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- Repeated exposure to ketamine in adolescent rats results in persistent anxiety in the adulthoodPublication . Amorim, Manuela; Bravo, Joana; Silva, Ana Isabel; Alves, Cecília Juliana; Monteiro, Pedro; Magalhãess, Ana; Summavielle, TeresaAdolescent development of the prefrontal cortex (PFC) is accompanied by important changes in glutamatergic, GABAergic and dopaminergic circuitries, susceptible to modulation by N-methyl-D-aspartate receptors (NMDAR) antagonists. Repeated ketamine was associated with social and memory deficits, but other relevant factors, such as anxiety, were not sufficiently addressed. The present study aimed to examine the behavioral and molecular consequences of repeated exposure to ketamine with a particular focus in anxiety. Methods. We treated male adolescent Wistar rats, starting postnatal day (PND) 35, with ketamine (30 mg/kg, i.p, 7 days). Behavioral evaluation was conducted in the adulthood (PND 60). The elevated plus maze (EPM) and open field tests were used to evaluate anxiety and locomotion, while sociability and novelty recognition were assessed through the novel object recognition (NOR) and the sociability and social novelty tests. At the end of the behavioral evaluation, brains were dissected and the prefrontal cortex used for biochemical evaluation. Results. Analysis of the elevated plus maze (EPM) data revealed a ketamine-induced anxiety-like profile, corroborated by the open field data. Ketaminetreated rats also failed to increase contact time with a conspecific in the social affiliation test and with an unknown rat in the novelty preference test. At the molecular level, frontal expression levels of tyrosine hydroxylase were found decreased. Conclusion. Altogether, these results show that repeated ketamine-exposure in the adolescent may result in long-term anxiety
- The multiplicities of an ethics committee in higher educationPublication . Tavares, Diana; Cruz, Agostinho; Cabral, Ana Paula; Machado, Alberto; Sousa, Helena; Curado, Henrique; Faria, Isabel; Amorim, Manuela; Gonçalves, Maria João; Lopes, Paula Maria da Costa; Monteiro, Pedro R.In the academic context, the main activity of ethics committees is evidently to regulate and monitor any investigation carried out within the institution, if the object of study is a person or biological material. However, it is important to note that ethics committee activity does not end, and cannot end, in this sphere of action. These entities are fundamental in raising awareness of the academic community for the assumption and incorporation of certain principles and values in their practices and in those of their members. Those principles and values include professional secrecy, respect for integrity and privacy, principles that become even more relevant when they refer to vulnerable people, such as health users. In a constantly changing world, ethics committees must identify new challenges and anticipate, as far as possible, action strategies. Having an ethics committee in a higher educational institution provides opportunities to, in a timely manner, be aware of the state of the art in bioethics or have access to recent research in healthcare.
- MDA in adolescent male rats - decreased serotonin in the amygdala and behavioral effects in the elevated plus-maze testPublication . Faria, Raquel; Magalhães, Ana; Monteiro, Pedro; Silva, Joana Gomes da; Tavares, Maria Amélia; Summavielle, TeresaLong-term behavioral consequences of the neurotoxicity produced by 3,4-methylenedioxymethamphetamine (MDMA) in the adolescent rat are still mostly unknown. Here, adolescent male rats (postnatal day 45 PND [45]) were exposed to 10 mg/kg of MDMA, intraperitoneally, every 2 h for 6 h. Controls were given 0.9% saline in the same protocol. Ten days after exposure, the behavioral effects of MDMA were assessed in the elevated plus-maze (n = 6 per group). After behavioral testing, animals were sacrificed and the amygdalae were dissected and processed for HPLC determination of dopamine (DA), serotonin (5-HT), and metabolites. Results showed a significant decrease in the 5-HT content (P < 0.05), but no significant alterations in DA or its metabolites. Behavioral observation in the elevated plus-maze showed a decreased number of entries in the unprotected arms (P < 0.05), which were correlated to the number of entries and time spent in the central platform. Rearing was also decreased (P < 0.05). No differences were observed in head dips, grooming, or number of entries in the protected arms of the apparatus. Therefore, we conclude that, as in the adult rat, exposure to MDMA in the adolescent rat is associated to long-term depletion of the 5-HT content and increased anxiety-like behavior.
- The influence of job rotation on wrist position sense: a preliminary study among assembly workers in a real-life occupational settingPublication . Santos, Joana; Mesquita, Inês; Monteiro, Pedro; Santos, Rubim; Baptista, João Santos; Vaz, MárioThe effectiveness of job rotation in industrial environment is still controversial, namely during tasks with high functional similarity, as assembly tasks. Thus, the aim of this study was to investigate the influence of job rotation on wrist position sense acuity among experienced assembly workers. Eight healthy assembly workers divided in two groups (four assembly workers performed task rotation and four assembly workers performed tasks with no rotation) participated in this field study. Manifestations of muscle fatigue of wrist flexors and extensors muscles were obtained by surface electromyography during a standardized test contraction, while wrist position sense errors were assessed by electrogoniometry. After a workweek, d espite not statistically significant, wrist flexors muscles in the no rotation group showed EMG signs of fatigue. The two groups showed a trend to increase position error for flexion after a workweek. Future research should include a higher number of participants and other techniques to evaluate muscle fatigue and their impact on positon sense acuity.
- Obesity effects on muscular activity during lifting and lowering tasksPublication . Colim, Ana; Arezes, Pedro; Flores, Paulo; Monteiro, Pedro; Mesquita, Inês; Braga, Ana CristinaObesity is an emerging health problem and its incidence has been increasing throughout the workforce. In industrial workstations, vertical handling tasks (VHT), including lifting and lowering, are very common and can cause a significant muscular overload for the involved workers. During these tasks, muscular activity may be considerably affected by workers' body conditions. This study aims to analyze and compare the muscular activity in subjects with different obesity levels, using surface electromyography (EMG), during predefined VHT. Six different VHT (combining 5, 10 and 15 kg loads with two task styles) were performed. EMG data normalization was based on the percentage of Maximum Contraction during each Task (MCT%). The results show that obesity influences MCT%, which in turn increases the muscular effort during VHT. The current investigation demonstrates that obesity is a relevant musculoskeletal risk factor regarding VHT. The engineering analysis and design implications of this work can thus be perceived.
- Virtual reality in the treatment of acrophobiaPublication . Maravalhas, Vanessa; Marques, António; Sousa, Sara; Monteiro, Pedro; Simões De Almeida, RaquelExposure Therapy using Virtual Reality has been indicated as one of the most promising therapeutic approaches in the treatment of Acrophobia, because Virtual Reality generates exposure conditions systematic controlled and customized desensitization of the individual concerning the phobic incitement and the impulsive responses related to it, potentiating the emotional self-regulated competence and the incorporated cognitive restructuration. This quasi-experimental study had the purpose to analyze the impact of an exposure therapy program using Virtual Reality in the reduction of fear of heights on a sample of the Portuguese population. In this study participated 19 people with and without fear of heights, being distributed by the experimental and control groups. The program was composed of 8 sessions distributed biweekly, corresponding to a total program duration of 4 weeks. The impact of the program was analyzed through the administration of anxiety and acrophobia level assessment instruments and operationalization of psychophysiological procedures, focused on the biofeedback principles, before and after the intervention. The results from both self-report and psychophysiological data revealed a significant reduction in fear of heights in the participants exposed to the exposure therapy program, showing a positive impact of this protocol on the treatment of Acrophobia.
- The effect of dental instruments on grip strengthPublication . Silva, Vanessa; Costa, Inês; Fonseca, Patrícia; Monteiro, Pedro; Santos, JoanaDentist work requires comfort and visibility, which sometimes causes an incorrect, maladjusted, and static posture, affecting mostly the upper limbs. It is due to prolonged work that oral health professionals are more susceptible to developing musculoskeletal disorders (MSDs) of the hand and wrist. The propose of this study was to evaluate and analyze the variation of grip strength in dental students. We also pretend to evaluate the incidence of signs and symptoms of MSDs. A clinical dental procedure was simulated using instruments of different design on phantoms to evaluate the palmar grip. Grip strength was measured with a dynamometer. The Nordic Musculoskeletal Questionnaire was conducted to assess the incidence of symptoms of MSDs. The most prevalent symptoms in this population were neck, lower back, and shoulder pain. During the procedure, 43 participants found the ergonomic curette more comfortable. After scraping with the metallic curette, a lower palmar grip strength was observed. Women have a higher incidence of MSDs and lower grip strength. Participants should transform and improve clinical habits to promote better working conditions and decrease MSDs. It was concluded that the grip force exerted during root scraping depends on the design of the curette. Instruments with a larger diameter and lower weight are more ergonomic and require less grip force.
- Can lycopene be considered an effective protection against cardiovascular disease?Publication . Costa-Rodrigues, João; Pinho, O.; Monteiro, PedroLycopene is a bioactive component mainly found in tomato. It is characterized by a high antioxidant potential, the highest among carotenoids. Mainly due to this property, lycopene has been suggested to display many beneficial effects, including its potential cardioprotective role. Despite some contradictory observations, which appear to be mainly caused by discrepancies in the different experimental protocols applied in the different studies, growing evidence points to clear benefits of lycopene in the maintenance of cardiovascular function and health. The knowledge about lycopene's preventive effects in atherosclerosis, and other cardiovascular diseases, must be translated into changes in food patterns, aiming to increase the consumption of tomato, tomato-containing products, or other foods with high lycopene content, which can have an important impact on cardiovascular disease, particularly in countries where this represents a major public health concern.
- Muscle loading and psychophysical effects of obesity during vertical handling tasksPublication . Colim, Ana; Arezes, Pedro; Flores, Paulo; Monteiro, Pedro; Mesquita, InêsIt has been recognized by many researchers that the prevalence of obesity is a serious public health problem. Several physical problems are associated with obesity, which can negatively affect the individuals’ work performance. In occupational contexts, vertical handling tasks, including lifting and/or lowering loads, are common and produce significant muscle loading. For these reasons, Surface electromyography (EMG) data were collected bilaterally from muscles recruited during these tasks. Additionally, the participants reported physical loading by using the Rated Perceived Exertion scale (RPE). These techniques sought to analyze the physical loading during vertical handling tasks. The obtained results indicate that obesity seem to increase the muscle loading during vertical handling tasks. However, obesity level does not seem to influence the RPE values.
- Characterization of cellular and molecular effects of lycopene on human bone cellsPublication . Costa-Rodrigues, João; Fernandes, Maria Helena; Pinho, Olívia; Monteiro, PedroBone is a dynamic tissue that undergoes continuous remodeling. This process is modulated by numerous factors, among which is oxidative stress. Mainly due to its high antioxidant potential, lycopene has been linked to a decreased risk of some chronic diseases, including osteoporosis, but the characterization of lycopene effects on bone tissue remains to be elucidated.