Melatonin (Mel) has been shown to have cardioprotective effects, but its action on ion channels is unclear. In this experiment, we investigated the inhibitory effect of Mel on late sodium currents (I_Na.L) in mouse ventricular myocytes and the anti-arrhythmic effect at the organ level as well as its mechanism. The whole-cell patch clamp technique was applied to record the ionic currents and action potential (AP) in mouse ventricular myocytes while the electrocardiogram (ECG) and monophasic action potential (MAP) were recorded simultaneously in mouse hearts using a multichannel acquisition and analysis system. The results demonstrated that the half maximal inhibitory concentration (IC₅₀) values of Mel on transient sodium current (I_Na.T) and specific I_Na.L opener 2 nmol·L^-1 sea anemone toxins II (ATX II) increased I_Na.L were 686.615 and 7.37 μmol·L^-1, respectively. Mel did not affect L-type calcium current (I_Ca.L), transient outward current (I_to), and AP. In addition, 16 μmol·L^-1 Mel shortened ATX II-prolonged action potential duration (APD), suppressed ATX II-induced early afterdepolarizations (EADs), and significantly reduced the incidence of ventricular tachycardia (VT) and ventricular fibrillation (VF) in Langendorff-perfused mouse hearts. In conclusion, Mel exerted its antiarrhythmic effects principally by blocking I_Na.L, thus providing a significant theoretical basis for new clinical applications of Mel. Animal welfare and experimental process are in accordance with the regulations of the Experimental Animal Ethics Committee of Wuhan University of Science and Technology (2023130).

Objective To analyze the epidemic situation and pathological characteristics of viral myocarditis in Wuxi region, laying the foundation for epidemiological research on viral myocarditis. Method A total of 8 000 patients with viral myocarditis from 2013 to 2022 were included. The basic data and infection status of patients diagnosed with viral myocarditis within 10 years were statistically analyzed, and the serum of the patients was tested for Coxsackie B virus nucleic acid. Results Viral myocarditis is mainly caused by Coxsackie B virus infection, with a confirmed positive rate of 69.24%. The main types of infected viruses are B3 and B4, with 29.31% and 33.87%, respectively. The infection of viral myocarditis varies with age, and the positive rate in children is higher at 69.29%, with statistical differences among different age groups（χ²=1210.344 , P<0.001）. The infection rate of Coxsackie B virus was 38.21% in males and 31.03% in females, with a statistically significant difference（χ²=155.032 , P<0.001）. Conclusion In the past 10 years, the infection rate of suspected viral myocarditis in children in Wuxi region has been higher than that in adults, and the incidence of COVID-19 B group virus infection is higher in men, with B3 and B4 being the main cases. It is necessary to increase prevention efforts in children and young men.

Objective To analyze the feasibility and efficacy of a deep convolutional neural network(DCNN)model based on chest CT images to evaluate bone mineral density(BMD).Methods A total of 1 048 health check subjects'2 096 central level images of lumbar 1 and 2 vertebral bodies were used for experiments and analysis in this retrospective study.According to the results of quanti-tative computed tomography(QCT)BMD measurement,the subjects were divided into three categories:normal,osteopenia,osteopo-rosis(OP).Herein,a DCNN segmentation model was constructed based on chest CT images[training set(n=1 096),tuning set(n=200),and test set(n=800)],the segmentation performance was evaluated using the Dice similarity coefficient(DSC)to com-pare the consistency with the manually sketched region of vertebral body.Then,the DCNN classification models 1(fusion feature construction of lumbar 1 and 2 vertebral bodies)and model 2(image feature construction of lumbar 1 alone)was developed based on the training set(n=530).Model performance was compared in a test set(n=418)by the receiver operating characteristic(ROC)curve analysis.Results When the number of images in the training set(n=300)was adopted,the DSC value was 0.950 in the test set.The results showed that the sensitivity,specificity and area under the curve(AUC)of model 1 and model 2 in diagno-sing osteopenia and OP were 0.716,0.960,0.952;0.941,0.948,0.980;0.638,0.954,0.940;0.843,0.959,0.978,respectively.The AUC value of normal model 1 was higher than that of model 2(0.990 vs 0.983,P=0.033),while there was no significant difference in AUC values between osteopenia and OP(P=0.210,0.546).Conclusion A DCNN may have the potential to evaluate bone mass based on chest CT images,which is expected to become an effective tool for OP screening.

With a global rise in morbidity rates， obesity has become a pressing public health issue. With increased adipocyte number and volume as the main characteristics， obesity is also manifested by metabolic disorders to varying degrees. At the same time， obesity is a risk factor for diabetes， hypertension， stroke， cancer， and cardiovascular diseases， imposing burdens on society and families. Influenced by lifestyle， environment， behavior， and genetics， obesity is caused by the interaction of many factors， and its pathological process is complex， involving inflammation， autophagy， and intestinal dysbiosis. The mitogen-activated protein kinase （MAPK） cascade reaction， a pivotal signaling pathway， plays a crucial role in cellular processes such as proliferation， differentiation， apoptosis， and stress responses. Both Chinese and international studies indicate that the MAPK signaling pathway can effectively regulate obesity through various pathways， including the modulation of adipocyte differentiation and apoptosis， appetite control， and inflammation improvement. Moreover， traditional Chinese medicine （TCM） has demonstrated significant efficacy in preventing and treating obesity， leveraging advantages such as multiple targets， diverse components， and minimal adverse effects. Research indicates that the MAPK signaling pathway is a primary focus of TCM regulation in this context， although a systematic review in this field is currently lacking. Therefore， this paper， by reviewing the latest Chinese and international research， provided a concise overview of the basic structure of the MAPK pathway， with a specific emphasis on recent progress in TCM interventions targeting the MAPK pathway for obesity treatment. The results indicate that regulating adipose tissue formation， differentiation， and thermogenesis， reducing inflammation and oxidative stress levels， and improving insulin sensitivity and metabolic disorders seem to be the main ways for TCM to regulate the MAPK pathway to prevent and treat obesity. However， it is necessary to find more research methods and explore potential mechanisms underlying TCM formulations based on the MAPK pathway for obesity prevention and treatment.

Regenerative medicine focuses on replacing and repairing damaged tissues and organs to restore their normal structure and function.Common techniques in regenerative medicine include tissue engineering,organ transplantation,and cell-free therapy.Cell-free therapy has gained attention due to its potential to reduce immune rejection and tumorigenicity,emerging as a prominent area in regenerative medicine research.The advancement of cell-free therapy has been facilitated by the discovery of extracellular vesicles(EVs),which are small membranous structures released by cells and play crucial roles in intercellular communication.EVs show promise as therapeutic agents and drug delivery vehicles.However,challenges such as short half-life,lack of targeting,and poor retention hinder their effectiveness.Hydrogels offer a solution by enhancing the stability and retention of EVs in vivo,thereby improving their therapeutic potential.In this context,researchers have explored hydrogel-based delivery systems for EVs.This review systematically summarizes recent developments in hydrogel-based EVs delivery systems within the field of regenerative medicine,highlighting both opportunities and challenges for clinical applications.

Objective To investigate the ameliorative effect of ginsenoside Rf on endometriosis(EMS)and its mechanism.Methods In animal experiments,Wistar female rats were randomly divided into sham group(laparotomy without other treatment),model group(EMS construction),low dose group(1.0 mg·kg-1 ginsenoside Rf),middle dose group(2.0 mg·kg-1 ginsenoside Rf),high dose group(3.0 mg·kg-1 ginsenoside Rf),positive group(0.25 mg·kg-1 pregnrienone capsule).The volume of ectopic lesions and the number of painful twisting were detected;the apoptosis rate in tissues was detected by TdT mediated dUDP nick end labeling(Tunel)assay;the expression of related proteins in each group was detected by Western blot assay.Cell experiment:The isolated primary rat endometrial cells were randomly divided into control group(normal tissue isolation),EMS group(EMS cells),Rf group(20 μmol·L-1 ginsenoside Rf treated EMS cells),combined group(20 μmol·L-1 ginsenoside Rf and 50 μmol·L-1 autophagy inhibitor 3-MA treated EMS cells).Western blot assay was used to detect the expression of related proteins;flow cytometry was used to detect apoptosis.Results Animal experiment:The times of body twisting in sham group,model group,high dose group and positive group were 0,37.10±4.64,14.70±1.90 and 20.20±1.78,respectively;the ectopic lesion volumes were 0,(118.91±19.51),(50.11±9.69)and(37.64±3.56)mm,respectively;the apoptosis rates were(3.43±0.33)％,(3.22±0.27)％,(20.42±1.82)％and(22.92±2.67)％,respectively;Beclin 1 protein expression were 0.32±0.03,0.36±0.04,0.79±0.12,0.35±0.07,respectively;glutathione peroxidase 4(GPX4)protein expression were 1.10±0.07,0.94±0.11,0.53±0.03,0.96±0.16,respectively.The above indexes of the model group were compared with those of the sham group,and the above indexes of the high dose group were compared with those of the model group,and the differences were significant(all P＜0.05).Cell experiment:Beclin1 protein expression in control group,EMS group,Rf group and combined group were 0.22±0.05,0.31±0.03,0.52±0.07 and 0.19±0.03,respectively;GPX4 protein expression were 0.97±0.07,0.81±0.09,0.63±0.05 and 1.05±0.09,respectively;the apoptosis rates were(3.48±0.04)％,(3.42±0.23)％,(21.66±2.95)％and(12.51±1.15)％,respectively;the above indexes in Rf group were compared with those in EMS group,and the above indexes in combined group were compared with those in Rf group,and the differences were significant(all P＜0.05).Conclusion Ginsenoside Rf can improve endometrial lesion,pain sensitivity and apoptosis in EMS rats,which may be related to the regulation of autophagy dependent ferroptosis.

Objective To investigate the effects of exercise and complex environment on lipopolysaccharide(LPS)-induced dopaminergic neuron death in the substantia nigra of midbrain.Methods C57BL/6 mice were divided into control group,LPS group,LPS+swimming group and LPS+complex environment group,with 7 mice in each group.The mice in the LPS group were injected with LPS into the brain to establish an inflammatory model of Parkinson's disease and lived in cages for 2 weeks.Mice in LPS+swimming group were forced to swim for 15 minutes every day for 2 weeks after modeling.The mice in the LPS+complex environment group were placed in a complex environment for 2 weeks after modeling.The control group mice were not treated.After 14 days of modeling,behavioral experiments such as footprint,open field and rotating rod were performed on each group of mice to detect the autonomous exercise ability,exercise balance ability and depression level of mice.The expressions of tyrosine hydroxylase(TH)in substantia nigra was detected by immunohistochemical staining and Western blotting.The expressions of brain-derived neurotrophic factor(BDNF),Caspase-3,interleukin-1β(IL-1β),interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)in the substantia nigra of the midbrain were detected by Western blotting.The transcription levels of IL-1β,IL-6 and TNF-α in substantia nigra were detected by RT-PCR.Results Compared with the control group,the exercise ability and balance ability of mice in LPS group,LPS+swimming group and LPS+complex environment group decreased,the depression level increased(P＜0.001),the number of TH positive neurons and BDNF protein decreased significantly(P＜0.001),and the contents of Caspase-3,IL-1β,IL-6 and TNF-α increased significantly(P＜0.001).Compared with the LPS group,the exercise ability and balance ability of the mice in the LPS+swimming group and the LPS+complex environment group were restored,the depression level decreased significantly(P＜0.01),the survival number of TH positive neurons and the content of BDNF increased significantly(P＜0.01),Caspase-3,IL-1β,IL-6 and TNF-α reduced significantly(P＜0.01),and the phenomenon in the LPS+complex environment group was more significant.Conclusion Exercise and complex environment can inhibit LPS-induced central nervous system inflammation in mice,thereby reducing damage to midbrain substantia nigra neurons,and the inhibitory effect of LPS+complex environment group is more significant.

The steps for installation and withdrawal of WYD2000 field surgical lamp were introduced.The failures and causes of broken cross-arm connector of WYD2000 field surgical lamp were analyzed.The problems of WYD2000 field surgical lamp in vulnerability to breaking and difficulty in maintenance were solved by designing and manufacturing a special maintenance tool and optimizing the materials and fixing mode of cross-arm connection.References were provided for main-tenance and improvement of WYD2000 field surgical lamp.[Chinese Medical Equipment Journal,2024,45(4):116-118]

Objective To investigate the effect of reducing the image-guided X-ray field area on the accuracy of Cyberknife radiotherapy,in order to provide a feasible method for achieving patient protection optimization.Methods Firstly,the spine-tracking,fiducial tracking and lung-tracking radiotherapy plans were formulated for the simulation phantom,and then image-guided full-field localization and position pre-setting were carried out for the simulation phantom,and the spine-tracking,fiducial tracking and lung-tracking radiotherapy plans were executed for the simulation phantom using a reduced lead block field area,respectively.Secondly,the radiotherapy accuracy of different radiotherapy plans was verified by end-to-end(E2E)software using new EBT films of the same batch as the base film.Finally,the changes of the simulation phantom were compared in terms of position pre-presetting error,radiotherapy accuracy and lead block field area.Results The spine-tracking and fiducial tracking radiotherapy plans had the translation errors not higher than 0.1 mm and the rotation errors not higher than 0.1°,which were comparable to the fluctuated conventional Cyberknife image-guided locating;the spine-tracking,fiducial tracking and lung-tracking radiotherapy plans had the lead block field radiotherapy accu-racies being 0.71,0.18 and 1.06 mm,respectively,which met the clinical requirements for Cyberknife radiotherapy;the lead block field areas of the spine-tracking,fiducial tracking and lung-tracking radiotherapy plans were reduced to 19.75％,29.28％and 12.71％of the full field area,respectively,and the efficacy for field area optimization was significant.Conclusion It's feasible to involve a reduced image-guided X-ray field area in Cyberknife radiotherapy,which contributes to optimizing radiation protection for the patients.[Chinese Medical Equipment Journal,2024,45(11):49-53]

Objective To investigate the prevalence of tension-type headache(TTH)in children and adolescents aged 0-19 years globally in 1990-2021,and to provide a basis for the prevention and treatment of TTH.Methods Based on the Global Burden of Disease Study data,the age-standardized prevalence distribution of TTH and its changing trend were analyzed among the children and adolescents aged 0-19 years,with different sexes,age groups,sociodemographic index(SDI)regions and countries/territories.Results The age-standardized prevalence rate(ASPR)of TTH in children and adolescents aged 0-19 globally in 2021 was 17 339.89/100 000,which was increased by 1.73%since 1990.The ASPR in females was slightly higher than that in males(1990:17 707.65/100 000 vs 16 403.78/100 000;2021:17 946.29/100 000 vs 16 763.09/100 000).The ASPR in adolescence was significantly higher than that in school-aged and preschool periods(1990:27 672.04/100 000 vs 10 134.16/100 000;2021:28 239.04/100 000 vs 10 059.39/100 000).Regions with high SDI exhibited a higher ASPR than the other regions,with significant differences in prevalence rates across different countries.From 1990 to 2021,there was a slight increase in global ASPR,with an average annual percentage change(AAPC)of 0.06%.Females experienced a smaller increase than males based on AAPC(0.04%vs 0.07%).There was reduction in ASPR in preschool and school-aged groups,with an AAPC of-0.02%,while there was a significant increase in ASPR in adolescence,with an AAPC of 0.07%.ASPR decreased in regions with low-middle and low levels of SDI,with an AAPC of-0.02%and-0.04%,respectively,while it increased in regions with middle SDI,with an AAPC of 0.24%.Conclusions There is a consistent increase in the ASPR of TTH in children and adolescents aged 0-19 years globally,with significant differences across sexes,age groups,SDI regions and countries/territories.