Search results for "5(49)"
showing 10 items of 376 documents
Abstract 857: Metal oxide nanoparticles as adjuvant for radiation therapy
2018
Abstract Background: Radiation therapy comprises a fundamental component of modern tumor treatment. Unfortunately, its success is limited by the development of radiation resistances. The emerging field of nanotechnology offers great opportunities for diagnosing, imaging, as well as treating cancer. Metal oxide nanoparticles in particular zinc oxide nanoparticles (ZnO-NP) have been shown to display a selective cytotoxic effect on tumor cells via a yet unknown mechanism. Most likely the generation of reactive oxygen species (ROS), breakdown of mitochondria and DNA damage are involved. The success of radiation therapy equally relies on the generation of ROS, which develop their cytotoxic poten…
Surface plasmon resonance signal enhancement based on erlotinib loaded magnetic nanoparticles for evaluation of its interaction with human lung cance…
2021
Abstract Surface plasmon resonance (SPR) sensor provides a very useful tool based on its label-free, real-time monitoring and low price properties. However, measurement of small molecules and extremely diluted analytes is difficult and therefore, signal enhancement is required. In the present study, signal enhancement of erlotinib conjugated magnetic nanoparticles (erlotinib-MNPs) compared to erlotinib was evaluated via their interaction with overexpressed epidermal growth factor receptor on human lung cancer cells (A549 cell line) surface using SPR sensor at three temperature levels. The attained results showed an average signal amplification of about 2.5-fold for MNP-erlotinib interaction…
The combination of PDE4 and PDE5 inhibitors reduces YAP expression in IPF
2017
Background: Pathological fibrosis is associated with repeated episodes of injury to alveolar epithelial cells of largely. Yes-associated protein (YAP) is prominently expressed in fibrotic lung. Roflumilast has demonstrated to exhibit anti-fibrosis effects, while PDE5 inhibitors (sildenafil) combinated with PDE4 inhibitors reduce fibrotic-effects secondary to TGFs1. Apparently, no studies of PDE4 and PDE5 inhibitors on YAP expression there are. Objectives: To study the effects from adding a sildenafil to Roflumilast N- oxide (RNO) on TGF-β/SMAD3/YAP pathway in IPF in vitro models. Methods: A549 cells were pre-incubated with therapeutical concentrations of RNO (2nM) and/or sildenafil (10nM) a…
Microbiology and atmospheric processes: research challenges concerning the impact of airborne micro-organisms on the atmosphere and climate
2011
Cet article a fait l'objet d'une discussion dans "Morris, C. E., Sands, D. C., Bardin, M., Jaenicke, R., Vogel, B., Leyronas, C., Ariya, P. A., and Psenner, R.: Microbiology and atmospheric processes: an upcoming era of research on bio-meteorology, Biogeosciences Discuss., 5, 191-212, doi:10.5194/bgd-5-191-2008, 2008."; International audience; For the past 200 years, the field of aerobiology has explored the abundance, diversity, survival and transport of micro-organisms in the atmosphere. Micro-organisms have been explored as passive and severely stressed riders of atmospheric transport systems. Recently, an interest in the active roles of these micro-organisms has emerged along with prop…
The role of parasitism in adaptive radiations – when might parasites promote and when might they constrain ecological speciation?
2012
Research on speciation and adaptive radiation has flourished during the past decades, yet factors underlying initiation of reproductive isolation often remain unknown. Parasites represent important selective agents and have received renewed attention in speciation research. We review the literature on parasite-mediated divergent selection in context of ecological speciation and present empirical evidence for three nonexclusive mechanisms by which parasites might facilitate speciation: reduced viability or fecundity of immigrants and hybrids, assortative mating as a pleiotropic by-product of host adaptation, and ecologically-based sexual selection. We emphasise the lack of research on specia…
Humane Orientation as a New Cultural Dimension of the GLOBE Project: A Validation Study of the GLOBE Scale and Out-Group Humane Orientation in 25 Cou…
2013
SCHLÖSSER, Oliver; HEINTZE, Anna-Maria; AL-NAJJAR, Musaed; ARCISZEWSKI, Thomas; BESEVEGIS, Elias; BISHOP, George David; BONNES, Mirilia; CLEGG, Chris W.; DROZDA-SENKOWSKA, Ewa; GABORIT, Mauricio; GARZON, Dayra; HANSEN, Tia G. B.; HESZEN, Irena; JUHASZ, Marta; KEATING, Mary A.; MANGUNDJAYA, Wustari; MANSOR, Norma; MITCHELSON, Jacqueline K.; ORTIZ-REYNOSO, Alejandra; PANDEY, Janak; PAVAKANUN, Ubolwanna; PAVLOPOULOS, Vassilis; PEIRO, Jose M.; POTOCNIK, Kristina; RESTREPO-ESPINOSA, Maria H.; SEMMER, Norbert; TUPINAMBA, Antonio Caubi Ribeiro; VENTURA, Elizabeth R.; WHOOLERY, Matthew; ZHANG, Kan. Humane orientation as a new cultural dimension of the globe project: a validation study of the globe …
Loss of density-dependence and incomplete control by dominant breeders in a territorial species with density outbreaks
2011
Abstract Background A territory as a prerequisite for breeding limits the maximum number of breeders in a given area, and thus lowers the proportion of breeders if population size increases. However, some territorially breeding animals can have dramatic density fluctuations and little is known about the change from density-dependent processes to density-independence of breeding during a population increase or an outbreak. We suggest that territoriality, breeding suppression and its break-down can be understood with an incomplete-control model, developed for social breeders and social suppression. Results We studied density dependence in an arvicoline species, the bank vole, known as a terri…
Morphogenetic (Mucin Expression) as Well as Potential Anti-Corona Viral Activity of the Marine Secondary Metabolite Polyphosphate on A549 Cells
2020
The mucus layer of the nasopharynx and bronchial epithelium has a barrier function against inhaled pathogens such as the coronavirus SARS-CoV-2. We recently found that inorganic polyphosphate (polyP), a physiological, metabolic energy (ATP)-providing polymer released from blood platelets, blocks the binding of the receptor binding domain (RBD) to the cellular ACE2 receptor in vitro. PolyP is a marine natural product and is abundantly present in marine bacteria. Now, we have approached the in vivo situation by studying the effect of polyP on the human alveolar basal epithelial A549 cells in a mucus-like mucin environment. These cells express mucins as well as the ectoenzymes alkaline phospha…
The biocenotic value of Slitere National Park, Latvia, with special reference to inter-dune mires
2019
Inter-dune wetlands in Europe harbour many Red List species because they are very nutrient-poor ecosystems. Most of these wetlands are geologically very young and no or little peat formation has occurred. In Slītere National Park the numerous inter-dune wetlands are relatively old, up to 4500 years old, and most mire communities are peat forming and they are well preserved. However, the hydrological systems that have conserved the mires are largely unknown. In the present study we analysed 128 vegetation relevées of dune mires in order to assess the variation in ecological mire types. We also carried out several short-time studies to get an insight into the peat development and hydrological…
Chemical composition of modern and fossil hippopotamid teeth and implications for paleoenvironmental reconstructions and enamel formation – Part 2: A…
2012
Abstract. For reconstructing environmental change in terrestrial realms the geochemistry of fossil bioapatite in bones and teeth is among the most promising applications. This study demonstrates that alkaline earth elements in enamel of Hippopotamids, in particular Ba and Sr are tracers for water provenance and hydrochemistry. The studied specimens are molar teeth from Hippopotamids found in modern and fossil lacustrine settings of the Western Branch of the East African Rift system (Lake Kikorongo, Lake Albert, and Lake Malawi) and from modern fluvial environments of the Nile River. Concentrations in enamel vary by ca. two orders of magnitude for Ba (120–9336 μg g−1) as well as for Sr (9–21…