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.

Aim To establish a gait analysis system based on DeepLabCut(DLC)algorithm for evaluating motor function in aged mice.Methods Based on DLC algorithm in deep learning technology,treadmill device and fully closed design were used in the system,including software and hardware.This system was applied to evaluate gait characteristics of mice due to aging un-der different movement modes.Correlation analysis was used to explore the effects of body weight and body length on gait indica-tors.Results This system realized the synchronous analysis of three-dimensional gait(lateral and ventral plane)of mice at specific gait speed,and automatically quantified 47 gait indica-tors.Using this system,it was found that during walking(15 cm·s-1),the standard deviation of body turning angle decreased,forelimb sway duration,standard deviation of knee angle,mean outward angles of left and right hind paw increased in 8 and 15 month-old mice,compared with 2-month-old mice.However,15-month-old mice showed decreased walking frequency,and in-creased stride width,total duration of double support,and knee extension and contraction distance.In addition,at trot(20 cm·s-1),15-month-old mice were unable to walk steadily,and 8-month-old mice had increased total duration of double support and mean outward angles of left hind paw,compared with 2-month-old mice.Correlation analysis revealed that indicators like walking frequency,stride width,forelimb sway duration,total duration of double support,standard deviation of knee an-gle,knee extension and contraction distance,were not affected by changes in body weight and body length.Conclusions The gait analysis system based on DLC algorithm can achieve a more sensitive,accurate and comprehensive evaluation of the gait of aged mice,distinguishing the gait characteristics of aged mice to maintain gait stability,and selecting behavioral indicators that better reflect the gait changes of aged mice.It provides a meth-odological basis for more effective assessment of efficacy and side effects of drugs for anti-aging and anti-decline of motor coordina-tion in the future.

Objective To explore accuracy and clinical effect of robot-assisted implantation of sacroiliac penetrating screw in orthopedic surgery for posterior pelvic ring fracture.Methods The clinical data of 24 patients with posterior pelvic ring frac-ture treated with robot-assisted sacroiliac penetration screws from August 2022 to August 2023 were retrospectively analyzed,including 10 males and 14 females;aged from 21 to 73 years old with an average of(49.29±14.48)years old;according to Tile pelvic fractures,13 patients were type B and 11 were type C.The effect of screw placement was evaluated according to Gras criteria based on postoperative CT scan results.At the final follow-up,fracture healing was evaluated according to Matta score,and functional recovery was evaluated by Majeed score.Results All patients were followed up for 3 to 13 months with an aver-age of(6.00±3.28)months.Totally 36 sacroiliac penetrating screws,18 S1 penetrating screws,18 S2 penetrating screws were inserted,a total of 29 were excellent and 7 good according to Gras standard.Screw adjustment times was 0.00(0.00,0.75)times.At the final follow-up,Matta score was excellent in 18 patients,5 good and 1 moderate,and the maximum displacement distance was 2.55(0.00,5.65)mm.Majeed score was 84.37±8.38,15 patients were excellent,7 good and 2 moderate.Con-clusion Robot could accurately and safely assist in the placement of sacroiliac joint screws for the treatment of posterior pelvic ring fractures,and promote postoperative functional recovery of patients.

Due to the prominent unhealthy lifestyle of residents,accelerated population aging,and urbanization processes in our country,the impact of cardiovascular disease(CVD)risk factors on public health is becoming increasingly significant.The prevalence of cardiovascular disease(CVD)in China is still on the rise.It is estimated that there are 330 million people with CVD,including 13 million cases of stroke,11.39 million cases of coronary heart disease,8.9 million cases of heart failure,5 million cases of pulmonary heart disease,4.87 million atrial fibrillation,2.5 million cases of rheumatic heart disease,2 million cases of congenital heart disease,45.3 million cases of peripheral arterial disease,and 245 million cases of hypertension.The economic burden of CVD on residents and society is increasingly heavy,making it a significant public health issue.The turning point for the prevention and control of CVD has not yet arrived,and it is urgent to strengthen government-led efforts in CVD prevention and control.

Cases of human infection with H7 subtype avian influenza virus(AIV)combined with five NA subtypes(N2,N3,N4,N7,and N9)have been reported.This study was aimed at establishing a method for simultaneous detection and dif-ferential diagnosis of H7 and five NA subtypes of AIV.Seven pairs of specific primers were designed according to the conserved sequences of the HA gene of H7 subtype AIV,the NA gene of five NA AIV subtypes,and the M gene of all AIV subtypes.A high-throughput GeXP typing method was established for simultaneous detection of the H7 subtype and the five NA subtypes of AIV by using GeXP multiple gene expression and capillary electrophoresis analysis technology.The specificity and sensitivity of the method were determined,and clinical samples were tested.The specificity results indicated that this method was able to simultaneously detect seven target genes in a single tube;each pair of specific primers was able to detect the corresponding AIV subtype,and the universal detection primers were able to detect all subtypes of AIV,with no cross-reaction with other common avian disease pathogens.Sensitivity results demonstrated that this method was able to simultaneously detect seven target genes with a threshold detection limit was 100 copies/μL.The detection results for 150 clinical samples were consistent with those of viral isolation and identification.The high-throughput GeXP method for simultaneous differential diagnosis of the H7 subtype and five subtypes of AIV established in this study has advantages of high specificity,high sensitivity,rapidity,and simplicity,thus providing a new detection method for the effective prevention and control of AIV.

This study investigated the epidemiological and genotypic characteristics of group A rotavirus(RVA)in children under 5 years of age with diarrhea at a viral diarrhea surveillance sentinel hospital in Guangdong Province from 2021 to 2022,to provide a basis for RVA prevention and control.A total of 1 858 fecal samples from children under 5 years of age with diarrhea in 2021-2022 were collected.Rotavirus antigen was detected with ELISA,and positive samples were further sequenced and categorized.Among the 1 858 samples,156 were RVA positive.The positivity rates in boys and girls were 8.76％and 7.87％,respectively.Significant differences were observed in the detection rates of RVA infection among age groups.The rate of RVA infection increased gradually from December to April of the following year.In 2021,the main endemic strains of RVA in the Guangdong region were of the G9P[8]subtype,and the rare G8P[8]subtype increased in China.In 2022,the G8P[8]subtype surpassed the G9P[8]subtype for the first time.In cases of diarrhea in infants younger than 5 years in Guangdong Province from 2021 to 2022,the RVA genotypes were diverse,the G9P[8]genotype significantly decreased,and the G8P[8]subtype became a dominant genotype.Continuous RVA genotype monitoring remains necessary to assess the risk of RVA-related disea-ses.

The aim of this study is to investigate the immune effect of H9 subtype avian influenza virus(AIV)NP protein on mice and lay the foundation for the development of avian influenza vi-rus(AIV)vaccine.The H9N2 virus NP gene amplification product was cloned into the pET-32a expression vector,and the protein expression was verified by SDS-PAGE and Western blot,and the immune effect was evaluated by measuring the secretion of supernatant multicytokines in mouse splenocytes culture.The results showed that the total length of the coding region sequence of NP gene was 1 497 bp,NP recombinant proteins exist in both soluble and insoluble protein forms,and the specific bands were visible in Western blot.After immunizing mice,serum produces IgG-bind-ing antibodies with antibody titers of 1∶40 000.Compared with the control group,IL-2,IL-5 and IL-13 were significantly increased(P＜0.001),and the secretion of IL-6 was significantly increased compared with the control group.IL-4 and IL-12 p70 secretions were elevated compared with con-trols,but there was no significant difference.Compared with the control group,the secretions of IL-1β,IL-18,GM-CMF,TNF-α and IFN-γ were inhibited,but the difference was not significant(P＞0.05).The results showed that NP recombinant protein is a good immunogen,laying a foundation for in-depth research on influenza vaccine.

Objective To explore the correlation between colorectal cancer tissue Janus kinase 2(JAK2)gene mutations and T cytokine 3(TCF3)protein expression with clinical pathological characteristics and prognosis,and to provide laboratory reference indicators for early evaluation of the illness severity and prognosis of colorectal cancer.Methods A retrospective analysis was conducted on the data of 50 colorectal cancer patients who were admitted from January 2016 to April 2021 and retained colon cancer and adjacent tissue wax blocks.Basic information,clinical and pathological features such as TNM staging,lymph node metastasis,and 3-year survival prognosis of the patients were collected.The wax blocks of colon cancer and adjacent tissues of patients were detected,in which Taqman fluorescence probe method was applied to detect the distribution of JAK2 gene at the rs2230724 locus AA,AG,and GG genotypes in colon cancer tissues,and immunohistochemistry method was applied to detect the positive expression rate of TCF3 protein in colon cancer and adjacent tissues.The basic information,JAK2 rs2230724 gene mutation,and TCF3 protein expression of patients with different clinical and pathological characteristics were compared,and the influencing factors of clinical and pathological characteristics of colon cancer was analyzed by logistic regression model.Kaplan Meier survival curve was applied to compare the survival prognosis of patients with JAK2 gene mutations and TCF3 protein expression in colorectal cancer tissue,and Cox regression model was applied to analyze the risk factors affecting the prognosis of colorectal cancer patients.Results The positive expression rate of TCF3 protein in colon cancer tissues was higher than that in adjacent tissues(P＜0.05).The age,BMI,proportion of GG genotype at rs2230724 locus of JAK2 gene and positive expression rate of TCF3 protein in TNM stage Ⅲ colon cancer patients were higher than those in TNM stage Ⅰ-Ⅱ patients(P＜0.05);The age,BMI,smoking rate,proportion of GG type at the rs2230724 locus of JAK2 gene in colon cancer tissue,and positive expression rate of TCF3 protein in patients with lymph node metastasis were higher than those without lymph node metastasis(P＜0.05);The results of the logistic regression model analysis showed that the influencing factors of clinical pathological features such as TNM staging and lymph node metastasis in colon cancer were age,mutation of JAK2 gene rs2230724 site in colon cancer tissue,and positive expression rate of TCF3 protein(P＜0.05).The Kaplan Meier survival curve analysis showed that patients with JAK2 gene rs2230724 GG genotype and TCF3 protein positivity in colon cancer tissue had higher cumulative all-cause mortality rates(P＜0.05).The results of univariate and multivariate Cox regression model analysis showed that independent risk factors affecting the prognosis of colorectal cancer patients include JAK2 gene rs2230724 site GG type,TCF3 protein positive expression,TNM stage Ⅲ,lymph node metastasis,and age.Conclusion The proportion of JAK2 gene rs2230724 GG type and TCF3 protein expression in colorectal cancer tissues are related to their clinical pathological characteristics and prognosis,and can be used as reference indicators for evaluating clinical pathological characteristics and predicting prognosis of colorectal cancer.

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.