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Biomedical subjects

B Vernon-Roberts

Publications and source records attributed to B Vernon-Roberts.

At least 91 records · Page 5Linked to original sources
PubMed1984

Induction and characterisation of local (simple) calcergy in granulation tissue in the rat by lead acetate injection into polyurethane sponges.

Granulation tissue was allowed to grow into polyurethane sponges implanted subcutaneously in rats for 14 days prior to injection of saline (control) or lead acetate (PbAc) into the sponge centres. The reaction was studied for 21 days post-injection utilising sponge dry weight gain, histology and electron microscopy. Five hours after PbAc injection, calcification was demonstrable within the central tissue-free portion of the sponges. Calcification in granulation tissue was associated with collagen fibres and elicited a macrophage and multinucleated giant cell reaction. Mast cells were not found within sponges. Hydroxyapatite deposition was associated with an increase in sponge weight compared with controls. The injection of PbAc elicited calcification in granulation tissue in the same time scale reported for calcergy in mature connective tissue and the phenomenon of calcergy does not require the presence of collagen fibres or mast cells in its early stages.

Animals↗
PubMed1984

Fibre glass induced synovitis.

Chronic synovitis developed in the dorsal extensor sheath of the hand of a 25-year-old manufacturer of fibre glass reinforced boats and surfboards . Particles found in synovial fluid aspirates were similar in morphology and elemental content to unused fibre glass and particles found in dust from the workshop floor. It was concluded that hard disc grinding required during manufacture resulted in percutaneous implantation of small glass particles, leading to chronic synovitis and effusion.

Adult↗
PubMed1983

Effects of cobalt-chrome alloy wear particles on the morphology, viability and phagocytic activity of murine macrophages in vitro.

Metallic wear particles were prepared from orthopaedic cobalt-chrome alloy by milling in medium supplemented with 20% foetal calf serum to maintain particle dispersion. The size distribution of particles was determined by sedimentation and centrifugation and particle concentration was assessed using light extinction. Monolayers of mouse peritoneal macrophages were exposed to metal particles at different concentrations for varying periods. After 4 h of exposure to particle concentrations exceeding 30 micrograms/ml there was a progressive decline in cell viability, and light and electron microscopy showed that surviving cells had assumed remarkably smooth profiles and contained abundant endocytosed metal. Phagocytic uptake of polystyrene spherules was inhibited markedly by exposure to metal particles even at concentrations at which macrophages remained 100% viable, and preceded the reduction of viability at higher concentrations. The findings are consistent with a pathological role for the metallic wear particles observed frequently within macrophages in the synovial tissues around loose artificial joints in humans.

Animals↗
PubMed1983

The role of catheter surface morphology and extractable cytotoxic material in tissue reactions to urethral catheters.

Batches of urethral catheters associated with stricture formation during clinical usage were found to be amongst those causing marked acute and chronic inflammation after subcutaneous implantation in rats. The degree of inflammation did not correlate with the surface roughness of catheters assessed by scanning electron microscopy, but showed an excellent correlation with the cytotoxic effects of soluble extracts from catheters on macrophage monolayers in tissue culture. The findings suggest that stricture formation may be chemically induced and may not relate to surface roughness of catheters.

Animals↗
PubMed1983

Assessment of nonsteroidal anti-inflammatory drug combinations by the polyurethane sponge implantation model in the rat.

The anti-inflammatory effect of single doses and combinations of aspirin and commonly used nonsteroidal anti-inflammatory drugs was investigated by the polyurethane sponge implantation model of acute inflammation. Dose response curves were performed to delineate a suppressive (high) and nonsuppressive (low) dose of each drug prior to studying these doses in combination with aspirin. The results suggest that a combination of aspirin in either high or low dose does not increase the anti-inflammatory effect of other nonsteroidal anti-inflammatory drugs in this model of inflammation.

Animals↗
PubMed1982

Absence of metabolic bone disease in the proximal femur in patients with fracture of the femoral neck.

A clinical, radiological and histopathological study of femoral heads from 125 patients with fracture of the neck of the femur and from 30 cadavers was carried out to identify various risk factors. The findings showed that the Singh index was unreliable as a radiological indicator of the bone content of the femoral heads; that the bone content of the femoral head in patients sustaining a fracture of the femoral neck did not differ from that of the controls; that osteomalacia was not found in any of the heads examined; and that the distribution of trabecular microfractures did not support the hypothesis that fracture of the neck was the result of progressive fatigue. It was concluded that the single most important factor leading to fracture in this Australian population was injury caused by falls and that such injury was frequently associated with other disease processes.

Aged↗
PubMed1982

Morton's metatarsalgia due to intermetatarsophalangeal bursitis as an early manifestation of rheumatoid arthritis.

Of 50 patients in whom Morton's metatarsalgia was diagnosed during an 18-year period, 12 (24%) had rheumatoid arthritis at the time of presentation. After conservative management had failed, 20 patients had subtotal excision of the intermetatarsophalangeal bursa and associated digital nerve; in two patients, only the nerve was excised. During the follow-up period ranging from two months to 15 years, an additional eight patients developed sero-positive rheumatoid arthritis. Thus, a total of 20 patients (40%) presenting with Morton's metatarsalgia had rheumatoid disease at initial presentation or later developed this disease. Histological changes in the intermetatarsophalangeal bursa consistent with rheumatoid arthritis were found in ten patients. Of these, two were known already to have rheumatoid arthritis, three subsequently developed rheumatoid arthritis, and five do not yet have other evidence of the disease. The evidence suggests that Morton's metatarsalgia is associated with rheumatoid arthritis and is the basic etiology in a significant number of patients.

Adult↗
PubMed1979

Morphological and functional interrelationships of bone cells and matrix.

1. Bone is unique in its combination of cells, matrix and mineral. 2. It has a dual function in skeletal and mineral homeostasis. 3. Cells which are functionally different act as coordinated units depending on a variety of signals which may be hormonal, ionic, mechanical and, possibly, electrical. 4. The coordinated activity of the cells is brought about by their having an intimate structural interrelationship, by the probability of their being subject to the influence of factors contained within an extra-cellular fluid circulating around all the cells underlying the mesenchymal cell envelope, and by the possibility that the osteoclasts and osteoblasts do not represent an end-stage in differentiation. 5. The understanding of the factors which normally control cellular differentiation and function may lead to methods of reversing bone loss, rectifying the effects of metabolic bone disease and promoting the healing of fractures.

Adult↗
PubMed1979

Action of gold salts on the inflammatory response and inflammatory cell function.

Information relating to the effect and mechanism of action of gold salts on acute and chronic inflammatory processes has been reviewed. Gold salts are effective in suppressing various aspects of the acute inflammatory process although large gaps exist in the knowledge of the mechanisms involved. Available evidence indicates that gold salts affect many biochemical pathways and that interaction with enzymes plays a major role in their pharmacology. Because they are more difficult to investigate, the action of gold salts on various important aspects of chronic inflammation have not yet received much attention.

Animals↗
PubMed1978

Synovial pathology in Behcet's syndrome.

Eight specimens of synovial membrane from 6 patients with 'definite' Behcet's syndrome were available for histological examination. Only the superficial zones of the synovia were affected, all except one being replaced by dense inflamed granulation tissue composed of lymphocytes mingled with macrophages, vascular elements, fibroblasts, and neutrophils. There was a marked plasma cell infiltrate and lymphoid follicle formation in one synovium only, and there was no evidence of infection. Pannus and erosive change were present in the three specimens which included the articular surface, the erosive change being visualised radiologically in two of these. It is suggested that these appearances are characteristic of Behcet's syndrome and should be added to the list of diagnostic criteria.

Adult↗