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Parallel Sections (parallel + section)
Selected AbstractsHepatocarcinogenesis in Female Mice With Mosaic Expression of Connexin32HEPATOLOGY, Issue 3 2000Oliver Moennikes Mice deficient for connexin32 (Cx32), the major gap junction forming protein in liver, are highly susceptible to hepatocarcinogenesis. Because the Cx32 gene is located on the X-chromosome, heterozygous females show mosaicism with respect to Cx32 expression; this enables their use in studying the effect of Cx32-deficiency in a mixed Cx32-plus/Cx32-minus environment in vivo. Female C3H/He mice (Cx32+/+) were crossed with Cx32-deficient C57BL/129Sv males (Cx32Y/- ) to yield F1 females heterozygous with respect to Cx32 (Cx32+/,). Patches of hepatocytes were observed in normal liver that either expressed Cx32 or failed to express the protein. The mean fraction of Cx32-negative tissue in liver was about 60% and did not change significantly with age of mice. Neoplastic liver lesions, induced in weanling mice, were identified in serial liver sections by their deficiency in glucose-6-phosphatase staining. Parallel sections were used for immunohistochemical demonstration of Cx32 protein. Smaller lesions were either homogenously Cx32-negative or showed unchanged to slightly elevated levels of Cx32 protein. There were no major differences in number and size distribution between lesions of these 2 phenotypes. In addition, larger lesions were mostly Cx32-negative but often contained embedded patches of Cx32-positive cells. Staining for the proliferation-associated nuclear antigen Ki-67 did not reveal significant differences between Cx32-negative and Cx32-positive hepatocytes in Cx32-mosaic tumors. This suggests that expression of Cx32 within a subpopulation of tumor cells does not negatively regulate their growth nor does it seem to affect the proliferation of their directly neighboring Cx32-negative counterparts. [source] Role of Chlamydia pneumoniae -infected macrophages in atherosclerosis developments of the carotid arteryNEUROPATHOLOGY, Issue 1 2003Satoshi Kuroda Chlamydia pneumoniae (C. pneumoniae) infection has been recently accepted as an important cause of atherosclerosis. However, the precise mechanisms remain unclear. The present study was aimed to clarify the distribution link among C. pneumoniae, chlamydial HSP 60, and activated macrophages. Atheromatous carotid plaques were obtained from 40 consecutive carotid endarterectomies (CEA). The specimens were prepared for HE and elastica,van Gieson staining. Parallel sections were stained immunocytochemically with monoclonal antibodies for a C. pneumoniae -specific antigen, chlamydial HSP 60, activated macrophages, and smooth muscle cells. Immunoreactivity for the C. pneumoniae -specific antigen was observed within the endothelial cells, activated macrophages, and smooth muscle cells in 36 of 40 specimens (90%). Chlamydial HSP 60 was found in all specimens positive for the C. pneumoniae -specific antigen, and mainly co-localized with the C. pneumoniae -specific antigen within the activated macrophages. The present results suggest that C. pneumoniae is a key microbial organ that causes atheroma developments in the carotid artery. Chlamydia pneumoniae -infected macrophages may come into the arterial intima and mediate inflammatory and autoimmune processes through the production of chlamydial HSP 60, leading to atherosclerosis. [source] Analysis of HER2 expression in primary urinary bladder carcinoma and corresponding metastasesBJU INTERNATIONAL, Issue 7 2005Truls Gĺrdmark OBJECTIVE To evaluate the expression of HER2 receptors (previously reported to be over-expressed in malignant urothelium) in both primary tumours and metastases of transitional cell cancer, using two different staining methods and two different scoring techniques, considering the potential use of these receptors as targets for planned systemic anti-HER2 nuclide-based treatment. MATERIALS AND METHODS HER2 expression was evaluated with two different immunohistochemical methods in 90 patients with primary urinary bladder cancer tumours and corresponding metastases. Sections were first stained with the commercially available breast cancer test kit (HercepTest®, Dako, Glostrup, Denmark). Parallel sections were then stained with a modified HercepTest procedure. Two different evaluation criteria were compared; the HercepTest score that requires ,,10% stained tumour cells (as for breast cancer) and a proposed ,Target score' that requires >67% stained tumour cells. The latter score is assumed to be preferable for HER2-targeted radionuclide therapy. RESULTS Using the HercepTest kit, the Target score gave lower fractions of positive primary tumours and metastases than the HercepTest score. The modified HercepTest staining procedure and Target score gave high HER2 values in 80% of primary tumours and 62% of metastases, which is considerably more than that obtained with the HercepTest staining and score. There was a significant decrease in HER2 positivity with increasing distance from the primary tumour. In nine sentinel-node metastases assessed, all but one were HER2-positive. Considering all regional metastases, 74% were positive, and of distant metastases, 47%; 72% of the patients with positive primary tumours also expressed HER2 in their metastases. CONCLUSIONS When combining the modified HercepTest with customised evaluation criteria, more HER2-positive tumours were diagnosed. The degree of HER2 down-regulation was significantly higher in distant than in regional metastases. HER2-targeted therapy may be an alternative or complementary to other methods in the future treatment of metastatic urinary bladder carcinoma. [source] Performance comparison of MPI and OpenMP on shared memory multiprocessorsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 1 2006Géraud Krawezik Abstract When using a shared memory multiprocessor, the programmer faces the issue of selecting the portable programming model which will provide the best performance. Even if they restricts their choice to the standard programming environments (MPI and OpenMP), they have to select a programming approach among MPI and the variety of OpenMP programming styles. To help the programmer in their decision, we compare MPI with three OpenMP programming styles (loop level, loop level with large parallel sections, SPMD) using a subset of the NAS benchmark (CG, MG, FT, LU), two dataset sizes (A and B), and two shared memory multiprocessors (IBM SP3 NightHawk II, SGI Origin 3800). We have developed the first SPMD OpenMP version of the NAS benchmark and gathered other OpenMP versions from independent sources (PBN, SDSC and RWCP). Experimental results demonstrate that OpenMP provides competitive performance compared with MPI for a large set of experimental conditions. Not surprisingly, the two best OpenMP versions are those requiring the strongest programming effort. MPI still provides the best performance under some conditions. We present breakdowns of the execution times and measurements of hardware performance counters to explain the performance differences. Copyright © 2005 John Wiley & Sons, Ltd. [source] The relationship of proliferating cell density at the invasive tumour front with prognostic and risk factors in human oral squamous cell carcinomaJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 4 2004Vijay Tumuluri BACKGROUND:, We hypothesise that the density of proliferating cells at the invasive tumour front (ITF) has a positive relationship with prognostic and risk factors in human oral squamous cell carcinoma (SCC). METHODS:, Tissues from 47 human oral SCC specimens were collected and stained with a monoclonal antibody directed against the Ki-67 antigen using a horseradish peroxidase based two-step immunostaining method. Counting was performed on two parallel sections at the ITF using an image analyser. The Ki-67 labelling index (LI) was determined by measuring the number of nuclei/mm2 of epithelium. RESULTS:, Our results show that the density of proliferating cells is related to clinical staging, with advanced stage of disease having a significantly higher Ki-67 LI compared with early stage of disease (2111 ± 905 vs. 1908 ± 913; P = 0.03). Importantly, this study shows that tumours that have metastasised have a significantly higher Ki-67 LI than tumours where distant metastasis was not detected (3257 ± 650 vs. 1966 ± 881; P < 0.0001). CONCLUSIONS:, Cell proliferation, as measured by the Ki-67 LI at the ITF, has a positive relationship with clinical staging, tumour thickness, smoking status of the patient and alcohol consumption. Further, we suggest that a multicenter study with a large cohort of patients is indicated to fully elucidate whether cell proliferation at the ITF is directly related to patient survival. [source] New micromachined interdigital coplanar waveguideMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2007Xiaofeng Sun Abstract A novel interdigital coplanar waveguide (CPW) has been designed and fabricated and its characteristics have been studied as a function of transmission line parameters. In this interdigital CPW, the ground conductors are thickened by micromachining techniques, which are helpful for reducing the interference between the adjacent parallel sections of center conductor. Within the frequency range from 5 to 20 GHz, the return loss of this structure has two minimal values whose positions change with the structural parameters. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1007,1010, 2007; Published online in Wiley InterScience (www.interscience.wiley.com).DOI 10.1002/mop.22336 [source] Proapoptotic and antiapoptotic markers in cutaneous T-cell lymphoma skin infiltrates and lymphomatoid papulosisBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2001H. Nevala Background In cutaneous T-cell lymphoma (CTCL) lesions, both reactive T cells and malignant T cells intermingle. The disease progression is mostly slow. Recent evidence suggests that even if clinical remission is reached, malignant cells persist and a relapse follows sooner or later. To what extent tumour cell apoptosis occurs in the skin lesions either due to the reactive T cells or to therapeutic efforts is not known. Objectives To determine the extent of tumour cell apoptosis and the expression of proapoptotic and antiapoptotic markers in serial skin lesion samples from patients with CTCL, and to compare the findings with those in patients with lymphomatoid papulosis (LyP). Methods Thirty-four skin samples were obtained from 12 patients with CTCL at the time of diagnosis and at a mean of 1·6, 3 and 6 years later. The patients received psoralen plus ultraviolet A (PUVA), electron beam or cytostatic treatments. In addition, fresh post-treatment samples from three patients with CTCL undergoing PUVA therapy were obtained. For comparison, skin biopsies of five patients with LyP were studied. Immunohistochemical demonstration of the expression of the following markers was performed on formalin-fixed skin sections: Fas (CD95), Fas ligand (FasL), bcl-2, granzyme B, the tumour-suppressor protein PTEN and the effector caspase, caspase-3. The malignant cells were identified morphologically, and apoptotic cells were identified with the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling method on parallel sections. Results In untreated CTCL lesions, apoptotic lymphocytes were extremely rare, and no increase in the number of apoptotic cells was observed after any of the treatments used. In LyP, apoptotic cells were more frequent, comprising on average 5% of the infiltrate. The apoptosis-associated markers Fas, FasL, caspase-3 and granzyme B were expressed by morphologically neoplastic cells in CTCL and by large atypical cells in LyP, with no significant differences. However, only a few reactive cells in CTCL infiltrates expressed granzyme B while about 10% of the corresponding cells were positive in LyP. The expression of antiapoptotic bcl-2 was more frequent in CTCL than in LyP, while PTEN expression was high in both instances. The number of bcl-2+ cells tended to decrease after therapy. When comparing the findings between the first and the last samples, a decrease in the number of bcl-2+ cells and an increase in Fas+ cells was associated with disease progression, despite therapy, while the opposite was true for remissions. Conclusions Apoptosis was found to be a rare event in CTCL lesions irrespective of preceding therapy. During patient follow-up, no significant differences in the expression of apoptotic markers was observed while in most cases a lower level of antiapoptotic bcl-2 expression was observed after all types of therapies and in association with disease progression when compared with high expression in the untreated lesions. The absence of apoptosis and high expression of bcl-2 together with a low expression of apoptosis-inducing granzyme B in the reactive lymphocytes in CTCL could explain the chronic nature of the disease and the poor response to therapy, while the more frequent occurrence of granzyme B and apoptosis together with a lower level of expression of bcl-2 by the large atypical cells in LyP could contribute to the favourable outcome of the latter. [source] | ||||||||||