Dong-Gu Kim

International St. Mary's Hospitals, Chemulpo, Incheon, South Korea

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Publications (7)10.85 Total impact

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    ABSTRACT: There are three types of bile duct cancer, intrahepatic cholangiocarcinoma (ICC), hilar cholangiocarcinoma (HC), and extrahepatic cholangiocarcinoma (EHC). Despite different clinical presentation, the same protocol has been used in treatment of patients with these cancers. We analyzed clinicopathologic findings and protein expression in order to investigate the difference and the specific prognostic factors among these three types of cancers. We conducted a retrospective review of 104 patients diagnosed with bile duct cancer at Seoul St. Mary's Hospital between January 1994 and May 2004. We performed immunohistochemical staining for p53, cyclin D1, thymidine phosphorylase, survivin, and excision repair cross-complementing group 1 (ERCC1). Of the 104 patients, EHC was most common (44.2%). In pathologic findings, perineural invasion was significantly less common in ICC. Overall survival was similar among the three types of cancer. Lymph node invasion, lymphatic, and venous invasion showed a significant association with survival outcome in ICC, however, the differentiation of histologic grade had prognostic significance in HC and EHC. No difference in protein expression was observed among these types of cancer, however, ERCC1 showed a significant association with survival outcome in HC and EHC, not in ICC. Based on our data, ICC showed different characteristics and prognostic factors, separate from the other two types of bile duct cancer. Conduct of further studies with a large sample size is required in order to confirm these data.
    Preview · Article · Mar 2013 · Cancer Research and Treatment
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    ABSTRACT: Cellulose Electro-Active Paper (EAPap) is attractive as a biomimetic actuator because of its merits: it is lightweight, operates in dry conditions, has a large displacement output, has a low actuation voltage, and has low power consumption. Cellulose is regenerated so as to align its microfibrils, which results in a piezoelectric paper. When chemically bonded and mixed with carbon nanotubes, titanium oxide, zinc oxide, tin oxides, the cellulose EAPap can be used as a hybrid nanocomposite that has versatile properties and that can meet the requirements of many application devices. This paper presents trends in recent research on the cellulose EAPap, mainly on material preparation and its use in devices, including biosensors, chemical sensors, flexible transistors, and actuators. This paper also explains wirelessly driving technology for the cellulose EAPap, which is attractive for use in biomimetic robotics and micro-aerial vehicles.
    Preview · Article · May 2012 · Transactions of the Korean Society of Mechanical Engineers B
  • Dong-gu Kim · Sang-Youn Kim · Ki-Baek Kim · Jaehwan Kim
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    ABSTRACT: Over time, a wide variety of Haptic actuator have been designed and implemented to apply for mobile devices. This paper addresses an electrostatic actuator composed of an active film and patterned polydimethylsiloxane (PDMS) columns. A cellulose acetate (CA) film charged with an electric potential can generate vibration under the potential. The motion of the actuator is a concave and the actuator performance was modulated by increasing the bias level of the electric potential. The performance was evaluated depending on various actuation conditions in terms of electrical potential, bias voltage and frequency. It was found that the induced displacement of the actuator is proportional to the bias level of electric potential. Fast rising and falling behavior of the proposed haptic actuator can allow the generation of a vibrotactile sensation over a wide frequency range. The CA haptic actuator has a potential to generate a wide variety of tactile sensations.
    No preview · Article · Mar 2012 · Proceedings of SPIE - The International Society for Optical Engineering
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    Amalraj John · Hyun-U Ko · Dong-Gu Kim · Jaehwan Kim
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    ABSTRACT: Zinc oxide (ZnO) nanoparticles were immobilized on the surface of regenerated cellulose films by a wet chemical method in which the controlled hydrolysis of a Zn(II)-amine complex leads to the formation of ZnO nanoparticles. Cellulose-ZnO materials were characterized by spectral, thermal and optical methods. Scanning electron microscope and atomic force microscope analyses confirmed the formation of ZnO nanoparticles on the surface of the regenerated cellulose film and X-ray diffraction patterns showed the ZnO had the wurtzite structure. The reported method is very simple, and can immobilize the nanoparticles without the aid of a binder or dendritic side group and without high temperature treatments like calcination. ZnO immobilized on biopolymers like cellulose has many potential applications such as strain sensors, biomedical sensors, flexible display devices and optoelectronics.
    Full-text · Article · Jun 2011 · Cellulose
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    ABSTRACT: Haptic is one of well-considered device which is suitable for demanding virtual reality applications such as medical equipment, mobile devices, the online marketing and so on. Nowadays, many of concepts for haptic devices have been suggested to meet the demand of industries. Cellulose has received much attention as an emerging smart material, named as electro-active paper (EAPap). The EAPap is attractive for mobile haptic devices due to its unique characteristics in terms of low actuation power, suitability for thin devices and transparency. In this paper, we suggest a new concept of haptic actuator with the use of cellulose EAPap. Its performance is evaluated depending on various actuation conditions. As a result, cellulose electrostatic force actuator shows a large output displacement and fast response, which is suitable for mobile haptic devices.
    No preview · Article · Mar 2011 · Proceedings of SPIE - The International Society for Optical Engineering
  • Sang-Dong Jang · Dong-Gu Kim · Jaehwan Kim
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    ABSTRACT: In this paper, feasibility of a wireless mechanical strain sensor based on dipole antenna is investigated. The geometry, deformation and load impedance of feeding lines for dipole antenna can change the electromagnetic resonance frequency, magnitude of resonance and phase angle of antenna. Planar dipole antenna is designed for X band and made on a flexible polymer substrate is fabricated using a conventional photolithography process. Fabricated dipole antenna is attached to a plastic cantilever beam. The return loss of the dipole antenna sensor is characterized using a network analyzer. The strain sensitivity of the sensor is tested by correlating the return loss variation with the bending strain of the cantilever beam.
    No preview · Article · Mar 2011 · Proceedings of SPIE - The International Society for Optical Engineering
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    ABSTRACT: Survivin, an inhibitor of apoptosis is expressed in several human cancers. Its expression is known to be associated with poor clinical outcome, but not widely studied in pancreatic cancer. We performed this study to determine the survivin expression in pancreatic cancer and its clinical significance as a prognostic factor. We performed immunohistochemical staining for survivin, p53, and Bax in formalin-fixed, paraffin-embedded block from forty-nine pancreatic tissues. To determine the association with clinical course, we reviewed the patients' clinical record. Of the 49 cases of pancreatic cancer, 46 cases (93.9%) were positive for survivin expression. There was no significant association between survivin expression and p53 or bax. For clinicopathological parameters, perineural invasion was more common in survivin positive and venous invasion was more common in survivin negative (p = 0.041 and 0.040, respectively). Responsiveness to chemotherapy appeared to be slightly better in patients with low survivin expression. Survivin expression may be associated with venous or perineural invasion, indicating metastatic route, and seems to have a potential as a predictive marker for chemotherapy. Further study of large scale is required to determine the clinical significance of survivin expression in pancreatic cancer.
    Full-text · Article · Feb 2005 · BMC Cancer

Publication Stats

68 Citations
10.85 Total Impact Points


  • 2013
    • International St. Mary's Hospitals
      Chemulpo, Incheon, South Korea
  • 2011-2012
    • Inha University
      • Department of Mechanical Engineering
      Chemulpo, Incheon, South Korea
  • 2005
    • Catholic University of Korea
      • Department of General Surgery
      Sŏul, Seoul, South Korea