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  1. Article ; Online: Capillary pruning couples tissue perfusion and oxygenation with cardiomyocyte maturation in the postnatal mouse heart

    Ricardo Santamaría / Javier Cruz-Caballero / Polyxeni Gkontra / Alberto Jiménez-Montiel / Cristina Clemente / Juan A. López / María Villalba-Orero / Jesús Vázquez / Andreas Hutloff / Enrique Lara-Pezzi / Alicia G. Arroyo

    Frontiers in Cell and Developmental Biology, Vol

    2023  Volume 11

    Abstract: Introduction: Removal of poorly perfused capillaries by pruning contributes to remodeling the microvasculature to optimize oxygen and nutrient delivery. Blood flow drives this process by promoting the intravascular migration of endothelial cells in ... ...

    Abstract Introduction: Removal of poorly perfused capillaries by pruning contributes to remodeling the microvasculature to optimize oxygen and nutrient delivery. Blood flow drives this process by promoting the intravascular migration of endothelial cells in developing networks, such as in the yolk sac, zebrafish brain or postnatal mouse retina.Methods: In this study, we have implemented innovative tools to recognize capillary pruning in the complex 3D coronary microvasculature of the postnatal mouse heart. We have also experimentally tested the impact of decreasing pruning on the structure and function of this network by altering blood flow with two different vasodilators: losartan and prazosin.Results: Although both drugs reduced capillary pruning, a combination of experiments based on ex vivo imaging, proteomics, electron microscopy and in vivo functional approaches showed that losartan treatment resulted in an inefficient coronary network, reduced myocardial oxygenation and metabolic changes that delayed the arrest of cardiomyocyte proliferation, in contrast to the effects of prazosin, probably due to its concomitant promotion of capillary expansion.Discussion: Our work demonstrates that capillary pruning contributes to proper maturation and function of the heart and that manipulation of blood flow may be a novel strategy to refine the microvasculature and improve tissue perfusion after damage.
    Keywords capillary pruning ; postnatal heart ; vasodilators ; blood flow ; oxygenation ; metabolism ; Biology (General) ; QH301-705.5
    Subject code 610
    Language English
    Publishing date 2023-11-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: New Eunicellin-Type Diterpenes from the Panamanian Octocoral Briareum asbestinum

    Marcelino Gutiérrez / Ricardo Santamaría / José Félix Gómez-Reyes / Héctor M. Guzmán / Javier Ávila-Román / Virginia Motilva / Elena Talero

    Marine Drugs, Vol 18, Iss 2, p

    2020  Volume 84

    Abstract: Gorgonian octocorals are considered a prolific source of secondary metabolites with a wide range of biological activities, including anti-inflammatory activity. In particular, the genus Briareum is known for producing a wealth of diterpenes with complex ... ...

    Abstract Gorgonian octocorals are considered a prolific source of secondary metabolites with a wide range of biological activities, including anti-inflammatory activity. In particular, the genus Briareum is known for producing a wealth of diterpenes with complex chemical structures. The chemical study of the methanolic extract of Briareum asbestinum collected in Bocas del Toro, on the Caribbean side of Panama, led to the isolation of three new eunicellin-type diterpenes: briarellin T ( 1 ), asbestinin 27 ( 2 ), asbestinin 28 ( 3 ) and the previously described asbestinin 17 ( 4 ). The structures of the new compounds were determined by extensive NMR analyses and HRMS. Anti-inflammatory activity assays showed a significant reduction of the pro-inflammatory cytokines TNF-α, IL-6, IL-1β and IL-8 as well as a downregulation of COX-2 expression in LPS-stimulated THP-1 macrophages. These findings support the potential use of these marine compounds as therapeutic agents in the treatment of inflammatory diseases.
    Keywords asbestinins ; briarellins ; eunicellin diterpenes ; briareum ; cytokines ; cyclooxygenase-2 ; Biology (General) ; QH301-705.5
    Subject code 500
    Language English
    Publishing date 2020-01-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article: Discussion on Operational Voltage and Efficiencies of Ionic-Liquid-Based Electrochemical Capacitors

    Santos, Mayara C. G / Glaura G. Silva / Ricardo Santamaría / Paulo F. R. Ortega / Rodrigo L. Lavall

    Journal of physical chemistry. 2019 Mar. 11, v. 123, no. 14

    2019  

    Abstract: In this article, we explore electrical double-layer capacitors (EDLCs) based on ionic liquids (IL), focusing on their stability and efficiencies (Coulombic and energetic). We analyze the conventional voltammetric methods to determine the electrochemical ... ...

    Abstract In this article, we explore electrical double-layer capacitors (EDLCs) based on ionic liquids (IL), focusing on their stability and efficiencies (Coulombic and energetic). We analyze the conventional voltammetric methods to determine the electrochemical stability window, pointing out that a simple analysis of Coulombic efficiency, under different current and voltage conditions in galvanostatic experiments, has the advantage of being more representative for real cells, especially when studied together with energy efficiency. In addition, we study how IL-based EDLCs differ from aqueous and organic ones in terms of energy efficiency correlating with the physicochemical properties of electrolytes. Finally, we discuss the high resistance of this type of EDLC that has a detrimental effect on energy efficiency and cycling performance, even when the Coulombic efficiency is close to 100%.
    Keywords electric potential difference ; electrical equipment ; electrochemistry ; electrolytes ; energy efficiency ; ionic liquids ; physical chemistry ; physicochemical properties
    Language English
    Dates of publication 2019-0311
    Size p. 8541-8549.
    Publishing place American Chemical Society
    Document type Article
    ISSN 1932-7455
    DOI 10.1021/acs.jpcc.8b11607
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: Experimental and Statistical Optimization of the Tensile Strength of Carbon Fibers from Pitches with Different Composition

    Diez, Noel / Clara Blanco / Marcos Granda / Patricia Álvarez / Ricardo Santamaría / Rosa Menéndez

    Industrial & engineering chemistry process design and development. 2017 Mar. 29, v. 56, no. 12

    2017  

    Abstract: A factorial analysis was used to maximize the tensile strength of the carbon fibers obtained from pitch by means of a rational selection of variables and precursor properties. The combined influence of the fiber diameter, the soaking time at the optimum ... ...

    Abstract A factorial analysis was used to maximize the tensile strength of the carbon fibers obtained from pitch by means of a rational selection of variables and precursor properties. The combined influence of the fiber diameter, the soaking time at the optimum stabilization temperature, and the effect of the polycondensation degree of the pitch on the tensile strength of the carbonized fibers was assessed using a factorial design. For the first time, the strong influence of the degree of polycondensation of the parent pitch was evidenced, even though less polycondensed pitches were spun at a higher yield and favored the homogeneous fixation of oxygen during stabilization. Fibers prepared from the most polycondensed pitches exhibited the best values of tensile strength. However, very highly polycondensed pitch compositions may hinder oxygen diffusion and the formation of cross-linked structures during stabilization, leading to a poorer mechanical performance that can be overcome by increasing the stabilization time.
    Keywords carbon fibers ; condensation reactions ; crosslinking ; factor analysis ; oxygen ; process design ; soaking ; temperature ; tensile strength
    Language English
    Dates of publication 2017-0329
    Size p. 3243-3250.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 1484436-9
    ISSN 1520-5045 ; 0888-5885
    ISSN (online) 1520-5045
    ISSN 0888-5885
    DOI 10.1021/acs.iecr.6b04045
    Database NAL-Catalogue (AGRICOLA)

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  5. Article: Morphological changes in graphene materials caused by solvents

    Fernández-García, Laura / Ana M. Pérez-Mas / Clara Blanco / Marcos Granda / Patricia Álvarez / Ricardo Santamaría / Rosa Menéndez

    Colloids and surfaces. 2018 Dec. 05, v. 558

    2018  

    Abstract: The aim of this work is to determine the changes in morphology caused in thermally reduced graphene oxide (rGO) after it has been mixed with organic molecules with different surface properties. The morphology of the dried rGO after being mixed with 16 ... ...

    Abstract The aim of this work is to determine the changes in morphology caused in thermally reduced graphene oxide (rGO) after it has been mixed with organic molecules with different surface properties. The morphology of the dried rGO after being mixed with 16 organic solvents was evaluated using statistically SEM analysis. The results obtained indicate that this process led, in some cases, to an increase both in the number of stacked layers and in the corrugation of each rGO sheet. The largest modifications were obtained after contact with organic solvents undergoing intramolecular interactions mainly governed by the hydrogen-bonding interactions (measured as the Hansen δh parameter) and the dipole-dipole molecular interactions (expressed by the Hansen δp parameter). On the other hand, the morphology of the rGOs remained unaltered when solvents with values of δp + δh in the range 10–26 MPa1/2 were used. These results represent a useful guide for the preparation of graphene-based composites in which the morphology of the graphene in the mixture is a crucial parameter which affects their characteristics.
    Keywords colloids ; graphene ; graphene oxide ; hydrogen bonding ; scanning electron microscopy ; solvents
    Language English
    Dates of publication 2018-1205
    Size p. 73-79.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1500517-3
    ISSN 0927-7757
    ISSN 0927-7757
    DOI 10.1016/j.colsurfa.2018.08.030
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: LiFePO4/Mesoporous Carbon Hybrid Supercapacitor Based on LiTFSI/Imidazolium Ionic Liquid Electrolyte

    Ortega, Paulo F. R / Clara Blanco / Garbas A. dos Santos Junior / Glaura G. Silva / Luciano A. Montoro / Ricardo Santamaría / Rodrigo L. Lavall

    Journal of physical chemistry. 2018 Jan. 25, v. 122, no. 3

    2018  

    Abstract: A hybrid SC prepared with mesoporous carbon as the negative electrode, LiFePO4 as the positive electrode, and a LiTFSI/imidazolium ionic liquid solution as electrolyte is presented. The cell was conceived on the basis that it offers all of the safety ... ...

    Abstract A hybrid SC prepared with mesoporous carbon as the negative electrode, LiFePO4 as the positive electrode, and a LiTFSI/imidazolium ionic liquid solution as electrolyte is presented. The cell was conceived on the basis that it offers all of the safety features of ionic liquids (IL) and LiFePO4, in addition to the advantages of a high energy density device. Most of the high performance hybrids so far reported in the literature employ aqueous or organic electrolytes, whereas studies of hybrid cells based on IL are still rare. Here, a fundamental study was conducted to understand how the different interfaces and mechanisms operate in a hybrid system based on IL electrolyte and how this affects cell performance. This device was mainly characterized using cyclic chronopotentiometry that allows cell voltage and electrode potentials to be simultaneously recorded. By means of this technique, it was possible to evaluate the overall behavior of the hybrid cell and the faradaic and capacitive electrodes simultaneously and to compare it with the performance of selected standard cells. The results show that the cell is able to attain an energy density of 43.3 W h kg–1 at 0.010 A g–1 (C/5 in relation to LiFePO4), while maintaining a good cycling performance.
    Keywords carbon ; electric power ; electrodes ; electrolytes ; energy density ; ionic liquids ; porous media
    Language English
    Dates of publication 2018-0125
    Size p. 1456-1465.
    Publishing place American Chemical Society
    Document type Article
    ISSN 1932-7455
    DOI 10.1021/acs.jpcc.7b09869
    Database NAL-Catalogue (AGRICOLA)

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  7. Article ; Online: Analysis of the antiparasitic and anticancer activity of the coconut palm (Cocos nucifera L. ARECACEAE) from the natural reserve of Punta Patiño, Darién.

    Nicole M Tayler / Cristopher A Boya / Liuris Herrera / Jamie Moy / Michelle Ng / Laura Pineda / Alejandro Almanza / Sara Rosero / Lorena M Coronado / Ricardo Correa / Ricardo Santamaría / Zuleima Caballero / Armando A Durant-Archibold / Kevin J Tidgewell / Marcy J Balunas / William H Gerwick / Alida Spadafora / Marcelino Gutiérrez / Carmenza Spadafora

    PLoS ONE, Vol 14, Iss 4, p e

    2019  Volume 0214193

    Abstract: Cocos nucifera (C. nucifera) (the coconut palm tree) has been traditionally used to fight a number of human diseases, but only a few studies have tested its components against parasites such as those that cause malaria. In this study, C. nucifera samples ...

    Abstract Cocos nucifera (C. nucifera) (the coconut palm tree) has been traditionally used to fight a number of human diseases, but only a few studies have tested its components against parasites such as those that cause malaria. In this study, C. nucifera samples were collected from a private natural reserve in Punta Patiño, Darien, Panama. The husk, leaves, pulp, and milk of C. nucifera were extracted and evaluated against the parasites that cause Chagas' disease or American trypanosomiasis (Trypanosoma cruzi), leishmaniasis (Leishmania donovani) and malaria (Plasmodium falciparum), as well as against a line of breast cancer cells. While there was no activity in the rest of the tests, five and fifteen-minute aqueous decoctions of leaves showed antiplasmodial activity at 10% v/v concentration. Removal of some HPLC fractions resulted in loss of activity, pointing to the presence of synergy between the components of the decoction. Chemical molecules were separated and identified using an ultra-performance liquid chromatography (UPLC) approach coupled to tandem mass spectrometry (LC-MS/MS) using atmospheric pressure chemical ionization quadrupole-time of flight mass spectrometry (APCI-Q-TOF-MS) and molecular networking analysis, revealing the presence of compounds including polyphenol, flavone, sterol, fatty acid and chlorophyll families, among others.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2019-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: A pseudopterane diterpene isolated from the octocoral Pseudopterogorgia acerosa inhibits the inflammatory response mediated by TLR-ligands and TNF-alpha in macrophages.

    Yisett González / Deborah Doens / Ricardo Santamaría / Marla Ramos / Carlos M Restrepo / Luciana Barros de Arruda / Ricardo Lleonart / Marcelino Gutiérrez / Patricia L Fernández

    PLoS ONE, Vol 8, Iss 12, p e

    2013  Volume 84107

    Abstract: Several diterpenoids isolated from terrestrial and marine environments have been identified as important anti-inflammatory agents. Although considerable progress has been made in the area of anti-inflammatory treatment, the search for more effective and ... ...

    Abstract Several diterpenoids isolated from terrestrial and marine environments have been identified as important anti-inflammatory agents. Although considerable progress has been made in the area of anti-inflammatory treatment, the search for more effective and safer compounds is a very active field of research. In this study we investigated the anti-inflammatory effects of a known pseudopterane diterpene (referred here as compound 1) isolated from the octocoral Pseudopterogorgia acerosa on the tumor necrosis factor- alpha (TNF-α) and TLRs- induced response in macrophages. Compound 1 inhibited the expression and secretion of the inflammatory mediators TNF-α, interleukin (IL)-6, IL-1β, nitric oxide (NO), interferon gamma-induced protein 10 (IP-10), ciclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and monocyte chemoattractant protein-1 (MCP-1) induced by LPS in primary murine macrophages. This effect was associated with the inhibition of IκBα degradation and subsequent activation of NFκB. Compound 1 also inhibited the expression of the co-stimulatory molecules CD80 and CD86, which is a hallmark of macrophage activation and consequent initiation of an adaptive immune response. The anti-inflammatory effect was not exclusive to LPS because compound 1 also inhibited the response of macrophages to TNF-α and TLR2 and TLR3 ligands. Taken together, these results indicate that compound 1 is an anti-inflammatory molecule, which modulates a variety of processes occurring in macrophage activation.
    Keywords Medicine ; R ; Science ; Q
    Subject code 616 ; 610
    Language English
    Publishing date 2013-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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