Hyphal Fragments Research Articles

Fungal populations in the bedroom dust of children in Havana, Cuba, and its relationship with environmental conditions.

The study of the fungal community composition in house dust is useful to assess the accumulative exposure to fungi in indoor environments. The objective of this research was to characterize the fungal diversity of house dust and its association with the environmental conditions of bedrooms. For this, the dust was collected from 41 bedrooms of children between the ages of 8 and 9 with a family history of asthma, residents of Havana, Cuba. The fungal content of each sample was determined by two methods: plate culture with malt extract agar and by direct microscopy. An ecological analysis was carried out from the fungal diversity detected. To describe the factors associated with the fungi detected, bivariate logistic regression was used. Through direct microscopy, between 10 and 2311 fragments of hyphae and spores corresponding mainly to Cladosporium, Coprinus, Curvularia, Aspergillus/Penicillium, Xylariaceae, and Periconia were identified. Through the culture, 0-208 CFU were quantified, where Aspergillus, Cladosporium, and Penicillium predominated. The culturability evidenced the differences between the quantification determined by both methods. A positive relationship was found between the type of cleaning of the furniture, the presence of trees in front of the bedroom, indoor relative humidity, indoor temperature, the presence of air conditioning, and natural ventilation with specific spore types and genera. The use of two different identification methods allowed to detect a greater fungal diversity in the residences evaluated. Monitoring the exposure to these fungal allergens in childhood can help to prevent sensitization in the allergic child, the development of asthma, and other respiratory diseases.

Indigenous Fungivorous Nematodes Affect the Biocontrol Efficacy of Trichoderma harzianum through Reducing the Hyphal Density.

Indigenous fungus-feeding nematodes may adversely affect the growth and activity of introduced biocontrol fungi. Alginate pellets of the biocontrol fungus Trichoderma harzianum ThzID1-M3 and sclerotia of the fungal plant pathogen Sclerotinia sclerotiorum were added to nonsterile soil at a soil water potential of -50 or -1,000 kPa. The biomass of ThzID1-M3, nematode populations, and extent of colonization of sclerotia by ThzID1-M3 were monitored over time. The presence of ThzID1-M3 increased the nematode population under both moisture regimes (p < 0.05), and fungivores comprised 69-75% of the nematode population. By day 5, the biomass of ThzID1-M3b and its colonization of sclerotia increased and were strongly correlated (R2 = 0.98), followed by a rapid reduction, under both regimes. At -50 kPa (the wetter of the two environments), fungal biomass and colonization by ThzID1-M3 were less, in the period from 5 to 20 days, while fungivores were more abundant. These results indicate that ThzID1-M3 stimulated the population growth of fungivorous nematodes, which in turn, reduced the biocontrol ability of the fungus to mycoparasitize sclerotia. However, colonization incidence reached 100% by day 5 and remained so for the experimental period under both regimes, although hyphal fragments disappeared by day 20. Our results suggest that indigenous fungivores are an important constraint for the biocontrol activity of introduced fungi, and sclerotia can provide spatial refuge for biocontrol fungi from the feeding activity of fungivorous nematodes.

Aspergillus derived mycotoxins in food and the environment: Prevalence, detection, and toxicity.

Aspergillus species are the paramount ubiquitous fungi that contaminate various food substrates and produce biochemicals known as mycotoxins. Aflatoxins (AFTs), ochratoxin A (OTA), patulin (PAT), citrinin (CIT), aflatrem (AT), secalonic acids (SA), cyclopiazonic acid (CPA), terrein (TR), sterigmatocystin (ST) and gliotoxin (GT), and other toxins produced by species of Aspergillus plays a major role in food and human health. Mycotoxins exhibited wide range of toxicity to the humans and animal models even at nanomolar (nM) concentration. Consumption of detrimental mycotoxins adulterated foodstuffs affects human and animal health even trace amounts. Bioaerosols consisting of spores and hyphal fragments are active elicitors of bronchial irritation and allergy, and challenging to the public health. Aspergillus is the furthermost predominant environmental contaminant unswervingly defile lives with a 40-90 % mortality risk in patients with conceded immunity. Genomics, proteomics, transcriptomics, and metabolomics approaches useful for mycotoxins' detection which are expensive. Antibody based detection of toxins chemotypes may result in cross-reactivity and uncertainty. Aptamers (APT) are single stranded DNA (ssDNA/RNA), are specifically binds to the target molecules can be generated by systematic evolution of ligands through exponential enrichment (SELEX). APT are fast, sensitive, simple, in-expensive, and field-deployable rapid point of care (POC) detection of toxins, and a better alternative to antibodies.

The study of the effects of airborne fungal spores in allergic and pathogenic infections in Akoko environment, Ondo State, Nigeria

Fungal spores and hyphal fragments have been associated with out-door allergens and constitute human, animal and plant pathogens with long history of epidemiology. Airborne fungal spores of Akoko environment during the months of October 2016 to September 2017 were trapped and analyzed palynologicaly to determine the genera with allergic and pathogenic implications. Very high concentrations of these aerospora were documented. Out of 35 fungal spore type identified, the most commonly documented genera were species of Nigrospora, Endophragmiella, Ustilago, Botryodiplodia, Curvularia, Pithomyces, Corynespora and Venturia among others. The availability of these airborne fungal spore types is not only a reflection of their degree of abundance in the atmosphere, but an indication of the availability of host plants and other spore sources in the region. Statistical analysis shows that there was significant difference in the mean monthly fungal spore recorded. Multiple comparisons (using DMRT) showed that the mean fungal spores recorded in the month of October was significantly different (P&lt;0.05) from that recorded in the month of July but not significantly different from those recorded for other months. Seasonal variation showed that the highest mean monthly fungal spore abundance were more from June - July and October - December due to higher sporulation activities by the fungi. This study would provide relevant information that could be useful in monitoring the frequency and intensity of fungal allergies and other pathogenic disease conditions of plants, animals and humans in the study environment and proffer adequate measures for safety health and environment.

Blastomycosis in Africa and the Middle East: A Comprehensive Review of Reported Cases and Reanalysis of Historical Isolates Based on Molecular Data.

BackgroundBlastomycosis has been reported from countries in Africa and the Middle East, but a decades-long debate has persisted regarding whether this is the same disease known in North America and caused by Blastomyces dermatitidis and Blastomyces gilchristii.MethodsWe reviewed published cases of human and veterinary blastomycosis from Africa and the Middle East. We abstracted epidemiological and clinical features of cases, including sites of disease, diagnosis, management, outcomes, and, where available, genetic and antigenic typing of case isolates. In addition, we sequenced nucleic acids from 9 clinical isolates from Africa deposited in global collections as B. dermatitidis; for 5, we sequenced the internal transcribed spacer regions, and for the other 4 we sequenced the whole genomes.ResultsWe identified 172 unique human patients with blastomycosis, including 159 patients from 25 African countries and 12 patients from 5 Middle Eastern countries, and also identified 7 reports of veterinary blastomycosis. In humans, cutaneous disease predominated (n = 100/137, 73%), followed by pulmonary (n = 73/129, 57%) and osteoarticular involvement (n = 61/128, 48%). Unusual direct microscopy/histopathological presentations included short hyphal fragments in tissues (n = 23/129, 18%). There were 34 genotyped case isolates that comprised 4 species: Blastomyces percursus (n = 22, 65%), from 8 countries throughout all regions; Blastomyces emzantsi (n = 9, 26%), from South Africa; B. dermatitidis (n = 1, 3%), from the Democratic Republic of Congo; and B. gilchristii (n = 2, 6%), from South Africa and Zimbabwe.ConclusionsBlastomycosis occurs throughout Africa and the Middle East and is caused predominantly by B. percursus and, at least in South Africa, B. emzantsi, resulting in distinct clinical and pathological patterns of disease.

Allergenic fungal spores and hyphal fragments in the aerosol of Havana, Cuba

Fungal spores have a recognized allergenicity, but in recent years, fungal fragments have also been reported as inducers of Type I allergy. However, airborne hyphae are scarcely studied in tropical regions. The objective of this research was to analyze the fungal composition of the Havana aerosol during 2017 and 2018, emphasizing the presence of hyphae fragments. Air sampling was performed using a Lanzoni VPPS-2000 sampler. The fungal propagules collected were identified and counted following the recommendations of the Spanish Aerobiology Network in two longitudinal transepts of each daily slides. In 2017, the spore count and hyphae count were higher than in 2018 (108,607 spores and 3822 fungal fragments vs. 40,896 spores and 2268 fungal fragments). Cladosporium was the most abundant spore (77.2–76.6%), predominating in the month of May. Leptosphaeria ascospores were identified at lower levels (16.2–17.9%) but also abundant during May. The behavior of the hyphal fragments does not show great variations throughout the year. The contribution of this component to the aerosol ranged between 3.4 and 5.3% in 2017 and 2018, respectively. The intradiurnal periodicity showed a diurnal pattern for Cladosporium and nocturnal for Leptosphaeria, while the hyphae pattern does not show great variations. The temperature and relative humidity correlated with the concentration of the detected airborne fungi propagules. The composition of the fungal aerosol in Havana during the 2 years was characterized, including both spores and hyphal fragments, since both structures can be related to respiratory allergy pathologies.

Subchronic inhalation of Aspergillus versicolor conidia leads to sustained innate immune responses and is associated with irreversible remodeling of pulmonary arterial tissue following recovery

Abstract Aspergillus versicolor is an environmentally ubiquitous fungal species that is particularly abundant in environments with water infiltration. Respiration of fungal products, including conidia, hyphal fragments, mycotoxins, and other secondary metabolites may cause adverse pulmonary health effects including asthma and allergy. In the present study, pulmonary immune responses in B6C3F1 mice were examined following 1, 2, 4, 8, and 13 weeks of repeated respiratory challenge to 3×105A. versicolor conidia. Increased alveolar macrophages, inflammatory monocytes, neutrophils, and eosinophils, which peaked between 4 and 8 weeks, were detected in the lungs of mice exposed to viable conidia. Type 2 innate lymphoid cells (ILC2s) peaked between 8 and 13 weeks compared to total T cells which increased between 2 and 8 weeks and decreased at 13 weeks. Protein concentrations of the Th2 cytokines IL4, IL5, and IL13 were highest in bronchoaveolar lavage fluid of exposed mice following 4 weeks and exhibited a time-dependent reduction at 8 and 13 weeks. Inhalation of conidia for 13 weeks led to goblet cell hyperplasia, vascular wall thickening, and perivascular inflammation. Finally, mixed perivascular inflammation and smooth muscle hypertrophy were sustained at 4 weeks post-exposure. These data indicate that exposure to A. versicolor elicits a Th2-biased immune response that is driven by innate cell populations and is associated with the induction of remodeling of the pulmonary vasculature.

Dynamic Surface Proteomes of Allergenic Fungal Conidia.

Fungal spores and hyphal fragments play an important role as allergens in respiratory diseases. In this study, we performed trypsin shaving and secretome analyses to identify the surface-exposed proteins and secreted/shed proteins of Aspergillus fumigatus conidia, respectively. We investigated the surface proteome under different conditions, including temperature variation and germination. We found that the surface proteome of resting A. fumigatus conidia is not static but instead unexpectedly dynamic, as evidenced by drastically different surface proteomes under different growth conditions. Knockouts of two abundant A. fumigatus surface proteins, ScwA and CweA, were found to function only in fine-tuning the cell wall stress response, implying that the conidial surface is very robust against perturbations. We then compared the surface proteome of A. fumigatus to other allergy-inducing molds, including Alternaria alternata, Penicillium rubens, and Cladosporium herbarum, and performed comparative proteomics on resting and swollen conidia, as well as secreted proteins from germinating conidia. We detected 125 protein ortholog groups, including 80 with putative catalytic activity, in the extracellular region of all four molds, and 42 nonorthologous proteins produced solely by A. fumigatus. Ultimately, this study highlights the dynamic nature of the A. fumigatus conidial surface and provides targets for future diagnostics and immunotherapy.

Characterization and pro-inflammatory potential of indoor mold particles.

A number of epidemiological studies find an association between indoor air dampness and respiratory health effects. This is often suggested to be linked to enhanced mold growth. However, the role of mold is obviously difficult to disentangle from other dampness-related exposure including microbes as well as non-biological particles and chemical pollutants. The association may partly be due to visible mycelial growth and a characteristic musty smell of mold. Thus, the potential role of mold exposure should be further explored by evaluating information from experimental studies elucidating possible mechanistic links. Such studies show that exposure to spores and hyphal fragments may act as allergens and pro-inflammatory mediators and that they may damage airways by the production of toxins, enzymes, and volatile organic compounds. In the present review, we hypothesize that continuous exposure to mold particles may result in chronic low-grade pro-inflammatory responses contributing to respiratory diseases. We summarize some of the main methods for detection and characterization of fungal aerosols and highlight in vitro research elucidating how molds may induce toxicity and pro-inflammatory reactions in human cell models relevant for airway exposure. Data suggest that the fraction of fungal hyphal fragments in indoor air is much higher than that of airborne spores, and the hyphal fragments often have a higher pro-inflammatory potential. Thus, hyphal fragments of prevalent mold species with strong pro-inflammatory potential may be particularly relevant candidates for respiratory diseases associated with damp/mold-contaminated indoor air. Future studies linking of indoor air dampness with health effects should assess the toxicity and pro-inflammatory potential of indoor air particulate matter and combined this information with a better characterization of biological components including hyphal fragments from both pathogenic and non-pathogenic mold species. Such studies may increase our understanding of the potential role of mold exposure.

Particle size distribution of the major Alternaria alternata allergen, Alt a 1, derived from airborne spores and subspore fragments

Fungal fragments are abundant immunoreactive bioaerosols that may outnumber the concentrations of intact spores in the air. To investigate the importance of Alternaria fragments as sources of allergens compared to Alternaria spores, we determined the levels of Alternaria spores and Alt a 1 (the major allergen in Alternaria alternata spores) collected on filters within three fractions of particulate matter (PM) of different aerodynamic diameter: (1) PM>10, (diameter>10 μm); (2) PM2.5-10 (2.5–10μm); (3) PM2.5 (0.12–2.5 μm). The airborne particles were collected using a three stage high-volume ChemVol cascade impactor during the Alternaria sporulation season in Poznań, Poland (30 d between 6 July and 22 September 2016). The quantification of Alt a 1 was performed using the enzyme-linked immunosorbent assay. High concentrations of Alt a 1 were recorded during warm and dry d characterized by high sunshine duration, lack of clouds and high dew point values. Atmospheric concentrations of Alternaria spores correlated significantly (r = 0.930, p < 0.001) with Alt a 1 levels. The highest Alt a 1 was recorded in PM2.5-10 (66.8 % of total Alt a 1), while the lowest in PM2.5 (<1.0 %). Significantly more Alt a 1 per spore (>30 %) was observed in PM2.5-10 than in PM>10. This Alt a 1 excess may be derived from sources other than spores, e.g. hyphal fragments. Overall, in outdoor air the major source of Alt a 1 are intact Alternaria spores, but the impact of other fungal fragments (hyphal parts, broken spores, conidiophores) cannot be neglected, as they may increase the total atmospheric Alt a 1 concentration.

Sonicated extracts from the Quorn fermentation co-product as oil-lowering emulsifiers and foaming agents

This study assessed the impact of sonication on the structure and properties of a functional extract (retentate 100 or R100) from the Quorn fermentation co-product (centrate). In a previous study, we reported that the R100 fraction displayed good foaming, emulsifying and rheological properties. Sonication of a R100 solution led to the breakdown of the large hyphal structures characteristic of this extract into smaller fragments. Foams prepared with sonicated R100 displayed a higher foaming ability than with untreated R100 and a high foam stability but lower than untreated R100 ones. Oil-in-water emulsions prepared with sonicated R100 displayed smaller oil droplet size distributions than with untreated R100. Confocal micrographs suggested that small fungal fragments contributed to the stabilisation of oil droplets. 50% oil-reduced R100 emulsions were prepared by mixing R100 emulsions (untreated or sonicated) with a sonicated R100 solution at a 1:1 ratio. Smaller oil droplet size distributions were reported for the oil-reduced emulsions. These results showed that the addition of small hyphal fragments or surface-active molecules and molecular aggregates released during sonication contributed to the formation and stabilisation of smaller oil droplets. This study highlighted the potential to modulate the structure, emulsifying and foaming properties of functional extracts from the Quorn fermentation co-product by sonication and the potential of these extracts as oil-lowering agents in emulsion-based products through the reduction of oil droplet size and their stabilisation.Graphical abstract

Competitive saprophytic ability of the hypovirulent isolate QT5-19 of Botrytis cinerea and its importance in biocontrol of necrotrophic fungal pathogens

This study determined the competitive saprophytic ability (CSA) of the hypovirulent isolate QT5-19 of Botrytis cinerea on potato dextrose agar (PDA) at 20 °C. Meanwhile, importance of the QT5-19 CSA in biocontrol against virulent isolates of B. cinerea and Sclerotinia sclerotiorum (a close relative of B. cinerea), and the mechanisms for the QT5-19 CSA were elucidated. The results showed that QT5-19 had higher CSA than the virulent isolates 08168 (B. cinerea) and EP-1PNA367 (S. sclerotiorum) on potato dextrose agar. The hyphal fragments of QT5-19 exhibited an effective suppression against infection of leaves of oilseed rape by the hyphae of the two virulent fungal pathogens through competition. QT5-19 was detected to be able to produce volatile organic compounds (VOCs) with antifungal activity against B. cinerea and S. sclerotiorum, whereas the VOCs from the virulent isolate RoseBc-3 of B. cinerea had no detectable antifungal activity. The QT5-19 VOCs effectively reduced disease severity of strawberry fruit rot caused by two virulent fungal pathogens. These results suggest that QT5-19 may achieve success of competition through extensive mycelial growth and production of antifungal volatiles. This study provided an example of using hypovirulent isolates to control virulent isolates of B. cinerea and S. sclerotiorum.

Uji Efektivitas Inokulum Fungi Mikoriza Arbuskula Terhadap Pertumbuhan Bibit Jati (Tectona Grandis Linn. F)

Arbuscular mycorrhizal fungi is a phylum of Glomeromycota. Arbuscular mycorrhizal fungi (AMF) propagule are spores, mycor-rhizal fungal hyphae and infected root fragments. The aims of this research were to analyze the effectivity of root inoculum of AMF to enhance teak (Tectona grandis Linn F.) seedling growth. The research was used complete randomized design (CRD)-split plot design. The main plot was root inoculum of AMF, sub plot is a media sterilization and media is not sterilized. The results showed that root inoculum of AMF and media effectively improved teak growth, especially in height, diameter, and shoot dry weight. Root inoculum of AMF is able to be used as the source of inoculum for the growth teak seedling. Fresh inoculum was found to be better than root inoculum stored at room temperature and root inoculum stored at refrigerator temperature (5°C). Storage of root inocu-lum at room temperature and refrigerator temperature (5°C) for two weeks decreased the effectiveness of inoculum. Type of mixed inoculum and inoculum of Acaulospora sp. root resulted in better growth compared with G. clarum root inoculum.

In vitro and in vivo characterization of two nonsporulating Aspergillus fumigatus clinical isolates from immunocompetent patients

Aspergillus fumigatus is a pathogenic fungus responsible for invasive aspergillosis (IA). Typically, it can produce abundant conidia to survive and spread. The infection by A. fumigatus usually occurs in immunocompromised patients due to failed clearance of inhaled conidia. However, the incidence of aspergillosis in immunocompetent hosts has been increasing, the pathogenesis of which is still unknown. Our team previously obtained two clinical nonsporulating A. fumigatus isolates from non-immunocompromised patients, which only have the form of hyphae. This present study demonstrated the in vitro and in vivo characteristics of the two nonsporulating A. fumigatus isolates and verified that their conidiation defects are associated to abolished expression of the sporulation-related central regulatory pathway brlA gene. In addition, we confirmed the mutation site of brlA gene (c.657_660delTCCT) contributes to the nonsporulating phenotype in one clinical isolate. Plate assay showed that the two nonsporulating isolates have a similar resistance to antifungal drugs, cell wall disturbing substances, and oxidative stress compared with the wild-type reference Af293. Most important of all, we employed an immunocompetent mouse model to mimic the pathogenesis of pulmonary aspergillosis in non-immunocompromised patients. It revealed that the hyphae of two nonsporulating isolates and Af293 have similar virulence in immunocompetent hosts. Interestingly, the hyphae fragments of Af293 but not conidia are able to induce invasive aspergillosis in immunocompetent mice. In conclusion, our study indicate that the form of hyphae may play a dominant causative role in pulmonary aspergillosis of immunocompetent hosts rather than conidia.

Richness of Lichens Consumed by Constrictotermes cyphergaster in the Semi-arid Region of Brazil

The consumption of lichens by Constrictotermes cyphergaster termites is suggested in the literature, but not yet with concrete evidence. We examined the use and richness of lichens consumed by C. cyphergaster during both the dry and rainy seasons in a semiarid environment in northeastern Brazil by monitoring the foraging of five termite colonies for ten consecutive days during each period. Twenty-nine species of corticolous lichens were consumed by C. cyphergaster, with seasonal variations in the richness of their ingestion. Chrysothrix xanthine, Pertusaria flavens, and Dirinaria confluens were the lichen species most consumed. TLC analyzes of termite gut contents revealed twelve secondary lichen compounds ingested in both seasons, while staining showed fragments of fungal hyphae, green algae, and typical lichen spores. This study represents the first systematic survey of the abundances of lichens that compose the diet of C. cyphergaster and indicates the seasonal selectivity of that resource related to the chemical compositions of the lichen stalks.

Pro-inflammatory responses induced by A. fumigatus and A. versicolor in various human macrophage models

ABSTRACTExposure to mold-contaminated indoor air has been associated with various respiratory diseases, and there is a need for experimental data to confirm these associations. The pro-inflammatory properties of well-characterized aerosolized spores and hyphal fragments from Aspergillus fumigatus and Aspergillus versicolor were examined and compared using various human macrophage cell models including phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophages (THP-1 Ma), primary peripheral blood monocyte-derived macrophages (MDM), and primary airway macrophages (AM) from induced sputum. X-ray treated samples of the two mold species induced different responses with A. fumigatus displaying the most potent induction of pro-inflammatory responses. While hyphal fragments from A. fumigatus were more potent than spores, similar responses were produced by the two growth stages of A. versicolor. THP-1 Ma was the most sensitive model releasing a broad range of cytokines/chemokines. MDM exhibited a similar cytokine/chemokine profile as THP-1 Ma, except for a low-quantity release of interleukin-1β (IL-1β). In contrast, AM appeared to be nonresponsive and yielded a different pattern of pro-inflammatory markers. Toll-like receptor (TLR)4, but also to a certain degree TLR2, was involved in several responses induced by spores and aerosolized hyphal fragments of A. fumigatus in MDM. Taken together, MDM seems to be the most promising experimental macrophage model.Abbreviations: AF: A. fumigatus, Aspergillus fumigatus; AV: A. versicolor, Aspergillus versicolor; AM: Airway Macrophage; CBA: Cytometric Bead Array; CD: Cluster of Differentiation; DTT: dithiothreitol; ELISA: Enzyme Linked Immunosorbent Assay; FBS: fetal bovine serum; GM-CSF: Granulocyte macrophage colony-stimulating factor; IL-1β: Interleukin-1beta; MDM: Monocyte-Derived Macrophages; NF-κB: Nuclear Factor kappa light chain enhancer of activated B cells; NLR: NOD-like Receptor; PAMP: Pathogen Associated Molecular Pattern; PMA: Phorbol 12-myristate 13-acetate; PRR: Pattern Recognition Receptor; THP-1: Human leukemia monocyte cell line; TLR: Toll-like Receptor; TNF-α: Tumor Necrosis Factor- alpha

Pro-Inflammatory Responses in Human Bronchial Epithelial Cells Induced by Spores and Hyphal Fragments of Common Damp Indoor Molds.

Damp indoor environments contaminated with different mold species may contribute to the development and exacerbation of respiratory illnesses. Human bronchial epithelial BEAS-2B cells were exposed to X-ray treated spores and hyphal fragments from pure cultures of Aspergillus fumigatus, Penicillum chrysogenum, Aspergillus versicolor and Stachybotrys chartarum. Hyphal fragments of A. fumigatus and P. chrysogenum induced expression and release of the pro-inflammatory cytokine interleukin (IL)-6 and the chemokine IL-8, while none of the other hyphal preparations had effects. Hyphal fragments from A. fumigatus and P. chrysogenum also increased the expression of IL-1α, IL-1β and tumor necrosis factor (TNF)-α, but these cytokines were not released. X-ray treated spores had little or no inflammatory potential. Attenuating Toll-like receptor (TLR)-2 by blocking antibodies strongly reduced the A. fumigatus and P. chrysogenum hyphae-induced IL-6 and IL-8 release, whereas TLR4 antagonist treatment was without effects. Untreated A. fumigatus spores formed hyphae and triggered expression of pro-inflammatory genes with similarities to the effects of hyphal fragments. In conclusion, while X-ray treated spores induced no pro-inflammatory responses, hyphal fragments of A. fumigatus and P. chrysogenum enhanced a TLR2-dependent expression and release of IL-6 and IL-8.

The role of occupational Aspergillus exposure in the development of diseases.

Aspergillus spp. have a high nutritional versatility and good growth on a large variety of construction materials. They also colonize soil or food, but decaying vegetation is their primary ecological niche. Therefore, exposure to fungi may occur at home, during hospitalization, during specific leisure activities, or at the workplace. The development of Aspergillus infections depends on the interplay between host susceptibility and the organism. Environments with high counts of fungal elements (conidia, hyphal fragments and others), high levels of bioarerosols, and elevated concentrations of mycotoxins or other volatile organic compounds should be considered as potential hazards, since they may present a risk to the exposed person. Rural tasks as well as work related to wood and food industries, poultries, swineries, waste handling plants, and other occupational environments involving contaminated organic material are among the ones posing higher respiratory risks to the workers. This paper presents a review of several studies related to occupational and indoor exposure to Aspergillus, potential health effects related to that exposure, and associated exposure assessment procedures.

First Report of Neoscytalidium dimidiatum Causing Root Rot in Sweet Potato in Brazil

In January 2018, a large number of tuberous roots of sweet potato were lost in a production field in Jaiba, State of Minas Gerais, Brazil. Immediately after harvest, the roots showed dark spots on the surface, extending to the center, causing an internal, brown to black necrosis. Two symptomatic roots (cultivar Canadense) from different parts of the field were subjected to fungus isolation by removal of fragments between symptomatic and healthy tissue, followed by surface sterilization in 70% ethanol and then in sodium hypochlorite (1%) for 1 and 3 min, respectively, rinsing in sterile water, and incubation in PDA plates for 25°C in the dark. A gray to black, fast-growing fungus with abundant arthroconidia in aerial mycelia was isolated from all samples after 4 days of incubation. Hyphal tips were excised and transferred to new PDA plates, and two pure cultures (isolates) were obtained. Based on these characteristics, the fungus was identified as Neoscytalidium. For morphological analysis, culture sporulation was induced as described by Machado et al. (2014). Microscopic examination of the fungal structures identified arthroconidia with one to two septa, released by hyphal fragmentation, 4.2 to 9.5 × 3.2 to 5.3 μm, and a pycnidial synanamorph with hyaline, ellipsoid to nearly fusiform conidia, 7.4 to 12.7 × 4.2 to 6.3 μm. The morphological characteristics were similar to Neoscytalidium dimidiatum (Phillips et al. 2013). To confirm species identification, genomic DNA was extracted, and sequences of the internal transcribed spacer of the rDNA and translation elongation factor 1-α (TEF1-α) were obtained (Machado et al. 2014) and deposited in GenBank (accession nos. MH636327, MH636328, MH349427, and MH349428, respectively). According to a BLAST search, the TEF1-α sequences showed 99% identity with N. dimidiatum (accession no. KF553902). A combined phylogenetic tree obtained by Bayesian inference using MrBayes version 3.1.1 (Ronquist and Huelsenbeck 2003) grouped the isolates within the N. dimidiatum clade, confirming the species identification. One representative isolate (URM 7888) was deposited in the culture collection “Micoteca URM Profa. Maria Auxiliadora Cavalcanti” at the Universidade Federal de Pernambuco (Recife, Brazil). The pathogenicity test was performed by inoculating asymptomatic roots (cultivar Canadense), previously sterilized on the surface with 0.5% sodium hypochlorite and unwounded or wounded with a sterile scalpel at two equidistant points, with conidia suspension. Arthroconidia suspension (20 μl, 2.4 × 10⁶ conidia/ml) obtained from 7-day-old colonies was pipetted onto the inoculation sites. Sterile distilled water was used for the control instead of inoculum. Five roots were used for each treatment. The inoculated roots were maintained in plastic boxes containing moistened paper towels at approximately 25°C for 15 days. After 7 days, it was possible to observe initial symptoms of internal brown to black rot, which increased in size after 15 days. The fungus was reisolated, and pathogenicity was confirmed. The control and unwounded roots remained asymptomatic. In Brazil, N. dimidiatum has been reported causing collar and root rot in physic nut (Machado et al. 2012), black root rot in cassava (Machado et. al., 2014), and dieback in mango (Marques et al. 2013). To our knowledge, this is the first report of N. dimidiatum causing root rot of sweet potato in Brazil.

RESEARCH OF EFFECT OF DPEI-PROCESSING OF SHIITAKE FRUIT BODY ON PHYSICAL AND MECHANICAL PROPERTIES OF MUSHROOM SUSPENSION

The use of discrete-pulse energy input (DPEI) mechanisms in various industries has become a reliable tool for the intensification of heat and mass transfer processes in various technological lines and reduction of specific energy consumption. The study of structural transformations in heterogeneous systems under influence of mechanisms of DPEI opens up new possibilities for their use as evidenced by this article. Under certain conditions it is possible to prepare a mushroom suspension with specified characteristics for drying and enhance medicinal properties of the obtained powder product while retaining all valuable components of feedstock.&#x0D; The article presents the results of research of DPEI-processing effect of the shiitake mushroom fruit body on the on physical and mechanical properties and structural characteristics of the mushroom suspension. The influence of hydro module, temperature of the suspension and the layout of the working bodies of the rotor-pulse apparatus (RPA) on its dynamic viscosity was studied and the possibility of reducing viscosity by 2-3 times is shown. An analysis of mushroom suspension microstructure has showed that with a certain layout of the working bodies of the RPA it is possible to control the degree of dispersion of particles and change the spatial structure of the aggregates in the volume of the dispersion medium. It is determined that self-organization of spatial aggregates from individual hyphae in such suspensions occurs over time. Moreover, the smaller the size of hyphae (≤ 25 microns after the RPA of the first version of the arrangement: rotor-stator-rotor) are, the larger the size of the spatial aggregates are formed. After the RPA with the second layout option, the fragments of hyphae had sizes ≥ 50 μm, but the dimensions of the spatial aggregates were three times smaller.&#x0D; It is found that after three times passing of the mushroom suspension through the RPA and its subsequent treatment in the cavitation device, the dynamic viscosity of the suspension is reduced by 20%.&#x0D; Confirmation of the the effectiveness of the DPEI-mechanisms in obtaining mushroom suspension is that due to the hydromechanical destruction of the polysaccharide structures of the chitin-glucan complex of the shiitake mushroom the content of the bioavailable complex of water-soluble oncostatic and immunoregulatory polysaccharides in the powder obtained by drying the mushroom suspension in an experimental spray dryer increased 6 times. References 13, figures 6.