Mitochondrial dysfunction and calcium deregulation by the RanBP9-cofilin pathway

Roh, Seung-Eon,Woo, Jung A.,Lakshmana, Madepalli K.,Uhlar, Courtney,Ankala, Vinishaa,Boggess, Taylor,Liu, Tian,Hong, Yun-Hwa,Mook-Jung, Inhee,Kim, Sang Jeong,Kang, David E. The Federation of American Societies for Experimen 2013 The FASEB Journal Vol.27 No.12

<P>Mitochondrial dysfunction and synaptic damage are important features of Alzheimer's disease (AD) associated with amyloid β (Aβ) and tau. We reported previously that the scaffolding protein RanBP9, which is overall increased in brains of patients with AD and in mutant APP transgenic mice, simultaneously promotes Aβ generation and focal adhesion disruption by accelerating the endocytosis of APP and β1-integrin, respectively. Moreover, RanBP9 induces neurodegeneration <I>in vitro</I> and <I>in vivo</I> and mediates Aβ-induced neurotoxicity. Here we show in primary hippocampal neurons that RanBP9 potentiates Aβ-induced reactive oxygen species (ROS) overproduction, apoptosis, and calcium deregulation. Analyses of calcium-handling measures demonstrate that RanBP9 selectively delays the clearance of cytosolic Ca<SUP>2+</SUP> mediated by the mitochondrial calcium uniporter through a process involving the translocation of cofilin into mitochondria and oxidative mechanisms. Further, RanBP9 retards the anterograde axonal transport of mitochondria in primary neurons and decreases synaptic mitochondrial activity in brain. These data indicate that RanBP9, cofilin, and Aβ mimic and potentiate each other to produce mitochondrial dysfunction, ROS overproduction, and calcium deregulation, which leads to neurodegenerative changes reminiscent of those seen in AD.—Roh. S.-E., Woo, J. A., Lakshmana, M. K., Uhlar, C., Ankala, V., Boggess, T., Liu, T., Hong, Y.-H., Mook-Jung, I., Kim, S. J., Kang, D. E. Mitochondrial dysfunction and calcium deregulation by the RanBP9-cofilin pathway.</P>

Response to: Letter to the Editor Regarding “Validation of CT-Based Risk Stratification System for Lymph Node Metastasis in Patients With Thyroid Cancer”

Roh Yun Hwa,Chung Sae Rom 대한영상의학회 2024 Korean Journal of Radiology Vol.25 No.3

Validation of CT-Based Risk Stratification System for Lymph Node Metastasis in Patients With Thyroid Cancer

Roh Yun Hwa,Chung Sae Rom,Baek Jung Hwan,Choi Young Jun,Sung Tae-Yon,Song Dong Eun,Kim Tae Yong,Lee Jeong Hyun 대한영상의학회 2023 Korean Journal of Radiology Vol.24 No.10

Objective: To evaluate the computed tomography (CT) features for diagnosing metastatic cervical lymph nodes (LNs) in patients with differentiated thyroid cancer (DTC) and validate the CT-based risk stratification system suggested by the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) guidelines. Materials and Methods: A total of 463 LNs from 399 patients with DTC who underwent preoperative CT staging and ultrasound-guided fine-needle aspiration were included. The following CT features for each LN were evaluated: absence of hilum, cystic changes, calcification, strong enhancement, and heterogeneous enhancement. Multivariable logistic regression analysis was performed to identify independent CT features associated with metastatic LNs, and their diagnostic performances were evaluated. LNs were classified into probably benign, indeterminate, and suspicious categories according to the K-TIRADS and the modified LN classification proposed in our study. The diagnostic performance of both classification systems was compared using the exact McNemar and Kosinski tests. Results: The absence of hilum (odds ratio [OR], 4.859; 95% confidence interval [CI], 1.593–14.823; P = 0.005), strong enhancement (OR, 28.755; 95% CI, 12.719–65.007; P < 0.001), and cystic changes (OR, 46.157; 95% CI, 5.07–420.234; P = 0.001) were independently associated with metastatic LNs. All LNs showing calcification were diagnosed as metastases. Heterogeneous enhancement did not show a significant independent association with metastatic LNs. Strong enhancement, calcification, and cystic changes showed moderate to high specificity (70.1%–100%) and positive predictive value (PPV) (91.8%–100%). The absence of the hilum showed high sensitivity (97.8%) but low specificity (34.0%). The modified LN classification, which excluded heterogeneous enhancement from the K-TIRADS, demonstrated higher specificity (70.1% vs. 62.9%, P = 0.016) and PPV (92.5% vs. 90.9%, P = 0.011) than the K-TIRADS. Conclusion: Excluding heterogeneous enhancement as a suspicious feature resulted in a higher specificity and PPV for diagnosing metastatic LNs than the K-TIRADS. Our research results may provide a basis for revising the LN classification in future guidelines.

Digital Tomosynthesis versus Conventional Radiography for Evaluating Osteonecrosis of the Femoral Head

Roh Yun Hwa,Lee Seunghun,Ryu Jeong Ah,Kim Yeo Ju,Kim Yeesuk,Bae Jiyoon 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.12

Objective: The aim of this study was to compare the diagnostic performances of digital tomosynthesis (DTS) and conventional radiography in detecting osteonecrosis of the femoral head (ONFH) using computed tomography (CT), as the reference standard and evaluate the diagnostic reproducibility of DTS. Materials and Methods: Forty-five patients (24 male and 21 female; age range, 25–77 years) with clinically suspected ONFH underwent anteroposterior radiography, DTS, and CT. Two musculoskeletal radiologists independently evaluated the presence and type of ONFH. The diagnostic performance of radiography and DTS in detecting the presence of ONFH and determining the types of ONFH were evaluated. The interobserver and intraobserver reliabilities of each imaging modality were analyzed using Cohen’s kappa. Results: DTS had higher sensitivity (89.4%–100% vs. 74.5%–76.6%) and specificity (97.3%–100% vs. 78.4%–83.8%) for ONFH detection than radiography. DTS showed higher performance than radiography in identifying the subtypes of ONFH with statistical significance in one reader (type 1, 100% vs. 30.8%, p = 0.004; type II, 97.1% vs. 73.5%, p = 0.008). The interobserver agreement was excellent for DTS and moderate for radiography (kappa of 0.86 vs. 0.57, respectively). The intraobserver agreement for DTS was higher than that of radiography (kappa of 0.96 vs. 0.69, respectively). Conclusion: DTS showed higher diagnostic performance and reproducibility than radiography in detecting ONFH. DTS may be used as a first-line diagnostic modality instead of radiography for patients suspected of having ONFH.

Increased Circulating Endothelial Microparticles and Carotid Atherosclerosis in Obstructive Sleep Apnea

Yun, Chang-Ho,Jung, Keun-Hwa,Chu, Kon,Kim, So-Hyun,Ji, Ki-Hwan,Park, Hee-Kwon,Kim, Hwan-Cheol,Lee, Soon-Tae,Lee, Sang-Kun,Roh, Jae-Kyu 대한신경과학회 2010 Journal of Clinical Neurology Vol.6 No.2

<P><B>Background and Purpose</B></P><P>Endothelial impairment is a linking mechanism between obstructive sleep apnea (OSA) and cardiovascular diseases. Profiles of endothelial microparticles (EMPs) and endothelial progenitor cells (EPCs) reflect the degree of endothelial impairment. The aims of this study were to measure the levels of EMPs and progenitor cells in OSA, determine the correlations between these factors and OSA severity and the degree of atherosclerosis, and document any changes in these factors after therapy.</P><P><B>Methods</B></P><P>Subjects with (<I>n</I>=82) and without (<I>n</I>=22) OSA were recruited prospectively. We measured the number of colony-forming units (CFU) in cell culture as the endothelial progenitor cell index, and the number of EMPs using flow cytometry with CD31 [platelet endothelial cell adhesion molecule (PECAM)], CD42 (platelet glycoprotein), annexin V, and CD62E (E-selectin) antibodies at baseline and after 4-6 weeks of continuous positive airway pressure (CPAP) therapy. Carotid intima-media thickness (IMT) was regarded as a marker of atherosclerosis.</P><P><B>Results</B></P><P>The levels of PECAM<SUP>+</SUP>CD42<SUP>-</SUP> (<I>p</I><0.001), PECAM<SUP>+</SUP>annexin V<SUP>+</SUP> (<I>p</I><0.001), and E-selectin<SUP>+</SUP> microparticles (<I>p</I>=0.001) were higher in OSA subjects than in non-OSA subjects. The number of CFU did not differ between the two groups. OSA severity independently predicted the levels of PECAM<SUP>+</SUP>CD42<SUP>-</SUP> (<I>p</I>=0.02) and PECAM<SUP>+</SUP>annexin V<SUP>+</SUP> (<I>p</I>=0.004). Carotid IMT was correlated with OSA severity (<I>p</I><0.001), PECAM<SUP>+</SUP>CD42<SUP>-</SUP> (<I>p</I>=0.03), and PECAM<SUP>+</SUP>annexin V<SUP>+</SUP> (<I>p</I>=0.01). Neither OSA severity nor carotid IMT was correlated with either the number of CFU or E-selectin<SUP>+</SUP>. CPAP therapy decreased the occurrence of E-selectin<SUP>+</SUP> (<I>p</I><0.001) in 21 of the OSA subjects, but had no effect on the other microparticles of the number of CFU.</P><P><B>Conclusions</B></P><P>OSA led to the overproduction of EMPs, which moderately correlated with OSA severity and the degree of atherosclerosis, and partly responded to therapy. The endothelial impairment might contribute to future cardiovascular events.</P>

Fabrication of a three-electrode battery using hydrogen-storage materials

Roh, Chi-Woo,Seo, Jung-Yong,Moon, Hyung-Seok,Park, Hyun-Young,Nam, Na-Yun,Cho, Sung Min,Yoo, Pil J.,Chung, Chan-Hwa Elsevier 2015 Journal of Power Sources Vol.280 No.-

<P><B>Abstract</B></P> <P>In this study, an energy storage device using a three-electrode battery is fabricated. The charging process takes place during electrolysis of the alkaline electrolyte where hydrogen is stored at the palladium bifunctional electrode. Upon discharging, power is generated by operating the alkaline fuel cell using hydrogen which is accumulated in the palladium hydride bifunctional electrode during the charging process. The bifunctional palladium electrode is prepared by electrodeposition using a hydrogen bubble template followed by a galvanic displacement reaction of platinum in order to functionalize the electrode to work not only as a hydrogen storage material but also as an anode in a fuel cell. This bifunctional electrode has a sufficiently high surface area and the platinum catalyst populates at the surface of electrode to operate the fuel cell. The charging and discharging performance of the three-electrode battery are characterized. In addition, the cycle stability is investigated.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We design new-concept three-electrode battery using hydrogen as energy carrier. </LI> <LI> Charging process is electrolysis of alkaline electrolyte. </LI> <LI> Discharging process is operation of alkaline fuel cell. </LI> <LI> Hydrogen is stored at bifunctional electrode as metal hydride with charging process. </LI> <LI> Bifunctional electrode acts as electrolysis cathode and fuel cell anode at same time. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Cardioprotective effect of KR-32560, a novel sodium/hydrogen exchanger-1 inhibitor, on ischemia/reperfusion heart injury in rat

Shin Hwa-Sup,Roh Hui-Yul,Jung In-Sang,Park Jung-Woo,Yun Yeo-Pyo,Yi Kyu-Yang,Yoo Sung-eun,Kwon Suk-Hyung 대한약학회 2004 大韓藥學會 總會 및 學術大會 Vol.2004 No.2

한ㆍ일 FTA와 중소기업의 활성화 대책

이윤보(Yun Bo Lee),이동주(Dong Ju Lee),노화봉(Hwa Bong Roh),이병구(Byung Gu Lee) 건국대학교 경제경영연구소 2005 商經硏究 Vol.30 No.1

The FTA between Korea and Japan is going to be signed until the end of 2005, an Korean has been more interested in an area on small-medium business which must be settled without delay. The effect of FTA Korea-japan has two kind of thing which are positive and negative. The side of positive things are that is to create on new opportunity of business by promoting in a industry cooperation with Japan, to be expected to effect on cost reduction in firm which has been depended on import of capital goods and accessories. The other are that is to damage on re-ordered production firm by compete with Japanese firms on short term, to worry about rapidly increased import on country. Therefore we have to consider a counterplan immediately for minimize a negative, for maximize a positive on small-medium business by FTA Korea-Japan.

Case Report : Mycosis Fungoides as an Ichthyosiform Eruption

Kyung Hwa Nam,Jin Park,Jin Seok Hong,Si Gyun Roh,Dae Shick Kim,Seok Kweon Yun 대한피부과학회 2009 Annals of Dermatology Vol.21 No.2

Ichthyosiform eruption as a specific manifestation of mycosis fungoides is very rare and only a few such cases have currently been reported in the medical literature. A 63-year-old Korean man presented with a 4-year history of a pruritic ichthyotic eruption. There was no personal or family history of ichthyosis or atopy. The ichthyosiform skin changes involved the abdomen, arms, thighs and shins. The face, palms and soles were spared. There was no peripheral lymphadenopathy or organomegaly. The typical lesions of mycosis fungoides were not present. The results of the routine investigations were normal or negative. A skin biopsy specimen revealed the findings of early mycosis fungoides. He was successfully treated with photochemotherapy. (Ann Dermatol 21(2) 182~184, 2009)

Risk factors for lower extremity lymphedema after surgery in cervical and endometrial cancer

이중요,Hwa Kyung Byun,임상희,손원정,Yun Ho Roh,Yong Bae Kim 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.3

Objective: Lower extremity lymphedema (LEL) is a well-known adverse effect related to cervical and endometrial cancer (CEC); however, very few studies have elucidated the clinicopathologic risk factors related to LEL. We investigated the incidence and risk factors in patients who received primary surgery and/or adjuvant radiotherapy (RT) or chemotherapy for CEC. Methods: We retrospectively reviewed 2,565 patients who underwent primary surgery following CEC diagnosis between January 2007 and December 2020. LEL diagnosis was based on objective and subjective assessments by experts. We identified important predictors of LEL to construct a nomogram predicting individual risks of LEL. For internal validation of the nomogram, the original data were separated using the split-sample method in a 7:3 ratio of training data and test data. Results: Overall, 858 patients (33.5%) received RT, 586 received external beam RT (EBRT), and 630 received intracavitary RT. During follow-up period, LEL developed in 331 patients, with an overall cumulative 5-year incidence of 13.3%. In multivariate analysis, age at primary treatment, use of docetaxel-based chemotherapy, type of hysterectomy, type of surgical pelvic lymph node (LN) assessment, number of dissected pelvic and para-aortic LNs, and EBRT field were the independent predictors of LEL. We subsequently developed the nomogram showing excellent predictive power for LEL. Conclusion: LEL is associated with various treatment modalities, and their interactions may increase the possibility of occurrences. De-escalation strategies for treatment modalities should be considered to reduce LEL in patients with CEC.