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Piotr Orlowski,1 Magdalena Zmigrodzka,2 Emilia Tomaszewska,3 Katarzyna Ranoszek-Soliwoda,3 Beata Pajak,4 Anna Slonska,5 Joanna Cymerys,5 Grzegorz Celichowski,3 Jaroslaw Grobelny,3 Malgorzata Krzyzowska1 1Laboratory of Nanobiology and Biomaterials, Military Institute of Hygiene and Epidemiology, Warsaw, Poland; 2Department of Pathology and Veterinary Diagnostics, Institute of Veterinary Medicine, Warsaw University of Life Sciences (WULS-SGGW), Warsaw, Poland; 3Department of Materials Technology and Chemistry, Faculty of Chemistry, University of Lodz, Lodz, Poland; 4Laboratory of Genetics and Molecular Biology, Military Institute of Hygiene and Epidemiology, Warsaw, Poland; 5Division of Microbiology, Department of Preclinical Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw 02-786, PolandCorrespondence: Malgorzata Krzyzowska Email krzyzowskam@yahoo.comBackground: Polyphenols possess antioxidant, anti-inflammatory and antimicrobial properties and have been used in the treatment of skin wounds and burns. We previously showed that tannic acid-modified AgNPs sized > 26 nm promote wound healing, while tannic acid-modified AgNPs sized 13 nm can elicit strong local inflammatory response. In this study, we tested bimetallic Au@AgNPs sized 30 nm modified with selected flavonoid and non-flavonoid compounds for wound healing applications.Methods: Bimetallic Au@AgNPs were obtained by growing an Ag layer on AuNPs and further modified with selected polyphenols. After toxicity tests and in vitro scratch assay in HaCaT cells, modified lymph node assay as well as the mouse splint wound model were further used to access the wound healing potential of selected non-toxic modifications.Results: Tannic acid, gallic acid, polydatin, resveratrol, catechin, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate and procyanidin B2 used to modify Au@AgNPs exhibited good toxicological profiles in HaCaT cells. Au@AgNPs modified with 15 μM tannic acid, 200 μM resveratrol, 200 μM epicatechin gallate, 1000 μM gallic acid and 200 μM procyanidin B2 induced wound healing in vivo and did not lead to the local irritation or inflammation. Tannic acid-modified Au@AgNPs induced epithelial-to-mesenchymal transition (EMT) – like re-epithelialization, while other polyphenol modifications of Au@AgNPs acted through proliferation and wound closure.Conclusion: Bimetallic Au@AgNPs can be used as a basis for modification with selected polyphenols for topical uses. In addition, we have demonstrated that particular polyphenols used to modify bimetallic nanoparticles may show different effects upon different stages of wound healing.Keywords: polyphenols, bimetallic nanoparticles, wound healing, mouse model

In this study, molybdenum(IV) sulfide (MoS2) nanoparticles (97 ± 32 nm) and microparticles (1.92 ± 0.64 μm) stabilized with poly (vinylpolypyrrolidone) (PVP) were administered intratracheally to male and female rats (dose of 1.5 or 5 mg/kg bw), every 14 days for 90 days (seven administrations in total). Blood parameters were assessed during and at the end of the study (hematology, biochemistry including glucose, albumins, uric acid, urea, high density lipoprotein HDL, total cholesterol, triglycerides, aspartate transaminase, and alanine transaminase ALT). Bronchoalveolar lavage fluid (BALF) analyses included cell viability, biochemistry (total protein concentration, lactate dehydrogenase, and glutathione peroxidase activity), and cytokine levels (tumor necrosis factor α, TNF‐α, macrophage inflammatory protein 2‐alpha, MIP‐2, and cytokine‐induced neutrophil chemoattractant‐2, CINC‐2). Tissues were subjected to routine histopathological and electron microscopy (STEM) examinations. No overt signs of chronic toxicity were observed. Differential cell counts in BALF revealed no significant differences between the animal groups. An increase in MIP‐2 and a decrease in TNF‐α were observed in BALF in the exposed males. The histopathological changes in the lung evaluated according to a developed classification system (based on severity of inflammation, range 0–4, with 4 indicating the most severe changes) showed average histopathological score of 1.33 for animals exposed to nanoparticles and microparticles at the lower dose, 1.72 after exposure to nanoparticles at the higher dose, and 2.83 for animals exposed to microparticles at the higher dose. In summary, it was shown that nanosized and microsized MoS2 can trigger dose‐dependent inflammatory reactions in the lungs of rats after multiple intratracheal instillation irrespective of the animal sex. Some evidence indicates a higher lung pro‐inflammatory potential of the microform. Molybdenum(IV) sulfide (MoS2) nanoparticles and microparticles administered intratracheally to rats (1.5 or 5 mg/kg bw), every 14 days for 90 days, induced no overt signs of systemic chronic toxicity. An increase in MIP‐2 and a decrease in TNF‐α were observed in BALF in the exposed males. Based on histopathological examination, nanosized and microsized MoS2 can trigger dose‐dependent inflammatory reactions in the lungs of rats after multiple intratracheal instillations, with a slightly higher lung pro‐inflammatory potential of the microform. [ABSTRACT FROM AUTHOR]

Piotr Orlowski,1 Magdalena Zmigrodzka,2 Emilia Tomaszewska,3 Katarzyna Ranoszek-Soliwoda,3 Monika Czupryn,1 Malgorzata Antos-Bielska,1 Janusz Szemraj,4 Grzegorz Celichowski,3 Jaroslaw Grobelny,3 Malgorzata Krzyzowska1 1Military Institute of Hygiene and Epidemiology, Warsaw, Poland; 2Department of Pathology and Veterinary Diagnostics, Faculty of Veterinary Medicine, Warsaw University of Life Sciences (WULS-SGGW), Warsaw, Poland; 3Department of Materials Technology and Chemistry, Faculty of Chemistry, University of Lodz, Lodz, Poland; 4Bionanopark, Lodz, Poland Introduction: Silver nanoparticles (AgNPs) have been shown to promote wound healing and to exhibit antimicrobial properties against a broad range of bacteria. In our previous study, we prepared tannic acid (TA)-modified AgNPs showing a good toxicological profile and immunomodulatory properties useful for potential dermal applications.Methods: In this study, in vitro scratch assay, antimicrobial tests, modified lymph node assay as well as a mouse splint wound model were used to access the wound healing potential of TA-modified and unmodified AgNPs.Results: TA-modified but not unmodified AgNPs exhibited effective antibacterial activity against Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli and stimulated migration of keratinocytes in vitro. The tests using the mouse splint wound model showed that TA-modified 33 and 46 nm AgNPs promoted better wound closure, epithelialization, angiogenesis and formation of the granulation tissue. Additionally, AgNPs elicited expression of VEGF-α, PDGF-β and TGF-β1 cytokines involved in wound healing more efficiently in comparison to control and TA-treated wounds. However, both the lymph node assay and the wound model showed that TA-modified AgNPs sized 13 nm can elicit strong inflammatory response not only during wound healing but also when applied to the damaged skin.Conclusion: TA-modified AgNPs sized >26 nm promote wound healing better than TA-modified or unmodified AgNPs. These findings suggest that TA-modified AgNPs sized >26 nm may have a promising application in wound management. Keywords: hydrolyzable tannin, split wound, silver, antimicrobials, inflammation, fibroblasts, monocytes

Thermo-optic properties enhancement of the bi-stable temperature threshold sensors based on a partially filled photonic crystal fiber was reported. Previously tested transducers filled with a selected group of pure n-alkanes had in most cases differences between switching ON and OFF states. Therefore, the modification of filling material by using additional crystallization centers in the form of gold nanoparticles was applied to minimize this undesirable effect. The evaluation of the thermodynamic properties of pentadecane and its mixtures with 14 nm spherical Au nanoparticles based on the differential scanning calorimetry measurements was presented. Optical properties analysis of sensors prepared with these mixtures has shown that they are bounded with refractive index changes of the filling material. Particular sensor switches ON before melting process begins and switches OFF before crystallization starts. Admixing next group of n-alkanes with these nanoparticles allows to design six sensors transducers which change ON and OFF states at the same temperature. Thus, the transducers with a wider temperature range for fiber-optic multi- threshold temperature sensor tests will be used. [ABSTRACT FROM AUTHOR]

Scatter plots of facilities on the plane are derived from a heuristic procedure proposed by Drezner. Features of this approach have been investigated. It is shown that scatter plots generated by the 'eigenvectors method' could differ in quality. It is shown that this quality depends on the input data structure. By the comparison of eigenvector results with those obtained by a special algorithm proposed in this work, general conditions are determined for rational applications of the Drezner approach. [ABSTRACT FROM AUTHOR]