Publications by authors named "Bartlomiej Kozik"

Itraconazole (ITZ) is an antifungal agent used clinically to treat mycotic infections. However, its therapeutic effects are limited by low solubility in aqueous media. Liposome-based delivery systems (LDS) have been proposed as a delivery mechanism for ITZ to alleviate this problem.

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Polyelectrolyte multilayers (PEMs) have found application in modifying material surfaces to make them adhesive or non-adhesive for animal cells. However, PEMs made of strong polyelectrolytes are not fully recognized in the literature. This study focuses on the interplay between the properties of PEM assembled from strong polyelectrolytes and cell adhesion and motility.

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The enantioselectivity of reactions catalyzed by ethylbenzene dehydrogenase, a molybdenum enzyme that catalyzes the oxygen-independent hydroxylation of many alkylaromatic and alkylheterocyclic compounds to secondary alcohols, was studied by chiral chromatography and theoretical modeling. Chromatographic analyses of 22 substrates revealed that this enzyme exhibits remarkably high reaction enantioselectivity toward (S)-secondary alcohols (18 substrates converted with >99% ee). Theoretical QM:MM modeling was used to elucidate the structure of the catalytically active form of the enzyme and to study the reaction mechanism and factors determining its high degree of enantioselectivity.

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Stressful experiences are often well remembered, an effect that has been explained by beta-adrenergic influences on memory consolidation. Here, we studied the impact of stress induced heart rate (HR) responses on memory consolidation in a post-learning stress paradigm. 206 male and female participants saw 52 happy and angry faces immediately before being exposed to the Cold Pressor Test or a non-stressful control procedure.

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Poly(allylamine hydrochloride) (PAH) has found many applications both in biotechnology and biomedical fields. However, its high toxicity toward various mammalian cells significantly limits its effective usage. This study focuses on improving the biological properties of PAH by its modification to strong polyelectrolytes.

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Photosensitizing properties of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin (p-THPP) functionalized by covalent attachment of one chain of poly(ethylene glycol) (PEG) with a molecular weight of 350, 2000, or 5000 Da (p-THPP-PEG(350), p-THPP-PEG(2000), p-THPP-PEG(5000)) were studied in vitro. Dark and photo cytotoxicity of these photosensitizers delivered in solution or embedded in liposomes were evaluated on two cell lines: a human colorectal carcinoma cell line (HCT 116) and a prostate cancer cell line (DU 145), and compared with these treated with free p-THPP. The attachment of PEG chains results in the pronounced reduction of the dark cytotoxicity of the parent porphyrin.

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Interactions between small organic molecules and lipid or cell membranes are important because of their role in the distribution of biologically active substances inside the membrane and their permeation through the cell membranes. In the current paper, we have explored the effect of the attachment of long hydrocarbon tails on the behavior of small organic molecule inside the lipid membrane. Naphthalene with two decyloxy groups attached at the opposite sites of the ring (2,6-bis(decyloxy)naphthalene, 3) was synthesized and incorporated into phosphatidylcholine (PC) vesicles.

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The Quantitative Structure Retention Relationship (QSRR) modeling techniques are employed for prediction of retention behavior of chiral secondary alkylaromatic and alkylheterocyclic alcohols, derivatives of 1-phenylethanol, separated on Chiracel OB-H column. Genetic algorithms and neural networks are used to obtain models predicting Retention Order Index (ROI) (R(2) - 0.99), selectivity ROI log alpha (R(2) - 0.

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5,10,15,20-Tetrakis(4-hydroxyphenyl)porphyrin was functionalized by covalent attachment of poly(ethylene glycol) (PEG) chains of various molecular weights, 350, 2000, and 5000 Da. The properties of PEG-functionalized tetraarylporphyrins in aqueous solution and their interactions with liposomes have been studied. Electronic absorption spectroscopy, dynamic light scattering, atomic force microscopy, and fluorescence quenching were used to monitor aggregation of porphyrin chromophores and behavior of the attached PEG chains in the aqueous solution.

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