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排序方式: 共有912条查询结果,搜索用时 31 毫秒
181.
Buckley AR Krumenacker JS Buckley DJ Leff MA Magnuson NS Reed JC Miyashita T de Jong G Gout PW 《Apoptosis : an international journal on programmed cell death》1997,2(6):518-528
The parental rat Nb2 lymphoma is a prolactin (PRL)-dependent T cell line. Exposure of a PRL-independent subline, Nb2-SFJCD1,
to sodium butyrate (NaBT) causes transient reversal of their growth factor-independent proliferation in association with constitutive
expression of protooncogenes pim-1and c-myc. In the present study, we investigated the effect of NaBT treatment on the sensitivity
of Nb2-SFJCD1 cells to dexamethasone (DEX)-induced apoptosis. Pretreatment with NaBT (2 mM, 72 h) partially reversed resistance
to apoptosis in Nb2-SFJCD1 cells exposed to DEX (100 nM) for 12 h, assessed by flow cytometric analyses of DNA fragmentation.
However, the cytolytic effect of DEX was abrogated by PRL i n a time- and concentration-dependent manner. Eval uati on of
apoptosis-associated gene expression in NaBT-pre-treated cultures incubated with DEX or DEX+PRL indicated that the apoptosis
resistance did not stem from altered bcl-2 or bax expression. However, there was a strong correlation between the resistance
to DEX-activated apoptosis and their enhanced expression of pim-1 mRNA and protein. The results show that it is possible to
reverse DEX-induced apoptosis of Nb2 pre-T cells and suggest the pim-1 gene product has an important role as a suppressor
of this process, perhaps functioning as a mediator of PRL action.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
182.
Primary malignant lymphoma of the uterine cervix: report of a case with cytologic and immunohistochemical diagnosis 总被引:3,自引:0,他引:3
A non‐Hodgkin's lymphoma initially diagnosed on the cervical smear in a 69‐year‐old asymptomatic female is described. The cytologic findings strongly suggested the presence of a malignant lymphoid neoplasm: neoplastic cells were round, loosely arranged, with scanty cytoplasm and cleaved nuclei. Histological evaluation of the cervical biopsy revealed a diffuse lymphoid proliferation of mononucleated cleaved cells beneath an ulcerated epithelium. Immunohistochemically, the tumour cells were positive for B cell markers. Reports on cytologic features of primary malignant lymphoma of the cervix are not frequent in the literature. We emphasize the importance of their recognition and the differential diagnosis of cervical lymphoma from other neoplastic and non‐neoplastic lesions. 相似文献
183.
184.
Pradeep Kumar Kopparapu Sujata Bhoi Larry Mansouri Laleh S. Arabanian Karla Plevova Sarka Pospisilova 《Epigenetics》2016,11(5):335-343
Downregulation of miR26A1 has been reported in various B-cell malignancies; however, the mechanism behind its deregulation remains largely unknown. We investigated miR26A1 methylation and expression levels in a well-characterized series of chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL). From 450K methylation arrays, we first observed miR26A1 (cg26054057) as uniformly hypermethylated in MCL (n = 24) (all >75%), while CLL (n = 18) showed differential methylation between prognostic subgroups. Extended analysis using pyrosequencing confirmed our findings and real-time quantitative PCR verified low miR26A1 expression in both CLL (n = 70) and MCL (n = 38) compared to normal B-cells. Notably, the level of miR26A1 methylation predicted outcome in CLL, with higher levels seen in poor-prognostic, IGHV-unmutated CLL. Since EZH2 was recently reported as a target for miR26A1, we analyzed the expression levels of both miR26A1 and EZH2 in primary CLL samples and observed an inverse correlation. By overexpression of miR26A1 in CLL and MCL cell lines, reduced EZH2 protein levels were observed using both Western blot and flow cytometry. In contrast, methyl-inhibitor treatment led to upregulated miR26A1 expression with a parallel decrease of EZH2 expression. Finally, increased levels of apoptosis were observed in miR26A1-overexpressing cell lines, further underscoring the functional relevance of miR26A1. In summary, we propose that epigenetic silencing of miR26A1 is required for the maintenance of increased levels of EZH2, which in turn translate into a worse outcome, as shown in CLL, highlighting miR26A1 as a tumor suppressor miRNA. 相似文献
185.
目的:比较环磷酰胺-西艾克-吡柔比星-泼尼松(Cyclophosphamidum-Vindesine-Tetrahydropyranyl-Prednisone,CVTP)联合化疗方案对初治和复治、难治恶性淋巴瘤的临床疗效。方法:按照化疗史将102例恶性淋巴瘤患者分为初治组59例和复治难治组43例,两组患者均给予CVTP联合化疗方案治疗,比较两组化疗效果、外周血淋巴细胞亚群、毒副反应差别。结果:初治组患者部分缓解(partial remission,PR)率和总有效率(overall response rate,ORR)均显著高于对复治难治组,差异具有统计学意义(P0.05);初治组患者治疗后CD3~+、CD4~+、CD4~+/CD8~++、NK细胞含量均显著高于复治难治组,CD8~+水平显著低于复治难治组,差异具有统计学意义(P0.05);初治组患者化疗期间白细胞下降、血红蛋白下降、血小板减少、恶心呕吐发生率均显著低于复治难治组,差异具有统计学意义(P0.05)。结论:CVTP联合化疗方案治疗初治恶性淋巴瘤近期疗效优于复治难治患者。 相似文献
186.
目的:探讨GDP与CHOP方案治疗非特异性外周T细胞淋巴瘤的临床疗效,为临床治疗提供参考。方法:选择2013年1月到2016年1月我院收治的非特异性外周T细胞淋巴瘤患者80例,随机分为GDP组(n=40)和CHOP组(n=40)。GDP组患者给予GDP治疗方案(顺铂+吉西他滨+强的松),CHOP组患者给予CHOP治疗方案(多柔比星+环磷酰胺+长春新碱+强的松),两组患者均治疗6个疗程。比较两组患者临床疗效和不良反应发生情况。结果:GDP组患者近期疗效总有效率为75.00%,明显高于CHOP组的45.00%,差异具有统计学意义(P0.05)。GDP组患者的无进展生存期(PFS)、总生存期(OS)分别为(9.69±1.50)月和(16.72±3.06)月,明显大于CHOP组的(5.16±1.38)月和(10.98±3.37)月,差异具有统计学意义(P0.05)。GDP组患者恶心呕吐的发生率为72.50%,明显低于CHOP组的97.50%,差异具有统计学意义(P0.05)。结论:GDP方案治疗非特异性外周T细胞淋巴瘤的临床疗效明显优于CHOP方案,且不良反应发生率低,值得在临床上推广应用。 相似文献
187.
P G Plagemann 《Journal of cellular biochemistry》1991,46(1):54-59
S49 murine lymphoma cells were examined for expression of various nucleoside transport systems using a non-metabolized nucleoside, formycin B, as substrate. Nitrobenzylthioinosine (NBTI)-sensitive, facilitated transport was the primary nucleoside transport system of the cells. The cells also expressed very low levels of NBTI-resistant, facilitated nucleoside transport as well as of Na(+)-dependent, concentrative formycin B transport. Concentrative transport was specific for uridine and purine nucleosides, just as the concentrative nucleoside transporters of other mouse and rat cells. A nucleoside transport mutant of S49 cells, AE-1, lacked both the NBTI-sensitive, facilitated and Na(+)-dependent, concentrative formycin B transport activity, but Na(+)-dependent, concentrative transport of alpha-aminoisobutyrate was not affected. 相似文献
188.
Johannes Müthing Jasna Peter-Katalinić Franz-Georg Hanisch Ulrich Neumann 《Glycoconjugate journal》1991,8(5):414-423
YAC-1 cells were propagated in bioreactors in 11 and 7.51 volumes. The cells were metabolically labelled withd-[1-14C]galactose andd-[1-14C]glucosamine. The ganglioside fraction, purified by DEAE-Sepharose and silica gel column chromatography, showed on thin layer chromatography four major bands with mobilities between GM1 and GD1a. Gangliosides, obtained by further purification steps including high performance liquid chromatography on silica gel 60 columns with a gradient system of isopropanol:hexane:water, and preparative high performance TLC were characterized by (1) immunostaining of corresponding asialogangliosides obtained by mild acid hydrolysis and neuraminidase treatment and (2) fast atom bombardment mass spectrometry of native and permethylated samples and methylation analysis of GM1b ganglioside. As well as small amounts of GM2 and GM1, the major gangliosides found in the complex mixture were GM1b and GalNAc-GM1b. The structural heterogeneity of these gangliosides was cased by (a) substitution of the ceramide moiety by fatty acids of different chain length and degree of unsaturation (C16:0, C24:0, C24:1) and (b) N-substitution of the sialic acid moieties with either acetyl or glycolyl groups. Disialogangliosides were detected only in low amounts and will be the subject of further investigation. A polyclonal chicken antiserum was raised against IVNeuAc-GgOse5Cer. The antiserum was highly specific for gangliosides (IVNeuAc and IVNeuGc) and asialogangliosides with a GgOse5Cer backbone. No cross-reaction with GM1b or GgOse4Cer was observed.
Abbreviations: FAB-MS, fast atom bombardment mass spectrometry; GSL(s), glycosphingolipid(s); HPLC, high performance liquid chromatography, HPTLC, high performance thin layer chromatography; NK, natural killer; SIM, selective ion monitoring; TIC, total ion current. NeuAc,N-acetylneuraminic acid; NeuGc,N-glycolylneuraminic acid. The designation of the following glycosphingolipids follows the IUB-IUPAC recommendations. GgOse3Cer or gangliotriaosylceramide or asialo GM2, GalNAc1-4Gal1-4GlcCer; GgOse4Cer or gangliotetraosylceramide or asialo GM1, Gal1-3GalNAc1-4Gal1-4GlcCer; GgOse5Cer organgliopentaosylceramide, GalNAc1-4Gal1-3GalNAc1-4Gal1-4GlcCer; II3NeuAc-GgOse4Cer or GM1; IV3NeuAcGgOse4Cer or GM1b; IV3NeuAc-GgOse5Cer or GalNAc-GM1b; IV3NeuAc, II3NeuAc-GgOse4Cer or GD1a; II3(NeuAc)2-GgOse4Cer or GD1b; IV3(NeuAc)2-GgOse4Cer or GD1c; IV3NeuAc,III6NeuAc-GgOse4Cer or GD1a; IV3NeuAc,II3(NeuAc)2-GgOse4Cer or GT1b;Vibrio cholerae and Arthrobacter ureafaciens neuraminidase (EC 3.2.1.18). 相似文献
189.
Summary We have previously shown that the interaction of thymocytes with thymic accessory cells (macrophages and/or interdigitating cells) is one of the factors required for thymocyte activation. Precursors of both thymic accessory cell and thymocytes are included in the CD4- CD8- Mac-1- Ia- subpopulation, and their respective maturation and/or activation may be modulated by granulocyte-macrophage colony-stimulating factor, interleukin 1 and interleukin 2. When CD4- CD8- thymic cells are activated with granulocyte-macrophage colony-stimulating factor plus interleukin 2, both macrophages and interdigitating-like cells are present, as shown by electron microscopy. When activated with interleukin 1 plus interleukin 2, the interdigitating-like cells is the only accessory cell present. In both culture conditions, large clusters are formed between interdigitating cells and lymphoid cells. These results have led us to propose two-step signals for thymocyte proliferation: first, the maturation of macrophages under granulocyte-macrophage colony-stimulating factor control and the production of interleukin 1, and secondly, the maturation of interdigitating cells under interleukin 1 control, their clustering with thymocytes which are then activated.Abbreviations CFU-S
colony-forming units in the spleen
- CSF
colony-stimulating factor
- DC
dendritic cells
- DN
double negative cells (CD4- CD8-)
- EC
epithelial cells
- GM-CFC
granulocyte/macrophage colony-forming cells
- GM-CSF
granulocytemacrophage CSF
- IDC
interdigitating cell
- IL-1
interleukin 1
- IL-2
interleukin 2
- MØ
macrophage
- P-TR
phagocytic cell of the thymic reticulum 相似文献
190.
Summary Immunotherapy of a murine B-cell lymphoma by antibodies to idiotypic determinants of its IgM, resulted in surviving tumour-free mice. Several of these mice, however, did develop tumours a long time after the initial inoculation of the tumour cells, or upon rechallange of the survivors with B-lymphoma cells. The presence of tumour cells during this long latent period may have been due to the development in the host of an anti-idiotype immune response. These late-developing tumours were detected by a radioimmunoassay and characterized by immunofluorescent staining and sodium dodecyl sulphate/polyacrylamide gel electrophoresis. Cells of some late-developing tumours lost the idiotype recognized by the antibodies used for the immunotherapy. Several of these tumours expressed IgM on the cell surface, while others did not, because of the absence of light chains. They were identical in the structure of their rearranged µ chain genes proving their derivation from the original inoculation. Cell lines obtained from the late-developing tumours differed in their tumorigenicity. The appearance of idiotype-negative tumour cells as a result of anti-idiotype immunotherapy has a great impact in our efforts to cure lymphoma by this modality. 相似文献