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  • Author: Șerban Andrei Gâz-Florea x
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Open access

Şerban Andrei Gâz Florea, Adriana Gâz Florea, Hajnal Kelemen and Daniela-Lucia Muntean

Abstract

As more data are generated from proteome and transcriptome analysis revealing that metalloproteinases represent most of the Viperid and Colubrid venom components authors decided to describe in a short review a classification and some of the multiple activities of snake venom metalloproteinases. SVMPs are classified in three major classes (P-I, P-II and P-III classes) based on the presence of various domain structures and according to their domain organization. Furthermore, P-II and P-III classes were separated in subclasses based on distinctive post-translational modifications. SVMPs are synthesized in a latent form, being activated through a Cys-switch mechanism similar to matrix metalloproteinases. Most of the metalloproteinases of the snake venom are responsible for the hemorrhagic events but also have fibrinogenolytic activity, poses apoptotic activity, activate blood coagulation factor II and X, inhibit platelet aggregation, demonstrating that SVMPs have multiple functions in addition to well-known hemorrhagic function.

Open access

Șerban Andrei Gâz-Florea, Eleonora Mircia and Lavinia Berţa

Abstract

Objective: Development of new electronic devices with applications in computer science as well as new medical devices pushed the researcher to find new technologies. Based on those new techniques we have designed and synthesized compounds with possible application in the field of advanced materials. Material and method: Compounds were analyzed by TLC and NMR. Routine 1H NMR (250 MHz) spectra were recorded at room temperature in deuterated acetone, unless stated otherwise. Thin-layer chromatography (TLC) was carried out on aluminum sheets coated with silicagel 60 F254 Merck TLC plates. Results: Starting from commercial available compounds intermediates were obtained in a good yield. 4,4′-(2,4,8,10-tetraoxaspiro[5.5]undecane-3,9-diyl)diphenol was obtained starting from pentaerythritol and p-hydroxy-benzaldehyde in the presence of catalytic amounts of APTS (p-toluensulfonic acid). The product was purified by recrystallization and characterized by NMR spectroscopy. The structure exhibit 2 different signals for equatorial and axial position. Furthermore di, tri and tetra ethylene glycol were obtained by microwave assisted synthesis in a matter of minutes. Compounds were separated by recrystallization. Conclusions: In conclusion, several intermediates were synthesized and characterized from spectroscopic point of view. Further analyses should be carried out and the compounds should be tested as advanced materials.

Open access

Lavinia Grama, Adrian Man, Daniela-Lucia Muntean, Șerban Andrei Gâz Florea, Francisc Boda and Augustin Curticăpean

Abstract

Polyoxometalates are important inorganic compounds with a broad range of pharmacological properties, including antiviral, antibacterial, antiprotozoal or antitumoral activities, even that their molecular mechanism of action is poorly understood. Purpose: In this paper we evaluated the antibacterial activity of some saturated polyoxotungstates (POW) compounds, since nowadays, the increasing resistance of bacteria to drugs represents a major health problem. Materials and methods: The antibacterial activity was studied by disk diffusion method as a possible screening method and by successive micro-dilutions method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) have been calculated for each compound by successive dilutions. We also compared the reliability of each testing method for this particular POW evaluation. Results: The best antibacterial activity was expressed by H4[SiW12O40]*nH2O and the lowest by Na3[PW12O40]*nH2O, but with very good activity on Staphylococcus spp., especially on MRSA. The POW activity occurs only at relatively high concentrations, and it is dependent on bacterial strain, with very good activity on Staphylococcus spp. The most reliable method for assessing the antibacterial effects of POW is micro-dilutions. POWs could be practically applied in hospital decontamination and could have a possible in vivo antibacterial application.

Open access

Şerban Andrei Gâz Florea, Diana Ciurca, Anca Mare, Adrian Man, Bogdan Cordoş, Anda-Lavinia Grama and Daniela-Lucia Muntean

Abstract

Background: Snake venom is a complex mixture of biologically active substances. Some peptides and proteins from snake have already demonstrated their therapeutically potential. The venom of Naja haje, an Elapidae member, has been analyzed from this point of view. Understanding the fully biochemical role of its enzymes has determined the scientists to find new separation and identification methods.

Objective: Our goal was to develop an optimal HPLC analytical method for separation and identification of Naja haje snake venom components, known for its neurotoxic activity. In addition, we wanted to find out if crude snake venom could inhibit the development of both Gram-positive and Gram-negative bacterial cultures. Materials and Method: Analysis of venom was performed on a HPLC system using a C16 column with UV detection at 210 nm. The analysis was done using two mobile phases, containing different concentrations of acetonitrile and trifluoroacetic acid aqueous solution at different pH values. An elution gradient was set at a flow of 0.60 mL/min. Bactericidal activity was quantified by measuring inhibition diameter around an aseptically disk filled with crude venom using Staphylococcus aureus and Escherichia coli. Results: An optimal HPLC analytical method has been developed by changing different parameters such as the pH value of mobile phase A or the elution gradient. The best resolution were obtained at a pH value of 7.4, in gradient varying from 5% to 45% in mobile phase B. Microbiological studies of the venom showed that Gram-positive bacteria growth was inhibited by crude venom, while on Gram-negative bacteria growth no effect was observed. Inhibition zone is dose-dependent and fresh crude venom is with 30% more potent than venom freeze and kept at -55°C. Conclusions: A comprehensive catalog of venom composition may serve as a starting point for studying structurefunction correlations of individual toxins for the development of new research tools and drugs of potential clinical use.

Open access

Hajnal Kelemen, Gabriel Hancu, Serban Andrei Gâz-Florea, Eniko Nemes-Nagy, Lajos Attila Papp and Eleonora Mircia

Abstract

Objective: Miconazole, an imidazole antifungal derivative, is a very hydrophobic compound, a major drawback in obtaining topical pharmaceutical formulations with optimal bioavailability. Cyclodextrins (CDs) may increase local drug delivery by enhancing the drug release and/or permeation. The aim of the study is the characterization of inclusion complexes between miconazole and different CD derivatives.

Methods: Several CD derivatives were tested in the experiments. The binary systems between miconazole and different CDs were prepared in 1:1 molar ratios by physical-mixture and kneading methods. Differential scanning calorimetry (DSC) and Fourier transformed-infrared spectroscopy (FT-IR) methods were used to characterize solid state interactions between miconazole and CDs in their binary systems.

Results: The FT-IR analysis suggests the formation of a new solid phase, indicating a molecular interaction between the components. The DSC analysis sustains the hypothesis of formation of partial inclusion complexes between miconazole nitrate and CD.

Conclusion: The thermic behaviour of the complexes depends both on the preparation method and the composition of the products.

Open access

Mircea Dumitru Croitoru, Hermina Iulia Petkes, Ibolya Fülöp, Remus Cotârlan, Oana Elena Şerban, Titica Maria Dogaru, Şerban Andrei Gâz Florea, Béla Tőkés and Cornelia Majdik

Abstract

Free radicals are involved in the development of reperfusion injuries. Using a spin trap, the intensity of such lesions can be reduced. Nitrones (effective in vivo spin traps) were tried in this work as in vivo nitric oxide donors. Nitrite and nitrate concentration values (rabbit blood) were used as biomarkers of nitric oxide production. Most nitrones did not increase plasma concentrations of nitrite and nitrate; on the contrary, reduced plasma concentrations of these indicators were noted. However, glyoxal isopropyldinitrone, in a dose of 50 mg kg-1, was highly effective in increasing nitric oxide production. At the same time, nitrones do not react with hepatic homogenates, proving that the release of nitric oxide takes place in the tissues and is not related to hepatic metabolism. Before using nitrones in vivo, they were tested in vitro for the ability to release nitric oxide following a reaction with the hydroxyl radical.