64 research outputs found

    Unique PFK regulatory property from some mosquito vectors of disease, and from Drosophila melanogaster

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    Effect of F2, 6BP on Aedes aegypti PFK activity. PFK activity was measured at pH = 7.4, 1 mM F6P, 5 mM ATP at several F2, 6BP concentrations (0.01–50 μM). Values are the means ± SEM of three independent experiments. (TIF 466 kb

    Effect of bleaching agents on enamel surface of bovine teeth: a SEM study

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    This study aimed to evaluate changes in the enamel surface of bovine teeth after whitening with exogenous bleaching agents: 10% carbamide peroxide (group 1), 16% carbamide peroxide (group 2) and 35% hydrogen peroxide activated by a light-emitting diode (LED) (group 3). The evaluations were performed by scanning electron microscopy (SEM). Ninety bovine teeth were divided into five groups (n = 18). The bleaching agents 10% and 16% carbamide peroxide were applied for eight hours a day for 14 consecutive days. The third agent, LED-activated 35% hydrogen peroxide, was used four times at seven-day intervals. Each of the four time points consisted of three applications of 10 minutes each. A 37% phosphoric acid solution and artificial saliva were used as positive and negative controls, respectively. The evaluations by SEM showed changes in the enamel surfaces of the specimens. Based on the Mann-Whitney statistical test, the data showed significant differences (p0.05) was observed between groups 1 and 3. Based on these results, it can be concluded that bleaching agents can cause changes in the structure of tooth enamel and that these changes are related to the concentration and the duration of contact with the tooth surface

    Superação da dormência e armazenamento de sementes de Ornithogalum arabicum L.

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    Ornithogalum arabicum L. é uma espécie exótica, conhecida popularmente como estrela - de - Belém e utilizada principalmente para o paisagismo. Suas sementes possuem germinação muito lenta e desuniforme devido à presença de dormência. Este estudo objetivou avaliar os tratamentos mais eficientes na superação da dormência e o efeito do armazenamento nas sementes de O. arabicum. Foram avaliados os seguintes métodos de superação da dormência: escarificação química com ácido sulfúrico por 2, 5 e 10 minutos; imersão em água aquecida por 2, 5 e 10 minutos; escarificação mecânica (sem embebição e com embebição de água destilada por 12 e 24 horas) no hilo, no hilo e extremidade oposta ao hilo e na lateral da semente, totalizando dezesseis tratamentos. As sementes foram armazenadas em temperatura ambiente durante seis meses e submetidas ao tratamento de superação de dormência mais eficaz e avaliadas pelos testes de germinação e de vigor. Adotou-se o delineamento inteiramente casualizado nos testes de superação de dormência e para o armazenamento foi utilizado um fatorial 2 x 2 (escarificação x armazenamento). Conclui-se que as sementes de O. arabicum apresentam dormência por tegumento duro e esta é superada com a escarificação mecânica realizada no hilo e na extremidade oposta ao hilo seguida de embebição por 12 e 24 horas. O armazenamento por seis meses supera a dormência tegumentar nas sementes

    Activation of Human CD11b+ B1 B-Cells by Trypanosoma cruzi-Derived Proteins Is Associated With Protective Immune Response in Human Chagas Disease

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    B-cells mediate humoral adaptive immune response via the production of antibodies and cytokines, and by inducing T-cell activation. These functions can be attributed to distinct B-cell subpopulations. Infection with Trypanosoma cruzi, the causative agent of Chagas disease, induces a polyclonal B-cell activation and lytic antibody production, critical for controlling parasitemia. Individuals within the chronic phase of Chagas disease may remain in an asymptomatic form (indeterminate), or develop severe cardiomyopathy (cardiac form) that can lead to death. Currently, there is no effective vaccine to prevent Chagas disease, and no treatment to halt the development of the cardiomyopathy once it is installed. The pathology associated with cardiac Chagas disease is a result of an inflammatory reaction. Thus, discovering characteristics of the host's immune response that favor the maintenance of favorable heart function may unveil important immunotherapeutic targets. Given the importance of B cells in antibody production and parasite control, we investigated T. cruzi-derived antigenic fractions responsible for B-cell activation and whether frequencies and functional characteristics of B-cell subpopulations are associated with different clinical outcomes of human Chagas disease. We stimulated cells from indeterminate (I) and cardiac (C) Chagas patients, as well as non-infected individuals (NI), with T. cruzi-derived protein- (PRO), glycolipid- (GCL) and lipid (LIP)-enriched fractions and determined functional characteristics of B-cell subpopulations. Our results showed that the frequency of B-cells was similar amongst groups. PRO, but not GCL nor LIP, led to an increased frequency of B1 B-cells in I, but not C nor NI. Although stimulation with PRO induced higher TNF expression by B1 B-cells from C and I, as compared to NI, it induced expression of IL-10 in cells from I, but not C. Stimulation with PRO induced an increased frequency of the CD11b+ B1 B-cell subpopulation, which was associated with better cardiac function. Chagas patients displayed increased IgM production, and activation of gamma-delta T-cells, which have been associated with B1 B-cell function. Our data showed that PRO activates CD11b+ B1 B-cells, and that this activation is associated with a beneficial clinical status. These findings may have implications in designing new strategies focusing on B-cell activation to prevent Chagas disease cardiomyopathy

    Telessaúde Covid: caracterização sociodemográfica, clínico-epidemiológica e indicadores do telemonitoramento em Viçosa-MG

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    Em 2020, a Universidade Federal de Viçosa e a Gestão Municipal implementaram o projeto de extensão Telessaúde Covid para o enfrentamento da pandemia. O objetivo é fazer uma análise descritiva dos quatorze meses de atuação do projeto. Realizou-se análise descritiva da caracterização sociodemográfica, clínico-epidemiológica e indicadores do serviço. Foram atendidos 6.898 pacientes, predominando o gênero feminino e adultos jovens. Os sinais e sintomas mais frequentes foram cefaleia, tosse, coriza, dor de garganta, dor muscular e febre. O RT-PCR foi o teste realizado pela maioria e 31,6% dos pacientes foram positivos. O serviço concluiu o encerramento de 91,5% dos atendimentos. O Telessaúde Covid foi relevante para o contingenciamento da Covid-19, com número expressivo de atendimentos, e contemplou a missão social da universidade pública, transformando o modelo assistencial e reorientando o processo de formação e ação profissional de estudantes e profissionais de saúde

    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

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    ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

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    Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ
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