3.Three-dimensional element analysis of swan-like memory compressive connector for treating fractures and nonunion of humerus
Shuogui XU ; Chuncai ZHANG ; Jiacan SU ; Xiaohua LIU ; Yinong WU ; Jianguo WU ; Zhaojun XUE ; Zuquan DING ;
Academic Journal of Second Military Medical University 2000;0(10):-
Objective:To study the biomechanical basis of swan like memory compressive connector (SMC) for treating fractures and nonunions, and the facilitating effects of dynamic memorial stress of SMC for bone healing. Methods:By computer emulation and three dimensional (3D) finite element analysis, the biomechanical behavior of humeral type connector for fixing humerus was emulated and analyzed. The finite element model of humeral type connector was divided into 3 487 units. The number of nodes was 5 397. The element was a unit with 20 nodes, 4 faces. The finite element model of humerus was divided into 5 783 units, the number of nodes was 9 863. And the finite element was a 3D unit with 10 nodes, 4 faces.Results:When the connector fixated humerus, it came in for tension stress in its inner surface, and compressing stress in its outer surface. The maximum first structural major stress of metamorphosed compressive part was 224.5 MPa and -34 MPa, far less than its utmost stress and fatigue limit. The initiative memorial bone holding force for maintaining axial stability was 125.05 N, and the longitudinal initiative memorial compression force was 196 N. The stress distribution in fixed humerus was even, the stress in most nodes was positive stress. Conclusion:The SMC has good anti fatigue and reuse characters. The dynamic memorial compressive stress field is good for the stability of fixation and enhancement of bone healing.
4.Dermatofibrosarcoma: a case report
Yan LU ; Xue LI ; Meihua ZHANG ; Zhonglan SU ; Di WU ; Wenyuan ZHU ; Qinhe FAN
Chinese Journal of Dermatology 2012;45(9):670-671
A 37-year-old female was admitted to the hospital for an itching and painful subcutaneous nodule with ulceration on the extensor aspect of her left forearm for more than 6 months.The pain was severe,continuous and localized.Systemic and local treatment with antibiotics resulted in no obvious improvement.The lesion had gradually increased in size over the past 6 months and the ulcer had enlarged for 1 month.On examination,a hard infiltrative plaque measuring about 5.5 cm × 4.0 cm with a well-defined margin was seen on the extensor aspect of her left forearm,along with ulceration and some dirty discharge on the surface.The diagnosis of fibrosarcoma,grade Ⅱ was eventually made by a biopsy of the lesion,which revealed increased pigmentation in the basal layer,and tumor tissue was tightly adherent to the epidermis.Dermis and subcutaneous fat layer were infiltrated with various sizes of spindle cells with fine collagen fiber bundles between the cells.Obvious atypia and mitotic figures were easily observed in some of the cells.Immunohistochemical analysis showed moderately positive staining for fibronectin,but negative staining for human melanoma black-45 (HMB45),S100,smooth muscle actin (SMA),Melan-a,high molecular weight cytokeratin (HCK),CD34,CD68 or cytokeratin.Some diseases should be differentiated from this case,including dermatofibrosarcoma protuberans,cutaneous spindle cell squamous carcinoma,atypical fibroxanthoma,malignant fibrous histiocytoma,and so on.
5.Construction of humeral three-dimensional model and its biomechanical significance
Jiacan SU ; Chuncai ZHANG ; Baoqing YU ; Zhaojun XUE ; Jianguo WU ; Zuquan DING
Chinese Journal of Tissue Engineering Research 2005;9(10):244-245
BACKGROUND: Various therapies can be used to treat humeral fracture,but serious complications like bone disunion, etc. Are often left over. New biomechanical analytical methods are tried to be applied to provide new approaches for the functional prognosis in humeral fracture and bone disunion.OBJECTIVE: To construct humeral three-dimension model to explore its correlated biomechanical significance.DESIGN: To construct humeral three-dimension finite element model. SETTING: Department of orthopedics of a military medical university-affiliated hospital and institute for biological science and bioengineering of a university.PARTICIPANTS: The study was conducted in Shanghai Changhai Hospital and the Laboratory of Biological Science of Shanghai Tongji University. One piece of typical adult wet humerus sample was selected.INTERVENTIONS: Cross section image of each humeral layer was obtained from the selected wet humerus sample by CT scanning, and humeral three-dimensional model was constructed by large finite element analytic software ANSYS5.6.MAIN OUTCOME MEASURES: ① Biomechanical features of the constructed humeral three-dimension mode; ② Differences from clinical reality and key similarities.RESULTS: The constructed humeral three-dimensional model vividly reflected the true humeral anatomic morphology and biomechanical behavior. Its precision was judged by the comparison with CT image.CONCLUSION: The construction of humeral three-dimension finite element model provides a precise model for the researches of normal humeral mechanical behavior and the basic mechanics of internal fixation after fracture.
6.Biomechanical feature measurement of Swan-like memory compression connector
Jiacan SU ; Honghai CAO ; Ruiguan WANG ; Chuncai ZHANG ; Zhaojun XUE ; Jianguo WU ; Zuquan DING
Chinese Journal of Tissue Engineering Research 2006;10(5):182-184
BACKGROUND: The biomechanical features of Swan-like memory compression connector designed for fractures in hemerus or the parts adjacent to joints are analyzed through biomechanical calculation and experimental measurements.OBJECTIVE: To analyze the relative memory biomechanieal significance through biomechanical measurement of Swan-like memory compression connectorDESIGN: Both biomechanieal calculation and the experimental measurement were conducted for mutual supplementation and confirmation SETTING: The Orthopaedic Department of Changhai Hospital Affiliated to Second Military Medical University of Chinese PLA and the Life Science and Tissue Engineering Institute of Tongji University MATERIALS: This experiment was conducted at the laboratory of Orthopaedic Department of Changhai Hospital Affiliated to Second Military Medical University of Chinese PLA and the Life Science and Tissue Engineering Institute of Tongji University between January 2001 and May 2003.Totally 20 hemerus from adult males who died of craniocerebral injury were chosen.METHODS: Humid hemerus from the adult corpse was chosen to prepare fracture. Encircling the prescale followed by fixation of Swan-like memory compression connector, then we measured the stress produced by compression part and encircle part at fixing the fracture.MAIN OUTCOME MEASURES: ①The stress of holding part; ② the stress of the compression part RESULTS: The stress range of holding part contacting with humerus was 2.42-22.68 N, and the stress in the fracture face, which was produced by compression part, was about 13.6 Mpa.CONCLUSION: The stress of holding part of Swan-like memory compression connector is useful in fixing the fracture parts of humerus, and the stress of compression part is suitable for the healing of fracture.
7.Choice of the loading stress during the fracture fixation of humerus using Swain Memory Compression Bone Reduction Apparatus
Jiacan SU ; Ruiguan WANG ; Chuncai ZHANG ; Zhaojun XUE ; Jianguo WU ; Zuquan DING
Chinese Journal of Tissue Engineering Research 2005;9(30):234-236
BACKGROUND: During the therapy of the fracture of humerus, the main problem is the loading direction and power of the stress.OBJECTIVE: To analyze the choice of the different loading manners using Swain Memory Compression Bone Reduction Apparatus so as to provide the clinical evidence for the set position of the internal fixation apparatus, the loading direction and power during the therapy of the fracture of humerus.DESIGN: To construct the three-dimensional finite element model of the fracture of humerus with different loading manners.SETTING: Department of Orthopaedics of Changhai Hospital of Second Military Medical University of Chinese PLA; College of Life Sciences and Bioengineering of Tongji University,MATERIALS: The study was conducted during the period from January 2001 to May 2003 in the Orthopedic Laboratory of Changhai Hospital of Second Military Medical University of Chinese PLA and the laboratory of Life Science and Bioengineering Academy of Tongji University. The samples of the humerus taken from the wet adult cadavers, and the Swain Memory Compression Bone Reduction Apparatuses of the corresponding size were prepared.METHODS: The CT scanning was done on the samples of the wet humerus to obtain the cross section image of each layer of the humerus.The images were analyzed by a large-scale finite element analysis software ANSYSS.6 to construct the three-dimensional model of the humerus, Swain Memory Bone Reduction Apparatus and the fixed humerus using Swain Memory Bone Reduction Apparatus.MAIN OUTCOME MEASURES: To get the reference values for the clinical therapy through the comparison of the power endurance with different loading manners.RESULTS: The three-dimensional model of the fixed humerus using Swain Memory Bone Reduction Apparatus reflects the real anatomical configuration and the biomechanics behavior; meanwhile the status of the power endurance of humerus with different loading manners is also obtained.CONCLUSION: The three-dimensional model of the fixed humerus using Swain Memory Bone Reduction Apparatus may provide an accurate model for the basic study of the biomechanics behavior of the normal and fixed humerus after the fracture.
8.Using biomechanical calculation and experimental measurement to study the relationship between the load and the changes in the shape of the arch-dental shape memory connector
Jiacan SU ; Chuncai ZHANG ; Baoqing YU ; Zhaojun XUE ; Jianguo WU ; Zuquan DING
Chinese Journal of Tissue Engineering Research 2005;9(18):268-270
BACKGROUND: The biomechanical features of arch-dental shape memory connector designed for fractures in pelvis or the parts adjacent to joints are analyzed through biomechanical calculation and experimental measurements.OBJECTIVE: To explore the relationship between the changes in shape of arch-dental shape memory connector and the load on it.DESIGN: Both biomechanical calculation and the experimental measurement were conducted for mutual supplementation and confirmation.SETTING: The Orthopedic Department of Changhai Hospital Affiliated to the Second Military Medical University of Chinese PLA and the Life Science and Bioengineering College of Tongji University.MATERIALS:The trial was conducted from at Shanghai Changhai Hospital and Life Science Laboratory of Tongji University from April 2002 to April 2004. The subjects were arch-dental shape memory connectors.METHODS: We calculated the stress in and around the fracture face produced by arch-dental shape memory connector according to Moire principle and we also measured the changes in the shape of arch-dental shape memory connector. The relationship between load and the changes in the shape of arch-dental shape memory connector was explored.MAIN OUTCOME MEASURES: To explore whether the results of biomechanical calculation and those of the experimental measurement are consistent.RESULTS: Biomechanical calculation found that the relationship between the load (P) and the displacement(δ) in arch-dental shape memory connector was P = 13.69δ. The experimental measurement found that the load on the connector and the displacement were in a linear relationship.CONCLUSION: The relationship between the load and the displacement in arch-dental shape memory connector was linear within its elastic range and the biomechanical calculation results were consistent with the results of the experimental measurement.
9.A genetic adaptive pattern-low hemoglobin concentration in the Himalayan highlanders.
Tian-Yi WU ; Feng-Yun LIU ; Ouzhou-Loubu ; Chao-Ying CUI ; Xue-Bin QI ; Bing SU
Chinese Journal of Applied Physiology 2013;29(6):481-493
Mean hemoglobin (Hb) concentration of about 3 500 subjects derived from 17 studies of Himalayan highlanders (Tibetans, Sherpas, and Ladakhis) was compared with lowlanders (Chinese Han, Indian Tamils) lived in the Himalayas, and European climbers during Everest expeditions as well as Andean natives. The results found that Hb concentration in Himalayan highlanders was systemically lower than those reported for Andean natives and lowland immigrants. These comparative data demonstrated that a healthy native population may successfully reside at high altitude without a significant elevation in Hb, and the lower Hb levels of Himalayan highlanders than those of migrated lowlanders and Andean natives are an example of favourable adaptation over the generations. In addition, excessive polycythemia has frequently been used as a marker of chronic mountain sickness (CMS). Altitude populations who have a higher Hb concentration also have a higher incidence of CMS. The low Hb in Himalayans suggested as showing adaptation over many generations in Tibetan stock. Recent work in Tibet, suggested that Tibetans there may have adapted to high altitude as a result of evolutionary pressure selecting for genes which give an advantage at altitude. All of the population genomic and statistical analysis indicated that EPAS1 and EGLN1 are mostly likely responsible for high altitude adaptation and closely related to low Hb concentration in Tibetans. These data supported the hypothesis that Himalayan highlanders have evolved a genetically different erythropoietic response to chronic hypoxia by virtue of their much longer exposure to high altitude.
Adaptation, Physiological
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Altitude
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Asian Continental Ancestry Group
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genetics
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Basic Helix-Loop-Helix Transcription Factors
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genetics
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Evolution, Molecular
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Hemoglobins
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genetics
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Humans
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Hypoxia-Inducible Factor-Proline Dioxygenases
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genetics
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Tibet
10.Relationship between high sensitive C-reactive protein and stroke subtype according to Chinese Ischemic Stroke Subclassification criteria in patients with acute cerebral infarction
Xinhong XUE ; Lifeng QI ; Hong LIU ; Haixin YANG ; Jiangli SU ; Shuhui WU
Chinese Journal of General Practitioners 2014;13(9):764-766
By analyzing the clinical data of 216 cases of acute cerebral infarction (ACI) from 2012 January to 2013 June retrospectively,we found that the serum levels of high sensitive C-reactive protein (hs-CRP) in patients were significantly higher than those in 186 controls (P <0.01).The degree of neural function defect in ACI patients was assessed by the National Institutes of Health Stroke Scale (NIHSS) score.The hs-CRP level of the patients with NIHSS score > 8 were higher than that in those with NIHSS score ≤8 (P < 0.05).The hs-CRP level of patients of large artery atherosclerosis were (6.32 ± 4.12) mg/L and the positive rate of hs-CRP was 85.7% (84/98).All were respectively higher than those in patients of penetrating artery disease [(1.97 ±0.86) mg/L,7/71],cardiogenic stroke [(3.70 ± 2.76) mg/L,14/24],undetermined etiology [(3.43 ± 3.52) mg/L,5/11] and other etiologies [(3.41 ± 3.25) mg/L,5/12] (all P < 0.05).Logistic regression analysis was performed for the risk factors of ACI.The correlative factors of ACI included hypertension,diabetes mellitus,atrial fibrillation,smoking,total cholesterol,homocysteine and high sensitive C-reactive protein (OR =1.56,1.19,1.23,1.17,3.08,1.34,1.25,all P < 0.01).The serum levels of hs-CRP increased significantly in ACI patients and were correlated with the degree of neural function defect.