24 research outputs found

    Carcass characteristics and meat evaluation of Nelore cattle subjected to different antioxidant treatments

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    Forty Nelore cattle were used to evaluate the effects of supplementation with different antioxidants on carcass characteristics and meat quality of feedlot cattle. Animals were fed Brachiaria brizantha hay and subjected to five treatments (control and four antioxidants: zinc, selenium, vitamin E, and selenium + vitamin E). After a 105-day feeding period, cattle were slaughtered. Tissue composition, as well as carcass proximate composition, color, tenderness, pH, and fatty acid profile were evaluated. Analysis of variance was carried out and means compared by Tukey test at 0.05 probability. The group fed selenium showed the lowest muscle amount (66.61 g/100 g) compared with the other antioxidants evaluated. There was no difference among treatments for bone, fat, and comestible portion percentages as well as muscle:bone, muscle:fat, and comestible portion:bone ratios, with mean values of 16.85 g/100 g, 14.70 g/100 g, 82.99 g/100 g, 4.06, 4.85, and 4.95, respectively. Neither brightness, red, or yellow contents of the meat nor carcass pH were affected by treatments. For tenderness and losses during thawing and cooking, there were no differences among treatments, with averages of 6.43 kgf cm2, 3.22 g/100 g, and 21.15 g/100 g, respectively. Supplementation of Nelore cattle fed Brachiaria brizantha hay with antioxidants do not influence carcass characteristics or meat quality. However, vitamin E supplementation reduces the levels of omega 3 fatty acid, whereas supplementation with selenium + vitamin E promotes an increase in linoleic and palmitoleic acids and a decrease in myristoleic acid, making the supplementation feasible due to the beneficial effects provided by these acids

    Fontes alternativas de potássio em cafeeiros para melhoria da fertilidade do solo, da produtividade e da qualidade de bebida

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    The objective of this work was to evaluate alternative sources of potassium for improving soil fertility and coffee productivity and beverage quality. The experiment was conducted in a coffee (Coffea arabica) crop, planted in an Oxisol area, in the municipality of Patrocínio, in the state of Minas Gerais, Brazil. The treatments consisted of the K sources TK47 and Super Greensand (SG) – both based on glauconite silicate mineral –, at the following doses: 0 kg ha-1 K2O (control); 42, 84, 168, and 336 kg ha-1 K2O from TK47; 618 kg ha-1 K2O from KCl; and 168 kg ha-1 K2O from SG. A randomized complete block design was used, with four replicates in each treatment. The experimental units consisted of three rows with ten plants each, using the eight central plants as the useful plot. Potassium fertilization with TK47 increased soil fertility, correcting soil acidity and elevating K+, P, and Ca2+ contents, effective cation exchange capacity, and Zn2+ and Fe2+ levels in the soil. Fertilization with 336 kg ha-1 K2O from TK47, in a single dose, provides grain yield and polyphenol oxidase activity similar to those of fertilization with 618 kg ha-1 K2O from KCl, in a split-dose, but a better sensory analysis of the resultant beverage.O objetivo deste trabalho foi avaliar fontes alternativas de potássio para melhoria da fertilidade do solo e da produtividade e da qualidade de bebida do cafeeiro. O experimento foi conduzido em lavoura de café (Coffea arabica) plantada em área de Latossolo, no Município de Patrocínio, no Estado de Minas Gerais. Os tratamentos consistiram da aplicação das fontes de K TK47 e Super Greensand (SG) – ambas baseadas no mineral silicatado glauconita –, nas seguintes doses: 0 kg ha-1 de K2O (controle); 42, 84, 168 e 336 kg ha-1 de K2O de TK47; 618 kg ha-1 de K2O de KCl; e 168 kg ha-1 de K2O de SG. Utilizou-se o delineamento de blocos ao acaso, com quatro repetições por tratamento. As unidades experimentais foram constituídas por três linhas de dez plantas cada uma, tendo-se considerado as oito plantas centrais como parcela útil. A adubação potássica com TK47 aumentou a fertilidade do solo, com correção da acidez e com elevação dos teores de K+, P, Ca2+, da capacidade de troca de cátions efetiva, e dos níveis de Zn2+ e Fe2+ no solo. A adubação com 336 kg ha-1 de K2O de TK47, em dose única, proporciona produção de grãos e atividade de polifenoloxidase semelhantes às da fertilização com 618 kg ha-1 de K2O de KCl, de forma parcelada, mas melhor análise sensorial da bebida resultante

    Synthesis and biological evaluation of novel imidazolidine derivatives as candidates to schistosomicidal agents

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    Introduction: Schistosomiasis is an infectious parasitic disease caused by trematodes of the genus Schistosoma, which threatens at least 258 million people worldwide and its control is dependent on a single drug, praziquantel. The aim of this study was to evaluate the anti-Schistosoma mansoni activity in vitro of novel imidazolidine derivatives. Material and methods: We synthesized two novel imidazolidine derivatives: (LPSF/PTS10) (Z)-1-(2-chloro-6-fluorobenzyl)-4-(4-dimethylaminobenzylidene)-5-thioxoimidazolidin-2-one and (LPSF/PTS23) (Z)-1-(2-chloro-6-fluoro-benzyl)-5-thioxo-4-(2,4,6-trimethoxy-benzylidene)-imidazolidin-2-one. The structures of two compounds were determined by spectroscopic methods. During the biological assays, parameters such as motility, oviposition, mortality and analysis by Scanning Electron Microscopy were performed. Results: LPSF/PTS10 and LPSF/PTS23 were considered to be active in the separation of coupled pairs, mortality and to decrease the motor activity. In addition, LPSF/PTS23 induced ultrastructural alterations in worms, after 24 h of contact, causing extensive erosion over the entire body of the worms. Conclusion: The imidazolidine derivatives containing the trimetoxy and benzylidene halogens showed promising in vitro schistosomicidal activity

    Pervasive gaps in Amazonian ecological research

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    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

    Diretriz da Sociedade Brasileira de Cardiologia sobre Diagnóstico e Tratamento de Pacientes com Cardiomiopatia da Doença de Chagas

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    This guideline aimed to update the concepts and formulate the standards of conduct and scientific evidence that support them, regarding the diagnosis and treatment of the Cardiomyopathy of Chagas disease, with special emphasis on the rationality base that supported it.  Chagas disease in the 21st century maintains an epidemiological pattern of endemicity in 21 Latin American countries. Researchers and managers from endemic and non-endemic countries point to the need to adopt comprehensive public health policies to effectively control the interhuman transmission of T. cruzi infection, and to obtain an optimized level of care for already infected individuals, focusing on diagnostic and therapeutic opportunistic opportunities.   Pathogenic and pathophysiological mechanisms of the Cardiomyopathy of Chagas disease were revisited after in-depth updating and the notion that necrosis and fibrosis are stimulated by tissue parasitic persistence and adverse immune reaction, as fundamental mechanisms, assisted by autonomic and microvascular disorders, was well established. Some of them have recently formed potential targets of therapies.  The natural history of the acute and chronic phases was reviewed, with enhancement for oral transmission, indeterminate form and chronic syndromes. Recent meta-analyses of observational studies have estimated the risk of evolution from acute and indeterminate forms and mortality after chronic cardiomyopathy. Therapeutic approaches applicable to individuals with Indeterminate form of Chagas disease were specifically addressed. All methods to detect structural and/or functional alterations with various cardiac imaging techniques were also reviewed, with recommendations for use in various clinical scenarios. Mortality risk stratification based on the Rassi score, with recent studies of its application, was complemented by methods that detect myocardial fibrosis.  The current methodology for etiological diagnosis and the consequent implications of trypanonomic treatment deserved a comprehensive and in-depth approach. Also the treatment of patients at risk or with heart failure, arrhythmias and thromboembolic events, based on pharmacological and complementary resources, received special attention. Additional chapters supported the conducts applicable to several special contexts, including t. cruzi/HIV co-infection, risk during surgeries, in pregnant women, in the reactivation of infection after heart transplantation, and others.     Finally, two chapters of great social significance, addressing the structuring of specialized services to care for individuals with the Cardiomyopathy of Chagas disease, and reviewing the concepts of severe heart disease and its medical-labor implications completed this guideline.Esta diretriz teve como objetivo principal atualizar os conceitos e formular as normas de conduta e evidências científicas que as suportam, quanto ao diagnóstico e tratamento da CDC, com especial ênfase na base de racionalidade que a embasou. A DC no século XXI mantém padrão epidemiológico de endemicidade em 21 países da América Latina. Investigadores e gestores de países endêmicos e não endêmicos indigitam a necessidade de se adotarem políticas abrangentes, de saúde pública, para controle eficaz da transmissão inter-humanos da infecção pelo T. cruzi, e obter-se nível otimizado de atendimento aos indivíduos já infectados, com foco em oportunização diagnóstica e terapêutica. Mecanismos patogênicos e fisiopatológicos da CDC foram revisitados após atualização aprofundada e ficou bem consolidada a noção de que necrose e fibrose sejam estimuladas pela persistência parasitária tissular e reação imune adversa, como mecanismos fundamentais, coadjuvados por distúrbios autonômicos e microvasculares. Alguns deles recentemente constituíram alvos potenciais de terapêuticas. A história natural das fases aguda e crônica foi revista, com realce para a transmissão oral, a forma indeterminada e as síndromes crônicas. Metanálises recentes de estudos observacionais estimaram o risco de evolução a partir das formas aguda e indeterminada e de mortalidade após instalação da cardiomiopatia crônica. Condutas terapêuticas aplicáveis aos indivíduos com a FIDC foram abordadas especificamente. Todos os métodos para detectar alterações estruturais e/ou funcionais com variadas técnicas de imageamento cardíaco também foram revisados, com recomendações de uso nos vários cenários clínicos. Estratificação de risco de mortalidade fundamentada no escore de Rassi, com estudos recentes de sua aplicação, foi complementada por métodos que detectam fibrose miocárdica. A metodologia atual para diagnóstico etiológico e as consequentes implicações do tratamento tripanossomicida mereceram enfoque abrangente e aprofundado. Também o tratamento de pacientes em risco ou com insuficiência cardíaca, arritmias e eventos tromboembólicos, baseado em recursos farmacológicos e complementares, recebeu especial atenção. Capítulos suplementares subsidiaram as condutas aplicáveis a diversos contextos especiais, entre eles o da co-infecção por T. cruzi/HIV, risco durante cirurgias, em grávidas, na reativação da infecção após transplante cardíacos, e outros.    Por fim, dois capítulos de grande significado social, abordando a estruturação de serviços especializados para atendimento aos indivíduos com a CDC, e revisando os conceitos de cardiopatia grave e suas implicações médico-trabalhistas completaram esta diretriz.&nbsp

    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 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

    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

    Characteristics of cattle breed nelore meat fed with braquiaria hay and submitted to different antioxidants

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    Submitted by Jaqueline Silva ([email protected]) on 2016-10-17T16:40:01Z No. of bitstreams: 2 Dissertação - Thiago de Jesus do Carmo - 2014.pdf: 1906807 bytes, checksum: e5d7d3a5e67cae3ea55b63178617ba2e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Approved for entry into archive by Jaqueline Silva ([email protected]) on 2016-10-17T17:12:06Z (GMT) No. of bitstreams: 2 Dissertação - Thiago de Jesus do Carmo - 2014.pdf: 1906807 bytes, checksum: e5d7d3a5e67cae3ea55b63178617ba2e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Made available in DSpace on 2016-10-17T17:12:06Z (GMT). No. of bitstreams: 2 Dissertação - Thiago de Jesus do Carmo - 2014.pdf: 1906807 bytes, checksum: e5d7d3a5e67cae3ea55b63178617ba2e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-04-30Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPqThe pastures in the Brazilian Midwest are mostly formed by grasses of the genus Brachiaria. It is difficult to improve these pastures due to the large quantity of saponins found in these grasslands, causing poisoning in animals leading to a low level of production or even death. Antioxidants optimize animal production and decrease the effects of saponins on the animal, but also, improves meat appearance and increases its shelf life. To evaluate the effects of supplementation with different antioxidants on performance, oxidative stress, as well as quantitative and qualitative aspects of the carcass in feedlot cattle, an experiment was conducted with 40 Nelore cattle fed Brachiaria hay and subjected to five treatments (control and groups with antioxidants: zinc, selenium, vitamin E and selenium + vitamin E). There were eight animals per group, each animal considered a replication. Tissue composition as well as carcass proximate composition, color, tenderness, pH and fatty acid profile were evaluated. In the present experimental conditions, supplementation of cattle fed Brachiaria brizantha hay and supplemented with antioxidants, did not lead to difference for carcass traits and meat quality. However, supplementation with vitamin E reduced Omega 3 levels in this study.As pastagens na região Centro-Oeste são em sua grande maioria formadas por gramíneas do gênero braquiária. O sistema de produção a pasto tem grandes dificuldades de melhorias, o qual apresenta um problema a ser enfrentado, que é a quantidade elevada de saponinas presentes na pastagem, as quais causam intoxicações nos animais levando-os a um baixo nível de produção ou até a sua morte. Os antioxidantes otimizam a produção animal e diminuem os efeitos das saponinas no animal, como também melhora o aspecto da carne e aumenta sua vida útil. Para avaliar os efeitos da suplementação com diferentes antioxidantes sobre o desempenho, estresse oxidativo e aspectos quantitativos e qualitativos de carcaça e da carne de bovinos confinados, foi realizado um experimento com 40 bovinos Nelore, alimentados com feno de braquiária e submetidos a cinco tratamentos (grupos controle e grupos suplementados com antioxidantes: zinco, selênio, vitamina E e selênio + vitamina E), sendo oito animais por grupo, cada animal uma repetição. Para tanto, avaliou-se na carcaça a composição tecidual e na carne a composição centesimal, cor, maciez, pH e perfil de ácidos graxos. Nas condições do presente experimento a suplementação de bovinos alimentados com feno de Brachiaria brizantha e suplementados com os antioxidantes acima citados não promoveu diferença para as características da carcaça e da carne. Porém, observa-se que a suplementação com vitamina E reduziu os valores de Omega 3
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