C3aR拮抗剂治疗PR8/MRSA共感染小鼠肺炎损伤的研究

目的 补体异常激活可大量产生过敏毒素C3a分子,通过利用C3aR受体拮抗剂(C3aRa)可抑制C3a功能,达到治疗流感病毒和金黄色葡萄球菌(PR8/MRSA)共感染小鼠肺炎损伤的目的 ,探究一种治疗共感染重症肺炎损伤的新策略.方法 PR8/MRSA共感染小鼠尾静脉注射C3aR受体拮抗剂C3aRa,剂量1 mg/kg,1次/2 d,观察记录小鼠死亡率变化;测量共感染小鼠体质量,取新鲜肺组织称重,计算肺指数;制备小鼠肺组织石蜡切片并行HE染色,观察肺部病理改变.结果 经过敏毒素受体拮抗剂C3aRa干预后的共感染小鼠较对照组生存率提高了30％,肺组织充血、水肿和出血程度减轻,肺指数明显下降(P＜0.001).结论 C3aRa在流感/细菌共感染重症肺炎的治疗中具有一定疗效,为临床利用补体干预治疗共感染重症肺炎提供了一种新策略.     

甲型H1N1流感影像学研究现状及相关问题

甲型H1N1流感为急性呼吸道传染病,其病原为甲型H1N1流感病毒,患者病情发展迅速,常因发生初级病毒性肺炎,而进一步发生呼吸窘迫综合征,也可发生甲型流感脑病、多器官损伤衰竭而死亡。在死亡病例中以有基础疾病、肥胖及孕产妇等发生合并症者为多。了解甲型H1N1流感肺炎及甲型流感脑病的早期影像学特点,早期诊断和适当的干预治疗,及时准确的影像学检查与科学评价对危重并发症的发生、病情预后、降低病死率等具有重大意义。     

金黄色葡萄球菌败血症的病原治疗

金葡菌败血症的治疗,包括三个方面,即金葡菌败血症本身的治疗、原发病灶的治疗和金葡菌败血症迁徙性病灶的治疗。而金葡菌败血症本身的治疗,除对症治疗(如败血症休克的治疗等)与支持治疗(如对免疫缺陷的治疗)外,重点是病原治疗。考虑到当前金葡菌对抗菌药物的耐药现状,病原治疗又必须依不同情况采用不同的方案。1　不产青霉素酶金葡菌引起的败血症　　首选青霉素G或氨苄西林,有时(如对青霉素过敏)可选红霉素、磷霉素或头孢唑啉替代。青霉素G为杀菌剂,用量为400万U,1次/4～6h,静滴,30min后即达血药浓度峰值,并迅速分布全身。氨苄西林对金葡…     

肽抗生素hPAB-β抗金黄色葡萄球菌L型活性分析

目的 观察毕赤酵母高密度发酵表达的肽抗生素hPAB-β对L型细菌的抗菌活性.方法 采用新青Ⅱ纸片扩散法诱导金黄色葡萄球菌标准株ATCC25923 L型,通过形态学观察、滤过实验、回复实验以及电镜观察鉴定L型菌;采用酵母高密度发酵制备肽抗生素hPAB-β,通过稀释法检测hPAB-β对L型细菌的抗菌活性并测定其最小抑菌浓度(MIC).结果 用新青Ⅱ可成功诱导金黄色葡萄球菌L型;所得L型菌能通过0.45μm的滤膜;撤去抗生素后,L型能回复为野生菌;电镜下见多数金葡菌L型的细胞壁部分缺失,少数完全缺失;稀释法检测显示hPAB-β对金葡菌L型具有良好的抗菌活性,其MIC值为32μmol/L.结论 肽抗生素hPAB-β对金葡菌L型有良好的抗菌活性.     

金黄色葡萄球菌性肺炎

金葡菌肺炎是由金葡菌引起的急性化脓性肺部感染。常发生于机体免疫功能受损的病人,病情严重,病死率高,占医院外获得性肺炎的5%以下,医院内肺炎中至少有10%为金葡菌引起。1　发病机制　　金葡菌常寄生于皮肤、鼻咽部,约15%～30%的健康人有一过性带菌,医院某些科室工作人员的带菌率可达50%以上。当机体抵抗力下降或局部防御机能被破坏时,金葡菌侵入局部组织或血液循环并大量繁殖,引起临床感染。金葡菌的致病物质主要是毒素和酶。金葡菌依仗溶血毒素、杀白细胞素、表皮剥脱素、肠毒素和中毒性休克综合征型毒素等及血浆凝固酶、溶纤维蛋白酶、…     

金黄色葡萄球菌败血症的发病机制

侵入人体的金葡菌是否引起败血症,取决于人体和细菌这一对矛盾之间的力量对比。少量金葡菌进入血液循环形成一过性菌血症为常见现象,抠挤疖肿、拔牙、扁桃腺摘除术等尤易发生此种情况。一过性菌血症在健康人体一般不足为害,侵入的少量金葡菌可迅速被吞噬细胞所吞噬而清除,或被血清备解素、溶菌酶、补体、调整素等非特异性杀菌防御因子所杀灭。然而,金葡菌的侵袭力是很强的,97%的菌株具有血浆凝固酶,可使加有抗凝剂的人血浆发生凝固。金葡菌感染机体后释放血浆凝固酶,在菌体周围筑起一道纤维蛋白保护层,从而使其免受血清中杀菌物质的杀伤,也…     

金葡菌败血症早期诊断和治疗的体会

败血症是内科常见病,诊断一般不难,但金葡菌败血症病情复杂,易发生迁徙,引起一个或多个脏器受侵犯,以致掩盖其本质。本病死亡率较高,约为20％左右。为达到早期诊断的目的,现将我们近年来遇到的病情较为复杂的金葡菌败血症的诊断治疗,结合我们的体会举例讨论如下。 一、以腰痛、腹胀为主要表现,颇似急性胰腺炎或肾周脓肿:     

甲型H1N1流感病毒抗原表位区段的克隆和表达

据统计,全世界每年流感流行都会造成10％～20％的人感染流感病毒,给整个社会带来极大的经济负担。2009年4月在墨西哥、美国暴发的甲型H1N1流感,其病毒是一种与猪流感病毒高度同源的新型变异毒株,它包含禽流感、猪流感和人流感3种流感病毒的基因片段,同时拥有亚洲猪流感病毒和非洲猪流感病毒的特征,是一种“杂交型”流感病毒。与传统的猪流感病毒不同,该病毒能在人和人之间快速传播。到目前为止,全球40多个国家均发现有甲型H1N1流感病毒感染的存在,国内外高度关注该病毒诊断试剂和疫苗的研制。     

川西某部A3型流感抗体免疫水平调查

流行性感冒是军营常见的传染病,当机体感染流感病毒后,起主导保护作用的是血凝素抗体,血凝素抗体具有亚型和株的特异性。流感病毒抗原发生变异,机体可随着变异逐渐失去保护作用。为了进一步了解川西片区驻军人群对流感病毒的免疫水平,病毒流行趋势,1997～1998年我们分别对驻川西某部进行了流感抗体水平检测,现报告如下。     

非典型肺炎患者的临床表现分析

目的 探讨非典型肺炎的流行病学特征、临床表现、实验室检查和X线检查的特征、鉴别诊断要点和治疗方法。方法 回顾性研究2003年2月至4月的非典型肺炎患者和可疑患者的流行病学特征和临床表现,鉴别诊断和疗效。结果社会交往频繁的人员发病率高,临床表现为急起发热、全身中毒症状.无上呼吸道卡他症状,干咳,肺部体征不明显,外周血白细胞数不高甚至降低,淋巴细胞减少,血沉增快,X线胸片均有浸润性改变。易误诊为流感、流感病毒性肺炎、禽流感、支原体肺炎和肺结核。以抗病毒药、抗细菌药、糖皮质激素和免疫调节为主的综合治疗措施疗效较好。结论 非典型肺炎是由冠状病毒亚型变种引起的急性呼吸道传染病,以发热、干咳、全身中毒症状、外周血白细胞不高,胸片有浸润性阴影为主要临床表现,特别注意与流感和流感病毒性肺炎鉴别,治疗上应采取综合疗法。     

A sudden death due to acute necrotizing encephalopathy associated with influenza A virus infection: An autopsy case report

Influenza occasionally causes central nervous system disorders. Acute necrotizing encephalopathy (ANE) is one of the most severe influenza-associated complications, predominantly affecting infants and young children under 5 years of age. We present this case as it involves a very rare complication of influenza infection that is known to have a high rate of mortality. A 5-year-old girl presented with a high fever and convulsions. Her condition deteriorated rapidly, and she died within 24 h. Autopsy revealed extensive brain edema, multifocal perivascular hemorrhage, and necrosis of neurons without inflammatory cell infiltration in the pons and bilateral thalamus. Tests for influenza virus A and antibodies to it were positive. The girl’s death was attributed to ANE associated with influenza A infection based on the clinical presentation, the postmortem neuropathology, and identification of the virus. The goal of this report is to draw attention to the potentially serious complications of influenza A infection. We hope that the lethal outcome of this disease will be fully recognized by medical personnel.     

慢性肾衰病人感染并发症的防治

感染是慢性肾衰（CRF）病人常见而严重的并发症,是导致CRF病人高死亡率的主要原因。目前越来越多证据表明,适当的预防治疗可明显降低CRF病人某些感染并发症的发生率,如结核感染、金黄色葡萄球菌感染和肝炎病毒引起的肝脏病变。研究并制定防治CRF各种感染并发症的措施仍是临床肾脏病学者肩负的重要任务。     

A comparative study of thin-section CT findings between seasonal influenza virus pneumonia and Streptococcus pneumoniae pneumonia

Objective:

To compare the pulmonary thin-section CT findings in patients with seasonal influenza virus pneumonia with Streptococcus pneumoniae pneumonia.

Methods:

The study group included 30 patients (20 males and 10 females; age range, 20–91 years; mean age, 55.9 years) with seasonal influenza virus pneumonia and 71 patients (47 males and 24 females; age range, 27–92 years; mean age, 67.5 years) with S. pneumoniae pneumonia.

Results:

The proportion of community-acquired infection was significantly higher in patients with influenza virus pneumonia than with S. pneumoniae pneumonia (p = 0.001). CT findings of ground-glass attenuation (GGA) (p = 0.012) and crazy-paving appearance (p = 0.03) were significantly more frequent in patients with influenza virus pneumonia than with S. pneumoniae pneumonia. Conversely, consolidation (p < 0.001), mucoid impaction (p < 0.001), centrilobular nodules (p = 0.04) and pleural effusion (p = 0.003) were significantly more frequent in patients with S. pneumoniae pneumonia than in those with influenza virus pneumonia.

Conclusion:

Pulmonary thin-section CT findings, such as consolidation and mucoid impaction may be useful in distinguishing between seasonal influenza virus pneumonia and S. pneumoniae pneumonia.

Advances in knowledge:

(1) Distinguishing seasonal influenza virus pneumonia with S. pneumoniae pneumonia is important. (2) The CT findings of GGA and crazy-paving appearance were more frequently found in patients with influenza virus pneumonia than in patients with S. pneumoniae pneumonia, whereas consolidation, mucoid impaction, centrilobular nodules and pleural effusion were more frequently found in patients with S. pneumoniae pneumonia.Influenza virus is responsible for seasonal epidemics of community-acquired pneumonia (CAP), with outbreaks occurring predominantly during the winter months. Secondary bacterial superinfections are the most frequent complications among fatal cases of seasonal and pandemic influenza.Streptococcus pneumoniae is the most common pathogen of CAP and is also responsible for the increasing frequency of nosocomial pneumonia.^1–3 The mortality related with pneumonia is affected by initial antibiotic therapy; therefore, early detection of S. pneumoniae pneumonia is important for reducing mortality. Moreover, S. pneumoniae has been identified as the most prominent causative agent for secondary bacterial pneumonia following influenza virus infection.⁴A rapid immunochromatographic membrane test was developed for the detection of S. pneumoniae antigens.⁵ It is a useful technique for the rapid diagnosis of S. pneumoniae pneumonia; however, it does have its limitations. For example, urinary antigens of S. pneumoniae pneumonia cannot be detected a few days after S. pneumoniae infection, and assay sensitivity is approximately 70–80%.There are several reports of the radiologic features of novel influenza virus pneumonia and S. pneumoniae pneumonia.^6–8 However, there are few reports of the CT findings of seasonal influenza virus pneumonia.^9–11 Furthermore, to the best of our knowledge, no studies comparing CT findings in patients with seasonal influenza virus pneumonia to those with S. pneumoniae pneumonia have been published. The present study therefore compared the pulmonary thin-section CT findings of patients with seasonal influenza virus pneumonia to those with S. pneumoniae pneumonia.     

急性重症脑卒中患者并发院内获得性肺炎的病原菌分布及耐药性分析

目的了解医院急性重症脑卒中患者并发院内获得性肺炎（hospital acquived peneumonia,HAP）的病原菌分布及耐药性,以指导临床抗生素的合理使用。方法回顾分析湖北省武汉市第一医院神经内科重症监护病房自2011年1月—2012年5月收治的225例急性重症脑卒中并发HAP患者的临床资料。结果在225例患者中分离出11种共121株致病菌,其中以革兰阴性杆菌为主,占68.60%,主要为铜绿假单胞菌、大肠埃希菌、鲍曼不动杆菌等;革兰阳性菌占29.75%,主要为金黄色葡萄球菌;真菌占1.65%,为白假丝酵母菌。鲍曼不动杆菌和铜绿假单胞菌的耐药率高,对碳青霉烯类抗生素已分别产生了78.4%、83.3%的耐药率,而大肠埃希菌和肺炎克雷伯菌对碳青霉烯类抗生素保持了100%的敏感性,金黄色葡萄球菌对青霉素类抗生素的耐药率达90%以上,但尚未发现对万古霉素的耐药菌株。结论急性重症脑卒中患者并发HAP的主要致病菌为革兰阴性菌。这些主要致病菌多为条件致病菌,且都有很强的耐药性。因此临床上应结合药敏试验科学合理用药,神经内科重症监护病房加强监测与控制,以期快速治愈患者。     

大流行甲型H1N1流感病毒变异株的小鼠感染实验研究

目的对甲型H1N1流感病毒变异株的小鼠感染特征进行观察。方法经过体外鸡胚/MDCK细胞传代和筛选,获得1株甲型H1N1流感病毒变异株（vCA07）;使用不同剂量流感病毒滴鼻感染BALB/c小鼠后,计算半数致死量和半数感染量,观察小鼠感染后的体质量变化、肺部病毒增殖、肺部组织病理变化等。结果与野生型毒株相比,甲型H1N1流感病毒变异株对BALB/c小鼠的致病性显著提高,其可在小鼠肺组织中高效增殖,并导致显著的病理损伤。结论甲型H1N1流感病毒变异株感染特征得以明确,为进一步建立高致病性甲型H1N1流感病毒的小鼠感染模型以及大流行甲型H1N1流感病毒致病机制的研究奠定了基础。     

Identification of Staphylococcus aureus brain abscesses: rat and human studies with 1H MR spectroscopy

PURPOSE: To determine the feasibility of a statistical classification strategy (SCS) and the identity of metabolites of bacterial and host origins that potentially contributed to the most discriminatory regions of magnetic resonance (MR) spectra from Staphylococcus aureus abscesses of biopsy material from controls, gliomas, and staphylococcal abscesses. MATERIALS AND METHODS: Human and animal study received ethics committee approval, and informed patient consent was obtained. A rat model of S aureus brain abscess was developed. Histologic and microbiologic examination was performed to assess abscess development 3-4, 6-8, and 10-15 days after initiation. Metabolite profiles in pus (n = 62) and controls (n = 37) were characterized with ex vivo MR spectroscopy and compared with data from rat gliomas (n = 27). SCS, optimal region selection, and development of pairwise classifiers allowed MR spectra of abscesses (n = 42, day 6-8) to be distinguished from those of glioblastoma multiforme and controls. MR spectroscopy profiles of pus from animal abscesses were compared with in vivo MR spectra from patients with staphylococcal brain abscesses (n = 7, aged 6-67 years) and ex vivo pus MR spectra from patients with S aureus abscesses. RESULTS: Histologically confirmed abscesses were present 6-8 days after stereotactic injection of S aureus in 42 of 47 rats (89%). MR spectra of abscesses and glioblastoma multiforme in the animal model were similar. Typical metabolites of abscesses due to anaerobe bacteria (acetate, succinate, amino acids) were not detectable in S aureus abscesses in rats or humans. MR spectroscopic findings from controls, abscesses, and gliomas were distinguished by means of SCS with an accuracy of 99%. Analysis of the most discriminatory regions with two-dimensional correlation spectra indicated that glutamine and/or glutamate and aspartate potentially contributed to successful classification. CONCLUSION: S aureus is detectable in abscesses with a non-culture-based method in an animal model.     

一株新型甲型H1N1流感病毒H275Y的奥司他韦耐药变异分析

目的 探讨2009年新型甲型H1N1流感病毒神经氨酸酶(NA)基因的进化规律,分析NA蛋白酶活性位点以及糖基化位点变化情况.方法 从NCBI检索获得110株不同年代、不同地域甲型流感病毒NA基因序列,用MEGA 4.0软件进行基因进化分析,并用NJ法构建进化树;对NA基因核苷酸序列同源性及编码蛋白氨基酸序列进行分析.结果 2009年新型甲型H1N1流感病毒世界各地不同毒株间的NA基因同源性极高,达到99.5%～100%,但与以往甲型H1N1人流感病毒的NA基因差异较大.2009年新型甲型H1N1流感病毒与欧洲A/swine/H1N1的NA基因同源性高,达到89.6%～92.9%,且糖基化位点分布一致,分别在50、58、63、68、88、146、235和386位存在糖基化现象.另外2009年新型甲型H1N1流感病毒与A/chicken/H5N1的NA基因同源性也较高,达到83.6%～85.3%.绝大部分2009年新型甲型H1N1流感病毒的NA蛋白酶活性中心及周围相关位点氨基酸组成保守,仍然表现为R118、D151、R152、R225、E277、R293、R368、Y402、E119、R156、W179、S180,D199、1223、E228、H275、E278、N295和FA25,但丹麦、日本、我国香港及湖南分离到的4株病毒出现H275Y突变.2009年新型甲型H1N1流感病毒NA基因可能来源于欧洲A/swine/H1N1流感病毒,并与A/chicken/H5N1病毒有较近的亲缘关系.结论 2009年新型甲型H1N1流感病毒并非由以往人H1N1流感病毒逐渐进化而来,而是一种新型重排病毒,我国湖南地区发现的一株新型甲型H1N1流感病毒具有H275Y奥司他韦耐药变异.     

MEBO对生长繁殖8h细菌的作用

目的：观察MEBO对生长繁殖8h的细菌的作用。方法：将细菌（变形杆菌，大肠杆菌，绿脓杆菌，金黄色葡萄球菌）接种在琼脂培养基上，置37℃培养8h，取出于接种细菌的表面涂抹上MEBO继续置37℃培养。分别于培养3h,5h,7h,9-10h取出涂片观察。结果：MEBO对生长繁殖8h的细菌除葡萄球菌的形态基本同原菌外，其余三种细菌都于3h就观察长短不等的杆菌。于9－10h都呈现小球杆菌。而在整个培养过程中未见到长丝状变异。结论：MEBO对处于生长繁殖期的细菌有显的抗菌作用。     

Binding of 99mTc-labelled polyclonal human immunoglobulin to bacteria as a mechanism for scintigraphic detection of infection

The aim of the present study was to determine whether 99mTc-labelled polyclonal human immunoglobulin (99mTc-HIG) binds to bacteria in vitro as well as in vivo. In vitro, the binding of 99mTc-HIG to various gram-positive and gram-negative bacteria was determined. In vivo, mice were infected with Staphylococcus aureus Cowan I (protein A rich) or S. aureus EMS (protein A deficient) in a thigh muscle and then 99mTc-HIG or 99mTc-labelled human serum albumin (99mTc-HSA) was administered; scintigrams were made 1, 4, and 18 h later. In vitro binding of 99mTc-HIG to bacteria was higher for gram-positive than for gram-negative forms. A positive correlation was found between the protein A content and the degree of binding to S. aureus. This was also found in vivo. The accumulation of 99mTc-HIG at the site of infection was significantly (P less than 0.01) higher than that of 99mTc-HSA, for both strains of S. aureus. It is concluded that vascular permeability cannot fully explain the accumulation of 99mTc-HIG at the site of infection and that binding of 99mTc-HIG to bacteria plays a role in this respect.     

某舰微环境和空气细菌调查与分析

目的了解舰艇内部环境温湿度和空气微生物浓度及种类,发现导致舰艇官兵呼吸道疾病高发的可能致病因素。方法采用数字温湿度计测量舰艇内部环境温度和湿度;平皿暴露法采集舰艇内部空气细菌,平板划线接种分离纯化出细菌纯培养物,使用革兰染色、细胞镜检和16S rDNA测序等细菌鉴定方法鉴定细菌种类。结果气温符合标准要求的调查点占20%,相对湿度符合率为100%;采样当天舰艇内部空气细菌浓度不高,但细菌种类多样,分离出济州金黄杆菌、鲍曼不动杆菌、耐热芽孢杆菌、金黄色葡萄球菌、头部葡萄球菌、人葡萄球菌人亚种、人耐新生霉素败血亚种、科恩葡糖球菌科恩亚种和解脲亚种、空气滤器水栖菌、干酪乳杆菌、溶酪大球菌、产氨棒杆菌、短芽孢杆菌、丛毛单胞菌、枯草芽孢杆菌、矢野口鞘氨醇杆菌、人金黄杆菌18株不同种或亚种的细菌。结论舰艇官兵呼吸道疾病高发可能与舰艇内部气温偏低及空气中某些细菌存在有关。