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Öğe 18F-FDG PET/CT Imaging of Burkitt Lymphoma Presenting With Unusual Muscle Involvement(Lippincott Williams & Wilkins, 2016) Serim, Burcu Dirlik; Eren, Tuba Gurleyen; Puyan, Fulya Oz; Altun, Gulay Durmus[Abstract Not Available]Öğe 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Findings of Pancreatic Hemangiopericytoma(Medknow Publications & Media Pvt Ltd, 2017) Ustun, Funda; Aksoy, Salim; Serim, Burcu Dirlik; Altun, Gulay DurmusA 42-year-old woman with a large pancreatic tumor had undergone F-18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging. Moderate metabolic activity was detected on the head of the pancreas. The tumor was resected and it was histopathologically diagnosed as malign pancreatic hemangiopericytoma (HPC). HPC is a rare soft tissue sarcoma. The tumor is considered aggressive with high rates of local recurrence and metastasis regardless the localization. Herein, we present the imaging characteristics of HPC with F-18-FDG PET/CT.Öğe The alteration of asymmetric dimetilarginine (ADMA) levels in cardiac and gastrocnemius muscles following radioactive iodine application in guinea pigs and the effect of L-carnitine on this alteration(Taylor & Francis Ltd, 2011) Vardar, Selma Arzu; Gunduz, Ozgur; Altun, Gulay Durmus; Aydogdu, Nurettin; Karadag, Hakan; Torun, Nese; Kaya, OktayPurpose: Tissue levels of asymmetric dimetilarginine (ADMA) and symmetric dimetilarginine (SDMA) were investigated in cardiac ventricle and gastrocnemius muscles of guinea pigs treated with radioactive iodine (RAI) alone or in combination with L-carnitine (LC). Material and methods: Group 1 received no treatment (control group). Group 2 received a total dose of 30 mCi(-1)kg(-1) body weight iodine-131 alone. Group 3 received 200 mg(-1)kg(-1) of LC for 10 days alone. Group 4 received 200 mg(-1)kg(-1) of LC plus RAI therapy. Free thyroid hormones, ADMA and SDMA concentrations were measured. Results: Serum free thyroid hormone concentrations were found decreased in the RAI and LC-RAI groups after RAI application. A significant decrease in ADMA and SDMA concentration was observed in ventricle muscle following RAI application. The LC-RAI group had significantly decreased ADMA levels in ventricle muscle compared with those of the control group. Similarly, SDMA concentrations in ventricle and gastrocnemius muscles of the LC-RAI groups were significantly lower than those of the control groups. Conclusions: Our results indicated that RAI appears to exert an inhibitory effect on ADMA and SDMA levels of ventricular muscle. LC administration when given adjuvant to RAI therapy may cause a marked decrease in ADMA concentrations of both ventricular and gastrocnemius muscles.Öğe The Clinical Significance of Incidental Parotid Uptake in a PET/CT Study: A Diagnostic Algorithm(Bentham Science Publ Ltd, 2019) Ustun, Funda; Tastekin, Ebru; Tas, Abdullah; Altun, Gulay DurmusBackground: Patients diagnosed with cancer do not have sufficient clinical data for the management of incidental parotid lesions. We aimed to reveal the importance of randomized parotid lesions encountered during oncologic F-18 fluorodeoxyglucose positron emission tomography (FDG PET/CT) imaging in our clinical practice and the diagnostic algorithm of such lesions. Methods: We performed a database search of PET/CT records generated from 2009 to 2015 for parotid in reports of patients who underwent PET/CT examination for a known malignancy elsewhere, or cancer screening. Results: Incidental parotid FDG uptake on PET/CT had a prevalence of 1.1%. The incidence of parotid metastasis in our series was 36.4%, and 75% of them had malign melanoma metastasis. Of the 11 cases, 5 were of Warthin tumours, and Warthin tumours showed stronger GLUT1 expression than metastatic parotid lesions. Conclusion: In patients with malignancy elsewhere, focal involvement of FDG by the parotid gland, especially if malignant melanoma or SCC is absent, should not be considered a metastatic disease without histopathologic confirmation. If parotid disease would change the patient's treatment plan and disease stage, the parotid lesion should be evaluated by additional methods, such as fine needle aspiration biopsy.Öğe Combined effect of parathyroid hormone and strontium ranelate on bone healing in ovariectomized rats(WILEY, 2018) Goker, Funda; Ersanli, Selim; Arisan, Volkan; Cevher, Erdal; Guzel, Emine Elif; Issever, Halim; Omer, Beyhan; Altun, Gulay Durmus; Morina, Deniz; Yilmaz, Tugba Ekiz; Dervisoglu, Elmire; Del Fabbro, MassimoObjectiveParathyroid hormone (PTH) enhances bone healing. Strontium ranelate (SR) is an antiresorptive agent that increases bone formation. Reports about combined effects of PTH and SR on local bone regeneration in osteoporotic subjects are limited. We aimed at investigating the efficacy of PTH and SR for promoting new bone formation in critical-sized defects of ovariectomized rats. Materials and MethodsParathyroid hormone- and/or SR-containing poloxamer implant tablets with/without chitosan microparticles were delivered locally to calvarial defects of 90 Wistar rats. Biopsies were analyzed histologically and histomorphometrically at 4 and 8weeks of healing. ResultsHistomorphometry revealed that PTH alone promoted new bone formation at 4weeks but the efficiency declined in 8weeks. There was no positive effect of SR alone on bone formation at 4 or 8weeks. Calvarial defects treated with PTH+SR combinations showed statistically significant greater new bone formation than either treatment alone at both time intervals. Tissue responses were modest and supported the good biocompatibility of the biomaterials used. ConclusionParathyroid hormone and SR combinations can be effective for calvarial bone regeneration of ovariectomized rats. PTH plus SR may have potential use as bone graft material in orthopedic and dental surgery to enhance bone healing and osseointegration.Öğe Development of a Radiolabeled Folate-Mediated Drug Delivery System for Effective Delivery of Docetaxel(Amer Chemical Soc, 2023) Cetin, Oguz; Gungor, Burcu; Ichdef, Cigdem; Parlak, Yasemin; Bilgin, Elvan Sayit; Ustun, Funda; Altun, Gulay DurmusMany preclinical studies are carried out with the aimof developingnew formulations for the effective delivery of taxane class drugs,one of the most important anticancer drugs used clinically today.In this study, a radiolabeled folate-mediated solid lipid magneticnanoparticle (SLMNP) system was developed by loading superparamagneticiron oxide nanoparticles (MNP) and docetaxel (DTX) into the solidlipid nanoparticles as a drug delivery system that will function bothin cancer treatment and diagnosis. For this purpose, first, SLMNPwas synthesized by the hot homogenization method, and the surfaceof the particles was modified with a folate derivative to carry theparticles to tissues with folate receptors. The synthesized magneticsolid lipid nanoparticles were loaded with DTX, and then radiolabelingwas carried out with technetium-99 m (Tc-99m-DTX-SLMNP).Structural characteristics of these nanoparticles were determinedby characterization methods. According to the TEM images of MNPs,SLN, and SLMNPs, MNPs were observed between 25and 35 nm, SLNs between400 and 500 nm, and SLMNPs between 350 and 450 nm. The drug entrapmentefficiency of SLMNPs loaded with DTX was found to be 19%, and thepercentage efficiency of radiolabeling was found to be 98.0 & PLUSMN;2.0%. The biological behavior of this radiolabeled system was investigated in vitro and in vivo. Folate receptor-positiveSKOV-3 and folate receptor-negative A549 cancer cell lines were studied.The IC50 values of DTX-SLMNP in SKOV-3 and A549 cells were50.21 and 172.27 & mu;M at 48 h, respectively. Gamma camera imagingstudies of Tc-99m-DTX-SLMNP and magnetically applied Tc-99m-DTX-SLMNP compounds were performed on tumor-bearing CD-1nude mice. The uptake in the folate receptor-positive tumor regionwas higher than that in the folate receptor negative tumor region.We proposed that the drug delivery system we prepared in this studybe evaluated for preclinical studies of new drug carrier formulationsof the taxane class of anticancer drugs.Öğe The Diagnostic Contribution of SPECT/CT Imaging in the Assessment of Gastrointestinal Bleeding: Especially for Previously Operated Patients(Galenos Yayincilik, 2021) Soyluoglu, Selin; Korkmaz, Ulku; Ozdemir, Busra; Altun, Gulay DurmusObjectives: Gastrointestinal bleeding (GIB) is a life-threatening problem that requires a multidisciplinary approach for successful treatment. This study aims to emphasize the clinical contribution of single photon emission computed tomography/computed tomography (SPECT/CT) for the diagnosis of acute bleeding. Methods: All 14 patients referred to the nuclear medicine department in 3 years with suspicion of acute GIB were evaluated retrospectively. Clinical records were analyzed to assess the scintigraphic findings, emphasizing the correlative contribution of the CT portion on SPECT/CT studies. Results: Five patients were negative on dynamic and static planar images. SPECT/CT was performed in 9 patients who had positive findings on planar imaging. SPECT/CT could identify the same bleeding site originating from the anastomosis in four patients with a history of abdominal surgery. SPECT/CT confirmed bleeding from the cecum in a patient with cervical cancer. SPECT/CT showed the bleeding focus in the bladder neck of a patient with bladder cancer and the bleeding from peritoneal metastases of a patient with gastric cancer. In 1 patient, the right upper quadrant activity accumulation, which may cause false positives, was found to be the gallbladder on SPECT/CT. Delayed images showed the true bleeding focus in the cecum. In 1 patient, suspicious activity accumulation in the midline of the abdomen was found to be due to a previously unknown aortic aneurysm on SPECT/CT. Conclusion: SPECT/CT imaging is a feasible technique to facilitate image interpretation in patients with GIB. SPECT/CT imaging can guide the surgeon through more accurate localization. Therefore, for proper patient management, SPECT/CT should be applied to detect the bleeding focus, if present, especially in patients who had undergone a previous operation.Öğe Effect of Prepubertal High Intensity Training on Bone Mineral Content in Young Adult Period of Female and Male Rats(Wiley-Blackwell, 2015) Altun, Gulay Durmus; Vardar, Selma Arzu; Turan, Nesrin; Yaprak, Mevlut[Abstract Not Available]Öğe The Effects of Taurine, Melatonin and N-Acetylcystein on Cadmium Exposure Bone Changes The Surprising Effect of Taurine(Gazi Univ, Fac Med, 2020) Tastekin, Nurettin; Aydogdu, Nurettin; Altun, Gulay Durmus; Erbas, Hakan; Uzunca, Kaan; Birtane, Murat; Kaplan, MustafaBackground: Chronic environmental and occupational exposure to cadmium can result in skeletal system changes. The main objective of the present study was to investigate and compare the effects of taurine, melatonin and N-acetyl cysteine on cadmium exposure induced bone density loss. Methods: 90 adult male Sprague-Dawley rats were allocated into four main groups: Group I was the control group; Group II was the cadmium exposure group; Group 3 was cadmium exposure for 3 months + concurrent antioxidant administration group. The concept of Group 4 was cadmium exposure for 3 months + subsequent antioxidant administration. Bone mineral density values were evaluated in all the groups. Serum calcium, phosphorus, alkaline phosphatase (ALP) enzyme activities and 24 hours urine calcium excretion levels were measured. Kruskal-Wallis test was used to compare the all groups. Between two group comparisons, the Mann-Whitney U test was used. Results: There was no significant difference in terms of bone mineral density values only between control group and cadmium exposure group (p 0.05). Mean bone mineral density values obtained in cadmium + concurrent taurine and cadmium + subsequent taurine groups were significantly lower than all the other groups (p<0.05). 24 hours urine calcium excretion levels were significantly higher in groups which taurine and n-asetylcystein were administered after cadmium exposure. Conclusion: Taurine, which is thought to have protective effects as an antioxidant caused a marked bone damage after exposure to cadmium. Further studies are needed to clarify this effect of taurine.Öğe Gastric damage related to radioactive iodine treatment and the protective effect of amifostine.(Scientific Publishers India, 2017) Sezer, Atakan; Celik, Mehmet; Usta, Ufuk; Altun, Gulay DurmusIntroduction: The aim of this study was to evaluate the gastric damage related to high dose radioactive iodine treatment during thyroid cancer treatment in an experimental rat model and evaluate histopathologically the radioprotective effect of amifostine. Methods and findings: 40 adult rats were enrolled into the study. Radioactive iodine treatment with 30 mCi/kg I-131 was applied via orogastric tube simulating radioiodine ablation treatment (RAI) in thyroid cancer in all rats. After RAI subjects were divided into 2 groups: Group Orogastric RAI (Group OG, n: 20): Rats received no radioprotective agent but serum physiologic. Group Amifostine RAI (Group AP, n: 20): Rats received 200 mg/kg amifostine intraperitoneally 30 minutes before I-131 application. On the 1st, 3rd, 5th and 7th days of experiment rats were sacrificed for histopathological evaluation. Gastric tissues were excised and tissue damage was assessed by using histopathological scoring. Total pathology score revealed a significant change on the 7th day. The subjects in Group OG had histopathological changes, while only one subject in Group AP was found to have pathologic changes (X2=39.7 df (28), p=0.04). The common histopathological findings were striking mucosal and intraepithelial leucocytic infiltration together with thinning of the mucosa, regenerative changes, and reactive atypia. Conclusions: RAI treatment causes gastric mucosal injury and amifostine was found to decrease radioactive iodine treatment related gastric damage.Öğe Hypertension and salt: Intake or sensitivity?(Oxford Univ Press, 2006) Sen, Saniye; Ustundag, Sedat; Altun, Gulay Durmus; Okten, Omur; Sipahi, Tammam; Demirkan, Bora[Abstract Not Available]Öğe Intrathoracic toxic thyroid nodule causing hyperthyroidism with a multinodular normal functional cervical thyroid gland(Medknow Publications & Media Pvt Ltd, 2016) Serim, Burcu Dirlik; Korkmaz, Ulku; Can, Unal; Altun, Gulay DurmusRadionuclide scintigraphy with 1- 131 and Tc- 99m pertechnetate ( 99mTc04) has been widely used in detecting toxic nodules. Intrathoracic goiter usually presents as an anterior mediastinal mass. Mostly the connection between intrathoracic mass and the cervical thyroid gland is clearly and easily identified occurring as a result of inferior extension of thyroid tissue in the neck, which is called as secondary intrathoracic goiter. Completely separated, aberrant or in other words primary intrathoracic goiters arise as a result of abnormal embryologic migration of ectopic thyroid closely associated with aortic sac and descend into the mediastinum. Intrathoracic goiters are generally nontoxic nodules existing with mass effect without causing hyperthyroidism. However, mostly reported cases had enlarged thyroid glands in the neck. This report demonstrates the usefulness of 1- 131 and 99mTc0 4 scintigraphy for detecting intrathoracic goiter causing hyperthyroidism with a normal functioned cervical thyroid gland.Öğe PET/CT for Early Detection of COVID-19 Pneumonia: Diffuse Fluorodeoxyglucose Uptake in the Lungs without any Additional Changes in a Patient with Breast Cancer(Galenos Yayincilik, 2021) Ozdemir, Busra; Gunay, Burak; Karabulut, Derya; Altun, Gulay DurmusCoronavirus disease-2019 (COVID-19), which causes infections in the upper and lower respiratory tract, became a pandemic shortly after it was first diagnosed in Wuhan city, China. Many people are affected with high mortality rates and severe respiratory distress syndrome. During this pandemic, all physicians paid attention to the findings of COVID-19. Suggestive findings in (18)fluorine-fluorodeoxyglucose (F-18-FDG) positron emission tomography/computed tomography (PET/CT) were characterized as increased F-18-FDG uptake in bilateral peripheral consolidative areas and ground glass opacities. We aimed to show diffuse FDG uptake in PET images with indefinable lesions in CT as a suspicious finding for early COVID-19.Öğe Pre-therapy Iodine-131 Uptake Value as a Prediction Method for Metastatic Lymph Node Status in Patients with Differentiated Thyroid Carcinoma(Bentham Science Publ Ltd, 2017) Aktas, Gul Ege; Demir, Selin Soyluoglu; Ustun, Funda; Sarikaya, Ali; Altun, Gulay DurmusBackground: We hypothesized that postoperative lymph node status would affect I-131 uptake (RIU) due to pathophysiological behavior of benign and malign thyroidal tissue. This retrospective study was designed to assess whether RIU would predict the presence of lymph node metastasis (LNM). Methods: Data for differentiated thyroid cancer patients who received postoperative I-131 therapy at our institution between 2013 and 2016 were reviewed. Age, histopathology, TSH, Tg, anti-Tg, 2 and 24 hour RIU (2-24RIU), ultrasonography, I-131 dose, scans were reviewed. Patients were divided into groups according to lymph node status. The Delta RIU was calculated (Delta RIU=24RIU-2RIU) to define different metabolic behavior of I-131. Patients were grouped according to Delta RIU to assess the sensitivity, specificity, negative/positive predictive values, accuracy of Delta RIU predicting LNM. Results: 198 patients (38 males/160 females, age: 47 +/- 14 years) who received mean: 118 +/- 27 mCi I-131 were enrolled in the study. There was no difference between ages, TSH level, 2RIU values and the I-131 therapy dose of patients with and without LNM. Tg, anti-Tg, 24RIU, Delta RIU values were higher in patients with LNM. Patients with Delta RIU >= 1% had higher Tg values (mean +/- std: 16.63 +/- 46.53 vs. 6.70 +/- 31.18, p: 0.04). When Delta RIU >= 1% was used for predicting LNM, sensitivity, specificity, positive, negative predictive values, diagnostic accuracy were, 66%, 72%, 64%, 74 %, and 70% respectively. Conclusion: RIU was evaluated to predict neck LN status in this study. The sensitivity and specificity were comparable with modalities which are commonly used for determination of LNM. In light of the results of this study, when a pre-therapy RIU increase in time is observed, carrying out further investigation protocols for LNM, would contribute to pre-therapy staging.Öğe Radioprotective Effects of Amifostine, L-Carnitine and Vitamin E in Preventing Early Salivary Gland Injury due to Radioactive Iodine Treatment(Bentham Science Publ Ltd, 2019) Torun, Nese; Muratli, Asli; Serim, Burcu Dirlik; Ergulen, Alev; Altun, Gulay DurmusObjective: Standard treatment of differentiated thyroid cancer includes total thyroidectomy and high-dose Radioactive Iodine Therapy (RIT) for ablation of remnant thyroid tissue. When administered systemically, RIT can cause radiation-induced damage in non-targeted normal tissues. The aim of the present study was to compare the protective effects of amifostine (AMI), L-Carnitine (LC), and Vitamin E (EVIT) against high dose radioactive iodine treatment induced Salivary Gland (SG) damage using SG scintigraphy and histopathological examination. Methods: Forty adult guinea pigs were studied. Twenty guinea pigs receive 555-660 MBq (131)Iodine intraperitoneally (IP) to ablate the thyroid and impair the parenchymal function of the SGs. The animals were divided into eight groups as follows: (1) Group 1 (control): 1 mL IP PS (physiological saline); (2) Group 2: single dose of 200 mg/kg IP AMI one hour prior to 1 mL IP PS; (3) Group 3: 200 mg/kg IP LC and 1 mL IP PS for 10 days; (4) Group 4: 40 mg/kg intramuscular (IM) EVIT and 1 mL IP PS for 10 days; (5) Group 5: IP RIT after premedication; (6) Group 6: Single dose of 200 mg/kg IP AMI one hour prior to RIT and IP RIT after premedication; (7) Group 7: IP RIT after premedication and 200 mg/kg IP LC for 10 days starting one day before RIT; and (8) Group 8: IP RIT after premedication and 40 mg/kg IM EVIT for 10 days starting one day before RIT. Scintigraphy was performed 1 month after treatment. SGs were examined by light microscopy and a histopathological scoring system was used to assess the degree of SG damage. Results: There were significant differences in the body weight and thyroid hormone levels between the groups after treatment. Conclusion: The individual use of AMI, LC and EVIT for radioprotection yield different levels of protection against radioactive iodine treatment injury in SGs; however, none of the agents could provide absolute protection at the doses administered in this experimental model.Öğe Skeletal trauma and torture detection with 18F-FDG PET/CT(Soc Nuclear Medicine Inc, 2016) Altun, Gurcan; Serim, Burcu Dirlik; Ustun, Funda; Altun, Gulay Durmus[Abstract Not Available]Öğe Tumor Microenvironment Features as Predictive Biomarkers in Metastatic Differentiated Thyroid Cancer and Their Relationship With 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) Metabolic Parameters(Springernature, 2023) Soyluoglu, Selin; Tastekin, Ebru; Andac, Burak; Korkmaz, Ulku; Orun, Seyma Gizem; Altun, Gulay DurmusObjective: The role of the tumor microenvironment in tumor progression and treatment response is being investigated for different types of cancer. This study aimed to determine the relationships between tumor microenvironment, histopathology, 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT)-based metabolic parameters, treatment response, and overall survival (OS) in metastatic differentiated thyroid cancer (DTC).Methods: Metastatic DTC patients who underwent 18F-FDG PET/CT between 2015-2019 were evaluated. Clinicopathological, histopathological features and PET/CT parameters of patients were recorded. Microenvironmental characteristics of the primary tumor, such as mitosis, intratumoral and peritumoral lymphocytosis, intratumoral and peritumoral fibrosis, were evaluated from the tissue samples. The relationships between these factors were statistically analyzed.Results: Sixty-five patients (38 females, 27 males, age: 49 +/- 15 years) were included. Mitosis, intra/peritumoral lymphocytosis, and intra/peritumoral fibrosis were frequent; however, none of them had a statistically significant association with PET-positive metastases, treatment response, or OS. Univariate analysis showed that gender, size, thyroglobulin values, residual thyroid tissue, PET-positive metastases, and maximum standardized uptake value (SUVmax) were significant predictors of OS. At multivariate analysis, PET-positive metastases (I-IR=-2.65, 95%CI 0.007-0.707, p=0.024) and SUVmax (I-IR=-2.74, 95%CI 0.006-0.687, p=0.023) were the only independent predictors for OS.Conclusion: Our study revealed that microenvironmental characteristics of the primary tumor did not show prognostic significance in metastatic DTC. PET-positive metastases and SUVmax levels were the only significant factors that predicted overall survival in DTC. Supporting the results of our study with further studies with a larger sample size may be necessary to determine the relationship between the tumor microenvironment and prognosis in DTC.
