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1.
Mol Imaging ; 23: 15353508241245265, 2024.
Article in English | MEDLINE | ID: mdl-38952398

ABSTRACT

This meeting report summarizes a consultants meeting that was held at International Atomic Energy Agency Headquarters, Vienna, in July 2022 to provide an update on the development of multimodality imaging by combining nuclear medicine imaging agents with other nonradioactive molecular probes and/or biomedical imaging techniques.


Subject(s)
Multimodal Imaging , Nuclear Medicine , Nuclear Medicine/methods , Nuclear Medicine/trends , Multimodal Imaging/methods , Humans
2.
Int J Mol Sci ; 25(13)2024 Jul 08.
Article in English | MEDLINE | ID: mdl-39000580

ABSTRACT

Peripheral artery disease (PAD) is classified as the narrowing or complete occlusion of the lower extremity arteries due to atherosclerosis. The risk of developing PAD increases with increased age and risk factors such as smoking, diabetes, hypertension, and hypercholesterolemia. Current treatment for PAD involves lifestyle and symptom management, statin and antiplatelet therapy, and/or surgical interventions to improve quality of life with varying efficacy. PAD affects approximately 5 to 6 percent of the global population, with this global burden continuing to increase. Despite the increase in disease prevalence, no gold standard functional diagnostic tool has been established for enabling early detection of the disease, appropriate medical management, and prediction of adverse outcomes for PAD patients. The visualization and quantification of the physiological consequences of PAD are possible by way of nuclear imaging: specifically, via scintigraphy, single-photon emission computed tomography (SPECT), and positron emission tomography (PET) imaging. These non-invasive modalities, when combined with targeted radionuclides, possess utility for detecting functional perfusion deficits and provide unique insight into muscle tissue- and vascular-level characteristics of PAD patients. This review discusses the past, present, and emerging applications of hybrid nuclear imaging modalities in the evaluation and monitoring of patients with PAD.


Subject(s)
Lower Extremity , Peripheral Arterial Disease , Positron-Emission Tomography , Tomography, Emission-Computed, Single-Photon , Humans , Peripheral Arterial Disease/diagnostic imaging , Peripheral Arterial Disease/diagnosis , Lower Extremity/diagnostic imaging , Lower Extremity/blood supply , Tomography, Emission-Computed, Single-Photon/methods , Positron-Emission Tomography/methods
3.
Mol Pharm ; 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39046432

ABSTRACT

This study aimed to evaluate a novel albumin-binding strategy for addressing the challenge of insufficient tumor retention of fibroblast activation protein inhibitors (FAPIs). Maleimide, a molecule capable of covalent binding to free thiol groups, was modified to conjugate with FAPI-04 in order to enhance its binding to endogenous albumin, resulting in an extended blood circulation half-life and increased tumor uptake. DOTA-FAPI-maleimide was prepared and radiolabeled with Ga-68 and Lu-177, followed by cellular assays, pharmacokinetic analysis, PET/CT, and SPECT/CT imaging to assess the probe distribution in various tumor-bearing models. Radiolabeling of the modified probe was successfully achieved with a radiochemical yield of over 99% and remained stable for 144 h. Cellular assays showed that the ligand concentration required for 50% inhibition of the probe was 1.20 ± 0.31 nM, and the Kd was 0.70 ± 0.07 nM with a Bmax of 7.94 ± 0.16 fmol/cell, indicative of higher specificity and affinity of DOTA-FAPI-maleimide compared to other FAPI-04 variants. In addition, DOTA-FAPI-maleimide exhibited a persistent blood clearance half-life of 7.11 ± 0.34 h. PET/CT images showed a tumor uptake of 2.20 ± 0.44%ID/g at 0.5 h p.i., with a tumor/muscle ratio of 5.64 in HT-1080-FAP tumor-bearing models. SPECT/CT images demonstrated long-lasting tumor retention. At 24 h p.i., the tumor uptake of [177Lu]Lu-DOTA-FAPI-maleimide reached 5.04 ± 1.67%ID/g, with stable tumor retention of 3.40 ± 1.95%ID/g after 4 days p.i. In conclusion, we developed and evaluated the thiol group-attaching strategy, which significantly extended the circulation and tumor retention of the adapted FAPI tracer. We envision its potential application for clinical cancer theranostics.

4.
Appl Radiat Isot ; 212: 111449, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39038403

ABSTRACT

A national Inter-Laboratory Comparisons (ILCs) programme was organized in Italy in 2022 by the Italian National Institute of Ionizing Radiation Metrology (INMRI), belonging to ENEA (Italian National Agency for New Technologies, Energy and Sustainable Economic Development), under the auspices of the Ministry of Enterprises and Made in Italy (Mimit ex MiSe). Within this ILCs programme, six inter-laboratory comparisons were organized, including the ILC-2 which focused on activity measurements carried out with radionuclide calibrators commonly used in the nuclear medicine departments of the participants. The focus was on three short-lived radionuclides - 99mTc, 18F, 177Lu - commonly employed in nuclear medicine for both diagnostic and therapeutic purposes. All presented results were compared with the reference values provided by ENEA-INMRI to ensure the traceability of measurements to the national primary activity standards. The observed deviation from the reference values of the measured activity were mainly within ± 10% (100% for 18F, 91.7% for 99mTc, 100% for 177Lu). The En statistical estimator was used to assess the participants' ability to estimate uncertainty in the provided activity values. The obtained values revealed that, in certain instances, the involved laboratories did not achieve the correct results for En (with failure rates of 22.7%, 16.7%, 12.5% for 18F, 99mTc, 177Lu, respectively), despite deviations from the reference values falling within the ± 10%. The aim of ILC-2 was to harmonize the activity measurements in the country within the field of nuclear medicine for the specific radionuclides studied and enhance the measurement capabilities of the participants.

5.
Article in English | MEDLINE | ID: mdl-39002946

ABSTRACT

INTRODUCTION: Patient safety is paramount in providing quality healthcare and constitutes a global concern for healthcare systems. Radioiodine treatment to patients with well-differentiated thyroid cancer is not without risks. The aim of this study is to identify, evaluate and mitigate the risks associated with this procedure. MATERIALS AND METHODS: A single-centre descriptive study was conducted in which risk management was carried out by establishing a risk map using FMEA methodology. RESULTS: Based on the process map 6 sub-processes and 23 failure modes in the three phases of the treatment process were analysed. According to risk priority number (RPN), the sub-process with the highest risk was administrative management (RPN 82), followed by treatment per se and post-treatment imaging (both with RPN 70). An overall process RPN of 300 (156 pre-treatment, 74 treatment and 70 post-treatment) was obtained. Failures directly related to the patient pose a high risk. The implementation of verification systems, performing tasks earlier and providing quality medical information are the most relevant preventive measures to be implemented. CONCLUSIONS: The application of the FMEA methodology in the risk management for radioiodine treatment is a valuable tool for improving the quality and safety of this process. The risk map has been able to identify failures at different stages, assess their causes and effects, prioritise the risks identified and implement preventive and corrective measures that can be monitored, ensuring the effectiveness of the actions taken.

6.
J Vet Intern Med ; 38(4): 2273-2281, 2024.
Article in English | MEDLINE | ID: mdl-39023205

ABSTRACT

BACKGROUND: The high doses of radioiodine-131 (131I) and, subsequently, the high radioactive burden for dog and environment warrants optimization of 131I therapy in dogs with thyroid carcinoma (TC). HYPOTHESIS/OBJECTIVES: To evaluate the effect of a revised protocol with recombinant human thyroid stimulating hormone (rhTSH) on tumor radioactive iodine uptake (RAIU) in dogs with TC. ANIMALS: Nine client-owned dogs diagnosed with TC. METHODS: A prospective cross-over study in which tumor RAIU was calculated and compared at 8 hours (8h-RAIU) and 24 hours (24h-RAIU) after injection of radioactive iodine-123 (123I), once with and once without rhTSH (ie, 250 µg, IM, 24 and 12 hours before 123I) in each dog. Simultaneously, serum total thyroxine (TT4) and TSH were measured at baseline (T0), and 6 (T6), 12 (T12), 24 (T24), and 48 hours (T48) after the first rhTSH administration. RESULTS: Tumor RAIU was significantly higher at 24 hours with rhTSH compared to no rhTSH (mean difference = 8.85%, 95% CI of [1.56; 16.14]; P = .03), while this was non-significant at 8 hours (mean difference = 4.54%, 95% CI of [0.35; 8.73]; P = .05). A significant change of serum TT4 (median difference T24 - T0 = 35.86 nmol/L, interquartile range [IQR] = 15.74 nmol/L) and TSH (median difference T24 - T0 = 1.20 ng/mL, IQR = 1.55 ng/mL) concentrations occurred after administration of rhTSH (P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Recombinant human TSH could optimize 131I treatment in dogs with TC by increasing tumor RAIU and thus 131I treatment efficacy.


Subject(s)
Cross-Over Studies , Dog Diseases , Iodine Radioisotopes , Recombinant Proteins , Thyroid Neoplasms , Thyrotropin , Animals , Dogs , Thyroid Neoplasms/veterinary , Thyroid Neoplasms/radiotherapy , Thyroid Neoplasms/drug therapy , Iodine Radioisotopes/therapeutic use , Dog Diseases/drug therapy , Dog Diseases/radiotherapy , Thyrotropin/therapeutic use , Thyrotropin/pharmacology , Female , Male , Prospective Studies , Recombinant Proteins/therapeutic use , Recombinant Proteins/pharmacology , Recombinant Proteins/administration & dosage , Thyroxine/therapeutic use
7.
J Biomed Phys Eng ; 14(3): 245-254, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39027715

ABSTRACT

Background: Nuclear medicine is an integral and developing field in diagnosing and treating diseases. Monitoring individuals' protection and radiation contamination in the workplace is vital for preserving working environments. Objective: This study aimed to monitor the nuclear medicine department's personnel, environment, and wastes to determine the level of occupational radiation and environmental pollution in Bushehr's nuclear medicine department. Material and Methods: In this cross-sectional study, the initial activity of each radioisotope, radiopharmaceutical, and radioactive waste was measured using a "well counter" daily for three months. Three irradiators' absorbed doses were measured using a direct reading dosimeter. The contamination was determined using an indirect wipe test method on various surfaces. A Geiger Müller dosimeter was employed to examine personnel's hands, clothing, and footwear. Results: The highest activity was observed in technetium waste (1118.31 mCi). Every irradiator received a lower absorption dose than the International Commission on Radiological Protection (ICRP) standard threshold. The majority of contamination was associated with the exercise test room (0.04 Bq/cm2) and its work surface (0.013 Bq/cm2), which were both below the threshold (0.5 Bq/cm2). Staff monitoring indicated that two nurses (10 and 11 individuals) had the highest contamination rate (23.7%). Conclusion: Daily assessment of the type, activity, and method of radiopharmaceutical administration to the patient is advantageous for waste management. Surface contamination monitoring can significantly contribute to the estimation of the level of radiation pollution in the environment.

8.
J Control Release ; 373: 265-276, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39019087

ABSTRACT

Curcumin potentiates the stabilization of atherosclerotic plaques by polarizing macrophages, but its non-specific targeting hinders its clinical application. We aim to harness multifunctional lipid nanoparticles (MLNPs) to facilitate the imaging and targeted delivery of curcumin specifically to inflammatory macrophages, counteracting vulnerable plaques and mitigating the risk of ischemic events. Cholesteryl-9-carboxynonanoate-(125I­iron oxide nanoparticle/Curcumin)-lipid-coated nanoparticles [9-CCN-(125I-ION/Cur)-LNPs], namely MLNPs, are designed to carry hybrid imaging agents. These agents combine 125I-ION with lipids containing phagocytic 'eat-me' signals, inducing macrophages to engulf the MLNPs. Our research demonstrates that the designed MLNPs accurately accumulate at unstable plaques and are precisely visualized and highlighted by both SPECT and MRI. Furthermore, MLNPs achieve high efficiency in delivering 125I-ION and curcumin to macrophages, ultimately leading to significant M1-to-M2 macrophage polarization. These real-time imaging and polarization capabilities of plaques have immediate clinical applicability and may pave the way for novel therapies to stabilize unstable atherosclerotic plaques.

9.
Jpn J Radiol ; 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39031270

ABSTRACT

PURPOSE: The performance of vision-language models (VLMs) with image interpretation capabilities, such as GPT-4 omni (GPT-4o), GPT-4 vision (GPT-4V), and Claude-3, has not been compared and remains unexplored in specialized radiological fields, including nuclear medicine and interventional radiology. This study aimed to evaluate and compare the diagnostic accuracy of various VLMs, including GPT-4 + GPT-4V, GPT-4o, Claude-3 Sonnet, and Claude-3 Opus, using Japanese diagnostic radiology, nuclear medicine, and interventional radiology (JDR, JNM, and JIR, respectively) board certification tests. MATERIALS AND METHODS: In total, 383 questions from the JDR test (358 images), 300 from the JNM test (92 images), and 322 from the JIR test (96 images) from 2019 to 2023 were consecutively collected. The accuracy rates of the GPT-4 + GPT-4V, GPT-4o, Claude-3 Sonnet, and Claude-3 Opus were calculated for all questions or questions with images. The accuracy rates of the VLMs were compared using McNemar's test. RESULTS: GPT-4o demonstrated the highest accuracy rates across all evaluations with the JDR (all questions, 49%; questions with images, 48%), JNM (all questions, 64%; questions with images, 59%), and JIR tests (all questions, 43%; questions with images, 34%), followed by Claude-3 Opus with the JDR (all questions, 40%; questions with images, 38%), JNM (all questions, 42%; questions with images, 43%), and JIR tests (all questions, 40%; questions with images, 30%). For all questions, McNemar's test showed that GPT-4o significantly outperformed the other VLMs (all P < 0.007), except for Claude-3 Opus in the JIR test. For questions with images, GPT-4o outperformed the other VLMs in the JDR and JNM tests (all P < 0.001), except Claude-3 Opus in the JNM test. CONCLUSION: The GPT-4o had the highest success rates for questions with images and all questions from the JDR, JNM, and JIR board certification tests.

11.
Diagnostics (Basel) ; 14(12)2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38928655

ABSTRACT

PURPOSE: The purpose of this study is to examine the feasibility of a machine learning (ML) system for optimizing a gastric emptying scintigraphy (GES) protocol for the detection of delayed gastric emptying (GE), which is considered a primary indication for the diagnosis of gastroparesis. METHODS: An ML model was developed using the JADBio AutoML artificial intelligence (AI) platform. This model employs the percent GE at various imaging time points following the ingestion of a standardized radiolabeled meal to predict normal versus delayed GE at the conclusion of the 4 h GES study. The model was trained and tested on a cohort of 1002 patients who underwent GES using a 70/30 stratified split ratio for training vs. testing. The ML software automated the generation of optimal predictive models by employing a combination of data preprocessing, appropriate feature selection, and predictive modeling analysis algorithms. RESULTS: The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was employed to evaluate the predictive modeling performance. Several models were developed using different combinations of imaging time points as input features and methodologies to achieve optimal output. By using GE values at time points 0.5 h, 1 h, 1.5 h, 2 h, and 2.5 h as input predictors of the 4 h outcome, the analysis produced an AUC of 90.7% and a balanced accuracy (BA) of 80.0% on the test set. This performance was comparable to the training set results (AUC = 91.5%, BA = 84.7%) within the 95% confidence interval (CI), demonstrating a robust predictive capability. Through feature selection, it was discovered that the 2.5 h GE value alone was statistically significant enough to predict the 4 h outcome independently, with a slightly increased test set performance (AUC = 92.4%, BA = 83.3%), thus emphasizing its dominance as the primary predictor for delayed GE. ROC analysis was also performed for single time imaging points at 1 h and 2 h to assess their independent predictiveness of the 4 h outcome. Furthermore, the ML model was tested for its ability to predict "flipping" cases with normal GE at 1 h and 2 h that became abnormal with delayed GE at 4 h. CONCLUSIONS: An AI/ML model was designed and trained for predicting delayed GE using a limited number of imaging time points in a 4 h GES clinical protocol. This study demonstrates the feasibility of employing ML for GES optimization in the detection of delayed GE and potentially shortening the protocol's time length without compromising diagnostic power.

12.
Life (Basel) ; 14(6)2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38929734

ABSTRACT

Rheumatoid arthritis (RA) is a systemic autoimmune disorder caused by inflammation of cartilaginous diarthrodial joints that destroys joints and cartilage, resulting in synovitis and pannus formation. Timely detection and effective management of RA are pivotal for mitigating inflammatory arthritis consequences, potentially influencing disease progression. Nuclear medicine using radiolabeled targeted vectors presents a promising avenue for RA diagnosis and response to treatment assessment. Radiopharmaceutical such as technetium-99m (99mTc), combined with single photon emission computed tomography (SPECT) combined with CT (SPECT/CT), introduces a more refined diagnostic approach, enhancing accuracy through precise anatomical localization, representing a notable advancement in hybrid molecular imaging for RA evaluation. This comprehensive review discusses existing research, encompassing in vitro, in vivo, and clinical studies to explore the application of 99mTc radiolabeled targeting vectors with SPECT imaging for RA diagnosis. The purpose of this review is to highlight the potential of this strategy to enhance patient outcomes by improving the early detection and management of RA.

13.
Pharmaceuticals (Basel) ; 17(6)2024 May 31.
Article in English | MEDLINE | ID: mdl-38931383

ABSTRACT

The role of fibroblast activation protein inhibitor (FAPI) positron emission tomography/computed tomography (PET/CT) is emerging for the assessment of non-oncological diseases, such as inflammatory and infectious diseases, even if the evidence in the literature is still in its initial phases. We conducted a systematic search of Scopus, PubMed/MEDLINE, Embase, and Cochrane library databases for studies published before 31 December 2023 reporting infectious and inflammatory disease imaging with FAPI PET/CT. We included twenty-one studies for a total of 1046 patients. The most frequent disease studied was lung interstitial disease, investigated in six studies for a total of 200 patients, followed by bone and joint diseases in two studies and 185 patients, IgG4-related disease in 53 patients, and Crohn's disease in 30 patients. Despite the heterogeneity of studies in terms of study design and technical features, FAPI PET/CT showed a high detection rate and diagnostic role. Moreover, when compared with 2-[18F]FDG PET/CT (n = 7 studies), FAPI PET/CT seems to have better diagnostic performances. The presence of chronic inflammation and tissue remodeling, typical of immune-mediated inflammatory conditions, may be the underlying mechanism of FAPI uptake.

14.
World J Nucl Med ; 23(2): 73-78, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38933075

ABSTRACT

Objective Our objective was to investigate the basic information of the personnel and facilities of nuclear medicine in Beijing. Methods This survey was performed by the Beijing Quality Control Center in 2018. The investigation included personnel, equipment, and clinical applications, and data were then compared with previous surveys. The paper questionnaires were used for the survey, which required information about the personnel, devices, and clinical applications. Results About 38 nuclear medicine departments in Beijing were involved in the survey. The number of nuclear medicine staff was 531 in 2018, showing an increase of 58.7% over the past decade. Positron emission tomography/computed tomography (PET/CT), single-photon emission computed tomography (SPECT), and single-photon emission computed tomography/computed tomography (SPECT/CT) represented the main nuclear medicine facilities, and the total number of surveyed departments was 18, 24, and 34, respectively. The quality control results showed significant improvement from the 2005 levels. The total number of scintigraphy procedures was estimated at 199,607 (153,185 SPECT and 46,422 PET/CT). The estimated annual number of scintigraphy images was 8.9 per 1,000 population for SPECT and 2.7 per 1,000 population for PET/CT during 2018. The most frequent radioiodine-targeted therapy was 131 I-targeted therapy for hyperthyroidism in 2018. Conclusion Nuclear medicine has experienced rapid growth in the past 10 years in Beijing, either in personnel, equipment, and scintigraphy. Future efforts will focus on the use of new isotopes in the diagnosis, implementing quality strategy, and enhancing training.

15.
Echocardiography ; 41(7): e15854, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38940225

ABSTRACT

Coronary artery disease (CAD) is a prevalent cause of left ventricular dysfunction. Nevertheless, effective elective revascularization, particularly surgical revascularization, can enhance long-term outcomes and, in selected cases, global left ventricular contractility. The assessment of myocardial viability and scars is still relevant in guiding treatment decisions and selecting patients who are likely to benefit most from blood flow restoration. Although the most recent randomized studies challenge the notion of "hibernating myocardium" and the clinical usefulness of assessing myocardial viability, the advancement of imaging techniques still renders this assessment valuable in specific situations. According to the guidelines of the European Society of Cardiology, non-invasive stress imaging may be employed to define myocardial ischemia and viability in patients with CAD and heart failure before revascularization. Currently, several non-invasive imaging techniques are available to evaluate the presence and extent of viable myocardium. The selection of the most suitable technique should be based on the patient, clinical context, and resource availability. This narrative review evaluates the characteristics of available imaging modalities for assessing myocardial viability to determine the most appropriate therapeutic strategy.


Subject(s)
Coronary Artery Disease , Humans , Coronary Artery Disease/physiopathology , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/diagnosis , Coronary Artery Disease/complications , Multimodal Imaging/methods , Myocardium/pathology , Echocardiography/methods , Tissue Survival
16.
Expert Rev Endocrinol Metab ; 19(4): 349-366, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38836602

ABSTRACT

INTRODUCTION: Neuroendocrine neoplasms (NENs) represent a complex group of tumors arising from neuroendocrine cells, characterized by heterogeneous behavior and challenging diagnostics. Despite advancements in medical technology, NENs present a major challenge in early detection, often leading to delayed diagnosis and variable outcomes. This review aims to provide an in-depth analysis of current diagnostic methods as well as the evolving and future directions of diagnostic strategies for NENs. AREA COVERED: The review extensively covers the evolution of diagnostic tools for NENs, from traditional imaging and biochemical tests to advanced genomic profiling and next-generation sequencing. The emerging role of technologies such as artificial intelligence, machine learning, and liquid biopsies could improve diagnostic precision, as could the integration of imaging modalities such as positron emission tomography (PET)/magnetic resonance imaging (MRI) hybrids and innovative radiotracers. EXPERT OPINION: Despite progress, there is still a significant gap in the early diagnosis of NENs. Bridging this diagnostic gap and integrating advanced technologies and precision medicine are crucial to improving patient outcomes. However, challenges such as low clinical awareness, limited possibility of noninvasive diagnostic tools and funding limitations for rare diseases like NENs are acknowledged.


Subject(s)
Neuroendocrine Tumors , Humans , Neuroendocrine Tumors/diagnosis , Neuroendocrine Tumors/genetics , Neuroendocrine Tumors/diagnostic imaging , Positron-Emission Tomography , Early Detection of Cancer/methods , Precision Medicine , Magnetic Resonance Imaging/methods , High-Throughput Nucleotide Sequencing , Artificial Intelligence
17.
Mol Pharm ; 21(7): 3383-3394, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38831541

ABSTRACT

Carbonic anhydrase IX (CAIX), a zinc metal transmembrane protein, is highly expressed in 95% of clear cell renal cell carcinomas (ccRCCs). A positron emission tomography (PET) probe designed to target CAIX in nuclear medicine imaging technology can achieve precise positioning, is noninvasive, and can be used to monitor CAIX expression in lesions in real time. In this study, we constructed a novel acetazolamide dual-targeted small-molecule probe [68Ga]Ga-LF-4, which targets CAIX by binding to a specific amino acid sequence. After attenuation correction, the radiolabeling yield reached 66.95 ± 0.57% (n = 5) after 15 min of reaction and the radiochemical purity reached 99% (n = 5). [68Ga]Ga-LF-4 has good in vitro and in vivo stability, and in vivo safety and high affinity for CAIX, with a Kd value of 6.62 nM. Moreover, [68Ga]Ga-LF-4 could be quickly cleared from the blood in vivo. The biodistribution study revealed that the [68Ga]Ga-LF-4 signal was concentrated in the heart, lung, and kidney after administration, which was the same as that observed in the micro-PET/CT study. In a ccRCC patient-derived xenograft (PDX) model, the signal significantly accumulated in the tumor after administration, where it was retained for up to 4 h. After competitive blockade with LF-4, uptake at the tumor site was significantly reduced. The SUVmax of the probe [68Ga]Ga-LF-4 at the ccRCC tumor site was three times greater than that in the PC3 group with low CAIX expression at 30 min (ccRCC vs PC3:1.86 ± 0.03 vs 0.62 ± 0.01, t = 48.2, P < 0.0001). These results indicate that [68Ga]Ga-LF-4 is a novel small-molecule probe that targets CAIX and can be used to image localized and metastatic ccRCC lesions.


Subject(s)
Carbonic Anhydrase IX , Carcinoma, Renal Cell , Gallium Radioisotopes , Kidney Neoplasms , Animals , Carbonic Anhydrase IX/metabolism , Carbonic Anhydrase IX/antagonists & inhibitors , Humans , Mice , Carcinoma, Renal Cell/diagnostic imaging , Carcinoma, Renal Cell/metabolism , Kidney Neoplasms/diagnostic imaging , Kidney Neoplasms/metabolism , Tissue Distribution , Cell Line, Tumor , Radiopharmaceuticals/pharmacokinetics , Radiopharmaceuticals/chemistry , Mice, Nude , Antigens, Neoplasm/metabolism , Molecular Probes/pharmacokinetics , Molecular Probes/chemistry , Positron Emission Tomography Computed Tomography/methods , Acetazolamide/pharmacokinetics , Female , Mice, Inbred BALB C , Positron-Emission Tomography/methods , Male , Xenograft Model Antitumor Assays
18.
Cureus ; 16(5): e60656, 2024 May.
Article in English | MEDLINE | ID: mdl-38899261

ABSTRACT

PURPOSE: Motion artifacts caused by heart motion during myocardial perfusion single-photon emission computed tomography (SPECT) can compromise image quality and diagnostic accuracy. This study aimed to evaluate the efficacy of the novel respiratory motion reduction block (RRB) device in reducing motion artifacts by compressing the hypochondrium and improving SPECT image quality. METHODS: In total, 91 patients who underwent myocardial perfusion SPECT with 99mTc-sestamibi were retrospectively analyzed. Patients (n = 28) who underwent SPECT without the RRB were included in the control group, and those (n = 63) who underwent SPECT with the RRB were in the RRB group. The distance of heart motion during dynamic acquisition was measured, and projection data were assessed for patient motion and motion artifacts. Patient motion was classified into various levels, and motion artifacts on SPECT images were visually examined. RESULTS: The distances of heart motion without and with the RRB were 15.4 ± 5.3 and 7.5 ± 2.3, respectively. Compared with the control group, the RRB group had a lower frequency of heart motion based on the projection data, particularly in terms of creep and shift motion. The RRB group had a significantly lower incidence of motion artifacts on SPECT images than the control group. CONCLUSIONS: The RRB substantially reduced specific types of motion, such as shift and creep, and had a low influence on bounce motion. However, it could effectively suppress respiratory-induced heart motion and reduce motion artifacts on myocardial perfusion SPECT, thereby emphasizing its potential for improving image quality.

19.
BMJ Open ; 14(6): e081401, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38908839

ABSTRACT

INTRODUCTION: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs), currently marketed for type 2 diabetes and obesity, may offer novel mechanisms to delay or prevent neurotoxicity associated with Alzheimer's disease (AD). The impact of semaglutide in amyloid positivity (ISAP) trial is investigating whether the GLP-1 RA semaglutide reduces accumulation in the brain of cortical tau protein and neuroinflammation in individuals with preclinical/prodromal AD. METHODS AND ANALYSIS: ISAP is an investigator-led, randomised, double-blind, superiority trial of oral semaglutide compared with placebo. Up to 88 individuals aged ≥55 years with brain amyloid positivity as assessed by positron emission tomography (PET) or cerebrospinal fluid, and no or mild cognitive impairment, will be randomised. People with the low-affinity binding variant of the rs6971 allele of the Translocator Protein 18 kDa (TSPO) gene, which can interfere with interpreting TSPO PET scans (a measure of neuroinflammation), will be excluded.At baseline, participants undergo tau, TSPO PET and MRI scanning, and provide data on physical activity and cognition. Eligible individuals are randomised in a 1:1 ratio to once-daily oral semaglutide or placebo, starting at 3 mg and up-titrating to 14 mg over 8 weeks. They will attend safety visits and provide blood samples to measure AD biomarkers at weeks 4, 8, 26 and 39. All cognitive assessments are repeated at week 26. The last study visit will be at week 52, when all baseline measurements will be repeated. The primary end point is the 1-year change in tau PET signal. ETHICS AND DISSEMINATION: The study was approved by the West Midlands-Edgbaston Research Ethics Committee (22/WM/0013). The results of the study will be disseminated through scientific presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: ISRCTN71283871.


Subject(s)
Alzheimer Disease , Glucagon-Like Peptides , Positron-Emission Tomography , Humans , Glucagon-Like Peptides/administration & dosage , Glucagon-Like Peptides/therapeutic use , Double-Blind Method , Alzheimer Disease/drug therapy , Positron-Emission Tomography/methods , United Kingdom , Administration, Oral , Male , Middle Aged , Female , tau Proteins , Aged , Brain/diagnostic imaging , Brain/metabolism , Brain/drug effects , Randomized Controlled Trials as Topic
20.
J Med Imaging Radiat Sci ; 55(3): 101437, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38879924

ABSTRACT

BACKGROUND: Simulation based learning provides an opportunity to increase student readiness prior to clinical placement. Cross disciplinary learning facilitates interprofessional competency building and improved student appreciation of other health professions, which adds another learning dimension to simulated scenarios. This paper outlines the approach to facilitating an interdisciplinary simulated clinic, where experiences were mapped to common professional capabilities. METHODS: After mapping skill sets and professional capabilities common to both Nuclear Medicine and Radiation Therapy, a mock clinic was planned to address common objectives. The aims of the activity were to prepare students for upcoming clinical placement and to build knowledge and skills in the interprofessional environment. All students were allocated roles of both the health care professional and the patient and introduced to the concept of interprofessional learning in a pre-brief session. During the simulated clinic phase students experienced the other modality through the patient perspective as well as practicing the clinician role within their own modality. Following the simulation students came together for a de-brief session. The activity was evaluated using both online polling and pre and post paper-based surveys. RESULTS: A total of 28 students participated in the simulation: 17 in radiation therapy and 11 in nuclear medicine. All participants agreed that the mock clinic was valuable preparation for clinical placement. Twenty-four completed pre and post surveys, revealed a collective improvement in several measures of interprofessional understanding and application. Free text polled responses in the de-brief session highlighted value for practicing communication, realistic physical resemblance to the real-life scenarios and time pressures. CONCLUSION: When two disciplines were combined in the simulated clinic, students learnt about each other's profession together. Evaluation showed positive improvements in both clinical readiness and interprofessional learning. Simulated tasks in healthcare education bought many benefits in preparing students for the workplace and in this example, enabled common objectives of interprofessional practice to be met.

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