Molecular Imaging and Biology最新文献

{"title":"Preclinical Evaluation of [¹⁸F]JNJ-1: A Novel Positron Emission Tomography Ligand Targeting AMPAR/TARP γ8.","authors":"Chunfang A Xia, Wei Zhang, Tamara Berdyyeva, Chaofeng Huang, Michael K Ameriks, Terry P Lebold, Michael P Maher, Cristian C Constantinescu, Leslie Nguyen, Nyantsz Wu, Gang Chen, Hartmuth C Kolb, Anna Katrin Szardenings","doi":"10.1007/s11307-026-02112-w","DOIUrl":"https://doi.org/10.1007/s11307-026-02112-w","url":null,"abstract":"<p><strong>Purpose: </strong>The AMPA receptor (AMPARs) mediates fast excitatory neurotransmission and is the central to synaptic plasticity, learning and memory dysregulation of this system has been implicated in epilepsy, neurodegeneration, and neuropsychiatric disorders. The transmembrane AMPA receptor regulatory protein γ8 (TARP γ8) plays a crucial role in the expression and localization of AMPARs within the brain, particularly in the hippocampus and cortex. A selective positron emission tomography (PET) ligand to image this target is of significant interest for investigating potential clinical AMPAR/TARP γ8 antagonists. This study describes the development and preclinical evaluation of a potent and selective tracer targeting TARP γ8, [¹⁸F]JNJ-1.</p><p><strong>Procedures: </strong>The binding potency of JNJ-1 was evaluated using a calcium flux assay in HEK-293 cells. The radiotracer was synthesized on an automated synthesizer via a one-step substitution. TARP γ8 target expression in brains was confirmed through immunohistochemistry (IHC), and adjacent brain sections were used for autoradiography (ARG). In vivo assays were conducted in rats, knockout mice, and non-human primates by [¹⁸F]JNJ-1 PET imaging and JNJ-1 microdosing studies.</p><p><strong>Results: </strong>JNJ-1 exhibited very high binding potency to TARP γ8, IC₅₀ = 50 pM. Immunoreactivity of TARP γ8 showed high intensity in the hippocampus and moderate levels in the cortex across mouse, rat, and monkey brains. A microdosing with JNJ-1 study revealed high, moderate, and low levels of JNJ-1 uptake in the hippocampus, cortex, and cerebellum, respectively in wild-type mice (γ8 + / +), and low levels in all regions in knockout (γ8 - / -) mouse brains. In vitro ARG of [¹⁸F]JNJ-1 corresponded with IHC staining on adjacent rat brain sections, and the signal being blocked by JNJ-2, a potent and selective antagonist of TARP γ8. In vivo PET imaging demonstrated high brain uptake in the expected areas in rats and monkeys, which was blockable by JNJ-2 in a dose-dependent manner.</p><p><strong>Conclusion: </strong>[¹⁸F]JNJ-1 is emerging as a promising PET tracer with high in vitro binding affinity and evidence suggestive of target engagement at AMPAR/TARP γ8. The process of clinical validation is presently underway.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148258792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probing Early Myocardial Remodeling in Response to a High-Fat Diet in Mice by Evaluation of Extracellular Volume Fraction Using 4D Retrospectively Gated Micro-CT Imaging.","authors":"Grzegorz Kwiatkowski, Anna Gąsiorek, Izabela Ciastoń, Joanna Kozieł, Greetje Vande Velde, Stefan Chłopicki","doi":"10.1007/s11307-026-02111-x","DOIUrl":"https://doi.org/10.1007/s11307-026-02111-x","url":null,"abstract":"<p><strong>Purpose: </strong>The objective of this study was to evaluate whether retrospectively gated 4D micro-computed tomography (µCT) can quantify extracellular volume fraction (ECV) as an early marker of myocardial fibrosis and remodeling in a high-fat diet (HFD) mouse model, and to determine its relationship with cardiac functional parameters.</p><p><strong>Procedures: </strong>Male C57BL/6J mice were assigned to control diet or high-fat diet (HFD) groups, with HFD animals imaged after 8 or 16 weeks of feeding and control animals scanned at an age-matched time point. Contrast-enhanced 4D µCT with ECG gating was performed for cardiac function analysis and pre/post-contrast imaging for ECV quantification, corrected for hematocrit. Functional measures included left ventricular (LV) volumes, ejection fraction, mitral annular plane systolic excursion (MAPSE), circumferential shortening, and dobutamine stress response.</p><p><strong>Results: </strong>Global LV ECV significantly increased at 8 weeks of HFD compared to controls, preceding changes in LV mass and ejection fraction. Early ECV elevation correlated with impaired lateral MAPSE, indicating subtle functional impairment despite preserved global systolic function. At 16 weeks, further remodeling was evident with increased LV mass, reduced epicardial circumferential shortening, decreased left atrial ejection area, and diminished dobutamine-induced contractile reserve.</p><p><strong>Conclusions: </strong>Retrospectively gated 4D µCT provides a robust and noninvasive method for early detection of diffuse myocardial fibrosis and functional impairment in small animal models. This approach enables longitudinal studies of cardiac disease progression and therapeutic interventions, offering translational value for preclinical cardiology research.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148226293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation and Correction of the Partial Volume Effect Using Personalized Phantoms of Lymph Node Metastases in Lutetium 177 SPECT/CT Dosimetry.","authors":"J R Hinz, T Kuwert, M Beck, P Ritt, A Grings","doi":"10.1007/s11307-026-02103-x","DOIUrl":"10.1007/s11307-026-02103-x","url":null,"abstract":"<p><strong>Purpose: </strong>This study aims to quantify and to correct for partial volume effect (PVE) in lymph node metastases of prostate cancer (PC) on Lu-177 SPECT images using 3D-printed phantoms of these structures to establish a ground truth.</p><p><strong>Procedures: </strong>Ten individuals with clearly delineated, SPECT-positive lymph node metastases were retrospectively selected from a cohort of PC patients undergoing radioligand therapy (RLT). Manual segmentation of the metastases was performed on the CT component. The segmented lymph nodes were 3D-printed as patient-specific lymph node phantoms with volumes ranging from 0.18 to 23.7 ml using a high-resolution 3D printer. These phantoms were filled with Lu-177 and analyzed in a SPECT/CT system to quantify PVE. An exponential curve fit of the recovery coefficient (RC) versus the surface-area to volume ratio (SA:V) was derived from the spheres of a NEMA ICE body phantom and used to correct for PVE in the lymph node phantoms. This method was compared with other post-reconstruction partial volume corrections (PVC).</p><p><strong>Results: </strong>For a tumor to background ratio (TBR) of 10:1 the RCs varied widely, from 82% to 10.4% depending on phantom size. Using the NEMA IEC body phantom, an exponential correlation was established between SA:V and RC, with R² values exceeding 0.97 across measurements at four different TBRs. Using this curve for PVE correction, the RCs of the lymph node phantoms had an average deviation from the ground truth of 1.15 ± 10.15% (average ± standard error of the mean). This method had a higher accuracy than the other PVCs studied.</p><p><strong>Conclusions: </strong>The low RCs obtained for lymph node metastases suggest that Lu-177-dosimetry is in these structures grossly inaccurate without PVE correction. Applying the SA:V/RC curve established using the NEMA IEC body phantom for this purpose reduces PVE-related errors considerably.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":"470-480"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13337594/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147776457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual Quantification of Skeletal Muscle Perfusion and Metabolism in a Porcine Model of Peripheral Artery Disease Using Multiparametric ¹⁸F-FDG PET Imaging.","authors":"Ting-Heng Chou, Mahboubeh Nabavinia, Eleanor T Rimmerman, Corrin Mansfield, Kumudha Narayana Musini, Nguyen K Tram, Mitchel R Stacy","doi":"10.1007/s11307-026-02106-8","DOIUrl":"10.1007/s11307-026-02106-8","url":null,"abstract":"<p><strong>Background: </strong>A standard imaging strategy for quantifying skeletal muscle perfusion in peripheral artery disease (PAD) does not exist, and the widespread use of PET imaging for this purpose has traditionally been limited by the need for onsite production of short half-life perfusion radioisotopes. Therefore, this study investigated the feasibility of multiparametric PET imaging with commercially available fluorine-18 (¹⁸F)-fluorodeoxyglucose (FDG) for the quantification of skeletal muscle perfusion and metabolism in a porcine model of PAD.</p><p><strong>Methods: </strong>Eight Yorkshire pigs underwent 60-min dynamic ¹⁸F-FDG PET imaging under resting conditions immediately following unilateral surgical ligation of the femoral artery and 2 weeks after arterial occlusion. Calf muscle perfusion was computed using 1-compartment modeling of the first 2.5 min of PET data acquisition, and the metabolic rate of glucose (MRGlu) was computed using 3-compartment modeling of the entire 60-min dataset. Two weeks after arterial occlusion, the gastrocnemius muscle was harvested to compare microvascular density between ischemic and control hindlimbs.</p><p><strong>Results: </strong>Calf perfusion and MRGlu were significantly reduced following peripheral artery occlusion and recovered to control levels 2 weeks later. Recovery of perfusion and metabolism in calf skeletal muscle coincided with a significant increase in calf muscle capillary density 2 weeks after arterial occlusion.</p><p><strong>Conclusions: </strong>This study demonstrates the novel use of dynamic, multiparametric ¹⁸F-FDG PET/CT imaging for quantifying ischemia-induced alterations in skeletal muscle perfusion and metabolism, providing a unique comprehensive approach for evaluating PAD pathophysiology and creating opportunities for monitoring treatment responses to emerging therapeutics.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":"449-456"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13337911/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147817645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of [¹⁸F]DPA-814 with [¹⁸F]DPA-714 for TSPO Imaging in an Experimental Model.","authors":"J van der Bie, J Bakker, E J Verschoor, E Nutma, J Middeldorp, W Beaino, M Kassiou, J J Danon, J A M Langermans, A D Windhorst, M A Stammes","doi":"10.1007/s11307-026-02094-9","DOIUrl":"10.1007/s11307-026-02094-9","url":null,"abstract":"<p><strong>Purpose: </strong>[¹⁸F]DPA-714 is a valuable tracer for studying (neuro)inflammation, with well-characterized tracer kinetics and an established imaging window. However, its clinical utility is restricted by the TSPO polymorphism (rs6971), which influences binding affinity in humans. The newly developed tracer [¹⁸F]DPA-814 overcomes this limitation and has shown promising results in a preclinical rat model. To further assess its clinical potential, we compared [¹⁸F]DPA-814 to [¹⁸F]DPA-714 for inflammation imaging in SARS-CoV-2-infected macaques in a longitudinal setting.</p><p><strong>Procedures: </strong>Dynamic positron emission tomography (PET) imaging was conducted in four healthy macaques to identify the optimal imaging window for [¹⁸F]DPA-814. Four additional macaques were infected with SARS-CoV-2 and monitored for 12 months using whole-body PET-computed tomography (CT) with both tracers. Baseline scans were compared to PET-CTs obtained at 4, 9 and 16 days and at 6 and 12 months post-infection, covering the head, thorax and abdomen. Tracer uptake was assessed in several organs.</p><p><strong>Results: </strong>At baseline, [¹⁸F]DPA-814 showed higher lung uptake with minimal washout compared to [¹⁸F]DPA-714. Although lung lesions developed after infection, [¹⁸F]DPA-814 did not demonstrate lesion-specific uptake, unlike [¹⁸F]DPA-714. In the brain, the tracers also displayed divergent uptake patterns despite comparable TSPO levels across animals and regions.</p><p><strong>Conclusions: </strong>[¹⁸F]DPA-814 exhibits a distinct whole-body distribution, particularly in the lungs and brain, in both naïve and SARS-CoV-2-infected macaques compared with [¹⁸F]DPA-714, likely reflecting differences in tracer kinetics. Based on these data, [¹⁸F]DPA-814 may not fully replace [¹⁸F]DPA-714 for lung and brain imaging, and further studies are required to evaluate its suitability in other anatomical regions.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":"502-512"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13337680/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147593200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative [¹⁸F]PSMA-1007 PET in Treatment Response Monitoring of Brain Metastases from Non-small Cell Lung Cancer.","authors":"Elisabeth Kirkeby Lysvik, Andreas Julius Tulipan, Vilde Drageset Haakensen, Mona-Elisabeth R Revheim, Kyrre Eeg Emblem, Trine Hjørnevik","doi":"10.1007/s11307-026-02104-w","DOIUrl":"10.1007/s11307-026-02104-w","url":null,"abstract":"<p><strong>Purpose: </strong>Prostate-specific membrane antigen (PSMA) is expressed in several solid tumours, including brain metastases (BMs) from lung cancer. We investigated quantitative [¹⁸F]PSMA-1007 uptake and treatment response in BMs of patients with non-small cell lung cancer (NSCLC).</p><p><strong>Procedures: </strong>Eleven patients with BM of NSCLC underwent 95-min dual-time-point dynamic [¹⁸F]PSMA-1007 PET/CT and a whole-body static scan before and after stereotactic radiosurgery (SRS) with a median dose of 20 Gy (range: 8-25 Gy) given in a median of 1 fraction (range: 1-3). Seven patients completed both exams. Image-derived input functions were extracted from the internal carotid arteries, and pharmacokinetic analysis using Patlak modelling yielded the influx constant (K_i). Standardised uptake value (SUV), biological tumour volume (BTV) and tumour heterogeneity using the coefficient of variance (CoV) were assessed.</p><p><strong>Results: </strong>[¹⁸F]PSMA-1007 PET showed uptake in the first exam in BMs and primary lung tumour in all patients. Significant inter-patient and intra-lesion heterogeneity in tracer uptake was observed in BMs with median Ki of 0.005 ml/ccm/min (range: 0.003-0.018 ml/ccm/min), SUV_peak of 4.2 g/ml (range: 0.4-34.4 g/ml), CoV of 0.36 (range 0.06-0.85) and BTV of 2.35 ml (range 0.03-22.29 ml). After SRS, reductions in K_i (37%), SUV_peak (50%), CoV (24%) and BTV (71%) were noted. Median SUV_peak in the lungs were 6.1 g/ml (range: 3.2-13.6 g/ml) at the initial exam and 6.3 g/ml (range: 3.8-11.8 g/ml) at the second exam.</p><p><strong>Conclusion: </strong>[¹⁸F]PSMA-1007 PET is a promising diagnostic tool for BMs from NSCLC. The uptake and heterogeneity, along with the marked reduction post-therapy, highlights its potential for monitoring treatment response.</p><p><strong>Trial registration: </strong>Clinicaltrials.gov, NCT03951142. Registered 5 October 2019, https://clinicaltrials.gov/ct2/show/NCT03951142 . EudraCT no 2018-003229-27. Registered 26 February 2019, https://www.clinicaltrialsregister.eu/ctr-search/trial/2018-003229-27/NO .</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":"438-448"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13337793/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147776469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Optimized Fast Track Protocol to Enhance the Image Quality of 18F-FDG PET Myocardial Viability Imaging in Diabetic CAD Patients: A Randomized Controlled Trial.","authors":"Alok Mandal, Sameer Taywade, Vijayaraghavan R L, Althaf Majeed, Onjal Taywade, Rajesh Kumar","doi":"10.1007/s11307-025-02074-5","DOIUrl":"10.1007/s11307-025-02074-5","url":null,"abstract":"<p><strong>Background: </strong>Standard ASNC guidelines for 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) myocardial viability imaging often yield suboptimal image quality in patients with diabetes mellitus, primarily due to altered glucose-insulin kinetics. This study evaluated an optimized fast-track (OFT) patient preparation protocol designed to improve image quality and reduce preparation time in diabetic patients with coronary artery disease (CAD).</p><p><strong>Methods: </strong>We conducted a prospective, randomized controlled trial involving 50 diabetic patients with known CAD. Patients were stratified based on diabetes duration, fasting blood sugar (FBS), and HbA1C levels, then assigned to either a standard preparation group or the OFT protocol group prior to undergoing 18F-FDG PET imaging. Image quality was assessed qualitatively using a visual grading scale and semi-quantitatively using the myocardium-to-blood pool (M/B) standardized uptake value ratio. Patient preparation time (PPT) was measured from oral glucose administration to 18F-FDG injection.</p><p><strong>Results: </strong>The OFT group demonstrated a higher proportion of interpretable scans (92% vs 64%; p = 0.017) and significantly greater M/B ratios (mean ± SD: 12.44 ± 5.37 vs 7.23 ± 3.42; p < 0.001) compared to the standard group. Median PPT was also significantly shorter in the OFT group (82 min) than in the standard group (95 min; p = 0.003).</p><p><strong>Conclusions: </strong>The optimized fast-track protocol significantly improves image quality and reduces patient preparation time in diabetic individuals undergoing 18F-FDG PET myocardial viability imaging. This protocol offers a practical and effective alternative to the standard ASNC approach, with potential for integration into routine clinical practice.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":"481-489"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147691173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Astrocyte Activation Persists after Recovery of Myelin and Motor Deficits in the Cuprizone Model: a Longitudinal PET and CNS Tissue Analysis Study.","authors":"V Pegoretti, A S Boerema, J W A Sijbesma, L E R Dietz, N Alberts, W Douwenga, U L M Eisel, E F J de Vries","doi":"10.1007/s11307-026-02098-5","DOIUrl":"10.1007/s11307-026-02098-5","url":null,"abstract":"<p><strong>Purpose: </strong>The cuprizone (CPZ) mouse model for multiple sclerosis enables researchers to investigate the underlying mechanisms of demyelination and remyelination, as well as the effect of therapeutic interventions thereon. Over the last five decades, research revealed detailed analyses of brain tissue derived from CPZ-fed animals at different times of de- and re-myelination. Yet, longitudinal analysis of the effects of a CPZ diet on locomotor performance, myelination and neuroinflammation over a two-month recovery period are still unexplored.</p><p><strong>Procedures: </strong>In this study, we comprehensively examined behavioural and neuropathological changes in the CPZ mouse model for a follow-up period of two months. We combined a longitudinal PET imaging approach with a more traditional approach of obtaining tissue and performing immunohistochemistry and behavioural tests in cohorts.</p><p><strong>Results: </strong>We found that mice fed with 0.2% CPZ for 5 weeks showed transient motor deficits which recovered quickly after cuprizone was removed from the diet. Similarly, remyelination also promptly restored myelin content after CPZ toxic insult, as seen by PET imaging with [¹¹C]MeDAS and myelin histological staining. Remarkably, five weeks of CPZ feeding led to persistent glial activation, especially in the corpus callosum, for at least two months. This effect was measured both with [¹¹C]PK11195 PET and with immunohistochemical staining for microglia and astrocytes.</p><p><strong>Conclusions: </strong>Taken together, this longitudinal study reveals that a five-week CPZ diet leads to transient motor and loss of myelin, which recover quickly after CPZ is removed. In contrast, neuroinflammation persists for at least two months following exposure and is mainly driven by astrocyte activation. The study warrants deeper analysis of the sustained neuroinflammatory response in the context of demyelinating diseases.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":"457-469"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13337915/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147513493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the Effect of Sorafenib on Gd-EOB-DTPA-mediated Contrast Enhancement: An Experimental Study using DCE-MRI.","authors":"Yeon Ji Chae, Do-Wan Lee, Chul-Woong Woo, Yu Sub Sung, Jung-Hyun Choi, Eunyoung Tak, Chang Hoon Ha, Jin Kyung Roh, In-Jeoung Baek, Chan-Gi Pack, Hwon Heo, Kyung Won Kim, Jeong Kon Kim, Yoonseok Choi, Dong-Cheol Woo","doi":"10.1007/s11307-026-02109-5","DOIUrl":"10.1007/s11307-026-02109-5","url":null,"abstract":"<p><strong>Purpose: </strong>Despite the potential impact of sorafenib on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-mediated contrast enhancements, attempts to assess these effects are rare. This study aimed to investigate the interaction between Sorafenib and Gd-EOB-DTPA by quantifying the T1 and T2 relaxation times and the relative enhancement rates (RERs) of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in the liver.</p><p><strong>Procedures: </strong>The effects on contrast enhancement were assessed using MRI with Chang liver cells and SD rats. MR phantom images were obtained after treating cells with varying dosages of Gd-EOB-DTPA (5, 10 mM) and sorafenib (10, 30 μM) to evaluate MR relaxivities. For the animal study, DCE-MRI was performed following intravenous administration of 25 µmol/kg Gd-EOB-DTPA and two different doses of sorafenib (10, 30 mg/kg). RER was analyzed to evaluate sorafenib's effects on Gd-EOB-DTPA uptake in the liver.</p><p><strong>Results: </strong>Phantom experiments demonstrated alterations in T1 and T2 values, with a tendency towards shortening disrupted by the addition of sorafenib to Gd-EOB-DTPA-treated Chang liver cells. The RERs of DCE-MRI in the liver exhibited a dose-dependent decrease following sorafenib administration, with recovery observed after 4 h.</p><p><strong>Conclusions: </strong>Our results provide quantitative information on sorafenib-mediated interference with Gd-EOB-DTPA-induced contrast enhancement and offer experimental evidence suggesting the possibility of drug-drug interactions between sorafenib and Gd-EOB-DTPA. Although further research is needed to fully elucidate the impact of these interactions, caution is warranted when using these two agents concurrently for liver MRI.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":"531-538"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147931380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diagnostic Performance of Somatostatin Receptor-directed PET/CT for Tumor-induced Osteomalacia.","authors":"Marieke Heinrich, Aleksander Kosmala, Alexander Dierks, Franca Genest, Elena Gerhard-Hartmann, Lukas Haug, Silke Achtziger, Peter Raab, Andreas K Buck, Constantin Lapa, Kerstin Michalski, Lothar Seefried","doi":"10.1007/s11307-026-02101-z","DOIUrl":"10.1007/s11307-026-02101-z","url":null,"abstract":"<p><strong>Aim: </strong>To evaluate the efficacy of somatostatin receptor (SSTR)-directed PET/CT in localizing phosphaturic mesenchymal tumors (PMT) in patients with suspected tumor-induced osteomalacia (TIO) and to explore relationships between imaging parameters and biochemical markers.</p><p><strong>Methods: </strong>This retrospective analysis included 20 patients with suspected TIO, undergoing SSTR-directed PET/CT. Imaging findings and laboratory markers were assessed. SSTR-positive tumors were resected, while patients without detectable tumor, but persistent renal phosphate wasting, continued on medical treatment. Follow-up assessments included laboratory values and clinical examinations.</p><p><strong>Results: </strong>PMT were detected on PET in 12 patients (60%), were resected, and confirmed immunohistochemically. Phosphorus levels (r = 0.26; p = 0.03), tubular reabsorption of phosphate (TRP; r = 0.77; p < 0.01) and tubular maximum of phosphate reabsorption over GFR (TmP/GFR; r = 0.44; p = 0.07) were lower in patients with detected PMT compared to those without. Elevation of fibroblast growth factor 23 (FGF23) was not significantly higher in PMT positive vs negative patients (253% vs 134% above the upper limit of normal; p = 0.97). Total lesion uptake (TLU) negatively correlated with TmP/GFR (r = -0.71; p = 0.03). A maximum standardized uptake value (SUVmax) threshold of 7.6 differentiated PMT from bone fractures (83% sensitivity; 100% specificity). Post-resection follow-up confirmed clinical cure in all cases.</p><p><strong>Conclusion: </strong>In SSTR-directed PET/CT, a distinction between PMT and bone fracture may be possible with a SUVmax threshold of 7.6. The integration of PET derived TLU, along with TmP/GFR may improve diagnosis and treatment planning for TIO.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":"513-522"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13337602/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147839980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}