Seroepidemiology and genetic characterization of hepatitis E virus in western Yunnan Province

ABSTRACTObjectiveTo investigate the seroepidemiology and genetic characterization of hepatitis E virus (HEV) in western Yunnan Province.MethodsQuestionnaire survey was conducted among 1638 residents in western Yunnan Province using stratified sampling method. Enzyme-linked immunosorbent assay was used to detect serum anti-HEV IgG and IgM. HEV RNA was extracted from patients with serum anti-HEV IgM positive. The open reading flame 2 (ORF2) of HEV that was amplified by nested RT-PCR was sequenced and compared with standard HEV genotypes 1-4.ResultsSerum anti-HEV positive was found in 13.92% (228/1638) residents. The HEV infection rate in males was significantly higher than that in females with a ratio of 1.47 (P<0.01). 20-30 and 30-40 years old young men showed the highest incidence, 20.57% and 20.78%, respectively. While 10-20 and 20-30 years old young women exhibited the highest infection rate, 11.85% and 15.60%, respectively. According to occupation, the highest HEV infection rate was observed in farmers (20.35%) and migrants (16.50%). We isolated 10 individual HEV isolates from 31 patients with serum anti-HEV IgM positive. Homology analysis and phylogenetic analysis indicated that these 10 HEV isolates belonged to HEV genotype 4 with the homology of 78.65%-94.71%.ConclusionsThe HEV infection rate is high in western Yunnan Province. HEV genotype 4 is the leading cause of HEV infection and young farmers and migrants are the main infected population

Effect of ammonia on the immune response of mud crab (Scylla paramamosain) and its susceptibility to mud crab reovirus

Ammonia is one of the major environmental pollutants that affect the growth and physiological functions of organisms. In the present study, the effects of ammonia on the immune response and pathogen resistance of mud crab reovirus (MCRV) in mud crab were investigated. Mud crab were exposed to four different ammonia concentrations (0, 2.5, 5 and 10 mg L-1 ammonia-N) for 7 d. The result showed that aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activity significantly increased after 5 and 10 mg L-1 ammonia exposure. The hepatopancreas superoxide dismutase (SOD), catalase (CAT), and total antioxidative capacity (T-AOC) in ammonia-N group were significantly lower than those in the control group, while the levels of malondialdehyde (MDA) were significantly higher than those in the control group. Significant reductions in total hemocyte counts (THC) were observed after ammonia exposure. After 7d ammonia exposure, mud crabs were injected 100 μL MCRV at 105 copies/g body weight. The mortality of mud crabs in ammonia-N group were significantly higher than those in the control group. All these results suggested that ammonia in water caused a depression in the immune response, and increased susceptibility to MCRV infection

Experimental Free-Space Distribution of Entangled Photon Pairs over a Noisy Ground Atmosphere of 13km

We report free-space distribution of entangled photon pairs over a noisy ground atmosphere of 13km. It is shown that the desired entanglement can still survive after the two entangled photons have passed through the noisy ground atmosphere. This is confirmed by observing a space-like separated violation of Bell inequality of $2.45 \pm 0.09$. On this basis, we exploit the distributed entangled photon source to demonstrate the BB84 quantum cryptography scheme. The distribution distance of entangled photon pairs achieved in the experiment is for the first time well beyond the effective thickness of the aerosphere, hence presenting a significant step towards satellite-based global quantum communication.Comment: 4 pages, 3 figure

De novo intestine-specific transcriptome of the brown planthopper Nilaparvata lugens revealed potential functions in digestion, detoxification and immune response

AbstractThe brown planthopper (Nilaparvata lugens, BPH) is the most serious rice plant pests in Asia. In this study, we performed transcriptome-wide analysis on BPH intestine. We obtained more than 26 million sequencing reads that were then assembled into 53,553 unigenes with a mean size of 388bp. Based on similarity search with the nucleotide sequences available at NCBI, BPH intestine-specific transcriptome analysis identified 21,405 sequences. Assembled sequences were annotated with gene description, gene ontology and clusters of orthologous group terms. The digestion-, defense- and xenobiotic metabolism-related genes were abundantly detected in the transcripts from BPH intestine. Many novel genes including 33 digestion-related genes, 25 immune responsive genes and 27 detoxification-related genes are first reported here. We investigated the gene expression patterns at the transcript levels in different tissues by quantitative real-time PCR analysis, which revealed that some genes had intestine-specific expression, implicating their potential significance for BPH management