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Peculiar Aspect (peculiar + aspect)
Selected AbstractsInterstitial Cajal-like cells in rat mesentery: an ultrastructural and immunohistochemical approachJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2008M. E. Hinescu Abstract Interstitial Cajal-like Cells (ICLC) were recently recognized in a plethora of non-digestive organs. Here, we describe a cell type of rat mesentery sharing ultrastructural and immunohistochemical features with ICLC. Mesenteric ICLC were demonstrated by transmission electron microscopy (TEM) and further tested by light microscope immunohistochemistry. The cell described here fulfils the TEM diagnostic criteria accepted for ICLC: location in the connective interstitium; close vicinity to nerves, capillaries and other interstitial cells; characteristic long, moniliform cell processes; specialized cell-to-cell junctions; caveolae; mitochondria at 5,10% of cytoplasmic volume; rough endoplasmic reticulum at about 1,2%; intermediate and thin filaments, microtubules; undetectable thick filaments. The processes of this mesenteric ICLC were particularly long, with a mean length of 24.91 ,m (10.27,50.83 ,m), and a convolution index of 2.32 (1.37,3.63) was calculated in order to measure their potential length. Mean distances versus main target cells of ICLC,nerve bundles, vessels, adipocytes and macrophages,were 110.69, 115.80, 205.07 and 34.65 nm, respectively. We also tested the expression of CD117/c-kit, CD34, vimentin, ,-smooth muscle actin, nestin, NK-1, tryptase and chymase and the antigenic profile of the mesenteric ICLC was comparable if not identical with that recently observed in ICLC from other extra-digestive tissues. Due to the peculiar aspect of the mesenteric ICLC processes it can be hypothesized that these cells form a three-dimensional network within the mesentery that is at the same time resistant and deformable following stretches consequent to intestine movements, mainly avoiding blood vessels closure or controlling blood vessels rheology. It remains, however, to be established if and how such cells are connected with the archetypal enteric ICC. [source] Igloo-like prepuce: a peculiar aspect of smooth-muscle hamartoma of the genitalia?JOURNAL OF CUTANEOUS PATHOLOGY, Issue 2 2005Paolo Sbano Histopathological examination consisting of classical microscopy, immuno-histochemistry and electronmicroscopy of the surgical material provided insights into the etiopathogenesis of this rare disease. [source] Etiopathogenic role of HLA-B27 alleles in ankylosing spondylitisINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 3 2005Nurullah AKKOC Abstract HLA-B27 is the major genetic susceptibility factor for ankylosing spondylitis (AS). However, its precise role in the pathogenesis of AS still remains unclear, even though its gene has been cloned and sequenced, and its crystallographic structure has been defined. Arthritogenic peptide and molecular mimicry hypotheses propose mechanisms related to an antigen-presenting function of HLA-B27 to be responsible for disease development. However, peculiar aspects of its immunobiology, such as its misfolding and heavy chain dimerization raise the possibility of involvement of pathogenic mechanisms unrelated to its physiological function. Moreover, HLA-B27 is not a single allele, but a family of 31 different alleles, named HLA-B*2701 to HLA-B*2727. Studies worldwide indicate that the relatively common alleles (subtypes) HLA-B*2705, B*2704, and B*2702 are strongly associated with AS, whereas HLA-B*2706 which is prevalent in South-east Asia and HLA-B*2709 which is prevalent on the Italian island of Sardinia, seem to lack such an association. The distinction between the disease-associated subtypes and those that are not associated, may provide clues to the actual role of HLA-B27 in disease pathogenesis. B*2706 differs from B*2704 by only two residues, and B*2709 differs from B*2705 by only one residue. Moreover, both B*2706 and B*2709 bind an endogenous peptide (derived from vasoactive intestinal peptide type 1 receptor) and also an exogenous peptide (latent membrane protein 2 of Epstein-Barr virus) but in two drastically diverse conformations. These recent X-ray diffraction studies of individual peptides in the context of different HLA-B27 alleles broaden our perception of the possible pathogenetic role of this molecule in the development of AS and related spondyloarthopathies. In summary, the pathogenetic role of HLA-B27 in AS seem to be quite heterogenous, and cannot be explained by a single mechanism, and new ideas have been raised based on the aberrant immunobiologic features of HLA-B27. [source] On some peculiar aspects of the constructive theory of point-free spacesMLQ- MATHEMATICAL LOGIC QUARTERLY, Issue 4 2010Giovanni Curi Abstract This paper presents several independence results concerning the topos-valid and the intuitionistic (generalised) predicative theory of locales. In particular, certain consequences of the consistency of a general form of Troelstra's uniformity principle with constructive set theory and type theory are examined (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||