ObjectiveTo assess the occurrence of Leptospira spp serovar Hardjo among Zebu cattle in some livestock producing areas of Kaduna State, Nigeria.MethodsSera samples were obtained from 164 Zebu breed of cattle above one year osf age in seven cattle farms were screened for antibodies to Leptospira spp. serovar Hardjo using Enzyme linked immunosorbent assay (ELISA).ResultsAntibodies to Leptospira spp. serovar Hardjo were detected in eighteen (10.98%) out of the 164 animals sampled. There was no significant difference (P>0.05) in seropositivity between the different age groups or between different Zebu breeds.ConclusionThe presence of Leptospirosis among the Zebu breeds of cattle may poses a threat to livestock production and has public health implication due to its zoonotic potential. 相似文献
Objective To investigate the role of hypoxia-inducible factor-2α (HIF-2α) in the expression of tight junction proteins and permeability alterations in rat glomerular endothelial cells (rGENCs) under hypoxia condition. Methods The expressions of the HIF-2α and tight junction proteins such as occludin and ZO-1 of rGENCs were examined after exposed to 5% oxygen at different treatment time periods (0 h, 12 h, 24 h and 48 h). Then lentiviral transfection was used to knock down HIF-2α expression in rGENCs. The cells were split into four groups, including i) control group where rGENCs were cultured under normal oxygen conditions, ii) hypoxia group, iii) negative control group where rGENCs were infected with a negative vector, iv) HIF-2α lentivirus transfection group. Group ii, iii and iv were kept in hypoxic chamber (5% O2, 5% CO2 and 90% N2) for 24 h. The expressions of occludin, ZO-1 and HIF-2α were assessed by Western blotting. The permeability of rGENCs was measured using trans-epithelium electrical resistant (TEER) by Millicell? ERS voltohmmeter. Results With the elongation of hypoxia time, the expression of HIF-2α was increased gradually, while the occludin expression was decreased, there was statistically significance difference in each group (all P<0.01). The expression of ZO-1 also decreased gradually under hypoxia circumstance, but no statistically significant was found between 24 h and 48 h groups (all P>0.05). And a dramatic decrease in TEER of hypoxia cells was detected as compare with control cells (P<0.01). After knockdown of HIF-2α expression, both expressions of occludin and ZO-1 were increased significantly compared with hypoxia cells (P<0.01), and TEER elevated at the same time (P<0.01). Above indexes had no statistical difference between hypoxia cells and negative control cells (all P>0.05). Conclusion Hypoxia may promote HIF-2α expression, which could increase the permeability of rGENCs by reducing the expression of occludin and ZO-1. 相似文献