New prospects in skin regeneration and repair using nanophased hydroxyapatite embedded in collagen nanofibers

This study reflects an exploitation of a composite matrix produced by electrospinning of collagen and electrospraying of nanophased hydroxyapatite (nanoHA), for skin regeneration applications. The main goal was to evaluate the effect of nanoHA, as source of localized calcium delivery, on human dermal fibroblasts, keratinocytes, and human mesenchymal stem cells (hMSCs) growth, proliferation, differentiation, and extracellular matrix production. This study revealed that calcium ions provided by nanoHA significantly enhanced cellular growth and proliferation rates and prevented adhesion of pathogenic bacteria strains typically found in human skin flora. Moreover, hMSCs were able to differentiate in both osteogenic and adipogenic lineages. Rat subcutaneous implantation of the membranes also revealed that no adverse reaction occurred. Therefore, the mechanically fit composite membrane presents a great potential to be used either as cell transplantation scaffold for skin wound regeneration or as wound dressing material in plastic surgery, burns treatment or skin diseases.info:eu-repo/semantics/acceptedVersio

Polymeric biomaterials for wound healing

Skin indicates a person’s state of health and is so important that it influences a person’s emotional and psychological behavior. In this context, the effective treatment of wounds is a major concern, since several conventional wound healing materials have not been able to provide adequate healing, often leading to scar formation. Hence, the development of innovative biomaterials for wound healing is essential. Natural and synthetic polymers are used extensively for wound dressings and scaffold production. Both natural and synthetic polymers have beneficial properties and limitations, so they are often used in combination to overcome overcome their individual limitations. The use of different polymers in the production of biomaterials has proven to be a promising alternative for the treatment of wounds, as their capacity to accelerate the healing process has been demonstrated in many studies. Thus, this work focuses on describing several currently commercially available solutions used for the management of skin wounds, such as polymeric biomaterials for skin substitutes. New directions, strategies, and innovative technologies for the design of polymeric biomaterials are also addressed, providing solutions for deep burns, personalized care and faster healing.This research was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, and by LABBELS—Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020. This study was also funded by program Marie Skłodowska-Curie grant (MSCA-RISE; FODIAC; 778388), and by the European Regional Development Fund (ERDF) through the Competitiveness factors Operational program—Norte 2020, COMPETE and by National Funds through the FCT—under the project AgriFood XXI (NORTE- 01-0145-FEDER-000041)

Hypoglycemia in elderly diabetic patients: experience in a diabetes unit

Introdução: Assiste-se atualmente a uma evolução paralela do envelhecimento da população e da prevalência crescente de Diabetes Mellitus. Os indivíduos idosos estão particularmente susceptíveis à ocorrência de episódios de hipoglicemia, responsáveis por uma morbimortalidade significativa nesta população. Os objetivos do estudo foram a avaliação da incidência de doentes diabéticos com episódios de hipoglicemia na população de idosos seguidos na Unidade Integrada de Diabetes (UID) do HFF e caracterizar, comparativamente, a população de idosos com e sem episódios de hipoglicemia. Materiais e métodos: Estudo observacional, longitudinal, retrospetivo, descritivo, consistindo na análise de variáveis demográficas, clínicas e laboratoriais constantes em processo clínico informático Soarian®, num período de um ano, procedendo-se a análise estatística dos mesmos. Resultados: Em 2013 mais de metade dos doentes seguidos na UID eram idosos, tendo-se verificado episódios de hipoglicemia em 22,6%. A maioria dos doentes com episódios de hipoglicemia (CH) tratava-se de doentes com mais de 75 anos e tinha um tempo de evolução de doença superior a 5 anos, com uma média de tempo de evolução de 17,5 anos. A presença de complicações microvasculares foi objetivada em mais de metade destes doentes (51,2%) sendo que 47,8% apresentavam complicações macrovasculares. A HbA1C média era de 7,8%, tendo apresentado, ao longo do ano, uma descida média de 0,6%. A maioria (71,7%) dos doentes CH estava medicado com insulina, mais de metade destes (54,3%) medicados com insulina com pico de ação, tratando-se de proporções significativamente superiores às objetivadas nos doentes sem episódios de hipoglicemia (SH). Relativamente ao uso de antidiabéticos orais, 26,1% estavam medicados com sulfonilureias. Conclusão: Este estudo vem reiterar a necessidade de individualização e adequação de objetivos de cuidados na população idosa e com mais comorbilidades, assumindo alvos glicémicos mais permissivos e esquemas terapêuticos com menor risco associado de hipoglicemia.info:eu-repo/semantics/publishedVersio

Development and characterization of a novel hybrid tissue engineering-based scaffold for spinal cord injury repair

Spinal cord injury (SCI) represents a significant health and social problem, and therefore it is vital to develop novel strategies that can specifically target it. In this context, the objective of the present work was to develop a new range of three-dimensional (3D) tubular structures aimed at inducing the regeneration within SCI sites. Up to six different 3D tubular structures were initially developed by rapid prototyping: 3D bioplotting–based on a biodegradable blend of starch. These structures were then further complemented by injecting Gellan Gum, a polysaccharide-based hydrogel, in the central area of structures. The mechanical properties of these structures were assessed using dynamic mechanical analysis, under both dry and wet conditions, and their morphologies= porosities were analyzed using micro-computed tomography and scanning electron microscopy. Biological evaluation was carried out to determine their cytotoxicity, using both minimum essential medium (MEM) extraction and MTS tests, as well as by encapsulation of an oligodendrocyte-like cell (M03-13 cell line) within the hydrogel phase. The histomorphometric analysis showed a fully interconnected network of pores with porosity ranging from 70% to 85%. Scaffolds presented compressive modulus ranging from 17.4 to 62.0MPa and 4.42 to 27.4 MPa under dry and wet conditions, respectively. Cytotoxicity assays revealed that the hybrid starch=poly-ecaprolactone= Gellan Gum scaffolds were noncytotoxic, as they did not cause major alterations on cell morphology, proliferation, and metabolic viability. Moreover, preliminary cell encapsulation assays showed that the hybrid scaffolds could support the in vitro culture of oligodendrocyte-like cells. Finally, preliminary in vivo studies conducted in a hemisection rat SCI model revealed that the above-referred structures were well integrated within the injury and did not trigger chronic inflammatory processes. The results herein presented indicate that these 3D systems might be of use in future SCI regeneration approaches.Portuguese Foundation for Science and Technology through funds from Programa Operacional Ciencia, Tecnologia, Inovacao (POCTI) and/or Fundo Europeu de Desenvolvimento Regional (FEDER) programs (funding to ICVS, 3B's Research Group, predoctoral and postdoctoral fellowships to N. A. Silva, J. T. Oliveira, A. J. Salgado, and R. A. Sousa-SFRH/BD/40684/2007; SFRH/BD/17135/2004; SFRH/BPD/17595/2004; SFRH/BPD/17151/2004)

Deteção remota multiespectral e hiperespetral como fonte de conhecimento no sector português da Faixa Piritosa Ibérica

ABSTRACT: Remote sensing is an invaluable tool to increase geological and mining knowledge, due to its screening view and variable discrimination and identification capabilities of the target materials. In this study an overview of remote sensing research developed and ongoing within the Portuguese sector of the Iberian Pyrite Belt (PSIPB) since 2000 is given. Multispectral and hyperspectral datasets were processed using hybrid methods, related both to general and detailed characterization, to: 1) support geological, mineral and hydrothermal mapping, 2) generate products derived from multivariate analysis and band ratios, 3) enhance correlation with radiometric data, 4) provide elements for environmental assessment concerning mining activity, 5) map Acid Mine Drainage (AMD) based on spectral field signatures, 6) quantify AMD based on high correlation mineralogical mapping, and 7) monitor AMD. The results highlight the importance of the quantitative digital support given by remote sensing tools within the Portuguese Sector of the Iberian Pyrite Belt (PSIPB), ruled by georesource exploitation in different stages of the Mine Lyfe Cycle.RESUMO: A deteção remota é uma ferramenta valiosa para aumentar o conhecimento geológico e mineiro, devido à visão sinótica e à capacidade variável de discriminação e identificação dos materiais-alvo. Neste trabalho dá-se uma visão geral da investigação através dos trabalhos de deteção remota desenvolvidos e em curso no Setor Português da Faixa Piritosa Ibérica (SPFPI) desde 2000. Os dados multiespectrais e hiperespectrais foram processados usando métodos híbridos quer para a sua caracterização geral quer detalhada para: 1) apoiar a cartografia geológica, de mineralizações e sistemas hidrotermais, 2) gerar produtos de análise multivariada e rácios de bandas, 3) melhorar a correlação com dados radiométricos 4) fornecer elementos para avaliação ambiental em áreas mineiras, 5) cartografar a drenagem ácida de mina (DAM) com assinaturas espectrais de campo, 6) quantificar a DAM através de cartografia mineralógica de alta correlação, e 7) monitorizar a DAM. Destaca-se a importância do suporte digital quantitativo dado por ferramentas de deteção remota no SPFPI, regido pela exploração de georrecursos em diferentes fases do Ciclo de Vida das Minas.info:eu-repo/semantics/publishedVersio

Injectable and tunable hyaluronic acid hydrogels releasing chemotactic and angiogenic growth factors for endodontic regeneration

Bioengineered soft tissues on any meaningful scale or complexity must incorporate aspects of the functional tissue, namely a vasculature, providing cells oxygen and nutrients critical for their survival. However, the ability of tissue engineering strategies to promote a fast revascularization is critically limited. Particularly in endodontic regenerative therapies, the complicated anatomy of the root canal system, and the narrow apical access limit the supply of new blood vessels and pulp tissue ingrowth. Here we characterize the viscoelastic and microstructural properties of a class of injectable hyaluronic acid (HA) hydrogels formed in situ, reinforced with cellulose nanocrystals (CNCs) and enriched with platelet lysate (PL), and test its ability to promote cells recruitment and proangiogenic activity in vitro. The incorporation of CNCs enhanced the stability of the materials against hydrolytic and enzymatic degradation. Moreover, the release of the chemotactic and pro-angiogenic growth factors (GFs) (PDGF and VEGF) from the PL-laden hydrogels showed an improved sustained profile proportional to the amount of incorporated CNCs. The PL-laden hydrogels exhibited preferential supportive properties of encapsulated human dental pulp cells (hDPCs) in in vitro culture conditions. Finally, PL-laden hydrogels stimulated chemotactic and pro-angiogenic activity by promoting hDPCs recruitment and cell sprouting in hDPCs/human umbilical vein endothelial cell co-cultures in vitro, and in an ex vivo model. These results support the use of the combined system as a scaffold for GFs delivery and cells recruitment, thereby exhibiting great clinical potential in treating injuries in vascularized tissues.RECOGNIZE project (UTAP-ICDT/CTM-BIO/0023/2014), project NORTE-01-0145-FEDER-000021. R.M.A. Domingues acknowledges FCT for SFRH/BPD/112459/2015. P.S. Babo acknowledges the project FOOD4CELLS (PTDC/CTM-BIO/4706/2014-POCI-01-0145-FEDER 016716) for his post-doc grantinfo:eu-repo/semantics/publishedVersio

Neurodifferentiation and neuroprotection potential of mesenchymal stromal cell-derived secretome produced in different dynamic systems

Parkinson’s disease (PD) is the second most common neurodegenerative disorder and is characterized by the degeneration of the dopamine (DA) neurons in the substantia nigra pars compacta, leading to a loss of DA in the basal ganglia. The presence of aggregates of alpha-synuclein (α-synuclein) is seen as the main contributor to the pathogenesis and progression of PD. Evidence suggests that the secretome of mesenchymal stromal cells (MSC) could be a potential cell-free therapy for PD. However, to accelerate the integration of this therapy in the clinical setting, there is still the need to develop a protocol for the large-scale production of secretome under good manufacturing practices (GMP) guidelines. Bioreactors have the capacity to produce large quantities of secretomes in a scalable manner, surpassing the limitations of planar static culture systems. However, few studies focused on the influence of the culture system used to expand MSC, on the secretome composition. In this work, we studied the capacity of the secretome produced by bone marrow-derived mesenchymal stromal cells (BMSC) expanded in a spinner flask (SP) and in a Vertical-Wheel™ bioreactor (VWBR) system, to induce neurodifferentiation of human neural progenitor cells (hNPCs) and to prevent dopaminergic neuron degeneration caused by the overexpression of α-synuclein in one Caenorhabditis elegans model of PD. Results showed that secretomes from both systems were able to induce neurodifferentiation, though the secretome produced in the SP system had a greater effect. Additionally, in the conditions of our study, only the secretome produced in SP had a neuroprotective potential. Lastly, the secretomes had different profiles regarding the presence and/or specific intensity of different molecules, namely, interleukin (IL)-6, IL-4, matrix metalloproteinase-2 (MMP2), and 3 (MMP3), tumor necrosis factor-beta (TNF-β), osteopontin, nerve growth factor beta (NGFβ), granulocyte colony-stimulating factor (GCSF), heparin-binding (HB) epithelial growth factor (EGF)-like growth factor (HB-EGF), and IL-13. Overall, our results suggest that the culture conditions might have influenced the secretory profiles of cultured cells and, consequently, the observed effects. Additional studies should further explore the effects that different culture systems have on the secretome potential of PD.This work has been funded by la Caixa Foundation and Portuguese Foundation for Science and Technology (FCT) under the agreement LCF/PR/HP20/52300001; ICVS Scientific Microscopy Platform, member of the national infrastructure PPBI—Portuguese Platform of Bioimaging (PPBI-POCI-01-0145-FEDER-022122); by National funds, through the Foundation for Science and Technology (FCT)—project UIDB/50026/2020 and UIDP/50026/2020. CRM was supported by a Ph.D. scholarship from FCT and the company Stemmatters, Biotecnologia e Medicina Regenerativa SA (PD/BDE/127833/2016). Funding received by iBB-Institute for Bioengineering and Biosciences from FCT (UID/BIO/04565/2020) and through the project PTDC/EQU-EQU/31651/2017 is acknowledged. MAF was supported by a Ph.D. scholarship from FCT (SFRH/PD/BD/128328/2017). RC was supported by the EXOpro project (PTDC/EQU-QUE/31651/2017). JPS was supported by a Ph.D. scholarship from FCT and the company Bn’ML—Behavioral & Molecular Lab (PD/BDE/127834/2016). DS was supported by a Ph.D. scholarship from FCT and the company Stemmatters, Biotecnologia e Medicina Regenerativa S.A. (PD/BDE/135567/2018) JC was supported by a Ph.D. scholarship from FCT (SFRH/BD/5813/2020)

A practical clinical score

Copyright © 2022 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.INTRODUCTION AND OBJECTIVES: Obstructive coronary artery disease (CAD) remains the most common etiology of heart failure with reduced ejection fraction (HFrEF). However, there is controversy whether invasive coronary angiography (ICA) should be used initially to exclude CAD in patients presenting with new-onset HFrEF of unknown etiology. Our study aimed to develop a clinical score to quantify the risk of obstructive CAD in these patients. METHODS: We performed a cross-sectional observational study of 452 consecutive patients presenting with new-onset HFrEF of unknown etiology undergoing elective ICA in one academic center, between January 2005 and December 2019. Independent predictors for obstructive CAD were identified. A risk score was developed using multivariate logistic regression of designated variables. The accuracy and discriminative power of the predictive model were assessed. RESULTS: A total of 109 patients (24.1%) presented obstructive CAD. Six independent predictors were identified and included in the score: male gender (2 points), diabetes (1 point), dyslipidemia (1 point), smoking (1 point), peripheral arterial disease (1 point), and regional wall motion abnormalities (3 points). Patients with a score ≤3 had less than 15% predicted probability of obstructive CAD. Our score showed good discriminative power (C-statistic 0.872; 95% CI 0.834-0.909: p<0.001) and calibration (p=0.333 from the goodness-of-fit test). CONCLUSIONS: A simple clinical score showed the ability to predict the risk of obstructive CAD in patients presenting with new-onset HFrEF of unknown etiology and may guide the clinician in selecting the most appropriate diagnostic modality for the assessment of obstructive CAD.proofepub_ahead_of_prin

2,4,5-Triaminopyrimidines as blue fluorescent probes for cell viability monitoring: synthesis, photophysical properties, and microscopy applications

Monitoring cell viability is critical in cell biology, pathology, and drug discovery. Most cell viability assays are cell-destructive, time-consuming, expensive, and/or hazardous. Herein, we present a series of newly synthesized 2,4,5-triaminopyrimidine derivatives able to discriminate between live and dead cells. To our knowledge, these compounds are the first fluorescent nucleobase analogues (FNAs) with cell viability monitoring potential. These new fluorescent molecules are synthesized using highly efficient and cost- effective methods and feature unprecedented photophysical properties (longer absorption and emission wavelengths, environment-sensitive emission, and unprecedented brightness within FNAs). Using a live– dead Saccharomyces cerevisiae cell and theoretical assays, the fluorescent 2,4,5-triaminopyrimidine derivatives were found to specifically accumulate inside dead cells by interacting with dsDNA grooves, thus paving the way for the emergence of novel and safe fluorescent cell viability markers emitting in the blue region. As the majority of commercially available viability dyes emit in the green to red region of the visible spectrum, these novel markers might be useful to meet the needs of blue markers for co-staining combinations