Towards practical soft X-ray spectromicroscopy of biomaterials

Scanning transmission X-ray microscopy (STXM) is being developed as a new tool to study the surface chemical morphology and biointeractions of candidate biomaterials with emphasis on blood compatible polymers. STXM is a synchrotron based technique which provides quantitative chemical mapping at a spatial resolution of 50 nm. Chemical speciation is provided by the near edge X-ray absorption spectral (NEXAFS) signal. We show that STXM can detect proteins on soft X-ray transparent polymer thin films with monolayer sensitivity. Of great significance is the fact that measurements can be made in situ, i.e. in the presence of an overlayer of the protein solution. The strengths, limitations and future potential of STXM for studies of biomaterials are discussed.     

Evolutionary computing for knowledge discovery in medical diagnosis

One of the major challenges in medical domain is the extraction of comprehensible knowledge from medical diagnosis data. In this paper, a two-phase hybrid evolutionary classification technique is proposed to extract classification rules that can be used in clinical practice for better understanding and prevention of unwanted medical events. In the first phase, a hybrid evolutionary algorithm (EA) is utilized to confine the search space by evolving a pool of good candidate rules, e.g. genetic programming (GP) is applied to evolve nominal attributes for free structured rules and genetic algorithm (GA) is used to optimize the numeric attributes for concise classification rules without the need of discretization. These candidate rules are then used in the second phase to optimize the order and number of rules in the evolution for forming accurate and comprehensible rule sets. The proposed evolutionary classifier (EvoC) is validated upon hepatitis and breast cancer datasets obtained from the UCI machine-learning repository. Simulation results show that the evolutionary classifier produces comprehensible rules and good classification accuracy for the medical datasets. Results obtained from t-tests further justify its robustness and invariance to random partition of datasets.     

Identification of a new locus for autosomal dominant non-syndromic hearing impairment (DFNA7) in a large Norwegian family

Hereditary hearing impairment affects about 1 in 1000 newborns. In most cases hearing loss is non-syndromic with no other clinical features, while in other families deafness is associated with specific clinical abnormalities. Analysis of large families with non-syndromic and syndromic deafness have been used to identify genes or gene locations that cause hearing impairment. The present report describes a large Norwegian family with autosomal dominant non-syndromic, progressive high tone hearing loss with linkage to 1q21-q23. A maximum LOD score of 7.65 (theta = 0.00) was obtained with the microsatellite marker D1S196. Analysis of recombinant individuals maps the deafness gene (DFNA7) to a 22 cM region between D1S104 and D1S466. The region contains several attractive candidate genes. This report supports the idea of extensive genetic heterogeneity in hereditary hearing impairment and represents the first localization of a deafness gene in a Norwegian family.      

基于EGFR介导的信号通路探讨中药活性成分抗肿瘤研究进展

在我国恶性肿瘤已经成为最主要的死亡原因,近年来,恶性肿瘤发病率和死亡率逐年增高,严重威胁人民的生命健康,癌症负担不断增加。恶性肿瘤的治疗,目前主要是以手术为主的外科治疗、放射治疗和以细胞增殖抑制药物为代表的内科治疗,但有很多治疗局限性且治疗相关不良反应较大。而随着生物科学技术的发展,随着人们对肿瘤微环境、免疫学、细胞生物学和分子生物学等领域的研究,抗肿瘤治疗的热点已经转向高效低毒、目标明确的靶向治疗。表皮生长因子受体（EGFR）在细胞增殖、存活、分化、迁移、炎症和基质稳态等许多细胞过程中发挥着重要作用。EGFR通过多种方式促进肿瘤的生长、增殖及转移。中医药在恶性肿瘤的综合治疗中具有独特疗效,中药抗肿瘤具有多成分、多靶点、多途径的特点,能够发挥增效减毒、延长生命、提高生存质量的作用。目前发现的许多中药及其有效成分具有抗肿瘤作用,其机制与抑制EGFR信号传导通路有关。中药靶向抑制EGFR可以促进肿瘤细胞的凋亡和自噬,抑制肿瘤细胞的增殖和转移,延缓肿瘤的进展,是抑制肿瘤的潜在靶点。该文总结了EGFR信号传导通路和肿瘤发生发展的关系,并分析中药及其有效成分通过调节EGFR信号通路抗肿瘤的作用方...     

湖北省以替诺福韦为初治抗逆转录病毒方案的HIV/AIDS患者肾功能情况及其影响因素分析

目的 评估替诺福韦（tenofovir,TDF）作为一线治疗方案的HIV/AIDS患者慢性肾病（chronic kidney disease,CKD）发生情况及其影响因素。方法 采用回顾性队列研究方法,收集分析TDF组和齐多夫定（zidovudine,AZT）组HIV/AIDS的人口学信息及临床检查资料,比较2组患者CKD的发生率和差异,多因素Cox比例风险模型分析TDF组患者CKD发生的影响因素。结果 共纳入432例HIV/AIDS患者,其中TDF组249例,AZT组193例,开始治疗时年龄中位数分别为32（26,50）、31（26,43）岁,传播途径主要以同性传播为主（分别为69.48%、82.90%）。TDF组与AZT组24个月CKD累积发生率分别是2.8%和0,差异有统计学意义（P<0.05）。各时间点肾小球滤过率（eGFR）值中,AZT组均高于TDF组（均P<0.01）。多因素Cox比例风险模型分析显示：TDF组患者中,女性（HR=57.46,95% CI：2.981~67.684）和基线eGFR异常（HR=4.75,95% CI：1.351~16.702）者发生CKD的风险更高。结论 TDF可以引起HIV/AIDS患者CKD的发生,但发生率较低,女性和基线eGFR异常者发生CKD的风险更高。在临床治疗过程中,要密切关注女性患者以及评估患者肾功能。     

螺旋CT动态扫描对肝癌大血管侵犯的对比研究

目的 :进一步认识肝癌大血管侵犯的螺旋CT表现特征。方法 :75例肝癌伴大血管侵犯的病例中 ,2 6例前瞻性设计了动脉期同层面扫描加全肝门静脉期扫描的程序 ,选择兼顾病变及门静脉的靶平面 ,并与 31例双期扫描和 18例单纯门静脉期扫描的病例作对照。结果 :动脉期同层面扫描在动 静脉瘘和门静脉早显方面优于双期扫描 ,动脉期对显示大血管侵犯征象有特征性 ,癌栓在动脉期总强化率为 66 67% ( 38/ 5 7例 ) ,单纯门静脉期扫描不能显示动 静脉瘘和癌栓新生血管。结论 :动脉期同层面扫描能显示肿瘤和大血管侵犯引起的血流动力学异常 ,有助于定性和发现动 静脉瘘     

潜水人员防循方式与身心健康关系的研究

目的：了解海军潜水人员的防御方式特点和身心健康状况,并探讨二者的关系。方法：用防循方式问卷和康奈尔医学指数对海军某部177名潜水人员进行团体测验,用等级相关系数分析二者的相关关系。结果：潜水人员防循式与身心健康状况密切相关,不成熟防御方式和中间型防循式对身心健康的影响较大,身心健康问题较多者应用不成熟防御方式的频率较高,结论：防御方式对潜水人员身心健康可能有一定的影响。     

液中干燥法制备羟甲酰胺微囊及其缓释性研究

目的研究用液中干燥法制备的羟甲酰胺微囊的性质.方法正交实验设计优选制备工艺,光学显微镜观察其形态大小分布等,以体外溶出试验研究其缓释性.结果所得微囊粒径在100～800μm,载药量为53.8%,8h释放百分率为85%.结论液中干燥法制备的羟甲酰胺微囊有良好的开发应用前景.     

高胆汁酸血症对肝脏能量代谢的影响

目的：探讨高胆汁酸血症单一因素对肝脏能量代谢的影响。方法：经Wistar大鼠颈内静脉持续给阳外源性胆汁酸,升高其外周血清中胆汁酸浓度,模拟阻塞性黄疸患者外周血清中胆汁酸的变化规律。观察腹腕动脉酮体比值及肝组织能荷变化,时间一周。结果：随外周血清中胆法 酸浓度的升高,腹腔动脉血酮体比值,肝组织能荷均呈进行性下降,结论：高胆汁酸血症时肝脏能量代谢受损,表明在阻塞性黄疸患者肝功能损害中高胆汁酸血症起了重要作用。