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This study aimed to improve the performance and mode of administration of a glass-reinforced hydroxyapatite synthetic bone substitute, Bonelike by Biosckin® (BL®), by association with a dextrin-based hydrogel, DEXGEL, to achieve an injectable and moldable device named DEXGEL Bone., Open access funding provided by FCT|FCCN (b-on). The authors were funded by FEDER and NORTE 2020 through project no. 003262 titled “iBONE therapies: advanced solutions for bone regen eration.” This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of the UID/BIO/04469 unit and COMPETE 2020 (POCI-01–0145- FEDER-006684) and BioTecNorte operation (NORTE-01–0145- FEDER-000004) funded by the European Regional Development Fund under the scope of Norte 2020—Programa Operacional Regional do Norte. The authors were granted a scholarship (SFRH/BD/132000/2017) by Portuguese FCT. This work was also funded by project UIDB/CVT/00772/2020 supported by FCT., info:eu-repo/semantics/publishedVersion

Dry or powdered formulations of food additives facilitate transportation, storage, preservation and handling. In this work, dry formulations of bacterial cellulose and carboxymethyl cellulose (BC:CMC), easily redispersible and preserving the functionality of the never-dried dispersions are reported. Different processing parameters and their effect on the materials properties were evaluated, namely: (i) wet-grinding of BC (Hand-blender, Microcut Head Impeller, High-pressure Homogenizer), (ii) drying of BC:CMC mixtures (fast drying at130 °C and slow drying at 80 °C) and subsequent (iii) comminution to different particle sizes. The dispersibility of the obtained BC:CMC powders was evaluated, and their functionality after redispersion was assessed by measuring the dynamic viscosity, the effect in oil/water interfacial tension (liquidliquid system) and the stabilization of cocoa in milk (solidliquid system). The size of BC fibre bundles was of paramount relevance to its stabilizing ability in multiphasic systems. A more extensive wet-grinding of the BC fibres was accompanied by a loss in the BC:CMC functionality, related to the increasingly smaller size of the BC bundles. Indeed, as the Dv (50) of the wet BC bundles was reduced from 1228 to 55 µm, the BC:CMC viscosity profile dropped and the effect on interfacial tension decreased. This effect was observed both on the never-dried and dry BC:CMC formulations. On the other hand, the drying method did not play a major effect in the materials properties. In a benchmarking study, the BC:CMC formulations, at a low concentration (0.15%), had better stabilizing ability of the cocoa particles than several commercial cellulose products., Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10570-020-03211-9) contains supplementary material, which is available to authorized users., This study was supported by FCT under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER000004) funded by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte. Daniela Martins also gratefully acknowledges FCT for the PhD scholarship, reference SFRH/BD/115917/2016., info:eu-repo/semantics/publishedVersion

A new strategy for the surface modification of bacterial cellulose (BC) through the combination of oxygen plasma deposition and silanization with trichloromethyl silane (TCMS) is described. The combined use of the two techniques modifies both the surface roughness and energy and therefore maximizes the obtained hydrophobic effect. These modified membranes were characterized by Scanning Electron Microscopy (SEM), water contact angle measurements, Fourier-transform infrared spectroscopy (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS), and its cytotoxic potential was investigated using both indirect and direct contact in vitro studies. The obtained results suggest an effective conjugation of TCMS to the surface of BC, leading to a highly hydrophobic surface, with a water contact angle of approximately 130º. It is also demonstrated that this is a stable and durable surface modification strategy, since BC remained hydrophobic even after 6 months, in dry conditions or after being submerged in distilled water for about a month. Importantly, this surface modification revealed no short-term cytotoxic effects on L929 and hDNFs cells. Altogether, these data indicate the successful development of a surface modification method that can be applied to BC, enabling the production of a biodegradable and hydrophobic platform that can be applied to different areas of research and industry., This work was supported by the Fundação para a Ciência e a Tecnologia (FCT), under the project ‘‘SkinChip: Disruptive cellulose-based microfluidic device for 3D skin modelling’’ (PTDC/BBB-BIO/1889/2014, SFRH/BPD/121526/2016), co-financed by the Lisboa 2020, COMPETE 2020, Portugal 2020 and the BioTecNorte operation (NORTE01-0145-FEDER-000004) with funding by the European Regional Development Fund under the scope of Norte2020— Programa Operacional Regional do Norte., info:eu-repo/semantics/publishedVersion

In view of the growing industrial use of Bacterial cellulose (BC), and taking into account that it might become airborne and be inhaled after industrial processing, assessing its potential pulmonary toxic effects assumes high relevance. In this work, the murine model was used to assess the effects of exposure to respirable BC nanofibrils (nBC), obtained by disintegration of BC produced by Komagataeibacter hansenii. Murine bone marrow-derived macrophages (BMM) were treated with different doses of nBC (0.02 and 0.2 mg/mL, respectively 1 and 10 g of fibrils) in absence or presence of 0.2% Carboxymethyl Cellulose (nBCMC). Furthermore, mice were instilled intratracheally with nBC or nBCMC at different concentrations and at different time-points and analyzed up to 6 months after treatments. Microcrystaline Avicel-plus® CM 2159, a plant-derived cellulose, was used for comparison. Markers of cellular damage (lactate dehydrogenase release and total protein) and oxidative stress (hydrogen peroxidase, reduced glutathione, lipid peroxidation and glutathione peroxidase activity) as well presence of inflammatory cells were evaluated in brochoalveolar lavage (BAL) fluids. Histological analysis of lungs, heart and liver tissues was also performed. BAL analysis showed that exposure to nBCMC or CMC did not induce major alterations in the assessed markers of cell damage, oxidative stress or inflammatory cell numbers in BAL fluid over time, even following cumulative treatments. Avicel-plus® CM 2159 significantly increased LDH release, detected 3 months after 4 weekly administrations. However, histological results revealed a chronic inflammatory response and tissue alterations, being hypertrophy of pulmonary arteries (observed 3 months after nBCMC treatment) of particular concern. These histological alterations remained after 6 months in animals treated with nBC, possibly due to foreign body reaction and the organisms inability to remove the fibers. Overall, despite being a safe and biocompatible biomaterial, BC-derived nanofibrils inhalation may lead to lung pathology and pose significant health risks., The authors acknowledge Embrapa Tropical Agroindustry and Coordination for the Improvement of Higher Education Personnel (CAPES) and the project under the bilateral program FCT/CAPES: Bacterial Cellulose: a platform for the development of bionanoproducts for funding this research. This work was also financially supported by: European Investment Funds by FEDER/COMPETE/POCI - Operational Competitiveness and Internationalization Program, under Project POCI-01-0145-FEDER-006958, National Funds by FCT - Portuguese Foundation for Science and Technology, Project POCI-01-0145-FEDER-006939 (Laboratory for Process Engineering, Environment, Biotechnology and Energy - LEPABE funded by FEDER, funds through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) - and by national funds through FCT. Rui Gil da Costa is supported by grant nº SFRH/BPD/85462/2012 from FCT, financed by the Portuguese Government and the Social European Fund. This study was supported by the Portuguese Foundation for Science and Technology (FCT) also under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte., info:eu-repo/semantics/publishedVersion

In this work, films based on bacterial cellulose nanofibers (BCNFs) incorporating gelatin hydrolysate (GH) from tilapia skin were produced. The effect of plasticizer (sorbitol or glycerol) and GH incorporation was evaluated on the physicalchemical and optical properties of films. BCNFs were produced using bacterial cellulose obtained from Hestrin and Schramm (HS) medium (BCNF-HS) or cashew apple juice (BCNF-CM), which was studied as an alternative to HS. Films with sorbitol showed the best properties and were selected for further characterization, using 40% (w/w) of BCNF-HS, 40% (w/w) of GH and 20% (w/w) of sorbitol (BCNF-HS-S-GH films). These films exhibited an antioxidant activity of 7.8 µmols Trolox Eq/g film, a water vapor permeability (WVP) of 1.6 g.mm/kPa.h.m2 and an Youngs modulus of 0.57 GPa. Films produced with BCNFs obtained from cashew apple juice revealed enhanced tensile strength, elongation at break, and thermal stability. Caco-2 cells viability after incubation with BCNF-based films incorporating GH was evaluated and showed non-cytotoxicity, reinforcing the safety of the developed materials and their potential use in food applications., The authors would like to thank: Foundation of Support to the Scientific and Technological Development (FUNCAP, Brazil), Coordination for the Improvement of Higher Education Personnel (CAPES, Brazil), National Counsel of Technological and Scientific Development (CNPq, Brazil), Minho University (Braga, Portugal) and International Iberian Nanotechnology Laboratory (Braga, Portugal). This work was funded by research projects CNPq n 485465/2012-4, CNPq n 310368/2012-0 and CNPq n 476978/2013-0. Funding from Fundac¸a ˜o para a Cie ˆncia e Tecnologia through the project ‘‘Bacterial Cellulose: a platform for the development of bionanoproducts’’, under the bilateral program FCT/CAPES, is acknowledged. The authors acknowledge also the funding from QREN (‘‘Quadro de Referência Estratégica Nacional’’), ADI (‘‘Agência de Inovação’’) through the project Norte-070202-FEDER-038853, and BioTecNorte operation (NORTE01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte. This research was supported by Norte Regional Operational Program 2014–2020 (Norte2020) through the European Regional Development Fund (ERDF) Nanotechnology based functional solutions (NORTE-01-0145FEDER-000019)., info:eu-repo/semantics/publishedVersion

Green Public Procurement (GPP) is currently being used to influence the market to shift to a supply of goods and services to the public sector that have a reduced environmental impact. The food service sector plays a major role in the purchases made by the public sector and due to that relevance deserves attention. The GPP schemes reviewed were those that provide details of the specific environmental criteria used (or recommended) for public tendering of food products and catering services provision. The set of GPP schemes apply to distinct geographical zones within the EU, including national level (e.g. Italy), regional level (e.g. Barcelona) and also local level, as in the case of cities (e.g. Copenhagen) or schools (e.g. a school in Pisa, Italy). The criteria set covers services provision to schools, health and social care, higher education, government office canteens, sports and leisure arenas, prisons and defence services (e.g. army). European and worldwide GPP criteria were not covered by the review made. This exploratory study comprehends a total of 23 GPP schemes. This sample includes eight national schemes, three regional schemes and ten local schemes. The review focused on the scope, for the sector of applicability (e.g. education, healthcare) of the GPP set of criteria and for the type of food products covered. Moreover, this paper analyses the type of GPP criteria in use and how the environmental criteria cover the distinct life cycle stages of the whole food supply chain. Findings from the analysis show that for the majority of schemes the scope of criteria is simultaneously the provision of food products and catering services. Moreover, cities, municipalities and counties are the main public authorities reporting procurement activities for the education sector while national GPP activities are applicable for multiple sectors of activity. The main food products covered by the criteria are fruits and vegetables, dairy products, fish and seafood and meat. Finally, the findings show that the set of criteria from the schemes cover widely the life cycle stages of the food supply chain. The results allowed for a first identification of current practices in the use of GPP criteria within public purchasing of food products and catering services in Europe by national, regional or local governments.

This work investigates the effect of hot calendering on bacterial cellulose (BC) films properties, aiming the achievement of good transparency and barrier property. A comparison was made using vegetal cellulose (VC) films on a similar basis weight of around 40 g.m-2. The optical-structural, mechanical and barrier property of BC films were studied and compared with those of highly beaten VC films. The Youngs moduli and tensile index of the BC films are much higher than those obtained for VC (14.5 16.2 GPa vs 10.8 8.7 GPa and 146.7 64.8 N.m.g-1 vs 82.8 40.5 N.m.g-1), respectively. Calendering increased significantly the transparency of BC films from 53.0 % to 73.0 %. The effect of BC ozonation was also studied. Oxidation with ozone somewhat enhanced the brightness and transparency of the BC films, but at the expenses of slightly lower mechanical properties. BC films exhibited a low water vapor transfer rate, when compared to VC films and this property decreased by around 70 % following calendering, for all films tested. These results show that calendering could be used as a process to obtain films suitable for food packaging applications, where transparency, good mechanical performance and barrier properties are important. The BC films obtained herein are valuable products that could be a good alternative to the highly used plastics in this industry., The authors thank FCT (Fundação para a Ciência e Tecnologia) and FEDER (Fundo Europeu de Desenvolvimento Regional) for the financial support of the project FCT PTDC/AGR-FOR/3090/2012— FCOMP-01-0124-FEDER-027948 and the awarding of a research grant for Vera Costa.

Biomaterials used for tissue engineering applications must provide a structural support for the tissue development and also actively interact with cells, promoting adhesion, proliferation, and differentiation. To achieve this goal, adhesion molecules may be used, such as the tripeptide Arg-Gly-Asp (RGD). A method based on the use of a carbohydrate-binding module, with affinity for chitin, was tested as an alternative approach to the chemical grafting of bioactive peptides. This approach would simultaneously allow the production of recombinant peptides (alternatively to peptide synthesis) and provide a simple way for the specific and strong adsorption of the peptides to the biomaterial. A fusion recombinant protein, containing the RGD sequence fused to a human chitin-binding module (ChBM), was expressed in E. coli. The adhesion of fibroblasts to reacetylated chitosan (RC) films was the model system selected to analyze the properties of the obtained proteins. Thus, the evaluation of cell attachment and proliferation on polystyrene surfaces and reacetylated chitosan films, coated with the recombinant proteins, was performed using mouse embryo fibroblasts 3T3. The results show that the recombinant proteins affect negatively fibroblasts anchorage to the materials surface, inhibiting its adhesion and proliferation. We also conclude that this negative effect is fundamentally due to the human chitin-binding domain., Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/27359/2006, POCTI/BIO/45356/2002

A method for the gram-scale production of cellulose-binding domains (CBD) through the proteolytic digestion of a commercial nzymatic preparation (Celluclast) was developed. The CBD obtained, isolated from Trichoderma reesei cellobiohydrolase I, is highly pure and heavily glycosylated. The purified peptide has a molecular weight of 8.43 kDa, comprising the binding module, a part of the linker, and about 30% glycosidic moiety. Its properties may thus be different from recombinant ones expressed in bacteria. CBDfluorescein isothiocyanate conjugates were used to study the CBD-cellulose interaction. The presence of fluorescent peptides adsorbed on crystalline and amorphous cellulose fibers suggests that amorphous regions have a higher concentration of binding sites. The adsorption is reversible, but desorption is a very slow process., Fundação para a Ciência e a Tecnologia (FCT)

Schizophrenia is a serious and chronic mental disorder, in which both genetic and environmental factors have a role in the development of the disease. Neuregulin-1 (NRG1) is one of the most established genetic risk factors for schizophrenia, and disruption of NRG1 signaling has been reported in this disorder. We reported previously that NRG1/ErbB4 signaling is inhibited by receptor phosphotyrosine phosphatase-β/ζ (RPTP β/ζ) and that the gene encoding RPTPβ/ζ (PTPRZ1) is genetically associated with schizophrenia. In this study, we examined the expression of RPTPβ/ζ in the brains of patients with schizophrenia and observed increased expression of this gene. We developed mice overexpressing RPTPβ/ζ (PTPRZ1-transgenic mice), which showed reduced NRG1 signaling, and molecular and cellular changes implicated in the pathogenesis of schizophrenia, including altered glutamatergic, GABAergic and dopaminergic activity, as well as delayed oligodendrocyte development. Behavioral analyses also demonstrated schizophrenia-like changes in the PTPRZ1-transgenic mice, including reduced sensory motor gating, hyperactivity and working memory deficits. Our results indicate that enhanced RPTPβ/ζ signaling can contribute to schizophrenia phenotypes, and support both construct and face validity for PTPRZ1-transgenic mice as a model for multiple schizophrenia phenotypes. Furthermore, our results implicate RPTPβ/ζ as a therapeutic target in schizophrenia.