Search results for "Fluorescence"
showing 10 items of 2463 documents
Stretch-induced Intussuceptive and Sprouting Angiogenesis in the Chick Chorioallantoic Membrane
2014
Vascular systems grow and remodel in response to not only metabolic needs, but also mechanical influences as well. Here, we investigated the influence of tissue-level mechanical forces on the patterning and structure of the chick chorioallantoic membrane (CAM) microcirculation. A dipole stretch field was applied to the CAM using custom computer-controlled servomotors. The topography of the stretch field was mapped using finite element models. After 3 days of stretch, Sholl analysis of the CAM demonstrated a 7-fold increase in conducting vessel intersections within the stretch field (p 0.05). In contrast, corrosion casting and SEM of the stretch field capillary meshwork demonstrated intense …
In Toto Cell Tracking using Lightsheet Microscopy of the Neuromesodermal Progenitor Zone of the Zebrafish Tailbud from the 21st Somite Stage
2018
Lightsheet microscopy has been previously used to image and directly study the process of gastrulation in a zebrafish embryo. Before now it was not possible to use this method to study late-stage somatogenesis, due to the movement of the embryo, resulting in displacement from the field of view. Here we achieve 4D lightsheet imaging with online, image based registration to maintain the field of view during long timelapses, with emphasis on the tailbud. The zebrafish tailbud is of special interest as it contains a population of bipotent progenitor cells, neuromesodermal progenitors (NMps), competent to enter either the mesodermal or neural lineages. This dataset provides in toto tracking of t…
A Protein Nuclear Extract fromD. melanogasterLarval Tissues
2008
Preparation of protein nuclear extracts is often the first step to study in vitro biological processes occurring in the nucleus of the eukaryotic cell. Nuclear extracts have been extensively used in different model organisms to identify and study protein function in nuclei. Drosophila embryos can be collected in large quantities and have been the source of choice for the production of protein nuclear extracts. However, most of Drosophila in vivo studies on protein function are conducted in larval tissues. Here we report a new method to produce highly stable large-scale protein nuclear extracts from whole Drosophila larvae that are suited for a variety of biochemical analyses.
Oxidation Processes in Sicilian Olive Oils Investigated by a Combination of Optical and EPR Spectroscopy
2012
: Extra virgin olive oil (EVOO) is recognized as one of the healthiest foods for its high content of antioxidants, which forestall and slow down radical formation. Free radical-initiated oxidation is considered one of the main causes of rancidity in fats and oils. As a consequence, reliable protocols for the investigation of oil oxidation based on selective, noninvasive, and fast methods are highly desirable. Here we report an experimental approach based on UV-Vis absorbance, steady-state fluorescence, and electron paramagnetic resonance (EPR) spectroscopy for studying oxidation processes induced by temperature for a period up to 35 d on Sicilian EVOO samples. We followed the decrease in β…
Polycationic Monomeric and Homodimeric Asymmetric Monomethine Cyanine Dyes with Hydroxypropyl Functionality—Strong Affinity Nucleic Acids Binders
2021
New analogs of the commercial asymmetric monomethine cyanine dyes thiazole orange (TO) and thiazole orange homodimer (TOTO) with hydroxypropyl functionality were synthesized and their properties in the presence of different nucleic acids were studied. The novel compounds showed strong, micromolar and submicromolar affinities to all examined DNA ds-polynucleotides and poly rA–poly rU. The compounds studied showed selectivity towards GC-DNA base pairs over AT-DNA, which included both binding affinity and a strong fluorescence response. CD titrations showed aggregation along the polynucleotide with well-defined supramolecular chirality. The single dipyridinium-bridged dimer showed intercalatio…
Fluorescence enhancement of quinolines by protonation.
2020
A study of the fluorescence enhancement of isoquinoline, acridine (benzo[b]quinoline) and benzo[h]quinoline is reported with six organic acids of different pKa values. Protonation was found to be an effective tool in the fluorescence enhancement of quinolines. A significant increase in the fluorescence intensity is observed only when strong acids are used, resulting in an over 50-fold increase in fluorescence with trifluoroacetic or benzenesulfonic acid and isoquinoline in a 1.5 : 1 ratio. The benzenesulfonic acid was found to be the most effective in the protonation of the bases despite its higher pKa value compared to trifluoro- and trichloroacetic acid. The X-ray crystal structures of 14…
Nonlinear optical properties of diaromatic stilbene, butadiene and thiophene derivatives
2021
Series of highly polar stilbene (1a–e), diphenylbutadiene (2a–c) and phenylethenylthiophene (3a–c) derivatives were prepared via Horner–Wadsworth–Emmons method with a view to produce new and efficient materials for second harmonic generation (SHG) in the solid-state. The single-crystal X-ray structures of compounds 1–3 reveal extensive polymorphism and a peculiar photodimerization of the 2-chloro-3,4-dimethoxy-4′-nitrostilbene derivative 1a to afford two polymorphs of tetra-aryl cyclobutane 4. The stilbene congeners 2-chloro-3,4-dimethoxy-4′-nitrostilbene (1a·non-centro), 5-bromo-2-hydroxy-3-nitro-4′-nitrostilbene (1b) and 4-dimethylamino-4′-nitrostilbene (1e), as well as 4′-fluoro-4′′-nitr…
Non-structural proteins P17 and P33 are involved in the assembly of the internal membrane-containing virus PRD1.
2015
AbstractBacteriophage PRD1, which has been studied intensively at the structural and functional levels, still has some gene products with unknown functions and certain aspects of the PRD1 assembly process have remained unsolved. In this study, we demonstrate that the phage-encoded non-structural proteins P17 and P33, either individually or together, complement the defect in a temperature-sensitive GroES mutant of Escherichia coli for host growth and PRD1 propagation. Confocal microscopy of fluorescent fusion proteins revealed co-localisation between P33 and P17 as well as between P33 and the host chaperonin GroEL. A fluorescence recovery after photobleaching assay demonstrated that the diff…
Streptococcus pneumoniae sortāzes A inhibitoru atlase multirezistentu patogēnu izraisīto infekcijas slimību terapijai
2019
Darba mērķis ir atrast jaunas novatoriskas vielas, kas inhibē Grampozitīvās baktērijas Streptococcus pneumoniae transpeptidāzi sortāzi A. Šo inhibitoru atlasei tika izmantota rekombinanta S.pneumoniae sortāzes A katalītisko domēnu kodējoša konstrukcija bez N terminālā reģiona. Šāda rekombinanta transpeptidāze tika ekspresēta E.coli ekspresijas sistēmā un sintezētais proteīns izrādījās šķīstošs. Pēc attīrīšanas sortāze tika izmantota inhibitoru atlasei, izmantojot skrīningu, kas balstās uz fluorescences rezonanses enerģijas pārnesi (FRET). Pavisam tika pārbaudīti 966 potenciāli inhibitori savienojumi, no kuriem tālākām pārbaudēm tika atlasīti trīs labākie, kuri inhibēja IC50 testā izmantotās…
FISH mapping of 18S rDNA and (TTAGGG)n sequences in two pipefish species (Gasteroisteiformes: Syngnathidae).
2006
1Istituto di Scienze Marine, Sezione di Venezia, CNR, Castello 1364/a, 30122 Venezia, Italy 2Dipartimento di Biologia Animale, Universita di Palermo, Via Archirafi 18, 90123 Palermo, Italy 3Dipartimento di Scienze Ambientali, Universita “Ca’ Foscari”, Castello 2737/b 30122 Venezia, Italy 4Istituto di Ecologia e Biologia Ambientale, Universita di Urbino “Carlo Bo”, Via I. Maggetti 22, 61029 Urbino (PU), Italy