14 research outputs found

    Pervasive gaps in Amazonian ecological research

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    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

    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 understanding 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,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 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 underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities 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 organism 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 neglected 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 lost

    Sarcomas de alto grau: estudo retrospectivo de 131 casos

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    OBJETIVO: Relatar as características clínicas dos sarcomas de partes moles de alto grau e apresentar a experiência do Hospital Araújo Jorge no tratamento destes sarcomas. MÉTODO: Análise retrospectiva dos casos de sarcoma de alto grau em adultos admitidos no Hospital Araújo Jorge (HAJ) entre 1996 e 2000. Idade, sexo, características anátomo-patológicas (tamanho e tipo histológico), localização, tratamentos oncológicos realizados (cirurgias de preservação de órgãos e membros, margens, quimioterapia, radioterapia), recorrência local, recorrência distante e sobrevida foram estudados. Análise descritiva, curvas de Kaplan-Meier, log-rank test e teste ÷² foram usados quando pertinentes. RESULTADOS: Foram registrados 235 pacientes com sarcomas de partes moles entre 1996 - 2000, sendo que 131 eram de alto grau. A média de idade foi de 47,2 anos. O tipo histológico não foi determinado em 23,7% dos casos. O tipo mais freqüente foi o leiomiossarcoma (13,7%), seguido do sarcoma sinovial (10,7%) e rabdomiossarcoma (9,2%). O tamanho mediano foi de 10 cm (2-48 cm). A distribuição nos estádios II,III e IV foi de 15%, 55% e 30%, respectivamente. Nos pacientes com estádios II e III, a margem cirúrgica adequada foi obtida em 51,9% dos pacientes. Radioterapia e quimioterapia adjuvantes foram indicadas em 33,7% e 26,1% dos casos, respectivamente. As recorrências locais e distantes ocorreram em 31,5% e 34,8% dos pacientes, respectivamente. A sobrevida global em 5 anos foi 61,8%. CONCLUSÃO: A maioria dos pacientes atendidos no HAJ é portadora de lesões localmente avançadas, volumosas ou com metástase ao diagnóstico. Os pacientes apresentaram evolução adversa, com altas taxas de recorrência local e distante

    Valor prognóstico da citologia positiva no lavado peritoneal de pacientes com câncer gástrico ressecável Prognostic role of positive peritoneal cytology in patients with resectable gastric cancer

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    OBJETIVO: Avaliar o valor prognóstico do lavado peritoneal positivo em pacientes com câncer gástrico sem sinais de disseminação peritoneal ou hematogênica. MÉTODOS: Foram avaliados os pacientes com adenocarcinoma gástrico tratados com operação de intenção curativa. O lavado peritoneal foi classificado como positivo ou negativo para células neoplásicas. Foram obtidos dados demográficos, performance status, histológicos e tipo de operação realizada. Os resultados foram estatisticamente comparados e considerados significantes para valores de pOBJECTIVE: To evaluate the prognostic value of positive peritoneal lavage in patients with gastric cancer without signs of peritoneal or hematogenous spread. METHODS: We evaluated patients with gastric adenocarcinoma treated with curative intent operation. The peritoneal lavage was classified as positive or negative for neoplastic cells. We obtained demographics, performance status, histology and type of surgery. The results were statistically compared and were considered significant for values of p <0.05. RESULTS: We included 72 patients with gastric adenocarcinoma. During a mean follow up of 26 months (one to 39 months) we observed 20 local or distant recurrences and 21 deaths. Only the presence of lymph node metastases and the need for resection of adjacent organs were associated with a significant reduction in relapse-free survival. There was a significant reduction in overall survival in patients with angio-lymphatic invasion, lymph node metastasis, requiring resection of multiple organs, need for total gastrectomy and greater invasion of the gastric wall. The presence of tumor cells in the peritoneal cavity was associated with worse overall survival, but without statistical significance. CONCLUSION: There was no statistically significant associations between positive peritoneal citology and recurrence-free survival or overall survival among patients with resectable gastric cancer

    Association of the <i>p75<sup>NTR</sup></i> Ser205Leu Polymorphism with Asymptomatic HTLV-1 Infection

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    Genetic variations in components of the immune response seem to be an important factor that contributes to the manifestation of symptoms of some diseases related to HTLV-1 infection. Nerve growth factor (NGF) and the p75 neurotrophin receptor (p75NTR) are related to the maintenance of neurons and the activation of the immune response. In this study, we evaluated the association of the NGF -198C/T, NGF Ala35Val, and p75NTR Ser205Leu polymorphisms with HTLV-1 infection and plasma cytokine levels in 166 samples from individuals infected with HTLV-1 (59 symptomatic and 107 asymptomatic). The genotyping and quantification of the proviral load were performed by real-time PCR, and cytokine levels were measured by ELISA. The NGF -198C/T and NGF Ala35Val polymorphisms were not associated with HTLV-1 infection. The frequency of the Ser/Leu genotype of p75NTR Ser205Leu was more frequent in the control group (p = 0.0385), and the Ser/Leu genotype and allele Leu were more frequent among the asymptomatic (p p p Ser/Leu genotype (p = 0.0797) had lower levels of proviral load and higher levels of TNF-α (p = 0.0507). Based on the results obtained, we conclude that the p75NTR Ser205Leu polymorphism may be associated with reduced susceptibility to HTLV-1 infection, a lower risk of developing symptoms, including HAM, and better infection control

    A proposal of Brazilian Society of Surgical Oncology for standardizing cytoreductive surgery plus hypertermic intraperitoneal chemotherapy procedures in Brazil: pseudomixoma peritonei, appendiceal tumors and malignant peritoneal mesothelioma

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    ABSTRACT Cytoreductive surgery plus hypertermic intraperitoneal chemotherapy has emerged as a major comprehensive treatment of peritoneal malignancies and is currently the standard of care for appendiceal epithelial neoplasms and pseudomyxoma peritonei syndrome as well as malignant peritoneal mesothelioma. Unfortunately, there are some worldwide variations of the cytoreductive surgery and hypertermic intraperitoneal chemotherapy techniques since no single technique has so far demonstrated its superiority over the others. Therefore, standardization of practices might enhance better comparisons between outcomes. In these settings, the Brazilian Society of Surgical Oncology considered it important to present a proposal for standardizing cytoreductive surgery plus hypertermic intraperitoneal chemotherapy procedures in Brazil, with a special focus on producing homogeneous data for the developing Brazilian register for peritoneal surface malignancies
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