1. Cytotoxicity and antibacterial efficacy of betaine- and choline-substituted polymersLucija Jurko, Damjan Makuc, Alja Štern, Janez Plavec, Bojana Žegura, Perica Bošković, Rupert Kargl, 2023, izvirni znanstveni članek Povzetek: Cationic charge has been widely used to increase polymer adsorption and flocculation of dispersions or to provide antimicrobial activity. In this work, cationization of hydroxyethyl cellulose (HEC) and polyvinyl alcohol (PVA) was achieved by covalently coupling betaine hydrochloride and choline chloride to the polymer backbones through carbonyl diimidazole (CDI) activation. Two approaches for activation were investigated. CDI in excess was used to activate the polymers’ hydroxyls followed by carbonate formation with choline chloride, or CDI was used to activate betaine hydrochloride, followed by ester formation with the polymers’ hydroxyls. The first approach led to a more significant cross-linking of PVA, but not of HEC, and the second approach successfully formed ester bonds. Cationic, nitrogen-bearing materials with varying degrees of substitution were obtained in moderate to high yields. These materials were analyzed by Fourier transform infrared spectroscopy, nuclear magnetic resonance, polyelectrolyte titration, and kaolin flocculation. Their dose-dependent effect on the growth of Staphylococcus aureus and Pseudomonas aeruginosa, and L929 mouse fibroblasts, was investigated. Significant differences were found between the choline- and betaine-containing polymers, and especially, the choline carbonate esters of HEC strongly inhibited the growth of S. aureus in vitro but were also cytotoxic to fibroblasts. Fibroblast cytotoxicity was also observed for betaine esters of PVA but not for those of HEC. The materials could potentially be used as antimicrobial agents for instance by coating surfaces, but more investigations into the interaction between cells and polysaccharides are necessary to clarify why and how bacterial and human cells are inhibited or killed by these derivatives, especially those containing choline.
Ključne besede: hydroxyethyl cellulose, polyvinyl alcohol, antimicrobial, S. aureus, P. aeruginosa, L929 mouse fibroblast, cationic polymer
Objavljeno v DiRROS: 12.07.2024; Ogledov: 18; Prenosov: 5
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2. Disordered eating attitudes, depressive symptomatology and alcohol consumption in young athletesUroš Perko, Maša Černelič Bizjak, 2022, izvirni znanstveni članek Povzetek: Purpose: The aim of the study was to investigate the prevalence of disordered ea-ting behaviours and attitudes in Slovenian male and female categorized athletes in relation to depressive symptoms and their alcohol consumption. Methods: The sample included 198 categorized athletes between 18 and 20 years of age. The Eating Attitude Test, the Center for Epidemiologic Studies Depression Scale, and the Alcohol Use Disorders Identification Test were used to measure disordered eating behaviours, level of depression, and alcohol use, respectively.Results: Significant differences were found between female and male at-hletes, with female athletes reporting higher levels of disordered eating atti-tudes and depressive symptoms. 13.90% of athletes reported clinically signi-ficant eating disorder symptoms, 40% reported clinically significant depres-sive symptoms, and 10.50% reported risky alcohol use.Results also showed that athletes with higher eating disorder attitudes had higher depressive levels.Conclusion: These findings have important practical value and point to the importance of building a professional team trained to recognize mental health problems in athletes in order to provide appropriate help.
Ključne besede: disordered eating behaviours, athletes, depression, alcohol consumption
Objavljeno v DiRROS: 15.04.2024; Ogledov: 252; Prenosov: 152
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4. Potential effect of UV radiation on the optical and anti-microbial properties of PVA/metal-saltnanocompositesHuda Alkhaldi, Zinab Alshor, Waheedh Albarqi, Manal Alzahrani, Mohamed Madani, 2022, izvirni znanstveni članek Ključne besede: polyvinyl alcohol, UV-irradiation, optical, dielectric relaxation, anti-microbial
Objavljeno v DiRROS: 22.06.2022; Ogledov: 541; Prenosov: 259
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