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Biomedical subjects

B Dallapiccola

Publications and source records attributed to B Dallapiccola.

At least 307 records · Page 17Linked to original sources

Digeorge anomaly associated with partial deletion of chromosome 22. Report of a case with X/22 translocation and review of the literature.

Partial monosomy of 22q, resulting from a de novo unbalanced translocation t(X;22)(q28;q11) was detected in a newborn female with manifestations of the DiGeorge anomaly including multiple anomalies, type I truncus arteriosus, T-cell abnormalities, thymic aplasia and parathyroid hypoplasia noted on postmortem examination. Although DiGeorge anomaly is causally heterogeneous, our patient, together with 18 previously known cases, confirm that partial monosomy of the proximal long arm of chromosome 22 is the single most common cause of this polytopic developmental field defect.

Chromosome Deletion↗

Tetraploidy (92,XXYY) in an acute nonlymphocytic leukemia (M1) patient following autologous bone marrow transplantation.

Tetraploidy (4n = 92) without structural chromosome aberrations was found in bone marrow cells of a patient with acute nonlymphocytic leukemia, FAB classification M1, following autologous bone marrow transplantation. This finding, which remained undetected during the remission phases and appeared at relapses, progressed to a hypotetraploid modal number (74 chromosomes) at the terminal phase of the disease. Together with two previous observations in patients with acute lymphoblastic leukemia with L2 morphology and a null cell immunotype, this observation supports the hypothesis that tetraploid karyotypes may represent unusual and aspecific patterns of clonal evolution.

Adult↗

The phenotype of partial dup(7q) reconsidered: a report of five new cases.

Five unrelated patients with partial trisomy 7q are described. In two of them the duplicated region was 7q21----qter and in the others 7q22----qter, 7q34----qter and 7q35----qter, respectively. Clinical features were compared with those reported in published cases. Karyotype-phenotype correlations showed a relationship between the size of the unbalanced region and the survival, and prenatal and postnatal growth. In contrast, the same proportionality was not demonstrated between the severity of dysmorphic features and the size of the duplicated region. However, cleft palate seemed associated rather characteristically with dup 7q22/31----qter.

Abnormalities, Multiple↗

Gene dosage studies regionally assign the phosphoserine phosphatase gene to 7p15.1 or 2.

Gene dosage studies in subjects with imbalances of the short arm of chromosome 7 have suggested the localization of the phosphoserine phosphatase (PSP) structural gene to p22.1----pter or p15----p21.2. We have found normal enzyme activity in the fibroblasts from a patient with dup (7) (p15.3----pter). This result refines the assignment of the PSP gene to the 7p15.1----p15.2 sub-bands.

Chromosome Mapping↗

Protocol for prenatal diagnosis of cystic fibrosis based on studies of alkaline phosphatase isoenzymes.

Amniotic fluid analysis of microvillar enzymes, including alkaline phosphatase (ALP) total activity and ALP isoenzymes, has been widely experimented with and used for the prenatal diagnosis of cystic fibrosis in the second trimester of gestation. Since the development of cystic fibrosis molecular analysis, interest in these biochemical tests has been maintained for those instances in which the pregnancy is not fully informative by restriction fragment length polymorphism analysis or DNA is not available from the index-affected child. However, recommended biochemical protocols do not provide clear-cut diagnostic results in a minority of cases. We have tested the reliability of cystic fibrosis biochemical prediction by ALP high-resolution electrophoresis and ALP kinetic studies after inactivation by urea. With this approach, all the amniotic fluid samples that had not been unambiguously classified as affected or unaffected by standard microvillar enzymes analysis were definitely categorized. The proposed method seems to improve the diagnostic accuracy in pregnancies with a one in four risk of resulting in a child with cystic fibrosis.

Alkaline Phosphatase↗

Common fragile sites: their prevalence in subjects with constitutional and acquired chromosomal instability.

Chromosomal fragile sites that are inducible by methotrexate and aphidicolin are frequent in the human population. To assess the frequency and distribution of these common fragile sites, we performed a cytogenetic survey on lymphocytes from subjects known to be particularly prone to breakage because of constitutional chromosomal instability, the possession of a rare fragile site, or Fanconi anemia. Furthermore, a group of cancer patients was included in this study in view of possible acquired chromosomal instability. Lymphocyte chromosomes from several healthy donors were analyzed under identical conditions. We found that methotrexate- and aphidicolin-induced fragile sites are widespread in the general population, showing a similar breakpoint distribution. Ten fragile sites (3p14, 16q23, 2q32, 6q25, 4p16, 4q31, 14q24, 1p31, 20p12, 7q21) were observed in at least 40% of the individuals among the different groups. Our data point out a significantly increased breakage induced by aphidicolin in lymphocytes from cancer patients and, to a lesser extent, from rare fragile sites carriers. These results suggest that common fragile sites are enhanced in some constitutional and acquired conditions.

Adenocarcinoma↗

First trimester studies of a fetus at risk for triose phosphate isomerase deficiency.

A first trimester prenatal diagnosis was offered to a mother whose child had died of haemolytic anaemia and multisystem disease caused by TPI deficiency. The deficiency state was characterized by greatly reduced TPI activity in both erythrocytes and peripheral lymphocytes. Specific activity of TPI in trophoblast homogenates from the index fetus was about 30 per cent less than in the controls, but the heat stability test showed overlap. These data were confirmed in uncultured and cultured amniotic cells, where glycolytic intermediate concentrations DHAP, GAP and FDP fell in the range of controls. These results suggested that the fetus was a TPI heterozygote. This prenatal prediction was confirmed by RBC and haematological studies at birth.

Amniocentesis↗

Pathologic features in two siblings with the Pena-Shokeir I syndrome.

Two siblings whose clinical and pathologic features were consistent with the "Syndrome of camptodactyly, multiple ankyloses and pulmonary hypoplasia" originally described by Pena and Shokeir were examined at autopsy. Additional features were intrauterine growth retardation, immaturity of the central nervous system (CNS) and atrophy of skeletal muscles. Our data suggest that CNS damage may cause the complicated phenotypic abnormalities of the syndrome.

Abnormalities, Multiple↗

Cytogenetics of Mendelian mutations associated with cancer proneness.

About 5% of Mendelian mutations displaying neoplastic tendencies are associated with chromosomal aberrations. The best established examples are retinoblastoma and del(13)(q14) and aniridia-Wilms' tumor and del(11)(p13). Evidence suggests that both mutations behave as dominant traits in the individual and as recessive traits in the cells. DNA analysis indicates that tumorigenesis arises from homozygosisty for the mutant allele at these loci, as a consequence of mitotic nondisjunction or from a mitotic recombination event. An additional argument for this conclusion is provided by the demonstration of duplication of 11p15 in some patients with the Beckwith-Wiedemann syndrome, which is complicated often by Wilms' tumor and other embryonal tumors. Data obtained with molecular probes have shown that also rhabdomyosarcoma and hepatoblastoma arise by homozygosity for a mutant allele at a locus on 11p, suggesting ontogenic relatedness of these tumor types. Additional examples of Mendelian mutations associated with chromosome deletions and neoplasia include Langer-Giedion syndrome with multiple exostoses and del(8)(q24.1), multiple endocrine neoplasia and del(20)(p12.2). While the presence of specific chromosome changes in subjects with high susceptibility to neoplasia does pinpoint the location of DNA sequences involved in the predisposition to certain types of cancers, selected Mendelian mutations associated with chromosome instability and cancer proneness may elucidate biological principles of cell proliferation and transformation. However, our current knowledge of mechanisms resulting in increased frequency of chromosome breakage and cancer susceptibility in ataxia-teleangiectasia, Fanconi's anemia, Bloom's syndrome, and similar conditions are still very incomplete.

Chromosome Aberrations↗

Breakpoint distribution in constitutional chromosome rearrangements with respect to fragile sites.

In an attempt to investigate possible relationships between fragile site bands and chromosome abnormalities, we have analysed the distribution of 6391 breakpoints found in constitutional rearrangements. Were relative band lengths to be ignored, a general trend for breaks to be located in fragile site bands would be confirmed. On the other hand, no difference was detected between bands with or without fragile sites if the probability of breakage for each single band is assumed to be proportional to its length. Nevertheless, a number of bands with a great excess of breakage events were identified.

Analysis of Variance↗

Ring 20 chromosome phenotype.

A baby with a 46,XY,r(20) karyotype is described. The distinguishing features of this rare chromosome anomaly are analysed in the light of the suggested r(20) syndrome.

Abnormalities, Multiple↗

Alkaline phosphatase expression in human chorionic villi.

The physicochemical properties and electrophoretic mobility of different isoforms of alkaline phosphatase were studied in chorionic villi. Based on selective inactivation and inhibition studies (thermal stability, inactivation by urea, EDTA and L(+)ascorbic acid and L-amino acid inhibition), evidence was obtained for the existence of two distinct types of alkaline phosphatase in trophoblast cells. One type is peculiar to chorionic villi while the other is also found in term placenta. Both show two isoforms. These two isoforms were observed with polyacrylamide gel electrophoresis, carried out at pH 6.0 and 9.5. It is suggested that the qualitative and quantitative methods of alkaline phosphatase analysis could be used for first trimester fetal diagnosis of severe infantile hypophosphatasia and for understanding genetic control during early fetal development.

Alkaline Phosphatase↗

Ring chromosome 21 in healthy persons: different consequences in females and in males.

A stable ring chromosome 21 was found in an azoospermic man with an otherwise normal phenotype. Meiotic studies in another known azoospermic male with r(21) had indicated that breakdown of spermatogenesis resulted from pairing failure of chromosome 21, followed by degenerative changes in the chromosomes, before the cells had completed the first meiotic division. While primary sterility was a constant feature in the three adult males, eight healthy females with r(21) were fertile. However, they were at risk for Down syndrome and spontaneous abortions.

Adult↗