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Öğe Determination of Allelic Deletion of Multiple Endocrine Neoplasm Type 1 (MEN1) Gene in Acute Myeloid Leukemia (AML) by Application of FISH-TSA Technique(Wiley-Liss, 2002) Acar, Hasan; Kaynak, Murat; Yakut, Tahsin; Uçar, Fahri; Egeli, ÜnalWe have used the single and dual color fluorescence in situ hybridization (FISH) technique combined with a new detection system, tyramide signal amplification (TSA), by using the multiple endocrine neoplasm type I (MEN1) gene and chromosome I I specific alpha satellite DNA probes for the study of the allelic deletion of the MEN1 gene. The MEN1 gene is a new tumor supressor gene and has been recently cloned on chromosome 11q13. FISH combined with the TSA detection system was performed on bone marrow interphase nuclei of 22 patients with acute myeloid leukemia (AML). The FISH-TSA analysis revealed the mono allelic deletion of the MEN1 gene in 4 out of 22 patients (18.18%), 2 of 9 AML-M2 patients (22.2%), 1 of 6 AML-M4 patients (16.6%), and I of 4 AML-M5 patients (25.0%). Our study indicates that allelic deletion of the MEN1 gene is not a major cause or a primary event in tumorigenesis of AML, although the long arm (q13 region) of chromosome 11 involves a chromosomal rearrangement in AML.Öğe Evaluation of Chromosome 8 and 11 Aneuploidies in Washings and Biopsy Materials of Bladder Transitional Cell Carcinoma(Elsevier Science Inc, 2003) Acar, Hasan; Kılınç, Mehmet; Yıldırım, M. Selman; Kaynak, Murat; Cenker, AliWe compared chromosome 8 and 11 aneuploidies on bladder biopsy tumor tissues and bladder washing samples of transitional cell carcinoma (TCC) and their relationship to tumor malignancy. Interphase fluorescence in situ hybridization (FISH) was applied to nuclei of washing material and biopsy samples of 17 patients with TCC. Incidence of cells having aneuploidy was clearly nonrandom from patient to patient. There was no significant difference in the incidence of aneuploid frequency for chromosomes 8 and I I between biopsies of bladder tumors and bladder washing samples (P > 0.05). For chromosome 8, incidence of disomic cells (having two signals) in grade III tumors was significantly lower than in grade 11 tumors of both washing samples (P = 0.004) and biopsy materials (P = 0.005), indicating a high frequency of aneuploidy. The incidence of nuclei with four or more than four signals of chromosome 8 was significantly higher in grade III tumors than in grade 11 tumors in washing samples (P = 0.031 and 0.003, respectively). Similarly, in biopsy material, the incidence of nuclei with more than four signals of chromosome 8 was significantly higher in grade III tumors than in grade 11 tumors (P = 0.004). For chromosome 11, in both washing samples and biopsy materials, the incidence of disomic cells (having two signals) in grade III tumors was significantly lower than that detected in grade 11 tumors (P = 0.031 and 0.014, respectively), indicating a high frequency of aneuploidy. In biopsy materials, the incidence of nuclei with three or four signals was significantly higher than that in grade 11 tumors (P = 0.014 and 0.012, respectively). These findings suggest that FISH analysis of bladder washing samples can be efffectively detected as genetic changes of bladder tumors. It might predict genetic progression of these tumors, which might be related to tumor stage, because higher stages of tumors showed a higher incidence of aneuploidies of chromosomes 8 and 11. (C) 2003 Elsevier Science Inc. All rights reserved.Öğe Hyperdiploid Karyotype in a Childhood MDS Patient(Blackwell Science Ltd, 2001) Acar, Hasan; Çalışkan, Ümran; Kaynak, Murat; Yıldırım, Mahmut Selman; Largaespada, Davıd A.We present a rare case of a paediatric myelodysplastic syndrome (MDS) with congenital anomalies (frontal bossing and premature closure of anterior fontanelle). The case showed the clinical and biological features of a refractory anaemia excess blasts (RAEB). Bone marrow (BM) cytogenetics demonstrated a hyperdiploid karyotype, with several numerical abnormalities and unidentified rearrangements. Fluorescence in situ hybridization (FISH) using chromosome specific alpha -satellite and whole chromosome-specific painting probes verified the hyperdiploid karyotype, and confirmed the origin of the unknown markers and rearrangements more reliably than would be possible using conventional cytogenetic techniques.Öğe Molecular Cytogenetic Detection of Meiotic Segregation Patterns in Sperm Nuclei of Carriers of 46,xy,t(15;17)(Q21; Q25)(AMER SOC ANDROLOGY, INC, 2002) Çora, Tülin; Acar, Hasan; Kaynak, MuratStructural chromosomal abnormalities in gonadal tissue represent an important category of parentally transmittable unbalanced chromosomal abnormalities to the offspring. A child with multiple anomalies was sent for cytogenetic analysis, and his karyotype was 46,XY,der(17)t(15;17)(q21; q25). This abnormality was transferred from his grandfather to his father and to the proband. In this family, 5 persons (1 female and 4 male) are the carriers of this abnormality. In this study, fluorescence in situ hybridization (FISH) on sperm nuclei of 4 male carriers was studied to determine the distribution of segregation patterns of the balanced translocation 15q;17q. The segregation results showed that the segregation products in the third carrier (the grandfather) were different, but they were not statistically significant. The segregation patterns in the other carriers were similar. Overall, 50.3% of the sperm nuclei (mean value for 4 carriers) analyzed were the result of alternate segregation; 36.9%, of adjacent I segregation; 9.0%, of adjacent 11 segregation; and 2.4%, of 3:1 segregation; the remaining 1.3% could be diploid sperm nuclei or of 4:0 segregation. Multicolor FISH analysis appears to be a rapid and reliable method for the direct analysis of segregation patterns in sperm nuclei of carriers of balanced reciprocal translocation, and it also provides interesting information for determining the possible risks for the offspring.
