Evolution of a Wavelike Undulation in Polymer Thin Films with Immobilized Film Spanning Nanoparticles

The evolution of wavelike surface undulations in a thin polymer film under thermal stress in the presence of immobilized film spanning nanoparticles (NPs) is investigated. The elastic stresses in the plane of the polymer thin films is induced by fixed lateral constraints within the film (immobilized NPs) that resist in‐plane film thermal expansion as the temperature increases. Wavelike surface undulations arising from stress relaxation are observed as the thin‐film systems are heated above the glass‐transition temperature (T_g). The thermal stress affects both the characteristic wavelengths and the amplitudes of the wavelike surface undulations. Although the origin is different, the dynamic evolution of these wavelike undulations is strikingly similar in characteristics to spinodal decomposition. As compared with typical spinodal‐decomposition kinetics in liquid systems in which the early and intermediate stages are difficult to probe due to the narrow range of time scales, the overall evolutionary process of the wavelike surface undulations in NP‐filled polymer thin films is captured. The growth of the wavelike undulations shows characteristic time dependencies at the intermediate and late stages of instability.

     

体外循环和非体外循环下冠状动脉旁路移植术中 患者脑氧饱和度的变化趋势分析

目的 探讨体外循环和非体外循环下冠状动脉旁路移植术中患者脑氧饱和度（rScO2）的变化趋势。 方法 前瞻性选取2018 年2 月—2019 年6 月在上海市第一人民医院择期行冠状动脉旁路移植术的105 例患 者。其中,56 例接受非体外循环冠状动脉旁路移植术（OPCAB）,49 例患者接受体外循环冠状动脉旁路移植 术（CCABG）。术中分别选择T0 ～ T9 10 个时间点检测rScO2,另外记录术后7 d 内术后认知功能障碍（POCD） 发生率。结果 CCABG 组患者手术时间长于OPCAB 组（P <0.05）,术中最低鼻咽温和红细胞比容（HCT） 低于OPCAB 组（P <0.05）,术中最高血糖（Glu）和血乳酸（Lac）高于OPCAB 组（P <0.05）;但是两组术 中最低rScO2 比较,差异无统计学意义（P >0.05）。两组rScO2 在不同时间、组间、变化趋势上有差别（P <0.05）。 CCABG 组rScO2 与鼻咽温、Lac 呈正相关（r =0.229 和0.283,P =0.005 和0.002）,而OPCAB 组rScO2 只 与Lac 呈正相关（r =0.214,P =0.010）。OPCAB 组和CCABG 组POCD 发生率分别为39.29%（22/56）和 32.65%（16/49）,且CCABG 组POCD 患者最低rScO2 低于非POCD 患者（P <0.05）。结论 虽然OPCAB 与CCABG 术中患者rScO2 变化趋势有差异,但是rScO2 可能不是影响术后早期POCD 发生的主要原因。     

体位固定方式和BMI对胸部肿瘤放疗摆位误差的影响

目的探讨胸部肿瘤患者接受放疗时,体位固定方式和身体质量指数(Body Mass Index,BMI)对摆位误差的影响。方法回顾性分析接受调强放疗的132例胸部肿瘤患者的临床资料。根据放疗时患者双手摆放位置的不同分为A、B两组,A组患者(82例)双手十指交叉置于专用臂托上,B组患者(50例)双手置于身体两侧。根据患者的BMI分为1组(偏瘦)、2组(正常)和3组(超重)。首次治疗前行CBCT扫描,使用自动骨性配准结合手动微调,计算出x、y和z轴方向的摆位误差。比较不同体位固定方式和不同BMI的摆位差异。结果B组患者x方向摆位误差小于A组(P<0.05);B3组患者x方向摆位误差小于A3组(P<0.05)。在y和z方向上,A组和B组之间的差异均无统计学意义(P>0.05)。结论胸部肿瘤患者放疗时,患者双手摆放位置对摆位误差有影响,采用双手体侧位固定方式引起的摆位误差较小。患者BMI越大,摆位误差差异越明显,超重患者更宜选用双手体侧位固定方式。     

再谈2019中国乙型肝炎母婴传播防治指南:证据,证据,还是证据

乙型肝炎病毒(HBV)母婴传播是导致慢性HBV感染的主要原因,因此如何阻断HBV母婴传播,实现HBV阳性母亲所生新生儿HBV“零感染”的目标一直是临床研究的热点问题,国际和我国的乙型肝炎防治指南中都重点讨论这个问题,也发表了相关共识。由中华医学会感染病学分会和GRADE中国中心制定的《中国乙型肝炎病毒母婴传播防治指南(2019年版)》(以下简称《指南》),并在《中华传染病杂志》发表.     

葡聚糖包裹的超顺磁性Fe3O4纳米颗粒用于MRI造影剂的研究

目的探讨葡聚糖包裹的超顺磁性Fe3O4纳米颗粒（dextran-coated superparamagnetic iron oxides nanoparticles,dextran／SPIONP）作为间质注射的MRI造影剂的可行性。方法应用界面共沉淀法,制备dex—tran／SPIONP,用透射电镜、能谱分析、X射线衍射、红外光谱测试、热重分析等方法对dextran／SPIONP的大小、磁性能等进行表征,并研究葡聚糖对SHONP的影响。然后,将dextran／SPIONP稀释成不同剂量,兔舌粘膜下间质注射后的不同时间段,切取前哨淋巴结,行核磁共振波谱分析,确定dextrart／SPIONP的最适剂量和最佳检测时间。结果dextran／SPIONP的平均直径为6～9nm,其表征与经典的共沉淀法制备的颗粒一致,具有超顺磁性,葡聚糖是影响SPIONP饱和磁化强度的主要因素。dextran／SPIONP用于间质注射的最适剂量为含铁量20μmol,最佳检测时间为注射后2Ah。结论用界面共沉淀法制备的dextran／SPIONP是一种适用于间质注射的MRI造影剂。     

Chronic inflammatory demyelinating polyneuropathy mimicking diabetic neuropathy in a young female with type 2 diabetes mellitus

The presentations of chronic inflammatory demyelinating polyneuropathy (CIDP) overlap with those of diabetic peripheral neuropathy (DPN). We described a young girl with CIDP underlying type 2 diabetes mellitus, presenting with progressive numbness and limb weakness, who was initially misdiagnosed to have DPN. Finally immunosuppressive therapy got good response.     

Polymorphisms in XPC provide prognostic information in acute myeloid leukemia

Acute myeloid leukemia (AML) is the most common type of adult leukemia for which cytosine arabinoside-based chemotherapy is the main treatment. Single nucleotide polymorphisms within the nucleotide excision repair pathway may alter the susceptibility of leukemia cells to chemotherapy. We investigated the roles of six single nucleotide polymorphisms (ERCC5rs76871136, ERCC5rs77569659, ERCC5rs873601, XPCrs2228000, XPCrs2228001, and XPCrs1870134) in the nucleotide excision repair pathway in influencing the outcome of patients with AML treated with cytosine arabinoside-based chemotherapy. One hundred fifty-one patients with AML in a Chinese population were enrolled in this study. Genotypes were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. We found that the distribution of three genotypes of XPCrs1870134 significantly differed in the cytogenetic risk groups (P?=?0.04). A statistically significant correlation between polymorphisms of XPCrs2228001 and gender was found among the gender groups (P?=?0.03). Moreover, patients carrying at least one variant allele (XPCrs2228001AA+CC) were more likely to respond better than those who did not carry a variant. However, no significant association was detected between polymorphisms in ERCC5 and treatment response. These findings suggest that XPC polymorphisms are important markers for the outcome of patients with AML in the Chinese population.     

聚乙二醇干扰素α-2a联合阿德福韦酯对HBeAg阳性慢性乙型肝炎的治疗

目的:分析聚乙二醇干扰素-2a(peginterferon-2a,Peg-IFN-2a)治疗HBeAg阳性慢性乙型肝炎应答不佳者联合阿德福韦酯(adefovirdipivoxil,ADV)治疗48 wk的疗效、安全性,并评价48 wk疗效预测指标.方法:140例患者初始均接受Peg-IFN-2a每周1次皮下注射单药治疗,根据24 wk时HBVDNA水平进行分组.A组90例患者治疗24 wk时HBV DNA≥2.0×103IU/mL且HBV DNA下降≥2 log10 IU/mL,其中A1组45例患者加用ADV治疗至48 wk,A2组45例患者继续Peg-IFN-2a单药治疗至48 wk;B组50例患者治疗24 wk时HBV DNA<2.0×103IU/mL,继续Peg-IFN-2a治疗至48 wk.比较各组基线及治疗中HBV DNA、HBsAg、HBeAg及ALT水平.结果:治疗36、48 wk时HBV DNA转阴率B组>A1组>A2组(P<0.01).治疗36 wk时HBV DNA下降值B组>A1组>A2组(P<0.01).48 wk时HBV DNA下降值A1组>A2组(P<0.01),A1、B组之间差异无统计学意义.治疗24-48 wk期间,A1组HBeAg血清转换率升高幅度>A2组和B组(P<0.01).治疗48 wk时HBsAg下降A1组4例、A2组1例、B组2例.治疗36、48 wk时A1与A2、B组ALT复常率差异无统计学意义.A1组治疗48 wk时HBV DNA阴转与治疗36 wk HBVDNA下降值有关.治疗36 wk时HBV DNA较基线下降值对48 wk时HBV DNA阴转的阳性预测值为90.5%,较24 wk时下降值对48 wk时HBV DNA阴转的阳性预测值为95.7%.结论:Peg-IFN-2a治疗HBeAg阳性慢性乙型肝炎应答不佳者联合ADV治疗提高病毒应答、HBeAg血清转换率,其中治疗36 wk时HBV DNA下降值可预测48 wk疗效.