Biomedical subjects

P S Herman

Publications and source records attributed to P S Herman.

At least 19 recordsLinked to original sources

PubMed1992

Relative stabilities of nitrenium ions derived from polycyclic aromatic amines. Relationship to mutagenicity.

The relative energetics of arylamine N-hydroxylation and N-O heterolysis (ArNH2----ArNHOH----ArNH+) for condensed systems of two, three and four rings were calculated using semiempirical AM1 molecular orbital theory. The overall thermodynamics of N-hydroxylation were almost insensitive to the structure of the amine while differences in the energetics of nitrenium ion formation varied from 0 to 35 kcal mol-1. Limited correlations between the latter and the experimental TA98 and TA100 mutagenicities of the amines are presented.

Amines↗

PubMed1989

Punctate porokeratotic keratoderma.

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Humans↗

PubMed1988

Colonic hamartomas in tuberous sclerosis.

Twelve patients, 5 from the same family, diagnosed consecutively to suffer from tuberous sclerosis were investigated for gastrointestinal polyps. Six patients had no clinical neurologic involvement. Nine had colonic polyps: in 5 patients, these were hamartomas, in 3 patients adenomatous polyps, and the ninth patient had hamartomas and adenomatous and villoglandular polyps. Hamartomatous polyps were identical to those found in the Peutz-Jeghers syndrome. However, in 1 patient they included neural structures and in another there were angiomatous and adipous structures in addition to colitis cystica profunda. Two patients with hamartomatous polyps had normal intelligence and no clinical neurologic symptoms. The evaluation of one kindred revealed the association of hamartomatous polyps of the colon with forme fruste of tuberous sclerosis in different members, but none had the typical disease. Tuberous sclerosis should thus be considered in the differential diagnosis of hamartomatous colonic polyps. Conversely, colonic endoscopy may be a useful adjunctive test in the diagnosis of tuberous sclerosis, particularly in the incomplete varieties of disease.

Adolescent↗

PubMed1988

Punctuate porokeratotic keratoderma.

Two unrelated patients had numerous palmoplantar "music box spine" keratotic plugs and pits of 11 and 13 years' duration. Histologic examination revealed a compact column of parakeratosis resembling that of a cornoid lamella of porokeratotic conditions. Ultrastructurally in clinically affected skin, the stratum corneum contained numerous variable-sized pyknotic nuclei, and cells in the stratum granulosum contained fewer keratohyalin granules. The ultrastructural findings differed from those of porokeratosis of Mibelli and disseminated superficial actinic porokeratosis. The proper nosologic designation should be punctuate porokeratotic keratoderma.

Aged↗

PubMed1978