A(NMMHC A)第184 1位谷氨酸变为赖氨酸 ,正常对照及家系中正常者未见此突变 ,MHA患者中性粒细胞胞浆中荧光分布显示了“梭形”包涵体的形态和轮廓。结论　MYH 9基因点突变并伴有血小板减少和巨大血小板是MHA的主要特征。     

一个May-Hegglin异常家系MYH9基因突变新位点研究

目的 鉴定一个May-Hegglin异常家系MYH9基因突变位点.方法 报告一个May-Hegglin异常家系的临床及实验窜检查资料,包括外周血和骨髓瑞姬染色涂片的细胞形态学检查,静脉血检测肝、肾功能,血小板功能、血块退缩时间及凝血功能,用PCR技术扩增先证者及其母亲的MYH9基因1、10、25、30、38、39、40号外显子,用直接测序的方法 分析PCR产物的核苷酸序列.结果 先证者及其母亲均有巨大血小板、血小板减少和粒细胞内包涵体,2位患者肝、肾功能,血小板功能、血块退缩时间及凝血功能均正常.此家系患者存在30号外显子第4270位碱基G>A突变,使第1424位密码子由GAC>AAC.编码的氨基酸由天冬氨酸转变为天门冬酰胺.而正常对照者无此突变.结论 该May-Hegglin异常家系存在30号外显子上Asp1424Asn突变,此突变为中国人May-Hegglin异常家系的首次报道.     

1例非肌性肌球蛋白重链9基因相关疾病家系并文献复习

目的鉴定1例非肌性肌球蛋白重链9(MYH9)基因相关疾病家系的致病突变。方法调查收集先证者和家系成员病史资料,观察其临床特征和实验室检查指标。采用芯片捕获高通量测序方法检测先证者MYH9基因,确定突变位点后,对先证者和家系成员进行Sanger验证。结果该家系三代4名患者均有鼻衄、瘀斑紫癜、外伤血肿或月经量增多病史,长期存在镜下血尿和蛋白尿。血涂片镜检均有血小板减少、巨大血小板和粒细胞异常包涵体"三联征"。所有患者MYH9基因第40内含子供体剪接位点存在错义突变c.5765+2TA(p.R1922Rfs*43),且该基因突变与疾病表型共分离。结论该家系存在MYH9基因c.5765+2TA(p.R1922Rfs*43)剪接突变,是MYH9基因相关疾病的致病突变,为国内首次报道。     

Fechtner综合征异常家系的临床与分子缺陷

  目的  分析一先天性血小板减少症家系的临床、实验室特点, 并探讨其分子发病机制。  方法  收集该家系成员的临床资料, 采集先证者及其家系成员的静脉血, 分别进行全自动及人工血小板计数; 显微镜下观察血小板形态; 流式细胞术分析血小板膜蛋白; 透射电镜观察中性粒细胞胞浆包涵体。聚合酶链反应扩增非肌性肌球蛋白重链9基因(non-muscle myosin heavy chain9gene, MYH9)的40个外显子, 分析PCR产物的核苷酸序列, 并直接测序确定突变位点。  结果  镜下观察外周血涂片巨大血小板占90%以上, 血小板膜糖蛋白(CD41、CD61、CD42a、CD42b)均在正常范围内, 血小板功能正常; 中性粒细胞胞浆透射电镜可见无包膜分隔的包涵体, MYH9基因38号外显子第5521位核苷酸存在G→A杂合突变(GAG→AAG), 从而导致其编码的非肌性肌球蛋白重链A(NMMHC2A)第1841位谷氨酸变为赖氨酸, 正常对照及该家系正常者未见此突变。  结论  MYH9基因点突变并伴有血小板减少及巨大血小板是Fechtner综合征的主要特征。     

一个May-Hegglin异常家系临床及实验室特征分析

May-Hegglin异常是非肌性肌球蛋白重链9(Nonmuscle myosin heavy chain 9 gene,MYH9)基因突变相关疾病中的一种,为常染色体显性遗传性血小板减少合并中性粒细胞包涵体,常易误诊.我们发现一个May-Hegglin异常家系,现报道如下.     

高分辨率熔解曲线分析在血友病B F9基因突变检测中的应用

目的 利用高分辨率熔解曲线(HRM)技术建立简便有效的血友病B(HB)基因诊断的方法.方法 收集2005年1月至2010年6月就诊于上海瑞金医院的55例HB患者的外周血标本,抽提外周血基因组DNA.采用PCR扩增结合测序的方法对40例HB患者进行F9基因突变检测,利用其中21例带有F9基因1～7号外显子突变的HB患者标本建立相应的HRM突变筛查方法.采用F9基因1～7号外显子的PCR-HRM突变筛查方法及8号外显子的DNA直接测序方法,对15例未知F9基因突变的HB患者进行基因诊断.结果 通过PCR扩增结合测序,40例HB患者均检测到F9基因突变.21例带有F9基因1～7号外显子突变的HB患者标本中,19例(90％)患者的突变可通过PCR-HRM技术进行检测.通过F9基因1～7号外显子PCR-HRM突变筛查及8号外显子的DNA直接测序,15例未知F9基因突变的HB患者均检测到F9基因突变.55例HB患者中共检测到34种F9基因突变.结论 HB基因诊断的新方法,即PCR-HRM筛查F9基因1～7号外显子突变结合8号外显子的DNA测序法操作简便、结果可靠.     

中国人群肥厚型心肌病患者心肌肌钙蛋白T基因突变研究

目的初步探讨中国人群肥厚型心肌病患者心肌肌钙蛋白 T基因突变情况,为该病的早期防治和康复介入奠定理论基础. 方法提取 58例肥厚型心肌病( hypertrophic cardiomyopathy, HCM)患者外周血白细胞基因组 DNA,聚合酶链反应( PCR)扩增心肌肌钙蛋白 T( cTnT)基因 8、9、11号外显子,产物做单链构象多态性( SSCP)分析,出现异常条带者直接测序验证. 结果58例临床确诊的 HCM患者 cTnT基因 8, 9, 11号外显子,除 160位密码子存在 ATC和 ATT多态性外,未发现基因位点的异常. 结论与国外报道的肥厚型心肌病约 20%是由肌钙蛋白 T基因突变引起相比较,中国人群肥厚型心肌病患者基因突变可能存在不同的特点.     

非肌球蛋白重链9相关疾病大家系患者中性粒细胞包含体特点分析

目的分析一非肌球蛋白重链9相关疾病（MYH9-RD）大家系患者中性粒细胞包涵体的形态和结构特点,阐明MYH9-RD中性粒细胞包涵体形成的特点,以探讨MYH9-RD中性粒细胞包涵体的致病机制。方法应用光学显微镜（瑞姬染色）和电子显微镜观察中性粒细胞包涵体形态和超微结构特点;应用间接免疫荧光复染技术观察MYH9-RD患者与正常对照者之间非肌性肌球蛋白IIA（NMMHC—IIA）在胞浆中的分布情况。结果光学显微镜和电子显微镜下可见中性粒细胞中明显的包涵体,形态多样,大多位于细胞边缘;间接免疫荧光复染技术显示患者和正常人之间NMMHC—IIA在中性粒细胞中的分布有差异,中性粒细胞胞浆中存在明显绿色荧光的包涵体,其形态和轮廓与瑞一姬氏染色显示的包涵体形状、大小基本一致,但更为清晰;正常对照的粒细胞胞浆中未见包涵体。结论光学显微镜和电子显微镜进一步确认了家系患者包涵体的存在。免疫荧光技术显示患者和正常人之间NMMHC—IIA在中性粒细胞中的分布有差异;MYH9-RD患者中性粒细胞包涵体的主要构成成份是NMMHC—IIA;包涵体的形态结构复杂多样可能与本家系临床表型复杂多样有关,该家系对进一步揭示MYH9-RD的致病机制具有重要的意义。     

1个表皮松解性掌跖角化症家系角蛋白9基因检测及产前诊断

目的分析1个表皮松解性掌跖角化症(epidermolytic palmoplantar keratoderma, EPPK)家系角蛋白9(keratin 9, KRT9)基因突变情况,并进行产前诊断。方法收集EPPK家系6例患者及家系所有表型正常成员外周血,提取DNA,采用PCR扩增KRT9基因第1～7外显子,并采用Sanger法进行基因测序检测KRT9基因突变。明确KRT9基因突变后,采集先证者羊水进行产前诊断并随访。结果 6例患者均检测到KRT9基因第1外显子存在c.487CT(p.R163W)杂合突变,该突变可导致其编码的第163位精氨酸被色氨酸代替(p.R163W),家系中表型正常成员该位点均无突变;先证者羊水产前诊断结果示胎儿未携带致病突变c.487CT,新生儿出生后随访12个月,未见EPPK表型。结论 KRT9基因c.487CT(p.R163W)杂合突变是该EPPK家系的致病机制,基因诊断和产前诊断可有效降低生育患病儿的风险。     

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.