1.Effects of Different Stabilization Splint Thicknesses on Stress Distribution in Temporomandibular Joint for Patients with Anterior Disc Displacement with Reduction
Li YAN ; Wei WANG ; Jiaxuan QIU
Journal of Medical Biomechanics 2022;37(2):E280-E286
Objective To compare the stress distributions in temporomandibular joint (TMJ) for patients with bilateral anterior disc displacement with reduction (ADDwR) after wearing stabilization splints with two different thicknesses during prolonged clenching by using three-dimensional (3D) finite element methods. Methods The 3D TMJ finite element models were constructed based on CT and MRI image data when the patient was biting in maximum intercuspation (working condition 1), on 3 mm thickness splint (working condition 2) and on 5 mm thickness splint (working condition 3), respectively. The von Mises stresses in the articular cartilages ,the TMJ disc and bilaminar zone under 3 working conditions were evaluated after the maximum jaw-closing forces were applied to the mandible for 60 s. Results The von Mises stress of left TMJ was bigger than that of right TMJ under each working condition. After wearing the 3 mm thickness splint, the disc was not recaptured, the stress was concentrated at the posterior band and bilaminar zone of the disc, and the stress on bilateral TMJ was significantly increased. After wearing the 5 mm thickness splint, the right disc was recaptured, the maximum stress was located at intermediate zone of the disc, and the von Mises stresses of articular cartilages and bilaminar zone were decreased by about 40%. However, the left disc was not recaptured, and the von Mises stresses of glenoid fossa cartilage and bilaminar zone were only slightly decreased by about 6%. Conclusions Different thicknesses of occlusal splints lead to different stresses and stress distribution patterns in TMJ of patients with ADDwR. The 5 mm thickness stabilization splint can reduce the stress of glenoid fossa cartilage and bilaminar zone in ADDwR patients. Disc recapture is helpful for ADDwR patients to relieve TMJ stress. When using stabilization splints for the treatment of ADDwR patients, on the premise of comfort wearing, a thicker splint can achieve more favorable stress distributions.
2.Exploring the regulatory effects of abdominal breathing training on brain function based on electroencephalogram signals
Ruoshui WANG ; Tianyi LYU ; Xirui ZHAO ; Dan LIN ; Jiaxuan LYU ; Chaoyang ZHANG ; Xinzheng ZHANG ; Kang YAN ; Yulong WEI
Journal of Beijing University of Traditional Chinese Medicine 2024;47(9):1322-1332
Objective To investigate the effects of qigong abdominal breathing training on human brain function.Methods Seventy-two university students were recruited and randomly divided into the control and treatment groups in a 1:1 ratio. Both the control and treatment groups underwent the same standing pile work operation. However,only the treatment group received additional abdominal breathing training. The intervention process comprised two phases:2 weeks of intensive training and 6 weeks of counseling training. Electrocardiogram and electroencephalogram (EEG) tests were performed before (baseline period) and after training respectively. Sample entropy algorithm and empirical mode decomposition were used to analyze the EEG signals. The sample entropy complexity index and the correlation between EEG changes and respiratory curves were calculated to explore the brain function regulation effect. Results The complexity of different brain regions in the treatment group was higher than that of the control group after training. A large difference was observed when comparing the brain complexity in the temporoparietal junction,posterior temporal,parietal,parietal-occipital junction,and occipital regions. The brain complexity in the posterior temporal region of the treatment group was significantly higher than that of the control group after the intervention,with a significant difference (P<0.05). In the control group,the brain complexity in the frontal pole,anterior temporal,frontal reion,frontal-temporal junction,frontal-central junction,middle temporal,central,and temporal-parietal junction regions decreased to different degrees. However,the comparison between before and after was not significant. Furthermore,brain complexity in the central-parietal junction,posterior temporal,parietal,parietal-occipital junction,and occipital regions increased to different degrees in the control group;however,the difference was not significant. The brain complexity of the treatment group in the frontotemporal junction,middle temporal,and temporoparietal junction areas decreased slightly;however,the before-and-after comparison was not significant. The brain complexity of the treatment group in the frontal pole,frontotemporal,frontal,frontal-central junction,central,central-parietal junction,posterior-temporal,parietal,parietal-occipital junction,and occipital areas increased. The posterior-temporal,parietal,parietal-occipital junction,and occipital areas had more significant increases than the other areas. However,the before-and-after comparison was not significant. In both groups,brain complexity decreased in the frontotemporal junction,middle temporal,and temporoparietal junction areas and increased in the parietal,parieto-occipital junction,and occipital areas. The comparison of complexity between the treatment and control groups in P3 and PO3 leads after training was significant. P3 and PO3 are situated in the parietal region and parieto-occipital junction areas,respectively,indicating that antebellum breathing also affects brain function in these regions. The correlation between the respiratory curve and EEG components was enhanced after training. Conclusion Abdominal breathing training can significantly increase the complexity of the corresponding brain regions (posterior temporal,parietal,and parieto-occipital junction regions),and a significant correlation was observed between the two.
3.Reliability of 4D flow cardiac MRI for measuring hemodynamic parameters of left ventricle
Lirong MA ; Jiaxuan GUO ; Wenling LI ; Li MA ; Yan ZHENG ; Huairong ZHANG ; Li ZHU
Chinese Journal of Medical Imaging Technology 2024;40(2):221-225
Objective To observe the reliability of regional 4D flow and whole heart 4D flow cardiac MRI(CMRI)for measuring hemodynamic parameters of left ventricle.Methods Heart ultrasonography and CMRI were prospectively obtained in 31 healthy subjects.Hemodynamic parameters of left ventricle were measured using heart ultrasound,3-chamber 4D flow CMRI(based on inflow and outflow channel of left ventricle)and whole heart 4D flow CMRI,respectively.Intra-class correlation coefficient(ICC)was performed to evaluate the consistencies of the measured left ventricle hemodynamic parameters among the above 3 methods.Results Good consistencies of peak systolic velocity in aortic supravalvular/subvalvular,E peak diastolic velocity of mitral valve,supravalvular/subvalvular aortic pressure and aortic valve pressure gradient(all ICC>0.75),while moderate consistency of A peak diastolic velocity of mitral valve(ICC=0.718)were found between heart ultrasound and 3-chamber 4D flow CMRI.Good consistencies of peak systolic velocity in aortic supravalvular/subvalvular,A peak diastolic velocity of mitral valve and supravalvular/subvalvular aortic pressure(all ICC>0.75),while moderate consistencies of E peak diastolic velocity of mitral valve and aortic valve pressure gradient(ICC=0.600,0.628)were found between heart ultrasound and whole heart 4D flow CMRI.Meanwhile,good consistencies of the above parameters were found between 3-chamber 4D flow CMRI and whole heart 4D flow CMRI(all ICC>0.75).Conclusion Measuring left ventricular hemodynamic parameters using local regional 4D flow and whole heart 4D flow CMRI were reliable,with good consistency with cardiac ultrasound.
4.Effects of icariin-astragaloside IV-puerarin mixture on cognitive function and ferroptosis amino acid metabolism pathway in APP/PS1 HAMP-/-mice
Shan LIU ; Xiaoping HE ; Yan ZHAO ; Jianmin ZHONG ; Yehua ZHANG ; Yiming LIU ; Jiaxuan LI ; Xianhui DONG
Chinese Journal of Pathophysiology 2024;40(3):502-510
AIM:To observe the effect of icariin-astragaloside Ⅳ-puerarin mixture(Yin-Huang-Ge mixture,YHG)on cognitive function and ferroptosis amino acid metabolism pathway in hepcidin(HAMP)knockout APPswe/PS1dE9(APP/PS1 HAMP-/-)mice.METHODS:The mice were divided into 7 groups:negative control(C57BL/6 mice)group,APP/PS1 group,APP/PS1 HAMP-/-group,APP/PS1+YHG group,APP/PS1 HAMP-/-+YHG group,APP/PS1+de-ferasirox(DFX)group,and APP/PS1 HAMP-/-+DFX group,with 6 mice in each group.The YHG and DFX were adminis-tered intragastrically,while the mice in C57 group,APP/PS1 group and APP/PS1 HAMP-/-group were given intragastric administration of distilled water,once a day for 2 months.The iron content in mouse brain tissues was detected by tissue iron kit.The morphological changes of the mitochondria in hippocampal neurons were observed by transmission electron microscopy.Morris water maze was used to detect the learning and memory ability of the mice.The content of neuronal nu-clear antigen(NeuN)in mouse brain tissues was detected by immunofluorescence staining.The expression of glutathione(GSH)in mouse brain tissues was detected by biochemical kit.The expression levels of glutamate-cysteine ligase catalytic subunit(GCLC)and glutamatase 2(GLS2)in mouse brain tissues were detected by Western blot.RESULTS:Compared with C57BL/6 mice,the brain iron content of APP/PS1 mice was significantly increased(P<0.01),the mitochondria were seriously damaged,the learning and memory ability was significantly decreased(P<0.05),the brain neurons were seri-ously damaged(P<0.01),and the expression levels of GSH,GCLC and GLS2 were significantly decreased(P<0.01).Compared with APP/PS1 mice,the brain iron content of APP/PS1 HAMP-/-mice was significantly increased(P<0.01),the mitochondria were seriously damaged,the learning and memory ability was significantly decreased(P<0.05),the brain neurons were seriously damaged(P<0.01),and the expression levels of GSH,GCLC and GLS2 were significantly decreased(P<0.05).After treatment with YHG and DFX,the brain iron content was significantly decreased(P<0.01),the mitochondrial damage was alleviated,the learning and memory ability was significantly increased(P<0.05),the brain neuron damage was alleviated(P<0.01),and the expression levels of GSH,GCLC and GLS2 were significantly increased(P<0.05).CONCLUSION:The YHG can improve the cognitive function of APP/PS1 HAMP-/-mice,and its mechanism may be related to the regulation of ferroptosis amino acid metabolism and the enhancement of antioxidant capacity.
5.Clinical effects comparison of different approaches and anterior attachment release methods in temporomandibular joint disc repositioning and anchoring surgery
WANG Hao ; WANG Wei ; LI Qiang ; YAN Jiaxuan ; NIE Wei ; GUO Yanjun ; YAN Wei ; CHEN Yong
Journal of Prevention and Treatment for Stomatological Diseases 2025;33(2):129-136
Objective:
To explore the therapeutic effects of different surgical methods for temporomandibular joint disc reduction and anchoring surgery, providing reference for optimizing this surgical procedure.
Method:
The study was approved by the hospital ethics committee. 173 patients (195 joints) who underwent temporomandibular joint disc repositioning and anchoring surgery were selected for retrospective analysis. Patients were categorized into groups A (traditional preauricular incision-scalpel/tissue scissors anterior attachment release), 35 patients (40 joints), B (traditional preauricular incision-plasma bipolar radiofrequency electrode anterior attachment release), 42 patients (46 joints), C (revised tragus incision - scalpel/tissue scissors anterior attachment release), 50 patients (58 joints), and D (revised tragus incision-plasma bipolar radiofrequency electrode anterior attachment release), 46 patients (51 joints). After a 6-month postoperative follow-up, the differences in maximum mouth opening (MMO), visual analogue scale (VAS), effective rate of joint disc reduction, incidence of preauricular numbness, obvious scars among patients in each group at 1, 3, and 6 months were compared postoperatively.
Results:
After surgery, the MMO of all four groups of patients initially shrunk and then gradually increased compared to before surgery. At the 1-month follow-up after surgery, the plasma bipolar radiofrequency release (B+D) group had a smaller impact on the patient’s MMO compared to the surgical knife/tissue scissors release (A+C) group (P < 0.05). Postoperative VAS scores for all four groups showed a gradual decrease from pre-operative levels, with the (B+D) group scoring significantly lower in the first month post-surgery compared to the (A+C) group (P < 0.05). Six months post-surgery, the rate of joint disc reduction of the four groups were higher than 95%, with no significant differences observed between the groups (P > 0.05). Patients in the revised tragus incision (C+D) group experienced a lower rate of preauricular numbness compared to those in the traditional preauricular incision (A+B) group (4.59% vs. 12.79%, P < 0.05), The incidence of obvious scars in the (C+D) group was significantly lower than that in the (A+B) group (3.67% vs. 23.26%, P < 0.05).
Conclusion
The revised tragus incision is superior to traditional preauricular incision in terms of protecting the auriculotemporal nerve and the scars were more inconspicuous. Further, the plasma bipolar radiofrequency electrode is superior to the scalpel/tissue scissors in terms of mouth opening recovery and pain control. For temporomandibular joint disc reduction and anchoring surgery, a modified tragus incision combined with plasma bipolar radiofrequency electrode to release the anterior attachment of the joint disc can be recommended as a surgical option.
6.Effects and mechanism of paeoniflorin on oxidative stress of ulcerative colitis mice
Xin DAI ; Ying WANG ; Xinyue REN ; Dingxing FAN ; Xianzhe LI ; Jiaxuan FENG ; Shilei LOU ; Hui YAN ; Cong SUN
China Pharmacy 2025;36(4):427-433
OBJECTIVE To investigate the effects and potential mechanism of paeoniflorin on oxidative stress of ulcerative colitis (UC) mice based on adenosine monophosphate-activated protein kinase (AMPK)/nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway. METHODS Male BALB/c mice were randomly divided into control group, model group, inhibitor group (AMPK inhibitor Compound C 20 mg/kg), paeoniflorin low-, medium- and high-dose groups (paeoniflorin 12.5, 25, 50 mg/kg), high- dose of paeoniflorin+inhibitor group (paeoniflorin 50 mg/kg+Compound C 20 mg/kg), with 8 mice in each group. Except for the control group, mice in all other groups were given 4% dextran sulfate sodium solution for 5 days to establish the UC model. Subsequently, mice in each drug group were given the corresponding drug solution intragastrically or intraperitoneally, once a day, for 7 consecutive days. The changes in body weight of mice were recorded during the experiment. Twenty-four hours after the last administration, colon length, malondialdehyde (MDA) content, and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in colon tissues were measured; histopathological morphology of colon tissues, tight junctions between intestinal epithelial cells, and histopathological scoring were all observed and evaluated; the mRNA expressions of AMPK and Nrf2, as well as the protein expressions of heme oxygenase-1(HO-1), occludin and claudin-1, were all determined in colon tissue. RESULTS Compared with model group, paeoniflorin groups exhibited recovery from pathological changes such as inflammatory cell infiltration and crypt damage in the colon tissue, as well as improved tight junction damage between intestinal epithelial cells. Additionally, significant increases or upregulations were observed in body weight, colon length, activities of SOD and GSH-Px, phosphorylation level of AMPK, and protein expression of Nrf2, HO-1, occludin, claudin-1, and mRNA expressions of AMPK and Nrf2; concurrently, MDA content and histopathological scores were significantly reduced (P< 0.05 or P<0.01). In contrast, the inhibitor group showed comparable (P>0.05) or worse (P<0.05 or P<0.01) indicators compared to the model group. Conversely, the addition of AMPK inhibitor could significantly reverse the improvement of high- dose paconiflorin (P<0.01). CONCLUSIONS Paeoniflorin can repair intestinal epithelial cell damage in mice, improve tight junctions between epithelial cells, upregulate the expression of related proteins, and promote the expression and secretion of antioxidant-promoting molecules, thereby ameliorating UC; its mechanism may be associated with activating AMPK/Nrf2 antioxidant pathway.
7.Single-dose AAV-based vaccine induces a high level of neutralizing antibodies against SARS-CoV-2 in rhesus macaques.
Dali TONG ; Mei ZHANG ; Yunru YANG ; Han XIA ; Haiyang TONG ; Huajun ZHANG ; Weihong ZENG ; Muziying LIU ; Yan WU ; Huan MA ; Xue HU ; Weiyong LIU ; Yuan CAI ; Yanfeng YAO ; Yichuan YAO ; Kunpeng LIU ; Shifang SHAN ; Yajuan LI ; Ge GAO ; Weiwei GUO ; Yun PENG ; Shaohong CHEN ; Juhong RAO ; Jiaxuan ZHAO ; Juan MIN ; Qingjun ZHU ; Yanmin ZHENG ; Lianxin LIU ; Chao SHAN ; Kai ZHONG ; Zilong QIU ; Tengchuan JIN ; Sandra CHIU ; Zhiming YUAN ; Tian XUE
Protein & Cell 2023;14(1):69-73