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The usefulness of the status of extranodal tumor extension as a factor that can predict the recurrence of stage III colorectal cancer
No full textBackground: Extranodal tumor extension (ENTE) is considered a poor prognostic factor in colorectal cancer (CRC). This study aimed to investigate the risk factors for recurrence according to ENTE status in stage III CRC. Methods: We retrospectively evaluated 169 consecutive stage III CRC patients. All patients underwent a curative resection between 2005 and 2010. The presence or absence of ENTE was assessed in the resected lymph nodes. Results: ENTE was observed in 65 (38.5%). Recurrence occurred in 38 patients (22.5%) and was more frequent (p =.041) in the ENTE (+) group. Disease-free survival (p =.016) was significantly shorter in the ENTE (+) group than in the ENTE (−) group. In a univariable analysis, recurrence was associated with vascular invasion (p =.006), perforation (p =.024) in the ENTE (−) group and perforation (p =.048) in the ENTE (+) group. In a Cox’s regression test, vascular invasion (p =.014) and the higher ratio of metastatic lymph nodes/total removed lymph nodes (MLN/TLN) (0.009) in the ENTE (−) group and perforation (p =.025) in the ENTE (+) group were independent risk factors of recurrence. Conclusions: Vascular invasion and the higher ratio of MLN/TLN in ENTE (−) patients and perforation in ENTE (+) patients were independent risk factors of recurrence. © 2018, © 2019 The Royal Belgian Society for Surgery.This work was supported by the research fund of Hanyang University [HY-2014]
Thermochromic Polydiacetylene Nanotube from Amphiphilic Macrocyclic Diacetylene in Aqueous Solution
No full textCreation of tubular structures through the self-assembly of macrocyclic molecules has gained great attention in the chemical, biochemical, and material sciences. Through a designed introduction of two octaethylene oxide and two diacetylene moieties, we prepared a macrocycle MCDA BisOEG, which is water-soluble and photopolymerizable and displays a lower critical solution temperature (LCST) behavior. The hydrodynamic diameter of MCDA BisOEG, measured by dynamic light scattering method, was ca. 6.5 rim at 25 degrees C and increased sharply to ca. 2 mu m at temperatures above 34 degrees C (LCST). Below the LCST, the macrocycle in aqueous solution formed tubular structures, which upon UV irradiation generated blue conjugated polydiacetylene (PDA) nanotubes. The PDA nanotubes undergo a blue-to-red color change when heated above the LCST. No polymerization occurs above the LCST owing to the disordered aggregation of the diacetylene monomer. This is the first example of the preparation of a macrocycle-based, thermoresponsive, conjugated polymer nanotube in aqueous solution.This study was supported financially by the Samsung Research Funding Center of the Samsung Electronics under the project number SRFC-MA1501-06 and by the National Research Foundation of Korea (NRF-2017R1A2A1A05000752)
Molecular diagnosis of hereditary spherocytosis by multi-gene target sequencing in Korea: matching with osmotic fragility test and presence of spherocyte
No full textBACKGROUND:
Current diagnostic tests for hereditary spherocytosis (HS) focus on the detection of hemolysis or indirectly assessing defects of membrane protein, whereas direct methods to detect protein defects are complicated and difficult to implement. In the present study, we investigated the patterns of genetic variation associated with HS among patients clinically diagnosed with HS.
METHODS:
Multi-gene targeted sequencing of 43 genes (17 RBC membrane protein-encoding genes, 20 RBC enzyme-encoding genes, and six additional genes for the differential diagnosis) was performed using the Illumina HiSeq platform.
RESULTS:
Among 59 patients with HS, 50 (84.7%) had one or more significant variants in a RBC membrane protein-encoding genes. A total of 54 significant variants including 46 novel mutations were detected in six RBC membrane protein-encoding genes, with the highest number of variants found in SPTB (n = 28), and followed by ANK1 (n = 19), SLC4A1 (n = 3), SPTA1 (n = 2), EPB41 (n = 1), and EPB42 (n = 1). Concurrent mutations of genes encoding RBC enzymes (ALDOB, GAPDH, and GSR) were detected in three patients. UGT1A1 mutations were present in 24 patients (40.7%). Positive rate of osmotic fragility test was 86.8% among patients harboring HS-related gene mutations.
CONCLUSIONS:
This constitutes the first large-scaled genetic study of Korean patients with HS. We demonstrated that multi-gene target sequencing is sensitive and feasible that can be used as a powerful tool for diagnosing HS. Considering the discrepancies of clinical and molecular diagnoses of HS, our findings suggest that molecular genetic analysis is required for accurate diagnosis of HS.Support was provided by: the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (NRF-2017R1A2A1A17069780) http://www.nrf.re.kr/
Comparative efficacy of various anti-ulcer medications after gastric endoscopic submucosal dissection: a systematic review and network meta-analysis
No full textBackgroundThe comparative efficacy of various anti-ulcer medications after gastric endoscopic submucosal dissection (ESD) has not been fully evaluated. Recently, vonoprazan, a novel potassium-competitive acid blocker, has also been used in ulcer treatment after ESD.MethodsWe searched for all relevant randomized controlled trials examining the efficacy of anti-ulcer medications after gastric ESD, published through October 2017. Healing of iatrogenic ulcers was investigated at 4-8weeks after ESD. A network meta-analysis was performed to calculate the network estimates.ResultsTwenty-one studies with 2005 patients were included. Concerning the comparative efficacy for ulcer healing at 4weeks after ESD, no network inconsistency was identified (Cochran's Q-test, df=10, P=0.13; I-2=34%). A combination therapy of proton-pump inhibitor (PPI) and muco-protective agent was superior to PPI alone [risk ratio (RR) (95% confidence interval, CI) 1.69 (1.20-2.39)]. The combination therapy of PPI and muco-protective agents tended to be superior to vonoprazan [RR (95% CI) 1.98 (0.99-3.94)]. There was no difference of ulcer healing effect between PPI and vonoprazan [RR (95% CI) PPI vs. vonoprazan, 1.17 (0.64-2.12)]. Concerning the ulcer healing rate at 8weeks after ESD, however, vonoprazan was superior to PPI [RR (95% CI) 1.27 (1.03-1.56)]. Additionally, vonoprazan tended to be superior to the combination therapy of PPI and muco-protective agent [RR (95% CI) 1.20 (0.96-1.51)].ConclusionsA combination therapy of PPI and muco-protective agent was superior to PPI alone for ulcer healing at 4weeks after ESD. In the ulcer healing effect at 8weeks after ESD, vonoprazan was superior to PPI.This work was supported by the research fund of Hanyang University (HY-2017)
Design of Active Front Steering Control System Considering Roll Dynamic Characteristics of Vehicle
No full textIn this paper, we propose the advanced Active Front Steering Control algorithm for improving cornering stability. When the vehicle is turning at high speed, roll motion occurs at the sprung mass. It induces steering movements that delay or interfere with the steering input. So, we designed the controller to take roll motions into account to improve cornering stability. From the numerical simulation study using MATLAB/CarSim, we observed that the performance of proposed control algorithm improves vehicle cornering performance.본 연구는 2019 년도 산업통상자원부 및 산업기술평가관리 3. 롤 역학을 고려한 AFS 제어시스템 설계원(KEIT) 연구비 지원(20000293, 환경센서와 차량내부센서 융합기반 노면상태 검출 기술 개발) 과 산업통상자원부 및 중소벤처기업부의 연구비 지원(S2367759, 이종카메라 스테
레오 매칭 방법 및 자동주차 시스템 개발) 에 의하여 연구되었음
Combined effects of sulfamethazine and sulfamethoxazole on a freshwater microalga, Scenedesmus obliquus: toxicity, biodegradation, and metabolic fate
No full textThis study investigated the environmental effects of two common emerging contaminants, sulfamethazine (SMZ) and sulfamethoxazole (SMX), and their mixture using a green microalga, Scenedesmus obliquus. The calculated EC50 values of SMZ, SMX, and their mixture (11:1 wt/wt) after 96 h were 1.23, 0.12, and 0.89 mg L-1, respectively. The toxicity of the mixture could be better predicted using a concentration addition model than an independent action model. The risk quotients of SMZ, SMX, and their mixture were > 1 during the experiment, indicating their high potential risks on aquatic microorganisms. Despite their toxicity, S. obliquus exhibited 17.3% and 29.3% removal of 0.1 mg L-1 and 0.2 mg L-1 after 11 days of cultivation. The changes of SMZ and SMX removal were observed when combined, which showed a significantly improved removal of SMZ (up to 3.4 folds) with addition of SMX (0.2 mg L-1). The metabolic pathways of SMZ and SMX were proposed according to mass spectroscopic analysis, which showed six metabolites of SMX and seven intermediates of SMZ, formed as a result of ring cleavage, hydroxylation, methylation, nitrosation, and deamination.This study was supported by National Research Foundation of Korea (NRF) grants funded by the Ministry of Education, Science, and Technology (MEST) of the South Korean government (No. 2017R1A2B2004143), and the Doosan Yonkang Foundation
P‐170: Circularly Polarized Electroluminescence in a Low Molecular Weight Mesogenic Compound
No full textWe studied the properties of circularly polarized OLEDs based on twisted low molecular weight emitting compound with mesogenic phase. Through quenching the spin-coated compound after heating at its mesogenic phase, twisted configuration and circularly polarized emission are obtained.This work supported by LG Displa
Glia-Like Cells from Late-Passage Human MSCs Protect Against Ischemic Stroke Through IGFBP-4.
No full textStem cell therapy is considered to be a promising future treatment for intractable neurological diseases, although all the clinical trials using stem cells have not yet shown any good results. Early passage mesenchymal stem cells (MSCs) have been used in most clinical trials because of the issues on safety and efficacy. However, it is not easy to get plenty of cells enough for the treatment and it costs too much. Lots of late passage MSCs can be obtained at lower cost but their efficacy would be a big hurdle for clinical trials. If late passage MSCs with better efficacy could be used in clinical trials, it could be a new and revolutionary solution to reduce cost and enhance easier clinical trials. In the present study, it was investigated whether late passage MSCs could be induced into glia-like cells (ghMSCs); ghMSCs had better efficacy and they protected neurons and the brain from ischemia, and insulin-like growth factor binding protein-4 (IGFBP-4) played a critical role in beneficial effect of ghMSCs. ghMSCs were induced from MSCs and treated in in vitro and in vivo models of ischemia. They effectively protected neurons from ischemia and restored the brain damaged by cerebral infarction. These beneficial effects were significantly blocked by IGFBP-4 antibody. The current study demontsrated that late passage hMSCs can be efficiently induced into ghMSCs with better neuroprotective effect on ischemic stroke. Moreover, the results indicate that IGFBP-4 released from ghMSCs may serve as one of the key neuronal survival factors secreted from ghMSCs. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.This research was supported by a grant from the Korea Health Technology R&D Project through the Korea Health
Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number HI17C2160)
Discrimination of phthalate species using a simple phage-based colorimetric sensor in conjunction with hierarchical support vector machine
No full textHere, the analytical potential of an M13 bacteriophage-based color sensor for discrimination of 4 phthalates with similar molecular structures (bis-(2-ethylhexyl)-phthalate (BEHP), dibutyl phthalate (DBP), diethyl phthalate (DEP), and benzyl-butyl-phthalate (BBP)) was investigated. The pattern and magnitude of the RGB color changes were different depending on the functional groups present in the phthalate structures. For example, BEHP possessing a long alkyl chain resulted in a minute color change, while the variation of color was substantially large when BBP containing an additional benzene ring was measured. Since a tryptophan-histidine-tryptophan residue possessing indole and imidazole was present on the self-assembled phages, the pi-pi interaction of benzene in BBP with the sensor surface produced a considerably greater color change. To evaluate the multi-modally varying color signals due to diverse interactions of the phthalates with the sensor and to discriminate them, support vector machine (SVM), which can construct a boundary hyperplane among complexly scattered sample groups, was used. In addition, hierarchical SVM (H-SVM) was adopted to deal with multi-class discrimination. The use of H-SVM improved the discrimination accuracy up to 90.1%, compared to 87.1% using SVM. The demonstrated color sensor is versatile and can be potentially adopted as an on-site screening tool. Strategies to improve the accuracy further for real applications are also discussed.This work was supported by the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry (IPET) through the Advanced Production Technology Development Program of the Ministry of Agriculture, Food and Rural Affairs (MAFRA) (31608004) and the Bio & Medical Technology Development Program of the National Research Foundation (NRF) funded by the Ministry of Science & ICT (No. 2017M3A9G8084539)
A theoretical insight into the role of counter anions and their interactions in nitropentaamminecobalt(III) toward linkage isomerism-induced photochemical motion
No full textDensity functional theory (B3LYP, B3LYP-D3, wB97XD, M062X, and M06L) and ab initio methods (MP2 and CCSD(T)) in conjunction with 6-31+G(d,p) and LanL2DZ were employed to investigate the interaction energies between [Co(NH3)(5)NO2](2+) linkage isomers and chloride and nitrate in both gas phase and solid state. The nature of the chemical bonding has been analyzed by means of the atoms in molecules, electron density shift, natural bond orbitals, symmetry adapted perturbation theory, and energy decomposition analysis. The electronic structures of the two lowest laying singlet states (S-o and S-1) of [Co(NH3)(5)NO2](NO3)Cl isomers were also investigated using CASSCF(6,6) with LanL2DZ and 6-31G(d) basis sets. Our results show that [Co(NH3)(5)NO2](2+) linkage isomers interact more strongly with chloride than nitrate. The structures of [Co(NH3)(5)NO2](NO3)Cl linkage isomers and their relative stabilities were examined in gas phase and in solid state and confirmed the nitro-complex as the most stable following by a viable intermediate endo-complex. Study of the nitro-nitrito linkage isomerization in [Co(NH3)(5)NO2](NO3)Cl revealed that anions form strong electrostatic bonds with [Co(NH3)(5)NO2](2+) leading to decrease in an activation energy compared to the [Co(NH3)(5)ONO](2+) isomers. A concerted action of ionic interactions and hydrogen bonds are suspected of regulating the isomerization in solid state. Assessment of various DFT methods with respect to CCSD(T) suggests M062X suitable method for [Co(NH3)(5)NO2](NO3)Cl linkage-isomerization study. Potential energy surface calculations at the CASSCF/6-31G(d) level of theory shows that the conical intersection (S-1/S-o) might play an important role in the photoisomerization of [Co(NH3)(5)NO2](NO3)Cl.DBT BUILDER program, Grant/Award Number: BT/PR-9028/INF/22/193/2013.; Korea Research Fellowship program, Grant/Award Number: NRF2015H1D3A1062502; National Research Foundation of Korea; Ministry of Science, ICT and Future Plannin