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Biomedical subjects

D A Rees

Publications and source records attributed to D A Rees.

At least 91 records · Page 5Linked to original sources
PubMed1977

Rapid isolation of plasma membranes in high yield from cultured fibroblasts.

1. A method was developed which allows the rapid preparation of pure plasma membranes in high yield from cultured fibroblasts. 2. Cells are lysed in hypo-osmotic borate/EDTA and, after differential centrifugation, the membranes collected by centrifugation on a sucrose barrier. 3. Electron microscopy of the isolated material shows large membrane vesicles essentially free from contaminating organelles. 4. There is no detectable activity of the endoplasmic-reticulum enzyme marker, NADH2--lipoamide oxidoreductase (EC 1.6.4.3), and that of succinate dehydrogenase (EC 1.3.99.1), a marker for mitochondria, is substantially decreased. Chemical compositions are in good agreement with previous observations. 5. This study confirms the usefulness of applied isotopic markers for isolating plasma membranes.

Borohydrides↗
PubMed1977

Control of grip and stick in cell adhesion through lateral relationships of membrane glycoproteins.

Although cell adhesion to substrate must ultimately depend on 'sticking' by physical forces at the outer surface, we suggest that control is exercised through the 'grip' of the cytoskeleton. Our experiments indicate that grip can be relaxed by agents which release surface glycoproteins from some form of side-to-side organisation, and can be consolidated by suitable cross-linking to augment this organisation.

Animals↗
PubMed1976

Mechanisms of cell adhesion: early-forming junctions between aggregating fibroblasts.

When cultured fibroblasts (16C) are mildly dissociated with EGTA or trypsin/EDTA, they aggregate rapidly. The formation of aggregates has been found to involve junctions of the gap and adhaerens types which are seen by electron microscopy within minutes of allowing cells to come together. The process of adhesion between freshly dissociated, transformed 16C fibroblasts is therefore organized and establishes its usefulness as a model for studying cellular interactions in relation to supracellular organization.

Cell Adhesion↗
PubMed1975

Gynandroblastoma of the ovary.

A gynandroblastoma of the ovary in a 17-year-old girl is reported. Primary amenorrhoea, hirsuties and slight clitoral enlargement were associated with the tumour and high levels of circulating testosterone were found. This is the first gynandroblastoma in which Reinke crystalloids have been identified in the Leydig cell component. The criteria for the diagnosis of this tumour and its histogenesis are discussed.

17-Hydroxycorticosteroids↗
PubMed1973

Hyaluronic acid: a novel, double helical molecule.

Films prepared from a deformable gel (or putty) of hyaluronic acid show high crystallinity and orientation in their x-ray diffraction patterns. We have derived a probable structure for the molecules in these films. This is a double helix in which two identical, left-handed strands are antiparallel to one another. Each strand has four disaccharide residues per pitch length. Although the putty is prepared at pH 2.5, at which dilute solutions of hyaluronic have exaggerated rheological properties, the double helical form can also exist at physiological pH and therefore may be a biologically important form.

Circular Dichroism↗