42 research outputs found

    Faillure in the effect of the analogue (hCG) of luteinizing hormone on the luteal angiogenesis in rats (Rattus novergicus)

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    A compreensão dos mecanismos de controle da atividade ovariana é necessária para o sucesso das biotecnologias da reprodução. Embora existam inúmeros trabalhos a respeito da aplicação do hormônio luteinizante (LH) na função ovariana, pouco se sabe sobre a sua influência na morfologia e formação da vasculatura do corpo lúteo (CL). Diante disto, o presente projeto teve como objetivo a quantificação da densidade vascular dos CLs de animais tratados com Gonadotrofina Corionica Humana (hCG) após a ovulação. Para tanto, foram utilizados ratas wistar, cujos CLs foram divididos em dois grupos: (A) tratado com hCG na manhã seguinte a cópula e (B) controle (solução fisiológica a 0,9 % de NaCl). Foram confeccionadas lâminas dos ovários dos animais para a quantificação da densidade vascular. Os resultados obtidos não revelaram diferenças significantes entre a densidade vascular dos grupos tratado e controle.The knowledge of the mechanisms that affect the control of the ovarian activity is essential for the success of reproduction biotechnologies. Although a number of studies have been carried out in which the luteinizing hormone (LH) was used to control the ovarian activity, little is known about its influence in the morphology and vascular formation of the corpus luteum, aiming to increase the local blood flow. Thus, the objective of the present experiment was the quantification of the vascular density of corpora lutea (Cls) in animals treated with human chorionic gonadotropin (hCG) just after ovulation. Therefore, eighteen wistar rats were used in this experiment. Eight rats in the treated group and ten rats in the control group. Corpora lutea were divided into two groups: group (A) treated with hCG in the following morning after copulation, and group (B) control animals which received an injection of 0.9% sodium chloride solution. Ovaries from each group were used for preparation of histological sections for vascular density qualification. No statistical significance was found between the two groups tested

    Núcleo de pesquisa em suínos como centro formador de recursos humanos para a suinocultura do futuro

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    A suinocultura se destaca dentre as demais atividades produtivas pelo uso massivo de ferramentas tecnológicas, objetivando produzir em maior volume, de forma mais eficiente e sustentável. Nessa conjuntura, a suinocultura brasileira ocupa lugar destacado entre os principais países produtores, ocupando o quarto posto no ranking de produção e exportação de carne suína; dessa forma, fica clara a importância da atividade suinícola como grande geradora de divisas para o país. Assim, faz-se imprescindível a formação de recursos humanos altamente capacitados para que possam militar nesta seara com assertividade, impulsionando cada vez mais a produção de suínos e, em consequência, o desenvolvimento do país. Tendo em vista tal demanda, surgiu o Núcleo de Pesquisa em Suínos, resultado da união de forças entre o Laboratório de Pesquisa em Suínos, o Laboratório de Andrologia e Tecnologia de Embriões Suínos e o Laboratório de Sanidade Suína e Virologia, com o intuito de que os alunos da graduação, e não somente os da pós-graduação, como antes ocorria, pudessem entrar em contato com um cenário fidedigno da produção de suínos. Hoje, os alunos que estão ainda na graduação podem participar de atividades similares àquelas que são realizadas em uma granja comercial de suínos, com a vantagem de estarem sempre monitorados por professores e alunos de pós-graduação.Pig production has gained worldwide notoriety for using cutting-edge technologies aiming not only to increase its productivity and profitability but also to lessen the impact it causes on the environment. In this scenario, Brazil also plays a lead role in global pig production, occupying the forth position in the world ranking of pork production and also of pork exporting, hence, the importance of the pork industry becomes very clear since it is major source of wealth to Brazil’s economy, creating thousands of direct and indirect jobs which contribute to socioeconomic development. Thus, it becomes vital to form highly skilled human resources capable of working in an assertive manner on this field, advancing even more the pork industry and, consequently, the development of the country. To attend this demand, the Swine Research Center was created as a result of the merging of three laboratories (Laboratório de Pesquisa em Suínos; Laboratório de Andrologia e Tecnologia de Embriões Suínos; Laboratório de Sanidade Suína e Virologia), with the main objective of permitting that the undergraduate students could have a hands-on experience on the pig production field. Nowadays, undergraduate students can take part on various activities similar to those of a commercial pig farm, always monitored by faculty and post graduate students

    Sistema carcerário feminino no Brasil e segurança alimentar e nutricional, uma revisão sistemática / Feminine prison system in Brazil and food and nutritional security, a systematic review

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    As leis nacionais reconhecem que a pessoa privada de liberdade deve ter por direito a garantia dos serviços de saúde, onde a alimentação esteja presente em quantidades suficientes e nutricionalmente adequada. Este artigo buscou realizar uma revisão sistemática sobre o sistema carcerário feminino no Brasil e os aspectos relacionados à segurança alimentar e nutricional desta população. A revisão sistemática busca a identificação dos estudos sobre a Segurança Alimentar e Nutricional de mulheres privadas de liberdade em presídios e penitenciárias brasileiras na base de dados SciELO, Lilacs e Google Acadêmico, publicados na língua portuguesa e inglesa, entre os anos de 2010 e 2020. Foram selecionados 4 artigos para serem lidos na íntegra com a utilização de descritores em português e 1 com descritores em inglês, além de 2 teses. Apenas um artigo garantiu a Segurança Alimentar e Nutricional das mulheres privadas de liberdade, onde os demais, apresentaram uma grande vulnerabilidade no cumprimento dos direitos humanos e uma alta prevalência de mulheres com sobrepeso e obesidade.

    Altrenogest during early pregnancy modulates uterine glandular epithelium and endometrial growth factor expression at the time implantation in pigs

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    This study evaluated the effects of supplying altrenogest from day 6-12 of pregnancy on the endometrial glandular epithelium, corpora lutea (CL) morphology, and endometrial and CL gene expression. A total of 12 crossbred females (Landrace × Large White) were used. The females were assigned to 4 treatments according to a random design with a 2 × 2 factorial arrangement, with two categories (sow or gilt) and two treatments (non-treated and treated with altrenogest). On day 6 of pregnancy, animals were allocated to one of the following groups: non-treated (NT, n = 6; 3 sows and 3 gilts), and (T, n = 6; 3 sows and 3 gilts) treated daily with 20 mg of altrenogest, from day 6-12 of pregnancy. All animals were euthanized on day 13 of pregnancy. All CLs were individually weighed, and their volume were determined. The endometrial glandular density (GD), mean glandular area (MGA), and vascular density (VD) were determined by histomorphometric and immunohistochemical analyses. Endometrium samples were collected and analyzed by qRT-PCR to evaluate the abundance of transcripts for VEGF and IGF-I. Females in the T group had higher MGA (P < 0.05) compared to the NT group. There was no effect of treatment on GD or VD for both experimental groups. Sows in the T group had augmented expression of IGF-I (P < 0.05). Progestagen had no detrimental effect on CL morphology. In conclusion, altrenogest improves the uterine environment during the peri-implantation period in pigs without compromising corpora lutea development

    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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    Consistent patterns of common species across tropical tree communities

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    Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

    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

    More than 10,000 pre-Columbian earthworks are still hidden throughout Amazonia

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    Indigenous societies are known to have occupied the Amazon basin for more than 12,000 years, but the scale of their influence on Amazonian forests remains uncertain. We report the discovery, using LIDAR (light detection and ranging) information from across the basin, of 24 previously undetected pre-Columbian earthworks beneath the forest canopy. Modeled distribution and abundance of large-scale archaeological sites across Amazonia suggest that between 10,272 and 23,648 sites remain to be discovered and that most will be found in the southwest. We also identified 53 domesticated tree species significantly associated with earthwork occurrence probability, likely suggesting past management practices. Closed-canopy forests across Amazonia are likely to contain thousands of undiscovered archaeological sites around which pre-Columbian societies actively modified forests, a discovery that opens opportunities for better understanding the magnitude of ancient human influence on Amazonia and its current state

    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
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