烧伤患者血浆D-乳酸水平和肠道内IgA含量的变化

目的　探讨大面积烧伤患者肠道屏障损伤的规律。方法　采用分光光度法和酶联法分别测定16例大面积烧伤患者血浆D 乳酸水平和肠道内免疫球蛋白A(IgA)含量。结果　伤后血浆D 乳酸水平明显升高 ,各时相点均明显高于健康对照 ,并于伤后第 3周达到最高点 ;同期肠道内IgA含量明显减少 ,于伤后的第 2周达到最低点 ;烧伤面积 >5 0 %的患者上述指标的变化幅度大于烧伤面积 <5 0 %的患者。结论　烧伤后肠道屏障的损伤涉及机械屏障和免疫屏障等多方面 ;应采用不同的方法、从不同角度入手保护烧伤患者肠道屏障。     

胃肠外科术后肠道细菌移位的临床研究

目的 探讨胃肠外科手术后肠黏膜屏障损伤与肠道细菌移位(BT)及BT与感染并发症之间的关系.方法 34例择期胃肠外科手术患者,于术前2h和术后2、24、48h采集外周血,进行全血细菌DNA、血D-乳酸、内毒素(LPS)浓度检测及血细菌培养.观察患者30天以监测感染并发症情况.结果 术前PCR检测全血细菌DNA均为阴性,术后共有7例阳性.术后出现全身炎症反应综合征(SIRS)的患者PCR阳性率为38.9%,无SIRS组为0%(P＜0.01).PCR阳性组SIRS发生率为100%,阴性组为40.7%(P＜0.01).PCR阳性者85.7%发生感染并发症,阴性者无一发生(P＜0.01).术后血细菌培养阳性率5.9%,显著低于PCR的检测结果(20.6%,P＜0.01);血培养阳性者,PCR检测均呈阳性.PCR阳性结果中大肠杆菌DNA占71.4%.PCR阳性的患者外周血血浆D-乳酸及LPS浓度较PCR阴性者明显升高(P＜0.01),且二者呈显著正相关(r＝0.89,P＜0.01).结论 胃肠外科术后肠黏膜屏障损伤与BT关系密切,术后早期(2h)即可发生BT,以大肠杆菌为主,术后SIRS和感染并发症与BT密切相关.     

谷氨酰胺治疗急性胰腺炎肠屏障功能障碍临床观察

目的探讨谷氨酰胺在急性胰腺炎肠屏障功能障碍患者中的治疗作用。方法所有病例来自2011年3月-2012年9月在本院住院的患者62例,其诊断符合急性胰腺炎肠屏障功能障碍标准。随机分为对照组32例和治疗组30例,对照组采用常规治疗方法,治疗组在常规治疗方法的基础上,加用丙氨酰谷氨酰胺静脉注射治疗。分别记录两组腹部胀痛消失时间,检测治疗前后血液内毒素（LPS）浓度及尿乳果糖／甘露醇比值（L／M）。结果对照组腹部胀痛消失时间为（8．12±0．97）d,治疗组为（6．40±1．03）d,治疗组腹部胀痛消失时间明显短于对照组;治疗后治疗组LPS水平及IMM值较对照组低。结论在常规治疗急性胰腺炎肠屏障功能障碍患者时,加用丙氨酰谷氨酰胺可取得更好的疗效。     

小肠RNA对60Coγ射线照射后小鼠肠黏膜屏障及细菌移位的影响

目的探讨小肠RNA对受γ射线照射小鼠肠黏膜屏障及细菌移位的影响.方法选用BALB/c雄性小鼠28只,用11.50 Gy^60 Co γ射线进行腹部一次照射,于照后1～3 h采用局部肠腔扩张注入法给小鼠空肠肠腔内注入正常大鼠小肠RNA,于照后5 d活杀,取空肠段、肠系膜淋巴结,进行肠黏膜组织形态的观察、肠腺存活率及细菌移位率的测定.所有数据经SPSS 13.0统计处理.结果（1）小肠RNA可明显提高腹部照射小鼠空肠的肠腺存活率（P＜0.01）;（2）光镜和扫描电镜结果显示照射对照组小肠绒毛萎缩、塌陷,黏膜下水肿,肠腺结构破坏,部分细胞变性坏死,RNA组肠黏膜形态结构明显好于照射对照组;（3）小肠RNA可降低受照射小鼠肠道细菌移位率.结论小肠RNA可改善小鼠肠黏膜屏障功能,减少细菌移位.     

腹部外科手术操作对大鼠肠道运动功能和肠神经系统的影响

目的 观察不同的腹部外科手术操作对大鼠肠道运动功能以及肠神经系统内乙酰胆碱酯酶(AchE)神经元和一氧化氮合酶(NOS)神经元的影响,探讨腹部外科手术对肠道运动功能影响的神经机制.方法 48只SD大鼠随机分为单纯开腹组、肠道按摩组、肠道手术组和正常对照组(n=12),各组术后灌服炭末,测定小肠炭末推进率,同时取各组相同部位的小肠和大肠,制作肠肌间神经丛铺片标本,采用AchE和NADPH-d组化染色观察AchE、NOS阳性神经元的分布密度和染色情况.结果 炭末推进率(%)肠道手术组、肠道按摩组低于单纯开腹组和正常对照组(P＜0.01),肠道手术组低于肠道按摩组(P＜0.05),单纯开腹组与对照组比较降低不明显(P＞0.05);与正常对照组比较,肠道手术组、肠道按摩组的小肠和大肠肌间神经丛内AchE阳性神经元数量(个/200倍视野)减少(P＜0.01),阳性表达减弱,NOS阳性神经元数量增多(P＜0.01),阳性表达增强,节间束纤维粗大,而单纯开腹组的变化不明显;与肠道按摩组比较,肠道手术组小肠和大肠肌间神经丛内的NOS阳性神经元数量较多(P＜0.01),胞体大而染色深,节间束纤维较粗大,而AchE阳性神经元数量和染色的差异不明显.结论 腹部外科手术在一定程度上会影响或损伤肠神经系统的胆碱能和氮能神经,这可能是腹部外科手术后发生肠道运动功能障碍的神经机制之一.     

Vascular volume and blood-brain barrier permeability measured by dynamic contrast enhanced MRI in hippocampus and cerebellum of patients with MCI and normal controls

PURPOSE: To measure the cerebrovascular volume and blood-brain barrier (BBB) permeability indices in hippocampus and cerebellum of patients with mild cognitive impairment (MCI) using dynamic contrast-enhanced MRI (DCE-MRI), and compare to that of normal controls. MATERIALS AND METHODS: A total of 11 MCI subjects and 11 healthy elderly controls participated in this prospective study. DCE-MRI was performed to measure the contrast enhancement kinetics. The early enhancement percentage (at 50 seconds after injection) was defined as the vascular volume index, and the ratio between the four to five-minute enhancement relative to the 50-second enhancement was defined as the BBB permeability index. RESULTS: The enhancement kinetics measured from hippocampus of MCI individuals demonstrated a lower magnitude and slower decay than healthy controls, suggesting that they had a smaller vascular volume (significant in the right side; P <0.001) and a higher BBB permeability (not reaching significance level). The vascular volume index was significantly correlated with naming ability (P 0.05). CONCLUSION: These results suggest that changes in cerebrovasculature may occur in hippocampus of MCI. DCE-MRI may provide a noninvasive means to measure the subtle BBB leakage associated with the cerebrovascular pathology commonly found in Alzheimer's disease.     

Metabolic disturbances in liver 1H MR spectroscopy in HIV and HCV co-infected patients as a potential marker of hepatocyte activation

Purpose: To evaluate proton magnetic resonance spectroscopy (¹H MRS) features in order to assess hepatocellular activation in chronic hepatitis C and human immunodeficiency virus/hepatitis C (HIV/HCV) co-infected patients. Material and Methods: Liver in vivo ¹H MR spectra were obtained in 14 patients with hepatitis C virus infection (HCV), 20 HIV/HCV co-infected individuals, and 24 healthy volunteers. Resonances of lipids, glutamine/glutamate (Glx), phosphomonoesters (PME), glycogen/glucose (Glc) were assessed and metabolite ratios to total lipids (TL) were calculated. Results: A significant increase in Glx/TL and PME/TL was observed in the HCV group as compared to healthy individuals. Patients with HIV and HCV co-infection had a further increase of all metabolite ratios. Changes in metabolite ratios were due to both the increase in particular metabolite contents and to the decrease in lipid levels. HIV/HCV-infected patients treated with highly active anti-retroviral therapy (HAART) showed elevated PME and Glx levels and significantly decreased TL compared to patients not undergoing anti-retroviral treatment. Conclusions: Our findings suggest clinical usefulness of liver ¹H MR spectroscopy in detecting even slight disturbances in liver metabolism.     

Right ventricular outflow tract obstruction as a confounding factor in the assessment of the impact of pulmonary regurgitation on the right ventricular size and function in patients after repair of tetralogy of Fallot

Purpose:

To compare right ventricular (RV) size and function between patients with combined pulmonary regurgitation (PR) plus RV outflow tract (RVOT) obstruction (RVOTO) and patients with isolated PR.

Materials and Methods:

Consecutive individuals with significant PR (PR fraction ≥20%) after tetralogy of Fallot (TOF) repair who underwent cardiovascular magnetic resonance (CMR) were included. Patients with additional hemodynamic abnormalities (residual ventricular septal defect, extracardiac shunt, and/or more than mild regurgitation at a valve other than the pulmonary valve) were excluded. Significant RVOTO was defined as peak gradient across RVOT ≥30 mmHg.

Results:

Significant differences between patients with combined PR+RVOTO (n = 9) and isolated PR (n = 33) were observed in RV end‐diastolic volume (138.6 ± 25.1 vs. 167.0 ± 34.6 mL/m², P = 0.02, respectively), RV end‐systolic volume (65.0 ± 9.6 vs. 92.7 ± 26.2 mL/m², P = 0.003), and RV ejection fraction (RVEF) (52.8 ± 3.7 vs. 45.0 ± 6.4%, P = 0.001). Both PR and peak RVOT gradient were independent predictors of RV size.

Conclusion:

Patients with combined PR+RVOTO had smaller RV volumes and higher RVEF when compared with patients with isolated PR. The confounding effect of RVOTO on RV size and function needs to be considered in CMR studies evaluating patients after TOF repair. J. Magn. Reson. Imaging 2011;33:1040–1046. © 2011 Wiley‐Liss, Inc.