Alcohol‐activated vanadium‐containing polyoxometalate complexes in homogeneous glucose oxidation identified with 51V‐NMR and EPR spectroscopy

The first step of electrochemical oxidation of 2-phenyl- and 2-(4-tolyl)-1,3,4,7-tetramethylisoindoles in anhydrous acetonitrile produces relatively stable cationradicals which have been studied by means of EPR spectroscopy using the method of internal electrochemical generation of radicals under reduced temperature. The same electrochemical behaviour of the both studied derivatives and identical EPR spectra of their cationradicals can be explained within the Huckel MO method. The largest contribution to the magnitude of splitting constant of nitrogen nucleus is due to π-σ-spin polarization of C-N bonds caused by high spin abundance of pz-AO of carbon atoms. Half-life of decomposition of the studied cationradicals is 4 min at -30°C.

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Photoassisted Production of O2-• and H2 in Aqueous Medium Stimulated by Polythiophene in ZSM-5 Zeolite Channels

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19990149 ◽

1999 ◽

Vol 64 (1) ◽

pp. 149-156 ◽

Cited By ~ 7

Author(s):

Gabriel Čík ◽

František Šeršeň ◽

Alena Bumbálová

Keyword(s):

Reactive Oxygen Species ◽

Ion Exchange ◽

Visible Light ◽

Aqueous Medium ◽

Exchange Reaction ◽

Epr Spectroscopy ◽

Reactive Oxygen ◽

Oxygen Species ◽

Water Reduction ◽

Ion Exchange Reaction

The formation of reactive oxygen species due to irradiation by a visible light of the polythiophene deposited in ZSM-5 zeolite channels in aqueous medium has been studied. Polymerization of thiophene was carried out in zeolite channels after the ion-exchange reaction of Na+ for Fe3+. By means of EPR spectroscopy, the temporarily generated 1O2 in irradiated aqueous medium was proved. The formation of O2-• was confirmed by the reduction of Fe3+-cytochrome c. Irradiation led to the water reduction to hydrogen.

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Effects of peroral alanine administration in lactating ewes with decreased availability of glucose

British Journal Of Nutrition ◽

10.1079/bjn19970196 ◽

1997 ◽

Vol 78 (5) ◽

pp. 805-813 ◽

Cited By ~ 1

Author(s):

Kjell Holtenius ◽

Paul Holtenius

Keyword(s):

Fatty Acids ◽

Plasma Level ◽

Free Fatty Acids ◽

Skeletal Muscles ◽

Plasma Insulin ◽

Glucose Oxidation ◽

Negative Energy ◽

Crossover Design ◽

Metabolic Effects ◽

Significant Elevation

The metabolic effects of a phlorizin-induced drainage of glucose were studied in six lactating ewes with or without peroral alanine drenches in a study of crossover design. Phlorizin gave rise to a small, but significant, elevation of plasma β-hydroxybutyrate. The plasma level of alanine decreased by about 30 % due to the phlorizin injections and alanine was negatively correlated to β-hydroxybutyrate. The plasma level of free fatty acids increased due to phlorizin. Plasma insulin and glucose concentrations were not significantly affected by phlorizin while glucagon level showed a small but significant increase. Peroral alanine drenches to phlorizin-treated ewes gave rise to a transitory elevation of alanine in plasma. The plasma level of free fatty acids was about 40 % lower in phlorizin-treated ewes receiving alanine and β-hydroxybutyrate tended to be lower (P < 0.08). We suggest that β-hydroxybutyrate, apart from its function as an oxidative fuel, might play an important role by limiting glucose oxidation and protein degradation in skeletal muscles during periods of negative energy balance in ruminants. Furthermore, it is suggested that alanine supplementation decreases lipolysis and ketogenesis in lactating ewes.

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Formation of different types of paramagnetic centers in the alanine dosimeters exposed to alpha and gamma radiation - Study by EPR spectroscopy

Radiation Measurements ◽

10.1016/j.radmeas.2020.106467 ◽

2020 ◽

pp. 106467

Author(s):

A.I. Ivannikov ◽

A.M. Khailov ◽

S.P. Orlenko ◽

V.F. Stepanenko ◽

F. Trompier ◽

...

Keyword(s):

Gamma Radiation ◽

Epr Spectroscopy ◽

Paramagnetic Centers ◽

Radiation Study ◽

Different Types

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Metabolic and endothelial effects of trimetazidine on forearm skeletal muscle in patients with type 2 diabetes and ischemic cardiomyopathy

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00083.2005 ◽

2006 ◽

Vol 290 (1) ◽

pp. E54-E59 ◽

Cited By ~ 35

Author(s):

Lucilla D. Monti ◽

Emanuela Setola ◽

Gabriele Fragasso ◽

Riccardo P. Camisasca ◽

Pietro Lucotti ◽

...

Keyword(s):

Type 2 Diabetes ◽

Lipid Oxidation ◽

Ischemic Cardiomyopathy ◽

Glucose Oxidation ◽

Diabetic Patients ◽

Vascular Effects ◽

Type 2 Diabetic Patients ◽

Double Blind ◽

Endothelin 1

The aim of the present study was to evaluate the effect of prolonged inhibition of β-oxidation on glucose and lipid muscle forearm metabolism and cGMP and endothelin-1 forearm release in patients with type 2 diabetes mellitus and ischemic cardiomyopathy. Fifteen patients were randomly allocated in a double-blind cross-over parallel study with trimetazidine (20 mg tid) or placebo lasting 15 days. At the end of each period, all patients underwent euglycemic hyperinsulinemic clamps with forearm indirect calorimetry and endothelial balance of vasodilator and vasoconstricor factors. Compared with placebo, trimetazidine induced 1) an increase in insulin-induced forearm glucose uptake and glucose oxidation accompained by a reduction in forearm lipid oxidation and citrate release and 2) a decrease of endothelin-1 release paralleled by a significant increase in forearm cGMP release. Forearm glucose oxidation significantly correlated with cGMP release ( r = 0.37, P < 0.04), whereas forearm lipid oxidation positively correlated with endothelin-1 release ( r = 0.40, P < 0.03). In conclusion, for the first time, we demonstrated that insulin-induced forearm glucose oxidation and forearm cGMP release were increased whereas forearm endothelin-1 release was decreased during trimetazidine treatment. Muscle's metabolic and vascular effects of trimetazidine add new interest in the use of trimetazidine in type 2 diabetic patients with cardiovascular disease.

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