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The organochlorine insecticide endosulfan (ES) is widely used despite its high toxicity to fish (96-h LC(50) median value of 2.6 μg L(-1)). This study aimed to assess the acute toxicity, histological and physiological parameters after exposure to 0; 0.25; 1; 2; 3; 4 and 16 μg L(-1) ES for 96 h under semi-static conditions in a freshwater perciform fish, Cichlasoma dimerus. Prior to death, fish exhibited behavior indicative of neurotoxicity. No difference was found in brain AChE activity. A decrease in erythrocyte mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration in exposed fish suggests a state of anemia. Histological alterations observed in exposed fish included hyperplasia of the interlamellar epithelium, blood congestion in secondary lamellae, and mucous cells hyperplasia and hypertrophy in gills; pycnotic nuclei and hydropic degeneration in liver; testicular damage. These moderate pathological responses in major organs could become crucial during reproduction and under prolonged exposure periods., (Copyright © 2011 Elsevier Inc. All rights reserved.)

In this study, some biochemical features and the extent of inhibition induced by the organophosphorous pesticide azinphos-methyl on the cholinesterase (ChE) activity present in whole soft tissue of two freshwater invertebrate species, the gastropod Biomphalaria glabrata and the oligochaete Lumbriculus variegatus were investigated. Both invertebrate organisms presented marked differences in ChE activity, type of enzymes and subcellular location. Acetylthiocholine was the substrate preferred by B. glabrata ChE. The enzyme activity was located preferentially in the supernatant of 11,000 x g centrifugation and was inhibited by increasing concentrations of substrate but not by iso-OMPA. Results showed that there were progressive inhibitions of the enzyme activity, with values 21%, 59%, 72%, 76%, and 82% lower than the control at levels of 1, 10, 50, 100 and 1000 microM of eserine, respectively. In contrast, L. variegatus ChE activity was distributed both in the supernatant and pellet fractions, with values approximately 6 and 20 times higher than B. glabrata, respectively. Studies with butyrylthiocholine and iso-OMPA suggested that about 72% of the activity corresponded to butyrylcholinesterase. A strong enzyme inhibition (88-94%) was found at low eserine concentrations (1-10 microM). ChE activity from L. variegatus and B. glabrata was inhibited by in vivo exposure to azinphos-methyl suggesting that both species can form the oxon derivative of this pesticide. However, both invertebrate species showed a very different susceptibility to the insecticide. The NOEC and EIC50 values were 500 and 1000 times lower for L. variegatus than for B. glabrata, reflecting that the oligochaetes were much more sensitive organisms. A different pattern was also observed for the recovery of the enzymatic activity when the organisms were transferred to clean water. The recuperation process was faster for the oligochaetes than for the gastropods. Mortality was not observed in either of the experimental conditions assayed, not even at concentrations that induced 90% of ChE inhibition. The differences in substrate specificity, sensitivity to inhibitors, and subcellular location between the ChEs of B. glabrata and L. variegatus could be the main factors contributing to the differential susceptibility to azinphos-methyl ChE inhibition found in the present study.

Objective: To evaluate the effectiveness of an education intervention in a summer camp setting on knowledge, attitudes, and health beliefs regarding metabolic control of phenylketonuria and dietary compliance., Design: An observational study of a weeklong metabolic camp for adolescent girls with phenylketonuria (PKU) who were followed up over the course of 1 year. Observations also were made in 3 subsequent years of camp., Intervention: The camp experience consisted of diet and disease education, sessions on reproductive development, and recreation. Group discussions on attitudes and perceptions about PKU related to dietary compliance were held with nutritionists and a pediatric psychologist., Outcome Measures: Biochemical and psychological data were collected on the first and last days of the camp to assess short-term effects of the intervention, then at quarterly intervals during the year to determine the long-term impact of the camp. Precamp and Postcamp plasma amino acid data for the subsequent 3 years were also collected., Subjects/setting: Analyses were based on 13 adolescent girls with PKU in the first year of a camp at Emory University in Atlanta, Ga, and compared with data from 11 additional campers enrolled the second year, 8 in the third year, and 7 in the fourth year. Mean age +/- standard deviation of first-year campers was 13 +/- 2 years, mean IQ +/- standard deviation was 98 +/- 16, and 9 of 13 girls had menstruated., Statistical Analyses Performed: Short-term effects of the intervention were computed by comparing mean levels of response from the baseline period to those from the last day of camp using t tests for dependent samples. Repeated-measures analysis of variance was used to assess the long-term effects of the camp experience over the course of a year at regular quarterly intervals., Results: Short-term effects of the education intervention were significant reductions in dietary phenylalanine intake, plasma phenylalanine levels, and perceived isolation. However, these effects progressively returned to baseline levels over the course of a year. The significant short- and long-term effects of increased knowledge of diet and disease persisted throughout the study period., Applications/conclusions: Short-term effects of the education intervention resulted in improved metabolic control associated with improved attitudes, increased knowledge of diet and disease, increased perceived support, and decreased barriers to dietary compliance in a camp setting.

Purpose: This study evaluates a genotype/phenotype relationship between developmental verbal dyspraxia (DVD) and the common, missense mutation of the galactose-1-phosphate uridyltransferase gene, Q188R, in patients with classic galactosemia (G/G)., Methods: As part of this study, we devised a questionnaire for "speech problems" to be completed by the patient\'s clinician. To validate the questionnaire and determine its accuracy in detecting DVD, we analyzed questionnaire responses for 21 patients by testing them independently and directly for DVD through a speech pathologist blinded to the patients' genotype., Results: We found that the questionnaire had a sensitivity of 0.56 and a specificity of 0.75. We then calculated the prevalence of DVD for a larger set of 113 patients with G/G galactosemia whose biochemical phenotype, molecular genotypes, and clinical status were known. The prevalence of "speech problems" from raw data were 50 of 113 (44.2%). After adjusting for misclassification, 43 (38.1%) were classified as cases of DVD. Using multivariate, logistic, regression analyses we found a significant interaction between genotype and mean red blood cell (RBC) galactose-1-phosphate (Gal-1-P). When corrected, using mean RBC Gal-1-P < h 3.28 mg%, the Q188R/Q188R genotype was the best predictor of DVD. There was a significant risk (odds ratio = 9.6, p = 0.0504) of having DVD associated with homozygosity for Q188R compared with other genotypes., Conclusions: We conclude that homozygosity for Q188R mutations in the GALT gene is a significant risk factor for DVD. However, poor metabolic control obviates this relationship as indicated by RBC Gal-1-P greater than 3.28 mg%.