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1.
Int J Biol Macromol ; 212: 579-593, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35618092

RESUMO

The parameters used in the preparation of polymeric nanoparticles can influence its ability to photooxidate biomolecules. This work evaluated the effects of four parameter to prepare Poly(3-hydroxybutyrate) (PHB) nanoparticle loaded with aluminum and indium phthalocyanine (AlPc and InPc), together with iron oxide nanoparticles, assessing their influence on the size, the entrapment efficiency, and the nanoparticles recovery efficacy. The capability of free, and encapsulated, AlPc and InPc in photooxidating the bovine serum albumin (BSA) and tryptophan (Trp) was monitored by fluorescence. The AlPc-loaded nanoparticles had a larger size and a greater entrapment efficiency than that obtained by InPc-loaded nanoparticles. The free InPc was more efficient than the free AlPc to photooxidize the BSA and Trp; whereas the encapsulated AlPc was more efficient than encapsulated InPc to photooxidize the biomolecules. The higher hydrophobicity of the AlPc, combined with the greater aggregation state and the major interaction with the BSA, quenching the capacity of the free AlPc to photooxidate the biomolecules; whereas the greater interaction of the AlPc with PHB reduce the aggregation effect on the free molecules in the aqueous phase and increase the entrapment efficiency, resulting in an improving of the photodynamic efficiency and an increase of the photooxidation rate constant.


Assuntos
Nanopartículas de Magnetita , Nanopartículas , Índio , Fármacos Fotossensibilizantes/farmacologia , Polímeros , Soroalbumina Bovina
2.
J Photochem Photobiol B ; 198: 111582, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31442827

RESUMO

Poly(lactide-co-glycolide) (PLGA) has been used for the encapsulation of phthalocyanine motived by its biocompatibility and biodegradability. Many studies have already been done to evaluate the influence of parameters used in the PLGA nanoparticle synthesis but without the evaluation of the combinatory interaction between these parameters on the nanoparticulate properties. Ga(III)-phthalocyanine (GaPc) was encapsulated into the PEGlated PLGA-nanoparticles and the individual and combinatory effects of the emulsification time, the method used for the nanoparticle synthesis and the temperature of the aqueous phase was evaluated on the size, entrapment efficiency, efficacy of nanoparticle recovery, residual PVA and zeta potential value using a 23 factorial design (FD). Mathematical models were adjustable to the data and evolutionary operations were performed to optimize the nanoparticle size. The ability of the optimized nanoparticle to decrease the viability of the Hepa-1C1C7 cell and the blood red cell was also evaluated. The FD disclosed the emulsification-diffusion method decreased the residual PVA and the size of PLGA-PEG nanoparticle, but also decreased the entrapment efficiency of GaPc, the zeta potential absolute value and the recovery efficacy of nanoparticles. The combinatory effect between the method used in the nanoparticle preparation and the temperature of aqueous phase influenced four of the five evaluated properties. The viability of Hepa-1C1C7 cells was reduced until 13× when the cells were irradiated in the presence of encapsulated GaPc while it was decreased until 4.7× when the experiment was carried out with the free GaPc. The encapsulated GaPc was also more efficient to cause the haemolysis of the RBC than it was the free GaPc. The optimization of the nanoparticles synthesis increased the efficiency of the GaPc to oxidize the evaluated cells.


Assuntos
Gálio/química , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Indóis/química , Isoindóis , Nanopartículas/toxicidade , Tamanho da Partícula , Temperatura
3.
ScientificWorldJournal ; 2014: 917348, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24578668

RESUMO

The use of vermicompost (humified material) for treating wastewaters, remediating polluted soils, improving agricultural productivity, protecting crop production, and developing sensitive analytical methods is reviewed here, covering the past 17 years. The main advantages of vermicompost, considering all applications covered in this paper, comprise (i) easy acquisition, (ii) low costs, (iii) structural, chemical, and biological characteristics responsible for exceptional adsorptive capacities as well as pollutant degradation, and (iv) the promotion of biocontrol. Specifically, for wastewater decontamination, a considerable number of works have verified the adsorption of toxic metals, but the application of vermicompost is still scarce for the retention of organic compounds. Problems related to the final disposal of enriched vermicompost (after treatment steps) are often found, in spite of some successful destinations such as organic fertilizer. For decontaminating soils, the use of vermicompost is quite scarce, mainly for inorganic pollutants. In agricultural productivity and biocontrol, vermicompost imparts remarkable benefits regarding soil aggregation, plant nutrition, and the development of beneficial microorganisms against phytopathogens. Finally, the use of vermicompost in sensitive analytical methods for quantifying toxic metals is the newest application of this adsorbent.


Assuntos
Técnicas de Química Analítica/métodos , Fertilizantes , Substâncias Húmicas/análise , Substâncias Húmicas/estatística & dados numéricos , Águas Residuárias/química , Purificação da Água/métodos , Adsorção , Silicatos de Alumínio , Animais , Agentes de Controle Biológico , Argila , Substâncias Húmicas/normas , Microscopia Eletrônica , Estrutura Molecular , Oligoquetos/fisiologia , Porosidade , Solo/química
4.
Electron. j. biotechnol ; 14(6): 7-7, Nov. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640524

RESUMO

The frequent contamination of water resources with drugs comprises one the most important environmental problems. In order to avoid serious disturbances for aquatic life, efficient and economically viable procedures should be developed for removing common pollutants, as paracetamol. From these considerations, the present work evaluated the efficiency of sugar cane bagasse (SCB) and vegetable sponge (VS), two natural adsorbents commonly found in Brazil, for retaining paracetamol molecules dispersed in aqueous solutions. Thus, systems composed of glass columns and peristaltic pumps were optimized and, for pH, the best value was 7.0. After optimisation, adsorption isotherms were built and it was possible to calculate the MAC F values for SCB (120.5 ug/g) and VS (37.5 ug/g). Additionally, real matrices of pretreated water, from a municipal plant for water catchment, were enriched with paracetamol at 5 uM and passed through glass columns packed with SCB, VS and activated carbon (AC). The results showed that SCB was more attractive than AC in terms of price and efficiency (60 percent against 45 percent adsorption, respectively), while VS was responsible for removing 40 percent of paracetamol dissolved in the enriched water samples. Thus, the proposed natural adsorbents can be classified as viable materials to remove paracetamol from water used for human consumption.


Assuntos
Acetaminofen/química , Celulose/química , Luffa/química , Purificação da Água/métodos , Adsorção , Temperatura , Poluentes Químicos da Água
5.
Braz. arch. biol. technol ; 53(4): 931-938, July-Aug. 2010. graf, ilus
Artigo em Inglês | LILACS | ID: lil-554788

RESUMO

A methodology involving sugar cane bagasse bioadsorbent was developed in order to remove the carcinogenic congo red dye from aqueous medium. The results showed high efficiency with retention of 64 ± 6 percent in synthetic congo red solution and 94 ± 5 percent in effluent enriched with congo red, at 10.0 g of the bioadsorbent. The adsorption system provided a maximum adsorption capacity of 4.43 mg/g. Tests showed independence adsorption properties, when compared with the column flow rates. The treatment units could be operated with flexibility. From the results, it was possible to conclude that sugar cane bagasse could be an adequate bioadsorbent.


Neste trabalho foi desenvolvida uma metodologia de remoção do corante carcinogênico congo red de sistemas aquosos. Os resultados mostraram uma elevada eficiência de remoção sendo de 64 ± 6 por cento para soluções sintéticas de vermelho congo, e 94 ± 5 por cento para efluente industrial enriquecido com vermelho congo utilizando 10 g de bioadsorvente. A capacidade máxima adsotiva encontrada foi de 4,43 mg/g. Os testes de percolação revelaram independência das porcentagens adsortivas em relação às vazões das colunas. Estes resultados indicam viabilidade de uso do bagaço de cana-de-açucar no tratamento de efluentes contendo o congo red.

6.
ACM arq. catarin. med ; 38(3)jul.-set. 2009. ilus, graf
Artigo em Português | LILACS | ID: lil-663078

RESUMO

O presente trabalho contempla a avaliação dacapacidade fotossensibilizante de alguns derivadosporfirínicos para futuro emprego em fotoquimioterapia.As substâncias testadas foram: protoporfirina IX (PpIX),protoporfirina IX de magnésio (MgPpIX), protoporfirinaIX de zinco (ZnPpIX), octaetilporfirina (OEP) eoctaetilporfirina de vanadil (VOOEP). Os testesconsistiram na avaliação e comparação da capacidadedestas substâncias em oxidar biomoléculas e destruircélulas na presença de luz e oxigênio. Os resultadosrevelaram que as diferenças observadas na eficiênciadestas porfirinas podem estar associadas com asdiferenças nas estruturas das mesmas. Foi verificadoque PpIX, MgPpIX e ZnPpIX são mais eficientes queOEP e VOOEP na fotoxidação de biomoléculas efotodestruição de células. Os dados obtidos indicam apossibilidade de um futuro emprego destas porfirinas emfotoquimioterapia.


The work includes the assessment of photosensitizingcapacity of some porphyrinic derivates for futureapplication in PDT. We evaluated the photosensitizingpotential of octaethylporphyrin (OEP), vanadyloctaethylporphyrin (VOOEP), protoporphyrin IX (PpIX),zinc protoporphyrin IX (ZnPpIX) and magnesiumprotoporphyrin IX (MgPpIX) for use inphotochemotherapy. This study was performed throughthe percentage of biomolecules photoxidation (tryptophan- Trp and bovine serum albumin ? BSA) and cellsphotohemolysis provoked by OEP, VOOEP, PpIX,ZnPpIX and MgPpIX. The results demonstrated thatPpIX, ZnPpIX and MgPpIX are more efficient than OEPand VOOEP in the oxidadion of biomolecules andhemolysis of cells in the presence of light and oxygen.The differences observed in the photodynamic activitybetween porphyrins could be associated with differencesin their molecular structures. These results stimulate newstudies with the objective to transform these drugs intonew options for use in photochemotherapy.

7.
Rev. bras. anal. clin ; 38(1): 23-27, 2006. tab
Artigo em Português | LILACS | ID: lil-485875

RESUMO

Diversos trabalhos têm atribuído aos flavonóides inúmeras propriedades farmacológicas. Dentre esses flavonóides a antocianina (extraída da uva roxa) e a naringenina (extraída da laranja) demonstraram redução dos níveis sangüíneos de glicose e triacilglicerolem coelhos diabéticos. Apesar de, segundo relatos na literatura, a toxicidade em relação flavonóides parecer rara, são citadas reações adversas, quando usadasdoses farmacológicas crônicas, como hepatite e perda de peso de alguns órgãos como o fígado. O presente ensaio teve como objetivo investigar se as substâncias testadas nessas doses terapêuticas ocasionavam algum efeito adverso no metabolismo hepático de coelhos normais.O experimento teve 30 dias de duração, sendo as medidas de peso e dosagens dos constituintes do sangue proteínas totais, alanina aminotransferase, aspartato aminotransferase, gama – glutamiltranspeptidase) realizadas a 0, 15 e 30 dias. Os resultados indicaram que, de modo geral, as substâncias – teste nãoocasionaram alterações relevantes no metabolismo desses animais saudáveis.


Assuntos
Animais , Coelhos , Antocianinas , Análise Química do Sangue , Doença Hepática Induzida por Substâncias e Drogas , Resistência a Medicamentos , Fígado/lesões , Hepatopatias , Coelhos
8.
J. bras. patol. med. lab ; 40(6): 383-390, dez. 2004. ilus
Artigo em Inglês | LILACS | ID: lil-393277

RESUMO

A terapia fotodinâmica (TFD) é um promissor tratamento clínico que emprega a combinação de luz visível, oxigênio e uma substância fotossensibilizadora para tratar doenças de caráter oncológico. Esse tipo de tratamento induz a morte celular programada (apoptose) em tecido tumoral. No entanto, o mecanismo de indução de apoptose por TFD não está bem caracterizado. Muitos fotossensibilizadores possuem como alvo principal a mitocôndria. O tratamento com TFD causa danos nessa organela e induz a apoptose através da liberação de citocromo c, fator de indução de apoptose, Smac/DIABLO e certas pró-caspases. A liberação dessas proteínas, a partir da mitocôndria, é regulada por uma família de proteínas pró e antiapoptóticas, conhecida como família BCL-2. A proposta dessa minirrevisão é apresentar algumas publicações recentes que focalizam o envolvimento da mitocôndria em apoptose de células cancerígenas induzida por TFD.


Assuntos
Humanos , Apoptose , Fotoquimioterapia/métodos , Neoplasias/patologia , Neoplasias/tratamento farmacológico
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