• Journal of the Korean Chemical Society
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• v.32 no.4
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• pp.342-350
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• 1988

An experimental investigation is made to determine the mechanism of the aquation of $[Co(en)_2Cl_2]^+$ in $Hg^{2+}$ aqueous solution. The progress of reaction is followed UV/vis-spectrophotometrically by a measurment of the absorbance at a specific wavelength of Co(III) complex as a function of time. The aquation of cis-$[Co(en)_2Cl_2]^+$ and trans-$[Co(en)_2Cl_2]^+$ has been found to be first order and second order with respect to the concentration of $Hg^{2+}$ catalyst, respectively. It has been found that the reaction rate for aquation of the trans-form is faster than that of cis-form, and that the product of either cis-form or trans-form is always in the mixture ratio of 97 % to 3 %. Plausible reaction mechanism is proposed for the reaction system on the basis of kinetic data and activation parameters. Theoretical rate equation derived from the proposed mechanism is consistent with the observed one.

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.245-250
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• 1984

Reciprocal exchanges of DNA in sister chromatids (SCEs) are induced by various carcinogens and mutagens, although the quantitative relationship between the number of mutations and SCEs induced varies among chemicals. Nevertheless, the analysis of SCEs production by various agents often proposed as a sensitive and quantitative assay for mutagenicity and cytotoxicity. Mercury, even if which has no evidences for mutagenicity and carcinogenicity, is reported to exert some cytotoxic effects, such as chromosomal aberrations or bad influences to ovulation and reproduction in experimental animals, etc.. In this study, tests for sister chromatid exchanges have been carried out on normal human lymphocytes in whole blood culture to add mercury chloride ($HgCl_2$) or methylmercury chloride ($CH_3\;HgCl$) for 72 hr. The results indicate the dose-dependent relationship between the frequencies of SCEs and the concentrations of $HgCl_2,\;CH_{3}HgCl$ and 5-bromo-2'-deoxyuridine (BrdU). Lymphocyte proliferation has depressed in the higher concentration of mercury.

• Applied Microscopy
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• v.31 no.2
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• pp.175-184
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• 2001

This study aims demonstrate the effect of chitosan, one of the natural chelator, on the ultrastructural changes in the mouse liver caused by $HgCl_2$. The experimental group was divided in two groups; group A and group B. The group A administrated $HgCl_2$ (5.0 mg/kg) to the oral. The group B treated with $HgCl_2$ (5.0 mg/kg) and chitosan (3%) solution, 2 times/day). Each group was observed 24, 48, 72 and 96 hours after treated $HgCl_2$ and chitosan. Histological changes of the livers were investigated by electron microscope. 1. Croup A Nuclear membrane was shrinked. The inner and outer membrane of the mitochondria were dilated. Destruction of lamellae of rough endoplasmic reticulum showed. Smooth endoplasmic reticulum showed over cytoplasm. 2. Group B Nuclear membrane was more rounded, The cristae of the mitochondria were almost normal shape and electron-density showed compacted. Dilation of inner cavity of rough endoplasmic reticulum showed at the pre-time but formed typical lamellae at the 48Hrs. Smooth endoplasmic reticulum showed over cytoplasm. Therefore, we concluded that chitosan has significantly protective effects in liver to harmful $HgCl_2$.

• Biomolecules & Therapeutics
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• v.2 no.4
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• pp.376-382
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• 1994

Repeated injections of low-doses of mercuric chloride in rats or mice induce polyclonal activation which includes the induction of anti-glomerular basement membrane (GBM) antibodies and circulating immune complex and it results in nephritis. Because this disease is autoimmune mediated disease resulted from immune dysfunction, immunomodulators are used to control the symptoms or to cure the disease. Irpex lacteus Fr. is a kind of new medicinal fungus. The polysaccharide fraction extracted from submerged fermentation of Irpex lacteus Fr. decreased the serum agglutinin, serolysin and IgM plaque forming cells in normal mice. The hitherto obtained clinical results suggested that it significantly improved the oligourea, edema, and hypertension in patients who have nephritis. To elucidate the action-mechanisms of Irpex lacteus Fr., we established the experimental model of HgCl$_2$induced polyclonal activation by intraperitoneal administrations of HgCl$_2$to mice. To assess the immunomodulating effect of Irpex lacteus fraction, we Investigated its effects on the mitogen induced proliferation and IgM PFC counts of splenic lymphocytes in mice during the treatment of HgCl$_2$. The Irpex lacteus polysaccharide reduced the abnormally increased mitogen induced Iymphocyte proliferation and IgM PFCs to almost normal levels. And the Irpex lacteus polysaccharides prevented the increasement of serum immunoglobulin level induced by HgCl$_2$. These data suggested that the Irpex lacteus polysaccharides might have the immunomodulating activity to prevent and /or improve the HgCl$_2$ induced autoimmune disease.

• BMB Reports
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• v.32 no.2
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• pp.203-209
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• 1999

Three-week grown Arabidopsis thaliana leaves were wounded by cutting whole leaves with a razor blade into pieces (about$3\;mm\;{\times}\;3\;mm$) submerged in various solutions, and incubated in a growth chamber for 24 h. We measured and compared activities of several enzymes such as phenylalanine ammonia-lyase (PAL), tyrosine ammonia-lyase (TAL), thioredoxin, thioredoxin reductase, thioltransferase, glutathione reductase, and $NADP^+$ -malate dehydrogenase. PAL activity was decreased in $HgCl_2$-, $CdCl_2$-, and glyphosate-treated leaf slices, and could not be detected after treatment with $CdCl_2$. TAL activity was found to be maximal in the $CdCl_2$-treated leaf slices. Activity of thioredoxin, a small protein known as a cofactor of ribonucleotide reductase and a regulator of photosynthesis, was significantly increased in the $CdCl_2$-treated leaf slices, while thioredoxin reductase activity was maximal in the $HgCl_2$-treated leaf slices. Thioltransferase and glutathione reductase activities were significantly decreased in the $HgCl_2$-treated leaf slices. $NADP^+$ -malate dehydrogenase activity remained relatively constant after the chemical treatments. Our results strongly indicate that sulfhydryl-related and phenylpropanoid-synthesizing enzyme activities are affected by chemical treatments such as hydrogen peroxide, heavy metals, and glyphosate.

• Journal of Life Science
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• v.10 no.3
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• pp.247-253
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• 2000

The effects of acute of marine toxicants on early life of coastal olive flounder were investigated. An increasing order of acute toxicity on embryo- and larva-stages of Paralichtys olivaceus was CdCl2$\mu\textrm{g}$/L and 29 $\mu\textrm{g}$/L, respectively, and those values at larva-stage were estimated 3.5 ng/L, 16.0 nL/L, 10.5 $\mu\textrm{g}$/L and 15.0 $\mu\textrm{g}$/L, respectively.

• Clean Technology
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• v.20 no.3
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• pp.269-276
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• 2014

This study was aimed to develop catalytic system for the dry-based reduction of oxidized mercury ($Hg^{2+}$) to elemental mercury ($Hg^0$) which is one of the most important components comprising mercury continuous emission monitoring system (Hg-CEMS). Based on the standard potential in oxidation-reduction reaction, transition metals including Fe, Cu, Ni and Co were selected as possible candidates for catalyst proceeding spontaneous reduction of $Hg^{2+}$ into $Hg^0$. These transition metal catalysts revealed high activity for reduction of $Hg^{2+}$ into $Hg^0$ in the absence of oxygen in reactant gases. However, their activities were greatly decreased in the presence of oxygen, which was attributed to the transformation of transition metals by oxygen to the corresponding transition metal oxides with less catalytic activity for the reduction of oxidized mercury. Hydrogen supplied to the reactant gases significantly enhanced $Hg^{2+}$ reduction activity even in the presence of oxygen. It might be due to occurrence of combustion reaction between $H_2$ and $O_2$ causing the consumption of $O_2$ at such high reaction temperature at which oxidized mercury reduction reaction took place. Because the system showed high activity for $Hg^{2+}$ reduction to $Hg^0$, which was compatible to that of wet-chemistry technology using $SnCl_2$ solution, the catalytic reduction system of Fe catalyst with the supply of $H_2$ could be employed as a commercial system for the reduction of oxidized mercury to elemental mercury.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.223-229
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• 1992

Mechanistic studies on the metal-exchange reactions of sparteine copper(II) dichloride [$SpCuCl_2$] with Hg(II) ion and Hg(0) metal have been carried out with the aid of Cyclic Voltammetry and UV-visible spectrophotometry. The metal exchange reaction of $SpCuCl_2$ with both Hg(II) ion and Hg(0) metal follows pseudo-first order kinetics. Rate constants and activation parameters of metal exchange reaction have been evaluated and reported. Experimental results indicate that the rate determining step for the exchange reaction is the cleavage of Cu(II)-N bond in the transient binuclear complex of Cu(II) and mercury(II) bound to sparteine ligand.

• Korean Journal of Oriental Medicine
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• v.7 no.1
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• pp.135-144
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• 2001

Objectives : This study was carried out to research the protective effects of Sagunja-Tang(SA) through in vivo experiments, and tried to investigate the relation between oxidation of renal tissues and deficiency of Qi. Methods : Acute renal injury which initiated from free radical induced by $HgCl_2$, were applied to mice and metabolic data were obtained. In order to measure the degree of renal injury, serum level of creatinine, blood urea nitrogen(BUN), total protein(TP) and glucose were measured. Besides, serum level of alanine aminotransferase(AST), aspartate aminotransferase(ALT) were measure too. Lipid peroxidation of renal cortex was examined by measuring malondialdehyde(MDA), a product of lipid peroxidation. Results : SA had protective effects on acute renal injury caused by decrease of glomerular filtration which was initiated by subcutaneous injection of $HgCl_2$. SA protected acute liver injury too. Conclusions : Through this study, we found that SA have healing effects on renal injury of $HgCl_2$ induced oxidative stress that is similar to deficiency of Qi. And further studies have to be followed to certify the mechanisms.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.10a
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• pp.39-43
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• 1997

Mercurous chloride (Hg$_2$Cl$_2$) has many advantages in its applications to acousto-optic, and opto-electronic devices because it has the unique properties of a broad transmisson range, well into the far infra-red, a low acoustic velocity, a large birefringence, and a high acousto-optic figure of merit[1]. Hg$_2$Cl$_2$ has a high vapor pressure, hence single crystals are usually grown by physical vapor transport(PVT) method in closed silica glass ampoules. We discuss the application of the laser Doppler velocimetry to measure the flow field inside a closed ampoule. The experimental results, are discussed its relationship to computational model and compared to their expectations.