BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene manipulation for the treatment of osteoarthritis may not produce satisfactory results.Previous studies have shown that nuclear factor κB could promote the inflammatory pathway in osteoarthritic chondrocytes,and bone morphogenetic protein 4(BMP4)could promote cartilage regeneration.OBJECTIVE:To test whether combined application of AAV-p65shRNA and AAV-BMP4 will yield the synergistic effect on chondrocytes regeneration and osteoarthritis treatment.METHODS:Viral particles containing AAV-p65-shRNA and AAV-BMP4 were prepared.Their efficacy in inhibiting inflammation in chondrocytes and promoting chondrogenesis was assessed in vitro and in vivo by transfecting AAV-p65-shRNA or AAV-BMP4 into cells.The experiments were divided into five groups:PBS group;osteoarthritis group;AAV-BMP4 group;AAV-p65shRNA group;and BMP4-p65shRNA 1:1 group.Samples were collected at 4,12,and 24 weeks postoperatively.Tissue staining,including safranin O and Alcian blue,was applied after collecting articular tissue.Then,the optimal ratio between the two types of transfected viral particles was further investigated to improve the chondrogenic potential of mixed cells in vivo.RESULTS AND CONCLUSION:The combined application of AAV-p65shRNA and AAV-BMP4 together showed a synergistic effect on cartilage regeneration and osteoarthritis treatment.Mixed cells transfected with AAV-p65shRNA and AAV-BMP4 at a 1:1 ratio produced the most extracellular matrix synthesis(P<0.05).In vivo results also revealed that the combination of the two viruses had the highest regenerative potential for osteoarthritic cartilage(P<0.05).In the present study,we also discovered that the combined therapy had the maximum effect when the two viruses were administered in equal proportions.Decreasing either p65shRNA or BMP4 transfected cells resulted in less collagen Ⅱ synthesis.This implies that inhibiting inflammation by p65shRNA and promoting regeneration by BMP4 are equally important for osteoarthritis treatment.These findings provide a new strategy for the treatment of early osteoarthritis by simultaneously inhibiting cartilage inflammation and promoting cartilage repair.

BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene manipulation for the treatment of osteoarthritis may not produce satisfactory results.Previous studies have shown that nuclear factor κB could promote the inflammatory pathway in osteoarthritic chondrocytes,and bone morphogenetic protein 4(BMP4)could promote cartilage regeneration.OBJECTIVE:To test whether combined application of AAV-p65shRNA and AAV-BMP4 will yield the synergistic effect on chondrocytes regeneration and osteoarthritis treatment.METHODS:Viral particles containing AAV-p65-shRNA and AAV-BMP4 were prepared.Their efficacy in inhibiting inflammation in chondrocytes and promoting chondrogenesis was assessed in vitro and in vivo by transfecting AAV-p65-shRNA or AAV-BMP4 into cells.The experiments were divided into five groups:PBS group;osteoarthritis group;AAV-BMP4 group;AAV-p65shRNA group;and BMP4-p65shRNA 1:1 group.Samples were collected at 4,12,and 24 weeks postoperatively.Tissue staining,including safranin O and Alcian blue,was applied after collecting articular tissue.Then,the optimal ratio between the two types of transfected viral particles was further investigated to improve the chondrogenic potential of mixed cells in vivo.RESULTS AND CONCLUSION:The combined application of AAV-p65shRNA and AAV-BMP4 together showed a synergistic effect on cartilage regeneration and osteoarthritis treatment.Mixed cells transfected with AAV-p65shRNA and AAV-BMP4 at a 1:1 ratio produced the most extracellular matrix synthesis(P<0.05).In vivo results also revealed that the combination of the two viruses had the highest regenerative potential for osteoarthritic cartilage(P<0.05).In the present study,we also discovered that the combined therapy had the maximum effect when the two viruses were administered in equal proportions.Decreasing either p65shRNA or BMP4 transfected cells resulted in less collagen Ⅱ synthesis.This implies that inhibiting inflammation by p65shRNA and promoting regeneration by BMP4 are equally important for osteoarthritis treatment.These findings provide a new strategy for the treatment of early osteoarthritis by simultaneously inhibiting cartilage inflammation and promoting cartilage repair.

Objective: To determine whether noncontrast computed tomography (NCCT) models based on multivariable, radiomics features, and machine learning (ML) algorithms could further improve the discrimination of early hematoma expansion (HE) in patients with spontaneous intracerebral hemorrhage (sICH). Materials and Methods: We retrospectively reviewed 261 patients with sICH who underwent initial NCCT within 6 hours of ictus and follow-up CT within 24 hours after initial NCCT, between April 2011 and March 2019. The clinical characteristics, imaging signs and radiomics features extracted from the initial NCCT images were used to construct models to discriminate early HE. A clinical-radiologic model was constructed using a multivariate logistic regression (LR) analysis. Radiomics models, a radiomics-radiologic model, and a combined model were constructed in the training cohort (n = 182) and independently verified in the validation cohort (n = 79). Receiver operating characteristic analysis and the area under the curve (AUC) were used to evaluate the discriminative power. Results: The AUC of the clinical-radiologic model for discriminating early HE was 0.766. The AUCs of the radiomics model for discriminating early HE built using the LR algorithm in the training and validation cohorts were 0.926 and 0.850, respectively.The AUCs of the radiomics-radiologic model in the training and validation cohorts were 0.946 and 0.867, respectively. The AUCs of the combined model in the training and validation cohorts were 0.960 and 0.867, respectively. Conclusion NCCT models based on multivariable, radiomics features and ML algorithm could improve the discrimination of early HE. The combined model was the best recommended model to identify sICH patients at risk of early HE.

BACKGROUND: Osteoarthritis is a common cause of pain and disability in the elderly. The underlying cause is the combination of inappropriate mechanical stress, inflammatory mediators and biochemical factors. Curcumin has been shown to have anti-oxidant, anti-inflammatory, anti-bacterial, anti-tumor, neuroprotective, and cardioprotective effects, radiation protection and therapeutic effects on osteoarthritis. Similarly, magnesium sulfate can relieve joint pain and inhibit joint destruction. OBJECTIVE: To investigate the mechanism by which the combined use of curcumin and magnesium sulfate exerts synergistic effect to promote inflammatory chondrocyte reverse differentiation.METHODS: Primary cultured inflammatory chondrocytes were subjected to monolayer culture in vivo. Cell proliferation assay (MTS) was used to detect the proliferation of inflammatory chondrocytes under in vitro monolayer culture conditions. The experimental cells were divided into four groups and underwent 3D induced reverse differentiation culture for 18 days: single culture of chondrocytes (chondrocyte group) , inflammatory chondrocyte cultured with curcumin (curcumin group) , inflammatory chondrocytes cultured with magnesium sulfate (magnesium sulfate group) , and inflammatory chondrocytes cultured with curcumin and magnesium sulfate (combination group). RESULTS AND CONCLUSION: MTS proliferation experiments showed that inflammatory chondrocytes at passage 3 had a higher rate of early proliferation and a lower degree of differentiation. Quantitative PCR results showed that the mRNA levels of type II collagen, proteoglycan and SOX9 were significantly higher in the combination group than in the curcumin group or magnesium sulfate group (P < 0.01). The size of the gross specimens and the positive area of chondrocyte reverse differentiation for alcian blue staining and safranin O staining in the combination group were significantly larger than those in the other three groups (P < 0.01). TUNEL staining results indicated that the positive area of apoptosis-specific staining in the combination group and magnesium sulfate group was significantly smaller than that in the other two groups (P < 0.01). Therefore, the combined use of curcumin and magnesium sulfate has the synergistic effect to promote the reverse differentiation of inflammatory chondrocytes.

BACKGROUND:Mesenchymal stem cells from human skeletal muscle exhibit multi-directional differentiation potential under the influence of osteogenic proteins such as bone morphogenetic protein 4 (BMP4). But the differentiation of a specific cell subpopulation is not yet clear.OBJECTIVE:To characterize the multi-directional differentiation potential of mesenchymal stem cells from human skeletal muscle based on the expression of different surface markers.METHODS:Four different subpopulations were isolated from the human skeletal muscle by fluorescence-activated cell sorting based on their expression of the myogenic-specific marker CD56 and the endothelial-specific markers CD34 and CD144, including CD56+, CD56+CD34+CD144+, CD34+CD144+, and unsorted groups. Osteogenic differentiation of the four groups of the cells was displayed by Von Kossa staining after the treatment with BMP4 alone or BMP4 plus transforming growth factor β3. Chondrogenic differentiation of these cells was displayed by Alcian blue staining. Bone metabolism was assessed by alkaline phosphatase staining.RESULTS AND CONCLUSION:No significant difference in the bone metabolism was found among four groups after the treatment with BMP4 (P > 0.05). Osteogenic and chondrogenic potentials of the four cell subpopulations were significantly different. Under the same osteogenic induction, the CD56+ cells exhibited strongest potential for osteogenic differentiation; and under the same chondrogenic induction, the CD56+CD34+CD144+ cells exhibited better potential for chondrogenic differentiation than the CD56+ cells. These findings indicate that the osteogenic and chondrogenic potentials are intimately associated with the type of mesenchymal stem cells from human skeletal muscle:the CD56+ cells are closely related to the osteogenic potential, while the CD56+CD34+CD144+ cells have stronger chondrogenic potential.