OBJECTIVETo investigate the prevalence of serum antibodies against Japanese encephalitis virus (JEV) in bats.

METHODSBlood samples from the heart were obtained from bats captured in Guangdong and Hainan Provinces in 2013. The anti-JEV antibodies in bat sera were tested using indirect ELISA and virus neutralization test.

RESULTSA total of 201 bat serum samples were tested, in which the total positivity rate of anti-JEV antibodies was 46.27% (93/201). The positive rate of anti-JEV antibodies in bats from Hainan and Guangdong Provinces was 88.89% (48/54) and 30.61% (45/147), respectively. All the samples from Rousettus leschenaultia, Miniopterus schreibersii, Pipistrellus abramus, and Rhinolophus macrotis were positive for anti-JEV antibodies, and up to 95.56% (43/45) of the samples from Miniopterus schreibersii (from Hainan Province) yielded positive results. Of the 28 samples with positive results by indirect ELISA, 15 showed positive results in virus neutralization test (53.57%) with neutralization antibody titers ranging from 1:10 to 1:28.22.

CONCLUSIONBats from different regions and of different species can be naturally infected with JEV and have a high prevalence of anti-JEV antibodies in their sera. The role of bats in the natural cycle of JEV awaits further study.

Animals ; Antibodies, Viral ; blood ; China ; Chiroptera ; immunology ; virology ; Encephalitis Virus, Japanese ; Enzyme-Linked Immunosorbent Assay ; Neutralization Tests

OBJECTIVE To investigate the in vitro anti-inflammatory effects and mechanisms of oblongifolins A （OA） extracted from Garcinia oblongifolia. METHODS RAW264.7 cells were used as the research subject and divided into control group （0.5% DMSO）， lipopolysaccharide （LPS） group （1 μg/mL）， DEX group （10 µmol/L DEX+1 μg/mL LPS）， and low-， medium-， and high-concentration groups of OA （7.5， 15， 30 µmol/L OA+1 μg/mL LPS）. Except for the control group， the remaining groups were first stimulated with LPS for 1 hour and then mixed with drugs for 24 hours. The morphological changes of cells were observed in each group. The contents of nitric oxide （NO）， reactive oxygen species （ROS）， tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， IL-1β， IL-4 and IL-10 were detected in cells of each group； mRNA expression levels of TNF-α， IL-6 and IL-1β were measured. The expression of key proteins in the nuclear factor κB （NF-κB） and nuclear factor-erythroid 2-related factor 2 （Nrf2） signaling pathways in each group， as well as the nuclear translocation of NF-κB p65 and Nrf2 proteins in control group， LPS group and OA high-concentration group， were detected. RESULTS Compared to the LPS group， the number of spindle-shaped and irregular cells gradually decreased in OA groups， the contents of NO， ROS （except for OA low-concentration group）， TNF-α， IL-6 and IL-1β， the mRNA expressions of TNF-α， IL-6 （except for OA low-concentration group） and IL-1β as well as the protein expressions of phosphorylated NF-κB p65 （p-NF-κB p65）， p-IκBα， and Kelch-like ECH-associated protein 1 （Keap1） were decreased significantly （P＜0.05）. The contents of IL-4 and IL-10， protein expressions of IκBα， Nrf2 （except for OA low- and medium-concentration groups）， HO-1 （except for OA low-concentration group） and NQO1 were all increased significantly （P＜0.05）. OA of high concentration could inhibit NF-κB p65 protein nuclear translocation and promote Nrf2 protein nuclear translocation. CONCLUSIONS OA can suppress LPS-induced inflammation in RAW264.7 macrophages. The underlying molecular mechanism likely entails the inhibition of the NF-κB signaling pathway， the activation of the Nrf2 signaling pathway and the reduction of ROS and inflammatory factor release.