Aminopyrine demethylation kinetics. Use of metabolite exhalation rates as an index of enhanced mixed-function oxidase activity in vivo.

The usefulness of determining aminopyrine demethylation kinetics via monitoring of metabolite exhalation rats had been assessed. In rats receiving [N-dimethyl-14C]aminopyrine, a biexponential decline in the 14CO2 exhalation rate is apparent when monitoring is continued over a 5 to 6-hr period. Both the fast phase (representing the first demethylation) and the slower phase (representing the second demethylation) are markedly influenced by phenobarbital and promethazine pretreatment.

Polymyositis associated with Hodgkin's disease.

A patient is reported who presented with severe polymyositis and pulmonary collapse with infection. Investigations failed to confirm an underlying bronchial carcinoma but post-mortem examination revealed unsuspected Hodgkin's disease. The authors wish to draw attention to the rare but important association between polymyositis and treatable lymphomas.

Quantification of naphthyl conjugates. Comparison of high-performance liquid chromatography and selective enzyme hydrolysis methods.

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Influence of phenobarbitone pretreatment on disposition of amidopyrine and its metabolites in rat.

Plasma concentration-time profiles for amidopyrine and its primary desmethyl metabolite have been determined in control rats and in rats pretreated with phenobarbitone. The kinetics of both compounds indicate enhanced clearance following pretreatment. Metabolite excretion in urine, bile and breath support the plasma data.

Prevalence of mandibular dysfunction in young adults.

A sample of students (739) were questioned and examined for symptoms and signs associated with mandibular dysfunction. The most frequently mentioned symptoms were headache, TMJ sounds, and pain in the face or neck. No significant differences were found between men and women with symptoms other than headache.

Four-component polarization measurement of lidar atmospheric scattering.

Measurements of the backscattering from the lower atmosphere of linearly polarized ruby lidar pulses at 694 nm are described. A four-channel receiver provides simultaneous measurements of the four components of the Stokes vector of the scattered radiation. These data are used to obtain information on the polarization state of the scattering and its dependence on atmospheric conditions.

Effects of smoking on free recall and organization.

Habitual smokers smoked either nicotine-free cigarettes or cigarettes containing a known amount of nicotine and then engaged in a free-recall task. Nicotine subjects recalled significantly fewer words on a 75-item list during three successive trials of immediate recall than did nicotine-free subjects. Contrary to expectations, the superiority of the nonnicotine group persisted over two days.

Epinephrine absorption from retraction cord: a study in dogs.

This report re-opens the question of epinephrine absorption from gingival retraction cord during fixed prosthodontic impression procedures. The conflicting evidence exposed by this and other studies is probably related to the experimental models utilized. Some suggestions for further investigation are given.

Effect of activated charcoal on acetaminophen absorption.

Acetaminophen intoxication can cause hepatic, renal, and myocardial necrosis which is often fatal. These lesions develop very rapidly, perhaps during the first pass of the drug through the liver. In case of acute ingestion of an overdose it is therefore essential to employ measures for reducing the absorption of acetaminophen.