108 research outputs found

    Socioeconomic and environmental determinants of adolescent asthma in urban Latin America: an ecological analysis

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    The prevalence of asthma is high in urban areas of many Latin-American countries where societies show high levels of inequality and different levels of development. This study aimed to examine the relationship between asthma symptoms prevalence in adolescents living in Latin American urban centers and socioeconomic and environmental determinants measured at the ecological level. Asthma prevalence symptoms were obtained from the International Study of Asthma and Allergies in Childhood (ISAAC) phase III. A hierarchical conceptual framework was defined and the explanatory variables were organized in three levels: distal, intermediate, proximal. Linear regression models weighed by sample size were undertaken between asthma prevalence and the selected variables. Asthma prevalence was positively associated with Gini index, water supply and homicide rate, and inversely associated with the Human Development Index, crowding and adequate sanitation. This study provides evidence of the potential influence of poverty and social inequalities on current wheezing in adolescents in a complex social context like Latin America.A prevalência da asma é alta nas áreas urbanas da América Latina, onde as sociedades exibem altos níveis de desigualdade e diferente grau de desenvolvimento. O objetivo é examinar a relação entre a prevalência de sintomas asmáticos em adolescentes de centros urbanos da América Latina e determinantes socioeconômicos e ambientais medidos no nível ecológico. A prevalência de sintomas asmáticos foi obtida do International Study of Asthma and Allergies in Childhood (ISAAC), fase III. Foi definido um modelo conceitual hierárquico. As variáveis explicativas foram organizadas em três níveis: distal, intermediário, proximal. Ajustaram-se modelos de regressão lineal ponderados pelo tamanho amostral entre prevalência de sintomas asmáticos e variáveis selecionadas. A prevalência da asma foi associada positivamente com índice de Gini, índice de desenvolvimento humano, subministro de água potável, e inversamente com aglomeração e saneamento. Em conclusão, este estudo ecológico fornece evidência da influência da pobreza e da desigualdade social sobre os sintomas asmáticos em adolescentes em um contexto social complexo como o da América Latina

    Metabolic profiles of six African cultivars of cassava (Manihot esculenta Crantz) highlight bottlenecks of root yield

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    Open Access Article; Published online: 17 Jan 2020Cassava is an important staple crop in sub‐Saharan Africa, due to its high productivity even on nutrient poor soils. The metabolic characteristics underlying this high productivity are poorly understood including the mode of photosynthesis, reasons for the high rate of photosynthesis, the extent of source/sink limitation, the impact of environment, and the extent of variation between cultivars. Six commercial African cassava cultivars were grown in a greenhouse in Erlangen, Germany, and in the field in Ibadan, Nigeria. Source leaves, sink leaves, stems and storage roots were harvested during storage root bulking and analyzed for sugars, organic acids, amino acids, phosphorylated intermediates, minerals, starch, protein, activities of enzymes in central metabolism and yield traits. High ratios of RuBisCO:phosphoenolpyruvate carboxylase activity support a C3 mode of photosynthesis. The high rate of photosynthesis is likely to be attributed to high activities of enzymes in the Calvin–Benson cycle and pathways for sucrose and starch synthesis. Nevertheless, source limitation is indicated because root yield traits correlated with metabolic traits in leaves rather than in the stem or storage roots. This situation was especially so in greenhouse‐grown plants, where irradiance will have been low. In the field, plants produced more storage roots. This was associated with higher AGPase activity and lower sucrose in the roots, indicating that feedforward loops enhanced sink capacity in the high light and low nitrogen environment in the field. Overall, these results indicated that carbon assimilation rate, the K battery, root starch synthesis, trehalose, and chlorogenic acid accumulation are potential target traits for genetic improvement

    El edificio de la biblioteca: planificación, diseño y ambientación de sus espacios para nuevos servicios y funciones

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    En la actualidad la incorporación de nuevas funciones, servicios, productos y espacios en las bibliotecas, requieren ser apoyados por cambios en la estructura fí­sica del edificio que refuerce el papel de esta institución como lugar de reunión, encuentro y socialización. Esta comunicación es un primer acercamiento a los necesarios cambios que en sus espacios interiores y exteriores ha de encarar la biblioteca para erigirse como ese lugar ideal a donde la comunidad va a satisfacer sus necesidades y requerimientos, de ocio, formación e información. El estudio parte de un análisis de buenas prácticas que en este sentido se desarrollan en múltiples bibliotecas a nivel global, concluyendo con una relación de tendencias que en cuanto a la planificación, diseño y ambientación en el edificio para bibliotecas hoy son una constante a considerar como experiencias a considerar

    Situational diagnostic of the breeding of guinea pigs in Cajamarca

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    Se realizó una encuesta en julio de 2004 a 160 familias criadoras de cuyes en el distrito de Santa Cruz, Cajamarca, con el objetivo de caracterizar los sistemas de producción de cuyes. El 44.6% de los productores tenía más de 50 años de edad y el 42% de las esposas tenía entre 31 a 50 años. Primaria era el grado de instrucción predominante. La ocupación del jefe de familia era la agricultura (95.4%) y de la esposa era su casa (97.2%). La crianza de cuyes era conducida por el ama de casa bajo un sistema familiar o tradicional. Se encontró un promedio de 20.4 cuyes por familia, criados en un solo grupo sin distinción de clase, sexo y edad, de preferencia en la cocina (88.8%), donde permanecían sueltos (73.8%) o en pozas (21.9%). La alimentación se basó en forrajes, malezas y residuos de cocina. Las principales enfermedades reportadas fueron ectoparásitos (90.1%) y la “peste” (76%). El 71.2% de las familias destinaba los cuyes para autoconsumo y venta, y el 28.2% sólo para autoconsumo. El 96.2% de los encuestados no disponía de servicios de asistencia técnica, créditos, insumos, etc. El 67.5% de los criadores consideraba que mejorarían su crianza con asistencia técnica.A survey was conducted in July 2004 to 160 families rearing Guinea pigs in the district of Santa Cruz, Cajamarca, with the aim of characterizing the production system of these animals. Men were more than 50 years of age (44.6%) and wives were mainly between 31 to 50 years old (42%). Primary school was the main grade of instruction. The main labour activity of the head of the family was agriculture (95.4%) and housekeeping for women (97.2%). Raising guinea pigs was mainly driven by the housewife under a family or traditional system. There were 20.4 guinea pigs on average per family, reared regardless of class, sex and age, preferably in the kitchen (88.8%), free (73.8%) or in pools (21.9%). Feeding was based on forages, weeds and kitchen waste. The main diseases reported were ectoparasites (90.1%) and the «plague» (76%). Guinea pigs were used for consumption and sale (71.2%) or only for home consumption (28.2%). Most of producers (96.2%) indicated that they do not have services such as technical assistance, credit, inputs, etc, and 67.5% considered that they would improve their productivity if technical assistance was available

    Transcriptome and metabolome profiling identify factors potentially involved in pro-vitamin A accumulation in cassava landraces

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    Open Access ArticleCassava (Manihot esculenta Crantz) is a predominant food security crop in several developing countries. Its storage roots, rich in carbohydrate, are deficient in essential micronutrients, including provitamin A carotenoids. Increasing carotenoid content in cassava storage roots is important to reduce the incidence of vitamin A deficiency, a public health problem in sub-Saharan Africa. However, cassava improvement advances slowly, mainly due to limited information on the molecular factors influencing β-carotene accumulation in cassava. To address this problem, we performed comparative transcriptomic and untargeted metabolic analyses of roots and leaves of eleven African cassava landraces ranging from white to deep yellow colour, to uncover regulators of carotenoid biosynthesis and accumulation with conserved function in yellow cassava roots. Sequence analysis confirmed the presence of a mutation, known to influence β-carotene content, in PSY transcripts of deep yellow but not of pale yellow genotypes. We identified genes and metabolites with expression and accumulation levels significantly associated with β-carotene content. Particularly an increased activity of the abscisic acid catabolism pathway together with a reduced amount of L-carnitine, may be related to the carotenoid pathway flux, higher in yellow than in white storage roots. In fact, NCED_3.1 was specifically expressed at a lower level in all yellow genotypes suggesting that it could be a potential target for increasing carotenoid accumulation in cassava. These results expand the knowledge on metabolite compositions and molecular mechanisms influencing carotenoid biosynthesis and accumulation in cassava and provide novel information for biotechnological applications and genetic improvement of cassava with high nutritional values

    EpiCass and CassavaNet4Dev advanced bioinformatics workshop

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    Open Access ArticleEpiCass and CassavaNet4Dev are collaborative projects funded by the Swedish Research Council between the Swedish University of Agriculture (SLU) and the International Institute of Tropical Agriculture (IITA). The projects aim to investigate the influence of epigenetic changes on agricultural traits such as yield and virus resistance while also providing African students and researchers with advanced bioinformatics training and opportunities to participate in big data analysis events. The first advanced bioinformatics training workshop took place from May 16th to May 18th, 2022, followed by an online mini-symposium titled "Epigenetics and crop improvement" on May 19th. The symposium featured international speakers covering a wide range of topics related to plant epigenetics, cassava viral diseases, and cassava breeding strategies. A new online and on-site teaching concept was developed for the three-day workshop to ensure maximum student participation across Western, Eastern, and Southern Africa. Initially planned in Nigeria, Kenya, Ethiopia, Tanzania, and Zambia, the workshop ultimately focused on Nigeria, Kenya, and Ethiopia due to a lack of qualified candidates in the other countries. Each classroom hosted 20 to 25 students, with at least one bioinformatician present for support. The classrooms were connected via video conferencing, whereas teachers located in different places in Africa and Europe joined the video stream to conduct teaching sessions. The workshop was divided into theoretical classes and hands-on sessions, where participants could run data analysis with support from online teachers and local bioinformaticians. To enable participants to run guided, CPU and RAM-intensive data analysis workflows and overcome local computing and internet access restrictions, a system of virtual machines (VMs) hosted in the cloud was developed. The teaching platform provided teaching and exercise materials to support the use of the VMs. Although some students could not run heavy data analysis workflows due to unforeseen restrictions in the cloud, these issues were solved. All participants had the opportunity to run the analysis steps independently in the cloud using the protocols hosted on the teaching platform

    p53FamTaG: a database resource of human p53, p63 and p73 direct target genes combining in silico prediction and microarray data

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    <p>Abstract</p> <p>Background</p> <p>The p53 gene family consists of the three genes p53, p63 and p73, which have polyhedral non-overlapping functions in pivotal cellular processes such as DNA synthesis and repair, growth arrest, apoptosis, genome stability, angiogenesis, development and differentiation. These genes encode sequence-specific nuclear transcription factors that recognise the same responsive element (RE) in their target genes. Their inactivation or aberrant expression may determine tumour progression or developmental disease. The discovery of several protein isoforms with antagonistic roles, which are produced by the expression of different promoters and alternative splicing, widened the complexity of the scenario of the transcriptional network of the p53 family members. Therefore, the identification of the genes transactivated by p53 family members is crucial to understand the specific role for each gene in cell cycle regulation. We have combined a genome-wide computational search of p53 family REs and microarray analysis to identify new direct target genes. The huge amount of biological data produced has generated a critical need for bioinformatic tools able to manage and integrate such data and facilitate their retrieval and analysis.</p> <p>Description</p> <p>We have developed the p53FamTaG database (p53 FAMily TArget Genes), a modular relational database, which contains p53 family direct target genes selected in the human genome searching for the presence of the REs and the expression profile of these target genes obtained by microarray experiments. p53FamTaG database also contains annotations of publicly available databases and links to other experimental data.</p> <p>The genome-wide computational search of the REs was performed using PatSearch, a pattern-matching program implemented in the DNAfan tool. These data were integrated with the microarray results we produced from the overexpression of different isoforms of p53, p63 and p73 stably transfected in isogenic cell lines, allowing the comparative study of the transcriptional activity of all the proteins in the same cellular background.</p> <p>p53FamTaG database is available free at <url>http://www2.ba.itb.cnr.it/p53FamTaG/</url></p> <p>Conclusion</p> <p>p53FamTaG represents a unique integrated resource of human direct p53 family target genes that is extensively annotated and provides the users with an efficient query/retrieval system which displays the results of our microarray experiments and allows the export of RE sequences. The database was developed for supporting and integrating high-throughput <it>in silico</it> and experimental analyses and represents an important reference source of knowledge for research groups involved in the field of oncogenesis, apoptosis and cell cycle regulation.</p

    Auxin signaling and vascular cambium formation enables storage metabolism in cassava tuberous roots

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    Open Access Article; Published online: 13 Mar 2021Cassava storage roots are among the most important root crops worldwide and represent one of the most consumed staple foods in Sub-Saharan Africa. The vegetatively propagated tropical shrub can form many starchy tuberous roots from its stem. These storage roots are formed through the activation of secondary root growth processes. However, the underlying genetic regulation of storage root development is largely unknown. Here we report on distinct structural and transcriptional changes occurring during the early phases of storage root development. A pronounced increase in auxin-related transcripts and the transcriptional activation of secondary growth factors, as well as a decrease in gibberellin-related transcripts was observed during the early stages of secondary root growth. This was accompanied by increased cell wall biosynthesis, increased most notably during the initial xylem expansion within the root vasculature. Starch storage metabolism was activated only after the formation of the vascular cambium. The formation of nonlignified xylem parenchyma cells and the activation of starch storage metabolism coincided with increased expression of the KNOX/BEL genes KNAT1, PENNYWISE and POUND-FOOLISH, indicating their importance for proper xylem parenchyma function
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