Search results for "Animal"
showing 10 items of 22159 documents
Muscleblind, BSF and TBPH are mislocalized in the muscle sarcomere of a Drosophila myotonic dystrophy model
2012
SummaryMyotonic dystrophy type 1 (DM1) is a genetic disease caused by the pathological expansion of a CTG trinucleotide repeat in the 3' UTR of the DMPK gene. In the DMPK transcripts, the CUG expansions sequester RNA-binding proteins into nuclear foci, including transcription factors and alternative splicing regulators such as MBNL1. MBNL1 sequestration has been associated with key features of DM1. However, the basis behind a number of molecular and histological alterations in DM1 remain unclear. To help identify new pathogenic components of the disease, we carried out a genetic screen using a Drosophila model of DM1 that expresses 480 interrupted CTG repeats, i(CTG)480, and a collection of…
Bio-silica and bio-polyphosphate: applications in biomedicine (bone formation)
2012
Bio-silica represents the main mineral component of the sponge skeletal elements (siliceous spicules), while bio-polyphosphate (bio-polyP), a multifunctional polymer existing in microorganisms and animals acts, among others, as reinforcement for pores in cell membranes. These natural inorganic bio-polymers, which can be readily prepared, either by recombinant enzymes (bio-silica and bio-polyP) or chemically (polyP), are promising materials/substances for the amelioration and/or treatment of human bone diseases and dysfunctions. It has been demonstrated that bio-silica causes in vitro a differential effect on the expression of the genes OPG and RANKL, encoding two mediators that control the …
Influence of sutures configuration on the strength of tendon-patch joints for rotator cuff tears treatment
2019
Abstract Purpose Massive rotator cuff tears are common in the aging population. The incidence of failed rotator cuff repairs is still quite high, especially in the treatment of full-thickness tears or revision repairs. In this context, natural and synthetic meshes can be used as augmentation scaffolds or as devices to close the gap between a retracted tendon and the bone. The purpose of this work is to evaluate the ultimate tensile strength of different tendon-patch joints in order to consider their use in the treatment of massive cuff tears. Materials and methods Porcine tendons and a synthetic low-density polypropylene mesh have been used. A preliminary study on the tensile strength of te…
Enhanced prolylhydroxylase activity in the posterior annulus fibrosus of canine intervertebral discs following long-term running exercise
2010
The effect of long-term excercise on the intervertebral disc collagen concentration (hydroxyproline), collagen-synthesizing enzymes (prolyl-4-hydroxylase, PH, and galactosyl-hydroxylysyl glucosyltransferase, GGT) and hydroxypyridinium crosslinks was studied in ten female beagle dogs. The dogs were run on a treadmill for 1 year starting at the age of 15 weeks. The daily running distance was gradually increased to 40km, which distance the dogs ran for the final 15 weeks. Ten untrained dogs from the same breeding colony served as controls. The nucleus pulposus and anterior and posterior halves of the annulus fibrosus of C2-3, T10-12, L4-5 disc segments were analysed. Crosslinks were measured f…
Non-conventional forms of HLA-B27 are expressed in spondyloarthritis joints and gut tissue
2016
Objectives Human leukocyte antigen (HLA)-B27 (B27) is the strongest genetic factor associated with development of Ankylosing Spondylitis and other spondyloarthropathies (SpA), yet the role it plays in disease pathogenesis remains unclear. We investigated the expression of potentially pathogenic non-conventional heavy chain forms (NC) of B27 in synovial and intestinal tissues obtained from SpA patients. We also determined the presence of NC-B27 in joints, lymphoid and gastrointestinal tissue from B27 transgenic (TG1) rats with M.tuberculosis-induced SpA. Methods Expression of NC-B27 in human SpA joints and gut and in (21-3 × 283-2)F1 HLA-B27/Huβ2m rat tissue was determined by immunohistochem…
Kinematics of the ulna during pronation and supination in a cadaver study: implications for elbow arthroplasty
2003
Objective. Aim of this study was to exactly describe and quantify kinematics of the ulna during pro- and supination. Design. Biomechanical study in fresh frozen cadavers. Background. A previous MRI study revealed a varus/valgus motion of the ulna averaging 7.1° during pro-/supination. Axial rotation, however, could not be quantified. Methods. Sixteen arms were examined in a new apparatus that fixed the humerus on a template and allowed forearm rotation. Motion of a Kirschner wire placed in the ulna was recorded in steps of 30° by two perpendicularly arranged charge coupled device cameras during pro- and supination. Results. From supination to pronation the ulna showed a semi-lunar evasive m…
Aberrant glycosylation of alpha-dystroglycan causes defective binding of laminin in the muscle of chicken muscular dystrophy.
2005
Dystroglycan is a central component of dystrophin-glycoprotein complex that links extracellular matrix and cytoskeleton in skeletal muscle. Although dystrophic chicken is well established as an animal model of human muscular dystrophy, the pathomechanism leading to muscular degeneration remains unknown. We show here that glycosylation and laminin-binding activity of alpha-dystroglycan (alpha-DG) are defective in dystrophic chicken. Extensive glycan structural analysis reveals that Galbeta1-3GalNAc and GalNAc residues are increased while Siaalpha2-3Gal structure is reduced in alpha-DG of dystrophic chicken. These results implicate aberrant glycosylation of alpha-DG in the pathogenesis of mus…
Ritz Solution for Transient Analysis of Variable-Stiffness Shell Structures
2020
The dynamic response of thin-walled structures is driven by mass and stiffness distribution. As such, variable-stiffness (VS) composites offer opportunities to tune structural dynamic responses. To this extent, efficient analysis tools become increasingly important for structural analysis and design purposes. In this work, an efficient and versatile Ritz method for free vibrations and linear transient analysis of VS doubly curved shell structures is presented. VS shell structures are modeled as an assembly of shell-like domains. The shell kinematics is based on the first-order shear deformation theory, and no further assumption is made on the shallowness or on the thinness of the structure.…
Stiffness and Reinforcement Effect of electrical Resistance Strain Gauges
2007
: The increasing use of low-modulus materials, on which the reinforcement effect of the electrical resistance strain gauge is not negligible, has re-opened the research interest into this issue. This study deals with the evaluation of stiffness, and of the strain gauge Young's modulus involved in the estimation of both the global and the local reinforcement effect; the relationship between the strain gauge stiffness and the local reinforcement effect is also analysed. In particular, the experimental technique used to determine the stiffness of some commercial strain gauges is described. The results show that the strain gauge stiffness alone does not permit an accurate evaluation of the loc…
<p><strong>A new genus of Phaneropterinae (Orthoptera: Ensifera: Tettigoniidae) </strong><strong>from Central Africa</stro…
2014
The new genus Pseudoplangia is described for Plangia laminifera Karsch, 1896. Its general aspect is similar to that of the genus Plangia Stal, 1873, but it differs remarkably in the vertex width, in the shape of eyes, that are oval and elongate, in the length of mid femora, that are shorter than pronotum length, in the shape of fore and mid legs that are very much laterally compressed, and in the presence of broad-based spines on the hind tibiae.