腺病毒介导noggin基因修饰神经干细胞

目的:以重组腺病毒介导的noggin基因修饰小鼠海马源性神经干细胞,为基因修饰的神经干细胞移植治疗中枢神经系统疾病提供依据。方法:以重组腺病毒介导的noggin基因转染体外培养的神经干细胞,MTT法检测转染前、后神经干细胞的生长活性,应用免疫细胞化学及Western blot检测转染后Noggin蛋白在神经干细胞中的表达及noggin基因对神经干细胞定向分化的影响。结果:重组腺病毒pAdEasy-1-noggin转染神经干细胞后,神经干细胞中Noggin蛋白表达持续增加;转染后的NSCs在含血清的培养液中能定向分化为神经元、星形胶质细胞和少突胶质细胞,并且其分化为神经元的数量明显增加。结论:重组腺病毒介导的noggin基因在细胞中可持续稳定表达,noggin基因能够促进神经干细胞定向分化为神经元,抑制其向星形胶质细胞方向分化,为下一步进行神经干细胞体内移植治疗提供了实验依据。     

地面传热实验的微重力修正模拟

目的 使空间飞行器地面传热实验的结果能够有效地应用到空间微重力条件下。方法 用数值模拟的方法研究了矩形空间内45度对称间隔斜进风以及垂直进风和换热情况,壁面条件为等壁温或等热流。对重力和微重力两种情况进行了对比。结果 对等壁温情况,提出了表征空间飞行器舱内换热的关系式,并且将数值计算所得数据按这些关系式进行了最小二乘拟合,得到了空间微重力工况和地面工况下的换热关系式。对等热流情况,本文列出了重力和微重力条件下的最高壁面温度值,给出了两种情况时最高壁面温度的拟合公式。结论 根据本文的内容,可以对地面模型装置的实验结果进行修正,得到空间飞行器原型内的换热情况。     

Full thickness open tear of the tendoachilles - Functional outcomes following a stable,single stage repair

ObjectiveOpen injuries of the Tendoachilles present a challenge to the treating surgeon. Although, common in our setting, there is a paucity of literature regarding management of the same. The purpose of this retrospective study was to analyse the functional outcomes following debridement and primary repair of open tears of the Tendoachilles.Materials and methodsPatients with open tears of the tendoachilles, between January 2012 to January 2017. After obtaining demographic data, including mechanism of injury, all patients were managed by adequate debridement and primary repair, by Pennington’s modification of Kessler’s technique in a single sitting, paratenon closed circumferentially, plantaris reinforcement used when end to end repair couldn’t be achieved. Below knee cast for 2 months. Weight bearing started at three months. Statistical analysis using paired t-test for calf circumference, ankle range of motion comparing with uninjured limb. Functional outcome assessment by AOFAS hindfoot score and Achilles tendon rupture score.Results23 male patients, mean age 35, were analysed. Field injury was the most common mechanism, with slip in Indian lavatory pans accounting for four patients. Average time to surgery from injury was 22 hours. Plantaris reinforcement in one case. No case of wound dehiscence, scar adherence, tendon rerupture or infection. One patient had serous discharge at three weeks which settled with oral antibiotics. 21 patients performed single heel raise. There was no significant difference in calf circumference and ankle range of motion compared to uninjured limb. Mean AOFAS score was 92, mean Achilles tendon rupture score 77.ConclusionThough open injuries of the tendoachilles is fraught with complications, early debridement, adequate repair of the tendon edges with circumferential closure of the paratenon, yields adequate functional outcomes with minimal complications.     

蛋白质芯片技术及其在全基因组翻译后修饰分析中的应用

蛋白质芯片技术可用于研究蛋白质-DNA、蛋白质-配基和蛋白质与蛋白质之间的相互作用,是当前生物科学研究中的重要内容。近年来,运用蛋白质芯片技术对全基因组进行生物化学分析的应用取得令人瞩目的成就。现着重总结蛋白质芯片技术及其在全基因组翻译后修饰分析中的应用。     

疟原虫表观遗传学研究进展

疟原虫的生活史包括配子体、裂殖子、环状体等多个阶段,先后寄生在多种类型的宿主细胞才完成完整的生命周期。在这些生活史中的不同虫期,疟原虫表现出明显的表型差异;在应对生存环境的改变时,其基因表达能够很精确地做出应对。近年来诸多研究表明,无论是这些生命阶段的转换,还是对宿主的适应,疟原虫表观遗传学方面的调控都起了很大的作用。对疟原虫表观遗传学的研究,有利于深入了解疟原虫与宿主的相互作用机制,对防治疟疾工作具有重要意义。本文从组蛋白修饰、DNA甲基化、非编码RNA编辑等方面介绍目前疟原虫表观遗传学研究进展。     

表观遗传修饰在神经退行性变性疾病中的作用研究进展

表观遗传修饰对神经发育、神经干细胞命运决定和神经系统的生理功能发挥具有重要的调节作用。异常的表观遗传修饰与阿尔茨海默病、帕金森病和亨廷顿病等神经退行性变性疾病的发生和发展有密切关系：异常升高的DNA甲基化修饰抑制了一些修复基因的表达,影响亨廷顿病进展;阿尔茨海默病患者大脑中H3K27ac和H3K9ac组蛋白修饰增加,影响神经变性;RNA甲基化修饰在阿尔茨海默病和帕金森病两种疾病动物模型中呈现差异化的改变。因此,表观遗传修饰可能作为神经系统疾病的潜在治疗靶点。本文综述了表观遗传修饰参与神经退行性变性疾病及其分子机制的最新研究进展。     

PLAT铸造陶瓷修复体表面着色中颜色改正的研究

铸造陶瓷的表面着色是一个依赖技术的过程。本研究通过对经黄色、橙色着色剂着色后的铸造陶瓷盘应用薄层同色着色剂及红、绿、蓝、紫色着色剂后的色度测量,发现同色着色剂的应用使饱和度增加;红色、绿色可使其色相偏红、偏绿;蓝色、紫色可有效地降低饱和度,但使色相有不同程度地偏绿偏红。     

EAA-g-MPEG的合成及其对HDPE的亲水改性

以乙烯-丙烯酸（EAA）共聚物及聚乙二醇单甲醚（MPEG）为主要原料,通过酯化反应制备了一系列接枝共聚物EAA-g-MPEG,并将其与高密度聚乙烯（HDPE）共混制得改性薄膜。研究了反应条件对接枝反应的影响,通过FT-IR、TG、DSC等方法研究了接枝产物的结构及其热性能。结果表明,随着侧链MPEG分子量的提高,产物接枝率逐渐下降;随接枝率的提高及侧链长度的增长,产物热稳定性下降;随接枝率的提高,产物的结晶熔融峰向高温方向移动,结晶性变好;EAA-g-MPEG可有效改善HDPE的表面亲水性能,当其质量分数为10%时,可使改性HDPE薄膜的水接触角由105°降至59°。     

Effect of Surface Modification for Carbon Cathode Materials on Charge–Discharge Performance of Li-Air Batteries

Li-air batteries have attracted considerable attention as rechargeable secondary batteries with a high theoretical energy density of 11,400 kWh/g. However, the commercial application of Li-air batteries is hindered by issues such as low energy efficiency and a short lifetime (cycle numbers). To overcome these issues, it is important to select appropriate cathode materials that facilitate high battery performance. Carbon materials are expected to be ideal materials for cathodes due to their high electrical conductivity and porosity. The physicochemical properties of carbon materials are known to affect the performance of Li-air batteries because the redox reaction of oxygen, which is an important reaction for determining the performance of Li-air batteries, occurs on the carbon materials. In this study, we evaluated the effect of the surface modification of carbon cathode materials on the charge–discharge performance of Li-air batteries using commercial Ketjenblack (KB) and KB subjected to vacuum ultraviolet (VUV) irradiation as cathodes. The surface wettability of KB changed from hydrophobic to hydrophilic as a result of the VUV irradiation. The ratio of COOH and OH groups on the KB surface increased after VUV irradiation. Raman spectra demonstrated that no structural change in the KB before and after VUV irradiation was observed. The charge and discharge capacities of a Li-air battery using VUV-irradiated KB as the cathode decreased compared to original KB, whereas the cycling performance of the Li-air battery improved considerably. The sizes and shapes of the discharge products formed on the cathodes changed considerably due to the VUV irradiation. The difference in the cycling performance of the Li-air battery was discussed from the viewpoint of the chemical properties of KB and VUV-irradiated KB.     

Antibacterial and Biodegradable Polysaccharide-Based Films for Food Packaging Applications: Comparative Study

One of the major objectives of food industry is to develop low-cost biodegradable food packaging films with optimal physicochemical properties, allowing for their large-scale production and providing a variety of applications. To meet the expectations of food industry, we have fabricated a series of solution-cast films based on common biodegradable polysaccharides (starch, chitosan and alginate) to be used in food packaging applications. Selected biopolymers were modified by the addition of glycerol and oxidized sucrose (starch), glycerol (chitosan), and glycerol and calcium chloride (alginate), as well as being used to form blends (starch/chitosan and starch/alginate, respectively). A chestnut extract was used to provide antibacterial properties to the preformed materials. The results of our studies showed that each modification reduced the hydrophilic nature of the polymers, making them more suitable for food packaging applications. In addition, all films exhibited much higher barrier properties to oxygen and carbon dioxide than commercially available films, such as polylactic acid, as well as exhibiting antimicrobial properties against model Gram-negative and Gram-positive bacteria (Escherichia coli and Staphylococcus epidermidis, respectively), as well as yeast (Candida albicans).