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IntroductionAlthough hyperferritinemia may reflect the inflammatory status of patients with non-alcoholic fatty liver disease (NAFLD), approximately 33% of hyperferritinemia cases reflect real hepatic iron overload.AimTo evaluate a non-invasive method for assessing mild iron overload in patients with NAFLD using 3T magnetic resonance imaging (MRI) relaxometry, serum hepcidin, and the expression of ferritin subunits.MethodsThis cross-sectional study assessed patients with biopsy-proven NAFLD. MRI relaxometry was performed using a 3T scanner in all patients, and the results were compared with iron content determined by liver biopsy. Ferritin, hepcidin, and ferritin subunits were assessed and classified according to ferritin levels and to siderosis identified by liver biopsy.ResultsA total of 67 patients with NAFLD were included in the study. MRI revealed mild iron overload in all patients (sensitivity, 73.5%; specificity, 70%). For mild (grade 1) siderosis, the transverse relaxation rate (R2*) threshold was 58.9 s?1 and the mean value was 72.5 s?1 (SD, 33.9), while for grades 2/3 it was 88.2 s?1 (SD, 31.9) (p < 0.001). The hepcidin threshold for siderosis was > 30.2 ng/mL (sensitivity, 87%; specificity, 82%). Ferritin H and ferritin L subunits were expressed similarly in patients with NAFLD, regardless of siderosis. There were no significant differences in laboratory test results between the groups, including glucose parameters and liver function tests.ConclusionsMRI relaxometry and serum hepcidin accurately assessed mild iron overload in patients with dysmetabolic iron overload syndrome.  相似文献   
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目的 探讨低强度脉冲超声(LIPUS)联合脂肪间充质干细胞(ADSCs)源性外泌体(ADSCs-Exos)对内皮细胞血管生成能力的影响。方法 取SD大鼠腹股沟处脂肪,采用酶消化法分离培养得ADSCs,并对ADSCs表面分子进行鉴定。收集第3代ADSCs上清液提取外泌体,通过透射电子显微镜(TEM)、纳米粒子跟踪分析(NTA)、蛋白免疫印迹技术(Western blot)鉴定。将人脐静脉内皮细胞(HUVECs)按照不同处理方式分为:对照组、外泌体组、LIPUS组及LIPUS+外泌体组,采用CCK-8实验、划痕实验及小管形成实验检测不同处理对HUVECs增殖、迁移及成管能力的影响。。结果 ADSCs-Exos为形态一致的茶托样囊泡,表达标志性蛋白CD9和Tsg101,所测样品直径97.8%集中在118.8±80.8nm,证明提取的样品直径符合外泌体大小。(此特征表现为什么?)。CCK-8实验显示LIPUS+外泌体组OD值为1.882±0.138,均明显高于外泌体组、LIPUS组及对照组(0.646±0.034、0.631±0.027、0.462±0.036),差异均有统计学意义(均P<0.05)。划痕实验显示LIPUS+外泌体组细胞迁移率为(87.7±4.5)%,均明显高于外泌体组(43.0±5.1)%、LIPUS组(34.7±2.3)%及对照组(25.1±2.0)%,差异均有统计学意义(均P<0.05)。小管形成实验 显示LIPUS+外泌体组HUVECs成管能力均高于其他组,差异均有统计学意义(均P<0.05)。结论 LIPUS联合ADSCs-Exos可有效促进血管内皮细胞的增殖、迁移及成管,增强血管生成能力。  相似文献   
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目的:探讨脉冲电磁场通过Wntβ-catenin信号转导机制改善膝骨关节炎大鼠炎症反应的机制。方法:选取90只SD大鼠,均分为正常组、模型组和脉冲电磁场组,除正常组,其余各组均构建膝骨关节炎模型。测定各组大鼠局部皮温、膝关节周径和Lequesne MG评分;采取甲苯胺蓝染色进行Mankins评分;Western Blot检测软骨细胞凋亡调控蛋白Caspase-3和Caspase-8水平;ELISA法测定滑膜IL-1β、MMP-13、TNF-α表达;并检测Wnt和β-catenin mRNA和蛋白表达差异;检测大鼠线粒体膜电位。结果:与正常组相比,模型组大鼠膝关节局部皮温、膝关节周径、Lequesne MG评分、Mankins评分、Wntβ-catenin表达以及滑膜IL-1β、MMP-13、TNF-α水平均上调(P<0.05);与模型组比较,脉冲电磁场组膝关节周径、Lequesne MG评分,Mankins评分、Wntβ-catenin表达以及滑膜IL-1β、MMP-13、TNF-α水平均下调(P<0.05)。相较于正常组,其余2组的关节软骨线粒体膜电位均有所下调。与模型组相比,脉冲电磁场组线粒体膜电位有所上调,脉冲电磁场组优于模型组。结论:脉冲电磁场能抑制膝骨关节炎模型大鼠炎症反应,有效修复软骨损伤,降低炎症因子表达,抑制Wntβ-catenin信号转导。  相似文献   
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《Dental materials》2022,38(6):924-934
ObjectivesTo study the oxide layer stability of certified dental implants of system "P", made based on TiO2 alloy with carbon coating. To perform a comparative statistical analysis of the obtained data with the available data for the dental implants of systems "A" and "B".MethodsX-ray microtomography and X-ray fluorescence analysis were used to study soft tissue biopsy specimens. Supernatants were studied by dynamic light scattering and transmission electron microscopy when simulating free emission of nanoscale metal oxide particles from the surface of dental implants as well as when simulating physical loading. A comparative analysis of three parameters of nanoscale particles was performed by statistical data analysis. The surface of the "P" system dental implant with surface treatment was analyzed by scanning electron microscopy.ResultsBoth free emission of nanoscale oxide layer particles and yield of nano- and microscale particles during simulation of physical load were confirmed. Statistically significant differences were noted in a comparative analysis of the size and frequency of occurrence of these particles in the supernatants obtained from the surfaces of three dental implant systems. The elemental composition of the particles and the composition and structure of the "P" system dental implants themselves were analyzed.SignificanceThe developed method of dynamic light scattering can be used to compare the stability of the oxide layer of standardized medical products manufactured on the basis of the TiO2 alloy.  相似文献   
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目的 调查徐州市直属小学学生近视现状,分析教室光环境及学龄对儿童视力的影响。方法 采用整群抽样方法,运用标准对数视力表对直属小学学生进行视力检测;随机抽取4所学校,使用TES-1332A照度计测定教室光环境;计量资料采用t检验或方差分析;计数资料采用χ2检验,等级资料采用秩和检验分析其统计学差异。结果 2018年徐州市小学生近视检出率总体为49.84%(男生45.81%,女生53.88%),女生高于男生(χ2=52.001,P<0.05),且重度近视检出率更高(Z=7.795,P<0.05)。市直属小学生近视检出率54.18%,县区直属小学46.45%,市区高于县区(χ2=47.247,P<0.05)。不同年级近视发生情况不同,二~六年级近视检出率分别为36.03%,40.5%,48.45%,58.77%,65.4%,高年级近视发生率高于低年级(χ2趋势=384.766,P<0.05),且重度近视高于低年级(χ2=742.673,P<0.05)。各检测小学不同楼层间教室黑板以及桌面照度不同 (F=3.894,P<0.05) ,但均符合国家标准。结论 徐州市直属小学学生近视检出率较高,并随学龄延长而加重,女生更严重;监测学校教室光环境符合要求。改善和保护学生视力除了保障教室光环境合格和定期监测外,应进一步探讨影响学生视力的其他因素,共同促进学生视力健康。  相似文献   
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We read with interest the commentary by Skeldon and Dijk about our article “Weekly, seasonal and chronotype-dependent variation of dim light melatonin onset.” The discussion points raised by Skeldon and Dijk are currently among the most hotly debated in human circadian science. What external factors determine human phase of entrainment? How great is the contribution of natural versus artificial light and sun time versus social time? Our intra-individual data add to the still limited evidence from field studies in this matter. In their commentary, Skeldon and Dijk formulate two either-or hypotheses, postulating that humans entrain either solely to the natural light-dark cycle (sun time referenced by midday) (H1) or solely to the light selected by local clock time and social constraints (H2). Neither hypothesis accounts for the effect of season on human light exposure. We interpreted our findings along more complex lines, speculating that the 1-h earlier melatonin rise in summer found in our sample is likely the combined result of daylight saving time (DST)-induced behavioral advances and a stronger natural zeitgeber in summer (light exposure determined by social and seasonal factors, Horiginal). Here, we show how the criticism by Skeldon and Dijk is based on two sentences quoted out of context (misrepresenting our hypothesis as H1) and that their hypothesis H2 leaves out important seasonal components in light exposure.  相似文献   
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BackgroundThere is increasing research interest regarding physical activity behavior among persons with multiple sclerosis (MS), yet there is little known about physical activity and its correlates in Black persons with MS.ObjectiveThis cross-sectional study assessed associations among social cognitive theory (SCT) variables and device-measured and self-reported physical activity in samples of Black and White persons with MS.MethodsParticipants included 67 Black and 141 White persons with MS who wore an ActiGraph accelerometer on a belt around the waist measuring moderate-to-vigorous physical activity (MVPA) for seven days and completed a battery of questionnaires. Questionnaires included demographic and clinical characteristics, leisure-time exercise, exercise self-efficacy, overcoming barriers self-efficacy, function, social support, exercise outcome expectations, and goal setting and planning.ResultsBlack participants with MS engaged in significantly less MVPA, but not sedentary behavior or light physical activity, than the White participants with MS. Black participants further had significantly lower levels of exercise self-efficacy and outcome expectations than the White sample. All SCT correlates were significantly correlated with self-reported physical activity, but only exercise and barriers self-efficacy, perceived function, and exercise goal setting were associated with device-measured MVPA. The difference in physical activity between Black and White participants with MS was accounted for by differences in exercise self-efficacy and outcome expectations.ConclusionsResearchers should consider developing behavioral interventions that target exercise self-efficacy and outcome expectations as SCT variables for increasing physical activity in Black persons with MS.  相似文献   
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