Effect of composite PEO film containing titanium oxides on the corrosion resistance of Al 6061 alloy

Sung, Dahye,Kim, Donghyun,Park, Jung-Hyun,Kim, Yonghwan,Chung, Wonsub Elsevier 2017 Surface & coatings technology Vol.309 No.-

<P><B>Abstract</B></P> <P>Composite plasma electrolytic oxidation (PEO) was carried out to deposit Ti-oxides directly on a substrate of Al 6061 alloy. A TiO<SUB>2</SUB> (anatase)- and Al<SUB>2</SUB>O<SUB>3</SUB>-dense composite PEO film is generated on the substrate, and the corrosion resistance was examined by electrochemical analyses: potentio-dynamic polarization (PP), and electrochemical impedance spectroscopy (EIS) using an equivalent electrical circuit model. In addition, surface and cross-sectional morphologies were observed to confirm the dependence of pore size on treatment time. Using a current density of 10A/dm<SUP>2</SUP> applied for up to 30min, the PEO film produced is denser, more continuous, and has smaller pores in comparison to conventional PEO specimens. In addition, the corrosion resistance observed in the electrochemical tests is enhanced for the composite PEO film in comparison to conventional PEO treatment.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We fabricated the Ti-oxides composite coating layer on aluminium alloy by PEO process. </LI> <LI> A diffusion resistance was removed by composite PEO with direct deposition of Ti-oxides. </LI> <LI> The size of pores was significantly decreased compared with the conventional PEO. </LI> </UL> </P>

Comparison of progression-free survival outcome of sentinel node biopsy without ultrastaging versus lymphadenectomy in endometrial cancer: a propensity-matched analysis

Dahye Lee,김유나,Sang Hyun Cho,Hye soo Yoon,김영태,김성훈,김상운 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.6

Objective: We aimed to investigate the oncologic outcomes of patients with endometrial cancer who underwent sentinel lymph node (SLN) biopsy without ultrastaging compared with that of those who underwent lymphadenectomy (LND). Methods: Patients with endometrial cancer who underwent staging with SLN biopsy or LND during 2006 – 2021 were analyzed using propensity score matching (PSM). SLN metastasis was examined using hematoxylin and eosin staining, without ultrastaging. Progression-free survival (PFS) was compared between the two groups before and after PSM using age, histology, and stage as covariates. Clinical variables such as recurrence patterns and lymphatic complications, were assessed. Results: After excluding 213 patients who underwent validation LND with SLN biopsy, 902 were identified. The demographics of the remaining patients differed according to histology, myometrial invasion depth, and stage. Lymph node metastasis was less frequent in the SLN group than in the LND group (9.4% vs. 3.8%, p=0.004). The recurrence rates within 2 years were lower in the SLN group. The SLN group exhibited significantly superior 2-year and overall PFS than the LND group. Among patients with uterus-confined disease, overall PFS was favorable for SLN biopsy. After matching, differences in PFS were no longer observed, although the lymphocele and lymphedema rates were significantly lower in the SLN group. Conclusion: In patients with endometrial cancer, SLN biopsy without ultrastaging did not compromise survival outcomes and was associated with significantly reduced lymphatic complication rates compared with LND. Therefore, SLN biopsy can be recommended for patients with endometrial cancer without definitive preoperative evidence of distant metastasis.

S-137 Comparison of tenofovir therapy between nucleos(t)ide-naive and -resistant chronic hepatitis B

( Dahye Kim ),( Joong Gi Bae ),( Hyun Seong Lee ),( Young Min Shin ),( Kyung Hye Park ),( Byung Uk Lee ),( Jae Ho Park ),( Byung Gyu Kim ),( Seok Won Jung ),( In Du Jeong ),( Sung-jo Bang ),( Jung Woo 대한내과학회 2016 대한내과학회 추계학술대회 Vol.2016 No.1

Background:?Tenofovir (TDF) is a nucleotide analog used in the treatment of chronic hepatitis B (CHB) infection regardless of whether nucleos(t)ide (NA) resistance. Little data are available on the comparison of TDF therapy between NA-naive and NA-resistant chronic hepatitis B (CHB) patients.?Methods:?Of the 735 eligible patients, 466 were NA-naive and 269 were resistance to NA therapy prior to TDF rescue therapy. A matched study population was constructed to compare the antiviral efficacy of TDF therapy by a propensity score analysis. The primary endpoint was a virological response (VR), defined as an HBV DNA level of <12 IU/mL.?Results: Two hundreds fifty-four CHB patients were selected after matching propensity score with 1:1 ratio. VR occurred in 204 patients (111 patients belonged to the NA-naive group and 93 patients belonged to the NA-resistant group) during the treatment period. There was statistically significant difference in VR between the NA-naive group and the NA-resistant group (87.4% vs. 73.2%; p=0.005). Partial virologic response rates were also differ between both groups (37.8% and 55.1% in the NA-naive group and the NA-resistant group, respectively; p=0.006). ALT normalization rates did not differ between both groups (91.0% and 93.0% in the NA-naive group and the NA-resistant group, respectively; p=0.770). During TDF therapy, 17.5% (14 of 80) of patients in the NA-naive group, and 13.0% (10 of 77) of patients in the NA-resistant group achieved HBeAg seroconversion, respectively (p=0.432). Multivariate logistic regression analysis using selected baseline factors identified absolute HBV-DNA levels at baseline (p<0.001; OR, 0.755; 95% CI, 0.683-0.834), NA-resistant group (p<0.001; OR, 1.655; 95% CI, 1.249-2.194), and HBeAg positivity (p<0.001; OR, 0.531; 95% CI, 0.383-0.737) as factors showing significant association with VR.?Conclusions:?TDF therapy would be more superior in NA-naive patients than NA-resistant chronic hepatitis B patients. The lower HBV DNA levels at baseline and HBeAg-negative CHB patients also were significantly associated with virologic response.

Ginsenoside Rg3-enriched red ginseng extract inhibits platelet activation and in vivo thrombus formation

Dahye Jeong,Muhammad Irfan,Sung-Dae Kim,Suk Kim,Jun-Hwan Oh,Chae-Kyu Park,Hyun-Kyoung Kim,Man Hee Rhee 고려인삼학회 2017 Journal of Ginseng Research Vol.41 No.4

Background: Korean Red Ginseng has been used for several decades to treat many diseases, enhancing both immunity and physical strength. Previous studies have documented the therapeutic effects of ginseng, including its anticancer, antiaging, and anti-inflammatory activities. These activities are mediated by ginsenosides present in the ginseng plant. Ginsenoside Rg3, an effective compound from red ginseng, has been shown to have antiplatelet activity in addition to its anticancer and anti-inflammatory activities. Platelets are important for both primary hemostasis and the repair of the vessels after injury; however, they also play a crucial role in the development of acute coronary diseases. We prepared ginsenoside Rg3-enriched red ginseng extract (Rg3-RGE) to examine its role in platelet physiology. Methods: To examine the effect of Rg3-RGE on platelet activation in vitro, platelet aggregation, granule secretion, intracellular calcium ([Ca<SUP>2+</SUP>]i) mobilization, flow cytometry, and immunoblot analysis were carried out using rat platelets. To examine the effect of Rg3-RGE on platelet activation in vivo, a collagen plus epinephrine-induced acute pulmonary thromboembolism mouse model was used. Results: We found that Rg3-RGE significantly inhibited collagen-induced platelet aggregation and [Ca<SUP>2+</SUP>]<SUP>i</SUP> mobilization in a dose-dependent manner in addition to reducing ATP release from collagen-stimulated platelets. Furthermore, using immunoblot analysis, we found that Rg3-RGE markedly suppressed mitogen-activated protein kinase phosphorylation (i.e., extracellular stimuli-responsive kinase, Jun Nterminal kinase, p38) as well as the PI3K (phosphatidylinositol 3 kinase)/Akt pathway. Moreover, Rg3-RGE effectively reduced collagen plus epinephrine-induced mortality in mice. Conclusion: These data suggest that ginsenoside Rg3-RGE could be potentially be used as an antiplatelet therapeutic agent against platelet-mediated cardiovascular disorders.

1-Methyl-3-octylimidazolium tetrafluoroborate/AgO nanoparticles composite membranes for facilitated gas transport

Sang Wook Kang,Dahye Ji 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.2

AgO nanoparticles (NPs) were generated in ionic liquid 1-methyl-3-octylimidazolium tetrafluoroborate (Moim+BF4 −). The formation of Ag NPs was attributable to the favorable interaction between the surface of particles and counteranions of ionic liquid. The generated AgO nanoparticles in Moim+BF4 − were confirmed by TEM, and the average size was 40 nm. Coordinative interactions of AgO NPs with Moim+BF4 − were investigated by FT-Raman spectroscopy. The prepared Moim+BF4 −/Ag NPs composites were utilized for CO2 separation membrane, and consequently, CO2 separation performance for composite membranes was improved compared with neat Moim+BF4 −. The ideal selectivity for CO2/N2 was 23.4 with a CO2 permeance of 18.7GPU was observed, while the neat Moim+BF4 − membrane showed a selectivity of 15.9 and a CO2 permeance of 12.7GPU.

Endoscopic Management of Pancreaticopleural Fistula in a Child with Hereditary Pancreatitis

Dahye Lee,Eun Joo Lee,Ju Whi Kim,Jin Soo Moon,Yong-Tae Kim,Jae Sung Ko 대한소아소화기영양학회 2019 Pediatric gastroenterology, hepatology & nutrition Vol.22 No.6

Pancreaticopleural fistula (PPF) a fistulous connection between the pancreas and pleural space due to prolonged chronic pancreatitis (CP). PPF is a very rare complication which presents in 0.4% of chronic pancreatitis cases, especially among children. We report a case involving a 3-year-old boy who presented with pleural effusion caused by a PPF, a complication of hereditary pancreatitis, which was, for the first time in Korea, successfully managed with endoscopic treatment. Chest radiography and computed tomography showed massive pleural effusion. Percutaneous catheter drainage was performed. High amylase levels were observed in the pleural fluid and serum, suggesting PPF. The patient was managed with bowel rest and octreotide infusion. Endoscopic retrograde cholangiopancreatography revealed CP, and pleural effusion was successfully managed with stent placement. PRSS1 genetic screening revealed R122H mutation.

Identification of two novel Duchenne muscular dystrophies mutations in patients with Becker muscular dystrophy

Kim, Dahye,Kim, Yoon-Myung,Seo, Go Hun,Kim, Gu Hwan,Yoo, Han Wook,Yum, Mi-Sun,Ko, Tae-Sung,Lee, Beom Hee Korean Society of Medical Genetics and Genomics 2017 대한의학유전학회지 Vol.14 No.2

Duchenne and Becker muscular dystrophies (DMD and BMD, respectively) are X-linked neuromuscular disorders characterized by progressive muscle weakness and severe skeletal muscle degeneration. BMD is a milder form with a later onset. Patients with BMD tend to survive much longer than those with DMD. The differentiation between DMD and BMD is important in the genetic counseling of affected patients and their families. Since muscle biopsies are invasive procedures, the differential diagnosis of BMD and DMD is often dependent on the mutation identified in the DMD gene in affected patients. However, when a novel DMD mutation is identified, the differential diagnosis should be based on muscle biopsy findings with other clinical findings. Here we describe two Korean patients with BMD confirmed by muscle biopsy and genetic testing. Two novel exonic deletions in the DMD gene were identified.

차량용 2D 라이다를 이용한 특징정보 기반 확장표적추적 기법

함다혜(Dahye Ham),조형찬(Hyung-Chan Cho),윤유정(Yoo-Jung Yoon),나원상(Won-Sang Ra),한슬기(Seul-Ki Han) 대한전기학회 2021 전기학회논문지 Vol.70 No.1

This paper deals with the design problem of an extended target tracking filter using automotive 2D LIDAR. As a practical way to reduce the dimensionality of the LIDAR point cloud data and to extract an important target feature from it, the Hough transform is applied and the corresponding measurement equation is modeled. It is well-known that the pattern of the LIDAR point cloud varies with the relative geometry due to occlusion, which may leads the severe performance degradation in target tracking. To cope with this problem, a multiple model filter is designed by considering the measurement acquisition hypotheses on the target feature. Through the experiments in real-driving condition, the superior performance of the proposed filter over the existing method is demonstrated.

실리카 나노입자에 도입된 로다민 화학센서 개발과 금속이온 검출

신상빈(Sang Bin Shin),이다혜(Dahye Lee),허기석(Gisuk Heo),도정윤(Jung Yun Do) 한국고분자학회 2020 폴리머 Vol.44 No.6

실리카 결합 로다민 화학센서 물질을 개발하고 수용액에 분산시켜 금속이온의 검출 특성 연구를 하였다. 락톤 구조와 락탐 구조를 갖는 로다민 유도체가 결합된 2종의 실리카 나노입자를 제조하였고 pH와 다양한 금속 이온에 노출시켜 입자의 색 변화를 관찰하였다. 실리카로 구성된 내부와 로다민으로 결합된 외부를 갖는 이중구조의 나노입자를 설계하였고, 테트라에톡시 실란과, 실란이 도입된 로다민 유도체를 한 반응기 내에서 단계적으로 도입하는 방법으로 수백 나노 크기의 구형의 실리카 입자를 제조하였다. 금속이온(Hg<SUP>2+</SUP>, Fe<SUP>3+</SUP>, Al<SUP>3+</SUP>)에 선택적 결합력을 갖는 로다민 유도체의 특성은 실리카 입자에 결합된 상태에서도 유사하게 관찰되었다. 로다민의 락톤 작용기는 실리카표면에서 부분적인 고리열림반응이 진행되어 색상을 갖는 실리카 형성을 하였고 센서물질로서 적합하지 않았다. 반면, 락탐 구조의 로다민은 실리카 표면에서 안정되어 무색의 입자 상태를 유지하였고 이온 검출에서 큰 소광비에 따른 뚜렷한 변색 특성을 보였다. The preparation of silica-supported rhodamine chemosensors is described. Metal sensing properties are collected as the silica sensors dispersed into aqueous solution. Rhodamine derivatives with lactone and lactam structure on the silica surface were characterized in the condition of pH and with several metal ions. A double layered structure, composed of silica core and rhodamine shell, was achieved in one-pot synthesis of nano-sized silica particles through controlled addition of tetraethoxysilane and silane-bound rhodamines. Color change of the silica particle was observed from colorless to pink, as exposed on Hg<SUP>2+</SUP>, Fe<SUP>3+</SUP>, and Al<SUP>3+</SUP>. The lactone moiety of a rodamine derivative was partially hydrolyzed on the silica surface to exhibit pale color while the lactam was stable to maintain colorless turn-off state, leading to large extinction ratio in sensing.

Water soluble tomato concentrate regulates platelet function via the mitogen-activated protein kinase pathway

Jeong, Dahye,Irfan, Muhammad,Saba, Evelyn,Kim, Sung-Dae,Kim, Seung-Hyung,Rhee, Man Hee The Korean Society of Veterinary Science 2016 大韓獸醫學會誌 Vol.56 No.2

Tomato extract has been shown to exert antiplatelet activity in vitro and to change platelet function ex vivo, but with limitations. In this study, antiplatelet activity of water soluble tomato concentrate (Fruitflow I) and dry water soluble tomato concentrate (Fruitflow II) was investigated using rat platelets. Aggregation was induced by collagen and adenosine diphosphate and granule-secretion, $[Ca^{2+}]_i$, thromboxane B2, cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) levels were examined. The activation of integrin ${\alpha}_{IIb}{\beta}_3$ and phosphorylation of signaling molecules, including mitogen-activated protein kinase (MAPK) and PI3K/Akt, were investigated by flow cytometry and immunoblotting, respectively. Prothrombin time (PT) and activated partial thromboplastin time (aPTT) were examined. Moreover, in vivo thrombus weight was tested by an arteriovenous shunt model. Fruitflow I and Fruitflow II significantly inhibited agonist induced platelet aggregation, adenosine triphosphate and serotonin release, $[Ca^{2+}]_i$, and thromboxane B2 concentration, while having no effect on cAMP and cGMP levels. Integrin ${\alpha}_{IIb}{\beta}_3$ activation was also significantly decreased. Moreover, both concentrates reduced phosphorylation of MAPK pathway factors such as ERK, JNK, P38, and PI3K/Akt. In vivo thrombus formation was also inhibited. Taken together, these concentrates have the potential for ethnomedicinal applications to prevent cardiovascular ailments and can be used as functional foods.