Person: ÖNEŞ, TUNÇ
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ÖNEŞ
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TUNÇ
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Publication Metadata only A new silent germline mutation of the TSH receptor: Coexpression in a hyperthyroid family member with a second activating somatic mutation(MARY ANN LIEBERT, INC, 2008) GÖZÜ, HÜLYA; Gozu, Hulya Iliksu; Mueller, Sandra; Bircan, Rifat; Krohn, Knut; Ekinci, Gazenfer; Yavuzer, Dilek; Sargin, Haluk; Sargin, Mehmet; Ones, Tunc; Gezen, Cem; Orbay, Ekrem; Cirakoglu, Beyazit; Paschke, RalfBackground: Up to date, three thyroid-stimulating hormone receptor (TSHR) germline variants have been reported for which no functional consequences have been detected by in vitro characterizations. However, familial nonautoimmune hyperthyroidism and hot nodules are clearly associated with constitutively activating TSHR germline mutations. We describe a family with a new TSHR germline mutation that is associated with euthyroidism in 13 family members and hyperthyroidism in 1 family member. Methods: Mutation analysis of the TSHR gene was performed by denaturing gradient gel electrophoresis. TSHR constructs were characterized by determination of cell surface expression, 3'-5'- cyclic adenosine monophosphate ( cAMP) accumulation, and constitutive cAMP activity. Results: A novel TSHR germline mutation ( N372T) was found in a man who presented with thyrotoxicosis. The mutation was also detected in 13 family members, all of whom were euthyroid. Interestingly, an additional constitutively active somatic mutation ( S281N) was identified on the second parental TSHR allele of the hyperthyroid index patient. Linear regression analysis showed a lack of constitutive activity for N372T. Moreover, coexpression studies of N372T with S281N did not reveal any evidence for a functional influence of N372T on the constitutively active mutation ( CAM). Conclusions: N372T is unlikely to cause altered thyroid function. This is consistent with the finding that only the index patient with the additional somatic mutation S281N was hyperthyroid.Publication Metadata only Simple provocative maneuvers in renal transplant scintigraphy for detecting urine leak(SPRINGER, 2007) DEDE, FUAT; Dede, Fuat; Ones, Tunc; Caliskan, Billur; Civen, Huseyin; Erdil, Tanju Y.; Inanir, Sabahat; Tuglular, Zubeyde S.; Yegen, Cumhur; Akoglu, Emel; Turoglu, Halil T.Urine leak in the early postoperative period following renal transplantation is a serious complication requiring early identification and aggressive intervention, which significantly reduces the morbidity and mortality. Renal transplant scintigraphy is a noninvasive method to evaluate the perfusion and function of a transplanted kidney and urinary drainage including urine leak. Here, we reported two cases in which the standard transplant renogram failed to demonstrate urine leak. The cases were referred for a diethylenetriaminepentaacetic acid renogram following the transplantation to evaluate the cause of symptoms or elevated serum creatinine level. In both the cases, urine leak was successfully detected following simple maneuvers such as diuretic administration or Foley catheter irrigation. Renal transplant scintigraphy is an effective and safe technique and the use of these simple maneuvers can enhance the diagnostic sensitivity of the transplant renogram in the detection of urine leak.Publication Open Access Orlistat accelerates gastric emptying and attenuates GIP release in healthy subjects(AMER PHYSIOLOGICAL SOC, 2009-03) HAKLAR, GONCAGÜL; Enc, Feruze Yilmaz; Oenes, Tunc; Akin, H. Levent; Dede, Fuat; Turoglu, H. Turgut; Uelfer, Goerzde; Bekiroglu, Nural; Haklar, Goncaguel; Rehfeld, Jens F.; Holst, Jens J.; Ulusoy, Nefise B.; Imeryuez, NeseEnc, FY, Ones,T, Akin HL, Dede F, Turoglu HT, Ulfer G, Bekiroglu N, Haklar G, Rehfeld JF, Holst JJ, Ulusoy NB, Imeryuz N. Orlistat accelerates gastric emptying and attenuates GIP release in healthy subjects. Am J Physiol Gastrointest Liver Physiol 296: G482-G489, 2009. First published December 24, 2008; doi:10.1152/ajpgi.90209.2008.-Orlistat, an inhibitor of digestive lipases, is widely used for the treatment of obesity. Previous reports on the effect of orally ingested orlistat together with a meal on gastric emptying and secretion of gut peptides that modulate postprandial responses are controversial. We investigated the effect of ingested orlistat on gastric emptying and plasma responses of gut peptides in response to a solid mixed meal with a moderate energy load. In healthy subjects, gastric emptying was determined using scintigraphy and studies were performed without and with 120 mg of orlistat in pellet form in random order. Orlistat shortened t lag and t half and decreased the area under the gastric emptying curve. Orlistat significantly attenuated the secretion of glucose-dependent insulinotropic polypeptide (GIP) but did not alter the plasma responses of cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), pancreatic polypeptide (PP), and insulin. There was no peptide YY (PYY) response. Area under the curve of gastric emptying was positively correlated with integrated secretion of GIP (r = 0.786) in orlistat and was negatively correlated with integrated plasma response of GLP-1 (r = -0.75) in control experiments, implying that inhibition of fat absorption modifies determinants of gastric emptying of a meal. Orlistat administered similar to its use in obesity treatment accelerates gastric emptying of a solid mixed meal with a moderate energy load and profoundly attenuates release of GIP without appreciably altering plasma responses of CCK, GLP-1, and PP. Since GIP is being implemented in the development of obesity, its role in weight control attained by orlistat awaits further investigation.Publication Metadata only The clinical utility of 99(m)Tc-HMPAO SPECT in Fahr's disease(SPRINGER, 2008) GÜNAL, DİLEK; Ones, Tunc; Dede, Fuat; Gunal, Dilek; Ekinci, Gazanfer; Memis, Hatice; Erdil, Tanju Y.; Inanir, Sabahat; Turoglu, Halil T.Fahr's disease is a rare neurodegenerative syndrome, characterized by massive symmetrical intracerebral calcifications of the basal ganglia, dentate nuclei of the cerebellum, and the adjacent parenchyma. Computerized tomography (CT) is considerably more sensitive to detect these intracranial calcifications than other imaging modalities. The clinical, CT scan, and 99(m)Tc-D,L-hexamethylpropylene amine oxime (99(m)Tc-HMPAO) brain perfusion single-photon emission computerized tomography (SPECT) findings in a 42-year-old woman with Fahr's disease are reported, and the clinical utility of 99(m)Tc-HMPAO SPECT findings in Fahr's disease is discussed in this article. In conclusion, 99(m)Tc-HMPAO brain perfusion SPECT seems to be useful in the clinical approach to Fahr's disease, and may provide more specific and clinically relevant information when compared with anatomical imaging.Publication Metadata only False positivity of FDG-PET/CT in a child with Hodgkin disease(WILEY, 2008) ÖNEŞ, TUNÇ; Beker, Dildar Bahar; Berrak, Su Gulsun; Canpolat, Cengiz; Tugtepe, Halil; Ones, Tunc; Tecimer, TulayRole of Positron Emission Tomography (PET) with F-18-2-fluoro-2-deoxy-D-glucose (FDG) in staging of Hodgkin disease is well established despite several controversies. We report a Stage III Hodgkin lymphoma patient with false positive FDG-PET/CT results. Seven-year-old male with Hodgkin lymphoma was in remission at end of chemotherapy. At third and fourth months of postchemotherapy follow-up, increased gallium uptake and positive FDG-PET/CT revealed lymphoid hyperplasia. He has been followed for 21 months without any evidence of disease. Despite its documented benefit, we believe that results of FDG-PET/CT should be interpreted with great caution in order to avoid unnecessary interventions.Publication Metadata only Does a Leu 512 Arg thyrotropin receptor mutation cause an autonomously functioning papillary carcinoma?(MARY ANN LIEBERT INC, 2004) GÖZÜ, HÜLYA; Gozu, H; Avsar, M; Bircan, R; Sahin, S; Ahiskanali, R; Gulluoglu, B; Deyneli, O; Ones, T; Narin, Y; Akalin, S; Cirakoglu, BIn the last decade, studies were first done to determine the frequency of G(s)alpha and later thyrotropin receptor (TSHR) mutations in benign autonomously functioning thyroid nodules (AFTN). Different frequencies ranging from 0% to 38% for G(S)p mutations and from 20% to 86% for TSHR mutations were found. There were only some limited case reports related to TSHR genetic alterations in malignant AFTN. Their role in autonomously functioning thyroid carcinomas is not well established. We present a patient who had thyroidectomy for toxic multinodular goiter and a papillary carcinoma was demonstrated histopathologically. Genomic DNA was isolated from two solid areas in the hot nodule and peripheral leukocytes of the patient. After amplifying the related regions, TSHR and G(S)alpha genes were analyzed by single-strand conformation polymorphism (SSCP) analysis. The precise localization of the mutations was identified by automatic DNA sequence analysis. An activating mutation of the TSHR gene (Leu 512 Arg) was found in the autonomously functioning papillary carcinoma. It is believed that this mutation causes constitutive activation of the cyclic adenosine monophosphate (CAMP) signal transduction pathway and thereby causes thyrotoxicosis and a hot thyroid nodule in an autonomously functioning papillary carcinoma.Publication Metadata only Quantitative shunt imaging in the evaluation of therapeutic surgery in a patient with pulmonary arteriovenous malformation(ELSEVIER SCIENCE INC, 2008) DEDE, FUAT; Ones, Tunc; Dede, Fuat; Erdim, Refik; Erdil, Tanju Yusuf; Inanir, Sabahat; Yuksel, Mustafa; Turoglu, Halil TurgutA case of pulmonary arteriovenous malformation (PAVM) in a 32-year-old woman who underwent successful left upper lobectomy is presented. A whole-body technetium-99m-labeled macro-aggregated albumin scan was used to demonstrate intrapulmonary right-to-left shunt, and shunt fraction was calculated as 39%. The patient underwent a follow-up scan after the operationPublication Metadata only Reproducibility of technetium-99m mercaptoacetyltriglycine clearance in patients with impaired renal function(LIPPINCOTT WILLIAMS & WILKINS, 2006) ÖNEŞ, TUNÇ; Erdil, TY; Dede, F; Tuglular, S; Sen, F; Ones, T; Farsakoglu, Z; Inanir, S; Ozener, C; Akoglu, E; Turoglu, TBackground The aim of this study was to determine the reproducibility of technetium-99m mercaptoacetyltriglycine ((99)mTc-MAG3) clearance in patients with a 99mTc-MAG3 clearance below 100 ml/min/1.73 m(2). Methods Two separate multi-sample clearance studies were performed in 16 patients at a 1 week interval. The clearances were calculated according to the open two-compartment model of Sapirstein et al., accepting the 90, 120 and 180 min samples as the last points of the biexponential curve. The clearance measurements were also performed according to the single-sample methods of Russell et al. and Bubeck using the fitted value at 44 min. Results There was no significant difference between the two clearance measurements for all five samples (P > 0.05). There was a systematic increase in clearance measurements of 8.0 +/- 2.7% from the 180 to 120 min samples and 4.8 +/- 2.0% from the 120 to 90 min samples. Both single-sample methods (Bubeck and Russell et al.) gave more divergent results than multi-sample methods. The mean and standard deviation (%) of the normalized differences between two successive tests were -3.9 +/- 12.6, -2.4 +/- 13.1, -1.9 +/- 14.9, -4.1 +/- 53.5 and -13 +/- 82.1 for 90,120 and 180min samples and the Russell et al. and Bubeck methods, respectively. Conclusion Single-sample methods give very poor reproducibility and accuracy and should not be used in patients with poor renal function. The reproducibility of Tc-99m-MAG3 clearance using the multi-sample method (90 min) in patients with impaired renal function is 12.6%, which is similar to that in patients with good renal function and that obtained with other tubular agents. Whether this level of reproducibility is satisfactory for documenting serial changes in an individual patient with a Tc-99m-MAG3 clearance below 100 ml/min/1.73 m(2) depends on the expectation of the clinician.Publication Metadata only B-type natriuretic peptide levels in patients with COPD and normal right ventricular function(SPRINGER, 2008) İNANIR, SABAHAT; Gemici, Goekwen; Erdim, Refik; Celiker, Aydin; Tokay, Sena; Ones, Tunc; Inanir, Sabahat; Oktay, AhmetIntroduction: Evidence suggests that elevated plasma levels of B-type natriuretic peptide (BNP) are found in patients with chronic obstructive pulmonary disease (COPD) and right ventricular dysfunction. We examined the effects of exercise on plasma BNP levels in patients with COPD who have normal right ventricular function. Methods: Seventeen patients with a diagnosis of COPD and normal right ventricular function demonstrated by radionuclide ventriculography, and 17 age- and sex-matched healthy subjects underwent a treadmill exercise test. Plasma BNP levels were measured sequentially before, immediately after, and 1 hour after the exercise test. Results: The mean plasma BNP +/- standard deviation levels of the COPD and control groups before exercise were 21.3 +/- 16 pg/ml and 13.4 +/- 11 pg/ml, respectively (P>0.05). Mean plasma BNP level measured immediately after exercise was 37.9 +/- 31 pg/ml in the COPD group, reflecting a statistically significant increase when compared with the initial value (P<0.05). The control group did not show any significant change in plasma BNP levels after the exercise test. Conclusion: Exercise induces an increase in plasma BNP levels in patients with COPD who do not have right ventricular dysfunction at rest. Measurement of exercise-induced BNP levels may be a useful alternative to pulmonary artery catheterisation in identifying the patients who are likely to benefit from long-term oxygen therapy.