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1.
Cereb Cortex ; 33(22): 11157-11169, 2023 11 04.
Article in English | MEDLINE | ID: mdl-37757479

ABSTRACT

Precision walking (PW) incorporates precise step adjustments into regular walking patterns to navigate challenging surroundings. However, the brain processes involved in PW control, which encompass cortical regions and interregional interactions, are not fully understood. This study aimed to investigate the changes in regional activity and effective connectivity within the frontoparietal network associated with PW. Functional near-infrared spectroscopy data were recorded from adult subjects during treadmill walking tasks, including normal walking (NOR) and PW with visual cues, wherein the intercue distance was either fixed (FIX) or randomly varied (VAR) across steps. The superior parietal lobule (SPL), dorsal premotor area (PMd), supplementary motor area (SMA), and dorsolateral prefrontal cortex (dlPFC) were specifically targeted. The results revealed higher activities in SMA and left PMd, as well as left-to-right SPL connectivity, in VAR than in FIX. Activities in SMA and right dlPFC, along with dlPFC-to-SPL connectivity, were higher in VAR than in NOR. Overall, these findings provide insights into the roles of different brain regions and connectivity patterns within the frontoparietal network in facilitating gait control during PW, providing a useful baseline for further investigations into brain networks involved in locomotion.


Subject(s)
Brain Mapping , Cues , Adult , Humans , Walking , Brain , Spectroscopy, Near-Infrared
2.
Brain Behav ; 12(7): e2681, 2022 07.
Article in English | MEDLINE | ID: mdl-35701382

ABSTRACT

INTRODUCTION: Interacting with the environment requires the planning and execution of reach-to-target movements along given reach trajectory paths. Human neural mechanisms for the motor planning of linear, or point-to-point, reaching movements are relatively well studied. However, the corresponding representations for curved and more complex reaching movements require further investigation. Additionally, the visual and proprioceptive feedback of hand positioning can be spatially and sequentially coupled in alignment (e.g., directly reaching for an object), termed coupled visuomotor feedback, or spatially decoupled (e.g., dragging the computer mouse forward to move the cursor upward), termed decoupled visuomotor feedback. During reach planning, visuomotor processing routes may differ across feedback types. METHODS: We investigated the involvement of the frontoparietal regions, including the superior parietal lobule (SPL), dorsal premotor cortex (PMd), and dorsolateral prefrontal cortex (dlPFC), in curved reach planning under different feedback conditions. Participants engaged in two delayed-response reaching tasks with identical starting and target position sets but different reach trajectory paths (linear or curved) under two feedback conditions (coupled or decoupled). Neural responses in frontoparietal regions were analyzed using a combination of functional near-infrared spectroscopy and electroencephalography. RESULTS: The results revealed that, regarding the cue period, curved reach planning had a higher hemodynamic response in the left SPL and bilateral PMd and a smaller high-beta power in the left parietal regions than linear reach planning. Regarding the delay period, higher hemodynamic responses during curved reach planning were observed in the right dlPFC for decoupled feedback than those for coupled feedback. CONCLUSION: These findings suggest the crucial involvement of both SPL and PMd activities in trajectory-path processing for curved reach planning. Moreover, the dlPFC may be especially involved in the planning of curved reaching movements under decoupled feedback conditions. Thus, this study provides insight into the neural mechanisms underlying reaching function via different feedback conditions.


Subject(s)
Psychomotor Performance , Spectroscopy, Near-Infrared , Electroencephalography , Feedback , Humans , Movement/physiology , Parietal Lobe/diagnostic imaging , Parietal Lobe/physiology , Psychomotor Performance/physiology
3.
Front Neurorobot ; 16: 795079, 2022.
Article in English | MEDLINE | ID: mdl-35370598

ABSTRACT

Assistive exoskeleton robots are being widely applied in neurorehabilitation to improve upper-limb motor and somatosensory functions. During robot-assisted exercises, the central nervous system appears to highly attend to external information-processing (IP) to efficiently interact with robotic assistance. However, the neural mechanisms underlying this process remain unclear. The rostromedial prefrontal cortex (rmPFC) may be the core of the executive resource allocation that generates biases in the allocation of processing resources toward an external IP according to current behavioral demands. Here, we used functional near-infrared spectroscopy to investigate the cortical activation associated with executive resource allocation during a robot-assisted motor task. During data acquisition, participants performed a right-arm motor task using elbow flexion-extension movements in three different loading conditions: robotic assistive loading (ROB), resistive loading (RES), and non-loading (NON). Participants were asked to strive for kinematic consistency in their movements. A one-way repeated measures analysis of variance and general linear model-based methods were employed to examine task-related activity. We demonstrated that hemodynamic responses in the ventral and dorsal rmPFC were higher during ROB than during NON. Moreover, greater hemodynamic responses in the ventral rmPFC were observed during ROB than during RES. Increased activation in ventral and dorsal rmPFC subregions may be involved in the executive resource allocation that prioritizes external IP during human-robot interactions. In conclusion, these findings provide novel insights regarding the involvement of executive control during a robot-assisted motor task.

4.
J Physiol Sci ; 70(1): 42, 2020 Sep 16.
Article in English | MEDLINE | ID: mdl-32938363

ABSTRACT

Metabolic disorders can induce psychiatric comorbidities. Both brain and neuronal composition imbalances reportedly induce an anxiety-like phenotype. We hypothesized that alterations of localized brain areas and cholecystokinin (CCK) and parvalbumin (PV) expression could induce anxiety-like behavior in type 2 diabetic Otsuka Long-Evans Tokushima fatty (OLETF) rats. Twenty-week-old OLETF and non-diabetic Long-Evans Tokushima Otsuka (LETO) rats were used. The areas of corticolimbic regions were smaller in OLETF rats. The densities of CCK positive neurons in the lateral and basolateral amygdala, hippocampal cornu ammonis area 2, and prelimbic cortex were higher in OLETF rats. The densities of PV positive neurons were comparable between OLETF and LETO rats. Locomotion in the center zone in the open field test was lower in OLETF rats. These results suggest that imbalances of specific brain region areas and neuronal compositions in emotion-related areas increase the prevalence of anxiety-like behaviors in OLETF rats.


Subject(s)
Anxiety/etiology , Behavior, Animal , Brain/metabolism , Cholecystokinin/metabolism , Diabetes Mellitus, Type 2/complications , Neurons/metabolism , Animals , Anxiety/metabolism , Anxiety/physiopathology , Anxiety/psychology , Brain/physiopathology , Disease Models, Animal , Emotions , Locomotion , Male , Open Field Test , Parvalbumins/metabolism , Rats, Inbred OLETF
5.
Bioorg Med Chem Lett ; 28(23-24): 3741-3747, 2018 12 15.
Article in English | MEDLINE | ID: mdl-30337229

ABSTRACT

In this research several series of novel dioxygenated ring fused 4-anilinoquinazolines (10a-d) and 4-anilinoquinazoline-substituted triazole hybrid compounds (11-14) have been designed and synthesized. Their biological significance was highlighted by evaluating in vitro for anticancer activities, wherein several compounds displayed excellent activity specifically against three human cancer cell lines (KB, epidermoid carcinoma; HepG2, hepatoma carcinoma; SK-Lu-1, non-small lung cancer). Especially, compound 13a exhibited up to 100-fold higher cytotoxicity in comparison with erlotinib. Docking the most cytotoxic compounds (11d, 13a, 13b, and 14c) into the ATP binding site of different EGFR tyrosine kinase domains was perfomed to predict the analogous binding mode of these compounds to the EGFR targets.


Subject(s)
Aniline Compounds/chemistry , Aniline Compounds/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Drug Design , Quinazolines/chemistry , Quinazolines/pharmacology , Triazoles/chemistry , Triazoles/pharmacology , Amino Acid Sequence , Aniline Compounds/chemical synthesis , Antineoplastic Agents/chemical synthesis , Cell Line, Tumor , Drug Screening Assays, Antitumor , ErbB Receptors/chemistry , ErbB Receptors/metabolism , Humans , Molecular Docking Simulation , Neoplasms/drug therapy , Neoplasms/metabolism , Quinazolines/chemical synthesis , Sequence Alignment , Structure-Activity Relationship , Triazoles/chemical synthesis
6.
J Environ Sci (China) ; 17(2): 194-9, 2005.
Article in English | MEDLINE | ID: mdl-16295887

ABSTRACT

The new turning method was proposed and verified its effectiveness to pathogens by laboratory scale experiments. Considering the results obtained from the previous studies, it could be said that turning of a composting pile was essential in terms of hygienic aspects but the number of turning should be minimized. Effectiveness of inactivation was estimated for each composting run. From this estimation, turning by layers, which is different from conventional turning that mixes compost pile entirely, was proposed and investigated its performance by experiments. Composting operations with static pile method, complete mix (conventional) turning method, and proposed turning (layer turning) method were done and their effectiveness on inactivation of indicator microorganism was evaluated and compared. As results, the conventional turning method was not a proper method in terms of pathogen inactivation, whereas, the proposed turning method showed an excellent performance and should be employed in a composting operation.


Subject(s)
Bacteria/growth & development , Refuse Disposal/methods , Soil Microbiology , Soil/analysis , Temperature , Bacteria/pathogenicity , Occupational Health
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