992 resultados para Fumonisina B1


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Introduction - Milk is considered a complete food from the nutritional point of view. Milk can be exposed to various types of contamination, such as mycotoxins. These metabolites are naturally occurring toxic compounds produced by fungi. Several studies on milk samples have reported the presence of aflatoxin B1 (AFB1) and M1 (AFM1), due to the high incidence in samples intended for human consumption, carcinogenicity proven AFB1 and resistance of the contaminants to the process of digestion, making those available for intestinal absorption. Considering these aspects, the objective of this study was to evaluate the genotoxicity of milk samples contaminated by AFB1 and AFM1 before and after the action of lactic acid bacteria using Caco-2 intestinal human cells.

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Aflatoxin B1 (AFB1) is a secondary metabolite produced by the fungi Aspergillus flavus and is the most potent hepatocarcinogen known in mammals and has been classified by the International Agency of Research on Cancer as Group 1 carcinogen. Although dietary exposure to AFB1 has been extensively documented, there are still few studies dedicated to the problem of occupational exposure. Considering recent findings regarding AFB1 occupational exposure in poultry production, it was considered relevant to clarify if there is also exposure in poultry slaughterhouses. Occupational exposure assessment to AFB1 was done with a biomarker of internal dose that measures AFB1 in the serum by enzyme-linked immunosorbent assay. Thirty workers from a slaughterhouse were enrolled in this study. A control group (n = 30) was also considered in order to know AFB1 background levels for Portuguese population. Fourteen workers (47.0%) showed detectable levels of AFB1 with values from 1.06 to 4.03ng ml(-1), with a mean value of 1.73ng ml(-1). No AFB1 was detected in serum of individuals used as controls. Despite uncertainties regarding the exposure route that is contributing more to exposure (inhalation or dermal) is possible to state that exposure to AFB1 is occurring in the slaughterhouse studied. It seems that reducing AFB1 contamination in poultry production can have a positive result in this occupational setting.

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Dissertação composta por 02 artigos.

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El trabajo presentado es de tipo investigaci?n experimental en el que se hace una intervenci?n a una poblaci?n de deportistas que conforman la selecci?n Valle masculina de f?tbol sala en situaci?n de discapacidad visual. Se dise?? una propuesta de actividades adaptadas orientadas a la preparaci?n f?sica, en las que se tiene en cu?ntalas caracter?sticas y necesidades espec?ficas de los deportistas, los medios y los recursos que permiten el acceso a la informaci?n, la complejidad y dificultad de las actividades de acuerdo a su situaci?n de discapacidad visual. Finalmente, valora e identifica el nivel de variaci?n de las capacidades f?sicas trabajadas, mediante la realizaci?n de unos test de evaluaci?n al inicio y el final del proceso, lo que permite determinar el nivel de ?xito logrado en la aplicaci?n de la propuesta. Esta investigaci?n comprende tres cap?tulos en los cuales; en el primer cap?tulo se trataron temas como concepto de discapacidad, actividad f?sica adaptada, deporte adaptado, capacidades condicionales y coordinativas en los deportistas de f?tbol sala con deficiencia visual. En el segundo cap?tulo se encuentra el tema del trabajo, el problema, la justificaci?n del tema y los objetivos de la tesis; finalmente en el tercer cap?tulo se habla de la caracterizaci?n del grupo del seleccionado del Valle de f?tbol sala, los protocolos de los test que se llevaron a cabo, los resultados, an?lisis de las pruebas, y la conclusi?n general del trabajo de investigaci?n.

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Syftet med avhandlingen har varit att granska finska inlärares konnektorbruk på CEFR-nivåerna A1, A2 och B1 longitudinellt ur ett funktionellt perspektiv. Jag har studerat vad som är kännetecknande för konnektorbruket på dessa CEFR-nivåer och i vilken funktion konnektorerna har använts på dessa nivåer. Vidare har jämförts konnektorbruket i materialet med det som sägs i CEFR-kriterierna. Slutligen har jag också granskat hur konnektorbruket utvecklas. Som material har jag använt berättande texter (n=303) skrivna av 101 finskspråkiga grundskolelever och gymnasister. Materialet ingår i projektet Topling – Inlärningsgångar i andraspråket vid Jyväskylä universitet. I avhandlingen har använts såväl kvantitativa som kvalitativa metoder. Jag har räknat konnektorernas och konnektorkategoriernas frekvenser samt analyserat i vilka funktioner konnektorerna har använts. I den funktionella analysen har använts systemisk-funktionell lingvistik (Halliday & Matthiessen 2004) samt Labovs (1972) modell om berättelsestrukturen. Analysen har visat att konnektorbruket skiljer sig mellan CEFR-nivåerna A1, A2 och B1. Antalet konnektorer ökar såväl från nivå A1 till A2 som från nivå A2 till nivå B1 och andelen additiva och målspråksavvikande konnektorer minskar medan andelen temporala, kausala och komparativa konnektorer samt att ökar. Konnektorerna har använts först och främst i deras prototypiska funktioner på alla dessa CEFR-nivåer. Vissa konnektorer (när, eftersom, att) verkar även ha en funktion i berättelsestrukturen. Om man jämför konnektorbruket med CEFR-kriterierna kan man konstatera att inlärare på nivå A1 använder pronomenet den i stället för sedan även om denna konnektor nämns i CEFR-kriterierna på nivå A1. Konnektorbruket verkar utvecklas på det sättet att antalet konnektorer samt andelen additiva, temporala och komparativa konnektorer samt att ökar. Andelen additiva konnektorer och målspråksavvikande konnektorer minskar. Vidare börjar inlärare använda mera olika konnektorer och på nivå B1 även mindre frekventa konnektorer som om och fast. I fortsättningen borde man granska konnektorbruket i olika texttyper samt studera om explicit undervisning påverkar inlärares konnektorbruk.

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Kidney transplantation has been recognised as the optimal treatment choice for most end stage renal disease patients and the increase of allograft survival rates is achieved through the refinement of novel immunosuppressive agents. Chronic Graft Disease (CGD) is a multifactorial process that likely includes a combination of immunological, apoptotic and inflammatory factors. The application of individualised immunosuppressive therapies will also depend on the identification of risk factors that can influence chronic disease. Despite being the subject of several independent studies, investigations of the relationship between transforming growth factor-b1 (TGF-b1) polymorphisms and kidney graft outcome continue to be plagued by contradictory conclusions.

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Laccases (LCs) are multicopper oxidases that find application as versatile biocatalysts for the green bioremediation of environmental pollutants and xenobiotics. In this study we elucidate the degrading activity of Lac2 pure enzyme form Pleurotus pulmonarius towards aflatoxin B1 (AFB1) and M1 (AFM1). LC enzyme was purified using three chromatographic steps and identified as Lac2 through zymogram and LC-MS/MS. The degradation assays were performed in vitro at 25 °C for 72 h in buffer solution. AFB1 degradation by Lac2 direct oxidation was 23%. Toxin degradation was also investigated in the presence of three redox mediators, (2,2′-azino-bis-[3-ethylbenzothiazoline-6-sulfonic acid]) (ABTS) and two naturally-occurring phenols, acetosyringone (AS) and syringaldehyde (SA). The direct effect of the enzyme and the mediated action of Lac2 with redox mediators univocally proved the correlation between Lac2 activity and aflatoxins degradation. The degradation of AFB1 was enhanced by the addition of all mediators at 10 mM, with AS being the most effective (90% of degradation). AFM1 was completely degraded by Lac2 with all mediators at 10 mM. The novelty of this study relies on the identification of a pure enzyme as capable of degrading AFB1 and, for the first time, AFM1, and on the evidence that the mechanism of an effective degradation occurs via the mediation of natural phenolic compounds. These results opened new perspective for Lac2 application in the food and feed supply chains as a biotransforming agent of AFB1 and AFM1.

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BACKGROUND AND PURPOSE It has been proposed that BRL37344, SR58611 and CGP12177 activate b3-adrenoceptors in human atrium to increase contractility and L-type Ca2+ current (ICa-L). b3-adrenoceptor agonists are potentially beneficial for the treatment of a variety of diseases but concomitant cardiostimulation would be potentially harmful. It has also been proposed that (-)-CGP12177 activates the low affinity binding site of the b1-adrenoceptor in human atrium. We therefore used BRL37344, SR58611 and (-)-CGP12177 with selective b-adrenoceptor subtype antagonists to clarify cardiostimulant b-adrenoceptor subtypes in human atrium. EXPERIMENTAL APPROACH Human right atrium was obtained from patients without heart failure undergoing coronary artery bypass or valve surgery. Cardiomyocytes were prepared to test BRL37344, SR58611 and CGP12177 effects on ICa-L. Contractile effects were determined on right atrial trabeculae. KEY RESULTS BRL37344 increased force which was antagonized by blockade of b1- and b2-adrenoceptors but not by blockade of b3-adrenoceptors with b3-adrenoceptor-selective L-748,337 (1 mM). The b3-adrenoceptor agonist SR58611 (1 nM–10 mM) did not affect atrial force. BRL37344 and SR58611 did not increase ICa-L at 37°C, but did at 24°C which was prevented by L-748,337. (-)-CGP12177 increased force and ICa-L at both 24°C and 37°C which was prevented by (-)-bupranolol (1–10 mM), but not L-748,337. CONCLUSIONS AND IMPLICATIONS We conclude that the inotropic responses to BRL37344 are mediated through b1- and b2-adrenoceptors. The inotropic and ICa-L responses to (-)-CGP12177 are mediated through the low affinity site b1L-adrenoceptor of the b1-adrenoceptor. b3-adrenoceptor-mediated increases in ICa-L are restricted to low temperatures. Human atrial b3-adrenoceptors do not change contractility and ICa-L at physiological temperature.

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Although numerous genetic and acquired factors are appreciated as risk factors for venous thromboembolism (VTE) [1,2], only recently have male gender [3,4], dyslipoproteinemia [5], and silent atherosclerotic vascular disease [6] been linked to VTE. We recently found that high-density lipoprotein (HDL) deficiency is a key feature of a pattern of dyslipoproteinemia that is associated with VTE in males, and we found that the common TaqI B1 variation in the cholesteryl ester transfer protein (CETP) gene is significantly linked to VTE [5]. However, the TaqI B1/B2 single nucleotide polymorphism (SNP) itself is unlikely to affect directly CETP activity, but it is linked to nonsynonymous CETP SNPs Ala373Pro and Arg451Gln [7–9]. Here, we demonstrate that these two CETP variations are associated with VTE and low plasma HDL levels in males.

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Background-Although dyslipoproteinemia is associated with arterial atherothrombosis, little is known about plasma lipoproteins in venous thrombosis patients. Methods and Results-We determined plasma lipoprotein subclass concentrations using nuclear magnetic resonance spectroscopy and antigenic levels of apolipoproteins AI and B in blood samples from 49 male venous thrombosis patients and matched controls aged <55 years. Venous thrombosis patients had significantly lower levels of HDL particles, large HDL particles, HDL cholesterol, and apolipoprotein AI and significantly higher levels of LDL particles and small LDL particles. The quartile-based odds ratios for decreased HDL particle and apolipoprotein AI levels in patients compared with controls were 6.5 and 6.0 (95% CI, 2.3 to 19 and 2.1 to 17), respectively. Odds ratios for apolipoprotein B/apolipoprotein AI ratio and LDL cholesterol/HDL cholesterol ratio were 6.3 and 2.7 (95% CI, 1.9 to 21 and 1.1 to 6.5), respectively. When polymorphisms in genes for hepatic lipase, endothelial lipase, and cholesteryl ester transfer protein were analyzed, patients differed significantly from controls in the allelic frequency for the TaqI B1/B2 polymorphism in cholesteryl ester transfer protein, consistent with the observed pattern of lower HDL and higher LDL. Conclusions-Venous thrombosis in men aged <55 years old is associated with dyslipoproteinemia involving lower levels of HDL particles, elevated levels of small LDL particles, and an elevated ratio of apolipoprotein B/apolipoprotein AI. This dyslipoproteinemia seems associated with a related cholesteryl ester transfer protein genotype difference. © 2005 American Heart Association, Inc.

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To evaluate the timing of mutations in BRAF (v-raf murine sarcoma viral oncogene homolog B1) during melanocytic neoplasia, we carried out mutation analysis on microdissected melanoma and nevi samples. We observed mutations resulting in the V599E amino-acid substitution in 41 of 60 (68%) melanoma metastases, 4 of 5 (80%) primary melanomas and, unexpectedly, in 63 of 77 (82%) nevi. These data suggest that mutational activation of the RAS/RAF/MAPK pathway in nevi is a critical step in the initiation of melanocytic neoplasia but alone is insufficient for melanoma tumorigenesis.

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A home is an embodiment of human privacy, apart from providing shelter, security and several other functions. Achieving the desired level of privacy at home is very important in Muslim societies. Privacy is intended to protect the female members of the family from strangers, especially while entertaining guests at home. One way of controlling levels of exposure of the domestic domains to strangers is by controlling privacy levels. This research will investigate perceptions of privacy among Australian Muslims when entertaining guests at their homes. This research will also investigate the extent that modesty (achieved through both appearance and design) acts as the balancing factor in achieving a family’s desired levels of privacy while also affording them the capacity to be hospitable to guests. This research will use a qualitative approach to investigate Australian Muslim homes around Queensland, predominantly in the Brisbane area. A total number of 20 to 60 participants (10 to 30 males, 10 to 30 females) ranging from 25 to 55 years old will be interviewed. Ideally, participants will be those who have children or extended families (parents or siblings) living in the house. The data will be coded and analysed for the purpose of generating new knowledge for architects and designers when designing Muslim homes. It will also extend the current body of knowledge related to privacy mechanisms in housing designs, thereby benefitting architects and designers in the future.

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Most research virtually ignores the important role of a blood clot in supporting bone healing. In this study, we investigated the effects of surface functional groups carboxyl and alkyl on whole blood coagulation, complement activation and blood clot formation. We synthesised and tested a series of materials with different ratios of carboxyl (–COOH) and alkyl (–CH3, –CH2CH3 and –(CH2)3CH3) groups. We found that surfaces with –COOH/–(CH2)3CH3 induced a faster coagulation activation than those with –COOH/– CH3 and –CH2CH3, regardless of the –COOH ratios. An increase in –COOH ratios on –COOH/–CH3 and –CH2CH3 surfaces decreased the rate of coagulation activation. The pattern of complement activation was entirely similar to that of surface-induced coagulation. All material coated surfaces resulted in clots with thicker fibrin in a denser network at the clot/material interface and a significantly slower initial fibrinolysis when compared to uncoated glass surfaces. The amounts of platelet-derived growth factor-AB (PDGF-AB) and transforming growth factor-b (TGF-b1) released from an intact clot were higher than a lysed clot. The release of PDGF-AB was found to be correlated with the fibrin density. This study demonstrated that surface chemistry can significantly influence the activation of blood coagulation and complement system, resultant clot structure, susceptibility to fibrinolysis as well as release of growth factors, which are important factors determining the bone healing process.