45 research outputs found

    High levels of blood pressure among Brazilian overweight and obese children and adolescents

    Get PDF
    Introdução: A hipertensão arterial (AH) é um problema crescente no mundo e traz várias consequências para a saúde. Numerosos levantamentos mostram que o risco de AH é maior em indivíduos com sobrepeso e obesos do que nos eutróficos. Por isso, este estudo tem como objetivo avaliar a prevalência de hipertensão arterial em crianças e adolescentes portadores de sobrepeso e obesidade. Métodos: Estudo transversal retrospectivo com crianças e adolescentes de dois serviços de saúde em diferentes regiões do Brasil e perfis socioeconômicos distintos. Todas as crianças e adolescentes atendidos entre 1998 e 2020, com idades entre 5 e 17 anos, com escore z de índice de massa corporal superior a +1 foram incluídos no estudo. A pressão arterial foi medida uma vez com o paciente deitado e em repouso. As diretrizes da Academia Americana de Pediatria foram usadas para classificar os níveis de pressão arterial do paciente. Resultados: Foram avaliados 691 pacientes (49% do sexo masculino). As prevalências de hipertensãoarterial entre indivíduos com sobrepeso e obesidade foram de 38,8% e 51,5% (p = 0,002), respectivamente. Além disso, os indivíduos obesos tinham 1,67 vezes mais chances de ter hipertensão em comparação com os portadores de sobrepeso. Os homens apresentaram maior prevalência de hipertensão arterial (52,1% vs. 43,3%; p = 0,002) e foram 1,3 vezes mais propensos a ter valores mais elevados de pressão arterial. Conclusão: A prevalência de hipertensão arterial em dois ambulatórios pediátricos foi elevada entre crianças e adolescentes portadores de sobrepeso e obesidade. Homens e indivíduos com obesidade tiveram risco significativamente maior de hipertensão.Background: Arterial hypertension (AH) is a growing problem globally, bringing various health consequences. Numerous surveys show that the risk of AH is higher in overweight and obese individuals than in eutrophic ones. However, the number of data that investigates blood pressure in obese pediatric populations is still small. Therefore, this study aims to assess the prevalence of hypertension in overweight and obese children and adolescents. Methods:Retrospective cross-sectional study with children and adolescents from two health services in different regions of Brazil and distinct socioeconomic profiles. All children and adolescents seen between 1998-2020, aged 5-17 years, with a body mass index greater than +1 standard deviation (Z-score), were enrolled in the study. Blood pressure was measured once with the patient lying down and at rest. American Academy of Pediatrics guidelines were used to classify the patient’s blood pressure levels. Results: 691 patients were evaluated (49% male). Of these, 47.6% had hypertension. The prevalences of hypertension among overweight and obese subjects were 38.8% and 51.5% (p = 0.002), respectively. In addition, obese people were 1.67 times more likely to have hypertension than overweight people. Males had a higher prevalence of hypertension (52.1% vs. 43.3%; p = 0.002) and were 1.3 times more likely to have high blood pressure values. Conclusion: The prevalence of hypertension was high in overweightand obese children and adolescents from two pediatric outpatient clinics. Males and subjects with obesity were at significantly higher risk of having hypertension

    Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

    Get PDF
    Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types

    Mapping density, diversity and species-richness of the Amazon tree flora

    Get PDF
    Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Consistent patterns of common species across tropical tree communities

    Get PDF
    Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

    Get PDF
    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
    corecore