Impact of Zinc Oxide on the Development of Aspergillus-Induced Maxillary Sinusitis Rabbit Model.

Aspergillus fumigatus is commonly found in the airway and is associated with airway inflammatory diseases. Zinc oxide (ZO) is known to be an essential microelement that facilitates fungal survival, growth, and proliferation. This study aimed to investigate the impact of ZO on A. fumigatus-induced fungal sinusitis in rabbits. Twenty-eight New Zealand white rabbits were divided into four groups for this study. Group 1 (6 sides) was treated with intramaxillary phosphate buffer saline (PBS) served as the negative control, Group 2 (6 sides) received intramaxillary PBS and ZO, Group 3 (8 sides) was treated with intramaxillary A. fumigatus alone, and Group 4 (8 sides) treated with intramaxillary A. fumigatus with ZO. After 4 and 12 weeks, sinus mucosal cytokine and transcription factor expressions were determined. A histological analysis was performed to determine inflammatory cell infiltration, number of secretory cells, and mucosal thickness. Fungal biofilm formation was determined using confocal laser microscopy. The intramaxillary instillation of A. fumigatus conidia led to an increase in protein and mRNA expression of interleukin (IL)-1ß and IL-8 in the maxillary sinus mucosa. They were associated with mitogen-activated protein kinase and activator protein-1. Furthermore, intramaxillary instillation of fungal conidia resulted in significant enhancement of inflammatory cell infiltration, epithelial thickening, and fungal biofilm formation. However, intramaxillary ZO did not have a significant impact on A. fumigatus-induced cytokine protein and mRNA expression, and inflammatory cell infiltration and epithelial thickness in sinonasal mucosa. While intramaxillary instillation of A. fumigatus increased mucosal inflammation, cytokine production, and biofilm formation, the intramaxillary application of ZO did not have a significant influence on inflammation in the maxillary sinus mucosa.

Changes in the BOLD signal of S1 and BA3 per finger/phalanx as a response to high-frequency vibratory stimulation.

PURPOSE AND METHOD: The purpose of this study was to determine the changes in the Blood Oxygen Level Dependent signal of Primary somatosensory area (S1) and Brodmann area 3 (BA3) per finger and phalanx in comparison to the activation voxel when 250 Hz vibratory stimulation with high sensitivity for the Pacinian corpuscle was given to the four fingers and three phalanges. RESULTS: The result of analyzing the activation voxel showed a significant difference for S1 per finger and phalanx, but for BA3, no significant difference was observed despite a similar trend to S1. In contrast, the activation intensity (BOLD) displayed a significant difference for S1 per finger and phalanx and for BA3, where the activation voxel had no significant variation. In addition, while the result of S1 did not indicate whether the index or the little fingers had the highest sensitivity based on the BOLD signal per finger, the result of BA3 marked the strongest BOLD signal for the little finger as a response to 250 Hz vibratory stimulation. The activation intensity per phalanx was the highest for the intermediate phalanx for S1 and BA3, which was in line with a previous study comparing the activation voxel. CONCLUSIONS: The method based on the intensity of the nerve activation is presumed to have high sensitivity as the signal intensity is monitored within a specific, defined area. Thus, for the extraction of brain activation patterns of micro-domains, such as BA3, monitoring the BOLD signal that reflects the nerve activation intensity more sensitively is likely to be advantageous.

Aspergillus Enhances Eosinophil and Neutrophil Extracellular DNA Trap Formation in Chronic Rhinosinusitis.

Chronic rhinosinusitis (CRS) is characterized by inflammatory cell infiltration in the sinonasal mucosa. Eosinophil and neutrophil extracellular traps (EETs and NETs, respectively) are prominently found in CRS. This study aimed to investigate the effect of airborne fungi, Alternaria alternata and Aspergillus fumigatus, on EET and NET formation. Nasal epithelial cells, eosinophils, and neutrophils were isolated from eosinophilic CRS (ECRS), non-ECRS (NECRS), and healthy control. We determined eosinophil and neutrophil transepithelial migration after fungal treatment. We then determined the release of EETs and NETs by fungi using Sytox Green staining and determined the role of reactive oxygen species (ROS) using ROS inhibitors. We identified more abundant EETs and NETs in ECRS than in NECRS. A. alternata and A. fumigatus enhanced eosinophil and neutrophil transepithelial migration. A. fumigatus strongly induced EET and NET formation in CRS and, simultaneously, suppressed fungal metabolic activity. EET formation in CRS is associated with nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase and NET formation with NADPH-oxidase and mitochondrial ROS. A. fumigatus, but not A. alternata, induced EET and NET formation, and peripheral blood eosinophils and neutrophils exhibited different immune responses against A. fumigatus following the inflammatory status of the host. Aspergillus-fumigatus-induced EET and NET formation plays a crucial role in CRS pathogenesis.

The use of natural language to communicate the perception of vibrotactile stimuli.

This study explores the subjective use of adjectives to verbally communicate vibrotactile stimulation across multiple frequencies. In total, nine different vibrotactile stimulus frequencies (10-300 Hz) were utilized, and subjective evaluation methods, which involved adjectives, were used to assess the sensory representations of the participants (18 healthy male participants; mean age, 22.9 years; standard deviation, 3.5). Sensory terms such as 'slow,' 'protruding,' and 'thick' were used as representative expressions to describe low-frequency (10-100 Hz) vibrotactile stimulations, while 'fast,' 'shallow,' and 'tickly' were used to describe high-frequency (225-300 Hz) vibrotactile stimulations. At the frequencies of 150 and 200 Hz, no characteristic word was found because there was no difference in subjective evaluation scores from other low or high frequencies. The results suggest that vibrotactile stimulation at different frequencies induce diverse sensory representations, owing to not only the motion and shape of the stimuli but also the subjective responses of the perceivers. The results of this study could be utilized in developing affective haptic devices in the future.

Hypomyelination and cognitive impairment in mice lacking CD133 (Prominin-1).

The CD133 antigen, also known as prominin-1, is a glycoprotein that specifically localizes to plasma membrane protrusions. The precise function of CD133 remains unknown, but it is expressed in various progenitor cells including those derived from the neural and hematopoietic system, as well as different tissues. In the adult mouse brain, CD133 is highly expressed in white matter. Here, we performed immunohistochemical staining and electron microscopy to demonstrate that mice lacking CD133 (CD133-/-) exhibit decreased myelin in the corpus callosum, the largest white matter tract in the brain. Hypomyelination in CD133-/- mice was associated with fewer oligodendrocyte progenitor cells and mature oligodendrocytes. Behavioral analyses revealed that significantly impaired object recognition memory and altered Y-maze performance by CD133-/- mice compared with wild-type mice, suggesting perturbed cognitive performance. These results suggest that CD133 regulates myelination and understanding the underlying molecular mechanisms may guide the development of novel therapeutic strategies for diseases characterized by myelin deficiency.

Development of a puff- and suction-type pressure stimulator for human tactile studies.

In this study, we developed a tactile stimulator capable of administering either puff- or suction-type stimuli. The system is composed of three parts: a control unit, an air-handling unit, and a stimulation unit. The control unit controls the type, intensity, and time of stimulation. The air-handling unit delivers the stimulation power quantitatively to the stimulation unit, as commanded by the control unit. The stimulation unit stably administers either type of pressure to the skin, without any change of the tactor. Although the design of the stimulator is simple, it allows for five levels of control of the stimulation intensity (2-6 psi) and 0.1-s steps of control of the stimulation time, as we confirmed by tests. Preliminary electroencephalographic and event-related potential (ERP) studies of our system in humans confirmed the presence of N100 and P300 waves at standard electrode position C3, which are related to perception and cognition, respectively, in the somatosensory area of the brain. In addition, different stimulation types (puff and suction) and intensities (2 and 6 psi) were reflected in different peak-to-peak amplitudes and slopes of the mean ERP signal. The system developed in this study is expected to contribute to human tactile studies by providing the ability to administer puff- or suction-type stimuli interchangeably.

Differences in and correlations between cognitive abilities and brain volumes in healthy control, mild cognitive impairment, and Alzheimer disease groups.

The purpose of this study is to investigate differences in and correlations between cognitive abilities and brain volumes in healthy control (HC), mild cognitive impairment (MCI), and Alzheimer's disease (AD) groups. The Korean Version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K), which is used to diagnose AD, was used to measure the cognitive abilities of the study subjects, and the volumes of typical brain components related to AD diagnosis-cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM)-were acquired. Of the CERAD-K subtests, the Boston Naming Test distinguished significantly among the HC, MCI, and AD groups. GM and WM volumes differed significantly among the three groups. There was a significant positive correlation between Boston Naming Test scores and GM and WM volumes. In conclusion, the Boston Naming Test and GM and WM brain volumes differentiated the three tested groups accurately, and there were strong correlations between Boston Naming Test scores and GM and WM volumes. These results will help to establish a test method that differentiates the three groups accurately and is economically feasible.

Primary and secondary gait deviations of stroke survivors and their association with gait performance.

[Purpose] Stroke survivors exhibit abnormal pelvic motion and significantly deteriorated gait performance. Although the gait of stroke survivors has been evaluated at the primary level pertaining to ankle, knee, and hip motions, secondary deviations involving the pelvic motions are strongly related to the primary level. Therefore, the aim of this study was to identify the kinematic differences of the primary and secondary joints and to identify mechanism differences that alter the gait performance of stroke survivors. [Subjects and Methods] Five healthy subjects and five stroke survivors were recruited. All the subjects were instructed to walk at a self-selected speed. The joint kinematics and gait parameters were calculated. [Results] For the stroke survivors, the range of motion of the primary-joint motions were significantly reduced, and the secondary-joint motions were significantly increased. Additionally, for the healthy subjects, the primary joint kinematics were the main factors ensuring gait performance, whereas for the stoke survivors, the secondary-joint motions were the main factors. [Conclusion] The results indicate that while increasing the range of motion of primary-joint movements is the main target to achieve, there is a strong need to constrain and support pelvic motions in order to improve the outcome of gait rehabilitation.

Differences in driving performance due to headway distances and gender: the application of jerk cost function.

Driving is directly controlled by the driver's movement. This study tried to compare differences in gender and headway distances between the DRIVING phase and the SUDDEN STOP phase by using subjects' movement during driving in the simulator. To quantify subjects' movement, the jerk cost function (JC) was used, and conventional vehicle control parameters such as the coefficient of variation of the mediolateral trajectory (MLCV) for lane keeping and the brake time (BT) were also used. As the headway distance increased, MLCV and JC decreased significantly in the DRIVING phase. In the SUDDEN STOP phase, BT was increased and, MLCV and JC were decreased. Differences between genders were detected for both MLCV (males < females) and JC (males > females). The results of this study demonstrate that JC may be used as a variable in evaluating driving performance as influenced by driving conditions and gender.

Development of a simple pressure and heat stimulator for intra- and interdigit functional magnetic resonance imaging.

For this study, we developed a simple pressure and heat stimulator that can quantitatively control pressure and provide heat stimulation to intra- and interdigit areas. The developed stimulator consists of a control unit, drive units, and tactors. The control unit controls the stimulation parameters, such as stimulation types, intensity, time, and channel, and transmits a created signal of stimulation to the drive units. The drive units operate pressure and heat tactors in response to commands from the control unit. The pressure and heat tactors can display various stimulation intensities quantitatively, apply stimulation continuously, and adjust the stimulation areas. Additionally, they can easily be attached to and detached from the digits. The developed pressure and heat stimulator is small in total size, easy to install, and inexpensive to manufacture. The new stimulator operated stably in a magnetic resonance imaging (MRI) environment without affecting the obtained images. A preliminary functional magnetic resonance imaging (fMRI) experiment confirmed that differences in activation of somatosensory areas were induced from the pressure and heat stimulation. The developed pressure and heat stimulator is expected to be utilized for future intra- and interdigit fMRI studies on pressure and heat stimulation.

Development of a simple MR-compatible vibrotactile stimulator using a planar-coil-type actuator.

For this study, we developed a magnetic resonance (MR)-compatible vibrotactile stimulator using a planar-coil-type actuator. The newly developed vibrotactile stimulator consists of three units: control unit, drive unit, and planar-coil-type actuator. The control unit controls frequency, intensity, time, and channel, and transfers the stimulation signals to the drive unit. The drive unit operates the planar-coil-type actuator in response to commands from the control unit. The planar-coil-type actuator, which uses a planar coil instead of conventional electric wire, generates vibrating stimulation through interaction of the current of the planar coil with the static magnetic field of the MR scanner. Even though the developed tactile stimulating system is small, simple, and inexpensive, it has a wide range of stimulation frequencies (20 ~ 400 Hz, at 40 levels) and stimulation intensities (0 ~ 7 V, at 256 levels). The stimulation intensity does not change due to frequency changes. Since the transient response time is a few microseconds, the stimulation time can be controlled on a scale of microseconds. In addition, this actuator has the advantages of providing highly repeatable stimulation, being durable, being able to assume various shapes, and having an adjustable contact area with the skin. The new stimulator operated stably in an MR environment without affecting the MR images. Using functional magnetic resonance imaging, we observed the brain activation changes resulting from stimulation frequency and intensity changes.

Driving performance changes of middle-aged experienced taxi drivers due to distraction tasks during unexpected situations.

This study investigated the effects of distraction taskssuch as sending a text message with a cellphone and searching navigation with car navigation system-on the driving performance of 29 highly experienced taxi drivers in their 50s. All participants were instructed to drive using a driving simulator for 2 min. while maintaining a constant distance from the vehicle in front and a constant speed. Participants drove without any distractions for the first minute. For an additional minute, they performed Driving Only or performed a task while driving (Driving + Sending Text Message or Driving + Searching Navigation). An unexpected situation, in which the participant had to stop abruptly due to a sudden stop of the preceding vehicle, occurred during this period. Driving performance during the unexpected situation was evaluated by car control variables, medial-lateral coefficient of variation and brake time, and by motion variables such as the jerk-cost function. Compared to Driving Only, jerk-cost function, medial-lateral coefficient of variation, and brake time increased during Driving + Sending Text Message or Driving + Searching Navigation.

A Pilot Study: Extraction of a Neural Network and Feature Extraction of Generation and Reduction Mechanisms Due to Acute Stress.

This study aimed to compare the functional connectivity (FC) assessed during acute stress and recovery after stress using the Montreal imaging stress task (MIST) in adults in their 20s and 30s with Korean Perceived Stress Scale (PSS) scores between 15 and 19 points inclusive. Four seed networks, including the salience network, default mode network, frontoparietal network, and dorsal attention network, were specified to extract the results. Healthy male and female adults who were required to make an effort to relieve stress were exposed to acute stress tasks, and the most common FCs were observed in the salience network, default mode network, and frontoparietal network during the stress and recovery phases. Compared to the stress phase, the increased effect size was significantly different in the recovery phase. In the stress phase, characteristically common FCs were observed in the dorsal attention network. During the recovery period, Salience network (Anterior Insula, R) and Salience network (anterior cingulate cortex, ACC)/Salience network (rostral prefrontal cortex, RPFC), Salience network (AInsula) and Salience network (RPFC), and Default Mode network (posterior cingulate) cortex, PCC) and fronto-parietal network (lateral prefrontal cortex, LPFC) FC were characteristically observed.

Development and validation of a computational method to predict unintended auditory brainstem response during transcranial ultrasound neuromodulation in mice.

BACKGROUND: Transcranial ultrasound stimulation (TUS) is a promising noninvasive neuromodulation modality. The inadvertent and unpredictable activation of the auditory system in response to TUS obfuscates the interpretation of non-auditory neuromodulatory responses. OBJECTIVE: The objective was to develop and validate a computational metric to quantify the susceptibility to unintended auditory brainstem response (ABR) in mice premised on time frequency analyses of TUS signals and auditory sensitivity. METHODS: Ultrasound pulses with varying amplitudes, pulse repetition frequencies (PRFs), envelope smoothing profiles, and sinusoidal modulation frequencies were selected. Each pulse's time-varying frequency spectrum was differentiated across time, weighted by the mouse hearing sensitivity, then summed across frequencies. The resulting time-varying function, computationally predicting the ABR, was validated against experimental ABR in mice during TUS with the corresponding pulse. RESULTS: There was a significant correlation between experimental ABRs and the computational predictions for 19 TUS signals (R2 = 0.97). CONCLUSIONS: To reduce ABR in mice during in vivo TUS studies, 1) reduce the amplitude of a rectangular continuous wave envelope, 2) increase the rise/fall times of a smoothed continuous wave envelope, and/or 3) change the PRF and/or duty cycle of a rectangular or sinusoidal pulsed wave to reduce the gap between pulses and increase the rise/fall time of the overall envelope. This metric can aid researchers performing in vivo mouse studies in selecting TUS signal parameters that minimize unintended ABR. The methods for developing this metric can be adapted to other animal models.

Study on the Cognitive Characteristics Induced by Changes in the Intensity, Frequency and Duration of Vibratory Stimuli.

The purpose of this study is to analyze the cognitive characteristics that can be induced by vibration stimuli at two intensities, three frequencies, and five presentation periods. The experiment was conducted on 20 right-handed adult males, and a subjective evaluation was performed using a questionnaire. Regression analysis was performed to observe the parameters affecting cognitive characteristics according to changes in intensity, frequency, and stimulation duration. The regression analysis results showed that the cognitive characteristics affected by changes in intensity, frequency, and stimulation duration were "heavy", "bold", "thick", and "light". The cognitive characteristics affected by two-variable combinations were "deep", "clear", "vibrating", "dense", "numb", "blunt", "shallow", "fuzzy", and "soft". Cognitive characteristics affected by either intensity, frequency, or stimulation duration were "fast", "pungent", "skinny", "thin", "slow", "ticklish", "tingling", "prickling", "tap", and "rugged". By observing the cognitive characteristics that can be induced by the combination of intensity, frequency, and stimulation duration, we confirmed that in addition to intensity and frequency, the stimulation duration is an important factor that influences the induction of various cognitive characteristics. The results presented in the study can be used to enhance the utility of haptic surfaces for extended reality applications.

Effects of inaudible binaural beats on visuospatial memory.

OBJECTIVES: Binaural beats are auditory beat stimulation that produces sounds and induces a specific state of brain wave based on the difference in the frequency of stimulation. This study aimed to investigate the effects of inaudible binaural beats on visuospatial memory at 18 000 Hz reference and 10 Hz difference frequencies. METHODS: Eighteen adult subjects in their twenties were enrolled, including 12 males (mean age: 23.8 ±â€…1.2) and 6 females (mean age: 22.8 ±â€…0.8). An auditory stimulator providing 10 Hz binaural beats stimulation via 18 000 Hz to the left and 18 010 Hz to the right ears was used. The experiment consisted of two 5-min phases, including a rest phase and a task phase involving task performance without (Task-only) and with binaural beats stimulation (Task+BB). A 3-back task was used to measure visuospatial memory. Cognitive ability measured by task performance (accuracy and reaction time) with and without binaural beats, as well as variations in alpha power across different brain domains, were compared using paired t-tests. RESULTS: Compared to the Task-only condition, the Task+BB condition had significantly higher accuracy and significantly shorter reaction time. The electroencephalogram analysis showed that the reduction level in alpha power for the task performance under the Task+BB condition was significantly lower in all brain areas except the frontal, compared to that under the Task-only condition. CONCLUSION: The significance of this study lies in having verified the independent effects of binaural beats stimulation without any auditory influence, based on visuospatial memory.

Measuring sound velocity based on acoustic resonance using multiple narrow band transducers.

The sound velocity in a medium is closely related to its material properties, including its composition, structure, density, pressure, and temperature. Various methods have been developed to determine the sound velocity through materials. Among them, a strategy based on ultrasound resonance frequency has been most widely used due to the simplicity. However, it requires a transducer with a wide bandwidth to cover enough resonance frequencies to perform the consequent calculations. In this paper, we develop a resonance method for measuring sound velocity, using multi-frequency narrow-band transducers breaking through the limitation of transducer bandwidth on the utilization of the resonance method. We use different transducers at different center frequencies and with different bandwidth to measure the sound velocity in 100-µm and 400-µm thick steel pieces. The measurement results of different combinations are in good agreement, verifying that the use of multi-frequency narrow-band transducer combinations. Given that most therapeutic transducers have a narrow bandwidth, this method can be used during intracranial ultrasound stimulation to optimize targeting by non-invasively measuring the sound velocity in the skull, especially at thinner locations.

Frequency-following response effect according to gender using a 10-Hz binaural beat stimulation.

BACKGROUND: Several studies have continuously investigated FFRs using binaural beat (BB) stimulations and their related effects. However, only a few studies have investigated the differences in BB stimulation effects according to basic demographic characteristics, such as gender and age. OBJECTIVE: This study aimed to determine the alpha wave activity after a 10-Hz BB stimulation and subsequently identify differences according to gender across all brain areas (frontal, central, parietal, temporal, and occipital areas). METHODS: A total of 23 healthy adults (11 male and 12 female), aged 20-29, participated in the study. For the 10-Hz BB stimulation, pure tone auditory stimuli of 250 and 260 Hz were given to the left and right ear, respectively. Through a power spectrum analysis of the phase-excluding BBs (non-BBs) and phase-including 10-Hz BBs (α-BBs), the alpha power at each brain area was estimated. These values were compared using a mixed-design ANOVA. RESULTS: With the exception of the temporal area, all other brain areas showed a significant increase in alpha power for α-BBs compared to those of non-BBs. However, the difference according to gender was not significant. CONCLUSION: The results indicated the lack of gender effects in alpha wave generation through a 10-Hz BB stimulation.

Wnt5a-dopamine D2 receptor interactions regulate dopamine neuron development via extracellular signal-regulated kinase (ERK) activation.

The dopamine D2 receptor (D2R) plays an important role in mesencephalic dopaminergic neuronal development, particularly coupled with extracellular signal-regulated kinase (ERK) activation. Wnt5a protein is known to regulate the development of dopaminergic neurons. We analyzed the effect of Wnt5a on dopaminergic neuron development in mesencephalic primary cultures from wild-type (WT) and D2R knock-out (D2R(-/-)) mice. Treatment with Wnt5a increased the number and neuritic length of dopamine neurons in primary mesencephalic neuronal cultures from WT mice, but not from D2R(-/-) mice. The effect of Wnt5a was completely blocked by treatment with D2R antagonist or inhibitors of MAPK or EGFR. Wnt5a-mediated ERK activation in mesencephalic neuronal cultures was inhibited by treatment of D2R antagonist and EGFR inhibitors in WT mice. However, these regulations were not observed for D2R(-/-) mice. Co-immunoprecipitation and displacement of [(3)H]spiperone from D2R by Wnt5a demonstrated that Wnt5a could bind with D2R. This interaction was confirmed by GST pulldown assays demonstrating that the domain including transmembrane domain 4, second extracellular loop, and transmembrane domain 5 of D2R binds to Wnt5a. These results suggest that the interaction between D2R and Wnt5a has an important role in dopamine neuron development in association with EGFR and the ERK pathway.

A study on orbital volume of Korean people in their 20s or 40s.

AIMS: To measure the orbital volume of normal Korean people in two different age groups (subjects were in their 20s or 40s), and analyze the differences of orbital volume with respect to age and gender. In addition, to analyze correlation between body parameters (height and weight) and the orbital volume. METHODS: Magnetic resonance imaging (MRI) data were acquired for a total of 143 subjects, consisting of 71 subjects in their 20s (32 males and 39 females) and 72 subjects in their 40s (30 males and 42 females). Two-way ANOVA was used to analyze how orbital volume changes with respect to gender and age. A multiple regression analysis was performed to investigate the correlation between body parameters and the orbital volume. RESULTS: The orbital volume of subjects in their 20s was larger than that of subjects in their 40s, and the volume was larger in men than in women. As age increased, the decrease in the orbital volume of women was greater than that of men. While weight and height showed positive correlations with orbital volume in male and female subjects in their 20s, respectively, weight showed a positive correlation with orbital volume in male and female subjects in their 40s. CONCLUSIONS: These results provide basic information about the effect of age, gender, and body parameters on orbital volume of Korean people in their 20s or 40s.