Objective To investigate the effect of Polyetheretherketone(PEEK)rod semi-rigid pedicle screw fixation sys-tem in lumbar spine non-fusion surgery.Methods A total of 74 patients with tow-level lumbar degenerative diseases who un-derwent surgery from March 2017 to December 2019 were divided into PEEK rod group and titanium rod group.In the PEEK rod group,there were 34 patients,including 13 males and 21 females,aged from 51 to 79 years old with an average of(62.4±6.8)years old;There were 1 patient of L1-L3 segments,7 patients of L2-L4 segments,20 patients of L3-L5 segments and 6 pa-tients of L4-S1 segments.In the titanium rod group,there were 40 patients,including 17 males and 23 females,aged from 52 to 81 years old with an average of(65.2±7.3)years old;There were 3 patient of L1-L3 segments,11 patients of L2-L4 segments,19 patients of L3-L5 segments and 7 patients of L4-S1 segments.The general conditions of operation,such as operation time,intraoperative blood loss,postoperative drainage was recorded.The visual analogue scale(VAS)for low back pain and Os-westry disability index(ODI)were compared in preoperatively and postoperatively(3 months,12 months and last follow-up)between two groups.The change of range of motion(ROM)was observed by flexion and extension x-ray of lumbar Results All patients successfully completed the operation.The follow-up time ranged from 22 to 34 months with an average of(26.8±5.6)months.The operative time(142.2±44.7)min and intraoperative blood loss(166.5±67.4)ml in PEEK group were lower than those in titanium group[(160.7±57.3)min、(212.8±85.4)ml](P＜0.05).There was no significant differences in postoperative drainage between the two groups(P＞0.05).At the final follow-up visit,in PEEK group and titanium group VAS of low back pain[(0.8±0.4)points vs(1.0±0.5)points],VAS for leg pain[(0.7±0.4)points vs(0.8±0.5)points]and ODI[(9.8±1.6)％vs(12.1±1.5)％]were compared with preoperative[(5.8±1.1)points vs(6.0±1.1)points],[(7.2±1.7)points vs(7.0±1.6)points],[(68.5±8.9)％vs(66.3±8.2)％]were significantly different(P＜0.05).There was no significant difference in VAS scores between the two groups at each postoperative time point(P＞0.05).At 3 months after surgery,there was no difference in ODI between the two groups(P＞0.05).There were significant differences in ODI between PEEK group and titanium rod group at 12 months[(15.5±2.1)％vs(18.4±2.4)％]and at the last follow-up[(9.8±1.6)％vs(12.1±1.5)％](P＜0.05).The total range of motion(ROM)of lumbar decreased in both groups after surgery.At 12 months after surgery and the last follow-up,the PEEK group compared with the titanium rod group,the total range of motion of lumbar was statistically significant(P＜0.05).The range of motion(ROM)of the fixed segments decreased in both groups after surgery.The ROM of the fixed segments in PEEK group decreased from(9.5±4.6)° to(4.1±1.9)° at the last follow-up(P＜0.05),which in the titanium rod group was de-creased from(9.8±4.3)°to(0.9±0.5)° at the last follow-up(P＜0.05).The range of motion(ROM)of upper adjacent segment increased in both groups,there was statistical significance in the ROM of upper adjacent segment between the two groups at 12 months after surgery and the last follow-up,(P＜0.05).There was no screw loosening and broken rods in both groups during the follow-up period.Conclusion The PEEK rod semi-rigid pedicle screw internal fixation system used in lumbar non-fusion surgery can retain part of the mobility of the fixed segment,showing comparable short-term clinical efficacy to titanium rod fu-sion.PEEK rod semi-rigid pedicle screw internal fixation system is a feasible choice for the treatment of lumbar spine degener-ative diseases,and its long-term efficacy needs further follow-up observation.

Sialic acid-binding immunoglobulin-like lectins(Siglecs)are expressed on most white blood cells and play a key role in signal transduction of immune cells.Recent studies have shown that many bacterial pathogens regulate the host immune response through the interaction between sialic acid(Sia)and Siglecs,thereby influencing the occurrence and development of diseases.Understanding bacterial pathogenic mechanisms is essential to identify potential effective therapeutic targets and help manage bacterial infectious diseases.Herein,the structure,biological function,and research progress in Siglecs in bacterial in-fectious diseases are briefly reviewed.

Objective:To establish a mesenchymal stem cell(MSC)-based in vitro cell model for the evaluation of mouse bone marrow acute graft-versus-host disease(aGVHD).Methods:Female C57BL/6N mice aged 6-8 weeks were used as bone marrow and lymphocyte donors,and female BALB/c mice aged 6-8 weeks were used as aGVHD recipients.The recipient mouse received a lethal dose(8.0 Gy,72.76 cGy/min)of total body γ irradiation,and injected with donor mouse derived bone marrow cells(1× 107/mouse)in 6-8 hours post irradiation to establish a bone marrow transplantation(BMT)mouse model(n=20).In addition,the recipient mice received a lethal dose(8.0 Gy,72.76 cGy/min)of total body γ irradiation,and injected with donor mouse derived bone marrow cells(1 × 107/mouse)and spleen lymphocytes(2 × 106/mouse)in 6-8 hours post irradiation to establish a mouse aGVHD model(n=20).On the day 7 after modeling,the recipient mice were anesthetized and the blood was harvested post eyeball enucleation.The serum was collected by centrifugation.Mouse MSCs were isolated and cultured with the addition of 2％,5％,and 10％recipient serum from BMT group or aGVHD group respectively.The colony-forming unit-fibroblast(CFU-F)experiment was performed to evaluate the potential effects of serums on the self-renewal ability of MSC.The expression of CD29 and CD105 of MSC was evaluated by immunofluorescence staining.In addition,the expression of self-renewal-related genes including Oct-4,Sox-2,and Nanog in MSC was detected by real-time fluorescence quantitative PCR(RT-qPCR).Results:We successfully established an in vitro cell model that could mimic the bone marrow microenvironment damage of the mouse with aGVHD.CFU-F assay showed that,on day 7 after the culture,compared with the BMT group,MSC colony formation ability of aGVHD serum concentrations groups of 2％and 5％was significantly reduced(P＜0.05);after the culture,at day 14,compared with the BMT group,MSC colony formation ability in different aGVHD serum concentration was significantly reduced(P＜0.05).The immunofluorescence staining showed that,compared with the BMT group,the proportion of MSC surface molecules CD29+and CD 105+cells was significantly dereased in the aGVHD serum concentration group(P＜0.05),the most significant difference was at a serum concentration of 10％(P＜0.001,P＜0.01).The results of RT-qPCR detection showed that the expression of the MSC self-renewal-related genes Oct-4,Sox-2,and Nanog was decreased,the most significant difference was observed at an aGVHD serum concentration of 10％(P＜0.01,P＜0.001,P＜0.001).Conclusion:By co-culturing different concentrations of mouse aGVHD serum and mouse MSC,we found that the addition of mouse aGVHD serum at different concentrations impaired the MSC self-renewal ability,which providing a new tool for the field of aGVHD bone marrow microenvironment damage.

Objectives:To assess the clinical characteristics and lead extraction in patients with venous occlusion related to infection of cardiovascular implantable electronic devices. Methods:Clinical data of 405 patients(147 men,mean age[62.4±13.2]years)who underwent lead extraction from January 2020 to January 2024 in Peking University People's Hospital were reviewed.Contrast venography of the access vein was retrospectively analyzed.The patients were divided into venous occlusion group(n=119)and non-venous occlusion group(n=286)according to the presence or absence of venous occlusion.The clinical characteristics and lead extraction of patients in two groups were analyzed. Results:Occlusion of the access vein occurred in 119 patients(29.4%).The subclavian vein was occluded in 48 cases(40.3%),brachiocephalic vein was occluded in 37 cases(31.1%),axillary vein was occluded in 30 cases(25.2%),superior vena cava was occluded in 4 cases(3.4%).There were no significant differences between venous occlusion group and non-venous occlusion group in terms of age,sex,device type,number of leads,or anticoagulation therapy(all P>0.05).Time from implant of the initial leads was significantly longer in the venous occlusion group than in the non-venous occlusion group([10.4±3.8]years vs.[5.9±4.1]years,P=0.042).Clinical extraction success rate and complications were similar between the venous occlusion group and the non-venous occlusion group(both P>0.05).Procedural duration and fluoroscopy exposure time were significantly lower in non-venous occlusion group than in the venous occlusion group(both P<0.05).Patients in the venous occlusion group required more advanced tools(such as laser sheaths,evolution sheaths,and needle's eye snares)for lead extraction compared to patients in the non-venous occlusion group(84.0%vs.67.1%,P=0.001). Conclusions:The incidence of venous occlusion related to infection of cardiovascular implantable electronic devices is 29.4%.Time from implant of the initial leads is significantly longer and lead extraction is more difficult in patients with venous occlusion,and requires more advanced tools and more time to achieve the successful lead extraction.

Objective To investigate the risk factors for bronchopulmonary dysplasia(BPD)in twin preterm infants with a gestational age of<34 weeks,and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.Methods A retrospective analysis was performed for the twin preterm infants with a gestational age of<34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020.According to their conditions,they were divided into group A(both twins had BPD),group B(only one twin had BPD),and group C(neither twin had BPD).The risk factors for BPD in twin preterm infants were analyzed.Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.Results A total of 904 pairs of twins with a gestational age of<34 weeks were included in this study.The multivariate logistic regression analysis showed that compared with group C,birth weight discordance of>25%between the twins was an independent risk factor for BPD in one of the twins(OR=3.370,95%CI:1.500-7.568,P<0.05),and high gestational age at birth was a protective factor against BPD(P<0.05).The conditional logistic regression analysis of group B showed that small-for-gestational-age(SGA)birth was an independent risk factor for BPD in individual twins(OR=5.017,95%CI:1.040-24.190,P<0.05).Conclusions The development of BPD in twin preterm infants is associated with gestational age,birth weight discordance between the twins,and SGA birth.

Objective To compare the clinical characteristics of diabetes mellitus(DM)patients complicated with pyogenic liver abscess(PLA)and non-DM(NDM)patients complicated with PLA,and provide evidence for clinical diagnosis and treatment.Methods PLA patients who admitted to an affiliated hospital of Anhui Medical University from July 2002 to February 2022 were selected and divided into DM+PLA group and NDM+PLA group according to whether they had DM.General condition,clinical manifestations and signs.complications,biochemical and patho-genic examination results,imaging findings,as well as clinical efficacy and influencing factors of the two groups of patients were analyzed retrospectively.Results 695 PLA patients were included in the analysis,191(27.5％)in the DM+PLA group and 504(72.5％)in the NDM+PLA group.The proportions of males and complication of hypertension in the DM+PLA group were higher than those in the NDM+PLA group,while the proportion of bi-liary diseases and malignant tumors was lower(all P＜0.05).The proportions of patients developing fever,fa-tigue,as well as concurrent anemia and hypoalbuminemia in the DM+PLA group were higher than those in the NDM+PLA group(all P＜0.05).Compared with the NDM+PLA group,the neutrophil count and percentage in the DM+PLA group increased,while total protein,albumin content,and albumin/globulin ratio all decreased(all P＜0.05).The proportions of the detection of Klebsiella pneumoniae and the occurrence of liver right lobe abscess in DM+PLA patients were higher than those of the NDM+PLA group(both P＜0.05).Multivariate logistic re-gression analysis revealed that malignant tumor was a risk factor for affecting the clinical efficacy of PLA patients,invasive treatment was a protect factor for affecting the clinical efficacy of PLA patients,while blood sugar was a risk factor for affecting the clinical efficacy of NDM+PLA patients.Conclusion DM+PLA patients have more se-vere infection symptoms than NDM+PLA patients,and are accompanied by higher proportions of Klebsiella pneu-moniae infection and liver right lobe abscess.It is necessary to strengthen attention to patients with malignant tumor and control blood sugar level,and timely supplement with invasive treatment if necessary.

Objective:To study the dosimetry effects of differently selected values of control point(CP)in Monaco radiotherapy planning system on dynamic intensity modulated radiation therapy(dIMRT)for esophageal cancer of middle and lower segment.Methods:Thirteen patients with esophageal cancer at middle and lower segment who received dIMRT in Shangluo Central Hospital from January to June 2023 were selected.In the Monaco radiotherapy planning system,nine groups of dIMRT plans were designed for each patient according to the 9 kinds of CP limit values(10,20,30,40,50,60,70,80 and 90).There were not changes in other optimized parameters except CP parameter.The differences of the dosimetry between target region and organs at risk(OAR)included lung,heart and spinal cord were analyzed.Results:With the increase of the CP limit value,the maximum dose of the target region which was radiation dose(D2%)of 2%volume of target region,the mean dose,which was radiation dose(D50%)of 50%volume of target region,and the homogeneity index(HI)appeared a trend of gradual stability after reduction,and the radiation dose(D98%)of 98%volume of target region which was the minimum dose of target region and the conformance index(CI)appeared a trend of gradual stability after increase.There was not significant in each dose indicator of OAR(P>0.05).The variation ranges of lung at 5,10,20,30 Gy dose(V5,V10,V20 and V30)were respectively 1.13%,0.75%,0.29%and 0.19%,and the maximum deviation of mean dose(Vmean)of lung was 18.7 cGy.The variation ranges of V10,V20,V30 and V40 in the heart were respectively 2.2%,1.23%,1.39%and 1.12%,and the maximum deviation of Vmean in the heart was 63.85 cGy,and the maximum deviation of Dmax in the spinal-cord was 70.78 cGy.There were statistically significant differences in the actual CP number(CPs),execution time(DT)of plan,and ratio value of machine unit(MU)of the complexity of plan to CPs(MU/CPs)among the plans of 9 groups(F=2.857,25.145,135.467,P<0.05),respectively.Conclusion:In the dIMRT plan of esophageal cancer of middle and lower segment,the maximum CP value is set at between 40-50,which can reduce the optimization time of the plan,the number of subfields and the treatment time of patients under the premise of meeting the dose of the target region and the OAR.

Hip fracture in the elderly is characterized by high incidence, high disability rate, and high mortality and has been recognized as a public health issue threatening their health. Surgery is the preferred choice for the treatment of elderly patients with hip fracture. However, lower extremity deep venous thrombosis (DVT) has an extremely high incidence rate during the perioperative period, and may significantly increase the risk of patients′ death once it progresses to pulmonary embolism. In response to this issue, the clinical guidelines and expert consensuses all emphasize active application of comprehensive preventive measures, including basic prevention, physical prevention, and pharmacological prevention. In this prevention system, basic prevention is the basis of physical and pharmacological prevention. However,there is a lack of unified and definite recommendations for basic preventive measures in clinical practice. To this end, the Orthopedic Nursing Professional Committee of the Chinese Nursing Association and Nursing Department of the Orthopedic Branch of the China International Exchange and Promotive Association for Medical and Health Care organized relevant nursing experts to formulate Expert consensus on perioperative basic prevention for lower extremity deep venous thrombosis in elderly patients with hip fracture ( version 2024) . A total of 10 recommendations were proposed, aiming to standardize the basic preventive measures for lower extremity DVT in elderly patients with hip fractures during the perioperative period and promote their subsequent rehabilitation.

Coronary restenosis is an important cause of poor long-term prognosis in patients with coronary heart disease. Here, we show that lysine methyltransferase SMYD2 expression in the nucleus is significantly elevated in serum- and PDGF-BB-induced vascular smooth muscle cells (VSMCs), and in tissues of carotid artery injury-induced neointimal hyperplasia. Smyd2 overexpression in VSMCs (Smyd2-vTg) facilitates, but treatment with its specific inhibitor LLY-507 or SMYD2 knockdown significantly inhibits VSMC phenotypic switching and carotid artery injury-induced neointima formation in mice. Transcriptome sequencing revealed that SMYD2 knockdown represses the expression of serum response factor (SRF) target genes and that SRF overexpression largely reverses the inhibitory effect of SMYD2 knockdown on VSMC proliferation. HDAC3 directly interacts with and deacetylates SRF, which enhances SRF transcriptional activity in VSMCs. Moreover, SMYD2 promotes HDAC3 expression via tri-methylation of H3K36 at its promoter. RGFP966, a specific inhibitor of HDAC3, not only counteracts the pro-proliferation effect of SMYD2 overexpression on VSMCs, but also inhibits carotid artery injury-induced neointima formation in mice. HDAC3 partially abolishes the inhibitory effect of SMYD2 knockdown on VSMC proliferation in a deacetylase activity-dependent manner. Our results reveal that the SMYD2-HDAC3-SRF axis constitutes a novel and critical epigenetic mechanism that regulates VSMC phenotypic switching and neointimal hyperplasia.

BACKGROUND:Bone mineral density is the clinical gold standard for determining bone strength,but bone mineral density is less sensitive to changes in bone mass,with large changes in bone mineral density only occurring when bone mass is significantly reduced,so bone mineral density has limited ability to predict changes in bone strength and fracture risk. OBJECTIVE:A model of the normal and osteoporotic hip joint was developed to analyze the stresses and deformation in the hip of normal and osteoporotic patients under single-leg standing conditions. METHODS:A healthy adult female volunteer at the age of 36 years was selected as the study subject.The CT data of the hip joint of this volunteer were obtained and saved in DICOM format.The hip joint model was reconstructed in three dimensions,and the material properties were assigned by the gray value assignment method to obtain the normal and osteoporotic hip joint models according to the empirical formula.The same boundary conditions and loads were set to simulate the stresses and deformation in the normal and osteoporotic hip joints in the single-leg standing position. RESULTS AND CONCLUSION:(1)In the finite element model of the normal and osteoporotic hip,the stress distribution was more concentrated in the medial region of the femoral neck.(2)In the hip bone,the stress distribution was mainly concentrated in the upper part of the acetabulum.(3)The stress peaks in the medial femoral neck and upper acetabulum were larger in the normal hip model than in the osteoporotic hip model,probably due to the reduced bone strength of the osteoporotic bone.(4)The peak Von Mises of both normal and osteoporotic hip models were concentrated on the medial femoral neck,and the peak Von Mises of the hip bone was smaller,indicating that the overall effect of osteoporosis on hip bone stresses was relatively small.(5)In terms of deformation in the single-leg standing position,the maximum deformation in the normal hip model was located at the acetabulum and femoral head,and the maximum deformation was located at the upper part of the greater trochanter of the femur.(6)It is suggested that the finite element analysis method to model the values of parameters related to bone tissue in osteoporosis may improve clinical prediction of bone strength changes and fracture risk.It is explained from the biomechanical view that the intertrochanteric femur and femoral neck are good sites for osteoporotic hip fractures.