63 research outputs found

    Planktic foraminiferal diversity: logistic growth overprinted by a varying environment

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    This study statistically assesses the relationship between the planktic foraminiferal long-term diversity pattern (~170 Ma to Recent) and four major paleobiological diversification models: (i) the ‘Red Queen’ (Van Valen, 1973; Raup et al., 1973), (ii) the turnover-pulse (Vrba, 1985; Brett and Baird, 1995), (iii) the diversity-equilibrium (Sepkoski, 1978; Rosenzweig, 1995), and (iv) the ‘complicated logistic growth’ (Alroy, 2010a). Our results suggest that the long-term standing diversity pattern and the interplay between origination and extinction rates displayed by this group do not correspond to the first three models, but can be more readily explained by the fourth scenario. Consequently, these patterns are likely controlled by a combination of planktic foraminiferal interspecific competition as well as various environmental changes such as marine global temperatures that could impacted the niches within the upper mixed layer within the oceans. Moreover, as other global long-term patterns have been interpreted as reflecting ‘complicated logistic growth’, this study further suggests that the interplay between abiotic and biotic factors are fundamental elements influencing the evolutionary processes over the extensive history of the biota.Este estudio evalúa estadísticamente la relación entre el patrón de diversidad global de los foraminíferos planctónicos en el largo plazo (~170 Ma al Reciente) y los cuatro modelos de diversificación propuestos desde la rama de la paleobiología: (i) “Reina Roja” (Van Valen, 1973; Raup et al., 1973), (ii) remplazo pausado (Vrba, 1985; Brett y Baird, 1995), (iii) diversidad en equilibrio (Sepkoski, 1978; Rosenzweig, 1995), y (iv) el “crecimiento logístico complicado” (Alroy, 2010a). Nuestros resultados sugieren que la forma de este patrón global de diversidad y la inter-relación entre las tasas de extinción y originación de este grupo no corresponden con los primeros tres modelos anteriormente citados. Sin embargo, estos pueden ser explicados bajo el cuarto escenario. Consecuentemente, las dinámicas de diversidad (i.e. patrón de diversidad y tasas de extinción y originación) de este grupo posiblemente son controladas por la combinación de la competencia interespecífica de los foraminíferos planctónicos y varios cambios ambientales tales como temperaturas globales marinas que pudieron impactar el número de nichos dentro de la capa superior de los océanos.  Además, otros patrones globales de diversidad en el largo plazo han sido interpretados como el reflejo del modelo de crecimiento logístico complicado, lo que sugiere que la relación entre factores abióticos y bióticos tiene un carácter fundamental en los procesos evolutivos que han sucedido a lo largo de la historia de la vida

    Rede de coautoria sobre fósseis colombianos

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    Analyze the published literature on fossils found in Colombia to measure the degree of collaboration and co-authorship networks. We found 1412 documents published by 1411 authors, of which 68% were published as articles, they also found that 60% of this literature has been disseminated in English. It was found that 47% (668 documents) were published collaboratively, while 53% (744 documents) were published individually. The collaboration began in the 1980s. A complete co-authorship network was found by three components that are represented by Bermúdez, Hermann Darío; Honjo, S.; and Doubinger, Jeanne. The authors who have the highest centrality value or the highest recognition as a child can also be identified: Jaramillo Muñoz, Carlos Alberto; Cadena Rueda, Edwin Alberto; Guerrero Díaz, Javier; and Villarroel, Carlos.Analiza la literatura publicada sobre los fósiles encontrados en Colombia para medir el grado de colaboración y las redes de coautoría. Se encontraron 1412 documentos publicados por 1411 autores, de los cuales 68% fueron publicados como artículos, también se encontró que 60% de esta literatura se ha difundido en inglés. Se halló que 47% (668 documentos) se publicaron en colaboración, mientras que 53% (744 documentos) se publicaron individualmente. La colaboración comenzó a partir de la década de los 80. Se encontró una red de coautoría formada por tres componentes que están representados por Bermúdez, Hermann Darío; Honjo, S.; y Doubinger, Jeanne. También se identificaron a los autores que tienen el mayor valor de centralidad o mayor reconocimiento como son: Jaramillo Muñoz, Carlos Alberto; Cadena Rueda, Edwin Alberto; Guerrero Díaz, Javier; y Villarroel, Carlos.Analise a literatura publicada sobre fósseis encontrada na Colômbia para medir o grau de colaboração e redes de coautoria. Encontramos 1412 documentos publicados por 1411 autores, dos quais 68% foram publicados como artigos, eles também descobriram que 60% dessa literatura foi divulgada em inglês. Verificou-se que 47% (668 documentos) foram publicados colaborativamente, enquanto 53% (744 documentos) foram publicados individualmente. A colaboração começou nos anos 80. Uma rede completa de coautoria foi encontrada por três componentes representados por Bermúdez, Hermann Darío; Honjo, S.; e Doubinger, Jeanne. Os autores que têm o maior valor de centralidade ou o maior reconhecimento quando criança também podem ser identificados: Jaramillo Muñoz, Carlos Alberto; Cadena Rueda, Edwin Alberto; Guerrero Díaz, Javier; e Villarroel, Carlos

    A comparative study of the antiangiogenic activity of hydroxytyrosyl alkyl ethers

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    Versión preprint del manuscrito de los autores, publicado finalmente en: Food Chemistry 333 (2020) 127476 con DOI: 10.1016/j.foodchem.2020.127476The phenolic compound hydroxytyrosol and its derivatives are responsible for some of the health benefits of the intake of virgin olive oil, having shown antiangiogenic properties. In this study, we explored the antiangiogenic potential of six synthetic hydroxytyrosyl alkyl ethers (HT C1, C2, C4, C6, C8 and C12). Our results showed that all compounds affected endothelial cell viability in vitro at low micromolar doses. In addition, compounds HT C1, C2, C4 and C6 inhibited endothelial cell migration and formation of tubular-like structures. In these assays, hydroxytyrosyl hexyl ether (HT C6) exhibited the most potent inhibitory activity in vitro, activating as well apoptosis in endothelial cells. Furthermore, the antiangiogenic activity of HT C6 was confirmed in vivo in the chick chorioallantoic membrane assay. Hence, we present hydroxytyrosol synthetic derivative HT C6 as a new antiangiogenic compound and as a good candidate for an antiangiogenic drug in the treatment of angiogenesisdependent diseases.This work was supported by the Spanish Ministry of Science, Innovation and Universities (grants AGL2007-66373 and PID2019- 105010RB-I00), Andalusian Government and FEDER (P12-CTS-1507, UMA18-FEDERJA-220 and funds from group BIO 267), as well as funds from the University of Málaga (“Plan Propio de Investigación y Transferencia”). The “CIBER de Enfermedades Raras” and “CIBER de Enfermedades Cardiovasculares” are initiatives from the ISCIII (Spain). The funders had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript

    Towards sustainable partnerships in global health: the case of the CRONICAS Centre of Excellence in Chronic Diseases in Peru.

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    Human capital requires opportunities to develop and capacity to overcome challenges, together with an enabling environment that fosters critical and disruptive innovation. Exploring such features is necessary to establish the foundation of solid long-term partnerships. In this paper we describe the experience of the CRONICAS Centre of Excellence in Chronic Diseases, based at Universidad Peruana Cayetano Heredia in Lima, Peru, as a case study for fostering meaningful and sustainable partnerships for international collaborative research. The CRONICAS Centre of Excellence in Chronic Diseases was established in 2009 with the following Mission: "We support the development of young researchers and collaboration with national and international institutions. Our motivation is to improve population's health through high quality research." The Centre's identity is embedded in its core values - generosity, innovation, integrity, and quality- and its trajectory is a result of various interactions between multiple individuals, collaborators, teams, and institutions, which together with the challenges confronted, enables us to make an objective assessment of the partnership we would like to pursue, nurture and support. We do not intend to provide a single example of a successful partnership, but in contrast, to highlight what can be translated into opportunities to be faced by research groups based in low- and middle-income countries, and how these encounters can provide a strong platform for fruitful and sustainable partnerships. In defiant contexts, partnerships require to be nurtured and sustained. Acknowledging that all partnerships are not and should not be the same, we also need to learn from the evolution of such relationships, its key successes, hurdles and failures to contribute to the promotion of a culture of global solidarity where mutual goals, mutual gains, as well as mutual responsibilities are the norm. In so doing, we will all contribute to instil a new culture where expectations, roles and interactions among individuals and their teams are horizontal, the true nature of partnerships

    Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

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    Background Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8–13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05–6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50–75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life. Funding Pfizer, Amgen, Merck Sharp & Dohme, Sanofi–Aventis, Daiichi Sankyo, and Regeneron

    Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

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    Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

    Pharmaceutical pollution of the world's rivers

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    Environmental exposure to active pharmaceutical ingredients (APIs) can have negative effects on the health of ecosystems and humans. While numerous studies have monitored APIs in rivers, these employ different analytical methods, measure different APIs, and have ignored many of the countries of the world. This makes it difficult to quantify the scale of the problem from a global perspective. Furthermore, comparison of the existing data, generated for different studies/regions/continents, is challenging due to the vast differences between the analytical methodologies employed. Here, we present a global-scale study of API pollution in 258 of the world's rivers, representing the environmental influence of 471.4 million people across 137 geographic regions. Samples were obtained from 1,052 locations in 104 countries (representing all continents and 36 countries not previously studied for API contamination) and analyzed for 61 APIs. Highest cumulative API concentrations were observed in sub-Saharan Africa, south Asia, and South America. The most contaminated sites were in low- to middle-income countries and were associated with areas with poor wastewater and waste management infrastructure and pharmaceutical manufacturing. The most frequently detected APIs were carbamazepine, metformin, and caffeine (a compound also arising from lifestyle use), which were detected at over half of the sites monitored. Concentrations of at least one API at 25.7% of the sampling sites were greater than concentrations considered safe for aquatic organisms, or which are of concern in terms of selection for antimicrobial resistance. Therefore, pharmaceutical pollution poses a global threat to environmental and human health, as well as to delivery of the United Nations Sustainable Development Goals

    La renovación de la palabra en el bicentenario de la Argentina : los colores de la mirada lingüística

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    El libro reúne trabajos en los que se exponen resultados de investigaciones presentadas por investigadores de Argentina, Chile, Brasil, España, Italia y Alemania en el XII Congreso de la Sociedad Argentina de Lingüística (SAL), Bicentenario: la renovación de la palabra, realizado en Mendoza, Argentina, entre el 6 y el 9 de abril de 2010. Las temáticas abordadas en los 167 capítulos muestran las grandes líneas de investigación que se desarrollan fundamentalmente en nuestro país, pero también en los otros países mencionados arriba, y señalan además las áreas que recién se inician, con poca tradición en nuestro país y que deberían fomentarse. Los trabajos aquí publicados se enmarcan dentro de las siguientes disciplinas y/o campos de investigación: Fonología, Sintaxis, Semántica y Pragmática, Lingüística Cognitiva, Análisis del Discurso, Psicolingüística, Adquisición de la Lengua, Sociolingüística y Dialectología, Didáctica de la lengua, Lingüística Aplicada, Lingüística Computacional, Historia de la Lengua y la Lingüística, Lenguas Aborígenes, Filosofía del Lenguaje, Lexicología y Terminología
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