Toxigenic molds in water-damaged buildings: dechlorogriseofulvins from Memnoniella echinata

Three new griseofulvin derivatives from Aureobasidium pullulans

Three new griseofulvin derivatives, griseofulvinoside A-C (1-3), were isolated from the ethyl acetate extract of the solid fermentation product of Aureobasidium pullulans. Their structures were elucidated based on extensive spectroscopic data analysis of MS, 1D and 2D NMR. The antifungal activities of new compounds were evaluated against four phytopathogenic fungi in vitro, and all test compounds demonstrated inhibitory effects. Among them, compound 2 exhibited the most potent activities against the four selected phytopathogenic fungi with inhibitory rates ranging from 40.2 to 75.8% at 0.2 mg/mL.

Polyketides from the fungus Pochonia chlamydosporia and their bioactivities

Three previously undescribed griseofulvin derivatives, namely pochonichlamydins A-C, one small polyketide, namely pochonichlamydin D, together with nine known compounds, have been isolated from cultures of the fungus Pochonia chlamydosporia. Their structures with absolute configurations were elucidated on the basis of extensive spectrometric methods and single-crystal X-ray diffraction. Dechlorogriseofulvin and griseofulvin exhibited inhibitory activities against Candida albicans at the concentration of 100 μM, with inhibition rates of 69.1% and 56.3%, respectively. Meanwhile, pochonichlamydin C showed mild cytotoxicity against the human cancer MCF-7 cell line with an IC₅₀ value of 33.1 μM.

Antifungal polyketides from the marine-derived fungus Nigrospora sp. MG36-1

Three new polyketides, a griseofulvin derivative 1, a hydroanthraquinone derivative 8 and a pyranolactone derivative 10, together with eight known compounds (2-7, 9 and 11), were isolated from the marine-derived fungus Nigrospora sp. MG36-1. The structures of the three new compounds were unambiguously determined by nuclear magnetic resonance (NMR), mass spectrometry, ¹³C NMR calculation in combination with DP4+ and ECD calculations. The antitumor, antibacterial and antifungal activities of the compounds 1-9 were evaluated in vitro. Compound 1 showed antibacterial activity against Acinetobacter baumannii with MIC 42.5 μg/mL. Compounds 1 and 8 exhibited antifungal activity against Candida albicans with MICs 21.5 μg/mL and 17.5 μg/mL, respectively.

Antiparasitic Meroterpenoids Isolated from Memnoniella dichroa CF-080171

Memnoniella is a fungal genus from which a wide range of diverse biologically active compounds have been isolated. A Memnoniella dichroa CF-080171 extract was identified to exhibit potent activity against Plasmodium falciparum 3D7 and Trypanosoma cruzi Tulahuen whole parasites in a high-throughput screening (HTS) campaign of microbial extracts from the Fundación MEDINA's collection. Bioassay-guided isolation of the active metabolites from this extract afforded eight new meroterpenoids of varying potencies, namely, memnobotrins C-E (1-3), a glycosylated isobenzofuranone (4), a tricyclic isobenzofuranone (5), a tetracyclic benzopyrane (6), a tetracyclic isobenzofuranone (7), and a pentacyclic isobenzofuranone (8). The structures of the isolated compounds were established by (+)-ESI-TOF high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Compounds 1, 2, and 4 exhibited potent antiparasitic activity against P. falciparum 3D7 (EC50 0.04-0.243 μM) and T. cruzi Tulahuen (EC50 0.266-1.37 μM) parasites, as well as cytotoxic activity against HepG2 tumoral liver cells (EC50 1.20-4.84 μM). The remaining compounds (3, 5-8) showed moderate or no activity against the above-mentioned parasites and cells.

Conservation of griseofulvin genes in the gsf gene cluster among fungal genomes

The polyketide griseofulvin is a natural antifungal compound and research in griseofulvin has been key in establishing our current understanding of polyketide biosynthesis. Nevertheless, the griseofulvin gsf biosynthetic gene cluster (BGC) remains poorly understood in most fungal species, including Penicillium griseofulvum where griseofulvin was first isolated. To elucidate essential genes involved in griseofulvin biosynthesis, we performed third-generation sequencing to obtain the genome of P. griseofulvum strain D-756. Furthermore, we gathered publicly available genome of 11 other fungal species in which gsf gene cluster was identified. In a comparative genome analysis, we annotated and compared the gsf BGC of all 12 fungal genomes. Our findings show no gene rearrangements at the gsf BGC. Furthermore, seven gsf genes are conserved by most genomes surveyed whereas the remaining six were poorly conserved. This study provides new insights into differences between gsf BGC and suggests that seven gsf genes are essential in griseofulvin production.

Natural Products from Octocorals of the Genus Dendronephthya (Family Nephtheidae)

In this review, 170 natural substances, including steroid, diterpenoid, sesquiterpenoid, peptide, prostaglandin, base, chlorolipid, bicyclolactone, amide, piperazine, polyketide, glycerol, benzoic acid, glycyrrhetyl amino acid, hexitol, pentanoic acid, aminoethyl ester, octadecanone, alkaloid, and a 53-kD allergenic component from octocorals belonging to genus Dendronephthya, were listed. Some of these compounds displayed potential bioactivities.

Characterization of Three Species of Sordariomycetes Isolated from Freshwater and Soil Samples in Korea

During a survey of fungal diversity in the class Sordariomycetes, 3 fungal strains, CNUFC-KMHY6-1, CNUFC-MSW24-2-11, and CNUFC-GW2S-4 were isolated from soil and freshwater samples, respectively in Korea. The strains were analyzed both morphologically and phylogenetically on the basis of internal transcribed spacer and RNA polymerase II second largest subunit gene sequences. On the basis of their morphology and phylogeny, CNUFC-KMHY6-1, CNUFC-MSW24-2-11, and CNUFC-GW2S-4 isolates were identified as Arcopilus aureus, Memnoniella echinata, and Stachybotrys sansevieriae, respectively. To the best of our knowledge, Ar. aureus and M. echinata have not been previously recorded in Korea, and this is the first report of S. sansevieriae from freshwater niche.

Antibodies to Molds and Satratoxin in Individuals Exposed in Water-Damaged Buildings

Immunoglobulin (Ig)A, IgM, and IgG antibodies against Penicillium notatum, Aspergillus niger, Stachybotrys chartarum, and satratoxin H were determined in the blood of 500 healthy blood donor controls, 500 random patients, and 500 patients with known exposure to molds. The patients were referred to the immunological testing laboratory for health reasons other than mold exposure, or for measurement of mold antibody levels. Levels of IgA, IgM, and IgG antibodies against molds were significantly greater in the patients (p < 0.001 for all measurements) than in the controls. However, in mold-exposed patients, levels of these antibodies against satratoxin differed significantly for IgG only (p < 0.001), but not for IgM or IgA. These differences in the levels of mold antibodies among the 3 groups were confirmed by calculation of z score and by Scheffé's significant difference tests. A general linear model was applied in the majority of cases, and 3 different subsets were formed, meaning that the healthy control groups were different from the random patients and from the mold-exposed patients. These findings indicated that mold exposure was more common in patients who were referred for immunological evaluation than it was in healthy blood donors. The detection of antibodies to molds and satratoxin H likely resulted from antigenic stimulation of the immune system and the reaction of serum with specially prepared mold antigens. These antigens, which had high protein content, were developed in this laboratory and used in the enzyme-linked immunosorbent assay (ELISA) procedure. The authors concluded that the antibodies studied are specific to mold antigens and mycotoxins, and therefore could be useful in epidemiological and other studies of humans exposed to molds and mycotoxins.

Griseofulvin Derivative and Indole Alkaloids from Penicillium griseofulvum CPCC 400528

A new griseofulvin derivative, 4'-demethoxy-4'-N-isopentylisogriseofulvin (1), three new indole alkaloids, 2-demethylcyclopiamide E (2), 2-demethylsperadine F (3), and clopiamine C (4), and five known metabolites (5-9) were isolated from Penicillium griseofulvum CPCC 400528. Compound 1 is the first reported griseofulvin analogue with an N-isopentane group and the first example of a naturally occurring N-containing griseofulvin analogue. Their structures and absolute configurations were elucidated through extensive spectroscopic analyses, calculated ECD, and single-crystal X-ray diffraction (Cu Kα). The possible biogenetic pathway of 1-3 was proposed. Compounds 1, 2, and 5 exhibited anti-HIV activities with IC₅₀ values of 33.2, 20.5, and 12.6 μM, respectively.

Diverse secondary metabolites produced by marine-derived fungus Nigrospora sp. MA75 on various culture media

Bioassay-guided isolation of a fungal strain Nigrospora sp. MA75, an endophytic fungus obtained from the marine semi-mangrove plant Pongamia pinnata, which was fermented on three different culture media, resulted in the isolation and identification of seven known compounds, 2, 3, and 5-9, from a medium containing 3.5% NaCl, while a new compound, 2,3-didehydro-19α-hydroxy-14-epicochlioquinone B (10) was obtained from the medium containing 3.5% NaI. In addition, two new griseofulvin derivatives, 6-O-desmethyldechlorogriseofulvin (1) and 6'-hydroxygriseofulvin (4), were isolated and identified from the rice solid medium. Dechlorogriseofulvin (2) and griseofulvin (3) were the major components in fermentation extracts of all these culture media, while compounds 1 and 4, 5 and 6, and 10 were only present in the extract of respective culture medium. The structures of these compounds were elucidated by detailed spectroscopic analysis, and the absolute configuration of 1 was determined by CD measurement. Compounds 9 and 10 exhibited antibacterial activities toward five tested bacterial strains, while compounds 5, 6, and 8 selectively inhibited MRSA, E. coli, and S. epidermidis, and compound 3 showed moderate activity against V. mali and S. solani. Moreover, compound 10 potently inhibited the growth of MCF-7, SW1990, and SMMC7721 tumor cell lines with IC(50) values of 4, 5, and 7 μg/ml, respectively.

Transformations of Griseofulvin in Strong Acidic Conditions – Crystal Structures of 2′-Demethylgriseofulvin and Dimerized Griseofulvin

The structure of griseofulvic acid, C16H15ClO6, at 100 K has orthorhombic (P21212) symmetry. It is of interest with respect to biological activity. The structure displays intermolecular O–H···O, C–H···O hydrogen bonding as well as week C–H···π and π ···π interactions. In strong acidic conditions the griseofulvin undergoes dimerization. The structure of dimerized griseofulvin, C34H32Cl2O12·C2H6O·H2O, at 100 K has monoclinic (P21) symmetry. The molecule crystallized as a solvate with one ethanol and one water molecule. The dimeric molecules form intermolecular O–H···O hydrogen bonds to solvents molecules only but they interact via week C–H···O, C–H···π, C–Cl···π and π···π interactions with other dimerized molecules.

Evaluation of settled floor dust for the presence of microbial metabolites and volatile anthropogenic chemicals in indoor environments by LC-MS/MS and GC-MS methods

This study reports on detection of a large number of biological and anthropogenic pollutants using LC-MS/MS and GC-MS technologies in settled floor dust (SFD). The latter technique was applied to obtain a general picture on the presence of microbial as well as non-microbial volatile organic compounds, whereas the targeted LC-MS/MS analysis focused on identification of species specific secondary metabolites. In the absence of moisture monitoring data the relevance of finding of stachybotrylactam and other metabolites of tertiary colonizers are confined only to accidental direct exposure to SFD. To the best of our knowledge 30 of the 71 identified volatile organic compounds (VOCs) are newly reported in SFD matrix. Coordinated application of "AMDIS and Spectconnect" was found beneficial for the evaluation and identification of prime volatile pollutants in complex environmental samples. Principal component analysis (PCA) of peak areas of 18 microbial volatile organic compounds (MVOCs) resulted in identification of nonanal as potential MVOC marker. Two more volatiles toluene and 1-tetradecanol though had discriminative influence, are not regarded as MVOC markers, considering their probable alternate origin from paints and cosmetics, respectively.

Identification of the viridicatumtoxin and griseofulvin gene clusters from Penicillium aethiopicum

Penicillium aethiopicum produces two structurally interesting and biologically active polyketides: the tetracycline-like viridicatumtoxin 1 and the classic antifungal agent griseofulvin 2. Here, we report the concurrent discovery of the two corresponding biosynthetic gene clusters (vrt and gsf) by 454 shotgun sequencing. Gene deletions confirmed that two nonreducing PKSs (NRPKSs), vrtA and gsfA, are required for the biosynthesis of 1 and 2, respectively. Both PKSs share similar domain architectures and lack a C-terminal thioesterase domain. We identified gsfI as the chlorinase involved in the biosynthesis of 2, because deletion of gsfI resulted in the accumulation of decholorogriseofulvin 3. Comparative analysis with the P. chrysogenum genome revealed that both clusters are embedded within conserved syntenic regions of P. aethiopicum chromosomes. Discovery of the vrt and gsf clusters provided the basis for genetic and biochemical studies of the pathways.

Analysis of fungal flora in indoor dust by ribosomal DNA sequence analysis, quantitative PCR, and culture

In recent years increasing attention has been given to the potential health effects of fungal exposure in indoor environments. We used large-scale sequencing of the fungal internal transcribed spacer region (ITS) of nuclear ribosomal DNA to describe the mycoflora of two office buildings over the four seasons. DNA sequencing was complemented by cultivation, ergosterol determination, and quantitative PCR analyses. Sequences of 1,339 clones were clustered into 394 nonredundant fungal operational taxonomical units containing sequences from 18 fungal subclasses. The observed flora differed markedly from that recovered by cultivation, the major differences being the near absence of several typical indoor mold genera such as Penicillium and Aspergillus spp. and a high prevalence of basidiomycetes in clone libraries. A total of 55% of the total diversity constituted of unidentifiable ITS sequences, some of which may represent novel fungal species. Dominant species were Cladosporium cladosporioides and C. herbarum, Cryptococcus victoriae, Leptosphaerulina americana and L. chartarum, Aureobasidium pullulans, Thekopsora areolata, Phaeococcomyces nigricans, Macrophoma sp., and several Malassezia species. Seasonal differences were observed for community composition, with ascomycetous molds and basidiomycetous yeasts predominating in the winter and spring and Agaricomycetidae basidiomycetes predominating in the fall. The comparison of methods suggested that the cloning, cultivation, and quantitative PCR methods complemented each other, generating a more comprehensive picture of fungal flora than any of the methods would give alone. The current restrictions of the methods are discussed.

Indoor mould development and dispersal

Indoor mould development can occur following the accumulation of free water associated with a susceptible building material. Upon entry of viable fungal propagules from outdoors, the fungus becomes attached to a susceptible substrate. Vegetative growth begins if the appropriate environmental conditions exist, the primary ones being ample free water and a susceptible substrate that can provide the necessary nutrients for fungal growth. Extracellular fungal enzymes are released into the immediate environment surrounding the fungus from which nutrients are absorbed resulting in biodeterioration of building materials. As the fungal vegetative growth expands, fungal reproductive propagules such as conidia, ascospores, basidiospores, and viable hyphal units develop that are typically carried by air currents to new sites within the indoor environment. The indoor fungal ecologic niche is a complex ecosystem where different fungal species interact among themselves and with bacteria, insects, and mites.

Optimizing a GC-MS method for screening of Stachybotrys mycotoxins in indoor environments

Presence of Stachybotrys chartarum in indoor environments has been linked to building-associated disease, however, the causative agents are unknown. Verrucarol (VER) and trichodermol (TRID) are hydrolysis products of some major S. chartarum mycotoxins, i.e. macrocyclic trichothecenes and trichodermin. We optimized gas chromatography-mass spectrometry (GC-MS) methods for detecting VER and TRID in S. chartarum-contaminated indoor environmental samples. Heptafluorobutyryl derivatives of both VER and TRID exhibited little MS fragmentation and gave much higher detection sensitivity (sub-picogram injected onto the GC column), both in GC-MS and GC-MSMS, than trimethylsilyl derivatives. Optimal detection sensitivity and specificity was achieved by combining chemical ionization and negative ion (NICI) detection with MSMS. With this method, VER and TRID were detected in building materials colonized by S. chartarum and TRID was demonstrated in dust settled in the breathing zone in a house where an inner wall was colonized. In summary, we have shown that NICI-GC-MSMS can be used to demonstrate mycotoxins in house dust in S. chartarum-contaminated dwellings.

Severe anemia owing to occult pulmonary hemorrhage: a diagnostic pitfall

The purpose of this paper is to increase the awareness about pulmonary hemorrhage as a possible cause of microcytic hypochromic anemia and to delineate diagnostic difficulties and possible pitfalls. An instructive case of anemia of unclear origin referred to our institution for a hematologic workup is presented. Microcytic hypochromic anemia owing to repeated occult alveolar hemorrhages was the only clinical sign of idiopathic pulmonary hemosiderosis in this case. The laboratory finding constellation in such cases may be misleading and may lead to misinterpretation. Awareness about this condition among pediatricians and hematologists can optimize and accelerate the diagnostic process.

Microbial Contamination in Airplane Cabins:Health Effects and Remediation

Microorganisms that affect human health are found in all indoor environments, including cabins of commercial aircraft. Those that arise from human sources can be transmitted by direct contact, droplets, or the airborne route. Infections from human sources include Influenza, Rhinovirus, SARS and tuberculosis. Transmission by the airborne route can be reduced by sterilizing the air with ultraviolet germicidal irradiation, or by diluting the contaminated air with outdoor air through ventilation. Microbes arising from environmental sources include bacteria, fungi and other organisms such as protozoa. These usually have very simple requirements for growth – water and a simple substrate such as dust. They cause health effects through direct infection rarely (one example is Legionnella), but more commonly cause immune reactions resulting in hypersensitivity or allergy mediated diseases. Environmental sources of microbial contamination are best prevented, but can be remediated through cleaning, germicidal chemicals, or ultraviolet germicidal irradiation. Airborne microbial substances including toxins, antigens and viable organisms can be removed by outdoor air ventilation or filtration. In aircraft cabins transmission of pathogens from human sources is difficult to control, but airborne transmission can be reduced through increased outdoor air ventilation or filtration. Environmental microbial contamination can, and does occur in aircraft cabins. These microbial sources are best prevented but, if detected, can be removed through cleaning or disinfection. Ultraviolet germicidal irradiation is an under-utilized technology that may be useful for sterilizing air as well as potential environmental sources.

Saliva secretory IgA antibodies against molds and mycotoxins in patients exposed to toxigenic fungi

Upper respiratory exposure to different environmental antigens results first in the activation of mucosal immunity and production of IgA antibodies in different secretions including saliva. Despite this there is no study, which addresses secretory antibodies against molds and mycotoxins. The purpose of this study was to evaluate mold-specific salivary IgA in individuals exposed to molds and mycotoxins in a water-damaged building environment. Saliva IgA antibody levels against seven different molds and two mycotoxins were studied in 40 patients exposed to molds and in 40 control subjects. Mold-exposed patients showed significantly higher levels of salivary IgA antibodies against one or more mold species. A majority of patients with high IgA antibodies against molds exhibited elevation in salivary IgA against mycotoxins, as well. These IgA antibodies against molds and mycotoxins are specific, since using molds and mycotoxins in immune absorption could reduce antibody levels, significantly. Detection of high counts of molds in water-damaged buildings, strongly suggests the existence of a reservoir of mold spores in the environment. This viable microbial activity with specific mold and mycotoxin IgA in saliva may assist in the diagnosis of mold exposure. Whether mold and mycotoxin specific IgA antibodies detected in saliva are indicative of the role of IgA antibodies in the late phase of type-1 hypersensitivity reaction or in type-2 and type-3 delayed sensitivities is a matter that warrants further investigation.

Stachybotrys chartarum: a fungus for our time

Stachybotrys chartarum, a fungus found in damp buildings and sometimes ascribed a role in building-related illnesses, produces a variety of secondary metabolites including trichothecenes, triprenylated phenolics, and a new class of diterpenoids called atranones. A related fungus, Memnoniella echinata also produces trichothecenes and the triprenylated phenolics. Herein the production of these compounds from cultures of the above are reviewed.

Mycotoxin production by indoor molds

Fungal growth in buildings starts at a water activity (a(w)) near 0.8, but significant quantities of mycotoxins are not produced unless a(w) reaches 0.95. Stachybotrys generates particularly high quantities of many chemically distinct metabolites in water-damaged buildings. These metabolites are carried by spores, and can be detected in air samples at high spore concentrations. Very little attention has been paid to major metabolites of Stachybotrys called spirocyclic drimanes, and the precise structures of the most abundant of these compounds are unknown. Species of Aspergillus and Penicillium prevalent in the indoor environment produce relatively low concentrations of mycotoxins, with the exception of sterigmatocystins that can represent up to 1% of the biomass of A. versicolor at a(w)'s close to 1. The worst-case scenario for homeowners is produced by consecutive episodes of water damage that promote fungal growth and mycotoxin synthesis, followed by drier conditions that facilitate the liberation of spores and hyphal fragments.

Indoor mold, toxigenic fungi, and Stachybotrys chartarum: infectious disease perspective

Damp buildings often have a moldy smell or obvious mold growth; some molds are human pathogens. This has caused concern regarding health effects of moldy indoor environments and has resulted in many studies of moisture- and mold-damaged buildings. Recently, there have been reports of severe illness as a result of indoor mold exposure, particularly due to Stachybotrys chartarum. While many authors describe a direct relationship between fungal contamination and illness, close examination of the literature reveals a confusing picture. Here, we review the evidence regarding indoor mold exposure and mycotoxicosis, with an emphasis on S. chartarum. We also examine possible end-organ effects, including pulmonary, immunologic, neurologic, and oncologic disorders. We discuss the Cleveland infant idiopathic pulmonary hemorrhage reports in detail, since they provided important impetus for concerns about Stachybotrys. Some valid concerns exist regarding the relationship between indoor mold exposure and human disease. Review of the literature reveals certain fungus-disease associations in humans, including ergotism (Claviceps species), alimentary toxic aleukia (Fusarium), and liver disease (Aspergillys). While many papers suggest a similar relationship between Stachybotrys and human disease, the studies nearly uniformly suffer from significant methodological flaws, making their findings inconclusive. As a result, we have not found well-substantiated supportive evidence of serious illness due to Stachybotrys exposure in the contemporary environment. To address issues of indoor mold-related illness, there is an urgent need for studies using objective markers of illness, relevant animal models, proper epidemiologic techniques, and examination of confounding factors.

Chemistry and toxicology of molds isolated from water-damaged buildings

There is increasing evidence of health risks associated with damp buildings and homes in which high levels of microbes are found. Although concerns have traditionally centered on microbial pathogens and allergenic effects, recent work has suggested that fungi pose the more serious risk. Evidence is accumulating that certain toxigenic molds are particularly a risk for human health through exposure, via inhalation, of fungal spores. Many of these fungi produce toxins (mycotoxins) some of which have been shown to cause animal and human intoxications, usually in an agricultural setting. The fungus, Stachybotrys chartarum (S. atra) is considered to be one of the more serious threats to people living and working in water-damaged buildings. This mold has a long history of being responsible for animal toxicoses, and in recent years, being associated with infant pulmonary hemosiderosis (bleeding in the lungs) of infants exposed to spores of this fungus in their homes. S. atra produces a variety of potent toxins and immunosuppressant agents, including a novel class of diterpenes (atranones) of unusual structure. More research is needed to determine the impact to health resulting from inhalation of toxigenic mold spores.

Fast methods for screening of trichothecenes in fungal cultures using gas chromatography-tandem mass spectrometry

The paper presents a fast method for trichothecene profiling and chemotaxonomic studies in species of Fusarium, Stachybotrys. Trichoderma and Memnoniella. Micro scale extracted crude Fusarium extracts were derivatised using pentafluoropropionic anhydride and analysed by gas chromatography with simultaneous full scan and tandem mass spectrometric detection. It was possible to monitor for up to four compounds simultaneous, making detection of acetyl T-2 toxin, T-2 toxin, HT-2 toxin, T-2 triol. T-2 tetraol, neosolaniol, iso-neosolaniol, scirpentriol, 4,15-diacetoxyscirpenol, 15-acetoxyscirpenol, 4-acetoxyscirpentriol, nivalenol, fusarenon-X, deoxynivalenol, 15-acetyl-deoxynivalenol and 3-acetyldeoxynivalenol possible during a 23-min GC run. A slightly modified method could detect trichothecenes produced by Stachybotrys, Memnoniella and Trichoderma, by hydrolysing crude extracts prior to derivatisation with heptafluorobuturyl imidazole. All types of derivatised extracts could be reanalysed using negative ion chemical ionisation (NICI) GC-MS for molecular mass determination and verification purposes. A retention time index could be used for correction in retention time drifts between sequences and worked both in EI+ and NICI mode.

Preliminary description of antigenic components characteristic of Stachybotrys chartarum

The objective of this study was to characterize preliminarily immunogenic components characteristic of Stachybotrys chartarum to be used later for the development of a detection method for the fungus in environmental samples. The procedure for S.chartarum extract preparation was first optimized related to the age of the culture, culture type, and growth medium, and the antigenic composition of S. chartarum cultured in two different media was then characterized by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting method. Cross-reactivity of S. chartarum antigenic components with 10 other fungal species was identified by the inhibition immunoblotting method. The 10-day-old S. chartarum culture extract cultured in malt extract broth revealed a wider selection of proteins and antigenic components than the 30-day-old culture extract or the culture medium extracts. When cultured in cellulose broth, S. chartarum produced a higher number of proteins and antigenic components than in malt extract broth. The most dominant immunogenic components of S. chartarum cultured in cellulose broth were those of 65, 50, 37, and 27 kDa. The components of 65 and 50 kDa proved to be the most characteristic of this fungus according to the inhibition immunoblotting analyses. Several of the S. chartarum components were identified as glycoproteins. Carbohydrate moieties of the S. chartarum components also possessed an antibody binding activity.

Diffuse pulmonary hemosiderosis after exposure to pesticides. A case report

This report describes the clinical, radiological, microscopical and ligandohistochemical findings in a 17-year-old woman who suffered from an acute onset of pulmonary hemosiderosis after inhalation of pesticides used for the cultivation of strawberries. She complained of headache, dyspnea, rhinitis, weakness and recurrent severe hemoptysis. Chest radiographs revealed bilateral patchy infiltrates, predominantly in the lower parts of both lungs. The consecutive severe anemia was treated by multiple blood transfusions which were repeated every 4-5 days. Open lung biopsies displayed signs of diffuse hemorrhage with hemosiderin-loaded macrophages, some hyaline membranes, focal fibroid deposits with intermingled histiocytes, mild interstitial fibrosis and focal intra-alveolar calcified bodies surrounded by foreign body giant cells. Analysis of endogenous lectins failed to demonstrate expression of binding capacities for maltose, fucose, mannose, lactose and sialic acid, Neither binding capacities for the macrophage-migration-inhibitory factor nor its presence, as analyzed by labeled sarcolectin, could be detected histochemically. The light microscopical findings are consistent with a longer-lasting diffuse pulmonary hemosiderosis; the presence of calcified bodies and foreign body giant cells (including the ligandohistochemical data) argues for a causal role of inhaled substances. The patient's clinical course improved after cyclophosphamide treatment, which restored her ability to work and released her from the need for recurrent blood transfusions.

Mycotoxins, fungus and 'electrohypersensitivity'

'Electrohypersensitivity' is often explained as a psychological syndrome. Our modern environment contains a lot of different substances and some of them are toxic. Mycotoxins are types of toxins that are biologically very active and that affect living organisms. Mycotoxins and fungi capable of producing toxins have been detected in ventilation systems, water damage and in foodstuff. Many of those displaying symptoms caused by electromagnetic fields have fungus infections or have been living in fungus-contaminated environments for long periods. In animal studies mycotoxins have shown the same effects as those seen in the 'electrohypersensitivity' syndrome. Phototoxic reactions are well known in veterinary medicine and in medical science, so the question is whether the 'electrohypersensitivity' syndrome is caused by 'phototoxic' reactions?

Volatile sesquiterpenes from Stachybotrys chartarum: Indicators for trichothecene producing mold species?

Trichodiene, a volatile sesquiterpene which is structurally related to trichothecene mycotoxins, has been identified in the headspace of growing Stachybotrys chartarum by GC/MS. It is possible that volatile sesquiterpene patterns can be used to characterize S. chartarum and related mold isolates as trichothecene producers, thus providing clear criteria for decisions concerning the occupancy and renovation of contaminated buildings.

Cytotoxicity, production of reactive oxygen species and cytokines induced by different strains of Stachybotrys sp. from moldy buildings in RAW264.7 macrophages

The ability of different strains of the fungus Stachybotrys, isolated from mold problem buildings, to induce cytotoxicity and production of important inflammatory mediators, i.e. nitric oxide (NO), reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in RAW264.7 macrophages were studied. Several strains of Stachybotrys sp. stimulated immediate increase in the ROS production and in 24-h exposure caused TNF-α and IL-6 release from these cells. However, none of the strains of Stachybotrys sp. was able to induce the expression of inducible nitric oxide synthase (iNOS) and subsequent production of NO in RAW264.7 cells. Moreover, there were significant differences in their ability to induce cytotoxicity in the macrophages. These results suggest that, in addition to direct cytotoxic effects of most Stachybotrys sp., some strains of Stachybotrys sp. stimulate production of inflammatory mediators, TNF-α and IL-6 which were associated with low cytotoxicity in RAW264.7 macrophages.

Study of toxin production by isolates of Stachybotrys chartarum and Memnoniella echinata isolated during a study of pulmonary hemosiderosis in infants

A cluster of cases of pulmonary hemosiderosis among infants was reported in Cleveland, Ohio, during 1993 and 1994. These unusual cases appeared only in infants ranging in age from 1 to 8 months and were characterized by pulmonary hemorrhage, which caused the babies to cough up blood. A case-control study identified major home water damage (from plumbing leaks, roof leaks, or flooding) as a risk factor for development of pulmonary hemorrhage in these infants. Because of an interest in the possibility that trichothecene mycotoxins might be involved in this illness, a number of isolates of Stachybotrys chartarum were grown in the laboratory on rice, and extracts were prepared and analyzed both for cytotoxicity and for specific toxins. Two isolates of Memnoniella echinata, a fungus closely related to S. chartarum, were also included in these studies. S. chartarum isolates collected from the homes were shown to produce a number of highly toxic compounds, and the profiles of toxic compounds from M. echinata were similar; the most notable difference was the fact that the principal metabolites produced by M. echinata were griseofulvins.