24 research outputs found
Nitric oxide of human colorectal adenocarcinoma cell lines promotes tumour cell invasion
The present study investigates the role of nitric oxide and the involvement of nitric oxide synthase II isoform on the invasion of human colorectal adenocarcinoma cell lines HRT-18 and HT-29. HRT-18 cells, which constitutively express nitric oxide synthase II mRNA were three-fold more invasive in a Matrigel® invasion assay than nitric oxide synthase II mRNA negative HT-29 cells. Treatment of HT-29 cells with the nitric oxide donor Deta NONOate (50 nM) as well as induction of nitric oxide synthase II mRNA and production of endogenous nitric oxide by inflammatory cytokines (IFN-γ and IL-1α) increased the invasiveness of HT-29 cells by approximately 40% and 75%, respectively. In HT-29 cells nitric oxide synthase II mRNA was also induced in co-culture with human monocytes. The invasiveness of HRT-18 cells and stimulated HT-29 cells was partly inhibited by the nitric oxide synthase II inhibitor 1400 W. These results show that nitric oxide increases the invasion of human colorectal adenocarcinoma cell lines HRT-18 and HT-29, and the involvement of nitric oxide synthase II isoform in tumour cell invasion. Therefore, the production of nitric oxide and secretion of pro-inflammatory cytokines by tumour-associated macrophages, which in turn induce nitric oxide synthase II isoform in tumour cells, promotes tumour cell invasiveness
3-D object mesh geometry compression with vector quantization
IEEE 12th Signal Processing and Communications Applications Conference -- APR 28-30, 2004 -- Kusadasi, TURKEYWOS: 000225861200076In this study, the objective is to develop a new combined method for efficient compression of classical 3-D object mesh representation. This can be realized in two primary steps: Mesh connectivity coding and data (geometry) compression. For realizing the first step, the algorithm of Isenburg [1] has been employed. For the second step, vector quantization methods have been used to compress the vertex coordinate. The difference between our study and the others is that our study uses ECVQ method for vertex coordinate compression to improve the results.IEEE, Tubitak, Istanbul Teknik Univ, Aselsan, Profile Telre, TURCom, Sgi, Datacore, Divi
3-D object mesh geometry compression with vector quantization [3-B Nesne Bilgilerinin Vektör Nicemleme Yöntemleri ile Sikiştirilmasi]
IEEE;TUBITAK;Istanbul Teknik Universitesi;aselsan;Profilo Telr@Proceedings of the IEEE 12th Signal Processing and Communications Applications Conference, SIU 2004 -- 28 April 2004 through 30 April 2004 -- Kusadasi -- 64722In this study, the objective is to develop a new combined method for efficient compression of classical 3-D object mesh representation. This can be realized in two primary steps: Mesh connectivity coding and data (geometry) compression. For realizing the first step, the algorithm of Isenburg has been employed. For the second step, vector quantization methods have been used to compress the vertex coordinate. The difference between our study and the others is that our study uses ECVQ method for vertex coordinate compression to improve the results. © 2004 IEEE
Compressing mesh geometry using spectral methods and a set partitioning approach [Spektral yöntemler ve küme bölüntüleme yaklaşimlariyla 3B nesne bilgilerinin sikiştirilmasi]
2006 IEEE 14th Signal Processing and Communications Applications -- 17 April 2006 through 19 April 2006 -- Antalya -- 69461Elektronik Mühendisligi Bölümü. We propose a mesh geometry coder that utilizes spectral methods and a set partitioning approach for coding the spectral coefficients. The spectral method of [1] not only achieved high rate-distortion performance on irregular meshes, but also allowed progressive transmission of meshes by truncating the coefficient vector and performing reconstruction with a small subset of coefficients that contain most of the total energy. In this paper, mesh geometry is projected onto an orthonormal basis that is derived from the mesh topology as in [1], and the spectral coefficients are coded with the set partitioning sorting algorithm of [2]. Since the method achieves implicit bit allocation to the spectral coefficients of the three coordinates and efficiently codes the significant coefficient location information by jointly coding the zeroes in the bit planes of these coefficients the rate- distortion performance of the proposed method is superior to that of [1] as demonstrated by our experiments on common irregular meshes. The generated bit stream is also truly embedded. © 2006 IEEE
Donor CD4 T cells convert mixed to full donor T-cell chimerism and replenish the CD52-positive T-cell pool after alemtuzumab-based T-cell-depleted allo-transplantation
Donor lymphocyte infusions (DLI) are used to resolve mixed T-cell chimerism (TCC) after allo-SCT despite a substantial risk of GVHD. We analyzed the impact of prophylactic CD8-depleted (CD8(depl)) DLI in 20 recipients of anti-CD52 alemtuzumab in vivo T-cell-depleted allografts with declining donor TCC after day +60. A total of 13 patients received CD8(depl) DLI and 7 patients did not. All but one of the DLI patients converted to complete donor T-cell chimeras, whereas only one non-DLI patient converted spontaneously. DLI induced transient acute GVHD in five and extensive chronic GVHD in two patients. These data suggest the use of CD8(depl) DLI as an effective treatment for mixed TCC, particularly in patients at high risk for GVHD. We also observed that the majority of reconstituting donor-derived T cells after alemtuzumab conditioning were CD52-negative. CD8(depl) DLI significantly increased the proportion of CD52-positive CD4 T cells, whereby their beneficial effect on reconstituting the post-transplant T-cell repertoire was shown