缺血后适应对兔短期缺血再灌注心肌细胞凋亡的影响

目的探讨缺血后适应对兔局部短期缺血再灌注心肌细胞凋亡及Bcl-2、Bax蛋白表达的影响。方法18只新西兰白兔随机分成3组，每组6只；假手术对照组（S组）、缺血，再灌注对照组（IR组）、缺血后适应组（Post组）。除S组外，其余两组均接受左冠脉前降支15min阻断和30min再灌注，Post组在15min缺血后接受连续3次每次再灌注30s，缺血30s的后适应。以DNA电泳和TUNEL分析检测兔短期缺血再灌注心肌组织的细胞凋亡情况，免疫组织化学方法检测Bcl-2、Bax蛋白的表达。结果兔IR组缺血区心肌DNA电泳呈现DNA梯形，而Post组和s组未见梯形。Post组心肌细胞凋亡指数显著低于IR组[（28．06±2．92）％，（55．70±13．96）％，P〈0．01]。Bcl-2基因的蛋白表达量Post组高于IR组（10．00±0．89，7．83±1．47，P〈0．05）；Bax基因的蛋白表达量Post组低于IR组（7．50±0．84，9．83±0．98，P〈0．05）。结论缺血后适应显著减少了兔短期缺血再灌注诱导的心肌细胞凋亡程度与上调Bcl-2基因的蛋白表达，下调Bax基因的蛋白表达有关。     

缺血预处理与急性心肌缺血/再灌注细胞凋亡及Bcl-2、BaX蛋白表达的关系

目的：研究缺血预处理对急性心肌缺血／再灌注细胞凋亡的影响及与Bcl-2,Bax蛋白表达的关系。方法：用在体心肌缺血／再灌注模型，将实验动物分为3组：对照组，缺血／再灌注组，缺血预处理组。分别用原末端标记（TUNEL）法测定凋亡细胞和用免疫组化法测定Bcl-2,Bax蛋白的表达。结果：与对照组相比，缺血／再灌注组增加凋亡心肌细胞的百分数（P＜0．01）及Bax蛋白的光密度值（P＜0．01），减小Bcl-2蛋白的光密度值（P＜0．01），与缺血／再灌注组相比，缺血预处理减小凋亡心肌细胞百分数（P＜0．01）及Bax蛋白的光密度值（P＜0．05），增加Bcl-2蛋白的光密度值（P＜0．01）。结论：缺血预处理通过调控Bcl-2/Bax表达而抑制心肌缺血／再灌注细胞凋亡。     

肝糖原贮备对热缺血再灌注大鼠肝细胞凋亡的影响

目的探讨肝糖原贮备对热缺血再灌注肝细胞凋亡及肝损伤的影响。方法建立大鼠肝热缺血模型。实验分组：术前24h静脉注射25％葡萄糖组，2ml／只，每6h1次，高糖饮食（H组）；术前禁食24h，饮水不限（L组）；正常饮食对照组（N组）和假手术组（S组）。缺血45min，再灌注2、24h取材。流式细胞术检测细胞凋亡及Bcl-2、Bax蛋白。同时进行肝酶学检测、肝组织形态学观察。结果1．细胞凋亡及蛋白表达：（1）24h细胞凋亡百分率。s组〈H组〈N组〈L组（P〈0．01），各组24h凋亡率均高于2h（P〈0．01，S组除外）。（2）Bcl-2、Bax蛋白表达量。①再灌注24hBcl-2表达量：H组明显高于其余3组（P〈0．01），L组〈N组（P〈0．05），与2h比较H组表达升高（P〈0．01）；②再灌注24hBax表达量：S组明显低于其余3组（P〈0．01），L组〉N组（P〈0．01）。2．肝酶学指标：各时相点4组间比较差异有统计学意义（P〈0．05），S组〈H组〈N组〈L组。3．肝脏病理组织学改变：再灌注24hH组明显轻于N组及L组，并接近S组，L组最严重。结论预防性增加肝糖原贮备可抑制热缺血再灌注过程中肝细胞凋亡，减轻肝损伤，并可能通过影响Bcl-2、Bax的表达发挥作用。     

大鼠小肠缺血再灌注后血中NO和SOD浓度与肺损伤的相关性研究

目的：探讨大鼠小肠缺血再灌注后血中-氧化氮（NO），超氧化物歧化酶（superoxidediamu—tase，SOD）的浓度变化与肺组织中Bax、Bcl-2、p53的表达及肺组织超微结构变化的相关性。方法：建立小肠缺血再灌注模型，分为对照组，再灌注后0、30min，1、2h，1、3、7d共8组，于各时相点检测血中NO和SOD的浓度，用免疫组织化学SP法观察肺组织中Bax、Bcl-2、p53的表达情况，透射电子显微镜观察肺组织细胞超微结构变化。结果：大鼠小肠缺血再灌注后0rainNO浓度升高，但至再灌注2h时则明显阳氏，其后又持续升高，至再灌注7d时达高峰。SOD浓度在再灌注0min明显下降，再灌注2h时升高，随后持续下降，至再灌注7d时达最低水平。Bax、Bcl-2免疫阳性细胞主要位于肺组织中血管内皮细胞和肺泡上皮细胞。再灌注0min，Bax、Bcl-2阳性细胞表达率升高，30min时其阳性细胞表达率均分别升高为17．1％和78．1％，Bcl-2表达高于Bax（P〈0．01）。2h时降低，其后升高，7d时阳性细胞表达率达到高峰，分别为94．1％和83．4％，Bax表达明显高于Bcl-2（P〈0．01）。透射电子显微镜显示肺组织细胞超微结构损伤改变。结论：血中NO、SOD浓度变化和肺组织中超微结构的改变说明小肠缺血再灌注后可引起肺组织细胞凋亡和损伤，而大鼠小肠缺血再灌注后Bax、Bcl-2、p53在肺组织细胞中的阳性表达均有明显改变并可能引起细胞凋亡和损伤。     

Bcl-2/Bax及Caspase-3在心肌缺血再灌注引起的急性肺损伤中的表达及作用

目的 探讨Bcl-2/Bax及Caspase-3在心肌缺血再灌注及后处理对大鼠肺损伤的表达及作用.方法 雄性SD大鼠30只随机分为3组,每组10只,假手术组（S）、心肌缺血/再灌注组（IR）、缺血后处理组（IPost）.结扎左冠状动脉前降支制备心肌缺血/再灌注模型,后处理组于再灌注前1 min内,连续3个循环灌注10s,缺血10s,再灌注120 min后快速取肺.SP法测定肺组织内Bcl-2/Bax及Caspase-3.TUNEL法检测细胞凋亡.结果 与S组相比较,IR组,IPost组,Bax,Caspase-3,Bcl-2表达减少（P＜0.01）,细胞凋亡增多;与IR组相比较,IPost组,Bax,Caspase-3,细胞凋亡（TUNEL）表达减少,Bcl-2表达增多（P＜0.01）,细胞凋亡减少.结论 缺血后处理可以诱导Bcl-2表达增强,Bax及Caspase-3表达降低,从而减轻肺损伤.     

异丙酚对肝移植大鼠肝窦内皮细胞凋亡的影响

目的研究异丙酚对肝移植大鼠肝窦内皮细胞（SEC）凋亡的影响。方法24只健康雄性SD大鼠建立大鼠原位肝移植模型,随机分为3组（n=8）。Ⅰ组（对照组）移植肝再灌注前30min腹腔注射生理盐水15ml/kg；Ⅱ组和Ⅲ组移植肝再灌注前30min分别腹腔注射异丙酚100mg/kg和50mg/ kg。移植肝再灌注6h后取下腔静脉血,测定血浆谷丙转氨酶（ALT）、谷草转氨酶（AST）活性,TUNEL法测定移植肝SEC凋亡,Western blot法测定肝组织Bcl-2及Bax蛋白表达。结果再灌注6h后,与Ⅰ组比较,Ⅱ组、Ⅲ组大鼠血浆ALT、AST活性降低,凋亡SEC减少,Bcl-2蛋白表达上调,Bax蛋白表达下调（P＜0．01）；与Ⅱ组比较,Ⅲ组大鼠血浆ALT、AST活性增高,凋亡SEC增多,Bax蛋白表达上调（P＜0．01）,Bcl-2蛋白表达下调（P＜0．05）。结论异丙酚可剂量依赖性地抑制大鼠移植肝早期再灌注肝窦内皮细胞凋亡,其机制与上调Bcl-2蛋白表达、下调Bax蛋白表达有关。     

缺血预处理对大鼠皮瓣缺血再灌注后Bcl-2和Bax基因表达的影响

目的探讨缺血预处理（IPC）对大鼠皮瓣缺血再灌注（I／R）后凋亡相关蛋白表达的影响及其对皮瓣缺血再灌注损伤保护作用机制。方法采用Wistar大鼠为实验动物，制备右下腹岛状皮瓣I／R模型。90只大鼠随机分为对照组、I／R组和IPC组。采用SABC法观察IPC对大鼠皮瓣缺血再灌注后Bcl-2、Bax蛋白表达规律。结果SABC法观察显示Bcl-2在缺血再灌注后4h有少量表达，24h达峰值，7d时明显减少。IPC组再灌注后4h表达较弱，3d达峰值，7d时明显减弱。IPC组与I／R组比较，Bcl-2在I／R后3d差异有统计学意义（P〈0．01）。Bax基因在I／R后4h表达，3d时达峰值，7d时仍有较高水平表达；IPC组各时间点Bax基因呈低表达，与I／R组比较，3d和7d时差异最显著（P〈0．01）。结论IPC诱导Bcl-2基因表达增加和抑制Bax基因表达可能是IPC诱导抗凋亡、产生皮瓣保护机制的原因之一。     

逆行灌注心脏不停跳双瓣膜置换术围术期心肌细胞凋亡及Bcl-2,Bax的表达

目的观察逆行灌注心脏不停跳双瓣膜置换术围术期心肌细胞凋亡及Bcl-2，Bax蛋白表达的变化。方法将26例风湿性心脏病患者分为两组，实验组：14例，阻断主动脉后浅低温逆行灌注持续给予氧合血，使心脏缓慢跳动（40～50次／分）；对照组：12例，中度低温阻断主动脉后根部灌注高钾含血停搏液，待心脏停搏后改为逆行灌注。术中多时点检测血浆肌酸激酶同工酶（CK-MB）、心肌肌钙蛋白T（cTnT）的含量；分别于体外循环（CPB）前，CPB后30min留取右心房标本，检测心肌凋亡细胞及免疫组化法测定心肌细胞Bcl-2和Bax蛋白表达。结果与CPB前比较，主动脉阻断30min时两组CK-MB、cTnT和心肌细胞凋亡数明显升高（P〈0．01），Bax表达明显降低（P〈0．01），实验组Bcl-2表达降低不明显（P〉0．05），而对照组Bcl-2表达降低明显（P〈0．01）。与对照组比较，主动脉阻断30min后实验组CK-MB、cTnT和心肌细胞凋亡数明显降低（P〈0．05），Bcl-2表达明显升高（P〈0．01）。结论逆行灌注心脏不停跳双瓣膜置换术与心脏停搏手术相比较，对心肌细胞凋亡的影响较小，可能与维持Bcl-2蛋白表达水平，抑制Bcl-2／Bax基因向Bax偏移等因素有关。     

七氟醚后处理对大鼠心肌缺血再灌注时细胞凋亡的影响

目的 评价七氟醚后处理对大鼠心肌缺血再灌注时心肌细胞凋亡的影响.方法 健康雄性Wistar大鼠45只,体重250～ 280 g,采用随机数字表法,将大鼠随机分为3组(n=15):假手术组(S组)、心肌缺血再灌注组(I/R组)和七氟醚后处理组(Spo组).I/R组和Spo组采用结扎左冠状动脉前降支30 min时进行再灌注120 min的方法制备心肌缺血再灌注损伤模型,S组仅在左冠状动脉前降支下穿线.Spo组进行七氟醚后处理,于再灌注前1 min时吸八七氟醚,呼气末浓度2.5％,持续5min.于再灌注120 min时取左室心肌组织,测定缺血危险区和梗死区体积,计算缺血危险区和梗死区体积百分比.取左室缺血危险区心肌组织,测定心肌细胞凋亡指数,测定凋亡相关蛋白Bcl-2和Bax的蛋白及其mRNA的表达,计算Bcl-2/Bax比值.结果 与S组比较,I/R组心肌梗死区体积百分比和心肌细胞凋亡指数升高,Bcl-2、Bax蛋白及mRNA表达上调,Bcl-2/Bax比值降低(P＜0.05);与I/R组比较,Spo组心肌梗死区体积百分比和心肌细胞凋亡指数降低,Bax蛋白及mRNA表达下调,Bcl-2蛋白及mRNA表达上调,Bcl-2/Bax比值升高(P＜0.05).结论 七氟醚后处理通过上调Bcl-2表达,下调BBax表达,改善Bcl-2/Bax平衡,抑制心肌细胞凋亡,从而减轻大鼠心肌缺血再灌注损伤.     

丙泊酚对2型糖尿病大鼠心肌缺血-再灌注损伤时凋亡蛋白Bax和Bcl-2的影响

目的观察丙泊酚对2型糖尿病大鼠心肌缺血-再灌注损伤时凋亡蛋白Bax和Bcl-2表达的影响。方法雄性Wistar大鼠48只,随机均分为心肌缺血-再灌注组(CI组)、心肌缺血-再灌注+丙泊酚组(CP组)、假手术组(CC组),以及糖尿病心肌缺血-再灌注组(DI组)、糖尿病心肌缺血-再灌注+丙泊酚组(DP组)、糖尿病假手术组(DC组)。采用高脂高糖饮食复合腹腔注射链脲佐菌素(STZ)方法制备2型糖尿病模型。DI组和CI组采用结扎左冠状动脉前降支30min再灌注2h的方法制备心肌缺血-再灌注模型。DP组、CP组在缺血前10min开始静脉泵注丙泊酚6mg·kg-1·h-1至再灌注2h结束,DI组、CI组给予等容量的生理盐水;DC组、CC组仅穿线不结扎。再灌注结束后,取病变部分心肌,光镜下观察缺血心肌形态学改变,免疫组化法测定心肌Bax和Bcl-2表达水平,并计算Bcl-2和Bax表达的比值。结果与CC组比较,CI组和CP组Bcl-2、Bax表达明显上调,CI组Bcl-2/Bax明显下降(P0.05)。与CI组比较,CP组Bax表达明显下调,Bcl-2表达明显上调,Bcl-2/Bax明显升高(P0.05),DI组Bcl-2、Bax表达明显上调(P0.05)。与DC组比较,DI组和DP组Bcl-2、Bax表达明显上调,DI组Bcl-2/Bax明显下降(P0.05)。与DI组比较,DP组Bax表达明显下调,Bcl-2表达明显上调,Bcl-2/Bax明显升高(P0.05)。结论丙泊酚可上调抗凋亡蛋白Bcl-2表达、下调凋亡前蛋白Bax的表达,并减轻正常大鼠和2型糖尿病大鼠心肌缺血-再灌注损伤。     

Hypotension, hypoxia, and head injury: frequency, duration, and consequences

BACKGROUND: Retrospective studies have suggested an association between systemic hypotension and hypoxia and worsened outcome from traumatic brain injury. Little is known, however, about the frequency and duration of these potentially preventable causes of secondary brain injury. HYPOTHESIS: Early episodes of hypoxia and hypotension occurring during initial resuscitation will have a significant impact on outcome following traumatic brain injury. DESIGN: Prospective cohort study. SETTING: Urban level I trauma center. PATIENTS: Patients with a traumatic brain injury who had a Glasgow Coma Score of 12 or less within the first 24 hours of admission to the hospital and computed tomographic scan results demonstrating intracranial pathologic features. Patients who died in the emergency department were excluded from the study. MAIN OUTCOME MEASURES: Automated blood pressure and pulse oximetry readings were collected prospectively from the time of arrival through initial resuscitation. The number and duration of hypotensive (systolic blood pressure, < or =90 mm Hg) and hypoxic (oxygen saturation, < or =92%) events were analyzed for their association with mortality and neurological outcome. RESULTS: One hundred seven patients met the enrollment criteria (median Glasgow Coma Score, 7). Overall mortality was 43%. Twenty-six patients (24%) had hypotension while in the emergency department, with an average of 1.5 episodes per patient (mean duration, 9.1 minutes). Of these 26 patients with hypotension, 17 (65%) died (P =.01). When the number of hypotensive episodes increased from 1 to 2 or more, the odds ratio for death increased from 2.1 to 8.1. Forty-one patients (38%) had hypoxia, with an average of 2.1 episodes per patient (mean duration, 8.7 minutes). Of these 41 patients with hypoxia, 18 (44%) died (P =.68). CONCLUSIONS: Hypotension, but not hypoxia, occurring in the initial phase of resuscitation is significantly (P =.009) associated with increased mortality following brain injury, even when episodes are relatively short. These prospective data reinforce the need for early continuous monitoring and improved treatment of hypotension in brain-injured patients.     

Data,information, knowledge,wisdom, and understanding

The digital age commenced in the mid-20th century and since we have seen approximately exponential growth in information. This period has also seen the rapid growth of computer technology that has facilitated, for instance, the derivation of whole genomes and automated drug discovery. Data, information, knowledge and wisdom lay the foundations for understanding how experience is formed from evidence and observations. When data are put into context, the resultant information can drive growth and further contribute to increased knowledge. Appreciating the source of data enables us to recognize and hopefully correct for inherent error and bias. Ultimately knowledge discovery can be automated to gain information from data and so on, enhancing our understanding of a given subject and expanding collective wisdom.     

Distribution, elimination, and action of d-tubocurarine in neonates, infants, children, and adults

The relation of plasma concentration of d-tubocurarine (dTc) to neuromuscular blockade, and the distribution and urinary excretion of dTc was determined in neonates (n = 4), infants (n = 6), children (n = 8), and adults (n = 8). The plasma concentration-time course curves to 24 hr are best described for all groups by three-compartment models. Both neonates and infants exhibit decreased plasma clearance (CLP), 1.1 +/- 0.08 and 1.0 +/- 0.06 ml X kg-1 X min-1, and in addition a prolonged t1/2 terminal phase, 311 +/- 44 and 306 +/- 35 (mean +/- SEM, min). The neonates' 24-hr urinary excretion, 27 +/- 2 (mean +/- SEM, % total dose) is significantly less than the adult value, 45 +/- 4% total dose. There was no significant difference seen in the log plasma concentration-evoked compound electromyogram (ECEMG) response between 20-80% paralysis for adults, children, infants, and five of the seven neonates studied. Two of the neonates had a significant shift of their log concentration-response curve to the right. There was also no significant difference between any of the groups in the time for 50% return of ECEMG stimulus height or the time required for recovery of the ECEMG from 25 to 75% of control value. for recovery of the ECEMG from 25 to 75% of control value.     

Laparotomy, laparoscopy, cancer, and beyond

The fate of laparoscopic methods for the treatment of cancer remains uncertain. Published middle-range oncologic results from nonrandomized studies demonstrate that laparoscopic methods are associated with an outcome comparable with results after open resection. The world awaits the 3- and 5-year oncologic results of the ongoing randomized and prospective trials. There is a possibility that laparoscopic methods may be associated with a survival benefit. Port tumors remain a concern. However, results at this writing suggest that these recurrences take place at a frequency similar to that of incisional recurrences following open cancer resection. Port tumors currently are viewed as local recurrences. Traumatization of the tumor at the time of resection is thought to be the most important surgery-related risk factor. The demonstration of a survival benefit in a randomized trial would likely have a tremendous impact on the surgical world. Avoidance of laparotomy-related immunosuppression and tumor stimulation, both of which have been well demonstrated in animal studies, theoretically, might account for differences in cancer outcome. The early postoperative period may be a critical time during which the fate of many cancer patients is determined. It is possible that this may be an ideal time frame for antitumor immunotherapy because the tumor burden is at its lowest, and because immunotherapy, unlike conventional chemotherapy, is unlikely to have a negative impact on wound and anastomotic healing. Perioperative nonspecific upregulation of immune function via pharmacologic means may improve long-term oncologic results. Similarly, preoperative tumor vaccines might provide patients with a specific means of combating any remaining tumor cells after curative resection. The results of several recently completed murine studies support both of these ideas. Finally, early postoperative administration of monoclonal antitumor antibodies might provide patients with specific means of combating any remaining tumor cells after curative resection. The introduction of advanced minimally invasive techniques nearly a decade ago has led to new methods of approaching malignant tumors that have the potential to have an impact on the oncologic outcome of cancer patients. This decade-long journey also has led to new insights regarding the impact of surgery on the patient. It also has alerted us concerning the importance of the immediate postoperative period in the patient's ongoing struggle against the tumor. These insights hopefully will lead to better surgical methods and new perioperative adjuvant therapies that will increase the rate of survival and reduce the recurrence rates for cancer patients.