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1.
Natl Sci Rev ; 11(6): nwae137, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38770530

RESUMEN

Exploring Hidden Dimensions: Unveiling Topological Crystals in a 4D Space.

2.
Life Sci ; 348: 122677, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38702026

RESUMEN

AIMS: Epidemiological evidence indicates that there is a substantial association between body mass index (BMI) and at least ten forms of cancer, including melanoma, and BMI imbalance contributes to the poor survival rate of cancer patients before and after therapy. Nevertheless, few pharmacological studies on models of obesity and cancer have been reported. In this study, we administered epigallocatechin gallate (EGCG) to B16BL6 tumor-bearing mice that received a high-fat diet (HFD) to examine its impact. METHODS: B16BL6 tumor-bearing mice were fed a HFD. Body weight and food intake were documented every week. We conducted a Western blot analysis to examine the protein levels in the tumor, gastrocnemius (GAS), and tibialis anterior (TA) muscles, as well as the inguinal and epididymal white adipose tissues (iWAT and eWAT). KEY FINDINGS: EGCG has been shown to have anti-cancer effects equivalent to those of cisplatin, a chemotherapy drug. Furthermore, EGCG protected against the loss of epidydimal white adipose tissue by regulating protein levels of lipolysis factors of adipose triglyceride lipase and hormone-sensitive lipase as well as WAT browning factors of uncoupling protein 1, as opposed to cisplatin. EGCG was shown to reduce the protein levels of muscular atrophy factors of muscle RING-finger protein-1, whereas cisplatin did not contribute to rescuing the atrophy of TA and GAS muscles. CONCLUSION: Taken together, our findings indicate that EGCG has a preventive effect against cachexia symptoms and has anti-cancer effects similar to those of cisplatin in tumor-bearing mice fed a high-fat diet.


Asunto(s)
Catequina , Dieta Alta en Grasa , Melanoma Experimental , Ratones Endogámicos C57BL , Atrofia Muscular , Animales , Catequina/análogos & derivados , Catequina/farmacología , Catequina/uso terapéutico , Dieta Alta en Grasa/efectos adversos , Ratones , Masculino , Atrofia Muscular/prevención & control , Atrofia Muscular/metabolismo , Atrofia Muscular/tratamiento farmacológico , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Obesidad/metabolismo , Obesidad/tratamiento farmacológico , Músculo Esquelético/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/patología
3.
Int J Mol Sci ; 24(24)2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38139419

RESUMEN

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide, and despite advances in treatment, survival rates are still low; therefore, the development of novel drugs is imperative. Acetylcorynoline (ACN) is derived from Corydalis ambigua Cham. et Schltdl tubers. The effect of ACN on colon cancer is still unknown. Therefore, we investigated its potential effects. Our data showed that ACN inhibited cell viability and proliferation. Moreover, ACN induced apoptosis and cell cycle arrest by inhibiting cell growth. In the present study, we hypothesized that ACN regulates c-Myc through CNOT2 or MID1IP1. ACN reduced the protein expression of oncogenic genes, decreased c-Myc half-life, and rapidly inhibited the serum stimulation response. Moreover, knockdown of CNOT2 and MID1IP1 with ACN increased apoptosis and further reduced the expression of oncogenes. In addition, ACN exhibited a synergistic effect with low-dose 5-fluorouracil (5-FU) and doxorubicin (Dox). Collectively, our data demonstrate that ACN inhibited c-Myc expression through CNOT2 and MID1IP1, and induced apoptosis. These findings indicate the potential of ACN as a therapeutic agent against colon cancer.


Asunto(s)
Neoplasias del Colon , Transducción de Señal , Humanos , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Puntos de Control del Ciclo Celular , Apoptosis , Fluorouracilo/farmacología , Mitosis , Proliferación Celular , Línea Celular Tumoral , Proteínas Represoras/genética
4.
Sci Adv ; 9(19): eadf3510, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37172089

RESUMEN

The concept of non-Hermitian physics, originally developed in the context of quantum field theory, has been investigated on distinct photonic platforms and created a plethora of counterintuitive phenomena. Interfacing non-Hermitian photonics and nanoplasmonics, here, we demonstrate unidirectional excitation and reflection of surface plasmon polaritons by elaborately designing the permittivity profile of non-Hermitian metagratings, in which the eigenstates of the system can coalesce at an exceptional point. Continuous tuning of the excitation or reflection ratios is also possible through altering the geometry of the metagrating. The controllable directionality and robust performance are attributed to the phase transition near the exceptional point, which is fully confirmed by the theoretic calculation, numerical simulation, and experimental characterization. Our work pushes non-Hermitian photonics to the nanoscale regime and paves the way toward high-performance plasmonic devices with superior controllability, performance, and robustness by using the topological effect associated with non-Hermitian systems.

5.
Light Sci Appl ; 12(1): 68, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36882418

RESUMEN

A single-step printable platform for ultraviolet (UV) metasurfaces is introduced to overcome both the scarcity of low-loss UV materials and manufacturing limitations of high cost and low throughput. By dispersing zirconium dioxide (ZrO2) nanoparticles in a UV-curable resin, ZrO2 nanoparticle-embedded-resin (nano-PER) is developed as a printable material which has a high refractive index and low extinction coefficient from near-UV to deep-UV. In ZrO2 nano-PER, the UV-curable resin enables direct pattern transfer and ZrO2 nanoparticles increase the refractive index of the composite while maintaining a large bandgap. With this concept, UV metasurfaces can be fabricated in a single step by nanoimprint lithography. As a proof of concept, UV metaholograms operating in near-UV and deep-UV are experimentally demonstrated with vivid and clear holographic images. The proposed method enables repeat and rapid manufacturing of UV metasurfaces, and thus will bring UV metasurfaces more close to real life.

6.
Nat Mater ; 22(4): 474-481, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36959502

RESUMEN

Metalenses are attractive alternatives to conventional bulky refractive lenses owing to their superior light-modulating performance and sub-micrometre-scale thicknesses; however, limitations in existing fabrication techniques, including high cost, low throughput and small patterning area, have hindered their mass production. Here we demonstrate low-cost and high-throughput mass production of large-aperture visible metalenses using deep-ultraviolet argon fluoride immersion lithography and wafer-scale nanoimprint lithography. Once a 12″ master stamp is imprinted, hundreds of centimetre-scale metalenses can be fabricated using a thinly coated high-index film to enhance light confinement, resulting in a substantial increase in conversion efficiency. As a proof of concept, an ultrathin virtual reality device created with the printed metalens demonstrates its potential towards the scalable manufacturing of metaphotonic devices.

7.
Nano Lett ; 23(4): 1195-1201, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36622968

RESUMEN

Metasurfaces have shown remarkable potential to manipulate many of light's intrinsic properties, such as phase, amplitude, and polarization. Recent advancements in nanofabrication technologies and persistent efforts from the research community result in the realization of highly efficient, broadband, and multifunctional metasurfaces. Simultaneous control of these characteristics in a single-layered metasurface will be an apparent technological extension. Here, we demonstrate a broadband multifunctional metasurface platform with the unprecedented ability to independently control the phase profile for two orthogonal polarization states of incident light over dual-wavelength spectra (ultraviolet to visible). In this work, multiple single-layered metasurfaces composed of bandgap-engineered silicon nitride nanoantennas are designed, fabricated, and optically characterized to demonstrate broadband multifunctional light manipulation ability, including structured beam generation and meta-interferometer implementation. We envision the presented metasurface platform opening new avenues for broadband multifunctional applications including ultraviolet-visible spectroscopy, spatially modulated illumination microscopy, optical data storage, and information encoding.

8.
Adv Mater ; 35(4): e2203889, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35861661

RESUMEN

Low-dimensional light-emitting materials have been actively investigated due to their unprecedented optical and optoelectronic properties that are not observed in their bulk forms. However, the emission from low-dimensional light-emitting materials is generally weak and difficult to use in nanophotonic devices without being amplified and engineered by optical cavities. Along with studies on various planar optical cavities over the last decade, the physics of cavity-emitter interactions as well as various integration methods are investigated deeply. These integrations not only enhance the light-matter interaction of the emitters, but also provide opportunities for realizing nanophotonic devices based on the new physics allowed by low-dimensional emitters. In this review, the fundamentals, strengths and weaknesses of various planar optical resonators are first provided. Then, commonly used low-dimensional light-emitting materials such as 0D emitters (quantum dots and upconversion nanoparticles) and 2D emitters (transition-metal dichalcogenide and hexagonal boron nitride) are discussed. The integration of these emitters and cavities and the expect interplay between them are explained in the following chapters. Finally, a comprehensive discussion and outlook of nanoscale cavity-emitter integrated systems is provided.

9.
Nat Commun ; 13(1): 5920, 2022 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-36216802

RESUMEN

Structured light (SL)-based depth-sensing technology illuminates the objects with an array of dots, and backscattered light is monitored to extract three-dimensional information. Conventionally, diffractive optical elements have been used to form laser dot array, however, the field-of-view (FOV) and diffraction efficiency are limited due to their micron-scale pixel size. Here, we propose a metasurface-enhanced SL-based depth-sensing platform that scatters high-density ~10 K dot array over the 180° FOV by manipulating light at subwavelength-scale. As a proof-of-concept, we place face masks one on the beam axis and the other 50° apart from axis within distance of 1 m and estimate the depth information using a stereo matching algorithm. Furthermore, we demonstrate the replication of the metasurface using the nanoparticle-embedded-resin (nano-PER) imprinting method which enables high-throughput manufacturing of the metasurfaces on any arbitrary substrates. Such a full-space diffractive metasurface may afford ultra-compact depth perception platform for face recognition and automotive robot vision applications.


Asunto(s)
Imagenología Tridimensional , Proyectos de Investigación
10.
Diagnostics (Basel) ; 12(9)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36140491

RESUMEN

Diffusion tensor imaging (DTI) and magnetization transfer (MT) magnetic resonance imaging (MRI) can help detect spinal cord pathology, and tract-specific analysis of their parameters, such as fractional anisotropy (FA), mean diffusivity, axial diffusivity (AD), radial diffusivity (RD) and MT ratio (MTR), can give microstructural information. We performed the tract-based acquisition of MR parameters of three major motor tracts: the lateral corticospinal (CS), rubrospinal (RuS) tract, and lateral reticulospinal (RS) tract as well as two major sensory tracts, i.e., the fasciculus cuneatus (FC) and spinal lemniscus, to detect pathologic change and find correlations with clinical items. MR parameters were extracted for each tract at three levels: the most compressed lesion level and above and below the lesion. We compared the MR parameters of eight cervical spondylotic myelopathy patients and 12 normal controls and analyzed the correlation between clinical evaluation items and MR parameters in patients. RuS and lateral RS showed worse DTI parameters at the lesion level in patients compared to the controls. Worse DTI parameters in those tracts were correlated with weaker power grasp at the lesion level. FC and lateral CS showed a correlation between higher RD and lower FA and MTR with a weaker lateral pinch below the lesion level.

11.
Nanoscale ; 14(12): 4380-4410, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35266481

RESUMEN

The holographic display, one of the most realistic ways to reconstruct optical images in three-dimensional (3D) space, has gained a lot of attention as a next-generation display platform for providing deeper immersive experiences to users. So far, diffractive optical elements (DOEs) and spatial light modulators (SLMs) have been used to generate holographic images by modulating electromagnetic waves at each pixel. However, such architectures suffer from limitations in terms of having a resolution of only a few microns and the bulkiness of the entire optical system. In this review, we describe novel metasurfaces-based nanophotonic platforms that have shown exceptional control of electromagnetic waves at the subwavelength scale as promising candidates to overcome existing restrictions, while realizing flat optical devices. After introducing the fundamentals of metasurfaces in terms of spatial and spectral wavefront modulation, we present a variety of multiplexing approaches for high-capacity and full-color metaholograms exploiting the multiple properties of light as an information carrier. We then review tunable metaholograms using active materials modulated by several external stimuli. Afterward, we discuss the integration of metasurfaces with other optical elements required for future 3D display platforms in augmented/virtual reality (AR/VR) displays such as lenses, beam splitters, diffusers, and eye-tracking sensors. Finally, we address the challenges of conventional nanofabrication methods and introduce scalable preparation techniques that can be applied to metasurface-based nanophotonic technologies towards commercially and ergonomically viable future holographic displays.

12.
ACS Omega ; 4(7): 11724-11727, 2019 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-31460278

RESUMEN

We used a cesium hexafluorophosphate (CsPF6)-containing liquid electrolyte for surface-patterned Li metal anodes and confirmed that there is a synergistic improvement in the electrochemical performance such as cycle performance and rate capability. For instance, the surface-patterned Li metal maintains 91.4% of the initial discharge capacity after the 1000th cycle (C/2 = 0.8 mA cm-2 for charging, 1C for discharging). When a large quantity of the CsPF6-containing liquid electrolyte (600 µL) is used, the bare Li metal and surface-patterned Li metal are more effectively stabilized in comparison with the case where 80 µL of electrolyte is used, resulting in improved electrochemical performance. Through systematic testing, we recognize that these results are because of the self-healing electrostatic shield mechanism, which is mainly dependent on the amount of Cs+ ions. A small amount of Cs+ ions cannot effectively counteract the incoming Li+ ions because they cannot form an effective electrostatic shield on the protrusions present on the Li metal surface.

13.
ACS Appl Mater Interfaces ; 11(35): 31777-31785, 2019 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-31403273

RESUMEN

We present a synergistic strategy to boost the cycling performance of Li-metal batteries. The strategy is based on the combined use of a micropattern (MP) on the surface of the Li-metal electrode and an advanced dual-salt electrolyte (DSE) system to more efficiently control undesired Li-metal deposition at higher current density (∼3 mA cm-2). The MP-Li electrode induces a spatially uniform current distribution to achieve dendrite-free Li-metal deposition beneath the surface layer formed by the DSE. The MP-Li/DSE combination exhibited excellent synergistic rate capability improvements that were neither observed with the MP-Li system nor for the bare Li/DSE system. The combination also resulted in the Li||LiMn2O4 battery attaining over 1 000 cycles, which is twice as long at the same capacity retention (80%) compared with the control cells (MP-Li without DSE). We further demonstrated extremely fast charging at a rate of 15 C (19.5 mA cm-2).

14.
Clin Interv Aging ; 12: 1835-1842, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29138544

RESUMEN

PURPOSE: Postoperative delirium is a risk factor for worse outcome after hip fracture surgery in elderly patients. Postoperative delirium is associated with anesthesia, postoperative pain, and patient factors. We investigated the incidence, predictors, and prognostic implications of post-operative delirium after hemiarthroplasty (HA) in elderly patients with femoral neck fracture. PATIENTS AND METHODS: A total of 356 consecutive patients aged >70 years who underwent HA for femoral neck fracture were enrolled. Diagnosis of delirium was made by a psychiatrist based on patient status and an objective scoring system. The patients were divided into 2 categories according to the HA onset time (immediate [≤24 h after surgery] vs delayed delirium [>24 h after surgery]) and its incidence, predictors and mortality were evaluated. RESULTS: Postoperative delirium was diagnosed in 110 patients (30.9%) during hospitalization. Immediate and delayed delirium occurred in 59 (53.6%), and 51 (46.4%) patients, respectively. The independent predictors of immediate delirium included age (odds ratio [OR] 1.47, 95% CI 0.98-2.23, p=0.066), and general anesthesia (OR 2.25, 95% CI 1.17-4.43, p=0.015). The independent predictors of delayed delirium were parkinsonism (OR 5.75, 95% CI 1.66-19.96, p=0.006), intensive care unit stay (OR 1.85, 95% CI 0.97-3.56, p=0.064), and higher American Society of Anesthesiologists grade (OR 2.33, 95% CI 0.90-6.07, p=0.083). On Kaplan-Meier survival analysis, the 2-year survival rate was significantly lower in the immediate delirium group than those in the delayed and control groups (71.0% vs 83.6% vs 87.8%, respectively; p=0.031). CONCLUSION: Immediate and delayed delirium after HA for femoral neck fracture had different predictors and immediate delirium was associated with worse prognosis.


Asunto(s)
Delirio/epidemiología , Fracturas del Cuello Femoral/cirugía , Hemiartroplastia/efectos adversos , Complicaciones Posoperatorias/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Anestesia General/estadística & datos numéricos , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Incidencia , Estimación de Kaplan-Meier , Masculino , Oportunidad Relativa , Pronóstico , Factores de Riesgo
15.
J Back Musculoskelet Rehabil ; 30(4): 801-809, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28372312

RESUMEN

BACKGROUND: Posterior lumbar surgery can lead to damage on paraspinal muscles. OBJECTIVE: Our study aimed to examine the recovery in the denervated paraspinal muscles by posterior lumbar surgery and to determine that of improvement in the lower back pain (LBP). METHODS: Depending on surgical treatments, the patients were divided into two groups: The group I (interspinous implantation with decompression) and II (posterior lumbar interbody fusion with decompression). The paraspinal mapping score was recorded for individual muscle. RESULTS: In the group I, there was reinnervation in the denervated multifidus and erector spinae at the upper, surgical and lower levels at 12 months. In the group II, there was reinnervation in the denervated erector spinae at the upper, surgical and lower levels at 12 months. There was significant aggravation in the LBP in both groups at immediate postoperative. But there was significant improvement in it at 6 months in the group I and at 12 months in the group II. CONCLUSION: There was reinnervation in not only denervated multifidus and erector spinae at 12 months following interspinous ligament stabilization but also in denervated erector spinae at 12 months following pedicle screw fixation with fusion.


Asunto(s)
Descompresión Quirúrgica/efectos adversos , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares/cirugía , Regeneración Nerviosa , Músculos Paraespinales/fisiología , Fusión Vertebral/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Electromiografía , Femenino , Humanos , Región Lumbosacra , Masculino , Persona de Mediana Edad , Músculos Paraespinales/lesiones , Músculos Paraespinales/inervación , Recuperación de la Función , Adulto Joven
16.
ACS Appl Mater Interfaces ; 9(7): 6000-6006, 2017 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-28121126

RESUMEN

Owing to the natural abundance of sodium resources and their low price, next-generation batteries employing an Na metal anode, such as Na-O2 and Na-S systems, have attracted a great deal of interest. However, the poor reversibility of an Na metal electrode during repeated electrochemical plating and stripping is a major obstacle to realizing rechargeable sodium metal batteries. It mainly originates from Na dendrite formation and exhaustive electrolyte decomposition due to the high reactivity of Na metal. Herein, we report a free-standing composite protective layer (FCPL) for enhancing the reversibility of an Na metal electrode by mechanically suppressing Na dendritic growth and mitigating the electrolyte decomposition. A systematic variation of the liquid electrolyte uptake of FCPL verifies the existence of a critical shear modulus for suppressing Na dendrite growth, being in good agreement with a linear elastic theory, and emphasizes the importance of the ionic conductivity of FCPL for attaining uniform Na plating and stripping. The Na-Na symmetric cell with an optimized FCPL exhibits a cycle life two times longer than that of a bare Na electrode.

17.
Injury ; 46(6): 1174-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25624271

RESUMEN

Minimally invasive plate osteosynthesis (MIPO) using a locking plate has been widely used for distal femur fractures in the elderly with osteoporosis and yielded favourable results. However, implant failure and subsequent periplate fracture have still occurred owing to the controversy of concepts regarding locked plating. The treatment after failed MIPO in elderly patients is very challenging and has been not yet addressed definitely in the literature, although several options can be considered. We report the successful outcomes of two cases treated with overlapping intramedullary (IM) nailing for implant failure and periplate fracture after MIPO for osteoporotic distal femur fracture, along with simple tips of distal interlocking of IM nail.


Asunto(s)
Clavos Ortopédicos , Placas Óseas , Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas , Fracturas Osteoporóticas/cirugía , Anciano , Fenómenos Biomecánicos , Femenino , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/patología , Fijación Intramedular de Fracturas/métodos , Curación de Fractura , Humanos , Procedimientos Quirúrgicos Mínimamente Invasivos , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/patología , Radiografía , Rango del Movimiento Articular , Resultado del Tratamiento
18.
Asian Spine J ; 7(4): 301-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24353847

RESUMEN

STUDY DESIGN: A nation-wide, outpatient-based, cross-sectional survey with the use of questionnaires. PURPOSE: To evaluate the pain, disability and satisfaction of patients with osteoporotic vertebral compression fractures (OVCFs). OVERVIEW OF LITERATURE: There are no nation-wide data in Korea on the degree of pain, disability and satisfaction with treatment in patients with OVCFs. METHODS: We performed a cross-sectional survey of 573 patients with OVCFs. After excluding incomplete questionnaires (missing more than 30% of the variables), 430 patient-physician-matched data sets were collected for this survey. RESULTS: Patients with OVCFs were managed with conservative treatment in 63% and with a vertebroplasty in 37%. The means of the latest visual analogue scale (VAS, 5.2) and Oswestry Disability Index (ODI, 47.7) scores checked at the time of survey were significantly higher than those VAS and ODI scores prior to OVCFs (the prefracture VAS and ODI scores, 3.6 and 26.3, respectively; p<0.001 for both comparisons). However, the means of the latest VAS and ODI scores were insignificantly different between the conservative and vertebroplasty groups, irrespective of the duration from the fractures. Overall, 75% of patients were satisfied with their clinical outcomes. However, the percentages of patient's satisfaction were not significantly different between the conservative and vertebroplasty groups. Eighty-eight percent of patients felt some or marked deterioration of their general health condition following OVCFs. CONCLUSIONS: These results indicate that although most patients with OVCFs were satisfied with their clinical outcomes, their subjective general health conditions, as well as their pain and disability, did not recover to the prefracture state.

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