Objective:To assess the status of undernutrition and appropriate catch-up growth in extremely preterm infants within 24 months of corrected age (CA).Methods:A retrospective cohort study was conducted. A total of 422 extremely preterm infants born at Shenzhen Maternity and Child Healthcare Hospital, Women and Children's Medical Center, Southern Medical University from January 2017 to December 2022 and followed up until 24 months of CA were enrolled. The extremely preterm infants were grouped by gestational age at birth (<25, 25-26, 27 weeks), birth weight (<500, 500-749, 750-999,≥1 000 g), weight for gestational age (large for gestational age (LGA), appropriate for gestational age (AGA), small for gestational age (SGA)) and sex. Weight data within 24 months of CA were collected every 3 months. Nutritional insufficiency, growth rate, and achievement of adequate catch-up growth were analyzed during the period from 0 to 24 months of CA. Z-score method was used to analyze data. Fenton 2013 preterm growth charts (Fenton 2013) were used before 40 weeks of corrected gestational age, and World Health Organization child growth standards (2009) fitted Z-scores were applied from 40 weeks of CA. Changes in weight Z-scores of extremely preterm infants from 0 to 24 months of CA were observed and compared, the occurrence of moderate to severe malnutrition and growth retardation was determined, nutritional insufficiency was assessed, and growth rate as well as the achievement of appropriate catch-up growth were analyzed. The Lambda-mu-sigma method combined with the Z-score fitting model was used to fit and analyze the distribution characteristics of weight percentiles in extremely preterm infants. The Chi-square test was used to compare differences among groups.Results:A total of 422 extremely preterm infants were included, with a gestational age at birth of 26.3(25.4, 27.2) weeks and a birth weight of (880±177) g. Among them, 238 were males and 184 were females; 36 cases (8.5%) were LGA, and 16 cases (3.8%) were SGA. During follow-up within 24 month of CA, 89 cases (21.1%) developed moderate to severe malnutrition. When compared separately among different birth weight and gestational age at birth groups, there had both statistically differences in the incidence of moderate to severe malnutrition ( χ2=42.94 and 9.17, both P<0.05). The incidence was the highest in the birth weight of CA<500 g group and the <25 weeks gestational age at birth group, while it was the lowest in the birth weight of CA≥1 000 g group and the 27 weeks gestational age at birth group in their respective groups. Growth retardation occurred in 5.2% (22/422). However, there had statistically differences in the incidence of growth retardation among different birth weight and gestational age at birth groups, in each grouped time interval ( χ2=21.61 and 4.30, both P<0.05). The proportions of rapid growth were relatively high in the 0-3 months and 3-6 months of CA groups, which were 96 cases (27.4%) and 98 cases (26.6%), respectively. Overall, appropriate catch-up growth was achieved in 341 cases (80.8%) from 0 to 24 months of CA. There had statistically differences in the completion rate of appropriate catch-up growth among different birth weight and gestational age at birth groups ( χ2=23.65 and 7.08, both P<0.05). The completion rate was the highest in the birth weight of CA<500 g group and the <25 weeks of gestational age at birth group, while it was the lowest in the birth weight of CA≥1 000 g group and the 27 weeks of gestational age at birth group. Conclusions:The lower the birth weight and gestational age of extremely preterm infants, the higher the incidence of moderate to severe malnutrition and the lower the achievement rate of adequate catch-up growth within 24 months of CA. The period of 0-6 months of CA is the critical window for catch-up in extremely preterm infants.

Objective:To assess the status of undernutrition and appropriate catch-up growth in extremely preterm infants within 24 months of corrected age (CA).Methods:A retrospective cohort study was conducted. A total of 422 extremely preterm infants born at Shenzhen Maternity and Child Healthcare Hospital, Women and Children's Medical Center, Southern Medical University from January 2017 to December 2022 and followed up until 24 months of CA were enrolled. The extremely preterm infants were grouped by gestational age at birth (<25, 25-26, 27 weeks), birth weight (<500, 500-749, 750-999,≥1 000 g), weight for gestational age (large for gestational age (LGA), appropriate for gestational age (AGA), small for gestational age (SGA)) and sex. Weight data within 24 months of CA were collected every 3 months. Nutritional insufficiency, growth rate, and achievement of adequate catch-up growth were analyzed during the period from 0 to 24 months of CA. Z-score method was used to analyze data. Fenton 2013 preterm growth charts (Fenton 2013) were used before 40 weeks of corrected gestational age, and World Health Organization child growth standards (2009) fitted Z-scores were applied from 40 weeks of CA. Changes in weight Z-scores of extremely preterm infants from 0 to 24 months of CA were observed and compared, the occurrence of moderate to severe malnutrition and growth retardation was determined, nutritional insufficiency was assessed, and growth rate as well as the achievement of appropriate catch-up growth were analyzed. The Lambda-mu-sigma method combined with the Z-score fitting model was used to fit and analyze the distribution characteristics of weight percentiles in extremely preterm infants. The Chi-square test was used to compare differences among groups.Results:A total of 422 extremely preterm infants were included, with a gestational age at birth of 26.3(25.4, 27.2) weeks and a birth weight of (880±177) g. Among them, 238 were males and 184 were females; 36 cases (8.5%) were LGA, and 16 cases (3.8%) were SGA. During follow-up within 24 month of CA, 89 cases (21.1%) developed moderate to severe malnutrition. When compared separately among different birth weight and gestational age at birth groups, there had both statistically differences in the incidence of moderate to severe malnutrition ( χ2=42.94 and 9.17, both P<0.05). The incidence was the highest in the birth weight of CA<500 g group and the <25 weeks gestational age at birth group, while it was the lowest in the birth weight of CA≥1 000 g group and the 27 weeks gestational age at birth group in their respective groups. Growth retardation occurred in 5.2% (22/422). However, there had statistically differences in the incidence of growth retardation among different birth weight and gestational age at birth groups, in each grouped time interval ( χ2=21.61 and 4.30, both P<0.05). The proportions of rapid growth were relatively high in the 0-3 months and 3-6 months of CA groups, which were 96 cases (27.4%) and 98 cases (26.6%), respectively. Overall, appropriate catch-up growth was achieved in 341 cases (80.8%) from 0 to 24 months of CA. There had statistically differences in the completion rate of appropriate catch-up growth among different birth weight and gestational age at birth groups ( χ2=23.65 and 7.08, both P<0.05). The completion rate was the highest in the birth weight of CA<500 g group and the <25 weeks of gestational age at birth group, while it was the lowest in the birth weight of CA≥1 000 g group and the 27 weeks of gestational age at birth group. Conclusions:The lower the birth weight and gestational age of extremely preterm infants, the higher the incidence of moderate to severe malnutrition and the lower the achievement rate of adequate catch-up growth within 24 months of CA. The period of 0-6 months of CA is the critical window for catch-up in extremely preterm infants.

Health economics evidence plays an important role in linking clinical value evidence with health resource allocation decisions in the development of clinical practice guidelines. It can not only effectively balance clinical effectiveness and economic feasibility but also avoid forming "idealized" recommendations that are detached from the affordability of the healthcare system or the burden-bearing capacity of patients. To promote guideline developers to use health economics evidence more standardizedly and fully, this paper conducts an in-depth analysis of the current application status, existing challenges, access channels, and application processes of health economics evidence in current guidelines, and on this basis, puts forward considerations and suggestions for strengthening and standardizing the application of health economics evidence in China's clinical practice guidelines.

Tumor drug resistance is an important problem in the failure of chemotherapy and targeted drug therapy, which is a complex process involving chromatin remodeling. SWI/SNF is one of the most studied ATP-dependent chromatin remodeling complexes in tumorigenesis, which plays an important role in the coordination of chromatin structural stability, gene expression, and post-translation modification. However, its mechanism in tumor drug resistance has not been systematically combed. SWI/SNF can be divided into 3 types according to its subunit composition: BAF, PBAF, and ncBAF. These 3 subtypes all contain two mutually exclusive ATPase catalytic subunits (SMARCA2 or SMARCA4), core subunits (SMARCC1 and SMARCD1), and regulatory subunits (ARID1A, PBRM1, and ACTB, etc.), which can control gene expression by regulating chromatin structure. The change of SWI/SNF complex subunits is one of the important factors of tumor drug resistance and progress. SMARCA4 and ARID1A are the most widely studied subunits in tumor drug resistance. Low expression of SMARCA4 can lead to the deletion of the transcription inhibitor of the BCL2L1 gene in mantle cell lymphoma, which will result in transcription up-regulation and significant resistance to the combination therapy of ibrutinib and venetoclax. Low expression of SMARCA4 and high expression of SMARCA2 can activate the FGFR1-pERK1/2 signaling pathway in ovarian high-grade serous carcinoma cells, which induces the overexpression of anti-apoptosis gene BCL2 and results in carboplatin resistance. SMARCA4 deletion can up-regulate epithelial-mesenchymal transition (EMT) by activating YAP1 gene expression in triple-negative breast cancer. It can also reduce the expression of Ca²⁺ channel IP3R3 in ovarian and lung cancer, resulting in the transfer of Ca²⁺ needed to induce apoptosis from endoplasmic reticulum to mitochondria damage. Thus, these two tumors are resistant to cisplatin. It has been found that verteporfin can overcome the drug resistance induced by SMARCA4 deletion. However, this inhibitor has not been applied in clinical practice. Therefore, it is a promising research direction to develop SWI/SNF ATPase targeted drugs with high oral bioavailability to treat patients with tumor resistance induced by low expression or deletion of SMARCA4. ARID1A deletion can activate the expression of ANXA1 protein in HER2+ breast cancer cells or down-regulate the expression of progesterone receptor B protein in endometrial cancer cells. The drug resistance of these two tumor cells to trastuzumab or progesterone is induced by activating AKT pathway. ARID1A deletion in ovarian cancer can increase the expression of MRP2 protein and make it resistant to carboplatin and paclitaxel. ARID1A deletion also can up-regulate the phosphorylation levels of EGFR, ErbB2, and RAF1 oncogene proteins.The ErbB and VEGF pathway are activated and EMT is increased. As a result, lung adenocarcinoma is resistant to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). Although great progress has been made in the research on the mechanism of SWI/SNF complex inducing tumor drug resistance, most of the research is still at the protein level. It is necessary to comprehensively and deeply explore the detailed mechanism of drug resistance from gene, transcription, protein, and metabolite levels by using multi-omics techniques, which can provide sufficient theoretical basis for the diagnosis and treatment of poor tumor prognosis caused by mutation or abnormal expression of SWI/SNF subunits in clinical practice.

Objective To investigate the mechanism of action of the nuclear factor erythroid 2-related factor 2(Nrf2)/solute carrier family 7 member 11(SLC7A11)/glutathione peroxidase 4(GPX4)signaling pathway in non-alcoholic fatty liver disease(NAFLD),and to explore the mechanism of Gegen QinLian Decoction for the treatment of NAFLD,using in vivo and in vitro experiments.Methods Rats were fed with high-fat chow for 24 weeks to induce NAFLD,and were then divided randomly into normal(C),model(M),high-,medium-,and low-dose Gegen QinLian Decoction(GGQLT-H,GGQLT-M,GGQLT-L),and metformin(Met)groups.From week 25 onwards,the rats were administered the corresponding drugs by gavage for 2 weeks according to the grouping,until sampling.Levels of the oxidative stress markers malondialdehyde(MDA)and glutathione(GSH)in the liver tissues were measured in each group using biochemical kits and ferrous iron(Fe2+)in rat liver tissues was detected using a Fe2+kit.Nrf2,heme oxygenase-1(HO-1),SLC7A11,glutathione synthetase(GSS),GPX4,and acyl coenzyme A synthetase 4(ACSL4)mRNA levels in rat liver tissues were measured by reverse transcription quantitative polymerase chain reaction.For cellular experiments lipid acc umulation was induced in HepG2 hepatocellular carcinoma cells using 1 mmol/L free fatty acid,to mimic the NAFLD in vitro model.Different concentrations of Gegen QinLian Decoction and metformin-containing serum were added for treatment.Lipid accumulation was detected in the cells in each group by Oil red O staining.The MDA and GSH contents of HepG2 cells in the different groups were determined using appropriate kits,and the ferrous contents were detected using a cell-specific ferrous kit.Expression levels of Nrf2,HO-1,SLC7A11,GSS,GPX4,and ACSL4 mRNA was detected in each group of cells using reverse transcription quantitative polymerase chain reaction.Results In the animal experiments,MDA and Fe2+liver levels were significantly higher in the M group than in the C group,while GSH levels were significantly lower(P＜0.01).GGQLT-H,GGQLT-M and Met groups showed significantly reduced MDA and Fe2+and elevated GSH levels compared with the M group(P＜0.01,P＜0.05).High-and medium-dose Gegen QinLian Decoction and metformin increased Nrf2,HO-1,GSS,and GPX4 mRNA and decreased ACSL4 mRNA expression levels(P＜0.01,P＜0.05).In cellular experiments,lipid droplets were significantly increased in the HepG2 cell M group compared with those in the C group,and lipid droplets were significantly reduced by Gegen QinLian Decoction and metformin.MDA and Fe2+levels were significantly increased and GSH levels were significantly decreased in the HepG2 M group compared with the levels in the C group(P＜0.01),while all doses of Gegen QinLian Decoction and metformin significantly decreased MDA and Fe2+levels(P＜0.01)and increased the GSH content(P＜0.01,P＜0.05).Nrf2,GSS,GPX4,and SLC7A11 mRNA expression levels in the GGQLT-H group,Nrf2,HO-1,and SLC7A11 in the GGQLT-L group,HO-1,SLC7A11,and GSS in the GGQLT-M group,and GSS,Nrf2,and HO-1 in the Met group were all significantly increased compared with the findings in the M group(P＜0.01,P＜0.05).ACSL4 mRNA expression levels were significantly decreased in the GGQLT-M and GGQLT-L groups and the Met group(P＜0.01,P＜0.05).Conclusions Gegen QinLian Decoction can improve NAFLD by inhibiting ferroptosis,and its mechanism may he related to regulation of the Nrf2/SLC7A 11/GPX4 signaling pathway.

To formulate an expert consensus on the principles of preoperative hair removal and provide scientific guidance for standardized removal of hair before surgical procedures so as to reduce the incidence of surgical site infections.METHODS Led by the Hospital Management Institute of National Health Commission of the People's Republic of China,this consensus was reached with the joint efforts from the expects of relevant fields such as surgeries,interventional therapies,nursing,and infection prevention and control.The consensus facilitates the classification and evaluation of literatures by following the evidence grade formulated by Oxford Evidence-based Medicine Center and focuses on the association of preoperative hair removal with surgical site infection,it reaches the evidence grade of expert consensus and recommendation intensity by integrating with discussions on meetings and clinical experience of the expects from relevant fields.RESULTS A total of 6 items of consensus were reached by summarizing the latest evidence on the aspects including the indications for preoperative hair removal,tools,range,timing and places.CONCLUSION The consensus,to some extent,make supplements to and complete the exiting regulations and standards.It provides guidance for the medical institutions to carry out the preoperative hair removal.

Electroencephalogram (EEG) is a non-invasive, high temporal-resolution technique for monitoring brain activity. However, affected by the volume conduction effect, EEG has a low spatial resolution and is difficult to locate brain neuronal activity precisely. The surface Laplacian (SL) technique obtains the Laplacian EEG (LEEG) by estimating the second-order spatial derivative of the scalp potential. LEEG can reflect the radial current activity under the scalp, with positive values indicating current flow from the brain to the scalp (“source”) and negative values indicating current flow from the scalp to the brain (“sink”). It attenuates signals from volume conduction, effectively improving the spatial resolution of EEG, and is expected to contribute to breakthroughs in neural engineering. This paper provides a systematic overview of the principles and development of SL technology. Currently, there are two implementation paths for SL technology: current source density algorithms (CSD) and concentric ring electrodes (CRE). CSD performs the Laplace transform of the EEG signals acquired by conventional disc electrodes to indirectly estimate the LEEG. It can be mainly classified into local methods, global methods, and realistic Laplacian methods. The global method is the most commonly used approach in CSD, which can achieve more accurate estimation compared with the local method, and it does not require additional imaging equipment compared with the realistic Laplacian method. CRE employs new concentric ring electrodes instead of the traditional disc electrodes, and measures the LEEG directly by differential acquisition of the multi-ring signals. Depending on the structure, it can be divided into bipolar CRE, quasi-bipolar CRE, tripolar CRE, and multi-pole CRE. The tripolar CRE is widely used due to its optimal detection performance. While ensuring the quality of signal acquisition, the complexity of its preamplifier is relatively acceptable. Here, this paper introduces the study of the SL technique in resting rhythms, visual-related potentials, movement-related potentials, and sensorimotor rhythms. These studies demonstrate that SL technology can improve signal quality and enhance signal characteristics, confirming its potential applications in neuroscientific research, disease diagnosis, visual pathway detection, and brain-computer interfaces. CSD is frequently utilized in applications such as neuroscientific research and disease detection, where high-precision estimation of LEEG is required. And CRE tends to be used in brain-computer interfaces, that have stringent requirements for real-time data processing. Finally, this paper summarizes the strengths and weaknesses of SL technology and envisages its future development. SL technology boasts advantages such as reference independence, high spatial resolution, high temporal resolution, enhanced source connectivity analysis, and noise suppression. However, it also has shortcomings that can be further improved. Theoretically, simulation experiments should be conducted to investigate the theoretical characteristics of SL technology. For CSD methods, the algorithm needs to be optimized to improve the precision of LEEG estimation, reduce dependence on the number of channels, and decrease computational complexity and time consumption. For CRE methods, the electrodes need to be designed with appropriate structures and sizes, and the low-noise, high common-mode rejection ratio preamplifier should be developed. We hope that this paper can promote the in-depth research and wide application of SL technology.

Middle compartment defects,a common subtype of pelvic floor dysfunction(PFD),are primarily characterized by the prolapse of the uterus or vaginal vault.Magnetic resonance imaging(MRI)has emerged as a valuable diagnostic tool for PFD,offering superior soft tissue resolution while eliminating exposure to ionizing radiation.This review comprehensive summarizes current applications of MRI in the diagnosis and treatment of PFD,covering measurement methods,manifestations of three-level structural defects,postoperative efficacy evaluation,vaginal axial assessment,and evaluation of the mesh status.The authors suggest that MRI enables precise preoperative evaluation of three-level defects,thereby facilitating the development of personalized treatment plans.Additionally,MRI provides an accurate postoperative assessment of surgical outcomes and mesh status,offering a new basis for postoperative assessment.MRI demonstrates unique value in the diagnosis and treatment of middle compartment defects.

Objective To investigate the mechanism of action of the nuclear factor erythroid 2-related factor 2(Nrf2)/solute carrier family 7 member 11(SLC7A11)/glutathione peroxidase 4(GPX4)signaling pathway in non-alcoholic fatty liver disease(NAFLD),and to explore the mechanism of Gegen QinLian Decoction for the treatment of NAFLD,using in vivo and in vitro experiments.Methods Rats were fed with high-fat chow for 24 weeks to induce NAFLD,and were then divided randomly into normal(C),model(M),high-,medium-,and low-dose Gegen QinLian Decoction(GGQLT-H,GGQLT-M,GGQLT-L),and metformin(Met)groups.From week 25 onwards,the rats were administered the corresponding drugs by gavage for 2 weeks according to the grouping,until sampling.Levels of the oxidative stress markers malondialdehyde(MDA)and glutathione(GSH)in the liver tissues were measured in each group using biochemical kits and ferrous iron(Fe2+)in rat liver tissues was detected using a Fe2+kit.Nrf2,heme oxygenase-1(HO-1),SLC7A11,glutathione synthetase(GSS),GPX4,and acyl coenzyme A synthetase 4(ACSL4)mRNA levels in rat liver tissues were measured by reverse transcription quantitative polymerase chain reaction.For cellular experiments lipid acc umulation was induced in HepG2 hepatocellular carcinoma cells using 1 mmol/L free fatty acid,to mimic the NAFLD in vitro model.Different concentrations of Gegen QinLian Decoction and metformin-containing serum were added for treatment.Lipid accumulation was detected in the cells in each group by Oil red O staining.The MDA and GSH contents of HepG2 cells in the different groups were determined using appropriate kits,and the ferrous contents were detected using a cell-specific ferrous kit.Expression levels of Nrf2,HO-1,SLC7A11,GSS,GPX4,and ACSL4 mRNA was detected in each group of cells using reverse transcription quantitative polymerase chain reaction.Results In the animal experiments,MDA and Fe2+liver levels were significantly higher in the M group than in the C group,while GSH levels were significantly lower(P＜0.01).GGQLT-H,GGQLT-M and Met groups showed significantly reduced MDA and Fe2+and elevated GSH levels compared with the M group(P＜0.01,P＜0.05).High-and medium-dose Gegen QinLian Decoction and metformin increased Nrf2,HO-1,GSS,and GPX4 mRNA and decreased ACSL4 mRNA expression levels(P＜0.01,P＜0.05).In cellular experiments,lipid droplets were significantly increased in the HepG2 cell M group compared with those in the C group,and lipid droplets were significantly reduced by Gegen QinLian Decoction and metformin.MDA and Fe2+levels were significantly increased and GSH levels were significantly decreased in the HepG2 M group compared with the levels in the C group(P＜0.01),while all doses of Gegen QinLian Decoction and metformin significantly decreased MDA and Fe2+levels(P＜0.01)and increased the GSH content(P＜0.01,P＜0.05).Nrf2,GSS,GPX4,and SLC7A11 mRNA expression levels in the GGQLT-H group,Nrf2,HO-1,and SLC7A11 in the GGQLT-L group,HO-1,SLC7A11,and GSS in the GGQLT-M group,and GSS,Nrf2,and HO-1 in the Met group were all significantly increased compared with the findings in the M group(P＜0.01,P＜0.05).ACSL4 mRNA expression levels were significantly decreased in the GGQLT-M and GGQLT-L groups and the Met group(P＜0.01,P＜0.05).Conclusions Gegen QinLian Decoction can improve NAFLD by inhibiting ferroptosis,and its mechanism may he related to regulation of the Nrf2/SLC7A 11/GPX4 signaling pathway.

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.