老年糖尿病患者骨密度与血尿酸水平的相关研究

目的横断面观察老年2型糖尿病(type 2 diabetes mellitus,T2DM)患者骨密度及血尿酸水平,探讨两者之间的相关性。方法选择明确诊断为T2DM且年龄在60岁以上的患者254例,搜集患者资料,分别行骨密度测定,依据T值水平将患者分为骨量正常组(n=89例),骨量减少组(n=86例)及骨质疏松组(osteoporosis,OP,n=79例);依据血尿酸水平将患者分为高尿酸血症组(血尿酸≥420μmol/L)和血尿酸正常组(血尿酸420μmol/L)。结果 (1)老年T2DM男性患者血尿酸及各部位骨密度值均高于女性,OP患病率低于女性,差异具有统计学意义(P0.05)。(2)男性患者血尿酸与腰椎1至4联合值(the lumbar vertebrae,L1-4)及Wards三角部位的骨密度呈正相关(r=0.366,P=0.009;r=0.367,P=0.008),女性患者血尿酸与各部位骨密度无明显相关性(P0.05)。(3)高尿酸血症组患者的血尿酸与股骨颈及大转子部位的骨密度呈负相关(r=-0.374,P=0.025;r=-0.535,P=0.001),血尿酸正常组血尿酸与股骨颈部位的骨密度呈正相关(r=0.212,P=0.010)。结论老年T2DM患者骨密度受性别及血尿酸水平的影响,正常偏高水平的血尿酸有利于稳定骨量。     

沈阳市2697名健康体检者超声跟骨骨密度调查分析

目的 了解沈阳地区健康男、女的骨密度情况。方法 回顾性分析2008~2010年中国医科大学附属盛京医院体检中心体检的1216名女性和1481名男性沈阳市健康体检者的骨密度，检测方法为定量超声跟骨骨密度测定。结果 女性平均T值-1.216±0. 960，男性平均T值-0.750±1. 028,二者差异显著；女性骨质疏松93例，占7.65%.，骨量减少663例，占52. 56%;男性骨质疏松37例，占 2.5%，骨量减少616例，占41.59%_。结论 女性各年龄段T值均低于男性，随着年龄增加，男女T值 均逐渐下降，进入围绝经期后女性T值下降更为迅速，定量超声跟骨骨密度测定可以作为骨量减少及骨质疏松的筛查手段。     

骨折风险评估工具（FRAX® )在评价绝经后女性骨密度的临床意义

目的探讨骨折风险评估工具(FRAX)在评价绝经后女性骨密度变化中的作用。方法 2014年12月至2015年12月完成双能X线骨密度测定的绝经后女性166例,问卷采集信息,应用FRAX计算代入或不代入股骨颈骨密度时各研究对象10年内骨质疏松性骨折概率,并结合骨密度测定结果、OSTA及IOF 1 min测试题进行统计学分析。结果 1骨量异常组年龄较高、体重较轻、BMI较低、身高变化较多、绝经年限较长,两组间具有既往骨折史的人数差异有统计学意义。2有或无BMD时,骨量异常组10年内骨质疏松性骨折概率均显著高于骨量正常组。3有或无股骨颈BMD时,FRAX预测值与股骨颈骨密度T值之间均呈显著负相关,而有和无股骨颈BMD的FRAX预测值之间呈显著正相关。4随着年龄或骨质疏松风险的增长,骨量异常发生率逐渐上升,10年内骨质疏松性骨折概率显著升高。5不代入BMD时,10年内主要骨质疏松性骨折概率识别骨量异常的ROC曲线的AUC为0.705(P0.001),cutoff值为3.75%,准确度为中等;10年内髋骨骨折概率识别骨量异常的ROC曲线的AUC为0.743(P0.001),cutoff值为1.75%,准确度中等。结论 FRAX能够反映机体骨密度变化,全面评估骨折风险,并可作为一项基本的筛检工具,应用于识别绝经后女性骨质疏松的高危人群。     

腰椎松质骨CT值与年龄、双能X线骨密度值相关性研究

目的研究女性腰椎松质骨CT值与年龄、双能X线骨密度值的相关性。方法 103例女性住院患者纳入研究对象,所有患者行腰椎骨密度与腰椎螺旋CT检查,双能X线骨密度仪(DXA)测量腰1~4椎体骨密度(BMD)和T值。CT扫描分析腰1~4椎体松质骨CT值。将所有研究对象的年龄、腰1~4椎体CT值、DXA测得BMD值及T值进行收集、整理及统计学处理。结果 1不同年龄段腰1~4椎体松质骨CT值差异具有统计学意义(F=102.5,P0.001);每两个年龄段间的CT值比较差异亦具有统计学意义(P0.001)。组内比较腰1~4椎体之间的CT值没有统计学意义(P0.05)。2按T值将所有研究对象分为3组(骨量正常、骨量减少及骨质疏松症组),各组间腰1~4椎体松质骨CT值差异具有统计学意义(F=248.6,P0.001)。组间两两比较,骨质疏松症组CT值骨量减少组CT值骨量正常组CT值,差异具有统计学意义(P0.001)。组内比较腰1~4椎体的CT值没有统计学意义(P0.05)。3腰1~4椎体BMD值与椎体松质骨CT值呈显著正相关(P0.001)。结论女性腰椎椎体的松质骨CT值随着年龄增长逐渐减低。DXA测得BMD值与腰椎椎体松质骨CT值存在显著正相关。     

胰岛素样生长因子与血液透析患者骨质疏松症关系的研究

目的：探讨血胰岛素样生长因子-1（IGF-1）与血液透析患者骨密度的关系及其在骨质疏松症诊断中的作用。方法：45例骨量异常（骨量减少或骨质疏松）血液透析患者分别检测透析前血IGF-1、Ⅰ型前胶原氨基端前肽（PINP）、Ⅰ型胶原C末端肽（CTX）等生化指标,统计所有患者的骨密度值。15例骨量正常血液透析患者作为对照组。结果：透析患者骨量异常组血IGF-1水平显著低于骨量正常对照组（P〈0.001）,而且早在骨量减少阶段就已显示出差异性（P〈0.05）,血PINP、CTX显著高于骨量正常对照组（P〈0.001）。血清IGF-1水平与患者髋部的骨密度正相关（P〈0.001）,与PINP、CTX负相关（P〈0.001）,但与腰椎骨密度值无相关性。结论：IGF-1做为新型骨代谢生化标志物,其水平在血液透析患者中与骨密度变化相平行,对透析患者骨量变化的监测和骨质疏松症的早期诊断具有重要的临床价值。     

新疆乌鲁木齐市某社区维吾尔族女性跟骨骨密度与代谢综合征相关性分析

目的探索代谢综合征(MS)与不同年龄及代谢状态下维吾尔族女性定量骨超声检测跟骨骨密度(T值)与其之间的相关性。方法横断面研究,对象为新疆乌鲁木齐市二道桥某社区常住维族女性。按年龄分组,观察不同年龄段维族女性骨量的变化。按中华医学会糖尿病分会(CDS)[1]诊断MS的诊断标准,将549名女性分为高血压组136例,血压正常组413例;糖尿病组103例,血糖正常组446例;单纯肥胖或超重组290例,体重正常组259例;血脂紊乱组157例,血脂正常组392例;MS组86例,非MS组463例。根据既往史是否绝经分为未绝经组339例,绝经组182例;并用线性回归分析,研究跟骨骨密度的独立影响因素。结果高血压、糖代谢异常、MS组骨量T值均低于其代谢正常组,差异有统计学意义(均P0.05);高血压、糖代谢异常、超重或肥胖、MS组骨量减少、骨质疏松的患病率均高于其代谢正常组,差异有统计学意义(均P0.05);按年龄分组,不同组间T值不完全相同,随年龄增长,骨量减少的患病率升高,差异有统计学意义(P0.05);按是否合并绝经分组,绝经组骨量减少、骨质疏松的患病率明显升高,差异有统计学意义(P0.05)。结论 MS作为多种代谢异常的症候群,骨量减少的患病率高,是骨质疏松发生的高风险人群。绝经是女性骨量减少的独立危险因素。     

新疆老年男性骨转化生化标志物及性激素与骨质疏松症的相关性研究

目的探讨新疆老年男性骨转换生化标志物及性激素水平与原发性骨质疏松症的关系。方法采用双能X线骨密度仪检测146例老年男性患者腰椎、左侧股骨骨密度(BMD),平均年龄:72.4±7.9岁,基于骨密度T值分为骨量正常组(75例)和骨量异常组(71例),采用酶联免疫法测定Ⅰ型前胶原氨基端原肽(PINP)和Ⅰ型胶原C末端肽(CTX),放射免疫法测定雌二醇(E2)和睾酮(T),比较两组骨转换生化指标和性激素水平是否存在差异及其与骨密度的相关性。结果 1 PINP与CTX在骨量正常组和骨量异常组差异均无统计学意义(P0.05);两者偏相关分析呈显著正相关(r=0.746 P=0.000)。2雌二醇、睾酮在两组中比较,差异有统计学意义(P0.05)。骨量异常组雌二醇(17.48±7.61)低于骨量正常组(21.31±11.43),t=2.391,P=0.018;骨量异常组睾酮(3.50±1.02)低于骨量正常组(3.98±1.43),t=2.331,P=0.021。3汉族人群左侧髋关节骨密度高于维吾尔族人群,除Inter Tro部位外,差异均有统计学意义(P0.05);年龄与髋关节各部位骨密度呈显著负相关。结论性激素水平降低可能是影响男性骨量减少的一个重要危险因素,而雌激素可能占主要地位;随着年龄的增加,老年男性髋关节骨密度呈下降趋势,测定左侧髋关节骨密度对诊断骨质疏松症有着重要意义。     

骨质疏松症风险一分钟测试在评价绝经后女性超声骨 密度变化中的作用

目的探讨骨质疏松症风险一分钟测试在评价绝经后女性跟骨超声骨密度变化中的作用。方法对273名门诊就诊的绝经后妇女进行骨质疏松风险一分钟测试,并采用韩国SONOST 3000超声波骨密度检测仪测定受试者右跟骨SOS值、BUA值、BQI值及T值,按问卷测试结果对各组进行统计学分析。结果问卷测试阳性组受试者年龄较高(P0.01)、身高较低(P0.05)、体重较轻(P0.01),跟骨定量超声各参数及骨密度T值均显著低于阴性组(P0.01)。随年龄或OSTA风险增加,测试结果阳性率升高(P0.05),骨密度T值显著降低(P0.05)。在所有测试问题中,问题2和问题4阳性回答受试者的BQI值及骨密度T值均明显低于阴性回答受试者,差异具有统计学意义(P0.05)。结论骨质疏松症风险一分钟测试可以简便、有效地反映骨质疏松骨密度改变,特别对于测试问题2或问题4阳性的绝经后女性应引起高度警惕,建议及早诊治。     

绝经后女性膝关节骨性关节炎与胫骨软骨下骨骨密度的相关性研究

目的评价绝经后女性膝关节骨性关节炎与胫骨软骨下骨骨密度的相关性。方法选取2017年7月至2017年10月就诊于新疆医科大学第一附属医院的绝经后膝关节骨性关节炎女性80例,年龄45~92(65.2±10.9)岁。按照KellgrenLawrence诊断标准将Ⅰ、Ⅱ、Ⅲ、Ⅳ级KOA分为A、B、C、D等4个组。将胫骨内侧及外侧选为感兴趣区(regions of interest,ROI)分别标记为ROI 1,ROI 2。采用GE Lunar Prodigy型双能X线骨密度仪分别测量两个ROI骨密度,同时测量股骨颈及腰椎骨密度。结果共纳入骨性关节炎患者80例。ROI 1平均骨密度值0.66±0.24 g/cm~2,ROI 2平均骨密度值0.46±0.19 g/cm~2,腰椎平均骨密度值0.76±0.15 g/cm~2,股骨颈平均骨密度值0.75±0.14 g/cm~2。ROI 1、ROI 2、股骨颈及腰椎骨密度值与KOA分级比较后发现,ROI 1、ROI 2、股骨颈骨密度值在4组间差异有统计学意义(P0.05),腰椎骨密度差异没有统计学意义(P0.05)。胫骨软骨下骨骨密度与KOA分级、年龄、腰椎骨密度、股骨颈骨密度进行相关性分析后发现,胫骨软骨下骨骨密度与KOA分级、年龄呈负相关,与腰椎及股骨颈骨密度呈正相关。结论随KOA的进展,胫骨软骨下骨皮质终板硬化,但其下方的松质骨骨密度减低。     

辛伐他汀对绝经伴血脂代谢异常女性跟骨骨密度的影响

目的 研究辛伐他汀对绝经后伴血脂代谢异常女性跟骨骨密度的影响。方法 分析885名绝经后口服辛伐他汀治疗血脂代谢异常（TC>5.18mmol/L 或 LDL-C> 3.37mmol/L）女性的跟骨骨密度,并依据T值分为骨质正常、骨量减少、骨质疏松。结果 治疗前跟骨骨密度为305.3± 59.2 mg/cm2,骨质正常、骨量减少、骨质疏松的人数分别为115、446、324,口服辛伐他汀（20mg/d）治疗3月后骨密度为309.7±56.3 mg/cm2,骨质正常、骨量减少、骨质疏松的人数为117、459、319,12月后跟骨骨密度为312.5±60.9 mg/cm2,骨质正常、骨量减少、骨质疏松的人数为122、460、303。结论 绝经后伴血脂代谢异常女性应用辛伐他汀（20mg/d）治疗12个月后跟骨骨密度增高,但对骨质疏松患病风险无影响。     

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.