肺炎衣原体呼吸道感染发病机制研究进展

肺炎衣原体是人类呼吸道感染的常见致病原,目前对其导致呼吸道感染的发病机制尚不十分清楚。本文对国外近年来通过动物模型探讨肺炎衣原体呼吸道感染发病机制的研究进展作一综述。     

036 肺炎衣原体呼吸道感染发病机制研究进展

肺炎衣原体是人类呼吸道感染的常见致病原,目前对其导致呼吸道感染的发病机制尚不十分清楚.本文对国外近年来通过动物模型探讨肺炎衣原体呼吸道感染发病机制的研究进展作一综述.     

军团菌肺炎发病机制研究进展

军团菌肺炎是一种以肺炎为主要表现 ,常伴多系统损害的急性传染病。作为病原的军团杆菌已被发现有 42个种 6 4个血清型[1 ] ,至少有 1 9个种与人类疾病有关[2 ] ,其中嗜肺军团菌种 (Ｌｅｇｉｏｎｅｌｌａｐｎｅｕｍｏｐｈｌｉａ,Ｌｐ)与人类疾病的关系最为密切。我们以Ｌｐ为例 ,对此病发病机制研究进展进行综述 ,以助于加深对此病的认识。一、军团菌进入人体途径污染有此菌的小颗粒气浴胶可在吸入后直接穿入呼吸性细支气管和肺泡造成感染。含菌微粒的危害性取决于细菌的存活和稳定状态 ,后者又取决于细菌本身若干因素 ,包括代谢活性 ,侵入…     

肺炎衣原体呼吸道感染发病机制研究

肺炎衣原体是人类呼吸道感染的常见致病原,目前对其导致呼吸道感染的发病机制尚不十分清楚。本对国外近年来通过动物模型探讨肺炎衣原体呼吸道感染发病机制的研究进展作一综述。     

肺炎衣原体感染致动脉粥样硬化的发病机制

肺炎衣原体具有感染动脉的能力和途径；体外细胞培养和动物实验证实：在动脉粥样硬化形成的各阶段，肺炎衣原体与靶细胞相互作用，促进动脉粥样硬化的发生与发展，加速其进程；肺炎衣原体感染的兔模型能够发生动脉粥样硬化的病理变化；抗生素的干预具有抑制动脉粥样硬化形成的作用；基因多态性与基因突变影响个体对肺炎衣原体的易感性。     

肺炎衣原体感染致动脉粥样硬化的发病机制

肺炎衣原体具有感染动脉的能力和途径;体外细胞培养和动物实验证实:在动脉粥样硬化形成的各阶段,肺炎衣原体与靶细胞相互作用,促进动脉粥样硬化的发生与发展,加速其进程;肺炎衣原体感染的兔模型能够发生动脉粥样硬化的病理变化;抗生素的干预具有抑制动脉粥样硬化形成的作用;基因多态性与基因突变影响个体对肺炎衣原体的易感性.     

肺炎链球菌耐药性研究进展

肺炎链球菌是重要的致病菌,近年来肺炎链球菌对青霉素等多种药物的耐药性在全球普遍呈上升趋势。同时,分子生物学方法的应用使肺炎链球球菌耐药性的发生和传播机制得到了较全面的阐述。     

感染后咳嗽发病机制的研究进展

正日常生活中,咳嗽是呼吸道感染后引发的常见临床表现,咳嗽较重时常常会影响患者的正常工作,夜间咳嗽频繁者,会严重影响睡眠的质量~([1-3])。此外,长期咳嗽不能够治愈,还会给患者家庭以及社会带来一定的经济损失。目前对感染后咳嗽(post infectious cough,PIC)的发病机制,并没有     

肺炎链球菌蛋白质疫苗研究进展

随着肺炎链球菌(SP)耐药菌株的不断出现使得疫苗研发备受关注,但目前使用的荚膜多糖及其结合疫苗有很大局限性。因此,针对SP主要毒力因子的蛋白质疫苗迅速发展,其中SP单一蛋白质疫苗包括溶血素、表面蛋白A、表面黏附素A、三组氨酸蛋白D、黏附毒力因子A,蛋白质联合疫苗包括多价重组蛋白质联合疫苗、多价蛋白质融合疫苗,已取得一定实验和临床效果,有望替代多糖疫苗。     

HIV感染并发心血管疾病发病机制研究进展

随着高效抗反转录病毒治疗（HAART）的应用,心血管疾病（CVD）已经成为人类免疫缺陷病毒（HIV）感染者死亡的一个重要原因。据报道,HIV感染人群的CVD发病率至少是普通人群的3倍。因此,HIV感染并发CVD的发病机制成为艾滋病（AIDS）研究最关注的领域之一。现对HIV感染者独特的CVD危险因素及宿主、HIV和抗反转录病毒药物等三个方面致病机制研究的最新进展做一简要综述。     

The role of pneumolysin in the pathogenesis of Streptococcus pneumoniae infection

In addition to being cytotoxic for eukaryotic cells, recent research has clearly indicated that pneumolysin at sub-cytolytic concentrations potentiates the proinflammatory activities of neutrophils and macrophages. Together these cytotoxic and proinflammatory activities of the toxin are likely to contribute to the virulence of the pneumococcus, particularly in facilitating adherence, invasion and dissemination of this important microbial pathogen. Pneumolysin-based vaccine strategies, although in the early stages of development and evaluation, show promise in reducing the severity of pneumococcal disease.     

Hospital-acquired Streptococcus pneumoniae infection

Three elderly patients were consecutively found to harbor or to become infected with intermediate-level penicillin-resistant Streptococcus pneumoniae in a hospital respiratory ward. All the isolates from the respective patients produced mucoid-type colonies on sheep blood agar plates and were found to have an identical antibiogram, indicating that those were resistant against erythromycin, clarithromycin, clindamycin and minocycline. Pulse-field gel electrophoresis of genomic DNA digested Sma I and Apa I demonstrated homology among the isolates, which may suggest person-to-person spread in a hospital setting. With this, it is an urgent to establish the institution-based infection control precautions against S. pneumoniae.     

肺炎衣原体感染在心房颤动发病中的作用

目的探讨肺炎衣原体感染在心房颤动发病中的作用。方法44例心房颤动患者，45例健康对照，应用间接微量免疫荧光法测定血清肺炎衣原体特异性IgG、IgM抗体滴度。结果对照组与心房颤动患者肺炎衣原体总感染率分别为42％和87％，其中既往感染率分别为42％和70％，急性感染率分别为0和18％。心房颤动患者肺炎衣原体感染率显著高于对照组（P=0．002）。两组患者肺炎衣原体特异性IgM抗体均为阴性。结论心房颤动患者肺炎衣原体感染率显著高于正常对照，提示肺炎衣原体感染可能参与心房颤动的发生。     

Current concepts in the pathogenesis of meningitis caused by Streptococcus pneumoniae

In spite of improved antimicrobial therapy, bacterial meningitis still results in brain damage leading to significant long-term neurological sequelae in a substantial number of survivors, as confirmed by several recent studies. Meningitis caused by Streptococcus pneumoniae is associated with a particularly severe outcome. Experimental studies over the past few years have increased our understanding of the molecular mechanisms underlying the events that ultimately lead to brain damage during meningitis. Necrotic damage to the cerebral cortex is at least partly mediated by ischemia and oxygen radicals and therefore offers a promising target for adjunctive therapeutic intervention. Neuronal apoptosis in the hippocampus may represent the major pathological process responsible for cognitive impairment and learning disabilities in survivors. However, the mechanisms involved in causing this damage remain largely unknown. Anti-inflammatory treatment with corticosteroids aggravates hippocampal damage, thus underlining the potential shortcomings of current adjuvant strategies. In contrast, the combined inhibition of matrix metalloproteinase and tumour necrosis factor-alpha converting enzyme protected both the cortex and hippocampus in experimental meningitis, and may represent a promising new approach to adjunctive therapy. It is the hope that a more refined molecular understanding of the pathogenesis of brain damage during bacterial meningitis will lead to new adjunctive therapies.     

Cardiac device infection due to Streptococcus pneumoniae

Cardiac device infections (CDIs) are recognized complications of device implantation. Most CDIs are caused by skin flora but can also result from hematogenous seeding of the device. A case involving Streptococcus pneumoniae CDI, which is rare, potentially vaccine preventable and may not be associated with overt antecedent pneumococcal infection, is reported.     

Exploring the pathogenesis of necrotizing fasciitis due to Streptococcus pneumoniae

Monobacterial necrotizing fasciitis is a rare form of soft tissue infection usually caused by the group A beta-hemolytic Streptococcus. Soft tissue infection is an uncommon clinical manifestation of invasive disease due to Streptococcus pneumoniae. We describe 3 cases of pneumococcal necrotizing fasciitis and explore potential pathogen-specific mechanisms of pathogenesis. The clinical characteristics of necrotizing fasciitis due to S. pneumoniae and group A beta-hemolytic Streptococcus appear to overlap. The similarities include predominant occurrence in elderly adults with underlying chronic illness, predilection for lower extremity infection, progression to toxic shock-like syndrome and a high case fatality rate. No DNA fragments corresponding to speA, speB or speC were amplified by PCR from the 3 pneumococcal isolates. Western immunoblot revealed no evidence of SpeA, SpeB or SpeC protein expression. Evaluation for protease production and cytotoxicity was unrevealing. The similar clinical presentation of pneumococcal necrotizing fasciitis to the disease caused by the group A beta-hemolytic Streptococcus has important therapeutic implications. The molecular mechanisms underlying the pathogenesis are unclear. Prospective population-based studies are required to define the epidemiology of this infection.     

Penicillin insensitive and resistant Streptococcus pneumoniae infection in children

Five cases of penicillin insensitive or resistant pneumococcal infection in children were experienced during the period of 2 years since March, 1986. One isolate from middle ear showed the MIC of 4 micrograms/ml against penicillin-G. One isolate of insensitive pneumococcus was isolated from CSF specimen. Between 1976 and 1987, 59 isolates from 88 stocked pneumococcal clinical isolates were alive. These 59 strains were screened by oxacillin disc for insensitive and resistant pneumococcus. Five strains which were insensitive or resistant strains had inhibitory zone under 20 mm. The prevalence rate of insensitive or resistant pneumococcus since 1986 was 18%.     

Disseminated Streptococcus pneumoniae infection involving a ventricular assist device

We describe the first reported case, to our knowledge, of disseminated pneumococcal infection involving a left ventricular assist device (LVAD). The management of this infection was extremely challenging, requiring multiple surgical debridements, LVAD removal, and prolonged courses of antibiotics. The Streptococcus pneumoniae isolate was found to be serotype 19F, which is included in both the pneumococcal polysaccharide and conjugate vaccines. This report highlights the importance of routine screening for up‐to‐date vaccination in patients who undergo LVAD implantation.