1.Effect and Mechanism of Phosphodiesterase Inhibitors on Trabecular Outflow
Jae Woo KIM ; Jong Been LEE ; So Hyung LEE
Korean Journal of Ophthalmology 2019;33(5):414-421
PURPOSE: Phosphodiesterase (PDE) inhibitors increase matrix metalloproteinase (MMP) production by inhibiting re-uptake of adenosine and may potentiate nitric oxide (NO) activity. This study was performed to investigate the effects and mechanisms of PDE inhibitors on trabecular outflow in cultured human trabecular meshwork cells (HTMCs). METHODS: Primary HTMC cultures were exposed to 0, 20, and 50 µM dipyridamole (DPD) or theophylline (TPN). Permeability through the HTMC monolayer was assessed using carboxyfluorescein. The production of NO was assessed using the Griess assay and MMP-2 levels were measured via Western blotting. RESULTS: DPD significantly increased permeability accompanied with increased nitrite concentration and MMP-2 levels (all p < 0.05). TPN increased nitrite but did not affect permeability or MMP-2 levels significantly (p > 0.05). When treated with DPD and TPN together, both permeability and nitrite production were increased; however, MMP-2 levels showed no difference compared to DPD exposure alone (p > 0.05). CONCLUSIONS: DPD increased trabecular permeability accompanied with increased nitrite production and MMP-2 levels. PDE inhibitors may increase trabecular outflow by increasing MMP-2 levels and by potentiating NO activity through cyclic GMP in HTMC.
Adenosine
;
Blotting, Western
;
Cyclic GMP
;
Dipyridamole
;
Humans
;
Matrix Metalloproteinases
;
Nitric Oxide
;
Permeability
;
Phosphodiesterase Inhibitors
;
Theophylline
;
Trabecular Meshwork
2.A Study on the Relationship Between Mental Health Variables and Physical Activity Variables in the Clinical Group of North Korean Defectors: A Pilot Study
Sung Soo SHIM ; So Hee LEE ; Jung Been LEE ; Yae Eun SEO ; Heon Jeong LEE
Journal of Korean Neuropsychiatric Association 2021;60(3):204-212
Objectives:
This study is designed to extract a representative variable that distinguishes psychiatric patients of North Korean Defectors and a control group by using machine learning based on measured mental health variables and physical activity variables.
Methods:
The physical and mental activity variables of 17 North Korean defectors that previously were hospitalized or received psychiatric outpatient treatment and a control group were compared. The survey focused on mental health variables that included contents related to depression, suicidal risks, post-traumatic stress disorder, anxiety, insomnia, physical symptoms, quality of life, coping skills, social support, and drinking. Physical activity variables included the number of steps walked per day, sleep time, and sleep efficiency were measured by Fitbit.
Results:
The 7th question of the Patient Health Questionnaire-9, “Trouble concentrating on things, such as reading the newspaper or watching television over the past two weeks,” showed the highest gain ratio by 84 percent. Based on the result of the decision tree, this single index may distinguish between the clinical and control groups.
Conclusion
A clinician may conduct a more effective interview with a North Korean defector by identifying in the early stages whether the patient has been having difficulty concentrating on daily tasks during the past two weeks.
3.A Study on the Relationship Between Mental Health Variables and Physical Activity Variables in the Clinical Group of North Korean Defectors: A Pilot Study
Sung Soo SHIM ; So Hee LEE ; Jung Been LEE ; Yae Eun SEO ; Heon Jeong LEE
Journal of Korean Neuropsychiatric Association 2021;60(3):204-212
Objectives:
This study is designed to extract a representative variable that distinguishes psychiatric patients of North Korean Defectors and a control group by using machine learning based on measured mental health variables and physical activity variables.
Methods:
The physical and mental activity variables of 17 North Korean defectors that previously were hospitalized or received psychiatric outpatient treatment and a control group were compared. The survey focused on mental health variables that included contents related to depression, suicidal risks, post-traumatic stress disorder, anxiety, insomnia, physical symptoms, quality of life, coping skills, social support, and drinking. Physical activity variables included the number of steps walked per day, sleep time, and sleep efficiency were measured by Fitbit.
Results:
The 7th question of the Patient Health Questionnaire-9, “Trouble concentrating on things, such as reading the newspaper or watching television over the past two weeks,” showed the highest gain ratio by 84 percent. Based on the result of the decision tree, this single index may distinguish between the clinical and control groups.
Conclusion
A clinician may conduct a more effective interview with a North Korean defector by identifying in the early stages whether the patient has been having difficulty concentrating on daily tasks during the past two weeks.
4.A Simple Method for Generating Cerebral Organoids from Human Pluripotent Stem Cells
Yean Ju HONG ; So been LEE ; Joonhyuk CHOI ; Sang Hoon YOON ; Jeong Tae DO
International Journal of Stem Cells 2022;15(1):95-103
Background and Objectives:
In recent years, brain organoid technologies have been the most innovative advance inneural differentiation research. In line with this, we optimized a method to establish cerebral organoids from feeder-free cultured human pluripotent stem cells. In this study, we focused on the consistent and robust production of cerebral organoids comprising neural progenitor cells and neurons. We propose an optimal protocol for cerebral organoid generation that is applicable to both human embryonic stem cells and human induced pluripotent stem cells.
Methods:
and Results: We investigated formation of neuroepithelium, neural tube, and neural folding by observing the morphology of embryoid bodies at each stage during the cerebral organoid differentiation process. Furthermore, we characterized the cerebral organoids via immunocytochemical staining of sectioned organoid samples, which were prepared using a Cryostat and Vibratome. Finally, we established a routine method to generate early cerebral organoids comprising a cortical layer and a neural progenitor zone.
Conclusions
We developed an optimized methodology for the generation of cerebral organoids using hESCs and hiPSCs. Using this protocol, consistent and efficient cerebral organoids could be obtained from hiPSCs as well as hESCs. Further, the morphology of brain organoids could be analyzed through 2D monitoring via immunostaining and tissue sectioning, or through 3D monitoring by whole tissue staining after clarification.
5.Characterization of Glycosyl Inositol Phosphoceramides from Panax ginseng using Nanospray Tandem Mass Spectrometry
So-Hyun KIM ; Ye-Been LEE ; Yoonho JEONG ; Jae-Yeon CHO ; Hyung-Kyoon CHOI
Natural Product Sciences 2024;30(2):103-116
Korean ginseng (Panax ginseng C. A. Meyer) is one of the most popular medicinal herbs in the world. This plant is known to have many health benefits and contain a wide variety of bioactive components. However, the knowledge on its lipid compound is still far from being fully explored. Although glycosyl inositol phosphoceramides (GIPCs) are the main sphingolipids in plant tissues, GIPCs of P. ginseng are unknown. The present study employed nanoESI-MS n , which generated characteristic fragmentation pattern that were used for the structural identification of P. ginseng GIPCs. In addition to detecting a typical mass fragmentation pattern for GIPC in positive ion mode, novel fragmentation correlating with cleavage of the last carbohydrate and fatty acyl chain of the ceramide moiety was identified. In total, 42 GIPC species were detected in P. ginseng. The major P. ginseng GIPC structure was hexose (R 1 )-hexuronic acid-inositol phosphoceramide, with three types of R 1 (amine, N-acetylamine, or hydroxyl). The most intense peak was found at m/z 1136.3 ([M+H] + ion), corresponding to a GIPC (d18:0/h16:0, R 1 = OH). Only three GIPC subtypes showed significantly different levels in five- and six-year-old P. ginseng tap roots.