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1.
Nat Commun ; 15(1): 604, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38242880

RESUMEN

Explosivity in erupting volcanoes is controlled by the degassing dynamics and the viscosity of the ascending magma in the conduit. Magma crystallisation enhances both heterogeneous bubble nucleation and increases in magma bulk viscosity. Nanolite crystallisation has been suggested to enhance such processes too, but in a noticeably higher extent. Yet the precise causes of the resultant strong viscosity increase remain unclear. Here we report experimental results for rapid nanolite crystallisation in natural silicic magma and the extent of the subsequent viscosity increase. Nanolite-free and nanolite-bearing rhyolite magmas were subjected to heat treatments, where magmas crystallised or re-crystallised oxide nanolites depending on their initial state, showing an increase of one order of magnitude as oxide nanolites formed. We thus demonstrate that oxide nanolites crystallisation increases magma bulk viscosity mainly by increasing the viscosity of its melt phase due to the chemical extraction of iron, whereas the physical effect of particle suspension is minor, almost negligible. Importantly, we further observe that this increase is sufficient for driving magma fragmentation depending on magma degassing and ascent dynamics.

2.
San Salvador; s.n; 2017. 40 p. graf.
Tesis en Español | LILACS, BISSAL | ID: biblio-1179103

RESUMEN

La Infección de Vías Urinarias (IVU) es una entidad clínica inducida por la invasión, colonización y multiplicación microbiana en el tracto urinario que sobrepasa la capacidad de los mecanismos de defensa del huésped, y es expresión de alteraciones morfológicas o funcionales. La detección y tratamiento precoz de IVU así como el estudio adecuado del paciente son elementos importantes en la prevención de daño renal y progresión a enfermedad renal crónica. Los factores determinantes para producir daño renal son: edad menor de 2 años, infección urinaria febril tratada tardíamente o inadecuadamente, uropatía obstructiva anatómica o funcional, reflujo vesicoureteral con dilatación, y presencia de Echerichia coli. El objetivo del presente estudio fue identificar la sensibilidad de la fosfomicina en los gérmenes causantes de infección de vías urinarias en niños de 3 meses a 12 años en el Hospital Nacional de Niños Benjamín Bloom en el período de junio a septiembre de 2015


Asunto(s)
Infecciones Urinarias , Pediatría , Sistema Urinario , Enterobacteriaceae , Fosfomicina
3.
J Pathol ; 232(1): 32-42, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24155122

RESUMEN

Clear cell tubulopapillary renal cell carcinoma (CCPRCC) is a recently described rare renal malignancy that displays characteristic gross, microscopic and immunohistochemical differences from other renal tumour types. However, CCPRCC remains a very poorly understood entity. We therefore sought to elucidate some of the molecular mechanisms involved in this neoplasm by carrying out targeted next-generation sequencing (NGS) to identify associated mutations, and in addition examined the expression of non-coding (nc) RNAs. We identified multiple somatic mutations in CCPRCC cases, including a recurrent [3/14 cases (21%)] non-synonymous T992I mutation in the MET proto-oncogene, a gene associated with epithelial-to-mesenchymal transition (EMT). Using a microarray approach, we found that the expression of mature (n = 1105) and pre-miRNAs (n = 1105), as well as snoRNA and scaRNAs (n = 2214), in CCPRCC cases differed from that of clear cell renal cell carcinoma (CCRCC) or papillary renal cell carcinoma (PRCC) tumours. Surprisingly, and unlike other renal tumour subtypes, we found that all five members of the miR-200 family were over-expressed in CCPRCC cases. As these miRNAs are intimately involved with EMT, we stained CCPRCC cases for E-cadherin, vimentin and ß-catenin and found that the tumour cells of all cases were positive for all three markers, a combination rarely reported in other renal tumours that could have diagnostic implications. Taken together with the mutational analysis, these data suggest that EMT in CCPRCC tumour cells is incomplete or blocked, consistent with the indolent clinical course typical of this malignancy. In summary, as well as describing a novel pathological mechanism in renal carcinomas, this study adds to the mounting evidence that CCPRCC should be formally considered a distinct entity. Microarray data have been deposited in the GEO database [GEO accession number (GSE51554)].


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Células Renales/genética , Neoplasias Renales/genética , ARN no Traducido/genética , Carcinoma de Células Renales/patología , Análisis por Conglomerados , República Checa , Análisis Mutacional de ADN , ADN de Neoplasias/química , ADN de Neoplasias/genética , Supervivencia sin Enfermedad , Transición Epitelial-Mesenquimal , Estudios de Seguimiento , Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Renales/patología , MicroARNs/química , MicroARNs/genética , MicroARNs/aislamiento & purificación , Análisis de Secuencia por Matrices de Oligonucleótidos , Proto-Oncogenes Mas , ARN Neoplásico/genética , ARN Neoplásico/aislamiento & purificación , ARN no Traducido/química , Estudios Retrospectivos , Análisis de Secuencia de ADN
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