Search results for "Potassium"

Antibiotic prescription for the prevention and treatment of postoperative complications after routine dental implant placement. A cross-sectional stu…

2018

Background As there are no established guidelines for antibiotic prescription after dental implant placement a study was made to determine the current prescribing habits of several groups of practitioners regarding antibiotics to prevent and/or treat postoperative complications - early failures and infections - in relation to routine dental implant placement. Material and methods An electronic survey was sent to postgraduate students and professionals with experience in routine dental implant placement who practice in Spain. The questions asked were related to whether antibiotics were routinely prescribed either pre- or postoperatively to prevent and/or treat postoperative complications dur…

Oligodendrocytes control potassium accumulation in white matter and seizure susceptibility

2018

Oligodendrocytes Control Potassium Accumulation in White Matter and Seizure Susceptibility.Larson VA, Mironova Y, Vanderpool KG, Waisman A, Rash JE, Agarwal A, Bergles DE. Elife. 2018 Mar 29;7. pii: e34829. doi: 10.7554/eLife.34829.The inwardly rectifying K+ channel Kir4.1 is broadly expressed by central nervous system glia and deficits in Kir4.1 lead to seizures and myelin vacuolization. However, the role of oligodendrocyte Kir4.1 channels in controlling myelination and K+ clearance in white matter has not been defined. Here, we show that selective deletion of Kir4.1 from oligodendrocyte progenitors or mature oligodendrocytes did not impair their development or disrupt the structure of mye…

Molecular mechanisms underlying the neuroprotective role of atrial natriuretic peptide in experimental acute ischemic stroke

2018

Abstract Along with its role in regulating blood pressure and fluid homeostasis, the natriuretic peptide system could be also part of an endogenous protective mechanism against brain damage. We aimed to assess the possibility that exogenous atrial natriuretic peptide (ANP) could protect against acute ischemic stroke, as well as the molecular mechanisms involved. Three groups of rats subjected to transient middle cerebral artery occlusion (tMCAO, intraluminal filament technique, 60 min) received intracerebroventricular vehicle, low-dose ANP (0.5 nmol) or high-dose ANP (2.5 nmol), at 30 min reperfusion. Neurofunctional condition, and brain infarct and edema volumes were measured at 24 h after…

A role for TASK2 channels in the human immunological synapse.

2020

The immunological synapse is a transient junction that occurs when the plasma membrane of a T cell comes in close contact with an APC after recognizing a peptide from the antigen-MHC. The interaction starts when CRAC channels embedded in the T cell membrane open, flowing calcium ions into the cell. To counterbalance the ion influx and subsequent depolarization, Kv 1.3 and KCa3.1 channels are recruited to the immunological synapse, increasing the extracellular K+ concentration. These processes are crucial as they initiate gene expression that drives T cell activation and proliferation. The T cell-specific function of the K2P channel family member TASK2 channels and their role in autoimmune p…

Prenatal exposure to mixtures of xenoestrogens and genome-wide DNA methylation in human placenta

2015

BACKGROUND: In utero exposure to xenostrogens may modify the epigenome. We explored the association of prenatal exposure to mixtures of xenoestrogens and genome-wide placental DNA methylation. MATERIALS & METHODS: Sex-specific associations between methylation changes in placental DNA by doubling the concentration of TEXB-alpha exposure were evaluated by robust multiple linear regression. Two CpG sites were selected for validation and replication in additional male born placentas. RESULTS: No significant associations were found, although the top significant CpGs in boys were located in the LRPAP1, HAGH, PPARGC1B, KCNQ1 and KCNQ1DN genes, previously associated to birth weight, Type 2 diabetes…

Efficacy and tolerability of switching to a dual therapy with darunavir/ritonavir plus raltegravir in HIV-infected patients with HIV-1 RNA ≤50 cp/…

2017

Background: Nucleos(t)ide reverse transcriptase inhibitors (NRTI) toxicity may represent a threat for long-term success of combined antiretroviral therapy. Some studies have suggested a possible improvement of NRTI-related toxicity after switching to NRTI-sparing regimens. Objectives: We aimed to explore the efficacy and tolerability of switching to darunavir/ritonavir (DRV/r) plus raltegravir (RAL) while having a viral load (VL) ≤50 copies/mL in the clinical setting. Study design: Treatment-experienced HIV 1-infected patients enrolled in the ICONA Foundation Study cohort were included if they switched their current regimen to DRV/r + RAL with a HIV-RNA ≤50 copies/mL. Different defin…

Mechanisms involved in the increased sensitivity of the rabbit basilar artery to atrial natriuretic peptide in diabetes.

2017

Atrial natriuretic peptide (ANP) is a vasodilator with significant regional differences and controversial effects in the cerebral circulation, a vascular bed particularly prone to diabetes-induced complications. The present study has investigated how alloxan-induced diabetes modifies the mechanisms involved in the response of the rabbit basilar artery to ANP. ANP (10(-12) -10(-7) M) relaxed precontracted basilar arteries, with higher potency in diabetic than in control rabbits. In arteries from both groups of animals, endothelium removal reduced ANP-induced relaxations. Inhibition of NO-synthesis attenuated ANP-induced relaxation but this attenuation was lower in diabetic than in control ra…

Loop diuretics decrease the renal elimination rate and increase the plasma levels of trimethylamine‐N‐oxide

2018

Aims Trimethylamine-N-oxide (TMAO) is a novel cardiovascular risk marker. We explored the association of commonly used cardiovascular medications with TMAO levels in patients and validated the identified associations in mice. Methods Detailed history of drug treatment was recorded in 300 patients with cardiovascular disease without diabetes in an observational, cross-sectional study. Animal study was performed in CD1 mice. Results Median plasma TMAO (interquartile range) level was 2.144 (1.570-3.104) μmol l-1 . Among nine cardiovascular drug groups, the use of loop diuretics (0.510 ± 0.296 in users vs. 0.336 ± 0.272 in nonusers, P = 0.008) and mineralocorticoid receptor antagonists (0.482 ±…

Kinetic evidence for interaction of TMPyP4 with two different G-quadruplex conformations of human telomeric DNA

2018

Background: Stabilization of G-quadruplex helices by small ligands has attracted growing attention because they inhibit the activity of the enzyme telomerase, which is overexpressed in> 80% cancer cells. TMPyP4, one of the most studied G-quadruplex ligands, is used as a model to show that the ligands can exhibit different binding features with different conformations of a human telomeric specific sequence. Methods: UV–Vis, FRET melting Assay, Isothermal Titration Calorimetry, Time-resolved Fluorescence lifetime, T-Jump and Molecular Dynamics. Results: TMPyP4 yields two different complexes with two Tel22 telomeric conformations in the presence of Na+ or K+. T-Jump kinetic experiments show th…

2016

AbstractCholinergic regulation of arterial luminal diameter involves intricate network of intercellular communication between the endothelial and smooth muscle cells that is highly dependent on the molecular mediators released by the endothelium. Albeit the well-recognized contribution of nitric oxide (NO) towards vasodilation, the identity of compensatory mechanisms that maintain vasomotor tone when NO synthesis is deranged remain largely unknown in the ophthalmic artery. This is the first study to identify the vasodilatory signalling mechanisms of the ophthalmic artery employing wild type mice. Acetylcholine (ACh)-induced vasodilation was only partially attenuated when NO synthesis was in…