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C Cases (c + case)
Selected AbstractsNear-diploid and near-triploid human sporadic colorectal adenocarcinomas differ for KRAS2 and TP53 mutational statusGENES, CHROMOSOMES AND CANCER, Issue 2 2003Walter Giaretti Mutations of the KRAS2 protoncogene and inactivation of the TP53 oncosuppressor gene have been suggested to contribute to chromosomal instability (CIN) and aneuploidy in colorectal cancer (CRC). Previous work has also shown that the degree of DNA ploidy [DNA index (DI)], as obtained by flow cytometry in CRC, is non-randomly distributed and, in particular, that DI near-diploid and near-triploid values are well separated by a low-probability valley region. At present, it is not known whether a relationship exists between DI and the mutational status of KRAS2 and TP53. Multiple samples obtained from 35 human sporadic CRCs have been used to provide nuclei suspensions for flow cytometric analysis and sorting of specific DI subpopulations. Sorted nuclei were then used to analyze the high-microsatellite-instability (MSI-H) phenotype and the mutation spectrum of the KRAS2 and TP53 genes. A single MSI-H case was detected. There were 6 DNA diploid (DI = 1) and 29 aneuploid (DI , 1) CRCs, with the DI aneuploid cases non-randomly subdivided in 9 near-diploid (DI , 1 and DI , 1.4), 8 near-triploid (1.4 < DI < 1.6), and 12 high-aneuploid (DI , 1.6) cases. Proximal CRCs were more often DNA diploid and near-diploid than distal ones, and Dukes' C cases were more commonly high-aneuploid than Dukes' B. Moreover, the incidence of mutations of the KRAS2 and TP53 genes was lowest among the DNA near-triploid subpopulations and highest among the near-diploid ones. We suggest that DNA near-diploid and near-triploid subpopulations in human sporadic CRC reflect different genetic mechanisms of CIN and have a potentially different clinical behavior. © 2003 Wiley-Liss, Inc. [source] Methionine-enkephalin secreted by human colorectal cancer cells suppresses T lymphocytesCANCER SCIENCE, Issue 3 2009Hitoshi Ohmori The role of methionine-enkephalin (MENK) as an immunomodulator in colorectal carcinomas (CRC) was examined. MENK was produced in CT26, IEC6A, Colo320, and HT29 CRC cell lines but not in IEC6 intestinal cells. MENK secretion was associated with tumorigenicity and metastasis of CRC cells in syngeneic rodent models. The MENK concentration in subcutaneous tumors of CT26 and IEC6A CRC cells exhibited an inverse correlation with the number of tumor-infiltrating T lymphocytes. MENK inhibited the growth of MOLT-4 T-lymphoblastic cells in a dose-dependent manner. Furthermore, it increased the phosphorylation level of c-Jun N-terminal kinase and induced apoptosis in MOLT-4 cells. MENK-induced apoptosis was abrogated by a c-Jun N-terminal kinase inhibitor. Immunohistochemical analysis revealed moderate to strong expression of MENK in 33 (54%) of 61 CRC. MENK expression was associated with Dukes' staging, nodal metastasis, and liver metastasis. The MENK concentration in tumor tissues was higher in Dukes' C cases than in Dukes' B cases. MENK expression was associated with tumor-infiltrating T lymphocytes, especially those belonging to the CD4+ subset. These findings suggest that MENK secreted by CRC cells caused escape of the host from the effects of immunity. (Cancer Sci 2009; 100: 497,502) [source] Intravenous catheter infections associated with bacteraemia: a 2-year study in a University HospitalCLINICAL MICROBIOLOGY AND INFECTION, Issue 5 2004M. Paragioudaki Abstract The aim of this retrospective study was to assess the incidence and aetiology of central and peripheral venous catheter (C/PVC) infections during a 2-year period (1999,2000) and to determine the susceptibility of isolated microorganisms to various antimicrobial agents. Catheter tips were processed using the semiquantitative method and blood cultures were performed with the BacT/Alert automated system. Antibiotic susceptibilities were performed by disk agar diffusion and MICs were determined by Etest, according to NCCLS standards. During the study period, samples from 1039 C/PVC infections were evaluated, yielding 384 (37.0%) positive cultures. Blood cultures were also available from 274 patients, of which 155 (56.6%) yielded the same microorganism as from the catheter. No bloodstream infections were detected in 104 C/PVC-positive cases. Methicillin-resistant coagulase-negative staphylococci were the most frequent isolates, followed by Gram-negative bacteria, especially Pseudomonas aeruginosa. Resistance to glycopeptides among staphylococci and enterococci was not detected, whereas 60% of Gram-negative bacilli were resistant to ,-lactams. [source] Flow reversal over a natural pool,riffle sequence: a computational studyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 7 2003Zhixian Cao Abstract A computational study is presented on the hydraulics of a natural pool,rif,e sequence composed of mixed cobbles, pebbles and sand in the River Lune, northern England. A depth-averaged two-dimensional numerical model is employed, calibrated with observed data at the ,eld site. From the computational outputs, the occurrence of longitudinally double peak zones of bed shear stress and velocity is found. In particular, at low discharge there exists a primary peak zone of bed shear stress and velocity at the rif,e tail in line with the local maximum energy slope, in addition to a secondary peak at the pool head. As discharge increases, the primary peak at the rif,e tail at low ,ow moves toward the upstream side of the rif,e along with the maximum energy slope, showing progressive equalization to the surrounding hydraulic pro,les. Concurrently, the secondary peak, due to channel constriction, appears to stand at the pool head, with its value increasing with discharge and approaching or exceeding the primary peak over the rif,e. The existence of ,ow reversal is demonstrated for this speci,c case, which is attributable to channel constriction at the pool head. A dynamic equilibrium model is presented to reconstruct the pool,rif,e morphology. A series of numerical modelling exercises demonstrates that the pool,rif,e morphology is more likely produced by shallow ,ows concentrated with coarse sediments than deep ,ows laden with low concentrations of ,ne sediments. It is concluded that channel constriction can, but may not necessarily, lead to competence reversal, depending on channel geometry, ,ow discharge and sediment properties. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||