1.Assessment of Esophageal Reconstruction via Bioreactor Cultivation of a Synthetic Scaffold in a Canine Model
In Gul KIM ; Yanru WU ; Su A PARK ; Ji Suk CHOI ; Seong Keun KWON ; Seung Hong CHOI ; Kyeong Cheon JUNG ; Jung-Woog SHIN ; Eun-Jae CHUNG
Clinical and Experimental Otorhinolaryngology 2023;16(2):165-176
Objectives:
. Using tissue-engineered materials for esophageal reconstruction is a technically challenging task in animals that requires bioreactor training to enhance cellular reactivity. There have been many attempts at esophageal tissue engineering, but the success rate has been limited due to difficulty in initial epithelialization in the special environment of peristalsis. The purpose of this study was to evaluate the potential of an artificial esophagus that can enhance the regeneration of esophageal mucosa and muscle through the optimal combination of a double-layered polymeric scaffold and a custom-designed mesenchymal stem cell-based bioreactor system in a canine model.
Methods:
. We fabricated a novel double-layered scaffold as a tissue-engineered esophagus using an electrospinning technique. Prior to transplantation, human-derived mesenchymal stem cells were seeded into the lumen of the scaffold, and bioreactor cultivation was performed to enhance cellular reactivity. After 3 days of cultivation using the bioreactor system, tissue-engineered artificial esophagus was transplanted into a partial esophageal defect (5×3 cm-long resection) in a canine model.
Results:
. Scanning electron microscopy (SEM) showed that the electrospun fibers in a tubular scaffold were randomly and circumferentially located toward the inner and outer surfaces. Complete recovery of the esophageal mucosa was confirmed by endoscopic analysis and SEM. Esophagogastroduodenoscopy and computed tomography also showed that there were no signs of leakage or stricture and that there was a normal lumen with complete epithelialization. Significant regeneration of the mucosal layer was observed by keratin-5 immunostaining. Alpha-smooth muscle actin immunostaining showed significantly greater esophageal muscle regeneration at 12 months than at 6 months.
Conclusion
. Custom-designed bioreactor cultured electrospun polyurethane scaffolds can be a promising approach for esophageal tissue engineering.
2.Effects of rosiglitazone, an antidiabetic drug, on Kv3.1 channels
Hyang Mi LEE ; Seong Han YOON ; Min-Gul KIM ; Sang June HAHN ; Bok Hee CHOI
The Korean Journal of Physiology and Pharmacology 2023;27(1):95-103
Rosiglitazone is a thiazolidinedione-class antidiabetic drug that reduces blood glucose and glycated hemoglobin levels. We here investigated the interaction of rosiglitazone with Kv3.1 expressed in Chinese hamster ovary cells using the wholecell patch-clamp technique. Rosiglitazone rapidly and reversibly inhibited Kv3.1 currents in a concentration-dependent manner (IC 50 = 29.8 µM) and accelerated the decay of Kv3.1 currents without modifying the activation kinetics. The rosiglitazonemediated inhibition of Kv3.1 channels increased steeply in a sigmoidal pattern over the voltage range of –20 to +30 mV, whereas it was voltage-independent in the voltage range above +30 mV, where the channels were fully activated. The deactivation of Kv3.1 current, measured along with tail currents, was also slowed by the drug. In addition, the steady-state inactivation curve of Kv3.1 by rosiglitazone shifts to a negative potential without significant change in the slope value. All the results with the use dependence of the rosiglitazone-mediated blockade suggest that rosiglitazone acts on Kv3.1 channels as an open channel blocker.
3.Relationship between the Spectral Power Density of Sleep Electroencephalography and Psychiatric Symptoms in Patients with Breathing-related Sleep Disorder
Jae Myeong KANG ; Seo-Eun CHO ; Gun Bae LEE ; Seong-Jin CHO ; Kee Hyung PARK ; Seon Tae KIM ; Seung-Gul KANG
Clinical Psychopharmacology and Neuroscience 2021;19(3):521-529
Objective:
Patients with breathing-related sleep disorder (BRSD) often complain of psychiatric symptoms such as depression in addition to snoring, excessive sleepiness, and disturbed sleep. However, the relationship between psychiatric symptoms and severity of sleep apnea in BRSD is controversial. We conducted this study to investigate the relationship between psychiatric symptoms and sleep electroencephalography (EEG) findings in BRSD patients using spectral analysis.
Methods:
All participants underwent polysomnography and evaluation using Symptom Checklist-90-Revised (SCL-90-R) scale. We analyzed the absolute spectral power density values of standard EEG frequency bands in the participants (n = 169) with BRSD during the non-rapid eye movement (NREM) sleep period. We performed correlation analysis between the domain scores of SCL-90-R scale and the absolute values of the EEG frequency bands.
Results:
Significant positive correlation was observed between the absolute spectral power density values in the slow oscillation band and the degree of paranoid ideation (r = 0.226, p = 0.028) and depression (r = 0.216, p = 0.044) in SCL-90-R. The multiple linear regression model showed that higher paranoid ideation domain score (B = 0.007, p = 0.020), younger age (B = −0.011, p < 0.001), and female sex (B = 0.213, p = 0.004) were associated with higher slow oscillation power during NREM sleep.
Conclusion
The results of the present study suggested a relationship between sleep EEG and psychiatric symptoms in patients with BRSD. This relationship needs to be validated with further studies.
4.Usefulness of Synthetic Osteoconductive Bone Graft Substitute with Zeta Potential Control for Intramedullary Fixation with Proximal Femur Nail Antirotation in Osteoporotic Unstable Femoral Intertrochanteric Fracture
Tae-Woo SUNG ; Ein-Seong LEE ; Ok-Gul KIM ; Ki-Seong HEO ; Won Yong SHON
Hip & Pelvis 2021;33(4):211-218
Purpose:
This study was conducted in order to examine the usefulness of osteoconductive bone substitutes with zeta potential control (geneX® ds; Biocomposites, England) by comparing the complications and radiographic evaluation with or without geneX® ds augmentation for internal fixation with proximal femur nail antirotation (PFNA) for treatment of osteoporotic unstable intertrochanteric fractures.
Materials and Methods:
A retrospective study of 101 patients who underwent fixation with PFNA in osteoporotic unstable intertrochanteric fractures was conducted from December 2015 to August 2020. The radiographic evaluation and complication rates were compared between patients with geneX® ds (Group A: 41 cases) and those without geneX® ds (Group B: 60 cases).
Results:
In radiological valuation, the degree of blade sliding from the time immediately after surgery to one year after surgery was 1.4±1.2 mm and 5.8±2.7 mm in Group A and Group B, respectively (P<0.001). During the same time frame, a significant difference of 2.3±2.2° and 7.4±3.1° , respectively (P<0.001), in varus collapse, was observed for Group A and Group B.
Conclusion
Among patients fixed with PFNA for treatment of unstable intertrochanteric fractures, less blade sliding and varus collapse was observed for those with geneX® ds augmentation compared to those without it. In addition, there was no increase in the incidence of complications. The authors believe it can be regarded as a safe and effective additive for intramedullary fixation for treatment of unstable intertrochanteric fractures.
5.Relationship between the Spectral Power Density of Sleep Electroencephalography and Psychiatric Symptoms in Patients with Breathing-related Sleep Disorder
Jae Myeong KANG ; Seo-Eun CHO ; Gun Bae LEE ; Seong-Jin CHO ; Kee Hyung PARK ; Seon Tae KIM ; Seung-Gul KANG
Clinical Psychopharmacology and Neuroscience 2021;19(3):521-529
Objective:
Patients with breathing-related sleep disorder (BRSD) often complain of psychiatric symptoms such as depression in addition to snoring, excessive sleepiness, and disturbed sleep. However, the relationship between psychiatric symptoms and severity of sleep apnea in BRSD is controversial. We conducted this study to investigate the relationship between psychiatric symptoms and sleep electroencephalography (EEG) findings in BRSD patients using spectral analysis.
Methods:
All participants underwent polysomnography and evaluation using Symptom Checklist-90-Revised (SCL-90-R) scale. We analyzed the absolute spectral power density values of standard EEG frequency bands in the participants (n = 169) with BRSD during the non-rapid eye movement (NREM) sleep period. We performed correlation analysis between the domain scores of SCL-90-R scale and the absolute values of the EEG frequency bands.
Results:
Significant positive correlation was observed between the absolute spectral power density values in the slow oscillation band and the degree of paranoid ideation (r = 0.226, p = 0.028) and depression (r = 0.216, p = 0.044) in SCL-90-R. The multiple linear regression model showed that higher paranoid ideation domain score (B = 0.007, p = 0.020), younger age (B = −0.011, p < 0.001), and female sex (B = 0.213, p = 0.004) were associated with higher slow oscillation power during NREM sleep.
Conclusion
The results of the present study suggested a relationship between sleep EEG and psychiatric symptoms in patients with BRSD. This relationship needs to be validated with further studies.
6.The Characteristics of First Suicide Attempt Patients with Self-poisoning: Comparison of Patients with Self-injury.
Kyu Sung CHOI ; Jae Hyug WOO ; Yong Su LIM ; Jin Joo KIM ; Jae Ho JANG ; Woo Sung CHOI ; Kyung Jin MIN ; Seong Jin CHO ; Seung Gul KANG ; Kyoung Sae NA
Journal of the Korean Society of Emergency Medicine 2017;28(5):493-501
PURPOSE: This study was conducted to compare the characteristics of first suicide attempt patients with self-poisoning with those of self-injured patients. METHODS: In this retrospective data analysis, data were collected from emergency department patients who made a first suicide attempt between October 2013 and January 2017. Data included demographic, socioeconomic, physical and mental health status, method of suicide attempt, and authenticity of suicide intent. Patients were classified into a self-poisoning and self-injury group. RESULTS: Among 2,252 patients, 788 patients were making their first suicide attempt. Of these patients, 443 were self-poisoning patients. Males were less common among the self-poisoning group. Cohabitants (303 [89.4%] vs. 193 [81.4%]; p=0.010), married state (214 [57.4%] vs. 108 [41.2%]; p<0.001), and asking for help after suicide attempt (136 [86.1%] vs. 103 [73.6%]; p=0.009) was more common in the self-poisoning group than the self-injury group. However, planned suicide attempt was more frequent in the self-injury group (26 [16.0%] vs. 9 [4.7%]; p=0.001). Moreover, authenticity of suicide intent was higher in the self-injury group (12 [11.3%] vs. 42 [40.4%]; p<0.001). CONCLUSION: In the self-poisoning group, there was a higher rate of females, married people, existing cohabitants, and tendency to ask for help after suicide attempt. There were also more impulsive suicide attempts in this group. The results presented herein will help prevent self-poisoning suicide attempts among high risk patients.
Emergency Service, Hospital
;
Female
;
Humans
;
Male
;
Mental Health
;
Methods
;
Poisoning
;
Retrospective Studies
;
Statistics as Topic
;
Suicide*
7.Directing Human Embryonic Stem Cells towards Functional Endothelial Cells Easily and without Purification.
Chang Hyun GIL ; Byeong Seong KI ; Joseph SEO ; Jong Jin CHOI ; Hana KIM ; In Gul KIM ; A Ra JUNG ; Won Young LEE ; Youngsok CHOI ; Kwideok PARK ; Sung Hwan MOON ; Hyung Min CHUNG
Tissue Engineering and Regenerative Medicine 2016;13(3):274-283
Hemangioblasts or blood islands only arise in early development thereby the sources to obtain these bi-potential cells are limited. While previous studies have isolated both lineages in vitro through the hemangioblast, derivation efficiency was rather low due to cellular damage attributed by enzyme usage and fluorescent activated cell sorting (FACS). This study focused on avoiding the use of damaging factors in the derivation of endothelial cells (ECs). Single cell H9-human embryonic stem cells (hESCs) were obtained by using a mild dissociation protocol then human embryoid body (hEB) formation was performed under hemangioblast differentiation conditions. The hEBs were subjected to a two-stage cytokine treatment procedure. Subsequent culture of the adhesive cells in day 4 hEBs gave arise to a seemingly pure population of ECs. The hESC-derived ECs were characterized by identifying signature endothelial gene and protein markers as well as testing for in vitro functionality. Furthermore, in vivo functionality was also confirmed by transplanting the cells in hindlimb ischemic murine models. We demonstrate that the genetic change required for EC derivation precedes blast colony formation. Furthermore, cell damage was prevented by abating enzyme usage and FACS, resulting in a high yield of ECs upon adhesion. Under this method, confluent cultures of ECs were obtainable 4 days after hEB formation which is significantly faster than previous protocols.
Adhesives
;
Animals
;
Embryoid Bodies
;
Embryonic Stem Cells
;
Endothelial Cells*
;
Hemangioblasts
;
Hindlimb
;
Human Embryonic Stem Cells*
;
Humans*
;
In Vitro Techniques
;
Islands
;
Methods
8.Attempted Suicides in South Korea : A Multi-Center Analysis of Causes, Methods, and Psychiatric Diagnoses of Suicidal Attempters in 2013.
Hyeyoung KIM ; Bora KIM ; Seung Gul KANG ; Moon Doo KIM ; Min Hyuk KIM ; Soo In KIM ; Jae Min KIM ; Eunsoo MOON ; Joon Ho AHN ; Kyung Uk LEE ; Sang Hyuk LEE ; Seung Jae LEE ; Seong Hoon JEONG ; Young Chul CHUNG ; Hee Yeon JUNG ; Gawon JU ; Boseok CHA ; Tae Hyon HA ; Yong Min AHN
Journal of the Korean Society of Biological Psychiatry 2015;22(4):187-194
OBJECTIVES: To examine direct causes of attempted suicides, methods adopted to commit suicide, and psychiatric diagnoses among suicide attempters in South Korea. METHODS: A total of 1359 suicide attempters who had visited emergency department of 17 medical centers due to suicide attempt from May 2013 to Nov 2013 were interviewed using semi-structured questionnaires. RESULTS: Psychiatric symptoms were the most common cause of suicide attempts (62.2%), followed by interpersonal relationships (24.4%). Women attempted suicide more often for interpersonal reasons, whereas men were more likely to do so for financial and jobrelated reasons. Half of participants (55.8%) attempted suicide by drug intoxication, which was more prevalent among females and those who had previous history of psychiatric disease or previous suicide attempt. Men were more likely to use more lethal methods such as pesticide poisoning and gas inhalation than women. Pesticide poisoning was also prevalent among the elderly group and the rural population. Near ninety-five percent (94.5%) of participants received a psychiatric diagnosis : the most frequent diagnosis was depressive disorder. CONCLUSIONS: This is the first nationwide study of cases of attempted suicide. When stratified by age groups, gender, urbanicity, living alone or not, presence of physical illness, previous psychiatric history, and previous suicide attempt, there were significant differences with respect to causes, methods of attempted suicides and psychiatric diagnoses of suicide attempters.
Aged
;
Depressive Disorder
;
Diagnosis*
;
Emergency Service, Hospital
;
Female
;
Humans
;
Inhalation
;
Korea*
;
Male
;
Mental Disorders
;
Methods*
;
Poisoning
;
Rural Population
;
Suicide*
;
Suicide, Attempted
9.Attitude toward Suicide and Personal Experiences of Suicide among Doctors and Health Care Workers in Korea.
Joong Il KWON ; Yu Jin LEE ; Su Jin KWON ; Jong Woo PAIK ; Jun Hee JEON ; Seung Gul KANG ; Seung Min BAE ; Jong Hoon KIM ; In Hee CHO ; Seong Jin CHO
Journal of Korean Neuropsychiatric Association 2013;52(4):231-242
OBJECTIVES: The aim of this study was to investigate attitudes toward suicide and personal experiences with suicide among doctors and health care workers in Korea. METHODS: A total of 622 participants were included in this study and 617 participants completed a self-report questionnaire that included 31 items; 184 doctors and 433 health care workers. A questionnaire was used for assessment of demographic characteristics, attitude toward suicide, and personal experiences with suicide in doctors and health care workers. The collected data were evaluated using chi-square and binary logistic regression analyses. A probability level of p<0.05 was considered statistically significant. RESULTS: More permissive attitudes toward suicide showed an association with doctor group and non-religious group (p<0.05). Religious group and older age showed an association with a more negative attitude (p<0.05). The lifetime and one-year prevalence rates of suicidal ideation were 31.4% and 9.8%, respectively, in all participants. The lifetime prevalence of suicidal ideation was higher in the religious group (33.9%, p<0.05). Among all participants, 32.1% reported loss of a patient by suicide, and 29.9% reported contact with a patient at risk of suicide or with depression. In addition, 72.5% reported contact with a depressed patient. CONCLUSION: Attitudes toward suicide among doctors and health care workers were shown to differ significantly between age, gender, doctor group and health care worker group, religious group and non-religious group. The reported level of suicidal ideation among doctors and health care workers is worthy of concern. Research is needed for establishment of effective prevention strategies on the basis of our findings.
Delivery of Health Care
;
Depression
;
Humans
;
Korea
;
Logistic Models
;
Prevalence
;
Primary Health Care
;
Surveys and Questionnaires
;
Suicidal Ideation
;
Suicide
10.Anti-obesity and anti-diabetic effects of Yerba Mate (Ilex paraguariensis) in C57BL/6J mice fed a high-fat diet.
Young Rye KANG ; Hak Yong LEE ; Jung Hoon KIM ; Dea In MOON ; Min Young SEO ; Sang Hoon PARK ; Kwang Ho CHOI ; Chang Ryong KIM ; Sang Hyun KIM ; Ji Hyun OH ; Seong Wan CHO ; Sun Young KIM ; Min Gul KIM ; Soo Wan CHAE ; Okjin KIM ; Hong Geun OH
Laboratory Animal Research 2012;28(1):23-29
Yerba Mate, derived from the leaves of the tree, Ilex paraguariensis, is widely-used as a tea or as an ingredient in formulated foods. The aim of the present study was to evaluate the effects of Yerba Mate extract on weight loss, obesity-related biochemical parameters, and diabetes in high-fat diet-fed mice. To this end, by using in vivo animal models of dietary-induced obesity, we have made the interesting observations that Yerba Mate has the ability to decrease the differentiation of pre-adipocytes and to reduce the accumulation of lipids in adipocytes, both of which contribute to a lower growth rate of adipose tissue, lower body weight gain, and obesity. Our data from in vivo studies revealed that Yerba Mate treatment affects food intake, resulting in higher energy expenditure, likely as a result of higher basal metabolism in Yerba Mate-treated mice. Furthermore, in vivo effects of Yerba Mate on lipid metabolism included reductions in serum cholesterol, serum triglycerides, and glucose concentrations in mice that were fed a high fat diet. In conclusion, Yerba Mate can potentially be used to treat obesity and diabetes.
Adipocytes
;
Adipose Tissue
;
Animals
;
Basal Metabolism
;
Body Weight
;
Cholesterol
;
Diet, High-Fat
;
Eating
;
Energy Metabolism
;
Food, Formulated
;
Glucose
;
Ilex paraguariensis
;
Lipid Metabolism
;
Mice
;
Models, Animal
;
Obesity
;
Tea
;
Trees
;
Triglycerides
;
Weight Loss

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