Health, income, and activities of retired physicians.

Driven to retire mainly by changes in the health care delivery system, physicians nevertheless find it difficult to reduce their professional activities as they grow older. Retired physicians in a seven-county region of upstate New York were surveyed to discover how they were faring in retirement and to elicit information of possible value to doctors planning to retire. Good health and adequate income were the prime factors in successful retirement, along with active involvement in postretirement activities, especially nonmedical ones. Three quarters of respondents found annual incomes between $25,000 and $50,000 to be comfortable. All agreed that private investments must make up at least a third of this amount, supplementing Social Security, pensions, individual retirement accounts, and Keogh plan distributions. There was diversity of opinion on remaining active in medical affairs after retirement. A large majority of those who found retirement better than anticipated advised a clean break with medicine. Most of their colleagues who rated retirement about as expected or not as good as anticipated counseled continued involvement in professional activities.

Fluorescence and mass spectral evidence for the formation of benzo[a]pyrene anti-diol-epoxide-DNA and -hemoglobin adducts in humans.

Highly specific methods are required to detect and quantitate carcinogen-macromolecular adducts in humans who are exposed to complex mixtures of chemical carcinogens. High performance liquid chromatography and fluorescence spectroscopy have been used successfully to detect and identify residues of benzo[a]pyrene-7,10/8,9-tetrahydrotetrol (BP-7,10/8,9-tetrol) that were released upon mild acid hydrolysis of human DNA or hemoglobin. Synchronous fluorescence spectroscopy data indicate that levels of benzo[a]pyrene-diol-epoxide-DNA (BPDE-DNA) adducts as high as 1.54 fmol BPDE/micrograms DNA are formed (1 adduct in 5 million nucleotides) in peripheral blood lymphocytes of coke-oven workers; these data were subsequently corroborated by gas chromatography/mass spectroscopy single ion monitoring analysis (m/z 404+). Additionally, among lung cancer patients, 5 samples of tumor DNA were found to be negative and 1 of 4 samples of corresponding lung tissue was found to be positive. Extraction and purification of BP-7,10/8,9-tetrol from the hemoglobin of smokers suggested levels of bound carcinogen in excess of 1 ng BPDE/gm of hemoglobin. High performance liquid chromatography combined with synchronous fluorescence spectroscopy provides a highly specific method for the detection of covalently bound BP residues in both human hemoglobin and DNA.

Radioimmunoassay for chlorpromazine in plasma.

A radioimmunoassay for chlorpromazine in plasma is described. The antiserum was obtained by immunizing rabbits with a conjugate of bovine serum albumin and N-(2-carboxyethyl)desmethylchlorpromazine. It is specific for chlorpromazine and its minor active metabolite, N-desmethylchlorpromazine. Other known active or inactive chlorpromazine metabolites and other psychotropic drugs tested do not cross react with the antiserum. Less than 34 pg of the drug can be detected in 200 muL of plasma. As many as 100 samples can be processed in a day by one technician. Concentrations of chlorpromazine can be measured in 200-muL samples of plasma collected as late as 48 h after a single oral 25-mg dose.

Drug permeation through membranes V: interaction of diazepam with common excipients.

The effects of common tablet excipients on the permeation of diazepam through polydimethylsiloxane membranes and on the turnover time of goldfish were studied. The permeability coefficient decreased and the turnover time increased in the presence of talc, polysorbate 80, and, possibly, fumed silicon dioxide, but these parameters were unaffected by lactose, microcrystalline cellulose, and starch.