Search PubMed⌕ Search

Biomedical subjects

J G Craddock

Publications and source records attributed to J G Craddock.

7 recordsLinked to original sources
PubMed1977

Arthritis in rats after systemic injection of streptococcal cells or cell walls.

Further investigation of the biological properties of streptococcal cells and their components has produced a model of erosive synovitis in rats. A single intraperitoneal injection of an aqueous suspension of whole cell sonicate of group A streptococci into Sprague-Dawley rats induced an acute arthritis which evolved into a prolonged inflammatory process characterized by several complete or partial remissions, joint deformity, and ankylosis. The toxic moiety is a peptidoglycan-polysaccharide fragment of the cell wall which persists in tissue. Histologic features of the arthritis include an acute exudative phase followed by an erosive synovitis that leads to destruction of cartilage and subchondral bone and fibrous ankylosis of the joints. The arthropathic properties of whole cell sonicates of several species of streptococci are compared along with studies of the ability of heat-killed, whole cells of groups A, B, and C streptococci to induce arthritis in rats. Whole cells induce arthritis after a latent period of 57-120 days when group A cells are injected and 7-10 days when group B cells are tested.

Animals↗
PubMed1975

Bacterial aerosolization from an ultrasonic cleaner.

An ultrasonic device used for cleaning surgical instruments was found to produce a significant microbial aerosol. No correlation was found between the concentration of aerosol generated and the bacterial contamination in the cleaning solution. Table top contamination around the cleaner was due essentially to splash and dripping, and not from the settling of the aerosol. Recommendations are made for cleaning and disinfection protocols.

Aerosols↗
PubMed1967

Association of experimental chronic arthritis with the persistence of group A streptococcal cell walls in the articular tissue.

A single injection of isolated fragments of group A streptococcal cell walls into the joints of rabbits stimulated an initial acute reaction which was followed by a prolonged inflammatory process. The chronic process was characterized by hyperplasia of the synovial cells, diffuse infiltration of the villi by macrophages, and focal collections of lymphocytes in the stroma of the villi. These histological changes were similar to those seen in the early stages of rheumatoid arthritis. Antibodies specific for the mucopeptide and group-specific C polysaccharide antigens of group A streptococcal cell walls were labeled with either fluorescein or (125)I, and were used to demonstrate antigen in the synovial tissues. The antigens persisted within macro-phages for at least 5 weeks. Their presence correlated with the evolution of the chronic inflammatory process.

Animals↗
PubMed1966

Rheumatic-like cardiac lesions in mice.

A single intraperitoneal injection of a sterile extract of sonically disrupted group A streptococcal cells induced an inflammatory process in the hearts of mice. The cardiac lesions, in terms of their distribution and histological features, are similar to the cardiac lesions of rheumatic fever.

Animals↗