Effect of different sample volumes on the DNA extraction of Aspergillus fumigatus from whole blood

Five methods were compared, using conventional PCR, for the isolation of DNA from Aspergillus fumigatus conidia from 1–3-mL samples of whole blood. A lower detection threshold of Aspergillus conidia was achieved using 3-mL rather than 1-mL samples with three of five methods tested.     

霉菌酸性蛋白酶高产突变菌株9169的选育

对一株宇佐美曲霉进行紫外光、微波和60Co的逐级诱变育种,使酸性蛋白酶产量从2800U/mL提高到7200U/mL.突变株传代多次,产酶性能保持稳定;对突变株与出发株的发酵过程进行了比较研究,发现突变株最大产酶时间提前10h以上,而培养基pH值对产酶有一定影响.     

Pulmonary hydatid disease with coexistent aspergillosis: An incidental finding

There are only a few case reports in the literature on the coexistence of aspergillosis and echinococcosis. We report a case of a 45-year-old immunocompetent patient who presented with a history of intermittent fever and cough with haemoptysis. Chest x-ray and CECT showed a large cystic lesion in right lower lobe with multiple floating membranes. Histopathological examination of cyst wall revealed the laminated membrane of hydatid cyst along with infiltration of its wall with septate fungal hyphae with acute angle branching suggestive of aspergillosis.     

血清曲霉菌游离DNA定量PCR检测方法的建立及应用初探

目的 建立并评价从血清中检测曲霉游离DNA的定量PCR方法.方法 合成曲霉28s rDNA基因特异广谱引物和Taqman探针,建立定量PCR检测方法,并进行方法学评价.用建立的方法检测33例患者的GM阳性血清标本.结果 定量PCR方法灵敏度为2拷贝/反应,标准曲线Y=-3.629X+40.187,相关系数R2为0.997 6.定量PCR方法检测33例患者的首次GM阳性血清标本,对诊断侵袭性曲霉感染的敏感性84％(21/25)、特异性87.5％(7/8)、阳性预测值95.5％(21/22)、阴性预测值63.6％(7/11).PCR阳性与PCR阴性病例组间侵袭性曲霉感染诊断率有统计学差异(95.5％ vs 36.4％),PCR阳性与侵袭性曲霉感染诊断有相关性(RR=2.625).结论 血清曲霉游离DNA定量PCR检测有助于侵袭性曲霉感染的早期诊断.     

Absorption and Excretion of Parathion by Spraymen

Significant amounts of the urinary metabolite p-nitrophenol were detected in the urine of spraymen as long as ten days after last exposure to the organophosphorus insecticide, parathlon. Approximately two days after exposure, excretion was insignificant during late night and early morning hours, but reached higher levels during midday. The height of Immediate postexposure excretory peaks and the delayed midday rises in excretion seemed to vary directly with the temperature. Bathing after exposure was associated with a rapid decrease in p-nitrophenol excretion, Tests considering only one route of exposure at a time Indicated that the dermal route represents a potentially greater source of absorption than the respiratory route for orchard spraymen using liquid parathion formulations under the conditions of this study. However, with equivalent absorbed dosages the respiratory route is the more hazardous.     

Biochemical and cellular activity of chemically synthesized elastase inhibitor (S-AFUEI) from Aspergillus fumigatus

PurposeElastase, produced by Aspergillus fumigatus and A. flavus, is an important pathogenic factor in pulmonary aspergillosis. We investigated the possibility of using A. fumigatus-derived A. fumigatus elastase inhibitor (AFUEI) as a therapeutic agent. As native-AFUEI (N-AFUEI) has an extremely low yield, we generated a synthetic-AFUEI (S-AFUEI) and investigated whether S-AFUEI has a biological activity against A. fumigatus elastase (AFUE) and inhibits cytotoxicity.MethodologyA. fumigatus was cultured in Yeast Carbon Base (YCB) -elastin culture medium for 3–7 days, and AFUE was purified by chromatography using DE52 cellulose and Sephadex G-75 column. Elastolytic activity was examined using Glt-Ala-Ala-Pro-Leu-pNA (GAAPLNA) as the substrate. The hydrolytic activity of AFUE was determined using the characteristic substrates, fibrinogen and collagen (Type IV), and human cell cytotoxicity was measured colorimetrically. Furthermore, the inhibitory effect of S-AFUEI on these activities was examined.ResultsWe confirmed that S-AFUEI demonstrated elastase inhibitory activity and heat stability equivalent to that demonstrated by N-AFUEI, and inhibited human collagen hydrolytic activity and human fibrinogen hydrolytic activity. Further, S-AFUEI inhibited cytotoxicity in AFUE human pulmonary artery endothelial cells (HPAEC), human small airway epithelial cells (HSAEC), and human pulmonary alveolar epithelial cells (HPAEpiC).ConclusionAs S-AFUEI strongly inhibited cytotoxicity induced by elastase in human-derived cells, it could prove beneficial for the treatment of pulmonary aspergillosis.     

Bromodomain inhibitor I‐BET151 suppresses immune responses during fungal–immune interaction

Changes in the epigenetic landscape of immune cells are a crucial component of gene activation during the induction of inflammatory responses, therefore it has been hypothesized that epigenetic modulation could be employed to restore homeostasis in inflammatory scenarios. Fungal pathogens cause a large burden of morbidity and even mortality due to the hyperinflammatory processes that induce mucosal, allergic or systemic infections. Bromodomain and extraterminal domain (BET) proteins are considered as one as the most tantalizing pharmacological targets for the modulation of inflammatory responses at the epigenetic level. Nothing is known of the role of BET inhibitors on the inflammation induced by fungal pathogens. In the present study, we assessed the in vitro efficacy of the small molecular histone mimic BET inhibitor I‐BET151 to modulate innate immune responses during fungal–immune interaction with the clinically relevant fungal pathogens Candida albicans and Aspergillus fumigatus. Our results prove that BET inhibitors (I‐BETs) represent an important modulator of inflammation induced by fungal pathogens: both direct production of proinflammatory cytokines and the induction of trained immunity were inhibited by I‐BET151. These modulatory effects are likely to have important potential implications in clinically relevant situations.     

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.