| Hepatitis E , the principal cause of enterrically transmitted, was once considered non-A non-B hepatitis. It is a very important public health concern in many developing countries where epidemics of hepatitis E are common. The disease generally affects young adults.Although the overall mortality rate associated with HEV infection is low, it is reportedly as high as 20% in infected pregnant women. The causative agent of hepatitis E , hepatitis E virus(HEV), is a single-stranded positive-sense RNA virus without an envelope. HEV is generally transmitted by the fecal-oral route. The genomic RNA of HEV is about 7.5kb and contains three open reading frames(ORFs). ORF1 is predicted to encode viral nonstructural proteins, ORF2encodes the putative capsid protein, and ORF3 encodes a cytoskeleton-associated phosphoprotein.However Sporadic cases of clinical hepatitis E not only occur in these countries but also occur uncommonly in patients with no know epidemiological exposure to HEV in industrialized countries. The source of infection in industrialized countries.is unknow but it has been hypothesized that animals might serve as a reservoir for HEV in both settings. The recent identification of swine HEV in U.S pigs and the demonstration of its ability to infect across species have lent credence to this hypothesis.. In order to learn the situation in Chinese, we start this experiment on HEV.This research adopt ELISA method to invest the situation in Chinese some provinces, of pigs if it is infected hepatitis E. We have gathered 1706 swine serum from the 48 pig farms of 18 nation-wide province city autonomous regions, These swine have different month age which have 521 pigs below 2 mouths age and have 611 pigs between 2-6 months age and have 574 pigs about 6 month age . The result show that in which, 1126 copies of serum is HEV antibody positive. Average positive rate is as high as 66% . all 48 pig farms of was detected, and the result show that only one pig farm have no HEV antibody, there is 6 pig farms which is antibody positive rates below 20% there is 13 pig farms which is antibody positive rates between 20%-60%; there is 16 pig farms which is antibody positive rates between 60%-90%; there is 12 pig farms which is antibody positive rates above 90%. At the same time the antibody positive rate of HEV make change along with different month . The swine of 6 mouth age of antibody positive rate is the highest and it is 90.47%, secondly the swine of 2-6 mouth age of antibody positive rate is high and it is 70.05% . The swine of under 2 mouth age of antibody positive rate is low and it is only 33.78%. These results show the antibody positive rate of pig crowd go up possibility along with month make increase. At the same time, this experiment have gathered serum and fecal from the pig farm which antibody positive rate is higher certain. We handle after them and, draw RNA, from them.The result of transcribe used in nested PCR to increase and clone. As a result we have cloned HEV ORF2 N ends fight decision mainly the partial gene segments of district which is 348 bp. This section gene compare with have published Indian in HEV gene type , I Mexican in HEV gene type II and HEV gene type III in American HEV us-1 , one Chinese persons HEV and one Japanese HEV as well as place the Taiwan of gene type IV gene sequence et al . The result of sequence analysis show this section nucleotide acid sequenc is smililarity with the Taiwan of gene type IV which is 86.4% and is divergence from Mexican in gene type II which is 73.0%; this section amino sequence is Smililarity with one Chinese person highest, which is 99.1%; and Smililarity with with Indian of gene typeIminimum which is also 94%. We can know from the result that the change level of nucleotide acid is great , but amino acid is less. This can explain this section gene change greater, however amino acid relatively conservative. At the same time, this section gene have cloned PET-30 a(+) successfully for 348 bp purpose gene segments, and i...
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