• Title/Summary/Keyword: Arsenite

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Simple and Efficient Synthesis of Iron Oxide-Coated Silica Gel Adsorbents for Arsenic Removal: Adsorption Isotherms and Kinetic Study

  • Arifin, Eric;Cha, Jinmyung;Lee, Jin-Kyu
    • Bulletin of the Korean Chemical Society
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    • v.34 no.8
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    • pp.2358-2366
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    • 2013
  • Iron oxide (ferrihydrite, hematite, and magnetite) coated silica gels were prepared using a low-cost, easily-scalable and straightforward method as the adsorbent material for arsenic removal application. Adsorption of the anionic form of arsenic oxyacids, arsenite ($AsO^{2-}$) and arsenate ($AsO{_4}^{3-}$), onto hematite coated silica gel was fitted against non-linear 3-parameter-model Sips isotherm and 2-parameter-model Langmuir and Freundlich isotherm. Adsorption kinetics of arsenic could be well described by pseudo-second-order kinetic model and value of adsorption energy derived from non-linear Dubinin-Radushkevich isotherm suggests chemical adsorption. Although arsenic adsorption process was not affected by the presence of sulfate, chloride, and nitrate anions, as expected, bicarbonate and silicate gave moderate negative effects while the presence of phosphate anions significantly inhibited adsorption process of both arsenite and arsenate. When the actual efficiency to remove arsenic was tested against 1 L of artificial arsenic-contaminated groundwater (0.6 mg/L) in the presence competing anions, the reasonable amount (20 g) of hematite coated silica gel could reduce arsenic concentration to below the WHO permissible safety limit of drinking water of $10{\mu}g/L$ without adjusting pH and temperature, which would be highly advantageous for practical field application.

Trans-acting regulation and Arsenite sensing properties of ars operon

  • Lee, Soo-Chan;Lee, Sung-Jae;Lee, Ho-Sa
    • Proceedings of the Korea Society of Environmental Toocicology Conference
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    • 2001.05a
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    • pp.141-141
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    • 2001
  • The arsenic resistance operon from pMH12 in Klebsiella oxytoca contains two regulatory genes. The first open reading frame for arsR extend up to 348 bp and has a translational product corresponding to a protein of 116 amino acid residue polypeptide with a molecular mass of 13 kDa. And the second ORF for arsD extend up to 360 bp and express a protein of 120 amino anid residue polypeptide with 13kDa. (omitted)

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Inorganic Arsenic Increases Vasoconstriction through Calcium-Sensitization in Vascular Smooth Muscles

  • Lee, M.Y.;Lee, Y.H.;Bae, O.K.;Chung, J.H.
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.164.2-165
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    • 2003
  • Chronic exposure of arsenic is well known to be the cause of cardiovascular disease such as hypertension. In order to investigate the effect of arsenic on blood vessels. we examined whether arsenic affected agonist-induced contraction of aortic rings in isolated organ bath system. Treatment with arsenite increased vasoconstriction induced by phenylephrine or serotonin in a concentration-dependent manner. (omitted)

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Effect of Arsenic on Acetylcholine-Induced Relaxation in Blood Vessels

  • Lee, M.Y.;Chung, S.M.;Bae, O.N.;Chung, J.H.
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.163.2-164
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    • 2003
  • Several epidemiological studies suggested that arsenic exposure was strongly correlated with the development of cardiovascular disease such as hypertension. In order to examine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on agonist-induced vasorelaxation using the isolated rat aortic rings in vitro organ bath system.Treatment with arsenite inhibited acetylcholine-induced relaxation of aortic rings in a concentration-dependent manner. (omitted)

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ARSENIC-INDUCED DYSFUNCTION IN RELAXATION OF BLOOD VESSELS

  • Lee, Moo-Yeol;Jung, Byung-In;Chung, Seung-Min;Bae, Ok-Nam;Chung, Jin-Ho
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2002.11b
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    • pp.155-155
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    • 2002
  • Several epidemiological studies have suggested that exposure to arsenic is strongly correlated with the development of cardiovascular diseases such as hypertension. To determine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on vasorelaxation using isolated rat aortic rings in an organ bath system.(omitted)

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INORGANIC ARSENIC INCREASES VASOCONSTRICTION THROUGH CALCIUM-SENSITIZATION IN VASCULAR SMOOTH MUSCLES

  • Lee, Moo-Yeol;Lee, Young-Ho;Chung, Seung-Min;Bae, Ok-Nam;Chung, Jin-Ho
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2002.11b
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    • pp.156-156
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    • 2002
  • Chronic exposure of arsenic is well known to be the cause of cardiovascular disease such as hypertension. In order to investigate the effect of arsenic on blood vessels, we examined whether arsenic affected agonist-induced contraction of aortic rings in isolated organ bath system.(omitted)

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Ameliorating Effect of Selenium against Arsenic Induced Male Reproductive Toxicity in Rats

  • Jalaludeen, Abdulkadhar Mohamed;Lee, Ran;Lee, Won Young;Kim, Dong Hoon;Song, Hyuk
    • Reproductive and Developmental Biology
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    • v.38 no.3
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    • pp.107-114
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    • 2014
  • Oral exposure of humans by excess amounts of arsenic may cause disturbances of the reproductive system. In the present study, such exposure was modelled in rats, with the support of sperm principal parameters and histopathological observations. Male Sprague-Dawley rats were randomly divided into three groups where the group I was served as a normal control, group II was received sodium meta-arsenite as arsenic (10 mg/kg b.w/day) and a combination of sodium meta-arsenite and sodium selenite (3 mg/kg b.w/day) in group III. After 6 weeks, there was no significant change in testis weight and in total motility of all the three experimental groups, whereas, rapid moving spermatozoa, moderately moving spermatozoa and slow moving spermatozoa were significantly decreased in arsenic treated rats as compared to control rats. The other sperm principal parameters like progressiveness, average path velocity, straightness linear velocity (VSL), curvilinear velocity (VCL), straightness, linearity sperm head elongation ratio, area, linearity amplitude of lateral head department (ALH) and beat cross frequency (BCF) were found to be reduced in arsenic intoxicated rats. These results are not correlated with the histological studies. On oral administration of selenium ameliorated the adverse effects of arsenic as compared to arsenic alone treated rats. Our findings clearly demonstrate that administration of selenium could prevent some of the deleterious effects of arsenic in the testis.