Yong Soo Lee

Bio: Yong Soo Lee is an academic researcher from Yonsei University. The author has contributed to research in topics: Photonic-crystal fiber & Optical fiber. The author has an hindex of 9, co-authored 29 publications receiving 254 citations. Previous affiliations of Yong Soo Lee include Gwangju Institute of Science and Technology.

Doxorubicin exerts cytotoxic effects through cell cycle arrest and Fas-mediated cell death

Abstract: Doxorubicin (DOX) is involved in the induction of DNA damage, inhibition of cell proliferation, impairment of mitochondria, and cell death. To determine the biological effects of DOX in murine lymphoc

Highly Birefringent and Dispersion Compensating Photonic Crystal Fiber Based on Double Line Defect Core

Abstract: We propose a highly birefringent and dispersion compensating photonic crystal fiber based on a double line defect core. Using a finite element method (FEM) with a perfectly matched layer (PML), it is demonstrated that it is possible to obtain broadband large negative dispersion of about -400 to -427 ps/(nm.km) covering all optical communication bands (from O to U band) and to achieve the dispersion coefficient of -425 ps/(nm.km) at 1.55μm. In addition, the highest birefringence of the proposed PCF at 1.55 μm is 1.92 x 10-2 and the value of birefringence from the wavelength of 1.26 to 1.8 μm (covering O to U bands) is about 1.8 x 10-2 to 1.92 x 10-2. It is confirmed that from the simulation results, the confinement loss of the proposed PCF is always less than 10-3 dB/km at 1.55 μm with seven fiber rings of air holes in the cladding.

Hollow Silica Photonic Crystal Fiber Guiding 101 Orbital Angular Momentum Modes Without Phase Distortion in C+L Band

Abstract: We propose a new hollow ring core silica photonic crystal fiber that can support 101 orbital angular momentum (OAM) modes, maintaining a high mode quality without phase distortion, a low confinement loss, and a large effective index difference between the adjacent modes, which could open a new avenue of OAM mode multiplexing applications. The fiber consists of three layers: the circular central air hole, silica ring core, and circumferencing silica-air hole porous inner cladding. Using the full-vectorial finite element method (FEM), the modal characteristics of individual OAM modes in the proposed fiber were thoroughly analyzed by varying the number of air-holes in the circularly symmetric cladding. We found a general selection rule for the number of air-holes in the first layer and the topological charge to cause the phase distortion of OAM modes, for the first time. The phase distribution of the guided OAM modes was thoroughly investigated to select usable modes for mode division multiplexing. Parametric analyses of the proposed PCF are reported to optimize optical properties of the OAM modes.

Controlled Intracellular Release of Doxorubicin in Multidrug-Resistant Cancer Cells by Tuning the Shell-Pore Sizes of Mesoporous Silica Nanoparticles

Abstract: In this work, hollow mesoporous silica nanoparticles (HMSNs) with three pore sizes were manufactured to control the drug release rate, and the biological roles of these HMSNs were evaluated in multidrug-resistant (MDR) cancer cells. As novel pore-size-controllable inorganic materials, HMSNs showed negligible cytotoxicity and efficient cellular uptake toward drug-sensitive MCF-7 and drug-resistant MCF-7/ADR cells. Doxorubicin (DOX)-loaded HMSNs (DMSNs) not only demonstrated effective drug loading and a pH-responsive drug release character but also exhibited pore-size-dependent and sustained drug release performance in both in vitro and intracellular drug release experiments. In addition, DMSNs exhibited pore-size-dependent anticancer activity against MCF-7/ADR cells. DMSNs with larger pore size could mediate more cellular uptake of DOX and faster intracellular drug release, which led to more intracellular drug accumulation and stronger MDR-reversal effects. The MDR-overcoming mechanism could be due to the efficient cellular uptake, P-gp inhibition, and ATP depletion. These results demonstrate that HMSNs could be a very promising drug delivery system for pore-size-controllable drug release and cancer MDR reversion.

Local radiation therapy inhibits tumor growth through the generation of tumor-specific CTL: its potentiation by combination with Th1 cell therapy.

Abstract: Radiation therapy is one of the primary treatment modalities for cancer along with chemotherapy and surgical therapy. The main mechanism of the tumor reduction after irradiation has been considered to be damage to the tumor DNA. However, we found that tumor-specific CTL, which were induced in the draining lymph nodes (DLN) and tumor tissue of tumor-bearing mice, play a crucial role in the inhibition of tumor growth by radiation. Indeed, the therapeutic effect of irradiation was almost completely abolished in tumor-bearing mice by depleting CD8(+) T cells through anti-CD8 monoclonal antibody administration. In mice whose DLN were surgically ablated or genetically defective (Aly/Aly mice), the generation of tetramer(+) tumor-specific CTL at the tumor site was greatly reduced in parallel with the attenuation of the radiation-induced therapeutic effect against the tumor. This indicates that DLN are essential for the activation and accumulation of radiation-induced CTL, which are essential for inhibition of the tumor. A combined therapy of local radiation with Th1 cell therapy augmented the generation of tumor-specific CTL at the tumor site and induced a complete regression of the tumor, although radiation therapy alone did not exhibit such a pronounced therapeutic effect. Thus, we conclude that the combination treatment of local radiation therapy and Th1 cell therapy is a rational strategy to augment antitumor activity mediated by tumor-specific CTL.