寰枢椎后路柔性固定的生物力学研究

目的分析细棒、PEEK棒固定对寰枢关节稳定性的影响。方法采用6具新鲜成人枕骨(occipital bone,Oc)~颈椎C4节段进行测试,模拟以下手术及固定状态:①完整状态;②损伤状态:枢椎齿状突II型骨折;③坚强固定:寰枢椎均采用普通椎弓根螺钉固定,直径3.5 mm钛棒连接;④PEEK棒:直径3.5 mm的PEEK棒连接;⑤细棒:直径2.0 mm钛棒连接。采用重复测量实验设计,在完整、损伤和不同的固定状态下,通过脊柱试验机对标本分别施加1.5 N·m的前屈/后伸、左/右侧弯和左/右轴向旋转的纯力偶矩。采用Optotrak三维运动测量系统连续采集标本运动,分析寰枢椎之间角度运动范围和中性区。结果采用直径3.5 mm的钛棒,2.0 mm的细棒以及3.5 mm的PEEK棒固定后,在前屈、后伸、侧弯和旋转方向上均显著减小了固定节段的运动范围(P<0.05)。直径3.5 mm和2.0 mm的棒固定后的运动范围,在各个方向上无显著性差异。PEEK棒固定的运动范围仅在侧弯方向上大于坚强固定(P=0.005),其他方向无显著性差异。3种固定方式在屈伸、侧弯和旋转方向上均显著减小了固定节段的中性区(P<0.05)。各种固定方式之间相比较,无显著性差异(P>0.05)。结论在寰枢关节采用直径2.0 mm的细棒固定,与坚强固定的稳定性相当。采用直径3.5 mm的PEEK棒固定,在前屈、后伸、旋转方向上与坚强固定的稳定性相当,在侧弯方向上弱于坚强固定。     

Genomic variants within chromosome 14q32.32 regulate bone mass through MARK3 signaling in osteoblasts

Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.     

Efficacy and safety of transjugular intrahepatic portosystemic shunt (TIPS) created using covered stents of different diameters: A systematic review and meta-analysis

PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored.     

SLC及其受体CCR7与Ⅰ期非小细胞肺癌淋巴结微转移的相关性

目的 探讨溶质载体蛋白（SLC）及其受体趋化因子受体7（CCR7）与I期非小细胞肺癌（NSCLC）淋巴结微转移的相关性。方法 选取2019年1月~2020年3月于我院就诊的I期NSCLC患者127例为研究对象，按照淋巴结微转移情况分为对照组92例和转移组35例，所有患者入院后均通过根治术切除病灶，通过免疫组化方式检测病灶中SLC7A11及CCR7含量，并收集患者临床资料、实验室检查资料及影像学检查资料。通过Logistic回归分析评价SLC7A11及CCR7与淋巴结微转移之间的关系。最后通过建立ROC曲线分析两者及其联合检测对NSCLC患者微淋巴结转移的预测价值。结果 两组患者SLC7A11及CCR7表达水平存在显著差异（P＜0.05）。转移组患者病灶直径、支气管受累及TLG显著高于对照组（P＜0.05）。病灶直径（OR=49.254,95%CI=11.062~507.604）是影响NSCLC淋巴结微转移的独立危险因素（P＜0.05）。SLC7A11（OR=8.622）及CCR7（OR=8.709）表达水平是影响NSCLC淋巴结微转移的独立因素（P＜0.05）。SLC7A11、CCR7及联合诊断对NSCLC淋巴结微转移具有较好的检测价值（均P＜0.05）。联合检测特异度显著高于 SLC7A11及CCR7单独检测（2=7.292，15.125；均P＜0.01）。结论 SLC家族的中SLC7A11及其受体CCR7与NSCLC患者微淋巴结转移显著相关。     

A Priori Subcell Limiting Approach for the FR/CPR Method on Unstructured Meshes

A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on modal energy coefficients is proposed to detect troubled cells, where discontinuities exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR method. Numerical investigations show that the proposed subcell limiting strategy on unstructured quadrilateral meshes is robust in shock-capturing.     

Radiomics model based on preoperative gadoxetic acid-enhanced MRI for predicting liver failure

BACKGROUND Postoperative liver failure is the most severe complication in cirrhotic patients with hepatocellular carcinoma(HCC) after major hepatectomy. Current available clinical indexes predicting postoperative residual liver function are not sufficiently accurate.AIM To determine a radiomics model based on preoperative gadoxetic acid-enhanced magnetic resonance imaging for predicting liver failure in cirrhotic patients with HCC after major hepatectomy.METHODS For this retrospective study, a radiomics-based model was developed based on preoperative hepatobiliary phase gadoxetic acid-enhanced magnetic resonance images in 101 patients with HCC between June 2012 and June 2018. Sixty-one radiomic features were extracted from hepatobiliary phase images and selected by the least absolute shrinkage and selection operator method to construct a radiomics signature. A clinical prediction model, and radiomics-based model incorporating significant clinical indexes and radiomics signature were built using multivariable logistic regression analysis. The integrated radiomics-based model was presented as a radiomics nomogram. The performances of clinical prediction model, radiomics signature, and radiomics-based model for predicting post-operative liver failure were determined using receiver operating characteristics curve, calibration curve, and decision curve analyses.RESULTS Five radiomics features from hepatobiliary phase images were selected to construct the radiomics signature. The clinical prediction model, radiomics signature, and radiomics-based model incorporating indocyanine green clearance rate at 15 min and radiomics signature showed favorable performance for predicting postoperative liver failure(area under the curve: 0.809-0.894). The radiomics-based model achieved the highest performance for predicting liver failure(area under the curve: 0.894; 95%CI: 0.823-0.964). The integrated discrimination improvement analysis showed a significant improvement in the accuracy of liver failure prediction when radiomics signature was added to the clinical prediction model(integrated discrimination improvement = 0.117, P =0.002). The calibration curve and an insignificant Hosmer-Lemeshow test statistic(P = 0.841) demonstrated good calibration of the radiomics-based model. The decision curve analysis showed that patients would benefit more from a radiomics-based prediction model than from a clinical prediction model and radiomics signature alone.CONCLUSION A radiomics-based model of preoperative gadoxetic acid–enhanced MRI can be used to predict liver failure in cirrhotic patients with HCC after major hepatectomy.     

2013-2017年我国四种恶性肿瘤住院费用水平及结构变动度分析

背景　恶性肿瘤给家庭、社会带来了沉重的医疗、经济负担，极易导致部分家庭“因病致贫”或放弃治疗，目前相关研究多集中于单一病种、分散地域的研究，仍缺乏对于全国范围与多病种恶性肿瘤住院费用变化及结构构成的考量。目的　分析2013-2017年我国4种恶性肿瘤住院费用水平以及影响住院费用的主要项目和结构变动情况，为控制医疗费用上涨、深化新医改提供参考依据。方法　本研究数据来源于《2014中国卫生和计划生育统计年鉴》《2015中国卫生和计划生育统计年鉴》《2016中国卫生和计划生育统计年鉴》《2017中国卫生和计划生育统计年鉴》以及《2018中国卫生健康统计年鉴》，样本跨度为2013-2017年。统计“30种疾病人均住院费用”中的胃恶性肿瘤、肺恶性肿瘤、食管恶性肿瘤以及膀胱恶性肿瘤的数据，4种恶性肿瘤的人均住院费用包括药费、检查费、治疗费、手术费和手术材料费。2019年4-8月，采用结构变动度法分析我国2013-2017年4种恶性肿瘤的住院费用的结构变动情况〔结构变动值（VSV）、结构变动度（DSV）、结构变动贡献率〕。结果　2013-2017年，4种恶性肿瘤的人均住院费用逐年上升，其中胃恶性肿瘤的人均住院费用始终最高，且肺恶性肿瘤的人均住院费用上升幅度最大。2013-2017年，在4种恶性肿瘤住院各项费用的占比中，药费占比最高且总体逐年下降。从4种恶性肿瘤住院各项费用的实际变化来看，药费在2013-2014年有所上升，2014-2017年逐年下降；检查费在2013-2014年下降，2014-2017年缓慢上升；手术费与手术材料费在2013-2017年逐年上升。2013-2017年，在4种恶性肿瘤住院各项费用中均是药费的VSV最大；4种恶性肿瘤药费、检查费的VSV均呈负向变化，手术费和手术材料费的VSV均呈正向变化，治疗费的VSV增减均不明显。2013-2017年，4种恶性肿瘤住院费用的DSV从大到小依次为肺恶性肿瘤、胃恶性肿瘤、食管恶性肿瘤、膀胱恶性肿瘤。2013-2017年，4种恶性肿瘤住院各项费用中均是药费的结构变动贡献率最大，治疗费的结构变动贡献率最小；除药费外，胃恶性肿瘤、肺恶性肿瘤住院各项费用中均是手术材料费和手术费的结构变动贡献率次之，食管恶性肿瘤住院各项费用中手术费、检查费的结构变动贡献率次之，膀胱恶性肿瘤住院各项费用中检查费、手术材料费的结构变动贡献率次之。结论　2013-2017年我国4种恶性肿瘤手术费的结构变动贡献率虽然较为理想，但药费、治疗费仍是住院费用结构的重点调整对象；同时为有效降低恶性肿瘤的人均住院费用，应当加强控制手术材料费与检查费；而胃恶性肿瘤与肺恶性肿瘤患者的疾病经济负担严重，若要缓解应加强疾病的早期预防与住院费用管控。     

Utility of Tissue Similarity Maps Based on Relative Cerebral Blood Volume for Grading Gliomas as Validated by Histological Results

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