University of Manitoba

About: University of Manitoba is a education organization based out in Winnipeg, Manitoba, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 31888 authors who have published 66592 publications receiving 2095493 citations.

Frequent somatic mutations in PTEN and TP53 are mutually exclusive in the stroma of breast carcinomas.

Abstract: We have recently shown that loss of heterozygosity of specific markers, including those at 10q23, 17p13-p15 and 16q24, can occur in the stromal and epithelial compartments of primary invasive breast carcinomas. Here, we demonstrate high frequencies of somatic mutations in TP53 (encoding tumor protein p53) and PTEN (encoding phosphate and tensin homolog) in breast neoplastic epithelium and stroma. Mutations in TP53 and PTEN are mutually exclusive in either compartment. In contrast, mutations in WFDC1 (16q24, encoding WAP four-disulfide core domain 1) occur with low frequency in the stroma.

Solution of Waveguide Discontinuities by Modal Analysis

Abstract: A general method is presented for analysis of waveguide junctions and diaphragms by summing normal modes of propagation, giving solutions for the resulting scattered modes Because interaction effects of dominant and higher-order modes between discontuities are allowed, finite-length obstructions can be studied Solutions are found without any prior assumption about the total fields existing at the discontinuities and, as a result, the formulation is applicable to a wide range of problems The technique proves to be simple and is ideally suited to computers, involving mainly the solution of sets of simultaneous linear equations Thick and thin symmetrical bifurications of a rectangular guide are studied Forward-scattered mode amplitudes and imput admittances are calculated, the computed admittance of the thin bifurication is compared with well-known results, and transverse field patterns on both sides of the junction are plotted, thus showing the accuracy of the match The results of a finite-length bifurication by a thick vane are presented for a range of lengths, the parameters of the equivalent T network being given in each case For very short lengths, the problem corresponds to an inductive strip across the guide

Incidence and prevalence of multiple sclerosis in Europe: a systematic review.

Abstract: Multiple sclerosis (MS) is the most common cause of neurological disability in young adults worldwide and approximately half of those affected are in Europe. The assessment of differential incidence and prevalence across populations can reveal spatial, temporal and demographic patterns which are important for identifying genetic and environmental factors contributing to MS. However, study methodologies vary and the quality of the methods can influence the estimates. This study aimed to systematically review European studies of incidence and prevalence of MS and to provide a quantitative assessment of their methodological quality. A comprehensive literature search was performed to obtain all original population-based studies of MS incidence and prevalence in European populations conducted and published between January 1985 and January 2011. Only peer-reviewed full-text articles published in English or French were included. All abstracts were screened for eligibility and two trained reviewers abstracted the data and graded the quality of each study using a tool specifically designed for this study. There were 123 studies that met the inclusion criteria. The study estimates were highly heterogeneous, even within regions or countries. Quality was generally higher in the more recent studies, which also tended to use current diagnostic criteria. Prevalence and incidence estimates tended to be higher in the more recent studies and were higher in the Nordic countries and in northern regions of the British Isles. With rare exceptions, prevalence and incidence estimates were higher in women with ratios as high as 3:1. Few studies examined ethnicity. Epidemiological data at the national level was uncommon and there were marked geographical disparities in available data, with large areas of Europe unrepresented and other regions well-represented in the literature. Only 37% of the studies provided standardized estimates. Despite the breadth of the literature on the epidemiology of MS in Europe, inter-study comparisons are hampered by the lack of standardization. Further research should focus on regions not yet studied and the evaluation of ethnic differences in MS prevalence and incidence. National-level studies using current diagnostic criteria, validated case definitions and similar age- and sex-standardization would allow better geographical comparisons.