预冻技术参数对血小板冻干保存的影响

本研究采用正交设计方案探讨冻结速率、退火速率、退火温度和退火持续时间4个预冻条件参数对血小板冻干保存的影响．冻干血小板再水化后的数值恢复率、细胞形态和结构、血小板活化和聚集力等指标分别用血细胞计数计、扫描电子显微镜、3色流式细胞仪及对凝血酶的聚集反应进行检测并综合评价．结果显示：在不同的预冻条件组合方式下，冻干血小板的数值恢复率在（91．3％-53．5）％范围内；实验各组血小板冻干制品的冰晶大小和形状有所不同；冻干再水化血小板的活化标记物PAC-1和CD62p的表达和分布与新鲜血小板较为接近，其中PAC-1表达率均维持在较低水平（0．03％-0．22％），而各组样本CD62p的表达水平存在差异．实验中根据血小板数值恢复率得到预冻条件的最佳理论组合是A2B1C1D3，即将血小板悬液先以20℃／min的速率冻结至-40℃维持2小时。再以1．5℃／min对搁板升温至-30℃后维持0．5小时，最后进入冻干程序直至结束。结论：冻结速率、退火速率、退火温度和退火持续时间对冻千血小板的数值恢复率均有作用，预冻条件参数的不同组合方式影响血小板冻干保存效果．     

冷冻干燥保存血小板的实验研究

本研究探讨冷冻干燥保存血小板的方法,以获得可长期冻干保存的血小板制品,使之能在常温条件下保存、占用空间小、重量轻、便于长距离运输,能够满足突发事件和战伤救治的需要。在冷冻干燥保存过程中添加血小板可逆性激活抑制剂、DMSO和海藻糖等低温保护剂,进行预处理、冷冻、一级干燥、二级干燥,再水化,并同时测定血小板回收率,凝血酶聚集反应,促凝血功能,CD62p表达率和PAC-1表达率等。结果表明:血小板回收率为56.29%,其对凝血酶的聚集反应与对照组无明显差异,对ADP和丙基没食子酸诱导的聚集反应较对照组分别降低49.34%和26.25%,促凝血功能与对照组比较也无统计学差异;冻干血小板CD62p表达率为42.36%,PAC-1表达率为2.12%,凝血酶激活后CD62p再表达率为50.88%,PAC-1再表达率为54.55%。结论:添加血小板可逆性激活抑制剂,海藻糖和DMSO后的冻干血小板,其聚集活性和促凝血功能与新鲜血小板无明显差异,血小板可逆性激活抑制剂降低了冻干血小板的CD62p表达,增强了冻干血小板的生存能力,因而延长了其生存时间,因此可以该冻干方法为基础进一步提高冻干保存血小板的效率。     

人冻干血小板复水程序的优化

目的探讨不同复水条件对冻干血小板功能的影响。方法经过添加激活抑制剂(PGE1、左旋精氨酸、植酸钠和百维利肽)、DMSO和海藻糖等低温保护剂、冷冻干燥后获得冻干血小板,在一系列不同复水程序下对冻干血小板复水,应用流式仪检测并分析其CD62p和PAC-1的表达,评价血小板活化状态。通过正交设计,研究不同复水程序包括复水溶液、复水温度、复水方式3个影响因素对冻干血小板复水后活性的影响。结果 3个对冻干血小板复水后活化的影响因素排序:复水温度>复水方式>复水液(P<0.05);37℃条件下冻干血小板复水后血小板膜蛋白CD62p和PAC-1活化率最低,分别为(5.96±2.51)%和(4.55±1.97)%;预水化后再行四步添加复水可降低冻干血小板膜蛋白CD62p和PAC-1的表达率至(6.68±2.62)%和(5.45±2.06)%;添加聚乙烯吡咯烷酮(PVP)和血小板抑制剂的2号复水液对冻干血小板复水后膜蛋白CD62p和PAC-1的表达率影响最低,分别为(6.72±3.35)%和(5.28±2.30)%。总体模型评价进一步显示,第5实验组,即在37℃条件下加入PVP和血小板抑制剂的复水液配方,先预水化后再行四步法添加复水,其复水血小板活化率最低,CD62p和PAC-1的表达率分别为(3.06±1.36)%和(2.70±0.84)%。结论 37℃下,饱和蒸汽环境中预水化后,采用加入PVP及血小板抑制剂的复水液四步添加复水,其复水血小板活化率最低。     

冻干再水化血小板结构与功能研究

目的探索血小板冻干保存及再水化后结构与功能的改变。方法选择过期的冻干再水化血小板为实验对象,以新鲜血小板作为对照,分别用血小板计数仪、扫描电镜、透射电镜、血小板聚集仪和三色流式细胞仪检测血小板的回收率、稳定性、形态、超微结构、聚集反应和膜表面糖蛋白的表达。结果实验组血小板计数明显下降,血小板回收率为49.36%,且随着血小板放置时间的延长,血小板回收率逐渐下降,血小板透光性较差,分泌颗粒数目较少。实验组凝血酶、ADP、胶原及瑞斯托霉素的最大聚集率均与对照组有明显统计学差异（P〈0.05）。凝血酶作用后CD62p再表达率为44.02%,显著低于对照组70.31%（P〈0.05）,PAC-1再表达率为38.90%,显著低于对照组65.28%（P〈0.05）。结论过期血小板冻干再水化后的恢复率较低,稳定性较差,结构和功能均低于新鲜血小板,但冻干再水化血小板仍具有一定的活性,为新鲜血小板的冻干保存提供了基础。     

冻干血小板功能的体外评价

目的评价冻干血小板的体外功能。方法将经过可逆性激活抑制、添加DMSO和海藻糖等低温保护剂、冷冻干燥后获得的血小板再水化,与新鲜血小板比较,应用流式仪检测分析其CD62p和PAC-1的表达,评价血小板活化状态和血小板反应能力;应用APACT检测诱导剂诱导的血小板最大聚集率并用SPAT评价血小板聚集和促凝血活性;应用扫描电镜和透射电镜技术研究血小板的形态和超微结构的变化。结果经过血小板激活抑制剂和冻干保护剂预处理的冻干血小板,再水化后对凝血酶的最大聚集率(79.0%)与对照组(86.2%)差异无统计学意义(P>0.05),对ADP和没食子酸诱导的聚集反应比对照分别降低49.34%和26.25%;经凝血酶激活后CD62p再表达率为50.88%略低于对照组70.32%(P<0.05),PAC-1再表达率为54.55%与对照组63.38%无明显差异;促凝血功能SPAT检测结果69.4 s与对照组70.6 s差异无统计学意义(P>0.05)。结论经过冷冻干燥保护剂和血小板激活抑制剂预处理后获得的冻干血小板,体外聚集活性和促凝血功能接近新鲜血小板。     

冻干血小板聚集和活化的实验研究

目的了解血小板在冻干前、后功能活性的变化。方法应用流式细胞仪检测冻干复水(再水化)血小板及未冷冻干燥血小板胞膜CD61、CD62p、PAC-1的分子表达,评价冻干复水后血小板活化状态;应用血小板聚集仪检测通过诱导剂瑞斯托霉素、二磷酸腺苷诱导的血小板最大聚集率,分析冻干血小板复水后血小板聚集率变化。结果血小板冻干保护剂渗透压值为(2 055.6±123.8)m OSmol/kg;冻干前及复水后血小板分布宽度(PDW)(%)分别为15.50±3.05、18.29±0.55,MPV(f L)分别为9.01±1.84、8.63±0.58;冻干血小板复水回收率(%)为81.57±12.57;冷冻前及复水后血小板最大聚集率(%)分别为34.30±33.14、22.10±23.25;冷冻前及冻干复水后血小板胞膜CD61分子表达(%)分别为43.17±13.55、48.64±13.24,CD62p分子表达(%)分别为17.34±6.47、9.79±4.48,PAC-1分子表达(%)分别为4.92±6.32、4.22±4.64。结论冷冻前及复水后血小板最大聚集率的变化甚微,冻干复水后血小板仍具仍具有一定的存活能力;冷冻前及冻干复水后血小板胞膜CD61、CD62p和PAC-1分子表达略有变化(P0.05)。     

冻干血小板保护液优化的实验研究

目的优化冻干血小板保护液,减少冻干过程对血小板的损害,有效保护其功能。方法采用3因素3水平的正交设计法,对血小板膜保护剂、血小板激活抑制剂、蛋白质类保护剂的3类成分组成的保护液进行优选。检测血小板最大聚集率、血小板活化标志PAC-1、CD62P的阳性表达率和血小板回收率,通过比较其差异,筛选出本实验的最优冻干血小板保护液。以优化保护液对血小板处理后进行冻干,并以此为实验组,与新鲜血小板和原保护液处理后冻干血小板进行比较验证,验证指标与优选指标相同,比较3者4项指标之间的差异。结果正交设计试验结果显示:血小板最大聚集率组间最高(74.33±24.01)%,血小板活化标志PAC-1和CD62P低于9组平均水平,血小板回收率高于9组平均水平。以主要体现血小板功能的血小板最大聚集率为优先指标,结合其余3项检测指标进行综合分析,在原保护液的基础上,筛选出添加了2%DMSO、第2信使调节剂、2 mmol/L维生素B6,75%的PPP保护液组为最优组合。验证实验结果显示,优化保护液组血小板最大聚集率(76.12±6.02)%,与原保护液组相比,差异有统计学意义(P0.05),与新鲜血小板组相比,差异没有统计学意义(P0.05)。最优保护液组血小板激活标志PAC-1和CD62P阳性表达率分别为(3.23±0.49)%和(36.83±8.21)%,2者与原保护液组、新鲜血小板组相比,差异无统计学意义(P0.05);最优保护液组冻干血小板复水化后血小板回收率为(85.90±2.24)%,与原保护液组相比,差异无统计学意义(P0.05)。结论本实验优化的血小板保护液优于原保护液,明显提高了冻干血小板复水化后最大聚集率,能更好地保护血小板的功能,但对血小板冻干过程的保存损害问题没有得到更好的改善,有待下一步深入研究。     

机采血小板保存期内活化分析及临床意义

目的通过分析机采血小板在保存期内的活化水平,探讨其对临床血小板输注效果的影响。方法用流式细胞仪三色免疫荧光标记法对30份机采血小板保存前、保存后d1、d3、d5活化指标PAC-1、CD62P进行检测,ELISA法检测同时点Solube CD62P含量及变化。结果随着保存时间延长,流式分析结果显示血小板PAC-1、CD62P表达率水平显著升高(P<0.05),ELISA法检测sCD62P含量也显著增高(P<0.05)。结论随着保存时间延长,血小板活化水平显著增高,可能在影响血小板临床输注效果中具有重要意义。     

二甲亚砜对血小板冻存中功能保护作用的实验研究

本研究探讨二甲亚砜（DMSO）对血小板冻干保存中激活的抑制作用。以CD62p和PAC-1表达作为血小板的激活标志，CD62p和PAC-1再表达和血小板最大聚集率作为评价血小板功能的指标。对血小板经离心、洗涤及海藻糖负载等顸处理过程中加与不加DMSO的实验组，分别进行血小板膜表面糖蛋白CD62p和PAC-1表达及再表达的流式细胞术（FCMs）分析，血小板最大聚集率和血小板平均体积（MPV）的测定，研究DMSO对血小板激活抑制作用的可逆性。结果显示，血小板经预处理后，不含DMSO组的CD62p和PAC-1表达率显著增高，分别达30．37％和15．01％；含DMSO的组，CD62p表达率为10．72％，PAC．1几乎不表达（0．11％），显著低于不含DMSO组（P〈0．01）。DMSO稀释后，血小板CD62p再表达为54．39％，显著低于对照组（71．69％）和高于不含DMSO组（35．98％）（P均〈0．01）；PAC-1再表达率为49．28％，与对照组（54．48％）无显著差异，显著高于不含DMSO组（P〈0．叭）。在含DMSO组，血小板用原血浆稀释后，血小板聚集功能恢复，对restocetin，thrombin和propylgallate诱导的血小板聚集率分别为92．76％，91．24％和89．66％，与对照组和无DMSO组比无显著性差异，对ADP诱导的聚集率有34．33％，显著高于无DMSO组（P〈0．01），但仍显著低于对照组（P〈0．01）。结论：DMSO对体外处理所致的血小板膜表面CD62p和PAC-1表达具有抑制作用，且该抑制作用是可逆的，DMSO稀释后血小板仍具有CD62p和PAC．1表达能力和聚集反应功能，提示DMSO具有抑制激活损伤和低温保护的双重功能，这一生物学特性使DMSO在血小板的冻干保存中发挥重要作用。     

冻干保存血小板可逆性抑制激活的实验研究

目的探索最优的血小板激活抑制剂组成方案,以建立一套完善的血小板冻干前处理程序。方法选择已基本确定有效作用浓度的6种血小板激活抑制剂如前列腺素E1、腺苷、左旋精氨酸、植酸钠、百维利肽和西洛他唑,结合血小板冷冻干燥保护剂的负载过程,以CD62p、PAC-1、MPV和P lt作为血小板活化指标,CD62p和PAC-1的再表达率作为血小板反应性指标,诱导剂诱导的血小板最大聚集率和SPAT作为血小板聚集和促凝血功能的指标;采用正交实验设计,分8个实验组,研究分析各因素在负载中对血小板状态和功能的影响,选择最优的负载液组成。结果A因素(负载环境)水平Ⅰ在抑制血小板MPV增大、D62p和PAC-1的表达以及再表达率保留、血小板最大聚集率和SPAT影响均优于水平Ⅱ(P均<0.05);B因素(PGE1)C因素(左旋精氨酸)F因素(植酸钠)G因素(百维利肽)的水平Ⅱ则均由于各自的水平Ⅰ。因此,在8个实验条件中,以第3实验组(A1B2C2D1E1F2G2)对血小板功能保护的最好。结论在血小板冻干前保护剂负载过程程序,在血浆负载环境中添加1μmol/L前列腺素E1,5 mmol/L左旋精氨酸,0.5 mmol/L植酸钠和0.5μmol/L百维利肽,可有效抑制血小板激活,使保存的血小板具有表达CD62p和PAC-1活性、聚集反应和促凝血活性。     

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.     

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.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.     

Molecular characterization of virulence and antimicrobial resistance profile of Shigella species isolated from children with moderate to severe diarrhea in northeastern Brazil

Molecular characterization of virulence and antimicrobial resistance profiles were determined for Shigella species isolated from children with diarrhea in Fortaleza, Brazil. Fecal specimens were collected along with socioeconomic and clinical data from children with moderate to severe diarrhea requiring emergency care. Shigella spp. were isolated by standard microbiological techniques, and we developed 4 multiplex polymerase chain reaction assays to detect 16 virulence-related genes (VRGs). Antimicrobial susceptibility tests were performed using disk diffusion assays. S. flexneri and S. sonnei were the predominant serogroups. S. flexneri was associated with low monthly incomes; more severe disease; higher number of VRGs; and presence of pic, set, and sepA genes. The SepA gene was associated with more intense abdominal pain. S. flexneri was correlated with resistance to ampicillin and chloramphenicol, whereas S. sonnei was associated with resistance to azithromycin. Strains harboring higher numbers of VRGs were associated with resistance to more antimicrobials. We highlight the correlation between presence of S. flexneri and sepA, and increased virulence and suggest a link to socioeconomic change in northeastern Brazil. Additionally, antimicrobial resistance was associated with serogroup specificity in Shigella spp. and increased bacterial VRGs.     

护理干预对面部中重度寻常型痤疮的临床疗效影响分析

目的研究护理干预对面部中重度寻常型痤疮的临床疗效影响。方法选取本院在2014年4月~2016年7月诊治的136例面部中重度寻常型痤疮患者,随机分为研究组与对照组,每组68例;所有患者均依据其情况给予对应的治疗,其中对照组在治疗期间给予常规护理,研究组在对照组的基础上再给予综合性护理干预,比较两组的治疗效果及护理满意度情况等。结果患者在接受治疗和护理后,研究组中度与重度患者的治疗效果较对照组均明显提高(P0.05),研究组护理满意度较对照组明显增高(P0.05)。结论对面部中重度寻常型痤疮患者在其治疗期间给予综合性护理干预,具有良好的效果。