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Dive into the research topics where Zehra Aycan is active.

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Featured researches published by Zehra Aycan.


The Journal of Clinical Endocrinology and Metabolism | 2016

Rare Causes of Primary Adrenal Insufficiency: Genetic and Clinical Characterization of a Large Nationwide Cohort

Tulay Guran; Federica Buonocore; Nurcin Saka; Mehmet Nuri Özbek; Zehra Aycan; Abdullah Bereket; Firdevs Bas; Sukran Darcan; Aysun Bideci; Ayla Güven; Korcan Demir; Aysehan Akinci; Muammer Buyukinan; Banu Kucukemre Aydin; Serap Turan; Sebahat Yılmaz Ağladıoğlu; Zeynep Atay; Zehra Yavas Abali; Omer Tarim; Gönül Çatlı; Bilgin Yuksel; Teoman Akcay; Metin Yildiz; Samim Ozen; Esra Döğer; Huseyin Demirbilek; Ahmet Uçar; Emregul Isik; Bayram Özhan; Semih Bolu

Context: Primary adrenal insufficiency (PAI) is a life-threatening condition that is often due to monogenic causes in children. Although congenital adrenal hyperplasia occurs commonly, several other important molecular causes have been reported, often with overlapping clinical and biochemical features. The relative prevalence of these conditions is not known, but making a specific diagnosis can have important implications for management. Objective: The objective of the study was to investigate the clinical and molecular genetic characteristics of a nationwide cohort of children with PAI of unknown etiology. Design: A structured questionnaire was used to evaluate clinical, biochemical, and imaging data. Genetic analysis was performed using Haloplex capture and next-generation sequencing. Patients with congenital adrenal hyperplasia, adrenoleukodystrophy, autoimmune adrenal insufficiency, or obvious syndromic PAI were excluded. Setting: The study was conducted in 19 tertiary pediatric endocrinology clinics. Patients: Ninety-five children (48 females, aged 0–18 y, eight familial) with PAI of unknown etiology participated in the study. Results: A genetic diagnosis was obtained in 77 patients (81%). The range of etiologies was as follows: MC2R (n = 25), NR0B1 (n = 12), STAR (n = 11), CYP11A1 (n = 9), MRAP (n = 9), NNT (n = 7), ABCD1 (n = 2), NR5A1 (n = 1), and AAAS (n = 1). Recurrent mutations occurred in several genes, such as c.560delT in MC2R, p.R451W in CYP11A1, and c.IVS3ds+1delG in MRAP. Several important clinical and molecular insights emerged. Conclusion: This is the largest nationwide study of the molecular genetics of childhood PAI undertaken. Achieving a molecular diagnosis in more than 80% of children has important translational impact for counseling families, presymptomatic diagnosis, personalized treatment (eg, mineralocorticoid replacement), predicting comorbidities (eg, neurological, puberty/fertility), and targeting clinical genetic testing in the future.


Journal of Pediatric Endocrinology and Metabolism | 2002

Mutations of the 5alpha-steroid reductase type 2 gene in six Turkish patients from unrelated families and a large pedigree of an isolated Turkish village.

Gönül Öcal; Pelin Adiyaman; Merih Berberoglu; E Cetinkaya; Nejat Akar; A Uysal; Türker Duman; Olcay Evliyaoglu; Zehra Aycan; S Lumbroso; C Sultan; S Lumbrasso

We describe six Turkish patients with 5alpha-steroid reductase type 2 deficiency from unrelated Turkish families and a large pedigree of one of these patients who reside north-west of Anatolia. Patients NA, KS, BD and SY presented for evaluation of bilateral inguinal masses with female phenotypes. Patient ABE had penoscrotal hypospadias with male phenotype. Homozygous mutation of the 5alphaSR2 gene was identified in five of these patients by genomic DNA analysis. These mutations were Leu55Gln in exon 1 (in patients FG, BD and ABE), deltaMet157 in exon 3 (in patient NA), and splice junction abnormality in intron 1 (in patient SY). One individual (patient KS) was found to be a compound heterozygous carrier of two different mutations, Leu55Gln in exon 1 and Arg171Ser in exon 3. Patient FG had a large pedigree with the Leu55Gln mutation in exon 1. The pedigree of this family with marital consanguinity is remarkable, and possibly due to the isolation of this family because of economic and social problems. A further 85 individuals belonging to this family were analyzed for exon 1 Leu55Gln mutations in the 5alphaSR2 gene. Forty-two of these 85 individuals (49.41%) had this alteration; 11 were homozygous (8 genetic male, 3 genetic female) and 31 heterozygous (18 genetic male, genetic female) for this mutation. It was interesting to see asymptomatic homozygous female carriers. In conclusion, according to our results and those of other Turkish patients reported by different investigators, 5aSR2 gene mutation analysis, especially for Leu55Gln in exon 1 and deltaMet157 in exon 3, must be carried out in Turkish patients with male pseudohermaphroditism. Homozygous asymptomatic female carriers must be taken into consideration in this clinical entity, especially in a closed population, because of the risk of transmitting the disease to their offspring.


Clinical Endocrinology | 2010

Novel TSHR mutations in consanguineous families with congenital nongoitrous hypothyroidism.

Hakan Cangul; Neil V. Morgan; Julia R. Forman; Halil Saglam; Zehra Aycan; Tahsin Yakut; Tuna Gulten; Omer Tarim; Ece Böber; Yaşar Cesur; Gail Kirby; Shanaz Pasha; Mutlu Karkucak; Erdal Eren; Semra Çetinkaya; Veysel Nijat Baş; Korcan Demir; Sevil Arı Yuca; Esther Meyer; Michaela Kendall; Wolfgang Högler; Timothy Barrett; Eamonn R. Maher

Objective  Nonsyndromic autosomal recessively inherited nongoitrous congenital hypothyroidism (CHNG) can be caused by mutations in TSHR, PAX8, TSHB and NKX2‐5. We aimed to investigate mutational frequencies of these genes and genotype/phenotype correlations in consanguineous families with CHNG.


Journal of Clinical Research in Pediatric Endocrinology | 2014

Prader-Willi Syndrome and Growth Hormone Deficiency

Zehra Aycan; Veysel Nijat Baş

Prader-Willi syndrome (PWS) is a rare multisystem genetic disorder demonstrating great variability with changing clinical features during patient’s life. It is characterized by severe hypotonia with poor sucking and feeding difficulties in early infancy, followed by excessive eating and gradual development of morbid obesity in later infancy or early childhood. The phenotype is most probably due to hypothalamic dysfunction which is also responsible for growth hormone (GH) and thyroid-stimulating hormone (TSH) deficiencies, central adrenal insufficiency and hypogonadism. The multidimensional problems of patients with PWS can be managed with multidisciplinary approach. Reduced GH secretion, low peak GH response to stimulation, decreased spontaneous GH secretion and low serum IGF-1 levels in PWS patients have been documented in many studies. GH therapy has multiple beneficial effects on growth and body composition, motor and mental development in PWS patients. The recommended dosage for GH is 0.5-1 mg/m2/day. GH therapy should not be started in the presence of obstructive sleep apnea syndrome, adenotonsillar hypertrophy, severe obesity and diabetes mellitus. GH treatment should be considered for patients with genetically confirmed PWS in conjunction with dietary, environmental and life-style measures.


Hormone Research in Paediatrics | 2007

Effects of Growth Hormone on Growth, Insulin Resistance and Related Hormones (Ghrelin, Leptin and Adiponectin) in Turner Syndrome

Feyza Darendeliler; Zehra Aycan; Ergun Çetinkaya; Sadi Vidilisan; Firdevs Bas; Aysun Bideci; Fatma Demirel; Sukran Darcan; Atilla Büyükgebiz; Metin Yildiz; Merih Berberoglu; Ilknur Arslanoglu; Rüveyde Bundak

Background:Concomitant evaluation of the metabolic and growth-promoting effects of growth hormone (GH) therapy in Turner syndrome (TS) may be used in the prediction of the growth response to GH therapy. Aim: To evaluate the metabolic effects of GH therapy in TS and correlation with the short-term growth response. Patients: 24 prepubertal children with TS, aged 9.4 ± 2.6 years were followed for auxology and IGF-I, IGFBP-3, leptin, ghrelin, adiponectin, lipids and OGTT results in a prospective multicenter study. Intervention: GH (Genotropin®) in a dose of 50 µg/kg/day for 1 year. Results: Height standard deviation score (SDS) increased from –3.9 ± 1.5 to –3.5 ± 1.4 (p = 0.000) on therapy. BMI did not change. IGF-I SDS increased from –2.3 ± 0.4 to –1.6 ± 1.1 at 3 and 6 months (p = 0.001) and decreased thereafter. Serum leptin decreased significantly from 2.3 ± 3.9 to 1.7 ± 5.3 ng/ml (p = 0.022) at 3 months and increased afterwards. Serum ghrelin decreased from 1.2 ± 0.8 to 0.9 ± 0.4 ng/ml (p = 0.005) with no change in adiponectin. Basal and stimulated insulin levels also increased significantly. Δ height SDS over 1 year showed a significant correlation with Δ IGF-I0–3 months (r = 0.450, p = 0.027). Conclusion: IGF-I may be considered as a marker of growth response in TS at short term. Leptin shows a decrease at short term but does not have a correlation with growth response. The decrease in ghrelin in face of unchanged weight seems to be associated with increase in IGF-I and insulin levels. The unchanged adiponectin levels in spite of an increase in insulin levels indicates that adiponectin is mainly affected by weight, not insulin.


Clinical Endocrinology | 2013

Thyroid dyshormonogenesis is mainly caused by TPO mutations in consanguineous community

Hakan Cangul; Zehra Aycan; Álvaro Olivera-Nappa; Halil Saglam; Nadia Schoenmakers; Kristien Boelaert; Semra Çetinkaya; Omer Tarim; Ece Böber; Feyza Darendeliler; Veysel Nijat Baş; Korcan Demir; Banu Kucukemre Aydin; Michaela Kendall; Trevor Cole; Wolfgang Högler; V. Krishna Chatterjee; Timothy Barrett; Eamonn R. Maher

In this study, we aimed to investigate the genetic background of thyroid dyshormonogenesis (TDH).


Journal of Clinical Research in Pediatric Endocrinology | 2010

Insulin Oedema in Newly Diagnosed Type 1 Diabetes Mellitus

Veysel Nijat Baş; Semra Çetinkaya; Sebahat Yılmaz Ağladıoğlu; Havva Nur Peltek Kendirici; Hatice Bilgili; Nurdan Yıldırım; Zehra Aycan

Despite the essential role of insulin in the management of patients with insulin deficiency, insulin use can lead to adverse effects such as hypoglycaemia and weight gain. Rarely, crucial fluid retention can occur with insulin therapy, resulting in an oedematous condition. Peripheral or generalised oedema is an extremely rare complication of insulin therapy in the absence of heart, liver or renal involvement. It has been reported in newly diagnosed type 1 diabetes, in poorly controlled type 2 diabetes following the initiation of insulin therapy, and in underweight patients on large doses of insulin. The oedema occurs shortly after the initiation of intensive insulin therapy. We describe two adolescent girls with newly diagnosed type 1 diabetes, who presented with oedema of the lower extremities approximately one week after the initiation of insulin treatment; other causes of oedema were excluded. Spontaneous recovery was observed in both patients. Conflict of interest:None declared.


Endocrine Practice | 2014

Adherence to Growth Hormone Therapy: Results of a Multicenter Study

Banu Kucukemre Aydin; Zehra Aycan; Zeynep Siklar; Merih Berberoglu; Gönül Öcal; Semra Çetinkaya; Baş Vn; Kendirci Hn; Ergun Çetinkaya; Sukran Darcan; Damla Goksen; Olcay Evliyaoglu; Sükür M; Firdevs Bas; Feyza Darendeliler

OBJECTIVE To evaluate the adherence to growth hormone (GH) therapy and identify the influencing factors and outcomes in children. METHODS A total of 217 GH-naïve patients in 6 pediatric endocrinology clinics were enrolled in the study. Structured questionnaires were filled out and patients were evaluated at the initiation and 3rd, 6th, and 12th months of therapy. Patients were categorized into 4 adherence segments based on percentage of doses omitted at each evaluation period, classified as excellent if 0%, good if 5%, fair if 5 to 10%, and poor if > 10%. RESULTS There was a decrement in adherence to GH therapy during the study period (P = .006). Patients who showed excellent and good adherence to therapy had better growth velocity and growth velocity standard deviation scores (SDSs) (P = .014 and P = .015, respectively). A negative correlation between growth velocity SDS and number of missed injections was also observed (r = -.412; P = .007). A positive correlation between delta insulin-like growth factor-1 (IGF-1) SDS and growth velocity was demonstrated (r = .239; P = .042). IGF-1 levels were significantly higher in patients who showed excellent and good adherence to therapy (P = .01). Adherence was better in boys than in girls (P = .035), but adherence rates were not associated with age, cause of GH treatment, socioeconomic status, person who administered the injections, type of injection device, or GH product. CONCLUSION Poor adherence to GH therapy was common in our group of patients and was one of the factors underlying suboptimal growth during therapy. Before considering other problems that can affect growth, clinicians should confirm good adherence to therapy.


Journal of Pediatric Endocrinology and Metabolism | 2008

Identification of frequency and distribution of the nine most frequent mutations among patients with 21-hydroxylase deficiency in Turkey.

Sadeghi F; Yurur-Kutlay N; Merih Berberoglu; Ergun Çetinkaya; Zehra Aycan; Cengiz Kara; Ilgin Ruhi H; Gönül Öcal; Zeynep Siklar; Atilla Halil Elhan; Ajlan Tükün

UNLABELLED Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders mainly due to defects in the steroid 21-hydroxylase (CYP21A2) gene. METHODS To determine the mutational spectrum in the Turkish population, the CYP21A2 active gene was analyzed in 100 unrelated patients with the classical form of 21-hydroxylase deficiency using PCR and RFLP. RESULTS Mutations were detected in 78 patients: 64 patients were homozygous for one mutation, seven patients were compound heterozygous with different mutations on each chromosome, two patients were homozygous for two different mutations, five patients were heterozygous, and 22 patients harbored none of the tested mutations. The most frequent mutation was IVS2-13A/C (28.5%), followed by large gene deletion (17%), Q318X (11.5%), I172N (4%), V281L (3.5%), R356W (3.5%), 8-bp (3%), complex alleles (2%), P30L (1%) and E6 cluster (1%). CONCLUSION The distribution of mutation frequencies in our study was slightly different from those previously reported in Turkey and in other parts of the world.


Journal of Clinical Research in Pediatric Endocrinology | 2010

Celiac disease and autoimmune thyroid disease in children with type 1 diabetes mellitus: clinical and HLA-genotyping results.

Ayça Törel Ergür; Gönül Öcal; Merih Berberoglu; Pelin Adiyaman; Zeynep Siklar; Zehra Aycan; Olcay Evliyaoglu; Aydan Kansu; Girgin N; Arzu Ensari

Objective: Increased prevalence of celiac disease (CD) and autoimmune thyroid disorders (ATD) in patients with Type 1 diabetes mellitus (T1D) has been widely reported. Such an association may lead to adverse effects on the growth, bone metabolism and fertility, and response to therapy may become difficult. The aim of this study was to evaluate the clinical findings and HLA typing results in patients with T1D associated with CD or ATD. Methods: The association of CD and ATD was evaluated in 38 children with T1D aged 1.5−16.8 years who had been followed for 48.3±28 months. Diagnosis of CD was based on positivity for serum endomysial IgA antibody and histopathological findings of intestinal biopsy specimens. Thyroid autoimmunity was assessed by antithyroglobulin and antithyroid peroxidase antibodies and with diagnostic ultrasonographic findings. Results: ATD was detected in 31.5%, and CD−in 7.8% of T1D patients. Subjects with CD showed either no symptoms or suggestive problems such as short stature, hepatosteatosis, pubertal delay and difficulties in the control of diabetes. Patients with ATD had no clinical symptoms. DQ8 was the most prominent finding in CD. Conclusions: It is essential that patients with T1D, regardless of presence or absence of symptoms, should be investigated for CD and ATD. Conflict of interest:None declared.

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Semra Çetinkaya

Boston Children's Hospital

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Ergun Çetinkaya

Boston Children's Hospital

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Veysel Nijat Baş

Yıldırım Beyazıt University

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Elif Sagsak

Boston Children's Hospital

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