Expression of PADI4 in hepatocellular carcinoma

Objective： The aim of the research was to study peptidylarginine deiminase type 4 （PAD4/PADI4） expression and its tumodgenic mechanism in hepatocellular carcinomas. Methods： Expressions of PADI4 and p53 were investigated in tumors and non-tumor tissues by Western blot in patients with hepatocellular carcinomas. We constructed plasmid of PADI4-Flag and transfected it in Hela cells to investigate the mechanism. Results： Western blot analysis showed higher PADI4 expression in hepatocellular carcinomas than in the surrounding healthy tissues. Furthermore, by Western blot, we detected decreased p53 levels in the tumor tissues of patients with hepatocellular carcinomas compared to surrounding healthy tissues. In Hela cells transfected with PcDNA3.0-Flag-PADI4 plasmid, the expression of p53 decreased obviously. Conclusion： Our results suggest that PADI4 elevated in the tissues of hepatocellular carcinomas and induced tumorigenic by down-regulating p53 expression.     

Effect of chromatic mechanisms on the detection of mesopic incremental targets at different eccentricities

Spectral sensitivity functions for the threshold detection of mesopic incremental targets were compared for different target eccentricities (10, 20, and 30°) and for different mesopic backgrounds (0.1, 0.5 and 1.0 cd m⁻²). Relative responsivities of achromatic mechanisms (L + M and rods) and chromatic mechanisms (S and |L–M|) were estimated for each eccentricity and background. Chromatic mechanisms contribute significantly to detection but their effect is lower at 30°. A new contrast metric ( C _CHC2) is introduced to account for the selective adaptation of the photoreceptors and the effects of the chromatic mechanisms i.e. broadening of the range of spectral sensitivity with multiple local maxima and yellow sub-additivity of detection performance. The C _CHC2 metric is compared with the achromatic contrast metric of the MOVE model ( C _MOVE). For the same target, C _CHC2 generally predicts a higher visibility level than C _MOVE. However, in accordance with visual observations, for grey or yellowish incremental targets appearing at the eccentricities of 20 and 30°, the visibility predicted by C _CHC2 is less than the visibility predicted by C _MOVE.     

中药调控小胶质细胞极化平衡治疗神经退行性疾病的机制研究进展

神经炎症是神经退行性疾病（NDs）的共同病理特征，而小胶质细胞（MG）是具有独特发育起源的脑内常驻巨噬细胞，是神经炎症的核心驱动因素，可通过不同极化状态参与NDs的发生、发展过程，且在调节神经发生、突触塑造和维持体内平衡等方面发挥着关键作用。MG根据功能可分为M1促炎表型和M2抗炎表型，其中M1表型释放的炎症介质可导致神经变性和髓鞘损伤，而抑制炎症反应、促进组织修复则需要M2表型的激活。中药在多途径、多靶点及双向调节的优势下，可调控MG的极化平衡，且在阿尔茨海默病、帕金森病、多发性硬化等NDs中具有双重作用。中药活性成分及其复方可通过调控磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/Akt)、NOD样受体蛋白3(NLRP3)、信号转导及转录激活因子1(STAT1)、核转录因子-κB(NF-κB)等通路抑制MG的活化，促进M1型向M2型极化，减少白细胞介素（IL）-6、肿瘤坏死因子-α(TNF-α)等促炎因子的表达，增加IL-10、精氨酸酶-1(Arg-1)等抗炎因子的分泌，降低阿尔茨海默病中β-淀粉样蛋白沉积和Tau样蛋白表达、减轻帕金森病中多巴胺能神经元损伤、缓解多发性硬化的脱髓鞘、炎性...     

手舟骨骨折损伤机制分析

目的探讨手舟骨骨折的原因、机制，为减少手舟骨骨折的发生提供预防措施。方法2006年11月-2007年11月，临床收集手舟骨骨折病例16例，详细询问并记录病史，结合X片、CT表现，从物理力学的角度分析受伤机制。结果16例均为腕过伸位着地受伤；5例为军事训练（单双杠、倒功）中受伤，其中1例受伤时上臂呈后伸位，4例呈前屈位；8例为打球时受伤，其中2例受伤时上臂呈后伸位，6例呈前屈位；3例为高处坠落（2-6m）时受伤，均为上臂前屈位手掌着地所致。结节部骨折0例，远端（粉碎性骨折）3例，腰部横形骨折10例，斜形骨折3例，纵形骨折0例，近端骨折0例。结论手舟骨骨折主要发病原因为高强度训练、运动及高处坠落时腕关节过伸位手掌着地受伤。受伤时手掌的不同位置及人体的不同运动倾向综合作用，通过不同的损伤机制造成手舟骨不同类型的损伤。     

硒和维生素E对前列环素和血栓素合成的调控机制

前列环素（ＰＧＩ２）和血栓素（ＴＸＡ２）是一对生物功能相反的强烈的细胞生理调节剂，其生物合成是由花生四烯酸经前列腺素合酶催化生成ＰＧＨ２，再在前列环素合酶和血栓素合酶的作用下分别异构为ＰＧＩ２和ＴＸＡ２。由于过氧化物对前列腺素合酶、前列环素合酶和血栓素合酶的催化活性有不同影响，所以能控制体内过氧化物水平的抗氧化剂硒和维生素Ｅ对ＰＧＩ２和ＴＸＡ２的合成具有调控作用。硒和维生素Ｅ缺乏促进ＰＧＩ２／ＴＸＡ２比值下降，补硒和维生素Ｅ可以纠正这种作用     

Salivary gland extract from Ixodes ricinus ticks inhibits production of interferon-γ by the upregulation of interleukin-10

Tick saliva has been shown to modulate host immunity by a so far unknown mechanism. We have demonstrated an inverted effect of salivary gland extract (SGE), derived from partially fed Ixodes ricinus females, on the production of two cytokines, interferon (IFN)-gamma and interleukin (IL)-10, in vitro. While SGE markedly suppressed the elaboration of IFN-gamma by mouse splenocytes stimulated with lipopolysaccharide (LPS), the production of IL-10 was increased in comparison with SGE-untreated cultures. The suppressive effect of SGE could be abolished by the addition of an IL-10 neutralizing monoclonal antibody to splenocyte cultures. Similar results were obtained when live Borrelia afzelii spirochetes, which are transmitted in Europe by I. ricinus ticks, were used for the cytokine induction. These results suggest that tick saliva can upregulate the IL-10 production at the tick feeding site, which consecutively inhibits the elaboration of pro-inflammatory cytokines, for example IFN-gamma. This immunosuppression may facilitate the establishment of tick-transmitted pathogens in the host.     

乙二胺所致哮喘的临床免疫学研究

对5例EDA哮喘患者做了非特异性支气管激发试验,结果气道反应性轻度增高2例,中度增高3例。8例EDA哮喘患者做了特异性支气管激发试验,结果全部阳性,其中7例为迟发相反应,1例为双相反应。而普通哮喘组和正常对照组激发试验全部阴性。激发试验前后测定了总补体、组胺,作了嗜酸细胞计数。激发后EDA哮喘组嗜酸细胞明显增加,并有统计学意义(P<0.05),与普通哮喘组和正常对照组激发后嗜酸细胞计数比有显著差异(P<0.01)。EDA哮喘组激发后组胺释放增加(P<0.05)。EDA哮喘组总补体均未见有意义的改变。EDA-BSA皮内试验结果表明,EDA哮喘4例为阳性,普通哮喘组1例为阳性,而对照组无1例阳性。EDA-BSA作抗原,以酶联免疲分析证明了EDA哮喘组有3例有特异性IgG抗体,而其他两组未发现特异性IgG抗体,EDA哮喘组未检出特异性IgE抗体。     

载钯量对轻质烷烃异构化催化剂(Pd/HM)性能的影响

采用MR-GC80型压力微反装置,在空速2h~(-1)、氢油分子比8:1、氢压2MPa、反应温度260℃和280℃反应条件下,考察了钯/氢型丝光沸石(Pd/HM)催化剂的含钯量对正己烷异构化反应活性,选择性,稳定性的影响,并结合脉冲激反装置对反应机理进行了探讨。结果表明:钯含量在0.025—0.25%范围内,活性和选择性均随含钯量的增加而提高;超过0.85%,则呈下降趋势;HM载钯后稳定性有明显的改善。催速失活试验表明:0.25%Pd/HM和0.5% Pd/HM催化剂具有相同的稳定性。在Pd/HM上正己烷异构化反应的机理为酸性和双功能结合的复合机理。     

环境雌激素对生殖和发育毒性的分子机理

大量动物实验表明环境雌激素具有生殖和／或发育毒性，但其作用机制非常复杂，尤其在分子机理方面不甚明了，本文从信号通路，基因表达，诱变效应等几个方面介绍了近几年来国内外在分子机理研究方面所取得的进展。     

肿瘤热疗的临床应用研究进展

热疗是继手术、放疗、化疗之后一种全新的治疗肿瘤的“绿色疗法”。目前我国有微波热疗、超声聚焦热疗、射频热疗及内生场热疗。叙述了热疗在肿瘤治疗中的应用机制及各种热疗方法在，临床中的应用研究进展。