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1.
PeerJ ; 12: e17479, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38827295

RESUMEN

Background: Body mass and surface area are among the most important biological properties, but such information is lacking for some extant organisms and most extinct species. Numerous methods have been developed for body size estimation of animals for this reason. There are two main categories of mass-estimating approaches: extant-scaling approaches and volumetric-density approaches. Extant-scaling approaches determine the relationships between linear skeletal measurements and body mass using regression equations. Volumetric-density approaches, on the other hand, are all based on models. The models are of various types, including physical models, 2D images, and 3D virtual reconstructions. Once the models are constructed, their volumes are acquired using Archimedes' Principle, math formulae, or 3D software. Then densities are assigned to convert volumes to masses. The acquisition of surface area is similar to volume estimation by changing math formulae or software commands. This article presents a new 2D volumetric-density approach called the cross-sectional method (CSM). Methods: The CSM integrates biological cross-sections to estimate volume and surface area accurately. It requires a side view or dorsal/ventral view image, a series of cross-sectional silhouettes and some measurements to perform the calculation. To evaluate the performance of the CSM, two other 2D volumetric-density approaches (Graphic Double Integration (GDI) and Paleomass) are compared with it. Results: The CSM produces very accurate results, with average error rates around 0.20% in volume and 1.21% in area respectively. It has higher accuracy than GDI or Paleomass in estimating the volumes and areas of irregular-shaped biological structures. Discussion: Most previous 2D volumetric-density approaches assume an elliptical or superelliptical approximation of animal cross-sections. Such an approximation does not always have good performance. The CSM processes the true profiles directly rather than approximating and can deal with any shape. It can process objects that have gradually changing cross-sections. This study also suggests that more attention should be paid to the careful acquisition of cross-sections of animals in 2D volumetric-density approaches, otherwise serious errors may be introduced during the estimations. Combined with 2D modeling techniques, the CSM can be considered as an alternative to 3D modeling under certain conditions. It can reduce the complexity of making reconstructions while ensuring the reliability of the results.


Asunto(s)
Tamaño Corporal , Animales , Superficie Corporal , Imagenología Tridimensional/métodos
2.
Opt Express ; 32(4): 6266-6276, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439334

RESUMEN

Augmented reality (AR) display, as a next-generation innovative technology, is revolutionizing the ways of perceiving and communicating by overlaying virtual images onto real-world scenes. However, the current AR devices are often bulky and cumbersome, posing challenges for long-term wearability. Metasurfaces have flexible capabilities of manipulating light waves at subwavelength scales, making them as ideal candidates for replacing traditional optical elements in AR display devices. In this work, we propose and fabricate what we believe is a novel reflective polarization multiplexing gradient metasurface based on propagation phase principle to replace the optical combiner element in traditional AR display devices. Our designed metasurface exhibits different polarization modulations for reflected and transmitted light, enabling efficient deflection of reflected light while minimizing the impact on transmitted light. This work reveals the significant potential of metasurfaces in next-generation optical display systems and provides a reliable theoretical foundation for future integrated waveguide schemes, driving the development of next-generation optical display products towards lightweight and comfortable.

3.
Int. j. morphol ; 42(1): 46-51, feb. 2024. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1528827

RESUMEN

SUMMARY: Few international studies have analyzed the characteristics of elite wheelchair curlers competing on the international stage. This study aims to investigate the physical fitness parameters of elite Chinese wheelchair curlers and explore the corresponding training enlightenment. Sixteen wheelchair curlers from the Chinese national team, including six male and two female Winter Paralympic gold medalists, were selected as research participants. The following parameters were measured: age, training age, height, weight, body fat percentage, grip strength, absolute bench press strength, and 5-km wheelchair push-timing test. Compared with ordinary curlers of the Chinese wheelchair curling team, elite curlers were older in age and training age; male curlers were shorter, whereas female curlers were taller. However, their weight and body fat percentage were lower, and their grip strength, absolute strength in the bench press, and 5-k wheelchair push-timing test were better. From an athlete development and physical training perspective, wheelchair curlers should increase training years in order to accumulate competition experience. Additionally, these athletes should manage their body weight and fat percentage, and improve their upper limb strength and aerobic capacity.


Pocos estudios internacionales han analizado las características de los curlers en silla de ruedas de élite que compiten en el escenario internacional. Este estudio tiene como objetivo investigar los parámetros de aptitud física de los bigudíes chinos en silla de ruedas de élite y explorar la iluminación del entrenamiento correspondiente. Se seleccionaron como participantes de la investigación dieciséis curlers en silla de ruedas del equipo nacional chino, incluidos seis medallistas de oro masculinos y dos femeninos de los Juegos Paralímpicos de Invierno. Se midieron los siguientes parámetros: edad, edad de entrenamiento, altura, peso, porcentaje de grasa corporal, fuerza de agarre, fuerza absoluta en press de banca y prueba de sincronización de empuje en silla de ruedas de 5 km. En comparación con los curlers ordinarios del equipo chino de curling en silla de ruedas, los curlers de élite eran mayores en edad y tiempo de entrenamiento; Los curlers masculinos eran más bajos, mientras que las mujeres eran más altas. Sin embargo, su peso y porcentaje de grasa corporal fueron menores, y su fuerza de agarre, fuerza absoluta en press de banca y prueba de sincronización de empuje en silla de ruedas de 5-k fueron mejores. Desde la perspectiva del desarrollo del atleta y del entrenamiento físico, los curlers en silla de ruedas deberían aumentar los años de entrenamiento para acumular experiencia en competencia. Además, estos deportistas deben controlar su peso corporal y porcentaje de grasa, y mejorar la fuerza de sus miembros superiores y su capacidad aeróbica.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Deportes , Silla de Ruedas , Aptitud Física , Antropometría
4.
ACS Appl Mater Interfaces ; 15(43): 50499-50507, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37862618

RESUMEN

Phase-change memory (PCM) is considered one of the most promising candidates for universal memory. However, during the manufacturing process of PCM, phase-change materials (PCMs) encounter severe oxidation, which can cause degraded performance and reduced stability of PCM, hindering its industrialization process. In this work, a multilayered oxygen barrier (MOB) structure is proposed to tackle this challenge. Material characterization shows that the MOB structure can significantly reduce the extent of oxidation of PCMs from around 70% to as low as around 10%, achieving a remarkably low level of oxidation. Moreover, the material in the MOB structure exhibits notable enhancements in crystallization temperature and cycling capability. The improved stability is attributed to the oxygen barrier effect and the suppression of elemental segregation within the material, which are both conferred by the MOB structure. In summary, this work provides an effective solution to address the oxidation of PCMs, offering valuable guidance for realizing a high-reliability PCM in practical production.

5.
Aging (Albany NY) ; 15(19): 10168-10192, 2023 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-37788005

RESUMEN

BACKGROUND: The role of obesity related genes (ORGs) in the immune checkpoint inhibitors (ICIs) treatment of prostate adenocarcinoma (PRAD) has not yet been proved by research. METHODS: We comprehensively evaluated the ORGs patterns in PRAD based on tumor microenvironment (TME) phenotypes and immunotherapy efficacies. Then we constructed a ORGs risk score for prognosis and a ORGs signature for accurate prediction of TME phenotype and immunotherapy efficacy in order to evaluate individual patients. RESULTS: Two distinct ORGs patterns were generated. The two ORGs patterns were consistent with inflammatory and non-inflammatory TME phenotypes. ORGs patterns had an important role for predicting immunotherapy efficacies. Next, we constructed a ORGs risk score for predicting each patient's prognosis with high performance in TCGA-PRAD. The ORGs risk score could be well verified in the external cohorts including GSE70769 and GSE21034. Then, we developed a ORGs signature and found it was significantly positively correlated with tumor-infiltrating lymphocytes in TCGA-PRAD. We found that each patient in the high-risk ORGs signature group represented a non-inflamed TME phenotype on the single cell level. The patients with high ORGs signature had more sensitivity to immunotherapy. And those ORGs were verified. CONCLUSIONS: ORGs pattern depicts different TME phenotypes in PRAD. The ORGs risk score and ORGs signature have an important role for predicting prognosis and immunotherapy efficacies.


Asunto(s)
Adenocarcinoma , Neoplasias de la Próstata , Masculino , Humanos , Próstata , Obesidad/genética , Factores de Riesgo , Fenotipo , Neoplasias de la Próstata/genética , Microambiente Tumoral/genética , Adenocarcinoma/genética , Pronóstico
6.
Nat Commun ; 13(1): 7842, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36543781

RESUMEN

Three-dimensional (3D) imaging is a crucial information acquisition technology for light detection, autonomous vehicles, gesture recognition, machine vision, and other applications. Metasurface, as a subwavelength scale two-dimensional array, offers flexible control of optical wavefront owing to abundant design freedom. Metasurfaces are promising for use as optical devices because they have large field of view and powerful functionality. In this study, we propose a flat optical device based on a single-layer metasurface to project a coded point cloud in the Fourier space and explore a sophisticated matching algorithm to achieve 3D reconstruction, offering a complete technical roadmap for single-shot detection. We experimentally demonstrate that the depth accuracy of our system is smaller than 0.24 mm at a measurement distance of 300 mm, indicating the feasibility of the submillimetre measurement platform. Our method can pave the way for practical applications such as surface shape detection, gesture recognition, and personal authentication.

7.
Opt Express ; 30(12): 20750-20761, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36224812

RESUMEN

The combination of metasurface and holographic technology is the most cutting-edge development, but most of the proposed designs are static and do not allow active changes through external stimulation after fabrication, which takes only a limited part of the advantage provided by metasurface. Here, we propose and demonstrate a switchable hybrid active metasurface hologram in the terahertz (THz) regime composed of dynamic pixels (VO2-CSRR) and static pixels (Au-CSRR) based on an intelligent algorithm, which can display some/all information in different temperature ranges. In particular, such performance shows excellent potential in the field of optical communication security, making it a promising candidate. To prove this possibility, we propose a scheme for optical information encryption/decryption and transmission, which takes metasurfaces as carriers of encrypted information and state/polarization/positions as the secret key components. Only when the two matches correctly can we get the hidden real information. The security of our proposed scheme has reached an unprecedented level, providing a new road for communication security.

8.
Opt Express ; 30(18): 32670-32679, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36242323

RESUMEN

New kinds of dispersion elements are required for the minimization of the spectrometers. Metasurfaces offer new methods for a novel type of spectrometers due to their ultra-thin property and great ability to manipulate the electromagnetic field. Here, we propose and demonstrate a spectral modulated metasurface as a miniaturized dispersion element that possesses parabolic phase profile. Different wavelengths of the incident light can be dispersed to different spatial positions due to the accumulation of the dynamic phase varies with the wavelengths from metasurface. Detailed theoretical spectrum dispersion ability is analyzed and experimental demonstration is achieved. The polarization conversion efficiency is high, which is promising to be used in practical applications. Such metasurface provides a new and simple way to design dispersion devices and has the potential to be used in spectrometers, variable filters, spectrum tomography, etc.

9.
Sci Adv ; 8(40): eabp8073, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36197982

RESUMEN

In mathematics, general functions can be decomposed into a linear combination of basis functions. This principle can be used for creating an infinite number of distinct geometric patterns based on a finite number of basis patterns. Here, we propose a Dammann vortex metasurface (DVM) for optically generating an array of diverse, diffraction-multiplexed vortex patterns, based on three custom-defined basis patterns. The proposed DVM, with its capability of quantitatively correlating phase and intensity distribution in different diffraction orders, opens up doors for various applications including orbital angular momentum encryptions and quantum entanglement.

10.
Micromachines (Basel) ; 13(7)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35888842

RESUMEN

Metasurfaces have gained growing interest in recent years due to their simplicity in manufacturing and lower insertion losses. Meanwhile, they can provide unprecedented control over the spatial distribution of transmitted and reflected optical fields in a compact form. The metasurfaces are a kind of planar array of resonant subwavelength components that, depending on the intended optical wavefronts to be sculpted, can be strictly periodic or quasi-periodic, or even aperiodic. For instance, gradient metasurfaces, a subtype of metasurfaces, are designed to exhibit spatially changing optical responses, which result in spatially varying amplitudes of scattered fields and the associated polarization of these fields. This paper starts off by presenting concepts of anomalous reflection and refraction, followed by a brief discussion on the Pancharatanm-Berry Phase (PB) and Huygens' metasurfaces. As an introduction to wavefront manipulation, we next present their key applications. These include planar metalens, cascaded meta-systems, tunable metasurfaces, spectrometer retroreflectors, vortex beams, and holography. The review concludes with a summary, preceded by a perspective outlining our expectations for potential future research work and applications.

11.
Opt Express ; 30(5): 8366-8375, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35299579

RESUMEN

As a flexible and compact nanophotonic device, the metasurface exhibits excellent potential in holographic display and optical information encryption. However, most metasurfaces are passive devices due to the limitations of fixed material properties and structural components. Magneto-optical metasurface is a hybrid device that integrates tunable functional material with elaborately designed nanostructures. It can realize dynamic modulation of the properties of light since the permittivity tensor for the magneto-optical material can be changed by applying an external magnetic field. Here, we propose a tunable metasurface composing metallic nanohole arrays with a bismuth-substituted yttrium iron garnet interleave layer and a metallic film underlayer placed on a glass substrate. The magneto-optical metasurface can achieve dynamic switchable holographic display in different polarization channels via magnetic field control based on the optical rotation of magnetic material and the complex amplitude modulation of the elaborately designed nanoholes. This feature provides a novel approach for the construction of an active tunable metasurface, which can improve the information storage capacity and security of the device. This concept is expected to be applied to various dynamic modulation fields, such as magnetically tunable lens, beam shaping, and optical information encryption.

12.
ACS Appl Mater Interfaces ; 14(4): 6230-6238, 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35044175

RESUMEN

Integrating diversified functionalities within a single aperture is crucial for microwave and optics-integrated devices. To date, research on this issue suffers from restricted bifunctionality, inadequate efficiency, and the limitation of extending to manipulate full-space wave. Here, we propose a general paradigm to achieve full-space multifunctional integration via tailoring the excited and cutoff states of spoof surface plasmon polaritons (SSPPs). A plasmonic meta-atom consisting of judiciously arranged metallic strips is used to excite and cut off the SSPP mode with uniaxially anisotropic characteristics. By shaping the topological structure of the meta-atom, the transmission and reflection phases are arbitrarily controlled at each pixel. Accordingly, the cross-placed meta-atom arrays can be designed to achieve independent phase profiles for x-/y-polarized transmission/reflection waves through dispersion engineering. A metamaterial with quadruple functionalities of backward beams scattering/anomalous reflection and electromagnetic transmission focusing/vortex is designed and fabricated as a proof-of-principle to reveal flexible manipulation. Both simulation and experimental verification are carried out in microwave frequency to demonstrate the feasibility.

13.
J Cell Physiol ; 237(3): 1923-1935, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35023144

RESUMEN

The sterile inflammation (SI) of the urinary tract is a common problem requiring serious consideration after prostatectomy. This study mainly focuses on the role of the reactive oxygen species-NLR family, pyrin domain-containing 3 (ROS-NLRP3) signaling pathway in SI after thulium laser resection of the prostate (TmLRP). Urinary cytokines were determined in patients who received TmLRP, and heat shock protein 70 (HSP70) was detected in the resected tissues. The involvement of ROS signaling in HSP70-induced inflammation was explored in THP-1 cells with or without N-acetyl- l-cysteine (NAC) pretreatment. The function of NLRP3 and Caspase-1 was determined by Western blot analysis, enzyme-linked immunosorbent assay (ELISA), and polymerase chain reaction. These phenomena and mechanisms were verified by the beagle models that received TmLRP. Clinical urine samples after TmLRP showed high expression of inflammatory factors and peaked 3-5 days after surgery. The high expression of HSP70 in the resected tissues was observed. After HSP70 stimulation, the expression of ROS, NLRP3, Caspase-1, and interleukin-18 (IL-18) increased significantly and could be reduced by ROS inhibitor NAC. The expression of IL-1ß and IL-18 could be inhibited by NLRP3 or Caspase-1 inhibitors. In beagle models that received TmLRP, HSP70, NLRP3, Caspase-1, IL-1ß, and IL-18 were highly expressed in the wound tissue or urine, and could also be reduced by NAC pretreatment. Activation of the ROS-NLRP3 signaling pathway induces SI in the wound after prostatectomy. Inhibition of this pathway may be effective for clinical prevention and treatment of SI and related complications after prostatectomy.


Asunto(s)
Inflamación , Proteína con Dominio Pirina 3 de la Familia NLR , Próstata , Especies Reactivas de Oxígeno , Acetilcisteína/farmacología , Animales , Caspasa 1/genética , Caspasa 1/metabolismo , Perros , Humanos , Inflamasomas/metabolismo , Interleucina-18 , Interleucina-1beta/metabolismo , Rayos Láser , Masculino , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Próstata/metabolismo , Próstata/cirugía , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Tulio
14.
Dis Markers ; 2021: 9141978, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34925648

RESUMEN

BACKGROUND: Hip fracture is a common occurrence in elderly populations and is frequently followed by various levels of cognitive dysfunction, leading to adverse functional outcomes. Risk stratification of hip fracture patients to identify high-risk subsets can enable improved strategies to mitigate cognitive complications. The neuropeptide galanin has multiple neurological functions, and altered levels are documented in dementia-type and depression disorders. The present study investigated the association of serum neuropeptide galanin levels in hip fracture patients with the occurrence of cognitive dysfunction during the first week of admission. METHODS: 276 hip fracture patients without preexisting delirium, cognitive impairment, or severe mental disorders were included in a cross-sectional study. Serum galanin levels were assessed by ELISA on the second day of admission. Routine clinical and laboratory variables were documented. MoCA was performed within 1 week, and those with a score < 26 were categorized with "cognitive decline." Inferential statistics including multiple linear regression analysis were applied to determine the association of serum galanin level and cognitive status. RESULTS: 141 patients were categorized with "cognitive decline," and 135 patients were categorized as "cognitively normal." Serum galanin was highly significantly increased in the "cognitive decline" group (34.2 ± 4.8, pg/ml) compared to the "cognitively normal" group (28.9 ± 3.7, pg/ml) and showed significant negative correlation with MoCA scores (r = -0.229, p = 0.016). Regression analysis showed serum galanin as the sole significant independent predictor of lower MoCA scores (ß = 0.231, p = 0.035) while age, gender, blood pressure, cholesterol, and blood glucose levels had no significant association. CONCLUSION: Higher serum galanin predicted the development of cognitive dysfunction and worse MoCA scores in a cohort of hip fracture patients without preexisting cognitive impairment or delirium at admission, thus warranting large-scale studies investigating galanin as a candidate biomarker to identify hip fracture patients at risk of cognitive decline.


Asunto(s)
Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Galanina/sangre , Fracturas de Cadera/complicaciones , Fracturas de Cadera/psicología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Disfunción Cognitiva/sangre , Estudios Transversales , Femenino , Fracturas de Cadera/sangre , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad
15.
Int Immunopharmacol ; 101(Pt A): 108267, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34740081

RESUMEN

Prostate adenocarcinoma (PRAD) is the highest incidence rate of male urogenital morbidity worldwide. Long non-coding RNAs (lncRNAs), as a significant class of gene expression regulators, play a critical role in immune regulation. The purpose of this study is to explore a new immune related lncRNA signature to exactly predict the prognosis of PRAD patients. In this study, we conducted a genome-wide comparative analysis of lncRNA expression profiles in 532 patients with PRAD from the Cancer Genome Atlas (TCGA) database. The immune-related lncRNAs were identified by Cox regression model, and then a new five immune-related lncRNAs signature (FRMD6-AS2, AC008770.3, AC109460.3, AC011899.2, and AC008063.1) were constructed, which could predict the prognosis of PRAD patients. Univariate and multivariate Cox regression analysis showed that the signature could be an independent prognostic indicator of overall survival (OS). Through further study of different clinic-pathological parameters, we found that PRAD samples can be divided into high-risk groups with shorter OS and low-risk groups with longer OS by the signature. Principal component analysis showed that five immune-related lncRNA signature could distinguish the high-risk group from low-risk group in view of the immune-related lncRNAs. The difference of immune status between the two groups was observed by gene set enrichment analysis and the ESTIMATE algorithm. Except FRMD6-AS2, the expression of the other 4 lncRNAs were remarkably up-regulated in tumor tissues. In conclusion, the identified five immune-related lncRNAs signature had important clinical significance in prognosis prediction, and can be used as potential immunotherapy targets for PRAD patients.


Asunto(s)
Adenocarcinoma/mortalidad , Biomarcadores de Tumor/metabolismo , Neoplasias de la Próstata/mortalidad , ARN Largo no Codificante/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/inmunología , Humanos , Estimación de Kaplan-Meier , Masculino , Pronóstico , Próstata/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/patología , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricos , Tasa de Supervivencia
16.
Opt Express ; 28(20): 29513-29528, 2020 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-33114850

RESUMEN

Plasmonic metamaterials enable extraordinary manipulation of key constitutive properties of light at a subwavelength scale and thus have attracted significant interest. Here, we report a simple and convenient nanofabrication method for a novel meta-device by glancing deposition of gold into anodic aluminum oxide templates on glass substrates. A methodology with the assistance of ellipsometric measurements to examine the anisotropy and optical activity properties is presented. A tunable polarization conversion in both transmission and reflection is demonstrated. Specifically, giant broadband circular dichroism for reflection at visible wavelengths is experimentally realized by oblique incidence, due to the extrinsic chirality resulting from the mutual orientation of the metamaterials and the incident beam. This work paves the way for practical applications for large-area, low-cost polarization modulators, polarization imaging, displays, and bio-sensing.

17.
ACS Nano ; 14(5): 5553-5559, 2020 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-32348122

RESUMEN

Metasurface holography has the advantage of realizing complex wavefront modulation by thin layers together with the progressive technique of computer-generated holographic imaging. Despite the well-known light parameters, such as amplitude, phase, polarization, and frequency, the orbital angular momentum (OAM) of a beam can be regarded as another degree of freedom. Here, we propose and demonstrate orbital angular momentum multiplexing at different polarization channels using a birefringent metasurface for holographic encryption. The OAM selective holographic information can only be reconstructed with the exact topological charge and a specific polarization state. By using an incident beam with different topological charges as erasers, we mimic a super-resolution case for the reconstructed image, in analogy to the well-known STED technique in microscopy. The combination of multiple polarization channels together with the orbital angular momentum selectivity provides a higher security level for holographic encryption. Such a technique can be applied for beam shaping, optical camouflage, data storage, and dynamic displays.

18.
J Cell Mol Med ; 23(10): 6578-6594, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31449345

RESUMEN

Quaking homolog (QKI) is a member of the RNA-binding signal transduction and activator of proteins family. Previous studies showed that QKI possesses the tumour suppressor activity in human cancers by interacting with the 3'-untraslated region (3'-UTR) of various gene transcripts via the STAR domain. This study first assessed the association of QKI-6 expression with clinicopathological and survival data from bladder cancer patients and then investigated the underlying molecular mechanisms. Bladder cancer tissues (n = 223) were subjected to immunohistochemistry, and tumour cell lines and nude mice were used for different in vitro and in vivo assays following QKI-6 overexpression or knockdown. QKI-6 down-regulation was associated with advanced tumour TNM stages and poor patient overall survival. QKI-6 overexpression inhibited bladder cancer cell growth and invasion capacity, but induced tumour cell apoptosis and cell cycle arrest. Furthermore, ectopic expression of QKI-6 reduced tumour xenograft growth and expression of proliferation markers, Ki67 and PCNA. However, knockdown of QKI-6 expression had opposite effects in vitro and in vivo. QKI-6 inhibited expression of E2 transcription factor 3 (E2F3) by directly binding to the E2F3 3'-UTR, whereas E2F3 induced QKI-6 transcription by binding to the QKI-6 promoter in negative feedback mechanism. QKI-6 expression also suppressed activity and expression of nuclear factor-κB (NF-κB) signalling proteins in vitro, implying a novel multilevel regulatory network downstream of QKI-6. In conclusion, QKI-6 down-regulation contributes to bladder cancer development and progression.


Asunto(s)
Factor de Transcripción E2F3/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , FN-kappa B/metabolismo , Proteínas de Unión al ARN/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Regiones no Traducidas 3' , Animales , Apoptosis/genética , Puntos de Control del Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación hacia Abajo , Factor de Transcripción E2F3/genética , Femenino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , FN-kappa B/antagonistas & inhibidores , Estadificación de Neoplasias , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas de Unión al ARN/genética , Transducción de Señal/genética , Trasplante Heterólogo , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/patología
19.
Nano Lett ; 19(9): 6585-6591, 2019 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-31405278

RESUMEN

Nonlinear wavefront control is a crucial requirement in realizing nonlinear optical applications with metasurfaces. Numerous aspects of nonlinear frequency conversion and wavefront control have been demonstrated for plasmonic metasurfaces. However, several disadvantages limit their applicability in nonlinear nanophotonics, including high dissipative loss and low optical damage threshold. In contrast, it has been shown that metasurfaces made of high-index dielectrics can provide strong nonlinear responses. Regardless of the recent progress in nonlinear optical processes using all-dielectric nanostructures and metasurfaces, much less advancement has been made in realizing a full wavefront control directly with the generation process. Here, we demonstrate the nonlinear wavefront control for the third-harmonic generation with a silicon metasurface. We use a Pancharatnam-Berry phase approach to encode phase gradients and holographic images on nanostructured silicon metasurfaces. We experimentally demonstrate the polarization-dependent wavefront control and the reconstruction of an encoded hologram at the third-harmonic wavelength with high fidelity. Further, we show that holographic multiplexing is possible by utilizing the polarization states of the third harmonic generation. Our approach eases design and fabrication processes and paves the way to an easy to use toolbox for nonlinear optical wavefront control with all-dielectric metasurfaces.

20.
Opt Express ; 27(13): 18740-18750, 2019 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-31252811

RESUMEN

Designing reconfigurable metasurfaces that can dynamically control scattered electromagnetic waves and work in the near-infrared (NIR) and optical regimes remains a challenging task, which is hindered by the static material property and fixed structures. Phase change materials (PCMs) can provide high contrast optical refractive indexes at high frequencies between amorphous and crystal states, therefore are promising as feasible materials for reconfigurable metasurfaces. Here, we propose a hybrid metasurface that can arbitrarily modulate the complex amplitude of incident light with uniform amplitude and full 2π phase coverage by utilizing composite concentric rings (CCRs) with different ratios of gold and PCMs. Our designed metasurface possesses a bi-functionality that is capable of splitting beams or generating vortex beams by thermal switching between metal and semiconductor states of vanadium oxide (VO2), respectively. It can be easily integrated into low loss photonic circuits with an ultra-small footprint. Our metadevice serves as a novel paradigm for active control of beams, which may open new opportunities for signal processing, memory storage, holography, and anti-counterfeiting.

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