Carbonic anhydrase isoforms I and II (hCA-I and hCA-II) are metalloenzymes involved in essential physiological processes and represent relevant therapeutic targets for disorders such as glaucoma and osteoporosis. Chalcones have emerged as promising scaffolds for carbonic anhydrase inhibition; however, their structure-activity relationships, particularly for non-sulfonamide derivatives, remain insufficiently explored from a computational point of view. In this study, a dataset of 118 chalcone derivatives has been analyzed by using a three-dimensional quantitative structure-activity relationship (3D-QSAR) modeling, which comprises Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Index Analysis (CoMSIA). The developed models exhibited strong internal consistency and predictive capability for both isoforms. For hCA-I, steric, electrostatic, hydrophobic, and hydrogen bond acceptor fields has been identified as key contributors to inhibitory activity, whereas for hCA-II, hydrogen bond donor features played a more prominent role. Molecular docking and molecular dynamics simulations have been employed as complementary approaches to analyze ligand-protein interactions and binding stability. In addition, quantum chemical descriptors, derived from density functional theory, that have been integrated with the 3D-QSAR analysis, reveal a consistent correspondence between contour map features and the distribution of frontier molecular orbitals and molecular electrostatic potential. Furthermore, ADME-based pharmacokinetic properties of the proposed compounds have been evaluated to assess their potential drug-likeness. Based on the integrated computational analysis, six new chalcone derivatives, with predicted inhibitory activity in the nanomolar range, are proposed. Overall, this study provides a consistent physicochemical framework for understanding the inhibitory activity of chalcone derivatives and highlights key molecular features that may guide the modulation of activity across hCA-I and hCA-II isoforms.
Postural balance is a foundational component of human motor behavior, yet it remains conceptually ambiguous and methodologically heterogeneous across the clinical, educational, and sport sciences. This narrative review aims to provide an integrative framework that clarifies key concepts (postural control vs. postural balance), synthesizes the main sensorimotor and biomechanical mechanisms underpinning balance, and organizes current assessment approaches and functional implications across populations. Narrative literature synthesis was conducted to integrate evidence covering multisensory integration and sensory reweighting, central neural control (spinal, brainstem, cerebellar, and cortical contributions), neuromuscular and biomechanical strategies (e.g., ankle/hip/stepping), and cognitive influences (e.g., dual-task effects). We further summarize commonly used instrumental outcomes derived from force-platform center-of-pressure metrics and widely adopted clinical and functional balance tests, highlighting their typical applications and limitations across the lifespan including pediatric, general adults, older adults, and athletic populations. This review proposes a closed-loop, systems-based model in which postural balance is conceptualized as an emergent functional outcome arising from distributed postural control processes shaped by task, environmental, and individual constraints. In conclusion, integrating mechanistic understanding with population-specific assessment enhances interpretability and supports more precise, context-sensitive balance evaluation and intervention in both health and performance settings.
Background: Parthenocissus quinquefolia (Virginia creeper), widely distributed and used in Chile, lacks a systematic characterization of its bioactive components. This study synthesizes the evidence on the phytochemical composition and biological activities of P. quinquefolia, with emphasis on metabolites involved in redox regulation and inflammation. Methods: A systematic review was conducted following PRISMA 2020 guidelines. Searches were performed across four electronic databases, including original studies reporting antioxidant and anti-inflammatory effects. Results: Of 665 records identified, 14 studies met the inclusion criteria. Phytochemical analyses revealed phenolic compounds, particularly flavonoids (e.g., catechin, epicatechin, gallocatechin, epigallocatechin, quercetin, rutin, isoquercitrin, myricetin, luteolin, naringin) and stilbenes (e.g., ε-viniferin, miyabenol C). These metabolites exhibit antioxidant activity through ROS scavenging, metal chelation, and Nrf2/ARE activation. Anti-inflammatory effects were attributed to the downregulation of NF-κB, AP-1, and MAPK signaling, inhibition of NLRP3 inflammasome activation, and suppression of COX-2/iNOS expression. Conclusions: P. quinquefolia is a rich source of phenolic metabolites with robust antioxidant and anti-inflammatory mechanisms. The consistency of molecular responses across studies highlights its potential as a promising candidate for phytotherapeutic development targeting oxidative stress and inflammatory pathways.
This study investigates the development of antibacterial polypropylene (PP) composites through the incorporation of thiol-functionalized copper nanoparticles (CuNPs–SH) as active additives. The objective was to evaluate the functional performance of the system, with particular emphasis on verifying copper ion release as the active mechanism and its direct relationship with the antibacterial response of the composite material. CuNPs–SH were synthesized and characterized using ultraviolet–visible spectroscopy, X-ray diffraction, and thermogravimetric analysis, along with ion release studies in aqueous medium. The release results show an initial increase in Cu²⁺ ion concentration followed by stabilization over time, indicating a controlled availability of active species. In addition, thermogravimetric analysis confirms the thermal stability of the additive within the temperature range used for PP processing. Subsequently, CuNPs–SH were incorporated into the PP matrix at 10 wt% through melt compounding. X-ray diffraction analysis indicates that the incorporation of the additive does not alter the crystalline structure of the polymer within the detection limits of the technique. The antibacterial performance of the composite, evaluated against Escherichia coli under ISO 22196, showed an approximate reduction of 40.8%, corresponding to a logarithmic reduction of 0.23. These results demonstrate that thiol-functionalized copper nanoparticles can be used as antibacterial additives in PP, representing a novel strategy for the development of functional polymer composites with controlled antibacterial activity.
Water scarcity in arid and semi-arid regions of Chile is intensifying demand for safe irrigation water sources. This study assesses a modular tertiary treatment train for rural wastewater reuse based on fixed-bed polishing with natural zeolite and activated carbon, followed by UV-C disinfection. Pilot-scale implementation at the La Higuera wastewater treatment plant confirmed robust field performance, reducing TSS by ≈ 70%, BOD5 by ≈ 56%, and fecal coliforms by 99.9%, enabling compliance with Chilean irrigation reuse criteria (NCh 1333; DS 90/2001). Average salinity indicators during monitoring were EC = 1774 μS/cm and TDS = 964 mg/L, suggesting moderate irrigation restrictions and practical suitability mainly for moderately salt-tolerant crops under appropriate management (e.g., leaching and drainage). Because the pilot evaluation covered only ∼3-4 months, long-term performance claims remain preliminary, and seasonal variability and fixed-bed media breakthrough/saturation should be validated through extended multi-season monitoring. Persisting limitations include dissolved solids control and maintaining nitrogen removal during extended operation. Overall, the proposed low-energy, locally adaptable train provides a pragmatic and transferable pathway for decentralized water reuse in arid rural settings, with site-specific adaptation mainly required for influent nitrogen loading/speciation, background salinity/TDS, and local reuse regulations, supporting circular water management aligned with SDG 6 and SDG 12.
