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Katedra Chemii Fizycznej
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wszystkich: 372
Katalog Publikacji
Rok 2012
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A coordination chemistry study of hydrated and solvated cationic vanadium ions in oxidation states +III, +IV, and +V in solution and solid state
PublikacjaPrzedmiotem studiów jest chemia koordynacyjna solwatów jonów wanadu(III), oksowanadu(IV) jaki i dioksowanadu(V) w rozpuszczalnikach tlenowo-donorowych takich jak: woda, dimetylosulfotlenek (DMSO) oraz N,N'-dimetylopropylenomocznik (DMPU). Badania prowadzone były w roztworach ciekłych jak i w fazie stałej z wykorzystaniem absorpcji (EXAFS), rozproszenia (LAXS) jak i dyfrakcji promieniowania X. Analiza uzyskanych wyników wskazuje,...
Rok 2014
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A first-principles study of electron attachment to the fully hydrated bromonucleobases
PublikacjaDegradation mechanism of four brominated nucleobases (BrX), potential DNA radiosensitizers, is studied in explicit water solution, using ab initio molecular dynamics. Several fs long dynamics is needed to localize an electron on the nucleobase. Produced by electron attachment BrX anion radical degrades through the bromide anion abstraction, barrier-free (purines) or with low barrier (pyrimidines), to a reactive nucleobase radical....
Rok 2022
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A Novel Cryptic Clostridial Peptide That Kills Bacteria by a Cell Membrane Permeabilization Mechanism
PublikacjaThis work reports detailed characteristics of the antimicrobial peptide Intestinalin (P30), which is derived from the LysC enzyme of Clostridium intestinale strain URNW. The peptide shows a broader antibacterial spectrum than the parental enzyme, showing potent antimicrobial activity against clinical strains of Gram-positive staphylococci and Gram-negative pathogens and causing between 3.04 ± 0.12 log kill for Pseudomonas aeruginosa...
Rok 2020
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A rapid dispersive liquid–liquid microextraction of antimicrobial onion organosulfur compounds in animal feed coupled to gas chromatography-mass spectrometry
PublikacjaA rapid analytical procedure is proposed for determining two antimicrobial onion organosulfur compounds, propyl disulfide (PDS) and propyl propane thiosulfonate (PTSO), in animal feed. The use of PTSO as a natural ingredient in animal feed is allowed due to its antimicrobial activity against pathogenic organisms. Two analytical methodologies using gas chromatography coupled to mass spectrometry (GC-MS) are compared. After the extraction...
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A shear stress micromodel of urinary tract infection by the Escherichia coli producing Dr adhesin
PublikacjaIn this study, we established a dynamic micromodel of urinary tract infection to analyze the impact of UT-segment-specific urinary outflow on the persistence of E. coli colonization. We found that the adherence of Dr+ E. coli to bladder T24 transitional cells and type IV collagen is maximal at lowest shear stress and is reduced by any increase in flow velocity. The analyzed adherence was effective in the whole spectrum of physiological...
Rok 2019
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A Three-Step Approach to Estimation of Reduction Potentials of Natural Mixtures of Antioxidants Based on DPPH Test; Illustration for Catechins and Cocoa
PublikacjaThe aim of this study is to propose a methodology to assess electrochemical properties of complex mixtures of antioxidants, such as plant extracts, based on the results of simple and popular DPPH test. The first, most difficult step, involves determinations of standard reduction potentials (E0) for the series of purified compounds (here catechins). The next step is the calculation of stoichiometric values (n10) based on the results...
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Amides as models to study the hydration of proteins and peptides — spectroscopic and theoretical approach on hydration in various temperatures
PublikacjaInteractions with water are one of the key factors which determine protein stability and activity in aqueous solutions. However, the protein hydration is still insufficiently understood. N-methylacetamide (NMA) is regarded as a minimal part of the peptide backbone and the relative simplicity of its structure makes it a good model for studies on protein–water interactions. In this paper, the influence of NMA and N,N-dimethylacetamide...
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Amyloid fibril formation in the presence of water structure-affecting solutes
PublikacjaThe impact of the differently hydrated non-electrolytes (protein structure destabilizers) on the fibrillation of hen egg white lysozyme (HEWL) was investigated. Two isomeric urea derivatives i.e. butylurea (BU) and N,N,N′,N′-tetramethylurea (TMU) were chosen as a tested compounds. The obtained results show that butylurea exerts greater impact on HEWL and its fibrillation than tetramethylurea. Both substances decrease the time of...
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Analytical applications and physicochemical properties of ionic liquid-based hybrid materials: A review
PublikacjaIonic liquids with their unique properties found so far numerous analytical applications. Among them ionic liquids immobilized on the surface or within the pores of a solid support were successfully utilized in extraction techniques dedicated to preconcentration of the analytes from food, environmental and biological samples. In this review we focus on comprehensive summarizing of available literature data on the examples of ionic...
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ANTIOXIDANT POWER SERIES (APS) AS A TOOL FOR RATIONAL DESIGN AND ASSESSMENT OF HEALTH PROMOTING PROPERTIES OF FUNCTONAL FOODS BASED ON ANTIOXIDANT PHYTOCHEMICALS
PublikacjaOver past decades, plantborne antioxidants dominated so called "translational research" in the area of food, nutrition, and disease prevention. Among consumers and producers, such phytochemicals are synonyms of nutriceuticals. Popularity and commercial success of antioxidants stems from mechanistic studies suggesting the involvement of reactive oxygen species in etiology of chronic diseases. However, epidemiology failed to provide...
Rok 2023
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Ab initio chemical kinetics of Isopropyl acetate oxidation with OH radicals
PublikacjaGlobal reactivity descriptors of isopropyl acetate (IPA) and thermo-kinetic aspects of its oxidation via OH radicals have been studied. Transition state theory (TST) was utilized to estimate the bimolecular rate constants. Ten oxidation pathways have been investigated, and all of them are exothermic. The potential energy diagram has been sketched using different pre- and post-reactive complexes for all reaction pathways. Rate coefficient...
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Analysis of Reconstituted Tripartite Complex Supports Avidity-based Recruitment of Hsp70 by Substrate Bound J-domain Protein
PublikacjaHsp70 are ubiquitous, versatile molecular chaperones that cyclically interact with substrate protein(s). The initial step requires synergistic interaction of a substrate and a J-domain protein (JDP) cochaperone, via its J-domain, with Hsp70 to stimulate hydrolysis of its bound ATP. This hydrolysis drives conformational changes in Hsp70 that stabilize substrate binding. However, because of the transient nature of substrate and JDP...
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Antibiotic-sterol interactions provide insight into the selectivity of natural aromatic analogues of amphotericin B and their photoisomers
PublikacjaAromatic heptaene macrolides (AHMs) belong to the group of polyene macrolide antifungal antibiotics. Members of this group were the first to be used in the treatment of systemic fungal infections. Amphotericin B (AmB), a non-aromatic representative of heptaene macrolides, is of significant clinical importance in the treatment of internal mycoses. It includes the all-trans heptaene chromophore, whereas the native AHMs contain two...
Rok 2021
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Accuracy of Pretreatment Ultrasonography Assessment of Intra-Abdominal Spread in Epithelial Ovarian Cancer: A Prospective Study
PublikacjaThe aim of this study was to test the accuracy of ultrasonography performed by gynecological oncologists for the preoperative assessment of epithelial ovarian cancer (EOC) spread in the pelvis and abdominal cavity. A prospective, observational cohort study was performed at a single tertiary cancer care unit. Patients with suspected EOC were recruited and underwent comprehensive transvaginal and abdominal ultrasonography performed...
Rok 2009
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Adiabatic Compressibilities of Divalent Transition-Metal Perchlorates and Chlorides in N,N-Dimethylacetamide and Dimethylsulfoxide
PublikacjaZmierzono prędkości rozchodzenia się dźwięku roztworów nadchloranów i chlorków manganu(II), kobaltu(II), niklu(II), miedzi(II) i cynku(II) w N,N-dimetyloacetamidzie i dimetylosulfotlenku w temperaturze 298.15 K. Obliczono ściśliwości adiabatyczne i pozorne ściśliwości adiabatyczne badanych roztworów. Przedyskutowano wpływ anionu i rodzaju rozpuszczalnika na uzyskane graniczne wartości pozornych ściśliwości adiabatycznych soli.
Rok 2010
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An effective method for studying intermolecular interactions in binary liquids with hydrogen bonds: FTIR spectra and ab initio calculations in the N-methylformamide - methanol system
PublikacjaMolecular complexes in methanol (MeOH)−N-methylformamide (NMF) mixtures were studied based on their FTIR-ATR spectra, to which two methods of analysis were applied: factor analysis and a quantitative version of the difference-spectra method. The mean composition of a complex between NMF and MeOH molecules over the whole range of mixture compositions was determined. Absorbing species differentiated with regard to the interaction...
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Apparent molar volume and compressinility of tetrabutylphosphonium bromide in various solvents
PublikacjaW oparciu o pomiary gęstości wyznaczono pozorne objętości molowe bromku czero-n-butylofosfoniowego w etanolu, 1-propanolu, 1-butanolu, acetonie i acetonitrylu w przedziale temperatur od 288,15 K do 323,15 K. Ponadto zmierzone w 298,15 K szybkości rozchodzenia się dźwięku w badanych cieczach pozwoliły obliczyć pozorne ściśliwości adiabatyczne bromku. Wielkości pozorne ekstrapolowano do nieskończenie rozcieńczonego stężenia w celu...
Rok 2011
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Analysis of the unique structural and physicochemical properties of the DraD/AfaD invasin in the context of its belonging to the family of chaperone/usher type fimbrial subunits
PublikacjaInwazyna DraD kodowana przez operon dra posiada strukturę charakterystyczną dla białek podjednostkowych fimbrii typu chaperone-usher. Fold-Ig białka DraD posiada dwie charakterystyczne cechy wyróżniające je z pośród rodziny fimbrialnych białek podjednostkowych: 1) zaburzenie struktury beta-beczki w rejonie szczeliny akceptorowej objawiające się układem wiązań wodorowych głównego łańcucha polipeptydowego oraz 2) nietypowo usytuowany...
Rok 2016
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Anion–water interactions of weakly hydrated anions: molecular dynamics simulations of aqueous NaBF4 and NaPF6
PublikacjaIn aqueous ionic solutions, both the structure and the dynamics of water are altered dramatically with respect to the pure solvent. The emergence of novel experimental techniques makes these changes accessible to detailed investigations. At the same time, computational studies deliver unique possibilities for the interpretation of the experimental data at the molecular level. Here, using molecular dynamics simulations, we demonstrate...
Rok 2007
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Apparent molar compressibilities and volumes of some 1,1-electrolytes in N,N-dimethylacetamide and N,N-dimethylformamide
PublikacjaZmierzono gęstości roztworów tetrafenyloboranu sodu, bromku tetrafenylofosfoniowego, bromku sodu i nadchloranu sodu w N, N-dimetyloacetamidzie i N,N-dimetyloformamidzie w zakresie stężeń (0.015 to 0.40) mol·kg-1 w zakresie temperatur od 283.15 K do 333.15 K. Z uzyskanych danych obliczono pozorne i cząstkowe objętości molowe jak również rozszerzalności temperaturowe. Dodatkowo, wartości prędkości rozchodzenia się dźwięku...