Foram conduzidos três experimentos com os objetivos de avaliar a influência da glutamina e nucleotídeos nas dietas de frangos de corte, considerando o desempenho, desenvolvimento e atividade enzimática da mucosa intestinal. No 1º experimento, foi determinado os melhores níveis de suplementação das fontes de glutamina, isolado (L-Gln) ou associado com ácido glutâmico (Aminogut®), e de acordo com resultados obtidos para as características de desempenho e atividades enzimáticas (mucosa intestinal e pâncreas), observou-se melhor desempenho para aves suplementadas com 1,5% de L-Gln e 3,0% de Aminogut®. No 2º experimento, foi determinado o melhor período (1 a 7, 1 a 14 ou 1 a 21 dias de idade) de suplementação dos níveis ótimos das fontes de glutamina observados no experimento 1. Segundo dados de desempenho, atividades enzimáticas e morfometria do intestino delgado (duodeno, jejuno e íleo), determinou-se que as fontes de glutamina podem ser suplementadas durante os primeiros sete dias de vida das aves, proporcionando aumento nas atividades das enzimas digestivas e pancreáticas nos frangos. No 3º experimento, foram avaliados os efeitos de três fontes de ação trófica (L-Gln, Aminogut® e nucleotídeos) associadas à vacinação contra a coccidiose, sobre o desenvolvimento do intestino delgado e algumas respostas imunológicas das aves. Pode ser observado efeito negativo da vacinação sobre o desempenho e morfometria da mucosa intestinal, entretanto, ao final do período experimental, as fontes de glutamina mostraram-se eficiente em recuperar perdas epiteliais da mucosa intestinal das aves desafiadas contra a coccidiose. Portanto, a suplementação destas fontes de ação trófica pode ser uma estratégia para o bom desenvolvimento dos frangos quando submetidos à estresse vacinal, considerando ainda a viabilidade econômica pelo segmento produtivo. / Three experiments were carried out to evaluate the influence of glutamine and nucleotides in diets of broiler chickens, on performance, development and enzymatic activity of the intestinal mucosa. In the first experiment, was estimated the best levels of glutamine sources supplementation, isolated (L-Gln) or associated with glutamic acid (Aminogut®). According to results for performance characteristics and enzymatics activities (intestinal mucosa and pancreas), was observed best performance for birds supplemented with 1.5% of L-Gln and 3.0% of Aminogut®. In the second experiment, was determined the best supplementation period (1 to 7; 1 to 14 or 1 to 21 days of age) of levels of glutamine sources observed in the first experiment. The results of performance, enzymatics activities and small intestine morphometry (duodenum, jejunum and ileum), suggested that glutamine sources evaluated can be supplemented during the first seven days of age, providing an increase in the enzymatics digestives and pancreatic activities at the broiler chickens. In the third experiment, were evaluated the effects of three sources with action trophic (L-Gln, Aminogut® and nucleotides) associated with vaccination against coccidiosis on development of small intestine and immune responses of the broilers. It was observed negative effect of vaccination on performance and morphometry of intestinal mucosa, however, at the end of experimental period, the glutamine sources showed efficiency to recovery epithelial losses of intestinal mucosa of birds, which were challenged against coccidiosis. Therefore, the supplementation of the trophic sources can be a strategy for optimum development of broilers when submitted to vaccination stress, considering the economic viability by the productive segment.

Um experimento foi realizado com o objetivo de avaliar diferentes alternativas nutricionais no controle de diarréia de leitões. Foram utilizados 128 leitões de uma linhagem comercial, desmamados com idade média de 21 dias, sendo metade de cada sexo. Os leitões foram distribuídos em 32 baias, sendo cada unidade experimental composta por quatro leitões. O delineamento experimental foi o de blocos ao acaso, com os animais distribuídos em oito tratamentos e quatro repetições de quatro animais (dois machos e duas fêmeas). Tratamentos: T1 - alto calcário, sem óxido de zinco, sem ácido benzóico; T2 - alto calcário, com óxido zinco, sem ácido benzóico; T3 - baixo calcário, sem óxido de zinco, sem ácido benzóico; T4 - baixo calcário, com óxido zinco, sem ácido benzóico; T5 - alto calcário, sem óxido zinco, com ácido benzóico; T6 - alto calcário, com óxido de zinco, com ácido benzóico; T7 - baixo calcário, sem óxido de zinco, com ácido benzóico; T8 - baixo calcário, com óxido de zinco, com ácido benzóico. As dietas foram fornecidas em dois períodos: de 1 a 14 dias pós-desmame (Fase I) e de 15 a 28 dias pós-desmame (Fase II). A partir do 29º dia os animais receberam uma mesma dieta até os 70 dias de idade. As características zootécnicas avaliadas foram: o ganho de peso, o consumo de ração, índice de conversão alimentar e a incidência de diarréia. Além disso, foram avaliadas a altura das vilosidades do duodeno, a profundidade das criptas e a relação altura de vilosidades/profundidade de cripta. Ao final do experimento, foi coletada a tíbia para a avaliação da densidade óssea. O óxido de zinco diminuiu a incidência de diarréia e foi mais eficiente em melhorar o GPMD e o CRMD de 1 a 14 dias pós-desmame. O ácido benzóico associado ao baixo calcário melhorou o GPMD de 15 a 28 dias pós-desmame e teve efeito positivo na morfologia duodenal. A diminuição do nível de calcário não prejudicou a densidade mineral óssea dos animais. / One trial was conducted to evaluate different nutritional alternatives for diarrhea control in weanling piglets. One hundred twenty eight piglets (half male and half female) were weaned with approximately 21 days of age. The piglets were distributed in 32 pens and each one was an experimental unit with four piglets. In a block design, the animals were distributed in eight treatments and four replications with four animals each (two male and two female). Treatments: T1 - high limestone, without zinc oxide and benzoic acid; T2 - high limestone, with zinc oxide and without benzoic acid; T3 - low limestone, without zinc oxide and benzoic acid; T4 - low limestone, with zinc oxide and without benzoic acid; T5 - high limestone, without zinc oxide and with benzoic acid; T6 - high limestone, with zinc oxide and benzoic acid; T7 - low limestone, without zinc oxide and with benzoic acid; T8 - low limestone, with zinc oxide and benzoic acid. The diets were given in two periods: d 1 - 14 postweaning (Phase I) and d 15 - 28 postweaning (Phase II). The animals were fed with common diet from d 29 until 70 days of age. Parameters evaluated were: body weight gain, fed conversion, and diarrhea incidence. In addition, duodenum\'s villus height, crypt depth, and villus height/crypt depth were evaluated. At the end of time trial, tibia was collected for bone density analyze. Zinc oxide reduced diarrhea incidence and improved GDW and DC from d 1 - 14 postweaning. Benzoic acid with low limestone level improved GDW from d 15 - 28 postweaning and duodenal morphology was affected positively. The lower level of limestone did not affect mineral bone density of the animals.

Aim. Baicalein is a bioactive flavonoid component isolated from the root of Scutellaria baicalensis, which has been used as a traditional Chinese medicinal herb for the treatment of inflammation for centuries. Although various pharmacological effects of baicalein have been demonstrated, only limited studies in rats reported pharmacokinetic of baicalein, which exhibited a low oral bioavailability due to extensive first-pass metabolism. In addition, no investigation on human oral absorption or metabolic kinetic profile was reported previously. The current project conducted a series of mechanistic studies aiming to elucidate the intestinal absorption, metabolism and disposition of baicalein. Since glucuronidation plays an important role in the first-pass metabolism of flavonoids including baicalein, additional studies on the relationship between human intestinal glucuronidation activities and chemical structures of flavonoids have also been performed. / Conclusion. Baicalein is well absorbed at intestine but subjected to extensive intestinal glucuronidation resulting in low oral bioavailability. The glucuronidation of baicalein is catalyzed by multiple UGT isozymes. The disposition of baicalein 7-O-glucuronide, the major metabolite of baicalein in vivo, is mediated by the MRP and OATP transporters. The nucleophilicity and stereo-conformation of -OH substituents are crucial for the intestinal glucuronidation of flavonoids. / Methods. For investigation on intestinal absorption, metabolism and disposition of baicalein, human Caco-2 cell monolayer model, rat in situ intestinal perfusion model, and in vitro metabolism model were employed in the present study. For the further investigation on the position preference on glucuronidation of flavonoids at human intestine, the in vitro rates of glucuronidation among seven commercially available mono-hydroxyflavones, namely 3-, 5-, 6-, 7-, 2'-, 3'- and 4'-mono-hydroxyflavones were determined and compared. / Results. The satisfactory permeabilities of baicalein obtained from both Caco-2 cell model and rat intestinal perfusion model indicated its potential good absorption at gastrointestinal tract. Therefore, absorption should not be the rate-limiting factor causing the low oral bioavailability of baicalein. However, extensive glucuronidation occurred in the rat intestine perfusion model with over 90% of baicalein being metabolized after intestinal absorption. Consistent findings were also observed in the in vitro enzyme kinetic studies of baicalein. The biotransformation of baicalein to baicalein 7-O-glucuronide was extensive in human liver microsome, human jejunum microsome, rat liver microsome, and rat jejunum microsome with intrinsic clearances (Vmax/Km) of 618, 446, 436, 298 mul/min/mg, respectively, which are orders of magnitude greater than those of most of western drugs that share the same metabolic pathway. Further enzyme kinetic studies using human recombinant glucuronosyltransferases (UGT) isozymes showed that UGT 1A1, 1A3, 1A8, 1A9, 1A7 and 2B15 were involved in the glucuronidation of baicalein with different kinetic profiles. Mechanistic studies on the disposition of baicalein 7-O-glucuronide formed from a rapid glucuronidation of baicalein in intestine demonstrated that this intracellularly formed glucuronide of baicalein could be actively extruded to both the apical and basolateral sides (the so called efflux) in Caco-2 cell model as well as rat intestinal perfusion model. It was also found that the efflux of the baicalein 7-O-glucuronide followed saturable enzyme kinetics and was effectively inhibited by multi-drug resistance associated proteins (MRP) and organic anion transporters (OATP) inhibitors. Further study on the relationship between flavonoid structures and glucuronidation activities using seven monohydroxyflavones demonstrated that the conjugation rates of 6- and 3'-monohydroxyflavones (HF) were much greater than those of 3-, 4'-, 7-, 2'-HF, while 5HF was the lowest. / Zhang Li. / "August 2006." / Advisers: Zhong Joan Zuo; Ge Lin. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1587. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 186-223). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Le vieillissement est un processus physiologique au cours duquel l’ensemble de l’organisme voit son fonctionnement modifié. Il s’agit d’un remodelage génotypique et phénotypique, en lien avec le stress oxydatif. Les molécules antioxydantes comme les composés phénoliques (CP) ont pris une place importante dans la diète humaine, à titre de compléments alimentaires et/ou à titre thérapeutique. Toutefois, les conséquences d’un usage à long terme de ces molécules visant à reverser les effets du vieillissement sur les fonctions organiques, restent encore mal élucidées. Dans ce contexte, et compte tenu de notre intérêt pour le cœur, le rein et le microbiote intestinal, l’objectif de cette thèse est d’évaluer, sur de jeunes rats mâles, les effets des CP administrés à différentes concentrations, pendant quatorze mois. Les groupes traités par les CP ont montré une préservation, avec l’âge, de la performance cardiaque par rapport aux témoins non traités. De plus, les myocardes de rats âgés traités ont présenté de moindres signes d’inflammation, de fibrose et d’apoptose que les témoins. Ces modifications sont soutenues par un remodelage du niveau d’expression protéique des marqueurs de l’hypertrophie et du stress oxydatif, et des résultats préliminaires suggèrent une activation du courant potassique KATP en présence des CP sur les myofibroblastes. Le tissu rénal conserve son architecture normale avec l’âge chez tous les groupes. Enfin, les métabolites issus des CP ont montré une modulation sélective du microbiote intestinal vers un phénotype sain. Nos travaux montrent dans un modèle murin qu’une consommation régulière de CP permet de préserver le cœur, les reins et le microbiote du remodelage lié au vieillissement. / Aging is a physiological process in which the entire body sees its normal functional capacities modified. It is associated with a genotypic and phenotypic remodeling, related to oxidative stress. Antioxidant molecules such as phenolic compounds (PC), have taken an important place in the human diet, as food supplements and/or as therapeutics. However, the consequences of long-term use of these molecules to reverse the effects of aging on organic functions, remain poorly understood. In this context, and considering our interest for the heart, the kidney and the intestinal microbiota, the aim of this thesis is to evaluate, in young male rats, the effects of PC administered at different concentrations for a period of fourteen months. PC treated groups showed a dose-dependent preservation of cardiac morphology and performance compared to control untreated ones. Additionally, myocardia from treated aged rats exhibited less inflammation, fibrosis and cardiomyocyte apoptosis than controls. These modifications were supported by a remodeling of the proteins level expression of the markers of hypertrophy and oxidative stress, and preliminary data suggest a concomitant activation of potassium current KATP on myofibroblasts in the presence of PC. Renal tissues retained their normal architecture with age in all groups. Finally, derived-metabolites from PC showed a selective modulation of intestinal microbiota towards a healthy phenotype. Our work shows that regular consumption of PC may preserve the heart, kidneys and microbiota of age-related remodeling.

Objetivos: O presente trabalho é secundário a um estudo clínico randomizado, que teve por objetivos investigar os efeitos de uma substância simbiótica sobre a permeabilidade intestinal, a inflamação sistêmica, a cognição e sintomas depressivos em idosos. Métodos: quarenta e nove participantes, 65-90 anos de idade, ambos os gêneros, foram randomizados em dois grupos: grupo S (uso de simbióticos); e grupo P (uso de placebo). As seguintes avaliações foram realizadas no início e no final do experimento: Escala de Depressão Geriátrica (GDS-15); Mini Exame do Estado Mental (MEEM); % de gordura corporal (%gordura); citocinas pró-inflamatórias e regulatórias no soro (IL-6, TNF-α e IL-10); e marcadores de permeabilidade intestinal no soro (DAO, IFABP e LPS). Resultados: A interação entre tempo e grupo mostrou maior redução do LPS no grupo P e maior aumento do IL-10 no grupo S. Considerando somente o fator tempo, ambos os grupos reduziram a %gordura, TNF-α e DAO. O IL-6, o GDS-15 e MEEM aumentaram em ambos os grupos. O valor final de GDS-15 foi explicado negativamente por DAO, IL-10, TNF-α, %gordura, ser mulher e estar alocado no grupo P. As variáveis que explicaram positivamente o valor final do GDS-15 foram IL-6, IFABP, e LPS. As variáveis positivamente associadas aos valores finais do MEEM foram IL-10, DAO, ser mulher e estar alocado no grupo P; foram encontradas associações negativas entre o MEEM e IL-6, TNF-α, %gordura, IFABP e LPS. Foi discutida a possibilidade de alguma interferência dos medicamentos utilizados pelos idosos, nas variáveis de interesse do estudo. Conclusões: de acordo com nossas condições experimentais, foram encontrados efeitos sutis da suplementação de simbióticos sobre sintomas depressivos e cognição em idosos da comunidade, aparentemente saudáveis; entretanto, os efeitos sobre a cognição parecem ter sido mais otimistas. Estudos futuros, com indivíduos com diagnóstico de depressão ou de comprometimento cognitivo, poderão clarear questões levantadas no presente estudo. / Objectives: This secondary study from a randomized clinical trial aimed to investigate the effect of a synbiotic substance on intestinal permeability, systemic inflammation, cognition and depressive symptoms in elderly. Methods: Forty-nine participants, 65-90 years old, both genders, were randomly assigned into two groups: S-group (synbiotic); and P-group (placebo). Evaluations performed at the beginning and at the end of the experiment were: Geriatric Depressive Symptoms scale (GDS-15); Mini-Mental Status Examination (MMSE); % of body fat (%fat); pro-inflammatory and regulatory cytokines (serum IL-6, TNF-α and IL-10); gut permeability (serum DAO, IFABP and LPS). Results: The interaction between time and group showed higher reduction of LPS in P-group and higher increase of IL-10 in S-group. Considering only time, both groups had reduced their %Fat, TNF-α and DAO. The IL-6, GDS-15 and MMSE were increased in both groups. The GDS-15 final was negatively explained by DAO, IL-10, TNF-α, %Fat, being woman and being allocated in P-group. The variables that positively explained the GDS-15final were the IL-6, the IFABP, and the LPS. The variables that were positively associated to MMSE final were the IL-10, DAO, being woman, and being allocated in P-group; The negative associations were IL-6, TNF-α, %Fat, IFABP and LPS. We discussed the possibility of some interference of the medicines used by the elderly on our outcomes of interest. Conclusions: our experimental conditions demonstrated weak effects of synbiotic supplementation in the management of depressive symptoms or cognitive decline in apparently healthy elderly living in the community, although the effect on cognition seems to be more optimist. Other comparative studies, with individuals diagnosed as depressive morbidity or cognitive decline, may clarify our hypothesis.

La consommation excessive d’alcool est la première cause de cirrhose en France. L’atteinte hépatique débute par une stéatose (accumulation de triglycérides dans les hépatocytes) qui peut évoluer vers un état inflammatoire (hépatite alcoolique) lors d’une consommation chronique d’alcool. La maladie peut ensuite évoluer vers la fibrose, la cirrhose et jusqu'à l’hépatocarcinome. La mortalité des formes aiguës de l’hépatite alcoolique sévère est comprise entre 50 et 75%. La corticothérapie est le seul traitement qui peut améliorer le pronostic à court terme. D’autres facteurs que la seule consommation excessive d’alcool interviennent dans la genèse des lésions hépatiques. Ainsi, parmi les sujets ayant une forte consommation d’alcool à long terme, la majorité des patients développent une stéatose mais seulement 10 à 35% développeront une hépatite et 8 à 20% évolueront vers la cirrhose. La recherche de facteurs qui relient la consommation d’alcool et la nature et progression des lésions hépatiques est donc essentielle pour trouver de nouvelles cibles thérapeutiques améliorant la prise en charge de ces formes graves. Afin de rechercher quels sont ces facteurs, nous avons utilisé un modèle murin d’alcoolisation. Nous avons utilisé un régime Lieber de Carli (LDC) enrichi en graisses, additionné d’alcool ou non. Nous avons orienté notre projet vers un axe microbiote-inflammation hépatique en analysant l’évolution des populations bactériennes intestinales au cours de la surconsommation d’alcool chez la souris. Des résultats nous ont montré que les Bacteroides variaient grandement d’une animalerie à l’autre. L’objet de nos travaux était d’étudier l’effet de la modulation des Bacteroides sur l’apparition des lésions hépatiques lors de la maladie alcoolique du foie. / Excessive alcohol consumption in the first cause of liver cirrhosis in France. Liver damages begin with steatosis (accumulation of fat in hepatocytes), which can progress to an inflammatory state (alcoholic hepatitis) during a long-term chronic alcohol consumption. Then, the disease can degenerate in liver fibrosis, cirrhosis and reach the hepatocarcinoma state. The mortality rate of acute alcoholic hepatitis ranges from 50% to 75%. Treatment based on corticoids is the only available and efficient treatment to improve the short-term prognosis. Other factors than only excessive alcohol consumption play a role in the onset of hepatic damages. Among patients having a long-term alcohol excessive consumption, most of them will develop a steatosis, whereas only 10% to 35% will develop alcoholic hepatitis and only 8 to 20% a liver cirrhosis. Researching these factors linking alcohol consumption and the nature and onset of liver injuries is of the utmost importance in order to find new therapeutic targets improving the patient life expectancy.In order to research these actors, we used a mice alcoholization model. We used a Lieber DeCarli diet, enriched in fat, added with ethanol or not. We studied the link between intestinal microbiota composition and the onset of liver injuries, by analyzing bacterial populations during an excessive alcohol consumption in mice. We discovered that one of the major bacterial population composing the intestinal microbiota, Bacteroides, underwent differential modifications from one animal housing facility to the other. The aim of our work was to modulate the Bacteroides population and study its effects on liver injuries.

Orientador: Pedro Luiz Toledo de Arruda Lourenção / Resumo: Introdução: A constipação intestinal é uma condição debilitante que afeta mais de 27% da população, representando um problema de saúde pública, além de corresponder a 3% de todas as consultas pediátricas. Existem várias causas congênitas e adquiridas. A Doença de Hirschsprung (DH) é a principal causa congênita de constipação e envolve 90% dos casos congênitos. O diagnóstico de disganglionoses intestinais depende da análise histopatológica de biópsias retais. Nessa revisão sistemática, levantamos todas as series de casos disponíveis na literatura e desenvolvemos uma metanálise de proporções para definer a taxa de resultados conclusivos e as complicações relacionadas aos diferentes tipos de biópsia retal no diagnóstico de disganglionoses intestinais. Métodos: A partir de ampla busca na literatura em múltiplas bases de dados, foi realizada uma revisão sistemática e metanálise de proporção das séries de casos que envolviam biópsias retais em pesquisa de disganglionoses intestinais em crianças. Foram incluídas series de casos que envolvessem mais de 5 biópsias em pacientes menores de 18 anos de idade com suspeita de disganglionose intestinal, que descrevesse ao menos um tipo de biópsia retal. Os estudos deviam especificar a taxa de resultados conclusivos e a taxa de complicações das técnicas de biópsias. A análise de proporção de série de casos foi realizada e os resultados apresentados em gráficos do tipo forest plot. Resultados: Foram selecionados 151 estudos pelos critérios de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction: Intestinal constipation is a debilitating condition that affects up to 27% of the population, representing an important public health problem and corresponding to 3% of all pediatric consultations. There are many different congenital and acquired conditions, but Hirschsprung’s disease (HD) is the main representative entity of congenital disease and is involved in 90% of all cases. The diagnosis of intestinal dysganglionosis depends on the histopathological analysis of rectal biopsies. Here we conducted an updated systematic review of all case series studies available in the literature and performed a pooled analysis of proportions to assess the rate of conclusive results and possible complications of different rectal biopsy techniques in the diagnosis of intestinal dysganglionosis. Methods: A broad literature search using multiple online databases. A systematic literature review and proportional meta-analysis of the available case series studies of rectal biopsies in the diagnosis of intestinal dysganglionosis in children were performed. We included case series with more than 5 rectal biopsies in children under 18 years of age suspected of intestinal dysganglionosis, that described at least one type of rectal biopsy. The studies should have specified the rate of conclusive results and the rate of complications of the biopsy procedures. Proportional meta-analysis of case series studies was performed and forest plot charts were created to summarize the data. Resul... (Complete abstract click electronic access below) / Doutor

Em nosso estudo pretendemos estudar a via oral para o desenvolvimento de vacina para toxoplasmose utilizando parasitas irradiados por Cobalto-60, como uma alternativa para a prevenção desta importane parasitose. Para tanto, avaliamos o desenvolvimento da imunidade sistêmica e intestinal e a resistência à infecção, em camundongos imunizados por esta via com taquizoítos irradiados a 255Gy, e desafiados com cistos da cepa ME-49. Camundongos isogênicos C57Bl/6j foram imunizados com 107 taquizoitos de T. gondii irradiados a 255Gy em diferentes esquemas e utilizando adjuvantes leite (anti-péptico) e hidróxido de alumínio (anti-ácido). As preparações de taquizoítos irradiados por via oral induziram produção de imunoglobulinas IgG e IgA no soro de camundongos, sendo predominante a subclasse de IgG2a, similar a infecção crônica, determinadas por ELISA. Seu uso com adjuvantes anti-pépticos ou anti-ácidos induziu produção de IgA fecal e menos significativamente de IgG fecal. Existem indícios de indução de tolerância em nível intestinal, com queda da produção de anticorpos e da proliferação celular antígeno dirigida, especialmente quando o leite foi utilizado como adjuvante, em ensaios de produção in vitro de anticorpos ou proliferação estimulada por antígenos de T.gondii, por esplenócitos e linfócitos intestinais. As preparações orais induziram proteção quantitativa ao desafio dos animais imunizados por cepa cistogênica, que foi semelhante a imunização parenteral, quando o hidróxido de alumínio foi usado como adjuvante. Todos estes dados mostram a possibilidade de desenvolvimento de uma vacina oral para toxoplasmose utilizando taquizoítos irradiados, com aplicação prática num futuro próximo para uso em campo, utilizando iscas atrativas para imunizar felinos domésticos e selvagens. / We study the oral route for the development of a vaccine for toxoplasmosis, using parasites irradiated with 60 Cobalt, as an alternative for vaccine development to this worldwide parasitic infection. We evaluated the development of immunity at serum or mucosal levels, and their efficiency in protect the mice against challenge with oral cysts of the ME-49 strain. C57Bl/6j isogenic mice were immunized by oral route with 107 255 Gy irradiated tachyzoites from RH strain, at several protocols using milk as anti-peptic adjuvant and alum hydroxide as antacid. The preparations of irradiated tachyzoites induced production of serum IgG and IgA in immunized mice, as determined by ELISA, with IgG2a as the dominant subclass, similar to chronic infection. Their use with adjuvant allowed the excretion of significant amounts of IgA in stools also IgG, despite a lesser extent. There are suggestion of tolerance induction at mucosal level, with lower antigen induced proliferation and lower in vitro antibody production by spleen and gut lymphocytes, with the latter doses, specially when milk was used as adjuvant. All oral preparations induced some quantitative protection against challenge, which was similar to the parenteral route only isolated alum hydroxide was used as adjuvant. All these data support the possibility of the development of an oral vaccine against toxoplasmosis, using irradiated tachyzoites, which would be possible tool in near future for use in field baits, for immunizing either domestic or wild felids.

Este estudo teve o objetivo de avaliar a eficiência do probiótico em manter o equilíbrio da microbiota intestinal de aves submetidas à antibioticoterapia e as associações com o desempenho. Os tratamentos dietéticos consistiram de uma dieta basal única, à base de milho e farelo de soja, à qual foi acrescido ou não o probiótico Bacillus subtillis (100 g/ton de ração), na concentração de 10? UFC/g. Por 3 dias consecutivos a partir de 21 dias de idade, as aves foram submetidas à antibioticoterapia via água de bebida consistindo de 200 ppm de bacitracina metileno dissacilato (efeito em bactérias Gram-positivas ) e 1000 ppm de sulfato de neomicina (efeito em bactérias Gram-negativas). O experimento foi conduzido com frangos de corte no período de 1 a 42 dias, sendo que de 1 a 21 dias as aves receberam somente o tratamento dietético, e, a partir de 21 dias, as aves receberam os tratamentos dietético e terapêutico. Aos 2, 4 e 6 dias após a antibioticoterapia, 3 aves de cada unidade experimental foram sacrificadas para coleta do conteúdo do intestino delgado e do ceco e obtidos \"pools\" dos conteúdos intestinais em cada unidade experimental para constituir uma repetição. O experimento foi realizado com 4 tratamentos, obedecendo a esquema fatorial 2×2 para as variáveis de desempenho (com e sem probiótico × com e sem antibioticoterapia) com 9 repetições e 2×2×3 para as análises da microbiota intestinal (com e sem probiótico na dieta × com e sem antibioticoterapia × 2, 4 e 6 dias após a antibioticoterapia) com 3 repetições. O DNA total foi extraído dos conteúdos do intestino delgado e ceco para o isolamento da região 16S rRNA e análise das comunidades bacterianas. As técnicas moleculares utilizadas foram a de fingerprinting Terminal Restriction Length Polymorphism (T-RFLP), PCR em tempo real (qPCR) e o sequenciamento, sendo que, para todas as técnicas, a região alvo foi o gene 16S rRNA. Os fatores dietético e terapêutico modularam a microbiota intestinal de forma independente. Houve efeito dos fatores probiótico e antibioticoterapia nos grupos predominantes do conteúdo do intestino, desde a classificação taxonômica filo até a classificação gênero. Alguns grupos filogenéticos foram igualmente afetados pelos 2 fatores em estudo, enquanto que outros grupos foram alterados de forma específica em função do probiótico ou antibioticoterapia. A antibioticoterapia, assim como o probiótico dietético, reduziu o número de unidades taxonômicas operacionais (OTUs) no conteúdo do ceco. O melhor desempenho observado nas aves alimentadas com dietas com probiótico provavelmente está relacionado às alterações observadas na estrutura das comunidades intestinais e grupos filogenéticos, como o acréscimo de Lactobacillus e redução de Clostridiales. A antibioticoterapia modificou a estrutura da comunidade bacteriana, entretanto não provocou queda no desempenho das aves. A comunidade bacteriana do intestino das aves medicadas e suplementadas com probiótico apresentou alta similaridade com a comunidade das aves que receberam apenas probiótico dietético, indicando a possível recuperação da microbiota intestinal aos 6 dias após a antibioticoterapia. / The purpose of this study was to verify the ability of a probiotic in the feed to maintain the stability of gut microbiota in chickens after antibiotic therapy and associations with the performance. The dietary treatments consisted of a cornsoybean meal basal diet that was supplemented or not with a probiotic (Bacillus subtilis) in the concentration of 3×109 cfu/kg of feed. Starting on day 21, the birds were submitted to the antibiotic therapy consisting of 200 ppm of bacitracin methylene disalicylate (for Gram-positive bacteria) and 1,000 ppm of neomycin sulfate (for Gram-negative bacteria) in the drinking water, during 3 days. The trial was conducted with broiler chickens from 1 to 42 days of age, however, from 1 to 21 days, the chickens received only the dietary treatment, and after of the 21 days, the birds received the dietary and therapeutic treatments. At 2, 4 and 6 days after the antibiotic therapy, three chickens from each experimental unit were euthanized and the contents of the small intestine and ceca were collected and pooled by pen. The trial was conducted in a completely randomized design with 4 treatments and 9 replicates in a 2×2 factorial arrangement for performance characteristics (with and without probiotic × with and without antibiotic therapy), and in a 2×2×3 factorial arrangement for gut microbiota (with and without probiotic × with and without antibiotic therapy × 2, 4 and 6 days after of the antibiotic therapy) with 3 replicates per treatment. The DNA was extracted from the contents of the small intestine and ceca to isolate the 16S r RNA and study of the bacterial communities. The molecular techniques used were the terminal restriction fragment length polymorphism (TRFLP), quantitative PCR (qPCR) and sequencing, considering the 16S rRNA -genetargeted. The dietary and therapeutic factors modulated the gut microbiota independently. The probiotic and antibiotic therapy affected the main groups within of the gut content from the phylogenetic classification at the phylum level until the phylogenetic classification at the genera level. Some phylogenetic groups were equally affected by the two factors while other groups were changed in a distinct form depending on of the probiotic or antibiotic therapy. The antibiotic therapy and dietary probiotic decreased the number of taxonomic operational unit (OTUs) in cecal content. The improved performance observed in birds supplemented with probiotic was probably related to changes in the structure of intestinal bacterial communities and phylogenetic groups such as higher Lactobacillus and decreased Clostridiales. Antibiotic therapy modified the bacterial community structure; however it did not cause loss of broiler performance. The gut bacterial community in birds medicated and supplemented with probiotic had high similarity with the gut community of birds that received dietary probiotic only, indicating the possible recovery of the gut bacterial community 6 days after the antibiotic therapy.

O objetivo deste estudo foi avaliar os efeitos da suplementação de Zn (na forma de ZnO nanoparticulado) em dietas para leitões recém-desmamados sobre o desempenho, a ocorrência de diarreia, a digestibilidade dos nutrientes, a excreção de Zn nas fezes, os parâmetros sanguíneos, a histologia do epitélio intestinal, a morfometria de órgãos e a contagem bacteriana no conteúdo intestinal em comparação ao uso de dose farmacológica de Zn (na forma de ZnO). Foram utilizados 192 leitões desmamados aos 21 dias, em um experimento em blocos casualizados, com 6 tratamentos, 8 repetições (blocos) e 4 animais por unidade experimental (baia). Os tratamentos foram: controle negativo - dieta basal com 100 mg de Zn/kg de ração (na forma de ZnO); controle positivo - dieta basal com 2400 mg de Zn/kg de ração (na forma de ZnO), e dieta basal com 12, 24, 48 ou 96 mg de Zn/kg de ração (na forma de ZnO-N). Os leitões foram alimentados com as dietas experimentais, durante os primeiros 21 dias de experimento. Dos 22 aos 35 dias, todos os animais foram alimentados com uma única dieta, com níveis basais de Zn. A ocorrência de diarreia foi registrada diariamente. Amostras de fezes foram coletadas para determinação da digestibilidade dos nutrientes da dieta e quantificação do Zn excretado. Amostras de sangue foram coletadas no 19° dia do experimento para análise dos parâmetros sanguíneos. No 21º dia, um animal de cada baia foi abatido para a realização da morfometria dos órgãos, histologia do epitélio intestinal e contagem bacteriana. Os dados foram submetidos à análise de variância e à regressão polinomial. Contrastes ortogonais foram utilizados para comparar o tratamento controle positivo com cada um dos níveis de Zn (na forma de ZnO-N). Não foram observados efeitos dos níveis de Zn (ZnO-N) sobre o desempenho, a excreção de Zn nas fezes, o hemograma, a morfometria de órgãos, a histologia do epitélio intestinal e a contagem bacteriana no conteúdo intestinal. O aumento dos níveis de Zn (ZnO-N) aumentou linearmente a digestibilidade aparente dos nutrientes da dieta. Foi observado efeito quadrático dos níveis de Zn (ZnO-N) sobre a frequência da ocorrência de diarreia entre os dias 1 e 7 e sobre a concentração plasmática de Zn. No período de 1 a 21 dias foi observado um menor consumo diário de ração para os níveis de Zn (ZnO-N) em comparação ao controle positivo. Não foram observados diferenças entre o controle positivo e os níveis de Zn (ZnO-N) para as variáveis de desempenho e a frequência da ocorrência de diarreia durante o período de 21 a 35 dias. Foi observada uma menor excreção de Zn nas fezes, e uma menor concentração plasmática de Zn para os níveis de Zn (ZnO-N) em comparação ao controle positivo. A suplementação de Zn, na forma de ZnO-N, não foi capaz de substituir a dose farmacológica de Zn (ZnO) no controle da diarreia após o desmame. Os níveis de Zn, na forma de ZnO-N, não ocasionaram toxicidade nos animais e propiciaram uma redução na excreção de Zn nas fezes. / The purpose of this study was to evaluate the effects of dietary Zn (as ZnO nanoparticles) on performance, diarrhea occurrence, nutrient digestibility, Zn excretion in the feces, blood parameters, histology of gut epithelium, organs morphometry and intestinal bacterial count of weanling pigs compared to the use of pharmacological doses of Zn (as ZnO). One hundred and ninety-two 21d-weaned pigs (5.90±0.83 kg BW) were used in a randomized complete block design experiment with 6 treatments, 8 replications per treatment, and 4 animals per experimental unit (pen). The treatments were: negative control (NC): basal diet (based on corn, soybean meal, dried whey and dried plasma) with 100 mg Zn (as ZnO)/kg diet; positive control (PC): basal diet with 2,400 mg Zn(as conventional ZnO, 150nm)/kg diet and basal diet with 12, 24, 48 or 96 mg Zn (as ZnO-N, 70nm)/kg diet. Pigs were fed dietary treatments from 1 to 21 d feeding period followed by a common diet (same diet for all treatments) from 22 to 35 d feeding period. Diarrhea occurrence was recorded daily. Feces samples were collected to determine the digestibility of the diet and to quantify the Zn excreted. Blood samples were collected on the 19th day of the experiment for analysis of blood parameters. On the 21th day one pig per pen was slaughtered for the analyses of organs morphometry, intestinal epithelium histology and bacterial count. ANOVA and polynomial regression analysis (for levels of Zn as ZnO-N) were performed. Orthogonal contrasts were used to compare positive control with each level of Zn (as ZnO-N). No effects of Zn levels (as ZnO-N) were observed on performance, Zn excretion on feces, blood count, organs morphometry, intestinal epithelium histology and intestinal bacterial count. Increased levels of Zn (as ZnO-N) linearly increased the apparent digestibility of nutrients. It was observed a quadratic effect of Zn levels (as ZnO-N) on the frequency of diarrhea occurrence between 1 and 7 d and on the Zn plasma concentration. From 1 to 21 d of experimental period, lower daily feed intake for Zn levels (as ZnO-N) was observed compared to positive control. No differences were observed among the positive control and levels of Zn (as ZnO-N) for performance and diarrhea occurrence during the period 21 to 35 d. Lower Zn excretion in feces and lower Zn plasma concentration were observed for Zn levels (as ZnO-N) compared to the positive control. Zn supplementation, as ZnO-N, could not to replace the pharmacological dose of Zn (ZnO) to control diarrhea after weaning. The levels of Zn, as ZnO-N, did not cause toxicity of weanling pigs and reduced Zn excretion in the feces.