فهرست مطالب

Archives of Neuroscience
Volume:2 Issue: 4, Oct 2015

  • تاریخ انتشار: 1394/06/21
  • تعداد عناوین: 10
|
  • Mehdi Zeinalizadeh *, Keyvan Tayebi Meybodi, Farid Maleki, Meysam Mohseni, Seyed Mojtaba Miri, Farideh Nejat, Mohammad Taghi Talebian, Hooman Hossein Nejad, Zeinab Mohajer Page 1
    Background
    Neurological emergencies are common causes of emergency department visits. The need for emergency medicine (EM) physicians and/or specialists worldwide is growing to meet this requirement. Delivery of time-sensitive interventions and lifesaving care requires training..
    Objectives
    The aim of this study was to evaluate the level of knowledge of EM residents in neurosurgical emergencies before and after holding an education course..
    Materials And Methods
    In this cross-sectional study, 28 EM residents during their first and second years of training were evaluated. A multiple choice questionnaire containing 60 questions about neurosurgical emergencies (radiology, cranial, spinal and spinal cord, and pediatrics) was designed by 3 neurosurgeons. Without any prior notification, pre-training exam was taken. A short-term course of education via didactic lectures in 8 sessions was held after the first exam. At the end of the course, participants were tested again in the similar conditions as the pre-training test. Scores were analyzed using paired t-tests..
    Results
    Performance of residents was significantly improved from pre-training test with mean scores from 35.7 to 42.03 on post-training test (P < 0.001). Scores between males and females in the two exams were not significantly different (P = 0.063). The second-year residents had a significantly better performance compared to the one-year residents (P < 0.001)..
    Conclusions
    At present, there is no standard education program that provides the optimum needs for EM residency training. To deal with the need of improving EM residency education in neurosurgical emergencies, teaching by neurosurgeons either through formal lectures and clinical rotations or other similar educational methods could be advantageous..
    Keywords: Emergency Medicine, Didactic Lecture, Internship, Residency
  • Christina A. Blum, Shadi Yaghi * Page 2
    Context: Cervical artery dissection (CAD) is a common cause of stroke in young adults. There is controversy over whether anticoagulation is superior to antiplatelet therapy in preventing stroke in patients with CAD, although meta-analyses to date have not shown any difference between the two treatments..Evidence Acquisition: We performed a PubMed search using each of the keywords: “Cervical artery dissection”, “Dissection”, “Carotid dissection”, and “Vertebral dissection” between January 1st, 1990 and July 1st 2015. We identified evidence-based peer-reviewed articles, including randomized trials, case series and reports, and retrospective reviews that encompass the epidemiology, clinical manifestations, pathophysiology, treatment, and outcome of cervical artery dissection..
    Results
    This paper highlights the mechanisms of cervical artery dissection and stroke in patients with dissection as well as the natural history and treatment..
    Conclusions
    Given the relatively rare incidence of this disease, multicenter studies with collaborative effort among stroke centers worldwide should be considered to enroll patients with cervical artery dissection in a randomized trial comparing the two treatments..
    Keywords: Physiopathology, Stroke, Anticoagulation, Cervical Artery Dissection, Outcome
  • Cassie Nesbitt *, Luke Wilshire, Doreen Quan, Cameron Shaw, Peter Batchelor Page 3
    Introduction
    Leptomeningeal rheumatoid nodules are a rare condition. This case demonstrates the unique presentation and diagnostic workup for the distinctive condition and highlights the difficulties surrounding therapeutics..
    Case Presentation
    A 67 year old woman presented with recurrent transient ischaemic attack-like episodes over a 2 year period. Nodular enhancing leptomeningeal changes were detected on MRI and consistent with meningeal rheumatoid nodules on biopsy. The patient’s nodular disease continued to progress and regress clinically and radiologically irrespective of disease modifying agents and peripheral and serological rheumatoid arthritis control..
    Conclusions
    This patient’s unique presentation and diagnostic work-up is discussed alongside the dilemma of therapeutic management of meningeal rheumatoid nodules..
    Keywords: Leptomeningeal, Rheumatoid, Nodules, Pachymeningitis, Tocilizumab, Brain, Biopsy
  • Laura K. Cohen, Matthew B. Jensen * Page 4
    Context: Intracerebral grafting of neural progenitor cells is a promising potential treatment to improve recovery after stroke, but the structural disruption and cavitation of brain tissue that occurs creates an unfavorable environment for graft cell survival. To overcome this obstacle, scaffold materials have been used as extracellular matrix to provide structural support for the transplanted cells. Many materials could potentially be used as scaffolds for this application..Evidence Acquisition: We performed a systematic review to determine the available evidence supporting specific scaffolds for neural progenitor cell grafting after stroke. Articles were identified with a MeSH search on PubMed. Relevant references and “related articles” of selected manuscripts were also reviewed. Full original articles published prior to May 2013 presenting unique experimental data describing intracerebral grafting of neural progenitor cells in a scaffold after cerebral infarction were included in our study. All selected articles were reviewed thoroughly by the authors for relevant data..
    Results
    We found reports of use of scaffolds composed of polyglycolic acid, poly [lactic-co-glycolic acid] particles (with and without VEGF), hyaluronan-heparin-collagen hydrogel, Matrigel, collagen and extracellular matrix derived from porcine brain and urinary bladder. While multiple beneficial effects were reported, the optimal scaffold is unclear as we found no direct comparisons..
    Conclusions
    We conclude that multiple scaffolds appear promising for neural progenitor cell grafting after stroke, but further research is needed to optimize this neurorestorative approach. Thus, we hope to provide a basic understanding of the state of scaffolds for neural progenitor cell grafting after stroke and to encourage further research. Based on the methods of the discussed studies, we propose a standardized set of outcomes that would best be used to evaluate and compare the effectiveness of a given scaffold..
    Keywords: Scaffold, Bio Scaffold, Neural Progenitor Cells, Grafting, Extracellular Matrix, Hydrogel, Neural Stem Cells, Stroke, Transplantation
  • Vali Shiri, Ali S. Hosseini, Ali Tahmasebi *, Ebrahim Pishyareh, Esmail Shiri, Mahbobeh Emami Page 5
    Background
    The association of autism symptoms and cognitive abilities can facilitate the etiology and treatment of autism disorders. Destruction of executive functions is one of the several potential cognitive phenotypes in autism..
    Objectives
    The purpose of this study was to investigate the relationship between deficit executive functions and behavioral symptoms in children with high-functioning autism..
    Materials And Methods
    In this cross-sectional study, 50 children with high-functioning autism were selected using the convenience sampling method. The Gilliam autism rating scale, high-functioning autism spectrum screening questionnaire, The Stroop color and word test, continuous performance test and shifting attention test were administered. Pearson correlation coefficient and multi-variant regression were used to analyze the data..
    Results
    There was a positive correlation between selective attention with communication and social interactions (P < 0.01, P < 0.05). There was a positive correlation between sustained attention with social interactions and stereotyped behaviors (P < 0.05, P < 0.001). Moreover, there also was a positive correlation between shifting attention and communication, social interactions and stereotyped behaviors (P < 0.05, P < 0.01, P < 0.001). The results of regression analysis showed that selective attention and shifting attention can predict communication (P < 0.01). Sustained attention can predict social interactions and stereotyped behaviors (P < 0.01, P < 0.05)..
    Conclusions
    The results of this study suggest that executive functions play an important role in symptoms of children with high-functioning autism. It is recommended to design new therapeutic interventions to restore executive functions in children with high-functioning autism..
    Keywords: Executive Function, Attention, High Function Autism
  • Seyede Zahra Emami Razavi, Arvin Aryan, Shahrbanoo Kazemi, Abdolrahman Rostamian, Azadeh Jahangiri, Mahsa Ghajarzadeh * Page 6
    Background
    Heterotopic ossification (HO) is a complication after spinal cord injury. There are limited studies evaluating hip ossification in Iranian patients with spinal cord injury..
    Objectives
    We designed this study to evaluate prevalence of HO in cases with spinal cord injury and clinical factors related to this finding..Patients and
    Methods
    In this study, 135 patients with traumatic spinal cord injury who were referred to a spinal cord injury clinic were enrolled. A structured questionnaire was used to collect data. Hip radiography was performed for all patients to evaluate hip ossifications. An expert radiologist assessed the obtained radiographs..
    Results
    Thirty one (23%) participants were women and 104 (77%) were men. The most common cause of injury was accident (66.7%) followed by falling (28.1%). HO was present in 51 (37.8%) cases, and hip X-ray was normal in 84 (62.2%) Duration of injury and bed sore were significantly higher in patients with HO. Logistic regression analysis considering HO as a dependent variable showed that only bedsore was an independent predictor of HO..
    Conclusions
    Evaluation for hip ossification should be considered in patients with spinal cord injury..
    Keywords: Hip, Bone Formation, Spinal Cord Injuries
  • Kavita Singh, Richa Trivedi *, Maria M. Dsouza, Ajay Chaudhary, Subash Khushu, Pawan Kumar, Ram K. S. Rathore, Rajendra P. Tripathi Page 7
    Background
    Traumatic brain injury (TBI) has been shown to predominantly affect the corpus callosum (CC). In light of the anatomical organization of cortico-callosal connections, we hypothesized that injury to the different cortical lobes may specifically affect their corresponding subdivisional fibers in the CC..
    Objectives
    The aim of this study was to investigate lesion-related Wallerian degeneration across the subdivisions of the CC in patients with moderate TBI..Patients and
    Methods
    Diffusion tensor tractography (DTT) was performed between 14 days and 6 months after trauma in 18 patients with moderate TBI, and 11 age- and gender-matched healthy control subjects. Based on conventional magnetic resonance imaging findings, patients were classified into 3 groups: A) frontal lobe injury; B) occipito-temporal lobe injury; and C) fronto-parieto-temporal lobe injury. The CC was divided into seven subdivisions based on Witelson’s classifications. Fractional anisotropy (FA) and mean diffusivity (MD) values from the seven segments were compared among patient groups and controls..
    Results
    Compared to controls, Group A showed significantly reduced FA in the rostrum, genu, splenium, and CC. Group B showed significantly reduced FA in the isthmus and whole CC relative to that in the controls. In Group C, FA significantly decreased across the entire CC compared to that in the controls..
    Conclusions
    In our study, subdivisional fibers of the CC showed secondary microstructural changes resulting from primary injury in the corresponding cortical areas. We conclude that DTT-derived measures may act as an indicator of ongoing Wallerian degeneration. By extension, this study may improve our understanding of variable neuropsychological outcomes in clinically similar patients with TBI..
    Keywords: Brain Injuries, Wallerian Degeneration, Corpus Callosum, Diffusion Tensor Imaging, Fractional Anisotropy
  • Farshad Nemati * Page 8
    Jean Piaget accorded the adaptive role of acting on objects in the formation of logical structures a priority during development. According to his studies, correspondence between the structure of spatial behavior in infants and mathematical properties of “group of displacements” implies the development of such logical constructs even before the appearance of language. In the present analysis, it will be demonstrated that such mathematical structures can also be inferred from spatial behavior of the rat (Rattus Norvegicus) and some other species. However, despite such correspondence, there are dissimilarities in the performance of different species. Such similarities and differences will be discussed in relation to the formation of abstract processes and cognitive competence across species. The analysis supports the philosophical notion that different phenomena may have parallel mathematical descriptions but whether or not they are the same always has to be examined at the conceptual level as well..
    Keywords: Cognitive Development, Evolution, Infancy, Intelligence, Spatial Behavior, Rats
  • Zahra Tolou-Ghamari * Page 9
    Background
    Previous publications categorized Isfahan as a high-risk area with regard to the prevalence and incidence of multiple sclerosis (MS)..
    Objectives
    Till to date, there have been no studies differentiating between the prevalence of MS in Isfahan and its rural provinces..Patients and
    Methods
    A retrospective study of 4,209 patients with MS was conducted and recorded by the deputy of health at the Isfahan university of medical sciences in 2013. Demographic variables and place of birth were recorded in Excel. Descriptive and comparative analyses were conducted using SPSS..
    Results
    For Isfahan and its rural provinces, the calculated prevalence of MS could be referred as P = 84.14. The calculated prevalence of MS for Isfahan was as P = 27.61. It seems that the highest MS populations are located in the Isfahan rural southwest provinces. The place of birth in 52% was Isfahan. The number of women (78%) was higher than that of men (22%), and 90% of the population was young (range: 20 - 50 years old)..
    Conclusions
    The outcome of this preliminary study suggested that Isfahan and its rural provinces might be categorized as two distinct regions for epidemiology of MS. Medium-risk areas included Isfahan, and high-risk areas included the Isfahan rural southwest provinces. Further advanced studies in this direction are recommended..
    Keywords: Birthplace, Regions, Prevalence, Multiple Sclerosis
  • Tohru Nitta * Page 10
    Context: Recently, the singular points of neural networks have attracted attention from the artificial intelligence community, and their interesting properties have been demonstrated. The objective of this study is to provide an overview of studies on the singularities of complex-valued neural networks..Evidence Acquisition: This review is based on the relevant literature on complex-valued neural networks and singular points..
    Results
    Review of the studies and available literature on the subject area shows that the singular points of complex-valued neural networks have negative effects on learning, as do those of real-valued neural networks. However, the nature of the singular points in complex-valued neural networks is superior in quality, and the methods for improving the learning performance have been proposed..
    Conclusions
    A complex-valued neural network could be a promising learning method from the viewpoint of a singularity..
    Keywords: Neural Network, Learning, Non, linear Dynamics