BACKGROUND:The Twin-block orthodontic appliance is commonly used for the correction of Class Ⅱ malocclusion.Its mechanism of action in stimulating mandibular growth has been confirmed in many studies,but its impact on maxillary growth is not very clear. OBJECTIVE:By establishing a finite element model to analyze the stress distribution of the maxillary complex,surrounding bone sutures,and maxillary dentition in patients with Class Ⅱ malocclusion wearing Twin-block orthodontic appliances. METHODS:One patient with Class Ⅱ malocclusion who underwent orthodontic treatment at Qingdao Hospital/Qingdao Municipal Hospital of Shandong Rehabilitation University was selected.The bite force data of the patient when wearing the Twin-block orthodontic appliance was measured,and CBCT data were collected.A finite element model was established,including the maxillary complex,peripheral sutures,Twin-block orthodontic appliance,and maxillary dentition.ABAQUS software was used to simulate the stress distribution in the maxilla and maxillary dentition when the patient was wearing the Twin-block appliance. RESULTS AND CONCLUSION:The equivalent stress on the maxillary anterior teeth was significantly smaller than that on the posterior teeth,and the maximum equivalent stress on both sides of the teeth were 4.797 5 Mpa and 8.716 1 Mpa,respectively,which were located at the first premolar.The maximum displacements were presented at the maxillary incisors on both sides of the teeth,which were 0.080 5 mm and 0.081 0 mm,respectively.The maximum equivalent stress on the bone suture was 1.284 Mpa,which was mainly concentrated in the pterygopalatine suture and the frontal-maxillary suture on both sides,and there was almost no difference in the force of the rest of bone sutures;the maximum displacement of the bone suture was 0.07 mm,with the pterygopalatine suture having the largest displacement,followed by the frontal-maxillary suture.The maximal equivalent stress on the maxillary complex was 27.18 Mpa,which was mainly concentrated on both sides of the anterior pyriform foramen of the maxilla,around the nasofrontal suture and around the pterygopalatine suture at the posterior part of the jaws.The maximal displacement of the maxilla was 0.07 mm,which was mainly concentrated on the maxillary alveolar bone.All these findings show that the occlusal force acts on the maxillary complex through the Twin-block appliance,resulting in clockwise rotation of the maxilla and steepening of the dentition plane.Measures should be taken to compensate for this tendency,for example,by considering maxillary molar elongation and intrusion in the process of occlusion,which are not only able to flatten the occlusal plane,but facilitate the mandibular protraction,thereby further improving Class Ⅱ malocclusion orthodontic treatment.

ObjectiveThe study explores the influence of voluntary wheel running on the behavioral abnormalities and the activation state of the hypothalamic-pituitary-adrenal (HPA) axis in autism spectrum disorder (ASD) rats through gut microbiota. MethodsSD female rats were selected and administered either400 mg/kg of valproic acid (VPA) solution or an equivalent volume of saline via intraperitoneal injection on day 12.5 of pregnancy. The resulting offspring were divided into 2 groups: the ASD model group (PASD, n=35) and the normal control group (PCON, n=16). Behavioral assessments, including the three-chamber social test, open field test, and Morris water maze, were conducted on postnatal day 23. After behavioral testing, 8 rats from each group (PCON, PASD) were randomly selected for serum analysis using enzyme-linked immunosorbent assay (ELISA) to measure corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT) concentration, to evaluate the functional state of the HPA axis in rats. On postnatal day 28, the remaining 8 rats in the PCON group were designated as the control group (CON, n=8), and the remaining 27 rats in the PASD group were randomly divided into 4 groups: ASD non-intervention group (ASD, n=6), ASD exercise group (ASDE, n=8), ASD fecal microbiota transplantation group (FMT, n=8), and ASD sham fecal microbiota transplantation group (sFMT, n=5). The rats in the ASD group and the CON group were kept under standard conditions, while the rats in the ASDE group performed 6 weeks of voluntary wheel running intervention starting on postnatal day 28. The rats in the FMT group were gavaged daily from postnatal day 42 with 1 ml/100 g fresh fecal suspension from ASDE rats which had undergone exercise for 2 weeks, 5 d per week, continuing for 4 weeks. The sFMT group received an equivalent volume of saline. After the interventions were completed, behavioral assessments and HPA axis markers were measured for all groups. ResultsBefore the intervention, the ASD model group exhibited significantly reduced social ability, social novelty preference, spontaneous activity, and exploratory interest, as well as impaired spatial learning, memory, and navigation abilities compared to the normal control group (P<0.05). Serum concentration of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT) in the PASD group were significantly higher than those in the PCON group (P<0.05). Following 6 weeks of voluntary wheel running, the ASDE group showed significant improvements in social ability, social novelty preference, spontaneous activity, exploratory interest, spatial learning, memory, and navigation skills compared to the ASD group (P<0.05), with a significant decrease in serum CORT concentration (P<0.05), and a downward trend in CRH and ACTH concentration. After 4 weeks of fecal microbiota transplantation in the exercise group, the FMT group showed marked improvements in social ability, social novelty preference, spontaneous activity, exploratory interest, as well as spatial learning, memory, and navigation abilities compared to both the ASD and sFMT groups (P<0.05). In addition, serum ACTH and CORT concentration were significantly reduced (P<0.05), and CRH concentration also showed a decreasing trend. ConclusionExercise may improve ASD-related behaviors by suppressing the activation of the HPA axis, with the gut microbiota likely playing a crucial role in this process.

As China accelerates its efforts in deep space exploration and long-duration space missions, including the operationalization of the Tiangong Space Station and the development of manned lunar missions, safeguarding astronauts’ physiological and cognitive functions under extreme space conditions becomes a pressing scientific imperative. Among the multifactorial stressors of spaceflight, microgravity emerges as a particularly potent disruptor of neurobehavioral homeostasis. Dopamine (DA) plays a central role in regulating behavior under space microgravity by influencing reward processing, motivation, executive function and sensorimotor integration. Changes in gravity disrupt dopaminergic signaling at multiple levels, leading to impairments in motor coordination, cognitive flexibility, and emotional stability. Microgravity exposure induces a cascade of neurobiological changes that challenge dopaminergic stability at multiple levels: from the transcriptional regulation of DA synthesis enzymes and the excitability of DA neurons, to receptor distribution dynamics and the efficiency of downstream signaling pathways. These changes involve downregulation of tyrosine hydroxylase in the substantia nigra, reduced phosphorylation of DA receptors, and alterations in vesicular monoamine transporter expression, all of which compromise synaptic DA availability. Experimental findings from space analog studies and simulated microgravity models suggest that gravitational unloading alters striatal and mesocorticolimbic DA circuitry, resulting in diminished motor coordination, impaired vestibular compensation, and decreased cognitive flexibility. These alterations not only compromise astronauts’ operational performance but also elevate the risk of mood disturbances and motivational deficits during prolonged missions. The review systematically synthesizes current findings across multiple domains: molecular neurobiology, behavioral neuroscience, and gravitational physiology. It highlights that maintaining DA homeostasis is pivotal in preserving neuroplasticity, particularly within brain regions critical to adaptation, such as the basal ganglia, prefrontal cortex, and cerebellum. The paper also discusses the dual-edged nature of DA plasticity: while adaptive remodeling of synapses and receptor sensitivity can serve as compensatory mechanisms under stress, chronic dopaminergic imbalance may lead to maladaptive outcomes, such as cognitive rigidity and motor dysregulation. Furthermore, we propose a conceptual framework that integrates homeostatic neuroregulation with the demands of space environmental adaptation. By drawing from interdisciplinary research, the review underscores the potential of multiple intervention strategies including pharmacological treatment, nutritional support, neural stimulation techniques, and most importantly, structured physical exercise. Recent rodent studies demonstrate that treadmill exercise upregulates DA transporter expression in the dorsal striatum, enhances tyrosine hydroxylase activity, and increases DA release during cognitive tasks, indicating both protective and restorative effects on dopaminergic networks. Thus, exercise is highlighted as a key approach because of its sustained effects on DA production, receptor function, and brain plasticity, making it a strong candidate for developing effective measures to support astronauts in maintaining cognitive and emotional stability during space missions. In conclusion, the paper not only underscores the centrality of DA homeostasis in space neuroscience but also reflects the authors’ broader academic viewpoint: understanding the neurochemical substrates of behavior under microgravity is fundamental to both space health and terrestrial neuroscience. By bridging basic neurobiology with applied space medicine, this work contributes to the emerging field of gravitational neurobiology and provides a foundation for future research into individualized performance optimization in extreme environments.

Humans ; Adolescent ; Acne Vulgaris/therapy* ; Skin Care ; Surveys and Questionnaires ; Cognition ; China ; Skin

Aim To investigate the role of metabolites of eicosapentaenoic acid (EPA) in promoting the transdifferentiation of pancreatic α cells to β cells. Methods Male C57BL/6J mice were injected intraperitoneally with 60 mg/kg streptozocin (STZ) for five consecutive days to establish a type 1 diabetes (T1DM) mouse model. After two weeks, they were randomly divided into model groups and 97% EPA diet intervention group, 75% fish oil (50% EPA +25% DHA) diet intervention group, and random blood glucose was detected every week; after the model expired, the regeneration of pancreatic β cells in mouse pancreas was observed by immunofluorescence staining. The islets of mice (obtained by crossing GCG

Twelve compounds were isolated from the ethyl acetate fraction of the 80% aqueous ethanol extract of the roots and stems of Dalbergia rimosa Roxb. by silica gel, MCI, Sephadex LH-20 column chromatography, and semi-preparative HPLC. Their structures were identified by spectral analysis such as UV, IR, MS, 1D/2D NMR and by comparison with literature information as dalbergiquinol A (1), dalbergiquinol B (2), R-(-)-3′-hydroxy-2,4,5-trimethoxydalbergiquinol (3), neokhriol A (4), mucronulatol (5), (3R)-7,2′,3′-trihydroxy-4′-methoxy-isoflavane (6), isomucronulatol (7), (3S)-violanone (8), 3′-O-methylviolanone (9), eryvarin M (10), (±)-α,3,4,2′,4′-pentahydroxydihydrochalcone (11) and (-)-butin (12). Compound 1 and 2 are new compounds, and compounds 3-12 were isolated from this plant for the first time. Compounds 1, 2, 4, 6, 8, 11, 12 showed good scavenging effect on DPPH free radical.

Objective To explore the severity of loneliness among the elderly in communities in Shanghai,and to identify factors associated with social and emotional loneliness respectively.Methods A cross-sectional study was conducted in older adults aged 65 years or above in Pudong New Area,Jing'an District and Huangpu District in Shanghai from Mar to Jun 2021.In Pudong New Area,multi-stage stratified random sampling was conducted based on the age and gender distribution of Shanghai,while in Huangpu District and Jing'an District convenience sampling was conducted.A total of 635 samples were included in the study.Loneliness was assessed using the De Jong Gierveld Loneliness Scale with social and emotional loneliness subscales.Logistic regression analyses were conducted to identify factors associated with social and emotional loneliness.Results Among the 635 participants,only 53 older adults(8.4%)were not lonely.Female(OR=0.46,95%CI:0.31-0.70),higher self-efficacy(OR=0.97,95%CI:0.94-1.00),more objective social support(OR=0.96,95%CI:0.93-0.99)were associated with less severe social loneliness.Meanwhile,higher level of education(secondary education,OR=0.56,95%CI:0.34-0.95;college or above,OR=0.30,95%CI:0.11-0.83)and higher self-efficacy(OR=0.96,95%CI:0.93-0.99)were associated with less severe emotional loneliness,while depression(OR=3.41,95%CI:1.76-6.60)and worse social capital(OR=2.02,95%CI:1.29-3.16)were associated with more severe emotional loneliness.Conclusion Up to 91.6%of the elderly in our study sample were moderately lonely or above.The factors associated with social loneliness include self-efficacy,gender and social support.The factors associated with emotional loneliness are self-efficacy,education level,depression,and social capital.

Objective To explore the relationship and internal path between activities of daily living(ADL),sleep quality and mental health of community elderly people in Shanghai.Methods A questionnaire survey was conducted among community residents aged 60 years and older seeing doctors in community health care center of five streets in Shanghai during Sept to Dec,2021 using convenience sampling.Activities of Daily Living(ADL),Pittsburgh Sleep Quality Index(PSQI)and 10-item Kessler Psychological Distress Scale(K10)were adopted in the survey.Single factor analysis,correlation analysis and multiple linear regression were used to analyze the data.The effect relationship between the variables was tested using Bootstrap's mediated effects test.Results A total of 1 864 participants were included in the study.The average score was 15.53±4.47 for ADL,5.60±3.71 for PSQI and 15.50±6.28 for K10.The rate of ADL impairment,poor sleep quality,poor and very poor mental health of the elderly were 23.6%,27.3%,11.9%and 4.9%,respectively.ADL and sleep quality were all positively correlated with mental health(r=0.321,P＜0.001;r=0.466,P＜0.001);ADL was positively correlated with sleep quality(r=0.294,P＜0.001).Multiple linear results of factors influencing mental health showed that ADL(β= 0.457,95%CI:0.341-0.573),sleep quality(β =0.667,95%CI:0.598-0.737)and mental health were positively correlated(P＜0.001).Sleep quality partially mediated the relationship between ADL and mental health(95%CI:0.078-0.124)with an effect size of 33.0%.Conclusion Sleep quality is a mediator between ADL and mental health among community elderly people.Improving ADL and sleep quality may improve mental health in the population.

BACKGROUND:The treatment of distal tibial comminuted fractures with soft tissue injury has always been challenging.The new retrograde tibial nailing and supercutaneous locking plate are important treatment methods,but their strain and stress shielding at the fracture end during different periods of fracture healing and different load conditions have not been reported. OBJECTIVE:To explore the biomechanical stability of retrograde tibial nailing and supercutaneous locking plate in different periods of fracture healing by finite element analysis to offer a scientific foundation for clinical application and rehabilitation exercise. METHODS:The finite element model of distal tibial comminuted fracture was established by utilizing the CT data of the tibia from a 40-year-old healthy male.Retrograde tibial nailing,supercutaneous locking plate,and callus models were assembled in accordance with the principle of fracture fixation.The finite element analysis was performed using ANSYS software to compare the displacement of the fracture end,the stress shielding of the tibia,the stress of the callus,and the stress distribution of the tibia and the fixation device during different periods of fracture healing. RESULTS AND CONCLUSION:(1)The relative displacement of the tibial fracture decreased gradually with the healing of the fracture,and the displacement decreased significantly after 3 months.At 0 and 1 months after operation,the vertical displacement and total displacement of the supercutaneous locking plate group were higher than those in the retrograde intramedullary nail group.The Z-axis displacement(horizontal medial and lateral displacement)of the two fixation methods was more obvious than the X-axis and Y-axis,and the Z-axis displacement of supercutaneous locking plate group was the most obvious.The maximum Z-axis displacement of the two fixation methods was located on the outside of the tibia,and the minimum displacement was located on the inside of the tibia.(2)The stress shielding rate at different periods of fracture healing gradually decreased with time.The stress shielding rate of the retrograde intramedullary nail was higher than that of the supercutaneous locking plate at different stages of fracture healing.After 3 months,the stress shielding rate of the supercutaneous locking plate was reduced to about 4%,and the stress shielding rate of the retrograde intramedullary nail was reduced to about 40%.(3)The stress of the stress concentration site of the callus in the two fixation methods increased with the increase of the load,and the stress of the callus in the supercutaneous locking plate group was always greater than that in the retrograde intramedullary nail group.The maximum stress distribution of the callus was approximately equally distributed among the two modes of fixation,both in the lateral portion of the tibia.(4)As the fracture healed,the maximum stress of the tibia in the two groups decreased gradually,and the stress in the supercutaneous locking plate group was always greater than that in the retrograde intramedullary nail group.The average stress of the maximum stress area of the tibia in the supercutaneous locking plate group under 1 500 N load was 285 MPa,while that in the retrograde intramedullary nail group was 26 MPa.(5)As the fracture healed,the stress of the fixation device in the two groups decreased gradually,and the stress in the supercutaneous locking plate group was significantly higher than that in the retrograde intramedullary nail group.After 3 months,the stress of the two fixation devices decreased significantly.(6)It is indicated that in the early stage of fracture healing,the strain on the fracture end in the retrograde intramedullary nail group is small,and the maximum stress of the tibia is moderate,allowing early loaded.The fractured ends in the supercutaneous locking plate group had too large strain and too large maximum stress of the tibia,which needed to be partially loaded under protection and could not be fully loaded.In the middle and late stages of fracture healing,the tibial retrograde intramedullary nail and the supercutaneous locking plate could be completely loaded,and the stress shielding rate of the supercutaneous locking plate was significantly lower than the tibial retrograde intramedullary nail.

BACKGROUND:The displacement change parameters of the bone structure of the first metatarsal bone at the two-dimensional level of hallux valgus deformity are of great significance for clinical diagnosis and treatment,while the quantitative analysis of the three-dimensional deformity index may have some influences on the postoperative efficacy. OBJECTIVE:To explore the quantitative change of the three-dimensional deformity index of the first metatarsal bone after routine osteotomy and orthosis for hallux valgus deformity and to provide reference for clinical work. METHODS:100 patients with hallux valgus deformity(foot)in Hengshui People's Hospital from October 2020 to April 2023 were selected and all of them underwent conventional osteotomy and orthosis.Foot function was assessed by the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale 6 months after surgery.Anterolateral X-rays of the foot in weight-bearing position and CT images in simulated weight-bearing position were taken before surgery and 6 months after surgery.The three-dimensional deformity indexes of the first metatarsal bone before and after surgery were quantitatively analyzed in patients with different ages,genders and therapeutic effects,including first-second intermetatarsal angle,hallux valgus angle,distal metatarsal articular angle,tibial sesamaid position,and first metatarsal rotation α angle.The value of the difference of three-dimensional deformity indexes of the first metatarsal bone before and after operation in evaluating the curative effect was analyzed. RESULTS AND CONCLUSION:(1)Six months after operation,the American Orthopedic Foot and Ankle Society score was 75-98(88.25±4.14)points,among which 56 cases were excellent,28 cases were good,14 cases were average,and 2 cases were poor.The excellent and good rate was 84%(84/100).(2)Compared with the preoperative results,first-second intermetatarsal angle,hallux valgus angle,distal metatarsal articular angle,tibial sesamaid position,and first metatarsal rotation α angle were significantly improved in patients of different ages and genders 6 months after surgery(P<0.05).First-second intermetatarsal angle,hallux valgus angle,distal metatarsal articular angle,tibial sesamaid position,and first metatarsal rotation α angle were all lower in patients with good curative effect 6 months after surgery than those with poor curative effect,and the difference before and after surgery was greater than those with poor curative effect(P<0.05).(3)The area under the curve of the difference evaluation of the first metatarsal three-dimensional deformity index before and after surgery was above 0.7,and the area under the curve of the combined evaluation of all indexes was the largest(0.902),which was significantly greater than the first metatarsal rotation α angle and distal metatarsal articular angle(P<0.05).(4)The quantitative analysis of the three-dimensional deformity index of the first metatarsal in patients with hallux valgus deformity is related to the postoperative effect,which has important guiding significance for improving the accuracy and comprehensiveness of preoperative evaluation and improving the treatment plan.