Regulation of glucose disturbances with glibenclamide in patients with thalassemia.
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Adolescent↗
Biomedical subjects
C Kattamis
Publications and source records attributed to C Kattamis.
Analysis of low density lipoprotein receptor gene mutations and microsatellite haplotypes in Greek FH heterozygous children: six independent ancestors account for 60% of probands.
This study reports the characterization of 60% of low density lipoprotein receptor (LDLR) gene mutations in 150 unrelated Greek familial hypercholesterolaemia (FH) heterozygous children by the analysis of six LDLR gene mutations. The linkage disequilibrium of two polymorphic microsatellites (D19S394 and D19S221) flanking the LDLR gene on chromosome 19 to the four most common mutations strongly suggests that each mutation is identical-by-descent in the probands included in this study (this is also supported by the geographical distribution of FH families with these mutations throughout Greece) and permits an estimation of the number of generations from a common ancestor for each mutation. The characterization of 60% of LDLR mutations in a representative sample of Greek FH heterozygotes provides a basis for the diagnosis of FH through DNA analysis in Greece, by using single-strand conformation polymorphism analysis followed by allele-specific oligonucleotide hybridization (exon 6 mutations) or restriction endonuclease analysis (C152R, V408M). A rapid diagnostic assay positive for the mutation has been developed for the most common mutation, G528D. The application of simple DNA diagnostic assays for LDLR mutation analysis are appropriate for the early identification of FH heterozygotes in Greece and are useful for the primary prevention of coronary artery disease.
Adolescent↗
Molecular, haematological and clinical studies of a silent beta-gene C-->G mutation at 6 bp 3' to the termination codon (+1480 C-->G) in twelve Greek families.
We report the clinical, haematological, biosynthetic and molecular data of 12 beta-thalassaemia intermedia patients and their heterozygous parents, all of whom carried a rare C-->G mutation at nucleotide position 6 3' to the termination codon (term. cd +6 C-->G) in the 3' untranslated region (3' UTR) of the beta-globin gene (+1480 C-->G). This mutation has been reported previously in a single beta-thalassaemia intermedia patient of Greek origin. The 12 patients of the present study had the clinical phenotype of mild non-transfusion-dependent thalassaemia intermedia, preserving haemoglobin levels around 9 g/dl and haemoglobin F levels <25%. All were compound heterozygotes for the +1480 C-->G mutation and common severe beta-thalassaemia mutations. The haematological parameters of heterozygotes with this mutation were within the normal range with the exception of a slightly raised alpha/non-alpha-globin chain synthesis (1.2-1.9). mRNA analysis demonstrated a 20-34% reduction in mRNA levels associated with the +1480 C-->G mutation compared to normal beta-globin alleles. These findings confirm that the C-->G mutation at position 6 3' to the termination codon is a mild beta-thalassaemia mutation causing slight reduction in beta-globin mRNA levels and beta-globin chain synthesis. It becomes clinically relevant when co-inherited with a severe beta-thalassaemia mutation in trans.
Adolescent↗
Cystic fibrosis mutation screening in CBAVD patients and men with obstructive azoospermia or severe oligozoospermia.
Congenital bilateral absence of the vas deferens (CBAVD) found in otherwise healthy infertile males, is associated with a high incidence of mutated cystic fibrosis transmembrane conductance regulator (CFTR) alleles, and is considered a genital form of cystic fibrosis (CF). The CF gene may also be involved in the aetiology of male infertility in cases other than CBAVD. The present study was undertaken to test the involvement of CFTR gene mutations in 14 CBAVD males and additionally in cases of male infertility caused by obstructive azoospermia (n = 10) and severe oligozoospermia (n = 3). The entire coding region of the CFTR gene was analysed using denaturing gradient gel electrophoresis (DGGE). The three allele (5T, 7T, 9T) polymorphic tract of thymidines in intron 8 (IVS8-polyT) of which the 5T allele acts as a mild mutation, causing reduced levels of normal CFTR mRNA due to deletion of exon 9, was also analysed. Of the 14 CBAVD cases, four (28.6%) were found to have mutations in both copies of the CFTR gene, six (42.8%) had one CFTR mutation, and in the remaining four (28.6%) no CFTR mutations were found. Of the 10 cases with obstructive azoospermia, three (30%) had one CFTR mutation and in the remaining seven (70%) no mutations were found. None of the three severe oligozoospermia cases carried a CFTR mutation. The frequency of the IVS8(5T) allele was 14.3% (4/28) for the CBAVD cases and 5% (1/20) for the obstructive azoospermia cases, none of the severe oligozoospermia males carried the IVS8-5(5T) allele. The data indicate that while there is a strong association between male infertility caused by CBAVD and mutations in the CFTR gene, cases of obstructive azoospermia without CBAVD also seem to be associated with CFTR gene mutations.
Cystic Fibrosis↗
Rare beta-thalassemia alleles in the Greek and Greek Cypriot populations.
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Alleles↗
An alpha-thalassemic hemoglobinopathy: homozygosity for the HB Agrinio alpha 2-globin chain variant.
This report describes the first case of homozygosity for the Hb Agrinio [alpha 29(B10)Leu-->Pro] alpha 2-globin gene variant (codon 29, CTG-->CCG) in a Greek patient. At 12 months of age, the proband presented with a marked hypochromic, microcytic anemia, a very low level of Hb H (< 2.5%), rare Hb H inclusions, and a balanced alpha/non-alpha biosynthesis ratio. The mother had hematological findings and globin biosynthesis consistent with heterozygous beta-thalassemia, but paradoxically, red cell morphology demonstrated very rare Hb H inclusions. The father had mild microcytosis and hypochromia. Analysis of alpha- and beta-globin genotypes demonstrated that the patient was homozygous for the highly unstable Hb Agrinio variant, caused by a T-->C mutation in codon 29 of the alpha 2-globin gene. At the age of 13 years, the proband had a clinical phenotype compatible with mild thalassemia intermedia with moderate anemia (Hb 7-8 g/dL), normal growth and development, slight splenomegaly, and minimal bone changes, while Hb H and inclusion bodies were not detected.
Genetic Carrier Screening↗
Effective detection of active HCV infection: HCV RNA carrier state in a context free of hepatitis symptoms.
HCV immunological assays have limited specificity due to considerable variability of genomic coding sequences. Accordingly, PCR RNA detection also shows variable incidence of HCV in a non-A, non-B (NANB) hepatitis context. We used in-house designed nested PCR applying primers from the 5' untranslated region in 150 thalassemic patients classified in four groups according to anti-HCV screening and glutamic-pyruvate transaminase (GPT) levels. Group A: anti-HCV+/high GPT levels; group B: anti-HCV+/normal GPT levels; group C: anti-HCV(-)+high GPT levels; group D: anti-HCV(-)+normal GPT levels. Viral incidence and concentration, both high in group A, decreased towards group D. Group C RNA incidence was unexpectedly high and, moreover, one control case proved HCV-RNA+. Compared with the Amplicor kit or primers were considerably more sensitive.
Adolescent↗
A high incidence of mutations in exon 6 of the low-density lipoprotein receptor gene in Greek familial hypercholesterolemia patients, including a novel mutation.
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Adolescent↗
Corticosteroid treatment of erythema multiforme major (Stevens-Johnson syndrome) in children.
UNLABELLED: The effectiveness of systemic corticosteroids in erythema multiforme major (EMM) is controversial. We therefore evaluated the efficacy of corticosteroids in the treatment of EMM in a prospective study of 16 children with EMM admitted to our department within 3 days from the onset of rash. Ten patients (group A) received bolus infusions of methylprednisolone (4 mg/kg/day) while six had only supportive treatment (group B). The early use of corticosteroids compared to supportive treatment resulted in: (1) significant reduction of the period of fever (4.0 +/- 1.9 vs 9.5 +/- 4.2 days P = 0.01); (2) reduction of the period of acute eruption (7.0 +/- 3.3 versus 9.8 +/- 3.0 days P = 0.08); and (3) milder signs of prostration. Complications were minimal in both groups. CONCLUSION: The early and short course of corticosteroids favourably influences the course of erythema multiforme major in children.
Adolescent↗
Characterization of more than 85% of cystic fibrosis alleles in the Greek population, including five novel mutations.
To completely characterize the spectrum of mutations in the cystic fibrosis transmembrane conductance regulator gene in Greek cystic fibrosis (CF) patients, we screened 500 CF chromosomes by denaturing gradient gel electrophoresis followed by direct sequencing. We identified 48 mutations, accounting for 85.6% of CF chromosomes. They included eight novel mutations, three of which we have described before and five (E822X, Y247X, 2752-26A-->G, 3152delT, and 2751 + T-->A), which are described in this report. The detection of such a high proportion of Greek CF mutations is important for improving prenatal and genetic diagnosis of CF in Greece.
Adult↗
Prenatal diagnosis of the thalassaemia syndromes by rapid DNA analytical methods.
Prenatal diagnostic strategies applied today are based mainly on polymerase chain reaction (PCR) analytical protocols. In Greece a wide range of mutations underlie the thalassaemic haemoglobinopathies, and consequently a variety of PCR-based methods are required to facilitate diagnosis of all potential abnormal genotypes. PCR protocols include those which are relatively simple and others that are technically challenging, but very few have been designed for high through-put clinical diagnostics. Over a period of 18 months we carried out prenatal diagnosis of 147 pregnancies (150 fetal samples) at risk for a wide range of haemoglobinopathies. This involved the precise characterization of parental genotypes and the subsequent analysis of fetal DNA samples. In this series, 18 different mutations in the alpha- or beta-globin clusters were identified. For the characterization of these mutations, five PCR-based protocols were selected: denaturing gradient gel electrophoresis (DGGE), amplification refractory mutation system (ARMS) PCR, restriction endonuclease analysis of PCR fragments, oligonucleotide hybridization and 'gap' PCR for detection of deletions. To avoid spurious diagnosis due to contamination of fetal samples, two additional methods were used to genotype polymorphic variable nucleotide tandem repeat (VNTR) regions of the genome in parental and fetal samples. Through analysis of the results we assess the advantages and drawbacks of the selected PCR-based protocols for providing routine clinical diagnostics.
Alleles↗
Hib-EuroSud'95: the South exists.
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Greece↗
The interaction of alpha zero thalassaemia with Hb Icaria: three unusual cases of haemoglobinopathy H.
The clinical, haematological, biosynthetic and molecular data of three Greek haemoglobin H (HbH) disease patients with a distinctive clinical phenotype are described. During infancy all three patients had unusually severe clinical manifestations for HbH disease, with anaemia necessitating blood transfusions, signs of bone changes, growth impairment, and splenomegaly. Molecular analysis identified a rare alpha-thalassaemia genotype (--Med/ alpha Ic alpha). Splenectomy resulted in marked amelioration of the clinical signs; post splenectomy all three patients preserve adequate haemoglobin levels (9-10 g/dl) with growth restored to normal. Despite the initial severe clinical phenotype in these patients, our experience indicates that splenectomy modifies the clinical course to that of mild thalassaemia intermedia. This observation should be considered carefully when giving genetic counselling to families carrying the rare Hb Icaria mutation and an alpha zero thalassaemia mutation.
Autoradiography↗
The triplicated alpha-globin gene locus in beta-thalassaemia heterozygotes: clinical, haematological, biosynthetic and molecular studies.
Excess alpha-globin chains play a major role in the pathophysiology of homozygous beta-thalassaemia. In beta-thalassaemia carriers a minor effect of alpha-globin chain excess is reflected in a minimal or mild anaemia without clinical symptoms. Factors that increase alpha-chain excess in heterozygotes are expected to accentuate the severity of the clinical and haematological phenotype. We report the clinical, haematological, biosynthetic and molecular data in three beta-thalassaemia heterozygotes with the rare interaction of homozygosity for alpha-globin gene triplication, and in 17 heterozygotes with a single additional alpha-globin gene. The three patients homozygous for the alpha-globin gene locus (anti 3.7 kb arrangement) had beta(0)-thalassaemia mutations and a diagnosis of thalassaemia intermedia, preserving haemoglobin levels around 7-8 g/dl. Of the 17 beta-thalassaemia heterozygotes (six children and 11 adults), 16 had severe beta-thalassaemia mutations interacting with an additional alpha-globin gene (13 with alpha alpha alpha anti-3.7 and four with alpha alpha alpha anti-4.2). Compared to simple beta-thalassaemia heterozygotes, they had lower haemoglobin levels and red cell indices, but higher alpha/beta biosynthesis, HbF levels and reticulocytes. Our results suggest that homozygous alpha-gene triplication interacts with a severe beta-thalassaemia mutation to cause an alpha-chain excess equivalent to that observed in homozygous beta-thalassaemia intermedia. In heterozygotes for severe beta-thalassaemia mutations with one additional alpha-globin gene, the alpha-chain excess causes a more pronounced degree of anaemia than is usually seen in simple beta-thalassaemia heterozygotes.
Adult↗
The impact of neocyte transfusion in the management of thalassaemia.
Transfusional iron overload leading to cardiopathy and other severe complications continues to be a major problem in chronically transfused homozygous beta-thalassaemia patients. It is well known that young red cells (neocytes) survive longer after transfusion and therefore may contribute to the extension of the intervals between transfusions. We evaluated the impact of neocytes in the total annual blood requirements and consequently the transfusional iron load in 18 thalassaemia patients. A two-period study comparing transfusions of standard red cells versus neocytes in the same group of patients was performed. Neocytes were harvested by density separation using the Neocel System. The method of preparation was simple with relatively low costs and required no special equipment. There was a significant difference (p < 0.005) in PK and MCV values of the neocyte and older red cell (gerocyte) fractions indicating that a good separation of the two populations was achieved. All patients had a reduction in blood requirements during the neocyte period. The total annually transfused red blood cells and concomitant iron blood load were significantly reduced (p < 0.001) by 20.2 +/- 9.1%. However, the response was variable. Seven of the 18 patients had a large reduction in blood consumption (24.8-34.8%), 9 others ranged between 10.7 and 21.6%, and in 2 the reduction was less than 10%. This reduction in blood requirements and in the transfused iron may change the chelation index resulting in more efficient iron chelation therapy and perhaps reduce the cost of the haemochromatosis therapy on a long-term basis. We conclude that the use of neocyte therapy using this system can benefit the majority of chronically transfused patients by reducing transfusional iron overload and related complications and may lead to a much better quality of life.
Adolescent↗
Gaucher disease: four families with previously undescribed mutations.
We describe four families with patients with type I Gaucher disease exhibiting previously undescribed mutations of the glucocerebrosidase gene. We found Cherokee Indian woman to have a G-->C substitution in cDNA nucleotide 354, predicting a lysine-->aspargine substitution in amino acid 79 of the processed protein. In a Greek family, we found an allele with a C-->T substitution in nucleotide 475 giving rise to an arginine-->tryptophan substitution at amino acid 120. In another non-Jewish European patient, we identified a C-->T substitution in nucleotide 1223, predicting a threonine-->methionine mutation in amino acid 369. We found two non-Jewish European children to have a C-->T mutation at nucleotide 1357, predicting termination at codon 414. Although siblings carry the same two glucocerebrosidase mutations, in these families as in others we noted considerable differences in severity of clinical manifestations. Finding the reason for these differences is an important goal in the study of Gaucher disease.
Adult↗
1342C mutation in Gaucher's disease.
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Adolescent↗
Mutation analysis of ten exons of the CFTR gene in Greek cystic fibrosis patients: characterization of 74.5% of CF alleles including one novel mutation.
To initiate the complete characterization of mutations in the CFTR gene in Greek cystic fibrosis (CF) patients, we screened 184 patients for six relatively common mutations (delta F 508, G542X, G551D, 621 + 1 G-->T, N1303K, W1282X) using allele-specific hybridization and, in addition, analyzed exons 4, 5, 7, 8, 10, 11, 17b, 19, 20 and 21 using the method of denaturing gradient gel electrophoresis (DGGE). Six mutations accounted for 65.9% of the CF alleles in Greek patients, of which the delta F 508 mutation had a frequency of 52.7%. A further 15 previously described mutations accounted for another 8.3% CF alleles and one previously undescribed mutation (3272-4A-->G) was found in one chromosome. The W1282X mutation was not detected at all. Thus, so far, we have identified 21 mutations in the CFTR gene in Greek CF patients, accounting for 74.5% of the CF alleles.
Alleles↗