Objective:To explore the potential mechanism underlying IL-6 production through the TLR7 signaling pathway,which regulates Th17 cell differentiation in the context of Coxsackievirus B3(CVB3)-induced acute viral myocarditis(AVMC).Meth-ods:A total of 110 patients diagnosed with AVMC were admitted to Quanzhou First Hospital,Fujian between January 2020 and Janu-ary 2023,alongside 93 healthy volunteers.CD4+T cells were isolated from the subjects'blood,and the levels of CVB3 and the number of Th17 cells were assessed.Subsequently,CD4+T cells were infected with CVB3,and the levels of Th17 cells,IL-17,IL-21,and TNF-α were measured.After knockdown of TLR7 or treatment with TLR7 inhibitors,the differentiation of CVB3-infected CD4+T cells into Th17 cells was observed.Results:In comparison to healthy controls,AVMC patients exhibited elevated plasma levels of hsCRP,IL-17,IL-21,and TNF-α(P<0.05).The levels of CVB3 mRNA in CD4+T cells were also notably higher in AVMC patients compared to healthy controls(P<0.05).The mean viral titer in AVMC patients measured 230 PFU/ml,while no detectable virus was found in healthy volunteers(P<0.05).In CD4+T cells,the count of Th17 cells was significantly increased in AVMC patients compared to healthy volunteers(P<0.05).Moreover,the number of Th17 cells in peripheral blood CD4+T cells of AVMC patients showed a positive correlation with CVB3 virus titer(P<0.05).Following CVB3 infection,the number of Th17 cells increased compared with the control group(P<0.05),accompanied by elevated levels of IL-17,IL-21,and TNF-α in the supernatant(P<0.05).Knockdown of TLR7 and CVB3 infection in CD4+T cells significantly reduced the levels of Th17 cells(P<0.05),while the expression level of phosphorylated-activated TLR7 increased significantly after CVB3 infection of CD4+T cells compared to the control group(P<0.05).Treatment with the TLR7 inhibitor M5049 and CVB3 infection led to a significant decrease in Th17 cell levels(P<0.05).The secretion of IL-6 in CD4+T cells increased after CVB3 infection(P<0.05),and this increase was mitigated by TLR7 knockdown and CVB3 infection(P<0.05)as well as TLR7 inhibitor M5049 treatment and CVB3 infection(P<0.05).Conclusion:CVB3 activates TLR7 via phosphoryla-tion,prompting CD4+T cells to release IL-6 and undergo differentiation into Th17 cells.Consequently,TLR7 emerges as a promising therapeutic target for AVMC.

Objective:To explore the potential mechanism underlying IL-6 production through the TLR7 signaling pathway,which regulates Th17 cell differentiation in the context of Coxsackievirus B3(CVB3)-induced acute viral myocarditis(AVMC).Meth-ods:A total of 110 patients diagnosed with AVMC were admitted to Quanzhou First Hospital,Fujian between January 2020 and Janu-ary 2023,alongside 93 healthy volunteers.CD4+T cells were isolated from the subjects'blood,and the levels of CVB3 and the number of Th17 cells were assessed.Subsequently,CD4+T cells were infected with CVB3,and the levels of Th17 cells,IL-17,IL-21,and TNF-α were measured.After knockdown of TLR7 or treatment with TLR7 inhibitors,the differentiation of CVB3-infected CD4+T cells into Th17 cells was observed.Results:In comparison to healthy controls,AVMC patients exhibited elevated plasma levels of hsCRP,IL-17,IL-21,and TNF-α(P<0.05).The levels of CVB3 mRNA in CD4+T cells were also notably higher in AVMC patients compared to healthy controls(P<0.05).The mean viral titer in AVMC patients measured 230 PFU/ml,while no detectable virus was found in healthy volunteers(P<0.05).In CD4+T cells,the count of Th17 cells was significantly increased in AVMC patients compared to healthy volunteers(P<0.05).Moreover,the number of Th17 cells in peripheral blood CD4+T cells of AVMC patients showed a positive correlation with CVB3 virus titer(P<0.05).Following CVB3 infection,the number of Th17 cells increased compared with the control group(P<0.05),accompanied by elevated levels of IL-17,IL-21,and TNF-α in the supernatant(P<0.05).Knockdown of TLR7 and CVB3 infection in CD4+T cells significantly reduced the levels of Th17 cells(P<0.05),while the expression level of phosphorylated-activated TLR7 increased significantly after CVB3 infection of CD4+T cells compared to the control group(P<0.05).Treatment with the TLR7 inhibitor M5049 and CVB3 infection led to a significant decrease in Th17 cell levels(P<0.05).The secretion of IL-6 in CD4+T cells increased after CVB3 infection(P<0.05),and this increase was mitigated by TLR7 knockdown and CVB3 infection(P<0.05)as well as TLR7 inhibitor M5049 treatment and CVB3 infection(P<0.05).Conclusion:CVB3 activates TLR7 via phosphoryla-tion,prompting CD4+T cells to release IL-6 and undergo differentiation into Th17 cells.Consequently,TLR7 emerges as a promising therapeutic target for AVMC.

Objective: To evaluate the clinical application of single-arm external stent combined with free flap in the treatment of forearm fractures of Gustilo type Ⅲ. Methods: A retrospective study was conducted of the 16 patients who had been treated at Repair and Reconstruction Center, Traditional Chinese Medicine Hospital Affiliated to Southwest Medical University from September 2015 to January 2018 for open forearm fractures combined with soft tissue defects with single-arm external stent combined with free flap. They were 11 men and 5 women, aged from 18 to 64 years (average, 41.6 years). By the Gustilo classification, 9 cases were type ⅢB and 7 type ⅢC. The area of soft tissue defects at the upper arm and hand ranged from 7.5 cm×5.5 cm to 16.5 cm × 11.0 cm. Emergency debridement was performed at the primary stage. After repair of major blood vessels, nerves and tendons, the reduced fractures were fixated with a single-arm external stent. The soft tissue defects were repaired with free flaps at the secondary stage. Nine cases were repaired with a free anterolateral perforating branch flap and 7 with a free ilioinguinal flap. The single-arm external stent became the ultimate fixation mode in 5 cases but was changed into plate fixation after survival of the flaps in the other 11 cases. Complications were recorded postoperatively. At the last follow-up, the upper limb function was evaluated according to the tentative criteria for evaluation of the upper limb function proposed by the Hand Surgery Society of Chinese Medical Association. Results: Of all the free flaps, 14 survived smoothly but 2 anterolateral ones survived only after the venous crisis appearing at 24 h after operation was relieved by exploration. The 16 patients were followed up for 9 to 18 months (average, 13.5 months). The fractures united well with fine alignment of the fracture ends and recovered force line. According to the Anderson criteria for forearm fractures, 10 cases were excellent, 4 good and 2 fair after operation. According to the tentative criteria for evaluation of the upper limb function proposed by the Hand Surgery Society of Chinese Medical Association, 11 cases were excellent and 5 good. No nail infection or nonunion occurred. Conclusion In the treatment of forearm fractures of Gustilo type Ⅲ, single-arm external stent plus free flap can effectively restore the force line of upper extremity, promote bone healing, allow reasonable timing for wound repair, reduce postoperative complications like infection and osteomyelitis and facilitate functional recovery of the affected extremity.