Validation of an Analytical Method for the Determination of Amitraz and Pymetrozine in Organic Farming Materials using QuEChERS Extraction and Liquid Chromatography-tandem Mass Spectrometry

SoHee Park,Hyejin Park,ChaiUk Lim,Kyungeun Yu,Han Sol Lee,Eun Joo Baek,Dogyung Oh,Namkuk Kim,Seong Hun Lee,Sung-Hee Hong 한국농약과학회 2023 한국농약과학회 학술발표대회 논문집 Vol.2023 No.11

Cutoff Values for Diagnosing Hepatic Steatosis Using Contemporary MRI-Proton Density Fat Fraction Measuring Methods

Park Sohee,Kwon Jae Hyun,김소연,Kang Ji Hun,Chung Jung Il,Jang Jong Keon,Jang Hye Young,Shim Ju Hyun,Lee Seung Soo,Kim Kyoung Won,Song Gi-Won 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.12

Objective: To propose standardized MRI-proton density fat fraction (PDFF) cutoff values for diagnosing hepatic steatosis, evaluated using contemporary PDFF measuring methods in a large population of healthy adults, using histologic fat fraction (HFF) as the reference standard. Materials and Methods: A retrospective search of electronic medical records between 2015 and 2018 identified 1063 adult donor candidates for liver transplantation who had undergone liver MRI and liver biopsy within a 7-day interval. Patients with a history of liver disease or significant alcohol consumption were excluded. Chemical shift imaging-based MRI (CS-MRI) PDFF and high-speed T2-corrected multi-echo MR spectroscopy (HISTO-MRS) PDFF data were obtained. By temporal splitting, the total population was divided into development and validation sets. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic performance of the MRI-PDFF method. Two cutoff values with sensitivity > 90% and specificity > 90% were selected to rule-out and rule-in, respectively, hepatic steatosis with reference to HFF ≥ 5% in the development set. The diagnostic performance was assessed using the validation set. Results: Of 921 final participants (624 male; mean age ± standard deviation, 31.5 ± 9.0 years), the development and validation sets comprised 497 and 424 patients, respectively. In the development set, the areas under the ROC curve for diagnosing hepatic steatosis were 0.920 for CS-MRI-PDFF and 0.915 for HISTO-MRS-PDFF. For ruling-out hepatic steatosis, the CS-MRI-PDFF cutoff was 2.3% (sensitivity, 92.4%; specificity, 63.0%) and the HISTO-MRI-PDFF cutoff was 2.6% (sensitivity, 88.8%; specificity, 70.1%). For ruling-in hepatic steatosis, the CS-MRI-PDFF cutoff was 3.5% (sensitivity, 73.5%; specificity, 88.6%) and the HISTO-MRI-PDFF cutoff was 4.0% (sensitivity, 74.7%; specificity, 90.6%). Conclusion: In a large population of healthy adults, our study suggests diagnostic thresholds for ruling-out and ruling-in hepatic steatosis defined as HFF ≥ 5% by contemporary PDFF measurement methods.

Aetiology of cancer in Asia.

Park, Sohee,Bae, Jisuk,Nam, Byung-Ho,Yoo, Keun-Young Asian Pacific Organization for Cancer Prevention 2008 Asian Pacific journal of cancer prevention Vol.9 No.3

<P>Cancer has become the leading cause of death in many Asian countries. There is an increasing trend in breast, prostate and colon cancers, which are considered as typical of economically developed countries. Although breast and prostate cancer rates are still lower than in western countries, they are particularly rapidly increasing. In this paper, we review recently published literature to identify important etiologic factors affecting the cancer risk in Asian populations. Infectious agents such as Helicobacter pylori, hepatitis B and C viruses, and human papillomavirus were shown to be associated with elevated risks of stomach, liver and cervical cancer, respectively. Tobacco smoking was shown to be significantly associated with higher lung cancer risk and moderately increased all cancer risk. Excessive alcohol drinking appeared to increase the risk of colorectal cancer in Japanese and breast cancer in the Korean population. Betel nut chewing was associated with higher risk of oral and esophageal cancer. In terms of diet, various studies have demonstrated that high caloric and fat intake was associated with breast cancer risk, salted food intake with stomach cancer, aflatoxin B1 with liver cancer, and low fruits and vegetables intake with breast and lung cancer. Environmental exposure to indoor and outdoor air pollution, arsenic, radon, asbestos and second hand smoke was shown to increase the lung cancer risk. Reproductive factors such as late age at first childbirth, early menarche, late menopause, oral contraceptive intake, and short duration of lifetime lactation were shown to be associated with breast and/or colorectal cancer. Cancer has clearly become an emerging health threat in Asia and cancer control programs should be actively implemented and evaluated in this region. Various strategies for cancer control have been developed in some Asian countries, including the set-up of national cancer registries, cancer screening programs, education programs for health behavior change, eradication of Helicobacter pylori and vaccination for hepatitis B and C viruses, and human papilloma virus high risk forms. However, more attention should also be paid to low- and medium-resource Asian countries where cancer incidence rates are high, but neither intensive research on cancer for planning effective cancer control programs, nor easy implementation of such programs are available, due to limited financial resources.</P>

Quantification of cation-π interactions in like-charged polyelectrolytes inspired by mussels

Sohee Park,Young Mee Jung,Dong Soo Hwang 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

Computer-aided design and growth of single-walled carbon nanotubes on 4in. wafers for electronic device applications

Park, Serin,Park, Sohee,So, Hye-Mi,Jeon, Eun-Kyoung,Park, Dong-Won,Kim, Ju-Jin,Kim, Beom Soo,Kong, Ki-jeong,Chang, Hyunju,Lee, Jeong-O. Elsevier 2010 Carbon Vol.48 No.8

<P><B>Abstract</B></P><P>We have employed computer-aided furnace design and process simulation to optimize the conditions under which single-walled carbon nanotubes (SWCNTs) may be grown in high yields on 4in. wafers for electronic device applications. Hydrokinetic simulations were performed to obtain optimized furnace structures and process conditions in terms of gas flow, temperature, and gas speed. Shower head structures and a flow isolation barrier were installed in an experimental 6in. furnace, as suggested by the hydrokinetic simulations. To ensure clean surfaces and uniform catalyst islands, catalyst patterns were lifted off using Au films or polydimethylsiloxane. Photolithography was used to fabricate field-effect transistors with SWCNTs grown on 4in. wafer substrates. The total yield of the nanotube devices increased from 30.5% to 96.4% after optimization.</P>

Case series of nerve injuries during laparoscopic or robotic gynecologic surgery

( Sohee Park ),( Hayeon Kim ),( Jae Hong Sang ),( Soo-ho Chung ),( Jeong In Choi ) 대한산부인과학회 2022 대한산부인과학회 학술대회 Vol.108 No.-

Nerve injuries during gynecologic endoscopy are rare but distressing complication. Upper and lower limb peripheral nerves are the most common nerves injured during laparoscopic or robotic gynecologic surgery. The probable cause of nerve injury is the posture the patient maintained during surgery. Restraining arms during general anesthesia with an unintentional change in the angle of the arm in the Trendelenburg position, may lead to hyperextension of the arm, resulting in pressure on and stretching of the brachial plexus nerve and neurologic damage. High lithotomy with extreme flexion at the hip and steep Trendelenburg positions can contribute to perioperative lower limb peripheral nerve injuries. We present several cases of patients who underwent laparoscopic or robotic gynecologic surgery and had nerve injuries

Fabrication of arrangement-controlled and vertically grown ZnO nanorods by metal nanotransfer printing

Sohee Cheon,Won Woo Lee,Won Il Park,Joo-Yun Jung,Jun-hyuk Choi,Dae-geun Choi,Sohee Jeon,Jun-ho Jeong,Jihye Lee 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.81 No.-

Vertically aligned ZnO nanorods have been widely investigated for use in piezoelectric generators,photovoltaic devices, nanotemplates, photoelectrochemical applications, etc. In addition to verticalalignment, intentional arrangement of ZnO nanorods according to a careful design can enhance thedevice performance. In this work, we used metal nanotransfer printing to fabricate arrangement-controlled and vertically grown ZnO nanorods on both hard andflexible substrates. Highly verticalgrowth and periodical arrangement of the ZnO nanorods were confirmed by microscope images. Theircrystallinity and photoluminescence characteristics were also investigated. Transmission spectra of thesubstrates show the enhancement of optical transmission after the nanorod growth. We believe that thisfabrication technique lends itself to simple fabrication of arrangement-controlled and vertically grownone-dimensional nanostructures on both hard andflexible substrates for application in solar cells, watersplitting, metamaterials, etc.

Attribution to Heterogeneous Risk Factors for Breast Cancer Subtypes Based on Hormone Receptor and Human Epidermal Growth Factor 2 Receptor Expression in Korea

Park, Boyoung,Choi, Ji-Yeob,Sung, Ho Kyung,Ahn, Choonghyun,Hwang, Yunji,Jang, Jieun,Lee, Juyeon,Kim, Heewon,Shin, Hai-Rim,Park, Sohee,Han, Wonshik,Noh, Dong-Young,Yoo, Keun-Young,Kang, Daehee,Park, Su Wolters Kluwer Health 2016 Medicine Vol.95 No.14

<▼1><P>Supplemental Digital Content is available in the text</P></▼1><▼2><P><B>Abstract</B></P><P>We conducted a heterogeneous risk assessment of breast cancer based on the hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) calculating the risks and population-based attributable fractions (PAFs) for modifiable and nonmodifiable factors.</P><P>Using matched case–control study design from the Seoul Breast Cancer Study and the national prevalence of exposure, the risks and PAFs for modifiable and nonmodifiable factors were estimated for total breast cancers and subtypes.</P><P>The attribution to modifiable factors was different for each subtype (luminal A, PAF = 61.4% [95% confidence interval, CI = 54.3%–69.8%]; luminal B, 21.4% [95% CI = 18.6–24.9%]; HER2-overexpression, 59.4% [95% CI = 47.8%–74.3%], and triple negative tumors [TNs], 27.1% [95% CI = 22.9%–32.4%)], and the attribution to the modifiable factors for the luminal A and HER2-overexpression subtypes was higher than that of the luminal B and TN subtypes (<I>P</I> heterogeneity ≤ 0.001). The contribution of modifiable reproductive factors to luminal A type in premenopausal women was higher than that of the other subtypes (18.2% for luminal A; 3.1%, 8.1%, and −3.1% for luminal B, HER2-overexpression, and TN subtypes, respectively; <I>P</I> heterogeneity ≤ 0.001). Physical activity had the highest impact preventing 32.6% of luminal A, 14.5% of luminal B, 38.0% of HER2-overexpression, and 26.9% of TN subtypes (<I>P</I> heterogeneity = 0.014). Total reproductive factors were also heterogeneously attributed to each breast cancer subtype (luminal A, 65.4%; luminal B, 24.1%; HER2-overexpression, 57.9%, and TN subtypes, −3.1%; <I>P</I> heterogeneity ≤ 0.001).</P><P>Each pathological subtype of breast cancer by HRs and HER2 status may be associated with heterogeneous risk factors and their attributable risk, suggesting a different etiology. The luminal B and TN subtypes seemed to be less preventable despite intervention for alleged risk factors, even though physical activity had a high preventable potential against breast cancer.</P></▼2>

Photo-induced hybrid nanopatterning of titanium dioxide <i>via</i> direct imprint lithography

Park, Hyeong-Ho,Choi, Dae-Geun,Zhang, Xin,Jeon, Sohee,Park, Seong-Je,Lee, Soon-Won,Kim, Sarah,Kim, Ki-don,Choi, Jun-Hyuk,Lee, Jihye,Yun, Dae Keun,Lee, Ki Joong,Park, Hyung-Ho,Hill, Ross Henry,Jeong, J Royal Society of Chemistry 2010 Journal of materials chemistry Vol.20 No.10

<P>A novel ultraviolet (UV)-assisted imprinting procedure that employs photosensitive titanium(<SMALL>IV</SMALL>) di-n-butoxide bis(2-ethylhexanoate) is presented for the fabrication of well-ordered titanium dioxide (TiO<SUB>2</SUB>) nanostructures at room temperature. The main novelty of this technique is the use of the photosensitive titanium organic compound, rather than a commonly used UV-curable resin, for direct UV-assisted nanoimprint lithography. Fourier transform infrared and X-ray photoelectron spectroscopy studies suggest that exposure to UV light resulted in the gradual removal of organic groups from films prepared from titanium(<SMALL>IV</SMALL>) di-n-butoxide bis(2-ethylhexanoate) photochemically and successively converted the films to TiO<SUB>2</SUB> at room temperature. This approach allows direct fabrication of TiO<SUB>2</SUB> nanopatterns with lines down to 35 nm in width, hole arrays of 265 nm in diameter, and three-dimensional TiO<SUB>2</SUB> hybrid micro/nano-patterns without observable defects for use in applications where ordered surface nanostructures are required, such as photovoltaics, photonics, and optical waveguides.</P> <P>Graphic Abstract</P><P>A novel UV-assisted imprinting procedure that employs photosensitive Ti(<SMALL>IV</SMALL>) di-n-butoxide bis(2-ethylhexanoate) is presented for the fabrication of well-ordered TiO<SUB>2</SUB> and 3-D TiO<SUB>2</SUB> hybrid micro/nano-patterns at room temperature. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b921343k'> </P>

In vitro wound healing: Inhibition activity of insect-derived mAb CO17-1A in human colorectal cancer cell migration

Park Se Ra,Ko Kisung,Lim Sohee,Cha So Yeon,정현주,Park Soon Ju,Myung Soon‐Chul,Kim Mi Kyung 한국곤충학회 2020 Entomological Research Vol.50 No.4

The monoclonal antibody (mAb) CO17-1A specifically binds to the tumor associated cell surface glycoprotein GA733 in colorectal cancer cells. Thus, mAb CO17-1A has the potential to act as an immune therapeutic protein against colorectal cancer. Recently, it was shown that the baculovirus insect cell expression system produces anti-colorectal cancer mAb CO17-1A. In this study, the colorectal cancer antibody mAb CO17-1A fused to the endoplasmic reticulum (ER) retention signal sequence (KDEL), and the (mAb CO17-1AK) was expressed in Spodoptera frugiperda Sf9 insect cells. The yield, cell cytotoxicity, and in vitro anti-tumor activity of mAb CO17-1AK were verified. Western blotting was performed to confirm that both heavy and light chains of mAb CO17-1A were expressed in Sf9 insect cells. The insect-derived mAb (mAbI ) CO17-1A was purified using a protein G affinity column. An in vitro wound healing assay was conducted to determine the inhibition activity of mAb CO17-1A during tumor cell migration, showing that mAbI CO17-1AK was effective as mammalian-derived mAb CO17-1A (mAbM CO17-1A). These results suggest that the insect cell expression system can produce and properly assemble mAbs that inhibit tumor cell migration.