فهرست مطالب

  • Volume:1 Issue:3, 2014
  • تاریخ انتشار: 1393/02/17
  • تعداد عناوین: 11
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  • Jie Yang *, Hua Shu Page 1
    Background
    The role of the sensory-motor system in semantic representation has caused increasing research interest. Although previous studies have shown different activations in the motor system during action verb processing, motor imagery and action execution, whether motor system interaction is modulated by task demand is still unknown..
    Objectives
    To address the issue, the current study used effective connectivity analysis to investigate how task demand influences causal interactions among bilateral supplementary motor areas (SMA) and primary motor cortex (M1)..
    Materials And Methods
    Nineteen participants performed a verb reading task, a motor imagery task, and a hand motion task in an fMRI experiment, and their brain activity related to task performances was examined. Granger causality analysis was used to compute causal interactions among activity in the bilateral M1 and bilateral SMA in three tasks..
    Results
    Granger causality analysis indicated that the hand motion task elicited the most complicated network and that the passive reading task elicited the fewest connections among the four areas. Furthermore, only the passive reading task elicited left lateralized connectivity between M1 and SMA. In addition, motor imagery and hand motion execution elicited negative influences from the right SMA to other areas..
    Conclusions
    These results together suggest that although the motor network involved in action verb processing shared some interactions with those in motor imagery and hand motion execution, semantic representation during language comprehension is different from the raw sensory-motor experiences supported by the primary cortical areas..
    Keywords: Brain, Comprehension, Imagery (Psychotherapy), Language, Magnetic Resonance Imaging, Motor Activity, Motor Cortex
  • Yuya Harada, Yuki Nagao, Takahiro Mukai, Saki Shimizu, Kentaro Tokudome, Naofumi Kunisawa, Tadao Serikawa, Masashi Sasa, Yukihiro Ohno * Page 2
    Background
    The inwardly rectifying potassium channel subunit Kir4.1 is specifically expressed in astrocytes, which mediates spatial K+ buffering and is implicated in the pathogenesis of convulsive epileptic disorders (ie, generalized tonic-clonic (GTC) and temporal lobe seizures)..
    Objectives
    This study aimed to explore the pathophysiological role of Kir4.1 channels in modulating absence seizure incidence, using a spontaneously epileptic animal model..
    Materials And Methods
    Groggy rats, a rat model of human absence seizures, and Slc:Wistar (control) rats, were used in this study. Cortical and hippocampal EEG were recorded to confirm the seizure incidence in Groggy rats. The expression levels of Kir subunits (ie, Kir4.1, Kir5.1 and Kir2.1) in ten brain regions were analyzed by Western blotting..
    Results
    Groggy rats showed a high incidence (ca. 350 seconds total duration/15 minutes observation period) of absence-like seizures, which were characterized by a sudden immobile posture and synchronously-associated spike and wave discharges. However, Western blot analysis revealed that Kir4.1 expression in Groggy rats was not significantly different from that of control rats in any of the brain regions examined (eg, cerebral cortex, striatum, hippocampus, diencephalon, midbrain, pons/medulla oblongata and cerebellum). In addition, expressional levels of Kir5.1 and Kir2.1, which are also expressed in astrocytes, were unaltered in Groggy rats..
    Conclusions
    The present results suggest that unlike GTC and temporal lobe seizures, pathophysiological alterations (eg, dysfunction and/or expressional changes) of Kir4.1 are not linked to non-convulsive absence seizures..
    Keywords: Astrocytes, Rat, Epilepsy, Absence
  • Francesco Raudino * Page 3
    Background
    Only few studies evaluated the long-term effectiveness of the prophylactic therapy of migraine..
    Objectives
    In this study we evaluate the optimal length of the prophylaxis in migtaineurs..Patients and
    Methods
    The length of the prophylactic therapy was evaluated in 68 outpatients with migraine without aura. The drugs dosage was adjusted upon clinical response while maintaining the aim of reducing the headaches frequency by at least 75%. Following a minimum of three months of well-being, a gradual tapering of the tested drug was attempted; whenever this resulted in worsening conditions, the original dosage was restored. The follow-up lasted from a minimum of one year to a maximum of five years..
    Results
    The prophylaxis mean length was 15.4 ± 15.3 months, ranging from two to 60 months; 33 (48.5%) patients with migraine required longer than one year of prophylaxis. In 14 (36.8%) patients with migraine who worsened after withdrawal of the prophylaxis, the drug previously effective became ineffective when prescribed again..
    Conclusions
    According to the recent studies, a significant number of patients require longer prophylaxis than usually advised by the guidelines. Besides, in a significant number of patients, one drug previously effective became ineffective if prescribed again after suspension..
    Keywords: Migraine Disorders, Long, Term Migraine Prophylaxys
  • Seyedeh Mohadeseh Taheri Otaghsara, Marzieh Matin, Sahar Latifi *, Abbas Norouzi Javidan, Davood Koushki Page 4
    Background
    Depression is a major health problem that has been shown to cause decreased function and associated with several chronic states of disability..
    Objectives
    The aim of this study was to investigate the prevalence of depression in caregivers of spinal cord injury patients in Iran..Patients and
    Methods
    Caregivers of patients with spinal cord injury (SCI), who were referred to the Brain and Spinal Injury Research Center (BASIR), were interviewed to assess the existence of depression based on DSM-IV criteria. Patients’ injury characteristics, including; injury level, etiology and independence scores, based on the Spinal Cord Independence Measure (SCIM), were entered into the analysis..
    Results
    Among the caregivers; 82.6% (n = 119) had no depressive disorder, while 9.7% (n = 14) revealed mild depression, 5.6% (n = 8) had moderate depression, and 2.1% (n = 3) suffered from a severe depressive disorder. Caregivers of patients with lower SCIM scores had significantly higher rates of depressive episodes (P < 0.001). Higher injury levels were also associated with higher depression rates among caregivers (P < 0.004)..
    Conclusions
    The incidence of depression in the caregivers of spinal cord injured patient does not differ significantly from the general population in Tehran, Iran. It seems that the major predictor of developing depression in caregivers is the dependency level of the patient. Our study recommends developing screening programs to diagnose and treat depression, which target caregivers of spinal cord injury individuals with severe injuries, particularly those with higher levels of dependency, in order to reduce the burden and consequences of depression in this sensitive population..
    Keywords: Depression, Spinal Cord Injuries, Caregivers
  • Zohreh Habibi *, Zaker Saedinejad, Owrang Eilami Page 5
    Background
    Administration of prophylactic antibiotics for disc surgery is accepted by most surgeons, but no universal protocol exists..
    Objectives
    To determine the safety and effectiveness of single dose preoperative antibiotics alone in preventing wound infections following single level lumbar laminectomy with or without discectomy.. Patients and
    Methods
    We reviewed 117 consecutive patients (68 males and 39 females) who underwent single-level lumbar laminectomy and medial facetectomy for lumbar stenosis, with or without discectomy during a ten-month period. Two grams of intravenous cefazolin was administered at the induction of general anesthesia. During the postoperative period, either in hospital or at home, additional antibiotic prophylaxis was not administered. The wounds were inspected on the first day of surgery at the time of indwelling catheter removal, 10-14 days after surgery for suture removal, and 4 to 6 weeks after discharge..
    Results
    Superficial wound redness was detected in 2 patients (1.7%), which improved with oral antibiotic, and 1 patient (0.85%) developed discitis which improved with nonsurgical management. None of the patients needed surgical re-exploration for infection or other complications..
    Conclusions
    The current retrospective study proved that our antibiotic prophylaxis protocol is safe and efficacious. Assuming that a wound infection rate of about 2% is considered acceptable after a clean spinal operation, a 1.7% rate for superficial incisional wound infections is promising. Also, as the incidence of discitis following discectomy has been reported to be between 0.75% and 3.0%, 0.85% rate of discitis in our series seems acceptable.
    Keywords: Antibiotic Prophylaxis, Intervertebral disc disease, Lumbosacral Region, Wound Infection
  • Parichehr Hassanzadeh * Page 6
    Context: Involvement of the endocannabinoid system (eCBs) in a wide variety of physiological and pathological processes has attracted a growing interest. In fact, identification of this ubiquitous signaling system has provided new insights into the underlying pathophysiologic mechanisms of various diseases which may lead to development of novel therapeutic strategies..Evidence Acquisitions: The limited efficacy of current pharmacological treatments for neurological disorders has led to considerable research interests in new drug development. Based on the modulatory effects of the eCBs on neuroinflammatory and neurodegenerative processes, pharmacological manipulation of the eCBs may prove beneficial in neurological problems..
    Results
    The eCBs is involved in the survival signaling pathways, neural plasticity, and neuroprotection. Furthermore, the eCBs has proved therapeutic effects against the neurological diseases such as multiple sclerosis, epilepsy, mood and movement disorders, spinal cord injury, stroke, and Alzheimer’s disease..
    Conclusions
    In the present manuscript, an overview on the regulatory role of the eCBs in neurological disorders underscores the importance of systematic analysis of the efficacy and mechanisms of action of cannabinoid-based drugs. Based on the anti-neuroinflammatory and anti-neurodegenerative effects of cannabinoids, the development of drugs without psychoactive effects would be a promising therapeutic alternative for neurological diseases..
    Keywords: Endocannabinoids, Nervous System Diseases, Nerve Degeneration
  • Patrick Colm Hogan * Page 7
    Introduction
    Esthetic response appears to result from the interaction of specifiable forms of information processing (prototype approximation and non-habitual pattern recognition) with particular emotional or motivational systems, such as the endogenous reward system. One likely emotional component of such response is the object attachment or bonding system. Earlier essays have articulated a framework along these lines, but provided only limited support for the role of attachment..Arguments: The present discussion article advances further explanatory advantages for an analysis of esthetic pleasure that includes attachment activation as a central component. In connection with this activation, this study takes up further research on neural correlates of the enjoyment of music and the medical outcomes of listening to music. The advantages of such an analysis also include an account of some philosophical observations about the nature of aesthetic response, specifically the orientation of esthetic feeling toward particular objects and the recurrence of certain preferred subjects for artistic depiction..
    Conclusions
    These arguments suggest that the attachment system may play a significant role in esthetic response generally and even in some unexpected aspects of aesthetic response. At the same time, they raise further questions, for example questions concerning the mechanisms by which attachment system activation might operate in esthetic response..
    Keywords: Beauty, Object Attachment, Esthetics, Literature, Music
  • Michael A. Persinger * Page 8
    The persistence of 10-20 J as the fundamental unit of interaction between the most fundamental electromagnetic and molecular interactions within physical-chemical and biological systems reflects a universal origin. This quantity becomes apparent when the energetic parameters associated with the future (final) epoch of the universe are applied at the level of the smallest length. The quantum is a primary solution for the Bohr frequency for specific electron shells and the integrative quantity between the action potential of the neuron and the bulk velocity of the entire cerebral electromagnetic field when applied to the equations for de Broglie waves and Heisenberg uncertainty. The continuous and serial transformation of the 10-20 J quanta within cellular and brain space could replace the myriad of molecular pathways to a single and fundamental operator. Because the difference between the energy equivalence for an electron’s classic and Compton wavelength width by a Lorentz transform is about 10-20 J, this quantity, when applied appropriately, could facilitate the collapse of wave functions within brain space..
    Keywords: Action Potentials, Bohr frequency, Genetic Vectors, Consciousness
  • Alireza Khoshnevisan *, Sina Abdollahzadeh Page 9
    Introduction
    Localization and delineation of the extent of lesions are critical for safe management of brain tumors and vascular abnormalities. Neuronavigation systems have been developed for image-guided neurosurgery to aid accurate localization and better visualization of these lesions. Navigation has been mainly used in brain biopsy and tumor resection. There have been a few reports on its use in vascular surgery and they suggest that neuronvigation could be helpful..
    Case Presentation
    A 53-year-old man developed a severe sudden headache 2 days before admission. He did not have any specific medical problems. On inspection of neurological status, he was alert and his motor power was normal in all extremities. CT scan on admission showed diffuse blood in sylvian fissures and basal cisterns. Angiography revealed an aneurysmal dilatation where the posterior communicating artery arises from the right internal carotid artery (ICA). MRI scan with appropriate protocol for neuronavigation was performed and demonstrated, on Gadolinium (Gd) enhanced images, a small round hyperintense lesion in parasellar region on the right side. We prepared the navigation based on CT scan and MRI for surgery of the aneurysm. Right frontotemporal craniotomy was performed, brain retracted and arachnoid membranes were opened under the guidance of navigation-MRI. The neck was dissected and a clip was applied to the aneurysm. Neurological status of the patient was unchanged postoperatively and control CT scan was unremarkable..
    Discussion
    According to the reports and our case we suggest that MRI based neuronavigation results in accurate localization of the aneurysm, increases visualization of the lesion, decreases normal parenchymal and vascular injury and is useful for the treatment of ruptured intracranial aneurysms in special cases..
    Keywords: Intracranial Aneurysm, Neuronavigation, Surgical Procedures, Minimally Invasive
  • Jeremy Christopher Ganz * Page 10
    James Hill began his surgical career in Dumfries in 1732. He had not received any formal training in operation technique. He was the son of an illegitimate Presbyterian minister who suffered from depression and who was much distressed by the interference of the state in his parish. Dr. Hill married a woman whose family had also suffered from the conflicts between the Episcopalian and Presbyterian churches. Hill، despite the importance of religion in his home life was much influenced by the Scottish Enlightenment with its emphasis on evidence rather than authority. He pursued this principle of basing his practice on experience and observation rather than on received wisdom. In a book he wrote ‘Cases in Surgery’ published in 1772 he presents 18 patients who had suffered cranial trauma. By reason of his approach، and presumably also because of considerable surgical skill he managed to achieve surgical results which were the best of his century. He was much respected by colleagues and those who came after but he has undeservedly been forgotten. The purpose of this paper is to present his achievements in support of the contention that this great surgeon deserves to be re-instated as a significant contributor to the early management of cranial trauma..
    Keywords: Scotland, History, 18th Century, Craniocerebral Trauma
  • Majid Ghaffarpour *, Hossein Ali Ghelichnia, Mohammad Hossein Harrichian, Mojdeh Ghabaee, Mohammad Mahdi Saber Tehrani, Parviz Bahrami Page 11
    Context: Seizure is a transient neurologic dysfunction caused by sudden abnormal firing of cerebral neurons. Epileptic syndrome is a complex of symptoms and signs that is characterized by not only the etiology but also the age at onset, seizure type, pattern of electroencephalography and prognosis..Evidence Acquisition: Treatment of the first seizures depends on their nature; some of them need no antiepileptic drugs (AED) therapy whereas the others should be treated appropriately. AEDs have long- and short-term adverse effects, interaction with other medications, and occupational and/or psychological consequences. Therefore, discontinuation of AEDs should be considered after a free-seizure period..
    Results
    Studies show that the rate of seizure recurrence after AEDs withdrawal is about two to three times more than those who continue therapy; thus, the most difficult decision facing a neurologist is when to start medication and when/how it should be discontinued..
    Conclusions
    This review explores the literature to answer above questions..
    Keywords: Seizures, Epilepsy, Anticonvulsants