Search results for "nitrates"
showing 10 items of 119 documents
Ammonium acts systemically while nitrate exerts an additional local effect on Medicago truncatula nodules
2020
National audience; Symbiotic nitrogen fixation (SNF) has a high energetic cost for legume plants; legumes thus reduce SNF when soil N is available. The present study aimed to increase our understanding regarding the impacts of the two principal forms of available N in soils (ammonium and nitrate) on SNF. We continuously measured the SNF of Medicago truncatula under controlled conditions. This permitted nodule sampling for comparative transcriptome profiling at points connected to the nodules' reaction following ammonium or nitrate applications. The N component of both ions systemically induced a rhythmic pattern of SNF, while the activity in control plants remained constant. This rhythmic a…
Environmental factors influencing the spatio-temporal distribution of Carybdea marsupialis (Lineo, 1978, Cubozoa) in South-Western Mediterranean coas…
2017
21 pages, 5 figures, 2 tables, supporting information 10.1371/journal.pone.0181611.s001, 10.1371/journal.pone.0181611.s002, 10.1371/journal.pone.0181611.s003, 10.1371/journal.pone.0181611.s004, 10.1371/journal.pone.0181611.s005, 10.1371/journal.pone.0181611.s006
A meta-analysis on the ecological effects of aquaculture on the water column: dissolved nutrients
2007
Environmental effects of aquaculture loadings have often been reviewed descriptively, and thus have not provided quantitative estimates of the overall response in the water column. Meta-analytical reviewing techniques allow the contextualisation of quantitative effects in the domain of current literature. In the present paper, more than 50 peer-reviewed articles were analysed and about 425 study cases used to test whether worldwide cultivations have a differential effect on dissolved nutrient levels. Meta-analysis feasibility depends on obtaining an estimate of the effect size from every study and the most common measure of effect size (Hedges’ d) is the difference between means of controls…
Characterization of NO-Induced Nitrosative Status in Human Placenta from Pregnant Women with Gestational Diabetes Mellitus
2017
Dysregulation of NO production is implicated in pregnancy-related diseases, including gestational diabetes mellitus (GDM). The role of NO and its placental targets in GDM pregnancies has yet to be determined. S-Nitrosylation is the NO-derived posttranslational protein modification that can modulate biological functions by forming NO-derived complexes with longer half-life, termed S-nitrosothiol (SNO). Our aim was to examine the presence of endogenous S-nitrosylated proteins in cysteine residues in relation to antioxidant defense, apoptosis, and cellular signal transduction in placental tissue from control (n=8) and GDM (n=8) pregnancies. S-Nitrosylation was measured using the biotin-switch …
Vascular biotransformation of organic nitrates is independent of cytochrome P450 monooxygenases
2020
Background and Purpose Organic nitrates such as nitroglycerin (NTG) or pentaerythritol tetranitrate (PETN) have been used for over a century in the treatment of angina or ischaemic heart disease. These compounds are prodrugs which release their nitrovasodilators upon enzymic bioactivation by aldehyde dehydrogenase (ALDH2) or cytochromes P450 (CYP). Whereas ALDH2 is known to directly activate organic nitrates in vessels, the contribution of vascular CYPs is unknown and was studied here. Experimental Approach As all CYPs depend on cytochrome P450 reductase (POR) as electron donor, we generated a smooth muscle cell-specific, inducible knockout mouse of POR (smcPOR−/−) to investigate the contri…
Protein-bound tyrosine oxidation, nitration and chlorination by-products assessed by ultraperformance liquid chromatography coupled to tandem mass sp…
2015
Abstract Background Free radicals cause alterations in cellular protein structure and function. Oxidized, nitrated, and chlorinated modifications of aromatic amino acids including phenylalanine and tyrosine are reliable biomarkers of oxidative stress and inflammation in clinical conditions. Objective To develop, validate and apply a rapid method for the quantification of known hallmarks of tyrosine oxidation, nitration and chlorination in plasma and tissue proteins providing a snapshot of the oxidative stress and inflammatory status of the organism and of target organs respectively. Material and Methods The extraction and clean up procedure entailed protein precipitation, followed by protei…
Oral health and systemic inflammatory, cardiac and nitroxid biomarkers in hemodialysis patients.
2016
Background Periodontal diseases have systemic inflammatory effects and have been adversely associated with cardiovascular diseases, which are also the most frequent cause of death in the end-stage renal disease. The aim of this cross-sectional study was to investigate the oral health and serum biomarkers among the hemodialysis (HD) patients in Slovenia. Material and Methods 111 HD patients were periodontally examined and their sera were assayed for C reactive protein (CRP), cardiac troponin T (TnT), nitrite/nitrate (NOx) and antibody levels to A. actinomycetemcomitans and P. gingivalis. The association of oral health with systemic response was analyzed with Kruskal-Wallis test, Fisher’s exa…
In vivo effect of N-ethylmaleimide (NEM) on the measurement of nitrate in plasma
2016
Bioavailability of nitric oxide in the body may be estimated by measuring the concentration of nitrate in plasma. However, it has not been reported whether sequestering of aminothiols in plasma affects the concentration of nitrate in the samples.N-ethylmaleimide (NEM) sequesters aminothiols in plasma therefore we tested the in vivo effect of NEM on the concentration nitrate in plasma.Blood samples were collected from 56 healthy subjects in EDTA vials, EDTA vials containing PBS (pH7.4) and EDTA vials containing NEM dissolved in PBS. Nonparametric statistical tests were used to study the effect of NEM on the concentration of nitrate in plasma measured by the Griess reagent assay and by an HPL…
Inorganic nitrite and nitrate in cardiovascular therapy: A better alternative to organic nitrates as nitric oxide donors?
2017
In 1867 the organic nitrite, amyl nitrite, was introduced as a therapeutic agent in the treatment of angina pectoris and was later substituted by the organic nitrate nitroglycerin (NTG). Despite having a highly potent vasodilator capacity in veins>coronary arteries>arterioles, the vasodilator effects NTG are rapidly attenuated by the development of nitrate tolerance. We and others established that NTG treatment stimulates the production of reactive oxygen species such as superoxide and peroxynitrite with subsequent marked attenuation of the NTG vasodilator potency. The nitrite anion (NO2-) has more recently been characterized to possess novel pharmacotherapeutic actions such as modulation o…
Methylophaga and Hyphomicrobium can be used as target genera in monitoring saline water methanol-utilizing denitrification.
2016
Abstract Which bacterial taxonomic groups can be used in monitoring saline water methanol-utilizing denitrification and whether nitrate is transformed into N2 in the process are unclear. Therefore, methylotrophic bacterial communities of two efficiently functioning (nitrate/nitrite reduction was 63–96 %) tropical and cool seawater reactors at a public aquarium were investigated with clone library analysis and 454 pyrosequencing of the 16S rRNA genes. Transformation of nitrate into N2 was confirmed using 15N labeling in incubation of carrier material from the tropical reactor. Combining the data with previous study results, Methylophaga and Hyphomicrobium were determined to be suitable targe…