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31.
浸润和转移是恶性肿瘤的重要特征,也给肿瘤的治疗带来困难,是预后不良的重要因素.转移抑制因子23(non-metastasis,NM23)基因是最早发现的抗肿瘤转移基因之一.现在已经发现NM23是一个基因家族,包括NM23-H1、NM23-H2等重要的基因家族成员.研究表明NM23基因表达与实体瘤转移抑制有关,在很多实体瘤中可以作为进展和预后的分子标记.随着对NM23基因调控肿瘤转移的分子机制的研究的进一步开展,已经发现了一些NM23肿瘤转移抑制通路上下游的相关调控分子,为进一步的信号通路研究创造了条件.本文概述了近年来对NM23基因转移抑制通路研究的新近展,提出了以后可能的研究方向和需要解决的关键问题. 相似文献
32.
Andrea M. Gross Megan Frone Karen W. Gripp Bruce D. Gelb Lisa Schoyer Lisa Schill Beth Stronach Leslie G. Biesecker Dominic Esposito Edjay Ralph Hernandez Eric Legius Mignon L. Loh Staci Martin Deborah K. Morrison Katherine A. Rauen Pamela L. Wolters Dina Zand Frank McCormick Sharon A. Savage Douglas R. Stewart Brigitte C. Widemann Marielle E. Yohe 《American journal of medical genetics. Part A》2020,182(4):866-876
RASopathies caused by germline pathogenic variants in genes that encode RAS pathway proteins. These disorders include neurofibromatosis type 1 (NF1), Noonan syndrome (NS), cardiofaciocutaneous syndrome (CFC), and Costello syndrome (CS), and others. RASopathies are characterized by heterogenous manifestations, including congenital heart disease, failure to thrive, and increased risk of cancers. Previous work led by the NCI Pediatric Oncology Branch has altered the natural course of one of the key manifestations of the RASopathy NF1. Through the conduct of a longitudinal cohort study and early phase clinical trials, the MEK inhibitor selumetinib was identified as the first active therapy for the NF1‐related peripheral nerve sheath tumors called plexiform neurofibromas (PNs). As a result, selumetinib was granted breakthrough therapy designation by the FDA for the treatment of PN. Other RASopathy manifestations may also benefit from RAS targeted therapies. The overall goal of Advancing RAS/RASopathy Therapies (ART), a new NCI initiative, is to develop effective therapies and prevention strategies for the clinical manifestations of the non‐NF1 RASopathies and for tumors characterized by somatic RAS mutations. This report reflects discussions from a February 2019 initiation meeting for this project, which had broad international collaboration from basic and clinical researchers and patient advocates. 相似文献
33.
The major phospholipids present in the phospholipid extract of Schistosoma mansoni were phosphatidylcholine (28%), phosphatidylethanolamine (25%), phosphatidylserine (15%) and phosphatidylglycerol (8%). The synthesis of phosphatidylcholine in S. mansoni adults occurred by the choline to phosphatidylcholine or Kennedy pathway. Incorporation of CDPcholine and choline into the phosphatidylcholine of worm slices appeared linear over time with no demonstrable sex differences in choline incorporation. A slight difference in the incorporation of CDPcholine by separate sexes was evident. Methylation of phosphatidylethanolamine to phosphatidylcholine could not be demonstrated. 相似文献
34.
L. S. Jen R. D. Lund J. Boles 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1978,33(3-4):405-414
Summary An aberrant crossed corticotectal pathway can be generated by removal of one visual cortex and the contralateral superior colliculus from newborn rats. This aberrant crossed corticotectal projection arises from the pyramidal neurons located in layer V of the visual cortex and terminates in a spatially orderly manner in the appropriate laminae of the cortically deafferented contralateral colliculus. Comparable results cannot be reproduced by unilateral collicular lesions alone. The significance of these findings and the possible mechanisms involved in the formation of the aberrant pathway are discussed and compared with the retinotectal system.The research was supported by USPHS Grant EY-00596 from the National Institutes of Health 相似文献
35.
目的:从基因水平研究肝移植急性排斥反应中T淋巴细胞信号传导途径。方法:利用4096条大鼠cDNA克隆的基因芯片对从急性排斥组Wistar→SD(n=5)和对照组SD→SD(n=5)两组肝移植大鼠T细胞中抽提、纯化mRNA,扩增、逆转录成cDNA,荧光标记后与芯片杂交,扫描后筛选出差异表达的基因。结果:在4096个基因中共发现差异表达基因190条,其中ll条与细胞信号传导有关的基因差异表达明显:MHC(3条)、CD3抗原(1条)相关基因;蛋白酶类:蛋白激酶C结合蛋白、蛋白酪氨酸磷酸酯酶D型受体、磷脂酰肌醇二磷酸酶基因各l条;涉及核酸信号传导、激活、转录、翻译的基因3条。结论:T细胞在肝移植术后排斥反应中信号传导机制涉及多个基因,基因芯片技术的大规模筛选为进一步研究T细胞在排斥反应中的信号传导途径提供了客观依据和目标。 相似文献
36.
目的 进一步研究NOD小鼠T细胞应答改变机理。方法 用抗TCR抗体、ConA激活NOD小鼠胸腺细胞,分析TCR介导的信号通路的水平。结果 与Balb/c小鼠胸腺细胞相比,抗TCR抗体诱导的增殖应答较弱,与年龄及NOD胸腺CD4^ CD8^-和CD4^-CD8^ SP细胞有关;rIL-2能部分恢复对TCR抗体应答的缺乏。NOD小鼠对PMA IONO和PMA anti—TCR-mAb应答正常,但对anti-TCRmAb IONO应答缺乏。结论 与年龄有关的NOD小鼠胸腺细胞对TCR抗体应答的缺乏与T细胞激活时上游PKC信号通路的缺乏有关。 相似文献
37.
Antibody content against rabbit red blood cells (anti-RaRBC) in murine sera of different strains (Swiss, CBA, C57BL/6, AKR, BALB/c) and activity of complement alternative pathway (AP) were investigated. In contrast to the CBA and C57BL/6, random-bred Swiss strain and inbred BALB/c and AKR strains are good producers of these natural antibodies. There is no correlation between AP activity and anti-RaRBC content. Isolated human anti-RaRBC antibodies, IgM and IgG classes, lead to the enhancement of APhu and APmo activity, contrary to the murine anti-RaRBC which belong solely to IgM class, and do not express this capability. 相似文献
38.
L. D. Luk'yanova G. N. Chernobaeva V. E. Romanova 《Bulletin of experimental biology and medicine》1989,107(4):482-484
Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. V. Val'dman.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 4, pp. 431–433, April, 1989. 相似文献
39.
浸润和转移是恶性肿瘤的重要特征,也给肿瘤的治疗带来困难,是预后不良的重要因素.转移抑制因子23(non-metastasis,NM23)基因是最早发现的抗肿瘤转移基因之一.现在已经发现NM23是一个基因家族,包括NM23-H1、NM23-H2等重要的基因家族成员.研究表明NM23基因表达与实体瘤转移抑制有关,在很多实体瘤中可以作为进展和预后的分子标记.随着对NM23基因调控肿瘤转移的分子机制的研究的进一步开展,已经发现了一些NM23肿瘤转移抑制通路上下游的相关调控分子,为进一步的信号通路研究创造了条件.本文概述了近年来对NM23基因转移抑制通路研究的新近展,提出了以后可能的研究方向和需要解决的关键问题. 相似文献
40.
A. Cevese R. Grasso R. Poltronieri F. Schena G. Vacca 《Pflügers Archiv : European journal of physiology》1993,424(5-6):488-493
Distension of the descending colon elicits reflex cardiovascular responses, including increases in heart rate and arterial blood pressure. To study the relative contribution of vasoconstriction in individual vascular beds to this reflex response, experiments were performed on seven dogs anaesthetised with chloralose and instrumented with electromagnetic flowmeters around the superior mesenteric, the left renal and the left external iliac arteries. The colorectal portion of the intestine was distended at constant pressure (36.6 mm Hg, 4.9 kPa mean; range 25–50 mm Hg, 3.3–6.7 kPa) with warm Ringer solution for periods of 2 min. After a set of control distensions, the experiments were performed whilst the reflex rise in arterial pressure was prevented by removal of blood from the arterial tree. In control distensions arterial pressure increased by 11.3±1.5 mm Hg, 1.51±0.12 kPa (mean±SEM). In distensions at constant arterial pressure, peripheral blood flows were altered to different extents in the three territories studied: vascular resistance increased by 30.8±5.6% (P<0.01) in the mesenteric, by 4.1±1.5% (P<0.03) in the renal, and by 15.2±6.8% (NS) in the external iliac bed. We conclude that colorectal distension may reflect activation of a function-specific pathway of the sympathetic nervous system, which leads to much greater vasoconstriction in the splanchnic circulation than in renal or musculocutaneous circulations. 相似文献