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We examined the blastogenic response to phytohaemaglutinin (PHA) in HLA-B8, DR3 positive and negative subjects in the presence or absence of the immunosuppressive Fusarium mycotoxin.  HLA-B8, DR3 haplotype was associated with a depression of the response to mitogen in the absence of the mycotoxin, whereas in the presence of deoxynivalenol we could not detect significant differences among individuals either possessing or lacking this haplotype.

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Fusarium head blight (FHB) of oat in western Canada was determined to be caused by a complex of Fusarium species, the composition and proportions of which varied considerably among years, and between Manitoba and Saskatchewan, the two main oat production regions (provinces) in western Canada. The levels of deoxynivalenol (DON), associated with Fusarium graminearum infection, were considerably higher in oat than in wheat and especially in barley, when levels of DON were compared to those of F. graminearum on seed, suggesting that oat may stimulate production of the mycotoxin by this causal species during the infection process, compared to that in other cereals. Testing of oat cultivars and lines for reaction to FHB indicated that while differences existed, these were relatively small. ‘Naked’ oats, in general, were more resistant. Several of the exotic oat accessions tested appeared to have superior levels of resistance and these are being used as parents in crosses to improve resistance in adapted, high quality oats.

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This study was conducted to investigate the effects of deoxynivalenol (DON) and zearalenone (ZEA) on some biochemical indices of broiler chickens. Twenty-four Ross 308 hybrid broiler chickens of both sexes were fed diets containing maize contaminated with Fusarium mycotoxins. The diets included a control diet (DON 0.60 mg/kg feed; ZEA 0.07 mg/kg feed), an experimental 1 diet (DON 3.4 mg kg −1 feed; ZEA 3.4 mg kg −1 feed), and an experimental 2 diet (DON 8.2 mg kg −1 feed; ZEA 8.3 mg kg −1 feed). Contaminated diets were fed from 14 days of age for 14 days. Blood samples were collected from 4-week-old birds. Chicks fed a diet containing a low level of contaminated maize (experimental 1) had decreased plasma potassium, magnesium, phosphorus, total protein, albumin, triglycerides, free glycerol concentrations and increased cholesterol and calcium levels as well as alkaline phosphatase (ALP) and aspartate aminotransferase (AST) enzyme activities as compared to the control. Feeding a diet contaminated with high levels of mycotoxins (experimental 2) resulted in decreased plasma potassium, magnesium, total protein, albumin, triglycerides, free glycerol concentrations and increased plasma ALP, alanine aminotransferase (ALT) and AST enzyme activities. The effect of mycotoxin-contaminated diets on ALP activity was dose dependent. Chloride concentration was not affected by the diets. It can be concluded that feeding diets contaminated with both levels of Fusarium mycotoxins significantly affected protein, lipid and mineral metabolism as well as AST and ALP enzyme activities in broiler chickens.

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of cultural practices on head blight attacks and the production of mycotoxins by Fusarium in wheat grains. Plant Sci. 166 :1389–1415. Fourbet J.F. Fusarium head blight

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The influence of three milling techniques (MT1: industrial roller-grinder, MT2: grain hammer crasher, and MT3: traditional millstone) and two baking methods (BM1: industrial oven, BM2: traditional ceramic stove heated by wood (log fire oven)) on mycotoxin deoxynivalenol (DON) and nivalenol (NIV) levels in bread were investigated. The DON and NIV concentrations in wheat grain, flour, and bread were analysed using high performance liquid chromatography with UV-detection methods. The 2 500 kg lot of wheat grain containing 1 400–1 900 μg kg −1 deoxynivalenol and 130–200 μg kg −1 nivalenol was divided into sub-lots which were processed to get three types of flour (F1: industrial bread flour, F2: industrial wholegrain flour and F3: traditional wholegrain flour). The concentrations of DON and NIV measured after milling the grain according to MT1 (yielding F1) amounted to 310–370 \g kg −1 and <50–70 μg kg t1 , respectively. After applying MT2 to the grain (yielding F2), the DON and NIV levels were measured to be 1 060–1 400 μg kg −1 and 60–87 μg kg −1 , respectively. Applying MT3 (yielding F3) produced a DON level of 1 100–1 770 μg kg 1 and a NIV level of 80–95 μg kg −1 . Six types of bread were baked from the three types of flour according to BM1 or BM2, and the mycotoxin levels were analysed. The average reduction in DON concentration after baking (70 min at 195–235 °C) was 47.2% for bread baked in the industrial oven and 48.7% for bread baked in the log fire oven. Concentrations of DON in bread prepared by the industrial MT1 were under the permitted limit of 500 μg kg −1 stated in EC (2006) regulation, despite the fact that the bread was baked from grains highly contaminated with mycotoxins. In the bread baked from traditional wholegrain flour, mycotoxin concentrations were higher (850–950 μg kg −1 ).

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Papaver somniferum produces secondary metabolites, which have important roles in their self-defence processes, in plant biochemistry and in allelochemistry. We can see that different stress effects change the quantity of alkaloids. The object of the experiments is, in what manner changes the content of alkaloids of poppy in case of irregular stress effects. Papaver somniferum (cv. 'Kék Duna', Budakalász) plants were grown for 2 months from seeds in quartz-sand (in natural light, temperature: 24-28 °C, in Knop's nutritive solution). In this paper we studied the alkaloid of poppy treated with two kind of stress factors: mycotoxin and drought, respectively. Both the quantity and the spectrum of alkaloids were measured after different separation procedures. Thin layer chromatography (TLC and HPTLC) and high performance liquid chromatography (HPLC) were applied. Content of the level of formaldehyde (HCHO) also increases in plants with different stress effects. Our presupposition is that the formation of methyl groups of poppy alkaloids takes place through HCHO. It gave us an opportunity to examine changing of formaldehyde (HCHO) level in biotic and abiotic stress situation. Formaldehyde in dimedone adduct form can be detected in injured tissues of Papaver somniferum. As a consequence, the stress effects can be detected in poppy plants by two kinds of method. At first we measured content of alkaloids. Drought stress produced a higher level of the alkaloids, but the mycotoxin stress did not show significant results.

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The mycotoxins β-zearalenol (β-ZOL) and deoxynivalenol (DON) produce toxic effects that result in diseases in humans and animals. The molecular mechanisms that control the mycotoxin-mediated effects are far from being completely understood. Various results show that these mycotoxins could inhibit cell proliferation. In the present short communication, the influence of β-ZOL and DON on the abundance and phosphorylation state of kinases that are included in regulation of the initiation of mRNA translation (which is correlated with cell proliferation) was compared in porcine endometrial cells (PEC). Our results indicate that these mycotoxins modulate the expression and phosphorylation of these factors in a different manner. Whereas β-ZOL mainly had an impact on the biological activity of the extracellular signal-regulated protein kinases 1 and 2 (ERK1/2), protein kinase B (Akt), eukaryotic initiation factor 4E (eIF4E) and its repressor 4E binding protein 1 (4E-BP1), DON reduced the abundance of p38 MAPk, Akt and specific 4E-BP1 bands. In summary, these results indicate that β-ZOL influences molecular events that are included in the initiation of mRNA translation in the porcine endometrium but DON does not alter such processes clearly.

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Mycotoxins are natural compounds that may cause various adverse toxicological manifestations in humans and animals. The nature, the severity and scope of their adverse activity are varied and in general, even in small amount they have potent carcinogenic, genotoxic effect and injure the immune system. In order to provide high level of health protection for consumers, the European Union has established strict regulatory limits, whose implementation is enforced.The EC (2001) Commission Regulation sets maximum levels for some mycotoxins in foodstuffs: for aflatoxins, ochratoxin A, patulin, deoxynivalenol, zearalenone, fumonisins, T-2 and HT-2 toxins. Particular product categories are regulated under specific decisions ordaining control of imported consignments at the point of entry. Due to the fact that only aflatoxins are addressed in the specific decisions, they are the mostly detected and notified mycotoxins in the EU Rapid Alert System for Food and Feed (RASFF). The second most frequent group, Ochratoxin A is typically detected during internal EU market controls. Most RASFF notifications concern product categories falling under specific EU decisions, especially the Aflatoxin content of nuts and nut products. Significant amount of aflatoxins can be found also in dried fruits, spices and herbs.The article reviews and analyses the data available in rapid alert system concerning mycotoxins notification, and evaluates the usefulness of this information for risk assessment. The value of RASFF system is unquestionable and it fulfils its intended function included in its name. The system is a significant source of valuable information, but for risk assessment purposes, other additional information is needed. It could be used most effectively for risk assessment, if it was to provide data on the ratio of all/tested/positive lots and if the authorities provided not only the positive results, but also the exact mycotoxins level of every analysed sample.

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Acta Veterinaria Hungarica
Authors: Viera Revajová, Mikuláš Levkut, Mária Levkutová, Radka Bořutová, Ľubomíra Grešaková, Božena Košiková, and Ľubomír Leng

The objective of the study was to investigate the effects of lignin supplementation of a diet contaminated with the Fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEA) on peripheral blood leukocytes and duodenal immunocompetent cells in broiler chickens. From day 1 after hatching, all chickens were fed an identical control diet for two weeks. Then chickens of Group 1 continued to be fed the control diet, whereas Group 2 was fed the same diet supplemented with lignin at 0.5% level. Simultaneously, Group 3 started to receive a diet contaminated with DON (2.95 mg kg−1) and ZEA (1.59 mg kg−1), while Group 4 received an identical contaminated diet supplemented with 0.5% lignin for further two weeks. Samples of blood and duodenal tissue were collected from 6 birds of each group at 4 weeks of age. Neither counts of white blood cells nor phagocytic function in the peripheral blood were significantly affected in the mycotoxin- and/or lignin-treated birds. As compared to the control, increased numbers of IgM-bearing cells were found in the peripheral blood in Group 3 fed the contaminated diet (P < 0.05) and in Group 4 given the contaminated diet supplemented with lignin (P < 0.01). While the contaminated diet led to reduced numbers of duodenal CD4+ cells, in Group 2 treated only with lignin the number of duodenal CD4+ cells was increased. Lignin enrichment of the contaminated diet did not eliminate the mycotoxin-induced reduction in the number of duodenal CD4+ cells. The results suggest that dietary supplementation of lignin as an indigestible compound to poultry feed may increase the density of some intestinal immunocompetent cells without exerting effects on that in the peripheral blood. However, when added to a diet contaminated with Fusarium mycotoxins, lignin did not prevent the mycotoxin-induced changes in the numbers of blood and intestinal immunocompetent cells.

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The mycotoxin T-2 has many harmful effects on mammalian cells and reproductive functions. In the present study, the in vitro effect of T-2 toxin on mouse blastocysts was examined. Embryos were cultured in media supplemented with 0.5, 0.75 and 1 ng/ml T-2. Different exposure times were applied [96 h (treatment I) or 24 h following 72 h in toxin-free media (treatment II)]. Blastomere number, nuclear chromatin status and blastocoel formation were investigated in blastocysts. Our data show that the effect of T-2 toxin may vary depending on the stage of the embryo at the start of exposure. At 96 h of exposure, the blastocysts had blastomeres with normal chromatin quality but their developmental potential was decreased. After 24 h of exposure applied following a 72-h culture, blastomeres had a higher level of chromatin damage, although their developmental potential was the same as in the control embryos. In both cases, decreased mitotic rate was found, which resulted in decreased blastomere number even at low toxin concentration.

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