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1.
J Assoc Physicians India ; 72(3): 47-50, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38736117

RESUMEN

BACKGROUND: Gestational hypertension carries a high-risk for adverse maternal and fetal outcomes, and it can also develop into preeclampsia. A relative decrease in parasympathetic and increase in sympathetic activity has been seen in normal pregnancy which returns to baseline after delivery. The present study aimed to detect any abnormality in sympathetic neurofunction in gestational hypertension and to identify its possible association with the development of preeclampsia/eclampsia. METHODS: A prospective, observational study was carried out among gestational hypertensive patients between 24 and 26 weeks of gestation, who were sent to clinical pharmacology clinics for autonomic neurofunction testing, along with their 24-hour urinary protein testing reports. Preisometric handgrip (IHG) and post-IHG differences in diastolic blood pressure (DBP) were noted. The association between Δ DBP and the development of eclampsia/preeclampsia was probed. RESULTS: A total of 52 pregnancy-induced hypertension (PIH) participants, both multigravida (n = 15) and primigravida (n = 37) were included in one arm (PIH arm), and 52 matched (age and gravida) pregnant women, those do not have PIH included in another arm for comparative analysis. On comparing the PIH arm and normal arm, prehand grip DBP (p ≤ 0.0001), posthand grip DBP, and Δ DBP were significantly higher in the PIH arm. Correlation between Δ DBP and 24 hours' proteinuria was observed in the PIH arm, with a significant positive correlation. CONCLUSION: A high-rise in DBP post-IHG exercise is associated with gestational hypertensive mothers and this rise is strongly correlated with the development of preeclampsia and eclampsia, which suggests that addressing sympathetic hyperactivity could be a potential area to target therapeutics while managing gestational hypertension.


Asunto(s)
Eclampsia , Hipertensión Inducida en el Embarazo , Preeclampsia , Sistema Nervioso Simpático , Humanos , Embarazo , Femenino , Preeclampsia/fisiopatología , Preeclampsia/diagnóstico , Hipertensión Inducida en el Embarazo/fisiopatología , Adulto , Estudios Prospectivos , Sistema Nervioso Simpático/fisiopatología , Eclampsia/fisiopatología , Fuerza de la Mano/fisiología , Presión Sanguínea/fisiología , Adulto Joven
3.
Langmuir ; 30(26): 7833-41, 2014 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-24926619

RESUMEN

Herein, we report a new strategy to remove toxic Cr(VI) ion from aqueous solution using metal-organic hybrid gel as sorbent. The gel could be easily synthesized from the commercially available organic ligand 2-mercaptobenzimidazole (2-MBIm) and copper(II) chloride in alcoholic medium. The synthesis involves one-electron reduction of Cu(II) to Cu(I) by 2-MBIm, and then gel formation is triggered through Cu(I)-ligand coordination and extensive hydrogen-bonding interactions involving the "-NH" protons (of 2-MBIm ligand), solvent molecules, and chloride ions. The gel shows entangled network morphology. Different microanalytical techniques (FTIR, powder XRD, FESEM, TEM, rheology etc.) have been employed for complete characterizations of the gel sample. Both Cu(I) (in situ formed) and Cl(-) ions trigger the gel formation as demonstrated from systematic chemical analyses. The gel also exhibits its stimuli-responsive behavior toward different interfering chemical parameters (pH, selective metal ions and anions, selective complexing agents, etc.). Finally the gel shows its redox-responsive nature owing to the distinguished presence of Cu(I) metal centers throughout its structural backbone. And this indeed helps in the effective removal of Cr(VI) ions from aqueous solution. Reduction of Cr(VI) to Cr(III) ions and its subsequent sorption take place in the gel matrix. The reductive removal of Cr(VI) has been quantitatively interpreted through a set of different kinetic measurements/models, and the removal capacity of the gel matrix has been observed to be ∼331 mg g(-1) at pH ∼ 2.7, which is admirably higher than the commonly used adsorbents. However, the capacity decreases with the increase in pH of the solution. The overall removal mechanism has been clearly demonstrated. Again, the gel could also be recycled. Thus, the low-cost and large-scale fabrication of the redox-active metallogel makes it an efficient matrix for the toxic ion removal and hence indicates the high promise of this new generation hybrid material for environmental pollution abatement.


Asunto(s)
Cromo/química , Cobre/química , Adsorción , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/química
4.
J Family Med Prim Care ; 13(5): 1787-1792, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38948621

RESUMEN

Introduction: Systemic lupus erythematosus (SLE), the commonest type of lupus, is an autoimmune multisystemic disorder that can affect any organ system of the body, especially blood vessels and connective tissues, causing widespread inflammation. Pediatric onset of SLE is a rare condition with more hematological involvement. Aim: This study was undertaken to observe various hematological abnormalities and their association with various autoantibodies present in pediatric SLE in Eastern India. Methodology: It was a single-centered, cross-sectional, observational, hospital-based study conducted in the Department of Pediatric Medicine in collaboration with the Department of Rheumatology in IPGME and R and SSKM Hospital, Kolkata. The duration of the study was 1.5 years, and a total of 30 children up to 12 years of age of either gender were enrolled. Study participants were evaluated for various parameters like demographic, hematological (anemia, neutropenia, leucopenia, lymphopenia, and thrombocytopenia), biochemical (CRP, Lactate dehydrogenase (LDH), and bilirubin), autoantibodies (anti-dsDNA, anti-Ro 52, and anti-Ribonucleoprotein [RNP]), and SLE related pathologies (Cutaneous, nephritis, serositis). Results: In the present study, most of the participants had arthritis, muscle pain (86.66%), and hematological involvement (80%). Among cytopenias, anemia was the commonest. dsDNA autoantibody was positive in most of the patients (83%), and about one-third suffered from autoimmune hemolytic anemia (AIHA). No association was observed between autoantibodies and various hematological manifestations. Conclusion: It can be concluded from the present study that anemia is the most common cytopenia in pediatric SLE, but there is no association between autoantibodies and these cytopenias. However, study on larger population may give better results.

5.
Environ Sci Technol ; 47(5): 2339-45, 2013 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-23409805

RESUMEN

Phase pure spherical Sn-SnO2 nanoparticles (∼ 50 nm) in gram level have been synthesized from well-defined SnO microplates (∼ 2.0 µm) using focused solar irradiation. The first step of the reaction involves simple stirring of a strong NaOH solution with fine SnCl2·2H2O powder. Precipitated blue black microplates of SnO are finally transformed into high band gap Sn-SnO2 nanoparticles with sunlight. During the solid-state photodecomposition of microplates, spherical SnO2 nanoparticles along with tiny Sn(0) particles are evolved simultaneously. Tiny Sn(0) particles, improved surface area, stability toward adverse environmental conditions, and inherited negative surface charge electrostatically stabilize the Sn-SnO2 particle rendering it excellent water dispersible. The presence of Sn(0) nanoparticles in spherical SnO2 nanoparticles improves the charge (electrons and holes) separation efficiency. Then, the as-prepared particles selectively invite cationic dye molecules to the particle surface due to negative surface charge and degrade the dyes at a faster rate under UV light.


Asunto(s)
Colorantes/química , Nanopartículas del Metal/química , Luz Solar , Compuestos de Estaño/síntesis química , Agua/química , Procesos Fotoquímicos , Rayos Ultravioleta
6.
Dalton Trans ; 52(42): 15360-15364, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37740280

RESUMEN

Herein, we demonstrate the construction of a 1D/2D heterostructure of cobalt phthalocyanine (CoPc)-carbon nitride (C3N4) for electrochemical N2 reduction to NH3. Improved performance originates from the higher exposure of active surface sites. The electrochemical NRR performance showed an NH3 formation rate of 423.8 µg h-1 mgcat-1, a high faradaic efficiency (FE) of 33%, and stability for 20 h. This study provides a new strategy for designing a highly efficient 1D/2D electrocatalytic system for ammonia synthesis.

7.
Diabetes Metab Syndr ; 17(1): 102703, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36634469

RESUMEN

AIM: This systematic review and meta-analysis was conducted to evaluate the efficacy and safety of lobeglitazone as compared to the standard of care (SOC) in patients with type 2 diabetes mellitus (T2DM). METHODS: Databases were searched for relevant randomized controlled trials. The primary outcome was the comparison of the glycated hemoglobin (HbA1C) level after 24 weeks. Pooled mean differences and odds ratios were calculated using random-effects models. RESULTS: Of 267 studies that were screened, four were included. Treatment with adjunct lobeglitazone showed a reduction in the HbA1C level [mean difference: -0.23% (95% CI: -0.62 to 0.16); p = 0.24; i2: 87%; moderate GRADE (Grading of Recommendations Assessment, Development and. Evaluation) of evidence], fasting blood glucose level [mean difference: -7.12 mg/dl (95% CI: -20.09 to 5.85); p = 0.28; i2: 87%; moderate GRADE of evidence], and lipid profile as compared to those following treatment with the SOC; however, the changes were not statistically significant. The risk of hypoglycemia was significantly lower [odds ratio: 0.24 (95% CI: 0.08 to 0.70); p < 0.05; i2: 0%; moderate GRADE of evidence] without any significant difference in the risk of drug-related adverse events [odds ratio: 1.59 (95% CI: 0.87 to 2.93); p = 0.13; i2: 0%; moderate GRADE of evidence] following treatment with lobeglitazone as compared to those following treatment with the SOC. CONCLUSION: Treatment with adjunct lobeglitazone showed changes in the blood glycemic status and lipid profile similar to SOC in patients with T2DM, and the results were not statistically significant. Lobeglitazone was well tolerated; its safety profile was comparable to SOC.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipoglucemiantes , Tiazolidinedionas , Humanos , Glucemia , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada , Hipoglucemiantes/uso terapéutico , Lípidos , Nivel de Atención , Tiazolidinedionas/uso terapéutico
8.
Chemistry ; 18(20): 6335-42, 2012 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-22473800

RESUMEN

In the present study, surface-enhanced Raman spectra of a bifunctional Raman reporter, 2-mercaptobenzimidazole, has been found to be responsive exclusively towards Cu(2+) ions while the reporter remains anchored on the Au nanoparticle surface. Thus a specific Cu(2+)-ion-detection protocol emerges. The simplicity, sensitivity, and reproducibility of the method allow routine and quantitative detection of Cu(2+) ions. An interference study involving a wide number of other metal ions shows the procedure to be uniquely selective and analytically rigorous. A theoretical study was carried out to corroborate the experimental results. Finally, the method is promising for real-time assessment of Cu(2+) ions in aqueous samples and also has the ability to discriminate Cu(I) and Cu(II) ions in solution.


Asunto(s)
Bencimidazoles/química , Cobre/análisis , Nanopartículas/química , Espectrometría Raman/métodos , Oro/química , Estructura Molecular , Soluciones/química , Estados Unidos , United States Environmental Protection Agency , Agua
9.
Dalton Trans ; 51(34): 12904-12914, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-35946840

RESUMEN

The synthesis of nickel selenide nanostructures under ambient conditions remains fascinating, aesthetically beautiful, and energy efficient, as most reported methods involve high-temperature techniques. In this work, we have reported the wet chemical synthesis of NiSe2 nanostructures at room temperature. The approach starts with nickel nanowires (NiNW) and selenous acid as active ingredients. Upon the incubation of NiNW in selenous acid, zero-valent metallic nickel gradually oxidised with the successive deposition of nano-selenium, a reductive product, over the pristine NiNW surface. This thermodynamically controlled galvanic replacement reaction (GRR) is favourably governed by the reduction potential values of the Ni2+/Ni and SeO32-/Se redox couples. Moreover, the selenium nanoparticles over the NiNW surface and the oxidized Ni2+ underneath then interplay during inward and outward diffusion. The different diffusivities of the elements/ions cause the generation of void interiors, thus resulting in tubular nanostructures. Therefore, both the GRR and nanoscale Kirkendall effect jointly remain engaged, resulting in the formation of hollow NiSe2 nanotubular structures. Then, we ably exploit this heterogeneous chalcogenide nanostructure material as an artificial enzyme for peroxidase mimics. This provides a method for the naked-eye detection of peroxide in solution. The peroxidase activity was selectively restrained in the presence of glutathione. Hence, a colourimetric assay was simultaneously developed for the selective detection of this biothiol. The intrinsic nanozyme activity of the substrate is hitherto unknown and can, hence, be explored further with other nanostructured nickel selenide materials.


Asunto(s)
Níquel , Peroxidasa , Catálisis , Níquel/química , Ácido Selenioso , Temperatura
10.
Geriatrics (Basel) ; 7(6)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36547272

RESUMEN

We assessed the association between polypharmacy and cardiovascular autonomic function among community-dwelling elderly patients having chronic diseases. Three hundred and twenty-one patients from an urban municipality area of Kolkata, India were studied in August 2022. The anticholinergic burden and cardiac autonomic function (Valsalva ratio, orthostatic hypotension, change in diastolic blood pressure after an isometric exercise, and heart rate variability during expiration and inspiration) were evaluated. Binary logistic regression analysis was performed to find out the association of polypharmacy and total anticholinergic burden with cardiac autonomic neuropathy. A total of 305 patients (age, 68.9 ± 3.4; 65.9% male) were included. Of these patients, 81 (26.6%) were on polypharmacy. Out of these 81 patients, 42 patients were on ninety-eight potential inappropriate medications. The anticholinergic burden and the proportion of patients with cardiac autonomic neuropathy were significantly higher among patients who were on polypharmacy than those who were not (8.1 ± 2.3 vs. 2.3 ± 0.9; p = 0.03 and 56.8% vs. 44.6%; p = 0.01). The presence of polypharmacy and a total anticholinergic burden of > 3 was significantly associated with cardiac autonomic neuropathy (aOR, 2.66; 95% CI, 0.91−3.98 and aOR, 2.51; 95% CI, 0.99−3.52, respectively). Thus, polypharmacy was significantly associated with cardiac autonomic neuropathy among community-dwelling elderly patients.

11.
Langmuir ; 27(18): 11629-35, 2011 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-21809875

RESUMEN

Unique packaging of Ag(2)O on the surface of polycrystalline AgCl allows fabrication of a new useful, superhydrophobic composite material. This pure inorganic material with surface porosity of submicrometer aperture size fabricates air pockets, which make the composite material superhydrophobic. The new material behaves like lotus leaves, butterfly wings, or water strider's leg in relation to superhydrophobicity. Visible light induces photoreduction of solid Ag(2)O surface layer and generates Ag(0), making the composite surface superhydrophilic. Reoxidation of Ag(0) on the composite surface gives back the hydrophobicity that represents the redox-switchable wetting property of the material.

12.
Chemistry ; 16(26): 7865-74, 2010 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-20496353

RESUMEN

We report here the preparation of a crystalline, pure hexagonal phase of ZnO as hollow 500-800 nm spheroids in the presence of organic bases, such as pyridine, using zinc acetate as the precursor salt. The spheroids exhibit unique 3D hierarchical architectures, like cocoons, and demonstrate improved superhydrophobic (water contact angle, 150 degrees) character due to the inherited air-trapped capillarity within the cocoon structure. The simple synthetic strategy used in this process is modified hydrothermolysis (MHT), which represents a general approach and may contribute to the formation mechanism of the hollow nanostructures with highly improved porosity. Depending on the concentration of the precursor salt, it has been possible to cover glass plates or the inner wall of a reaction vessel with ZnO nanocrystals. A low salt concentration (<0.01 M) allows the easy preparation of a superhydrophobic glass surface, whereas a high salt concentration (>0.01 M) results in the precipitation of cocoons at the bottom of the reaction vessel as a solid mass together with a deposited thin film of ZnO nanocrystals covering the inner wall of the glass vessel. The thickness of the film successively grows through repetitive hydrothermolysis processes for which a low salt concentration (<0.01 M) was employed. Because of the hollow cocoon-like morphology, the surface area of the film is greatly increased, which makes it accessible for functionalization by incoming substrates from both sides (internally and externally) and helps to drive a competent photocatalytic dye degradation pathway. The heterocyclic base pyridine exclusively develops cocoons. Thus, the mechanism of self-aggregation of ZnO nanocrystals under MHT reaction conditions has been studied and the characterization of the compounds has been supported with physical measurements.

13.
Langmuir ; 26(22): 17419-26, 2010 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-20873846

RESUMEN

We have developed a polarization-induced growth process to synthesize gram quantity of gold nanowire (Au NW) on the outer surface of an anion exchange resin matrix. This new, simple, modified hydrothermolysis (MHT) procedure involving resin-bound HAuCl(4) produced micrometer long Au nanowire on resin surface. The charged resin matrix responsibly imposes electrostatic field effect (EFF) for 1D growth of Au NWs in the presence of different amines or derivatives of amines. The Au nanowire is separated from resin by sonication. Again, the synthesis of MnO(2) nanowire with resin support through similar MHT strengthens the 1D growth proposition, that is, EFF-induced polarization effect.

14.
Langmuir ; 26(8): 5836-42, 2010 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-19894750

RESUMEN

The brilliant red [Fe(bpy)(3)](2+) complex upon immobilization on a strongly acidic cation exchanger or in situ formation of the same cationic complex onto a resin matrix and subsequent modified hydrothermolysis (MHT) at approximately 110 degrees C produces unusually stable hierarchical magnetite (Fe(3)O(4)) nanowafers. The slow hydrothermolysis, oxidation, and subsequent dehydration of the complex on the solid-liquid interface produce stable hierarchical nanostructures. The isolation of neat Fe(3)O(4) (uncapped) particles from the resin matrix as hierarchical nanowafers was achieved by magnetically stirring a CH(3)CN suspension of nanocomposites. The solid resin support not only aids nanowafer formation on its surface but also provides unique stability to the magnetite particles, where nanowafer oxidation is largely retarded. The utility of the as-prepared porous nanocomposite and characterization of the nanoparticles are promising for nanotechnological and soft ferromagnetic applications.

15.
Inorg Chem ; 49(19): 8813-27, 2010 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-20825205

RESUMEN

A surfactantless, trouble-free, and gentle wet chemistry approach has been used to interpret the precisely controlled growth of ß-Ni(OH)(2) with the assistance of ammonia and nickel acetate from seedless mild hydrothermal conditions. A thorough investigation of the reaction kinetics and product morphology with varied concentration of NH(3) and different reaction times suggests that a putative mechanism of dissolution, recrystallization, and oriented attachment supports the intelligent self-assembly of nanobuilding blocks. Associated characterizations (FTIR, PXRD, FESEM, EDAX, HRTEM, and Raman) have identified it to be pure ß-Ni(OH)(2) without any signature of contamination. The assembled units result in porous frameworks (nanoflowers and nanocolumns) and are indeed full of communally intersecting nanopetals/nanoplates with both lengths and widths on the order of micrometer to nanometer length scale. The as-synthesized material could also be used as a precursor for nanometric black NiO under calcination. The hydroxide has been found to be a potent and environmentally benign material because it warrants its photocatalytic activity through dye mineralization. Finally, Ni(OH)(2) has been photochemically derivatized with dosages of silver nanoparticles bringing a competent composite authority Ag@Ni(OH)(2), to give a full-proof enhanced field effect of prolific SERS activity. In a nutshell, these results are encouraging and fetch new promise for the fabrication of a low-cost and high-yielding greener synthetic protocol for a functional material with promising practicability.


Asunto(s)
Hidróxidos/síntesis química , Nanoestructuras/química , Acetatos/química , Amoníaco/química , Catálisis , Hidróxidos/química , Estructura Molecular , Níquel/química , Compuestos Organometálicos/química , Tamaño de la Partícula , Fotoquímica , Porosidad , Plata/química , Espectrometría Raman , Propiedades de Superficie
16.
Environ Sci Technol ; 44(16): 6313-8, 2010 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-20704231

RESUMEN

Blue solution of copper(II) acetylacetonate complex, [Cu(acac)(2)] in dichloromethane (DCM) and an aqueous alkaline solution of thioacetamide (TAA) constitute a biphasic system. The system in a screw cap test tube under a modified hydrothermal (MHT) reaction condition produces a greenish black solid at the liquid-liquid interface. It has been characterized that the solid mass is an assembly of hexagonal copper sulfide (CuS) nanoplates representing a hierarchical structure. The as-synthesized CuS nanoplates are well characterized by several physical techniques. An ethanolic dispersion of CuS presents a high band gap energy (2.2 eV) which assists visible light photocatalytic mineralization of different dye molecules. Thus a cleanup measure of dye contaminated water body even under indoor light comes true.


Asunto(s)
Colorantes/química , Cobre/química , Luz , Fotoquímica , Catálisis/efectos de la radiación , Electrones , Azul de Metileno/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Oxidación-Reducción/efectos de la radiación , Espectrofotometría Ultravioleta , Termodinámica
17.
J Nanosci Nanotechnol ; 10(2): 847-59, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20352727

RESUMEN

A general method has been fabricated to achieve normal as well as inverted core-shell architectures of silver/gold through a layer-by-layer deposition technique on a commercial anion exchange resin. Electrostatic field force of the charged resin beads supports immobilization of anionic metal precursors [MX(n)]-, in turn deposition of silver/gold nanoparticles onto the solid resin matrix and reduction of 2-nitrobenzoic acid to obtain the corresponding amines through effective catalysis. The shell thickness has been tailored made by exploiting a new method of cyclic and repetitive deposition of the desired metal precursors. Thermodynamic parameters for the reduction reaction have been presented. Kinetic study reveals a comparative account of rates between the mono- and bi-metallic nanoparticles where silver stands to be a better catalyst for the reduction of nitroaromatics.

19.
Artículo en Inglés | MEDLINE | ID: mdl-30422758

RESUMEN

Azo linked salicyldehyde and a new 2-hydroxy acetophenone based ligands (HL1 and HL2) with their copper(II) complexes [Cu(L1)2] (1) and [Cu(L2)2] (2) were synthesized and characterized by spectroscopic methods such as 1H, 13C NMR, UV-Vis spectroscopy and elemental analyses. Calculation based on Density Functional Theory (DFT), have been performed to obtain optimized structures. Binding studies of these copper (II) complexes with calf thymus DNA (ct-DNA) and torula yeast RNA (t-RNA) were analyzed by absorption spectra, emission spectra and Viscosity studies and Molecular Docking techniques. The absorption spectral study indicated that the copper(II) complexes of 1 and 2 had intrinsic binding constants with DNA or RNA in the range of 7.6 ± 0.2 × 103 M-1 or 6.5 ± 0.3 × 103M-1 and 5.7 ± 0.4 × 104 M-1 or 1.8 ± 0.5 × 103 M-1 respectively. The synthesized compounds and nucleic acids were simulated by molecular docking to explore more details mode of interaction of the complexes and their orientations in the active site of the receptor.


Asunto(s)
Complejos de Coordinación/química , Complejos de Coordinación/metabolismo , Cobre/química , ADN/metabolismo , Unión Competitiva , Complejos de Coordinación/síntesis química , ADN/química , Teoría Funcional de la Densidad , Ligandos , Espectroscopía de Resonancia Magnética , Simulación del Acoplamiento Molecular , Estructura Molecular , ARN/química , ARN/metabolismo , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Viscosidad
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