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.

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.

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 propose a novel mechanical method and index to in-vivo characterize the health status of cancellous bone during the percutaneous kyphoplasty(PKP),and validate its feasibility and consistency.Methods According to the theory of elasticity,the expression and physical significance of the mechanical index K were given.Then using clinical images of the lumbar spine L4,three-dimensional finite element simulations were conducted to verify the validity of the theoretical results,as well as the consistency of the methodology and the indexes were verified for studies of different balloon shapes and puncture routes.Results The internal pressure of the balloon linearly varied with the injected fluid volume.The mechanical index K was closely related to the bone shear modulus and could well reflect the health status of cancellous bones.The balloon shape had a trivial influence on the Kresults,and the relative difference between the cylindrical and ellipsoidal shapes was less than 2％.The influence of surgical access route on the K results was also very small,and the relative difference between the routes by vertebral pedicle and by lateral margin of vertebral pedicle was less than 0.5％.Conclusions The in-vivo mechanical method and the mechanical index K can characterize the bone health of patients with good consistency.This study has a great significance for providing guidelines of the optimization of PKP operation plan and postoperative rehabilitation,collecting in vivo data of bone mechanical properties,and improving the diagnosis and treatment of osteoporosis in clinic.

Objective To propose a novel mechanical method and index to in-vivo characterize the health status of cancellous bone during the percutaneous kyphoplasty(PKP),and validate its feasibility and consistency.Methods According to the theory of elasticity,the expression and physical significance of the mechanical index K were given.Then using clinical images of the lumbar spine L4,three-dimensional finite element simulations were conducted to verify the validity of the theoretical results,as well as the consistency of the methodology and the indexes were verified for studies of different balloon shapes and puncture routes.Results The internal pressure of the balloon linearly varied with the injected fluid volume.The mechanical index K was closely related to the bone shear modulus and could well reflect the health status of cancellous bones.The balloon shape had a trivial influence on the Kresults,and the relative difference between the cylindrical and ellipsoidal shapes was less than 2％.The influence of surgical access route on the K results was also very small,and the relative difference between the routes by vertebral pedicle and by lateral margin of vertebral pedicle was less than 0.5％.Conclusions The in-vivo mechanical method and the mechanical index K can characterize the bone health of patients with good consistency.This study has a great significance for providing guidelines of the optimization of PKP operation plan and postoperative rehabilitation,collecting in vivo data of bone mechanical properties,and improving the diagnosis and treatment of osteoporosis in clinic.

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.

Objective:To compare the mid-term clinical effects of AngioJet rheolytic thrombectomy assisted catheter-directed thrombolysis (ART+CDT) with catheter-directed thrombolysis (CDT) in the treatment of acute deep venous thrombosis of lower extremities.Methods:Ninety-one patients admitted to the Department from Jan 2016 to Dec 2017 were placed with inferior vena cava filters and divided into ART+CDT group (30 cases)and CDT group (61 cases). Total urokinase dosge, thrombolytic time, operative cost, length of hospital stay, detumescence rate, thrombus clearance rate, cumulative patency rate of lower limb veins, Villalta score at 2 years and 5 years, thrombosis recurrence rate and chronic venous insufficiency quality of life questionnaire were compared between the two groups.Results:The success rate of surgery was 100% in both groups, there was no mortality. There were significant differences in the short-term postoperative outcomes between the two groups in terms of total dosage of urokinase, thrombolysis time, total cost of surgery, length of hospital stay, detumescence rate, venous patency scores before and after treatment, and venous patency rate (all P<0.05). For the mid- and long-term postoperative outcomes of 2 and 5 years, there were no significant differences in the incidence of PTS, recurrence rate of thrombus, chronic venous function scale, and cumulative patency rate at 2 years (all P>0.05). Conclusions:ART+CDT has a significant advantage over CDT alone in terms of early efficacy and early reopening of blood flow in patients. Both ART+CDT and CDT have a low incidence of PTS and a low recurrence rate of thrombus in the mid-term follow-up, and both have satisfactory performance in the mid- and long-term efficacy of interventional treatment of deep venous thrombosis of lower limbs.

Objective To explore the changes of hepatic and pancreatic fat content in patients with type 2 diabetes mellitus(T2DM)using quantitative MRI,and to discuss the relationship with pancreatic β-cell function and bone mineral density(BMD).Methods A total of 118 patients with T2DM(T2DM group)were selected as the research subjects.At the same time,100 healthy control(HC)(HC group)who received physical examination were selected.All patients were examined with MRI.Hepatic fat fraction(HFF)and pancreatic fat fraction(PFF)were detected using the iterative decomposition of water and fat with echo asymmetry and least square estimation quantitation(IDEAL-1Q)technology.The homeostasis model assessment of β-cell function(HOMA-β)and homeostasis model assessment of insulin resistance(HOMA-IR)were performed.BMD of L2-L4,femoral neck and total hip were measured by dual-energy X-ray absorptiometry.The correlations among HFF,PFF and HOMA-β,HOMA-IR and BMD of L2-L4,femoral neck and total hip were analyzed by Pearson method.Results HFF and PFF in the T2DM group[(14.12±2.19)％and(8.23±1.60)％]were higher than those in the HC group[(5.30±0.83)％and(4.36±0.85)％],with statistically significant differences(P＜0.05).HOMA-βand BMD of L2-L4,femoral neck and total hip in the T2DM group[14.50±3.63,(0.92±0.13)mg/cm3,(0.77±0.10)mg/cm3 and(0.83±0.12)mg/cm3]were lower than those in the HC group[25.22±5.43,(1.05±0.23)mg/cm3,(0.85±0.18)mg/cm3 and(0.91±0.20)mg/cm3].HOMA-IR in the T2DM group(3.56±1.22)was higher than that in the HC group(1.90±0.45).The differences were statistically significant(P＜0.05).Pearson correlation analysis found that HFF and PFF were negatively correlated with HOMA-β and BMD of L2-L4,femoral neck and total hip,and were positively correlated with HOMA-IR(P＜0.05).Conclusion MRI can be used to quantitatively evaluate hepatic and pancreatic fat content in patients with T2DM.In addition,hepatic and pancreatic fat content are closely related to pancreatic HOMA-β,HOMA-IR and BMD.

Objective:To investigate the early clinical characteristics of elderly patients with severe burns and the risk factors on prognosis.Methods:This study was a retrospective case series study. Clinical data of 124 elderly patients with severe burns who met the inclusion criteria and were admitted to the 12 hospitals from January 2015 to December 2020 were collected, including 4 patients from the Fourth People's Hospital of Dalian, 5 patients from Fujian Medical University Union Hospital, 22 patients from Guangzhou Red Cross Hospital of Jinan University, 5 patients from Heilongjiang Provincial Hospital, 27 patients from the First Affiliated Hospital of Naval Medical University, 9 patients from the First Affiliated Hospital of Nanchang University, 10 patients from Affiliated Hospital of Nantong University, 9 patients from Tongren Hospital of Wuhan University & Wuhan Third Hospital, 12 patients from the 924 th Hospital of PLA, 6 patients from Zhangjiagang First People's Hospital, 4 patients from Taizhou Hospital of Zhejiang Province, and 11 patients from Zhengzhou First People's Hospital. The patients' overall clinical characteristics, such as gender, age, body mass index, total burn area, full-thickness burn area, inhalation injury, causative factors, whether combined with underlying medical diseases, and admission time after injury were recorded. According to the survival outcome within 28 days after injury, the patients were divided into survival group (89 cases) and death group (35 cases). The following data of patients were compared between the two groups, including the basic data and injuries (the same as the overall clinical characteristics ahead); the coagulation indexes within the first 24 hours of injury such as prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time, D-dimer, fibrinogen degradation product (FDP), international normalized ratio (INR), and fibrinogen; the blood routine indexes within the first 24 hours of injury such as white blood cell count, platelet count, neutrophil-to-lymphocyte ratio, monocyte count, red blood cell count, hemoglobin, and hematocrit; the organ function indexes within the first 24 hours of injury such as direct bilirubin, total bilirubin, urea, serum creatinine, aspartate aminotransferase, alanine aminotransferase, total protein, albumin, globulin, blood glucose, triglyceride, total cholesterol, alkaline phosphatase, creatine kinase, electrolyte indexes (potassium, sodium, chlorine, calcium, magnesium, and phosphorus in blood), uric acid, myoglobin, and brain natriuretic peptide; the infection and blood gas indexes within the first 24 hours of injury such as procalcitonin, C-reactive protein, pH value, oxygenation index, base excess, and lactate; treatment such as whether conducted with mechanical ventilation, whether conducted with continuous renal replacement therapy, whether conducted with anticoagulation therapy, whether applied with vasoactive drugs, and fluid resuscitation. The analysis was conducted to screen the independent risk factors for the mortality within 28 days after injury in elderly patients with severe burns. Results:Among 124 patients, there were 82 males and 42 females, aged 60-97 years, with body mass index of 23.44 (21.09, 25.95) kg/m 2, total burn area of 54.00% (42.00%, 75.00%) total body surface area (TBSA), and full-thickness burn area of 25.00% (10.00%, 40.00%) TBSA. The patients were mainly combined with moderate to severe inhalation injury and caused by flame burns. There were 43 cases with underlying medical diseases. The majority of patients were admitted to the hospital within 8 hours after injury. There were statistically significant differences between patients in the 2 groups in terms of age, total burn area, full-thickness burn area, and inhalation injury, and PT, APTT, D-dimer, FDP, INR, white blood cell count, platelet count, urea, serum creatinine, blood glucose, blood sodium, uric acid, myoglobin, and urine volume within the first 24 hours of injury (with Z values of 2.37, 5.49, 5.26, 5.97, 2.18, 1.95, 2.68, 2.68, 2.51, 2.82, 2.14, 3.40, 5.31, 3.41, 2.35, 3.81, 2.16, and -3.82, respectively, P<0.05); there were statistically significant differences between two groups of patients in whether conducted with mechanical ventilation and whether applied with vasoactive drugs (with χ2 values of 9.44 and 28.50, respectively, P<0.05). Age, total burn area, full-thickness burn area, serum creatinine within the first 24 hours of injury, and APTT within the first 24 hours of injury were the independent risk factors for the mortality within 28 days after injury in elderly patients with severe burns (with odds ratios of 1.17, 1.10, 1.10, 1.09, and 1.27, 95% confidence intervals of 1.03-1.40, 1.04-1.21, 1.05-1.19, 1.05-1.17, and 1.07-1.69, respectively, P<0.05). Conclusions:The elderly patients with severe burns had the injuries mainly from flame burns, often accompanied by moderate to severe inhalation injury and enhanced inflammatory response, elevated blood glucose levels, activated fibrinolysis, and impaired organ function in the early stage, which are associated with their prognosis. Age, total burn area, full-thickness burn area, and serum creatinine and APTT within the first 24 hours of injury are the independent risk factors for death within 28 days after injury in this population.