1.Mechanical effect of mechanical wear of abutment screws on the Morse taper connection implant system:a three-dimensional finite element analysis
Chinese Journal of Tissue Engineering Research 2026;30(6):1375-1383
BACKGROUND:Abutment screw loosening is one of the most common mechanical complications in implant restoration.Mechanical wear,as a potential cause of thread loosening,warrants attention due to its impact on mechanical performance and long-term stability.However,studies on the mechanical effects of thread wear in abutment screws remain limited,and no definitive conclusions have been reached.OBJECTIVE:To investigate the effect of different degrees of mechanical wear on the spatial stress distribution of the Morse taper connection implant system,with a view to providing a theoretical basis for the clinical assessment of the long-term stability of dental implants.METHODS:Three-dimensional finite element models of Morse taper implants with central screw thread wear levels of 0,0.1,1,10,and 100 μm were established using SolidWorks software,and simulation analysis with Ansys Workbench software was performed.The implant models were inserted into artificial bone blocks(simulating type Ⅱ bone,with a cortical bone thickness of 2 mm on the outer layer and cancellous bone inside).An alternating load of 300 N in the buccolingual direction was applied at the centroid of the abutment(forming an angle of 30° with the long axis of the implant).The von Mises stress,principal stress,displacement,and fatigue life of the abutment,central screw,implant,and bone tissue in the five groups of models were analyzed.RESULTS AND CONCLUSION:(1)As the degree of mechanical wear on the central screw thread increased,the von Mises stress,principal stress,and strain in the implant and abutment also increased.The stress in the model was concentrated at the top of the implant,at the shoulder level of the implant,at the neck of the abutment,and at the bottom edge of the abutment.(2)Under moderate wear conditions(≥ 10 μm),the fatigue life of the implant system decreased by 30%,and the maximum von Mises stress of the central screw decreased by 37%,with the stress still primarily concentrated at the transition area between the head and the body of the central screw.(3)Under significant wear conditions(≥ 100 μm),the von Mises stress of the central screw decreased by 98%,with the stress concentrated at the screw head,and the fatigue life of the implant system decreased by 63%.Therefore,when the wear level of the central screw thread reaches ≥ 10 μm,the risk of screw loosening is significantly increased,and the fatigue life of the implant system is markedly reduced,warranting clinical attention.
2.Mechanical effect of mechanical wear of abutment screws on the Morse taper connection implant system:a three-dimensional finite element analysis
Chinese Journal of Tissue Engineering Research 2026;30(6):1375-1383
BACKGROUND:Abutment screw loosening is one of the most common mechanical complications in implant restoration.Mechanical wear,as a potential cause of thread loosening,warrants attention due to its impact on mechanical performance and long-term stability.However,studies on the mechanical effects of thread wear in abutment screws remain limited,and no definitive conclusions have been reached.OBJECTIVE:To investigate the effect of different degrees of mechanical wear on the spatial stress distribution of the Morse taper connection implant system,with a view to providing a theoretical basis for the clinical assessment of the long-term stability of dental implants.METHODS:Three-dimensional finite element models of Morse taper implants with central screw thread wear levels of 0,0.1,1,10,and 100 μm were established using SolidWorks software,and simulation analysis with Ansys Workbench software was performed.The implant models were inserted into artificial bone blocks(simulating type Ⅱ bone,with a cortical bone thickness of 2 mm on the outer layer and cancellous bone inside).An alternating load of 300 N in the buccolingual direction was applied at the centroid of the abutment(forming an angle of 30° with the long axis of the implant).The von Mises stress,principal stress,displacement,and fatigue life of the abutment,central screw,implant,and bone tissue in the five groups of models were analyzed.RESULTS AND CONCLUSION:(1)As the degree of mechanical wear on the central screw thread increased,the von Mises stress,principal stress,and strain in the implant and abutment also increased.The stress in the model was concentrated at the top of the implant,at the shoulder level of the implant,at the neck of the abutment,and at the bottom edge of the abutment.(2)Under moderate wear conditions(≥ 10 μm),the fatigue life of the implant system decreased by 30%,and the maximum von Mises stress of the central screw decreased by 37%,with the stress still primarily concentrated at the transition area between the head and the body of the central screw.(3)Under significant wear conditions(≥ 100 μm),the von Mises stress of the central screw decreased by 98%,with the stress concentrated at the screw head,and the fatigue life of the implant system decreased by 63%.Therefore,when the wear level of the central screw thread reaches ≥ 10 μm,the risk of screw loosening is significantly increased,and the fatigue life of the implant system is markedly reduced,warranting clinical attention.
3.Leveraging genetic differences and Mendelian randomization to dissect the causal link and shared etiology between diabetic nephropathy and diabetic retinopathy
Guoxin DING ; Jing WANG ; Xian WANG ; Zhou ZHANG ; Xin XIAO ; Yingqi LI
International Eye Science 2025;25(11):1838-1847
AIM: To investigate the genetic association and potential causal relationship between diabetic nephropathy(DN)and diabetic retinopathy(DR), and to elucidate their shared molecular mechanisms through differential gene expression analysis and Mendelian randomization(MR).METHODS: Transcriptomic data of DN and DR were obtained from the Gene Expression Omnibus(GEO)database and analyzed for differentially expressed genes(DEGs). Genes meeting the significance threshold(log2FC>1, P<0.05)were identified, followed by Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis to explore shared biological pathways. Using genome-wide association study(GWAS)summary statistics for DN and DR, two-sample MR analysis was performed, with DN as the exposure and DR as the outcome. The causal effect was primarily estimated with the inverse-variance weighted(IVW)method, and sensitivity analyses were conducted to assess robustness.RESULTS: MR analysis revealed that DN significantly increased the risk of DR. IVW estimates indicated that the odds ratio(OR)for non-proliferative DR(NPDR)was 3.23(95% CI: 2.12-4.95, P<0.001), and the OR for proliferative DR(PDR)was 1.10(95% CI: 1.06-1.15, P<0.001). DEG analysis identified several key genes, including FN1, COL1A2, and THBS2. FN1 and COL1A2 are involved in extracellular matrix remodeling and fibrosis, contributing to vascular permeability alterations and microvascular damage in diabetic complications. THBS2 is closely associated with angiogenesis and vascular homeostasis, suggesting its potential role in DR. KEGG enrichment analysis showed that these DEGs were mainly enriched in advanced glycation end products(AGEs)-RAGE signaling, extracellular matrix degradation, and oxidative stress pathways, all of which are highly relevant to the pathogenesis of DN and DR.CONCLUSION: This study demonstrates the genetic association between DN and DR using MR and DEGs analyses. The shared mechanisms, particularly involving extracellular matrix remodeling, inflammatory response, and angiogenesis, may serve as novel therapeutic targets and provide a theoretical basis for the early diagnosis and targeted treatment of diabetic complications.
4.Expert consensus on the positioning of the "Three-in-One" Registration and Evaluation Evidence System and the value of orientation of the "personal experience"
Qi WANG ; Yongyan WANG ; Wei XIAO ; Jinzhou TIAN ; Shilin CHEN ; Liguo ZHU ; Guangrong SUN ; Daning ZHANG ; Daihan ZHOU ; Guoqiang MEI ; Baofan SHEN ; Qingguo WANG ; Xixing WANG ; Zheng NAN ; Mingxiang HAN ; Yue GAO ; Xiaohe XIAO ; Xiaobo SUN ; Kaiwen HU ; Liqun JIA ; Li FENG ; Chengyu WU ; Xia DING
Journal of Beijing University of Traditional Chinese Medicine 2025;48(4):445-450
Traditional Chinese Medicine (TCM), as a treasure of the Chinese nation, plays a significant role in maintaining public health. In 2019, the Central Committee of the Communist Party of China and the State Council proposed for the first time the establishment of a TCM registration and evaluation evidence system that integrates TCM theory, "personal experience" and clinical trials (referred to as the "Three-in-One" System) to promote the inheritance and innovation of TCM. Subsequently, the National Medical Products Administration issued several guiding principles to advance the improvement and implementation of this system. Owing to the complexity of its implementation, there are still differing understandings within the TCM industry regarding the positioning of the "Three-in-One" Registration and Evaluation Evidence System, as well as the connotation and value orientation of the "personal experience." To address this, Academician WANG Qi, President of the TCM Association, China International Exchange and Promotion Association for Medical and Healthcare and TCM master, led a group of academicians, TCM masters, TCM pharmacology experts and clinical TCM experts to convene a "Seminar on Promoting the Implementation of the ′Three-in-One′ Registration and Evaluation Evidence System for Chinese Medicinals." Through extensive discussions, an expert consensus was formed, clarifying the different roles of the TCM theory, "personal experience" and clinical trials within the system. It was further emphasized that the "personal experience" is the core of this system, and its data should be derived from clinical practice scenarios. In the future, the improvement of this system will require collaborative efforts across multiple fields to promote the high-quality development of the Chinese medicinal industry.
5.Genome-wide DNA methylation and mRNA transcription analysis revealed aberrant gene regulation pathways in patients with dermatomyositis and polymyositis.
Hui LUO ; Honglin ZHU ; Ding BAO ; Yizhi XIAO ; Bin ZHOU ; Gong XIAO ; Lihua ZHANG ; Siming GAO ; Liya LI ; Yangtengyu LIU ; Di LIU ; Junjiao WU ; Qiming MENG ; Meng MENG ; Tao CHEN ; Xiaoxia ZUO ; Quanzhen LI ; Huali ZHANG
Chinese Medical Journal 2025;138(1):120-122
6.Decoding the genetic and environmental forces in propelling the surge of early-onset colorectal cancer.
Jianhui ZHAO ; Haosen JI ; Kangning LI ; Guirong YU ; Siyun ZHOU ; Qian XIAO ; Malcolm DUNLOP ; Evropi THEODORATOU ; Xue LI ; Kefeng DING
Chinese Medical Journal 2025;138(10):1163-1174
Early-onset colorectal cancer (EOCRC) shows a different epidemiological trend compared to later-onset colorectal cancer, with its incidence rising in most regions and countries worldwide. However, the reasons behind this trend remain unclear. The etiology of EOCRC is complex and could involve both genetic and environmental factors. Apart from Lynch syndrome and Familial Adenomatous Polyposis, sporadic EOCRC exhibits a broad spectrum of pathogenic germline mutations, genetic polymorphisms, methylation changes, and chromosomal instability. Early-life exposures and environmental risk factors, including lifestyle and dietary risk factors, have been found to be associated with EOCRC risk. Meanwhile, specific chronic diseases, such as inflammatory bowel disease, diabetes, and metabolic syndrome, have been associated with EOCRC. Interactions between genetic and environmental risk factors in EOCRC have also been explored. Here we present findings from a narrative review of epidemiological studies on the assessment of early-life exposures, of EOCRC-specific environmental factors, and their interactions with susceptible loci. We also present results from EOCRC-specific genome-wide association studies that could be used to perform Mendelian randomization analyses to ascertain potential causal links between environmental factors and EOCRC.
Humans
;
Colorectal Neoplasms/etiology*
;
Risk Factors
;
Genome-Wide Association Study
;
Genetic Predisposition to Disease/genetics*
7.Differences in growth and secondary metabolite accumulation of Panax quinquefolius between understory and field planting in Shandong, China.
Yue WANG ; Xin-Ying MAO ; Yu DING ; Hong-Xia YU ; Zhi-Fang RAN ; Xiao-Li CHEN ; Jie ZHOU
China Journal of Chinese Materia Medica 2025;50(6):1524-1533
In order to compare the differences in growth and secondary metabolite accumulation of Panax quinquefolius between understory and field planting, growth indexes, photosynthetic characteristics, soil enzyme activities, secondary metabolite contents, and antioxidant activities of P. quinquefolius under different planting modes were examined and compared, and One-way analysis of variance(ANOVA) and correlation analyses were carried out by using the software SPSS 25.0 and GraphPad Prism 9.5. The Origin 2021 software was used for plotting. The results showed that compared with those under field planting, the plant height, leaf length, leaf width, photosynthetic rate, and chlorophyll content of P. quinquefolius under understory planting were significantly reduced, and arbuscular mycorrhizal fungi(AMF) infestation rate and infestation intensity, ginsenoside content, and antioxidant activity were significantly increased. The activities of inter-root soil urease, sucrase, and catalase increased, while the activities of non-inter-root soil urease and alkaline phosphatase increased. Correlation analyses showed that the plant height and leaf length of P. quinquefolius plant were significantly positively correlated with net photosynthetic rate, transpiration rate, chlorophyll content, and electron transfer rate(P<0.05), while ginsenoside content was significantly negatively correlated with net photosynthetic rate, chlorophyll content, and electron transfer rate(P<0.05) and significantly positively correlated with AMF infestation rate and infestation intensity(P<0.05). In addition, ginsenoside content was significantly positively correlated with the activities of inter-root soil sucrase, urease, and catalase(P<0.05). This study provides basic data for revealing the mechanism of secondary metabolite accumulation in P. quinquefolius under understory planting and for exploring and practicing the ecological mode of P. quinquefolius under understory planting.
Panax/microbiology*
;
China
;
Secondary Metabolism
;
Soil/chemistry*
;
Photosynthesis
;
Plant Leaves/metabolism*
;
Chlorophyll/metabolism*
;
Mycorrhizae
8.Four new diglycosides from Momordicae Semen.
Cheng-Lin ZHOU ; Xiao-Bo LI ; Pei-Jun JU ; Ru DING ; Meng-Yue WANG
China Journal of Chinese Materia Medica 2025;50(6):1558-1563
The seed kernel of Momordica cochinchinensis, i.e., Momordicae Semen, is used for medicinal purposes, but to date, no research has been reported on its chemical constituents. In this study, the chemical constituents of Momordicae Semen were investigated for the first time using silica gel column chromatography, semi-preparative HPLC, HR-MS, and NMR. As a result, eight compounds were isolated and identified as: p-hydroxybenzoic acid-7-O-trehaloside(mubeside A, 1), 2,6-dimethoxyphenol-O-β-D-apiosyl-(1→2)-β-D-glucoside(mubeside B, 2), 1-O-p-methoxybenzoyl-1,4-benzenediol-4-O-β-D-apiosyl-(1→2)-β-D-glucoside(mubeside C, 3), 1-O-p-hydroxybenzoyl-1,4-benzenediol-4-O-β-D-apiosyl-(1→2)-β-D-glucoside(mubeside D, 4), gypsogenin-3-O-β-D-galactosyl-(1→2)-β-D-glucuronoside(5), quillaic acid-3-O-β-D-galactosyl-(1→2)-β-D-glucuronoside(6), violanthin(7), and kaempferitrin(8). Compounds 1-4 are new compounds, while compounds 5-8 were isolated from Momordicae Semen for the first time.
Glycosides/isolation & purification*
;
Drugs, Chinese Herbal/isolation & purification*
;
Molecular Structure
;
Magnetic Resonance Spectroscopy
;
Chromatography, High Pressure Liquid
9.Clinical study of modified high tibial osteotomy combined with platelet-rich plasma in the treatment of moderate to severe knee osteoarthritis.
Xiao-Min LI ; Xiang-Dong TIAN ; Ye-Tong TAN ; Tian-Song DING
China Journal of Orthopaedics and Traumatology 2025;38(4):329-335
OBJECTIVE:
To evaluate the clinical efficacy of modified high tibial osteotomy combined with platelet-rich plasma in the treatment of moderate to severe knee osteoarthritis.
METHODS:
From January 2021 to March 2022, the clinical data of 60 patients with moderate to severe knee osteoarthritis admitted to the Third Affiliated Hospital of Beijing University of Chinese Medicine were analyzed. Among them, 30 patients were treated with modified tibia high osteotomy combined with platelet-rich plasma as the observation group, including 12 males and 18 females, aged from 51 to 74 years old, with an average age of (64.37±5.72) years old. The course of disease ranged from 1 to 7 years with an average of(3.43±1.41) years. Thirty patients were treated with modified high tibial osteotomy combined with sodium hyaluronate as control group, including 10 males and 20 females, aged from 50 to 78 years, with an average age of (64.33±8.18) years. The course of disease was 1 to 7 years with an average of(3.30±1.39) years. Knee X-rays were taken before surgery and at the last follow-up, and the changes of lower limb bearing-line ratio (WBLR), proximal medial tibial Angle (MPTA), femoro-tibial angle (FTA) and posterior tibial slope (PTS) were compared between the two times. Visual analogue scale (VAS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Lysholm score were used to evaluate knee pain and functional changes before surgery and at 1, 3, and 6 months after surgery.
RESULTS:
The wounds of all patients healed in stage I after surgery. All 60 patients completed treatment and follow-up, with an average follow-up duration of (8.08±1.75) months, ranged from 6 to 12 months. No serious adverse events or complications occurred. At the last follow-up, WBLR, MPTA and FTA were significantly improved in both groups (P<0.05). At the last follow-up, there was no significant difference in PTS between the two groups compared with pre-operation(P>0.05). At the last follow-up, there were no significant differences in WBLR, MPTA, FTA and PTS between the observation group and the control group (P>0.05). The VAS scores, WOMAC scores and Lysholm scores of both groups were significantly Modified with time after operation (P<0.05). At 1, 3 and 6 months after operation, VAS score, WOMAC score and Lysholm score of the observation group were significantly better than those of the control group, with statistical significance (P<0.05).
CONCLUSION
For patients with moderate and severe knee osteoarthritis, modified high tibial osteotomy can significantly correct lower limb alignment, and combined with platelet-rich plasma therapy can further significantly relieve knee pain and improve knee function, the effect is better than combined with sodium hyaluronate.
Humans
;
Male
;
Female
;
Osteoarthritis, Knee/physiopathology*
;
Middle Aged
;
Osteotomy/methods*
;
Platelet-Rich Plasma
;
Aged
;
Tibia/surgery*
10.Prediction of testicular histology in azoospermia patients through deep learning-enabled two-dimensional grayscale ultrasound.
Jia-Ying HU ; Zhen-Zhe LIN ; Li DING ; Zhi-Xing ZHANG ; Wan-Ling HUANG ; Sha-Sha HUANG ; Bin LI ; Xiao-Yan XIE ; Ming-De LU ; Chun-Hua DENG ; Hao-Tian LIN ; Yong GAO ; Zhu WANG
Asian Journal of Andrology 2025;27(2):254-260
Testicular histology based on testicular biopsy is an important factor for determining appropriate testicular sperm extraction surgery and predicting sperm retrieval outcomes in patients with azoospermia. Therefore, we developed a deep learning (DL) model to establish the associations between testicular grayscale ultrasound images and testicular histology. We retrospectively included two-dimensional testicular grayscale ultrasound from patients with azoospermia (353 men with 4357 images between July 2017 and December 2021 in The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China) to develop a DL model. We obtained testicular histology during conventional testicular sperm extraction. Our DL model was trained based on ultrasound images or fusion data (ultrasound images fused with the corresponding testicular volume) to distinguish spermatozoa presence in pathology (SPP) and spermatozoa absence in pathology (SAP) and to classify maturation arrest (MA) and Sertoli cell-only syndrome (SCOS) in patients with SAP. Areas under the receiver operating characteristic curve (AUCs), accuracy, sensitivity, and specificity were used to analyze model performance. DL based on images achieved an AUC of 0.922 (95% confidence interval [CI]: 0.908-0.935), a sensitivity of 80.9%, a specificity of 84.6%, and an accuracy of 83.5% in predicting SPP (including normal spermatogenesis and hypospermatogenesis) and SAP (including MA and SCOS). In the identification of SCOS and MA, DL on fusion data yielded better diagnostic performance with an AUC of 0.979 (95% CI: 0.969-0.989), a sensitivity of 89.7%, a specificity of 97.1%, and an accuracy of 92.1%. Our study provides a noninvasive method to predict testicular histology for patients with azoospermia, which would avoid unnecessary testicular biopsy.
Humans
;
Male
;
Azoospermia/diagnostic imaging*
;
Deep Learning
;
Testis/pathology*
;
Retrospective Studies
;
Adult
;
Ultrasonography/methods*
;
Sperm Retrieval
;
Sertoli Cell-Only Syndrome/diagnostic imaging*


Result Analysis
Print
Save
E-mail