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目的:观察p53抑制剂pifithrin-α对肝原代细胞增殖及增殖相关蛋白表达的影响。方法:肝原代细胞分别经0、10、20和30μmol/L的pifithrin-α处理1h后,再用10nmol/LEGF诱导30、36和48h,用放射性计数法测定细胞增殖水平。另取肝原代细胞,分3组,对照组常规培养,EGF组用10nmol/L的EGF诱导,EGF+pifithrin-α组用30μmol/Lpifithrin-α和10nmol/LEGF诱导,EGF诱导24、30h后,Westernblot法检测细胞中P53、P21、CyclinD、CyclinE、pErk蛋白的表达水平。结果:pifithrin-α作用后,EGF诱导的细胞增殖水平均降低,且pifithrin-α浓度越大,增殖水平越低(F剂量=54.690,F时间=214.370,F交互=50.450,P<0.001)。与对照组比较,EGF组细胞P53、Cyc-linE蛋白表达水平未发生变化,但P21、CyclinD及pErk表达水平升高(P<0.05),EGF+pifithrin-α组细胞P21、CyclinD及pErk蛋白表达水平较EGF组降低(P<0.05)。结论:P53蛋白可能通过激活MAPK信号通路、上调Cy-clinD表达,从而发挥促进肝原代细胞增殖的作用。 相似文献
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Leila H. Shayegan BA MD Candidate Maria C. Garzon MD Kimberly D. Morel MD Rachel Borlack MD Patricia M. Vuguin MD Kara G. Margolis MD Yesim Y. Demirdag MD Elaine M. Pereira MD Christine T. Lauren MD MHA 《Pediatric dermatology》2020,37(4):695-697
We report a case of a newly recognized primary immunodeficiency due to biallelic mutations in CARMIL2 manifesting as an actinic prurigo-like photodermatitis, allergic diathesis and recurrent infections in a child. We present this case to highlight a rare phenotype seen in this T-cell immunodeficiency and provide an overview of other dermatologic manifestations among published reports of this condition. 相似文献
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Cloning, expression, and properties of the microtubule-stabilizing protein STOP. 总被引:3,自引:0,他引:3
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C Bosc J D Cronk F Pirollet D M Watterson J Haiech D Job R L Margolis 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(5):2125-2130
Nerve cells contain abundant subpopulations of cold-stable microtubules. We have previously isolated a calmodulin-regulated brain protein, STOP (stable tubule-only polypeptide), which reconstitutes microtubule cold stability when added to cold-labile microtubules in vitro. We have now cloned cDNA encoding STOP. We find that STOP is a 100.5-kDa protein with no homology to known proteins. The primary structure of STOP includes two distinct domains of repeated motifs. The central region of STOP contains 5 tandem repeats of 46 amino acids, 4 with 98% homology to the consensus sequence. The STOP C terminus contains 28 imperfect repeats of an 11-amino acid motif. STOP also contains a putative SH3-binding motif close to its N terminus. In vitro translated STOP binds to both microtubules and Ca2+-calmodulin. When STOP cDNA is expressed in cells that lack cold-stable microtubules, STOP associates with microtubules at 37 degrees C, and stabilizes microtubule networks, inducing cold stability, nocodazole resistance, and tubulin detyrosination on microtubules in transfected cells. We conclude that STOP must play an important role in the generation of microtubule cold stability and in the control of microtubule dynamics in brain. 相似文献
58.
Impact of hepatitis B virus infection on women and children. 总被引:1,自引:0,他引:1
HBV infection acquired during infancy and early childhood has a high likelihood of progressing to chronic infection, which can lead to chronic hepatitis, cirrhosis, and primary hepatocellular carcinoma. In areas of the world where HBV infection occurs predominantly in infants and young children, routine infant immunization with hepatitis B vaccine is the most appropriate vaccination strategy. In the United States, the majority of HBV infections occur in adults with behaviors or occupations that put them at risk for HBV infection. Nevertheless, infection acquired during infancy and early childhood contributes significantly to the burden of chronic liver disease in the United States. Until recently, the vaccination strategy in the United States has included HBsAg screening of pregnant women and vaccination of infants born to infected women and vaccination of people in groups at high risk for HBV infection. Because of the difficulties in accessing and vaccinating persons from high-risk groups and the recent findings that HBV infection occurs more commonly among children in some groups in the United States than previously appreciated, the Immunization Practices Advisory Committee of the US Public Health Service and the American Academy of Pediatrics in 1991 endorsed a strategy of universal immunization of infants for hepatitis B. This strategy has the advantages of accessing infants in the United States through preexisting vaccine delivery systems and vaccinating individuals prior to their engaging in high-risk behavior. Continued screening of pregnant women for HBsAg is necessary to prevent perinatal HBV transmission and to identify for vaccination those household and sexual contacts of HBV carriers, a group that is also at high risk of HBV infection. 相似文献
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Increased circulating CSF-1 (M-CSF) in myeloproliferative disease: association with myeloid metaplasia and peripheral bone marrow extension 总被引:3,自引:1,他引:3
Myeloproliferative disease (MPD) is heterogeneous in phenotypic expression and may display features consistent with expansion and activation of the monocyte/macrophage population during its course. The role of colony-stimulating factor-1 (CSF-1) in the pathophysiology of MPD was investigated by measuring circulating CSF-1 levels and examining their relationship to disease phenotype. Serum CSF-1 concentrations, measured by radioimmunoassay, were elevated in all MPD phenotypes. CSF-1 levels differed significantly between groups of patients with essential thrombocythemia, polycythemia vera, and postpolycythemic or agnogenic myeloid metaplasia (in ascending order). CSF-1 serum levels were positively correlated with spleen size and the degree of peripheral bone marrow extension, determined by scintigraphy using a macrophage-seeking isotope. There was no correlation between CSF-1 concentration and circulating levels of erythrocytes, neutrophils or platelets, or the presence of bone marrow fibrosis. Elevated serum CSF-1 levels appear to be associated with an expanded monocyte/macrophage population in MPD. In view of the known cooperativity between CSF-1 and other growth factors in regulating hematopoiesis, the finding of increased serum CSF-1 concentrations and its association with myeloid metaplasia and bone marrow extension may indicate a pathophysiologic role for CSF-1 in determining the phenotypic expression of MPD. 相似文献
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Asvadi Nazanin Hajarol Afshari Mirak Sohrab Mohammadian Bajgiran Amirhossein Khoshnoodi Pooria Wibulpolprasert Pornphan Margolis Daniel Sisk Anthony Reiter Robert E. Raman Steven S. 《Abdominal imaging》2018,43(11):3117-3124
Abdominal Radiology - To evaluate 3T mpMRI characteristics of transition zone and peripheral zone index prostate cancer lesions stratified by Gleason Score and PI-RADSv2 with whole mount... 相似文献