MARIA JOSE ALVES DE OLIVEIRA

MARIA JOSE ALVES DE OLIVEIRA

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Gamma and electron beam irradiation effects for conservation treatment of cellulose triacetate photographic and cinematographic films
2021 - NAGAI, MARIA L.E.; SANTOS, PAULO de S.; OTUBO, LARISSA; OLIVEIRA, MARIA J.A.; VASQUEZ, PABLO A.S.
Photographic and cinematographic films of cellulose triacetate safeguarded in historical and cultural institutions are often contaminated by fungi when stored in inadequate conditions of humidity and temperature. The presence of fungi affects the image contained in the films, accelerates the process of biodeterioration and represents a risk to the health of people working with contaminated materials. In addition, another common physicochemical degradation affecting cellulose triacetate films causing deacetylation of polymer chain is called “vinegar syndrome”. Considering the dose interval established for the disinfection of cultural heritage materials, in this work the effects of irradiation with gamma rays and electron beam on photographic and cinematographic films of cellulose triacetate were evaluated. Additionally, the thermal stability behavior of the films and the feasibility of crosslinking of CTA films were investigated. Film samples were selected and characterized by FTIR-ATR spectroscopy. Irradiated samples by gamma rays and electron beam with radiation absorbed doses between 6 kGy and 200 kGy were examined by FEGSEM microscopy, UV–Vis spectrophotometry and differential scanning calorimetry (DSC). The results showed that disinfection by gamma and electron beam irradiation, in the dose range of 6 kGy–10 kGy, does not change or modification of main properties of the constitutive materials of photographic and cinematographic films. The applied dose of 50 kGy, both gamma rays and electron beam, indicated a crosslinking effect on the films and can be considered a possibility for the treatment of films affected by the “vinegar syndrome”.
Influence of gamma radiation on Amphotericin B incorporated in PVP hydrogel as an alternative treatment for cutaneous leishmaniosis
2021 - OLIVEIRA, MARIA J.A. de; VILLEGAS, GETHZEMANI M.E.; MOTTA, FLAVIA D.; FABELA-SANCHEZ, OMAR; ESPINOSA-ROA, ARIAN; FOTORAN, WESLEY L.; PEIXOTO, JANAINA C.; TANO, FABIA T.; LUGAO, ADEMAR B.; VASQUEZ, PABLO A.S.
Amphotericin B (Amph-B) is an antifungal drug used intravenously for the treatment of leishmaniasis. Side-effects from Amph-B treatment can arise such as cardiac arrhythmia and renal dysfunctions, which will lead to discontinuation of treatment. Unfortunately, patients in endemic countries do not have access to alternative therapies. The objective of this study was to analyze the effects of Cobalt-60 gamma irradiation on crosslinking polymeric hydrogels (Hydg) and the incorporation of Amph-B into the gel as a controlled-release drug delivery alternative. Polyvinylpyrrolidone (PVP)/Amph-B solutions were irradiated with 15 kGy at 0 °C and 25 °C. The drug's stability was ascertained by UV–visible spectrometry, liquid chromatography/mass spectrometry and proton nuclear magnetic resonance. Irradiated Hydg/Amph-B achieved similar stability to the standard Amph-B solution and was enough to promote hydrogel crosslinking. In vitro trials were carried out to ensure Amph-B was still biologically active after irradiation. The results from flow cytometry and MTT assay show that Amph-B had an IC50 = 16.7 nM. A combination of Hydg at 1.324 gmL−1 and Amph-B at 25.1 nM for 24 h lead to the greatest inhibition of L. amazonensis promastigotes, and could be used as an alternative treatment method for cutaneous leishmaniosis.
Effect of gamma radiation cobalt-60 on caffeine
2019 - MAIA, TIAGO C. dos S.; LUGAO, ADEMAR B.; AZOUBEL, ROBERTA; RAPOSO, MARCOS T.; OLIVEIRA, MARIA J.A. de
Objective: The objective of the study was to evaluate the effects of the incidence of gamma radiation of Cobalt-60 on caffeine. Material and Methods: The samples were studied in aqueous solution and powdered form after irradiation at doses: 2, 4, 8, 16 and 32 kGy by ionizing radiation source of 60Co. After wards, they were analyzed by differential scanning calorimetry (DSC), thermogravimetry (TG), and high performance liquid chromatography (HPLC). Results and Discussion: For the DSC technique no changes were observed in the curves after irradiation, which could witness changes in physicochemical properties after irradiation. The TG corroborated with the expected mass loss of caffeine, independent of the action of ionizing radiation. Furthermore, the results obtained by the chromatographic analysis did not show a percentage of caffeine degradation in the dose of the applied radiation when compared to the nonirradiated caffeine. Conclusion: In view of the results obtained, it was possible to observe the stability of caffeine on the influence of gamma radiation on the Cobalt-60 source.
Effectiveness of the hydrogel dressing crosslinked and sterilized by gamma radiation
2019 - GEMELLI, KARINE K.; SOUSA, GRAZIELLY M. de; GEMELLI, TIAGO F.; FERREIRA, OBEDE R.; OLIVEIRA, MARIA J.A. de; ALCANTARA, MARA T.S.; LUGAO, ADEMAR B.
Chronic wounds of difficult cicatrization are more incidents with an increased in life expectancy. The hydrogel with silver nanoparticles developed at the Nuclear Energetic Research Institute, crosslinked and sterilized by Gamma radiation, is inexpensive and has a simple manufacturing process that seems to be an alternative to the treatment of injuries. This experimental study compared the healing process of second intention of skin wounds of 4cm² on the back of 69 Wistar rats, considering the effectiveness of hydrogel dressings with silver nanoparticles. The animals were distributed in three groups that received treatment with hydrogel dressing, hydrogel with 22ppm of silver nanoparticles and hydrogel with 44ppm of silver nanoparticles, and the dressings were performed every 48 hours. The project was approved by the Animal Experiments Committee. Hydrogel dressings are transparent and allow accurate visualization of the center of the lesion. The part of the dressing in contact with the wound kept the medium moist, promoting interaction with the fluid of the lesion, besides adsorbing the moisture produced. The dressing replacement didn’t cause discomfort or pain, since the animals were manually contained during the procedure, and the cover is easy to remove without causing trauma to the healing tissue. Wounds remained free of fibrin formation and necrosis, and serous exudation of lesions was scarce. At 21 days all the lesions were healed showing that dressings weren’t negative to the second intention healing process.
Toxicity study using rat (WISTAR) model of a hydrogel dressing with silver nanoparticles crosslinked and sterilized by gamma radiation
2019 - SOUSA, GRAZIELLY M. de; GEMELLI, KARINE K.; MARTINS, OZENILDE A.R.; OLIVEIRA, MARIA J.A. de; ALCANTARA, MARA T.S.; LUGAO, ADEMAR B.; ROGERO, JOSE R.
Silver nanoparticles (NPAg) have a bactericidal and bacteriostatic action in combination with hydrogels to recover the damaged tissue, promoting healing of the wound. The objective of this study was to evaluate the toxicity of the hydrogel dressing with NPAg from the analysis of possible toxic effects on renal and hepatic functions. It is an experimental study with 85 male Wistar rats, young adults. Nanoprate hydrogel and bidrogel dressings were used at concentrations of 22 and 44 ppm, both crosslinked and sterilized by irradiation with gamma rays at the 25 kGy dose at the center of radiation technology (CTR). The animals were distributed according to the treatment received after surgical induction of the wound on the animal's back. They were euthanized with 24 hours, 3, 7, 14, 21 and 30 days and after collecting the blood to determine the biochemical parameters. The project was approved by CEUA FAPAC ITPAC PORTO. Data were analyzed using the Past, Shapiro-Wilk and Kruskal-Wallis programs. For distribution and comparison data ANOVA and Tukey test with a significance level of 95%. No changes were observed in relation to biochemical parameters (TGP, TGO, urea and creatinine), and there were no statistically significant differences between the three groups of animals, independent of time. It was possible to observe that the animals treated with 44 ppm had always lower mean values than the other two groups in all analyzes. The study showed that the dressings of NPAg tested may not induce toxicity, being necessary to complement with other tests, such as histopathological study and atomic absorption spectroscopy.
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.
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.
Synthesis and characterization of polymeric hydrogel containing caffeine for cosmeceutical applications
2017 - SANTOS, TIAGO C.; OLIVEIRA, MARIA J.A.; LUGAO, ADEMAR B.
Caffeine, a substance with belongs to the group of methylxanthines, is alkaloids that penetrate in the human epidermis but is not easily absorbed into the bloodstream. With a dermatological active substance, it exerts action on the subcutaneous adipose tissue causing adipocyte lipolysis through the inhibition of phosphodiesterase. Based on these considerations, the objective of this study was to investigate the behavior of caffeine in a polymeric hydrogel matrix, for possible cosmeceutical applications. The hydrogels were cross-linked and sterilized by colbat-60 source gamma irradiation. In the characterization, were used thermogravimetry (TGA), scanning electron microscopy (SEM), differential scanning calorimetry (DSC). It was possible to observe by SEM the presence of crystals in the hydrogel sample. The DSC experiment confirmed a crystallinity of the sample and that caffeine is not degraded by gamma irradiation at 25 kGy. The results were satisfactory, allowing a new investigations that certify the benefits of its application.
Síntese de nanoparticulas de ouro estabilizadas por quitosana
2015 - GERALDES, ADRIANA N.; OLIVEIRA, MARIA J.A.; SILVA, ANDRESSA A. da; LEAL, JESSICA; BATISTA, JORGE G.S.; LUGAO, ADEMAR B.
Drug delivery glucantime in PVP/chitosan membranes
2015 - OLIVEIRA, MARIA J.A.; AMATO, VALDIR S.; LUGAO, ADEMAR B.; PARRA, DUCLERC F.