4T超导恒定强磁场对大鼠的急性毒性作用

目的:探讨4T(40000Gs)导恒定磁场对大鼠是否具有急性毒性作用。超方法:实验于2004-03/09于中国科学院电工所超导国家重点实验室和深圳大学生命科学学院微生物基因工程深圳市重点实验室完成。选择成年健康SD大鼠130只,随机分为11组,实验大鼠分为连续处理24,48,72h3个剂量组(n=10),同时设立相应的3个对照组(n=10)。另针对磁场处理72h后,设立脱离磁场12h及1个月检测组(n=10),再设立脱离磁场作用1个月后实验大鼠一般生殖毒性实验组(n=20),并相应设立生殖毒性对照组(n=20)。采用中国科学院电工所研制的超导恒定强磁场,强度为4T。通过观察各组大鼠的一般情况、病理解剖、血液检查及生化指标检测、微核检测、染色体核型分析等,分析4T磁场对实验大鼠是否具有急性毒性作用;并且进一步观察磁场是否具有潜在或慢性生殖毒性。结果:130只大鼠全部进入结果分析,无脱失。①各组大鼠的一般情况及大体病理解剖、血常规检查指标:差异无显著性意义(F=3.14,P>0.05)。②各组大鼠微核实验中嗜多染红细胞在红细胞中所占比率:差异无显著意义(F=2.97P>0.05)。③各组大鼠均无染色体丢失、臂缺损,以及染色体带型变化。④大鼠的生殖毒性实验结果:生殖毒性组与生殖毒性对照组大鼠(雄性)精子畸形数量及形态比较,差异无显著性意义(F=2.62,P>0.05);生殖毒性组与生殖毒性对照组大鼠(雌性)受孕率、着床数、活胎数、死胎数、吸收胎数变化及胎仔雌雄比例、体质量、体长、尾长、囱门宽度比较,差异无显著性意义(F=2.15,P>0.05)。结论:4T超导恒定磁场对实验大鼠无急性毒性作用,目前临床所使用的磁疗强度远低于此,对于生物体是安全的。     

IL-10在大鼠心肌缺血再灌注中的变化及意义

目的探讨大鼠心肌缺血再灌注过程中血清IL-10浓度及意义,为临床诊断IRI提供实验依据。方法将大鼠随机分成假手术组(对照组,n=21),缺血/再灌注(模型组)和甲基强的松龙治疗组(药物组,n=21)3组,每组内再随机分成缺血0.5h(n=7)、再灌注0.5h(n=7)再灌注2h(n=7)三个亚组。在心肌缺血前用甲基强的松龙(30mg/kg)对药物组大鼠预处理。分别测定缺血0.5h、再灌注0.5h及2h血清中IL-10的含量和心肌组织中MPO含量。结果①对照组IL-10无明显变化,模型组与药物组自缺血0.5h、再灌注0.5h至2hIL-10呈逐渐升高趋势,差异具有显著性意义(模型组:F=26.075,P<0.01;药物组:F=39.263,P<0.01),两两比较差异具有显著性意义(P<0.05);各时段内,自对照组、模型组、药物组IL-10明显升高,差异具有显著性意义(缺血0.5h:F=85.383,P<0.05;再灌注0.5h:F=64.923,P<0.01;再灌注2h:F=131.727,P<0.01),两两比较差异具有显著性意义(P<0.05)②对照组心肌组织MPO活性无明显变化;模型组和药物组中,心肌组织MPO含量随着再灌注时间延长而升高,并随着再灌注时间进一步延长而略有降低,差异具有显著性意义;模型组F=4.153,P<0.05;药物组F=8.725,P<0.01);相应时段内,对照组、药物组、模型组差异具有显著性意义(缺血0.5h:F=403.785,P<0.01;再灌注0.5h:F=119.8     

恒定磁场对缺血再灌注脑组织的保护作用

背景:磁疗历史悠久,可用于治疗多种疾病,研究恒磁场对缺血性脑血管病的保护作用能为非药物、无创伤治疗提供新的临床治疗依据,开辟物理因子治疗新途径。目的:观察恒磁场治疗对缺血再灌注损伤大鼠宏观水平的血液流变学、亚细胞水平的红细胞膜流动性、分子水平的抗氧化酶活性以及一氧化氮和一氧化氮合成酶活性的影响。设计:完全随机设计。单位:哈尔滨医科大学生物物理教研室。材料:实验于2002-05/11在哈尔滨医科大学生物物理实验室进行,取40只健康Wistar大鼠适应性喂养1周后随机分成3组,假手术组(n=10)、模型组(n=15只)、磁疗组(n=15只)。方法:①模型组、磁疗组线栓法制作大鼠大脑中动脉缺血再灌注模型,假手术组线栓不阻塞动脉血流。②磁疗组脑缺血后立即将其头颈部置于40mT的恒磁场中30min,1次/d,假手术组和模型组不作暴磁处理。3组大鼠手术7d后麻醉状态下眼球取血、断头取脑。主要观察指标:①观察三组大鼠血液流变学变化。②各组大鼠红细胞膜流动性指标变化。③各组大鼠血清谷胱甘肽过氧化物酶及铜蓝蛋白含量变化。④各组大鼠脑组织丙二醛、一氧化氮、一氧化氮合成酶活性等指标的变化。结果:30只大鼠进入结果分析。①血液流变学指标:模型组全血高切、低切黏度、纤维蛋白原和红细胞压积显著高于假手术组(P<0.01),磁疗组上述指标显著低于模型组(P<0.01)。②红细胞膜流动性指标:模型组荧光偏振度、平均微黏度、各向异性显著高于假手术组(P<0.01),磁疗组上述指标低于模型组(P<0.05)。③模型组大鼠血清谷胱甘肽过氧化物酶及铜蓝蛋白含量显著低于假手术组(P<0.05),磁疗组高于模型组(P<0.01),并略高于假手术组。④模型组大鼠脑组织铜锌超氧化物歧化酶、丙二醛、一氧化氮、一氧化氮合成酶活性均显著高于假手术组(P<0.05或0.01),抗氧化酶活性显著低于假手术组(P<0.01);经过磁场治疗后,磁疗组大鼠各指标均较模型组好转(P<0.05,0.01)。结论:恒定磁场能显著改善大鼠的血液流变学特性,提高红细胞膜流动性及机体的抗氧化酶活力,降低丙二醛、一氧化氮、一氧化氮合成酶含量,提高了机体的抗氧化能力,从而有效地阻止了自由基、一氧化氮对神经组织的损伤,阻断了脑缺血的病理生理过程,对脑缺血再灌注损伤起到一定的保护作用。     

磁场对大鼠脑缺血再灌注后胶质纤维酸性蛋白表达的影响

目的:探讨磁场对大鼠脑缺血再灌注后胶质纤维酸性蛋白(GFAP)表达的影响。方法:线栓法制作大脑中动脉闭塞(MCAO)脑缺血2h再灌注模型。将24只雄性SD大鼠随机分成模型组(n=12)、磁疗组(n=12),每组再分为3d、7d两个亚组,每组6只。磁疗组在缺血再灌注12h后予磁场处理(0—10.5m T,频率50Hz,20min/次,1次/d)。模型组干预过程中除不开机外,其余过程同磁疗组。在治疗3d、7d后(处死前)对大鼠进行神经功能缺损评分(m NSS),脑组织切片采用免疫组织化学染色方法观察脑缺血周围GFAP表达变化。结果:磁疗7d组大鼠m NSS评分较模型组降低(P0.05);磁疗组脑缺血周围GFAP免疫组织化学染色反应阳性细胞计数增加(P0.05)。结论:磁疗可促进大鼠脑缺血再灌注后GFAP的表达,促进脑组织修复。     

还原型谷胱甘肽对脓毒症大鼠心肌组织中Toll样受体4表达的影响

目的:探讨还原型谷胱甘肽(glutathione,GSH)对脓毒症大鼠急性心肌损伤的保护作用及其机制。方法:采用盲肠结扎穿孔术(cecal ligation and puncture,CLP)建立SD大鼠脓毒症致急性心肌损伤模型。按照随机数字表将大鼠随机分为正常组(n=6)、假手术组(n=18)、脓毒症组(n=18)、GSH干预组(n=18)。GSH干预组于CLP术后经尾静脉注射GSH60 mg/kg,共0.1 mL;假手术组和脓毒症组则给予等量0.9%氯化钠溶液。除正常组外,每组大鼠再按术后6 h、12 h、24 h分为3个亚组(每组各6只),各亚组组大鼠在CLP术后相应时间点采集血清及心肌组织标本。所有大鼠均于血标本采集完毕后处死。HE染色观察心肌组织病理改变;采用自动生化分析仪检测血清肌酸激酶同工酶(creatine kinase MB isoenzyme,CK-MB)的水平,采用实时荧光定量逆转录–聚合酶链反应法检测心肌组织Toll样受体4(Toll-like receptor 4,TLR4)的mRNA表达。结果:与假手术组及正常组比较,脓毒症组大鼠术后6 h血清CK-MB水平和心肌组织TLR4 mRNA表达开始升高,12 h达到高峰,24 h仍明显升高,差异有统计学意义(P0.05),且术后24 h心肌组织HE染色显示肌纤维结构排列疏松紊乱,间质充血水肿,见大量炎性反应细胞浸润等损伤性改变;与脓毒症组比较,GSH干预组大鼠术后6 h血清CK-MB水平和心肌组织TLR4 mRNA表达已有所下降,术后12 h、24 h明显下降,差异均有统计学意义(P0.05),且术后24 h时心肌组织上述病理学损伤性改变也明显减轻。结论:心肌组织TLR4 mRNA的高表达在脓毒症致急性心肌损伤中起着重要的作用,而在脓毒症早期应用GSH干预可抑制心肌组织TLR4 mRNA的表达,对脓毒症致急性心肌损伤有保护作用。     

IL-10在大鼠心肌缺血再灌注中的变化及意义

目的探讨大鼠心肌缺血再灌注过程中血清IL-10浓度及意义,为临床诊断IRI提供实验依据.方法将大鼠随机分成假手术组(对照组,n=21),缺血/再灌注(模型组)和甲基强的松龙治疗组(药物组,n=21)3组,每组内再随机分成缺血0.5h(n=7)、再灌注0.5h(n=7)再灌注2h(n=7)三个亚组.在心肌缺血前用甲基强的松龙(30mg/kg)对药物组大鼠预处理.分别测定缺血0.5h、再灌注0.5h及2h血清中IL-10的含量和心肌组织中MPO含量.结果①对照组IL-10无明显变化,模型组与药物组自缺血0.5h、再灌注0.5h至2h IL-10呈逐渐升高趋势,差异具有显著性意义(模型组:F=26.075,P＜0.01;药物组:F=39.263,P＜0.01),两两比较差异具有显著性意义(P＜0.05);各时段内,自对照组、模型组、药物组IL-10明显升高,差异具有显著性意义(缺血0.5 h:F=85.383,P＜0.05;再灌注0.5 h:F=64.923,P＜0.01;再灌注2h:F=131.727,P＜0.01),两两比较差异具有显著性意义(P＜0.05)②对照组心肌组织MPO活性无明显变化;模型组和药物组中,心肌组织MPO含量随着再灌注时间延长而升高,并随着再灌注时间进一步延长而略有降低,差异具有显著性意义;模型组F=4.153,P＜0.05;药物组F=8.725,P＜0.01);相应时段内,对照组、药物组、模型组差异具有显著性意义(缺血0.5h:F=403.785,P＜0.01;再灌注0.5h:F=119.811,P＜0.01;再灌注2h:F=428.932,P＜0.01).③心肌再灌注期间,血清IL-10与MPO表现出相平行的反方向变化趋势,经统计处理显示二者间存在显著性负相关(r=-0.649,P＜0.01).结论在大鼠心肌缺血再灌注中,甲基强的松龙可促进内源性IL-10大量释放;IL-10可间接显示炎症反应的程度.     

帕病1号方对帕金森病模型大鼠的神经保护作用

目的探讨帕病1号方颗粒对帕金森病(PD)模型大鼠发挥神经保护作用的机制。方法采用6-羟基多巴胺纹状体两点注射法造成左侧纹状体损毁模型大鼠,把造模成功的40只大鼠分为3组:模型组(n=12),高剂量组(n=14),低剂量组(n=14)。另加正常组(n=8)。高、低剂量组每天分别给予帕病1号方颗粒18 g/kg,9 g/kg,模型组、正常组均予等体积蒸馏水。32 d后,行旋转测试;测定大鼠左侧纹状体匀浆中超氧化物歧化酶(SOD)活性及谷胱甘肽(GSH)、丙二醛(MDA)含量,免疫组化法检测中脑黑质P-Akt(ser 473)、Bcl-2、Bax表达。结果治疗后,与同期模型组相比,高、低剂量组旋转行为学明显改善(P<0.01),且存在量效关系(P<0.01)。与同期模型组相比,高剂量组SOD活性(P<0.01)和GSH含量明显提高(P<0.01),MDA含量降低(P<0.01);低剂量组GSH含量提高(P<0.01),MDA含量降低(P<0.01);与低剂量相比,高剂量组GSH含量提高(P<0.01),MDA含量降低了(P<0.01)。与模型组相比,高、低剂量组P-Akt(ser 473)、Bcl-2、Bax阳性细胞数及Bc1-2/Bax比值有显著性差异(P<0.05),且存在量效关系(P<0.05)。结论帕病1号方颗粒能提高大鼠抗氧化能力和清除自由基能力,同时激活Akt信号转导通路,发挥其神经保护作用。其神经保护作用呈一定的量效关系。     

肝X受体激动剂对C57/BL6小鼠大脑C型1类尼曼-匹克蛋白表达的影响

目的:研究肝X受体(LXR)激动剂T0901317对C57/BL6小鼠大脑C型1类尼曼-匹克蛋白(NPC1)表达和胆固醇流出的影响.方法:C57/BL6小鼠被随机分成3组,对照组(n=13)给予赋型剂灌胃;处理1组(n=13)给予T0901317(10 mg/kg)灌胃;处理2组(n=13)给予T0901317(20 mg/kg)灌胃.通过高效液相色谱法测定大脑胆固醇含量;采用逆转录聚合酶链反应、蛋白质印迹和免疫组化方法分别检测大脑组织NPC1 mRNA和蛋白质表达.结果:两处理组小鼠大脑胆固醇含量明显少于对照组(P<0.05),其NPC1mRNA和蛋白质表达较对照组明显增高(P<0.05).结论:T0901317减少大脑胆固醇含量可能与其上调NPC1表达有关.     

番红花素促进烧伤大鼠的创面愈合与减轻疼痛

目的:研究番红花素对烧伤大鼠的创面愈合与疼痛影响。方法:将80只大鼠随机分成假烧伤组(n=16),烧伤模型组(n=16),烧伤+10 mg/kg番红花素组(n=16),烧伤+50 mg/kg番红花素组(n=16),烧伤+200 mg/kg番红花素组(n=16)。使用在干浴中预热至165℃的铜块(2 cm×2 cm,150 g)构建大鼠皮肤全厚度烧伤。采用HE染色观察组织学恢复情况,检测不同处理组大鼠的机械阈值和热阈值,蛋白质印迹法和ELISA方法检测创面皮肤组织中诱导型一氧化氮合酶(iNOS)和炎性因子IL-6和TNF-α的表达。结果:番红花素的应用可以促进创面皮肤伤口愈合并减轻疼痛。且番红花素抑制创面皮肤组织中iNOS的表达和炎性因子IL-6和TNF-α水平。这一疗效在应用200 mg/kg的剂量时最为明显。结论:番红花素可以促进烧伤大鼠的创面愈合并减轻疼痛。     

葛根素对烫伤大鼠早期心肌组织丙二醛、髓过氧化物酶的影响

目的观察葛根素对严重烫伤大鼠早期心肌组织丙二醛(MDA)、髓过氧化物酶(MPO)变化的影响。方法Wistar大鼠88只随机分为正常对照组(n=8)、复苏组(n=40)、治疗组(n=40),并在后两组中复制30%体表面积Ⅲ度烫伤动物模型。在烫伤后1、3、6、12和24h分别在各组中观察心肌组织MDA及MPO含量。电镜下观察组织学形态变化。结果(1)在复苏组中,心肌组织MDA及MPO含量在伤后1h著显升高(P＜0．01),均在伤后12 h达高峰。(2)在治疗组中,上述指标变化与复苏组趋势相同。但与复苏组相比在伤后1、3、6、12 h显著降低(P＜0．05或P＜0．01)。(3)电镜显示,伤后24 h,治疗组心肌组织损伤程度较复苏组减轻。结论葛根素能抑制严重烫伤大鼠心肌组织MDA及MPO的生成,对烫伤早期心肌损伤有保护作用。     

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.     

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.     

Prospects for the control of neglected tropical diseases by mass drug administration

The prospects for the control of neglected tropical diseases, including soil-transmitted helminthiasis, shistosomiasis, lymphatic filariasis, onchocerciasis and trachoma, through mass drug administration, are exemplified by the elimination of the trachoma as a public-health problem in Morocco. In spite of this and other striking successes, mass drug administration programs are faced with major challenges resulting from suboptimal coverage and lack of efficacy. At current suboptimal coverage rates, programs may need prolongation for an extended period, increasing costs and undermining sustainability. Community participation through health education and information appears to be crucial to improve coverage and to achieve sustainability. Implementation of complementary measures, such as vector control, improved hygiene and environmental sanitation, are important to further control transmission and to prevent re-emergence of the infection and, again, may only be achieved effectively through community-based initiatives. To reduce costs and to relieve pressure on the health system, combining neglected tropical disease programs in areas where diseases coexist and integration with existing control programs for malaria, tuberculosis and HIV/AIDS is advocated. The risk of developing drug resistance is of particular concern in view of the lack of alternative drugs, and reduced treatment efficacy due to emerging resistance is evident for the soil-transmitted helminths and onchocerciasis. Given the risk for the development of drug resistance and the need for a high degree of participation, close attention should be paid to the monitoring of the coverage and efficacy of the different program components.     

Bacterial meningitis: an update of new treatment options

The outcome of bacterial meningitis critically depends on the rapid initiation of bactericidal antibiotic therapy and adequate management of septic shock. In community-acquired meningitis, the choice of an optimum initial empirical antibiotic regimen depends on the regional resistance patterns. Pathogens resistant to antibacterials prevail in nosocomial bacterial meningitis. Dexamethasone is recommended as adjunctive therapy for community-acquired meningitis in developed countries. In comatose patients, aggressive measures to lower intracranial pressure <20 mmHg (in particular, external ventriculostomy, osmotherapy and temporary hyperventilation) were effective in a case–control study. Although many experimental approaches were protective in animal models, none of them has been proven effective in patients. Antibiotics, which are bactericidal but do not lyse bacteria, and inhibitors of matrix metalloproteinases or complement factor C5 appear the most promising therapeutic options. At present, vaccination is the most efficient method to reduce disease burden. Palmitoylethanolamide appears promising to enhance the resistance of the brain to infections.     

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.     

Imaging choices in occult hip fracture

Background: Hip fracture is a common injury, with an incidence rate of > 250,000 per year in the United States. Diagnosis is particularly important due to the high dependence on the integrity of the hip in the daily life of most people. Objectives: In this article we review the literature focused on hip fracture detection and discuss advantages and limitations of each major imaging modality. Discussion: Plain radiographs are usually sufficient for diagnosis as they are at least 90% sensitive for hip fracture. However, in the 3–4% of Emergency Department (ED) patients having hip X-ray studies who harbor an occult hip fracture, the Emergency Physician must choose among several methods, each with intrinsic limitations, for further evaluation. These methods include computed tomography, scintigraphy, and magnetic resonance imaging. Conclusion: We present an evidence-based algorithm for the evaluation of a patient suspected to have an occult hip fracture in the ED. Also outlined are future directions for research to distinguish more effective techniques for identifying occult hip fractures.     

Systematic Reviews Published in the April 2012 Issue of the Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD but monthly online. The April 2012 issue (second DVD for 2012) contains 5045 complete reviews, 2182 protocols for reviews in production, and 17,084 short summaries of systematic reviews published in the general medical literature. In addition, there are citations of 674,000 randomized controlled trials, and 15,400 cited papers in the Cochrane methodology register. The health technology assessment database contains just over 11,000 citations. One hundred and seventeen new reviews have been published in the last 3 months of which 12 have potential relevance for practitioners in pain and palliative medicine. The impact factor of the Cochrane Library stands at 6.186. Readers are encouraged to access the full report for any articles of interest as only a brief commentary is provided.     

Platelets,thrombosis, coagulation,and atherosclerosis

When I first got the invitation to join a medical delegation going to Moldova, I thought for a moment that our destination was the fictional country in the old Marx Brothers movie Duck Soup. On further checking, it turns out that entertaining place was called Freedonia. I now know that Moldova is indeed a real country, bordered on the west by Romania and on the other three sides by the Ukraine. It is a proud country, rich with traditions, and its people are warm, giving, eager to learn ways to improve their healthcare system, and deeply appreciative of our attempts to help them in the task.