Objective To investigate the effects of BCG ( Bacillus Calmette-Guerin) infection on NKG2D (natural killer group 2, member D) ligands (MICA, MICB, ULBP1 and ULBP2) expressed on macrophages and to further analyze the effects of baicalin on these NKG2D ligands and the cytotoxic activity of NK cells. Methods PMA ( phorbol 12-myristate 13-acetate) was used to induce the differentiation of THP-1 cells into macrophages. The THP-1-derived macrophages were infected with BCG and then treated with baicalin. The expression of MICA, MICB, ULBP1 and ULBP2 at mRNA and protein levels were meas-ured by real-time PCR and Western blot assay. The BCG-infected macrophages were co-cultured with NK cells derived from human PBMC for 4 h. Real-Time Cell Analyzer ( RTCA DP) was used to evaluate the cy-totoxic activity of NK cells. Results The expression of MICA, MICB, ULBP1 and ULBP2 at mRNA level and the expression of MICA and ULBP1 at protein level were upregulated after infecting the macrophages with BCG. The expression of MICA and ULBP1 at mRNA and protein levels and the killing activity of NK cells were significantly enhanced after treating the BCG-infected macrophages with baicalin (1 mg/L) for 72 h. Conclusion BCG infection could induce the expression of NKG2D ligands on human macrophages, but could not effectively active the NK cells. Baicalin could enhance the cytotoxic activity of NK cells by further up-regulating the expression of NKG2D ligands on BCG-infected macrophages.

Objective:To compare the clinical efficacy between proximal femoral biomimetic intramedullary nail (PFBN) and traditional proximal femoral anti-rotation intramedullary nail (PFNA) in the treatment of senile osteoporotic intertrochanteric fractures.Methods:The data were retrospectively analyzed of the 92 elderly patients with osteoporotic intertrochanteric fracture who had been treated at Department of Orthopedics, People's Hospital of Xinjiang Uygur Autonomous Region from April to October in 2021. According to their internal fixation methods, the patients were divided into 2 groups.In the PFBN group of 46 patients, there were 22 males and 24 females, with an age of (75.7±5.2) years and time from injury to operation of (3.1±0.4) d; in the PFNA group of 46 patients, there were 20 males and 26 females, with an age of (75.3±4.2) years and time from injury to operation of (3.3±0.5) d. Recorded were the operation time, intraoperative blood loss, hospital stay, fracture reduction quality, postoperative weight bearing time, hip function and complications at the last follow-up.Results:There was no significant difference in the preoperative general data between the 2 groups, showing comparability ( P>0.05). The operation time in the PFBN group was (47.3±11.4) min, significantly longer than that in the PFNA group [(39.2±15.3) min] ( P<0.05); the postoperative weight-bearing time in the former was (7.9±2.7) d, significantly shorter than that in the PFNA group [(21.2±5.7) d] ( P<0.05). There were no significant differences between the 2 groups in the intraoperative blood loss [(130.6±21.3) mL versus (123.5±17.8) mL], hospital stay [(4.2±1.6) d versus (4.6±2.1) d], the excellent and good rate of Francisco score [89.1% (41/46) versus 87.0% (40/46)], fracture healing time [(12.3±0.5) weeks versus (12.6±0.7) weeks], or the excellent and good rate of Harris hip score at the last follow-up [89.1% (41/46) versus 87.0% (40/46)] (all P>0.05). Conclusion:Both PFBN and PFNA can achieve satisfactory clinical results in the treatment of osteoporotic intertrochanteric fractures in the elderly patients, but PFBN may provide more reliable early stability and reduce patient bedtime than PFNA.