Search results for "DEP"
showing 10 items of 10555 documents
Bioelectrical coupling in multicellular domains regulated by gap junctions: A conceptual approach.
2018
We review the basic concepts involved in bioelectrically-coupled multicellular domains, focusing on the role of membrane potentials (Vmem). In the first model, single-cell Vmem is modulated by two generic polarizing and depolarizing ion channels, while intercellular coupling is implemented via voltage-gated gap junctions. Biochemical and bioelectrical signals are integrated via a feedback loop between Vmem and the transcription and translation of a protein forming an ion channel. The effective rate constants depend on the single-cell Vmem because these potentials modulate the local concentrations of signaling molecules and ions. This electrochemically-based idealization of the complex bioph…
Intercellular Connectivity and Multicellular Bioelectric Oscillations in Nonexcitable Cells: A Biophysical Model
2018
Bioelectricity is emerging as a crucial mechanism for signal transmission and processing from the single-cell level to multicellular domains. We explore theoretically the oscillatory dynamics that result from the coupling between the genetic and bioelectric descriptions of nonexcitable cells in multicellular ensembles, connecting the genetic prepatterns defined over the ensemble with the resulting spatio-temporal map of cell potentials. These prepatterns assume the existence of a small patch in the ensemble with locally low values of the genetic rate constants that produce a specific ion channel protein whose conductance promotes the cell-polarized state (inward-rectifying channel). In this…
Managing adult patients with infectious diseases in emergency departments: international ID-IRI study.
2021
We aimed to explore factors for optimizing antimicrobial treatment in emergency departments. A single-day point prevalence survey was conducted on January 18, 2020, in 53 referral/tertiary hospitals in 22 countries. 1957 (17%) of 11557 patients presenting to EDs had infections. The mean qSOFA score was 0.37 +/- 0.74. Sepsis (qSOFA >= 2) was recorded in 218 (11.1%) patients. The mean qSOFA score was significantly higher in low-middle (1.48 +/- 0.963) compared to upper-middle (0.17 +/- 0.482) and high-income (0.36 +/- 0.714) countries ( P < 0.001). Eight (3.7%) patients with sepsis were treated as outpatients. The most common diagnoses were upper-respiratory (n = 877, 43.3%), lower-respirator…
Chemical probes to potently and selectively inhibit endocannabinoid cellular reuptake
2017
The extracellular effects of the endocannabinoids anandamide and 2-arachidonoyl glycerol are terminated by enzymatic hydrolysis after crossing cellular membranes by facilitated diffusion. The lack of potent and selective inhibitors for endocannabinoid transport has prevented the molecular characterization of this process, thus hindering its biochemical investigation and pharmacological exploitation. Here, we report the design, chemical synthesis, and biological profiling of natural product-derived N-substituted 2,4-dodecadienamides as a selective endocannabinoid uptake inhibitor. The highly potent (IC50 = 10 nM) inhibitor N-(3,4-dimethoxyphenyl)ethyl amide (WOBE437) exerted pronounced canna…
Microbiome restoration diet improves digestion, cognition and physical and emotional wellbeing
2017
Manipulating gut bacteria in the microbiome, through the use of probiotics and prebiotics, has been found to have an influence on both physical and emotional wellbeing. This study uses a dietary manipulation 'The Gut Makeover' designed to elicit positive changes to the gut bacteria within the microbiome. 21 healthy participants undertook 'The Gut Makeover' for a four week period. Weight and various aspects of health were assessed pre and post intervention using the Functional Medicine Medical Symptoms Questionnaire (MSQ). Paired sample t-tests revealed a significant reduction in self-reported weight at the end of the intervention. Adverse medical symptoms related to digestion, cognition and…
A systematic variant screening in familial cases of congenital heart defects demonstrates the usefulness of molecular genetics in this field
2016
International audience; The etiology of congenital heart defect (CHD) combines environmental and genetic factors. So far, there were studies reporting on the screening of a single gene on unselected CHD or on familial cases selected for specific CHD types. Our goal was to systematically screen a proband of familial cases of CHD on a set of genetic tests to evaluate the prevalence of disease-causing variant identification. A systematic screening of GATA4, NKX2-5, ZIC3 and Multiplex ligation-dependent probe amplification (MLPA) P311 Kit was setup on the proband of 154 families with at least two cases of non-syndromic CHD. Additionally, ELN screening was performed on families with supravalvula…
Transcriptomic study of the toxic mechanism triggered by beauvericin in Jurkat cells
2018
Beauvericin (BEA), an ionophoric cyclic hexadepsipeptide mycotoxin, is able to increase oxidative stress by altering membrane ion permeability and uncoupling oxidative phosphorylation. A toxicogenomic study was performed to investigate gene expression changes triggered by BEA exposure (1.5, 3 and 5 mu M; 24 h) in Jurkat cells through RNA-sequencing and differential gene expression analysis. Perturbed gene expression was observed in a concentration dependent manner, with 43 differentially expressed genes (DEGs) overlapped in the three studied concentrations. Gene ontology (GO) analysis showed several biological processes related to electron transport chain, oxidative phosphorylation, and cel…
Mechanisms of beauvericin toxicity and antioxidant cellular defense
2015
Beauvericin (BEA) is a secondary metabolite produced by many species of fungus Fusarium. This study determines the injury (cell viability, cell proliferation, mitochondrial membrane potential, cell death and DNA damage) and the intracellular defense mechanisms (catalase and superoxide dismutase) in Chinese Hamster ovary (CHO-K1) cells after BEA exposure. The results obtained in this study demonstrated that BEA induces cytotoxicity in a dose- and time-dependent manner in CHO-K1 cells. Moreover, disruption in mitochondrial enzymatic activity and cell proliferation has been observed after BEA exposure, which can lead or be consequence of cell death. BEA inhibits cell proliferation by arresting…
Neurotoxicity of zearalenone’s metabolites and beauvericin mycotoxins via apoptosis and cell cycle disruption
2021
Cell cycle progression and programmed cell death are imposed by pathological stimuli of extrinsic or intrinsic including the exposure to neurotoxins, oxidative stress and DNA damage. All can cause abrupt or delayed cell death, inactivate normal cell survival or cell death networks. Nevertheless, the mechanisms of the neuronal cell death are unresolved. One of the cell deaths triggers which have been wildly studied, correspond to mycotoxins produced by Fusarium species, which have been demonstrated cytotoxicity and neurotoxicity through impairing cell proliferation, gene expression and induction of oxidative stress. The aim of present study was to analyze the cell cycle progression and cell …
Aβ Induces Excitotoxicity Mediated by APC/C-Cdh1 Depletion That Can Be Prevented by Glutaminase Inhibition Promoting Neuronal Survival
2016
AbstractThe E3 ubiquitin ligase anaphase-promoting complex/cyclosome (APC/C) is activated by the fizzy-related protein homolog/CDC20-like protein 1 (cdh1) in post-mitotic neurons. Growing evidence suggests that dysregulation of APC/C-Cdh1 is involved in neurodegenerative diseases. Here we show in neurons that oligomers of amyloid beta (Aβ), a peptide related to Alzheimer’s disease, cause proteasome-dependent degradation of cdh1. This leads to a subsequent increase in glutaminase (a degradation target of APC/C-Cdh1), which causes an elevation of glutamate levels and further intraneuronal Ca2+ dysregulation, resulting in neuronal apoptosis. Glutaminase inhibition prevents glutamate excitotoxi…