Current radiopharmaceuticals最新文献

Background: A promising material used in radiation synovectomy of small joints is hydroxyapatite, labeled with 177Lu. During the design and production of radiopharmaceuticals, the condition of the radiolabeling process directly influences the radiochemical yield and consequently the quality of the final product so this process necessitates precise optimization.

Methods: In this investigation, a central composite design based on response surface methodology and artificial neural networks modeling coupled with genetic algorithm technique is applied to build predictive models and explore key parameters' effect in hydroxyapatite's radiolabeling process with 177Lu radionuclide. The variables that directly affected the labeling reaction were the initial 177Lu radioactivity, pH, radiolabeling reaction time, and temperature.

Results: Based on the validation data set, the statistical values demonstrate that the artificial neural networks model performs better than the response surface methodology model. The artificial neural networks model has a small mean squared error (9.08 artificial neural networks < 12.36 response surface methodology) and a high coefficient of determination (R2: 0.99 artificial neural networks > 0.93 response surface methodology). The optimum conditions to achieve maximum radiochemical yield based on response surface methodology using artificial neural networks modeling coupled with genetic algorithm were at the initial radioactivity of 177Lu radionuclide = 0.082 Gigabecquerel (GBq), pH = 6.75, time= 22 (min), and temperature = 37.8 (oC) Conclusion: The ability to generate more data with fewer experiments for optimization and improved production is a pertinent advantage of multivariate optimization methods over traditional methods in radiation-related activities. The central composite design and artificial neural network- genetic algorithm optimization approaches are successfully utilized to create prediction models and investigate the impact of critical variables in the radiolabeling of hydroxyapatite with 177Lu radionuclide.

Background: Many studies have reported Translocator Protein (TSPO) overexpression in many neurological disorders. Carbon-11[11C]PBR28 is a widely used TSPO Positron Emission Tomography (PET) radiopharmaceutical. We have compared HPLC-based purification with cartridge-based purification and performed PET-MR imaging in ALS patients.

Methods: [11C]PBR28 has been synthesized using an HPLC-based and cartridge-based purification technique in the FX2C chemistry module. All necessary quality controls were performed and compared. We injected 350 ± 20 MBq of the [11C]PBR28 intravenously into human patients (n = 6) diagnosed with amyotrophic lateral syndrome (ALS) and performed simultaneous PETMR dynamic imaging.

Results: The radiochemical purity was greater than 95% with both methods. The radiochemical yield was 11.8 ± 3.3%, and molar activity was 253 ± 20.9 GBq/μmol with a total synthesis time of 25 ± 2 min in the HPLC-based purification method. Whereas the radiochemical yield was 53.0 ± 3.6%, and molar activity was 885 ± 17.7 GBq/μmol with a total synthesis time of 12 ± 2 min in the cartridge-based purification method. We have compared PET-MR imaging of ALS limb onset (n =3) with ALS bulbar and limb onset (n =3), and there was a difference in time activity curves. The activity was higher in the precentral gyrus and cerebellum at 2.5 ± 0.5 min in bulbar cases with an SUV of 2.3 ± 0.3, whereas ALS limb onset showed the highest uptake at 0.5 ± 0.2 min with an SUV of 1.5 ± 0.2.

Conclusion: The cartridge-based method provided higher radiochemical yield and molar activity.

Objective: The Ga68-DOTATATE PET/CT scan is an alternative imaging modality for the follow-up of children with neuroblastoma when the I123-MIBG scan was negative or weak. Somatostatin receptors (SSR) can be expressed in neuroblastoma lesions, and when this happens, targeting these receptors may be a good alternative to treating this disease in addition to conventional treatments. Our aim is to focus on the interpretation of one of the physiological tracer uptake sites, the uncinate process of the pancreas, using DW-MRI scans.

Methods: We present and discuss 4 cases with neuroblastoma for a technical note. Imaging scans for SSR were performed using Ga68-DOTATE PET/CT, and all showed varying degrees of increased uptake at the uncinate process of the pancreas on PET/CT images. We also performed a DW-MRI study to distinguish physiologic uptake in this region of the pancreas from metastatic involvement.

Results: Two of them showed diffusion restriction, with one of them also showing multiple masses within the liver. The other 2 children with high pancreatic uncinate process uptake did not exhibit any findings that indicated pancreatic involvement in the disease, based on DW-MRI images and clinical findings.

Conclusion: We recommend comparing DW-MRI scans and SSR-PET/CT scans to determine the true state of physiologically elevated SSR concentration and consequently indicate increased uptake on the images. The radiotracer concentration at the high uptake site did not appear to correlate with malignant involvement of the organ. The higher number of patients may allow a statistical comparison of the tracer with malignancy status.

Background: Radiation-induced damage to the hematopoietic and gastrointestinal systems, especially the intestine, is a major concern for individuals exposed to whole-body radiation during an accident. Resveratrol has shown potential in mitigating radiation-induced toxicity, but its efficacy may be limited by its low bioavailability. In this study, we aimed to evaluate the effectiveness of resveratrol-loaded polymeric-based nanocapsules in mitigating radiation-induced injury in the hematopoietic system and intestine after whole-body exposure to radiation.

Methods: Sixty male mice were randomly divided into four groups: control, radiation (single dose of 7.2 Gy of X-ray) only, resveratrol-loaded polymeric-based nanocapsules (RES-ACN) only, and radiation plus RES-ACN. Mice were exposed to a single dose of 7.2 Gy of X-ray radiation. RES-ACN was administered to the mice starting 24h after irradiation up to day 7 post-irradiation. Then, blood and tissue samples were collected for complete blood count and histopathological and biochemical evaluation. Survival analyses were also conducted.

Results: The findings showed that RES-ACN significantly mitigated radiation-induced injury to the hematopoietic system and intestine. The histopathological evaluation showed the mitigation of villi shortening, inflammation, and mucous layer thickness following treatment with RES-ACN. Biochemical evaluation also demonstrated a significant increase in the activity of glutathione peroxidase and superoxide dismutase and a significant reduction in the concentrations of malondialdehyde and nitric oxide. Treatment with RES-ACN also showed a significant improvement in some of the blood parameters and increased survival compared to radiation only.

Conclusion: The findings suggest that resveratrol-loaded polymeric-based nanocapsules can be an effective approach to mitigate radiation-induced damage to the hematopoietic system and intestine after whole-body exposure to X-ray radiation in mice. Further research is needed to explore the optimal dose and timing of resveratrol administration and to investigate the potential for clinical translation of this approach.

Introduction: Metformin induces radiation sensitivity in cancer cells, including colorectal cancer cells; however, the exact molecular mechanisms underlying its radiosensitive effects are not yet known. In this study, we investigated the role of the p53/miR-34a/SIRT1 pathway in the radiosensitivity of colon cancer cells.

Methods: The study was carried out from 2020 to 2022 at the Qazvin University of Medical Science's Cellular and Molecular Research Center. Two colorectal cancer cell lines (SW480 and SW620) obtained from primary and secondary tumors derived from a single patient were used as the study samples. After subjecting the cells to 50 Gy of radiation, we generated radioresistant cell lines. Resistant cells were treated with 50 μM metformin. Metformin-treated and untreated resistant cells constituted the study groups. The expression levels of miR-34-a and Sirtunin1 (SIRT1) were evaluated using Quantitative Real-time PCR. The rates of cell proliferation and apoptosis were assessed using a Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Western blot analysis was performed to quantify the expression of proteins. For statistical analysis, the Student's ttest was carried out to examine the mean differences between the two groups, and analysis of variance (ANOVA) was used to examine additional groups.

Results: Our results showed that the expression of miR-34-a was downregulated (0.29 ± 0.11) in radiation-resistant cancer cells (P <0.001), while the expression of SIRT-1 was upregulated (4.5 ± 0.25) (P <0.001). Metformin increased the radiosensitivity of colon cancer cells in a time- and dose-dependent manner. Treatment with 50 μM metformin after 48h caused decreased cell viability and increased apoptosis in resistant cells. We observed downregulation of SIRT-1 (1.1 ± 0.45) and upregulation of miR-34-a (4.3 ± 1.3) (P <0.001) in metformin-treated cells. In contrast, western blotting results showed the upregulation of acetylated P53 in metformin-treated cells. Metformin function was reversed by SIRT1 inhibitors or by transfection with miR-34-a overexpressing plasmids.

Conclusion: Based on these results, one of the radiosensitivity mechanisms of metformin in colorectal cancer is the modulation of the p53/miR-34a/SIRT1 loop.

Background: In the context of modern oncology, radiogenic elements have emerged as pivotal tools for targeted cancer therapies. Elements like Iodine-131 and Yttrium-90 offer unique radiological properties that allow precise treatment delivery. This article explores their growing importance and potential in reshaping the landscape of cancer therapy.

Methods: Utilizing a systematic literature search, relevant studies, clinical trials, and research articles were collected from databases. The selected material was scrutinized to extract insights into the mechanisms, applications, advantages, and challenges of radiogenic elements. These results are combined in the study to give a perceptive picture of how contemporary oncology treatment is developing.

Results: The article reveals a comprehensive analysis of the outcomes derived from the study of radiogenic elements in contemporary cancer treatment. The results highlight the diverse applications of radionuclides like Iodine-131, Yttrium-90, and actinides in targeted therapies. It showcases their ability to selectively damage cancer cells while sparing healthy tissues, emphasizing precision and efficacy. The review underscores the increasing importance of personalized medicine, combination therapies, and the potential of emerging alpha-particle-based treatments. Furthermore, the results shed light on the challenges posed by radiation safety and potential side effects, prompting a need for vigilant management. This comprehensive examination of results provides a nuanced understanding of the pivotal role that radiogenic elements play in shaping the future of modern oncology therapy.

Conclusion: The article examines the role of radiogenic elements in contemporary cancer treatment. It highlights the significance of elements like 131I, 90Y, and actinides in targeted therapies, discussing their mechanisms and applications. The article emphasizes personalized medicine, combination therapies, and emerging alpha-particle-based treatments. Challenges, including radiation safety and side effects, are also addressed. The review anticipates a promising future where radiogenic elements contribute to precise, effective, and patient-centered cancer care.

Aim: This study intended to compare the radiation dose estimates to target and nontarget liver compartments from 99mTc-MAA SPECT/CT and 90Y-PET/MR scans in liver tumors treated by 90Y-glass microspheres.

Material and methods: Dose estimation was performed for twenty-three eligible patients (13M, 10F) after 99mTc-MAA simulation using SPECT/CT imaging, and over 90Y-PET/MR images after 90Y-microsphere therapy. Simplicit90Y™ software was used for voxel-based dosimetry over the liver parenchyma. Dose estimates were obtained for whole healthy liver (HL), healthy injected liver (HIL), and tumor volumes. Pearson correlation, Bland-Altman plot, and Wilcoxon signed-ranks test were used for statistical analysis.

Results: The mean tumor dose was 270±111 Gy, the whole liver parenchyma dose was 26 ±12 Gy, and the healthy injected liver dose was 55±18 Gy from 99mTc-MAA simulation. 90YPET/ MR dosimetry yielded a mean tumor dose of 271±125 Gy, a HIL mean dose of 54±18 Gy, and a liver parenchyma dose of 25±12 Gy. An excellent agreement was demonstrated between tumor doses (R2=0.90) and liver doses (R2=0.87), while the agreement was less for HIL doses (R2=0.80). Wilcoxon signed-ranks test yielded no significant difference between the dose estimates for all liver compartments.

Conclusion: It was deduced that 99mTc-MAA SPECT/CT simulation provides valuable dose prediction in 90Y-glass microsphere therapy. Despite the difference in volume measurements and dose estimates with 90Y-PET/MR, the predictive value of the 99mTc-MAA simulation was not affected.

Objective: Traditional cell-based radiobiological methods are inadequate for assessing the toxicity of ionizing radiation exposure in relation to the microstructure of the extracellular matrix. Organotypic tissue slices preserve the spatial organization observed in vivo, making the tissue easily accessible for visualization and staining. This study aims to explore the use of fluorescence microscopy of physiologically relevant 3D tissue cultures to assess the effects of ionizing radiation.

Methods: Organotypic tissue slices were obtained by vibratome, and their mechanical properties were studied. Slices were exposed by two ionizing radiation sources; electron beams (80 Gy and 4 Gy), and soft gamma irradiation (80 Gy and 4 Gy). Two tissue culture protocols were used: the standard (37°C), and hypothermic (30°C) conditions. A qualitative analysis of cell viability in organotypic tissue slices was performed using fluorescent dyes and standard laser confocal microscopy.

Results: Biological dosimetry is represented by differentially stained 200-μm thick organotypic tissue sections related to living and dead cells and cell metabolic activity.

Conclusion: Our results underscore the ability of fluorescence laser scanning confocal microscopy to rapidly assess the radiobiological effects of ionizing radiation in vitro on 3D organotypic tissue slices.

Dementia (the most common cause of Alzheimer's disease) is defined as a chronic or progressive syndrome with disturbance of multiple cortical functions, the most important of them including memory, learning capacity, comprehension, orientation, calculation, language, and judgement. These cognitive impairments affect the quality of life, behavior, and social relations. Techniques of nuclear medicine provide feasible ways to record the intracellular alterations of disease and deficiencies. In these non-invasive manners, the hippocampal-neocortical disconnection may partly explain the hypo-metabolism incident found in Alzheimer's disease. Based on this fact, the study of all these mechanisms of action is conceivable and achievable by radiopharmaceuticals. This review is aimed at the presentation of radiopharmaceuticals that are developed for the detection of Alzheimer's disease in preclinical and clinical trials.

Background and purpose: Radiopharmaceuticals are radioactive compounds used for diagnostic or therapeutic purposes which are most often administered intravenously. Adverse events that may induce both adverse reactions and drug-to-drug interactions with changes in expected biodistribution, potentially affecting patient safety and diagnostic accuracy. Adverse reactions are relatively rare due to the small doses and under-reporting is the norm. The aim of this study is to increase awareness of the need to report in order to create protocols for the management of such adverse events among professionals in a Nuclear Medicine Department.

Methods: A reporting system was established a decade ago through an electronic form to enhance adverse event registration. The radiopharmacist collects data for further communication with National Health authorities and develops an annual report with recommendations on the management of these adverse events.

Results: A total of 128 reports were collected, including 65 cases of extravasations, 18 adverse reactions, and 45 drug interactions. Over the years, reporting has been increasing, adverse reactions occurred at a higher incidence than reported in the literature, and each anomalous biodistribution was analysed for possible drug interaction. The annual reports have been used to develop a local guideline for the management of adverse reactions and recommendations for discontinuation of treatment to avoid interactions with radiopharmaceuticals.

Conclusion: The recognition of adverse events associated with radiopharmaceuticals is increasing, underlining the need for vigilant reporting and improved management strategies. An efficient reporting system promotes awareness of possible interactions between radiopharmaceuticals and other medicines and their potential adverse reactions to enhance patient safety.