Search results for "fluorescent"

A new simple chromo-fluorogenic probe for NO2 detection in air.

2015

[EN] A new chromo-fluorogenic probe, consisting of a biphenyl derivative containing both a silylbenzyl ether and a N,N-dimethylamino group, for NO2 detection in the gas phase has been developed. A clear colour change from colourless to yellow together with an emission quenching was observed when the probe reacted with NO2. A limit of detection to the naked eye of about 0.1 ppm was determined and the system was successfully applied to the detection of NO2 in realistic atmospheric conditions.

Iron Induces Proliferation and Morphogenesis in Primmorphs from the Marine SpongeSuberites domuncula

2002

Dissociated cells from marine demosponges retain their proliferation capacity if they are allowed to form special aggregates, the primmorphs. On the basis of incorporation studies and septin gene expression, we show that Fe3+ ions are required for the proliferation of cells in primmorphs from Suberites domuncula. In parallel, Fe3+ induced the expression of ferritin and strongly stimulated the synthesis of spicules. This result is supported by the finding that the enzymatic activity of silicatein, converting organosilicon to silicic acid, depends on Fe3+. Moreover, the expression of a scavenger receptor molecule, possibly involved in the morphology of spicules, depends on the presence of Fe3…

Facile Synthesis of Fluorescent Polymer Nanoparticles by Covalent Modification-Nanoprecipitation of Amine-Reactive Ester Polymers

2015

Emission wavelength control in fluorescent nanoparticles (NPs) is crucial for their applications. In the case of inorganic quantum dots or dye-impregnated silica NPs, such a control is readily achieved by changing the size of the particles or choosing appropriate fluorescent dyes, respectively. A similar modular approach for controlling the emission wavelength of fluo-rescent polymer NPs, however, is difficult. This article reports on fluorescent polymer NPs, the synthesis of which provides a platform for a modular approach towards the preparation of fluorescent NPs of desired emission wavelength. Atom-transfer radical polymerization (ATRP) is employed to synthesize reactive ester polymers,…

Optimizing the SYBR green related cyanine dye structure to aim for brighter nucleic acid visualization

2022

In recent years, the studies of RNA and its use for the development of RNA based vaccines have increased drastically. Although cyanine dyes are commonly used probes for studying nucleic acids, in a wide range of applications, there is still a growing need for better and brighter dyes. To meet this demand, we have systematically studied the structure of SYBR green-related cyanine dyes to gain a deeper understanding of their interactions with biomolecules especially how they interact with nucleic acids and the structural components which makes them strongly fluorescent. Herein, five new dyes were synthesized, and their photophysical properties were evaluated. Observations of photophysical cha…

Intranuclear dynamics in parvovirus infection

2009

N-galā ieviestas hemaglutinīna iezīmes ietekme uz melanokortīnu receptoru daudzumu šūnas membrānā

2018

Darbā tika veikta ar hemaglutinīna (HA) iezīmi N-galā un zaļo fluorescento proteīnu (GFP) C- galā sajūgtu melanokortīna 2. tipa (MC2R) un 4. tipa (MC4R) sekvenču kodējošu ekspresijas plazmīdu izveide. Jauniegūtajiem receptoriem tika noteikta funkcionālā aktivitāte CHO (Chinese Hamster Ovary cells) šūnās, lai pārliecinātos par to atbilstību izmantošanai receptoru šūnu virsmas ekspresijas mērījumos. Darba mērķis bija izmantot šos receptorus, lai pārbaudītu HA iezīmes un GFP ietekmi uz receptoru CHO virsmas ekspresiju, izmantojot konfokālo lāzerskenējošo mikroskopiju un imunofluorescento testu attiecīgi. Darbā tehnisku sarežģījumu dēļ netika pārbaudīta GFP ietekme, bet novērotā HA ietekme mazi…

Localization of GFP-Tagged Proteins at the Electron Microscope

2016

B lymphocyte intestinal homing in inflammatory bowel disease.

2011

Abstract Background Inflammatory bowel disease (IBD) is thought to be due to an abnormal interaction between the host immune system and commensal microflora. Within the intestinal immune system, B cells produce physiologically natural antibodies but pathologically atypical anti-neutrophil antibodies (xANCAs) are frequently observed in patients with IBD. The objective is to investigate the localisation of immunoglobulin-producing cells (IPCs) in samples of inflamed intestinal tissue taken from patients with IBD, and their possible relationship with clinical features. Methods The IPCs in small intestinal, colonic and rectal biopsy specimens of patients with IBD were analysed by means of immun…

Reductive modification of genetically encoded 3-nitrotyrosine sites in alpha synuclein expressed in E.coli

2019

Tyrosine nitration is a post-translational protein modification relevant to various pathophysiological processes. Chemical nitration procedures have been used to generate and study nitrated proteins, but these methods regularly lead to modifications at other amino acid residues. A novel strategy employs a genetic code modification that allows incorporation of 3-nitrotyrosine (3-NT) during ribosomal protein synthesis to generate a recombinant protein with defined 3-NT-sites, in the absence of other post-translational modifications. This approach was applied to study the generation and stability of the 3-NT moiety in recombinant proteins produced in E.coli. Nitrated alpha-synuclein (ASYN) was…

Design, Synthesis and Characterization of a Visible-Light-Sensitive Molecular Switch and Its PEGylation Towards a Self-Assembling Molecule.

2022

HBDI-like chromophores represent a novel set of biomimetic switches mimicking the fluorophore of the green fluorescent protein that are currently studied with the hope to expand the molecular switch/motor toolbox. However, until now members capable of absorbing visible light in their neutral (i. e. non-anionic) form have not been reported. In this contribution we report the preparation of an HBDI-like chromophore based on a 3-phenylbenzofulvene scaffold capable of absorbing blue light and photoisomerizing on the picosecond timescale. More specifically, we show that double-bond photoisomerization occurs in both the E-to-Z and Z-to-E directions and that these can be controlled by irradiating …