Dissertações em Neurociências e Biologia Celular (Mestrado) - PPGNBC/ICB

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2375

O Mestrado 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 - 20 de 227

Acesso aberto (Open Access)
Receptor A2A de adenosina modula o transporte de glutamato independente de sodio em cultura primaria de celulas da retina
(Universidade Federal do Pará, 2024-11) LIMA, Caroline Araujo Costa de; OLIVEIRA, Karen Renata Herculano Matos; http://lattes.cnpq.br/3032008039259369
Dysregulation of extracellular glutamate levels is directly associated with several CNS pathologies, highlighting the importance of glutamate transporters in maintaining tissue homeostasis and developing new therapeutic approaches. The retina is particularly vulnerable toexcitotoxic events due to its high levels of glutamate extracelular and the frequente exposure to oxidative stimuli, reinforcing the need for regulatory mecanisms to preserve retinal physiology. In this context, adenosine emerges as an essential neuromodulator, exhibiting regulatory effects that are concentration- and receptor-dependent. Therefore, the objetive of this study was to characterize the effect of adenosine on sodium-independent glutamate transport in retinal cell culture. As such, mixed primary cell cultures from White leghorn chick embryos (E7-E8) were maintained for 7 days in DMEM+10% FBS at 37°C and 5% CO₂. The cells were submitted to apre-incubation with an A2A receptor blocker and incubated with different adenosine concentrations for glutamate release and uptake assays. Glutamate levels were quantified by HPLC, and protein levels were measured by the Bradford method, with equimolar substitution of NaCl by LiCl. Furthermore, immunofluorescence with an anti-xCT antibody and the nuclear marker DAPI was used to identify the sodium-independent glutamate transporter, with image analysis performed using ImageJ e Photoshop CS6. Statistical analysis was conducted using Student’s test T and ANOVA one-way with Tukey post-hoc test via GraphPad 9.0, with data expressed as percentage of control±S.D. with p<0,05. The results confirmed the expression of the xCT subunit, indicating that the system xCG-is the sodium-independent glutamate transporter in retinal cells. Additionally, adenosine at a concentration of 50μM increased glutamate release by approximately 800%, while glutamate sodium-independent uptake was completely inhibited.These effects were fully by A2A receptor blockade. Therefore, we demonstrated that activation of the A2A receptor modulates glutamate sodium independent transport, whose
Acesso aberto (Open Access)
Avaliação dos níveis extracelulares de GABA e glutamato no sistema nervoso central de camundongos infectados com Plasmodium berghuei ANKA
(Universidade Federal do Pará, 2024-11) LIMA, Renato Mateus Santos de; OLIVEIRA, Karen Renata Herculano Matos; http://lattes.cnpq.br/3032008039259369
Cerebral malaria (CM) caused by Plasmodium falciparum results in high mortality, especially in children under 5, with up to 25% of survivors experiencing neurological sequelae such as cognitive impairment and seizures. The neurochemical mechanisms behind these impairments are not well understood. This study aimed to characterize changes in the levels of the neurotransmitters glutamate (GLU) and γ-Aminobutyric acid (GABA) in the central nervous system (CNS) during experimental cerebral malaria (ECM). ECM was induced in Swiss mice with Plasmodium berghei ANKA (PbA), and the animals were monitored for parasitemia, survival, and neurological impairments using the Rapid Murine Coma and Behavior Scale (RMCBS). On the 7th day post-infection (d.p.i), blood-brain barrier (BBB) disruption was assessed using Evans Blue dye, and glial cell evaluation was performed by immunofluorescence. Results showed that PbA-infected mice began to succumb to CM by the 6th d.p.i, with 100% mortality by the 10th d.p.i. Behavioral impairments were observed from the early stages of infection. Significant BBB permeability changes and increased expression of glial activation markers were noted in infected mice. There was a marked increase in GLU levels in the brain and cerebellum on days 3, 5, and 7 post-infection. GABA levels increased on days 3 and 5, returning to control levels by day 7. These findings indicate significant neurochemical alterations in GABAergic and glutamatergic neurotransmission, accompanied by neurological and vascular impairments, suggesting their involvement in the development of neurological symptoms in CM.
Acesso aberto (Open Access)
Modelo de hemiparkinsonismo por 6-hidroxidopamina em primatas Sapajus apella: características comportamentais e histológicas
(Universidade Federal do Pará, 2024-10) PEDROSA, Laís Resque Russo; KREJCOVÁ, Lane Viana; http://lattes.cnpq.br/2604693973864638; GOMES, Bruno Duarte; http://lattes.cnpq.br/4932238030330851
Despite considerable side effects and decreasing effectiveness over time, the treatment for Parkinson's disease (PD) has remained largely unchanged for over 50 years. However, several aspects of the disease's pathophysiology remain poorly understood. The development of new therapies and the elucidation of mechanisms related to the disease are among the biggest current challenges in neuroscience research. In this context, non-human primate (NHP) experimental models are particularly relevant due to their high phylogenetic proximity, encephalization rate, and complex motor and behavioral repertoire, confer high predictive power for clinical outcomes. The 6-hydroxydopamine inoculation model of parkinsonism mimics relevant features of PD and may represent an important experimental refinement in primates. The present study aimed to develop a model of hemiparkinsonism induction in Sapajus apella primates, characterizing the behavioral and histological aspects. For this purpose, adult male Sapajus apella monkeys were subjected to motor tests to observe motor performance before and after unilateral injection of 6-OHDA in the nigrostriatal pathways at concentrations of 4 (N=1), 10 (N=1) and 40 (N=1) mg/μl in the dominant hemisphere. As a surgical control (N=1), one animal underwent surgery containing only solvent. Stereotaxic coordinates for the 12 6-OHDA inoculation sites were calculated based on individual Magnetic Resonance Imaging (MRI) images. Immunohistochemistry for tyrosine hydroxylase (TH) was performed on 50 μm coronal sections of the midbrain. As a statistical analysis, two-way ANOVA was used to verify possible differences in behavioral parameters and neuronal exclusion between groups, considering the dominant (therefore affected) and non-dominant hemispheres. There were significant changes in motor patterns of dominance and manual preference after surgical intervention. 6-OHDA induction in the nigrostriatal pathways appears to be a good method of inducing parkinsonism with the induction of detectable symptoms in primates.
Acesso aberto (Open Access)
Caracterização química, avaliação da toxicidade oral aguda e da atividade antinociceptiva do extrato metanólico das folhas de Montrichardia linifera (Arruda) Schott
(Universidade Federal do Pará, 2024-08) COSTA, Wellington Junior Taisho Nagahama; AMARANTE, Cristine Bastos do; http://lattes.cnpq.br/4101983776191966; https://orcid.org/0000-0002-8602-8180; BASTOS, Gilmara de Nazareth Tavares; http://lattes.cnpq.br/2487879058181806
Background: Montrichardia linifera (Arruda) Schott is popularly known as “aninga”, “aningaçu”, “aningaíba” and “aninga-do-igapó”. The compresses and plasters from the leaves of the medicinal plant are used to treat abscesses, tumors and pain caused by stingray stings. Aim of the study: The study aimed to investigate the antinociceptive potential of the methanolic extract of Montrichardia linifera leaves (MEMLL), as well as carry out chemical characterization and acute oral toxicity. Materials and methods: The leaves were collected during the rainy season and the methanolic extract was obtained after gradient extraction in different solvents. The MEMLL was analyzed using high performance liquid chromatography (HPLC) and Nuclear Magnetic Resonance (NMR). The evaluation of the acute oral toxicity test was used to observe the presence of toxic substances. Subsequently, acetic acid, hot plate and formalin tests were used to evaluate the analgesic effects. Results: The HPLC fingerprint analysis allowed the identification of rutin, quercetin and epicatechin. The analysis of NMR spectra identified rutin and quercetin, as well as the flavonoids luteolin and chrysoeriol. The MEMLL did not demonstrate effects considered toxic. In the acetic acid test, the MEMLL inhibited peripheral pain by 51.46% (p < 0.05) at a dose of 50 mg/kg and 75.08% (p < 0.001) at a dose of 100 mg/kg. The hot plate test evaluated the latency time of animals, demonstrating central activity at 30 and 60 min increasing by 164.43% (p < 0.01) and 122.95% (p < 0.05) at a dose of 50 mg /kg and 162.62% (p < 0.01) and 136.68% (p < 0.05) at a dose of 100 mg/kg. The formalin test evaluated the central and peripheral antinociceptive effect of the MEMLL. In the neurogenic phase, a reduction of 35.25% (p < 0.05) at a dose of 50 mg/kg and 52.30% (p < 0.01) at a dose of 100 mg/kg. In inflammatory pain, a reduction of 66.39% (p < 0.0001) and 72.15% (p < 0.0001) was observed. Conclusion: The antinociceptive activity supports its ethnopharmacological use. This analgesic effect is probably associated with the identified flavonoids, all of which have antioxidant, anti-inflammatory and antinociceptive properties. Furthermore, the MEMLL was non-toxic.
Acesso aberto (Open Access)
Pesquisa de hanseníase em doadores de sangue
(Universidade Federal do Pará, 2024-11) JORGE, Erika Vanessa Oliveira; PALMEIRA, Mauricio Koury; http://lattes.cnpq.br/2785104508455046; SALGADO, Claudio Guedes; http://lattes.cnpq.br/2310734509396125
Hansen’s disease (HD) is an infectious disease with active transmission in endemic areas such as Brazil, which accounted for over 90% of the new HD in the Americas in 2021, and the second highest in the global scale. Clinically is characterized by the appearance of nerve or skin lesions with altered sensitivity, that in advanced cases, can cause deformities and physical disabilities. Its transmission occurs mainly through Mycobacterium leprae, through respiratory droplets of sick people, and has a prolonged incubation period. The diagnosis of leprosy is clinical, with multidrug treatment PQT (polychemotherapy) being crucial to avoid the chain of disease transmission. Suspected cases should be attended by a qualified professional in basic health units or active case finding campaigns. Although leprosy patient is considered definitively unfit for blood donation process, according to Consolidation regulation nº 5, of October 3, 2017, leprosy investigation occurs only through a clinical interview, without laboratory evaluation. At Hemocenter from Pará, 500 donors were selected for the study and blood was collected for serological investigation of anti-PGL-I antibodies. Of the selected donors, 4% (20/500) had positive serological results greater than or equal to 0,750 optical density among only eight agreed to be clinically examined and underwent other laboratory tests: bacilloscopy and qPCR. Among donors with clinical evaluation, more than half were diagnosed with leprosy, 62.5% (5/8), with the following cases: one individual with the primarily neural clinical form, three with borderline-tuberculoid, one lepromatous. of peripheral blood, the presence of the bacillus in two individuals was confirmed, suggesting a possible route of transmission of the disease. We emphasize that the prevalence of subclinical leprosy infection due to its etiological agent among the study population is very high, but compatible with the hidden prevalence already recorded in the state of Pará.
Acesso aberto (Open Access)
Impacto da busca ativa especializada no diagnóstico da hanseníase: avaliação longitudinal e comparativa de aspectos clínicos e laboratoriais em áreas endêmicas no Pará e no Maranhão
(Universidade Federal do Pará, 2024-08) COSTA, Izabelle Laissa Viana; COSTA, Patrícia Fagundes; http://lattes.cnpq.br/6487407290759330; SALGADO, Claudio Guedes; http://lattes.cnpq.br/2310734509396125
Leprosy is a disease that represents a significant public health problem in various parts of the world, including Brazil. To improve epidemiological data, active case finding activities and longitudinal research represent a transformative approach to disease control. In this context, the present study aimed to evaluate and compare the clinical and laboratory aspects of patients with leprosy, their contacts, and schoolchildren over a one-year period in endemic areas in Pará and Maranhão. To achieve this, a longitudinal study was conducted, characterized by active case finding activities in Imperatriz-MA, São Luís-MA, and Marituba-PA, where registered leprosy cases in the Notifiable Diseases Information System (SINAN), their contacts, and school-aged children were evaluated. Participants underwent neurodermatological evaluation and blood collection for the titration of IgM anti-PGL-I antibodies, as well as intradermal scraping of the earlobes and elbows for bacilloscopy and qPCR. After one year, in 2023, participants from the municipalities of Imperatriz and São Luís were re-evaluated, and new participants were included. Among 522 individuals included in this study, 135/522 (25.9%) were clinically and/or laboratorially re-evaluated in 2023, and 387/522 (74.1%) were evaluated exclusively in 2022 or 2023. In 2022, new cases were identified among 66/221 (29.9%) contacts and 23/195 (11.8%) schoolchildren. Additionally, 9/34 (26.5%) relapses and 2/34 (5.9%) patients with therapeutic insufficiency or failure were diagnosed among index cases. In 2023, new cases were observed among 70/126 (55.5%) contacts and 10/29 (34.4%) schoolchildren. Furthermore, 7/12 (58.3%) relapses and 1/12 (8.3%) patients with therapeutic insufficiency or failure were diagnosed among index cases. In the neurodermatological evaluation, among schoolchildren and contacts who were re-evaluated, individuals with an altered superficial fibular nerve were found to be 4.3 times more likely to be in the disease case group (p < 0.05; 95% CI = 1.58- 12.74; OR = 4.32). The bacilloscopy test identified the etiological agent in 7/222 evaluated individuals (3.1%), with 4/7 (57.1%) being among individuals with a prior diagnosis of leprosy. Regarding the serological analysis of re-evaluated individuals, seropositivity was observed in 26/106 (24.5%) individuals in 2022, and 7/106 (6.6%) in 2023, a statistically significant decrease (p < 0.05). A high positivity rate for the qPCR technique was observed, including 9/10 (90%) relapses, 55/88 (62.8%) new cases, and 43/151 (48.3%) contacts. These data highlight a concerning scenario characterized by a high number of hidden leprosy cases in the analyzed regions, and a significant increase in diagnosis rates after one year of follow-up in the communities, underscoring the importance of longitudinal research and the implementation of different diagnostic and monitoring techniques for a better understanding of leprosy and its outcomes in endemic areas.
Acesso aberto (Open Access)
Estressores agudos distintos produzem diferentes magnitudes do comportamento tipo de ansiedade e liberação diferencial de glutamato no cérebro de zebrafish
(Universidade Federal do Pará, 2024-08) MARTINS, Milena Letícia; SILVA, Anderson Manoel Herculano Oliveira da; http://lattes.cnpq.br/8407177208423247; https://orcid.org/0000-0003-4022-8096
Anxiety disorder is one of the most well characterized behavioral disorder in individuals submitted to acute or chronic stress. However, few studies have demonstrated how different types of stressors can modulate the neurochemical alterations involved in generation of anxiety. In the present study, we hypothesize that subjects exposed to different aversive stimuli (mechanical, chemical and spatial restriction) present varied intensity of anxiety-like behavior response associated with distinct pattern of GABA and Glutamate release in the brain. Sixty adult Danio rerio animals were randomly divided into four experimental groups: Control (CTRL), Acute Restraint Stress (ARS), Conspecific Alarm Substance (CAS) and Chasing with Net (CN). After applying the stress protocols, the animals were individually transferred to the Novel Tank Diving Test for behavioral analysis. Subsequently, their brains were collected and subjected to GABA and Glutamate release assay for quantification by HPLC. Our behavioral results showed that all aversive stimuli were capable of inducing anxiety-like behavior. However, the impact of anxiogenic behavior was more prominent in the CN and CAS groups when compared to ARS. This phenomenon was evident in all analyzed behavioral parameters (time on top, freezing, mean speed, maximum speed and erratic swimming). Our data also have shown that all aversive stimuli induced significant decrease in GABA release when compared to the control group. On the other side, only animals exposed to CN and CAS presented increase in extracellular glutamate levels. Different acute stressors induce different intensity of Anxiety-like behavior in zebrafish as well as they provoke specific alterations on the GABAerigic and Glutamatergic release in the brain. These results demonstrate the complexity of anxiety disorders, highlighting that both behavioral and neurochemical responses are highly context-dependent, supporting our initial hypothesis.
Acesso aberto (Open Access)
Efeitos da terapia motora baseada em movimentos de dança nas funções da teoria da mente e do ritmo Mu de pessoas com doença de Parkinson
(Universidade Federal do Pará, 2023-08) VILHALVA, Jade Thalia Rodrigues; KREJCOVA, Lane Viana; http://lattes.cnpq.br/2604693973864638; BAHIA, Carlomagno Pacheco; http://lattes.cnpq.br/0910507988777644; https://orcid.org/0000-0003-3794-4710
Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects brain regions whose neural circuitry is responsible for controlling voluntary movements. In addition to motor symptoms, PD patients have non-motor symptoms that drastically affect their quality of life. These include cognitive alterations, among which deficits in working memory, deficits in executive functions and in the ability to deduce the mental states of others (Theory of Mind: ToM) stand out, and may also be related to the functions of mirror neurons (MN). The MN are neurons activated when a person performs or observes a given action, thus performing “internal” simulation of the observed acts, a necessary process for the ability to recognize emotions and intentions in the ToM. Their activity is influenced by prior training of observed motor actions and can be recorded using electroencephalography (EEG) through changes in the Mu band wave amplitudes (alpha 1 waves) detected when an individual observes the actions of another person. The present work investigated the effects of motor therapy on electroencephalographic activity and its correlations with MT functions in patients affected by PD. For this purpose, electroencephalographic evaluations were performed to investigate desynchronization patterns characteristic of mirror neuron activity, in addition to the Reading the Mind in the Eyes (RME) and Faux Pas Recognition (FPR) tests. We evaluated patients diagnosed with PD (n=09), under pharmacological regimen, Hoehn and Yahr 2-4, of both sexes and with mean age of 62.9 ± 7.1 years and mean of 5.8 ± 1.3 years of diagnosis , in time windows before joining the project after twelve months of participation in 2 weekly sessions of motor therapy in dance. Tabulated data were analyzed using Student's t-test. No significant differences were observed in the evaluation parameters of the FPR test in the Test and Retest temporal windows, whereas in the RMT test the average score obtained by the participants in the Test was 9.7 points, while in the Retest the average was 11.3 points with observed significance (p=0.0148), whereas electroencephalographic statistical analysis (TRPs) showed significant results in the level of desynchronization of alpha 1 waves (p=0.014 and p=0.010) during specific electrophysiological evaluation. The data showed that although the individuals did not show improvement in performance in most components of the analyzed TM tests, the electrophysiological results indicate alteration of specific cortical activity related to the activation of the mirror neuron system, influenced by motor therapy in dance, which may configure then, as an adjuvant therapeutic option in the management of motor and non-motor symptoms of PD.
Acesso aberto (Open Access)
Avaliação neuropsicológica de deficits cognitivos em pessoas vivendo com HIV (PVHIV)
(Universidade Federal do Pará, 2024-08) GONÇALVES, Samilly Palheta; RODRIGUES, Anderson Raiol; ROCHA, Fernando Allan de Farias; http://lattes.cnpq.br/3882851981484245; https://orcid.org/0000-0002-6148-1050
The introduction of antiretroviral therapy resulted in a reduction in opportunistic infections associated with HIV, consequently reducing the incidence of most neurological diseases in HIV-positive patients. However, neurocognitive changes associated with HIV (HAND) remain at a significant prevalence, even in individuals using antiretroviral drugs. The present study aimed to evaluate possible cognitive deficits in HIV-positive patients and characterize the clinical profile of neurocognitive manifestations in the Northern region of Brazil. 30 HIVpositive patients were evaluated, treated at the Health Care Center for Acquired Infectious Diseases (CASA DIA), in Belém do Pará. It was possible to verify a decline in neurological functions, which affect the functional capacity of these PLHIV, with emphasis on the cognitive domain of memory and attention, where it was possible to identify through IADLs, IHDS and CANTAB.
Acesso aberto (Open Access)
Efeito do óleo da espécie vegetal Caryocar villosum em linhagem de células vero in vitro
(Universidade Federal do Pará, 2024-08) LOPES, Izabella Carla Silva; NASCIMENTO, José Luiz Martins do; http://lattes.cnpq.br/7216249286784978; https://orcid.org/0000-0003-3647-9124
Fibroblasts are cells that participate in different processes in the body, being indispensable in the development and homeostasis of tissues. They are important agents in the healing process, being present in the inflammatory, proliferative and remodeling phases. These cells produce biomolecules that constitute the extracellular matrix, such as collagen, which provide the necessary support for healthy healing. However, healing is a complex process, and it is proneto failure, so it´s important to investigate therapeutic alternatives to produce more effective treatments in cases where natural healing is not effective. Natural products from plants are widely used as therapeutic forms for healing considering their lower side effects, low cost, this combined with traditional knowledge makes it attractive to studies that prioritize valuing biodiversity. Caryocar villosum (Cv), a fruit native to the Amazon region, is a remarkable source of bioactive compounds with therapeutic potential that has cosmetic and pharmaceutical applications. In this work, the action of Cv oil (CvO) on VERO cell line (fibroblast-like cells)was investigated. The cells were treated with 75, 125 and 250 μg/mL for 24 hours. Cytotoxicity assays, optical microscopy, cell proliferation, morphological analysis, and analysis of extracellular matrix components, such as phalloidin staining and immunofluorescence for type III collagen antibody, were performed. Any cytotoxicity was observed in the cells after CvOtreatment. CvO treatment induced morphological and physiological changes in the cells indicating cell activation. Fluorescence microscopy revealed greater cell spreading, rearrangement of actin filaments and increased cell surface exposure compared to untreated cells. Furthermore, this study suggests that fibroblasts treated with CvO are activated through cytoskeletal rearrangement, increasing cell surface, proliferating, and increasing collagen synthesis. These findings indicate that CvO may be a good therapeutic strategy from biodiversity to stimulate the healing process.
Acesso aberto (Open Access)
Tecnologia de processamento de imagem para orientação de deficientes visuais dentro do espaço residencial
(Universidade Federal do Pará, 2024-03) ABDON, Leonardo Miranda; SILVA FILHO, Manoel da; http://lattes.cnpq.br/2032152778116209
This work seeks to develop a product of assistive technology based on the Raspberry Pi platform in order to allow greater autonomy inside residential spaces for individuals with blindness. Therefore, it was assembled a wearable obstacle detection and path orienting system that uses a camera to capture images directed to the floor immediately in front of the user, in order to identify QR codes created specifically to generate responses within the written algorithm, so that responses are emitted through vibratory patterns in motors and recorded sentences through headphones. The system was developed in this way in order to allow autonomy in the choice of paths by the user with the aid of a low-cost assistive technology product, easily accessible and maintainable, and flexible in regard to the user's needs and preferences. The system’s capabilities were tested in a fixed setup inside a controlled study room without windows and in a movable setup in a controlled corridor, and the results were satisfactory regarding to the detection distances of paths and obstacles and the swiftness of emission of responses. Finally, a body vest made with bag straps was designed and the developed system was installed into it, to be used as a simple and nonintrusive wearable device.
Acesso aberto (Open Access)
Classificação de perfis de produtividade usando redes neurais artificiais a partir de registros eletroencefalográficos: uma aplicação na Mineradora Vale S.A., Complexo S11D Eliezer Batista
(Universidade Federal do Pará, 2024-01) BASTOS, Caio de Oliveira; PEREIRA JUNIOR, Antonio; http://lattes.cnpq.br/1402289786010170; https://orcid.org/0000-0002-0808-1058; GOMES, Bruno Duarte; http://lattes.cnpq.br/4932238030330851
Results and methods from neuroscience can already be applied on a routine scale. Applied neuroscience is in use, for example, to measure and study brain activity under high demand using electroencephalography (EEG). In certain work environments, human productivity is a direct function of brain activity. The intense recruitment of cognitive functions such as sustained attention and working memory influence productivity directly. The labor demands experienced by workers in mining companies are an example. This work is a part of a bigger project called “Usando Treinamento Cognitivo para o Desenvolvimento de Operadores de Alto Desempenho” from the Vale S. A. mining company and, therefore, all of the workers that participated in this study worked for that company. We used EEG to measure productivity during a task without the constraints typically found in experiments conducted in the laboratory. To this aim, we created a machine learning algorithm to analyze the resting EEG recorded before and after a 4D simulation, where mining workers (37 ± 7 years old) specialized to operate giant high-capacity shovels. The simulated task consisted of the operator using the shovel in a digging and loading routine. The task was not planned for our research. It was part of the worker’s routine training. That is, we took advantage of the workers’ training to carry out the study. Recordings were preprocessed using a band-pass filter (0.5-100 Hz) followed by filtering using ICA (Independent Component Analysis). After each operator finish the simulation, their productivity was measured by VALE S.A technical staff. The main parameter for good productivity was the amount of ore excavated. The operators were divided into groups according to ranges of productivity. The productivity was used as a label for the learning of the algorithm that consisted of an artificial neural network of the type inception. The number of neurons and layers was optimized using Bayesian optimization. The features extracted by the inception were the input to 13 classifiers. The classifier chosen for the final algorithm was the best, that is the one providing the best accuracy in the productivity classification. The training set contained 80% of the data. A hold-out validation was used to test the accuracy of the final algorithm using 20% of the data. The resulting accuracy when the operators were divided into four groups of productivity reached 91.35%. When there were only two groups of productivity the accuracy peaked at 95.05%. Our results showed that even under no laboratory constraints – during the regular training of the operators and using resting EEG – our algorithm succeed and it is ready to be used in future field operations. We have a prototype that is patentable.
Acesso aberto (Open Access)
Relação entre simetria facial e expertise artística na preferência estética por faces
(Universidade Federal do Pará, 2022-03) MONTEIRO, Luis Carlos Pereira; TEIXEIRA, Rachel Coêlho Ripardo; http://lattes.cnpq.br/7663300976857946; https://orcid.org/0000-0003-0515-7560; SOUZA, Givago da Silva; http://lattes.cnpq.br/5705421011644718; https://orcid.org/0000-0002-4525-3971
Visual symmetry is almost universally present in both natural and artificial environments. Its importance is on both perceptual and cognitive levels. Symmetry processing, especially bilateral symmetry, is fast, efficient, and noise resistant. Humans, like other species, prefer symmetrical visual stimuli, a preference that is influenced by factors such as age, sex, and artistic training. In particular, artistic training in visual arts seems to decrease the rejection of asymmetry in abstract stimuli. But it is not known whether the same trend would be observed concerning concrete stimuli, such as human faces. In this work, the role of expertise in visual arts, music, and dance, in the perceived beauty and attractiveness of human faces with different asymmetries was investigated. With this objective, the beauty and attractiveness of 100 photographs of faces (50 male and 50 female) with different degrees of asymmetry were evaluated by 116 participants with different levels of art expertise. The art expertise in the three artistic modalities mentioned was assessed through an Arts Expertise Questionnaire. Facial asymmetry was obtained from geometric morphometric techniques in the MorphoJ software. Multilevel modeling strategies (ANOVA for repeated measures, correlation for repeated measures and linear mixed models) were used for statistical analysis. Expertise in visual arts and dance was associated with the extent to which facial asymmetry influenced the beauty ratings assigned to the faces. The greater the art expertise in visual arts and dance, the more indifferent to facial asymmetry the participant was to evaluate beauty. The same effect was not found for music and neither for attractiveness ratings. These findings are important to help understand how face aesthetic evaluation is modified by artistic training and the difference between beauty and attractiveness evaluations.
Acesso aberto (Open Access)
Avaliação in vitro do potencial genotóxico e citotóxico do extrato do açaí (Euterpe oleracea) clarificado sobre a linhagem celular AGP01 (câncer gástrico)
(Universidade Federal do Pará, 2024-01) SANTOS, Thiago Souza; BAHIA, Marcelo de Oliveira; http://lattes.cnpq.br/3219037174956649; BURBANO, Rommel Mario Rodríguez; http://lattes.cnpq.br/4362051219348099; https://orcid.org/0000-0002-4872-234X
Açaí (Euterpe oleracea MART) is a fruit of great importance for the Amazon region in nutritional, cultural and socioeconomic terms. In recent years, açaí has been the subject of several studies due to its beneficial properties for health, including effects against tumor cells. Therefore, the present work aimed to evaluate in vitro the genotoxic and cytotoxic effects of the clarified extract of açaí juice in a human metastatic gastric cancer cell line (AGP01 cells). For comparison purposes, a non-transformed cell line of African green monkey renal epithelial cells (VERO cells) was used. The viability assay by resazurin reduction, the comet assay, the determination of cell death by differential fluorescent dyes and the wound healing migration assay were performed. A reduction in viability was observed only in the AGP01 line within 72h. There was no genotoxic damage or cell death (through apoptosis or necrosis) in any of the cell lines. However, açaí extract induced motility reduction in both cell lines. The reduction in cell viability and the induction of the anti-migratory effect in the AGP01 cell line opens perspectives for exploring the potential of Euterpe oleracea as an adjuvant in the treatment of gastric cancer.
Acesso aberto (Open Access)
Efeito do tratamento combinado com laserterapia e gel de açaí na fase proliferativa de reparo em modelo de lesão por ruptura tendínea total em ratos
(Universidade Federal do Pará, 2023-08-13) MENDES, Aurea Gabriela Rodrigues; MORAES, Suellen Alessandra Soares de; http://lattes.cnpq.br/6278397231382779; BATISTA, Evander de Jesus Oliveira; http://lattes.cnpq.br/2206444845201080
Acai extract has been investigated as a pharmacological strategy due to its anti- inflammatory, antioxidant and antinociceptive effects. Furthermore, studies report that low-intensity laser (LBT) may favor tissue repair due to its proliferative effects in increasing the number of fibroblasts and collagen synthesis. Therefore, the combined use of açaí with LBT may be a therapeutic alternative in the management of tendon repair. The aim of this study was to evaluate the effects of combined treatment with açaí gel and LBT on the morphofunctional and nociceptive aspects of Achilles tendon injury in the proliferative phase of repair. For this, 40 Wistar rats were divided into control group (CTRL), injury (INJURY), 10% açaí gel (INJURY+GA), 2J infrared laser, (INJURY+LAS) and combined treatment (INJURY+LAS+GA). The Von Frey test, Joint Angle and Achilles Functional Index were performed at 0-, 3-, 7- , and 14-days post-injury (DPL). After 14 days, the tendons were collected and the tissue organization pattern was analyzed by H&E or Alcian Blue to assess variations in glycosaminoglycans in the extracellular matrix, staining with DAPI to quantify the number of cells and collagen autofluorescence to assess the orientation pattern of collagen fibers. We demonstrated improvement in the macroscopic characteristics of the tendon in the treatment groups in relation to INJURY, which may be correlated with better organization and tissue orientation, as well as collagen fibers in these groups. The increase in the number of cells and fibroblasts was more evident in the laser group, emphasizing the proliferative role of the laser. Functional recovery was observed in 7 DPL in the isolated laser group, while the combined treatment improved nociception in the acute phase (7th DPL). In the proliferative phase (14th DPL), the IFA showed improvement in functional aspects in the combined treatment group. On the other hand, nociceptive sensitivity was reestablished in all treatment groups. In summary, our findings indicate that the combined use of açaí gel with LBT may be a therapeutic alternative in the management of tendon injury repair.
Acesso aberto (Open Access)
A indução do comportamento tipo ansiedade e estresse oxidativo pela indometacina no cérebro do Danio rerio (Zebrafish) é prevenida pelo alfa-tocoferol
(Universidade Federal do Pará, 2021-01) PINHEIRO, Jéssica Souza; OLIVEIRA, Karen Renata Herculano Matos; http://lattes.cnpq.br/3032008039259369; SILVA, Anderson Manoel Herculano Oliveira da; http://lattes.cnpq.br/8407177208423247
The non-steroidal anti-inflammatory drugs are among the most used and prescribed in the world, however this type of drug has several side effects at the neural level. Studies related to neurobehavioral and neurochemical damage of this class of drug are still necessary for a better understanding of all the possible damages that they can cause. As a result, indomethacin, which is an NSAID, has been widely used to treat pathologies such as rheumatoid arthritis, musculoskeletal injuries, osteoarthritis and postoperative pain. Indomethacin non-selectively blocks the enzymes COX-1 and COX-2, acting to decrease the production of prostaglandins. Therefore, this study proposed that the indomethacin could be generated anxiogenic effects and oxidative stress in the brain, and whether the antioxidant α-tocopherol exercised protection against the possible damage caused by indomethacin in zebrafish. The animals used were fish of the species Danio rerio (n=160), subdivided into the following groups: Control - Saline 0.9%; Indomethacin - INDO 0.5 mg/kg; INDO 0.75 mg/kg; INDO 1.0 mg/kg; INDO 2.0 mg/kg; INDO 3.0 mg/kg; α-Tocopherol - TF; TF + INDO 1 mg/kg; TF + INDO 2 mg/kg and were subjected novel tank diving test, the parameters time on top, freezing, erratic swimming and crossed quadrants were analyzed. The statistical analysis of the results was performed using one-way ANOVA with a post-test bonferroni or tukey for comparison between groups, with values with p <0.05 being considered significant. The results regarding the behavioral parameters and oxidative stress were expressed as mean ± standard error or standard deviation. The parameters that showed statistical differences were the time at the top and freezing, where the animals of the groups INDO 0.5 mg/kg, INDO 0.75 mg/kg, INDO 1 mg/kg and INDO 2 mg/kg explored for less the top of the apparatus compared to the CTRL group. In the freezing parameter the groups treated with indomethacin INDO 0.5 mg/kg, 0.75 mg/kg and 2 mg/kg did not show statistical differences with the CTRL group, however there was a difference between the CTRL and INDO groups 1 mg/kg. In the freezing parameter, the animals in the INDO 1 mg/kg group showed a longer time without movement compared to the CTRL group. In the other parameters, there were no significant differences between the groups treated with the control group. The analysis of lipid peroxidation, the INDO 1 mg/kg and INDO 2 mg/kg groups showed an increase in MDA production compared to the CTRL group, thus inferring that there was an increase in oxidative stress when animals were treated with indomethacin. The α-tocopherol exercised protection when animals were previously treated in both the TF + INDO 1 mg/kg group and the TF + INDO 2 mg/kg group compared to the INDO 1 mg/kg and INDO 2 mg/kg groups, respectively. Therefore, indomethacin is involved in inducing anxiety-like behavior and oxidative stress in zebrafish brains.
Acesso aberto (Open Access)
Análise in vitro do potencial antitumoral do conjugado LDE/Paclitaxel comparado à formulação do comercial Taxol sobre linhagem celular C6 de glioblastoma de rato
(Universidade Federal do Pará, 2022-09) ANJOS, Ana Carolina Brito dos Anjos; FRANCO, Edna Cristina Santos; http://lattes.cnpq.br/5939607544965550; https://orcid.org/0000-0003-2909-949X; LEAL, Walace Gomes; http://lattes.cnpq.br/2085871005197072
Glioblastoma, also known as grade IV astrocytoma, is one of the most common and aggressive types of tumors in the central nervous system. Among the characteristics of this type of tumor, the following stand out: infiltration of isolated tumor cells in normal brain tissue, cell proliferation, angiogenesis and intense necrosis. Currently, the main therapeutic approach consists of surgical resection followed by radiotherapy and chemotherapy. However, in most cases, the tumor is not well defined, spreading through the brain region, which makes it difficult to fully resection. In addition, the removal of tissue from this region can leave several sequels. Consequently, patients have high rates of recurrence and low rates of survival. Another problem in the treatment of this type of tumor is due to the lining of the blood-brain barrier that restricts the entry of molecules and substances, including drugs. Thus, this project aims to analyze the antineoplastic effects of the association of a nanoparticle called LDE with a structure similar to low-density lipoprotein (LDL) that will act as a carrier of the drug paclitaxel (PTX), commercially known as Taxol®, it is a chemotherapeutic drug whose cell antiproliferative action has been proven in the treatment of other types of cancer, such as breast and refractory ovarian cancers. For this purpose, the mouse glioblastoma cell line C6 was used for performing in vitro analysis regarding the effects of these treatments on aspects of viability, cytotoxicity and cell death by apoptosis, using the ApoTox-GloTM Triplex Assay kit (Promega Corporation), which performs the three previously mentioned analyses, sequentially. To evaluate growth and drug effect on PTX and LDE/PTX treatment groups, approximately 1x106 cells were cultured in 96-well microplates at concentrations of 0.01; 0.1; 1 and 10 μM in the times of 24h, 48h and 72h. The control was not exposed to the compounds, containing only DMEM culture medium. Results obtained after treatments with PTX and LDE/PTX were expressed as mean ± standard deviation and analyzed by one-way (cytotoxicity) and two-way (viability and apoptosis) ANOVA, followed by Tukey's post hoc test. Differences were considered significant when p ˂ 0.05.
Acesso aberto (Open Access)
Investigação dos efeitos bioquímicos, proteômicos e estruturais da exposição prolongada ao cloreto de mercúrio sobre a medula espinhal de ratos
(Universidade Federal do Pará, 2019-09) CORRÊA, Márcio Gonçalves; LIMA, Rafael Rodrigues; http://lattes.cnpq.br/3512648574555468; https://orcid.org/0000-0003-1486-4013
Mercury chloride (HgCl2) is a pollutant widely found in the environment. This form of mercury is able to promote several damages to the Central Nervous System (CNS), including changes to the motor cortex, an area related to the planning and execution of motor activity. However, the effects of HgCl2 on the spinal cord, an important pathway for the communication between the CNS and the periphery, are still unknown. We exposed adult rats for 45 days to HgCl2, orally, to investigate the effects on oxidative biochemistry, proteomic profile, and spinal cord structures. Our results showed that exposure to this metal promoted increased levels of Hg in the medullary parenchyma, impaired oxidative biochemistry, changes in antioxidant system proteins, energy metabolism and myelin structure; as well as caused disruption in the myelin sheath and reduction in neuronal density. Thus, we conclude that prolonged exposure to HgCl2 triggers biochemical changes and in the expression of several proteins, resulting in damage to the myelin sheath and reduction of neurons in the spinal cord, which may be related to motor damage. Keywords:
Acesso aberto (Open Access)
Estudos citogenéticos e moleculares nos gêneros Mesomys e Lonchothrix (Rodentia, Echimyidae, Eumysopinae)
(Universidade Federal do Pará, 2022-08-29) OLIVEIRA, Leony Dias de; SILVA, Willam Oliveira da; http://lattes.cnpq.br/0903402972891613; https://orcid.org/0000-0003-3125-1075; NAGAMACHI, Cleusa Yoshiko; http://lattes.cnpq.br/8887641213110093; https://orcid.org/0000-0003-1516-2734
The Echimyidae family is considered the most taxonomically diverse among South American hystricognathi rodents, comprising 25 genera and 93 species. The subfamily Eumysopinae is represented by nine genera, among which we highlight the arboreal genera Mesomys, which has four recognized species, and Lonchothrix described as monotypic (L. emiliae), both distributed in the Amazon. Morphological, molecular and chromosomal studies in the genera Mesomys and Lonchothrix have contributed to a better understanding of taxonomic design, phylogenetic relationships and karyotypic patterns. Recent molecular investigations have shown an as yet undescribed diversity, suggesting that these taxa are even more diverse than previously assumed. Furthermore, the limits of geographic distribution in the Amazon for the species M. hispidus and M. stimulax have been questioned by some authors. In this sense, the current study sought to investigate the karyotypic diversity and the geographic limits of the Mesomys and Lonchothrix genera, based on classical and molecular cytogenetic analysis and through sequences of the mitochondrial genes Cytochrome b (Cytb) and Cytochrome Oxidase - Subunit I (COI) from different locations in the Brazilian Amazon. The species M. stimulax and Mesomys sp. n. presented 2n=60/NF=110, while M. hispidus presented 2n=60/NF=112 and Lonchothrix emiliae presented 2n=66/NF=126, both unpublished karyotypes for the genera. Phylogenetic analysis confirmed Mesomys and Lonchothrix as sister genera and showed a high intraspecific rate in M. hispidus and Mesomys sp. n. from Itaituba, may be related to a new lineage in the genus Mesomys.
Acesso aberto (Open Access)
Ativação do receptor canabinóide tipo 1 (CB1r) previne o estresse oxidativo cerebral e inibe o comportamento tipo agressivo em Danio rerio (Zebrafish)
(Universidade Federal do Pará, 2022-08-17) PINHEIRO, Emerson Feio; SILVA, Anderson Manoel Herculano Oliveira da; http://lattes.cnpq.br/8407177208423247
Aggression is a set of complex actions that involve several factors of a genetic, neurophysiological, hormonal and behavioral nature. Furthermore, the brain redox state can also influence aggressive behavior in different species. Thus, modulators of this process can influence the expression of aggressive episodes, between them is the Endocannabinoid System that acts as the main neuromodulator of the CNS, in addition to exerting an antioxidant effect in different conditions. However, its participation in the modulation of aggressive-like behavior needs to be better understood. In this context, this study evaluated the role of cannabinoid receptor type 1 (CB1r) in brain redox state and aggressive-like behavior in Danio rerio (Zebrafish). For this, 64 animals were subdivided into groups: (a) Control (n=26), (b) ACEA (n=30) and (c) AM-251 (n=12), all treated with the drugs of interest: (a) Vehicle (NaCl 0.9%); (b) ACEA agonist 1 mg/kg; (c) 1 mg/kg AM-251 antagonist. The animals were isolated in pairs, without physical contact for 24 hours, followed by pre-treatment and after 30 minutes of pharmacokinetics, the fights were filmed for 30 minutes, the individuals were identified as Dominant or Subordinate and the brains were collected for evaluation of the state brain redox of these individuals. Our results demonstrate, for the first time, that the activation of CB1r by the ACEA agonist modulates aggressive-like behavior and, consequently, partially interferes with the establishment of social hierarchy in Zebrafish, through a redox-independent mechanism. We suggest, therefore, that acute treatment targeting CB1r is a useful neuropharmacological tool to elucidate the role of CES in social interaction and aggressive behavior, allowing a translation with numerous pathologies that have aggression as a behavioral disorder.