Bardoxolone methyl displays detrimental effects on endothelial bioenergetics, suppresses endothelial ET-1 release, and increases endothelial permeability in human microvascular endothelium

Nrf2 is a master regulator of antioxidant cellular defence, and agents activating the Nrf2 pathway have been tested in various diseases. However, unexpected side effects of cardiovascular nature reported for bardoxolone methyl in patients with type 2 diabetes mellitus and stage 4 chronic kidney disease (the BEACON trial) still have not been fully explained. Here, we aimed to characterize the effects of bardoxolone methyl compared with other Nrf2 activators- dimethyl fumarate and Lsulforaphane - on human microvascular endothelium. Endothelial toxicity, bioenergetics, mitochondrial membrane potential, endothelin-1 (ET-1) release, endothelial permeability, Nrf2 expression, and ROS production were assessed in human microvascular endothelial cells (HMEC-1) incubated for 3 and 24 hours with 100nM-5 μM of either bardoxolone methyl, dimethyl fumarate, or L-sulforaphane. Three-hour incubation with bardoxolone methyl (100nM-5 μM), although not toxic to endothelial cells, significantly affected endothelial bioenergetics by decreasing mitochondrial membrane potential (concentrations ≥ 3 μM), decreasing spare respiratory capacity (concentrations ≥ 1 μM), and increasing proton leak (concentrations ≥ 500nM), while dimethyl fumarate and L-sulforaphane did not exert such actions. Bardoxolone methyl at concentrations ≥ 3 μM also decreased cellular viability and induced necrosis and apoptosis in the endothelium upon 24-hour incubation. In turn, endothelin-1 decreased permeability in endothelial cells in picomolar range, while bardoxolone methyl decreased ET-1 release and increased endothelial permeability even after short-term (3 hours) incubation. In conclusion, despite that all three Nrf2 activators exerted some beneficial effects on the endothelium, as evidenced by a decrease in ROS production, bardoxolone methyl, the most potent Nrf2 activator among the tested compounds, displayed a distinct endothelial profile of activity comprising detrimental effects on mitochondria and cellular viability and suppression of endothelial ET-1 release possibly interfering with ET-1-dependent local regulation of endothelial permeability

Shadow banks and the financial stability in Poland

Celem niniejszej pracy jest przybliżenie działalności instytucji parabankowych i ich wpływu na stabilność finansową w Polsce. Przedstawiono zalety i wady tych podmiotów oraz etapy rozwoju parabanków na polskim rynku usług finansowych. Praca wyjaśnia też przyczyny wzrostu popularności parabanków w Polsce. Motywem podjęcia przez autora tego tematu była chęć omówienia podmiotów finansowych działających na polskim rynku bez regulacji oraz nadzoru finansowego, o których stało się głośno w Polsce zwłaszcza po upadku spółki Amber Gold w 2012 r. Autor niniejszej pracy stawia tezę, że instytucje parabankowe wpływają na wzrost niestabilności finansowej, a ich działalność w Polsce nie jest dostatecznie uregulowana. W celu potwierdzenia tej tezy prześwietlono działalność parabanków na polskim rynku finansowym oraz skalę nadzoru nad tymi podmiotami, a następnie zaprezentowano wnioski z tej analizy.The purpose of this thesis is to present the operations of shadow banks and their influence on the financial stability in Poland. The advantages and disadvantages of these institutions and the stages of development in the Polish market of financial services are presented here. This thesis also clarifies the reasons for the growth of popularity of shadow banks in Poland. The motive for investigating this topic was to discuss the financial institutions which operate on the Polish market with neither regulations nor financial supervision. These entities have been a major issue in Poland especially after the bankruptcy of Amber Gold in 2012. The author proposes the thesis that shadow banks have an impact on the growth of financial instability and that their operations in Poland are not adequately regulated. In order to confirm this assumption the author has investigated the operations of shadow banks in the Polish financial market and the scale in which these institutions are supervised. Conclusions from the conducted analysis are included in the final chapter

Venture capital funds as a source of funding for small and medium enterprises in Europe and Poland

Celem niniejszej pracy jest przybliżenie działalności funduszy venture capital i ich zakresu wykorzystania w sektorze małych i średnich przedsiębiorstw w Europie i Polsce. Przedstawiono wady i zalety tej metody pozyskiwania kapitału oraz etapy rozwoju funduszy venture capital na europejskim i polskim rynku kapitałowym. Motywem podjęcia przez autora tego tematu była chęć przedstawienia zakresu wykorzystania tych inwestycji w europejskim i polskim sektorze MSP. Autor niniejszej pracy stawia tezę, że pomimo ciągłego rozwoju inwestycji venture capital w Europie i Polsce, ich potencjał nie jest w pełni wykorzystywany, a większość małych i średnich przedsiębiorców wybiera inne źródła pozyskiwania kapitału. W celu potwierdzenia tej tezy prześwietlono działalność inwestycji venture capital oraz skalę ich wykorzystania przez europejski i polski sektor MSP.The purpose of this thesis is to present the operations of venture capital funds and their level of implementation in the small and medium enterprise sector in both Europe and Poland. The advantages and disadvantages of this method of employing resources as well as the stages of venture capital development in the European and Polish SME are presented here. The motive for investigating this topic was to discuss the level of implementation of these investments in the European and Polish SME. The author proposes the thesis that in spite of an ongoing development of venture capital in Europe and Poland, its potential is still not efficiently utilised. In order to confirm this assumption the author has investigated the operations of venture capital investments as well as their level of implementation in the European and Polish SME

The application of image cytometry for the evaluation of the phenotype in cultured endothelial cells.

Śródbłonek stanowi wewnętrzną warstwę ścian naczyń krwionośnych, a zaburzenia jego funkcjonowania są obserwowane w przebiegu wielu chorób układu krążenia. Celem niniejszej pracy magisterskiej była próba zastosowania cytometrii obrazowej, w połączeniu z nowoczesnymi metodami analizy obrazu, do badania zmian fenotypu komórek śródbłonka hodowanych in vitro. W pierwszym etapie badań, za pomocą algorytmów analizy tekstury, sprawdzono możliwość wykrywania zmian w strukturze filamentów aktynowych cytoszkieletu komórek linii GM-7373 po inkubacji z substancjami mającymi udowodniony wpływ na cytoszkielet (jasplakinolid i cytochalazyna D). Cztery z czternastu zastosowanych algorytmów pozwoliły zaobserwować zmiany, jednak skuteczność badanych narzędzi okazała się mniejsza w porównaniu z innymi metodami opisywanymi w literaturze. Następnie zbadano zmiany potencjału mitochondrialnego komórek linii HMEC-1 po inkubacji ze związkiem rozprzęgającym mitochondria (FCCP) oraz wybranymi aktywatorami czynnika transkrypcyjnego Nrf-2, takimi jak: bardoksolon, fumaran dimetylu i L-sulforafan. Do badań wykorzystano dwa barwniki wrażliwe na zmiany potencjału – Rodaminę 123 i JC-1. Potwierdzono użyteczność cytometrii obrazowej do oceny zmian potencjału mitochondrialnego.W ostatnim etapie badań oceniono możliwość badania zmian w strukturze glikokaliksu za pomocą przeciwciała przeciw siarczanowi heparanu (F58-10E4). Zobrazowano zmiany w glikokaliksie komórek linii EA.hy926. Zmiany nie były obserwowane w komórkach linii HMEC-1. Niniejsza praca ukazuje szerokie możliwości zastosowania cytometrii obrazowej do oceny fenotypu komórek śródbłonka hodowanych in vitro. Technika ta może być wykorzystywana do oceny śródbłonkowego działania związków będących kandydatami na leki jako element tzw. high-content screening (HCS).The endothelium is an inner layer of the blood vessel. Its dysfunction is observed in several cardiovascular diseases. The aim of this thesis was to test the application of image cytometry, combined with modern image analysis methods, for detection of changes in the phenotype of the endothelial cells cultured in vitro.In the first phase, algorithms for texture analysis were used to detect changes in the structure of cytoskeletal actin filaments in GM-7373 cells previously incubated with jasplakinolide or cytochalasin D – substances that affect the cytoskeleton. The effects were observed using four out of fourteen algorithms. However, the applied method is less sensitive than the others described in the literature.Afterwards, alterations of mitochondrial potential in HMEC-1 cells were measured after administration of mitochondrial uncoupler (FCCP) or selected activators of transcriptional factor Nrf-2 – bardoxolone, dimethyl fumarate and L-sulforaphane. For this purpose, two fluorescent dyes (Rhodamine 123 and JC-1), which are sensitive to changes in mitochondrial potential, were used. The utility of image cytometry in this type of research was confirmed. In the last stage of experiments, the utility of Ab Heparan Sulfate (F58-10E4), in terms of detecting changes in the structure of glycocalyx, was evaluated. The breakdown of the structure was observed in EA.hy926 cells, but the effect was not observed in HMEC-1 cells.This study presents wide range application of image cytometry for the evaluation of the phenotype in cultured endothelial cells. Described method appears to be suitable for evaluation of endothelial activity of drug candidates in high-content screening

Comparison of selected point estimators of vibration signals for purposes of fault detection in rolling bearings

Most of machine breakdowns relate to bearing failures thus it is very important to diagnose bearing conditions. The main purpose of the study was to classify the condition of bearings and identify defective ones based on visual inspection and the values of classic parameters of the acceleration signal vibration, such as Peak, RMS, Kurtosis. The results were compared to parameters provided by the SPM method. All vibration parameters were estimated for high pass filtered signals where filters had following cut-off frequencies 0.5; 1, 2, 5 and 8 kHz. Bearings were tested on the laboratory test bench being built at the Silesian University of Technology. Based on the signal analysis and visual inspections it can be stated that there is agreement in the assessment of the conditions between the parameters of the SPM method and the Peak and RMS parameters. It was observed that the sensitivity to the existence of low-intensity defects increases when the vibration parameters are determined for signals in the band above 2kHz

Synthesis, molecular docking and antiplasmodial activities of new tetrahydro-ΒCarbolines

Malaria is still one of the most dangerous infectious diseases and the emergence of drug resistant parasites only worsens the situation. A series of new tetrahydro-β-carbolines were designed, synthesized by the Pictet–Spengler reaction, and characterized. Further, the compounds were screened for their in vitro antiplasmodial activity against chloroquine-sensitive (D10) and chloroquine-resistant (W2) strains of Plasmodium falciparum. Moreover, molecular modeling studies were performed to assess the potential action of the designed molecules and toxicity assays were conducted on the human microvascular endothelial (HMEC-1) cell line and human red blood cells. Our studies identified N-(3,3-dimethylbutyl)-1-octyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b] indole-3-carboxamide (7) (a mixture of diastereomers) as the most promising compound endowed with the highest antiplasmodial activity, highest selectivity, and lack of cytotoxicity. In silico simulations carried out for (1S,3R)-7 provided useful insights into its possible interactions with enzymes essential for parasite metabolism. Further studies are underway to develop the optimal nanosized lipid-based delivery system for this compound and to determine its precise mechanism of action