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1.
Mycobiology ; : 302-316, 2022.
Article in English | WPRIM | ID: wpr-968383

ABSTRACT

Many Apiospora species have been isolated from bamboo plants – to date, 34 bambusicolous Apiospora species have been recorded. They are known as saprophytes, endophytes, and plant pathogens. In this study, 242 bambusicolous Apiospora were isolated from various bamboo materials (branches, culms, leaves, roots, and shoots) and examined using DNA sequence similarity based on the internal transcribed spacer, 28S large subunit ribosomal RNA gene, translation elongation factor 1-alpha, and beta-tubulin regions. Nine Apiospora species (Ap. arundinis, Ap. camelliae-sinensis, Ap. hysterina, Ap. lageniformis sp. nov., Ap. paraphaeosperma, Ap. pseudohyphopodii sp. nov., Ap. rasikravindrae, Ap. saccharicola, and Ap. sargassi) were identified via molecular analysis. Moreover, the highest diversity of Apiospora was found in culms, and the most abundant species was Ap. arundinis. Among the nine Apiospora species, two (Ap. hysterina and Ap. paraphaeosperma) were unrecorded in Korea, and the other two species (Ap. lageniformis sp. nov. and Ap. pseudohyphopodii

2.
Mycobiology ; : 46-54, 2022.
Article in English | WPRIM | ID: wpr-968369

ABSTRACT

Although Apiospora Sacc. has previously been considered a sexual morph of Arthrinium species on the basis of phylogenetic, morphological, and ecological diagnoses, a recent study delimited these as different species. Recently, 14 species, including eight new species, of marine Arthrinium have been reported from Korea. Six known species have previously been renamed as species in the genus Apiospora (A. arundinis, A. marii, A. piptatheri, A. rasikravindrae, A. sacchari, and A. saccharicola). However, the eight new species of marine Arthrinium (Ar. agari, Ar. arctoscopi, Ar. fermenti, Ar. koreanum, Ar. marinum, Ar. pusillispermum, Ar. sargassi, and Ar. taeanense) are yet to be studied, and thus the taxonomic status of these species remains to be clarified. In this study, we conducted phylogenetic analyses using the internal transcribed spacer, 28S large subunit ribosomal RNA gene, translation elongation factor 1-alpha, and beta-tubulin regions to confirm the phylogenetic position of these eight species. Based on these analyses, we re-identified the eight Arthrinium species as new combinations in Apiospora. Additionally, among the six known Apiospora species, two (A. piptatheriand A. rasikravindrae) have not previously been recorded in Korea. On the basis of morphological and molecular analyses, we report these as new species in Korea. Herein, we present scanning electron micrographs detailing the morphologies of these species, along with phylogenetic trees and detailed descriptions.

3.
Mycobiology ; : 203-212, 2022.
Article in English | WPRIM | ID: wpr-968359

ABSTRACT

Fungi act as important decomposers in the forest environment. They recycle essential nutrients, promote plant growth through mycorrhizal relationships, and act as food for small animals. Samples of 265 indigenous fungal species were collected from Mudeungsan National Park in 2020. These species were identified based on morphological, molecular, and phylogenetic analyses using the internal transcribed spacer (ITS), nuclear large subunit rRNA (LSU), and RNA polymerase II second largest subunit (rpb2) regions. Subsequently, seven species were identified as unrecorded species in Korea: Cordyceps cicadae, Dentocorticium bicolor, Hymenochaete nanospora, Physisporinus crataegi, Rigidoporus piceicola, Russula raoultii, and Scutellinia crinita. This study reveals their detailed macro- and microscopic morphological characteristics with phylogenetic trees to report them as unrecorded species in Korea.

4.
Psychiatry Investigation ; : 670-678, 2021.
Article in English | WPRIM | ID: wpr-903190

ABSTRACT

Objective@#Accurate motor timing is critical for efficient motor control of behaviors; however, the effect of motor timing abilities on movement-related neural activities has rarely been investigated. The current study aimed to examine the electrophysiological correlates of motor timing errors. @*Methods@#Twenty-two healthy volunteers performed motor timing tasks while their electroencephalographic and electromyographic (EMG) activities were simultaneously recorded. The average of intervals between consecutive EMG onsets was calculated separately for each subject. Motor timing error was calculated as an absolute discrepancy value between the subjects’ produced and given time interval. A movement-related potential (MRP) analysis was conducted using readings from Cz electrode. @*Results@#Motor timing errors and MRPs were significantly correlated. Our principal finding was that only Bereitschaftpotential (BP) and motor potential (MP), not movement monitoring potential, were significantly attenuated in individuals with motor timing errors. Motor timing error had a significant effect on the amplitude of the late BP and MP. @*Conclusion@#The findings provide electrophysiological evidence that motor timing errors correlate with the neural processes involved in the generation of self-initiated voluntary movement. Alterations in MRPs reflect central motor control processes and may be indicative of motor timing deficits.

5.
Psychiatry Investigation ; : 670-678, 2021.
Article in English | WPRIM | ID: wpr-895486

ABSTRACT

Objective@#Accurate motor timing is critical for efficient motor control of behaviors; however, the effect of motor timing abilities on movement-related neural activities has rarely been investigated. The current study aimed to examine the electrophysiological correlates of motor timing errors. @*Methods@#Twenty-two healthy volunteers performed motor timing tasks while their electroencephalographic and electromyographic (EMG) activities were simultaneously recorded. The average of intervals between consecutive EMG onsets was calculated separately for each subject. Motor timing error was calculated as an absolute discrepancy value between the subjects’ produced and given time interval. A movement-related potential (MRP) analysis was conducted using readings from Cz electrode. @*Results@#Motor timing errors and MRPs were significantly correlated. Our principal finding was that only Bereitschaftpotential (BP) and motor potential (MP), not movement monitoring potential, were significantly attenuated in individuals with motor timing errors. Motor timing error had a significant effect on the amplitude of the late BP and MP. @*Conclusion@#The findings provide electrophysiological evidence that motor timing errors correlate with the neural processes involved in the generation of self-initiated voluntary movement. Alterations in MRPs reflect central motor control processes and may be indicative of motor timing deficits.

6.
Psychiatry Investigation ; : 452-459, 2020.
Article | WPRIM | ID: wpr-832568

ABSTRACT

Objective@#Little has been explored about a reflection towards self-image in schizophrenia, though it can be related to heterogeneous symptoms of the illness. We identified the neural basis of ambivalence towards ideal self-image in patients with schizophrenia. @*Methods@#20 patients with schizophrenia and 20 healthy controls underwent functional MRI while the self-image reflection tasks of determining whether to agree with sentences describing their actual or ideal self-image that contained one of the adjective pairs with opposite valence. The interaction between the group and ideal ambivalence score was examined, and group differences in functional connectivity related to ambivalence towards ideal self-image were further studied. @*Results@#The interaction of group-by-ideal ambivalence score was shown in the dorsal anterior cingulate cortex and dorsolateral prefrontal cortex, where activities were positively correlated with the level of ideal self-image ambivalence in patients, but not in controls. Task-related decrease in functional connectivity was shown between the orbitofrontal cortex and cerebellum in patients. @*Conclusion@#The process of reflecting on ambivalent ideal self-image in schizophrenia may be related to aberrant prefrontal activity and connectivity. Abnormality in the prefrontal regions that take part in cognitive conflict monitoring and value judgment may underlie the pathophysiology of increased ambivalence towards ideal self-image.

7.
Psychiatry Investigation ; : 1207-1215, 2020.
Article in English | WPRIM | ID: wpr-903155

ABSTRACT

Objective@#Enhancing subjective well-being is an effective way to improve mental health. This study aimed to validate a virtual reality-based interactive feedback program as an intervention tool for promoting subjective well-being. @*Methods@#Thirty-six males participated in this program, consisting of three tasks constructed based on the theories of positive psychology: ‘Experience-based problem recognition task’, ‘Future self-based success story expression task’, and ‘Strength expression task’. Participants rated visual analog scores associated with each of the tasks’ contents. The concurrent validity of task scores was evaluated by correlations with the psychological scale scores. @*Results@#The total task score was positively correlated with scores of Mental Health Continuum-Short Form (MHC-SF) emotional well-being and psychological well-being, Rosenberg’s Self-Esteem Scale, Dispositional Hope Scale agency dimension and pathways dimension, and Life Orientation Test Revised, but not with MHC-SF social well-being scores. After controlling for the effects of the other task scores, the task scores had linear relationships with certain psychological assessments. @*Conclusion@#Since the task scores are closely related to indicators of well-being, self-esteem, hope, and optimism, the program contents are well associated with certain aspects of subjective well-being and thus may be available for training that improves subjective well-being through interactive feedback.

8.
Natural Product Sciences ; : 340-344, 2020.
Article in English | WPRIM | ID: wpr-902764

ABSTRACT

A new chromone analogue (1) was isolated from an EtOAc-extract of Pleosporales sp. culture medium, together with five known chromones (2 – 6). The isolation workflow was guided by a Molecular Networking-based dereplication strategy. The chemical structure of the new compound was elucidated using NMR and MS spectroscopy, and the absolute configuration was established by the Mosher's method. All isolated compounds were evaluated for their inhibitory effects on lipopolysaccharide-induced nitirc oxide production in RAW 264.7 macrophages. Compound 1 showed marginal inhibitory activity with an IC50 value of 118.7 μM.

9.
Psychiatry Investigation ; : 1207-1215, 2020.
Article in English | WPRIM | ID: wpr-895451

ABSTRACT

Objective@#Enhancing subjective well-being is an effective way to improve mental health. This study aimed to validate a virtual reality-based interactive feedback program as an intervention tool for promoting subjective well-being. @*Methods@#Thirty-six males participated in this program, consisting of three tasks constructed based on the theories of positive psychology: ‘Experience-based problem recognition task’, ‘Future self-based success story expression task’, and ‘Strength expression task’. Participants rated visual analog scores associated with each of the tasks’ contents. The concurrent validity of task scores was evaluated by correlations with the psychological scale scores. @*Results@#The total task score was positively correlated with scores of Mental Health Continuum-Short Form (MHC-SF) emotional well-being and psychological well-being, Rosenberg’s Self-Esteem Scale, Dispositional Hope Scale agency dimension and pathways dimension, and Life Orientation Test Revised, but not with MHC-SF social well-being scores. After controlling for the effects of the other task scores, the task scores had linear relationships with certain psychological assessments. @*Conclusion@#Since the task scores are closely related to indicators of well-being, self-esteem, hope, and optimism, the program contents are well associated with certain aspects of subjective well-being and thus may be available for training that improves subjective well-being through interactive feedback.

10.
Natural Product Sciences ; : 340-344, 2020.
Article in English | WPRIM | ID: wpr-895060

ABSTRACT

A new chromone analogue (1) was isolated from an EtOAc-extract of Pleosporales sp. culture medium, together with five known chromones (2 – 6). The isolation workflow was guided by a Molecular Networking-based dereplication strategy. The chemical structure of the new compound was elucidated using NMR and MS spectroscopy, and the absolute configuration was established by the Mosher's method. All isolated compounds were evaluated for their inhibitory effects on lipopolysaccharide-induced nitirc oxide production in RAW 264.7 macrophages. Compound 1 showed marginal inhibitory activity with an IC50 value of 118.7 μM.

11.
Mycobiology ; : 50-58, 2019.
Article in English | WPRIM | ID: wpr-760527

ABSTRACT

Agarum clathratum, a brown macroalgae species, has recently become a serious environmental problem on the coasts of Korea. In an effort to solve this problem, fungal diversity associated with decaying A. clathratum was investigated and related β-glucosidase and endoglucanase activities were described. A total of 233 fungal strains were isolated from A. clathratum at 15 sites and identified 89 species based on morphology and a multigene analysis using the internal transcribed spacer region (ITS) and protein-coding genes including actin (act), β-tubulin (benA), calmodulin (CaM), and translation elongation factor (tef1). Acremonium, Corollospora, and Penicillium were the dominant genera, and Acremonium fuci and Corollospora gracilis were the dominant species. Fifty-one species exhibited cellulase activity, with A. fuci, Alfaria terrestris, Hypoxylon perforatum, P. madriti, and Pleosporales sp. Five showing the highest enzyme activities. Further enzyme quantification confirmed that these species had higher cellulase activity than P. crysogenum, a fungal species described in previous studies. This study lays the groundwork for bioremediation using fungi to remove decaying seaweed from populated areas and provides important background for potential industrial applications of environmentally friendly processes.


Subject(s)
Acremonium , Actins , Biodegradation, Environmental , Calmodulin , Cellulase , Fungi , Korea , Penicillium , Peptide Elongation Factors , Seaweed
12.
Korean Journal of Psychosomatic Medicine ; : 35-41, 2019.
Article in Korean | WPRIM | ID: wpr-760244

ABSTRACT

OBJECTIVES: Although delirium is a common complication among patients hospitalized in intensive care units(ICUs), little is known about the roles that diagnostic and therapeutic procedures play in its development. This study investigates the procedure-related risk factors of delirium in ICU patients. METHODS: All the consecutive patients admitted to the ICU between June 2016 and May 2017 were routinely evaluated for delirium by psychiatrists. In total, 1156 patients met the inclusion criteria and were retrospectively analyzed. A multiple logistic regression analysis was conducted to investigate independent risk factors of delirium development while adjusting for other characteristics. RESULTS: The age, Acute Physiology and Chronic Health Evaluation (APACHE II) score, proportion of patients who had undergone an operation, and proportion of patients who were foley catheterized, mechanically ventilated, and physically restrained were higher in the delirium group. The multiple logistic regression analysis confirmed that the use of restraint was an independent risk factor of delirium (odds ratio : 10.006 ; 95% confidence interval : 6.120–16.360 ; p<0.001). The patient factors independently associated with delirium were an advanced age and a higher APACHE II score. The incidence of delirium was 15.3%. CONCLUSIONS: There is a high prevalence of delirium influenced by potentially harmful procedures in patients in ICU settings. The use of physical restraint had the strongest association with the development of delirium. These findings advocate the need to target procedure-related risk factors such as the use of restraints as preventive intervention measures for ICU delirium.


Subject(s)
Humans , APACHE , Catheters , Critical Care , Delirium , Incidence , Intensive Care Units , Logistic Models , Prevalence , Psychiatry , Restraint, Physical , Retrospective Studies , Risk Factors
13.
Korean Journal of Psychosomatic Medicine ; : 101-110, 2019.
Article in Korean | WPRIM | ID: wpr-918147

ABSTRACT

OBJECTIVES@#It is not clear which clinical variables are most closely associated with delirium in the Intensive Care Unit (ICU). By comparing clinical data of ICU delirium and non-delirium patients, we sought to identify variables that most effectively differentiate delirium from non-delirium.@*METHODS@#Medical records of 6,386 ICU patients were reviewed. Random Subset Feature Selection and Principal Component Analysis were utilized to select a set of clinical variables with the highest discriminatory capacity. Statistical analyses were employed to determine the separation capacity of two models-one using just the selected few clinical variables and the other using all clinical variables associated with delirium.@*RESULTS@#There was a significant difference between delirium and non-delirium individuals across 32 clinical variables. Richmond Agitation Sedation Scale (RASS), urinary catheterization, vascular catheterization, Hamilton Anxiety Rating Scale (HAM-A), Blood urea nitrogen, and Acute Physiology and Chronic Health Examination II most effectively differentiated delirium from non-delirium. Multivariable logistic regression analysis showed that, with the exception of vascular catheterization, these clinical variables were independent risk factors associated with delirium. Separation capacity of the logistic regression model using just 6 clinical variables was measured with Receiver Operating Characteristic curve, with Area Under the Curve (AUC) of 0.818. Same analyses were performed using all 32 clinical variables;the AUC was 0.881, denoting a very high separation capacity.@*CONCLUSIONS@#The six aforementioned variables most effectively separate delirium from non-delirium. This highlights the importance of close monitoring of patients who received invasive medical procedures and were rated with very low RASS and HAM-A scores.

14.
Psychiatry Investigation ; : 306-313, 2019.
Article in English | WPRIM | ID: wpr-760923

ABSTRACT

OBJECTIVE: Self-esteem and self-consciousness are important determinants of behaviors. This study aimed to explore the relationship between self-esteem and self-consciousness in adolescents using the eye-tracking measurement. METHODS: Fifty-five adolescents with high self-esteem and 58 adolescents with low self-esteem participated in self-consciousness-related eye-tracking experiments of selecting happy, disgusted, and angry facial emotions while recognizing one's own usual expressions and the others' usual expressions toward oneself. RESULTS: When recognizing one's own, adolescents with high self-esteem showed significantly more selection counts and longer fixation time for ‘happy’ than adolescents with low self-esteem. When recognizing the others', adolescents with low self-esteem showed significantly more selection counts and longer fixation time for ‘disgusted’ and ‘angry’ than adolescents with high self-esteem. CONCLUSION: These suggest higher self-esteem is connected to more positive identification of one's usual expressions and others' usual expressions toward oneself. There is a close relationship among low self-esteem, suppressing positive emotions, decreased psychological adjustment, and increased negative emotions.


Subject(s)
Adolescent , Humans , Emotional Adjustment
15.
Korean Journal of Schizophrenia Research ; : 37-42, 2018.
Article in Korean | WPRIM | ID: wpr-738911

ABSTRACT

OBJECTIVES: Magical ideation refers to belief in forms of causation that by conventional standards are invalid, and is considered to be one of prodromal psychotic symptoms in schizophrenia. This study aimed to investigate the relationship between magical ideation and eye gaze pattern in patients with schizophrenia. METHODS: Eye gaze data were recorded in 23 patients with schizophrenia and 23 healthy controls while performing the reality evaluation task, in which participants should judge the realness of real or unreal pictures. RESULTS: Compared to healthy controls, patients with schizophrenia showed decreased fixation, saccade and area of interest (AOI) fixation counts, and reduced scanpath length. Magical Ideation Scale score in patients with schizophrenia showed negative correlation with the scanpath length in the real condition and the AOI fixation count in the unreal condition. CONCLUSION: These findings suggest that patients with schizophrenia show restricted visual scanning during reality evaluation, and their restricted visual scanning may play an important role in the magical ideation.


Subject(s)
Humans , Magic , Saccades , Schizophrenia
16.
Korean Journal of Psychosomatic Medicine ; : 194-200, 2018.
Article in Korean | WPRIM | ID: wpr-738892

ABSTRACT

OBJECTIVES: The significance of leukoaraiosis on brain magnetic resonance imaging (MRI) is uncertain, but it is often seen with vascular risk factors or in the context of cognitive impairment. We aimed to investigate the effect of leukoaraiosis on the severity and course of delirium. METHODS: Periventricular hyperintensity and deep white matter hyperintensity on brain MRI were rated in 42 patients with delirium by semiquantative visual rating scale. Correlations between their grades and the scores of Korean version of Delirium Rating Scale-Revised-98 (K-DRS-R-98) were analyzed, and the interaction effects between the groups according to the levels of leukoaraiosis and two evaluation points were also analyzed. RESULTS: The grade of deep white matter hyperintensity in the occipital lobe was positively correlated with the scores on the total, severity items, cognitive items, and non-cognitive items of K-DRS-R-98. The cognitive items scores of K-DRS-R-98 in the low grade group of periventricular hyperintensity showed significantly steeper decrease than the high grade group. CONCLUSIONS: A difference in severity or recovery speed of delirium according to the level of leukoaraiosis may result from disruption in brain functional connectivity. Our results have a clinical implication in that the severity and course of delirium can be possibly predicted using the level of leukoaraiosis.


Subject(s)
Humans , Brain , Cognition Disorders , Delirium , Leukoaraiosis , Magnetic Resonance Imaging , Occipital Lobe , Risk Factors , White Matter
17.
Mycobiology ; : 177-184, 2018.
Article in English | WPRIM | ID: wpr-729781

ABSTRACT

The genus Trichoderma (Hypocreaceae, Ascomycota) consists of globally distributed fungi. Among them, T. harzianum, one of the most commonly collected Trichoderma species, had been known as a polyphyletic or aggregate species. However, a total of 19 species were determined from the polyphyletic groups of T. harzianum. Thus, we explored Korean “T. harzianum” specimens that were collected in 2013–2014. These specimens were re-examined based on a recent study with translate elongation factor 1-alpha (EF1α) sequences to reveal cryptic Trichoderma species in Korea. As a result, four different species, T. afroharzianum, T. atrobruneum, T. pyramidale, and T. harzianum, were identified. Except T. harzianum, the other three species have not been reported in Korea. In this work, we describe these species and provide figures.


Subject(s)
Classification , Fungi , Korea , Peptide Elongation Factors , Phylogeny , Trichoderma
18.
Mycobiology ; : 269-277, 2018.
Article in English | WPRIM | ID: wpr-729771

ABSTRACT

The production of water-soluble pigments by fungal strains indigenous to South Korea was investigated to find those that are highly productive in submerged culture. Among 113 candidates, 34 strains that colored the inoculated potato dextrose agar medium were selected. They were cultured in potato dextrose broth and extracted with ethanol. The productivity, functionality (radical-scavenging activities), and color information (CIELAB values) of the pigment extracts were measured. Five species produced intense yellowish pigments, and two produced intense reddish pigments that ranked the highest in terms of absorbance units produced per day. The pigment extracts of Penicillium miczynskii, Sanghuangporus baumii, Trichoderma sp. 1, and Trichoderma afroharzianum exhibited high radical-scavenging activity. However, the S. baumii extract showed moderate toxicity in the acute toxicity test, which limits the industrial application of this pigment. In conclusion, P. miczynskii KUC1721, Trichoderma sp. 1 KUC1716, and T. afroharzianum KUC21213 were the best fungal candidates to be industrial producers of safe, functional water-soluble pigments.


Subject(s)
Agar , Colorimetry , Efficiency , Ethanol , Fungi , Glucose , Korea , Penicillium , Solanum tuberosum , Toxicity Tests, Acute , Trichoderma
19.
Journal of the Korean Society of Biological Psychiatry ; : 26-31, 2017.
Article in Korean | WPRIM | ID: wpr-725376

ABSTRACT

OBJECTIVES: normal circadian rhythm of autonomic nervous system function stands for the daily change of sympathetic and parasympathetic modulation, which can be measured by heart rate variability (HRV). Generally, patients in the intensive care unit (ICU) are prone to sleep-wake cycle dysregulation, therefore, it may have an influence on the circadian rhythm of autonomic nervous system. This study was designed to interpret possible dysregulation of autonomic nervous system in ICU patients by using HRV. METHODS: HRV was assessed every 3 hours in 21 ICU patients during a 7-minute period. The statistical differences of HRV features between the morning (AM 6 : 00–PM 12 : 00), and the afternoon (PM 12 : 00–PM 18 : 00) periods were evaluated in time domain and frequency domain. RESULTS: Patients showed significantly increased normalized power of low frequencey (nLF), absolute power of low frequencey (LF)/absolute power of high frequencey (HF) in the afternoon period as compared to the morning period. However, normalized power of high frequency (nHF) was significantly decreased in the afternoon period. There was no statistically significant difference between the morning period and the afternoon period in the time domain analysis. CONCLUSIONS: The increased sympathetic tone in the afternoon period supports possible dysregulation in the circadian rhythm of autonomic nervous system in ICU patients. Future studies can help to interpret the association between autonomic dysregulation and negative outcomes of ICU patients.


Subject(s)
Humans , Autonomic Nervous System , Circadian Rhythm , Critical Care , Heart Rate , Heart , Intensive Care Units
20.
Journal of the Korean Society of Biological Psychiatry ; : 52-58, 2017.
Article in Korean | WPRIM | ID: wpr-725372

ABSTRACT

Due to the increasing use of the internet, various social problems have been emerging, and one of them is internet gaming disorder (IGD). The purpose of this study was to investigate whether low internal motivation was present in IGD and basic psychological needs affected internal motivation. Twenty-one individuals with IGD and 21 healthy controls performed a ‘motivation task’ in which the avatar in virtual reality asked whether they would accept an activity in two conditions stimulating intrinsic or extrinsic motivation. The task performance was compared between the two groups, and was correlated with the Basic Psychological Needs Scale scores. Patients had a significantly lower acceptance rate of the proposal in the intrinsic motivation condition than controls, and this intrinsic motivated tendency was correlated with the satisfaction in their basic psychological needs. As with other substance use disorders, IGD was associated with a lower level of internal motivation, which was related to the dissatisfaction of basic psychological needs such as autonomy, competence, and relationship.


Subject(s)
Humans , Immunoglobulin D , Internet , Mental Competency , Motivation , Social Problems , Substance-Related Disorders , Task Performance and Analysis
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