The Development and Applications of a Dual Optical Imaging System for Studying Glioma Stem Cells.
In conclusion, we established a dual optical imaging system which enables the identification of CD133+ GSCs and screening for anti-GSC drugs. PMID: 31478435 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - September 4, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

PET/SPECT Molecular Probes for the Diagnosis and Staging of Nonalcoholic Fatty Liver Disease.
Authors: Shao T, Josephson L, Liang SH Abstract Nonalcoholic fatty liver disease (NAFLD) is a significant public health challenge afflicting approximately 1 billion individuals both in the Western world and in the East world. While liver biopsy is considered as gold standard in the diagnosis and staging of liver fibrosis, noninvasive imaging technologies, including ultrasonography, computed tomography, single-photon emission computed tomography (SPECT), magnetic resonance imaging, and positron emission tomography (PET) could offer more sensitive, comprehensive, and quantitative measurement for NAFLD. In this review...
Source: Molecular Imaging - September 4, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Improving PET Imaging Acquisition and Analysis With Machine Learning: A Narrative Review With Focus on Alzheimer's Disease and Oncology.
Authors: Duffy IR, Boyle AJ, Vasdev N Abstract Machine learning (ML) algorithms have found increasing utility in the medical imaging field and numerous applications in the analysis of digital biomarkers within positron emission tomography (PET) imaging have emerged. Interest in the use of artificial intelligence in PET imaging for the study of neurodegenerative diseases and oncology stems from the potential for such techniques to streamline decision support for physicians providing early and accurate diagnosis and allowing personalized treatment regimens. In this review, the use of ML to improve PET image acquisiti...
Source: Molecular Imaging - August 22, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Multiscale Mask R-CNN-Based Lung Tumor Detection Using PET Imaging.
Authors: Zhang R, Cheng C, Zhao X, Li X Abstract Positron emission tomography (PET) imaging serves as one of the most competent methods for the diagnosis of various malignancies, such as lung tumor. However, with an elevation in the utilization of PET scan, radiologists are overburdened considerably. Consequently, a new approach of "computer-aided diagnosis" is being contemplated to curtail the heavy workloads. In this article, we propose a multiscale Mask Region-Based Convolutional Neural Network (Mask R-CNN)-based method that uses PET imaging for the detection of lung tumor. First, we produced 3 models ...
Source: Molecular Imaging - August 2, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

18F-FDG PET/CT Quantitative Parameters and Texture Analysis Effectively Differentiate Endometrial Precancerous Lesion and Early-Stage Carcinoma.
This study evaluated the metabolic parameters and texture features of fluorodeoxyglucose positron emission tomography-computed tomography (PET/CT) for the diagnosis and differentiation of endometrial atypical hyperplasia (EAH), EAH with field cancerization (FC), and stage 1A endometrial carcinoma (EC 1a). MATERIALS AND METHODS: We retrospectively analyzed the metabolic parameters of PET/CT in 170 patients with diagnoses confirmed by pathology, including 57 cases of EAH (57/170, 33.53%), 45 cases of FC (45/170, 26.47%), and 68 cases of EC 1a (68/170, 40.0%). Then, the texture features of each tumor were extracted and co...
Source: Molecular Imaging - June 16, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Development of [18F]FPy-WL12 as a PD-L1 Specific PET Imaging Peptide.
Authors: Lesniak WG, Mease RC, Chatterjee S, Kumar D, Lisok A, Wharram B, Kalagadda VR, Emens LA, Pomper MG, Nimmagadda S Abstract Expression of programmed cell death ligand 1 (PD-L1) within tumors is an important biomarker for guiding immune checkpoint therapies; however, immunohistochemistry-based methods of detection fail to provide a comprehensive picture of PD-L1 levels in an entire patient. To facilitate quantification of PD-L1 in the whole body, we developed a peptide-based, high-affinity PD-L1 imaging agent labeled with [18F]fluoride for positron emission tomography (PET) imaging. The parent peptide, WL12, ...
Source: Molecular Imaging - June 13, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Prognostic and Predictive Values of Metabolic Parameters of 18F-FDG PET/CT in Patients With Non-Small Cell Lung Cancer Treated With Chemotherapy.
CONCLUSIONS: Several potential prognostic biomarkers of PET/CT imaging have been extracted for predicting survival and selecting patients with NSCLC who are more likely to benefit from chemotherapy. The identification may accelerate the development of AI methods to improve treatment outcome for NSCLC. PMID: 31144578 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - June 1, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Evaluating Cholinergic Receptor Expression in Guinea Pig Primary Auditory and Rostral Belt Cortices After Noise Damage Using [3H]Scopolamine and [18F]Flubatine Autoradiography.
Authors: Forrest TJ, Desmond TJ, Issa M, Scott PJH, Basura GJ Abstract Noise-induced hearing loss leads to anatomic and physiologic changes in primary auditory cortex (A1) and the adjacent dorsal rostral belt (RB). Since acetylcholine is known to modulate plasticity in other cortical areas, changes in A1 and RB following noise damage may be due to changes in cholinergic receptor expression. We used [3H]scopolamine and [18F]flubatine binding to measure muscarinic acetylcholine receptor (mAChR) and nicotinic acetylcholine receptor (nAChR) expression, respectively, in guinea pig A1 and RB 3 weeks following unilateral,...
Source: Molecular Imaging - May 19, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Immuno-PET Imaging of the Programmed Cell Death-1 Ligand (PD-L1) Using a Zirconium-89 Labeled Therapeutic Antibody, Avelumab.
CONCLUSIONS: [89Zr]Zr-DFO-PD-L1 mAb exhibited specific and high affinity for PD-L1 in vitro and had target tissue uptakes correlating with PD-L1 expression levels in vivo. [89Zr]Zr-DFO-PD-L1 mAb uptake in PD-L1+tumors increased with escalating doses of avelumab. PMID: 31044647 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - May 5, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

A Simple Ex Vivo Semiquantitative Fluorescent Imaging Utilizing Planar Laser Scanner: Detection of Reactive Oxygen Species Generation in Mouse Brain and Kidney.
CONCLUSIONS:: We successfully obtained ex vivo semiquantitative fluorescent images of ROS generation utilizing a planar laser scanner and DHE. This simple method is useful for ROS detection in several ROS-related animal models and would be applicable to a variety of biochemical processes. PMID: 30799681 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - February 27, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

PET Imaging of Hepatocellular Carcinomas: 18F-Fluoropropionic Acid as a Complementary Radiotracer for 18F-Fluorodeoxyglucose.
Authors: Zhao J, Zhang Z, Nie D, Ma H, Yuan G, Su S, Liu S, Liu S, Tang G Abstract OBJECTIVE:: To evaluate the preclinical value of 18F-fluoropropionic acid (18F-FPA) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) for imaging HCCs. METHODS:: The 18F-FPA and 18F-FDG uptake patterns in 3 HCC cell lines (Hep3B, HepG2, and SK-Hep1) were assessed in vitro and in vivo. The 18F-FPA uptake mechanism was investigated using inhibition experiments with orlistat and 5-tetradecyloxy-2-furoic acid. The 18F-FPA PET imaging was performed in different tumor animal models and compared with 18F-FDG. We al...
Source: Molecular Imaging - February 27, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Altered Forebrain Functional Connectivity and Neurotransmission in a Kinase-Inactive Met Mouse Model of Autism.
Authors: Tang S, Powell EM, Zhu W, Lo FS, Erzurumlu RS, Xu S Abstract MET, the gene encoding the tyrosine kinase receptor for hepatocyte growth factor, is a susceptibility gene for autism spectrum disorder (ASD). Genetically altered mice with a kinase-inactive Met offer a potential model for understanding neural circuit organization changes in autism. Here, we focus on the somatosensory thalamocortical circuitry because distinct somatosensory sensitivity phenotypes accompany ASD, and this system plays a major role in sensorimotor and social behaviors in mice. We employed resting-state functional magnetic resonance ...
Source: Molecular Imaging - February 27, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Analysis of Progress and Challenges of EGFR-Targeted Molecular Imaging in Cancer With a Focus on Affibody Molecules.
Authors: Chen W, Shen B, Sun X Abstract Epidermal growth factor receptor (EGFR)-targeted cancer therapy requires an accurate estimation of EGFR expression in tumors to identify responsive patients, monitor therapeutic effect, and estimate prognosis. The EGFR molecular imaging is an optimal method for evaluating EGFR expression in vivo accurately and noninvasively. In this review, we discuss the recent advances in EGFR-targeted molecular imaging in cancer, with a special focus on the development of imaging agents, including epidermal growth factor (EGF) ligand, monoclonal antibodies, antibody fragments, Affibody, an...
Source: Molecular Imaging - February 27, 2019 Category: Radiology Tags: Mol Imaging Source Type: research

Magnetic Resonance Imaging for Characterization of a Chick Embryo Model of Cancer Cell Metastases.
Authors: Herrmann A, Taylor A, Murray P, Poptani H, Sée V Abstract Metastasis is the most common cause of death for patients with cancer. To fully understand the steps involved in metastatic dissemination, in vivo models are required, of which murine ones are the most common. Therefore, preclinical imaging methods such as magnetic resonance imaging (MRI) have mainly been developed for small mammals and their potential to monitor cancer growth and metastasis in nonmammalian models is not fully harnessed. We have here used MRI to measure primary neuroblastoma tumor size and metastasis in a chick embryo model. ...
Source: Molecular Imaging - November 6, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Development and Characterization of an 18F-labeled Ghrelin Peptidomimetic for Imaging the Cardiac Growth Hormone Secretagogue Receptor.
Authors: Abbas A, Yu L, Lalonde T, Wu D, Thiessen JD, Luyt LG, Dhanvantari S Abstract One-third of patients with heart disease develop heart failure, which is diagnosed through imaging and detection of circulating biomarkers. Imaging strategies reveal morphologic and functional changes but fall short of detecting molecular abnormalities that can lead to heart failure, and circulating biomarkers are not cardiac specific. Thus, there is critical need for biomarkers that are endogenous to myocardial tissues. The cardiac growth hormone secretagogue receptor 1a (GHSR1a), which binds the hormone ghrelin, is a potential b...
Source: Molecular Imaging - November 6, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Application of Immuno-PET in Antibody-Drug Conjugate Development.
Authors: Carmon KS, Azhdarinia A Abstract Targeted therapies hold great promise for cancer treatment and may exhibit even greater efficacy when combined with patient selection tools. The clinical impact of identifying likely responders includes reducing the number of unnecessary and ineffective therapies as well as more accurately determining drug effects. Positron emission tomography (PET) imaging using zirconium-89 radiolabeled monoclonal antibodies (mAbs), also referred to as zirconium-89 (89Zr)-immuno-PET, provides a potential biomarker to measure target expression and verify optimal delivery of targeted agents...
Source: Molecular Imaging - October 30, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Adamantane/Cucurbituril: A Potential Pretargeted Imaging Strategy in Immuno-PET.
We report our initial findings concerning the suitability of the adamantane/cucurbit[7]uril system for pretargeted immuno-PET imaging and provide proof-of-concept PET/computed tomography imaging experiments to establish the stability and rapid formation of host-guest complexes in vivo. The adamantane/cucurbit[7]uril system itself without antibody conjugation has shown remarkably fast association kinetics and clearance in vivo. We further demonstrate the modulation of biodistribution achievable by cucurbituril complexation with relevance for pharmaceutical formulation as well as the radiosynthetic access to relevant reporte...
Source: Molecular Imaging - October 27, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Apoptotic PET Imaging of Rat Pulmonary Fibrosis With [18F]ML-8.
Authors: Xiong Y, Nie D, Liu S, Ma H, Su S, Sun A, Zhao J, Zhang Z, Xiang X, Tang G Abstract OBJECTIVE:: To investigate the value of 2-(3-[18F]fluoropropyl)-2-methyl-malonic acid ([18F]ML-8) positron emission tomography (PET) imaging of rat pulmonary fibrosis. METHODS:: Male Sprague-Dawley rats were divided into 2 groups, including pulmonary fibrosis model group and control group. The rat model was established by an intratracheal instillation of bleomycin (BLM). Control rats were treated with saline. Positron emission tomography/computed tomography (CT) with [18F]ML-8 or 18F-fluorodeoxyglucose ([18F]FDG) was pe...
Source: Molecular Imaging - October 24, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Preclinical Ultrasound-Guided Photoacoustic Imaging of the Placenta in Normal and Pathologic Pregnancy.
Authors: Yamaleyeva LM, Brosnihan KB, Smith LM, Sun Y Abstract Placental oxygenation varies throughout pregnancy. The detection of early changes in placental oxygenation as pregnancy progresses is important for early identification of preeclampsia or other complications. This invited commentary discusses a recent preclinical study on the application of 3-dimensional photoacoustic imaging (PAI) for assessment of regional variations in placental oxygenation and longitudinal analysis of differences in placental oxygenation throughout normal pregnancy and pregnancy associated with hypertension or placental insufficienc...
Source: Molecular Imaging - October 24, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Pharmacokinetic Evaluation of [11C]CEP-32496 in Nude Mice Bearing BRAFV600E Mutation-Induced Melanomas.
Authors: Jiang C, Xie L, Zhang Y, Fujinaga M, Mori W, Kurihara Y, Yamasaki T, Wang F, Zhang MR Abstract CEP-32496, also known as RXDX-105 or Agerafenib, is a new orally active inhibitor for the mutated v-raf murine sarcoma viral oncogene homolog B1 (BRAFV600E), which has attracted considerable attention in clinical trials for the treatment of human cancers. Here, we used carbon-11-labeled CEP-32496 ([11C]CEP-32496) as a positron emission tomography (PET) radiotracer to evaluate its pharmacokinetic properties and explore its potential for in vivo imaging. Following radiotracer synthesis, we performed in vitro bindin...
Source: Molecular Imaging - September 27, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Rare-Earth-Doped Nanoparticles for Short-Wave Infrared Fluorescence Bioimaging and Molecular Targeting of αVβ3-Expressing Tumors.
Rare-Earth-Doped Nanoparticles for Short-Wave Infrared Fluorescence Bioimaging and Molecular Targeting of αVβ3-Expressing Tumors. Mol Imaging. 2018 Jan-Dec;17:1536012118799131 Authors: Naczynski DJ, Stafford JH, Türkcan S, Jenkins C, Koh AL, Sun C, Xing L Abstract The use of short-wave infrared (SWIR) light for fluorescence bioimaging offers the advantage of reduced photon scattering and improved tissue penetration compared to traditional shorter wavelength imaging approaches. While several nanomaterials have been shown capable of generating SWIR emissions, rare-earth-doped nanoparticle...
Source: Molecular Imaging - September 26, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Acute Ketamine Infusion in Rat Does Not Affect In Vivo [11C]ABP688 Binding to Metabotropic Glutamate Receptor Subtype 5.
In conclusion, we could not confirm in rats that endogenous glutamate increases by ketamine infusion are reflected in [11C]ABP688 binding decreases as was previously shown for humans. PMID: 30213221 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - September 16, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

From Micro- to Nano-Multifunctional Theranostic Platform: Effective Ultrasound Imaging Is Not Just a Matter of Scale.
Authors: Zullino S, Argenziano M, Stura I, Guiot C, Cavalli R Abstract Ultrasound Contrast Agents (UCAs) consisting of gas-filled-coated Microbubbles (MBs) with diameters between 1 and 10 µm have been used for a number of decades in diagnostic imaging. In recent years, submicron contrast agents have proven to be a viable alternative to MBs for ultrasound (US)-based applications for their capability to extravasate and accumulate in the tumor tissue via the enhanced permeability and retention effect. After a short overview of the more recent approaches to ultrasound-mediated imaging and therapeutics at the nano...
Source: Molecular Imaging - September 16, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

The Binding of BF-227-Like Benzoxazoles to Human α-Synuclein and Amyloid β Peptide Fibrils.
The Binding of BF-227-Like Benzoxazoles to Human α-Synuclein and Amyloid β Peptide Fibrils. Mol Imaging. 2018 Jan-Dec;17:1536012118796297 Authors: Josephson L, Stratman N, Liu Y, Qian F, Liang SH, Vasdev N, Patel S Abstract Development of an α-synuclein (α-Syn) positron emission tomography agent for the diagnosis and evaluation of Parkinson disease therapy is a key goal of neurodegenerative disease research. BF-227 has been described as an α-Syn binder and hence was employed as a lead to generate a library of α-Syn-binding compounds. [3H]BF-227 bound to α-Syn an...
Source: Molecular Imaging - September 16, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

The Molecular Imaging of Natural Killer Cells.
Authors: Shapovalova M, Pyper SR, Moriarity BS, LeBeau AM Abstract The recent success of autologous T cell-based therapies in hematological malignancies has spurred interest in applying similar immunotherapy strategies to the treatment of solid tumors. Identified nearly 4 decades ago, natural killer (NK) cells represent an arguably better cell type for immunotherapy development. Natural killer cells are cytotoxic lymphocytes that mediate the direct killing of transformed cells with reduced or absent major histocompatibility complex (MHC) and are the effector cells in antibody-dependent cell-mediated cytotoxicity. U...
Source: Molecular Imaging - September 13, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Emerging PET Radiotracers and Targets for Imaging of Neuroinflammation in Neurodegenerative Diseases: Outlook Beyond TSPO.
Authors: Narayanaswami V, Dahl K, Bernard-Gauthier V, Josephson L, Cumming P, Vasdev N Abstract The dynamic and multicellular processes of neuroinflammation are mediated by the nonneuronal cells of the central nervous system, which include astrocytes and the brain's resident macrophages, microglia. Although initiation of an inflammatory response may be beneficial in response to injury of the nervous system, chronic or maladaptive neuroinflammation can have harmful outcomes in many neurological diseases. An acute neuroinflammatory response is protective when activated neuroglia facilitate tissue repair by releasing ...
Source: Molecular Imaging - September 13, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Capturing Bone Signal in MRI of Pelvis, as a Large FOV Region, Using TWIST Sequence and Generating a 5-Class Attenuation Map for Prostate PET/MRI Imaging.
CONCLUSIONS: According to the SNRSTE, pelvic bone, the cortical bone can be separate from air cavity in STE imaging based on TWIST sequence. The proposed method generated an MRI-based µ-map containing bone and air cavity that led to more accurate tracer uptake estimation than MRAC4c. Uptake estimation in hybrid PET/MRI can be improved by employing the proposed method. PMID: 30064303 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - August 5, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Evaluation of a Tumor-Targeting, Near-Infrared Fluorescent Peptide for Early Detection and Endoscopic Resection of Polyps in a Rat Model of Colorectal Cancer.
Authors: Jones JE, Busi SB, Mitchem JB, Amos-Landgraf JM, Lewis MR Abstract The goal of these studies was to use a tumor-targeting, near-infrared (NIR) fluorescent peptide to evaluate early detection and to guide surgical removal of polyps in a genetically engineered rat model of spontaneous colorectal cancer. This peptide, LS301, was conjugated to Cy7.5 and applied topically to the colon of adenoma-bearing Pirc rats. Ten minutes after administration, rats underwent targeted NIR laser colonoscopy. Rats were also evaluated by white light colonoscopy and narrow-band imaging, for comparison to the NIR technique. Unlik...
Source: Molecular Imaging - August 5, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Quantification of Cerenkov Luminescence Imaging (CLI) Comparable With 3-D PET Standard Measurements.
In this study, we developed a model that estimates effective tissue attenuation coefficient and corrects the tissue attenuation of CLI signal intensity independent of tissue depth and size. To evaluate this model, we used several thin slices of ham as a phantom and placed a radionuclide (89Zr and 64Cu) inside the phantom at different tissue depths and sizes (2, 7, and 12 mm). We performed 2-D CLI and MicroPET/CT (Combined small animal PET and Computed Tomography (CT)) imaging of the phantom and in vivo mouse model after administration of 89Zr tracer. Estimates of the effective tissue attenuation coefficient (μeff) for 8...
Source: Molecular Imaging - July 27, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Detecting Demyelination by PET: The Lesion as Imaging Target.
Authors: Brugarolas P, Reich DS, Popko B Abstract Noninvasive imaging of demyelination and remyelination is critical for diagnosis and clinical management of demyelinating diseases. Positron emission tomography (PET) has the potential to complement magnetic resonance imaging (MRI) by providing a quantitative measure specific to demyelination. In Brugarolas et al's study 1 , we describe the development of the first PET tracer for voltage-gated K+ channels based on a clinically approved drug for multiple sclerosis that can be used for imaging demyelination in animal models. PMID: 30039728 [PubMed - in process] (S...
Source: Molecular Imaging - July 25, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

A Comparison of Iron Oxide Particles and Silica Particles for Tracking Organ Recellularization.
This study investigated whether ultrasound imaging or magnetic resonance imaging (MRI) can track the reseeding of murine liver scaffolds with silica-labeled or iron-labeled liver hepatocytes. Mesoporous silica particles were created using the Stöber method, loaded with Alexa Flour 647 fluorophore, and conjugated with protamine sulfate, glutamine, and glycine. Fluorescent iron oxide particles were obtained from a commercial source. Liver cells from donor mice were loaded with the silica particles or iron oxide particles. Donor livers were decellularized and reperfused with silica-labeled or iron-labeled cells. The rese...
Source: Molecular Imaging - July 25, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

An Exploratory Study of Washout Rate Analysis for Thallium-201 Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging Using Cadmium Zinc Telluride Detectors.
Authors: Ishihara M, Onoguchi M, Shibutani T Abstract The aim of this study was to assess the washout rate (WOR) for thallium-201-chloride single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) using cadmium zinc telluride detectors for SPECT (CZT SPECT) versus conventional Anger-type SPECT (conventional SPECT). A total of 52 Japanese patients were examined using CZT SPECT and conventional SPECT, and the global WORs were compared. Additionally, the MPI WORs were compared for patients with a normal MPI versus those in whom MPI reflected the patients' multivessel disease (MVD) MPI. Wash...
Source: Molecular Imaging - June 29, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Melanocortin 1 Receptor Targeted Imaging of Melanoma With Gold Nanocages and Positron Emission Tomography.
CONCLUSION: The controlled synthesis, sensitive PET imaging, and optimal tumor targeting suggested the potential of targeted AuNCs for melanoma theranostics. PMID: 29873290 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - June 8, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

PSMA Theranostics: Current Status and Future Directions.
Authors: Rahbar K, Afshar-Oromieh A, Jadvar H, Ahmadzadehfar H Abstract Prostate-specific membrane antigen (PSMA) is a promising target for imaging diagnostics and targeted radionuclide therapy (theranostics) of prostate cancer and its metastases. There is increasing evidence of encouraging response rates and a low toxicity profile of radioligand therapy (RLT) of metastatic castration-resistant prostate cancer using 177Lu-labeled PSMA ligands. In this article, we review the current status of diagnostics and therapy using radiolabeled PSMA ligands. We also suggest protocols for patient selection criteria and conduct...
Source: Molecular Imaging - June 8, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Reversible Electroporation-Mediated Liposomal Doxorubicin Delivery to Tumors Can Be Monitored With 89Zr-Labeled Reporter Nanoparticles.
Authors: Srimathveeravalli G, Abdel-Atti D, Pérez-Medina C, Takaki H, Solomon SB, Mulder WJM, Reiner T Abstract Reversible electroporation (RE) can facilitate nanoparticle delivery to tumors through direct transfection and from changes in vascular permeability. We investigated a radiolabeled liposomal nanoparticle (89Zr-NRep) for monitoring RE-mediated liposomal doxorubicin (DOX) delivery in mouse tumors. Intravenously delivered 89Zr-NRep allowed positron emission tomography imaging of electroporation-mediated nanoparticle uptake. The relative order of 89Zr-NRep injection and electroporation did not result i...
Source: Molecular Imaging - February 28, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Targeting HER2 in Nuclear Medicine for Imaging and Therapy.
Authors: Massicano AVF, Marquez-Nostra BV, Lapi SE Abstract Since its discovery, the human epidermal growth factor 2 (HER2) has been extensively studied. Presently, there are 2 standard diagnostic techniques to assess HER2 status in biopsies: immunohistochemistry and fluorescence in situ hybridization. While these techniques have played an important role in the treatment of patients with HER2-positive cancer, they both require invasive biopsies for analysis. Moreover, the expression of HER2 is heterogeneous in breast cancer and can change over the course of the disease. Thus, the degree of HER2 expression in the sm...
Source: Molecular Imaging - January 25, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Commentary to 18F-GP1, a Novel PET Tracer Designed for High-Sensitivity, Low-Background Detection of Thrombi: Imaging Activated Platelets in Clots-Are We Getting There?
Authors: Stephens AW, Koglin N, Dinkelborg LM Abstract Thrombus formation can lead to heart attacks, stroke and pulmonary embolism, which are major causes of mortality. Current standard diagnostic imaging methods detect anatomic abnormalities such as vascular flow impairment but have limitations. By using a targeted molecular imaging approach critical components of a pathology can be selectively visualized and exploited for an improved diagnosis and patient management. The GPIIb/IIIa receptor is abundantly and specifically exposed on activated platelets and is the key receptor in thrombus formation. This commentary...
Source: Molecular Imaging - January 21, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Decreased Taurine and Creatine in the Thalamus May Relate to Behavioral Impairments in Ethanol-Fed Mice: A Pilot Study of Proton Magnetic Resonance Spectroscopy.
Authors: Xu S, Zhu W, Wan Y, Wang J, Chen X, Pi L, Lobo MK, Ren B, Ying Z, Morris M, Cao Q Abstract Minimal hepatic encephalopathy (MHE) is highly prevalent, observed in up to 80% of patients with liver dysfunction. Minimal hepatic encephalopathy is defined as hepatic encephalopathy with cognitive deficits and no grossly evident neurologic abnormalities. Clinical management may be delayed due to the lack of in vivo quantitative methods needed to reveal changes in brain neurobiochemical biomarkers. To gain insight into the development of alcoholic liver disease-induced neurological dysfunction (NDF), a mouse model o...
Source: Molecular Imaging - January 12, 2018 Category: Radiology Tags: Mol Imaging Source Type: research

Contrast-Enhanced Near-Infrared Optical Imaging Detects Exacerbation and Amelioration of Murine Muscular Dystrophy.
Authors: Chrzanowski SM, Vohra RS, Lee-McMullen BA, Batra A, Spradlin RA, Morales J, Forbes S, Vandenborne K, Barton ER, Walter GA Abstract Assessment of muscle pathology is a key outcome measure to measure the success of clinical trials studying muscular dystrophies; however, few robust minimally invasive measures exist. Indocyanine green (ICG)-enhanced near-infrared (NIR) optical imaging offers an objective, minimally invasive, and longitudinal modality that can quantify pathology within muscle by imaging uptake of ICG into the damaged muscles. Dystrophic mice lacking dystrophin (mdx) or gamma-sarcoglycan (Sgcg-/...
Source: Molecular Imaging - December 23, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Radiolabeled Anti-Adenosine Triphosphate Synthase Monoclonal Antibody as a Theragnostic Agent Targeting Angiogenesis.
CONCLUSION: The specific binding and antitumor effects of radioiodinated ATPS mAb were confirmed in in vitro and in vivo models of stomach cancer. PMID: 29239276 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - December 16, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Molecular Imaging and Radionuclide Therapy of Melanoma Targeting the Melanocortin 1 Receptor.
In this study, we summarized the development and the in vitro and in vivo characteristics of the radiolabeled αMSH analogues, including 99mTc-, 111In-, 67 Ga-, or 125I-labeled αMSH analogues for imaging with single-photon emission computed tomography; 68Ga-, 64Cu-, or 18F-labeled αMSH analogues for imaging with positron emission tomography; and 188Re-, 177Lu-, 90Y-, or 212Pb-labeled αMSH analogues for radionuclide therapy. These radiolabeled αMSH analogues showed promising results with high tumor uptake and rapid normal tissue activity clearance in the preclinical model of B16F1 and B16F10 mou...
Source: Molecular Imaging - November 30, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Molecular Imaging of IGF-1R in Cancer.
Authors: Sun Y, Sun X, Shen B Abstract The important role of insulin-like growth factor 1 receptor (IGF-1R) in malignant tumors has been well established. Increased IGF-1R activity promotes cancer cell proliferation, migration, and invasion and is associated with tumor metastasis, treatment resistance, poor prognosis, and shortened survival in patients with cancer. However, while IGF-1R has become a promising target for cancer therapy, IGF-1R-targeted therapy is ineffective in unselected patients. It is therefore essential to evaluate IGF-1R expression before treatment in order to identify responsive patients, moni...
Source: Molecular Imaging - November 26, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Effect of Time-of-Flight and Regularized Reconstructions on Quantitative Measurements and Qualitative Assessments in Newly Diagnosed Prostate Cancer With (18)F-Fluorocholine Dual Time Point PET/MRI.
Authors: Behr SC, Mollard BJ, Yang J, Flavell RR, Hawkins RA, Seo Y Abstract Recent technical advances in positron emission tomography/magnetic resonance imaging (PET/MRI) technology allow much improved time-of-flight (TOF) and regularized iterative PET reconstruction regularized iterative reconstruction (RIR) algorithms. We evaluated the effect of TOF and RIR on standardized uptake values (maximum and peak SUV [SUVmax and SUVpeak]) and their metabolic tumor volume dependencies and visual image quality for (18)F-fluorocholine PET/MRI in patients with newly diagnosed prostate cancer. Fourteen patients were administe...
Source: Molecular Imaging - November 26, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Radiochemistry and Preclinical PET Imaging of (68)Ga-Desferrioxamine Radiotracers Targeting Prostate-Specific Membrane Antigen.
Authors: Gourni E, Del Pozzo L, Bartholomä M, Kiefer Y, T Meyer P, Maecke HR, Holland JP Abstract Radiotracers incorporating the urea-based Glu-NH-C(O)-NH-Lys group have gained prominence due to their role in targeting prostate-specific membrane antigen (PSMA)-a clinical biomarker of prostate cancer. Here, the synthesis, radiolabeling, and in vitro and in vivo characterization of two (68)Ga-radiolabeled Glu-NH-C(O)-NH-Lys radiotracers conjugated to the desferrioxamine B (DFO) chelate were evaluated. Two linker groups based on amide bond and thiourea coupling chemistries were employed to develop (68)Ga-DFO-Nsuc...
Source: Molecular Imaging - November 5, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Brain Penetration of the ROS1/ALK Inhibitor Lorlatinib Confirmed by PET.
Authors: Collier TL, Maresca KP, Normandin MD, Richardson P, McCarthy TJ, Liang SH, Waterhouse RN, Vasdev N Abstract The Massachusetts General Hospital Radiochemistry Program, in collaboration with Pfizer, has developed unique (11)C and (18)F-labeling strategies to synthesize isotopologs of lorlatinib (PF-06463922) which is undergoing phase III clinical trial investigations for treatment of non-small-cell lung cancers with specific molecular alterations. A major goal in cancer therapeutics is to measure the concentrations of this drug in the brain metastases of patients with lung cancer, and penetration of the bloo...
Source: Molecular Imaging - October 28, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [(11)C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism.
CONCLUSION: First, mean effective dose of [(11)C]palmitate is 3.23 (0.02) µSv/MBq in humans allowing multiple scans using ∼300 MBq [(11)C]palmitate, and secondly, population-based metabolite correction compares well with individual correction. PMID: 29073808 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - October 28, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

First-in-Man Evaluation of (124)I-PGN650: A PET Tracer for Detecting Phosphatidylserine as a Biomarker of the Solid Tumor Microenvironment.
CONCLUSION: Although (124)I-PGN650 is safe for human PET imaging, the tumor targeting with this agent in patients was less than previously observed in animal studies. PMID: 29037107 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - October 20, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Whole-Body Distribution of Leukemia and Functional Total Marrow Irradiation Based on FLT-PET and Dual-Energy CT.
In conclusion, a hybrid system of functional-anatomical-physiological imaging can identify the spatial distribution of leukemia and will be useful to both help understand the leukemia niche and develop targeted radiation strategies. PMID: 28948859 [PubMed - in process] (Source: Molecular Imaging)
Source: Molecular Imaging - September 29, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Molecular Imaging of Hydrolytic Enzymes Using PET and SPECT.
Authors: Rempel BP, Price EW, Phenix CP Abstract Hydrolytic enzymes are a large class of biological catalysts that play a vital role in a plethora of critical biochemical processes required to maintain human health. However, the expression and/or activity of these important enzymes can change in many different diseases and therefore represent exciting targets for the development of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) radiotracers. This review focuses on recently reported radiolabeled substrates, reversible inhibitors, and irreversible inhibitors investigated as ...
Source: Molecular Imaging - September 21, 2017 Category: Radiology Tags: Mol Imaging Source Type: research

Rethinking Brain Cancer Therapy: Tumor Enzyme Activatable Theranostic Nanoparticles.
Authors: Daldrup-Link HE Abstract This invited commentary discusses a recent article by Mohanty et al in Molecular Cancer Therapeutics about significant therapeutic efficacies of novel theranostic nanoparticles (TNPs) for the treatment of human brain cancers in mouse models. The TNPs were cleaved by enzymes in the tumor tissue, matrix metalloproteinase (MMP-14), which lead to release of a highly potent therapeutic drug, azademethylcolchicine. Data showed that the TNPs caused selective toxic effects in MMP-14-expressing glioblastoma and not normal brain. In addition, the iron oxide nanoparticle backbone enabled in v...
Source: Molecular Imaging - September 21, 2017 Category: Radiology Tags: Mol Imaging Source Type: research