Objective:To gain insight into the mechanism responsible for clearance of natural hepa DNA virus infections.Methods:A group of seven 2～3 month old ducks were infected intravenously with 10～20 ml DHBV positive serum containing 5?10 7 genomes/ml.Following inoculation,ducks were bled at weekly intervals to obtain serum samples for analysis of DHBV DNA and DHBsAg and anti DHBV antibodies.Peripheral blood mononuclear cells were collected at 10,35 days postinoculation(p.i) and used to conduct antigen specific blastogenesis assay.Liver samples were obtained at 5,30,60 days p.i for analysis of DHBV DNA and surface antigens and liver histology.Results:Infection of all 7 animals with approximately 5?10 8～1?10 9 DHBV genomes led to a transient viremia after an incubation period of 1 to 2 weeks.Liver samples contained multiple copies of all of the expected species of DHBV DNA replicative intermediates,including DHBV cccDNA during the peak of viremic phase.Further analysis showed that the absence of a prolonged viremia could be explained by immediate antigen specific blastogenesis and high titer of antibody response.Meanwhile,there was no obvious evidence of liver cell injury during transient DHBV infection.Conclusion:These results demonstrate that noncytopathic antiviral mechanisms make a role in hepa DNA virus clearance.

Objective　we studied the effect of the Purine mucleoside Valaciclovir on anti-duck hepatitis virus(DHBV) in vivo to provide an experimental basis for clinical treatment of patients with hepatitisB.Methods　The Chongqing duck hepatitis B virus model was treated with Valaciclovir once a day for a month at the doses of 50mg.kg－1、100mg.kg-1、200mg.kg－1of body weight per day. Serum DHBV DNA was detected four times in the course of the treatment,ALT and AST in serum and DHBV DNA in liver were detected simultaneously.Results　Valaciclovir could signsificantly lower the serum DHBV DNA level. Serum ALT of several ducks in serum rose slightly during the treatment,but became normal after 1 week stopping Valaciclovir. Examination of DHBV DNA in liver with Southern Blot indicated Valaciclovir could inhibit DHBV DNA replication,but could not completely eliminate DHBV SC DNA.Conclusion　The study confirms the safety and potent antihepaticviral activity of Valaciclovir in vivo.

Objective To investigate the dynamics of the level of S100 in cerebrum, brainstem, and serum following the diffuse brain injury in rats and provide the experimental evidences for estimating injury time. Methods ELISA was used to determine whether S100 protein is changed after diffuse brain injury in rats. Forty rats were sacrificed at 0.5 hour, 2 hours, 4 hours, 12 hours, 24 hours, 3 d and 7 d after diffuse brain injury and normal rats as control. Results The level of S100 in cerebrum, brainstem, and serum increased, followed by a decrease, and then further increased. The level of S100 could be detected to increase at 30 minutes and reached the peak at 4 hours after DBI. The level decreased gradually to the normal at 1d and till 3 d formed the second peak. The level returned to the normal at 7d following injury again. In the postmortem injury groups, there were no significant changes compared to the control group. Conclusion The present study showed that the time-dependent expression of S100 is obvious following diffuse brain injury in rats and suggested that S100 will be a suitable marker for diffuse brain injury age determination.

OBJECTIVETo establish a sensitive and specific technique for detecting HBV DNA in serum using HBV DNA probe labeled directly by alkaline phosphatase (AlkPhos Direc probe).

METHODSThe probe that purified HBV DNA sequence was labeled directly by alkaline phosphatase and chemiluminescent substrate CDP-star for AP was used in the hybridization assay. HBV DNA was detected by autoradiography on the film. The test compared the chemiluminescen dot blot hybridization assay for 80 samples with digoxigenin-labeled HBV DNA probe detective method. The correlation of 70 samples test results between fluorescent quantitative HBV DNA PCR method and dot blot hybridization assay by AlkPhos Direc probe was analysed.

RESULTSThe sensitivity of the probe labeled directly by alkaline phosphatase was 10pg at least. The coincidence was 100% compared with digoxigenin-labeled HBV DNA probe detection. A correlation coefficient of HBV DNA quantitative results between fluorescent quantitative HBV DNA PCR (QPCR) method and dot blot hybridization assay by AlkPhos Direc probe was 0.98 (P<0.01).

CONCLUSIONSThe method detecting HBV DNA in serum by HBV DNA AlkPhos Direc probe is sensitive and specific. The results between two methods with AlkPhos Direc and digoxigenin-labeled HBV DNA probe are coincident completely. The correlation of HBV DNA quantitative results between fluorescent QPCR method and dot blot hybridization assay by AlkPhos Direc probe is satisfactory.

Alkaline Phosphatase ; chemistry ; metabolism ; Animals ; DNA Probes ; chemistry ; genetics ; DNA, Viral ; blood ; genetics ; Hepatitis B ; blood ; diagnosis ; virology ; Hepatitis B virus ; genetics ; Humans ; Molecular Diagnostic Techniques ; methods ; standards ; Polymerase Chain Reaction ; methods ; Sensitivity and Specificity

Objective To test the antimicrobial susceptibility of Staphylococcus aureus from children with impetigo,and to assess the differences in randomly amplified polymorphic DNA profiles between sensitive and resistant Staphylococcus aureus strains.Methods Secretion specimens were obtained from the impetiginous lesions of 178 children,and subjected to bacterial culture.The susceptibility of 162 Staphylococcus aureus isolates against 21 antibiotics was tested.Randomly amplified polymorphic DNA PCR(RAPD-PCR)was performed to characterize the genotype of Staphylococcus aureus.Results Totally,180 bacterial strains were isolated from 178 children with impetigo in Chengdu,including 162(90.00％)Staphylococcus aureus strains.Of the 162 Staphylococcus aureus strains,148 were methicillin sensitive Staphylococcus aureus(MSSA),14 methicillin resistant Staphylococcus aureus(MRSA).The most active antibiotic was minocycline,followed by teicoplanin,quinupristin,vancomycin and nitrofurantoin,while the resistance rate to penicillin was highest,followed by that to erythromycin,clindamycin,compound sulfamethoxazole and tetracycline.All the Staphylococcus aureus isolates were sensitive to fusidic acid,nitrofurantoin,vancomycin,minocycline and teicoplanin.According to RAPD-PCR,the 162 Staphylococcus aureus strains were divided into 8 genotypes,with the three most prevalent genotypes being Ⅲ(31.48％),Ⅱ(26.54％)and Ⅵ(25.93％),which accounted for 65.43％(106/162)in all the strains.The 148 MSSA strains fell into 8 genotypes,with genotype Ⅲ(50 strains,33.78％),Ⅵ(39 strains,26.35％)and Ⅱ(33 strains,22.30％)being the most prevalent genotypes;the 14 MRSA strains fell into 3 genotypes,i.e.,genotype Ⅱ(10 strains,71.43％),Ⅵ(3 strains,21.43％),and Ⅲ(1 strain,7.14％).Conclusions Staphylococcus aureus is the most prevalent pathogenic bacteria in children with impetigo in Chengdu area,which is highly sensitive to minocycline,teicoplanin and quinupristin,and falls into 8 genotypes according to RAPD-PCR with genotype Ⅲ being the most common genotype.

The historical evolution， fermentation technology and key links of Sojae Semen Praeparatum （SSP） were sorted out by consulting ancient books and modern literature， and the influencing factors and control methods of quality were analyzed and summarized in order to provide reference for the quality control of SSP. After analysis， it was found that in the fermentation process of SSP， fermentation strains， miscellaneous bacteria， temperature and humidity were all important factors affecting the quality of SSP. The condition control of "post fermentation" process has been paid more attention to in the past dynasties. In addition， the delicious SSP recognized in ancient times should be made from mold fermentation， and the breeding and application of fermented mold may be the key point to solve the quality problem of SSP. Therefore， based on the evaluation indexes of SSP in the past dynasties， it is of great significance to study and optimize the technological conditions such as strain， temperature and humidity in depth to improve the quality of SSP.