RESUMO
Probióticos são microrganismos vivos que, se administrados em quantidades adequadas, promovem benefícios à saúde do homem e dos animais. O crescente interesse nos probióticos fundamenta-se em estudos clínicos nos quais a administração desses organismos foi avaliada na prevenção e no tratamento de desordens intestinais e sistêmicas. Os potenciais mecanismos de ação desses microrganismos incluem a exclusão competitiva, a produção de metabólitos com atividade antimicrobiana e a modulação da resposta imune. Em algumas circunstâncias clínicas específicas, os benefícios produzidos por esses microrganismos foram amplamente documentados, enquanto que em outras os resultados são contraditórios. No presente artigo de revisão, os probióticos foram abordados considerando-se o potencial bioterapêutico desses microrganismos nas parasitoses intestinais.
Probiotics are live microorganisms which, when administered in adequate amounts, beneficially affect the general health status of man and animal. The great interest in probiotic microganisms is based on evidences from clinical studies indicating benefits in the prevention or treatment of a broad spectrum of gastrointestinal and systemic disorders. The potential mechanisms by which probiotics beneficially affect health include strengthening of the intestinal barrier, modulation of the immune response, and antagonism of pathogens either by the production of antimicrobial compounds or through competition for mucosal binding sites. In some specific clinical circumstances, there is clear evidence of benefit whereas in others, the results are dubious and important questions remaining unanswered. The aim of this review article is to focus probiotics on their potential as biotherapeutic agents against intestinal parasites.
RESUMO
S-100 dendritic cells immunolabeling were investigated in uninfested skin biopsies from five Nelores, five Holstein-Friesian and five crossbreed (Holstein-Friesian x Nelores) calves. The group of crossbreed animal was experimentally infested with 100 first-instar larvae of Dermatobia hominis and biopsies were obtained 24, 48, 72 and 168 hours after infestation. Samples obtained prior to infestation from these animals were used as control. Rabbit anti-protein S-100 antibody and the avidin-biotin-peroxidase method were used for immunolabeling. Melanocytes, nerves and endothelial cells and dermal dendritic cells (DC) were positive to protein S-100. DCs were exclusively detected in the superficial dermis close to the basal layer of both normal and parasitized animals. There was no significant difference in DC numbers that might be attributed to breed. In parasitized animals the DC had thicker and deeply stained dendritic processes compared to normal animals. Statistically significant decreases in the DC number occurred after infestation