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1.
J Am Chem Soc ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941615

RESUMO

Periodic responses to nonperiodic energy inputs, such as oscillations, are hallmarks of living systems. Nanoparticle-based systems have largely remained unexplored in the generation of oscillatory features. Here, we demonstrate a nanosystem featuring hierarchical response to light, where thermoplasmonic effects and reversible DNA-hybridization generate thermal convective forces and ultimately, oscillatory hydrodynamic flows. The slow aggregation of gold nanoparticles (AuNPs) serves as a positive feedback, while fast photothermal disassembly acts as negative feedback. These asymmetric feedback loops, combined with thermal hysteresis for time-delay, are essential ingredients for orchestrating an oscillating response.

2.
Nat Chem ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937593

RESUMO

The interactions between gold nanoparticles, their surface ligands and the solvent critically influence the properties of these nanoparticles. Although spectroscopic and scattering techniques have been used to investigate their ensemble structure, a comprehensive understanding of these processes at the nanoscale remains challenging. Electron microscopy makes it possible to characterize the local structure and composition but is limited by insufficient contrast, electron beam sensitivity and the requirement for ultrahigh-vacuum conditions, which prevent the investigation of dynamic aspects. Here we show that, by exploiting high-quality graphene liquid cells, we can overcome these limitations and investigate the structure of the ligand shell around gold nanoparticles and at the ligand-gold interface in a liquid environment. Using this graphene liquid cell, we visualize the anisotropy, composition and dynamics of ligand distribution on gold nanorod surfaces. Our results indicate a micellar model for surfactant organization. This work provides a reliable and direct visualization of ligand distribution around colloidal nanoparticles.

3.
J Phys Chem Lett ; 15(14): 3914-3922, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38564764

RESUMO

Unraveling the nuanced interplay between the morphology and the optical properties of plasmonic nanoparticles is crucial for targeted applications. Managing the relationship becomes significantly complex when dealing with anisotropic nanoparticles that defy a simple description using parameters like length, width, or aspect ratio. This complexity requires computationally intensive numerical modeling and advanced imaging techniques. To address these challenges, we propose a detailed structural parameter determination of gold nanoparticles using their two-dimensional projections (e.g., micrographs). Employing gold bipyramids (AuBPs) as a model morphology, we can determine their three-dimensional geometry and extract optical features computationally for comparison with the experimental data. To validate our inversion model's effectiveness, we apply it to derive the structural parameters of AuBPs undergoing shape modification through oxidative etching. In summary, our findings allow for the precise characterization of structural parameters for plasmonic nanoparticles during shape transitions, potentially enhancing the comprehension of nanocrystal growth and optimizing plasmonic material design for various applications.

4.
ACS Nano ; 18(4): 3323-3330, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38215048

RESUMO

Integrating cavity-enhanced colloidal quantum dots (QDs) into photonic chip devices would be transformative for advancing room-temperature optoelectronic and quantum photonic technologies. However, issues with efficiency, stability, and cost remain formidable challenges to reach the single antenna limit. Here, we present a bottom-up approach that delivers single QD-plasmonic nanoantennas with electrical addressability. These QD nanojunctions exhibit robust photoresponse characteristics, with plasmonically enhanced photocurrent spectra matching the QD solution absorption. We demonstrate electroluminescence from individual plasmonic nanoantennas, extending the device lifetime beyond 40 min by utilizing a 3 nm electron-blocking polymer layer. In addition, we reveal a giant voltage-dependent redshift of up to 62 meV due to the quantum-confined Stark effect and determine the exciton polarizability of the CdSe QD monolayer to be 4 × 10-5 meV/(kV/cm)2. These developments provide a foundation for accessing scalable quantum light sources and high-speed, tunable optoelectronic systems operating under ambient conditions.

5.
Nat Mater ; 23(3): 424-428, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37919350

RESUMO

In principle, designing and synthesizing almost any class of colloidal crystal is possible. Nonetheless, the deliberate and rational formation of colloidal quasicrystals has been difficult to achieve. Here we describe the assembly of colloidal quasicrystals by exploiting the geometry of nanoscale decahedra and the programmable bonding characteristics of DNA immobilized on their facets. This process is enthalpy-driven, works over a range of particle sizes and DNA lengths, and is made possible by the energetic preference of the system to maximize DNA duplex formation and favour facet alignment, generating local five- and six-coordinated motifs. This class of axial structures is defined by a square-triangle tiling with rhombus defects and successive on-average quasiperiodic layers exhibiting stacking disorder which provides the entropy necessary for thermodynamic stability. Taken together, these results establish an engineering milestone in the deliberate design of programmable matter.


Assuntos
DNA , DNA/genética , DNA/química , Termodinâmica
6.
Chemistry ; 30(2): e202302793, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37815406

RESUMO

Temperature-modulated colloidal phase of plasmonic nanoparticles is a convenient playground for resettable soft-actuators or colorimetric sensors. To render reversible clustering under temperature change, bulky ligands are required, especially if anisotropic morphologies are of interest. This study showcases thermoresponsive gold nanorods by employing small surface ligands, bis (p-sulfonatophenyl) phenyl-phosphine dihydrate dipotassium salt (BSPP) and native cationic surfactant. Temperature-dependent analysis in real-time allowed to describe the structural features (interparticle distance and cluster size) as well as thermal parameters, melting and freezing temperatures. These findings suggest that neither covalent Au-S bonds nor bulky ligands are required to obtain a robust thermoresponsive system based on anisotropic gold nanoparticles, paving the way to stimuli-responsive nanoparticles with a wide range of sizes and geometries.

7.
Vox Sang ; 119(1): 27-33, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37986640

RESUMO

BACKGROUND AND OBJECTIVES: The efficacy of COVID-19 convalescent plasma (CP) associates with high titres of antibodies. ConPlas-19 clinical trial showed that CP reduces the risk of progression to severe COVID-19 at 28 days. Here, we aim to study ConPlas-19 donors and characteristics that associate with high anti-SARS-CoV-2 antibody levels. MATERIALS AND METHODS: Four-hundred donors were enrolled in ConPlas-19. The presence and titres of anti-SARS-CoV-2 antibodies were evaluated by EUROIMMUN anti-SARS-CoV-2 S1 IgG ELISA. RESULTS: A majority of 80.3% of ConPlas-19 donor candidates had positive EUROIMMUN test results (ratio ≥1.1), and of these, 51.4% had high antibody titres (ratio ≥3.5). Antibody levels decline over time, but nevertheless, out of 37 donors tested for an intended second CP donation, over 90% were still EUROIMMUN positive, and nearly 75% of those with high titres maintained high titres in the second sample. Donors with a greater probability of developing high titres of anti-SARS-CoV-2 antibodies include those older than 40 years of age (RR 2.06; 95% CI 1.24-3.42), with more than 7 days of COVID-19 symptoms (RR 1.89; 95% CI 1.05-3.43) and collected within 4 months from infection (RR 2.61; 95% CI 1.16-5.90). Male donors had a trend towards higher titres compared with women (RR 1.67; 95% CI 0.91-3.06). CONCLUSION: SARS-CoV-2 CP candidate donors' age, duration of COVID-19 symptoms and time from infection to donation associate with the collection of CP with high antibody levels. Beyond COVID-19, these data are relevant to inform decisions to optimize the CP donor selection process in potential future outbreaks.


Assuntos
COVID-19 , SARS-CoV-2 , Feminino , Humanos , Masculino , Anticorpos Neutralizantes , Anticorpos Antivirais , Doadores de Sangue , COVID-19/terapia , Soroterapia para COVID-19 , Imunização Passiva/métodos , Imunoglobulina G , Ensaios Clínicos como Assunto
8.
RSC Adv ; 13(51): 36023-36034, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38090070

RESUMO

Dye-sensitized solar cells (DSSCs) are an increasingly attractive alternative energy source because of their low cost. Therefore, researchers have intensified efforts over the past decade to increase their energy conversion efficiency by employing new materials in each DSSC component. The present research focuses on synthesizing electrospun nanofibers as a potential new material as a counter electrode in DSSCs. Two Ru(ii) half sandwich 1,10 phenanthroline (phen) Ru-1 and 5-amino- phen Ru-2 complexes were prepared for its functionalization. As a deposition medium, poly(caprolactone) (PCL) dissolved in chloroform was used. Different Ru(ii) complex concentrations were made at 0.1% wt., 0.5% wt., and 1% wt. Thermal characterization studies using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were conducted to evaluate the behavior and weight loss of the samples with temperature variations. Fourier transform infrared spectroscopy (FTIR) measurements were taken to observe the bond interaction of the ruthenium complexes and the PCL. Finally, scanning electron microscopy (SEM) was used to structurally and morphologically evaluate the fiber distribution and porosity. These fibers have a homogeneous morphology, without bulbs, but with evident solid inlays on the surface, with fibers between ∼0.58 to 2.47 µm and percentages of porosity ∼45%. TGA and DSC thermograms show minor temperature variations that demonstrate the incorporation of the Ru(ii) complexes into the fiber. Furthermore, the melting and degradation temperature of the fibers is suitable for use in a DSSC approach. The incorporation of the ruthenium compounds into PCL fibers, along with the addition of the NH2 group into complex Ru-2, resulted in a higher current density for both anodic and cathodic peaks in Cyclic Voltammetry (CV). It is noteworthy that from I-V curves, PCL-Ru2 1% fibers demonstrated a conductivity of 0.461 µS cm-1, which is comparable to other PCL fibers carrying a higher metal load. Future studies will delve into the mechanical properties of these fibers to highlight their potential for application in this field.

9.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1535400

RESUMO

Introducción: Las dinámicas poblacionales, la carga de enfermedad y los cambios estructurales político-económicos han impulsado al estado colombiano a buscar la integralidad en los procesos de atención en salud, en tal propósito definió la implementación de rutas integrales de atención en salud (RIAS). Objetivo: Comprender la percepción de la experiencia que tienen los líderes de proceso en entidades sanitarias referente a la implementación de las RIAS en Cauca, Colombia. Método: Estudio cualitativo, inductivo, con enfoque de fenomenología interpretativa. El grupo de estudio estuvo conformado por siete líderes de proceso de entidades sanitarias. Resultados: Los entrevistados sienten que la implementación es un proceso difícil, determinado por la voluntad y compromiso de los actores sanitarios. Los cambios de administración generan discontinuidades afectando avances en las rutas de la que ellos son responsables. Perciben desarticulación en la implementación, limitados recursos, deficiencia administrativa, de infraestructura y talento humano, principalmente especialistas en salud. Discusión: La percepción de las experiencias denota lo que varios autores han descrito en relación con tensiones en procesos de implementación y gestión en salud: inaccesibilidad, discontinuidad y fragmentación de servicios; débil autoridad sanitaria, enfoque curativo e intereses económicos. Conclusiones: Desde su experiencia, los líderes del proceso perciben las RIAS como un fundamento estratégico que favorece la atención integral en salud, sin embargo, existen vacíos en la implementación originados de procesos administrativos, financieros y del propio modelo de salud, restringiendo el cumplimiento del propósito para las cuales fueron creadas. A la vez, perciben sentimientos de impotencia y desesperanza, dificultades y tensiones en el ejercicio de la implementación.


Introduction: Population dynamics, disease burden and political-economic structural changes have prompted the Colombian state to seek comprehensiveness in health care processes, and to this end it defined the implementation of Integrated Health Care Routes (RIAS). Objective: To understand the perception of the experience of process leaders in health entities regarding the implementation of the RIAS in Cauca, Colombia. Method: Qualitative, inductive study with an interpretative phenomenology approach. The study group consisted of seven process leaders of health entities. Results: The interviewees feel that implementation is a difficult process, determined by the willingness and commitment of the health stakeholders. Changes in administration generate discontinuities affecting progress on the routes for which they are responsible. They perceive disarticulation in implementation, limited resources, administrative deficiencies, infrastructure and human talent, mainly health specialists. Discussion: The perception of the experiences denotes what several authors have described in relation to tensions in implementation and management processes in health: inaccessibility, discontinuity and fragmentation of services; weak health authority, curative approach and economic interests. Conclusions: From their experience, process leaders perceive the RIAS as a strategic foundation that favors comprehensive health care; however, there are gaps in the implementation caused by administrative and financial processes and the health model itself, restricting the fulfillment of the purpose for which they were created. At the same time, they perceive feelings of helplessness and hopelessness, difficulties and tensions in the implementation exercise.

10.
Nat Commun ; 14(1): 5726, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37714855

RESUMO

Anti-Stokes photoluminescence (PL) is light emission at a higher photon energy than the excitation, with applications in optical cooling, bioimaging, lasing, and quantum optics. Here, we show how plasmonic nano-cavities activate anti-Stokes PL in WSe2 monolayers through resonant excitation of a dark exciton at room temperature. The optical near-fields of the plasmonic cavities excite the out-of-plane transition dipole of the dark exciton, leading to light emission from the bright exciton at higher energy. Through statistical measurements on hundreds of plasmonic cavities, we show that coupling to the dark exciton leads to a near hundred-fold enhancement of the upconverted PL intensity. This is further corroborated by experiments in which the laser excitation wavelength is tuned across the dark exciton. We show that a precise nanoparticle geometry is key for a consistent enhancement, with decahedral nanoparticle shapes providing an efficient PL upconversion. Finally, we demonstrate a selective and reversible switching of the upconverted PL via electrochemical gating. Our work introduces the dark exciton as an excitation channel for anti-Stokes PL in WSe2 and paves the way for large-area substrates providing nanoscale optical cooling, anti-Stokes lasing, and radiative engineering of excitons.

12.
Rev Esp Salud Publica ; 972023 Mar 24.
Artigo em Espanhol | MEDLINE | ID: mdl-36960819

RESUMO

OBJECTIVE: Sexual violence against women is one of the most serious public health problems. Sexual violence cannot be eradicated without addressing the social attitudes that condone it. The objective of this study was to evaluate the social perception of sexual harassment in the workplace of the workers of a hospital in the Comunidad de Madrid. METHODS: A cross-sectional observational study was carried out on the perception of workplace sexual harassment in a sample of workers of the Hospital Universitario Severo Ochoa in the Comunidad de Madrid, through an anonymous survey that collected sociodemographic variables and the Illinois Sexual Harassment Myth Acceptance Scale (ISHMA). A descriptive analysis of the variables and a comparison of means with ANOVA were performed. RESULTS: The survey had been completed by 243 employees (23,5% men; 44,9% workers between 25-35 years old). Statistically significant differences were found regarding gender in the average score of the ISHMA scale (p=0.002), with men presenting greater acceptance of the myths of sexual harassment (mean=2.0974; SD=1.09; n=57) compared to women (mean=2.7261; SD=0.68; n=184). However, in the rest of the variables (professional category [p=0.072], time worked [p=0.406] and age [p>0.251]) no statistically significant differences were found. 11% of the people surveyed considered that women can usually stop unrequested sexual attention by simply telling men that their behaviour is not appreciated. CONCLUSIONS: The percentage of employees that denies the different forms of sexual harassment is high. However, some myths about sexual harassment are accepted.


OBJETIVO: La violencia sexual contra la mujer es uno de los problemas más graves de Salud Pública. Esta no puede erradicarse sin abordar las actitudes sociales que la toleran. El objetivo de este estudio fue evaluar la percepción social sobre el acoso sexual en el ámbito laboral de las personas trabajadoras de un hospital de la Comunidad de Madrid. METODOS: Se realizó un estudio observacional transversal sobre la percepción del acoso sexual laboral en una muestra de trabajadores del Hospital Universitario Severo Ochoa de la Comunidad de Madrid, a través de una encuesta anónima que recogió variables sociodemográficas y la Escala validada de Illinois de Aceptación del Mito del Acoso Sexual (ISHMA). Se realizó un análisis descriptivo de las variables y una comparación de medias con ANOVA. RESULTADOS: La encuesta la completaron 243 trabajadores (23,5% hombres; 44,9% tenía entre 25-35 años). Se encontraron diferencias estadísticamente significativas respecto al género en la puntuación media de la escala ISHMA (p=0,002), presentando lo hombres mayor aceptación de los mitos del acoso sexual (media=2,0974; DT=1,09; n= 57) respecto a las mujeres (media=2,7261; DT=0,68; n=184). No obstante, en el resto de las variables (categoría profesional [p=0,072], tiempo trabajado [p=0,406] y edad [p>0,251]) no se encontraron diferencias estadísticamente significativas. Un 11% de las personas encuestadas consideraba que las mujeres pueden hacer que los hombres dejen de fijarse sexualmente en ellas si estas les piden que dejen de hacerlo. CONCLUSIONES: El porcentaje de trabajadores que rechaza las distintas formas de acoso sexual es alto. Sin embargo, existen algunos mitos sobre acoso sexual que son bastante aceptados.


Assuntos
Assédio Sexual , Masculino , Humanos , Feminino , Adulto , Estudos Transversais , Espanha , Local de Trabalho , Percepção Social , Inquéritos e Questionários , Atenção à Saúde
13.
ACS Nano ; 17(6): 5785-5798, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36920091

RESUMO

Multidimensional particle properties determine the product properties in numerous advanced applications. Accurate and statistically meaningful measurements of complex particles and their multidimensional distributions are highly challenging but strongly needed. 2D particle size distributions of plasmonic nanoparticles of complex regular shape can be obtained from analytical ultracentrifugation experiments via the optical back coupling method. A workflow for the calculation of frictional properties of arbitrarily shaped nanoparticles was developed based on bead shell models and applied to gold bipyramids with a pentagonal cross-section. The obtained 2D particle length-diameter distributions and the reduced cumulative 1D length and diameter distributions were compared to transmission electron microscopy measurements. While we find very good agreement for most measurements, the obtained length and diameter distributions were shifted by a few nanometers for some samples. Transmission electron microscopy, energy-dispersive X-ray spectroscopy, electron tomography, and finite element modeling indicate that the shift originated from a slight mismatch between the assumed shape of the simulated perfect bipyramids and the real particle shape and composition due to the presence of silver in the particles. This study demonstrates the feasibility of the applied techniques for complex shape analysis of nanoparticle ensembles with unmatched particle count numbers.

14.
Vox Sang ; 118(4): 296-300, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36734378

RESUMO

BACKGROUND AND OBJECTIVES: There is a concern about a possible deleterious effect of pathogen reduction (PR) with methylene blue (MB) on the function of immunoglobulins of COVID-19 convalescent plasma (CCP). We have evaluated whether MB-treated CCP is associated with a poorer clinical response compared to other inactivation systems at the ConPlas-19 clinical trial. MATERIALS AND METHODS: This was an ad hoc sub-study of the ConPlas-19 clinical trial comparing the proportion of patients transfused with MB-treated CCP who had a worsening of respiration versus those treated with amotosalen (AM) or riboflavin (RB). RESULTS: One-hundred and seventy-five inpatients with SARS-CoV-2 pneumonia were transfused with a single CCP unit. The inactivation system of the CCP units transfused was MB in 90 patients (51.4%), RB in 60 (34.3%) and AM in 25 (14.3%). Five out of 90 patients (5.6%) transfused with MB-treated CCP had worsening respiration compared to 9 out of 85 patients (10.6%) treated with alternative PR methods (p = 0.220). Of note, MB showed a trend towards a lower rate of respiratory progressions at 28 days (risk ratio, 0.52; 95% confidence interval, 0.18-1.50). CONCLUSION: Our data suggest that MB-treated CCP does not provide a worse clinical outcome compared to the other PR methods for the treatment of COVID-19.


Assuntos
COVID-19 , Humanos , COVID-19/terapia , Soroterapia para COVID-19 , Imunização Passiva/métodos , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , SARS-CoV-2 , Resultado do Tratamento
15.
Antioxidants (Basel) ; 12(2)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36829930

RESUMO

Osteoarthritis (OA) is hallmarked as a silent progressive rheumatic disease of the whole joint. The accumulation of inflammatory and catabolic factors such as IL6, TNFα, and COX2 drives the OA pathophysiology into cartilage degradation, synovia inflammation, and bone destruction. There is no clinical available OA treatment. Although traditional ayurvedic medicine has been using Boswellia serrata extracts (BSE) as an antirheumatic treatment for a millennium, none of the BSE components have been clinically approved. Recently, ß boswellic acid (BBA) has been shown to reduce in vivo OA-cartilage loss through an unknown mechanism. We used computational pharmacology, proteomics, transcriptomics, and metabolomics to present solid evidence of BBA therapeutic properties in mouse and primary human OA joint cells. Specifically, BBA binds to the innate immune receptor Toll-like Receptor 4 (TLR4) complex and inhibits both TLR4 and Interleukin 1 Receptor (IL1R) signaling in OA chondrocytes, osteoblasts, and synoviocytes. Moreover, BBA inhibition of TLR4/IL1R downregulated reactive oxygen species (ROS) synthesis and MAPK p38/NFκB, NLRP3, IFNαß, TNF, and ECM-related pathways. Altogether, we present a solid bulk of evidence that BBA blocks OA innate immune responses and could be transferred into the clinic as an alimentary supplement or as a therapeutic tool after clinical trial evaluations.

16.
Adv Sci (Weinh) ; 10(11): e2207178, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36737852

RESUMO

Bottom-up assembly of nanoparticle-on-mirror (NPoM) nanocavities enables precise inter-metal gap control down to ≈ 0.4 nm for confining light to sub-nanometer scales, thereby opening opportunities for developing innovative nanophotonic devices. However limited understanding, prediction, and optimization of light coupling and the difficulty of controlling nanoparticle facet shapes restricts the use of such building blocks. Here, an ultraprecise symmetry-breaking plasmonic nanocavity based on gold nanodecahedra is presented, to form the nanodecahedron-on-mirror (NDoM) which shows highly consistent cavity modes and fields. By characterizing > 20 000 individual NDoMs, the variability of light in/output coupling is thoroughly explored and a set of robust higher-order plasmonic whispering gallery modes uniquely localized at the edges of the triangular facet in contact with the metallic substrate is found. Assisted by quasinormal mode simulations, systematic elaboration of NDoMs is proposed to give nanocavities with near hundred-fold enhanced radiative efficiencies. Such systematically designed and precisely-assembled metallic nanocavities will find broad application in nanophotonic devices, optomechanics, and surface science.

17.
ACS Nano ; 17(1): 743-751, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36525616

RESUMO

The mechanical properties and stability of metal nanoparticle colloids under high-pressure conditions are investigated by means of optical extinction spectroscopy and small-angle X-ray scattering (SAXS), for colloidal dispersions of gold nanorods and gold nanospheres. SAXS allows us to follow in situ the structural evolution of the nanoparticles induced by pressure, regarding both nanoparticle size and shape (form factor) and their aggregation through the interparticle correlation function S(q) (structure factor). The observed behavior changes under hydrostatic and nonhydrostatic conditions are discussed in terms of liquid solidification processes yielding nanoparticle aggregation. We show that pressure-induced diffusion and aggregation of gold nanorods take place after solidification of the solvent. The effect of nanoparticle shape on the aggregation process is additionally discussed.

18.
J Microbio Robot ; 19(1-2): 37-45, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38161388

RESUMO

Micro-and nanorobots have the potential to perform non-invasive drug delivery, sensing, and surgery in living organisms, with the aid of diverse medical imaging techniques. To perform such actions, microrobots require high spatiotemporal resolution tracking with real-time closed-loop feedback. To that end,  photoacoustic imaging has appeared as a promising technique for imaging microrobots in deep tissue with higher molecular specificity and contrast. Here, we present different strategies to track magnetically-driven micromotors with improved contrast and specificity using dedicated contrast agents (Au nanorods and nanostars). Furthermore, we discuss the possibility of improving the light absorption properties of the employed nanomaterials considering possible light scattering and coupling to the underlying metal-oxide layers on the micromotor's surface. For that, 2D COMSOL simulation and experimental results were correlated, confirming that an increased spacing between the Au-nanostructures and the increase of thickness of the underlying oxide layer lead to enhanced light absorption and preservation of the characteristic absorption peak. These characteristics are important when visualizing the micromotors in a complex in vivo environment, to distinguish them from the light absorption properties of the surrounding natural chromophores. Supplementary Information: The online version contains supplementary material available at 10.1007/s12213-023-00156-7.

19.
Int J Nanomedicine ; 17: 5747-5760, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466783

RESUMO

Introduction: A great challenge in nanomedicine, and more specifically in theranostics, is to improve the specificity, selectivity, and targeting of nanomaterials towards target tissues or cells. The topical use of nanomedicines as adjuvants to systemic chemotherapy can significantly improve the survival of patients affected by localized carcinomas, reducing the side effects of traditional drugs and preventing local recurrences. Methods: Here, we have used the Shiga toxin, to design a safe, high-affinity protein-ligand (ShTxB) to bind the globotriaosylceramide receptor (GB3) that is overexpressed on the surfaces of preneoplastic and malignant cancer cells in the head and neck tumors. Results: We find that ShTxB functionalized gold nanorods are efficiently retrotranslocated to the GB3-positive cell cytoplasms. After 3 minutes of laser radiation with a wavelength resonant with the AuNR longitudinal localized surface plasmon, the death of the targeted cancer cells is activated. Both preclinical murine models and patient biopsy cells show the non-cytotoxic nature of these functionalized nanoparticles before light activation and their treatment selectivity. Discussion: These results show how the use of nanomedicines directed by natural ligands can represent an effective treatment for aggressive localized cancers, such as squamous cell carcinoma of the oral cavity.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Nanotubos , Humanos , Animais , Camundongos , Ouro , Toxina Shiga , Neoplasias Bucais/tratamento farmacológico
20.
Aten Primaria ; 54 Suppl 1: 102471, 2022 10.
Artigo em Espanhol | MEDLINE | ID: mdl-36435585

RESUMO

In the 2022 PAPPS update we present those specific preventive activities for women's health, except those related to cancer prevention (which are included in another document) and those aspects related to differential gender morbidity, a cross-cutting aspect for all working groups. Contraception is an essential preventive activity, considering basic the right to decide both the number of children and the time to have them. We must inform about the possible contraceptive methods, guaranteeing the monitoring of their safety, efficacy and effectiveness (tables are included on changing from one method to another to preserve contraceptive protection). We must inform about emergency contraception and propose it in the event of unprotected intercourse. All this will be done through opportunistic screening without requiring screening for thrombophilia or dyslipidemia, but for arterial hypertension. Pregnancy is an important life experience and the family doctor should not remain oblivious. We must be competent both in the preconception consultation (recommending the intake of folic acid, avoiding exposure to occupational and environmental risks, screening for certain pathologies and assessing the intake of drugs not indicated during pregnancy) and in the monitoring of pregnancy. Whether or not we monitor the pregnancy, we must not disregard its control, taking advantage of this period to promote healthy lifestyles and participating in the intercurrent processes that may occur. Menopause in general and osteoporosis in particular exemplify the strategy of medicalization of vital processes that has been followed from different instances and organizations. In our update we address the prevention and treatment of symptoms secondary to estrogen deprivation. We also propose the prevention of osteoporosis, including carrying out densitometry based on the risk of fracture in the next 10 years, and therefore densitometric screening is not recommended in women under 60 years of age. In risk assessment we recommend the use of the frax tool or better, the calibration of the risk of hip fracture with prevalence data from our setting. We linked the indication for treatment with the Z-Score (bone mineral density compared with women of the same age), as it is a condition associated with aging.


Assuntos
Fraturas do Quadril , Osteoporose , Criança , Feminino , Humanos , Osteoporose/tratamento farmacológico , Densidade Óssea , Pós-Menopausa , Medição de Risco/métodos
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