P590The NO-donor SNAP exerts cardioprotection against ischemia/reperfusion injury in human embryonic stem cell-derived cardiomyocytes

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Antibody-Directed Lentiviral Gene Transduction for Live-Cell Monitoring and Selection of Human iPS and hES Cells

The identification of stem cells within a mixed population of cells is a major hurdle for stem cell biology–in particular, in the identification of induced pluripotent stem (iPS) cells during the reprogramming process. Based on the selective expression of stem cell surface markers, a method to specifically infect stem cells through antibody-conjugated lentiviral particles has been developed that can deliver both visual markers for live-cell imaging as well as selectable markers to enrich for iPS cells. Antibodies recognizing SSEA4 and CD24 mediated the selective infection of the iPS cells over the parental human fibroblasts, allowing for rapid expansion of these cells by puromycin selection. Adaptation of the vector allows for the selective marking of human embryonic stem (hES) cells for their removal from a population of differentiated cells. This method has the benefit that it not only identifies stem cells, but that specific genes, including positive and negative selection markers, regulatory genes or miRNA can be delivered to the targeted stem cells. The ability to specifically target gene delivery to human pluripotent stem cells has broad applications in tissue engineering and stem cell therapies

Drying and rehydration of oyster mushroom

Dehydration and rehydration processes of Pleurotus ostreatus fruiting bodies were investigated in this work. Mushroom samples were dehydrated at 40, 50 and 60 ºC, using drying air with relative humidity of 75 %. The rehydration was investigated at different temperatures of immersion water (25, 55 and 85 ºC) and different immersion times (30, 75 and 120 minutes). The best rehydration occurred for the samples dried at 40 ºC. The rehydration could be done in water at room temperature, during 30 minutes. Water sorption isotherms of samples were determined at 30, 40 and 50 ºC. Both GAB and BET models satisfactorily represented the experimental data of moisture sorption of dried mushrooms.Processos de desidratação e de rehidratação de cogumelos da espécie Pleurotus ostreatus foram avaliados neste trabalho. Os cogumelos foram desidratados a 40, 50 e 60 ºC, com umidade relativa do ar de 75 %. O processo de rehidratação foi avaliado para diferentes temperaturas de água de imersão (25, 55 e 85 ºC) e diferentes tempos de imersão (30, 75 e 120 minutos). A melhor temperatura de secagem foi 40 ºC, levando em consideração a melhor rehidratação dos cogumelos desidratados nesta temperatura. A rehidratação pode ser feita em água a temperatura ambiente, por 30 minutos. Isotermas de sorção de umidade de amostras foram determinadas a 30, 40 e 50 ºC.Tanto o modelo de GAB quanto o de BET representaram satisfatoriamente os dados experimentais de isoterma de sorção de umidade

In-vitro effect of flavonoids from Solidago canadensis extract on glutathione S-transferase

Solidago canadensis is typical of a flavonoid-rich herb and the effect of an aqueous ethanol extract on glutathione-S-transferase (GST) activity using HepG2 cells was compared with those of the flavonol quercetin and its glycosides quercitrin and rutin, found as major constituents. The composition of the extract was determined by HPLC and rutin was found to be the major flavonoidal component of the extract. Total GST activity was assessed using 1-chloro-2,4-dinitrobenzene as a substrate. The glycosides rutin and quercitrin gave dose-dependent increases in GST activity, with a 50% and 24.5% increase at 250 mm, respectively, while the aglycone quercetin inhibited the enzyme by 30% at 250 mm. The total extract of the herb gave an overall dose-dependent increase, the fractions corresponding to the flavonoids showed activating effects while those containing caffeic acid derivatives were inhibitory. The activity observed corresponds to that reported for similar compounds in-vivo using rats, thus the HepG2 cell line could serve as a more satisfactory method of assessing the effects of extracts and compounds on GS

LC-MS analysis of antioxidant plant phenoloids

Extracts of selected medicinal plants with promising integral antioxidative capacity were examined by high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD) and on-line mass spectrometry (ESI-MS or APCI-MS). These techniques allowed determination of the main components of each extract, which may serve us thereby providing a typical "finger-print" in the identification of the plants. More specifically various flavonol aglycones, flavon- and flavonol-glycosides, flavonoldiglycosides were detected in herbs of Solidago canadensis chemovarieties, in leaves of Filipendula ulmaria and in the herb of Viola tricolor species

Responsiveness of the widely used cardiomyocyte cell platforms to simulated ischemia/reperfusion

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research, Development and Innovation Office of Hungary (NKFIA; NVKP-16-1-2016-0017 National Heart Program and OTKA-FK 134751) MTA-SE System Pharmacology Research Group, Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary Ischemic heart disease is the leading cause of death worldwide; therefore, the development of cardioprotective therapies is currently a main focus of research. Cultured cell lines and primary cell cultures play an integral role in cardiovascular research. However, there are many limitations when using these models, including variations in proliferation capacity, uncontrolled stress during cell isolation, poor reproducibility and low translational value. The aim of our study was to test the responsiveness of the most widely used cardiomyocyte platforms to simulated ischemia/reperfusion injury (SI/R) considering the effect of differentiation protocols. Human, rat and mouse cell lines as well as primary cell cultures were used for in vitro viability assay with or without widely used differentiation protocols. The cells were exposed to normoxic or simulated ischemia/reperfusion protocols: a simulated ischemic period of 6 hours was used for the primary and the differentiated cell cultures, while for the non-differentiated cells 16 hours of simulated ischemia followed by 2 hours of reperfusion was applied. The duration of simulated ischemia was determined from preliminary experiments. Viability of the cells was measured by calcein assay. In non-differentiated human AC16 and rat H9C2 cardiac cell lines, cell viability was significantly reduced (50%) by 16h SI / 2h R in contrast, the viability of the mouse HL-1 cell line was not reduced by 16 h SI. In primary rat neonatal cardiac myocytes 6h SI / 2h R caused significant cell death (25%). In primary human iPSC-derived cardiac myocytes 6h SI / 2h R did not result significant injury (10%) whereas 16h did (37%). Responsiveness of different cell types to SI/R ranged between 40-100%. We have shown that the responsiveness of primary cardiac cells and non-differentiated cardiac cell lines is significantly different to simulated ischemia / reperfusion. Differentiation protocols in cell lines markedly affects their response to simulated ischemia / reperfusion. Comparative analyses of different types of cardiomyocytes can provide a good basis for accurate design of in vitro cardioprotective test systems. </jats:sec