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Dive into the research topics where Nilgun Guvener Demirag is active.

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Featured researches published by Nilgun Guvener Demirag.


Clinical Endocrinology | 2010

Effects of rosiglitazone on bone mineral density and remodelling parameters in Postmenopausal diabetic women: a 2-year follow-up study.

Zehra Berberoglu; Ayse Canan Yazici; Nilgun Guvener Demirag

Objective  To evaluate the effect of rosiglitazone on bone metabolism and bone density.


Clinical Endocrinology | 2007

The analgesic efficacy of lidocaine/prilocaine (EMLA) cream during fine‐needle aspiration biopsy of thyroid nodules

Alptekin Gursoy; Derun Taner Ertugrul; Mustafa Sahin; Neslihan Bascil Tutuncu; Asli Nar Demirer; Nilgun Guvener Demirag

Objective  Pain is one of the few drawbacks of fine‐needle aspiration biopsy (FNAB) in patients with nodular thyroid disease (NTD). Lidocaine/prilocaine cream, an eutectic mixture of local anaesthetics (EMLA), is a frequently used topical anaesthetic. Despite its well‐documented efficacy for the relief of pain associated with other cutaneous procedures that involve needle insertion, the analgesic role of EMLA has not been previously reported in patients with NTD who are undergoing FNAB. The aim of this study was to determine the analgesic efficacy of EMLA for FNAB‐associated pain in patients with NTD.


Medical Principles and Practice | 2008

Subclinical Hypothyroidism Is Characterized by Increased QT Interval Dispersion among Women

Okan Bakiner; Melek Eda Ertorer; Filiz Eksi Haydardedeoglu; Emre Bozkirli; Neslihan Bascil Tutuncu; Nilgun Guvener Demirag

Objective: Increased QT interval dispersion (QTd) is an electrocardiographic parameter shown to be associated with malignant ventricular arrhythmias and sudden death, and QT dispersion corrected for heart rate (QTc) has emerged as a potentially important predictor of cardiac death. Increased QTd has been detected to be directly related to thyroid-stimulating hormone (TSH) levels in overt hypothyroidism, however not much is known about subclinical hypothyroidism (SH). This study was conducted to investigate the QTc in SH and determine the changes following normalization of TSH levels with L-thyroxine. Subjects and Methods: Fifty-eight women with naive SH due to Hashimoto’s thyroiditis, mean age 39.37 ± 10.43 years, and 54 age-, sex- and weight-matched controls with normal TSH were included after exclusion of any factor that might interfere with cardiac conductibility. Electrocardiographic measurements were performed with a magnifier and Bazett’s formula was used to calculate QTc. The patients were separated into two groups regarding basal TSH levels (subgroup A: 5 > TSH > 10 mIU/l, n = 36; subgroup B: TSH > 10 mIU/l, n = 22). L-Thyroxine 1–2 µg/kg/day was administered to subgroup B. Results: Mean QTc interval of the study group was significantly longer than that of the control group (100 ± 30 vs. 76 ± 30 ms, p = 0.000). It was also longer in subgroup A (5 > TSH > 10 mIU/l, n = 36) and subgroup B (p = 0.001, p = 0.000, respectively). In subgroup B, following normalization of serum TSH, mean post-treatment QTc measurement was similar to that of the control group (75 ± 40 vs. 76 ± 30 ms, p > 0.05). Conclusion: We detected prolonged QTc among SH cases. Prolongation remained significant for the whole group as well as the two subgroups. The differences in QTc were corrected when TSH levels of >10 mIU/l returned to normal.


Journal of The National Medical Association | 2008

Evaluation of brain natriuretic peptide levels in hyperthyroidism and hypothyroidism.

Derun Taner Ertugrul; Alptekin Gursoy; Mustafa Sahin; Asli Dogruk Unal; Baris Onder Pamuk; Zehra Berberoglu; Semra Ayturk; Neslihan Bascil Tutuncu; Nilgun Guvener Demirag

BACKGROUND Brain natriuretic peptide (BNP) is secreted from the ventricular myocardium in response to volume expansion and pressure overload. Serum BNP levels are also affected by thyroid function status, which was mostly related to a direct stimulatory effect of thyroid hormones on the secretion of BNP. Although the diagnostic value of BNP in heart failure is undisputed, its value in the presence of the thyroid dysfunction has been recently questioned. The aim of this study was to evaluate the influence of thyroid dysfunction on BNP levels. METHODS Evaluation of 18 overt and 47 subclinical hyperthyroid patients together with 39 subclinical and 13 overt hypothyroid patients was carried out in a cross-sectional study. Thirty-three age-, sex- and body mass index (BMI)-matched control subjects were also included. RESULTS BNP levels were more than five times higher in hyperthyroid than euthyroid control subjects (P < 0.001). BNP levels were also higher in subclinical hyperthyroidism than euthyroid control subjects (P = 0.09). Correlation analysis revealed that free T4 and free T3 concentrations were associated with high serum BNP levels. The BNP level in patients with subclinical or overt hypothyroidism was similar to that of the controls. CONCLUSION The current study provides additional insight into the diagnostic value of BNP in the presence of coexistent thyroid dysfunction and demonstrates important independent effects of thyroid hormones upon BNP plasma concentrations.


Clinical Endocrinology | 2010

ORIGINAL ARTICLE: Effects of rosiglitazone on bone mineral density and remodelling parameters in Postmenopausal diabetic women: a 2-year follow-up study

Zehra Berberoglu; Ayse Canan Yazici; Nilgun Guvener Demirag

Objective  To evaluate the effect of rosiglitazone on bone metabolism and bone density.


Endocrine | 2006

Postprandial lipemia as a risk factor for cardiovascular disease in patients with hypothyroidism

Nedret Tanaci; Derun Taner Ertugrul; Mustafa Sahin; Muammer Yucel; Irem Olcay; Nilgun Guvener Demirag; Alptekin Gursoy

Postprandial lipoprotein metabolism is suggested to play a role in the pathogenesis of atherosclerosis. In this study, we investigated postprandial lipemia and its relationship to cardiovascular risk factors in patients with overt and subclinical hypothyroidism. Twentynine female patients with TSH levels greater than 5 μIU/mL and 12 euthyroid control female subjects were included in the study. Fifteen patients had subclinical hypothyroidism and 14 had overt hypothyroidism. All subjects underwent an oral lipid tolerance test. If triglyceride levels increased by 80% or more, subjects were considered postprandial lipemia positive. Control, overt hypothyroid, and subclinical hypothyroid groups were not statistically different with respect to anthropometric measurements, fasting blood C-reactive protein, uric acid, homocysteine, glucose, insulin, lipoprotein (a), apolipoprotein B levels, and homeostasis model assessment index. Fasting triglyceride levels correlated positively with TSH levels. Postprandial lipemia frequency was higher in overt hypothyroid subjects than in the control group. The subclinical hypothyroid group did not differ from the hypothyroid group with respect to postprandial lipemia frequency. In subjects with TSH levels higher than 5 μIU/mL, PPL risk was increased sevenfold. The results of this study show that postprandial triglyceride metabolism is affected in hypothyroidism.


Journal of The National Medical Association | 2008

Radioactive Iodine in the Treatment of Type-2 Amiodarone-Induced Thyrotoxicosis

Gursoy Alptekin; Neslihan Bascil Tutuncu; Cuneyd Anil; Asli Nar Demirer; Nilgun Guvener Demirag; Arzu Gençoğlu

OBJECTIVE Amiodarone-induced thyrotoxicosis (AIT) is usually classified into two types: type 1, in which a high iodine content triggers the autonomous production of thyroid hormone; and type 2, in which destructive thyroiditis causes the release of preformed thyroid hormone. AIT is a difficult management problem that sometimes requires ablative thyroid therapy. The use of radioactive iodine (RAI) therapy in patients with type-1 AIT who had a 24-hour radioactive iodine uptake (RAIU) value of >10% has been previously reported. Despite its documented efficacy at usual doses (10-30 mCi) in patients with type-1 AIT, the efficacy of RAI in those with type-2 AIT has never been questioned, because type-2 patients usually have low RAIU. We thought that high adjusted-dose RAI might be an attractive alternative to thyroid gland ablation in patients with type-2 AIT. PATIENTS AND METHODS Four patients with type-2 AIT who required thyroid ablation were included in the study. These individuals were either poor candidates for surgery or had refused surgery. The size of the thyroid gland in all subjects was within normal limits, and each thyroid was characterized by a homogenous echotexture on ultrasonography, the absence of vascularity on Doppler sonography, a low (<4%) 24-hour RAIU value and the absence of thyroid autoantibodies-all of which are characteristic of type-2 AIT. RESULTS The patients were initially treated with thionamides and glucocorticoids. All patients except one achieved euthyroidism before RAI therapy. All four patients received one dose of RAI (range 29-80 mCi) and followed up for 12 months. No exacerbation of thyrotoxicosis was noted after RAI therapy. Hypothyroidism (in three patients) or euthyroidism (in one patient) was achieved in first six months. CONCLUSIONS In patients with type-2 AIT, RAI treatment may be the therapy of choice for thyroid gland ablation.


Pakistan Journal of Medical Sciences | 2012

Frequency of Vitamin D deficiency in pregnant diabetics at Baskent University Hospital, Istanbul.

Hulya Parildar; Asli Dogruk Unal; Guldeniz Aksan Desteli; Ozlem Cigerli; Nilgun Guvener Demirag

Objective: To find out the frequency of vitamin D deficiency and its relation with glucose parameters and the incidence of gestational diabetes (GDM). Methodology: Gestational diabetes was diagnosed with 75 gram oral glucose tolerance test. Forty-four pregnant women diagnosed with GDM and 78 non-GDM pregnant women were enrolled as case and control group, respectively in this descriptive study. Vitamin D status was classified as deficiency at ≤20 ng/ml for serum 25(OH)D concentrations. Results: The mean ages were 33.4±5.2 (18-44) years and 29.7±4.1 (21-39) years, mean BMI was 30.6±5.9 kg/m² (19.5-46.1) and 25.9±4.4 kg/m2 (16.5-38) in case and control groups, respectively. The frequency of GDM was found 9.38%. The mean serum vitamin D levels in GDM group were significantly lower than in non-GDM subjects (p=0.07). A total of 56.8% of GDM patients were compared with 35.8% of control group which had Vitamin D deficiency and the difference was significant (p= 0.02). There was no significant association between vitamin D levels and fasting glucose, insulin and HbA1c. Vitamin D levels were inversely correlated with clothing style, parathyroid hormone levels, dental problems and muscle cramps. Conclusions: The association of maternal Vitamin D status with the markers of glucose metabolism in pregnancy needs prospective studies.


Diabetes Research and Clinical Practice | 2010

Newly diagnosed hyperglycemia and stress hyperglycemia in a coronary intensive care unit

Melek Eda Ertorer; Filiz Eksi Haydardedeoglu; T. Erol; Inan Anaforoglu; S. Binici; Neslihan Bascil Tutuncu; A. Sezgin; Nilgun Guvener Demirag

AIMS To determine prevalence of newly diagnosed hyperglycemia (NDH) among patients with acute coronary disease, inquire relationship of stress hyperglycemia (SH) with functional outcomes. METHODS Admission (APG) and first morning fasting plasma glucose (FPG) measurements were obtained, capillary glucose measurements (CGM) every 6-h within first day were performed-Group 1: Normoglycemics. Group 2: NDH cases: No known diabetes, APG>200mg/dl and/or FPG>126 and/or any of CGM>200. Group 2a: unrecognized glycemic disorder, HbA1c>6.0%. Group 2b: stress hyperglycemia, HbA1c<6.0%. Group 3: Recognized diabetes. Duration of ICU stays, APACHE-II scores were recorded. Logistic regression analysis was performed using ICU stay as dependent variable and age, groups, co-morbidities, problems in hospital, APACHE-II scores, CGMs were used as independent risk factors. RESULTS There were 255 (51.6%) in Group 1, 82 (16.6%) in Group 2; 37 (7.5%) cases in Group 2a, 45 (9.1%) in Group 2b and 157 (31.8%) in Group 3. Group 2b spent longer time in ICU, had higher APACHE-II scores (p=0.0001, p=0.0001). Regression analysis demonstrated SH as an independent risk factor for duration of ICU stay (OR: 2.8, 95% CI: 1.3-6.2). CONCLUSIONS Hyperglycemia was present in 48.4%; 16.6% had NDH, 9.1% had SH. Poor functional conditions of SH cases pointed that they need to be considered carefully.


Medical Principles and Practice | 2009

49,XXXXY syndrome with autoimmune diabetes and ocular manifestations.

Baris Onder Pamuk; Ayse Nur Torun; Mustafa Kulaksizoglu; Cengiz Algan; Derun Taner Ertugrul; Zerrin Yilmaz; Neslihan Bascil Tutuncu; Nilgun Guvener Demirag

Objective: We report a rare case of 49,XXXXY syndrome with autoimmune diabetes (requiring insulin therapy), bilateral cataracts and unilateral glaucoma. Clinical Presentation and Intervention: A 25-year-old man with mental retardation presented with multiple skeletal abnormalities, polyuria and polydipsia. He had high glucose concentrations, without ketonuria, and hypergonadotropic hypogonadism. Ophthalmic examination revealed a polar cataract in both eyes and increased intraocular pressure in the left eye. The anti-islet cell antibody test was positive, and anti-glutamic acid decarboxylase autoantibody levels were elevated. Karyotype analysis revealed 49,XXXXY. Intensive insulin therapy and testosterone replacements were started. Conclusion: The autoimmune nature of diabetes that we observed in our patient seems to be predisposed by hypogonadism. Cataract and glaucoma in this case seem to be the result of diabetes, and an association of these ocular manifestations with the syndrome 49,XXXXY seems unlikely.

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Mustafa Sahin

Boston Children's Hospital

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