RESUMO
This study examined neutrophil and monocyte functions and the blood lymphocyte profile of naturally BLV-infected cows with or without persistent lymphocytosis (PL). The percentage of neutrophils and monocytes that phagocytosed Staphylococcus aureus was lower in BLV-infected dairy cows, particularly those with PL. The relative percentage of CD44+ monocytes and neutrophils and CD11b expression by neutrophils was also lower in BLV-infected dairy cows with PL. A correlation between the percentage of CD11b+ neutrophils and that produced reactive oxygen species (ROS) was found. Furthermore, the percentage of CD44+ monocytes was positively correlated with the percentage of monocytes that phagocytosed S. aureus and the same phenomenon was observed for neutrophils. In BLV-infected dairy cows, particularly those with PL, inhibition of monocyte and neutrophil apoptosis was observed. Additionally, the percentage of neutrophils producing ROS was lower in BLV-infected cows with PL, in contrast to higher intensity of intracellular production of ROS by monocytes. The result from the lymphocyte immunophenotyping of BLV-infected cows with PL was an increase in B cells, mainly B CD5+ CD11b+, due to the apoptosis inhibition. In conclusion, this study provides novel insight into the implications of BLV infection for cattle, which can include the dysfunction of blood monocytes and neutrophils.
Assuntos
Leucose Enzoótica Bovina/virologia , Vírus da Leucemia Bovina/imunologia , Animais , Linfócitos B/metabolismo , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Bovinos , Leucose Enzoótica Bovina/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Imunofenotipagem , Linfócitos/imunologia , Linfocitose , Monócitos/imunologia , Neutrófilos/imunologia , Fagocitose , Staphylococcus aureus/fisiologiaRESUMO
Corynebacterium bovis is one of the most commonly isolated bacteria from aseptically collected bovine milk samples. The objective of the current study was to characterize the bovine innate immune response by evaluating milk polymorphonuclear neutrophilic leukocytes (PMNL) in mammary glands infected with C. bovis. Twenty quarters infected with C. bovis and 28 culture-negative quarters (with milk somatic cell count <1×10(5) cells/mL) were used. The percentages of milk PMNL and the PMNL expression of L-selectin (CD62L), ß2-integrin (CD11b), and one of the endothelial-selectin ligands (CD44), as well as the levels of intracellular reactive oxygen species (ROS) and the phagocytosis of Staphylococcus aureus, were evaluated by flow cytometry. The apoptosis and necrosis rates of the PMNL were quantified using dual-color flow cytometry with fluorescein-labeled annexin and propidium iodide. The present study revealed a higher percentage of PMNL in the milk from C. bovis-infected quarters, although no significant differences were found in levels of CD44, CD62L, or CD11b expression among the PMNL. A lower percentage of apoptotic PMNL was observed in C. bovis-infected quarters, as well as higher percentages of viable PMNL and of PMNL that produced intracellular ROS. However, no alterations were observed in phagocytosis of Staph. aureus by the PMNL or in intensity of intracellular ROS production by PMNL. Thus, results from this investigation of the PMNL function support, at least in part, the fact that intramammary infections by C. bovis may offer protection against intramammary infections by other bacteria.
Assuntos
Infecções por Corynebacterium/imunologia , Corynebacterium/imunologia , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Leite/imunologia , Neutrófilos/imunologia , Animais , Antígeno CD11b/imunologia , Bovinos , Separação Celular/veterinária , Corynebacterium/isolamento & purificação , Feminino , Receptores de Hialuronatos/imunologia , Selectina L/imunologia , Leite/citologia , Leite/microbiologia , Neutrófilos/citologia , Fagocitose , Espécies Reativas de Oxigênio/metabolismoRESUMO
Com este estudo objetivou-se avaliar o potencial anestésico do tramadol, após bloqueio infiltrativo, comparativamente ao da lidocaína, para realização de biópsia de pele em eqüinos. Oito cavalos, adultos, foram submetidos à biópsia de pele, após bloqueio infiltrativo com tramadol 2,5% (GT), ou com lidocaína 1% (GL). Atributos estudados: período de latência(PL), duração do bloqueio (DB), ocorrência de alterações de pele (AP), qualidade da anestesia (QA), freqüências cardíaca(FC) e respiratória (f) e temperatura retal (TR). Momentos estudados: FC, f e TR: antes do bloqueio local e a cada 15 minutos, até o término da anestesia. PL: imediatamente após a infiltração dos fármacos até a perda da resposta sensitiva. DB: a partir do início do efeito anestésico, até o restabelecimento da sensibilidade. O teste de sensibilidade foi realizado a cada 10 minutos, mediante estímulo nociceptivo mecânico. A estatística foi realizada com análise de variância, teste de Tukey, teste t não pareado e teste de Mann-Whitney. Não foram constatadas diferenças significativas na FC, TR e na QA entre os grupos nos diferentes momentos. A f foi significativamente inferior durante o procedimento cirúrgico, em relação aos valores basais e aos valores observados ao término do procedimento cirúrgico, em ambos os grupos. O PL foi significativamente maior para o GT. A DB não diferiu entre os grupos. Nenhuma AP foi