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1.
BMC Urol ; 24(1): 41, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365727

RESUMO

Incarceration of the appendix within a femoral hernia is a rare condition of abdominal wall hernia about 0.1 to 0.5% in reported femoral hernia [1]. We report a case of a 56-year-old female whose appendix was trapped in the right femoral canal. There are few reports in the literature on entrapment of the appendix within a femoral hernia. The management of this condition includes antibiotics, drainage appendectomy, hernioplasty and mesh repair.


Assuntos
Apendicite , Hérnia Femoral , Hérnia Inguinal , Feminino , Humanos , Pessoa de Meia-Idade , Apendicectomia , Apendicite/complicações , Apendicite/cirurgia , Hérnia Femoral/complicações , Hérnia Femoral/cirurgia , Hérnia Inguinal/cirurgia , Herniorrafia , Doença Aguda
2.
Zhongguo Gu Shang ; 35(8): 736-9, 2022 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-35979766

RESUMO

OBJECTIVE: To explore the effects of different administration methods of tranexamic acid(TXA) on the perioperative blood loss, hidden blood loss, transfusion rate and adverse reactions in lumbar spinal decompression and fusion. METHODS: Sixty patients who received lumbar spinal canal decompression and fusion from July 2019 to July 2020 were enrolled and divided into observation group and control group, with 30 cases in each group. The observation group was given 2 g TXA orally at 2 hours before operation, control group was given 1 g TXA for 5-10 min before skin incision and 6 hours after operation intravenously. The intraoperative blood loss, postoperative drainage, total blood loss, hidden blood loss, drainage tube removal time, blood transfusion rate, venous thrombosis rate, adverse event rate were recorded respectively. The changes of hemoglobin(Hb) and hematocrit (HCT) were observed before operation and 1, 3 days after operation. RESULTS: Hb and HCT at 1 and 3 days after operation were significantly improved compared with those before operation(P<0.01). However, there was no significant difference between the groups(P>0.05). There were no significant difference in amount of blood loss, postoperative drainage, total blood loss, intraoperative blood loss, hidden blood loss, postoperative drainage time, and blood transfusion rate between two groups (P>0.05). There were no venous thrombosis and adverse events occurred in both groups. CONCLUSION: During the perioperative period of lumbar spinal decompression and fusion, oral TXA and intravenous TXA have the same effect in reducing perioperative blood loss and are safe and reliable. It is recommended that oral TXA be used to save medical costs and convenience.


Assuntos
Antifibrinolíticos , Fusão Vertebral , Ácido Tranexâmico , Trombose Venosa , Antifibrinolíticos/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Descompressão , Humanos , Hemorragia Pós-Operatória , Canal Medular , Fusão Vertebral/métodos , Ácido Tranexâmico/uso terapêutico , Trombose Venosa/etiologia
3.
Mol Med Rep ; 15(4): 2280-2288, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28260107

RESUMO

The aim of the present study was to investigate the role of myristicin (Myr; 1­allyl­5­methoxy­3,4­methylenedioxybenzene), an active aromatic compound isolated from nutmeg, carrot, basil, cinnamon and parsley, in hypoxia­induced apoptosis in rat dorsal root ganglion (DRG) neurons. It was observed that Myr significantly enhanced cell viability in hypoxia­induced DRG neurons in a dose­dependent manner; the optimal concentration of Myr was 50 µM. Furthermore, Myr reduced the percentage of deoxynucleotidyl transferase­mediated dUTP nick end­labeling­positive neuronal cells and influenced the expression of the pro­apoptotic gene B­cell lymphoma 2 (Bcl­2) associated X protein, the apoptosis protease cleaved caspase­3 and the anti­apoptotic gene Bcl­2, in the hypoxia­induced group. In addition, Myr protected against hypoxic injury in DRG neurons by inhibiting malondialdehyde and lactate dehydrogenase, however upregulating superoxide dismutase and glutathione peroxidase. Myr reduced the expression of endoplasmic reticulum stress (ERS) markers, including CCAAT/enhancer­binding protein­homologous protein, glucose­related protein 78 and cleaved caspase­12 in the hypoxia­induced group. To the best of our knowledge, this is the first demonstration of the activity of Myr against hypoxia­induced apoptosis in rat DRG neurons via inhibition of the ERS pathway.


Assuntos
Apoptose/efeitos dos fármacos , Compostos de Benzil/farmacologia , Hipóxia Celular/efeitos dos fármacos , Dioxolanos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Gânglios Espinais/citologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Pirogalol/análogos & derivados , Derivados de Alilbenzenos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Gânglios Espinais/efeitos dos fármacos , Hipóxia/complicações , Hipóxia/tratamento farmacológico , Hipóxia/metabolismo , Masculino , Neurônios/citologia , Neurônios/metabolismo , Pirogalol/farmacologia , Ratos , Ratos Sprague-Dawley
4.
Bioorg Med Chem ; 21(5): 1064-73, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23380475

RESUMO

A series of aloe-emodin derivatives were designed, synthesized and evaluated as acetylcholinesterase inhibitors. Most of the new prepared compounds showed remarkable acetylcholinesterase inhibitory activities. Among them, the compound 1-((4,5-dihydroxy-9,10-dioxo-9,10-dihydroanthracen-2-yl) methyl) pyridin-1-ium chloride (C3) which has a pyridinium substituent possessed the best inhibitory activity of acetylcholinesterase (IC(50)=0.09 µM). The docking study performed with AUTODOCK demonstrated that C3 could interact with the catalytic active site (CAS) and the peripheral anionic site (PAS) of acetylcholinesterase.


Assuntos
Acetilcolinesterase/química , Antraquinonas/química , Inibidores da Colinesterase/síntese química , Acetilcolinesterase/metabolismo , Antraquinonas/síntese química , Antraquinonas/metabolismo , Sítios de Ligação , Domínio Catalítico , Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Avaliação Pré-Clínica de Medicamentos , Cinética , Simulação de Acoplamento Molecular , Ligação Proteica , Relação Estrutura-Atividade , Tacrina/química , Tacrina/metabolismo
5.
Chin Med J (Engl) ; 125(22): 4055-60, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23158142

RESUMO

BACKGROUND: This study aimed to investigate the effect of pcDNA3.1-vascular endothelial growth factor (VEGF)165 vector on vertebral cartilage endplate vascular buds and intervertebral discs. METHODS: Rabbits were randomly assigned to the control and experimental groups with 10 in each. In the experimental group, we anesthetized the rabbits and exposed the front vertebral body. Using the mark of the longitudinal ossature of the front vertebral body of the lumbar vertebrae, we advanced a needle at the central point of the front fourth and fifth lumbar intervertebral discs and injected 20 µl pcDNA3.1-VEGF165. Similarly, in the control group, we injected 20 µl pcDNA3.1. At 4 and 8 weeks post-injection, we examined the changes of the vertebral cartilage endplate using X-ray radiograph, histology, and scanning electron microscopy. RESULTS: The vertebral cartilage endplate calcification and degeneration in the experimental group were less than those in the control group at 8 weeks post-operation. The average number and diameter of vascular buds obviously increased in the experimental group at 4 and 8 weeks post-operation. The number of vascular buds and the diameter in the region of the inner annulus increased when compared to those in the area near the nucleus pulposus. CONCLUSIONS: The pcDNA3.1-VEGF165 plasmid can increase the average number and diameter of vascular buds and decelerate intervertebral disc degeneration.


Assuntos
Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Feminino , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/metabolismo , Deslocamento do Disco Intervertebral/genética , Deslocamento do Disco Intervertebral/metabolismo , Masculino , Microscopia Eletrônica de Varredura , Plasmídeos/genética , Coelhos , Fator A de Crescimento do Endotélio Vascular/genética
6.
Spine (Phila Pa 1976) ; 37(14): 1192-7, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22695244

RESUMO

STUDY DESIGN: Intermittent Cyclic Mechanical Tension (ICMT) was applied to end plate chondrocytes by using an FX-4000T Flexercell Tension Plus unit (Flexcell International Corporation, Hillsborough, NC). Changes of end plate chondrocytes were observed after ICMT stimulation. OBJECTIVE: To investigate the relationship between mechanical stimulation and calcification of end plate chondrocytes. SUMMARY OF BACKGROUND DATA: Previous study showed that end plate calcification was related to mechanical stress, but there was no clear evidence to indicate whether or not mechanical stimulation could induce calcification of end plate chondrocytes in vitro. METHODS: Rat end plate chondrocytes were cultured and ICMT (strain at 0.5 Hz sinusoidal curve at 10% elongation) was applied for 25 days, 4 hours a day and continued to culture for 5 days. End plate chondrocytes were incubated for 12 hours in the presence or absence of 10 ng/mL of transforming growth factor-ß1 (TGF-ß1) (prepared from a stock solution at 10 µg/mL in 2 mM citric acid containing 2 mg/mL bovine serum albumin) in MEM/F-12 containing a final concentration of 1% FCS. End plate chondrocytes calcification was stained by alizarin red S (AR-S). End plate chondrocytes viability was examined by LIVE/DEAD viability/cytotoxicity kit (Invitrogen, Carlsbad, CA). Related gene expression was examined by reverse transcription-polymerase chain reaction and Western blot. RESULTS: LIVE/DEAD assay verified that the nonloading (NC) group and the ICMT group end plate chondrocytes remained adherent, with no change in viability after the application of ICMT. Alizarin red staining showed that ICMT induced the calcification of end plate chondrocytes. Real-time reverse transcription-polymerase chain reaction showed that mRNA expression of endogenous TGF-ß1 decreased and mRNA expression of type I, type X, osteocalcin and osteopontin increased after ICMT. The ankh gene expression of both mRNA and protein levels decreased in the ICMT stimulation. The ankh gene expression of both mRNA and protein levels increased in TGF-ß1 stimulation. Compared with NC group, the alkaline phosphatase activities significantly increased in ICMT group. CONCLUSION: Our results directly showed that ICMT induced the calcification and downregulation of ankh gene expression of end plate chondrocytes, which may be caused by the endogenous TGF-ß1.


Assuntos
Calcificação Fisiológica , Condrócitos/metabolismo , Regulação da Expressão Gênica , Proteínas de Transporte de Fosfato/genética , Animais , Western Blotting , Sobrevivência Celular , Células Cultivadas , Condrócitos/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo X/genética , Colágeno Tipo X/metabolismo , Regulação para Baixo/efeitos dos fármacos , Lâmina de Crescimento/citologia , Lâmina de Crescimento/efeitos dos fármacos , Lâmina de Crescimento/metabolismo , Osteocalcina/genética , Osteocalcina/metabolismo , Osteopontina/genética , Osteopontina/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estresse Mecânico , Fatores de Tempo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/farmacologia
7.
Zhonghua Yi Xue Za Zhi ; 92(7): 491-5, 2012 Feb 21.
Artigo em Chinês | MEDLINE | ID: mdl-22490974

RESUMO

OBJECTIVE: To directly inject recombinant pcDNA3.1-VEGF165 plasmid into degeneration intervertebral disc and explore its effects on vascular buds of vertebral cartilage endplate and intervertebral disc in rabbits. METHODS: Rabbits were randomly assigned into the experimental and control groups (n = 10 each). For the experimental group, the animals were anesthetized and the front vertebral body exposed. With the longitudinal ossature of front vertebral body of lumbar vertebrae as a mark, a needle was inserted at the central point of the front fourth and fifth lumbar intervertebral disc and 20 µl pcDNA3.1-VEGF165 injected. For the control group, 20 µl pcDNA3.1 was injected. At Weeks 4 and 8 post-injection, the changes of vertebral cartilage endplate were monitored by radiograph, histology and scanning electron microscopy. RESULTS: The vertebral cartilage endplate calcification and degeneration in the experimental group were less pronounced than that in the control group at Week 8 post-operation. The average number and diameter of vascular buds obviously increased in the experimental group at Weeks 4 and 8 post-operation. The number and diameter of vascular buds in the region of inner annulus increased compared with those in the area near nucleus pulposus. CONCLUSION: The pcDNA3.1-VEGF165 plasmid may promote the vascular buds of vertebral cartilage endplate by increasing their average number and diameter and arresting the intervertebral disc degeneration.


Assuntos
Cartilagem/efeitos dos fármacos , Disco Intervertebral/irrigação sanguínea , Placa Motora/irrigação sanguínea , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Disco Intervertebral/efeitos dos fármacos , Degeneração do Disco Intervertebral/patologia , Placa Motora/efeitos dos fármacos , Plasmídeos , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética
8.
Orthop Surg ; 3(4): 247-52, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22021141

RESUMO

OBJECTIVE: To comparatively assess the clinical outcome of modified unilateral percutaneous vertebroplasty for the treatment of osteoporotic vertebral compression fractures. METHODS: The clinical outcome and incidence of cement extrusion in a consecutive group of 70 patients at our institution between December 2005 and December 2008 was retrospectively reviewed. Thirty-five patients were randomly distributed to modified percutaneous vertebroplasty (Group A) and 35 to traditional percutaneous vertebroplasty (Group B). A visual analog scale (VAS) was used on the first post-operative day and 1 year later to assess the severity of pain before and after vertebroplasty. The incidence of cement extrusion on CT scan was also compared between the two groups. RESULTS: The treatment was successful in all seventy patients. The incidence of cement extrusion was 14.29% (5/35 patients) in group A, and 37.12% (13/35 patients) in group B, this difference being statistically significant (P < 0.05). No patients had serious complications. Complete pain relief was achieved in 50 patients, and significant relief in the other 20 (20/70 patients). There was no statistically significant difference between Groups A and B. CONCLUSION: Modified percutaneous vertebroplasty enhances the accuracy of cement injection into the center of the vertebral body, increasing the safety of the procedure with no increase in cost. It is a safer and more easily performed technique for treating patients with osteoporotic vertebral compression fractures than traditional percutaneous vertebroplasty.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas por Compressão/cirurgia , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vertebroplastia/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluoroscopia/métodos , Seguimentos , Fixação Interna de Fraturas/efeitos adversos , Consolidação da Fratura/fisiologia , Fraturas por Compressão/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fraturas por Osteoporose/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Medição de Risco , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vertebroplastia/efeitos adversos
9.
Mol Med Rep ; 4(5): 831-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21674130

RESUMO

We investigated the effects of mechanical strain on the progressive ankylosis (ANK) gene and extracellular nucleotide phosphatase/phosphodiesterase (ENPP)1 mRNA expression and TGF-ß1 protein expression in rat endplate chondrocytes in vitro. Endplate chondrocytes were isolated and cultured in vitro. Following identification with toluidine blue and immunocytochemical staining, chondrocytes were subjected to 10% elongation with various frequencies (0.5, 1, 1.5 and 2 Hz) using a Flexercell Tension Plus system at various intervals (3, 6, 12, 24, 36 and 48 h). As a control, cells that had been cultured statically on the same type of plate but were not subjected to stretch were also observed. Real-time reverse transcription-polymerase chain reaction and the enzyme-linked immunosorbent assay were used to study the effects of mechanical strain on ANK and ENPP1 mRNA expression and TGF-ß1 concentration in the supernatant, respectively. Following treatment, the shape of the chondrocytes displayed a significant change from the original polygon to a typical spindle cell morphology; and the arrangement of the cells exhibited a change from a haphazard arrangement to an alignment with a certain direction. In the 0.5 Hz, 24-h group, the ANK gene expression was significantly increased compared to the control group (P<0.05); whereas in the other groups, the ANK and ENPP1 expression levels were reduced. With the increased frequencies in the 24-h group, the ANK gene expression gradually reduced. Changes in the expression of ANK and ENPP1 followed similar trends. TGF-ß1 in the supernatant increased gradually in each frequency group, with a clear increase in the 0.5 Hz group. We conclude that various frequencies of mechanical strain can affect the expression of ANK, ENPP1 and endogenous TGF-ß1 in endplate chondrocytes. Our results indicate that 0.5 Hz, 24 h may be the optimal stimulation condition to prevent calcification occurrence and to maintain the function of endplate chondrocytes.


Assuntos
Condrócitos/enzimologia , Placa Motora/citologia , Proteínas de Transporte de Fosfato/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Pirofosfatases/metabolismo , Estresse Mecânico , Fator de Crescimento Transformador beta1/metabolismo , Animais , Forma Celular , Células Cultivadas , Condrócitos/citologia , Regulação da Expressão Gênica , Masculino , Fenótipo , Proteínas de Transporte de Fosfato/genética , Diester Fosfórico Hidrolases/genética , Pirofosfatases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Frações Subcelulares/metabolismo
10.
Zhonghua Yi Xue Za Zhi ; 90(17): 1192-6, 2010 May 04.
Artigo em Chinês | MEDLINE | ID: mdl-20646567

RESUMO

OBJECTIVE: To observe the expression change of ANK protein in normal and degenerative vertebral endplate chondrocytes and explore the correlation between ANK gene expression and intervertebral disc degeneration. METHODS: Cartilaginous endplates of 45 patients were divided into experiment group (28 with cervical spondylotic myelopathy including 17 males and 11 females) and control group (17 with fracture or dislocation of cervical spine including 10 males and 7 females). The MRI examinations revealed that all the endplate in control group were grade 0 and grade I-III in experiment group according to Miller's classification. Pathological examination demonstrated that intervertebral discs were grade I in control group and grade III-V in experiment group according to Thompson's classification. The morphological appearances and calcification of cartilaginous endplates were observed by HE and Von kossa staining. Immunohistochemical SABC staining, RT-PCR and Western blot were used to detect the ANK mRNA and protein expression in chondrocytes. RESULTS: More calcium deposit could be observed in the experiment group than in the control group by Von kossa staining. ANKH protein was found positive in cell membrane of chondrocytes. Compared with chondrocytes of control group, the expression of ANK mRNA in experiment group markedly decreased (P < 0.05). And the level of ANK protein expression decreased too (P < 0.05). CONCLUSION: Following the degeneration of cartilaginous endplate, the intervertebral disc degeneration worsened and the expression level of ANK decreased in vertebral endplate chondrocytes. Also calcification is positively correlated with the degree of intervertebral disc degeneration. Modulating the expression of ANK in endplate chondrocytes may be a new approach to treat the degeneration of intervertebral disc.


Assuntos
Vértebras Cervicais/metabolismo , Condrócitos/metabolismo , Placa Motora/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Adulto , Senescência Celular , Vértebras Cervicais/patologia , Condrócitos/patologia , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Placa Motora/patologia
11.
Zhonghua Yi Xue Za Zhi ; 90(1): 19-23, 2010 Jan 05.
Artigo em Chinês | MEDLINE | ID: mdl-20356519

RESUMO

OBJECTIVE: To collect the radiological data of the presacral space for axial lumbosacral interbody fusion (AxiaLIF) and to provide theoretic rationales for research work and clinical application of AxiaLIF in China. METHODS: The distance between inner margin of bilateral anterior sacral foramina at the level of S1 was measured radiographically. The distance between iliac vessels and the midline at the level of S1 was measured on enhanced computed tomography (enhanced-CT). The minimum distances between mesorectum and each sacral level or the center of each sacral vertebra were measured on the median sagittal plane of magnetic resonance imaging in order to measure the lengths of relevant instrumentation and fusion device. RESULTS: The distance between inner margin of bilateral anterior sacral foramina at the level of S1 was found to be 34.7 + or - 3.5 and 32.2 + or - 3.0 mm in Chinese males and females respectively (P < 0.05). There was no statistical significance between the design lengths of sleeve and fusion device. The nearest vessel from sacral intervertebral space at the level of S1 was found to be the bilateral internal iliac vein on enhanced-CT with a distance of 57.6 + or - 5.2 and 70.0 + or - 9.1 mm in males and females respectively (P < 0.05). The distance from mesorectum to the center of vertebral body of S2-S5 was found to be statistically significant between males and females (P < 0.05). CONCLUSION: It is feasible to design suitable instrumentation and fusion device for the Chinese. And a safe operating zone has been designated.


Assuntos
Região Lombossacral/diagnóstico por imagem , Fusão Vertebral/métodos , Tomografia Computadorizada Espiral , Adolescente , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Zhonghua Yi Xue Za Zhi ; 90(3): 153-6, 2010 Jan 19.
Artigo em Chinês | MEDLINE | ID: mdl-20356547

RESUMO

OBJECTIVE: To establish a 3D finite element model of L5/S1 motion segment with percutaneous axial lumbosacral interbody fusion (AxiaLIF) screw and conduct a preliminary analysis of biomechanical stress. METHODS: The titanium screw was implanted in L5 and S1 vertebral body. Solid model was established by CAD software according to the actual dimensions of screw. Then computer graphics were obtained from iges format and imported into the finite element analysis software to establish the finite element model. With the aid of Mechanical Virtual Human of China, a 3D finite element model of L5/S1 motion segment with AxiaLIF screw was established. Vertical compression, torque moment and bending moment were loaded respectively on the upper surface of L5 vertebrae to simulate the load stress in human body. Stress distribution of screw was obtained. RESULTS: Generally stress values were relatively low. Peak stresses of screw under three loading conditions were 175.334 Mpa, 183.765 Mpa and 146.237 Mpa respectively. Stress value was relatively high at the central part of interbody fusion. And all the highest values were localized at the first thread below the central part. Result of comparison between three conditions: torque load was the highest, followed by vertical load and lateral bending. CONCLUSION: Percutaneous axial lumbosacral screw can meet the normal loading conditions. Further clinical applications are recommended.


Assuntos
Parafusos Ósseos , Análise de Elementos Finitos , Modelos Biológicos , Fusão Vertebral/métodos , Fenômenos Biomecânicos , Computadores Analógicos , Humanos , Fixadores Internos , Vértebras Lombares/cirurgia
13.
Orthop Surg ; 2(3): 207-10, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22009950

RESUMO

OBJECTIVE: To establish a three-dimensional finite element model of the L(5)/S(1) motion segment with percutaneous axial lumbosacral screw and analyze the biomechanical stress on the screw. METHODS: With the help of related software and the Mechanical Virtual Human of China, a three-dimensional finite element model was established. Three different loading conditions on the screw were analyzed with this model. RESULTS: Peak stresses on the screw under three loading conditions were 175.334 MPa, 183.765 MPa and 146.237 MPa, respectively. Generally, stress values were relatively low. The stress values were relatively high at the point of interbody fusion and middle part of the screw, all the highest values being localized to the upper and lower threads closest to the middle part. Comparison among the three conditions showed that torque load was the greatest, followed by vertical load, with lateral bending being the least. CONCLUSION: Percutaneous axial lumbosacral screw easily meets normal loading conditions and may be an effective method for lumbosacral fusion.


Assuntos
Parafusos Ósseos , Análise de Elementos Finitos , Vértebras Lombares/cirurgia , Sacro/cirurgia , Fusão Vertebral/instrumentação , Fenômenos Biomecânicos , Humanos , Região Lombossacral , Fusão Vertebral/métodos , Estresse Mecânico , Suporte de Carga
14.
Zhonghua Yi Xue Za Zhi ; 88(37): 2609-13, 2008 Oct 14.
Artigo em Chinês | MEDLINE | ID: mdl-19080707

RESUMO

OBJECTIVE: To establish an in vitro model of natural degeneration of lumbar endplate chondrocytes and explore the role and the expression change of Sox9 gene, an important gene in the differentiation and maturation of chondrocyte, in the process of natural degeneration of endplate chondrocytes. METHODS: The lumbar vertebrae of 35 SD rats were taken out to obtain the endplates. Endplate chondrocytes were isolated by enzyme digestion and cultured so as to establish an in vitro natural degeneration model of chondrocytes. The morphological appearances and biological characteristics of the chondrocytes of different generations were observed by HE staining, immunocytochemical staining and toluidine blue et cetera; RT-PCR was used to detect the mRNA expression of Sox9 gene and type II collagen in differential generations. RESULTS: The lumbar cartilaginous endplate chondrocytes of rat expressed collagen II, and it's phenotype and biological characteristics were similar to those of articular cartilage cells. When the cells were passaged to the forth or fifth generations they were fusiform and their proliferative speed decreased. Compared with the primary generation chondrocytes, the expression of Sox9 mRNA in the forth and fifth generation chondrocytes was markedly decreased (P < 0.05). And the mRNA expression level of type II collagen, regulated by Sox9 gene, decreased too (P < 0.05). The mRNA expression of Sox9 was positively correlated with the mRNA expression of type II collagen (r = 0.912, P < 0.05). CONCLUSION: A model of natural degeneration of lumbar endplate chondrocytes has been established successfully, thus providing a good cytological basis for the study of degeneration of lumbar endplate. Sox9 gene may play a role in the process of natural degeneration of endplate chondrocytes.


Assuntos
Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Deslocamento do Disco Intervertebral/metabolismo , Fatores de Transcrição SOX9/genética , Animais , Colágeno Tipo II , Modelos Animais de Doenças , Expressão Gênica , Vértebras Lombares , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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