• Radiation Oncology Journal
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• v.16 no.3
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• pp.325-335
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• 1998

Purpose : Since the mid cranial fossa is composed of various thickness of bone, the tissue inhomogeneity caused by bone would produce dose attenuation in cobalt-60 gamma knife irradiation. The correction factor for bone attenuation of cobalt-60 which is used for gamma knife source is -3.5$\%$. More importantly, nearly all the radiosurgery treatment planning systems assume a treatment volume of unit density: any perturbation due to tissue inhomogeneity is neglected, This study was performed to confirm the bone attenuation in mid cranial fossa using gamma knife. Materials and Methods : Computed tomography was performed after Leksell stereotactic frame had been liked to the Alderson Rando Phantom (human phantom) skull area. Kodak X-omat V film was inserted into two sites of pituitary adenoma point and acoustic neurinoma point, and irradiated by gamma knife with 14mm and 18mm collimator. An automatic scanning densitometer with a 1mm aperture is used to measure the dose profile along the x and y axis. Results : Isodose curve constriction in mid cranial fossa is observed with various ranges. Pituitary tumor point is greater than acoustic neurinoma point (0.2-3.0 mm vs 0.1-1.3 mm) and generally 14 mm collimator is greater than 18mm collimator (0.4-3.0 mm vs. 0.2-2.2 mm) Even though the isodose constriction is found, constriction of 50$\%$ isodose curve which is used for treatment reference line does not exceed 1 mm. This range is too small to influence the treatment planning and treatment results. Conclusion : Radiosurgery planning system of gamma knife does not show significant error to be corrected without consideration of bone attenuation.

• Korean Journal of Poultry Science
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• v.48 no.3
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• pp.143-150
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• 2021

In this study, we investigated the effects of light intensity on broiler chick growth performance, blood parameters, and stress levels. A total of 240 one-day-old male Ross 308 broilers (47.97±0.166 g) were subjected to three different intensities of light (20, 30, and 50 lx), with each treatment being conducted with four replicates. On the seventh day, the growth performance (body weight, feed conversion ratio, and breast muscle and liver weights) and blood parameters were determined; the levels of serum corticosterone, interleukin-6 (IL-6), and tumor necrosis factor-α were also evaluated. The body weight, weight gain, liver weight, and breast muscle weight of chicks exposed to a light intensity of 50 lx were significantly increased compared with those of chicks subjected to 20 lx (P<0.05). No significant differences were observed in the leukocyte, erythrocyte, and platelet counts and the biochemical profile exceptions being the levels of glucose and inorganic phosphorus in the blood of the chicks in the three light intensity groups. However, serum corticosterone and IL-6 levels were the highest in chicks exposed to a light intensity of 20 lx (P<0.05). In conclusion, the findings of this study indicate that broiler chicks exposed to higher light intensity (50 lx) show significant improvements in terms of weight gain and corticosterone and IL-6 levels. Thus, high light intensities enhanced the growth performance, stress levels, and immune status of broiler chicks.

• BMB Reports
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• v.57 no.2
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• pp.110-115
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• 2024

Alterations in DNA methylation play an important pathophysiological role in the development and progression of colorectal cancer. We comprehensively profiled DNA methylation alterations in 165 Korean patients with colorectal cancer (CRC), and conducted an in-depth investigation of cancer-specific methylation patterns. Our analysis of the tumor samples revealed a significant presence of hypomethylated probes, primarily within the gene body regions; few hypermethylated sites were observed, which were mostly enriched in promoter-like and CpG island regions. The CpG Island Methylator Phenotype-High (CIMP-H) exhibited notable enrichment of microsatellite instability-high (MSI-H). Additionally, our findings indicated a significant correlation between methylation of the MLH1 gene and MSI-H status. Furthermore, we found that the CIMP-H had a higher tendency to affect the right-side of the colon tissues and was slightly more prevalent among older patients. Through our methylome profile analysis, we successfully verified the methylation patterns and clinical characteristics of Korean patients with CRC. This valuable dataset lays a strong foundation for exploring novel molecular insights and potential therapeutic targets for the treatment of CRC.