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N Pujol-Moix

Publications and source records attributed to N Pujol-Moix.

At least 37 records · Page 2Linked to original sources

Abnormal levels of platelet-specific proteins and mitogenic activity in myeloproliferative disease.

It has been postulated that platelet-derived growth factor and platelet factor 4 (PF4) are involved in the imbalance of the mechanism of medullar stroma maintenance which triggers off the bone marrow myelofibrotic process. In this work we compare the PF4 and the beta-thromboglobulin (beta-TG) and mitogenic activity in platelet-poor plasma (PPP) and platelet extracts (PE) from patients with myeloproliferative disorders (MPD) with those of secondary thrombocytosis (ST) and normal volunteers. Statistically significant differences were found between MPD and ST patients or controls, but none between ST and controls in all the parameters studied. Maximal differences in platelet-derived factors (PDFs) between MPD and control groups were found in polycythemia vera patients. However, the relationship between the presence of myelofibrosis and abnormal levels of beta-TG, PF4 and mitogenic activity in PPP and PE was only observed in patients with agnogenic myeloid metaplasia (AMM). These results show that PDFs are specifically decreased in MPD platelets. Furthermore, no statistical correlation was found between PDFs and the number of platelets. However, other unknown factors or conditions would be necessary to develop myelofibrosis in MPD, which is present in AMM.

Adult↗

Detection of both type 1 and type 2 plasminogen activator inhibitors in human monocytes.

Increasing evidence suggests the involvement of leukocytes in the fibrinolytic system. Monocytes secrete pro-urokinase (Grau, Thromb Res 1989; 53: 145) and it has been shown that these cells have specific receptors for urokinase and plasminogen (Miles, Thromb Haemostas 1987; 58: 936). The aim of this study was to analyse the presence of plasminogen activator inhibitor(s) in platelet-free suspensions of human peripheral blood monocytes and polymorphonuclear leukocytes (PMN). SDS-PAGE and reverse fibrin autography showed an inhibitory band of 50 kDa in the monocyte extracts (Triton X-100) but not in the PMN extracts. Urokinase (u-PA) was mixed with increasing amounts of monocyte extract for 10 min and the mixtures were added to 125I-fibrin coated wells containing plasminogen. A dose-dependent decrease in the u-PA fibrinolytic activity was observed. The amount of inhibition increased when the monocyte releasates were preincubated with u-PA (40% inhibition after 5 min preincubation and 80% after 15 min), indicating a direct interaction between this activator and an inhibitor(s). After SDS-PAGE of monocyte extracts, immunoblotting and peroxidase staining identified both PAI1 and PAI2, with an apparent molecular weight of 47-50 kDa. Monocyte-associated PAI1 formed complexes with single chain t-PA with a molecular mass 50 kDa higher than the molecular mass of the free PAI1. However, a significant amount of PAI1 remained unbound to t-PA. This inactive PAI1 could have come from a rapid inactivation of the primary active PAI1. These PAI1 and PAI2 detected in human monocytes may be transcendent in the regulation of the fibrinolytic system.

Electrophoresis, Polyacrylamide Gel↗

Immunophenotype of blast cells in acute myelofibrosis.

The immunophenotype of peripheral blood blast cells from six patients with acute myelofibrosis was studied using a panel of monoclonal antibodies directed against granulocytic, erythroid, megakaryocytic and lymphoid antigenic determinants. In all patients most of the blast cells were labeled with anti-HLA-DR and with the early myelomonocytic antibodies My7 (CD13), My9 (CD33) and B1-3C5 (CD34) (3/3). In three cases, platelet antibodies Edu3 (CD41) and GPIIIa (CD61) reacted with about 30% of blast cells. TdT was positive in two out of six samples studied. Lymphoid markers T3 (CD3), Leu9 (CD7), J5 (CD10), B4 (CD19) and B1 (CD20) were negative in all cases. These results suggest that blast cells are mainly of immature myelocytic origin. However, the coexistence of megakaryoblasts cannot be ruled out in the cases with a proportion of cells that are positive with Edu3 and GPIIIa antibodies.

Acute Disease↗

Use of monoclonal anti-actin as a megakaryocyte marker in paraffin wax embedded bone marrow biopsy specimens.

Monoclonal anti-actin was used as a marker of megakaryocytes in Zenker's fixed, paraffin wax embedded bone marrow tissue, using an immunoperoxidase staining method. Twenty bone marrow samples were studied, including controls, and different myeloproliferative and myelodysplastic syndromes. The results were compared with those obtained using factor VIII related antigen (F VIII RAg) immunolabelling. Anti-actin is as good a marker for megakaryocytes as anti-FVIIIRAg and is potentially clinically useful when morphological identification is difficult, when bone marrow aspiration is unsuccessful, or when quantitative evaluation of tissue sections is required.

Actins↗

Acute erythroblastic leukemia. Cytological, cytogenetic and phenotypic studies in one case.

We report the clinical, cytological, immunophenotypic, and cytogenetic findings in one patient with acute erythroblastic leukemia. Blast cells were identified by their reactivity with the early erythroid antibodies FA6-152 and carbonic anhydrase I. The leukemic blasts had no specific differentiating features identifying them as erythroblasts even at an ultrastructural level. Cytogenetic studies revealed multiple chromosome aberrations: 45,XX,i(11q),-16,-17,-21,+der(21)t(21;?)(q22;?),+mar 1.

Aged↗

Coincident multiple myeloma and non-Hodgkin's lymphoma with 2 serum monoclonal immunoglobulins.

A case with features of both multiple myeloma and non-Hodgkin's lymphoma at the moment of diagnosis is presented. The patient had lytic bone lesions and biclonal gammopathy, IgM kappa and IgA kappa. In the bone marrow biopsy, there was a diffuse infiltration by atypical plasma cells coexisting with an interstitial and nodular infiltration by poorly differentiated lymphoid cells. Immunofluorescence studies showed positive staining with alpha and kappa antisera in the cytoplasm of plasma cells and with mu and kappa antisera on the surface of lymphoid cells. After the beginning of chemotherapy, the IgA kappa monoclonal protein disappeared and the IgM kappa monoclonal protein remained constant.

Aged↗