Reduced platelet aggregation in women after intercourse: a possible role for the cyclooxygenase pathway.

We hypothesise that molecules in the cyclooxygenase pathway affect platelet activity when seminal fluid (SF) is present. We considered the influence of SF on platelet aggregation in women, and believe that the prostanoids in SF signalling are significant. Thirty-one female subjects were studied, 20 of whom were sexually active. Male partners were given either aspirin or indomethacin to inhibit cyclooxygenase. The 6-keto prostaglandin F1α (6-keto PGF1α) and prostaglandin E metabolite (PGE-M) in SF were measured by competitive assay. Platelets and prostanoids were evaluated in women, periodically, before and after intercourse. The platelets were tested with adenosine diphosphate (ADP) and arachidonic acid (AA). To block the interaction between the uterus and SF, some couples used condoms. We found that the 6-keto prostaglandin F1α in urine at 2 hours post-intercourse (1418.75 pg/mL, Std 688.39) was greater than pre-intercourse (772.68 pg/mL, Std 116.54). Post-intercourse, a transient decrease in platelet aggregation was observed in women whose partners did not use condoms. Averages for platelet aggregation were 20.16% with ADP, and more significantly, 37.79% with AA after 2 hours. In contrast, couples using condoms showed no changes, averaging 64.02% with ADP and 72.06% with AA. Women whose partners were taking aspirin or indomethacin also showed no changes. SF from men taking aspirin or indomethacin led to no reduction in platelet aggregometry in their partners. These results indicate that in cases of exposure to SF, the transient change in women's platelet activity could be related to the cyclooxygenase pathway.

Expression of antigen tf and galectin-3 in fibroadenoma.

BACKGROUND: Fibroadenomas are benign human breast tumors, characterized by proliferation of epithelial and stromal components of the terminal ductal unit. They may grow, regress or remain unchanged, as the hormonal environment of the patient changes. Expression of antigen TF in mucin or mucin-type glycoproteins and of galectin-3 seems to contribute to proliferation and transformations events; their expression has been reported in ductal breast cancer and in aggressive tumors. FINDINGS: Lectin histochemistry, immunohistochemistry, and immunofluorescence were used to examine the expression and distribution of antigen TF and galectin-3. We used lectins from Arachis hypogaea, Artocarpus integrifolia, and Amaranthus lecuocarpus to evaluate TF expression and a monoclonal antibody to evaluate galectin-3 expression. We used paraffin-embedded blocks from 10 breast tissues diagnosed with fibroadenoma and as control 10 healthy tissue samples. Histochemical and immunofluorescence analysis showed positive expression of galectin-3 in fibroadenoma tissue, mainly in stroma, weak interaction in ducts was observed; whereas, in healthy tissue samples the staining was also weak in ducts. Lectins from A. leucocarpus and A. integrifolia specificaly recognized ducts in healthy breast samples, whereas the lectin from A. hypogaea recognized ducts and stroma. In fibroadenoma tissue, the lectins from A. integrifolia, A. Hypogaea, and A. leucocarpus recognized mainly ducts. CONCLUSIONS: Our results suggest that expression of antigen TF and galectin-3 seems to participate in fibroadenoma development.

O-glycosylation expression in fibroadenoma.

Fibroadenomas are human benign breast tumors characterized by proliferation of epithelial and stroma cells of the terminal ductal unit. Expression of O-glycans seems to contribute to the proliferation and transformation events. With this in mind, we evaluated the expression of glycans in fibroadenoma tissue through immunohistochemistry with antibodies against mucin epitopes (Anti CA15-3 and MUC1), as well as with lectins specific for glycans linked to proteins or lipids, and we compared findings with healthy breast specimens. Our results show positive expression of CA15-3 and MUC1 in fibroadenoma tissue, mainly in duct and stroma cells, whereas, in normal samples, staining was observed in duct cells. The lectin from Glycine max recognized equally well duct and stroma cells; this was the only lectin showing co-localization with anti-CA15-3 in healthy and tumor tissues. Dolichos biflorus, Artocarpus integrifolia, and Griffonia simplicifolia lectins recognized duct cells in control healthy tissues as well as in fibroadenoma tissue. The lectin from Amaranthus leucocarpus recognized only duct cells in control samples, whereas, in fibroadenoma tissue, it recognized duct and some stromal cells, suggesting that O-glycans-type mucin linked to proteins and mucin participate in the development of fibroadenomas.

Molecular association of lectin and beta-glucosidase in corn coleoptile.

Corn coleoptile lectin is present with beta-glucosidase (EC. 3.2.1.2.1) in a single tightly bound molecular association complex (88.7 kDa). SDS-PAGE of the molecular complex dissociates into two main components. Of these, at a concentration of 75%, the corn coleoptile beta-glucosidase (60 kDa) is identified by enzymatic activity, with two 16-amino acid tryptic peptides displaying close homology with the primary structure of the enzyme. In separate experiments, we isolated homogenous monomeric enzyme of corn coleoptile. This allowed us to conclude that lectin properties like erythrocyte agglutination, found in the (88.7 kDa) molecular complex, is not due to the beta-glucosidase bound in it. Another protein (30 kDa) dissociated from the same SDS-PAGE gels rendered several tryptic peptides, including a 20-amino acid sequence V(L)GP(Q)W(A)GGSGGSPVDITAEPQR closely homologous to the putative beta-glucosidase aggregating factor (BGAF) precursor described recently. Tryptic peptide SAFTE(A)WN(V)ELK(V) was also present in the BGAF precursor. KFHEQR peptide was not present in BGAF precursor or any other protein sequence examined. Tryptic peptide TYGPFGA showed good homology with the BGAF precursor protein, FEGLYLFHTPLGSGAN peptide displayed identity with the BGAF precursor sequence. Thus, the 30 kDa protein does not appear to be identical to BGAF, but is rather a similar molecule which could be endowed with the lectin properties of the 88.7 kDa molecular complex.