Pervasive gaps in Amazonian ecological research

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

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

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

Caracterização da injúria no córtex motor de ratos em um modelo de exposição crônica ao metilmercúrio (MeHg)

The mercury is an environmental contaminant which poses a great risk to human health. Exposure to this toxic metal occurs mainly through a diet contaminated by methylmercury (MeHg) in low concentrations and over a long period of time. Thus, in this study we propose an assessment of the effects of MeHg on the motor cortex in an animal model of chronic exposure and low dose, similar to dietary exposure in areas of high environmental toxicity of mercury. Adult rats were exposed to MeHg for 60 days with a dose of 0.04 mg/kg/day, while the control group received only the vehicle. After this period, they were subjected to behavioral testing in order to evaluate the motor performance after mercury exposure, and then sacrificed and evaluated for oxidative biochemical parameters (change in the concentration of nitrite - NO Lipid Peroxidation - LPO and Antioxidant Capacity Total) as well as evaluation of total deposits of mercury in the motor cortex and changes in cell density of neurons and astrocytes. Data were tabulated and statistically analyzed by Student's t-test (p <0.05). It was possible to observe total mercury deposits in the motor cortex, and deficits in motor parameters, with a reduction in the overall locomotion, on balance and increase in the number of failure, coupled with a significant increase in the levels of NO and LPO and decreased ability antioxidant full of animals exposed, reducing the population of astrocytes and neurons compared to control animals these findings suggest that exposure of adult animals to MeHg, even at low dose and chronically, causes changes in the motor cortex with damage to their functions.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorO mercúrio é um contaminante ambiental que representa um grande risco para a saúde humana. A exposição à este metal tóxico ocorre principalmente através de uma dieta contaminada por Metilmercúrio (MeHg), em baixas concentrações e por um longo período de tempo. Desta forma, neste estudo propomos uma avaliação dos efeitos do MeHg sobre o córtex motor em um modelo animal de exposição crônica e em baixa dose, semelhantemente a exposição alimentar em áreas de grande toxicidade ambiental por mercúrio. Ratos adultos foram expostos ao MeHg durante 60 dias, com uma dose de 0,04 mg/kg/dia, enquanto o grupo controle recebeu apenas o veículo. Após este período, foram submetidos a ensaios comportamentais com intuito de se avaliar o desempenho motor após exposição mercurial, sendo então sacrificados e avaliados por parâmetros bioquímicos oxidantes (alteração na concentração de Nitritos - NO, Peroxidação Lipídica - LPO e Capacidade Antioxidante Total) assim como avaliação dos depósitos totais de mercúrio no córtex motor e alterações da densidade celular de neurônios e astrócitos. Os dados foram tabulados e avaliados estatisticamente pelo teste t-Student (p<0,05). Foi possível observar depósitos de mercúrio total no córtex motor, além de déficit nos parâmetros motores, com a redução na locomoção total, no equilíbrio e aumento no número de quedas, aliados à um significativo aumento nos níveis de NO e LPO e diminuição da capacidade antioxidante total dos animais expostos, com redução da população de astrócitos e neurônios, quando comparados aos animais controle esses achados sugerem que a exposição de animais adultos ao MeHg, mesmo em baixa dose e cronicamente, promove alterações no córtex motor com danos em suas funções

Expressão gênica e viabilidade de folículos pré-antrais submetidos à vitrificação do córtex ovariano de Sapajus apella (macacas-prego)

Vitrification is a biotech that has been increasingly showing promise in several species, among them domestic ruminants (such as sheep, goats and cows) and in nonhuman primates (NHP) (as cynomologus and rhesus), and consists in reducing ultra-rapid temperature by the presence of high concentrations of cryoprotective agents (PCA's) in liquid nitrogen. Thus the aim of this study was to develop a methodology for cryopreservation by vitrification of preantral follicles (PF's) in Sapajus apella. For this purpose, we used females (n = 9) adult Sapajus apella squad belonging to the National Primate Center (CENP). Samples were taken from the ovarian cortex by laparotomy so as not to destabilize the animals reproducibly. The fragments exposed to 8 different treatments: Ethylene glycol (EG) + 40% Sucrose (Sac) dissolved in 0.5 M TCM-199, added to Selenium (2,5, 5 or 10 ng / ml) or Trolox (25, 50 or 100 mM). Following exposure to cryoprotective agents was analyzed follicular viability before and after vitrification, from the follicular morphology, expression of Hsp70 genes, Erp29, Erp60 SOD1 and through the analysis by Polymerase Chain Reaction (PCR), in addition to performing measurement of oxidative stress thru the TEAC (English Total Equivalent Antioxidant Activity). The analyzes showed that vitrification allowed the maintenance of follicular viability by previous exposure to concentrations of ACP's alevadas, especially when supplemented with 50 mM trolox (which resulted in high follicular survival rates) and increased expression of the antioxidant enzyme SOD1. While in the absence of it was observed an increase in rates of follicles degenerate and vacuolated, and reduced expression of the antioxidant enzyme SOD1 and increased expression of chaperone Erp29.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorA vitrificação é uma biotécnica que tem se mostrando cada vez mais promissora em várias espécies, dentre elas ruminantes domésticos (como ovelhas, cabras e vacas), e em primatas não humanos (PNH) (como o cynomologus e rhesus), e consiste na redução ultra-rápida da temperatura mediante a presença de altas concentrações de agentes crioprotetores (ACP’s) em nitrogenio liquido. Desta forma o objetivo deste estudo foi o desenvolvimento de uma metodologia de criopreservação por vitrificação de Folículos Ovarianos Pré-antrais (FOPA’s) em Sapajus apella. Para tanto, foram utilizadas femêas (n=9) adultas de Sapajus apella pertencentes ao plantel do Centro Nacional de Primatas (CENP). Foram realizadas coletas de córtex de tecido ovariano por meio de laparotomia exploratória de modo a não inviabilizar o animal reprodutivamente. Os fragmentos expostos a 8 tratamentos diferentes: Etilenoglicol (EG) 40% + Sacarose (Sac) 0,5 M dissolvidos em TCM-199 adicionados ou não de Selenio (2,5, 5 ou 10 ng/ml) ou Trolox (25, 50 ou 100 mM). Após a exposição aos agentes crioprotetores foi analisada a viabilidade folicular antes e após a vitrificação, a partir da morfologia folicular, expressão dos genes Hsp70, Erp29, Erp60 e Sod1 através da análise por Reação em Cadeia da Polimerase (PCR), além de realizar a dosagem de estresse oxidativo atravéz da TEAC (do inglês Total Equivalent Antioxidant Activity). As análises mostraram que a vitrificação permitiu a manutenção da viabilidade folícular mediante a exposição previa a elevadas concentrações de ACP’s, principalmente quando suplementados com trolox a 50 μM (que resultou em elevadas taxas de sobrevivência folicular) e aumento na expressão da enzima antioxidante Sod1. Enquanto na ausência do mesmo foi observado o aumento nas taxas de folículos degenerados e com vacuolização citoplasmática, além da redução na expressão da enzima antioxidante Sod1 e elevação da expressão da chaperona Erp29

Ovarian Transplantation: Highlight to Non-Human Primates Reproduction

Background: Ovarian transplantation in nonhuman primates (NHP) has been used as a strategy for the development of experimental models for biomedical research in the reproductive area. The prospects for application of this technique range from the restoration of female fertility to the conservation of endangered wild animals. However, studies with NHP were performed mostly focusing on the ovarian transplantation of cryopreserved tissue, in order to simulate the reality of human species, as well as aiming to obtain experimental models suitable for comparative studies. On the other hand, ovarian transplantation could be applied also in NHP species preservation. Review: According to the last census (2012-2014) of the International Union for Conservation of Nature (IUCN), currently, more than half of the 633 types of primates known around the world are in danger of disappearing forever due to the continued destruction of their natural habitat by human activities. Thus, there is an interest to expose the possible methods of ovarian preservation followed by transplantation that can be employed to promote the conservation of endangered NHP. Despite the positive results obtained with avascular autograft of fresh ovarian tissue in NHP, it is important to bring in mind the significant loss of follicles as a result of this procedure due to ischemia and reperfusion during the first days after grafting. This phenomenon leads to the production of reactive oxygen species (ROS) such as hydrogen peroxide, superoxide anion and hydroxyl radical, which are responsible by lipid peroxidation, cell membrane damage and subsequent follicular atresia. An alternative to counteract this oxidative stress consists in the application/administration of different sources of antioxidants previously or during grafting, in the grafted tissue or in the animal receiving the transplant. The most used compounds with a claimed radical scavenger activity are catalase, trolox and some vitamins. In some cases, antioxidants are combined with angiogenic factors, e.g. vascular endothelial growth factor (VEGF) to stimulate revascularization. Another option to avoid the damage caused by ischemia is the whole ovarian transplantation with vascular anastomosis. Therefore, a greater proportion of the pool of follicles survives the procedure and the complete ovary is grafted and not only tissue fragments. However, the vascular microsurgical procedure is complex and, when it is associated with cryopreservation the risks of follicular loss and tissue damage due to improper perfusion are larger. In this context, the aim of this review is to cover important concepts about ovarian transplantation and its current situation in NHP, showing its importance and its advances to reproduction, especially to preserve those endangered ones. Conclusion: Despite advances in tissue response to various applications of the ovarian tissue transplantation reported in this review, it is clear that this technique has been used with paucity as a tool for the conservation of species of PNH endangered. The need for optimization of transplantation techniques, so as to reduce the loss of the follicles during the grafting processes and revascularization, determining the ideal location for the graft, the graft longevity and where in the amount of ovarian tissue required to preserve fertility still are points to be clarified. In this sense, research is ongoing and the perspectives are positive not only to use NHP as a model for human, but also for those endangered species

Effects of chronic ethanol (EtOH) administration (6.5 g/kg/day) during adolescence over a period of 55 days (i.e., from the 35th day until the 90th day of life) in the body weight gain of rats.

<p>The results are expressed as mean ± SEM of the body weight with interval of 7 days (n = 10 animals per group). *P<0.05 compared to control group (One-way ANOVA with repeated measures followed by Tukey’s test).</p

Schematic representation of the methodology utilized to count cells in the motor cortex area.

<p>Schematic representation of the methodology utilized to count cells in the motor cortex area.</p