Objective To construct an injectable hydrogel(IH)entrapment system of bone marrow mesenchymal stem cells(BM-MSCs)and to explore its effect of promoting articular cartilage repair and underlying mechanism.Methods The primary BM-MSCs of mice were cultured by whole bone marrow adherent method.The differentiation potential was identified by alizarin red(ARS),oil red O(ORO)and Alcian blue(AB)staining,and the expres-sion of CD44,CD90,CD105,CD34 and CD45 on the surface was detected by flow cytometry.BM-MSCs loaded with IH(BM-MSC-IH)was prepared,and the rheological properties of BM-MSC-IH were tested by rheological test.The model of full-thickness injury of knee cartilage in mice was established,and the mice were randomly divided into normal saline group,BM-MSC group and BM-MSC-IH group with 8 in each.The mice were injected with BM-MSC-IH 0.2 mL,cell suspension 0.2 mL and 0.9％NaCl solidion,independently.After 6 and 12 weeks of in-jection,the repair of knee cartilage in mice was observed by safranin-fast green staining,and the expression of typeⅡ collagen in knee joint was examined by immunohistochemical staining microscopy.Results The primary cultured cells showed positive expression of CD44,CD90 and CD105,but negative expression of CD34 and CD45,and had the potential of osteogenic,adipogenic and chondrogenic differentiation.The constructed BM-MSC-IH sys-tem was solid colloid,and the rheological properties were consistent with the basic characteristics of hydrogel.BM-MSC-IH effectively promoted the regeneration of mouse knee cartilage and increase the local expression of typeⅡ collagen.Conclusions Bone marrow-mesenchymal stem cells embedded with injectable hydrogel effectively pro-mote the repair of injured cartilage and the underlying mechanism is potentially promoting the differentiation of chondrocytes and the expression of type Ⅱ collagen.Its effect is better than application of BM-MSCs alone.

Objective To explore the application value of popaverine combined with stage rehabilitation for patients after free flap grafting for hand trauma.Methods Data of postoperative patients who underwent hand trauma from January 2021 to January 2022 in The 903rd Hospital of the Joint Logistics Support Force of the People's Liberation Army of Chinawere retrospectively collected,and they were divided into the combined rehabilitation group(poppadine combined with stage rehabilitation care)and the stage rehabilitation group(only stage rehabilitation care was applied)according to the treatment methods.Visual analog scale(VAS)scores,rehabilitation exercise adherence scores,postoperative rates of excellent cutaneous sensory function of the hand,total active mobility(TAM)of the fingers,Jamar grip strength,upper extremity functional assessment(DASH)scale scores,and the incidence of vascular crises were compared between the two groups.Results A total of 120 cases were included in the study,with 57 cases in the combined rehabilitation group and 63 cases in the stage rehabilitation group.There was no statistically significant difference in VAS scores,Jamar grip strength and DASH scores between the two groups before surgery(P＞0.05);at 14 days and 3 months of intervention,VAS scores of the two groups decreased compared with the pre-intervention period(P＜0.05),and VAS scores of the patients in the combined rehabilitation group were significantly lower than those in the stage rehabilitation group(P＜0.05).After 3 months of intervention,the rehabilitation exercise adherence score,the rate of excellent hand skin sensory function,and finger TAM of the patients in the combined rehabilitation group were higher than those in the stage rehabilitation group(P＜0.05);Jamar grip strength were elevated in both groups compared with the pre-intervention period,but the combined rehabilitation group were higher than those in the stage rehabilitation group(P＜0.05);DSAH scores were lower in both groups compared to pre-intervention,and were lower in the combined rehabilitation group than in the stage rehabilitation group;and during the 3 months of intervention,the incidence of vascular crisis was significantly lower in patients in the combined rehabilitation group than in the stage rehabilitation group(P＜0.05).Conclusion Opium poppy alkaloids combined with stage rehabilitation can effectively reduce patients'postoperative pain,enhance patients'adherence to rehabilitation exercises,effectively improve postoperative hand function and upper limb motor function,and reduce the incidence of vascular crisis.