José L. Navarro

Diabetes mellitus as a hypercoagulable state: Its relationship with fibrin fragments and vascular damage

Haemostatic variables were assessed in 43 patients, 28 insulin-dependent and 15 non insulin-dependent. Maximum aggregation by low concentrations of adenosine diphosphate (ADP) or arachidonic acid and elevated plasma concentrations of TxB2, Factor VIII, vWF:Ag, RCoF and fibronectin (Fnct) indicated a hypercoagulable state. The manifestation of vasculopathy was associated with elevated concentrations of RCoF, Fnct, Hbalc, cholesterol and triglycerides, while impaired fibrinolysis was demonstrated by decreased t-PA levels and the absence of crosslinked fibrin degradation products (XL-FDP).

Immunophenotypic characterization of human bone marrow mast cells. A flow cytometric study of normal and pathological bone marrow samples

The goal of the present paper was to define the immunophenotype of bone marrow mast cells (BMMC) from healthy controls and patients with hematologic malignancies (HM) based on the use of multiple stainings with monoclonal antibodies analyzed by flow cytometry. Our results show that BMMC from both groups of individuals display a similar but heterogenous immunophenotype. The overall numbers of BMMC are higher in the HM group of individuals (p = 0.08). Three patterns of antigen expression were detected: (1) markers constantly positive in all cases analyzed (CD9, CD29, CD33, CD43, CD44, CD49d, CD49e, CD51, CD71, CD117, and FcεRI), (2) antigens that were constantly negative (CD1a, CD2, CD3, CD5, CD6, CD11a, CD14, CD15, CD16, CD19, CD20, CD21, CD23, CD25, CD30, CD34, CD38, CD41a, CD42b, CD65, CD66b, HLA-DR, and CD138), and (3) markers that were positive in a variable proportion of cases – CD11b (50%), CD11c (77%), CD13 (40%), CD18 (20%), CD22 (68%), CD35 (27%), CD40 (67%), CD54 (88%) and CD61 (40%). In addition, BMMC from all cases explored were CD45+, and this antigen was expressed at an intensity similar to that of mature granulocytes. In summary, our results show that BMMC from both healthy controls and HM patients display a relatively heterogenous immunophenotype. Interestingly, we have observed clear differences between the immunophenotype of BMMC and MC from other tissues. This could be due either to the heterogeneity of human MC according to their tissue localization or to the sensitivity of the method used for antigen detection.

Expression of Bcl-2 by human bone marrow Mast Cells and its overexpression in Mast cell leukemia

Bcl‐2 protein plays a major role in the prevention of programmed cell death of differentiating cells. In the present study, the expression of cytoplasmic bcl‐2 by human Bone Marrow Mast Cells (BMMC) from both normal and pathological bone marrow samples was examined. A total of 35 subjects corresponding to 9 healthy volunteers, 8 cases of adult indolent systemic mast cell disease (SMCD), 4 cases of pediatric mastocytosis (PM), 11 cases of hematological malignancies (HM), 2 cases of reactive bone marrow, and 1 case of mast cell leukemia (MCL) were analyzed. The expression of bcl‐2 was studied using quantitative three‐color flow cytometry. We also studied the molecular configuration of the bcl‐2 gene and other relatives by Southern blot and polymerase chain reaction (PCR) in the MCL case. Bcl‐2 expression was detected in BMMC from all samples analyzed. No significant differences on the expression of bcl‐2 were detected between BMMC from healthy subjects and patients with SMCD, PM, HM, and reactive bone marrow. By contrast, bcl‐2 protein was overexpressed in BMMC from MCL patient without gene rearrangement. Our results show that bcl‐2 protein was constitutively expressed by BMMC. BMMC from MCL display overexpression of bcl‐2, which could not be related to molecular rearrangements involving the bcl‐2 gene. The expression of this protein by mature MC may play a role in the prevention of MC apoptosis and thus help to explain the long survival of these cells. The overexpression of bcl‐2 by BMMC in MCL may help to explain their resistance to chemotherapy‐induced apoptosis. Am. J. Hematol. 60:191–195, 1999.

Expression of lymphoid-associated antigens in mast cells: report of a case of systemic mast cell disease

Summary. In this study the expression of‘classically’considered lymphoid‐associated antigens (CD2, CD3, CD4, CD5, CD7, CD8, CD10, CD19, CD20, and CD22) was explored both in peripheral blood (PB) and bone marrow (BM) mast cells (MC) in a case of systemic mast cell disease (SMCD) by means of using multiple stainings and a direct immunofluorescence technique. CD2 and CD22 were expressed in both PB and BM MC, all the remaining lymphoid‐associated markers were negative. Our results suggest that the reactivity for both CD2 and CD22 in PB and BM MC would be aberrant.

The CD69 early activation molecule is overexpressed in human bone marrow mast cells from adults with indolent systemic mast cell disease.

We have analysed the quantitative expression of surface CD69 antigen on human mast cells (MC), from both normal and pathological bone marrow (BM) samples, using flow cytometry. Our major aim was to analyse whether CD69 is constitutively expressed by normal BMMC and to explore the possible differences between CD69 expression by BMMC from normal controls and patients suffering from different pathological conditions.

The role of bone marrow biopsy and FDG-PET/CT in identifying bone marrow infiltration in the initial diagnosis of high grade non-Hodgkin B-cell lymphoma and Hodgkin lymphoma. accuracy in a multicenter series of 372 patients

Bone marrow infiltration (BMI), categorized as an extra‐nodal site, affects stage and is associated with poor prognosis in newly diagnosed lymphoma patients. We have evaluated the accuracy of PET/CT and bone marrow biopsy (BMB) to assess BMI in 372 lymphoma patients [140 Hodgkin Lymphoma (HL) and 232 High Grade B‐cell non‐Hodgkin Lymphoma (HG B‐NHL), among them 155 Diffuse Large B‐Cell Lymphoma (DLCL)]. For HL cases, and taking into account PET/CT, sensitivity, negative predictive value (NPV) and accuracy were 96.7, 99.3, and 99.3% while those of BMB were 32.3, 83.8, and 85%, respectively. For HG B‐NHL and considering PET/CT, sensitivity, NPV, and accuracy were 52.7, 81.7, and 84.1%, while those of BMB were 77.6, 90.2, and 90.7%, respectively. In the HG B‐NHL group, 25 patients would have been under‐staged without BMB. These results lead us to recommend PET/CT and the avoidance of BMB to assess BMI in HL. In the case of HG B‐NHL, bone marrow status should be assessed firstly by means of PET/CT; only in either focal or diffuse PET/CT with low borderline SUV max values or in negative cases, should BMB be carried out afterwards. In the HG B‐NHL setting and at the present moment, both techniques are complementary. Am. J. Hematol. 90:686–690, 2015.

Coagulative System Activation and Fibrinolytic System Inhibition Activities Arise From Tumoral Draining Vein in Colon Carcinoma

UNLABELLED Hypercoagulability and activation/inhibition of the fibrinolytic system have been observed in abdominal cancer surgery. Because surgery itself and also neoplastic diseases are associated with these situations, a method for separating the origin of these two processes was designed. Eighteen patients with colon cancer who underwent a surgical procedure were studied: Immediately before surgery blood was taken from a peripheral vein. During the surgical procedure, before the exclusion of tumoral tissue from general circulation and at the same time of a second peripheral vein blood sample, a blood sample was taken from the main tumoral draining vein. Platelet-poor plasma samples were aliquoted and stored at -72 degrees C, ready for analytical procedures. RESULTS A moderate activation of the fibrinolytic system during surgery was observed, expressed by elevation of tissue plasminogen activator (t-PA) (P<.05) and D-dimer (DD) (P<.05) levels, without changes in fibrinogen (FG), plasminogen (PG) or antiplasmin (AP) levels. There were no modifications in antithrombin III (AT-III) and protein C (PC) levels. In the tumoral draining vein samples, there was a high elevation of levels of thrombin-antithrombin III complexes (TAT) (P<.001) and PAI-1 (P<.01), compared with the second sample peripheral vein. There was no difference between peripheral and tumoral vein sample levels of AT-III, PC, FG, DD, PG and AP. CONCLUSIONS The tumour itself is the origin of hypercoagulability (TAT) and fibrinolytic system inhibition (PAI-1); the surgical procedure elicits an evident though moderate activation of the fibrinolytic system (t-PA and DD elevation).

Phospholipase A2 activity in platelets of patients with uremia

There is substantial evidence that platelet production and release take place in the lungs. Thrombopoietin (Tpo) stimulation can cause platelet release in the pulmonary vasculature. On the other hand, myelofibrosis can occur in Tpo-overexpressing transgenic mice models, and there is unexplained pulmonary hypertension in chronic myeloproliferative disorders including primary myelofibrosis. In this study, we aimed to assess local Tpo concentrations inside the pulmonary artery and associated vessels in humans. We measured Tpo concentrations in plasma samples taken concurrently from the right ventricle, the pulmonary artery, and the left ventricle during cardiac catheterization in patients with and without pulmonary hypertension. The study group comprised 10 patients with normal pulmonary arterial pressure (Group A, male/female 4/6, mean age 48 +/- 19) and 14 patients with pulmonary hypertension (Group B, male/female 9/5, mean age 57 +/- 16). The Tpo levels inside the right ventricle, the pulmonary artery and the left ventricle were 33.3 +/- 15.6, 47.2 +/- 33.9, and 34.4 +/- 18.6 pg/ml, respectively, in Group A; and 85.0 +/- 39.8, 128.4 +/- 50.4, and 81.5 +/- 35.5 pg/ml, respectively, in Group B. Levels of the Tpo were significantly higher in all three localizations in Group B compared to Group A. Moreover, the Tpo concentration inside the pulmonary artery is significantly higher than the Tpo concentrations in the right and left ventricles in Group B patients. There were positive correlations between the Tpo levels and pulmonary artery systolic pressure over the whole patient group. In conclusion, there could be an association between pulmonary hypertension and Tpo level. Moreover, lung vasculature holding the major regulatory thrombopoietic hormone, Tpo, may be an important place for megakaryocytopoiesis.Platelets of patients with uremia develop a defective platelet function and have a decreased production of thromboxane B2 (TxB2). Activated platelets generate thromboxane from free arachidonate that is previously released from the membrane phospholipids (PLs) by phospholipases. Phospholipase A2 (PLA2) release up to 70% of the arachidonate in normal platelets, and to date, the activity of this enzyme in uremia is unknown. This work studied the PLA2 activity in the platelets of nine uremic patients and nine healthy volunteers. Washed platelets were labelled with [ 14 C]arachidonic acid and activated with calcium ionophore A-23187 (4 w gr/ml). Lipids were resolved by TLC and identified by autoradiography. The distribution of [ 14 C]arachidonic acid in the five major platelet phospholipids was found to be normal. Uremic platelets released more radioactivity than normal platelets (19.0 - 5.2% versus 11.3 - 1.6%, P = 0.001). The production of both, radioactive thromboxane B2 and hydroxyheptadecatrienoic acid was normal (2.6 - 1.2% and 3.5 - 1.6% of total radioactivity respectively), but the formation of the lipoxygenase metabolite hydroxyeicosatetraenoic acid was increased with respect to the controls (12.9 - 4.6% vs 7.0 - 1.3% of total radioactivity, P = 0002). In conclusion, platelets of patients with uremia have an increased activity of phospholipase A2 and produce increased amounts of hydroxyeicosatetraenoic acid, an inhibitor of the platelet function.

Endogenous peroxidase activity in human cutaneous and adenoidal mast cells.

We have studied peroxidase activity in human cutaneous and adenoidal mast cells using different methods, in order to determine the optimal technical conditions for its demonstration. In 1.25% glutaraldehyde-fixed cells, no peroxidase activity was seen. On the contrary, in tannic acid-aldehyde-fixed cells or in unfixed cells peroxidase activity was revealed independently of the DAB concentration or the incubation time in DAB medium. The reaction product was localized in perinuclear cisternae and endoplasmic reticulum. Granules were always unreactive with all techniques employed. Golgi apparatus was generally negative and only occasional cells exhibited one or two positive peripheral cisternae. This activity appears sensitive to fixation by glutaraldehyde and is inhibited by 3-amino-1,2,4-triazole (AMT) and by lack of H2O2 or DAB in the incubation medium, but not by potassium cyanide, sodium azide, or sodium pyruvate, at the concentrations used. The peroxidase activity described in this report is an endogenous peroxidase and is not related to uptake of exogenous peroxidase by mast cells. It can therefore be considered as an ultracytochemical marker of human mast cells.

Familial occurrence of primary antiphospholipid syndrome

venom (dRVV) were prolonged. LA was found positive according to the criteria of the scientific subcommittee for LA [11]. ACAs were also positive (Table 1). Over the next 10 years, she had four