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1.
Food Chem ; 340: 127927, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32889214

RESUMEN

The effects of the support on the catalytic performance of supported Ni catalysts for the hydrogenation of soybean oil were examined. The turnover frequency (TOF) for Ni/TiO2 was greater than those for other Ni catalysts. Among the examined Ni catalysts, the Ni/TiO2 catalysts were effective for the reduction of trans fatty acid (TFA) levels (minimum 10.5%) in hydrogenated oils at an iodine value (IV) of 70, independent of the difference in the crystalline structure of TiO2. In addition, the oils hydrogenated by Ni/TiO2 had suitable properties for feedstock of margarine and vegetable shortening. The highly dispersed Ni nanoparticles formed by reduction of the NiO monolayer on the surface of TiO2 contribute to increasing the catalytic activity and to reducing the TFA levels.


Asunto(s)
Níquel/química , Aceite de Soja/química , Titanio/química , Ácidos Grasos trans/química , Catálisis , Hidrogenación , Margarina , Nanopartículas del Metal
2.
J Toxicol Pathol ; 30(3): 209-216, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28798528

RESUMEN

Some chemicals are known to be lung carcinogens in rodents. While many studies using two-stage models have administered medium or high doses to mice, few have tested lower doses. The dose dependence of urethane, 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and benzo[a]pyrene (B[a]P), three well-known lung carcinogens at high doses, has not been sufficiently reported in lower dose ranges. Our study evaluated the tumorigenicity of urethane, NNK, and B[a]P at 26 weeks after a single intraperitoneal administration of each compound within medium to low dose in male and/or female A/JJmsSlc (A/J) mice. Dose-dependent tumorigenesis was demonstrated histopathologically for the three compounds. These results suggested that the tumorigenicity of these chemicals is dose dependent in A/J mice, even at lower doses than previously reported.

3.
PLoS One ; 9(3): e89885, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24594519

RESUMEN

Most epithelial tissues retain stem/progenitor cells to maintain homeostasis of the adult tissues; however, the existence of a thymic epithelial cell (TEC) progenitor capable of maintaining homeostasis of the postnatal thymus remains unclear. Here, we show that a cell population expressing high levels of Meis1, a homeodomain transcription factor, is enriched in TECs with an immature cellular phenotype. These TECs selectively express genes involved in embryonic thymic organogenesis and epithelial stem cell maintenance, and also have the potential to proliferate and differentiate into mature TEC populations. Furthermore, postnatal inactivation of Meis1 in TECs caused disorganization of the thymic architecture, which ultimately leads to premature disappearance of the thymus. There was an age-associated reduction in the proportion of the TEC population expressing high levels of Meis1, which may also be related to thymic involution. These findings indicate that Meis1 is potentially involved in the maintenance of postnatal TECs with progenitor activity that is required for homeostasis of the postnatal thymus.


Asunto(s)
Células Epiteliales/metabolismo , Proteínas de Homeodominio/metabolismo , Proteínas de Neoplasias/metabolismo , Timo/citología , Envejecimiento/metabolismo , Animales , Animales Recién Nacidos , Atrofia , Diferenciación Celular , Microambiente Celular , Células Epiteliales/citología , Eliminación de Gen , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Ratones Endogámicos C57BL , Proteína 1 del Sitio de Integración Viral Ecotrópica Mieloide , Proteínas de Neoplasias/genética , Especificidad de Órganos
4.
Appl Radiat Isot ; 81: 366-70, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23582493

RESUMEN

Sediment trap observations of lakes in western Japan before and after Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident indicate that changes in the radioactive Cs discharge are influenced by fluctuations in precipitation and geomorphological conditions in each catchment. Contributions of FDNPP-derived (134,137)Cs to the sediment decreased from 19-48% to 10-15% within a few months, implying that the major transport processes of FDNPP-derived (134,137)Cs have changed from direct fallout to transport by soil particles.


Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Fukushima , Sedimentos Geológicos/análisis , Lagos/análisis , Monitoreo de Radiación/métodos , Ceniza Radiactiva/análisis , Contaminantes Radiactivos del Agua/análisis , Sedimentos Geológicos/química , Japón , Lagos/química , Dosis de Radiación
5.
Int J Oncol ; 40(1): 71-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21947321

RESUMEN

CD133 has been recognized as a specific cell surface marker for cancer stem cells in various tumors, although its biological functions and transcriptional regulation remain unclear. We found that the CD133 expression level was up-regulated in the lung cancer cell lines N417, H358, and A549, when these cell lines were cultured under hypoxic conditions. Among the five promoters (P1-P5) of human CD133 gene loci, P1 promoter was most strongly associated with hypoxia-induced promoter activity of CD133 gene expression. The P1 promoter possesses several cis-regulatory elements, including RUNT, GATA, ETS, OCT, SRY, and CREB-binding sites. A series of deletion and base substitution mutants of the P1 promoter revealed that OCT- and SRY-binding sites are important for hypoxia-induced promoter activity. The chromatin immunoprecipitation assay further confirmed the direct binding of Octamer biding trans-cription factor 3/4 (OCT4) and/or SRY-box containing gene 2 (SOX2) to the P1 promoter region of CD133 gene loci. In addition, the enhancement of both OCT4 and SOX2 expression by the α subunit of hypoxia-inducible factors (HIF1α and HIF2α) was required for hypoxia-induced CD133 expression. Knockdown of OCT4 or SOX2 expression in N417 cells with stabilized HIF1α and/or HIF2α abolished CD133P1 activity, while ectopic OCT4 or SOX2 expression triggers CD133P1 activity in the absence of HIF1α or HIF2α. Thus, in the hypoxic conditions, OCT4 and SOX2, both of which are induced by HIF1α/HIF2α. promote CD133 expression in the lung cancer cells via their direct interaction with the P1 promoter.


Asunto(s)
Antígenos CD/biosíntesis , Glicoproteínas/biosíntesis , Neoplasias Pulmonares/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/biosíntesis , Proteínas de Transporte de Catión Orgánico/biosíntesis , Factores de Transcripción SOXB1/biosíntesis , Antígeno AC133 , Antígenos CD/genética , Secuencia de Bases , Sitios de Unión , Hipoxia de la Célula/fisiología , Línea Celular Tumoral , Glicoproteínas/genética , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Pulmonares/genética , Datos de Secuencia Molecular , Factor 3 de Transcripción de Unión a Octámeros/genética , Proteínas de Transporte de Catión Orgánico/genética , Péptidos/genética , Regiones Promotoras Genéticas , Factores de Transcripción SOXB1/genética , Transcripción Genética , Regulación hacia Arriba
6.
Artículo en Inglés | MEDLINE | ID: mdl-21722082

RESUMEN

Measurements of ultrafine particles (UFPs) with diameters smaller than 100 nm were made with a Scanning Mobility Particle Sizer on the roadside of the Tateyama-Kurobe Alpine route on the western slope of Mt. Tateyama, Japan, in the summer and autumn of 2007 and 2008. The number concentrations of nanoparticles (NPs) with diameters smaller than 50 nm increased sharply in the morning. This increase agreed with that of the NO concentration, which is a good indicator of vehicle emissions. Although the peak concentration of NO was also detected in the late afternoon, the concentrations of NPs did not increase. The vehicle emission of UFPs may vary considerably with the driving conditions. The emission of NPs might have been accelerated under a high engine-load condition. The NP concentrations in October were much higher than those in August, although there were more buses in August than in October. The number size distribution in the morning was bimodal, with the first peak around 20-30 nm and the second one around 70-80 nm. The first peak became small during the daytime. The first peak disappeared, and a small second peak remained through midnight.


Asunto(s)
Contaminantes Atmosféricos/análisis , Altitud , Monitoreo del Ambiente , Emisiones de Vehículos/análisis , Japón , Nanopartículas/análisis , Tamaño de la Partícula , Estaciones del Año
7.
Parasitol Res ; 105(1): 281-6, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19352703

RESUMEN

Plasmodium berghei ANKA causes lethal malaria in mice. It is well established that C57BL/6 mice die early with fulminant symptoms including convulsion, whereas BALB/c mice survive this phase and die later of anemia and prostration. Early death in C57BL/6 mice has been considered to result from the adverse effects of inflammatory cytokines. To elucidate the CD4(+) T cell responses in early death due to severe malaria, the kinetics of CD4(+) T cells were compared by analyzing cell surface markers and the production of cytokines and transcription factors. The results revealed that cytokine production by CD4(+) T cells was induced as early as 5 days after infection and the maintenance of higher levels of IL-4 and IL-10 may be associated with the protection of BALB/c mice from early death. These results suggest that parasite control in the early phase of infection may be important for the development of an effective vaccine.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Malaria/inmunología , Plasmodium berghei/inmunología , Animales , Citocinas/metabolismo , Perfilación de la Expresión Génica , Malaria/parasitología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Parasitemia , Análisis de Supervivencia , Subgrupos de Linfocitos T/inmunología , Factores de Transcripción/biosíntesis
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