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1.
ACS Nano ; 18(34): 23403-23411, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39088760

RESUMEN

The exponential growth of data in the big data era has made it imperative to improve the data storage density and calculation speed. Therefore, the development of a multibit memory with an ultrafast operational speed is of great significance. In this work, a floating-gate (FG) memory based on the ReS2/h-BN/graphene van der Waals heterostructure is reported. The device exhibits ultrafast and multilevel nonvolatile memory characteristics, notably featuring an exceptionally large memory window of 113.36 V, a substantial erasing/programming current ratio of 107, an ultrafast operational speed of 30 ns, outstanding endurance exceeding 1000 cycles, and retention performance exceeding 1100 s. Furthermore, the device exhibits both electrically and optically tunable multilevel nonvolatile memory behavior. By controlling the voltage and light pulse parameters, the device achieves an electrical memory state of 130 levels (>7 bits) and an optical memory state of 45 levels (>5 bits).

2.
Mol Plant ; 13(3): 398-413, 2020 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-31953223

RESUMEN

Plant and non-plant species possess cryptochrome (CRY) photoreceptors to mediate blue light regulation of development or the circadian clock. The blue light-dependent homooligomerization of Arabidopsis CRY2 is a known early photoreaction necessary for its functions, but the photobiochemistry and function of light-dependent homooligomerization and heterooligomerization of cryptochromes, collectively referred to as CRY photooligomerization, have not been well established. Here, we show that photooligomerization is an evolutionarily conserved photoreaction characteristic of CRY photoreceptors in plants and some non-plant species. Our analyses of the kinetics of the forward and reverse reactions of photooligomerization of Arabidopsis CRY1 and CRY2 provide a previously unrecognized mechanism underlying the different photosensitivity and photoreactivity of these two closely related photoreceptors. We found that photooligomerization is necessary but not sufficient for the functions of CRY2, implying that CRY photooligomerization is presumably accompanied by additional function-empowering conformational changes. We further demonstrated that the CRY2-CRY1 heterooligomerization plays roles in regulating functions of Arabidopsis CRYs in vivo. Taken together, these results suggest that photooligomerization is an evolutionarily conserved mechanism determining the photosensitivity and photoreactivity of plant CRYs.


Asunto(s)
Arabidopsis/metabolismo , Arabidopsis/efectos de la radiación , Criptocromos/química , Criptocromos/metabolismo , Luz , Multimerización de Proteína/efectos de la radiación , Oscuridad , Células HEK293 , Humanos , Estructura Cuaternaria de Proteína
3.
Med Sci Monit ; 24: 7603-7613, 2018 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-30356034

RESUMEN

BACKGROUND Extranodal NK/T cell lymphoma, nasal type (ENKTL-NT) is difficult to distinguish from nasal polyps and inverted papilloma, leading to its high misdiagnosis ratio. The aim of this study was to investigate its potential prognostic indicators. MATERIAL AND METHODS Kaplan-Meier method was used to calculate overall survival (OS) rate. Cox proportional hazards regression was used to analyze risk ratios (ORs) with 95% confidence intervals (CIs). RESULTS Nasal ala infiltration and nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm were potential prognostic factors for OS (p=0.0323 and 0.0072, respectively). Cox proportional-hazards regression indicated that high LMP1 expression and the nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm were the independent risk factors for poor OS of ENKTL-NT (HR=3.0655, p=0.028; HR=2.3650, p=0.0452, respectively). In the subgroup analysis, the OS rate was lower when the nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm in the patients who had high expression of LMP1 (p=0.0651), whereas high LMP1 expression increased the risk of worse prognostic outcome in patients with deep infiltration thickness. Thus, high LMP1 expression may contribute to the tissue invasion of ENKTL-NT. CONCLUSIONS Any patient with nasal ala soft-tissue invasion, nasal floor thickness >2.0 mm/nasal septum thickness >2.5 mm on CT imaging or high LMP1 expression should prompt immediate histopathologic diagnosis to rule out ENKTL-NT in clinical practice.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Proteínas del Citoesqueleto/biosíntesis , Proteínas con Dominio LIM/biosíntesis , Linfoma Extranodal de Células NK-T/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adulto , Anciano , Biomarcadores de Tumor/biosíntesis , Biomarcadores de Tumor/genética , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Femenino , Humanos , Estimación de Kaplan-Meier , Proteínas con Dominio LIM/genética , Proteínas con Dominio LIM/metabolismo , Linfoma Extranodal de Células NK-T/diagnóstico , Linfoma Extranodal de Células NK-T/genética , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
4.
Cancer Biomark ; 18(4): 367-374, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28106540

RESUMEN

BACKGROUND: Breast cancer is one of the most common type of female cancer worldwide and represents 14% of cancer-related deaths in women. Early detection is the most important factor for treatment and prognosis of breast cancer. In most countries, the women are currently screened with mammography only. Even though there has been considerable progress in the detection, surgical therapy, hormonal and target therapy of breast cancer, there are about ∼ 3500 000 women who die from breast cancer each year. Therefore, there is an urgent need to explore the new techniques for early detection of breast cancer. Magnetic resonance imaging (MRI) has the potential to improve breast cancer detection at an early stage because of its higher sensitivity. Glucose transporter (Glut) is a cellular transmembrane receptor that plays key roles in cell glucose metabolism and over-expressed in breast cancer cells. 2-deoxy-D-glucose having a similar structure to D-glucose can specifically interact with Glut. METHODS: In the present study, we constructed a 2-deoxy-D-glucose-functionalized superparamagnetic iron oxide (SPIO) nanoparticles that coated with meso-2,3-dimercaptosuccinic acid (γ-Fe2O3@DMSA-DG NPs). The aim of this study is to evaluate the efficacy of new constructed MRI contrast agent (γ-Fe2O3@DMSA-DG NPs) in detecting human breast cancers. RESULTS: Our results showed that breast cancer cells MDA-MD-231, MCF7 and ZR-75-1 had a high uptake rate of γ-Fe2O3@DMSA-DG NPs than human breast fibroblast cell HUM-CELL-0056. There was a significant difference of T2 relaxation times and signal intensity between breast cancer cells and human breast fibroblast cells labeled with γ-Fe2O3@DMSA-DG NPs when MIR. CONCLUSION: Our results indicated that γ-Fe2O3@DMSA-DG NPs may be used as a new MRI contrast agent for detection of breast cancer.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Rastreo Celular/métodos , Detección Precoz del Cáncer , Nanopartículas de Magnetita/administración & dosificación , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Desoxiglucosa/administración & dosificación , Desoxiglucosa/química , Femenino , Compuestos Férricos/administración & dosificación , Compuestos Férricos/química , Fibroblastos/metabolismo , Humanos , Células MCF-7 , Imagen por Resonancia Magnética , Nanopartículas de Magnetita/química , Succímero/química
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