320 research outputs found

    ALTERAÇÕES NA MORFOLOGIA ESPERMÁTICA EM TOUROS DE CORTE COM E SEM SUPLEMENTAÇÃO DE ZINCO NA MISTURA MINERAL

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    rebanho sem Zn na suplementação mineral (ZN-0, n=4, 0mg/Zn/kg/dia) foram comparadas com as de touros contemporâneos criados com suplementação adequada (ZN-60FI, n=4, 60mg/Zn/kg/dia). O sêmen foi colhido quinzenalmente, entre 17 e 29 meses de idade. Incluíram-se no exame a análise da cromatina espermática e o perfil morfométrico da cabeça espermática, com base no comprimento, largura superior e inferior (µm) e área (µm2). Os touros do ZN-0 apresentaram redução de espermatozoides normais em relação ao ZN-60FI (62,4 ±2,88% x 74,5 ±2,83), sendo que a prevalência de anormalidades de cromatina (16,7 ±2,05%) e de defeitos de peça intermediária (9,3 ±0,81%) foi superior aos do ZN-60FI (9,5 ±2,03 e 3,2 ±0,80, respectivamente). A microscopia eletrônica de transmissão mostrou irregularidades mitocondriais e ruptura dos feixes de fibras densas externas.  Nos touros do ZN-60FI, a área da cabeça espermática foi proporcionalmente inferior a do ZN-0. Conclui-se que touros criados e mantidos a campo, provenientes de rebanhos com deficiência na suplementação de Zn, estão sujeitos à redução da qualidade seminal, por apresentarem maior frequência de anormalidades morfológicas, na cromatina, e nos padrões morfométricos da cabeça espermática com predomínio de lesões na estrutura mitocondrial e nos feixes de fibras densas na peça intermediária. PALAVRAS-CHAVES: Bovino, cromatina, morfometria espermática, nutrição, qualidade seminal, zinco

    Estudo Retrospectivo do perfil epidemiológico das lesões autoprovocadas no estado do Piauí entre 2018 a 2020 / Retrospective study of the epidemiological profile of self-harm in the state of Piauí between 2018 and 2020

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    Objetivou-se: conhecer o perfil epidemiológico das vítimas de lesão autoprovocada no estado do Piauí entre 2018 e 2020 e verificar se houve aumento ou diminuição dos casos notificados no período inicial da pandemia do COVID-19. Para tal, realizou-se um estudo descritivo, com coleta de dados retrospectiva, por meio do BO epidemiológico 001/2020, disponibilizado pela secretaria de saúde do estado do Piauí (SESAPI). Durante o período de 2018, 2019 e 2020, houve um montante de 3.757 registros de violência autoprovocada, no tracejo do perfil, houve destaque para o biotipo feminino, com idade variando de 15 a 29 anos, principalmente, a raça/cor mais afetada na pratica foi a cor parda, situação conjugal: solteiro, escolaridade: ensino fundamental incompleto, como principal meio usado: envenenamento/intoxicação e como local: residência. Apesar de os dados do ano de 2020 serem somente ate a metade do ano, verifica-se um aumento acentuado dos registros, principalmente se observados os mesmos períodos nos anos de 2018 e 2019. 

    Neuroprotection by adenosine in the brain: From A1 receptor activation to A2A receptor blockade

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    Adenosine is a neuromodulator that operates via the most abundant inhibitory adenosine A1 receptors (A1Rs) and the less abundant, but widespread, facilitatory A2ARs. It is commonly assumed that A1Rs play a key role in neuroprotection since they decrease glutamate release and hyperpolarize neurons. In fact, A1R activation at the onset of neuronal injury attenuates brain damage, whereas its blockade exacerbates damage in adult animals. However, there is a down-regulation of central A1Rs in chronic noxious situations. In contrast, A2ARs are up-regulated in noxious brain conditions and their blockade confers robust brain neuroprotection in adult animals. The brain neuroprotective effect of A2AR antagonists is maintained in chronic noxious brain conditions without observable peripheral effects, thus justifying the interest of A2AR antagonists as novel protective agents in neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease, ischemic brain damage and epilepsy. The greater interest of A2AR blockade compared to A1R activation does not mean that A1R activation is irrelevant for a neuroprotective strategy. In fact, it is proposed that coupling A2AR antagonists with strategies aimed at bursting the levels of extracellular adenosine (by inhibiting adenosine kinase) to activate A1Rs might constitute the more robust brain neuroprotective strategy based on the adenosine neuromodulatory system. This strategy should be useful in adult animals and especially in the elderly (where brain pathologies are prevalent) but is not valid for fetus or newborns where the impact of adenosine receptors on brain damage is different

    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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    2 nd Brazilian Consensus on Chagas Disease, 2015

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    Abstract Chagas disease is a neglected chronic condition with a high burden of morbidity and mortality. It has considerable psychological, social, and economic impacts. The disease represents a significant public health issue in Brazil, with different regional patterns. This document presents the evidence that resulted in the Brazilian Consensus on Chagas Disease. The objective was to review and standardize strategies for diagnosis, treatment, prevention, and control of Chagas disease in the country, based on the available scientific evidence. The consensus is based on the articulation and strategic contribution of renowned Brazilian experts with knowledge and experience on various aspects of the disease. It is the result of a close collaboration between the Brazilian Society of Tropical Medicine and the Ministry of Health. It is hoped that this document will strengthen the development of integrated actions against Chagas disease in the country, focusing on epidemiology, management, comprehensive care (including families and communities), communication, information, education, and research

    The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

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    AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

    Observation of the decay Λ <sub>b</sub> <sup>0</sup>  → ψ(2S)pπ<sup>−</sup>

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    International audienceThe Cabibbo-suppressed decay Λb0_{b}^{0}  → ψ(2S)pπ^{−} is observed for the first time using a data sample collected by the LHCb experiment in proton-proton collisions corresponding to 1.0, 2.0 and 1.9 fb1^{−1} of integrated luminosity at centre-of-mass energies of 7, 8 and 13 TeV, respectively. The ψ(2S) mesons are reconstructed in the μ+^{+}μ^{−} final state. The branching fraction with respect to that of the Λb0_{b}^{0}  → ψ(2S)pK^{−} decay mode is measured to b

    Evidence for an nc(1S)ff- resonance in B0 yc(1S)K+ decays

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    A Dalitz plot analysis of B0→ηc(1S)K+π- decays is performed using data samples of pp collisions collected with the LHCb detector at centre-of-mass energies of s=7,8 and 13TeV , corresponding to a total integrated luminosity of 4.7fb-1 . A satisfactory description of the data is obtained when including a contribution representing an exotic ηc(1S)π- resonant state. The significance of this exotic resonance is more than three standard deviations, while its mass and width are 4096±20-22+18MeV and 152±58-35+60MeV , respectively. The spin-parity assignments JP=0+ and JP=1- are both consistent with the data. In addition, the first measurement of the B0→ηc(1S)K+π- branching fraction is performed and gives B(B0→ηc(1S)K+π-)=(5.73±0.24±0.13±0.66)×10-4, where the first uncertainty is statistical, the second systematic, and the third is due to limited knowledge of external branching fractions

    Trajetórias da Educomunicação nas Políticas Públicas e a Formação de seus Profissionais

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    Esta obra é composta com os trabalhos apresentados no primeiro subtema, TRAJETÓRIA – Educação para a Comunicação como Política pública, nas perspectivas da Educomunicação e da Mídia-Educação, do II Congresso Internacional de Comunicação e Educação. Os artigos pretendem propiciar trocas de informações e produzir reflexões com os leitores sobre os caminhos percorridos, e ainda a percorrer, tendo como meta a expansão e a legitimação das práticas educomunicativas e/ou mídia-educativas como política pública para o atendimento à formação de crianças, adolescentes, jovens e adultos, no Brasil e no mundo
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