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1.
IEEE Trans Med Imaging ; PP2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557622

RESUMEN

Ophthalmic diseases such as central serous chorioretinopathy (CSC) significantly impair the vision of millions of people globally. Precise segmentation of choroid and macular edema is critical for diagnosing and treating these conditions. However, existing 3D medical image segmentation methods often fall short due to the heterogeneous nature and blurry features of these conditions, compounded by medical image clarity issues and noise interference arising from equipment and environmental limitations. To address these challenges, we propose the Spectrum Analysis Synergy Axial-Spatial Network (SASAN), an approach that innovatively integrates spectrum features using the Fast Fourier Transform (FFT). SASAN incorporates two key modules: the Frequency Integrated Neural Enhancer (FINE), which mitigates noise interference, and the Axial-Spatial Elementum Multiplier (ASEM), which enhances feature extraction. Additionally, we introduce the Self-Adaptive Multi-Aspect Loss (LSM), which balances image regions, distribution, and boundaries, adaptively updating weights during training. We compiled and meticulously annotated the Choroid and Macular Edema OCT Mega Dataset (CMED-18k), currently the world's largest dataset of its kind. Comparative analysis against 13 baselines shows our method surpasses these benchmarks, achieving the highest Dice scores and lowest HD95 in the CMED and OIMHS datasets. Our code is publicly available at https://github.com/IMOP-lab/SASAN-Pytorch.

2.
Molecules ; 27(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36500491

RESUMEN

Traditional wound dressings often cannot treat wounds caused by bacterial infections or other wound types that are insensitive to these wound treatments. Therefore, a biodegradable, bioactive hydrogel wound dressing could be an effective alternative option. The purpose of this study was to develop a hydrogel membrane comprised of sodium alginate, polyvinyl alcohol, acrylic acid, and gallic acid for treating skin wounds. The newly developed membranes were analyzed using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), sol-gel fraction, porosity, mechanical strength, swelling, drug release and data modelling, polymeric network parameters, biodegradation, and antioxidation (DPPH and ABTS) and antimicrobial activity against Gram-positive and negative bacteria. The results revealed that hydrogel membranes were crosslinked successfully and had excellent thermal stability, high drug loading, greater mechanical strength, and exhibited excellent biodegradation. Additionally, the swelling ability and the porosity of the surface facilitated a controlled release of the encapsulated drug (gallic acid), with 70.34% release observed at pH 1.2, 70.10% at pH 5.5 (normal skin pH), and 86.24% at pH 7.4 (wounds pH) in 48 h. The gallic acid-loaded hydrogel membranes showed a greater area of inhibition against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli bacteria as well as demonstrated excellent antioxidant properties. Based on Franz cell analyses, the permeation flux of the drug from optimized formulations through mice skin was 92 (pH 5.5) and 110 (pH 7.4) µg/cm2·h-1. Moreover, hydrogel membranes retained significant amounts of drug in the skin for 24 h, such as 2371 (pH 5.5) and 3300 µg/cm2 (pH 7.4). Acute dermal irritation tests in rats showed that hydrogel membranes were nonirritating. Hydrogel membranes containing gallic acid could be an effective option for improving wound healing and could result in faster wound healing.


Asunto(s)
Hidrogeles , Alcohol Polivinílico , Ratones , Ratas , Animales , Alcohol Polivinílico/química , Hidrogeles/química , Alginatos/farmacología , Ácido Gálico/farmacología , Escherichia coli , Antibacterianos/farmacología , Antibacterianos/química
3.
Gels ; 8(12)2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36547330

RESUMEN

In this study, chitosan (CS) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS)-based hydrogels were formulated by the free radical polymerization technique for the controlled release of gallic acid. Fourier transform infrared spectroscopy (FTIR) confirmed the successful preparation and loading of gallic acid within the hydrogel network. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) confirmed the increased thermal stability of the hydrogels following the crosslinking and polymerization of chitosan and AMPS. In X-ray diffraction analysis (XRD), the crystallinity of the raw materials decreased, indicating strong crosslinking of the reagents and the formation of a new polymeric network of hydrogels. Scanning electron microscopy (SEM) revealed that the hydrogel had a rough, dense, and porous surface, which is consistent with the highly polymerized composition of the hydrogel. After 48 h, the hydrogels exhibited higher swelling at pH 1.2 (swelling ratio of 19.93%) than at pH 7.4 (swelling ratio of 15.65%). The drug release was analyzed using ultraviolet-visible (UV-Vis) spectrophotometer and demonstrated that after 48 h, gallic acid release was maximum at pH 1.2 (85.27%) compared to pH 7.4 (75.19%). The percent porosity (78.36%) and drug loading increased with the increasing concentration of chitosan and AMPS, while a decrease was observed with the increasing concentration of ethylene glycol dimethyl methacrylate (EGDMA). Crosslinking of the hydrogels increased with concentrations of chitosan and EGDMA but decreased with AMPS. In vitro studies demonstrated that the developed hydrogels were biodegradable (8.6% degradation/week) and had antimicrobial (zone of inhibition of 21 and 16 mm against Gram-positive bacteria Escherichia coli and Staphylococcus aureus as well as 13 mm against Gram-negative bacteria Pseudomonas aeruginosa, respectively) and antioxidant (73% DPPH and 70% ABTS) properties. Therefore, the prepared hydrogels could be used as an effective controlled drug delivery system.

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