Adequacy and quality of abdominal echographies requested by primary care professionals

<p>Abstract</p> <p>Background</p> <p>The value of abdominal echography in primary care is great because it is innocuous, inexpensive, easy to perform and provides a great deal of information making this the first examination to be requested in cases of probable abdominal disease. <b>However, too many abdominal echographies are probably requested overcrowding the Departments of Radiodiagnosis with not always justified petitions or with repetition of tests based on little clinical criteria</b>.</p> <p>Methods/Design</p> <p><b>The aim of the study is </b>to evaluate the adequacy and quality of abdominal echographies requested by primary care physicians in the Maresme County (North of Barcelona), develop guidelines for indicating echographies and reevaluate this adequacy after implementing these guidelines.</p> <p>We will perform a two-phase study: the first descriptive, and retrospective evaluating the adequacy and quality of petitions for abdominal echographies, and in the second phase we will evaluate the impact of recommendations for indicating abdominal echographies for PC physicians on the adequacy and quality of echography petitions thereafter.</p> <p><b>This study will be carried out in 10 primary care centres </b>in the Maresme (Barcelona).</p> <p>1067 abdominal echographies requested by primary care physicians from the above mentioned centres from January 2007 to April 2010 and referred to the Department of Radiology and the same number of applications after the intervention.</p> <p>All the petitions for abdominal echographies requested will be analysed and the clinical histories will be obtained to determine demographic variables, the reason for the visit and for the echography petition and diagnostic orientation, clinical and echographic data, evaluation of the echographies according to the quality and variables characterising the professionals requesting the echographies including: age, sex, laboral situation, length of time in work post, formation, etc.</p> <p>To achieve a consensus of the adequacy of abdominal echography, a work group including gastroenterologists, radiologists and general practitioners will be created following the nominal group. This will allow the design of guidelines for the indication of abdominal echography and posterior evaluation of their impact among physicians by diffusion and posterior reevaluation of the adequacy of the petitions.</p

Conformation and chiral effects in α,β,α-tripeptides

Short α,β,α-tripeptides comprising a central chiral trisubstituted β 2,2,3*-amino acid residue form unusual γ-turns and δ-turns in CDCl 3 and DMSO-d 6 solutions but do not form β-turns. Thermal coefficients of backbone amide protons, 2D-NMR spectra, and molecular modeling revealed that these motifs were strongly dependent on the configuration (chiral effect) of the central β-amino acid residue within the triad. Accordingly, SSS tripeptides adopted an intraresidual γ-turn like (C6) arrangement in the central β-amino acid, whereas SRS diastereomers preferred an extended δ-turn (C9) conformation. A different SRS-stabilizing bias was observed in the crystal structures of the same compounds, which shared the extended δ-turn (C9) found in solution, but incorporated an additional extended β-turn (C11) to form an overlapped double turn motif.We thank the Gobierno Vasco (Project SAIOTEK S-PR10BF02) and Ministerio de Ciencia e Innovación (Project CTQ2009-07109) for financial support and SGIker UPV/EHU for NMR facilities. C.J.S. thanks Gobierno de Canarias for a predoctoral fellowship

RGD-Functionalized Fe3O4 nanoparticles for magnetic hyperthermia

To improve the selectivity of magnetic nanoparticles for tumor treatment by hyperthermia, Fe3O4 nanoparticles have been functionalized with a peptide of the type arginine-glycine-aspartate (RGD) following a "click" chemistry approach. The RGD peptide was linked onto the previously coated nanoparticles in order to target αvβ3 integrin receptors over-expressed in angiogenic cancer cells. Different coatings have been analyzed to enhance the biocompatibility of magnetic nanoparticles. Monodispersed and homogeneous magnetite nanoparticles have been synthesized by the seed growth method and have been characterized using X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, transmission electron microscopy and magnetic measurements. The magnetic hyperthermia efficiency of the nanoparticles has also been investigated and cytotoxicity assays have been perfomed for functionalized nanoparticles.This work was supported by institutional funding from the Ministry of Economy Industry and Competitiveness and Basque Government under Projects MAT2016-78266-P, FEDER, GIC-IT-570-13, Fondo Social de la DGA (grupos DGA), SAF2014-54763-C2-2-R. Technical and human support provided by SGIker (UPV/EHU) is also gratefully acknowledged. A grant from Gobierno Vasco to M.S.-A. (POS_2015_2-0048) is acknowledged.Peer reviewe

Clickable magnetic nanoparticles - a new tool for magnetic hyperthermia

Resumen del trabajo presentado a la 12th International Conference on the Scientific and Clinical Applications of Magnetic Carriers, celebrada en Copenhague (Dinamarca) del 22 al 26 de mayo de 2018.Magnetic hyperthermia (MH), based on the ability of magnetic nanoparticles (MNPs) to generate heat when exposed to alternating magnetic fields (AMF) is a very active area of research, especially for the development of new therapeutic solutions for cancer treatment. Recently, our team has initiated a new research line focused on the use of bioorthogonal click chemistry for magnetic hyperthermia studies applied using MNPs covalently attached to cell membranes. Our interest lies in the sub-lethal version of MH, which we believe is a powerful tool to induce a controlled and localized heating of the cell membrane (“hotspots”). This could produce temporal changes in the membrane biophysical properties, which can be used for enhanced delivery of therapeutics. Bioorthogonal strain-promoted “click” [3 + 2] azide-alkyne cycloaddition (SPAAC) reaction uses the ring strain to activate the alkyne, thus avoiding the use of the cytotoxic Cu(I) catalyst typically employed for standard “click” azide-alkyne cycloadditions (CuAAC). Despite its numerous applications in biology and biochemistry, SPAAC is still relatively new for nanotechnology applications. Herein, we report a simple functionalization protocol to obtain water-soluble MNPs suitable for SPAAC click chemistry. Hydrophobic 12 nm iron oxide MNPs were synthesized following a seed-mediated thermal decomposition methodology and transferred to water by coating with a fluorescent amphiphilic polymer (poly(maleic anhydride-alt-1- octadecene), PMAO-TAMRA).5 The MNPs were further functionalized step-wise with polyethyleneglycol (PEG) or a glucopyranoside derivative (Glc) to increase colloidal stability and with a cyclooctynylamine derivative. We have tested their reactivity towards azide-functionalized surfaces, demonstrating their potential as bioorthogonal probes. We are currently working on the incorporation of the “clickable” MNPs on more complex substrates (azide-modified lipid bilayers as simplified models of animal cell membranes). Studies regarding the cytotoxicity of the MNPs and their covalent attachment on living cell membranes are also underway.R. M. F. acknowledges financial support from Universidad de Zaragoza (JIUZ-2014-CIE-03), European Union (Marie Sklodowska-Curie grant agreement No. 657215) and MINECO (Ramón y Cajal grant RYC-2015-17640).Peer Reviewe

From bench to cell: A roadmap for assessing the bioorthogonal "click" reactivity of magnetic nanoparticles for cell surface engineering

In this work, we report the use of bioorthogonal chemistry, specifically the strain-promoted click azide–alkyne cycloaddition (SPAAC) for the covalent attachment of magnetic nanoparticles (MNPs) on living cell membranes. Four types of MNPs were prepared, functionalized with two different stabilizing/passivation agents (a polyethylene glycol derivative and a glucopyranoside derivative, respectively) and two types of strained alkynes with different reactivities: a cyclooctyne (CO) derivative and a dibenzocyclooctyne (DBCO) derivative. The MNPs were extensively characterized in terms of physicochemical characteristics, colloidal stability, and click reactivity in suspension. Then, the reactivity of the MNPs toward azide-modified surfaces was evaluated as a closer approach to their final application in a living cell scenario. Finally, the DBCO-modified MNPs, showing superior reactivity in suspension and on surfaces, were selected for cell membrane immobilization via the SPAAC reaction on the membranes of cells engineered to express azide artificial reporters. Overall, our work provides useful insights into the appropriate surface engineering of nanoparticles to ensure a high performance in terms of bioorthogonal reactivity for biological applications.This work has been supported by the European Commission, MagicCellGene Project (M-ERA.NET COFUND call 2016, funded by Ministerio de Economía y Competitividad, MINECO, Spain in the framework of the PCIN-2017-060 project), Ministerio de Innovación, Ciencia y Universidades (MCIU, PGC2018-096016-B-I00 to R.M.F), Ministerio de Economía, Industria y Competitividad (BIO 2017-84246-C2-1R to V.G. and J.M.F.), and MINECO and FSE/Agencia Estatal de Investigación (Ramón y Cajal subprogram, grant RYC-2015-17640 to R.M.F.). J.I.L. and E.M.A acknowledge financial support for their predoctoral fellowships from Gobierno de Aragón (DGA 2017–2021 call, co-funded by the Programa Operativo Fondo Social Europeo de Aragón 2014–2020) and Ministerio de Universidades (FPU17/02024), respectively. Authors also acknowledge support from Gobierno de Aragón and Fondos Feder for funding the Bionanosurf (E15_20R) research group. J.M.A. and M.E. acknowledge support from the Basque Government (GIC-2015_IT-1033-16).Peer reviewe

Covalent immobilisation of magnetic nanoparticles on surfaces via strain-promoted azide–alkyne click chemistry

Herein we report the synthesis of “clickable” magnetic nanoparticles (MNPs) stable in suspension in physiological media for bioorthogonal click chemistry applications. These MNPs incorporate into their coating a cyclooctynyl derivative for strain-promoted azide–alkyne (SPAAC) cycloaddition and either a polyethylene glycol or a glucose moiety to ensure MNP stability in physiological media. Their reactivity towards azide-functionalised Si surfaces was investigated, demonstrating their potential as bioorthogonal probes.This work was supported by Fondo Social Europeo de la DGA (grupos DGA), Ministerio de la Economía y Competitividad del Gobierno de España for the public funding of Proyectos I + D + I – Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad (project no. SAF2014-54763-C2-2-R) and Gobierno Vasco (project IT-1033-16). R. M. F. also acknowledges financial support from Universidad de Zaragoza (JIUZ-2014-CIE-03) and European Union (Marie Skłodowska-Curie grant agreement no. 657215 OUTstandINg).Peer reviewe

"Click" saccharide/beta-lactam hybrids for lectin inhibition

4 páginas, 3 figuras, 2 tablas, 3 esquemas -- PAGS nros. 2227-2230Hybrid glycopeptide beta-lactam mimetics designed to bind lectins or carbohydrate recognition domains in selectins have been prepared according to a "shape-modulating linker" design. This approach was implemented using the azide-alkyne "click" cycloaddition reaction, and as shown by NMR/MD experiments, binding of the resulting mimetics to Ulex Europaeus Lectin-1 (UEL-1) occurred after a "bent-to-extended" conformational change around a partially rotatable triazolylmethylene moietyWe thank the Ministerio de Educación y Ciencia (MEC, Spain) (Projects: CTQ2006-13891/BQU and CTQ10874-C02-01), UPV/EHU, and Gobierno Vasco (ETORTEK-BiomaGUNE IE-05/143) for financial support and SGIker UPV/EHU for NMR facilities. A grant from Gobierno Vasco to I.A. is acknowledgedPeer reviewe