自身免疫性肝炎的特异性T淋巴细胞免疫

自身免疫性肝炎(AIH)是一种器官特异性自身免疫性疾病,以肝组织内T淋巴细胞浸润、高Y球蛋白血症、血清自身抗体阳性、具有人类白细胞抗原(HLA)遗传背景、常伴发其他自身免疫性疾病和对免疫抑制治疗有效为特征[1].自身免疫反应介导的肝细胞损伤是AIH发病机制之一,且遗传因素也参与了AIH的发病,而在AIH免疫发病机制方面,自身反应性T淋巴细胞,尤其是AIH靶抗原特异性T淋巴细胞起至关重要的作用,但具体机制尚未阐明. 一、AIH特异性靶抗原的认识 自身抗原是自身抗体和自身反应性T淋巴细胞作用的靶点,是自身免疫反应的基础.自身抗原必须满足4个条件:(1)必须存在一个相应的高滴度器官特异性自身抗体;(2)需证实T淋巴细胞对相对应的抗原致敏;(3)存在疾病特异性的B淋巴细胞和T淋巴细胞表位;(4)需有抗体和(或)自身反应性T淋巴细胞致病的证据.     

自身免疫性肝炎的临床诊治

自身免疫性肝炎(AIH)是由异常自身免疫反应介导的肝实质炎症性病变,以高丙种球蛋白血症、血清自身抗体阳性和对免疫抑制治疗应答为特点[1].在环境因素、免疫耐受失衡和遗传易感状态的共同作用下,机体出现T淋巴细胞介导的针对肝抗原的异常免疫攻击,进而导致肝内进行性炎症坏死和纤维化过程.     

自身免疫性甲状腺炎自身抗原的研究进展

自身免疫性甲状腺炎是器官特异性的自身免疫性疾病,甲状腺组织存在特有的自身抗原成分,可刺激机体生成自身抗体与甲状腺组织上的自身抗原结合,引起免疫应答反应,继而发生免疫性的组织损伤。目前已了解有甲状腺球蛋白（Ｔｇ）、甲状腺过氧化物酶（ＴＰＯ）、促甲状腺激素受体（ＴＳＨ－Ｒ）、甲状腺激素（Ｔ３、Ｔ４）、甲状腺细胞膜及甲状腺的胶质成分等多种甲状腺自身抗原。在这些自身抗原中,Ｔｇ和ＴＰＯ可免疫动物诱导为实验性自身免疫性甲状腺炎（ＥＡＴ）,一般考虑Ｔｇ和ＴＰＯ可能是参与自身免疫性甲状腺炎发生的主要自身抗原［…     

自身免疫性肝病的病理学新进展

自身免疫性肝病是指由于机体免疫系统攻击自体肝组织引起的肝组织损伤和肝功能异常的一组免疫性疾病,包括有自身免疫性肝炎(AIH)、原发性胆汁性肝硬化(PBC)和原发性硬化性胆管炎(PSC).通常情况下这三种肝脏疾病独立存在,约有6％～9％的患者可以在同一时段或病程中出现两种疾病的临床表现、血清学和组织学特征,称为重叠综合征.近年来随着对自身免疫性肝病认识水平的提高以及自身抗体检测方法的不断改进,一些学者在自身免疫性肝病的经典肝组织学病变特点的基础上,提出了一些见解,介绍如下.     

药物性肝损害伴自身抗体阳性患者临床特征及转归

随着自身抗体检测技术的提高及临床医帅对自身免疫性肝病认识程度的不断提高,肝功能异常伴自身抗体阳性特别是高滴度自身抗体阳性患者的诊断、鉴别诊断及治疗问题越来越受到临床医师的关注,因为自身抗体阳性虽是诊断自身免疫性肝病的主要条件之一,但在部分病毒性肝炎、药物性肝损害、酒精性及非酒精性脂肪性肝炎中也均可检测到自身抗体,特别是非特异性自身抗体,如抗核抗体、抗线粒体抗体及抗平滑肌抗体等,是一种疾病伴随自身免疫现象还是两种疾病共同存在,如何诊断及鉴别诊断,有时成为摆在临床医师面前较棘手的问题,也是临床亟待解决的问题,此节主要讨论药物性肝损害患者检测出自身抗体时如何诊断及治疗,是药物诱导了自身免疫样肝炎还是药物伴随自身免疫现象?如何与自身免疫性肝炎鉴别?因自身免疫性肝炎治疗需较长期应用激素及免疫抑制剂,而非自身免疫性肝炎患者短期应用或不应用上述治疗.如上述诊断及鉴别诊断不全面,使治疗不得当,会加重或延误病情,给患者带来痛苦.     

调节性T淋巴细胞与HBV感染慢性化的关系

调节性T淋巴细胞是抑制机体免疫应答,诱导机体免疫耐受的一种T淋巴细胞亚群,是近年来免疫学领域研究的热点之一。调节性T淋巴细胞功能紊乱和数量上的变化与自身免疫性疾病、感染性疾病、肿瘤免疫耐受、移植排斥以及过敏性疾病的进程和治疗密切相关。归纳了近几年调节性T淋巴细胞的表面标志、免疫机制及其与乙型肝炎发病和抗病毒治疗过程的关系。     

调节性B淋巴细胞在自身免疫性肝炎发生发展中的作用机制

自身免疫性肝炎是一种自身免疫性疾病,目前机制不清,主要认为与机体免疫失衡有关。炎症性疾病中调节性B淋巴细胞(Breg)主要通过分泌IL-10抑制炎症反应,抑制CD4+T淋巴细胞分化为辅助性T淋巴细胞1和辅助性T淋巴细胞17。自身免疫性肝炎患者外周血IL-10水平降低,Breg数量及功能降低,导致其不能有效的抑制炎症反应,提示Breg在自身免疫性肝炎发病起到了一定的作用。综述了Breg亚群在自身免疫性肝炎中的作用机制。     

慢性丙型肝炎合并自身免疫性疾病的诊治

丙型肝炎病毒感染除造成持续肝脏损伤,导致肝硬化和肝癌外,还常常引起许多肝外自身免疫现象,诸如自身 抗体产生、混合性冷球蛋白血症、自身免疫性甲状腺疾病等。慢性丙型肝炎合并自身免疫性疾病的临床表现复杂, 病情轻重不一,诊断难度较大。由于目前尚无统一治疗指南,治疗方案应涵盖针对病因、发病机制和对症治疗三个 部分,并强调个体化治疗的重要性。     

TSHR与自身免疫性甲状腺疾病关系的研究进展

自身免疫性甲状腺疾病（AITD）是一组器官特异性自身免疫性疾病，促甲状腺素受体（TSHR）是其重要的自身抗原，在遗传和环境因素共同作用下，可以诱导机体产生特异性抗体，即TSHR抗体（TRAb)，它介导损伤性免疫应答，TSHR基因突变可能与AITD的发生有关。     

TSHR与自身免疫性甲状腺疾病关系的研究进展

自身免疫性甲状腺疾病 (AITD)是一组器官特异性自身免疫性疾病 ,促甲状腺素受体 (TSHR)是其重要的自身抗原 ,在遗传和环境因素共同作用下 ,可以诱导机体产生特异性抗体 ,即TSHR抗体 (TRAb) ,它介导损伤性免疫应答。TSHR基因突变可能与AITD的发生有关     

A Call to Action to Enhance Filovirus Disease Outbreak Preparedness and Response

The frequency and magnitude of recognized and declared filovirus-disease outbreaks have increased in recent years, while pathogenic filoviruses are potentially ubiquitous throughout sub-Saharan Africa. Meanwhile, the efficiency and effectiveness of filovirus-disease outbreak preparedness and response efforts are currently limited by inherent challenges and persistent shortcomings. This paper delineates some of these challenges and shortcomings and provides a proposal for enhancing future filovirus-disease outbreak preparedness and response. The proposal serves as a call for prompt action by the organizations that comprise filovirus-disease outbreak response teams, namely, Ministries of Health of outbreak-prone countries, the World Health Organization, Médecins Sans Frontières, the Centers for Disease Control and Prevention—Atlanta, and others.     

Control of intraabdominal hemorrhage and shock: a comparison of fluid resuscitation, MAST, and balloon occlusion

Our study examined the efficacy of four treatment modalities in controlling hemorrhage and achieving hemodynamic stabilization in hemorrhagic shock: intravenous fluid replacement (IV); military antishock trousers used concomitantly with fluids (MAST); balloon occlusion at the level of the diaphragm with concomitant fluid replacement (balloon); and a combination of MAST inflation, balloon occlusion, and fluid resuscitation (MAST and balloon). Twenty-eight mongrel dogs were anesthetized, and the spleen was exposed and completely crushed. The abdomen was closed, and treatment was initiated and continued for four hours or until the dog died. For all conditions the hematocrit dropped during the course of the experiment; balloon occlusion was effective at slowing this drop (P less than .0001), but MAST had no statistically significant effect. Animals with balloons bled more slowly into the abdominal cavity than did animals in the other two groups (P less than .0001). MAST also were effective at slowing the bleeding (P less than .05). Of the balloon and the MAST and balloon dogs, all except one survived the entire four hours; this difference between balloon and nonballoon dogs is significant (P = .002). MAST did not have a statistically significant effect on survival. Perfusion pressure (PP) declined during the course of the experiment, and the balloon was effective at slowing this decline (P less than .0001); none of the other comparisons was statistically significant.     

Interplay between interferon-mediated innate immunity and porcine reproductive and respiratory syndrome virus

Innate immunity is the first line of defense against viral infection, and in turn, viruses have evolved to evade host immune surveillance. As a result, viruses may persist in host and develop chronic infections. Type I interferons (IFN-α/β) are among the most potent antiviral cytokines triggered by viral infections. Porcine reproductive and respiratory syndrome (PRRS) is a disease of pigs that is characterized by negligible induction of type I IFNs and viral persistence for an extended period. For IFN production, RIG-I/MDA5 and JAK-STAT pathways are two major signaling pathways, and recent studies indicate that PRRS virus is armed to modulate type I IFN responses during infection. This review describes the viral strategies for modulation of type I IFN responses. At least three non-structural proteins (Nsp1, Nsp2, and Nsp11) and a structural protein (N nucleocapsid protein) have been identified and characterized to play roles in the IFN suppression and NF-κB pathways. Nsp's are early proteins while N is a late protein, suggesting that additional signaling pathways may be involved in addition to the IFN pathway. The understanding of molecular bases for virus-mediated modulation of host innate immune signaling will help us design new generation vaccines and control PRRS.     

Disease Pandemics and Major Epidemics Arising From New Encounters between Indigenous Viruses and Introduced Crops

Virus disease pandemics and epidemics that occur in the world’s staple food crops pose a major threat to global food security, especially in developing countries with tropical or subtropical climates. Moreover, this threat is escalating rapidly due to increasing difficulties in controlling virus diseases as climate change accelerates and the need to feed the burgeoning global population escalates. One of the main causes of these pandemics and epidemics is the introduction to a new continent of food crops domesticated elsewhere, and their subsequent invasion by damaging virus diseases they never encountered before. This review focusses on providing historical and up-to-date information about pandemics and major epidemics initiated by spillover of indigenous viruses from infected alternative hosts into introduced crops. This spillover requires new encounters at the managed and natural vegetation interface. The principal virus disease pandemic examples described are two (cassava mosaic, cassava brown streak) that threaten food security in sub-Saharan Africa (SSA), and one (tomato yellow leaf curl) doing so globally. A further example describes a virus disease pandemic threatening a major plantation crop producing a vital food export for West Africa (cacao swollen shoot). Also described are two examples of major virus disease epidemics that threaten SSA’s food security (rice yellow mottle, groundnut rosette). In addition, brief accounts are provided of two major maize virus disease epidemics (maize streak in SSA, maize rough dwarf in Mediterranean and Middle Eastern regions), a major rice disease epidemic (rice hoja blanca in the Americas), and damaging tomato tospovirus and begomovirus disease epidemics of tomato that impair food security in different world regions. For each pandemic or major epidemic, the factors involved in driving its initial emergence, and its subsequent increase in importance and geographical distribution, are explained. Finally, clarification is provided over what needs to be done globally to achieve effective management of severe virus disease pandemics and epidemics initiated by spillover events.     

岳阳市城区小学生血吸虫病防治健康教育现状调查

目的 调查湖南省岳阳市城区小学生血吸虫病防治知识、行为现状及健康教育需求情况,为制定科学有效的小学生血吸虫病健康教育方案提供参考依据。方法 采用分层整群抽样方法,抽取岳阳市城区洞庭湖湖畔学校和中心城区学校各2所,每所再从五、六年级分别抽取2个班的学生,通过调查问卷了解小学生血吸虫病相关知识、预防行为及健康教育需求,并进行统计分析。结果 共调查湖畔小学353人、中心城区小学363人,两组学校小学生年龄、性别、年级构成差异无统计学意义（t=-0.494,χ²_性别=1.615,χ²_年级=2.152;P均>0.05）。学生血吸虫病防治知识总知晓率为42.60%（305/716）,其中,湖畔学校小学生血防知识知晓率（52.97%）高于中心城区（32.51%）,差异有统计学意义（χ²=30.661,P<0.05）;学生行为正确率为76.68%（549/716）,血防知识知晓组行为正确率（81.31%）高于不知晓组（71.24%）,差异有统计学意义（χ²=6.384,P<0.05）。学生血防知识主要来源于老师（47.49%）;91.90%的学生愿意了解更多的血防知识,最喜欢的血防知识学习方式是参加课外活动（50.42%）。结论 岳阳市城区小学生的血防知识知晓率及行为正确率偏低,对血吸虫病防治健康教育需求较高。建议针对学生开展形式多样的血防健康教育,以增强学生的血吸虫病防护意识,提高自我防护能力。     

Barrett's Esophagus: Where Do We Stand?

Barrett''s esophagus (BE) is a precursor for esophageal adenocarcinoma, which has an increased incidence rate over the last few decades. Its importance stems from the poor five-year survival of esophageal adenocarcinoma and current data that suggest a survival benefit when surveillance programs are implemented. In this review, we will cover the pathophysiology and natural history of BE and the different endoscopic findings. The prevalence of BE in different geographic areas and the incidence of high-grade dysplasia and adenocarcinoma in this patient population is reviewed. Recent recommendation for screening and surveillance of BE has been covered in this review as well as the efficacy of nonconventional imaging modalities and endoscopic ablation therapies.