1.Distribution of Free Radicals in Reperfusion Injury after Transient Brain Ischemia.
Eunkyoung KWAK ; Hyungho SUH ; Jiyoung PARK ; Yunsup KUM ; Taein PARK ; Jungwan KIM ; Yoonkyung SOHN
Korean Journal of Pathology 2000;34(11):893-900
Free radicals are known as an important factor which may act on reperfusion injury after transient or permanent brain ischemia. Numerous studies about cytotoxic function of free radical have been done. Most of these studies demonstrate the function of free radical in reperfusion injury by using radical scavenger or antioxidant as inhibitor of radicals. We used a modification of Karnovsky's Mn2 /diaminobenzidine (DAB) technique to demonstrate intravascular free radicals following transient occlusion and reperfusion of one middle cerebral artery in Sprague-Dawley rats. The MCA was occluded for 2 hours using an intraluminal suture method. The reperfusion time after transient ischemia was 1 hour, 6 hours, and 24 hours, respectively. Animals were perfused transcardially with solution containing Mn2 and DAB. After DAB perfusion, the brains were removed promptly, sectioned in frozen, and stained with methylene blue for light microscopic examination. Upon light microscopic examination, free radicals were confined within intravascular lumen and the amount of deposits increased according to the duration of reperfusion. Upon electron microscopic examination, free radicals were located in nuclear membrane and membrane of mitochondria and RER, and demonstrated as electron dense deposits. In addition, cell processes of the neuron revealed an electron dense deposits beneath the inner side of the membrane. In conclusion, free radicals demonstrated in the reperfusion injury area indicate that free radical acts as an important cytotoxic factor. Intracellular localization of free radicals may explain the relationship between free radical and delayed neuronal injury.
Animals
;
Brain Ischemia*
;
Brain*
;
Free Radicals*
;
Ischemia
;
Membranes
;
Methylene Blue
;
Middle Cerebral Artery
;
Mitochondria
;
Neurons
;
Nuclear Envelope
;
Perfusion
;
Rats, Sprague-Dawley
;
Reperfusion Injury*
;
Reperfusion*
;
Sutures
2.Waldenstrom's macroglobulinemia associated with eosinophilia.
Eunkyoung YOU ; Kyung Sam CHO ; Tae Sung PARK
Blood Research 2013;48(1):8-8
No abstract available.
Eosinophilia
;
Waldenstrom Macroglobulinemia
3.Waldenstrom's macroglobulinemia associated with eosinophilia.
Eunkyoung YOU ; Kyung Sam CHO ; Tae Sung PARK
Blood Research 2013;48(1):8-8
No abstract available.
Eosinophilia
;
Waldenstrom Macroglobulinemia
4.Sleep Tracking of Two Smartwatches Against Self-Reported Logs for Circadian Rhythm and Sleep Quality Assessment in Healthy Adults
Ji-Eun PARK ; Jayeun KIM ; Hoseok KIM ; Eunkyoung AHN ; Kyuhyun YOON
Journal of Sleep Medicine 2025;22(1):8-16
Although many wearable devices are used to assess sleep, their accuracy remains controversial. This study aimed to investigate the accuracy of the Actiwatch, a research-grade device, and the Fitbit, a consumer-grade device, against sleep diaries to assess sleep patterns. Methods: Twenty participants wore Fitbit and Actiwatch for two weeks and tracked their sleep patterns using sleep diaries. Total sleep time (TST), time-in-bed (TIB), sleep efficiency (SE), sleep onset latency (SOL), and wake after sleep onset (WASO) from the two devices and sleep diaries were analyzed using analysis of variance and Bland-Altman analysis. Results: The TIB measured by the sleep log, Fitbit, and Actiwatch were 420.9 minutes, 417.3 minutes, and 567.4 minutes, respectively. Compared to the sleep log, the Fitbit underestimated TST, TIB, and SE, with significant differences observed for TST (p<0.001) and SE (p<0.001), but not for TIB. The Actiwatch overestimated TIB (p<0.001) and TST (p=0.02) and underestimated SE (p<0.001) compared to the sleep log. The difference between the Fitbit and Actiwatch was significant for TST, TIB, and SE (all p<0.001). Conclusions: The Fitbit showed a smaller difference than the Actiwatch when compared with the sleep logs. The Fitbit could be used as a tool to assess sleep patterns in the clinic as well as in daily life.
5.Sleep Tracking of Two Smartwatches Against Self-Reported Logs for Circadian Rhythm and Sleep Quality Assessment in Healthy Adults
Ji-Eun PARK ; Jayeun KIM ; Hoseok KIM ; Eunkyoung AHN ; Kyuhyun YOON
Journal of Sleep Medicine 2025;22(1):8-16
Although many wearable devices are used to assess sleep, their accuracy remains controversial. This study aimed to investigate the accuracy of the Actiwatch, a research-grade device, and the Fitbit, a consumer-grade device, against sleep diaries to assess sleep patterns. Methods: Twenty participants wore Fitbit and Actiwatch for two weeks and tracked their sleep patterns using sleep diaries. Total sleep time (TST), time-in-bed (TIB), sleep efficiency (SE), sleep onset latency (SOL), and wake after sleep onset (WASO) from the two devices and sleep diaries were analyzed using analysis of variance and Bland-Altman analysis. Results: The TIB measured by the sleep log, Fitbit, and Actiwatch were 420.9 minutes, 417.3 minutes, and 567.4 minutes, respectively. Compared to the sleep log, the Fitbit underestimated TST, TIB, and SE, with significant differences observed for TST (p<0.001) and SE (p<0.001), but not for TIB. The Actiwatch overestimated TIB (p<0.001) and TST (p=0.02) and underestimated SE (p<0.001) compared to the sleep log. The difference between the Fitbit and Actiwatch was significant for TST, TIB, and SE (all p<0.001). Conclusions: The Fitbit showed a smaller difference than the Actiwatch when compared with the sleep logs. The Fitbit could be used as a tool to assess sleep patterns in the clinic as well as in daily life.
6.Sleep Tracking of Two Smartwatches Against Self-Reported Logs for Circadian Rhythm and Sleep Quality Assessment in Healthy Adults
Ji-Eun PARK ; Jayeun KIM ; Hoseok KIM ; Eunkyoung AHN ; Kyuhyun YOON
Journal of Sleep Medicine 2025;22(1):8-16
Although many wearable devices are used to assess sleep, their accuracy remains controversial. This study aimed to investigate the accuracy of the Actiwatch, a research-grade device, and the Fitbit, a consumer-grade device, against sleep diaries to assess sleep patterns. Methods: Twenty participants wore Fitbit and Actiwatch for two weeks and tracked their sleep patterns using sleep diaries. Total sleep time (TST), time-in-bed (TIB), sleep efficiency (SE), sleep onset latency (SOL), and wake after sleep onset (WASO) from the two devices and sleep diaries were analyzed using analysis of variance and Bland-Altman analysis. Results: The TIB measured by the sleep log, Fitbit, and Actiwatch were 420.9 minutes, 417.3 minutes, and 567.4 minutes, respectively. Compared to the sleep log, the Fitbit underestimated TST, TIB, and SE, with significant differences observed for TST (p<0.001) and SE (p<0.001), but not for TIB. The Actiwatch overestimated TIB (p<0.001) and TST (p=0.02) and underestimated SE (p<0.001) compared to the sleep log. The difference between the Fitbit and Actiwatch was significant for TST, TIB, and SE (all p<0.001). Conclusions: The Fitbit showed a smaller difference than the Actiwatch when compared with the sleep logs. The Fitbit could be used as a tool to assess sleep patterns in the clinic as well as in daily life.
7.Impact of Omicron-Variant SARS-CoV-2 Infection on Depression and Anxiety: A Community-Based Study in Korea
Youngsook KWON ; Jina PARK ; Eunkyoung AN ; Sukyoung JUNG ; Kukju KWEON
Psychiatry Investigation 2024;21(4):415-421
Objective:
This study seeks to evaluate the association between the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the severity of depression and anxiety in the Korean community during the period dominated by the Omicron variant.
Methods:
We used data from the 2022 Daejeon Mental Health Survey, involving data of 985 participants aged 19–69 years. The data collected included SARS-CoV-2 infection experience, days post-infection, and depression and anxiety symptoms evaluated using the Patient Health Questionnaire-9 and the Generalized Anxiety Disorder Questionnaire-7, respectively. Additionally, physical health, social activity status, and sociodemographic characteristics such as gender, age, marital status, educational level, and household income were collected. The association between SARS-CoV-2 infection and depression and anxiety were examined. Further analyses explored association between days post- infection and the severity of depression and anxiety.
Results:
There was no significant correlation between SARS-CoV-2 infection and depression and anxiety in the overall population. Notably, participants under 50 years of age exhibited a transient worsening of depression and anxiety, followed by a decrease in symptoms within 40 days. Participants aged 51 years and older showed no significant change in depression and anxiety.
Conclusion
This study discerned transient effects of Omicron variant infection on depression and anxiety, particularly in younger individuals. A prospective study encompassing a larger sample size is imperative to investigate the influence of SARS-CoV-2 infection on depression and anxiety.
8.Expression of Inducible Nitric Oxide Synthase and Nitric Oxide Mediated Apoptosis in Neuronal PC12 Cells after Lipopolysaccharide/Tumor Necrosis Factor-/Interferon- Treatment.
Jiyeon KIM ; Jiyoung KIM ; Kuseong KANG ; Eunkyoung KWAK ; Jiyoung PARK ; Taein PARK ; Yoonkyung SOHN
Korean Journal of Pathology 2002;36(4):249-256
BACKGROUND: Inducible nitric oxide synthase (iNOS) has been detected in a number of pathologic conditions in the central nervous system. This study was investigated the patterns of iNOS expression in the neuronal PC12 cell and the effects of nitric oxide on the apoptosis of PC12 cells. METHODS: The stimulating agents for induction of iNOS expression in PC12 cells were bacterial lipopolysaccharide (LPS), tumor necrosis factor-alpha (TNF-), and interferon-gamma (IFN-). RESULTS: The expression iNOS mRNA and protein in PC12 cells stimulated with LPS/TNF-/IFN- were profoundly increased. The expression of iNOS mRNA arose at 6 hours, peaked at 12 hours, and declined to 48 hours after LPS/TNF-/ IFN- treatment. iNOS protein was increased up to 24 hours in LPS/TNF-/IFN- treated PC12 cells while the expression of nNOS was unaffected. Accumulation of NO derivatives in the culture media was markedly increased at least at up to 48 hours after LPS/TNF-/IFN- treatment. The induction of iNOS expression and NO production in differentiated PC12 cells was correlated with apoptotic cell death judged by transmission electron microscopy and DNA fragmentation from the results of the Terminal deoxynucleotidyl-transferase-mediated dUDP biotin nick end-labeling (TUNEL) method. After treatment with NOS inhibitor, N-monomethylarginine (NMMA), a profound decrease in NO production by LPS/TNF-/IFN- treated PC12 cells was noted. And the LPS/TNF-/IFN- induced apoptosis was prevented by the NMMA treatment. CONCLUSIONS: From the above results it is concluded that the expression of iNOS in differentiated PC12 cells is induced by the combined application of LPS, TNF-, and IFN-. And the apoptosis of cultured PC12 cells is mediated by iNOS-derived NO.
Animals
;
Apoptosis*
;
Biotin
;
Cell Death
;
Central Nervous System
;
Culture Media
;
DNA Fragmentation
;
Interferon-gamma
;
Microscopy, Electron, Transmission
;
Necrosis*
;
Neurons*
;
Nitric Oxide Synthase Type II*
;
Nitric Oxide*
;
PC12 Cells*
;
RNA, Messenger
;
Tumor Necrosis Factor-alpha
9.A Case of Ceftazidime-Nonsusceptible Burkholderia pseudomallei Infection.
Eunkyoung YOU ; Mi Jeong SEO ; Young Jin KIM ; Myung Jae PARK ; Hee Joo LEE
Laboratory Medicine Online 2015;5(4):219-222
Melioidosis, which is an infectious disease caused by Burkholderia pseudomallei, is prevalent mostly in Southeast Asia and northern Australia; it can progress to abscess formation, pneumonia and sepsis, and ultimately cause death. A 66-yr-old male patient with diabetes mellitus was hospitalized for sepsis 3 months after coming back from Cambodia, and B. pseudomallei was identified from the blood culture. The B. pseudomallei strain was found to be susceptible to carbapenem, and non-susceptible to trimethoprim/sulfamethoxazole and ceftazidime. Although the patient was treated with carbapenem, to which the strain was susceptible, the bacteremia persisted, and progressed to septic shock and pneumonia, and eventually to acute respiratory distress syndrome (ARDS). The patient died on the 12th day of hospitalization. This study, which reports the first case of ceftazidime-nonsusceptible B. pseudomallei in Korea, indicates the importance of B. pseudomallei infection, which is highly likely to be imported to Korea, and discuss its clinical progress, which can lead to fatality.
Abscess
;
Asia, Southeastern
;
Australia
;
Bacteremia
;
Burkholderia pseudomallei*
;
Burkholderia*
;
Cambodia
;
Ceftazidime
;
Communicable Diseases
;
Diabetes Mellitus
;
Hospitalization
;
Humans
;
Korea
;
Male
;
Melioidosis
;
Pneumonia
;
Respiratory Distress Syndrome, Adult
;
Sepsis
;
Shock, Septic