Fungal contamination of bedding

BACKGROUND: It is currently believed that most fungal exposure occurs external to the home. AIMS: To enumerate the fungal flora of used synthetic and feather pillows and the dust vacuumed from them, in the UK. METHODS: 10 pillows aged between 1.5 and >20 years in regular use were collected and quantitatively cultured for fungi. Swatches were taken from nine sections of the pillow and dust was also collected by vacuum from five pillows. Pillow vacuuming was carried out prior to pillow culture. All were cultured at room temperature, 30 and 37 degrees C for 7 days in broth before plating, and a subset were also cultured for 24 h in broth and then plated. Fungi were identified by standard morphological methods. RESULTS: The commonest three species isolated were Aspergillus fumigatus (n = 10), Aureobasidium pullulans (n = 6) and Rhodotorula mucilaginosa (n = 6). Another 47 species were isolated from pillows and vacuum dust. The number of species isolated per pillow varied from 4 to 16, with a higher number from synthetic pillows. Compared with the nonallergenic A. pullulans, more A. fumigatus was found in synthetic than feather pillows. CONCLUSIONS: We have examined pillows for fungal contamination, and show that the typical used pillow contains a substantial load of many species of fungi, particularly A. fumigatus. Given the time spent sleeping, and the proximity of the pillow to the airway, synthetic and feather pillows could be the primary source of fungi and fungal products. This has important implications for patients with respiratory disease, and especially asthma and sinusitis.     

肉桂醛和柠檬醛对黄曲霉及烟曲霉细胞DNA与RNA的影响

目的研究肉桂醛、柠檬醛对黄曲霉和烟曲霉细胞DNA、RNA水平的影响,以期探明其抗真菌的作用机制。方法黄曲霉、烟曲霉接种在含有不同浓度药物的蔡氏固体培养基中,同时设不加药物为空白对照,置26.5℃恒温培养3～6d,将对照组和用药组真菌细胞进行激光扫描共聚焦显微镜观察并作细胞扫描图像分析,以对DNA、RNA进行定量和定位观察。结果用药组DNA、RNA水平发生不同变化,出现多核分生孢子。结论肉桂醛、柠檬醛直接或间接影响了真菌细胞遗传物质的正常合成,以至不能完成正常细胞周期,影响分生孢子梗的正常分化,从而抑制真菌生长、繁殖。     

Effects of Cymbopogon citratus L. essential oil on the growth, morphogenesis and aflatoxin production of Aspergillus flavus ML2-strain

The mycelial growth of Aspergillus flavus Link was completely inhibited using 1.5 (microl/ml or 2.0 (microl/ml of Cymbopogon citratus essential oil applied by fumigation or contact method in Czapek's liquid medium, respectively. This oil was found also to be fungicidal at the same concentrations. The sublethal doses 1.0 and 1.5 (microl/ml inhibited about 65% of fungal growth after five days of incubation and delayed conidiation as compared with the control. Microscopic observations using Light Microscope (LM), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) were carried out to determine the ultra structural modifications of A. flavus hyphae after treatment with C. citratus essential oil. The hyphal diameter decreased and hyphal wall appeared as precipitates and disappeared in some regions. This oil also caused plasma membrane disruption and mitochondrial structure disorganization. Moreover, Ca(+2), K(+) and Mg(+2) leakages increased from the fumigated mycelium and its total lipid content decreased, while the saturated and unsaturated fatty acids increased. One of the most important results obtained during this study was the ability of C. citratus essential oil at its sublethal dose to completely inhibit aflatoxin B(1) production from A. flavus. These findings increase the possibility of exploiting C. citratus essential oil as an effective inhibitor of biodegradation and storage contaminating fungi and also in fruit juice preservation.     

肉桂醛和柠檬醛对黄曲霉及烟曲霉细胞DNA与RNA的影响

目的研究肉桂醛、柠檬醛对黄曲霉和烟曲霉细胞DNA、RNA水平的影响,以期探明其抗真菌的作用机制。方法黄曲霉、烟曲霉接种在含有不同浓度药物的蔡氏固体培养基中,同时设不加药物为空白对照,置26.5℃恒温培养3～6d,将对照组和用药组真菌细胞进行激光扫描共聚焦显微镜观察并作细胞扫描图像分析,以对DNA、RNA进行定量和定位观察。结果用药组DNA、RNA水平发生不同变化,出现多核分生孢子。结论肉桂醛、柠檬醛直接或间接影响了真菌细胞遗传物质的正常合成,以至不能完成正常细胞周期,影响分生孢子梗的正常分化,从而抑制真菌生长、繁殖。     

Biological Control of Aflatoxin Contamination of Crops

Aflatoxin contamination of crops compromises the safety of food and feed supplies and causes significant economic losses each year. Of the many research approaches being studied to reduce and, ultimately, eliminate aflatoxin contamination, biological control is one of the more promising, particularly for the near‐term. Numerous organisms have been tested for biological control of aflatoxin contamination including bacteria, yeasts, and nontoxigenic strains of the causal organisms, Aspergillus flavus and A. parasiticus. Most of the field successes to date have been achieved by applying certain nontoxigenic strains of A. flavus and A. parasiticus to soil of susceptible crops, such as peanuts, cotton, and corn. The applied strains occupy the same niche as the naturally occurring toxigenic strains and competitively exclude them when crops are susceptible to infection. Various formulations have been used to apply the nontoxigenic strains to soil, but the most effective methods have been to combine the desired strain with a carrier/substrate, such as a small grain. This was done either by minimally growing the desired strain on sterilized grain or by coating the surface of the grain with conidia of the strain. After application to the field and uptake of moisture, the fungus completely colonizes the grain, and abundant sporulation provides inoculum levels sufficient to achieve a competitive advantage for the nontoxigenic strain. In several years of field studies, particularly with peanuts and cotton, significant reductions in aflatoxin contamination in the range of 70–90% have been achieved consistently. Two separate products have recently received EPA registration as biopesticides to control aflatoxin contamination in cotton (AF36) and peanuts (afla‐guard®).     

Cutaneous manifestations and dermoscopic findings are important clues to the diagnosis of Talaromyces marneffei in HIV patients with immune reconstitution inflammatory syndrome: A case report and literature review

Talaromyces (formerly Penicillium) marneffei is a dimorphic fungus that causes talaromycosis (formerly penicilliosis). The condition is predominantly found in patients with HIV. Important diagnostic clues are a history of living or travelling in endemic areas, and central umbilicated skin lesions. Dermoscopy is particularly useful for providing rapid bedside information, with a round, whitish, amorphous structure being the most common finding. Immune reconstitution inflammatory syndrome (IRIS) may occur. Driven by the initiation of antiretroviral therapy, IRIS is an exaggerated response of T cells to pathogens. Although mycobacterial and cryptococcal opportunistic infections are common with IRIS, a linkage between T. marneffei and IRIS has rarely been reported. Here, we report on a literature review of patients with HIV who developed IRIS associated with talaromycosis. Dermatologists should be aware of the cutaneous and dermoscopic findings of talaromycosis as they provide important clues that enable its early diagnosis and treatment.     

Successful treatment of hepatic and mesh Aspergillosis in a neonate with giant omphalocele

Aspergillosis is a rare and life-threatening fungal infection in immunocompetent children, particularly in infants. We present a case of invasive Aspergillosis (IA) that developed hepatic and mesh infection due to Aspergillus flavus following the rupture of a giant omphalocele. A male baby was born at 37 weeks of gestation with a giant omphalocele. No other congenital abnormalities were found. In the pediatric surgery operation room, the amniotic membrane seemed to be ruptured in some parts, which had been repaired within a few hours of birth. No further intervention to reduce the volume of visceral organs could be performed due to the tiny abdominal cavity. Postoperatively piperacillin-tazobactam and fluconazole were empirically initiated. Abdominal defects had been covered with polypropylene polylactic acid synthetic Mesh on postnatal day 11 to protect the organs and prevent abdominal infections. Fungal hepatic lesions were observed during surgery, and black necrotic lesions were also observed on the mesh on day 12. On the 16th postnatal day, Aspergillus flavus grew in the wound, graft, hepatic biopsy cultures. Serum galactomannan (GM) assay test was positive (GM:2.9), and voriconazole was initiated. All necrotic lesions resolved with liposomal amphotericin B (L-AmB) and voriconazole treatment, and antifungal therapy was discontinued after 134 days. Eye examination for the retinopathy didn't show any abnormalities. The patient was discharged with full recovery on day 155.In conclusion, IA is a rare and life-threatening infection in the neonatal period. To the best of our knowledge, this is the first case of hepatic and mesh infection caused by Aspergillus flavus that was successfully treated with voriconazole and l-AmB.     

Clinical,genetic and immunological characteristics of 40 Chinese patients with CD40 ligand deficiency

CD40 ligand (CD40L) deficiency is a rare but life‐threatening primary immunodeficiency caused by mutations in the CD40L gene. Here, we investigated a cohort of 40 genetically diagnosed CD40L‐deficient patients from the Chinese mainland, analysed their clinical and genetic data, and examined CD40L expression, the proportion of T cell subsets, B cell subsets and T follicular helper (Tfh) cells. The aim was to provide a complete picture of CD40L deficiency. Initial presentations of the patient cohort mainly involved recurrent fever (47.5%) and sinopulmonary infection (42.5%). Life‐threatening infections (42.5%), caused by various pathogens, were the most serious threats faced by CD40L‐deficient patients, while neutropenia (57.5%) remained the most common complication. Opportunistic infections, including Pneumocystis carinii pneumonia and invasive fungal disease associated with Talaromyces marneffei, were also common in the cohort. In addition, seven patients (17.5%) suffered BCGitis/BCGosis, which is a major problem facing a planned immunization programme in China. It was intriguing that reduced IgM levels were observed in 12.5% of patients, while normal or elevated IgA levels were shown in 47.5% of patients. Thirty‐seven unique mutations were identified in 40 patients; of these, 10 were novel. Furthermore, we observed a lower percentage of NK cells, Tfh cells, and central memory CD4⁺ T cells, and an extremely small class‐switched memory B cell population, in CD40L‐deficient patients. Patients who underwent hematopoietic stem cell transplantation experienced better disease remission. Taken together, our data establish the largest database about CD40L deficiency in China and provide genetic, immunologic and clinical information about Chinese CD40L‐deficient patients.     

MALDI-TOF MS鉴定马尔尼菲篮状菌的实验条件优化

目的构建用于基质辅助激光解吸电离飞行时间质谱技术(MALDI-TOF MS)鉴定马尔尼菲篮状菌的数据库,并探索用于MALDI-TOF MS鉴定马尔尼菲篮状菌的最佳培养条件和前处理方法。方法利用8株马尔尼菲篮状菌构建自建数据库,比较不同培养基[沙保弱葡萄糖琼脂培养基(SDA)、沙氏葡萄糖肉汤培养基(SDB)]、培养温度(28、35℃)、培养天数、前处理方法(甲酸乙腈法、直涂法)对质谱谱图质量及鉴定正确率的影响。结果在VITEK MS科研模式(RUO模式)中成功构建马尔尼菲篮状菌质谱自建数据库。SDA较SDB更适合MALDI-TOF MS鉴定马尔尼菲篮状菌,后者采集的质谱谱图中干扰峰较多。两种温度培养采集的质谱谱图的特征峰相似,但35℃菌落的鉴定正确率略高。培养3~5 d时的菌落鉴定正确率均高于71.4%,其中培养5 d时鉴定正确率最高,可达100.0%。甲酸乙腈法的提取效果优于直涂法。结论马尔尼菲篮状菌在SDA上35℃培养3~5 d,并使用甲酸乙腈法进行前处理可得到最佳的鉴定正确率。这对于形态不典型的马尔尼菲篮状菌同样适用。     

多枝柽柳内生真菌Talaromyces stollii的次级代谢产物研究

摘要：通过硅胶柱色谱、Sephadex LH-20 凝胶柱色谱和反相高效液相色谱等多种分离和纯化方法,从多枝柽柳内生真菌 Talaromyces stollii的大米发酵培养物中分离得到了7个次级代谢产物,经ESI-MS、1H NMR、13C NMR和旋光比较等多种波谱 技术,分别鉴定为penipyridone D(1), penipyridone E(2), penipyridone F(3), berkeleyamide C(4), chrodrimanin A(5),(S)-pestalasin A(6),peniazaphilin B(7),化合物1~4为少有的苄基吡啶酮类生物碱,首次从蓝状菌属真菌中分离得到。化合物5和6对KLF2具有 一定的上调活性。