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Glioblastoma (GBM) is the most common primary malignant type of brain neoplasm in adults and carries a dismal prognosis. The current standard of care for GBM is surgical excision followed by radiation therapy (RT) with concurrent and adjuvant temozolomide-based chemotherapy (TMZ) by six additional cycles. In addition, antiangiogenic therapy with an antivascular endothelial growth factor (VEGF) agent has been used for recurrent glioblastoma. Over the last years, new posttreatment entities such as pseudoprogression and pseudoresponse have been recognized, apart from radiation necrosis. This review article focuses on the role of different imaging techniques such as conventional magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), dynamic contrast enhancement (DCE-MRI) and dynamic susceptibility contrast (DSE-MRI) perfusion, magnetic resonance spectroscopy (MRS), and PET/SPECT in differentiation of such treatment-related changes from tumor recurrence.

Our study presents the computational implementation of an air lubrication system on a commercial ship with 154,800 m3 Liquified Natural Gas capacity. The air lubrication reduces the skin friction between the ship’s wetted area and sea water. We analyze the real operating conditions as well as the assumptions, that will approach the problem as accurately as possible. The computational analysis is performed with the ANSYS FLUENT software. Two separate geometries (two different models) are drawn for a ship’s hull: with and without an air lubrication system. Our aim is to extract two different skin friction coefficients, which affect the fuel consumption and the CO2 emissions of the ship. A ship’s hull has never been designed before in real scale with air lubrication injectors adjusted in a computational environment, in order to simulate the function of air lubrication system. The system’s impact on the minimization of LNG transfer cost and on the reduction in fuel consumption and CO2 emissions is also examined. The study demonstrates the way to install the entire system in a new building. Fuel consumption can be reduced by up to 8%, and daily savings could reach up to EUR 8000 per travelling day.

The effective resolution of positron emission tomography (PET) can be significantly degraded by patient motion during data acquisition. This is especially true in the thorax due to respiratory motion. This study concentrates on the improvement of motion correction algorithms both in terms of image quality and computational cost. In this paper, we present a novel motion-compensated image reconstruction (MCIR) algorithm based on a parabolic surrogate likelihood function instead of the loglikelihood function of the expectation maximization (EM) algorithm. The theoretical advantage of the parabolic surrogate algorithm lies within the fact that its loglikelihood is upper bounded by the EM loglikelihood, thus it will converge faster than EM. This is of particular importance in PET motion correction, where reconstructions are very computationally demanding. Relaxation parameters were also introduced to converge closer to the maximum likelihood (ML) solution and achieve lower noise levels. Image reconstructions with embedded relaxation parameters actually converged to better solutions than the corresponding ones without relaxation. Motion-compensated parabolic surrogates were indeed shown to accelerate convergence compared to EM, without reaching a limit cycle. Nonetheless, with the incorporation of ordered subsets in the reconstruction setting, the improvement was less evident.

Cancer theragnostics is a novel approach that combines diagnostic imaging and radionuclide therapy. It is based on the use of a pair of radiopharmaceuticals, one optimized for positron emission tomography imaging through linkage to a proper radionuclide, and the other bearing an alpha- or beta-emitter isotope that can induce significant damage to cancer cells. In recent years, the use of theragnostics in nuclear medicine clinical practice has increased considerably, and thus investigation has focused on the identification of novel radionuclides that can bind to molecular targets that are typically dysregulated in different cancers. The major advantages of the theragnostic approach include the elimination of multi-step procedures, reduced adverse effects to normal tissues, early diagnosis, better predictive responses, and personalized patient care. This review aims to discuss emerging theragnostic molecules that have been investigated in a series of human malignancies, including gliomas, thyroid cancer, neuroendocrine tumors, cholangiocarcinoma, and prostate cancer, as well as potent and recently introduced molecular targets, like cell-surface receptors, kinases, and cell adhesion proteins. Furthermore, special reference has been made to copper radionuclides as theragnostic agents and their radiopharmaceutical applications since they present promising alternatives to the well-studied gallium-68 and lutetium-177.

Background: Glioblastoma, the most common malignant primary brain tumor in adults, continues to present a major therapeutic challenge, with a median survival of only 12–15 months and a 5-year survival rate below 2%. Despite aggressive treatment—including maximal surgical excision, radiation, and temozolomide (TMZ) chemotherapy—recurrent disease is nearly universal due to the tumor’s infiltrative nature. Objectives: To address the critical need for improved diagnostic and therapeutic strategies for glioblastoma multiforme (GBM), we have developed an innovative theranostic molecule, [99mTc]Tc-AGT-7. Methods: AGT-7 integrates diagnostic and therapeutic modalities comprising [99mTc]Tc-TF (a nuclear medicine imaging agent) and TMZ. The diagnostic component has been tailored to selectively accumulate in glioma mitochondria. A chelating moiety enables radiolabeling with technetium-99m (99mTc) for precise Single-Photon Emission Computed Tomography (SPECT) imaging. The therapeutic arm includes the tethering of a TMZ moiety for localized cytotoxicity. Conclusions: In vitro studies illustrated that AGT-7 has potent cytotoxic effects in GBM cell lines (T98 and U87), with greater efficacy than TMZ, and toxicity assays in zebrafish embryos indicated a favorable safety profile. Biodistribution studies in CFW mice demonstrated that [99mTc]Tc-AGT-7 exhibited a ~10-fold lower heart uptake compared to [99mTc]Tc-TF, implying reduced off-target cardiac localization. This significantly lowers the risk of cardiotoxicity and enhances AGT-7’s potential as a glioma-targeted theranostic agent.

Treatment for brain gliomas is a combined approach of surgery, radiation therapy and chemotherapy. Nevertheless, high-grade gliomas usually recur despite treatment. Ionizing radiation therapy to the central nervous system may cause post-radiation damage. Differentiation between post-irradiation necrosis and recurrent glioma on the basis of clinical signs and symptomatology has not been possible. Computed tomography (CT) and magnetic resonance imaging (MRI) suffer from significant limitations when applied to differentiate recurrent brain tumor from radiation necrosis. We reviewed the contribution of recent MRI techniques, single-photon emission CT and positron emission tomography to discriminate necrosis for glioma recurrence. We concluded that despite the progress being made, further research is needed to establish reliable imaging modalities that distinguish between true tumour progression and treatment-related necrosis.

Background and Objectives: Vitamin D (Vit D) deficiency has been implicated in various conditions, including cardiovascular disease. The purpose of this retrospective study was to investigate the incidence of patients with myocardial ischemia in relation to their serum levels of vitamin D. Materials and Methods: A 64-month search (January 2016 to April 2021) in our database of the Nuclear Medicine Laboratory revealed 113 patients who had both myocardial perfusion imaging with single photon emission computed tomography (MPI SPECT) and Vit D measurements. MPI SPECT obtained myocardial images during both stress (summed stress score, SSS) and rest (summed rest score, SRS). Abnormal MPI SPECT was when the SSS was ≥4. Vit D was determined by radioimmunoassay (RIA). Patients with Vit D values <10 ng/mL, 10–29 ng/mL and ≥30 ng/mL were defined as having a deficiency, insufficiency and sufficiency, respectively. Results: Among patients, 46/113 (40.7%) were male and 67/113 (59.3%) were female. Abnormal MPI was found in 58/113 (51.3%) patients. Vit D deficiency was noted in 20/113 (17.7%) patients, insufficiency in 86/113 (76.1%) patients, and normal Vit D was noted in only 7/113 (6.2%) patients. Sixteen of the 20 patients (80%) with Vit D deficiency, and 38/86 (44.2%) with insufficiency had an abnormal MPI SPECT. In contrast, only 1/7 (14.3%) patients with sufficient Vit D levels had an abnormal MPI SPECT. The Mann-Whitney U-test showed that ischemia reduced the values of Vit D. Correlation analysis showed a negative association of Vit D levels with SSS (rho = −0.232, p = 0.014) and SRS (rho = −0.250, p = 0.008). Further evaluation with a Vit D cut off 20 ng/mL retrieved no statistical significance. Finally, Vit D and gender were independently associated with myocardial ischemia. Conclusions: Low Vit D levels may represent a risk factor for myocardial ischemia.

Assessment of the grade and type of glioma is of paramount importance for prognosis. Tumour proliferative potentials may provide additional information on the behaviour of the tumour, its response to treatment and prognosis. The purpose of this study was to investigate the correlation between diffusion tensor imaging (DTI), dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) and 99mTc-Tetrofosmin brain single-photon emission computed tomography (SPECT), and the tumour grade and Ki-67 labelling index in newly diagnosed gliomas. Study was made of patients with suspected glioma on brain MRI between December 2010 and January 2012, by DTI, DSC MRI and 99mTc-Tetrofosmin brain SPECT. The proliferative activity of each tumour was measured by deriving the Ki-67 proliferation index from immunohistochemical staining of tumour specimens. Glioma was newly diagnosed in 25 patients (17 men, 8 women, aged 19–79 years, median 55 years). The Ki-67 index ranged from 1% to 80% (mean 19.4%). On evaluation of the relationship between the 99mTc-Tetrofosmin tumour uptake by gliomas was found to be significantly correlated with cellular proliferation (rho=0.924, p<0.0001). Regarding DTI, significant negative correlation was demonstrated between the apparent diffusion coefficient (ADC) ratio and the Ki-67 index (rho=−0.545, p=0.0087). Significant correlation was also observed between the fractional anisotropy (FA) ratio and the Ki-67 index (rho=0.489, p=0.02). Strong correlation was found between relative cerebral blood volume (rCBV) and Ki-67 index (rho=0.853, p<0.0001), and between the 99mTc-Tetrofosmin lesion-to-normal (L/N) uptake ratio and rCBV (rho=0.808, p≤0.0001). Significant negative correlation was demonstrated between the 99mTc-Tetrofosmin L/N ratio and ADC ratio (rho=−0.513, p=0.014). These imaging techniques were able to distinguish between low-grade and high-grade gliomas. Findings on DSC MRI and brain SPECT with 99mTc-Tetrofosmin metrics were more closely correlated with glioma cellular proliferation.

Keywords: Plasmacytoma, Bone scintigraphy, Multiple myeloma Anahtar Sözcükler: Plazmasito, Kemik sintigrafisi, Multipl myelom A 54-year-old woman was subjected to a routine annual chest X-ray for work license renewal, which showed a hyperdense lesion of the left 8th rib (Figure 1). During diagnostic workup, fludeoxyglucose-positron emission tomography should be performed, if available, to rule out smoldering multiple myeloma and monitor response to treatment [3,4]. Conflict of Interest: The authors of this paper have no conflicts of interest, including specific financial interests, relationships, and/or affiliations relevant to the subject matter or materials included. ©Copyright 2019 by Turkish Society of Hematology Turkish Journal of Hematology, Published by Galenos Publishing House Address for Correspondence/Yazışma Adresi: Chrissa SIOKA, M.D., School of Health Sciences, University Hospital of Ioannina Faculty of Medicine, Department of Nuclear Medicine, Ioannina, Greece Phone : +30 26510 07514 E-mail : csioka@yahoo.com ORCID-ID: orcid.org/0000-0002-2184-4945 Received/Geliş tarihi:

Assessment of the grade and type of glioma is of paramount importance for prognosis. Tumour proliferative potentials may provide additional information on the behaviour of the tumour, its response to treatment and prognosis. The purpose of this study was to investigate the correlation between diffusion tensor imaging (DTI), dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) and (99m)Tc-Tetrofosmin brain single-photon emission computed tomography (SPECT), and the tumour grade and Ki-67 labelling index in newly diagnosed gliomas. Study was made of patients with suspected glioma on brain MRI between December 2010 and January 2012, by DTI, DSC MRI and (99m)Tc-Tetrofosmin brain SPECT. The proliferative activity of each tumour was measured by deriving the Ki-67 proliferation index from immunohistochemical staining of tumour specimens. Glioma was newly diagnosed in 25 patients (17 men, 8 women, aged 19-79 years, median 55 years). The Ki-67 index ranged from 1% to 80% (mean 19.4%). On evaluation of the relationship between the (99m)Tc-Tetrofosmin tumour uptake by gliomas was found to be significantly correlated with cellular proliferation (rho=0.924, p<0.0001). Regarding DTI, significant negative correlation was demonstrated between the apparent diffusion coefficient (ADC) ratio and the Ki-67 index (rho=-0.545, p=0.0087). Significant correlation was also observed between the fractional anisotropy (FA) ratio and the Ki-67 index (rho=0.489, p=0.02). Strong correlation was found between relative cerebral blood volume (rCBV) and Ki-67 index (rho=0.853, p<0.0001), and between the (99m)Tc-Tetrofosmin lesion-to-normal (L/N) uptake ratio and rCBV (rho=0.808, p ≤ 0.0001). Significant negative correlation was demonstrated between the (99m)Tc-Tetrofosmin L/N ratio and ADC ratio (rho=-0.513, p=0.014). These imaging techniques were able to distinguish between low-grade and high-grade gliomas. Findings on DSC MRI and brain SPECT with (99m)Tc-Tetrofosmin metrics were more closely correlated with glioma cellular proliferation.