Surface-Induced Self-Assembly and Fibrillation of Prion Peptide

Sook Hee KU,Chan Beum PARK 한국생물공학회 2009 한국생물공학회 학술대회 Vol.2009 No.4

Tumor-Targeting Multifunctional Nanoparticles for siRNA Delivery: Recent Advances in Cancer Therapy

Ku, Sook Hee,Kim, Kwangmeyung,Choi, Kuiwon,Kim, Sun Hwa,Kwon, Ick Chan Wiley (John WileySons) 2014 Advanced Healthcare Materials Vol.3 No.8

<P>RNA interference (RNAi) is a naturally occurring regulatory process that controls posttranscriptional gene expression. Small interfering RNA (siRNA), a common form of RNAi-based therapeutics, offers new opportunities for cancer therapy via silencing specific genes, which are associated to cancer progress. However, clinical applications of RNAi-based therapy are still limited due to the easy degradation of siRNA during body circulation and the difficulty in the delivery of siRNA to desired tissues and cells. Thus, there have been many efforts to develop efficient siRNA delivery systems, which protect siRNA from serum nucleases and deliver siRNA to the intracellular region of target cells. Here, the recent advances in siRNA nanocarriers, which possess tumor-targeting ability are reviewed; various nanoparticle systems and their antitumor effects are summarized. The development of multifunctional nanocarriers for theranostics or combinatorial therapy is also discussed.</P>

Behavioral Response of Termites to Tunnel Intersection

Sook Jung Ku,Sheon-Young Kang,Nan-Yao Su,Sang-Hee Lee 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.05

Subterranean termites construct complicated tunnel network for foraging below the ground. Thus, they often encounter a number of tunnel intersections during their moving from place to place in the network. In order to understand how termites respond to the intersections, we artificially excavated two tunnels intersected with 90° degree in soil-filled arenas. The two tunnels had the width of W1 and W2 (=2, 3, and 4mm), respectively. We systematically observed the response behavior of advancing termites to the intersection with the combination of W1 and W2, (W1, W2). For (W1, W2)=(2, 2) and (3, 3), the advancing termites passed the intersection without directional changes because it was difficult for termites to bend their body to change their moving direction due to the small-sized width. For (W1, W2)=(4, 4), the termites statistically-equally chose the three directions, left, right, and straight, which was due to the fact that the intersection provided enough space for termites to bend. For (W1, W2)=(2, 3), (2, 4), and (3, 4), termites, advancing in narrower tunnels, tended considerably to turn right or left, while termites, advancing in wider tunnels, were favorably inclined to go straight. These results can be understood by considering the relationship between termite body length and tunnel width as explained for the cases of W1=W2. In addition, we briefly discussed our findings in relation to termite foraging efficiency.

Carbon-based nanomaterials for tissue engineering.

Ku, Sook Hee,Lee, Minah,Park, Chan Beum Wiley-VCH 2013 Advanced healthcare materials Vol.2 No.2

<P>Carbon-based nanomaterials such as graphene sheets and carbon nanotubes possess unique mechanical, electrical, and optical properties that present new opportunities for tissue engineering, a key field for the development of biological alternatives that repair or replace whole or a portion of tissue. Carbon nanomaterials can also provide a similar microenvironment as like a biological extracellular matrix in terms of chemical composition and physical structure, making them a potential candidate for the development of artificial scaffolds. In this review, we summarize recent research advances in the effects of carbon nanomaterial-based substrates on cellular behaviors, including cell adhesion, proliferation, and differentiation into osteo- or neural- lineages. The development of 3D scaffolds based on carbon nanomaterials (or their composites with polymers and inorganic components) is introduced, and the potential of these constructs in tissue engineering, including toxicity issues, is discussed. Future perspectives and emerging challenges are also highlighted.</P>

Analysis of the Responses of Termites to Tunnel Irregularity

Sang-Hee Lee,Sook Jung Ku 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.04

Subterranean termites build extensive underground galleries consisting of elaborate tunnels and channels to forage food resources. Diverse soil conditions surrounding the tunnels, such as soil density, may cause irregularities in the size and shape of the tunnels, and termites are likely to encounter a number of tunnel irregularities while traveling. Considering the tunnel length, how termites respond to an irregularity is likely to affect their movement efficiency, and this in turn is directly correlated to their foraging efficiency. To understand the response of termites, we designed an artificial linear tunnel with rectangular irregularities in a 2-D arena. The tunnel widths, W, were 3 and 4 mm. The rectangular irregularities were 2 mm in width and of varying heights H (2, 1, 0, -1, and -2 mm). The positive and negative sign of H represents a convex and concave structure, respectively. We systematically observed the movement of termites, Coptotermes formosanus Shiraki, at the irregularity and quantified the time needed, τ, for a termite to pass the irregularity. The time τ was shorter for (W, H) = (3, 0) and (3, -1) than for (W, H) = (3, 1), (3, 2), and (3, -2). The time τ was longer for (W, H) = (4, -1), and (4, -2), than for (W, H) = (4, 0), (4, 1) and (4, 2). Four types of behaviors explained the response to the irregularity. The implications of these findings are briefly discussed in relation to termite foraging efficiency.

Fucoidan의 멜라닌 합성과 tyrosinase 활성도 억제 효과

정숙희(Sook Hee Jung),구미정(Mi Jung Ku),문희정(Hee Jung Moon),유병철(Byeng Chul Yu),전만중(Man Joong Jeon),이용환(Yong Hwan Lee) 한국생명과학회 2009 생명과학회지 Vol.19 No.1

미역, 다시마 등 갈조류의 추출물로서 생리활성성분으로 각광 받고 있는 fucoidan이 멜라닌 합성에 미치는 영향을 알아봄으로써 미백제로서의 개발 가능성 여부를 확인하기 위하여 B16F10 melnoma 세포를 이용하여 멜라닌 합성과 tyrosinase 활성도에 대한 실험의 결과 B16F10 melnoma 세포의 멜라닌 생성과 tyrosinase 활성도는 fucoidan의 농도가 증가함에 따라 농도 의존적으로 억제되었다. B16F10 melnoma 세포에 α-MSH를 투여 후 멜라닌 생성과 tyrosinase의 활성도 역시 fucoidan의 농도가 증가할수록 멜라닌 생성과 tyrosinase활성도가 억제되는 경향을 보였다. 또한 DOPA 염색의 결과 fucoidan은 농도 의존적으로 tyrosinase 활성도를 억제하였다. 이상의 결과 해조 추출 다당류인 fucoidan은 B16F10 melanoma 세포의 멜라닌 합성과 tyrosinase 활성도 억제 작용을 나타내므로 미백 활성 물질로서의 가능성을 가지고 있는 것으로 생각된다. Melanogenesis is a physiological process that results in the synthesis of melanin pigments. Tyrosinase is a key enzyme for melanin biosynthesis, and hyperpigmentation disorders are associated with abnormal accumulation of melanin pigments, which can be improved by treatment with depigmenting agents. Among the possible melanin-reducing compounds, tyrosinase inhibitors are most promising for preventing and treating pigmentation disorder and are used as skin-whitening agents in the cosmetic industry. In the present study, the effects of fucoidan on melanogenesis and tyrosinase activity of B16F10 melanoma cells were investigated. Melanin synthesis and tyrosinase activity in B16F10 melanoma cells were decreased in a dose-dependent manner by fucoidan. Melanin production and tyrosinase activity in B16F10 melanoma cells stimulated by α-melanocyte stimulating hormone (α-MSH) were inhibited by fucoidan with a dose-dependent manner compared to control. Fucoidan inhibited tyrosinase activity of B16F10 melanoma cells with a dose-dependent manner as assessed by 3,4-dihydroxyphenylalanine (DOPA) staining. In conclusion, these findings indicate that fucoidan, which inhibit melanin synthesis and tyrosinase activity, is an effective skin-whitening agent.

産婦人科領域에서의 細胞遺傳學 : 原發性無月經患者의 染色體觀察 with cytogenetic study in primary amenorrhea

丘秉參,金淑姬 고려대학교 의과대학 1984 고려대 의대 잡지 Vol.21 No.2

The present article was reviewed the developmental process of cytogenetics and its valuable contributions toward the practices of Obsterics and Gynecology. In addition to it's review, a cytogenetic study of 32 primary amenorrhea patients was carried out using the peripheral lymphocyte culture. Ten of 32 specimens (31.2 percent) showed a chromosomal abnormalities, so the results of chromosomal analysis was presented.

과배란유도주기에서 난포액내의 Prolactin치와 난자성숙도 및 수정에 관한 연구

김숙희,이규완,구병삼,홍성봉 고려대학교 의과대학 1988 고려대 의대 잡지 Vol.25 No.1

Aiming at furthering In Vitro Fertilization program, the levels of prolactin and several other hormones in follicular fluids obtained from 31 infertile women were assessed. In addition, size and volume of each follicles were also measured. In each cases clomiphene citrate, human menopausal gonadotropin and human chorionic gonadotropin were instituted before the aspiration of follicles. 64 oocytes retrieved from the follicles in hyperstimulated ovary were classified by the degree of maturity. Finally, correlation of follicular size, follicular volume and intrafollicular prolactin and other hormones with the degree of oocytes maturity were evaluated. The results were obtained as follows: 1. The levels of prolactin was much higher in follicular fluid of the mature and intermediate oocytes than in those of the immature oocyte. 2. The levels of FSH, estradiol and progesterone were much higher in the follicular fluid of the mature and intermediate oocyte than those of the immature oocyte. However, the leyels of testosterone in follicular fluid of mature and intermediate oocytes were significantly much less than those in the immature oocytes. 3. There was positive correlation between prolactin, and other hormones such as FSH, estradiol and progesterone levels in follicular fluid, but a significant negative correlation between prolactin and testosterone levels in follicular fluids. 4. There was a positive correlation between follicular diameter and oocyte maturity and no correlation between follicular fluid volueme and oocyte maturity. 5. There was a significant positive correlation between prolactin levels in follicular fluid and follicular diameter, but no correlation between prolactin levels and follicular volume, 6. The levels of prolactin, FSH, estradiol, and progesterone in follicular fluid of fertilized oocytes were significantly higher than those of not fertilized oocyte. On the contrary, testosterone levels in follicular fluid of not fertilized oocyte was significantly higher than those of fertilized oocyte.

Deoxycholic acid-modified polyethylenimine based nanocarriers for RAGE siRNA therapy in acute myocardial infarction

구숙희,Sook Hee Ku,문현호,Ji Hoon Jeong,목혜정,박성하,최동훈,김선화 대한약학회 2015 Archives of Pharmacal Research Vol.38 No.7

The activation of receptor for advanced glycation end products (RAGE) signaling is mainly associated with myocardial ischemia/reperfusion injury. Thus the blockade of RAGE-ligands axis can be considered as a potential therapeutic strategy to protect myocardial infarction after ischemia/reperfusion injury. Herein, we strengthened the cardioprotective effect with combinatorial treatment of soluble RAGE (sRAGE) and RAGE siRNA (siRAGE) causing more effective suppression of RAGEmediated signaling transduction. For pharmacological blockadeofRAGE,sRAGE,theextracellularligandbinding domain of RAGE, acts as a pharmacological ligand decoy and inhibits the interaction between RAGE and its ligands. For genetic deletion of RAGE, siRAGE suppresses the expression of RAGE by participating in RNA interference mechanism. Therefore, we combined these two RAGE blockade/deletionstrategiesand investigated thetherapeutic effects on rat ischemic and reperfused myocardium. According to our results, based on RAGE expression level analysis and infarct size/fibrosis measurement, co-treatment of sRAGE and siRAGE exhibited synergic cardioprotective effects; thus the newly designed regimen can be considered as a promising candidate for the treatment of myocardial infarction.

A Study of the Diagnostic Efficacy of Magnetic Resonance Elastography according to the Change in SENSE Reduction Factor

Jun-Hee Choi,Ji-Sook Yu,Geon-Yeong Kim,Yong-Ju Kim,Yong-Sik Bang,Hong-Uk Ku 대한자기공명기술학회 2021 대한자기공명기술학회지 Vol.31 No.1