巨细胞病毒感染对动脉粥样硬化的影响

目的：研究巨细胞病毒(CMV)感染和动脉粥样硬化的关系，并探讨其可能机制。方法：通过一个大样本从血清流行病学(ELISA检测患者血清中抗CMV的IgG抗体)和分子生物学(PCR检测动脉粥样硬化病变中CMV特异性基因)方面探讨巨细胞病毒感染和动脉粥样硬化的关系，并检测CMV感染对内皮细胞趋化因子表达的影响。结果：动脉粥样硬化组血清中CMV的阳性率显著高于非动脉粥样硬化组(分别为82．2％和61．0％，P=0．02)；而且动脉粥样硬化斑块中HCMV基因出现率显著高于正常血管组织(13／15和2／7，P=0．01)；CMV感染还可上调内皮细胞：ECV-304表达MCP-1。结论：CMV感染参与动脉粥样硬化的形成和发生，这可能与CMV上调内皮细胞趋化因子表达有关。     

PD98059对人骨髓间质干细胞分化为成骨细胞的影响

目的:探讨胞外信号调节激酶(ERK)信号传导途径对骨髓间质干细胞(MSC)分化为成骨细胞的影响。方法:采用Ficoll-Paque淋巴细胞分离液分离成人MSC,体外扩增,应用地塞米松、β-甘油磷酸钠、vitaminC定向诱导MSC分化为成骨细胞。在成骨诱导液中加入不同剂量的PD98059,观察其对成骨细胞形成的影响。结果:MSC体外扩增15代可获得(3-4)×10¹²个细胞。在成骨诱导液作用下,MSC可在体外定向分化为成骨细胞。不同剂量的PD98059均可抑制MSC分化为成骨细胞,并有剂量依赖关系;同时促使部分细胞转化为脂肪细胞。结论:ERK信号传导途径可能在MSC分化为成骨细胞和脂肪细胞过程中起关键作用。     

Treatment of motoneuron degeneration by intracerebroventricular delivery of VEGF in a rat model of ALS

Neurotrophin treatment has so far failed to prolong the survival of individuals affected with amyotrophic lateral sclerosis (ALS), an incurable motoneuron degenerative disorder. Here we show that intracerebroventricular (i.c.v.) delivery of recombinant vascular endothelial growth factor (Vegf) in a SOD1(G93A) rat model of ALS delays onset of paralysis by 17 d, improves motor performance and prolongs survival by 22 d, representing the largest effects in animal models of ALS achieved by protein delivery. By protecting cervical motoneurons, i.c.v. delivery of Vegf is particularly effective in rats with the most severe form of ALS with forelimb onset. Vegf has direct neuroprotective effects on motoneurons in vivo, because neuronal expression of a transgene expressing the Vegf receptor prolongs the survival of SOD1(G93A) mice. On i.c.v. delivery, Vegf is anterogradely transported and preserves neuromuscular junctions in SOD1(G93A) rats. Our findings in preclinical rodent models of ALS may have implications for treatment of neurodegenerative disease in general.     

The minor outer capsid protein P2 of rice gall dwarf virus has a primary structure conserved with, yet is chemically dissimilar to, rice dwarf virus P2, a protein associated with virus infectivity

Summary. The nucleotide sequence of the genome segment 2 (S2) of rice gall dwarf virus (RGDV), a phytoreovirus, when compared with the amino acid sequence of a component protein of the virus, showed that S2 potentially encoded a 127K minor outer capsid protein. This 127K protein designated as P2 and the 127K minor outer capsid protein (also termed P2) of rice dwarf virus (RDV) are similar in size, located in the outer capsid, and have well-conserved predicted polypeptide sequences, suggesting similar functions. Infectivity to insect vector cell monolayers of RGDV was maintained and the P2 protein was retained irrespective of carbon tetrachloride (CCl₄) treatment. This is in contrast to the infectivity of RDV which is removed along with P2 protein following CCl₄ treatment. RGDV with P2 was acquired by vector insects and transmitted to host plants, although RDV lacking P2 could not be transmitted to plants as previously published. These results imply that RDV and RGDV require P2 proteins for virus infectivity to vector insects. Received January 6, 1997 Accepted May 14, 1997     

RAAS系统在继发性高血压疾病中的应用进展

在人体体内分布最广泛的内分泌调节系统是肾素-血管紧张素-醛固酮系统(renin-angiotensin-aldosteron system,RAAS),该系统在内分泌调节环节中发挥着至关重要的作用.在内分泌系统中,可以通过RAAS来实现对人体体内血量流动和外周阻力的控制,并且还可以通过RAAS来进一步调节体内血压、水和电解质的平衡,确保人体环境能够保持在一个稳定的状态.组成RAAS的主要部分有肾素、血管紧张素和醛固酮.针对RAAS各个组成部分进行深入研究之后,发现在RAAS系统中的一些部分与嗜铬细胞瘤、副神经节瘤等继发性高血压疾病密切相关.通过检测RAAS的组分可以辅助诊断因RAAS系统失调所导致的多种疾病.本文将从RAAS组分的检测方法及其在继发性高血压中的临床应用进行综述.     

头颈部肿瘤射野摆位误差的差异性研究

目的：研究采用电子射野系统评价头颈部肿瘤患者摆位误差时的观察者间变异和观察者自身变异。方法：两队研究小组，分别由四名医师和四名技师组成，两组分别对6名头颈部肿瘤的患者，采用电子射野影像仪（electronic portal imaging device，EPID）拍摄验证片（electronic portal images，EPIs），在EPIs上勾画骨性标志，以放疗计划生成的数字重建图像（digitally reconstructed radiographs，DRRs）做为参考图像，定量分析不同观察研究人员之间和研究人员自身采用EPID确定头颈部肿瘤患者的射野摆位误差（field placement errors，FPEs）的差异性。结果：在前／后位射野图像上．不同医师之间、医师自身及技师自身对摆位误差的判断无明显差异，但在技师之间出现了明显的自身差异性．医师组和技师组在前／后射野图像上的均方根（root-mean—square，RMS）分别为2．52±0．46和3．43±0．43，两者具有明显差异；在侧位野图像上，医师自身对摆位误差的判断有较好的稳定性，但部分不同医师之间在腹背、头足方向上部分患者中出现差异，而不同的技师之间存在明显差异性，医师组和技师组在侧位射野图像上的RMS分别为2．72±0．16和2．62±0．22．两者无明显差异。结论：医师和技师组在采用电子射野系统对头颈部摆位误差进行判断时存在人员之间的误差，应对所有人员进行统一训练才能减少射野摆位误差，从而提高IMRT治疗效果。     

白细胞介素-1基因多态性与高血压易感性的研究

目的　观察白细胞介素 - 1(interleukin- 1,IL- 1)基因多态性在中国汉族人群中的分布及其与原发性高血压 (essential hypertension,EH)的关系 ,初步分析其基因型与 EH易感性的相关性。方法　应用聚合酶链反应和限制性片段长度多态性的方法 ,检测湖北省汉族 15 2例 EH患者和 16 8名正常对照者的IL- 1基因多态性 ,包括 IL- 1α(- 889C/ T)位点、IL- 1β(- 5 11C/ T)位点、IL- 1β( 395 3C/ T)位点、IL- 1Ra( 80 0 6 T/ C)位点多态性以及 IL- 1Ra第 2内含子可变数串联重复序列多态性。结果　IL- 1α(- 889C/ T)位点、IL- 1β( 395 3C/ T)位点、IL- 1Ra( 80 0 6 T/ C)位点多态性和 IL- 1Ra可变重复序列多态性在 EH组和正常人群中的分布差异无显著性 (P>0 .0 5 ) ,而 IL- 1β(- 5 11C/ T)位点多态性在两组人群中的分布差异存在显著性 (P<0 .0 5 ) ,携带 CT基因型罹患 EH的危险性可增加 2 .5 4倍。结论　 IL- 1β基因启动子区 - 5 11位点 C/ T多态性可能与 EH易感性存在相关关系。     

SARS coronavirus induces apoptosis in Vero E6 cells

Severe acute respiratory syndrome (SARS) is an emerging infectious disease. Its etiological agent has been convincingly identified as a new member of family Coronaviridae (SARS-CoV). It causes serious damage to the respiratory system yet the mechanism is not clear. Infection-induced apoptosis or necrosis is suspected but no direct evidence for this yet exists. To date, Vero E6 cells are the only cell line that could be used to replicate the virus with obvious CPE (cytopathic effect) in vitro. It is known for some viruses (including members of family Coronaviridae) that CPE can be caused either by virus-induced apoptosis (active death) or cell necrosis (passive death). In this study, we examined the apoptosis in the SARS-CoV infected Vero E6 cells. Indeed, the results do show that the CPE was induced by apoptosis rather than necrosis, shown by typical DNA fragmentation, through the existence of apoptotic bodies and swollen mitochondria. This observation has some implications for the SARS-CoV pathogenicity: SARS-CoV does induce apoptosis in cell cultures and might have the same effect in vivo, responsible for the severe damage of the respiratory system.     

中国东北地区未经抗病毒治疗的HIV/AIDS患者HIV毒株的耐药基因变异研究

目的　研究我国东北地区未接受抗逆转录病毒治疗的HIV AIDS患者HIV毒株的逆转录酶和蛋白酶耐药变异情况 ,为开展大规模临床抗病毒药物治疗提供本底数据。方法　RT PCR和套式PCR扩增HIVpol区基因 ,双脱氧法测定逆转录酶和蛋白酶基因序列 ,与国际耐药数据库比对辨别耐药变异。结果　 (1) 5 3例患者毒株亚型分析结果 :B′亚型 4 7例 ,B′ C亚型 4例 ,A、B亚型各 1例 ;(2 )未发现逆转录酶和蛋白酶原发耐药变异存在 ,但发现存在逆转录酶抑制剂继发变异 :M4 1L(1.9% )、I6 3M (1.9% )、L74I (1.9% )、S6 8G (1.9% )、V75L (3.8% )、V10 6I (1.9% )、I135L T (5 .7% )、V179D (7.5 % )和V189I (1.9% ) ,无症状感染者RT继发耐药变异出现率为 11.8% ,而艾滋病患者为5 2 .6 % (P <0 .0 1)。存在大量蛋白酶耐药继发变异V77I (88.7% )、L6 3P (86 .8% )、E35D (81% )、A71V(2 4 .5 % )、R4 1K (15 .1% )、L10I (9.4 % )、R5 7K (9.4 % )、D6 0E (9.4 % )、N37D (5 .7% )、G16E (3.8% )、I15V (1.9% )、M36I (1.9% )、K5 5R (1.9% )和L89M (1.9% )。未发现明显的亚型特异性耐药变异。结论　在中国东北地区未接受抗逆转录病毒治疗的HIV AIDS患者中未发现毒株逆转录酶和蛋白酶耐药原发变异 ,但大量继发耐药变异的存在提     

天然免疫模式识别途径:胞外识别与胞内识别

天然免疫系统通常籍模式识别受体识别病原体相关分子模式。取决于感染的性质,模式识别受体通过细胞外 或细胞内途径识别病原体,并传导相应的信号,激活宿主防御应答,消灭入侵病原体。