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Biomedical subjects

Y Tunca

Publications and source records attributed to Y Tunca.

12 recordsLinked to original sources

A chronic myeloid leukemia-like syndrome case with del (12) (p12) in a Li-Fraumeni syndrome family.

Li-Fraumeni syndrome is a familial cancer syndrome characterized by different tumors and hereditary p53 mutations. Here, a chronic myeloid leukemia-like syndrome case in a Li-Fraumeni syndrome family with del (12) (p12) cytogenetic abnormality was presented. A hereditary p53 mutation (pro309ser) supported the Li-Fraumeni syndrome diagnosis in this family. This syndrome was characterized by the clonal myeloproliferative accumulation in bone marrow and peripheral blood with negative bcr/abl gene rearrangement finding. The etiology of this rare syndrome is still unclear. This is the only chronic myeloid leukemia-like syndrome case reported in a Li-Fraumeni syndrome family. Del (12)(p12) was observed in leukemias except chronic myeloid leukemia-like syndrome. The deletion in chromosome 12p12 with hereditary p53 mutation should have a critical role in chronic myeloid leukemia-like syndrome etiology in our case.

Chromosome Deletion↗

Long-term survival in Patau syndrome.

A female patient with an extra chromosome 13 (Patau syndrome) is described. There are only five previous reports of patients with trisomy 13 who have survived past the first decade. It is concluded that non-lethal congenital anomalies and aggressive medical care play an important role in the survival of patients with trisomy 13.

Abnormalities, Multiple↗

The effects of folic acid application on IL-1beta levels of human gingival fibroblasts stimulated by phenytoin and TNFalpha in vitro: a preliminary study.

Folic acid (FA), that is required for the integrity of gingival tissues, was found to decrease in patients using phenytoin (PHT). Interleukin-1 beta (IL-1beta) was reported to enhance the extracellular matrix synthesis in fibroblasts. The purpose of this study was to assess the role of FA supplementation on PHT-induced overgrowth by investigating its effect on IL-1beta production of human gingival fibroblasts induced by tumor necrosis factor alfa (TNFalpha) in cell culture. PHT (20 microg/ml), FA (20 or 40 ng/ml) + PHT, PHT + TNF (10 ng/ml), FA (20 or 40 ng/ml) + PHT + TNF, or only culture medium (control) was added to 24-well plates containing fibroblasts. After an incubation period of 72 h, culture medium and cells were harvested separately. Then, IL-1beta levels in cell lysate were measured using enzyme-linked immunosorbent assay. The cellular IL-1beta level in the PHT group was 1 pg/ml. In PHT + 20 or 40 ng/ml FA-added cultures, the results obtained respectively were 0.8 and 0.7 pg/ml, whereas the control group value was 0.7 pg/ml. IL-1beta level was 4 pg/ml in the cultures that PHT and TNFalpha were applied simultaneously (P < 0.05). When PHT and either 20 or 40 ng/ml FA were simultaneously added into TNFalpha-induced cultures, the IL-1beta levels were 1.8 and 1.3 pg/ml, respectively. IL-1beta level in gingival tissues might play a role in PHT-induced overgrowth by increasing in the gingival tissues, and FA application might play a role in decreasing gingival tissues. However, further studies are needed for a more complete understanding of PHT-induced gingival overgrowth at the cellular level.

Anticonvulsants↗

Localization of SRY by primed in situ labeling in XX and XY sex reversal.

Primed in situ labeling (PRINS) can be used to localize DNA segments too small to be detected by fluorescence in situ hybridization. By PRINS we identified the SRY gene in two XX males, a woman with XY gonadal dysgenesis, and an azoospermic male with Xp-Yp interchange. Because PRINS has been used generally in the study of repetitive sequences, we modified the technique for study of the single copy 2. 1-kb SRY sequence. SRY signals were identified at band Yp11.31p11.32 in normal XY males and in the woman with XY gonadal dysgenesis. SRY signals were identified on Xp22 in one XX male but not in the other. They were identified in the corresponding region (Xp22) of the der(X) in the azoospermic male with Xp-Yp interchange. SRY signals were not observed in normal XX females. Presence of SRY in DNA samples from the various subjects was confirmed by polymerase chain reaction. We conclude that PRINS is ideal for rapid localization of single copy genes and small DNA segments in general.

Adult↗

Chromosomal localization of single copy genes SRY and SOX3 by primed in situ labeling (PRINS).

Primed in situ labeling (PRINS) is a sensitive and specific technique that can be used for the localization of single copy genes and DNA segments that are too small to be detected by conventional FISH. With PRINS, we physically localized the SRY gene to Yp11.31p11.32 and the SOX3 gene to Xq26q27. Locus-specific oligonucleotide primers were annealed in situ and extended on chromosome preparations fixed on microscope slides, in the presence of dATP, dCTP, dGTP, dTTP, biotin-16-dUTP, Tris-HCl, KCl, MgCl2, BSA, and Taq DNA polymerase. Fluorescent signals were detected in metaphase spreads and interphase nuclei. Our method may prove valuable for use with single copy genes in general.

Centromere↗

Hereditary TP53 codon 292 and somatic P16INK4A codon 94 mutations in a Li-Fraumeni syndrome family.

Li-Fraumeni syndrome is an autosomal dominant disorder that is characterized by various types of cancer in childhood and adult cases. Although hereditary TP53 mutation is very rare in different human cancers, it has been frequently reported in Li-Fraumeni syndrome. On the other hand, hereditary mutations of TP57KIP2, P15INK4B, and P16INK4A, which affect the cell cycle similar to TP53, were observed in some types of cancer. In a Turkish family with the diagnosis of Li-Fraumeni syndrome, we analyzed the mutation pattern of TP53, P57KIP2, P15INK4B, and P16INK4A in the peripheral blood, and loss of heterozygosity (homo/hemizygous deletion) pattern of TP53 and P15INK4B/P16INK4A in two tumor tissues. The propositus had a seminoma, his daughter a medulloblastoma, and one of his healthy cousins, a TP53 codon 292 missense point mutation (AAA-->ATA; Lys-->Ile) in the peripheral blood cells. Tumor tissue obtained from the propositus with the seminoma revealed loss of heterozygosity in the TP53 gene. In the analyses of tumor tissues from the propositus and his daughter, a P16INK4A codon 94 missense point mutation (GCG-->GAG; Ala-->Glu) was observed with the hereditary TP53 mutation. P16INK4A codon 94 mutation observed in our family is a novel mutation in Li-Fraumeni syndrome. No other gene alteration in TP53, P57KIP2, P15INK4B, and P16INK4A was observed. Existence of the P16INK4A mutation and the hereditary TP53 mutation with or without loss of heterozygosity in the TP53 gene (seminoma/medulloblastoma) may be evidence for a common mechanism involved in tumorogenesis. The gene alterations in TP53 and P16INK4A genes may be used as tumor markers in our family.

Adult↗

Application of the 'Apt test' in prenatal diagnosis to evaluate the fetal origin of blood obtained by cordocentesis: results of 30 pregnancies.

This study aimed to set up a practical lab-side approach to discriminate fetal from maternal blood in samples obtained by cordocentesis. To determine the fetal origin of the blood, a modified Apt test was applied to 30 cases of prenatal diagnosis. A change of colour of the fetal and adult blood during the procedure was the hallmark to assess fetal origin. At the end of 60 s of the test, fetal blood yielded a pink colour whereas adult blood was dark green-brown. The test was repeated in mixtures of fetal and adult blood. The results suggest that the modified Apt test is a practical, quick, inexpensive, and efficient test to determine the origin of blood samples obtained by cordocentesis. However, it should be kept in mind that samples containing a mixture of both fetal and adult blood could also yield a fetal blood reaction. When maternal contamination is suspected, we propose that at least 30 metaphases from different slides should be counted. This could yield fetal as well as maternal chromosomes.

Cordocentesis↗

Hypomelanosis of ito and a 'mirror image' whole chromosome duplication resulting in trisomy 14 mosaicism.

We describe a female infant with multiple congenital anomalies including unusual hyperpigmentation, tetralogy of Fallot, absent corpus callosum and wide prominent nasal bridge. The infant was initially seen for genetic consultation on day one after birth. Chromosome analysis from cultured lymphocytes showed a normal 46,XX karyotype. However, cultured skin fibroblasts showed mosaicism with 46,XX,add(14)(q32).ish psu dic dup(14)(q32p13)(wcp14+)/46,XX complements. A review of the published report with chromosome mosaicism and hypomelanosis of Ito (HMI) is included. We suggest that the trisomy 14 mosaicism seen in fibroblast cultures has importance in the expression of pigmentation dysplasias in this patient. Pigmentary anomaly may be due to loss or gain of specific genes that influence pigmentation located on the long arm of chromosome 14 in this patient.

Abnormalities, Multiple↗

A case of Klinefelter's syndrome associated with unilateral renal aplasia.

We describe a 22-year-old patient with Klinefelter's syndrome associated with unilateral renal aplasia. Unilateral absence of kidney was detected in our ongoing screening for renal abnormalities by renal ultrasound in male hypogonadism. The present abnormality may be a co-existing entity or previously unrecognized abnormality associated with Klinefelter's syndrome since there is not reported systematic screening for urinary tract abnormalities in patients with Klinefelter's syndrome in the literature.

Adult↗