Teses em Neurociências e Biologia Celular (Doutorado) - PPGNBC/ICB

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2390

O Doutorado Acadêmico pertence ao Programa de Pós-Graduação em Neurociências e Biologia Celular (PPGNBC) do Instituto de Ciências Biológicas (ICB) da Universidade Federal do Pará (UFPA).

Navegar

Agora exibindo 1 - 16 de 16

Acesso aberto (Open Access)
Ajustes motores compensatórios após lesão isquêmica focal unilateral do trato corticoespinhal
(Universidade Federal do Pará, 2017-06-30) CARVALHO, Walther Augusto de; BAHIA, Carlomagno Pacheco; http://lattes.cnpq.br/0910507988777644; PEREIRA JÚNIOR, Antônio; http://lattes.cnpq.br/1402289786010170
The aim of this work was to develop a new model of spinal cord injury caused by focal and unilateral transient ischemia after ET-1 microinjection in the dorsal funiculus and to evaluate the sensorimotor alterations of the anterior paw of rats (Wistar). Fifty (n = 50) animals (CEPAE / UFPA protocol BIO007912), who were trained, thirty-three (n = 33) were selected to compose control (n = 15), sham (n = 6) and injury (n = 12) groups. By using a micropipette, we injected the volume of 250 nL of saline (sham) or endothelin-1 (lesion) near the medial dorsal artery of the cervical segment C4 at a depth of 1 mm from the pial surface of the spinal cord. ET-1 induced cystic cavity formation of 0.421 mm2 (± 0.035 mm2, n = 3) on the corticospinal tract and suprajacent white matter, ipsilateral to the microinjection site that can be measured in cross-sections (50 μm) stained by the Nissl technique. The motor functions of the forepaw were evaluated by specific sensorimotor tests before and after injury at 3, 7 and 14 days. The results were evaluated by the ANOVA statistical test with Tukey post-hoc analysis (α = 0.05). Our results show in pasta test that after injury there is a compensatory motor behavior in which the non-preferential forepaw assumes the functions of the preferential forepaw. The Staircase test revealed a decrease in the ability to grasp the object with the preferred paw and the Contact test showed a decrease in sensitivity of the preferred paw.
Acesso aberto (Open Access)
Ajustes posturais antecipatórios e compensatórios em idosos com e sem lombalgia
(Universidade Federal do Pará, 2021-03) GARCEZ, Daniela Rosa; CALLEGARI, Bianca; http://lattes.cnpq.br/0881363487176703; https://orcid.org/0000-0001-9151-3896; YAMADA, Elizabeth Sumi; http://lattes.cnpq.br/7240314827308306
Chronic low back pain (DLC) is associated with changes in postural control and is highly prevalent in the elderly. Research shows that aging and DLC are described as important factors that affect postural control. The postural control impairments increase the risk of falls. Researches evaluating the postural control in elderly people with DLC are still necessary for greater effectiveness in balance rehabilitation programs to prevention falls in this population. The objective of this study is to verify whether anticipatory postural adjustments (APAs) and compensatory postural adjustments (CPAs) are affected by DLC in elderly people by assessing their postural control during a self-initiated perturbation paradigm induced by rapid upper arm movement when pointing to a target. Elderly people were divided into: Group with DLC (GDLC) (n = 15) and Control Group (CG) (n = 15). The participants’ lower limb muscle onset and center of pressure (COP) displacements were assessed prior to perturbation and throughout the entire movement. T0 moment (i.e., the beginning of the movement) was defined as the anterior deltoid (DEL) onset, and all parameters were calculated with respect to it. The rectus femoris (RT), semitendinosus (ST), and soleous (SOL) showed delayed onset in the GDLC group compared with the control group: RF (control: -0.094 ± 0.017 s; GDLC: -0.026 ± 0.012 s, t = 12, p < 0.0001); ST (control: - 0.093 ± 0.013 s; GDL: -0.018 ± 0.019 s, t = 12, p < 0.0001); and SOL (control: -0.086± 0.018 s; GDL: -0.029 ± 0.015 s, t = 8.98, p < 0.0001). In addition, COP displacement was delayed in the GDLC group (control: -0.035 ± 0.021 s; GDL: -0.015 ± 0.009 s, t = 3; p = 0.003) and presented a smaller amplitude during APA COPAPA [control: 0.444 cm (0.187; 0.648); GDLC: 0.228 cm (0.096; 0.310), U = 53, p = 0.012]. The GDLC group required a longer time to reach the maximum displacement after the perturbation (control: 0.211 ± 0.047 s; GDLC 0.296 ± 0.078 s, t = 3.582, p = 0.0013). This indicates that GDLC elderly patients have impairments to recover their postural control and less efficient anticipatory adjustments during the compensatory phase. Our results suggest that people with GDL have altered feedforward hip and ankle muscle control, as shown from the SOL, ST, and RT muscle onset. This study is the first study in the field of aging that investigates the postural adjustments of an elderly population with GDLC. Clinical assessment of this population should consider postural stability as part of a rehabilitation program.
Acesso aberto (Open Access)
Atividade neuroprotetora do treinamento físico moderado contra os danos morfofuncionais cerebelares causados pelo consumo de etanol de forma intensa e episódica (Binge drinking) em ratos
(Universidade Federal do Pará, 2019-09) VIEIRA, Kátia Lamarão; LIMA, Rafael Rodrigues; http://lattes.cnpq.br/3512648574555468; https://orcid.org/0000-0003-1486-4013
Ethanol (EtOH) is a psychotropic drug, central nervous system (CNS) depressant, but widely encouraged and consumed by Brazilian society, as well as in much of the world, reflecting on a public health problem. In recent decades, teenagers have been practicing a very common practice, which is binge drinking. The harmful consumption of EtOH promotes, besides biopsychosocial alteration, the homeostatic imbalance that causes neurodegeneration and loss of function with motor disorders. In contrast, the practice of moderate physical training (MPT) has been recommended for the maintenance of physical and mental health, as well as prevention or minimization of the development of some diseases due to motor activity inducing plastic and dynamic changes in the CNS, in order to favor the neurogenesis, synaptogenesis and angiogenesis, besides contributing to the synaptic modulation. In view of the benefits of MPT, it was investigated the neuroprotective effects on motor, tissue and biochemical parameters in the cerebellum of rats exposed to binge-pattern EtOH from adolescence to adulthood. Forty male Wistar rats with 30 days old were used and divided into four groups, the control being sedentary animals and treated with distilled H2O; the trained, composed of animals exercised and treated with distilled H2O; EtOH, formed by sedentary animals and treated with doses of 3 g/kg/day EtOH, 20% (w/v); and Trained + EtOH, with exercised animals and treated with doses of 3 g/kg/day EtOH, 20% (w/v). The MPT protocol was performed on a rodent treadmill for 5 days for 4 weeks and binge-pattern EtOH doses were administered by intragastric gavage in the same weeks as the MPT. After this period, the animals were submitted to open field and beam walking behavioral tests. Then, they were euthanized for cerebellum collection, evaluating immunohistochemistry from the levels of trolox equivalent antioxidant capacity (TEAC), reduced glutathione (GSH), nitrite and lipid peroxidation (LPO); as well as Purkinje cell morphology (PC), the fraction of anti-synaptophysine (SYP) and anti-myelin basic protein (MBP) immunolabeled area. According to the result, EtOH caused severe oxidative stress and motor damage, but the execution of the MPT performed promoted neuroprotective effects in the rat cerebellum, among them, the modulation of oxidative biochemistry by the restoration of GSH levels. decreased LPO levels and increased TEAC, as well as preventing neuronal loss, synaptic vesicle damage (SYP) and myelin components (MBP). Therefore, MPT can be considered as a significant therapeutic strategy for the acquisition of redox homeostasis, avoiding oxidative biochemistry imbalance, as well as tissue and functional damage in the cerebellum of rats treated by binge pattern EtOH.
Acesso aberto (Open Access)
Desenvolvimento de aplicativo para realização do finger tapping test e a influência do sexo e da dominância manual no desempenho do finger tapping test baseado em smartphone
(Universidade Federal do Pará, 2023-11) BRITO, Felipe André da Costa; SOUZA, Givago da Silva; http://lattes.cnpq.br/5705421011644718; https://orcid.org/0000-0002-4525-3971
The Finger Tapping Test (FTT) is a classical neuropsychological test that assesses motor functioning, and recently it has been employed using smartphones. For classical protocols, it has been observed that sex and handedness influence the performance during the test. By assessing the influence of sex and handedness on the test, it is possible to adjust the performance measurements to ensure the validity of test results and avoid sex- and handedness-related bias. The present study aimed to evaluate the influence of sex and handedness on smartphone-based FTT performance. We developed an Android application for the FTT and recruited 40 males and 40 females to carry out three spatial designs on it (protocols I, II, and III). Participants’ performance was measured using the global, temporal, and spatial parameters of the FTT. We observed that for the performance in protocol I, handedness had a significant influence on global and temporal variables, while the interaction between handedness and sex had a greater influence on spatial variables. For protocols II and III, we observed that handedness had a significant influence on global, temporal, and spatial variables compared to the other factors. We concluded that the smartphone-based test is partly influenced by handedness and sex, and these factors should be considered during the evaluation of the smartphone-based FTT.
Acesso aberto (Open Access)
Dinâmica de sucção disfuncional em lactentes com anquiloglossia
(Universidade Federal do Pará, 2023-11) CUNHA, Bruna Mendes Lourenço; SILVA FILHO, Manoel da; http://lattes.cnpq.br/2032152778116209
Introduction: Breastfeeding is widely recommended as an exclusive diet until 6 months of age and continued until two years or more. Its benefits are numerous and proven, including improving the immune system, a nutrient-rich diet and craniofacial development from the sucking movement. However, not all babies are able to breastfeed due to some difficulties, with ankyloglossia. Known as tongue tie, it can restrict tongue movements, making breastfeeding difficult and, in some cases, being responsible for early weaning. Objective: Compare infant suction in babies with and without ankyloglossia using a microprocessor-controlled pressure sensor coupled to a pacifier. Method: Fifty-five infants from 0 to 2 months of age underwent clinical examination for ankyloglossia, after which they were offered a silicone pacifier connected to the pressure acquisition device and suction activity was recorded. Thus, we extracted the frequency of sucks within a burst, the average suck duration, the burst duration, the number of sucks per burst, the maximum amplitude of sucks per burst and the inter-burst interval. Results: The key difference in newborns with ankyloglossia in relation to control was that they perform longer bursts of suction activity. Conclusion: The longer burst durations are likely a compensatory strategy and may underlie the pain reported by mothers during breastfeeding. We therefore propose a method for objectively quantifying some parameters of infant suction capacity and demonstrate its use in assisting the evaluation of ankyloglossia.
Acesso aberto (Open Access)
Efeito da competência leitora nas estratégias de organização perceptual da cena visual em escolares
(Universidade Federal do Pará, 2023-02) RESQUE, Deusa Priscila da Silva; MATOS, Felipe de Oliveira; http://lattes.cnpq.br/4207066833785568; https://orcid.org/0000-0002-4926-4694; PEREIRA JUNIOR, Antonio; http://lattes.cnpq.br/1402289786010170; https://orcid.org/0000-0002-0808-1058
The current Brazilian educational scenario, evaluated by different national and international indicators, has shown alarming results in mathematics, science and especially in reading. The country is in the last positions in all evaluations. For the change of this scenario, urgent educational measures that respect the student's biological and social development are necessary. The applied neurosciences to education emerge as a theoretical model of aid for pedagogical practices that aim to improve quality in education. An important contribution of neurosciences in education is focused on reading, through a theoretical/practical contribution on brain functioning those points more effective paths for literacy with a view to reading competence. In this sense, it was possible to understand that the human species has not yet developed a specific neural system for reading, using other brain structures for this function, ie literacy depends on a neural recycling process of brain structures associated with Sensory, motor and language functions, as is the case with brain regions associated with faces recognition, to accommodate the decoding of the written word. The aim of this study is to investigate reading in school -age children. To this end, the present thesis divided into two studies: Study 1 that investigates the inhibition of the generalization of letters in mirror in school -age children and the study 2 that investigates the relationship between reading competence and perceptual organization strategies of the visual scene in schools . Both studies were conducted in three public schools in the Belém do Pará Metropolitan Region, Brazil. Altogether two hundred and thirty -one subjects aged 6 to 10 years (113 boys, 8.2 ± 1.4 years and 118 girls, 8.2 ± 1.4 years), enrolled 1 to 5th years, were recruited, 1,2 ± 1.4 years old) elementary School. Among these eighty -eight subjects were students from school 1, fifty -two from school 2 and ninety from the school 3. In all, six tests were applied, each school participated in a different group of tests. Our results show that the performance of boys in the 6-10 year old is different from that of girls in the same age group for the reading competence test, with boys with higher performance, although it is not possible to establish differences between genders to the perceptual closure test. What's more, while boys performed significantly better in the rotation of letters in the older group, girls' performance was similar in both groups. This pattern is reverse for the mirror's task, with the older girls surpassing their younger counterparts and the boys performing similarly in both groups. Since the age period of our sample is not associated with large variations in reproductive steroid levels, we propose that the similarity of performance between younger and older girls in the mental rotation of letters may be associated with society's traditional attitudes and expectations and expectations about the relationship between spatial visual skills and gender. As for the mirror's task, while only girls showed a significant difference between the two age groups, the boys showed improvement, as expected by the mirror generalization inhibition to letters during reading. These findings are relevant to the development of more effective future strategies for optimizing the literacy process of school -age children, combining education and neuroscience. For this, more studies must be performed and the number of subjects investigated should be expanded.
Acesso aberto (Open Access)
Estudo do desenvolvimento auditivo da habilidade de fusão binaural
(Universidade Federal do Pará, 2022-04) ARAÚJO, Francisca Canindé Rosário da Silva; SILVA FILHO, Manoel da; http://lattes.cnpq.br/2032152778116209
Introduction: Binaural Interaction (BI) allows the introduction of auditory information (in the brain as a function of differences in perception of intensity or time of acoustic stimuli). Allows you to assess the action and integrated co- operative of the brainstem in lower understanding. As the maturation of the central nervous system occurs in the craniocaudal direction, the response to this ability may change during the course of development. Objectives: To normalize and compare the development with increasing age of response in the binaural diffusion test (BPT) with digital low-pass (LP) and high-pass (HP) filters in normative listeners. Methods: Prospective, cross-sectional and observational study. A total of 120 years were evaluated, in different age groups (6 to 8 years old, 10 to 12 years old, 14 to 16 years old and 20 to 30 years old) with TFB, filter at Fc 500/1700 Hz digital Finite Impulse Response type order 4096, with null phase and 5000 between 18 and 30 years with unfiltered speech material. Results: a progressive improvement in performance with increasing age (ANOVA (one-way): p<0.0001). There was a significant difference between the filtered words, age and the unfiltered p < (Dunnet: any filtered words,01). The difference between the age groups was significant (Tukey: p<0.01), less for the results obtained in the age groups of 6-8 and 10-12 years and of 14-16 and 18- 30 years. Discussion: IB is a skill that evolves with age development and NC fabrication. Final considerations: The interpretation of the TFB should take into account the performance by age group of the patients. This is important for future applications of these tests in people with Auditory Processing Disorder.
Acesso aberto (Open Access)
Estudo eletrorretinográfico da adaptação à luz de vias de processamento específicas de cone e de oponência em cor e luminância
(Universidade Federal do Pará, 2017-12-15) COSTA, Alódia Brasil; SILVA, Anderson Manoel Herculano Oliveira da; http://lattes.cnpq.br/8407177208423247
Visual system has an essential function called light adaptation or photopic adaptation, which consists in the regulation of light sensitivity allowing visual adaptation to a wide range of illumination levels. This phenomenon is not fully elucidated. Therefore, the present study aims to evaluate the magnitude and temporal pattern of the variation of retinal electrical responses for L cone and M cone selective stimuli and for luminance pathway and red-green color pathway specific stimuli, making possible the evaluation of the red-green parvocellular (P pathway) and magnocellular (M pathway) visual pathways activity, during the photopic adaptation. For such purpose, 6 healthy subjects underwent 30 minutes of dark adaptation and then were exposed a light steady background for 16 min. The stimuli were given every 2 min and the electrical retinal response was recorded by full field electroretinogram (ffERG) over 16 min. The triple silent substitution method was used to isolate the responses of pathways originating from the L or M cone. We also used specific stimuli of luminance (Lum) and red-green color (Crom). For each stimulation type was used intermediate (12 Hz, which reflects the activity of the red-green parvocellular pathway - P pathway) and high (36 Hz, which reflects the activity of the magnocellular pathway - M pathway) temporal frequency, resulting in 8 stimulation conditions. Amplitude and phase of the first (F), second (2F) and third (3F) harmonic components were extracted by Fast Fourier Transform. It was observed that amplitude and phase increased over light adaptation time with simple sine wave form in the most of components and stimulation conditions. The relative increases in F amplitude from the M-cone driven responses during the light adaptation were higher than those L-cone driven ERGs at both temporal frequencies, 12 Hz (M = 1.21, L = 0.33) and 36 Hz ( M = 1.94, L = 0.55), as well as they were higher at 36 Hz than at 12 Hz for the two cones. In general, there was slight F phase increase during the light adaptation time (<30 degrees), slightly higher at 36 Hz. Regarding the light adaptation kinetics, F amplitude and phase that seem reflect the activity of the P pathway presented a faster adaptation (L-cone 12 Hz, M-cone 12 Hz, Crom 12 Hz, Lum 12, with a mean of 1.4 min) and those that probably reflect activity of the M-pathway had slower adaptation (Lum 36 Hz, L-cone 36 Hz, M-cone 36 Hz, with a mean of 4.9 min). Thefore, M and P pathways presented different magnitude and kinetics of light adaptation, being the M pathway the pathway of greatest increase and slower adaptation.
Acesso aberto (Open Access)
Expressão gênica durante o desenvolvimento ocular e regulação de assimetria de opsinas na espécie Anableps anableps, peixe de quatro olhos
(Universidade Federal do Pará, 2022-11) SOUSA, Daniele Salgado de; SCHNEIDER, Patrícia Neiva Coelho; http://lattes.cnpq.br/9584217233879031
The ocular development is a complex process orchestrated by several events that include: cell specification, morphogenesis and differentiation. All these developmental and functional processes are extremely conserved among living vertebrate species, however, unique adaptations are sometimes observed, such as in fish of the genus Anableps. Unlike most fishes, which use their eyes to explore a submerged world, in Anableps anableps (Anablepidae: Cyprinodontiformes), the eye is adapted for the simultaneous perception of a world above and below the water line. These exceptional adaptations include: duplicated corneas and pupils, as well as a specialized retina region associated with simultaneous aerial and aquatic vision, and which have asymmetrical gene expression. Recently, by transcriptomic analysis of the developing eyes of A. anableps, 20 non-visual opsin genes were identified to be asymmetrically expressed between pre- and post-duplication stages of corneas and pupils. Thus, here, we analyzed by in situ hybridization the gene expression of a bistable opsin (parapinopsin) and a neuropsin (Opn5) in A. anableps larvae. Our data showed that the pattern of gene expression of these opsins is symmetrical between the dorsal and ventral retina, respectively, with expression in the ONL, INL and GCL layers. We also investigated the expression of three non-visual melanopsin genes (opn4x1, opn4x2, opn4m3), one eleost multiple tissue opsin (tmt1b), and two visual opsins (lws and rh2-1) in the dorsal and ventral retinas of juvenile A. anableps, after changing the photic conditions in which the juvenile fish were. Then, we showed that in the transition from an environment of high turbidity to one of clear water, opsins have their expression patterns changed. Additionally, by immunofluorescence, we revealed the expression of Lamin A/C, proteins expressed as part of eye development in A. anableps as well as in other developing organisms, as well as in adult individuals. Therefore, we believe that the information described here elucidates many aspects of the molecular mechanisms behind the development and adaptive plasticity of A. anableps’ eyes.
Acesso aberto (Open Access)
O extrato aquoso de Coriandrum sativum L. promove neuroproteção contra alterações motoras e danos oxidativos na progênie de ratas expostas ao metilmercúrio
(Universidade Federal do Pará, 2020-01) RODRIGUES, Keuri Eleutério; PRADO, Alejandro Ferraz do; http://lattes.cnpq.br/7016475842644161; NASCIMENTO, José Luiz Martins do; http://lattes.cnpq.br/7216249286784978; https://orcid.org/0000-0003-3647-9124
This study aimed to investigate the efects of Coriandrum sativum aqueous extract (EACS) on the rat progeny of mothers exposed to methylmercury (MeHg). The presence of bioactive compounds and EACS's antioxidant capacity been evaluated, and the spring were assessed for their total mercury levels, motor behavioral parameters and oxidative stress in the cerebellum. The analysis of the bioactive compounds revealed significant amounts of polyphenols, flavonoids, and anthocyanins, as well as a variety of minerals. A DPPH test showed the EACS had important antioxidant activity. The MeHg + EACS group performed significantly better spontaneous locomotor activity, palmar grip strength, balance, and motor coordination in behavioral tests compared the MeHg group, as well as in the parameters of oxidative stress, with similar results to those of the control group. The MeHg + EACS group alsohad significantly reduced mercury levels in comparison to the MeHg group. Based on the behavioral tests, which detected large locomotor, balance, and coordination improvements, as well as a reduction in oxidative stress, we conclude that EACS had positive functional results in the spring of rats exposed to MeHg.
Acesso aberto (Open Access)
Função de recuperação do nervo auditivo após doze meses de uso do implante coclear
(Universidade Federal do Pará, 2022-03) YAMAGUCHI, Cíntia Tizue; SILVA FILHO, Manoel da; http://lattes.cnpq.br/2032152778116209
Introduction: Cochlear implant is the standard treatment for severe and profound bilateral sensorineural hearing loss. To optimize the adaptation of this device, especially in patients who do not have the ability to refer to the parameters necessary for programming, such as children and people with associated disabilities, objective tests based on the action potential of auditory nerve fibers have been studied as possible predictors. of these parameters to be used in cochlear implant programming. The auditory nerve recovery function is a test that measures the time the auditory nerve needs to recover from a stimulus (leave the absolute refractory period) to receive new stimulation and possibly be more responsive to the auditory sensation offered by the cochlear implant. Objective: Through a specific software for cochlear implants, with the objective of measuring the time constant (τ) in the intraoperative period and in the postoperative period after 12 months of cochlear implant use in children. Method: We recruited children with cochlear implant and intraoperative neural response, evaluated the recovery function using commercially available cochlear implant software. Data were collected intraoperatively and repeated twice 12 months after surgery. Results: We found that the recovery time of the auditory nerve increases after 12 months of cochlear implant use. Our results also show that the profile of temporal responses is significantly higher in the postoperative measurement than in the intraoperative one. The test-retest reproducibility of the composite evoked action potential recordings proved to be reliable and stable. Conclusion: There was a change in 12 months of cochlear implant use, in relation to the same measure at the intraoperative moment in the subjects of this study. The intraoperative τ measurement was faster, however, in the postoperative period the mean showed higher τ values. However, the current level was different intraoperatively and 12 months after use, needing to be further explored. There was no statistical difference regarding the test-retest in the postoperative period, showing reliability and reproducibility of the measurement. Possibly it would be the beginning of the study of a responsiveness profile in relation to the recovery time of the auditory nerve.
Acesso aberto (Open Access)
Método baseado me cromatografia líquida de alta eficiência para analisar a atividade dos transportadores de GABA no sistema nervoso central
(Universidade Federal do Pará, 2022-08) MORAES, Edinaldo Rogério da Silva; SILVA, Anderson Manoel Herculano Oliveira da; http://lattes.cnpq.br/8407177208423247
The GATs are the membrane proteins responsible for the uptake of GABA in the central nervous system. Alterations in GAT activity are implicated in several neurological diseases, including retinopathies. The present study describes an alternative method to determine GAT activity in tissue preparations of the central nervous system, using high performance liquid chromatography (HPLC) with fluorescence detection. The GABA concentration in the medium was determined using the o-phthaldehyde (OPA)-derivation protocol validated by the Brazilian Health Regulatory Agency (ANVISA) and the United States Food and Drug Administration (US-FDA). The GAT activity in the retinal preparations was determined through the evaluation of the GABA uptake, which was measured by assessing the difference between the initial and final concentrations of GABA in the incubation médium (Δ𝐺𝑎𝑏𝑎 = [𝐺𝑎𝑏𝑎] 𝑡_0 − [𝐺𝑎𝑏𝑎] 𝑡_𝑒𝑛𝑑). The evaluation of the GAT kinetics returned values of Km = 382.5 ± 32.2 μM and Vmax = 34 nmol/mg of protein. The data also demonstrated that the GABA uptake was predominantly Na+ and temperature-dependent, and was also inhibited by incubation with nipecotic acid, a substrate of GABA transporters. Taken together, these findings confirm that our approach provided a specific measure of GAT activity in retinal tissue. The data presented here thus validate, for the first time, an alternative, simple and sensitive method for the evaluation of GAT activity using high performance chromatography on preparations of the central nervous system.
Acesso aberto (Open Access)
Pez-cebra (Danio rerio) como modelo de bienestar animal
(Universidade Federal do Pará, 2022-10) VASQUEZ, Jhon Jairo Buenhombre; GOUVEIA JUNIOR, Amauri; http://lattes.cnpq.br/1417327467050274; https://orcid.org/0000-0003-1710-9662
Zebrafish has become an important model for various disciplines such as neuroscience and the testing of new pharmacological molecules. Therefore, the way in which it is housed and the consequences of its accommodation on its well-being represent an important aspect to study. Very few studies have evaluated the effect of environmental enrichment on the welfare of zebrafish and its negative or positive impacts have yet to be elucidated. An important challenge is to establish the consequences not only of the presence of enrichment but also of its loss. Likewise, the form of presentation of a stimulus, either predictably or unpredictably, influences the physiological and behavioural responses of the animal. Therefore, the form of presentation of the enrichment represents another important aspect to assess. The evaluation of emotional (affective) states is crucial for the study of zebrafish welfare, in particular to evaluate the influences of the environment on the animal. However, directly assessing these states is difficult due to their subjective nature. Therefore, the current approach focuses on estimating them from the resulting physiological and behavioral components. Today there are robust standardized tests that assess and correlate neuroendocrine responses with well-established behavioural assessment criteria for stress and anxiety in zebrafish. However, there are no similar tests to measure positive emotional states in this species. An alternative metric to assess both the positive and negative affective states of animals is the cognitive bias. These tests allow researchers to infer an individual's emotional state from cognition. Therefore, the evaluation of apparently negative (Unpredictable conditions and absence or loss of enrichment) and positive ones (Predictable conditions and presence or gain of enrichment) accommodation contrasts through a type of cognitive bias (cognitive judgment bias (CJB) in zebrafish may constitute a promising model to understand the effects of housing on affective states and well-being in this fish. Additionally, it has been shown that individual variations such as personality influence the central nervous system, behaviour and cognitive judgment bias results in other species. These differences and their impacts on zebrafish have not yet been studied. Consequently, the general objective of this thesis was to establish if the cognitive judgment bias can be used in zebrafish for the evaluation of positive and negative emotional states produced by environmental modifications and its relationship with personality.
Acesso aberto (Open Access)
Semelhanças cognitivas inesperadas entre idosos e jovens: variabilidade e desempenho cognitivo
(Universidade Federal do Pará, 2023-08) JARDIM, Naina Yuki Vieira; TORRES, Natáli Valim Oliver Bento; http://lattes.cnpq.br/1927198788019996; https://orcid.org/0000-0003-0978-211X; DINIZ, Cristovam Wanderley Picanço; http://lattes.cnpq.br/2014918752636286
Interindividual variability in cognitive performances has been investigated as they may provide important clues about the multivariate age-related cognitive decline. In the present work, we searched for cognitive variability, similarities, and differences between older and young people. For this, we used hierarchical cluster and canonical discriminant function analysis of cognitive scores using specific and sensitive tasks from the Cambridge Neuropsychology Test Automated Battery - CANTAB. Among 415 tested volunteers, three distinct cognitive groups were found, mainly based on working memory and episodic memory scores: group 1 (94% young adults) was composed almost exclusively of young adults, while groups 2 (82% older adults) and 3 (95% older adults) were composed predominantly of older adults. Although group 1was the youngest group with the highest level of education compared to the other groups, 18% of young people shared similar performances with older group 2 while 5% shared cognitive similarities with group 3. As compared to group 1, predominantly older groups 2 and 3 had equally lower scores in working memory, but as compared to group 3, group 2 showed greater performances in reaction time, sustained attention, and episodic memory. When the hierarchical cluster and discriminant function analyzes were limited to the same age group, we found 4 and 5 distinct clusters among young adults and older people respectively. Episodic memory, sustained attention, and reaction time most contributed to group formation in the older, while working memory and sustained attention contributed to cluster formation of young adults. Cognitive variability across subjects showed significant dispersion in rapid visual processing, spatial working memory, reaction time, and paired associated learning. The comparative analysis of these differences showed that they do not occur in the same direction and magnitude between individuals, cognitive domains, and tasks. We found that older adults with greater education and a more active lifestyle must have greater cognitive reserve and, therefore, deviated less from the reference group of young adults. Taken together, our data highlight the importance of studying variability as an instrument for the early detection of subtle cognitive declines and to interpret results that deviate from normality.
Acesso aberto (Open Access)
A tomada de decisões no judô: o que se diz e o que se faz? Relação entre tomada de decisões e perfil neurocognitivo
(Universidade Federal do Pará, 2023-03) RIVERA, Luis Felipe Sarmiento; GOUVEIA JUNIOR, Amauri; http://lattes.cnpq.br/1417327467050274; https://orcid.org/0000-0003-1710-9662
There are two ways to think about how the decision process is done. The process can be automatic and having psychomotor characteristics, or mediated by linguistic process -in a deliberated way-. Moreover, martial arts bring an environment with high emotionality, where the anxiety is present. The objective of this study is to understand how the decision-making process, the anxiety and the impulsivity is presented in a combat physical activity, a Judo fight, that demands constant decisions and responses with limited time. To do this, there were to groups of participants (30 judo fighters and 15 non-fighters). One of the groups watch a video and anticipated the fighter’s movement with a questionary, and the other group was recorded in a judo fight. Both groups also performed an impulsivity test and an anxiety test. Each participant had more than 4,5 years of training and was an active competitor. There were found differences in the decisions made by the participants in the fight and the decisions that the participants told they would perform, specifically, when they were going to execute and action. Moreover, there was a significant difference in the anxiety levels of the group of fighters compared to controls, where the fighters had higher anxiety levels than controls. There were none significative differences in impulsivity between the groups. The results of the study shown how is cognition in Judo fighters, indicating where to focus the training and competition programs of the fighters.
Acesso aberto (Open Access)
Topografia de células ganglionares alfa na retina de roedores da Amazônia
(Universidade Federal do Pará, 2022-05) SAMPAIO, Gabriela Santos Alvarez; SOUZA, Givago da Silva; http://lattes.cnpq.br/5705421011644718; https://orcid.org/0000-0002-4525-3971
Introduction: The visual system of Amazonian rodents of the suborder Hystrichomorpha has been widely described, but little is known about the topography of alpha ganglion cells, which play a role in processing the vision of moving stimuli. Agouti (Dasyprocta aguti), paca (Cuniculus paca) and capybara (Hydrochoerus hydrochaeris) rodents are three different species of Hystrichomorpha that have a different circadian cycle and lifestyle. Objectives: To quantify alpha ganglion cell density and analyze cell body size according to eccentricity in the retina of agouti, paca and capybara. Methods: Three agouti, paca and capybara retinas from the pre-existing retinal collection at the Eduardo Oswaldo Cruz Laboratory of Neurophysiology at UFPA were used. Retinal collection were stained by the Nissl corpuscle staining method and direct counting was performed under a Zeiss optical microscope. The density of alpha-like ganglion cells was analyzed in different retinal eccentricities, such as in the visual range, area centralis, dorsal and ventral regions. Result: Analyzing the entire retina, the mean density of alpha-like ganglion cells in the agouti was 94.7±5.05 cells/μm2, in the paca it was 28.7±2.03 cells/μm2 and in the capybara it was 28.7±2.03 cells/μm2. of 101.03±24.42 cells/μm2. The presence of areas with high density of alpha ganglion cells was observed in the temporal region of the retina of the three rodents, and the agouti was the species that showed the most accentuated specialization of this type of ganglion cells. The cell body area of alpha ganglion cells that showed the highest frequency in the agouti retina was 200 μm², in the paca retina it was 300 to 600 μm² and in the capybara it was 300 to 500 μm². Conclusion: It is concluded that there is a relationship between ecology and density of alpha ganglion cells in the retina of large Brazilian rodents, so that those with diurnal habits have retinas with a greater number of these cells and with greater specialization in the temporal region.

Navegar

Navegando Teses em Neurociências e Biologia Celular (Doutorado) - PPGNBC/ICB por Linha de Pesquisa "NEUROFISIOLOGIA"