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991.
992.
目的探讨维纳托克(Venetoclax)在HepG2、Hep3B 2个肝癌细胞株的抗癌活性。方法对人肝癌细胞株HepG2、Hep3B细胞株进行体外培养,采用不同浓度的Venetoclax(0、3、10、30μmol/L)处理肝癌细胞,以细胞计数试剂盒(CCK-8)检测细胞活性,0,3,10和30μmol/L Venetoclax作用细胞48 h,锥虫蓝拒染法检测细胞的死亡,0,5μmol/L Venetoclax,作用24 h,流式细胞学检测细胞凋亡率,蛋白质印迹法(Western blot)检测Venetoclax诱导半胱氨酰天冬氨酸特异性蛋白酶(Caspase)-3活化,聚腺苷二磷酸核糖聚合酶(PARP)裂解。组间比较采用t检验。结果Venetoclax对HepG2、Hep3B细胞株均有较强活性抑制作用。不同浓度的Venetoclax处理肝癌细胞48、72 h,Venetoclax在HepG2细胞株中取得的半数细胞活性抑制率(IC50)值分别为46.5μmol/L和14.2μmol/L;在Hep3B细胞的IC50值分别为24.6μmol/L和11.2μmol/L。处理24 h,30.0μmol/L的Venetoclax在HepG2和Hep3B细胞株中诱导57%[对照组、实验组凋亡率分别为(4.00±1.00)%、(56.67±8.51)%,t=-10.650,P<0.01]和54%[对照组、实验组凋亡率分别为(5.67±1.53)%、(54.33±9.87)%,t=-8.440,P<0.01]的肝癌细胞发生凋亡,并能诱导肝癌细胞的Caspase-3活化,PARP裂解,差异均有统计学意义。用0、3、10和30μmol/L的Venetoclax处理48 h,在HepG2细胞株中可诱导3%(3.26±1.71)%,12%[(12.36±1.99)%,(t=-12.36,P<0.05)],32%[(32.38±4.57)%,(t=-10.350,P<0.01)]和67%[(66.71±6.29)%,(t=-16.86,P<0.01)]的细胞死亡,差异均有统计学意义;在Hep3B细胞株诱导2%(1.91±0.68)%,16%[(15.72±3.40)%,(t=-6.890,P<0.05)],42%[(42.39±6.86)%,(t=-10.180,P<0.01)]和73%[(73.32±2.69)%,t=-44.490,P<0.01]的细胞死亡,差异均有统计学意义。应用半胱氨酸蛋白酶(Caspase)抑制剂预处理,Venetoclax对HepG2和Hep3B细胞的死亡率分别从56%(56.71±6.29)%降低至11%(10.70±1.43)%,(t=12.350,P<0.01)和68%(68.05±10.16)%至12%(12.7±6.12)%,(t=8.080,P<0.01),差异有统计学意义。结论Venetoclax能够通过诱导Caspase的活化,诱导肝癌细胞发生凋亡,并对肝癌细胞进行杀伤。 相似文献
993.
C.A.P.F. Alves U. Lbel J.S. Martin-Saavedra S. Toescu M.H. Tsunemi S.R. Teixeira K. Mankad D. Hargrave T.S. Jacques C. da Costa Leite F.G. Gonalves A. Vossough F. D'Arco 《AJNR. American journal of neuroradiology》2021,42(5):961
BACKGROUND AND PURPOSE:Primary posterior fossa tumors comprise a large group of neoplasias with variable aggressiveness and short and long-term outcomes. This study aimed to validate the clinical usefulness of a radiologic decision flow chart based on previously published neuroradiologic knowledge for the diagnosis of posterior fossa tumors in children.MATERIALS AND METHODS:A retrospective study was conducted (from January 2013 to October 2019) at 2 pediatric referral centers, Children''s Hospital of Philadelphia, United States, and Great Ormond Street Hospital, United Kingdom. Inclusion criteria were younger than 18 years of age and histologically and molecularly confirmed posterior fossa tumors. Subjects with no available preoperative MR imaging and tumors located primarily in the brain stem were excluded. Imaging characteristics of the tumors were evaluated following a predesigned, step-by-step flow chart. Agreement between readers was tested with the Cohen κ, and each diagnosis was analyzed for accuracy.RESULTS:A total of 148 cases were included, with a median age of 3.4 years (interquartile range, 2.1–6.1 years), and a male/female ratio of 1.24. The predesigned flow chart facilitated identification of pilocytic astrocytoma, ependymoma, and medulloblastoma sonic hedgehog tumors with high sensitivity and specificity. On the basis of the results, the flow chart was adjusted so that it would also be able to better discriminate atypical teratoid/rhabdoid tumors and medulloblastoma groups 3 or 4 (sensitivity = 75%–79%; specificity = 92%–99%). Moreover, our adjusted flow chart was useful in ruling out ependymoma, pilocytic astrocytomas, and medulloblastoma sonic hedgehog tumors.CONCLUSIONS:The modified flow chart offers a structured tool to aid in the adjunct diagnosis of pediatric posterior fossa tumors. Our results also establish a useful starting point for prospective clinical studies and for the development of automated algorithms, which may provide precise and adequate diagnostic tools for these tumors in clinical practice.In the past 10 years, there has been an exponential increase in knowledge of the molecular characteristics of pediatric brain tumors, which was only partially incorporated in the 2016 World Health Organization Classification of Tumors of the Central Nervous System.1 The main update in the 2016 Classification was the introduction of the molecular profile of a tumor as an important factor for predicting different biologic behaviors of entities which, on histology, look very similar or even indistinguishable.2 A typical example is the 4 main groups of medulloblastoma: wingless (WNT), sonic hedgehog (SHH) with or without the p53 mutation, group 3, and group 4. Although they may appear similar on microscopy, these categories have distinct molecular profiles, epidemiology, prognosis, and embryologic origin.3Subsequent to the publication of the 2016 World Health Organization Classification, further studies have identified even more molecular subgroups of medulloblastoma with possible prognostic implications4 and also at least 3 new molecular subgroups of atypical teratoid/rhabdoid tumor (AT/RT)5 and several subgroups of ependymoma.6 MR imaging shows promise as a technique for differentiating histologic tumors and their molecular subgroups. This capability relies on not only various imaging characteristics but also the location and spatial extension of the tumor, evident on MR imaging, which can be traced to the embryologic origin of the neoplastic cells.5,7-10One approach to the challenge of identifying imaging characteristics of different tumors in children is to use artificial intelligence. Yet despite this exciting innovation, correctly identifying the location of the mass and its possible use as an element for differential diagnosis still requires the expertise of an experienced radiologist. Previously, D''Arco et al11 proposed a flow chart (Fig 1) for the differential diagnosis of posterior fossa tumors in children based on epidemiologic, imaging signal, and location characteristics of the neoplasm. The aims of the current study were the following: 1) to validate, in a retrospective, large cohort of posterior fossa tumors from 2 separate pediatric tertiary centers, the diagnostic accuracy of that flow chart, which visually represents the neuroadiologist''s mental process in making a diagnosis of posterior fossa tumors in children, 2) to describe particular types of posterior fossa lesions that are not correctly diagnosed by the initial flow chart, and 3) to provide an improved, clinically accessible flow chart based on the results.Open in a separate windowFIG 1.Predesigned radiologic flow chart created according to the literature before diagnostic accuracy analysis. The asterisk indicates brain stem tumors excluded from the analysis. Double asterisks indicate relative to gray matter. Modified with permission from D''Arco et al.11 相似文献
994.
目的 研究酸枣仁汤对老年慢性睡眠剥夺模型大鼠核受体PPARγ及其共激活因子PGC-1α表达的影响。方法 将50只雄性Wistar大鼠随机分为环境对照组、模型组、阳性对照组、酸枣仁汤低、高剂量组,除环境对照组外,其余各组均皮下注射D-半乳糖,于末次给药后进行多平台水环境睡眠剥夺,造模结束后各组开始灌胃给药,连续给药7天。采用自主活动仪检测大鼠光照环境活动时间、黑暗环境活动时间、总活动时间,采用比色法检测大鼠下丘脑ATP含量的变化,采用Real Time-PCR、Western-blot和免疫组化分别检测大鼠下丘脑核受体PPARγ及其共激活因子PGC-1α mRNA和蛋白表达水平。结果 与环境对照组比较,模型组大鼠光照环境活动时间、黑暗环境活动时间、总活动时间均显著增加(P < 0.01);与模型组比较,阳性对照组、酸枣仁汤高剂量组光照环境活动时间、黑暗环境活动时间、总活动时间均显著减少(P < 0.05,P < 0.01);与环境对照组比较,模型组下丘脑ATP含量显著降低(P < 0.01);与模型组比较,阳性对照组、酸枣仁汤高剂量组下丘脑ATP含量显著升高(P < 0.05);与环境对照组比较,模型组核受体PPARγ及其共激活因子PGC-1α mRNA和蛋白表达水平显著降低(P < 0.01,P < 0.05);与模型组比较,阳性对照组、酸枣仁汤高剂量组核受体PPARγ及其共激活因子PGC-1α mRNA和蛋白表达水平显著升高(P < 0.01,P < 0.05)。结论 酸枣仁汤有可能基于PPARγ及其共激活因子PGC-1α同时调控昼夜节律与能量代谢。 相似文献
995.
996.
L.S. Becker S.K. Maschke C.L.A. Dewald T.C. Meine H.B.M. Winther M.M. Kirstein R. Kloeckner B.C. Meyer F. Wacker J.B. Hinrichs 《Clinical radiology》2021,76(2):160.e27-160.e33
997.
Capriola-Hall Nicole N. McFayden Tyler Ollendick Thomas H. White Susan W. 《Journal of autism and developmental disorders》2021,51(5):1540-1549
Journal of Autism and Developmental Disorders - Social anxiety disorder (SAD) is commonly comorbid with autism spectrum disorder (ASD). Here, in a sample of 86 children and adolescents... 相似文献
998.
999.
A.M.E. Jansen J.D. Sriram D. Pluim R.J.H. Maas H. van Groningen B. Piet R. ter Heine 《Clinical lung cancer》2021,22(2):e220-e223
1000.
随着近年来交通和工业的快速发展,脊髓损伤患者也不断增加,现已成为严重的社会负担,但却一直没有理想的治疗方案。继发性损伤是脊髓损伤后分子和细胞发生的一系列复杂的级联反应。它是SCI的重要组成部分,阐明继发性损伤的机制,针对不同的机制采取不同的干预措施是主要的治疗策略。而星形胶质细胞作为中枢神经系统中数量最多的细胞,在脊髓损伤后发挥了重要作用,受到研究人员的广泛关注,许多研究证明针刺可通过调节星形胶质细胞而发挥治疗作用,故本文综述了星形胶质细胞在脊髓损伤后的作用,以及针刺对其的干预影响,并提出日后研究的展望。 相似文献