Medical science is the science which closely combines scientific knowledge with humanistic spirit. Becausemodern science and technology have been more and more applied in medical research and practice, the medical sciencehas been developed rapidly. But medical science calls us to concern more about medical humanistic spirit, so how wecombine medical scientific knowledge with humanistic spirit is a very important topic in our medical university education.[

Objective To establish a clinical test assay for detecting common respiratory viruses and enteroviruses (EV) by using mixed cultured Madin-Darby canine kidney cells (MDCK), human epidermoid cancer cells (Hep-2) and African green monkey kidney cells (Vero) to isolate common respiratory viruses and enteroviruses. Methods Throat swabs with influenza A and B viruses,adenovirus and EV71 were incubated with mixed cultured MDCK, Hep-2 and Vero in a single vial to observe the presence of cytopathic effects. Polymerase chain reaction (PCR), reverse transcription (RT)-PCR and monoclonal antibody-based immunofluorescene assay were also used for confirmatory test. Results The sensitive cell lines developed obvious cytopathic effects to the corresponding viruses, which were confirmed by the specific green particles observed by immunofluorescence assay and specific target PCR segments. Conclusions The shell-vial of mixed cells can simultaneously isolate different common respiratory viruses and EV. The isolated pathogens can be further confirmed by antigen test and PCR. This assay may improve the diagnosis of clinical viral diseases.

Objective To sequence and analyze the full-length genome of one HEV strain,W2-1 isolated from a sporadic hepatitis E patient hospitalized in 1999 in Xinjiang,China.Methods Nested RT-PCR assays with 4 sets primers were used to amplify the entire genome.The PCR products were purified and sequenced.The full-length genome was acquired by assembling the fragmental sequences using the DNAstar 5.01 software.The genome of W2-1 was analyzed by comparing with the reference HEVs from GenBank.Results The complete genome of W2-1 is 7212 nt in length,including three open reading frames (ORF1-3) with 5079,1980 and 345 nt respectively,27 nt 5'UTR and 83 nt 3'UTR,and a 3' poly A tail.Phylogenetic analysis based on full-length genome showed that W2-1 belonged to genotype 1,subtype 1b.W2-1 had high homology with the HEV strains isolated in the large hepatitis E epidemic in Xinjiang in 1987-1989,sharing 97.2％-98.5％ nucleotide identity in the full length genome.W2-1 also showed high homology with 1b strains isolated in China after 2000,with 97.6％-99.2％ nucleotide identity.The specific amino acid sites in ORF1-3 proteins that distinct between genotype 1 HEV and the potential zoonotic strains did not change in W2-1.Conclusion W2-1 belongs to subtype 1b.The study indicates subtype 1b HEV has been circulating in China in a long period after hepatitis E outbreak in Xinjiang in 1986-1989.The amino acids of ORF1-3 of subtype 1b are conserved.

Objective:Recent studies have shown that in contrast to decrease in distal gastric adenocarcinoma (DGA), incidence of adenocarcinoma of the esophagogastric junction (AEG) has increased noticeably in numerous counties. However, the reasons remain unclear. This study evaluated the possible differences in the expression of KLF4, SP1, and Cyclin D1 in AEG and DGA, and explored the potential carcinogenesis of AEG. Methods:Immunohistochemistry was performed on paraffin-embedded tissues to evaluate the pu-tative differences in the expressions of KLF4, SP1, and Cyclin D1 at protein level between AEG (n=58) and DGA (n=47). The patholog-ical significance of these markers between the two groups was also compared and analyzed. Results:The percentage of positive KLF4 expression was significantly lower in DGA than in AEG (P<0.05). Lower KLF4 expression was found both in well-or moderately dif-ferentiated cases and in poorly differentiated cases with DGA compared with their AEG counterparts (P<0.05). However, positive stain-ing for SP1 was significantly higher in DGA (P<0.05). No significant difference was found in the expression of Cyclin D1 between the two groups. Further analysis showed that in DGA, the positive expression of KLF4, SP1, and Cyclin D1 were significantly correlated with lymph node metastasis. In AEG, only Cyclin D1 expression was correlated with lymph node metastasis (P<0.05). No correlation was found among the expression of KLF4, SP1, and Cyclin D1 in AEG. In DGA, KLF4 was inversely correlated with SP1 and Cyclin D1 (r=-0.334 and r=-0.341, respectively, P<0.05), and SP1 was positively correlated with Cyclin D1 expression (r=0.340, P<0.05).Conclusion:Different expression patterns and clinicopathological significance of KLF4, SP1, and Cyclin D1 were observed between AEG and DGA, suggesting the putative difference in the carcinogenesis and progression of AEG and DGA.

Objective To evaluate the trimester specific reference ranges and dynamic changes of thyroid functional indicators during gestation of healthy pregnant women.Methods According to the selection criteria,139 cases were selected as the normal pregnant population to establish a self-sequential longitudinal reference range.We collected samples eight times in every case throughout the gestation(including the 8th,12th,16th,20th,28th,36th week of prenatal,the 3rd and the 6th month postpartum) and detected the indicators of thyroid funciton.Meanwhile,301 healthy non-pregnant women of childbearing age were selected as the control group.Results The median of TSH was lowest in the first trimester,and then was increased in the second and third trimesters.The reference ranges of TSH were 0.20-4.01 mIU/L,0.43-3.97 mIU/L,and 0.57-3.96 mIU/L in the above trimesters.The free thyroxine (FT4) level from the 12th week of gestation to the 6th month of postpartum was gradually decreased and was lower than the non-pregnant level.The total thyroxine (TT4) was significantly increased at the 12th week of gestation and thereafter it was stable and returned to normal after childbirth.The free triiodothyronine(FT3) was gradually declined from the 12th week to the 28th week and returned to normal postpartum.Total triiodothyronine(TT3) was significantly increased at the 12th week and thereafter was stable,and returned to normal after childbirth.There was a significant negative correlation between TSH and FT4 in the first trimester(P＜0.01).There was no correlation between TSH and TT4 during the whole gestation.There were positive correlations between FT4 and TT4,FT3 and TT3 since the 12th week of gestation (P ＜ 0.01).Conclusions The gestational specific reference range of TSH based on the selfsequential longitudinal study was narrow,however,the upper limit was still higher than that recommended in foreign guidelines.

Objective To study the prevalence and genotype of human parvovirus B19 virus among blood products and plasma pools in China. Methods B19 DNA derived from 16 lots of factor Ⅷ concentrate produced by 4 manufactures and 10 lots of plasma pools were detected by nested PCR. Phylogenetic comparison of the partial B19 sequences obtained from positive samples were performed by direct sequencing. Results Twelve of sixteen lots of factor Ⅷ concentrate and all of ten lots of plasma pools were contaminated by B19 DNA. By comparing the partial B19 sequences,all the isolated viruses were genotype Ⅰ and their nucleotides were high conserved with homology of 98. 3%-100%. Conclusion B19 genotype Ⅰ DNA has been detected in high prevalence in factor Ⅷ concentrate and plasma pools. The genetic diversities were shown to be very low.

Objective To investigate the clinical significance of detection of hepatitis E virus (HEV) RNA in sera from patients with acute hepatitis E using real-time reverse transcription (RT)-PCR to detect hepatitis E virus RNA in sera from patients with acute hepatitis E.Methods A real-time RT-PCR assay, which can amplifies and detect the conserved region on ORF3, was used in this study. 434 outpatients and hospitalized patients with acute HEV infection was enrolled into this study.Simultaneously,the serum samples from 40 patients with HAV infection, 100 patients with HBV infection and 110 healthy blood donors were collected as the control The real-time RT-PCR was performed to detect HEV RNA in all these sera.Results 232 sera (53.5%) were positive for HEV RNA by real-time RT-PCR and all of the control were negative.The results of real-time RT-PCR and anti-HEV IgM (ELISA) were concordant in 67.1% samples.There was significant difference between the two methods ( Kappa = 0.308, P = 0.000 ).The first serum sample from five serum samples of the patients was positive for HEV RNA and negative for anti-HEV IgM.Follow-up studies showed all the five sera samples were positive for anti-HEV IgM.HEV RNA in serum could be detected between 2 and 10 days.Conclusions The real-time fluorescent RT-PCR method has high specificity, and can be applied to the qualitative detection of the serum with genotypes Ⅰ and Ⅳ of hepatitis E virus.Its clinical use can improve the early diagnosis of HEV.

Objective To study the influence of site-directed deglycosylation of the HIV-1 envelope (Env) on its immunogenicity and assembly of functional pseudovirus. Methods Site-directed deglycosylation were performed using cycling mutagenesis and selection of mutants with DpnⅠ. Single-cycle infection assay was employed to analyze the effect of the mutations on the ability of functional pseudovirus assembly. The influence of deglycosylations on the immunodeficiency of Env was evaluated using pseudovirusbased neutralization assay and ELISPOT assay. Results Mutant N197Q induced higher neutralization activities for both pseudoviruses, but lower Env-specific T-cell response. And N197Q rendered the Env to lose the ability of functional pseudovirus assembly. Mutant G2 induced higher neutralization activities for pseudovirus 74-2 but lower for pseudovirus Wt, and had almost no influence on Env-specific T-cell response and functional pseudovirus forming. Conclusion The site-directed deglycosylation of the HIV-1 Env affects the pseudovirus forming and its immunogenicity.

Objective To compare cellular immune responses in mice elicited by Chinese different AIDS candidate vaccines.Methods According to their different immunization procedures,BALB/c mice were immunized with 6 AIDS candidate vaccines,separately.Spleen cells were isolated for the detection of cellular immune response to HIV-specific peptides using enzyme-linked immunosorbent spot(ELISPOT)assay and intracellular cytokine staining(ICS)method.Results AIDS vaccines were evaluated by using potential T-cell epitopes(PTE)Gag,Env and Pol peptides pool and ELISPOT.The positive conversion rates for cellular immune response of 1#-6# vaccines fluctuated from 70% to 100%.The vaccine-induced cellular immune responses to specific peptides pool are different not only in magnitude but also in breadth.The Th1type cytokines,IFN-γand IL-2,were detected with ELISPOT in 1# and 2# vaccines.The productions of IFN-γand IL-2 induced by both of the two vaccines showed a moderate correlation(r1 =0.62,P1 ＜0.01 ;r2=0.79,P2 ＜ 0.01).The positive conversion rate of IFN-γ secreting cells of 1 # vaccine was 66.7%(10/15)mice detected with both ELISPOT and ICS.And the results tested by ELISPOT and ICS showed moderate correlation(r = 0.55,P ＜ 0.05).Conclusion The magnitude and breadth of cellular immune responses induced by different AIDS candidate vaccines are different.Being induced by different AIDS candidate vaccines,the IFN-γand other Th1 type cytokines detected by ELISPOT or ICS could be used to evaluate the cellular immune responses in mice.

Objective To analyze the practicability of using ELISA kit for the detection of hepati-tis E virus antigen ( HEV-Ag) in plasma donations and Biomex HEV seroconversion panels. Methods The HEV-Ag positive samples were screened out from 36 340 donated blood plasma samples. Real-time fluores-cent PCR was performed for the detection of HEV RNA in HEV-Ag positive samples. The open reading frame 2 (ORF2) in HEV RNA was amplified by nested RT-PCR and the amplified products were confirmed by sequencing analysis. Phylogenetic tree was constructed for HEV genotyping. Five Biomex HEV serocon-version panels were used in this study for the detection of HEV-Ag, anti-HEV antibody and HEV RNA as well as the correlation analysis between HEV-Ag and HEV RNA. Results Twenty-six out of 36 340 plasma samples (0. 07%) were positive for HEV-Ag. Of the 26 samples, 25 samples were positive for HEV RNA as indicated by the results of nested RT-PCR and 23 positive samples were confirmed by sequencing analysis. The positive rate of HEV RNA in blood plasma donators was 1 ∶ 1 580 (0. 06%). There were 17 samples of genotype 1 (74%) and 6 samples of genotype 4 (26%) according to the phylogenetic tree analysis. All of the HEV-Ag positive samples were also positive for HEV RNA as indicated by the analysis of Biomex sero-conversion panels. HEV-Ag was consistent with the peak of the HEV RNA concentration. Conclusion A close relationship between HEV-Ag and HEV RNA was observed. HEV-Ag screening could be used as a measure to reduce the risk of HEV transmission by blood transfusion.