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A Angius

Publications and source records attributed to A Angius.

At least 37 records · Page 2Linked to original sources
PubMed1997

[Does a genetic predisposition for infarction expansion exist? Evaluation of genetic polymorphisms of the renin-angiotensin system].

Aim of this study is to carry out a genetic analysis of polymorphisms of the renin-angiotensin system in a genetically homogeneous population, in patients with and without myocardial infarction (AMI) expansion and to evaluate the influence of non genetic, mechanical factors. The study was conducted on 299 patients with first AMI. Ecocardiography studies were performed on all patients on day 1 and 3 from the onset of AMI and before discharge. Eighty-four patients were excluded because of inadequate quality of echocardiograms and 215 (163 males, 52 females) were admitted. Of these, 157 had no evidence of AMI expansion (EXP-) while 58 had expansion (EXP+). DNA was extracted by standard methods from blood samples. Age and gender had no influence on AMI expansion. Anterior infarction (p < 0.000001) and Q-wave infarction (p < 0.00002) were found more frequently in EXP+. Peak of creatine phosphokinase was higher in EXP+ than in EXP- (p < 0.00001). The percent of patients treated with thrombolysis or with hypertension and/or left ventricular hypertrophy was not significantly different in the two groups. AGT MT235 polymorphism of angiotensinogen gene, I/D polymorphism of ACE gene and AT1 A1166C of AT1 receptor of angiotensin II were not significantly different in two groups. Stratified analysis showed that in patients with anterior AMI (n = 87), with a higher risk of AMI expansion, there is a significant difference (p < 0.02) in ACE genotype between EXP- and EXP+. Odds ratio assuming the dominant effect of I allele (II+ ID < DD) was 3.35 (confidence interval 1.41-7.56) with increased risk of expansion. More extension studies are need to verify if these results can contribute to early identification of patients at higher risk and to optimize therapeutic approach.

Aged↗
PubMed1996

Rh D/d genotyping by quantitative polymerase chain reaction and capillary zone electrophoresis.

A safe and reliable method for determining RhD type (positive or negative) and zygosity (D/D or D/d) could have applications, for instance, in the prediction of the D genotype of a father in couples where there is an RhD-negative woman at risk of fetal alloimmunization. Capillary zone electrophoresis (CZE) is proposed as a novel, reliable and powerful method for quantitative evaluation of polymerase chain reaction (PCR) products. RhD is determined by amplifying a 136 bp region common to the RhCcEe and RhD genes and a 186 bp region specific of the RhD gene. RhD positive and negative samples are identified by polyacrylamide gel slab electrophoresis, followed by silver staining of the DNA bands, and by CZE in sieving liquid polymers, with direct on-line peak densitometric evaluation by exploiting the intrinsic UV absorbance of the DNA fragments at 254 nm. The CZE method allows not only a reliable assessment of the RhD type (the presence of both 136 bp and 186 bp fragments indicating an RhD-positive type, the presence of only the 136 bp fragment indicating an RhD-negative type), but also a rapid determination of the zygosity based on the quantitative expression ratio of the 136 bp/186 bp pair. Thus, a 2:1 peak ratio clearly indicates a D/D homozygous individual, whereas a 3:1 peak ratio gives evidence of a D/d heterozygous individual.

DNA↗
PubMed1996

Wilson disease mutations associated with uncommon haplotypes in Mediterranean patients.

This study reports 12 novel mutations of the Wilson disease (WD) gene which have been detected by the molecular analysis of 29 patients of Mediterranean descent carrying uncommon chromosomal haplotypes at the WD locus. These mutations include two nonsense, one splice site and nine missense. The missense mutations lie in regions of the WD gene critical for its function, such as the transmembrane region, the transduction domain and the ATP loop and ATP-binding domain, indicating that they are disease-causing mutations. These new findings improve our knowledge for the role played by functional domains on the ATP7B function.

Albania↗
PubMed1995

Molecular pathology and haplotype analysis of Wilson disease in Mediterranean populations.

We analyzed mutations and defined the chromosomal haplotype in 127 patients and Mediterranean descent who were affected by Wilson disease (WD), 39 Sardinians, 49 Italians, 33 Turks, and 6 Albanians. Haplotypes were derived by use of the microsatellite markers D13S301, D13S296, D13S297, and D13S298, which are linked to the WD locus. There were five common haplotypes in Sardinians, three in Italians, and two in Turks, which accounted for 85%, 32%, and 30% of the WD chromosomes, respectively. We identified 16 novel mutations: 8 frameshifts, 7 missense mutations, and 1 splicing defect. In addition, we detected the previously described mutations: 2302insC, 3404delC, Arg1320ter, Gly944-Ser, and His1070Gin. Of the new mutations detected. two, the 1515insT on haplotype I and 2464delC on haplotype XVI, accounted for 6% and 13%, respectively, of the mutations in WD chromosomes in the Sardinian population. Mutations H1070Q, 2302insC, and 2533delA represented 13%, 8%, and 8%, respectively, of the mutations in WD chromosomes in other Mediterranean populations. The remaining mutations were rare and limited to one or two patients from different populations. Thus, WD results from some frequent mutations and many rare defects.

Albania↗
PubMed1994

Improvement of prenatal diagnosis of Wilson disease using microsatellite markers.

This paper describes a case of prenatal diagnosis for Wilson disease (WD) carried out in an at-risk couple of Sardinian descent, following non-directive genetic counselling. Diagnosis was obtained by using eight microsatellites located within or flanking the WD locus, six of which were 100 per cent and two 50 per cent informative. The use of several markers may limit the occurrence of misdiagnosis resulting from recombination or instability of repeats.

Child, Preschool↗
PubMed1983

Molecular mechanism accounting for milder types of thalassemia major.

We carried out alpha-globin gene analysis by restriction endonuclease mapping in 91 Sardinians with homozygous transfusion-dependent beta 0-thalassemia and correlated the clinical findings with the alpha-globin genotype. In patients (n = 6) with deletion of two alpha-globin structural genes, disease onset and transfusion dependence occur later than in those (n = 50) with a full complement of alpha-globin genes. There was no statistically significant difference in the group of patients (n = 35) with deletion of only one alpha-globin gene. Patients with deletion of two alpha-globin genes had significantly higher Hb A2 levels than those with a full complement of alpha-structural genes and those with deletion of a single alpha-globin gene. From this and other studies, it seems that the deletion of two alpha-globin structural genes may convert the common severe clinical picture associated with homozygous beta 0-thalassemia to milder forms, ranging from a later occurring but still transfusion-dependent type to a non-transfusion-dependent form.

Child, Preschool↗
PubMed1982

Haematological and obstetric aspects of antenatal diagnosis of beta-thalassaemia: experience with 200 cases.

The results of 200 antenatal diagnoses in pregnancies at risk for homozygous beta-thalassaemia, carried out on fetal blood samples obtained by placental aspiration in the second trimester, are described. Globin chain synthesis in the fetuses was measured by means of 3H-leucine incorporation and separation of the chains on carboxy-methyl-cellulose columns. Fetal red cell enrichment was performed by NH4Cl-NH4HCO3 differential lysis of maternal cells or anti-i differential agglutination. Sufficient fetal blood for analysis was obtained in 97.5% of the cases. The overall fetal loss rate was 6.5%, but it declined from 10% in the first consecutive 100 cases to 3% in the last 100 cases. Fetal loss was the result of early or late intrauterine death or spontaneous abortion. Forty-two homozygous fetuses had no beta-chain synthesis and one had a very low beta/gamma ratio (0.005). Of the pregnancies, 37 were terminated at parental request and four aborted spontaneously. Absence of beta-chain radioactivity was confirmed in 12 abortuses with suitable cord blood samples for analysis. Two pregnancies with homozygous fetuses were not terminated, as one member of each couple was a devout Catholic. As expected, both infants developed Cooley's anaemia. Follow-up of the 146 infants, diagnosed in utero as non-homozygotes, showed cerebral palsy in one and a small cutaneous needle injury in three. None of these developed homozygous beta-thalassaemia. Even beta-thalassaemia trait with a beta/gamma ratio of 0.046 +/- 0.012 can be distinguished from normal, showing a beta/gamma ratio of 0.086 +/- 0.019 with a high degree of certainty.

Abortion, Induced↗
PubMed1982

Delta beta (F)-thalassaemia in Sardinia.

A population survey carried out in southern sardinia on more than 5000 people has shown that delta beta (F)-thalassaemia, with a gene frequency of 0-00088, is a rare trait in this population. We examined the members of three families segregating for both delta beta- and beta(0)-thalassemia and a number of delta beta carriers identified during the screening. The doubly heterozygous children suffer from a mild form of Cooley's disease with non-alpha/alpha biosynthetic ratios within the range of values observed in beta (0)-thalassaemia homozygotes. Three of them have been transfusion dependent for some time. The delta beta carriers, although in many respects showing the usual picture of delta beta-thalassaemia, such as abnormal red cell indices, normal Hb A2, Hb F heterogeneously distributed in the erythrocytes, and low beta/alpha synthetic ratios, have unusually high levels of Hb F (range 10 to 20%) and particularly low glycine content (range 0.02 to 0.14 residues) in the isolated gamma CB3 peptide. These results have led us to the conclusion that the delta beta-thalassaemia found in Sardinia is different from the similar kind of delta beta defect found in Negroes and in other Mediterranean populations, including continental Italians.

Adolescent↗
PubMed1982

Alpha-thalassemia in two Mediterranean populations.

We used restriction endonuclease analysis to determine the incidence of alpha-thalassemia in two Mediterranean islands. In a random population sample, the gene frequency of deletion-type alpha-thalassemia-2 (-alpha) was 0.18 in Sardinians and 0.07 in Greek Cypriots. All cases were the rightward crossover type. From these frequencies and the known incidence of hemoglobin-H disease in these populations, we calculated the frequency of the alpha-thalassemia-1 genotype (--) and determined that it was low. We also found that beta-thalassemia homozygotes in sardinia have a higher incidence of alpha-thalassemia than normals and beta thalassemia heterozygotes because a significantly greater number of these homozygotes are also homozygous for the alpha-thalassemia-2 lesion. These findings support the theory that coinheritance of alpha-thalassemia mitigates the severity of beta-thalassemia and suggest that the protection is most pronounced when two alpha-globin genes are deleted.

Cyprus↗
PubMed1981

Beta-Thalassaemia types in southern Sardinia.

In this study the prevalence of the different beta-thalassaemia types in southern Sardinia was investigated by cellulose acetate and agar gel electrophoresis or globin chain synthesis analysis on column chromatography or both in (1) all the patients (347) presenting with thalassaemia major or intermedia at our haematology service from 1976 to 1979, and (2) a group of 82 patients with transfusion-dependent thalassaemia major randomly chosen from 236 under our care. Apart from six subjects with delta(beta)0/beta+-thalassaemia genotype and eight with beta0/beta+ or less probably beta+/beta/-thalassaemia, all thalassaemia major and intermedia patients studied were beta0-thalassaemia homozygotes. Globin chain synthesis on peripheral blood cells from these patients, performed at different intervals from blood transfusion, showed no incorporation of radioactive leucine into beta-globin peak, the same as before the transfusion. No correlation between kappa/gamma ratios and clinical severity or hypersplenism was found. Globin chain synthesis analysis carried out at birth in three infants later found to have homozygous beta0-thalassaemia demonstrated imbalanced or borderline kappa/gamma ratios.

Blood Transfusion↗
PubMed1981

Prenatal diagnosis of thalassaemia major resulting from Lepore/ beta-thalassaemia genotype.

Antenatal diagnosis was carried out in a pregnancy at risk for beta-thalassaemia major/intermedia, resulting from the Lepore/ beta-thalassaemia genotype, by globin chain synthesis analysis on fetal blood obtained by placentocentesis at 19 weeks' gestation. As there was no radioactive incorporation in the beta-region, the fetus was considered to be a Lepore/ beta-thalassaemia genetic compound and aborted on parental request. After abortion, cord blood analysis confirmed the absence of beta-chain radioactivity.

Female↗
PubMed1981

beta zero thalassemia in Sardinia is caused by a nonsense mutation.

We report the characterization of a molecular lesion of beta thalassemia in Sardinia. Beta thalassemia in this area is predominantly the beta zero type with low levels of beta-globin mRNA. Translation assay of this messenger RNA in a cell-free system showed beta-globin chain synthesis only with the addition of an amber (UAG) suppressor transfer RNA. Double-stranded complementary DNA prepared from reticulocyte mRNA from a Sardinian patient was cloned in a bacterial plasmid and a beta-globin complementary DNA containing clone was isolated and sequenced. At the position corresponding to amino acid number 39, a single nucleotide mutation converted a glutamine codon (CAG) to an amber termination codon (UAG). We previously reported an amber nonsense mutation at amino acid 17 as a cause of Chinese beta zero thalassemia. Thus, beta zero thalassemia in Sardinia represents the second example of a nonsense mutation, and we predict that other beta zero thalassemias with mutations at various points along the beta-globin chain will be found to form a discrete subgroup of beta zero thalassemia. These experiments further illustrate the heterogeneity of lesions that lead to defective globin chain synthesis in beta thalassemia.

Bacteriophage lambda↗
PubMed1981

Isoelectric focusing of globin chains for antenatal diagnosis of beta 0-thalassemia.

A recently developed isoelectric focusing technique for human globin chain separation has been applied to the antenatal diagnosis of beta 0-thalassemia in Sardinia. Results obtained with this method show a complete concordance with those obtained by the currently-in-use chromatographic separation of globin chains by carboxymethyl-cellulose. The ease with which several samples (up to 20) can be simultaneously processed and analyzed by a single operator and the very simple equipment required make this new method ideal for the antenatal diagnosis of beta 0-thalassemia and could encourage a more widespread use of prenatal diagnosis of thalassemias.

Anemia, Sickle Cell↗
PubMed1981

Diagnosis of the beta 0 thalassemia trait at birth.

This study shows the results of in vitro globin chain synthesis analysis in 33 infants who had been previously evaluated for the presence of thalassemia in the second trimester of gestation and were restudied after the stage of hematological maturity. Four children with alpha-thalassemia-1, identified in a newborn screening, were also included. Normals and beta-thalassemia heterozygotes could be distinguished in the neonatal period by beta/alpha or beta/gamma ratios. However, as a considerable overlap of alpha-thalassemia-1 with normals and alpha-thalassemia-2 with beta-thalassemia heterozygotes were found, biosynthetic studies at birth seem to be inappropriate to make reliable diagnosis of hemoglobin chain deficiencies. There were no differences between hematological indices of normal and heterozygous beta-thalassemia newborns, while alpha-thalassemia-1 carriers showed a statistically significant difference from normals in mean MCV and MCH.

Female↗