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Biomedical subjects

B MacGibbon

Publications and source records attributed to B MacGibbon.

4 recordsLinked to original sources
PubMed1979

The distorted shell method for clustering for syndrome classification.

Syndrome classification may be described as the arrangement of individuals into groups on the basis of their phenotypic resemblance. This paper describes how phenotypic resemblance may be quantified and demonstrates a numerical method called distorted shell clustering, which isolates groups of phenotypically similar individuals representing syndromes. This new method takes into consideration apparent biological properties of syndromes. It allows for overlapping phenotypes between syndromes, and differing character association and variability within syndromes. This method is compared to four other clustering methods by using suspects for a syndrome of known etiology (Down syndrome). The numerical results based on the phenotype then can be compared with the actual diagnosis. Only the distorted shell method classifies patients, without error, into two major clusters: the Down and the non-Down, while maintaining a high level of efficiency.

Disease↗
PubMed1978

Some properties of the specific androgen-binding activities in cultured human genital skin fibroblasts.

Specific 5 alpha-dihydrotestosterone (DHT)-binding activity in the cytosol (C) and 0.4 M KCl-extractable nuclear fraction (N) of cultured human fibroblast cell strains developed from preputial (n = 12) and labium majus (n = 12) skin were analyzed by gel exclusion chromatography, sucrose gradient sedimentation, and thermostability. Both fractions had activities that were excluded from Sephacryl S-200 columns; another component (mol wt, 20,000) was present in the N fraction. The C was more thermostable than a homologous N activity, and addition to the former of KCl to 0.4 M had no effect. There was large, overlapping variation in thermostability of the C and N activities among strains from either site, sister strains developed from a single skin biopsy, and even among serial subcultures within a strain; likewise, the variable sedimentability of the C (4-7S) and N (3.2-5.9S) activities prevented their consistent discrimination. Each type of variation occurred despite excellent intraexperimental replication. The thermostability of a given N activity varied directly with its sedimentation coefficient. By cluster analysis, the data relating thermostability of a given N activity with the percentage of 0.4 M KCl-resistant nuclear activity segregated into two populations; within each population these two measurements were related inversely. We suggest that these coordinate behaviors of the N activity reflect intrinsic properties of the androgen-receptor system in normal genital skin fibroblasts which may be useful for defining qualitative aberrations of the system in receptor-positive forms of congenital androgen insensitivity.

Adolescent↗
PubMedDate not supplied

A radiologic survey of various configurations of the lumbar spine.

This paper reports an investigation to determine whether or not human spine configurations can be categorized into types by which one could predict the possibility of disablement at one specific level more than another. Configurations of the lumbar spine, the shape of the lower two lumbar discs, the anterior and posterior heights of discs, the sizes of the transverse processes of L4-5, the presence or absence of rudimentery ribs, and the presence of transitional vertebrae were studied in roentgenograms of 554 subjects. They concluded that the probable criteria for development of L4-5 degeneration were 1) high intercrestal line passing through the upper half of L4, 2) long transverse process on L5, 3) rudimentary rib, and 4) transitional vertebra. Criteria for development of L5-S1 degeneration were 1) intercrestal line passing through the body of L5, 2) short transverse process on L5, 3) no rudimentary rib, 4) no transitional vertebrae. A high intercrestal line and long transverse process probably act as antitorsional devices protecting the L5-S1 disc; hence the likelihood of degeneration at L4-5 is increased.

Adult↗