Publications by authors named "Kowalska P"

Article Synopsis
  • Violacein is a purple pigment from bacteria that shows a lot of promise due to its biological properties, but it's not very water-soluble, making it tricky to study.
  • This study investigates how Janthinobacterium lividum uses extracellular vesicles (EVs) to transport violacein, finding that these EVs were more effective in producing and delivering the compound than traditional methods.
  • The research suggests that J. lividum EVs can successfully deliver violacein to human cells, specifically targeting melanoma, which opens up new possibilities for cancer treatment.
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One of the promising candidates for new antimicrobial agents is membrane-lytic compounds that kill microbes through cell membrane permeabilization, such as antimicrobial peptides (AMPs) and their synthetic mimics (SMAMPs). Although SMAMPs have been under investigation for nearly 30 years, a few challenges must be addressed before they can reach clinical use. In this work, a step-growth polymerization leading to already-known highly antimicrobial ionenes was redirected toward the formation of macrocyclic quaternary ammonium salts (MQAs) employing a high dilution principle.

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Extracellular vesicles (EVs) are nanoparticles containing various bioactive cargos-e.g., proteins, RNAs, and lipids-that are released into the environment by all cell types.

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Melanoma is a life-threatening disease due to the early onset of metastasis and frequent resistance to the applied treatment. For now, no single histological, immunohistochemical or serological biomarker was able to provide a precise predictive value for the aggressive behavior in melanoma patients. Thus, the search for quantifying methods allowing a simultaneous diagnosis and prognosis of melanoma patients is highly desirable.

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The development of an effective method of melanocyte isolation and culture is necessary for basic and clinical studies concerning skin diseases, including skin pigmentation disorders and melanoma. In this paper, we describe a novel, non-enzymatic and effective method of skin melanocyte and metastatic melanoma cell isolation and culture (along with the spontaneous spheroid creation) from skin or lymph node explants. The method is based on the selective harvesting of melanocytes and melanoma cells emigrating from the cultured explants.

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Background: 3D bioprinting is the future of constructing functional organs. Creating a bioactive scaffold with pancreatic islets presents many challenges. The aim of this paper is to assess how the 3D bioprinting process affects islet viability.

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This article presents possible applications of a dynamic gravity meter (MGS-6, Micro-g LaCoste) for determining the dynamic height along the Odra River, in northwest Poland. The gravity measurement campaign described in this article was conducted on a small, hybrid-powered survey vessel (overall length: 9.5 m).

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The technology of tissue engineering is a rapidly evolving interdisciplinary field of science that elevates cell-based research from 2D cultures through organoids to whole bionic organs. 3D bioprinting and organ-on-a-chip approaches through generation of three-dimensional cultures at different scales, applied separately or combined, are widely used in basic studies, drug screening and regenerative medicine. They enable analyses of tissue-like conditions that yield much more reliable results than monolayer cell cultures.

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Introduction: 3D printing is being used more extensively in modern biomedicine. One of the problems is selecting a proper crosslinking method of bioprinted material. Amongst currently used techniques we can distinguish: physical crosslinking (e.

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Introduction: The extracellular matrix (ECM) consists, among others, of polysaccharides, glycosaminoglycans, and proteins. It is being increasingly used in tissue bioengineering. Obtaining ECM of the highest quality through decellularization is a big challenge because of some differences in organ structure.

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Type 1 diabetes (T1D) is the third most common autoimmune disease which develops due to genetic and environmental risk factors. Based on the World Health Organization (WHO) report from 2014 the number of people suffering from all types of diabetes ascended to 422 million, compared to 108 million in 1980. It was calculated that this number will double by the end of 2030.

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A porphycene-derived compound with a 20 π-electron skeleton has been obtained by replacing two pyrrolene units of porphycene by pyridine rings. NMR, electronic absorption and MCD spectra, and the lack of fluorescence are typical for 4 N cyclic π electron systems. The electronic structure and the differences with respect to porphycene can be rationalized by treating these compounds as perturbed, doubly positively charged [22]annulene and [20]annulene perimeters, respectively.

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Overcoming the problem of vascularization remains the main challenge in the field of tissue engineering. As three-dimensional (3D) bioprinting is the rising technique for the fabrication of large tissue constructs, small prevascularized building blocks were generated that can be incorporated throughout a printed construct, answering the need for a microvasculature within the small micron range (<10 μm). Uniform spheroids with an ideal geometry and diameter for bioprinting were formed, using a high-throughput non-adhesive agarose microwell system.

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Unlabelled: In this study, we isolated 28 yeast strains from samples of plant material and fermented food and evaluated the possibility of efficient production of 2-phenylethanol (2-PE) in the organic waste-based media supplemented with l-phenylalanine (l-Phe). We used whey, a by-product from milk processing, as a base for media, and either glucose or three by-products from sugar beet processing as a fermentable carbon source. Ten newly isolated yeast strains were capable of producing over 2 g l 2-PE through the l-Phe biotransformation in a batch mode in standard medium.

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We compare the absorption and magnetic circular dichroism (MCD) spectra of a series of porphyrin oligomers - dimer, tetramer, and hexamer - bound in a linear or cyclic fashion. The MCD signal is extremely weak for low energy transitions in the linear oligomers, but it is amplified when the cyclic porphyrin hexamer binds a template, restricting rotational freedom. The appearance of Faraday A terms in the MCD spectra demonstrates the presence of a magnetic moment, and thus, uncompensated electronic current.

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Bacteria of the genus Proteus of the family Enterobacteriaceae are facultative human pathogens responsible mainly for urinary tract and wound infections, bacteremia and the development of rheumatoid arthritis (RA). We have analyzed and compared by ELISA the titer of antibodies in plasmas of healthy individuals and in sera of rheumatoid arthritis patients recognizing a potential host cross-reactive epitope (lysine-galacturonic acid epitopes) present in Proteus lipopolysaccharide (LPS). In our experiments LPSs isolated from two mutants of smooth Proteus mirabilis 1959 (O3), i.

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Three octaalkyl-substituted cyclo[4]naphthobipyrroles, studied in solution in the form of their sulfates, reveal absorption and magnetic circular dichroism (MCD) spectra very similar to those of the parent cyclo[8]pyrrole. A unique feature of these systems is a strong absorption in the near IR region. The analysis of MCD patterns based on a perimeter model reveals a hard-chromophore character of cyclo[4]naphthobipyrroles, i.

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Screening approaches adopted in pharmaceutical companies for chiral LC method development may be quite complicated and sophisticated in order to guarantee a high success rate. However in other environments it may be of more value to assess how simple a screen might be used to still have a good chance of achieving success. The genuine need to develop chiral separations for the former 'legal-high' drug mephedrone and related cathinones of topical interest presented a good opportunity to develop this theme.

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This paper reports the development of the new technique of Raman linear difference (RLD) spectroscopy and its application to small molecules: anthracene and nucleotides adenosine-5'-monophosphate, thymidine-5'-monophosphate, guanosine-5'-monophosphate, and cytidine-5'-monophosphate. In this work we also present a new alignment method for Raman spectroscopy where stretched polyethylene films are used as the matrix. Raman spectra using light polarized along the orientation direction and perpendicular to it are reported.

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In the present work, the validity of the helicity rule relating the absolute configuration of the bridgehead carbon atom in bicyclic β-lactams to the sign of the 220 nm band observed in their electronic circular dichroism (ECD) spectra is examined for ring-expanded cephalosporin analogues. To this end, a series of model compounds with a seven-membered ring condensed with the β-lactam unit was synthesized. A key step of their synthesis was either the ring-closing metathesis (RCM) or the free radical cyclization leading to the seven-membered ring with an S, O, or C atom at the 6 position in the bicyclic skeleton.

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It is well known that the biological activity of clavams depends strongly on the absolute configuration at the ring junction carbon atom. Therefore, development of the efficient stereo-controlled synthetic methods for the new oxygen analogs of penams, and the structure-activity relationship studies call for a reliable determination of the absolute stereochemistry of newly synthesized compounds. Recently, we proposed an empirical helicity rule relating the configuration of the bridgehead carbon atom to the sign of the 240 nm band observed in the electronic circular dichroism (ECD) spectrum of clavams.

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The biological activity of bicyclic beta-lactam antibiotics depends strongly on the absolute configuration of the bridgehead carbon atom. Frelek and co-workers proposed an empirical helicity rule relating the configuration of the bridgehead carbon atom to the sign of the 220 nm band in the electronic circular dichroism (CD) spectrum of beta-lactams. Here we use synthetic organic chemistry, CD spectroscopy, and time-dependent density functional theory (TDDFT) to investigate the validity of this structure-property relationship for eight model compounds.

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