10 research outputs found

    Avaliação da toxicidade da nanopartícula de óxido de zinco em microcrustáceo Daphnia magna, bactéria bioluminescente Aliivibrio fischeri, células de neuroblastoma murino e sementes de alface Lactuca sativa

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    TCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Biológicas. Biologia.A nanotecnologia é a ciência que estuda e desenvolve materiais cuja escala extremamente pequena permite um aproveitamento diferenciado dos mesmos. Porém ainda não ainda há regulamentação específica para o uso e descarte de nanopartículas (NP) no Brasil. A nanopartícula de óxido de zinco (NP ZnO) tem chamado atenção devido ao seu uso em cosméticos que possuem fator de proteção solar, entre outras aplicações. Para melhor conhecimento dos possíveis danos causados por essa NP, ao meio ambiente e à saúde, optou-se por realizar testes de toxicologia ambiental em microcrustáceo Daphnia magna, bactéria Aliivibrio fischeri, célula de neuroblastoma murino (N2A) e semente de alface (Lactuca sativa). Através de MET, as NP ZnO observadas possuíam tamanhos entre 20 e 50 nm; a área superficial, que foi obtida através do método BET, foi 4,766 m².g-1. Além disso, avaliou-se o potencial zeta e o tamanho hidrodinâmico das NP ZnO nos diferentes meios de teste, o que indicou baixa estabilidade em suspensão. Para o teste agudo com D. magna, obteve-se uma CE50,48h de 4,2 ± 0,7 mg.L-1, sendo classificada com tóxica. Já no teste crônico com D. magna, foram observados efeitos sobre a longevidade, reprodução e crescimento das Daphnia, sendo obtidas, respectivamente, CEO igual a 1,0; 0,5 e; 1,0 mg.L-1. O ensaio com A. fischeri apresentou CE50,15min de 73,55 mg.L-1 e CE50,30min de 23,88 mg.L-1. No ensaio MTT com células N2A, o efeito da nanopartícula de óxido de zinco sobre a viabilidade celular se mostrou dose-dependente, apresentando uma CE50,24h igual a 0,9 ± 0,02 mg.L-1. Os resultados da quantificação do zinco em cada amostra, evidenciaram que, exceto para os testes de crescimento das plântulas de alface e de inibição da bioluminescência de A. fischeri, todas as amostras apresentaram quantidades de zinco total abaixo do limite permitido na legislação brasileira e, ainda assim, causaram efeitos tóxicos sobre os organismos testados

    The complete genome sequence of Chromobacterium violaceum reveals remarkable and exploitable bacterial adaptability

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    Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals (i) extensive alternative pathways for energy generation, (ii) ≈500 ORFs for transport-related proteins, (iii) complex and extensive systems for stress adaptation and motility, and (iv) wide-spread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for the detoxification of xenobiotics that may have biotechnological applications

    Influência da prática do yoga sobre os sintomas do climatério

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    Introdução: Yoga vem sendo praticado há mais de três mil anos e atualmente seu conjunto de técnicas de controle do corpo e da mente tem sido adotado por milhares de pessoas em todo o mundo. Um número crescente de estudos têm atribuído ao yoga benefícios significativos para a reabilitação da saúde do indivíduo. Na mulher, o processo de envelhecimento é marcado pela suspensão da atividade folicular ovariana (menopausa) durante o período do climatério, este caracterizado por uma série de alterações fisiológicas e neuroendócrinas que podem ser acompanhadas por sintomas desconfortáveis e muitas vezes debilitantes. Objetivo: o objetivo deste estudo é investigar os efeitos psicofisiológicos da prática regular do yoga em mulheres que apresentam sintomas do climatério. Método: Noventa mulheres na faixa etária entre 45 e 65 anos, já em menopausa há pelo menos um ano foram divididas em três grupos: Grupo Controle (não participaram das atividades, n = 19), Grupo ginástica suave (2 vezes por semana, n = 31) e Grupo yoga (2 vezes por semana, n = 40). Todas as participantes foram avaliadas antes e ao final do período da intervenção (12 semanas) através dos inventários de síndrome climatérica (MRS: Menopause Rating Scale), depressão (Inventário de Depressão de Beck), estresse (Inventário de Sintomas de Stress para Adultos de Lipp) e medidas de cortisol salivar. O protocolo de pesquisa foi aprovado pelo comitê de ética (582/11/CEP/HUOL, CAAE 09930.000.294-11). Resultados: Nossos resultados mostraram que as voluntárias que praticaram yoga apresentaram redução do índice referente aos sintomas climatéricos após 12 semanas de prática (8,65 ± 1,05) em relação as voluntárias que praticaram ginástica suave (15,13 ± 1,24) e ao grupo controle que não praticou nenhuma atividade (18,58 ± 2,59), esta redução indica uma melhora nos sintomas. Além disso, os grupos ginástica suave (11,65 ± 0,95) e yoga (9,85 ± 1,17) apresentaram uma melhora significativa com relação aos níveis de depressão quando comparados ao grupo controle (18,95 ± 2,66). Após 12 semanas de pratica, os níveis de estresse também foram reduzidos no grupo yoga (0,55 ± 0,14) com relação ao controle (1,74 ± 0,31) e grupo ginástica suave (1,35 ±  0,19). Conclusões: Nossos resultados mostram que a prática deyogapode ser eficazna redução dos sintomas do climatério, além de diminuir os níveis de estresse dessas mulheres, podendo ser considerado como terapia alternativa para o manejo dos sintomas da menopausa

    Hatha Yoga practice decreases menopause symptoms and improves quality of life: a randomized controlled trial

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    Objectives: Yoga practice includes a group of specific psychophysical techniques. Although previous studies showed beneficial effects of yoga for health and rehabilitation, improving quality of life, there are few studies on the possible therapeutic application of yoga during the climacteric period. The purpose of this study was to investigate the psychophysiological effects of Hatha Yoga regular practice in post-menopausal women. Methods: Eighty-eight post-menopausal women volunteered for this 12-week trial. They were randomly assigned to one of three groups: control (no intervention), exercise, and yoga. Questionnaires were applied in order to evaluate climacteric syndrome (Menopause Rating Scale), stress (Lipp Stress Symptom Inventory), quality of life (Brief World Health Organization Quality of Life), depression (Beck Depression Inventory) and anxiety (State/Trait Anxiety Inventories). Physiological changes were evaluated through hormone levels (cortisol, FSH, LH, progesterone and estradiol). Results: At 12 weeks, yoga practitioners showed statistically lower scores for menopausal symptoms, stress levels and depression symptoms, as well as significantly higher scores in quality of life when compared to control and exercise groups. Only control group presented a significant increase in cortisol levels. The yoga and exercise groups showed decreased levels of FSH and LH when compared to control group. Conclusions: These results suggest that yoga promotes positive psychophysiological changes in post-menopausal women and may be applied as a complementary therapy towards this population

    Structural analysis of Dioclea lasiocatpa lectin : a C6 cells apoptosis-inducing protein

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    Lectins are multidomain proteins that specifically recognize various carbohydrates. The structural characterization of these molecules is crucial in understanding their function and activity in systems and organisms. Most cancer cells exhibit changes in glycosylation patterns, and lectins may be able to recognize these changes. In this work, Dioclea lasiocarpa seed lectin (DLL) was structurally characterized. The lectin presented a high degree of similarity with other lectins isolated from legumes, presenting a jelly roll motif and a metal-binding site stabilizing the carbohydrate-recognition domain. DLL demonstrated differential interactions with carbohydrates, depending on type of glycosidic linkage present in ligands. As observed by the reduction of cell viability in C6 cells, DLL showed strong antiglioma activity by mechanisms involving activation of caspase 3

    NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

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    Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data

    Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

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    International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora
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