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Minimally invasive surgery has become a trend in modern orthopedic surgery,and the demand for intraoperative imaging has gradually increased.Good intraoperative imaging can assist the orthopaedic surgeon in accurately positioning the anatomy and placing the internal fixation.However,intraoperative imaging inevitably exposes the orthopaedic surgeon and patient to ionizing radiation,and radiation exposure can induce DNA damage and reactive oxygen species.Production results in cell damage that often leads to cell death or genomic instability leading to increased risk of various radiation-related conditions,including malignancy.Although the traditional intraoperative fluoroscopy operating room will be equipped with lead clothing and lead collar to reduce radiation exposure,it is not known whether the lead clothing and lead-covered parts are safe.Therefore,radiation safety has become an inevitable problem for orthopedic surgeons in intraoperative imaging,and how to effectively reduce and avoid unnecessary exposure to ionizing radiation is particularly important for bone surgeons and patients.This article aims to review the occupational exposure and radiation safety of intraoperative imaging in orthopaedic surgery.
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BACKGROUND:Fractures can induce bone cel hypoxia, and remarkably reduce the oxygen tension in cels. Hypoxia-inducible factor-2α is a key oxygen-dependent transcriptional activator to regulate the body function under hypoxia and mediate the release of various inflammatory factors after fractures. OBJECTIVE:To explore the role of Laquinimod in expression and function of hypoxia-inducible factor-2αin osteoblasts. METHODS: Mouse osteoblasts MC3T3-E1 (clone 14) were pretreated with Laquinimod at various concentrations(10-100μmol/L) before hypoxia in the presence or absence of specific proteasome inhibitors MG132 or N-acetyl-leucyl-leucyl-norleucine. Then, the media were pre-conditioned in 1% or 21% oxygen tension for 1 to 24 hours. RESULTS AND CONCLUSION: Under hypoxia, the expression of hypoxia-inducible factor-2α in osteoblasts was increased remarkably, and Laquinimod could inhibit the expression of hypoxia-inducible factor-2α and its target genes in mouse MC3T3-E1 cels. Mechanisticaly, Laquinimod promoted hypoxia-inducible factor-2α degradation in a proteasome-dependent but von Hippel-Lindau protein-independent manner. Importantly, we found that Laquinimod disrupted the interaction between hypoxia-inducible factor-2α and its chaperone heat shock protein 90, but promoted the interaction between hypoxia-inducible factor-2α and the receptor of activated protein kinase C. These findings suggest that Laquinimod may promote the degradation of hypoxia-inducible factor-2α by affecting its folding and maturation. Laquinimod is a novel inhibitor of hypoxia-inducible factor-2α by changing its functional interaction with chaperone proteins heat shock protein 90 and receptor of activated protein kinase C.
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Objective To investigate the immunologic properties of osteogenic differentiated bone mesenchymal stem cells (BMSCs). Methods BMSCs were isolated from normal volunteers and induced in osteogenic medium for two weeks. Then,non-differentiated/osteogenic differentiated BMSCs were co-cultured with allogenic T cells and phytohemagglutinin (PHA).The proliferation of T cells was examined by MTT method.The concentrations of TGF-β1 in osteogenic differentiated BMSCs supernatants at week 2 and mixed lymphocytes reaction (MLR) supernatants at day 5 were determined by ELISA.Also,anti-TGF-β antibody was added into the MLR to detect the response of the mixed T cells. Results Non-differentiated and osteogenic differentiated BMSCs did not induce proliferation of the allogeneic T cells but both suppressed the proliferation of the T cells mediated by PHA.The TGF-β1 concentrations had significant elevation in the MLR.Anti-TGF-β antibody could counteract the immunosuppressive function of the osteogenic differentiated BMSCs. Conclusion Osteogenic differentiated BMSCs possess low immunogenicity and immunosuppressive property.
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ObjectiveTo investigate the pathogenesy and operation method in patients with ossification of thoracic ligamentum flavum.MethodsThe imaging and clinical data of 56 patients who underwent laminectomy combined with posterolateral fusion were studied retrospectively.The method of laminectomy included enbloc laminectomy and decomposed laminectomy.Postoperative outcomes were evaluated according to a recovery scale in terms of JOA score.ResultsThe patients were followed up for 18-70 (25.00 ± 11.56) months.There were a total of 237 ossified segments in this series,57.4％(136/237)located in lower thoracic segments.According to the configuration of ossification on CT scans,lateral type occurred in 6 patients,diffuse type in 17 patients and thickened nodular type in 33 patients.All patients with lateral type and majority of patients with diffuse type were treated with enbloc laminectomy,and the rate of fineness of postoperative outcome was 83.3％ (5/6),82.4％ ( 14/17 ) respectively.Most of the patients with thickened nodular type were treated with decomposed laminectomy,and the rate of fineness of postoperative outcome was 78.8％ (26/33).Four patients withthickened nodular type were performed with enbloc laminectomy,2 of them resulted in deteriorated myelopathy.Twenty-nine patients with thickened nodular type were performed with decomposed laminectomy,however,only 2 of them resulted in worse outcomes.ConclusionsThe pathogenesis of ossification of thoracic ligamentum flavum is mainly due to the localizedmechanical stress.Laminectomy combining with lateral fusion may be the ideal method for the treatment ofthis condition.Furthermore,enbloc laminectomy is suitable for the patients in lateral type and diffuse type according to the configuration of ossifications.For the thickened nodular type,decomposed laminectomy is favorable.
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Objective To study the results of percutaneous kyphoplasty(PKP) in treating subtle fracture of osteoporotic vertebral body,and to explore the clinical value of PKP in patients with subtle fracture of osteoporotic vertebral body.Methods 52 thoracical vertebral bodies of 35 patients with subtle fracture of osteoporotic vertebral body.Nineteen patients with 30 vertebrae were assigned to group 1 treated by PKP,and sixteen patients with 22 vertebrae were assigned to group 2 treated by conservative therapy.The patients were examined after surgery to ascertain the alleviation of the pain and evaluate the patients' life quality,measuring the heights of vertebrae on the lateral plain films during follow-up.Results Surgery was successful in all cases,no serious complications occurred with PVP.Pain relief was obtained in all of group 1,pain still remained in all 16 patients of group 2 at 1 week after conservative treatment.Improvement was significantly greater in the group 1 than in group 2 at1 week,1 month,3 months,6 months,but no difference at 12 months after treatment (P ＞ 0.05 ).According to ADL,the patients' life quality scores,improvement was significantly greater in the group 1 than in group 2 at1 week,1 month,3 months,6 months,but no difference at 12 months after treatment(P ＞ 0.05 ).The height of the veterbral body showed significant difference at 12 months of follow( P ＜ 0.05).Conclusion PKP was an effective and safe procedure for treating subtle fracture of osteoporotic vertebral body.PKP has satisfactory analgesic effect on subtle fracture of osteoporotic vertebral body and improve quality of patients' life.PKP could effectively prevent collapse of veterbral body.
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Objective To investigate the effect of propofol and isoflurane anesthesia on serum heat shock protein 70 ( HSP70 ) of perioperative patients with brain injury and compare the anesthetic effect of the two narcotic drugs. Methods 30 patients with medium or severe traumatic brain injury,treated by hematoma evacuation operation,were randomly divided into propofol ( n = 15 ) and isoflurane group ( n = 15 ). After anesthesia induction,propofol (target effect concentration of 3 ～ 4 μg/ml ) was intravenously injected and 1.2% isoflurane was inhalated into the patients of the 2 groups,respectively. In addition,vecuronium and fentany were intermittent intravenously injected into patients to maintain the depth of anesthesia. HSP70 in blood of patients were detected before anesthesia induction, 1 h after the dura was opened and 24 h after the operation by ELISA method. Recovery and tracheal extubation time of patients were recorded. Results HSP70 levels in blood of patients in the 2 groups were significantly increased compared with the former time point(P＜0.05 ). HSP70 content in propofol group was significantlyhigher at 1 h after the dura was opened( ( 2.00 ± 0. 24 ) ng/ml, ( 2.19 ± 0.26 ) ng/ml, t = 2. 080, P = 0.047 ) and 24 h after the operation( t=2.086, P=0.046) ,and recovery and tracheal extubation time was shorter compared with the isoflurane group(P＜0. 05). Conclusion Perioperative moderate stress,and early postoperative recovery and extubation can be maintained in patients with traumatic brain injury with profol anesthesia.