Developmental lead exposure: behavioral alterations in the short and long term.

Wistar dams were exposed to 500 ppm of Pb, as Pb acetate, or 660 ppm Na acetate in drinking water during pregnancy and lactation. Male pups at 23 (weaned) or 70 days (adult) of age were submitted to behavioral evaluation and Pb determination. The behaviors evaluated were: locomotor activity (open-field test), motor coordination (rotarod test), exploratory behavior (holeboard test), anxiety (elevated plus maze and social interaction tests), and learning and memory (shuttle box). Pb levels were measured in the blood and cerebral regions (hippocampus and striatum) of dams and pups. The results of the present report demonstrated that exposure to Pb during pregnancy and lactation induces in weaned pups hyperactivity, decreased exploratory behavior, and impairment of learning and memory. These alterations were observed at blood Pb levels in the range that may be attained in children chronically exposed to low levels of Pb (21+/-3 microg/dl). Regarding adults, the results demonstrated that the regimen of exposure adopted induces anxiety in these animals at nondetectable blood Pb levels.

Effect of L-arginine, dimercaptosuccinic acid (DMSA) and the association of L-arginine and DMSA on tissue lead mobilization and blood pressure level in plumbism.

Lead (Pb)-induced hypertension is characterized by an increase in reactive oxygen species (ROS) and a decrease in nitric oxide (NO). In the present study we evaluated the effect of L-arginine (NO precursor), dimercaptosuccinic acid (DMSA, a chelating agent and ROS scavenger), and the association of L-arginine/DMSA on tissue Pb mobilization and blood pressure levels in plumbism. Tissue Pb levels and blood pressure evolution were evaluated in rats exposed to: 1) Pb (750 ppm, in drinking water, for 70 days), 2) Pb plus water for 30 more days, 3) Pb plus DMSA (50 mg kg(-1) day(-1), p.o.), L-arginine (0.6%, in drinking water), and the combination of L-arginine/DMSA for 30 more days, and 4) their respective matching controls. Pb exposure increased Pb levels in the blood, liver, femur, kidney and aorta. Pb levels in tissues decreased after cessation of Pb administration, except in the aorta. These levels did not reach those observed in nonintoxicated rats. All treatments mobilized Pb from the kidney, femur and liver. Pb mobilization from the aorta was only effective with the L-arginine/DMSA treatment. Blood Pb concentrations in Pb-treated groups were not different from those of the Pb/water group. Pb increased blood pressure starting from the 5th week. L-arginine and DMSA treatments (4th week) and the combination of L-arginine/DMSA (3rd and 4th weeks) decreased blood pressure levels of intoxicated rats. These levels did not reach those of nonintoxicated rats. Treatment with L-arginine/DMSA was more effective than the isolated treatments in mobilizing Pb from tissues and in reducing the blood pressure of intoxicated rats.

Effect of L-arginine, dimercaptosuccinic acid (DMSA) and the association of L-arginine and DMSA on tissue lead mobilization and blood pressure level in plumbism

Lead (Pb)-induced hypertension is characterized by an increase in reactive oxygen species (ROS) and a decrease in nitric oxide (NO). In the present study we evaluated the effect of L-arginine (NO precursor), dimercaptosuccinic acid (DMSA, a chelating agent and ROS scavenger), and the association of L-arginine/DMSA on tissue Pb mobilization and blood pressure levels in plumbism. Tissue Pb levels and blood pressure evolution were evaluated in rats exposed to: 1) Pb (750 ppm, in drinking water, for 70 days), 2) Pb plus water for 30 more days, 3) Pb plus DMSA (50 mg kg-1 day-1, po), L-arginine (0.6 percent, in drinking water), and the combination of L-arginine/DMSA for 30 more days, and 4) their respective matching controls. Pb exposure increased Pb levels in the blood, liver, femur, kidney and aorta. Pb levels in tissues decreased after cessation of Pb administration, except in the aorta. These levels did not reach those observed in nonintoxicated rats. All treatments mobilized Pb from the kidney, femur and liver. Pb mobilization from the aorta was only effective with the L-arginine/DMSA treatment. Blood Pb concentrations in Pb-treated groups were not different from those of the Pb/water group. Pb increased blood pressure starting from the 5th week. L-arginine and DMSA treatments (4th week) and the combination of L-arginine/DMSA (3rd and 4th weeks) decreased blood pressure levels of intoxicated rats. These levels did not reach those of nonintoxicated rats. Treatment with L-arginine/DMSA was more effective than the isolated treatments in mobilizing Pb from tissues and in reducing the blood pressure of intoxicated rats

Efeitos do acetato de chumbro diluido e dinamizado (preparacao homeopatica) no tratamento do Saturnismo / Effects of diluted and dynamised lead acetate in the treatment of Saturnism

Os autores estudam o efeito do acetato de chumbo diluido e dinamizado (preparacao homeopatica) em ratos machos(Wistar) intoxicados por acetato de chumbo. Os resultados evidenciaram a eficacia da preparacao homeopatica comparavel a do EDTA na diminuicao da plumbemia.

Efeitos do acetato de chumbro diluido e dinamizado (preparacao homeopatica) no tratamento do Saturnismo / Effects of diluted and dynamised lead acetate in the treatment of Saturnism

Os autores estudam o efeito do acetato de chumbo diluido e dinamizado (preparacao homeopatica) em ratos machos(Wistar) intoxicados por acetato de chumbo. Os resultados evidenciaram a eficacia da preparacao homeopatica comparavel a do EDTA na diminuicao da plumbemia.(AU)

Clinical, cytogenetic and toxicological studies in rural workers exposed to pesticides in Botucatu, São Paulo, Brazil.

Pesticides can cause gene mutations and chromosomal aberrations in exposed individuals. We have investigated 24 workers exposed to pesticides. Clinical examinations and cytogenetic and toxicological tests were performed. Ten non-exposed individuals were used as controls. Toxicological dosages of copper, zinc and manganese (metals found in some pesticides), hepatic enzyme dosage (GOT, GPT, AR) and acetylcholinesterase activity were performed in 16 workers and 8 controls. In the exposed workers, the most relevant clinical symptoms were poor digestion with fullness sensation after meals, irritated eyes, headache and fasciculations. The exposed group showed significantly lower manganese dosage and acetylcholinesterase activity, and significantly higher levels of alkaline phosphatase. Cytogenetic studies showed significantly higher chromosomal aberrations in the exposed group compared to the control group. Although the workers used protection against the pesticide's fog, the results revealed that the workers were contaminated with the pesticides. Therefore, the cytogenetic, toxicological studies with clinical examination are necessary for monitoring workers who are exposed to pesticides in any situation.

Does magnesium chloride modify aldrin-induced neurotoxicity in rats?

Magnesium chloride (MgCl2) has been proposed for the treatment of seizures of different etiologies. The present study investigated the effect of MgCl2 on aldrin-induced seizures. Initially, 50 male rats received 60 mg aldrin/kg po and the effects were classified as muscular twitches, clonic convulsions or tonic-clonic convulsions. Another group of 40 rats dosed with 60 mg aldrin/kg po received 0, 4, 8, or 12 mg MgCl2/kg i.m. The percentage of tonic-clonic convulsant rats that resulted from MgCl2 treatment were 90% at 0 mg/kg, 50% at 4 mg/kg, 40% at 8 mg/kg and 20% at 12 mg MgCl2/kg. The percentage of survivors in the group receiving 12 mg MgCl2/kg was 80% while the control group had 20% survival. The clonic convulsions were not modified by MgCl2 treatment. Blood and brain concentrations of aldrin and dieldrin (metabolite of aldrin) did not differ among groups. The MgCl2 administration decreased the neuroexcitability induced by aldrin and increased survivability.

HPLC determination of flumethrin, deltamethrin, cypermethrin, and cyhalothrin residues in the milk and blood of lactating dairy cows.

A procedure to determine residue concentrations of synthetic pyrethroid insecticides (flumethrin, deltamethrin, cypermethrin and cyhalothrin) in the milk and blood of lactating dairy cows was developed. Extraction was performed with acetoritrile, n-hexane partitioning, and silica gel column cleanup with n-hexane and diethyl ether. Analysis was carried out by high-performance liquid chromatography and ultraviolet detection. Recovery of the four pyrethroids averaged 78 to 91% with a minimum detectable concentration of 0.001 mg/kg. The method was reproducible and sensitive.

Pyrethroid residues in milk and blood of dairy cows following single topical applications.

The presence of the pyrethroid insecticides flumethrin, deltamethrin, cypermethrin and cyhalothrin in milk and blood of 10 cows was determined after single dermal applications of recommended doses. Milk and blood samples were collected every 7 days over a 35-d period and analyzed by high-performance liquid chromatography. The highest residues in milk were found on day 28 for flumethrin and day 1 for deltamethrin, cypermethrin and cyhalothrin, while in blood the highest concentrations were present on day 28 for flumethrin and deltamethrin, the first day for cypermethrin, and day 14 for cyhalothrin.

Alcohol levels in cerebrospinal fluid and blood samples from patients under pathological conditions.

We measured alcohol levels by the Cordebard method in 148 CSF samples from individuals who had abstained from alcohol for at least 7 days prior to the beginning of the study. Each blood sample was accompanied by a CSF sample from the same patient. CSF samples found to be normal after analysis were used as controls. Mean alcohol concentration in blood did not differ significantly between the control group and the groups with altered CSF. The group with altered CSF had statistically higher alcohol levels in CSF than in blood. CSF lactate, glucose and protein levels were not correlated with alcohol level. The results suggest the presence of endogenous alcohol in the CSF, with levels increasing in the presence of pathological processes involving the nervous system.

Alcohol in cerebrospinal fluid (CSF) and alcoholism.

Alcohol levels were measured in 15 cerebrospinal fluid (CSF) samples and 14 blood samples from grade III and IV male alcoholic patients with signs of nervous system involvement, and compared with levels detected in 11 CSF samples and 11 blood samples from abstemious patients or patients with grade I or II alcoholism whose CSF had been found to be normal by routine analysis (controls). Among the alcoholic patients, alcohol levels were lower in the CSF than in blood, whereas the opposite was true for the controls. The possible mechanisms underlying this difference are discussed and the need for further study of this topic is emphasized.

Levels of organochlorine insecticides in milk of mothers from urban and rural areas of Botucatu, SP, Brazil.

PIP: The organochlorines DDT and hexachlorocyclohexane (HCH) were determined in mothers' milk in 21 women from rural towns and 21 from urban Botucatu, Sao Paulo, Brazil, and correlated with environmental factors such as prevalence of house spraying, smoking, and agricultural work. Extraction and gas chromatography methods were those published by the U.S. EPA. Average DDT levels in urban milk samples were 34.9 ppb, and in rural milk 16.5 ppb. Higher meat intake was probably a factor in higher urban yield. In contrast, rural levels of HCH were 46.3 ppb, compared to 14.4 ppb in urban mothers. DDT levels were consistently lower in women who had nursed 3 or more children, than those with 1 or 2. House spraying was related to higher DDT levels in rural areas only. DDT levels were much higher in women who smoked. HCH content was higher in younger women than older, and in houses that had been sprayed, especially in rural zones, where spraying programs are run by the public health authorities. Dieldrin was detected in only 3 urban samples.^ieng

Poisoning by chemical non-medicinal products in Brazil: clinical and laboratory findings in 132 patients.

One hundred and thirty-two patients with suspected exogenous intoxication were analysed according to clinical manifestation and toxicological results. Detection of toxic substances was performed in blood, urine and cerebrospinal fluid. The greatest occurrence of chronic exogenous intoxication was in males aged 21 to 50 years old. Peasants and industrial workers were the most affected. 70% of all patients showed neurological manifestations. There was clear predominance of central nervous system impairment associated with poisoning with herbicides and organophosphates.

Action of methoxyflurane on intraocular pressure (IOP) and acid-basic equilibrium in the dog.

MEthoxyflurane pulmonary inhalation administered to dogs, 2 ml/10kg/5 min, after 10 minutes caused a significant increase (13.3 mmHg) in intraocular pressure as well (6 mmHg) in venous pressure and a significant fall, of 23.3 mmHg, in arterial pressure and in respiratory frequency, of 3.2 per min and amplitude of 7.1 mm. On the other side, as acid-basic equilibrium alterations in blood, were observed a fall of 0.13 of pH and an increase of 18.3 mmHg of pCO2 and of 2.7 mEq/l of bicarbonate concentration.