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We investigate, both analytically and numerically, diffusion-controlled drug release from composite spherical formulations consisting of an inner core and an outer shell of different drug diffusion coefficients. Theoretically derived analytical results are based on the exact solution of Fick's second law of diffusion for a composite sphere, while numerical data are obtained using Monte Carlo simulations. In both cases, and for the range of matrix parameter values considered in this work, fractional drug release profiles are described accurately by a stretched exponential function. The release kinetics obtained is quantified through a detailed investigation of the dependence of the two stretched exponential release parameters on the device characteristics, namely the geometrical radii of the inner core and outer shell and the corresponding drug diffusion coefficients. Similar behaviors are revealed by both the theoretical results and the numerical simulations, and approximate analytical expressions are presented for the dependencies.
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http://dx.doi.org/10.1016/j.msec.2014.06.009 | DOI Listing |
Sci Signal
September 2025
Department of Surgery, University of Alabama Birmingham, Birmingham, AL 35233, USA.
Amphetamines are psychostimulants that are commonly used to treat neuropsychiatric disorders and are prone to misuse. The pathogenesis of amphetamine use disorder (AUD) is associated with dysbiosis (an imbalance in the body's microbiome) and bacterially produced short-chain fatty acids (SCFAs), which are implicated in the gut-brain axis. Amphetamine exposure in both rats and humans increases the amount of intestinal , which releases SFCAs.
View Article and Find Full Text PDFPharm Dev Technol
September 2025
School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, wenhua Road 103, Shenyang 110016, PR China.
Nimodipine (NMP), a poorly water-soluble small-molecule agent, demonstrates notable therapeutic limitations in addressing cerebral vasospasm secondary to subarachnoid hemorrhage (SAH). Owing to its inherent physicochemical properties characterized by low oral bioavailability, rapid elimination half-life, and extensive first-pass metabolism, conventional formulations necessitate frequent dosing regimens to sustain therapeutic plasma concentrations. These pharmacological challenges collectively result in suboptimal patient adherence, marked plasma concentration fluctuations, and recurrent vascular irritation.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, Kraków 30-387, Poland.
The multifunctional systems presented here introduce an innovative and deeply thought-out approach to the more effective and safer use of temozolomide (TMZ) in treating glioma. The developed hydrogel-based flakes were designed to address the issues of local GBL therapy, bacterial neuroinfections, and the bleeding control needed during tumor resection. The materials obtained comprise TMZ and vancomycin (VANC) loaded into cyclodextrin/polymeric capsules and embedded into gelatin/hyaluronic acid/chitosan-based hydrogel films cross-linked with genipin.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2025
Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37240.
Major depressive disorder affects millions worldwide, yet current treatments require prolonged administration. In contrast, ketamine produces rapid antidepressant effects by blocking spontaneous N-Methyl-D-Aspartate (NMDA) receptor signaling, which lifts the suppression of protein synthesis and triggers homeostatic synaptic plasticity. Here, we identify a parallel signaling pathway involving metabotropic glutamate receptor 5 (mGluR5) that promotes rapid antidepressant-like effects.
View Article and Find Full Text PDFAcc Chem Res
September 2025
Department of Chemistry, FRQNT Centre for Green Chemistry and Catalysis, McGill University, 801 Sherbrooke Street W, Montréal, Québec H3A 0B8, Canada.
ConspectusMolecular photochemistry, by harnessing the excited states of organic molecules, provides a platform fundamentally distinct from thermochemistry for generating reactive open-shell or spin-active species under mild conditions. Among its diverse applications, the resurgence of the Minisci-type reaction, a transformation historically reliant on thermally initiated radical conditions, has been fueled by modern photochemical strategies with improved efficiency and selectivity. Consequently, the photochemical Minisci-type reaction ranks among the most enabling methods for C()-H functionalizations of heteroarenes, which are of particular significance in medicinal chemistry for the rapid diversification of bioactive scaffolds.
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