Relationship Between Architecture and Adhesion in Polyurethane‐Based Copolymers, 2

Summary: This study describes the chain extension, with polycaprolactone diols, of polyurethane‐graft‐poly(butyl acrylate)s which were first prepared by the step growth polymerization of a mixture of diphenylmethane‐4,4′‐diisocyanate (MDI) and α,α′‐dihydroxyl‐poly(butyl acrylate)s. The success of the chain extension reaction was studied and confirmed by ¹H NMR, SEC and DSC analysis. The incorporation of polycaprolactone sequences in the polyurethane chains modified their specific adhesive properties, bringing cohesion to the material, as demonstrated by tack measurements.

PUR‐graft‐PBA extended with PCL.     

血管紧张素原基因的六种单核苷酸多态与原发性高血压的相关性

目的　研究血管紧张素原 (angiotensinogen,AGT)基因 6个位点的单核苷酸多态及其构成的单倍型与中国汉族人原发性高血压的相关性。方法　采用多重SNa Pshot反应 ,在 185例原发性高血压患者和185名健康对照者中 ,对 AGT基因启动子区域的 G- 2 17A、G- 15 2 A、A- 2 0 C、G- 6 A及第 2外显子的T174 M和 M2 35 T多态进行基因分型。结果　 6种单核苷酸多态的基因型分布及其等位基因频率在原发性高血压组和对照组中差异无显著性 (P>0 .0 5 )。单倍型分析提示由 - 15 2 A,- 2 0 C,- 6 A和 2 35 T等位基因构成的 H4单倍型在原发性高血压组中明显增加 ,与对照组相比差异有显著性 (P<0 .0 5 )。结论　AGT基因G- 15 2 A,A- 2 0 C,G- 6 A和 M2 35 T多态可能对中国汉族人原发性高血压的发病起了重要作用。     

CⅡTA M1-RNA对MHCⅡ类分子表达的抑制作用

目的探讨MHCⅡ类分子转录激活因子（CⅡTA）的M1-RNA对细胞表面MHCⅡ类分子表达的抑制。方法M1-RNA是核糖核酸酶P的催化活性单位，设计并克隆针对CⅡTA第452、629位点的M1-RNA（分别为M1-452-GS、M1-629-GS）及其相应的CⅡTA靶基因，分别插入pUC19、pGEM-7zf（＋）载体，进行细胞外切割活性筛选。将细胞外切割作甩明显的M1-629-GS亚克隆入psNAV载体（psNAV-M1-629-GS，pA629）并稳定转染ECV304细胞株，流式细胞术检测经典的MHCⅡ（HLA-DR、-DP、-DQ）类抗原表达，RT-PCR检测CⅡTA的mRNA水平。结果pA629阳性ECV304细胞株与对照组比较，HLA-DR、-DP抗原表达分别降低了89．21％及92．31％；同时CⅡTA的mRNA含量降低（P〈0．05）。结论CⅡTA的M1-RNA（M1-629-GS）降低了自身mRNA含量，从而阻止其调控的MHCⅡ类分子的表达。     

Phenotype delineation of ZNF462 related syndrome

Zinc finger protein 462 (ZNF462) is a relatively newly discovered vertebrate specific protein with known critical roles in embryonic development in animal models. Two case reports and a case series study have described the phenotype of 10 individuals with ZNF462 loss of function variants. Herein, we present 14 new individuals with loss of function variants to the previous studies to delineate the syndrome of loss of function in ZNF462. Collectively, these 24 individuals present with recurring phenotypes that define a multiple congenital anomaly syndrome. Most have some form of developmental delay (79%) and a minority has autism spectrum disorder (33%). Characteristic facial features include ptosis (83%), down slanting palpebral fissures (58%), exaggerated Cupid's bow/wide philtrum (54%), and arched eyebrows (50%). Metopic ridging or craniosynostosis was found in a third of study participants and feeding problems in half. Other phenotype characteristics include dysgenesis of the corpus callosum in 25% of individuals, hypotonia in half, and structural heart defects in 21%. Using facial analysis technology, a computer algorithm applying deep learning was able to accurately differentiate individuals with ZNF462 loss of function variants from individuals with Noonan syndrome and healthy controls. In summary, we describe a multiple congenital anomaly syndrome associated with haploinsufficiency of ZNF462 that has distinct clinical characteristics and facial features.     

戊型肝炎病毒归科的形态学证据

采用超簿切片制样及负染色免疫电镜方法，对经细胞培养自戊型肝炎病人分离的８７Ａ株病毒进行了形态及形态发生的研究。结果显示，感染细胞胞浆局灶性空泡液泡病变区明显而普遍；病毒呈晶格样排列，在胞浆内装配成熟，与粗面内质网、病毒性包涵体、微丝等密切相关；病毒毒粒无囊膜，大小约３０ｎｍ呈圆形，表面形态不规整，电致密度不均一，偶见“凹杯形”、“刺突”等表面超微结构；感染细胞核呈现扭曲变形，异染色质趋边等显著受累及病变。其形态及形态发生特征表明其应为嵌杯病毒科新属—嗜肝ＲＮＡ病毒属的成员，而部分核苷酸序列分析也支持其为戊型肝炎病毒。     

促肝细胞生长素诱导人肝癌细胞（BEL－7402）凋亡

本文从细胞学、ＤＮＡ凝胶电泳、流式细胞术三方面研究促肝细胞生长素（ｐＨＧＦ）在体外对肝癌细胞增殖活性的影响。结果表明：ｐＨＧＦ对肝癌ＢＥＬ－７４０２细胞增殖有抑制作用，并存在剂量和时间相关性。其４８ｈ的半数抑制浓度（ＩＤ５０）为０．３７ｍｇ／ｍｌ±０．０４ｍｇ／ｍｌ。而３７℃灭活的ｐＨＧＦ对ＢＥＬ－７４０２细胞增殖在１５ｈ无抑制作用，在２４和４８ｈ抑制作用很弱（ＩＤ５０＞１．５ｍｇ／ｍｌ）。ＤＮＡ凝胶电泳结果表明，ｐＨＧＦ可诱导ＢＥＬ７４０２细胞产生细胞凋亡（Ａｐｏｐｔｏｓｉｓ）。流式细胞术（ＦＣＭ）结果显示：ｐＨＧＦ抑制ＢＥＬ－７４０２细胞增殖过程是先使细胞停留在Ｇ０／Ｇ１期，继而诱导细胞产生凋亡。后两项结果均显示ｐＨＧＦ对人肝癌细胞凋亡的诱导里时间和剂量相关性。     

医学毕业生心理调查分析及对策

目的调查分析医学毕业生心理,采取教育对策。方法应用Zung焦虑抑郁自评量表(SAS、SDS)对医学院校187名应届医学毕业生进行抽样调查。结果本组SAS、SDS标准分平均值为37.04±9.08与40.18±10.57;SAS男性37.07±9.38,与女性略同;SDS男性40.55±10.95高于女性39.90±10.30,差异不显著。SAS、SDS≥50的高分人数57例,占30.46%,其中≥50轻度焦虑抑郁为19.24%,≥60重度焦虑11.22%;男、女性别组焦虑抑郁者分别为25例与33例,各占28.09%与33.67%,女性轻度抑郁比例多于男性,差异显著。结论本组医学生情绪状态整体水平尚可,少数学生偏离正常。女性焦虑抑郁人数分布高于男性。应加强素质教育,开展心理咨询,完善就业工作体制,拓宽就业渠道。     

超声波介导的基因输送技术

近年来超声波介导的基因输送技术由于其相对安全性和操作上的简单得到关注。本文对超声波导致的声致穿孔的机制,空化核的作用——增强基因输送的效率,以及细胞和在体基因输送效率作了综述,讨论了超声波介导的基因输送效率的影响因素。此方法充满希望并且载药的空泡可以作为一种新型药物载体在超声作用下实现药物的靶向输送     

一种可生物降解温度敏感型聚乙二醇-聚己内酯-聚乙二醇水凝胶的合成和表征

合成了一系列分子量较低的聚乙二醇．聚己内酯-聚乙二醇（Poly（ethylene glycol）-Polycaprolactone-Poly（ethylene glycol），PEG-PCL—PEG）三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性，当水溶液浓度高于临界凝胶浓度（Critical gel concentration，CGC）时，随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度，以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件，可以在一定程度上拓宽凝胶-溶胶转变温度范围，有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。     

Retinal dehydrogenase-2 is inhibited by compounds that induce congenital diaphragmatic hernias in rodents

Currently, the etiology of the serious developmental anomaly congenital diaphragmatic hernia (CDH) is unknown. We have used an animal model of CDH to address this issue. We characterized four separate teratogens that produced diaphragmatic defects in embryonic rats that are similar to those in infants with CDH. We then tested the hypothesis that all these agents share the common mechanism of perturbing the retinoid-signaling pathway. Specifically, inhibition of retinal dehydrogenase-2 (RALDH2), a key enzyme necessary for the production of retinoic acid and that is expressed in the developing diaphragm, was assayed by measuring retinoic acid production in cytosolic extracts from an oligodendrocyte cell line. The following compounds all induce posterolateral defects in the rat diaphragm; nitrofen, 4-biphenyl carboxylic acid, bisdiamine, and SB-210661. Importantly, we demonstrate that they all share the common mechanism of inhibiting RALDH2. These data provide an important component of mounting evidence suggesting that the retinoid system warrants consideration in future studies of the etiology of CDH.