Search results for "Model system"
showing 10 items of 55 documents
Microbial interactions in food model systems: In situ antilisterial activity of mundticin KS producing strains
2013
It is known that microbial interactions are important for the success of food fermentations, as well as for the establishment of the safety of the final products. In this study, we characterized extensively three enterococci (WFE3, WFE20 and WFE31) of flour origin, which were found to be active against Listeria monocytogenes, in order to investigate on their ability to produce bacteriocins in complex food model systems for their future industrial/food applications. The identification of the three bacterial isolates was performed by means of a combined 16S rRNA gene sequencing and multiplex PCR approach. Two isolates belonged unequivocally to the species E. mundtii, while one isolate could n…
Positioning Europe for the EPITRANSCRIPTOMICS challenge
2018
WOS: 000444092300018 PubMed ID: 29671387 The genetic alphabet consists of the four letters: C, A, G, and T in DNA and C,A,G, and U in RNA. Triplets of these four letters jointly encode 20 different amino acids out of which proteins of all organisms are built. This system is universal and is found in all kingdoms of life. However, bases in DNA and RNA can be chemically modified. In DNA, around 10 different modifications are known, and those have been studied intensively over the past 20years. Scientific studies on DNA modifications and proteins that recognize them gave rise to the large field of epigenetic and epigenomic research. The outcome of this intense research field is the discovery t…
Antiviral activity of aged green tea extract in model food systems and under gastric conditions.
2018
Aged-green tea extract (GTE) is known to reduce the infectivity of hepatitis A virus (HAV) and murine norovirus (MNV), a human norovirus surrogate, in vitro and in washing solutions. Initially, the effect of aged-GTE was evaluated on virus like particles (VLPs) of human norovirus (HuNoV) genogroup I (GI) by a porcine gastric mucine (PGM)-enzyme-linked immunosorbent assay (ELISA) and transmission electron microscopy (TEM), and on HuNoV GI suspensions by an in situ capture-RT-qPCR method, suggesting that HuNoVs are very sensitive to aged-GTE treatment at 37 °C. Moreover, the potential application of aged-GTE was evaluated using model foods and simulated gastric conditions. Then, aged-GTE samp…
Drosophila as a Model System for the Identification of Pharmacological Therapies in Neurodegenerative Diseases
2019
Neurodegenerative diseases (NDs) constitute a very important problem in our current society, as they are usually associated with the aging process. NDs are devastating disorders that lead to severe disabilities and ultimately to death and have a considerable impact on human health. Although intense efforts are being made to shed light on the pathophysiology underlying these diseases, an important concern is that NDs are incurable and existing therapies are only directed to relieve their symptoms or delay the progression of the disease. Therefore, the development of new therapeutic approaches against NDs is urgent and challenging. In such a scenario, Drosophila is a very valuable model organ…
7-Ketocholesterol as marker of cholesterol oxidation in model and food systems: when and how.
2014
Cholesterol can undergo oxidation through enzymatic or chemical mechanisms, generating a wide range of oxidation products (COPs) with adverse biological effects. COPs are characterized by different functional groups and are produced in different ratios or amounts, depending on the treatment and storage conditions. To follow the cholesterol oxidation process, 7-ketocholesterol (7-KC) has been often used as an oxidation marker in both model and food systems, since it is easily formed and is one of the most representative ring COPs. However, 7-KC does not always rise with increasing time/temperature conditions, especially in complex systems and high-protein or extensively processed foods. The …
On the relationship between knowledge creation and economic performance
2015
An empirical two-equation dynamic panel-data model system with fixed effects is proposed to analyze the relationship between knowledge creation and economic performance across regions over time. Estimates of the model for Spanish regions show that (i) knowledge creation depends on local R&D effort, on the amount of knowledge in use, and on knowledge creation in neighboring regions; and (ii) assimilation of new knowledge depends on local knowledge creation and on assimilation of knowledge in neighboring regions. Both processes include region-specific context fixed effects and region-specific time effects, representing region-specific dynamic influences. The results imply that (a) efficie…
Fluorescence Microscopy Studies of Structure Formation in Surfactant Monolayers
1993
Monolayers of water-insoluble surfactants (Langmuir monolayers) are important model system in basic research for studying the self-organization of organic molecules into two-dimensional layers [1, 2]. These floating films are also the basis for the build-up of complex multilayered structures on solid substrates, so-called Langmuir—Blodgett films (LB-films), which are of considerable interest in fundamental science and promise some future practical applications [3].
Drastic Variation of the Microstructure Formation in a Charged Sphere Colloidal Model System by Adding Merely Tiny Amounts of Larger Particles
2010
We have investigated the changes of the crystallization scenario in charged sphere colloidal suspensions upon adding tiny amounts of a second, larger and higher charged particle species (size ratio 4.3, charge ratio 1.6). For even minute amounts of added particles, less than 1%, the whole crystallization behavior changes dramatically and for this reason the resulting microstructure of the solidified material. Both nucleation and growth of crystals slow down drastically and considerably coarsen the resulting microstructure. We show that this is related to a considerable decrease of the kinetic prefactors of both nucleation and growth, while at the same time the nucleation barrier height show…
On the Shape-Selected, Ligand-Free Preparation of Hybrid Perovskite (CH3NH3PbBr3) Microcrystals and Their Suitability as Model-System for Single-Crys…
2021
Hybrid perovskite materials are one of the most promising candidates for optoelectronic applications, e.g., solar cells and LEDs, which can be produced at low cost compared to established materials. Although this field of research has seen a huge upsurge in the past decade, there is a major lack in understanding the underlying processes, such as shape-property relationships and the role of defects. Our aerosol-assisted synthesis pathway offers the possibility to obtain methylammonium lead bromide (MAPbBr3 ) microcrystals from a liquid single source precursor. The differently shaped particles are aligned on several substrates, without using a directing agent or other additives. The obtained …
Probing in cell protein structural changes with time-resolved X-ray scattering
2012
International audience; Investigating protein structural changes inside the cell is a major goal in molecular biology. Here we show that time-resolved wide-angle X-ray scattering is a valuable tool for this purpose. Hemoglobin has been chosen as a model system and its tertiary and quaternary conformational changes following laser flash-photolysis have been tracked in intact red blood cells with nanosecond time resolution.