• The Korean Journal of Nuclear Medicine
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• v.38 no.3
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• pp.253-258
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• 2004

Purpose: Chitosan has been studied as a non-viral gene delivery vector, drug delivery carrier, metal chelator, food additive, and radiopharmaceutical, among other things. Recently, galactose-graft chitosan was studied as a non-viral gene and drug delivery vector to target hepatocytes. The aim of this study was to investigate the usefulness of nuclear imaging for in vivo evaluation of targeting the hepatocyte by galactose grafting. Methods and Materials: Galactosyl methylated chitosan (GMC) was produced by methylation to lactobionic acid coupled chitosan. Cytotoxicity of $^{99m}Tc$-GMC was determined by MTT assay. Rabbits were injected via their auricular vein with $^{99m}Tc$-GMC and $^{99m}Tc$-methylated chitosan (MC), the latter of which does not contain a galactose group, and images were acquired with a gamma camera equipped with a parallel hole collimator. The composition of the galactose group in galactosylated chitosan (GC), as well as the tri-, di-, or mono-methylation of GMC, was confirmed by NMR spectroscopy. Results: The results of MTT assay indicated that $^{99m}Tc$-GMC was non-toxic. $^{99m}Tc$-GMC specifically accumulated in the liver within 10 minutes of injection and maintained high hepatic uptake. In contrast, $^{99m}Tc$-MC showed faint liver uptake. $^{99m}Tc$-GMC scintigraphy of rabbits showed that the galactose ligand principally targeted the liver while the chitosan functionalities led to excretion through the urinary system. Conclusion: Bioconjugation with a specific ligand endows some degree of targetability to an administered molecule or drug, as in the case of galactose for hepatocyte in vivo, and evaluating said targetabililty is a clear example of the great benefit proffered by nuclear imaging.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.83-94
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• 2003

Concentrated releases of zinc into water usually results from discharges associated with industrial purpose. The released zinc into soil is corroded and released into water. In aquatic environment, exess zinc is toxic to the organisms and causes the growth inhibition and malformation of them as a heavy metal. In this study, excess zinc toxicity was tested by FETAX (frog embryo teratogenetic assay with Xenopus)as in vivo system. Xenopus embryos at st.9 were exposed to $100{\sim}900\;{\mu}M$ of zinc for 7 days and 81% of individuals were survived in 100 ${\mu}M$, and 25% were survived in 1000M of zinc solution. In external malformations, swelled belly and intestinal dysplasia were common, and all of tested individuals showed these malformations in 200 ${\mu}M$ or higher concentration of zinc. In 400 ${\mu}M$ or higher concentration, all of tested tadpoles showed faded heart. Also, hypo-pigmentation, lens hernia and loose digestive track were very frequently found in 100 ${\mu}M$ of zinc. The histological study with paraffin section of zinc treated tadpoles showed following abnormalities; regeneration of photoreceptor on retina, reduced vitreous chamber in eye, reduction of red blood cells in heart, abnormal liver, swelling of pronephric cell, muscle dysplasia and palatal papilloma. These abnormalities may be caused by the degeneration of mitochondria, inhibition of cell adhesion, and the formation of leghemoglobin by zinc due to the substitution of $Ca^{2+}$ by $Zn^{2+}$. The body length was reduced due to the excess zinc. From a statistical result, body lengths of 300 ${\mu}M$ or higher concentrative g개ups was significantly reduced comparing that of control group. Recently, many spontaneous malformations and reduction of amphibians are reported, From the results of present study, excess zinc mi호t be a factor of amphibian reduction, and the control of zinc discharges is very important.

• Journal of Life Science
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• v.22 no.1
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• pp.41-48
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• 2012

Bee venom (BV) has been used in medicine to treat a variety of diseases including arthritis, rheumatism, and various cancers. Recent reports indicate that BV has anti-angiogenic effects, but the precise molecular mechanism underlying the effects of BV against colorectal cancer remains to be elucidated. We examined the effects of BV and its major components (melittin and apamin) on tumor angiogenesis and found that BV significantly decreased protein levels of hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$), an important factor involved in angiogenesis and tumor progression, in human colorectal carcinoma HCT116 cells. BV also suppressed the transcription of HIF-$1{\alpha}$ under hypoxia, leading to a decrease in the expression of vascular endothelial growth factor (VEGF), a major target gene of HIF-$1{\alpha}$. We also found that these effects were mainly elicited by apamin, but not melittin. BV specifically inhibited the phosphorylation of ERK1/2 without changing the total levels of this protein, but had no effect on kinases of p38/JNK and AKT. Our results suggest that BV may inhibit human colorectal cancer progression and angiogenesis by inhibiting HIF-$1{\alpha}$ and VEGF expression, thereby providing a novel potential mechanism for the anticancer action of BV.

• Journal of the Korean Chemical Society
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• v.17 no.3
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• pp.145-153
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• 1973

The temperature effects on the equilibria between polymolybdatd anions in 1M sodium perchlorate solution has been investigated in the temperature range of 20~50$^{\circ}$C. The polymolybdate anions formed are heptamolybdate ($Mo_7O_{24}^{6-}$) ions and the protonized forms of heptamolybdate ions ($H_LMo_7O_{24}^{(6-L)-}$). The equilibrium constants for the formation of heptamolybdate ions calculated by Sillen's method are as follow;$8H^{+}+7MoO_4^{2-}=Mo_7O_{24}^{6-}+4H_2O$, $k_{7.8}=2.77{\times}10^{53}:20^{\circ}C= 9.29{\times}10^{51}:40^{\circ}C$,$k_{7.8}= 4.22{\times}10^{52}:30^{\circ}C = 9.29{\times}10^{51}:50^{\circ}C$ The enthalpy change for calculated for the above reaction is 31.51 kcal/mole. A method of calculation of the equilibrium constants for the formation of protonized heptamolybdate ions from heptamolybdate ions and hydrogen ions has been derived. The equilibrium constants calculated for the formation of protonized heptamolybdate ions are as follow; $ LH^++ Mo_7O_{24}^{-6} = H_LMo_7O_{24}^{(6-L)-} : L = 1\;or\;2$, $k_1 = 2.31{\times}10^4=2.53{\times}10^4=2.76{\times}10^4= 3.10{\times}10^4$, $k_2 = 6.19{\times}10^7\;20^{\circ}C = 7.80{\times}10^7\;30^{\circ}C = 1.22{\times}10^8\;40^{\circ}C = 2.03{\times}10^8\;50^{\circ}C$The enthalpy change for the following step reactions are as follow;$H^{+}+Mo_7O_{24}^{6-}= HMo_7O_{24}^{5-}\;{\Delta}H^{\circ}=1.90 kcal/mole$, $2H^{+}+Mo_7O_{24}^{6-}=H_2Mo_7O_{24}^{4-}\;{\Delta}H^{\circ}=7.50kcal/mole$

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.460-472
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• 1995

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by difference in seeding date. Yield and yield contribution rates of tillers were investigated with the data of field experiments in the former Wheat and Barley Research Institute of Suwon, Korea from September 1982 to July 1984. When barley was sowed 15 days earlier than or at the locally recommended sowing date (i.e. October 5), it produced more mainstem leaves than the that sowed 15 days later than the local recommendation. The effective tillers (i.e. ear-bearing tillers) were observed in concurrently occurring leaves up to 10/0 (abbreviation of the 10th mainstem leaf) from early and optimum sowed crops, while 9/0 from late sowed crops. Tillering followed the production rule of Gatayama(l952) which has the linear leaf appearance pattern. Early sowing produced more effective tillers, but the highest production of effective ears (i.e. ears heavier than 0.505g) was noticed in sowing at the recommended date. The tillers in the axil of first leaf in mainstem (abbreviated as 1) produced more effective ears than other mainstem tillers (i.e. primary tillers such as C, 2, 3 and 4). The tillers from the axil of first leaf, whether they were primary or secondary, always performed better in the production of effective tillers, grains per ear, grain weight, and grain yield per ear than those from the axil of coleoptile or prophyll. Other tillers from subsequent leaves were also inferior in production with the order of their appearance, thus making first leaf tillers as the best performer(e.g. 1 against C, 2, 3, 4 of primary tillers, 11 and 21 against 1P, 12, 13, 2P, 22 of secondary tillers). Even though the first leaf tiller from the first mainstem leaf(i.e. 11) emerged at a same time with the fourth mainstem leaf tiller(i.e. 4), it was always a better producer of ears and grains. The above observations of hierarchy among tillers were persistent irrespective of cropping conditions and treatments. Sowing at the recommended date produced more effective tillers and grains per ear than early or late sowing. In early and late sowings, more grains per effective ear were observed by early sowing, whereas more grains per ear were produced by late sowing. The order of performance in production of effective tillers and ears per plant was as follows: optimum > early > late sowings. In optimum sowing the mainstems were the highest in grain weight per ear, while the first leaf tillers were the ones in early sowing probably due to winter damage on mainstem ears. Yield contribution by the tillers was greater with the following order irrespective of sowing dates: mainstem, 1, 2, 3, C, 11, 12 and Cl. The contribution of CP, 2P, 21 and 31 varied with sowings.

• Economic and Environmental Geology
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• v.39 no.1 s.176
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• pp.9-25
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• 2006

Baekun gold-silver deposit is an epithermal quartz vein that is filling the fault zone within Triassic or Jurassic foliated granodiorite. Mineralization is associated with fault-breccia zones and can be divided into two stages. Stage I which can be subdivided early and late depositional stages is main ore mineralization and stage II is barren. Early stage I is associated with wallrock alteration and the formation of sulfides such as arsenopyrite, pyrite, pyrrhotite, sphalerite, marcasite, chalcopyrite, stannite, galena. Late stage I is characterized by Au-Ag mineralization such as electrum, Ag-bearing tetrahedrite, stephanite, boulangerite, pyrargrite, argentite, schirmerite, native silver, Ag-Te-Sn-S system, Ag-Cu-S system, pyrite, chalcopyrite and galena. Fluid inclusion data indicate that homogenization temperatures and salinity of stage I range from $171.6^{\circ}C\;to\;360.8^{\circ}C\;and\;from\;0.5\;to\;10.2\;wt.\%\;eq.$ NaCl, respectively. It suggest that ore forming fluids were cooled and diluted with the mixing of meteoric water. Also, Temperature (early stage I: $236\~>380^{\circ}C,\;$ late stage $I: <197\~272^{\circ}C$) and sulfur fugacity (early stage $I:\;10^{-7.8}$ a atm., late stage I: $10^{-14.2}\~10^{-l6}atm$.) deduced mineral assemblages from stage 1 decrease with paragenetic sequence. Sulfur ($2.4\~6.1\%_{\circ}$(early stage $I=3.4\~5.3\%_{\circ},\;late\;stage\;I=2.4\~6.1\%_{\circ}$)), oxygen ($4.5\~8.8\%_{\circ}$(quartz: early stage $I=6.3\~8.8\%_{\circ}$, late stage $I=4.5\~5.6\%_{\circ}$)), hydrogen ($-96\~-70\%_{\circ}$ (quartz: early stage $I=-96\~-70\%_{\circ},\;late\;stage\;f=-78\~-74\%_{\circ},\;calcite:\;late\;stage\;I=-87\~-76\%_{\circ}$)) and carbon ($-6.8\~-4.6\%_{\circ}$ (calcite: late stage I)) isotope compositions indicated that hydrothermal fluids may be magmaticorigin with some degree of mixing of another meteoric water for paragenetic time.

• Economic and Environmental Geology
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• v.32 no.5
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• pp.435-444
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• 1999

The antimony deposits of the Hyundong mine, located in the northeastern part of the Sobaegsan massif, occur as hydrothermal quartz+carbonate veins and stockworks which fill the fault fractures developed in Precambrian metamOlphic rocks (mainly, granitic gneiss). Hydrothermal alteration occurs commonly in the vicinity of mineralized veins and is characterized by sericitization and silicification. A K-Ar age of alteration sericite is 139.2$\pm$ 4.4 Ma, implying the early Cretaceous age of mineralization, possibly in association with intrusion of nearby acidic dikes (mainly, quartz porphyry). The hydrothermal mineralization occurred in five mineralization stages. These are: (I) stage I, characterized by deposition of chalcedonic quartz; (2) stage II, deposition of quartz with base-metal sulfides and stibnite; (3) stage III, deposition of quartz and carbonates (calcite, dolomite, ankerite, rhodochrosite) with various antimony-bearing minerals such as stibnite, polybasite, berthierite, native antimony, gudmundite and ullmannite; (4) stage IV, deposition of calcite with stibnite; and (5) stage V, deposition of barren calcite. Antimony occurs mostly as stibnite within stages II to IV veins, which has various habits including disseminated, veinlets and euhedral coarse crystals. Fluid inclusion studies indicate that hydrothermal mineralization at Hyundong occurred from the fluids with temperature and salinity of $330^{\circ}$C to 120 and 5.3 wI. % equiv. NaCI. The temperature and salinity of ore fluids systematically decreased with elapsed time in the course of mineralization, possibly due to the influx of larger amounts of meteoric groundwater. The deposition of antimony-bearing minerals occurred at low temperatures «$250^{\circ}$C), mainly due to the cooling and dilution of fluids. Based on the evidence of fluid boiling during the early stage II mineralization, the mineralization occurred under low pressure conditions (about 80 bars, corresponding to depths of about 350 m under hydrostatic pressure regime). Thermodynamic considerations of ore . mineral assemblages indicate that antimony deposition also occurred as the results of decreases in temperature and sulfur fugacity of hydrothermal fluids. Calculated sulfur isotope composition of ore fluids ($\delta^{34}S_{\Sigma s}$=5.4 to 7.8$\textperthousand$) indicates an igneous source of sulfur.

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.91-97
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• 2007

To evaluate the physiological status of laying flocks, the blood chemistry values were measured and analyzed in various ages under different feeding conditions. Total 671 birds from 48 Hyline brown hens flocks from 13 different poultry farms were bled at the ages of day(s) 1, 11, 21, 50, 80, 120, 180, 240, 300, 400, and 500. The 17 blood chemistries including glucose, lipids, proteins, enzymes, electrolytes and metabolic by-products were measured with an autoanalyzer. Blood glucose showed the highest at the hatching day not relate with the dietary carbohydrates and energy, but tended to decrease during the rest of growth stage in hens. Total blood protein, albumin and globulin increased depending on the ages even though dietary protein was decreased. Blood lipid was greatly changed at different growth stages. Cholesterol was the highest at hatching period and maintained consistently until the 120 days of age. It was increased in birds after 180 days of age. HDL was also highest in hatchery, but decreased greatly after 180 days of age. However, TG was the lowest at one day old, but was increased up to 10 times after 180 days of age compared to that of one day old. The enzyme activities were different. AST, ALT, and GGT showed comparatively contained consistently, whereas amylase was slowly decreased. Blood P, Na, K and Cl showed consistency, but Ca content was increased upto two times of the one day of age. The results from this study showed that the blood chemistry values were affected by the general metabolic status of the host with ages not by feeding conditions. Further, the standard data of age-dependent blood chemistry values in the laying flocks were obtained, which can be utilized for early detection of the changes in the physiological status occurred by the infectious or metabolic diseases. The results of these analyses seemed to be useful to increase the productivity of laying flocks through rapid and proper veterinary medical treatments.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.119-120
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• 2004

Urban groundwater has a unique hydrologic system because of the complex surface and subsurface infrastructures such as deep foundation of many high buildings, subway systems, and sewers and public water supply systems. It generally has been considered that increased surface impermeability reduces the amount of groundwater recharge. On the other hand, leaks from sewers and public water supply systems may generate the large amounts of recharges. All of these urban facilities also may change the groundwater quality by the recharge of a myriad of contaminants. This study was performed to determine the factors controlling the recharge of deep groundwater in an urban area, based on the hydrogeochemical characteristics. The term ‘contamination’ in this study means any kind of inflow of shallow groundwater regardless of clean or contaminated. For this study, urban groundwater samples were collected from a total of 310 preexisting wells with the depth over 100 m. Random sampling method was used to select the wells for this study. Major cations together with Si, Al, Fe, Pb, Hg and Mn were analyzed by ICP-AES, and Cl, N $O_3$, N $H_4$, F, Br, S $O_4$and P $O_4$ were analyzed by IC. There are two groups of groundwater, based on hydrochemical characteristics. The first group is distributed broadly from Ca-HC $O_3$ type to Ca-C1+N $O_3$ type; the other group is the Na+K-HC $O_3$ type. The latter group is considered to represent the baseline quality of deep groundwater in the study area. Using the major ions data for the Na+K-HC $O_3$ type water, we evaluated the extent of groundwater contamination, assuming that if subtract the baseline composition from acquired data for a specific water, the remaining concentrations may indicate the degree of contamination. The remainder of each solute for each sample was simply averaged. The results showed that both Ca and HC $O_3$ represent the typical solutes which are quite enriched in urban groundwater. In particular, the P$CO_2$ values calculated using PHREEQC (version 2.8) showed a correlation with the concentrations of maior inorganic components (Na, Mg, Ca, N $O_3$, S $O_4$, etc.). The p$CO_2$ values for the first group waters widely ranged between about 10$^{-3.0}$ atm to 10$^{-1.0}$ atm and differed from those of the background water samples belonging to the Na+K-HC $O_3$ type (<10$^{-3.5}$ atm). Considering that the p$CO_2$ of soil water (near 10$^{-1.5}$ atm), this indicates that inflow of shallow water is very significant in deep groundwaters in the study area. Furthermore, the P$CO_2$ values can be used as an effective parameter to estimate the relative recharge of shallow water and thus the contamination susceptibility. The results of our present study suggest that down to considerable depth, urban groundwater in crystalline aquifer may be considerably affected by the recharge of shallow water (and pollutants) from an adjacent area. We also suggest that for such evaluation, careful examination of systematically collected hydrochemical data is requisite as an effective tool, in addition to hydrologic and hydrogeologic interpretation.ion.ion.

• Journal of Sericultural and Entomological Science
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• v.23 no.2
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• pp.37-49
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• 1982

Larvae of the silkworm (Bombyx mori L.) were reared during the 5th instar on the four kinds of artificial diets on the basis of the different amounts of soybean meal used as the protein source. In this experiment it was shown that the various levels of protein in the diet affected not only the growth and silk production but the digestibility of the diet. haemolymph protein and uric acid excretion. The results obtained are summarized as follows; 1. By an increase of the level of protein in the diet the apparant digestibility was increased. but the protein digestibility was comparatively decreased. 2. Larval body weight increment was not observed by the 3rd day of the 5th instar, but was increased from the 4th day as the level of protein was increased in the diet. 3. After the 3rd day of the 5th instar, protein content in the hemolymph was increased steeply by an increase of the protein content in the diet. However, the percentage of hemolymph protein to the ingested protein was decreased from the 2nd day of the 5th instar and increased more or less after the 4th day. 4. An increase of the uric acid excretion was observed as the content of protein in the diet was increased but the pattern of the uric acid excretion was different between high and low-protein diet. However, the percentage of the uric acid excretion to the ingested protein and to the hemolymph protein were both decreased steeply after the 2nd day of the 5th instar. 5. It was also evident that the high-protein diet increased the cocoon productivity. 6. It showed that the feed efficiency for body weight increment and silk formation was high by an increase of the level of protein in the diet, but the protein efficiency was not.