RESUMEN
Uma preparaçäo antigênica bruta de Babesia bovis, preparada a partir de cultivo celular, foi liofilizada e utilizada em um teste de ELISA para detecçäo de anticorpos. O valor discriminante foi calculado pela média de amostras de soros negativos acrescida de dois desvios padröes. As duas séries de valores obtidas com antígeno liofilizado e antígeno congelado mostraram alta correlaçäo, indicando que a liofilizaçäo pode se constituir em uma alternativa prática para preservaçäo de antígenos de B. bovis para uso em ELISA
Asunto(s)
Animales , Anticuerpos , Antígenos , Babesia bovis/inmunología , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
A series of racemic 16:0 disaturated N-substituted diether phosphonolipid analogs of glycerophospholipids have been synthesized and purified. Isosteric methylene substitution at three of the four ester sites (carboxyl, phosphate) of conventional glycerophospholipids enhanced the hydrophobicity of analog compounds compared with dipalmitoyl phosphatidylcholine (DPPC), the major glycerophospholipid component of lung surfactant. Further substitutions at the nitrogen headgroup also contributed to hydrophobicity/hydrophilicity characteristics, as well as allowing graded variations in headgroup size among the members of the diether phosphonolipid analog series. Interfacial property studies showed that these compounds had significant differences in surface activity characteristics compared with DPPC, including increased adsorption and respreading facility, plus an enhanced ability to generate low surface tension (less than 1 to 4 mN/m) on an oscillating bubble apparatus at 37 degrees C. In addition, pressure-volume mechanical studies in surfactant-deficient excised rat lungs showed that the diether phosphonate analog of DPPC could partially restore pressure-volume characteristics toward normal, both as a pure component and in binary mixtures with palmitoyl-oleoyl phosphatidylglycerol. These findings suggest that selected analog compounds, synthesized with relatively small structural modifications from biologic glycerophospholipids, may have eventual applications as components of synthetic exogenous lung surfactants. Of more immediate importance, analog molecules with defined structural variations are convenient molecular probes for developing structure-surface activity correlates for phospholipid-like surfactants and for investigating the specificity of interactions between glycerophospholipids and other compounds such as proteins.
Asunto(s)
Éteres/síntesis química , Pulmón/efectos de los fármacos , Fosfolípidos/síntesis química , Surfactantes Pulmonares/síntesis química , 1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , 1,2-Dipalmitoilfosfatidilcolina/farmacología , Animales , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Éteres/farmacología , Membrana Dobles de Lípidos , Pulmón/fisiología , Modelos Biológicos , Fosfolípidos/farmacología , Surfactantes Pulmonares/farmacología , Ratas , Tensión Superficial/efectos de los fármacosRESUMEN
Calves were immunized with Boophilus microplus saliva, filtered through Millipore membranes, in Freund's complete adjuvant. Serum samples were tested by passive hemagglutination against Babesia bigemina, Anaplasma marginale, B. microplus larvae extract, Stomoxys calcitrans extract and B. microplus saliva. After immunization, titers to saliva, larval tick-extract and to S. calcitrans were increased. The challenge with live tick larvae enhanced the formation of antibodies against larva extract, fly extract and tick saliva, which supports the idea that under natural controlled conditions this cross-reactivity could occur.