Objective To study the ability of adhesion, proliferation and differentiation of human adipose mesenchymal stern cells,which were cultured in PLGA,and thus to provide a basis for their in vivo implantation.Methods PLA was mixed with PGA in a ratio of 1∶ 1,and PLGA was obtained by insert moldling with organic solvents.In vitro, human adipose mesenchymal stem cells were adhered to PLGA.The attachment and the proliferation of human adipose mesenchymal stem cells in PLGA were analysed by scanning electron microscope,and the morphological change of the cells was investigated before and after induction.Results Human adipose mesenchymal stem cells were able to attach, proliferate and secrete extracellular matrix in porous PLGA (pore size:100～400 pm) with porosity of 85 %, and to differentiate into round lipoblast-like cells under the induction of adipose medium.After 14 days, the particulate of PLGA was overlaid by extracellular matrix .Conclusion Human adipose mesenchymal stem cells have the capacity to adhere to PLGA and proliferate, indicating that PLGA can be used as a carrier for human adipose mesenchymal stem cells in adipose tissue engineering.

Tethered cord syndrome is a severe and congenital disease. Resecting the diseased ilium terminal(FT), eystis, lipoma is the main treatment for the disease, relieving the injury to the eonus medullaris. Why the FT is diseased and thickened? Is it necessary to eut internal FT or external FT? What is the injury mechanism of the low-positional or normal positional oonus medullaris? To study the component and structure of the conus medullaris and FT may give definite answers.

Objective To evaluate the safety of the levels of fluoride,arsenic and lead in toothpaste and the microbiological index of the toothpaste saled in Tianjin. Methods 60 tubes of toothpaste were sampled from the department stores and shops in Tianjin. The toothpaste samples included 14 tubes of commen toothpaste,18 tubes of medicated toothpaste,28 tubes of toothpaste blended with fluoride. Among 28 tubes of fluoride-adding toothpaste,6 tubes were specially used for children,19 tubes were domestic products for adults,3 tubes were imported for adults. All of the domestic toothpaste sampled were made in more than 10 cities and privinces such as: Tianjin,Beijing,Shanghai,Guangdong,etc. The levels of fluoride in toothpaste were determined by ion selective electrode,arsenic and lead were determined by inductively coupled plasma emission spectroscopy,the microbiological indexes were determined based on GB8372-1995 (toothpaste?雪. Results The contentes of soluble fluoride were 539-877 mg/kg for 5 tubes of fluoride-adding toothpaste used for children, 1 582-1 697 mg/kg for 3 tubes of domestic fluoride-adding toothpaste used for adults. The content of lead in an tubes of imported toothpaste was as high as 43.09 mg/kg,2.9 time the value of the national standard. The total count of bacteria,the count of fecal coliform,Paeruginosa,Staph aureus in 52 tubes of toothpaste sampled met the requirement of the related national standards. Conclusion The sanitary quality of 60 tubes of toothpaste sampled for this study saled in Tianjin was qualified in general,but very few had the sanitary problems in the aspects of fluoride excess in domestic fluoride-adding toothpaste and lead excess in imported toothpaste.

Objective To study the estrogenic effect of organic extracts of effluent samples from different treatment stages in Tianjin reclaimed water treatment plant. Methods Reverse phase C-18 solid-phase extraction (RP-C18SPE) was used for the extraction of target compounds from water samples. Then, a simplified proliferation test with human estrogen receptor-positive MCF-7 breast cancer cell and recombined yeast assay were applied to assess the estrogenic effect in effluent samples from different treatment stages in Tianjin reclaimed water treatment plant. Results The amount of extracts of reclaimed water inducing the maximum effect in cell proliferation assay was equal to that from 1.00 ml primary water. In recombined yeast assay, the amount of extracts of reclaimed water inducing maximum ?-galactosidase activity was equal to that from 20.00 ml primary water. Conclusion The effluent of reclaimed water treatment plant still shows estrogenic effect though slightly reduced.

Objective To study the mutagenic effect of reclaimed water in Tianjin. Methods Reverse phase C-18 solid-phase extraction (RP-C18SPE) was used for the extraction of target compounds from water samples. Ames test was used to detect mutation. Results PAHs were detected in both low-water and high-water period,including fluorene,phenanthrene,naphthalene,acenaphthylene and acenaphthene. In the high-water period, the total concentration of 16 kinds of PAHs was 1 777.9 ng/L and 1 380.1 ng/L in untreated reclaimed water and treated reclaimed water respectively, in the low-water period,it was 2 225.1 ng/L and 1 827.1 ng/L respectively. Ames test showed that both untreated reclaimed water and treated reclaimed water could induce mutation of TA98 and TA100 strains with a dose-response relationship. Conclusion The reclaimed water used in Tianjin still contains PAHs of a certain level, which have mutagenic effect.

Objective To understand the expression of heat shock protein(HSP70)mRNA induced by chlorpyrifos in the hepatic tissue of rats.Methods Wistar rats aged 6 weeks were divided into 4 groups,12 in each including 6 male and 6 female,the rats in the experimental groups were treated with chlorpyrifos by gavage once a day at the doses of 17 mg/kg?bw,8.5 mg/kg?bw and 4.25 mg/kg?bw respectively for 14 consecutive days,one group was the negative control.After the exposure,the hepatic tissue was sampled to examine the expression of HSP70 mRNA by polymerase chain reaction(PCR).Results The expression of HSP70 mRNA in the hepatic tissue in the groups of 17 mg/kg?bw,8.5 mg/kg.bw was significantly up-regulated with a dose-response relationship compared with the negative control group.Conclusion The expression of HSP70 mRNA is a sensitive parameter for early exposure assessment of chlorpyrifos.

[Objective]To repair segmental bone defect with the composite of deproteinised cancellous bone,bone morphogenetic protein(BMP) and fibrin.[Method] Bone defects were created in 36 New Zealand rabbits on the bilateral radii and treated with three kinds of implantations:A,composite of deproteinised cancellous bone,BMP and fibrin;B,of deproteinised cancellous bone;C,blank control.The defects were observed by entgenography,optical microscopy,and electron-microscopy at 2,4,8,12,16 weeks.[Result] The defects treated with A implantation regenerated much more new bone and bridged earlier than the defects treated with B implantation and got completely repaired 16 weeks after operation.The defects with B and C implantation couldn't get osseous tissue healing.[Conclusion]The composite of deproteinised cancellous bone,bone morphogenetic protein(BMP) and fibrin can be effectively used to repair segmental bone defect.

[Objective]To investigate the effect of an effervescent-sucrose on the properties of calcium phosphate cement. [Method]The sucrose particles were mixed with CPC powder at sucrose/(sucrose+CPC powder) mass percentage of 0%,10%,20%,30%,40%.The samples were characterized by compressive strength,X-ray diffraction,SEM techniques and degradation in vivo.[Result]The samples decreased on the mechanical properties and increased on the rate of macropore and total porosity,they were effected significantly among groups by added effervescent(P

Objective To assess the effects of three way catalytic converter on the health risk of benzene series.Methods After collecting the benzene series(benzene,toluene,xylene) in the air inlet and air outlet of the three way catalytic converser in 100% working loads,their health risk was assessed with the methods of health risk assessment.Results After catalysis,the hazard index of toluene and xylene decreased in all loads,the hazard index and carcinogenesis risk of benzene increased in 100% loads,the chronic long-term hazard index of benzene deceased in 100% loads.Conclusion The three way catalytic converter can change the health risk of benzene series emission by gasoline engine,the carcinogenesis risk of benzene series emission will be increased when the gasoline is treated with the three way catalytic converter.

Objective To analyze the association HLA DQ gene polymorphism to MG susceptibility.Methods HLA DQA1 and DQB1 were genetyped using PCR RFLP Results Comparing the frequency of HLA DQA1 alleles between MG patients with hyperplasia or MG males with disease onset less than 30 years and the healthy controls It was found that the frequency of DQA1*0301 was significantly increased Furthermore,in comparison with the frequency of HLA DQB1 alleles between MG patients (included subgroups)and the healthy controls,the frequency of DQB1*0303 was significantly increased,while the frequencies of DQB1*0601 and DQB1*0602 were significantly decreased And these differences were statistically significant. Conclusions HLA DQA1*0301 contributes to the genetic susceptibility of MG with hyperplasia and MG males with disease onset ≤30 years old DQB1*0303 was susceptible to MG DQB1*0601 and DQB1*0602 were protective genes