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This case study with chart review describes the aerobic and anaerobic microbiology of specimens obtained from 47 patients with Aspergillus spp fungus ball. Bacteria were recovered from 32 of the 47 (68%) patients. Eighty-six isolates, 29 aerobic and facultatives and 57 anaerobic, were recovered. Aerobic and facultatives only were recovered in 6 instances (19% of culture-positive specimens), anaerobes only in 11 (34%), and mixed aerobes and anaerobes in 15 (47%). The predominant aerobes were Staphylococcus aureus (6 isolates), α-hemolytic streptococci (5 isolates), Enterobacteriacae (4 isolates), and microaerophilic streptococci (4 isolates). The predominant anaerobes were Gram-negative bacilli (26), Peptostreptococcus spp (14), and Fusobacterium spp. (10). Twenty-two β-lactamase-producing bacteria were recovered from 15 patients. These included all 6 S aureus and 2 Bacteroides fragilis group isolates, 4 of 10 of Fusobacteria, and 7 of 19 Prevotella and Porphyromonas. This study demonstrates the recovery of polymicrobial aerobic-anaerobic flora in the sinuses of patients with fungus ball.

Marine microorganisms have proved to be an important source of pharmacologically active metabolites, and a growing number of marine-derived fungi have been reported to produce metabolites with unique structures and interesting biological activities.1, 2 The genus Aspergillus (Moniliaceae), with over 180 species, has attracted considerable attention as a rich source of alkaloids, terpenoids, xanthones, polyketides and etc, some of which showed antifungal, antibacterial, anti-HIV and cytotoxic activities.3, 4, 5 In order to obtain new bioactive metabolites from marine fungi, we investigated on the marine fungal strain Aspergillus sydowii SCSIO 00305 isolated from a healthy tissue of Verrucella umbraculum. Bioassay-guided fractionation led to the isolation of a new indole diketopiperazine alkaloid, cyclotryprostatin E (1), together with nine known ones, [4-(2-methoxyphenyl)-1-piperazinyl][(1-methyl-1H-indol-3-yl)]-methanone (2), cyclotryprostatin B (3),6 fumiquinazoline D (4),7 fumitremorgin B (5),8 fumiquinazoline C (6),7 fumiquinazoline B (7),7 fumiquinazoline A (8),7 fumiquinazoline F (9),7 fumiquinazoline G (10)7 from a culture broth of the strain. The structures of compounds (1) and (2) were characterized by spectroscopic data interpretation. Compound (2) was a synthetical compound, however, no reference for it. The NMR data and biology source of (2) were reported for the first time. We present herein the fermentation, isolation, structure elucidation and cytotoxicity of compounds (1) and (2).

Response to http://onlinelibrary.wiley.com/doi/10.1111/j.1399-3062.2011.00663.x/pdf

Intracranial fungal granulomas are rare and of the histologically verified granulomas, Aspergillus spp. is the commonest causative fungal pathogen. Most of the reported large series of aspergillus granulomas are from countries with temperate climate like India, Pakistan, Sudan, and Saudi Arabia. In contrast to disseminated aspergillosis that occurs in immunosuppressed individuals, most of the intracranial aspergillus granulomas are reported in immunocompetent individuals. The temperature, humidity, high spore content in the atmosphere during ploughing, and occupation as agricultural worker are implicated in the pathogenesis. The sinocranial spread is the most common route of intracranial extension. Extracerebral firm fibrotic lesions and skull base lesions are common. Extensive fibrosis and large number of multinucleated giant cells are the characteristic histological features and these pathological features have therapeutic relevance.

Patients with chronic granulomatous disease (CGD) cannot produce reactive oxygen species (ROS) due to a genetic defect in the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system. Dysregulation of the l-tryptophan metabolism in mice with defects in NADPH oxidase, resulting in overproduction of interleukin (IL)-17, has been proposed to link ROS defects with hyperinflammation and susceptibility to pulmonary aspergillosis. In this study, we assessed the l-tryptophan metabolism and cytokine profiles in response to fungal pathogens in CGD patients. Peripheral blood mononuclear cells (PBMCs) from CGD patients showed increased production of IL-6, tumor necrosis factor-α, and interferon-γ upon stimulation with Aspergillus or Candida species, while IL-17A production was strikingly low compared with healthy controls. Indoleamine 2,3-dioxygenase expression was similar in PBMCs and neutrophils from CGD patients compared with healthy controls. Conversion of l-tryptophan to l-kynurenine, as measured by high-performance liquid chromatography, did not differ between CGD patients and healthy controls. Moreover, adding l-kynurenine to the cell cultures did not suppress fungal-induced IL-17A production. Although PBMCs of CGD patients produced more proinflammatory cytokines after stimulation, IL-17A production was strikingly low in response to fungal pathogens when compared with healthy controls. In addition, cells from CGD patients did not display a defective l-tryptophan metabolism.

In the filamentous fungus Aspergillus nidulans, both microtubules and actin filaments are important for polarized growth at the hyphal tip. Less clear is how different microtubule-based and actin-based motors work together to support this growth. Here we examined the role of myosin-V (MYOV) in hyphal growth. MYOV-depleted cells form elongated hyphae, but the rate of hyphal elongation is significantly reduced. In addition, although wild type cells without microtubules still undergo polarized growth, microtubule disassembly abolishes polarized growth in MYOV-depleted cells. Thus, MYOV is essential for polarized growth in the absence of microtubules. Moreover, while a triple kinesin null mutant lacking kinesin-1 (KINA) and two kinesin-3s (UNCA and UNCB) undergoes hyphal elongation and forms a colony, depleting MYOV in this triple mutant results in lethality due to a severe defect in polarized growth. These results argue that MYOV, through its ability to transport secretory cargo, can support a significant amount of polarized hyphal tip growth in the absence of any microtubule-based transport. Finally, our genetic analyses also indicate that KINA (kinesin-1) rather than UNCA (kinesin-3) is the major kinesin motor that supports polarized growth in the absence of MYOV.

PURPOSE: Invasive fungal infections (IFI) are a major cause of infection-related mortality during induction chemotherapy of acute leukemia (AL) patients. Data on antifungal prophylaxis (AFP) in children are limited by retrospective design, small sample size, and variability of chemotherapy phases having different risk of IFI. There are no data comparing voriconazole versus amphotericin B (AmB) as AFP in either adult/pediatric AL. The objectives of this study were to compare efficacy and toxicity of AmB and voriconazole as AFP in pediatric AL patients.

PATIENTS AND METHODS: As a pilot study, total 100 children (≤15 y) with denovo acute myeloid leukemia and acute lymphoblastic leukemia were randomized to either oral voriconazole or low dose intravenous AmB as AFP during induction chemotherapy.

RESULTS: Failure of prophylaxis occurred in 14/50 patients in voriconazole arm (1 proven mucormycosis, 1 possible IFI, 11 empirical antifungal therapy, and 1 withdrawal owing to hepatotoxicity) and 17/50 patients in AmB arm (3 possible IFI, 13 empirical antifungal therapy, and 1 withdrawal owing to difficult venous access) (P=0.66). Of the 29 patients who had failure of prophylaxis unrelated to drug toxicity, computed tomography of the chest showed infiltrates in 10 patients with 3/12 in voriconazole arm and 7/16 in AmB arm (P=0.43). Drug-related serious adverse events were 6% versus 30% in voriconazole and AmB arms, respectively (P<0.01). Further, total number of toxicities per patient in AmB arm were significantly higher as compared with voriconazole arm (P<0.0001).

CONCLUSION: This is the first randomized study comparing voriconazole with AmB in pediatric AL patients as AFP during induction chemotherapy; our results showed that oral voriconazole seems to be comparable with AmB with less toxicity and more convenience. (ClinicalTrials.gov identifier: NCT00624143).

The detection of 1,3-β-d-glucan (BDG), a cell wall component of several medically important fungi, is a promising tool for the diagnosis of invasive pulmonary aspergillosis. The aim of this study was to evaluate the diagnostic accuracy of the BDG test in invasive pulmonary aspergillosis (IPA) by focusing on the optimal cut-off value. Methods: The records of the Infection Control Committee were reviewed to identify patients with haematological malignancies and stem cell transplantation who had at least 1 BDG (Fungitell kit) measurement during the period January 2008 through April 2011. The European Organization for Research and Treatment of Cancer and the Mycoses Study Group (EORTC/MSG) criteria (independent of BDG results) were used to categorize the patients with IPA. Patients with possible IPA were not included in the study. Results: A total of 128 patients (50 with proven or probable IPA) were included in the study. At the manufacturer's recommended cut-off value of 80 pg/ml, the sensitivity of BDG was 66% (95% CI 51.2-78.7), specificity 75.6% (95% CI 64.6-84.5), positive predictive value (PPV) 63.4%, and negative predictive value (NPV) 77.6%. A receiver operating characteristic (ROC) curve was constructed to define the optimum serum BDG cut-off for the diagnosis of IPA. At a cut-off value of 181 pg/ml, the sensitivity was 52% (95% CI 37.4-66.3), specificity 94.8% (95% CI 87.4-98.6), PPV 86.7%, and NPV 75.5%. Conclusions: Although higher cut-off levels increased the specificity of the BDG test, sensitivity decreased to an unacceptable level; the commercially recommended cut-off value appears to be appropriate for screening purposes.

Mycotic keratitis is an important cause of corneal blindness world over including India. Geographical location and climate are known to influence the profile of fungal diseases. While there are several reports on mycotic keratitis from southern India, comprehensive clinico-microbiological reports from eastern India are few. The reported prevalence of mycotic keratitis are 36.7%,36.3%,25.6%,7.3% in southern, western , north- eastern and northern India respectively. This study reports the epidemiological characteristics, microbiological diagnosis and treatment outcome of mycotic keratitis at a tertiary eye care center in eastern India.

METHODS: A retrospective review of medical and microbiology records was done for all patients with laboratory proven fungal keratitis.

RESULTS: Between July 2006 and December 2009, 997 patients were clinically diagnosed as microbial keratitis. While no organisms were found in 25.4% (253/997) corneal samples, 23.4% (233/997) were bacterial, 26.4% (264/997) were fungal (45 cases mixed with bacteria), 1.4% (14/997) were Acanthamoeba with or without bacteria, 23.4% (233/997) were microsporidial with or without bacteria. Two hundred fifteen of 264 (81.4%, 215/264) samples grew fungus in culture while 49 corneal scrapings were positive for fungal elements only in direct microscopy. Clinical diagnosis of fungal keratitis was made in 186 of 264 (70.5%) cases. The microscopic detection of fungal elements was achieved by 10% potassium hydroxide with 0.1% calcoflour white stain in 94.8%(238/251) cases. Aspergillus species (27.9 %, 60/215) and Fusarium species (23.2%, 50/215) were the major fungal isolates. Concomitant bacterial infection was seen in 45 (17.1%, 45/264) cases of mycotic keratitis. Clinical outcome of healed scar was achieved in 94 (35.6%, 94/264) cases. Fifty two patients (19.7%, 52/264) required therapeutic PK, 9 (3.4%, 9/264) went for evisceration, 18.9% (50/264) received glue application with bandage contact lens (BCL) for impending perforation, 6.1% (16/264) were unchanged and 16.3% (43/264) were lost to follow up. Poor prognosis like PK (40/52, 75.9%, p<0.001) and BCL (30/50, 60%, p<0.001) was seen in significantly larger number of patients with late presentation (>10 days).

CONCLUSION: The relative prevalence of mycotic keratitis in eastern India is lower than southern, western and northeastern India but higher than northern India, however, Aspergillus and Fusarium are the predominant genera associated with fungal keratitis across India. The response to medical treatment is poor in patients with late presentation.

We developed and assessed the diagnostic value of a novel quantitative nested real-time PCR (QNRT) assay targeting the internal-transcribed (ITS) region of ribosomal DNA (rDNA) in a guinea pig model of invasive pulmonary aspergillosis. Groups of 5 immunosuppressed animals that were infected using an aerosol chamber with A. fumigatus conidia were humanely terminated 1 hour post-inoculation and at days 3, 5, 7 and 11 post challenge, and lung tissue, bronchoalveolar lavage fluid (BAL), whole blood and serum samples were collected. The QNRT-PCR results in the serum and BAL were compared to those achieved with galactomannan and (1→3)-β-D-glucan assays. High levels of fungal burden were detected by QNRT-PCR in both lung tissue and BAL in all infected animals at each time point, and the sensitivity of each assay in BAL was 100% by day 3 and remained so through the remainder of the study. The sensitivity of detection of fungi in whole blood and serum samples was significantly lower and some samples remained negative by all three assays despite the advanced stage of the infection. From these data we can conclude that this novel QNRT-PCR method was highly sensitive for the detection of A. fumigatus from different types of samples in this model. In addition, BAL samples appeared to be the most suitable for the early diagnosis of invasive pulmonary aspergillosis. When testing serum, the use of a combination of available assays may increase the possibility of early detection of this opportunistic mycosis.

Earlier articles

Aspergillus species are increasingly important human pathogens. It is not known whether toxic metabolites of many of these pathogenic species can act as virulence factors in aspergillosis. We examined isolates of aflatoxin and ochratoxin-producing species for toxin production in ex vivo conditions. Seven of the 21 aflatoxin-producing isolates screened produced aflatoxin at 35 and 37 degrees C on the general medium yeast extract sucrose agar (YES). However, none of them produced toxin at these temperatures on brain heart infusion agar (BHA), a medium that mimics human tissue, or on BHA with modified pH or sugar levels. Six of the 12 ochratoxin-producing isolates examined produced toxin at 35 degrees C on YES. All three isolates of A. alliaceus produced ochratoxin on BHA or modified BHA at 37 degrees C. One strain of A. pseudoelegans produced a minute amount of ochratoxin on modified BHA at 37 degrees C. These data indicate that aflatoxin is an unlikely virulence, factor but that ochratoxin may be a potential virulence factor in aspergillosis.

The mycotoxin ochratoxin A (OTA) is a rodent carcinogen produced by species of the ubiquitous fungal genera Aspergillus and Penicillium. OTA is found in a variety of food items and as a consequence is also found in human plasma (average concentrations found in this study: 0.1-1 ng OTA/ml plasma). To improve the scientific basis for cancer risk assessment the toxicokinetic profile of OTA was studied in one human volunteer following ingestion of 395 ng 3H-labeled OTA (3.8 microCi). A two-compartment open model consisting of a central compartment was found to best describe the in vivo data. This two-compartment model consisted of a fast elimination and distribution phase (T1/2 about 20 h) followed by a slow elimination phase (renal clearance about 0.11 ml/min.) and a calculated plasma half-life of 35.55 days. This half-life was approximately eight times longer than that determined previously in rats. In addition, the intraindividual fluctuation of OTA plasma levels was investigated in eight individuals over a period of 2 months. The concentrations determined ranged between 0.2 and 0.9 ng OTA/ml plasma. The plasma levels in some individuals remained nearly constant over time, while others varied considerably (e.g. increase of 0.4 ng/ml within 3 days, decrease of 0.3 ng/ml within 5 days) during the observation period. This intraindividual fluctuation in OTA plasma levels, which may represent differences in OTA exposure and/or metabolism, as well as the large difference in plasma half-life in humans compared to rats must be taken into consideration when the results of rat cancer study data are extrapolated to humans for risk assessment purposes.

Ochratoxin A (OTA) is an immunosuppressant fungal compound, produced by toxigenic species of Aspergillus and Penicillium fungi in a wide variety of climates and geographical regions. The contamination of food by this mycotoxin takes place primarily during preharvest periods. Almost all types of food can be contaminated. In addition, its chemical stability against heat and during industrial food processing makes OTA one of the most abundant food contaminating mycotoxins. Due in part to its long serum half-life in man, almost 100% of all human blood samples from some geographic regions may be positive for OTA. The immunosuppressant activity of OTA is characterized by size reduction of vital immune organs, such as thymus, spleen, and lymph nodes, depression of antibody responses, alterations in the number and functions of immune cells, and modulation of cytokine production. The immunotoxic activity of OTA probably results from degenerative changes and cell death following necrosis and apoptosis, in combination with slow replacement of affected immune cells, due to inhibition of protein synthesis.

Most previous studies on the association between moisture damage and asthma have been cross-sectional and relied on self-reported exposure and health. The present authors studied the association by carrying out careful home inspections among new, clinically determined cases of asthma and controls. New cases of asthma aged 12-84 months (n = 121) were recruited prospectively and matched for year of birth, sex and living area with two randomly selected population controls (n = 241). Trained engineers visited all homes. Both cases and controls had lived >or=75% of their lifetime or the past 2 yrs in their current home. Risk of asthma increased with severity of moisture damage and presence of visible mould in the main living quarters but not in other areas of the house. Cases more often had damage in their bedroom. Associations were comparable for atopic and nonatopic asthma and for children aged >30 months or <or=30 months. The present results, using standardised assessment of exposure and asthma, suggest that moisture damage and mould growth in the main living quarters are associated with the development of asthma in early childhood.

OBJECTIVES: Most previous studies on the association between moisture or mold problems in the home and respiratory symptoms in children were cross-sectional and based on self-reported exposure. The aim of this study was to evaluate the impact of objectively observed moisture damage and visible mold in the homes on early-life respiratory morbidity and atopic sensitization in a birth cohort.

METHODS: Building inspection was performed by building engineers in the homes of 396 children, and the children were followed up with questionnaires from birth to the age of 18 months. Specific immunoglobulin E levels were measured at the age of 1 year.

RESULTS: Doctor-diagnosed wheezing was associated with the severity of moisture damage in the kitchen and with visible mold in the main living area and especially in the bedroom of the child. The risk for parent-reported wheezing apart from cold increased with the severity of moisture damage in the kitchen. Moisture damage in the bathrooms or other interior spaces had no significant association with wheezing. No significant associations were observed for other end points, such as cough, or respiratory infections. There was a suggestion for an increased risk for sensitization to cat dander linked with moisture and mold exposure.

CONCLUSIONS: This birth-cohort study supports previous observations that moisture mold problems in the kitchen and in the main living area increase the risk for wheezing in early childhood. The results underline the importance of assessing separately the health effects of moisture and mold problems in different areas of the home.

BACKGROUND: It is not clear whether associations between respiratory symptoms and indoor mould are causal. A randomised controlled trial was conducted to see whether asthma improves when indoor mould is removed.

METHODS: Houses of patients with asthma were randomly allocated into two groups. In one group, indoor mould was removed, fungicide was applied and a fan was installed in the loft. In the control group, intervention was delayed for 12 months. Questionnaires were administered and peak expiratory flow rate was measured at baseline, 6 months and 12 months.

RESULTS: Eighty-one houses were allocated to the intervention group and 83 to the control group; 95 participants in 68 intervention houses and 87 in 63 control houses supplied follow-up information. Peak expiratory flow rate variability declined in both groups, with no significant differences between them. At 6 months, significantly more of the intervention group showed a net improvement in wheeze affecting activities (difference between groups 25%, 95% CI 3% to 47%; p = 0.028), perceived improvement of breathing (52%, 95% CI 30% to 74%; p<0.0001) and perceived reduction in medication (59%, 95% CI 35% to 81%; p<0.0001). By 12 months the intervention group showed significantly greater reductions than the controls in preventer and reliever use, and more improvement in rhinitis (24%, 95% CI 9% to 39%; p = 0.001) and rhinoconjunctivitis (20%, 95% CI 5% to 36%; p = 0.009).

CONCLUSIONS: Although there was no objective evidence of benefit, symptoms of asthma and rhinitis improved and medication use declined following removal of indoor mould. It is unlikely that this was entirely a placebo effect.

Several illnesses expressed somatically that do not have clearly demonstrated pathophysiological origin and that are associated with neuropsychological complaints are reviewed. Among them are nonepileptic seizures, fibromyalgia, chronic fatigue syndrome, Persian Gulf War unexplained illnesses, toxic mold and sick building syndrome, and silicone breast implant disease. Some of these illnesses may be associated with objective cognitive abnormalities, but it is not likely that these abnormalities are caused by traditionally defined neurological disease. Instead, the cognitive abnormalities may be caused by a complex interaction between biological and psychological factors. Nonepileptic seizures serve as an excellent model of medically unexplained symptoms. Although nonepileptic seizures clearly are associated with objective cognitive abnormalities, they are not of neurological origin. There is evidence that severe stressors and PTSD are associated with immune system problems, neurochemical changes, and various diseases; these data blur the distinctions between psychological and organic etiologies. Diagnostic problems are intensified by the fact that many patients are poor historians. Patients are prone to omit history of severe stressors and psychiatric problems, and the inability to talk about stressors increases the likelihood of suffering from physiological forms of stress.

Although computed tomography (CT) of the thorax has been compared to plain chest radiography and bronchography for demonstration of central bronchiectasis (CB) in allergic bronchopulmonary aspergillosis (ABPA), the CT presentation of the disease is yet to be highlighted. With this in view, the CT appearances in 23 patients with ABPA were evaluated. The scans were assessed for bronchial, parenchymal and pleural abnormalities. Central bronchiectasis was identified in all patients, involving 114 (85%) of the 134 lobes and 210 (52%) of the 406 segments studied. Other bronchial abnormalities such as dilated and totally occluded bronchi (11 patients), air-fluid levels within dilated bronchi (five patients), bronchial wall thickening (10 patients) and parallel-line shadows (seven patients) were also observed. Parenchymal abnormalities, which had a predilection for upper lobes, included consolidation in 10 (43%) patients, collapse in four (17%) patients and parenchymal scarring in 19 (83%) patients. A total of six cavities were seen in three (13%) patients, and an emphysematous bullae was detected in one (4%) patient. The pleura was involved in 10 (43%) patients. Ipsilateral pleural effusion with collapse was observed in one patient, while in nine other patients, parenchymal, lesions extended up to the pleura. Concomitant allergic Aspergillus sinusitis (AAS) was also detected in three (13%) of the 23 patients. Computed tomography of the thorax in patients with ABPA provides a sensitive method for the assessment of bronchial, parenchymal and pleural abnormalities, and should constitute a part of the diagnostic work of the disease.

The microbial exposure associated with health complaints in moldy houses consists of a heterogeneous group of components, including both living and dead bacteria, fungi, and their metabolites and active compounds. However, little is known about the interactions between different microbes and their metabolites, although the cytotoxicity and inflammatory potential of certain individual microbes have been reported. In this study, we investigated the inflammatory responses of mouse RAW264.7 macrophages after exposure to six indoor air microbes (Aspergillus versicolor, Penicillium spinulosum, Stachybotrys chartarum, Bacillus cereus, Mycobacterium terrae, and Pseudomonas fluorescens) alone and together with the actinomycete Streptomyces californicus. The production of nitric oxide, levels of the proinflammatory cytokines tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6), and cytotoxicity were measured. The coexposure to Sta. chartarum and Str. californicus caused a synergistic increase in the production of IL-6 but not other cytokines. In further experiments, the metabolites from Sta. chartarum or from closely related fungi (atranones B and E, satratoxin G, trichodermin, 7-alpha-hydroxytrichodermol, staplabin, and SMTP-7) and the known fungal toxins sterigmatocystin, citrinin, and ochratoxin A were each tested with Str. californicus. The testing revealed a synergistic response in TNF-alpha and IL-6 production after coexposure to Str. californicus with both trichodermin and 7-alpha-hydroxytrichodermol. Finally, the synergistic inflammatory response caused by Str. californicus and trichodermin together was studied by analyzing for the presence of nuclear factor-kappa-B (NF-kappa-B) in nuclear extracts of the exposed cells. The exposure to Str. californicus induced the binding of NF-kappa-B proteins to the NF-kappa-B consensus sequence as well as to the natural NF-kappa-B site of the IL-6 promoter. Adding trichodermin to the exposure did not increase the DNA binding.

(N.B. The Aspergillus website used to maintain a bibliographic database which was compiled from Medline and Web of Science (GRAsp), but as all users now have access to the former free of charge via the NCBI website and most will have access to Web of Science via their own libraries this resource is currently not being updated. It contains papers dating up to 7th October 2002. Search the GRASp Database here.)