RESUMO
Light-at-night (LAN) is a worldwide problem co-distributed with breast cancer prevalence. We hypothesized that exposure to LAN is coincided with a decreased melatonin (MLT) secretion level, followed by epigenetic modifications and resulted in higher breast cancer tumors growth-rate. Accordingly, we studied the effect of LAN exposure and exogenous MLT on breast cancer tumors growth-rate. 4T1 cells were inoculated into BALB/c short day-acclimated mice, resulting in tumors growth. Growth rates were followed under various light exposures and global DNA methylations were measured. Results demonstrated the positive effect of LAN on tumors growth-rate, reversed by MLT through global DNA methylation.
Assuntos
Ritmo Circadiano , Metilação de DNA , Luz , Neoplasias Mamárias Experimentais/patologia , Melatonina/biossíntese , Fotoperíodo , Animais , Epigênese Genética , Feminino , Neoplasias Mamárias Experimentais/etiologia , Melatonina/análogos & derivados , Melatonina/urina , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Glândula Pineal/metabolismo , Transdução de SinaisRESUMO
OBJECTIVES: To explore unprompted adherence to a personalized, home-based, computerized cognitive training program in patients with multiple sclerosis (MS), and to examine the impact of training on cognitive performance. METHODS: Participants were assigned to a training (n=59) or a control group (n=48). Those in the training group were instructed to train three times a week for 12 weeks. The control group received no training. All participants were evaluated with a Neuropsychological Examination (N-CPC) at baseline and at the end of the study. RESULTS: In the training group, 42 (71.2%) participants adhered to the training schedule and 22 (37.3%) completed the entire training regimen. In the control group, 24 (50.0%) participants agreed to be retested on the N-CPC. The training group showed a significant improvement over that shown by the control group in three memory-based cognitive abilities (general memory, visual working memory and verbal working memory). Post-hoc exploration of data from the N-CPC showed that cognitive training was also associated with increased naming speed, speed of information recall, focused attention and visuo-motor vigilance. CONCLUSIONS: The appreciable rates of adherence and cognitive improvements observed indicate that personalized cognitive training is a practical and valuable tool to improve cognitive skills and encourage neuronal plasticity in patients with MS.
