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1.
Crit Care ; 27(1): 417, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37907989

RESUMEN

BACKGROUND: Sepsis is one of the leading causes of death. Treatment attempts targeting the immune response regularly fail in clinical trials. As HCMV latency can modulate the immune response and changes the immune cell composition, we hypothesized that HCMV serostatus affects mortality in sepsis patients. METHODS: We determined the HCMV serostatus (i.e., latency) of 410 prospectively enrolled patients of the multicenter SepsisDataNet.NRW study. Patients were recruited according to the SEPSIS-3 criteria and clinical data were recorded in an observational approach. We quantified 13 cytokines at Days 1, 4, and 8 after enrollment. Proteomics data were analyzed from the plasma samples of 171 patients. RESULTS: The 30-day mortality was higher in HCMV-seropositive patients than in seronegative sepsis patients (38% vs. 25%, respectively; p = 0.008; HR, 1.656; 95% CI 1.135-2.417). This effect was observed independent of age (p = 0.010; HR, 1.673; 95% CI 1.131-2.477). The predictive value on the outcome of the increased concentrations of IL-6 was present only in the seropositive cohort (30-day mortality, 63% vs. 24%; HR 3.250; 95% CI 2.075-5.090; p < 0.001) with no significant differences in serum concentrations of IL-6 between the two groups. Procalcitonin and IL-10 exhibited the same behavior and were predictive of the outcome only in HCMV-seropositive patients. CONCLUSION: We suggest that the predictive value of inflammation-associated biomarkers should be re-evaluated with regard to the HCMV serostatus. Targeting HCMV latency might open a new approach to selecting suitable patients for individualized treatment in sepsis.


Asunto(s)
Infecciones por Citomegalovirus , Sepsis , Humanos , Citomegalovirus , Infecciones por Citomegalovirus/complicaciones , Inmunidad , Interleucina-6 , Sepsis/complicaciones
2.
Chem Soc Rev ; 49(15): 5140-5158, 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32597430

RESUMEN

Covalent long-range ordered (crystalline) sheets called 2D polymers have recently been synthesized by irradiating single crystals of suitably packed monomers. To have such an action proceed successfully, billions of bond formation processes have to be mastered exclusively in two dimensions within 3D crystals. This raises questions as to how to elucidate the mechanism of these unusual polymerizations as well as their entire strain management. The article will show that single crystal X-ray diffraction based on both Bragg and diffuse scattering are powerful techniques to achieve such goal. The very heart of both techniques will be explained and it will be shown what can be safely concluded with their help and what not. Consequently, the reader will understand why some crystals break during polymerization, while others stay intact. This understanding will then be molded into a few guidelines that should help pave the way for future developments of 2D polymers by those interested in joining the effort with this fascinating and emerging class of 2D materials.

3.
Eur J Neurol ; 27(8): 1364-1373, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32320108

RESUMEN

BACKGROUND AND PURPOSE: BSCL2 heterozygote mutations are a common cause of distal hereditary motor neuropathies (dHMNs). A series of BSCL2 patients is presented and clinical, neurophysiological and muscle magnetic resonance imaging (MRI) findings are correlated. METHODS: Twenty-six patients from five families carrying the p.N88S mutation were identified. Age of onset, clinical phenotype (dHMN, Charcot-Marie-Tooth, spastic paraplegia), physical examination, disability measured as a modified Rankin Scale score and neurophysiological findings were collected. A whole body muscle MRI had been performed in 18 patients. The pattern of muscle involvement on T1-weighted and short time inversion recovery sequences was analysed. Hierarchical analysis using heatmaps and an MRI Composite Score were generated. Statistical analysis was carried out with STATA SE v.15 (TX, USA). RESULTS: The mean age was 51.54 ± 19.94 years and 14 patients were men. dHMN was the most common phenotype (50%) and five patients (19.23%) showed no findings on examination. Disease onset was commonly in childhood and disability was low (modified Rankin Scale score 1.34 ± 1.13) although median time since onset of disease was 32 years (range 10-47). Charcot-Marie-Tooth-like patients were more disabled and disability correlated with age. On muscle MRI, thenar eminence, soleus and tibialis anterior were most frequently involved, irrespective of clinical phenotype. MRI Composite Score was strongly correlated with disability. CONCLUSION: Patients with the p.N88S BSCL2 gene mutation are phenotypically variable, although dHMN is most frequent and generally slowly progressive. Muscle MRI pattern is consistent regardless of phenotype and correlates with disease severity, probably serving as a reliable outcome measure for future clinical trials.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth , Subunidades gamma de la Proteína de Unión al GTP/metabolismo , Neuropatía Hereditaria Motora y Sensorial , Adulto , Anciano , Enfermedad de Charcot-Marie-Tooth/diagnóstico por imagen , Enfermedad de Charcot-Marie-Tooth/genética , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mutación , Fenotipo
4.
Angew Chem Int Ed Engl ; 59(14): 5683-5695, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-31821673

RESUMEN

2D polymer sheets with six positively charged pyrylium groups at each pore edge in a stacked single crystal can be transformed into a 2D polymer with six pyridines per pore by exposure to gaseous ammonia. This reaction furnishes still a crystalline material with tunable protonation degree at regular nano-sized pores promising as separation membrane. The exfoliation is compared for both 2D polymers with the latter being superior. Its liquid phase exfoliation yields nanosheet dispersions, which can be size-selected using centrifugation cascades. Monolayer contents of ≈30 % are achieved with ≈130 nm sized sheets in mg quantities, corresponding to tens of trillions of monolayers. Quantification of nanosheet sizes, layer number and mass shows that this exfoliation is comparable to graphite. Thus, we expect that recent advances in exfoliation of graphite or inorganic crystals (e.g. scale-up, printing etc.) can be directly applied to this 2D polymer as well as to covalent organic frameworks.

5.
J Am Chem Soc ; 141(25): 9867-9871, 2019 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-31244135

RESUMEN

Structural elucidation of 2D polymer monolayers proving long-range order is a challenge that limits the pace in which this recent field of polymer chemistry and of synthetic 2D materials develops. To overcome this bottleneck, we here present a method in which tip-enhanced Raman spectroscopy is combined with a random growth crystallization model to obtain global features from local spectroscopic information. Concretely, we prove the nature and determine the conversion number X of the cross-links for two new 2D homopolymers and one (of three) new 2D copolymers. Assuming random and in-plane growth, our model results in crystallinity degrees of 93.1% to 99.7% and mean radii of defect-free crystalline areas of 3-15 nm for conversion numbers of 84% < X < 98%. Thus, we provide strong evidence for the synthetic monolayer 2D materials presented that they qualify as 2D polymers and are therefore perfectly suited for in-depth studies both in a more fundamental direction as well as toward application. This example shows how our method can affect current research on covalent sheets.

6.
Soft Matter ; 15(32): 6547-6556, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31359025

RESUMEN

Dendronized polymers (DPs) are large and compact main-chain linear polymers with a cylindrical shape and cross-sectional diameters of up to ∼15 nm. They are therefore considered molecular objects, and it was of interest whether given their experimentally accessible, well-defined dimensions, the density of individual DPs could be determined. We present measurements on individual, deposited DP chains, providing molecular dimensions from scanning and transmission electron microscopy and mass-per-length values from quantitative scanning transmission electron microscopy. These results are compared with density values obtained from small-angle X-ray scattering on annealed bulk specimen and with classical envelope density measurements, obtained using hydrostatic weighing or a density gradient column. The samples investigated comprise a series of DPs with side groups of dendritic generations g = 1-8. The key findings are a very large spread of the density values over all samples and methods, and a consistent increase of densities with g over all methods. While this work highlights the advantages and limitations of the applied methods, it does not provide a conclusive answer to the question of which method(s) to use for the determination of densities of individual molecular objects. We are nevertheless confident that these first attempts to answer this challenging question will stimulate more research into this important aspect of polymer and soft matter science.

7.
Macromol Rapid Commun ; 40(1): e1800719, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30565776

RESUMEN

This feature article provides both a critical perspective as to where synthetic 2D polymers currently stand and a rather substantial view into how the future of this exciting field of polymer chemistry might look. It starts out by addressing strategic considerations meant to familiarize the reader with what to expect when entering the field. To better understand these considerations, the very nature of a 2D polymer is addressed in comparison to other organic 2D materials. Thereafter, the article moves quite intensely and critically into synthetic and mechanistic issues of 2D polymers before concentrating on the important structural analytics that one has to go through when unequivocally establishing these novel sheet-like polymeric objects. After a short excursion into the matter of exfoliation, the feature article then culminates in a section attempting to forecast the future. Key differences between 1D and 2D polymers are highlighted, and those considered by the authors to be the most attractive and burning research goals are further discussed. It is hoped that the reader will find this speculative section inspiring enough such that ideas that will help in advancing 2D polymers even faster are generated.


Asunto(s)
Polímeros/síntesis química , Estructura Molecular , Tamaño de la Partícula , Polímeros/química , Propiedades de Superficie
8.
Chimia (Aarau) ; 73(6): 487-492, 2019 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-38549211

RESUMEN

Recent breakthroughs in the single crystal approach to synthetic 2D polymers have shifted the limelight onto these long-range ordered sheet-like polymers synthesized at the air/water interface, where one obtains them as laterally macroscopic monolayers without the need for exfoliation. The article presents the most recent monomers for this approach and shows an important analytical development in the field of structure elucidation as well as findings relevant to potential applications. The analytical development concerns an indirect method to establish crystallinity of 2D polymer monolayers based on a combination of tip-enhanced Raman spectroscopy and a crystallization model. The more application-oriented aspects concern the use of ordered 1-1.5 nm thick monomer arrays for laser-triggered writing and for a novel type of lithography both based on a two-dimensional polymerization.

9.
Z Rheumatol ; 78(5): 458-460, 2019 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-30838437

RESUMEN

This article reports the case of a 34-year-old male patient presenting with neck pain, massive pressure pain of the neck muscles and limited cervical rotational mobility. Laboratory tests showed elevated levels for markers of inflammation. Computed tomography (CT) and magnetic resonance imaging (MRI) detected a retropharyngeal tendinitis of the longus cervicis muscle. This rare clinical entity is probably responsible for a high number of unreported cases. A CT scan, which can identify prevertebral edema and light calcification inferior to the ventral aspect of the second cervical vertebra, was previously the gold standard. Meanwhile, MRI scans now show a higher sensitivity in the detection of prevertebral edema. The first line treatment is the administration of non-steroidal anti-inflammatory drugs (NSAIDs).


Asunto(s)
Calcinosis , Tendinopatía , Adulto , Calcinosis/diagnóstico por imagen , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética , Masculino , Dolor de Cuello/diagnóstico por imagen , Tendinopatía/diagnóstico por imagen , Tomografía Computarizada por Rayos X
10.
Clin Exp Immunol ; 191(3): 255-267, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29058307

RESUMEN

Experimental models of Graves' hyperthyroid disease accompanied by Graves' orbitopathy (GO) can be induced efficiently in susceptible inbred strains of mice by immunization by electroporation of heterologous human TSH receptor (TSHR) A-subunit plasmid. In this study, we report on the development of a bona fide murine model of autoimmune Graves' disease induced with homologous mouse TSHR A-subunit plasmid. Autoimmune thyroid disease in the self-antigen model was accompanied by GO and characterized by histopathology of hyperplastic glands with large thyroid follicular cells. Examination of orbital tissues showed significant inflammation in extra-ocular muscle with accumulation of T cells and macrophages together with substantial deposition of adipose tissue. Notably, increased levels of brown adipose tissue were present in the orbital tissue of animals undergoing experimental GO. Further analysis of inflammatory loci by 19 F-magnetic resonance imaging showed inflammation to be confined to orbital muscle and optic nerve, but orbital fat showed no difference in inflammatory signs in comparison to control ß-Gal-immunized animals. Pathogenic antibodies induced to mouse TSHR were specific for the self-antigen, with minimal cross-reactivity to human TSHR. Moreover, compared to other self-antigen models of murine Graves' disease induced in TSHR knock-out mice, the repertoire of autoantibodies to mouse TSHR generated following the breakdown of thymic self-tolerance is different to those that arise when tolerance is not breached immunologically, as in the knock-out models. Overall, we show that mouse TSHR A-subunit plasmid immunization by electroporation overcomes tolerance to self-antigen to provide a faithful model of Graves' disease and GO.


Asunto(s)
Autoantígenos/inmunología , Enfermedad de Graves/inmunología , Oftalmopatía de Graves/inmunología , Inflamación/inmunología , Nervio Óptico/inmunología , Receptores de Tirotropina/inmunología , Tiroiditis Autoinmune/inmunología , Animales , Autoanticuerpos/genética , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Femenino , Humanos , Inmunización , Ratones , Ratones Endogámicos , Ratones Noqueados , Miositis Orbitaria , Plásmidos/inmunología , Receptores de Tirotropina/genética , Autotolerancia
11.
Chemistry ; 24(56): 15003-15012, 2018 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-29984526

RESUMEN

In this work we present one of the rare cases of single-crystal-to-single-crystal (SCSC) linear polymerizations, resulting in a novel ladder-type polymer. The polymerization is based on the photoinduced [4+4]-cycloaddition reactions between trifunctional anthracene-based monomers. The careful design of the monomer anthraphane-tri(OMe), results in perfectly stacked anthracene pairs in the crystal structure, with Schmidt's distances d=3.505-3.666 Šand shift s=1.109 Å, allowing a selective linear polymerization in quantitative yields and in a matter of minutes, without compromising the integrity of the single crystals. The obtained polyanthraphane-tri(OMe), reveals moreover a very interesting and unprecedented case of stereoisomerism, which is characteristic for polyanthraphanes.

12.
HNO ; 66(9): 686-692, 2018 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-30030571

RESUMEN

BACKGROUND: Patients with facial paralysis are significantly limited in their quality of life (QoL). If no irreversible nerve damage is apparent, intensive training of the facial muscles is recommended in addition to drug-based therapy with cortisone. In order to improve training, we have developed a digital biofeedback mirror with motion magnification to indirectly influence the vegetative nervous system. OBJECTIVE: The aim of this work was to evaluate the reliability of the biofeedback program compared to clinical examination and classification according to House-Brackmann. METHODS: Our biofeedback system is similar to a mirror with the additional advantage of increasing a patient's self-control. It not only reflects the patient's image, but also potentiates movement through video processing and a magnifying function. For this purpose, patient's facial movements are filmed and amplified in real-time. Thus, even the smallest movements can be made visible and measured so that patients receive feedback on nerve regeneration. This can increase patient's motivation for daily facial muscle training and improve compliance. RESULTS: In the present study, restriction of QoL was evaluated and objectivized with Facial Clinimetric Evaluation Scale (FaCE) and Facial Disability Index (FDI) questionnaires. It was demonstrated that the patients' self-perception was associated with poor QoL. CONCLUSION: In the current study, measurement of the facial movements showed a reliable agreement with the clinical classification according to House-Brackmann. The biofeedback system is a reliable support tool during the regeneration phase in patients with facial paralysis..


Asunto(s)
Biorretroalimentación Psicológica , Parálisis Facial , Músculos Faciales , Parálisis Facial/terapia , Humanos , Calidad de Vida , Reproducibilidad de los Resultados
13.
Angew Chem Int Ed Engl ; 57(42): 13748-13763, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-29845730

RESUMEN

Periodic and nanoporous monolayer polymers, the structures of which can be viewed as molecular fishing nets, have been classified as 2D polymers. They have been previously synthesized under mild photoirradiation conditions in the interior of layered single crystals of well-designed monomers, followed by a liquid-phase exfoliation. While these mild conditions allow for full structure control, the size of 2D polymers obtained cannot exceed that of the crystals from which they are prepared. In this Review, we discuss different concepts currently pursued to prepare macroscopically sized 2D polymers, focusing on syntheses at the air-water and liquid-liquid interfaces. While these interfaces are larger reaction loci than single crystals, sheet-like polymers obtained at them pose complex and time-consuming analytical challenges. Some of these challenges are concretely discussed and indicators are provided for identifying the promising cases, enabling to concentrate on them in the future research. Additionally, this Review discusses three representative examples of 2D polymers to provide a state-of-the-art picture of this emerging field of polymer and materials science. Finally, we sketch the range of applications, such as nanomembranes, electronics, optoelectronics, and electrocatalysts for water splitting, that are relevant for these novel organic 2D materials.

14.
Angew Chem Int Ed Engl ; 57(33): 10584-10588, 2018 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-29888847

RESUMEN

A trifunctional, partially fluorinated anthracene-substituted triptycene monomer was spread at an air/water interface into a monolayer, which was transformed into a long-range-ordered 2D polymer by irradiation with a standard UV lamp. The polymer was analyzed by Brewster angle microscopy, scanning tunneling microscopy measurements, and non-contact atomic force microscopy, which confirmed the generation of a network structure with lattice parameters that are virtually identical to a structural model network based on X-ray diffractometry of a closely related 2D polymer. The nc-AFM images highlight the long-range order over areas of at least 300×300 nm2 . As required for a 2D polymer, the pore sizes are monodisperse, except for the regions where the network is somewhat stretched because it spans over protrusions. Together with a previous report on the nature of the cross-links in this network, the structural information provided herein leaves no doubt that a 2D polymer has been synthesized under ambient conditions at an air/water interface.

15.
J Am Chem Soc ; 139(5): 2053-2059, 2017 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-28084075

RESUMEN

The single-crystal-to-single-crystal (scsc) synthesis of a 2D polymer based on photochemically triggered [2 + 2]-cycloaddition is reported. Both monomer and polymer single crystals are analyzed by X-ray diffraction, which is the first case of a scsc two-dimensional polymerization based on this cycloaddition and the third ever case for a scsc synthesis of a 2D polymer. The product crystals at quantitative conversion are wet-exfoliated under mild conditions and afford countless features that are single and double layers as judged by their AFM heights of hAFM ≈ 1.2 ± 0.5 and 2.2 ± 0.5 nm, respectively. The X-ray-structure-based molecular weight of the 2D polymers and their degree of polymerization per µm2 are M = 360 MDa and Pn = 464 900, respectively. The sheet size is on the order of 5 × 5 µm2.

16.
Langmuir ; 33(7): 1646-1654, 2017 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-28125880

RESUMEN

The behavior of compound 2 [1,3,5-tri(2,2'-bipyridin-5-yl)benzene] with three bipyridine units arranged in a star geometry is investigated in the presence and absence of Ni(ClO4)2. Its properties at the air-water interface as well as after transfer onto a solid substrate are studied by several techniques including Brewster angle microscopy, X-ray reflectivity, neutron reflectivity, X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, and atomic force microscopy combined with optical microscopy. It is found that compound 2 within the monolayers formed stays almost vertical at the interface and that at high Ni2+/2 (Ni2+/2 = 4000, 20'000) ratios two of the three bipyridine units of 2 are complexed, resulting in supramolecular sheets that are likely composed of arrays of linear metal-organic complexation polymers.

17.
Angew Chem Int Ed Engl ; 56(32): 9361-9366, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28597527

RESUMEN

We report an investigation of interfacial fluorinated hydrocarbon (carboxylic-fantrip) monolayers by nanoscale imaging using tip-enhanced Raman spectroscopy (TERS) and density functional theory (DFT) calculations. By comparing TERS images of a sub-monolayer prepared by spin-coating and a π-π-stacked monolayer on Au(111) in which the molecular orientation is confined, specific Raman peaks shift and line widths narrow in the transferred LB monolayer. Based on DFT calculations that take into account dispersion corrections and surface selection rules, these specific effects are proposed to originate from π-π stacking and molecular orientation restriction. TERS shows the possibility to distinguish between a random and locked orientation with a spatial resolution of less than 10 nm. This work combines experimental TERS imaging with theoretical DFT calculations and opens up the possibility of studying molecular orientations and intermolecular interaction at the nanoscale and molecular level.

18.
Angew Chem Int Ed Engl ; 56(48): 15262-15266, 2017 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-28922539

RESUMEN

This work describes a two-dimensional polymerization at an air/water interface and provides, for the first time, direct spectroscopic evidence for the kind of crosslinks formed and for the conversion reached in a covalently bonded monolayer sheet. This evidence was obtained through a combination of a variety of monolayer characterization techniques before and after transfer onto solid substrates, in particular by tip-enhanced Raman spectroscopy (TERS) and TERS mapping after transfer of both the monomer and polymer monolayer onto Au(111). This work is a major advance for the field of 2D polymers synthesized at the air/water interface as it, in principle, allows estimation of the crystallinity by percolation theory and the location of regions with defects.

19.
J Am Chem Soc ; 138(28): 8976-81, 2016 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-27347597

RESUMEN

This work proves the existence and chemical addressability of defined edge groups of a 2D polymer. Pseudohexagonally prismatic single crystals consisting of layered stacks of a 2D polymer are used. They should expose anthracene-based edge groups at the six (100) but not at the two pseudohexagonal (001) and (001̅) faces. The crystals are reacted with the isotopically enriched dienophiles maleic anhydride and a C18-alkyl chain-modified maleimide. In both cases the corresponding Diels-Alder adducts between these reagents and the edge groups are formed as confirmed by solid state NMR spectroscopy. The same applies to a maleimide derivative carrying a BODIPY dye which was chosen for its fluorescence to be out of the range of the self-fluorescence of the 2D polymer crystals stemming from contained template molecules. If the crystals are excited at λ = 633 nm, their (100) faces and thus their rims fluoresce brightly, while the pseudohexagonal faces remain silent. This is visible when the crystals lie on a pseudohexagonal face. Lambda-mode laser scanning microscopy confirms this fluorescence to originate from the BODIPY dye. Micromechanical exfoliation of the dye-modified crystals results in thinner sheet packages which still exhibit BODIPY fluorescence right at the rim of these packages. This work establishes the chemical nature of the edge groups of a 2D polymer and is also the first implementation of an edge group modification similar to end group modifications of linear polymers.

20.
Chemphyschem ; 17(17): 2767-72, 2016 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-27273228

RESUMEN

Aspects of size, structural (im)perfection, inner density, and guest molecule loading capacity of dendronized polymers (DPs) of high generation (6≤g≤8) in aqueous solution are studied using electron paramagnetic resonance spectroscopy on amphiphilic, spin-labeled guest molecules. The results show that the interior of the charged DPs is strongly polar, especially in comparison to their lower generation (1-4) analogues. This is a direct sign that large amounts of water penetrate the DP surface, reflecting the structural (im)perfections of these high-generation DPs and much lower segmental densities than theoretically achievable. Images obtained with atomic force microscopy reveal that the high-generation DPs do not aggregate and give further insights into the structural imperfections. Electron paramagnetic resonance spectroscopic data further show that despite their structural imperfections, these DPs can bind and release large numbers of amphiphilic molecules. It is concluded that attention should be paid to their synthesis, for which a protocol needs to be developed that avoids the relatively large amount of defects generated in the direct conversion of a generation g=4 DP to a generation g=6 DP, which had to be used here.

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