• Molecules and Cells
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• v.25 no.2
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• pp.305-311
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• 2008

After successful clinical application, arginine deiminase (ADI) has been proposed to be a new cancer therapeutic. In the present study, we examined the effect of ADI in combination with ionizing radiation (IR) on MCF-7 cell growth and clonogenic cell death. Cell growth was inhibited by IR in a dose-dependent manner and ADI enhanced the radiosensitivity. ADI itself did not suppress the growth of MCF-7 cells due to the high level of expression of argininosuccinate synthetase (ASS), which convert citrulline, a product of arginine degradation by ADI, to arginine. Previously, it was suggested that ammonia, another product of arginine degradation by ADI, is the main cause of the growth inhibition of irradiated hepatoma cells contaminated with ADI-expressing mycoplasma [van Rijn et al. (2003)]. However, we found that ammonia is not the only factor that enhances radiosensitivity, as enhancement was also observed in the absence of ammonia. In order to identify the enhancing effect, levels of ASS and proteins related to the cell cycle were examined. ASS was unchanged by ADI plus IR, but p21 (a CDK inhibitor) was upregulated and c-Myc downregulated. These findings indicate that changes in the expressions of cell cycle proteins are involved in the enhancement of radiosensitivity by ADI. We suggest that ADI is a potential adjunct to cancer therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5553-5565
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• 2013

Plants play important roles in human life not only as suppliers of oxygen but also as a fundamental resource to sustain the human race on this earthly plane. Plants also play a major role in our nutrition by converting energy from the sun during photosynthesis. In addition, plants have been used extensively in traditional medicine since time immemorial. Information in the biomedical literature has indicated that many natural herbs have been investigated for their efficacy against lethal irradiation. Pharmacological studies by various groups of investigators have shown that natural herbs possess significant radioprotective activity. In view of the immense medicinal importance of natural product based radioprotective agents, this review aims at compiling all currently available information on radioprotective agents from medicinal plants and herbs, especially the evaluation methods and mechanisms of action. In this review we particularly emphasize on ethnomedicinal uses, botany, phytochemistry, mechanisms of action and toxicology. We also describe modern techniques for evaluating herbal samples as radioprotective agents. The usage of herbal remedies for combating lethal irradiation is a green anti-irradiation approach for the betterment of human beings without high cost, side effects and toxicity.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.1957-1962
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• 2012

Bladder cancer is a common malignancy worldwide. Despite the increased use of cisplatin-based combination therapy, the outcomes for patients with advanced disease remain poor. Recently, altered activation of the PI3K/Akt/mTOR pathway has been associated with reduced patient survival and advanced stage of bladder cancer, making its upstream or downstream components attractive targets for therapeutic intervention. In the present study, we showed that treatment with DTCM-glutaramide, a piperidine that targets PDK1, results in reduced proliferation, diminished cell migration and G1 arrest in 5637 and T24 bladder carcinoma cells. Conversely, no apoptosis, necrosis or autophagy were detected after treatment, suggesting that reduced cell numbers in vitro are a result of diminished proliferation rather than cell death. Furthermore previous exposure to 10 ${\mu}g/ml$ DTCM-glutarimide sensitized both cell lines to ionizing radiation. Although more studies are needed to corroborate our findings, our results indicate that PDK1 may be useful as a therapeutic target to prevent progression and abnormal tissue dissemination of urothelial carcinomas.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.2
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• pp.11-18
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• 1989

Advancement of surgical techniques has made it necessary to accurately diagnose internal derangements. Arthrography and computerized tomography have been used to diagnose the majority of temporomandibular joint disorders, however, these methods have had their disadvantages. Magnetic resonance imaging utilizing surface coils has greatly improved the ability to diagnose meniscus abnormalities without using intrarticular injections or ionizing radiation. Ninety-two patients (184 joints) were evaluated by means of magnetic resonance imaging(MRI). Thirty-one patients (39 joints) were diagnosed as having meniscus perforation. Retrospective review of fifteen patients (20 joints) with a perforated meniscus diagnosed by magnetic resonance imaging pre-operatively demonstrated a sixty-five percent correlation between the radiographic diagnosis and the surgical findings.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.3
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• pp.189-197
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• 1993

Tempormandibular Joint pain and dysfunction is a common and important clinical problem. With the recent advances in imaging technology, radiologists have made major contribution to the understanding of TMJ disease. The MRI has several advantages over the conventional imaging methods. It is possible to obtain surprisingly precise images of internal hard and soft tissues with MRI. It is not invasive without ionizing radiation. The abnormal disk position has been thought as the cause of TMJ internal derangement. But there are few methods to relate disk position to TMJ internal derangement quantatively. The object of our study is to determine the amount of anterior displacement fo articular disk in symptomatic patients related each symptoms. Using the method of Dr. Drace, we studied the 38 joints of 22 persons with susceptable TMJ internal derangement. 1. In determining the anterior displacement of TMJ articular disk, the junction between the posterior band and bilaminar zone was useful. 2. The mean anterior displacement of disk in reduction group and without reduction group were $51.0^{\circ}C$ and $81.1^{\circ}C$ respectively. The difference was significant. 3. In the mean anterior displacement of disk, the pain without clicking group showed $84.8^{\circ}C$ and the clicking and pain group $70.8^{\circ}C$, the clicking group respectively.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.1
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• pp.23-30
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• 2015

Radioisotopes emitting low-range highly ionizing radiation such as ${\beta}$-particles are of increasing significance in internal radiotherapy. Among the ${\beta}$-particle emitting radioisotopes, $^{67}Cu$ is an attractive radioisotope for various nuclear medicine applications due to its medium energy ${\beta}$-particle, gamma emissions, and 61.83-hour half-life, which can also be used with $^{64}Cu$ for PET imaging. The production and application of the ${\beta}$-emitting radioisotope $^{67}Cu$ for therapeutic radiopharmaceutical are outlined, and different production routes are discussed. A survey of copper chelators used for antibody labeling is provided. It has been produced via proton, alpha, neutron, and gamma irradiations followed by solvent extraction, ion exchange, electrodeposition. Clinical studies using $^{67}Cu$-labelled antibodies in lymphoma, colon carcinoma and bladder cancer patients are reviewed. Widespread use of this isotope for clinical studies and preliminary treatments has been limited by unreliable supplies, cost, and difficulty in obtaining therapeutic quantities.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.8
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• pp.483-488
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• 2016

Ultrasound imaging by using piezoelectric materials, such as lead zirconium titanate (PZT) has been one of the most preferred modes of imaging in the medical field due to its simple, low cost and non-ionizing radiation in comparison to other imaging techniques. Recently, the market demand for portable ultrasound is becoming larger with applications in developing countries, disaster area, military, and emergency purposes. However, most of ultrasound probes used is bulky and high power consumable, so unsuitable for such applications. In this study, the 3 layered ceramic specimen consisted of 128 pitches of $420{\mu}m$ in width and $450{\mu}m$ in thickness were prepared by using the Ti-rich PZT compositions co-fired at $1,050^{\circ}C$. Their electrical and ultrasound pulse-echo properties were investigated and compared to the single layer specimen. The 3 layered ultrasound probe showed 1.584 V of Vp-p, which is 3.2 times higher than single layered one, implying that it would allow effectively such a portable ultrasound probe system. The result were discussed in terms of higher capacitance, lower impedance and higher dielectric coefficient of the 3 layered ultrasound probe.

• Journal of Digital Convergence
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• v.14 no.1
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• pp.305-310
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• 2016

Recently as the ultrasonography became generalized, the annual change rate of the incidence of thyroid cancer extraordinarily grew to 24.5% in Korea. Therefore, the aim of this study was performed to identify the risk factors of thyroid cancer apart from conventional risk factors of dietary iodine and ionizing radiation. In this retrospective study, 411 patients underwent fine-needle aspiration biopsy were examined from January 2011 to March 2013. The subjects are divided into two groups which are 260 patients with benign nodule and 151 patients with malignancy nodule. We compared age, hematologic values, body mass index, waist circumference, menopausal status, breast nodules status, uterine myoma status, fatty liver status of targeted group of patients. According to the result, in thyroid cancer group with obesity, the number of case of breast nodules and myoma was higher, and their thyroid stimulating hormone values was higher than the benign nodule group. In order to establish factors influencing thyroid and thyroid cancer, there is a definite need for continuous study.

• Korean Journal of Veterinary Research
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• v.44 no.3
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• pp.323-327
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• 2004

The purpose of the present experiment was to investigate the micronuclei(MN) frequency in cytokinesis-blocked(CB) cells after various doses of gamma-rays in pig (Landrace, male, 3-month-old) and so to contribute to the clarification of the question whether these species are suitable as a target organism in the test system. The frequencies of binucleated cells, and gamma-ray-induced MN in CB cells at several doses were measured in three donors. The peaks of binucleated lymphocyte formation(22%) were found at a concentration of 2% phytohaemagglutinin(PHA) and $4{\mu}g/ml$ Cytochalasin B(Cyt-B) in pig at 72 hours after incubation. Measurements performed after irradiation showed a dose-related increases in MN frequency in each of the donors studied. When analysed by linear-quadratic model the line of best fit was $y=0.0183D+0.0124D^2+0.0133$(y = number of MN/CB cells and D=irradiation dose in Gy). In conclusion, the results demonstrate that it appears feasible to use pig as target organisms in the micronucleus test to estimate the cytogenetic damage caused by ionizing radiations or, potentially, chemical compounds.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.1
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• pp.106-112
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• 2013

In this paper, human exposure of wireless devices was analyzed for various positions of the transmitter. The scenario for the position of the transmitting antenna was decided after discussion with ADD(Agency for Defense Development), and Korean male phantom model developed by ETRI were used to conduct simulations. The SAR values were analyzed by changing the position of the transmitter, and compared with Korean EMF regulations and ICNIRP guidelines. Additionally, human exposure was also investigated for two typical postures which can be posed by war-fighter.