• Biomedical Science Letters
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• v.21 no.2
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• pp.51-59
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• 2015

A humanized mice (hu-mice) model is extremely valuable to verify human cell activity in vivo condition and is regarded as an important tool in examining multimodal therapies and drug screening in tumor biology. Moreover, hu-mice models that simply received human $CD34^+$ blood cells and tissue transplants are also overwhelmingly useful in immunology and stem cell biology. Because generated hu-mice harboring a human immune system have displayed phenotype of human $CD45^+$ hematopoietic cells and when played partly with functional immune network, it could be used to evaluate human cell properties in vivo. Although the hu-mice model does not completely recapitulate human condition, it is a key methodological factor in studying human hematological malignancies with impaired immune cells. Also, an advanced humanized leukemic mice (hu-leukemic-mice) model has been developed by improving immunodeficient mice. In this review, we briefly described the history of development on immunodeficient SCID strain mice for hu-and hu-leukemic-mice model for immunologic and tumor microenviromental study while inferring the potential benefits of hu-leukemic-mice in cancer biology.

• The Journal of Korean Society of Virology
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• v.27 no.2
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• pp.185-195
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• 1997

Sequence comparison of the RNA-dependent RNA polymerase of human caliciviruses (HuCVs) from Korean children with gastroenteritis revealed significant genetic variation among them. cDNA clones were produced from the HuCVs collected from pediatric population during a period of 1987-1994. The application of reverse transcription-polymerase chain reaction (RT-PCR) using primers directed to the RNA-dependent RNA polymerase region within ORF1 of Norwalk virus (NV) showed that 13.7% of HuCVs yielded PCR products of similar size to the NV prototype, NV8FIIa/68/US, with exceptions of HuCV 185/87/Korea and HuCV 1115/90/Korea. Computer analyses showed that the PCR products had a continuous protein encoding frame on the positive strand, and contained GLPSG and YGDD amino acid motifs at the predicted distance from primers. Alignment of the amino acid sequences of HuCVs with previously published sequences for Snow Mountain agent (SMA), NV, and Sapporo/82/Japan indicated that these strains can be divided into four major genogroups. There were 10 (45%) SMA-like CVs, one (4.5%) NV-like HuCVs, two (9%) Sapporo-like HuCVs, and nine (41%) unidentified HuCVs. This fourth genogroup should be investigated further. HuCV 185/87/Korea and HuCV 1115/90/Korea, Sapporo-like CVs, were genetically distinct from previously characterized HuCVs and more closely related to known animal CVs. One of the animal CV-like strain, HuCV 185/87/Korea, showed nucleotide and amino acid homology of only 67% and 73% with the prototype Sapporo/82/Japan. Further characterization of animal and human CV genomes and studies of possible cross-transmission of CVs from animals to humans are likely to be beneficial in understanding the epidemiology of HuCVs.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.183-189
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• 2014

Purpose : Intravenous contrast medium is a substance used to enhance the contrast of normal tissues or malignant tissues within the body. For this reason, intravenous contrast media have been extensively used form treatment-planning CT. However, when the patient is receiving proton therapy, there is no contrast medium in that moment. In this study, evaluate the influence of intravenous contrast medium on proton range and Spread-Out Bragg peak(SOBP) in Treatment Planning System(TPS). Materials and Methods : Hounsfield Unit(HU) value were measured by 20 liver cancer patients with phase change. and evaluate the proton range and SOBP on 5 liver proton treatment plan. By using the hand made water phantom measure the proton range and SOBP on proton treatment plan with changing HU and Depth. Results : Changing value(Pre contrast, Arterial phase, Portal phase) in liver cancer patient were ($58{\pm}5.7$, $75{\pm}9.5$, $117{\pm}14.6$ for liver tissue) and ($40{\pm}6.1$, $279{\pm}49.0$, $154{\pm}22.8$ for aorta), respectively. The mean difference of range was 2.5mm and SOBP was 1.4mm according to HU change. In phantom study, proton range was shorter and SOBP was narrowed with increasing HU. Conclusion : We verify that HU change lead to range and SOBP change in TPS. Additional study is required to verify that change of HU make range and SOBP be changed in actual substance.

• Journal of Pharmaceutical Investigation
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• v.17 no.4
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• pp.213-216
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• 1987

The distribution features of recombinant human $alpha-interferon(rHuIFN-{\alpha}A)$ and $^{14}C-radiolabeled\;rHuIFN-{\alpha}A\;(^{14}C-rHuIFN-{\alpha}A)$ were investigated in ICR mice after i.v. injection. The level of $rHuIFN-{\alpha}A$ in the kidney was significantly higher than those in lung and liver at 10min after the injection. But the level was reduced significantly at 60min. The level of radioactivity in the kidney was also significantly higher than those in other organs after i.v. injection of $^{14}C-rHuIFN-{\alpha}A$, but it was reduced at much slower speed than was $rHuIFN-{\alpha}A$. These results show that interferon is distributed repidly and the kidney is the main site of distribution and metabolism of $rHuIFN-{\alpha}A$.

• Toxicological Research
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• v.21 no.3
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• pp.209-218
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• 2005

We investigated effects of recombinant human erythropoietin (rHuEPO) on profiles of mRNA transcripts in 6 male cynomolgus (M. fascicularis) monkey's spleen for 4 weeks. Six monkeys, composed of control and treatment group (Control : M1, M2, M3: Treatment : M4, M5, M6) were intravenously administered 3 times per week without or with a dose of rHuEPO 2730 IU/0.1 ml/kg. After 4 weeks rHuEPO treatment, spleen was removed for RNA isolation. Splenic gene expression was assessed using Affymetrix U133A 2.0 arrays containing 18,400 transcripts and variants, including 14,500 well-characterized human genes. Gene expression pattern was very different between individuals even in same treatment. In rHuEPO treated groups showed number of genes were up- or down-regulated (M4: 79: M5: 48; M6: 73 genes). Six genes (epidermal growth factor receptor, calgranulin A, estrogen receptor binding site associated antigen, matrix metalloproteinase 19, zinc finger and BTB domain containing 16, progestin and adipoQ receptor) were commonly expressed in rHuEPO treated group. The different individual response could be major considering factor in monkey experiment. Further study is needed to clarify the different individual response to rHuEPO in molecular level. This study will be valuable in the fundamental understanding and validation of molecular toxicology for bio-generic drugs including rHuEPO in cynomolgus monkey.

• Progress in Medical Physics
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• v.20 no.3
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• pp.145-151
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• 2009

This study aims to evaluate CT (Computed Tomography) characteristics through the estimation of HU (Hounsfield Unit) and the corresponding variations using coefficient of variation values for various materials as a function of physical factor. HU values for various materials with varying densities as a function of physical factor were measured using MDCT (Siemens SOMATOM Sensation 4, Germany). The results showed that the HU values were decreased and increased as a function of kVp and material density, respectively. Especially, the HU values for bone and iodine at 140 kVp were 32% and 42% smaller than those at 80 kVp, respectively. In case of iodine, the HU values also decreased and increased as a function of kVp and concentration, respectively. While the HU values were fixed as a function of mAs. The decreased ratio of HU values between 80 keV and 140 keV was different at various concentration and maximum difference was shown as 1.73 at 3% concentration. These results indicated that it may be possible to separate composition of materials, e.g. iodine and bone, using single source CT. The results showed that dual energy techniques using single source CT can be applied to material separation and expand CT imaging techniques to other practical applications.

• Toxicological Research
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• v.12 no.2
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• pp.305-308
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• 1996

The acute toxicity of rHu-EPO, newly developed recombinant erythropoietin, was tested in beagle dogs. rHu-EPO, when administered intravenously at 25, 000 IU/kg, did not cause any death. Also, rHu-EPO did not induce any change of body weight, food intake and clinical signs compared to controls. There were no significant changes in hematological, urine analysis and pathological examination. These results showed that rHu-EPO did not induce any remarkable toxic response and the $LD_50$ was greater than 25, 000 IU/kg in beagle dogs.

• Imaging Science in Dentistry
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• v.39 no.3
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• pp.115-120
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• 2009

Purpose : The purpose of this study was to determine a conversion coefficient for Hounsfield Units(HU) to material density ($g\;cm^{-3}$) obtained from cone-beam computed tomography ($CBMercuRay^{TM}$) data and to measure the hard tissue density based on the Hounsfield scale on dental head phantom. Materials and Methods : CT Scanner Phantom (AAPM) equipped with CT Number Insert consists of five cylindrical pins of materials with different densities and teflon ring was scanned by using the $CBMercuRay^{TM}$ (Hitachi, Tokyo, Japan) volume scanner. The raw data were converted into DICOM format and the HU of different areas of CT number insert measured by using $CBWorks^{TM}$. Linear regression analysis and Student t-test were performed statistically. Results : There was no significant difference (P > 0.54) between real densities and measured densities. A linear regression was performed using the density, $\rho$($g\;cm^{-3}$), as the dependent variable in terms of the HU (H). The regression equation obtained was $\rho=0.00072H-0.01588$ with an $R^2$ value of 0.9968. Density values based on the Hounsfield scale was $1697.1{\pm}24.9\;HU$ in cortical bone, $526.5{\pm}44.4\;HU$ in trabecular bone, $2639.1{\pm}48.7\;HU$ in enamel, $1246.1{\pm}39.4\;HU$ in dentin of dental head phantom. Conclusion : CBCT provides an effective option for determination of material density expressed as Hounsfield Units.

• Imaging Science in Dentistry
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• v.38 no.1
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• pp.1-5
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• 2008

Purpose: The primary aims of this retrospective study were to compare subjective bone quality and bone quality based on the Hounsfield scale in different segments of the edentulous jaw, and to establish quantitative and objective assessment of the bone quality. Materials and Methods: Twenty eight randomly selected cone-beam computed tomographic (CBCT) scans were analyzed. For evaluation one hundred and twelve edentulous areas were selected. Implant recipient sites were evaluated visually for Lekholm and Zarb classification. The same sites were subsequently evaluated digitally using the Hounsfield scale with Vimplant$2.0^{TM}$, and the results were correlated with visual classification. Data was subject for statistical analysis in order to determine correlation between recorded HU and the regions of the mouth with the Kruskal-Wallis test. Results: The highest unit/mean density value (311 HU) was found in the anterior mandible, followed by 259 HU for the posterior mandible, 216 HU for the anterior maxilla, and 127 HU for the posterior maxilla. These results demonstrate a strong correlation for HU depending on the region of the mouth (p<0.001). The relationship between HU and type 4 bone was found to be significant (r=0.74). Conclusion: Knowledge of the Hounsfield value as a quantitative measurement of bone density can be helpful as a diagnostic tool by using $CBMercuRa6^{TM}$ with $Vimplant^{TM}$ software.

• Toxicological Research
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• v.3 no.1
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• pp.33-44
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• 1987

A fertility study was carried out in Sprague Daxley rats which have been given the intravenous or intraperitoneal injections of rHuIFN-${\alpha}$A, a commecially available therapeutic agent, at dose levels of $1{\times}10^5$, $4{\times}10^5$ and $1.2{\times}10^6$ I.U/kg/day. Male rats were treated with rHuIFN-${\alpha}$A from 60 days before pairing and until the completion of mating. Femal rats received rHuIFN-${\alpha}$A for 22days prior to mating and up to day of gestation. All pregnant females were sacrificed on day 20 of gestation and all fetuses were examined for abnormalities. Both the male and female animals treated with rHuIFN-${\alpha}$A did not show any abnormal responses. No abnormal signs were seen in reproducibility for the rats treated with rHuIFN-${\alpha}$A. No External, internal and skeletal anomalies attributable to rHuIFN-${\alpha}$A were observed in the fetuses. It was concluded that rHuIFN-${\alpha}A$ had no harmful effect on mating, fertilization, implantation, or embryonic development.