AIM: To investigate the mechanism by which human amnion induced mouse embryonic stem (ES) cells to differentiate into epidermal like cells. METHODS: ES-BALB/c cells were cocultured with human amnion in transwells for 4-5 days, and those cultured alone without amnion were taken as control group. The morphological differentiation were observed. The committed differentiation of ES cells into epidermal like cells were detected by integrin-?_1, CK19, CK15 and involucrin immunohistochemistry, respectively. RESULTS: After 4-5 days of coculture, ES cells differentiated into single layer of epidermal like cells, fitted tightly, with polyhedral in shape. The immunohistochemical staining results showed that, most of the cells were integin-?_1 positive, only a few cells were CK19 and CK15 positively stained. Most of the cells in control group died, the survived ones were different in morphological shapes, and no integrin-?_1, CK19 and CK15 positive cells were found. CONCLUSION: Soluble substances secreted by human amnion may play an important role in inducing the differentiation of mouse ES cells into epidermal like cells. [

Objective To investigate the differentiation potenitial of ES cell derived epidermal like stem cells,to lay a base for the study of their differentiation mechanism,as well as seek new source to provide seed cells for skin engineering. Methods Mouse ES cells labeled or unlabeled by Hoechst 33342 were cocultrued with human amnion for 4 days.The epidermal like stem cell clones formed on the surface of amnion were digested with trypsin and transplanted into hypodermis of nude mice for 10,20 and 45 days,then the differentiation pattern of the donor cells were observed and estimated with morphological and immunohistochemical method. Results The grafts may differentiate into tubular or follicular like structures lined with simple or stratified epithelial like cells which expressed ? 1 integin,CK19,CK15,PK involucrin and CEA respectively after 10 to 30 days of transplantation.Keratinized stratified squamous epithelium,sebaceous gland like,sweat gland like and hair follicle like structures were observed after 45 days ofter transplantation.Conclusion ES cell derived epidermal like cells might have differentation potential to diffreentiate into keratinized stratified squamous epithelium,sebaceous like,sweat gland like and hair follicle like structures.

Objective To investigate water treatment technology and pollution status of Giardia lamblia and Cryptosporidium parvum in resource water and finished water of the centralized water supply enterprises in Shenzhen,and to provide scientific basis for waterborn infectious disease control.Methods Field hygiene assessment were conducted on the resource water and water treatment technology of 19 water supply enterprises during May to July,2008.One water sample was collected from resource water and finished water in each centralized water supply enterprise respectively,and was detected for Giardia lamblia and Cryptosporidium parvum.Results The routine traditional water treatment technology including coagulation deposition,quartz sand filtration and chlorine disinfection was applied in all of the 19 centralized water supply enterprises.Giardia lamblia and Cryptosporidium parvum were not found in samples from the source water and finished water.Conclusion The centralized water supply system in Shenzhen isn't polluted by Giardia lamblia and Cryptosporidium parvum.

Objective To explore the efficacy and protective mechanism of calpain, a calcium activated neutral proteinase as a vaccine candidate molecule. Methods Anti calpain sera were prepared by immunized BALB/c mice with recombinant calpain. Anti calpain sera, schistosomula of Schistosoma japonicum , and mouse eosinophils were incubated at 37 ?C , 5% CO 2 for 48 hours, and the adherence of eosinophils to schistosomula and its schistosomulacidal efficacy were observed. Results Mice immunized with recombinant calpain produced a high level IgG antibodies specific to the antigen immunized. Immunoblotting analysis showed murine anti recombinant calpain sera bound specifically to recombinant calpain. Ninety six percent of schistosomula were surrounded by cells when incubated with mouse eosinophils, and a significant number of dead schistosomula was observed at 48 hours when incubated with mouse serum and eosinophils as compared with control serum and eosinophils ( P

The significant differences in prevalence rate of essential hypertension among the races in Xinjiang, i.e. in Kazakh, Han, and Uighur had been shown in 1979 screening. They were 6.6%, 3.5% and 2.6% respectively.The present investigation shows that some dietary constituents as well as the nutritional imbalance was involved in the causal effect in the development of hypertension.Three race people living in three quite different areas (geographic, climatic environmental conditions etc,) were investigated in April to July 1981. Blood pressures of 9,313 persons were measured. The dietary pattern and staple food items were studied for 491 persons within 69 families.The findings suggested that: l)the prevalence rate of hypertension was identical to the previous screening, 2) there was a positive correlation between the high consumption of protien (r= 0.974), fat(r = 0.622) and the prevalence rate of this disease, but a negative correlation in vitamin C intake (r = -0.620).The excessive intake of salt was accounted as a risk factor for poss- ible association with this disease only in Kazakh people who were living in various areas.

Objective To compare the expression level of calpain and calpastatin mRNA in rheumatoid arthritis (RA) and osteoarthritis (OA) synovial tissues (ST) and analyze the antigen epitopes of human calpastatin recognized by RA sera.Methods Total RNA of three RA and two OA patients was isolated from ST and expression levels of calpain and calpastatin mRNA were detected by reverse transcription polymerase chain reaction (RT PCR).According to hydrophilicity of human calpastatin (Accession,U 31346), overlapping oligopeptides were synthesized by auto spot Robot in N terminal (L domain) and C terminal (Ⅳ domain) of calpastatin.The epitopes of synthesized peptides were analyzed by RA sera using dot ELISA.Results mRNA expression of calpain showed higher than that of calpastatin in both OA and RA.Meanwhile,the mRNA expression level of calpain increased in RA more than that in OA.Three antigen epitopes of human calpastatin (with the sequence DKDLDDALD,DTIPPEYRH and QDPIDALSG) were identified by RA sera,while control sera failed to react with synthetic peptides.Conclusion The calpain calpastatin system may participate in pathogenic mechanism of RA,and the calpastatin may be a target for autoantibody of RA,which implies that it is not only possible to treat RA patients with synthetic peptide of human calpastatin,as a chemotherapeutant,but also a materials for immunodiagnosis of RA.

Objective To investigate the condition which can induce mouse ES cells to differentiate into epidermal-like stem cells for the clinical application of ES cells-derived epidermal-like stem cells and the research on the mechanism of committed differentiation of ES cells. Methods Coculture mouse ES cells with human amnion for 3-4 days, and the committed differentiation were detected by flow cytometry and immunohistochemistry. In experimental group 1, amnion was pasted covering the whole bottom of the wells, with the epithelial surface upward, and in group 2 covering the half bottom. No amnion was used in control. Results After 3-4 days of co-culture, epidermal-like stem cell clones were formed on the epithelial surface of amnion in group 1 and group 2, and expressed high levels of integrin-? 1, CK19 and CK15. The percentages of integrin-? 1, CK19 and CK15 positive cells counted in group 1 by flow cytometry were 89.2%, 86.8% and 71.2% respectively, versus the control group of 8.4%,9.6% and 11.8%, the differences were significant in all the three indices (Z tests P

Objective To investigate the effect of recombinant human interferon α-2b on influenza virus in vitro.Methods Influenza A virus subtype H1N1 and influenza B/Y virus were inoculated into Vero cells and different concentrations of interferon α-2b and oseltamivir were added.Numbers of virus plaques were observed and calculated,and quantitative RT-PCR were used to assess the inhibitory effect of interferon α-2b and oseltamivir in vitro.The nuclear export of viral ribonucleoprotein (RNP) complexes were monitored under fluorescence microscope.Results Virus plaque test showed that influenza A viruses subtype H1N1 were significantly inhibited when 10 μg/μL interferon α-2b and 10 μg/μL oseltamivir were added,and the numbers of plaques were 7.5 × 108 and 15 × 108 PFU/mL,respectively;the inhibitory effect of oseltamivir was better than that of interferon α-2b.Influenza B/Y viruses were also inhibited when 10 μg/μL interferon α-2b and 10 μg/μL oseltamivir were added,and the numbers of plaques were 1.1 × 108 and 1.5 × 108 PFU/mL,respectively.Quantitative RT-PCR results showed that the cycle threshold (CT) values of influenza A virus subtype H1N1 and influenza B/Y virus were much higher when 10 μmol/L interferon α-2b and 10 μmol/L oseltamivir were added.CT values of influenza A virus subtype H1N1 were 16,26 and 35 before and after inferferon α-2b and oseltamivir were added.CT values of influenza B/Y virus were 18,27 and 31 before and after interferon α-2b and oseltamivir were added.Reduction in the nuclear export of viral RNP in influenza A virus subtype H1N1-infected Vero cells was also observed when 10 μmol/L interferon α-2b were added.Conclusion Interferon α-2b has significantly inhibitory effect on both influenza A virus subtype H1N1 and influenza B/Y virus in vitro.

Objective To analyze the VP1-VP4 genetic region of enterovirus 71 ( EV71 ) strains isolated from children with severe or mild hand, foot and mouth disease ( HFMD) in Shenzhen in 2012. Methods EV71 strains were isolated from five children with mild HFMD and five children with severe HFMD in Shenzhen in 2012.Reverse transcription-polymerase chain reaction ( RT-PCR) method was used to amplify the sequence of VP1-VP4 genes of EV71 strains.The sequences of the amplified products were analyzed by comparing with those of the EV71 reference strains ( A, B and C genotypes) published in Gen-Bank using nucleotide alignment, amino acid alignment and phylogenetic tree analysis.Results The homo-geneity between the EV71 strains isolated from severe and mild cases was 95.1%-98.2% in nucleotides and 99.2%-100% in amino acids.The VP1-VP4 nucleotide sequences of 5 strains isolated from severe cases and 5 strains from mild cases in Shenzhen shared 87.9%-97.8% homologies in nucleotides and 97.3%-99.9% homologies in amino acids with the genotype C EV71 reference strain.The EV71 strains isolated from children in Shenzhen were highly similar with the EV71 strain (FJ439769) isolated in Fuyang in 2008 and the one isolated in Jingdezhen in 2011 (JQ806378, C4a subtype) in nucleotide sequences.Mutations at the residue 31 in the VP1 region ( N→D ) were detected in 3 strains isolated from children with severe HFMD.Conclusion All of the 10 EV71 strains isolated in Shenzhen in 2012 belonged to the sub-genotype C4a.The mutation ( aa31 N→D) in the VP1 region of EV71 might be related to the different clinical mani-festations of HFMD cases in Shenzhen area.