Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Neurol Clin ; 40(4): 717-727, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36270686

RESUMO

Telemedicine is a method of health care delivery well suited for epilepsy care, where there is an insufficient supply of trained specialists. The telemedicine "Hub and Spoke" approach allows patients to visit their local health clinic ('Spokes') to establish appropriate care and monitoring for their seizure disorder or epilepsy, and remotely connect with epileptologists or neurologists at centralized centers of expertise ('Hubs'). The COVID-19 pandemic resulted in an expansion of telemedicine capabilities and use, with favorable patient and provider experience and outcomes, allowing for its wide scale adoption beyond COVID-19.


Assuntos
COVID-19 , Epilepsia , Telemedicina , Humanos , Pandemias , SARS-CoV-2 , Epilepsia/diagnóstico , Epilepsia/terapia
2.
Elife ; 112022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36149059

RESUMO

Resilience, the ability to overcome stressful conditions, is found in most mammals and varies significantly among individuals. A lack of resilience can lead to the development of neuropsychiatric and sleep disorders, often within the same individual. Despite extensive research into the brain mechanisms causing maladaptive behavioral-responses to stress, it is not clear why some individuals exhibit resilience. To examine if sleep has a determinative role in maladaptive behavioral-response to social stress, we investigated individual variations in resilience using a social-defeat model for male mice. Our results reveal a direct, causal relationship between sleep amount and resilience-demonstrating that sleep increases after social-defeat stress only occur in resilient mice. Further, we found that within the prefrontal cortex, a regulator of maladaptive responses to stress, pre-existing differences in sleep regulation predict resilience. Overall, these results demonstrate that increased NREM sleep, mediated cortically, is an active response to social-defeat stress that plays a determinative role in promoting resilience. They also show that differences in resilience are strongly correlated with inter-individual variability in sleep regulation.


To many of us, it may seem obvious that sleep is restorative: we feel better after a good night's rest. However, exactly how sleep benefits the brain and body remains poorly understood. One clue may lie in neuropsychiatric disorders: these conditions ­ such as depression and anxiety ­ are often accompanied by disrupted sleep. Additionally, these neuropsychiatric disorders are frequently caused or worsened by stress, which can also interfere with sleep. This close association between stress and sleep has led some to hypothesize that sleep serves to overcome the adverse effects of stress on the brain, but this hypothesis remains largely untested. One type of stress that is common to all mammals is social stress, defined as stress caused by social interactions. This means that mice and other rodents can be subjected to social stress in the laboratory to test hypotheses about the effects of stress on the brain. Importantly, in both animals and humans, there are individual differences in resilience, or the ability to overcome the adverse effects of stress. Based on this information, Bush et al. set out to establish whether sleep can regulate resilience to social stress in mice. When the mice were gently kept awake during their normal sleep time, resilience decreased and so the mice were less able to overcome the negative effects of stress. Conversely, increasing sleep, by activating an area of the brain responsible for initiating sleep, increased the mice's resilience to social stress. Thus, Bush et al. showed that changes in sleep do lead to changes in resilience. To find out whether resilience can be predicted by changes in sleeping patterns, Bush et al. studied how both resilient mice and those susceptible to stress slept before and after social stress. Resilient mice would often sleep more after social stress; meanwhile, few changes were observed in susceptible mice. Surprisingly, sleep quality also predicted resilience, with resilient mice sleeping better than susceptible mice even before exposure to social stress. To determine whether the differences in sleep that predict resilience can be detected as brain activity, Bush et al. placed electrodes in two regions of the prefrontal cortex ­ a part of the brain important for decision-making and social behaviors ­ to measure how mice recovered lost sleep. This experiment revealed that the changes in sleep that predict resilience are prominent in the prefrontal cortex. Overall, Bush et al. reveal that sleeping more and sleeping better promote resilience to social stress. Furthermore, the results suggests that lack of sleep may lead to increased risk of stress-related psychiatric conditions. Humans are one of the few species that choose to deprive themselves of sleep: Bush, et al. provide evidence that this choice may have significant consequences on mental health. Furthermore, this work creates a new model that lays the groundwork for future studies investigating how sleep can overcome stress on the brain.


Assuntos
Movimentos Oculares , Estresse Psicológico , Animais , Camundongos , Masculino , Camundongos Endogâmicos C57BL , Estresse Psicológico/psicologia , Córtex Pré-Frontal , Sono , Mamíferos
3.
PLoS Genet ; 18(7): e1010305, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35789210

RESUMO

Circadian clocks enable organisms to predict and align their behaviors and physiologies to constant daily day-night environmental cycle. Because the ubiquitin ligase Siah2 has been identified as a potential regulator of circadian clock function in cultured cells, we have used SIAH2-deficient mice to examine its function in vivo. Our experiments demonstrate a striking and unexpected sexually dimorphic effect of SIAH2-deficiency on the regulation of rhythmically expressed genes in the liver. The absence of SIAH2 in females, but not in males, altered the expression of core circadian clock genes and drastically remodeled the rhythmic transcriptome in the liver by increasing the number of day-time expressed genes, and flipping the rhythmic expression from nighttime expressed genes to the daytime. These effects are not readily explained by effects on known sexually dimorphic pathways in females. Moreover, loss of SIAH2 in females, not males, preferentially altered the expression of transcription factors and genes involved in regulating lipid and lipoprotein metabolism. Consequently, SIAH2-deficient females, but not males, displayed disrupted daily lipid and lipoprotein patterns, increased adiposity and impaired metabolic homeostasis. Overall, these data suggest that SIAH2 may be a key component of a female-specific circadian transcriptional output circuit that directs the circadian timing of gene expression to regulate physiological rhythms, at least in the liver. In turn, our findings imply that sex-specific transcriptional mechanisms may closely interact with the circadian clock to tailor overt rhythms for sex-specific needs.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Animais , Relógios Circadianos/genética , Ritmo Circadiano/genética , Feminino , Lipídeos , Lipoproteínas , Masculino , Camundongos , Ubiquitina , Ubiquitina-Proteína Ligases/genética
4.
PLoS One ; 12(11): e0187071, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29125838

RESUMO

Nitrergic neurons of the dorsal raphe nucleus (DRN) may play a role in physiological stress responses. The caudal lateral wings (CLW) are unique compared to other rostral-caudal DRN sub-regions because they contain distinct nitric oxide (NO) synthase (NOS) populations that are independent of tryptophan hydroxylase (TPH). NOS neurons in the CLW are also highly activated during acute restraint stress. However, the effects of acute stress duration on NOS activation in the CLW are unclear. Here NADPH-d, an index of NOS activity, is used to show that sub-regions of the DRN have differential NOS activation in response to 6 hours of restraint stress in rats. We report increased NOS activity through 6 hours of restraint in the caudal lateral wings and ventromedial sub-regions. These data suggest that, NOS neurons may play a dynamic role in the response to stress duration.


Assuntos
Núcleo Dorsal da Rafe/metabolismo , Neurônios Nitrérgicos/metabolismo , Estresse Fisiológico , Animais , Ativação Enzimática , Imobilização , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Long-Evans
5.
Elife ; 62017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28726633

RESUMO

Sleep loss can severely impair the ability to perform, yet the ability to recover from sleep loss is not well understood. Sleep regulatory processes are assumed to lie exclusively within the brain mainly due to the strong behavioral manifestations of sleep. Whole-body knockout of the circadian clock gene Bmal1 in mice affects several aspects of sleep, however, the cells/tissues responsible are unknown. We found that restoring Bmal1 expression in the brains of Bmal1-knockout mice did not rescue Bmal1-dependent sleep phenotypes. Surprisingly, most sleep-amount, but not sleep-timing, phenotypes could be reproduced or rescued by knocking out or restoring BMAL1 exclusively in skeletal muscle, respectively. We also found that overexpression of skeletal-muscle Bmal1 reduced the recovery response to sleep loss. Together, these findings demonstrate that Bmal1 expression in skeletal muscle is both necessary and sufficient to regulate total sleep amount and reveal that critical components of normal sleep regulation occur in muscle.


Assuntos
Fatores de Transcrição ARNTL/genética , Encéfalo/metabolismo , Ritmo Circadiano/genética , Regulação da Expressão Gênica , Músculo Esquelético/metabolismo , Sono/genética , Fatores de Transcrição ARNTL/deficiência , Animais , Relógios Circadianos/genética , Eletrodos Implantados , Eletroencefalografia , Eletromiografia , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Regiões Promotoras Genéticas , Secretogranina II/genética , Secretogranina II/metabolismo , Vigília/genética
6.
J Neurosci ; 35(40): 13587-98, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26446213

RESUMO

Individuals with Angelman syndrome (AS) suffer sleep disturbances that severely impair quality of life. Whether these disturbances arise from sleep or circadian clock dysfunction is currently unknown. Here, we explored the mechanistic basis for these sleep disorders in a mouse model of Angelman syndrome (Ube3a(m-/p+) mice). Genetic deletion of the maternal Ube3a allele practically eliminates UBE3A protein from the brain of Ube3a(m-/p+) mice, because the paternal allele is epigenetically silenced in most neurons. However, we found that UBE3A protein was present in many neurons of the suprachiasmatic nucleus--the site of the mammalian circadian clock--indicating that Ube3a can be expressed from both parental alleles in this brain region in adult mice. We found that while Ube3a(m-/p+) mice maintained relatively normal circadian rhythms of behavior and light-resetting, these mice exhibited consolidated locomotor activity and skipped the timed rest period (siesta) present in wild-type (Ube3a(m+/p+)) mice. Electroencephalographic analysis revealed that alterations in sleep regulation were responsible for these overt changes in activity. Specifically, Ube3a(m-/p+) mice have a markedly reduced capacity to accumulate sleep pressure, both during their active period and in response to forced sleep deprivation. Thus, our data indicate that the siesta is governed by sleep pressure, and that Ube3a is an important regulator of sleep homeostasis. These preclinical findings suggest that therapeutic interventions that target mechanisms of sleep homeostasis may improve sleep quality in individuals with AS. SIGNIFICANCE STATEMENT: Angelman syndrome (AS) is a severe neurodevelopmental disorder caused by loss of expression of the maternal copy of the UBE3A gene. Individuals with AS have severe sleep dysfunction that affects their cognition and presents challenges to their caregivers. Unfortunately, current treatment strategies have limited efficacy due to a poor understanding of the mechanisms underlying sleep disruptions in AS. Here we demonstrate that abnormal sleep patterns arise from a deficit in accumulation of sleep drive, uncovering the Ube3a gene as a novel genetic regulator of sleep homeostasis. Our findings encourage a re-evaluation of current treatment strategies for sleep dysfunction in AS, and suggest that interventions that promote increased sleep drive may alleviate sleep disturbances in individuals with AS.


Assuntos
Ondas Encefálicas/fisiologia , Ritmo Circadiano/genética , Homeostase/genética , Transtornos do Sono-Vigília/genética , Ubiquitina-Proteína Ligases/metabolismo , Análise de Variância , Animais , Ondas Encefálicas/genética , Modelos Animais de Doenças , Eletroencefalografia , Eletromiografia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Mensageiro/metabolismo , Núcleo Supraquiasmático/metabolismo , Ubiquitina-Proteína Ligases/genética
7.
Physiol Behav ; 152(Pt A): 56-61, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26367452

RESUMO

Social defeat occurs when an animal is attacked and subjugated by an aggressive conspecific. Following social defeat, male Syrian hamsters fail to display species-typical territorial aggression and instead exhibit submissive or defensive behaviors even when in the presence of a non-aggressive intruder. We have termed this phenomenon conditioned defeat (CD). The mechanisms underlying CD are not fully understood, but data from our lab suggest that at least some of the mechanisms are similar to those that mediate classical fear conditioning. The goal of the present experiment was to test the hypothesis that noradrenergic signaling promotes the consolidation of CD, as in classical fear conditioning, by determining whether CD is disrupted by post-training blockade of noradrenergic activity. In Experiment 1, we determined whether systemic infusions of the noradrenergic receptor antagonist propranolol (0, 1.0, 10, or 20mg/kg) given immediately after a 15 min defeat by a resident aggressor would impair CD tested 48 h later. Hamsters that were given immediate post-training infusions of propranolol (1.0, but not 10 or 20mg/kg) showed significantly less submissive behavior than did those given vehicle infusions supporting the hypothesis that there is noradrenergic modulation of the consolidation of a social defeat experience. In Experiment 2, we demonstrated that propranolol (1.0mg/kg) given immediately, but not 4 or 24h, after defeat impaired CD tested 48 h after defeat indicating that the window within which the memory for social defeat is susceptible to beta-adrenergic modulation is temporary. In Experiment 3, we examined whether central blockade of noradrenergic receptors could recapitulate the effect of systemic injections by giving an intracerebroventricular infusion of propranolol immediately after defeat and examining the effect on CD 24h later. Centrally administered propranolol (20 µg/3 µl but not 2 µg/3 µl) was also effective in dose-dependently reducing consolidation of CD. Collectively, the present results indicate that noradrenergic activity promotes the consolidation of CD and suggest that CD is a valuable model to study the processes by which emotion and stress modulate memory in an ethologically relevant context. These data also suggest that the popular conception in the clinical literature that the anxiolytic effect of propranolol is primarily due to the drug's peripheral effects may need to be reconsidered.


Assuntos
Condicionamento Psicológico/efeitos dos fármacos , Dominação-Subordinação , Consolidação da Memória/efeitos dos fármacos , Mesocricetus/psicologia , Propranolol/administração & dosagem , Psicotrópicos/administração & dosagem , Antagonistas Adrenérgicos beta/administração & dosagem , Animais , Condicionamento Psicológico/fisiologia , Relação Dose-Resposta a Droga , Desamparo Aprendido , Masculino , Consolidação da Memória/fisiologia , Mesocricetus/fisiologia , Distribuição Aleatória , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...