Infection is ubiquitous. However, its management is challenging for both the patients and the health-care providers. Scintigraphic imaging of infection dates back nearly half a century. The advances in our understanding of the pathophysiology of disease at cellular and molecular levels have paved the way to the development of a large number of radiopharmaceuticals for scintigraphic imaging of infection. These include radiolabeling of blood elements such as serum proteins, white blood cells (WBCs), and cytokines, to name a few. Infectious foci have also been imaged using a radiolabeled sugar molecule by taking advantage of increased metabolic activity in the infectious lesions. Literature over the years has well documented that none of the radiopharmaceuticals and associated procedures that facilitate imaging infection are flawless and acceptable without a compromise. As a result, only a few compounds such as Tc-hexamethylpropyleneamineoxime,F-FDG, the oldest but still considered as a gold standard In-oxine, and, yes, evenGa-citrate in some countries, have remained in routine clinical practice. Nonetheless, the interest of scientists and physicians to improve the approaches to imaging and to the management of infection is noteworthy. These approaches have paved the way for the development of numerous, innovative radiopharmaceuticals to label autologous WBCs ex vivo or even those that could be injected directly to image infection or inflammation without direct involvement of WBCs. In this review, we briefly describe these agents with their pros and cons and place them together for future reference.

Purpose Early and accurate diagnosis of Bladder cancer (BCa) will contribute extensively to the management of the disease. The purpose of this review was to briefly describe the conventional imaging methods and other novel imaging modalities used for early detection of BCa and outline their pros and cons. Methods Literature search was performed on Pubmed, PMC, and Google scholar for the period of January 2014 to February 2018 and using such words as “bladder cancer, bladder tumor, bladder cancer detection, diagnosis and imaging”. Results A total of 81 published papers were retrieved and are included in the review. For patients with hematuria and suspected of BCa, cystoscopy and CT are most commonly recommended. Ultrasonography, MRI, PET/CT using 18F-FDG or 11C-choline and recently PET/MRI using 18F-FDG also play a prominent role in detection of BCa. Conclusion For initial diagnosis of BCa, cystoscopy is generally performed. However, cystoscopy can not accurately detect carcinoma insitu (CIS) and can not distinguish benign masses from malignant lesions. CT is used in two modes, CT and computed tomographic urography (CTU), both for dignosis and staging of BCa. However, they cannot differentiate T1 and T2 BCa. MRI is performed to diagnose invasive BCa and can differentiate muscle invasive bladder carcinoma (MIBC) from non-muscle invasive bladder carcinoma (NMIBC). However, CT and MRI have low sensitivity for nodal staging. For nodal staging PET/CT is preferred. PET/MRI provides better differentiation of normal and pathologic structures as compared with PET/CT. Nonetheless none of the approaches can address all issues related for the management of BCa. Novel imaging methods that target specific biomarkers, image BCa early and accurately, and stage the disease are warranted.

Objective: Oxidative/nitrosative stress may be triggered by various sources, and ionizing radiation may also initiate oxidative/nitrosative stress. This is the first study; we aimed to investigate the induction of oxidative and nitrosative stress due to ionizing radiation in patients undergoing Tc-99m pertechnetate thyroid scintigraphy. Method: Totally 26 patients (16 female,10 male) undergoing Tc-99m pertechnetate thyroid scintigraphy were included in this study. The patients were aged between 20 and 50 years (58.0±16.3 years). The blood samples were taken from patients 20 minutes after intravenous injection of Tc-99m pertechnetate in the dose used clinically (5 miliCurie) before the patients were taken to the thyroid imaging. Control group was selected from 30 healthy subjects (15 female,15 male). The control group was aged between 17 and 72 years (57.0±14.0 years). The blood samples were taken both patients and control group for measuring antioxidant enzymes (catalase and superoxide dismutase), malondialdehyde, nitric oxide, and nitrotyrosine as oxidative/nitrosative stress biomarkers. Results: In this study, we found that activities of antioxidant enzymes increased in patients compared to control (p<0.05). Further, malondialdehyde levels as an indicator of oxidative stress were higher in patients than control group (p<0.05).The levels of nitric oxide and nitrotyrosine as nitrosative stress biomarkers also increased in patients compared to control groups (p<0.05). Conclusions: We thought that Tc-99m pertechnetate might cause an increase in reactive oxygen and nitrogen species and may cause oxidative/nitrosative damage at the cellular level. Our results indicated that the dose of Tc-99m pertechnetate given in these patients undergoing thyroid scintigraphy could be tolerable.

BACKGROUND:Ionizing radiation is a strong stimulator of reactive oxygen specises (ROS) and reactive nitrogen species (RNS). These reactive species may cause oxidative and nitrosative stress. In this study, we aimed to evaluate possible effects of 99m Technetium ( 99m Tc)-methoxyisobuthylisonitrite (MIBI), 99m Tc-dimercaptosuccinic acid (DMSA), 99m Tc-mercaptoacetyltriglycine (MAG-3) on oxidative and nitrosative stress biomarkers in patients who were performed myocardial perfusion scintigraphy (MPS) and renal scintigraphy.MATERIAL AND METHODS: Patients (n = 29) who were referred to nuclear medicine department were chosen as the patient group. They were divided into three subgroups according to the type of disease and 99m Tc labelled agent. The first patient group had MPS (n = 9). The second patient group had 99m Tc-DMSA renal scintigraphy (n = 12). The third patient group had 99m Tc-MAG-3 renal scintigraphy (n = 8). The blood samples were taken from first, second and third patient groups 1 h, 3 h, 45 min after injection of the agent, respectively. The samples were taken from healthy volunteers (n = 25) as a control group.Alterations in catalase (CAT),superoxide dismutase (SOD), malondialdehyde (MDA) levels as oxidative stress biomarkers and nitric oxide (NO) and 3-Nitrotyrosine (3-NTx) levels as nitrosative stress biomarkers in all blood samples were evaluated. RESULTS:Results of MPS and renal scintigraphy performed patients were compared with control group separately. CAT, SOD, MDA and 3-NTx levels were higher in the first group than the control group (p < 0.05). Although NO levels were higher in the first group than the control group, it was not statistically significant (p > 0.05). CAT and SOD levels were lower in second and third groups than the control group (p < 0.0 5). However, MDA, NO, 3-NTx levels were higher in second and third groups than the control group (p < 0.05). CONCLUSIONS:These results show that oxidative and nitrosative balance is impaired due to ionization radiation. These reactive species might stimulate an adaptive and protective cellular defense mechanism in irradiated cells soon after exposure to radiation. Thereby, this mechanism protect organism from the effects of low dose ionizing radiation.