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Biomedical subjects

A Lopez Borrasca

Publications and source records attributed to A Lopez Borrasca.

At least 19 recordsLinked to original sources
PubMed1994

The phenotype of L-CFU and its correlation with the immunological characteristics of the blast cell population in AML.

The membrane phenotype of AML clonogenic cells (L-CFU) was analyzed in 19 AML patients using an in vitro culture technique after a complement-mediated lysis assay employing a panel of six monoclonal antibodies (McAb) -HLA-DR, FMC56 (CD9), FMC27 (CD9), CD14, CD15, CD41a-. Our results show that L-CFU has a heterogeneous but immature phenotype lacking on the expression of differentiation antigens (CD14, CD15, CD41a). In addition, we observed that the L-CFU phenotype is different from that of the whole blast cell population. Interestingly, L-CFU showed a higher expression of HLA-DR antigens with respect to their progeny. Upon analyzing whether the L-CFU phenotype was related to both the morphological and immunological features of AML blast cells, it was observed that, while there is no correlation with the FAB classification, there was a partial relationship between the immunological phenotype of AML blast cells and that of L-CFU. Accordingly, the more immature AML cases showed a more differentiated L-CFU phenotype (HLA-DR+, CD9+, FMC27+) when compared with cases with a more mature blast cell phenotype. These results suggest that those AML cases with a relatively immature myeloblastic phenotype may arise from a progenitor cell that has undergone partial differentiation and that is unable to acquire myeloid differentiation antigens, while those AML cases with mature blast cells might emerge from a very early L-CFU that has the capacity to undergo a greater degree of differentiation.

Antigens, CD↗
PubMed1991

Incidence and clinical characteristics of hereditary disorders associated with venous thrombosis.

At present, different congenital defects in several proteins--antithrombin III (AT III), protein C (PC), protein S (PS), and plasminogen (PLG)--are known to be causes of hereditary predisposition to thrombosis (thrombophilia). The incidence of these hereditary disorders in our 204 patients (106 males and 98 females) with venous thromboembolism were 4% (three cases deficient in PC, three in PS, two in PLG, and one patient in AT III). Their families were studied. In all cases the disorders were inherited as an autosomal dominant trait. The first thrombotic episodes occurred at a age of below 40 years. There was no relationship between protein levels and the occurrence of thrombosis, although a significant relationship was observed between a positive history of thromboembolic disease and a diagnosis of protein deficiencies. We evaluated the differences between primary thrombosis and secondary thrombosis. The most common thrombotic sites were the deep veins. There were no differences between males and females. Evaluation of PC, PS, AT III, and PLG in patients with thromboembolic disease should be considered.

Adolescent↗
PubMed1990

Surface phenotype and immunoglobulin levels in B-cell chronic lymphocytic leukaemia.

The aim of the present study is to analyze the relationship between serum immunoglobulin (Ig) levels and the immunological phenotype and the clinicohaematological features of B-cell chronic lymphocytic leukaemia (B-CLL) in a series of 126 patients. Eighty-eight of the cases (70%) had a decreased concentration of at least one Ig. IgM and IgA were the most frequently decreased (60% and 49% respectively). A serum monoclonal gammapathy was found in 4 patients, Ig M/k in two cases and IgM/l and IgG/k in one case. Patients with hypogammaglobulinaemia had a similar surface phenotype as patients with normal Ig levels (MRFC+, sIg+, CD20+, HLA/DR+, FMC7-, CD5+, CD9+). On the other hand the cases with hypogammaglobulinaemia displayed the features of a more advanced disease, a higher incidence of organomegalies (p less than 0.05), anaemia and/or thrombopenia (p less than 0.05), a diffuse bone marrow pattern (p less than 0.05), advanced clinical stages (p less than 0.05) as well as higher levels of both peripherial blood (p less than 0.02) and bone marrow lymphocytosis (p less than 0.02). These findings suggest that the presence of hypogammaglobulinaemia in B-cell patients is probably more related to a higher tumor burden than to either certain stages of B-cell differentiation or a particular cellular phenotype.

Agammaglobulinemia↗
PubMed1989

B-cell chronic lymphocytic leukaemia: prognostic value of the immunophenotype and the clinico-haematological features.

Sixty-two previously untreated patients with B-cell chronic lymphocytic leukaemia were analysed to study the prognostic value of both the immunologic phenotype and the clinicobiologic characteristics. Univariate studies showed that none of the immunological markers analysed, sheep-rosette, mouse-rosette, slg, and HLA/DR, CD20, FMC7, CD5, and CD9 antigens, had a significant influence on survival. On the other hand, several clinical and haematological characteristics were identified as being associated with survival: 1) clinical features--presence of lymphadenopathies (P less than .05) and hepatomegaly and/or splenomegaly (P less than .04); 2) haematologic parameters--presence of anaemia and/or thrombopenia (P less than .05), the absolute peripheral blood lymphocyte count (P less than .03), and the presence of hypogammaglobulinemia (P less than .08); 3) biochemical parameters--serum uric acid (P less than .03); and 4) bone marrow histopathological features--biopsy pattern (P less than .04) and the percentage of lymphocytes in bone marrow aspirate (P less than .03). Both the Rai staging and the International Workshop on CLL staging systems were effective in identifying groups of patients with significantly different prognoses (P less than .05). Multivariate regression analysis demonstrated that the combination of three clinicopathologic characteristics (bone marrow histopathologic pattern, absolute peripheral blood lymphocyte count, and the presence or not of hypogammaglobulinaemia) had the strongest predictive relationship with survival time. In summary, our findings show that the clinicobiological and anatomopathologic parameters have much more prognostic relevance than the immunological markers analysed in the present study.

Antigens, Differentiation↗
PubMed1988

Bone marrow histopathologic patterns and immunologic phenotype in B-cell chronic lymphocytic leukaemia.

The present work analyzes the clinicobiological and immunological characteristics - the latter hitherto unexplored - of the different bone marrow histopathological patterns of the B-cell chronic lymphocytic leukaemia (B-CLL). In addition, we studied whether any or some of these parameters were able to predict the probability of a particular pattern of bone marrow involvement appearing. Of the 100 B-CLL cases studied 41 had a diffuse pattern and 59 were non-diffuse - interstitial 27, nodular 11 and mixed 21 -. Neither clinical nor immunological differences were observed among the distinct non-diffuse patterns. The patients in the diffuse group displayed an increased incidence of mu+ isotype and a higher proportion of HLA-DR and HAN-PC 1 positive cells while, conversely, reactivity with the FMC 8 McAb was lower. In addition, patients with a diffuse pattern of BM involvement displayed features of a more extensive disease: a higher incidence of adenopathies (p less than 0.05), hepatomegaly (p less than 0.01), splenomegaly (p less than 0.01), anaemia (p less than 0.01) and thrombopenia (p less than 0.01) as well as higher levels of peripheral blood lymphocytosis (p less than 0.05) and a higher percentage of BM lymphocytic infiltration (p less than 0.001). Multiple regression analysis showed that thrombopenia and splenomegaly were the two most important features in predicting the probability of a diffuse pattern.

Aged↗
PubMed1988

Clinical and immunological findings in large B-cell chronic lymphocytic leukemia.

In order to define the characteristics of B-CLL cases in which the predominant cell population is composed of large lymphocytes, we studied 97 patients with B-CLL, comparing the cell morphological features with the clinical and biological findings and the immunological phenotype of the proliferating cells. Multivariant analysis showed that there were three significantly different morphological groups: Typical CLL, large lymphocyte CLL (LLL), and CLL with prolymphocytes (CLL/PL). The LLL group showed a greater incidence of lymphadenopathies (P less than 0.05) and higher percentages of both mu + delta + cells (P less than 0.01) and Fmc/7+ cells (P less than 0.001) than in typical CLL. The main differences between LLL and CLL/PL were the peripheral blood lymphocyte count and the percentage of Fmc/7+ cells (P less than 0.002)--both higher in the CLL/PL group--and the percentage of mouse rosette-forming cells (P less than 0.01)--lower in CLL/PL. Further studies including functional assays and survival analyses could contribute to elucidating whether these groups are different entities or a single disease with marked heterogeneity.

Antibodies, Monoclonal↗
PubMed1988

Leukemias with megakaryoblastic involvement: clinical, hematologic, and immunologic characteristics.

The clinical, hematologic, and phenotypic features of 28 patients with acute leukemia with megakaryocytic involvement (AMKL) were analyzed. The prevalence of this type of leukemia in the entire series was 11.6%, with a higher incidence among patients with acute transformation of a previous myeloproliferative disorder (MPD) (24%) than among the transformed myelodysplastic syndrome (13%) patients. The incidence in the "de novo" ANLL was 8% and 16% among secondary leukemias. The presence of bone marrow fibrosis together with low WBC and normal or increased platelet counts despite a severe anemia are the most relevant features in these patients who otherwise displayed an apparently poor prognosis. Megakaryoblasts were morphologically recognized more frequently in the acute transformations of MPD than in de novo ANLL. Only two cases were considered pure AMKL, and in the remaining 26 patients, megakaryoblasts coexisted with other granulomonocytic and/or erythroid populations. Antiglycoprotein IIIa (anti-GPIIIa) (C17) and anti-GPIIb/IIIa (CDw41-, J15-) antibodies are probably the best markers for AMKL, although the monoclonal antibody against GPIX (FMC25) was also positive in a majority of cases but in a lower percentage of cells. On the other hand, megakaryoblasts were generally negative for granulocytic or monocytic markers (CD13, CD14, CD15); the expression of HLA-DR antigens in these cells was variable. Our present results indicate that megakaryoblastic involvement is more common than previously recognized. This is true not only in acute transformed leukemias but also in de novo ANLL. Although the diagnosis of these cases should be based on megakaryocytic markers, it is often possible to suspect a diagnosis according to certain clinical and hematologic features.

Adult↗
PubMed1988

Changes of contact phase proteins during haemodialysis.

Functional and immunological activities of factors XII and XI, Prekallikrein, high molecular weight kininogen and C-1-esterase inhibitor were studied in eight patients before, during and after haemodialysis. During and after dialysis sessions a significant decrease in the functional activities of Prekallikrein and high molecular weight kininogen (p less than 0.05) could be detected, whereas their immunological levels did not change. Furthermore C-1-esterase inhibitor increased after dialysis (p less than 0.05). These results indicate activation of the kinin system during haemodialysis.

Adult↗
PubMed1986

von Willebrand disease type IIC with different abnormalities of von Willebrand factor in the same sibship.

A family with von Willebrand disease has been identified in which different members of the same sibship exhibit different abnormalities of von Willebrand factor (vWF). The two most severely affected sibs (bleeding time over 20 min) had abnormalities of vWF similar to those seen in type IIC. The smallest detectable multimer was increased and the triplet structure of individual multimers was replaced with a single band. The largest multimers could not be detected and there were relatively more small multimers than intermediate sized forms. vWF antigen (vWF:Ag) was decreased to 12.5-17% by electroimmunoassay (EIA) and to 3.2-5.5% by immunoradiometric assay (IRMA). In the less severely affected sibling (bleeding time 12.5 min) there was a similar relative increase in the smallest detectable multimer. However, the larger multimers were present and the relative concentration of large to small multimers was similar to normal. The triplet structure was altered in that the relative proportion of satellite bands to the central predominant band was decreased. vWF:Ag concentrations were moderately decreased (40-80% by EIA and 25-35% by IRMA). The father and grandfather showed a vWF multimeric pattern similar to the less severely affected sibling but there was no decrease in vWF:Ag concentration and their bleeding times were normal. These observations suggest that the interplay of several genetic factors is responsible for the expression of von Willebrand disease in this family.

Humans↗
PubMed1986

Separation of human lymphocyte subclasses by rosettes with latex-lectin particles.

The specificity and affinity of eight lectins (concanavalin A, L. culinaris, P. sativum, phytohemagglutinin P, D. biflorus, soybean agglutinin, T. purpureus, and T. vulgaris) to B, T, T gamma, and T mu lymphocytes from the blood of normal subjects were determined. Lectins attached to latex particles were used to evaluate the binding of each lectin to individual cells. The rosette percentage found in each lymphocyte population expresses the specificity index and the specific sugar concentrations needed to decrease the rosette percentage by 50% is taken as the affinity index. B Lymphocytes showed a major subclass, with respect to T lymphocytes, with receptors for WGA, SBA, D. biflorus, L. culinaris, and P. sativum lectins. In contrast, T lymphocytes exhibit a greater number of cells with specific receptors for Con A, T. purpureus, and PHA lectins than B lymphocytes, the T gamma subpopulation being responsible for the specificity of the first two lectins and the T mu subpopulation for the PHA lectin.

B-Lymphocytes↗
PubMed1986

Surface marker analysis in acute myeloid leukaemia and correlation with FAB classification.

The immunological phenotype of blast cells in 102 patients with acute myeloid leukaemia (AML) was analysed with a panel of 20 monoclonal antibodies and the enzyme terminal transferase, and correlated with the FAB classification. Although a partial correlation between these two approaches could be observed, almost every morphological group contained patients from more than one immunological phenotype. The M1 and M5a leukaemias showed the most undifferentiated phenotype, often lacking in specific myelomonocytic antigens. The M3 formed a uniform group defined as My7+, Ia-, FMC8+, a phenotype which was also observed in two cases of the microgranular variant. The granulocytic (CDw15) and monocytic (CDw14) antibodies crossreacted with some M5b and M2 leukaemias, respectively. Compared with M5a, the M5b leukaemias showed a large increase in the expression of CDw14 antigen, confirming the validity of the morphological differentiation. Glycophorin-A was present in four out of five M6 leukaemias. TdT activity was demonstrated in 10% of AML cases, with a higher incidence among the monocytic variants: M4 and M5-. Eleven AML were considered as unclassifiable according to the FAB criteria and in seven of them a megakaryoblastic cell population (GP IIb/IIIa+, GPIb+) was demonstrated; this confirms the need to include the subgroup of megakaryoblastic leukaemias within the AML. Finally, a possible immunological classification for AML is proposed.

Adult↗
PubMed1986

Immunological phenotype of neoplasms involving the B cell in the last step of differentiation.

The immunological phenotype of diseases involving the last step of B cell differentiation--multiple myeloma (MM, 38 patients) and Waldenström's macroglobulinaemia (WM, 12 patients)--was analysed with a panel of monoclonal antibodies (McAb) as well as conventional markers. Most of the bone marrow plasma cells (80%) from MM patients reacted with the McAb OKT10, FMC8 and FMC48. Plasma cells were consistently negative with FMC7, Leu-1 and mouse rosettes. Ia, B1 and SIg were expressed in a minority of plasma cells (less than 30%) in half of the cases. The circulating neoplastic cells from five MM patients showed a more immature phenotype, with a higher reactivity for OKIa, B1 and increased SIg and a lower expression of CIg, than bone marrow plasma cells. The malignant cells of WM patients differed from those of MM in the reactivity with FMC7, being positive in 10 out of 11 cases, and in their high expression of B1, Ia and SIg with a predominant mu+ phenotype. Mouse rosettes and Leu-1 were positive in one case; OKT10 was positive in three out of five WM patients studied. This phenotype indicates that WM cells correspond to an earlier stage of B cell differentiation than MM plasma cells. The McAb J5 was positive in three out of six MM and two out of four WM analysed. The antigenic differences observed in MM and WM patients support the notion that the cells of the neoplastic clone are able to undergo a certain degree of differentiation.

Antibodies, Monoclonal↗
PubMed1984

Congenital deficiency of vitamin K-dependent coagulation factors and protein C.

A 15-month-old girl from Coimbra (Portugal) had a history of numerous hemorrhagic episodes with multiple bruises, hematomas but not hemarthroses. On serial testing she showed deficiency of factors II, VII, IX, X and protein C. Malabsorption-induced vitamin K deficiency, liver disease or ingestion of a coumarin compound were excluded. An absence of detectable abnormalities was found among her relatives. Consanguinity was not present. The immunologic assay, immunoelectrophoresis or antibody neutralization, revealed much higher levels of these factors than the clotting assay. The non-physiological activator (Echis carinatus venom) produced higher levels of prothrombin activation than those detected by physiological activation. Two-dimensional immunoelectrophoresis of the patient's plasma in calcium showed that prothrombin had the same mobility as acarboxyprothrombin. No significant response to large doses of intravenous vitamin K3 (6 mg) was observed. Transfusion of 120 ml of frozen fresh plasma led to an immediate increase in the procoagulant activities of vitamin K dependent protein, similar to that found after perfusion of plasma plus vitamin K3. The results obtained from this patient suggest a defect in the gammacarboxylation mechanism inside the hepatocyte.

Blood Coagulation Disorders↗