Search results for "NAD"

Therapeutic effect of enhancing endothelial nitric oxide synthase (eNOS) expression and preventing eNOS uncoupling

2011

Nitric oxide (NO) produced by the endothelium is an important protective molecule in the vasculature. It is generated by the enzyme endothelial NO synthase (eNOS). Similar to all NOS isoforms, functional eNOS transfers electrons from nicotinamide adenine dinucleotide phosphate (NADPH), via the flavins flavin adenine dinucleotide and flavin mononucleotide in the carboxy-terminal reductase domain, to the heme in the amino-terminal oxygenase domain. Here, the substrate L-arginine is oxidized to L-citrulline and NO. Cardiovascular risk factors such as diabetes mellitus, hypertension, hypercholesterolaemia or cigarette smoking reduce bioactive NO. These risk factors lead to an enhanced productio…

Meropenem Permeation through the Outer Membrane of <i>Pseudomonas aeruginosa</i> Can Involve Pathways Other than the OprD Porin Channel

1996

The outer membrane protein (OMP) OprD is the major channel through which carbapenems permeate the outer membrane of Pseudomonas aeruginosa. In this study, we analyzed the OMP profiles of several P. aeruginosa clinical isolates showing diminished susceptibility to imipenem while remaining susceptible to meropenem. All these isolates lacked OprD or showed a reduced expression of this porin. Susceptibility to meropenem was thus independent of the level of OprD expression, indicating that the antimicrobial could be taken up via an alternative route. The level of expression of OprC (70 kD) was also unrelated to meropenem susceptibility. Nevertheless, OMPs OprF and OprE were expressed by all isol…

Biopharma business models in Canada.

2011

This article provides new insights into the different strategy paths or business models currently being implemented by Canadian biopharma companies. Through a case-study methodology, seven biopharma companies pertaining to three business models were analyzed, leading to a broad set of results emerging from the following areas: activity, business model and strategy; management and human resources; and RD, technology and innovation strategy. The three business models represented were: model 1 (conventional biotech oriented to new drug development, radical innovation and search for discoveries); model 2 (development of a technology platform, usually in proteomics and bioinformatics); and model…

Characterizing the interaction between enantiomers of eight psychoactive drugs and highly sulfated-β-cyclodextrin by counter-current capillary electr…

2013

The estimation of apparent binding constants and limit mobilities of the complexes of the enantiomers that characterize the interaction of enantiomers with chiral selectors, in this case highly sulfated β-cyclodextrin, was approached using a simple and economic electrophoretic modality, the complete filling technique (CFT) in counter-current mode. The enantiomers of eight psychoactive drugs, four antihistamines (dimethindene, promethazine, orphenadrine and terfenadine) and four antidepressants (bupropion, fluoxetine, nomifensine and viloxazine) were separated for the first time for this cyclodextrin (CD). Estimations of thermodynamic and electrophoretic enantioselectivies were also performe…

Molecular Mechanisms of the Crosstalk Between Mitochondrial and NADPH Oxidase Derived Reactive Oxygen Species in White Blood Cells - Implications for…

2012

The spasmogenic effects of vanadate in human isolated bronchus

1997

1. Inhalation of vanadium compounds, particularly vanadate, is a cause of occupational bronchial asthma. We have now studied the action of vanadate on human isolated bronchus. Vanadate (0.1 microM-3 mM) produced concentration-dependent, well-sustained contraction. Its -logEC50 was 3.74 +/- 0.05 (mean +/- s.e.mean) and its maximal effect was equivalent to 97.5 +/- 4.2% of the response to acetylcholine (ACh, 1 mM). 2. Vanadate (200 microM)-induced contraction of human bronchus was epithelium-independent and was not inhibited by indomethacin (2.8 microM), zileuton (10 microM), a mixture of atropine, mepyramine and phentolamine (each at 1 microM), or by mast cell degranulation with compound 48/…

Search for New Antihistaminic Compounds by Molecular Connectivity

1999

In this paper it is demonstrated that by adequate selection of topological descriptors we can make possible the prediction of different pharmacological properties, such as plasmatic concentration or sedative effect, within a group of antihistaminic drugs. Moreover, also demonstrated is the usefulness of molecular connectivity in the search of new active compounds. Examples of such compounds are 4-(l-buthylpenthyl)pyridine, N-(3-bromopropyl)-phtalimide and N-(3-chlorpropyl)-piperidin hydrochloride. All of them show antihistaminic activity values more than 30% higher than that of terfenadine, which is used as the reference drug.

Tunable Optical Antennas Using Vanadium Dioxide Metal-Insulator Phase Transitions

2019

Here, we investigate the possibility of exploiting the insulator-to-metal transition in vanadium dioxide (VO2) to tune and optically control the resonances of dipole nanoantennas in the visible near-infrared region. We compare the results obtained in the case of antennas completely made by VO2 with those of previous works and highlight the key role of the substrate to perform dynamical tuning. We also present a highly efficient configuration composed of dipole gold antenna loaded with VO2 and give some general guidelines to optimally exploit phase transitions to tune nanodevices.

Lattice dynamics ofYVO4at high pressures

2010

We report an experimental and theoretical lattice-dynamics study of yttrium orthovanadate $({\text{YVO}}_{4})$ up to 33 GPa together with a theoretical study of its structural stability under pressure. Raman-active modes of the zircon phase are observed up to 7.5 GPa, where the onset of an irreversible zircon-to-scheelite phase transition is detected, and Raman-active modes in the scheelite structure are observed up to 20 GPa, where a reversible second-order phase transition occurs. Our ab initio total-energy calculations support that the second-order phase transition in ${\text{YVO}}_{4}$ is from the scheelite to the monoclinic M-fergusonite structure. The M-fergusonite structure remains u…

First-Principles Study on Polymorphs of AgVO3: Assessing to Structural Stabilities and Pressure-Induced Transitions

2017

In this paper, we present a comprehensive theoretical study, based on density-functional theory calculations, and which focuses on the structural and electronic properties of silver vanadium oxide (AgVO3) in the monoclinic [Cm (β-AgVO3), C2/c (α-AgVO3), and Cc], orthorhombic (Amm2), and cubic (Pm3̅m) phases from 0–30 GPa. The structural and electronic properties, the stability of different phases, and the pressure-induced solid–solid phase transitions of AgVO3 have been previously studied. The effects of pressure on the band structures, energy–gap values, density of states, and vibrational frequencies are also studied. Numerical and analytical calculations are conducted to obtain the lattic…