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Dive into the research topics where Nihal Olgac Dundar is active.

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Featured researches published by Nihal Olgac Dundar.


Journal of Clinical Research in Pediatric Endocrinology | 2011

Prevalence of Metabolic Syndrome in Obese Children and Adolescents using Three Different Criteria and Evaluation of Risk Factors

Özlem Sangün; Bumin Dündar; Muhammet Köşker; Ozgur Pirgon; Nihal Olgac Dundar

Objective: To compare the prevalence of the metabolic syndrome (MS) in Turkish obese children and adolescents by using three different definitions and to assess the risk factors through a retrospective evaluation of anthropometric and laboratory parameters. Methods: Sixty hundred and fourteen obese patients (307 male, 307 female; mean age: 11.3±2.5 years) were included in the study. Medical history, physical examination, anthropometric measurements, results of biochemical and hormonal assays were obtained from the hospital records. MS was diagnosed according to the modified World Health Organization (WHO), Cook and the International Diabetes Federation (IDF) consensus criteria. Results: The prevalence of MS was found to be 39%, 34% and 33% according to the modified WHO, Cook and the IDF consensus criteria, respectively. MS prevalence in patients aged 12-18 years was significantly higher than that in patients between 7 and 11 years of age (p<0.05). Pubertal patients had a significantly higher MS prevalence than the non-pubertal cases (p<0.05). MS prevalence was also significantly higher in children who had a family history of heart disease, diabetes, obesity and hypertension as well as in those who had not been breast-fed (p<0.05). Conclusion: The use of the modified WHO criteria was found to result in a slightly higher prevalence rate for MS as compared to the other criteria. The prevalence of MS in our study population was higher than that reported in most previous studies in Turkey. A positive family history, puberty and not being breastfed in infancy were shown to be significant risk factors for MS in childhood. The prevalence of MS was found to be 39%, 34% and 33% according to the modified WHO, Cook and the IDF consensus criteria, respectively. MS prevalence in patients aged 12-18 years was significantly higher than that in patients between 7 and 11 years of age (p<0.05). Pubertal patients had a significantly higher MS prevalence than the non-pubertal cases (p<0.05). MS prevalence was also significantly higher in children who had a family history of heart disease, diabetes, obesity and hypertension as well as in those who had not been breast-fed (p<0.05). Conclusion: The use of the modified WHO criteria was found to result in a slightly higher prevalence rate for MS as compared to the other criteria. The prevalence of MS in our study population was higher than that reported in most previous studies in Turkey. A positive family history, puberty and not being breastfed in infancy were shown to be significant risk factors for MS in childhood. Conflict of interest:None declared.


Journal of Pediatric Endocrinology and Metabolism | 2005

Leptin levels in boys with pubertal gynecomastia

Bumin Dündar; Nihal Olgac Dundar; Tayfun Erci; Ece Böber; Atilla Büyükgebiz

BACKGROUND It has been reported that there is a relationship between circulating leptin and sex steroid hormones and leptin is able to stimulate estrogen secretion by increasing aromatase activity in adipose stromal cells and breast tissue. Leptin receptors have been also shown in mammary epithelial cells and it has been suggested that leptin is involved in the control of the proliferation of both normal and malignant breast cells. AIM To investigate circulating leptin levels in boys with pubertal gynecomastia. METHODS Twenty boys with pubertal gynecomastia who were in early puberty and had no obesity, and 20 healthy individuals matched for age, pubertal stage and body mass index (BMI) with the study group, were enrolled in the study. Body weight, height and left midarm circumference (MAC) and left arm triceps skinfold thickness (TSF) were measured and BMI was calculated. A fasting blood sample was collected and routine hormonal parameters including prolactin, beta-human chorionic gonadotropin (betaHCG), total and free testosterone, estradiol, luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, androstenedione (AS) and dehydroepiandrosterone sulfate (DHEAS) levels were studied. Serum leptin levels were analyzed using radioimmunoassay. RESULTS The mean ages of the study and control group were not different (13.9 +/- 0.89 and 14.2 +/- 0.66, respectively). No significant difference was found for BMI, MAC and TSF values between the two groups. There was no significant difference for hormonal parameters including FSH, LH, total and free testosterone, estradiol, AS, DHEAS and estradiol/total testosterone ratio between boys with pubertal gynecomastia and the controls. Serum leptin levels were found significantly higher in the study group compared with the healthy controls (5.58 +/- 0.81 and 2.39 +/- 0.29 ng/ml, respectively; p <0.001). No correlation could be determined between serum leptin levels and hormonal parameters. CONCLUSION The presence of higher leptin levels in boys with pubertal gynecomastia indicates that leptin may be involved in the pathogenesis of pubertal gynecomastia. The role of circulating leptin in pubertal gynecomastia is probably related to increase in estrogen and/or estrogen/ androgen ratio by the stimulating effect of leptin on aromatase enzyme activity in both adipose and breast tissues, or a direct growth stimulating effect of leptin on mammary epithelial cells, or increase in sensitivity of breast epithelial cells to estrogen with inducing functional activation of estrogen receptors by leptin in breast tissue.


Journal of Clinical Research in Pediatric Endocrinology | 2014

Adipokines in Breast Milk: An Update

Gönül Çatlı; Nihal Olgac Dundar; Bumin Dündar

Epidemiological surveys indicate that nutrition in infancy is implicated in the long-term tendency to obesity and that a longer duration of breastfeeding is associated with a protective effect against metabolic disorders later in life. However, the precise cause of this association is not well understood. Recent studies on the compounds present in human breast milk have identified various adipokines, including leptin, adiponectin, resistin, obestatin, nesfatin, ghrelin and apelins. Some of these compounds are involved in the regulation of food intake and energy balance. The presence of these adipokines in breast milk suggests that they may be responsible for the regulation of growth in early infancy and that they could influence the energy balance and development of metabolic disorders in childhood and adulthood.


Pediatrics International | 2010

Ghrelin and adiponectin levels in colostrum, cord blood and maternal serum

Nihal Olgac Dundar; Bumin Dündar; Gokhan Cesur; Nigar Yilmaz; Recep Sutcu; Fehmi Ozguner

Background:  Ghrelin and adiponectin, which are considered to take part in the regulation of energy metabolism, have been found in breast milk and cord blood. The aims of this study were to determine ghrelin and adiponectin levels in colostrum, cord blood and maternal serum and to investigate the correlations between colostrum and cord blood levels of these peptides and the anthropometry of newborn infants and their mothers.


Seizure-european Journal of Epilepsy | 2016

The efficacy, tolerability and safety of levetiracetam therapy in a pediatric population

Hasan Tekgul; Pinar Gencpinar; Dilek Çavuşoğlu; Nihal Olgac Dundar

PURPOSE The purpose of this study was to assess the efficacy and safety of levetiracetam monotherapy in a pediatric population. METHOD A retrospective review was performed of the charts of 351 consecutive children who were 6 months to 18 years of age and were treated with levetiracetam. Levetiracetam monotherapy was initiated and dosed to efficacy or unacceptable side effects, with a range of 10-112 mg/kg/day. Electroencephalographic examination was performed at pre-treatment and 12th months in the post-treatment period. Following the commencement of levetiracetam treatment, the retention rate at 3, 6 and 12 months was 100%, 75% and 57%, respectively. RESULTS The monotherapy retention rate at 3 and 12 months following the commencement of levetiracetam treatment was (231/351, 66%), and (126/200, 63%) respectively. A total of 165 (47%) patients had idiopathic epilepsy and 186 patients (53%) had symptomatic-cryptogenic epilepsy. The >90% seizure reduction rate was 65%, and the 50-90% seizure reduction rate was 14% at the 3rd month of treatment. Similarly, the >90% seizure reduction rate was 63%, and the 50-90% seizure reduction rate was 15% at the 12th month of treatment. EEG improvement (normalization of EEG) was observed in 65 (47%) patients. Overall, 61 (17%) patients showed adverse events. The most reported side effects were irritability (67%), hyperactivity (8%), somnolence (6%), behavioral disorders (5%), restlessness (5%), increased seizure frequency (3%), enuresis (2%), headache (2%) and attempted suicide (2%). CONCLUSION The retrospective study of 231 consecutive pediatric patients to confirm that levetiracetam is effective as initial monotherapy for different types of seizures and/or epilepsy syndromes. However there is still a need for well-designed trials to justify the widespread use of levetiracetam monotherapy in children with specific epilepsy syndromes.


Neurology International | 2013

Interleukin-1β secretion in hippocampal sclerosis patients with mesial temporal lobe epilepsy

Nihal Olgac Dundar; Berrin Aktekin; Nilufer Cicek Ekinci; Duygu Sahinturk; Ugur Yavuzer; Olcay Yegin; Senay Haspolat

Mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) is a common medically intractable epilepsy syndrome. Although pathogenesis of HS still remains highly controversial, genetics may play a role as a predisposing factor. Previous evidence in a Japanese population revealed that the homozygotes for allele T at position -511 of the interleukin (IL)-1β gene promoter region (IL-1β-511 T/T) confers susceptibility to the development of HS. However, whether this polymorphism has an effect on IL-1β levels in MTLEHS patients was not demonstrated. This study aimed to analyze the distribution of this particular polymorphism in a group of Turkish HS patients and correlate the polymorphism with IL-1β secretion from the lymphocytes, thus revealing a functional role for IL-1β in the etiopathogenesis of HS. A single base pair polymorphism at position –511 in the promoter region of the IL-1β gene was analyzed. The spontaneous and 1 ng/mL lipopolysaccharidestimulated production of IL-1β by peripheral blood mononuclear cells after 4 and 24 h of incubation were measured by ELISA method. The heterozygous type (–511 C/T) was the most common genotype. There was no difference in frequency of allele –511 T between patients and controls. Analysis of IL-1β levels, genotype and allele distributions showed no significant difference among the groups (P>0.05). Nevertheless, it was seen that patients who carry a T allele at position -511 of the IL-1β gene had increased IL-1β levels. T-allele carriage may be important. Only IL-1β secretion from the lymphocytes has been assessed in this study. Considering the importance of IL-1β in the etiopathogenesis of HS, further studies are needed to evaluate locally produced IL-1β levels.


Epilepsy & Behavior | 2016

Electrical status epilepticus in sleep (ESES)/continuous spikes and waves during slow sleep (CSWS) syndrome in children: An electroclinical evaluation according to the EEG patterns.

Pinar Gencpinar; Nihal Olgac Dundar; Hasan Tekgul

OBJECTIVE The aim of this study was to describe the electroclinical spectrum in children with electrical status epilepticus in sleep (ESES)/continuous spikes and waves during slow sleep (CSWS) syndrome according to the EEG patterns. METHODS Clinical data of 44 patients with ESES/CSWS syndrome who were treated and followed at least two years were analyzed. Records of EEGs of patients were reevaluated to determine two aspects of the ESES pattern: (1) the spike-wave index (SWI) on the NREM sleep EEG (Group I: typical vs. atypical ESES pattern (33/11 patients)) and (2) the area of maximum amplitude of continuous epileptic activity (Group II: anterior vs. posterior ESES pattern (33/11 patients)). RESULTS Symptomatic etiology was more defined in patients with the typical ESES pattern (40%) than the group with the atypical ESES pattern (9%) by a factor of four. All patients were receiving at least two antiepileptic drug (AED) treatments. Eighteen patients (41%) received AEDs plus ACTH therapy. Complete disappearance of the ESES pattern on the EEG was observed in 18 patients (41%), more than 50% reduction was observed in five patients (11%), less than 50% reduction was observed in eight patients (18%), and no response was observed in five patients (11%). No significant difference was found when comparing the groups in terms of reduction of seizures and the SWI. Seizure outcome at the two-year follow-up was similar between the group with ESES treated with AEDs plus ACTH and the group with ESES treated with AEDs without ACTH therapy. SIGNIFICANCE This study demonstrated that the rate of the SWI (typical vs. atypical ESES) and the maximum amplitude of the ESES pattern (anterior vs. posterior) have no significant correlation with seizure control and reduction of the SWI on the EEG in children with ESES syndrome.


Journal of Clinical Research in Pediatric Endocrinology | 2015

The Effects of Six-Month L-Thyroxine Treatment on Cognitive Functions and Event-Related Brain Potentials in Children with Subclinical Hypothyroidism

Özlem Sangün; Serpil Demirci; Nihal Olgac Dundar; Ozgur Pirgon; Tugba Koca; Melike Doğan; Bumin Dündar

Objective: The aim of this study was to investigate the cognitive status of children with subclinical hypothyroidism (SH) before and after L-thyroxine (L-T4) treatment using event-related potentials (ERPs) and neuropsychological tests. Methods: This prospective study was conducted on a series of 20 children with mild SH (free T4 normal and thyroid-stimulating hormone level within 5-10 µIU/L) who underwent clinical and cognitive assessment before L-T4 treatment and 6 months afterwards. The recordings of ERPs were done at the time of diagnosis and after 6 months of euthyroid state. Neuropsychiatric tests for attention, perception, close and remote memory were performed on all patients and on the control group which consisted of 20 healthy children of normal intelligence. Results: While pretreatment verbal memory (VM) and verbal recall (VR) scores of the SH group were significantly lower than those of the control group (p=0.004 and 0.012, respectively), no significant differences between the post-treatment and control groups were found in these scores after 6 months of L-T4 treatment. Post-treatment VM and VR scores were significantly higher than the pretreatment scores in the SH group (p=0.008 and p=0.0001). There were no significant differences between the pre-and post-treatment values of electrophysiological evaluation in N1, P2, P3 latencies or P3 amplitude (p>0.05), although there was a significant decrease in N2 latency in the post-treatment group (p=0.03). Conclusion: SH affects cognition in children and L-T4 replacement therapy leads to normalization of cognitive functions. Neuropsychological tests can be used as complementary measures in the evaluation of children with SH. Determining the association between ERPs and SH would contribute to the comprehensive evaluation of these children.


Journal of Child Neurology | 2017

Efficacy of Low-Dose Corticosteroid Therapy Versus High-Dose Corticosteroid Therapy in Bell’s Palsy in Children

Pinar Arican; Nihal Olgac Dundar; Pinar Gencpinar; Dilek Çavuşoğlu

Bell’s palsy is the most common cause of acute peripheral facial nerve paralysis, but the optimal dose of corticosteroids in pediatric patients is still unclear. This retrospective study aimed to evaluate the efficacy of low-dose corticosteroid therapy compared with high-dose corticosteroid therapy in children with Bell’s palsy. Patients were divided into 2 groups based on the dose of oral prednisolone regimen initiated. The severity of idiopathic facial nerve paralysis was graded according to the House-Brackmann Grading Scale. The patients were re-assessed in terms of recovery rate at the first, third, and sixth months of treatment. There was no significant difference in complete recovery between the 2 groups after 1, 3, and 6 months of treatment. In our study, we concluded that even at a dose of 1 mg/kg/d, oral prednisolone was highly effective in the treatment of Bell’s palsy in children.


Journal of Pediatric Endocrinology and Metabolism | 2012

Primary hypogonadism in a case with XLAG syndrome.

Özmert M.A. Özdemir; Murat Çağlar; Ali Koçyiğit; Nihal Olgac Dundar; Özlem Sangün; Bumin Dündar

Abstract Patients with X-linked lissencephaly with ambiguous genitalia (XLAG) syndrome present with lissencephaly, agenesis of the corpus callosum, refractory epilepsy of neonatal onset, microcephaly, and male genotype with ambiguous genitalia. The basis of the ambiguous genitalia in XLAG syndrome is not well-known. We report a case of the fourth child of healthy consanguineous parents who was presented to the hospital because of non-febrile seizures at 2 months of life. On physical examination, microcephaly, some dysmorphic face features, and ambiguous genitalia were determined. The cranial magnetic resonance imaging of the patient showed lissencephaly, agenesis of the corpus callosum, and enlarged ventricles. His karyotype was 46, XY. He had undetectable testosterone levels and elevated gonadotropins. Neither testicular tissue nor any testosterone response to human chorionic gonadotropin stimulation test was observed. These findings suggest that the hypogonadism in this patient with XLAG syndrome is primary hypogonadism due to gonadal agenesis or dysgenesis.

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Özlem Sangün

Süleyman Demirel University

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Nurullah Bolat

Çanakkale Onsekiz Mart University

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Dilek Cavusoglu

Afyon Kocatepe University

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Faruk Öktem

Süleyman Demirel University

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Fehmi Ozguner

Süleyman Demirel University

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Gokhan Cesur

Süleyman Demirel University

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