• Physical Therapy Rehabilitation Science
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• v.13 no.2
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• pp.213-222
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• 2024

Objective: Stroke is a leading cause of disability worldwide, often leaving survivors with significant cognitive and motor impairments. Dual-task (DT), which involves performing cognitive and motor tasks simultaneously, can influence brain activation patterns and functional recovery in stroke patients. Design: A systematic review Methods: Following PRISMA guidelines, databases including MEDLINE, CINAHL, Embase, and Web of Science were searched for studies assessing cortical activation via functional near-infrared spectroscopy (fNIRS) during DT performance in stroke patients. Studies were selected based on predefined eligibility criteria, focusing on changes in hemodynamic responses and their correlation with task performance. Results: Eight studies met the inclusion criteria. Findings indicate that DT leads to increased activation in the prefrontal cortex (PFC), premotor cortex (PMC), and posterior parietal cortex (PPC), suggesting an integrated cortical response to managing concurrent cognitive and motor demands. However, increased activation did not consistently translate to improved functional outcomes, highlighting the complex relationship between brain activation and rehabilitation success. Conclusions: DT interventions may enhance cortical activation and neuroplasticity in post-stroke patients, but the relationship between increased brain activity and functional recovery remains complex and requires further investigation. Tailored DT programs that consider individual neurophysiological and functional capacities are recommended to optimize rehabilitation outcomes.

• Proceedings of the KSMRM Conference
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• 2001.11a
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• pp.105-105
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• 2001

Purpose： The activation of the Brocas and the Wernickes area in the language functional MR (fMR) well-known phenomena. We want to evaluate correlation of that activation with langua lateralization. So we evaluate the lateralization using the activation of the Brocas and t Wernickes area comparing with total cortical activation amount of cerebral hemisphere in t functional MR for measuring language lateralization based on Wada test.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.2
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• pp.41-51
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• 2019

PURPOSE: This study was conducted to investigate the effects of combined Joint Mobilization and Functional Electrical Stimulation on Muscle Activation and Mobility of ankle joints in stroke patients and their Modified Functional Reach Test (MFRT) results. METHODS: A total of 26 patients with stroke were randomly selected for enrollment in this study. (1) Functional Electrical Stimulation (FES) (2) combined Joint Mobilization and FES. An EMG system was used to measure tibialis anterior and gastrocnemius activities. Range Of Motion (ROM) of Ankle Joint and MFRT for Dynamic Balance. Pre and post intervention results were compared by paired-t-tests and differences in changes after intervention between groups were identified by the independent t-test. RESULTS: The muscle activation, ROM, and MFRT differed significantly in the experimental group (p<.05). The ROM was significantly different for the active dorsiflexion pre and post intervention in the group that received FES alone (p<.05). CONCLUSION: The results of this study suggest use of a systematic program of proactive posture control to prevent dysfunction when planning interventions for ankle joints can help stroke patients walk efficiently.

• Journal of Korean Neurosurgical Society
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• v.50 no.3
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• pp.209-215
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• 2011

Objective : The authors investigated the changes of cortical sensorimotor activity in functional MRI (fMRI) and functional recovery in spinal cord injury (SCI) patients who had been treated by bone marrow cell transplantation. Methods : Nineteen patients with SCI were included in this study; ten patients with clinical improvement and nine without. The cortical sensorimotor activations were studied using the proprioceptive stimulation during the fMRI. Results : Diagnostic accuracy of fMRI with neurological improvement was 70.0% and 44.4% for sensitivity and specificity, respectively. Signal activation in the ipsilateral motor cortex in fMRI was commonly observed in the clinically neurological improved group (p-value=0.002). Signal activation in the contralateral temporal lobe and basal ganglia was more commonly found in the neurological unimproved group (p-value<0.001). Signal activation in other locations was not statistically different. Conclusion : In patients with SCI, activation patterns of fMRI between patients with neurologic recovery and those without varied. Such plasticity should be considered in evaluating SCI interventions based on behavioral and neurological measurements.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3405-3409
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• 2013

The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.656-658
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• 1999

This paper presents musculotendon model to show the decline in muscle force during functional electrical stimulation (FES). It represent muscle activation and contraction concepts including muscle fatigue. A muscle fatigue term in activation dynamics as a function of the intracellular acidification and the pulsewidth of stimulation pulses change activation to decline muscle force. The computer simulation shows that muscle force decline in stimulation time.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.208-208
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• 1996

In this work we investigated coupling of the m2 and m4 subtypes of muscarinic acetylcholine receptors expressed in chinese hamster ovary (CHO) cells to activation of neuronal nitric oxide synthase (nNOS). Stimulation of guanylate cyclase activity in detector neuroblastoma cells was used as an index of generation of nitric oxide (NO) in CHO cells. The agonist carbachol induced marked time and concentration-dependent enhancement of the activity of nNOS at m2 receptors. In sharp contrast, the response in CHO cells transfected with the m4 receptor gene was similar in magnitude to that observed in non-transfected cells, suggesting lack of significant coupling of m4 muscarinic receptors to NO signaling. This novel observation of functional divergence of the two muscarinic receptor subtypes at the level of activation of nNOS is quite intriguing, in light of the currently accepted dogma that they belong to the same functional class. This functional selectivity was not due to differential effects on intracellular Ca$\^$2+/ concentration, since activation of both subtypes of muscarinic receptors produced a comparable, albeit quite small, Ca$\^$2+/ signal. Taken together, our present data strongly suggest that the generally assumed functional equivalence of m2 and m4 muscarinic receptors should be carefully reexamined. These data also suggest the presence of alternate mechanisms of activation of nNOS, which might be operative in the absence of large changes in the concentration of cellular Ca$\^$2+/. The latter mechanisms are expected to be activated by m2, but not m4 muscarinic receptors. Both sets of findings are quits important in regards to refining the functional classification of muscarinic receptor subtypes and the cellular mechanisms of activation of NOS.

• Investigative Magnetic Resonance Imaging
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• v.10 no.1
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• pp.26-31
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• 2006

Purpose : To evaluate the effect of global scaling analysis on brain activation for sensory and motor functional MR imaging study. Materials and methods : Four normal subjects without abnormal neurological history were included. Arm extension-flexion movement was used for motor function and 1KHz pure tone stimulation was used for auditory function. Functional magnetic resonance imaging was performed at 3T MRI (GE, Milwaukee, USA) using BOLD-EPI technique and SPM2 was employed for data analysis. On data analysis, the brain activation images were obtained with and without global scaling by fixing other parameters such as motion correction and realignment. Results : The difference in brain activation between no scaling and global scaling was not large in case of right upper extremity movement (p<0.000001). For auditory test, brain activation with global scaling showed larger activation than that of without global scaling (p<0.05). Conclusion : A caution must be taken into account when analyzing functional imaging data with global scaling especially for functional study of small local BOLD signal change.

• Biomolecules & Therapeutics
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• v.30 no.1
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• pp.55-63
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• 2022

Oleanolic acid (OA), a natural pentacyclic triterpenoid, has been reported to exert protective effects against several neurological diseases through its anti-oxidative and anti-inflammatory activities. The goal of the present study was to evaluate the therapeutic potential of OA against acute and chronic brain injuries after ischemic stroke using a mouse model of transient middle cerebral artery occlusion (tMCAO, MCAO/reperfusion). OA administration immediately after reperfusion significantly attenuated acute brain injuries including brain infarction, functional neurological deficits, and neuronal apoptosis. Moreover, delayed administration of OA (at 3 h after reperfusion) attenuated brain infarction and improved functional neurological deficits during the acute phase. Such neuroprotective effects were associated with attenuation of microglial activation and lipid peroxidation in the injured brain after the tMCAO challenge. OA also attenuated NLRP3 inflammasome activation in activated microglia during the acute phase. In addition, daily administration of OA for 7 days starting from either immediately after reperfusion or 1 day after reperfusion significantly improved functional neurological deficits and attenuated brain tissue loss up to 21 days after the tMCAO challenge; these findings supported therapeutic effects of OA against ischemic stroke-induced chronic brain injury. Together, these findings showed that OA exerted neuroprotective effects against both acute and chronic brain injuries after tMCAO challenge, suggesting that OA is a potential therapeutic agent to treat ischemic stroke.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.4
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• pp.471-478
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• 2005

The objective of this research is to improve adsorption efficiency of adsorbent made from MSWI (Municipal Solid Waste Incinerator) ny ash by $HNO_3$ activation. The acidity and the basicity were determined by Boehm's method and the surface structure was studied by BET method with N2 adsorption. The adsorption properties were investigated with benzene and MEK (Methylethylketone). $HNO_3$ activation can modify the surface property of an adsorbent such as specific surface area, pore volume, and functional group. According to the results, the specific surface area of the adsorbent was increased from $309.2m^2/g\;to\;553.2 m^2/g$ by activation. Also oxygen-containing functional groups were formed on it.