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1.
IntroductionVascularized fibular autografts (VFA) are used in the oncologic skeletal reconstructions of long bones, alone or combined with massive bone allografts (MBA). Data regarding the role of imaging in assessing these complex skeletal reconstructions are lacking, and have mainly focused on Computed Tomography (CT). Our aim was to evaluate if early conventional radiography (CR) findings are correlated with the outcome of these skeletal reconstructions.Materials and methodsAll consecutive patients who underwent oncologic resection of lower limbs long bones followed by VFA reconstruction were included in this single-center retrospective study. We compared the CR obtained immediately after surgery with the CR at the 6-month control, as well as the CR at 6 months with the CT at 6 months when available. The following scores were assigned to the VFA: 0 (unchanged), 1 (osteopenia-cortical bone thinning), 2 (increase in bone density-cortical thickening). We then investigated whether this score correlated with the implant outcome within 12 months (optimal integration, suboptimal integration, integration requiring further surgery or lack of integration) using Kaplan-Meier and Cox regression analyses, considering the occurrence of integration and the duration time before the surgical removal of the whole bone reconstruction.ResultsForty-five patients were included (32 men [71.1%], mean age 14.6 years), 26 affected by osteosarcoma, 14 by Ewing sarcoma, 3 by adamantinoma and 2 operated for the failure of previous reconstructions for bone sarcoma. VFA changes on 6-month CR were significantly associated with optimal integration of the implants (log-rank P = 0.0137, multivariate Hazard ratio = 7.62, 95% confidence interval = 1.13–51.25). None of the other clinical and surgical features were associated with the implant outcome. The findings on 6-month CR and CT follow-up were not significantly different. CT at 6 months was available in 36 patients (80.0%).ConclusionThe assessment of VFA morphological changes on CR performed at 6 months can predict the outcome of the skeletal implant. This data should be considered for clinical decision-making, selecting patients requiring additional images (CT), and possible subsequent revision surgical procedures.  相似文献   
2.
目的探讨静脉注射大剂量甲氨蝶呤引起骨肉瘤患者脑白质病的MRI影像学表现。方法选取在本院行大剂量甲氨蝶呤静脉化疗诱发急性脑白质病的4例骨肉瘤患者,出现临床症状时均行颅脑MRI平扫+DWI检查,其中2例行颅脑MRI增强检查。结合患者出现的临床症状,并分析其影像学表现。结果4例脑白质病患者颅脑MRI DWI序列观察到半卵圆中心、侧脑室旁呈高信号,1例患者T2FLAIR图像呈稍高信号,其中2例行颅脑MRI增强检查,病灶未见强化。1~2周后复查颅脑MRI,结果显示DWI的高信号区域缩小、消失。结论颅脑MRI检查对于甲氨蝶呤诱发脑白质病的早期识别具有较大医学价值,有助于准确诊断和及时进行适当治疗,预后良好。  相似文献   
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miR-363-3p has been shown to suppress tumor growth and metastasis in various human cancers. However, the function of miR-363-3p in osteosarcoma (OS) has not been determined. In our study, we found that the expression of miR-363-3p was significantly downregulated in OS tissues compared with adjacent normal tissues. miR-363-3p expression was associated with the poor overall survival rate of OS patients. Moreover, we found that overexpression of miR-363-3p markedly inhibited the proliferation, migration, and invasion of U2OS and MG63 cells. Moreover, we found that SOX4 was a direct target of miR-363-3p in OS cells. Overexpression of miR-363-3p significantly inhibited the expression of SOX4. Expression levels of miR-363-3p and SOX4 were negatively correlated in OS tissues. Finally, we found that restoration of SOX4 attenuated the suppressive effects of miR-363-3p on the proliferation, migration, and invasion of U2OS and MG63 cells. Therefore, our findings demonstrated that miR-363-3p served as a tumor suppressor in OS tissues by targeting SOX4.  相似文献   
5.
Osteosarcoma is the most common primary malignant bone tumor in children and adolescents. This study aimed to explore the effects of long noncoding RNA CAT104 and microRNA-381 (miR-381) on osteosarcoma cell proliferation, migration, invasion, and apoptosis, as well as the underlying potential mechanism. We found that CAT104 was highly expressed in osteosarcoma MG63 and OS-732 cells. Knockdown of CAT104 significantly inhibited OS-732 cell proliferation, migration, and invasion, but promoted cell apoptosis. CAT104 regulated the expression of miR-381, and miR-381 participated in the effects of CAT104 on OS-732 cells. Zinc finger E-box-binding homeobox 1 (ZEB1) was a direct target gene of miR-381, which was involved in the regulatory roles of miR-381 in OS-732 cell proliferation, migration, invasion, and apoptosis, as well as c-Jun N-terminal kinase (JNK) and Wnt/ -catenin pathways. In conclusion, our research verified that suppression of CAT104 exerted significant inhibitory effects on osteosarcoma cell proliferation, migration, and invasion by regulating the expression of miR-381 and downstream ZEB1, as well as JNK and Wnt/ -catenin pathways.  相似文献   
6.
骨肉瘤(osteosarcoma,OS)起源于间叶细胞,是一种最常见于10~30岁青少年的原发恶性骨肿瘤,多见于长骨干骺端,具有侵袭性强且易转移等特点[1-4]。目前主要的治疗包括手术结合新辅助化疗,但是存在耐药、转移、复发等问题[5-6]。已发生肺部等远处转移的骨肉瘤患者几乎不可治愈,5年总体生存率不到30%[7],因此骨肉瘤的早期诊断对于患者的预后至关重要。然而目前骨肉瘤的早期诊断却相对局限。  相似文献   
7.
目的:探讨乳酸链球菌素(nisin)对人骨肉瘤MG63细胞凋亡及其相关的氧化应激机制。方法:乳酸链球菌素单独或联合抗氧化剂N-乙酰-L-半胱氨酸(N-acetyl-L-cysteine,NAC)处理MG63细胞后,采用CCK-8法检测细胞活力;annexin-V/PI双染法检测细胞凋亡;2',7'-二氯荧光素二乙酸酯(2',7'-dichlorofluorescein diacetate,DCFH-DA)荧光探针检测细胞内活性氧簇(reactive oxygen species,ROS)含量;5,5',6,6'-四氯-1,1',3,3'四乙基苯并咪唑羰花青碘化物(5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl benzimidazolyl carbocyanine iodide,JC-1)荧光探针检测线粒体膜电位(mitochondrial membrane potential,MMP)的变化,通过Western blot法检测凋亡相关蛋白Bax、Bcl-2和cleaved caspase-3的水平。结果:乳酸链球菌素呈浓度依赖性降低MG63细胞活力,促进细胞凋亡,上调cleaved caspase-3蛋白水平,增加Bax/Bcl-2蛋白表达的比值,并可诱导细胞内ROS大量生成,降低MMP(P<0.05)。抗氧化剂NAC能显著抑制乳酸链球菌素诱导的MG63细胞凋亡,下调cleaved caspase-3蛋白水平,降低Bax/Bcl-2蛋白表达的比值,并降低细胞内ROS水平,恢复MMP(P<0.05)。结论:乳酸链球菌素可能通过诱导人骨肉瘤细胞氧化应激,进而激活线粒体凋亡通路促进细胞凋亡。  相似文献   
8.
杨华杰  李兰  李彬  张冬  张强 《肿瘤防治研究》2021,48(12):1087-1095
目的 初步探究miR-155在骨肉瘤发生发展及其肺转移进程中的作用,并探讨其靶蛋白及相关机制。方法 通过数据库分析,结合临床组织与细胞样本的相关检测,对骨肉瘤及其肺转移进程中miR-155差异性进行对比分析;应用iTRAQ定量蛋白质组学技术,筛选骨肉瘤及其肺转移进程中miR-155的靶蛋白;在临床组织与细胞样本中,对筛选的miR-155靶蛋白进行验证。结果 miR-155在骨肉瘤组织和肺转移瘤组织中,较对照组均出现明显升高;与人正常成骨细胞相比,人骨肉瘤细胞系miR-155亦出现明显升高。利用iTRAQ实验得到3 714个蛋白,筛选出差异表达蛋白253个,其中上调144个,下调109个。经预测分析和实验验证C/EBP β是miR-155潜在的作用靶蛋白。结论 miR-155在骨肉瘤及其肺转移进程中出现显著升高,C/EBP β是其潜在的作用靶点。  相似文献   
9.
目的探讨七氟醚对骨肉瘤细胞增殖、侵袭、凋亡及化疗敏感性的影响。方法选取骨肉瘤MG63细胞,随机分为四组:对照组、1.7%七氟醚组、3.4%七氟醚组和5.1%七氟醚组,分别为不给予七氟醚、给予1.7%、3.4%和5.1%七氟醚处理。采用MTT法检测细胞增殖,流式细胞术检测细胞凋亡,Transwell细胞侵袭实验检测细胞迁移;给予各组顺铂处理,检测各组细胞凋亡情况。结果培养24、36和72 h的1.7%七氟醚组、3.4%七氟醚组和5.1%七氟醚OD值明显低于对照组(P0.05),培养24、36和72 h的5.1%七氟醚组OD值明显低于1.7%七氟醚组、3.4%七氟醚组(P0.05)。四组细胞凋亡率、细胞迁移数差异无统计学意义。顺铂作用后,1.7%七氟醚组、3.4%七氟醚组和5.1%七氟醚组细胞凋亡率明显低于对照组(P0.05),5.1%七氟醚组细胞凋亡率明显低于1.7%七氟醚组和3.4%七氟醚组(P0.05)。结论七氟醚可抑制骨肉瘤MG63细胞增殖,对细胞迁移、凋亡无明显影响;七氟醚可降低骨肉瘤MG63细胞对顺铂的敏感性。  相似文献   
10.
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