Hyperbaric oxygen treatment prevents nitric oxide‐induced apoptosis in articular cartilage injury via enhancement of the expression of heat shock protein 70

Heat shock proteins (HSPs), inflammatory cytokines, nitric oxide (NO), and localized hypoxia‐induced apoptosis are thought to be correlated to the degree of cartilage injury. We investigated the effect of hyperbaric oxygen (HBO) on (1) interleukin‐1β (IL‐1β)‐induced NO production and apoptosis of rabbit chondrocytes and (2) healing of articular cartilage defects. For the in vitro study, RT‐PCR and Western blotting were performed to detect mRNA and protein expressions of HSP70, inducible NO synthase (iNOS), and caspase 3 in IL‐1β‐treated chondrocytes. To clarify that the HSP70 was necessary for anti‐iNOS and anti‐apoptotic activity by HBO, we treated the cells with an HSP70 inhibitor, KNK437. For the in vivo study, cartilage defects were created in rabbits. The HBO group was exposed to 100% oxygen at 2.5 ATA for 1.5 h a day for 10 weeks. The control group was exposed to normal air. After sacrifice, specimen sections were sent for examination using a scoring system. Immunohistochemical analyses were performed to detect the expressions of iNOS, HSP70, and caspase 3. Our results suggested that HBO upregulated the mRNA and protein expressions of HSP70 and suppressed those of iNOS and caspase 3 in chondrocytes. KNK437 inhibited the HBO‐induced downregulation of iNOS and casapase 3 activities. The histological scores showed that HBO markedly enhanced cartilage repair. Immunohistostaining showed that HBO enhanced HSP70 expression and suppressed iNOS and caspase 3 expressions in chondrocytes. Accordingly, HBO treatment prevents NO‐induced apoptosis in articular cartilage injury via enhancement of the expression of heat shock protein 70. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 376–384, 2013     

Effects of Heat on Fragility and Morphology of Human and Calf Erythrocytes

It is important to know the species differences when data from animal experiments are interpreted for human application. This in vitro study focused on the effects of heat, a major concern in mechanically actuated artificial heart development, on the physiology of human and calf erythrocytes (RBC). RBC from calves and healthy human donors were incubated at 25, 37, 46, 48, 50, or 52°C for 1 h. Osmotic fragility was tested and morphological changes were then observed by scanning electron microscopy. The osmotic fragility of human and calf RBC increased at and above 50°C. After incubation at 50°C, 6% of human and 1 % of calf RBC hemolyzed. Changes in surface morphology, which included spherocytic or echinocytic for MS, were observed in 97% of human and 19% of calf RBC after incubation at 50°C. In conclusion, human RBC showed greater changes in osmotic fragility and morphology at and above 50°C. These changes, however, were not observed in either species after 1 h incubation at 46°C.     

HF-Electro-Surgery, Ultrasound-Dissection or Laser for the Laparoscopic Cholecystectomy and for Liver-Wedge-Resection. An Experimental Study in Pigs

laparoscopic wedge-resection of the liver is performed in 6 pigs, in three of these a cholecystectomy is carried out during the same operation. The method of resection chosen was: Monopolar HF-current, ultrasound and laser (Nd:YAG-laser and Holmium:YAG-laser). The least damage to the healthy liver tissue was seen using the Holmium:YAG-laser. Healing (after18 days) was best when the Holmium:YAG-laser had been used. Cautery was worst in both tissue damage and delayed healing.     

姜黄素对干热环境热射病大鼠肾损伤及细胞凋亡的影响

目的探讨姜黄素对干热环境热射病大鼠肾脏损伤的病理变化及细胞凋亡的影响。 方法SPF级成年健康雄性SD大鼠50只，在SPF级环境适应性饲养1周，按随机数字表法分为5组：常温对照组、干热对照组、姜黄素低浓度处理组(50 mg/kg)、姜黄素中浓度处理组(100 mg/kg)、姜黄素高浓度处理组(200 mg/kg)，每组10只。常温及干热对照组给予0.9%生理盐水灌胃，姜黄素组大鼠给予不同浓度姜黄素溶液灌胃，连续7 d。第8天除常温对照组外，其余4组大鼠均转移到模拟干热环境实验舱中。入舱实验的第150 min达到热射病状态，麻醉处死大鼠后留取尿液、肾组织进行分析，肾损伤分子-1(KIM-1)试剂盒检测尿液KIM-1水平变化，苏木精-伊红(HE)染色观察各组大鼠肾组织病理形态变化，进行肾损伤病理学评分，细胞凋亡缺口末端标记技术(TUNEL)检测细胞凋亡并计算凋亡率。 结果常温对照组尿液KIM-1水平、肾损伤病理学评分、肾组织细胞凋亡率分别为[(100.36±5.54)ng/L]、[(35.50±9.52)分]、[(0.55±0.04)%]；干热对照组大鼠各指标分别为[(1 060.57±75.50)ng/L]、[(710.67±74.60)分]、[(5.53±0.48)%]；姜黄素低浓度处理组各指标分别为[(945.73±48.07)ng/L]、[(701.67±64.84)分]、[(5.10±0.37)%]；姜黄素中浓度处理组各指标分别为[(639.17±44.71)ng/L]、[(365.00±34.06)分]、[(2.05±0.35)%]；姜黄素高浓度处理组各指标分别为[(592.67±34.29)ng/L]、[(289.00±35.08)分]、[(1.33±0.20)%]。各项指标水平在各组间比较，均差异有统计学意义(F＝373.70，203.16，289.81；均P<0.01)，干热对照组KIM-1水平和肾损伤病理学评分均明显高于常温对照组(t＝31.04，21.99；均P<0.01)。肾损伤病理学评分和肾组织细胞凋亡率在姜黄素低浓度组和干热对照组之间比较，均差异无统计学意义(t＝0.22，1.74；均P>0.05)，姜黄素中浓度处理组(t＝10.33，14.43)、高浓度处理组(t＝12.53，19.82)与干热对照组之间比较，均差异有统计学意义(均P<0.01)。 结论姜黄素预处理对干热环境热射病大鼠肾损伤具有一定的保护作用，可能通过阻断肾细胞凋亡通路发挥对肾脏损伤的保护作用。     

Cross-presentation of glycoprotein 96-associated antigens on major histocompatibility complex class I molecules requires receptor-mediated endocytosis

Heat shock proteins (HSPs) like glycoprotein (gp)96 (glucose-regulated protein 94 [grp94]) are able to induce specific cytotoxic T lymphocyte (CTL) responses against cells from which they originate. Here, we demonstrate that for CTL activation by gp96-chaperoned peptides, specific receptor-mediated uptake of gp96 by antigen-presenting cells (APCs) is required. Moreover, we show that in both humans and mice, only professional APCs like dendritic cells (DCs), macrophages, and B cells, but not T cells, are able to bind gp96. The binding is saturable and can be inhibited using unlabeled gp96 molecules. Receptor binding by APCs leads to a rapid internalization of gp96, which colocalizes with endocytosed major histocompatibility complex (MHC) class I and class II molecules in endosomal compartments. Incubation of gp96 molecules isolated from cells expressing an adenovirus type 5 E1B epitope with the DC line D1 results in the activation of E1B-specific CTLs. This CTL activation can be specifically inhibited by the addition of irrelevant gp96 molecules not associated with E1B peptides. Our results demonstrate that only receptor-mediated endocytosis of gp96 molecules leads to MHC class I-restricted re-presentation of gp96-associated peptides and CTL activation; non-receptor-mediated, nonspecific endocytosis is not able to do so. Thus, we provide evidence on the mechanisms by which gp96 is participating in the cross-presentation of antigens from cellular origin.     

热休克蛋白70大鼠脑弥漫性轴索损伤后神经元保护及修复作用研究

目的探讨大鼠脑弥漫性轴索损伤(diffuseaxonalinjuries,DAI)后不同时期脑皮层组织中热休克蛋白(heatshockproteins,HSP)70的表达,为临床治疗脑损伤寻求有效手段。方法制作大鼠DAI模型,分别在伤后6、24、48、72h,7d以免疫组织化学方法检测大鼠脑皮层成纤维细胞生长因子(bFGF)的表达,分析其含量变化特点。结果DAI后24hHSP表达增加,48h达高峰,7d后仍维持较高水平。结论bFGF在各时间点表达有明显差异,提示其参与脑损伤后神经元保护及修复过程。     

白介素6基因启动子区多态性与体重指数和炎症因子等生化指标的相关性及与冠心病发生发展关系的探索

本研究旨在通过对中国北方地区汉族人IL-6基因启动子区-572G／C，-597G／A多态性与体重指数（BMI）和炎症因子等生化指标的相关性的调查，探索基因多态性与冠心病（CHD）发生发展的关系。采用荧光杂交探针、以荧光共振能量转移原理和熔点曲线分析技术，测定了194例冠心病患者和123例健康对照者的IL-6基因型，同时测定BMI、超敏C反应蛋白（hsCRP）、血脂、载脂蛋白等指标，并通过建立逻辑回归（Logistic regression）模型分析CHD发生的危险因素。结果表明，在所有观察对象中发现中国北方汉族人IL-6基因启动子区-597位点有7例为GA型．其余均为GG型，尚未发现AA型，未发现其多态性与BMI和炎症因子等生化指标的相关性。冠心病（cor—onary heart disease，CHD）组与对照组-572G／C基因型频率和等位基因频率分布差异无统计学意义，但是CHD组和对照组携带G等位基因和非G等位基因频率相比差异有统计学意义（P=0，0425）。正常对照组中携带G等位基因者收缩压中位数水平明显高于非G等位基因者（P=0、02）。在所有研究对象中，与非G等位基因组相比，携带G等位基因组的体重指数、超敏C反应蛋白、收缩压中位数水平显著升高（P值分别为0、026、0．022、0、005）。经Logistic逐步回归分析显示，年龄、血清甘油三脂、性别、高血压、载脂蛋白C2、血清总胆固醇、脂蛋白a是冠心病发生的危险因子，而载脂蛋白A1是保护因子（P〈0．05），未见-572G／C的G等位基因是一独立的危险因素。结论：IL-6基因启动子区-597G／A多态性和CHD的易感性无关，而-572G／C多态性与CHD的易感性有关，其机制可能与-572G／C多态性可导致BMI、hsCRP和血压的变化有关。     

Immunopathogenesis and biomarkers of recurrent atrial fibrillation following ablation therapy in patients with preexisting atrial fibrillation

Introduction: Recurrent atrial fibrillation (RAF) following ablation therapy occurs in about 50% of patients. The pathogenesis of RAF is unknown, but is believed to be driven by atrial remodeling in the setting of background inflammation. Structural, electrophysiological and mechanical remodeling has been associated with atrial fibrillation (AF). Inflammation and fibrotic remodeling are the major factors perpetuating AF, as mediators released from the atrial tissues and cardiomyocytes due to mechanical and surgical injury could initiate the inflammatory process. In this article, we have critically reviewed the key mediators that may serve as potential biomarkers to predict RAF.

Areas covered: Damage associated molecular patterns, heat shock proteins, inflammatory cytokines, non-inflammatory markers, markers of inflammatory cell activity, and markers of collagen deposition and metabolism are evaluated as potential biomarkers with molecular treatment options in RAF.

Expert commentary: Establishing biomarkers to predict RAF could be useful in reducing morbidity and mortality. Investigations into the role of DAMPs participating in a sterile immune response may provide greater insight into the pathogenesis of RAF. Markers evaluating immune cell activity, collagen deposition, and levels of heat shock proteins show the greatest promise as potential biomarkers to predict RAF and develop novel therapies.     

热应激复合敌敌畏中毒对小鼠全血乙酰胆碱脂酶和组织抗氧化能力的影响

目的研究热应激复合有机磷敌敌畏（O,O-dimethyl-O-2,2-dichlorovinylphosphate,DDVP）中毒对小鼠全血乙酰胆碱酯酶活性及组织脂质过氧化的影响。方法将54只小鼠随机分为对照组、热应激组和热应激复合DDVP中毒组。实验舱相对湿度控制在（60±5）%,对照组小鼠置于24℃环境下1 h,热应激组小鼠置于38或40℃的热环境下1 h。有机磷中毒组小鼠经腹腔注射给予9或15 mg/kg DDVP,对照组给予等量生理盐水。30 min后,取全血测量乙酰胆碱酯酶（AChE）活性,取心、脑和肝组织匀浆,测量其超氧化物歧化酶（SOD）活性、丙二醛（MDA）含量和羟自由基（.OH）抑制能力。实验期间观察小鼠一般情况,记录实验前后小鼠体质量。结果热环境（38或40℃）暴露使小鼠烦躁不安,活动量明显增加,摄水量降低,体质量减轻。与不同环境温度暴露的对照组相比,热应激复合DDVP中毒组小鼠全血AChE活性和心、脑和肝组织SOD活性和羟自由基抑制能力均明显下降（P〈0.05）,而MDA含量明显升高（P〈0.05）。热应激和DDVP中毒对上述指标的影响有交互作用。结论在本实验条件下,热应激和DDVP中毒对小鼠乙酰胆碱酯酶有显著的抑制作用,同时可引起组织脂质过氧化增强,提示氧化应激机制与高热复合DDVP中毒的加重效应有关。