Jan L. Willems

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The emetic and antiemetic effects of opioid agonists were studied in awake dogs. The mu-agonists morphine, fentanyl and methadone, in sedative doses, prevented the emetic response to apomorphine and copper sulphate; only morphine induced emesis, at doses lower than those required to prevent emesis. The delta-agonist [D-Ala2,Met5]enkephalinamide (DALA) and(More)
We measured in nine patients, poisoned by organophosphorus agents (ethyl parathion, ethyl and methyl parathion, dimethoate, or brompphos), erythrocyte and serum cholinesterase activities, and plasma concentrations of the organophosphorus agent. These patients were treated with pralidoxime methylsulphate (ContrathionR), administered as a bolus injection of(More)
Methyl parathion (20 mg · kg−1 intravenously and orally) and parathion (5 mg · kg−1 intravenously and 10 mg · kg−1 orally) were given to non-anesthetized dogs and the serum concentrations were followed in function of time. For both substances a low bioavailability after oral administration was found. In other dogs radioactivity was followed in urine after(More)
Lipophilic contaminants are present in the environment and bioaccumulate in the food chain. Therefore, their intake via animal fat of various sources was assessed for three age groups of the Flemish population, participating in a large biomonitoring program of the Flemish government. In total, 1636 adolescents (14-15 years), 1186 mothers (18-44 years), and(More)
1 Intravenous administration of apomorphine (1.25 to 20 microgram/kg) in the anaesthetized dog produced a dose-dependent decrease in blood pressure which was antagonized by haloperidol but not influenced by propranolol or atropine. 2 Intracarotid administration of apomorphine produced a systemic hypotension which was significantly smaller than that seen(More)
Food intake is one of the principal exposure routes of polybrominated diphenyl ethers (PBDEs) in humans. This study focuses on fish consumption as a PBDE exposure route. A probabilistic intake assessment of PBDEs and healthy long chain omega-3 PUFAs (LC n-3 PUFAs) was conducted for Belgian fish consumers in order to study the balance of the intake of LC n-3(More)
The toxicokinetics of methyl paraoxon, the active metabolite of the organophosphorus insecticide methyl parathion, were studied in non-anaesthetized dogs after intravenous (2.5 mg/kg) and oral (15 mg/kg) administration of methyl paraoxon. After intravenous administration, distribution and elimination occured very rapidly and using the data from 5 min(More)
To evaluate workers' exposure to dioxin-like substances (such as polychlorinated dibenzo-p-dioxins, dibenzofurans, and polychlorinated biphenyls), the authors used a chemical-activated luciferase gene expression (CALUX) assay to determine serum dioxin-like activity in five workers before and after two different cleaning-up activities inside a municipal(More)