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1.
Res Vet Sci ; 117: 260-265, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29331687

RESUMO

There have been significant efforts toward the development of more efficient vaccines for animal health. A strategy that may be used to improve vaccine efficacy is the use of probiotics. Bovine herpesvirus 5 (BoHV-5) is an example of an important animal pathogen for which vaccines have provided only limited protection. In this study, we examined the use of the probiotics Bacillus toyonensis and Saccharomyces boulardii as a potential immune modulator to improve vaccine efficiency. Thirty, 5-month-old lambs were randomly grouped in three lots of 10 each and vaccinated at days 0, 21 and 42 of the experiment. They grazed on the same pasture and were fed ad libitum twice a day with commercial sheep feed supplemented with either B. toyonensis (1×106CFU/g of feed) or S. boulardii (1×107CFU/g of feed), or non-supplemented feed. The probiotic supplementation was suspended day 28; thereafter, the next 35days, they were fed with the same commercial feed as control group. Animals supplemented with probiotics showed a significant (p>0.001) increased seroconversions against BoHV-5, and higher neutralizing antibodies titres (p>0.05) to BoHV-5 than non-supplemented animals. At 63days of experiment, splenocytes from the supplemented sheep had higher mRNA transcription levels of cytokines IL-10 and IL-17A. These results suggest that these probiotics could provide a promising means of improving vaccine efficacy.


Assuntos
Bacillus/imunologia , Herpesvirus Bovino 5/imunologia , Saccharomyces boulardii/imunologia , Vacinas Virais/imunologia , Ração Animal , Animais , Bovinos , Imunomodulação/efeitos dos fármacos , Probióticos/farmacologia , Ovinos
2.
Ciênc. rural ; 45(12): 2201-2206, graf
Artigo em Inglês | LILACS | ID: lil-764511

RESUMO

Genus Salmonella bacteria are among the major pathogenic microorganisms in food. This bacterium pathogenicity is related to a number of virulence factors, among which its flagella. Flagellum expression is one of the virulence factors modulated by Quorum Sensing. Epinephrine produced by mammals uses the same signaling pathway of the 3 bacteria autoinducer. This study evaluated the effect of molecules inducer (epinephrine) and autoinducers (autoinducer 2 and autoinducer 3) and their association with the motility, growth and expression genes flhC, fliA, fliY, motA, motB e fliC of Salmonella Typhimurium (ST). Initially, ST was inoculated in BHI. Then, motility assays, growth curves and gene expression were performed by testing different concentrations of epinephrine (50, 125, 250, 500µM), conditioned medium (10 and 50%) and a combination of these. ST was exposed to different concentrations of epinephrine, conditioned medium and an association of both. Following, motility assays, bacterial growth and gene expression were performed. The results obtained showed that the combination of 500uM epinephrine with 50% conditioned medium increased ST bacterial motility by increasing the expression of genes involved in flagellum assembly.


Salmonella está entre os principais micro-organismos patogênicos veiculados por alimentos. A patogenicidade dessa bactéria está relacionada a uma série de fatores de virulência e, dentre estes, podemos citar os flagelos. A expressão do flagelo está entre os fatores de virulência modulados por Quorum Sensing. A adrenalina produzida pelos mamíferos utiliza a mesma via de sinalização do autoindutor 3 das bactérias. Nesse sentido, este trabalho teve como objetivo avaliar o efeito de moléculas indutora (adrenalina) e autoindutoras (auto-indutor 2 e auto-indutor 3) e a associação destas na motilidade, no crescimento celular e na expressão dos genes flhC, fliA, fliY, motA, motB e fliC de SalmonellaTyphimurium (ST). Inicialmente, ST foi semeada em caldo BHI. Após, ensaios de motilidade, curvas de crescimento e expressão gênica foram feitos, testando diferentes concentrações de adrenalina (50, 125, 250, 500µM), meio condicionado (10 e 50%) e a associação destes. A partir dos resultados obtidos, observou-se que o tratamento que utilizou 50% de meio condicionado + 500µM de adrenalina aumentou a motilidade de ST, em decorrência do aumento de genes envolvidos com montagem do flagelo.

3.
Vet Microbiol ; 180(3-4): 245-52, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26386492

RESUMO

Quorum sensing (QS) is a signaling system among bacteria mediated by auto-inducer substances (AI). Whenever the concentration of these molecules reaches a threshold corresponding to a high cell density or quorum, the whole population starts a coordinated expression of specific genes. Studies have shown that epinephrine is also responsible for activating specific bacterial genes. This work aimed to investigate the role of conditioned medium (containing AI), epinephrine and their association on growth, motility, F4 fimbriae and heat-labile toxin (LT) expression on enterotoxigenic Escherichia coli (ETEC, E68). A significant increase in motility, F4 and LT expression, was observed in the ETEC culture supplemented with conditioned medium and epinephrine. These findings suggest that ETEC uses some components of conditioned medium (e.g., AI molecules), host molecules (epinephrine), and their association to modulate the expression of important virulence genes.


Assuntos
Escherichia coli Enterotoxigênica/genética , Proteínas de Escherichia coli/genética , Percepção de Quorum , Fatores de Virulência/genética , Antígenos de Bactérias/genética , Toxinas Bacterianas/genética , Meios de Cultivo Condicionados , Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Enterotoxinas/genética , Epinefrina/farmacologia , Proteínas de Fímbrias/genética , Genes Bacterianos , Transdução de Sinais , Virulência
4.
Neurochem Res ; 40(7): 1421-30, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25998886

RESUMO

Cecropia species are widely used in traditional medicine by its anti-diabetic, anti-hypertensive and anti-inflammatory properties. In the present study, we investigated the neuroprotective and antioxidant effects of the crude aqueous extract from Cecropia pachystachya leaves in a rat model of mania induced by ketamine. The results indicated that ketamine treatment (25 mg/kg i.p., for 8 days) induced hyperlocomotion in the open-field test and oxidative damage in prefrontal cortex and hippocampus, evaluated by increased lipid peroxidation, carbonyl protein formation and decreased total thiol content. Moreover, ketamine treatment reduced the activity of the antioxidant enzymes superoxide dismutase and catalase in hippocampus. Pretreatment of rats with C. pachystachya aqueous extract (200 and 400 mg/kg p.o., for 14 days) or with lithium chloride (45 mg/kg p.o., for 14 days, used as a positive control) prevented both behavioral and pro-oxidant effects of ketamine. These findings suggest that C. pachystachya might be a useful tool for preventive intervention in bipolar disorder, reducing the episode relapse and the oxidative damage associated with the manic phase of this disorder .


Assuntos
Transtorno Bipolar/prevenção & controle , Ketamina/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Urticaceae/química , Animais , Comportamento Animal , Cromatografia Líquida de Alta Pressão , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Locomoção/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Wistar
5.
Anim Sci J ; 85(11): 963-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24990486

RESUMO

Colostrum silage is an anaerobic fermentation methodology of excess farm colostrum used to conserve and provide as milk replacement for calves. The present study aimed to evaluate the levels of immunoglobulins present in bovine colostrum silage and its absorption by newborn calves. The concentration of immunoglobulins was determined in fresh colostrum and colostrum silage stored for 12 months. The absorption of immunoglobulins by calves was assessed immediately after birth and 24 h after colostrum silage intake. The immunoglobulin levels were evaluated by ELISA. The results highlighted that colostrum silage kept similar levels of immunoglobulins as the ones in colostrum in natura, and can be transferred to newborn calves with similar amounts to calves fed with colostrum in natura. It is concluded that colostrum silage keeps viable immunoglobulins, and is able to transfer passive immunity to newborn calves.


Assuntos
Animais Recém-Nascidos/imunologia , Animais Recém-Nascidos/metabolismo , Bovinos/imunologia , Bovinos/metabolismo , Colostro , Imunidade Materno-Adquirida/imunologia , Imunoglobulinas/imunologia , Imunoglobulinas/metabolismo , Silagem , Animais , Colostro/química , Colostro/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulinas/análise , Masculino , Silagem/análise
6.
Rev. bras. farmacogn ; 20(3): 409-415, jun.-jul. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-555923

RESUMO

Algumas das substâncias presentes nos vegetais podem ter efeitos mutagênicos, enquanto outras podem atenuar ou anular estes efeitos. Estima-se que mais de 200 substâncias ativas façam parte do gel de Aloe vera, sendo que os polissacarídeos chegam a 30 por cento, e muitos dos benefícios terapêuticos, nutricionais e cosméticos são a eles atribuídos. O objetivo deste trabalho foi determinar o efeito mutagênico e antimutagênico da solução de Aloe vera, em teste de Allium cepa e teste de micronúcleos em linfócitos humanos binucleados. Para as soluções, as folhas de Aloe vera foram trituradas, filtradas e esterilizadas. O teste de Allium cepa foi constituído de oito tratamentos e o de linfócitos, de cinco (com quatro repetições). Observou-se que na dose usual, a solução de Aloe vera não foi mutagência para o sistema de teste vegetal e nem para o humano. Já na dose dez vezes mais concentrada provocou um efeito citotóxico e mutagênico em Allium cepa. Em células vegetais a solução foi antimutagênica apenas quando colocada depois do paracetamol, enquanto que nas células humanas, essa ação se manifestou quando a solução foi utilizada ao mesmo tempo com o paracetamol.


Some of the substances in plant may have mutagenic effects, while others may cancel or mitigate these effects. It is estimated that more than 200 active substances compose the gel of Aloe vera, and the polysaccharides increases in 30 percent, and many of the therapeutic benefits, nutrition and cosmetics are allocated to them. The objective of this study was to determine the mutagenic and antimutagenic effects of the Aloe vera solution in Allium cepa test and the micronuclei test in human binucleated lymphocytes. For solutions, the leaves of Aloe vera were crushed, filtered and sterilized. The Allium cepa test was composed of eight treatments, and the lymphocytes of five (with four repetitions). It was observed that at the usual dose, the solution of Aloe vera was not mutagenic for the plant test system and not for humans. At a dose ten times more concentrated caused a cytotoxic and mutagenic effect in Allium cepa. In plant cells the solution was antimutagenic only when placed after paracetamol, while in human cells, this action was manifested when the solution was used at the same time with paracetamol.

7.
Rev. bras. farmacogn ; 20(2): 165-170, Apr.-May 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-550010

RESUMO

A carqueja (Baccharis trimera(Less.) DC.) é uma planta medicinal da família Asteraceae muito utilizada como chá no sul do Brasil no tratamento de doenças renais, intestinas, estomacais e principalmente como emagrecedora. O objetivo desde trabalho foi de avaliar a mutagenicidade in vivoe in vitrodo chá e para isso foi realizado o teste de Allium cepaL. e o de aberrações cromossômicas em linfócitos humanos utilizando quatro tratamentos: T1 (água); T2 (20 g/L de carqueja); T3 (200 g/L de carqueja), e T4 (paracetamol, a 400 mg/L). Ambos os procedimentos foram analisados pelo teste Mann-Whitney U. Este estudo evidencia um efeito mutagênico do chá em células vegetais (Allium cepa) e em células humanas (aberrações cromossômicas) cultivadas, pois em ambos os testes, T2 e T3 obteve-se uma média mais elevada que nos outros tratamentos. Este estudo demonstra que o efeito é dependente da dose, portanto recomenda-se que o chá de carqueja seja consumido com moderação.


Broom (Baccharis trimera(Less.) DC.) is a medicinal plant from Asteraceae that is commonly used as a tea in the south of Brazil for the treatment of renal, intestinal and stomach diseases. It is also used as a slimming agent. The aim of this study was to evaluate the mutagenicity of the tea in vivoand in vitro. In order to do this, the Allium cepatest was carried out and the chromosomal aberrations in human lymphocytes were tested using four treatments: T1 (water); T2 (20 g/L of broom); T3 (200 g/L of broom) and T4 (paracetamol at 400 mg/L). Both procedures were analyzed using the Mann-Whitney U test. This study provided evidence of a mutagenic effect of the tea in vegetable cells (Allium cepa) and in cultivated human cells. In tests T2 and T3 there was a higher average than the other treatments. This study shows that the effect is dependent on the dose. It is therefore recommended that broom tea be consumed with moderation.

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