In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put resi...In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put residents, especially children, at the highest risk. Principal routes of exposure were incidental ingestion and inhalation of contaminated soil and dusts. Several Nigerian and international health organizations collaborated to reduce lead exposures through environmental remediation and medical treatment. The contribution of contaminated food to total lead exposure was assessed during the environmental health response. Objectives of this investigation were to assess the influence of cultural/dietary habits on lead exposure pathways and estimate the contribution of contaminated food to children＇s blood lead levels（BLLs）. A survey of village dietary practices and staple food lead content was conducted to determine dietary composition, caloric intakes, and lead intake. Potential blood lead increments were estimated using bio-kinetic modeling techniques. Most dietary lead exposure was associated with contamination of staple cereal grains and legumes during post-harvest processing and preparation in contaminated homes. Average post-harvest and processed cereal grain lead levels were 0.32 mg/kg and 0.85 mg/kg dry weight, respectively. Age-specific food lead intake ranged from 7 to 78 μg/day. Lead ingestion and absorption were likely aggravated by the dusty environment, fasting between meals, and nutritional deficiencies. Contamination of staple cereal grains by highly bioavailable pulverized ores could account for as much as 11%–34% of children＇s BLLs during the epidemic, and were a continuing source after residential soil remediation until stored grain inventories were exhausted.展开更多
[ Objective] To investigate the effects of Newcastle disease vaccination and lead exposure on growth and development of egg yellow feather quail. [ Method] Ninety 14-day-old quails were assigned randomly to 10 groups ...[ Objective] To investigate the effects of Newcastle disease vaccination and lead exposure on growth and development of egg yellow feather quail. [ Method] Ninety 14-day-old quails were assigned randomly to 10 groups （ n = 9）, and they fed and drunk at liberty. A 2 ×5 factorial design was used. The quail immunized with ND vaccine and those non-immunized were exposed to lead at a dosage of 0, 50,500, 1 000 and 2 000 mg/L, respectively. [Result] The ND immunization reduced body weight significantly （ P 〈 0.01 ） and increased liver index and serum levels of hy- aluronic acid in quail within 1 -2 weeks post inoculation. The quail exposed to 2 000 mg/L lead acetate had significantly lower body weight than the control （ P 〈 0.01 ）. From 7 weeks old, the same inhibitory effect was observed in the quail＇exposed to lead at different dosages （ P 〈 0.01 ）. In addition, the lead poisoning could cause decreased feed intake, depilation, gonadal dysgenesis, and increased serum levels of hyaluronic acid. [ Conduslon] The inhibitory effect of ND vaccination on growth of quail occurs within 1 -2 weeks post inoculation; thus, the effects of immune stress should not be worried in quail production. The lead poisoning has significant effects on body weight and feed intake of quail, and lead dosage and duration affect the inhibitory effects of lead. Gonadal dysgenesis is an important indicator of lead poisoning in. quail. The serum levels of hyaluronic acid can be used to determine whether the quail have been immunized with ND vaccine or have contacted lead pollutants.展开更多
This study explored the association between the lncRNA HOTAIR polymorphism and susceptibility to lead poisoning in a Chinese population. We speculated that lead poisoning caused elevated levels of oxidative stress, wh...This study explored the association between the lncRNA HOTAIR polymorphism and susceptibility to lead poisoning in a Chinese population. We speculated that lead poisoning caused elevated levels of oxidative stress, which, in turn, activate the HOTAIR gene to cause apoptosis. Three lncRNA HOTAIR tagSNPs（rs7958904, rs4759314, and rs874945） were genotyped by TaqM an genotyping technology in 113 lead-sensitive and 113 lead-resistant Chinese workers exposed to lead. Rs7958904 was significantly associated with susceptibility to lead poisoning（P = 0.047）. The rs7958904 G allele had a protective effect compared with the C allele and reduced the risk of lead poisoning（P = 0.016）. Rs7958904 may act as a potential biomarker for predicting the risk of lead poisoning and distinguishing lead-sensitive individuals from lead-resistant individuals.展开更多
Lead poisoning caused by a foreign body is rare. Foreign bodies that are ingested typically pass without consequence or awareness by the patient [1]. There are few documented cases of lead poisoning from an ingested f...Lead poisoning caused by a foreign body is rare. Foreign bodies that are ingested typically pass without consequence or awareness by the patient [1]. There are few documented cases of lead poisoning from an ingested foreign body lodged in the appendix. Screening for lead poisoning is mandated by New York State at annual well person exams for children ages 6 months to 6 years [2]. We present a case of a 2-year-old male who was found to have elevated lead levels during a routine well-child visit. An abdominal X-ray was obtained as part of routine follow up for elevated lead levels and a foreign body was found in the right lower quadrant. After unsuccessful attempt to flush the foreign body out with golytely, a CT abdomen/ pelvis was obtained. The foreign body was localized in the appendix. The patient was subsequently taken to surgery for an appendectomy to remove the foreign body. This case is a demonstration of the positive effects of the lead screening guidelines of New York.展开更多
Objective To define the prevalence, severity and risk factors for lead poisoning in new immigrant children from the mainland of China to Hong Kong, China.Methods New immigrant children from the mainland of China und...Objective To define the prevalence, severity and risk factors for lead poisoning in new immigrant children from the mainland of China to Hong Kong, China.Methods New immigrant children from the mainland of China under 18 years of age were invited to join the study. Their growth parameters and venous blood lead levels (BLL) were measured within 7 days of arrival. Those with elevated BLL i.e. 】10?μg/dl (0.48?μmol/L) were assessed for signs, symptoms and risk factors of lead poisoning. Education on the prevention of lead poisoning and follow up BLL measurements were offered until their BLL normalized.Results Four hundred and fifty-seven children were recruited. Among them, 18.1% and 2.6% had BLL 】0.48 and 0.71?μmol/L, respectively. None had BLL 】0.96?μmol/L. Possible risk factors included contaminated drinking water (19%), herb ingestion (17.5%), pica, playing in dumping grounds, residing near paint factories or highways, habitual inhalation of car exhaust and cooking with petroleum. Symptoms and signs included abdominal pain, headache, short stature, and learning difficulties but did not correlate with BLL. None required treatment except for counseling on the avoidance of risk factors. About 94.7% showed a reduction in BLL 2-3 months after arrival and before counseling. All had normalized BLL by 9 months except 1 who had an X-ray feature of lead line.Conclusions Lead poisoning is common in new immigrant children from the mainland of China. Environmental factors were most important while behavioral factors like regular herb ingestion might have contributed to the persistence of high BLL in the minority.展开更多
Previous studies have shown that chrysophanol protects against learning and memory impairments in lead-exposed adult mice. In the present study, we investigated whether chrysophanol can alleviate learning and memory d...Previous studies have shown that chrysophanol protects against learning and memory impairments in lead-exposed adult mice. In the present study, we investigated whether chrysophanol can alleviate learning and memory dysfunction and hippocampal neuronal injury in lead-exposed neonatal mice. At the end of lactation, chrysophanol（0.1, 1.0, 10.0 mg/kg） was administered to the neonatal mice by intraperitoneal injection for 15 days. Chrysophanol significantly alleviated injury to hippocampal neurons and improved learning and memory abilities in the lead-poisoned neonatal mice. Chrysophanol also significantly decreased lead content in blood, brain, heart, spleen, liver and kidney in the lead-exposed neonatal mice. The levels of malondialdehyde in the brain, liver and kidney were significantly reduced, and superoxide dismutase and glutathione peroxidase activities were significantly increased after chrysophanol treatment. Collectively, these findings indicate that chrysophanol can significantly reduce damage to hippocampal neurons in lead-exposed neonatal mice.展开更多
Appropriate selection and measurement of lead biomarkers of exposure are critically important for health care management purposes,public health decision making,and primary prevention synthesis.Lead is one of the neuro...Appropriate selection and measurement of lead biomarkers of exposure are critically important for health care management purposes,public health decision making,and primary prevention synthesis.Lead is one of the neurotoxicants that seems to be involved in the etiology of psychologies.Biomarkers are generally classified into three groups:biomarkers of exposure,effect,and susceptibility.The main body compartments that store lead are the blood,soft tissues,and bone;the half-life of lead in these tissues is measured in weeks for blood,months for soft tissues,and years for bone.Within the brain,lead-induced damage in the prefrontal cerebral cortex,hippocampus,and cerebellum can lead to a variety of neurological disorders,such as brain damage,mental retardation,behavioral problems,nerve damage,and possibly Alzheimer’s disease,Parkinson’s disease,and schizophrenia.This paper presents an overview of biomarkers of lead exposure and discusses the neurotoxic effects of lead with regard to children and adults.展开更多
After intraperitoneal injection of 20 mg/kg lead acetate, rats received 8 weeks of treadmill exercise （15-22 m/min, 25-64 minutes） and/or treadmill exercise at 1.6 km/h until exhaustion. The markers related to neuro...After intraperitoneal injection of 20 mg/kg lead acetate, rats received 8 weeks of treadmill exercise （15-22 m/min, 25-64 minutes） and/or treadmill exercise at 1.6 km/h until exhaustion. The markers related to neurotoxicity were measured by enzyme-linked immunosorbent assay method. 8 weeks of treadmill exercise significantly increased brain-derived neurotrophic factor level in the hippocampus （P = 0.04） and plasma level of total antioxidant capacity of rats exposed to lead acetate （P 〈 0.001）, and significantly decreased plasma level of malondialdehyde （P 〈 0.001）. Acute exercise only decreased the hippocampal malondialdehyde level （P = 0.09） and increased brain-derived neurotrophic factor level in the hippocampus （P = 0.66）. Acute exercise also enhanced the total antioxidant capacity in rats exposed to lead acetate, insignificantly （P = 0.99）, These findings suggest that chronic treadmill exercise can significantly decrease neurotoxicity and alleviate oxidative stress in rats exposed to lead acetate. However, acute endurance exercise was not associated with these beneficial effects.展开更多
Objective To examine the effects of Pb2+ on N-methyl-D-aspartate (NMDA)-, K+- and quisqualate(QA)/kainite(KA)-induced increases in intracellular free calcium concentration ([Ca2+],) in cultured fetal rat hippocampal n...Objective To examine the effects of Pb2+ on N-methyl-D-aspartate (NMDA)-, K+- and quisqualate(QA)/kainite(KA)-induced increases in intracellular free calcium concentration ([Ca2+],) in cultured fetal rat hippocampal neurons in order to explain the cognitive and learning deficits produced by this heavy metal. Methods Laser scanning confocal microscopy was used. Results The results clearly demonstrated that adding Pb2+ before or after NMDA/glycine stimulation selectively inhibited the stimulated increases in [Ca2+], in a concentration-dependent manner. In contrast, Pb2+ treatment did not markedly affect increases in [Ca2+], induced by an admixture of QA and KA. The minimal inhibitory effect of Pb2+ occurred at 1 μmol/L, and more than seventy percent abolition of the NMDA-stimulated increase in [Ca2+]; was observed at 100 Jμmoll/L Pb2+. Evaluation of Pb2+-induced increase in [Ca2+], response to elevating extracellular concentrations of NMDA, glycine or calcium revealed that Pb2+ was a noncompetitive antagonist of both NMDA and glycine, and a competitive antagonist of Ca2+ at NMDA receptor channels. In addition. Pb2+ inhibited depolarization-evoked increases in [Ca2+], mediated by K+ stimulation(30μmol/L). indicating that Pb2+ also depressed the voltage-dependent calcium channels. Also, the results showed that Pb2+ appeared to be able to elevate the resting levels of [Ca2+|, in cultured neurons, implying a reason for Pb2+-enhanced spontaneous release of several neurotransmitters reported in several previous studies. Conclusion Lead can inhibit NMDA-. K+-, QA/KA-jnduced increases in intracellular [Ca2+], in cultured hippocampal neurons.展开更多
BaO is the most common consideration in the preparation of newcrystal glass for getting rid of lead content in the glass andceramic wares to protect hu- man health and environment. But forkeeping the glass products...BaO is the most common consideration in the preparation of newcrystal glass for getting rid of lead content in the glass andceramic wares to protect hu- man health and environment. But forkeeping the glass products' properties to meet the requirements ofthe tradi- tional crystal glass, B_2O_3, Al_2O_3, TiO_2, SrO and ZnOetc (at a special ratio) had been researched with BaO to con- stitutea mixture to replace the lead content in the glass compositions.展开更多
The study treated 72 s,rague-Dawley rats that were divided into 4 groups, one controlgroup and low, middle and higa dose groups, through drinking lead acetate solutions for threemonths. On the basis of founding subcl...The study treated 72 s,rague-Dawley rats that were divided into 4 groups, one controlgroup and low, middle and higa dose groups, through drinking lead acetate solutions for threemonths. On the basis of founding subclinical lead poisoning model, behavioral toxicological testwhich consisted of neurobehavioral functions, neuroelectrophysiology and neurobiochemistry wascarried out. The results indicabo that low lvel lead exposure could result in the obvious changes orneurobehavioral function, neuroelectrophyslology and ueurobiochemistry, and the changes of neurobeltavioral runctiou had close correlatiom with P6B, Zap, NCV and DA, and they also had promlnant dose-response relatiouskips. The results suggested that the indexes of neurobehavioral functionmight be cousldered as early, semitive indexes for subolinical'lead poisoning. The combination ofneurobehavioral function with neuroectrophysiology could be used to evaluate the early neurotic toxicity of lead. The results also suggested that the change of dopamine metabolism of the central nervous system (CNS) might be one of the biological foundation of lead neurotic toxicity which changedthe neurobehavioral function of laboratory rats.展开更多
The experiment was conducted to approve the efficacy of functional compound recipe liquid of eliminating lead andcalcium to eliminate lead in rats.Total 120 rats were divided into six groups according to weight:blank ...The experiment was conducted to approve the efficacy of functional compound recipe liquid of eliminating lead andcalcium to eliminate lead in rats.Total 120 rats were divided into six groups according to weight:blank group(CK),negative group(ND),positive group(PD)and high group(HD,6.67Mg kg1 BW d),middle group(MD,3.33 Mg kg1 BW d')and low group(LD,1.67 Mg kg1 BW·d1 three groups).Except CK,other groups were drunk 0.24%Pb(AC)»in which rats were lled with functionalcompound recipe liquid to eliminate lead and DSMA was added to positive group(PD).On the 20th day,the blood was collectedfrom the tail.on the 40th day,the whole blood was collected from eyeball.After executed,liver and blood were collected to determinethe content of lead and calcium.Results showed that lead contents in blood and liver of three dosage groups obviously decreasedcompared with ND and there was signi cant difference between any two groups of three dosage groups(Pc0.01).Meanwhile,thecalcium concentration increased in three dosage groups.It is concluded that the fumctional compound recipe liquid of eliminating leadhas the evident function of eliminating lead and can promote calcium absorption.展开更多
Hundreds of children died in 2010 due to suspected lead poisoning from mining sources in Zamfara State among epidemiological concerns. Evaluating ecological and human health risks of heavy metals levels in sampled foo...Hundreds of children died in 2010 due to suspected lead poisoning from mining sources in Zamfara State among epidemiological concerns. Evaluating ecological and human health risks of heavy metals levels in sampled food crops harvested near two abandoned Lead-Zinc mining sites at Logo Benue State is crucial. <i>Abelmoschus esculentus</i>, <i>Carica papaya</i>, <i>Manihot esculenta</i>, and <i>Zea mays</i> were sampled, prepared, and analyzed for four heavy metals using the Atomic Absorption Spectrophotometric method. The mean data from the analysis of variance was subjected to ecological and health risk models. Pb means value ranged from <i>Carica papaya</i> Peel 0.46 ± 0.011 mg/kg to 1.30 ± 0.01 mg/kg in <i>Zea mays</i> seed. Zn was highest in <i>Carica papaya</i> flesh 0.50 ± 0.01 mg/kg, and lowest in <i>Manihot esculenta</i> peels and its flesh 0.12 ± 0.000 mg/kg. Hg and Cd were below detectable levels. <i>Zea mays</i> <i>seeds</i> (1.001) had the highest Pd bioaccumulation factor. BAF of zinc and ecological indices were <1. Daily Intake of Metals were all <1, however, Hazard Quotient (HQ) of Pb was ≥1 in <i>Manihot esculenta</i> flesh 1.143 and Zea mays at 1714. Cancer Risks were within permissible range (10<sup>-4</sup> - 10<sup>-6</sup>). Health Risk result indicates communities around the mining area may be at risk of lead poisoning therefore due to high contamination of samples, routine checks on heavy metals especially lead is recommended to prevent excessive bioaccumulation in the body.展开更多
The use of lead in ammunition for hunting exposes waterfowl to lead poisoning (plumbism) by accidental consumption of shotgun pellets. To test this hypothesis we sampled 18 liver tissue samples of Snow Goose (Chen cae...The use of lead in ammunition for hunting exposes waterfowl to lead poisoning (plumbism) by accidental consumption of shotgun pellets. To test this hypothesis we sampled 18 liver tissue samples of Snow Goose (Chen caerulescens) collected during the 2012-2013 hunting season in a wetland near the city of Durango, Mexico. We quantified liver lead levels using an atomic absorption spectrophotometer and portions of liver were fixed and stained for their histological study. Average lead concentration (in dry weight) were under the normal range (mean = 0.73 ± 0.2, standard error) which do not represent any risk of poisoning. Liver tissue injuries were not observed in the histopathological analysis, suggesting no reaction to a xenobiotic agent such as lead. Gastrointestinal content analysis showed lead pellet in the gizzard of one individual, but we could not find a relationship between pellet ingestion and lead concentration in the liver. Although the results did not provide evidences of lethal or sublethal effects caused by lead poisoning, they show a possible risk due to the presence of lead pellets in the digestive tract.展开更多
文摘In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put residents, especially children, at the highest risk. Principal routes of exposure were incidental ingestion and inhalation of contaminated soil and dusts. Several Nigerian and international health organizations collaborated to reduce lead exposures through environmental remediation and medical treatment. The contribution of contaminated food to total lead exposure was assessed during the environmental health response. Objectives of this investigation were to assess the influence of cultural/dietary habits on lead exposure pathways and estimate the contribution of contaminated food to children＇s blood lead levels（BLLs）. A survey of village dietary practices and staple food lead content was conducted to determine dietary composition, caloric intakes, and lead intake. Potential blood lead increments were estimated using bio-kinetic modeling techniques. Most dietary lead exposure was associated with contamination of staple cereal grains and legumes during post-harvest processing and preparation in contaminated homes. Average post-harvest and processed cereal grain lead levels were 0.32 mg/kg and 0.85 mg/kg dry weight, respectively. Age-specific food lead intake ranged from 7 to 78 μg/day. Lead ingestion and absorption were likely aggravated by the dusty environment, fasting between meals, and nutritional deficiencies. Contamination of staple cereal grains by highly bioavailable pulverized ores could account for as much as 11%–34% of children＇s BLLs during the epidemic, and were a continuing source after residential soil remediation until stored grain inventories were exhausted.
基金funded by the Key Scientific and Technological Project of Henan Province ( 082102130002)
文摘[ Objective] To investigate the effects of Newcastle disease vaccination and lead exposure on growth and development of egg yellow feather quail. [ Method] Ninety 14-day-old quails were assigned randomly to 10 groups （ n = 9）, and they fed and drunk at liberty. A 2 ×5 factorial design was used. The quail immunized with ND vaccine and those non-immunized were exposed to lead at a dosage of 0, 50,500, 1 000 and 2 000 mg/L, respectively. [Result] The ND immunization reduced body weight significantly （ P 〈 0.01 ） and increased liver index and serum levels of hy- aluronic acid in quail within 1 -2 weeks post inoculation. The quail exposed to 2 000 mg/L lead acetate had significantly lower body weight than the control （ P 〈 0.01 ）. From 7 weeks old, the same inhibitory effect was observed in the quail＇exposed to lead at different dosages （ P 〈 0.01 ）. In addition, the lead poisoning could cause decreased feed intake, depilation, gonadal dysgenesis, and increased serum levels of hyaluronic acid. [ Conduslon] The inhibitory effect of ND vaccination on growth of quail occurs within 1 -2 weeks post inoculation; thus, the effects of immune stress should not be worried in quail production. The lead poisoning has significant effects on body weight and feed intake of quail, and lead dosage and duration affect the inhibitory effects of lead. Gonadal dysgenesis is an important indicator of lead poisoning in. quail. The serum levels of hyaluronic acid can be used to determine whether the quail have been immunized with ND vaccine or have contacted lead pollutants.
基金financially supported by Jiangsu Province Special Project of Clinical Science and Technology[grant project number BL2014082]supported by the Fundamental Research Funds for the Central UniversitiesJiangsu Province Ordinary University Graduate Student Scientific Research Innovation Projects[grant project number SJZZ16-0035]
文摘This study explored the association between the lncRNA HOTAIR polymorphism and susceptibility to lead poisoning in a Chinese population. We speculated that lead poisoning caused elevated levels of oxidative stress, which, in turn, activate the HOTAIR gene to cause apoptosis. Three lncRNA HOTAIR tagSNPs（rs7958904, rs4759314, and rs874945） were genotyped by TaqM an genotyping technology in 113 lead-sensitive and 113 lead-resistant Chinese workers exposed to lead. Rs7958904 was significantly associated with susceptibility to lead poisoning（P = 0.047）. The rs7958904 G allele had a protective effect compared with the C allele and reduced the risk of lead poisoning（P = 0.016）. Rs7958904 may act as a potential biomarker for predicting the risk of lead poisoning and distinguishing lead-sensitive individuals from lead-resistant individuals.
文摘Lead poisoning caused by a foreign body is rare. Foreign bodies that are ingested typically pass without consequence or awareness by the patient [1]. There are few documented cases of lead poisoning from an ingested foreign body lodged in the appendix. Screening for lead poisoning is mandated by New York State at annual well person exams for children ages 6 months to 6 years [2]. We present a case of a 2-year-old male who was found to have elevated lead levels during a routine well-child visit. An abdominal X-ray was obtained as part of routine follow up for elevated lead levels and a foreign body was found in the right lower quadrant. After unsuccessful attempt to flush the foreign body out with golytely, a CT abdomen/ pelvis was obtained. The foreign body was localized in the appendix. The patient was subsequently taken to surgery for an appendectomy to remove the foreign body. This case is a demonstration of the positive effects of the lead screening guidelines of New York.
文摘Objective To define the prevalence, severity and risk factors for lead poisoning in new immigrant children from the mainland of China to Hong Kong, China.Methods New immigrant children from the mainland of China under 18 years of age were invited to join the study. Their growth parameters and venous blood lead levels (BLL) were measured within 7 days of arrival. Those with elevated BLL i.e. 】10?μg/dl (0.48?μmol/L) were assessed for signs, symptoms and risk factors of lead poisoning. Education on the prevention of lead poisoning and follow up BLL measurements were offered until their BLL normalized.Results Four hundred and fifty-seven children were recruited. Among them, 18.1% and 2.6% had BLL 】0.48 and 0.71?μmol/L, respectively. None had BLL 】0.96?μmol/L. Possible risk factors included contaminated drinking water (19%), herb ingestion (17.5%), pica, playing in dumping grounds, residing near paint factories or highways, habitual inhalation of car exhaust and cooking with petroleum. Symptoms and signs included abdominal pain, headache, short stature, and learning difficulties but did not correlate with BLL. None required treatment except for counseling on the avoidance of risk factors. About 94.7% showed a reduction in BLL 2-3 months after arrival and before counseling. All had normalized BLL by 9 months except 1 who had an X-ray feature of lead line.Conclusions Lead poisoning is common in new immigrant children from the mainland of China. Environmental factors were most important while behavioral factors like regular herb ingestion might have contributed to the persistence of high BLL in the minority.
基金financially supported by the Science and Technology Commission Foundation of Zhangjiakou City,No.1021098Dthe Medical Scientific Research Project of Health Bureau of Hebei Province,No.20100144+2 种基金the Natural Science Foundation of Hebei Province,No.H2012405016the Innovative Talents Project of Hebei North University,No.CXRC1325the Major Projects of Hebei North University,No.ZD201310
文摘Previous studies have shown that chrysophanol protects against learning and memory impairments in lead-exposed adult mice. In the present study, we investigated whether chrysophanol can alleviate learning and memory dysfunction and hippocampal neuronal injury in lead-exposed neonatal mice. At the end of lactation, chrysophanol（0.1, 1.0, 10.0 mg/kg） was administered to the neonatal mice by intraperitoneal injection for 15 days. Chrysophanol significantly alleviated injury to hippocampal neurons and improved learning and memory abilities in the lead-poisoned neonatal mice. Chrysophanol also significantly decreased lead content in blood, brain, heart, spleen, liver and kidney in the lead-exposed neonatal mice. The levels of malondialdehyde in the brain, liver and kidney were significantly reduced, and superoxide dismutase and glutathione peroxidase activities were significantly increased after chrysophanol treatment. Collectively, these findings indicate that chrysophanol can significantly reduce damage to hippocampal neurons in lead-exposed neonatal mice.
文摘Appropriate selection and measurement of lead biomarkers of exposure are critically important for health care management purposes,public health decision making,and primary prevention synthesis.Lead is one of the neurotoxicants that seems to be involved in the etiology of psychologies.Biomarkers are generally classified into three groups:biomarkers of exposure,effect,and susceptibility.The main body compartments that store lead are the blood,soft tissues,and bone;the half-life of lead in these tissues is measured in weeks for blood,months for soft tissues,and years for bone.Within the brain,lead-induced damage in the prefrontal cerebral cortex,hippocampus,and cerebellum can lead to a variety of neurological disorders,such as brain damage,mental retardation,behavioral problems,nerve damage,and possibly Alzheimer’s disease,Parkinson’s disease,and schizophrenia.This paper presents an overview of biomarkers of lead exposure and discusses the neurotoxic effects of lead with regard to children and adults.
文摘After intraperitoneal injection of 20 mg/kg lead acetate, rats received 8 weeks of treadmill exercise （15-22 m/min, 25-64 minutes） and/or treadmill exercise at 1.6 km/h until exhaustion. The markers related to neurotoxicity were measured by enzyme-linked immunosorbent assay method. 8 weeks of treadmill exercise significantly increased brain-derived neurotrophic factor level in the hippocampus （P = 0.04） and plasma level of total antioxidant capacity of rats exposed to lead acetate （P 〈 0.001）, and significantly decreased plasma level of malondialdehyde （P 〈 0.001）. Acute exercise only decreased the hippocampal malondialdehyde level （P = 0.09） and increased brain-derived neurotrophic factor level in the hippocampus （P = 0.66）. Acute exercise also enhanced the total antioxidant capacity in rats exposed to lead acetate, insignificantly （P = 0.99）, These findings suggest that chronic treadmill exercise can significantly decrease neurotoxicity and alleviate oxidative stress in rats exposed to lead acetate. However, acute endurance exercise was not associated with these beneficial effects.
基金This work was supported by the Chinese Academy of Preventive Medicine Fund.
文摘Objective To examine the effects of Pb2+ on N-methyl-D-aspartate (NMDA)-, K+- and quisqualate(QA)/kainite(KA)-induced increases in intracellular free calcium concentration ([Ca2+],) in cultured fetal rat hippocampal neurons in order to explain the cognitive and learning deficits produced by this heavy metal. Methods Laser scanning confocal microscopy was used. Results The results clearly demonstrated that adding Pb2+ before or after NMDA/glycine stimulation selectively inhibited the stimulated increases in [Ca2+], in a concentration-dependent manner. In contrast, Pb2+ treatment did not markedly affect increases in [Ca2+], induced by an admixture of QA and KA. The minimal inhibitory effect of Pb2+ occurred at 1 μmol/L, and more than seventy percent abolition of the NMDA-stimulated increase in [Ca2+]; was observed at 100 Jμmoll/L Pb2+. Evaluation of Pb2+-induced increase in [Ca2+], response to elevating extracellular concentrations of NMDA, glycine or calcium revealed that Pb2+ was a noncompetitive antagonist of both NMDA and glycine, and a competitive antagonist of Ca2+ at NMDA receptor channels. In addition. Pb2+ inhibited depolarization-evoked increases in [Ca2+], mediated by K+ stimulation(30μmol/L). indicating that Pb2+ also depressed the voltage-dependent calcium channels. Also, the results showed that Pb2+ appeared to be able to elevate the resting levels of [Ca2+|, in cultured neurons, implying a reason for Pb2+-enhanced spontaneous release of several neurotransmitters reported in several previous studies. Conclusion Lead can inhibit NMDA-. K+-, QA/KA-jnduced increases in intracellular [Ca2+], in cultured hippocampal neurons.
基金Supported by the Youth Foundation of Beijing Graduate School of Wuhan University of Technology(No.97-QW)
文摘BaO is the most common consideration in the preparation of newcrystal glass for getting rid of lead content in the glass andceramic wares to protect hu- man health and environment. But forkeeping the glass products' properties to meet the requirements ofthe tradi- tional crystal glass, B_2O_3, Al_2O_3, TiO_2, SrO and ZnOetc (at a special ratio) had been researched with BaO to con- stitutea mixture to replace the lead content in the glass compositions.
文摘The study treated 72 s,rague-Dawley rats that were divided into 4 groups, one controlgroup and low, middle and higa dose groups, through drinking lead acetate solutions for threemonths. On the basis of founding subclinical lead poisoning model, behavioral toxicological testwhich consisted of neurobehavioral functions, neuroelectrophysiology and neurobiochemistry wascarried out. The results indicabo that low lvel lead exposure could result in the obvious changes orneurobehavioral function, neuroelectrophyslology and ueurobiochemistry, and the changes of neurobeltavioral runctiou had close correlatiom with P6B, Zap, NCV and DA, and they also had promlnant dose-response relatiouskips. The results suggested that the indexes of neurobehavioral functionmight be cousldered as early, semitive indexes for subolinical'lead poisoning. The combination ofneurobehavioral function with neuroectrophysiology could be used to evaluate the early neurotic toxicity of lead. The results also suggested that the change of dopamine metabolism of the central nervous system (CNS) might be one of the biological foundation of lead neurotic toxicity which changedthe neurobehavioral function of laboratory rats.
基金Supported by Heilongjiang Daqing Program(DQGX08YF027)Technology Key Program of Heilongjiang Province(GB04C109-01)Daqing Development Zone Program(SGG2008-037)
文摘The experiment was conducted to approve the efficacy of functional compound recipe liquid of eliminating lead andcalcium to eliminate lead in rats.Total 120 rats were divided into six groups according to weight:blank group(CK),negative group(ND),positive group(PD)and high group(HD,6.67Mg kg1 BW d),middle group(MD,3.33 Mg kg1 BW d')and low group(LD,1.67 Mg kg1 BW·d1 three groups).Except CK,other groups were drunk 0.24%Pb(AC)»in which rats were lled with functionalcompound recipe liquid to eliminate lead and DSMA was added to positive group(PD).On the 20th day,the blood was collectedfrom the tail.on the 40th day,the whole blood was collected from eyeball.After executed,liver and blood were collected to determinethe content of lead and calcium.Results showed that lead contents in blood and liver of three dosage groups obviously decreasedcompared with ND and there was signi cant difference between any two groups of three dosage groups(Pc0.01).Meanwhile,thecalcium concentration increased in three dosage groups.It is concluded that the fumctional compound recipe liquid of eliminating leadhas the evident function of eliminating lead and can promote calcium absorption.
文摘Hundreds of children died in 2010 due to suspected lead poisoning from mining sources in Zamfara State among epidemiological concerns. Evaluating ecological and human health risks of heavy metals levels in sampled food crops harvested near two abandoned Lead-Zinc mining sites at Logo Benue State is crucial. <i>Abelmoschus esculentus</i>, <i>Carica papaya</i>, <i>Manihot esculenta</i>, and <i>Zea mays</i> were sampled, prepared, and analyzed for four heavy metals using the Atomic Absorption Spectrophotometric method. The mean data from the analysis of variance was subjected to ecological and health risk models. Pb means value ranged from <i>Carica papaya</i> Peel 0.46 ± 0.011 mg/kg to 1.30 ± 0.01 mg/kg in <i>Zea mays</i> seed. Zn was highest in <i>Carica papaya</i> flesh 0.50 ± 0.01 mg/kg, and lowest in <i>Manihot esculenta</i> peels and its flesh 0.12 ± 0.000 mg/kg. Hg and Cd were below detectable levels. <i>Zea mays</i> <i>seeds</i> (1.001) had the highest Pd bioaccumulation factor. BAF of zinc and ecological indices were <1. Daily Intake of Metals were all <1, however, Hazard Quotient (HQ) of Pb was ≥1 in <i>Manihot esculenta</i> flesh 1.143 and Zea mays at 1714. Cancer Risks were within permissible range (10<sup>-4</sup> - 10<sup>-6</sup>). Health Risk result indicates communities around the mining area may be at risk of lead poisoning therefore due to high contamination of samples, routine checks on heavy metals especially lead is recommended to prevent excessive bioaccumulation in the body.
文摘The use of lead in ammunition for hunting exposes waterfowl to lead poisoning (plumbism) by accidental consumption of shotgun pellets. To test this hypothesis we sampled 18 liver tissue samples of Snow Goose (Chen caerulescens) collected during the 2012-2013 hunting season in a wetland near the city of Durango, Mexico. We quantified liver lead levels using an atomic absorption spectrophotometer and portions of liver were fixed and stained for their histological study. Average lead concentration (in dry weight) were under the normal range (mean = 0.73 ± 0.2, standard error) which do not represent any risk of poisoning. Liver tissue injuries were not observed in the histopathological analysis, suggesting no reaction to a xenobiotic agent such as lead. Gastrointestinal content analysis showed lead pellet in the gizzard of one individual, but we could not find a relationship between pellet ingestion and lead concentration in the liver. Although the results did not provide evidences of lethal or sublethal effects caused by lead poisoning, they show a possible risk due to the presence of lead pellets in the digestive tract.
