Search results for "citrate"

Small Gold Nanoparticles Synthesized with Sodium Citrate and Heavy Water: Insights into the Reaction Mechanism

2010

5 páginas, 3 figuras, 1 esquema.

6-Phosphofructokinase from frog skeletal muscle: purification and properties

1990

Comparison of α-acetolactate synthase and α-acetolactate decarboxylase in Lactococcus spp. and Leuconostoc spp.

1994

Cell-free extracts of Leuconostoc and Lactococcus species were tested for their alpha-acetolactate synthase and alpha-acetolactate decarboxylase activities. In Leuconostoc mesenteroides subsp. cremoris, Leuconostoc mesenteroides subsp. mesenteroides and Leuconostoc lactis, the Km of alpha-acetolactate synthase for pyruvate was close to 10 mM whereas it was 30 mM in Lactococcus lactis subsp. lactis biovar. diacetylactis. The Km of alpha-acetolactate decarboxylase for alpha-acetolactic acid was very low (0.3 mM) in Leuconostoc species in comparison to Lactococcus lactis subsp. lactis biovar. diacetylactis (60 mM). In the latter bacterium, alpha-acetolactate decarboxylase showed a sigmoidal de…

A conserved role for the mitochondrial citrate transporter Sea/SLC25A1 in the maintenance of chromosome integrity.

2009

Histone acetylation plays essential roles in cell cycle progression, DNA repair, gene expression and silencing. Although the knowledge regarding the roles of acetylation of histone lysine residues is rapidly growing, very little is known about the biochemical pathways providing the nucleus with metabolites necessary for physiological chromatin acetylation. Here, we show that mutations in the scheggia (sea)-encoded Sea protein, the Drosophila ortholog of the human mitochondrial citrate carrier Solute carrier 25 A1 (SLC25A1), impair citrate transport from mitochondria to the cytosol. Interestingly, inhibition of sea expression results in extensive chromosome breakage in mitotic cells and indu…

Riociguat versus sildenafil on hypoxic pulmonary vasoconstriction and ventilation/perfusion matching

2017

Introduction Current treatment with vasodilators for pulmonary hypertension associated with respiratory diseases is limited by their inhibitory effect on hypoxic pulmonary vasoconstriction (HPV) and uncoupling effects on ventilation-perfusion (V'/Q'). Hypoxia is also a well-known modulator of the nitric oxide (NO) pathway, and may therefore differentially affect the responses to phosphodiesterase 5 (PDE5) inhibitors and soluble guanylyl cyclase (sGC) stimulators. So far, the effects of the sGC stimulator riociguat on HPV have been poorly characterized. Materials and methods Contraction was recorded in pulmonary arteries (PA) in a wire myograph. Anesthetized rats were catheterized to record …

Glucosamine Supplementation Improves Physical Performance in Trained Mice

2021

Introduction D-Glucosamine (GlcN) is one of the most widely consumed dietary supplements and complementary medicines in the world and has been traditionally used to attenuate osteoarthritis in humans. GlcN extends lifespan in different animal models. In humans, its supplementation has been strongly associated with decreased total mortality and improved vascular endothelial function. GlcN acts as a suppressor of inflammation and by inhibiting glycolysis, it can activate the metabolism of stored fat and mitochondrial respiration. Methods The conventional human GlcN dose is 1,500 mg x day-1 but extensive evidence indicates that much higher doses are well tolerated. GlcN is one of the supplemen…

Pulmonary vascular resistance as a potential marker of reactive pulmonary hypertension reduction following sildenafil therapy in patients disqualifie…

2019

Purpose:We sought to determine the predictors of restoration of heart transplantation (HTx) candidacy in pa-tients with systolic heart failure (HF) and reactive fixed pulmonary hypertension (RFPH) defined as pulmonaryvascular resistance (PVR) > 2.5 Wood units (WU), transpulmonary gradient (TPG) > 12 mmHg or ≤2.5 WUwith systolic arterial pressure ≤85 mmHg during vasoreactivity test, following sildenafil therapy.Material and methods:Between2007and20181136patientswereevaluatedatourdepartmentascandidatesforHTx. Thirty-five of them, who presented with systolic HF and were not eligible for HTx due to RFPH, wereincluded in the study (31 men aged 55.1 ± 7.4 years). In all the patients sildenafil wa…

Fluorescent benzofurazan-cholic acid conjugates for in vitro assessment of bile acid uptake and its modulation by drugs.

2009

One of the most common mechanisms of hepatotoxicity is drug-induced cholestasis. Hence, new approaches for screening the cholestatic potential of drug candidates are desirable. In this context, we describe herein the use of synthetic 4-nitrobenzo-2-oxa-1,3-diazole (NBD) fluorescent conjugates of cholic acid (ChA) at positions 3alpha, 3beta, 7alpha, and 7beta for in vitro assessment of bile acid uptake. All the conjugates show a strong absorption band between 400 and 550 nm and have a fluorescence quantum yield of approximately 0.45, with an emission maximum centered at approximately 530 nm. After their photophysical characterization, 3alpha-, 3beta-, 7alpha-, and 7beta-NBD-ChA were used to …

Intergenerational transmission of the positive effects of physical exercise on brain and cognition

2019

Physical exercise has positive effects on cognition, but very little is known about the inheritance of these effects to sedentary offspring and the mechanisms involved. Here, we use a patrilineal design in mice to test the transmission of effects from the same father (before or after training) and from different fathers to compare sedentary- and runner-father progenies. Behavioral, stereological, and whole-genome sequence analyses reveal that paternal cognition improvement is inherited by the offspring, along with increased adult neurogenesis, greater mitochondrial citrate synthase activity, and modulation of the adult hippocampal gene expression profile. These results demonstrate the inher…

Regulatory properties of 6-phosphofructokinase and control of glycolysis in boar spermatozoa.

2007

Glycolysis is crucial for sperm functions (motility and fertilization), but how this pathway is regulated in spermatozoa is not clear. This prompted to study the location and the regulatory properties of 6-phosphofructokinase (PFK, EC 2.7.1.11), the most important element for control of glycolytic flux. Unlike some other glycolytic enzymes, PFK showed no tight binding to sperm structures. It could readily be extracted from ejaculated boar spermatozoa by sonication and was then chromatographically purified. At physiological pH, the enzyme was allosterically inhibited by near-physiological concentrations of its co-substrate ATP, which induced co-operativity, i.e. reduced the affinity for the …