• Journal of Korean society of Dental Hygiene
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• v.8 no.4
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• pp.31-41
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• 2008

Steven-Johnson syndrome (SJS) and toxic epidermal necrolysis(TEN) are severe mucocutaneous reaction which are most frequently caused by drugs. Although the incidence of SJS and TEN is known to be relatively low, outcomes may be fatal. A systematic approach is required because morbidity rate is currently increasing and oral lesion is frequent. We investigated the clinical features and outcomes of 6 patients diagnosed as SJS and TEN and referred from the department of dermatology, Chonnam National University Hospital for oral care. Ketoconazol, Ofloxacin, Chlorphenesin, Amoxicillin, Pontal, Harnal, and Ciprofloxacin were suspected as the causative drugs. Average treatment period was 3.2 weeks, and two patients were referred to 'burn-patients' hospital. Most of oral lesion were cured be normal tissue, but scares with discoloration were observed. For intraoral management, antibiotic disinfection and steroid application were performed according to systemic treatment principles. Additionally, ingestion of zinc, antioxidants, and vitamin was recommended. The establishment of oral treatment principles is demanded because it has not been yet. Also, through investigation of drug side effect and careful prescription are required.

• Textile Coloration and Finishing
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• v.31 no.1
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• pp.33-41
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• 2019

In this report, nano-sized catalysts were introduced onto fabric surface to eliminate toxic chemicals assisted by physical adsorption. For chemical removal of toxic compounds, a series of zirconium-containing catalysts were synthesized and treated on fabric to catalyze the hydrolysis and oxidation of target molecules. Antimicrobial was also introduced for the research purpose to prove the compatibility of as-synthesized catalysts with other solutions. Zirconium ligated with hydroxyl group and MOF(Metal-Organic Frameworks) were exploited as catalyst for removal of toxic compounds, while zinc complex was used for an antimicrobial to culminate in a chemical shield. Once fabrics were functionalized, fabrics were washed 2 or 5 times for a washing durability test. The amount of catalyst in textile were measured by ICP-MS and weight increasing ratio of fabrics.

• Journal of Microbiology and Biotechnology
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• v.12 no.6
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• pp.901-908
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• 2002

The relationship between the layered structure of granules in UASB reactors and microbial resistance to toxicity was investigated using disintegrated granules. When no toxic materials were added to the media, the intact and disintegrated granules exhibited almost the same ability to decrease COD and to produce methane. However, when metal ions and organic toxic chemicals were added to a synthetic wastewater, he intact granules were found to be more resistant to toxicity than the disintegrated granules, as determined by the methane production. The difference in resistance between the intact and disintegrated granules was maximal, with toxicant concentrations ranging from 0.5 mM to 2 mM for trichloroethylene with toluene and 5 mM to 20 mM for metal ions (copper, nickel, zinc. chromium, and cadmium ions). The augmented COD removal rate by granulation compared to disintegrated granules was also measured in the treatment of synthetic and real wastewaters; synthetic wastewater, $-2.6\%$; municipal wastewater, $2.8\%$; swine wastewater, $6.4\%$; food wastewater, $25.0\%$; dye works wastewater, $42.9\%$; and landfill leachate, $61.8\%$. Continuous reactor operation also demonstrated that the granules in the UASB reactor were helpful in treating toxic wastewater, such as landfill leachate.

• Journal of Ocean Engineering and Technology
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• v.24 no.5
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• pp.67-74
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• 2010

Chromate conversion coating is a coating technique used to passivate aluminum, zinc, cadmium, copper, silver, magnesium, tin, and their alloys to slow corrosion. The process uses various toxic chromium compounds, which may include hexavalent chromium. The industry is developing less toxic alternatives in order to comply with substance restriction legislation, such as RoHS. One alternative is to develop a Cr-free coating solution. In this study, eco-friendly, Cr-free solutions (urethane solution S-700, organic/inorganic solution with Si LRO-317) were used. Test specimens were dried in a drying oven at $190^{\circ}C$ for 3, 5, 7, and 9 minutes. Corrosion resistance was evaluated using a salt spray test for 72 hours. The results show that the optimum corrosion resistance was achieved at $190^{\circ}C$ for five minutes for EGI and three or five minutes for HDGI, respectively. The adhesive properties of the two types of coating solutions were superior regardless of drying time.

• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.1-15
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• 1995

Tolerance to toxic effects of cadmium(Cd), including lethality has been shown following pretreatment with cadmium and zinc. This study was designed to determine if tolerance also develops to Cd-induced hepatotoxicity and renal toxicity. Three groups of rats(A, B, C), each consisting of 52 rats, were studied and each group was divided into three subgroups(1,2,3), 28 rats for each subgroup. Rats were subcutaneously pretreated with saline(A), $CdCl_2$(0.5 mg/kg, B), and $ZnCl_2$(13.0 mg/kg, C) during time periods of 5 days. At the end of the period, rats were challenged with $CdCl_2$(3.0 and 6.0 mg/kg) by intraperitoneal injection. As for the cadmium levels in rat tissues after 1,3,5,6 days of pretreatments, it was highest in the liver. Then kidney, heart, blood and muscle followed it in that order. After 24, 48 and 96 hours of intraperitoneal injection by challenge doses the concentration of cadmium in liver and kidney increased proportionally to the increase of challenge dosage. However metallothioneins in liver and kidney were increased by the pretreatment of cadmium and zinc. These data indicate the liver is a major target-organ of acute Cd poisoning, and suggest that cadmium induced hepatic injury, via release of Cd-MT, may play an important role in the nephrotoxicity observed in response to short-term exposure to cadmium. This result suggest that increasing cadmium concentrations, gradually accumulating in liver and kidney as the result of the pretreatment, served to induce the synthesis of metallothionein, thus making them resistant to the challenge from cadmium.

• Environmental Analysis Health and Toxicology
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• v.19 no.2
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• pp.191-200
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• 2004

Zinc (Zn) is an essential element in biological process, however inadequate Zn status in general population have been recognized. To update the knowledge for Zn-cadmium (Cd) interaction, we studied the intestinal uptake and transport, and the expression of metal transporter proteins (divalent metal transporter 1, DMT1 ; metal transporter protein 1, MTP1 ; zinc transporter 1, ZnTl ; metallothionein 1 , MT1) in duodenum after Cd exposure using Zn deficient animal model. Rats were led Zn deficient (ZnD, 0.5-1.0 mgZn/kg) or Zn supplemented (ZnS, 50mg Zn/kg) diet for 4 weeks, and followed single administration of $^{109}$ CdCl$_2$orally. The body Zn flatus and tissue Cd concentration were determined at 24 hrs after Cd administration. Total body burden of Cd and Cd absorption index (AI, %) were estimated based on the tissue Cd analyzed. DMT1, MTP1, ZnTl and MT1 mRNA were analyzed by using RT-PCR method. Feeding of Zn deficient diet for 4 weeks produced a reduced body weight gain and a depletion of body Zn. Tissue Cd concentration, body burden of Cd and Cd absorption index were higher in the ZnD diet fed rats than the ZnS diet red rats. Especially, Cd concentration in the small intestine (duodenum, jejunum and ileum) and the colon of FeD diet fed rats were higher markedly than in the FeS diet group. The expression levels of DMT1, MTP1 and ZnT1 mRNA in FeD diet fed rats were similar to the FeS diet. The level of MT1 mRNA expression was significantly lower in the FeD than the FeS diet fed rats. Taken together, theses results indicate that Zn deficiency in diet induce an increased intestinal absorption and tissue retention of Cd, and down -regulate the MT1 expression in the intestine which might be play a part of role in Cd absorption and transport in mammalian. These findings suggest that deficiency of essential metal could be enhanced the toxicity of toxic, non-esstial metals through the metal-metal interaction.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.372-379
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• 2019

We evaluated the toxic effects of phenanthrene (PHE) and zinc undecylenate (ZU) on the population growth rate (r) of the marine diatom, Skeletonema costatum. The r of S. costatum was determined after 96 hrs of exposure to PHE (0, 25, 50, 100, 200 and 300 mg L^-1) and ZU (0, 5, 10, 15, 20 and 25 mg L^-1). The results showed that r in the control (the absence of PHE and ZU) was greater than 0.04, while r in the treatment groups decreased with increasing PHE and ZU concentrations. PHE and ZU were shown to reduce r in a dose-dependent manner, with significant decreases occurring at concentrations above 50 and 10 mg L^-1, respectively. The EC₅₀ values of r in PHE and ZU exposure were 136.13 and 16.95 mg L^-1, respectively. The no observed effect concentrations (NOEC) were 25 and 5 mg L^-1, and the lowest observed effect concentrations (LOEC) were 50 and 10 mg L^-1. These results indicated that concentrations of greater than 50 mg L^-1 of PHE and 10 mg L^-1 of ZU in marine ecosystems induced a toxic effect on the r of S. costatum. These results can serve as useful baseline data for the establishment of safety concentrations of PHE and ZU in marine ecosystems.

• 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.

• Toxicological Research
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• v.13 no.1_2
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• pp.103-110
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• 1997

This study was performed to investigate the effects of cadmium chloride on the acute and chronic toxicity on rats. Several toxic effects of cadmium has been shown following short-term and longterm pretreatment with cadmium and zinc. Four groups of rats (A, B, C, D), each consisting of 16 rats, were studied and each group was divided into four subgroups (1, 2, 3, 4), 4 rats for each subgroup. Rats were subcutaneously pretreated with $CdCl_2$ (0.5 mg/kg, A & C), and $ZnCl_2$ (13.0 mg/kg, B & D) during time periods of 1 weeks (group A & B) and 6 weeks (group C & D). At the end of the period, rats were challenged with $CdCl_2$ (3.0, 6.0 and 9.0 mg/kg, i.p.). After giving the challenge dose, cadmium and metallothionein(MT) concentrations were determined. The concentrations of cadmium were higher in the liver than the kidney irrelevantly to cadmium and zinc pretreatment and increased dose-dependently to the challenge dosage. The metallothioneins showed higher concentrations in the liver than the kidney following cadmium pretreatment and were higher in the long-term pretreatment groups than the short-term pretreatment groups in the liver and the kidney of rats. These data suggest that metallothioneins are induced preferentially in the liver by pretreatment of cadmium and then, formed in the form of Cd-MT, may play an important role in the nephrotoxicity.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.499-502
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• 2013

Trace elements which are essential components of biological structures may also be toxic when present at levels above the amounts required for biological function. In our study, trace element levels were measured with furnace atomic absorption spectrophotometry in 33 newly diagnosed renal cell carcinoma cases (preoperative) and 32 healthy controls. When compared with the control group, it was found that the levels of cadmium (Cd), lead (Pb) were higher and the levels of zinc (Zn), iron (Fe) and manganese (Mn) were lower in the patient group. These changes may be important in the formation of renal cell carcinoma, a question which should be explored with postoperative comparative studies.