1.Determination of contact force at facet joint with different sagittal orientation under shearing loads:a finite element analysis
Yaosheng LIU ; Qixin CHEN ; Shubin LIU
Orthopedic Journal of China 2008;16(10):748-752
[Objective] The efleet of sagittal orientations of articular facet on the contact force and contact regions of a lumbar spine segment was evaluated.[Methods] [Results]Three-dimensional geometrical and mechanical accurate finite element models of the lumbar L4、5 motion segment representing three sagittal-orientations articular facet were generated and invalidated by an effective CAD method.Contact force and contact regions of the articular facets of three finite element models were predicted under the pure shearing loads.[Result] Under anterior shear condition,the contact force on the facet decreased with the increase of sagittal 0rientation of articular facet.however.in posterior shear load,the contact force on the facet increased with the increase of sagittal orientation.Meanwhile,under both pure shear loading,the percentages of the sagittal and the transversal components are increased with the dectease of the sagittal angle.However,under the salne load condition,there are no difference between the contact regions of the three models with different facet joint angle.[Conclusion]The spatial orientation and geometric forms of the coronal facet articular surfaces are more effective in restricting motion in transversal and sagittal planes while assuming a minor role in resisting axial force or motion than sagittal facet articular surface.It Was presumed that anterior shear force play a more prominent contribution on the degeneration of the facet joint with coronal articular surface compared with posterior shear force.
2.Proximal femoral nailversus hemiarthroplasty for unstable intertrochanteric fractures in osteoporotic patients
Liping CHEN ; Fusheng LIU ; Yaosheng YANG
Chinese Journal of Tissue Engineering Research 2017;21(27):4277-4282
BACKGROUND: Both proximal femoral nail and hemiarthroplasty have been applied in the treatment of unstable intertrochanteric fractures in osteoporotic patients. However, which has better curative efficacy is still under discussion.OBJECTIVE: To investigate the clinical effectiveness of proximal femoral nail versus hemiarthroplasty in the treatment of unstable intertrochanteric fracture in osteoporotic patients.METHODS: Sixty-seven patients diagnosised with unstable intertrochanteric fractures and osteoporosis were selected,and were randomly divided into two groups, followed by treated with hemiarthroplasty (group 1, n=35)) and proximal femoral nail (group 2, n=32), respectively. The operation time, intraoperative blood loss, length of incision, postoperative time in bed, hospitalization time and complications were recorded and compared between two groups. Harris hip scores were used to evaluate the preoperative and postoperative hip function.RESULTS AND CONCLUSION: (1) In the group 1, the operation time, intraoperative blood loss and length of incision were more than those in the group 1, and the postoperative time in bed was less than that in the group 2 (P < 0.05).However, the healing and hospitalization time did not differ significantly between two groups (P > 0.05). (2) No significant difference was observed in the excellent and good rate in Harris hip scores between two groups at the last follow-up (P >0.05). The postoperative pain scores in the group 1 were significantly superior to those in the group 2 (P < 0.05). (3)There were 1 case of delayed union and 1 case of lateral hip appearing with pain in the group 2. At the last follow-up, all patients healed completely, and no prosthesis dislocation, loosening or infection was found. (4) To condude,hemiarthroplasty provides early functional recovery and fewer complications, but with much surgical trauma. Proximal femoral nail shows similar treatment outcomes with hemiarthroplasty; therefore, it is a kind of alternative treatment strategy for unstable intertrochanteric fractures.
3.Histopathological changes of sequestration-type lumbar herniated disc
Qixin CHEN ; Yaosheng LIU ; Fangcai LI
Chinese Journal of Orthopaedics 2001;0(08):-
Objective To demonstrate the histopathological changes of sequestration-type herniated disc, and investigate the related factors of its absorption. Methods 39 tissue samples were surgically removed from 37 patients with sequestration-type lumbar disc herniation. All the tissues were performed with HE stain and immunohistochemical study. In HE stain, the origin of tissue was identified; in immunohistochemical study, anti-CD34 antibody was used for detecting the vascular endothelial cells, and anti-CD68 for macrophages. The sequestration-type lumbar disc was divided into 3 groups according to the content of nucleus pulposus: nucleus pulposus group, nucleus pulposus contained group and non-nucleus pulposus group. The correlation between the extent of angiogenesis and macrophage infiltration and the factor of age, disease duration, origin of sequestrated tissue and imaging features was studied. Results 62% (24/39) of the sequestrated tissues were mainly originated from nucleus pulposus. Granulation tissue with many macrophages around new blood vessels was found in 92%(36/39) of the sequestrated tissues. There was a significant difference of the extent of angiogenesis and macrophage infiltration among these 3 groups in terms of the content of nucleus pulposus group(F=5.663, P=0.008; F=3.604, P=0.038). There was no significant correlation between the extent of angiogenesis and macrophage infiltration and age or disease duration, whereas, a positive significant correlation was found for the size of sequestrated tissue (r=0.342, P=0.033; r=0.440, P=0.005). Furthermore, the extent of angiogenesis and macrophage infiltration was significant when the relative signal intensity of sequestrated tissue on MRI was in 0.30-0.72. Conclusion The origin of sequestration-type herniated disc is mainly from nucleus pulposus, and most of the sequestration tissue can be absorbed in different extent. The extent of spontaneous absorption was mainly depended on the origin of the sequestration tissue, but not the age or disease duration. Predominant absorption is found in bigger size of the sequestration tissue and their relative signal intensity on MRI being 0.30-0.72.
4.Contribution of sagittal orientation of facet joints and disc degeneration to degenerative spondylolisthesis in lumbar spine:A finite element research
Yaosheng LIU ; Qixin CHEN ; Shenghui LIAO
International Journal of Biomedical Engineering 2006;0(05):-
Objective To research the connection between the sagittal orientation of facet joints and disc degeneration in lumbar spine and to investigate the contribution of which to development the degenerative spondylolisthesis. Methods A new effective CAD method was used to accurately establish 9 finite element models(FEM)which were assembled respectively with facet-joint angle 65?, 45?, 25?, with normal disc, light degenerative disc and severe degenerative disc. The biomechanical parameters of 9 finite element models were measured under axial compressive load within physiological range. Results Compared with FEMs with facet-joint angle 45? and 25?, anterior displacement of L4 vertebra in FEMs with facet-joint angle 65? was increased, where the maximum von Mises stresses on facet surface, isthmus and the contact force on facet surface in horizontal orientation were obviously increased. Meanwhile, FEMs with facet-joint angle 65? showed a decrease in end-plate bulge and an increase in stress of annular matrix. The stiffness in light degenerative disc FEMs was reduced and the von Mises stresses on facet surface and isthmus was slightly increased compared with the normal disc FEMs. Among all, the FEM with facet-joint angle 65? combined with light degenerative disc showed the poorest resisting anterior shear force. Conclusion Sagittal orientation of facet joints is not only the primary inducement of the degenerative spondylolisthesis but the secondary pathological change of remodeling of the facet-joints induced by the regional stress change. The inherent instability of lumbar motion segment of sagittal orientation of facet joints is influenced by the lumbar disc degeneration. The lumbar disc degeneration has no manifested contribution to the aggravation of the sagittal orientation of facet joints.
5.Genetic cloning and sequence analysis of farnesyl pyrophosphate synthase in Panax notoginseng
Li CHEN ; Xiuwan LAN ; Shen LI ; Hua ZHU ; Yaosheng WU
Chinese Traditional and Herbal Drugs 1994;0(07):-
Objective To clone and sequence the cDNA encoding farnesyl pyrophosphate synthase(FPS) from Panax notoginseng.Methods The cDNA,encoding FPS in P.notoginseng,was amplified by RACE strategy with the total RNA of root as the template.The fragment of FPS was cloned and sequenced.Results The analysis results revealed that the full-length cDNA had(1 409) bp with an open reading frame encoding 343 amino acids of protein.The FPS sequence had 95%,87%,and 86% amino acid sequence homology to the FPS sequence of Centella asiatica,Parthenium argentatum,and Artemisia annua,respectively. Conclusion The cDNA encoding FPS from P. notoginseng is cloned and reported.This works provide a foundation for exploring the mechanism of saponins biosynthesis and application to the other medical plants.
6.An Accurately Represented Finite Element Model of Lumbar Motion Segment
Yaosheng LIU ; Qixin CHEN ; Fangcai LI ; Xiaojun TANG ; Jie FANG ; Shenghui LIAO ; Shice YU
Space Medicine & Medical Engineering 2007;14(2):79-86
Objective To construct a detailed, 3-dimensional, anatomically accurate finite element (FE) model of lumbar L4-L5 segment from CT data with a new kind of computer aided design (CAD) method. Methods A modified "no-seed region segmentation" was done to extract the interest region in the CT scan images and produce a binary image. "Best cross-section planes" accounting for the preferential direction dictated by lumbar spine were placed on the initial iso-surface model, forming a "non-regular piecewise subspace". This subspace and the embedded iso-surface mode were transformed by local affine transforms to a "regular subspace", in which a surface mesh of high quality was generated quickly. Finally a reverse transform procedure was employed to recover the shape feature of the lumbar surface mesh of lumbar L4-L5 in the original 3-dimensional space, which was then imported into ANSYS for the 3-dimensional FE mesh construction. Results All complicated anatomical features of the L4-L5 segment were explicitly represented in the unprecedented finite element model. The predicted results for compression, flexion and extension correlated well with experimental data under similar loading configurations. Conclusion The presented CAD method containing advanced algorithm implements fast and accurate simulation of such complicated geometry with fine mesh representation for lumbar FE analysis.
7.Screening Technology for Traditional Chinese Medicine New Drug and Practice
Yaosheng TU ; Dongmei SUN ; Yuxing CHEN ; Xiaohui ZENG ; Dane HUANG ; Dengping TAN
World Science and Technology-Modernization of Traditional Chinese Medicine 2014;(8):1696-1702
This article focused on summarization of the available new screening technology for traditional Chinese medicine (TCM) new drug, including high throughput screening (HTS), biological chip, molecular biological chro-matography, high content screening (HCS), network pharmacology, proteomics, and computer-aided drug design (CADD). And in this review, one example that we applied CADD technology (such as molecular docking, pharma-cophore and molecular similarity) in lipid-lowering TCM new drug development was given. Based on the mechanism of lipid metabolism, CADD technology provided a good method on the prescription optimization and mechanism study. In addition, TCM new drug development proposal which displayed in this paper may provide a useful strategy for screening of TCM new drug.
8.Multiband mucosectomy in treatment of early cancer and precancerous lesions of esophagogastric junction
Bin DENG ; Dacheng WU ; Mei WANG ; Yaosheng CHEN ; Yuanzhi WANG ; Jian WU ; Yanbing DING
Chinese Journal of General Practitioners 2014;13(12):1014-1016
Eighteen patients with early cancer and precancerous lesions of esophagogastric junction underwent multiband mucosectomy (MBM) in Yangzhou First People's Hospital from January 2013 to February 2014.The clinicopathological data of patients were analyzed retrospectively and the short-term efficacy and safety of MBM were evaluated.Operations were successful in all 18 cases.The mean operative time was 35.8 min.Intraoperative bleeding occurred in 3 cases and successfully managed by endoscopic hemostasis.Small perforation occurred in 1 patient and was closed by metal clips.Pathological examination showed mucosal cancer in 5 cases,high-grade intraepithelial neoplasia in 8 cases and low-grade intraepithelial neoplasia in 5 cases.No relapse of cancer was found during follow-up.Results indicate that MBM is an effective and safe method in treatment of early cancer and precancerous lesions in the esophagogastric junction.
9.Research on a new method to trigger ventilator based on electromyogram.
Yaosheng LU ; Ying XIAN ; Jiongfeng CHEN ; Zeguang ZHENG
Journal of Biomedical Engineering 2009;26(6):1222-1254
In order to improve synchrony between a ventilator and its patient, a new method for triggering a ventilator based on diaphragmatic electromyogram (EMG) is introduced. The methods to extract and process diaphragmatic EMG signals are studied. It has been shown that the characteristic parameters of a respiration activity, such as inspiratory beginning point, expiratory beginning point and respiration period, can be detected from diaphragmatic EMG envelop instead of traditional flux curve. A new parameter, designated as diaphragmatic "Intensity of EMG" for short "IEMG", is defined. Repeat respiration tests have disclosed that there is relatively high correlation between the diaphragmatic IEMG curve and its corresponding cubage curve. These results primarily demonstrate that the new synchronization method may be feasible.
Diaphragm
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physiology
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Electromyography
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Humans
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Positive-Pressure Respiration
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methods
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Respiration
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Respiration, Artificial
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methods
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Respiratory Insufficiency
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therapy
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Respiratory Muscles
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physiology
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Work of Breathing
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physiology
10.Does bariatric surgery decrease the risk of obesity-related tumor: a meta-analysis.
Songxin XU ; Bin DENG ; Yaosheng CHEN ; Yanbing DING ; Zishan XU
Chinese Journal of Gastrointestinal Surgery 2015;18(11):1144-1148
OBJECTIVETo explore whether bariatric surgery can decrease the incidence of obesity-related tumors in obesity patients.
METHODSRelevant studies comparing the incidence of obesity-related tumors in obesity patients between bariatric surgery and non- bariatric surgery were identified by search of PubMed, Medline, EBSCO, High Wire Press, OVID, EMbase, China hownet (CNKI) and Wanfang databases since the self-built database. In strict accordance with the standard after the screening, literature quality and extracted data were evaluated. Review manager 5.2 software was used to perform meta-analysis and sensitivity analysis. Inverted funnel chart was used to investigate the publication bias.
RESULTSFive articles including 108 954 patients were enrolled in the analysis. Among them, 26 218 cases were bariatric surgery group, and 82 736 cases of non-surgical weight loss were the control group. Meta analysis showed that bariatric surgery could obviously decrease the incidence of postoperative obesity-related tumor(RR=0.60, 95% CI:0.45-0.80, P=0.0005). Subgroup analysis showed that cancer risk difference of obesity-related tumor in male patients was not significant between two group, while the postoperative incidence of obesity-related tumor of female patients in bariatric surgery group was significantly lower compared to those female patients in control group(RR=0.68, 95% CI:0.61-0.77, P<0.01). During follow-up of 1 to 10 years, the incidence of obesity-related tumor in bariatric surgery group was significantly lower than that in control group(P<0.05). When follow-up was more than 10 years, the incidence of obesity-related tumors was similar between two groups(P=0.70).
CONCLUSIONBariatric surgery can decrease the overall risk of obesity-related cancer, especially for female patients, but with the prolongation of time, such effect of bariatric surgery is not obvious.