Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 41
Filter
1.
Chinese Medical Sciences Journal ; (4): 17-26, 2021.
Article in English | WPRIM | ID: wpr-879305

ABSTRACT

Objective This study aimed to determine the association of hyperlipidemia with clinical endpoints among hospitalized patients with COVID-19, especially those with pre-existing cardiovascular diseases (CVDs) and diabetes. Methods This multicenter retrospective cohort study included all patients who were hospitalized due to COVID-19 from 21 hospitals in Hubei province, China between December 31, 2019 and April 21, 2020. Patients who were aged < 18 or ≥ 85 years old, in pregnancy, with acute lethal organ injury (e.g., acute myocardial infarction, severe acute pancreatitis, acute stroke), hypothyroidism, malignant diseases, severe malnutrition, and those with normal lipid profile under lipid-lowering medicines (e.g., statin, niacin, fenofibrate, gemfibrozil, and ezetimibe) were excluded. Propensity score matching (PSM) analysis at 1:1 ratio was performed to minimize baseline differences between patient groups of hyperlipidemia and non-hyperlipidemia. PSM analyses with the same strategies were further conducted for the parameters of hyperlipidemia in patients with increased triglyceride (TG), increased low-density lipoprotein cholesterol (LDL-C), and decreased high-density lipoprotein cholesterol (HDL-C). Mixed-effect Cox model analysis was performed to investigate the associations of the 28-days all-cause deaths of COVID-19 patients with hyperlipidemia and the abnormalities of lipid parameters. The results were verified in male, female patients, and in patients with pre-existing CVDs and type 2 diabetes. Results Of 10 945 inpatients confirmed as COVID-19, there were 9822 inpatients included in the study, comprising 3513 (35.8%) cases without hyperlipidemia and 6309 (64.2%) cases with hyperlipidemia. Based on a mixed-effect Cox model after PSM at 1:1 ratio, hyperlipidemia was not associated with increased or decreased 28-day all-cause death [adjusted hazard ratio (


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , COVID-19/therapy , Cardiovascular Diseases/complications , Case-Control Studies , Cause of Death , China/epidemiology , Diabetes Mellitus, Type 2/complications , Hospitalization , Hyperlipidemias/complications , Propensity Score , Proportional Hazards Models , Retrospective Studies , Risk Factors
2.
Chinese Medical Journal ; (24): 2588-2593, 2019.
Article in English | WPRIM | ID: wpr-774882

ABSTRACT

BACKGROUND@#Refractory femoral neck fractures cannot be anatomically reduced by closed traction reduction which may affect fracture healing. We evaluated the biomechanical effects of positive, negative, and anatomic reduction of various degrees of displacement in Pauwels I femoral neck fractures by a finite element analysis.@*METHODS@#Five reduction models of Pauwels type I femoral neck fracture were established using the Mimics 17.0 (Materialize, Leuven, Belgia) and Hypermesh 12.0 (Altair Engineering, Troy, MI, USA). According to the degree of fracture displacement, there were three models of positive support, an anatomic reduction model, and a negative 2 mm reduction model. Finite element analysis was conducted using the ABAQUS 6.9 software (Simulia, Suresnes, France). The von Mises stress distribution and the stress peak of internal fixation in different models, the displacement between fracture blocks, and the principal strain of the femoral neck cancellous bone model were recorded under the axial stress of 2100 N.@*RESULTS@#The peak von Mises stress on screw of each model was located at the thread of the screw tip. The peak von Mises stress was the lowest at the tip of the anatomic reduction model screw (261.2 MPa). In the positive 4 mm model, the von Mises stress peak was the highest (916.1 MPa). The anatomic reduction model showed the minimum displacement (0.388 mm) between fracture blocks. The maximum displacement was noted in the positive 4 mm model (0.838 mm). The displacement in the positive 3 mm model (0.721 mm) was smaller than that in the negative 2 mm model (0.786 mm). Among the five models, the strain area of the femoral neck cancellous bone was mainly concentrated around the screw hole, and the area around the screw hole could be easily cut.@*CONCLUSIONS@#Compared with negative buttress for femoral neck fracture, positive buttress can provide better biomechanical stability. In Pauwel type I fracture of femoral neck, the range of positive buttress should be controlled below 3 mm as far as possible.

3.
Chinese Medical Journal ; (24): 2588-2593, 2019.
Article in English | WPRIM | ID: wpr-803152

ABSTRACT

Background@#Refractory femoral neck fractures cannot be anatomically reduced by closed traction reduction which may affect fracture healing. We evaluated the biomechanical effects of positive, negative, and anatomic reduction of various degrees of displacement in Pauwels I femoral neck fractures by a finite element analysis.@*Methods@#Five reduction models of Pauwels type I femoral neck fracture were established using the Mimics 17.0 (Materialize, Leuven, Belgia) and Hypermesh 12.0 (Altair Engineering, Troy, MI, USA). According to the degree of fracture displacement, there were three models of positive support, an anatomic reduction model, and a negative 2 mm reduction model. Finite element analysis was conducted using the ABAQUS 6.9 software (Simulia, Suresnes, France). The von Mises stress distribution and the stress peak of internal fixation in different models, the displacement between fracture blocks, and the principal strain of the femoral neck cancellous bone model were recorded under the axial stress of 2100 N.@*Results@#The peak von Mises stress on screw of each model was located at the thread of the screw tip. The peak von Mises stress was the lowest at the tip of the anatomic reduction model screw (261.2 MPa). In the positive 4 mm model, the von Mises stress peak was the highest (916.1 MPa). The anatomic reduction model showed the minimum displacement (0.388 mm) between fracture blocks. The maximum displacement was noted in the positive 4 mm model (0.838 mm). The displacement in the positive 3 mm model (0.721 mm) was smaller than that in the negative 2 mm model (0.786 mm). Among the five models, the strain area of the femoral neck cancellous bone was mainly concentrated around the screw hole, and the area around the screw hole could be easily cut.@*Conclusions@#Compared with negative buttress for femoral neck fracture, positive buttress can provide better biomechanical stability. In Pauwel type I fracture of femoral neck, the range of positive buttress should be controlled below 3 mm as far as possible.

4.
Chinese Journal of Rehabilitation Theory and Practice ; (12): 437-441, 2018.
Article in Chinese | WPRIM | ID: wpr-702512

ABSTRACT

Objective To observe the effect of isokinetic training of knee flexors and extensors on walking ability in patients with knee osteoarthritis(KOA). Methods From December,2016 to June,2017,120 patients with KOA in our hospital were randomly divided into blank group(n=40),control group(n=40)and observation group(n=40).All the groups were injected with sodium hyal-uronate intraluminally,and received joint mobilization.The control group added conventional strength training, including isotonic and isometric static squat exercise of muscles around the knee. The observation group re-ceived knee isokinetic training additionally,the training mode was ordinary isokinetic/centripetal mode.Before and four weeks after treatment, the peak torque (PT), the Lysholm score and Visual Analogue Scale (VAS) for pain,ten-meter walking time and six-minute walking distance were tested. Results After treatment,the PT value of knee flexors and extensors,the scores of VAS and Lysholm,ten-meter walking time and six-minute walking distance significantly improved in all groups(P<0.05),among which the observa-tion group was the best(P<0.05). Conclusion Isokinetic muscle strength training of knee flexors and extensors can improve the walking ability of patients with KOA.

5.
Chinese Journal of Tissue Engineering Research ; (53): 1743-1748, 2018.
Article in Chinese | WPRIM | ID: wpr-698607

ABSTRACT

BACKGROUND: Although more and more accurate and personalized detection and assistive tools are used in the field of orthopedics with the development of technology, the preoperative CT is still the first-line examination choice of many orthopedic surgeons. Therefore, to master the lumbar spine CT imaging performance is not only the basis of spine surgeons, but also the cornerstone of spinal nail surgery. OBJECTIVE: Through CT imaging technique, we measured the parameters of lumbar pedicle imaging, and understood its internal structure as the basis for the choice of screws, in order to improve the safety and accuracy of nail surgery. METHODS: Totally 36 cases without lumbar vertebrae-related disease undergoing lumbar vertebra and abdominal cavity CT scan were randomly selected, including 20 males and 16 females at the age of (43.3±12.3) years. PACS was used to reconstruct lumbar vertebrae, and the related imaging parameters were measured. RESULTS AND CONCLUSION: (1) There was no significant difference between the left and right sides of the pedicle for paired t-test (P >0.05). (2) Pedicle sagittal angle had downward trend, the level of change was small; L4increased relative to L3; L5level was minimum at the average of -1.3°. Pedicle transverse angle had gradually increased trend, and maximum at L5; the average was 25.4°. (3) The length of the pedicle channel increased first and then decreased in the lumbar segment; the longest average was 52.2 mm in the L2segment, the shortest at L5, with an average of 47.4 mm. (4) The pedicle height was slightly narrowed at L1-L3levels; the smallest was 15.4 mm (L3mean), and reached the maximum in the L5at 22.7 mm (L5mean). Cancellous bone height also showed the same trend, the minimum in the L3at 10.2 mm, the maximum in the L5at 17.9 mm. (5) Lumbar pedicle width showed an upward trend, L1minimum of 7.7 mm, L5maximum of 12.5 mm. Cancellous bone width also became a similar upward trend; the narrowest L1, averagely 4.9 mm; the maximum L5, averagely 8.5 mm. (6) Overall, the upper lumbar pedicle channel was slender, while the lower lumbar spine was slightly short. (7) The parameters of the pedicle can be used as the basis for selecting the appropriate screw. At the same time, lumbar pedicle morphology has a certain difference, and there is a certain law. Accurately grasping its structure and image characteristics of pedicle screw fixation is the basis of surgery. The preoperative imaging data collection and assessment, combined with the general situation of patients, and the development of personalized programming, will help in improving the safety and accuracy of screw placement.

6.
Chinese Journal of Tissue Engineering Research ; (53): 1026-1031, 2018.
Article in Chinese | WPRIM | ID: wpr-698493

ABSTRACT

BACKGROUND: Patients with anterior cervical discectomy and fusion have a high incidence of dysphagia, which may be associated with a variety of factors. The specific mechanism remains unclear. OBJECTIVE: To explore the related factors of dysphagia after single-level anterior cervical discectomy and fusion. METHODS: We retrospectively analyzed patients with cervical degenerative disc disease receiving single-level anterior cervical discectomy and fusion in First Affiliated Hospital of Soochow University from January 2011 to January 2015. During hospitalization, basic patient data and surgery-related data were recorded, including operation time, intraoperative blood loss, surgical segment, internal fixation device and the use of recombinant human bone morphogenetic protein-2. The cervical alignment and prevertebral soft tissue swelling were measured preoperatively and 3 days postoperatively. At 1, 3, 6, 12, and 24 months postoperatively, the Bazaz swallowing function scoring system was used to assess the swallowing of the patients. RESULTS AND CONCLUSION: A total of 262 patients undergoing single-level anterior cervical discectomy and fusion were involved. The incidence of dysphagia at 1, 3, 6, 12, and 24 months postoperatively was 35.9%, 22.9%, 15.6%, 11.5% and 9.2% respectively. Univariate analysis showed that gender, operation time and course length were associated with postoperative dysphagia. Logistic multivariate regression analysis showed that the duration of operation (≥ 3 hours), female and course length (≥ 8 months) were risk factors for dysphagia after anterior cervical descectomy and fusion. Operation time and female may be associated with early and middle dysphagia postoperatively, and the course length may be associated with chronic dysphagia. Prevertebral soft tissue swelling and other factors are not related to dysphagia after single-level anterior cervical discectomy and fusion. Risk factors for dysphagia after multi-level fusion should be further studied.

7.
Chinese Journal of Tissue Engineering Research ; (53): 1020-1025, 2018.
Article in Chinese | WPRIM | ID: wpr-698492

ABSTRACT

BACKGROUND: The short-term effects of dynamic internal fixation and whether dynamic internal fixation system can prevent or delay the process of adjacent level degeneration after lumbar surgery remain in controversy.OBJECTIVE: To investigate the short-term clinical effectiveness of single-level Isobar TTL dynamic internal fixation in the treatment of degenerative lumbar diseases. METHODS: Data of 20 patients who suffered from lumbar degenerative diseases and underwent posterior decompression combined with single-level Isobar TTL dynamic internal fixation, including 11 male patients and 9 female patients, were retrospectively analyzed; the average age of these patients was 47.4 (35-62) years old. Visual analog scale, Japanese Orthopaedic Association scores and Oswestry disability index were used to assess clinical outcomes. Disc height, range of motion, and University of California at Los Angeles Grading Scale were measured on X-ray films to evaluate the status of disc degeneration on both dynamic fixed segment (index segment) and superior adjacent segment. RESULTS AND CONCLUSION: All follow-up patients successfully completed the operation. The average follow-up time was 14.4 (12-27) months. No blood vessels, nerve injury, loose internal fixation or rupture occurred. At the last follow-up, Visual Analog Scale, Japanese Orthopaedic Association scores and Oswestry Disability Index were significantly improved (P < 0.05); range of motion of dynamic fixation segment reduced (P < 0.05) as compared with that before surgery. Intervertebral height of dynamic fixation segments and University of California at Los Angeles Grading Scale classification were not significantly different between follow-up and before surgery (P > 0.05). Intervertebral height of superior adjacent segment, intervertebral range of motion and University of California at Los Angeles Grading Scale classification were not significantly different (P > 0.05). These results indicate that single-level Isobar TTL dynamic internal fixation proved to have satisfactory clinical outcomes in the treatment of lumbar degenerative diseases. During follow-up, disc degeneration on either index segment or superior adjacent segment is not accelerated.

8.
Journal of Medical Biomechanics ; (6): 422-426, 2017.
Article in Chinese | WPRIM | ID: wpr-669095

ABSTRACT

Objective To investigate the effect of cervical spinous process fracture with posterior ligamentous complex (PLC) injury on biomechanical stability of the goat cervical spine specimen in vitro,and evaluate the role of posterior structure in maintaining the stability of cervical spine.Methods Twenty-four fresh goat cervical spine C3-6 specimens were randomly and evenly divided into 3 groups:control group (group A),simple cervical spinous process fracture group (group B) and cervical spinous process fracture with PLC injury group (group C).Under loading of 1.5 N · m torque,the range of motion (ROM) in each group was respectively measured under 6 working conditions:flexion,extension,lateral bending and axial rotation,and the ROM differences among 3 groups were compared by using one-way ANOVA analysis.Results Simple cervical spinous process fracture had little effect on the stability of cervical spine and there was no significant difference in ROM between group B and control group (P > 0.05) under all working conditions.Compared with control group,the ROM in flexion,extension and axial rotation significantly increased in group C (P < 0.05),and no significant ROM difference was found in lateral bending between control group and group C (P > 0.05).Conclusions Simple cervical spinous process fracture does not affect the overall stability of cervical spine.Cervical spinous process fracture with PLC injury is more likely to cause cervical instability than simple cervical spinous process fracture,and surgical intervention is required in cervical spinous process fracture with PLC injury.

9.
Journal of Medical Biomechanics ; (6): E422-E426, 2017.
Article in Chinese | WPRIM | ID: wpr-803868

ABSTRACT

Objective To investigate the effect of cervical spinous process fracture with posterior ligamentous complex (PLC) injury on biomechanical stability of the goat cervical spine specimen in vitro, and evaluate the role of posterior structure in maintaining the stability of cervical spine. Methods Twenty-four fresh goat cervical spine C3-6 specimens were randomly and evenly divided into 3 groups: control group (group A), simple cervical spinous process fracture group (group B) and cervical spinous process fracture with PLC injury group (group C). Under loading of 1.5 N·m torque, the range of motion (ROM) in each group was respectively measured under 6 working conditions: flexion, extension, lateral bending and axial rotation, and the ROM differences among 3 groups were compared by using one-way ANOVA analysis. Results Simple cervical spinous process fracture had little effect on the stability of cervical spine and there was no significant difference in ROM between group B and control group (P>0.05) under all working conditions. Compared with control group, the ROM in flexion, extension and axial rotation significantly increased in group C (P0.05). Conclusions Simple cervical spinous process fracture does not affect the overall stability of cervical spine. Cervical spinous process fracture with PLC injury is more likely to cause cervical instability than simple cervical spinous process fracture, and surgical intervention is required in cervical spinous process fracture with PLC injury.

10.
Asian Pacific Journal of Tropical Medicine ; (12): 714-717, 2017.
Article in English | WPRIM | ID: wpr-819469

ABSTRACT

OBJECTIVE@#To assess the effects of axial vibrations on gene expression and lumbar intervertebral disc degeneration in vivo.@*METHODS@#A modified bipedal rat model was established using a brachial plexus rhizotomy approach to imitate human upright posture. The experimental animals were randomly divided into three groups: control, vertical vibration, and whole-body vibration. Gene expression in degeneration of the intervertebral discs was assessed by reverse transcription-quantitative polymerase chain reaction.@*RESULTS@#The expression of aggrecan, Col1α1, Col2α1, and decorin were shown to be up-regulated in 14-week-old rats in the vertical vibration and whole-body vibration groups, whereas biglycan and versican expression was down-regulated in 14-week-old rats of the two experimental groups. Furthermore, biglycan and versican expression levels were shown to be lower in the whole-body vibration group than in the vertical vibration group (P < 0.05).@*CONCLUSIONS@#This in-vivo study demonstrated that vibrations can influence the expression of anabolic genes. Furthermore, whole-body vibrations seem to have a greater effect in this regard than vertical vibrations. A new method is expected to relieve the low back pain of the patients through our research.

11.
Asian Pacific Journal of Tropical Medicine ; (12): 714-717, 2017.
Article in Chinese | WPRIM | ID: wpr-972600

ABSTRACT

Objective To assess the effects of axial vibrations on gene expression and lumbar intervertebral disc degeneration in vivo. Methods A modified bipedal rat model was established using a brachial plexus rhizotomy approach to imitate human upright posture. The experimental animals were randomly divided into three groups: control, vertical vibration, and whole-body vibration. Gene expression in degeneration of the intervertebral discs was assessed by reverse transcription-quantitative polymerase chain reaction. Results The expression of aggrecan, Col1α1, Col2α1, and decorin were shown to be up-regulated in 14-week-old rats in the vertical vibration and whole-body vibration groups, whereas biglycan and versican expression was down-regulated in 14-week-old rats of the two experimental groups. Furthermore, biglycan and versican expression levels were shown to be lower in the whole-body vibration group than in the vertical vibration group (P < 0.05). Conclusions This in-vivo study demonstrated that vibrations can influence the expression of anabolic genes. Furthermore, whole-body vibrations seem to have a greater effect in this regard than vertical vibrations. A new method is expected to relieve the low back pain of the patients through our research.

12.
Experimental & Molecular Medicine ; : e329-2017.
Article in English | WPRIM | ID: wpr-17709

ABSTRACT

Osteosarcoma is suggested to be caused by genetic and molecular alterations that disrupt osteoblast differentiation. Recent studies have reported that transmembrane protein 119 (TMEM119) contributes to osteoblast differentiation and bone development. However, the level of TMEM119 expression and its roles in osteosarcoma have not yet been elucidated. In the present study, TMEM119 mRNA and protein expression was found to be up-regulated in osteosarcoma compared with normal bone cyst tissues. The level of TMEM119 protein expression was strongly associated with tumor size, clinical stage, distant metastasis and overall survival time. Moreover, gene set enrichment analysis (GSEA) of the Gene Expression Omnibus (GEO) GSE42352 dataset revealed TMEM119 expression in osteosarcoma tissues to be positively correlated with cell cycle, apoptosis, metastasis and TGF-β signaling. We then knocked down TMEM119 expression in U2OS and MG63 cells using small interfering RNA, which revealed that downregulation of TMEM119 could inhibit the proliferation of osteosarcoma cells by inducing cell cycle arrest in G0/G1 phase and apoptosis. We also found that TMEM119 knockdown significantly inhibited cell migration and invasion, and decreased the expression of TGF-β pathway-related factors (BMP2, BMP7 and TGF-β). TGF-β application rescued the inhibitory effects of TMEM119 knockdown on osteosarcoma cell migration and invasion. Further in vitro experiments with a TGF-β inhibitor (SB431542) or BMP inhibitor (dorsomorphin) suggested that TMEM119 significantly promotes cell migration and invasion, partly through TGF-β/BMP signaling. In conclusion, our data support the notion that TMEM119 contributes to the proliferation, migration and invasion of osteosarcoma cells, and functions as an oncogene in osteosarcoma.


Subject(s)
Apoptosis , Bone Cysts , Bone Development , Cell Cycle , Cell Cycle Checkpoints , Cell Movement , Dataset , Down-Regulation , Gene Expression , In Vitro Techniques , Neoplasm Metastasis , Oncogenes , Osteoblasts , Osteosarcoma , RNA, Messenger , RNA, Small Interfering , Up-Regulation
13.
Journal of Medical Biomechanics ; (6): E061-E066, 2016.
Article in Chinese | WPRIM | ID: wpr-804069

ABSTRACT

Objective To study the effects on compressive strength and rigidity of tibia cortical bone from deep-freezing, freeze-drying or radiation treatments, and to discuss the appropriate method for tibia cortical bone treatment. Methods The cortical bone were collected from the middle part in tibial diaphysis from amputated limbs of trauma patients and made into bone plates with the size of 10 mm×10 mm×5 mm each. The bone plates were then divided into seven groups evenly and randomly: control group (Group A), deep-freezing group (Group B), freeze-drying group(Group C), deep-freezing plus 60Co (25 J/g) radiation group(Group D), deep-freezing plus 60Co (50 J/g) radiation group(Group E), freeze-drying plus 60Co (25 J/g) radiation group(Group F), freeze-drying plus 60Co (50 J/g) radiation group(Group G). The compressive strength and rigidity of allograft cortical bone were tested by mechanical testing machine. Results The largest compressive strength of the tibia cortical bone was in the range of 6.089-9.089 kN. Compared with Group A, the strength in Group B, C, D and F showed no significant difference, and the rigidity in Group B and C showed no significant difference, while the rigidity in Group D and F was decreased by 9.6% (P<0.05) and 8.7% (P<0.05), respectively. Compared with Group A, the strength in Group E and G was reduced by 29.6% (P<0.05) and 33.1% (P<0.05), respectively, and the rigidity was reduced by 16.7% (P<0.05) and 14.8% (P<0.05), respectively. Conclusions The strength and rigidity of tibia cortical bone are not changed significantly after deep-freezing or freeze-drying treatment. Compared with the untreated group, the strength of tibial cortical bone with the small dosage of 60Co treatment is not significantly changed after deep-freezing or freeze-drying, but the rigidity is decreased; the strength and rigidity with the large dosage of 60Co treatment are decreased obviously. For application of cortical bone used in spinal fusion, radiation sterilization dosage should be controlled in the range of 15-25 J/g.

14.
Chinese Medical Journal ; (24): 1121-1127, 2015.
Article in English | WPRIM | ID: wpr-350341

ABSTRACT

<p><b>OBJECTIVE</b>The purpose of this study was to review the current status of calcium phosphate (CaP) scaffolds combined with bone morphogenetic proteins (BMPs) or mesenchymal stem cells (MSCs) in the field of bone tissue engineering (BTE).</p><p><b>DATE SOURCES</b>Data cited in this review were obtained primarily from PubMed and Medline in publications from 1979 to 2014, with highly regarded older publications also included. The terms BTE, CaP, BMPs, and MSC were used for the literature search.</p><p><b>STUDY SELECTION</b>Reviews focused on relevant aspects and original articles reporting in vitro and/or in vivo results concerning the efficiency of CaP/BMPs or CaP/MSCs composites were retrieved, reviewed, analyzed, and summarized.</p><p><b>RESULTS</b>An ideal BTE product contains three elements: Scaffold, growth factors, and stem cells. CaP-based scaffolds are popular because of their outstanding biocompatibility, bioactivity, and osteoconductivity. However, they lack stiffness and osteoinductivity. To solve this problem, composite scaffolds of CaP with BMPs have been developed. New bone formation by CaP/BMP composites can reach levels similar to those of autografts. CaP scaffolds are compatible with MSCs and CaP/MSC composites exhibit excellent osteogenesis and stiffness. In addition, a CaP/MSC/BMP scaffold can repair bone defects more effectively than an autograft.</p><p><b>CONCLUSIONS</b>Novel BTE products possess remarkable osteoconduction and osteoinduction capacities, and exhibit balanced degradation with osteogenesis. Further work should yield safe, viable, and efficient materials for the repair of bone lesions.</p>


Subject(s)
Animals , Humans , Bone Morphogenetic Proteins , Chemistry , Bone and Bones , Cell Biology , Calcium Phosphates , Chemistry , Mesenchymal Stem Cells , Cell Biology , Tissue Engineering , Methods , Tissue Scaffolds , Chemistry
15.
Journal of Medical Biomechanics ; (6): E197-E202, 2015.
Article in Chinese | WPRIM | ID: wpr-804466

ABSTRACT

Objective To explore the effects of dynamic axial compressive strain on the mRNA expression of bone formation related-genes in osteoblasts seeded in 3D silk fibroin scaffolds. Methods In the experimental group, MC3T3-E1 cells were seeded in 3D scaffolds and then subjected to dynamic axial compressive strain (at amplitude of 5% and frequency of 1 Hz, 30 min/day for 20 days), while in the control group, MC3T3-E1 cells were cultured statically without any mechanical stimulation. The gene expression of alkaline phosphatase (ALP), collagenⅠ(COL-Ⅰ), runt-related transcription factor 2 (Runx2), osterix (Osx), osteocalcin (OCN) was detected by real-time PCR. Results Under cyclic axial compressive strain, the Runx2, Osx and COLⅠmRNA levels increased by 280%, 68.9% and 79.6%, respectively, while the ALP and OC mRNA levels also up-regulated by 10.7% and 26.9%, respectively. There were significant differences in mRNA expression of osteogenesis-related genes between the experimental group and control group (P<0.05). Conclusions Under the stimulation of cyclic axial compressive strain, the osteogenic differentiation of osteoblasts seeded in the silk fibroin scaffolds is promoted, with a significant up-regulation in the mRNA expression of COLⅠ, Runx2, Osx and OCN, which suggests that the stimulation of compressive stress at physiologic magnitude could be one of important mechanisms in promoting fracture healing. This research finding will be important for the clinic application of mechanical stimuli-mediated cell therapy for bone defection.

16.
Journal of Korean Neurosurgical Society ; : 36-41, 2015.
Article in English | WPRIM | ID: wpr-166147

ABSTRACT

OBJECTIVE: To investigate the causes for failed anterior cervical surgery and the outcomes of secondary laminoplasty. METHODS: Seventeen patients failed anterior multilevel cervical surgery and the following conservative treatments between Feb 2003 and May 2011 underwent secondary laminoplasty. Outcomes were evaluated by the Japanese Orthopaedic Association (JOA) Scale and visual analogue scale (VAS) before the secondary surgery, at 1 week, 2 months, 6 months, and the final visit. Cervical alignment, causes for revision and complications were also assessed. RESULTS: With a mean follow-up of 29.7+/-12.1 months, JOA score, recovery rate and excellent to good rate improved significantly at 2 months (p0.05). Mean VAS score decreased postoperatively (p0.05). The causes for secondary surgery were inappropriate approach in 3 patients, insufficient decompression in 4 patients, adjacent degeneration in 2 patients, and disease progression in 8 patients. Complications included one case of C5 palsy, axial pain and cerebrospinal fluid leakage, respectively. CONCLUSION: Laminoplasty has satisfactory results in failed multilevel anterior surgery, with a low incidence of complications.


Subject(s)
Humans , Asian People , Cerebrospinal Fluid , Decompression , Disease Progression , Follow-Up Studies , Incidence , Paralysis , Spondylosis
17.
Chinese Journal of Traumatology ; (6): 193-197, 2014.
Article in English | WPRIM | ID: wpr-358865

ABSTRACT

<p><b>OBJECTIVE</b>Autophagy is involved in several neurodegenerative diseases and recently its role in acute brain injury has won increasing interest. Spinal cord injuries (SCIs) often lead to permanent neurological deficit. Therefore, in this study, we examined the pro?les of autophagy-linked proteins (MAP-LC3) after SCI to investigate whether the expression of autophagy contributes to neurological deficit after SCI.</p><p><b>METHODS</b>Adult female Sprague-Dawley rats were used and randomly divided into control and SCI groups. All the rates received laminectomy at T8-T10 level. Those in the SCI group received additional exposure of the dorsal surface of the spinal cord, followed by a weight- drop injury. Thereafter we investigated the expression levels of MAP-LC3, beclin-1, Cathepsin D and the beclin-1-binding protein bcl-2 by western blot analysis at 12 h, 24 h, 3 d, 7 d, 21 d and 28 d. One-way ANOVA with Tukey post hoc test was used to compare data between groups.</p><p><b>RESULTS</b>We observed significant increase in the level of LC3 (LC3-II/LC3-I) at 3 d and 7 d after SCI when compared with the sham group. While the level of beclin-1 and ratio of beclin-1/bcl-2 was found to have increased from 12 h to 24 h after injury. Cathepsin D expression was also elevated at 7 d (P<0.01).</p><p><b>CONCLUSION</b>Based on the above mentioned data, we proposed that autophagy plays a role in the manifestation of cell injury following SCI.</p>


Subject(s)
Animals , Female , Rats , Adaptor Proteins, Signal Transducing , Metabolism , Apoptosis Regulatory Proteins , Metabolism , Autophagy , Physiology , Beclin-1 , Blotting, Western , Cathepsin D , Metabolism , Disease Models, Animal , Laminectomy , Microtubule-Associated Proteins , Metabolism , Rats, Sprague-Dawley , Spinal Cord Injuries , Metabolism
18.
Journal of Medical Biomechanics ; (6): E405-E410, 2014.
Article in Chinese | WPRIM | ID: wpr-804343

ABSTRACT

Objective To analyze the clinical feasibility of unilateral transforaminal lumbar interbody fusion (TLIF) for treating lumbar degenerative diseases by finite element method. Methods Based on CT scan data, three-dimensional (3D) finite element models of the normal L3-5 segments under physiological status (intact lumbar model), L4/5 with unilateral pedicle screw fixation plus interbody fusion (unilateral TLIF model) and L4/5 with bilateral pedicle screw fixation plus interbody fusion (bilateral TLIF model) were established by using Mimics, Pro/E, ANSYS software, respectively. Preload of 500 N and load of 10 N•m torque were applied on the superior surface of the L3 segment to simulate 5 physiological activities: body upright, flexion, extension, left lateral bending and right axial rotation. The deformation and stress distributions in vertebral body, vertebral discs, pedicle screw and cage under different loads were then recorded and analyzed to compare mechanical properties of the two fixation methods. Results The deformation of L3-5 segments fixed with unilateral TLIF or bilateral TLIF decreased as compared to the intact lumbar model; the stresses in cage reached the maximum in both unilateral TLIF model and bilateral TLIF model during back extension, meanwhile peak stresses on pedicle screws in unilateral TLIF were significantly higher than those on bilateral TILF model, with the peak stress of 463.39 MPa during back extension. ConclusionsUnilateral TLIF can be selected as a method for treating lumbar degenerative diseases; however, its stability was inferior to bilateral TLIF due to the higher peak stress. Therefore, less stretch exercises may be safe for patients during rehabilitation to avoid surgery failure or pedicle screw fracture.

19.
Chinese Medical Journal ; (24): 729-733, 2013.
Article in English | WPRIM | ID: wpr-342509

ABSTRACT

<p><b>BACKGROUND</b>Tendon adhesion is one of the most common causes of disability following tendon surgery. Therefore, prevention of peritendinous adhesion after surgical repair of tendon is a major challenge. The aim of this study was to explore the possible application of a collagen membrane for the prevention or attenuation of peritendinous adhesions.</p><p><b>METHODS</b>Sprague-Dawley (SD) rat Achilles tendon was cut and sutured by a modified Kessler's technique with or without the collagen membrane wrapped. Macroscopic, morphological and biomechanical evaluations were applied to examine the recovery of the injured tendon at 4 and 8 weeks after surgery.</p><p><b>RESULTS</b>The surgery group wrapped by collagen membranes had a better outcome than the group with surgery repair only. In the collagen membrane-treated group, less adhesion appeared, stronger tensile strength was detected, and more tendon fibers and collagen I expression were observed morphologically.</p><p><b>CONCLUSION</b>Wrapping the tendon with a collagen membrane may be an efficient approach for tendon repair and preventing tendon adhesion after its ruptures.</p>


Subject(s)
Animals , Male , Rats , Achilles Tendon , Wounds and Injuries , Collagen , Rats, Sprague-Dawley , Tendon Injuries , General Surgery , Tissue Adhesions , Wound Healing
SELECTION OF CITATIONS
SEARCH DETAIL