The usefulness and accuracy of sentinel lymph node biopsy using single photon emission computed tomography/computed tomography with 99mTc phytate to detect locoregional lymph node metastases in patients with papillary thyroid carcinoma

Jeonghun Lee,Kuk Young Na,Jandee Lee,Su Jin Lee,Young Sil An,Joon Kee Yoon,Euy Young Soh 대한외과학회 2013 Annals of Surgical Treatment and Research(ASRT) Vol.84 No.4

Purpose: Regional lymph node (LN) metastases are detected in 57?85% of patients with papillary thyroid carcinoma (PTC) and are associated with increased tumor recurrence. However, the management of lymphatic disease in patients with PTC has been ongoing source of debate. We have prospectively assessed the usefulness and accuracy of sentinel LN (SLN) biopsy for the detection of LN metastases in patients with PTC on preoperative imaging using single photon emission computed tomography/computed tomography (SPECT/CT) and 99mTc phytate. Methods: We prospectively assessed 39 patients with PTC who had risk factors for recurrence or with the necessity of intraoperative LN sampling for suspicious LN metastases on preoperative imaging from August 2010 to March 2011. The patients underwent preoperative lymphoscintigraphy and SPETC/CT and intraoperative SLN biopsy (SLNB). Results: 99mTc lymphoscintigraphy and SPECT/CT localized SLN in 38 patients (97.4%), with the gamma probe identifying 2.15 mean SLNs in the lateral neck of the 39 patients. Skip metastasis was found in one patient, and lateral compartment LN metastasis in 17 (43.5%). The sensitivity, specificity, and accuracy of SLNB for lateral compartment LN metastasis were 88.2%, 100%, and 94.8%, respectively. SLNB was more accurate and useful for lateral than for central compartment LN metastasis. Conclusion: SPECT/CT improved SLN detection and anatomical localization compared with lymphoscintigraphy. SLNB in patients with risk factors for recurrence or the necessity of intraoperative LN sampling for suspected LN metastases on preoperative imaging was accurate in detecting LN metastases and may help in deciding whether to perform lateral compartment dissection in patients with PTC.

A multifunctional mesoporous nanocontainer with an iron oxide core and a cyclodextrin gatekeeper for an efficient theranostic platform

Lee, Jeonghun,Kim, Hyunjung,Kim, Seahee,Lee, Hyemi,Kim, Jin,Kim, Namkug,Park, Heon Joo,Choi, Eun Kyoung,Lee, Jin Seong,Kim, Chulhee The Royal Society of Chemistry 2012 Journal of materials chemistry Vol.22 No.28

<P>We report on the dual function of a silica–iron oxide hybrid nanoparticle combined with a stimulus responsive gatekeeper on the surface. Multifunctional hybrid nanoparticles (Fe@Si–DOX–CD–PEG) composed of an Fe<SUB>3</SUB>O<SUB>4</SUB> core, a mesoporous silica shell, and GSH-responsive CD gatekeepers are an excellent platform for anticancer drug delivery and MR imaging. In particular, the CD gatekeepers on the surface of the hybrid nanoparticle play a key role in accommodating anticancer drug molecules in the pore of the silica shell without premature release until CD gatekeepers are cleaved by GSH. We confirmed, from an <I>in vitro</I> study with the A549 cell line, that DOX was released from the internalized carriers due to GSH-mediated cleavage of the CD gatekeeper. Consequently, apoptotic and clonogenic death occurred in the cells treated with Fe@Si–DOX–CD–PEG. The accumulation of Fe@Si–DOX–CD–PEG in the tumors was detected by <I>in vivo</I> MR imaging. The growth of the tumor <I>in vivo</I> was effectively suppressed by the intravenously injected Fe@Si–DOX–CD–PEG. In addition, the results of the <I>in vivo</I> MR imaging reflected the <I>in vivo</I> inhibition of the cancer growth by Fe@Si–DOX–CD–PEG.</P> <P>Graphic Abstract</P><P>Multimodal hybrid nanoparticles composed of a Fe<SUB>3</SUB>O<SUB>4</SUB> core, a mesoporous silica shell, and GSH-responsive CD gatekeepers are an excellent theranostic platform for MR imaging and anticancer drug delivery not only <I>in vitro</I> but also <I>in vivo</I>. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2jm32137h'> </P>

Zerumbone suppresses EGF-induced CD44 expression through the inhibition of STAT3 in breast cancer cells

KIM, SANGMIN,KIL, WON HO,LEE, JEONGMIN,OH, SOO-JIN,HAN, JEONGHUN,JEON, MYEONGJIN,JUNG, TAEWOO,LEE, SE KYUNG,BAE, SOO YOUN,LEE, HYUN CHUL,LEE, JUN HO,YI, HA WOO,KIM, SEOK WON,NAM, SEOK JIN,LEE, JEONG E Spandidos Publications 2014 ONCOLOGY REPORTS Vol.32 No.6

<P>Expression of the CD44 gene is upregulated in breast cancer cells and is correlated with patient survival. Aberrant CD44 expression promotes tumor progression and metastasis. In the present study, we investigated the role of zerumbone (ZER) on regulatory mechanisms of CD44 expression in breast cancer cells. Our results showed that CD44 expression was significantly increased by epidermal growth factor receptor (EGFR) ligands in SKBR3 breast cancer cells. In contrast, EGF-induced CD44 expression was decreased by a MEK1/2 inhibitor, UO126, or STAT3 inhibitor, STAT3 VI, respectively. Notably, ZER downregulated the basal level of CD44 expression in CD44+ breast cancer cells. In addition, the induction of CD44 expression by EGFR ligands, EGF or TGF-α, was markedly decreased by ZER treatment. Finally, we investigated the inhibitory mechanism of ZER on EGF-induced CD44 expression. Our results showed that EGF-induced phosphorylation of STAT3 was completely suppressed by ZER. Collectively, ZER suppressed EGF-induced CD44 expression through inhibition of the STAT3 pathway. Therefore, we suggested that ZER may act as a promising therapeutic drug for the treatment of breast cancer.</P>

Stress Affects Thyroid Stimulating Hormone and Thyroid Hormone in the Patients Who Underwent Thyroidectomy

Lee Jeonghun 대한내분비외과학회 2024 The Koreran journal of Endocrine Surgery Vol.24 No.1

Purpose: For recent decades, there have been many studies on the relationship with thyroid dysfunction and mood disorder, anxiety, or stress, but the results have been inconsistent. Also, few studies have examined the effects of psychological disorder on thyroid function in patients who underwent thyroidectomy. In this study, we investigated the relationship between stress and thyroid dysfunction in such patients. Methods: Twenty-eight patients were enrolled who underwent thyroidectomy from July 2007 to January 2016 and who experienced life events after thyroid surgery. Five patients underwent lobectomy. The mean follow-up period was 49 months. In this retrospective cohort study, thyroid stimulating hormone (TSH) and thyroid hormones (T4, T3) tested periodically were compared with PROC MIXED with SAS v9.4. The stressors were found by open questionnaire during outpatient’s visits. Results: The patients enrolled in this study took 3–8 thyroid function tests during the follow-up period (mean 49 months). Eight patients (28.5%) had mild to moderate hypothyroidism with TSH less than 10 μIU/mL and 14 patients (50.0%) had overt hypothyroidism with TSH >10 μIU/ mL. When the patients were under stress, free T4 decreased and TSH increased after adjusting the effect of decreased T4 (P<0.001), despite identical levothyroxine dose and good compliance. Conclusion: In the patients who underwent thyroidectomy, TSH increased under stress, because of the loss or lack of the compensatory response of thyroid. Therefore, for patients with thyroid cancer under stress, levothyroxine dose and frequency of outpatient visit will be needed to be adjusted during follow-up.

Clinical Outcomes of Simultaneous Resection for Colorectal Cancer and Synchronous Liver Metastases in Elderly versus Non-Elderly: A Retrospective Cohort Study

Jeonghun Lee(김종찬) 대한외과학회 2021 대한외과학회 학술대회 초록집 Vol.2021 No.5

Improved Efficiency of Inverted Organic Light-Emitting Diodes Using Tin Dioxide Nanoparticles as an Electron Injection Layer

Lee, Hyunkoo,Kang, Chan-Mo,Park, Myeongjin,Kwak, Jeonghun,Lee, Changhee American Chemical Society 2013 ACS APPLIED MATERIALS & INTERFACES Vol.5 No.6

<P>We demonstrated highly efficient inverted bottom-emission organic light-emitting diodes (IBOLEDs) using tin dioxide (SnO<SUB>2</SUB>) nanoparticles (NPs) as an electron injection layer at the interface between the indium tin oxide (ITO) cathode and the organic electron transport layer. The SnO<SUB>2</SUB> NP layer can facilitate the electron injection since the conduction band energy level of SnO<SUB>2</SUB> NPs (−3.6 eV) is located between the work function of ITO (4.8 eV) and the lowest unoccupied molecular orbital (LUMO) energy level of typical electron transporting molecules (−2.5 to −3.5 eV). As a result, the IBOLEDs with the SnO<SUB>2</SUB> NPs exhibited a decrease of the driving voltage by 7 V at 1000 cd/m<SUP>2</SUP> compared to the device without SnO<SUB>2</SUB> NPs. They also showed a significantly enhanced luminous current efficiency of 51.1 cd/A (corresponds to the external quantum efficiency of 15.6%) at the same brightness, which is about two times higher values than that of the device without SnO<SUB>2</SUB> NPs. We also measured the angular dependence of irradiance and electroluminescence (EL) spectra in the devices with SnO<SUB>2</SUB> NPs and found that they had a nearly Lambertian emission profile and few shift in EL spectrum through the entire viewing angles, which are considered as remarkable and essential results for the application of OLEDs to display devices.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2013/aamick.2013.5.issue-6/am302787y/production/images/medium/am-2012-02787y_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am302787y'>ACS Electronic Supporting Info</A></P>

Stimulus-Induced Conformational Transformation of a Cyclic Peptide for Selective Cell-Targeting On-Off Gatekeeper for Mesoporous Nanocarriers

Lee, Jeonghun,Oh, Eun-Taex,Song, Jaehun,Kim, Ha Gyeong,Park, Heon Joo,Kim, Chulhee Wiley-VCH Verlag GmbH & Co. KGaA 2017 Chemistry - An Asian Journal Vol. No.

<P>alpha(v)beta(3) Integrin is upregulated on many cancer cells. We designed a dual functional cyclic peptide gatekeeper with a capability of stimuli-responsive conformational transformation which could serve as a selective cell-targeting on-off gatekeeper for mesoporous nanocarriers. The advantage of employing the motif of stimuli-induced conformational transformation of cyclic peptides is that they could be utilized not only as an on-off gatekeeper for the triggered release of cargo drugs but also as a targeting ligand of the carriers to desired cells with their respective binding receptors. The peptide gatekeepers on the surface of nanocarriers exhibited on-off gatekeeping via conformational transformation triggered by intracellular glutathione levels of the cancer cells. The cyclic RGD sequence of the peptide gatekeepers enhanced the intracellular uptake into tumor cells (A549) and the therapeutic efficacy of the nanocarrier.</P>

Camouflaged Adversarial Attack on Object Detector

Jeonghun Kim,Kyungmin Lee,Hyeongkeun Lee,Hunmin Yang,Se-Yoon Oh 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10

The existence of physical-world adversarial examples such as adversarial patches proves the vulnerability of real-world deep learning systems. Therefore, it is essential to develop efficient adversarial attack algorithms to identify potential risks and build a robust system. The patch-based physical adversarial attack has shown its effectiveness in attacking neural network-based object detectors. However, the generated patches are quite perceptible for humans, violating the fundamental assumption of adversarial examples. In this work, we present task-specific loss functions that can generate imperceptible adversarial patches based on camouflaged patterns. First, we propose a constrained optimization method with two camouflage assessment metrics to quantify camouflage performance. Then, we show the regularization with those metrics can help generate the adversarial patches based on camouflage patterns. Furthermore, we validate our methods with various experiments and show that we can generate natural-style camouflaged adversarial patches with comparable attack performance.

Nanotubular Assembly of Amide Dendron and Cucurbiturils

Lee, Jeonghun,Park, Sangkyu,Min, Doohong,Choi, Eun Kyoung,Kim, Chulhee Wiley (John WileySons) 2013 Chemistry, an Asian journal Vol.8 No.12

RAVIP: Real-Time AI Vision Platform for Heterogeneous Multi-Channel Video Stream

( Jeonghun Lee ),( Kwang-il Hwang ) 한국정보처리학회 2021 Journal of information processing systems Vol.17 No.2

Object detection techniques based on deep learning such as YOLO have high detection performance and precision in a single channel video stream. In order to expand to multiple channel object detection in real-time, however, high-performance hardware is required. In this paper, we propose a novel back-end server framework, a real-time AI vision platform (RAVIP), which can extend the object detection function from single channel to simultaneous multi-channels, which can work well even in low-end server hardware. RAVIP assembles appropriate component modules from the RODEM (real-time object detection module) Base to create perchannel instances for each channel, enabling efficient parallelization of object detection instances on limited hardware resources through continuous monitoring with respect to resource utilization. Through practical experiments, RAVIP shows that it is possible to optimize CPU, GPU, and memory utilization while performing object detection service in a multi-channel situation. In addition, it has been proven that RAVIP can provide object detection services with 25 FPS for all 16 channels at the same time.