فصلنامه علوم اعصاب شفای خاتم
سال هفتم شماره 1 (پیاپی 38، زمستان 1397)

The basal ganglia are subcortical structures of the brain which are involved in the motor system. One of the common disorders related to malfunctioning of the basal ganglia is Parkinson’s disease (PD). PD is accompanied by strong and permanent beta band oscillations in the basal ganglia. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) in the basal ganglia is known as an approach to reduce pathological beta oscillations in PD and to improve PD-related motor symptoms. Despite the success of this approach, its underlying mechanisms are still unclear. In this study, we proposed a computational network model for the cortico-basal ganglia loop based on the model suggested by Terman and colleagues earlier. We modified the network model in the manner that it can generate pathological beta oscillations in the PD state. Then, by applying different DBS scenarios (such as regular and irregular high frequency excitation of STN), we investigated which scenario is able to reduce the pathological beta power more efficiently. Our results show that the network model can generate pathological beta band oscillations similar to what has experimentally been observed in the PD state. Our simulation results indicate that the regular DBS outperforms the irregular DBS, in terms of reducing the PD-related beta oscillations and improving the motor symptoms. Using our simulation results, we conclude that applying regular high frequency DBS on the STN neurons in the basal ganglia can ameliorate PD-related motor deficits better than irregular DBS pulses. This simulation result is experimentally testable.

Personality is a collection of traits that leads to individual differences in behavior as well as behavior stability and durability. This aim of the present investigation was to study psychometric features of the Big-Five personality trait’s questionnaire in children and adolescence in Mashhad. The sample included 450 students of Mashhad (253 females, 197 male) ranged between 8 and 18 years’ old that were selected from different Mashhad’s schools by multi-stage cluster method. Cronbach alpha test revealed 0.64 for extraversion, 0.73 for agreeableness, 0.70 for conscientiousness, 0.72 for neuroticism, 0.70 for openness, and 0.80 for total of the test. Moreover, test-retest correlation coefficient within a one-month interval range showed from 0.85 for openness to 0.92 for conscientiousness. The result of independent t-test showed that there are no significant differences between girls and boys personality factors. The results of factor analysis showed that special amount of factors is significant. Data from analysis after varimax rotation showed that the questionnaire was saturated with 5 factors that together explained 30.04% of the variance. The present data show that the Big-Five of personality trait’s questionnaire for children and adolescence has a high internal consistency, good validity, and reliability as well as a good fit factor analysis. In addition, there is no difference between female and male students in personality factors.

In the recent years, neuroimaging research on functional Magnetic Resonance Imaging (fMRI) is used in many pathological and mental conditions. The analysis of alterations in the resting state networks (RSN) is an important method for the scrupulous understanding of the function and connectivity changes of the disease in order to provide new diagnostic and therapeutic approaches. In this paper, we studied the resting-state functional MRI (Rs-fMRI) data in Parkinson’s disease (PD) to explore the complex disruption in the RSNs and the functional interactions between them. A total Rs-fMRI data of 10 Parkinsonism and 10 healthy people in the 3T-MRI system were considered. Probabilistic independent component analysis (PICA) was used to extract network components. RSNs were identified using spatial correlation with a rest reference template network. Dual regression and randomize technique calculated individual differences between the groups. Group component maps resulted in some main clusters of RSN that significantly overlapped with the reference network, such as the visual cortex, salience network, and supplementary motor area. Individual differences between RSN maps identified temporal, salience and cingulate networks as the main clusters. Most of the previous studies investigated the functional connectivity alterations in PD by seed-based analysis. Here, we employed the data-driven approach based on group PICA to extract and evaluate RSN changes in all related neural networks. Our finding indicates that changes of the functional architecture of the RSNs are associated with PD.

Positive psychology, along with the repair of injuries, moves towards optimizing the quality of life. The quality of life of nurses is very important high levels of work stress of nurses can affect their quality of life and consequently the quality and quantity of patient care. The purpose of this research was to investigate the role of self-efficacy and resilience in the quality of life of nurses. The present study was a descriptive-correlational study. The population was nurses working in Tehran in 2016-2017. The sample consists of 200 individuals selected by random sampling method. Subjects completed World Health Organization Quality of Life Questionnaire, Scherer Self-efficacy and Connor and Davidson Resilience Questionnaire. Self-efficacy significantly increases the quality of life of nurses in Tehran hospitals by 0.266. In addition, the contribution of the resilience variables was significant (0.385) in predicting the quality of life of nurses in this city. Self-efficacy and resiliency can together account for 33.6% of variance in nursing quality of life. Resiliency skills training and increasing the psychological capabilities, especially self-efficacy, are effective approaches for improving the nurses' quality of life.

Epilepsy is a neurodevelopmental disorder and prenatal factors exert a profound influence on the development of the nervous system in the offspring. Therefore, this study was designed to investigate the effect of seizure during pregnancy on pentylenetetrazol (PTZ)-induced seizure-like behavior in adult male mice offspring. After pregnancy, mice were classified as: i) naive group; ii) seizure group, induction of seizure between the fourteenth and nineteenth days of pregnancy by application of PTZ; iii) sham group, received normal saline intraperitoneally during the fourteenth and nineteenth days of pregnancy; and iv) control group, pregnant mice without injection during pregnancy. At postnatal day 95, serum glial cell-derived neurotrophic factor (GDNF) levels and seizure susceptibility to PTZ in male offspring of all groups were evaluated. The results showed that serum GDNF levels and seizure severity of offspring of mice in the seizure group were significantly higher than male offspring in the other group. The present findings showed that seizure during pregnancy may enhance seizure susceptibility in male offspring, possibly via increasing serum GDNF.

Nurses need effective psychological interventions to improve quality of their life and promote resiliency to professional and social challenges. The purpose of this study was to investigate the effectiveness of acceptance and commitment group therapy on quality of life and resilience of nurses. This study was an experimental research investigation, using pre-post and follow-up testing plans with a control group. The statistical population was all nurses working in hospital in 22 different areas of Tehran. Among them, one hospital (Khatam Alanbia) was selected by multi stage cluster sampling technique, and then randomly 40 nurses were selected and placed into two control and experimental groups. The experimental group participated in a twelve-session group therapy based on acceptance and commitment plan for 12 weeks, while the control group received no intervention. In order to collect data, the WHOQOL questionnaire and the Connor-Davidson resilience scale (CD-RISC) was used. The results showed that acceptance and commitment training was significantly improved their quality of life (F1,28=9.1; P=0.005) and resilience (F1,28=12.3; P=0.002). In the follow-up studies, this effect was significantly permanent on quality of life (F1,28=9.9; P=0.004) and resilience (F1,28=13.66; P=0.001) of nurses. Improving skills using acceptance and commitment training can be considered as an ideal method for increasing resilience and improving the quality of life of nurses.

Migraine is a neurovascular illness with repeated attacks of modest to intense headache, lasting 4–72 hours and linked to nausea, vomiting, and sensitivity to light and noise. Migraine is often associated with asthma, anxiety, depression, and chronic pain. Recent development in basic and clinical investigations has augmented our grasp of the pathophysiology of these headaches. New drugs and treatment for the improvement of these headaches are emergent. Therefore, biomarkers provide a dynamic and a potent indicator to understanding the spectrum of neurological disease with applications in observational and analytic epidemiology, randomized clinical trials, screening and analysis and forecast. Biomarkers can also reflect the entire spectrum of disease from the earliest manifestations to the terminal stages. This review discusses the definition and uses of migraine biomarkers, particularly their role in diagnosis, risk stratification and management of disease.

Hepatic encephalopathy (HE) is a complicated brain disorder that has resulted from the liver failure. In HE, due to the inability of the liver in detoxification, the concentration of toxins, such as ammonia, will be increased in the blood and brain. To preserve neurons from the adverse effects of ammonia, astrocytes convert it to glutamine. The increase in glutamine, in turn, alter osmotic pressure and the volume of the interstitial fluid in the brain. On the other hand, the increase in ammonia level also excites immune cells in the brain and induces neuroinflammation. The high levels of ammonia and subsequent neuroinflammation alter neurotransmitter levels, which in turn induce cognitive dysfunctions, including learning and memory impairments as well as locomotion and coordination disorders. Glutamate and GABA and the downstream signaling cascades are the main molecular pathways that are affected in HE. According to the latest molecular data, it can be concluded that different signaling molecules downstream to the neurotransmitters receptors, such as Ca2+-dependent kinases including protein kinase C and calcium/calmodulin-dependent protein kinase II, mitogen-activated protein kinases and inflammatory cytokines, are proposed as the effective molecules in pathogenesis as well as potential targets for controlling and treatments of HE in the future. Considering the multidimensional appearance of HE, it can be proposed that a complex of treatment strategies, including the use of lowering ammonia level agents, effective antibiotics, anti-inflammatory drugs, and a balance in protein intake can effectively control the symptoms of HE.

Glioblastoma multiform (GBM) or grade IV glioma is the most common and aggressive primary human brain tumor. Primary GBMs which arise spontaneously from glial cells and represent the vast majority of GBM are usually related to epidermal growth factor receptor amplification and mutations, deletion of phosphatase and tensin homolog (PTEN) on chromosome 10, p16 deletion, and TERT promoter mutation. Despite advances in treatment over the past few decades the median survival time of GBM patients is 12.1-14.6 months after diagnosis and only 3-5% of patients survive longer than 3 years. The effect of usual treatments, including surgery, radiotherapy, chemotherapy, and a combination of radiotherapy and chemotherapy, have extremely low effectiveness. Although surgery and temozolomide application during and after radiotherapy increases patient survival time, they have various side effects. Therefore, introducing a novel drug that able to inhibit GBM cell growth, proliferation, migration, and invasion is required. Since cancer cells have surface molecules that are over-expressed or altered, the molecular structures called aptamers have been designed using systematic evolution of ligands by exponential enrichment (SELEX) process to target these surface molecules. To date, several aptamers with advantages and disadvantages have been applied for the treatment of different diseases, including cancer, that are discussed in this study. Several aptamers with high capacity in the detection of GBM have been recently designed using the SELEX process that shows the high potential of aptamers in the management of GBM.

Microorganisms living in the form of symbiosis in the intestine are called gut microbiota. The gut microbiota consists of bacteria, archaea, and eukaryotes. Nonetheless, bacteria are the dominant population of the gut microbiota. The gut microbiota has a beneficial relationship with humans. About 1014 microorganisms inhabit in the intestine, which regulate many physiological functions. In addition to the microbiota effect on the digestive tract, these microorganisms can regulate the function of the brain and the central nervous system. The intestinal nervous system according to the being autonomous and similarity to the central nervous system is known as the second brain. The gut microbiota is an effective factor in the behavior and mood changes and it also prevents the development of the nervous system diseases, such as multiple sclerosis, autism, schizophrenia, Alzheimer, and Parkinson. The gut microbiota regulates the function of the central nervous system through the intestinal nervous system, the production of metabolites, the stimulation of enteroendocrine cells, and the immune system. Inappropriate nutrition, excessive use of antibiotics, stress, anxiety, and depression disturb the balance of microbiota (dysbiosis), which is an important factor in exacerbating the nervous system diseases.