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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Fumonisin exposure biomarkers in humans consuming maize staple diets

Van der Westhuizen, Liana 03 1900 (has links)
Thesis (PhD (MedSc))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Fumonisins are carcinogenic mycotoxins which occur world-wide in maize and maize-based products intended for human consumption. Consumption of fumonisin contaminated maize as a staple diet has been associated with oesophageal and liver cancer incidence as well as neural tube defects. This study has confirmed the State of Santa Catarina, Brazil as another region where the consumption of maize contaminated with fumonisins and high oesophageal cancer incidence co-occur. Since fumonisins exert their main biochemical effect by disruption of the sphingolipid biosynthetic pathway and are implicated in cancer, the role of fumonisin B1 (FB1) in FB1–induced rat hepatocyte nodules was investigated. The current study showed that FB1 exposure activated sphingosine accumulation in the nodules which could induce the bio-active sphingosine 1-phosphate to provide a selective growth stimulus on subsequent FB1 exposure. Since the FB1-induced hepatocyte nodules were not resistant to the disruption of sphingolipid biosynthesis, it was not the mechanism whereby the altered hepatocytes escaped the mitoinhibition of FB1 and selectively proliferated into hepatocyte nodules. A study in maize subsistence farming communities investigated the sphingosine and sphinganine levels in blood and urine of participants. Fumonisin exposure was assessed in these communities based on fumonisin levels in maize that was concurrently collected from the areas where the participants resided. Subsequently fumonisin exposure was assessed in individuals based on the fumonisin levels in maize collected from each household and by acquiring weighed food records for each member of the household. It was confirmed in both these studies that communities are chronically exposed to fumonisin levels well above the provisional maximum tolerable daily intake determined by the Joint FAO/WHO Expert Committee on Food Additives. Since the sphinganine and sphingosine levels in blood and urine of the participants exposed to various levels of fumonisin were not significantly different, the sphingoid bases and their ratios could not be established as a biomarker of fumonisin exposure. Therefore, an alternative biomarker of exposure was investigated during studies into a practical cost effective method to reduce fumonisin. The customary maize food preparation practices were assessed in a maize subsistence farming community and subsequently optimised to reduce the fumonisin levels in the maize under laboratory-controlled conditions. Implementation of this optimised and culturally acceptable intervention method of sorting and washing maize in a rural community reduced fumonisin contamination in home-grown maize by 84%. The intervention study attained a 62% reduction in fumonisin exposure based on fumonisin levels in maize-based food and consumption as assessed by 24-h dietary recall questionnaires. The alternative biomarker of fumonisin exposure, urinary FB1, was investigated during the intervention study. The FB1 urinary biomarker measured fumonisin intake at the individual level and confirmed the reduction achieved as assessed by food analysis and food intake data. The biomarker was thus well correlated with fumonisin exposure and confirmed the efficacy of the simple and culturally acceptable intervention method. Utilisation of the urinary FB1 biomarker and the customised hand-sorting and washing of maize to reduce fumonisin exposures has the potential to improve food safety and health in subsistence maize farming communities. / AFRIKAANSE OPSOMMING: Fumonisien is kankerverwekkende mikotoksiene wat wêreldwyd voorkom op mielies en mielie-verwante produkte bestem vir menslike verbruik. Daar is ‘n verband tussen die voorkoms van slukderm en lewer kanker, sowel as neuraalbuisdefekte, in gemeenskappe waar fumonisien-gekontamineerde mielies die stapel voedsel is. Die Brasiliaanse Staat, Santa Catarina is uitgewys as nog 'n area waar hoë voorkoms van slukdermkanker en hoë fumonisin vlakke in mielies gesamentlik voorkom. Aangesien fumonisien verbind word met van kanker en die hoof biochemiese effek die ontwrigting van die sfingolipiedbiosintese weg is, is die rol van fumonisien B1 (FB1) in FB1-geinduseerde rot hepatosietnodules ondersoek. Die studie het getoon dat FB1 blootstelling aktiveer sfingosien ophoping in die hepatosietnodules wat moontlik die bio-aktiewe sfingosien 1-fosfaat aktiveer om op daaropvolgende FB1 blootstellings geselekteerde groei stimulasie te ondergaan. Die FB1-geïnduseerde hepatosietnodules was nie bestand teen die inhibisie van die sfingolipied biosintese nie en dus nie die meganisme waardeur die veranderde hepatosiete mito- inhibisie van FB1 vryspring, en selektief ontwikkel in hepatosietnodules nie. ‘n Studie in bestaansboerdery gemeenskappe het die sfingosien en sfinganien vlakke in bloed en uriene vergelyk met individuele fumonisien blootstelling. Laasgenoemde is gebaseer op fumonisien vlakke in gekolleekterde mielies vanuit die deelnemers se huise en aannames vanuit die literatuur. Die opvolg studie in die areas het individuele fumonisien blootstelling bepaal gebaseer op fumonisien vlakke in die mielies van elke huishouding en die inname van mielies deur die voedsel van elke individu te weeg. Albei hierdie studies het bevestig dat die gemeenskappe blootgestel is aan kroniese fumonisien vlakke wat die maksimum toelaatbare daaglikse inname wat deur die gesamentlike FAO/WHO deskundige komitee op voedsel toevoegsels vasgestel is, oorskei. Aangesien die sfingosien en sfinganien vlakke nie beduidend verskil in bloed of uriene van mense wat aan verskillende fumonisien-kontaminasie vlakke blootgestel is nie, kan die lipiedbasisse en hul verhouding nie as ‘n biologiese merker vir fumonisien blootstelling bevestig word nie. Dus is ‘n alternatiewe biologiese merker vir fumonisien blootstelling ondersoek gedurende ‘n studie oor praktiese bekostigbare maniere om fumonisin blootstelling te verlaag. Die tradisionele voedsel voorbereidingspraktyke in ‘n bestaansboerdery gemeenskap is bestudeer en onder laboratorium-gekontroleerde toestande aangepas om fumonisien vlakke in die mielies optimaal te verlaag. Die kultureel aanvaarbare intervensie metode, sortering en was van die mielies, is in ‘n bestaansboerdery gemeenskap toegepas waar ‘n 84% verlaging in fumonisien vlakke van die mielies verkry is. Die intervensie metode het ‘n 62% verlaging in fumonisien blootstelling te weeggebring deur fumonisien vlakke in die mieliegebasserde disse te meet en inname daarvan deur die deelnemers met 24-h diëetkundige vraelyste vas t e stel. Gedurende die intervensie studie is urienêre FB1, die alternatiwe biologiese merker van fumonisien blootstelling, ondersoek. Individuele fumonisien blootstelling data, bepaal met die urienêre FB1 biomerker, het goed ooreengestem met die voedsel analise en voedsel inname data en het dus die doeltreffendheid van die praktiese kultuur aanvaarbare intervensie metode bevestig. Benutting van die FB1 urienêre biologies merker en die optimale sortering en was van die mielies om die fumonisien blootstelling te verlaag het die potensiaal om voedselveiligheid en gesondheid in hierdie bestaansboerdery gemeenskappe aansienlik te verbeter.
32

Efeitos genotóxico e citotóxico ex vivo da Micotoxina fumonisina b1 em leucócitos humanos

Kaminski, Taís Fernanda Andrzejewski 21 February 2017 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-20T18:20:05Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TAIS FERNANDA ANDRZEJEWSKI KAMINSKI.pdf: 736237 bytes, checksum: 7739abe4dcd9ebf1aa4595b41498419a (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-20T18:20:34Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TAIS FERNANDA ANDRZEJEWSKI KAMINSKI.pdf: 736237 bytes, checksum: 7739abe4dcd9ebf1aa4595b41498419a (MD5) / Made available in DSpace on 2017-06-20T18:20:34Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TAIS FERNANDA ANDRZEJEWSKI KAMINSKI.pdf: 736237 bytes, checksum: 7739abe4dcd9ebf1aa4595b41498419a (MD5) Previous issue date: 2017-02-21 / Os fungos produzem vários metabólitos secundários, onde muitos destes têm sido associados com a indução de efeitos tóxicos em animais e seres humanos. O efeito toxicológico, incluindo o carcinogênico, tem sido observado em mais de 300 micotoxinas estruturalmente conhecidas. As Fumonisinas são micotoxinas produzidas principalmente por Fusarium verticillioides e Fusarium proliferatum, as quais frequentemente contaminam vários alimentos, especialmente milho e seus derivados, induzindo ao aparecimento de quadros patológicos em humanos. A Fumonisina B1 (FB1) é a mais prevalente, respondendo por aproximadamente 70% do total das micotoxicoses. Esta micotoxina está associada com leucoencefalomalácia (LEM) em cavalos, edema pulmonar em suínos e hepatocarcinoma em ratos, além de estar relacionada à inibição da biossíntese de esfingolípideos e ao aumento do risco de cancro esofágico em seres humanos. O presente estudo teve como objetivo investigar os efeitos citotóxico e genotóxico da fumonisina B1 através do teste de viabilidade celular e do teste de proliferação celular em cultura de leucócitos humanos. As concentrações testadas foram de 200; 100; 50; 5; 0,5; 0,05; 0,005 μg/mL e 300; 30; 3; 1; 0,1; 0,01 fg/mL. Todos os ensaios foram realizados em triplicatas sendo que, como controle positivo foi utilizado H2O2 4mM e, como controle negativo, tampão PBS 7,4. Com exceção das concentrações de 3fg/mL, 0,1fg/mL e 0,01fg/mL, todas as concentrações testadas demonstraram ser citotóxicas (p<0,05). Em relação ao teste de genotoxicidade, exceto as concentrações de 0,1fg/mL e 0,01fg/mL, demonstraram interferir significativamente na proliferação celular. Podemos concluir, de forma inédita, que somente em concentrações extremamente baixas, na ordem de fentogramas por mililitro, a Fumonisina B1 diminuiu os danos induzidos em leucócitos humanos. / Fungi produce several secondary metabolites, where many of these have been associated with the induction of toxic effects in animals and humans. The toxicological effect, including the carcinogenic, has been observed in more than 300 structurally known mycotoxins. Fumonisins are mycotoxins produced mainly by Fusarium verticillioides and Fusarium proliferatum, which often contaminate various foods, especially corn and its derivatives, leading to the appearance of pathological conditions in humans. Fumonisin B1 (FB1) is the most prevalent, accounting for approximately 70% of the total mycotoxicosis. This mycotoxin is associated with leukoencephalomalacia (LEM) in horses, pulmonary edema in pigs and hepatocarcinoma in rats, besides being related to the inhibition of sphingolipid biosynthesis and to the increasing risk of esophageal cancer in humans.The present study aimed to investigate the cytotoxic and genotoxic effects of fumonisin B1 through the cell viability and the cell proliferation test in human leukocyte culture. The tested concentrations tested were 200; 100; 50; 5; 0,5; 0,05; 0,005 μg/mL e 300; 30; 3; 1; 0,1; 0,01 fg/mL. All the tests were performed in triplicates,and it was used H2O2 4mM as a positive control, and PBS 7.4 bufferas a negative control. All concentrations tested were cytotoxic (p <0.05), except the 3fg/mL, 0,1fg/mL and 0,01fg/mL concentrations. Regarding to the genotoxicity test, except the 0.1fg/mL and 0.01fg/mL concentrations of, they demonstrated to significantly interfere in the cell proliferation. In an unprecedented way , it can be concludedthat only in extremely low concentrations, in the order of phentograms per milliliter, the Fumonisin B1 decreased the induced damage in human leukocytes.
33

THE SUPPORT OF GENE EXPRESSION IN UNDERSTANDING SECONDARY METABOLITE PRODUCTION AND ECOLOGY IN FUSARIUM VERTICILLIOIDES

LAZZARO, IRENE 23 February 2012 (has links)
Il tema principale di questa tesi di dottorato verte sul metabolismo secondario di F. verticillioides, con particolare interesse alla via biosintetica, produzione e mascheramento delle fumonisine B (FB), fumonisine A (FA), fumonisine C (FC) e bikaverina, studiati in relazione all’ecologia fungina. E’ stato osservato che l’acqua libera (aw) esercita un effetto significativo maggiore rispetto alla temperatura sul metabolismo secondario di F. verticillioides. Alti valori di aw favoriscono l’espressione dei geni FUM ed una maggiore sintesi delle FB, FA e FC. Inoltre la produzione di bikaverina e l’espressione di BIK1 sono influenzate dall’ aw nello stesso modo che la produzione di FB e l’espressione dei geni FUM. Anche il tempo di incubazione è un fattore critico per la produzione di FB in F. verticillioides, così come per F. proliferatum: la produzione di FB, FA e FC aumenta nel tempo fino a 30 giorni, periodo dopo il quale si notano differenze tra le due specie fungine. Riguardo le fumonisine nascoste, queste sono state ritrovate in colture sia di F. verticillioides che di F. proliferatum. Non è stata registrata sintesi alcuna in colture cresciute su substrato di crescita sintetico, ma al contrario solo su colture cresciute su substrato a base di mais. / The main topic of this PhD thesis is F. verticillioides secondary metabolism, with regard to fumonisin B (FB), fumonisin A (FA), fumonisin C (FC) and bikaverin biosynthetic pathways and production and masking, studied in relation to fungal ecology. What we found is that water activity (aw) has a more significant effect than temperature on F. verticillioides secondary metabolism. Moreover bikaverin production and BIK1 expression are influenced by aw in the same way as FB production and FUM gene expression respectively. High aw levels favour FUM gene expression and allow the highest synthesis of FB, FA and FC. Incubation time is also critical for FB production both for F. verticillioides and F. proliferatum: the general trend is that FB, FA and FC production increases with time, up to 30 days, period after which differences can be noticed between F. verticillioides and F. proliferatum. As regard masked fumonisins, they are recovered in F. verticillioides and also F. proliferatum cultures, furthermore no synthesis is observed on cultures grown on synthetic medium, but only in those grown on maize-based substrates.
34

Interação entre Lipopolissacarídeo de Salmonella Typhimurium e Fumonisina B1 em frangos de corte

Rauber, Ricardo Hummes January 2012 (has links)
Lipopolissacarídeo (LPS) é o principal componente da parede celular de bactérias Gram-negativas, sendo liberado durante a divisão celular ou morte da bactéria após lise. O LPS é um dos mais potentes ativadores do sistema imune, desencadeando uma resposta inflamatória inespecífica. A exposição ao LPS tem sido associada a uma gama de efeitos tóxicos em frangos e outras aves, como hipertermia, inflamação, caquexia e, eventualmente, morte. A fumonisina B1 (FB), um metabólito secundário produzido pelo Fusarium verticilloides, tem sido descrita como causa de doenças previamente conhecidas (leucoencefalomalácea equina e edema pulmonar suíno), bem como causando alguns efeitos em aves. Os principais sinais clínicos da intoxicação por FB em frangos são desempenho reduzido, ascite, edema e congestão dos rins, diarreia, peso relativo do fígado aumentado e mortalidade. O objetivo deste trabalho foi avaliar os efeitos individuais e combinados do LPS de Salmonella Typhimuruim (sLPS) e FB sobre o desempenho produtivo (peso corporal [PC], consumo de ração [CR] e conversão alimentar [C]), peso relativo de fígado (PRF), parâmetros biológicos (proteínas plasmáticas totais [PPT], albumina [Alb], cálcio [Ca], triglicerídeos [Tri], colesterol total [Col], fósforo [P], ácido úrico [AU], proteína C-reativa [CRP], alanina aminotransferase [ALT], aspartato aminotransferase [AST], fosfatase alcalina [FA], gama glutamiltransferase [GGT] e relação esfinganina/esfingosina [SA:SO]), avaliação morfológica do intestino delgado (altura de vilosidades [AV], profundidade de criptas [PC] e relação vilosidade/cripta [V:C]) e avaliações histológicas de vários tecidos de 432 frangos de corte, machos, com um dia de idade, divididos em nove tratamentos, conforme a dose de FB (0, 100 ou 200 mg/kg, do primeiro ao 28º dia de experimento) e sLPS (0, 250 ou 500 μg/ave por aplicação, a cada 48 horas, do 15º ao 27º dia. Ao final do experimento (28 dias): efeitos significativos do sLPS foram observados sobre PC, Ca, Col, P, AU, CRP, AST, FA e AV; efeitos significativos da FB foram observados sobre PC, CR, C, PRF, PPT, Alb, Ca, Tri, Col, AU, CRP, ALT, GGT, SA:SO, AV e V:C; efeitos significativos da interação sLPS*FB foram observados sobre PRF, Alb, Col, P, AU e CRP. Alterações histológicas foram observadas para sLPS, FB e sLPS*FB no fígado e rins. De acordo com estes resultados, sLPS e FB (isolados ou associados) determinam efeitos sobre o desempenho e parâmetros biológicos de frangos de corte. / Lipopolysaccharide (LPS) is the main component of Gram-negative bacterial cell wall, and is released during cellular division or bacterial death after lysis. This is one of the most powerful activators of the immune system, leading to a non-specific inflammatory response. LPS exposure has been related to a role of effects in broilers and other avian species, such as hyperthermia, inflammation, cachexia, and eventually, death. Fumonisin B1 (FB), a secondary metabolite produced by Fusarium verticilloides, has been shown to be associated to some previously known diseases or syndromes (equine leucoencephalomalacea and porcine pulmonary edema) and has also been described as causing some effects in poultry. The main clinical signs of FB intoxication in broilers are reduced productive performance, ascites, kidney edema and congestion, diarrhea, increased relative weight of the liver, and mortality. The aim of this research was to evaluate the individual and combined effects of Salmonella Typhimurium Lipopolysaccharide (sLPS) and FB on performance (body weight, feed intake, and feed conversion rate), relative weight of the liver, biological parameters (total plasma proteins [TPP], albumin [Alb], calcium [Ca], triglycerides [Tri], total cholesterol [Col], phosphorus [Ph], uric acid [UA], C-reactive protein [CRP], alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [AP], gamma glutamiltransferase [GGT] and sphinganine-to-sphingosine [SA:SO] ratio), morphological evaluation of jejunum/ileum (villous height [VH], crypt depth [CD], and villous-to-crypt [V:C] ratio), and histological evaluation of several tissues from 432 day-old male broiler chickens divided into nine treatments according to the dose of FB (0, 100, or 200 mg/kg, from day 1 to day 28) and sLPS (0, 250, or 500 μg/application/bird, every other day, from day 15 do day 27). At the end of the experiment (28 d), significant effects of: sLPS were observed on BW, Ca, Col, Ph, UA, CRP, AST, AP, and VH; FB were observed on BW, FI, FCR, RWL, TPP, Alb, Ca, Tri, Col, UA, CRP, ALT, GGT, SA:SO, VH, and V:C; Interaction sLPS*FB were observed on RWL, Alb, Col, Ph, UA, and CRP. Histopathological evaluations showed significant lesions in liver and kidney caused by sLPS, FB and their association. According to these results, both sLPS and FB (isolated or associated) determine significant effects on performance and biological parameters of broilers at 28 days of age.
35

Desempenho, qualidade de ovos e metabolismo lipídico de poedeiras comerciais alimentadas com dietas contendo aflatoxina, fumonisina e adsorvente /

Siloto, Estela Valéria. January 2010 (has links)
Resumo: Os efeitos da aflatoxina e fumonisina e sua associação, sobre a produção e a qualidade dos ovos em poedeiras comerciais, foram avaliados bem como a eficácia de um adsorvente glucano em promover a redução e/ou eliminação total destes efeitos. Foram utilizadas 168 poedeiras com 37 semanas de idade, por um período experimental de 56 dias. O delineamento experimental foi inteiramente casualizado em esquema fatorial 3x2 + 1 (3 tratamentos com micotoxinas: aflatoxina (AF), fumonisina (FU) e aflatoxina + fumonisina (AF + FU); 2 tratamentos com e sem adsorvente; e grupo controle sem micotoxinas e adsorvente), totalizando 7 tratamentos e 6 repetições com 4 aves/gaiola. As rações foram contaminadas, isoladamente ou em combinação, com 1ppm de AF e 25ppm de FU e o adsorvente foi incluído na concentração de 2kg/ton ração. Os tratamentos com presença de AF apresentaram as menores porcentagens (p = 0,0594) de postura (76,72% para AF e 77,38% para AF+FU). A massa de ovos obteve a menor média (p<0,05) no tratamento com AF+FU (49,49 g) que foi diferente do grupo controle (64,06 g). O tratamento com AF apresentou maior espessura e resistência de casca comparado ao grupo controle e ao tratamento com FU. O uso do adsorvente no tratamento com AF reduziu a resistência da casca voltando aos valores próximos aos do controle. As alterações observadas neste estudo são indicativas da toxicidade da aflatoxina na concentração de 1 ppm. Os efeitos da fumonisina foram menos evidentes em função da baixa dose utilizada neste estudo (25mg/kg). O uso de glucano na concentração de 2 kg/ton foi efetivo em reverter alguns dos efeitos tóxicos da aflatoxina e, em menor extensão da fumonisina, quando estas micotoxinas estavam separadamente na ração de poedeiras comerciais / Abstract: The present study was conducted to evaluate the effects of aflatoxin and fumonisin and their association on production and egg quality in laying hens and was also evaluated the effectiveness of an adsorbent glucan to promote the reduction and/or total elimination of these effects. One hundred and sixty-eight 37-wk-old laying hens were used for a trial period of 56 days. The experimental design was a completely randomized with 3x2+ 1 factorial arrangement (three treatments with mycotoxins: aflatoxin (AF), fumonisin (FU) + fumonisin and aflatoxin (AF + FU), two treatments with and without adsorbent, and the control group without mycotoxin and adsorbent), totaling seven treatments, six replicates and four birds per cage. The mycotoxins were added to rations, singly and in combination, at levels of 1 ppm AF and 25 ppm FU and the adsorbent was included in the dosage of 2kg/ton .The treatments with the presence of AF had the lowest percentages (p = 0,0594) of stance (76,72% to AF and 77,38% to AF + FU). The egg mass received the lowest average (p<0,05) in the treatment with AF + FU (49,49 g) which was different from the control group (64,06 g). Treatment with AF showed higher values of thickness and peel strength compared to the control group and treatment with FU. The use of the adsorbent in the treatment with AF reduced the strength of the shell back to values near baseline. The changes observed in this study are indicative of the toxicity of aflatoxin at a concentration of 1mg/kg. The effects of fumonisin were less evident because of the low levels used in this study (25mg/kg). The level of glucan added to the diets was effective to prevent some of the toxic effects of aflatoxins and to a lesser extent of fumonisin, when the mycotoxins were separately in the diet of laying hens / Orientador: Denise Rangel da Silva Sartori / Coorientador: José Roberto Sartori / Banca: Alice Eiko Murakami / Banca: Daniela Felipe Pinheiro / Mestre
36

Interação entre Lipopolissacarídeo de Salmonella Typhimurium e Fumonisina B1 em frangos de corte

Rauber, Ricardo Hummes January 2012 (has links)
Lipopolissacarídeo (LPS) é o principal componente da parede celular de bactérias Gram-negativas, sendo liberado durante a divisão celular ou morte da bactéria após lise. O LPS é um dos mais potentes ativadores do sistema imune, desencadeando uma resposta inflamatória inespecífica. A exposição ao LPS tem sido associada a uma gama de efeitos tóxicos em frangos e outras aves, como hipertermia, inflamação, caquexia e, eventualmente, morte. A fumonisina B1 (FB), um metabólito secundário produzido pelo Fusarium verticilloides, tem sido descrita como causa de doenças previamente conhecidas (leucoencefalomalácea equina e edema pulmonar suíno), bem como causando alguns efeitos em aves. Os principais sinais clínicos da intoxicação por FB em frangos são desempenho reduzido, ascite, edema e congestão dos rins, diarreia, peso relativo do fígado aumentado e mortalidade. O objetivo deste trabalho foi avaliar os efeitos individuais e combinados do LPS de Salmonella Typhimuruim (sLPS) e FB sobre o desempenho produtivo (peso corporal [PC], consumo de ração [CR] e conversão alimentar [C]), peso relativo de fígado (PRF), parâmetros biológicos (proteínas plasmáticas totais [PPT], albumina [Alb], cálcio [Ca], triglicerídeos [Tri], colesterol total [Col], fósforo [P], ácido úrico [AU], proteína C-reativa [CRP], alanina aminotransferase [ALT], aspartato aminotransferase [AST], fosfatase alcalina [FA], gama glutamiltransferase [GGT] e relação esfinganina/esfingosina [SA:SO]), avaliação morfológica do intestino delgado (altura de vilosidades [AV], profundidade de criptas [PC] e relação vilosidade/cripta [V:C]) e avaliações histológicas de vários tecidos de 432 frangos de corte, machos, com um dia de idade, divididos em nove tratamentos, conforme a dose de FB (0, 100 ou 200 mg/kg, do primeiro ao 28º dia de experimento) e sLPS (0, 250 ou 500 μg/ave por aplicação, a cada 48 horas, do 15º ao 27º dia. Ao final do experimento (28 dias): efeitos significativos do sLPS foram observados sobre PC, Ca, Col, P, AU, CRP, AST, FA e AV; efeitos significativos da FB foram observados sobre PC, CR, C, PRF, PPT, Alb, Ca, Tri, Col, AU, CRP, ALT, GGT, SA:SO, AV e V:C; efeitos significativos da interação sLPS*FB foram observados sobre PRF, Alb, Col, P, AU e CRP. Alterações histológicas foram observadas para sLPS, FB e sLPS*FB no fígado e rins. De acordo com estes resultados, sLPS e FB (isolados ou associados) determinam efeitos sobre o desempenho e parâmetros biológicos de frangos de corte. / Lipopolysaccharide (LPS) is the main component of Gram-negative bacterial cell wall, and is released during cellular division or bacterial death after lysis. This is one of the most powerful activators of the immune system, leading to a non-specific inflammatory response. LPS exposure has been related to a role of effects in broilers and other avian species, such as hyperthermia, inflammation, cachexia, and eventually, death. Fumonisin B1 (FB), a secondary metabolite produced by Fusarium verticilloides, has been shown to be associated to some previously known diseases or syndromes (equine leucoencephalomalacea and porcine pulmonary edema) and has also been described as causing some effects in poultry. The main clinical signs of FB intoxication in broilers are reduced productive performance, ascites, kidney edema and congestion, diarrhea, increased relative weight of the liver, and mortality. The aim of this research was to evaluate the individual and combined effects of Salmonella Typhimurium Lipopolysaccharide (sLPS) and FB on performance (body weight, feed intake, and feed conversion rate), relative weight of the liver, biological parameters (total plasma proteins [TPP], albumin [Alb], calcium [Ca], triglycerides [Tri], total cholesterol [Col], phosphorus [Ph], uric acid [UA], C-reactive protein [CRP], alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [AP], gamma glutamiltransferase [GGT] and sphinganine-to-sphingosine [SA:SO] ratio), morphological evaluation of jejunum/ileum (villous height [VH], crypt depth [CD], and villous-to-crypt [V:C] ratio), and histological evaluation of several tissues from 432 day-old male broiler chickens divided into nine treatments according to the dose of FB (0, 100, or 200 mg/kg, from day 1 to day 28) and sLPS (0, 250, or 500 μg/application/bird, every other day, from day 15 do day 27). At the end of the experiment (28 d), significant effects of: sLPS were observed on BW, Ca, Col, Ph, UA, CRP, AST, AP, and VH; FB were observed on BW, FI, FCR, RWL, TPP, Alb, Ca, Tri, Col, UA, CRP, ALT, GGT, SA:SO, VH, and V:C; Interaction sLPS*FB were observed on RWL, Alb, Col, Ph, UA, and CRP. Histopathological evaluations showed significant lesions in liver and kidney caused by sLPS, FB and their association. According to these results, both sLPS and FB (isolated or associated) determine significant effects on performance and biological parameters of broilers at 28 days of age.
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Interação entre Lipopolissacarídeo de Salmonella Typhimurium e Fumonisina B1 em frangos de corte

Rauber, Ricardo Hummes January 2012 (has links)
Lipopolissacarídeo (LPS) é o principal componente da parede celular de bactérias Gram-negativas, sendo liberado durante a divisão celular ou morte da bactéria após lise. O LPS é um dos mais potentes ativadores do sistema imune, desencadeando uma resposta inflamatória inespecífica. A exposição ao LPS tem sido associada a uma gama de efeitos tóxicos em frangos e outras aves, como hipertermia, inflamação, caquexia e, eventualmente, morte. A fumonisina B1 (FB), um metabólito secundário produzido pelo Fusarium verticilloides, tem sido descrita como causa de doenças previamente conhecidas (leucoencefalomalácea equina e edema pulmonar suíno), bem como causando alguns efeitos em aves. Os principais sinais clínicos da intoxicação por FB em frangos são desempenho reduzido, ascite, edema e congestão dos rins, diarreia, peso relativo do fígado aumentado e mortalidade. O objetivo deste trabalho foi avaliar os efeitos individuais e combinados do LPS de Salmonella Typhimuruim (sLPS) e FB sobre o desempenho produtivo (peso corporal [PC], consumo de ração [CR] e conversão alimentar [C]), peso relativo de fígado (PRF), parâmetros biológicos (proteínas plasmáticas totais [PPT], albumina [Alb], cálcio [Ca], triglicerídeos [Tri], colesterol total [Col], fósforo [P], ácido úrico [AU], proteína C-reativa [CRP], alanina aminotransferase [ALT], aspartato aminotransferase [AST], fosfatase alcalina [FA], gama glutamiltransferase [GGT] e relação esfinganina/esfingosina [SA:SO]), avaliação morfológica do intestino delgado (altura de vilosidades [AV], profundidade de criptas [PC] e relação vilosidade/cripta [V:C]) e avaliações histológicas de vários tecidos de 432 frangos de corte, machos, com um dia de idade, divididos em nove tratamentos, conforme a dose de FB (0, 100 ou 200 mg/kg, do primeiro ao 28º dia de experimento) e sLPS (0, 250 ou 500 μg/ave por aplicação, a cada 48 horas, do 15º ao 27º dia. Ao final do experimento (28 dias): efeitos significativos do sLPS foram observados sobre PC, Ca, Col, P, AU, CRP, AST, FA e AV; efeitos significativos da FB foram observados sobre PC, CR, C, PRF, PPT, Alb, Ca, Tri, Col, AU, CRP, ALT, GGT, SA:SO, AV e V:C; efeitos significativos da interação sLPS*FB foram observados sobre PRF, Alb, Col, P, AU e CRP. Alterações histológicas foram observadas para sLPS, FB e sLPS*FB no fígado e rins. De acordo com estes resultados, sLPS e FB (isolados ou associados) determinam efeitos sobre o desempenho e parâmetros biológicos de frangos de corte. / Lipopolysaccharide (LPS) is the main component of Gram-negative bacterial cell wall, and is released during cellular division or bacterial death after lysis. This is one of the most powerful activators of the immune system, leading to a non-specific inflammatory response. LPS exposure has been related to a role of effects in broilers and other avian species, such as hyperthermia, inflammation, cachexia, and eventually, death. Fumonisin B1 (FB), a secondary metabolite produced by Fusarium verticilloides, has been shown to be associated to some previously known diseases or syndromes (equine leucoencephalomalacea and porcine pulmonary edema) and has also been described as causing some effects in poultry. The main clinical signs of FB intoxication in broilers are reduced productive performance, ascites, kidney edema and congestion, diarrhea, increased relative weight of the liver, and mortality. The aim of this research was to evaluate the individual and combined effects of Salmonella Typhimurium Lipopolysaccharide (sLPS) and FB on performance (body weight, feed intake, and feed conversion rate), relative weight of the liver, biological parameters (total plasma proteins [TPP], albumin [Alb], calcium [Ca], triglycerides [Tri], total cholesterol [Col], phosphorus [Ph], uric acid [UA], C-reactive protein [CRP], alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [AP], gamma glutamiltransferase [GGT] and sphinganine-to-sphingosine [SA:SO] ratio), morphological evaluation of jejunum/ileum (villous height [VH], crypt depth [CD], and villous-to-crypt [V:C] ratio), and histological evaluation of several tissues from 432 day-old male broiler chickens divided into nine treatments according to the dose of FB (0, 100, or 200 mg/kg, from day 1 to day 28) and sLPS (0, 250, or 500 μg/application/bird, every other day, from day 15 do day 27). At the end of the experiment (28 d), significant effects of: sLPS were observed on BW, Ca, Col, Ph, UA, CRP, AST, AP, and VH; FB were observed on BW, FI, FCR, RWL, TPP, Alb, Ca, Tri, Col, UA, CRP, ALT, GGT, SA:SO, VH, and V:C; Interaction sLPS*FB were observed on RWL, Alb, Col, Ph, UA, and CRP. Histopathological evaluations showed significant lesions in liver and kidney caused by sLPS, FB and their association. According to these results, both sLPS and FB (isolated or associated) determine significant effects on performance and biological parameters of broilers at 28 days of age.
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Efeitos do uso de adsorventes em frangos de corte alimentados com dietas naturalmente contaminados com aflatoxina e fumonisina

CALADO, Victor Hugo de Vasconcelos 11 March 2016 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-06-17T12:26:34Z No. of bitstreams: 1 Victor Hugo de Vasconcelos Calado.pdf: 593050 bytes, checksum: ab20bdddfa55a2c22cb9e115c16dbb93 (MD5) / Made available in DSpace on 2016-06-17T12:26:34Z (GMT). No. of bitstreams: 1 Victor Hugo de Vasconcelos Calado.pdf: 593050 bytes, checksum: ab20bdddfa55a2c22cb9e115c16dbb93 (MD5) Previous issue date: 2016-03-11 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Mycotoxins have been a problem in poultry production to be present in the major ingredients (corn and soybean meal) that make up the poultry feed, leading to problems such as an inadequate use of food and reduction of animal front immunity to various pathogens. Thus it aimed to evaluate the effects of adding mycotoxin adsorbents in broiler diets naturally contaminated with aflatoxin and fumonisin, on the parameters: histopathology, biometric and serological. The experiment was conducted with 60 birds, seven-day-old Cobb commercial line in three treatments: T1 - control (not including mycotoxin adsorbents in diet); T2 - adding 0.5 kg / t. of adsorbent A and T3 inclusion of 1.5 kg / t of adsorbent B. The broilers receive in all treatments, isonutritives diets naturally contaminated by mycotoxins. These broilers were raised up to 60 days old when was made serology tests for NDV and IBDV, and after were sacrificed for histopathologic and biometric analysis. The results were submitted to analysis of variance (ANOVA) with significance level of 5% probability and Tukey test. There were significant differences between treatments (P <0.05) in body weight. The body weight was significantly different between T1 and T2 (P = 0.01400), with a higher weight of the broilers receiving the adsorbent (4.26 ± 0.37). Among the organs analyzed, only the weight of the cecal tonsil significant difference between T1 and T2 (P <0.05; P = 0.03008), and T1 (5,20g ± 1.239) had an average weight slightly higher than average weight of T2 (4,05g ± 1.208). The amounts of immunoglobulins to IBDV showed significantly higher concentrations in T2 (P = 0.041). This contamination of broilers aflatoxin and fumonisin caused histopathological lesions in immune organs, liver and kidneys. However adsorbents used A and B reversed in parts of the lesions, especially in the liver, bursa and thymus. This reversal of lesions led to improved serological tests for IBD (Gumboro bursal-infectious disease) in the group treated with the adsorbent, resulting in broilers with better performance, suggesting that this adsorbent showed better effect on broilers in field conditions. / As micotoxinas têm sido um problema na produção avícola por estarem presentes nos principais ingredientes (milho e farelo de soja) que compõem a ração para aves, levando a problemas como: inadequado aproveitamento dos alimentos e diminuição de imunidade animal frente a patógenos diversos. Assim, objetivou-se avaliar os efeitos da adição de adsorventes de micotoxinas, em dietas de frangos de corte contaminadas naturalmente com aflatoxinas e fumonisinas, sobre os parâmetros: biométricos, sorológicos e histopatológicos. O experimento foi realizado com 60 aves, com sete dias de idade, da linhagem comercial Cobb distribuídas em três tratamentos: T1 – Controle (sem inclusão de adsorventes de micotoxinas na dieta); T2 – inclusão de 0,5 kg/t do adsorvente A (composto por aluminossilicato de sódio e cálcio modificado industrialmente) e T3- inclusão de 1,5 kg/t do adsorvente B(composto por aluminossilicato de sódio e cálcio). As aves receberam, em todos os tratamentos, dietas isonutritivas, feitas com milho sabidamente contaminado, em campo por micotoxinas. Essas aves foram criadas até 60 dias de idade, quando foi realizada sorologia para NDV(vírus da doença de Newcastle) e IBDV(vírus da doença infecciosa bursal) e preparadas para eutanásia para posteriores análises histopatológicas e biométricas. Ao final, o peso vivo foi significativamente diferente entre os tratamentos T1 e T2 (P=0,01400), observando-se maior peso das aves que receberam o adsorvente A (4,26 ± 0,37). Entre os órgãos analisados, apenas o peso da tonsila cecal apresentou diferença significativa entre os tratamentos T1 e T2 (P<0,05; P=0,03008), sendo que T1 (5,20g ± 1,239) apresentou peso médio levemente superior ao peso médio do T2 (4,05g ± 1,208). No teste sorológico, as quantidades de imunoglobulinas para IBDV apresentaram concentrações significativamente maiores no T2 (P=0,041). A intoxicação das aves com aflatoxinas e fumonisinas provocou lesões histopatológicas nos órgãos linfóides (bolsa cloacal, baço, timo e tonsilas cecais), fígado e rins. Contudo os adsorventes usados A e B minimizou as lesões, principalmente no fígado, bursa, e timo. A menor intensidade das lesões proporcionou melhores resultados sorológicos para IBDV no grupo tratado com o adsorvente A, resultando em aves com melhor desempenho, conclui-se sugerindo que este adsorvente produz melhor efeito nas aves em condições de campo.
39

Investigations on the antifungal and cancer modulating properties of extracts from selected species of Tulbaghia

Keyser, Zanephyn January 2012 (has links)
Philosophiae Doctor - PhD / Fusarium verticil/ioides (Sacc) Nirenberg a common phytopathogen of maize and maize-based products produces fumonisin B (FB) mycotoxins that have been related to several diseases such as equine leukoencephalomalacia (ELEM), porcine pulmonary edema (PPE), liver toxicity in several animals and esophageal and liver cancer in humans. In one of our studies we hypothesize that aqueous extracts of indigenous South African wild garlic species (Tulbaghia violacea, T. alliacea and T. simmleri) may enhance the efficacy of the fungicides, SporekilPu, Thiram, Itraconazole and Fluconazole against F. verticil/ioides (MRC 826). Data analysis from in vitro results indicates that for the 16 different mixtures of each plant extract and fungicide combination, several significantly (P<O.05) higher growth inhibition responses were produced. More synergistic interactions were observed for the combinations of sporekill with T. violacea (62%) and T. alliacea (75%) than for T. simmleri (25%) .. Mixtures between the azole fungicides and T. simmleri produced 94 % synergistic interactions. Combination of fungicides and plant compounds offers the opportunity to find synergistic mixtures and may validate disease control strategies with increased biological activity and low dose rate application. Modulation studies of hepatic drug metabolizing enzymes and oxidative properties of AI/ium sativum, Tulbaghia violacea and T. alliacea in male Fischer rats were also evaluated. Due to its complex phytochemical composition a battery of assays were used to evaluate antioxidant potential. The extracts exhibited no adverse effects in the liver and kidneys of the rats. Total plasma iron was not affected showing no evidence for iron catalyzed lipid peroxidation. An increase was noted in hepatic ORAC values for rats consuming T. violacea and T. al/iacea. However, no correlation was observed between the phenolic intake by the rats and the increased hepatic ORAC levels. In this study, pre-treatment with aqueous extracts of T. violacea, T. al/iacea and A. sativum resulted in a significant elevation in GSH levels, induction of GST -IJ and UDP-GT and modulation of CAT and SOD. This modulated oxidative status and phase II drug metabolizing enzymes in the liver may protect the liver against the adverse effects related to oxidative damage and mutagenesis. The chemoprotective properties of crude aqueous extracts of A. sativum, T. violacea and T. alliacea were investigated on preneoplastic foci formation promoted by culture material of F. verticil/ioides MRC 826 utilizing diethylnitrosamine (DEN) as cancer initiator. Clinical chemical parameters related to liver and kidney function and decreased body weight gain suggesting that severe, acute liver injury had been induced in the positive control (DEN-eMF) rats, while the levels were mostly reduced by the garlic treatments. This study further indicates that T. alliaceae (2 % w/v) and A. sativum (1% w/v) treatment suppressed GST-P+ foci formation with the modulation of GST-0 phase II detoxification enzymes, as well as the antioxidant enzyme, SOD (T. alliaceae) and decreased GSH levels as being possible mechanisms of protection. These results provide new evidence showing the modulation of phase II drug metabolizing enzymes and the oxidative status in the liver of rats by the wild garlic species as well as A. sativum.
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A Comprehensive Comparison of Teratogenic Compounds Known to Induce Neural Tube Defects in the Chicken Embryo

Ross, Micah Marie 31 July 2020 (has links)
One of the first embryonic structures generated during early human development is the neural tube. The embryonic process of neurulation, including neural tube closure, is necessary for proper brain and spinal cord development, whereas improper closure leads to neural tube defects including anencephaly, spina bifida, and craniorachischisis. The mechanism by which these defects occur is unknown, but some evidence suggest that redox disruption may play a role. Cellular redox state is important in regulating key processes during neural tube closure, including differentiation, proliferation, gene expression, and apoptosis. This study aims to determine whether redox potential shifts and these key processes are affected similarly or differentially after treatment with three neural tube defect-inducing developmental toxicants: ceramide (C2), valproic acid (VPA), and fumonisin (FB1). Using the P19 cell model of neurogenesis, in both undifferentiated and terminally differentiated cells, we analyzed glutathione (GSH) redox (Eh) potential to evaluate the effect of each toxicant over time. We show that in C2 and VPA treated cultures an oxidizing shift occurs, but interestingly, FB1 treatment results in a reducing shift in embryonic GSH Eh as compared to untreated cultures. Using the chick embryo model, comparable redox shifts were observed as were seen in P19 cells, supporting similarity between the models. To better understand how differential shifts in the redox state can result in similar defects, we then examined potential variances in neuronal differentiation and cellular proliferation, survival, metabolism, adhesion, and gene expression under each treatment. We report changes to cellular and embryonic endpoints that support dysmorphogenesis, likely the result of oxidizing or reducing stress that altered redox state. These results support the need for broad comparative analyses such as this to determine whether toxicants that cause the same types of defects, whether NTDs or others, act through similar or different mechanisms. This can better inform preventative measures used to reduce the risk and occurrence of birth defects.

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