Search results for "nuclei"

Experimental and theoretical characterization of the strong effects on DNA stability caused by half-sandwich Ru(II) and Ir(III) bearing thiabendazole…

2020

Abstract: The synthesis and characterization of two half-sandwich complexes of Ru(II) and Ir(III) with thiabendazole as ancillary ligand and their DNA binding ability were investigated using experimental and computational methods. 1H NMR and acid–base studies have shown that aquo-complexes are the reactive species. Kinetic studies show that both complexes bind covalently to DNA through the metal site and non covalently through the ancillary ligand. Thermal stability studies, viscosity, circular dichroism measurements and quantum chemical calculations have shown that the covalent binding causes breaking of the H-bonding between base pairs, bringing about DNA denaturation and compaction. Addi…

Forever Young: Structural Stability of Telomeric Guanine Quadruplexes in the Presence of Oxidative DNA Lesions**

2021

International audience; Human telomeric DNA, in G-quadruplex (G4) conformation, is characterized by a remarkable structural stability that confers it the capacity to resist to oxidative stress producing one or even clustered 8-oxoguanine (8oxoG) lesions. We present a combined experimental/computational investigation, by using circular dichroism in aqueous solutions, cellular immunofluorescence assays and molecular dynamics simulations, that identifies the crucial role of the stability of G4s to oxidative lesions, related also to their biological role as inhibitors of telomerase, an enzyme overexpressed in most cancers associated to oxidative stress.

Possible relationship between micronucleated and binucleated cells induced by cisplatin in cultured CHO cells

1993

Abstract Chinese hamster ovary (CHO) cells were treated with a single dose (10 μg/ml) of cis-diammino-dichloroplatinum (II) (cisplatin) for 1 h and the effect of the drug on the kinetics of proliferation of the cultures was studied. It was found that the drug produces a delay in the proliferation rates of the treated cultures. The induction of micronuclei and binucleated cells (BC) at different times after treatment have also been studied, and the ability of these cells to undergo DNA synthesis (measured as the ability to incorporate [3H]thymidine) is shown. It was found that cisplatin induced a particular type of BC that contains one or more micronuclei rather than a pure population of BC.…

Cloning and sequencing of the chicken egg-white avidin-encoding gene and its relationship with the avidin-related genes Avrl-Avr5

1995

Abstract The gene encoding chicken egg-white avidin (Avd) was amplified from chromosomal DNA, cloned and sequenced. The entire coding region of preavidin (pre-Avd) containing four exons was identified by comparing the Avd gene (1119 bp) with the cDNA. It had a high identity percentage (91–95%) with the previously isolated Avd-related genes 1–5 (Avrl–Avr5) . Interestingly, comparison of Avd with the Avr genes showed that the introns were better conserved (on average 97%) than the exons (90%). The Avd gene, as well as the cDNA, encodes a Gln residue at position 53 of the mature protein, which is in contrast to the previously determined amino-acid sequence.

Nucleotide sequence of Clostridium difficile toxin A.

1990

Linear relationship between effective radius and precipitation water content near the top of convective clouds

2021

Quantifying the precipitation within clouds is a crucial challenge to improve our current understanding of the Earth’s hydrological cycle. We have investigated the relationship between the effective radius of droplets and ice particles (re) and precipitation water content (PWC) measured by cloud probes near the top of growing convective cumuli. The data for this study were collected by aircraft measurements in clean and polluted conditions over the Amazon Basin and over the western tropical Atlantic in September 2014. Our results indicate a threshold of re ∼ 13 μm for warm rain initiation in convective clouds, which is in agreement with previous studies. In…

Thalamic Network Oscillations Synchronize Ontogenetic Columns in the Newborn Rat Barrel Cortex

2013

Neocortical areas are organized in columns, which form the basic structural and functional modules of intracortical information processing. Using voltage-sensitive dye imaging and simultaneous multi-channel extracellular recordings in the barrel cortex of newborn rats in vivo, we found that spontaneously occurring and whisker stimulation-induced gamma bursts followed by longer lasting spindle bursts were topographically organized in functional cortical columns already at the day of birth. Gamma bursts synchronized a cortical network of 300-400 µm in diameter and were coherent with gamma activity recorded simultaneously in the thalamic ventral posterior medial (VPM) nucleus. Cortical gamma b…

Small-molecule affinity capture of DNA/RNA quadruplexes and their identification in vitro and in vivo through the G4RP protocol

2019

International audience; Guanine-rich DNA and RNA sequences can fold into higher-order structures known as G-quadruplexes (or G4-DNA and G4-RNA, respectively). The prevalence of the G4 landscapes in the human genome, transcriptome and ncRNAome (non-coding RNA), collectively known as G4ome, is strongly suggestive of biological relevance at multiple levels (gene expression , replication). Small-molecules can be used to track G4s in living cells for the functional characterization of G4s in both normal and disease-associated changes in cell biology. Here, we describe biotinylated biomimetic ligands referred to as Bio-TASQ and their use as molecular tools that allow for isolating G4s through aff…

JANE: efficient mapping of prokaryotic ESTs and variable length sequence reads on related template genomes

2009

Abstract Background ESTs or variable sequence reads can be available in prokaryotic studies well before a complete genome is known. Use cases include (i) transcriptome studies or (ii) single cell sequencing of bacteria. Without suitable software their further analysis and mapping would have to await finalization of the corresponding genome. Results The tool JANE rapidly maps ESTs or variable sequence reads in prokaryotic sequencing and transcriptome efforts to related template genomes. It provides an easy-to-use graphics interface for information retrieval and a toolkit for EST or nucleotide sequence function prediction. Furthermore, we developed for rapid mapping an enhanced sequence align…

Dorsal Column Nuclei Neural Signal Features Permit Robust Machine-Learning of Natural Tactile- and Proprioception-Dominated Stimuli

2020

Neural prostheses enable users to effect movement through a variety of actuators by translating brain signals into movement control signals. However, to achieve more natural limb movements from these devices, the restoration of somatosensory feedback is required. We used feature-learnability, a machine-learning approach, to assess signal features for their capacity to enhance decoding performance of neural signals evoked by natural tactile and proprioceptive somatosensory stimuli, recorded from the surface of the dorsal column nuclei (DCN) in urethane-anesthetized rats. The highest performing individual feature, spike amplitude, classified somatosensory DCN signals with 70% accuracy. The hi…