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find Keyword "modeling" 102 results
  • Simulation method of skull remodellingsurgeryfor infant with craniosynostosis

    Craniofacial malformation caused by premature fusion of cranial suture of infants has a serious impact on their growth. The purpose of skull remodeling surgery for infants with craniosynostosis is to expand the skull and allow the brain to grow properly. There are no standardized treatments for skull remodeling surgery at the present, and the postoperative effect can be hardly assessed reasonably. Children with sagittal craniosynostosis were selected as the research objects. By analyzing the morphological characteristics of the patients, the point cloud registration of the skull distortion region with the ideal skull model was performed, and a plan of skull cutting and remodeling surgery was generated. A finite element model of the infant skull was used to predict the growth trend after remodeling surgery. Finally, an experimental study of surgery simulation was carried out with a child with a typical sagittal craniosynostosis. The evaluation results showed that the repositioning and stitching of bone plates effectively improved the morphology of the abnormal parts of the skull and had a normal growth trend. The child’s preoperative cephalic index was 65.31%, and became 71.50% after 9 months’ growth simulation. The simulation of the skull remodeling provides a reference for surgical plan design. The skull remodeling approach significantly improves postoperative effect, and it could be extended to the generation of cutting and remodeling plans and postoperative evaluations for treatment on other types of craniosynostosis.

    Release date:2021-12-24 04:01 Export PDF Favorites Scan
  • Research Progress of Correlation between Adipocytokines and Myocardial Remodeling

    Myocardial remodeling is a common pathological physiology change for a variety of heart diseases under stimulation such as stress or ischemia. The engine body will release a lot of cytokines to promote the change of myocardial structure and ultimately lead to heart failure. Myocardial remodeling includes myocardial cells remodeling and the extracellular matrix remodeling. In recent years, we find that the function of adipose tissue is not only about energy storage, buffering to protect, supporting and filling, but also has a powerful function of secretion. Adipose tissue can secrete various adipocytokines, such as leptin, adiponectin, visfatin, omentin, angiotensin Ⅱ, and so on. Current studies have shown that adipocytokines and myocardial remodeling are intimated. And this article will summarize the function of adipocytokines on myocardial remodeling.

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  • Bone remodeling after total hip arthroplasty with anatomic medullary locking prosthesis and its long-term effectiveness

    ObjectiveTo investigate the femoral bone remodeling and long-term effectiveness of total hip arthroplasty (THA) with anatomic medullary locking (AML) prosthesis.MethodsThe clinical data of 24 cases (26 hips) who were treated with THA with AML prosthesis between November 1997 and January 2003 were retrospectively analyzed. There were 12 males and 12 females with an age of 32-69 years (mean, 53.7 years). There were 5 cases (5 hips) of avascular necrosis of the femoral head, 6 cases (7 hips) of secondary osteoarthritis of the hip dysplasia, 6 cases (6 hips) of femoral neck fracture, 2 cases (2 hips) of primary osteoarthritis, 3 cases (3 hips) of revision surgery, 1 case (2 hips) of ankylosing spondylitis, 1 case (1 hip) of femoral head fracture. The patients were followed up at immediate, 6 weeks, 3 months, 6 months, 1 year, and then every year after operation for imaging evaluation (X-ray film was taken immediately after operation to evaluate the femoral isthmus compression, Engh standard was used to evaluate the biological fixation of the femoral shaft prosthesis, and Brooker method was used to evaluate the occurrence of heterotopic ossification); bone reconstruction evaluation [reconstruction of prosthesis and bone interface (type of bone reaction, Gruen zone, incidence, and occurrence time were recorded), reconstruction of bone around prosthesis (proximal femur stress shielding bone absorption was evaluated according to Engh and Bobyn methods, and bone mineral density change rate was measured)]; clinical efficacy evaluation [Harris score for efficacy, visual analogue scale (VAS) score for thigh pain].ResultsAll patients were followed up 15 years and 2 months to 20 years and 4 months, with a median of 16 years and 6 months. At immediate after operation, 24 hips (92.3%) had good femoral isthums compression, 24 hips (92.3%) had good bone ingrowth. Heterotopic ossification occurred in 2 patients with degree 1, 2 patients with degree 2, and 1 patient with degree 3 at 3-6 months after operation. Hyperplastic bone reactions were more common in Gruen 2, 3, 4, 5, 6, 10, 11, and 12 zones, mainly occurring at 6-20 months after operation, with the incidence of 3.8%-69.2%, with the highest incidence of spot welding. All absorptive bone reactions were osteolysis, which was common in Gruen 1 and 7 zones, and mainly occurred at 8 years after operation, with an incidence of 42.3%. No clear line (area) or enlarged sign of medullary cavity was observed. Twenty-one hips (80.8%) had 1 degree stress shieding, and 5 hips (19.2%) had 2 degree stress shieding. It mainly occurred at 10-24 months after operation in Gruen 1 and 7 zones. Dual energy X-ray absorptiometry showed that bone mineral density mainly decreased in Gruen 1, 2, 6, and 7 zones, mainly increased in Gruen 3, 4, and 5 zones. Bone mineral density loss progressed slowly after 2 years of operation, and it was stable in 5-8 years, but decreased rapidly in 8-9 years, and stabilized after 10 years. The Harris score increased from 51.1±6.2 before operation to 88.3±5.1 at last follow-up (t=–21.774, P=0.000). Mild thigh pain occurred in only 2 cases (7.7%) with the VAS score of 2. No aseptic loosening or revision of femoral prosthesis occurred during the follow-up.ConclusionThe application of AML prosthesis in THA has a good bone remodeling and a good long-term effectiveness.

    Release date:2020-07-07 07:58 Export PDF Favorites Scan
  • Effect of icariin on serum bone turnover markers expressions and histology changes in mouse osteoarthritis model

    ObjectiveTo investigate the effects of icariin (ICA) on serum bone turnover markers expressions and histological changes of cartilage and subchondral bone in mouse osteoarthritis (OA) model.MethodsEighty 8-week-old male C57BL/6J mouse were randomly divided into 8 groups (n=10). The OA model was established by anterior cruciate ligament transaction (ACLT). Group A: sham operation/early-stage normal saline administration; group B: sham operation/early-stage ICA administration; group C: ACLT/early-stage normal saline administration; group D: ACLT/early-stage ICA administration; group E: sham operation/late-stage normal saline administration; group F: sham operation/late-stage ICA administration; group G: ACLT/late-stage normal saline administration; group H: ACLT/late-stage ICA administration. Each animal received either ACLT or simply opening joint capsule, respectively. For groups B and D, ICA was given by gavage [10 mg/(kg·day)] on the first day after ACLT. For groups F and H, ICA was given with the same volume at 4 weeks after operation. The blood serum of the mouse was collected and prepared at 8 weeks after operation. Serum bone turnover markers and cytokines, including C-telopeptide of type I collagen (CTX), osteocalcin (OC), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and IL-1β, were measured by ELISA. Tissue samples from the knee were stained by alcian blue/hematoxylin & orange G (AB/H&OG). Histological changes of cartilage and subchondral bone were observed and evaluated by Osteoarthritis Research Society International (OARSI) scoring system.ResultsComparison between each group with early-stage administration (groups A, B, C, and D): Compared with groups A and B, the levels of CTX and OC in group C were significantly reduced (P<0.05); the levels of IL-6, TNF-α, and IL-1β and OARSI score was significantly increased (P<0.05). Compared with group C, the levels of CTX and OC in group D were significantly increased (P<0.05); the level of IL-6 was significantly reduced (P<0.05); the levels of TNF-α and IL-1β were not changed (P>0.05), and OARSI score was significantly reduced (P<0.05). Histological observation showed that the tibial cartilage loss was significantly improved. Comparison between each group with late-stage administration (groups E, F, G, and H): Compared with groups E and F, the levels of CTX and OC in group G were significantly reduced (P<0.05); the levels of IL-6, TNF-α, and IL-1β and OARSI score were significantly increased (P<0.05). Compared with group G, the level of CTX in group H were increased (P<0.05); the levels of OC, IL-6, TNF-α, and IL-1β and OARSI score were not changed (P>0.05). Histological observation showed that the tibial cartilage loss had no changes after late-stage ICA administration.ConclusionICA plays protective effects on subchondral bone, hyaline, and calcified cartilage. Meanwhile, ICA can improve bone remodeling in subchondral bone of OA to some extent. The consistent changes of serum bone markers and pathological morphology suggest that early intervention of ICA on OA is more effective.

    Release date:2017-08-03 03:46 Export PDF Favorites Scan
  • Effects of βreceptor Blocker on Intraventricular Pressure Gradient after Aortic Valve Replacement

    Abstract: Objective To investigate the effects of βreceptor blocker on intraventricular pressure gradient and left ventricle remodeling after valve replacement for critical aortic stenosis. Methods Fifty-six patients with critical aortic stenosis underwent aortic valve replacement surgery from January 2008 to January 2010 in the First Affiliated Hospital of Zhengzhou University. Thirtytwo of them who were followed up were selected to be enrolled in this study. The patients were divided into two groups under the same basis of clinical features. Twelve patients in the experimental group received oral βreceptor blocker (Metoprolol, 6.2525.00 mg once, twice daily). The rest 20 patients in the control group had no βreceptor blocker. The various indicators of ultrasound cardiogram (UCG) shortly after operation (within a week) and long after operation (6-24 months) were compared between the two groups. Results No death occurred in both groups, and chest distress, shortness of breath and other symptoms were obviously alleviated. Although left ventricular endsystolic dimension (LVESD) and left ventricular outflow tract dimension (LVOTD) of both groups increased 6-24 months after operation, compared with the early postoperative period, only the increase of LVOTD in the experimental group showed statistical difference (t=-47.937, P=0.001). In both groups, interventricular septum thickness (IVST), left ventricular posterior wall thickness (LVPWT), filament band velocity of left ventricular outflow tract (V), intraventricular pressure gradient (G) and left ventricular mass index (LVMI) of the later period after operation were significantly lower than those of the early postoperative period. All these indicators in the experimental group showed significant differences (t=7.781, P=0.001;t=5.749, P=0.001; t=2.637, P=0.023; t=7.167, P=0.001; t=100.061, P0.001), while only V, G, and LVMI showed statistical differences in the control group (t=4.051, P=0.001; t= 4.759, P= 0.001; t=-0.166,P=0.001). EF in the experimental group also indicated significant difference compared with early period after aortic valve replacement (t=-6.621, P=0.001). EF between two groups indicated no significant difference (t=-0.354,P=0.726). But differences between the two groups in LVEDD, IVS, G, and LVMI were all statistically significant in the later period after surgery (t=-2.494, P=0.018; t=-3.434, P=0.002;t=-2.171,P=0.038; t=-2.316, P=0.028). Conclusion β-receptor blocker is a safe and reliable drug for those patients who have undergone aortic valve replacement surgery for critical aortic stenosis, and can decrease significantly the residual intraventricular pressure gradient and accelerate left ventricular cardiac remodeling. 

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  • Research progress in geometric configuration design of artificial heart valve

    Valvular heart disease is a structural or functional disease of the heart due to rheumatic fever, congenital malformation, infection, or trauma, resulting in abnormal cardiac hemodynamics and ultimately heart failure. Implantation of artificial heart valves has become the main way to treat heart valvular disease. Because the structure of the artificial heart valve plays a key role in the stress distribution and hemodynamic performance of the valve and stent, the geometric configuration of the artificial heart valve is constantly updated and improved during its development from mechanical valve to biological valve, which closely mimics the geometric characteristics of the normal natural heart valve. This article sums up the design process of geometric configuration of artificial heart valves and the influence of geometric configuration on the central disc stress and durability of artificial heart valves, analyzes the important parameters of geometric modeling for artificial heart valves, and discusses the development of the corresponding modeling method, to provide reference and new ideas for the biomimetic optimization design of artificial valves.

    Release date:2023-09-28 02:17 Export PDF Favorites Scan
  • Utilization of three-dimensional printing technology for repairing skin tissue

    Three-dimensional (3D) printing is a low-cost, high-efficiency production method, which can reduce the current cost and increase the profitability of skin repair material industry nowadays, and develop products with better performance. The 3D printing technology commonly used in the preparation of skin repair materials includes fused deposition molding technology and 3D bioprinting technology. Fused deposition molding technology has the advantages of simple and light equipment, but insufficient material selection. 3D bioprinting technology has more materials to choose from, but the equipment is cumbersome and expensive. In recent years, research on both technologies has focused on the development and application of materials. This article details the principles of fused deposition modeling and 3D bioprinting, research advances in wound dressings and tissue engineering skin production, and future developments in 3D printing on skin tissue repair, including cosmetic restoration and biomimetic tissue engineering. Also, this review prospects the development of 3D printing technology in skin tissue repairment.

    Release date:2018-10-19 03:21 Export PDF Favorites Scan
  • Research progress on the role and mechanism of extracellular matrix in aortic aneurysm and dissection

    Aortic aneurysm and dissection are critical cardiovascular diseases that threaten human life and health seriously. No pharmacological treatment can effectively prevent disease progression. The imbalance of aortic wall cells and non-cellular components leads to structural or functional degeneration of the aorta, which is a prerequisite for disease occurrence. As the important non-cellular component, extracellular matrix (ECM) is crucial to maintain the aortic structure, function, and homeostasis. Abnormal production of elastin and collagen, destruction of cross-linking between elastic fibers and collagen fibers, and the imbalance of metalloproteinase and inhibitors leads to excessive degradation of ECM proteins, all of which have destroyed the structure and function of aorta. It will provide more ideas for disease prevention and treatment by learning ECM proteins and their metabolic mechanism. Here, we focus on the ECM proteins that have been reported to be involved in aortic aneurysm and dissection, and discuss the regulatory mechanism of metalloproteinase and inhibitors.

    Release date:2024-09-20 12:30 Export PDF Favorites Scan
  • Application effect evaluation of reverse digital modeling combined with three-dimensional printed disease models in standardized clinical training and teaching of pelvic tumor

    Objective To evaluated the application effect of reverse digital modeling combined with three-dimensional (3D)-printed disease models in the standardized training of orthopedic residents focusing on pelvic tumors. Methods From August 2022 to August 2023, 60 orthopedic residents from West China Hospital, Sichuan University were randomly assigned to a trial group (n=30) and a control group (n=30). The trial group received instruction using reverse digital modeling and 3D-printed pelvic tumor models, while the control group underwent traditional teaching methods. Teaching outcomes were evaluated and compared between groups through knowledge tests, practical skill assessments, and satisfaction surveys. Results Before training, there was no statistically significant difference in knowledge tests or practical skill assessments between the two groups (P>0.05). After training, the trial group showed significantly better performance than the control group in knowledge tests (90.5±5.2 vs. 78.4±6.8, P<0.05), skill assessments (92.7±4.9 vs. 81.3±6.2, P<0.05), and satisfaction surveys (9.40±1.10 vs. 7.60±1.20, P<0.05). One month after training, the trial group still showed significantly better performance than the control group in knowledge tests (88.1±6.4 vs. 72.3±7.1, P<0.05) and skill assessments (90.3±5.8 vs. 75.6±6.9, P<0.05). Conclusions Reverse digital modeling combined with 3D printing offers an intuitive and effective teaching approach that improves comprehension of pelvic tumor anatomy and strengthens clinical and technical competencies. This method significantly enhances learning outcomes in standardized residency training and holds promise for broader integration into medical education.

    Release date:2025-05-26 04:29 Export PDF Favorites Scan
  • Role of Leukocyte Activation and Inflammatory Reaction in Chronic Venous Insufficiency

    【Abstract】 Objective To discuss the role of leukocyte activation and inflammatory processes in the disease of chronic venous insufficiency (CVI). Methods The relevant literatures about the role of leukocyte activation and inflammatory reaction in CVI were reviewed. Results The role of inflammatory reaction in occurrence and development of venous diseases has been studied a lot in recent years. It was found that the leukocyte activation and inflammatory reaction are involved in the structural remodeling of venous valves and walls, leading to valvular incompetence and formation of varicose veins. Conclusion Leukocyte activation and inflammatory processes take important roles in the occurrence and progression of CVI.

    Release date:2016-09-08 11:43 Export PDF Favorites Scan
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