2.Thymic epithelial cell development and differentiation: cellular and molecular regulation.
Lina SUN ; Haiying LUO ; Hongran LI ; Yong ZHAO
Protein & Cell 2013;4(5):342-355
Thymic epithelial cells (TECs) are one of the most important components in thymic microenvironment supporting thymocyte development and maturation. TECs, composed of cortical and medullary TECs, are derived from a common bipotent progenitor, mediating thymocyte positive and negative selections. Multiple levels of signals including intracellular signaling networks and cell-cell interaction are required for TEC development and differentiation. Transcription factors Foxn1 and autoimmune regulator (Aire) are powerful regulators promoting TEC development and differentiation. Crosstalks with thymocytes and other stromal cells for extrinsic signals like RANKL, CD40L, lymphotoxin, fibroblast growth factor (FGF) and Wnt are also definitely required to establish a functional thymic microenvironment. In this review, we will summarize our current understanding about TEC development and differentiation, and its underlying multiple signal pathways.
Cell Communication
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genetics
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Cell Differentiation
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Epithelial Cells
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cytology
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metabolism
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Forkhead Transcription Factors
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genetics
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metabolism
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Humans
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Signal Transduction
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genetics
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Thymocytes
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cytology
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metabolism
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Thymus Gland
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cytology
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growth & development
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Transcription Factors
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genetics
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metabolism
3.Assessment of high-resolution MR vessel wall imaging for plaques characteristics changes after lipid-lowering therapy in acute stroke patients
Yingshuai ZHANG ; Zhigang PENG ; Xinju GAO ; Hongran LIU ; Cuicui LIU ; Xiaona LI
Journal of Practical Radiology 2024;40(6):880-883,887
Objective To evaluate the effect of standardized lipid-lowering therapy in acute stroke patients via high-resolution magnetic resonance vessel wall imaging(HRMR-VWI)to follow-up the characteristics changes of intracranial atherosclerotic plaques.Methods Twenty-two acute stroke patients(65 plaques)were enrolled,and their clinical and imaging data were collected on admission and after standardized lipid-lowering therapy(355-370 days).Diffusion weighted imaging(DWI),three-dimensional time of flight magnetic resonance angiography(3D-TOF-MRA),and HRMR-VWI were performed in all patients.According to the changes in non-high density lipoprotein(non-HDL),all patients were divided into the effective lipid-lowering group and the ineffective lipid-lowering group.The demographic information,plaques characteristics and the effect of standardized lipid-lowering therapy of all patients were compared.Results One(2.33%)plaque in the effective group showed reverse remodeling and four(18.18%)new plaques in the anterior circulation in the ineffective group.Patients in the effective group were significantly better than those in the ineffective group in terms of plaque thickness,load,remodeling index(RI),and the rate of increase in plaque thickness,load,stenosis,and RI,with statistically significant difference(P<0.05).There was no statistical significance in the rate of stenosis between the two groups.Conclusion Standardized lipid-lowering therapy has differences in the prognosis of acute stroke patients,and HRMR-VWI may be conducive to individualized assessment of the lipid-lowering effect.