双重实时荧光定量PCR法鉴定克柔念珠菌和光滑念珠菌

目的 建立一种快速、灵敏、特异的鉴定克柔念珠菌和光滑念珠菌的双重实时荧光定量PCR方法.方法 以核糖体基因内转录间隔区Ⅱ(ITSⅡ)为靶目标,设计并合成分别针对克柔念珠菌、光滑念珠菌的种特异引物和探针.建立双重实时荧光定量PCR反应体系,并用该体系对呼吸道相关致病菌进行检测.鉴定结果与临床常规鉴定方法对照,评价其敏感度、特异度及重复性.结果 通过对100例样品的检测,结果显示该双重实时荧光定量PCR法检测标本的鉴定结果与常规鉴定方法的结果对照,特异度为100%,敏感度为100%;最小能检测到10个拷贝数的重组质粒;批内重复实验和批间重复实验结果均与常规鉴定方法结果相符.结论 双重荧光定量PCR法鉴定克柔念珠菌和光滑念珠菌,特异度和敏感度高,重复性好,且快速、简便,该方法将有助于念珠菌病的早期诊断和针对性治疗.     

The immunodominant T helper 2 (Th2) response elicited in BALB/c mice by the Leishmania LiP2a and LiP2b acidic ribosomal proteins cannot be reverted by strong Th1 inducers

The search for disease-associated T helper 2 (Th2) Leishmania antigens and the induction of a Th1 immune response to them using defined vaccination protocols is a potential strategy to induce protection against Leishmania infection. Leishmania infantum LiP2a and LiP2b acidic ribosomal protein (P proteins) have been described as prominent antigens during human and canine visceral leishmaniasis. In this study we demonstrate that BALB/c mice infected with Leishmania major develop a Th2-like humoral response against Leishmania LiP2a and LiP2b proteins and that the same response is induced in BALB/c mice when the parasite P proteins are immunized as recombinant molecules without adjuvant. The genetic immunization of BALB/c mice with eukaryotic expression plasmids coding for these proteins was unable to redirect the Th2-like response induced by these antigens, and only the co-administration of the recombinant P proteins with CpG oligodeoxynucleotides (CpG ODN) promoted a mixed Th1/Th2 immune response. According to the preponderance of a Th2 or mixed Th1/Th2 responses elicited by the different regimens of immunization tested, no evidence of protection was observed in mice after challenge with L. major. Although alterations of the clinical outcome were not detected in mice presensitized with the P proteins, the enhanced IgG1 and interleukin (IL)-4 response against total Leishmania antigens in these mice may indicate an exacerbation of the disease.     

衣原体基因组学与蛋白组学研究进展

目前,4个种衣原体:豚鼠嗜性衣原体、鼠衣原体、沙眼衣原体和肺炎嗜性衣原体基因组已有较详细的研究,揭示了衣原体基因组的紧密性和多成员的起因。多形态膜蛋白多基因家族、具有第Ⅲ型分泌系统功能基因以及编码肽聚糖基因的发现,反映了该领域的重要研究成果。随着多个种株衣原体基因组完整核苷酸序列测定的完成,人们对衣原体发育过程中生产合成的多种蛋白的认识也在不断深入,主要包括外膜蛋白、外膜主蛋白、热休克蛋白、多态外膜蛋白等,这些蛋白的结构和功能不同,充分认识其特性对衣原体的致病机理、免疫发生机理的研究及高效基因工程疫苗的研制将会产生重要的影响。     

Nosocomial vs. community-acquired infective endocarditis in Greece: changing epidemiological profile and mortality risk

Current epidemiological trends of infective endocarditis (IE) in Greece were investigated via a prospective cohort study of all cases of IE that fulfilled the Duke criteria during 2000-2004 in 14 tertiary and six general hospitals in the metropolitan area of Athens. Demographics, clinical data and outcome were compared for nosocomial IE (NIE) and community-acquired IE (CIE). NIE accounted for 42 (21.5%) and CIE for 153 (78.5%) of 195 cases. Intravenous drug use was associated exclusively with CIE, while co-morbidities (cardiovascular disease, diabetes mellitus, chronic renal failure requiring haemodialysis and malignancies) were more frequent in the NIE group (p <0.05). Prosthetic valve endocarditis (PVE) predominated in the NIE group (p 0.006), and >50% of NIE cases had a history of vascular intervention. Coagulase-negative staphylococci and enterococci were more frequent in cases of NIE than in cases of CIE (26.2% vs. 5.2%, p <0.01, and 30.9% vs. 16.3%, p 0.05, respectively). Enterococci accounted for 19.5% of total IE cases and were the leading cause of NIE. Staphylococcus aureus IE was hospital-acquired in only 11.9% of cases. In-hospital mortality was higher for NIE than for CIE (39.5% vs. 18.6%, p 0.02). Cardiac failure (New York Heart Association grade III-IV; OR 13.3, 95% CI 4.9-36.1, p <0.001) and prosthetic valve endocarditis (OR 3.7, 95% CI 1.3-10.6, p 0.01) were the most important predictors of mortality.     

医院感染病人中段尿和血液中病原菌的种类及耐药性分析

目的了解医院感染病人中段尿和血液中分离细菌和念珠菌的种类及耐药性，为合理使用抗生素提供依据。方法大多数分离细菌的鉴定和药敏试验利用BD Phoenix仪，少数利用手工和K—B法鉴定。念珠菌利用显色平板分离和鉴定，K—B法药敏。结果分离于中段尿的1063株病原菌中最常见的是大肠埃希菌（39．6％）、粪肠球菌（9．2％）、肺炎型肺炎克雷伯菌（8．2％）、念珠菌属（11．6％）；G-杆菌中耐药率低于30％的为美洛培南、亚胺培南、头孢哌酮／舒巴坦、阿米卡星、头孢他啶和哌拉西林／他唑巴坦；G＋球菌中万古霉素和替考拉宁的敏感率均为100％：念珠菌中两性霉素B和制菌霉素的耐药率均为0，对其他药物也均低于10％。分离于血液的543株病原菌中最常见的是大肠埃希菌（16．6％）、凝固酶阴性葡萄球菌（16．4％）、铜绿假单胞菌（11．6％）、肺炎型肺炎克雷伯菌（8．3％）和金黄色葡萄球菌（7．6％）；G-杆菌中耐药率低于30％的为美洛培南、亚胺培南、头孢哌酮／舒巴坦、阿米卡星、哌拉西林／他唑巴坦、头孢他啶和氨曲南；G＋球菌中万古霉素和替考拉宁的敏感率均为100％。结论应重视对怀疑泌尿系感染和败血症的病人进行细菌真菌培养鉴定及药敏试验，以合理使用抗生素。     

Vulvovaginal candidiasis: Epidemiology,microbiology and risk factors

Abstract

Vulvovaginal candidiasis (VVC) is an infection caused by Candida species that affects millions of women every year. Although Candida albicans is the main cause of VVC, the identification of non-Candida albicans Candida (NCAC) species, especially Candida glabrata, as the cause of this infection, appears to be increasing. The development of VVC is usually attributed to the disturbance of the balance between Candida vaginal colonization and host environment by physiological or nonphysiological changes. Several host-related and behavioral risk factors have been proposed as predisposing factors for VVC. Host-related factors include pregnancy, hormone replacement, uncontrolled diabetes, immunosuppression, antibiotics, glucocorticoids use and genetic predispositions. Behavioral risk factors include use of oral contraceptives, intrauterine device, spermicides and condoms and some habits of hygiene, clothing and sexual practices. Despite a growing list of recognized risk factors, much remains to be elucidated as the role of host versus microorganisms, in inducing VVC and its recurrence. Thus, this review provides information about the current state of knowledge on the risk factors that predispose to VVC, also including a revision of the epidemiology and microbiology of VVC, as well as of Candida virulence factors associated with vaginal pathogenicity.     

Biomass Conversion: Fermentation Chemicals and Fuels

The management of invasive fungal disease (IFD) in the haemato-oncology setting remains a challenge. This article reviews recent guidelines relating to IFD for their similarities and differences, as well as applying the Appraisal of Guidelines Research and Evaluation (AGREE) criteria. The guidelines’ recommendations on antifungal prophylaxis, empirical and definitive treatment of candidiasis and aspergillosis are summarized; also, minimum standards for diagnosis and follow-up are discussed. This critique of the reviewed guidelines is a practical guide to physicians and commissioners in making local policies for IFD management.     

The epidemiology,pathogenesis, and diagnosis of vulvovaginal candidosis: A mycological perspective

Vulvovaginal candidosis (VVC) is the second most common cause of vaginitis after bacterial vaginosis, and it is diagnosed in up to 40% of women with vaginal complaints in the primary care setting. Reliable diagnosis of VVC requires a correlation of clinical features with mycological evidence. The mycological methods used for diagnosis include microscopic examination, fungal culture, and antigen tests. Fungal culture can reveal the species of organism(s) responsible for the infection and provide epidemiological data. This report reviews current knowledge about the available diagnostic methods and tests that accurately diagnose VVC, and highlights the importance of fungal culture.     

MRI confirms loss of blood–brain barrier integrity in a mouse model of disseminated candidiasis

Disseminated candidiasis primarily targets the kidneys and brain in mice and humans. Damage to these critical organs leads to the high mortality associated with such infections, and invasion across the blood–brain barrier can result in fungal meningoencephalitis. Candida albicans can penetrate a brain endothelial cell barrier in vitro through transcellular migration, but this mechanism has not been confirmed in vivo. MRI using the extracellular vascular contrast agent gadolinium diethylenetriaminepentaacetic acid demonstrated that integrity of the blood–brain barrier is lost during C. albicans invasion. Intravital two‐photon laser scanning microscopy was used to provide the first real‐time demonstration of C. albicans colonizing the living brain, where both yeast and filamentous forms of the pathogen were found. Furthermore, we adapted a previously described method utilizing MRI to monitor inflammatory cell recruitment into infected tissues in mice. Macrophages and other phagocytes were visualized in kidney and brain by the administration of ultrasmall iron oxide particles. In addition to obtaining new insights into the passage of C. albicans across the brain microvasculature, these imaging methods provide useful tools to study further the pathogenesis of C. albicans infections, to define the roles of Candida virulence genes in kidney versus brain infection and to assess new therapeutic measures for drug development. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.     

THE PROTECTIVE IMMUNE RESPONSE AGAINST VAGINAL CANDIDIASIS: LESSONS LEARNED FROM CLINICAL STUDIES AND ANIMAL MODELS

Recurrent vulvovaginal candidiasis (RVVC) is a significant problem in women of childbearing ages and is caused by Candida albicans, a commensal organism of the intestinal and reproductive tracts. As a result of this commensalism, most healthy individuals have demonstrable Candida -specific adaptive immunity that is considered protective. In women with RVVC, a deficiency/dysfunction of this protective immunity is postulated to affect susceptibility to infection. Although cell-mediated immunity (CMI) is considered important for protection against mucosal candidal infections, little is understood about specific host defenses that are important at the vaginal mucosa. Studies to date suggest that a compartmentalized local, rather than systemic, immunity is important for defense against vaginitis. This review will summarize the current state of knowledge regarding protective host defense mechanisms against vaginal C. albicans infections both from clinical studies and animal models. From these data, hypotheses are presented for what host defense mechanisms appear important for resistance/susceptibility to vaginal infection.