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Biomedical subjects

A Serra

Publications and source records attributed to A Serra.

At least 217 records · Page 12Linked to original sources
PubMed1988

Long-term cytogenetic effects of antineoplastic treatment in relation to secondary leukemia.

Chromosome translocations are consistently present in leukemias and lymphomas and are likely to represent primary events in the development of these neoplasias. A study of conditions that predispose to leukemia could shed some light on the origin of these translocations and therefore help in clarifying their exact role in the process of neoplastic transformation. Based on this assumption, we studied a group of individuals treated with radiochemotherapy for previous lymphoma and who were at increased risk of developing a secondary leukemia. The group comprised 14 Hodgkin's disease patients, 11 non-Hodgkin's lymphoma patients, and 13 controls. The patients were in remission and had been off therapy for at least 6 months. Chromosomes were studied from phytohemagglutinin (PHA)-stimulated peripheral lymphocytes and from bone marrow cells by the direct method and after short-term cultures (72 hours). The latter were also exposed to 5-bromodeoxyuridine (BrdU). Metaphases were scored for chromosome breaks, gaps, and other rearrangements. The percentage of gaps and breaks was significantly higher in patients than in controls. The difference was induced by BrdU and was apparent in bone marrow cells, but not in peripheral lymphocytes. We conclude that individuals exposed to the action of mutagenic agents (radiochemotherapy) have an increased chromosome instability that could be related to their increased risk of developing a secondary leukemia.

Adolescent↗
PubMed1988

Significance of Q-wave regression after transmural acute myocardial infarction.

A total of 313 consecutive patients was studied to assess the prevalence and prognostic implications of Q-wave loss after transmural acute myocardial infarction. Heart catheterization, including single-plane left ventriculography and selective coronary arteriography, was performed before hospital discharge. After a mean follow-up of 65 (1 to 100) months, 34 patients (11%) lost their Q waves. The time interval from the acute event to the first electrocardiogram showing Q-wave disappearance was 14 (1 to 32) months. Peak creatine kinase value was significantly higher in patients who retained their Q waves than in those who lost them (1,121 +/- 813 vs 779 +/- 464 IU, respectively, p less than 0.05). Severity of coronary artery disease, as judged by the number of diseased arteries and the number of arteries with total or subtotal occlusion, was similar in both groups. However, patients showing Q-wave regression had lower left ventricular end-diastolic pressure, higher ejection fraction and fewer abnormally contracting segments than their counterparts (12 +/- 6 vs 15 +/- 7 mm Hg, p less than 0.05; 53 +/- 11 vs 44 +/- 14%, p less than 0.001; 1 +/- 1 vs 2 +/- 1 segments, p less than 0.001, respectively). In addition, no patient with normalized electrocardiogram presented with left ventricular aneurysm. Although differences in mortality, nonfatal reinfarction and new onset of angina between the 2 groups were not significant, congestive heart failure was prevalent among patients with permanent Q waves (23 vs 6%, p less than 0.05). Our findings suggest that Q-wave loss after AMI may be related to a smaller infarct size.

Cardiac Catheterization↗
PubMed1988

Circulating 'trophoblast' cells in pregnancy have maternal genetic markers.

A syncytiotrophoblast-associated antigen identified by the monoclonal antibody (McAb) H315 is detectable on the surface of a low proportion of peripheral blood cells in pregnant women, raising the possibility of a new approach to prenatal diagnosis of genetic disorders. We aimed at verifying the trophoblastic origin of H315+ cells and their use for prenatal diagnosis of beta-thalassaemia. H315+ cells were separated from the peripheral blood of pregnant women: the DNA obtained from these cells in two selected cases was shown to have genetic markers indistinguishable from those of the mother and definitely different from the fetus. Our results suggest that H315 antigen is expressed by maternal cells and that prenatal diagnosis on peripheral blood of the mother using H315 McAb is not feasible.

Antibodies, Monoclonal↗
PubMed1988

Distribution of Ha-RAS-1 proto-oncogene alleles in breast cancer patients and in a control population.

The frequencies of 13 different Ha-ras proto-oncogene alleles have been estimated in 92 breast cancer patients and 60 unaffected individuals. The Ha-ras alleles can be identified using a DNA restriction fragment length polymorphism (RFLP) closely linked to the 3' end of the gene, and are characterized by a different length due to a region of sequences repeated a variable number of times (variable tandem repeats, VTR). The statistical analysis of the data obtained shows that the frequency of alleles ranging between specific length limits is significantly higher in breast cancer patients than in controls. The same applies to specific genotypes bearing the aforementioned alleles. This suggests that the inheritance of these alleles may be associated with an increased risk of developing breast cancer.

Adult↗
PubMed1988

Meiotic recombination in the beta globin gene cluster causing an error in prenatal diagnosis of beta thalassaemia.

In the course of a prenatal diagnosis for beta thalassaemia by linkage analysis of restriction fragment length polymorphisms, a homozygous beta thalassaemia fetus was misdiagnosed as beta thalassaemia trait. Extensive studies of the polymorphic sites within the beta globin gene cluster in all the members of the family resulted in the conclusion that the paternal chromosome 11 of the newborn was different from that expected. Paternity was confirmed by HLA typing and blood group studies. The analysis of another polymorphic locus on chromosome 11 within the family was in agreement with the possibility of a crossing over between the two paternal chromosomes in a region 5' to the beta gene, previously indicated to contain a 'hot spot' area for recombination. This report underlines the risk of performing prenatal diagnosis using restriction polymorphisms 5' to the beta gene.

Diagnostic Errors↗
PubMed1988

Variability of the molecular defects corresponding to the presence of a Philadelphia chromosome in human hematologic malignancies.

By analyzing a total of 107 patients affected by chronic myelogenous leukemia (CML; chronic and blast crisis) or lymphoid and myeloid Philadelphia chromosome (Ph') positive acute leukemias, we have investigated the relationship between the molecular defect on the Ph' chromosome and the associated hematologic phenotype. As expected, approximately half of the Ph' positive acute leukemias showed a breakpoint on chromosome 22 falling outside the "breakpoint cluster region" (bcr) known to be involved in CML. Surprisingly, seven of 80 CML cases in chronic phase also showed rearrangements falling outside the bcr region. In two of these cases the breakpoint on chromosome 22 was mapped between 9 and 12 kb upstream to the bcr region. In another case, the breakpoint was located approximately 16 kb downstream to bcr. In the remaining four cases, the precise position of the rearrangement could not be localized with the available bcr probes. DNAs from patients with CML blast crises showed classical bcr rearrangements. No molecular changes were observed during the progression of the disease in six patients whose DNA from both a chronic and acute phase was available. Our results seem to indicate a greater degree of variability of chromosome 22 breakpoints in CML than previously observed, and the lack of additional rearrangements on the Ph' chromosome in CML blast crises with respect to chronic phase.

Adult↗
PubMed1988

Rhabdomyolysis, oedema and arterial hypertension: different syndromes related to topical use of 9-alpha-fluoroprednisolone.

Over a one year period we detected five cases of iatrogenic mineralocorticoidism secondary to topical application of creams containing 9-alpha-fluoro-prednisolone. Although the same product was involved in all cases, the clinical features differed and included two cases of myopathy and hypokalemic rhabdomyolysis, one of oedema and two of arterial hypertension. Discontinuation of treatment and administration of potassium supplements produced a rapid recovery and all patients remain well six months later.

Adolescent↗
PubMed1988

Delineation of specific beta-thalassemia mutations in high-risk areas of Italy: a prerequisite for prenatal diagnosis.

In this study, we defined by haplotype characterization combined with oligonucleotide hybridization or direct restriction endonuclease analysis the specific beta-thalassemia mutations in a representative sample of beta-thalassemia chromosomes from patients with homozygous beta-thalassemia originating from different parts of Italy. We characterized the mutations in 90% of the thalassemia chromosomes and found that three mutations, namely the beta(+)IVS 1-110, beta (0)-39 and beta(+)IVS 1-6 are prevalent in the Italian population. Most of the patients investigated were compound heterozygotes for two beta-thalassemia mutations, and only a few were homozygotes for one mutant. On the basis of these findings, we predict that prenatal diagnosis in this population would be feasible in most cases by fetal DNA analysis with the oligonucleotide method using a limited number of oligonucleotide probes selected after screening parents for the most common beta-thalassemia mutations. We have also devised a method based on hybridization with a mixture of two oligonucleotides that allows rapid and simultaneous screening of prospective parents for the two most frequent mutations in Italians, the beta(+)IVS 1-110 and beta(0)-39 mutants. This method may be applicable to prenatal diagnosis in cases at risk for the genetic compound of these mutations.

DNA Mutational Analysis↗
PubMed1987

A benign form of thalassaemia intermedia may be determined by the interaction of triplicated alpha locus and heterozygous beta-thalassaemia.

In this paper we report that the combination of a triplicated alpha globin locus with heterozygous beta-thalassaemia produces a clinical phenotype of thalassaemia intermedia in five Italian subjects from four unrelated families, while in two other cases the phenotype was thalassaemia minor. The haematological findings of the five patients were uniform, producing a benign form of thalassaemia intermedia, transfusion independent, with a long life expectancy. The pattern of inheritance of the two genetic determinants and the more pronounced beta/alpha globin chain imbalance, demonstrates that the genetic combination is indeed the cause of the phenotype. The pattern of restriction enzyme site polymorphisms suggests the presence of the beta IVS I 110 G----A mutation at least in three of these cases.

Adolescent↗
PubMed1987

Myotonic dystrophy and chromosome translocation segregating in the same family.

We report on a family segregating the myotonic dystrophy (DM) gene and a t(5;8) reciprocal translocation. The DM presented the characteristics typically seen in this disease, i.e. full penetrance, broad expressivity, apparent anticipation in successive generations, presence of a congenital form transmitted by a carrier mother. The family was uninformative for linkage studies with the Lutheran and Secretor loci. The concordance between DM and chromosome translocation in 8 out of 9 individuals at risk was apparently due to chance.

Adult↗