Search results for "dye"
showing 10 items of 577 documents
Next‐Generation Sequencing‐Based RiboMethSeq Protocol for Analysis of tRNA 2′‐O‐Methylation
2017
Analysis of RNA modifications by traditional physico‐chemical approaches is labor intensive, requires substantial amounts of input material and only allows site‐by‐site measurements. The recent development of qualitative and quantitative approaches based on next‐generation sequencing (NGS) opens new perspectives for the analysis of various cellular RNA species. The Illumina sequencing‐based RiboMethSeq protocol was initially developed and successfully applied for mapping of ribosomal RNA (rRNA) 2′‐O‐methylations. This method also gives excellent results in the quantitative analysis of rRNA modifications in different species and under varying growth condi…
Sodium functions as a negative allosteric modulator of the oxytocin receptor
2017
Abstract The oxytocin receptor, a class A G protein coupled receptor (GPCR), is essentially involved in the physiology of reproduction. Two parameters are crucially important to support high-affinity agonist binding of the receptor: Mg2+ and cholesterol, both acting as positive modulators. Using displacement assays with a high-affinity fluorescent antagonist (OTAN-A647), we now show that sodium functions as a negative allosteric modulator of the oxytocin receptor. In membranes from HEK293 cells stably expressing the oxytocin receptor, oxytocin binding occurred with about 15-fold lower affinity when sodium chloride was increased from 0 to 300 mM, whereas antagonist binding remained largely u…
Parthenolide and DMAPT exert cytotoxic effects on breast cancer stem-like cells by inducing oxidative stress, mitochondrial dysfunction and necrosis
2016
Triple-negative breast cancers (TNBCs) are aggressive forms of breast carcinoma associated with a high rate of recidivism. In this paper, we report the production of mammospheres from three lines of TNBC cells and demonstrate that both parthenolide (PN) and its soluble analog dimethylaminoparthenolide (DMAPT) suppressed this production and induced cytotoxic effects in breast cancer stem-like cells, derived from dissociation of mammospheres. In particular, the drugs exerted a remarkable inhibitory effect on viability of stem-like cells. Such an effect was suppressed by N-acetylcysteine, suggesting a role of reactive oxygen species (ROS) generation in the cytotoxic effect. Instead z-VAD, a ge…
Morpho-functional study of vascular fluorochrome delivery to lung and liver metastases of Lewis lung carcinoma (3LL).
1991
The growth of 3LL liver and lung metastases related to Its vascular organization was studied by morphological and functional methods, using the Hoechst 33342 fluorescent DNA staining technique. Experimental liver and lung metastases were produced in syngeneic C57BL/6 mice by injection of 3LL tumor cells into a lateral tail vein or into the spleen, respectively. The resulting neoplasms were composed of large cells arranged in sheets with a thin irregularly distributed stroma. Scattered blood vessels with an open or closed lumen were observed within the tumor. Functional study of H33342 diffusion showed a single and reticular fluorescent pattern in liver metastases. In contrast, in lung meta…
Autism Related Neuroligin-4 Knockout Impairs Intracortical Processing but not Sensory Inputs in Mouse Barrel Cortex
2016
Neuroligin-4 (Nlgn4) is a cell adhesion protein that regulates synapse organization and function. Mutations in human NLGN4 are among the causes of autism spectrum disorders. In mouse, Nlgn4 knockout (KO) perturbs GABAergic synaptic transmission and oscillatory activity in hippocampus, and causes social interaction deficits. The complex profile of cellular and circuit changes that are caused by Nlgn4-KO is still only partly understood. Using Nlgn4-KO mice, we found that Nlgn4-KO increases the power in the alpha frequency band of spontaneous network activity in the barrel cortex under urethane anesthesia in vivo. Nlgn4-KO did not affect single-whisker-induced local field potentials, but suppr…
Biofilm biodiversity in French and Swiss show caves using the metabarcoding approach: First data.
2018
International audience; In recent decades, show caves have begun to suffer from microorganism proliferation due to artificial lighting installations for touristic activity. In addition to the aesthetic problem, light encourages microorganisms that are responsible for physical and chemical degradation of limestone walls, speleothems and prehistoric paintings of cultural value. Microorganisms have previously been described by microscopy or culture-dependent methods, but data provided by new generation sequencing are rare. The authors identified, for the first time, microorganisms proliferating in one Swiss and in four French show caves using three different primers. The results showed that bo…
Easy One-Step Amplification and Labeling Procedure for Copy Number Variation Detection.
2019
Abstract Background The specific characteristics of copy number variations (CNVs) require specific methods of detection and characterization. We developed the Easy One-Step Amplification and Labeling procedure for CNV detection (EOSAL-CNV), a new method based on proportional amplification and labeling of amplicons in 1 PCR. Methods We used tailed primers for specific amplification and a pair of labeling probes (only 1 labeled) for amplification and labeling of all amplicons in just 1 reaction. Products were loaded directly onto a capillary DNA sequencer for fragment sizing and quantification. Data obtained could be analyzed by Microsoft Excel spreadsheet or EOSAL-CNV analysis software. We d…
Visualising G-quadruplex DNA dynamics in live cells by fluorescence lifetime imaging microscopy
2020
Guanine rich regions of oligonucleotides fold into quadruple-stranded structures called G-quadruplexes (G4s). Increasing evidence suggests that these G4 structures form in vivo and play a crucial role in cellular processes. However, their direct observation in live cells remains a challenge. Here we demonstrate that a fluorescent probe (DAOTA-M2) in conjunction with fluorescence lifetime imaging microscopy (FLIM) can identify G4s within nuclei of live and fixed cells. We present a FLIM-based cellular assay to study the interaction of non-fluorescent small molecules with G4s and apply it to a wide range of drug candidates. We also demonstrate that DAOTA-M2 can be used to study G4 stability i…
Direct observation of alpha-lactalbumin, adsorption and incorporation into lipid membrane and formation of lipid/protein hybrid structures
2019
The interaction between proteins and membranes is of great interest in biomedical and biotechnological research for its implication in many functional and dysfunctional processes. We present an experimental study on the interaction between model membranes and alpha-lactalbumin (alpha-La). alpha-La is widely studied for both its biological function and its anti-tumoral properties. We use advanced fluorescence microscopy and spectroscopy techniques to characterize alpha-La-membrane mechanisms of interaction and alpha-La-induced modifications of membranes when insertion of partially disordered regions of protein chains in the lipid bilayer is favored. Moreover, using fluorescence lifetime imag…
Old meets new: Comparative examination of conventional and innovative RNA-based methods for body fluid identification of laundered seminal fluid stai…
2018
Abstract The knowledge about the type of the body fluid/tissue that contributed to a trace can provide contextual insight into crime scene reconstruction and connect a suspect or a victim to a crime scene. Especially in sexual assault cases, it is important to verify the presence of spermatozoa. Victims often tend to clean their underwear/bedding after a sexual assault. If they later decide to report the crime to the police, in our experience, investigators usually do not send laundered items for DNA examination, since they believe that analysis after washing is no longer promising. As not only the individualization of traces on laundered items could be important in court, but also the type…