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Biomedical subjects

P Acosta

Publications and source records attributed to P Acosta.

8 recordsLinked to original sources
PubMed2005

Daily rhythms in blood and milk lead toxicokinetics following intravenous administration of lead acetate to dairy cows in summer.

The objective of this study was to investigate circadian variations of blood and milk lead toxicokinetics in dairy cows in summer. Twenty lactating Holstein animals were randomly assigned to four treatments corresponding to different hours after onset of light (HALO): 2, 8, 14, and 20. Cows received a single intravenous administration of 2.5 mg/kg lead as lead acetate. Blood and milk samples were taken and analyzed by atomic absorption spectrophotometry. For each toxicokinetic parameter, a one-way analysis of variance (ANOVA) was performed to outline the existence of daily variations. Significant blood differences as a function of HALO were found for the hybrid constant of distribution (alpha), hybrid constant of elimination (beta), elimination half-life (t(1/2)beta), area under the curve (AUC), volume of distribution at steady state (V(ss)) and clearance (Cl(B)) (p<0.05). Half-life of elimination presented two peaks at 2 and 14 HALO. Milk data showed significant differences for maximum concentration and AUC (p<0.05). The ratio AUC(milk)/AUC(blood) was utilized to estimate penetration of lead in milk. It differed significantly throughout the day (p<0.05). Milk data for the significant parameters could be fitted to circadian rhythms. No circadian rhythms were detected in blood parameters or in the ratio AUC(milk)/AUC(blood).

Animals↗
PubMed2000

Acute and oral subchronic toxicity of D-003 in rats.

D-003 is a mixture of higher aliphatic primary acids purified from sugar cane wax (Saccharum officinarum) with cholesterol-lowering and antiplatelet effects experimentally proven. The present work reports the results of two studies investigating the acute and subchronic oral toxicity of D-003 in rats. Oral acute toxicity of D-003 (2000 mg/kg) was investigated according to the Acute Toxic Class (ATC) method (an alternative for the classical LD(50) test), which was performed in Wistar rats. The results obtained in this study defined D-003 oral acute toxicity as unclassified. In the subchronic study, rats of both sexes were orally treated with D-003 at 50, 200 and 1250 mg/kg for 90 days. At this time, animals were sacrificed. No evidence of treatment-related toxicity was detected during the study. Thus, data analysis of body weight gain, food consumption, clinical observations, blood biochemical, haematology, organ weight ratios and histopathological findings did not show significant differences between control and treated groups. It is concluded that D-003 orally administered to rats was safe and that no drug-related toxicity was detected even at the highest doses investigated in both acute (2000 mg/kg) and subchronic (1250 mg/kg) studies.

Administration, Oral↗
PubMed2000

The International Collaborative Study of Maternal Phenylketonuria: status report 1998.

UNLABELLED: The Maternal Phenylketonuria Study began in 1984 and during the intervening years, 572 pregnancies in hyperphenylalaninemic women and 99 controls and their outcomes have been evaluated. Among hyperphenylalaninemic women who delivered a live infant, only 15.9% were treated and in metabolic control preconceptually, however, another 18.4% were in control by 10 weeks. Compared to the results reported by Lenke and Levy in 1980, there is a marked improvement in outcome with treatment. Microcephaly was unusual in preconceptually treated pregnancies with well controlled phenylalanine restricted diets. Even in pregnancies that established control after conception but before the 8th week, congenital heart disease did not occur in the offspring, however, it did occur in 12% of pregnancies not achieving control until after 10 weeks of pregnancy. CONCLUSION: The recommended level of blood phenylalanine during pregnancy is 120-360 mumol/l. Best results were obtained by close cooperation between the attending obstetrician and a metabolic team experienced in the care of persons with phenylketonuria.

Adult↗
PubMed1988

Blood phenylalanine levels and intelligence of 10-year-old children with PKU in the National Collaborative Study.

Dietary intakes and blood phenylalanine levels of 125 10-year-old children with PKU are reported. Of those patients, 59 discontinued the special diet at 6 years, 16 discontinued at 8 years, 5 discontinued at 6 years but returned to the diet at 8 1/2 years, and 45 continued the diet to 10 years. Phenylalanine intake was determined by 2-day diet records. Blood phenylalanine concentrations revealed a lack of clear distinction between the diet groups; therefore, regression analysis was performed on the group as a whole. The analyses revealed significant relationships between blood phenylalanine levels from ages 6 to 10 years and each of the cognitive outcome variables, after the influences of parental IQ and the age at which treatment was initiated were controlled for. Intelligence test scores were also related to phenylalanine levels between ages 3 1/2 and 5 1/2 years. The findings suggest that dietary restriction of phenylalanine should continue in patients with PKU through at least 10 years of age.

Child↗
PubMed1976

A computerized procedure for estimating nutrient intake.

A procedure was devised for computing intake in terms of calories, total protein, phenylalanine, carbohydrate, and fat. The procedure used a magnetic tape containing 3,122 numbered food items. The nutrient composition of each food was reported for 100 g of the edible portion of the food. In addition, diet diaries were prepared in which the foods eaten during the preceding 24-hr period, the code for each food corresponding to the number for the same item on the magnetic tape, and the number of units of each food eaten were recorded. A computer program then was written that calculated the amounts of intake per day for each nutrient. Application of the procedure for 42 consecutive days on the daily diet records of 43 adult carriers of the phenylalanine hydroxylase enzyme formed the data base used to determine if aspartame significantly increased levels of phenylalanine in the blood. Adaptations of the procedure permit calculations of intake for periods from 1 to 30 days and analyses of additional nutrients including calcium, phosphorous, iron, vitamin A, thiamine, riboflavin, niacin, and ascorbic acid.

Computers↗