Browsing by Author "Fadic, Ricardo"

Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    Economic benefits of treating medication-overuse headache - results from the multicenter COMOESTAS project
    (2019) Jellestad, Pernille Linde; Carlsen, Louise Ninett; Westergaard, Maria Lurenda; Munksgaard, Signe Bruun; Bendtsen, Lars; Lainez, Miguel; Fadic, Ricardo; Katsarava, Zaza; Teresa Goicochea, Maria; Spadafora, Santiago; Jensen, Rigmor Hojland; Nappi, Giuseppe; Tassorelli, Cristina; Sances, Grazia; Allena, Marta; Rapsch, Marina; Lopez, Beatriz; Shand, Beatriz
    Background Medication-overuse headache is a costly disease for individuals and society.
  • No Thumbnail Available
    Item
    Increase in decorin and biglycan in Duchenne Muscular Dystrophy: role of fibroblasts as cell source of these proteoglycans in the disease
    (2006) Fadic, Ricardo; Mezzano, Valeria; Alvarez, Karin; Cabrera, Daniel; Holmgren, Jenny; Brandan, Enrique
    Fibrosis is a common pathological feature observed in muscles of patients with. Duchenne muscular dystrophy (DMD). Biglycan and decorin are small chondroitin/dermatan sulfate proteoglycans in the muscle extracellular matrix (ECM) that belong to the family of structurally related proteoglycans called small leucine-rich repeat proteins. Decorin is considered an anti-fibrotic agent, preventing the process by blocking TGF-beta activity. There is no information about their expression in DMD patients. We found an increased amount of both proteoglycans in the ECM of skeletal muscle biopsies obtained from DMD patients. Both biglycan and decorin were augmented in the perimysium of muscle tissue, but only decorin increased in the endomysium as seen by immunohistochemical analyses. Fibroblasts were isolated from explants obtained from muscle of DMD patients and the incorporation of radioactive sulfate showed an increased synthesis of both decorin and biglycan in cultured fibroblasts compared to controls. The size of decorin and biglycan synthesized by DMD and control fibroblasts seems to be similar in size and anion charge. These findings show that decorin and biglycan are increased in DMD skeletal muscle and suggest that fibroblasts would be, at least, one source for these proteoglycans likely playing a role in the muscle response to dystrophic cell damage.
  • No Thumbnail Available
    Item
    Intracellular amyloid formation in muscle cells of Aβ-transgenic Caenorhabditis elegans: determinants and physiological role in copper detoxification
    (2009) Minniti, Alicia N.; Rebolledo, Daniela L.; Grez, Paula M.; Fadic, Ricardo; Aldunate, Rebeca; Volitakis, Irene; Cherny, Robert A.; Opazo, Carlos; Masters, Colin; Bush, Ashley I.; Inestrosa, Nibaldo C.
    Background: The amyloid beta-peptide is a ubiquitous peptide, which is prone to aggregate forming soluble toxic oligomers and insoluble less-toxic aggregates. The intrinsic and external/environmental factors that determine A beta aggregation in vivo are poorly understood, as well as the cellular meaning of this process itself. Genetic data as well as cell biological and biochemical evidence strongly support the hypothesis that A beta is a major player in the onset and development of Alzheimer's disease. In addition, it is also known that A beta is involved in Inclusion Body Myositis, a common myopathy of the elderly in which the peptide accumulates intracellularly.
  • No Thumbnail Available
    Item
    Sympathetic and electrochemical skin responses in the assessment of sudomotor function: a comparative study
    (2023) Idiaquez, Juan; Casar, Juan Carlos; Fadic, Ricardo; Iturriaga, Rodrigo
    Objectives: The sympathetic skin response (SSR) is a well-established test, whereas the electro-chemical skin conductance (ESC) is still under evaluation. Our aim was therefore to assess the diagnostic accuracy of ESC to detect abnormal sudomotor function, using SSR as a reference test.Methods: A cross sectional observational study was performed of 61 neurological patients assessed for possible sudomotor dysfunction and 50 age-matched healthy controls (HC). Patients with diagnoses of vasovagal syncope (VVS, n=25), Parkinson's disease (PD, n=15), multiple system atrophy (MSA, n=11) and peripheral neuropathies (PN, n=10) were included. Sudomotor function was assessed with SSR and ESC tests in all participants. The absence of SSR in the palms or soles indicates abnormal sudomotor function. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic value of the ESC. Cardiovascular autonomic (CV-Aut) function was evaluated through the Ewing score, based on the following tests: Heart rate change with deep breathing, Valsalva ratio, 30:15 ratio, blood pressure changes on standing and during isometric exercise. A Ewing score > 2 indicates the presence of CV-Aut dysfunction.Results: Mean SSR amplitudes and ESC values showed differences between HC and patients with MSA or PN (p < 0.05), but not in patients with VVS or PD. Absence of SSR was associated with abnormal ESC (p < 0.05). Patients with abnormal CV-Aut dysfunction had lower ESC (p< 0.05). Palm ESC (P-ESC) and sole ESC (S-ESC) assessment had a sensitivity of 0.91 and 0.95 to predict sudomotor dysfunction, with a specificity of 0.78 and 0.85, respectively. The area under ROC curve was 0.905 and 0.98, respectively.Conclusions: ESC in palms and soles has a high diagnostic accuracy for sudomotor dysfunction as detected by absent SSR in patients with MSA and PN. (c) 2022 Elsevier Masson SAS. All rights reserved.
  • No Thumbnail Available
    Item
    Transient orthostatic hypertension after partial cerebellar resection
    (2011) Idiaquez, Juan; Fadic, Ricardo; Mathias, Christopher J.
    An effective baroreflex and autonomic pathways normally ensure that blood pressure (BP) is satisfactorily maintained, despite various stimuli in daily life that include postural changes. We describe a 20-year-old man with a cerebellar hematoma and acute hydrocephalus, who had a vermian and partial right cerebellar hemisphere resection followed by orthostatic hypertension (OHT) and mutism. On standing his systolic BP rose over 60 mmHg with a fivefold increase in plasma noradrenaline. After a period of 8 weeks, postural BP regulation improved along with his ability to communicate. We conclude that transient impairment of cerebellar autonomic modulation or dysfunction of the baroreflex medullary circuit, may have resulted in OHT.