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Biomedical subjects

A Villegas

Publications and source records attributed to A Villegas.

At least 91 records · Page 5Linked to original sources
PubMed1994

[Molecular heterogeneity of beta thalassemia].

PURPOSE: To check out the incidence of beta-thalassaemia in different regions of Spain and to demonstrate its heterogeneity. PATIENTS AND METHODS: The study was performed on 60 peripheral blood samples from patients diagnosed of beta-thalassaemia by conventional methods, namely, microcytosis, HbA2 over 3.5%, increased HbF. DNA was isolated with phenol-chloroform and amplified by ARMS technique, and in one case its sequence was established according to Sanger's method. RESULTS: The mutations found in the 67 alleles studied showed similar incidence, although NT1 (IVS 1) mutation was increased and NT110 (IVS 1) mutation was decreased when compared with the findings in other Mediterranean populations. CONCLUSION: Due to historical reasons, the racial characteristics of Spanish people are the product of different ethnic groups, so hereditary disorders are here usually heterogeneous. This study appears to confirm such fact with respect to beta-thalassaemia.

Genetic Heterogeneity↗
PubMed1993

[The usefulness of the bcr/abl rearrangement in the diagnosis and evolution of chronic myeloid leukemia].

BACKGROUND: The rearrangement of the bcr/abl gene constitutes the molecular substrate of the Philadelphia chromosome (Ph'). The aim of this study was to analyze the usefulness of bcr/abl rearrangement in the diagnosis and evolution of chronic myeloid leukemia (CML). METHODS: The rearrangement of the bcr/abl gene was studied in 81 cases of which 34 corresponded to patients with CML (29 Ph' positive chromosome, 2 Ph' negative chromosome and 3 without karyotype), 2 patients with Ph' positive acute lymphoblastic leukemia, 15 patients with chronic myeloproliferative syndromes different from CML and 30 controls. Of the patients with CML, 6 were reevaluated when a blastic crisis was developed, 2 after receiving interferon treatment and 1 following allogeneic bone marrow transplantation. The technique used was that of Southern blotting using the restriction enzymes Bgl II and BamHI and the transprobe. RESULTS: Rearrangement of the bcr/abl gene was observed in all the patients with CML except in one with Ph' negative chromosome. In the remaining cases bcr/abl rearrangement was not observed. CONCLUSIONS: The Southern blotting technique for the study of the bcr/abl gene rearrangement is a sensitive and specific method in the diagnosis of chronic myeloid leukemia constituting a valid alternative to chromosomic study when this cannot be carried out or is not conclusive. It may also be used for the control of treatment in chronic myeloid leukemia.

Adult↗
PubMed1993

Usefulness of the rearrangement of the bcr/abl gene in extramedullary (lymph nodes) blast crisis diagnosed in chronic myeloid leukaemia.

The introduction of molecular biological techniques in the study of chronic myeloid leukaemia (CML) allows us to show the bcr/abl gene rearrangement produced by the translocation between the c-abl proto-oncogene located in chromosome 9 and the bcr region located in chromosome 22, which constitutes the molecular alteration of Philadelphia chromosome in CML. We present the usefulness of the bcr/abl gene rearrangement study in the diagnosis of a blast crisis initially located in lymph nodes of a patient with CML. The DNA analysis allows demonstration that the lymph node neoplastic cells originate from the clone responsible for the CML, while obtaining metaphases from a lymph node for the cytogenetic study gives rise to enormous difficulties and is practically impossible if the problem is studied retrospectively based on frozen or fixed samples.

Blast Crisis↗
PubMed1993

[Application of 2 electrophoresis techniques to the analysis of erythrocyte membrane proteins in hereditary spherocytosis].

Seven patients with hereditary spherocytosis have been studied using polyacrylamide gel electrophoresis with sodium dodecylsulfate (PAGE-SDS) and cytopherometry, in order to obtain information about possible alterations in the erythrocyte membrane proteins and in the electrophoretic mobility of whole erythrocytes. In four patients, a decrease in Band 4.2 protein was found. Histogram plotters proved of interest in showing two subpopulations in two patients. In all the cases, the electrophoretic mobility was normal. In two patients a spectrin deficiency was found. The study of histograms showed the presence of two subpopulations in this group of patients, in which the electrophoretic mobility was normal. Finally, one patient showed no deficiencies in membrane proteins. This fact can be due to an abnormality of spectrin that we could not detect with our techniques.

Blood Protein Electrophoresis↗
PubMed1993

[The first case of thalassemia intermedia in Spain due to the interaction of 3 alpha genes with beta-thalassemia minor].

We have identified the case of a 9-months-old girl with heterozygotic thalassemia and triplication of alpha genes of globin (alpha alpha alpha 3.7). Molecular defect of thalassemia was a mutation without sense of 39 codon. Patient's phenotype was an intermediate thalassemia with moderate splenomegaly and marked unbalance on the globin chains. This is the first case of intermediate thalassemia, through this mechanism, described in Spain.

Female↗
PubMed1992

[Second neoplasms as a late complication of the treatment of Hodgkin's disease].

PURPOSE: To determine the incidence of a second malignancy in patients with Hodgkin's disease (HD) diagnosed and treated in the same hospital. PATIENTS AND METHODS: A retrospective study was performed on 99 patients diagnosed and treated for HD in the Hospital San Carlos, in Madrid, between January 1976 and december 1987. The clinical records were revised; the diagnosis and staging followed the Rye and Ann Arbor criteria, and the treatment included radiation therapy (RT), chemotherapy (CT), or a combination of both. The diagnosis of the second malignancy was based upon clinical, analytical, radiological and histological records. RESULTS: The median age in the series was 31 years (16-82) and the M/F ratio was 61/38. The stage distribution was: I-9; II-29; III-31, and IV-30. Twenty-six patients received RT alone, 59 were treated with CT, and 14 received RT plus CT. A second neoplasm was found in 6 patients (6%), of whom 4 developed a myelodysplastic syndrome (MDS) and 2 a solid tumour. All the patients who had MDS had received MOPP or C-MOPP chemotherapy, associated in two of them with extensive RT. Both patients with solid tumour had been given CT+RT. The median time of presentation of the second malignancy since the diagnosis od HD was 89 months (48-174) for MDS and 120 months for the solid tumours. The four MDS patients have died, 2 for ANLL-M5, one for SRA and the remainder for cerebral haemorrhage, not yet evolved into acute leukaemia. The two patients which solid tumours are alive and seemingly in complete remission at 12 and 10 months, respectively, of the diagnosis of the second malignancy. CONCLUSIONS: 1) All the patients with second neoplasms had been previously treated with CT (MOPP or C-MOPP) or CT+RT. 2) Non-Hodgkin's lymphoma has not appeared in any of the patients in this series. 3) An endless follow-up of patients with HD seems important in order to achieve an early diagnosis of other malignant complications which, although in case of MDS have poor prognosis, in case of solid tumours may do well with adequate treatment.

Adolescent↗
PubMed1991

Unusual translocations and other changes in acute leukemia.

We report three cases of ANLL and one case of ALL in which we found chromosome abnormalities not previously described. The first patient had a (9;11;16)(p22;q23;p13) translocation in the relapse after bone marrow transplantation. In the second case, a secondary leukemia following a Wilms' tumor, there was a single chromosome anomaly, an inversion of chromosome 13. The third case also presented an isochromosome 13q. In the fourth patient we observed a translocation between two achrocentric chromosomes, as in the third patient, but not of the Robertsonian type: t(21;21)(q22.1;q22.5).

Adolescent↗
PubMed1991

[The successive presence of acute lymphoblastic leukemia, Hodgkin's disease and acute myeloblastic leukemia in a female patient].

A case is presented of a female patient initially diagnosed of acute lymphoblastic leukemia who was treated achieving complete remission. Twenty six months later and while in remission of her leukemia, she presented an abdominal mass the histological study of which showed infiltration due to Hodgkin disease. She was treated with chemotherapy type MOPP and complete remission was achieved. Four months after completing treatment she presented pancytopenia in peripheral blood. A bone marrow study was performed observing a blastoid infiltration with morphological and cytochemical characteristics of acute non-lymphoblastic M-5 leukemia. The possible common origin of the three clinical pictures is discussed given the recent findings regarding the origin of Reed-Sternberg cell.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Antibody-independent inhibition of Plasmodium falciparum in vitro cultures.

The sera of 100 Colombian individuals of African origin living in a malaria-endemic area of the Pacific coast were studied with regard to their capacity to inhibit Plasmodium falciparum cultures in vitro. Antimalarial antibody levels determined by indirect immunofluorescence were higher in the group of infected individuals than in the noninfected individuals, and inhibitory activity assessed by the inhibition of parasite incorporation of 3H-hypoxanthine in vitro was present in the sera of both the infected and noninfected patients. We believe that the noninfected patients were probably immune. The sera of some of the infected patients had high inhibitory capacities for the P. falciparum FCB-1 isolate. When the inhibitory effects of some of the sera were tested by using four parasite isolates from different regions of the world, striking differences among them were found.

Adolescent↗
PubMed1990

Hb O Padova in a Spanish Family.

Haematological and biochemical aspects of a new family with heterozygous Hb O Padova [alpha 30(B11) Glu----Lys] is described. This variant has been found on a screening programme of abnormal haemoglobin in cord blood. It was separated by cellulose acetate, isoelectric focusing, citrate agar, DEAE-cellulose chromatography and by cation exchange high-performance liquid chromatography. The heat stability and the functional properties were found to be normal. This is the third family with Hb O Padova reported, all from the Mediterranean region.

Amino Acids↗
PubMed1990

Hematologic data in 825 cases of beta-thalassemia trait in Spain.

We present the hematologic data of 825 cases of beta-thalassemia trait (687 cases of beta-thalassemia trait and 138 cases of delta beta-thalassemia trait). There were no significant differences between the red cell indices of the patients with beta and delta beta-thalassemia trait. In patients with beta-thalassemia trait, MCV was significantly reduced in 97% of the males and 99% of the females. All the patients with delta beta-thalassemia trait showed low MCV values. Red cell morphology was altered in the vast majority of cases, with basophilic stippling in 96% of the patients. Most patients came from provinces with the highest incidence of malaria in the past.

Adolescent↗