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41.
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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Kyler Mulhauser Jeremiah Weinstock Phillip Ruppert Jeffrey Benware 《Substance use & misuse》2018,53(6):881-890
Background: Neuropsychological deficits are common in individuals with alcohol use disorder (AUD) and impact daily functioning and AUD treatment outcomes. Longitudinal studies demonstrate that extended abstinence improves neuropsychological functioning. The effects of short-term abstinence are less clear. Objectives: This study examined changes in neuropsychological functioning after acute detoxification over a 10-day period at the beginning of residential AUD treatment. Notably, this study evaluated cognitive functioning according to diagnostic classifications for neurocognitive disorder according to DSM-5. Methods: Using a within-subjects design, neuropsychological functioning of participants (N = 28) undergoing a 14-day residential AUD treatment program was assessed at two time points over 10 days (i.e., treatment entry, prior to treatment discharge). Tests of immediate memory, visuospatial abilities, attention, language abilities, delayed memory, and executive functioning were administered. Results: After completing acute detoxification, almost all participants (93%) were clinically impaired in at least one of the five cognitive domains at residential treatment entry, with one third of the sample impaired on ≥3 domains. Ten days later, 71% remained clinically impaired in at least one of five cognitive domains, with 29% of the sample impaired on ≥3 domains. Significant improvement over the 10-day period was observed for immediate memory, visuospatial abilities, and overall cognitive functioning. Clinical significance of these changes is also reported. Conclusions/Importance: The results from this study help to characterize cognitive functioning in terms of neurocognitive impairment. A brief period of abstinence begins to ameliorate neuropsychological deficits, but many individuals remain cognitively impaired throughout treatment. Implications for treatment are discussed. 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