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1.
Biomedical and Environmental Sciences ; (12): 351-362, 2017.
Article Dans Anglais | WPRIM | ID: wpr-311405

Résumé

<p><b>OBJECTIVE</b>To investigate chondrocyte apoptosis and the expression of biochemical markers associated with apoptosis in Kashin-Beck disease (KBD) and in an established T-2 toxin- and selenium (Se) deficiency-induced rat model.</p><p><b>METHODS</b>Cartilages were collected from the hand phalanges of five patients with KBD and five healthy children. Sprague-Dawley rats were administered a selenium-deficient diet for 4 weeks prior to T-2 toxin exposure. The apoptotic chondrocytes were observed by terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Caspase-3, p53, Bcl-2, and Bax proteins in the cartilages were visualized by immunohistochemistry, their protein levels were determined by Western blotting, and mRNA levels were determined by real-time reverse transcription polymerase chain reaction.</p><p><b>RESULTS</b>Increased chondrocyte apoptosis was observed in the cartilages of children with KBD. Increased apoptotic and caspase-3-stained cells were observed in the cartilages of rats fed with normal and Se-deficient diets plus T-2 toxin exposure compared to those in rats fed with normal and Se-deficient diets. Caspase-3, p53, and Bax proteins and mRNA levels were higher, whereas Bcl-2 levels were lower in rats fed with normal or Se-deficiency diets supplemented with T-2 toxin than the corresponding levels in rats fed with normal diet.</p><p><b>CONCLUSION</b>T-2 toxin under a selenium-deficient nutritional status induces chondrocyte death, which emphasizes the role of chondrocyte apoptosis in cartilage damage and progression of KBD.</p>


Sujets)
Adolescent , Animaux , Enfant , Femelle , Humains , Mâle , Rats , Apoptose , Marqueurs biologiques , Cartilage articulaire , Chondrocytes , Physiologie , Maladie de Kashin-Beck , Matrilines , Génétique , Métabolisme , Modèles animaux , Répartition aléatoire , Rat Sprague-Dawley , Sélénium , Toxine T-2 , Pharmacologie
2.
Biomedical and Environmental Sciences ; (12): 851-854, 2017.
Article Dans Anglais | WPRIM | ID: wpr-311338

Résumé

Twelve healthy rats were divided into the T-2 toxin group receiving gavage of 1 mg/kg T-2 toxin and the control group receiving gavage of normal saline. Total relative concentrations of T-2 toxin and HT-2 toxin in the skeletal system (thighbone, knee joints, and costal cartilage) were significantly higher than those in the heart, liver, and kidneys (P < 0.05). The relative concentrations of T-2 toxin and HT-2 toxin in the skeletal system (thighbone and costal cartilage) were also significantly higher than those in the heart, liver, and kidneys. The rats administered T-2 toxin showed rapid metabolism compared with that in rats administered HT-2 toxin, and the metabolic conversion rates in the different tissues were 68.20%-90.70%.


Sujets)
Animaux , Rats , Os et tissu osseux , Chimie , Métabolisme , Rat Sprague-Dawley , Toxine T-2 , Pharmacocinétique , Toxicité , Distribution tissulaire , Tests de toxicité aigüe
3.
Arq. bras. med. vet. zootec ; 68(3): 709-715, tab
Article Dans Anglais | LILACS, VETINDEX | ID: lil-785704

Résumé

A trial was conducted to evaluate a feed additive containing epoxidase activity from a bacterium (Mycofix-S) as a potential protection against the adverse effects of 2.5 ppm dietary T-2 toxin in male growing broiler chickens. A total of 144 one-day-old Ross 308 male chicks were individually wing-banded and allotted into each of the four experimental groups. Group 1: negative control, no T-2 toxin or additive; group 2: Mycofix-S, 2.5 g/kg; group 3: positive control, 2.5 ppm T-2 toxin; group 4: 2.5 ppm T-2 toxin + 2.5 g/kg Mycofix-S. Feed and water were provided ad libitum for 28 days (days 1 to 28 of age). Each experimental treatment was replicated 6 times, with 6 birds per replicate pen. Response variables included performance parameters, serum activity of alkaline phosphatase (ALP) and amylase, relative weight of selected organs and histology of the upper digestive system. T-2 toxin at 2.5 ppm significantly (P = 0.016) decreased the 28-day body weight gain and cumulative feed intake without affecting feed conversion. The feed additive counteracted these adverse effects. Serum enzyme activities were not significantly (P>0.05) affected for the four experimental groups but when data from the groups receiving T-2 toxin was pooled and compared against the pooled data from groups without the toxin a significant decrease in amylase activity was observed in chickens receiving T-2 toxin. The histological examination of the upper digestive system revealed lesions in mouth, esophagus, proventriculus, gizzard and duodenum in the chickens fed T-2 toxin without the additive. Chickens fed T-2 toxin plus the additive showed lesions in the same tissues except in the duodenum. The results of the present study show that the addition of 2.5 g/kg of the feed additive tested protects against adverse effects on performance and also the integrity of the duodenal mucosa.(AU)


Foi realizado um experimento com o objetivo de avaliar um aditivo alimentar contendo atividade de epoxidase de uma bactéria (Mycofix-S) como proteção potencial contra os efeitos adversos de uma dieta com 2,5ppm de toxina T-2 em frangos de corte machos. Um total de 144 pintos machos Ross 308 de um dia de idade foram marcados na asa individualmente e alocados em um de quatro grupos experimentais: grupo 1: controle negativo, sem toxina T-2 ou aditivo; grupo 2: 2,5g/kg de Mycofix-S; grupo 3: controle positivo, 2,5ppm de toxina T-2; grupo 4: 2,5ppm de toxina T-2 + 2,5g/kg de Mycofix-S. Alimento e água foram fornecidos ad libitum por 28 dias (dias um a 28 de idade). Cada tratamento experimental foi replicado seis vezes, com seis pintos por gaiola de replicação. As variáveis de resposta incluíram parâmetros de desempenho, atividade sérica de fosfatase alcalina (ALP) e amilase, peso relativo de órgãos selecionados e histologia do sistema digestivo superior. A toxina T-2 a 2,5ppm diminuiu significativamente (P = 0.016) o ganho de peso corporal aos 28 dias e o consumo de alimento acumulado, sem afetar a conversão alimentar. O aditivo diminuiu os efeitos adversos. As atividades séricas das enzimas não foram afetadas significativamente (P>0.05) nos quatro grupos experimentais, porém, quando os dados dos grupos que receberam a toxina T-2 foram combinados e comparados com o pool de dados dos grupos sem toxina, foi observado um decréscimo significativo da atividade de amilase nos frangos que receberam a toxina T-2. O exame histológico do sistema digestivo superior revelou lesões em boca, esôfago, pró-ventrículo, moela e duodeno nos frangos alimentados com toxina T-2 sem aditivo. Frangos alimentados com toxina T-2 mais aditivo mostraram lesões nos mesmos tecidos, exceto no duodeno. Os resultados do presente estudo mostram que a adição de 2,5g/kg do aditivo alimentar testado protege contra os efeitos adversos sobre o desempenho e a integridade da mucosa duodenal.(AU)


Sujets)
Animaux , Amylases , Poulets , Système digestif , Additifs alimentaires , Trichothécènes , Régime alimentaire/médecine vétérinaire , Duodénum , Mycotoxines , Toxine T-2
4.
Journal of Southern Medical University ; (12): 225-229, 2013.
Article Dans Chinois | WPRIM | ID: wpr-322076

Résumé

<p><b>OBJECTIVE</b>To observe the effect of nano-Se-chondroitin sulfate on the growth and apoptosis of chondrocytes from patients with Kashin-Beck disease (KBD) exposed to T-2 toxin in vitro.</p><p><b>METHODS</b>Samples of the articular cartilage were obtained from 6 patients with grade II/III KBD diagnosed in line with the National Clinical Diagnostic Criteria of KBD (WS/T 207-2010) for chondrocyte separation and culture in vitro. The separated chondrocytes were treated with synthesized nano-Se-chondroitin sulfate particles and T-2 toxin, alone or in combination, and the cell growth and apoptosis were observed using MTT assay, HE staining and flow cytometry.</p><p><b>RESULTS</b>The synthesized nano-Se-chondroitin sulfate, with a selenium entrapment ratio of 10.1%, spontaneously formed nanoparticles in distilled water with sizes ranging from 30 to 200 nm. Fourier-transform infrared spectroscopy suggested a possible covalent bond that bound Nano-Se and chondroitin sulfate. Within the concentration range of 50-200 ng/ml, nano-Se-chondroitin sulfate significantly inhibited T-2 toxin-induced apoptosis of the cultured chondrocytes and reduced the early apoptosis rate to (8.64∓1.57)% (P<0.05).</p><p><b>CONCLUSION</b>Nano-Se-chondroitin sulfate can inhibit T-2 toxin-induced apoptosis of cultured chondrocytes from KBD patients in vitro, and serves as a promising candidate therapeutic agent for KBD.</p>


Sujets)
Humains , Adulte d'âge moyen , Apoptose , Cellules cultivées , Chondrocytes , Anatomopathologie , Chondroïtines sulfate , Pharmacologie , Maladie de Kashin-Beck , Anatomopathologie , Nanostructures , Toxine T-2 , Toxicité
5.
Iranian Journal of Public Health. 2009; 38 (4): 111-116
Dans Anglais | IMEMR | ID: emr-93588

Résumé

Rice is one of the crops, which are prone to be contaminated with toxigenic fungi and their mycotoxins. This study aimed to investigate the natural occurrence of T-2 toxin in domestic and imported rice in Iran. In a cross-sectional descriptive study in winter 2007, 140 samples of imported rice [125 samples of Thai and 25 samples of Pakistani rice] and 60 samples of Iranian rice were collected from warehouses of canteens of governmental offices in Tehran. After grinding and methanol extraction of the rice samples, the amount of T-2 toxin was measured using a sandwich ELISA. INSTATA statistical software was used for data analysis. All samples of rice were more or less contaminated with T-2 toxin but the amount did not exceed the permissible limit. Mean contamination of domestic and imported rice was 11.2 +/- 2.3 and 13 +/- 2.7 micro g/kg, respectively. Regarding imported rice, mean of contamination was 14.5 +/- 4.6 micro g/kg for the Pakistani rice and 12.6 +/- 2.2 micro g/kg for the Thai rice. There was no significant difference between domestic and imported rice, nor did we find a meaningful difference among Iranian, Pakistani and Thai rice regarding the amount of contamination [P= 0.2]. Although the amount of contamination is less than the safe limit, the extent of natural occurrence of T-2 toxin in rice in Iran indicates that contamination occurs somewhere in the production process. This, in turn, necessitates screening of rice for contamination with mycotoxins from farm to table


Sujets)
Toxine T-2/composition chimique , Contamination des aliments , Études transversales , Produits agricoles/microbiologie
6.
Journal of Zhejiang University. Science. B ; (12): 455-463, 2008.
Article Dans Anglais | WPRIM | ID: wpr-359406

Résumé

<p><b>OBJECTIVE</b>To investigate the effects of T-2 toxin on expressions of Fas, p53, Bcl-xL, Bcl-2, Bax and caspase-3 on human chondrocytes.</p><p><b>METHODS</b>Human chondrocytes were treated with T-2 toxin (1-20 ng/ml) for 5 d. Fas, p53 and other apoptosis-related proteins such as Bax, Bcl-2, Bcl-xL, caspase-3 were determined by Western blot analysis and their mRNA expressions were determined by reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Increases in Fas, p53 and the pro-apoptotic factor Bax protein and mRNA expressions and a decrease of the anti-apoptotic factor Bcl-xL were observed in a dose-dependent manner after exposures to 1-20 ng/ml T-2 toxin, while the expression of the anti-apoptotic factor Bcl-2 was unchanged. Meanwhile, T-2 toxin could also up-regulate the expressions of both pro-caspase-3 and caspase-3 in a dose-dependent manner.</p><p><b>CONCLUSION</b>These data suggest a possible underlying molecular mechanism for T-2 toxin to induce the apoptosis signaling pathway in human chondrocytes by regulation of apoptosis-related proteins.</p>


Sujets)
Humains , Apoptose , Séquence nucléotidique , Technique de Western , Caspase-3 , Génétique , Métabolisme , Prolifération cellulaire , Cellules cultivées , Chondrocytes , Biologie cellulaire , Métabolisme , Amorces ADN , Génétique , Expression des gènes , Protéines proto-oncogènes c-bcl-2 , Génétique , Métabolisme , ARN messager , Génétique , Métabolisme , RT-PCR , Transduction du signal , Toxine T-2 , Toxicité , Protéine p53 suppresseur de tumeur , Génétique , Métabolisme , Protéine Bax , Génétique , Métabolisme , Protéine bcl-X , Génétique , Métabolisme , Antigènes CD95 , Génétique , Métabolisme
7.
Journal of Zhejiang University. Science. B ; (12): 22-33, 2008.
Article Dans Anglais | WPRIM | ID: wpr-277315

Résumé

<p><b>OBJECTIVE</b>To identify the relationship between T-2 toxin and Kashin-Beck disease (KBD), the effects of T-2 toxin on aggrecan metabolism in human chondrocytes and cartilage were investigated in vitro.</p><p><b>METHODS</b>Chondrocytes were isolated from human articular cartilage and cultured in vitro. Hyaluronic acid (HA), soluble CD44 (sCD44), IL-1beta and TNF-alpha levels in supernatants were measured by enzyme-linked immunosorbent assay (ELISA). CD44 content in chondrocyte membrane was determined by flow cytometry (FCM). CD44, hyaluronic acid synthetase-2 (HAS-2) and aggrecanases mRNA levels in chondrocytes were determined using reverse transcription polymerase chain reaction (RT-PCR). Immunocytochemical method was used to investigate expressions of BC-13, 3-B-3(-) and 2-B-6 epitopes in the cartilage reconstructed in vitro.</p><p><b>RESULTS</b>T-2 toxin inhibited CD44, HAS-2, and aggrecan mRNA expressions, but promoted aggrecanase-2 mRNA expression. Meanwhile, CD44 expression was found to be the lowest in the chondrocytes cultured with T-2 toxin and the highest in control plus selenium group. In addition, ELISA results indicated that there were higher sCD44, IL-1beta and TNF-alpha levels in T-2 toxin group. Similarly, higher HA levels were also observed in T-2 toxin group using radioimmunoprecipitation assay (RIPA). Furthermore, using monoclonal antibodies BC-13, 3-B-3 and 2-B-6, strong positive immunostaining was found in the reconstructed cartilage cultured with T-2 toxin, whereas no positive staining or very weak staining was observed in the cartilage cultured without T-2 toxin. Selenium could partly inhibit the effects of T-2 toxin above.</p><p><b>CONCLUSION</b>T-2 toxin could inhibit aggrecan synthesis, promote aggrecanases and pro-inflammatory cytokines production, and consequently induce aggrecan degradation in chondrocytes. These will perturb metabolism balance between aggrecan synthesis and degradation in cartilage, inducing aggrecan loss in the end, which may be the initiation of the cartilage degradation.</p>


Sujets)
Humains , Cartilage articulaire , Métabolisme , Cellules cultivées , ADN , Cytométrie en flux , Antigènes CD44 , Immunohistochimie , Interleukine-1 bêta , Protéoglycanes , Métabolisme , RT-PCR , Sélénium , Pharmacologie , Toxine T-2 , Toxicité , Facteur de nécrose tumorale alpha
8.
Indian J Exp Biol ; 2006 Jan; 44(1): 86-8
Article Dans Anglais | IMSEAR | ID: sea-60616

Résumé

Administration of dietary T-2 toxin in 120 days old broiler chicks led to significant lower body weights and increase in feed conversion ratio from 2nd week of age. There was significant reduction in haemoglobin and packed cell volume in T-2 toxicated birds at 4 ppm level only. The other hematological parameters like TEC, TLC and absolute leucocyte count did not showed any variation due to T-2 toxin in feed. Significant reduction in serum total protein and cholesterol levels and rise in serum uric acid and LDH levels of broilers were observed due to dietary T-2 toxin. The result suggests that T-2 toxin is toxic to broilers even at very low concentrations.


Sujets)
Animaux , Protéines du sang/effets des médicaments et des substances chimiques , Poulets/sang , Hémoglobines/métabolisme , Toxine T-2/administration et posologie , Prise de poids/effets des médicaments et des substances chimiques
9.
Acta Academiae Medicinae Sinicae ; (6): 382-385, 2006.
Article Dans Chinois | WPRIM | ID: wpr-281192

Résumé

<p><b>OBJECTIVE</b>To study the effect of butenolide (BUT) on cultured chondrocytes differentiation and the possible protective effects of selenium (Se).</p><p><b>METHODS</b>Ex-vivo cultured chondrocytes were divided into six groups: (1) Control group (without BUT and Se); (2) Se 0.1 microg/ml control group; (3) BUT 0.1 microg/ml group; (4) BUT 1.0 microg/ml group; (5) BUT 5.0 microg/ml group; and (6) BUT 1.0 microg/ml + Se 0.1 microg/ml group. The expression of collagen II (Col II), collagen X (ColX), basic fibroblast growth factor (bFGF), and parathyroid hormone-related peptide (PTHrP) in (or around) chondrocytes in all groups were analyzed by immunohistochemistry.</p><p><b>RESULTS</b>The expressions of Col II in 1.0 microg/ml BUT group and 5.0 microg/ml BUT group were significantly lower than those in the control group (P < 0.05). The expression of Col II in 1.0 microg/ml BUT + Se group were significantly higher than those in the 1.0 microg/ml BUT group and 5.0 microg/ml BUT group (P < 0.05). The expressions of bFGF and PTHrP of BUT groups were significantly higher than those in the Se and control groups (P < 0.05). No expression of ColX was observed in all groups.</p><p><b>CONCLUSION</b>BUT can affect the collagen II synthesis of the chondrocytes. Selenium supplementation may play a protective role.</p>


Sujets)
Humains , 4-Butyrolactone , Pharmacologie , Différenciation cellulaire , Cellules cultivées , Chondrocytes , Biologie cellulaire , Agents protecteurs , Pharmacologie , Sélénium , Pharmacologie , Toxine T-2 , Toxicité
10.
Journal of Southern Medical University ; (12): 381-385, 2006.
Article Dans Chinois | WPRIM | ID: wpr-255305

Résumé

<p><b>OBJECTIVE</b>To study the inhibitory effect of T-2 toxin on the expression of aggrecan and collagen II in chondrocytes and the protection of selenium against this effect.</p><p><b>METHODS</b>Human chondrocytes cultured in vitro were treated with T-2 toxin at different concentrations for varied time periods (1-5 days), and the cell viability was measured by MTT assay. Aggrecan expression was detected by toluidine blue staining and collagen II expression by immunostaining using monoclonal antibody of collagen. Aggrecan and collagen II mRNA expressions were measured by semiquantitative RT-PCR.</p><p><b>RESULTS</b>T-2 toxin dose- and time-dependently affected chondrocyte viability within the concentration range of 0.001-2 mg/L, the prolonged treatment time further enhanced the dose dependence of the inhibitory effect. T-2 toxin lowered aggrecan and collagen II synthesis in the chondrocytes and reduced their mRNA expressions. Selenium could partly attenuate the inhibitory effects of T-2 toxin on aggrecan mRNA expression, but showed no such effect against T-2-induced collagen II expression.</p><p><b>CONCLUSION</b>T-2 toxin can obviously inhibit aggrecan and collagen II synthesis in human chondrocytes, and selenium can partly antagonize the inhibitory effects of T-2 toxin on aggrecan.</p>


Sujets)
Humains , Agrécanes , Génétique , Cellules cultivées , Chondrocytes , Biologie cellulaire , Métabolisme , Collagène de type II , Génétique , Relation dose-effet des médicaments , Foetus , Agents protecteurs , Pharmacologie , ARN messager , Génétique , Sélénium , Pharmacologie , Toxine T-2 , Toxicité
11.
Southeast Asian J Trop Med Public Health ; 2003 Dec; 34(4): 899-905
Article Dans Anglais | IMSEAR | ID: sea-32598

Résumé

Effects of elephant garlic (Allium ampeloprasum) volatile oil (GVO) and trichothecene (T-2) toxin were studied in Swiss albino mice. The animals were 1) topically applied GVO, 2) topically applied T-2 toxin, 3) topically applied GVO followed by T-2 toxin (GVO/T-2), and 4) T-2 toxin application followed by GVO (T-2/GVO) on the right footpad. All animals were observed by Langerhans cell enumeration and pathological changes of the footpad on days 1, 3, 5 and 7. The number of Langerhans cells in the GVO treated group (1,097 +/- 33/mm2 to 1,624 +/- 19/mm2) was not significantly different when compared with the corresponding control left footpad (1,143 +/- 33/mm2 to 1,674 +/- 21/mm2). Langerhans cells density in T-2 toxin treated group (629 +/- 29/mm2to 1,090 +/- 31/mm2) was reduced by 20-35% of the opposite control footpad (962 +/- 40/mm2 to 1,392 +/- 29/mm2). Furthermore, GVO/T-2 and T-2/GVO treated mice showed a decrease in Langerhans cell number than a single T-2 toxin treated group. While Langerhans cells in T-2 toxin, GVO/T-2 and T-2/GVO groups revealed a smaller cell size with shortening dendritic processes when compare to the normal control group. Histopathological findings of the footpad skin in T-2 toxin treated group revealed epidermal desquamation and necrosis with edema and inflammatory cells infiltration. While GVO/T-2 and T-2/GVO showed a similar sequence but a lesser severe degree. These findings suggested that GVO both in pre- and posttreatment could protect T-2 toxin induced epidermal damage in a mouse footpad.


Sujets)
Animaux , Ail , Cellules de Langerhans/effets des médicaments et des substances chimiques , Mâle , Souris , Huile essentielle/pharmacologie , Huiles végétales/pharmacologie , Répartition aléatoire , Peau/effets des médicaments et des substances chimiques , Toxine T-2/pharmacologie
12.
Rev. Inst. Adolfo Lutz ; 62(2): 95-104, 2003. tab
Article Dans Portugais | LILACS, SES-SP | ID: lil-383428

Résumé

Os tricotecenos são um grupo de micotoxinas sesquiterpenóides produzidas por várias espécies de fungos, como Fusarium, Stachybotris, Trichothecium, Trichoderma e Myrothecium. Estes tricotecenos são relativamente estáveis aos principais processos e dificilmente são removidos dos grãos contaminados sob condições moderadas. O desoxinivalenol (DON) é o tricoteceno mais frequentemente detectado. Outro é a toxina T-2, um tricoteceno do grupo A, frequentemente encontrado em cereais, que tem sido bastante estudado por ser dez vezes mais tóxico que o DON. No presente trabalho, foi adaptado e avaliado um método para determinação simultânea da toxina T-2 e de DON por cromatografia de camada delgada (ccd). A matriz empregada para o desenvolvimento do procedimento foi o malte cervejeiro. Foram estudados sistemas de extração e purificação dos extratos, eluentes e agentes reveladores. Posteriormente o método foi apolicado em amostra de arros e farinha de trigo. O limite detecção do método foi de 40 ng/ mancha para toxina T-2 e 50 ng/ mancha para DON; a recuperação média foi de 77, 9 por cento e 80,5 por cento, respectivamente para cada toxina. Foram detectdadas contaminadas uma amostra de arroz branco com 2656 ug. Kg-1 e duas de farinha de trigo com 128 e 323 ug.Kg-1 de DON


Sujets)
Toxine T-2 , Trichothécènes
13.
Arq. bras. med. vet. zootec ; 53(3): 332-340, jun. 2001. ilus, tab
Article Dans Portugais | LILACS | ID: lil-306382

Résumé

Foi testada a habilidade da toxina T-2, produzida por Fusarium sporotrichioides Sherb e veiculada por milho experimentalmente contaminado, em induzir alteraçöes da placa epifisária proximal do tibiotarso de frangos de corte. Pintos de um dia, todos machos e da linhagem Hubbard, foram alimentados com raçäo básica a base de milho e soja, na qual todo o milho foi substituído por milho contaminado, contendo exclusivamente T-2 na quantidade de 2,64mg/Kg. Um outro grupo alimentado com milho näo contaminado serviu como testemunha e ambos foram observados por três períodos (7, 14 e 21 dias). Independente do período e da quantidade de T-2 ingerida (0,3 a 1,9mg/Kg), o tibiotarso dos animais tratados mostrou maturaçäo e diferenciçäo defectivas de condrócitos, lesöes vasculares e penetraçäo vascular de cartilagem, todas similares às da discondroplasia tibial. Conclui-se que a toxina T-2 oriunda de Fusarium sporotrichioides Sherb é capaz de induzir lesöes básicas e iniciais da discondroplasia tibial em frangos de corte


Sujets)
Animaux , Mâle , Oiseaux , Ostéochondrodysplasies , Toxine T-2
14.
Arq. bras. med. vet. zootec ; 53(1): 66-70, fev. 2001. ilus, tab
Article Dans Portugais | LILACS | ID: lil-290498

Résumé

Determinaram-se a histomorfometria e a funçäo da tireóide de frangos de corte após ingestäo de toxina T-2 de Fusarium sporotrichioides, veiculada na raçäo por curto período. Foram utilizados 30 pintos da linhagem Hubbard, todos machos e com um dia de idade, distribuídos ao acaso em dois grupos. 0 grupo tratado recebeu raçäo contaminada com 2,64 mg/kg de toxina T-2 e o grupo controle, raçäo livre de qualquer toxina. Cinco animais de cada grupo foram sacrificados aos 7, 14 e 21 dias após o início do tratamento, momentos em que foram colhidos plasma para dosagem de tiroxina livre e tireóides para avaliaçäo histomorfométrica. As tireóides dos frangos do grupo tratado sacrificados aos 7 e 14 dias apresentaram prevalência de folículos pequenos com epitélio baixo, confirmada pela morfometria. Aos 21 dias acentuaram-se as diferenças com o grupo controle, observando-se três tireóides com características de bócio parenquimatoso e duas com bócio colóide. O nível sérico de tiroxina livre no grupo tratado foi significativamente menor, mas apenas aos 14 dias. Conclui-se que a toxina T2 é agente potencialmente bociogênico, capaz de alterar a histomorfometria da tireóide e os níveis plasmáticos de tiroxina e se ingerida por curto período de tempo e em doses reduzidas permite à tireóide manter seu estado de eutireoidismo


Sujets)
Animaux , Mâle , Fusarium , Volaille , Toxine T-2 , Glande thyroide
15.
Rev. Inst. Adolfo Lutz ; 60(2): e35803, 2001. tab, graf
Article Dans Portugais | LILACS, ColecionaSUS, SES-SP, CONASS, SESSP-ACVSES, SESSP-IALPROD, SES-SP, SESSP-IALACERVO | ID: lil-339399

Résumé

Sistemas de extraçäo e limpeza foram avaliados para a determinaçäo de tricotecenos em milho por cromatografia gasosa com detector de ionizaçäo de chama. O método de extraçäo e limpeza descrito por Furlong & Soares (1995), combinado com uma coluna de limpeza preconizada pr Romer (1986), foi o sistema que apresentou melhores resultados. Para extraçäo foi usado metanol:cloreto de potássio 4 por cento (9:1) seguido por clarificaçäo com sulfato de amônio 30 por cento e partiçäo com diclorometano. A seguir, o extrato foi passado pela coluna de alumina:carväo (2,3:1,9) e os tricotecenos eluídos com acetonitrila:água (84:16). O extrato, após reaçäo de derivaçäo com anidrido trifluoroacético (TFAA) em piridina, foi injetado em um cromatógrafo a gás com detector por ionizaçäo em chama. As recuperaçöes médias obtidas foram 72 por cento para desoxinivalenol (DON), 88 por cento para diacetoxiscirpenol (DAS) e 87 por centopara toxina T2(T2). Os limites de detecçäo obtidos foram 30 ng/g pra DON, 50 ng/g para DAS e 40 ng/g para toxina foram 9,8,6,3 e 6,6 por cento para DON,DAS e T2, respectivamente. (AU)


Extraction and cleanup systems were evaluated for the determination of trichothecenes incorn by gas chromatography with flame ionization detector. The extraction and cleanup method describedby Furlong & Soares (1995), combined with the Romer (1986) cleanup column exhibited the best results.The extraction used methanol: 4% potassium chloride (9:1), followed by a clarification with 30% ammoniumsulfate, and partition with dichloromethane.The extract was then passed through an alumina:carboncolumn (2.3:1.9) and eluted with acetonitrile:water (84:16). Trifluoroacetic anhydride in the presence ofpyridine was used for derivatization before injection in a gas chromatograph with an ionization detector.The average recoveries were 72% for deoxynivalenol (DON), 88% for diacetoxyscirpenol (DAS) and 87%for toxin T2 (T2). The detection limits were 30 ng/g for DON, 50 ng/g for DAS and 40 ng/g for T2. Theaverage coefficients of variation for spiked samples at the 500 ng/g level were 9.8, 6.3 e 6.6% for DON,DAS, and T2, respectively. (AU)


Sujets)
Toxine T-2 , Trichothécènes , Chromatographie en phase gazeuse , Mycotoxines , Zea mays
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