ABSTRACT
Objective To investigate the prevalence of anti-hepatitis E virus (HEV) and genotypes of hepatitis E virus in 8 species of animals including swine, cattle, sheep, horse, donkey, dog, chicken and duck in the suburb of Beijing. Methods Serum samples were collected from the 8 species of animals, and fecal samples of younger swine were collected from 2 stock farms. Anti-HEV was detected by Double Antigen Sandwich Assay. HEV RNA from fecal samples was detected by a reverse transcription nested polymerase chain reaction (RT-nPCR). Parts of the PCR products were cloned and sequenced. The swine HEV sequences were analyzed genetically. Results The positive rates of anti-HEV in serum specimens of swine, cattle, horse, donkey, sheep, dog, duck and chicken were 80.43%(481/598), 15.02%(52/346), 14.29%(40/280) ,0(0/26) ,9.88%(33/334), 0(0/ 21) ,3.03% (7/231) and 2.53%(8/316), respectively. The anti-HEV prevalence of adult swine(≥6 months)and younger swine(≤3 months)were 87.86%(369/420)and 62.92%(112/178)respectively. 74 of 111 (66.67% ) pig faces were positive for HEV RNA. Sequence analysis on these positive samples showed that there were 6 groups of HEV designated as bjsw1, bjsw2, bjsw3, bjsw4, bjsw5 and bjsw6. The 6 strains of HEV shared 94.5%-99.6% sequence identity of partial HEV ORF2 nucleotide with each other. The identities of HEV ORF2 nucleotide sequences between the 6 strains and genotype 1, 2, 3 and 4 were 75.6%-78.6% , 75.6%-76.2%, 77.1%-80.7% and 83.7%-94.5%, respectively. The sequence identity between the 6 strains and human HEV genotype 4d was 90.0%-94.5% . Conclusion HEV infection was seen in swine, cattle, horse, sheep, duck and chicken in the suburbs of Beijing. The anti-HEV positive rate appeared the highest in swine and the lowest in dog and donkey. The six strains of HEV isolated from younger swine belonged to genotype 4d.
ABSTRACT
Objective To study the killing effect of focused ultrasound activated-hematoporphyrin on H-22 and its optimum exposure time.Methods The distribution of hematoporphyrin in H-22 cells was measured by a fluorescence photometer,the uhrastructure changes were evaluated at different time with a scanning electron micro- scope after treatment with focused ultrasound at the frequency of 1.43 MHz and intensity of 1.0 W/cm~2, 2.0 W/cm~2,3.0 W/cm~2,respectively,in combination with HpD.Results The concentration of HpD in the H-22 cells reached its peak after being added to H-22 tumor cells for 45 minutes,which will produce the hest anti-tumor effect when activated by ultrasound.Morphological observation showed that HpD alone had a slight influence on H-22 cells;ULtrasound alone showed an anti-tumor effect on tumor cells,which was dosage-dependent.Ultrasound dia- thermy in combination with HpD has more effective in terms of its antitumor effect when compared with uhrasound dia- thermy alone.Conclusion The killing effect on H-22 tumor cells of sonodynamic treatment was dependent on the intensity of uhrasound and the content of HpD in the cells,as well as on the time of action of both uhrasound and HpD.
ABSTRACT
Objective The aim of this study was to investigate the effect of ultrasonically activated hematoporphyrin on ultrastructure of ehrlich ascites tumor(EAT) cells and to evaluate the potential mechanism of action inducing this cytotoxicity. Methods EAT cells in vitro were exposed to ultrasound at 2