乙酸溶解-酶消化法制备医用胶原膜

目的:探讨I型胶原的提取和胶原膜的制备方法。方法：取新鲜成年牛跟腱，用乙酸溶解-酶消化法提取I型胶原，并进行盐析、透析、纯化得到精制的液态胶原，用戊二醛进行交联。结果：提取的胶原紫外分光光谱最高吸收峰值为230 nm左右；聚丙酰胺凝胶电泳呈现2条相邻带(相对分子质量98 000左右)，符合I型胶原的特性。冻干交联胶原膜呈白色海绵状，具有一定弹性。扫描电镜观察胶原膜为孔网状结构，孔径15～50 μm。 结论：乙酸溶解-酶消化法提取牛腱胶原是一种简单、理想的方法，可得到含量及纯度较高的Ι型胶原。     

子宫颈腺癌组织中癌胚抗原和甲胎蛋白的检测

采用免疫金银染色技术,对64例子宫颈腺癌组织进行了癌胚抗原(CEA)和甲胎蛋白(AFP)的免疫组化检测.结果表明,CEA和AFP的阳性率分别为75.00%和14.06%.不同分化程度组织间,CEA阳性率无显著性差异(P>0.05),但在不同组织学类型间,CEA阳性率差异有显著性意义(P<0.05).提示对子宫颈腺癌组织进行CEA检验,有助于其组织学分类.     

Changes in the prevalence and severity of recurrent wheezing in infants: The results of two surveys administered 7 years apart

Objective:To identify changes in the prevalence and severity of recurrent wheezing (RW) in infants using data obtained from two surveys administered seven years apart. Methods: A cross-sectional, international, population-based study in infants aged 12–15 months was conducted. Data were obtained from two surveys (S1 and S2, in 2005 and 2012, respectively) using the same methodology in three large Latin American cities: Curitiba (Brazil), São Paulo (Brazil), and Santiago (Chile). Results: A decrease in the overall prevalence of RW was identified between S1 (23.3%) and S2 (20.4%), p = 0.004, but it was mainly driven by the reduction observed in São Paulo; in Curitiba and Santiago, this change was not significant. The mean prevalence of the following RW severity indicators remained high and stable: severe wheezing episodes (56.9% in S1 and 54.2% in S2, p = 0.32) and emergency department (ED) visits for wheezing (S1 = 68.1%, S2 70.9%, p = 0.21). A significant increase in admissions for wheezing (21.1% to 26.7%, p = 0.004) was observed. In Curitiba and São Paulo, there were significant increases in the prevalence of physician-diagnosed asthma and in the use of inhaled corticosteroids and oral antileukotrienes. Conclusions: The prevalence and severity of RW during the first year of life remained high over time, with remarkably high rates of ED visits, admissions for wheezing and use of asthma medications. This study suggests the need for considering early asthma diagnosis and to establish an appropriate treatment in infants with recurrent and severe asthma-like symptoms.     

DNA Duplexes with Hydrophobic Modifications Inhibit Fusion between HIV-1 and Cell Membranes

Discovery of new drugs for the treatment of AIDS typically possessing unique structures associated with novel mechanisms of action has been of great importance due to the quick drug-resistant mutations of HIV-1 strains. The work presented in this report describes a novel class of DNA duplex-based HIV-1 fusion inhibitors. Hydrophobic groups were introduced into a DNA duplex skeleton either at one end, at both ends, or in the middle. These modified DNA duplexes inhibited fusion between HIV-1 and human cell membranes at micro- or submicromolar concentrations. Respective inhibitors adopted an aptamer pattern instead of a base-pairing interaction pattern. Structure-activity relationship studies of the respective DNA duplexes showed that the rigid and negatively charged DNA skeletons, in addition to the presence of hydrophobic groups, were crucial to the anti-HIV-1 activity of these compounds. A fluorescent resonance energy transfer (FRET)-based inhibitory assay showed that these duplex inhibitors interacted with the primary pocket in the gp41 N-terminal heptad repeat (NHR) instead of interacting with the lipid bilayers.     

The changing face of sympathetic overactivity in hypertension

Background. The precise pathophysiological processes underlying the prothrombotic or hypercoagulable state in atrial fibrillation (AF) remain uncertain. We hypothesized a relationship between abnormal endothelial damage/dysfunction, coagulation, and angiogenic factors, thereby contributing to increased thrombogenicity.

Methods. Plasma levels of von Willebrand factor (vWF, an index of endothelial damage/dysfunction) and tissue factor (TF, an index of coagulation), as well as the angiogenic factors, vascular endothelial growth factor (VEGF), angiopoietin‐1 (Ang‐1) and angiopoietin‐2 (Ang‐2), were measured by enzyme‐linked immunosorbant assay (ELISA) in 59 chronic AF patients. Data were compared to 40 age‐ and sex‐matched healthy controls in sinus rhythm.

Results. Plasma vWF, VEGF and Ang‐2 were significantly higher in AF patients compared to healthy controls (P = 0.005, P = 0.0055 and P<0.0001 respectively) but there were no significant differences in plasma Ang‐1 or TF levels between the two groups (P = 0.925 and P = 0.121 respectively). Significant correlations were found between VEGF and vWF levels (Spearman, r = 0.262, P = 0.011) and between VEGF and Ang‐2 (r = 0.333, P = 0.001).

Conclusions. Raised VEGF in association with Ang‐2 and vWF may reflect a link between abnormal endothelial damage/dysfunction and angiogenic factors. These may act together to alter TF expression and endothelial integrity, thereby contributing to the prothrombotic state in AF.     

新型颈椎前路经椎弓根固定钉板系统的研制及生物力学分析

背景:临床中为了解决颈椎翻修/骨质疏松/长节段固定等问题,一般选择进行前、后路联合内固定来获得满意的术后稳定性,难免加重患者的手术创伤,增加术后并发症概率及住院费用.而颈前路反向椎弓根内固定可通过一次前路手术获得前后路联合内固定的稳定性,但临床缺少适用的颈前路椎弓根内固定系统.目的:依据颈椎相关解剖结构研制出新型颈椎前...