Monocyte chemotactic S19 ribosomal protein dimer in atherosclerotic vascular lesion.

To elucidate the molecular mechanism inducing monocyte/macrophage infiltration in the atherosclerotic lesion, we measured the monocyte chemotactic capacity in the extracts of aortic lesions. Five out of seven extracts exhibited significant chemotactic activities. Immunohistochemical examination with an anti-CD68 monoclonal antibody demonstrated that the five positive lesions possessed obvious monocyte/macrophage infiltrations at the intima, whereas the two negative lesions did so at significantly lower intensities. We subjected the chemotactic extracts to immunological analyses to identify the monocyte chemoattractant in them. The monocyte chemotactic capacities of all positive extracts were removed with anti-S19 ribosomal protein (RP S19) antibody beads and antimonocyte chemoattractant protein-1 (MCP-1) antibody beads. In three of the five extracts, the anti-RP S19 antibody beads were more effective than the anti-MCP-1 antibody beads for removal, while in the remaining two extracts, the opposite was observed. A combined immunoabsorption with these beads depleted the monocyte chemotactic capacity of a representative sample of each group. Consistently, the chemotactic capacity of an apparently RP S19 dimer-predominant extract was strongly inhibited by the presence of a C5a receptor antagonist. These results suggest that the RP S19 dimer and MCP-1 play a major role in the monocyte/macrophage infiltration of the atherosclerotic vascular lesion.

Coronary artery bypass grafting using a bifurcating radial artery.

A 61-year-old man with angina pectoris was admitted for elective coronary artery bypass grafting. The left anterior descending artery, and the two posterolateral branches (PLA1 and PLA2) of the circumflex artery required bypass grafting. At operation, the distal portion of the left radial artery was found to bifurcate, both branches having an equal size. We decided to use the bifurcating radial artery as a conduit for bypass grafting to the branches of the left circumflex artery. One distal end of the radial artery was subsequently anastomosed to the PLA1 branch and the other distal end was anastomosed to PLA2. Postoperative coronary angiography showed both branches of the radial artery to have good patency.

Predictive factors for platelet number after cardiopulmonary bypass and postoperative blood loss.

We retrospectively searched for factors that can predict the circulating platelet count after cardiopulmonary bypass (CPB) and postoperative blood loss. Correlations between the circulating platelet count after CPB and several other perioperative variables were investigated in 42 patients who underwent cardiac surgery using the same type of oxygenator. Correlations between perioperative variables and 24 hour postoperative blood loss were also investigated. A multiple stepwise regression analysis showed that the preoperative platelet count, age, and intraoperative blood transfusion values were independent predictors of the circulating platelet count after CPB (R2 = 0.661, p < 0.0001). Gender, operation type, and priority (elective or urgent) were not associated with the platelet count after CPB or postoperative blood loss. Independent predictive factors for postoperative blood loss consisted of age and intraoperative blood loss (R2 = 0.231, p = 0.006). In addition to preoperative platelet count, age and amount of intraoperative blood transfusion are predictive factors for circulating platelet count after CPB. The association of postoperative blood loss with age and intraoperative blood loss may suggest friability of the tissues, including blood vessels, in elderly patients.