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INTRODUCTION: The tribes Cophomantini, Scinaxini, and Dendropsophini are anurans that belong to Hylidae, with wide distribution in tropical and subtropical regions around the world. The taxonomy and systematics of this family remain in a state of ongoing revision. Previous cytogenetic analyses of genera Boana, Bokermannohyla, Ololygon, Scinax, and Dendropsophus described some karyotypic characters such as conventional staining, C-banding and NORs, and FISH with specific probes. METHODS: This study describes for the first time the karyotypes of four species: Bokermannohyla ibitipoca, Ololygon luizotavioi, Dendropsophus bipunctatus, and Dendropsophus ruschii. Furthermore, we map CA(15) and CAT(10) microsatellite sites for the aforementioned species and six more species from the same genera for insight into the chromosomal evolution within the subfamily Hyalinae. RESULTS: B. ibitipoca and O. luizotavioi had 2n = 24 and karyotypic formulas 18m + 4sm + 2st and 8m + 12sm + 4st, while D. bipunctatus and D. ruschii showed 2n = 30 and karyotypic formulas 12m + 12sm + 4st + 2t and 10m + 10sm + 6st + 4t, respectively. The diploid numbers and karyotypic formulas revealed here follow the previously reported trend for Hylidae, except B. ibitipoca has a particularity of eight metacentric chromosomes, more than what is commonly found in species of this genus. The microsatellites probes CA(15) and CAT(10) had markings accumulated in blocks in the centromeric, pericentromeric, and terminal regions that were more specific for some species, as well as markings scattered along the chromosomes. We present a comprehensive review table of current data on cytogenetics of these genera. CONCLUSION: Our findings showed that the karyotypes of the hylids studied here majority fit the postulated conserved diploid number (2n = 24) and morphological chromosome patterns, while the mapping of the microsatellites enabled us to detect differences between species that share similar chromosomal morphologies.

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O objetivo deste estudo foi avaliar os efeitos duradouros de dois tipos de estresse sobre o corpo caloso (CC). Foram estudados 42 ratos Wistar machos divididos aleatoriamente em três grupos: Grupo Controle (GC), Estresse Físico (EF, imobilização) e Estresse Psicológico (EP, exposição ao predador). Os procedimentos de estresse ocorreram durante três dias consecutivos na idade juvenil (P25-P27) e foram analisados na idade adulta (P74). Os cérebros foram coletados, processados com a técnica de Klüver-Barrera, e secções foram analisadas por meio de morfometria. Os resultados demonstraram que não houve alterações em aspectos gerais como peso dos animais, e histológicos como espessura do CC e quantidade dos núcleos gliais nesta região. O estudo sugere que os efeitos duradouros de ambos os modelos de estresse juvenil de curta frequência (3 dias) e intensidade (90 minutos/EF e 20 minutos/EP) não foram nem prejudiciais e nem protetores, o que pode ser considerado uma adaptação positiva.

The current study evaluates the lasting effects of two types of stress on the corpus callosum (CC). Forty-two male Wistar rats were randomly divided into three groups: Control Group (CG), Physical Stress (FS, immobilization) and Psychological Stress (PS, exposure to predators). Stress procedures occurred for three consecutive days at the juvenile stage (P25-P27) and analyzed at the adult age (P74); brains were retrieved and processed by Klüver-Barrera technique and sections were analyzed by morphometry. Results showed that there were no changes in the general aspects such as animal weight, and in the histological aspects such as CC thickness and quantity of the region´s glia nuclei. Current research suggests that the lasting effects of both models of juvenile stress of short frequency (3 days) and intensity (90 minutes/FS and 20 minutes/PS) were neither detrimental nor protective, featuring a positive adaptation.

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PURPOSE: During the juvenile stage, such areas as the hippocampus and corpus callosum (CC) are still immature and sensitive to stress exposure. The present study investigated whether two different types of stressors in the juvenile stage of life have a long-lasting impact on behavior and biological outcomes in adult rats. METHODS: Male juvenile rats were exposed to restraint or predator stress on postnatal day 25 (P25) for 3 days. Thirty-two days later (P60-74), behavioral and biological analyses were conducted. The behavioral analysis included measures of anxiety-like behavior and recognition memory. The biological analysis investigated gross cerebral morphology, based on volume analysis of the CC and hippocampus, perirhinal cortex thickness, and dendritic spine density. RESULTS: Neither restraint stress nor predator stress affected anxiety-like behavior or object recognition memory in adulthood. Body weight and adrenal gland weight were unaffected by both types of stress. Overall, volumetric measures of the CC and hippocampus were not significant, with no changes in perirhinal cortex thickness. Spine density in the medial prefrontal cortex also was unaffected, but a decrease in dendritic spine density was found in the hippocampus in response to restraint stress and an increase to predator stress. CONCLUSION: Short-term and daily restraint and predator stress during the juvenile stage had no long-lasting effects on anxiety-like behavior, object memory, volume of the CC or hippocampus, or perirhinal cortex thickness, but a decrease in dendritic spine density was found in the hippocampus. These findings suggest that different types of stressors have different impacts on microstructures in the brain without affecting behavior or the gross morphology of stress-sensitive brain areas.

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Recent phylogenetic hypotheses within Anostomidae, based on morphological and molecular data, resulted in the description of new genera (Megaleporinus Ramirez, Birindelli et Galetti, 2017) and the synonymization of others, such as the reallocation of Leporinus copelandii Steindachner, 1875 and Leporinus steindachneri Eigenmann, 1907 to Hypomasticus Borodin, 1929. Despite high levels of conservatism of the chromosomal macrostructure in this family, species groups have been corroborated using banding patterns and the presence of different sex chromosome systems. Due to the absence of cytogenetic studies in H. copelandii (Steindachner, 1875) and H. steindachneri (Eigenmann, 1907), the goal of this study was to characterize their karyotypes and investigate the presence/absence of sex chromosome systems using different repetitive DNA probes. Cytogenetic techniques included: Giemsa staining, Ag-NOR banding and FISH using 18S and 5S rDNA probes, as well as microsatellite probes (CA)15 and (GA)15. Both species had 2n = 54, absence of heteromorphic sex chromosomes, one chromosome pair bearing Ag-NOR, 18S and 5S rDNA regions. The (CA)15 and (GA)15 probes marked mainly the subtelomeric regions of all chromosomes and were useful as species-specific chromosomal markers. Our results underline that chromosomal macrostructure is congruent with higher systematic arrangements in Anostomidae, while microsatellite probes are informative about autapomorphic differences between species.

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Eukaryotic genomes contain large amounts of repetitive DNA sequences, such as tandemly repeated satellite DNAs (satDNAs). These sequences are highly dynamic and tend to be genus- or species-specific due to their particular evolutionary pathways, although there are few unusual cases of conserved satDNAs over long periods of time. Here, we used multiple approaches to reveal that an satDNA named CharSat01-52 originated in the last common ancestor of Characoidei fish, a superfamily within the Characiformes order, ∼140-78 Ma, whereas its nucleotide composition has remained considerably conserved in several taxa. We show that 14 distantly related species within Characoidei share the presence of this satDNA, which is highly amplified and clustered in subtelomeric regions in a single species (Characidium gomesi), while remained organized as small clusters in all the other species. Defying predictions of the molecular drive of satellite evolution, CharSat01-52 shows similar values of intra- and interspecific divergence. Although we did not provide evidence for a specific functional role of CharSat01-52, its transcriptional activity was demonstrated in different species. In addition, we identified short tandem arrays of CharSat01-52 embedded within single-molecule real-time long reads of Astyanax paranae (536 bp-3.1 kb) and A. mexicanus (501 bp-3.9 kb). Such arrays consisted of head-to-tail repeats and could be found interspersed with other sequences, inverted sequences, or neighbored by other satellites. Our results provide a detailed characterization of an old and conserved satDNA, challenging general predictions of satDNA evolution.

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Estresse é a resposta aos diferentes estímulos que o organismo sofre em busca de adaptação à homeostasia. Devido à sua alta incidência, diversos modelos experimentais estão sendo desenvolvidos para a melhor compreensão de sua inter-relação com outros órgãos. Neste contexto, o objetivo deste estudo foi avaliar os efeitos em longo prazo do estresse físico e psicológico juvenil agudo sobre as glândulas suprarrenais de ratos, no que se refere aos aspectos morfológicos, pois tais glândulas apresentam relação direta com situações de estresse. Para tanto, as glândulas suprarrenais destes animais foram processadas e análises morfológicas da medula e do córtex foram realizadas por meio de morfometria e quantificação por planimetria. Os resultados obtidos demonstraram que o estresse tanto físico quanto psicológico não provocaram alterações significativas em relação à área de superfície e espessura das suprarrenais, indicando adaptação dos animais aos fatores estressantes aqui estudados.

Stress is a response to different stimuli experienced by the organism for its adaption to homeostasis. Due to its high occurrence, several experimental models are being developed to understand better the interrelationships between these organs. Current paper evaluates long-term effects of juvenile physical and psychological stress on the suprarenal glands of rats with regard to morphological aspects. In fact, these glands have a direct relationship with stress conditions. Rats´ suprarenal glands were processed and their medulla and cortex were morphologically investigated through planimetry. Results show that physical and psychological stress failed to cause significant changes on the surface area and thickness of the glands. This fact showed adaptation of animals to the type of stress under analysis.

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We previously found that fish oil (FO) facilitated memory recovery in the absence of pyramidal neuron rescue after transient, global cerebral ischemia (TGCI). Fish oil preserved the expression of microtubule-associated protein 2 (MAP-2), suggesting a relationship between dendritic plasticity and memory recovery that is mediated by FO after TGCI. The present study examined whether postischemic treatment with FO prevents ischemia-induced loss of dendritic processes in remaining pyramidal neurons. The effects of FO on neuroplasticity-related proteins were also examined after TGCI. Rats were subjected to TGCI (15 min, four-vessel occlusion model) and then received vehicle or FO (300 mg/kg docosahexaenoic acid) once daily for 7 days. The first dose was administered 4 h postischemia. Golgi-Cox staining was used to evaluate dentrict morphology in the pyramidal neurons of hippocampus (CA1 and CA3 subfields) and prefrontal cortex (PFC). Neuronal nuclei protein (NeuN), brain-derived neurotrophic factor (BDNF), growth-associated protein 43 (GAP-43), synaptophysin (SYP), and postsynaptic density protein 95 (PSD-95) levels were measured by Western blot in both structures. Fifteen minutes of TGCI reduced consistently the length of dendrites, number of dendritic branches and dendritic spine density (average of 25%, 43%, 32%, respectively) 7, 14, and 21 days postischemia, indicating that they did not recover spontaneously. This outcome of TGCI was reversed by FO treatment, an effect that was sustained even after treatment cessation. The NeuN and BDNF protein levels were reduced in both the hippocampus and PFC, which were recovered by FO treatment. GAP-43 protein levels decreased after ischemia in the PFC only, and this effect was also mitigated by FO. Neither SYP nor PSD-95 levels were altered by ischemia, but PDS-95 levels almost doubled after FO treatment in the ischemic group. These data support our hypothesis that synaptic plasticity at the level of dendrites may at least partially underlie the memory-protective effect of FO after TGCI and strengthen the possibility that FO has therapeutic potential for treating the sequelae of brain ischemia/reperfusion injury.

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O trabalho consistiu na elaboração de uma bebida alcoólica fermentada de muruci, e caracterizar os seus parâmetros físico-químicos. Para isso foram elaboradas três formulações com concentrações de polpas a 5, 15 e 25%. A fermentação foi conduzida à temperatura ambiente com acompanhamento diário da acidez e pH durante 15 dias, sendo o teor alcoólico analisado ao término da fermentação. Nos produtos finais foram analisados: pH (3,33; 3,42; 3,1); glicídios totais (57,87; 48,14; 41,20%); acidez total (33,97; 40,18; 95,39 meq/L); extrato seco (77,37; 57,65; 49,29%); densidade (1,017; 1,010; 1,005) e teor alcoólico (7,6; 8,9; 9,7 %v/v). Os resultados obtidos mostraram boa adequação do fruto para a produção de bebida alcoólica fermentada.

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O trabalho consistiu na elaboração de uma bebida alcoólica fermentada de muruci, e caracterizar os seus parâmetros físico-químicos. Para isso foram elaboradas três formulações com concentrações de polpas a 5, 15 e 25%. A fermentação foi conduzida à temperatura ambiente com acompanhamento diário da acidez e pH durante 15 dias, sendo o teor alcoólico analisado ao término da fermentação. Nos produtos finais foram analisados: pH (3,33; 3,42; 3,1); glicídios totais (57,87; 48,14; 41,20%); acidez total (33,97; 40,18; 95,39 meq/L); extrato seco (77,37; 57,65; 49,29%); densidade (1,017; 1,010; 1,005) e teor alcoólico (7,6; 8,9; 9,7 %v/v). Os resultados obtidos mostraram boa adequação do fruto para a produção de bebida alcoólica fermentada.(AU)

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A acerola é rica em compostos bioativos dentre eles os carotenoides e o branqueamento é um pré-tratamento que pode vir ajudar na conservação. Portanto, o objetivo deste trabalho foi analisar o branqueamento a vapor e por imersão, a fim de avaliar qual o melhor tratamento na preservação dos carotenoides da acerola. Foi utilizado um planejamento experimental utilizando dois níveis de tempo e temperatura. O teor total de carotenoides obtido no tratamento por imersão degradou 44% desses pigmentos, enquanto que o processo à vapor degradou apenas 30%. Menores valores de tempo e temperatura, em ambos tratamentos conseguiram preservar maiores quantidades dos compostos bioativos, entretanto, o método de branqueamento a vapor, foi mais eficiente para preservação dos carotenoides totais.

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