1.Osteogenic ability and autophagy level between normal and inflammatory periodontal ligament stem cells
Jiaqi MAO ; Liru ZHAO ; Dongru YANG ; Yongqing HU ; Bowen DAI ; Shujuan LI
Chinese Journal of Tissue Engineering Research 2025;29(1):74-79
BACKGROUND:Inflammation affects the osteogenic differentiation of periodontal ligament stem cells,and the osteogenic ability and autophagy level of periodontal ligament stem cells are closely related.However,there are no relevant reports on whether inflammation affects the osteogenic ability and autophagy level of periodontal ligament stem cells at different stages of osteogenic differentiation. OBJECTIVE:To explore alkaline phosphatase expression and autophagy periodontal ligament stem cells levels in periodontitis and normal conditions. METHODS:Periodontal ligament stem cells from normal and periodontitis patients were isolated and cultured,and underwent Vimentin,pan-CK,and Stro-1 fluorescence staining.At 3,7,and 14 days of osteogenic differentiation,western blot assay was used to detect the protein expression levels of alkaline phosphatase,LC3B,Beclin1,and ATG5 in normal and inflammatory periodontal ligament stem cells.The mRNA expression levels of alkaline phosphatase,bone sialoprotein,osteocalcin,Runx2,LC3B,Beclin1,and ATG5 were detected by real-time PCR. RESULTS AND CONCLUSION:(1)Stro-1 was positive,Vimentin was positive,and pan CK was negative in periodontal ligament stem cells.(2)At 3,7,and 14 days after osteogenic differentiation,compared with normal periodontal ligament stem cells,the mineralization nodules formed by periodontal ligament stem cells from inflammatory sources were significantly reduced(P<0.01);the expression of alkaline phosphatase protein and mRNA was significantly lower(P<0.05);the mRNA expression levels of bone sialoprotein,osteocalcin,and Runx2 were significantly decreased(P<0.05).(3)At 7 and 14 days after osteogenic differentiation,compared with normal periodontal ligament stem cells,the expression levels of ATG5,LC3B,and Beclin1 proteins and mRNA of periodontal ligament stem cells were downregulated(P<0.05).These findings suggest that inflammation reduces the activity of periodontal ligament stem cells in mineralizing nodule formation and the expression of alkaline phosphatase and weakens the autophagy potential of periodontal ligament stem cells at 7 and 14 days after osteogenic differentiation.
2.Gushukang interferes with osteoclasts:activation of nuclear factor erythroid 2-related factor 2 regulates the c-Fos/NFATc1 pathway in the treatment of osteoporosis
Chengzhi HOU ; Jiatong HAN ; Guangcheng WEI ; Zechuan ZHUO ; Qiuyue LI ; Yong ZHAO ; Zhangjingze YU
Chinese Journal of Tissue Engineering Research 2025;29(2):279-285
BACKGROUND:It has been shown that Gushukang affects bone metabolism by regulating nucleotide and amino acid metabolism and immune mechanisms.Current research on the mechanism of Gushukang in the treatment of osteoporosis primarily focuses on osteoblast regulation and requires further improvement from the perspective of osteoclasts. OBJECTIVE:To investigate the mechanism by which Gushukang interferes with osteoclasts in the treatment of osteoporosis using RAW264.7 cells as the research model. METHODS:Twenty-four 8-week-old female Sprague-Dawley rats were randomly divided into four groups(n=6 per group):the three experimental groups were given 1,2 and 4 g/kg osteoporosis solution by gavage(2 times per day),and the control group was given an equal amount of distilled water by gavage(2 times per day).After 7 days of intragastric administration,aortic blood samples were extracted to collect serum samples using centrifugation,and serum samples from the same groups were combined to obtain the low-,medium-,and high-concentration Gushukang-containing and normal sera for the subsequent experiments.(1)RAW264.7 cells were cultured in six groups:normal serum was added to the control group;low,medium,and high concentration groups were added with low,medium,and high concentrations of Gushukang-containing serum,respectively;ML385,a nuclear factor erythroid 2-related factor 2(Nrf2)inhibitor was given in the Nrf2 inhibitor group;and t-BHQ,a Nrf2 activator,was added in the Nrf2 activator group.Cell viability was detected using the cell counting kit-8 assay.(2)The 3rd generation RAW 264.7 cells were cultured and divided into five groups:the blank control group was added with normal serum,the osteoclast group was added with receptor activator of nuclear factor κB ligand(RANKL),and the low-,medium-,and high-concentration groups were added with low-,medium-,and high-concentration Gushukang-containing serum based on the addition of RANKL.Tartrate-resistant acid phosphate staining was performed after 5 days of culture.(3)RAW264.7 cells were cultured and divided into five groups:blank control group was cultured with normal serum,osteoclast group cultured with normal serum and RANKL,high concentration+osteoclast group cultured with RANKL+high concentration Gushukang-containing serum,osteoclast+Nrf2 agonist group cultured with RANKL+t-BHQ,and high concentration+osteoclast+Nrf2 inhibitor group cultured with RANKL+high concentration Gushukang-containing serum+ML385.Western blot assay and determination of reactive oxygen content were performed after 5 days of culture. RESULTS AND CONCLUSION:The cell counting kit-8 results indicated that Gushukang-containing serum,NRF2 inhibitor or agonist had no significant effect on RAW264.7 cell viability.Tartrate-resistant acid phosphate staining results demonstrated that Gushukang-containing serum exhibited a concentration-dependent inhibitory effect on osteoclast differentiation.Western blot analysis and determination of reactive oxygen species revealed that compared with the blank control group,Nrf2 protein expression was decreased in the osteoclast group(P<0.05),while c-Fos and NFATc1 protein expression and reactive oxygen species content were elevated(P<0.05);compared with the osteoclast group,Nrf2 protein expression was elevated and reactive oxygen species content was decreased in the high-concentration+osteoclast group,osteoclast+Nrf2 agonist group,and high-concentration+osteoclast+Nrf2 inhibitor group(P<0.05),while c-Fos and NFATc1 protein expression was decreased in the high concentration+osteoclast group and osteoclast+Nrf2 agonist group(P<0.05);compared with the high concentration+osteoclast group,Nrf2 protein expression was decreased(P<0.05)and reactive oxygen species content was elevated(P<0.05)in the high concentration+osteoclast+Nrf2 inhibitor group.To conclude,Gushukang reduces reactive oxygen species production by activating Nrf2,thereby inhibiting downstream of the c-Fos/NFATc1 pathway and suppressing osteoclast differentiation.
3.Jiawei Chunze Decoction treats urinary retention after spinal cord injury in rats based on the regulation of endoplasmic reticulum stress apoptosis
Bochao ZHU ; Yanjie LI ; Hewei QIN ; Nannan ZHAO ; Haoyuan LIU ; Zhenhua XU ; Yupu WANG
Chinese Journal of Tissue Engineering Research 2025;29(2):371-378
BACKGROUND:Preliminary clinical observations found that Jiawei Chunze Decoction is an effective formula for clinical treatment of urinary retention after spinal cord injury.Animal experiments have found that the phosphatidylinositol 3-kinase/protein kinase B(PI3K/Akt)signaling pathway is closely related to the degree of bladder dysfunction. OBJECTIVE:To further investigate the effects of Jiawei Chunze Decoction on bladder function and PI3K/Akt signaling pathway in rats with urinary retention. METHODS:Sixty female Sprague-Dawley rats were randomly divided into sham operation group,model group,Jiawei Chunze Decoction low-dose group,Jiawei Chunze Decoction high-dose group and agonist group.In the sham operation group,the spinal cord was exposed but not transected.In the other groups,the modified Hassan Shaker spinal cord transection method was used to prepare the model of sacral medullary injury.At 24 hours after modeling,the sham operation group and model group were intragastrically given equal volume of normal saline,Jiawei Chunze Decoction low-dose and high-dose groups were given Jiawei Chunze Decoction granules containing 14.4 and 28.8 g/kg,respectively,via intragastric administration for 4 weeks,and the agonist group was treated with an intraperitoneal injection of PI3K/Akt signaling pathway agonist 740Y-P at a dose of 0.02 mg/kg.After 4 weeks of treatment,the maximum bladder capacity,leakage point pressure and bladder compliance of rats in each group were detected by urine flow dynamics.The minimum bladder contraction tension and frequency of rats in each group were detected by detrusor pull test.The pathological changes of the rat bladder in each group were observed by hematoxylin-eosin staining.The concentrations of GRP78,CHOP and Caspase-12 in serum were detected by ELISA,and the mRNA and protein expressions of PI3K,Akt,GRP78,CHOP and Caspase-12 in bladder tissues were detected by RT-PCR and western blot,respectively. RESULTS AND CONCLUSION:Compared with the sham operation group,the maximum bladder volume,bladder compliance and minimum systolic tension of rats in the model group were increased(P<0.05),and the leakage point pressure and bladder contraction frequency were decreased(P<0.05);serum GRP78,CHOP,and Caspase-12 levels were also increased(P<0.05).The arrangement of bladder epithelial cells in the model group was disordered,and there was monocyte infiltration between cells,tissue edema,and detrusor tract atrophy.The mRNA and protein expressions of PI3K and Akt in bladder tissues were significantly decreased in the model group compared with the sham operation group,while those of GRP78,CHOP and Caspase-12 were increased(P<0.05).Compared with the model group,the maximum bladder volume,bladder compliance and minimum systolic tension of rats were decreased in the Jiawei Chunze Decoction low-dose,high-dose and agonist groups after 4 weeks of intervention(P<0.05),while the leakage point pressure and bladder contraction frequency were increased(P<0.05);serum GRP78,CHOP,Caspase-12 levels were decreased(P<0.05).The bladder epithelial cells in the three intervention groups were distributed evenly,arranged neatly,with less inflammatory cell infiltration and fuller detrusor muscle bundle.Compared with the model group,the mRNA and protein expressions of PI3K and Akt were increased in the three intervention groups,while those of GRP78,CHOP and Caspase-12 were decreased(P<0.05).The Jiawei Chunze Decoction high-dose group was better than the Jiawei Chunze Decoction low-dose group and shared the similar results with the agonist group.To conclude,Jiawei Chunze Decoction can improve the bladder function of rats with urinary retention after spinal cord injury,and the mechanism may be related to reducing the occurrence of endoplasmic reticulum stress in bladder tissue through the PI3K/Akt signaling pathway,and then alleviating apoptosis.
4.Establishment and stress analysis of a finite element model for adolescent cervical disc herniation
Yuxin ZHAO ; Liang LIANG ; Feng JIN ; Yangyang XU ; Zhijie KANG ; Yuan FANG ; Yujie HE ; Xing WANG ; Haiyan WANG ; Xiaohe LI
Chinese Journal of Tissue Engineering Research 2025;29(3):448-454
BACKGROUND:Cervical disc herniation can cause pain in the neck and shoulder area,as well as radiating pain in the upper limbs.The incidence rate is increasing year by year and tends to affect younger individuals.Fully understanding the biomechanical characteristics of the cervical spine in adolescents is of great significance for preventing and delaying the onset of cervical disc herniation in this age group. OBJECTIVE:To reconstruct cervical spine models for both healthy adolescents and adolescent patients with cervical disc herniation utilizing finite element analysis techniques,to analyze the motion range of the C1-T1 cervical vertebrae as well as the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and the cartilage of the small joints. METHODS:A normal adolescent's cervical spine and an adolescent patient with cervical disc herniation were selected in this study.The continuous scan cervical spine CT raw image data were imported into Mimics 21.0 in DICOM format.The C1-T1 vertebrae were reconstructed separately.Subsequently,the established models were imported into the 3-Matic software for disc reconstruction.The perfected models were then imported into Hypermesh software for meshing of the vertebrae,nucleus pulposus,annulus fibrosus,and ligaments,creating valid geometric models.After assigning material properties,the final models were imported into ABAQUS software to observe the joint motion range of the C1-C7 cervical vertebrae segments under different conditions,and to analyze the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and small joint cartilage of each cervical spine segment. RESULTS AND CONCLUSION:(1)In six different conditions,the joint motion range of the C1 vertebra in the cervical spine models of both normal adolescent and adolescent patient with cervical disc herniation was higher than that of the other vertebrae.Additionally,the joint motion range of each cervical spine segment in normal adolescent was greater than that in adolescent patient with cervical disc herniation.(2)In the cervical spine model of normal adolescent,the maximum stress values in the annulus fibrosus and nucleus pulposus were found on the left side during C2-3 flexion conditions(0.43 MPa and 0.17 MPa,respectively).In the cervical spine model of adolescent patient with cervical disc herniation,the maximum stress values were found on the left side during C7-T1 flexion conditions(0.54 MPa and 0.18 MPa,respectively).(3)In the cervical spine model of normal adolescent,the maximum stress value on the endplate was found on the left side of the upper endplate of C3 during flexion conditions(1.46 MPa).In the model of adolescent patient with cervical disc herniation,the maximum stress value on the endplate was found on the left side of the lower endplate of C7 during flexion conditions(1.32 MPa).(4)In the cervical spine model of normal adolescent,the maximum stress value in the small joint cartilage was found in the C2-3 left rotation conditions(0.98 MPa).In adolescent patient with cervical disc herniation,the stress in the small joint cartilage significantly increased under different conditions,especially in C1-2,with the maximum stress found during left flexion(3.50 MPa).(5)It is concluded that compared to normal adolescent,adolescent patient with cervical disc herniation exhibits altered cervical curvature and a decrease in overall joint motion range in the cervical spine.In adolescent with cervical disc herniation,there is a significant increase in stress on the annulus fibrosus,nucleus pulposus,and endplates in the C7-T1 segment.The stress on the left articular cartilage of the C1-2 is notable.Abnormal cervical curvature may be the primary factor causing these stress changes.
5.Anti-inflammatory and osteogenic effects of chitosan/sodium glycerophosphate/sodium alginate/leonurine hydrogel
Zengbo ZHAO ; Chenxi LI ; Chenlei DOU ; Na MA ; Guanjun ZHOU
Chinese Journal of Tissue Engineering Research 2025;29(4):678-685
BACKGROUND:Leonurine has many biological activities such as improving microcirculation,anti-oxidation,anti-apoptosis,scavenging free radicals,anti-inflammation,and anti-fibrosis,and can promote osteogenic differentiation of bone marrow mesenchymal stem cells,which has the potential to be applied in the treatment of periodontitis. OBJECTIVE:To explore the anti-inflammatory and osteogenic effects of leonurine loading into chitosan/sodium glycerophosphate/sodium alginate hydrogel. METHODS:(1)Chitosan/sodium glycerophosphate/sodium alginate hydrogel(blank hydrogel)and chitosan/sodium glycerophosphate/sodium alginate/leonurus alkali hydrogel were prepared respectively.RAW 264.7 and MC3T3-E1 cells were inoculated with the two kinds of hydrogel.The cytotoxicity of hydrogels was detected by CCK-8 assay and live/dead cell staining.(2)RAW 264.7 cells were cultured in five groups.The blank group was cultured for 24 hours routinely.The lipopolysaccharide group was treated with lipopolysaccharide.The simple hydrogel group was treated with lipopolysaccharide and blank hydrogel.The drug-loaded hydrogel group was treated with lipopolysaccharide and drug-loaded hydrogel.The inhibitor group was treated with lippolysaccharide,drug-loaded hydrogel,and PI3K inhibitor LY294002.24 hours later,mRNA expression of inflammation-related factors was detected by qRT-PCR.Western blot assay was utilized to detect the protein expression of inflammation-related factors and PI3K/AKT signaling pathway.(3)MC3T3-E1 cells were inoculated in four groups.The blank group was cultured without any material.The simple hydrogel group was treated with blank hydrogel.The drug-loaded hydrogel group was treated with drug-loaded hydrogel.The inhibitor group was treated with drug-loaded hydrogel and PI3K inhibitor LY294002 for 7 days.Alkaline phosphatase staining was performed.mRNA expression levels of osteogenic factors were detected by qRT-PCR.The protein expression levels of the PI3K/AKT signaling pathway were detected by western blot assay. RESULTS AND CONCLUSION:(1)The results of CCK-8 assay and live/dead cell staining showed that the two kinds of hydrogels had no cytotoxic effect and had good cytocompatibility.(2)Compared with the blank group,the mRNA and protein expression levels of interleukin 6,tumor necrosis factor α,and interleukin 1β were significantly increased(P<0.05),and the protein expression levels of p-AKT,p-PI3K,p-p65,and p-IκBα were significantly increased in the lipopolysaccharide group(P<0.05).Compared with lipopolysaccharide group,mRNA and protein expression levels of the above indexes were decreased in drug-loaded hydrogel group(P<0.05).Compared with the drug-loaded hydrogel group,the mRNA and protein expression levels of the above indexes were decreased in the inhibitor group(P<0.05).(3)The activity of alkaline phosphatase in drug-loaded hydrogel group was higher than that in the blank group,simple hydrogel group,and inhibitor group(P<0.05).Compared with blank group,the mRNA expression levels of alkaline phosphatase,Runx2,osteocalcin,and type I collagen were increased(P<0.05),and the protein expression levels of p-AKT and p-PI3K were increased in the simple hydrogel group(P<0.05).Compared with the simple hydrogel group,the mRNA and protein expression levels of the above indexes were increased in the drug-loaded hydrogel group(P<0.05).Compared with the drug-loaded hydrogel group,the mRNA and protein expression levels of the above indexes were decreased in the inhibitor group(P<0.05).(4)These findings conclude that chitosan/sodium glycerophosphate/sodium alginate/leonurine hydrogel has anti-inflammatory and osteogenic effects,which may be related to the regulation of PI3K/AKT signaling pathway.
6.Internal tension relieving technique assisted anterior cruciate ligament reconstruction to promote ligamentization of Achilles tendon grafts in small ear pigs in southern Yunnan province
Bohan XIONG ; Guoliang WANG ; Yang YU ; Wenqiang XUE ; Hong YU ; Jinrui LIU ; Zhaohui RUAN ; Yajuan LI ; Haolong LIU ; Kaiyan DONG ; Dan LONG ; Zhao CHEN
Chinese Journal of Tissue Engineering Research 2025;29(4):713-720
BACKGROUND:We have successfully established an animal model of small ear pig in southern Yunnan province with internal tension relieving technique combined with autologous Achilles tendon for anterior cruciate ligament reconstruction,and verified the stability and reliability of the model.However,whether internal tension relieving technique can promote the ligamentalization process of autologous Achilles tendon graft has not been studied. OBJECTIVE:To investigate the differences in the process of ligamentalization between conventional reconstruction and internal reduction reconstruction of the anterior cruciate ligament by gross view,histology and electron microscopy. METHODS:Thirty adult female small ear pigs in southern Yunnan province were selected.Anterior cruciate ligament reconstruction was performed on the left knee joint with the ipsilateral knee Achilles tendon(n=30 in the normal group),and anterior cruciate ligament reconstruction was performed on the right knee joint with the ipsilateral knee Achilles tendon combined with the internal relaxation and enhancement system(n=30 in the relaxation group).The autogenous right forelimb was used as the control group;the anterior cruciate ligament was exposed but not severed or surgically treated.At 12,24,and 48 weeks after surgery,10 animals were sacrificed,respectively.The left and right knee joint specimens were taken for gross morphological observation to evaluate the graft morphology.MAS score was used to evaluate the excellent and good rate of the ligament at each time point.Hematoxylin-eosin staining was used to evaluate the degree of ligament graft vascularization.Collagen fibers and nuclear morphology were observed,and nuclear morphology was scored.Ultrastructural remodeling was evaluated by scanning electron microscopy and transmission electron microscopy. RESULTS AND CONCLUSION:(1)The ligament healing shape of the relaxation group was better at various time points after surgery,and the excellent and good rate of MAS score was higher(P<0.05).Moreover,the relaxation group could obtain higher ligament vascularization score(P<0.05).(2)The arrangement of collagen bundles and fiber bundles in the two groups gradually tended to be orderly,and the transverse fiber connections between collagen gradually increased and thickened,suggesting that the strength and shape degree of the grafts were gradually improved,but the ligament remodeling in the relaxation group was always faster than that in the normal group at various time points after surgery.(3)The diameter,distribution density,and arrangement degree of collagen fibers in the relaxation group were better than those in the normal group at all time points,especially in the comparison of collagen fiber diameter between and within the relaxation group(P<0.05).
7.Biocompatibility of poly(vinylidene fluoride)piezoelectric bionic periosteum prepared by electrospinning
Shuai ZHAO ; Dongyao LI ; Suiyan WEI ; Yijing CAO ; Yan XU ; Guoqiang XU
Chinese Journal of Tissue Engineering Research 2025;29(4):730-737
BACKGROUND:Our previous studies have found that poly(vinylidene fluoride)bionic periosteum prepared by electrospinning has good cytocompatibility,but its biocompatibility is unknown. OBJECTIVE:To evaluate the biocompatibility of poly(vinylidene fluoride)bionic periosteum doped with Zn2+and Mg2+. METHODS:Poly(vinylidene fluoride),poly(vinylidene fluoride)bionic periosteum doped with 1%Zn2+,doped with 1%Mg2+,and doped with 1%(Zn2++Mg2+)were prepared by electrospinning to make bionic periosteum extract.SD rats were selected as the experimental subjects for hemolysis test,short-term systemic toxicity test,and heat source test.Guinea pigs were selected as the experimental subjects for skin sensitization test.The biocompatibility of bionic periosteum of four groups was tested. RESULTS AND CONCLUSION:(1)The hemolysis test results showed that the hemolysis rates of 1%Zn2+poly(vinylidene fluoride),1%Mg2+poly(vinylidene fluoride),1%Zn2++1%Mg2+poly(vinylidene fluoride)bionic periosteum and poly(vinylidene fluoride)extract were(0.130±0.013)%,(0.149±0.020)%,(0.466±0.018)%,and(0.037±0.018)%,respectively,which met the hemocompatibility standard of biomaterials.(2)The results of short-term systemic toxicity test showed that the four groups of bionic periosteal extract had no toxic signs such as body mass reduction,food intake changes,and dyspnea in SD rats,and had no toxic effects on major organs of rats.(3)Heat source test results showed that after intervention with poly(vinylidene fluoride)bionic periosteum doped with 1%Zn2+,doped with 1%Mg2+,and doped with 1%(Zn2++Mg2+),and poly(vinylidene fluoride)bionic periosteum extract,the elevated body temperature values of SD rats were(0.133±0.058),(0.100±0.010),(0.300±0.010),and(0.300±0.017)℃respectively.All were less than 0.6 ℃and the total temperature increase was less than 1.4 ℃.(4)The results of skin sensitization test showed that no erythema or edema was observed under the skin of guinea pigs after the intervention of bionic periosteum extract of four groups.(5)The results showed that poly(vinylidene fluoride)and poly(vinylidene fluoride)bionic periosteum doped with Zn2+and Mg2+had good biocompatibility.
8.Stress distribution on the maxilla when wearing the Twin-block appliance for Class Ⅱ malocclusion
Shuai LI ; Hua LIU ; Yonghui SHANG ; Yicong LIU ; Qihang ZHAO ; Wen LIU
Chinese Journal of Tissue Engineering Research 2025;29(5):881-887
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.
9.Effect of transcranial magneto-acousto-electrical stimulation on the plasticity of the prefrontal cortex network in mice
Shuai ZHANG ; Zichun LI ; Yihao XU ; Xiaofeng XIE ; Zhongsheng GUO ; Qingyang ZHAO
Chinese Journal of Tissue Engineering Research 2025;29(6):1108-1117
BACKGROUND:Transcranial magneto-acoustic-electrical stimulation is a novel non-invasive neural regulation technique that utilizes the induced electric field generated by the coupling effect of ultrasound and static magnetic field to regulate the discharge activity of the nervous system.However,the mechanism by which it affects synaptic plasticity in the brain is still not enough. OBJECTIVE:To explore the effect of transcranial magneto-acoustic-electrical stimulation intensity on synaptic plasticity of the prefrontal cortex neural network in mice. METHODS:(1)Animal experiment:Twenty-four C57 mice were equally and randomly divided into four groups:the control group receiving pseudo-stimulation,the 6.35 W/cm2 stimulation group receiving coupled stimulation of 0.3 T,6.35 W/cm2,the 17.36 W/cm2 stimulation group receiving coupled stimulation of 0.3 T,17.36 W/cm2,and the 56.25 W/cm2 stimulation group receiving coupled stimulation of 0.3 T,56.25 W/cm2.The local field potential signals and behavioral correctness were recorded during the execution of T-maze in mice.(2)Modeling and simulation experiments:A neural network model of the prefrontal cortex in mice stimulated by transcranial magneto-acoustic-electrical stimulation was constructed to compare the structural connectivity characteristics of the neural network under different stimulation intensities. RESULTS AND CONCLUSION:Transcranial magneto-acoustic-electrical stimulation could effectively shorten the behavior learning time,improve the working memory ability of mice(P<0.05),and continue to stimulate the frontal lobe of mice after learning behavior.There was no significant difference in the accuracy of the T-maze behavioral experiment among the experimental groups(P>0.1).Analysis of local field potential signals in the frontal lobe of mice revealed that transcranial magneto-acoustic-electrical stimulation promoted energy enhancement of β and γ rhythms.As the stimulation intensity increased,there was an asynchronous decrease in β and γ rhythms.Through β-γ phase amplitude coupling,it was found that stimuli could enhance the neural network's ability to adapt to new information and task requirements.Modeling and simulation experiments found that stimulation could enhance the discharge level of the neural network,increase the long-term synaptic weight level,and decrease the short-term synaptic weight level only when the stimulation intensity was high.To conclude,there is a complex nonlinear relationship between different stimulus intensities and the functional structure of neural networks.This neural regulation technique may provide new possibilities for the treatment of related neurological diseases such as synaptic dysfunction and neural network abnormalities.
10.Modified double-bundle arthroscopic repair of the anterior cruciate ligament after Sherman type Ⅰ injury
Changbing WANG ; Lilian ZHAO ; Chuying FU ; Yanjin LI
Chinese Journal of Tissue Engineering Research 2025;29(6):1192-1198
BACKGROUND:Impaired hamstring muscle strength,anterior patellar pain,high incidence of osteoarthritis,and loss of proprioception after anterior cruciate ligament reconstruction lead to poor functional recovery due to a higher incidence of osteoarthritis and loss of proprioception.Arthroscopic repair of the anterior cruciate ligament combined with dynamic or static internal brace repair preserves the original ligament structure and results in favorable short-term outcomes. OBJECTIVE:To prospectively observe the efficacy and imaging findings of modified double-bundle arthroscopic repair of the anterior cruciate ligament after Sherman type Ⅰ injury METHODS:From January 2020 to September 2022,a total of 60 patients with anterior cruciate ligament injury admitted at the Department of Sports Medicine,Foshan Hospital of Traditional Chinese Medicine were included and divided into two groups(n=30 per group)according to the treatment protocols.The functional repair group was treated with double bundle repair combined with internal brace fixation,and the reconstruction group was treated with single bundle anatomical reconstruction of autologous hamstring muscle.All cases were followed up for 12 months after surgery,and International Knee Documentation Committee score,Lysholm score and KT-1000 difference between the affected and healthy sides of the two groups were evaluated at 3,6 and 12 months after surgery. RESULTS AND CONCLUSION:Three months after surgery,International Knee Documentation Committee scores,Lysholm scores and KT-1000 difference between the affected and healthy sides were significantly different between the two groups(P<0.05),and the functional repair group was better than the reconstruction group.At 6 and 12 months after surgery,there was no significant difference in International Knee Documentation Committee score,Lysholm score and KT-1000 difference between the two groups(P>0.05).To conclude,anterior cruciate ligament repair preserves the original ligament structure,avoids drilling larger marrow tracts and removing autologous tendons for reconstruction,reduces the damage to the original normal structure,and has fewer complications.Early postoperative efficacy is better than that of anterior cruciate ligament reconstruction with stumps,but there is no significant difference in the efficacy of the two groups 6 months after surgery.

Result Analysis
Print
Save
E-mail