15 research outputs found

    Tree component analysis in a savanna-forest ecotone area of Minas Gerais State, Brazil

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    Ecotones are transition areas characterized by environmental complexity and high biodiversity. In this sense, carrying out a floristic survey and characterization of each phytoecological region is necessary. Thus, we analyzed the floristic composition, horizontal and vertical structure, and dispersal syndromes of the woody community in an ecotone of cerrado sensu stricto and seasonal deciduous forest. Likewise, we proceeded with the floristic similarity analysis to evaluate the study area’s similarities to the vegetation of cerrado sensu stricto and seasonal deciduous forest. A total of 919 individuals from 19 families, 43 genera, and 49 species were sampled. The tree community has an average height of 4.12 m, a species diversity of 3.03 nats.ind-1, and a Pielou equitability index of 0.77. The predominant dispersion syndrome was anemochory. The vegetation formed floristic groups with the cerrado sensu stricto. The environmental gradient that determines the occurrence of transition vegetation makes each remnant unique in terms of species and structure, demonstrating the importance of these areas for the biodiversity conservation.Ecotones are transition areas characterized by environmental complexity and high biodiversity. In this sense, carrying out a floristic survey and characterization of each phytoecological region is necessary. Thus, we analyzed the floristic composition, horizontal and vertical structure, and dispersal syndromes of the woody community in an ecotone of Cerrado Sensu Stricto and seasonal deciduous forest. Likewise, we proceeded with the floristic similarity analysis to evaluate the study area’s similarities to the vegetation of cerrado Sensu Stricto and seasonal deciduous forest. A total of 919 individuals from 19 families, 43 genera, and 49 species were sampled. The tree community has an average height of 4.12 m, a species diversity of 3.03 nats ind‑1, and a Pielou equitability index of 0.77. The predominant dispersion syndrome was anemochory. The vegetation formed floristic groups with the Cerrado Sensu Stricto. The environmental gradient that determines the occurrence of transition vegetation makes each remnant unique in terms of species and structure, demonstrating the importance of these areas for the biodiversity conservation

    Relações estruturais e de diversidade de uma floresta ripária em unidade de conservação e sua zona de amortecimento

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    O objetivo do estudo foi analisar a estrutura, diversidade e heterogeneidade do componente arbóreo de uma Mata Ripária em uma Unidade de Conservação. Além disso, comparar a estrutura desta vegetação com a Mata Ripária da zona de amortecimento. A área de estudo está situada no Parque Estadual Lapa Grande, Minas Gerias (Brasil). O inventário florestal foi realizado na unidade de conservação (UC) e na sua zona de amortecimento. Como critério de inclusão, mensurou-se todos os indivíduos com DAP ≥ 3 cm, bem como a sua altura total. Processou-se os parâmetros fitossociológicos e florísticos da vegetação, e empreendeu-se a análise de correspondência distendida (DCA), análise de agrupamento de “cluster” do coeficiente de similaridade de Horn e o coeficiente de Jaccard. Foram amostrados 1.426 indivíduos dentro da unidade de conservação e 944 indivíduos para a zona de amortecimento. O índice de diversidade de Shannon encontrado para a UC foi de 4,61 nats.ind-1, a equabilidade de Pielou de 0,85. Em relação a zona de amortecimento, os valores de diversidade foram de 3,79 nats.ind-1, equabilidade de 0,82. Foi observado uma diferença significativa entre as diversidades das duas áreas, com valores de t= 10,98 para p < 0,001. Ao realizar a similaridade das parcelas através da análise de Cluster observa-se que as parcelas não formaram grupos distintos, a DCA mostrou a formação de fortes gradientes florísticos entre os ambientes. Conclui-se que há uma heterogeneidade entre as áreas. Além disso, as áreas da unidade de conservação e sua zona de amortecimento desempenham um papel de importância para conservação

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Relações estruturais e de diversidade de uma floresta ripária em unidade de conservação e sua zona de amortecimento

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    The aim of the study was to analyze the structure, diversity and heterogeneity of the arboreal component of a Riparian Forest in a Conservation Unit. In addition, to compare the structure of this vegetation with the Mata Ripária of the buffer zone. The study area is located in the Lapa Grande State Park, Minas Gerais State (Brazil). The forest inventory was carried out in the conservation unit and in its buffer zone. As a criterion, all individuals with a DBH ≥ 3 cm were measured, as well as their total height. The phytosociological and floristic parameters of the vegetation were processed, and the extendedcorrespondence analysis (DCA), cluster analysis of the Horn's similarity and the Jaccard coefficient were performed. We sampled 1,426 individuals in the interior and 944 individuals in the buffer zone. The diversity index of Shannon reached to the conservation unit was 4.61 nats.ind-1, the Pielou equability of 0.85. In relation to the buffer zone, the values of diversity were 3.79 nats.ind-1, equability of 0.82. A significant difference was observed between the diversities of the two areas, with values of t = 10.98 for p <0.001. When realizing the similarity of the plots through Cluster analysis it is observed that the plots did not formed distinctives groups, the DCA showed the formation of strong floristic gradients between the environments. We conclude that there is a heterogeneity between the areas. In addition, the areas of the conservation unit and its buffer zone play a major role for conservation.O objetivo do estudo foi analisar a estrutura, diversidade e heterogeneidade do componente arbóreo de uma Mata Ripária em uma Unidade de Conservação. Além disso, comparar a estrutura desta vegetação com a Mata Ripária da zona de amortecimento. A área de estudo está situada no Parque Estadual Lapa Grande, Minas Gerias (Brasil). O inventário florestal foi realizado na unidade de conservação (UC) e na sua zona de amortecimento. Como critério de inclusão, mensurou-se todos os indivíduos com DAP ≥ 3 cm, bem como a sua altura total. Processou-se os parâmetros fitossociológicos e florísticos da vegetação, e empreendeu-se a análise de correspondência distendida (DCA), análise de agrupamento de “cluster” do coeficiente de similaridade de Horn e o coeficiente de Jaccard. Foram amostrados 1.426 indivíduos dentro da unidade de conservação e 944 indivíduos para a zona de amortecimento. O índice de diversidade de Shannon encontrado para a UC foi de 4,61 nats.ind-1, a equabilidade de Pielou de 0,85. Em relação a zona de amortecimento, os valores de diversidade foram de 3,79 nats.ind-1, equabilidade de 0,82. Foi observado uma diferença significativa entre as diversidades das duas áreas, com valores de t= 10,98 para p < 0,001. Ao realizar a similaridade das parcelas através da análise de Cluster observa-se que as parcelas não formaram grupos distintos, a DCA mostrou a formação de fortes gradientes florísticos entre os ambientes. Conclui-se que há uma heterogeneidade entre as áreas. Além disso, as áreas da unidade de conservação e sua zona de amortecimento desempenham um papel de importância para conservação

    Unseen rare tree species in southeast Brazilian forests: a species abundance distribution approach

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    Rarity is an important aspect of biodiversity often neglected in ecological studies. Species abundance distributions (SADs) are useful tools to describe patterns of commonness–rarity in ecological communities. Most studies assume field observa- tions of species relative abundances are approximately equal to their true relative abundances, thus dismissing the potential for, and importance of unseen rare species. Here, we adopted the approach proposed by Chao et al. (Ecol, 96:1189–1201, 2015) to estimate the number and abundance of unseen species, and thus the true SADs, for tree species in 48 forest sites in Minas Gerais state, Brazil (4 rainforests, 35 semideciduous forests, and 9 deciduous forests). Also, we assessed the correla- tions between both unseen and rare species and sampling protocol and environment characteristics (climate, terrain, terrain heterogeneity). We found estimated true SADs invariably had higher species richness values than observed in the surveys, due to the increase in rare species. We estimate that up to 55.6% of tree species per site were unseen (8.5–55.6%), with an average of 26.6%. The estimated percentage of rare species per site was between 31.9% and 72.8%, with an average of 57.78%. We found rarity to be most strongly correlated with the percentage of unidentified trees, local terrain conditions and hetero- geneity at site-level. Semideciduous forest and rainforest had similar higher percentages of unseen species (c. 27.2%) when compared to deciduous forests, probably due to the relatively higher local heterogeneity of these forests, which may provide more niches for rare species. Future studies should consider estimating true species abundances to better assess biodiversity

    Respiratory support in patients with severe COVID-19 in the International Severe Acute Respiratory and Emerging Infection (ISARIC) COVID-19 study: a prospective, multinational, observational study

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    Background: Up to 30% of hospitalised patients with COVID-19 require advanced respiratory support, including high-flow nasal cannulas (HFNC), non-invasive mechanical ventilation (NIV), or invasive mechanical ventilation (IMV). We aimed to describe the clinical characteristics, outcomes and risk factors for failing non-invasive respiratory support in patients treated with severe COVID-19 during the first two years of the pandemic in high-income countries (HICs) and low middle-income countries (LMICs). Methods: This is a multinational, multicentre, prospective cohort study embedded in the ISARIC-WHO COVID-19 Clinical Characterisation Protocol. Patients with laboratory-confirmed SARS-CoV-2 infection who required hospital admission were recruited prospectively. Patients treated with HFNC, NIV, or IMV within the first 24 h of hospital admission were included in this study. Descriptive statistics, random forest, and logistic regression analyses were used to describe clinical characteristics and compare clinical outcomes among patients treated with the different types of advanced respiratory support. Results: A total of 66,565 patients were included in this study. Overall, 82.6% of patients were treated in HIC, and 40.6% were admitted to the hospital during the first pandemic wave. During the first 24 h after hospital admission, patients in HICs were more frequently treated with HFNC (48.0%), followed by NIV (38.6%) and IMV (13.4%). In contrast, patients admitted in lower- and middle-income countries (LMICs) were less frequently treated with HFNC (16.1%) and the majority received IMV (59.1%). The failure rate of non-invasive respiratory support (i.e. HFNC or NIV) was 15.5%, of which 71.2% were from HIC and 28.8% from LMIC. The variables most strongly associated with non-invasive ventilation failure, defined as progression to IMV, were high leukocyte counts at hospital admission (OR [95%CI]; 5.86 [4.83-7.10]), treatment in an LMIC (OR [95%CI]; 2.04 [1.97-2.11]), and tachypnoea at hospital admission (OR [95%CI]; 1.16 [1.14-1.18]). Patients who failed HFNC/NIV had a higher 28-day fatality ratio (OR [95%CI]; 1.27 [1.25-1.30]). Conclusions: In the present international cohort, the most frequently used advanced respiratory support was the HFNC. However, IMV was used more often in LMIC. Higher leucocyte count, tachypnoea, and treatment in LMIC were risk factors for HFNC/NIV failure. HFNC/NIV failure was related to worse clinical outcomes, such as 28-day mortality. Trial registration This is a prospective observational study; therefore, no health care interventions were applied to participants, and trial registration is not applicable

    Association of Country Income Level With the Characteristics and Outcomes of Critically Ill Patients Hospitalized With Acute Kidney Injury and COVID-19

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    Introduction: Acute kidney injury (AKI) has been identified as one of the most common and significant problems in hospitalized patients with COVID-19. However, studies examining the relationship between COVID-19 and AKI in low- and low-middle income countries (LLMIC) are lacking. Given that AKI is known to carry a higher mortality rate in these countries, it is important to understand differences in this population. Methods: This prospective, observational study examines the AKI incidence and characteristics of 32,210 patients with COVID-19 from 49 countries across all income levels who were admitted to an intensive care unit during their hospital stay. Results: Among patients with COVID-19 admitted to the intensive care unit, AKI incidence was highest in patients in LLMIC, followed by patients in upper-middle income countries (UMIC) and high-income countries (HIC) (53%, 38%, and 30%, respectively), whereas dialysis rates were lowest among patients with AKI from LLMIC and highest among those from HIC (27% vs. 45%). Patients with AKI in LLMIC had the largest proportion of community-acquired AKI (CA-AKI) and highest rate of in-hospital death (79% vs. 54% in HIC and 66% in UMIC). The association between AKI, being from LLMIC and in-hospital death persisted even after adjusting for disease severity. Conclusions: AKI is a particularly devastating complication of COVID-19 among patients from poorer nations where the gaps in accessibility and quality of healthcare delivery have a major impact on patient outcomes

    Respiratory support in patients with severe COVID-19 in the International Severe Acute Respiratory and Emerging Infection (ISARIC) COVID-19 study: a prospective, multinational, observational study

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    Background: Up to 30% of hospitalised patients with COVID-19 require advanced respiratory support, including high-flow nasal cannulas (HFNC), non-invasive mechanical ventilation (NIV), or invasive mechanical ventilation (IMV). We aimed to describe the clinical characteristics, outcomes and risk factors for failing non-invasive respiratory support in patients treated with severe COVID-19 during the first two years of the pandemic in high-income countries (HICs) and low middle-income countries (LMICs). Methods: This is a multinational, multicentre, prospective cohort study embedded in the ISARIC-WHO COVID-19 Clinical Characterisation Protocol. Patients with laboratory-confirmed SARS-CoV-2 infection who required hospital admission were recruited prospectively. Patients treated with HFNC, NIV, or IMV within the first 24 h of hospital admission were included in this study. Descriptive statistics, random forest, and logistic regression analyses were used to describe clinical characteristics and compare clinical outcomes among patients treated with the different types of advanced respiratory support. Results: A total of 66,565 patients were included in this study. Overall, 82.6% of patients were treated in HIC, and 40.6% were admitted to the hospital during the first pandemic wave. During the first 24 h after hospital admission, patients in HICs were more frequently treated with HFNC (48.0%), followed by NIV (38.6%) and IMV (13.4%). In contrast, patients admitted in lower- and middle-income countries (LMICs) were less frequently treated with HFNC (16.1%) and the majority received IMV (59.1%). The failure rate of non-invasive respiratory support (i.e. HFNC or NIV) was 15.5%, of which 71.2% were from HIC and 28.8% from LMIC. The variables most strongly associated with non-invasive ventilation failure, defined as progression to IMV, were high leukocyte counts at hospital admission (OR [95%CI]; 5.86 [4.83–7.10]), treatment in an LMIC (OR [95%CI]; 2.04 [1.97–2.11]), and tachypnoea at hospital admission (OR [95%CI]; 1.16 [1.14–1.18]). Patients who failed HFNC/NIV had a higher 28-day fatality ratio (OR [95%CI]; 1.27 [1.25–1.30]). Conclusions: In the present international cohort, the most frequently used advanced respiratory support was the HFNC. However, IMV was used more often in LMIC. Higher leucocyte count, tachypnoea, and treatment in LMIC were risk factors for HFNC/NIV failure. HFNC/NIV failure was related to worse clinical outcomes, such as 28-day mortality. Trial registration This is a prospective observational study; therefore, no health care interventions were applied to participants, and trial registration is not applicable

    Thrombotic and hemorrhagic complications of COVID-19 in adults hospitalized in high-income countries compared with those in adults hospitalized in low- and middle-income countries in an international registry

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    Background: COVID-19 has been associated with a broad range of thromboembolic, ischemic, and hemorrhagic complications (coagulopathy complications). Most studies have focused on patients with severe disease from high-income countries (HICs). Objectives: The main aims were to compare the frequency of coagulopathy complications in developing countries (low- and middle-income countries [LMICs]) with those in HICs, delineate the frequency across a range of treatment levels, and determine associations with in-hospital mortality. Methods: Adult patients enrolled in an observational, multinational registry, the International Severe Acute Respiratory and Emerging Infections COVID-19 study, between January 1, 2020, and September 15, 2021, met inclusion criteria, including admission to a hospital for laboratory-confirmed, acute COVID-19 and data on complications and survival. The advanced-treatment cohort received care, such as admission to the intensive care unit, mechanical ventilation, or inotropes or vasopressors; the basic-treatment cohort did not receive any of these interventions. Results: The study population included 495,682 patients from 52 countries, with 63% from LMICs and 85% in the basic treatment cohort. The frequency of coagulopathy complications was higher in HICs (0.76%-3.4%) than in LMICs (0.09%-1.22%). Complications were more frequent in the advanced-treatment cohort than in the basic-treatment cohort. Coagulopathy complications were associated with increased in-hospital mortality (odds ratio, 1.58; 95% CI, 1.52-1.64). The increased mortality associated with these complications was higher in LMICs (58.5%) than in HICs (35.4%). After controlling for coagulopathy complications, treatment intensity, and multiple other factors, the mortality was higher among patients in LMICs than among patients in HICs (odds ratio, 1.45; 95% CI, 1.39-1.51). Conclusion: In a large, international registry of patients hospitalized for COVID-19, coagulopathy complications were more frequent in HICs than in LMICs (developing countries). Increased mortality associated with coagulopathy complications was of a greater magnitude among patients in LMICs. Additional research is needed regarding timely diagnosis of and intervention for coagulation derangements associated with COVID-19, particularly for limited-resource settings
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