Objective To observe the proliferation and differentiation properties of rat skeletal muscle satellite cells that are dissected,cultured and purified in vitro and investigate their response to stimulation by insulin-like growth factor I(IGF-I).Methods The cells were isolated from Wistar rats by two-step enzyme digestion and purified by the Percoll density centrifugation to observe their prolif- eration and differentiation properties and draw growth curve and fusion rate curve.Then,the response of the satellite cells to stimulation by IGF-I at various concentrations was determined by using MTT meth- od.Results Plenty and purified satellite cells were obtained via these methods.Conclusion IGF- I at appropriate concentration(100 ng/ml)can promote the proliferation and differentiation of rat skele- tal muscle satellite cells.

Objective To observe the effect which the skeletal muscle satellite cells were transplanted on denervated skeletal muscle atrophy so as to provide the experimental data for treating denervated muscle atrophy in vivo. Methods Thirty-two Sprague-Dawley rats weighting 200-250 g were randomly divided into control group and experimental group. Each group included 16 rats, the animal model of denervated gastrocnemius muscles were formed by cutting the right sciatic nerve of rats caused nerve despair about 1 cm. Muscle satellite cells were obtained from the dorsal and lower exterenity muscle of SD rats. Before transplantation, muscle satellite cells being labeled with DAPI (4′-6-Diamidino-2-Phenylin Dole) in vitro. Muscle satellite cells and NS were implanted into denervated skeletal muscle from the two groups. Bilateral gastrocnemius muscles of each rat from the two groups were taken and weighed at second and eighth post-operative weeks respectively. The above muscles underwent anti-actin immunohistochemical and HE staining and muscle cross-sectional area of fiber and the actin content of the rats were measured by the image analysis, the data of which was handled with SPSS software. Results The satellite cells and myofiber with fluorescence were observed in transplantation site. The group of skeletal muscle satellite cells transplanted when two weeks and eight weeks denervated gastrocnemius muscle wet weight remnant rate and muscle cross-sectional areas of fiber remnant rate and muscle actin content were better than in the control group respectively(P

Objective To establish the technique of biphasic seeding of articular chondrocyte s in vitro for cartilage engineering in u sing a self designed biological gel a nd the three-dimensional scaffold a nd observe the efficiency of cartilage regeneration in vitro-tissue engin eered articular cartilage from cell scaffold complex.Methods The articular chondrocytes were iso lated enzymatically from the epiphyseal cartilage of young rabbits,and were then plated i nto the tissue culture flasks and were cultivated.The first passage ar-ticular chondrocytes were collecte d and mixed fully with the self-made l iquid biological gel-matrix at appr oxi-mately 2.5?10 7 cells /ml to form cell-gel fluid.The cell-gel fluid was dropped into the p orous CPPf /PLLA(calcium polyphosphate fiber /poly -L -lactic acid)scaffold,and a cell-gel-scaffold c omplex was formed after being solidified.The complexes were cultivated for 4weeks.The changes of complexes in morphology and synthesis of collagen typeⅡandⅠand aggregates were investigated under the gross and the phase and light microscope.The GAG sulfate content in complexes was quantitatively mea sured by the modified dimethyl-methylene blue method.Results1)After feeded,the porous CPPf /PLLA s caffolds were completely filled with the liquid chondrocyte-gel and the chondrocyte-gel-scaffold comp lexes were well formed by solidification.During the cultivation,the complex es could keep its original shape and m aintain the stable homogeneous three-dimensional distribution of chondrocytes in themselves without cell falling.In the same time,the com-plexes were gradually increasing th e consistency with the elasticity an d lubrication surface.2)The chondro-genesis began in the periphery area a nd extended to the central area of the complexes with the passage of cultivation period.After the 2nd we ek,the complexes were gradually reorganized into the mature engineered cartilage with typical cartilaginous histological structure,with ric h typeⅡcollagen and the strong typical het-erochromia to toluidine blue,but wi th gradually fading negative immunological stain of collagen typeⅠ.Meantime,the scaffold was graduall y de-graded in the complexes.The average content of GAG sulfate in the enginee red cartilages at 4th week was(15.70?2.00)mg /g(wet weight ),and was over 30%of the natural articular cartila ge.Conclusion The technique of chondrocytes biphasic seeding for three-dimensional scaffold has advantages of simple manipulation,fix ing cell stably in the scaffold,main-taining the original shape of the com plexes and the stable homogeneous th ree-dimensional distribution of chondrocytes in the scaffold,and ad vancing the regeneration and matura tion of tissue-engineered articula r cartilage.[

Objective To establish the methods of efficiently isolating chondrocytes from epiphyseal cartilage and observe the basic biological characteristics of the cultured ones. Methods The improved isolation method through three-step enzymatic digestion using 1 g/L trypsase in 1 g/L ethylenediaminetetraacetic acid, 1 g/L hyaluronidase and 2 g/L type Ⅰ collagenase was established to isolate the primary passage chondrocytes from epiphyseal cartilage of young rabbits and its efficiency evaluated. The cellular biological characteristics of the chondrocytes were observed under the inverted and light microscopes. Results (1) All chondrocytes were isolated from the matrix after it was completely digested by three above-mentioned enzymes. The harvested chondrocytes significantly and positively correlated with the wet weight of cartilage. The number of chondrocytes from 1 g of wet cartilage was 32.3?106 with a viability of 97.6% on average. (2) The chondrocytes of the primary and the first passages showed triangle or multi-angle shapes (oval during growth and fusion) with the positive immunohistochemical stain of collagen type Ⅱ and the strong heterochromia to toluidine blue. The chondrocytes after the third passage became spindle-shaped with the negative stain of collagen type Ⅱ and the weak heterochromia to toluidine blue. Conclusions (1) The chondrocyte-isolating method through three-step enzymatic digestion has advantages of high efficiency in harvesting primary chondrocytes, high cellular viability and simple manipulation. (2) The chondrocytes differentiate and lose their special phenotypes gradually with passage.

Objective To investigate the regulative effect of interferon gamma (INF?) on the expression of platelet-derived endothelial cell growth factor / thymidine phosphorylase (PD-ECGF/TP) and its relation with the anti-cancer effect of 5′-deoxy-5-fluorouridine (5'DFUR) and 5-fluorouracil (5FU) in T24 bladder cancer cells. Methods PD-ECGF/TP mRNA and protein expressions were determined by RT-PCR and Western blot,respectively.Cytotoxicity of 5′DFUR,5FU or mitomycin C (MMC) against T24 cells was evaluated by MTS assay. Results The expressions of PD-ECGF/TP mRNA and protein were concomitantly elevated in T24 cells after INF? treatment.And INF? decreased IC 50 s of 5′DFUR [from (16.0? 3.6 )mmol/L to (6.2?0.9)mmol/L,( P

BACKGROUND:Human umbilical cord mesenchymal stem cells are similar to bone marrow mesenchymal stem cells, which can directional y differentiate into neuron-like cells, secrete various cytokines, and provide the base for nerve regeneration. ＜br> OBJECTIVE:To study the role of chitosan composite nerve conduit carrying umbilical cord mesenchymal stem cells in nerve end-to-side anastomosis. ＜br> METHODS:Thirty while rabbits were randomized into three groups. The central branch of the right posterior peroneal nerve were cut and proximal y ligated, and then sutured evaginably to the muscle. In the control group, the distal end of the common peroneal nerve were anastomosed into the tibial nerve at 30°-45°;in the stenting group, the chitosan conduit was bridged at the same interval and angle into the end-to-side anastomosis site between the tibial nerve and peroneal nerve;in the cel-stenting group, the chitosan conduit carrying human umbilical cord mesenchymal stem cells was bridged at the same interval and angle into the end-to-side anastomosis site between the tibial nerve and peroneal nerve. After 12 weeks, gross observation, neurophysiological examination and anti-S-100 immunohistochemistry detection were performed. ＜br> RESULTS AND CONCLUSION:After 12 weeks of operation, in the cel-stenting group, the conduit degraded completely, the nerve diameter was similar to that of the normal peroneal nerve, and the motor nerve conduction velocity was higher than that in the control and stenting groups (P＜0.01). Anti-S-100 immunohistochemistry results showed that a great amount of brownish red Schwann cells arranged around the regenerated nerve fibers in the cel-stenting group, while there was few and sparse brownish red substance, and the Schwann cells grew worse in the stenting and control groups. These findings suggest that umbilical cord mesenchymal stem cells have an obvious role in promoting nerve regeneration, induce bud growth, accelerate the growth rate of regenerated fibers, and improve growth and maturity of Schwann cells.

Administration, Oral ; Chronic Disease ; Glucocorticoids ; administration & dosage ; therapeutic use ; Humans ; Sinusitis ; drug therapy

BACKGROUND:It is a mature technology to culture MC3T3-E1 cels in the self-assembling peptide hydrogel, RADA16-NBD. Moreover, it is confirmed that a variety of metal ions, such as Fe, Cu, Zn, Mn, are involved in normal bone metabolism.
OBJECTIVE:To observe the effect of Cu2+and Fe3+ on the proliferation and differentiation of MC3T3-E1 cels cultured in the self-assembling peptide hydrogel, RADA16-NBD.
METHODS: Osteoblasts cultured with RADA16-NBD were divided into three groups and respectively cultured in culture medium containing Cu2+, Fe3+ or serum-free medium (control group), respectively. After 24, 48 and 72 hours, cel proliferation was detected by cel counting kit-8. After 1, 3, 5 days, alkaline phosphatase activity was detected. At 21 days, formation of calcified nodules was observed. Cel migration ability of cels was observed at 24 hours of Transwil chamber culture.
RESULTS AND CONCLUSION:Compared with the control group, the proliferative ability of cels cultured in the Cu2+, Fe3+ groups was significantly higher (P < 0.05,P < 0.01). At 72 hours of culture, there was no difference in the cel proliferation among the three groups. At 1, 3, 5 days of culture, the alkaline phosphatase activity in the Cu2+, Fe3+ groups was significantly higher than that in the control group (P < 0.05); while at 3 and 5 days of culture, the alkaline phosphatase activity in the Cu2+ group was significantly higher than that in the Fe3+ group (P < 0.05). In addition, the number of migrated cels was higher in the Cu2+ group than the Fe3+ group (P < 0.05). These findings indicate that both Cu2+ and Fe3+, especialy the former one, can promote MC3T3-E1 cel proliferation, differentiation and migration.

Objective: To isolate and characterize the highly tumorigenic cancer stem cells with stem cell features from the established human lung adenocarcinoma cell lines. Methods: The cell subtypes were separated by magnetic activated cell sorting (MACS) technique. The stem cell-related markers on the isolated cells were detected by using flow cytometry and RT-PCR. The tumorigenic potent of the isolated cells was evaluated via the transplantation into NOD-SCID mice. Results: A novel cell subtype was identified in A 549 and SPC-A1 lung adenocarcinoma cell lines. These cells were characterized as a phenotype of CD 24+ IGF-1R+, possessed the property of high invasiveness and high tumorigenesis. Tumor could be induced in NOD-SCID mice by transplantation of CD 24+IGF-1R+ cells at 100 cells per mouse. The tumorigenicity of CD 24+IGF-1R+ cells had 1000-fold increase compared with CD 24-IGF-1R- cells. In addition, the CD 24+IGF-1R+ cells expressed embryonic stem cell markers (OCT 4 and Bmi-1) and lung stem cell markers (CCSP, SP-C, TTF-1, and Gremlin), suggesting that they had the features identical to the bronchioalveolar stem cells (BASC) in the lung of mice. These cells also exhibited autonomous growth features and could be cultured in serum-free conditions for a long time. Conclusion: The CD 24+IGF-1R+ cells in human lung adeocarcinoma belongs to the BASC-like cancer stem cells.

Objective To observe the effect of arthroscopic meniscectomy to tr eat discoid lateral meniscus tear. Methods From July 1999 to June 2003, arthrosc opic meniscectomy was conducted for 49 menisci of 45 patients with discoid later al meniscus tear. 41 patients had unilateral injury, and 4 bilateral. 32 knees w ere complete injury and 17 incomplete. The discoid lateral meniscus tear account ed for nearly one third of the patients with meniscus tear who received arthrosc opic meniscectomy at the same time. Arthroscopic partial meniscectomy was done f or 44 knees, total meniscectomy for 5 knees and meniscus suture for 3 knees. Aft er operation the rehabilitation training programs, including straight-leg-rais ing exercise and range-of-motion exercise, were carried out. Results The opera tions for the 45 cases were successful and there was no complication. 40 patient s were followed up. Before operation, the mean Lysholm -Ⅱscore was 55 points ( 40 to 71 points). After a mean follow-up period of 39 months, the mean Lysholm -Ⅱscore was 88 points (60 to 100 points). The excellent and good results were obtained in 85.3%of the patients. Conclusions Arthroscopic meniscectomy should be a preferred method for discoid lateral menisci tear, due to its minimal invas ion, possibility of early mobilization, a lower complication rate, and preservat ion of more meniscus structure and function. If the operation is combined with s tandard rehabilitation training, the effects can be enhanced.