作者: Alves, Izabel Almeida ; Staudt, Keli Jaqueline ; Torres, Bruna Gaelzer Silva ; de Araújo, Bibiana Verlindo ; Oliveira, Calinca Elioterio ; Kowalski, Layza ; Rieper, Ryan Lago Araujo

AIMAssessing the disseminated meningitis caused by Cryptoccocus neoformans in Wistar rats and its impact on antifungal distribution by microdialysis (µD).MATERIALS & METHODSThe yeast presence was investigated in different tissues by histological and microbiological assays, and biochemical parameters such as urea, glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT), creatinine, creatine kinase (CK), creatinine, albumin level, leukocyte counts, and brain vascular permeability (Evans blue test) were evaluated in healthy and infected groups. Levels of fluconazole reached in the animal's brain were determined by µD.RESULTSDifferences in albumin, urea, GPT, and CK between healthy and infected animals were observed in the levels of Evans blue as well as in the brain (0.51 vs 1.50 µg/g_brain). The drugs' distribution in the brain of infected animals was higher than that in the brain of healthy ones (ft = 1.37 vs ft = 0.54).CONCLUSIONThe model validated presents characteristics similar to those observed in patients and can be applied to pharmacokinetic investigations.

2025-04-01·International Journal of Environmental Science and Technology

Effect of carboxylic acids in the decomposition of H2O2 in Fenton processes for the degradation of agrochemicals

作者: Dallago, R. M. ; Mulinari, J. ; Zin, L. E. Fusinato ; Di Luccio, M. ; Oro, C. E. Demaman

Agrochems. have become essential to meet the increasing demand for food and other commodities, but they can contaminate the environment, especially water resources, if not properly managed.Advanced Oxidation Processes (AOP), such as Fenton′s process, are a quick alternative to remove these toxic compounds from water and wastewater.Previous studies suggest that carboxylic acids can promote the Fenton reaction by accelerating the degradation rate of H₂O₂ and the formation of hydroxyl radicals.In this study, formic and acetic acids were applied in a heterogeneous Fenton system to degrade imidacloprid (C₉H₁₀N₅ClO₂), a model agrochem. mol.Activated limonite and steel wool were used as low-cost heterogeneous iron precursors.The activated limonite was produced by reducing limonite′s iron under H₂ flow at 200 and 300 °C.The Fenton process with 300 °C-activated limonite showed a reaction rate approx. 8-fold higher than the test using natural limonite and 2-fold higher than the one with limonite activated at 200 °C.Adding acetic acid to the Fenton process using the 300 °C-activated limonite increased the reaction rate by more than 2-fold.When steel wool was used as the iron precursor, the addition of acetic acid resulted in the complete degradation of imidacloprid within 1 min of reaction.Acetic acid exhibited a higher promoting activity than formic acid, and the degradation rate increased with increasing concentrations of both carboxylic acids.This study indicates that carboxylic acids can serve as Fenton promoters to increase the degradation rate of agrochems., such as imidacloprid, present in water and wastewater.Graphical abstract

2025-03-01·Journal of Sol-Gel Science and Technology

Optimization of Candida antarctica lipase immobilization in xerogels using an ionic liquid additive: enhanced esterification activity and thermal stability

作者: Dallago, Rogerio Marcos ; Mignoni, Marcelo Luis ; Todero, Adriele Sabrina ; Reato, Paloma Truccolo ; de Oliveira Pereira, Fabiana

The immobilization of Candida antarctica lipase B (CALB) within xerogels synthesized through the sol-gel method was investigated, employing the ionic liquid 1-octyl-3-methylimidazolium bromide (C8MI.Br) as an additive to enhance enzymic performance.The optimization of enzyme mass and ionic liquid concentration, using a central composite exptl. design, identified optimal conditions of 0.27 g/mL enzyme and 1.53% ionic liquid, yielding a maximum total esterification activity exceeding 500 U.Structural characterization, including BET surface area anal. and X-ray diffraction, confirmed the formation of a porous, amorphous matrix conducive to enzyme stability and activity.The incorporation of the ionic liquid significantly enhanced the xerogels' thermal and operational stability.Residual esterification activity was maintained at approx. 80% after 100 days under refrigeration, and the xerogels exhibited reusability for up to eight catalytic cycles with residual activity above 50%.Furthermore, thermal stability assessments demonstrated superior resistance of the immobilized enzyme to elevated temperatures compared to its free counterpart.This study underscores the critical role of ionic liquids as additives, facilitating the formation of structurally optimized xerogels while preserving enzyme activity and stability.The findings suggest significant potential for industrial biocatalytic processes, offering a sustainable and efficient approach to enzyme immobilization for applications requiring enhanced catalytic performance and longevity.

100 项与 Regional Integrated University of Upper Uruguai & Missions 相关的药物交易

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100 项与 Regional Integrated University of Upper Uruguai & Missions 相关的转化医学

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