LC-MS/MS法测定大鼠血浆中芫花素的浓度及药物动力学研究

目的 建立LC-MS/MS方法测定芫花素在大鼠体内的血药浓度,并研究其药物动力学。方法 大鼠灌胃芫花提取物,眼眶采血,离心,以蛋白沉淀法处理血浆样品,芒柄花素为内标,电喷雾离子化,多反应检测方式进行负离子检测,检测离子质荷比(m/z)分别为283.2/267.9,267.0/251.9。使用Phenomenex Gemini 110 C18色谱柱(50 mm×2.0 mm,5 μL);以甲醇- 0.1 %甲酸水(85∶15)为流动相,等度洗脱;柱温:40 ℃;流速:0.3 mL·min-1。结果 大鼠灌胃芫花提取物后的药-时曲线符合二房室模型,芫花素血药浓度在5～1000 ng·mL-1范围内线性关系良好(r2=0.998),最低检测限(LOQ)为0.5 ng·mL-1,日内及日间精密度(RSD)为2.42 %～10.71 %,日内及日间准确度为95.67 %～112.15 %,血浆中无内源性基质干扰,稳定性良好。结论 本研究所建立的方法简便、灵敏、重复性好、分析速度快,可用于血浆样品中芫花素的血药浓度测定和大鼠体内药物动力学研究。     

Improvement in cardiac function after sarcoplasmic reticulum Ca2+-ATPase gene transfer in a beagle heart failure model

Background Heart failure （HF） is a major cause of morbidity and mortality worldwide, but current treatment modalities cannot reverse the underlying pathological state of the heart. Gene-based therapies are emerging as promising therapeutic modalities in HF patients. Our previous studies have shown that recombinant adeno-associated viral （rAAV） gene transfer of Sarco-endoplasmic reticulum calcium ATPase （SERCA2a） can be effective in treating rats with chronic heart failure （CHF）. The aim of this study was to examine the effects of SERCA2a gene transfer in a large HF animal model. Methods HF was induced in beagles by rapid right ventricular pacing （230 beats/min） for 30 days. A reduced rate ventricular pacing （180 beats/min） was continued for another 30 days. The beagles were assigned to four groups： （a） control group （n=4）; （b） HF group （n=4）; （c） enhanced green fluorescent protein group （n=4）; and （d） SERCA2a group （n=4）. rAAV1-EGFP （1×10^12 μg） and rAAV1-SERCA2a （1×10^12 μg） were delivered intramyocardially. SERCA2a expression was assessed by Western blotting and immunohistochemistry. Results Following 30 days of SERCA2a gene transfer in HF beagles its protein expression was significantly higher than in the HF group than in the control group （P 〈0.05）. Heart function improved along with the increase in SERCA2a expression. Left ventricular systolic function significantly improved, including the ejection fraction, left ventricular systolic pressure, maximal rate of rise of left ventricular pressure （＋dp/dtmax）, and the maximal rate of decline of left ventricular pressure （-dp/dtmax） （P 〈0.05）. Left ventricular end-diastole pressure significantly decreased （P 〈0.05）. The expression of SERCA2a in the myocardial tissue was higher in the SERCA2a group than in the HF group （P〈0.05）. Conclusions Intramyocardial injection of rAAV1-SERCA2a can improve the cardiac function in beagles induced with HE We expect further studies on SERCA2a＇s long-term safety, efficacy, dosage and the optimization before using it in humans with HF.     

新生儿坏死性小肠结肠炎的危险因素及早期临床特点

  目的  探讨新生儿坏死性小肠结肠炎（NEC）发生的危险因素及其早期临床特点，提高NEC的早期预警、尽早干预，从而提高NEC的预后。  方法  收集2017年11月22日—2020年11月22日在云南省第一人民医院儿科NICU确诊为NEC的患儿95例，按照1∶1配对比例，选取同期95例非NEC患儿作为对照组，对临床资料进行回顾性分析，单因素变量采用χ2 检验，筛选可能对NEC发生有影响的因素，再对其进行多因素Logistic回归分析，计数资料采用t检验、秩和检验，等级资料运用Spearman秩相关检验等统计学方法，α= 0.05。  结果  提示早产、低出生体重、感染、机械通气是NEC的独立高危因素，早期以腹胀、胃潴留为主要临床表现，白细胞及中性粒细胞与NEC的严重程度无明显相关性，C反应蛋白及降钙素原与疾病的严重程度成正相关，淋巴细胞及血小板与病情严重程度成负相关（P < 0.05），腹部立位X片对NEC早期诊断无明显特异性。  结论  当患儿存在早产、低出生体重、感染、机械通气危险因素时，且出现腹胀、吃奶欠佳表现，同时伴有C反应蛋白及降钙素原升高，需警惕NEC的发生，并动态行腹部立位X片，提高早期诊断率。     

The pulmonary bioprosthetic heart valve: its unsuitability for use as an aortic valve replacement

BACKGROUND AND AIM OF THE STUDY: The porcine pulmonary bioprosthetic heart valve represents an alternative means of aortic valve replacement (AVR), though knowledge of its biomechanical function and characteristics is limited. The valve has potential advantages over the aortic bioprosthesis; notably, it lacks the muscular shelf of the right coronary cusp of the latter bioprosthesis. The study aim was to investigate the suitability of the porcine pulmonary bioprosthetic valve for AVR. METHODS: Porcine pulmonary and aortic roots were zero pressure-fixed with 0.5% buffered glutaraldehyde, characterized, and compared with fresh porcine pulmonary and aortic roots. The in-vitro analysis included assessment of mechanical properties, hydrodynamic function, geometry of the pulmonary root, and durability. RESULTS: The fixed pulmonary roots and fresh aortic roots were similar in certain aspects of mechanical response, notably leaflets in the radial direction and the root wall. The fixed pulmonary root was slightly more compliant than the fixed aortic root, and this led to an improvement in forward flow hydrodynamic function. The reverse flow hydrodynamic function of the pulmonary roots was poor; fresh pulmonary roots exhibited a trivial closed valve regurgitant volume. On fixation, this characteristic was aggravated, leading to a gross closed valve regurgitant volume in 50% of all fixed pulmonary roots. The cause of leakage was identified as a prolapsed anterior leaflet. Durability of the fixed pulmonary root was also inferior to that of the fixed aortic root; three fixed pulmonary roots subjected to accelerated fatigue testing showed signs of leaflet macroscopic damage. CONCLUSION: Overall, the performance of the porcine pulmonary bioprosthesis was far inferior to that of the currently used porcine aortic bioprosthesis. Hence, the porcine pulmonary bioprosthetic valve was deemed unsuitable for AVR.     

Effects of repetitive bolus injections of zymosan-activated plasma on lung mechanics and airway responsiveness in awake sheep

We studied the pulmonary effects of repetitive bolus injections of autologous zymosan-activated plasma (ZAP) in nine chronically instrumented awake sheep. Aerosol histamine responsiveness was determined 1 h before and 4.5 h after the first bolus injection of ZAP. Each sheep received in the pulmonary artery a total of eight 5-ml bolus injections of ZAP separated by 30 min. On a separate day, with the order of experimentation varied to avoid sequential bias, six of the nine sheep also received "control" plasma (plasma prepared in the identical fashion as ZAP but not incubated with zymosan). "Control" plasma caused reproducible transient increases in pulmonary artery pressure, but it did not cause alterations in any of the other measured variables. Repetitive bolus injections of ZAP caused reproducible alterations in lung mechanics, pulmonary hemodynamics, lung fluid and solute exchange, oxygenation, and peripheral leukocyte counts. The increases in thromboxane-B2 concentrations in lung lymph and plasma were greatest after the first bolus injection of ZAP, with the magnitude of these changes diminishing on succeeding injections of ZAP. Aerosol histamine responsiveness did not increase after the eight bolus injections of ZAP.     

关节镜下经皮空心钉固定治疗急性移位单纯性肱骨大结节骨折

目的探讨关节镜下空心钉固定治疗急性移位单纯性肱骨大结节骨折的方法及近期疗效。方法2010年1月-2013年2月,采用关节镜下空心钉固定治疗15例急性移位单纯性肱骨大结节骨折患者。其中男8例,女7例;年龄31~66岁,平均44.9岁。均由摔伤致病。受伤至手术时间4~19 d,平均9.9 d。术前肩关节活动度:前屈上举(74.13±17.19)°、外展(121.67±17.50)°、内旋(T11±2)°、外旋(39.27±8.08)°。术前疼痛视觉模拟评分(VAS)为(6.46±1.30)分,Costant评分为(62.27±11.90)分。结果术后切口均I期愈合。15例均获随访,随访时间12~27个月,平均15个月。复查X线片示骨折对位、对线良好,骨折均愈合,愈合时间6~13周,平均8周。末次随访时肩关节活动度为:前屈上举(169.33±7.99)°、外展(156.67±10.47)°、内旋(T6±2)°、外旋(71.67±7.94)°,与术前比较差异均有统计学意义(P0.05);末次随访时VAS为(1.73±1.02)分,Costant评分为(96.20±2.34)分,与术前比较差异均有统计学意义(t=—8.51,P=0.00;t=11.50,P=0.00)。随访期间无内固定物失效、骨折移位、神经或血管损伤以及肩关节粘连等并发症发生。结论关节镜下空心钉固定治疗急性移位单纯性肱骨大结节骨折近期疗效好、创伤小、恢复快,是一种安全可靠的治疗方法。