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1.
Antioxidants (Basel) ; 10(11)2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-34829701

RESUMEN

Shikonin mitigated tumor cell proliferation by elevating reactive oxygen species (ROS) levels. Herein, we investigated the effects of shikonin on renal cancer cell (RCC) cell proliferation. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay indicated that shikonin dose-dependently reduced the proliferation of Caki-1 and ACHN cells. Shikonin remarkably triggered necrosis and apoptosis in Caki-1 and ACHN cells in proportion to its concentration. Moreover, necrostatin-1 recovered cell viability in the presence of shikonin. Elevated ROS levels and mitochondrial dysfunction were also found in shikonin treatment groups. Pretreatment with N-acetyl cysteine remarkably mitigated shikonin-induced cell death and ROS generation. Western blot analysis revealed that shikonin reduced pro-PARP, pro-caspase-3, and Bcl-2 expression and increased cleavage PARP expression. Enhanced autophagy was also found in the shikonin-treated group as evidenced by acridine orange staining. Moreover, light chain 3B (LC3B)-II accumulation and enhanced p62 expression indicated that autophagy occurred in the shikonin-treated group. LC3B knockdown considerably recovered cell viability in the presence of shikonin. Shikonin treatment elevated p38 activity in a dose-dependent manner. In conclusion, our results revealed that shikonin triggered programmed cell death via the elevation of ROS level and p38 activity in different types of RCC cells. These findings suggested that shikonin may be a potential anti-RCC agent.

2.
Medicina (Kaunas) ; 56(12)2020 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-33321738

RESUMEN

Glioblastoma is one of the leading cancer-related causes of death of the brain region and has an average 5-year survival rate of less than 5%. The aim of this study was to investigate the effectiveness of tectorigenin, a naturally occurring flavonoid compound with anti-inflammatory, anti-oxidant, and anti-tumor properties, as a treatment for glioblastoma. A further goal was to use in vitro models to determine the underlying molecular mechanisms. Exposure to tectorigenin for 24 h dose-dependently reduced the viability of glioblastoma cells. Significant cell cycle arrest at G0/G1 phase occurred in the presence of 200 and 300 µM tectorigenin. Treatment with tectorigenin clearly reduced the levels of phosphorylated retinoblastoma protein (p-RB) and decreased the expression of cyclin-dependent protein 4 (CDK4). Tectorigenin treatment also significantly enhanced the expression of p21, a CDK4 inhibitor. Collectively, our findings indicated that tectorigenin inhibited the proliferation of glioblastoma cells by cell cycle arrest at the G0/G1 phase.


Asunto(s)
Glioblastoma , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Puntos de Control de la Fase G1 del Ciclo Celular , Glioblastoma/tratamiento farmacológico , Humanos , Isoflavonas , Fase de Descanso del Ciclo Celular
3.
J Int Med Res ; 46(9): 3809-3818, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29896996

RESUMEN

Objective Higher-intensity counseling sessions increase the smoking abstinence rate. However, counselors are limited in Taiwan. This study was performed to determine whether the addition of one session with a specialist counselor increases the efficacy of a family physician-led smoking cessation program. Methods Participants opted to either visit a family physician for brief counseling and pharmacotherapy (Po) or visit a specialist counselor for an initial session followed by a family physician for brief counseling sessions with pharmacotherapy (P+). The 7-day point prevalence (PP) rate was evaluated at weeks 12 and 24. Results In total, 356 patients were enrolled. In the intention-to-treat analysis, the PP rate at week 12 was higher in the Po than P+ group, but there was no significant difference at week 24. In the per-protocol analysis, the PP rates at weeks 12 and 24 were not significantly different between the Po and P+ groups. The adjusted odds ratios also revealed no significant differences in either the intention-to-treat analysis or the per-protocol analysis between the two groups. Conclusion The addition of one session with a specialist counselor had no benefit over the provision of counseling through a family physician at either 12 or 24 weeks of follow-up.


Asunto(s)
Consejo/métodos , Medicina Familiar y Comunitaria/métodos , Cese del Hábito de Fumar/métodos , Fumar/terapia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Agentes para el Cese del Hábito de Fumar/uso terapéutico , Taiwán , Resultado del Tratamiento
4.
Infect Genet Evol ; 36: 108-115, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26375730

RESUMEN

Since 2010, a new variant of PEDV belonging to Genogroup 2 has been transmitting in China and further spreading to the Unites States and other Asian countries including Taiwan. In order to characterize in detail the temporal and geographic relationships among PEDV strains, the present study systematically evaluated the evolutionary patterns and phylogenetic resolution in each gene of the whole PEDV genome in order to determine which regions provided the maximal interpretative power. The result was further applied to identify the origin of PEDV that caused the 2014 epidemic in Taiwan. Thirty-four full genome sequences were downloaded from GenBank and divided into three non-mutually exclusive groups, namely, worldwide, Genogroup 2 and China, to cover different ranges of secular and spatial trends. Each dataset was then divided into different alignments by different genes for likelihood mapping and phylogenetic analysis. Our study suggested that both nsp3 and S genes contained the highest phylogenetic signal with substitution rate and phylogenetic topology similar to those obtained from the complete genome. Furthermore, the proportion of nodes with high posterior support (posterior probability >0.8) was similar between nsp3 and S genes. The nsp3 gene sequences from three clinical samples of swine with PEDV infections were aligned with other strains available from GenBank and the results suggested that the virus responsible for the 2014 PEDV outbreak in Taiwan clustered together with Clade I from the US within Genogroup 2. In conclusion, the current study identified the nsp3 gene as an alternative marker for a rapid and unequivocal classification of the circulating PEDV strains which provides complementary information to the S gene in identifying the emergence of epidemic strain resulting from recombination.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Evolución Molecular , Virus de la Diarrea Epidémica Porcina/genética , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/virología , Animales , Teorema de Bayes , Infecciones por Coronavirus/historia , Brotes de Enfermedades , Genes Virales , Genotipo , Salud Global , Historia del Siglo XXI , Filogenia , Virus de la Diarrea Epidémica Porcina/clasificación , Glicoproteína de la Espiga del Coronavirus , Porcinos , Enfermedades de los Porcinos/historia , Taiwán/epidemiología
5.
Health Phys ; 108(1 Suppl 1): S37-41, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25551651

RESUMEN

OBJECTIVES: Compared to clinical x-ray equipment, non-medical x-ray producing equipment has been subject to limited radiation safety oversight. However, the concern of unnecessary or even hazardous personnel exposure has always been associated with the use of ionizing radiation. The goal of this paper is to review the process of developing and implementing a systematic and structured radiation safety program at a large university that aims to provide adequate oversight and education to ensure personnel safety. METHODS: At Duke University, the program currently consists of 26 active and 11 inactive x-ray authorized users and over 50 active x-ray tubes. The main foci of the non-medical x-ray program are equipment inventory, training for authorized user and operator, personnel dosimetry, and future regular inspections. The requirement for personnel dosimetry was investigated by deploying film badges on open beam equipment. Quarterly environmental badge reports were collected and served as one of the justifications for the discontinuation of personnel badges. CONCLUSION: In order to maintain adequate oversight and awareness of radiation safety, our office found success through establishing an open channel of communication, providing regular refresher training and conducting regular inspections.


Asunto(s)
Hospitales Universitarios , Protección Radiológica/métodos , Administración de la Seguridad/métodos , Administración de la Seguridad/organización & administración , Humanos , Protección Radiológica/instrumentación
6.
Adv Mater ; 27(2): 282-7, 2015 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-25420719

RESUMEN

A novel organic/graphene/inorganic -heterostructure, consisting of a graphene layer encapsulated by n- and p-type photoactive materials with complementary absorptions, enables the control of dual n- and p-typed transport behaviors of a graphene transistor under selective UV or visible light illumination. A graphene-based p-n junction created by spatially patterned wavelength-selective illumination using the organic/graphene/inorganic heterostructure is also demonstrated.

7.
ACS Nano ; 6(7): 6215-21, 2012 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-22681443

RESUMEN

This paper presents an innovative approach to fabricating controllable n-type doping graphene transistors with extended air stability by using self-encapsulated doping layers of titanium suboxide (TiOx) thin films, which are an amorphous phase of crystalline TiO(2) and can be solution processed. The nonstoichiometry TiOx thin films consisting of a large number of oxygen vacancies exhibit several unique functions simultaneously in the n-type doping of graphene as an efficient electron-donating agent, an effective dielectric screening medium, and also an encapsulated layer. A novel device structure consisting of both top and bottom coverage of TiOx thin layers on a graphene transistor exhibited strong n-type transport characteristics with its Dirac point shifted up to -80 V and an enhanced electron mobility with doping. Most interestingly, an extended stability of the device without rapid degradation after doping was observed when it was exposed to ambient air for several days, which is not usually observed in other n-type doping methods in graphene. Density functional theory calculations were also employed to explain the observed unique n-type doping characteristics of graphene using TiOx thin films. The technique of using an "active" encapsulated layer with controllable and substantial electron doping on graphene provides a new route to modulate electronic transport behavior of graphene and has considerable potential for the future development of air-stable and large-area graphene-based nanoelectronics.

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