Electromagnetic fields can regulate the fundamental biological processes involved in bone remodeling. As a non-invasive physical therapy, electromagnetic fields with specific parameters have demonstrated therapeutic effects on bone remodeling diseases, such as fractures and osteoporosis. Electromagnetic fields can be generated by the movement of charged particles or induced by varying currents. Based on whether the strength and direction of the electric field change over time, electromagnetic fields can be classified into static and time-varying fields. The treatment of bone remodeling diseases with static magnetic fields primarily focuses on fractures, often using magnetic splints to immobilize the fracture site while studying the effects of static magnetic fields on bone healing. However, there has been relatively little research on the prevention and treatment of osteoporosis using static magnetic fields. Pulsed electromagnetic fields, a type of time-varying field, have been widely used in clinical studies for treating fractures, osteoporosis, and non-union. However, current clinical applications are limited to low-frequency, and research on the relationship between frequency and biological effects remains insufficient. We believe that different types of electromagnetic fields acting on bone can induce various “secondary physical quantities”, such as magnetism, force, electricity, acoustics, and thermal energy, which can stimulate bone cells either individually or simultaneously. Bone cells possess specific electromagnetic properties, and in a static magnetic field, the presence of a magnetic field gradient can exert a certain magnetism on the bone tissue, leading to observable effects. In a time-varying magnetic field, the charged particles within the bone experience varying Lorentz forces, causing vibrations and generating acoustic effects. Additionally, as the frequency of the time-varying field increases, induced currents or potentials can be generated within the bone, leading to electrical effects. When the frequency and power exceed a certain threshold, electromagnetic energy can be converted into thermal energy, producing thermal effects. In summary, external electromagnetic fields with different characteristics can generate multiple physical quantities within biological tissues, such as magnetic, electric, mechanical, acoustic, and thermal effects. These physical quantities may also interact and couple with each other, stimulating the biological tissues in a combined or composite manner, thereby producing biological effects. This understanding is key to elucidating the electromagnetic mechanisms of how electromagnetic fields influence biological tissues. In the study of electromagnetic fields for bone remodeling diseases, attention should be paid to the biological effects of bone remodeling under different electromagnetic wave characteristics. This includes exploring innovative electromagnetic source technologies applicable to bone remodeling, identifying safe and effective electromagnetic field parameters, and combining basic research with technological invention to develop scientifically grounded, advanced key technologies for innovative electromagnetic treatment devices targeting bone remodeling diseases. In conclusion, electromagnetic fields and multiple physical factors have the potential to prevent and treat bone remodeling diseases, and have significant application prospects.

BACKGROUND:There is still no consensus on the optimal internal fixation for the treatment of Pauwels Ⅲ femoral neck fracture,and most of the related finite element analyses have been performed using a single simplified loading condition,and the biomechanical properties of commonly used internal fixation devices need to be further investigated. OBJECTIVE:To analyze the biomechanical characteristics of Pauwels Ⅲ femoral neck fractures treated with cannulated compression screw,dynamic hip screw,and femoral neck system by finite element method under different loading conditions of single-leg standing loads and sideways fall loads. METHODS:The DICOM data of healthy adult femur were obtained by CT scanning,imported into Mimics 15.0 software to obtain the rough model of bone tissue.The data exported from Mimics were optimized by Geomagics software,and then three internal fixation models were built and assembled with the femur model according to the parameters of the clinical application of the cannulated compression screw,dynamic hip screw,and femoral neck system by using Pro/E software.Finally,the three internal fixation models were imported into Ansys software for loading and calculation to analyze the stress distribution and displacement of the femur and the internal fixation under different working conditions of single-leg standing loads and sideways fall loads,as well as the stress characteristics of the calcar femorale and Ward's triangle. RESULTS AND CONCLUSION:(1)Under the single-leg standing load and the sideways fall load,the proximal femoral stress of the three internal fixation models was mainly distributed above the fracture end of the femoral neck.The peak stress of the proximal femoral end,fracture end,Ward triangle,and calcar femorale of the three internal fixation models were the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(2)Under the single-leg standing load and the sideways fall load,the peak displacement of the proximal femur of the three internal fixation models was all located at the top of the femoral head,and the peak displacement was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(3)The peak displacement of the three internal fixation models was all located at the top of the internal fixation device under the single-leg standing and sideways fall loading conditions,and the peak displacement values were the smallest in the femoral neck system internal fixation model and the largest in the cannulated compression screw internal fixation model.(4)The internal fixation stress of the three internal fixation models was mainly distributed in the area near the fracture end of the internal fixation device under the single-leg standing and sideways fall loads,and the peak value of internal fixation stress was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(5)These results suggest that the mechanical stability of the femoral neck system is the best,but there may be a risk of stress shielding of the fracture end and calcar femorale.The stress of the internal fixation device of the femoral neck system is more dispersed,and the risk of internal fixation break is lower.

Objective: To investigate treatment strategies for chronic periapical periodontitis in prematurely erupted premolars and provide guidance for managing pulp and periapical diseases in young permanent teeth with immature roots. Methods: A regenerative endodontic procedure (REP) was performed on a prematurely erupted maxillary left first premolar (tooth 24) at Nolla stage Ⅶ with chronic apical periodontitis, following standardized protocols including root canal irrigation, disinfection, and coronal sealing. The case was followed up, and a literature review was conducted. Results: Clinical resolution of symptoms was observed on tooth 24, with sustained root development. After a 20-month follow-up, the tooth had restored biological function. Literature synthesis revealed that periapical infections in prematurely erupted permanent teeth predominently arise from pulp exposure and bacterial infection, with retrograde infection being rare. For young permanent teeth with necrotic pulp, regenerative endodontic procedures has been established as the treatment of choice to promote apical closure and root maturation. The critical steps of regenerative endodontic procedures include thorough disinfection, induced bleeding to form a fibrin scaffold, and coronal sealing to facilitate stem cell recruitment and differentiation. Conclusion Regenerative endodontic procedures represents an effective and viable treatment option for prematurely erupted young permanent teeth with chronic periapical periodontitis.

Pigeons show flocking and homing behaviors,which require characteristics including long-distance weight-bearing and continuous flight,with excellent navigation and spatial cognitive abilities.Pigeons have been widely used in animal robot research in recent years.Pigeon robots achieve motor behavior control by applying neural information intervention to specific neural targets in the pigeon's brain.This review summarizes research progress in pigeon robots based on the sensory system,motivation and emotional system or cortex and midbrain motor area respectively,according to the distribution of hierarchical multi-level neural regulatory targets in the pigeon's brain,with the aim of providing reference and guidance for further applied research into the use of pigeon robots in space perception,reconnaissance,and anti-terrorism search and rescue.

The biological clock(also known as the circadian rhythm)is the fundamental reliance for all organisms on Earth to adapt and survive in the Earth's rotation environment.Circadian rhythm is the most basic regulatory mechanism of life activities,and plays a key role in maintaining normal physiological and biochemical homeostasis,disease occurrence and treatment.Recent studies have shown that the biologi-cal clock plays an important role in the development of oral tissues and in the occurrence and treatment of oral diseases.Since there is cur-rently no guiding literature on the research methods of biological clock in stomatology,researchers mainly conduct research based on pub-lished references,which has led to controversy about the research methods of biological clock in stomatology,and there are many confusions about how to rationally apply the research methods of circadia rhythms.In view of this,this expert consensus summarizes the characteristics of the biological clock and analyzes the shortcomings of the current biological clock research in stomatology,and organizes relevant experts to summarize and recommend 10 principles as a reference for the rational implementation of the biological clock in stomatology research.

Purpose::To assess the value of the driving pressure variation rate (ΔP%) in predicting the outcome of weaning from invasive mechanical ventilation in patients with acute respiratory distress syndrome.Methods::In this case-control study, a total of 35 patients with moderate-severe acute respiratory distress syndrome were admitted to the intensive care unit between January 2022 and December 2022 and received invasive mechanical ventilation for at least 48 h were enrolled. Patients were divided into successful weaning group and failed weaning group depending on whether they could be removed from ventilator support within 14 days. Outcome measures including driving pressure, PaO 2:FiO 2, and positive end-expiratory pressure, etc. were assessed every 24 h from day 0 to day 14 until successful weaning was achieved. The measurement data of non-normal distribution were presented as median (Q 1, Q 3), and the differences between groups were compared by Wilcoxon rank sum test. And categorical data use the Chi-square test or Fisher's exact test to compare. The predictive value of ΔP% in predicting the outcome of weaning from the ventilator was analyzed using receiver operating characteristic curves. Results::Of the total 35 patients included in the study, 17 were successful vs. 18 failed in weaning from a ventilator after 14 days of mechanical ventilation. The cut-off values of the median ΔP% measured by Operator 1 vs. Operator 2 in the first 4 days were ≥ 4.17% and 4.55%, respectively ( p < 0.001), with the area under curve of 0.804 (sensitivity of 88.2%, specificity of 64.7%) and 0.770 (sensitivity of 88.2%, specificity of 64.7%), respectively. There was a significant difference in mechanical ventilation duration between the successful weaning group and the failure weaning group (8 (6, 13) vs. 12 (7.5, 17.3), p = 0.043). The incidence of ventilator-associated pneumonia in the successful weaning group was significantly lower than in the failed weaning group (0.2‰ vs. 2.3‰, p = 0.001). There was a significant difference noted between these 2 groups in the 28-day mortality (11.8% vs. 66.7%, p = 0.003). Conclusion::The median ΔP% in the first 4 days of mechanical ventilation showed good predictive performance in predicting the outcome of weaning from mechanical ventilation within 14 days. Further study is needed to confirm this finding.

Aim To explore the mechanism of the effect of rosiglitazone(Rsg)on the pancreatic cancer in diabetic mice based on the impact of PPARγ on glu-cose transport and metabolism.Methods A high-fat and high sugar diet combined with STZ was used to construct T2DM model;T2DM mice and normal mice were subcutaneously injected with PANC02 cells to construct a transplanted tumor model.T2DM trans-planted tumor mice and normal transplanted tumor mice were divided into the following groups:Rsg,PPARy inhibitor(PIN-2),rosiglitazone+PPARγ in-hibitor(Rsg+PIN-2),and normal transplanted tumor mice(NDM)and T2DM transplanted tumor mice(DM)were used as control groups,respectively.Tis-sue samples were collected after intervention.Tissue pathological changes were observed by HE staining.The expressions of Ki67 and PCNA proteins were de-tected by immunohistochemistry.Cell apoptosis was detected by TUNEL assay.The expression of PPARγwas detected by immunofluorescence.The expressions of Glucokinase,GLUT2,Nkx6.1,PDX-1RT-PCR were determined by Western blot.Results Rsg could significantly reduce the tumor mass,pathological chan-ges,Ki67 and PCNA expression of transplanted tumors(P＜0.05),increase cell apoptosis and the expression of PPARγ,Glucokinase,GLUT2,Nkx6.1,PDX-1 proteins in NDM and DM mice(P＜0.05).PIN-2 could reverse the indicator changes caused by Rsg in NDM and DM mice.However,compared with NDM mice,the above related indicators of the DM group mice were more sensitive to Rsg and PIN-2.Conclu-sions Compared to non-diabetic pancreatic cancer,rosiglitazone can more sensitively inhibit the prolifera-tion of pancreatic cancer with T2DM,induce apopto-sis,and reprogram the metabolism of pancreatic cancer with T2DM by activating PPA Rγ and altering the ex-pression of glucose and lipid metabolism genes,there-by exerting an anti-cancer effect.

Renying and Cunkou pulse diagnostic method is one of the important parts of the pulse diagnosis in Huangdi Neijing (Inner Canon of Yellow Emperor) and has been controversial since its proposal. This article takes WANG Shu-he's diagnostic operation as the evidence, and is in reference of the statement, "Cun region (the region ahead of Guan region of Cunkou) determines the human life, that on the left hand refers to Renying, while on the right hand is Qikou". The pulse conditions on the left and right hands represent yin and yang. If Renying pulse on the left is greater, the diseases are in yang meridians, while if Cunkou pulse on the right is bustling, the diseases are in yin meridians. By comparing the pulse condition and strength, as well as the pulse beating (rapid and urgent) between Guan region and region ahead of Guan on the same side, the conditions of three yang and three yin meridians are detected. In treatment, based on the records of Renying and Cunkou pulse diagnosis in Huangdi Neijing, the principles are proposed for reinforcing and reducing methods on hand and foot meridians of yin and yang. Five-shu points and yuan-source points are taken as the main acupoints in acupuncture treatment. During treatment, the changes in pulse conditions should be emphasized specifically and those at Renying and Cunkou regions are the criteria for judging qi arrival and qi regulation.
Humans ; Acupuncture Points ; Acupuncture Therapy ; Foot ; Hand ; Heart Rate

Humans ; Retrospective Studies ; Tetanus/epidemiology* ; China/epidemiology*