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The effects of previous social experiences on social behavior have been demonstrated across species both in cooperative and competitive contexts. In dominance-subordinate hierarchies, differences across social ranks have been observed in many different mechanisms. Dominance hierarchies interfere in defensive behavior, where subordinate animals present a greater defensive behavior, regarding potential threats (“anxiety-like behavior”), than dominant animals. The serotonergic system plays a key role in regulating and mediating threat responses, including 5-HT2 receptors in the types of proximal threat responses modulated by the stress of social defeat. We separated 148 adult zebrafish in pairs, and allowed to interact for five days; after that, the dominant-subordinate rank was determined, and animals were treated with a 5-HT2Creceptor agonist (MK-212) or antagonist (RS-102221) before being observed in the novel tank test. While MK-212 increased bottom-dwelling, erratic swimming, and freezing across all statuses, RS-102221 decreased these variables in dominants but increased them in subordinates. Moreover, the effects of MK-212 were larger in subordinates than in controls or dominants, suggesting a sensitization of the 5-HT2Creceptor.

Abstract Serotonin or 5-hydroxytryptamine (5-HT) is a monoaminergic neurotransmitter that is known to influence behaviour in various animal species. Its actions, however, are complex and not well-understood yet. Here, we tested whether and how two 5-HT receptor agonists and a 5-HT receptor antagonist influence behaviour in common waxbills (Estrilda astrild), focusing on aggression, movement and feeding. We applied acute administration of either 8-OH-DPAT (a 5-HT1A receptor agonist), fluoxetine (a selective serotonin reuptake inhibitor; SSRI) or WAY 100,635 (a 5-HT1A receptor antagonist), and then quantified behaviour in the context of competition for food. Waxbills treated with the SSRI fluoxetine showed an overall decrease of aggressive behaviour, activity and feeding, while we found no significant effects of treatment with the other serotonergic enhancer (8-OH-DPAT) or with the antagonist WAY 100,635. Since both 8-OH-DPAT and WAY 100,635 act mainly on 5-HT1A receptor pathways, while fluoxetine more generally affects 5-HT pathways, our results suggest that receptors other than 5-HT1A are important for serotonergic modulation of waxbill behaviour. Significance statement The serotonergic system is of interest for current behavioural research due to its influence on a range of behaviours, including aggression, affiliative behaviour, feeding and locomotion in various species. There are, however, numerous discrepancies regarding the behavioural effects of serotonin across studies. We used acute pharmacological manipulations of the serotonergic system in common waxbills, using two serotonin enhancers (8-OH-DPAT and fluoxetine) and a serotonin blocker (WAY 100,635). Behavioural effects of these pharmacological manipulations on aggressiveness, movement and feeding, during tests of competition over food, indicated an anxiogenic-like effect of fluoxetine, but not of 8-OH-DPAT and WAY 100,635. This suggests a distinct role for different serotonergic pathways on waxbill behaviour.

This paper discusses some of the conceptions about memory found in activity theory - with a special focus on Vygotsky and Zinchenko - and compared them with some of the propositions and conceptions of enactive cognition. An approximation between these two theories, mediated by Marxian conceptions of the "total human being," allows for a more interesting and coherent elaboration of the role of memory in the classroom - overcoming models that understand memory as a mere "warehouse," and its role as that of "memorization" of content. From this approach, we can understand memory as an act of creation rather than reproduction, favoring the unity between subject and object. This also allows us to criticize and overcome education as a process of alienation, and has important practical consequences from the reading of memory as pragmatic.

Social preference tests can be used to analyze variables that influence and modify social behaviors, and to investigate effects of substances such as medications, drugs, and hormones. They may become important tools for finding a valid model to study neuropsychiatric changes and to study human neurodevelopmental processes that have been impaired by social events. While a preference for conspecifics has been shown for different species, social novelty has been used as a model for anxiety-like behavior in rodents. The goal of this research was to understand the roles of stimulus salience (numerousness) and novelty in social investigation and social novelty tests in zebrafish (Danio rerioHamilton 1822). We used a sequential design, in which animals are exposed first to a social investigation test (with dichotomous presentation of novel conspecifics vs. empty tank) and then to a social novelty test (with dichotomous presentation of the already known conspecific and a novel conspecific). In experiment 1, animals were presented to either 1 or 3 (vs. an empty tank) conspecifics as stimuli. In experiment 2, animals were presented to 1 vs. 3 conspecifics as stimuli. In experiment 3, animals were observed in the social investigation and social novelty tests for 3 consecutive days. The results showed equivalence between 1 or 3 conspecifics in the social investigation and social novelty tests, although animals were able to discriminate between different shoal sizes. These preferences do not change with repeated test exposure, suggesting novelty to be a minor contributor to social investigation and social novelty in zebrafish.

Serotonin (5-HT) show important relations to stress, and this relationship is crucial to understanding the psychobiology of common mental disorders. Environmental stressors regulate phasic and tonic serotonin levels, which are related to valence and outcome probabilities. This regulation takes place at smaller timescales, but also at the level of gene expression regulation. Moreover, genes related to the synthesis, metabolism, and transport of 5-HT are also involved in this regulation. Genetic variations in these genes modulate how stressors can lead to mental distress, but stressors also modulate gene expression in a genotype-dependent manner. As a result, the relationship between psychosocial stress and the regulation of the expression of 5-HTergic genes is bidirectional. This suggests a “circular causality” in which gene variations control tonic and phasic 5-HT signals (“upward causality”), while configurations and functions of the entire organism determine which genes are up- or downregulated, or which gene products are actually relevant in each situation (“downward causality”). The highly important role of social factors in human psychopathology is highlighted, and factors such as attachment and socioeconomic status modulate how the circular vertical causality between genes, neurotransmitters, and behavior is organized, representing circular horizontal causality. These complex interrelationships also suggest that more refined epistemologies are needed to fully grasp the relationship between 5-HT and common mental disorders.

Serotonin (5-HT) receptors have been implicated in social behavior in vertebrates. Zebrafish (Danio rerio) have been increasingly being used behavioral neuroscience to study the neurobiological correlates of behavior, including sociality. Nonetheless, the role of 5-HT2C receptors in different social functions were not yet studied in this species. Zebrafish were treated with the agonist MK-212 (2 mg/kg) or the antagonist RS-102221 (2 mg/kg) and tested in the social interaction and social novelty tests, conditional approach test, or mirror-induced aggressive displays. MK-212 increased preference for an unknown conspecific in the social investigation test, but also increased preference for the known conspecific in the social novelty test; RS-102221, on the other hand, decreased preference in the social investigation test but increased preference for the novel conspecific in the social novelty test. MK-212 also decreased predator inspection in the conditional approach test. While RS-102221 decreased time in the display zone in the mirror-induced aggressive display test, it increased display duration. Overall, these results demonstrate the complex role of 5-HT2C receptors in different social contexts in zebrafish, revealing a participation in social plasticity in vertebrates.

Psychopathology has been criticized for decades for its reliance on a brain-centred and over-reductionist approach which views mental disorders as disease-like natural kinds. While criticisms of brain-centred psychopathologies abound, these criticisms sometimes ignore important advances in the neurosciences which view the brain as embodied, embedded, extended and enactive, and as fundamentally plastic. A new onto-epistemology for mental disorders is proposed, focusing on a biocultural model, in which human brains are understood as embodied and embedded in ecosocial niches, and with which individuals enact particular transactions characterized by circular causality. In this approach, neurobiological bases are inseparable from interpersonal and socio-cultural factors. This approach leads to methodological changes in how mental disorders are studied and dealt with.

The dopaminergic system of zebrafish is complex and the numerous pathways and receptors in the central nervous system (CNS) are being extensively studied. A critical factor for the synthesis, activation and release of catecholamines (CAs) is the presence of tyrosine hydroxylase, an enzyme which converts L-tyrosine into levodopa. Levodopa thus is the intermediary in the synthesis of dopamine (DA) and norepinephrine (NE) and promotes its release; therefore, CAs play an important role in the CNS with hormonal functions. Here, we use levodopa/carbidopa to clarify the involvement of the dopaminergic pathway in the stress response in zebrafish submitted to an acute stress challenge. Acute stress was induced by chasing fish with a net for 2 min and assessed by measuring whole-body cortisol levels. Two experiments were carried out, the first with exposure to levodopa/carbidopa and the second with exposure to AMPT and levodopa/carbidopa. Levodopa/carbidopa balances the stress response through its action on the zebrafish hypothalamic–pituitary–adrenal (HPA) axis. Changes in cortisol levels suggest that DA was related to the balance of the stress response and that NE decreased this response. These effects were specific to stress since levodopa/carbidopa did not induce changes in cortisol in non-stressed fish.

The term "Science Anxiety" reflects a negative attitude and aversion toward scientific concepts, scientists, and science-related activities. In Brazil, there are no instruments to assess this construct. We present a translation of the Science Anxiety Questionnaire created by Czerniak and Chiarelott (1984), as well as its content and face validation, reliability, and item evaluation by Rasch analysis. The resulting Science Anxiety Scale features 32 Likert-type items, with good reliability (α = 0.9), and three factors. Rasch analysis suggests that items in factor 1 (which involves testing situations and direct application of scientific concepts and principles in a school context) are easier and have higher mean scores than items in factors 3 (which involves performance in front of other people when performing science-related activities) and 2 (which involves general application of scientific principles in everyday life). The proposed Science Anxiety Scale represents an easily applicable and potentially useful instrument for research on this phenomenon in science education.

SummaryThis study describes the embryonic development of Moenkhausia oligolepis in laboratory conditions. After fertilization, the embryos were collected every 10 min up to 2 h, then every 20 min up to 4 h, and afterwards every 30 min until hatching. The fertilized eggs of M. oligolepis measured approximately 0.85 ± 0.5 mm and had an adhesive surface. Embryonic development lasted 14 h at 25ºC through the zygote, cleavage, blastula, gastrula, neurula, and segmentation phases. Hatching occurred in embryos around the 30-somites stage. The present results contribute only the second description of embryonic development to a species from the Moenkhausia genus, being also the first for this species. Such data are of paramount importance considering the current conflicting state of this genus phylogenetic classification and may help taxonomic studies. Understanding the biology of a species that is easily managed in laboratory conditions and has an ornamental appeal may assist studies in its reproduction to both supply the aquarium market and help the species conservation in nature. Moreover, these data enable the use of M. oligolepis as a model species in biotechnological applications, such as the germ cell transplantation approach.

SummaryThe seminal characteristics of Moenkhausia oligolepis are described. Three males were induced with a single dose of carp pituitary. Semen was collected 6 h after induction, and diluted in dibasic sodium phosphate extender solution. For motility analysis, 1 µl of diluted semen was added to 10 µl of distilled water to achieve gamete activation. The average duration of total motility was 76.67 s; while the average sperm motility rate at intervals of 15 s was 95.3, 85.3, 59.6, 31.7, 13.0, 4.6 and 1.2%. To determine sperm concentration in samples, 0.5 μl of semen was diluted with 500 μl of glutaraldehyde. An aliquot of 10 μl of this dilution was utilized for cell counting. An average count of 4.97 × 109 ± 3.46 sperm/ml was obtained. Morphological analyses were performed using eosin–nigrosine dye; 20.33% of the sperm were observed to be dead. Live sperm, comprising the other 79.67%, had an average length of approximately 30 µm, with a head diameter of 4.488 ± 0.7 µm; and a flagella plus mid-piece length of 26.071 ± 12.4 µm. Of those sperm, 69% had a normal morphology, while 31% had primary and secondary abnormalities. The observed abnormality rate did not have a detrimental effect on artificial fertilization potential for the species. The description of the seminal characteristics of a species is one of the most important sets of information required for artificial reproduction of fish in captivity. It also contributes significantly to the total biological knowledge of the studied species.

Current theories on the role of serotonin (5-HT) in vertebrate defensive behavior suggest that this monoamine increases anxiety but decreases fear, by acting at different levels of the neuroaxis. This paradoxical, dual role of 5-HT suggests that a serotonergic tone inhibits fear responses, while an acute increase in 5-HT would produce anxiety-like behavior. However, so far no evidence for a serotonergic tone has been found. Using zebrafish alarm responses, we investigate the participation of phasic and tonic 5-HT levels in fear-like behavior, as well as in behavior after stimulation. Conspecific alarm substance (CAS) increased bottom-dwelling and erratic swimming, and animals transferred to a novel environment after CAS exposure (post-exposure behavior) showed increased bottom-dwelling and freezing. Clonazepam blocked CAS effects during and after exposure. Acute fluoxetine dose-dependently decreased fear-like behavior, but increased post-exposure freezing. Metergoline had no effect on fear-like behavior, but blocked the effects of CAS on post-exposure behavior; similar effects were observed with para-chlorophenylalanine. Finally, CAS was shown to decrease the activity of monoamine oxidase in the zebrafish brain after exposure. These results suggest that phasic and tonic serotonin encode an aversive expectation value, switching behavior toward cautious exploration/risk assessment/anxiety when the aversive stimulus is no longer present.

O presente estudo analisou a confiabilidade e a estrutura fatorial da Escala de Ansiedade à Matemática (EAM), bem como parâmetros de item avaliados por análise de Rasch. A EAM foi aplicada a estudantes do Ensino Médio de uma escola pública do interior do Pará, através de formulário online. A escala apresentou boa confiabilidade (α = 0,947), e estrutura de dois fatores, identificados preliminarmente como Ansiedade Numérica e Ansiedade à Avaliação Matemática. Os itens do fator Ansiedade à Avaliação Matemática apresentaram maior média e menor dificuldade do que os itens do fator Ansiedade Numérica. Esses resultados sugerem que a EAM é confiável, robusta, e capaz de capturar a estrutura latente do construto Ansiedade à Matemática.

A Ansiedade à Matemática (AM) gera sofrimento emocional, sucessivos fracassos, fuga e evitação em estudantes adolescentes quando expostos à necessidade de aprender a disciplina. A partir de uma perspectiva de cognição social, o presente artigo discute alguns fatores interpessoais, contextuais e institucionais que, sob a forma de pressão, funcionam como gatilhos para o surgimento de AM, os quais, por sua vez, resultam em fracasso escolar. Discutem-se ainda as formas, muitas vezes sutis, de pressão na sala de aula e na escola, bem como em ambientes estendidos, a exemplo da família. Também são apresentados resultados relativos a pontos de corte da Escala de Ansiedade à Matemática e à distribuição de valores em uma amostra de estudantes do Ensino Médio de uma escola pública de Rondon do Pará, sudeste do Pará. A aplicação de critérios de corte com base em quartis da amostra é consistente com achados anteriores da literatura e pode permitir entender a relação entre AM, pressões interpessoais, contextuais e institucionais, e fracasso escolar. Observaram-se ainda maiores escores globais em meninas do que em meninos, o que pode estar relacionado a expectativas sociais e culturais sobre gênero e desempenho matemático. Sugerimos que olhar para aspectos culturais e sociais pode ajudar a compreender o fenômeno da AM e interferir sobre ele. Math Anxiety: Attitudes and social pressure Abstract Math Anxiety (MA) generates emotional distress, successive failures, avoidance, and evasion in adolescent students when exposed to the need to learn mathematics. From the viewpoint of social cognition, the present article discusses interpersonal, contextual, and institutional factors that, in the form of pressure, act as triggers for the emergence of MA, which, in turn, result in school failure. The often subtle forms of pressure in the classroom and school, as well as in extended settings, such as the family, are also discussed. Results are also presented regarding the validation of the Math Anxiety Scale and their distribution in a sample of high school students from a public school in Rondon do Pará, southeastern Pará, Brazil. The application of cut-off criteria based on sample quartiles is consistent with previous findings in the literature, and may allow understanding the relationship between MA, interpersonal, contextual, and institutional pressures, as well as school failure. Higher overall scores were also observed in girls than in boys, which may be related to social and cultural expectations about gender and math performance. We suggest that looking at cultural and social aspects may help to understand the phenomenon of MA and interfere with it.

Resumo O trabalho pedagógico remoto emergencial foi implementado em muitas escolas do Brasil durante a pandemia da Covid-19, como forma de diminuir os contatos entre indivíduos e, consequentemente, diminuir a taxa de transmissão da doença, mantendo aulas e atividades didáticas. Em muitas situações, professoras e professores realizaram atividades que descaracterizam sua identidade docente e conflitam com atividades domésticas, produzindo mal-estar e sofrimento. Em pesquisa de coorte em duas fases, o sofrimento psicológico de professores e professoras da Educação Básica foram analisados em função da quantidade de trabalho remoto, do gênero, da quantidade de trabalho doméstico e da experiência prévia. O trabalho remoto emergencial produziu efeitos na Ansiedade-estado, Afeto negativo e Estresse percebido − e essas respostas foram moderadas pela experiência prévia. Mulheres apresentaram maiores respostas que homens, um efeito mediado principalmente pela quantidade de trabalho doméstico realizada pela professora. Os participantes referenciaram principalmente dimensões laborais negativas e dimensões afetivas quando levados a pensar sobre o trabalho remoto, com menor saturação de respostas relacionadas a dimensões laborais positivas, à aprendizagem e a questões político-econômicas. Esses resultados sugerem que o trabalho remoto emergencial exacerba o estresse docente, apontando para precarização do trabalho docente e necessidade de implementação de políticas que mitiguem esses impactos.

Psychopathology has been criticized for decades for its reliance on a over-reductionist approach which views mental disorders as disease-like natural kinds that result from pathological changes in brain structure and function. The lack of progress in developing better treatments for mental disorders happened in spite of a great deal of research trying to uncover its neural bases. A new ontoepistemology for mental disorders is proposed, focusing on a biocultural model, in which brains are understood as embodied and embedded in ecosocial niches - zones of living within a milieu that can be occupied by a particular individual with its form of life, and with which brains enact particular transactions characterized by circular causality. In this approach, neurobiological bases are always-already associated with interpersonal, social, and cultural factors, and therefore are inseparable from these factors. As an ontoepistemology, this approach leads to methodological changes in how mental disorders are studied, as well as to consequences to interventions.

In one of his most important works, "Mutual Aid: A Factor of Evolution" (1902/2009), the Russian anarchist Pyotr Kropotkin outlined his ethnological and ethological observations that led him to propose that, although what later came to be called "fitness" in evolutionary biology is greatly influenced by competition between individuals, cooperation is also an important factor in the evolution of populations and species. Darwin (1859/2018) considered the problem of cooperation a difficulty for his theories, but it were his followers - especially Thomas Huxley and Herbert Spencer - who ignited a vigorous debate around the subject in the 19th century. Building on Helen Longino's epistemology, I argue that both approaches are value-laden and have political goals, from a libertarian approach in the Kropotkinian camp to a liberal approach in the Huxley-Spencerian camp. This value-ladenness represents an important feature of the Nature of Science that should not be neglected in science teaching, especially in the teaching of evolution. The debate promoted by Kropotkin can be used, in the classroom, to teach the role of cooperation in the evolution of species, as well as to discuss the role of the external context in establishing scientific objectivity, sensu Longino.

The present article uses the description of the "circulatory system" (sensu Latour) oftechno-science around COVID-19 - in particular regarding the development ofvaccines and scientific evidence on the treatment of symptoms - as a didacticproposition for Science Teaching, showing how current events can and should alsobe mobilized as substrate for the critical understanding of the Nature of Science inthe classroom. From the description of the various actors involved in the COVID-19event, we discuss how it is possible to articulate scientific knowledge and criticaldiscussions about the Nature of Science to mobilize scientific literacy - that is, themastery and internalization of a properly scientific way of looking at the natural andsocial worlds, while at the same time rejecting negationism and absolutism about asupposedly univocal and linear science. The COVID-19 event allows us tounderstand the role of supposedly "alien" actors to technosciences as part of thewhole "circulatory system", combining Latour's stance with feminist perspectives,such as Helen Longino's, on objectivity and inter-subjectivity, and how theseelements can be articulated to promote scientific literacy.

Introduction. In rats, long-term ovariectomy results in low concentrations of steroid hormones and reproduces anxiety- and depression-like behavior after surgical menopause in women. Progesterone produces antidepressant-like effects two weeks post-ovariectomy (i.e., early post-ovariectomy) through actions on γ -aminobutyric acid-A (GABA A ) receptors, but its antidepressant-like effects and mechanism of action in rats eight weeks post-ovariectomy (i.e., late post-ovariectomy, considered a model of surgical menopause) remain unknown. Objective. To explore the antidepressant-like effects of progesterone and the participation of GABA A receptors in rats eight weeks post-ovariectomy. Method. Long-term ovariectomized female Wistar rats were treated sub-acutely with vehicle or progesterone (.5, 1, and 2 mg/kg) and subjected to the open field and forced swim tests, and behavior was compared with cycling or fluoxetine-treated rats. The rats were then pretreated with picrotoxin (1 mg/kg) followed by progesterone (1 mg/kg) to explore the role of GABA A receptors in long-term-induced depression-like behavior. Results. Long-term ovariectomized rats exhibited depression-like behavior in the forced swim test compared with intact rats, an effect that was not observed in progesterone- and fluoxetine-treated long-term ovariectomized rats. These effects were not attributable to psychomotor alterations. In the open field test, the time spent rearing and grooming was lower in ovariectomized rats compared with intact rats, which was not observed in progesterone- and fluoxetine-treated rats. Picrotoxin blocked the effects of progesterone in both behavioral tests. Discussion and conclusion. These results indicated that sub-acute progesterone treatment reduced depression-like behavior through actions on GABA A receptors in a rat model of surgical menopause.

The two-factor theory predicts that the acquisition of avoidance responses is dependent on fear reduction; as such, drugs that reduce or increase fear or anxiety states should alter inhibitory avoidance (IA) acquisition. The present experiment used white spaces as aversive unconditioned stimuli in IA in zebrafish. Adult zebrafishes were tested in three experiments: validation of white compartment as aversive in IA; open field test; and effect of antidepressant (fluoxetine, imipramine) and anxiolytic (diazepam, clonazepam). The data show the effectiveness of the white compartment as an aversive stimulus in IA. Antidepressant fluoxetine did not alter and imipramine impairs avoidance acquisition in higher doses. Imipramine also produced a sedative effect in lower doses. Anxiolytic and stimulant drugs facilitated learning at doses which did not impair locomotion, suggesting that pharmacological manipulation of other factors in addition to fear/anxiety can impact aversive learning in zebrafish.

In guppies (Poecilia reticulata), a small number of individuals break away from a shoal and approach a potential predator, a behavior termed “predator inspection”. These animals often employ a “conditional approach” strategy, in which an individual approaches the predator in the first move and subsequently approaches it only if a second individual swims even with it during inspection. This strategy is analogous to the “tit-for-tat” strategy of the Prisoner’s Dilemma, suggesting that it could be used to study cooperation. Serotonin is thought to mediate cooperative behavior in other fish species. Exposure to the animated image of a predator in a tank that contained a parallel mirror – mimicking an equally cooperating conspecific – promoted inspection and decreased refuge use, but increased freezing, suggesting that conditional approach is also associated with fear. To understand whether serotonin participates in conditional approach in guppies, we treated animals with either vehicle (Cortland’s salt solution), fluoxetine (2.5 mg/kg) or metergoline (1 mg/kg), and tested then in a predator inspection paradigm. Fluoxetine increased the time the animal spent inspecting the predator image, while metergoline decreased it. Fluoxetine also decreased time spent avoiding the predator and increased freezing, while metergoline decreased freezing. These results suggest that phasic increases in serotonin levels promote conditional approach, suggesting a role for this neurotransmitter in cooperation.Preprint: https://doi.org/10.1101/436345; Data and scripts: https://github.com/lanec-unifesspa/TFT

Serotonin (5-HT) receptors have been implicated in responses to aversive stimuli in mammals and fish, but its precise role is still unknown. Moreover, since at least seven families of 5-HT receptors exist in vertebrates, the role of specific receptors is still debated. Aversive stimuli can be classified as indicators of proximal, distal, or potential threat, initiating responses that are appropriate for each of these threat levels. Responses to potential threat usually involve cautious exploration and increased alertness, while responses to distal and proximal threat involve a fight-flight-freeze reaction. We exposed adult zebrafish to a conspecific alarm substance (CAS) and observed behavior during (distal threat) and after (potential threat) exposure, and treated with the 5-HT2C receptor agonists MK-212 or WAY-161503 or with the antagonist RS-102221. The agonists blocked CAS-elicited defensive behavior (distal threat), but not post-exposure increases in defensive behavior (potential threat), suggesting inhibition of responses to distal threat. MK-212 blocked changes in freezing elicited by acute restraint stress, a model of proximal threat, while RS-102221 blocked changes in geotaxis elicited this stressor. We also found that RS-102221, a 5-HT2C receptor antagonist, produced small effect on behavior during and after exposure to CAS.Preprint:https://www.biorxiv.org/content/10.1101/2020.10.04.324202; Data and scripts:https://github.com/lanec-unifesspa/5-HT-CAS/tree/master/data/5HT2C

Os modelos são importantes componentes na atividade científica, porém suas funções são divergentes diante das várias vertentes da filosofia da ciência e epistemologia. Correntes como o realismo e antirrealismo discutem a importância dos modelos, colocando-os em patamares distintos. Ao mesmo tempo, é imprescindível compreender a visão sobre o uso dos modelos enquanto subsídios no ensino de ciências. O debate realismo/anti-realismo não representa uma mera curiosidade epistemológica, mas algo que têm consequências para a ciência escolar, entendida como um processo de transposição didática que, por necessidade, apóia-se em idealizações. Saídas para o problema são apresentadas, incluindo um foco nas transposições didáticas e na historiografia das ciências.

A utilização de problemas de aprendizagem é uma estratégia de ensino-aprendizagem ativa largamente utilizada em métodos e currículos diversos, do estudo de caso à aprendizagem baseada em problemas. Ao usar problemas como estímulo à atividade, o/a professor/a incentiva a aprendizagem autodirigida, o desenvolvimento de aspectos metacognitivos fundamentais, a aquisição de habilidades de resolução de problemas, e o interesse intrínseco. Descrevo um método para criar problemas em cursos de graduação em Psicologia, com base em experiências prévias em disciplinas de caráter biomédico (p. ex., Anatomofisiologia Aplicada à Psicologia) e de caráter mais crítico (p. ex., disciplinas relacionadas à saúde mental e à psicopatologia). O método parte da integração dos elementos da ementa da disciplina para movimentar perguntas geradoras de uma árvore temática. Proponho ainda a aplicação de métodos baseados na teoria da atividade para avaliar e calibrar o problema. O método proposto pode beneficiar tanto currículos integrados quanto disciplinas mais isoladas.

This protocol, modified from OECD 203 (Acute toxicity test, adult fish), tests toxic (lethal and nonlethal) effects of substances that have been injected intraperitoneally in adult fish. While OECD 203 is appropriate for testing the effects of waterborne substances (e.g., sewage effluents, pesticides, and other toxicants that can reach water bodies), the modified version can be added in a drug screening pipeline

The seminal characteristics of Moenkhausia oligolepis are described. Three males were induced with a single dose of carp pituitary. Semen was collected 6 h after induction, and diluted in dibasic sodium phosphate extender solution. For motility analysis, 1 µl of diluted semen was added to 10 µl of distilled water to achieve gamete activation. The average duration of total motility was 76.67 s; while the average sperm motility rate at intervals of 15 s was 95.3, 85.3, 59.6, 31.7, 13.0, 4.6 and 1.2%. To determine sperm concentration in samples, 0.5 μl of semen was diluted with 500 μl of glutaraldehyde. An aliquot of 10 μl of this dilution was utilized for cell counting. An average count of 4.97 × 109 ± 3.46 sperm/ml was obtained. Morphological analyses were performed using eosin-nigrosine dye; 20.33% of the sperm were observed to be dead. Live sperm, comprising the other 79.67%, had an average length of approximately 30 µm, with a head diameter of 4.488 ± 0.7 µm; and a flagella plus mid-piece length of 26.071 ± 12.4 µm. Of those sperm, 69% had a normal morphology, while 31% had primary and secondary abnormalities. The observed abnormality rate did not have a detrimental effect on artificial fertilization potential for the species. The description of the seminal characteristics of a species is one of the most important sets of information required for artificial reproduction of fish in captivity. It also contributes significantly to the total biological knowledge of the studied species.

The Open Practical Laboratory in the Neurosciences (OpenLN) is an outreach program that seeks to improve the knowledge of the neurosciences by elementary school students and to promote better attitudes in relation to neuroscience, science in general, and scientists. It consists in practical and demonstration activities on the theme of the neurosciences. This outreach strategy was applied in four public schools in a municipality in Southeastern Pará, Brazil characterized by low performance in educational reviews in Brazil. Students from both sexes from 9th grade (last grade before high school) were enrolled in the program. The outreach program improved students’ knowledge about the neurosciences, and promoted better attitudes in relation to science and scientists, in comparison to students which did not go through the activities. Results suggest that scientific outreach strategies can produce results beyond immediate increases in knowledge, promoting better attitudes in relation to science.

The industry is increasingly relying on fish for toxicity assessment. However, current guidelines for toxicity assessment focus on teratogenicity and mortality. From an ecotoxicological point of view, however, these endpoints may not reflect the “full picture” of possible deleterious effects that can nonetheless result in decreased fitness and/or inability to adapt to a changing environment, affecting whole populations. Therefore, assessing sublethal effects add relevant data covering different aspects of toxicity at different levels of analysis. Impacts of toxicants on neurobehavioral function have the potential to affect many different life-history traits, and are easier to assess in the laboratory than in the wild. We propose that carefully-controlled laboratory experiments on different behavioral domains – including anxiety, aggression, and exploration – can increase our understanding of the ecotoxicological impacts of contaminants, since these domains are related to traits such as defense, sociality, and reproduction, directly impacting life-history traits. The effects of selected contaminants on these tests are reviewed, focusing on larval and adult zebrafish, showing that these behavioral domains are highly sensitive to small concentrations of these substances. These strategies suggest a way forward on ecotoxicological research using fish.

The dopaminergic system of zebrafish is complex and the numerous pathways and receptors in the central nervous system (CNS) are being extensively studied. A critical factor for the synthesis, activation and release of catecholamines (CAs) is the presence of tyrosine hydroxylase, an enzyme which converts L-tyrosine into levodopa. Levodopa thus is the intermediary in the synthesis of dopamine (DA) and norepinephrine (NE) and promotes its release; therefore, CAs play an important role in the CNS with hormonal functions. Here, we use levodopa/carbidopa to clarify the involvement of the dopaminergic pathway in the stress response in zebrafish submitted to an acute stress challenge. Acute stress was induced by chasing fish with a net for 2 min and assessed by measuring whole-body cortisol levels. Two experiments were carried out, the first with exposure to levodopa/carbidopa and the second with exposure to AMPT and levodopa/carbidopa. Levodopa/carbidopa balances the stress response through its action on the zebrafish hypothalamic-pituitary-adrenal (HPA) axis. Changes in cortisol levels suggest that DA was related to the balance of the stress response and that NE decreased this response. These effects were specific to stress since levodopa/carbidopa did not induce changes in cortisol in non-stressed fish.

Nitric oxide has been implicated in symptoms of ethanol withdrawal in animal models. Zebrafish have been used as models to study neurobehavioral effects of ethanol (EtOH) withdrawal, but the mechanisms associated with these effects are not yet clear. Adult zebrafish were treated with 1% EtOH for 20 min per day for 8 days, injected with the nitric oxide synthase 2 (NOS-2) inhibitor aminoguanidine (50 mg/kg), and allowed to experience withdrawal (WD) in their hometanks for 7 days. EtOH WD increased anxiety-like behavior in the novel tank test, an effect that was blocked by aminoguanidine. EtOH WD also increased brain levels of nitrite, an effect that was partially blocked by aminoguanidine. These results underline a novel mechanism by which NOS-2 controls anxiety-like responses to ethanol withdrawal, with implications for the mechanistic study of symptoms associated with chronic ethanol abuse. Preprint: https://dx.doi.org/10.20944/preprints201912.0219.v1 Data and scripts: https://github.com/lanec-unifesspa/etoh-withdrawal/tree/master/NOS2

Stress is known to modulate behavioral responses and rapid decision-making processes, especially under challenging contexts which often occur in social and cooperative interactions. Here, we evaluated the effects of acute stress on cooperative behavior of the Indo-Pacific cleaner wrasse (Labroides dimidiatus) and the implications of pre-treatment with monoaminergic compounds: the selective serotonin reuptake inhibitor - fluoxetine, the 5-HT1A receptor antagonist - WAY-100,635, the D1 receptor agonist - SKF-38393, and the D1 receptor antagonist - SCH-23390. We demonstrated that stress decreased the predisposal to interact and increased cortisol levels in cleaners, which are alleviated by fluoxetine and the dopaminergic D1 antagonist. Overall, our findings highlight the crucial influence of stress on cooperative behavior.