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281.
Since proteases are involved in a wide range of physiological and disease states, the development of novel tools for imaging proteolytic enzyme activity is attracting increasing interest from scientists. Peptide substrates containing proteinogenic amino acids are often the first line of defining enzyme specificity. This Minireview outlines examples of major recent advances in probing proteases using unnatural amino acid residues, which greatly expands the possibilities for designing substrate probes and inhibitory activity‐based probes. This approach already yielded innovative probes that selectively target only one active protease within the group of enzymes exhibiting similar specificity both in cellular assays and in bioimaging research. 相似文献
282.
Anna Kroma Mariola Pawlaczyk Agnieszka Feliczak-Guzik Maria Urbaska Dorota Jenerowicz Agnieszka Seraszek-Jaros Magorzata Kikowska Justyna Gornowicz-Porowska 《Molecules (Basel, Switzerland)》2022,27(11)
Phytoecdysones from Serratula coronata seem to be promising agents for skincare in patients with psoriasis. The aim of the study was to determine the effects of creams containing the extract of S. coronata on psoriatic lesions. Creams with different formulas were prepared: 0-Lekobaza®, 1-Lekobaza®, S. coronata, 2-Lekobaza®, Salicylic acid, 3-Lekobaza®, S. coronata, Salicylic acid. After examination of skin penetration and biosafety, the designated cream was applied twice daily for 6 weeks on 72 psoriatic plaques located on elbows or knees. The lesions were assessed at baseline and follow-up of 6 weeks. The lesions area was measured, and severity of scaling, erythema, and infiltration was assessed using a 5-point scale (from 0—none to 4—very severe). Skin hydration and structure, pH, transepidermal water loss, erythema, and melanin index were analyzed instrumentally. Creams 1, 2, and 3 significantly reduced the area of psoriatic plaques. Improvement in erythema and infiltration was observed for creams 1 and 3. Creams 1–3 reduced scaling. Our study confirmed a beneficial effect of creams containing S. coronata extract on psoriatic lesions. 相似文献
283.
Marta Karkoszka Jakub Rok Klaudia Banach Justyna Kowalska Zuzanna Rzepka Dorota Wrzeniok 《Molecules (Basel, Switzerland)》2022,27(13)
Meloxicam (MLX), which belongs to the oxicam nonsteroidal anti-inflammatory drug derivatives, is an inhibitor of the cyclooxygenase-2 (COX-2) enzyme. Cutaneous adverse effects caused by interaction between UVA radiation and exogenous factors can manifest as phototoxic reactions. Phototoxicity may be a reason for the accumulation of genetic and molecular changes in long-lived cells with low proliferation potential, leading to tumor development. There are several potentially phototoxic drugs, the active component of which is meloxicam. The research aimed to evaluate the influence of MLX and UVAR on skin cells—fibroblasts and melanocytes homeostasis. The obtained results indicated that co-treatment with MLX and UVAR inhibited skin cell proliferation, proportionally to the drug concentration. The observation was confirmed by cytometric analysis of the cell number and viability. The phototoxic effect of MLX was revealed in morphological changes. It was stated that MLX with UVAR lowered the mitochondrial transmembrane potential and changed the cell cycle profile. Additionally, MLX and UVAR caused the disruption of redox homeostasis by lowering the intracellular level of reduced thiols. The presented study revealed that the phototoxic activity of MLX is associated with oxidative stress induction and disruptions in cell homeostasis. The differences in the phototoxic effects of MLX at the cellular level may be related to the different content of melanin pigments. 相似文献
284.
ukasz Cichocki Dorota Warmiska Justyna uczak Andrzej Przyjazny Grzegorz Boczkaj 《Molecules (Basel, Switzerland)》2022,27(13)
The paper presents a new method for evaluating the polarity and hydrophobicity of deep eutectic solvents (DESs) based on the measurement of the DES contact angle on glass. DESs consisting of benzoic acid derivatives and quaternary ammonium chlorides–tetrabutylammonium chloride (TBAC) and benzyldimethylhexadecylammonium chloride (16-BAC)—in selected molar ratios were chosen for the study. To investigate the DESs polarity, an optical goniometer and an solvatochromic scale based on Reichardt’s dye were used. The research demonstrated the high accuracy and precision of the developed procedure. The simplicity of the examination and the availability of basic equipment allow for the implementation of the developed method in routine investigations of DESs. 相似文献
285.
Barbara Breza-Boruta Anna Ligocka Justyna Bauza-Kaszewska 《Molecules (Basel, Switzerland)》2022,27(13)
Compared to conventional agriculture, organic farming is believed to provide a higher nutritional and health value in its products due to the elimination of harmful contaminants (pesticides, nitrates, heavy metals, etc.). Numerous studies have been conducted to show how the production system affects the quality of food in terms of the content of bioactive compounds. The aim of this study was to compare the content of some bioactive compounds (vitamin C, β-carotene, Ca content) and lactic acid bacteria (LAB) number and their bacteriocinogenic activity in organic and conventional fermented food. Although the results do not provide an unambiguous conclusion regarding the superiority of one production system over the other, the LAB number in organic pickled carrot juice, sauerkraut, yogurt, and kefir was higher than in their conventional counterparts. Their bacteriocinogenic potential against selected pathogens was also higher in most organic products. Organic vegetables contained significantly more vitamin C, and the calcium content in the organic yogurt was higher compared to the conventional version of the product. Relatively similar concentrations of ß-carotene for both production systems were found in carrot juice, while in organic pickled beet juice, there was five-fold less ß-carotene than in conventional juice. 相似文献
286.
Iwona Kwiatkowska Justyna Magdalena Hermanowicz Zaneta Iwinska Krystyna Kowalczuk Jolanta Iwanowska Dariusz Pawlak 《Molecules (Basel, Switzerland)》2022,27(13)
A thorough understanding of cancer pathogenesis is a necessary step in the development of more effective and safer therapy. However, due to the complexity of the process and intricate interactions, studying tumor development is an extremely difficult and challenging task. In bringing this issue closer, different scientific models with various advancement levels are helpful. Cell cultures is a system that is too simple and does not allow for multidirectional research. On the other hand, rodent models, although commonly used, are burdened with several limitations. For this reason, new model organisms that will allow for the studying of carcinogenesis stages and factors reliably involved in them are urgently sought after. Danio rerio, an inconspicuous fish endowed with unique features, is gaining in importance in the world of scientific research. Including it in oncological research brings solutions to many challenges afflicting modern medicine. This article aims to illustrate the usefulness of Danio rerio as a model organism which turns out to be a powerful and unique tool for studying the stages of carcinogenesis and solving the hitherto incomprehensible processes that lead to the development of the disease. 相似文献
287.
Thermodynamic compatibility of actives encapsulated into PEG‐PLA nanoparticles: In Silico predictions and experimental verification 下载免费PDF全文
Andreas Erlebach Timm Ott Christoph Otzen Stephanie Schubert Justyna Czaplewska Ulrich S. Schubert Marek Sierka 《Journal of computational chemistry》2016,37(24):2220-2227
Achieving optimal solubility of active substances in polymeric carriers is of fundamental importance for a number of industrial applications, including targeted drug delivery within the growing field of nanomedicine. However, its experimental optimization using a trial‐and‐error approach is cumbersome and time‐consuming. Here, an approach based on molecular dynamics (MD) simulations and the Flory–Huggins theory is proposed for rapid prediction of thermodynamic compatibility between active species and copolymers comprising hydrophilic and hydrophobic segments. In contrast to similar methods, our approach offers high computational efficiency by employing MD simulations that avoid explicit consideration of the actual copolymer chains. The accuracy of the method is demonstrated for compatibility predictions between pyrene and nile red as model dyes as well as indomethacin as model drug and copolymers containing blocks of poly(ethylene glycol) and poly(lactic acid) in different ratios. The results of the simulations are directly verified by comparison with the observed encapsulation efficiency of nanoparticles prepared by nanoprecipitation. © 2016 Wiley Periodicals, Inc. 相似文献
288.
Karolina Grabowska Irma Podolak Agnieszka Galanty Daniel Załuski Justyna Makowska-Wąs Danuta Sobolewska 《Natural product research》2016,30(10):1219-1223
The in vitro anti-denaturation and anti-hyaluronidase activities of Impatiens parviflora extracts and isolated galactolipids (MGDG-1, DGDG-1) were investigated. This is the first report on these compounds in I. parviflora. All extracts showed anti-hyaluronidase activity, but only methanolic extract from fresh leaves exhibited significant activity against heat-induced denaturation of BSA in a dose-dependent manner. At 500 μg/mL, the extract and the reference drug showed 79.05% and 99.81% inhibition of protein denaturation, respectively. These results indicate that fresh leaves of I. parviflora may be beneficial in inflammatory conditions, especially those associated with protein denaturation, such as rheumatoid arthritis. The study revealed that only MGDG-1 showed weak activity in anti-denaturation assay but both galactolipids were potent inhibitors of hyaluronidase. MGDG-1 completely inhibited the enzyme activity at the concentration of 127.9 μg/mL. These results indicate the potential of galactolipids in the treatment of diseases associated with the loss of hyaluronic acid. 相似文献
289.
Kamiński ZJ Kolesińska B Kolesińska J Sabatino G Chelli M Rovero P Błaszczyk M Główka ML Papini AM 《Journal of the American Chemical Society》2005,127(48):16912-16920
A new generation of triazine-based coupling reagents (TBCRs), designed according to the concept of "superactive esters", was obtained by treatment of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium (DMTMM) chloride with lithium or silver tetrafluoroborate. The structure of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium tetrafluoroborate was confirmed by X-ray diffraction. Activation of carboxylic acids by using this reagent proceeds via triazine "superactive ester". The coupling reagent was successfully used for the synthesis of Z-, Boc-, and Fmoc-protected dipeptides derived from natural and unnatural sterically hindered amino acids and for fragment condensation, in 80-100% yield and with high enantiomeric purity. The manual SPPS of the ACP(65-74) peptide fragment (H-Val-Gln-Ala-Ala-Ile-Asp-Tyr-Ile-Asn-Gly-OH) proceeded significantly faster than with TBTU or HATU, as well as the automated SPPS of the same fragment gave a purer product than by using TBTU or PyBOP. The reagent was also demonstrated to be efficient in on-resin head-to-tail cyclization of constrained cyclopeptides, in SPPS synthesis of Aib peptides, and in the synthesis of esters from appropriate acids, alcohols, and phenols. The high efficiency and versatility of this new generation of TBCRs confirm, for the first time, the usefulness of the concept of "superactive esters" in rational design of the structure of coupling reagents. 相似文献
290.
Porous three‐dimensional collagen/chitosan scaffolds combined with poly (ethylene glycol) (PEG) and hydroxyapatite were obtained through a freeze‐drying method. Physical cross‐linking was examined by dehydrothermal treatment. The prepared materials were characterized by different analyses, eg, scanning electron microscopy (SEM), measurements of porosity and swelling, mechanical properties, and resistance to enzymatic degradation. The porosity of scaffolds and their swelling ratio decreased with the addition of hydroxyapatite. Moreover, after exposure to collagenase, the collagen/chitosan matrices containing PEG showed much faster degradation rate than matrices with the addition of hydroxyapatite. The results indicated that the addition of hydroxyapatite led to improvement of stiffness. The highest degree of porosity and swelling were demonstrated by collagen/chitosan/PEG matrices without hydroxyapatite. 相似文献