Objective:To establish a normal data model of fetal right ventricular size and function using echocardiography，and to explore the clinical value of quantitative assessment of right ventricular size and function in the diagnosis of congenital heart diseases.Methods:（1）A simple random sampling method was employed to collect 1 004 pregnant women with normal singleton pregnancies at 24 to 32 +6 weeks of gestation who underwent fetal cardiac ultrasound examinations at the First Affiliated Hospital of Air Force Medical University from January 2021 to December 2023. Two-dimensional and M-mode echocardiography were used to measure the right ventricular end-diastolic diameter（RVEDD），right ventricular end-diastolic area（RVEDA），tricuspid annular plane systolic excursion（TAPSE）during systole，and the right ventricular fractional area change（RVFAC）was calculated. The correlations between the above parameters and ultrasound gestational age（USGA）were analyzed. Moreover，percentile growth curves for each parameter were plotted. With the above parameters as dependent variables and the USGA as the independent variable，a Z-score model was established through regression analysis.（2）A stratified sampling method was adopted to select 30 fetuses diagnosed with hypoplastic right heart syndrome（HRHS）and 30 fetuses diagnosed with pulmonary stenosis（PS）during the same period as the case group. The model was verified，and the morphological and functional characteristics of the right ventricle were analyzed. Results:The data of RVEDD，RVEDA，TAPSE，and RVFAC in normal fetuses showed a skewed distribution. Each parameter showed good linear correlations with USGA（ r=0.836，0.834，0.846，0.242；all P<0.001）. The constructed percentile curves for each parameter indicated that RVEDD，RVEDA and TAPSE increased significantly with the growth of USGA，while RVFAC showed a slow downward trend. All parameters in the HRHS group and TAPSE and RVFAC in the PS group deviated significantly from the normal reference range（all P<0.001）. Conclusions:By analyzing RVEDD，RVEDA，TAPSE and RVFAC of normal fetuses，the percentile and Z-score normal reference value models of multiple parameters of fetal right ventricular size and function have been established，providing corresponding standards for quantitative analysis.

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 elucidate the effects of miR-616 on the malignant biological processes of osteosarcoma and to preliminarily explore its potential mechanisms.Methods In situ hybridization(ISH)was employed to analyze miR-616 expression in 11 paraffin-embedded osteosarcoma specimens collected in our department during January 2018 to December 2019.Quantitative real-time PCR(qRT-PCR)was used to compare the mRNA expression level of miR-616 in the osteoblast cell line hFOB1.19 and osteosarcoma cell lines 143B and HOS.Stable cell lines with miR-616 knockdown or overexpression were established via lentiviral transfection in 143B and HOS cells.Cell proliferation and apoptosis were detected by flow cytometry,while cell invasion and migration were assessed using Transwell and colony formation assays,respectively.To evaluate the effect of miR-616 on tumor growth in vivo,10 female nude mice(4 weeks old,weighing 18～20 g)were randomized into a control group and a miR-616 overexpression group.After the xenograft tumor model was constructed,the growth of subcutaneous tumors was monitored.Finally,next-generation sequencing and a dual-luciferase reporter assay were performed to identify the target genes of miR-616.Results ISH results showed that miR-616 expression was up-regulated in osteosarcoma tissues than adjacent tissues,and primarily localized in the cytoplasm.qRT-PCR confirmed that miR-616 level was significantly higher in 143B and HOS cells than hFOB1.19 cells(P<0.05).In vitro experiments revealed that miR-616 overexpression enhanced the proliferation,migration and invasion,while suppressing apoptosis in 143B and HOS cells(P<0.01).Conversely,miR-616 knockdown weakened these malignant phenotypes(P<0.05),with miR-616-3p showing a stronger effect on apoptosis than miR-616-5p.Animal experiments demonstrated that the tumor weight in the miR-616 overexpression group was significantly greater than that of the control group(98.00±17.22 vs 33.60±8.08 mg,P<0.01).Furthermore,KLF2 was identified and confirmed as a direct target of miR-616.Conclusion MiR-616 promotes malignant biological behaviors in osteosarcoma,and its expression level indicates that it may serve as a potential therapeutic target.

The aim of this study is to establish an gene editing method of Mesomycoplasma hyo-pneumoniae(Mhp)based on the homologous recombination principle.The restriction enzyme di-gestion and ligation method combined with gene synthesis were used to construct a shuttle plasmid to achieve replication in both Mhp and Escherichia coli(E.coli).The pGEM?-T vector was used as the skeleton.The oriC sequence of Mhp which can achieve the replication of the plasmid in Mhp was inserted into the vector.Sequences of the Spiroplasma promoter and puromycin resistance gene were then inserted into the above constructed plasmid to screen recombinant clones.The up-stream and downstream homologous arms of p97 were constructed to initiate homologous recombination.The recA gene of E.coli is inserted to improve the efficiency of homologous recom-bination.The obtained shuttle plasmid was then delivered into Mhp by electro-transformation or chemical transformation.A shuttle plasmid,pGEM?-Mhp-oriC-p 97,which can replicate in both Mhp and E.coli was constructed.With the transformation of this plasmid,the carried puromycin gene and recA gene can be expressed,the p97 gene can be edited.Finally,the genetically unstable p97 gene mutant was initially obtained.In this study,a tool for Mhp gene editing based on the principle of homologous recombination was established,which laid a foundation for the develop-ment of tools for studying the pathogenesis of Mhp.

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.

The aim of this study is to establish an gene editing method of Mesomycoplasma hyo-pneumoniae(Mhp)based on the homologous recombination principle.The restriction enzyme di-gestion and ligation method combined with gene synthesis were used to construct a shuttle plasmid to achieve replication in both Mhp and Escherichia coli(E.coli).The pGEM?-T vector was used as the skeleton.The oriC sequence of Mhp which can achieve the replication of the plasmid in Mhp was inserted into the vector.Sequences of the Spiroplasma promoter and puromycin resistance gene were then inserted into the above constructed plasmid to screen recombinant clones.The up-stream and downstream homologous arms of p97 were constructed to initiate homologous recombination.The recA gene of E.coli is inserted to improve the efficiency of homologous recom-bination.The obtained shuttle plasmid was then delivered into Mhp by electro-transformation or chemical transformation.A shuttle plasmid,pGEM?-Mhp-oriC-p 97,which can replicate in both Mhp and E.coli was constructed.With the transformation of this plasmid,the carried puromycin gene and recA gene can be expressed,the p97 gene can be edited.Finally,the genetically unstable p97 gene mutant was initially obtained.In this study,a tool for Mhp gene editing based on the principle of homologous recombination was established,which laid a foundation for the develop-ment of tools for studying the pathogenesis of Mhp.

Objective:To establish a normal data model of fetal right ventricular size and function using echocardiography，and to explore the clinical value of quantitative assessment of right ventricular size and function in the diagnosis of congenital heart diseases.Methods:（1）A simple random sampling method was employed to collect 1 004 pregnant women with normal singleton pregnancies at 24 to 32 +6 weeks of gestation who underwent fetal cardiac ultrasound examinations at the First Affiliated Hospital of Air Force Medical University from January 2021 to December 2023. Two-dimensional and M-mode echocardiography were used to measure the right ventricular end-diastolic diameter（RVEDD），right ventricular end-diastolic area（RVEDA），tricuspid annular plane systolic excursion（TAPSE）during systole，and the right ventricular fractional area change（RVFAC）was calculated. The correlations between the above parameters and ultrasound gestational age（USGA）were analyzed. Moreover，percentile growth curves for each parameter were plotted. With the above parameters as dependent variables and the USGA as the independent variable，a Z-score model was established through regression analysis.（2）A stratified sampling method was adopted to select 30 fetuses diagnosed with hypoplastic right heart syndrome（HRHS）and 30 fetuses diagnosed with pulmonary stenosis（PS）during the same period as the case group. The model was verified，and the morphological and functional characteristics of the right ventricle were analyzed. Results:The data of RVEDD，RVEDA，TAPSE，and RVFAC in normal fetuses showed a skewed distribution. Each parameter showed good linear correlations with USGA（ r=0.836，0.834，0.846，0.242；all P<0.001）. The constructed percentile curves for each parameter indicated that RVEDD，RVEDA and TAPSE increased significantly with the growth of USGA，while RVFAC showed a slow downward trend. All parameters in the HRHS group and TAPSE and RVFAC in the PS group deviated significantly from the normal reference range（all P<0.001）. Conclusions:By analyzing RVEDD，RVEDA，TAPSE and RVFAC of normal fetuses，the percentile and Z-score normal reference value models of multiple parameters of fetal right ventricular size and function have been established，providing corresponding standards for quantitative analysis.

The widespread application of implantable materials has brought about a corresponding increase in implant-related complications, with implant-associated infections being the most critical. Biofilms, which often form on these implants, can significantly impede the effectiveness of traditional antibiotic therapies. Therefore, strategies such as surgical removal of infected implants and prolonged antibiotic treatment have been acknowledged as effective measures to eradicate these infections. However,the challenges of antibiotic resistance and biofilm persistence often result in recurrent or hard-to-control infections, posing severe health threats to patients. Recent studies suggest that phages, a type of virus, can directly eliminate pathogenic bacteria and degrade biofilms. Furthermore, clinical trials have demonstrated promising therapeutic results with the combined use of phages and antibiotics. Consequently, this innovative therapy holds significant potential as an effective solution for managing implant-associated infections. This paper rigorously investigates and evaluates the potential value of phage therapy in addressing orthopedic implant-associated infections, based on a comprehensive review of relevant scientific literature.

The widespread application of implantable materials has brought about a corresponding increase in implant-related complications, with implant-associated infections being the most critical. Biofilms, which often form on these implants, can significantly impede the effectiveness of traditional antibiotic therapies. Therefore, strategies such as surgical removal of infected implants and prolonged antibiotic treatment have been acknowledged as effective measures to eradicate these infections. However,the challenges of antibiotic resistance and biofilm persistence often result in recurrent or hard-to-control infections, posing severe health threats to patients. Recent studies suggest that phages, a type of virus, can directly eliminate pathogenic bacteria and degrade biofilms. Furthermore, clinical trials have demonstrated promising therapeutic results with the combined use of phages and antibiotics. Consequently, this innovative therapy holds significant potential as an effective solution for managing implant-associated infections. This paper rigorously investigates and evaluates the potential value of phage therapy in addressing orthopedic implant-associated infections, based on a comprehensive review of relevant scientific literature.

The widespread application of implantable materials has brought about a corresponding increase in implant-related complications, with implant-associated infections being the most critical. Biofilms, which often form on these implants, can significantly impede the effectiveness of traditional antibiotic therapies. Therefore, strategies such as surgical removal of infected implants and prolonged antibiotic treatment have been acknowledged as effective measures to eradicate these infections. However,the challenges of antibiotic resistance and biofilm persistence often result in recurrent or hard-to-control infections, posing severe health threats to patients. Recent studies suggest that phages, a type of virus, can directly eliminate pathogenic bacteria and degrade biofilms. Furthermore, clinical trials have demonstrated promising therapeutic results with the combined use of phages and antibiotics. Consequently, this innovative therapy holds significant potential as an effective solution for managing implant-associated infections. This paper rigorously investigates and evaluates the potential value of phage therapy in addressing orthopedic implant-associated infections, based on a comprehensive review of relevant scientific literature.