MARA TANIA SILVA ALCANTARA

MARA TANIA SILVA ALCANTARA

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Efeito do CMC no intumescimento de curativos de hidrogel à base de PVP com nanoprata
2019 - ALCANTARA, M.T.S.; OLIVEIRA, M.J.A.; LIERMANN, G.M.; LUGAO, A.B.
Hidrogéis de PVP são redes poliméricas tridimensionais, hidrofílicas, que apresentam propriedades de intumescimento e biocompatibilidade o que favorece seu uso como curativos. Por propiciar umidade no leito da ferida mantém o ambiente ideal para cicatrização, além de não aderir a ela. Por outro lado as nanopartículas de prata apresentam propriedades antimicrobianas e antiinflamatórias e o uso de radiação ionizante permite a reticulação e esterilização simultânea do curativo. O objetivo deste estudo foi avaliar o efeito do CMC no intumescimento de curativos de hidrogel com 22 e 80 ppm de nanopartículas de prata, reticulado por radiação ionizante, assim como avaliar a resistência mecânica dos curativos estudados. Os curativos foram avaliadas a partir de ensaios de fração gel, intumescimento e resistência mecânica. Os resultados indicaram um aumento importante no intumescimento do curativo com a adição de CMC, principalmente para o curativo com maior concentração de nanoprata, porém um menor grau de reticulação e consequentemente redução da sua resistência mecânica.
Simultaneous hydrogel crosslinking and silver nanoparticle formation by using ionizing radiation to obtain antimicrobial hydrogels
2019 - ALCANTARA, M.T.S.; LINCOPAN, N.; SANTOS, P.M.; RAMIREZ, P.A.; BRANT, A.J.C.; RIELLA, H.G.; LUGAO, A.B.
Hydrogel dressings are crosslinked hydrophilic polymers able of swelling in presence of water and can be used in many different types of wound care. In turn, in wound care, silver has been used for a long time as an effective antimicrobial agent. Recent studies have demonstrated an increase of its antimicrobial action when it is used at nanometer scale, that is, as silver nanoparticles (AgNPs), which have anti-inflammatory effect on infected wounds, rashes, and mesh skin grafts. The objective of this work was to study hydrogel dressings containing AgNPs from silver nitrate, synthesized by radiation involving the formation of silver nanoparticles with simultaneous occurrence of crosslinking and sterilization of the polymer systems. One of the hydrogels was prepared with poly(N-vinyl-2- pyrrolidone) (PVP) and the other with poly(vinyl alcohol) (PVA) as main studied polymers. An aqueous solution of AgNO3 was added to both polymer systems separately. The AgNPs synthesis, polymer crosslinking and dressing sterilization were achieved simultaneously by irradiating the resultant solutions with gamma-rays from a 60Co source. Gel fraction, swelling in reverse osmosis water, SEM-EDS, UVvisible spectroscopy, and antimicrobial activity were performed and characterized. The obtained results showed that the dressings have a soft consistency, high degree of crosslinking and swelling, homogeneous distribution of AgNPs with peaks of plasmonic bands about 400 nm, but only PVP hydrogel showed antimicrobial properties to P. aeruginosa and normal S. aureus. Moreover, this hydrogel also showed antimicrobial properties to S. aureus strain multiresistant to penicillins, cephalosporins, carbapenems, sulfonamides, tetracyclines, quinolones, and aminoglycosides, whereas the PVA hydrogel showed antimicrobial properties to P. aeruginosa and bacteriostatic activity to S. aureus. The results suggest that both synthesized dressings have potential for use in wounds and burns infected with gram-positive and gram-negative bacteria.
Synthesis and in vivo behavior of PVP/CMC/agar hydrogel membranes impregnated with silver nanoparticles for wound healing applications
2018 - LIMA, GABRIEL G. de; LIMA, DARLLA W.F. de; OLIVEIRA, MARIA J.A. de; LUGAO, ADEMAR B.; ALCANTARA, MARA T.S.; DEVINE, DECLAN M.; SA, MARCELO J.C. de
The field of wound healing has seen an increase in research activity in wound care and hydrogel-based dressings have been targeted as a solution for these applications. Hydrogels with silver nanoparticles can present many advantages for this field. However, if the aggregation and sterilization of this product have not been carefully considered, the effectiveness or use could be limited. Therefore, in the current study, a hydrogel-based wound dressing membrane was developed using polyvinylpyrrolidone (PVP), polyethylene glycol (PEG), agar, and carboxymethyl cellulose (CMC). Silver ions (Ag+) were dispersed in the polymer matrix and its reduction with formation of a hydrogel and silver nanoparticles was performed using 60Co gamma irradiation to enhance the dressings antimicrobial properties. The resulting hydrogel presented a high degree of swelling and a good size control of silver nanoparticles. The incorporation of AgNPs was confirmed via Raman spectroscopy and the samples presented no signs of toxicity in vitro as assessed using an elution assay with neutral red uptake as the cytotoxic end point. Membranes were tested in vivo using a full thickness defeat model in rabbits. Postmortem histopathological analysis indicated that the use of the hydrogel membranes that incorporated AgNPs had a stimulatory action on wound healing as evidenced by a high intensity of fibroblasts and neovascularization in the tissue, which promoted a faster healing process when compared to the untreated wounds. We demonstrate the possibility of producing a hydrogel with good size control of AgNPs, which can also be directly sterilized within the formation of this material via gamma irradiation. Furthermore, the mechanism of hydrogel healing, in vivo, with silver nanoparticles was found to have a direct correlation of silver nanoparticles with in vitro cell results.
Effect of gamma irradiation on polymeric gel with glucantime and silver for the alternative treatment of cutaneous leishmania
2018 - OLIVEIRA, M.J.A.; VASQUEZ, P.A.S.; ALCANTARA, M.T.S.; LUGAO, A.B.
The drugs used to treat leishmania are in injectable form and the applications are painful that many patients give up during the treatment. The treatment requires hospitalization to monitor the side effects caused by the drugs, such as cardiac arrhythmia, renal dysfunction, among others. In addition to this situation, if the patient has symptoms such as cardiac arrhythmia, renal dysfunction they can not make use of the treatment. For these reasons finding new forms of treatments with minor side effects as alternative treatments for leishmaniasis has been the object of study of many research laboratories. The objective of this work was to analyze the effects of gamma irradiation on polymeric gel with glucantime and silver as the alternative treatment of cutaneous leishmania. In this case, the polymeric gel prevents the drug from falling directly into the bloodstream, avoiding the side effects, which would make unnecessary the patient's hospitalization. For the development of the gels was used, alginate, polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), laponite clay, silver ions, and glucantime. The cobalt-60 source gamma irradiation was used for gel formation, silver nanoparticles and simultaneous sterilization. The physico-chemical characterizations were elemental analysis for quantification of Sb(V) and Sb(III) antimoniate, infrared spectroscopy (FTIR), dispersive energy spectrometry (EDS), transmission electron microscope (TEM). The results are promising, they show that the irradiation does not interfere with the drug's active principle, as expected in this study.
Hydrogels with silver nanoparticles for wound treatment
2017 - OLIVEIRA, MARIA J.A.; SANTOS, JONNATAN J.; TOMA, SERGIO H.; ALCANTARA, MARA T.S.; VASQUEZ, PABLO A.V.; ARAKI, KOITI; LUGAO, ADEMAR B.
In recent years, the study and preparation of nanoparticles have attracted considerable interest for both fundamental and applied research. In biomedical area, silver nanoparticles have been a vast field of study, although antimicrobial properties have originated from their medical application since 19th century. Since silver has had several uses and its enormous potential for the treatment of injuries. Silver-containing topcoats are an excellent option for topical microbial combat on wounds that present infection, as well as being an essential tool for controlling bacterial load. Among these coatings are the hydrogel dressings with silver nanoparticles that have broad spectrum of antimicrobial action. In vitro studies have demonstrated bactericidal activity in strains of antibiotic resistant microorganisms. The objective of this work is characterize hydrogels with silver nanoparticles, prepared using polyvinylpyrrolidone (PVP), carboxymethylcellulose (CMC), used to treat wounds. A gamma radiation source cobalt-60 was used to crosslink the hydrogels, sterilize and form the silver nanoparticles simultaneously. Irradiation is recognized as a very viable tool because there is no need to add possibly harmful primers or crosslink that are difficult to remove. The results showed uniform distribution of the nanoparticles on the surface of the hydrogels, making it feasible for topical application.
Obtaining of a hydrogel gel dressing of PVP with nanosilver for deep and complex wounds
2017 - ALCANTARA, MARA T.S.; COUTINHO, CAMILA M.; OLIVEIRA, MARIA J.A.; MUNHOZ, MARA M.L.; LUGAO, ADEMAR B.
Introduction Chronic and some acute wounds of difficult treatment that challenge medical and nursing teams are classificadas como Complex wound (Ferreira et al., 2006). Due to the long cicatrization time and successive relapses, cause a problem social on patients' lives and economic a major impact on the health system (Azoubel et al., 2017). Throughout the world there has been a growing interest in the use of hydrogels for application as dressings in view that they are able to maintain the humidity of the wound, favoring the epithelialization of lesions and favoring the relief of pain. On the other hand, silver is an agent that has been used since ancient times, but it has been replaced after the discovery of antibiotics. However, with the advent of bacterial resistance to antibiotics and the development of nanotechnology, it has regained notoriety, since the clinical incidence of silver resistance remains low (Chopra, 2007).In addition to its bactericidal properties, silver nanoparticles (AgNPs) also have anti-inflammatory properties, which, allied to hydrogels’ advantages of maintaining moisture in the wound, represent a great advantage for use as a dressing. However, conventional dressings do not address the need for direct contact with the wound when this is a deep wound. The objective of this work was to obtain a hydrogel gel with silver nanoparticles for wound dressing, synthesized in situ by using ionizing radiation for gelation (crosslinking of PVP-Ag+ aqueous solution), synthesis of the AgNPs and simultaneous sterilization of the final product, able to fill the cavity of deep wounds, thus allowing the direct contact of the dressing with the lesioned walls. Methodology The gel was prepared from the mixture of PVP with plasticizers, water, and silver ions; next, the mixture was irradiated / sterilized by gamma-irradiation from a 60-Co source at a dose of 20 kGy. . Results The result of this work is a viscous and transparent gel (Fig. 1), easy to be applied, able to control pain since it reduces the local temperature due to evaporation of water. Fig. 1 - Hydrogel gel of PVP with silver nanoparticles for wound dressing. The studies are being continued with the aim of evaluating its stability and bactericidal activity.
Effect of gamma radiation on polyvinylpyrrolidone hydrogels
2017 - OLIVEIRA, M.J.A.; VASQUEZ, P.A.S.; ALCANTARA, M.T.S.; MUNHOZ, M.M.L.; LUGAO, A.B.
Polyvinylpyrrolidone (PVP) hydrogels have been investigated as drug delivery matrices for the treatment of wounds, such as cutaneous leishmaniasis, and matrices with silver nanoparticles for chronic wounds and burns. The preparation of such hydrogels can occur by various cross-linking methods, such as gamma, chemical, physical, among others. The most feasible for wound dressings is gamma irradiation from cobalt-60, because gamma irradiation simultaneously promotes crosslinking and sterilization, leaving the wound dressing ready for use. The objective of this work was to investigate the effect on physico- chemical properties of gamma radiation on PVP hydrogel according to the radiation absorbed dose variation. The PVP hydrogels were irradiated with doses of 5, 15, 25, 35, 45, 55, 65, 75 and 95kGy at dose rate of 5 kGy/h and characterized by swelling, thermogravimetric and mechanical analysis. Results shown a favorable dose range window for processing of these hydrogels related to the application. The results showed that mechanical strength was affected at doses starting at 25 kGy.
Influence of gamma radiation on anphotericin b to possible incorporation into wound dressing
2016 - OLIVEIRA, M.J.A.; ESTRADA-VILLEGAS, G.M.; VASQUEZ, P.A.S.; ALCANTARA, M.T.S.; LUGAO, A.B.
In recent decades, many investigations have been addressed to develop alternative non–conventional treatments for several human body burns and wounds as well as new drug delivery systems in the treatment of diseases such as cutaneous leishmaniasis, always aiming to improve the quality of life of patients. Amphotericin B (Amph-B) is an antifungal drug often used intravenously for serious leishmaniasis treatment, but is well known for its severe and potentially lethal side effects. Hydrogels wound-dressing containing (Amph-B) will be able to offer an alternative to some patients that cannot be treated by conventional treatment due to (Amph-B) side effects. Many is these hydrogels are produced by gamma radiation in a simultaneous sterilization and cross-linking process. The hydrogels are useful as a wound-dressings, because they hold the wound moisture, are good as a drug delivery system and low cost production. The aim of this work is show the effects of gamma radiation (60 Cobalt) into (Amph-B) at different irradiation dose (10 kGy, 15kGy and 20kGy) and different temperatures (25ºC, 0ºC and -70ºC) to find the optimum conditions for future incorporation into hydrogels as an alternative treatment of cutaneous leishmaniasis. The study is very important to evaluate the molecule behavior when irradiated. The drug stability will be characterized by High Performance Liquid Cromatography (HPLC), UV-vis and Nuclear Magnetic Ressonance (NMR).
Hydrogel de PVP/CMC e nanoparticulas de prata
2015 - MUNHOZ, MARA M.L.; OLIVEIRA, MARIA J.A.; ALCANTARA, MARA T.S.; LINHARES, KAMILA P.; ROGERO, SIZUE O.; LUGAO, ADEMAR B.
Hidrogel polimérico com alginato e AgNP para tratar e absorver exudato de feridas
2015 - LINHARES, KAMILA P.; OLIVEIRA, MARIA J.A.; ALCANTARA, MARA T.; MUNHOZ, MARA M.L.; LUGAO, ADEMAR B.