49 research outputs found
Ocorrência de Salmonella sp. em surtos de doenças transmitidas por alimentos no Rio Grande do Sul em 2000
No Rio Grande do Sul, desde 1993 a salmonelose tem sido a Doença Transmitida por Alimentos (DTA) de maior ocorrência, assim como em outros estados brasileiros e países da Europa e Américas. Mudanças nos sistemas de produção de alimentos e pressão social têm levado ao aumento da incidência de DTA. O presente trabalho teve por objetivo analisar a ocorrência de surtos de salmonelose Transmitidas por Alimentos ocorridos no Rio Grande do Sul no ano de 2000, destacando os principais alimentos envolvidos e os fatores implicados nestes surtos. Foram analisados 99 relatórios finais de investigação de surtos. A salmonelose correspondeu a 74,7% dos surtos confirmados, sendo 72,2% dos surtos associados ao consumo de alimentos preparados com ovos. A utilização de matéria-prima sem inspeção sanitária e a manipulação incorreta dos alimentos constituíram-se nos fatores predisponentes à contaminação dos alimentos por Salmonella, em 73% dos surtos investigados. Os alimentos envolvidos nos surtos de DTAs foram preparados (48,6%) e consumidos (55,4%), em sua maioria, em residências. Os resultados do presente estudo sugerem a necessidade de controle da Salmonella nas aves, a partir da granja, e da adoção de boas práticas de fabricação
Enhanced dissolution efficiency of tamoxifen combined with methacrylate copolymers in amorphous solid dispersions
Amorphous solid dispersions (SDs) containing poorly soluble tamoxifen dispersed in a meth(acrylate) copolymer combination were proposed as a controlled release system. The objective of this work was to investigate the characteristics and performance of the tamoxifen–polymer mixture and evaluate the changes in functionality through a supersaturating dissolution study condition while comparing it to a physical mixture at a fixed drug-loading proportion. Two polymers, Eudragit® L 100 and Eudragit® RL 100, were used to prepare SDs with a 1:1 polymer ratio, containing 10%, 20%, or 30% (wt/wt%) of tamoxifen, by the solvent evaporation method. A physical mixture containing 30% of tamoxifen was also prepared for comparison. SDs were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. Dissolution tests were conducted under non-sink conditions to verify the occurrence of drug recrystallization upon its release. Solid-state characterizations confirmed that the drug was in the amorphous state within the polymeric matrix. Tamoxifen release in an acidic medium was mainly affected by the increase in drug concentration caused by the possible loss of interactions that characterize the main polymer functionalities. At pH 7.4, supersaturation was slowly achieved while also contributing to the increase in the kinetic solubility of the drug. The physical mixture demonstrated the best overall performance, suggesting that the polymeric interactions may have negatively affected the drug release. The combination of polymers in the composing SD proved to be a promising strategy to tailor the delivery of poorly soluble drugs. Our study highlights important information on the behavior of tamoxifen as a poorly soluble drug in supersaturating dissolution conditions while released from SD systems.This work was funded by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
(CAPES/Brazil), by the Portuguese Science and Technology Foundation (FCT/MCT), and European Funds
(PRODER/COMPETE) under the projects M-ERA-NET/0004/2015 and UIDB/04469/2020 (strategic fund) and
co-financed by FEDER under the Partnership Agreement PT2020.info:eu-repo/semantics/publishedVersio
pH-responsive phthalate cashew gum nanoparticles for improving drugs delivery and anti-Trypanosoma cruzi efficacy
Funding Information: The authors acknowledge Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco ( FACEPE ) for a scholarship. This study was supported by funding from the Spanish Group CTS-946 and project P18-RT-3786 . Publisher Copyright: © 2023 Elsevier B.V.Nanotechnology is a crucial technology in recent years has resulted in new and creative applications of nanomedicine. Polymeric nanoparticles have increasing demands in pharmaceutical applications and require high reproducibility, homogeneity, and control over their properties. Work explores the use of cashew phthalate gum (PCG) as a particle-forming polymer. PCG exhibited a pH-sensitive behavior due to the of acid groups on its chains, and control drug release. We report the development of nanoparticles carrying benznidazole. Formulations were characterized by DLS, encapsulation efficiency, drug loading, FTIR, pH-responsive behavior, release, and in vitro kinetics. Interaction between polymer and drug was an evaluated by molecular dynamics. Morphology was observed by SEM, and in vitro cytotoxicity by MTT assay. Trypanocidal effect for epimastigote and trypomastigote forms was also evaluated. NPs responded to the slightly basic pH, triggering the release of BNZ. In acidic medium, they presented small size, spherical shape, and good stability. It was indicated NP with enhanced biological activity, reduced cytotoxicity, high anti T. cruzi performance, and pH-sensitive release. This work investigated properties related to the development and enhancement of nanoparticles. PCG has specific physicochemical properties that make it a promising alternative to drug delivery, however, there are still challenges to be overcome.publishersversionpublishe
pH-responsive phthalate cashew gum nanoparticles for improving drugs delivery and anti-Trypanosoma cruzi efficacy
Nanotechnology is a crucial technology in recent years has resulted in new and creative applications of nanomedicine. Polymeric nanoparticles have increasing demands in pharmaceutical applications and require high reproducibility, homogeneity, and control over their properties. Work explores the use of cashew phthalate gum (PCG) as a particle-forming polymer. PCG exhibited a pH-sensitive behavior due to the of acid groups on its chains, and control drug release. We report the development of nanoparticles carrying benznidazole. Formulations were characterized by DLS, encapsulation efficiency, drug loading, FTIR, pH-responsive behavior, release, and in vitro kinetics. Interaction between polymer and drug was an evaluated by molecular dynamics. Morphology was observed by SEM, and in vitro cytotoxicity by MTT assay. Trypanocidal effect for epimastigote and trypomastigote forms was also evaluated. NPs responded to the slightly basic pH, triggering the release of BNZ. In acidic medium, they presented small size, spherical shape, and good stability. It was indicated NP with enhanced biological activity, reduced cytotoxicity, high anti T. cruzi performance, and pH-sensitive release. This work investigated properties related to the development and enhancement of nanoparticles. PCG has specific physicochemical properties that make it a promising alternative to drug delivery, however, there are still challenges to be overcome.The authors acknowledge Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco (FACEPE) for a scholarship. This study was supported by funding from the Spanish Group CTS-946 and project P18-RT-3786
Study of the effect of solvent on acetylate cashew gum-based nanoparticles properties and antimicrobial activity
The aim of this work was to investigate the influence of acetone and dimethyl sulfoxide (DMSO) on acetylated cashew gun (ACG) nanoparticles parameters and to assess their antimicrobial activity. C1 nanoparticles presented smaller size (81.3 nm) than compared to C2 (115.7 nm). Although, acetone formed particles with lower PDI value. Both C1 and C2 presented negative zeta potential (-39.8 and -31.7 respectively). Particle tracking analysis showed that C1 was slightly more concentrated than C2. No statistical differences (p 0.05) between the same samples after 5 months were found. Both samples did not exert inhibitory effect on E. coli, on the contrary S. aureus, in which both C1 (36.9%) and C2 (19.9%) provided important inhibitory effect. C1 presented a more pronounced antifungal effect (81.2%), compared to C2 (18.8%), indicating a promising platform to be used in several biomedical application. Keywords: polysaccharide, nanoparticles, biopolymers, modification, biological applications of polymers.