Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
HLA ; 102(6): 756-758, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37702112

RESUMEN

HLA-B*15:270 differs from HLA-B*15:12:01 by one nucleotide substitution at position 679 in exon 4.


Asunto(s)
Antígenos HLA-B , Nucleótidos , Humanos , Alelos , Secuencia de Bases , Antígenos HLA-B/genética , Exones/genética , Análisis de Secuencia de ADN
2.
Sensors (Basel) ; 23(12)2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37420534

RESUMEN

Studying the nonlinear photoresponse of different materials, including III-V semiconductors, two-dimensional materials and many others, is attracting burgeoning interest in the terahertz (THz) field. Especially, developing field-effect transistor (FET)-based THz detectors with preferred nonlinear plasma-wave mechanisms in terms of high sensitivity, compactness and low cost is a high priority for advancing performance imaging or communication systems in daily life. However, as THz detectors continue to shrink in size, the impact of the hot-electron effect on device performance is impossible to ignore, and the physical process of THz conversion remains elusive. To reveal the underlying microscopic mechanisms, we have implemented drift-diffusion/hydrodynamic models via a self-consistent finite-element solution to understand the dynamics of carriers at the channel and the device structure dependence. By considering the hot-electron effect and doping dependence in our model, the competitive behavior between the nonlinear rectification and hot electron-induced photothermoelectric effect is clearly presented, and it is found that the optimized source doping concentrations can be utilized to reduce the hot-electron effect on the devices. Our results not only provide guidance for further device optimization but can also be extended to other novel electronic systems for studying THz nonlinear rectification.


Asunto(s)
Semiconductores , Radiación Terahertz , Diseño de Equipo , Electrones
3.
ISA Trans ; 131: 137-145, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35606194

RESUMEN

This paper focuses on the problem of stability analysis for Riemann-Liouville nabla fractional order systems. On one hand, a useful comparison principle is built and then a rigorous proof is constructed for the well-known Lyapunov stability criterion in terms of class K functions. On the other hand, the constraint of the Lyapunov function is refined using a positive constant γ4 or a sequence h(k), resulting two practical theorems. Finally, three illustrative examples are given to show the applicability of the proposed method.


Asunto(s)
Redes Neurales de la Computación , Registros , Rayos gamma
4.
ISA Trans ; 131: 83-94, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35537872

RESUMEN

In this paper, we provide a framework to achieve interval estimation for nabla Caputo fractional order linear time-invariant (LTI) systems in the presence of bounded model uncertainties. Interval observers based on fractional order positive systems theory are designed by possessing desired stable and positive error dynamics. Specifically, the basic concepts and conditions for guaranteeing stability and positivity of the considered systems are derived systematically by finding the system responses. Using the developed criteria and the structure of Luenberger-type observers, a classic interval observer is designed directly which further extends the system classes of interval estimation. Besides, due to the possible absence of a gain matrix which ensures positivity requirement, a more general interval observer design scheme is given by exploiting the coordinate transformation technique. Finally, some simulated cases including fault detection and fractional order circuits related scenarios are developed to validate the usefulness and practicality of the framework.


Asunto(s)
Registros , Teoría de Sistemas , Incertidumbre
5.
Front Med (Lausanne) ; 8: 737713, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34722577

RESUMEN

Antipsychotic-related constipation (APRC) is one of the most common side effects of taking antipsychotic medication. APRC can seriously impact patient quality of life and is potentially fatal, though the efficacy of current APRC treatments is low for most patients. In this study, we conducted a controlled, pilot randomized, sham-electroacupuncture (SEA) study to assess the efficacy of electroacupuncture (EA) in patients with APRC. We used 16S rRNA gene sequencing to assess the microbial profiles of these patients and analyze how EA treatments affected their bacteria. Methods: We treated 133 APRC patients with randomly assigned EA treatments or SEA treatments for 4 consecutive weeks, fully evaluating the patients 8 weeks after treatment. The participants, outcome assessors, and statistics were all blind to the EA and SEA treatments. Outcomes assessed included changes in spontaneous bowel movements (SBMs) and the frequency of rescue measures. We detected assessed the microbial diversity of stool specimens both before and after EA treatment using 16S rRNA gene sequencing. Results: Both EA and SEA treatments reduced the need for constipation rescue measures and did not have serious side effects. EA treatments were better than SEA treatments at increasing SBMs and reducing rescue measures. The diversity of gut microbiota changed after EA treatment. LEfSe analysis indicated changes in the genus (belonging to phylum Proteobacteria) of gut microbiota in patients following EA treatment. Conclusions: This study found that EA treatment is effective and safe for patients with APRC, and could be associated with changes in their microbial profiles. Further study, with larger sample sizes, is needed to explore the efficacy of EA intervention as a clinical treatment for APRC. Trial Registration: ChiCTR, ChiCTR-ONC-17010842, http://www.chictr.org.cn/showproj.aspx?proj=18420.

6.
ChemMedChem ; 9(3): 627-37, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24285590

RESUMEN

The histone deacetylase (HDAC) family is a promising drug target class owing to the importance of these enzymes in a variety of cellular processes. Docking studies were conducted to identify novel HDAC inhibitors. Subtle modifications in the recognition domain were introduced into a series of chlamydocin analogues, and the resulting scaffolds were combined with various zinc binding domains. Remarkably, cyclo(L-Asu(NHOH)-L-A3mc6c-L-Phe-D-Pro, compound 1 b), with a methyl group at positions 3 or 5 on the aliphatic ring, exhibited better antiproliferative effects than trichostatin A (TSA) against MCF-7 and K562 cell lines. In addition to cell-cycle arrest and apoptosis, cell migration inhibition was observed in cells treated with compound 1 b. Subsequent western blot analysis revealed that the balance between matrix metalloproteinase 2 (MMP2) and tissue inhibitors of metalloproteinase 1 (TIMP1) determines the degree of metalloproteinase activity in MCF-7 cells, thereby regulating cell migration. The improved inhibitory activity imparted by altering the hydrophobic substitution pattern at the bulky cap group is a valuable approach in the development of novel HDAC inhibitors.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Descubrimiento de Drogas , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores de Histona Desacetilasas/síntesis química , Inhibidores de Histona Desacetilasas/química , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/metabolismo , Células K562 , Células MCF-7 , Estructura Molecular , Péptidos Cíclicos/síntesis química , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Relación Estructura-Actividad
7.
Eur J Med Chem ; 52: 111-22, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22465091

RESUMEN

Histone deacetylases inhibitors (HDACIs) have become an attractive class of anticancer agents. In order to find some novel potent HDACIs, we designed and synthesized a series of l-2-benzyloxycarbonylamino-8-(2-pyridyl)-disulfidyloctanoic acid derivatives. All compounds exhibited potent HDAC-inhibitory activity, and two of them had similar potency to TSA. The introduction of 2-amino-4-phenylthiazole or 9-methyleneoxy-fluorenyl group at the surface recognize domain of these HDACIs could greatly increase their HDAC-inhibitory activity. Molecular modeling studies indicated that coordination of the zinc ion by these inhibitors, and formation of hydrogen bond and hydrophobic interaction between inhibitors and HDACs were essential for the HDAC-inhibitory activities of these inhibitors. Asp181, Asp269, Leu276 and Tyr308 in the active site of HDAC2 gave favorable contributions for binding with all compounds.


Asunto(s)
Caprilatos/síntesis química , Caprilatos/farmacología , Técnicas de Química Sintética , Diseño de Fármacos , Histona Desacetilasa 1/antagonistas & inhibidores , Histona Desacetilasa 2/antagonistas & inhibidores , Simulación de Dinámica Molecular , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Caprilatos/química , Línea Celular Tumoral , Histona Desacetilasa 1/química , Histona Desacetilasa 2/química , Inhibidores de Histona Desacetilasas/síntesis química , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Conformación Proteica , Relación Estructura-Actividad , Termodinámica
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA