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

Objectives: This study evaluates the efficacy of a new temporomandibular joint (TMJ) capsule suspension technique for stabilizing the TMJ after free fibular flap reconstruction of the mandibular condyle. Patients and Methods: Patients undergoing the TMJ capsule suspension technique during free fibular flap reconstruction after mandibulectomy with condylectomy (study group; n=9) were compared with a control group (n=9). Mandibular movement trajectory and surface electromyographic signals of bilateral masseters were recorded. The neocondyle–disc relationship was examined with magnetic resonance imaging (MRI) at 6 months after surgery. Results: Maximal mouth opening and bilateral marginal movement distances were comparable between the two groups (P>0.05). The asymmetry index of the condyle path length was significantly higher in controls (P=0.02). Bilateral mouth opening trajectories were symmetric in 7 patients and deviated to the affected side in 2 patients in the study group; they deviated to the affected side in all controls. The mean electromyographic values of the masseter on the affected side in resting, maximum bite, and chewing states were comparable between the two groups (P=0.13, P=0.65, and P=0.82, respectively). On MRI at 6 months, the thicknesses of the anterior, medial, and posterior bands and TMJ disc length were similar on the affected and normal sides in the study group (P=0.57, P=0.13, P=0.48, and P=0.87, respectively). Conclusion The proposed TMJ capsule suspension technique could improve postoperative TMJ structure and function after fibular free flap reconstruction following mandibulectomy with condylectomy.

Objectives: This study evaluates the efficacy of a new temporomandibular joint (TMJ) capsule suspension technique for stabilizing the TMJ after free fibular flap reconstruction of the mandibular condyle. Patients and Methods: Patients undergoing the TMJ capsule suspension technique during free fibular flap reconstruction after mandibulectomy with condylectomy (study group; n=9) were compared with a control group (n=9). Mandibular movement trajectory and surface electromyographic signals of bilateral masseters were recorded. The neocondyle–disc relationship was examined with magnetic resonance imaging (MRI) at 6 months after surgery. Results: Maximal mouth opening and bilateral marginal movement distances were comparable between the two groups (P>0.05). The asymmetry index of the condyle path length was significantly higher in controls (P=0.02). Bilateral mouth opening trajectories were symmetric in 7 patients and deviated to the affected side in 2 patients in the study group; they deviated to the affected side in all controls. The mean electromyographic values of the masseter on the affected side in resting, maximum bite, and chewing states were comparable between the two groups (P=0.13, P=0.65, and P=0.82, respectively). On MRI at 6 months, the thicknesses of the anterior, medial, and posterior bands and TMJ disc length were similar on the affected and normal sides in the study group (P=0.57, P=0.13, P=0.48, and P=0.87, respectively). Conclusion The proposed TMJ capsule suspension technique could improve postoperative TMJ structure and function after fibular free flap reconstruction following mandibulectomy with condylectomy.

Objectives: This study evaluates the efficacy of a new temporomandibular joint (TMJ) capsule suspension technique for stabilizing the TMJ after free fibular flap reconstruction of the mandibular condyle. Patients and Methods: Patients undergoing the TMJ capsule suspension technique during free fibular flap reconstruction after mandibulectomy with condylectomy (study group; n=9) were compared with a control group (n=9). Mandibular movement trajectory and surface electromyographic signals of bilateral masseters were recorded. The neocondyle–disc relationship was examined with magnetic resonance imaging (MRI) at 6 months after surgery. Results: Maximal mouth opening and bilateral marginal movement distances were comparable between the two groups (P>0.05). The asymmetry index of the condyle path length was significantly higher in controls (P=0.02). Bilateral mouth opening trajectories were symmetric in 7 patients and deviated to the affected side in 2 patients in the study group; they deviated to the affected side in all controls. The mean electromyographic values of the masseter on the affected side in resting, maximum bite, and chewing states were comparable between the two groups (P=0.13, P=0.65, and P=0.82, respectively). On MRI at 6 months, the thicknesses of the anterior, medial, and posterior bands and TMJ disc length were similar on the affected and normal sides in the study group (P=0.57, P=0.13, P=0.48, and P=0.87, respectively). Conclusion The proposed TMJ capsule suspension technique could improve postoperative TMJ structure and function after fibular free flap reconstruction following mandibulectomy with condylectomy.

ObjectiveJunctophilin-2 (JPH2) is an essential structural protein that maintains junctional membrane complexes (JMCs) in cardiomyocytes by tethering the plasma membrane to the sarcoplasmic reticulum, thereby facilitating excitation-contraction (E-C) coupling. Mutations in JPH2 have been associated with hypertrophic cardiomyopathy (HCM), but the molecular mechanisms governing its membrane-binding properties and the functional relevance of its membrane occupation and recognition nexus (MORN) repeat motifs remain incompletely understood. This study aimed to elucidate the structural basis of JPH2 membrane association and its implications for HCM pathogenesis. MethodsA recombinant N-terminal fragment of mouse JPH2 (residues1-440), encompassing the MORN repeats and an adjacent helical region, was purified under near-physiological buffer conditions.X-ray crystallography was employed to determine the structure of the JPH2 MORN-Helix domain. Sequence conservation analysis across species and junctophilin isoforms was performed to assess the evolutionary conservation of key structural features. Functional membrane-binding assays were conducted using liposome co-sedimentation and cell-based localization studies in COS7 and HeLa cells. In addition, site-directed mutagenesis targeting positively charged residues and known HCM-associated mutations, including R347C, was used to evaluate their effects on membrane interaction and subcellular localization. ResultsThe crystal structure of the mouse JPH2 MORN-Helix domain was resolved at 2.6 Å, revealing a compact, elongated architecture consisting of multiple tandem MORN motifs arranged in a curved configuration, forming a continuous hydrophobic core stabilized by alternating aromatic residues. A C-terminal α-helix further reinforced structural integrity. Conservation analysis identified the inner groove of the MORN array as a highly conserved surface, suggesting its role as a protein-binding interface. A flexible linker segment enriched in positively charged residues, located adjacent to the MORN motifs, was found to mediate direct electrostatic interactions with negatively charged phospholipid membranes. Functional assays demonstrated that mutation of these basic residues impaired membrane association, while the HCM-linked R347C mutation completely abolished membrane localization in cellular assays, despite preserving the overall MORN-Helix fold in structural modeling. ConclusionThis study provides structural insight into the membrane-binding mechanism of the cardiomyocyte-specific protein JPH2, highlighting the dual roles of its MORN-Helix domain in membrane anchoring and protein interactions. The findings clarify the structural basis for membrane targeting via a positively charged linker and demonstrate that disruption of this interaction—such as that caused by the R347C mutation—likely contributes to HCM pathogenesis. These results not only enhance current understanding of JPH2 function in cardiac E-C coupling but also offer a structural framework for future investigations into the assembly and regulation of JMCs in both physiological and disease contexts.

Child ; Humans ; Mpox (monkeypox)/prevention & control* ; Disease Outbreaks

Aim To investigate the regulatory effect of Cortaetin on pathological myocardial hypertrophy induced by isoprenaline (ISO) and the underlying mechanism. Methods ISO was used to stimulate neonatal rat cardiomyocytes for 24 h, and myocardial hypertrophy model was established at the cellular level. C57BL/6 mice were injected subcutaneously with ISO for one week to establish myocardial hypertrophy model at animal level. RT-qPCR was used to detect the changes of mRNA and Western blot was used to detect the changes of relative protein content. Immunofluorescence was used to measure the subcellular location of Cortaetin and the change of its expression. The overex-pression of Cortaetin by adenovirus infection and the knockdown of Cortaetin by transfection of small interfering RNA were studied. Results On the cellular and animal levels, ISO-induced myocardial hypertrophy models were successfully established, and it was observed that ISO caused the decrease of Cortaetin and N-cadherin protein levels. Overexpression of Cortaetin could reverse the decrease of N-cadherin protein level and myocardial hypertrophy caused by ISO. Knockdown of Cortaetin showed the opposite effect. Conclusion Cortaetin, in combination with N-cadherin, may play a role in combating myocardial hypertrophy by enhancing the connections between cardiomyocytes.

The coronavirus disease 2019 (COVID-19) is an acute infectious disease caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which has led to serious worldwide economic burden. Due to the continuous emergence of variants, vaccines and monoclonal antibodies are only partial effective against infections caused by distinct strains of SARS-CoV-2. Therefore, it is still of great importance to call for the development of broad-spectrum and effective small molecule drugs to combat both current and future outbreaks triggered by SARS-CoV-2. Cathepsin L (CatL) cleaves the spike glycoprotein (S) of SARS-CoV-2, playing an indispensable role in enhancing virus entry into host cells. Therefore CatL is one of the ideal targets for the development of pan-coronavirus inhibitor-based drugs. In this study, a CatL enzyme inhibitor screening model was established based on fluorescein labeled substrate. Two CatL inhibitors IMB 6290 and IMB 8014 with low cytotoxicity were obtained through high-throughput screening, the half inhibition concentrations (IC₅₀) of which were 11.53 ± 0.68 and 1.56 ± 1.10 μmol·L^-1, respectively. SDS-PAGE and cell-cell fusion experiments confirmed that the compounds inhibited the hydrolysis of S protein by CatL in a concentration-dependent manner. Surface plasmon resonance (SPR) detection showed that both compounds exhibited moderate binding affinity with CatL. Molecular docking revealed the binding mode between the compound and the CatL active pocket. The pseudovirus experiment further confirmed the inhibitory effects of IMB 8014 on the S protein mediated entry process. In vitro pharmacokinetic evaluation indicated that the compounds had relatively good drug-likeness properties. Our research suggested that these two compounds have the potential to be further developed as antiviral drugs for COVID-19 treatment.

Objective To investigate the efficacy of Dingxuan Decoction combined with vestibular function rehabilitation training in the treatment of Meniere's disease and to observe its effect on clinical symptoms and blood flow of vertebral artery.Methods A total of 100 patients with Meniere's disease of liver-kidney yin deficiency complicated with wind-water upward stirring type were randomly divided into an observation group and a control group,with 50 patients in each group.The control group was given conventional treatment and vestibular function rehabilitation training,and the observation group was treated with Dingxuan Decoction on the basis of treatment for the control group.The two groups were treated for 4 weeks and then were followed up for 6 months.The changes of traditional Chinese medicine(TCM)syndrome score,Dizziness Handicap Inventory(DHI)score,Tinnitus Handicap Inventory(THI)score,hearing visual analogue scale(VAS)score and vertebral artery blood flow in the two groups were observed before and after the treatment.After treatment,the TCM syndrome efficacy,hearing improvement and follow-up results were compared between the two groups.Results(1)After 4 weeks of treatment,the total effective rate for TCM syndrome efficacy of the observation group was 86.00%(43/50),and that of the control group was 62.00%(31/50),and the intergroup comparison showed that the TCM syndrome efficacy in the observation group was significantly superior to that in the control group(P＜0.01).(2)After 4 weeks of treatment,the hearing of patients in both groups was improved,and the total effective rate for the efficacy of hearing improvement in the observation group was 76.00%(38/50),while that in the control group was 46.00%(23/50).The intergroup comparison showed that the efficacy of hearing improvement in the observation group was significantly superior to that in the control group(P＜0.01).(3)After treatment,the TCM syndrome scores,DHI score,THI score and hearing VAS scores in the two groups were all decreased compared with those before treatment(P＜0.05 or P＜0.01),and the decrease in the observation group was significantly superior to that in the control group(P＜0.01).(4)After treatment,the average blood flow velocity of the left vertebral artery(LVA)and the right vertebral artery(RVA)in the two groups were both increased compared with those before treatment(P＜0.05),and the increase in the observation group was significantly superior to that in the control group(P＜0.05 or P＜0.01).(5)The results of 6-month follow-up after treatment showed that the incidence of Meniere's disease and the frequency of attack in the observation group were significantly reduced compared with those in the control group,and the episode duration in the observation group was significantly shorter than that in the control group,the differences being all statistically significant(P＜0.05 or P＜0.01).Conclusion Dingxuan Decoction combined with vestibular function rehabilitation training exert certain effect in treating patients with Meniere's disease of liver-kidney yin deficiency complicated with wind-water upward stirring type,and the therapy is effective on improving patients'clinical symptoms and vertebral artery blood flow,reducing the risk of recurrence and improving the quality of life of the patients.

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.