“Smart” Materials for Biosensing Devices: Cell-Mimicking Supramolecular Assemblies and Colorimetric Detection of Pathogenic Agents

Mimicking cell membrane and the biomolecular recognition associated with membranes represents a great technical challenge, yet it has opened doors to innovative diagnostic and therapeutic methods. Our work has focused on design and synthesis of a class of smart materials exploiting biological principals for use in biosensors: these materials are functional polymeric assemblies that mimic the cell membrane and conveniently report the presence of pathogens with a color change. Biologically active cell membrane components are incorporated into conjugated polymers with desirable optical properties and the binding of the target molecules onto the material triggers conformational and electronic shifts that are reflected in a chromatic change (a so-called biochromic shift) that is conveniently observed and recorded. Langmuir–Blodgett thin films and vesicle bilayers provide ideal configurations for precise delivery of the biological binding entity to the sensing interface, and for control of molecular orientation for effective biomolecular interaction. Polydiacetylenic membrane-mimicking materials containing cell surface receptor gangliosides and sialic acid residues, respectively were formulated into these architectures and used for colorimetric detection of bacterial toxins and influenza virus. One advantage of these biochromic conjugated polymer (BCP) sensors is that their molecular recognition and signal transduction functionalities are resident in a single functional unit, making them amenable to convenient microfabrication and use.     

贫困大学生希望特质、应对方式与情绪的结构方程模型研究

目的:探讨贫困大学生的希望特质、应对方式对抑郁和幸福感的影响及其途径.方法:以369名贫困大学生为研究对象,采用成人希望特质量表.应对方式问卷,抑郁自评量表(SDS)和幸福感指数,用结构方程模型探讨希望特质和应对方式对情绪的影响途径.结果:希望特质对抑郁的影响符合不完全中介模型(x2/df=-1.862,GFI=0.980,CFI=0.985,RMSEA=0.048),希望特质对抑郁的直接影响占总影响的78.7％;希望特质对幸福感的影响符合完全中介模型(x2/df=2.101,GFI=0.976,CFI=0.979,RMSEA=0.055),以积极应对方式为中介的影响占总影响的89.3％.结论:希望特质是调节贫困大学生情绪的重要心理因素.希望特质对抑郁和幸福感的影响遵循不同的模式.     

The effect of an intercollegiate soccer game on maximal power performance.

The effect of a competitive soccer match on maximal power performance was assessed on 19 members of an NCAA Division III female soccer team. Performance testing occurred within 24 hours prior to the game (Pre), immediately postgame (IP), and 24 hours postgame (24P). Each subject performed a squat jump (SJ) and countermovement jump (CMJ). Comparisons between starters (n = 10) and nonstarters (n = 9) revealed no between-group differences in power performance at IP, but starters were found to have significantly lower power and force measures at 24P than nonstarters. There were significant correlations between playing time and peak force during the SJ at 24P (r = -0.47), and between playing time and peak power during the SJ at IP (r = -0.57) and 24P (r = -0.51), and during the CMJ at IP (r = -0.49). Comparisons between different positions revealed no differential fatigue patterns. Results of this study show that power performance appears to be maintained for the duration of a soccer match but declines significantly within 24 hours after the match. Position played does not appear to affect performance decrements seen at 24 hours postmatch.     

吻合器痔上黏膜环切术与传统外剥内扎术的对比研究

目的 探讨吻合器痔上黏膜环切术(procedure for proplapse and hemorrhoids,PPH)的适应证、方法、临床应用价值.方法 总结41例PPH手术(Ⅰ组)和62例传统外剥内扎术(Milligan-Morgan手术)(Ⅱ组)临床资料,对手术时间、术后止痛次数、住院时间、术后并发症及住院费用等进行对比研究.结果 总的症状改善满意率分别为95%(Ⅰ组)及82%(Ⅱ组),除住院费用外,Ⅰ组其手术时间、术后止痛次数、住院时间明显优于Ⅱ组,并发症发生率除术后便血、早期大便失禁、早期排尿困难外,余无统计学意义.结论 PPH治疗Ⅲ°～Ⅳ°痔的近期疗效优于Milligan-Morgan手术,且具有安全、有效、手术时间短、住院时间少、恢复快等优点.     

人肿瘤细胞与正常细胞内微管的PAP免疫酶细胞化学观察

我们利用兔抗微管蛋白抗体和兔抗辣根过氧化物酶(HRP)抗血清制备的HRP—抗HRP(PAP)复合物,建立了微管的PAP免疫酶细胞化学方法。应用此法观察到人食管癌ECa 109、胃癌SGC 7901,乳腺癌MCF 7和成骨肉瘤OS 732细胞间期胞质微管减少或消失,只有大量弥散分布的微管蛋白棕色反应产物,在微管组织中心(MTOC)附近十分密集,而正常成纤维细胞和胎儿胃粘膜上皮细胞间期,都有发达的胞质微管结构(CMTC)。在分裂期,这些肿瘤细胞都显示纺锤体微管,与正常细胞比较无明显差异。本研究应用PAP方法进一步证明,以前用免疫荧光细胞化学方法观察到的人肿瘤细胞间期胞质微管缺陷的特征。除去低温(4℃)或秋水仙酰胺处理后,解聚的CMTC又可恢复,表明本方法与免疫荧光染色法,同样具有很高的特异性。本工作在细胞固定及免疫反应的某些步骤上有所改进。     

Detection and deletion of motion artifacts in electrogastrogram using feature analysis and neural networks

Electrogastrogram is a surface measurement of gastric myoelectrical activity, and electrogastrography has been an attractive method for physiological and pathophysiological studies of the stomach due to its nonivasive nature. Motion artifacts, however, ruin the electrogastrogram (EGG), and make the analysis very difficult and sometimes even impossible. They must be eliminated from EGG signals before analysis. Up to now, this can only be done by visual inspection, which is not only time-consuming but also subjective. In this study, a method using feature analysis and neural networks has been developed to realize automatic detection and elimination of the motion artifacts in EGG recordings by computer. Experiments were conducted to investigate the characteristics of different motion artifacts. Useful features were extracted, and different combinations of the features used as the input of the neural network were compared to obtain the optimal performance for the detection of motion artifacts using the artificial neural network.     

Nucleolar localization of non-structural protein 3b, a protein specifically encoded by the severe acute respiratory syndrome coronavirus

The open reading frame 3 (ORF3) of the severe acute respiratory syndrome coronavirus (SARS-CoV) genome encodes a predicted 154-amino acid protein, which lacks similarities to any known protein, and is named 3b. In this study, it was shown that 3b protein was predominately localized to nucleus with EGFP tag at its N- or C-terminus. The localization patterns were similar in different transfected cells. Immuno-fluorescence assay revealed that 3b protein was co-localized well with C23 in nucleolus. C23, B23 and fibrillarin all are important nucleolar proteins, which localize in the region of the nucleolus. Co-transfection of p3b-EGFP with pC23-DsRed, pB23-DsRed and pfibrillarin-DsRed further confirmed 3b's nucleolus localization. With construction of serial truncated mutants of 3b, a region (residues 134-154 aa) responsible for nucleolar localization was determinated in 3b protein. These results provide a new insight for further functional studies of SARS-CoV 3b protein.     

30例麻疹暴发疫情的调查分析

目的调查本地某乡镇一次麻疹疫情的流行强度,描述其三间分布,分析暴发原因及影响因素。方法现场流行病学调查,酶联免疫捕获法检测麻疹IgM抗体,作免疫空白与麻疹发病关联的病例对照研究。结果2006年5月～7月,该乡镇发生30例麻疹局部暴发,其中29例儿童麻疹,1例成人麻疹,5例麻疹IgM抗体阳性。发病地点主要为小学和和幼儿园,罹患率分别为7.94%、7.87%。免疫空白与发病关系研究表明,初种免疫空白OR=7.2,X2=6.84,复种免疫空白OR=11.0,X2=9.48;影响免疫空白形成的社会因素调查,未接受麻疹疫苗初种或复种儿童的父母双亲常年在外务工占82.4%(28/34),有麻疹疫苗接种史儿童的父母常年在外务工占35.3%(12/34),二者有统计学差异(X2=15.54)。结论免疫空白是麻疹暴发形成的重要因素,农村儿童的父母常年在外务工形成隔代抚养教育对计免工作有负面影响。     

中晚期重型乙型肝炎血浆置换与内科治疗生存率的比较

观察血浆置换、内科治疗对中晚期重型乙型病毒性肝炎生存率的影响,探索中晚期重型肝炎的治疗方法。方法观察在内科治疗基础上给予血浆置换患者的肝功能、并发症及疾病的转归,与同期仅予内科综合治疗的患者相比较,对相应的临床资料进行统计学分析,从而了解两种治疗方法的疗效。结果血浆置换组36例,18例好转、18例死亡,内科治疗组32例,13例好转、19例死亡,两组之间患者生存情况无统计学差异;肝功能指标(ALT、AST、SB、ALB、TC、ChE和凝血酶原时间(PT)也无统计学差异。结论与内科治疗相比较,在其基础上给予血浆置换并不能提高中晚期重型病毒性肝炎生存率;中晚期重型肝炎患者的预后决定于其肝功能衰竭的程度。