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Featured researches published by Gönül Tezel.


Pediatric Neurology | 2013

The Effects of Intraperitoneal Pentoxifylline Treatment in Rat Pups With Hypoxic-Ischemic Encephalopathy

Salih Kalay; Osman Öztekin; Gönül Tezel; Hakan Aldemir; Emel Sahin; Sadi Köksoy; Mustafa Akcakus; Nihal Oygür

BACKGROUND The aim of this study was to evaluate the effects of postischemic treatment with pentoxifylline on the cytokine gene expressions and neuronal apoptosis in neonatal rat model of hypoxic-ischemic encephalopathy. METHODS Seven-day-old Wistar rat pups (n = 40) of either sex, delivered spontaneously, were used in this experimental study. Control group (n = 8): after median neck incision was made, neither ligation nor hypoxia was performed, ischemia group (n = 16): 0.5 mL of saline was injected intraperitoneally immediately after hypoxia. Pentoxifylline and ischemia groups (n = 16): the rat pups were administered intraperitoneally 60 mg/kg of pentoxifylline immediately after hypoxia. Eight rats from ischemia and pentoxifylline + ischemia groups were sacrificed 4 and 24 hours after drug administration. Control group mice were decapitated 4 hours after hypoxia. Caspase-3 activity, interleukin-1β, and tumor necrosis factor-α messenger RNA expression levels were studied in the left half of the brain. RESULTS Induction of cerebral ischemia increased tumor necrosis factor-α and interleukin-1β messenger RNA expression levels significantly at 4 hours and 24 hours following ischemia in the left ischemic hemispheres in the ischemia group as compared with the control group. Systemic administration of pentoxifylline immediately after hypoxic-ischemic encephalopathy significantly reduced the tumor necrosis factor-α and interleukin-1β messenger RNA expression levels in ischemic tissue as compared with the ischemia group. Caspase-3 activities in the left half of the brains of ischemia group were found to be increased significantly as compared with control group. Caspase-3 activities in the brains of pentoxifylline + ischemia groups were significantly lower than in that of ischemia group. CONCLUSIONS Based on the significantly lower interleukin-1β and tumor necrosis factor-α gene expression measured after 4 and 24 hours and significantly reduced caspase-3 activity measured colorimetrically in the animals treated with pentoxifylline, our findings suggest that pentoxifylline may reduce brain damage due to hypoxic-ischemic injury.


Experimental and Therapeutic Medicine | 2014

Role of immunoglobulin in neuronal apoptosis in a neonatal rat model of hypoxic ischemic brain injury

Salih Kalay; Osman Öztekin; Gönül Tezel; Hakan Aldemir; Emel Sahin; Sadi Köksoy; Mustafa Akcakus; Nihal Oygür

The objective of the present study was to evaluate the neuroprotective effects of immunoglobulin (Ig) in a neonatal hypoxic ischemic (HI) rat model. Seven-day-old rat pups were randomly assigned to control, hypoxia and hypoxia + Ig groups. The rats in the hypoxia +Ig group were intraperitoneally administered 1 g/kg Ig once, immediately after hypoxia. Saline was administered to the rats in the hypoxia group at the same time point. Eight rats from each of the Ig + hypoxia and hypoxia groups were sacrificed by decapitation 4 and 24 h following the administration of Ig or saline. The rats of the control group were sacrificed at the 4 h time-point. Caspase-3 activity, as well as IL-1β, IL-6 and TNF-α mRNA expression levels, were studied in the left ischemic hemispheres. Induction of cerebral ischemia increased the TNF-α, IL-6 and IL-1β mRNA expression levels significantly at 4 and 24 h in the left ischemic hemispheres in the hypoxia group compared with those in the control group. The systemic administration of Ig following HI encephalopathy significantly reduced the TNF-α, IL-6 and IL-1β mRNA expression levels in the ischemic tissue in the Ig + hypoxia group compared with those in the hypoxia group. In the hypoxia group, caspase-3 activity in the left half of the brain was found to be significantly increased compared with that in the control group. Caspase-3 activity in the Ig + hypoxia group was significantly lower than that in the hypoxia group. The observations of the present study indicate that Ig administration may be an efficient treatment approach for reducing cerebral apoptosis associated with hypoxic ischemia.


Journal of Maternal-fetal & Neonatal Medicine | 2013

The role of VEGF and its soluble receptor VEGFR-1 in preterm newborns of preeclamptic mothers with RDS

Salih Kalay; Burak Cakcak; Osman Öztekin; Gönül Tezel; Ozgur Tosun; Mustafa Akcakus; Nihal Oygür

Abstract Objective: We measured vascular endothelial growth factor (VEGF) and soluble VEGF receptor 1(sVEGFR-1) concentrations in cord blood and tracheal aspirate fluid (TAF) in order to investigate the role of them in lung maturation and the severity of respiratory distress syndrome (RDS) in preterm newborns, born to preeclamptic mothers. Methods: Newborns were divided into two groups as preterms born to preeclamptic mothers and preterms born to healthy mothers. They were also divided into two groups as severe RDS (sRDS) and mild RDS (mRDS) according to the need of surfactant and extent or type of ventilatory support. The concentrations of VEGF and sVEGFR-1 in cord blood and TAF (only in preterms with sRDS) were assayed by standardized enzyme-linked immunosorbent assay. Results: When the patients were evaluated as sRDS and mRDS, cord blood VEGF and VEGF/sVEGFR-1 concentrations of preterms with sRDS were significantly lower than the concentrations of preterms with mRDS. Conversely, cord blood sVEGFR-1 concentrations of preterms with sRDS were significantly higher than the concentrations of preterms with mRDS. VEGF and sVEGFR-1 concentrations in TAF could be compared only between sRDS preterms, born to preeclampsia (+) and (−) mothers. No statistical significance was detected between the two groups when sVEGFR-1, VEGF and VEGF/sVEGFR-1 concentrations in TAF were compared. Conclusion: Preeclampsia seems not to have an important effect on VEGF and sVEGFR-1 concentrations of preterm newborns both in cord blood and in TAF. Low VEGF and high sVEGFR-1 concentrations seem to be associated with the severity of RDS irrespective of preeclampsia, suggesting that VEGF may be one of the main components of lung maturation.


Journal of Maternal-fetal & Neonatal Medicine | 2014

Is the strength of direct antiglobulin test important for the duration of phototherapy

Osman Öztekin; Salih Kalay; Gönül Tezel; Ebru Barsal; Selen Bozkurt; Mustafa Akcakus; Nihal Oygür

Abstract The purpose of this study was to evaluate the relationship between the grades of positivity of the direct antiglobulin test (DAT) and their effects on the duration of phototherapy for neonatal jaundice. DAT reactions of blood samples were graded as (1+), (2+), (3+) and (4+). DAT was positive in 80 neonates who were exposed to phototherapy due to jaundice. Patients with positive DAT reactions are classified in the study as follows: 34 newborns were DAT (1+), 18 newborns were DAT (2+), 16 newborns were DAT (3+) and 12 newborns were DAT (4+). We found that higher grades of positivity of DAT are associated with extended duration of phototherapy (r = 0.436, p < 0.05). Additionally, DAT (4+) reactions are more predictive for a prolonged duration of phototherapy requirement than the other grades (p < 0.0001).


Turk Pediatri Arsivi-turkish Archives of Pediatrics | 2013

Yenidoğanın geçici takipnesinde epiteliyal sodyum kanalı alfa alt biriminin sentezinden sorumlu SCNN1A geninin değerlendirilmesi

Osman Öztekin; Mahmut Akyol; Salih Kalay; Gönül Tezel; Mustafa Akcakus; Nihal Oygür

Sum mary Aim: Epithelial sodium channels play an important role in the regulation of movement of sodium and absorption of alveolar fluid during prenatal period. Transient tacyhpnea of the newborn is a common respiratory problem in term or near-term infants. A lack of maturation of epithelial sodium channels is considered in its etiology. However, the role of genetic factors is unclear. The purpose of this study is to determine the role of gene SCNN1A which is responsible for synthesis of epithelial sodium channel alpha unit which is known to be effective in the mechanism of the disorder. Material and Method: Newborn infants>37 weeks of gestation with a diagnosis of transient tacyhpnea of the newborn followed up at Neonatal Intensive Care Unit of Akdeniz University Medical Faculty between July 2010 January 2012 and a control group consisting of healthy infants at the same gestational age were included in the study. 2 cc of blood with EDTA was obtained from both groups in the first five days of their life and blood samples were kept at -80 ̊ degree. DNA isolation was fulfilled in the Department of Medical Biology. The gene was displayed using BigDye Terminator with the method of Sanger sequencing. The study was approved by the ethics commite (B.30.2.AKD.0.20.05.05). Results: Both the transient tacyhpnea of the newborn group and the control group were consisted of 32 infants. Through the sequence display method, all the exons of the SCNN1A gene which codes the alpha subunit of epithelial sodium channels were displayed. Nevertheless, no significant change was found. Conclusions: In conclusion, no relationship was established between the development of transient tacyhpnea of the newborn and the SCNN1A gene which is responsible for the synthesis of alpha subunit of epithelial sodium channels. However, this preliminary study is considered to be a threshold for an extended research with a wider range of patients to obtain more precise results. (Turk Arch Ped 2013; 48: 35-39)


Journal of Clinical Pharmacy and Therapeutics | 2013

Chemotherapy for transient myeloproliferative disorder in a premature infant with Down syndrome.

Osman Öztekin; Salih Kalay; Gönül Tezel; F. Tayfun; A. Kupesiz; M. Hangul; Mustafa Akcakus; Nihal Oygür

Congenital leukaemia is the most common leukaemia in newborns with Down syndrome, but it must be differentiated from transient myeloproliferative disorder. The majority of transient myeloproliferative disorders regresses spontaneously during the first few months of life. Data on the treatment outcomes of transient myeloproliferative disorder in premature infants are very rare. We present a case of a very‐low‐birthweight (1350 g) premature newborn with Down syndrome, diagnosed as having transient myeloproliferative disorder and treated with chemotherapy due to recurrent hyperleucocytosis (WBC: 148 000/mm³) after repeated exchange transfusions.


African Journal of Paediatric Surgery | 2013

Octreotide treatment in a neonate with non-chylous pleural effusion

Salih Kalay; Osman Öztekin; Gönül Tezel; Burak Emre Demir; Mustafa Akcakus; Nihal Oygür

Fetal pleural effusion is a rare condition. While it may regress spontaneously, it may also continue up to the post-natal period. This condition may be treated by thoracentesis, thoracoabdominal shunt application and pleurodesis in the intrauterine period while thoracentesis or tube thoracostomy may be used in the post-natal period. In cases where the fluid is defined to represent chylothorax, octreotide, a somatostatin analogue, may be administered for treatment. In this case report, we discussed the outcomes of treatment with octreotide administered in a neonatal case under follow-up due to fetal pleural effusion and with non-chylous ascites detected in the post-natal period.


American Journal of Perinatology Reports | 2011

Cerebellar Herniation after Lumbar Puncture in Galactosemic Newborn

Salih Kalay; Osman Öztekin; Gönül Tezel; Mustafa Akcakus; Nihal Oygür

Cerebral edema resulting in elevated intracranial pressure is a well-known complication of galactosemia. Lumbar puncture was performed for the diagnosis of clinically suspected bacterial meningitis. Herniation of cerebral tissue through the foramen magnum is not a common problem in neonatal intensive care units because of the open fontanelle in infants. We present the case of a 3-week-old infant with galactosemia who presented with signs of cerebellar herniation after lumbar puncture.


American Journal of Perinatology Reports | 2014

Microvillus inclusion disease associated with necrotizing enterocolitis in a premature infant.

Ersin Sayar; Salih Kalay; Aygen Yilmaz; Osman Öztekin; Ali Islek; Gülsüm Özlem Elpek; Zuhal Kalay; Gönül Tezel; Reha Artan

Microvillus inclusion disease is one of the congenital diarrheal disorders characterized by the appearance of inclusion bodies on the intestinal epithelium. To date there are a few cases and also a few other associated finding reports related to this life-threatening disease in literature. In this report, we present a premature infant with microvillus inclusion disease that was associated with necrotizing enterocolitis. Thus, we should be aware of the appearance of necrotizing enterocolitis in patients with microvillus inclusion disease, especially when contributing factors are present.


Journal of Maternal-fetal & Neonatal Medicine | 2013

Investigation of the serum glucocorticoid kinase 1 gene in patients with transient tachypnea of the newborn.

Osman Öztekin; Mahmut Akyol; Salih Kalay; Gönül Tezel; Mustafa Akcakus; Nihal Oygür

Abstract Objective: The aim of this study was to investigate whether there is a role of the serum glucocorticoid kinase (SGK) 1 gene, which has an effect on the control of the epithelial sodium channels. Materials and method: This study included patients who were diagnosed with transient tachypnea of the newborn (TTN) with more than 37 weeks of gestation. As the control group, healthy newborns of the same gestational age were included. From each group, within the first 5 d of their lives, 2 cc of whole blood was taken in EDTA tubes, and stored at −80 °C. The DNA extraction was performed. Results: There were 32 patients in the TTN, and also 32 patients in the control group. The heterozygous allele rs1057293 (3/28) and rs1743966 (8/28) were located in the encoder region of the SGK 1 gene. In addition, in encoding region of the SGK 1 gene, the Arg97Ile (1/28), which causes the amino acid changes, had a genotype frequency of 0.0357, and a mutation was identified in Arg97Ile. Discussion: We have defined polymorphisms rs1057293 and rs1743966 in the SGK 1 gene, and the Arg97Ile mutation, for the first time in patients with TTN. This pilot study gave us some clues about a genetic basis of TTN phenotype, next to the lack of the pulmonary maturation.

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