烟曲霉提取物诱导小鼠哮喘模型的建立

目的:探讨小鼠哮喘模型建立的方法,为开展哮喘发生机制或药物治疗研究奠定基础。方法:40只,SPF级C57BL/6小鼠,雌雄各20只,随机分成对照组和模型组两组。模型组小鼠采用气管滴注烟曲霉提取物,隔天给药,对照组小鼠采用无菌0.9%氯化钠溶液气管滴注。给药21天后,最后一次给药24小时后收取肺泡灌洗液,离心后灌洗液上清检测炎症因子水平,灌洗细胞做Giemsa染色分类计数;取左肺做AB-PAS染色,右肺提取mRNA;腹主动脉取血ELISA检测Ig E水平。结果:与对照组相比,模型组小鼠可见典型的哮喘症状,肺泡灌洗液中炎症细胞总数、嗜酸性粒细胞和中性粒细胞较对照组显著增多,肺泡灌洗液IL-3、IL-4、IL-5、IL-6及IL-17表达上调,与对照组相比分别为P<0.05和P<0.01。血清Ig E较对照组明显增加[(23.84±3.65)vs.(6.22±1.06)mg/L,P<0.01];AB-PAS染色黏液分泌较对照组明显加重。结论:烟曲霉提取物气管滴注可成功诱导小鼠哮喘模型。     

Sequencing the Aspergillus fumigatus genome

Aspergillus fumigatus is the most common mould pathogen of human beings and unusually causes both invasive disease in immunocompromised patients and allergic disease in patients with atopic immune systems. 4% of patients dying in modern European teaching hospitals have invasive aspergillosis and it is the leading infectious cause of death in leukaemia and bone marrow transplant patients. Until 2001, only two licensed antifungal drugs were available to treat aspergillosis-amphotericin B and itraconazole. Its 28-30Mb genome is being sequenced in an international collaboration, with the Wellcome Trust Sanger Institute (UK) and The Institute for Genomic Research (TIGR, USA) as the two main centres. A whole-genome shotgun approach was adopted and initiated in 2001 with an expected completion date in 2003. The complete sequence will permit identification of pathways specific to pathogenic Aspergillus species, help identify new targets for antifungal drugs, and enable investigations into the basic biology of fungi. Numerous secondary metabolic pathways with biotechnological applications and pharmacological properties are found in the Aspergilli and the genome sequence will facilitate research in this area.     

TLR2对曲霉感染支气管上皮细胞时Dectin-1表达的影响

目的 探讨烟曲霉感染人支气管上皮（HBE）细胞时Toll样受体2（TLR2）对树突状细胞植物血凝素-1 （Dectin-1）表达的影响.方法 建立烟曲霉感染HBE细胞模型,通过PCR、Western blot方法分别在mRNA、蛋白水平检测Dectin-1和TLR2的表达情况;沉默TLR2,复制感染模型,应用Western blot及流式细胞技术评价Dectin-1的表达变化.结果 ①烟曲霉感染后HBE细胞TLR2表达水平虽然有所升高,并在感染18h达到峰值,但与静息状态表达水平的差异无统计学意义（P＞0.05）.②沉默TLR2,在烟曲霉感染HBE细胞后18 h时Dectiin1的蛋白表达受到显著抑制（P＜0.05）.结论 HBE细胞静息状态下能够表达TLR2,在烟曲霉感染早期,随着时间的延长其表达有逐步增高的趋势;HBE细胞启动Dectin-1的表达可能是建立在TLR2对烟曲霉早期识别的基础上,通过下游信号通路的激活来实现的。     

Pacemaker lead infection caused by Aspergillus fumigatus

We report a case of pacemaker lead infection caused by Aspergillus fumigatus that was successfully treated by surgery and with voriconazole. This infection is rare and dangerous. When it is suspected, transesophageal echocardiography should be performed to look for lead-attached vegetations and the entire pacing system should be removed.     

烟曲霉致病相关因子的研究进展

毒力因子是在病原体适应生存环境的过程中产生.烟曲霉毒力是多因素相关的,包括微小的孢子结构使之能够吸入到达宿主的肺泡,耐热特征,疏水性,快速的繁殖速度以及抵抗氧化应激反应的能力.此外,烟曲霉适应环境及代谢相关的蛋白、通路信号分子、脂类代谢产物、毒素等均可看作毒力因子.     

Fractionation of culture filtrate antigens of Aspergillus fumigatus

Polyacrylamide disc gel electrophoresis (PAGE) and two-dimensional crossed immunoelectrophoresis (2D-CIE) of crude culture filtrate antigens prepared from three clinical isolates of Aspergillus fumigatus revealed a striking similarity in the number and nature of their antigenic components, notwithstanding the wide differences in their total protein contents. The antigenic components, which are largely proteins and glycoproteins, varied from 9-10 in number depending on the isolate. A prominent glycoprotein band, common to all the three isolates, merits further purification and detailed study. The serodiagnostic value of culture filtrate antigens of A. fumigatus vis-a-vis mycelial antigens, has been discussed.     

Allergenic components of Aspergillus fumigatus determined by radioimmunoprecipitation

The allergenic components of Aspergillus fumigatus were identified using radioimmunoprecipitation (RIP) assay. Sera from 20 asthmatic children with positive skin tests to A. fumigatus were used for assay. Immune complexes formed between iodinated A. fumigatus and IgE antibodies in patients' sera were precipitated by immobilized anti-IgE monoclonal antibodies (MAbs). The precipitates were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and analyzed by autoradiography. It was found that IgE antibodies in the sera of allergic individuals reacted with several allergenic components of A. fumigatus ranging from 10 to 125 kD. Proteins of 38, 33, and 68 kD were recognized by IgEs from the allergic sera with frequencies of 85%, 65%, and 40%, respectively. It appears that these are the major allergenic components of A. fumigatus.     

烟曲霉识别分子研究进展

细胞识别分子是近年来研究烟曲霉发病机制的重要内容,Toll样受体以及Dectin-1等模式识别相关受体是研究热点,通过对烟曲霉的识别参与免疫效应细胞的吞噬及杀伤过程,在机体抵抗真菌感染中发挥着极其重要的作用.     

Factors effecting impact of Aspergillus fumigatus sensitization in cystic fibrosis

The clinical impact of Aspergillus fumigatus (Af) sensitization in cystic fibrosis (CF) is controversial. We examined the effect of Af sensitization (Afs) on pulmonary function and growth using a retrospective cohort analysis over two 5-year study periods: 1996-2000 (19 Afs cases and 19 controls) and 2001-2005 (24 Afs cases and 23 controls). Sensitization was defined as Af specific radioallergosorbent test (RAST) >or= 17.5 iu/ml and total serum IgE level >or=150 iu/ml. We examined the impact of changing treatment schedules over these periods. Afs cases had lower median FEV(1) %predicted (%PR) compared to matched controls 1996: 67 versus 80, P < 0.01; 2001: 78 versus 93, P < 0.01. Afs cases in the 2001 cohort had a higher FEV(1) %PR compared to Afs cases in the 1996 cohort: 78 versus 67, P < 0.01. For the 1996 Afs cohort FEV(1) %PR fell significantly over 5 years but not for the 2001 Afs cohort. Af RAST and total IgE reflected the changes in pulmonary function. Children in the 2001 Afs cohort were prescribed significantly more oral antifungal treatment (odds ratio 4.3, 95%CI 1.2-15.7, P = 0.03). Afs children continue to have poorer lung function compared to controls but this observational, hypothesis generating study, suggests that the use of antifungal treatment is associated with better lung function.     

Inhibition of complement by culture supernatants of Aspergillus fumigatus

Aspergillus fumigatus produced a water-soluble extracellular material that inhibited the opsonization of fungal cells by normal human serum. Blastospores of Cryptococcus neoformans and conidia from A. fumigatus or Aspergillus niger were used as fungal targets for ingestion by human monocytes. The opsonic inhibitor from A. fumigatus was found to decrease binding of complement component C3b to fungal surfaces by selectively interfering with activation of the alternative complement pathway. Inhibition of complement did not appear to result simply from proteolysis, as judged by the minimal degradation of casein and of purified C3 and C4. The complement-inhibiting activity was partially labile to heating at 100 C and could be concentrated by using dialysis tubing with a 10,000-dalton exclusion limit. Aspergillus flavus, which is also a pathogen for humans, also produced this activity; A. niger did not. We speculate that this material may represent a pathogenesis factor for Aspergillus species.     

Short-term curative treatment of Aspergillus fumigatus pneumonia with fluconazole

A 67-year-old previously healthy female presented with fever, malaise and bilateral pulmonary infiltrates. Serology and culture were positive for Aspergillus fumigatus. After 15 days of treatment with fluconazole, clinical cure and regression of the infiltrates were obtained. No side-effects were observed during or after treatment.     

The isolation and evaluation of Aspergillus fumigatus antigens]

Antigens from three strains of Aspergillus fumigatus (354, 356, and JIG) and an antiserum against the mixing of these antigens have been produced, and evaluated immunochemically. The antigens were obtained through a modified Coleman & Kaufman technique (culture filtrate concentrated by acetone). Analysis by the immunodiffusion test (ID) against homologous serum has yielded 100% sensitivity (with the studied sera). Concerning heterologous sera we found reactivity with a serum of a patient of candidiasis and another with histoplasmosis. The same result was obtained with a reference antigen in immunodiffusion, showing similar standards of response. Titration of the antiserum by ID and counterimmunoelectrophoresis showed a title of 1:32, and by complement fixation (micro-technique) a title of 1:128. Using immunoelectrophoresis (IEF), the produced antiserum yielded 8 lines of precipitation (5 in the anodic pole and 3 in the cathodic one). In SDS-PAGE at 12.5% the antigen has presented a rather complex electrophoretic profile (26 proteic subunits with a molecular weight ranging from 18 a > 100 kDa). Immunogenicity of the antigen was observed in all fractions of SDS-PAGE when the immunoblotting against the antiserum was carried out.     

Aspergillus fumigatus endocarditis in a patient with a biventricular pacemaker

Aspergillus fumigatus endocarditis is one of the rarest and severest complications in cardiological patients. We describe a patient with an intracardial pacemaker who was diagnosed as having Aspergillus fumigatus endocarditis. Postmortem examination showed a large, Aspergillus-infected thrombus encased in the right ventricle, pulmonary trunk and main pulmonary branches.     

Treatment of postoperative Aspergillus fumigatus spondylodiscitis with itraconazole.

A 46-year-old man presented with Aspergillus fumigatus spondylodiscitis after lumbar surgery. He was successfully treated with the new antifungal drug itraconazole in combination with surgical débridement of the disc space. The patient has remained on itraconazole for more than a year and tolerated the drug well.     

Aspergillus fumigatus epidural abscess in a renal transplant recipient.

An epidural abscess caused by Aspergillus fumigatus occurred in a recipient of a cadaveric, renal allograft. The patient had persistent back pain and a peripheral neuropathy that involved the lower extremities. Signs of spinal cord compression evolved. No definite portal of entry was found. Diagnosis was made by histologic examination and culture of a biopsy specimen. Therapy, consisting of aggressive surgical debridement, intravenous amphotericin B, and oral flucytosine was unsuccessful in eradicating the organism. At postmortem examination, Aspergillus was identified at the abscess site. To our knowledge, aspergillosis presenting as an epidural abscess in the immunosuppressed, renal transplant recipient has not previously been reported and should be considered in the differential diagnosis of back pain and peripheral neuropathy in such a patient.