• Title/Summary/Keyword: Lead (

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Binding sites for lead ion in staphylococcus epidermidis

  • Kim, Mal-Nam;Sung, Hye-Yoon
    • Journal of Microbiology
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    • v.33 no.3
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    • pp.228-233
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    • 1995
  • As S. epidermidis cell was fractionated into cell wall, cell membrane, and cytoplasm, the cell membrane proved to be the most efficient absorbent for lead ion. Utrasonication was effective, when the cells were treated during their exponential growth. The amount of the lead ion adsorbed in cell membrane decreased as hydrogen ion concentration of solution increased. Protein purified from the cell membrane showed higher adsorption capacity for the lead ion than peptidoglycan, teichoic acid from cell wall, or cell membrane lipid. Modification of carboxyl groups in the membrane protein with ethylenediamine and 1-ethyl-3-carbodiimide hydrochloride resulted in a considerable decrease of lead ion adsorption capability, suggesting that the main binding site for lead ion was the carboxyl groups of protein in cell membrane.

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Effect of Lead Ion on The Hepatic Xanthine Oxidase Activity in Vitro (납이온이 잔틴 옥시다제 활성에 미치는 영향)

  • Huh, Keun;Shin, Uk-Seob;Lee, Sang-Hoon;Ann, Won-Hyo
    • YAKHAK HOEJI
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    • v.39 no.5
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    • pp.521-527
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    • 1995
  • This study was done to determine the effect of lead acetate on the activities of the hepatic cytosofic xanthine oxidase and aldehyde oxidase which were well known as oxygen free radical generating enzyme in vitro. Lead ion accelerated the formation of lipid peroxide and the increment of xanthine oxidase(type O) activity and the type conversion ratio from xanthine dehydrogenase to xanthine oxidase dose-dependently. But xanthine dehydrogenase(type D) activity was decreased. Aldehyde oxidase activity was not changed by lead ion. These data suggested that lead-induced cellular to)dcity may be concerned partially with xanthine oxidase mediated lipid peroxidation.

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Demonstration of an ultrasonic imaging system for molten lead

  • Jonathan Hawes;Jordan Knapp;Robert Burrows;Robert Montague;Paul Wilcox;Hual-Te Chien;Jeff Arndt;Steve Walters
    • Nuclear Engineering and Technology
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    • v.56 no.4
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    • pp.1460-1471
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    • 2024
  • 2D and 3D ultrasonic imaging has so far not been demonstrated in pure molten lead in the open literature. In this study the development of such an ultrasonic device for imaging is outlined and results from testing at 380 ℃ in lead are presented. The main difficulties were found to be achieving then maintaining suitable wetting while ensuring suitable durability of the device, both due to the harsh nature of molten lead and the elevated temperatures. The successful detection and imaging (2D and 3D), of differently shaped targets, where the features were above the size of the transmitted ultrasound beam was demonstrated.

A Study of the Relationships Between Proximity to an Industrial Complex and Blood Lead Levels and Urinary Cadmium Levels (거주지와 산업단지간의 거리와 혈 중 납 농도 및 요 중 카드뮴 농도의 상관관계에 관한 연구)

  • Heo, Jin-A;Kim, Hyo-Mi;Lee, Jong-Tae
    • Journal of Environmental Health Sciences
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    • v.38 no.2
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    • pp.95-104
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    • 2012
  • Objectives: The goal of this study was to investigate the relationships between proximity to an industrial complex and blood lead levels and urinary cadmium levels. Methods: We conducted a questionnaire survey and analyzed blood lead and urinary cadmium levels using Atomic Absorption Spectrometry (AAs). Data was analyzed using logistic regression analysis. All statistical analyses were conducted with SAS software version 9.2. The distance between the residence and an industrial complex was calculated through a Geographical Information System (GIS). Results: A total of 967 residents living near a large petrochemical complex in Ulsan participated. The geometric mean levels of blood lead and urinary cadmium were $1.70{\mu}g/dl$ (male: $1.77{\mu}g/dl$, female: $1.67{\mu}g/dl$), and $0.72{\mu}g/g$ creatinine (male: $0.49{\mu}g/g$ cr. female: $0.89{\mu}g/g$ cr.), respectively. Blood lead and urinary cadmium levels both increased with age and were higher among smokers compared to never smokers. Both significantly showed a decreasing trend with rising income. Results from multiple logistic regression analysis showed that urinary cadmium levels for subjects aged less than 20 years old were negatively associated with distance from the industrial area to the residence. The results, however, indicated that the blood lead levels were positively associated with the distance. Conclusions: The results of this study support that proximity to an industrial complex is related to urinary cadmium values for children. A positive finding with blood lead can be explained by the ambiguity of lead exposure sources in the general environment.

Blood Lead Concentration of Taxi Drivers in Taegu, Korea (대구지역 택시기사들의 혈중 연농도)

  • SaKong, Jun;Kang, Pock-Soo;Chung, Jong-Hak
    • Journal of Preventive Medicine and Public Health
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    • v.23 no.3 s.31
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    • pp.255-261
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    • 1990
  • Taxi drivers are exposed to vehicular exhaust aerosols which are a mar source of atmospheric lead pollution in Korea where lead additives are incorporated in petrol. To investigate the blood lead concentration, their correlation factors and influences on taxi drivers, samples were collected from 90 taxi drivers who were living in the Taegu City, during August, 1989. Blood lead concentration was estimated by the atomic absorption spectrophotometer (IL.551) equipped with flameless furnace atomizer (IL.665). The results were analyzed statistically and compared with control group selected urban population. The mean blood lead concentration of taxi drivers and control group were $26.34{\pm}6.53{mu}g/dl\;and\;20.77{\pm}4.80{\mu}g/dl$ respectively (p<0.01). No significant correlation was observed between the blood lead concentration of taxi drivers and driver career (r=0.093). There were no difference of statistical significance in the blood lead concentration of smokers and nonsmokers.

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A Meta-analysis of the Association between Blood Lead and Blood Pressure (혈중 납과 혈압의 연관성에 관한 메타분석)

  • Koh, Sang-Baek;Nam, Chung-Mo;Choi, Hong-Ryul;Cha, Bong-Suk;Park, Jong-Ku;Jee, Ho-Sung;Kim, Chun-Bae
    • Journal of Preventive Medicine and Public Health
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    • v.34 no.3
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    • pp.262-268
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    • 2001
  • Objectives : To integrate the results of studies which assess an association between blood lead and blood pressure. Methods : We surveyed the existing literature using a MEDLINE search with blood lead and blood pressure as key words, including reports published from January 1980 to December 2000. The criteria for quality evaluation were as follows: 1) the study subjects must have been workers exposed to lead, and 2) both blood pressure and blood lead must have been measured and presented with sufficient details so as to estimate or calculate the size of the association as a continuous variable. Among the 129 articles retrieved, 13 studies were selected for quantitative meta-analysis. Before the integration of each regression coefficient for the association between blood pressure and blood lead, a homogeneity test was conducted. Results : As the homogeneity of studies was rejected in a fixed effect model, we used the results in a random effect model. Our quantitative meta-analysis yielded weighted regression coefficients of blood lead associated with systolic blood pressure and diastolic blood pressure results of 0.0047 (95% confidence interval [CI]: -0.0061, 0.0155) and 0.0004 (95% CI: -0.0031, 0.0039), respectively. Conclusions : The published evidence suggested that there may be a weak positive association between blood lead and blood pressure, but the association is not significant.

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Histological Study on the Effects of the Green-Tea in Rat Liver Toxicated by Lead (녹차가 납 중독된 흰쥐의 간장에 미치는 형태학적 연구)

  • Chung, Kyoung-A;Roh, Young-Bok
    • Applied Microscopy
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    • v.30 no.2
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    • pp.165-172
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    • 2000
  • To investigate the defensive effect of green tea against the lead toxicity, Sprague-Dewley rats (150 gm) were divided into 5 groups; the control group, the group treated with lead for 4 weeks (Group A-1), the group treated with lead and green tea for 4 weeks (Group A-2), the group treated with lead for 8 weeks (Group B-1), and the group treated with lead and green tea for 8 weeks (Group B-2). The lead acetate (500 ppm) was injected two times for one week into the abdomen and green tea solution (3 g/100 ml distilled water) offered freely. In the liver cell, The cristae of mitochondria were enlarged, the rough endoplasmic reticulum (rER) extended and many lysosome observed on the Group A- 1. The cristae of mitochondria were enlarged and many lysosome observed, but nucleus was normal on the Croup A-2. All of observed parts on the Group B-1 deeply wounded by lead than the group A-1. In the Group B-2, the mitochondria and rER were increased in number than the Group B-1 and the nucleus was observed normally.

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Protective Effects of Activated Charcoal on the Acute Damages of Kidney of Mouse by Lead (급성 납 중독된 생쥐의 신장에서 활성탄의 보호효과)

  • Cheong, Min-Ju;Roh, Young-Bok
    • Applied Microscopy
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    • v.36 no.2
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    • pp.57-72
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    • 2006
  • A protective effect of activated charcoal against the acute lead poisoning of kidney was studied in mice. Mice approximately 30 gm in weight were grouped into the control, lead acetate-treated. and the activated charcoal-treated after lead acetate groups. Lead acetate (60mg/kg) and activated charcoal (40mg/kg) were delivered orally. Serum BUN and creatine were measured and ultrastructural alteration of renal tissues were examined by electron microscopy. Activated charcoal were decreased the increase of serum BUN and Creatinine level induced by lead. Lead acetate-treated renal tissues were characterized by the loss of microvilli in the renal tubule tells, irregular nucleus, enlarged and reduced number of mitochodria, enlarged rough endoplasmic reticulum, loss of ribosomes. Cells treated with activated charcoal were similar to those of the control group. In conclusion, activated charcoal may protect the lead-induced toxicity on kidney.

A Study on Antibody Producing by Intoxication of Cadmium Chloride or Lead Acetate in Rat (카드뮴 및 납화합물 중독에 의한 혈액학적 소견과 면양 적혈구에 해한 항체생산 세포수에 미치는 영향)

  • Chung, Yong;Jung, Sung-Kun;Kwon, Sook-Pyo
    • Journal of Preventive Medicine and Public Health
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    • v.15 no.1
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    • pp.89-94
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    • 1982
  • Among the environmental pollutants, cadmium and lead compounds may impair human health. These compounds may inhibit the biological metabolic function of human body and may furthermore cause the disease directly or indirectly. This study was undertaken to investigate the effects of the immune response by intoxication of cadmium chloride and lead acetate. Cadmium chloride (8.8mg/kg, in saline 10ml) and lead acetate (15mg/kg, in saline 10ml) were administered by intraperitoneal injection. After 3 weeks, the rats were intoxicated with the above chemicals and immunized with sheep RBC. After 4 weeks, the immune response of rat spleen cells was measured by the Jerne's technique. The results were obtained as follows; 1. There was no change in leukocyte counts by the intoxication of cadmium chloride or lead acetate. 2. Cadmium chloride or lead acetate reduced hemoglobin contents for most intoxicated and immunized groups. 3. Hematocrits were decreased by the intoxication of cadmium chloride or lead acetate significantly. 4. It was determined that total protein, A/G (Albumin/Globulin), ${\alpha}-,\;{\beta}-\;and\;{\gamma}$-globulins in rat serum were not changed. 5. Intoxication by cadmium chloride or lead acetate reduced the number of hemolytic plaque to the sheep RBC in rat spleen cells. Therefore, antibody producing of rat spleen cells was suppressed by the intoxication of cadmium chloride and lead acetate.

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