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111.
gota Pet Dra Ksa dm Haimhoffer Dniel Nemes Plma Fehr Zoltn Ujhelyi Mikls Vecsernys Judit Vradi Ferenc Fenyvesi Adina Frum Felicia Gabriela Gligor Laura Graiela Vica Eleonora Marian Tunde Jurca Annamaria Pallag Mariana Eugenia Muresan Zoltn Tth Ildik Bcskay 《Molecules (Basel, Switzerland)》2022,27(9)
Philadelphus coronarius is a versatile plant and its use in folk medicine has a long tradition; however, scientifically, the medical utilization of the herb is a less explored research field. The aim of our study was to identify and determine the quantity of the bioactive compounds of both the leaf and the flower and prepare a lyophilized product of them, from which medical ointments were formulated, since the topical application of P. coronarius has also not been studied. In vitro drug release, texture analysis and biocompatibility experiments were carried out, as well as the investigation of microbiological, antioxidant and anti-inflammatory properties. According to our results the composition and the selected excipients of the ointments have a great impact on the drug release, texture and bioavailability of the preparation. During the microbiological testing, the P. coronarius leaf was effective against Escherichia coli and Staphylococcus aureus, but it did not significantly decrease IL-4 production when it was tested on HaCaT cells. P. coronarius is a promising herb, and its topical application in antimicrobial therapy can be a useful addition to modern medical therapy. 相似文献
112.
Adina Graziella Anghelescu-Dogaru Gabrielle Charlotte Chitanu Heikki Tenhu 《Macromolecular Symposia》2006,239(1):68-76
One of the present trends to increase the efficiency of the chrome tanning process is the use of chemicals which change the affinity and induce a better binding of the chromium ions in the hides. Recently, some anionic polyelectrolytes based on poly(acrylic acid) or maleic acid copolymers were developed as additives in the chrome tanning. The effect of polyelectrolytes could be explained by their interaction with the collagen from hide. In our work four maleic acid copolymer/collagen systems were investigated by turbidimetric, conductometric and potentiometric titrations. The interaction between the two macromolecular compounds was clearly evidenced, and its dependence on the chemical structure of the maleic acid copolymer and on the amount of added chromium ions was studied. Homogeneous systems or turbid dispersions were observed depending on the hydrophilic or hydrophobic character of the maleic copolymer, on the [CH]/[MP] ratio, and on the concentration of the chromium ions. 相似文献
113.
Diana Larisa Roman Denisa Ioana Voiculescu Mariana Adina Matica Victor Baerle Marioara Nicoleta Filimon Vasile Ostafe Adriana Isvoran 《Molecules (Basel, Switzerland)》2022,27(19)
Triticonazole is a fungicide used to control diseases in numerous plants. The commercial product is a racemate containing (R)- and (S)-triticonazole and its residues have been found in vegetables, fruits, and drinking water. This study considered the effects of triticonazole on soil microorganisms and enzymes and human health by taking into account the enantiomeric structure when applicable. An experimental method was applied for assessing the effects of triticonazole on soil microorganisms and enzymes, and the effects of the stereoisomers on soil enzymes and human health were assessed using a computational approach. There were decreases in dehydrogenase and phosphatase activities and an increase in urease activity when barley and wheat seeds treated with various doses of triticonazole were sown in chernozem soil. At least 21 days were necessary for the enzymes to recover the activities. This was consistent with the diminution of the total number of soil microorganisms in the 14 days after sowing. Both stereoisomers were able to bind to human plasma proteins and were potentially inhibitors of human cytochromes, revealing cardiotoxicity and low endocrine disruption potential. As distinct effects, (R)-TTZ caused skin sensitization, carcinogenicity, and respiratory toxicity. There were no significant differences in the interaction energies of the stereoisomers and soil enzymes, but (S)-TTZ exposed higher interaction energies with plasma proteins and human cytochromes. 相似文献
114.
Ancua Ctlina Fia Ana Andreea Secreanu Adina Magdalena Musuc Emma Adriana Ozon Iulian Sarbu Irina Atkinson Adriana Rusu Erand Mati Valentina Anuta Anca Lucia Pop 《Molecules (Basel, Switzerland)》2022,27(19)
The present study aims to demonstrate the influence of the polymer-carrier type and proportion on the quality performance of newly developed oral immediate-release tablets containing amiodarone solid dispersions obtained by hot-melt extrusion. Twelve solid dispersions including amiodarone and different polymers (PEG 1500, PEG 4000; PEG 8000, Soluplus®, and Kolliphor® 188) were developed and prepared by hot-melt extrusion using a horizontal extruder realized by the authors in their own laboratory. Only eleven of the dispersions presented suitable physical characteristics and they were used as active ingredients in eleven tablet formulations that contain the same amounts of the same excipients, varying only in solid dispersion type. The solid dispersions’ properties were established by optical microscopy with reflected light, volumetric controls and particle size evaluation. In order to prove that the complex powders have appropriate physical characteristics for the direct compression process, they were subjected to different analyses regarding their flowability and compressibility behavior. Additionally, the Fourier transform infrared spectroscopy and X-ray diffraction analysis were performed on the obtained solid dispersions. After confirming the proper physical attributes for all blends, they were processed into the form of tablets by direct compression technology. The manufactured tablets were evaluated for pharmacotechnical (dimensions–diameter and thickness, mass uniformity, hardness and friability) and in vitro biopharmaceutical (disintegration time and drug release) performances. Furthermore, the influence of the polymer matrix on their quality was determined. The high differences in flow and compression performances of the solid dispersions prove the relevant influence of the polymer type and their concentration-dependent plasticizing properties. The increase in flowability and compressibility characteristics of the solid dispersions could be noticed after combining them with direct compression excipients owning superior mechanical qualities. The influence of the polymer type is best detected in the disintegration test, where the obtained values are quite different between the studied formulations. The use of PEG 1500 alone or combined in various proportions with Soluplus® leads to rapid disintegration. In contrast, the mixture of PEG 4000 and Poloxamer 188 in equal proportions determined the increase in disintegration time to 120 s. The use of Poloxamer 188 alone and a 3:1 combination of PEG 4000 and Soluplus® also generates a prolonged disintegration time for the tablets. 相似文献
115.
Lucica Viorica Ababei Angela Kriza Adina Magdalena Musuc Cristian Andronescu Elena Adina Rogozea 《Journal of Thermal Analysis and Calorimetry》2010,101(3):987-996
New complexes of 2-benzoyl-pyridil-isonicotinoylhydrazone (L) with Cu(II), Co(II), Ni(II) and Mn(II), having formula of type
[ML2] SO4·xH2O (M = Cu2+, Co2+, Ni2+, x = 2 and M = Mn2+, x = 3), have been synthesised and characterised. All complexes were characterised on the basis of elemental analyses, IR spectroscopy,
UV–VIS–NIR, EPR, as well as thermal analysis and determination of molar conductivity and magnetic moments. The thermal behaviour
of complexes was studied using thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry
(DSC). The structure of L hydrazone was established by X-ray study on single crystal. The ligand works as tridentate NNO,
being coordinated through the azomethine nitrogen, the pyridine nitrogen and carbonylic oxygen. Heats of decomposition, ΔH, associated with the exothermal effects were also determined. 相似文献
116.
Angela Kriza Mariana Loredana Dianu Cristian Andronescu Adina Elena Rogozea Adina Magdalena Musuc 《Journal of Thermal Analysis and Calorimetry》2010,100(3):929-935
New copper (II) complexes of Schiff bases with 1,2-di(imino-2-aminomethylpyridil)ethane with the general composition CuLX m (H2O) x , [L = Schiff base, X = Cl?, Br?, NO3 ?, ClO4 ?, CH3COO?, m = 2; X = SO4 2?, m = 1] were prepared by template synthesis. The complexes were characterized by elemental analysis, conductivity measurements, magnetic moments, IR, UV–VIS and EPR spectra. The thermal behavior of complexes was studied using thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Infrared spectra of all complexes are in good agreement with the coordination of a neutral tetradentate N4 ligand to the cooper (II) through azomethinic and pyridinic nitrogen. Magnetic, EPR and electronic spectral studies show a monomeric distorted octahedral geometry for all Cu(II) complexes. Conductance measurements suggest the non-electrolytic nature of the compounds, except for copper (II) nitrate and perchlorate complexes which are 1:2 electrolytes. Heats of decomposition, ΔH, associated with the exothermal effects were also determined. 相似文献
117.
Adina Rotar Richard A. Varga Klaus Jurkschat Cristian Silvestru 《Journal of organometallic chemistry》2009,694(9-10):1385-1392
Hypercoordinated diorganotin(IV) dichloride, [2-(Et2NCH2)C6H4]2SnCl2 (1), was prepared by reacting [2-(Et2NCH2)C6H4]Li with SnCl4. Halide-exchange reactions between 1 and the appropriate potassium halides gave [2-(Et2NCH2)C6H4]2SnX2 [X = F (2), Br (3), I (4)]. Reaction of 1 with excess of Na2S gave the cyclo-[{2-(Et2NCH2)C6H4}2SnS]2 (5). The solution behavior of the title compounds in solution was investigated by multinuclear (1H, 13C, 19F and 119Sn) NMR spectroscopy, including variable temperature studies. Single-crystal X-ray diffraction analysis revealed for all compounds intramolecular N → Sn coordination thus resulting in distorted octahedral (C,N)2SnX2 configurations. Planar chirality is observed as result of the non-planarity of the SnC3N rings; all compounds, however, crystallizing as racemates. The isomers are linked by extensive hydrogen bonds to give different supramolecular architectures in the crystals of compounds 1, 3 and 4. 相似文献
118.
In this paper, we study stability properties of hypersurfaces with constant weighted mean curvature (CWMC) in gradient Ricci solitons. The CWMC hypersurfaces generalize the f-minimal hypersurfaces and appear naturally in the isoperimetric problems in smooth metric measure spaces. We obtain a result about the relationship between the properness and extrinsic volume growth under the assumption of a limitation for the weighted mean curvature of the immersion. Moreover, we estimate Morse index for CWMC hypersurfaces in terms of the dimension of the space of parallel vector fields restricted to hypersurface. 相似文献
119.
We investigate proper biharmonic hypersurfaces with at most three distinct principal curvatures in space forms. We obtain the full classification of proper biharmonic hypersurfaces in 4‐dimensional space forms (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
120.