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Biomedical subjects

C Kattamis

Publications and source records attributed to C Kattamis.

At least 19 recordsLinked to original sources
PubMed2003

Efficacy and tolerability of formoterol Turbuhaler in children.

A randomised, double-blind trial was undertaken to investigate the efficacy and tolerability of formoterol Turbuhaler in children with mild to moderate asthma. After a two-week run-in, 248 children aged 6-17 years were randomised to receive formoterol 4.5 and 9 pmicro b.i.d. or placebo for 12 weeks. Morning PEF (primary variable), was significantly improved versus placebo only in the formoterol 9 pmicro b.i.d. group (13 l/min, 95% CCI 1.9, 24.2%; p = 0 .02). Both formoterol 4.5 and 9 pmicro significantly increased the pre-bronchodilator FEV1 by 5.2-6.7% (p < 0 .05) and reduced use of daytime relief medication versus placebo (p < 0 .05). Formoterol 9 pmicro significantly reduced night-time reliever use and awakenings due to asthma versus placebo (p < 0.05). Both doses of formoterol were as well tolerated as placebo. In conclusion, formoterol 4.5 and 9 micro b.i.d. is effective and well tolerated as maintenance therapy in children with mild to moderate asthma.

Administration, Inhalation↗
PubMed2001

Reactogenicity of DTPa-HBV/Hib vaccine administered as a single injection vs DTPa-HBV and Hib vaccines administered simultaneously at separate sites, to infants at 2, 4 and 6 months of age.

An open, randomised, multicentre trial was performed to assess the reactogenicity and safety profile of the administration of a candidate Haemophilus influenzae type b (Hib) conjugate vaccine with a quadrivalent diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HBV) vaccine as a single injection (Group 1) versus the simultaneous administration of the latter vaccine (DTPa-HBV) and an available Hib conjugate vaccine (Group 2) in opposite thighs, as a primary vaccination course to healthy infants at 2, 4 and 6 months of age. Eight hundred and eighty five infants (9.3+/-1.4 weeks old) were randomly allocated to Group 1 (n=665) and Group 2 (n=221). Oral polio vaccine was given concomitantly to all subjects. Blood samples (pre-vaccination and 1 month after the third dose) were obtained from a subset of infants (Group 1, 73; Group 2, 22) for serological determinations. Local and general symptoms were recorded by parents on diary cards. 2614 diary cards (Group 1, 1966; Group 2, 648) were collected. There were no statistically significant differences in the incidence of local and general symptoms between groups. Pain such that the infant cried when limb was moved was reported in 0.6 and 0.2% in groups 1 and 2, respectively. Redness and swelling (>20 mm in diameter) were recorded between 2.1 and 3% in both groups. Fussiness preventing normal activities was the most frequently reported general symptom in both groups (1.6 and 1.9% in groups 1 and 2, respectively). Fever (rectal temperature >39.5 degrees C) was reported in 0.4% (Group 1) and 0.3% (Group 2). All subjects included in the immunogenicity analysis had seroprotective or seropositive titres to the diphtheria, tetanus, hepatitis B and pertussis components of the vaccines. About 99 and 100% of infants had anti-PRP titres > or =0.15 mcg/ml in groups 1 and 2, respectively. This study indicates that DTPa-HBV vaccine given in a single injection with a candidate Hib conjugate vaccine has a similar reactogenicity profile to that of two commercially available vaccines (DTPa-HBV, Hib) given in two simultaneous injections to infants 2, 4 and 6 months of age.

Bacterial Capsules↗
PubMed2001

Variations of ferritin levels over a period of 15 years as a compliance chelation index in thalassemic patients.

We studied the changing pattern of the distribution of ferritin levels in 430 regularly-transfused patients with thalassemia in an attempt to evaluate compliance of chelation with deferoxamine. The study covered 15 years and was divided in three periods: 1981-1985, 1986-1990, and 1991-1995. The patients were stratified in age-groups. The mean ferritin levels of each period were calculated for each patient individually. The study showed that: (i) When all the patients were compared as a group, there was a significant decrease in mean ferritin between 1981-1985 and 1991-1995, despite a significant change in the patients' mean age; (ii) When patients of same age were compared between periods, there was a decrease in mean ferritin between 1981-1985 and 1991-1995, as well as a decrease in the proportion of patients with ferritin >4000 microg/L, with a parallel increase in the proportion of patients who had ferritin <2000 microg/L; (iii) When the same patients were followed longitudinally, they showed a decrease in their ferritin levels in all age groups with the exception of the late adolescence period. The decrease in iron overload observed in patients on close follow up implies that compliance with chelation therapy has improved with time and therefore, a favourable influence in survival could be expected.

Adolescent↗
PubMed2001

Different geographic origins of Hb Constant Spring [alpha(2) codon 142 TAA-->CAA].

BACKGROUND AND OBJECTIVES: The occurrence of Hb CS is usually limited to the geographic area which includes Southern China and South East Asia. In 1968 Hb CS was also found to occur in the Mediterranean area where it was originally described as Hb Athens. We investigated the independent origin of these termination codon mutations of the alpha 2-globin gene by determining the alpha-cluster haplotype and comparing the hematologic data from Hb CS-Hb H patients and their family members. DESIGN AND METHODS: We studied one Hb CS-Hb H patient of Greek origin and a Sicilian family in which one individual was affected by Hb CS-Hb H. The haplotype of the Hb CS allele was determined and compared to the haplotype of an Hb CS-Hb H individual of Chinese origin. RESULTS: The haplotype found for the Greek and Sicilian Hb CS was the same but differed significantly from the Asiatic Hb CS mutation. INTERPRETATION AND CONCLUSIONS: The Hb CS mutation found in both Mediterranean patients arose independently in the Mediterranean area. The difference in clinical manifestation of the Hb CS-Hb H disease in both patients is less common but consistent with similar variation in the clinical expression of analogous Hb Icaria-Hb H disease patients.

China↗
PubMed2000

Non-invasive myocardial iron assessment in thalassaemic patients. T2 relaxometry and magnetization transfer ratio measurements.

PURPOSE: To compare T2 relaxometry and magnetization transfer ratio (MTR) measurements of myocardial tissue in normal volunteers and thalassaemic patients for assessment of the myocardial iron levels. MATERIAL AND METHODS: All examinations were done on a 1 T MR system using a multi-echo spin-echo sequence with 8 echoes for T2 measurements and a gradient echo sequence for MTR measurements. Diastolic cardiac triggering was used in both sequences. Ten patients and 10 normal subjects were included in the study. T2 and MTR measurements were correlated with serum ferritin levels. RESULTS: Regression analysis between T2 and MTR measurements and ferritin demonstrated a reversed linear relationship, (r=-0.932, p<0.05) and (r= -0.824, p<0.05), respectively. Mean T2 relaxation time and mean MTR of the normal subjects (57.95+/-4.9 ms and 43.70+/-3.3%) was significantly higher than that of the thalassaemic patients (38.8+/-6.2 ms and 26.40+/-6.1%) (p<0.01), respectively. CONCLUSION: MTR measurements can be used to complement T2 measurements for non-invasive myocardial iron assessment.

Adult↗
PubMed2000

Molecular studies of beta-thalassemia heterozygotes with raised Hb F levels.

Hb F levels in beta-thalassemia heterozygotes are usually less than 2%, but amongst 1,059 patients studied, 73 (7%) had Hb F levels above 2.5% (2.6-14.0%). To investigate factors that may influence the increase of Hb F levels in these heterozygotes, we characterized the beta-thalassemia mutations and their chromosomal background, gamma-globin gene promoter variations, and alpha-globin genotypes. All 73 beta-thalassemia heterozygotes carried beta-thalassemia point mutations previously observed in the Greek population; gene mapping excluded b gene cluster deletions; only two cases had an additional gamma-globin gene (gammagammagamma/gammagamma). Five alpha-globin genes (alphaalphaalpha/alphaalpha) were detected in 17/73 cases (23%) as compared to a carrier rate of 1.76% in the general population. Molecular, hematological, and biosynthetic findings in these compound heterozygotes indicated that the raised Hb F levels were caused by cell selection due to ineffective erythropoiesis. In the remaining 56 simple beta-thalassemia heterozygotes, 11 beta-thalassemia mutations were observed, each on the expected haplotype(s), and analysis of the gamma gene promoters revealed three known polymorphisms (in linkage disequilibrium), with minimal influence on gamma-globin levels. However, the overall distribution of beta-thalassemia mutations in the 56 simple beta-thalassemia heterozygotes was significantly different (P<0.0002) compared to that in 986 simple beta-thalassemia heterozygotes with <2.5% Hb F, implicating an association between beta-thalassemia mutations and moderately increased Hb F levels, most notably codon 39 (C-->T), IVS-II-1 (G-->A), codon 6 (-A), and codon 8 (-AA), which accounted for 41/56 (73%) cases with >2.5% Hb F. In the remaining 15/56 (27%) cases, no common underlying globin genotypes could explain the raised Hb F levels. Overall, this study indicates that the control of Hb F levels in beta-thalassemia heterozygotes is heterogeneous and multi-factorial.

Chromosome Mapping↗
PubMed2000

Phenotypic and molecular diversity of haemoglobin H disease: a Greek experience.

Haemoglobin H (Hb H) disease is the severest form of alpha-thalassaemia compatible with post-natal life and occurs when alpha-thalassaemia mutations interact to reduce alpha-globin synthesis to levels approximately equivalent to the output of a single alpha-globin gene. Hb H disease has variable clinical expression, mainly related to underlying genotypes. The spectrum of alpha-thalassaemia determinants in Greece appears greater than in any other population studied and, in 75 Greek Hb H disease patients, we found 12 alpha-thalassaemia mutations interacting to produce 15 Hb H disease genotypes. Evaluation of haematological, biochemical and clinical findings, and correlation with genotypes, defined genetic predictors of disease severity and factors involved in disease progression. In accordance with previous reports, patients with non-deletion alpha-thalassaemia mutations had more severe clinical expression. Additionally, we found that all patients with the most severe phenotypes had alpha-thalassaemic globin variants. Phenotypic severity was not simply related to the degree of alpha-globin deficiency: high Hb H levels were found to exacerbate anaemia by negatively influencing tissue oxygenation, and both Hb H and alpha-thalassaemic haemoglobin variants appear to reduce red cell survival within the bone marrow and circulation. Together with the long-term follow-up in many patients, this report provides comprehensive information for management of Hb H disease and appropriate family counselling.

Adult↗
PubMed1999

Molecular, haematological and clinical studies of the -101 C --> T substitution of the beta-globin gene promoter in 25 beta-thalassaemia intermedia patients and 45 heterozygotes.

We report the clinical, haematological, biosynthetic and molecular data of 25 double heterozygote beta-thalassaemia intermedia patients and 45 beta-thalassaemia heterozygotes with the C --> T substitution at nucleotide position -101 from the Cap site, in the distal CACCC box of the beta-globin gene promoter. This mutation is considered the most common amongst the silent beta-thalassaemia mutations in Mediterranean populations. Of the 25 compound heterozygotes for the beta -101 C --> T and common severe beta-thalassaemia mutations, all but one had mild thalassaemia intermedia preserving haemoglobin levels around 9.5 g/dl and haemoglobin F levels < 25%. The only transfused patient was characterized to have an additional alpha-globin gene. Strict assessment of haematological and biosynthetic findings in the heterozygotes for the beta -101 C --> T mutation (excluding six cases with an alpha-globin gene defect) demonstrated that less than half of them had completely normal (silent) haematology; the remainder had either high haemoglobin A2 values (in the range of 3.7-5.1%) and/or low red cells indices and/or raised haemoglobin F values. The alpha/non-alpha-globin chain synthesis ratios were generally raised, with mean 1.44 (1.07-2.10). Amongst the parents of the compound heterozygotes, who were not selected for molecular analysis following haematological screening, half of the cases were completely silent. Interaction with severe beta-thalassaemia mutations always resulted in the clinical phenotype of mild non-transfusion-dependent thalassaemia intermedia.

Adolescent↗
PubMed1999

Hb Aghia Sophia [alpha62(E11)Val-->0 (alpha1)], an "in-frame" deletion causing alpha-thalassemia.

In this report we describe a case of Hb H disease due to the interaction of the --(MED 1) deletion with a new alpha(+)-thalassemia determinant. The molecular analysis of the proband's genomic DNA was carried out by polymerase chain reaction amplification and sequencing of both alpha genes of the alpha(+)-thalassemia chromosome and revealed a deletion of codon 62 of the alpha1 gene. This DNA triplet codes for a valine residue at the E11 alpha helix, which is located in the interior of the heme pocket. Substitutions of valine E11 with other amino acid residues in the alpha as well as beta polypeptide chains lead, in the heterozygous carrier, either to Hb M disease or to congenital non-spherocytic hemolytic anemia. We assume that the deletion of valine at alpha62(E11) disrupts the conformation of the alpha chain to such an extent that the mutated subunit is rapidly removed by proteolysis. The final result is an alpha-thalassemia phenotype rather than an unstable hemoglobin syndrome. This conclusion is supported by the apparent absence of an abnormal alpha chain in the peripheral blood of the patient.

Child, Preschool↗
PubMed1998

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↗
PubMed1998

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↗
PubMed1998

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↗
PubMed1998

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↗