Ex vivo effects of bisphenol A or zearalenone on the prepubertal rat testis.

Bisphenol A (BPA) and zearalenone (ZEA) are two widespread xenoestrogens involved in male reproductive disorders. Few studies investigated the effects of these compounds on the prepubertal testis, which is highly sensitive to endocrine disruptors such as xenoestrogens. An ex vivo approach was performed to evaluate the effects of BPA or ZEA (10-11, 10-9, 10-6 M) on the testes of 20 and 25 dpp rats. To investigate the involvement of classical nuclear ER-mediated estrogen signaling in these effects, pre-incubation with an antagonist (ICI 182.780 10-6 M) was performed. BPA and ZEA have similar effects on spermatogenesis- and steroidogenesis-related endpoints in the immature testis, but our study highlights different age-dependent patterns of sensitivity to each compound during the prepubertal period. Moreover, our results indicate that the effects of BPA are likely to be induced by nuclear ER, whereas those of ZEA appear to involve other mechanisms.

Monitoring of sterigmatocystin biosynthesis using RT-qPCR in airborne Aspergillus species of the series Versicolores.

Aspergilli series Versicolores have been shown to be explanatory variables for different symptoms like coughing and dizziness experienced by residents of mold-damaged homes. Among these species, eight are particularly recurrent in bioaerosols: Aspergillus amoenus, A. creber, A. fructus, A. jensenii, A. protuberus, A. puulaauensis, A. sydowii and A. tabacinus. In order to monitor the biosynthesis of sterigmatocystin (a mycotoxin associated with a risk of cancer development) and the development of these molds, we developed an RT-qPCR tool by targeting the aflR and rho1 genes. A total of 30 fungal isolates representing these eight species were included. For each of them, sterigmatocystin was quantified by UPLC-HRMS and (1 â†’ 3)-ß-D-glucan by visible spectrophotometry using Endosafe®-PTS™-Glucan Cartridges. After validation of our method by RT-qPCR, the direct assay was compared to the amount of aflR and rho1 cDNA. The sterigmatocystin and aflR assays showed a significant correlation between these two approaches (p < 0.0001), demonstrated for the first time the production of sterigmatocystin by A. tabacinus and suggested the ability of A. sydowii to synthesize sterigmatocystin. Assays conducted on (1 â†’ 3)-ß-D-glucan and rho1 did not show a correlation, supporting the multiplicity of functions performed in fungal cells by the RHO1 GTPase. The proposed tool could allow monitoring of sterigmatocystin biosynthesis by Aspergillus of the series Versicolores under different culture and climatic conditions.

Deoxynivalenol enhances estrogen receptor alpha-induced signaling by ligand-independent transactivation.

Deoxynivalenol (DON), which is one of the prevalent mycotoxins in food and feeds, exerts adverse effects on animal and human health. These effects are mainly associated with its ribotoxic properties, although few studies suggest the involvement of other mechanisms of action. To assess the ability of DON to disrupt estrogen signaling, we conducted an in vitro study using MCF-7 and MDA-MB-231 cells. After 72h, DON reduced cell viability in both cell lines, thus highlighting its well-known cytotoxic effect. However, after 6h, DON increased the expression of estrogen-responsive genes, hence demonstrating the stimulation of estrogen signaling by this mycotoxin after a short-term exposure. This effect was partially reversed by siRNA-mediated silencing of ERα expression and by 4-hydroxytamoxifen (ERα antagonist), but neither by G36 (GPER antagonist) nor by the siRNA-mediated silencing of PPARγ2 expression. Moreover, DON exposure induced an increase in the level of ERα phosphorylation at serine 167. Furthermore, when combined with zearalenone (a naturally co-occurring mycotoxin recognized as an endocrine disruptor), DON increased the expression of estrogen-responsive genes to a greater extent than each individual compound taken separately. Taken together, our results suggest, for the first time, that DON can disrupt estrogen signaling through the ligand-independent activation of ERα.

A novel qPCR based-method for detection and quantification of three recurrent species of Penicillium isolated from bioaerosols in mold-damaged homes.

Fungal contamination of indoor environments can cause respiratory diseases and induce damages to building materials. Among the fungal species found in mold-damaged homes, Penicillium brevicompactum, P. chrysogenum and P. crustosum can be considered as recurrent strains. In this study, we therefore propose a rapid and novel qPCR-based method in order to allow the monitoring of these three fungal species. The method developed allows the quantification of the target DNA of these three Penicillium species with a limit of quantification of 0.01 ng/µL without significant difference with spectrophotometry quantification assay for DNA concentrations between 5 and 100 ng/µL. This technique also enables the rapid detection of these three species in complex mixtures of DNA extracted from 15 bioaerosols collected in mold-damaged homes and previously cultured on agar plate. This new sensitive and specific qPCR technique can thus be easily integrated into bioaerosol studies.

Toxigenic fungi and mycotoxins in mature corn silage.

To investigate the exposure of livestock and farm workers to mycotoxins during the last months of silage use, the mycoflora and the mycotoxins in a mature silage (11-months-old) were studied. A multimycotoxin method was developed to evaluate the toxigenic in vitro ability of fungal strains. The screening of potentially toxigenic fungi isolated from the mature silage showed that six Fusaria (Fusarium culmorum, Fusarium equiseti, Fusarium graminearum, Fusarium oxysporum, Fusarium solani and Fusarium verticillioides) and one Aspergillus (Aspergillus fumigatus) were able to produce mycotoxins on nutrient agar. Seven major mycotoxins (aflatoxin B(1), citrinin, deoxynivalenol, fumonisin B(1), gliotoxin, ochratoxin A and zearalenone) were also searched in the corn silage by high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS). Among the three mycotoxins (citrinin, gliotoxin and deoxynivalenol) detected in the silage, gliotoxin, a strongly immunosuppressive mycotoxin, occurred in the mature silage at level up to 877 ppb, which was associated with the presence of A. fumigatus in the silage.

Poisoning by Cnestis ferruginea in Casamance (Senegal): an etiological approach.

Since several years, in the area of Kabrousse in Casamance (Senegal), a neurotoxic syndrome has caused more than 50 human deaths. Field studies showed that epidemic could be due to consumption of leave decoction of Cnestis ferruginea, a tropical plant belonging to the Connaraceae family. An ethnobotanical study has been conducted in order to investigate the traditional uses of C. ferruginea, and describe the circumstances and the symptoms of this plant poisoning. As a first experimental approach, the leave decoction was tested for its ability to induce cytotoxic effects using the XTT method. A phytochemical approach revealed the presence of methionine sulfoximine (MSX), a neurotoxic amino acid, in the plant extract by gas chromatography-mass spectrometry (GC-MS). The description of this poisoning, the cytotoxic activity of the decoction and the occurence of MSX in leaves of C. ferruginea constituted the first etiological data on this poisoning.

Enhanced degradation of fluorene in soil slurry by Absidia cylindrospora and maltosyl-cyclodextrin.

This study investigates the fungal biodegradation of fluorene, a polycyclic aromatic hydrocarbon, in liquid medium and soil slurry. Fungal strains and cyclodextrins were used in order to degrade fluorene and optimize fluorene bioavailability and degradation in soil slurries. After a procedure of selection in solid and liquid media, maltosyl-cyclodextrin, a branched cyclodextrin was chosen. 47 fungal strains isolated from a contaminated site were tested for biodegradation. Results showed the greater efficiency of "adapted" fungi isolated from contaminated soil vs reference strains belonging to the collection of the laboratory. These assays allowed us to select the most efficient strain, Absidia cylindrospora, which was used in a bioaugmentation process. Bioaugmentation tests were performed in an artificially contaminated non-sterile soil. In the presence of A. cylindrospora, more than 90% of the fluorene was degraded within 288 h, while 576 h were necessary in the absence of fungal bioremediation. It also appeared that biodegradation was enhanced by amendment with previously selected maltosyl-cyclodextrin. The results of this study indicate that A. cylindrospora and maltosyl-cyclodextrin could be used successfully in fluorene bioremediation systems.

Influence of surfactants on solubilization and fungal degradation of fluorene.

Eighteen fungal strains were tested in toxicity assays with surfactants in order to select surfactants and strains tolerant to surfactants for degradation assays. Two nonionic surfactants were used, an alkylphenol ethoxylate, Triton X-100, a sorbitan ester, Tween 80 and an anionic surfactant, sodium dodecyl sulfate. Solubilization and biodegradation tests were conducted in liquid medium batch; fluorene was quantified by HPLC. Results showed the enhancement of fluorene solubilization by the three surfactants, good tolerance of nonionic surfactants by the fungal strains and the enhancement of the biodegradation of fluorene by Doratomyces stemonitis (46-62%) and Penicillium chrysogenum (28-61%) in the presence of Tween 80 (0.324 mM) after 2 days.

[Cortinarius poisoning. Analysis of cases in the literature]. / Intoxications par les cortinaires. Analyse des cas de la littérature.

UNLABELLED: Cortinarius spp. poisoning is characterized by a delayed acute renal failure (ARF). The main features of this severe poisoning are still poorly known and often overlooked. The aim of this review of the literature was a better description of Cortinarius spp. poisoning. METHODS: The main medical databases were searched and analysed. RESULTS: 245 cases were collected and 90 cases could be analysed in details. Gastrointestinal disorders appeared a few days after the ingestion of the mushrooms (median: three days). The renal phase is delayed (median: 8.5 days). Hepatic failure and muscular lesions are highly questionable. Treatment is supportive in half of the cases, ARF progressed towards chronic renal failure, which progressed in 70% of the cases towards terminal renal failure. CONCLUSION: Cortinarius spp. poisoning is severe. Ingestion of Cortinarius species must be systematically suspected whenever tubulo-interstitial nephritis is diagnosed.

Main features of Cortinarius spp. poisoning: a literature review.

INTRODUCTION: Cortinarius spp. poisoning is characterized by a delayed acute renal failure. The main features of this severe poisoning are still poorly known and often overlooked. The aim of this literature review is a better description of Cortinarius spp. poisoning. MATERIALS AND METHODS: The main medical databases were searched: Abstracts of Mycology, Current Contents, Medline, Pascal, Micromedex Poisindex, Toxicology abstracts, Toxline. All case reports that included a description of the clinical features of Cortinarius spp. poisoning were studied. RESULTS: 245 cases were collected and 90 cases could be analyzed in details. Gastrointestinal disorders are the main symptoms of the prerenal phase of the poisoning. They appear a few days after the ingestion of the mushrooms (median 3 days). The renal phase is delayed (median 8.5 days). Moderate and transient hepatic abnormalities have been reported. A severe hepatic failure can be ruled out. Muscular lesions are highly questionable. Treatment is supportive. No specific treatment can be recommended. Acute renal failure progressed towards chronic renal failure in half of the cases; intermittent hemodialysis or kidney transplantations were necessary in 70% of those cases. CONCLUSION: Cortinarius spp. poisoning is severe. Ingestion of Cortinarius species must be systematically suspected whenever tubulo-interstitial nephritis is diagnosed, especially as mushrooms may have been ingested 1-2 weeks before.

[Effect of cyclodextrins on fungal degradation of fluorene]. / Effet des cyclodextrines sur la dégradation fongique du fluorène.

The purpose of this study was to improve the bioavailability of fluorene (PAH) by the use of complexing agents, cyclodextrins. The biodegradation tests were performed in liquid medium batches; fluorene was quantified by HPLC. Experimental results showed the enhancement of fluorene degradation by Penicillium italicum and Phanerochaete chrysosporium in the presence of branched cyclodextrins.

Fungal degradation of fluorene.

A selection of 30 strains of micromycetes known as good degraders of polychlorinated aromatic compounds, mostly isolated from soil and belonging to various taxonomic groups, have been investigated to degrade fluorene. Toxicity assays, first evaluated on solid media, have shown high growth inhibition at concentrations above 0.001 g l-1 only towards 23% of strains. Degradation of fluorene (0.005 g l-1) was then investigated in liquid synthetic medium for 2 days and evaluated by HPLC. Among the 30 strains tested, 12 could be considered as best degraders because of a rate of degradation at 60% or over. 3 strains of Cunninghamella genus were very efficient (mean of degradation: 96%) but different strains from Ascomycetes. Basidiomycetes and Deuteromycetes were also efficient 11 strains are not yet reported in the literature: Aspergillus terreus, Bjerkandera adusta, Ceriporiopsis subvermispora, Colletotrichum dematium, Cryphonectria parasitica, Cunninghamella blakesleeana, C. echinulata, Drechslera spicifera, Embellisia annulata, Rhizoctonia solani and Sporormiella australis. A metabolic approach with standard compounds (9-fluorenol and 9-fluorenone) indicated the presence of these monooxygenated derivatives for most of the strains.