用电子自旋共振成像观测氮氧自由基的透皮特性

在自行研制的电子自旋共振成像(Electron spin resonance imaging, ESRI)系统上建立了活体皮肤电子自旋共振成像的实验模型.观测了氮氧自由基化合物2,2,6,6-四甲基哌啶-1-氧(2,2,6,6-tetramethyl-1-piperidinyloxy,TEMPO)穿透小鼠皮肤组织的动态过程和浓度分布情况.成像结果显示TEMPO化合物对不同方法处理后的皮肤组织的透皮特性有明显差别.TEMPO水溶液难以穿透皮肤,而溶解在二甲基亚枫(Dimethyl sulfoxide,DMSO)中的脂溶性TEMPO溶液可以渗入并穿透皮肤.皮肤表层的角质蛋白对TEMPO有明显的阻隔性, 而且化合物渗入或透过皮肤组织的量具有较强的时间依赖性.本研究结果提示ESRI技术为动态研究某些特殊结构化合物的透皮特性提供了科学有效的分析手段.     

胰岛素样生长因子Ⅱ在肝细胞癌的免疫组化研究

以兔抗胰岛素样生长因子Ⅱ(IGF-2)的抗体,ABC法,对50例肝癌石蜡切片染色,结果:(1)正常肝有极微弱阳性,表明可分泌少量IGF-2;(2)癌旁肝27例,全部阳性,“++”者19例(70%),表明有大量IGF-2产生和存在;(3)50例肝癌,48例(96%)阳性,IGF-2呈胞浆弥散型分布,其中26例(52%)呈较强阳性(++),8例核内也有IGF-2,表明癌细胞能自己合成IGF-2为其恶性增殖创造条件,且不因分化程度之降低而有所减少;(4)IGF-2呈较强阳性(++)之细胞(包括小多角形肝细胞)既见于癌周肝,又见于慢性肝炎,表明胰岛素样生长因子Ⅱ直接和增殖而非与癌变相关。     

NOD小鼠胸腺细胞TCR介导的信号通路缺陷

目的 进一步研究NOD小鼠T细胞应答改变机理。方法 用抗TCR抗体、ConA激活NOD小鼠胸腺细胞，分析TCR介导的信号通路的水平。结果 与Balb／c小鼠胸腺细胞相比，抗TCR抗体诱导的增殖应答较弱，与年龄及NOD胸腺CD4^ CD8^-和CD4^-CD8^ SP细胞有关；rIL-2能部分恢复对TCR抗体应答的缺乏。NOD小鼠对PMA IONO和PMA anti—TCR-mAb应答正常，但对anti-TCRmAb IONO应答缺乏。结论 与年龄有关的NOD小鼠胸腺细胞对TCR抗体应答的缺乏与T细胞激活时上游PKC信号通路的缺乏有关。     

MTHFR基因多态性对血管内皮功能指标的影响

目的：研究社区人群中MTHFR 677C→T基因突变对血管紧张素Ⅱ、前列环素和一氧化氮水平的影响。方法：整群抽取社区汉族成年居民1 146人，采用PCR－RFLP鉴定目标人群MTHFR 677位基因型；采用荧光生化技术测定血浆Hcy浓度；用镉还原法检测其血清一氧化氮水平，用放射免疫分析法检测血浆血管紧张素Ⅱ和前列环素的浓度。所有数据用SPSS 13.0 软件进行统计分析。结果：1 146例居民按MTHFR 677基因型自然分组，三组之间PGI₂、AngⅡ没有统计学差异；C/C和T/C基因型组之间血清NO水平无显著差异（P>0.05），T/T基因型组的血清NO水平较C/C和T/C基因型组都低（P＜0.01）。结论:社区人群中MTHFR 677C→T突变对血浆PGI₂、AngⅡ的影响并不明显；血清NO水平下降，可能是MTHFR 677C→T导致缺血性心脑血管病的机制之一。     

人工髓核材料-聚乙烯醇水凝胶/聚乙烯纤维复合物的生物相容性研究*

目的评估人工髓核材料聚乙烯醇水凝胶/聚乙烯纤维复合物的生物相容性。方法根据ISO10993-1标准,采用细胞毒性试验(琼脂扩散法)、皮内刺激试验、Ame's致突变试验、微核试验和体内植入(360天)试验对聚乙烯醇水凝胶/聚乙烯纤维复合物的生物相容性进行评估。结果聚乙烯醇水凝胶/聚乙烯纤维复合物的细胞毒性评分小于Ⅰ级,细胞生长无明显抑制现象,对皮内无刺激作用,Ames致突变试验为阴性,微核出现率为3.48‰,无致突变反应。体内植入符合植入材料生物学评价要求。结论聚乙烯醇水凝胶/聚乙烯纤维复合物具有良好的生物安全性,是一种无毒、对皮肤及肌肉、椎间隙无刺激作用的生物医用材料,在动物体内不引起排异反应,可应用于临床。     

Efficacy of traditional Chinese herbs on squamous cell carcinoma of the esophagus: histopathologic analysis of 240 cases

Three types of traditional Chinese herb medicine were used to treat 98 patients with advanced esophageal squamous cell carcinoma prior to surgical treatment. Forty-two patients with the same diagnosis were treated with these herbs plus cyclophosphamide (endoxan). One hundred similar patients received surgical treatment without herbs or endoxan treatment as controls. Histologic examinations of surgical specimens were made on all of these patients. Stromal lymphoid-cell infiltration and cancer tissue degeneration were more prominent in Menispernum dehuricum DC- or Chelidonium majus L-treated patients, and were less clear in patients treated with herbs plus endoxan and the controls. The antitumor action of herbs is thought to be brought about by the activation of an immunological rejection mechanism. Herbs plus endoxan may result in the masking of the immunological response of hosts without obviously damaging cancer tissues.     

Adult-onset type II citrullinemia and idiopathic neonatal hepatitis caused by citrin deficiency: involvement of the aspartate glutamate carrier for urea synthesis and maintenance of the urea cycle

Citrin is a mitochondrial aspartate glutamate carrier primarily expressed in the liver, heart, and kidney. We found that adult-onset type II citrullinemia is caused by mutations in the SLC25A13 gene that encodes for citrin. In this report, we describe the frequency of SLC25A13 mutations, the roles of citrin as a member of the urea cycle and as a member of the malate-aspartate shuttle, the relationship between its functions and symptoms of citrin deficiency, and therapeutic issues.