• The Korean Journal of Nuclear Medicine Technology
• /
• v.19 no.2
• /
• pp.68-73
• /
• 2015

Purpose The purpose of this study was to evaluate image quality change by truncated region in field of view (FOV) of attenuation correction computed tomography (AC-CT) in brain PET/CT. Materials and Methods Biograph Truepoint 40 with TrueV (Siemens) was used as a scanner. $^{68}Ge$ phantom scan was performed with and without applying brain holder using brain PET/CT protocol. PET attenuation correction factor (ACF) was evaluated according to existence of pallet in FOV of AC-CT. FBP, OSEM-3D and PSF methods were applied for PET reconstruction. Parameters of iteration 4, subsets 21 and gaussian 2 mm filter were applied for iterative reconstruction methods. Window level 2900, width 6000 and level 4, 200, width 1000 were set for visual evaluation of PET AC images. Vertical profiles of 5 slices and 20 slices summation images applied gaussian 5 mm filter were produced for evaluating integral uniformity. Results Patient pallet was not covered in FOV of AC-CT when without applying brain holder because of small size of FOV. It resulted in defect of ACF sinogram by truncated region in ACF evaluation. When without applying brain holder, defect was appeared in lower part of transverse image on condition of window level 4200, width 1000 in PET AC image evaluation. With and without applying brain holder, integral uniformities of 5 slices and 20 slices summation images were 7.2%, 6.7% and 11.7%, 6.7%. Conclusion Truncated region by small FOV results in count defect in occipital lobe of brain in clinical or research studies. It is necessary to understand effect of truncated region and apply appropriate accessory for brain PET/CT.

• Childhood Kidney Diseases
• /
• v.8 no.2
• /
• pp.138-148
• /
• 2004

Purpose: Regardless of the underlying diseases, the proteinuric condition demonstrates ultrastructural changes in podocytes with retraction and effacement of the highly specialized interdigitating foot processes. We examined the molecular basis for this alteration of the podocyte phenotypes, including quantitative and distributional changes of ZO-1 protein as a candidate contributing to the pathogenic changes in the barrier to protein filtration. Methods: To investigate whether high glucose and advanced glycosylation endproduct(AGE) induce podocyte cytoskeletal changes, we cultured rat GEpC under 1) normal glucose(5 mM=control) or 2) high glucose(30 mM) or 3) AGE-added or 4) high glucose plus AGE-added conditions. The distribution of ZO-1 was observed by confocal microscope and the change of ZO-1 expression was measured by Western blotting and RT-PCR. Results: By confocal microscopy, we observed that ZO-1 moves from peripheral cytoplasm to inner actin filaments complexes in both AGE-added and high glucose condition. In Western blotting, high glucose or AGE-added condition decreased the ZO-1 protein expression by 11.1%(P>0.05) and 2.3%(P>0.05), respectively compared to the normal glucose condition. High glucose plus AGE-added condition further decreased ZO-1 protein expression to statistically significant level(12%, P<0.05). No significant change was seen in the osmotic control. In RT-PCR, high glucose plus AGE-added condition significantly decreased the expression of ZO-1 mRNA by 12% compared to normal glucose condition. Conclusion: We suggest that both high glucose and AGE-added condition induce the cytoplasmic translocation and suppresses the production of ZO-1 at transcriptional level and these changes may explain the functional changes of podocytes in diabetic conditions.

• The korean journal of orthodontics
• /
• v.31 no.6 s.89
• /
• pp.589-600
• /
• 2001

Insulin-like growth factor I (IGF-I) has the local tissue regulating actions. In bone, IGF-I increases the replication of osteoblastic lineage, probably preosteoblasts, and enhances osteoblastic collagen synthesis and matrix composition rates. The purpose of this study was to investigate the local regulatory effect of IGF-I on periodontium totally, both in an autocrine and paracrine manner. To examine the effect of IGF-I directly on osteoblast (OB) of test rats, and indirectlv on OB via periodontal ligament fibroblast (PDLF), and the effect of gingival fibroblast (GF) on OB via cellular paracrine manner for the understanding of humoral action of adjacent tissue, GF and PDLF were obtained from male Sprague-Dawley rats of six to eight weeks of age. OB was obtained iron frontal and parietal calvarial bone of Sprague-Dawley 21day-old-fetus. After each tell was Incubated 24 hours, for collecting conditioned medium, different concentrations of IGF-I (1,10,100 ng/ml,1ml/well) was adding in the GF, PDLF cells, and the supernatant from these cultures was put into the primary OB culture with $1{\times}10^4$cell/ml/well. The experimental group was divided into six groups control OB, IGF-I treated OB, OB culture with conditioned medium from PDLF, OB culture with conditioned medium from IGF-I treated PDLF, OB culture with conditioned medium from GF, OB culture with conditioned medium from IGF-I treated GF. After final IGF-I treatment, OB was Incubated for 24 hours, and alkaline phosphatase activity assay, BMP expression, cell proliferation measurement using MTT assay, total protein measurement, Collagen synthesis assay using western blot, and examination of bone nodule synthesis were done. Alkaline phosphatase expressions were increased in the group of PDLF-IGF-I supernatant treatment. Direct IGF-I treatment with concentrations of 100ng/m1 showed increased viable tell number measured by MTT assay. And IGF-I treatment did not increase total protein amount. The entire experimental group showed BMP2, 4 expression in western blot, and there was no significant difference between control and experimental groups. These results suggested that supernatant from PDLF effects on increasing cellular activities of OB regardless of IGF-I, and at high concentration, IGF-I increases OB tell proliferation.

• Parasites, Hosts and Diseases
• /
• v.27 no.2
• /
• pp.109-118
• /
• 1989

Production of circulating specific antibodies to the lung fluke (Paragenimus westermani) by its host is well known and used in various kinds of immunodiagnostic methods, However, it has not been well documented which compartments (or structures) of the lung fluke are most responsible for the production of specific antibodies. The present immunohistochemical study was undertaken to demonstrate the antigenicity of each body compartment of p. westermani such as suckers, tegument, spines, vitelline glands, intestine, reproductive organs(male and female), and eggs. Indiret immunoperoxidase(IP) stain technique was applied, using formalin-fked, paraffin- embedded lung tissues of P westermani-infected cats sectioned in 4 Um thickness as the antigen and cat antisera (11~20 weeks of infection) as the primary antibody. Peroxidase-conjugated goat anti-cat IgG was used as the secondary antibody and diaminobensidine(DAB) as the coloring agent. Strong yellow or yellowish brown staining was regarded positive. The primary and secondary antibody dilutions were made at 1 : 500~1 : 2, 000 and 1 : 200~1 : 500 respectively, and IP stain was repeated 10 times for each dilution. A consistent result obtained was that the intestinal epithelial border, intestinal content, vitelline glands, and eggs scattered around the worm capsule showed strong positive staining, while uterine eggs and some parenchymal portions showed weak positive reaction. On the other hand, the suckers, tegument, spines, subtegumental cells, cytoplasm of intestinal epithelial cells, male reproductive organs, and ovary revealed negative staining. The body compartments showing higher antigenicity were, in the decreasing order, the intestinal epithelial border, intestinal content, eggs in the worm capsule, vitelline glands, uterine eggs, and parenchymatous portions. The intestinal epithelial border and luminal contents revealed positive staining even at a few concentration of 1 : 4, 000 primary antibody(secondary ab., 1 : 200) whereas the parenchymatous portion showed positive reaction only at higher concentrations than 1'500 (secondary ab., 1 : 200). The results suggest that the specific antibody responses of the host to p. westermani occur most strongly upon the excretes from the intestinal epithelium of the worm and e99s Produced around the worm capsule,

• Korean Journal of Soil Science and Fertilizer
• /
• v.10 no.3
• /
• pp.135-151
• /
• 1977

The present paper summerizes the studies on clay mineralogical characteristics of Korean soil, relationship between potassium and clay minerals, potassium release pattern of clay minerals and utilization of clay minerals for soil conditioner and fertilizers, which have been carried out in this laboratory. 1. The red yellow podzolic soil is mostly abundant in the upland of Korea and mainly consists of halloysite and weathered intermediates of mica such as illite and vermiculite. 2. With regard to soil parent material, kaolin mineral occurs abundant in soils derived from granite and granite gneiss. Mica is dominant in basaltic soil. The main clay mineral of the soil, originated from the Tertiary, is found montmorillonite and the volcanic soil of Jeju Island has plenty of allophane as its main clay mineral. 3. It is confirmed that the soil fertility depends on the composition of clay minerals. The red yellow podzolic soil, containing lot of kaolin, shows low productivity while the montmorillonite soil has higher productivity. 4. The release rate of solid phase potassium (micas and fixed potassium) follows the 1st order reaction equation in the equilibrium solution of $IN-NH_4OAc$. The potassium release constant is positively correlated with the mica content of the clay but negatively correlated with the content of $14.5{\AA}$ minerals. On the other hand, the potassium release constant has very high correlation with the ratio(Kex/Kt) of exchangeable potassium(Kex) to total potassium(Kt). 5. It is also found that Kex/Kt has rather high correlation with the content of mica and $14.5{\AA}$ minerals existed in the clay as well as the mica content of the soil.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.6
• /
• pp.904-909
• /
• 2012

Acid sulfate soil (ASS) and potential acid sulfate soil (PASS) are distribution in worldwide and originate from sedimentary process, volcanic activity, or metamorphism and are problematic in agriculture and environmental due to their present and potential acidity developed by the oxidation. The PASS was defined as soil materials that had sulfidic layer more than 20 cm thick within 4 m of the soil profile and contained more than 0.15% of total-sulfur (T-S). A tentative interpretative soil classification system was proposed weak potential acid sulfate (T-S, 0.15-0.5%), moderate potential acid sulfate (T-S, 0.5-0.75%) and strong potential acid sulfate (T-S, more than 0.75%). PASS due to excess of pyrite over soil neutralizing capacity are formed. It provides no information on the kinetic rates of acid generation or neutralization; therefore, the test procedures used in acid base account (ABA) are referred to as static procedures. The net acid generation (NAG) test is a direct method to measure the ability of the sample to produce acid through sulfide oxidation and also provides and indication. The NAG test can evaluated easily whether the soils is PASS. The samples are mixed sandy loam and the PAS from the hydrothermal altered andesite (1:3, 1:8, 1:16, 1:20, 1:40, 1:80 and 1:200 ratios) in this study. We could find out that the NAG pH of the soil containing 0.75% of T-S was 2.5, and that of the soil has 0.15% of T-S was 3.8. NAG pH test can be proposed as soil classification criteria for the potential acid sulfate soils. The strong type has NAG pH of 2.5, the moderate one has NAG pH of 3.0, and the weak one has NAG pH of 3.5.

• Journal of Korean Society of Transportation
• /
• v.23 no.7 s.85
• /
• pp.165-179
• /
• 2005

The object of this study is a development of a stochastic user equilibrium transit assignment algorithm for multiple user classes considering stochastic characteristics and heterogeneous attributes of passengers. The existing transit assignment algorithms have limits to attain realistic results because they assume a characteristic of passengers to be equal. Although one group with transit information and the other group without it have different trip patterns, the past studies could not explain the differences. For overcoming the problems, we use following methods. First, we apply a stochastic transit assignment model to obtain the difference of the perceived travel cost between passengers and apply a multiple user class assignment model to obtain the heterogeneous qualify of groups to get realistic results. Second, we assume that person trips have influence on the travel cost function in the development of model. Third, we use a C-logit model for solving IIA(independence of irrelevant alternatives) problems. According to repetition assigned trips and equivalent path cost have difference by each group and each path. The result comes close to stochastic user equilibrium and converging speed is very fast. The algorithm of this study is expected to make good use of evaluation tools in the transit policies by applying heterogeneous attributes and OD data.

• Environmental Analysis Health and Toxicology
• /
• v.15 no.4
• /
• pp.131-137
• /
• 2000

The release of hazardous waste materials into the environment poses serious risks in humans and ecosystems. The risk assessment of environmental pollutants including hazardous chemicals requires a comprehensive measurement of hazard and exposure of the chemicals that can be achieved by toxicity evaluation using a biological system such as biomarkers. In this report we have tried to develop a biomarker used to elucidate a molecular basis of, and to monitor abnormal behaviors caused by diazinon in Japanese medaka (Oryzias latipes) as a model organism. First, an attempt was made to clone tyrosine hydroxylase gene from Japanese medaka that would be a candidate for a biomarker for neuronal modulations and behaviors. For monitoring experiments at behavioral and molecular biological levels, the fish were treated under different sublethal conditions of diazinon and their behavioral responses were observed . In this study we have successfully cloned a partial TH gene from the medaka fish through PCR screening of an ovary cDNA library. DNA sequencing analysis revealed that the amplified fragment was 327 bp encoding 109 amino acids. Comparing the DNA sequence of medaka TH with other species, TH gene revealed the DNA sequence was completely identical to that of rat TH. In the RT-PCR, 330 Up of mRNA was consistently amplified in all the treated samples including control There were no significant differences in the TH expression level regardless of treating concentrations (1∼5,000 ppb) and time (0∼48 hr) The reason appeared to be that RT-PCR was not performed using through a quantitative analysis normalized against an actin gene expression. Organ or tissue - specific detection of TH activity and mRNA as biomarkers will be a useful monitoring tool for neurobehavioral changes in fish influenced by toxic chemicals. Furthermore, quantitative analysis of locomotive patterns and its correlation with the neurochemical and molecular data would be highly useful in measuring toxicity and hazard ofvarious environmental pollutants.

• Journal of Applied Biological Chemistry
• /
• v.61 no.2
• /
• pp.205-211
• /
• 2018

Rebaudioside A is a natural sweetener isolated from Stevia rebaudiana Bertoni, one of the glycosides based on steviol. Recent studies have shown that rebaudioside A inhibits the inflammatory response by inhibiting cytokines secretion such as interleukin-$1{\alpha}/1{\beta}$ in activated RAW264.7 mouse macrophage cells by LPS. However, the inhibitory mechanism of inflammation by rebaudioside A in the presence of LPS has not been fully elucidated. Therefore, in this study, we tried to investigate the anti-inflammatory activity of rebaudioside A at the protein level when RAW264.7 cells were stimulated by LPS. The inducible nitric oxide synthase protein expression level was reduced in the group treated with $250{\mu}M$ rebaudioside A compared to the LPS-treated group. In addition, the mRNA expression level of $NF-{\kappa}B$, which is a representative nuclear transcription factor by inflammatory signal, was also decreased as compared with that of LPS-treated group. In addition, $NF-{\kappa}B$ and inhibitor-${\kappa}B$ ($I-{\kappa}B$) complexes that are known to be dissociated by $I-{\kappa}B$ phosphorylation and ubiquitination were less phosphorylated than LPS treated group in the presence rebaudioside A. Finally, we could find that rebaudioside A was involved in the $NF-{\kappa}B$ pathway through reducing extracellular signal-regulated kinase1/2 phosphorylation in a concentration-dependent manner. These results suggest that rebaudioside A might suppress inflammatory reaction through MAPK and $NF-{\kappa}B$ regulation in LPS-stimulated RAW264.7.

• Journal of Conservation Science
• /
• v.23
• /
• pp.25-37
• /
• 2008

This study focuses on identification of mineralogical and geochemical characteristics and interpretation of raw material sources for prehistoric chlorite beads excavated from Geoseokri site in Boseong and Buntori site in Haenam, Korea. These prehistoric beads consist of three grayish blue ring-shaped beads, one dark green tubular bead and one greenish black tubular bead that show acicular-columnar and fibrous microtexture. The beads are composed of $SiO_2$, $Al_2O_3$, MgO and FeO as majors and a trace amount of $K_2O$, CaO and Na_2O$. Mineral species is mostly chlorite with a small amount of quartz and feldspar. Quantitative analysis indicates that the grayish blue ring-shaped beads and the dark green tubular bead belong to clinochlore and the greenish black tubular bead does to the boundary between clinochlore and sheridantie. Chlorite is a hydrous phyllosilicate mineral and it shows various microtexture of acicular, sheeted, earthy, granular andfibrous shapes. As its hardness is 2, chlorite is easily engraved due to its softness. It has aesthetic worthy as it shows green, black and greenish gray colors and pearly to greasy luster as well. These factors would lead to the extensive use of chloritic beads as ornaments from prehistoric times. Though the mineral sources of the chlorite beads can be found in central western region of Chungnam and Iwon of Hamnam, those areas are too distant from the two relic sites. Instead, chlorite ores commonly occur as altered products in wall rock alteration zone of every hydrothermal deposit. Therefore, it is probable that raw materials of chlorite were supplied from neighboring hydrothermal environment rather than far deposits. The result needs further study to verify raw material provenance interpretation, supply, manufacture and distribution on the basis of archaeological points of view.