腺苷不参与大鼠双后肢缺血预处理对移植胰的保护作用

目的探讨腺苷是否参与了大鼠双后肢缺血预处理对移植胰保护作用的信号传导机制。方法18只糖尿病大鼠随机分为缺血再灌注组（I／R组，n＝6）；缺血预处理组（IPC组，n＝6）和缺血预处理＋8-环戊基-1，3-二丙基黄嘌呤（DPCPX）组（IPC＋DPCPX组，n＝6），各组大鼠均行胰腺移植。检测各组再灌注前、后血糖，再灌注后2h血清中肿瘤坏死因子（TNF）-α、胰腺组织中髓过氧化酶（MPO）和丙二醛（MDA）含量，并利用TUNEL法检测移植胰凋亡细胞。结果再灌注后I／R组血糖、TNF-α，胰腺组织凋亡指数（AI）、MPO和MDA含量均显著高于IPC组（P〈0．01）和IPC＋DPCPX组（P＜0．01），IPC＋DPCPX组与IPC组再灌注后各项指标无显著性差异（P〉0．05）。结论大鼠双后肢肢缺血预处理对大鼠移植胰的缺血再灌注损伤具有保护作用，腺苷与这种保护作用无关。     

NF-κB 在大鼠肝缺血再灌注损伤与缺血预处理保护机制中的作用

目的：探讨NF-κB在大鼠肝缺血再灌注损伤与缺血预处理（ IPC ）保护机制中的作用。方法将72只SD雄性大鼠随机分成4组：缺血再灌注损伤组（ I/R组）;缺血预处理组（ IPC组）;NF抑制剂组（应用二硫代氨基甲酸吡咯烷即PDTC组）;假手术组（S组）。测定血清丙氨酸氨基转移酶（ALT）,天冬氨酸氨基转移酶（ AST）,乳酸脱氢酶（ LDH）活性;测定肝脏的湿干比（ W/D）;经HE切片染色后,观察肝组织显微结构;分别应用免疫组化和Western blot免疫印迹法测定肝组织中的TNF-α和NF-κB表达。结果 I/R组大鼠血清肝酶学指标（ AST、ALT、LDH）和肝脏的组织形态学都显示较S组大鼠有明显的肝脏损伤。同时肝组织W/D比值和TNF-α的阳性表达比及NF-κB在免疫组化和western blot免疫印迹中的表达亦均明显高于S组（ P＜0.01）。 IPC组和PDTC组大鼠肝损伤程度明显轻于I/R组,同时TNF-α和NF-κB在两种检测方法中的表达亦均明显低于I/R组（ P＜0.05）。结论 NF-κB在肝I/R损伤的发生机制中是细胞信号传导通路上的重要转录因子,对I/R损伤的炎症反应起介导作用;NF-κB的活化被抑制是肝IPC保护机制中的重要环节;针对NF-κB的靶向治疗是临床肝保护有意义的新途径。     

山莨菪碱抗肝脏缺血再灌注损伤的实验研究

目的　探讨山莨菪碱对大鼠肝脏缺血损伤的保护作用及其机制。方法　测定大鼠肝脏缺血再灌注(模型组)和预防性应用山莨菪碱(预防组)时胆汁流量、肝组织丙二醛(MDA)含量及肝脏组织学改变和中性粒细胞浸润程度。结果　预防组与模型组相比,胆汁流量显著增加(P＜0.01),MDA含量显著降低(P＜0.01),预防组肝脏组织学变化较轻,白细胞浸润较少。结论　山莨菪碱具有对肝脏缺血再灌注损伤明显的保护作用,其作用机制可能是抑制自由基的产生。     

腺苷预处理对缺血/再灌注心肌细胞凋亡和凋亡蛋白Bcl-2/Bax的影响

目的 研究腺苷预处理对大鼠缺血/再灌注心肌细胞凋亡和凋亡蛋白Bcl-2/Bax的影响.方法 制备缺血/再灌注损伤(I/R)和腺苷预处理的大鼠模型,采用流式细胞仪检测心肌细胞凋亡率和凋亡蛋白Bcl-2和Bax.结果 ①缺血/再灌注组和腺苷组心肌细胞凋亡率均显著高于对照组(P<0.01),而腺苷组凋亡率显著低于缺血/再灌注组(P<0.01).②缺血/再灌注组抗凋亡蛋白Bcl-2表达与对照组比较无明显差别,而腺苷组Bcl-2显著高于缺血/再灌注组和对照组(P<0.01);缺血/再灌注组和腺苷组促凋亡蛋白Bax表达显著高于对照组(P<0.01),而腺苷组Bax低于缺血/再灌注组(P<0.01);缺血/再灌注组和腺苷组Bcl-2/Bax比值显著低于对照组(P<0.01),而腺苷组Bcl-2/Bax比值显著高于缺血/再灌注组(P<0.01).结论 腺苷预处理明显抑制大鼠缺血/再灌注后心肌细胞的凋亡,并使Bcl-2/Bax比值增加.     

乌司他丁对大鼠缺血-再灌注肝脏Toll样受体表达的影响

目的 观察乌司他丁对大鼠肝脏缺血-再灌注损伤以及缺血肝叶Toll样受体2(TLR2)表达的影响.方法 SD大鼠36只,随机分为假手术组、缺血-再灌注组(I/R组)及乌司他丁组.于再灌注120 min后采集标本,测定血清ALT、AST,取缺血-再灌注肝叶组织,测定组织超氧化物歧化酶(SOD)及丙二醛(MDA)活性,实时定量PCR法测定TLR2表达水平.结果 乌司他丁组大鼠血清ALT、AST和肝组织MDA水平低于I/R组(P ＜0.05);肝组织SOD水平高于I/R组(P＜0.05);再灌注后TLR2表达水平明显升高,而乌司他丁组TLR2表达低于I/R组(P＜0.05).结论 乌司他丁可以对部分肝叶缺血引起的再灌注损伤有保护作用,其机制可能为抑制TLR2的表达.     

异氟醚预处理对缺血/再灌注复合内毒素大鼠肝脏损伤的影响

目的 观察再灌注期腹腔注射内毒素脂多糖(LPS)对大鼠肝脏缺血/再灌注(I/R)损伤的影响以及异氟醚(ISO)预处理的干预作用.方法 将32只SD大鼠随机均分为4组:假手术(Sham)组、单纯肝脏I/R组、肝脏I/R复合LPS损伤(I/R+LPS)组及ISO预处理组.I/R+LPS组吸氧预处理后间隔0.5 h进行肝脏缺血1 h、再灌注4 h,再灌注开始时腹腔内注入LPS;ISO预处理组以ISO吸入预处理0.5 h,间隔0.5 h后进行I/R损伤操作,再灌注开始时腹腔内注入LPS.再灌注4 h处死各组动物,留取肝脏及血液标本;观察各组肝组织病理学改变,血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、肿瘤坏死因子-α(TNF-α)的变化以及肝组织TNF-α、髓过氧化物酶(MPO)活性的改变.结果 与Sham组比较,损伤各组血清ALT、AST、TNF-α及肝组织TNF-α、MPO活性均显著升高(P均＜0.01);与I/R组比较,I/R+LPS组肝脏损伤和炎症细胞因子反应明显较重(P＜0.05或P＜0.01)l与I/R+LPS组比较,ISO预处理组肝脏的病理损伤明显较轻,血清ALT、AST、TNF-α水平及肝组织MPO活性和促炎细胞因子TNF-α的表达水平均显著降低(P均＜0.05).结论 再灌注期复合LPS腹腔注射明显加重了肝脏的损伤和炎症细胞因子反应,ISO预处理可明显减轻复合损伤介导的炎症反应,保护肝脏.     

腺苷预处理对缺血-再灌注心肌细胞凋亡及核因子-κB表达的影响

目的　研究腺苷预处理对大鼠心肌细胞凋亡及核因子 κB(NFκB)表达的影响。方法　制备缺血再灌注损伤 (I/ R组 )和腺苷预处理 (AP组 )的大鼠模型 ;采用原位缺口末端标记法 (TUNEL)检测心肌细胞凋亡 ,免疫组织化学方法检测心肌组织 NFκB表达。结果　 AP组大鼠心肌细胞凋亡率〔(2 6 35 .0±316 .0 ) %〕及心肌组织中 NFκB的表达〔(33.2 1± 16 .91) %〕明显低于 I/ R组〔(5 0 13.0± 5 0 3.7) %和 (5 9.30± 10 .36 ) % ,P <0 .0 5和 P <0 .0 1〕,明显高于对照组 ,分别为 (6 8.7± 5 0 .3) %和 (10 .98± 4 .6 5 ) % ,P均 <0 .0 1。结论　腺苷预处理具有明显降低大鼠缺血再灌注后心肌细胞凋亡的作用 ,可能与腺苷预处理减轻缺血再灌注心肌组织过度表达 NFκB有关。     

川芎嗪大鼠肝脏/肾脏缺血再灌注损伤中P-选择素表达的影响

目的研究川芎嗪对肝脏/肾脏缺血再灌注损伤中对P-选择素、肝脏组织MPO和NF-κB活性表达的影响。方法建立大鼠肝脏、肾脏缺血再灌注损伤模型,全自动生化分析仪检测再灌注后肝脏、肾脏功能,光镜下观察肝脏、肾脏病理学变化,和以免疫组化法检测肝脏肾脏组织中P-选择素的表达情况,肝脏组织MPO和NF-κB活性表达的情况。结果川芎嗪处理后肝、肾功能不全程度明显减轻,且肝肾组织中P-选择素表达减少(P0.05),肝脏组织MPO和NF-κB活性表达均明显降低(P0.05)。结论在肝脏/肾脏缺血再灌注过程中P-选择素、肝脏组织MPO和NF-κB活性表达的增高,是通过介导中性细胞向肝、肾组织中浸润聚集而在肝脏/肾脏缺血再灌注损伤中发挥重要作用。川芎嗪可以减轻肝脏/肾脏缺血再灌注损伤程度,其机制可能是抑制肝肾组织中P-选择素、肝脏组织MPO和NF-κB活性的表达。     

血塞通预处理对心肌缺血再灌注损伤的早期保护作用

目的观察血塞通预处理对大鼠心肌缺血再灌注(I/R)损伤的早期保护作用,并研究其可能机制.方法采用开胸冠状动脉结扎建立缺血再灌注模型,25只雄性SD大鼠随机分为假手术组,缺血再灌注组(I/R组),缺血预处理组(IPC组),血塞通预处理组(PNS预处理组).再灌注后2 h测定各组血清肌酸磷酸激酶-MB(CK-MB)含量以及心肌细胞凋亡情况和心肌细胞Bcl-2和Bax蛋白的表达,并观察心肌超微结构变化.结果IPC组及PNS预处理组血清CK-MB均明显低于I/R组(P＜0.05).IPC组及PNS预处理组TUNEL阳性细胞数,Bax阳性细胞数均明显低于I/R组(P＜0.05).和I/R组相比,IPC组及PNS预处理组心肌超微结构损伤减轻.结论PNS预处理后心肌细胞凋亡减少,心肌细胞损伤减轻,对I/R损伤产生有和缺血预处理类似的早期保护作用.     

亚低温缺血预处理对鼠缺血/再灌注肠组织Bcl-2和Bax蛋白表达的影响

目的 探讨亚低温缺血预处理(MHIP)对大鼠缺血/再灌注损伤(I/R)肠组织Bcl-2和Bax蛋白表达的影响。方法 将32只大鼠随机分为4组(每组8只):假手术对照组(sham)、缺血/再灌注组(I/R)、缺血预处理组(IP)、亚低温预处理组(MHIP)。观察各组肠组织超微结构及Bcl-2、Bax蛋白表达。结果 肠缺血/再灌注后小肠组织Bcl-2和Bax蛋白表达光密度值明显增高,与假手术对照组有显著性差异(P<0.01);缺血预处理组与缺血/再灌注组比较及亚低温预处理组与缺血预处理组比较小肠组织Bcl-2蛋白表达光密度值增高(P<0.01,P<0.05),Bax蛋白表达光密度值降低(P<0.01,P<0.05),Bcl-2/Bax光密度比值明显增高。结论 缺血预处理可通过上调Bcl-2基因的蛋白表达与下调Bax基因的蛋白表达,抑制肠缺血/再灌注诱导的细胞凋亡以保护缺血再灌注肠损伤,亚低温能增强缺血预处理的保护作用。     

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.     

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.     

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.     

Modified micro-superior percutaneously-assisted total hip: early experiences & case reports

Because of the extensile nature and familiarity of the standard posterior-lateral approach to the hip, a family of "micro-posterior" approaches has been developed. This family includes the Percutaneously-Assisted Total Hip (PATH) approach, the Supercapsular (SuperCap) approach and a newer hybrid approach, the Supercapsular Percutaneously-Assisted Total Hip (SuperPATH) approach. Such approaches should ideally provide a continuum for the surgeon: from a "micro" (external rotator sparing) posterior approach, to a "mini" (external rotator sacrificing) posterior approach, to a standard posterior approach. This could keep a surgeon within his comfort zone during the learning curve of the procedure, while leaving options for complicated reconstructions for the more practiced micro-posterior surgeons. This paper details one author's experiences utilizing this combined approach, as well as permutations of this entire micro-posterior family of approaches as applied to more complex hip reconstructions.     

Structure and function of "metalloantibiotics"

Although most antibiotics do not need metal ions for their biological activities, there are a number of antibiotics that require metal ions to function properly, such as bleomycin (BLM), streptonigrin (SN), and bacitracin. The coordinated metal ions in these antibiotics play an important role in maintaining proper structure and/or function of these antibiotics. Removal of the metal ions from these antibiotics can cause changes in structure and/or function of these antibiotics. Similar to the case of "metalloproteins," these antibiotics are dubbed "metalloantibiotics" which are the title subjects of this review. Metalloantibiotics can interact with several different kinds of biomolecules, including DNA, RNA, proteins, receptors, and lipids, rendering their unique and specific bioactivities. In addition to the microbial-originated metalloantibiotics, many metalloantibiotic derivatives and metal complexes of synthetic ligands also show antibacterial, antiviral, and anti-neoplastic activities which are also briefly discussed to provide a broad sense of the term "metalloantibiotics."