A novel syndrome of severe neutrophil dysfunction: unresponsiveness confined to chemotaxin-induced functions.

We have identified a patient with a number of neutrophil dysfunctions. The patient was a female baby who lived for 8 months. During her life, she developed severe bacterial infections and showed omphalitis, impaired wound healing, and a pronounced leukocytosis. She was not a patient with leukocyte adhesion deficiency, because all leukocyte CD18 complex proteins were expressed at normal levels. Yet, neutrophil polarization and chemotaxis to platelet-activating factor, leukotriene B4, or formyl-methionyl-leucyl-phenylalanine (FMLP) were completely absent. We found a strong defect in actin polymerization in response to chemotactic stimuli, but only a retarded or even normal reaction with other stimuli. This indicates that the cellular dysfunctions were not due to an intrinsic defect in actin metabolism. Instead, the regulation of actin polymerization with chemotactic stimuli seemed to be defective. We concentrated on FMLP-induced responses in the patient's neutrophils. Functions dependent on activation of complement receptor type 3, such as aggregation or adherence to endothelial cells, were normally induced. Binding to serum-coated coverslips was normal in cell number; however, spreading was not observed. Exocytosis from the specific granules was readily induced. In contrast, FMLP failed to induce a respiratory burst activity or degranulation of the azurophil granules. FMLP induced a normal increase in free intracellular Ca2+, but a decreased formation of diglycerides (especially the 1-O-alkyl,2-acyl compounds). Thus, we have described a patient whose neutrophils show a severe defect in functional activation via chemotaxin receptors, resulting in a selective absence of NADPH oxidase activity, exocytosis from the azurophil granules, and actin polymerization. Our findings show that actin polymerization for neutrophil spreading and locomotion is regulated differently from that for phagocytosis. Also, the release of azurophil and specific granule contents is clearly shown to be regulated in a different way.

Correlação entre os métodos de concepção, ocorrência e formas de tratamento das onfalopatias em bovinos: estudo retrospectivo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação da eficácia da clorexidina na cicatrização da região umbilical de avestruzes Struthio camelus (Linnaeus 1758)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Trueperella pyogenes multispecies infections in domestic animals: a retrospective study of 144 cases (2002 to 2012)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeito da clorexidina na cicatrização umbilical de avestruzes

The contamination of the umbilical region of newly hatched ostriches is one of the major problems in the bird production. This work aimed to evaluate the umbilical healing of ostriches (Struthio camelus) through the use of chlorhexidine as antiseptic associated to the total or partial umbilical cord cut off. It was used 168 newly hatched ostriches of which the umbilical cords were either sectioned totally or 0.5 cm above their insertion. The umbilical region antisepsis consisted of topical administration of an aqueous or alcoholic solution of chlorhexidine, 0.5, 1.0 or 2.0% during three days. A group of non-treated animals was added also. The umbilical healing was evaluated in the ostriches at 14 and 28 days of age. Results showed that all the chlorhexidine solutions reduced the risk of omphalitis, being the alcoholic solution 2% the most efficient. Umbilical healing was faster in animals in which the umbilical cord was totally cut off. It can be concluded that the use of chlorhexidine as antiseptic for newly hatched ostriches is safe and favors the umbilical healing. Moreover, for a better effectiveness it is necessary to remove the umbilical cord in its insertion

Índice de resistência múltipla aos antimicrobianos, concentração inibitória e beta-lactamases de espectro estendido em linhagens de Proteus mirabilis e Proteus vulgaris isoladas de diferentes afecções em animais domésticos

Pós-graduação em Medicina Veterinária - FMVZ