Search results for "toxin"
showing 10 items of 1434 documents
Mycotoxin mixtures in food and feed: a holistic, innovative, flexible modelling approach for risk assessment MYCHIF
2019
Mycotoxin contamination can occur in many agricultural products both destined to food and feed. Mycotoxins are produced as the result of fungal metabolism and plant-pathogen interaction. Therefore, many structurally-related congeners, defined as modified mycotoxins are generated by plant &/or fungi metabolism, or food processing, and coexist with their native forms. Studies investigating the co-occurrence of multiple-mycotoxins reported 75%100% of samples containing more than one mycotoxin, referring to native compounds and 100% reported multiple modified forms. A major challenge in a risk assessment is to depict the biosynthesis of mycotoxin mixtures and their realistic occurrence. Over th…
Evaluación del riesgo de la presencia de micotoxinas en piensos comercializados en España mediante métodos cromatográficos multidetección y alta reso…
2016
Las micotoxinas son metabolitos secundarios producidos por determinados hongos, y son contaminantes frecuentes de alimentos y piensos. Producen enfermedades, denominadas micotoxicosis, que pueden ser tanto agudas como crónicas en personas y animales. A nivel de salud humana afectan fundamentalmente al hígado, los riñones y el sistema inmune, mientras que sus efectos en salud animal son más variados, dependiendo de otros factores como la especie, la edad, etc. La Agencia Internacional de Investigación sobre el Cáncer (“International Agency for Research on Cancer”, IARC) ha clasificado las aflatoxinas como uno de los compuestos naturales con mayor potencial cancerígeno y teratógeno que existe…
Adaptogens in chemobrain (Part III): Antitoxic effects of plant extracts towards cancer chemotherapy-induced toxicity - transcriptome-wide microarray…
2019
Abstract Background Toxicity of chemotherapeutics is a serious problem in cancer therapy. Adaptogens are known to increase adaptability and survival organisms. Aim The aim of this study was to assess the effects of selected adaptogenic herbal extracts on FEC (fixed combination of 5-fluorouracil, epirubicin and cyclophosphamide) induced changes in transcriptome-wide microarray profiles of neuroglia cells. Another task of the study was to identify those genes, which are associated with FEC-induced hepato-, cardio– and nephrotoxicity to predict potential effects of andrographolide (AND), Andrographis herb, Eleutherococcus roots genuine extracts (ES), their fixed combination (AE) and the combin…
Factors Determining Sensitivity and Resistance of Tumor Cells to Arsenic Trioxide
2012
Previously, arsenic trioxide showed impressive regression rates of acute promyelocytic leukemia. Here, we investigated molecular determinants of sensitivity and resistance of cell lines of different tumor types towards arsenic trioxide. Arsenic trioxide was the most cytotoxic compound among 8 arsenicals investigated in the NCI cell line panel. We correlated transcriptome-wide microarray-based mRNA expression to the IC(50) values for arsenic trioxide by bioinformatic approaches (COMPARE and hierarchical cluster analyses, Ingenuity signaling pathway analysis). Among the identified pathways were signaling routes for p53, integrin-linked kinase, and actin cytoskeleton. Genes from these pathways…
Determination of mycotoxins produced by Fusarium isolates from banana fruits by capillary gas chromatography and high-performance liquid chromatograp…
1997
A method of analysis for trichothecenes (nivalenol, deoxynivalenol, 3- and 15-acetyldeoxynivalenol, diacetoxyscirpenol, neosolaniol, T-2 tetraol, T-2 and HT-2 toxins), zearalenone and zearalenols, and another method for determination of fumonisin B1 are described and applied to cultures of Fusarium isolated from bananas. Both methods were adapted from different techniques of extraction, clean-up and determination of these mycotoxins. The first method involves extraction with methanol-1% aqueous sodium chloride, clean-up of extracts by partition with hexane and dichloromethane, additional solid reversed-phase clean-up and analysis of two eluates by both high-performance liquid chromatography…
Aflatoxins and ochratoxin A in stored barley grain in Spain and impact of PCR-based strategies to assess the occurrence of aflatoxigenic and ochratox…
2011
Contamination of barley by moulds and mycotoxins results in quality and nutritional losses and represents a significant hazard to the food chain. The presence of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) and ochratoxin A (OTA) in stored barley in Spain has been studied. Species-specific PCR assays were used for detection of Aspergillus flavus, A. parasiticus, A. ochraceus, A. steynii, A. westerdijkiae, A. carbonarius and A. niger aggregate in mycotoxin-positive barley samples at different incubation times (0, 1 and 2 days). Classical enumeration techniques (CFU/g) in different culture media for evaluation of Aspergillus in sections Flavi, Circumdati and Nigri were also used. O…
The Independent Biological Activity of Bacillus thuringiensis Cry23Aa Protein Against Cylas puncticollis
2020
The Cry23Aa/Cry37Aa proteins from Bacillus thuringiensis (Bt) have been described toxic to Cylas puncticollis larvae. In general, it is believed that Cry23Aa and Cry37Aa act jointly to exert the insecticidal activity, while there is no evidence of their toxicity individually. Therefore, in the present study, the contribution of each protein in the insecticidal activity toward C. puncticollis larvae has been assessed. The results showed that both proteins were toxic for C. puncticollis larvae when tested individually. Contrary to what was claimed previously, our results suggest that the presence of both proteins is not necessary to exert toxicity against C. puncticollis larvae. Also, the bin…
Characterization ofBacillus thuringiensisisolated from infections in burn wounds
1997
Four strains of Bacillus thuringiensis were isolated from infections in burn wounds and from water used in the treatment of burn wounds. The strains produced large parasporal inclusion bodies composed of 141, 83, and 81 kDa protoxins. The four strains were tested for insecticidal activity against larvae of Pieris brassicae and Aedes aegypti but showed no activity; Vero cell assays for the production of enterotoxins were also negative. Attempts to classify the strains according to flagellar H-serotype showed them all to be non-flagellated. Apart from two occupational health accidents that occurred during the handling of highly concentrated B. thuringiensis fluids, this is the first report of…
In vivo effects of intravascularly applied Escherichia coli hemolysin: dissociation between induction of granulocytopenia and lethality in monkeys.
1993
The effects of intravascular application of endotoxin-depleted Escherichia coli hemolysin (HlyA) was studied in rabbits and monkeys. In rabbits, bolus application of HlyA calculated to effect final blood levels of approximately 2-3 HU/ml (200-300 ng/ml) caused an acute fall of polymorphonuclear blood leukocytes to less than 20% of starting levels within 5 min. Additionally, platelet counts dropped to approximately 30% of starting levels, whereas lymphocyte counts varied considerably and seldom fell to less than 50%. Nine out ten animals that received 2-4 HU/ml toxin died within 90 min post application. These animals presented with signs of acute respiratory failure and post mortem inspectio…
Specific DNA probes to detect Escherichia coli strains producing cytotoxic necrotising factor type 1 or type 2
1994
Cytotoxic necrotising factors type 1 (CNF1) and type 2 (CNF2) are produced by many Escherichia coli strains isolated from man and animals with intestinal or extra-intestinal colibacillosis. In most laboratories, CNF-producing strains are detected by a cell cytotoxicity assay and confirmed with a neutralisation assay or a mouse footpad assay. In this study, we sought to determine whether DNA probes could detect clinical isolates of E. coli producing CNF2 or CNF1, or both, without the need for cell cultures or animal assays. Two internal fragments of the gene encoding CNF2 were used as DNA probes: a 875-bp XhoI-PstI DNA fragment and an adjacent 335-bp PstI-ClaI fragment. A positive response w…