BACKGROUND:Periprosthetic joint infection is the most common cause of early failure after total knee replacement.The current methods of preventing periprosthetic joint infection by improving the surface of the prosthesis have limitations to varying degrees.OBJECTIVE:To construct a coating material that can stably improve the surface of the implant,prevent the initial floating bacterial infection of periprosthetic infection,and regulate the bone transfer function around the implant.METHODS:(1)Material preparation:YGF polypeptide(which promotes bone formation),LL-37 polypeptide(with antibacterial properties)and YGF+LL-37 composite peptide were prepared by Fmoc solid phase peptide synthesis technology.The titanium-based materials were immersed in the three polypeptide solutions for 2 hours to obtain YGF coating,LL-37 coating and composite peptide coating coated titanium sheets.(2)In vitro experiment:Uncoated titanium sheets and coated titanium sheets were co-cultured with Escherichia coli(or Staphylococcus aureus)and the colonies were counted by plate method.MC3T3 cells were inoculated on the surface of uncoated titanium sheet and coated titanium sheet,respectively.Alizarin red staining was used to observe the calcium salt deposition on the surface of the material.Western blot assay was used to detect the protein expression of RUNX2,osteocalcin,osteopontin,and bone morphogenetic protein 2.(3)Animal experiment:24 SD rats were randomly divided into three groups:the blank group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal;the control group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension;the experimental group(n=8)was implanted with composite peptide coated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension.After 5 weeks of implantation,micro-CT examination,hematoxylin-eosin staining and immunohistochemical staining of femur specimens were performed.RESULTS AND CONCLUSION:(1)In vitro experiment:Compared with uncoated titanium sheet and YGF coated titanium sheet,LL-37 coated and composite peptide coated titanium sheet could significantly inhibit the growth and reproduction of Escherichia coli and Staphylococcus aureus.Compared with uncoated titanium sheets and LL-37-coated titanium sheets,YGF-coated and composite peptide-coated titanium sheets could promote calcium salt deposition in osteoblasts and increase the protein expression of RUNX2,osteocalcin,osteopontin and bone morphogenetic protein 2.(2)Animal experiment:Micro-CT test showed that the control group had less bone mass than the blank group and the experimental group.Hematoxylin-eosin staining showed that there was a large amount of fibrous tissue around the nail channel in the control group,only a small amount of tissue fibrosis around the nail channel in the blank group,and only a small amount of tissue fibrosis around the nail channel in the experimental group.Immunohistochemical staining showed that the protein expression of interleukin 1β and tumor necrosis factor α in the control group was higher than that in the blank group and the experimental group,and the expression of osteocalcin,RUNX2 and osteopontin in the experimental group was higher than that in the blank group and the control group.(3)The results show that the titanium-based material coated with YGF+LL-37 composite peptide coating has good antibacterial ability and can promote bone transfer around the implant.

BACKGROUND:Periprosthetic joint infection is the most common cause of early failure after total knee replacement.The current methods of preventing periprosthetic joint infection by improving the surface of the prosthesis have limitations to varying degrees.OBJECTIVE:To construct a coating material that can stably improve the surface of the implant,prevent the initial floating bacterial infection of periprosthetic infection,and regulate the bone transfer function around the implant.METHODS:(1)Material preparation:YGF polypeptide(which promotes bone formation),LL-37 polypeptide(with antibacterial properties)and YGF+LL-37 composite peptide were prepared by Fmoc solid phase peptide synthesis technology.The titanium-based materials were immersed in the three polypeptide solutions for 2 hours to obtain YGF coating,LL-37 coating and composite peptide coating coated titanium sheets.(2)In vitro experiment:Uncoated titanium sheets and coated titanium sheets were co-cultured with Escherichia coli(or Staphylococcus aureus)and the colonies were counted by plate method.MC3T3 cells were inoculated on the surface of uncoated titanium sheet and coated titanium sheet,respectively.Alizarin red staining was used to observe the calcium salt deposition on the surface of the material.Western blot assay was used to detect the protein expression of RUNX2,osteocalcin,osteopontin,and bone morphogenetic protein 2.(3)Animal experiment:24 SD rats were randomly divided into three groups:the blank group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal;the control group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension;the experimental group(n=8)was implanted with composite peptide coated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension.After 5 weeks of implantation,micro-CT examination,hematoxylin-eosin staining and immunohistochemical staining of femur specimens were performed.RESULTS AND CONCLUSION:(1)In vitro experiment:Compared with uncoated titanium sheet and YGF coated titanium sheet,LL-37 coated and composite peptide coated titanium sheet could significantly inhibit the growth and reproduction of Escherichia coli and Staphylococcus aureus.Compared with uncoated titanium sheets and LL-37-coated titanium sheets,YGF-coated and composite peptide-coated titanium sheets could promote calcium salt deposition in osteoblasts and increase the protein expression of RUNX2,osteocalcin,osteopontin and bone morphogenetic protein 2.(2)Animal experiment:Micro-CT test showed that the control group had less bone mass than the blank group and the experimental group.Hematoxylin-eosin staining showed that there was a large amount of fibrous tissue around the nail channel in the control group,only a small amount of tissue fibrosis around the nail channel in the blank group,and only a small amount of tissue fibrosis around the nail channel in the experimental group.Immunohistochemical staining showed that the protein expression of interleukin 1β and tumor necrosis factor α in the control group was higher than that in the blank group and the experimental group,and the expression of osteocalcin,RUNX2 and osteopontin in the experimental group was higher than that in the blank group and the control group.(3)The results show that the titanium-based material coated with YGF+LL-37 composite peptide coating has good antibacterial ability and can promote bone transfer around the implant.

Stroke, a major cerebrovascular disease, has high morbidity and mortality. Effective methods to reduce the risk and improve the prognosis are lacking. Currently, uric acid (UA) is associated with the pathological mechanism, prognosis, and therapy of stroke. UA plays pro/anti-oxidative and pro-inflammatory roles in vivo. The specific role of UA in stroke, which may have both neuroprotective and damaging effects, remains unclear. There is a U-shaped association between serum uric acid (SUA) levels and ischemic stroke (IS). UA therapy provides neuroprotection during reperfusion therapy for acute ischemic stroke (AIS). Urate-lowering therapy (ULT) plays a protective role in IS with hyperuricemia or gout. SUA levels are associated with the cerebrovascular injury mechanism, risk, and outcomes of hemorrhagic stroke. In this review, we summarize the current research on the role of UA in stroke, providing potential targets for its prediction and treatment.
Humans ; Uric Acid/metabolism* ; Stroke/drug therapy* ; Animals ; Hyperuricemia/drug therapy* ; Ischemic Stroke/blood* ; Biomarkers/blood*

Objective:To optimize the image quality of PET/CT following 90Y-selective internal radiation therapy ( 90Y-SIRT) using block-sequential regularized expectation maximization (BSREM) reconstruction algorithm, and to evaluate its impact of different β values on image quality and quantitative analysis. Methods:A retrospective study was conducted on 8 male patients with hepatic tumors (age: 62(52, 71) years) treated at Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua Medicine Tsinghua University, between June 2024 and January 2025. All patients were treated with 90Y resin microspheres (2.6(0.9, 3.6)GBq) and underwent post-treatment 90Y PET/CT liver imaging. Imaging data were reconstructed using BSREM with different noise penalty weighting factors ( β values: 0, 300, 1000, 1500, 2500, 3500, 4000, 6000, 8000, 10000). Visual assessment was independently performed by two nuclear medicine physicians, using a 4-point scale (1=worst, 4=best). The mean score was considered as the final score. The consistency of the 2 reviewers was calculated and analyzed by Kappa test. Visual scores of different β value groups were compared by Friedman test. The β value demonstrating highest mean score and optimal consistency was selected as the optimal. Quantitative analysis was performed using MIM software to calculate the maximum absorbed dose ( Dmax) and the mean absorbed dose ( Dmean) for tumor, normal liver, and whole liver regions, and the CV was used to evaluate the impact of β values. Results:The visual assessment consistency of reviewers in 3 β value groups (0, 3500, 6000) were the highest (7/8) (all kappa=0.88, all P<0.05). Visual scores of the 10 β value groups were significantly different ( χ2=28.74, P<0.001), and the visual scores of 2 β value groups (3500, 4000) were the highest, both of which were 4.0(4.0, 4.0). Overall, visual assessment identified β=3500 as the optimal. Quantitative analysis revealed that, (1) Dmax in all regions (tumor, normal liver, whole liver) decreased with the increasing β values, stabilizing when β>1000 ( CV 56%-67%); (2) Dmean remained stable across different β values ( CV 0.04%-5.00%). Conclusions:In BSREM reconstruction, β=3500 is the optimal parameter for improving 90Y-PET image quality. β values significantly affect Dmax (stabilizing at β > 1000), but have no significant impact on Dmean, suggesting that reconstruction parameters primarily influence dose distribution morphology rather than average dose assessments.

Objective:To evaluate the clinical efficacy of intervertebral disc radiofrequency(RF)ablation combined with dorsal medial branch(DMB)neurotomy in elderly patients suffering from chronic low back pain.Methods:A retrospective analysis was conducted on patients aged 60 years and older with chronic low back pain admitted to Beijing Hospital from March 2023 to September 2024.The combined treatment group underwent intervertebral disc radiofrequency ablation combined with radiofrequency treatment of the dorsal medial branch of the spinal nerve.The single treatment group underwent intervertebral disc radiofrequency ablation alone.Pain visual analogue scale(VAS)scores were assessed before treatment and on the first day, 3 months, and 6 months post-treatment.The Oswestry Disability Index(ODI)and Barthel Index were evaluated before treatment and at 3 months and 6 months post-treatment.Clinical efficacy was compared between the two groups.Results:A total of 115 elderly patients with chronic low back pain were enrolled, aged 61 to 72 years(mean 66.5 ± 5.6 years), with 44 males.The combined therapy group consisted of 71 patients, and the monotherapy group consisted of 44 patients.All patients were followed up continuously for 6 months.At all-time points post-treatment, the VAS scores in the combined therapy group were significantly lower than those in the monotherapy group( t=-4.887, -10.095, -7.687, all P<0.05); at 3 and 6 months post-treatment, the combined therapy group showed significantly greater improvements in ODI( t=-3.645, -9.451, both P<0.001)Barthel Index improvement were significantly greater than those in the monotherapy group( t=6.578, 8.530, both P<0.001); the overall good-to-excellent rate in the combined therapy group was 88.7%, higher than the 72.7% in the monotherapy group( χ2=4.85, P<0.05). Conclusions:Combined disc RF ablation and DMB neurotomy provide superior pain relief, functional recovery, and improvement in daily activities compared to single disc ablation in elderly patients with CLBP.This minimally invasive approach represents a safe and effective therapeutic strategy for managing chronic low back pain in the geriatric population.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Objective:To analyze the awareness of HCV infection status and willingness for HCV-RNA testing among hepatitis C cases in four provinces in China and to provide a reference for adjusting HCV prevention and control strategies.Methods:From September 2021 to September 2022, a cross-sectional survey was conducted using stratified random cluster sampling in four provinces (Jiangsu, Henan, Hubei, and Yunnan) in China, with an estimated sample size of 6 468 participants. The questionnaire included sociodemographic information, HCV infection awareness, willingness for HCV-RNA testing, and history of high-risk behaviors from the survey participants. Logistic regression models were used to analyze the factors associated with HCV infection awareness and willingness for HCV-RNA testing among hepatitis C cases. Statistical analysis was performed using R 4.1.3 software.Results:A total of 10 563 hepatitis C cases were surveyed. The awareness rate of HCV infection was 86.74% (9 162/10 563), and the willingness rate for HCV-RNA testing was 85.21% (9 001/10 563). Multivariate logistic regression models analysis showed that the awareness rate of HCV infection was lower among individuals aged ≥60 years, urban residents (with New Rural Cooperative Medical Insurance ), those without a history of blood transfusion, those without a history of paid blood donation, those without a history of injection drug use, and those without a family member with hepatitis C case.The awareness rate was higher among individuals with high or technical secondary school education, college education or above, and those married with a spouse (all P<0.05). In terms of willingness for HCV-RNA testing, it was lower among females, individuals aged ≥60 years, and those without a history of blood transfusion, paid blood donation, or injection drug use. The willingness was higher among farmers or migrant workers, employees of enterprises or institutions, and those in other occupations (all P<0.05). Conclusions:There was room for improvement in the awareness proportion of HCV infection and willingness for HCV-RNA testing among hepatitis C cases in the four provinces of China. More convenient policies and measures should be provided to increase the awareness rate of HCV infection and the willingness to undergo HCV-RNA testing in this population.

Objective:To investigate the impact of immunosuppressive therapy on the severity of SARS-CoV-2 infection and cytokine levels in pediatric patients with kidney diseases.Methods:A retrospective analysis was conducted on the clinical data of 40 hospitalized pediatric patients who were diagnosed with SARS-CoV-2 infection at the 900th Hospital of PLA Joint Logistic Support Force from December 2022 to February 2023. Based on their immunosuppressive status prior to SARS-CoV-2 infection, these patients were categorized into immunosuppressive group and non-immunosuppressive group. Independent sample t-tests, Mann-Whitney U tests, and χ2 test were employed to compare the clinical baseline characteristics and laboratory data, the severity of SARS-CoV-2 infection, and the levels of cytokines between the 2 groups. Results:Among the 40 patients, 11 were in the immunosuppressive group (aged 13 (8, 14) years, 9 males and 2 females) and 29 in the non-immunosuppressive group (aged 2 (1, 4) years, 15 males and 14 females). In the immunosuppressive group, 2 were asymptomatic cases, 8 were mild cases, and 1 was moderate case, and there was no severe or critical cases. In the non-immunosuppressive group, 8 were mild cases, 5 were moderate, 15 were severe cases, 1 was critical case, and no asymptomatic cases. The underlying diseases in the immunosuppressive group included nephrotic syndrome (6 cases), IgA vasculitis nephritis (2 cases), lupus nephritis (1 case), post-renal transplantation (1 case), and renal failure (1 case), with a mean total immunosuppression score (TIS) of (3.6±1.4) points. In the non-immunosuppressive group, 2 patients had a history of epilepsy, and the remaining 27 cases had no underlying conditions, all with TIS scores of 0. Compared to the children in the non-immunosuppressive group, those in the immunosuppressive group were more likely to exhibit asymptomatic or mild infection, with lower risks of severe disease, cytokine storm, fever, and cough, but a higher risk of fatigue ( OR=1.22, 2.66, 0.48, 0.12, 0.12, 0.13, 1.22; 95% CI 0.93-1.62, 0.99-7.15, 0.33-0.70, 0.03-0.57, 0.03-0.57, 0.03-0.65, 0.93-1.62; all P<0.05). The levels of cytokine IL-6, interferon-α and interferon-γ in the immunosuppressive group were all lower than those in the non-immunosuppressive group ( Z=2.23, 2.51, 2.92, respectively; all P<0.05). Conclusion:Pediatric patients with kidney diseases receiving appropriate immunosuppressive therapy may mitigate the severity of SARS-CoV-2 infection by suppressing the expression of cytokines.

Objective:To determine the best scoring system for assessing the severity of perioperative aortic dissection.Methods:All data were obtained from the Medical Information Mart for Intensive Care-Ⅳ(MIMIC-Ⅳ) database in the United States. The predictive value of the Acute Physiology Score Ⅲ(APS Ⅲ), Oxford Acute Severity of Illness Score (OASIS), Sequential Organ Failure Assessment (SOFA), Simplified Acute Physiology Score Ⅱ(SAPS Ⅱ), and Charlson Comorbidity Index (CCI) scoring systems were evaluated using the receiver operating characteristic ( ROC) curve. The area under the curve ( AUC) was used to determine the best predictive score, and the ideal cutoff value of the score was calculated based on the Youden index. Patients were divided into high and low groups according to the cutoff value. The Kaplan- Meier curve was used to show the impact on the survival rate of patients with aortic dissection. Results:ROC curve analysis showed that APS Ⅲ( AUC: 0.803, 95% CI: 0.721-0.885) was superior to SAPS Ⅱ( AUC: 0.767, 95% CI: 0.654-0.880), OASIS( AUC: 0.760, 95% CI: 0.635-0.885), SOFA( AUC: 0.753, 95% CI: 0.649-0.857), and CCI( AUC: 0.670, 95% CI: 0.524-0.817) in assessing in-hospital mortality. Based on the ROC curve and the Youden index calculation, the ideal cutoff value of the APS Ⅲ score was 57.5. Kaplan- Meier survival analysis showed that patients in the high group of APS Ⅲ had a shorter 28-day survival time. Patients in the high group of APS Ⅲ had a higher incidence of postoperative complications, and correlation analysis showed that patients in the high group of APS Ⅲ had a longer hospital stay. Conclusion:The APS Ⅲ scoring system is more valuable in predicting the 28-day mortality and prognosis of patients with aortic dissection.