Earlier studies conducted on lead-exposed workers have determined the reticulocyte count (RC) (%), but the parameters of Absolute Reticulocyte Count (ARC), Reticulocyte Index (RI), and Reticulocyte Production Index (RPI) were not reported. This study assessed the effect of lead (Pb) exposure on the status of reticulocyte count indices in workers occupied in lead battery plants. The present cross-sectional study was carried out on 391 male lead battery workers. The blood lead levels (BLL) were determined by using an Atomic Absorption Spectrophotometer. The RC (%) was estimated by using the supravital staining method. The parameters, such as ARC, RI, and RPI, were calculated by using the RC (%) with the red cell indices (RBC count and hematocrit). The levels of RBC count and hematocrit were determined by using an ABX Micros ES-60 hematology analyzer. The levels of reticulocyte count indices - RC (%), ARC, RI, and RPI significantly increased with elevated BLL. The association between BLL and reticulocyte count indices was positive and significant. The results of linear multiple regression analysis showed that the reticulocyte count (${\beta}=0.212$, P < 0.001), ARC (${\beta}=0.217$, P < 0.001), RI (${\beta}=0.194$, P < 0.001), and RPI (${\beta}=0.208$, P < 0.001) were positively associated with BLL. The variable, smoking habits, showed a significant positive association with reticulocyte count indices: RC (%) (${\beta}=0.188$, P < 0.001), ARC (${\beta}=0.174$, P < 0.001), RI (${\beta}=0.200$, P < 0.001), and RPI (${\beta}=0.151$, P < 0.005). The study results revealed that lead exposure may cause reticulocytosis with an increase of reticulocyte count indices.
Exposure to lead, particularly at chronic low-dose levels, is still a major public health concern. The present study is aimed to evaluate the blood lead levels in populations resident in some abandoned mine areas of Chungbuk, Korea. Eight hundreds and sixty-six subjects who reside in abandoned mine area located in Chungbuk, Korea, were enrolled this study. We evaluated the blood lead level according to the age, gender, and working history in mines. For statistical analysis, SPSS ver 12.0 was used. The geometric mean blood lead levels was $2.93\;{\mu}g/{\ell}$ and nobody showed levels over the guidelines of WHO. Ex-smokers and current-smokers showed significantly higher blood lead levels compared to that of non-smokers. The blood lead levels in individuals with a history of working in a mine was higher than those in individuals without such histories. The populations resident in some Chungbuk abadoned mine area showed low levels of lead in blood. This suggest that lead poisoning might not be induced by abandoned mine in Chungbuk, Korea.
In this experiment forty-eight Sprague Dawley male rats were chosen and used in order to measure the growth rates and to see the effects of lead acumulation in their organs resulting from variously controlled lead protein diet. Protein sources were casein and isolated soyprotein (ISP), and each source was divided into three groups : 7% low protein [LP], 20% standard protein (SP) and 40% high protein (HP) groups. The six experimental groups were given lead acetate(25 mg/kg B.W.) and six control groups were given sodium chloride by oral administration 6 times a week for weeks. The results from this experiment were summeraized as following ; 1) Food consumption, weight gain, organ weight and food efficiency ; Lead acetate administration with protein source had no effects on food consumption, weight gain and organ weight . By their different levels of protein, food consumption of LP group was less the that of SP and HP groups after 3 weeks, weight gain of LP group was less than that of SP and HO groups after 1 weeks. The organ weight in LP group was significantly lower than SP and HP groups except teeth and adrenal s. Effect of lead acetate administration on food efficiency have significantly lower in LP-ISP diet and HP -casein diet than other groups only first week. By their different levels LP group showed significantly lower than SP group until 3 weeks. 2) Hematopoietic effect ; The hematopoieteic effect was not influencec by lead acdtate administration and protein source. But the LP group showed a significantly lowe hematopoietic effect than the SP, HP, groups. 3) Accumulation of lead in the liver, kidney, teeth by protein source showed no significantly differences. Accumulation of lead in blood, heart of LP group, spleen of LP and HP groups. femur of SP and HP groups fed with casein diet groups were significantly higher than fed with ISP diet groups. By their different levels of group showed generally higher than SP and HP groups. But accumulation of lead in teeth of HP group was high also.
In this experiment forty-eight Sprague Dawley male rats were chosen and used in order to measure the growth rates and to see the effects of lead acumulation in their organs resulting from variously controlled lead protein diet. Protein sources were casein and isolated soyprotein (ISP), and each source was divided into three groups : 7% low protein [LP], 20% standard protein (SP) and 40% high protein (HP) groups. The six experimental groups were given lead acetate(25 mg/kg B.W.) and six control groups were given sodium chloride by oral administration 6 times a week for weeks. The results from this experiment were summeraized as following ; 1) Food consumption, weight gain, organ weight and food efficiency ; Lead acetate administration with protein source had no effects on food consumption, weight gain and organ weight . By their different levels of protein, food consumption of LP group was less the that of SP and HP groups after 3 weeks, weight gain of LP group was less than that of SP and HO groups after 1 weeks. The organ weight in LP group was significantly lower than SP and HP groups except teeth and adrenal s. Effect of lead acetate administration on food efficiency have significantly lower in LP-ISP diet and HP -casein diet than other groups only first week. By their different levels LP group showed significantly lower than SP group until 3 weeks. 2) Hematopoietic effect ; The hematopoieteic effect was not influencec by lead acdtate administration and protein source. But the LP group showed a significantly lowe hematopoietic effect than the SP, HP, groups. 3) Accumulation of lead in the liver, kidney, teeth by protein source showed no significantly differences. Accumulation of lead in blood, heart of LP group, spleen of LP and HP groups. femur of SP and HP groups fed with casein diet groups were significantly higher than fed with ISP diet groups. By their different levels of group showed generally higher than SP and HP groups. But accumulation of lead in teeth of HP group was high also.
Present experiments were undertaken in order to clarify the clinico-pathological characteristics of lead poisoning in goats. Twenty goats were divided into three experimental groups(A, B and C) and a control(D). The three experimental groups received diets contaminated artificially with 10(A group), 200(B group) and $1,000(C group){\mu}g/g$ of lead for 70 days, respectively. The control group received normal diets. Hair samples collected one or two weeks interval were examed for the lead content. On day 70. all the animals were necropsied and various organs were examined pathoanatomically. In addition, various organs were analyzed for lead, zine, copper, iron and calcium content by atomic absorption spectrophotometry. From these experiments following results were obtained ; The lead content of hair was significantly increased from the $42^{nd}$, $21^{st}$ or $14^{th}$ day in all the three groups, which showed significant correlation with lead content of liver and spleen. The lead content of various organs including kidney, liver, spleen, ileum, bone and abomasum were significantly increased in accordance with the lead contamination. The increase was most prominent in abomasal wall. The zinc and copper content of liver, brain, ileum, skin, kidney, lung or muscle were increased in B and C groups whereas the iron and calcium content showed no significant change. Pathoanatomically, degeneration or necrosis of proximal convoluted tubules of kidney, peripheral necrosis of liver, fundic gland necrosis of abomasum and cerebral edema were observed in B and C groups.
Present experiments were undertaken in order to clarify the clinico-pathological characteristics of lead poisoning in goats. Twenty goats were divided into three experimental groups(A, B and C) and a control(D). The three experimental groups received diets contaminated artificially with 10(A group), 200(B group) and 1,000(C group) ${\mu}g/$ of lead, for 70 days respectively. The control group received normal diets. Blood samples were collected 1 or 2 weeks interval and were examined for anemia(erythrocyte counts, hemoglobin concentrations and hematocrit values) and lead contents of erythrocyte and serum. Urine samples collected similarly with blood were examined for delta-aminolevulinic acid and lead content. Collected samples were analyzed for lead content by atomic absorption spectrophotometry. From these experiments following results were obtained : In group B and C, marked decreases in body weight and feed intake, and diarrhea were observed from the $30^{th}$ day of experimental periods. The B and C groups showed pronounced anemia(decrease in erythrocyte count, hemoglobin concentration and hematocrit value) from the $21^{st}$ or $42^{nd}$ day. In group B and C, the lead content of erythrocytes was increased significantly from the $28^{th}$ or $14^{th}$ day. The lead content of serum was increased significantly from the $42^{nd}$ or $14^{th}$ day in B and C groups. The lead content of urine was increased significantly from the first day in both B and C groups. The urinary delta-aminolevulinic acid content was increased significantly from $14^{th}$ day in both B and C groups.
Objectives: Even though several epidemiological studies have observed positive associations between blood lead levels and homocysteine, no study has examined whether this association differs by the levels of micronutrients, such as folate, vitamin B6, and vitamin B12, which are involved in the metabolism of homocysteine. In this study, we examined the interactions between micronutrients and blood lead on homocysteine levels. Methods: This study was performed with 4089 adults aged ${\geq}20$ years old in the US general population using the National Health and Nutrition Examination Survey 2003-2004. Results: There were significant or marginally significant interactions between micronutrients and blood lead levels on mean homocysteine levels. Positive associations between blood lead and homocysteine were clearly observed among subjects with low levels of folate or low vitamin B6 (p-trend <0.01, respectively). However, in the case of vitamin B12, there was a stronger positive association between blood lead and homocysteine among subjects with high levels of vitamin B12, compared to those with low levels of vitamin B12. In fact, the levels of homocysteine were already high among subjects low in vitamin B12, irrespective of blood lead levels. When we used hyperhomocysteinemia (homocysteine>15 ${\mu}mol/L$) as the outcome, there were similar patterns of interaction, though p-values for each interaction failed to reach statistical significance. Conclusions: In the current study, the association between blood lead and homocysteine differed based on the levels of folate, vitamin B6, or vitamin B12 present in the blood. It may be important to keep sufficient levels of these micronutrients to prevent the possible harmful effects of lead exposure on homocysteine levels.
Greenhouse pot experiments were conducted to evaluate the effects of lime, fly ash and ash(from rice straw) on the cadmium and lead translocation from soil to radish. The soils with low metal contents(Cd 1.52 ppd and Pb 25.37ppm) were prepared and high metal contents (Cd 8.99 rpm and Pb 50.81ppm) were prepared and amended with 0.25%, 0.5%, 1.095, 2.055 each of lime, fly ash and ash. Radishes(Raphanus satiuus) were cultivated and cropped on the soils during 25, 50 and 75 days after sprout, and then cadmium and lead contents of radishes were analyzed by roots and tops. The results obtained are as follows. 1. Lime and ash were effective in raising the soil pH, but fly ash was not effective. 2. The growth of radishes were not impaired by the cadmium and lead contamination but, impaired by soil pH 7.5 or more. 3. Cadmium was accumulated very strongly in radishes and the greater concentration was found in tops than roots, but lead showed no evidence of accumulation in radishes. 4. In general, when the concentrations of lime and ash in soils increased, the uptake of cadmium and lead by radishes decreased, and lime was more effective than ash, while fly ash revealed no effect of reducing the translocation of cadmium and lead from soils to radishes. 5. The uptake of cadmium by radishes decreased more effectively than lead and the uptake of Cd or Pb by radishes grown in the soils with high metal contents decreased more effectively than low metal con tents. 6. Cadmium and lead contents of radishes were negatively correlated with soil pH values and the relationship in cadmium content was stronger than that in lead content.
Kim, Wang-Sun;Lee, Byoung-Hoon;Won, Dae-Ho;Yang, Yeon-Mo
Proceedings of the Korean Institute of Information and Commucation Sciences Conference
/
2010.05a
/
pp.959-962
/
2010
There are a lot of methods available in designing PID(Proportional-Integral-Derivative) and Lead/Lag controllers in the industrial field of technology because of their useful advantages such as simplicity and robustness. In an early stage of development process, a computational simulation approach is a very efficient tool for the designs of the controllers. Thus, in this paper we propose a cost-effective, and practically efficient. The PID and Lead/Lag controllers. To show the effectiveness of the proposed Lead/Lag controller, we compare and contrast of the simulation results of each controller with the Matlab simulator. Although we have only considered the DC motors for the controllers, but it could be extended in future developments to more complex plants. As a result, the proposed frameworks could be used to solve industrial problems such as a reduction in development cycle time and minimizing system errors.
Journal of the Korea Academia-Industrial cooperation Society
/
v.11
no.11
/
pp.4115-4120
/
2010
In manual inspection of Lead Screw of computers many workers are needed to inspect samples, and its main disadvantage is that such types of inspection system not only gives low production, but also gives low perfection. Besides, in manual inspection system, the inspection cost of samples is higher than that of the automatic inspection system. Therefore, in this study to compensate these shortcomings, an automatic inspection system is developed. For the inspection of the surfaces and different dimensional parameters of computer Lead screw, a $360^{\circ}$ rotating machine vision system is developed. From the detailed analysis of the inspection results using the present developed inspection system, it is observed that the developed Lead Screw automatic inspection system is superior to those of manually inspection system.
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