فهرست مطالب

Basic and Clinical Neuroscience
Volume:9 Issue: 1, Jan - Feb 2018

  • تاریخ انتشار: 1396/12/09
  • تعداد عناوین: 8
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  • Milad Rahimzadegan, Maliheh Soodi * Pages 5-14
    Introduction
    Scopolamine, a muscarinic cholinergic receptor antagonist, is widely used to induce memory impairment in experimental animals. The present study aims to compare memory impairment and oxidative stress following single and repeated doses administration of scopolamine.
    Methods
    A group of rats received a single shot of scopolamine in different doses (0.5, 1, or 3 mg/kg, IP) 24 hours after the passive avoidance training. Then the memory retrieval test was performed 30 minutes and 7 days after the injection. In the other experiment, rats received similar doses of scopolamine for 7 consecutive days, 24 hours after the training session. Then the memory retrieval test was performed 30 minutes and 7 days after the last injection. Acetylcholinesterase (AChE) activity and lipid peroxidation were measured in their hippocampus tissue, too.
    Results
    Scopolamine administered in repeated doses caused more impairment in memory function compared to single dose injection based on the evaluation 30 minutes after injection. Moreover, the memory impairment persisted for 7 days only in repeated doses treated groups. Increase in acetylcholinesterase activity and lipid peroxidation in both groups was observed 30 minutes after scopolamine administration. These abnormal increases persisted for 7 days only in repeated doses treated groups. Increased AChE activity and lipid peroxidation was well correlated with behavioral deficit. Also AChE activity was well associated with lipid peroxidation.
    Conclusion
    The results of present study showed that repeated administration of scopolamine induced results in memory impairment. This effect can be due to long-lasting oxidative stress which may damage the hippocampus tissue.
    Keywords: Scopolamine, Oxidative stress, Acetylcholinesterase, Memory
  • Afsane Zadnia, Hamid Reza Kobravi *, Mania Sheikh, Hossein Asghar Hosseini Pages 15-26
    Introduction
    Application of biofeedback techniques in rehabilitation has turned into an exciting research area during the recent decade. Providing an appropriate visual or auditory biofeedback signal is the most critical requirement of a biofeedback technique. In this regard, changes in Surface Electromyography (SEMG) signals during wrist movement can be used to generate an indictable visual biofeedback signal for wrist movement rehabilitation via SEMG biofeedback. This paper proposes a novel methodology for selecting the most appropriate features out of wrist muscle SEMG signals.
    Methods
    To this end, the surface EMG signals from flexor and extensor muscle groups during wrist joint movements were recorded and analyzed. Some linear and nonlinear features in frequency, time, and time-frequency domains were extracted from the recorded surface EMG signals of the flexor and extensor muscles. Experiments and analyses were performed on ten healthy subjects and four stroke patients with wrist muscle spasticity as the movement disorder subjects. Some heuristic feature selection measures were applied. The main motivation behind choosing applied heuristic feature selection measures was meeting. In the first step, the designed visual biofeedback signal should indicate a healthy wrist motion profile as its successful tracking by the patient guarantees rehabilitation. In addition, the visual biofeedback signal should be a smooth curve thus preventing the patient from discomfort while tracking it on a monitor during the biofeedback therapy.
    Results
    In this pilot study, after using the introduced feature selection measures, quantitative and qualitative analyses of the extracted features indicated that Shannon entropy is the most appropriate feature for generating a visual biofeedback signal as a healthy wrist motion profile to improve the ability of stroke patients in controlling wrist joint motion. In addition, it was shown that when the wrist joint moves between a flexed and rest position, the flexor muscle EMG signal should be used for generating a visual biofeedback signal. However when the wrist joint moves between a rest position and an extended position, the extensor muscle EMG signal is appropriate for providing a visual biofeedback signal. It is worth noting that the achieved pilot study results should be confirmed by the future studies with larger samples.
    Conclusion
    According to the obtained results, it can be concluded that among the analyzed features, the Shannon entropy was the most appropriate feature. It can be employed for generating a visual biofeedback signal for reduction of spasticity in patients with stroke.
    Keywords: Biofeedback, Muscle spasticity, Stroke, Electromyography
  • Hengameh Dortaj, Maryam Yadegari, Mohammad Hosseini Sharif Abad, Abolghasem Abbasi Sarcheshmeh, Morteza Anvari * Pages 27-34
    Introduction
    Acrylamide (ACR) consumption is increasing all over the world. There are some evidence on the literature about its neurotoxic effect on mature animals, but the effects of ACR on postnatal development have been less studied. The purpose of this study was to evaluate the effects of ACR on development of cortical layer, white matter, and number of Purkinje cells of the cerebellum in rat newborns.
    Methods
    This study was carried out on 20 female Wistar rats (average weight: 180 g, aged: two months). The rats were divided into four groups. Pregnant rats were orally fed with ACR 10 mg/kg and vitamin C 200 mg/kg. In this study, 6 infants of each group (weighting 32-35 g) were randomly selected at day 21 after birth and placed under deep anesthesia and transcardial perfusion. Their cerebellums were fixed and histopathological changes were evaluated with Hematoxylin and Eosin (H&E) staining and cresyl violet method. The volume of cerebellar cortical layers and number of Purkinje cells were investigated by Cavalieri’s principle and physical dissector methods. The obtained data were analyzed by 1-way ANOVA and LSD test using SPSS. P
    Results
    The results showed that newborns of ACR-treated female rats have decreased cerebellar weight (P≤0.05) and lower than average number of Purkinje cells (P≤0.001). ACR also decreased the volume of granular and molecular layer and increased the volume of white matter. While the results showed decreased in white matter volume in vitamin C group (P≤0.001).
    Conclusion
    ACR induces structural changes in the development of the cerebellar cortical layers in rat newborns, but these changes may be prevented by vitamin C as an antioxidant.
    Keywords: Acrylamide, Cerebellum, Vitamin C, Stereology, Neurotoxicity
  • Salime Jafari, Amin Modarresszadeh, Ahmad Reza Khatoonabadi *, John Hodges, Noureddin Nakhostin Ansari, Cristian Leyton, Maryam Noroozian Pages 35-42
    Introduction
    Primary Progressive Aphasia (PPA) is a neurological condition characterized by progressive dissolution of language capabilities. The Progressive Aphasia Language Scale (PALS) is an easy-to-apply bedside clinical scale capable of capturing and grading the key language features essential for the classification of PPA. The objective of the present study was to develop and validate the Persian version of the PALS (PALS-P) as a clinical language assessment test.
    Methods
    In this cross-sectional study, PALS was translated and adapted into Persian according to the international guidelines. A total of 30 subjects (10 subjects with PPA and 20 control subjects without dementia) were recruited to evaluate the intra-rater reliability and discriminant validity of PALS-P.
    Results
    The intra-rater reliability of the PALS-P within a 14-day interval was excellent for each subtest (ICC agreement range=0.81-1.0). PALS-P results were statistically significant among groups, suggesting its discriminative validity.
    Conclusion
    This preliminary study indicates that PALS-P was successfully developed and translated. It seems to be a valid and reliable screening tool to assess language skills in Persian-speaking subjects with progressive aphasia.
    Keywords: Aphasia, Neurodegenerative disorders, Primary progressive aphasia, Language test
  • Kazuhiro Hayashi *, Tatsunori Ikemoto, Takefumi Ueno, Young-Chang Park Arai, Kazuhiro Shimo, Makoto Nishihara, Shigeyuki Suzuki, Takahiro Ushida Pages 43-50
    Introduction
    Facial expression to pain is an important pain indicator; however, facial movements look unresponsive when perceiving mild pain. The present study investigates whether pain magnitude modulates the relationship between subjective pain rating and an observer’s evaluation of facial expression.
    Methods
    Twelve healthy volunteers were recruited to obtain 108 samples for pain rating with Visual Analogue Scale (VAS). Subjects underwent three different mechanical painful stimuli (monofilament forces of 100 g, 300 g, and 600 g) over three sessions and their facial expressions were videotaped throughout all sessions. Three observers independently evaluated facial expression of the subjects with a four-point categorical scale (no pain, mild pain, moderate pain, and severe pain). The correlations between subjective pain ratings and the evaluation of facial expression were analyzed in dichotomous group which was low pain ratings (VAS
    Results
    Subjective pain ratings was significantly correlated with the evaluation of facial expression in high pain ratings, however no correlation was found between them in mild pain ratings. In mild pain ratings, most of the subjects (78%) were rated as no pain by observers, despite the fact that subjects reported pain.
    Conclusion
    The results suggest that the evaluation of facial expression of pain was difficult for the observer to detect pain severity when the subjects feel mild pain.
    Keywords: Pain assessment, Pain perception, Face
  • Khadijeh Esmaeilpour, Vahid Sheibani, Mohammad Shabani, Javad Mirnajafi-Zadeh *, Zeinab Akbarnejad Pages 51-58
    Introduction
    The life quality of patients with epileptic seizures is highly affected by cognitive deficits. Low Frequency Stimulation (LFS) is a novel approach for the treatment of pharmacoresistant epilepsy. The main goal of this research is investigating the possible effect of LFS on seizure-induced cognitive dysfunction.
    Methods
    To this end, the kindled animal were prepared via CA1 electrical stimulation in a semi-rapid way (12 stimulations/day). A group of animals were stimulated with LFS, 4 times at 30 s, 6 h, 24 h, and 30 h after the last kindling stimulation. Applied LFS was administered in 4 packages every 5 minutes. The packages were designed with 200 monophasic 200 monophasic square wave pulses of 0.1 ms duration at 1 Hz. The passive-avoidance test was conducted on all animals in order to measure the learning and memory behavior.
    Results
    Hippocampal kindled rats showed deficits in learning and memory when passive avoidance test was performed. Application of LFS reversed the impairment in learning and memory behavior in kindled rats. At the same time, LFS markedly diminished kindling-induced neuronal loss and atrophy in the hippocampus.
    Conclusion
    LFS may have some protection against seizure-induced cognitive damage in kindled rats.
    Keywords: Epilepsy, Learning, memory, Low, frequency stimulation, Kindling
  • Mohammad Vahedi, Mehrdokht Mazdeh, Mehrdad Hajilooi, Maryam Farhadian, Yasamin Barakian *, Parastoo Sadr Pages 59-64
    Introduction
    Tension-type headache is the most common type of headache across the world. Saliva as a non-invasive medium is used to detect a wide range of diseases. Salivary Alpha-Amylase (SAA) levels has been suggested as a potential indirect marker for detecting Sympathoadrenal Medullary (SAM) activity, which is activated by pain. Significant correlation was found between SAA levels and pain scale in patients with chronic pain. The purpose of the present study was to measure SAA activity in Frequent Episodic Tension-Type Headache (FETTH). In addition to the Visual Analogue Scale (VAS), we intend to assess intensity and various aspects of pain by McGill Pain Questionnaire (MPQ).
    Methods
    A total of 45 females with FETTH (case group) and 45 healthy voluntary females (control group) were enrolled in our case-control study. Unstimulated saliva by spitting method was taken from each participant.
    Results
    SAA levels were significantly higher in patients with FETTH (P
    Conclusion
    This is the first study using MPQ as a subjective means of assessing quality and quantity of pain alongside the VAS as an objective tool for evaluating pain in patients with FETTH. SAA may be an appropriate marker for assessing of pain levels in patients with FETTH. MPQ versus the VAS may be a more accurate measurement tools along VAS.
    Keywords: Pain measurement, Salivary Alpha Amylase, Tension, type headache
  • Mahsa Zare, Fariborz Faeghi, Ashrafsadat Hosseini *, Mohammad Sobhan Ardekani, Mohammad Hossein Heidari, Ehsan Zarei Pages 65-71
    Introduction
    The present study aims to evaluate the Three-Dimensional Diffusion-Weighted reversed fast imaging with steady state free precession (3D DW-PSIF) sequence with respect to imaging of the peripheral nerves; the tibial, medial, and lateral plantar nerves in the lower extremity, ulnar and median nerve in the upper extremity, sciatic nerve, brachial plexus, and lumbosacral plexus, and also to compare its usefulness with the current two-dimensional sequences on a 1.5 T MR scanner.
    Methods
    A total of 25 healthy subjects underwent MR imaging of peripheral nerves, 5 subjects in each area. In each imaging sequence, including T2W SPAIR and 3D DW-PSIF, images were evaluated for ability to identify the nerves in the related area using a 3-score scale (0-2). Then, by summing up the conspicuity scores, a total certainty score was recorded for each sequence.
    Results
    With combining the results of all studies, the conspicuity mean (SD) score was 1.57(0.67) on the 3D DW-PSIF images, and 0.74(0.76) on the T2-weighted images (P
    Conclusion
    3D DW PSIF provides better manifestation of nerves compared to routine imaging sequences particularly fat saturated T2W images. This novel imaging technique can be used in MR neurography examination protocol for exact localization of the nerve and evaluation of the nerve pathology.
    Keywords: MR neurography, 3D DW PSIF, Peripheral nerves, Lumbosacral plexus, Brachial plexus