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New series of mononuclear β-diketonate cerium(iii) field induced single-molecule magnets
(Royal Society of Chemistry, 2024-05-08) Tubau Ribot, Ànnia; Gómez Coca, Silvia; Speed Castro, Saskia; Font Bardia, Ma. Mercedes; Vicente Castillo, Ramón
Five new β-diketonate Ce3+ mononuclear complexes, [Ce(Btfa)3(H2O)2] (1), [Ce(Btfa)3(phen)] (2), [Ce (Btfa)3(bipy)] (3), [Ce(Btfa)3(terpy)] (4) and [Ce(Btfa)3(bathophen)(DMF)] (5), where Btfa− = 4,4,4-trifluoro-1- phenyl-1,3-butanedionate, phen = 1,10-phenanthroline, bipy = 2,2’-bipyridyl, terpy = 2,2’:6’,2’’-terpyridine and bathophen = 4,7-diphenyl-1,10-phenanthroline, have been synthesized and structurally characterized through X-ray diffraction of single crystals. The central Ce3+ atom displays a coordination number of 8 for 1, 2 and 3 and of 9 for 4 and 5. Under a 0 T external magnetic field, none of the given compounds exhibits single molecule magnet (SMM) behaviour. However, a small magnetic field, between 0.02 and 0.1 T, is enough for all the compounds to exhibit slow relaxation of the magnetization. A comprehensive magnetic analysis, with experimental magnetic data and ab initio calculations, was undertaken for all the complexes, and the study highlights the significance of the different spin relaxation mechanisms that must be considered for a Ce3+ lanthanide ion.
Synthesis of Cyclopalladated Derivatives of (E)-N2 Benzylidene-2-(2,6-dichlorophenyl)ethanamine and Their Reactivity towards Monodentate andSymmetric Bidentate Lewis Bases
(Wiley-VCH, 2011-08) Albert Mach, Joan; Bosque Pueyo, Ramón; D'Andrea Rodríguez-Vida, Lucía; Granell Sanvicente, Jaime Ramón; Calvet Pallàs, Maria Teresa; Font Bardia, Ma. Mercedes
Treatment of the monoimine (E)-N-benzylidene-2-(2,6-dichlorophenyl)ethanamine (1) with a stoichiometric amount of Pd(OAc)(2) in acetic acid at 60 degrees C under nitrogen produced the corresponding acetato-bridged endo five-membered ortho-cyclopalladated dimer [Pd{C(6)H(4)CH=N(CH(2))(2)(2,6-Cl(2)C(6)H(3))}(mu-OAc)](2) (2), which was isolated in pure form in 80% yield. Reaction of 2 with an excess of LiCl in acetone gave rise to the corresponding chlorido-bridged cyclopalladated dimer [Pd{C(6)H(4)CH=N(CH(2))(2)(2,6-Cl(2)C(6)H(3))}(mu-Cl)](2) (3) in 88 % yield. Compounds 2 and 3 reacted with an excess of [D(5)]pyridine or a stoichiometric amount of PPh(3) to give the mononuclear compounds trans-N,L-[Pd{C(6)H(4)CH=N(CH(2))(2)(2,6-Cl(2)C(6)H(3))}(X)(L)] (4: X = OAc, L = [D(5)]py; 5: X = Cl, L = [D(5)]py; 6: X = OAc, L = PPh(3); 7: X = Cl, L = PPh(3)). Compounds 4 and 5 were prepared in a CDCl(3)/[D(5)]py solution and studied by (1)H and (13)C{(1)H) NMR spectroscopy, but they were not isolated. Compound 3 was treated with different types of symmetric bidentate Lewis bases in a 1:1 molar ratio to give high yields of the dinuclear compounds trans-N,L-[(Pd{C(6)H(4)CH=N(CH(2))(2)(2,6-Cl(2)C(6)H(3))}Cl)(2){mu-L(2)}] {8: L(2) = Ph(2)PCH(2)CH(2)PPh(2); 9: L(2) = trans-Ph(2)PCH=CHPPh(2); 10: L(2) = 4,4'-bipyridine; 11: L(2) = NH(2)CH(2)CH(2)OCH(2)CH(2)OCH(2)CH(2)NH(2); 12: L(2) = NH(2)CH(2)(CHOH)CH(2)NH(2))] in which the symmetric bidentate Lewis base bridged two identical cyclopalladated units. Compounds 1-3 and 6-12 were fully characterized by elemental analysis, mass spectrometry, IR and (1)H and (13)C{(1)H} NMR spectroscopy. In addition, the crystal structures of 2, 8 center dot 2CH(2)Cl(2), 10 center dot 4CHCl(3) and 11 center dot 2CH(2)Cl(2) were determined by single-crystal X-ray diffraction analysis. Also reported is the theoretical study of the differences in the absolute Gibbs free energies in acetone or CHCl(3) solution between the cis- and trans-N,L stereoisomers of compounds [Pd(C-N)(X)(L)] in which Pd(C-N) is a model of an endo five-membered ortho-cyclopalladated imine, X is OAc, Cl, Br or I and L is py, NH(3) or PH(3).
Cooperativity effects in a new pterostilbene/phenanthroline cocrystal
(Elsevier B.V., 2023-03-02) Barbas Cañero, Rafael; Bofill, Lídia; Kumar, Vineet; Prohens López, Rafael; Frontera, Antonio
The SCXRD structure of the natural dietary compound pterostilbene (trans-3,5-dimethoxy-4-hydroxystilbene) and phenanthroline (1,10-phenanthroline) cocrystal is reported herein. In the solid state the cocrystal forms several H-bonded and Csingle bondH···π supramolecular synthons that have been analyzed by DFT calculations, with a particular focus on the parallel face-to-face stacking of the phenanthroline rings, a relevant and quite unusual feature (antiparallel displaced mode is more common). Cooperativity effects between H-bonding and aromatic interactions have been studied to rationalize the formation of this unusual π-stacking mode and the supramolecular assemblies have been further analyzed using several computational techniques, i.e., molecular electrostatic potential (MEP) surfaces and the quantum theory of 'atom-in-molecules' (QTAIM) combined with reduced density gradient (RDG) plots.
On the uptake of cationic liposomes by cells: from changes in elasticity to internalization
(Elsevier B.V., 2023-01-01) Botet Carreras, Adrià; Bosch Marimon, Manel; Millán Solsona, Rubén; Aubets Gil, Eva; Ciudad i Gómez, Carlos Julián; Noé Mata, Verónica; Montero, M.Teresa; Domènech Cabrera, Òscar; Borrell Hernández, Jordi
In this study, we assessed the capacity of a previously reported engineered liposomal formulation, which had been tested against model membranes mimicking the lipid composition of the HeLa plasma membrane, to fuse and function as a nanocarrier in cells. We used atomic force microscopy to observe physicochemical changes on the cell surface and confocal microscopy to determine how the liposomes interact with cell membranes and released their load. In addition, we performed viability assays using methotrexate as an active drug to obtain proof of concept of the formulation´s capacity to function as a drug delivery-system. The interaction of engineered liposomes with living cells corroborates the information obtained using model membranes and supports the capacity of the engineered liposomal formulation to serve as a potential nanocarrier.
The Solid State Landscape of the Sildenafil Drug
(Wiley, 2022-04) Barbas Cañero, Rafael; Llinàs, Antonio; Prohens López, Rafael
Sildenafil, the active ingredient of the drug developed by Pfizer for the treatment of erectile dysfunction was firstly synthesized in 1989 in the United Kingdom and since then it has become one of the most prescribed drugs for sexual performance in the western world with more than 2.7 million prescriptions in the US in 2021. Since its discovery, this drug compound has attracted the interest of formulators and crystallographers, with a high number of crystal forms of sildenafil being found and characterized, including polymorphs, hydrates, solvates, salts and cocrystals, converting it in one of the most promiscuous multicomponent crystal former drugs in the pharmaceutical sciences arena. In this minireview, the polymorph, pseudopolymorph and multicomponent solid forms landscape of sildenafil is presented through a comprehensive compilation of their 42 solid forms reported in literature
Revision of the Crystal structure of the orthorhombic polymorph of oxyma: on the importance of π-hole interactions and their interplay with H-bonds
(MDPI, 2022-06-10) Barbas Cañero, Rafael; Sande, Dafne de; Font Bardia, Ma. Mercedes; Prohens López, Rafael; Frontera, Antonio
In this work the crystal structure of the previously described orthorhombic polymorph of the coupling reagent Oxyma has been revised, corrected now as centrosymmetric and analyzed by means of DFT calculations. In the solid state the structure forms a network of H-bonds and self-assembled dimers that are held together by the formation of N···C π-hole interactions involving the C-atom of the imino group. The H-bonding and π-hole interactions observed in the solid state were rationalized using molecular electrostatic potential (MEP) surfaces, focusing on the H-bond donor-acceptor groups and the π-hole observed above and below the molecular plane. The interactions and their interplay have been characterized by using two methodologies based on the topology of the electron density, which are the quantum theory of 'atom-in-molecules' (QTAIM) and the noncovalent interaction plot (NCIplot).
Petrophysical Characterization of Non-Magnetic Granites; Density and Magnetic Susceptibility Relationships
(MDPI, 2022-06-08) Pueyo, Emilio; Román Berdiel, Teresa; Calvín, Pablo; Bouchez, Jean Luc; Beamud Amorós, Elisabet; Ayala, Conxi; Loi, Francesca; Soto Marín, Ruth; Clariana, Pilar; Margalef, Aina; Bach, Nuria; Schamuells, Nia; Rubio, Félix M.; Gimeno, Ana; Fernández de Arévalo, Elena; Rey Moral, Carmen; García, Arturo; Martí, Joan; Casas, Antonio M.; García Lobón, José Luis
In this work we establish reliable correlations between density and magnetic susceptibility in three paramagnetic granites from the Pyrenees. In total, 128 sites (310 density measurements and >2600 susceptibility ones) were studied in the Mont Louis-Andorra, Maladeta and Marimanha granitic plutons covering the main range of variability of magnetic susceptibility. Regressions were calculated for every granitic body and an integrated linear function was obtained for the entire dataset: ρ (kg/m3) = 2566 (kg/m3) + 0.541κ (10−6 S.I.) (R:0.97). This relationship is only valid in the paramagnetic domain, where iron is mostly fractioned in iron-bearing phyllosilicates and the occurrence of magnetite is negligible (or at least its contribution to the bulk susceptibility). This relationship, likely different in other bodies, allows for transforming magnetic susceptibility data into density data, helping to constrain gravity modelling when density data from rock samples are scarce. Given the large amount of AMS studies worldwide, together with the quickness and cost-effectiveness of susceptibility measurements with portable devices, this methodology allows for densifying and homogenizing the petrophysical data when modelling granite rock volumes based on both magnetic and gravimetric signals.
Towards Cellular Ultrastructural Characterization in Organ-on-a-Chip by Transmission Electron Microscopy
(2021-09-30) Glinkowska Mares, Adrianna; Feiner Gracia, Natalia; Muela, Yolanda; Martínez, Gema; Delgado, Lídia; Albertazzi, Lorenzo; Pujals Riatós, Silvia
Organ-on-a-chip technology is a 3D cell culture breakthrough of the last decade. This rapidly developing field of bioengineering intertwined with microfluidics provides new insights into disease development and preclinical drug screening. So far, optical and fluorescence microscopy are the most widely used methods to monitor and extract information from these models. Meanwhile transmission electron microscopy (TEM), despite its wide use for the characterization of nanomaterials and biological samples, remains unexplored in this area. In our work we propose a TEM sample preparation method, that allows to process a microfluidic chip without its prior deconstruction, into TEM-compatible specimens. We demonstrated preparation of tumor blood vessel-on-a-chip model and consecutive steps to preserve the endothelial cells lining microfluidic channel, for the chip’s further transformation into ultrathin sections. This approach allowed us to obtain cross-sections of the microchannel with cells cultured inside, and to observe cell adaptation to the channel geometry, as well as the characteristic for endothelial cells tight junctions. The proposed sample preparation method facilitates the electron microscopy ultrastructural characterization of biological samples cultured in organ-on-a-chip device.
Diverse coordination numbers and geometries in pyridyl adducts of lanthanide(III) complexes based on beta-diketonate
(MDPI, 2021) Mautner, Franz A.; Bierbaumer, Florian; Fischer, Roland C.; Torvisco, Ana; Vicente Castillo, Ramón; Font Bardia, Ma. Mercedes; Tubau Ribot, Ànnia; Speed Castro, Saskia; Massoud, Salah S.
t: Ten mononuclear rare earth complexes of formula [La(btfa)3 (H2O)2 ] (1), [La(btfa)3 (4,40 - Mt2bipy)] (2), [La(btfa)3 (4,40 -Me2bipy)2 ] (3), [La(btfa)3 (5,50 -Me2bipy)2 ] (4), [La(btfa)3 (terpy)] (5), [La(btfa)3 (phen)(EtOH)] (6), [La(btfa)3 (4,40 -Me2bipy)(EtOH)] (7), [La(btfa)3 (2-benzpy)(MeOH)] (8), [Tb(btfa)3 (4,40 -Me2bipy)] (9) and (Hpy)[Eu(btfa)4 ] (10), where btfa = 4,4,4-trifuoro-1-phenylbutane1,3-dionato anion, 4,40 -Mt2bipy = 4,40 -dimethoxy-2,20 -bipyridine, 4,40 -Me2bipy = 4,40 -dimethyl2,20 -bipyridine, 5,50 -Me2bipy = 5,50 -dimethyl-2,20 -bipyridine, terpy = 2,20 :60 ,20 -terpyridine, phen = 1,10-phenathroline, 2-benzpy = 2-(2-pyridyl)benzimidazole, Hpy = pyridiniumH+ cation) have been synthesized and structurally characterized. The complexes display coordination numbers (CN) eight for 1, 2, 9, 10, nine for 5, 6, 7, 8 and ten for 3 and 4. The solid-state luminescence spectra of Tb-9 and Eu-10 complexes showed the same characteristic bands predicted from the Tb(III) and Eu(III) ions. The Overall Quantum Yield measured (φTOT) at the excitation wavelength of 371 nm for both compounds yielded 1.04% for 9 and up to 34.56% for 10 years.
Applicability of magnetic fabrics in rocks associated with the emplacement of salt structures (the Bicorb-Quesa and Navarrés salt walls, Prebetics, SE Spain)
(Elsevier B.V., 2014-07-12) Soto Marín, Ruth; Beamud Amorós, Elisabet; Oliva-Urcia, Belén; Roca i Abella, Eduard; Rubinat Cabanas, Marc; Villaín, Juan J.
This work assesses the applicability of the analysis of the anisotropy of magnetic susceptibility (AMS) to rocks associated with salt structures.Magnetic fabrics from16 sites sampled on Upper Triassic clays (Keuper facies) interbedded within the salt layers of the Bicorb-Quesa and Navarrés saltwalls (Prebetic Zone, SE Spain) aremostly characterized by oblate magnetic ellipsoids with theirmagnetic foliation parallel to the bedding andmagnetic lineation contained in the bedding plane but without a constant relationship with dip direction. To evaluate the quality and significance of the low-field AMS, several experiments were carried out to characterize the magnetic mineralogy of representative samples and enable separation of the contributions from paramagnetic and ferromagnetic (s.l.) minerals. The comparison between the orientation of the observed magnetic lineation and that of the structural elements characterizing the internal geometry of the studied salt structures (antiforms, minor folds, faults and shear zones) and flanks indicates that the magnetic fabric is controlled by deformation processes affecting the salt walls during their growth and/or evolution. Samples were also analyzed from sixteen sites from Miocene rocks outcropping in several syn-diapiric Miocene half-grabens related to the salt walls studied. Their magnetic fabric is interpreted to reflect the dominant stretching direction at the syn-diapiric half grabens during and/or shortly after deposition. Our results indicate that caution is required in interpreting magnetic lineations related to salt flow mechanics from rocks associated with salt structures.
A Novel, Extremely Bioavailable Cocrystal of Pterostilbene
(American Chemical Society, 2021-03-03) Bofill, Lídia; Barbas Cañero, Rafael; Sande, Dafne de; Font Bardia, Ma. Mercedes; Ràfols Llach, Clara; Albertí, Joan; Prohens López, Rafael
New multicomponent solid forms of the nutraceutical pterostilbene have been discovered and characterized through experimental cocrystal screening. Among the coformers tested, picolinic acid formed a cocrystal with a 10-fold enhancement of oral bioavailability in rats, which converts the new cocrystal into a very promising candidate for new formulations of pterostilbene with improved performance.
Extracellular Vesicles Derived from Plasmodium-infected and Non-infected Red Blood Cells as Targeted Drug Delivery Vehicles
(Elsevier, 2020-09-25) Borgheti Cardoso, Livia Neves; Kooijmans, Sander A. A.; Gutiérrez Chamorro, Lucía; Biosca, Arnau; Lantero, Elena; Ramírez, Miriam; Avalos Padilla, Yunuen; Crespo, Isabel; Fernandez Vidal, Irene; Fernández Becerra, Carmen; Portillo Obando, Hernando A. del; Fernàndez Busquets, Xavier
Among several factors behind drug resistance evolution in malaria is the challenge of administering overall doses that are not toxic for the patient but that, locally, are sufficiently high to rapidly kill the parasites. Thus, a crucial antimalarial strategy is the development of drug delivery systems capable of targeting antimalarial compounds to Plasmodium with high specificity. In the present study, extracellular vesicles (EVs) have been evaluated as a drug delivery system for the treatment of malaria. EVs derived from naive red blood cells (RBCs) and from Plasmodium falciparum-infected RBCs (pRBCs) were isolated by ultrafiltration followed by size exclusion chromatography. Lipidomic characterization showed that there were no significant qualitative differences between the lipidomic profiles of pRBC-derived EVs (pRBC-EVs) and RBC-derived EVs (RBC-EVs). Both EVs were taken up by RBCs and pRBCs, although pRBC-EVs were more efficiently internalized than RBC-EVs, which suggested their potential use as drug delivery vehicles for these cells. When loaded into pRBC-EVs, the antimalarial drugs atovaquone and tafenoquine inhibited in vitro P. falciparum growth more efficiently than their free drug counterparts, indicating that pRBC-EVs can potentially increase the efficacy of several small hydrophobic drugs used for the treatment of malaria.
Multi-laboratory experiment PME11 for the standardization of phosphoproteome analysis
(Elsevier BV, 2021-11-01) Colomé, Núria; Abián, Joaquín; Aloria, Kerman; Arizmendi, Jesús M.; Barceló Batllori, Sílvia; Braga Lagache, Sophie; Burlet Schiltz, Odile; Carrascal, Montse; Casal, J. Ignacio; Chicano Gálvez, Eduard; Chiva, Cristina; Clemente, Luis Felipe; Elortza, Felix; Estanyol i Ullate, Josep Maria; Fernandez Irigoyen, Joaquín; Fernández Puente, Patricia; Fidalgo, María José; Froment, Carine; Fuentes, Manuel; Fuentes Almagro, Carlos; Gay, Marina; Hainard, Alexandre; Heller, Manfred; Hernández, María Luisa; Ibarrola, Nieves; Iloro, Ibon; Kieselbach, Thomas; Lario, Antonio; Locard Paulet, Marie; Marina Ramírez, Anabel; Martín, Luna; Morato López, Esperanza; Muñoz, Javier; Navajas, Rosana; Odena, M. Antonia; Odriozola, Leticia; Oliveira, Eliandre; Paradela, Alberto; Pasquarello Mosimann, Carla; Rios, Vivian de los; Ruiz Romero, Cristina; Sabidó Aguadé, Eduard; Sánchez del Pino, Manuel; Sancho, Jaime; Santamaría, Enrique; Schaeffer Reiss, Christine; Schneider, Justine; Torre, Carolina de la; Valero, M. Luz; Vilaseca, Marta; Wu, Shuai; Wu, Linfeng; Ximénez Embún, Pilar; Canals, Francesc; Corrales, Fernando
Global analysis of protein phosphorylation by mass spectrometry proteomic techniques has emerged in the last decades as a powerful tool in biological and biomedical research. However, there are several factors that make the global study of the phosphoproteome more challenging than measuring non-modified proteins. The low stoichiometry of the phosphorylated species and the need to retrieve residue specific information require particular attention on sample preparation, data acquisition and processing to ensure reproducibility, qualitative and quantitative robustness and ample phosphoproteome coverage in phosphoproteomic workflows. Aiming to investigate the effect of different variables in the performance of proteome wide phosphoprotein analysis protocols, ProteoRed-ISCIII and EuPA launched the Proteomics Multicentric Experiment 11 (PME11). A reference sample consisting of a yeast protein extract spiked in with different amounts of a phosphomix standard (Sigma/Merck) was distributed to 31 laboratories around the globe. Thirty-six datasets from 23 laboratories were analyzed. Our results indicate the suitability of the PME11 reference sample to benchmark and optimize phosphoproteomics strategies, weighing the influence of different factors, as well as to rank intra and inter laboratory performance.
Maternal proteomic profiling reveals alterations in lipid metabolism in late-onset fetal growth restriction
(Nature Publishing Group, 2020-12-03) Paules, Cristina; Youssef, Lina; Miranda, Jezid; Crovetto, Francesca; Estanyol i Ullate, Josep Maria; Fernàndez, Guerau; Crispi Brillas, Fàtima; Gratacós Solsona, Eduard
Fetal growth restriction defined as the failure to achieve the fetal genetic growth potential is a major cause of perinatal morbidity and mortality. The role of maternal adaptations to placental insufficiency in this disorder is still not fully understood. We aimed to investigate the biological processes and protein-protein interactions involved in late-onset fetal growth restriction in particular. We applied 2D nano LC-MS/MS proteomics analysis on maternal blood samples collected at the time of delivery from 5 singleton pregnancies with late-onset fetal growth restriction and 5 uncomplicated pregnancies. Data were analyzed using R package 'limma' and Ingenuity Pathway Analysis. 25 proteins showed significant changes in their relative abundance in late-onset fetal growth restriction (p value < 0.05). Direct protein-protein interactions network demonstrated that Neurogenic locus notch homolog protein 1 (NOTCH1) was the most significant putative upstream regulator of the observed profile. Gene ontology analysis of these proteins revealed the involvement of 14 canonical pathways. The most significant biological processes were efflux of cholesterol, efflux of phospholipids, adhesion of blood cells, fatty acid metabolism and dyslipidemia. Future studies are warranted to validate the potential role of the detected altered proteins as potential therapeutic targets in the late-onset form of fetal growth restriction.
Mapping the magnetic coupling of self-assembled Fe3O4 nanocubes by electron holography
(MDPI, 2021-02-06) López Conesa, Lluís; Martínez Boubeta, Carlos; Serantes, David; Estradé Albiol, Sònia; Peiró Martínez, Francisca
The nanoscale magnetic configuration of self-assembled groups of magnetite 40 nm cubic nanoparticles has been investigated by means of electron holography in the transmission electron microscope (TEM). The arrangement of the cubes in the form of chains driven by the alignment of their dipoles of single nanocubes is assessed by the measured in-plane magnetic induction maps, in good agreement with theoretical calculations.
Probing the Kinetic and Thermodynamic Fingerprints of Anti-EGF Nanobodies by Surface Plasmon Resonance
(MDPI, 2020-06-26) Guardiola Bagán, Salvador; Varese, Monica; Taulés i Marín, Marta; Díaz Lobo, Mireia; García Arroyo, Jesús; Giralt Lledó, Ernest
Despite the widespread use of antibodies in clinical applications, the precise molecular mechanisms underlying antibody-antigen (Ab-Ag) interactions are often poorly understood. In this study, we exploit the technical features of a typical surface plasmon resonance (SPR) biosensor to dissect the kinetic and thermodynamic components that govern the binding of single-domain Ab or nanobodies to their target antigen, epidermal growth factor (EGF), a key oncogenic protein that is involved in tumour progression. By carefully tuning the experimental conditions and transforming the kinetic data into equilibrium constants, we reveal the complete picture of binding thermodynamics, including the energetics of the complex-formation transition state. This approach, performed using an experimentally simple and high-throughput setup, is expected to facilitate mechanistic studies of Ab-based therapies and, importantly, promote the rational development of new biological drugs with suitable properties.
Construction of Zn(II) Linear Trinuclear Secondary Building Units from A Coordination Polymer Based on α-Acetamidocinnamic Acid and 4-Phenylpyridine
(MDPI, 2020-08-09) Ejarque, Daniel; Calvet Pallàs, Maria Teresa; Font Bardia, Ma. Mercedes; Pons, Josefina
The synthesis and characterization of one coordination polymer and two trinuclear complexes are presented. The coordination polymer [Zn2( -O,O'-ACA)2(ACA)2(4-Phpy)2]n (1) has been obtained by the reaction between Zn(OAc)2 2H2O, -acetamidocinnamic acid (HACA), and 4-phenylpyridine (4-Phpy) using EtOH as solvent. Its recrystallization in CH3CN or EtOH yields two trinuclear complexes, both having pinwheel arrays with formulas [Zn3( -ACA)6(4-Phpy)2] 4CH3CN (2 4CH3CN) and [Zn3( -ACA)6(EtOH)2] 4EtOH (3 4EtOH), respectively. These trinuclear species, unavoidably lose their solvent co-crystallized molecules at RT yielding the complexes [Zn3( -ACA)6(4-Phpy)2] (2) and [Zn3( -ACA)6(EtOH)2] (3). In addition, compound 2 has also been obtained reacting Zn(OAc)2 2H2O, HACA, and 4-Phpy in a 1:2:2 ratio using CH3CN as solvent. Compounds 1-3 have been characterized by analytical and spectroscopic techniques. Furthermore, single crystals suitable for X-ray di raction method for compounds 1, 2 4CH3CN, and 3 4EtOH were obtained and their supramolecular interactions have been studied and discussed, showing 2D supramolecular planes for the trinuclear complexes and a 3D supramolecular network for the coordination polymer. Finally, the supramolecular interactions of 2 4CH3CN and 3 4EtOH have been compared using Hirshfeld surface analysis and electrostatic potential calculations.
GCAP neuronal calcium sensor proteins mediate photoreceptor cell death in the rd3 mouse model of LCA12 congenital blindness by involving endoplasmic reticulum stress
(Nature Publishing Group, 2020-01-24) Plana-Bonamaisó, Anna; López Begines, Santiago; Andilla, Jordi; Fidalgo, María José; Loza Álvarez, Pablo; Estanyol i Ullate, Josep Maria; Villa, Pedro de la; Méndez Zunzunegui, Ana
Loss-of-function mutations in the retinal degeneration 3 (RD3) gene cause inherited retinopathy with impaired rod and cone function and fast retinal degeneration in patients and in the natural strain of rd3 mice. The underlying physiopathology mechanisms are not well understood. We previously proposed that guanylate cyclase-activating proteins (GCAPs) might be key Ca2+-sensors mediating the physiopathology of this disorder, based on the demonstrated toxicity of GCAP2 when blocked in its Ca2+-free form at photoreceptor inner segments. We here show that the retinal degeneration in rd3 mice is substantially delayed by GCAPs ablation. While the number of retinal photoreceptor cells is halved in 6 weeks in rd3 mice, it takes 8 months to halve in rd3/rd3 GCAPs−/− mice. Although this substantial morphological rescue does not correlate with recovery of visual function due to very diminished guanylate cyclase activity in rd3 mice, it is very informative of the mechanisms underlying photoreceptor cell death. By showing that GCAP2 is mostly in its Ca2+-free-phosphorylated state in rd3 mice, we infer that the [Ca2+]i at rod inner segments is permanently low. GCAPs are therefore retained at the inner segment in their Ca2+-free, guanylate cyclase activator state. We show that in this conformational state GCAPs induce endoplasmic reticulum (ER) stress, mitochondrial swelling, and cell death. ER stress and mitochondrial swelling are early hallmarks of rd3 retinas preceding photoreceptor cell death, that are substantially rescued by GCAPs ablation. By revealing the involvement of GCAPs-induced ER stress in the physiopathology of Leber's congenital amaurosis 12 (LCA12), this work will aid to guide novel therapies to preserve retinal integrity in LCA12 patients to expand the window for gene therapy intervention to restore vision.
Preparation and characterization of a supramolecular hydrogel made of phospholipids and oleic acid with a high water content
(Royal Society of Chemistry, 2019-11-13) Talló, Kirian; Bosch Marimon, Manel; Pons, Ramon; Cocera, Mercedes; López, Olga
A hydrogel formed with phospholipids and fatty acids would be of great interest in the medical field due to the biological relevance that these molecules have in living organisms. However, the tendency of phospholipid mixtures to form vesicular or micellar aggregates at high water content hinders the formation of this type of hydrogel. In this study, a highly hydrated hydrogel (95% water) was formed with hydrogenated phosphatidylcholine and oleic acid. The preparation method involved a freeze-heating cycle of the aqueous lipid mixture, favouring the supramolecular aggregation of these molecules into a microscopic spongy morphology. Confocal fluorescence imaging showed that the microstructure of the hydrogel is made from the aggregation of giant multilamellar vesicles (5-20 μm diameter) while transmission electron microscopy revealed the existence of nanosized unilamellar vesicles (150 nm diameter) coexisting with lipid lamellae. Despite this type of aggregation, X-ray scattering experiments performed on the hydrogel show almost no correlation between lipid membranes. In terms of rheological properties, the material shows a prevalent elastic behaviour and low structural strength, a consequence of non-covalent interactions. With such properties and composition, this structured but easily deformable material might become a useful tool for biomedical applications.
Liquid chromatography-tandem mass spectrometry analysis of eicosanoids and related compounds in cell models
(Elsevier B.V., 2014-05-24) Martín Venegas, Raquel; Jáuregui Pallarés, Olga; Moreno Aznárez, Juan José
Enzyme- and free radical-catalyzed oxidation of polyunsaturated fatty acids (PUFAs) produces the eicosanoids, docosanoids and octadecanoids. This large family of potent bioactive lipids is involved in many biochemical and signaling pathways which are implicated in physiological and pathophysiological processes and can be viable therapeutic targets. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers selectivity, sensitivity, robustness and high resolution and is able to analyze a large number of eicosanoids in biological samples in a short time. The present article reviews and discusses reported LC-MS/MS methods and the results obtained from their application in cell models. Reliable analytical outcomes are critically important for understanding physiological and pathophysiological cellular processes, such as inflammation, diseases with inflammatory components (e.g., cardiovascular disease, diabetes, metabolic syndrome), as well as cancer. Reported findings obtained by using the LC-MS/MS methodology in cell systems may have important predictive as well as nutritional and pharmacological implications. We conclude that the LC-MS/MS methodology is a versatile and reliable analytical tool for the simultaneous analysis of multiple PUFA-derived metabolites including the eicosanoids in cell culture samples at concentrations on the pM/nM threshold, i.e. at baseline and after stimulation.

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