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    Assessment of 210Po and 210Pb in lichen, moss and soil around Can coal-fired power plant, Turkey
    (Springer, 2016) Belivermis, Murat; Kilic, Onder; Cayir, Akin; Coskun, Mahmut; Coskun, Munevver
    This paper deals with determination of Po-210 and Pb-210 activity concentrations using epigeic moss (Hypnum cupressiforme), bushy soil (fruticose) lichen (Cladonia rangiformis) and surface soil samples in the area around C, an coal-fired power plant, northwest Turkey. Mean activity concentrations of Po-210 and Pb-210 were found to be 303.9 and 425.8 Bq kg(-1) for moss, 161.6 and 259.1 Bq kg(-1) for lichen, and 79.9 and 91.5 Bq kg(1) for soil samples at dry weight, respectively. We propose that distance and altitude of sampling site may be of significant parameters of distribution of both radionuclides.
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    Assessment of the genotoxic potential of a migraine-specific drug by comet and cytokinesis-block micronucleus assays
    (Taylor & Francis Ltd, 2020) Cayir, Akin; Cobanoglu, Hayal; Coskun, Munevver
    Background: Eletriptan is a migraine-specific drug-containing the triptan group. In terms of drug safety, the present study aimed to investigate the genotoxic potential of eletriptan. Research design & methods: We conducted our study by using the cytokinesis-block micronucleus cytome (CBMN) assay, a comprehensive method for measuring micronucleus formation, and a sensitive method for detecting DNA-strand breaks. In the assay, cytokinesis-block proliferation index and the frequency of micronuclei were evaluated in lymphocytes treated with three different concentrations (1, 10 and 25 mu g/ml) of eletriptan for 48 hours. In comet assays, DNA damage was evaluated in leucocytes treated with three different concentrations (1, 10 and 25 mu g/ml) of eletriptan for an hour. Results: Eletriptan did not induce cytotoxicity nor any increased micronuclei frequencies. While the comet parameters % DNA in tail, tail moment, and the olive moment was found to be significantly increased at 10 and 25 mu g/ml, the cytokinesis-block proliferation index values were not. Conclusion: These findings suggest that eletriptan is non-cytotoxic but potentially weakly genotoxic at higher concentrations (10 and 25 mu g/ml).
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    Associations of Annual Ambient Fine Particulate Matter Mass and Components with Mitochondrial DNA Abundance
    (Lippincott Williams & Wilkins, 2017) Peng, Cheng; Cayir, Akin; Sanchez-Guerra, Marco; Di, Qian; Wilson, Ander; Zhong, Jia; Kosheleva, Anna
    Background: Fine particulate matter (PM2.5) represents a mixture of components with potentially different toxicities. However, little is known about the relative effects of PM2.5 mass and PM2.5 components on mitochondrial DNA (mtDNA) abundance, which may lie on the pathway of PM2.5-associated disease. Methods: We studied 646 elderly male participants in the Normative Aging Study from Greater Boston to investigate associations of long-term exposure to PM2.5 mass and PM2.5 components with mtDNA abundance. We estimated concentrations of pollutants for the 365-day preceding examination at each participant's address using spatial- and temporal-resolved chemical transport models. We measured blood mtDNA abundance using RT-PCR. We applied a shrinkage and selection method (adaptive LASSO) to identify components most predictive of mtDNA abundance, and fit multipollutant linear mixed-effects models with subject-specific intercept to estimate the relative effects of individual PM component. Results: MtDNA abundance was negatively associated with PM2.5 mass in the previous year and-after adjusting for PM2.5 mass-several PM2.5 components, including organic carbon, sulfate (marginally), and nitrate. In multipollutant models including as independent variables PM2.5 mass and PM2.5 components selected by LASSO, nitrate was associated with mtDNA abundance. An SD increase in annual PM2.5-associated nitrate was associated with a 0.12 SD (95% confidence intervals [CI] = -0.18, -0.07) decrease in mtDNA abundance. Analyses restricted to PM2.5 annual concentration below the current 1-year U.S. Environmental Protection Agency standard produced similar results. Conclusions: Long-term exposures to PM2.5-associated nitrate were related to decreased mtDNA abundance independent of PM2.5 mass. Mass alone may not fully capture the potential of PM2.5 to oxidize the mitochondrial genome. See video abstract at, http://links.lww.com/EDE/B274.
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    Cell-free dna methylation evaluation in patients with thyroid diseases
    (Bayrakol Medical Publisher, 2022) Cilgin, Guner Begum; Cil, Ozge Caglar; Uslu, Atilla; Cayir, Akin
    Aim: The main aim of the study was to evaluate the DNA 5-methylcytosine (m5C) level, measured in circulating cell-free DNA (ccfDNA) as a distinct feature of thyroid gland-related disorders, including thyroiditis, benign nodule, and malignant nodule.Material and Methods: The study included 75 patients with 30 benign nodules, 30 thyroiditis, and 15 thyroid cancers; 19 subjects were evaluated as a control group. We collected peripheral blood samples from three disease groups and the controls, and then separated the plasma from the whole blood. We measured m5C in ccfDNA purified from plasma samples of patients and healthy individuals.Results: The level of m5C, measured in thyroiditis patients was significantly different from those measured in the control group, malignant and benign patients. We observed hypomethylation in benign and malignant patients when compared with the control group. However, there was no significant difference between the malignant patients and the control group and between the benign patients and the control group. After comparison of disease groups, we observed that there was no statistically significant difference between benign and malignant patients. We observed a statistically significant difference between thyroiditis and malignant patients (p<0.01) and between thyroiditis and benign patients (p=0.001).Discussion: Very few studies have reported that DNA methylation is an epigenetic mechanism in thyroiditis patients. Here, we reported that the level of m5C of ccfDNA could be used as a biomarker for thyroiditis. Further studies are required with the higher number of malign and benign patients to investigate the differences between patients with nodules and healthy individuals.
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    Comet assay for assessment of DNA damage in greenhouse workers exposed to pesticides
    (Taylor & Francis Ltd, 2019) Cayir, Akin; Coskun, Mahmut; Coskun, Munevver; Cobanoglu, Hayal
    Purpose: The main goal of the present study was to determine DNA damage in pesticide-exposed greenhouse workers and pesticides non-exposed controls. Materials and methods: The DNA damage was measured by alkaline comet assay method (pH > 13) in 41 greenhouse workers and 45 non-exposed individuals as the control. Pesticide exposure was assessed by duration of working in the greenhouse and pesticide application in the greenhouse time. DNA damage was estimated by arbitrary unit and damage frequency. Results: Arbitrary unit and damage frequency were consistently significantly higher in greenhouse workers than those of the controls (p = 0.001). In terms of gender in greenhouse, DNA damage of female workers was significantly higher than those in male workers (p < 0.05). We found significant correlation between DNA damage and working hours spent. Multiple linear regression analysis showed that working hours in the greenhouse as an indication of pesticide exposure were significantly associated with the DNA damage, which can be attributed to the genotoxic potential of the pesticide mixture. Conclusions: The comet assay is sensitive to detect the damage exposed to chronic effect of pesticides in greenhouse workers. Significant DNA damage was obtained for the exposed group, which was associated with the pesticide exposure.
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    Comparison of buccal micronucleus cytome assay parameters in the pesticide-exposed greenhouse workers with the controls
    (Elsevier Ireland Ltd, 2017) Cayir, Akin; Coskun, Munevver; Cobanoglu, Hayal; Coskun, Mahmut
    [Anstract Not Available]
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    Comparison of Epigeic Moss (Hypnum cupressiforme) and Lichen (Cladonia rangiformis) as Biomonitor Species of Atmospheric Metal Deposition
    (Springer, 2009) Coskun, Mahmut; Steinnes, Eiliv; Coskun, Munevver; Cayir, Akin
    In the present work epigeic moss (Hypnum cupressiforme Hedw.) and epigeic lichen (Cladonia rangiformis Hoffm.) samples were collected simultaneously in the Thrace region, Turkey according to a regular sampling grid. Whereas the moss was found at all 68 sampling sites, the lichen could be collected only at 25 of the sites, presumably because lichens are more sensitive than mosses with respect to air pollution and climatic variations. All elements showed higher accumulation in the moss than in the lichen whereas element inter-correlations were generally higher in the lichen. All considered the moss was judged to be a better choice than the lichen for biomonitoring of atmospheric deposition of metals in this case, and it is argued that mosses may be generally more suited than lichens for this purpose.
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    Concentrations of some elements in the Bioindicator Organism Cladonia rangiformis Collected at the Vicinity of Canakkale
    (Foundation Environmental Protection & Research-Fepr, 2008) Cayir, Akin; Coskun, Muenevver; Coskun, Mahmut
    Lichen samples (Cladonia rangiformis) were collected at 10 different sampling sites to determine distribution patterns and concentrations of Al, Ba, Ca, Co, Fe, X, Li, Mg, Mn, Na, Ni, and Ti in lichen at the vicinity of Canakkale. Microwave digestion system was used for mineralization of lichen samples. The concentrations of elements were determined using ICP-OES and the map of spatial distribution of each element's was plotted. Results showed that the distribution patterns of Al, Fe, Ti, Co, and Li were similar in the study area. The highest concentrations of these five elements were determined in Balikesir-Balya region. The distribution of Na, Mg, Ca, and Sr were also similar, and the maximum concentrations of these elements were determined near the sea shore sampling stations.
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    Correction: Mitochondria and aging in older individuals: An analysis of DNA methylation age metrics, leukocyte telomere length, and mitochondrial DNA copy number in the VA normative aging study [Aging., 12, (2019) (2070-2083)] DOI: 10.18632/aging.102722
    (Impact Journals LLC, 2020) Dolcini, Jacopo; Wu, Haotian; Nwanaji-Enwerem, Jamaji C.; Kiomourtozlogu, Marianthi-Anna; Cayir, Akin; Sanchez-Guerra, Marco; Vokonas, Pantel
    The authors requested to correct the last name of Marianthi-Anna Kioumourtzoglou which was misspelled. This mistake does not change the content of publication. © 2020 Dolcini et al.
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    Cross-Border Response of Moss, Hypnum cupressiforme Hedw., to Atmospheric Deposition in Southern Bulgaria and Northeastern Greece
    (Springer, 2009) Yurukova, Lilyana; Tsakiri, Evdoxia; Cayir, Akin
    This study aimed at first cross-border mapping of 10 heavy metals and toxic elements accumulation in moss Hypnum cupressiforme reflecting wet and dry atmospheric deposition in Southern Bulgaria and Northeastern Greece. It is a part of the European moss survey 2005/2006 including first Greek results. Data obtained from 66 sites, covering 20,000 km(2), showed different deposition patterns particularly for As, Cd, Cr and Pb. The determined concentrations (ICP-AES), revealed no serious pollution by airborne heavy metals and toxic elements contaminants. Lead was the only element with proved statistical significant difference, between Bulgarian and Greek part of the study area.
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    Determination of atmospheric heavy metal pollution in Canakkale and Balikesir provinces using lichen (Cladonia rangiformis) as a bioindicator
    (Springer, 2007) Cayir, Akin; Coskun, Munevver; Coskun, Mahmut
    A regional study was conducted to assess the current level of atmospheric heavy metal pollution (Pb, Zn, Cr, Cu, Cd) in the Canakkale and Balikesir provinces of Turkey, and also to establish a baseline for future studies of atmospheric heavy metal pollution. The lichen Cladonia rangiformis was used for determining the distribution of heavy metals in the atmosphere. The highest concentration of all these elements was observed in the vicinity of Balikesir province where there is an abandoned lead-zinc main. On the other hand, apart from the mining area, the concentration of heavy metals was similar to the data reported for unpolluted areas. Maximum values of Pb, Zn, Cr, Cu, and Cd were 33.8, 47.6, 13.0, 5.29, and 0.69 mg/kg in dry weight, respectively. Spatial distribution of these elements, apart from Cr, was similar. Correlation coefficients between Zn-Pb, Cr-Zn, Cu-Pb, Cu-Zn, Cd-Zn, and Cd-Cr were high and positive, and indicated that they come from the same sources.
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    Different working conditions shift the genetic damage levels of pesticide-exposed agriculture workers
    (Springer Heidelberg, 2020) Cobanoglu, Hayal; Coskun, Munevver; Coskun, Mahmut; Cayir, Akin
    In the current study, we had two main purposes. Firstly, we aimed to compare genetic damages in the agricultural workers of two different types of environmental conditions including the greenhouse and open fields. Secondly, we aimed to compare genetic damages in the total agricultural workers as the exposed group (greenhouse and open field workers) (n = 114) and the non-exposed control group (n = 98) living in the same area in Canakkale, Turkey. For these purposes, we investigated the incidence of micronucleus (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) in peripheral blood lymphocytes. We observed that the frequencies of MN, NPB, and NBUD obtained for the greenhouse workers were statistically significantly higher than those obtained for the open field workers. When the results of the control group were compared with those of the total workers, there were statistically significant differences in terms of MN and NBUD frequencies. We found that age and MN were correlated at a significant level in both the agricultural workers and the control group. The MN frequency of the female workers was 1.5 times greater than that of the male workers, and it was a significant level in the agricultural workers.
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    DNA damage and circulating cell free DNA in greenhouse workers exposed to pesticides
    (Wiley, 2018) Cayir, Akin; Coskun, Mahmut; Coskun, Munevver; Cobanoglu, Hayal
    Pesticides widely used in agriculture and other applications have been linked to cancer and other diseases through several potential mechanisms. The goals of this study were to assess DNA damage in lymphocytes by the cytokinesis-block micronucleus assay (CBMN), and to measure circulating cell free DNA (ccf-DNA) in the blood of pesticide-exposed greenhouse workers and matched controls living in the same area. CBMN was applied to peripheral blood lymphocyte samples taken at different times (spring and autumn) for each individual. We measured plasma ccf-DNA levels using a Qubit((R)) fluorometer. The results indicated that the MNL, BNMN, and NBUDs frequencies of pesticide-exposed individuals were significantly higher than non-exposed individuals. Apart from MNL, BNMN and CBPI, a season-related effect was found for the NPB and NBUD frequencies. With MNL and BNMN as the dependent variables, multiple regression analysis showed that age and gender affected MN formation. The ccf-DNA level in the pesticide-exposed group was significantly higher than the control group. There was no seasonal variation regarding the free DNA amount. Ccf-DNA in males was found to be higher than females. The MNL, BNMN, NPB, and CBPI did not correlate with the ccf-DNA amount. It can be concluded that pesticide exposure can modulate DNA integrity via different mechanisms. Also, elevated levels of ccf-DNA could be recommended as a biomarker of pesticide exposure. Environ. Mol. Mutagen. 59:161-169, 2018. (c) 2017 Wiley Periodicals, Inc.
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    Environmental epitranscriptomics
    (Academic Press Inc Elsevier Science, 2020) Cayir, Akin; Byun, Hyang-Min; Barrow, Timothy M.
    Chemical modifications of RNA molecules have gained increasing attention since evidence emerged for their substantive roles in a range of biological processes, such as the stability and translation of mRNA transcripts. More than 150 modifications have been identified in different organisms to date, collectively known as the 'epitranscriptome', with 6-methyladenosine (m(6)A), 5-methylcytidine (m(5)C), pseudouridine and N1-methyladenosine (m(1)A) the most extensively investigated. Although we are just beginning to elucidate the roles of these modifications in cellular functions, there is already evidence for their dysregulation in diseases such as cancer and neumdevelopmental disorders. There is currently more limited knowledge regarding how environmental exposures affect the epitranscriptome and how this may mediate disease risk, but evidence is beginning to emerge. Here, we review the current evidence for the impact of environmental exposures such as benzo[a]pyrene, bisphenol A, pesticides, metals and nanoparticles upon RNA modifications and the expression of their 'writers' (methyl transferases), 'erasers' (demethylases) and `readers'. We discuss future directions of the field and identify areas of particular promise and consider the technical challenges that are faced.
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    Environmental exposures and RNA N6-Methyladenosine modified long Non-Coding RNAs
    (Taylor & Francis Ltd, 2020) Cayir, Akin
    Recent advances in the field of RNA modifications and long non-coding RNAs (lncRNAs) have provided substantial evidence on important biological functions. LncRNAs are defined as longer than 200 nucleotides which are not translated into proteins. The term epitranscriptome refers to all modifications in RNA types. Adenine-6 methylation (m(6)A) is the most common, dynamic and prominent modifications in coding and non-coding RNAs and has critical and previously unappreciated functional roles. Accumulation evidence indicated the association between RNA m6A modification and cancer and nonmalignant diseases. Recent studies reported that several lncRNAs includingMALAT1, MEG3, XIST, GAS5,andKCNK15-AS1are subject to m(6)A modification. It can be suggested that lncRNAs modified by m(6)A modification have substantive roles in diseases. Currently limited data are available regarding how environmental exposure affects m(6)A-modified lncRNAs. Furthermore, we do not know the interaction of environmental exposure and m(6)A-modified lncRNAs in development of adverse human health outcomes. Thus, in this systematic review, we aimed to present the data of the studies that reported a significant association between environmental exposure and expression/DNA methylation of m(6)A-modified long non-coding RNAs.
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    Evaluation of background DNA damage in a Turkish population measured by means of the cytokinesis-block micronucleus cytome assay
    (Elsevier, 2013) Coskun, Mahmut; Cayir, Akin; Coskun, Munevver; Tok, Hayal
    This study aimed to determine the background incidence of micronuclei (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) in the peripheral blood lymphocytes of a population in the province of Canakkale, Turkey. Seventy-one individuals living under similar socio-economic conditions, not exposed to an X-ray examination during the last six months, receiving no medical treatment and not involved in agricultural activities were evaluated. In addition to genetic end-points, the cytokinesis-block proliferation index (CBPI) was determined. MN and NBUD frequencies gradually increased with age. MN frequencies of the older group were similar to 7 fold higher than those of the younger group. Multiple linear regression analysis showed that apart from age, no significant effects of various confounding factors on MN and NBUD were observed. NPB frequencies were affected by gender. In the present study, no statistically significant effect was found of smoking on the genetic end-points evaluated, which agrees with results from other studies. (C) 2013 Elsevier B.V. All rights reserved.
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    Evaluation of circulating cell free DNA as biomarker of pesticide exposure
    (Elsevier Ireland Ltd, 2017) Cayir, Akin; Coskun, Mahmut
    [Anstract Not Available]
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    Evaluation of circulating cell free DNA in plasma as a biomarker of different thyroid diseases
    (Assoc Brasileira Otorrinolaringologia & Cirurgia Cervicofacial, 2020) Caglar, Ozge; Cilgin, Begum; Eroglu, Mustafa; Cayir, Akin
    Introduction: Many studies have been done on proteomics, genomics, epigenetic, immuno-genetics in many body fluids. Among these, circulating cell-free DNA (ccfDNA) entered the literature in 1948, but it has not been studied for many years due to technological deficiencies. Following recent advances, geno-metastasis has been mentioned and new research is needed in this area. ccfDNA is known to be an important biomolecule in this regard. Objective: The presence of cell-free DNA in the circulatory system may offer a tremendous opportunity to provide novel biomarkers for thyroid diseases. This experimental study was conducted to determine the amount of ccfDNA in different thyroid diseases, then to evaluate whether the ccfDNA concentration varied between the disease groups and control group. Methods: In total, we included 121 individuals in the present study. We collected blood samples and then determined the ccfDNA concentration in plasma of collected blood samples from three groups: thyroiditis (n=33), benign (n =37), and malignant (n =30) and from a control group (n=21). Results: The median values of the ccfDNA groups were found as 1610, 1665, 1685 and 576 ng/mL for the thyroiditis, benign, malign, and control groups, respectively. Findings showed that the ccfDNA of the three groups was significantly higher than the control (p <0.0001). Each group was compared in terms of ccfDNA and the p-values of benign-thyroiditis, benign-malign, and thyroiditis-malign were 0.09, 0.65, and 0.29, respectively. Conclusions: The clear differences between thyroid diseases and controls suggest that ccfDNA is worthy of attention as a biomarker for further evaluation of different thyroid diseases. Likewise, it might indicate a clear tendency that ccfDNA can also be used to distinguish different thyroid diseases. (C) 2019 Associacao Brasileira de Otorrinolaringologia e Cirurgia Cervico-Facial. Published by Elsevier Editora Ltda.
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    Evaluation of circulating cell-free nucleic acids in health workers occupationally exposed to ionizing radiation
    (Springer Heidelberg, 2022) Kilinc, Nihal; Onbasilar, Mehmet; Cayir, Akin
    Radiology workers might constantly be exposed to low-dose ionizing radiation due to their profession. Low doses of radiation in a short exposure time have the potential to alter the genome, which might potentially lead to diseases. The main objective of this study was to determine whether the amount of cell-free nucleic acids in plasma samples of radiation-exposed workers was different from the general public, in other words, non-exposed individuals. In this context, we investigated the association between radiation exposure and cell-free nucleic acids concentration by using radiation exposure parameters. The study consisted of 40 radiology workers and 40 individuals who were not exposed to ionizing radiation. The plasma concentrations of cell-free DNA, RNA, and miRNA were measured fluorometrically. We found that the ccfRNA concentration of the radiation-exposed group was significantly different from that of the non-exposed group (p = 0.0001). However, there are no differences between both groups in terms of ccfDNA and ccfmiRNA concentration. The concentration of ccfDNA is significantly correlated with working time in the fluoroscopy field (p < 0.05). We found that the concentration of ccfmiRNA was significantly correlated with working time in plain radiography (p < 0.01) and computed tomography (p < 0.05) and with total working time (p < 0.01). Similarly, the concentrations of ccfRNA were significantly correlated with working time in computed tomography (p < 0.01) and with the total working time (p < 0.05) of the workers. We found that imaging number in computed tomography significantly altered the level of ccfRNA (p = 0.006) and that working time in the computed tomography field significantly affected the ccfRNA concentration (p = 0.03, R-2 =0.36 for model). Finally, we determined that total working time was significantly associated with total ccfRNA concentration (p < 0.05, R-2 =0.25 for model). In conclusion, total RNA measured in radiation-exposed workers has the potential to predict the radiation exposure risk. Furthermore, total working time and working time in the tomography field significantly alter the level of free nucleic acids.
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    Evaluation of genotoxic potential of pemetrexed by using in vitro alkaline comet assay
    (Marmara Univ, Fac Pharmacy, 2017) Cobanoglu, Hayal; Coskun, Munevver; Coskun, Mahmut; Cayir, Akin
    Pemetrexed is a chemotherapeutic drug, approved for the treatment of mesothelioma and non-small cell lung cancer and variety of neoplasm. Chemotherapeutic drugs don't target only cancer cells in treatment. During treatment these drugs encounter with normal cells as well. Therefore, in this in vitro study, it was aimed to investigate the whether genotoxic effect or not of Pemetrexed on normal leukocytes. In vitro alkaline comet assay was used in this study. Leukocytes from human peripheral blood samples from two volunteer donors were used in the study. In the present study, leukocytes were treated with four different concentrations (25, 50, 75, and 100 mu g/ml) of the drug for 1 hour. At concentration of 75 mu g/ml and 100 mu g/ml, there were statistically significant increases in DNA damage compared to the negative control (p<0.05, and p<0.01 respectively). The obtained result shows that Pemetrexed may have genotoxic potential on normal leucocytes.