Prevention and treatment of diabetic retinopathy by natural antioxidant containing in chitosan-based nanomedicines

Oxidative processes are critical factors in ocular conditions that may lead to pathologies such as Diabetic Retinopahty due to structural and functional modification of the tissues, apoptosis of capillary cells and retinal microvascular changes, making the loss of vision inevitable. Application of antioxidants may reduce apoptosis and restores partially functional tissues. Considering the multiple benefits of antioxidants in DR and that conjunctival drug permeability improvement is one of the major challenges in ocular drug delivery, the major topic of this work is to study the absorption capacity and consequent bioavailability of natural antioxidants incorporated in chitosan-based nanoparticles to prevent and treat DR. In this regards, it is proposed to characterize, quantify and compare the antioxidant potential of Salvia sp. and Satureja montana extracts and their main pure antioxidants: rutin, caffeic and clorogenic acid. Then, antioxidant compounds are encapsulated into different chitosan-based nanoparticles, nanoparticles and release profile characterized and ocular permeation evaluated using in vitro cell models. Finally, the effect of antioxidant nanomedicines across human ocular is evaluated in diabetic animal after topical administration in vivo.info:eu-repo/semantics/publishedVersio

Antagonizing the spindle assembly checkpoint silencing enhances paclitaxel and Navitoclax-mediated apoptosis with distinct mechanistic

Antimitotic drugs arrest cells in mitosis through chronic activation of the spindle assembly checkpoint (SAC), leading to cell death. However, drug-treated cancer cells can escape death by undergoing mitotic slippage, due to premature mitotic exit. Therefore, overcoming slippage issue is a promising chemotherapeutic strategy to improve the effectiveness of antimitotics. Here, we antagonized SAC silencing by knocking down the MAD2-binding protein p31comet, to delay mitotic slippage, and tracked cancer cells treated with the antimitotic drug paclitaxel, over 3 days live-cell time-lapse analysis. We found that in the absence of p31comet, the duration of mitotic block was increased in cells challenged with nanomolar concentrations of paclitaxel, leading to an additive effects in terms of cell death which was predominantly anticipated during the first mitosis. As accumulation of an apoptotic signal was suggested to prevent mitotic slippage, when we challenged p31comet-depleted mitotic-arrested cells with the apoptosis potentiator Navitoclax (previously called ABT-263), cell fate was shifted to accelerated post-mitotic death. We conclude that inhibition of SAC silencing is critical for enhancing the lethality of antimitotic drugs as well as that of therapeutic apoptosis-inducing small molecules, with distinct mechanisms. The study highlights the potential of p31comet as a target for antimitotic therapies.The authors gratefully acknowledge CESPU—Cooperativa de Ensino Superior Politécnico e Universitário, which financed this work under the projects “ComeTarget_CESPU_2017” and “ComeTax”. Ana C. Henriques acknowledge FCT-Fundação para a Ciência e a Tecnologia for financial support (Grant SFRH/BD/116167/2016)

The roles of vitamin d and cathelicidin in type 1 diabetes susceptibility

Type 1 diabetes has an increasingly greater incidence and prevalence with no cure available. Vitamin D supplementation is well documented to reduce the risk of developing type 1 diabetes. Being involved in the modulation of cathelicidin expression, the question whether cathelicidin may be one of the underlying cause arises. Cathelicidin has been implicated in both the development and the protection against type 1 diabetes by mediating the interplay between the gut microbiome, the immune system and ß cell function. While its potential on type 1 diabetes treatment seems high, the understanding of its effects is still limited. This review aims to contribute to a more comprehensive understanding of the potential of vitamin D and cathelicidin as adjuvants in type 1 diabetes therapy.This work was financed by FEDER – Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 – Operacional Programme for Competitiveness and Internationalization (POCI), Portugal 2020, and by Portuguese funds through FCT – Fundação para a Ciência e a Tecnologia/ Ministério da Ciência, Tecnologia e Ensino Superior in the framework of the project PTDC/MED-OUT/30466/2017 and ‘Institute for Research and Innovation in Health Sciences’ (FCT – UID/BIM/04293/2019). Cecília Cristelo and Alexandra Machado would like to thank to Fundação para a Ciência e a Tecnologia (FCT), Portugal for financial support (SFRH/BD/139402/2018 and SFRH/BD132000/2017, respectively)

Selection of low swelling materials for protein adsorption from white wines

The protein adsorption capacity of different materials was evaluated to assess their potential efficacy as alternative adsorbents for the removal of proteins from wines, with the purpose of finding suitable low-swelling materials that could be used in a percolated bed. The adsorbents tested were thermally treated sodium bentonite, low-swelling adsorbing clays, ion exchange resins and other protein adsorbents (silica gel, hydroxyapatite and alumina). The materials were evaluated by analysing both the capacity to stabilize untreated white wines, according to a heat test, and by characterizing the adsorption isotherms of bovine serum albumin (BSA) in a model wine (water, ethanol and K-bitartrate). Breakthrough curves in a packed bed were determined experimentally for some materials, showing the influence of the adsorption isotherm shape. Some ionexchange resins showed a favourable behaviour and have good potential as alternative adsorbents

The voices and actions of child activists against the climate crisis

Aim. The work has as main objective to present some of the actions of children considered activists to face the climate crisis through social media. Technologies and social media allow them a new form of existence and action through their posts, whether is in video, photo or text format, promoting interactions and discussions that captivate hundreds or thousands of followers. Methods. Data collection was carried out from a digital ethnography, analysing the social media and linked news in the media of 13 children from different countries (Australia, United States, India, Holland, England, Indonesia, South Africa, Uganda and Sweden) over an 18-month period. Results. To understand the data, digital ethnography was used as a strategy to follow the main interactions and online mobilisations through different social media (Facebook, Instagram and Twitter), as well as linked news in the media about those children, and articulation of them with governmental, non-governmental organizations and private companies. In relation to the selection of participants, the pro le of a child activist was added and through the algorithms of these platforms other activists with similar pro les were found that promote content about climate justice. Conclusions. It was possible to identify that the Internet has enabled the visibility and articulation of children’s actions on the theme, and how this engagement has promoted awareness and changes to ght against the climate crisis. It is worth emphasising the importance of digital literacy so that access to these spaces is carried out safely and responsibly for this social group.This work was financially supported by Portuguese national funds through the FCT (Foundation for Science and Technology) within the framework of the CIEC (Research Center for Child Studies of the University of Minho) projects under the references UIDB/00317/2020 and UIDP/00317/2020

Caracterização e avaliação da pastagem do rebanho de agricultores familiares do nordeste paraense.

No Nordeste Paraense alguns agricultores familiares têm implantado pequenas áreas de pastagens e manejado pequenos rebanhos com o objetivo de aplicar eventuais ganhos obtidos com os cultivos, criando uma poupança a ser utilizada nas necessidades futuras da família ou da propriedade. Há indícios de problemas nas pastagens e no rebanho que limitam tanto a produção e a sustentabilidade da pecuária, como comprometem os cultivos agrícolas que realmente sustentam a propriedade. Este estudo tratou de identificar as principais limitações e propor alternativas de manejo que sejam econômica e ecologicamente mais sustentáveis. Na primeira fase do estudo, numa amostra ao acaso de 38 propriedades, descreveu-se o manejo da pastagem e do rebanho, e na segunda, numa amostra menor, de doze propriedades e por um período de 29 meses, avaliou-se o potencial desses dois componentes. As propriedades estudadas desenvolvem uma pecuária de baixa produtividade. Devido à baixa fertilidade do solo e o deficiente manejo, as pastagens não suprem os alimentos necessários ao rebanho, tanto em quantidade como em qualidade. Também foram identificadas deficiências no manejo do rebanho, próprias de sistemas extensivos. Contudo, as limitações podem ser solucionadas com práticas amplamente conhecidas de manejo da pastagem (como formação, manutenção e manejo) e do rebanho (reprodução, manejo de bezerros e sanidade em geral). Novos modelos de exploração também foram sugeridos