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1.
Analyst ; 146(12): 3750-3776, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34060546

RESUMEN

The ongoing COVID-19 pandemic has shown the importance of having analytical devices that allow a simple, fast, and robust detection of pathogens which cause epidemics and pandemics. The information these devices can collect is crucial for health authorities to make effective decisions to contain the disease's advance. The World Health Organization published a list of primary pathogens that have raised concern as potential causes of future pandemics. Unfortunately, there are no rapid diagnostic tests commercially available and approved by the regulatory bodies to detect most of the pathogens listed by the WHO. This report describes these pathogens, the available detection methods, and highlights areas where more attention is needed to produce rapid diagnostic tests for future pandemic surveillance.


Asunto(s)
COVID-19 , Pandemias , Pruebas Diagnósticas de Rutina , Humanos , SARS-CoV-2
2.
Inorg Chem ; 59(24): 18287-18294, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33289542

RESUMEN

The NiII literature complex cis-[Ni(C6F5)2(THF)2] is a synthon of cis-Ni(C6F5)2 that allows us to establish a protocol to measure and compare the ligand effect on the NiII → Ni0 reductive elimination step (coupling), often critical in catalytic processes. Several ligands of different types were submitted to this Ni-meter comparison: bipyridines, chelating diphosphines, monodentate phosphines, PR2(biaryl) phosphines, and PEWO ligands (phosphines with one potentially chelate electron-withdrawing olefin). Extremely different C6F5-C6F5 coupling rates, ranging from totally inactive (producing stable complexes at room temperature) to those inducing almost instantaneous coupling at 25 °C, were found for the different ligands tested. The PR2(biaryl) ligands, very efficient for coupling in Pd, are slow and inefficient in Ni, and the reason for this difference is examined. In contrast, PEWO type ligands are amazingly efficient and provide the lowest coupling barriers ever observed for NiII complexes; they yield up to 96% C6F5-C6F5 coupling in 5 min at 25 °C (the rest is C6F5H) and 100% coupling with no hydrolysis in 8 h at -22 to -53 °C.

3.
Inorg Chem ; 59(22): 16599-16610, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-33119278

RESUMEN

Six fluorinated PR2(biaryl) phosphines, Ln, with R = Ph, Cy and biaryl = C6H4-C6F5, C6F4-C6H5, C6F4-C6F5, have been prepared. Their [AuCl(Ln)] complexes and H congeners with PhJohnPhos or CyJohnPhos have been studied in order to examine the interactions that bring the distal aryl close to the Au-Cl bond region. X-ray, DFT structure optimization, QTAIM, and NCI methods allow for some understanding of the forces involved. The "no bond" noncovalent distal-aryl/Au-Cl weak interactions are produced at forced short distances achieved under intramolecular structural ligand pressure. Enhanced vdW distal-aryl/Au interactions at "no bond" distances shorter than the sum of Au and C vdW radii and weaker distal-aryl/Cl interactions at "no bond" distances beyond the sum of Cl and C vdW radii counterbalance the unfavorable structural distortion of the free ligand, providing some extra stability of the molecule on the order of 2-10 kcal mol-1. The F substituents in the distal aryl induce shorter aryl distances to the Au-Cl zone, pointing overall to stronger π-aryl polarization as being mainly responsible for the NCIs with gold. The interactions in the C···Cl zone, where the distances are larger than the sum of vdW radii, contribute only about 5%, according to energy estimations using NBOs.

4.
J Sports Sci ; 37(23): 2660-2666, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31448693

RESUMEN

This study identified clusters of adolescents who share similar cardiorespiratory fitness levels and analysed the relationships between cardiorespiratory fitness, inhibition, and math fluency in each of the clusters. The subjects were 490 high-school students aged 10-16 years. The mean age was 13.82 years (SD = 1.12). Latent class analysis identified three clusters with high, medium, and low levels of cardiorespiratory fitness. The high-fitness cluster achieved higher scores in inhibition and math fluency than the low-fitness cluster. Path analysis revealed that the influence of cardiorespiratory fitness on inhibition was non-existent in the three clusters. The effect of inhibition on math fluency was positive and significant in all three cardiorespiratory fitness levels. Cardiorespiratory fitness had a direct, positive, and significant effect on math fluency only in the high-fitness cluster. Therefore, a high level of cardiorespiratory fitness is a significant determining factor in the explanation of math fluency. These results indicate that inhibition does not mediate the relationship between cardiorespiratory fitness and math fluency. However, the benefits of cardiorespiratory fitness affect math fluency, which has important implications for the educational environment and the teaching/learning process.


Asunto(s)
Logro , Capacidad Cardiovascular/fisiología , Capacidad Cardiovascular/psicología , Inhibición Psicológica , Matemática , Adolescente , Niño , Análisis por Conglomerados , Estudios Transversales , Femenino , Humanos , Masculino , Estudiantes/psicología
5.
J Obstet Gynaecol ; 38(1): 55-59, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28782423

RESUMEN

The purpose of this study was to assess the prevalence of postpartum anaemia and determine the clinical risk factors for this condition to provide a viable alternative to postpartum haemoglobin measurement. In total, 1415 patients at Hospital Universitario del Tajo, Madrid, who underwent postpartum haemoglobin testing were included, and risk factors for having an Hb level <10 g/dl were determined. We found that 29% of the mothers were anaemic, and birth canal lacerations, caesarean delivery, episiotomy and South American origin were identified as the main risk factors for this condition. When we examined the performance of each risk factor alone in the prediction of postpartum anaemia, none of them achieved a sensitivity of 30%. Selective screening of women who had any of these five risk factors resulted in 23% of cases remaining unidentified. Despite the high incidence and disease burden of this condition, the management of puerperal anaemia is not standardised, and this condition is not easy to predict. Universal screening should be considered in high-prevalence settings. Impact statement The World Health Organisation (WHO) describes the postnatal period as the most critical and yet most neglected phase in the lives of mothers and infants. It is a common knowledge that a woman's adjustment to life with her new infant is very difficult. This period, known as the puerperium, often involves poor sleep quality, pain and fatigue, if not other major complications. In this context, we must face the challenge of increasing breastfeeding rates, which is why health care providers should be aware of the medical and psychological needs of the new mother. This work reports that postpartum anaemia, a potentially preventable or treatable condition that can make it more difficult to resume everyday activities, is highly prevalent. It remains to be seen whether ensuring the appropriate diagnosis and treatment of anaemia after delivery will result in improvements in the physical and psychological well-being of obstetric patients.


Asunto(s)
Anemia/etiología , Parto Obstétrico/efectos adversos , Complicaciones Hematológicas del Embarazo/etiología , Trastornos Puerperales/etiología , Adulto , Anemia/epidemiología , Parto Obstétrico/métodos , Femenino , Humanos , Incidencia , Embarazo , Complicaciones Hematológicas del Embarazo/epidemiología , Prevalencia , Trastornos Puerperales/epidemiología , Estudios Retrospectivos , Factores de Riesgo , España/epidemiología
6.
Adv Exp Med Biol ; 949: 109-145, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27714687

RESUMEN

Astrocytes perform various homeostatic functions in the nervous system beyond that of a supportive or metabolic role for neurons. A growing body of evidence indicates that astrocytes are crucial for central respiratory chemoreception. This review presents a classical overview of respiratory central chemoreception and the new evidence for astrocytes as brainstem sensors in the respiratory response to hypercapnia. We review properties of astrocytes for chemosensory function and for modulation of the respiratory network. We propose that astrocytes not only mediate between CO2/H+ levels and motor responses, but they also allow for two emergent functions: (1) Amplifying the responses of intrinsic chemosensitive neurons through feedforward signaling via gliotransmitters and; (2) Recruiting non-intrinsically chemosensitive cells thanks to volume spreading of signals (calcium waves and gliotransmitters) to regions distant from the CO2/H+ sensitive domains. Thus, astrocytes may both increase the intensity of the neuron responses at the chemosensitive sites and recruit of a greater number of respiratory neurons to participate in the response to hypercapnia.


Asunto(s)
Astrocitos/fisiología , Dióxido de Carbono/metabolismo , Células Quimiorreceptoras/fisiología , Hipercapnia/metabolismo , Neuronas/fisiología , Centro Respiratorio/fisiología , Aminoácidos/metabolismo , Animales , Astrocitos/citología , Señalización del Calcio , Células Quimiorreceptoras/citología , Humanos , Hipercapnia/fisiopatología , Locus Coeruleus/citología , Locus Coeruleus/fisiología , Núcleos del Rafe Mesencefálico/citología , Núcleos del Rafe Mesencefálico/fisiología , Neuronas/citología , Neurotransmisores/metabolismo , Protones , Centro Respiratorio/citología , Serotonina/metabolismo , Transmisión Sináptica
7.
Adv Exp Med Biol ; 949: 1-24, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27714682

RESUMEN

Today, there is enormous progress in understanding the function of glial cells, including astroglia, oligodendroglia, Schwann cells, and microglia. Around 150 years ago, glia were viewed as a glue among neurons. During the course of the twentieth century, microglia were discovered and neuroscientists' views evolved toward considering glia only as auxiliary cells of neurons. However, over the last two to three decades, glial cells' importance has been reconsidered because of the evidence on their involvement in defining central nervous system architecture, brain metabolism, the survival of neurons, development and modulation of synaptic transmission, propagation of nerve impulses, and many other physiological functions. Furthermore, increasing evidence shows that glia are involved in the mechanisms of a broad spectrum of pathologies of the nervous system, including some psychiatric diseases, epilepsy, and neurodegenerative diseases to mention a few. It appears safe to say that no neurological disease can be understood without considering neuron-glia crosstalk. Thus, this book aims to show different roles played by glia in the healthy and diseased nervous system, highlighting some of their properties while considering that the various glial cell types are essential components not only for cell function and integration among neurons, but also for the emergence of important brain homeostasis.


Asunto(s)
Astrocitos/fisiología , Microglía/fisiología , Fenómenos Fisiológicos del Sistema Nervioso , Neuronas/fisiología , Oligodendroglía/fisiología , Células de Schwann/fisiología , Astrocitos/citología , Epilepsia/patología , Epilepsia/fisiopatología , Humanos , Microglía/citología , Esclerosis Múltiple/patología , Esclerosis Múltiple/fisiopatología , Sistema Nervioso/patología , Sistema Nervioso/fisiopatología , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/fisiopatología , Neuronas/citología , Óxido Nítrico/fisiología , Oligodendroglía/citología , Estrés Oxidativo , Células de Schwann/citología , Sinapsis/fisiología , Transmisión Sináptica/fisiología
8.
Electrophoresis ; 34(7): 1105-12, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23436323

RESUMEN

Protein nanofibrils and nanotubes are now widely accepted as having potential for use in the field of bionanotechnology. For this to be a feasible alternative to existing technologies, there is a need for a commercially viable source. Previous work has identified amyloid fibrils formed from crude crystallin proteins as such a source, since these fibrils can be produced in large quantities at a low cost. Applications include use of fibrils as templates for the formation of nanowires or as biosensing scaffolds. There remains a number of practical considerations, such as stability and the ability to control their arrangement. In this study, crude crystallin amyloid fibrils are shown to be stable in a range of biological and clean room solvents, with the fibril presence confirmed by transmission electron microscopy and the thioflavin T fluorescent assay. The fibrils were also immobilised between microelectrodes using dielectrophoresis, which enabled the recording of I-V curves for small numbers of fibrils. This investigation showed the fibrils to have low conductivity, with current values in the range of 10(-10) A recorded. This low conductivity could be increased through modification, or alternately, the fibrils could be used unmodified for applications where they can act as templates or high surface area nanoscaffolds.


Asunto(s)
Amiloide/química , Cristalinas/química , Electroforesis/métodos , Nanoestructuras/química , Amiloide/metabolismo , Animales , Cristalinas/metabolismo , Conductividad Eléctrica , Gadiformes , Cristalino/química , Microscopía Electrónica de Transmisión , Estabilidad Proteica , Solubilidad
9.
Analyst ; 138(4): 1026-31, 2013 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-23150875

RESUMEN

This article describes the preparation of a graphene electrode modified with a new conjugate of peptide nanotubes and folic acid for the selective detection of human cervical cancer cells over-expressing folate receptors. The functionalization of peptide nanotubes with folic acid was confirmed by fluorescence microscopy and atomic force microscopy. The peptide nanotube-folic acid modified graphene electrode was characterized by scanning electron microscopy and cyclic voltammetry. The modification of the graphene electrode with peptide nanotube-folic acid led to an increase in the current signal. The human cervical cancer cells were bound to the modified electrode through the folic acid-folate receptor interaction. Cyclic voltammograms in the presence of [Fe(CN)(6)](3-/4-) as a redox species demonstrated that the binding of the folate receptor from human cervical cancer cells to the peptide nanotube-folic acid modified electrode lowered the electron transfer resulting in a decrease in the measured current. A detection limit of 250 human cervical cancer cells per mL was obtained. Control experiments confirmed that the peptide nanotube-folic acid electrode specifically recognized folate receptors. The modified electrode described here opens up new possibilities for future applications in early stage diagnoses of diseases where cells over-express folate receptors, such as in cancer or leishmaniasis disease.


Asunto(s)
Ácido Fólico/química , Grafito/química , Nanotubos de Péptidos/química , Neoplasias del Cuello Uterino/química , Electrodos , Femenino , Células HeLa , Humanos , Neoplasias del Cuello Uterino/diagnóstico
10.
Analyst ; 138(13): 3651-9, 2013 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-23628978

RESUMEN

A surface modification of interdigitated gold microelectrodes (IDEs) with a doped polypyrrole (PPy) film for detection of dopamine released from populations of differentiated PC12 cells is presented. A thin PPy layer was potentiostatically electropolymerized from an aqueous pyrrole solution onto electrode surfaces. The conducting polymer film was doped during electropolymerization by introducing counter-ions in the monomer solution. Several counter-ions were tested and the resulting electrode modifications were characterized electrochemically to find the optimal dopant that increases sensitivity in dopamine detection. Overoxidation of the PPy films was shown to contribute to a significant enhancement in sensitivity to dopamine. The changes caused by overoxidation in the electrochemical behavior and electrode morphology were investigated using cyclic voltammetry and SEM as well as AFM, respectively. The optimal dopant for dopamine detection was found to be polystyrene sulfonate anion (PSS(-)). Rat pheochromocytoma (PC12) cells, a suitable model to study exocytotic dopamine release, were differentiated on IDEs functionalized with an overoxidized PSS(-)-doped PPy film. The modified electrodes were used to amperometrically detect dopamine released by populations of cells upon triggering cellular exocytosis with an elevated K(+) concentration. A comparison between the generated current on bare gold electrodes and gold electrodes modified with overoxidized doped PPy illustrates the clear advantage of the modification, yielding 2.6-fold signal amplification. The results also illustrate how to use cell population based dopamine exocytosis measurements to obtain biologically significant information that can be relevant in, for instance, the study of neural stem cell differentiation into dopaminergic neurons.


Asunto(s)
Técnicas de Química Analítica/instrumentación , Dopamina/análisis , Dopamina/metabolismo , Polímeros/química , Pirroles/química , Animales , Diferenciación Celular , Electroquímica , Exocitosis , Oro/química , Microelectrodos , Oxidación-Reducción , Células PC12 , Polimerizacion , Ratas
11.
Dalton Trans ; 52(11): 3265-3269, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36857677

RESUMEN

Complexes trans-[PdX2L2] (X = Cl and Br), where L is 1-(PR2),2-(CHCH-C(O)Ph)-C6F4 (R = Ph, Cy, and iPr), display phosphorescent emission in the solid state, whereas due to their substantially lower lifetimes, the free ligands exhibit fluorescent behaviour. Alternatively, structurally identical derivatives with halide replaced by CN- or Pd replaced by Pt are non-emissive. DFT calculations explain this diverse behaviour, showing that the hybridization of orbitals of the MX2 moiety with those of the chalcone fragment of ligands is significant only for the LUMO of the emissive compounds. In other words, in our complexes, only MLMCT processes (LM = Metal-perturbed Ligand-centered orbital) lead to observable luminescence.

12.
J Nanosci Nanotechnol ; 12(4): 3077-83, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22849068

RESUMEN

In this paper we present a series of experiments showing that vertical self-assembled diphenylalanine peptide nanowires (PNWs) are a suitable candidate material for cellular biosensing. We grew HeLa and PC12 cells onto PNW modified gold surfaces and observed no hindrance of cell growth caused by the peptide nanostructures; furthermore we studied the properties of PNWs by investigating their influence on the electrochemical behavior of gold electrodes. The PNWs were functionalized with polypyrrole (PPy) by chemical polymerization, therefore creating conducting peptide/polymer nanowire structures vertically attached to a metal electrode. The electroactivity of such structures was characterized by cyclic voltammetry. The PNW/PPy modified electrodes were finally used as amperometric dopamine sensors, yielding a detection limit of 3,1 microM.


Asunto(s)
Nanocables , Fenilalanina/análogos & derivados , Animales , Técnicas Biosensibles , División Celular , Dipéptidos , Electrodos , Oro , Células HeLa , Humanos , Microscopía Electrónica de Rastreo , Células PC12 , Fenilalanina/química , Ratas
13.
J Sports Sci ; 30(4): 337-47, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22243036

RESUMEN

In this study, we examined the relationships between intrinsic motivation, physical self-concept, and satisfaction with life using cross-lagged panel models analysed via structural equation models. The sample consisted of 293 participants (148 men, 145 women) aged 18-70 years who performed diverse types of physical exercise. Three alternative models were tested. The data were better represented by a model in which physical self-concept mediates the relationships between intrinsic motivation and satisfaction with life. Specifically, the direct effects of intrinsic motivation on physical self-concept, and of physical self-concept on satisfaction with life were significant, with the amount of explained variance increasing over time. In conclusion, people who perform physical exercise regularly, and who have fun over time will tend to have a better physical self-perception and, consequently, more psychological well-being.


Asunto(s)
Ejercicio Físico/psicología , Motivación , Satisfacción Personal , Autoimagen , Adolescente , Adulto , Anciano , Femenino , Humanos , Vida , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelos Psicológicos , Adulto Joven
14.
Span J Psychol ; 15(3): 1466-72, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23156948

RESUMEN

The goals of this research were to translate and analyze the psychometric properties of the Learning Climate Questionnaire (LCQ) and to develop a short form. The LCQ is a 15-item self-report measure that assesses autonomy support in educational settings. A total of 422 students (60 men and 362 women) took part in this study. Results showed evidence of construct validity and adequate reliability for the LCQ. The short form consists of five items that showed sound psychometric properties. Results of Pearson correlation and Gower index showed high agreement between the long and short forms. In conclusion, both forms can be considered as preliminary versions of the original questionnaire to assess autonomy support in educational settings.


Asunto(s)
Relaciones Interpersonales , Aprendizaje , Autonomía Personal , Psicometría/instrumentación , Estudiantes/psicología , Encuestas y Cuestionarios/normas , Humanos , Reproducibilidad de los Resultados , España , Universidades
15.
Chem Commun (Camb) ; 58(19): 3146-3149, 2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-35174831

RESUMEN

An efficient Pd/Cu bimetallic cross-coupling catalysis of fluoroaryl halides and fluoroarenes is reported. In situ generation of the Cu nucleophile by rate determining C-H activation of highly fluorinated aryls (≥4 F atoms) leads to high cross-coupling selectivity with little formation of homocoupling products.

16.
Front Psychol ; 12: 635543, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34290641

RESUMEN

The general purpose of this work is 2-fold, to validate scales and to present the methodological procedure to reduce these scales to validate a rating scale for the student evaluation of teaching in the context of a Polytechnic Higher Education Institution. We explored the relationship between the long and short versions of the scale; examine their invariance in relation to relevant variables such as gender. Data were obtained from a sample of 6,110 students enrolled in a polytechnic higher education institution, most of whom were male. Data analysis included descriptive analysis, intraclass correlation, exploratory structural equation modeling (ESEM), confirmatory factorial analysis, correlations between the short and long form corrected for the shared error variance, gender measurement invariance, reliability using congeneric correlated factors, and correlations with academic achievement for the class as unit with an analysis following a multisection design. Results showed four highly correlated factors that do not exclude a general factor, with an excellent fit to data; configural, metric, and scalar gender measurement invariance; high reliability for both the long and short scale and subscales; high short and long-form scale correlations; and moderate but significant correlations between the long and short versions of the scales with academic performance, with individual and aggregate data collected from classes or sections. To conclude, this work shows the possibility of developing student evaluation of teaching scales with a short form scale, which maintains the same high reliability and validity indexes as the longer scale.

18.
Chem Commun (Camb) ; 57(83): 10875-10878, 2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34590665

RESUMEN

Highly selective cross-couplings to polyfluorinated assymmetric biaryls, including the symmetric biaryl C6F5-C6F5, are achieved at relatively low temperature (80 °C) and in short times using [MCl2(PhPEWO-F)] catalysts (M = Ni, Pd; PhPEWO-F = 1-(PPh2), 2-(CHCH-C(O)Ph)-C6F4), ArFI, and Zn(C6F5)2 as example of highly fluorinated nucleophile.

19.
Chem Commun (Camb) ; 57(44): 5458-5461, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33954313

RESUMEN

The almost quantitative synthesis of homologous luminescent fluorophosphoranes, by SNAr cyclization of (2'-F,2-(PR2)biaryl) phosphines made from easily accessible reagents, is reported and the DFT cyclization mechanism and alternative pathways to complete this isomerization are studied and discussed.


Asunto(s)
Luminiscencia , Fosfinas/química , Ciclización , Estructura Molecular , Fosfinas/síntesis química , Estereoisomerismo
20.
Artículo en Inglés | MEDLINE | ID: mdl-33430506

RESUMEN

This study examines the reciprocal effects between two school-based relationships within the classroom-namely, perceived teacher support and relatedness with classmates-and school aggression (overt and relational) across two courses of secondary education. Participants were 654 adolescents (48% boys), who were assessed in three waves: first, at the beginning of the academic year (T0), second, at the end of the same academic year (T1), and third, at the beginning of the next academic year (T2) (Mage wave 1 = 13.98 years). Autoregressive cross-lagged modeling was applied. Results show a protective effect of relatedness against relational aggression in both genders. Moreover, we observed a protective effect of perceived teacher support at the beginning of the course for later school aggression as well as a risk effect if this perceived teacher support is maintained throughout the course. These effects were observed in relation with gender-atypical forms of aggression (overt in girls and relational in boys). Finally, aggression had negative consequences for relatedness in girls and for teacher support through the mediation of relatedness in boys. Gender differences and practical implications of these findings are discussed.


Asunto(s)
Agresión , Grupo Paritario , Adolescente , Femenino , Humanos , Relaciones Interpersonales , Estudios Longitudinales , Masculino , Instituciones Académicas
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