246 research outputs found
is it time to move forward?
Funding: This research was supported by Projects PEst-OE/AGR/UI0211/2011 from FCT, and COMPETE 2020, from ANI – Projetos ID&T Empresas em Copromoção, by the project “insitu.Biomas – Reinvent biomanufacturing systems by using an usability approach for in situ clinic temporary implants fabrication” with the reference POCI-01-0247-FEDER-017771, by the project “Print-on-Organs – Engineering bioinks and processes for direct printing on organs” with the reference POCI-01-0247-FEDER-033877, and by the project “Bone2Move – Development of “in vivo” experimental techniques and modelling methodologies for the evaluation of 4D scafolds for bone defect in sheep model: an integrative research approach” with the reference POCI-01-0145-FEDER-031146. Mariana Vieira Branquinho (SFRH/BD/146172/2019), Ana Catarina Sousa (SFRH/BD/146689/2019), and Rui Damásio Alvites (SFRH/BD/116118/2016), acknowledge FCT, for financial support.INTRODUCTION: Central airway obstruction (CAO) represents a pathological condition that can lead to airflow limitation of the trachea, main stem bronchi, bronchus intermedius or lobar bronchus. MAIN BODY: It is a common clinical situation consensually considered under-diagnosed. Management of patients with CAO can be difficult and deciding on the best treatment approach represents a medical challenge. This work intends to review CAO classifications, causes, treatments and its therapeutic limitations, approaching benign and malign presentations. Three illustrative cases are further presented, supporting the clinical problem under review. CONCLUSION: Management of CAO still remains a challenge. The available options are not always effective nor free from complications. A new generation of costume-tailored airway stents, associated with stem cell-based therapy, could be an option in specific clinical situations.publishersversionpublishe
Thienylpyrrole azo dyes: synthesis, solvatochromic and electrochemical properties
The synthesis and the evaluation of solvatochromic and electrochemical properties of new donor-acceptor-substituted thienylpyrrole azo dyes 3 are described. These derivatives exhibit dramatic changes in both their electronic and redox properties in comparison with thienylpyrroles 1. In agreement with the solvatochromic and electrochemical studies of push-pull derivatives 3 the new compounds prepared, may find application in the manufacture of new materials with notable non-linear optical properties.Fundação para a Ciència e Tecnologia - POCTI/QUI/37816/2001
Donor-acceptor substituted thienylpyrrole azo dyes: synthesis, solvatochromic and electrochemical properties
The synthesis of thienyl- substituted pyrrole azo dyes and their UV-visible, solvatochromic and electrochemical properties are described. In agreement with the solvatochromic data and also with the electrochemical study the new donor-acceptor systems synthesized could have applications in NLO.Fundação para a Ciência e Tecnologia (FCT
Synthesis of formyl-thienylpyrroles : versatile building blocks for NLO materials
Several formyl-substituted 1-alkyl(aryl)-2-(2´-thienyl)pyrroles 3-7 were synthesized by functionalization of the pyrrole or thiophene ring of thienylpyrroles 2 using different methods: Vilsmeier formylation or metalation followed by reaction with DMF.Fundação para a Ciência e Tecnologi
Simultaneous transfer of cholesterol, triglycerides, and phospholipids to high-density lipoprotein in aging subjects with or without coronary artery disease
OBJECTIVE: To verify whether the capacity of high-density lipoprotein (HDL) to simultaneously receive nonesterified cholesterol, triglycerides, cholesteryl esters, and phospholipids changes with aging and the presence of coronary artery disease. DESIGN: Cross-sectional study with biochemical analyses. SUBJECTS: Eleven elderly patients with coronary artery disease (74±5 years) were compared with the following groups of non-coronary artery disease subjects (referred to as "healthy"): 25 young (25±5 years), 25 middle-aged (42± years), and 25 elderly subjects (75±8 years). METHODS: Plasma samples were incubated with a nanoemulsion labeled with radioactive lipids; the transfer of the lipids from the nanoemulsion to the HDL was measured in chemically precipitated HDL. HDL size and paraoxonase-1 activity were also determined. RESULTS: The transfer of cholesteryl esters and phospholipids to high-density lipoprotein was significantly greater (p<0.001) in healthy elderly subjects than in the middle-aged and younger subjects. Non-esterified cholesterol and triglyceride transfer was not different among these three groups. The HDL size was significantly greater (p<0.001) in healthy elderly subjects than in the middle-aged and younger subjects. The paraoxonase-1 activity was similar among the groups. Compared with healthy elderly subjects, coronary artery disease elderly subjects had significantly less (p<0.05) transfer of non-esterified cholesterol, triglycerides, and cholesteryl esters to the HDL and a significantly smaller (p<0.05) HDL size. CONCLUSION: Because lipid transfer is enhanced in healthy elderly subjects but not in those with coronary artery disease, increasing lipid transfer to HDL may be a protective mechanism against the disease
Synthesis and UV-visible properties of thienyl- substituted pyrrole azo dyes
The synthesis of thienyl- substituted pyrrole azo dyes and their UV-visible properties are described.Fundação para a Ciência e Tecnologia.
FEDER - POCTI/QUI/37816/2001.Thanks are due to Foundation for Science and Technology (Portugal) for financial support through IBQF (UM) and through FEDER, POCTI (ref. POCTI/QUI/37816/2001)
Synthesis of tricyanovinyl-substituted thienylpyrroles and characterization of the solvatochromic, electrochemical and non-linear optical properties
Tricyanovinyl-substituted 1-(alkyl)aryl-2-(2´-thienyl)pyrroles 1 have been synthesized by direct tricyanovinylation reaction of 1-(alkyl)aryl-2-(2´-thienyl)pyrroles 2 using TCNE. The tricyanovinyl- derivatives 1 display dramatic reductions in both their optical and electrochemical band gaps relative to thienylpyrrole precursors 2. The solvatochromic behavior of compounds 1 was investigated in a variety of solvents. Hyper-Rayleigh scattering was used to measure the first hyperpolarizabilities β of the mentioned compounds. The β values show that the new compounds prepared could be used on the manufacture of materials with good non-linear (NLO) properties.Fundação para a Ciência e Tecnologia (FCT) - POCTI, FEDER (ref.POCTI/QUI/37816/2001)
3D printed Poly(ε-caprolactone)/Hydroxyapatite scaffolds for bone tissue engineering: a comparative study on a composite preparation by melt blending or solvent casting techniques and the influence of bioceramic content on scaffold properties
Bone tissue engineering has been developed in the past decades, with the engineering of bone substitutes on the vanguard of this regenerative approach. Polycaprolactone-based scaffolds are fairly applied for bone regeneration, and several composites have been incorporated so as to improve the scaffolds’ mechanical properties and tissue in-growth. In this study, hydroxyapatite is incorporated on polycaprolactone-based scaffolds at two different proportions, 80:20 and 60:40. Scaffolds are produced with two different blending methods, solvent casting and melt blending. The prepared composites are 3D printed through an extrusion-based technique and further investigated with regard to their chemical, thermal, morphological, and mechanical characteristics. In vitro cyto-compatibility and osteogenic differentiation was also assessed with human dental pulp stem/stromal cells. The results show the melt-blending-derived scaffolds to present more promising mechanical properties, along with the incorporation of hydroxyapatite. The latter is also related to an increase in osteogenic activity and promotion. Overall, this study suggests polycaprolactone/hydroxyapatite scaffolds to be promising candidates for bone tissue engineering, particularly when produced by the MB method.info:eu-repo/semantics/publishedVersio
Gamma Irradiation Processing on 3D PCL Devices—A Preliminary Biocompatibility Assessment
Funding Information: Mariana Vieira Branquinho (SFRH/BD/146172/2019), Ana Catarina Sousa (SFRH/BD/146689/2019), and Bruna Lopes (2021.05265.BD) acknowledge the Fundação para a Ciência e Tecnologia (FCT)’s financial support. Rui Damásio Alvites acknowledges the Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), Porto University (UP), and FCT for the funding and availability of all technical, structural, and human resources necessary for the development of this work. The work was supported through the project UIDB/00211/2020 funded by FCT/MCTES, national funds. This research was funded by Projects PEst-OE/AGR/UI0211/2011 from FCT, and COMPETE 2020, from ANI–Projetos ID&T Empresas em Copromoção, by the project “Print-on-Organs–Engineering bioinks and processes for direct printing on organs” with the reference POCI-01-0247-FEDER-033877, by the project “Bone2Move-Development of “in vivo” experimental tech-niquesand modelling methodologies for the evaluation of 4D scaffolds for bone defect in sheepmodel: an integrative research approach” with the reference POCI-01-0145-FEDER-031146. Publisher Copyright: © 2022 by the authors.Additive manufacturing or 3D printing applying polycaprolactone (PCL)-based medical devices represents an important branch of tissue engineering, where the sterilization method is a key process for further safe application in vitro and in vivo. In this study, the authors intend to access the most suitable gamma radiation conditions to sterilize PCL-based scaffolds in a preliminary biocompatibility assessment, envisioning future studies for airway obstruction conditions. Three radiation levels were considered, 25 kGy, 35 kGy and 45 kGy, and evaluated as regards their cyto- and biocompatibility. All three groups presented biocompatible properties, indicating an adequate sterility condition. As for the cytocompatibility analysis, devices sterilized with 35 kGy and 45 kGy showed better results, with the 45 kGy showing overall improved outcomes. This study allowed the selection of the most suitable sterilization condition for PCL-based scaffolds, aiming at immediate future assays, by applying 3D-customized printing techniques to specific airway obstruction lesions of the trachea.publishersversionpublishe
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