• IMMUNE NETWORK
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• v.12 no.6
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• pp.223-229
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• 2012

Clinical and preclinical in vivo immune cell imaging approaches have been used to study immune cell proliferation, apoptosis and interaction at the microscopic (intra-vital imaging) and macroscopic (whole-body imaging) level by use of ex vivo or in vivo labeling method. A series of imaging techniques ranging from non-radiation based techniques such as optical imaging, MRI, and ultrasound to radiation based CT/nuclear imaging can be used for in vivo immune cell tracking. These imaging modalities highlight the intrinsic behavior of different immune cell populations in physiological context. Fluorescent, radioactive or paramagnetic probes can be used in direct labeling protocols to monitor the specific cell population. Reporter genes can also be used for genetic, indirect labeling protocols to track the fate of a given cell subpopulation in vivo. In this review, we summarized several methods dealing with dendritic cell, macrophage, and T lymphocyte specifically labeled for different macroscopic whole-body imaging techniques both for the study of their physiological function and in the context of immunotherapy to exploit imaging-derived information and immune-based treatments.

• Journal of the Korean Data and Information Science Society
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• v.28 no.3
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• pp.669-684
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• 2017

Mediation models are widely used in many fields of research and have recently gained attention in epidemiology. The mediation proportion is a standard measure to evaluate what part of the total exposure effect on an outcome may be explained by a particular mediator and to examine how important that pathway is relative to the overall exposure effect. A common question is how large a sample size is needed to achieve high statistical power or, equivalently, what magnitude of effect can be detected. Current power and sample size calculations for mediation analysis are limited and additional research is needed. We therefore propose a computer-intensive power analysis using the mediation proportion. We conduct simulation studies to calculate statistical powers and sample sizes. And then, we illustrate our power analysis using an example from the Adult Health Study of atomic-bomb survivors and demonstrate that the method is relatively straightforward to understand and compute.

• Journal of the Korean Chemical Society
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• v.15 no.5
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• pp.256-265
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• 1971

An ESR study has been made on free radicals produced in frozen aqueous solutions (ices) of glycine, DL-${\alpha}$-alanine, DL-serine, L-cysteine, DL-leucine and DL-isoleucine by gamma-irradiation at dry ice temperature. All free radicals induced were decayed concomitant to the successive annealing but the radical species which is believed to be dominant seems to be stable even near the melting point of the ice. These dominant species were found to be identical to those resulted from direct action of radiation in the solid at room temperature. Small but significant changes in the spectra of glycine and DL-${\alpha}$-alanine were observed by varying the microwave power. These results seem to support the view that the spectra obtained were composite consisting of more than two different resonances having different power saturation characteristics. The relative contribution of unidentified resonances to the composite spectra was greater for solutions of low concentration. These resonances are assumed to be induced by indirect effects, mainly hydrogen abstraction by radiation produced hydroxyl radicals and also C-N bond cleavage by hydrated electrons.

• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.222-225
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• 2005

Stimulatory effects of near infra-red (NIR) rays radiation have been studied within the limits of photosynthesis, phototaxis, and photodermatology. While most of these studies have been done by direct NIR radiation, we investigated the effects of the NIR rays-treated materials on microbial growth. NIR in wavelength of 1,400${\~}$1,700 nm was applied for different kind of materials. Under fast growing conditions in rich media, materials treated with the NIR rays or not did not show any differences in growth of microorganisms. However, under slow growing conditions in minimal media, data showed that NIR rays-treated cloths and hygienic bands affect negatively on the growth of bacteria (Salmonella enteritidis) and fungi (Candida albicans). In addition, it was estimated that the effect of NIR rays on bacterial growth is kept going on S. enteritidis.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.4
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• pp.37-44
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• 2011

This paper was development of surface contamination automatic smear sampling for measuring radioactive contamination in radiation controlled area of nuclear facility. In indirect method a smear paper are used manually. Activity on the smear paper is affected by varying the pressures applied, by the smearing time, by the difference of ares sampled during smearing. By means of these there are erroneous. In the future the apparatus will be developed as a portable apparatus measuring smear activity automatically by adding radiation detection instrument.

• Biomedical Science Letters
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• v.12 no.1
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• pp.9-16
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• 2006

We investigated the effects of 835-MHz electromagnetic field (EMF), one of the most popular communication frequency band in Korean code-division multiple-access (CDMA) mobile phone system, on cellular signal transduction. For this, we examined the change of intracellular calcium $([Ca^{2+}]_i)$, reactive oxygen species (ROS) and F-actin polymerization after exposure to 835-MHz EMF followed by the treatment of agonists in Rat-2 fibroblast cells. Culture cells were pretreated with serum-tree medium and concomitantly exposed to 835-MHz at specific absorption rate (SAR) of 4.0 W/kg for 24 hr in a specialized designed apparatus based on Transverse Electro Magnetics (TEM) wave theory. Intracellular $Ca^{2+}$ responses to lysophosphatidic acid (LPA) and epidermal growth factor (EGF) in Rat-2 fibroblast after exposure to 835-MHz EMF were shown to be similar pattern as observed in normal cultured cells. However, the LPA-induced calcium spiking was slightly delayed to 7 sec and sustained thereafter to a little higher ground level under 835-MHz EMF radiation compared to unexposed cells. ROS production level by LPA in the exposed cells was not different from that in control. Furthermore, LPA induced the production of stress fibers with no significant difference in the exposed and unexposed cells. These results suggest that mobile phone radiation (835-MHz, SAR 4.0 W/kg) may not be directly related to signal transduction in Rat-2 fibroblasts except the slight effect of calcium spiking in LPA-induced cells but remain to be further elucidated for possible indirect intervention.

• Korean Journal of Medicinal Crop Science
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• v.19 no.4
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• pp.287-299
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• 2011

Pharmacological effects of Panax ginseng have been demonstrated in cardiovascular system, endocrine secretion and immune system, together with antitumor, anti-stress and anti-oxidant activities. Modern scientific data show protective effect of ginseng against bone marrow cell death, increased survival rate of experimental animals, recovery of hematopoietic injury, immunopotentiation, reduction of damaged intestinal epithelial cells, inhibition of mutagenesis and effective protection against testicular damages, caused by radiation exposure. And also, ginseng acts in indirect fashion to protect radical processes by inhibition of initiation of free radical processes and thus reduces the radiation damages. The research has made much progress, but still insufficient to fully uncover the action mechanism of ginseng components on the molecule level. This review provides the usefulness of natural product, showing no toxic effects, as an radioprotective agent. Furthermore, the further clinical trials on radioprotection of ginseng need to be highly done to clarify its scientific application. The effective components of ginseng has been known as ginsenosides. Considering that each of these ginsenosides has pharmacological effect, it seems likely that non-saponin components might have radioprotective effects superior to those of ginsenosides, suggesting its active ingredients to be non-saponin series. These results also show that the combined effects of saponin and non-saponin components play an important role in the radioprotective effects of ginseng.

• KSBB Journal
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• v.30 no.1
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• pp.11-20
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• 2015

Radiation causes various pathophysiological alterations in living animals, and it causes death at high doses by multiple mechanisms, including direct DNA damage and indirect oxidative stress. The search for useful radioprotectors has been an important issue in the field of radiation biology. Ideal radioprotectors should have low toxicity and an extended window of protection. As many synthetic compounds have toxic side effects, the natural products have attracted scientific attention as radioprotectors. Natural products that have been recently shown to be effective with various biological activities were found to have radioprotective effect. The aim of this review is to summary the recent research of the radioprotective effects of natural foods, especially focused on the glycobiological properties of mushrooms.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.5
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• pp.143-151
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• 2016

The aim of this study is to investigate the optimal algorithm to extract medical radiation induced pixel signal from complementary metal-oxide semiconductor (CMOS) sensors of smartphones camera. The pixel intensity and pixel number of smartphone camera were measured as the X-ray dose was increased. The front camera of the smartphone camera has low noise property and excellent dose response as compared to the back camera of the smartphone. The indirect method which uses scintillation crystal in front of the smartphone camera, couldn't improve the X-ray detection efficiency as compared to the direct method which does not use any scintillator in front of the smartphone camera. When we used the algorithm which employing threshold level on the pixel intensity and pixel number, the dose linearity was more higher for the pixel intensity rather for the pixel number. The use of pixel intensity of Y color component which represents the grey scale, would be efficient in terms of the radiation detection efficiency and reducing the complexity of the image processing. We expect that the radiation dose monitoring can be managed effectively and systematically by using the proposed radiation detection algorithm, thus eventually will contribute to the public healthcare.

• Journal of KSNVE
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• v.7 no.6
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• pp.975-984
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• 1997

A direct boundary element method (DBEM) is developed for thin bodies whose surfaces are rigid or compliant. The Helmholtz integral equation and its normal derivative integral equation are adoped simultaneously to calculate the pressure on both sides of the thin body, instead of the jump values across it, to account for the different surface conditions of each side. Unlike the usual assumption, the normal velocity is assumed to be discontinuous across the thin body. In this approach, only the neutral surface of the thin body has to be discretized. The method is validated by comparison with analytic and/or numerical results for acoustic scattering and radiation from several surface conditions of the thin body; the surfaces are rigid when stationary or vibrating, and part of the interior surface is lined with a sound-absoring material.