Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Osteoarthritis(OA)is closely related to cardiovascular disease(CVD).The incidence of CVD is signifi-cantly higher in the population of OA patients.This review first analyzes the epidemiology and common risk factors of OA and CVD,then discusses the pathogenesis of OA and CVD,and clarifies the roles of chronic low-grade in-flammation,metabolic syndrome,endothelial dysfunction,as well as macrophages,T?cells,and inflammatory fac?tors involved in the mechanisms of interaction between OA and CVD.The review further analyzes treatment strate?gies and preventive measures for OA and CVD,explores the impact of OA treatment drugs on cardiovascular safety,and elucidates the importance of cardiovascular risk assessment and management in OA patients for clinical diagno?sis and treatment.Finally,this review orientes future research directions of OA and CVD,including in?depth explo?ration of the molecular and cellular mechanisms between OA and CVD,drug interactions,and the development of new treatment strategies,aiming to provide ideas for improving the clinical diagnosis,treatment and prognosis of OA and CVD.

Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Objective:To compare the difference of LLD (leg length discrepancy) between robot-assisted and conventional methods of total hip arthroplasty (THA).Methods:Data of 38 patients who had THA performed by robot-assisted or conventional methods from January 2019 to May 2020 were retrospectively analyzed. There were 38 cases (54 hips) in robot-assisted THA group (robot group) with 18 males and 20 females (age 53.5±13.6 years, BMI 26.2±3.4 kg/m 2), and there were 21 cases (32 hips) with osteonecrosis of the femoral head, 17 cases (22 hips) with Crown typeⅠandⅡdevelopmental dysplasia of the hip. There were 38 cases (54 hips) in conventional THA group (conventional group), with 19 males and 19 females, (age 52.3±14.7 years old, BMI 25.7±2.9 kg/m 2), and there were 19 cases (30 hips) with developmental dysplasia of the hip, and 19 cases (24 hips) with osteonecrosis of the femoral head. The operative time, postoperative LLD, Harris score, forgotten joint score-12 (FJS-12) and the difference between preoperative and postoperative LLD between the two groups were compared, and the correlation between surgical methods and the change of hip length was also evaluated. Results:The operation time of the robot group was 73.3±14.1 min and which was 59.3±12.6 min in conventional THA group ( t=2.732, P=0.003). In the robot group, the postoperative LLD was 2.3±3.4 mm, which was less than that of the conventional group 6.7±5.4 mm ( t=3.521, P < 0.001). When the absolute value of LLD was larger than 5 mm as an abnormal value, it was 2.6% (1/38) in the robot group and 47.3% (18/38) in the conventional group. The difference of hip length (HL) in planning and post-operation in the robot group was 2.8±2.2 mm, which was smaller than that in the conventional THA group 7.9±5.3 mm ( t=2.357, P < 0.001). In addition, there was a correlation between the change of hip length results and the postoperative measurement of hip length in the robot group ( r=0.983, P < 0.001). At the last follow-up, Harris score and FJS-12 were recorded in the robot group and coventional group. The scores were 83.1±5.3 and 32.5±4.9 respectively in the robot group, 82.9±7.2 and 31.9±6.7 in the conventional group, respectively. There was no significant difference between the two groups ( t=0.221, 0.356; P=0.819, 0.731). Postoperative bleeding occurred in 1 case in the robot group with postoperative suture healed well. The fracture of the posterior wall of the acetabulum was found in the conventional group and the patient avoids weight bearing 4 weeks after operation. The postoperative recovery was good and no other related complications were found. Conclusion:Robot-assisted THA can accurately restore the length of both legs and reduce LLD compared with conventional THA. The real-time monitoring of LLD during robot operation can give the operator an accurate reference.

Objective To construct the eukaryotic expression vector of cyclin-dependent kinase ( CDK) 7 labeled with Myc tag, obtain the expressed product , and identify its interaction with FLAG-P53 at the protein level .Methods Human CDK7 coding gene region amplified from the mammary cDNA library by PCR was inserted into the pXJ -40 vector.The recombinant plasmid Myc-CDK7 transfected into human 293T cell lines was investigated and examined by SDS-PAGE and Western blotting.In addition,assay was applied to determine the interaction between Myc-CDK7 and FLAG-p53.Results The coding region of CDK7 was successfully amplified by PCR and cloned into pXJ-40 vector, which was identified by double enzyme digestion and gene sequencing .Myc-CDK7 was successfully expressed in human 293T cell lines according to SDS-PAGE and Western blotting assay indicated that Myc-CDK7 could interact with P53 protein, which verified its known function .Conclusion The eukaryotic expression vector Myc-CDK7 is successfully obtained , which will contribute to further research on CDK 7-mediated cell cycle regulation .

Objective To construct the prokaryotic expression vector of human autophagy-related LC3B gene,obtain the GST-LC3B recombinant plasmid , purify the GST-LC3B fusion protein and identify its activity in vitro.Methods Human LC3B coding region was amplified from the human mammary gland cDNA by PCR and inserted into the prokaryotic expres -sion vector pGEX-KG.The recombinant plasmid pGEX-KG-LC3B was transformed into E.coli Rossate.The expressed product was purified by GST-Sepharose 4B beads and identified by SDS-PAGE and Western blot analysis .The function of the purified protein GST-LC3B was detected by GST pull-down assay.Results About 400 bp of the LC3B coding region was successfully amplified from the mammary gland library by PCR and inserted into pGEX -KG.The result of double diges-tion and sequencing showed that the GST-LC3B recombinant plasmid was successfully obtained .The GST-LC3B fusion pro-tein of about 40 000 (Mr) was successfully purified and identified by SDS-PAGE and Western blotting analysis.GST pull-down assay showed that GST-LC3B could interact with Atg4B, which identified its known function .Conclusion The pro-karyotic expression vector of GST-LC3B is constructed successfully , which will facilitate further research on the function of LC3B in autophagy.