血小板冰冻后功能变化及临床应用研究

目的 探讨血小板冰冻后功能变化及临床应用,并试图探讨血细胞冰冻的个体化依据.方法 将不同浓度的二甲基亚砜(DMSO)作为保护剂加入血小板中,在--80℃条件下冰冻,观察冰冻前后凝血及收缩块形成过程,检测冰冻前后及不同离心条件下血小板计数、血浆中血小板第3因子(PF3)、第4因子(PF4)、血小板体积分布宽度(PDW)及P-选择素(CD62P)对血小板的聚集、黏附、血块收缩功能的影响.对质控条件合格的冰冻血小板单独或合并新鲜血小板的临床应用进行回顾性分析.结果 血小板阻断后血液不凝集;5 ％DMSO与2％DMSO做保护剂冰冻血小板的血浆凝固时间、血块收缩时间及血块收缩功能(血浆析出率)的差异均无统计学意义(P＞0.05),但1％DMSO做保护剂的冰冻血小板的上述各项指标与5％DMSO做保护剂的血小板的差异均有统计学意义(P＜0.05);各样本随着离心次数的增多,所取上清血浆中血小板计数越低,但血浆凝固时间也越短,血块凝固效果越差,离心1次和离心2次后上清血浆的凝固时间、凝固效果的差异均有统计学意义(P＜0.05),1％ DMSO做保护剂的冰冻血小板的上述各项指标与5％DMSO做保护剂的血小板的差异也有统计学意义(P＜0.05);1％DMSO做保护剂的冰冻血小板无凝块形成,将其离心并用新鲜血浆代替上清液后,血块收缩现象又重新出现.2％ DMSO做保护剂与5％DMSO做保护剂的样本中血小板计数、PDW、血浆中PF3、PF4及CD62P等各项指标的差异有统计学意义(P＜0.05).冰冻血小板和新鲜血小板搭配应用与单独新鲜血小板临床效果的差异有统计学意义(P＜0.05).结论 血小板冰冻后血浆凝固时间明显缩短,且与血小板破坏程度有关,血小板破坏越严重,血浆凝固时间越短;但血块收缩时间明显延长,血小板破坏程度越严重,血块收缩时间越长;血块的凝固质量随着血小板的破坏增加而变差;血小板破坏后释放出的PF3、PF4、CD62P对血小板功能有促进凝集和抑制收缩两方面的影响.冰冻血小板和新鲜血小板搭配应用效果较好;可用低浓度2％ DMSO进行冻存.     

二甲基亚砜(DMSO)对血小板体外聚集功能的影响

目前,DMSO冰冻保存血小板作为22±2℃液体保存血小板的补充产品,在外科手术应用中已取得良好的临床疗效[1].然而冰冻血小板仍缺乏统一的质量标准[2],而且现有体外功能测定并不一定能完全反映其在体内发挥功能的实际情况[3].必须寻求能如实反映血小板体内功能的指标及简便易行的质量控制方法才能控制生产工艺,提供质量可靠的冰冻血小板制品.为此,笔者通过检测花生四烯酸诱导的DMSO终浓度不同的液体血小板体外聚集功能,进一步分析讨论了聚集功能作为DMSO冰冻保存血小板质量控制的指标是否合适?现将结果报告如下.     

冰冻保存对机采血小板释放5-HT的影响

目的 观察冰冻保存对机采血小板释放5-HT 的影响.方法 常规以二甲基亚砜(DMSO)为冷冻保护剂、-80 ℃冰冻保存机采血小板30 d;采用全自动血细胞分析仪检测并比较冰冻保存前后血小板计数(PLT)、血小板平均体积(MPV)和血小板体积分布宽度(PDW);ELISA法检测冰冻前后及在阳离子没食子酸丙酯(C-PG)、凝血酶(thrombin,THB)、二磷酸腺苷(ADP)、胶原(Collagen)等不同PLT诱导剂激活作用下PLT释放5-HT的数量.结果 冰冻复苏后机采血小板计数变化不大(P>0.05),但MPV和PDW 均增加,血小板制品血浆5-HT含量也显著增高(P<0.01).在不同诱导剂作用下,新鲜血小板释放5-HT均高于冰冻保存的血小板,差异有显著性(P<0.01).结论 (1)机采血小板冰冻保存与解冻过程中,会引起血小板膜形态和生物活性改变.(2)冰冻保存后PLT对不同诱导剂的反应下降.     

鲎试剂用于DMSO中热原的检测

长期以来二甲基亚砜(DMSO)一直作为实验室中组织细胞冰冻保存的保护剂。近年来DMSO作为血小板冰凉保护剂在临床上的应用愈来愈多，目前在输注前，并未去除DMSO，故其安全性逐步引起人们的重视。笔用鲎试剂(TAL)作为一种快速的内毒素检测方法，对冰冻保护剂DMSO中热原进行检测，现报告如下。     

不同浓度二甲亚砜深低温保存实验犬血小板相关参数变化研究

目的 研究不同浓度二甲亚砜深低温保存实验犬血小板相关参数变化。方法 应用2%和5%二甲亚砜浓度对实验犬血小板进行-80℃深低温保存1～180 d不等,解冻后观察血小板计数(PLT)、平均血小板体积(MPV)、血小板压积(PCT)、血小板分布宽度(PDW)、血小板糖蛋白-Ib(GP-Ib)、血小板选择素(P-Selectin)、血小板因子-4(PF4)及β-血小板球蛋白(β-TG)变化情况。结果 应用2%二甲亚砜浓度和5%二甲亚砜浓度分别深低温保存血小板,保存前后PLT、PCT、GP-Ⅰb、P-Selectin、PF4、β-TG变化均不明显(P0.05);而MPV、PDW则有不同程度变化(P0.05)。随着深低温保存血小板时间的延长,在1～180 d内除PLT外MPV、PCT、PDW、GP-Ib、P-Selectin、PF4、β-TG分别具有不同程度变化(P0.05)。另外,2%二甲亚砜浓度进行深低温保存血小板的PLT、MPV、PCT、PDW、GP-Ib、P-Selectin、PF4、β-TG分别与5%二甲亚砜浓度进行深低温保存血小板比较无明显区别(P0.05)。结论 在180 d内对实验犬血小板进行2%和5%二甲亚砜浓度深低温保存,对PLT、MPV、PCT、PDW、GP-Ib、P-Selectin、PF4、β-TG相关指标二者间无明显区别。为了减少残留DMSO量导致临床动物试验各种结果影响,推荐可应用2%二甲亚砜浓度进行实验犬血小板深低温保存。     

冰冻血小板收缩功能与P-选择素的相关性研究

目的研究冰冻血小板收缩功能与血浆及血小板表达P-选择素（CD62P）的关系,进一步探讨血小板止血功能及机制。方法用1％、2%、5％等不同浓度的DMSO作保护剂,对血小板进行冰冻,对冰冻后的样本检测其聚集功能、粘附功能,并对样本血浆中的CD62P含量和冰冻后血小板表达CD62P的百分比进行检测,观察血浆凝固时间、血小板聚集、粘附功能与血浆中及血小板表达CD62P的含量的关系。结果随着血浆中CD62P含量的增高和冰冻后血小板表达CD62P百分比的增加,血小板聚集功能逐渐减弱,血浆凝固时间明显缩短。结论随着冰冻保护剂浓度的降低,血小板破环增加,表达CD62P的百分比增加,聚集功能减弱。     

深低温保存血小板的功能变化及新特性的研究

目的明确血小板冰冻保存后功能指标的变化并对冰冻血小板新亚群的产生和其新特性进行初步探讨。方法对冰冻保存前后的单采血小板进行回收率、黏附率、聚集强度和血小板第3因子(PF3)活性进行检测,同时采用流式细胞术比较分析不同保存条件下单采血小板膜表面功能分子表达变化的差异。结果冰冻保存后的回收率(%)为70.94±15.48,黏附率(%)为34.03±10.07,聚集强度(%)为53.82±12.73,PF3活性为(17.81±1.68)s。冰冻血小板CD62p再表达率(%)为51.8±7.7,根据表达和再表达CD62p能力不同可分为三个亚群,新鲜血小板CD62p再表达率(%)为98.4±0.6。结论冰冻保存后的单采血小板仍具有良好的功能活性,且血小板通过冰冻保存后产生了新亚群。新亚群膜表面功能分子的变化可能与即刻止血功能增强有关。     

采集后6小时与72小时制备的冰冻单采血小板质量研究

目的通过比较采集后6h和72h制备的冰冻单采血小板制品的多项质量参数，为冰冻单采血小板的制备标准提供依据。方法以美国产Trima血细胞分离机配套全密闭7d保存袋采集的单采血小板，分别于采集后6h和72h制备为冰冻血小板制品，1周后复苏留样，分别检测血小板计数（PLT，MPV，PCT，PDW）、血小板粘附性、血小板P选择蛋白、PF3A、PF4、pH值、血块收缩试验（血浆法）。结果采集后6h和72h制备的冰冻单采血小板，两者相比差异无统计学意义（t〈0．01，P〉0．05）。单采血小板在不同保存条件下，PF3A均保持了良好的PF3活性，单采血小板在常规或冰冻保存条件下，PF4及P选择蛋白的表达均明显增加，采集后6h和72h制备的冰冻单采血小板相比，差异无统计学意义（t〈0．01，P〉0．05）；单采血小板在常规保存3d内，粘附功能和血块收缩试验没有明显变化，而冰冻保存的单采血小板这两项指标呈明显减退现象，血小板的活力下降明显。结论以美国产Trima血细胞分离机配套全密闭7d保存袋采集的单采血小板，分别于采集后6h和72h制备的冰冻血小板制品，两者的体外指标分析结果相比差异无显著性，且都能有效的改善和控制急性大出血患者的出血倾向，用于抢救急性大出血患者疗效是可靠的。     

去除白细胞和保存温度对用6%DMSO冰存3年的血小板的影响

背景 6％的DMSO冰冻PLT能够在-80℃存放2年,而 5％的 DMSO 冰冻血小板能够在-150℃存放 3年。-80℃下的冰冻血小板衰老更快,也许是由于粒细胞的存在。作者考查去除白细胞和保存温度对DMSO冰冻血小板的影响及-80℃和-135℃的保存温度对 PVC塑料袋破损量的影响。研究设计及方法 单采富血小板血浆(PRP)分为等量的 2份,一份去除白细胞,另一份不过滤分为等量的2份。用6％的DMSO冰冻在-80℃和-135℃下用PVC塑料袋存放3年。结果 -     

应用小剂量第2信使调节剂混合物冰冻保存血小板的体外功能研究

目的探讨应用小剂量第2信使调节剂混合物[thrombosol(TS):250μmol/L阿米洛利、50μmol/L硝普钠、100μmol/L腺苷和2%二甲基亚砜(DMSO)]冰冻保存血小板的体外功能变化。方法新鲜浓缩血小板应用终浓度2%DMSO、1×TS或2%DMSO+1/2TS中浓度的阿米洛利和硝普钠为冰冻保护剂-80℃保存,分别在冰冻前,冻存1周、1个月、3个月和6个月复温后,检测Plt、平均血小板体积(MPV)、凝血酶诱导的聚集反应、血小板表面CD42b、CD62p和CD63分子改变。结果2%DMSO+1/2TS中浓度的阿米洛利和硝普钠冰冻保存血小板的Plt、凝血酶诱导的聚集反应和CD42b表达水平明显高于2%DMSO组(P<0.05或<0.01),CD62p和CD63表达显著低于2%DMSO组(P<0.05或P<0.01),所有检测结果均与TS组血小板差异无统计学意义(P>0.05),而且随冰冻保存时间的延长无明显改变(P>0.05)。结论2%DMSO+1/2TS中浓度的阿米洛利和硝普钠冰冻保存6个月血小板的体外功能与TS冰冻保存血小板相当。     

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.     

Interprofessional approaches to creating safe,high quality health care

Three supplementary perspectives are presented arguing that interprofessional collaboration is both necessary and desirable. Nonetheless, there are often too many serious intra-professional barriers and obstacles to interprofessional collaboration to make it successful. Some of these barriers, it is argued and illustrated, are found in the multiple ways in which professional identity is tacitly acquired and embodied in the practitioners' habitual, everyday practice. The paper then explores ways in which reflection, especially Second order reflection, can help to elucidate and overcome these obstacles, as well as increasing professional adaptability and competence.     

Systematic Reviews Published in the January 2011 Issue of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online. The January 2011 issue (first quarterly DVD for 2011) contains 4515 complete reviews, 1985 protocols for reviews in production, and 13,521 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 641,000 randomized controlled trials, and 14,018 cited papers in the Cochrane methodology register. The health technology assessment database contains over 9300 citations. One hundred and seven new reviews have been published in the last 3 months, of which five have potential relevance for practitioners in pain and palliative medicine.     

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.     

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.     

Prise en charge des entorses externes de cheville : étude clinique préliminaire sur l’efficacité du dispositif Myolux™

Ankle sprains are the most common injury of the musculoskeletal system and are associated with significant societal and economic impacts. It has been proven that classical therapeutic strategies may not be effective in preventing recurrent injuries: the recurrence rates reported in the literature can reach 73%. In order to provide an effective rehabilitation solution, a destabilizing orthosis was developed. This device is equipped with a mechanical articulator reproducing the subtalar mechanics and placed under the heel. In this paper, we present the main results of a preliminary clinical study conducted between 2004 and 2007. All subjects included in this study were treated with the abovementioned orthosis during 10 rehabilitation sessions of 30 minutes each. Data show a relatively low recurrence rate of 12% for the overall population. Moreover, it's of primary importance to note that this satisfactory ratio is largely reduced (3% of recurrence rate) for the 29 patients who performed one training session per month after the 10th initial rehabilitation sessions. Hence, the destabilizing orthosis appears to be an effective solution to prevent recurrent ankle sprains. However, joint protection requires long-term and regular training sessions. This result has motivated the development of a similar device allowing patients to perform training sessions at home. Finally, data obtained in this study are promising awaiting the final results of the comparative, multicentric and independent clinical trials currently managed by the Hospices Civils de Lyon.