Mucoadhesive chitosan-coated PLGA nanoparticles for oral delivery of ferulic acid

This paper describes the development and in vitro evaluation of poly(lactic-co-glycolic acid) (PLGA) nanoparticles coated with chitosan (CS) for oral delivery of ferulic acid (FA). Nanoparticles were obtained by an emulsion evaporation technique and characterized. Furthermore, we evaluated the scavenging activity over hypochlorous acid (HOCl), the cytotoxicity over tumour cells and the in vitro intestinal permeability. Nanoparticles were spherical with a mean diameter of 242 nm, positive zeta potential and 50% of encapsulation efficiency. The in vitro release in phosphate buffered saline (PBS) (pH 7.4) demonstrated a prolonged and biphasic profile diffusion-controlled. In simulated gastrointestinal fluids, about 15% of FA was released in gastric fluid and a negligible release was observed in the intestinal fluid. In the HOCl scavenging activity and cytotoxicity over B16-F10 and HeLa cells, FA-loaded nanoparticles presented the same efficacy of the free drug. Besides, in the antioxidant and cytotoxic assay, CS contributed to FA effects. In the intestinal permeability study, FA-loaded nanoparticles exhibited a permeation of 6% through the Caco-2 monolayer and 20% through the Caco-2/HT29-MTX/Raji B co-culture. CS-coated PLGA nanoparticles are promising carriers for oral delivery of FA.This study was supported by the CAPES (Coordenação de Aperfeiçoamento de Pessoal de Ńıvel Superior) in the form of doctoral fellowship for I.A. de Lima, Fundação Araucária (17/17) CNPq (Conselho Nacional de Desenvolvimento Científico e tecnológico) and Finep (Financiadora de Estudos and Projetos) for partial financial support

Mucoadhesive chitosan-coated PLGA nanoparticles for oral delivery of ferulic acid

This paper describes the development and in vitro evaluation of poly(lactic-co-glycolic acid) (PLGA) nanoparticles coated with chitosan (CS) for oral delivery of ferulic acid (FA). Nanoparticles were obtained by an emulsion evaporation technique and characterized. Furthermore, we evaluated the scavenging activity over hypochlorous acid (HOCl), the cytotoxicity over tumour cells and the in vitro intestinal permeability. Nanoparticles were spherical with a mean diameter of 242 nm, positive zeta potential and 50% of encapsulation efficiency. The in vitro release in phosphate buffered saline (PBS) (pH 7.4) demonstrated a prolonged and biphasic profile diffusion-controlled. In simulated gastrointestinal fluids, about 15% of FA was released in gastric fluid and a negligible release was observed in the intestinal fluid. In the HOCl scavenging activity and cytotoxicity over B16-F10 and HeLa cells, FA-loaded nanoparticles presented the same efficacy of the free drug. Besides, in the antioxidant and cytotoxic assay, CS contributed to FA effects. In the intestinal permeability study, FA-loaded nanoparticles exhibited a permeation of 6% through the Caco-2 monolayer and 20% through the Caco-2/HT29-MTX/Raji B co-culture. CS-coated PLGA nanoparticles are promising carriers for oral delivery of FA.This study was supported by the CAPES (Coordenação de Aperfeiçoamento de Pessoal de Ńıvel Superior) in the form of doctoral fellowship for I.A. de Lima, Fundação Araucária (17/17) CNPq (Conselho Nacional de Desenvolvimento Científico e tecnológico) and Finep (Financiadora de Estudos and Projetos) for partial financial support

Epistemic insights: Contemplating tensions between policy influences and creativity in school science

Creativity and the way it could be supported in schools is understood differently by policy makers, practitioners and scientists. This article reviews, with a chronological lens, the development of policies that include teaching creativity and teaching for creativity. The epistemic tensions between the intentions of government and the nature of creativity as it emerges in learning or scientific work is introduced and reflected upon. There have been more than nine key educational policies that have been introduced over the last 50 years. Each of these are considered in this article and related to the ways that creativity is understood and expected to be taught, supported or enacted in schools by policy makers. In light of the need to support creativity as a key twenty‐first‐century skill, to ultimately enable current students (who will become the next generation of scientists) to develop the capabilities to address global concerns, this article highlights issues related to this issue. Epistemic insights are offered that relate to the development of aspects of creativity, including questioning, developing alternate ideas, ‘seeing’ things differently, innovation, curiosity, problem solving and evaluating. The ways that policy related to creativity in science appears not to recognise how creativity can be reified in these ways in schools suggests the need for rapid review, especially in light of the upcoming international creativity tests in 2021

Identifying patterns of alumni commitment in key strategic relationship programmes

Higher education institutions (HEIs) need to understand their alumni when drawing strategic relationship programmes. This paper aims to identify clusters of alumni based on their commitment relationship and to analyse factors influencing their intention to collaborate with the HEI. The study took place at a Portuguese university, considering a dataset of 1075 of alumni asserting intention to collaborate. First, a cluster analysis was conducted to identify patterns of commitment relationship. Secondly, a logistic regression was run to identify determinants of intention to collaborate. Both techniques revealed the decisive role of HEI commitment in the process. Relationship advantages and positive feelings towards the HEI were also pointed out as important. Alumni asserted recommendations, further training, sharing experiences and giving help as ways to collaborate with HEI. Regression results suggest that sociodemographic variables such as gender, marital status and volunteering are significantly associated with a probability to collaborate. Results also show that affiliation in sororities/fraternities and participation in extracurricular activities are significantly associated with that collaborative intention. The findings provide clues to support strategic relationship programmes based on consistent marketing campaigns, while bringing value to the literature in the European context, where alumni culture requires real insights to evolve.info:eu-repo/semantics/publishedVersio

Pharmacokinetic characteristics and anticancer effects of 5-Fluorouracil loaded nanoparticles

<p>Abstract</p> <p>Background</p> <p>It is expected that prolonged circulation of anticancer drugs will increase their anticancer activity while decreasing their toxic side effects. The purpose of this study was to prepare 5-fluorouracil (5-FU) loaded block copolymers, with poly(γ-benzyl-L-glutamate) (PBLG) as the hydrophobic block and poly(ethylene glycol) (PEG) as the hydrophilic block, and then examine the 5-FU release characteristics, pharmacokinetics, and anticancer effects of this novel compound.</p> <p>Methods</p> <p>5-FU loaded PEG-PBLG (5-FU/PEG-PBLG) nanoparticles were prepared by dialysis and then scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to observe the shape and size of the nanoparticles, and ultraviolet spectrophotometry was used to evaluate the 5-FU in vitro release characteristics. The pharmacokinetic parameters of 5-FU/PEG-PBLG nanoparticles in rabbit plasma were determined by measuring the 5-FUby high-performance liquid chromatography (HPLC). To study in vivo effects, LoVo cells (human colon cancer cell line) or Tca8113 cells (human oral squamous cell carcinoma cell line) were implanted in BALB/c nude mice that were subsequently treated with 5-FU or 5-FU/PEG-PBLG nanospheres.</p> <p>Results</p> <p>5-FU/PEG-PBLG nanoparticles had a core-shell spherical structure with a diameter of 200 nm and a shell thickness of 30 nm. The drug loading capacity was 27.1% and the drug encapsulation was 61.5%. Compared with 5-FU, 5-FU/PEG-PBLG nanoparticles had a longer elimination half-life (t_1/2, 33.3 h vs. 5 min), lower peak concentration (C, 4563.5 μg/L vs. 17047.3 μg/L), and greater distribution volume (V_D, 0.114 L vs. 0.069 L). Compared with a blank control, LoVo cell xenografts and Tca8113 cell xenografts treated with 5-FU or 5-FU/PEG-PBLG nanoparticles grew slower and had prolonged tumor doubling times. 5-FU/PEG-PBLG nanoparticles showed greater inhibition of tumor growth than 5-FU (p < 0.01). In the PEG-PBLG nanoparticle control group, there was no tumor inhibition (p > 0.05).</p> <p>Conclusion</p> <p>In our model system, 5-FU/PEG-PBLG nanoparticles changed the pharmacokinetic behavior of 5-FU, thus increasing its anticancer activity. 5-Fluorouracil loaded nanoparticles have potential as a novel anticancer drug that may have useful clinical applications.</p

Biomaterials Approaches to Combating Oral Biofilms and Dental Disease

Background: Possibilities for biomaterials to impact the dental caries epidemic are reviewed with emphasis placed on novel delivery biomaterials and new therapeutic targets

Sources of stakeholder salience in the responsible investment movement: why do investors sign the Principles for Responsible Investment?

Since its inception in 2006, the United Nations-backed Principles for Responsible Investment (PRI) have grown to over 1300 signatories representing over $45 trillion. This growth is not slowing down. In this paper, we argue that there is a set of attributes which make the PRI salient as a stakeholder and its claim to sign the six PRI important to institutional investors. We use Mitchell et al.’s (Acad Manag Rev 22:853–886, 1997) theoretical framework of stakeholder salience, as extended by Gifford (J Bus Eth 92:79–97, 2010). We use as evidence confidential data from the annual survey of signatories carried out by the PRI in a 5-year period between 2007 and 2011. The findings highlight pragmatic and organizational legitimacy, normative and utilitarian power, and management values as the attributes that contribute most to the salience of the PRI as a stakeholder