Browsing by Author "Sandoval, Mauricio"

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    Addition of Chitosan May Improve the Treatment Efficacy of Triple Bandage and Compression in the Treatment of Venous Leg Ulcers
    (JOURNAL OF DRUGS IN DERMATOLOGY, 2011) Sandoval, Mauricio; Albornoz, Claudia; Munoz, Sonia; Fica, Mirta; Garcia Huidobro, Isidora; Mertens, Renato; Hasson, Ariel
    Introduction Venous leg ulcers are an important problem in public health due to their high prevalence and treatment cost The gold standard therapy is the compression bandage Addition of different substances to the compression therapy in order to accelerate ulcer healing has been attempted but none of them has yielded optimal results
  • No Thumbnail Available
    Item
    Antagonistic effects of TrkB and p75NTR on NMDA receptor currents in post-synaptic densities transplanted into Xenopus oocytes
    (2007) Sandoval, Mauricio; Sandoval, Rodrigo; Thomas, Ulrich; Spilker, Christina; Smalla, Karl-Heinz; Falcon, Romina; Marengo, Juan Jose; Calderon, Rodrigo; Saavedra, Veronica; Heumann, Rolf; Bronfman, Francisca; Garner, Craig C.; Gundelfinger, Eckart D.; Wyneken, Ursula
    Brain-derived neurotrophic factor (BDNF) and its receptor TrkB are essential regulators of synaptic function in the adult CNS. A TrkB-mediated effect at excitatory synapses is enhancement of NMDA receptor (NMDA-R)-mediated currents. Recently, opposing effects of TrkB and the pan-neurotrophin receptor p75(NTR) on long-term synaptic depression and long-term potentiation have been reported in the hippocampus. To further study the regulation of NMDA-Rs by neurotrophin receptors in their native protein environment, we micro-transplanted rat forebrain post-synaptic densities (PSDs) into Xenopus oocytes. One-minute incubations of oocytes with BDNF led to dual effects on NMDA-R currents: either TrkB-dependent potentiation or TrkB-independent inhibition were observed. Pro-nerve growth factor, a ligand for p75(NTR) but not for TrkB, produced a reversible, dose-dependent, TrkB-independent and p75(NTR)-dependent inhibition of NMDA-Rs. Fractionation experiments showed that p75(NTR) is highly enriched in the PSD protein fraction. Immunoprecipitation and pull-down experiments further revealed that p75(NTR) is a core component of the PSD, where it interacts with the PDZ3 domain of the scaffolding protein SAP90/PSD-95. Our data provide striking evidence for a rapid inhibitory effect of p75(NTR) on NMDA-R currents that antagonizes TrkB-mediated NMDA-R potentiation. These opposing mechanisms might be present in a large proportion of forebrain synapses and may contribute importantly to synaptic plasticity.
  • No Thumbnail Available
    Item
    Lidocaine use in localized thin fiber neuropathy associated with lichen simplex chronicus
    (2023) Sandoval, Mauricio; Curi, Maximiliano; Solis-Avaca, Marco; Espinoza, Fernanda; Almeida, Paula; Calvo, Margarita
    Lichen simplex chronicus (LSC) is a common condition whose pathophysiology is partially known. The sensory innervation of the skin consists of a dermal plexus made up of myelinated and unmyelinated fibers. The epidermis only contains unmyelinated fibers, which indicate temperature, pain, and/or itching. Until now, the presence of small-fiber neuropathy in LSC had not been studied and its role in this disease was not known. Therefore, there was no documented therapy to treat this disease with the knowledge of its presence in it. A cohort of 33 patients with LSC who underwent study for the presence of fine fiber neuropathy and alteration in its function is presented.According to the results, a concept test of a novel therapy with lidocaine patches was carried out, proving to be effective.
  • Thumbnail Image
    Item
    Linear IgA bullous dermatosis: report of five cases in Chile
    (WILEY, 2012) Sandoval, Mauricio; Magdalena Farias, Maria; Gonzalez, Sergio
    Background Linear IgA bullous dermatosis (LABD) is an acquired autoimmune sub-epidermal vesiculobullous disease characterized by continuous linear IgA deposit on the basement membrane zone, as visualized on direct immunofluorescence microscopy. LABD can affect both adults and children. The disease is very uncommon, with a still unknown incidence in the South American population. Materials and methods All confirmed cases of LABD by histological and immunofluorescence in our hospital were studied. Results The confirmed cases were three females and two males, aged from 8 to 87 years. Precipitant events associated with LABD were drug consumption (non-steroid inflammatory agents in two cases) and ulcerative colitis (one case). Most of our patients were treated with dapsone, resulting in remission. Discussion Our series confirms the heterogeneous clinical features of this uncommon disease in concordance with a larger series of patients reported in the literature.
  • Thumbnail Image
    Item
    Postirradiation Pseudosclerodermatous Panniculitis of the Leg : Report of a Case and Review of the Literature
    (2015) Sandoval, Mauricio; Giesen, Laura; Cataldo Cerda, Karina; González Bombardiere, Sergio