甜茶素提取物对STZ致高血糖大鼠的降血糖作用研究

目的 :　研究甜茶素提取物对 STZ致高血糖大鼠的降血糖效果及其降糖机制。方法 :　腹腔注射 STZ制备糖尿病大鼠模型 ,取成型的大鼠随机分阳性对照组、甜茶素提取物组和降糖灵组。同时设一正常组。灌胃 3 w后 ,测血糖、果糖胺、胰岛素和 SOD等指标。结果 :　甜茶素提取物能极显著地降低 STZ致高血糖大鼠血糖 ,增强其抗氧化能力 ,同时能刺激胰岛素的分泌。结论 :　甜茶素提取物通过刺激胰岛素的分泌来降低血糖     

A Prospective,Randomized Comparison of Modified Pulmonary Vein Isolation Versus Conventional Pulmonary Vein Isolation in Patients with Paroxysmal Atrial Fibrillation

Modified Pulmonary Vein Isolation in AF Ablation. Introduction: Pulmonary vein isolation (PVI) is the primary ablation therapy in patients with atrial fibrillation (AF). We hypothesized that high dominant frequency (DF) sites (AF nests during sinus rhythm [SR]) adjacent to the PV ostia are associated with the atrial substrate that maintains AF, and PVI incorporating the high‐frequency AF nests may have a higher efficacy. Methods and Results: In a prospective and randomized comparison, 126 symptomatic paroxysmal AF patients that underwent PVI were enrolled. We compared the efficacy of a modified PVI (ablation line: 1.0–1.5 cm from the PV ostium with encircling the AF nests [spectral analysis with DF >70 Hz during SR, Group II]) versus the anatomy‐guided conventional PVI (Group I). In Group II, the DF value along the PV ostium was lower than 70 Hz after the PVI. The primary endpoint was the freedom from symptomatic atrial arrhythmias after a single procedure. We also followed the autonomic function by a time‐domain analysis of the heart rate variability. In both groups, AF nests were observed and electric isolation was successfully obtained in all patients. With a mean duration of 16 ± 6.1 months of follow‐up, Group II had a higher single procedure efficacy without drugs (78.7% vs 66.1%, log‐rank test: P = 0.02), and fewer repeat procedures (6.6% vs 23%; P = 0.04), as compared to Group I. Conclusion: PVI incorporating the high frequency AF nests adjacent to the PV ostia had a better single procedure efficacy. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1155–1162, November 2012)     

不同部位瘢痕疙瘩组织中IGF-I、IGF-IR的表达及其意义

目的 通过分析瘢痕疙瘩周围部和中央部组织中IGF-I、IGF-IR表达的差异,探讨瘢痕疙瘩呈浸润性生长的机制.方法 收集手术切除的瘢痕疙瘩组织8例及周围正常皮肤组织4例,对不同部位的瘢痕疙瘩组织和正常皮肤组织进行免疫组织化学染色,观察各组中IGF-I、IGF-IR的表达,比较瘢痕疙瘩不同部位和正常皮肤组织中IGF-I、IGF-IR表达的差异.结果 正常皮肤组织中成纤维细胞中IGF-I、IGF-IR的表达均呈阴性.瘢痕疙瘩周围组织成纤维细胞中IGF-I的表达明显高于中央部,差异有统计学意义(P<0.05);瘢痕疙瘩周围部组织纤维细胞中IGF-IR明显高于中央部,差异有统计学意义(P<0.05). 结论瘢痕疙瘩不同部位IGF-I、IGF-IR的表达差异可能是导致瘢痕疙瘩呈浸润性生长的机制之一.     

SARS冠状病毒N蛋白单克隆抗体的制备及鉴定

目的 制备SARS冠状病毒(SARS-CoV)N蛋白特异性单克隆抗体(McAb)，为SARS的快速诊断及致病机制的研究提供实验材料。方法 用纯化的重组SARS-CoVN蛋白免疫BALB/c小鼠，经细胞融合和亚克隆后获得分泌针对N蛋白的杂交瘤细胞株，用Western blot和间接免疫荧光法检测这些细胞株分泌的单克隆抗体特异性，并将N蛋白分3段表达初步定位单克隆抗体识别表位所在区域。结果 通过细胞融合和3轮克隆化，筛选出分泌抗N蛋白的6个杂交瘤细胞株。Western blot及免疫荧光显示，获得的McAb可与SARS-CoVN蛋白及SARS-CoV发生特异性反应，有4个细胞株分泌的抗体的识别位点位于N蛋白N端，2个位于C端。结论 获得了SARS-CoV特异性单克隆抗体并进行了初步定位，可用于SARS的早期诊断及致病机制研究。     

痔组织弹性纤维退变和血管生成的机制及其意义

目的研究痔组织弹性纤维的病理变化及微血管密度(MVD)和血管生成相关蛋白的表达与痔形成的关系。方法利用免疫组织化学染色技术(SP法),对比研究24例Ⅲ度痔患者的正常肛垫和痔两种组织内弹性纤维和MVD的变化,并检测一氧化氮合酶(NOS)的3种亚型、血管内皮生长因子(VEGF)和金属基质蛋白酶(MMP)2、MMP9在两种组织中表达的差异。结果痔组织存在显著的新生血管形成,痔组织与相对正常肛垫组织间的MVD计数、VEGF、MMP9表达差异存在统计学意义(P<0.05)。痔组织中iNOS明显增高,但与正常肛垫组织比较,不具备统计学意义;痔组织弹性纤维出现断裂、扭曲、变形、玻璃样变等异常,而正常肛垫组织中弹性纤维形态较规则、密集,断裂和变形少见。结论新生血管形成可能是痔的发病机制之一;MMP9对肛垫纤维支持结构的直接降解作用可能是痔形成和加重的一个重要机制;痔组织中iNOS表达增高还提示炎症因素和一氧化氮可能参与了痔的病理过程。     

沙门菌PCR检测技术应用进展

沙门菌是引起食物中毒的主要致病菌之一,其传统检测方法包括选择性培养、生化鉴定等步骤,耗时长、灵敏性差,很难满足快速检测要求。聚合酶链反应（PCR）技术是近年来广泛应用于食品中沙门菌快速检测的方法之一,其检测目的基因多种多样,主要包括属特异性引物基因、血清群特异性引物基因与血清型特异性引物基因。本文主要概述PCR技术应用于沙门菌检测的各种目的基因,并简要介绍常规PCR、多重PCR及实时定量PCR等技术的应用。     

Electrophysiologic Characteristics and Anatomical Complexities of Accessory Atrioventricular Pathways with Successful Ablation of Anterograde and Retrograde Conduction at Different Sites

RF Ablation of Accessory Pathways. Introduction: Catheter ablation may eliminate anterograde and retrograde accessory pathway conduction at closely adjacent but anatomically discrete sites. However, the mechanisms of this discrepancy, the electrophysiologic and anatomical characteristics, and information about systematic study from a large patient population are not available. The purpose of this study was to investigate the electrophysiologic characteristics and anatomical complexities of the accessory pathway in which anterograde and retrograde conduction was successfully ablated at different sites. Methods and Results: Thirty-eight (10.9%) patients (19 men and 19 women; mean age 37 ± 2.4 years) fulfilling the criteria of having separate ablation sites for anterograde and retrograde conduction were designated as group I, and the other 310 patients (215 men and 95 women; mean age 47 ± 0.6 years) were designated as group II. The patients with right-sided free-wall pathways had the highest incidence (18.6%) of separate ablation sites. The anatomical distance between anterograde and retrograde directions (left anterior oblique view. 13 ± 0.6 vs 8 ± 0.9 mm, P < 0.01; right anterior oblique view, 17 ± 0.6 vs 5 ± 0.7 mm, P < 0.01), and incidence of conduction impairment in one direction after successful ablation of another direction (15% vs 78%, P < 0.05) differed significantly between left and right free-wall pathways. The mean distances obtained from left (7 ±0.4 vs 14 ± 0.4 mm, P < 0.05) and right (7 ± 1.1 vs 15 ± 0.9 mm, P < 0.05) anterior oblique views were shorter in patients who had impairment of conduction properties than those in patients without impaired conduction after successful ablation of one direction. Conclusions: This study showed that anatomical and functional dissociation of the accessory pathway into anterograde and retrograde components was possible. Further study on the relation between electropbysiologic and pathologic characteristics would be helpful to confirm these findings.     

Montelukast decreased exhaled nitric oxide in children with perennial allergic rhinitis

BACKGROUND: Measurement of exhaled nitric oxide (eNO) is a simple and noninvasive method for assessment of inflammatory airway diseases. eNO is elevated in adolescent patients with perennial allergic rhinitis and related to bronchial hyperresponsiveness. The aim of this study was to investigate whether oral loratadine, montelukast, nasal budesonide or nasal sodium cromoglycate could reduce airway inflammation as indicated by decrease of eNO in children with perennial allergic rhinitis as demonstrated by eNO levels. METHODS: A randomized and investigator-blinded study was conducted in a hospital-based outpatient clinic. Children with perennial allergic rhinitis were divided into four groups and treated by loratadine, loratadine with nasal sodium cromoglycate, loratadine with oral montelukast, and loratadine with nasal budesonide, respectively. Allergic rhinitis scores, eNO and peak expiratory flow were measured before and 2, 4, 6 and 8 weeks after treatment. RESULTS: Results showed that eNO in children with perennial allergic rhinitis was reduced by nasal budesonide and oral montelukast within 2 weeks (24.56 +/- 14.42 vs 18.42 +/- 12.48, P < 0.001, in budesonide group; 27.81 +/- 13.4 vs 19.09 +/- 10.45, P < 0.001, in montelukast group), but not in the loratadine and cromoglycate groups. In contrast, loratadine or sodium cromoglycate also did not decrease eNO levels although they could decrease the symptom scores. CONCLUSIONS: It was concluded that four common treatment modalities could effectively release symptom scores, but decrease of airway inflammation as determined by decrease of eNO might be only achieved by nasal budesonide and montelukast, but not nasal sodium cromoglycate and loratadine. Children with perennial allergic rhinitis with high eNO levels may require oral montelukast or nasal budesonide treatment to prevent airway hyperresponsiveness.