BACKGROUND:Orthodontic treatment to move the mandibular second molar in place of the missing first molar is a good method for preserving natural teeth.However,molars often exhibit mesial tipping when using clear aligners.The impact of attachments and overcorrection on the molar mesialization with clear aligners is unclear.OBJECTIVE:To investigate the effects of attachments and overcorrection on displacement and biomechanics of the mandibular second molar mesialization.METHODS:A finite element model with the left mandibular first molar missing was constructed using a volunteer's cone-beam CT and intraoral scan data.The experiment was divided into four groups based on the position of attachments on the left mandibular second molar:without attachment,buccal attachment,lingual attachment,and buccal-lingual attachment,with overcorrection degrees(0°,1°,2°,3°,and 4°)for each group,totaling 20 models.The calculation and analysis of the displacement trends and stress were performed using Abaqus software.RESULTS AND CONCLUSION:(1)Mesial tipping and intrusion of the molar,distal tipping of the canines and permolars,and linguaing of the incisors occurred during molar mesialization.(2)The displacement of molars increased when attachments were used,with the maximum displacement occurring when buccal-lingual attachments were applied.Molars tended to tip towards the side without attachments when attachments were designed unilaterally.However,the inclination of molars did not decrease when attachments were used.(3)Molars exhibited reduced mesial tipping and intrusion,approaching overall movement,and the stress of periodontal ligament was relieved and more evenly distributed during overcorrection treatment,and this effect became more pronounced with increased degrees of overcorrection.(4)Attachments can enhance the effectiveness of overcorrection,with the best performance observed when buccal-lingual attachments are used.Using attachments and overcorrection together helps control molar mesial tipping and intrusion,but overall molar movement is not achieved.

BACKGROUND:The lactate threshold is a crucial physiological indicator for assessing the aerobic metabolic capacity and training level of endurance athletes,representing the intensity point at which lactate production and clearance reach a dynamic equilibrium within the organism.The traditional lactate threshold training,which is a prolonged and stable-intensity training,aims to enhance the aerobic endurance and lactate clearance efficiency of athletes.In recent years,with the advancement of exercise physiology,double lactate threshold training has emerged as an innovative training modality,drawing extensive attention from both the academic circle and practitioners.Nevertheless,current systematic research on double lactate threshold training remains limited,particularly in aspects such as its physiological mechanisms,optimal implementation plans,and long-term effects.OBJECTIVE:To systematically sort out the development course of double lactate threshold training,deeply analyze its fundamental connotations,objectively assess its application effects,and investigate its physiological action mechanisms,with the expectation of providing scientific basis and guidance for the improvement and optimization of endurance sports training theories and practices.METHODS:With the search terms of"lactate threshold training,double lactate threshold training,lactate training,threshold training,endurance training,Norwegian training method,Norwegian training mode,Norwegian training experience,"a systematic search was conducted in databases,including PubMed,Web of Science,Embase,Medline,Cochrane Library,CNKI,WanFang,and VIP.After screening,8articles met the requirements,involving 8 training cases,and 14 top international athletes,and sports events include 800 m,1 500 m,5 000 m,10 000 m,and cross-country running(9.5 km for men and 4.5 km for women).RESULTS AND CONCLUSION:(1)For the first time,double lactate threshold training was defined as a training strategy aimed at improving aerobic and speed capabilities,involving separate aerobic and anaerobic threshold training sessions within a single training day(aerobic training load intensity requirement of 0.7-2.0 mmol/L,anaerobic training load intensity requirement of 2.0-4.5 mmol/L),with a training frequency of＞2 times per week and a training volume of 120-160 km per week.(2)Double lactate threshold training has positive effects on muscle adaptability and plasticity(dimension and elasticity),increasing aerobic and anaerobic capabilities,and alleviating central neural fatigue and peripheral fatigue.(3)The main mechanisms by which double lactate threshold training yields effects may include hormone secretion,protein synthesis and inhibitory regulation,muscle fiber recruitment and cell swelling,mitochondrial biosynthesis and improvement in the chain of respiratory function,and neurotransmitter regulation.(4)In the practical application of double lactate threshold training,factors such as individualized training plans,load intensity design and monitoring for threshold training days,and applicable sports events should be fully considered.For the systematic improvement of double lactate threshold training,further exploration is still needed in terms of application subjects,training plans,action mechanisms,effect evaluation,and safe application.

BACKGROUND:In China,the patient population with osteonecrosis is large,and there is an urgent need to find new preventive targets to develop more effective treatment strategies.Metabolomics studies have shown that there is an association between human metabolites and osteonecrosis,but the causal relationship between blood metabolites and osteonecrosis has not yet been clarified.OBJECTIVE:To investigate the causal relationship between blood metabolites and osteonecrosis through two-sample Mendelian randomization analysis.METHODS:The public data of 486 blood metabolites(exposure factors)and osteonecrosis(outcome factors)were collected.Data of 486 blood metabolites were derived from a genome-wide association estimate for blood metabolites published in Nature Genetics in 2014,which covered 7 824 European adults.The single nucleotide polymorphism data for osteonecrosis were obtained from the FinnGen public database R11 dataset,containing information on a total of 431 614 samples and 21 306 430 single nucleotide polymorphism loci,with 1 788 cases of osteonecrosis and 429 826 controls,with all participants being of European descent.Mendelian randomization analysis(inverse variance weighting method,MR-Egger method,and weighted median method)was performed by Rstudio software,and then the heterogeneity test,horizontal pleiotropy test and Steiger directionality test were performed to ensure the robustness and reliability of the results.RESULTS AND CONCLUSION:(1)Sixteen blood metabolites were identified as having a significant causal relationship with osteonecrosis(Pinverse variance weighting＜Pfalse discovery rate＜0.05).(2)Eight blood metabolites increased the risk of osteonecrosis(including four known metabolites and four unknown metabolites),specifically pantothenate,beta-hydroxyisovalerate,hippurate,salicyluric glucuronide,X-08766,X-11452,X-12776 and X-14662.(3)Eight blood metabolites could reduce the risk of osteonecrosis(six known metabolites and two unknown metabolites),including cortisol,1-palmitoylglycerol(1-monopalmitin),pyroglutamyl glycine,2-stearoylglycerophosphocholine,p-cresol sulfate,ergothioneine,X-06307,X-12092.(4)The above results suggest that there is a causal relationship between 16 blood metabolites and osteonecrosis,which is expected to be a potential target for intervention in the occurrence and treatment of osteonecrosis in the future.(5)Despite the lack of relevant data from large-scale Asian populations at present,this study provides important reference value for the field of osteonecrosis in China based on European population data.In the future,domestic medical workers may be able to achieve precise intervention for osteonecrosis by regulating metabolite levels.In addition,based on the results of this study,relevant researchers can further explore the mechanism of action of metabolites in the treatment of osteonecrosis with traditional Chinese medicine,which not only helps to deepen the understanding of traditional Chinese medical therapies but also promotes the progress of integrated traditional Chinese and Western medicine research,driving the development of personalized treatment plans that are more suitable for the characteristics of the Chinese population.

BACKGROUND:Orthodontic treatment to move the mandibular second molar in place of the missing first molar is a good method for preserving natural teeth.However,molars often exhibit mesial tipping when using clear aligners.The impact of attachments and overcorrection on the molar mesialization with clear aligners is unclear.OBJECTIVE:To investigate the effects of attachments and overcorrection on displacement and biomechanics of the mandibular second molar mesialization.METHODS:A finite element model with the left mandibular first molar missing was constructed using a volunteer's cone-beam CT and intraoral scan data.The experiment was divided into four groups based on the position of attachments on the left mandibular second molar:without attachment,buccal attachment,lingual attachment,and buccal-lingual attachment,with overcorrection degrees(0°,1°,2°,3°,and 4°)for each group,totaling 20 models.The calculation and analysis of the displacement trends and stress were performed using Abaqus software.RESULTS AND CONCLUSION:(1)Mesial tipping and intrusion of the molar,distal tipping of the canines and permolars,and linguaing of the incisors occurred during molar mesialization.(2)The displacement of molars increased when attachments were used,with the maximum displacement occurring when buccal-lingual attachments were applied.Molars tended to tip towards the side without attachments when attachments were designed unilaterally.However,the inclination of molars did not decrease when attachments were used.(3)Molars exhibited reduced mesial tipping and intrusion,approaching overall movement,and the stress of periodontal ligament was relieved and more evenly distributed during overcorrection treatment,and this effect became more pronounced with increased degrees of overcorrection.(4)Attachments can enhance the effectiveness of overcorrection,with the best performance observed when buccal-lingual attachments are used.Using attachments and overcorrection together helps control molar mesial tipping and intrusion,but overall molar movement is not achieved.

BACKGROUND:The lactate threshold is a crucial physiological indicator for assessing the aerobic metabolic capacity and training level of endurance athletes,representing the intensity point at which lactate production and clearance reach a dynamic equilibrium within the organism.The traditional lactate threshold training,which is a prolonged and stable-intensity training,aims to enhance the aerobic endurance and lactate clearance efficiency of athletes.In recent years,with the advancement of exercise physiology,double lactate threshold training has emerged as an innovative training modality,drawing extensive attention from both the academic circle and practitioners.Nevertheless,current systematic research on double lactate threshold training remains limited,particularly in aspects such as its physiological mechanisms,optimal implementation plans,and long-term effects.OBJECTIVE:To systematically sort out the development course of double lactate threshold training,deeply analyze its fundamental connotations,objectively assess its application effects,and investigate its physiological action mechanisms,with the expectation of providing scientific basis and guidance for the improvement and optimization of endurance sports training theories and practices.METHODS:With the search terms of"lactate threshold training,double lactate threshold training,lactate training,threshold training,endurance training,Norwegian training method,Norwegian training mode,Norwegian training experience,"a systematic search was conducted in databases,including PubMed,Web of Science,Embase,Medline,Cochrane Library,CNKI,WanFang,and VIP.After screening,8articles met the requirements,involving 8 training cases,and 14 top international athletes,and sports events include 800 m,1 500 m,5 000 m,10 000 m,and cross-country running(9.5 km for men and 4.5 km for women).RESULTS AND CONCLUSION:(1)For the first time,double lactate threshold training was defined as a training strategy aimed at improving aerobic and speed capabilities,involving separate aerobic and anaerobic threshold training sessions within a single training day(aerobic training load intensity requirement of 0.7-2.0 mmol/L,anaerobic training load intensity requirement of 2.0-4.5 mmol/L),with a training frequency of＞2 times per week and a training volume of 120-160 km per week.(2)Double lactate threshold training has positive effects on muscle adaptability and plasticity(dimension and elasticity),increasing aerobic and anaerobic capabilities,and alleviating central neural fatigue and peripheral fatigue.(3)The main mechanisms by which double lactate threshold training yields effects may include hormone secretion,protein synthesis and inhibitory regulation,muscle fiber recruitment and cell swelling,mitochondrial biosynthesis and improvement in the chain of respiratory function,and neurotransmitter regulation.(4)In the practical application of double lactate threshold training,factors such as individualized training plans,load intensity design and monitoring for threshold training days,and applicable sports events should be fully considered.For the systematic improvement of double lactate threshold training,further exploration is still needed in terms of application subjects,training plans,action mechanisms,effect evaluation,and safe application.

Objective: To investigate the relationship between physical development indicators and the onset and progression of myopia among children and adolescents, so as to provide theoretical support for coordinated vision and physical health management. Methods: A prospective cohort study was conducted. In September 2022, 3 102 students from grade one in primary school to grade three in junior high school (five year primary school and four year junior high school) from six schools in Huantai County, Shandong Province, were selected using multistage cluster random sampling method to participate in an epidemiological survey on myopia, with follow up completed in September 2023. Follow up value minus baseline value( d ) was used to assess changes in physical development and vision indicators. Multivariate Logistic regression analysis was used to examine the relationship between physical development indicators and the incidence of myopia. Generalized linear models were established to analyze the relationship between physical development indicators and changes in d spherical equivalent (SE) and d axial length (AL) . Results: Multivariate Logistic regression analysis showed that, after adjusting for factors such as gender, age, and baseline body mass index, the third ( Q 3)and fourth ( Q 4)quartiles of d height showed increased risks of myopia onset within one year compared to the first quartile( Q 1) ( OR =1.85,95% CI =1.18-2.88; OR =1.74,95% CI =1.09-2.78,both P ＜0.05). Results from the generalized linear model indicated that, after adjusting for confounding factors such as gender, age, and baseline SE, d SE was negatively correlated with d height and d weight in children and adolescents ( β =-0.024, 95% CI =-0.031 to -0.018; β =-0.006, 95% CI =-0.011 to -0.001), d AL was positively correlated with d height and d weight in children and adolescents ( β =0.011, 95% CI =0.008-0.013; β =0.005, 95% CI =0.003-0.007) (all P ＜0.05). Conclusions Physical development indicators in children and adolescents were associated with the onset and progression of myopia. Dynamic monitoring and early intervention of myopia should be strengthened for children and adolescents with rapid height and weight gain to achieve coordinated management of myopia and physical development.

Objective Rapid eye movement sleep behavior disorder（RBD） is a common sleep disorder in the elderly， and this study aims to investigate the activity of cerebral cortex based on the changes in electroencephalography （EEG） power spectrum and the difference in approximate entropy during the ictal period of RBD. Methods A total of 35 patients with idiopathic RBD who received video polysomnography monitoring were enrolled as RBD group， and 25 normal volunteers matched for age were enrolled as control group.REM EEG results with fewer artifacts was selected for both groups， and the RBD group had an increase in mandibular electromyographic activity or dream-enacting behaviors. The leads containing artifacts were excluded， and finally O1 （or O2 alternative） leads with relatively little interference were selected. After pretreatment， Fourier transform was performed for EEG data from both groups to calculate the absolute power and relative power ratio of EEG in five different frequency bands， i.e.， δ （0.5-3 Hz）， θ （4-7 Hz）， α （8-13 Hz）， β （14-30 Hz）， and γ （30-35 Hz）. The normal distribution of power values in each frequency band was tested for both groups， and the t-test was used for comparison. Approximate entropy was calculated for EEG in both two groups， and the t-test was used for comparison. Results The θ band was the dominant frequency band of REM EEG in both the control group and the RBD group. Compared with the control group， the RBD group had a significant increase in the absolute power of fast-wave activity on REM α band and significant reductions in δ/α and θ/α relative power ratios. There was a significant difference in EEG ApEn value between the control group and the RBD group （P<0.05）， and the RBD group had a higher ApEn value during REM sleep than the NC group， with a significant difference in EEG ApEn value during the phase of dream-enacting behaviors. Conclusion In the RBD group， there are significant increases in the absolute power and nonlinear approximate entropy of fast-wave activity on REM α band during the ictal period of REM， which reflects the hyperactive functional changes of cerebral cortex during the ictal period of RBD， and the involvement of cerebral cortex in RBD neural pathway disorders is an important supplement to the current theory. Moderate inhibition of cerebral cortex hyperactivity is of great significance for the treatment of RBD.

[摘 要] 目的：旨在构建Trop2-ECD与幽门螺杆菌铁蛋白（HPF）融合纳米颗粒疫苗，并评价其免疫原性与抗三阴性乳腺癌（TNBC）活性。方法：构建Trop2-ECD_HPF纳米颗粒疫苗，并在293F细胞中表达和纯化。通过尺寸排阻色谱和透射电子显微镜验证疫苗的纯度和均一性。使用铝佐剂配制疫苗对雌性BALB/c小鼠进行免疫，通过酶联免疫吸附法（ELISA）检测血清中Trop2特异性抗体滴度，并评估其对4T1-Trop2肿瘤模型的抑制效果。结果：Trop2-ECD_HPF纳米颗粒粒径约20 nm，颗粒形成率较高，纯度较高，能够显著诱导小鼠产生高滴度的Trop2特异性抗体，疫苗组第6周抗体滴度达106，显著高于佐剂组（P < 0.000 1）。在动物实验中，疫苗组小鼠的肿瘤体积显著减小（抑瘤率为38.6%），肿瘤增长速度显著减缓（P < 0.001），显示出较强的抗肿瘤效果。结论：Trop2-ECD_HPF融合纳米颗粒疫苗可有效诱导特异性体液免疫应答，显著抑制TNBC生长，为靶向Trop2的纳米疫苗开发提供了实验依据。

ObjectiveTo explore the mechanism of Yishen Qubi Tongluo Formula （益肾祛痹通络方， YQTF） in the treatment of rheumatoid arthritis（RA）. MethodsNetwork pharmacology was employed to retrieve and screen the active components and potential targets of YQTF as well as RA-related targets using databases including TCMSP， BATMAN， ETCM and GEO. The intersection of targets related to active components and RA-related targets was identified， and a protein-protein interaction （PPI） network was constructed. Gene Ontology （GO） functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analysis were performed， and a drug-active component-common target network of YQTF in the treatment of RA was established. The core components of YQTF were molecularly docked with key targets. Human rheumatoid arthritis synovial fibroblast cell line MH7A was divided into blank group， model group， methotrexate group and YQTF group. The blank group was cultured with 10% fetal bovine serum， while the other three groups were stimulated with 10 μg/L of recombinant human tumor necrosis factor-α （TNF-α） for 24 h to establish the RA cell model. On this basis， the methotrexate group was treated with methotrexate suspension at a concentration of 20 μmol/L， and the YQTF group was treated with 10% YQTF-medicated serum. After 48 h of intervention， the levels of TNF-α and interleukin-17A（IL-17A）contents in cell supernatants were detected by enzyme-linked immunosorbent assay （ELISA）， and mRNA expressions of phosphatidylinositol 3-kinase（PI3K）， protein kinase B（AKT） and mammalian target of rapamycin（mTOR） were detected by real-time quantitative polymerase chain reaction （RT-qPCR）. ResultsNetwork pharmacological analysis identified 209 active components and 583 potential target genes of YQTF， as well as 818 RA-related targets. A total of 29 common targets were obtained from the intersection of drug-related targets and RA-related targets. Quercetin，β-sitosterol， kaempferol， stigmasterol and luteolin were the core active components of YQTF for the treatment of RA， while matrix metalloproteinase-9 （MMP9）， prostaglandin-endoperoxide synthase 2 （PTGS2）， Toll-like receptor 4 （TLR4）， tumor protein p53 （TP53） and transcription factor AP-1 subunit JUN were the key targets. The GO and KEGG pathway enrichment analysis showed that the involved biological processes and pathways were mainly associated with antioxidant responses， PI3K-AKT signaling pathway and Toll-like receptor （TLR） signaling pathway. Molecular docking results showed that MMP9 and PTGS2 exhibited high binding affinities with quercetin， β-sitosterol， kaempferol， stigmasterol and luteolin； TLR4 exhibited high binding activities with β-sitosterol， stigmasterol and luteolin； and TP53 showed high binding affinity with luteolin. The results of cell experiments showed that compared with the control group， the contents of TNF-α and IL-17A as well as the mRNA expressions of AKT and mTOR in the model group significantly increased （P＜0.05 or P＜0.01）. Compared with the model group， all the above indicators significantly decreased in the YQTF group， while the contents of TNF-α and the mRNA expression of AKT significantly decreased in the methotrexate group （P＜0.05 or P＜0.01）. ConclusionThe mechanism of YQTF in the treatment of RA may be associated with reducing inflammatory cytokine secretion and inhibiting the activation of the PI3K-AKT-mTOR signaling pathway.

Objective To study the photodynamic performance and the killing effect of photodynamic therapy on lung cancer of novel chlorin compounds 2-（4-（5,15,20-triphenyl-7H,8H-porphyrin-10-yl） phenoxy） acetic acid（D1）and 4-（4-（5,15,20-triphenyl-7H,8H-porphyrin-10-yl） phenoxy） butanoic acid （D2）. Methods The ultraviolet visible absorption spectrum and fluorescence spectrum of D1 and D2 were determined. The singlet oxygen generation capacity of D1 and D2 was measured by using DPBF as singlet oxygen capture agent. Fluorescence assay was used to detect the cellular phagocytosis rate of the compounds in A549 cells, and MTT assay was used to detect their dark toxicity and phototoxicity. A nude mouse model of lung cancer was established to investigate the antitumor activity of the compounds mediated photodynamic action in vivo, and the blood concentration of D2 in nude mice, its distribution in tumor tissue and skin tissue were further detected. Results D1 and D2 had strong absorption at 652 nm with the best excitation wavelength at 429 nm and 427 nm, and the optimal emission wavelength was at about 659 nm. They also had a higher singlet oxygen generation rate than the control drug m-THPC. D1 and D2 had no dark toxicity at concentrations below 10 μmol/L, and could be ingested by A549 cells, basically reaching saturation in 18~24 hours. After laser irradiation at 650 nm wavelength, D1 and D2 showed significant antitumor activity in vivo and in vitro （P<0.01）. However, D2 could selectively accumulate in tumor tissues after administration, and the optimal treatment time was less than 30 min after administration. Conclusion D2 had excellent photodynamic antitumor activity and could selectively aggregate in tumor tissues, which had the potential to be a candidate drug for photosensitizer and treatment of lung cancer with independent intellectual property rights, and was worth further research.