AIMS Neuroscience最新文献

During prenatal life, exposure to synthetic glucocorticoids (SGCs) can alter normal foetal development, resulting in disease later in life. Previously, we have shown alterations in the dendritic cytoarchitecture of Purkinje cells in adolescent rat progeny prenatally exposed to glucocorticoids. However, the molecular mechanisms underlying these alterations remain unclear. A possible molecular candidate whose deregulation may underlie these changes is the glucocorticoid receptor (GR) and neurotrophin 3/ tropomyosin receptor kinase C, neurotrophic complex (NT-3/TrkC), which specifically modulates the development of the neuronal connections in the cerebellar vermis. To date, no evidence has shown that the cerebellar expression levels of this neurotrophic complex are affected by exposure to a synthetic glucocorticoid in utero. Therefore, the first objective of this investigation was to evaluate the expression of GR, NT-3 and TrkC in the cerebellar vermis using immunohistochemistry and western blot techniques by evaluating the progeny during the postnatal stage equivalent to adolescence (postnatal Day 52). Additionally, we evaluated anxiety-like behaviours in progeny using the elevated plus maze and the marble burying test. In addition, an environmental enrichment (EE) can increase the expression of some neurotrophins and has anxiolytic power. Therefore, we wanted to assess whether an EE reversed the long-term alterations induced by prenatal betamethasone exposure. The major findings of this study were as follows: i) prenatal betamethasone (BET) administration decreases GR, NT-3 and TrkC expression in the cerebellar vermis ii) prenatal BET administration decreases GR expression in the cerebellar hemispheres and iii) enhances the anxiety-like behaviours in the same progeny, and iv) exposure to an EE reverses the reduced expression of GR, NT-3 and TrkC in the cerebellar vermis and v) decreases anxiety-like behaviours. In conclusion, an enriched environment applied 18 days post-weaning was able to restabilize GR, NT-3 and TrkC expression levels and reverse anxious behaviours observed in adolescent rats prenatally exposed to betamethasone.

Glioblastoma (GB) is the most malignant subtype of brain cancer derived from astrocytes in the brain. Radiotherapy is one of the standard treatments for GB patients, but its effectiveness is often limited by the radioresistance of aggressive GB cells. Higher dose of radiation needs to be applied to GB patients to eliminate these stubborn cells, but this also means more side effects on the adjacent healthy cells because the radiation beam could indistinguishably harm all cells exposed to it. In order to address this problem, various strategies have been studied to enhance the radiosensitivity among the radioresistant cell populations for targeted eradication of GB without harming other surrounding healthy cells. One of the promising strategies for radiosensitization is to use gold nanoparticles (AuNPs) which can enhance photoelectric effects within the radioresistant cells for higher killing efficiency even at low doses of radiation. Nonetheless, there is no evidence showing the capability of these nanoparticles to travel to brain tumor cells, therefore, the application of this nanotechnology is very much dependent on the development of a suitable carrier to deliver the AuNPs to the GB tumor sites specifically. In this review article, we discussed the potentials of neural stem cells (NSCs) as biological carriers to carry AuNPs to targeted GB tumor sites and provided new insights into the potential of NSC-based targeted delivery system for GB treatment. The information reported here may pave a new direction for clinical transformation of next-generation nanoparticle-assisted radiotherapy to optimize the efficacy of radiotherapy for GB treatment.

This study investigated the relation between sports participation, body size, and postural control in children between 3 and 11 years of age. To explore this question, children's body sway was measured across multisensory conditions manipulating visual input (the presence versus absence of visual information) and proprioceptive input (varying stance widths), with postural sway in these conditions then related to reports of children's sports participation, and anthropometric measures. Corroborating well-known findings, postural sway was systematically influenced by multisensory factors, with the removal of visual information and narrower stance widths decreasing postural stability. Of more novelty, postural sway in the most stable stance, but without vision, was significantly predicted by measures of sports participation and body size variables, with these factors contributing independently to this prediction. Moreover, the impact on postural sway of having visual input, relative to removing visual input in unstable stances, was significantly predicted by sports participation in activities stressing changing stances and bases of support (e.g., dance, martial arts). Generally, these findings support multisensory and dynamic systems theories of perceptual-motor behavior, and also support sports specificity effects in assessments of the relation between posture and sports.

Introduction: Children with epilepsy are at greater risk of developing psychiatric and behavioural disorders such as attention deficit/hyperactivity disorder (ADHD), conduct disorder, autism spectrum disorder (ASD), as well as affective and aggressive disorders than normal children which may affect the well- being and quality of life of the child.

Aim and objectives: This study aims at identifying behavioural problems in children with epilepsy enabling early diagnosis and intervention. The objectives were to assess the presence and type of behavioural problems in children with epilepsy.

Methods: A prospective cross-sectional study was conducted on children who were diagnosed as epilepsy in two age groups of 1.5-5 years and 6-18 years recruited by non-probability convenience sampling. Data regarding seizure semiology, clinical features and treatment were obtained. Children underwent IQ assessment, electroencephalogram and brain neuroimaging. Child Behaviour Check List (CBCL) was administered to parents or primary caregivers after obtaining informed consent. Results were analyzed for presence of behavioural problems using SPSS-23.

Results: In the study, out of 50 study subjects, 72% were between 6-18 years. 60% children had generalised seizures, 58% children had epilepsy for <2 years and abnormal EEG was present in 80% children. 6% children had behavioural problems and 4% had borderline presentations. Co-relation of behavioural problems with age was statistically significant with p value 0.027. Behavioural problems identified were aggressiveness and anxiety.

Conclusion: Childhood epilepsy is associated with behavioural problems along with other co-morbidities warranting a search during follow-up visits.

Take-home message: Early identification and treatment of behavioural problems in children with epilepsy by periodic assessment during follow up visits, careful selection of combination of drugs and appropriate dose can improve the overall outcome in children taking antiepileptic drugs (AEDs) for epilepsy.

Several studies have demonstrated that depression include disruptions not only for mental human disorders but also their healthy living. Rodent-based behavioral tests and models are widely used to understand the mechanisms by which stress triggers anxiety-related behaviors. This present study examined the evidence of a chronic restraint stress (CRS) paradigm in male Wistar rats for the progressive nature of depression alongside with related changes in behavior and functions. The body weight was determined, and the behavior tests, including sucrose preference and the open field test were performed. Theses parameters confirme the presence of anxiety-like and depression-like behaviors beside that we will focus on the response of ACTH and testosterone concentrations in rats. The results obtained during the experiment show that CRS led to decrease the time spent in the field center, a decrease of total distance travelled, in the stressed group compared with the control group. A significant increased of ACTH levels and decreased in testosterone hormone levels in the CRS. According to these results the CRS rodent model has value to validating the development for depression.

We have previously evidenced that Mindfulness Meditation (MM) in experienced meditators (EMs) is associated with long-lasting topological changes in resting state condition. However, what occurs during the meditative phase is still debated. Utilizing magnetoencephalography (MEG), the present study is aimed at comparing the topological features of the brain network in a group of EMs (n = 26) during the meditative phase with those of individuals who had no previous experience of any type of meditation (NM group, n = 29). A wide range of topological changes in the EM group as compared to the NM group has been shown. Specifically, in EMs, we have observed increased betweenness centrality in delta, alpha, and beta bands in both cortical (left medial orbital cortex, left postcentral area, and right visual primary cortex) and subcortical (left caudate nucleus and thalamus) areas. Furthermore, the degree of beta band in parietal and occipital areas of EMs was increased too. Our exploratory study suggests that the MM can change the functional brain network and provides an explanatory hypothesis on the brain circuits characterizing the meditative process.

The stress response is attached to psychosomatic and psychiatric disorders. Therefore, it is important to comprehend the underlying mechanisms influencing this relationship. Moreover, men and women respond differently to stress-both psychologically and biologically. These differences should be studied to have an enhanced understanding of the gender difference. However, researches shedding light on sex dimorphism implication have historically been insufficient. Based on observations that advocate the inclusion of sex as a biological variable in stress response, the present study was designed to explore sex differences in (i) depressive-like, (ii) anxiety-like behaviors, (iii) cognitive-like performances, and (iv) voluntary ethanol intake (VEI) in Wistar rat submitted to dexamethasone (DEX)-stress simulation. Rats were administered daily with DEX (1.5 mg/kg, s.c., 21 days) or vehicle. Behavior, cognitive, and VEI states of rats were evaluated in the following paradigms: forced swimming test (FST); saccharin preference test (SPT); open field test (OFT); elevated plus-maze test (EPMT); novelty suppressed feeding test (NSFT); spatial learning and memory in Morris water maze test (MWMT); VEI in two-bottle choice paradigm. DEX-treated rats showed a set of depression-like behaviors: increased time of immobility; reduced preference for saccharin consumption; increased anxiety-like behavior; cognitive impairments; and enhanced VEI. Sexual dimorphism was recorded in this study. Females were more impaired in FST, SPT, EPMT, NSFT, and VEI. Results demonstrate that DEX-treatment induced a behavioral alterations related to anxiety-depressive-like state with learning and memory impairments; confirm the facilitatory role of glucocorticoids on VEI and reveal sexual dimorphism in stress response.

Preterm-born children are at risk of slower psychomotor development. This risk may be associated with low birth weight and other perinatal factors and morbidities. We aimed to assess psychomotor development in school-aged preterm children, and to determine whether some early motor and perinatal variables could be related to and/or predict the later motor achievements. Parents of 54 very low-birth-weight preterm, 24 extremely low-birth-weight preterm and 96 control children completed the Movement Assessment Battery for Children (MABC-2-C) checklist and were interviewed about the motor milestones of their children. Significant differences were found between the preterm and control groups in the MABC-2-C results. MABC-2-C outcomes were significantly predicted by the age of crawling, the use of steroids, mechanical ventilation and intraventricular hemorrhage (IVH). The use of screening tools may allow the rapid identification of psychomotor development delays. The presence of some perinatal risk factors and some motor milestone attainments could be related to motor development in the later childhood of preterm children.

It is widely accepted that physical exercise can be used as a tool for the prevention and treatment of various diseases or disorders. In addition, in the recent years, exercise has also been successfully used to enhance people's cognition. There is a large amount of research that has supported the benefits of physical exercise on human cognition, both in children and adults. Among these studies, some have focused on the acute or transitory effects of exercise on cognition, while others have focused on the effects of regular physical exercise. However, the relation between exercise and cognition is complex and we still have limited knowledge about the moderators and mechanisms underlying this relation. Most of human studies have focused on the behavioral aspects of exercise-effects on cognition, while animal studies have deepened in its possible neuro-physiological mechanisms. Even so, thanks to advances in neuroimaging techniques, there is a growing body of evidence that provides valuable information regarding these mechanisms in the human population. This review aims to analyze the effects of regular and acute aerobic exercise on cognition. The exercise-cognition relationship will be reviewed both from the behavioral perspective and from the neurophysiological mechanisms. The effects of exercise on animals, adult humans, and infant humans will be analyzed separately. Finally, physical exercise intervention programs aiming to increase cognitive performance in scholar and workplace environments will be reviewed.