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BACKGROUND: The performance of a task depends on ongoing brain activity, which can be influenced by attention, excitement, or motivation. Scientific studies have confirmed that mindfulness leads to better performance, health, and well-being. However, these cognitive efficiency modulating factors are nonspecific, can be difficult to control, and are not suitable to specifically facilitate neural processing. OBJECTIVE: The aim of this study is to evaluate the effects of transcranial direct current stimulation associated with neurofeedback on declarative memory and cerebral blood flow in university students. METHODS: In this study, we will use transcranial direct current stimulation, a low-cost physical resource that is easy to apply, has few adverse effects, and is associated with a neurofeedback resource. This, in turn, has been shown to be a training program capable of improving working memory function. RESULTS: Participants will be recruited between July 2022 and December 2022. This study is expected to conclude in July 2023. CONCLUSIONS: This study will provide preliminary results on the benefits of using the direct current neurostimulation and neurofeedback tools on the participants being analyzed. TRIAL REGISTRATION: Brazilian Clinical Trials Registry RBR-7zs8b5; https://ensaiosclinicos.gov.br/rg/RBR-7zs8b5. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/36294.

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This study was designed to evaluate the anti-inflammatory effects of a curcumin treatment on the knee of rats with induced osteoarthritis. Fifteen adult rats were used and divided in three groups: the osteoarthritis group (OAG), control group (CG-without induction of osteoarthritis), and curcumin-treated osteoarthritis group (COAG). Osteoarthritis was induced in the right knee of rats in the OAG and COAG by administering an intra-articular injection of 1 mg of zymosan. Fourteen days after induction, 50 mg/kg curcumin was administered by gavage daily for 60 days to the COAG. After the treatment period, rats from all groups were euthanized. Medial femoral condyles were collected for light microscopy and immunohistochemical staining. The expression of SOX-5, IHH, MMP-8, MMP-13, and collagen 2 (Col2) was analyzed. The COAG exhibited an increase in the number of chondrocytes in the surface and middle layers compared with that of the OAG and CG, respectively. The COAG also showed a decrease in the thicknesses of the middle and deep layers compared with those of the OAG, and an increase in Col2 expression was observed in all articular layers (surface, middle, and deep) in the COAG compared with that in the OAG. SOX-5 expression was increased in the surface and deep layers of the COAG compared with those in the OAG and CG. Based on the results of this study, the curcumin treatment appeared to exert a protective effect on cartilage, as it did not result in an increase in cartilage thickness or in MMP-8 and MMP-13 expression but led to increased IHH, Col2, and SOX-5 expression and the number of chondrocytes.

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The objective of the present study was to follow the structural modifications of the aortic wall in middle-aged rats submitted to a resistance training protocol for a period of four months. Three groups of 8 animals per group were considered: middle-aged group (MA), old control group (OC) and old trained group (OT). Training consisted in to climb a 1.1-m vertical (80° incline) ladder with weights tied to their tail. Aortic wall structural modifications were studied through light and electron microscopy and morphometry. The mean arterial blood pressure at rest was similar in the three experimental groups (p = .07). At the beginning of the experiment, the OC and OT groups had similar repetition maximums, ranging from 1.6-fold to 1.9-fold the body weight. At the end of the experiment, the repetition maximum of the OT group was 5-fold greater than the body weight (p = .03). The LV weight was 15% larger in the OT group than in the MA group and 12% larger than in the OC group (p = .02). The LV wall thickness of the OT group was significantly larger than that of both, the MA group and the OC group (p = .03). The LV internal diameter in the OT group was significantly smaller than that observed in the MA and OC groups (p = .02). Resistance training diminished the alterations associated with aging improving aortic wall structure by reducing the thickness, normalising the elastic material, the collagen and the smooth muscle cells. Resistance training seems to be a potential treatment for reducing the deleterious effects of aging on the aortic wall.

Este estudo teve por objetivo avaliar as modificações da parede da aorta de ratos Wistar de meia-idade, submetidos a treinamento resistido por 4 meses. Foram utilizados 3 grupos de animais com oito animais por grupo: meia idade (MI), idoso controle (IC) e idoso treinado (IT). Os ratos subiam uma escada vertical inclinada (80°) com pesos atrelados à cauda. A parede da aorta foi avaliada através de microscopia de luz e eletrônica e morfometria. A pressão arterial média no repouso foi similar nos três grupos experimentais (p = 0,07). No início, os grupos IC e IT tiveram treinamento de repetições máximas semelhantes, variando de 1,6 a 1,9 vezes o valor do peso corporal. No final o treinamento de repetição maxima do grupo IT foi 5 vezes maior que o peso corporal (p = 0,03). O peso do ventrículo esquerdo do grupo IT foi 15% maior do que o do grupo MI e 12% maior do que o do grupo IC (p = 0,02). A espessura da parede do ventrículo no grupo IT foi significantemente maior do que nos grupos MI e IC (p = 0,03). O diâmetro interno da cavidade do ventrículo foi significantemente menor no grupo IT do que nos demais grupos (p = 0,02). O treinamento diminuiu as alterações associadas com o envelhecimento melhorando a estrutura da parede da aorta através da redução da sua espessura, normalização quantitativa do material elástico, colágeno e das fibras musculares lisas. O treinamento resistido parece ser um tratamento potencial para reduzir os efeitos deletérios do envelhecimento na parede da artéria aorta.

El objetivo fue evaluar, por morfometria, los cambios estructurales de la aorta de ratones (Wistar) en la mitad de la vida, cuando se someten a entrenamiento de resistencia. Se utilizaron 3 grupos de animales con ocho animales por grupo: de edad media (EM), de viejos control (VC) y de viejos entrenados (VEn). Los animales subieron una escalera vertical inclinada (80°) con pesos atados a la cola. Al comienzo del experimento, los grupos de VC y VEn tenían entrenamientos de repetición máximos similares, que van desde 1,6 hasta 1,9 veces el peso corporal. Al final del experimento, el entrenamiento de repetición máxima en el grupo VEn era 5 veces mayor que el peso del cuerpo (p = 0,03). El peso del ventrículo izquierdo del grupo de VEn fue de 15% mayor que en el grupo EM y 12% mayor que en el grupo VC (p = 0,02). El espesor de la pared ventricular en el grupo de VEn fue mayor que en los grupos, EM y VC (p = 0,03). El diámetro de la cavidad del ventrículo fue significativamente menor en el grupo VEn (p = 0.03) en relación a los otros grupos. El entrenamiento de resistencia disminuyó los cambios asociados con el envejecimiento, mediante la mejora de la estructura de la pared de la aorta, mediante la reducción de su espesor, normalización cuantitativa del material elástico, colágeno y de las fibras musculares lisas. El entrenamiento de resistencia parece ser un tratamiento potencial para reducir los efectos perjudiciales del envejecimiento en la pared de la aorta.

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Studies have determined the effects of joint immobilization on the articular cartilage of sedentary animals, but we are not aware of any studies reporting the effects of joint immobilization in previously trained animals. The objective of the present study was to determine whether exercise could prevent degeneration of the articular cartilage that accompanies joint immobilization. We used light microscopy to study the thickness, cell density, nuclear size, and collagen density of articular cartilage of the femoral condyle of Wistar rats subjected to aerobic physical activity on an adapted treadmill five times per week. Four groups of Wistar rats were used: a control group (C), an immobilized group (I), an exercised group (E), and an exercised and then immobilized group (EI). The right knee joints from rats in groups I and EI were immobilized at 90 °C of flexion using a plastic cast for 8 weeks. Cartilage thickness decreased significantly in group I (mean, 120.14 ± 15.6 µm, P < 0.05), but not in group EI (mean, 174 ± 2.25), and increased significantly in group E (mean, 289.49 ± 9.15) compared with group C (mean, 239.20 ± 6.25). The same results were obtained for cell density, nuclear size, and collagen density (in all cases, P < 0.05). We concluded that exercise can prevent degenerative changes in femoral articular cartilage caused by immobilization of the knee joint.

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