34 research outputs found
The effect of antioxidants on photoreactivity and phototoxic potential of RPE melanolipofuscin granules from human donors of different age
One of the most prominent age-related changes of retinal pigment epithelium (RPE) is the accumulation of melanolipofuscin granules, which could contribute to oxidative stress in the retina. The purpose of this study was to determine the ability of melanolipofuscin granules from younger and older donors to photogenerate reactive oxygen species, and to examine if natural antioxidants could modify the phototoxic potential of this age pigment. Electron paramagnetic resonance (EPR) oximetry, EPR-spin trapping, and time-resolved detection of near-infrared phosphorescence were employed for measuring photogeneration of superoxide anion and singlet oxygen by melanolipofuscin isolated from younger and older human donors. Phototoxicity mediated by internalized melanolipofuscin granules with and without supplementation with zeaxanthin and α-tocopherol was analyzed in ARPE-19 cells by determining cell survival, oxidation of cellular proteins, organization of the cell cytoskeleton, and the cell specific phagocytic activity. Supplementation with antioxidants reduced aerobic photoreactivity and phototoxicity of melanolipofuscin granules. The effect was particularly noticeable for melanolipofuscin mediated inhibition of the cell phagocytic activity. Antioxidants decreased the extent of melanolipofuscin-dependent oxidation of cellular proteins and disruption of the cell cytoskeleton. Although melanolipofuscin might be involved in chronic phototoxicity of the aging RPE, natural antioxidants could partially ameliorate these harmful effects
Increased oxidative stress in asthma - relation to inflammatory blood and lung biomarkers and airway remodeling indices
Airway inflammation in asthma is related to increased reactive oxygen species generation, potentially leading to tissue injury and subsequent airway remodeling. We evaluated oxidative stress in peripheral blood from asthmatic subjects (n = 74) and matched controls (n = 65), using recently developed real-time monitoring of the protein hydroperoxide (HP) formation by the coumarin boronic acid (CBA) assay. We also investigated the relation of the systemic oxidative stress response in asthma to disease severity, lung function, airway remodeling indices (lung computed tomography and histology), and blood and bronchoalveolar lavage fluid (BAL) inflammatory biomarkers. We documented enhanced systemic oxidative stress in asthma, reflected by 35% faster and 58% higher cumulative fluorescent product generation in the CBA assay (p < 0.001 for both). The dynamics of HP generation correlated inversely with lung function but not with asthma severity or histological measures of airway remodeling. HP generation was associated positively with inflammatory indices in the blood (e.g., C-reactive protein) and BAL (e.g., interleukin [IL]-6, IL-12p70, and neutrophil count). Bronchial obstruction, thicker airway walls, increased BAL IL-6, and citrullinated histone 3 in systemic circulation independently determined increased HP formation. In conclusion, a real-time CBA assay showed increased systemic HP generation in asthma. In addition, it was associated with inflammatory biomarkers, suggesting that proper disease control can also lead to a decrease in oxidative stress
Dermal exposure to immunostimulants induces changes in activity and proliferation of coelomocytes of Eisenia andrei
THE EFFICIENCY OF MARKETING METHODS IN THE ENVIRONMENT OF CULTURE INSTITUTES ON THE EXAMPLE OF MOCAK MUSEUM OF CONTEMPORARY ART IN KRAKOW
Rozdział I - Podstawy marketingu: przedstawienie podstawowych definicji i elementów marketingu, krótki rys historyczny ewolucji działań marketingowych, omówienie składników marketingu-mixRozdział II - Strategie marketingowe w instytucji: omówienie pięciu głównych strategii stosowanych w przedsiębiorstwach (strategie: normatywne, oparte na relacjach produkt-rynek, konkurencyjne, oparte na udziale instytucji w rynku, oparte na segmentacji rynku)Rozdział III - Instytucja kultury - podstawowe pojęcia i zagadnienia: przedstawienie podstaw prawnych funkcjonowania i organizacji instytucji kultury w Polsce.Rozdział IV - Metody marketingowe w kulturze: teoretyczne przedstawienie adaptacji metod marketingowych do środowiska instytucji kultury,Rozdział V - Metodologia badań własnych: przedstawienie celu badań (ocena skuteczności strategii marketingowej Muzeum, pod kątem postrzegania tych działań przez odbiorców oraz zbadanie efektywności tradycyjnych metod marketingowych w specyficznym środowisku instytucji kultury) hipotez (tradycyjne metody marketingowe, odpowiednio dopasowane do środowiska instytucji kultury nie tylko nie wpływają negatywnie na wypełnianie jej misji, ale pomagają w efektywnym jej funkcjonowaniu) i problemów badawczych oraz sposobów przeprowadzenia badań.Rozdział VI - Analiza i interpretacja wyników badań własnych: szczegółowe omówienie wyników badań odbiorców (ankiety oraz komentarzy internautów), oraz przedstawienie ich w formie graficznej. Analiza elementów strategii MOCAK-u oraz analiza odpowiedzi na pytania zawarte w kwestionariuszu. Badania wykazały jednoznacznie, że strategia marketingowa Muzeum spełnia swoje zadania, a działania MOCAK-u odbierane są pozytywnie. Wyniki potwierdziły główną hipotezę.Chapter I: Basic principles of marketing: presentation of basic elements of marketing, a brief history of evolution of marketing strategy, discussion of the components of the marketing mix.Chapter II: Marketing strategies in institutions: a discussion of the five main strategies used by companiesChapter III: Cultural institutions - basic issues: presentation of the legal basis for functioning and organization of cultural institutions in PolandChapter IV: Marketing methods in culture: Functioning of marketing methods in a cultural institutionChapter V: Research methodology: presentation of the purpose of the research, main hypotheses, and methods of conducting a research.Chapter VI: Analysis and interpretation of the research results: discussion of the results of the research of the recipients, Analysis of elements of the MOCAK's strategy. Research has clearly shown that the marketing strategy of the Museum fulfills its mission, and their actions are evaluated positively. The results confirmed the main hypothesis
Ethics in Photojournalism
WSTĘP: ogólne omówienie problematyki, wprowadzenie w zagadnienie etyki fotografii, objaśnienie metodologiiROZDZIAŁ I: Historia fotografii w Polsce i na świecie, przedstawienie technik, oraz sylwetek znanych fotografów.RODZIAŁ II: Przywołanie i omówienie wybranych regulacji międzynarodowych: Powszechna Deklaracja Praw Człowieka, Zasady etyki dziennikarskiej przygotowane pod egidą UNESCO, Deklaracja Zasad Międzynarodowej Federacji Dziennikarzy, a także zapisów w prawie polskim i amerykańskim obowiązujących fotoreporterów oraz kodesów etycznych opracowanych przez stowarzyszenia, takie jak: Amerykańskie Stowarzyszenie Fotografów Prasowych(NPPA), Amerykańskie Stowarzyszenie Fotografów Medialnych(ASMP), Stowarzyszenie Dziennikarzy Polskich, Rada Etyki Mediów. Rozdział zamyka omówienie wewnętrznych instrukcji dotyczących etyki w Associated Press i Agora S.ARODZIAŁ III: Omówienie pięciu wybranych zdjęć naruszających w różny sposób zapisy kodeksów (Kevin Carter: Strugging Girl, Gary Gross: A woman In The Child: Brooke Shields, Redakcja „Super Ekspressu”: Martwe ciało Waldemara Milewicza, Paul Hansen: Fabienne Cherisma, Narciso Contreras: Syrian opposition fighter)PODSUMOWANIEPreamble: Introduction to ethics and law in photojurnalismChapter I: History of photography, discussion on various techniques, famous phototographers achievementsChapter II: Discussion of chosen codesChapter III: Discussion of five chosen photographsSUMMAR
Melanopsin signaling pathway in HEK293 cell line with stable expression of human melanopsin : possible participation of phospholipase C beta 4 and diacylglycerol
Lipofuscin-mediated photic stress inhibits phagocytic activity of ARPE-19 cells; effect of donors' age and antioxidants
Inhibition of phagocytic activity of ARPE-19 cells by free radical mediated oxidative stress
SuperDopa (SD), SuperDopa amide (SDA) and Thioredoxin-mimetic peptides protect ARPE-19 cells from photic- and non-photic stress
Oxidative stress and inflammation in the retinal pigment epithelium (RPE) cells have been identified as significant risk factors in the development and progression of retinal associated diseases including age-related macular degeneration (AMD). In addition, AMD and myopia have been associated with impaired dopamine activity. Treatment of RPE cells with antioxidants or high concentrations of l-DOPA (levodopa), which down-regulates vascular endothelial growth factor (VEGF) via a G-protein-coupled receptor GPR143, slow AMD progression. To develop a targeted and effective treatment aimed at improving the viability of RPE cells we examined small molecular weight thiol-based and levodopa containing molecules. These include the N-acetylcysteine amide (AD4/NACA), SuperDopa-Amide (SDA), and members of the thioredoxin mimetic (TXM) family of peptides, TXM-CB13, TXM-CB30, and SuperDopa (SD). We show that these antioxidant/anti-inflammatory reagents protect ARPE-19 cells from photic stress mediated by rose Bengal (rB) and rhodopsin-rich POS, and from non-photic stress induced by oxidation with sodium iodate. Protection is correlated with a reduction in DPPH radical and singlet-oxygen quenching. Compared to GSH the bimolecular rate-constants of singlet oxygen quenching in aqueous solution by the levodopa derivatives SD and SDA were two-fold higher. Inhibition of auranofin-induced activation of the mitogen-activation-kinases (MAPK's) JNK1/2 and ERK1/2 confirmed the antioxidant/anti-inflammatory activity of the thiol-levodopa derivatives. The antioxidant and radical scavenging activities of TXM-CB13 and TXM-CB30, or SD and SDA, which combine redox activity with elevating cellular levodopa, might offer an efficient protection of RPE cells. These retino-protective peptides are potential drug candidates destined for slowing the onset and/or progression of RPE-related disorders