Browsing by Author "Vivar, Raul"

Now showing 1 - 3 of 3
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    Changes in the pattern of fibrosis in the rat lung with repetitive orotracheal instillations of gastric contents: evidence of persistent collagen accumulation
    (2018) Ayala, Pedro; Torres, Jorge; Vivar, Raul; Olmos Coelho, Pablo Roberto; Meneses, Manuel; Borzone, Gisella
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    Lipopolysaccharide Activates Toll-Like Receptor 4 and Prevents Cardiac Fibroblast-to-Myofibroblast Differentiation
    (HUMANA PRESS INC, 2017) Bolivar, Samir; Santana, Roxana; Ayala, Pedro; Landaeta, Rodolfo; Boza, Pia; Humeres, Claudio; Vivar, Raul; Munoz, Claudia; Pardo, Viviana; Fernandez, Samuel; Anfossi, Renatto; Diaz Araya, Guillermo
    Bacterial lipopolysaccharide (LPS) is a known ligand of Toll-like receptor 4 (TLR4) which is expressed in cardiac fibroblasts (CF). Differentiation of CF to cardiac myofibroblasts (CMF) is induced by transforming growth factor-beta 1 (TGF-beta 1), increasing alpha-smooth muscle actin (alpha-SMA) expression. In endothelial cells, an antagonist effect between LPS-induced signaling and canonical TGF-beta 1 signaling was described; however, it has not been studied whether in CF and CMF the expression of alpha-SMA induced by TGF-beta 1 is antagonized by LPS and the mechanism involved. In adult rat CF and CMF, alpha-SMA, ERK1/2, Akt, NF-kappa beta, Smad3, and Smad7 protein levels were determined by western blot, TGF-beta isoforms by ELISA, and alpha-SMA stress fibers by immunocytochemistry. CF and CMF secrete the three TGF-beta isoforms, and the secretion levels of TGF-beta 2 was affected by LPS treatment. In CF, LPS treatment decreased the protein levels of alpha-SMA, and this effect was prevented by TAK-242 (TLR4 inhibitor) and LY294002 (Akt inhibitor), but not by BAY 11-7082 (NF-kappa beta inhibitor) and PD98059 (ERK1/2 inhibitor). TGF-beta 1 increased alpha-SMA protein levels in CF, and LPS prevented partially this effect. In addition, in CMF alpha-SMA protein levels were decreased by LPS treatment, which was abolished by TAK-242. Finally, in CF LPS decreased the p-Smad3 phosphorylation and increased the Smad7 protein levels. LPS treatment prevents the CF-to-CMF differentiation and reverses the CMF phenotype induced by TGF-beta 1, through decreasing p-Smad3 and increasing Smad7 protein levels.
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    Moxifloxacin vs amoxicillin/clavulanate in the treatment of acute sinusitis
    (W B SAUNDERS CO-ELSEVIER INC, 2007) Arrieta, Jose R.; Galgano, Alejandro S.; Sakano, Eulalia; Fonseca, Ximena; Amabile Cuevas, Carlos F.; Hernandez Oliva, Gerardo; Vivar, Raul; Gonzalez, Gerardo; Torres, Arturo; MASS Latin Am Study Grp
    Purpose: The aim of this study was to compare the efficacy and safety of moxifloxacin with that of amoxicillin/clavulanate for the treatment of acute bacterial sinusitis in adults.