Evaluation of neurobehavioral abnormalities and immunotoxicity in response to oral imidacloprid exposure in domestic chickens (Gallus gallus domesticus)

ABSTRACT

Domestic chickens (Gallus gallus domesticus) were exposed to imidacloprid by gavage once daily for 7 consecutive days at 0, 0.03, 0.34, 3.42, 10.25, and 15.5 mg/kg/day (n = 20 per group; 5 6-week-old males, 5 6-week-old females, 5 9-week-old males, and 5 9-week-old females). The severity and duration of neurobehavioral abnormalities were recorded. Components of the innate and adaptive immune system were assessed with 7 standard functional assays. Temporary neurobehavioral abnormalities were observed in a dose-dependent manner, including muscle tremors, ataxia, and depressed mentation. Based upon mean clinical severity scores, the no observed adverse effect level (NOAEL) was 3.42 mg/kg/day, and the lowest observed adverse effect level (LOAEL) was 10.25 mg/kg/day. The effective dose value for the presence of any neurobehavioral abnormalities in 50% of the test group (ED₅₀) was 4.62 ± 0.98 mg/kg/day. The ED₅₀ for an adjusted score that included both severity and duration of neurobehavioral abnormalities was 11.24 ± 9.33 mg/kg/day. These ED₅₀ values are equivalent to a 1 kg bird ingesting 29 or 70 imidacloprid treated soybean seeds respectively. Immunotoxicity was not documented, possible causes include the assays were insensitive, relevant immune functions were not examined, or imidacloprid is not immunotoxic at this dosing schedule in this species. Neurobehavioral abnormalities were a more sensitive indicator of the sublethal effects of imidacloprid than immunotoxicity.     

SAS amplification in soft tissue sarcomas.

Gene amplification is an important mechanism of increased gene expression in a number of human solid tumors. We have recently identified and cloned sequences from a novel DNA amplification unit in malignant fibrous histiocytoma. The amplified sequences are derived from chromosome 12q13-14 and encode a gene designated SAS (sarcoma amplified sequence). In the present study, a series of soft tissue sarcomas was studied to characterize further the phenomenon of SAS amplification. Seven of 22 (32%) malignant fibrous histiocytomas and three liposarcomas contained SAS amplification. Strikingly, all of the tumors with SAS amplification occurred in central sites (i.e., in the abdominal or inguinal regions) rather than in the extremities (i.e., in the arms of legs). These observations demonstrate that SAS amplification occurs with a significant frequency in mesenchymal tumors and is particularly associated with abdominal disease.     

Glutathione ester protects against hydroxynonenal-induced loss of auditory hair cells.

OBJECTIVE: Test the ability of glutathione monoethyl ester (GSH(e)) to protect auditory hair cells against the ototoxic effects of 4-hydroxy-2,3-nonenal (HNE). STUDY DESIGN AND SETTING: Organ of Corti explants were either untreated or treated with one of a series of four concentrations of GSH(e) for one day, then exposed to HNE. Counts of FITC-phalloidin-labeled hair cells determined both HNE ototoxicity and GSH(e) otoprotection. RESULTS: HNE was toxic to hair cells at physiologically relevant levels, eg, 400 muM, and GSH(e) provided a significant level of protection against HNE ototoxicity (P < 0.05) at all levels tested, ie, 1.16 to 9.3 mM. CONCLUSION: GSH(e) protects auditory hair cells from damage and loss initiated by a naturally occurring ototoxic molecule, ie, HNE (a by-product of oxidative stress). SIGNIFICANCE: Treatment with GSH(e) may be an effective therapy to protect the cochlea against the adverse effects of traumas (eg, electrode insertion) that generate oxidative stress.     

Validity and reliability of the infant Behavioral Summarized Evaluation (IBSE): A rating scale for the assessment of young children with autism and developmental disorders

The Infant Behavioral Summarized Evaluation (IBSE) is a rating scale adapted from the Behavioral Summarized Evaluation (BSE) and specifically related to the assessment of behaviors of young children having autistic disorders. Content validity and reliability studies described in the paper were made from behavior ratings of videotapes for 89 children aged from 6 to 48 months. Results show a significant group of 19 items including some characteristic early autistic behaviors (communicative and social abnormalities) and some that are less commonly described in the syndrome (attentional, perceptive, and adaptive disorders). The value of the use of this scale for clinicians and professionals involved in behavioral evaluations and treatment of young children with developmental disorders and the necessity for further psychometric investigations are discussed.This study was supported by INSERM U.316 Nervous System from the Foetus to the Child. Development, Circulation, Metabolism, L. Pourcelot, INSERM, Network INSERM No. 489001, Grant INSERM No. 911182 (D. Savrage) No. 911008 (L. Hameury) MRT. No. 9906 Fondation Langlois. Gratitude is expressed to Professor G. Lelord who initiated and supervised this study. The authors thank Professor J. Fermanian, Department of Biostatistics, CHU Necker, Paris, for his helpful suggestions and assistance. They also thank Dr. Larmande, Dr. Leddet, Dr. Glorion, and Dr. Garreau for their medical participation in the study and C. Richard, C. Fillatre, J. Rabant, and F. Etourneau for the psychological assessments of children. Special thanks to G. Calzas, M. Barré, A. Lardeux, and D. Lioret for their technical assistance.     

Mutation A1298C of methylenetetrahydrofolate reductase: risk for early coronary disease not associated with hyperhomocysteinemia

Diminished activity of 5,10 methylenetetrahydrofolate reductase (MTHFR), a regulatory enzyme of homocysteine metabolism, may predispose to coronary artery disease (CAD). In a case-control study we determined the prevalence of two common MTHFR polymorphisms, C677T and A1298C, in 161 male patients under the age of 50 years with angiographically documented CAD and compared it to that in 211 healthy controls. Genotyping was also performed in a random population sample, consisting of 149 men and 121 women at an average age of 40 years. The studied group had classic risk factors of atherosclerosis but did not differ in fasting plasma homocysteine, folic acid, and vitamin B12 levels in either the control group or population sample. The frequency of the 1298C allele was significantly higher in CAD (0.304) than in controls (0.199) or the population sample (0.235). Allele 1298C showed a significant association with early-onset CAD both in homozygotes and in heterozygous carriers. These findings were further supported by comparisons with the population sample. Homozygosity for allele 677T showed a tendency to associate with CAD. Allele 1298C of MTHFR is associated with early-onset CAD (carriers- RR = 1.71, 95% CI: 1.13-2.59; homozygotes- RR = 3.09, 95% CI: 1.36-7.02), even when blood homocysteine levels are not elevated.