Taylan Onat

Dr. Taylan Onat

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 November 2020 in Biological Trace Element Research
Verified
Journal Article
Closed access
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TOTaylan Onat
Taylan Onat
MCMelike Demir Caltekin
Melike Demir Caltekin
VTVugar Ali Turksoy
Vugar Ali Turksoy
EBEmre Baser
Emre Baser
DKDemet Aydogan Kirmizi
Demet Aydogan Kirmizi
EYEthem Serdar Yalvac
Ethem Serdar Yalvac

23 February 2020 in The Journal of Maternal-Fetal & Neonatal Medicine
Verified
Journal Article
Closed access
EBEmre Baser
Emre Baser
DKDemet Aydogan Kirmizi
Demet Aydogan Kirmizi
DIDilek Ulubas Isik
Dilek Ulubas Isik
SOSafak Ozdemirci
Safak Ozdemirci
TOTaylan Onat
Taylan Onat
OTOzlem Moraloglu Tekin
Ozlem Moraloglu Tekin
Objective: Preterm premature rupture of membranes (PPROM), associated with prematurity, is an important obstetric complication that may cause neonatal mortality and morbidity. The optimal delivery time is controversial in cases with the expectant approach. The fetal effects of long-term exposure to PPROM are unknown. This study aimed to evaluate the maternal and fetal outcomes of expectantly-managed PPROM cases with different latency periods at 240/7–346/7 weeks of gestation. Material and method: The study group consisted of 206 patients at 240/7–346/7 weeks of gestation who met the inclusion criteria. Patients were divided into three groups according to their weeks of PPROM diagnosis as 240/7−286/7, 290/7−316/7, and 320/7−346/7. The period from membrane rupture to delivery was defined as the latency period and divided into three subgroups as 3–7 days, 8–13 days and ≥14 days. In addition to the demographic characteristics of the patients, maternal and obstetric complications, primary and secondary neonatal outcomes were compared between the groups. Primary neonatal outcomes were determined in terms of pathological Apgar scores (<5 at minute 1, <7 at minute 5), requiring resuscitation, admission to Neonatal Intensive Care Unit (NICU) and NICU length of stay. Secondary neonatal outcomes were determined in terms of respiratory distress syndrome, bronchopulmonary dysplasia, intraventricular hemorrhage, retinopathy of prematurity, necrotizing enterocolitis, patent ductus arteriosus, periventricular leukomalacia, and neonatal sepsis. In addition, for the prediction of morbidity and mortality, newborns were evaluated by SNAPPE II (Score for Neonatal Acute Physiology with Perinatal extension-II) consisting of the combination of biochemical and physiological parameters, using the parameters including mean blood pressure (mm/Hg), corporal temperature (°C), PO2/FiO2 ratio, lowest serum pH, multiple seizures, urine output (ml/kg/hr), Apgar score, birth weight, and small for gestational age. The higher the score of SNAPPE II, the higher the morbidity and mortality risk of neonates. For the statistical analysis, the Kruskal Wallis and one-way ANOVA tests were utilized for the numerical data. Categorical data were compared using the chi-square test. The receiver operating characteristic (ROC) test was used to determine the threshold value of the data affecting neonatal morbidity. Results: The mean PPROM week was found to be 29.7 ± 3.0 weeks and the mean delivery week was 31.8 ± 2.5 weeks. The mean latency period for all the patients was 15.1 ± 13.8 days. Clinic chorioamnionitis was observed in 17% of the cases. The lowest chorioamnionitis rate (8.6%) was in the 3–7-day latency period group. Total complications were significantly lower in the 290/7–316/7 week PPROM group in which the latency period was ≥14 days, compared to those in 3–7 days and 8–13 days (p = .001). Total complications were lower in the < 32 weeks PPROM groups in which the latency period was ≥14 days compared to those obtained in 3–7 days and 8–13 days. There was no significant difference between the latency period and total complications after 32 weeks (p = .422). The best discriminative cutoff value of SNAPPE-II for neonatal morbidity was 11.0 (sensitivity 82%, specificity 80%). In the present study, the optimal latency period for the best neonatal outcomes was found to be 34.5 days (sensitivity 70% and specificity 84%) between weeks 240/7–286/7, and 11.0 days between weeks 290/7–316/7 (sensitivity 68% and specificity 85%). Conclusions: Our findings indicated that a long latency period did not increase neonatal morbidity and there was no increase in neonatal complications after 32 weeks of the gestational period compared to those obtained before 32 weeks.

14 September 2020 in Sleep and Biological Rhythms
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Journal Article
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IÇİbrahim Çaltekin
İbrahim Çaltekin
MHMehmet Hamamcı
Mehmet Hamamcı
MÇMelike Demir Çaltekin
Melike Demir Çaltekin
TOTaylan Onat
Taylan Onat

29 July 2020 in Journal of Turkish Society of Obstetric and Gynecology
Verified
Journal Article
Open access
TOTaylan Onat
Taylan Onat
DKDemet Aydoğan Kırmızı
Demet Aydoğan Kırmızı
EBEmre Başer
Emre Başer
MEMüjgan Ercan
Müjgan Ercan
MÇMelike Demir Çaltekin
Melike Demir Çaltekin
EYEthem Serdar Yalvaç
Ethem Serdar Yalvaç
Preeclampsia (PE) is a dangerous complication of pregnancy and still a major cause of maternal-fetal morbidity and mortality. Its etiology remains largely unknown, but researchers have suggested oxidative stress-mediated inflammation for the same. The purpose of this study is to investigate the relationship between oxidative stress and PE as well as the usability of oxidative stress indicators such as serum ischemia-modified albumin (IMA) levels and thiol/disulfide balance in the prediction of PE. The study included 47 pregnant women with PE and 57 healthy pregnant women. We measured their serum IMA, native thiol, total thiol, and disulfide levels. Additionally, we determined the optimal cutoff values via the receiver operating characteristic curve analysis. There were no differences between the two groups with respect to the maternal age, body mass index, gravida, and parity. The native and total thiol levels were found to be low when the disulfide and IMA levels were high in the patients with PE (p<0.05). When the IMA level was corrected by the albumin level (IMAR), the significant difference between the two groups disappeared. We also found that the native and total thiol concentrations were correlated with the systolic and diastolic blood pressures. The optimal cut-off values calculated for the prediction of PE were as follows: 178.45 µmol/L (with sensitivity of 72% and specificity of 83%) for native thiol, 232.55 µ mol/L (with a sensitivity of 75% and specificity of 85%) for total thiol, and 29.05 µmol/L (with sensitivity of 65% and specificity of 72%) for disulfide. The balance of thiol/disulfide may play a role in the pathogenesis of PE and could be used as a biological marker for PE.

21 January 2020 in Advances in Clinical and Experimental Medicine
Verified
Journal Article
Open access
CTCan Turkler
Can Turkler
TOTaylan Onat
Taylan Onat
EYEngin Yildirim
Engin Yildirim
SKSelcuk Kaplan
Selcuk Kaplan
GYGulce Naz Yazici
Gulce Naz Yazici
MSMukadder Sunar
Mukadder Sunar
Methotrexate (MTX) is an antineoplastic agent, which increases the level of reactive oxygen species (ROS) and decreases the level of antioxidants. Lycopene, is a potent antioxidant, which is used because of its protective effect against tissue damage. The aim of this study was to determine the effect of lycopene on ovarian MTX-induced injury in rats. Rats (n = 36) were randomly divided into 3 equal groups: a group with MTX only (MG, n = 12), a group with lycopene and MTX (LMG, n = 12), and a healthy control group (HCG, n = 12). Then, malondialdehyde (MDA), myeloperoxidase (MPO) and total glutathione (tGSH) levels and histopathological findings were examined in the ovaries of rats. Apart from the histopathological and biochemical evaluation, the reproductive performance of the experimental groups was also examined. Our study demonstrated that, in ovarian tissues of rats administered MTX, there was a decrease in the levels of tGSH, while MDA and MPO were increased, but it is observed that these ratios are reversed in the LMG (p < 0.05). It also has been proven that a single, high-dose use of MTX causes infertility in female rats, prolongs the gestation period and reduces the number of offspring. Lycopene pretreatment ameliorates the MTX induced ovarian injury and infertility in rats through its antioxidative activities.

10 October 2022 in Zeitschrift für Geburtshilfe und Neonatologie
Verified
Journal Article
Closed access
PDF file
EBEmre Baser
Emre Baser
NINihal Inandiklioglu
Nihal Inandiklioglu
DKDemet Aydogan Kırmızı
Demet Aydogan Kırmızı
FEFedi Ercan
Fedi Ercan
ACAyşen Caniklioğlu
Ayşen Caniklioğlu
EYEthem Serdar Yalvac
Ethem Serdar Yalvac
Objective Although the etiopathogenesis of preeclampsia (PE) is unknown, evidence suggests that it may be associated with increased oxidative stress. Studies have shown that oxidative stress can affect DNA fragments called telomeres. However, the interactions of PE, oxidative stress, and telomere length are not clearly known. This study aims to evaluate the oxidative/anti-oxidative stress balance in the placenta and umbilical cord and examine the effect of oxidative stress on telomeres. Materials-Method Cord blood and placental samples were collected from 27 pregnant women with severe PE (280/7–336/7 gestational weeks) and 53 healthy pregnant women. Telomere length (TL) was measured by real-time PCR in the cord blood and placenta tissue. Total antioxidant status (TAS) and total oxidant status (TOS) levels were measured in the cord blood and placenta tissue using a colorimetric method. Results No significant differences were found between groups regarding age, BMI, gravida, parity, and newborn gender (p>0.05). Cord blood and placental TL of PE patients were significantly shorter than the control group, while cord blood and placental TAS and TOS levels were higher (p<0.05). The results of a multivariate logistic regression analysis showed that the level of placental TOS in PE patients (OR=1.212, 95% CI=1.068–1.375) was an independent risk factor affecting PE. Conclusion This study found that oxidative stress is an independent risk factor in the development of PE and shortens TL in both placental and umbilical cord blood. Future research on telomere homeostasis may offer a new perspective for the treatment of PE. Received: 01 February 2022 Accepted after revision: 18 August 2022 Article published online: 10 October 2022 © 2022. Thieme. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany