T淋巴细胞在脓毒症发病机制中的作用

<正>脓毒症(Sepsis)是宿主对病原体的异常的反应而引起危及生命的器官功能障碍[1]。由于脓毒症的发病机制复杂,虽然人类对脓毒症的认识在不断进步,以抗生素为基础的治疗技术在不断的提高,但全球每年约有1900万新发的脓毒症患者[2],脓毒症的病死率仍高达25%到80%[3]。免疫抑制是脓毒症发病机制中研究最多的机制。T淋巴细胞(T lymphocytes)在脓毒症发病机制中起关键要作用[4]。本文综述T淋巴细胞在脓毒症的发病机制中的作用。     

严重脓毒症并发急性肾损伤的诊治进展

脓毒症常合并急性肾损伤（AKI）在重症医学科尤为常见,病死率高达44%,而未合并AKI患者的病死率为21%,严重威胁患者生命安全［1］。脓毒症并发AKI的发病机制与非脓毒症所致AKI发病机制明显不同。现对脓毒症并发AKI的发病机制及治疗进展进行综述如下。     

脓毒症中细胞免疫紊乱的机制

脓毒症是临床危重患者主要的死亡原因之一,在美国每年约有75万脓毒症患者,其中21.5万患者终因脓毒症而死亡。随着对脓毒症病理生理过程认识的加深和现代分子生物学技术的应用,人们对于脓毒症的发病机制有了更深的了解。大量研究表明,脓毒症的发生与免疫功能紊乱密切相关。因此,深入探讨脓毒症中免疫功能紊乱的病理生理基础,可进一步阐明脓毒症的发病机制,并为其预防和治疗开拓新的思路。     

细胞外组蛋白与脓毒症

脓毒症(sepsis)是指微生物入侵机体感染后引起的全身炎症反应综合征(systemic inflammatory response syndrome,SIRS).国外流行病学调查显示,脓毒症的发病率呈逐年上升的趋势,与1995年相比,2004年脓毒症的发病率和病死率均明显升高口[1].由于脓毒症发病机制复杂,临床救治十分困难,因此对脓毒症的治疗及其发病机制的研究一直是国内外学者关注的焦点.Xu等[2]研究使脓毒症的发病机制及治疗有了新的突破,引入了治疗靶点组蛋白.     

高迁移率族蛋白B1与脓毒症认知功能障碍关系的研究进展

脓毒症幸存者出院后常出现远期的记忆力下降、认知障碍、生活质量下降，甚至死亡等不利结局，给家庭和社会造成极大的经济及精神负担。近年来，脓毒症认知功能障碍越来越成为医学研究关注的热点，高迁移率族蛋白B1（HMGB1）作为关键晚期炎症介质参与了脓毒症发病过程，并且与脓毒症认知功能障碍存在密切关系。但HMGB1介导脓毒症认知功能障碍机制尚不清楚。目前认为其主要通过介导炎症反应及神经炎症，血脑屏障的破坏，氧化应激和小胶质细胞的激活，海马体的炎性损伤四个方面参与脓毒症认知功能损伤。未来亟待进一步探索HMGB1介导脓毒症与脓毒症后认知障碍的确切关系及其具体信号通路，进而为脓毒症及脓毒症认知功能障碍的防治开辟新的干预靶点。     

补体系统的激活对脓毒症心肌病的不利影响

感染、组织损伤、急性炎症反应等都可以激活补体,无论补体从哪条途径被激活,都可能引起继发性的炎症反应和组织器官损伤,导致SIRS、脓毒症和MODS的发生.心脏损伤是严重脓毒症、脓毒性休克时常见的并发症,是造成脓毒症预后不良的重要原因之一.近年来,补体系统过度的激活造成脓毒症心肌细胞损伤的机制已成为脓毒症的一个研究新热点并受到广泛关注.     

脓毒症心肌病发病机制研究进展

脓毒症是机体对感染反应失调引起的危及生命的器官功能障碍综合征,脓毒症心肌病是继发于脓毒症的严重心脏并发症,由机体对感染反应失调引起免疫系统反应紊乱而导致心脏功能障碍、心肌损伤,能显著增加脓毒症的病死率。脓毒症心肌病的发病机制尚不明确,目前已报道的研究指出脓毒症心肌病产生的主要原因有：异常的钙信号、线粒体功能障碍、心肌细胞炎症损伤、血流动力学的改变、氧化应激反应。本文将从以上几点对脓毒症心肌病发病机制进行综述。     

脓毒症与氧化应激损伤研究进展

脓毒症所涉及发病机制相当复杂,氧化性应激损伤可能是重要的发病机制之一。本文对脓毒症时氧自由基在氧化应激的发生、发展中的作用及抗氧化剂的保护机理作一综述。     

C5aR与C5L2在脓毒症中的作用

脓毒症时补体系统过度激活产生大量过敏毒素C5a,C5a与其受体相互作用在脓毒症的发生过程中十分重要,成为研究脓毒症发生机制中的一个新热点.     

脓毒症与机体免疫状态紊乱

脓毒症 (sepsis)是临床危重病人死亡的常见原因。随着人们研究脓毒症致病机制和宿主对脓毒症反应基因学基础的不断深入 ,人们对脓毒症的病理生理机制有了新的认识 ,特别是认识到机体免疫状态紊乱在脓毒症的发生、发展中起到重要作用。1　免疫亢进与脓毒症许多研究认为 ,脓毒症反映了机体难以控制的炎症反应。在感染、损伤和急性炎症时激活的单核巨噬细胞和淋巴细胞可释放大量促炎介质如TNF -α、IL - 1、IL - 6、IL - 12、IL- 18以及IFN -γ。垂体前叶细胞表达TNF和IL - 1的受体 ,炎症介质可通过这些受体激活该细胞释放促肾上腺皮质…     

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.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.     

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.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.