Skin Penetration-Inducing Gelatin Methacryloyl Nanogels for Transdermal Macromolecule Delivery

Kim, Jeehye,Gauvin, Robert,Yoon, Hee Jeong,Kim, Jin-Hoi,Kwon, Sang-Mo,Park, Hyun Jin,Baek, Sang Hong,Cha, Jae Min,Bae, Hojae The Polymer Society of Korea 2016 Macromolecular Research Vol.24 No.12

In this study, the suitability of gelatin methacryloyl (GelMA) nanogels for transdermal delivery of macromolecules was demonstrated. The synthesis of GelMA nanogels (GNs) and fluorescein isothiocyanate labelled bovine serum albumin (FITC-BSA) loaded GelMA nanogels (FGNs) were implemented when confined in water-in-oil nanoemulsion droplets via the photopolymerization of the methacryloyl substituents to create crosslinked nanogels. Both GNs and FGNs existed as fine particles in aqueous condition (pH 7.4) for 7 days. No distinct aggregation of nanogel particles were observed. In the MTT assay, high percentage of cell viability indicated that GNs did not exhibit any growth inhibitory effect or significant cytotoxicity. The skin penetration study results showed that FGNs permeated across the epidermis and into the dermis of a porcine model when compared to the FITC-BSA dissolved in PBS. Possible penetration routes of FITC-BSA through the stratum corneum (SC) were illustrated by visualizing the SC structure with fluorescent signals of FITC-BSA. The penetration mechanism of FGNs across the SC layer was successfully demonstrated by explaining three penetration routes (intercellular, follicular, and transcellular route). The results suggest that GNs have a potential as a transdermal delivery carrier for hydrophilic macromolecules.

Cellular Uptake Mechanism of TCTP-PTD in Human Lung Carcinoma Cells

Kim, Hyo Young,Kim, Sabin,Pyun, Hae Jun,Maeng, Jeehye,Lee, Kyunglim American Chemical Society 2015 MOLECULAR PHARMACEUTICS Vol.12 No.1

Trends in emergency department visits for emergency care–sensitive conditions before and during the COVID-19 pandemic: a nationwide study in Korea, 2019–2021

Kim Seonji,Sung Ho Kyung,Lee Jeehye,Ko Eunsil,Kim Seong Jung 대한응급의학회 2024 Clinical and Experimental Emergency Medicine Vol.11 No.1

Objective: Emergency care systems worldwide have been significantly affected by the COVID-19 pandemic. This study investigated the trend of emergency department (ED) visits for emergency care–sensitive conditions (ECSCs) in Korea before and during the pandemic.Methods: We performed a longitudinal study using the national ED database in Korea from January 2019 to December 2021. We calculated the number and incidence rate (IR) of visits for ECSCs per 100,000 ED visits, and the IR ratio (IRR) of 2021 relative to the value in 2019. The selected ECSCs were intracranial injury, ischemic heart disease (IHD), stroke, and cardiac arrest.Results: The number of ED visits for all causes decreased by about 23% during the pandemic. The number of ED visits for intracranial injuries decreased from 166,695 in 2019 to 133,226 in 2020 and then increased to 145,165 in 2021. The number of ED visits for IHD and stroke decreased in 2020 but increased to 2019 levels in 2021. In contrast, the number of ED visits for cardiac arrest increased from 23,903 in 2019 to 24,344 in 2020 and to 27,027 in 2021. The IR and IRR of these four ECSCs increased from 2019 to 2021, suggesting increasing relative proportions of ECSCs in total ED visits. Conclusion: During the COVID-19 pandemic, the number of cardiac arrests seen in the EDs increased, but that of other ECSCs decreased. The decrease in ED visits for ECSCs was not as pronounced as the decrease in ED visits for all causes during the pandemic. Further studies are needed to determine clinical outcomes in patients with ECSC during the pandemic.

Structure–Property Relationships of Semiconducting Polymers for Flexible and Durable Polymer Field-Effect Transistors

Kim, Min Je,Jung, A-Ra,Lee, Myeongjae,Kim, Dongjin,Ro, Suhee,Jin, Seon-Mi,Nguyen, Hieu Dinh,Yang, Jeehye,Lee, Kyung-Koo,Lee, Eunji,Kang, Moon Sung,Kim, Hyunjung,Choi, Jong-Ho,Kim, BongSoo,Cho, Jeong H American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.46

<P>We report high-performance top-gate bottom-contact flexible polymer field-effect transistors (FETs) fabricated by flow-coating diketopyrrolopyrrole (DPP)-based and naphthalene diimide (NDI)-based polymers (P(DPP2DT-T2), P(DPP2DT-TT), P(DPP2DT-DTT), P(NDI2OD-T2), P(NDI2OD-F2T2), and P(NDI2OD-Se2)) as semiconducting channel materials. All of the polymers displayed good FET characteristics with on/off current ratios exceeding 10(7). The highest hole mobility of 1.51 cm(2) V-1 s(-1) and the highest electron mobility of 0.85 cm(2) V-1 s(-1) were obtained from the P(DPP2DT-T2) and P(NDI2OD-Se2) polymer FETs, respectively. The impacts of the polymer structures on the FET performance are well-explained by the interplay between the crystallinity, the tendency of the polymer backbone to adopt an edge-on orientation, and the interconnectivity of polymer fibrils in the film state. Additionally, we demonstrated that all of the flexible polymer-based FETs were highly resistant to tensile stress, with negligible changes in their carrier mobilities and on/off ratios after a bending test. Conclusively, these high-performance, flexible, and durable FETs demonstrate the potential of semiconducting conjugated polymers for use in flexible electronic applications.</P>

Survey of Shape Resonances for Photoionizing Transitions

KIM, SOOKHYUN OH, SUNG DAHM CHOI, JEEHYE BAE, JEAN KIM, YOUNG SOON 숙명여자대학교 자연과학연구소 1989 자연과학논문집 Vol.- No.1

The existence of shape resonances for photoionizing transitions in ground state neutral atoms have been investigated using a one electron model with a Herman-Skillman central potential. The effective potential should have an attractive well near the nucleus and a repulsive barrier at the atomic region, and phase shifts of the final continuum wave functions should rapidly increase by π. Only Xe, Cs, Rn and Fr atoms have a shape resonance in transitions to the f channel.

Comparison of District-level Smoking Prevalence and Their Income Gaps from Two National Databases: the National Health Screening Database and the Community Health Survey in Korea, 2009–2014

Kim, Ikhan,Bahk, Jinwook,Kim, Yeon-Yong,Lee, Jeehye,Kang, Hee-Yeon,Lee, Juyeon,Yun, Sung-Cheol,Park, Jong Heon,Shin, Soon-Ae,Khang, Young-Ho KOREAN ACADEMY OF MEDICAL SCIENCE 2018 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.33 No.6

<P><B>Background</B></P><P>We compared age-standardized prevalence of cigarette smoking and their income gaps at the district-level in Korea using the National Health Screening Database (NHSD) and the Community Health Survey (CHS).</P><P><B>Methods</B></P><P>Between 2009 and 2014, 39,049,485 subjects participating in the NHSD and 989,292 participants in the CHS were analyzed. The age-standardized prevalence of smoking and their interquintile income differences were calculated for 245 districts of Korea. We examined between-period correlations for the age-standardized smoking prevalence at the district-level and investigated the district-level differences in smoking prevalence and income gaps between the two databases.</P><P><B>Results</B></P><P>The between-period correlation coefficients of smoking prevalence for both genders were 0.92–0.97 in NHSD and 0.58–0.69 in CHS, respectively. When using NHSD, we found significant income gaps in all districts for men and 244 districts for women. However, when CHS was analyzed, only 167 and 173 districts for men and women, respectively, showed significant income gaps. While correlation coefficients of district-level smoking prevalence from two databases were 0.87 for men and 0.85 for women, a relatively weak correlation between income gaps from the two databases was found.</P><P><B>Conclusion</B></P><P>Based on two databases, income gaps in smoking prevalence were evident for nearly all districts of Korea. Because of the large sample size for each district, NHSD may provide stable district-level smoking prevalence and its income gap and thus should be considered as a valuable data source for monitoring district-level smoking prevalence and its socioeconomic inequality.</P>

Low-Band-Gap Polymer-Based Ambipolar Transistors and Inverters Fabricated Using a Flow-Coating Method

Kim, Min Je,Park, Jae Hoon,Kang, Boseok,Kim, Dongjin,Jung, A-Ra,Yang, Jeehye,Kang, Moon Sung,Lee, Dong Yun,Cho, Kilwon,Kim, Hyunjung,Kim, BongSoo,Cho, Jeong Ho American Chemical Society 2016 The Journal of Physical Chemistry Part C Vol.120 No.26

<P>The performances of organic thin film transistors (OTFTs) produced by polymer solution casting are tightly correlated with the morphology and chain-ordering of semiconducting polymer layers, which depends on the processing conditions applied. The slow evaporation of a high boiling point (bp) solvent permits sufficient time for the assembly of polymer chains during the process, resulting in improving the film crystallinity and inducing favorable polymer chain orientations for charge transport. The use of high bp solvents, however, often results in dewetting of thin films formed on hydrophobic surfaces, such as the commonly used octadecyltrichlorosilane (ODTS)-treated SiO2 gate dielectric. Dewetting hampers the formation of uniform and highly crystalline semiconducting active channel layers. In this manuscript, we demonstrated the formation of highly crystalline dithienothienyl diketopyrrolopyrrole (TT-DPP)-based polymer films using a flow-coating method to enable the fabrication of ambipolar transistors and inverters. Importantly, unlike conventional spin-coating methods, the flow-coating method allowed us to use high bp solvents, even on a hydrophobic surface, and minimized the polymer solution waste. The crystalline orientations of the TT-DPP-based polymers were tuned depending on the solvent used (four different bp solvents were tested) and the employment of a thermal annealing step. The use of high bp solvents and thermal annealing of the polymer films significantly enhanced the crystalline microstructures in the flow-coated films, resulting in considerable carrier mobility increase in the OTFTs compared to the spin-coated films. Our simple, inexpensive, and scalable flow-coating method, for the first time employed in printing semiconducting polymers, presents a significant step toward optimizing the electrical performances of organic ambipolar transistors through organic semiconducting layer film crystallinity engineering.</P>

Predicting stage ypT0–1N0 for nonradical management in patients with middle or low rectal cancer who undergo neoadjuvant chemoradiotherapy: a retrospective cohort study

Jeehye Lee,In Jun Yang,Jung Wook Suh,Hong-min Ahn,Heung-Kwon Oh,Duck-Woo Kim,Young-Hoon Kim,Kyoung Ho Lee,Sung-Bum Kang 대한외과학회 2022 Annals of Surgical Treatment and Research(ASRT) Vol.103 No.1

Purpose: It is important to discover predictive factors that can identify rectal cancer patients who will respond well to neoadjuvant concurrent chemoradiotherapy (CCRT) to develop management strategies, preserve sphincter and avoid over- treatment. This study explored clinical factors that would predict the adequacy of nonradical management after CCRT in patients with middle or low rectal cancer. Methods: We retrospectively evaluated 447 patients with middle or low rectal cancer who were treated with curative surgery after neoadjuvant CCRT between January 2010 and December 2019. The good response group comprised patients with stages ypT0–1N0 on resection after CCRT; the remaining patients were included in the poor response group. Results: Of 447 patients (mean age, 60.37 ± 11.85 years), 108 (24.2%) had ypT0–1N0 (71.3% with ypT0N0, 4.6% with ypTisN0, and 24.1% with ypT1N0). Overall, 19 patients with cT1–2 (50.0% . 21.8% with cT3–4, P < 0.001), 22 with well-differentiated tumors (51.2% . 21.3% with moderately/poorly differentiated tumors, P < 0.001), 16 with fungating tumors (47.1% . 22.3% with other types, P = 0.001), and 66 with anterior/posterior circumference direction (28.9% . 19.2% with lateral/ encircling direction, P = 0.016) had stage ypT0–1N0. On multivariable analysis, cT1–2 (P = 0.021) and well-differentiated tumor (P = 0.001) were independent predictors of ypT0–1N0. Fungating tumors were not significantly associated with ypT0– 1N0 (P = 0.054). Conclusion: Stage cT1–2 and well differentiation are predictors of ypT0–1N0, while fungating tumors could be considered clinically meaningful, possibly identifying candidates for nonradical treatment post-CCRT.

Prevalence of Overweight and Income Gaps in 245 Districts of Korea: Comparison Using the National Health Screening Database and the Community Health Survey, 2009–2014

Kim, Ikhan,Bahk, Jinwook,Kim, Yeon-Yong,Lee, Jeehye,Kang, Hee-Yeon,Lee, Juyeon,Yun, Sung-Cheol,Park, Jong Heon,Shin, Soon-Ae,Khang, Young-Ho The Korean Academy of Medical Sciences 2018 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.33 No.1

<P><B>Background</B></P><P>We compared age-standardized overweight prevalence and their income gaps at the level of district in Korea using the National Health Screening Database (NHSD) and the Community Health Survey (CHS).</P><P><B>Methods</B></P><P>We analyzed 39,093,653 subjects in the NHSD and 926,580 individuals in the CHS between 2009 and 2014. For the comparison of body mass index (BMI) distributions, data from 26,100 subjects in the Korea National Health and Nutrition Examination Survey (KNHANES) were also analyzed. We calculated the age-standardized overweight prevalence and its interquintile income gap at the district level. We examined the magnitudes of the between-period correlation for age-standardized overweight prevalence. The differences in overweight prevalence and its income gap between the NHSD and the CHS were also investigated.</P><P><B>Results</B></P><P>The age-adjusted mean BMI from the CHS was lower than those from the NHSD and the KNHANES. The magnitudes of the between-period correlation for overweight prevalence were greater in the NHSD compared to the CHS. We found that the district-level overweight prevalence in the NHSD were higher in all districts of Korea than in the CHS. The correlation coefficients for income gaps in overweight prevalence between the two databases were relatively low. In addition, when using the NHSD, the district-level income inequalities in overweight were clearer especially among women than the inequalities using the CHS.</P><P><B>Conclusion</B></P><P>The relatively large sample size for each district and measured anthropometric data in the NHSD are more likely to contribute to valid and reliable measurement of overweight inequality at the district level in Korea.</P>

Highly loaded PbS/Mn-doped CdS quantum dots for dual application in solar-to-electrical and solar-to-chemical energy conversion

Kim, Jae-Yup,Jang, Youn Jeong,Park, Jongwoo,Kim, Jeehye,Kang, Jin Soo,Chung, Dong Young,Sung, Yung-Eun,Lee, Changhee,Lee, Jae Sung,Ko, Min Jae Elsevier 2018 Applied Catalysis B Vol.227 No.-

<P><B>Abstract</B></P> <P>Among the various renewable sources of energy, solar energy conversion systems have been regarded as a promising way to satisfy the growing energy demand. For superior solar energy conversion performance, it is important to utilize efficient photosensitizers that have excellent light-harvesting capability. In this regard, quantum dots (QDs) are promising photosensitizer candidates owing to their high absorption coefficient, band gap tunability, and potential multiple exciton generation. Here, we report an effective and straightforward approach to improve the loadings of nanocomposite PbS/CdS QDs in a mesoporous electrode, for highly efficient solar energy conversion. By controlling the surface charge of TiO<SUB>2</SUB> during the successive ionic layer adsorption and reaction process, both the PbS and CdS QD loadings are distinctly increased, leading to a highly enhanced light-harvesting capability of the photoelectrodes. This enhancement is effectively applied not only for solar-to-electrical but also for solar-to-chemical energy conversion, resulting in a ∼33% increased conversion efficiency of the QD solar cells and an unprecedented photocurrent of 22.1 mA/cm<SUP>2</SUP> (at 0.6 V vs<I>.</I> RHE) for hydrogen production from photoelectrochemical water splitting. These results provide significant insight into the application of QD photosensitizers in solar energy conversion.</P> <P><B>Highlights</B></P> <P> <UL> <LI> PbS/Mn-doped CdS QDs were loaded on a mesoporous electrode. </LI> <LI> The QD loadings were increased by controlling the electrode surface charge. </LI> <LI> Due to the enhanced QD loadings, the efficiency of QD solar cells was increased by ∼33%. </LI> <LI> When applied in PEC water splitting, a remarkable photocurrent density of 22.1 mA/cm<SUP>2</SUP> was obtained. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>