G Mazzini — Page 6 | PubMed Health

PubMedDate not supplied

DNA content and cell kinetics in colorectal carcinoma: flow cytometric analysis of primary tumor and liver metastases.

AIMS AND BACKGROUND: Both flow cytometric DNA ploidy and proliferative activity have been indicated as potential prognostic indicators in colorectal cancer. Due to tumor biological heterogeneity, these parameters are best assessed with multiple sampling. METHODS: We undertook a prospective study on 52 patients with Duke's D colorectal tumors looking at multiple samples of the primary tumors and liver metastases. DNA ploidy and tumor proliferative activity (derived from proliferating cell nuclear antigen, PCNA FCM expression) were evaluated. RESULTS: Of primary tumors, 36/52 (69.2%) were aneuploid in at least 1 sample, with a median value of the DNA index of the aneuploid peak of 1.58. On liver metastases, 42/52 (80.7%) patients were aneuploid in at least 1 sample with a median DNA index of the aneuploid peak of 1.64. Identical or nearly identical histograms from different tumor samples were observed in only 18/52 (34.6%) of the primary tumors and in 15/52 (28.8%) of the liver metastases. The PCNA values for primary tumors ranged from 5 to 28% (median value = 16.5%). In the liver metastases, PCNA values ranged from 12 to 38% (median value = 19.8%). Proliferative activity was lower for diploid than for aneuploid tumors. DNA ploidy and PCNA expression of the deep specimen of primary tumors were similar to those of the liver metastasis of the same patient while this concordance was not complete in the case of superficial biopsy specimens. CONCLUSIONS: If correctly performed, FCM techniques allow an accurate analysis of DNA ploidy and proliferative activity and both these measurements can offer considerable potential for a more comprehensive approach to colorectal cancer.

Adenocarcinoma↗

PubMedDate not supplied

Platelet composition and function in patients undergoing cardiopulmonary bypass for heart surgery.

BACKGROUND: Previous studies showed severe biochemical and functional damage to platelets in patients undergoing cardiopulmonary bypass for cardiac surgery, and suggested that this derived from the proteolytic action of plasmin on the platelet surface. METHODS: A double-blind study was carried out to compare platelet function and composition in patients randomized to receive the protease inhibitor aprotinin or placebo during reoperation for valvular prosthesis replacement or coronary artery bypass grafting. RESULTS: Flow cytometry with specific monoclonal antibodies and polyacrylamide gel electrophoresis did not show any significant proteolysis of platelet glycoprotein Ib and IIb-IIIa either in the placebo or the aprotinin group. Functional studies were consistent with these results, since ristocetin-induced platelet agglutination was unchanged and platelet aggregation and ATP release induced by collagen and ADP were only slightly reduced by cardiopulmonary bypass. These mild defects in platelet function were partially prevented by aprotinin infusion. CONCLUSIONS: On the basis of our data and those from literature, we suggest that platelets may be affected very little or severely damaged during cardiopulmonary bypass for cardiac surgery, probably depending on some aspects of the technical procedure which remain to be identified. Aprotinin infusion significantly protects platelets in the latter condition, while its role is obviously slight in the former.

Aprotinin↗