Search results for "ALDEHYDE"
showing 10 items of 915 documents
Manipulation of the DA signal on the onset of relapse of ACD
2013
It's widely known that all addictive drugs show analogous pathological behaviours consisting in compulsive drug seeking,loss of self –control and propensity to relapse. This evidence is suggestive of a common brain mechanism involving the Ventral Tegmental Area and Nucleus Accumbens whereby mesocorticolimbimc dopamine pathway. Dfferent and apparently anthitetic classes of drugs of abuse manage to increase DA release, in the aforementioned areas (Di Chiara, 1988; 1995). Reductions in activity of the mesolimbic dopamine system in the nucleus accumbes occur during drug withdrawal in animal studies (Weiss F et al. 1992; 1996). Experimental evidences have proven D2 receptor involvement in drug s…
209 New Fricke gel with high sensitivity and low diffusion for 3D-MRI dosimetry
2018
Purpose Fricke gel (FG) dosimeters are good candidates for 3D dose assessment in biological materials. Their effective atomic number and density are similar to those of soft tissue. In view of their chemical and morphological characteristics, FG serve as dosimeters and as phantoms at the same time. FG dosimeters are obtained by incorporating an acidic aqueous solution of ferrous ions Fe2+ into a gel matrix. In order to address the limitations of gels based on natural matrices, we have studied FG produced with a matrix of poly-vinyl alcohol (PVA) cross-linked with glutaraldehyde (GTA). Materials and methods The proposed gel contains 10% w/v of PVA and GTA of 1%w/v. A common formulation agaro…
P-77D-PENICILLAMINE, A POTENTIAL ETHANOL ANTI-RELAPSE DRUG, DOES NOT REDUCE THE VOLUNTARY ETHANOL INTAKE IN LONG-TERM EXPERIENCED RATS
2015
Experimental evidence has demonstrated that the reinforcing effects of ethanol crucially depend on the brain formation of acetaldehyde (ACD). Rationally supported by this basis, we previously evaluated a novel strategy to prevent relapse in alcoholism based on chemical ACD inactivation using D-Penicillamine (DP). Under our experimental …
Drug-metabolizing enzymes in the skin of man, rat, and pig.
2007
The mammalian skin has long been considered to be poor in drug metabolism. However, many reports clearly show that most drug metabolizing enzymes also occur in the mammalian skin albeit at relatively low specific activities. This review summarizes the current state of knowledge on drug metabolizing enzymes in the skin of human, rat, and pig, the latter, because it is often taken as a model for human skin on grounds of anatomical similarities. However only little is known about drug metabolizing enzymes in pig skin. Interestingly, some cytochromes P450 (CYP) have been observed in the rat skin which are not expressed in the rat liver, such as CYP 2B12 and CYP2D4. As far as investigated most d…
Pre-Clinical Studies with D-Penicillamine as a Novel Pharmacological Strategy to Treat Alcoholism: Updated Evidences
2017
Ethanol, as other drugs of abuse, is able to activate the ventral tegmental area dopamine (VTA-DA) neurons leading to positively motivational alcohol-seeking behavior and use, and, ultimately to ethanol addiction. In the last decades, the involvement of brain-derived acetaldehyde (ACD) in the ethanol actions in the mesolimbic pathway has been widely demonstrated. Consistent published results have provided a mechanistic support to the use of ACD inactivating agents to block the motivational and reinforcing properties of ethanol. Hence, in the last years, several pre-clinical studies have been performed in order to analyze the effects of the sequestering ACD agents in the prevention of ethano…
Coscinolactams A and B: new nitrogen-containing sesterterpenoids from the marine sponge Coscinoderma mathewsi exerting anti-inflammatory properties
2009
Abstract Investigation of the marine sponge Coscinoderma mathewsi led to the isolation of two novel nitrogen-containing cheilanthane sesterterpenoids, coscinolactams A and B, together with known suvanine. The structures were elucidated by extensive spectroscopic measurements including NOE experiments to deduce the stereochemistry. The natural compounds, as well as a semisynthetic derivative, showed moderate anti-inflammatory activity measured as their capability to inhibit PGE2 and NO production. The suvanine aldehyde derivative 4 inhibited inducible nitric oxide protein expression with an IC50 value of 7.3 μM.
Oxide anodes in electro-organic oxidation. Oxidation of maleic addon tungsten oxide anodes
1982
The electrochemical oxidation of maleic acid on tungsten anodes has been investigated. Glyoxal and carbon dioxide were the main products together with tartaric acid and acetaldehyde. Glyoxal is also obtained as the main product from the oxidation ofd-tartaric acid. Under the same conditions succinic acid is completely oxidized to carbon dioxide and water. The anodic dissolution of tungsten and the oxidation of water to oxygen become predominant in the final stages of the electrolyses.
Humic substances as catalysts in condensation reactions
2001
Humic substances (HS) demonstrate appreciable impact on the rate of the condensation reactions as shown in the example of the reaction between hydrazine and 4-(dimethylamino)-benzaldhyde in an aquatic environment. The catalytic activity of HS has also been demonstrated in Knoevenagel and Claisen-Schmidt reactions for condensation of carbonyl compounds with CH acids. The aquatic fulvic acids are the most active in these reactions. The velocity of the studied reactions also depends on pH, temperature, the concentration and origin of HS used. A possible micellar and acid-base catalysis mechanism in aquatic media has been suggested.
Preparation of fouling resistant and highly perm-selective novel PSf/GO-vanillin nanofiltration membrane for efficient water purification
2022
International audience; To meet the rising global demand for water, it is necessary to develop membranes capable of efficiently purifying contaminated water sources. Herein, we report a series of novel polysulfone (PSf)/GO-vanillin nanofiltration membranes highly permeable, selective, and fouling resistant. The membranes are composed of two-dimensional (2D) graphite oxide (GO) layers embedded with vanillin as porogen and PSf as the base polymer. There is a growing interest in addressing the synergistic effect of GO and vanillin on improving the permeability and antifouling characteristics of membranes. Various spectroscopic and microscopic techniques were used to perform detailed physicoche…
Derivatization of ephedrine with o-phthaldialdehyde for liquid chromatography after treatment with sodium hypochlorite.
2000
The usefulness of the reaction with NaClO followed by derivatization with o-phthaldialdehyde (OPA) and N-acetyl-L-cysteine (NAC) has been investigated for the chromatographic analysis of ephedrine. The influence of parameters affecting the two-stage reaction has been evaluated, including concentration of NaClO, time of reaction, temperature and pH. On the basis of these studies, conditions for the pre-column and (automated) post-column determination of ephedrine are presented. The described conditions have been applied to the measurement of ephedrine in the concentration intervals 0.2-20.0 microg/ml and 2.0-50.0 microg/ml for the pre-column and post-column methods, respectively. The possibi…