scholarly journals Liquid Chromatographic Investigation of Spontaneous Oscillatory In Vitro Chiral Conversion and Spontaneous Oscillatory Condensation of Simple Carboxylic Acids in Aqueous and Nonaqueous Media

2011 ◽  
Vol 2011 ◽  
pp. 1-11
Author(s):  
Mieczyslaw Sajewicz ◽  
Teresa Kowalska
Keyword(s):  
Carboxylic Acids ◽  
Small Contribution ◽  
Nonaqueous Media ◽  
Analytical Technique ◽  
Oxidation Reduction ◽  
Oscillatory Reactions ◽  
Liquid Chromatographic ◽  
Chromatographic Evidence ◽  
Organic Oxidation

Oscillatory reactions are a narrow reaction type among the entity of chemical reactions and those involving purely organic compounds make a small contribution to an overall number of all known oscillatory reactions. The most abundant type is purely inorganic and mixed inorganic-organic oxidation-reduction reactions, basically because monitoring them is relatively easy (e.g., with use of potentiometric measurements). Investigation of the organic reactions can be more demanding, and then chromatography is an analytical technique of choice. In this paper, we provide an overview of chromatographic evidence with oscillatory reactions discovered in our laboratory in the course of the last several years that involve the low-molecular-weight carboxylic acids (profen drugs, amino acids, and hydroxy acids). The investigated processes comprise the oscillatory chiral conversion and the oscillatory condensation, spontaneously running in the aqueous and nonaqueous abiotic media, and they were traced with use of TLC and HPLC coupled with different detector types.

The Effect of Pentosan Polysulphate (SP54) on the Fibrinolytic Enzyme System - A Human Volunteer and Experimental Animal Study

1985 ◽  
Vol 54 (04) ◽  
pp. 833-837 ◽  
Author(s):  
N A Marsh ◽  
P M Peyser ◽  
L J Creighton ◽  
M Mahmoud ◽  
P J Gaffney
Keyword(s):  
Plasminogen Activator ◽  
Surface Effect ◽  
Ex Vivo ◽  
Vena Cava ◽  
Tissue Type ◽  
Similar Response ◽  
Small Contribution ◽  
Thrombosis Model ◽  
Pentosan Polysulphate

SummaryPentosan polysulphate causes an increase in plasminogen activator activity in plasma both after oral ingestion and after subcutaneous injection. The effect is greatest after 3 h and has disappeared by 6 h. Repeat doses by mouth over 5 days elicit a similar response. The recorded increase in activity is due largely to the release of tissue-type plasminogen activator (tPA) from the endothelium according to the antigen assay although there could be a small contribution from Factor XH-related “intrinsic” fibrinolysis induced in vitro. SP54 enhances activity ex vivo by a non-specific surface effect, and this phenomenon may contribute the increased levels of activity seen in vitro. Administration of SP54 to animals elicits a similar increase in activator activity, the intramuscular route being slightly more effective. Results with an inferior vena cava thrombosis model in the rat suggest that pentosan polysulphate may induce a thrombolytic effect.

New Fe–Cu bimetallic coordination compounds based on ω-ferrocene carboxylic acids and 2-thioimidazol-4-ones: structural, mechanistic and biological studies

2021 ◽  
Author(s):  
Dmitry A. Guk ◽  
Olga O. Krasnovskaya ◽  
Anna A. Moiseeva ◽  
Victor A. Tafeenko ◽  
Nikolay V. Ul'yanovskii ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Coordination Compounds ◽  
Copper Complexes ◽  
Biological Studies

Synthesis, characterization and in vitro cytotoxic investigation of a series of new ferrocene-containing derivatives based on ω-ferrocene carboxylic acids and 2-alkylthioimidazolin-4-ones and their copper complexes have been reported.

scholarly journals Inhibition of prolyl oligopeptidase by flavonoids isolated from the roots of Allexis obanensis (Baker f.) Melch

2021 ◽  
Vol 1 (2) ◽  
pp. 39-44
Author(s):  
Olivier Ndogo Eteme ◽  
Nkwengoua Tchouboun Zondegoumba Ernestine ◽  
Soh Desire ◽  
Oladimeji Taiwo Babatunde ◽  
Barthelemy Nyasse
Keyword(s):  
Neurodegenerative Diseases ◽  
Column Chromatography ◽  
Inhibitory Activity ◽  
High Performance ◽  
High Performance Liquid Chromatographic ◽  
Chromatographic Technique ◽  
Carboxy Terminus ◽  
Prolyl Oligopeptidase ◽  
Liquid Chromatographic

Background: Prolyl oligopeptidase is a cytosolic serine peptidase that hydrolyzes peptides containing proline at the carboxy terminus of proline residues. It has been associated with several neurodegenerative diseases. Therefore, it is a target in the management of these disease conditions. Methods: Allexis obanensis was taken through cold extraction, subjected to column chromatography and flavonoids isolated via high-performance liquid chromatographic technique. The flavonoids obtained were investigated for their in vitro prolyl oligopeptidase inhibitory activity. Results: The flavonoids isolated include: 4.4'''- dimethoxylophirone A [1] and 7-hydroxy-3-(3-hydroxy-4 méthoxyphenyl)-5- méthoxy-4H chromen-4-one [2]. They inhibited prolyl oligopeptidase at low IC50 concentrations of 7.201±3.021 µM and 6.223±2.002 µM respectively. Conclusion: The results obtained from this study proves the potential of these flavonoids as prolyl oligopeptidase inhibitors, by inference, their potentiality in the management of neuropsychiatric disorders.

scholarly journals In vitro skin penetration of clobetasol from lipid nanoparticles: drug extraction and quantitation in different skin layers

2012 ◽  
Vol 48 (4) ◽  
pp. 811-817 ◽  
Author(s):  
Luís Antônio Dantas Silva ◽  
Stephânia Fleury Taveira ◽  
Eliana Martins Lima ◽  
Ricardo Neves Marreto
Keyword(s):  
Stratum Corneum ◽  
Topical Therapy ◽  
Entrapment Efficiency ◽  
Skin Penetration ◽  
Drug Accumulation ◽  
Uniform Size ◽  
Liquid Chromatographic Method ◽  
Systemic Side Effects ◽  
Liquid Chromatographic

Clobetasol propionate (CP) is a potent topical corticosteroid that causes several cutaneous and systemic side effects. In the present work, CP was encapsulated in nanostructured lipid carriers (NLCs) to increase drug retention in the outer skin layers and improve the safety of topical therapy. NLCs were prepared using a microemulsion technique with a mixture of lecithin, taurodeoxycholate, stearic acid, and oleic acid. In vitro penetration studies were performed in a modified Franz-type diffusion cell, and porcine ears were used as a model of human skin. A simple and sensitive liquid chromatographic method was developed and validated for clobetasol determination in different skin layers. NLCs presented uniform size distribution, high zeta potentialand entrapment efficiency values (> 98%). The analytical procedure was validated according to FDA guidelines. Clobetasol recoveries from skin samples were higher than 85%, with no interference of skin components and NLC ingredients. In experiments, after 6 h, a higher drug accumulation in the stratum corneum arising from NLCs compared to aqueous CP solution was observed. Thus, the NLCs demonstrated high potential for targeting CP to the skin and ensuring drug accumulation in the stratum corneum.

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