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G Balta

Publications and source records attributed to G Balta.

7 recordsLinked to original sources

Evidence for the existence of the PAF acetylhydrolase mutation (Val279Phe) in non-Japanese populations: a preliminary study in Turkey, Azerbaijan, and Kyrgyzstan.

Deficiency of plasma platelet-activating factor (PAF) acetylhydrolase resulting from a missense mutation (Val279Phe) in exon 9 of the gene has been described exclusively in the Japanese population with a very high frequency. This study describes the distribution of the mutation in Turkey and two other Turkic nations, Kyrgyzstan in central Asia and Azerbaijan bordering the Caspian Sea. Among 358 unrelated healthy subjects studied from Turkish population, only 3 had the mutation in heterozygous state (0.84%). Family studies also revealed the presence of homozygous individuals in close relatives of one of these subjects. Among 143 healthy subjects studied from Kyrgyzstan, 12 were heterozygous for the mutation (8.4%). No mutation was detected among 100 healthy individuals studied from Azerbaijan. However, it was suggested that the number of subjects was not enough to draw any conclusion about the prevalence of the mutation in the populations studied. Contrary to the previous notions, identification of the mutation in Turkey and Kyrgyzstan shows the existence of the mutation in non-Japanese populations as well.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗

Fanconi anemia A due to a novel frameshift mutation in hotspot motifs: lack of FANCA protein.

Homozygosity for a frameshift mutation at codon 1213 of FANCA gene was identified in a Turkish patient. Immunoprecipitation-western blot analysis showed the complete absence of the FANCA protein band. This novel mutation, a deletion of T at position 3639 in exon 37 (3639delT), is responsible for the disease and causes premature termination of translation 32 aa downstream. The deletion is (i) the T residue of 2 overlapping TGAGGC and CCTG hot spot motifs, (ii) flanked by several direct repeats, (iii) surrounded by the highly GC rich region that have frequently been identified at the site of human DNA deletions. The patient is the third living child of a first degree cousin marriage. The major abnormalities of the patient at the age of 6 months were growth retardation, microcephaly, hypoplastic right thumb, distal displacements of both thumbs and pelvic displacement of left kidney. Hematological presentation of the disease started before the age of 4 years.

Cell Cycle Proteins↗

Modified induction course: a solution to side-effects?

Side-effects are commonly manifested during intravesical Bacillus Calmette-Guérin (BCG) immunotherapy of superficial bladder cancer. This often causes delays or interruptions of the instillations and consequently reduces the efficacy of treatment. Treatment strategies aimed at reducing the side-effects of BCG immunotherapy while maintaining efficacy are currently being considered in the search for an optimal treatment regimen. The following two approaches to BCG immunotherapy were investigated at the Department of Urology of Padova University by specific Phase II and III trials designed to evaluate the possibility of reducing BCG-related side-effects without compromising therapeutic efficacy: (1) by reducing the dose of BCG per instillation 'low-dose' regimen, (2) by delaying the interval of the instillations 'slow-rate' regimen.

Administration, Intravesical↗

Increased expression of the G gamma and A gamma globin genes associated with a mutation in the A gamma enhancer.

We have previously described a unique type of delta beta-thalassemia in a Chinese family characterized by increased expression of the G gamma and A gamma fetal globin genes in the absence of a large deletion in the beta-globlin gene cluster. Our earlier study of the beta-globin gene on this delta beta-thalassemia chromosome showed a promoter mutation in the TATA box. In this report, we describe the results of our study of the fetal globin domain of this delta beta-thalassemia chromosome. We have cloned a 13-kb DNA fragment that includes the G gamma and the A gamma genes and the 3' A gamma enhancer element of this delta beta-thalassemia chromosome. DNA sequence analysis of the G gamma and A gamma-globin genes including their promoters did not show any mutations, but analysis of the putative enhancer element downstream from the A gamma-globin gene showed a C to T substitution 2,401 nucleotides downstream from the A gamma cap site. We performed DNA linkage analysis to determine if this mutation is unique to this chromosome or represents a common polymorphism. Our linkage analysis showed that this mutation is not a common polymorphism and that it is also not an intrinsic part of the haplotype of the chromosome on which it was found. We also studied the interaction of nuclear proteins from erythroid and nonerythroid cells with the DNA sequences surrounding this mutation. We have shown by in vitro DNase I footprinting that this mutation falls within a region that is occupied by a novel DNA-binding protein that binds to this site in nuclear extracts from erythroid, but not nonerythroid cells. The binding of this nuclear protein to DNA appears to be dependent on GATA-1 binding to an adjacent GATA-1 site. We have also developed a new functional assay to compare the activity of the normal and mutant A gamma enhancer elements in erythroid cells. Analysis of the activity of the mutant enhancer shows that the mutation completely eliminates all enhancer activity in this assay. These findings suggest that this mutation of the A gamma enhancer on a chromosome that carries a partially inactivated beta-globin gene may be responsible for the increased expression of both gamma-globin genes seen in this condition.

Base Sequence↗

Methylenetetrahydrofolate reductase (MTHFR) C677T mutation in Turkish patients with thrombosis.

Recently, the homozygote state for the thermolabile variant of the MTHFR gene (C677T) has been identified as a determinant of elevated homocysteine levels which are known to be a risk factor for arterial and thrombotic vascular disease. To determine whether this variant increases the risk of thrombosis, we analyzed the prevalence of the C677T substitution in the MTHFR gene in 94 patients with thrombosis and in 95 unmatched controls. Although homozygosity for the mutation was found in 12 (12.8%) of the patients with thrombosis and in only six (6.3%) of the control subjects, the difference in the prevalence of the homozygous mutant genotype between patients and healthy subjects was not statistically significant.

Case-Control Studies↗