Objective To explore the mechanism of the role of mitomycin C(MMC)in regulating miR-200b expression and inducing fibroblasts apoptosis. Methods Fibroblasts cultured in vitro were treated with different concentrations of MMC for 5 min and continue culture for 24 h. The expression of miR-200b were analyzed by Real-time PCR. Cell apoptosis were observed using TUNEL staining. The expression of cleaved-PARP,Bax and Bcl-2 were detected by Western blot. The methylation level of miR-200b promoter were measured by BSP. Results After treated with MMC,The expression of miR-200b significantly downregulated.TUNEL Staining analysis demonstrated MMC could significantly induce human fibroblasts apoptosis. Western blot results showed cleaved-PARP,Bax increased and Bcl-2 decreased.The methylation ratio of miR-200b promotor increased and has a significant dose dependent. Conclusion MMC induced human fibroblasts apoptosis by promoting miR-200b promoter methylation.

BACKGROUND:L-type calcium channels, as a kind of voltage-dependent calcium channel, is the main way of extracellular calcium ions into the cell, and play an important role in maintaining cellmorphology and physiological activities, characterized by a large single-channel conductance, slow channel attenuation, and longer duration of channel opening. Previous studies showed that basic fibroblast growth factor can promote the proliferation of chondrocytes cultured in vitro.
OBJECTIVE:To explore the effect of the L-type calcium channels on regulating chondrocyte proliferation and differentiation in response to basic fibroblast growth factor with patch-clamp.
METHODS:The chondrocytes were harvested from the joints of 3-day-old New Zealand rabbits. The second passage of chondrocytes was divided into experimental group and control group. Chondrocytes were incubated in media containing 10μg/L basic fibroblast growth factor and media alone separately. The opening of L-type calcium channels under the action of basic fibroblast growth factor was detected by patch-clamp. The intracellular calcium concentration was detected with laser confocal microscopy in the chondrocytes after 2 weeks of culture with basic fibroblast growth factor. Chondrocyte proliferation was analyzed by cellTiter kit after 8 days of culture. Type Ⅱ col agen was assessed quantitatively by immunohistochemistrical staining after 10 days of culture.
RESULTS AND CONCLUSION:Basic fibroblast growth factor has an inhibitory effect on the opening of the L-type calcium channels, resulting in a decrease in intracellular free calcium concentration (P<0.01). cellnumber was higher after culture with basic fibroblast growth factor than that cultured under conventional condition (P<0.01), and staining area of type II col agen significantly increased (P<0.05). Results verified that basic fibroblast growth factor can maintain intracellular Ca2+concentration at a low level by inhibiting the opening of L-type calcium channels, which can promote the proliferation and differentiation of chondrocytes.

BACKGROUND:Differences of knee anthropometry between individuals are significant, while preoperative templating is not accurate in predicting the prosthesis size.
OBJECTIVE:To improve the accuracy of pre-operative plan in predicting the prosthesis size in total knee arthroplasty using digital technologies.
METHODBetween January 2013 and May 2004, 50 patients (20 men and 30 women;aged 54-82 years;mean age, 67.8 years) received primary total knee arthroplasty for osteoarthritis and were retrospectively analyzed. According to the treatment, the patients were divided into two groups. The digital group, a series of 21 patients, underwent 64-row MDCT before total knee replacement. CT images were imported into Mimics, and three-dimensional models of femur and tibia were reconstructed. Then, computer-aided design files of different sizes of prostheses provided by the manufacturers were imported into Mimics, too. Surgical simulation of osteotomy and prostheses implantation were performed in Mimics, component size was determined by the contour of distal femur and proximal tibia. The control group, a series of 29 patients, underwent primary total knee arthroplasty using conventional approaches. The agreement between preoperative plan and the actual prosthesis size was assessed during the surgery. Postoperative X-ray of low limb was taken to evaluate the accuracy of sizing and the efficacy of digital technologies was assessed.
RESULTS AND CONCLUSION:The intraoperative and postoperative evaluation showed inaccurate sizing of femoral and tibial components in 1 case in digital group and in 11 cases in conventional group. The accuracy of prediction was 95%in digital group and 62%in conventional group, with significant differences between the two groups (P<0.05). Four overhanging and two notching cases were observed in conventional group, but none in digital group. The digital technologies provide an effective means for accurate prediction of prosthesis size and personalized surgical simulation.

The clinical characteristics and radiological data of 6 cases of sacral agenesis in one single family were analyzed and a literature review was performed.On magnetic resonance imaging (MRI),all of them presented with a partial absence of sacral vertebra,including associations with lumbar abnormalities (n =2) and sacral agenesis (n =2).One case presented with fourth/fifth lumbar vertebra bone fusion and fifth lumbar/first sacral vertebra bone fusion.On radiology,4 cases had concurrent scoliosis.None of them had tethered cord,diastematomyelia or meningocele.The understanding of sacral agenesis may be improved after reviewing and summarizing clinical features and radiological findings.

BACKGROUND:Experimental studies have showed that puerarin has an obvious protective effect on osteoporosis in ovariectomized and orchiectomized mice. But the influence of puerarin in the molecular level in the process of osteoblast differentiation is seldom reported.
OBJECTIVE:To observe the effect of puerarin on the mRNA expression of alkaline phosphatase, bone sialoprotein, osteopontin and osteocalcin in osteoblasts.
METHODS:The MC3T3-E1 cells from mice cultured in vitro were randomly divided into control group, puerarin group (10-6 mol/L puerarin) and estradiol group (10-7 mol/L estradiol) to observe the effects of puerarin on the differentiation of osteoblasts. mRNA expression of alkaline phosphatase, bone sialoprotein, osteopontin and osteocalcin in MC3T3-E1 cells was determined using RT-PCR method.
RESULTS AND CONCLUSION:Puerarin and estradiol both could prolong the expression of alkaline phosphatase that reached the peak at 12 days. Puerarin and estradiol strengthened the mRNA expression of bone sialoprotein at 10 and 12 days, reduced expression of osteopontin at 5 and 12 days, and increased expression of osteocalcin at 10 and 12 days. These results reveal that puerarin can induce the differentiation of cultured osteoblasts by influencing osteoblast differentiation-related protein mRNA expressions, which may be one of the important molecular mechanisms of puerarin for prevention of osteoporosis.

BACKGROUND:The pathogenesis of knee intraarticular adhesion is yet unknown. Excessive proliferation of fibroblasts is considered to cause knee intraarticular adhesion. OBJECTIVE:To study the preventive effects of methotrexate on knee intraarticular adhesion through fibroblast apoptosis induced by endoplasmic reticulum stress. METHODS:The viability of the cultured fibroblasts treated with methotrexate(10-5-10-9mol/L)or PBSwas determined after 24 hours. Fibroblast apoptosis was detected by Hoechst33342 staining. Endoplasmic reticulum stress-and apoptosis-related proteins, including cleaved-PARP, CHOP, Bax and Bcl-2, were determined by western blotassay. Eighteen healthy male New Zealand white rabbits were used to establish the knee intraarticular adhesion models, and equaly randomized into three groups, and received topical application of 2 or 1 g/L methotrexate, or normal saline (control). The preventive effects of methotrexate on knee intraarticular adhesion and CHOP expression in scar tissue were observed. RESULTS AND CONCLUSION:Methotrexate inhibited the proliferation and viability of fibroblasts in a dose-dependent manner. The number of apoptotic fibroblasts was significantly increased compared with control group. Protein expression of cleaved-PARP, CHOP, and bax was increased, while protein expression of bcl-2 was decreased with time. The animal experiment showed that preventive effects of 2 g/L methotrexate on knee intraarticular adhesion were superior to 1 g/L methotrexate treatment. CHOP expression in the scar tissue in the methotrexate groups was higher than the control group and that was higher in high-dose methotrexate group. Our results suggest that methotrexate prevents knee intraarticular adhesionviaendoplasmic reticulum stress-induced fibroblast apoptosis.

No abstract available.
Amniotic Fluid* ; Animals ; Female ; Fibrosis* ; Humans ; Hyaluronic Acid* ; Laminectomy* ; Mitomycin* ; Rats*

No abstract available.
Amniotic Fluid* ; Animals ; Female ; Fibrosis* ; Humans ; Hyaluronic Acid* ; Laminectomy* ; Mitomycin* ; Rats*

BACKGROUND: Intra-articular injection is a classic strategy for the treatment of early osteoarthritis (OA). However, the local delivery of traditional therapeutic agents has limited benefits for alleviating OA. Exosomes, an important type of extracellular nanovesicle, show great potential for suppressing cartilage destruction in OA to replace drugs and stem cellbased administration. METHODS: In this study, we developed a thermosensitive, injectable hydrogel by in situ crosslinking of Pluronic F-127 and hyaluronic acid, which can be used as a slow-release carrier to durably retain primary chondrocyte-derived exosomes at damaged cartilage sites to effectively magnify their reparative effect. RESULTS: It was found that the hydrogel can sustainedly release exosomes, positively regulate chondrocytes on the proliferation, migration and differentiation, as well as efficiently induce polarization of M1 to M2 macrophages. Intraarticular injection of this exosomes-incorporated hydrogel significantly prevented cartilage destruction by promoting cartilage matrix formation. This strategy also displayed a regenerative immune phenotype characterized by a higher infiltration of CD163+ regenerative M2 macrophages over CD86+ M1 macrophages in synovial and chondral tissue, with a concomitant reduction in pro-inflammatory cytokines (TNF-a, IL-1b, and IL-6) and increase in anti-inflammatory cytokine (IL-10) in synovial fluid. CONCLUSION Our results demonstrated that local sustained-release primary chondrocyte-derived exosomes may relieve OA by promoting the phenotypic transformation of macrophages from M1 to M2, which suggesting a great potential for the application in OA.

Objective To investigate the effect of amentoflavone(AMF)on inhibiting wear debris-in-duced osteolysis in vivo and RANKL-induced osteoclastogenesis in vitro. Methods Twenty-four male C57BL/J6 mice were randomly divided into four groups:the control group,titanium group,the low and high concentration group.Micro-CT and histological analysis were performed.CCK-8 assay was used to determin the effect of AMF on the proliferation of BMMs.TRAP staining and bone resorption assays were used to investigate the effect of AMF on osteoclastogenesis and function. The effect of AMF on prevention MAPK signaling was detected by Western blot assay. Results AMF could prevent osteolysis in vivo and suppress osteoclastogenesis,bone resorption without cytotoxicity in vitro.AMF suppressed MAPK signaling pathways.Conclusion AMF could inhibit osteoclastogenesis and titanium debris-induced osteolysis through suppressing MAPK signaling.