胸腰椎骨折手术患者术后肺部感染率情况及多因素Logistic回归分析

目的探讨胸腰段骨折手术患者术后肺部感染情况,并进行相关因素的多因素Logistic回归分析。方法纳入2011年12月~2017年12月于本院治疗的584例胸腰椎骨折患者,均采用后路手术治疗,记录术后发生肺部感染人数,设为感染组,其余设为非感染组。调查两组性别、年龄、骨折情况等病历资料,经单因素及多因素Logistic回归分析探讨患者术后肺部感染的独立危险因素。结果 584例患者术后发生肺部感染40例,感染率6.85%。单因素分析显示,两组住院时间、吸烟史、合并慢性肺部疾病、卧床时间、麻醉方式、出血量、合并糖尿病、手术节段、手术时间、手术路径、合并脊髓神经损伤等差异均有统计学意义(P0.05);多因素Logistic回归分析显示,住院时间14 d(OR=3.133)、卧床时间7 d(OR=2.856)、合并慢性肺部疾病(OR=2.456)、吸烟史(OR=2.012)、全身麻醉(OR=2.656)是患者术后肺部感染率的独立危险因素。结论胸腰椎骨折手术患者术后肺部感染与住院时间14 d、卧床时间7 d、合并慢性肺部疾病、吸烟史、全身麻醉等多种因素有关,临床应制定相应措施以降低肺部感染率。     

腰椎滑脱症术后伤口感染危险因素分析

目的：探讨腰椎滑脱症术后伤口感染发生的相关危险因素。方法：对2013年1月至2017年12月因腰椎滑脱症行后路减压融合内固定术的296例患者进行回顾性分析,根据术后伤口是否感染分为感染组29例,男13例,女16例,平均年龄（67.03±1.01）岁;非感染组267例,男91例,女176例,平均年龄（52.32±16.08）岁。记录两组患者的性别、年龄、肥胖体重指数（BMI）、吸烟史、糖尿病史、激素药物使用史、白蛋白水平、手术时间、美国麻醉医师协会评分（ASA评分）、围手术期输血、引流管时间等,对单因素Logistic回归分析有统计学意义的危险因素进行多元Logistic回归分析,同时采用SPSS决策树模型确定连续性变量的分层界点,进一步明确独立危险因素。结果：296例患者中术后共有29例发生手术切口感染,发生率约9.8%（29/296）。感染组与非感染组在BMI、年龄、糖尿病史、引流管时间、激素药物使用史、白蛋白水平、手术时间差异有统计学意义（P<0.05）;单因素Logistic回归分析排除各因素间的相互影响后结果显示：肥胖、年龄、糖尿病史、激素药物使用史、手术时间、引流管时间可能为腰椎滑脱症术后伤口感染的危险因素,将上述可能的危险因素纳入多因素Logistic回归分析显示：年龄、糖尿病史、激素药物使用史、引流管时间是术后伤口感染的独立危险因素。结论：年龄、糖尿病史、激素药物使用史、引流管时间是术后伤口感染的独立危险因素,年龄≥64岁、引流管留置时间超过48 h、合并糖尿病、激素药物使用是术后发生伤口感染的高危因素。     

肝癌肝切除术后感染性并发症的危险因素分析

目的：探讨肝癌行肝切除术患者术后并发感染的高危因素。
　　方法：回顾性分析2009年1月—2014年6月收治的157例行肝切除术治疗的肝癌患者的临床资料,根据肝切除术后是否合并感染,分为感染组（n=27）和非感染组（n=130）,对可能与并发感染相关的因素进行分析,了解其与肝切除术后并发感染的相关性。
　　结果：糖尿病病史、术前血清白蛋白低、术中失血量、术中输血量和腹腔引流管放置时间这5个因素是肝癌肝切除术后感染的相关危险因素。多因素Logistic回归分析显示,糖尿病病史、术前血清白蛋白低、术中输血量≥800mL和腹腔引流管放置时间>7d是肝癌肝切除术后感染的独立危险因素。
　　结论：糖尿病病史、术前白蛋白水平低、术中输血量≥4个单位以及腹腔引流管放置为肝癌肝切除术后患者感染的独立危险因素。对于存在以上情况的患者,术后应加强预防感染治疗,避免术后感染的发生。     

腹腔镜下胆囊切除术后并发肠粘连的危险因素分析

目的探讨腹腔镜下胆囊切除术(LC)后并发肠粘连(IA)的危险因素及预防措施。方法 2015年4月～2018年4月行LC治疗者224例,根据是否发生术后肠粘连,将其分为术后发生肠粘连组(45例)与未发生肠粘连组(179例),对两组肛门排气时间、性别、腹腔残余感染、体质指数(BMI)、施术者LC术操作经验、年龄、合并症、留置引流管等指标进行单因素分析,对单因素分析有意义的指标进行Logistic回归分析。结果 LC术后发生肠粘连45例,未发生肠粘连179例;肠粘连病人随机分为保守治疗组25例,腹腔镜下肠粘连松解术治疗组20例。LC术后发生肠粘连组留置腹腔引流管、术后腹腔残余感染、合并糖尿病、术后肛门排气时间24小时、施术者LC术操作≤50例所占比例明显高于术后未发生肠粘连组,差异有统计学意义(P0.05)。合并糖尿病、术后腹腔残余感染、术后留置引流管、施术者LC术操作≤50例为LC术后影响肠粘连发生的独立危险因素(P0.05)。结论合并糖尿病、术后腹腔残余感染、术后留置引流管、施术者LC术操作≤50例为腹腔镜下胆囊切除病人术后并发肠粘连的危险因素。     

胆道手术后发生腹腔复杂感染的临床特点分析

目的 分析胆道手术后发生腹腔复杂感染的临床特点。方法 选取医院2019年1月至2023年1月收治的1580例行胆道手术患者临床资料进行回顾性分析。统计患者发生腹腔复杂感染情况,分析病原菌分布,对引发感染的相关因素进行分析。结果 1580例患者中42例发生腹腔复杂感染,感染率为2.66%;感染患者经细菌培养后共计检出病原菌56株,革兰氏阴性菌43株,占比76.8%,革兰氏阳性菌12株,占比21.4%,真菌1株,占比1.8%。经单因素分析结果显示,年龄、手术时间、合并糖尿病、既往胆道手术史及引流管留置时间是腹腔复杂感染的相关影响因素（P<0.05）;多因素Logistic回归分析显示,年龄大、手术时间长、合并糖尿病、既往胆道手术史及引流管留置时间长是腹腔复杂感染的相关危险因素（P<0.05）。结论 胆道手术患者术后发生腹腔复杂感染的概率较高,引发感染的危险因素多,高龄、手术时间长、合并糖尿病、既往胆道手术史及引流管留置时间长的患者术后发生感染的风险更高,临床应针对影响因素进行防治措施制定,应用合理综合治疗,以降低感染。     

食管癌术后并发肺部感染的相关因素

目的探讨食管癌患者术后并发肺部感染的相关因素,为临床预防术后肺部感染的发生、提高手术效果提供参考依据。 方法回顾性分析2012至2013年川北医学院附属医院胸外科接受食管癌根治术的215例患者的临床资料,按照术后是否发生肺部感染,将其分为感染组和对照组,其中感染组患者95例,男性73例,女性22例,平均年龄（63.8±7.5）岁;对照组患者120例,男性83例,女性37例,平均年龄（61.7±6.3）岁。利用卡方检验对两组病例的性别、年龄、病变部位、吸烟史、手术持续时间、术后呼吸机辅助呼吸时间及术前并发症进行率的比较,并通过Logistic多因素回归分析方法进一步明确食管癌切除术后并发肺部感染的危险因素。 结果卡方检验结果表明,术后肺感染组患者高龄（≥ 60岁）、肿瘤发生部位、吸烟史（≥ 20年）、手术持续时间（≥ 3 h）、术后呼吸机辅助呼吸时间（≥ 2 h）、术前并发症（糖尿病、COPD Ⅲ级以上、低蛋白血症）的比重均高于对照组（P均<0.05）。Logistic多因素回归分析表明,年龄≥ 60岁（χ² = 4.201、P = 0.04）、烟龄≥ 20年（χ² = 11.204、P = 0.001）、病变部位（χ² = 12.415、P = 0.000）、手术时间≥ 3 h（χ² =4.28、P = 0.045）、术后呼吸机辅助呼吸时间≥ 2 h（χ² = 4.565、P = 0.033）、术前并发糖尿病（χ² = 7.335,P = 0.007）、术前合并低蛋白血症（χ² = 4.97、P = 0.026）及术前合并COPD Ⅲ级以上（χ² = 5.225、P = 0.022）是食管癌术后并发肺部感染的高危因素。 结论年龄≥ 60岁、烟龄≥ 20年、肿瘤发生部位、手术时间≥ 3 h、术后呼吸机辅助呼吸时间≥ 2 h、术前合并糖尿病、低蛋白血症或重度肺功能受损是食管癌切除术后并发肺部感染的高危因素。     

成人医疗保健相关性复杂性腹腔感染的危险因素分析

背景与目的:复杂性腹腔感染(cIAI)是外科术后并发的第二大最常见的感染,虽然目前诊疗水平在不断提高,但是cIAI的病死率仍高,住院期间并发cIAI,不仅危及患者的生命,并且对患者的长期预后产生不利影响。本研究探讨医疗保健相关性cIAI(HA-cIAI)的危险因素,为临床诊疗活动中采取适当的干预措施提供依据,以期降低HA-cIAI的发生率。方法:回顾性分析2011年11月—2016年7月在中南大学湘雅医院住院期间留取腹腔积液标本行快速细菌需氧培养阳性并临床诊断为cIAI的359例成人患者的临床资料,其中社区获得性cIAI患者143例(CA-cIAI组),HA-cIAI 216例(HA-cIAI组)。比较两组患者的一般资料、治疗情况及实验室指标,对HA-cIAI进行相关危险因素分析。结果:与CA-cIAI组比较,HA-cIAI组≥60岁的患者比例增高、平均住院时间延长、腹部恶性肿瘤及住院期间行腹部手术患者比例增加、血红蛋白与降钙素原水平降低,而谷丙转氨酶水平升高(均P0.05);两组住院期间行腹部手术的患者中,HA-cIAI组手术持续时间≥3 h、术中出血量≥200 mL、留置腹腔引流管时间≥10 d、留置导尿管及留置时间≥7 d和术前使用抗菌药物患者的比例均明显高于CA-cIAI组(均P0.05)。Logistic回归分析显示,住院时间≥15 d(OR=6.946,95% CI=3.786～12.743,P0.05)及腹部恶性肿瘤(OR=2.880,95% CI=1.538～5.390,P0.05)是HA-cIAI的独立危险因素。结论:中老年、腹部恶性肿瘤、住院时间长及手术持续时间长、术中出血量大、留置腹腔引流管时间长、留置导尿管及留置时间长和术前使用抗菌药物,特别是住院时间≥15 d及腹部恶性肿瘤为HA-cIAI的危险因素,对于有以上因素的患者,需根据情况采取有效的预防措施,以防HA-cIAI的发生。     

腹腔镜下胃癌根治术患者发生医院感染的病原菌分布及危险因素分析

目的 分析腹腔镜下胃癌根治术患者发生医院感染的病原菌分布及危险因素。方法 选取2018年1月至2022年9月本院收治的行腹腔镜手术治疗的胃癌患者86例，通过对所有患者一般资料情况进行记录统计，分析其术后发生医院感染的病原菌分布情况及危险因素。结果 行手术治疗的86例患者中术后出现医院感染的患者有8例，感染率为9.3%；其中5例为肺部感染，占5.8%，其次为腹腔感染与切口感染，分别为2例（2.33%）和1例（1.16%）。发生医院感染的8例患者共分离培养出病原菌11株，其中较多的为革兰阴性菌，共7株，占63.6%，其次为革兰阳性菌，共4株，占36.4%。经单因素分析结果显示，经腹腔镜手术治疗的患者术后发生医院感染的影响因素包括年龄、胃癌分期、吸烟史、糖尿病史、手术时间、住院时间、留置尿管时间，差异均具有统计学意义（P<0.05）；通过对上述影响因素进行多因素Logistic回归分析显示，术后患者发生医院感染的独立危险因素包括年龄≥70岁、吸烟史、糖尿病史、手术时间≥3 h(P<0.05)。结论 腹腔镜下胃癌根治术患者有一定医院感染率，其中主要以革兰阴性菌为主；发生感染的独立因...     

急诊腹部外科手术患者发生静脉血栓栓塞症的危险因素分析

目的:探讨急诊腹部外科手术后静脉血栓栓塞症发生的危险因素。方法 :回顾性分析2014年6月至2019年6月就诊于利津县中医院接受急诊腹部外科手术的480例患者的临床资料,根据发生静脉血栓栓塞症与否分为病例组与对照组,对两组患者的临床资料进行单因素分析、Logistic回归分析。结果:两组患者体质指数、吸烟史例数、合并高血压例数、合并冠心病例数、术中出血量、住院时间、麻醉方式、输血例数、再次手术例数、留置引流管例数、血小板计数、凝血酶原时间、纤维蛋白原、纤维蛋白原降解产物水平比较差异无统计学意义(P0.05);两组患者年龄、性别、合并糖尿病例数、手术时长、术后卧床时间、手术方式、手术部位、活化部分促凝血酶原激酶时间、D-二聚体、超敏C反应蛋白水平差异有统计学意义(P0.05)。Logistic回归分析结果显示,性别(女)、合并糖尿病、白细胞计数≥10×109/L、活化部分促凝血酶原激酶时间30 s、超敏C反应蛋白≥5 mg/L、腹腔镜手术、术后卧床时间≥48 h、胃肠手术、手术时长≥3 h为急诊腹部外科手术患者发生静脉血栓栓塞症的独立危险因素(P0.05)。结论:女性、合并糖尿病、白细胞计数≥10×109/L、活化部分促凝血酶原激酶时间30 s、超敏C反应蛋白≥5mg/L、腹腔镜手术、术后卧床时间≥48 h、胃肠手术、手术时长≥3 h为急诊腹部外科手术患者发生静脉血栓栓塞症的独立危险因素,此类患者术后应重点关注。     

老年患者日间手术腹腔镜胆囊切除延迟出院的危险因素分析

目的探讨老年患者日间手术腹腔镜胆囊切除(day-surgery laparoscopic cholecystectomy,LC/DS)延迟出院的危险因素。方法回顾性分析2009年11月至2015年7月解放军总医院710例老年患者LC/DS的临床资料,分析延迟出院的原因及危险因素。结果 710例患者中,566例(79.7%)于术后24 h内出院,144例(20.3%)延迟出院,无死亡患者。延迟出院的原因包括心理因素、并发症、留置腹腔引流管、中转开腹手术。年龄(P=0.025)、心律失常病史(P=0.016)及胆囊慢性炎症(P0.001)是因心理因素延迟出院的独立危险因素,手术时间≥60 min(P=0.002)、术中出血量≥15 ml(P=0.003)、胆囊急性炎症(P=0.001)及胆囊壁厚度≥3 mm(P=0.016)是留置腹腔引流管延迟出院的独立危险因素。结论年龄、心律失常病史、手术时间≥60 min、术中出血量≥15 ml、胆囊慢性炎症、胆囊急性炎症及胆囊壁厚度≥3 mm是老年患者LC延迟出院的独立危险因素。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.