Abstract Roadkill is one of the most direct impacts on fauna, leading to numerous direct and indirect impacts. Road-killed animals could serve as a resource for research and teaching purposes, but ...first, they need to have their tissues preserved by some technique. Plastination is one of the most modern techniques for the conservation of biological tissues, its principle is the replacement of body fluids by a curable polymer, resulting in a non-toxic, odorless, and manipulable material. So the main aim of this work was to compose a collection of plastinated roadkill victims from the Biological Reserve Sooretama region, adapting the standard protocol to the different taxa worked here (Avialae, Reptilia, Amphibia, and Mammalia). For this, 42 animals were used, previously frozen and stored in the Sooretama Biological Reserve and Vale Natural Reserve until they were sent for processing. Upon arriving at the Plastination laboratory at the Federal University of Espírito Santo, the animals underwent the 4 stages of plastination: fixation, dehydration, forced impregnation, and chemical cure; some adaptations were made to improve the final specimens. The results proved that the plastination of these animals is extremely viable in generating satisfactory results. Given the results obtained, it becomes clear how plastination can become an alternative to implement in the composition of biological collections using roadkill animals. The animals prepared in this work comprise an unprecedented collection available for different applications, such as exhibitions, practical classes, and research.
Testosterone is associated with an increased risk of coronary heart disease. This study evaluated cardiac remodeling 60 days after myocardial infarction (MI) in rats with testosterone deficiency. One ...week after castration, the animals underwent myocardial infarction. Rats were divided into four groups: orchidectomized (OCT); orchidectomized and infarcted (OCT+MI), MI and control (Sham). The myocyte cross-sectional area and the papillary muscle contractility were evaluated 8 weeks after MI. The coronary bed was perfused with Biodur E20 resin to evaluate the neovascularization after MI. Data were expressed as mean ± SEM followed by ANOVA. Castration reduced myocyte hypertrophy when compared to Sham and myocardial infarction alone as well as preserved the contraction force and activation time after myocardial infarction. After beta-adrenergic stimulation, activation and relaxation kinetics were less impaired in the OCT+MI group than in the MI group. Contraction force was preserved in the OCT+MI group after beta-adrenergic stimulation. Multiple scanning electronic microscope images were obtained to characterize changes in the coronary arteries. Capillary density index was increased in the MI and OCT+MI groups compared with control. The MI and OCT+MI groups were characterized by irregular vessel arrangements with distorted shape, abrupt changes in vessel direction, as well as abrupt changes in diameter after bifurcations when compared to Sham and OCT. The results indicated that testosterone deficiency attenuates adverse cardiac remodeling after MI. Novel findings in this study were that testosterone deficiency in rats, induced by castration, changes the later remodeling after MI, when compared with non castrated rats. The absence of this androgenous hormone seems to be benefic against pathological hypertrophy.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The cell biology discipline constitutes a highly dynamic field whose concepts take a long time to be incorporated into the educational system, especially in developing countries. Amongst the main ...obstacles to the introduction of new cell biology concepts to students is their general lack of identification with most teaching methods. The introduction of elaborated figures, movies and animations to textbooks has given a tremendous contribution to the learning process and the search for novel teaching methods has been a central goal in cell biology education. Some specialized tools, however, are usually only available in advanced research centers or in institutions that are traditionally involved with the development of novel teaching/learning processes, and are far from becoming reality in the majority of life sciences schools. When combined with the known declining interest in science among young people, a critical scenario may result. This is especially important in the field of electron microscopy and associated techniques, methods that have greatly contributed to the current knowledge on the structure and function of different cell biology models but are rarely made accessible to most students. In this work, we propose a strategy to increase the engagement of students into the world of cell and structural biology by combining 3D electron microscopy techniques and 3D prototyping technology (3D printing) to generate 3D physical models that accurately and realistically reproduce a close-to-the native structure of the cell and serve as a tool for students and teachers outside the main centers. We introduce three strategies for 3D imaging, modeling and prototyping of cells and propose the establishment of a virtual platform where different digital models can be deposited by EM groups and subsequently downloaded and printed in different schools, universities, research centers and museums, thereby modernizing teaching of cell biology and increasing the accessibility to modern approaches in basic science.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Highways limit the movement and dispersion of wild animals and contribute to their loss due to roadkills, leading to the isolation and decline of populations, increasing the risk of local extinction. ...The Lowland Tapir Tapirus terrestris is the largest neotropical herbivore-frugivore, and despite its wide distribution in South America it is threatened with extinction. In this study we report six roadkill events of tapirs between 2014 and 2019 in a section of a federal highway crossing the mosaic of Atlantic Forest reserves called Sooretama, one of the last tapir refuges in southeastern Brazil. The traffic in this area is heavy with inadequate speed control, while exotic fruit trees growing along the highway attract wild animals. Water drainage tunnels serve as passageways for some species, including tapirs. However, the tunnels located under the highway are not continuously maintained, reducing its effectiveness. The loss of at least one tapir per year can have serious long-term consequences for one of the last viable lowland tapir populations in the entire Atlantic Forest. Emergency measures are required to avoid vehicle-tapir collisions.
•Adversity exposure in early life contributes to the development of eating disorder.•Neonatal stress increases anxiogenic-like behavior, but only in male rats.•Maternal deprivation induces decreased ...hypothalamic POMC levels in adult males.•Early life adversities affect serotonergic activity in the hypothalamus and amygdala.•Effects of neonatal stress are sexually dimorphic.
Early life experiences have strong influences on brain programming and can affect eating behavior control and body weight later in life. However, there is no consensus about the relationship between neonatal stress and feeding behavior. We evaluated whether maternal deprivation (MD) and maternal separation (MS) alter body weight and appetite using standard rat chow consumption and palatable food. Also, we evaluated anxiety and the expression of the leptin receptor, neuropeptides POMC, CART, NPY in the hypothalamus, as well as the serotoninergic system in the amygdala and hypothalamus as possible modulators of these behaviors. We found a decrease in standard rat chow consumption in MD. However, both neonatal stress protocols increased the consumption of palatable food and led to anxiogenic behavior in male animals. MD led to decreased hypothalamic POMC levels in adult males. Serotonin in the hypothalamus was decreased by both stress models in males and females. In the amygdala, MS decreased serotonin levels while MD increased its metabolite levels. We observed that males are more vulnerable and females are more resilient to the effects of neonatal stress on anxiety-like behavior, as well as on food consumption and on the central changes observed. These data together add support to the concept that the early environment contributes to the development of eating disorders later in life.
Early life adversity has been linked with a higher probability of developing behavioral impairments and environmental manipulation is a strategy that may reduce the negative effects of exposure to ...adversity in early life. Here, we focused on exploring the influence of environmental enrichment (EE) as a protective factor in the context of early life adversity. We hypothesized that 24 hours of maternal deprivation (MD), in the second week of life, could induce anxiety-like behavior alterations and that exposure to EE could induce resilience to these behaviors due to alterations in the serotonergic system. Male Wistar rats were exposed to MD, on postnatal days 11 and 13, and to EE, after weaning. In adulthood, we performed a series of behavioral tests for fear, anxiety, and locomotor activity. We also measured the levels of serotonin in the amygdala and dorsal raphe nucleus. Our results revealed that MD does not impact fear behavior or the levels of serotonin, while EE decreases locomotor activity in a novel environment and enhances exploration in the predator odor test. EE also decreases serotonin in the amygdala and increases its turnover rate levels. Our findings provide insights into the critical timeframe during which stress exposure impacts the development and confirm that exposure to EE has an independent and protective effect for anxiety-like behaviors later in life.
•Maternal deprivation on postnatal days 11 and 13 showed no impact on fear extinction or anxiety.•Environmental enrichment (EE) reduces locomotion and increases exploration time.•EE influences the amygdala, but not dorsal raphe nucleus serotonergic levels.
Panic attacks present a high comorbidity with agoraphobia, separation anxiety and generalized anxiety disorder. Nevertheless, while panic attacks have been frequently equated to fear, the ...relationship of panic disorder with specific phobias remains uncertain. The combination of experimental models of panic and phobias could but afford valuable information about both the comorbidity and causation of these disorders. As it regards, while the defensive behaviors produced by stimulation of dorsal periaqueductal gray matter (DPAG) resemble a panic attack, resistance to capture (RC) behaviors that ensue the kindling of the amygdala (AMY) are reminiscent of a phobic reaction. Therefore, this study examined the thresholds of DPAG-evoked panic-like behaviors in rats showing RC behaviors. Rats bearing electrodes in the DPAG and right AMY were subjected to either the full- (Kin-F) or sham- (Kin-S) kindling of AMY. RC behaviors were evaluated throughout both kindling procedures. Thresholds of DPAG-evoked defensive behaviors were recorded before and after the kindling. Moreover, performances of Kin-F and Kin-S rats in the elevated plus-maze were compared to those of intact controls. Data showed that Kin-F and Kin-S rats perform similarly in the elevated plus-maze, thereby making AMY-kindled rats unlikely as a model of generalized anxiety disorder. On the other hand, whereas the RC is characterized by a marked facilitation of natural freezing and flight behaviors, DPAG-evoked freezing (immobility and exophthalmus) and flight (galloping) behaviors were unexpectedly attenuated. Data suggest that RC is mediated by circuits distinct from those of DPAG-evoked defensive behaviors. Consequently, panic and phobic attacks may be mediated by different mechanisms as well.
Este artigo tem como objetivo a realização de um mapeamento sistemático de literatura para investigar no cenário literário e científico as contribuições do uso da técnica de plastinação aplicada como ...produto educacional e seu resultado para a alfabetização e cultura científica. Nesse sentido, o percurso metodológico adotado foi o mapeamento sistemático de literatura e como resultado foram obtidos 547 trabalhos, dos quais, após a análise e aplicação dos critérios de inclusão e exclusão, 46 trabalhos foram considerados com contribuições relevantes. Como resultado, a técnica de plastinação para conservação de tecidos biológicos, se mostrou eficiente dentro da cultura científica, seu uso em pesquisas, exposições e salas de aula colabora para sua caracterização como ferramenta educacional significativa.
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