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Featured researches published by Funda Ustun.


Annals of Nuclear Medicine | 2002

Salivary function in patients with chronic renal failure undergoing hemodialysis

Meryem Kaya; Tevfik Fikret Cermik; Funda Ustun; Saniye Şen; Şakir Berkarda

Purpose: The aim of this study was to evaluate the changes in salivary gland function in patients with chronic renal failure (CRF) undergoing hemodialysis.Methods: The group consisted of 23 patients with CRF (13 female, 10 male; mean age: 40±13 yr) and 14 healthy control subjects (mean age: 40±13 yr). All underwent dynamic salivary gland scintigraphy with gustatory stimulation. After intravenous administration of99mTc pertechnetate, first, perfusion images at 2 seconds per frame were acquired for 1 minute, then dynamic images at 1 minute per frame were acquired for 45 minutes. At 30 minutes after injection, 10 ml lemon juice was given for 15 minutes as a gustatory stimulus. We obtained time-activity curves derived from regions of interest centered over the four major salivary glands. The following functional indices were calculated for each gland: the time of maximum radioactivity (Tmax) for the prestimulated period, the time of minimum radioactivity (Tmin), as an indicator of velocity of secretion after stimulation, and the Lem E5% value as an indicator of the secretion function.Results: When the patients with CRF undergoing hemodialysis were compared to the controls, there were statistically significant differences in Tmax, Tmin and Lem E5% values for bilateral parotid glands, and Tmin values for bilateral submandibular glands (p<0.05), there were no statistically significant differences in Tmax and Lem E5% values for bilateral submandibular glands. There were also significant differences in Tmax and Lem E5% values for bilateral parotid glands between mild oral problems and severe oral problems in patients with CRF (undergoing hemodialysis).Conclusion: In this study, prolonged Tmax and Tmin values, and decreased Lem E5% values for parotid glands and prolonged Tmin values for submandibular glands on salivary scintigraphy pointed out decreased parenchymatous and excretory function in patients with CRF undergoing hemodialysis.


Brain & Development | 2002

The relationship between 99mTc-HMPAO brain SPECT and the scores of real life rating scale in autistic children

Meryem Kaya; Serap Karasalihoğlu; Funda Ustun; Aziz Gültekin; Tevfik Fikret Cermik; Yeşim Fazlıoğlu; Mevlut Ture; Ömer N. Yiğitbaşı; Şakir Berkarda

Childhood autism is a developmental disability of unknown origin with probable multiple etiologies. The purpose of this study was to compare the changes of regional cerebral blood flow (rCBF) in autistic and non-autistic controls, and to determine the relationship between rCBF on 99mTc-hexamethylpropylene amine oxime (HMPAO) brain SPECT and the scores of the Ritvo-Freeman Real Life Rating Scale (RLRS), IQ levels, and age of autistic children. Eighteen autistic children (four girls, 14 boys; mean age: 6.13 +/- 1.99 years) and 11 non-autistic controls (five girls, six boys, mean age: 6.5 +/- 3.39 years) were examined using 99mTc-HMPAO brain SPECT. All the children satisfying DSM-IV criteria for autistic disorder were taken into evaluation, and scored by the Ritvo-Freeman RLRS. IQ levels of these children were determined by Goodenough IQ test. Six cortical regions of interest (ROIs; frontal (F), parietal (P), frontotemporal (FT), temporal (T), temporo-occipital (TO), and occipital (O)) were obtained on transaxial slices for count data acquisition. The ratio of average counts in each ROI to whole-slice counts for the autistic children was correlated with the scores of Ritvo-Freeman RLRS. Hypoperfusion in rCBF in autistic children compared with the control group were identified in bilateral F, FT, T, and TO regions. We found no relationship between rCBF on 99mTc-HMPAO brain SPECT and the scores of the Ritvo-Freeman RLRS. There was a relationship between bilateral F regions perfusion on 99mTc-HMPAO brain SPECT and the age of autistic children. There was also a negative correlation between IQ levels and the scores of sensory responses, social relationship to people, and sensory-motor responses. Our results suggest that 99mTc-HMPAO brain SPECT is helpful to locate the perfusion abnormalities but no correlation is found between rCBF on 99mTc-HMPAO brain SPECT and the scores of Ritvo-Freeman RLRS.


Annals of Nuclear Medicine | 2005

The incidence of recurrence and hypothyroidism after radioiodine treatment in patients with hyperthyroidism in Trakya, a mild iodine deficiency area, during the period 1991–2003

Funda Ustun; Mahmut Yüksel; Gülay Dukmus-Altun; Meryem Kaya; Tevfik Fikret Çermjk; Ali Sarikaya; Sakir Berkarda

ObjectiveThe purpose of this retrospective study was to evaluate the incidence of recurrence and the success of radioiodine treatment (RIT) in the Trakya region of Turkey, an area with mild iodine deficiency, and to compare the effect of dose regimen selection (fixed (FD) or calculated dose (CD)) on treatment success.Material and MethodsThe study sample included 148 patients (40 male, median age 50) treated with radioiodine between the years 1991-2003. Patients were categorized into three diagnostic groups: Graves’ disease (GD) (n = 65), solitary toxic adenoma (TA) (n = 29), and toxic multinodular hyperthyroidism (TMH) (n = 54), and each divided into two subgroups according to treatment method; the first group was treated with a FD of 370 MBq (10 mCi), and the second with CD.ResultsThe largest group was GD (44%), followed by TMH (36%). Median duration of follow-up was 28 months (range 6-147). FD was given to 52.7% of all patients and CD was given to 47.3%. There was a partial difference in the dose regimen between all groups, but did not reach statistically significant levels (FD vs. CD: 65%–35%; 38%–62%; 46%–54%; GD, TA, TMH respectively, p > 0.05). Total cure rate in FD and CD was 46 (59%) and 37 (52.9%), respectively. The rates of hypothyroidism for GD, TA, and TMH groups were 28 (43.1%), 6 (20.7%) and 16 (29.6%), respectively. The incidence of hypothyroidism did not vary significantly between any groups (p > 0.05). At the end of the follow-up period, a total of 104 patients (70.3%) were treated successfully. There was no significant difference in the cure rate between any groups (p > 0.05).ConclusionsThe treatment success in all groups and subgroups did not differ significantly between FD and CD. Our lower cure rate than in previous studies may be related to iodine deficiency. Higher doses of radioiodine may be required to increase final treatment success in endemic goiter areas. If this true, dosimetry and calculated dose regimen would be required in all groups of patients instead of an FD concept. However, our findings should be verified in larger series of patients, with longer follow-up period, and urinary iodine concentration measurements.


World journal of nuclear medicine | 2017

Liver metastasis of lung cancer detected with similar uptake pattern on bone scintigraphy and fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography: What's the pathophysiologic mechanism?

Funda Ustun; Salim Aksoy; BurcuDirlik Serim; GülayDurmuş Altun

Bone scintigraphy with 99mTc diphosphonates may exhibit extraosseous lesions in addition to metastatic lesions. Multiple factors can affect extraosseous 99mTc methylene diphosphonate (MDP) uptake. Similar uptake pattern of 99mTc MDP and fluorine-18 fluorodeoxyglucose (18F FDG) in hepatic metastasis was not already notified. In our case, initial tumor necrosis and subsequent intracellular calcification resulted in similar 99mTc MDP and 18F FDG accumulation in the metastatic area.


Polish Journal of Pathology | 2016

Histological perspective on the effects of tumor-associated macrophages in the tumor microenvironment surrounding papillary thyroid carcinoma

Nuray Can; Semra Ayturk; Mehmet Celik; Yavuz Atakan Sezer; Filiz Ozyilmaz; Ebru Tastekin; Necdet Sut; Funda Ustun; Buket Yilmaz Bulbul; Fulya Oz Puyan; Sibel Guldiken

Tumor-associated macrophages (TAMs) are one of the most noticeable elements of the tumor microenvironment. The present study investigated the relationships between the density of CD163 immunolabeled M2-like TAMs with other histological properties of the tumor microenvironment and clinipathological features in 90 patients with papillary thyroid carcinomas (PTC). The percentage of TAMs was higher in tumors with significant lymphocytic tumor response (p = 0.020), in tumors with a significant degree of stromal tumor response (p = 0.014), those with infiltrative tumor borders (p = 0.029), in conventional variant papillary carcinoma (p = 0.032), and in patients with autoantibodies for thyroid peroxidase (p = 0.014). The tumors associated with lymphocytic thyroiditis had lower numbers of TAMs (p = 0.027). In conclusion, for the first time, the present study attempts to establish a full assessment of interactions of CD163 expressing M2-like TAMs with the triad of primary tumor- tumor microenvironment- tumor behavior and above all, with markers of autoimmunity. Thus, these alternatively polarized macrophages may act in tumor progression and dissemination according to their various products, which may be ordered by tumor cells or neighboring immune cells. The molecular studies may reveal their roles in various tumors and may improve the therapy strategies targeting TAMs in various malignant tumors, including PTCs.


International Journal of Pediatric Otorhinolaryngology | 2009

A new imaging modality in detection of caustic oesophageal injury: Technetium-99m pyrophosphate scintigraphy

Burhan Aksu; Gulay Durmus-Altun; Funda Ustun; Nese Torun; Mehmet Kanter; Hasan Umit; Nejdet Sut

OBJECTIVES Early oesophagoscopy is usually recommended in children after caustic ingestion to assess the severity of the initial digestive lesions. An oesophagoscopic procedure in children always demands to be performed under sedation and bears a certain risk of iatrogenic injury. The purpose of the study is to determine the value and sensitivity of Tc-99m pyrophosphate (99mTc-PYP) scintigraphy for the detection of caustic oesophageal injury. METHODS The caustic oesophageal burns were created with 25% NaOH in an experimental rat model. Seventeen rats were divided into two groups. The BURN group (n=9) included caustic oesophageal burning rats. Non-BURN group (n=8) included sham-operated rats. All animals underwent 99mTc-PYP scintigraphy 72 h after the burning experiment. Anterior static and single-photon emission computed tomography images were obtained using a low-energy all-purpose collimator, 2.55 zoom factor, 3h after intravenous injection of 10 mCi 99mTc-PYP. After the imaging, all the oesophagi were explored for external determination of the injury sites and macroautoradiographic scintigraphy as well. Rectangular region of interest were placed in the visually determined lesion of oesophagus (O) as well as non-lesion area (N), and an ON ratio was created. The severity and extension of oesophageal burn were assessed 3 days after burning by histopathologic evaluation. The injuries were graded according to the ulcer depth, ulcer width, thrombus formation, and the development of perivascular fibrinoid necrosis. RESULTS The oesophageal burning areas were demonstrated by visual evaluation of the Tc-99m PYP scintigraphy on all animals. The mean ON ratio of 99mTc-PYP was 21.61+/-7.01 in the BURN group and in the non-BURN group, was 2.25+/-0.24 (p<0.001). The best cut-off point of the ON ratio for caustic oesophageal injury was 5.45, with sensitivity and specificity of 100%. PYP scan findings were also confirmed by histological evidence of ulcer depth, ulcer width, thrombus formation, and perivascular fibrinoid necrosis in the same areas. CONCLUSIONS The caustic oesophageal injuries have been demonstrated by 99mTc-PYP scintigraphy in burning experiment. 99mTc-PYP scintigraphy is sensitive for detection of caustic oesophageal injury. This new imaging tool is found to be sensitive and specific for the detection of caustic oesophageal injury in the rats.


Cancer Biotherapy and Radiopharmaceuticals | 2009

Glucose-induced alteration of accumulation of organotechnetium complexes accumulation in Pgp-negative tumor-bearing mice.

Funda Ustun; Gulay Durmus-Altun; Ziya Cukur; Semsi Altaner; Sakir Berkarda

The biologic and microenvironmental factors determining (99m)Tc sestamibi (MIBI) and (99m)Tc tetrofosmin (TF) uptake in breast tumors are incompletely understood, especially in P-glycoprotein (Pgp)-negative tumors. We analyzed the influence of glucose administration on the uptake and retention of MIBI and TF in Pgp-negative tumor-bearing mice in vivo. Twenty (20) mice bearing Ehrlich ascites tumor cell (EATC) xenografts were divided into four groups: (1) MIBI, (2) MIBI+glucose, (3) TF, and (4) TF+glucose. Glucose was administered (5.0 g/kg body weight) intraperitoreally (i.p.) 1 hour before scintigraphy. There were significant differences between the E-UPR MIBI and MIBI+glucose groups (p = 0.009) and minor differences in L-UPR between these groups (p = 0.04). There was a significant inverse correlation between E-UPR of MIBI and glucose levels (r = 0.71, p = 0.02). Comparing the four groups, the highest E-UPR was obtained in the MIBI group (p = 0.006). Other parameters were not different in the MIBI and MIBI+glucose groups and in the TF and TF+glucose groups. Increased blood glucose level affected the MIBI uptake of tumor tissue, particularly for E-UPR. We suggest that these findings were due to basically decreased blood flow and secondarily decreased extracellular pH. However, glucose administration did not affect TF.


Clinical Nuclear Medicine | 2001

Extensive bone metastases in a patient with prostatic adenocarcinoma and normal serum prostate-specific antigen and prostatic acid phosphatase.

Mahmut Yüksel; Tevfik Cermik; Meryem Kaya; Ahmet Salan; Funda Ustun; Salihoglu Ys; Ömer N. Yiğitbaşı; Sakir Berkarda

A 49-year-old man was hospitalized because of severe back pain and weight loss for 2 months. Because the serum carcinoembryonic antigen (CEA) level was elevated to 37.5 ng/ml (normal, <5.2 ng/ml), gastrointestinal endoscopy was performed but no suspicious lesions were found in the gastrointestinal tract He was referred for a bone scan after computed tomography disclosed multiple destructive lesions in the lumbar spine. Tc-99m MDP bone scintigraphy showed multiple bone metastases.


Dermatologic Therapy | 2018

Recurrent Merkel cell carcinoma of the gluteal region: A case report

Görkem Türkkan; Ozgur Agdogan; Mert Saynak; Arzu C. Uygun; Funda Ustun

Merkel cell carcinoma (MCC) is a rare malignant tumor of the skin. The development of MCC on non‐sun‐exposed skin is extremely rare, with few cases reported in the literature. The present authors aimed to highlight the characteristic features and treatment options of this tumor. The present authors present a 50‐year‐old man who developed MCC on the left gluteal region (non‐sun‐exposed skin). After surgery with clear margins, adjuvant radiotherapy was given. Three months after radiotherapy, lymphatic recurrence was observed and he was treated with chemotherapy. On follow‐up, systemic metastases were found and palliative treatment was planned.


Polish Journal of Pathology | 2017

Comparison of clinicopathological features in incidental and nonincidental papillary thyroid carcinomas in 308 patients

Nuray Can; Filiz Ozyilmaz; Mehmet Celik; Atakan Sezer; Necdet Sut; Ebru Tastekin; Semra Ayturk; Funda Ustun; Buket Yilmaz Bulbul; Sibel Guldiken

Incidental papillary thyroid carcinomas (IPTCs) consist of a significant portion of increasing incidence in papillary thyroid carcinomas. This study investigated the clinicopathological features of IPTCs from different perspectives and by comparing nonincidental PTCs (NIPTCs) in patients who underwent total thyroidectomy and lymph node dissection. Basic results were as follows. IPTC was present in 27.9% of 308 patients. IPTCs were significantly accompanied by lymphocytic thyroiditis (LT), particularly, multinodular hyperplasia (MNH). IPTCs were more common in older patients (51.3 years vs. 47.2 years) and in female patients. IPTCs significantly differed from NIPTCs in terms of smaller tumour size, lymphatic vessel invasion (2.6% vs. 97.4%), extrathyroidal extension (4.3% vs. 95.7%), lymph node metastasis (3.6% vs. 96.4%), multifocality (21.2% vs. 78.8%), bilaterality (5.3% vs. 94.7%), and BRAFV600 mutation (6.7% vs. 93.3%). Older age, bilaterality, encapsulation, and radioactive iodine (RAI) were significantly more common in IPTCs > 5 mm than in those ≤ 5 mm. In conclusion, IPTCs are more commonly associated with LT and MNH. IPTCs may have a more favourable prognosis than NIPTCs, and tumour size > 5 mm may predict bilaterality and need for RAI. Nevertheless, the patient-based clinical approach in IPTCs may have benefits in the management of IPTCs.

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