Browsing by Author "Zuniga, C."

Now showing 1 - 4 of 4
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    Design and operational implementation of the integrated tsunami forecast and warning system in Chile (SIPAT)
    (2020) Catalan, P. A.; Gubler, A.; Canas, J.; Zuniga, C.; Zelaya, C.; Pizarro, L.; Valdes, C.; Mena, R.; Toledo, E.; Cienfuegos Carrasco, Rodrigo Alberto
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    Therapeutic Drug Monitoring of Mycophenolic Acid in Kidney Transplant Patients: A Abbreviated Sampling Strategy
    (2007) Muller, H.; Solari Gajardo, Sandra; Zuniga, C.; Guerra Venegas, Irene Del Carmen; Troncoso, J.; Ovalle, R.; Morente, J.; Pedreros, C.
    Mycophenolic acid (MPA) levels have demonstrated a good correlation with clinical outcomes, but with great pharmacokinetic variability between patients. Therapeutic drug monitoring (TDM) is recommended to include a 12-hour area under the concentration–time curve (AUC). Since full AUC estimates are not practical for routine monitoring, limited sampling strategies have been suggested. We evaluated MPA pharmacokinetics in 18 stable renal transplant patients receiving mycophenolate mofetil (MMF) as part of their immunosuppressive therapy. The correlation between measured and estimated AUC was assessed using 4 different sparse sampling algorithms. The mean values for C0 and AUC0–6h were 1.8 ± 1.2 mg/L and 31.1 ± 14.8 mg*h/L, respectively. The dose-corrected AUC0–6h was 35.4 ± 17.9 mg*h/L. Regarding the single time points, C0 showed a low correlation with AUC0–6h (r2 = .34); C1.5, the best correlation (r2 = .72); and C3, the worst (r2 = .07). Sparse sample algorithms used to estimate 12-hour AUC including C0, C1, C2, C3, C4, and/or C6 showed a good correlation with the calculated AUC0–6 (r2 = .81–.96). The algorithm that used C0, C1, C2, and C4 showed the best correlation, but we also found a good correlation (r2 = .91) with C0, C1, and C2. Based on these results, we have suggested using the 3-point algorithm (C0, C1, and C2) for MPA TDM in stable renal transplant patients due to the good correlation with drug exposure and better functionality than an algorithm using a 4-hour postdose measurement.
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    Using Telenephrology to Improve Access to Nephrologist and Global Kidney Management of CKD Primary Care Patients
    (2020) Zuniga, C.; Riquelme Pizarro, Carlos Rodrigo; Muller, H.; Vergara, G.; Astorga, C.; Espinoza Sepúlveda, Manuel Antonio
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    β-cyclodextrin and adamantane polyacrylic acid copolymers as supramolecular binder for silicon anodes: N-methylpyrrolidone or water for preparing the slurries?
    (2024) Ortiz, M. G.; Sanservino, M. A.; Visintin, A.; Pizarro, G. del C.; Tundidor-Camba, M. V.; Schott, E.; Sepulveda, A.; Zuniga, C.; Oyarzun, D. P.; Martin-Trasancos, R.
    Silicon is a promising material for anodes in future generations of LIBs. However, its volume changes during the lithiation/delithiation process that degrades battery performance, making it an impractical alternative. To mitigate this issue, we have found a viable alternate solution, which is the preparation of adamantane-polyacrylic acid (AdEN-AA) and beta-cyclodextrin-polyacrylic acid (beta CD6A-AA) polymers as supramolecular binders. The advantage of these binders is that polymers leverage host-guest interactions. To carry out this research, we prepared the anode materials in water and in NMP, and then we studied their capacity to crosslink and gel. Additionally, we examined the extent of the supramolecular interaction vs. hydrogen bond. Thermogravimetric analysis showed that the thermal stability of the mixture of complementary polymer increased in the following order: AdEN-AA/beta CD6A-AA in NMP < beta CD6A-AA/PAA < AdEN-AA/beta CD6A-AA, with the latter two in water. Accordingly, the anode material prepared in water shows the highest stability, retaining capacities of over 1000 mAhg(-1) after 90 cycles vs. 279 mAhg-1 of the electrode prepared in NMP. The results agreed with the SEM micrographs of the anode material, in which the slurry prepared in water showed better integrity of the silicon nanoparticles and of solid electrolyte interphase than the slurry prepared in NMP.