1.Finite element analysis of implants with different crown-to-implant ratios under different bone conditions
Zirui KANG ; Yang WU ; Hailong SONG ; Qiaoyun YANG ; Lixiang ZANG ; Dongliang XU
Chinese Journal of Tissue Engineering Research 2026;30(2):319-328
BACKGROUND:Clinical studies suggest that both bone quality and excessive crown-to-implant ratio are factors that affect the success rate of implant surgery,but there is no consensus on how large the crown-to-implant ratio under each bone quality will affect the prognosis of implant repair.OBJECTIVE:To analyze the stress and strain of bone tissue around implant restorations with different crown-to-implant ratios under different bone types after stress loading using three-dimensional finite element method.Combined with the Frost bone mechanics regulation system theory,the physiological limits of bone strain were observed for each bone type within a certain range of crown to implant ratios.METHODS:Cone beam CT data were selected from a patient to establish solid bone block models with four different bone types(class Ⅰ bone:cortical bone thickness 3 mm+dense cancellous bone,class Ⅱ bone:cortical bone thickness 2 mm+relatively dense cancellous bone,class Ⅲ bone:cortical bone thickness 1 mm+relatively low-density cancellous bone,class Ⅳ bone:cortical bone thickness 1 mm+low-density cancellous bone).Implant restorations with five different crown-to-implant ratios(1,1.5,2,2.5,and 3)were created on each bone block model,for a total of 20 models.Vertical and oblique forces were applied to the dental crown to observe the von Mises stress values,strains,and displacement of the cortical and cancellous bones,as well as the degree of implant displacement.RESULTS AND CONCLUSION:(1)In the class Ⅰ bone model,when the crown-to-implant ratio reached 3 under oblique loading,the cortical bone strain exceeded the physiological limit.In the class Ⅱ bone model,under oblique loading,when the crown-to-implant ratio reached 2.5,the cortical bone strain exceeded the physiological limit.In the class Ⅲ bone model,under oblique loading,cortical bone exceeded the physiological limit when the crown-to-implant ratio reached 2.5,while cancellous bone reached the critical physiological limit at 1.In the class Ⅳ bone model,under oblique loading,when the crown-to-implant ratio reached 1.5,2,2.5,and 3,the cortical bone strain exceeded the physiological limit.In the class Ⅳ bone model,all five crown-to-implant ratios of cancellous bone exceeded physiological limits.(2)Under vertical load,the cancellous bone strain exceeded the physiological limit when the crown-root ratio reached 1,2,2.5,and 3 in the class Ⅲ bone model,and when the cancellous bone strain of the five crown-root ratios in the class Ⅳ bone model exceeded the physiological limit.(3)Under oblique or vertical load,the implant displacement of the 20 groups of models did not exceed 100 μm.(4)From the perspective of biomechanics,when patients with insufficient bone height choose implant restoration,the crown-root ratio that class Ⅰ bone can tolerate is up to 2.5 times,the crown-root ratio that class Ⅱ bone can tolerate is up to 2 times,and the crown-root ratio that class Ⅲ and class Ⅳ bones can tolerate is up to 1 times due to excessive strain of cancellous bone;but the crown-root ratio that cortical bone in class Ⅲ bone can tolerate is up to 2 times.Whether class Ⅲ bone can tolerate implant restoration with a high crown-root ratio and whether cancellous bone can tolerate higher strains needs further study.
2.Finite element analysis of implants with different crown-to-implant ratios under different bone conditions
Zirui KANG ; Yang WU ; Hailong SONG ; Qiaoyun YANG ; Lixiang ZANG ; Dongliang XU
Chinese Journal of Tissue Engineering Research 2026;30(2):319-328
BACKGROUND:Clinical studies suggest that both bone quality and excessive crown-to-implant ratio are factors that affect the success rate of implant surgery,but there is no consensus on how large the crown-to-implant ratio under each bone quality will affect the prognosis of implant repair.OBJECTIVE:To analyze the stress and strain of bone tissue around implant restorations with different crown-to-implant ratios under different bone types after stress loading using three-dimensional finite element method.Combined with the Frost bone mechanics regulation system theory,the physiological limits of bone strain were observed for each bone type within a certain range of crown to implant ratios.METHODS:Cone beam CT data were selected from a patient to establish solid bone block models with four different bone types(class Ⅰ bone:cortical bone thickness 3 mm+dense cancellous bone,class Ⅱ bone:cortical bone thickness 2 mm+relatively dense cancellous bone,class Ⅲ bone:cortical bone thickness 1 mm+relatively low-density cancellous bone,class Ⅳ bone:cortical bone thickness 1 mm+low-density cancellous bone).Implant restorations with five different crown-to-implant ratios(1,1.5,2,2.5,and 3)were created on each bone block model,for a total of 20 models.Vertical and oblique forces were applied to the dental crown to observe the von Mises stress values,strains,and displacement of the cortical and cancellous bones,as well as the degree of implant displacement.RESULTS AND CONCLUSION:(1)In the class Ⅰ bone model,when the crown-to-implant ratio reached 3 under oblique loading,the cortical bone strain exceeded the physiological limit.In the class Ⅱ bone model,under oblique loading,when the crown-to-implant ratio reached 2.5,the cortical bone strain exceeded the physiological limit.In the class Ⅲ bone model,under oblique loading,cortical bone exceeded the physiological limit when the crown-to-implant ratio reached 2.5,while cancellous bone reached the critical physiological limit at 1.In the class Ⅳ bone model,under oblique loading,when the crown-to-implant ratio reached 1.5,2,2.5,and 3,the cortical bone strain exceeded the physiological limit.In the class Ⅳ bone model,all five crown-to-implant ratios of cancellous bone exceeded physiological limits.(2)Under vertical load,the cancellous bone strain exceeded the physiological limit when the crown-root ratio reached 1,2,2.5,and 3 in the class Ⅲ bone model,and when the cancellous bone strain of the five crown-root ratios in the class Ⅳ bone model exceeded the physiological limit.(3)Under oblique or vertical load,the implant displacement of the 20 groups of models did not exceed 100 μm.(4)From the perspective of biomechanics,when patients with insufficient bone height choose implant restoration,the crown-root ratio that class Ⅰ bone can tolerate is up to 2.5 times,the crown-root ratio that class Ⅱ bone can tolerate is up to 2 times,and the crown-root ratio that class Ⅲ and class Ⅳ bones can tolerate is up to 1 times due to excessive strain of cancellous bone;but the crown-root ratio that cortical bone in class Ⅲ bone can tolerate is up to 2 times.Whether class Ⅲ bone can tolerate implant restoration with a high crown-root ratio and whether cancellous bone can tolerate higher strains needs further study.
3.Oxidative stress in diabetes mellitus and its complications: From pathophysiology to therapeutic strategies.
Xingyu CHEN ; Na XIE ; Lixiang FENG ; Yujing HUANG ; Yuyao WU ; Huili ZHU ; Jing TANG ; Yuanyuan ZHANG
Chinese Medical Journal 2025;138(1):15-27
Oxidative stress due to aberrant metabolism is considered as a crucial contributor to diabetes and its complications. Hyperglycemia and hyperlipemia boost excessive reactive oxygen species generation by elevated mitochondrial respiration, increased nicotinamide adenine dinucleotide phosphate oxidase activity, and enhanced pro-oxidative processes, including protein kinase C pathways, hexosamine, polyol, and advanced glycation endproducts, which exacerbate oxidative stress. Oxidative stress plays a significant role in the onset of diabetes and its associated complications by impairing insulin production, increasing insulin resistance, maintaining hyperglycemic memory, and inducing systemic inflammation. A more profound comprehension of the molecular processes that link oxidative stress to diabetes is crucial to new preventive and therapeutic strategies. Therefore, this review discusses the mechanisms underlying how oxidative stress contributes to diabetes mellitus and its complications. We also summarize the current approaches for prevention and treatment by targeting the oxidative stress pathways in diabetes.
Oxidative Stress/physiology*
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Humans
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Diabetes Mellitus/physiopathology*
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Diabetes Complications/metabolism*
;
Reactive Oxygen Species/metabolism*
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Glycation End Products, Advanced/metabolism*
;
Animals
4.Comparative study of fecal SDC2,ADHFE1,and PPP2R5C gene methylation detection and fecal occult blood test in colorectal cancer screening
Juan FENG ; Liyu LIN ; Xueyun YE ; Yongtao WU ; Fengxin WU ; Lizhu XU ; Lixiang ZHOU
China Journal of Endoscopy 2025;31(7):31-36
Objective To compare the colonoscopy results of patients with positive fecal SDC2,ADHFE1,and PPP2R5C gene methylation tests to those with positive fecal occult blood tests,and analyze the effectiveness of colorectal cancer(CRC)screening.This study aims to provide a scientific basis for risk assessment in CRC screening.Methods From December 2023 to May 2024,9 284 combined test kits for SDC2,ADHFE1,and PPP2R5C gene methylation were distributed to high-risk individuals aged 40~80 years.Among them,841 patients(9.1%)tested positive.These patients were encouraged via telephone to undergo colonoscopy,with colonoscopy combined with pathological diagnosis as the gold standard,a total of 495 positive patients completed electronic colonoscopy.Among them,the 251 patients who tested positive for fecal SDC2,ADHFE1,and PPP2R5C gene methylation and completed electronic colonoscopy were the observation group;concurrently,244 patients who tested positive for fecal occult blood tests and underwent electronic colonoscopy were selected as the control group.Compare two groups of patients with polyp,number,shape,pathological changes and pathological types.Results There was no statistically significant difference in number and lesion location of polyps between the two groups of patients(P>0.05).The proportion of Yamada type Ⅰ in the observation group was lower than that in the control group,while the proportion of Yamada type Ⅱ was higher than that in the control group.The difference was statistically significant(P<0.05).In the observation group,1 case(0.4%)of CRC,62 cases(24.7%)of advanced adenomas,78 cases(31.1%)of non-advanced adenomas,20 cases(8.0%)of hyperplastic polyps,and 90 cases(35.9%)with no dysplastic lesions were identified.In the control group,6 cases(2.5%)of CRC,38 cases(15.6%)of advanced adenomas,53 cases(21.7%)of non-advanced adenomas,19 cases(7.8%)of hyperplastic polyps,and 128 cases(52.5%)with no dysplastic lesions were identified.The proportions of non-advanced adenomas and advanced adenomas were lower in the control group than those in the observation group,while the no dysplastic lesions rate was higher in the control group,the differences were statistically significant(P<0.05).Conclusion The detection rate of colorectal non-advanced adenomas and advanced adenomas is higher with fecal SDC2,ADHFE1,and PPP2R5C gene methylation testing compared to the fecal occult blood test.
5.Effect of silicate bioactive glass fiber on properties of calcium phosphate bone cement
Yuzheng LU ; Yingjie XIONG ; Yanbo SHAN ; Jianting YE ; Yanbin WU ; Jipeng SONG ; Yao ZHANG ; Wancheng LIN ; Qirui WENG ; Xuan CHENG ; Haoye MENG ; Wenjing XU ; Jiang PENG ; Lixiang DING
Chinese Journal of Tissue Engineering Research 2025;29(28):5994-6002
BACKGROUND:The development of calcium phosphate bone cement is limited due to its poor mechanical properties and weak osteogenic ability.Silicate bioactive glass is highly favored due to its excellent biological activity and osteogenic ability.Simultaneously,fiber structures can enhance the mechanical strength of materials.OBJECTIVE:To investigate the mechanical properties,biocompatibility,and osteogenic effect of silicate bioactive glass fiber composite calcium phosphate bone cement.METHODS:Different mass percentages(0%,10%,and 20%)of silicate bioactive glass fiber were added to the solid phase of calcium phosphate bone cement,mixed with the liquid phase and cured for 48 hours to obtain silicate bioactive glass fiber composite calcium phosphate bone cement.The mechanical properties,setting time,and ion precipitation of the cement were characterized.The three groups of bone cement extracts were co-cultured with MC3T3-E1 cells.The cell compatibility of the materials was evaluated by CCK-8 assay,live/dead staining,and phalloidin staining.After osteogenic induction,the osteogenic induction ability of the materials was evaluated by alkaline phosphatase staining,alizarin red staining,RUNX2 immunofluorescence staining,and RT-PCR.RESULTS AND CONCLUSION:(1)With the increase of silicate bioactive glass fiber content,the compressive strength and flexural strength of bone cement increased,and the setting time was prolonged.When bone cement was immersed in simulated body fluid,the precipitation of silicon ions,calcium ions,and phosphorus ions could be detected.Moreover,with the increase of silicate bioactive glass fiber content,the mass concentration of silicon ions and phosphorus ions released by bone cement increased,and the mass concentration of calcium ions decreased.(2)Live/dead staining and phalloidin staining results exhibited that silicate bioactive glass fiber composite calcium phosphate bone cement had no toxic effect on MC3T3-E1 cells.CCK-8 assay results showed that silicate bioactive glass fiber composite calcium phosphate bone cement could promote the proliferation of MC3T3-E1 cells.(3)With the increase of silicate bioactive glass fiber content in bone cement,the alkaline phosphatase activity and extracellular calcium deposition of MC3T3-E1 cells increased,the expression of RUNX2 protein increased,and the expression of alkaline phosphatase,osteocalcin,osteopontin,and RUNX2 mRNA expression increased.(4)The results indicate that silicate bioactive glass fibers can enhance the mechanical properties and osteogenic induction ability of calcium phosphate bone cement,among which 20%silicate bioactive glass fibers have a more obvious effect.
6.Comparative study of fecal SDC2,ADHFE1,and PPP2R5C gene methylation detection and fecal occult blood test in colorectal cancer screening
Juan FENG ; Liyu LIN ; Xueyun YE ; Yongtao WU ; Fengxin WU ; Lizhu XU ; Lixiang ZHOU
China Journal of Endoscopy 2025;31(7):31-36
Objective To compare the colonoscopy results of patients with positive fecal SDC2,ADHFE1,and PPP2R5C gene methylation tests to those with positive fecal occult blood tests,and analyze the effectiveness of colorectal cancer(CRC)screening.This study aims to provide a scientific basis for risk assessment in CRC screening.Methods From December 2023 to May 2024,9 284 combined test kits for SDC2,ADHFE1,and PPP2R5C gene methylation were distributed to high-risk individuals aged 40~80 years.Among them,841 patients(9.1%)tested positive.These patients were encouraged via telephone to undergo colonoscopy,with colonoscopy combined with pathological diagnosis as the gold standard,a total of 495 positive patients completed electronic colonoscopy.Among them,the 251 patients who tested positive for fecal SDC2,ADHFE1,and PPP2R5C gene methylation and completed electronic colonoscopy were the observation group;concurrently,244 patients who tested positive for fecal occult blood tests and underwent electronic colonoscopy were selected as the control group.Compare two groups of patients with polyp,number,shape,pathological changes and pathological types.Results There was no statistically significant difference in number and lesion location of polyps between the two groups of patients(P>0.05).The proportion of Yamada type Ⅰ in the observation group was lower than that in the control group,while the proportion of Yamada type Ⅱ was higher than that in the control group.The difference was statistically significant(P<0.05).In the observation group,1 case(0.4%)of CRC,62 cases(24.7%)of advanced adenomas,78 cases(31.1%)of non-advanced adenomas,20 cases(8.0%)of hyperplastic polyps,and 90 cases(35.9%)with no dysplastic lesions were identified.In the control group,6 cases(2.5%)of CRC,38 cases(15.6%)of advanced adenomas,53 cases(21.7%)of non-advanced adenomas,19 cases(7.8%)of hyperplastic polyps,and 128 cases(52.5%)with no dysplastic lesions were identified.The proportions of non-advanced adenomas and advanced adenomas were lower in the control group than those in the observation group,while the no dysplastic lesions rate was higher in the control group,the differences were statistically significant(P<0.05).Conclusion The detection rate of colorectal non-advanced adenomas and advanced adenomas is higher with fecal SDC2,ADHFE1,and PPP2R5C gene methylation testing compared to the fecal occult blood test.
7.Effect of silicate bioactive glass fiber on properties of calcium phosphate bone cement
Yuzheng LU ; Yingjie XIONG ; Yanbo SHAN ; Jianting YE ; Yanbin WU ; Jipeng SONG ; Yao ZHANG ; Wancheng LIN ; Qirui WENG ; Xuan CHENG ; Haoye MENG ; Wenjing XU ; Jiang PENG ; Lixiang DING
Chinese Journal of Tissue Engineering Research 2025;29(28):5994-6002
BACKGROUND:The development of calcium phosphate bone cement is limited due to its poor mechanical properties and weak osteogenic ability.Silicate bioactive glass is highly favored due to its excellent biological activity and osteogenic ability.Simultaneously,fiber structures can enhance the mechanical strength of materials.OBJECTIVE:To investigate the mechanical properties,biocompatibility,and osteogenic effect of silicate bioactive glass fiber composite calcium phosphate bone cement.METHODS:Different mass percentages(0%,10%,and 20%)of silicate bioactive glass fiber were added to the solid phase of calcium phosphate bone cement,mixed with the liquid phase and cured for 48 hours to obtain silicate bioactive glass fiber composite calcium phosphate bone cement.The mechanical properties,setting time,and ion precipitation of the cement were characterized.The three groups of bone cement extracts were co-cultured with MC3T3-E1 cells.The cell compatibility of the materials was evaluated by CCK-8 assay,live/dead staining,and phalloidin staining.After osteogenic induction,the osteogenic induction ability of the materials was evaluated by alkaline phosphatase staining,alizarin red staining,RUNX2 immunofluorescence staining,and RT-PCR.RESULTS AND CONCLUSION:(1)With the increase of silicate bioactive glass fiber content,the compressive strength and flexural strength of bone cement increased,and the setting time was prolonged.When bone cement was immersed in simulated body fluid,the precipitation of silicon ions,calcium ions,and phosphorus ions could be detected.Moreover,with the increase of silicate bioactive glass fiber content,the mass concentration of silicon ions and phosphorus ions released by bone cement increased,and the mass concentration of calcium ions decreased.(2)Live/dead staining and phalloidin staining results exhibited that silicate bioactive glass fiber composite calcium phosphate bone cement had no toxic effect on MC3T3-E1 cells.CCK-8 assay results showed that silicate bioactive glass fiber composite calcium phosphate bone cement could promote the proliferation of MC3T3-E1 cells.(3)With the increase of silicate bioactive glass fiber content in bone cement,the alkaline phosphatase activity and extracellular calcium deposition of MC3T3-E1 cells increased,the expression of RUNX2 protein increased,and the expression of alkaline phosphatase,osteocalcin,osteopontin,and RUNX2 mRNA expression increased.(4)The results indicate that silicate bioactive glass fibers can enhance the mechanical properties and osteogenic induction ability of calcium phosphate bone cement,among which 20%silicate bioactive glass fibers have a more obvious effect.
8.Predictive value of the differential distribution of peripheral lymphocyte subsets before and after the first 131I treatment on therapeutic response in patients with papillary thyroid cancer
Junyu ZHANG ; Di FAN ; Zhiyong SHI ; Tiane LUO ; Zhifang WU ; Hongliang WANG ; Keyi LU ; Suyun YANG ; Lixiang WU ; Tingting HU ; Yuanyuan MOU ; Sijin LI ; Haiyan LIU
Chinese Journal of Nuclear Medicine and Molecular Imaging 2024;44(12):730-735
Objective:To investigate the predictive value of differential distribution of peripheral lymphocyte subsets before and after the first 131I treatment on the therapeutic response to 131I treatment in patients with papillary thyroid cancer (PTC). Methods:A retrospective study was conducted on 46 PTC patients (16 males, 30 females, age 20-77 years) who underwent total thyroidectomy and received 131I treatment between January 2021 and August 2021 in First Hospital of Shanxi Medical University. Peripheral blood lymphocyte subsets (T, B, CD4 + T, CD8 + T, natural killer (NK), helper T (Th)1, Th2, Th17, and regulatory T (Treg) cells) were measured 1-2 d before and 30 d after 131I treatment. Based on serological and imaging evidence, therapeutic response at 6-12 months post- 131I therapy was categorized as either excellent response (ER) or non-excellent response (NER). Differences of preablative stimulated thyroglobulin (psTg) and clinical baseline characteristics between two groups were assessed by using independent-sample t test, paired t test, or Mann-Whitney U test. Predictive value of lymphocyte subsets before and after 131I treatment for therapeutic response was assessed through logistic regression analysis, ROC curve analysis, and decision curve analysis (DCA). Results:In ER group ( n=33) and NER group ( n=13), most lymphocyte subsets showed different degrees of reduction 30 d after 131I treatment compared to before 131I treatment, such as T, B, CD4 + T and Th1 cells in ER group, as well as T, B, CD4 + T, Th1, Th2, Th17, and Treg cells in NER group ( t values: 2.41-9.57, all P<0.05). Before 131I treatment, NER group had significantly higher levels of psTg, Th2, Th17, and Treg cells compared to the ER group ( t values: from -3.32 to -2.48, U=29.00, all P<0.05). After 131I treatment, most of lymphocyte subsets in NER group (T, B, CD4 + T, CD8 + T, Th1 and Treg cells) showed higher trend than those in ER group but without statistical significances ( t values: from -1.12 to -0.06, all P>0.05). Th2 cells before 131I treatment (odds ratio ( OR)=25.00, 95% CI: 1.36-459.10, P=0.030) was identified as a risk factor for NER. ROC curve analysis indicated that AUCs of psTg and Th2 cells for predicting therapeutic response were 0.932 and 0.790, respectively, which was 0.958 for the combined psTg and Th2 cells. DCA showed that within the threshold probability range of 10%-60%, the curves for psTg, Th2 cells, and the combined psTg and Th2 cells were all higher than the extreme curve, suggesting good effect. Conclusions:Most lymphocyte subsets decrease to varying degrees, and NER group shows a significant decrease 30 d after 131I treatment. Th2 cells may be a risk factor for poor response to 131I treatment, providing a certain value in predicting the therapeutic response to 131I treatment.
9.DNA Methylation of KLRC1 and KLRC3 in Autoimmune Thyroiditis:Perspective of Different Water Iodine Exposure
Chen YAO ; Liu JINJIN ; Qu MENGYING ; Ren BINGXUAN ; Wu HUAIYONG ; Zhang LI ; Zhou ZHENG ; Liu LIXIANG ; Shen HONGMEI
Biomedical and Environmental Sciences 2024;37(9):1044-1055
Objective This study aimed to identify differentially methylated genes (DMGs) associated with natural killer cells in patients with autoimmune thyroiditis (AIT),focusing on the influence of varying water iodine exposure levels. Methods Participants were divided into categories based on median water iodine (MWI) concentrations:iodine-fortified areas (IFA,MWI<10 μg/L),iodine-adequate areas (IAA,40 ≤ MWI ≤ 100μg/L),and iodine-excessive areas (IEA,MWI>300 μg/L). A total of 176 matched AIT cases and controls were recruited and divided into 89,40,and 47 pairs for IFA,IAA,and IEA,respectively. DMGs were identified using 850K BeadChip analysis for 10/10 paired samples. Validation of DNA methylation and mRNA expression levels of the DMGs was conducted using MethylTarget? and QRT-PCR for 176/176 paired samples. Results KLRC1,KLRC3,and SH2D1B were identified as significant DMGs. Validation revealed that KLRC1 was hypomethylated and highly expressed,whereas KLRC3 was hypermethylated and highly expressed in individuals with AIT. Furthermore,KLRC1 was hypomethylated and highly expressed in both IFA and IEA. Conclusion The DNA methylation status of KLRC1 and KLRC3 may play crucial roles in AIT pathogenesis. Additionally,DNA methylation of KLRC1 seems to be influenced by different iodine concentrations in water.
10.Modern Thinking on the Indications of Daoyin (导引) based on the Theory of "Wei (痿) Diseases should be Treated by Daoyin"
Yan YU ; Xueyin CHEN ; Lihong YANG ; Shaonan LIU ; Yu CHEN ; Lixiang LIU ; Ping YUE ; Jinpeng WU ; Xinfeng GUO
Journal of Traditional Chinese Medicine 2024;65(11):1170-1173
It has been proposed by Basic Questions On Proper Therapies for Different Diseases Geographically (《素问·异法方宜论篇》) that "wei (痿) diseases should be treated by Daoyin (导引)". Furthermore, it is clarified that the indications of Daoyin are those conditions related to spleen and dampness caused by dampness pathogen, excessive food intake and less exercise, and mainly manifested as heavy limbs, fatigue and flaccidity, which is similar to the metabolic imbalance in the early stage of glucose or lipid metabolism disorder in modern medicine. Based on modern clinical and basic research evidence, Daoyin can inhibit the response of inflammation, alleviate oxidative stress, regulate intestinal microbiota, and modulate gene expression to improve metabolic abnormalities, and this will provide ideas for researches on the indications of Daoyin.

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