Sitki Oztas

Increased salivary level of 8-hydroxydeoxyguanosine is a marker of premature oxidative mitochondrial DNA damage in gingival tissue of patients with periodontitis

Introduction:Oxidative stress may contribute to the pathogenesis of periodontitis. However, the detailed molecular mechanism remains unclear. Both 8-hydroxydeoxyguanosine (8-OHdG) and mitochondrial DNA (mtDNA) deletion have been reported as early oxidative DNA damage markers. In this study, 8-OHdG levels in saliva and mtDNA deletions in gingival tissue of patients with chronic periodontitis (CP) were evaluated.Materials and Methods:Gingival tissue and whole saliva samples were collected from 32 patients with CP and 32 healthy control subjects. To determine the clinical condition of each subject, the plaque index, gingival index, clinical attachment level (CAL), and probing depth (PD) were measured. Using the ELISA and polymerase chain reaction methods, the salivary 8-OHdG levels and the 7.4-kbp and 5-kbp mtDNA deletions were examined.Results:The 5-kbp mtDNA deletion was detected in 20 of the 32 periodontitis patients (62.5%), but was not detected in the healthy controls. The mean value of 8-OHdG in the saliva of the periodontitis patients with deleted mtDNA was significantly higher than in the patients with non-deleted mtDNA (p<0.01). Also, significant correlation was found between the occurrence of the 5-kbp mtDNA deletion and salivary 8-OHdG levels (p<0.01). Similar correlations were detected between salivary 8-OHdG levels and age, PD, and CAL (p<0.01, p<0.05).Conclusion:Increased oxidative stress may lead to premature oxidative DNA damage in the gingival tissue of periodontitis patients and the salivary 8-OHdG level may signify premature oxidative mtDNA damage in diseased gingival tissue.

Evaluation of the genotoxic effects of chronic low-dose ionizing radiation exposure on nuclear medicine workers

INTRODUCTION Nuclear medicine workers are occupationally exposed to chronic ionizing radiation. It is known that ionizing radiation may have damaging effects on chromosomes. In the present study, we investigated the genotoxic effects of ionizing radiation on nuclear medicine workers. We used two different indicators of genotoxicity methods: sister chromatid exchange (SCE) and micronucleus (MN). METHODS The present research was carried out using 21 nuclear medicine workers (11 females and 10 males) during two periods: during normal working conditions and after a 1-month vacation. The radiation dose varied from 1.20 to 48.56 mSv, which accumulated during the occupational exposure time between two vacations. Peripheral blood samples were taken from each subject for two distinct lymphocyte cultures (SCE and MN) in each period. RESULTS In nearly all subjects, SCE values increased significantly during radiation exposure compared to the postvacation period (P<.05). Similarly, MN frequencies in most of the subjects increased significantly during radiation exposure compared to the postvacation period (P<.05). CONCLUSIONS This study revealed that both SCE and MN frequencies in most of the subjects were significantly higher during exposure to ionizing radiation than after a 1-month vacation period. However, this genotoxic effect was reversible in most of the subjects.

Sister chromatid exchange analysis in patients exposed to low dose of iodine-131 for thyroid scintigraphy

To determine the genotoxic risk associated with diagnostic exposure to low doses of iodine 131 (131I), sister chromatid exchange (SCE) analysis was performed in lymphocytes of 18 non-smoking women who received 370 kBq (10 microCi) intravenous 131I sodium iodide as an adjuvant for scintigraphy for diagnosing thyroid nodularity. SCE frequencies were measured before and after 131I administration. SCE results in the pre-treated phase were regarded as control. Although SCE values 24 h after 131I administration did not show a significant increment (p > 0.05), there was a significant increase 72 h after treatment (p < 0.05). These results indicate that genetic damage might be induced by low dose of 131I.

Primary hypogonadism, partial alopecia, and Mullerian hypoplasia: Report of a third family and review†

Two sisters presented with partial alopecia, primary hypergonadotropic hypogonadism and Mullerian hypoplasia associated with mild mental retardation, microcephaly, flat occiput, sparse eyebrows, absence of breast tissue, absent ovaries, mild‐moderate dorsal kyphosis, thin upper lip and unilateral sensorioneural deafness in one of them. They were the product of a Turkish consanguineous marriage. The clinical course for our patients is similar to two families reported by Al‐Awadi et al. [Al‐Awadi et al. (1985) Am J Med Genet 22:619–622] and Megarbane et al. [Megarbane et al. (2003) Am J Med Genet Part A 119A:214–217]. This report supports the literature by proposing an autosomal recessive syndrome which was firstly reported by Al‐Awadi et al. [Al‐Awadi et al. (1985) Am J Med Genet 22:619–622]. This condition may be due to a founder mutation.

Chromosome and sister chromatid exchange studies in Behcet's patients.

Behcets disease is a chronic multisystemic disease of unknown pathogenesis characterized by four major symptoms: oral aphthous ulcers, skin lesions, ocular symptoms and genital ulcerations. The disease is spread throughout the world, but it is most frequent in Turkey, Japan, Korea and China. Although HLA‐Bw51 has been found to predominate in Behcets cases, the genetic etiology has not yet been clarified. In this study, we investigated the chromosomal abnormalities and sister chromatid exchange rates in patients with Behcets diseases. Thirty‐eight patients with Behcets disease (diagnosed for the first time) and 30 healthy subjects (as controls) were included in this study. Although numerical and structural chromosomal abnormalities were not detected in our patients, we found an increased rate of sister chromatid exchange in patients over the control groups (P < 0.01). On the basis of these results, we discuss the genetic etiology of Behcets disease.

Chromosome abnormalities in protein-energy malnutrition

Abstract The present study attemps to investigate the impact of protein-energy malnutrition (PEM) on chromosomal abnormalities in children. Sixty-seven children suffering from marasmus, marasmic-kwashiorkor, and kwashiorkor were chosen from the inpatient Pediatric Department of Medical Faculty of Ataturk University. They were matched by age, sex, and socioeconomic status to twenty-five health children (control). After 72 hours, 100 cultured lymphocyte cells from each subject were analyzed. The frequency of chromosome abnormalities was found to be nearly nine time greater among children with PEM compared to controls (12.59% versus 1.24% respectively); the difference was statistically highly significant, p

Mitochondrial DNA 4977 bp Deletion in Chronic Cervicitis and Cervix Cancers

Mitochondrial DNA 4977 bp Deletion in Chronic Cervicitis and Cervix Cancers Mitochondrial DNA (mtDNA) mutations have been implied in many diseases including cancer and inflammatory diseases. The aim of this study is to investigate the relationship between the 4977 bp deletion of the mtDNA and chronic cervicitis or cervix cancer in patients. The study included a group of patients with chronic cervicitis or cervix cancer, and a control group consisting of individuals without any cervical tissue disease. A total of 72 subjects in an East Turkish population were included in the study. Of these, 35 had chronic cervicitis, 21 had cervix cancer and 16 served as the control group. Isolation of mtDNA was performed from the tissues of these patients and then mtDNA deletions were studied using polymerase chain reaction (PCR). In the cancer groups, there were 9.5% heteroplasmic and homoplasmic deletions. There were no homoplasmic deletions in the cervicitis and control groups, but the frequencies of heteroplasmic deletions were 80.0 and 31.2%, respectively. Chronic inflammation leading to increased reactive oxygen species (ROS) may be the cause of the high mtDNA 4977 bp deletion frequencies in cancer and cervicitis. The older age of the cancer patient may suggest that ageing in addition to long time exposure to ROS may lead to deletions and subsequently cancer. This is the first study to investigate the relationship of the mtDNA 4977 bp deletion to chronic cervicitis and cervix cancer.

Molecular diagnosis of autosomal recessive non-syndromic hearing losses

Amac: Bu calismada, Erzurum ili ve cevresinde isitme bozuk- luklarinin genetik yonden arastirilmasi, non-sendromik oto- zomal resesif isitme kaybina neden olan GJB2 gen mutasyon- larinin belirlenmesi ve mutasyon profilinin cikartilmasi amac- lanmistir. Yontem: Bu calismaya 50 isitme kayipli hasta ve 50 saglikli gonullu alinmistir. KBB servisinde muayene ve isitme testleri yapilan hastalar, sendromik acidan bolumumuzde degerlen- dirilmistir. DNA ekstraksiyonunu takiben GJB2 geni Polime- raz zincir reaksiyonu (PCR) ile amplifiye edilmis ve PCR-SSCP ve RFLP teknikleri kullanilarak; 35delG, 235delC, 167delT, 176-191del16, V95M ve W77X mutasyonlarinin varligi arasti- rilmistir. Bulgular: Calisma grubumuzu olusturan 50 hastanin GJB2 gen incelemesinde 10 hastada (7 homozigot ve 3 heterozi- got) 35delG mutasyonu tespit edilmistir. Bu 7 homozigot hastanin ulasabildigimiz iki tanesinin ebeveyninde heterozi- got 35delG mutasyonu saptanmistir. Calisilan 50 saglikli kontrolun bir tanesinde heterozigot 35delG mutasyonu saptanmis olup, genetik danismanlik verilmistir. GJB2 genine ait diger mutasyonlar (V95M, 176-191Del16, 235DelC, 167DelT, W77X) calisilan her iki grupta da tespit edilememis- tir. Sonuc: Calismamizin sonucunda Erzurum bolgesinde GJB2 gen mutasyonlarinin non-sendromik otozomal resesif isitme kaybi olan bireylerde hastaligin etiyolojisinde onemli bir neden oldugu saptanmistir. Background: : The aim of this study was to investigate the auditory disorders in or around Erzurum from the genetic aspects, to determine GJB2 gene mutations that lead to non- syndromic autosomal recessive hearing loss and to deter- mine mutation profile for this gene. Method: 50 patients with hearing loss and 50 healthy volun- teers participated to this study. Patients whose examination and auditory tests were performed at the ear-nose-throat outpatient clinics were referred to us to be evaluated for an underlying syndrome. GJB2 gene was amplified with poly- merase chain reaction (PCR) after DNA extraction and pres- ence of 35delG, 235delC, 167delT, 176-191del16, V95M and W77X mutations were investigated by using PCR-SSCP and RFLP techniques. Results: As a result of the GJB2 gene studies of the 50 pa- tients in the study group, 35delG mutation was detected in 10 patients (7 homozygous and 3 heterozygous). Of these 7 patients with homozygous mutations, we could reach the parents of 2 patients and heterozygous 35de1G mutation was detected in these. Among the 50 healthy control sub- jects, a heterozygous 35de1G mutation was detected in 1 patient and this patient was given genetic counseling. The other mutations that belong to GJB2 gene (V95M, 176- 191Del16, 235DelC, 167DelT, W77X) were not detected in either of the groups. Conclusion: As a result of our study, GJB2 gene mutations were detected to be an important etiological factor in pa- tients with autosomal recessive hearing disorders residing in or around Erzurum. Anahtar Kelimeler: GJB2, Non-sendromik isitme kaybi, SSCP. Keywords: GJB2, Non-sendromic hearing loss, SSCP.