慢性烟曲霉暴露对支气管哮喘大鼠气道黏蛋白MUC5AC表达的影响

[目的]探讨慢性烟曲霉暴露对支气管哮喘(简称哮喘)大鼠气道黏蛋白MUC5AC表达的影响.[方法]将56只雄性Wistar大鼠按随机数字表法分为7组(每组8只):慢性哮喘(A)组、慢性哮喘+烟曲霉孢子吸入1周(B)、3周(C)和5周(D)组、慢性哮喘+生理盐水吸入(E)组、卵清白蛋白(OVA)致敏生理盐水激发(F)组和OVA致敏生理盐水激发+烟曲霉孢子吸入(G)组.测定各组大鼠基础气道阻力和应用乙酰胆碱后气道阻力变化率,RT-PCR测定肺组织MUC5AC mRNA的表达,免疫组织化学染色测定各组大鼠气道上皮细胞MUC5AC的表达,酶联免疫吸附(ELISA)法测定BALF中IL-13水平,肺组织切片过碘酸雪夫染色(PAS)观察气道上皮杯状细胞增生程度.[结果]B、C和D组大鼠肺组织MUC5AC mRNA(MUC5AC mRNA/β-actin mRNA)(分别为1.9±0.4、2.3±0.6、2.9±0.8)、气道上皮细胞MUC5AC表达(A值)(分别为278±58、566±64、891±80)、BALF上清液IL-13[分别为(96±16)、(136±22)、(197±34)μg/L]及杯状细胞/上皮细胞面积(分别为16％±5％、23％±7％、36％±9％)均高于A、E、F及G组(均P＜0.05);C和D组大鼠气道阻力变化率(分别为61.91％±5.26％、84.69％±6.38％)均高于A、E、F及G组(均P＜0.05).B、C和D组哮喘大鼠MUC5AC的A值及MUC5AC Mma/β-actin mRNA与气道上皮杯状细胞增生程度(PAS染色区面积/上皮细胞面积)呈正相关(r值分别为0.578和0.614,均P＜0.05),与气道反应性(Raw变化率)呈正相关(r值分别为0.638和0.564,均P＜0.05).[结论]慢性烟曲霉暴露可上调哮喘大鼠气道上皮黏蛋白MUC5AC的表达,促进杯状细胞增生,加重气道高反应.     

卡泊芬净治疗心脏术后侵袭性真菌病20例临床分析

目的:探讨卡泊芬净治疗心脏术后并发侵袭性真菌感染(IFI)的疗效与安全性。方法:回顾分析我院呼吸科、心外科和急诊重症监护室(ICU),接受过卡泊芬净治疗的心脏术后合并IFI患者临床资料。结果:2005年5月至2010年12月,共有20例接受了卡泊芬净治疗。男性12例,女性8例,中位年龄65岁(23～82)岁。确诊10例,皆为念珠菌血症(白念珠菌4例,近平滑念珠菌3例,光滑念珠菌、热带念珠菌和克柔念珠菌各1例);临床诊断肺IFI 5例(念珠菌3例,曲霉2例);拟诊肺IFI 5例,病原真菌不明。冠状动脉搭桥(CABG)术8例,瓣膜手术8例,胸主动脉瘤手术2例,先天性心脏病(先心病)和马方综合征手术各1例。卡泊芬净的使用时间中位数为18(1～55)d。1例于用药当天死于心脏骤停疗效无法判断,19例可评估患者中,痊愈10例(10/19,52.6%),显效4例(4/19,21.1%),总有效率为73.7%,进步3例,无效2例。死亡6例(6/20,病死率30.0%)。治疗过程中未发现与卡泊芬净有关的不良反应。结论:卡泊芬净是治疗心脏术后并发IFI的有效安全药物,值得进一步临床验证。     

Fatal outcome after heart transplantation caused by Aspergillus lentulus

Opportunistic invasive fungal infections are a major cause of mortality in immunocompromised patients. Early diagnosis of invasive aspergillosis and proper identification of the causative agent is crucial for guidance of therapy. Accurate differentiation of Aspergillus lentulus, a filamentous fungus often misidentified as atypical Aspergillus fumigatus, is of concern as multiple antifungal drugs show a reduced susceptibility. This is the first report, to our knowledge, of a proven pulmonary invasive fungal infection caused by A. lentulus after heart transplantation.     

Colonization With Small Conidia Aspergillus Species Is Associated With Bronchiolitis Obliterans Syndrome: A Two‐Center Validation Study

Aspergillus colonization after lung transplantation may increase the risk for bronchiolitis obliterans syndrome (BOS), a disease of small airways. We hypothesized that colonization with small conidia Aspergillus species would be associated with a greater risk of BOS, based upon an increased likelihood of deposition in small airways. We studied adult primary lung recipients from two large centers; 298 recipients at University of California, Los Angeles and 482 recipients at Duke University Medical Center. We grouped Aspergillus species by conidia diameter ≤3.5 μm. We assessed the relationship of colonization with outcomes in Cox models. Pre‐BOS colonization with small conidia Aspergillus species, but not large, was a risk factor for BOS (p = 0.002, HR 1.44, 95% CI 1.14–1.82), along with acute rejection, single lung and Pseudomonas. Colonization with small conidia species also associated with risk of death (p = 0.03, HR 1.30, 95% CI 1.03–1.64). Although other virulence traits besides conidia size may be important, we have demonstrated in two large independent cohorts that colonization with small conidia Aspergillus species increases the risk of BOS and death. Prospective evaluation of strategies to prevent Aspergillus colonization of small airways is warranted, with the goal of preserving lung allograft function as long as possible.     

霉菌性脊柱炎1例并文献复习

目的探讨霉菌性脊柱炎的临床表现、影像特征和病理特点,提高对霉菌性脊柱炎的认识和鉴别诊断能力。方法回顾性分析1例经手术病理证实的霉菌性脊柱炎病人的影像及病理资料并行文献复习。结果 CT检查显示胸4～胸7椎体广泛骨质硬化伴有周围软组织肿块,病变内部可见散在小片状骨质破坏区,邻近椎间隙无明显变窄;MRI显示胸4～胸8椎体可见斑片状异常信号影,T_1WI上呈低信号,T_2WI上呈稍高信号,抑脂序列呈高信号,邻近椎间盘未见明显异常,增强检查病变椎体、椎旁及硬膜外肿块呈明显强化。术后病理诊断为霉菌感染,血清曲霉菌半乳甘露聚糖检测为阳性。结论霉菌性脊柱炎罕见,其临床和影像表现无特异性,确诊需依赖于病理组织学检查。     

曲霉菌对唑类抗真菌药物的耐药机制研究进展

侵袭性曲霉病是由致病曲霉菌引起的危及生命的真菌感染,主要致病菌为烟曲霉,而唑类抗真菌药物是临床治疗的首选。目前已上市的唑类抗真菌药物包括伊曲康唑,伏立康唑,泊沙康唑和伊沙康唑。然而,流行病学研究发现曲霉菌对唑类抗真菌药物的耐药率呈逐年上升趋势,给临床治疗造成了威胁。其中,Cyp51A蛋白突变、外排系统高表达以及环境耐药机制等多种因素都参与唑类抗真菌药物的耐药。因此,本文综述近年来有关曲霉菌对唑类抗真菌药物的耐药机制,以期为耐药监测、耐药菌控制和新药研发提供理论依据。     

Evaluating the use of PCR for diagnosing invasive aspergillosis

Introduction: Aspergillus species, primarily Aspergillus fumigatus, are still the most emerging fungal pathogens. Within recent years, novel molecular methods have been developed to improve the diagnosis of life-threatening invasive aspergillosis in high risk patients. Especially patients with malignant hematological diseases undergoing intensive chemotherapy are at risk and mortality rates are exceptionally high, in part due to difficulties and delays in establishing a microbiologic diagnosis. Early diagnosis and treatment are crucial for an adequate therapeutical management, but, however, are hardly achieved in the clinical setting because most of the current conventional diagnostic tools either lack specificity or acceptable sensitivity at the critical early phase of the infection.

Areas covered: To review the clinical value, advantages and problems as well as drawbacks of molecular approaches, especially polymerase chain reaction (PCR)-based assays to detect genomic DNA of Aspergillus species in clinical samples of immunocompromised, especially hematological patients at high risk for IA, a comprehensive review of the literature was performed and expert opinion was expressed.

Expert commentary: The results of numerous attempts to diagnose invasive aspergillosis by PCR-based detection of fungal genome in clinical samples highlight the potential of the PCR technique to improve early diagnosis of invasive aspergillosis in patients with hematological malignancies during intensive antineoplastic treatment, combined with imaging surveillance and serologic diagnostic tools. Further comparative validation of reliable assays in prospective multicenter studies is mandatory and urgently needed in order to establish a harmonization and standardization, so that ‘gold standard assays’ may be incorporated into diagnostic and therapeutic algorithms that improve the prognosis of patients with life-threatening infections caused by Aspergillus species.     

Fungal transformation of androsta-1,4-diene-3,17-dione by Aspergillus brasiliensis

Background

The biotransformation of steroids by fungal biocatalysts has been recognized for many years. There are numerous fungi of the genus Aspergillus which have been shown to transform different steroid substances. The possibility of using filamentous fungi Aspergillus brasiliensis cells in the biotransformation of androsta-1,4-diene-3,17-dione, was evaluated.

Methods

The fungal strain was inoculated into the transformation medium which supplemented with androstadienedione as a substrate and fermentation continued for 5 days. The metabolites were extracted and isolated by thin layer chromatography. The structures of these metabolites were elucidated using ¹H-NMR, broadband decoupled ¹³C-NMR, EI Mass and IR spectroscopies.

Results

The fermentation yielded one reduced product: 17β-hydroxyandrost-1,4-dien-3-one and two hydroxylated metabolites: 11α-hydroxyandrost-1,4-diene-3,17-dione and 12β-hydroxyandrost-1,4-diene-3,17-dione.

Conclusions

The results obtained in this study show that A. brasiliendsis could be considered as a biocatalyst for producing important derivatives from androstadienedione.     

一株海兔来源真菌 Aspergillus terreus丁内酯类化合物及其生物活性研究

摘要：目的 在生物活性和化学方法指导下,从1株海兔来源真菌 Aspergillus terreus (RA29-5)中分离鉴定海洋天然产物,并对其进行生物活性评价。方法 运用硅胶柱层析、Sephadex LH-20凝胶柱层析和HPLC等方法分离纯化化合物,利用NMR等现代波谱分析方法,对化合物进行结构鉴定,并对化合物进行抗菌、卤虫致死和斑马鱼胚胎毒性活性评价。结果 鉴定了 9 个丁内酯类化合物 (1～9) 的结构;抗菌活性表明,除化合物 6 和 9 外,所有化合物对四株致病细菌白色葡萄球菌 Staphylococcus epidermidis、金黄色葡萄球菌 Staphylococcus aureus、蜡状芽孢杆菌 Bacillus subtilis 和四联球菌 Tetragenococcus halophilus 都显示一定的抗菌活性;化合物 1～4 和7均对真菌芒果叶枯菌 Pestalotia mangiferae 显示抗菌活性;特别的,化合物 7 对测试的13株致病菌都具有广谱地抗菌活性,其MIC值在1.11~8.88 μmol/L之间;此外,还对化合物的抗菌活性构效关系进行了初步探讨。结论 海兔来源真菌 A. terreus (RA29-5) 可产生结构多样的丁内酯类化合物,该类化合物具有开发成抗菌剂的潜力。