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141.
Ndrepepa G Karch MR Schneider MA Weyerbrock S Schreieck J Deisenhofer I Zrenner B Schömig A Schmitt C 《Journal of cardiovascular electrophysiology》2002,13(6):525-532
INTRODUCTION: Atrial fibrillation (AF) in the left atrium (LA) is poorly defined in terms of regional differences in the degree of organization, characteristics of paroxysmal and persistent variants, and electrophysiologic events that develop at the onset of episodes. METHODS AND RESULTS: The study population consisted of 21 patients (15 men and 6 women; mean age 58+/-9.4 years) with paroxysmal (10 patients) or persistent (11 patients) AF. Mapping of the LA during sustained episodes and the onset of AF was performed with a 64-electrode basket catheter. At the onset of AF, repetitive beats starting with atrial premature complexes and ending with generation of the earliest fibrillatory activity were defined as intermediary rhythm. Patients with paroxysmal AF had longer AF cycle lengths and more pronounced regional differences than patients with persistent AF. In total, AF cycle lengths in the LA in patients with persistent AF were 20% shorter than in patients with paroxysmal AF. Initiation of AF was preceded by an intermediary rhythm of 5.5+/-2.5 cycles (6.3+/-2.7 cycles in paroxysmal AF vs 4.2+/-1.0 cycles in persistent AF; P = 0.026). At the onset of AF, the earliest generators of fibrillatory activity were located more frequently in the posterior wall of the LA. CONCLUSION: AF in the LA displays substantial regional differences in terms of AF cycle lengths and degree of organization. Patients with persistent AF have shorter cycle lengths and a higher degree of disorganized activity than patients with paroxysmal AF. Intermediary rhythms play an important role in initiation of AF via activation of generator regions in the LA. 相似文献
142.
Callejo A Culi J Guerrero I 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(3):912-917
The Hedgehog (Hh) family of secreted signaling proteins has a broad variety of functions during metazoan development and implications in human disease. Despite Hh being modified by two lipophilic adducts, Hh migrates far from its site of synthesis and programs cellular outcomes depending on its local concentrations. Recently, lipoproteins were suggested to act as carriers to mediate Hh transport in Drosophila. Here, we examine the role of lipophorins (Lp), the Drosophila lipoproteins, in Hh signaling in the wing imaginal disk, a tissue that does not express Lp but obtains it through the hemolymph. We use the up-regulation of the Lp receptor 2 (LpR2), the main Lp receptor expressed in the imaginal disk cells, to increase Lp endocytosis and locally reduce the amount of available free extracellular Lp in the wing disk epithelium. Under this condition, secreted Hh is not stabilized in the extracellular matrix. We obtain similar results after a generalized knock-down of hemolymph Lp levels. These data suggest that Hh must be packaged with Lp in the producing cells for proper spreading. Interestingly, we also show that Patched (Ptc), the Hh receptor, is a lipoprotein receptor; Ptc actively internalizes Lp into the endocytic compartment in a Hh-independent manner and physically interacts with Lp. Ptc, as a lipoprotein receptor, can affect intracellular lipid homeostasis in imaginal disk cells. However, by using different Ptc mutants, we show that Lp internalization does not play a major role in Hh signal transduction but does in Hh gradient formation. 相似文献
143.
Juan Ramn Tejedor Clara Bueno Meritxell Vinyoles Paolo Petazzi Antonio Agraz-Doblas Isabel Cobo Raúl Torres-Ruiz Gustavo F. Bayn Raúl F. Prez Sara Lpez-Tamargo Francisco Gutierrez-Agüera Pablo Santamarina-Ojeda Manuel Ramírez-Orellana Michela Bardini Giovanni Cazzaniga Paola Ballerini Pauline Schneider Ronald W. Stam Ignacio Varela Mario F. Fraga Agustín F. Fernndez Pablo Menndez 《The Journal of clinical investigation》2021,131(13)
144.
Ricardo K. Kalil Altamir Monteiro Jr. Maria Isabel Lima Eni B. Silveira Francineide S. S. Foltran Carlos E. Speck Martins 《Ultrastructural pathology》2013,37(1):45-50
Macrophagic myofasciitis (MMF) is an inflammatory myopathy related to aluminum-containing vaccines. Described in 1998, most cases were reported in adults, with only 22 cases being reported in children. Three children aged between 13 months and 3½ years were investigated in our institution for neuromuscular symptoms. They underwent thorough clinical, familial, and laboratory investigations, electroneuromyography, muscle biopsy with transmission electron microscopy, scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), and, in one case, brain magnetic resonance imaging. They had received regular immunizations. Two patients were hypotonic and one presented with myotonia. Muscle biopsy of all patients presented macrophagic infiltrates with intracytoplasmic aluminum content as revealed by SEM/EDS analysis. Their diverse clinical picture does not support a direct relationship between local morphologic findings and systemic symptoms. The atypical clinical presentation of these children may not result from the superposition of MMF upon a background systemic neuromyopathy, suggesting instead that they are two coincident and independent conditions. Although the finding of macrophage infiltrates in muscle tissue is not new, the identification of aluminum content is recent. The use of tissue sections for aluminum detection and mapping by SEM/EDS is conclusive for, diagnosis; it has not been reported previously in a pathology journal, to the authors' knowledge. 相似文献
145.
Márquez-Caraveo María Elena Ibarra-González Isabel Rodríguez-Valentín Rocío Ramírez-García Miguel Ángel Pérez-Barrón Verónica Lazcano-Ponce Eduardo Vela-Amieva Marcela 《Journal of autism and developmental disorders》2021,51(6):2124-2131
Journal of Autism and Developmental Disorders - The objective of our study was to evaluate the frequency of treatable inborn errors of metabolism (IEM) in a clinical sample of Mexican children and... 相似文献
146.
Cost Katherine T. Zaidman-Zait Anat Mirenda Pat Duku Eric Zwaigenbaum Lonnie Smith Isabel M. Ungar Wendy J. Kerns Connor Bennett Theresa Szatmari Peter Georgiades Stelios Waddell Charlotte Elsabbagh Mayada Vaillancourt Tracy 《Journal of autism and developmental disorders》2021,51(12):4575-4576
Journal of Autism and Developmental Disorders - 相似文献
147.
Jonathan Bryant-Genevier Carol Y. Rao Barbara Lopes-Cardozo Ahoua Kone Charles Rose Isabel Thomas Diana Orquiola Ruth Lynfield Dhara Shah Lori Freeman Scott Becker Amber Williams Deborah W. Gould Hope Tiesman Geremy Lloyd Laura Hill Ramona Byrkit 《MMWR. Morbidity and mortality weekly report》2021,70(26):947
148.
Moreau Anthony Ego Amedee Vandergheynst Frederic Taccone Fabio Silvio Sadeghi Niloufar Montesinos Isabel Gaspard Nicolas Gorham Julie 《Journal of neurology》2021,268(5):1592-1594
Journal of Neurology - 相似文献
149.
Gil-Gouveia Raquel Marques Inês Brás Parreira Elsa Paixão Martins Isabel Pavão Oliveira António Gouveia 《Neurological sciences》2021,42(10):4163-4174
Neurological Sciences - This study aimed to validate a semi-quantitative composite score tool, “Headache Gauge” (HG), to monitor the treatment effect in primary headaches in everyday... 相似文献