https://pubs.kist.re.kr/handle/123456789/75372 2026-02-22T07:04:45Z https://pubs.kist.re.kr/handle/201004/121897 Title: Iodinated echogenic glycol chitosan nanoparticles for x-ray ct/us dual imaging of tumor Authors: Choi, D.; Jeon, S.; You, D.G.; Um, W.; Kim, J.-Y.; Yoon, H.Y.; Chang, H.; Kim, D.-E.; Park, J.H.; Kim, H.; Kim, K. Abstract: Development of biopolymer-based imaging agents which can access rapidly and provide detailed information about the diseases has received much attention as an alternative to conventional imaging agents. However, development of biopolymer-based nanomaterials for tumor imaging still remains challenging due to their low sensitivity and image resolution. To surmount of these limitations, multimodal imaging agents have been developed, and they were widely utilized for theranostic applications. Herein, iodine containing echogenic glycol chitosan nanoparticles are developed for x-ray computed tomography (CT) and ultrasound (US) imaging of tumor diagnosis. X-ray CT/US dual-modal imaging probe was prepared by following below two steps. First, iodine-contained diatrizoic acid (DTA) was chemically conjugated to the glycol chitosan (GC) for the CT imaging. DTA conjugated GC (GC-DTA NPs) formed stable nanoparticles with an average diameter of 315 nm. Second, perfluoropentane (PFP), a US imaging agent, was physically encapsulated into GC-DTA NPs by O/W emulsion method yielding GC-DTA-PFP nanoparticles (GC-DTA-PFP NPs). The GC-DTA-PFP NPs formed nanoparticles in physiological condition, and they presented the strong x-ray CT, and US signals in phantom test in vitro. Importantly, GC-DTA-PFP NPs were effectively accumulated on the tumor site by enhanced permeation and retention (EPR) effects. Moreover, GC-DTA-PFP NPs showed x-ray CT, and US signals in tumor tissues after intratumoral and intravenous injection, respectively. Therefore, GC-DTA-PFP NPs indicated that x-ray CT/US dual-modal imaging using iodinated echogenic nanoparticles could be provided more comprehensive and accurate diagnostic information to diagnosis of tumor. ？ Ivyspring International Publisher. 2018-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/121896 Title: Hybrid functional microfibers for textile electronics and biosensors Authors: Nanda, Sahoo B.; Choi, B.; Seo, J.; Lee, T. Abstract: Fibers are low-cost substrates that are abundantly used in our daily lives. This review highlights recent advances in the fabrication and application of multifunctional fibers to achieve fibers with unique functions for specific applications ranging from textile electronics to biomedical applications. By incorporating various nanomaterials such as carbon nanomaterials, metallic nanomaterials, and hydrogel-based biomaterials, the functions of fibers can be precisely engineered. This review also highlights the performance of the functional fibers and electronic materials incorporated with textiles and demonstrates their practical application in pressure/tensile sensors, chemical/biosensors, and drug delivery. Textile technologies in which fibers containing biological factors and cells are formed and assembled into constructions with biomimetic properties have attracted substantial attention in the field of tissue engineering. We also discuss the current limitations of functional textile-based devices and their prospects for use in various future applications. ？ 2018 Chinese Institute of Electronics. 2018-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/121895 Title: Synthesis and characterization of phosphorus- and sulfur-containing aromatic polyimides for high refractive index Authors: Kim, Hyeonil; Ku, Bon-Cheol; Goh, Munju; Yeo, Hyeonuk; Ko, Heung Cho; You, Nam-Ho Abstract: A new diamine, bis(4-((4-aminophenyl) thio) phenyl)(phenyl) phosphine oxide (BATPO), containing phosphine oxide and thioether bonds was prepared via the Grignard reaction to dichlor-ophenylphosphine oxide with 4-fluorophenylmagnesium bromide, followed by an aromatic substitution reaction with 4-aminothiophenol. The polyimides (PIs) were synthesized by the conventional two-step polycondensation from several aromatic dianhydrides, such as 4,4'-[p-thiobis(phenylenesulfanyl)]diphthalic anhydride (3SDEA), 4,4'-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), 4,4'-oxydiphthalic anhydride (ODPA) and pyromellitic dianhydride (PMDA) with the BATPO. The synthesized PIs exhibited outstanding thermal properties including high thermal decomposition temperatures (>500 degrees C) and glass transition temperature (T-g) in the range of 212-295 degrees C, and optical transparency at 450 nm of over 80% for films of ca. 10 mu m thickness. In particular, 3SDEA-BATPO exhibited a high refractive index (1.725) with low birefringence (0.0087) due to the heavy atom effect of the high sulfur and phosphorous contents in the polymer main-chain. (C) 2018 Elsevier Ltd. All rights reserved. 2018-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/121894 Title: RNA-guided single/double gene repressions in Corynebacterium glutamicum using an efficient CRISPR interference and its application to industrial strain Authors: Park, Jaehyun; SHIN HYOJUNG; Lee, Sun-Mi; Um, Youngsoon; Woo, Han Min Abstract: Background: The construction of microbial cell factories requires cost-effective and rapid strain development through metabolic engineering. Recently, RNA-guided CRISPR technologies have been developed for metabolic engineering of industrially-relevant host. Results: To demonstrate the application of the CRISPR interference (CRISPRi), we developed two-plasmid CRISPRi vectors and applied the CRISPRi in Corynebacterium glutamicum to repress single target genes and double target genes simultaneously. Four-different single genes (the pyc, gltA, idsA, and glgC genes) repressions were successfully performed using the CRISPRi vectors, resulting significant mRNA reductions of the targets compared to a control. Subsequently, the phenotypes for the target gene-repressed strains were analyzed, showing the expected cell growth behaviors with different carbon sources. In addition, double gene repression (the idsA and glgC genes in a different order) by the CRISPRi resulted in an independent gene repression to each target gene simultaneously. To demonstrate an industrial application of the CRISPRi, citrate synthase (CS)-targeting DM1919 (L-lysine producer) strains with a sgRNA-gltA-r showed reduced CS activity, resulting in the improvement of L-lysine yield by 1.39-fold than the parental DM1919 (a lysine producer). Conclusions: Single or double gene repression were successfully performed using the CRISPRi vectors and sequence specific sgRNAs. The CRISPRi can be applied for multiplex metabolic engineering to enhanced lysine production and it will promote the further rapid development of microbial cell factories of C. glutamicum. 2018-01-01T00:00:00Z