Congresses as Topic ; Otolaryngology

Objective To search for a good method for generation of hematopoietic stem cells (HSC) by embryonic stem cells (ESC),and to investigate the potential of HSC derived from ESC to reconstruct hematopoiesis in vivo.Methods Using a three-step method to induce a mice ESC line, E14.1-into HSC.And identifying HSC by flow cytometry analysis cell markers with CD34 +/Sca-1+, then HSC (1×109L-1)from ESC differentiation were injected into severe combined immunodefieency (SCID) mice for observing teratoma formation.To validate function of HSC by colonngenic cells assay and to reconstitute the hematopoiesis in lethally irradiated mice.Results Combining to use more hematopoietic stimulating factor to availably promote the El4.1 cell into embryoid body (EBs) with abundant hematopoietic progenitors.EBs were induced after 14 day to fast differentiate for HSC with peak percentages of CD34+/Sca-1+ cells reached to (13.72±2.07)%.To harvested ceils from EBs by day 14 for second -step HSC differentiation, percent of CD34+/Sca-1+ cells rise to(24.62±2.50) % after day 16 induction.Cloning forming units (CFU) analysis showed that more Erythro -myeloid cloning generation was observed at this period.Cells obtained in the second step are subsequently plated on monolayer of mice bone marrow stromal cells, in the presence of TPO, FLt3 ligand and superoatant of mice fetal liver stromal cells, cultured for additional 15 days, followed fast expansion of CD34+/Sca-1+ to maximally (58.64±4.20 ) % with more CFU-E, CFU-GM and CFU-GEMM population.Wright-Giemsa stain showed that its had the character of hematopoietic progenitors.Cells from the third-step were injected into SCID mice, but no teratomas were recovered in 2 mices after 6 weeks.Positive selection of CD34+/Sca-1+ cells by magnetic sorting from the third - step differentiation were transplanted into 7 lethally irradiated female mice while predominant hematopoietic reconstitution were observed in 10 days after transplantation, with 71.4% successful engraftment rate.And 3 recipients showed that the cell population of the peripheral blood leukocytes,red cells, hemoglobin approached normal index at 40 days after transplant, hut followed relative'slow renew in platelet count.Survival rate of transplant group is 43.0%, compared to 100% mortality in control mice.Karyotyping assays confirmed female mice with XY.Conclusions The results showed that the three-step differentiation and the culture conditions described here good support differentiation of ESC into HSC.HSC derived from ESC were safe without teratomas formation in body, and its can reconstruct hematopoiesis.

Objective To establish a normal lumbar spine 3-dimensional(3D) finite element model(FEM) and discuss the biomechanics of the lumbar motions. Methods A geometrical model was constructed on the basis of a healthy adult male's lumbar CT image.The lumbar spine FEM was established by finite element analysis software.After setting the boundary and loading the burden,the lumbar spine's range of motion and stress distribution in different institutions such as anterior flexion,posterior extension,left or right bending and axial rotating were recorded. Results The lumbar spine FEM included 114 953 tetrahedron units.The results of the FEM matched the results of the in vitro experiment of biomechanics. Conclusion The lumbar spine FEM can imitate the motions of the lumbar spine.

Animals ; Cholesterol ; blood ; Hyperlipidemias ; blood ; drug therapy ; Leptin ; pharmacology ; therapeutic use ; Male ; Mice ; Mice, Inbred Strains

Humans ; Infant ; Male ; Mycobacterium tuberculosis ; Otitis Media ; microbiology ; Tuberculosis

Child ; Choristoma ; Humans ; Male ; Neck ; pathology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Thymus Gland ; pathology ; Thymus Neoplasms

Under the shaking-flask culture, fermentation medium of honggumycin produced by Streptomyces 702 were studied.The experiment was used response surface methodology to optimize the shaking-flask fermentation medium.Firstly, we applied full factorial design to screen important factors soybean meal and industrial peptone which affected hongmycin produced by Streptomyces 702.Furthermore, we designed experiment to obtain the steepest ascent path and optimal level by the central composite design.The optimum medium consisted of (g/L): maize starch 20, maize meal 20, glucose 20, soybean meal 23, industrial peptone 9, KNO_ 3 2.5, (NH_ 4 )_ 2 SO_ 4 2.5 KH_ 2 PO_ 4 0.3, NaCl 3, CaCO_ 3 6, bean oil 5mL/L.Under the optimal medium, the yield of honggumycin was up to 1500 g/mL, which was increased by 308% than the original medium.

Objective To explore whether human umbilical venous endothelial cells could be used as feeder layer to support the growth of embryonic stem cells (ESC) and keep ESC undifferentiated.Methods The venous vessels of umbilical cord obtained from healthy puerperal were perfused with collagenase.The isolated endothelial cells went through primary culture and passages for expansion.Factor Ⅷ antigens determination was implemented.Endothelial cells with good growth and 3 or above passages were treated with mitomycin-C(10 mg/L) and prepared as feeder layer,on which E14.1 ESC was transplanted for subculturing to observe the morphological characterization and determine ESC alkaline psphatase (AKP) activity and the expression of stem cell marker Oct-4.Severe combined immune deficiency(SCID) mouse in vivo terotoma formation experiment was performed to identify its pluripotent properties.Results Human umbilical vein-derived endothelial cells grew well in culturing in vitro and regenerate in large numbers.The endothelial cells maintained normal cellular morphological and biological characterization after 10 passages.The cells stopped proliferating after being treated with mitomycin-C,but its activity and morphological properties were well-maintained with 24 hours,which was a fundamental property of serving as feeder layer.E14.1 ESC remained undifferentiated in human umbilical venous endothelial cells after 3-8 passages,the cells grew in colony and showed high expression of AKP and stem cell Oct-4.In vivo pluripotency experiment showed that 6 weeks after being transplanted to SCID mice E14.1 ESC of 6 and 10 passages in endothelial cells both could form teratoma containing 3 layers of tissue cells.Conclusions Human umbilical venous endothelial cell serve as a convenient feeder layer cell with rich sources.It can effectively support ESC growth and heterogenous and prevent the heterogeneous protein pollution and pathogenic microorganisms caused by animal cell feeder layers,thus solve the problem of biological safety of ESC clinical application.

Human herpes simplex virus 1 (HSV-1) causes facial,ocular,and encephalitic disease and is associated with latent infection and cancer.Here,we developed a means of studying the pathogenesis of HSV-1 infection at the protein level by using the SELDI Protein Chip to detect changes of protein expression in Vero cells cultured in vitro.After infection with HSV-1 and culture for 12,24 or 48 h,cells were harvested and lysed.IMAC3 arrays were applied to SELDI-TOF-MS to detect proteomic differences before and after infection.The chip detected a series of differentially expressed protein peaks.Interestingly,both peaks at 16 912 Da and 17 581 Da corresponded precisely with the molecular mass of ISG 15,which may participate in antiviral activity during the process of infection.Thus,the results we obtained can serve as a basis to study the pathogenesis of HSV-1 and the interaction between the virus and its host.In addition,they can help in the discovery of new therapeutic targets for treatment of HSV-1 infection.

Humans ; Infant ; Male ; Pulmonary Alveolar Proteinosis