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Gameta masculino de mico-leão-de-cara-dourada (Leontopithecus chrysomelas): parâmetros reprodutivos seminais e epigenéticos
(Universidade Federal de São Carlos, 2015-09-23) Watanabe, Isabela Midori; Valle, Rodrigo Del Rio do; https://lattes.cnpq.br/2879780464444096; Peripato, Andréa Cristina; https://lattes.cnpq.br/0657713343451089; https://lattes.cnpq.br/9807949412364479
The Golden-headed lion tamarin (Leontopithecus chrysomelas) is an endemic monkey to Atlantic Forest. Nowadays, they are classified as threatened of extinction. Efforts on its conservation cover in situ and ex situ programs, and the application of the biotechnology of reproduction could assist populational manegement, hence ensuring the maintence of genetically healthy populations. Therefore, it is necessary to understand species reproductive characteristics, such as seminal parameters and variables that could influence them, and also the epigenetic mechanisms involved on genomic imprinting - once they are associated with reproductive success, and alterations on its patterns have been correlated with assisted reproduction technics. In the present study we investigated seminal and molecular parameters of golden-headed lion tamarins’ male gametes that are kept in captivity at São Paulo Zoological Foundation. Two main groups were outlined: seniors (mean age of 148.17 months; n=6) and young (mean age=50.14 months; n=6). Considering all animals, we could not find influence of weight on seminal parameters, as oppose to inbreeding coefficient variable, that showed negative correlation with total motility (R= -0.380, p<0.001), progressive motility (R= -0.443, p<0.001) and plasmatic membrane integrity (R= -0.270, p=0.018). Among seminal parameters, we found positive correlations between progressive motility and total motility (R=0.859, p=0.001), progressive motility and acrosome integrity (R=0.631, p=0.041), acrosome integrity and plasmatic membrane integrity (R=0.629, p=0.042). In addition, we found negative correlation between seminal pH and concentration (R= -0.612, p=0.029). There was only significant difference between seminal pH considering seniors and young males (t(9)=2.45, p=0.04), in which the seniors showed more alkaline pH. Molecular parameters investigated on these primates semen involved methylation analysis of two maternal imprinted genes: PEG3 and PEG1/MEST. Based on Callithrix jacchus genome, we inferred genes and its CpG islands to study them in L. chrysomelas. Through bisulfite sequencing, we investigated these regions of PEG3 and PEG1/MEST aiming to analyze putative DMRs. Among sampled animals, we could not find methylation differences on these regions, wherein all samples showed hypermethylated PEG3 region, and hipomethylated PEG1/MEST region. PEG3 CpG island is located in an exon, suggesting it is not involved in an imprinting control region. However, PEG1/MEST CpG island locates at a promoter region, showing hipomethylaton -as expected-, and align with PEG1/MEST promoter in humans, which could indicate a potential DMR. Our results are insipient to draw a conclusion about these imprinted genes in L. chrysomelas, but it was relevant as an initial approach to contribute to populational manegement of golden-headed lion tamarins kept in captivity.
O autorrelato de crianças expostas a contingências de competição e cooperação em atividades computadorizadas
(Universidade Federal de São Carlos, 2015-09-23) Oliveira, Marlon Alexandre de; Rose, Julio Cesar Coelho de; https://lattes.cnpq.br/3386857761295187; https://lattes.cnpq.br/6854732327669497
The present research investigated whether contingencies of competition and/or cooperation, that could be set up on two distinct tasks (music and computer game) would affect the levels of accurate and non-accurate reports by typical children about their performances during those tasks. “Do” consisted in requiring children to play a computerized game or naming musical melodies while “say” consisted in reporting if the trial terminated with a hit or with a miss. Twelve typical children with ages ranging from seven to 11 years old were assigned to two groups with three kids for Experiment 1. Experiments 2 and 3 comprised one group with three children each. During baseline sessions from all the experiments points were presented contingent upon performances on both tasks. After the baseline, the competition contingency was on for Experiments 1 and 3 while cooperation contingency was on for Experiment 2 for its related task (music or game). Baseline contingency was still on for the other task. After some sessions the competition or cooperation contingency was set up to the other task too, thus an inter-task multiple baseline was achieved. On Experiment 3, cooperation contingency was set up for both tasks simultaneously. The points earned for correct responding on the competition contingency was exchanged by tokens that could be exchanged by gifts at the end of the session in depending of the child’s place on a rank (first place, second place and third place). The child that obtained the first place was given the chance to exchange tokens for the most preferred among the other reinforcers that were available. Children that obtained the second and third places were given chance to exchange tokes for the less preferred reinforcers only. On the other hand, the cooperation contingency specified that tokens could be exchanged by the most preferred reinforcers only if children consented in putting their tokens together. For four out of six participants the say-do correspondence decreased when the competition contingency was set up (Experiment 1). But, when cooperation contingency was set up on Experiment 2, the say-do correspondence increased for three children. It is important to notice that the increase on the levels of correspondence was observed only when cooperation contingency was set up for both tasks and not when this contingency was set up for only one task, while the other was under the same contingency as for baseline condition. Performances on the tasks and the levels of say-do correspondence were disturbed by the competition contingency during Experiment 3. This means that levels of say-do correspondence was altered while the accuracy on both tasks decreased. And the onset of the cooperation contingency resulted in increase of say-do correspondence for only one participant (music). It seems fair to assume that shifting a competition to a cooperation contingency can affect the performances on the tasks. But because of the variability on the data obtained on Experiment 2, it not possible to infer to which extent the disturbance in say-do correspondence can be attributed to shifts on contingencies or to the deterioration on task performances. In general, data from all experiments strongly suggests that the levels of say-do correspondence tend to be different when these behavior are measured under competition or cooperation contingencies. Future studies should verify the measurability of say-do correspondence in different experimental designs that could permit a more stringent experimental control over critical variables.