• Journal of electromagnetic engineering and science
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• v.9 no.4
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• pp.188-193
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• 2009

A K-band low-power miniaturized planar-type hyperthermia system was developed to replace massive and expensive equipment. The system consists of a VCO with a buffer amplifier, a high-power amplifier module, a 20-dB-coupled line coupler, a chip circulator and two power detectors for signal generation, amplification and power monitoring. All these components have been implemented in planar form on two module blocks. The total size of the hyperthermia system was less than $10\times6.5\times3\;cm^3$. In order to verify the system performance, ablations were carried out on nude mice xenografted with human breast cancer. Ablation results show performance comparable to the massive components-based system. This work shows the feasibility of a low-cost miniaturized hyperthermia system for practical clinical applications.

• Radiation Oncology Journal
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• v.6 no.1
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• pp.75-80
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• 1988

Twenty seven lesions of 25 patients with locally advanced malignant tumors were treated with combined hyperthermia introduced by microwave and ultrasound and radiotherapy. Most of all patients were failed with previous conventional therapeutic trial. Hyperthermia had been done immediately after radiotherapy, twice a week, $43^{\circ}C$ for one hour and radiotherapy had been done 5 fractions per week with fraction size of 2Gy upto 30 to 60Gy. Conclusions are as follows. 1. Total response rate (PR+PR) to thermoradiotherapy with microwave and ultrasound was $81\%$. 2. Tumor depth, minimum temperature of tumor center, number of heat fraction and radiation dose were statistically significant factors affecting response. 3. Hyperthermia with microwave and ultrasound can be used efficiently to control locally advanced malignant disease whether previously received near tolerance dose of radiotherapy or not.

• Journal of Korean Medicine for Obesity Research
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• v.16 no.2
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• pp.133-137
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• 2016

This study was conducted to investigate the effects of wild ginseng complex (WGC) pharmacopuncture combined with hyperthermia on abdominal obesity in post-menopause women. Two post-menopausal women were treated 5 times in 2 weeks with WGC pharmacopuncture on abdominal acupoints and 30 minutes of hyperthermia on abdominal area. Before treatment and after 5 treatments were finished, body weight (BW), body mass index (BMI), body fat ratio, waist circumference (WC), waist hip ratio, thickness of abdominal subcutaneous fat (ASF) were measured. In case 1, BW, BMI, WC, and ASF were reduced by 0.6 kg, $0.2kg/m^2$, 6 cm, and 18 mm respectively. In case 2, BW, BMI, WC, and ASF were reduced by 0.4 kg, $0.17kg/m^2$, 4.6 cm, and 12 mm respectively. This suggest that combined therapy of WGC pharmacopuncture and hyperthermia might be an effective treatment for abdominal obesity in post menopause women.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.7.1-7.1
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• 2009

The use of Duplex stainless steel as a thermo-implant categorizes into two clinical applications: hyperthermia and thermal ablation or destruction. The goal of hyperthermia is to destroy the heat-sensitive abnormal cells and minimize normal cell death maintaining heat between $42^{\circ}C$ and $46^{\circ}C$. Thermal ablation takes place when the local tissue temperature increases greater than $46^{\circ}C$. This elevated temperature denatures protein irreversibly resulting cellular death. The author introduced several thermo-implants such as thermo-rod, thermo-stent, thermo-coil and thermoacupuncture-needle. Those thermo-implants are made of duplex stainless steel which can produce regulated heat by itself within an induction magnetic field. Thermal ablation characteristics of the thermo-rod on tumor hyperthermia depend on configurations of the thermo-rods and the magnitude of the induction magnetic strength. The exothermic properties of the thermo-implants can be characterized using the calorimetric test and the heat affected zone(HAZ) analyses in vitro. Thermal radiation studies using thermo-coils and thermo-stents show the capability of the occlusion of animal blood vessels and inhibiting the proliferation of the abnormal smooth muscle cell growth and inflammatory cell reactions maintaining the heat between $42^{\circ}C$ and $46^{\circ}C$ minimizing a normal cell death in the study on external iliac artery of the New Zealand White (NZW) rabbit. Thermal stimulation study using thermo-acupuncture needles suggests the potential applications of the automated acupunctural therapies.

• Journal of the Korean Physical Society
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• v.73 no.9
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• pp.1334-1339
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• 2018

Spherical nickel ferrite nanoparticles were synthesized using the thermal decomposition method and coated with cetyl trimethyl ammonium bromide (CTAB) after the synthesis. Transmission electron microscopy images showed that the average diameter of the particles was 9.40 nm. The status of the CTAB-coating on the surface of the particles was checked using Fourier-transform infrared spectroscopy. Their hysteresis curve showed that the particles exhibited a superparamagnetic behavior. The $T_1$ and the $T_2$ relaxations of the nuclear spins were observed in aqueous solutions of the particles with different particles concentrations by using a magnetic resonance imaging (MRI) scanner, which showed that the $T_1$ and the $T_2$ relaxivities of the particles in water were $0.57mM^{-1}{\cdot}s^{-1}$ and $10.42mM^{-1}{\cdot}s^{-1}$, respectively. In addition, using an induction heating system, we evaluated their potentials for magnetic hyperthermia applications. The aqueous solution of the particles with a moderate concentration (smaller than 6.5 mg/mL) showed a saturation temperature larger than the hyperthermia target temperature of $42^{\circ}C$. These findings show that the CTAB-coated nickel ferrite particles are suitable for applications as $T_2$ contrast agents in MRI and heat generators in magnetic hyperthermia.

• The Journal of the Acoustical Society of Korea
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• v.5 no.4
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• pp.46-56
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• 1986

Hyperthermia를 사용하여 종양세포를 치료하는데 있어서 시간에 따른 동적 온도분포를 추정하 고 또, 그 온도분포에 관계하는 인자들이 동적 온도특성에 미치는 영향을 살펴보는 것은 실제 치료시에 정확한 온도제어를 위해서 반드시 필요하다. 본 논문에서는 몸속 10cm 깊이에 존재하는 원통형 종양모 델을 설정하고 초음파 동심환 변환기로 열을 집속시켰을 때 동적 온도분포 추정을 위해서 2차원 유한요 소법과 유한차분법을 이용하였다. 결과로서, 동적 온도분포에 가장 큰 영향을 미치는 인자는 혈류량이었 고, 추출된 동적 온도분포 특성값을 가지고 간단한 ON/OFF 온도제어에 적용할 수 있음을 보였다.

• The Journal of the Acoustical Society of Korea
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• v.5 no.4
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• pp.37-45
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• 1986

초음파 Hyperthermia를 이용한 치료는 정상세포에 열적 손상을 주지 않으면서 종양 부위만을 적당한 온도로 가열하여야 하며 따라서 종양세포와 정상세포에 대한 정확한 초음파 세기조절이 필요하 게 된다. 본 논문에서는 초음파 Hyperthermia 용 변환기로서 초점거리와 가열범위를 전자적으로 쉽게 조절할 수 있는 동심환 배열 변환기를 설계하였으며 컴퓨터 모의 실험을 통해 그 성능을 예측하였다. 설계된 변환기는 유효직경 118mm, 동작주파수 320kHz 이며 배열 요소의 수는 12개이다. 그리고 이와 같은 동심환 변환기를 동작시키기 위해 카운터를 이용한 디지털 위상 조절 회로를 설계 제작하였으며, 실험 결과, 위상차를 갖는 신호를 발생시킬 수 있었다.

• Journal of Biomedical Engineering Research
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• v.8 no.1
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• pp.63-68
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• 1987

The biological effects for the use of hypertherinla to treat malignant tumors has been well studied and encouraging clinical results have been reported. However, the engineering and technical aspects of hyperthermia for the deepseated tumors has not been satisfactory. We have developed the FF capacitive hyperthermia device(GHT RF8)by cooporation with Yonsei Cancer Center and Green Cross Medical Equipment Corporation. It was composed with 8.10 MHz RF generator, capacitive electrode, matching system, cooling system, temperature measuring thermocouples and control PC computer. We have measured the temperature and thermal distribution in agar phantom, animals and human tumors.

• The Journal of the Acoustical Society of Korea
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• v.6 no.1
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• pp.29-38
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• 1987

In clinical applications of hyperthermia, temperatures can be measured at only a few locations, whereas accurate temperature profiles need to be known for efficient therapy. For doing this, bio-heat transfer equation was modified into 1 dimensional 2 boundary value problem for simplicity and the efficiency of time, and solved by Galerkin's method. The results were then applied to annular array transducer for both the calculation of its axial temperature distribution and the estimation of temperature profiles from a few measured temperature data.

• Journal of the Korean Society of Combustion
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• v.16 no.2
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• pp.33-39
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• 2011

We demonstrated heat generation efficiency of the magnetic hyperthermia system to find optimal condition using gelatin tissue phantom. Magnetic hyperthermia induction can be used to make heat generation with different concentration of $Fe_3O_4$ iron oxide inside tissue phantom and magnetically labeled cells by applying AC magntic field at a frequency of 145 kHz. It was observed that the maximum temperature achieved in the magnetic gelatin tissue phantom increased with the concentration of $Fe_3O_4$ iron oxide and alternating magnetic field intensity. Results were discussed with respect to further optimization of therapeutic technique for biomedical application with modified functional nanoparticles.