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Biomedical subjects

E R Hawkins

Publications and source records attributed to E R Hawkins.

8 recordsLinked to original sources

Discriminative stimulus effects of nalbuphine in nontreated and morphine-treated pigeons.

In the present study, the stimulus effects of the low efficacy agonist nalbuphine were examined under two conditions: nontreated and morphine treated. In the first experiment, five pigeons were trained to discriminate among 3.2 mg/kg morphine, 5.6 mg/kg nalbuphine, and saline. Nalbuphine produced nalbuphine-like responding. Low doses of morphine produced nalbuphine-like responding, whereas high doses produced morphine-like responding. Naltrexone produced saline-like responding and reversed the stimulus effects produced by the training doses of morphine and nalbuphine. Five different pigeons were treated daily with 10 mg/kg morphine (i.m.) and trained 6 h later to discriminate among 10 mg/kg morphine, 1.0 mg/kg nalbuphine and saline. In these pigeons, morphine produced morphine-like responding and nalbuphine produced nalbuphine-like responding. Morphine abstinence produced nalbuphine-like responding that was reversed by morphine. Additionally, naltrexone produced nalbuphine-like responding. These data suggest that the discrimination between morphine and nalbuphine in the nontreated and morphine-treated pigeons may be based on the relative efficacy differences between morphine, a higher efficacy mu-agonist, and nalbuphine a lower efficacy mu-agonist.

Analgesics, Opioid↗

Occupational asthma in salbutamol process workers.

Occupational asthma after exposure to salbutamol in the pharmaceutical industry has not been previously reported. The occurrence of occupational asthma is described in two pharmaceutical process workers who were likely to have inhaled doses appreciably in excess of the therapeutic dose range. The findings do not lead to an unequivocal conclusion on the mechanism of the asthma but it was probably a pharmacological consequence of high exposure.

Adult↗

Laboratory animal allergy in a pharmaceutical company.

A cross sectional survey was carried out on 138 workers exposed to laboratory animals. Sixty (44%) had symptoms in a self completed questionnaire that were consistent with laboratory animal allergy (LAA) of whom 15 (11%) had chest symptoms. There was a positive skin prick test to one or more animal urine extracts (rat, mouse, guinea pig, rabbit) in 13% and 38% had a positive radioallergosorbent test to urine extract. LAA chest symptoms were almost five times more common in atopic than non-atopic subjects (who were distinguished by skin test response to common, non-animal aeroallergens). A positive skin test to animal urine was associated with LAA chest symptoms and with atopy. Nose, eye, or skin symptoms without chest symptoms were not associated with atopy. There was an inverse relation between duration of employment at the firm and LAA chest symptoms, suggesting selection of affected people out of employment with animals.

Adult↗

Smoking, atopy, and laboratory animal allergy.

This study examined data from three cross sectional surveys of 296 laboratory workers exposed to small mammals. Four indices of laboratory animal allergy were studied: symptoms suggestive of occupational asthma, symptoms suggestive of any occupational allergy, skin weals to animal urine extracts, and serum binding in radioallergosorbent tests with urine extracts. Pooled data from the three surveys showed an association between smoking and all indices except radioallergosorbent tests; the association was significant for symptoms of occupational asthma. One of the three surveys consistently showed a stronger association of allergy indices with smoking than with atopy (defined on skin tests with non-animal aeroallergens). Associations with smoking persisted after stratifying by atopic status, suggesting that smoking may be a risk factor for laboratory animal allergy.

Adult↗

Occupational allergy to locusts: an investigation of the sources of the allergen.

Allergic symptoms occur commonly in subjects working closely with locusts and are associated with specific IgE antibody. Extracts of intact locusts (Schistocerca gregaria and Locusta migratoria) were used to identify specific IgE antibody, to define the major allergens of the locust and their sources, and to estimate aeroallergen concentration in the working environment. With questionnaire, skin prick tests, and specific IgE measurements, 35 individuals, working in a research center, were surveyed. Of the 15 currently exposed individuals, contact with locusts provoked asthma, rhinitis, and contact urticaria in five, rhinitis and urticaria in three, and rhinitis alone in one individual. Symptoms provoked by locusts and skin test reactions to locust extracts were associated with specific IgE antibody in the serum. The "immunoblot" technique demonstrated the presence of multiple allergens in the locust extracts of approximately 68, 66, 54, 43, 37, 29, and 18 K daltons molecular weight. Locust antigen was identified in the atmosphere by means of an immunochemical method involving elution of high-volume air-sampler filters exposed in the locust breeding room and analysis of eluate allergen content by RAST-inhibition assays. Logit transformation of RAST-inhibition lines demonstrated that the filter extract shared a common slope with the locust extract and with an extract of locust gut. This gut extract also shared a common slope with extracts of locust feces and peritrophic membrane. The major source of allergen appears to be the peritrophic membrane that is present in the gut and is excreted surrounding the feces.

Allergens↗