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C Pearce

Publications and source records attributed to C Pearce.

13 recordsLinked to original sources
PubMed1987

Isolation and characterization of mutants of Streptococcus mutans using selective removal of wild-type cells by agglutination with an agglutinin from Persea americana.

Persea americana agglutinin (PAA), a substance known to bind basic proteins and inhibit the sucrose-independent adherence of Streptococcus mutants to saliva = coated hydroxyapatite (Staat et al., 1980) was used to selectively enrich for mutants defective in a variety of cell surface associated virulence characteristics from cultures UAB62 (PS14 Riff, serotype c), UAB66 (6715 Strr Spcr, serotype g) and UAB77 (GS5, serotype c). Following mutagenesis and growth for segregation and phenotypic expression, washed cells of each strain were exposed to PAA overnight at 37 degrees C. Aggregated cells were removed by low-speed centrifugation and cells remaining in the supernatant fluids were concentrated, grown to stationary phase and the enrichment with PAA repeated. Mutants isolated following enrichment were phenotypically diverse and included strains defective in one or more of the following characteristics: adherence to glass in a sucrose-containing medium, aggregation with sucrose, dextran or PAA. dextranase production, colony morphology, cell or chain morphology, fermentation of sorbitol, lactose, galactose, raffinose, melibiose, or fructose, and production of surface protein antigen A (SpaA). The diversity of mutant phenotypes identified along with the observation that PAA could still cause aggregation (with a lower efficiency) of all mutants leads us to infer that the interaction of this agglutinin with proteins on the S. mutans cell surface is relatively nonspecific and that the observed inhibition of S. mutants attachment to saliva-coated hydroxyapatite caused by PAA is not due to a highly specific unique interaction of PAA with the protein(s) responsible for sucrose-independent adherence.

Agglutination↗
PubMed1979

Bedside angiography of the lung by Swan-Ganz catheter. A case report.

A Swan-Ganz catheter, employed for haemodynamic monitoring, was put to a use not described previously. Pulmonary angiography was performed through the catheter at the bedside with minimal discomfort or complication. In this case it was possible to determine that a lung abscess was responsible for a translucency in the right lower lobe. This was subsequently confirmed at postmortem examination.

Adult↗
PubMed1979

Cross clamping the lower abdominal aorta during vascular surgery.

The effect of cross clamping the lower abdominal aorta on systemic blood pressure and right and left heart pressure was studied in 17 patients requiring surgical treatment for abdominal aortic aneurysm or aortic occlusive disease, in neuroleptanaesthesia. After cross clamping the systemic systolic blood pressure rose 24 mmHg (p is less than 0.01) and the systemic diastolic blood pressure 8 mmHg (p is less than 0.01). There was no influence of cross clamping on the right (CVP) and and left (PCWP) heart filling pressure even in patients with preexistent readings beyond the normal range.

Aged↗