BACKGROUND:Intertrochanteric fracture of femur has various fracture types and fixation methods,and the mechanical stability of each fixation system is quite different.It is of scientific clinical significance to use finite element analysis method to carry out biomechanical research on various fixation systems. OBJECTIVE:To compare and analyze the mechanical stability of various internal fixations applied to femoral intertrochanteric fracture A031-A2.1 by finite element method. METHODS:Based on the validated finite element model of femur(Intact),the model was cut and made into A031-A2.1 intertrochanteric fracture of femur.Different internal fixation systems were implanted by simulating clinical operation methods,and fixation models of proximal femoral nail antirotation,dynamic hip screw,percutaneous compression plate and proximal femoral locking plate were established respectively.All nodes under the distal femur of the four groups of models were constrained,and compression loads of 700,1 400 and 2 100 N were applied to the femoral head.Von Mises stress distribution and compression stiffness of each group of models were observed through calculation and analysis,and mechanical stability of each group was compared. RESULTS AND CONCLUSION:(1)Through calculation and analysis,after calculating the compression stiffness by comparing the deformation of each model,the compression stiffness of each model under various loads showed the trend:physiological group>proximal femoral nail antirotation group>proximal femoral locking plate group>percutaneous compression plate group>dynamic hip screw group.The compressive stiffness of the complete physiological group model was significantly higher than that of all surgical group models.(2)The stress index was observed.Due to the stress shielding effect,the stress peak value of each fixed group was higher than that of physiological group,and the maximum peak value was concentrated on each internal fixation.Proximal femoral nail antirotation group had the smallest stress peak,while dynamic hip screw group had the highest stress.The stress distribution trend showed physiological group

Objective To summarize the epidemiological and clinical features of infectious diseases of the central nervous system(CNS)by a single-center analysis.Methods A retrospective analysis was conducted on the data of 1247 cases of CNS infectious diseases diagnosed and treated in the First Medical Center of PLA General Hospital from 2001 to 2020.Results The data for this group of CNS infectious diseases by disease type in descending order of number of cases were viruses 743(59.6％),Mycobacterium tuberculosis 249(20.0％),other bacteria 150(12.0％),fungi 68(5.5％),parasites 18(1.4％),Treponema pallidum 18(1.4％)and rickettsia 1(0.1％).The number of cases increased by 177 cases(33.1％)in the latter 10 years compared to the previous 10 years(P<0.05).No significant difference in seasonal distribution pattern of data between disease types(P>0.05).Male to female ratio is 1.87︰1,mostly under 60 years of age.Viruses are more likely to infect students,most often at university/college level and above,farmers are overrepresented among bacteria and Mycobacterium tuberculosis,and more infections of Treponema pallidum in workers.CNS infectious diseases are characterized by fever,headache and signs of meningeal irritation,with the adductor nerve being the more commonly involved cranial nerve.Matagenomic next-generation sequencing improves clinical diagnostic capabilities.The median hospital days for CNS infectious diseases are 18.00(11.00,27.00)and median hospital costs are ￥29,500(￥16,000,￥59,200).The mortality rate from CNS infectious diseases is 1.6％.Conclusions The incidence of CNS infectious diseases is increasing last ten years,with complex clinical presentation,severe symptoms and poor prognosis.Early and accurate diagnosis and standardized clinical treatment can significantly reduce the morbidity and mortality rate and ease the burden of disease.

Objective:To assess the association between body mass index (BMI) and major adverse cardiovascular and cerebrovascular events (MACCE) among patients with acute coronary syndrome (ACS).Methods:This was a multicenter prospective cohort study, which was based on the Improving Care for Cardiovascular Disease in China (CCC) project. The hospitalized patients with ACS aged between 18 and 80 years, registered in CCC project from November 1, 2014 to December 31, 2019 were included. The included patients were categorized into four groups based on their BMI at the time of admission: underweight (BMI<18.5 kg/m 2), normal weight (BMI between 18.5 and 24.9 kg/m 2), overweight (BMI between 25.0 and 29.9 kg/m 2), and obese (BMI≥30.0 kg/m 2). Multivariate logistic regression models was used to analyze the relationship between BMI and the risk of in-hospital MACCE. Results:A total of 71 681 ACS inpatients were included in the study. The age was (63.4±14.7) years, and 26.5% (18 979/71 681) were female. And the incidence of MACCE for the underweight, normal weight, overweight, and obese groups were 14.9% (322/2 154), 9.5% (3 997/41 960), 7.9% (1 908/24 140) and 7.0% (240/3 427), respectively ( P<0.001). Multivariate logistic regression analysis showed a higher incidence of MACCE in the underweight group compared to the normal weight group ( OR=1.30, 95% CI 1.13-1.49, P<0.001), while the overweight and obese groups exhibited no statistically significant difference in the incidence of MACCE compared to the normal weight group (both P>0.05). Conclusion:ACS patients with BMI below normal have a higher risk of in-hospital MACCE, suggesting that BMI may be an indicator for evaluating short-term prognosis in ACS patients.

Objective To investigate the application value of combining the Demirjian's method with ma-chine learning algorithms for dental age estimation in northern Chinese Han children and adolescents.Methods Oral panoramic images of 10 256 Han individuals aged 5 to 24 years in northern China were collected.The development of eight permanent teeth in the left mandibular was classified into different stages using the Demirjian's method.Various machine learning algorithms,including support vector re-gression(SVR),gradient boosting regression(GBR),linear regression(LR),random forest regression(RFR),and decision tree regression(DTR)were employed.Age estimation models were constructed based on total,female,and male samples respectively using these algorithms.The fitting performance of different machine learning algorithms in these three groups was evaluated.Results SVR demonstrated superior estimation efficiency among all machine learning models in both total and female samples,while GBR showed the best performance in male samples.The mean absolute error(MAE)of the op-timal age estimation model was 1.246 3,1.281 8 and 1.153 8 years in the total,female and male samples,respectively.The optimal age estimation model exhibited varying levels of accuracy across dif-ferent age ranges,which provided relatively accurate age estimations in individuals under 18 years old.Conclusion The machine learning model developed in this study exhibits good age estimation effi-ciency in northern Chinese Han children and adolescents.However,its performance is not ideal when applied to adult population.To improve the accuracy in age estimation,the other variables can be con-sidered.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective:To prepare mesenchymal stem cells with antioxidant capacity (AO-MSC ) from human umbilical cords and evaluate its cell biological properties.Methods:In control group,mesenchymal stem cells (MSC) were isolated by digesting human umbilical cord Wharton's Jelly tissues with 0.2％ collagenase Ⅱ,and the released cells were collected and cultured in an animal serum-free culture medium.In AO-MSC group,incompletely collagenase Ⅱ-digested tissue debris were allowed to adhere to flusk flat bottoms and the AO-MSC was harvested by adherent culture. The conventional digestion and culture method was used as control.MSC colony forming ability was evaluated by fibroblast colony forming assay (CFU-F).MSC proliferative capacity was evaluated by CCK-8 assay.The MSC surface markers were detected by using flow cytometry and immunofluorescence staining.The adipogenic and osteogenic capacity of MSC was evaluated by multi-differentiation in vitro,and the mRNA expression of genes that control adipogenic and osteogenic differentiation was detected by real-time fluorescence quantitative PCR (RT-qPCR );Moreover,the mRNA expression of antioxidant substances such as SOD-1,GSH,GAT,and NQO1 in MSC was also evaluated by RT-qPCR.Results:The AO-MSC isolated by this strategy reached a confluence of 80％-90％ at around 18 days and grew in a swirling pattern.Flow cytometry and immunofluorescence staining assays showed that CD73,CD29,CD105,CD90 were highly expressed and CD31,CD45,HLA-DR were scarcely expressed in AO-MSC.AO-MSC exhibited stronger self-renewal and differentiation ability compared to MSC.However,the in vitro adipogenic-osteogenic capacity of MSC in the control group was stronger than that of AO-MSC.RT-qPCR assay showed that AO-MSC expressed higher mRNA levels of antioxidant substances compared to MSC.Conclusion:Human AO-MSC is successfully prepared from human umbilical cord without animal serum.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Ultra-performance liquid chromatography-quadrupole time of fight/mass spectrometry(UPLC-Q-TOF-MS) and UNIFI were employed to rapidly determine the content of the components in Liangxue Tuizi Mixture. The targets of the active components and Henoch-Schönlein purpura(HSP) were obtained from SwissTargetPrediction, Online Mendelian Inheritance in Man(OMIM), and GeneCards. A "component-target-disease" network and a protein-protein interaction(PPI) network were constructed. Gene Ontology(GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis were performed for the targets by Omishare. The interactions between the potential active components and the core targets were verified by molecular docking. Furthermore, rats were randomly assigned into a normal group, a model group, and low-, medium-, and high-dose Liangxue Tuizi Mixture groups. Non-targeted metabolomics was employed to screen the differential metabolites in the serum, analyze possible metabolic pathways, and construct the "component-target-differential metabolite" network. A total of 45 components of Liangxue Tuizi Mixture were identified, and 145 potential targets for the treatment of HSP were predicted. The main signaling pathways enriched included resistance to epidermal growth factor receptor tyrosine kinase inhibitors, phosphatidylinositol 3-kinase/protein kinase B(PI3K-AKT), and T cell receptor. The results of molecular docking showed that the active components in Liangxue Tuizi Mixture had strong binding ability with the key target proteins. A total of 13 differential metabolites in the serum were screened out, which shared 27 common targets with active components. The progression of HSP was related to metabolic abnormalities of glycerophospholipid and sphingolipid. The results indicate that the components in Liangxue Tuizi Mixture mainly treats HSP by regulating inflammation and immunity, providing a scientific basis for rational drug use in clinical practice.
Animals ; Rats ; IgA Vasculitis/drug therapy* ; Network Pharmacology ; Molecular Docking Simulation ; Phosphatidylinositol 3-Kinases ; Metabolomics

Background In mainland China, patients with neovascular age-related macular degeneration (nAMD) have approximately an 40% prevalence of polypoidal choroidal vasculopathy (PCV). This disease leads to recurrent retinal pigment epithelium detachment (PED), extensive subretinal or vitreous hemorrhages, and severe vision loss. China has introduced various treatment modalities in the past years and gained comprehensive experience in treating PCV.Methods A total of 14 retinal specialists nationwide with expertise in PCV were empaneled to prioritize six questions and address their corresponding outcomes, regarding opinions on inactive PCV, choices of anti-vascular endothelial growth factor (anti-VEGF) monotherapy, photodynamic therapy (PDT) monotherapy or combined therapy, patients with persistent subretinal fluid (SRF) or intraretinal fluid (IRF) after loading dose anti-VEGF, and patients with massive subretinal hemorrhage. An evidence synthesis team conducted systematic reviews, which informed the recommendations that address these questions. This guideline used the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach to assess the certainty of evidence and grade the strengths of recommendations. Results The panel proposed the following six conditional recommendations regarding treatment choices. (1) For patients with inactive PCV, we suggest observation over treatment. (2) For treatment-na?ve PCV patients, we suggest either anti-VEGF monotherapy or combined anti-VEGF and PDT rather than PDT monotherapy. (3) For patients with PCV who plan to initiate combined anti-VEGF and PDT treatment, we suggest later/rescue PDT over initiate PDT. (4) For PCV patients who plan to initiate anti-VEGF monotherapy, we suggest the treat and extend (T&E) regimen rather than the pro re nata (PRN) regimen following three monthly loading doses. (5) For patients with persistent SRF or IRF on optical coherence tomography (OCT) after three monthly anti-VEGF treatments, we suggest proceeding with anti-VEGF treatment rather than observation. (6) For PCV patients with massive subretinal hemorrhage (equal to or more than four optic disc areas) involving the central macula, we suggest surgery (vitrectomy in combination with tissue-plasminogen activator (tPA) intraocular injection and gas tamponade) rather than anti-VEGF monotherapy. Conclusions Six evidence-based recommendations support optimal care for PCV patients' management.

Humans ; Induction Chemotherapy ; Benzamides ; Treatment Outcome ; Hematopoietic Stem Cell Transplantation ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy* ; Remission Induction ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use*