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1.
Obesogens are a subset of endocrine disruptor chemicals (EDCs) that cause obesity. The typical EDC 4-nonylphenol (4-NP) has been identified as an obesogen. However, the in vitro effects of 4-NP on adipogenesis remain unclear. In this study, 3T3-L1 preadipocytes and C3H/10T1/2 mesenchymal stem cells (MSCs) were used to investigate the influence of 4-NP on adipogenesis. The differentiation protocols for 3T3-L1 preadipocytes and C3H/10T1/2 MSCs took 8 and 12 days, respectively, beginning at Day 0. In differentiated 3T3-L1 preadipocytes, 20 μM 4-NP decreased cell viability on Days 4 and 8. Exposure to 4-NP inhibited triglyceride (TG) accumulation and adipogenic marker expression on Days 0–8, but the inhibitory effects were weaker on Days 2–8. The protein expression of pSTAT3 or STAT3 decreased on Days 0–8 and 2–8. Conversely, 4-NP promoted TG accumulation and the adipogenic marker expression in C3H/10T1/2 adipocytes. The opposing effects were attributed to physiological differences between the two cell lines. The 3T3-L1 preadipocytes are dependent on mitotic clonal expansion (MCE) to drive differentiation, while C3H/10T1/2MSCs and human preadipocytes are not. Additionally, 4-NP downregulated β-catenin expression in C3H/10T1/2 adipocytes. Accordingly, we hypothesized that 4-NP promotes adipogenesis. The role of the canonical Wnt pathway in the promotion of adipogenesis by 4-NP requires further validation. This study provides new insights into the mechanisms and appropriate risk management of 4-NP.  相似文献   
2.
《Vaccine》2022,40(49):7065-7072
BackgroundUnadjuvanted A/H7N9 vaccines are poorly immunogenic. The immune response is improved with the addition of MF59, an oil-in-water adjuvant. However, the cellular immunologic responses of MF59-adjuvanted A/H7N9 vaccine are not fully understood.Methods37 participants were vaccinated with 2 doses of 2013 influenza A/H7N9 vaccine (at Days 1 and 21) with or without MF59 and enrolled in an immunology substudy. Responses were assessed at multiple timepoints (Days 0, 8, 21, 29, and 42) for hemagglutination inhibition (HAI) and neutralizing antibody (Neut) assays, memory B cell responses by enzyme-linked ImmunoSpot; circulating follicular helper T cells (cTFH) and CD4 + T cells by intracellular cytokine staining.ResultsMF59-adjuvanted influenza A/H7N9 vaccine induced significantly higher hemagglutination inhibition (HAI) and neutralizing antibody (Neut) responses when compared to unadjuvanted vaccine. The adjuvanted vaccine elicited significantly higher levels of Inducible T-cell Co-Stimulator (ICOS) expression by CXCR3+CXCR5+CD4+ cTFH cells, compared to unadjuvanted vaccine. The magnitude of increase in cTFH cells (from baseline to Day 8) and in IL-21 expressing CD154+CD4+ T cells (from baseline to Days 8 and 21) correlated with HAI (at Day 29) and Neut antibody (at Days 8 and 29) titers. The increase in frequency of IL-21 expressing CD154+CD4+T cells (from baseline to Day 21) correlated with memory B cell frequency (at Day 42).ConclusioncTFH activation is associated with HAI and Neut responses in recipients of MF59-adjuvanted influenza A/H7N9 vaccine relative to unadjuvanted vaccine. Future studies should focus on optimizing the cTFH response and use cTFH as an early biomarker of serological response to vaccination.This trial was registered at clinicaltrials.gov, trial number NCT01938742.  相似文献   
3.
目的 研究Dhcr24在有氧运动改善心肌梗死(myocardial infarction,MI)后心肌细胞功能中的潜在作用及分子机制。方法 通过H2O2建立心肌细胞(H9C2)凋亡模型,并通过AMPK激动剂AICAR来模拟心肌细胞的运动效果。通过流式细胞术和TUNEL检测心肌细胞凋亡水平;通过Western blot检测心肌细胞中凋亡相关蛋白Bcl-2、Bax和Dhcr24的表达水平;通过RT-qPCR检测细胞中Dhcr24 mRNA的水平。结果 与对照组相比,H2O2诱导的心肌细胞凋亡率增加、TUNEL阳性粒子数升高、抗凋亡蛋白Bcl-2水平降低、促凋亡蛋白Bax水平升高、Dhcr24水平降低。与H2O2诱导的心肌细胞相比,AMPK激活剂AICAR处理后,心肌细胞凋亡率、TUNEL阳性粒子数降低、Dhcr24水平升高。在H2O2和AICAR共同处理的心肌细胞中敲低Dhcr24,降低的细胞凋亡率、TUNEL阳性粒子数得到逆转。结论 有氧运动对H2O2诱导的心肌细胞凋亡具有明显保护作用,可能与其上调Dhcr24表达有关。  相似文献   
4.
目的 汉化护生临床实践反思问卷,检验其在实习护生中的信度和效度。 方法 基于Brislin模型对英文版临床实践反思问卷进行翻译。采用一般资料调查表、中文版护生临床实践反思问卷和反思功能问卷对550名实习护生进行调查,以检验其信效度。 结果 中文版护生临床实践反思问卷包括专业能力、内部动机来源、基于反思的自我管理、具有挑战性的临床情境、动态的组织氛围和动态的职业发展6个维度,共36个条目。探索性因子分析共提取6个公因子,累计方差贡献率为70.099%;验证性因子分析结果显示,χ2/df=1.292,RMSEA=0.033,CFI=0.977,TLI=0.974。量表Cronbach′s α系数为0.961,各维度Cronbach′s α系数为0.870~0.949,量表水平的平均内容效度为0.983,折半信度为0.853,重测信度为0.934。 结论 中文版护生临床实践反思问卷具有较好的信度和效度,可用于评估我国实习护生在临床实践中的反思能力。  相似文献   
5.
《Cirugía espa?ola》2022,100(12):772-779
IntroductionDistance from anal verge of rectal tumors and their anatomical relationships contribute to determine the multidisciplinary therapeutic strategy based on the combination of radio-chemotherapy and radical surgery. Our aims are to investigate which is the most accurate method for the preoperative measuring of the distance from the anal verge in rectal tumors and if the pelvic MRI can substitute the classical instrumental methods.MethodsProspective study of diagnostic precision between flexible colonoscopy (FC), preoperative rigid rectosigmoidoscopy (pRR) and pelvic MRI in patients scheduled to radical surgery. Rigid intraoperative rectoscopy (iRR) was considered the reference test. The correlations between the different techniques and their determination coefficient as well as the intraclass correlation coefficient and the degree of agreement between the different tests were analyzed.Results96 patients (65% males), mean age (SD): 68 (14.1) years were included. 72% received neoadjuvant treatment. The mean distance to the anal margin measured by FC = 103.5 mm, was significantly greater than others, which had similar values: pRR = 81.1; MRI = 77.4; iRR = 82.9 mm (P < .001). A significant intraclass correlation was observed and there was high agreement between all pre- and intraoperative measurements except for the performed by FC, which overestimated the results. MRI provided more individualized and accurate information.ConclusionsThere is variability between the measurement methods, being colonoscopy the least reliable. MRI offers objective, comparable, accurate and individualized values that can replace those obtained by pRR for tumors of any location in the rectum.  相似文献   
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7.
江媛  杨青淑  王婧  杨成金  黄林芳  杨燕  段宝忠 《中草药》2021,52(13):4014-4022
目的获取毛重楼Parismairei叶绿体基因组信息特征并对其系统位置进行研究。方法采用Illumination测序技术对毛重楼叶绿体基因组进行测序,对其进行组装、注释和特征分析,并构建最大似然(maximumlikelihood,ML)系统发育树。结果毛重楼叶绿体基因组大小为163 918 bp,总GC含量为37.05%,大单拷贝区(large single-copy,LSC)、小单拷贝区(smallsingle-copyregion,SSC)分别为84173、13054bp,反向互补重复区(invertedrepeats,IR)大小为33296bp,共编码113个基因,包括79个蛋白质编码基因,30个t RNA基因和4个r RNA基因。在系统进化树中,重楼属Paris L.与藜芦科(Melanthiaceae Batsch ex Borkh.)关系较近,与百合科(Liliaceae Juss.)关系较远。结论 LSC区和SSC区序列变异高于IR区;相较于重楼属,毛重楼与蚤休组的亲缘关系最近,应将毛重楼归属为蚤休组;相较于百合科,毛重楼与藜芦科藜芦属亲缘关系更近,应将蚤休组从百合科中独立,归属为藜芦科。  相似文献   
8.
In our paper, the magneto-optical properties of a dichroic cholesteric liquid crystal layer with large values of magneto-optical parameter g and low values of dielectric permittivity were investigated. The solutions of the dispersion equation and their peculiarities were investigated in detail. The specific properties of reflection, transmission, absorption, rotation, ellipticity spectra and also the spectra of ellipticity and azimuth of eigen polarization were investigated. The existence of a tunable linear and nonreciprocal transmission band was shown.  相似文献   
9.
10.
雒军  王引权  吴国泰  王艳  王振恒  荔淑楠  彭桐 《中草药》2021,52(21):6663-6668
目的 分析当归Angelica sinensis中阿魏酸和藁本内酯等主要有效成分在其根部的积累规律和转化机制。方法 采用HPLC法测定不同生长期当归根部中阿魏酸、阿魏酸松柏酯和藁本内酯等8种苯酞类挥发油成分的含量,结合体外转化研究成果进行分析。结果 阿魏酸和阿魏酸松柏酯含量从苗期到根膨大期沿着相同的方向不断增加,而从根膨大期到收获期分别逐渐降低和升高,朝2个相反的方向变化,提示在当归体内可能存在阿魏酸和松柏醇转化为阿魏酸松柏酯的过程。藁本内酯和5种转化产物含量总体随生长期呈现上升趋势,尤其从根膨大期到成药期增长速度极快,符合成药期特性;藁本内酯含量远远大于其他6种苯酞类转化产物洋川芎内酯I、洋川芎内酯H、阿魏酸松柏酯、洋川芎内酯A、正丁基苯酞、欧当归内酯的含量,提示在当归活体内藁本内酯的转化程度不高,具体转化机制有待进一步研究。结论 阿魏酸和藁本内酯在不同生长期具有不同的积累和转化规律,可为当归药材生产、炮制和质量评价提供理论支持。  相似文献   
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