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A R Poole

Publications and source records attributed to A R Poole.

212 records · Page 12Linked to original sources
PubMed1970

The locations of cathepsin activity and beta-glucuronidase in the Guerin T8 tumour.

Tumour homogenate fractions, isolated by differential centrifugation, were subfractionated by density-gradient centrifugation. Biochemical and electron microscopic analyses revealed that beta-glucuronidase and cathepsin activity were associated with a class (possibly two) of lysosomal particles of density greater than those of mitochondria and the endoplasmic reticulum. Lysosomes sedimented by low g forces were vacuolar, electron-dense, delineated by a unit membrane and about 0.2mum in diameter. beta-Glucuronidase was also apparently associated with ribosomes whereas cathepsin was bound in part to the endoplasmic reticulum. Catalase and glucose 6-phosphatase possessed slightly different density-gradient sedimentation profiles.

Animals↗
PubMedDate not supplied

Secretion and localization of cathepsin D in synovial tissues removed from rheumatoid and traumatized joints. An immunohistochemical study.

The proteinase cathepsin D which degrades proteoglycan was never demonstrated in extracellular sites in tissues from patients with traumatized meniscoid cartilage, either before or after culture with an antiserum to human cathepsin D. In contrast, in synovia (but not usually cartilage) from the knees of 6 of 11 rheumatoid patients, extracellular cathepsin D was commonly detected by culturing tissues with an antiserum to this enzyme.

Animals↗
PubMedDate not supplied

Serum content of the C-propeptide of the cartilage molecule type II collagen in children.

OBJECTIVE: The C-propeptide of cartilage type II procollagen, together with the N-propeptide, are removed from newly synthesized procollagen during collagen fibril assembly in cartilage matrix. The presence and content of the C-propeptide reflect the synthesis of this molecule. Recently, we showed that serum levels of the C-propeptide are increased in adults with rheumatoid arthritis, pointing to increased synthesis of this molecule. In this study we examined its content in the sera of children to determine whether it changes during development. METHODS: Sera were obtained from 44 premature infants (cord blood), 75 children (0-18 years), 14 young adults (18-22 years) and 47 adults (35-60 years). The concentration of serum C-propeptide of type II procollagen was determined by a solution phase competitive inhibition radioimmunoassay which uses a polyclonal antiserum specific for the bovine and human C-propeptide. RESULTS: Compared with adults, concentrations of the C-propeptide of type II procollagen were significantly elevated in children of ages 0-14 years. Concentrations were constant until 10 years of age (premature infants: 14.5 +/- 1.4 ng/ml, mean +/- SE; 0-10 years: 13.6 +/- 1 ng/ml). In children of ages 10-14 years, during which the pubertal growth spurt is ordinarily observed, the mean concentration increased (10-14 years: 21.6 +/- 0.7 ng/ml) although not significantly due to the variation between individuals. Concentrations at all ages younger than 14 were significantly greater than those in older adolescents ages 14-18 (6.3 +/- 0.7 ng/ml), young adults (8.4 +/- 2.0 ng/ml) and adults (5.7 +/- 0.4 ng/ml). Serum concentrations did not show significant differences with respect to sex, but varied from child to child at any given age. CONCLUSIONS: The measurement of this circulating C-propeptide may be of use in studying the biochemical and physiological bases of changes in cartilage turnover in children, and abnormalities thereof.

Adolescent↗