Search results for "toxins"
showing 10 items of 799 documents
Determination of Fungi and Multi-Class Mycotoxins in Camelia sinensis and Herbal Teas and Dietary Exposure Assessment
2020
In this paper, a study of fungal and multi-mycotoxin contamination in 140 Camellia sinensis and 26 herbal teas marketed in Latvia is discussed. The analysis was performed using two-dimensional liquid chromatography with time-of-flight mass spectrometry (2D-LC-TOF-MS) and MALDI-TOF-MS. In total, 87% of the tea samples tested positive for 32 fungal species belonging to 17 genera, with the total enumeration of moulds ranging between 1.00 ×
Potential of the Bacillus thuringiensis Toxin Reservoir for the Control of Lobesia botrana (Lepidoptera: Tortricidae), a Major Pest of Grape Plants▿
2006
ABSTRACT The potential of Bacillus thuringiensis Cry proteins to control the grape pest Lobesia botrana was explored by testing first-instar larvae with Cry proteins belonging to the Cry1, Cry2, and Cry9 groups selected for their documented activities against Lepidoptera. Cry9Ca, a toxin from B. thuringiensis , was the protein most toxic to L. botrana larvae, followed in decreasing order by Cry2Ab, Cry1Ab, Cry2Aa, and Cry1Ia7, with 50% lethal concentration values of 0.09, 0.1, 1.4, 3.2, and 8.5 μg/ml of diet, respectively. In contrast, Cry1Fa and Cry1JA were not active at the assayed concentration (100 μg/ml). In vitro binding and competition experiments showed that none of the toxins teste…
Multi-mycotoxin determination in barley and derived products from Tunisia and estimation of their dietary intake.
2017
A study on raw barley and derived products (barley soup and beers) was carried out to determine the natural presence of twenty-four mycotoxins by both liquid chromatography and gas chromatography coupled to tandem mass spectrometry (MS/MS). The developed multi-mycotoxin procedure was based on both SLE and QuEChERS extraction steps. 66% of analyzed samples presented mycotoxin contamination and only one sample, which was soup of barley (6 ng/g), exceeded the maximum level (ML) established by EU for OTA (5 ng/g). Raw barley was the most contaminated matrix (62%), which concentrations ranged from 1.70 to 287.13 ng/g) and type of detected mycotoxins (DON, 15AcDON, NEO, NIV, HT2, FB1, OTA, ENA, E…
Evaluación del riesgo toxicológico por exposición a micotoxinas y extracto de calabaza mediante técnicas ómicas y moleculares
2022
Beauvericina (BEA) y eniatina B (ENB) son micotoxinas no legisladas de Fusarium que se encuentran habitualmente en los cereales y productos a base de cereales de todo el mundo. El objetivo principal de este trabajo es evaluar algunos de los protocolos existentes para descubrir las variantes de un solo nucleótido (SNVs) en los datos transcriptómicos obtenidos por secuenciación de ARN (RNA-seq) de células Jurkat expuestas individualmente a BEA y ENB a tres niveles de concentración (1,5, 3 y 5 µM). También se comparan los resultados del análisis transcriptómico realizado en trabajos anteriores con los nuevos obtenidos mediante un protocolo diferente. El SNV-protocol 1 no mostró ningún SNV. El …
Analytical study and exposure to Fusarium mycotoxins = Estudio analítico y de exposición a micotoxinas de Fusarium
2015
Las micotoxinas son metabolitos secundarios de determinadas especies fúngicas que se encuentran habitualmente en los alimentos. El Reglamento No. 1881/2006 de la Comisión Europea, parcialmente modificado por posteriores Reglamentos, establece los contenidos máximos de micotoxinas para diferentes productos alimenticios. La introducción de estas normas pone de manifiesto el interés por el conocimiento de valores relativos a la concentración de estos tóxicos para poder evaluar riesgos y adoptar las medidas necesarias para proteger la salud de los consumidores. Los productos agrícolas contaminados, especialmente cereales y sus derivados, son la principal fuente de micotoxinas en la dieta de la …
UDP-glucose deficiency in a mutant cell line protects against glucosyltransferase toxins from Clostridium difficile and Clostridium sordellii.
1996
Abstract We have previously isolated a fibroblast mutant cell with high resistance to the two Rho-modifying glucosyltransferase toxins A and B of Clostridium difficile. We demonstrate here a low level of UDP-glucose in the mutant, which explains its toxin resistance since: (i) to obtain a detectable toxin B-mediated Rho modification in lysates of mutant cells, addition of UDP-glucose was required, and it promoted the Rho modification dose-dependently; (ii) high pressure liquid chromatography analysis of nucleotide extracts of cells indicated that the level of UDP-glucose in the mutant (0.8 nmol/106 cells) was lower than in the wild type (3.7 nmol/106 cells); and (iii) sensitivity to toxin B…
A1. FATTORI INERENTI ALLO SVILUPPO DI FIORITURE DI CIANOBATTERI TOSSICI CON PARTICOLARE RIFERIMENTO A EUTROFIZZAZIONE E CAMBIAMENTI CLIMATICI
2014
I cianobatteri sono diffusi in moltissimi ambienti acquatici, dove possono produrre cianotossine con diversi profili tossicologici. Il presente rapporto riporta le linee guida per la gestione delle fioriture di cianobatteri nelle acque di balneazione, elaborate da un gruppo di esperti. La prima parte sintetizza le attuali conoscenze scientifiche su vari aspetti, fra cui la loro presenza nei laghi italiani, le caratteristiche chimiche e tossicologiche delle varie cianotossine, gli effetti osservati sulla salute dell’uomo e la valutazione del rischio. La seconda parte definisce le linee guida per prevenire effetti dannosi per la salute dei bagnanti e gestire il rischio associato alle fioritur…
A7. SITUAZIONE NAZIONALE: CORPI IDRICI INTERESSATI DA CIANOBATTERI TOSSICI
2014
I cianobatteri sono diffusi in moltissimi ambienti acquatici, dove possono produrre cianotossine con diversi profili tossicologici. Il presente rapporto riporta le linee guida per la gestione delle fioriture di cianobatteri nelle acque di balneazione, elaborate da un gruppo di esperti. La prima parte sintetizza le attuali conoscenze scientifiche su vari aspetti, fra cui la loro presenza nei laghi italiani, le caratteristiche chimiche e tossicologiche delle varie cianotossine, gli effetti osservati sulla salute dell’uomo e la valutazione del rischio. La seconda parte definisce le linee guida per prevenire effetti dannosi per la salute dei bagnanti e gestire il rischio associato alle fioritur…
Staphylococcus aureus alpha toxin mediates polymorphonuclear leukocyte-induced vasocontraction and endothelial dysfunction.
2002
The effect of Staphylococcus aureus alpha toxin (alpha-toxin) on selectin-mediated neutrophil adhesion was investigated in polymorphonuclear leukocyte- (PMN) induced vasocontraction and endothelial dysfunction. Adherence of human PMNs to rat aortic endothelium increased significantly following stimulation of the endothelium with alpha-toxin (0.1, 0.5, and 1 microg/mL). This effect could be significantly attenuated by monoclonal antibodies directed against P-selectin or fucoidin, a carbohydrate known to block selectins. Unstimulated human PMNs (10(6)cells/mL) were added to organ chambers containing rat aortic rings stimulated with alpha-toxin (0.5 microg/mL). PMNs elicited a significant vaso…
Toxicity of several d-endotoxins of Bacillus thuringiensis against Helicoverpa armigera (Lepidoptera: Noctuidae) from Spain
2005
Abstract Toxicity and larval growth inhibition of 11 insecticidal proteins of Bacillus thuringiensis were evaluated against neonate larvae of Helicoverpa armigera, a major pest of important crops in Spain and other countries, by a whole-diet contamination method. The most active toxins were Cry1Ac4 and Cry2Aa1, with LC50 values of 3.5 and 6.3 μg/ml, respectively. At the concentrations tested, Cry1Ac4, Cry2Aa1, Cry9Ca, Cry1Fa1, Cry1Ab3, Cry2Ab2, Cry1Da, and Cry1Ja1, produced a significant growth inhibition, whereas Cry1Aa3, Cry1Ca2, and Cry1Ea had no effect.