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1.
Data Brief ; 50: 109482, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37636128

RESUMEN

Here, we present and release the Global Rainfall Erosivity Database (GloREDa), a multi-source platform containing rainfall erosivity values for almost 4000 stations globally. The database was compiled through a global collaboration between a network of researchers, meteorological services and environmental organisations from 65 countries. GloREDa is the first open access database of rainfall erosivity (R-factor) based on hourly and sub-hourly rainfall records at a global scale. This database is now stored and accessible for download in the long-term European Soil Data Centre (ESDAC) repository of the European Commission's Joint Research Centre. This will ensure the further development of the database with insertions of new records, maintenance of the data and provision of a helpdesk. In addition to the annual erosivity data, this release also includes the mean monthly erosivity data for 94% of the GloREDa stations. Based on these mean monthly R-factor values, we predict the global monthly erosivity datasets at 1 km resolution using the ensemble machine learning approach (ML) as implemented in the mlr package for R. The produced monthly raster data (GeoTIFF format) may be useful for soil erosion prediction modelling, sediment distribution analysis, climate change predictions, flood, and natural disaster assessments and can be valuable inputs for Land and Earth Systems modelling.

2.
Data Brief ; 25: 104398, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31516931

RESUMEN

This contribution contains a GPlates digital reconstruction of the northern Andes and southern Caribbean margin for the last 90 Ma. It is built using different strain datasets fully described in "Continental Margin Response to Multiple Arc-Continent Collisions: the Northern Andes-Caribbean Margin" [1]. Two digital reconstructions are included here: one is a rigid block reconstruction, and the other is a continuously closing polygon reconstruction digitized every one -million years. We placed the South and North American plates at the root of the reconstruction tree, so that the Andean blocks move with respect to the former, and the Caribbean Plate, and related intra-oceanic arcs with respect to the latter. These reconstructions can be used as templates to place in palinspastic space any dataset that can be represented by lines or points.

3.
Sci Rep ; 7(1): 4175, 2017 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-28646132

RESUMEN

The exposure of the Earth's surface to the energetic input of rainfall is one of the key factors controlling water erosion. While water erosion is identified as the most serious cause of soil degradation globally, global patterns of rainfall erosivity remain poorly quantified and estimates have large uncertainties. This hampers the implementation of effective soil degradation mitigation and restoration strategies. Quantifying rainfall erosivity is challenging as it requires high temporal resolution(<30 min) and high fidelity rainfall recordings. We present the results of an extensive global data collection effort whereby we estimated rainfall erosivity for 3,625 stations covering 63 countries. This first ever Global Rainfall Erosivity Database was used to develop a global erosivity map at 30 arc-seconds(~1 km) based on a Gaussian Process Regression(GPR). Globally, the mean rainfall erosivity was estimated to be 2,190 MJ mm ha-1 h-1 yr-1, with the highest values in South America and the Caribbean countries, Central east Africa and South east Asia. The lowest values are mainly found in Canada, the Russian Federation, Northern Europe, Northern Africa and the Middle East. The tropical climate zone has the highest mean rainfall erosivity followed by the temperate whereas the lowest mean was estimated in the cold climate zone.

4.
Arch. med ; 15(2): 305-319, July-Dec.2015.
Artículo en Español | LILACS | ID: lil-785585

RESUMEN

Desarrollar una metodología diagnóstica de la dinámica cardíaca neonatalfundamentada en la geometría fractal, la teoría de los sistemas dinámicos yla ocupación espacial del atractor cardíaco en el espacio fractal de Box-Counting.Materiales y métodos: inicialmente se realizó una inducción matemática condos registros Holter evaluados clínicamente como normales y tres con patologíaaguda provenientes de la Unidad de Cuidados Intensivos (UCI). Se generó la secuencia de valores de la frecuencia cardíaca (FC) tomando para ello los valoresmáximos y mínimos de la FC/hora y total de latidos/hora durante 21 horas. Seconstruyeron atractores cardíacos, para calcular la dimensión fractal y los espaciosde ocupación en el espacio fractal de Box-Counting, estableciendo diferenciasentre normalidad y enfermedad. Los resultados de la inducción fueron aplicadosa 5 dinámicas normales y 25 patológicas, para confirmar los resultados obtenidosmediante un estudio ciego. Resultados: la ocupación espacial de los atractorescaóticos evaluados en la inducción matemática, evidenció que valores iguales osuperiores a 98 en la rejilla Kg son característicos de normalidad, y los menoresa 98 corresponden a enfermedad aguda; valores que fueron confirmados con loscasos restantes, logrando valores de sensibilidad y especificidad de 100%, y uncoeficiente kappa de 1. Conclusiones: se desarrolló un nuevo diagnóstico físicoy matemático de aplicación clínica para evaluar la dinámica cardíaca neonatal,que permite detectar tempranamente alteraciones de potencial gravedad y señalarcuantitativamente el nivel de agudización de alteraciones específicas, de utilidadpara la toma de decisiones clínicas en la UCI...


Asunto(s)
Humanos , Fractales , Frecuencia Cardíaca , Recién Nacido , Dinámicas no Lineales
5.
Nat Neurosci ; 18(12): 1819-31, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26523646

RESUMEN

Brain transcriptome and connectome maps are being generated, but an equivalent effort on the proteome is currently lacking. We performed high-resolution mass spectrometry-based proteomics for in-depth analysis of the mouse brain and its major brain regions and cell types. Comparisons of the 12,934 identified proteins in oligodendrocytes, astrocytes, microglia and cortical neurons with deep sequencing data of the transcriptome indicated deep coverage of the proteome. Cell type-specific proteins defined as tenfold more abundant than average expression represented about a tenth of the proteome, with an overrepresentation of cell surface proteins. To demonstrate the utility of our resource, we focused on this class of proteins and identified Lsamp, an adhesion molecule of the IgLON family, as a negative regulator of myelination. Our findings provide a framework for a system-level understanding of cell-type diversity in the CNS and serves as a rich resource for analyses of brain development and function.


Asunto(s)
Encéfalo/citología , Encéfalo/fisiología , Neuronas/fisiología , Proteoma/genética , Animales , Células HEK293 , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
6.
Arch. med ; 15(1): 33-45, jun. 2015.
Artículo en Español | LILACS | ID: lil-776036

RESUMEN

Objetivo: confirmar la capacidad diagnóstica de una metodología basada en la teoría de probabilidad en casos de arritmia. Materiales y métodos: se realiza un estudio ciego, en el que se analizaron 10 Holter normales y 90 con diferentes tipos de arritmia, de pacientes mayores de 21 años. Se enmascara el diagnóstico convencional y se calcula la probabilidad de rangos de frecuencias cardiacas máximas, mínimas e intermedias cada hora, y de número de latidos por hora, para determinar el diagnóstico matemático de acuerdo con los tres parámetros establecidos previamente. Finalmente, se desenmascara el diagnóstico convencional, que fue tomado como Estándar de Oro, y se realiza un análisis de la concordancia diagnóstica para diferenciar normalidad y arritmia aguda. Resultados: los Holternormales, presentan valores matemáticos característicos de normalidad o en evolucióna enfermedad, mientras que todos los casos patológicos son diagnosticados por la metodología como en evolución a enfermedad o enfermos. Se obtiene una sensibilidad del 100%, una especificidad del 70%, un VPP de 93,33% y un VPNde 100%, y el coeficiente Kappa presenta un valor de 0,82. Conclusiones: la aplicación de la metodología en el estudio de alteraciones arrítmicas, evidencia un orden matemático mediante el cual se logra diferenciar normalidad de enfermedad y detectar estados de evolución a la enfermedad aun en estados clínicos con diagnóstico normal, de posible utilidad preventiva a nivel clínico.


Asunto(s)
Arritmias Cardíacas , Diagnóstico , Electrocardiografía Ambulatoria , Teoría de la Probabilidad
7.
Crit Care Med ; 42(4): 771-80, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24365860

RESUMEN

OBJECTIVES: To perform a complete immunological characterization of compensatory anti-inflammatory response syndrome in patients with sepsis and to explore the relationship between these changes and clinical outcomes of 28-day mortality and secondary infections. DESIGN: Prospective single-center study conducted between April 2011 and December 2012. SETTING: ICUs from Hospital Universitario San Vicente Fundación at Medellin, Colombia. PATIENTS: One hundred forty-eight patients with severe sepsis. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: At days 0, 1, 3, 5, 10, and 28, we determined the expression of HLA-DR in monocytes and the apoptosis and the proliferation index in T lymphocytes, as well as the levels of tumor necrosis factor-α, interleukin-6, interleukin-1ß, interleukin-10, and transforming growth factor-ß in both plasma and cell culture supernatants of peripheral blood mononuclear cells. The mean percentage of HLA-DR was 60.7 at enrollment and increased by 0.9% (95% CI, 0.7-1.2%) per day. The mean percentage of CD4 T cells and CD8 T cells AV+/7-AAD- at enrollment was 37.2% and 20.4%, respectively, but it diminished at a rate of -0.5% (95% CI, -0.7% to -0.3%) and -0.3% (95% CI, -0.4% to -0.2%) per day, respectively. Plasma levels of interleukin-6 and interleukin-10 were 290 and 166 pg/mL and decreased at a rate of -7.8 pg/mL (95% CI, -9.5 to -6.1 pg/mL) and -4 pg/mL (95% CI, -5.1 to -2.8 pg/mL) per day, respectively. After controlling for confounders, only sustained plasma levels of interleukin-6 increase the risk of death (hazard ratio 1.003; 95% CI, 1.001-1.006). CONCLUSIONS: We found no evidence to support a two-phase model of sepsis pathophysiology. However, immunological variables did behave in a mixed and time-dependent manner. Further studies should evaluate changes over time of interleukin-6 plasma levels as a prognostic biomarker for critically ill patients.


Asunto(s)
Antígenos HLA-DR/biosíntesis , Mediadores de Inflamación/inmunología , Leucocitos Mononucleares/inmunología , Sepsis/inmunología , APACHE , Anciano , Apoptosis , Proliferación Celular , Comorbilidad , Femenino , Humanos , Mediadores de Inflamación/sangre , Unidades de Cuidados Intensivos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Puntuaciones en la Disfunción de Órganos , Estudios Prospectivos , Grupos Raciales , Sepsis/sangre
8.
BMC Infect Dis ; 13: 345, 2013 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-23883312

RESUMEN

BACKGROUND: Sepsis has several clinical stages, and mortality rates are different for each stage. Our goal was to establish the evolution and the determinants of the progression of clinical stages, from infection to septic shock, over the first week, as well as their relationship to 7-day and 28-day mortality. METHODS: This is a secondary analysis of a multicenter cohort of inpatients hospitalized in general wards or intensive care units (ICUs). The general estimating equations (GEE) model was used to estimate the risk of progression and the determinants of stages of infection over the first week. Cox regression with time-dependent covariates and fixed covariates was used to determine the factors related with 7-day and 28-day mortality, respectively. RESULTS: In 2681 patients we show that progression to severe sepsis and septic shock increases with intraabdominal and respiratory sources of infection [OR = 1,32; 95%IC = 1,20-1,46 and OR = 1.21, 95%CI = 1,11-1,33 respectively], as well as according to Acute Physiology and Chronic Health Evaluation II (APACHE II) [OR = 1,03; 95%CI = 1,02-1,03] and Sequential Organ Failure Assessment (SOFA) [OR = 1,16; 95%CI = 1,14-1,17] scores. The variables related with first-week mortality were progression to severe sepsis [HR = 2,13; 95%CI = 1,13-4,03] and septic shock [HR = 3,00; 95%CI = 1,50-5.98], respiratory source of infection [HR = 1,76; 95%IC = 1,12-2,77], APACHE II [HR = 1,07; 95% CI = 1,04-1,10] and SOFA [HR = 1,09; 95%IC = 1,04-1,15] scores. CONCLUSIONS: Intraabdominal and respiratory sources of infection, independently of SOFA and APACHE II scores, increase the risk of clinical progression to more severe stages of sepsis; and these factors, together with progression of the infection itself, are the main determinants of 7-day and 28-day mortality.


Asunto(s)
Sepsis/epidemiología , Sepsis/mortalidad , APACHE , Adulto , Anciano , Análisis de Varianza , Estudios de Cohortes , Colombia/epidemiología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Sepsis/diagnóstico , Sepsis/patología
9.
Ann Neurol ; 71(2): 227-44, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22367995

RESUMEN

OBJECTIVE: To investigate the impact of single or repeated episodes of reversible demyelination on long-term locomotor performance and neuroaxonal integrity, and to analyze the myelin proteome after remyelination and during aging. METHODS: Long-term locomotor performance of previously cuprizone-treated animals was monitored using the motor skill sequence (MOSS). Quantitative analysis of myelin proteome and histopathological analysis of neuronal/axonal integrity was performed after successful remyelination. Histopathological findings observed in experimental chronic remyelinated lesions were verified in chronic remyelinated lesions from multiple sclerosis (MS) patients. RESULTS: Following cessation of cuprizone treatment, animals showed an initial recovery of locomotor performance. However, long after remyelination was completed (approximately 6 months after the last demyelinating episode), locomotor performance again declined in remyelinated animals as compared to age-matched controls. This functional decline was accompanied by brain atrophy and callosal axonal loss. Furthermore, the number of acutely damaged amyloid precursor protein-positive (APP+) axons was still significantly elevated in long-term remyelinated animals as compared to age-matched controls. Confocal analysis revealed that a substantial proportion of these APP+ spheroids were ensheathed by myelin, a finding that was confirmed in the chronic remyelinated lesions of MS patients. Moreover, quantitative analysis of myelin proteome revealed that remyelinated myelin displays alterations in composition that are in some aspects similar to the myelin of older animals. INTERPRETATION: We propose that even after completed remyelination, axonal degeneration continues to progress at a low level, accumulating over time, and that once a threshold is passed axonal degeneration can become functionally apparent in the long-term. The presented model thus mimics some of the aspects of axonal degeneration in chronic progressive MS.


Asunto(s)
Enfermedades Desmielinizantes/fisiopatología , Destreza Motora/fisiología , Esclerosis Múltiple Crónica Progresiva/fisiopatología , Vaina de Mielina/fisiología , Envejecimiento , Animales , Axones/patología , Axones/ultraestructura , Cuprizona/administración & dosificación , Cuprizona/toxicidad , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/patología , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Endogámicos C57BL , Inhibidores de la Monoaminooxidasa/administración & dosificación , Inhibidores de la Monoaminooxidasa/toxicidad , Destreza Motora/efectos de los fármacos , Vaina de Mielina/patología , Factores de Tiempo
10.
PLoS One ; 6(7): e22735, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21818378

RESUMEN

Glial dysfunction has been implicated in a number of neurodegenerative diseases. In this study we investigated the consequences of glial and oligodendrocyte ablation on neuronal integrity and survival in Drosophila and adult mice, respectively. Targeted genetic ablation of glia was achieved in the adult Drosophila nervous system using the GAL80-GAL4 system. In mice, oligodendrocytes were depleted by the injection of diphtheria toxin in MOGi-Cre/iDTR double transgenic animals. Acute depletion of oligodendrocytes induced axonal injury, but did not cause neuronal cell death in mice. Ablation of glia in adult flies triggered neuronal apoptosis and resulted in a marked reduction in motor performance and lifespan. Our study shows that the targeted depletion of glia triggers secondary neurotoxicity and underscores the central contribution of glia to neuronal homeostasis. The models used in this study provide valuable systems for the investigation of therapeutic strategies to prevent axonal or neuronal damage.


Asunto(s)
Axones/patología , Oligodendroglía/patología , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Astrocitos/patología , Axones/efectos de los fármacos , Toxina Diftérica/farmacología , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/metabolismo , Integrasas/metabolismo , Locomoción/efectos de los fármacos , Longevidad/efectos de los fármacos , Ratones , Microglía/efectos de los fármacos , Microglía/metabolismo , Microglía/patología , Oligodendroglía/efectos de los fármacos
11.
J Cell Biol ; 189(2): 223-32, 2010 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-20404108

RESUMEN

Oligodendrocytes secrete vesicles into the extracellular space, where they might play a role in neuron-glia communication. These exosomes are small vesicles with a diameter of 50-100 nm that are formed within multivesicular bodies and are released after fusion with the plasma membrane. The intracellular pathways that generate exosomes are poorly defined. Because Rab family guanosine triphosphatases (GTPases) together with their regulators are important membrane trafficking organizers, we investigated which Rab GTPase-activating proteins interfere with exosome release. We find that TBC1D10A-C regulate exosome secretion in a catalytic activity-dependent manner. We show that Rab35 is the target of TBC1D10A-C and that the inhibition of Rab35 function leads to intracellular accumulation of endosomal vesicles and impairs exosome secretion. Rab35 localizes to the surface of oligodendroglia in a GTP-dependent manner, where it increases the density of vesicles, suggesting a function in docking or tethering. These findings provide a basis for understanding the biogenesis and function of exosomes in the central nervous system.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Exosomas/metabolismo , Proteínas Activadoras de GTPasa/metabolismo , Oligodendroglía/fisiología , Proteínas de Unión al GTP rab/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Calcio/metabolismo , Línea Celular , Membrana Celular/metabolismo , Exocitosis/fisiología , Proteínas Activadoras de GTPasa/genética , Humanos , Ratones , Oligodendroglía/citología , Técnicas de Placa-Clamp , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas de Unión al GTP rab/genética
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