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991.
Detection of multiple gene amplifications in glioblastoma multiforme using array-based comparative genomic hybridization 总被引:15,自引:0,他引:15
Hui AB Lo KW Yin XL Poon WS Ng HK 《Laboratory investigation; a journal of technical methods and pathology》2001,81(5):717-723
We have used a new method of genomic microarray to investigate amplification of oncogenes throughout the genome of glioblastoma multiforme (GBM). Array-based comparative genomic hybridization (array CGH) allows for simultaneous examination of 58 oncogenes/amplicons that are commonly amplified in various human cancers. Amplification of multiple oncogenes in human cancers can be rapidly determined in a single experiment. Tumor DNA and normal control DNA were labeled by nick translation with green- and red-tagged nucleotides, respectively. Instead of hybridizing to normal metaphase chromosomes in conventional comparative genomic hybridization (CGH), the probes of the mixed fluorescent labeled DNA were applied to genomic array templates comprised of P1, PAC, and BAC clones of 58 target oncogenes. The baseline for measuring deviations was established by performing a series of independent array CGH using test and reference DNA made from normal individuals. In the present study, we examined fourteen GBMs (seven cell lines and seven tumours) with CGH and array CGH to reveal the particular oncogenes associated with this cancer. High-level amplifications were identified on the oncogenes/amplicons CDK4, GLI, MYCN, MYC, MDM2, and PDGFRA. The highest frequencies of gains were detected on PIK3CA (64.3%), EGFR (57.1%), CSE1L (57.1%), NRAS (50%), MYCN (42.9%), FGR (35.7%), ESR (35.7%), PGY1 (35.7%), and D17S167 (35.7%). These genes are suggested to be involved in the GBM tumorigenesis. 相似文献
992.
Autoimmunity and glomerulonephritis in mice with targeted deletion of the serum amyloid P component gene: SAP deficiency or strain combination? 下载免费PDF全文
Gillmore JD Hutchinson WL Herbert J Bybee A Mitchell DA Hasserjian RP Yamamura K Suzuki M Sabin CA Pepys MB 《Immunology》2004,112(2):255-264
Human serum amyloid P component (SAP) binds avidly to DNA, chromatin and apoptotic cells in vitro and in vivo. 129/Sv x C57BL/6 mice with targeted deletion of the SAP gene spontaneously develop antinuclear autoantibodies and immune complex glomerulonephritis. SAP-deficient animals, created by backcrossing the 129/Sv SAP gene deletion into pure line C57BL/6 mice and studied here for the first time, also spontaneously developed broad spectrum antinuclear autoimmunity and proliferative immune complex glomerulonephritis but without proteinuria, renal failure, or increased morbidity or mortality. Mice hemizygous for the SAP gene deletion had an intermediate autoimmune phenotype. Injected apoptotic cells and isolated chromatin were more immunogenic in SAP(-/-) mice than in wild-type mice. In contrast, SAP-deficient pure line 129/Sv mice did not produce significant autoantibodies either spontaneously or when immunized with extrinsic chromatin or apoptotic cells, indicating that loss of tolerance is markedly strain dependent. However, SAP deficiency in C57BL/6 mice only marginally affected plasma clearance of exogenous chromatin and had no effect on distribution of exogenous nucleosomes between the liver and kidneys, which were the only tissue sites of catabolism. Furthermore, transgenic expression of human SAP in the C57BL/6 SAP knockout mice did not abrogate the autoimmune phenotype. This may reflect the different binding affinities of mouse and human SAP for nuclear autoantigens and/or the heterologous nature of transgenic human SAP in the mouse. Alternatively, the autoimmunity may be independent of SAP deficiency and caused by expression of 129/Sv chromosome 1 genes in the C57BL/6 background. 相似文献
993.
Marsh DR Carson JA Stewart LN Booth FW 《Journal of muscle research and cell motility》1998,19(8):897-907
Little is known conerning promoter regulation of genes in regenerating skeletal muscles. In young rats, recovery of muscle mass and protein content is complete within 21 days. During the initial 5–10 days of regeneration, mRNA abundance for IGF-I, myogenin and MyoD have been shown to be dramatically increased. The skeletal -actin promoter contains E box and serum response element (SRE) regulatory regions which are directly or indirectly activated by myogenin (or MyoD) and IGF-I proteins, respectively. We hypothesized that the skeletal -actin promoter activity would increase during muscle regeneration, and that this induction would occur before muscle protein content returned to normal. Total protein content and the percentage content of skeletal -actin protein was diminished at 4 and 8 days and re-accumulation had largely occurred by 16 days post-bupivacaine injection. Skeletal - actin mRNA per whole muscle was decreased at day 8, and thereafter returned to control values. During regeneration at day 8, luciferase activity (a reporter of promoter activity) directed by –424 skeletal -actin and –99 skeletal -actin promoter constructs was increased by 700% and 250% respectively; however, at day 16, skeletal -actin promoter activities were similar to control values. Thus, initial activation of the skeletal - actin promoter is associated with regeneration of skeletal muscle, despite not being sustained during the later stages of regrowth. The proximal SRE of the skeletal -actin promoter was not sufficient to confer a regeneration-induced promoter activation, despite increased serum response factor protein binding to this regulatory element in electrophoretic mobility shift assays. Skeletal -actin promoter induction during regeneration is due to a combination of regulatory elements, at least including the SRE and E box. © Kluwer Academic Publishers. 相似文献
994.
Cellular localization of simian immunodeficiency virus in lymphoid tissues. II. In situ hybridization 总被引:7,自引:11,他引:7 下载免费PDF全文
M S Wyand D J Ringler Y M Naidu M Mattmuller L V Chalifoux P K Sehgal M D Daniel R C Desrosiers N W King 《The American journal of pathology》1989,134(2):385-393
Lymph nodes and spleens were collected at autopsy and by biopsy from 29 rhesus monkeys infected with simian immunodeficiency virus (SIV). Lymph nodes were classified morphologically into stages of follicular hyperplasia, follicular involution, follicular depletion with normal or expanded paracortices, follicular and paracortical depletion, granulomatous lymphadenitis, or normal. The distribution of SIV RNA was determined by in situ hybridization using a nick translated, 35S labeled, SIVmac DNA probe. Numbers of SIV-infected cells were rare during follicular hyperplasia, numerous during follicular and paracortical expansion, and rare during follicular and paracortical depletion. The splenic morphology reflected that of the lymph nodes; however, the numbers of SIV-positive cells were uniformly lower. SIV RNA was frequently restricted to a single nucleus within multinucleate syncytial cells in two cases of granulomatous lymphadenitis. These results, combined with those of a previous study, provide evidence for antigen trapping in SIV-infected hyperplastic lymph nodes and for widespread viral infection of macrophages and lymphocytes during paracortical expansion. 相似文献
995.
James E. Moore David P. Armentrout Jerry C. Parker Daniel R. Kivlahan 《Journal of behavioral medicine》1986,9(1):51-63
Fifty-seven male chronic pain patients admitted to an inpatient multimodal pain treatment program at a Midwestern Veterans Administration hospital completed the MMPI, Profile of Mood States (POMS), Tennessee Self-Concept Scale (TSCS), Rathus Assertiveness Schedule (RAS), activity diaries, and an extensive pain questionnaire. All patients were assessed both before and after treatment, and most also were assessed 2–5 months prior to treatment. No significant changes occurred during the baseline period, but significant improvements were evident at posttreatment on most variables: MMPI, POMS, TSCS, RAS, pain severity, sexual functioning, and activity diaries. MMPI subgroup membership, based on a hierarchical cluster analysis in a larger sample, was not predictive of differential treatment outcome. Possible reasons for comparable treatment gains among these subgroups, which previously have been shown to differ on many psychological and behavioral factors, are discussed.This paper originally was presented at the Fourth World Congress on Pain, Seattle, Washington, September, 1984. 相似文献
996.
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To compare the differences between proliferation and cytotoxicity of adherent natural killer (A-NK) cells cultured with serum-free medium AIMV and standard serum-containing medium in vitro, and also observe the assisting effect of IL-12 on the activation and the morphology character of IL-2-treated A-NK cells, cellular proliferation was evaluated by MTT method in vitro. The morphology of the target cells killed by A-NK cells was observed through electroscope. All of the A-NK cells cultured in serum-free medium AIMV could rapidly proliferate and keep high cytotoxicity compared with that in standard serum-containing medium. A-NK cells activated by both moderate-dose IL-2 and IL-12 were superior to the high-dose IL-2-treated A-NK cells. These data indicated that serum-free medium AIMV could replace standard serum-containing medium for culturing A-NK cells, and moderate-dose IL-2 and IL-12 could reduce side effects caused by high-dose IL-2. The study provided a new experimental basis for experimental and clinical preparation of A-NK cells. Cellular & Molecular Immunology. 相似文献
999.
Andre Tehe Chantal Maurice Debra L Hanson Marie Y Borget Nadine Abiola Matthieu Maran Daniel Yavo Zuzana Tomasik Jürg B?ni J?rg Schüpbach John N Nkengasong 《Journal of clinical virology》2006,37(3):199-205
BACKGROUND: Quantification of HIV-1 RNA remains difficult to implement in Africa. Simple and inexpensive tests for antiretroviral treatment (ART) monitoring are needed. OBJECTIVE: To evaluate an HIV-1 p24 ELISA, which combines efficient virus disruption, heat-denaturation and signal amplification, in a West African setting. STUDY DESIGN: Eighty-six HIV-1 infected patients from Abidjan, C?te d'Ivoire, were tested for p24, HIV-1 RNA, and CD4+ count at baseline, and twice within 8 months after ART initiation. RESULTS: All patients responded to ART with a minimal HIV-1 RNA drop of 0.5 log(10) at first follow-up. Forty-one (47.7%) then rebounded >0.5 log(10) or persisted above 1000 copies/mL by week 24. The predicted baseline concentration of p24 corresponding to 100,000 copies/mL of HIV-1 RNA, above which ART is recommended, was 4546 fg/mL (95% confidence interval 3148-6566). A prediction model of virologic failure, occurring after an initial response to ART, correctly classified 84% of patients using baseline p24, p24 change on therapy, and achievement of undetectable p24 as explanatory variables. The model and further bootstrap evaluation suggested a good ability to discriminate between sustained or failing virologic response to ART. CONCLUSION: HIV-1 p24 and RNA based-ART monitoring in a low-resource country dominated by HIV-1 CRF02 AG appeared comparable. 相似文献
1000.