فهرست مطالب mahshid tahamtan

Mild Cognitive impairment (MCI) is a primary disorder intensifies by aging. Rapid diagnosis of MCI can prevent its progression towards the development of dementia. Thus, the present study was conducted to evaluate the psychometric features of the self-assessment Persian version of Alzheimer's questionnaire (AQ) in the elderly to detect MCI. 

First, the Alzheimer's questionnaire was translated into the Persian language; then, content validity was evaluated by CVI and CVR method, face validity was determined by two checklists for expert panel and the elderly. Convergent validity of the MCI test with MoCA was assessed using Pearson correlation. Test-retest and internal consistency reliability using Intra-Class Correlation (ICC) and Kuder-Richardson coefficients, respectively, were evaluated; moreover, the receiver operating characteristic curve was used to determine the optimal cut-off point of self-assessment MCI test. Among 148 older people took part, 93 of them meet our inclusion criteria (aged 60 years old or older, had reading and writing skills and able to speak and communicate).

A translated version of the questionnaire was named “M-check”. The developed test showed good content and face validity. Statistically significant correlations were found between M-check and MoCA (r= -0.83, p < 0.05). Kuder–Richardson and ICC coefficient were obtained as 0.84 and 0.92, respectively. Area under the curve presented satisfactory values (AUC =0.852, sensitivity =0.62, specificity =0.94).

M-check is a reliable tool that can be used as a valid and reliable instrument for assessing cognitive state and screening dementia in the elderly.

Acute Kidney Injury (AKI) is a frequent complication of kidney failure with high mortality, leading to brain dysfunction. This study aimed to investigate the possible protective effect of Ischemic Postconditioning (IPo) against brain dysfunction induced by Bilateral Renal Ischemia (BRI).

Male Wistar rats underwent BRI, sham, or IPo surgery 24h and 1w after reperfusion. The rats’ explorative behaviors and motor function were evaluated by an open field, rotarod, and wire grip tests. The cognitive function was assessed by passive avoidance learning and Morris water maze tests. Western blotting was performed to evaluate hippocampal Brain-Derived Neurotrophic Factor (BDNF) expression.

The impairment of balance function induced by BRI was not reversed; however, passive avoidance learning impairment was reversed by postconditioning 24h after reperfusion. IPo increased muscle strength compared to the BRI group; however, explorative behaviors and balance function had no difference 1w after reperfusion. BRI significantly decreased the BDNF protein expression in the hippocampus, and postconditioning increased 24h after reperfusion.

The obtained results demonstrated the deleterious effect of BRI on cognitive and balance function 24h after reperfusion. IPo indicated a curative effect against cognitive dysfunction probably by enhancing BDNF protein expression in the hippocampus.

i-Maths is a new math educational program based on conceptualizing mathematical concepts for children aged 3-7 years. The early years of life are considered crucial for cognitive construct development and learning. Studies show that spatial working memory plays an important role in learning mathematics upon childhood. This study was an attempt to investigate whether a formal course of i-Maths training would potentially improve cognitive capacities such as short-term memory in children.

19 kids (7 girls and 12 boys, aged 5 to7 years) were randomly enrolled from an i-Maths training institute in Shiraz and stratified in two groups i.e. experienced and novice (n=10 in each group). The participants’ cognitive performance was measured using the Cambridge Neuropsychological Test Automated Battery (CANTAB). In addition, their hemodynamic response from the frontopolar brain region (FP1) was measured using the hemoencephalography (HEG) setup upon CANTAB task performance.

Subjects in both groups showed no significant difference in motor screening task (MOT) scores. Meanwhile, in the delayed matching to sample (DMS), there was significant difference in task scores in the experienced- as compared to the novice-group. The results of paired associates learning (PAL) shows significant difference in total number of errors (6 shapes adjusted) in the experienced- vs. novice-group. Nevertheless, the changes were not significant in terms of total errors (adjusted). Moreover, there was no significant change in HEG response in two groups.

It seems that learning mathematical concepts through i-Maths leaves favorable outcomes in distinct cognitive performance domains in young kids.

One of the most common causes of mortality in acute kidney injury is brain dysfunction. Here we investigated the possible protective effect of erythropoietin (EPO) on cognitive impairments induced by bilateral renal ischemia (BRI).
Eighty male Wistar rats were allocated into 8 groups: 1, 2) Sham (Vehicle), 3, 4) Shamჳ, 5, 6) BRI, 7, 8) BRIჳ. The groups followed by the reperfusion periods of 24hours (24h) and 1week (1w). EPO or saline was administrated 30 min before surgery (1000 IU/kg, i.p.). The cognitive function was assessed by passive avoidance learning and Morris water maze tests. Hippocampal brain-derived neurotrophic factor (BDNF) protein expression was assessed by western blotting.
BUN (blood urea nitrogen) and creatinine (Cr) concentrations were significantly increased in BRI group 24h after reperfusion. BRI rats had just an increased level of BUN but not Cr 1w after reperfusion. EPO reversed passive avoidance learning impairments observed in BRI group 24h after reperfusion. There were no significant differences in spatial and passive avoidance learning between experimental groups 1w after reperfusion and histological evaluation confirmed the behavioral data. BRI decreased significantly the BDNF protein expression in the hippocampus and EPO increased that 24h after operation.
These observations showed protective effect of EPO against cognitive dysfunctions following BRI 24h after reperfusion through increase in BDNF protein expression.

Dysregulated neuronal activity in Cortico-Striato-Thalamo-Cortical (CSTC) networks is primarily described as the pathophysiology of Tourette Syndrome (TS). New neuromodulation techniques including noninvasive transcranial Electrical Stimulation (tES) are increasingly considered among potential therapeutic options for TS. To test the therapy protocol with transcranial Direct Current Stimulation (tDCS) a 31 year-old male patient with TS was selected to be administered for 10 sessions over five days of bilateral cathodal tDCS (30 minutes, 2 mA) on C3 and FC5, while the anode electrodes were placed on FP2. Tic severity and frequency were subjectively reported by the subject following the treatment on weekly basis and treatment response was objectively assessed by two experts. The patient noted that he was able to control his unwanted movement after over one year follow-up. The current study results together with earlier reports support the therapeutic effects of cathodal tDCS on tics in patients with TS. Randomized sham-controlled studies are required to shed more light on such therapeutic impact and the optimized protocols.

Cerebral ischemic preconditioning lessens stroke-induced injuries, but it is clinically feasible only when the occurrence of stroke is predictable. Reperfusion plays a critical role against cerebral injury after stroke; we tested the hypothesis that interrupting ischemia during early reperfusion, i.e. Postconditioning (POCO) affects CXC chemokine expression and further reduce inflammation in rat model of ischemia/reperfusion. Materials & Adult male Wistar rats (250-300 g) were used in this experiment. Using 4-vessel occlusion method, global cerebral ischemia was induced and POCO was performed by applying 3 cycles of 15-s/15-s reperfusion/reocclusion after a 45-s reperfusion (POCO-45-15/15). Western blotting analysis was used to investigate CXCL1, CXCL10 and CXCL12 expression 24 h, 48 h and one week after ischemic postconditioning (iPOCO). Based on the results, iPOCO attenuates the expression of inflammatory chemokines CXCL1 and CXCL10 in hippocampus area of postconditioned rats, while the CXCL12 was not affected by iPOCO. Current findings may support chemokines role in iPOCO via reduction of inflammation. Also there could be a link between postconditioning, stress and inflammation through chemokines.

Dementia of Alzheimer Type (DAT) is associated with progressive cognitive impairments. Such a clinically significant condition is known to affect approximately 9.5% of people over 70 years of age. However, it is accepted as a more challengeable medical entity because of its increasing atypical presentation, rarity of efficient treatments, and diagnostic and prevention challenges.Materials & we present a case who referred with 5 months history of cognitive decline following Medial Temporal Lobe (MTL) atrophy upon neuroimaging. Following cognitive and neurophysiological assessments, she underwent 21 consecutive sessions of transcranial Direct Current Stimulation (tDCS) 3 times per week. Concurrently, a media-rich computer platform was administered for cognitive and behavioral remediation. Based on the evidence regarding the use of tDCS in dementia, we aimed at stabilizing the cognitive profile and halting or slowing down the process of progressive cognitive decline in the present case. The outcome of our neuromodulatory intervention using tDCS supported the beneficial impact of such an approach in not only stabilizing but also ameliorating cognitive functions. This is especially important when rapid progression of cognitive symptoms in DAT is of concern. The promising clinical course of this specific case supports the possible beneficial effects of tDCS in halting the progression of symptoms in DAT. Sham-controlled clinical trials would get momentum to highlight clinical impact of such an intervention in DAT.

Autism Spectrum Disorders (ASDs) are complex neurodevelopmental conditions with the characteristics including impairments in social interaction and communication, and restricted patterns of behaviors or interests. Lack of Theory of Mind (TOM), which is considered as the core concept of social interaction, was suggested as the underlying deficit of social, behavioral, and communicative impairments of ASD. Transcranial Direct Current Stimulation (tDCS), as a non-invasive brain stimulation technique, indicated promising results for the treatment of psychiatric disorders. The present methodology report aimed at proposing a design to study the possible effects of tDCS on TOM and cognitive empathy in ASD.

Over more than a century of research has demonstrated that sleep is necessary for the retention of memory. The current review aim to discuss the functional brain network connectivity is important during slow-wave sleep (SWS) for memory consolidation. While several evidences indicated the importance of SWS for memory consolidation but information to understand the main mechanisms of it are not enough.  Although there is the likely involvement of various factors in this phenomenon, we hypothesize the key role of Ih current arising memory consolidation during SWS by generation of neuronal oscillations. Finding the possible mechanism involving in this process may provide lights to suggesting new treatments against memory impairments.

There is evidence that exercise decreases ischemia/reperfusion injury in rats. Since behavioral deficits are the main outcome in patients after stroke, our study was designed to investigate whether exercise preconditioning improves the acute behavioral functions and also brain inflammatory injury following cerebral ischemia. Male rats weighing 250–300 g were randomly allocated into five experimental groups. Exercise was performed on a treadmill 30min/day for 3 weeks. Ischemia was induced by 4-vessel occlusion method. Recognition memory was assessed by novel object recognition task (NORT) and step-through passive avoidance task. Sensorimotor function and motor movements were evaluated by adhesive removal test and ledged beam-walking test, respectively. Brain inflammatory injury was evaluated by histological assessment. In NORT, the discrimination ratio was decreased after ischemia (P < 0.05) and exercise preconditioning improved it in ischemic animals. In the passive avoidance test, a significant reduction in response latency was observed in the ischemic group. Exercise preconditioning significantly decreased the response latency in the ischemic rats (P < 0.001). In the adhesive removal test, latency to touch and remove the sticky labels from forepaw was increased following induction of ischemia (all P < 0.001) and exercise preconditioning decreased these indices compared to the ischemic group (all P < 0.001). In the ledged beam-walking test, the slip ratio was increased following ischemia (P < 0.05). In the ischemia group, marked neuronal injury in hippocampus was observed. These neuropathological changes were attenuated by exercise preconditioning (P < 0.001). Our results showed that exercise preconditioning improves behavioral functions and maintains more viable cells in the dorsal hippocampus of the ischemic brain.