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Rujing Zha Junjie Bu Zhengde Wei Long Han Pengyu Zhang Jiecheng Ren Ji‐An Li Ying Wang Lizhuang Yang Sabine Vollstädt‐Klein Xiaochu Zhang 《Human brain mapping》2019,40(4):1049-1061
The processes involved in value evaluation and self‐control are critical when making behavioral choices. However, the evidence linking these two types of processes to behavioral choices in intertemporal decision‐making remains elusive. As the ventromedial prefrontal cortex (vmPFC), striatum, and dorsolateral prefrontal cortex (dlPFC) have been associated with these two processes, we focused on these three regions. We employed functional magnetic resonance imaging during a delayed discounting task (DDT) using a relatively large sample size, three independent samples. We evaluated how much information about a specific choice could be decoded from local patterns in each brain area using multivoxel pattern analysis (MVPA). To investigate the relationship between the dlPFC and vmPFC/striatum regions, we performed a psychophysiological interaction (PPI) analysis. In Experiment I, we found that the vmPFC and dlPFC, but not the striatum, could determine choices in healthy participants. Furthermore, we found that the dlPFC showed significant functional connectivity with the vmPFC, but not the striatum, when making decisions. These results could be replicated in Experiment II with an independent sample of healthy participants. In Experiment III, the choice‐decoding accuracy in the vmPFC and dlPFC was lower in patients with addiction (smokers and participants with Internet gaming disorder) than in healthy participants, and decoding accuracy in the dlPFC was related to impulsivity in addicts. Taken together, our findings may provide neural evidence supporting the hypothesis that value evaluation and self‐control processes both guide the intertemporal choices, and might provide potential neural targets for the diagnosis and treatment of impulsivity‐related brain disorders. 相似文献
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目的探讨仿生矿化后的丝素电纺复合支架体内修复颅骨缺损的能力。方法利用静电纺丝技术制备丝素电纺支架(非矿化组),通过模拟体液(SBF)浸泡法对支架仿生矿化(矿化组),扫描电镜观察其微观形貌。18只8周龄的雄性SD大鼠购自南京医科大学动物实验中心,采用随机数字表示法分为3组,分别为矿化组、非矿化组和对照组,每组6只。构建SD大鼠颅骨缺损模型,在直径为5 mm的骨缺损区分别植入矿化组及非矿化组支架,对照组不作处理,分别于术后4、8周取材,通过微计算机断层扫描技术(micro-CT)、苏木精-伊红(HE)及马松染色(Masson染色)比较评估不同支架的体内骨再生情况。应用GraphPad Prism 8统计软件分析,采用单因素方差分析。结果扫描电镜结果显示仿生矿化后的丝素电纺支架表面形成明显的羟基磷灰石矿化层。动物实验结果显示,术后4周和8周,通过对CT三维重建、HE及Masson染色的观察以及对骨体积分数(BV/TV),骨小梁数(Tb.N),骨小梁厚度(TB.Th)和骨小梁间隙(TB.Sp)定量指标的分析结果显示,在矿化组和非矿化组均能观察到新骨的形成,且矿化组的修复效果均优于非矿化组,差异有统计学意义[矿化组、非矿化组及对照组BV/TV在4周时分别为(22.880±2.324)、(12.600±1.965)、(4.967±1.580)%,F=61.838,P<0.05,8周时分别为(45.770±4.433)、(29.400±4.086)、(19.310±2.272)%,F=38.686,P<0.05;Tb.N在4周时分别为(0.029±0.001)、(0.019±0.003)、(0.008±0.003)mm-1,F=52.890,P<0.05,8周时分别为(0.053±0.002)、(0.037±0.003)、(0.023±0.001)mm-1,F=171.433,P<0.05;TB.Sp在4周时分别为(10.810±0.179)、(11.350±0.098)、(11.730±0.163)μm,F=27.655,P<0.05,8周时分别为(8.792±0.175)、(10.060±0.339)、(11.150±0.275)μm,F=56.807,P<0.05]。结论仿生矿化后的丝素电纺复合支架能有效促进骨再生,有望用于骨组织工程。 相似文献
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目的:检测Wnt7a在肝癌中的表达,分析Wnt7a对肝癌细胞活性、凋亡、迁移及侵袭的影响,探讨Wnt7a在肝癌中的作用。方法:分别采用免疫组织化学染色和Western blot检测组织和细胞系中Wnt7a的表达情况;Hep3B细胞经人重组Wnt7a蛋白(rWnt7a)处理后,MTT法检测细胞活性改变,流式细胞仪检测细胞凋亡变化,Transwell分析细胞迁移及侵袭能力变化。结果:相对于癌旁组织,肿瘤组织低表达Wnt7a蛋白;经rWnt7a处理后,Hep3B细胞活性降低、细胞凋亡增多且迁移与侵袭能力下降。结论:Wnt7a蛋白能抑制Hep3B细胞生长、迁移与侵袭能力,可能在肝癌中发挥抑癌作用。 相似文献
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Karasu Buğra Gunay Betul Onal 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(1):99-106
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate central macular thickness (CMT), subfoveal choroidal thickness (SFCT), and visual outcomes following different... 相似文献
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Bo Cai Ping Ma Pengpeng Ding Di-Wen Sun Qingao Bu Jun Zhang 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2020,128(3):260-269
Low Foxp3+ regulatory T-cell (Treg) presence in the tumor-infiltrating lymphocytes (TILs) is considered favorable in breast cancer, and numerous CD25-targeting agents have been applied in the attempt to remove Foxp3+ Treg cells, which typically present CD4+CD25+/hi surface phenotype. However, CD25 is not Treg-exclusive and can be upregulated by effector T cells. Hence, CD25 depletion may cause the elimination of activated T cells that are responding to tumor-specific antigens. In this study, the composition and function of CD4+CD25+ cells inside the microenvironment of triple-negative breast carcinoma (TNBC) were investigated. Directly ex vivo, the Foxp3+ Treg cells represented a minor subset in total CD4+CD25+ TILs. Significant differences were observed in the expression of Treg-associated molecules between CD4+CD25+Foxp3+ TILs and CD4+CD25+Foxp3− TILs. While both the CD4+CD25+Foxp3+ and the CD4+CD25+Foxp3− TILs could express CTLA-4 and LAG-3, the expression levels were significantly higher in CD4+CD25+Foxp3+ TILs than in CD4+CD25+Foxp3− TILs. Upon TCR stimulation, the expression of TGF-beta was significantly higher in CD4+CD25+Foxp3+ TILs, while the expression of IL-10 was significantly higher in CD4+CD25+Foxp3− TILs. These differences were conserved in the blood counterparts of these cells. Interestingly, the level of CD25+Foxp3+ cells in circulating CD4+ T cells was positively correlated with the level of CD25+Foxp3+ cells in CD4+ TILs, but the level of CD25+Foxp3− cells in circulating CD4+ T cells was not associated with the level of CD25+Foxp3- cells in CD4+ TILs. Th17-polarizing medium could readily remodel CD4+CD25+Foxp3−, but not CD4+CD25+Foxp3+, T cells into RORgammat and IL-17-expressing T cells, demonstrating stronger plasticity of the former subset. Together, these data demonstrated that the CD4+CD25+ TILs were composed of distinctive Foxp3− and Foxp3+ cells, with the former representing the major subset. The antigen specificity and effector molecule expression of the CD4+CD25+Foxp3− thus require further analyses. 相似文献