Monooxygenase system and nitrogen oxide exchange in liver microsomes of rats with toxic hepatitis and the impact of sesquiterpene lactones

2021 ◽  
Vol 172 (8) ◽  
pp. 157-161
Author(s):  
N. V. Tursunova ◽  
◽  
V. N. Syrov ◽  
Z. A. Khushbaktova ◽  
Yu. V. Tornuev ◽  
...  
Keyword(s):  
Nitrogen Oxide ◽  
Toxic Hepatitis ◽  
Sesquiterpene Lactones ◽  
Liver Microsomes ◽  
Monooxygenase System ◽  
The Impact

Monooxygenase System and NO Metabolism in Liver Microsomes of Rats with Toxic Hepatitis and the Effect of Sesquiterpene Lactones

2021 ◽  
Vol 172 (2) ◽  
pp. 133-136
Author(s):  
N. V. Tursunova ◽  
V. N. Syrov ◽  
Z. A. Khushbaktova ◽  
Yu. V. Tornuev ◽  
M. G. Klinnikova
Keyword(s):  
Toxic Hepatitis ◽  
Sesquiterpene Lactones ◽  
Liver Microsomes ◽  
Monooxygenase System

scholarly journals Model-Based Control of Torque and Nitrogen Oxide Emissions in a Euro VI 3.0 L Diesel Engine through Rapid Prototyping

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1107
Author(s):  
Stefano d’Ambrosio ◽  
Roberto Finesso ◽  
Gilles Hardy ◽  
Andrea Manelli ◽  
Alessandro Mancarella ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Rapid Prototyping ◽  
Nitrogen Oxide ◽  
Thermal State ◽  
Pollutant Emissions ◽  
Computational Time ◽  
Nox Emissions ◽  
Model Based ◽  
Brake Mean Effective Pressure ◽  
The Impact

In the present paper, a model-based controller of engine torque and engine-out Nitrogen oxide (NOx) emissions, which was previously developed and tested by means of offline simulations, has been validated on a FPT F1C 3.0 L diesel engine by means of rapid prototyping. With reference to the previous version, a new NOx model has been implemented to improve robustness in terms of NOx prediction. The experimental tests have confirmed the basic functionality of the controller in transient conditions, over different load ramps at fixed engine speeds, over which the average RMSE (Root Mean Square Error) values for the control of NOx emissions were of the order of 55–90 ppm, while the average RMSE values for the control of brake mean effective pressure (BMEP) were of the order of 0.25–0.39 bar. However, the test results also highlighted the need for further improvements, especially concerning the effect of the engine thermal state on the NOx emissions in transient operation. Moreover, several aspects, such as the check of the computational time, the impact of the controller on other pollutant emissions, or on the long-term engine operations, will have to be evaluated in future studies in view of the controller implementation on the engine control unit.

scholarly journals Effect of P450 Oxidoreductase Polymorphisms on the Metabolic Activities of Ten Cytochrome P450s Varied by Polymorphic CYP Genotypes in Human Liver Microsomes

2018 ◽  
Vol 47 (4) ◽  
pp. 1604-1616 ◽  
Author(s):  
Yan Fang ◽  
Na Gao ◽  
Xin Tian ◽  
Jun Zhou ◽  
Hai-Feng Zhang ◽  
...  
Keyword(s):  
Gene Polymorphisms ◽  
High Performance ◽  
Liver Microsomes ◽  
Nucleotide Polymorphisms ◽  
Liquid Chromatograph ◽  
Single Nucleotide ◽  
P450 Oxidoreductase ◽  
Human Livers ◽  
Metabolic Activities ◽  
The Impact

Background/ Aims: Little is known about the effect of P450 oxidoreductase (POR) gene polymorphisms on the activities of CYPs with multiple genotypes. Methods: We genotyped 102 human livers for 18 known POR single nucleotide polymorphisms (SNPs) with allelic frequencies greater than 1% as well as for 27 known SNPs in 10 CYPs. CYP enzyme activities in microsomes prepared from these livers were determined by measuring probe substrate metabolism by high performance liquid chromatograph. Results: We found that the effects of the 18 POR SNPs on 10 CYP activities were CYP genotype-dependent. The POR mutations were significantly associated with decreased overall Km for CYP2B6 and 2E1, and specific genotypes within CYP1A2, 2A6, 2B6, 2C8, 2D6 and 2E1 were identified as being affected by these POR SNPs. Notably, the effect of a specific POR mutation on the activity of a CYP genotype could not be predicted from other CYP genotypes of even the same CYP. When combining one POR SNP with other POR SNPs, a hitherto unrecognized effect of multiple-site POR gene polymorphisms (MSGP) on CYP activity was uncovered, which was not necessarily consistent with the effect of either single POR SNP. Conclusions: The effects of POR SNPs on CYP activities were not only CYP-dependent, but more importantly, CYP genotype-dependent. Moreover, the effect of a POR SNP alone and in combination with other POR SNPs (MSGP) was not always consistent, nor predictable. Understanding the impact of POR gene polymorphisms on drug metabolism necessitates knowing the complete SNP complement of POR and the genotype of the relevant CYPs.

Effect of SNCR on the Properties of Fly Ash in Terms of its Applicability to Concrete

2018 ◽  
Vol 272 ◽  
pp. 107-114 ◽  
Author(s):  
Rudolf Hela ◽  
Martin Ťažký
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Fly Ash ◽  
Nitrogen Oxide ◽  
Catalytic Reduction ◽  
Salt Content ◽  
Reduction Process ◽  
Efficiency Index ◽  
Negative Impacts ◽  
The Impact

At the beginning of 2016, the legislation for regulating and reducing the emission of exhaust gases with regard to reducing nitrogen oxides came into force. The articles published to date point to the possibility of increased ammonium salt content in fly ash that has undergone a selective non-catalytic reduction process. This paper addresses other possible negative impacts of the reduction process for nitrogen oxide on the physico-mechanical properties of high-temperature fly ash, especially the morphology of its grains and its impact on the rheology of the composite and the impact on the efficiency index.

scholarly journals Evaluation of Fluorescence- and Mass Spectrometry—Based CYP Inhibition Assays for Use in Drug Discovery

2008 ◽  
Vol 13 (5) ◽  
pp. 343-353 ◽  
Author(s):  
Leslie Bell ◽  
Shari Bickford ◽  
Phong Hung Nguyen ◽  
Jianling Wang ◽  
Timothy He ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Gold Standard ◽  
Low Cost ◽  
Liver Microsomes ◽  
Standard Approach ◽  
New Chemical Entities ◽  
Cyp Inhibition ◽  
Inhibitory Potential ◽  
The Impact

The potential for metabolism-related drug-drug interactions by new chemical entities is assessed by monitoring the impact of these compounds on cytochrome P450 (CYP) activity using well-characterized CYP substrates. The conventional gold standard approach for in vitro evaluation of CYP inhibitory potential uses pooled human liver microsomes (HLM) in conjunction with prototypical drug substrates, often quantified by LC-MS/MS. However, fluorescent CYP inhibition assays, which use recombinantly expressed CYPs and fluorogenic probe substrates, have been employed in early drug discovery to provide low-cost, high-throughput assessment of new chemical entities. Despite its greatly enhanced throughput, this approach has been met with mixed success in predicting the data obtained with the conventional gold standard approach (HLM+LC-MS). The authors find that the predictivity of fluorogenic assays for the major CYP isoforms 3A4 and 2D6 may depend on the quality of the test compounds. Although the structurally more optimized marketed drugs yielded acceptable correlations between the fluorogenic and HLM+LC-MS/MS assays for CYPs 3A4, 2D6, and 2C9 ( r 2 = 0.5-0.7; p < 0.005), preoptimization, early discovery compounds yielded poorer correlations ( r 2 ≤ 0.2) for 2 of these major isoforms, CYPs 3A4 and 2D6. Potential reasons for the observed differences are discussed. ( Journal of Biomolecular Screening 2008;343-353)

scholarly journals Biogenic nitrogen oxide emissions from soils – impact on NO<sub>x</sub> and ozone over West Africa during AMMA (African Monsoon Multidisciplinary Experiment): modelling study

2008 ◽  
Vol 8 (9) ◽  
pp. 2351-2363 ◽  
Author(s):  
C. Delon ◽  
C. E. Reeves ◽  
D. J. Stewart ◽  
D. Serça ◽  
R. Dupont ◽  
...  
Keyword(s):  
Neural Network ◽  
Soil Moisture ◽  
Nitrogen Oxide ◽  
Lower Troposphere ◽  
Environmental Parameters ◽  
Biogenic Emissions ◽  
Convective System ◽  
Sahel Region ◽  
The Impact ◽  
No Emissions

Abstract. Nitrogen oxide biogenic emissions from soils are driven by soil and environmental parameters. The relationship between these parameters and NO fluxes is highly non linear. A new algorithm, based on a neural network calculation, is used to reproduce the NO biogenic emissions linked to precipitations in the Sahel on the 6 August 2006 during the AMMA campaign. This algorithm has been coupled in the surface scheme of a coupled chemistry dynamics model (MesoNH Chemistry) to estimate the impact of the NO emissions on NOx and O3 formation in the lower troposphere for this particular episode. Four different simulations on the same domain and at the same period are compared: one with anthropogenic emissions only, one with soil NO emissions from a static inventory, at low time and space resolution, one with NO emissions from neural network, and one with NO from neural network plus lightning NOx. The influence of NOx from lightning is limited to the upper troposphere. The NO emission from soils calculated with neural network responds to changes in soil moisture giving enhanced emissions over the wetted soil, as observed by aircraft measurements after the passing of a convective system. The subsequent enhancement of NOx and ozone is limited to the lowest layers of the atmosphere in modelling, whereas measurements show higher concentrations above 1000 m. The neural network algorithm, applied in the Sahel region for one particular day of the wet season, allows an immediate response of fluxes to environmental parameters, unlike static emission inventories. Stewart et al (2008) is a companion paper to this one which looks at NOx and ozone concentrations in the boundary layer as measured on a research aircraft, examines how they vary with respect to the soil moisture, as indicated by surface temperature anomalies, and deduces NOx fluxes. In this current paper the model-derived results are compared to the observations and calculated fluxes presented by Stewart et al (2008).

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