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1.
Int J Pharm ; 625: 122106, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36029993

RESUMO

Nanofibers (NFs) provide several delivery advantages like their great flexibility and similarity with extracellular matrix (ECM) which qualify them to be the unique model of a wound dressing. NFs could create mats of polymeric matrix loaded with an active agent enhancing its solubility and stability. In our study, Gentiopicroside (GPS) and Thymoquinone (TQ) loaded in NFs polymeric mats composed of coblended polyvinyl pyrrolidine (PVP) and methyl ether Polyethylene glycol (m-PEG) were fabricated via electrospinning technique. A morphological study using Scanning Electron Microscopy (SEM) was performed for all formulae as well as in vitro release study using High-performance Liquid chromatography (HPLC) for sample analysis. The optimized formula (F3) was chosen for further assays using Fourier-Transform Infrared Spectroscopy (FTIR), and Differential Scanning Calorimetry (DSC). Study of the antibacterial effect, and in vivo healing action for diabetic infected wounds to quantify Tumor necrosis factor-alpha and Cyclooxygenase-2 were also investigated. F3 achieved the highest % cumulative release (99.79 ± 6.47 for GPS and 96.89 ± 6.87 for TQ) at 60 min, and a smaller diameter (200 nm) showing significant anti-bacterial effects with well-organized skin architecture demonstrating great healing signs. Our results revealed that m-PEG/PVP NFs mats loaded with GPS and TQ could be considered an optimal wound care dressing.


Assuntos
Diabetes Mellitus Experimental , Éteres Metílicos , Nanofibras , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bandagens , Benzoquinonas , Diabetes Mellitus Experimental/tratamento farmacológico , Glucosídeos Iridoides , Nanofibras/química , Polietilenoglicóis , Polímeros/química , Polivinil , Pirrolidinas , Ratos
2.
Pak J Pharm Sci ; 34(1(Supplementary)): 337-343, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34275859

RESUMO

Most clinical investigations about the impact of nanoparticles on cells and tissues show that nanoparticles may enter the human body by means of respiratory tracts. Humans, animals, plants and environments are continually presented to a wide scope of business items containing silver nanoparticles (Ag NPs) in their piece. Ag NPs, utilized in various consumer products as room showers, surface cleaners, wound dressings, food storage containers and many textiles. The current examination planned to explore the defensive role of Avenanthramide-C (Avns) contrary to the lung toxicity initiated by Ag NPs injection in rats. 40 male Wistar rats were separated into 4 groups (Gp1, control; Gp2, Avns; Gp3, Ag NPs; Gp4, Ag NPs+Avns). Current results revealed that; Ag NPs induced a significant depletion in RBCs count, hemoglobin, platelets counts and a significant increase in total WBCs, lung injury, cyclooxygenase-2 (COX2) and TNFα expressions as compared to control. Treatments of Ag NPs with Avenanthramide-C extract (Ag NPs+Avns) improved the lung structure and blood complete pictures as compared to Ag NPs group.


Assuntos
Células Sanguíneas/efeitos dos fármacos , Lesão Pulmonar/patologia , Pulmão/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Prata/efeitos adversos , ortoaminobenzoatos/farmacologia , Animais , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Contagem de Eritrócitos , Hematócrito , Hemoglobinas/efeitos dos fármacos , Hemoglobinas/metabolismo , Contagem de Leucócitos , Pulmão/patologia , Lesão Pulmonar/induzido quimicamente , Contagem de Plaquetas , Ratos , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-25064505

RESUMO

Metal complexes of the chloride, nitrate and acetate salts of Co(II), Ni(II) Cu(II), Zn(II), Cd(II) or Hg(II) with 2,3-butanedione bis(isonicotinylhydrazone) [BBINH] have been synthesized and structurally characterized. The crystal of BBINH was solved to crystallize as monoclinic system with space group of P121/c14. The formulae of the complexes were assigned based on the elemental analysis and mass spectra. The formation of BBINH complexes depend on the metal anion used. All complexes are nonelectrolytes except for the complexes 2, 3, 4 are (1:1) and 13 and 14 which are 1:2 electrolytes. BBINH behaves as a neutral tetradentate (N2O2) in the chloride complexes of Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II). In [Co2(BBINH)(H2O)Cl3]Cl⋅H2O, BBINH has the same dentate but with the two Co(II) ions. In the acetate complexes, [Ni2(BBINH-2H)(H2O)2(OAc)2]⋅3H2O and [Cu2(BBINH-2H)(OAc)2]⋅5H2O, BBINH acts as a binegative tetradentate with the two metal ions. The ligand in the nitrate complexes acts as a neutral bidentate via the two hydrazone azomethine C=NHy; the nitrate ions are ionic in the Cd(II) and Zn(II) complexes and covalent in the Ni(II) complex. The data are supported by NMR ((1)H and (13)C) spectra. The magnetic moments and electronic spectra of all complexes provide tetrahedral, square planar and/or octahedral structure. The decomposition of the complexes revealed the outer and inner solvents as well as the remaining residue based on TGA. The complexes have variable activities against some bacteria and fungi. The ligand is inactive against all tested organisms. The activity of Cd(II) and Hg(II) may be related to the geometry of the complexes.


Assuntos
Complexos de Coordenação/farmacologia , Hidrazonas/química , Hidrazonas/farmacologia , Elementos de Transição/farmacologia , Bactérias/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Complexos de Coordenação/química , Cristalografia por Raios X , Elétrons , Fungos/efeitos dos fármacos , Ligantes , Fenômenos Magnéticos , Testes de Sensibilidade Microbiana , Peso Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Infravermelho , Termogravimetria , Temperatura de Transição
4.
Am J Physiol Heart Circ Physiol ; 280(6): H2639-48, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356620

RESUMO

The interventricular septum, which flattens and inverts in conditions such as pulmonary hypertension, is considered by many to be an unstressed membrane, in that its position is assumed to be determined solely by the transseptal pressure gradient. A two-dimensional finite element model was developed to investigate whether compression and bending moments (behavior incompatible with a membrane) exist in the septum during diastole under abnormal loading, i.e., pulmonary artery (PA) constriction. Hemodynamic and echocardiographic data were obtained in six open-chest anesthetized dogs. For both control and PA constriction, the measured left ventricular and right ventricular pressures were applied to a residually stressed mesh. Adjustments were made to the stiffness and end-bending moments until the deformed and loaded residually stressed mesh matched the observed configuration of the septum. During PA constriction, end-bending moments were required to obtain satisfactory matches but not during control. Furthermore, substantial circumferential compressive stresses developed during PA constriction. Such stresses might impede septal blood flow and provoke the unexplained ischemia observed in some conditions characterized by abnormal septal motion.


Assuntos
Septos Cardíacos/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Modelos Cardiovasculares , Disfunção Ventricular Direita/fisiopatologia , Animais , Pressão Sanguínea , Simulação por Computador , Diástole , Modelos Animais de Doenças , Cães , Ecocardiografia , Feminino , Análise de Elementos Finitos , Septos Cardíacos/diagnóstico por imagem , Hemodinâmica , Masculino , Artéria Pulmonar , Estresse Mecânico , Disfunção Ventricular Direita/diagnóstico por imagem
5.
Artigo em Inglês | MEDLINE | ID: mdl-11328642

RESUMO

The interventricular septum is the structure that separates the left and right ventricles of the heart. Under normal loading conditions, it is concave to the left ventricle, but under abnormal loading the septum flattens and occasionally inverts. In the past, the septum has frequently been modelled as integral to the left ventricle with the effects of pressure from the right ventricle being ignored. Under abnormal loading, the septum has been described as behaving equivalent to a "flapping sail". There has been no consideration of structural behaviour under these conditions. A 2-D plane stress FE model of the septum was used to investigate the difference in structural behaviour of the septum during diastole between normal and abnormal loading. The biaxial stress patterns that develop are distinctively disparate. Under normal loading, the septum behaves much like a thick-walled cylinder subject to internal and external pressure, with the resulting stresses being circumferential tension and radial compression, both varying with radius. These stresses are very low throughout most of diastole. However, under abnormal loading, the septum behaves in an arch-like fashion, with high compressive stresses almost circumferential in direction, combined with radial compression. We conclude that right ventricular pressures cause bending effects in the wall of the heart, and that under abnormal loading, the compressive stresses that develop in the septum may lead to an understanding of certain, previously unexplained, pathological conditions.


Assuntos
Simulação por Computador , Septos Cardíacos/fisiologia , Modelos Cardiovasculares , Força Compressiva , Circulação Coronária/fisiologia , Diástole/fisiologia , Septos Cardíacos/anatomia & histologia , Septos Cardíacos/fisiopatologia , Humanos , Modelos Anatômicos , Pressão , Estresse Mecânico , Resistência à Tração
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