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1.
Nature ; 586(7828): 248-256, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33028999

RESUMEN

Nitrous oxide (N2O), like carbon dioxide, is a long-lived greenhouse gas that accumulates in the atmosphere. Over the past 150 years, increasing atmospheric N2O concentrations have contributed to stratospheric ozone depletion1 and climate change2, with the current rate of increase estimated at 2 per cent per decade. Existing national inventories do not provide a full picture of N2O emissions, owing to their omission of natural sources and limitations in methodology for attributing anthropogenic sources. Here we present a global N2O inventory that incorporates both natural and anthropogenic sources and accounts for the interaction between nitrogen additions and the biochemical processes that control N2O emissions. We use bottom-up (inventory, statistical extrapolation of flux measurements, process-based land and ocean modelling) and top-down (atmospheric inversion) approaches to provide a comprehensive quantification of global N2O sources and sinks resulting from 21 natural and human sectors between 1980 and 2016. Global N2O emissions were 17.0 (minimum-maximum estimates: 12.2-23.5) teragrams of nitrogen per year (bottom-up) and 16.9 (15.9-17.7) teragrams of nitrogen per year (top-down) between 2007 and 2016. Global human-induced emissions, which are dominated by nitrogen additions to croplands, increased by 30% over the past four decades to 7.3 (4.2-11.4) teragrams of nitrogen per year. This increase was mainly responsible for the growth in the atmospheric burden. Our findings point to growing N2O emissions in emerging economies-particularly Brazil, China and India. Analysis of process-based model estimates reveals an emerging N2O-climate feedback resulting from interactions between nitrogen additions and climate change. The recent growth in N2O emissions exceeds some of the highest projected emission scenarios3,4, underscoring the urgency to mitigate N2O emissions.


Asunto(s)
Óxido Nitroso/análisis , Óxido Nitroso/metabolismo , Agricultura , Atmósfera/química , Productos Agrícolas/metabolismo , Actividades Humanas , Internacionalidad , Nitrógeno/análisis , Nitrógeno/metabolismo
2.
Transl Res ; 212: 89-103, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31344348

RESUMEN

Prostate cancer (PCa) is one of the most common cancers types among men. Development and progression of PCa is associated with aberrant expression of oncogenic splicing-variants (eg, AR-v7), suggesting that dysregulation of the splicing process might represent a potential actionable target for PCa. Expression levels (mRNA and protein) of SF3B1, one of the main components of the splicing machinery, were analyzed in different cohorts of PCa patients (clinically localized [n = 84], highly aggressive PCa [n = 42], and TCGA dataset [n = 497]). Functional and mechanistic assays were performed in response to pladienolide-B in nontumor and tumor-derived prostate cells. Our results revealed that SF3B1 was overexpressed in PCa tissues and its levels were associated with clinically relevant PCa-aggressive features (eg, metastasis/AR-v7 expression). Moreover, inhibition of SF3B1 activity by pladienolide-B reduced functional parameters of aggressiveness (proliferation/migration/tumorspheres-formation/apoptosis) in PCa cell lines, irrespective of AR-v7 expression, and reduced viability of primary PCa cells. Antitumor actions of pladienolide-B involved: (1) inhibition of PI3K/AKT and JNK signaling pathways, (2) modulation of tumor markers and splicing variants (AR-v7/In1-ghrelin), and (3) regulation of key components of mRNA homeostasis-associated machineries (spliceosome/SURF/EJC). Altogether, our results demonstrated that SF3B1 is overexpressed and associated with malignant features in PCa, and its inhibition reduces PCa aggressiveness, suggesting that SF3B1 could represent a novel prognostic biomarker and a therapeutic target in PCa.


Asunto(s)
Antineoplásicos/farmacología , Biomarcadores de Tumor/sangre , Fosfoproteínas/metabolismo , Neoplasias de la Próstata/metabolismo , Factores de Empalme de ARN/metabolismo , Anciano , Línea Celular Tumoral , Proliferación Celular , Estudios de Cohortes , Sistemas de Liberación de Medicamentos , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Fosfoproteínas/genética , Pronóstico , Neoplasias de la Próstata/tratamiento farmacológico , Factores de Empalme de ARN/genética , Empalmosomas/química
3.
World J Emerg Med ; 5(1): 67-71, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25215151

RESUMEN

BACKGROUND: Acute renal failure (ARF) due to obstructive uropathy is a urological emergency. The standard radiological investigations in the emergency setting include X-ray, ultrasonography and computed tomography. But occasionally the cause of obstruction may be elusive. METHODS: We present a case of obstructive uropathy due to bilateral stones presenting as acute renal failure. The patient underwent successful shock wave lithotripsy (SWL) for dissolution of calculi. RESULTS: The patient was successfully treated, and reported asymptomatic in a follow-up. CONCLUSION: Close collaboration between nephrological, urological, and radiological services is required.

4.
Rev. argent. cir ; 60(6): 195-6, jun. 1991. ilus
Artículo en Español | LILACS | ID: lil-105882

RESUMEN

En 122 pacientes consecutivos asistidos se calculó la escala de trauma y el índice de severidad lesional. Los valores hallados fueron en promedio 7,60 y 43,72 para los fallecidos (9,01%) y de 14,60 y 12,05 para los sobrevivientes, siendo ambas diferencias estadísticamente significativas. La posibilidad de sobrevida fue la esperada de acuerdo con el método TRISS. Se concluye que estos índices son útiles para hacer un pronóstico en los pacientes traumatizados y que los resultados obtenidos están acordes a lo esperado según normas internacionales


Asunto(s)
Índices de Gravedad del Trauma , Heridas no Penetrantes/epidemiología , Heridas Penetrantes/epidemiología , Pronóstico , Control de Calidad , Tasa de Supervivencia , Heridas no Penetrantes/mortalidad , Heridas Penetrantes/mortalidad
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