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PET Clinics Oct 2023
Topics: Humans; Female; Breast Neoplasms; Mammography; Molecular Imaging
PubMed: 37330407
DOI: 10.1016/j.cpet.2023.05.003 -
Chemical Science Dec 2023Molecular imaging, including quantification and molecular interaction studies, plays a crucial role in visualizing and analysing molecular events occurring within cells... (Review)
Review
Molecular imaging, including quantification and molecular interaction studies, plays a crucial role in visualizing and analysing molecular events occurring within cells or organisms, thus facilitating the understanding of biological processes. Moreover, molecular imaging offers promising applications for early disease diagnosis and therapeutic evaluation. Aptamers are oligonucleotides that can recognize targets with a high affinity and specificity by folding themselves into various three-dimensional structures, thus serving as ideal molecular recognition elements in molecular imaging. This review summarizes the commonly employed aptamers in molecular imaging and outlines the prevalent design approaches for their applications. Furthermore, it highlights the successful application of aptamers to a wide range of targets and imaging modalities. Finally, the review concludes with a forward-looking perspective on future advancements in aptamer-based molecular imaging.
PubMed: 38098720
DOI: 10.1039/d3sc03989g -
Radiology Nov 2023
Topics: Humans; Medical Oncology; Neoplasms; Molecular Imaging
PubMed: 37987660
DOI: 10.1148/radiol.231930 -
Science (New York, N.Y.) Jul 2023The historically important phage ΦX174 kills its host bacteria by encoding a 91-residue protein antibiotic called protein E. Using single-particle electron...
The historically important phage ΦX174 kills its host bacteria by encoding a 91-residue protein antibiotic called protein E. Using single-particle electron cryo-microscopy, we demonstrate that protein E bridges two bacterial proteins to form the transmembrane YES complex [MraY, protein E, sensitivity to lysis D (SlyD)]. Protein E inhibits peptidoglycan biosynthesis by obstructing the MraY active site leading to loss of lipid I production. We experimentally validate this result for two different viral species, providing a clear model for bacterial lysis and unifying previous experimental data. Additionally, we characterize the MraY structure-revealing features of this essential enzyme-and the structure of the chaperone SlyD bound to a protein. Our structures provide insights into the mechanism of phage-mediated lysis and for structure-based design of phage therapeutics.
Topics: Anti-Bacterial Agents; Bacteriolysis; Bacteriophage phi X 174; Escherichia coli; Escherichia coli Proteins; Peptidylprolyl Isomerase; Viral Proteins; Single Molecule Imaging; Cryoelectron Microscopy
PubMed: 37440661
DOI: 10.1126/science.adg9091 -
RMD Open Feb 2024It is known that metabolic shifts and tissue remodelling precede the development of visible inflammation and structural organ damage in inflammatory rheumatic diseases... (Review)
Review
It is known that metabolic shifts and tissue remodelling precede the development of visible inflammation and structural organ damage in inflammatory rheumatic diseases such as the inflammatory arthritides. As such, visualising and measuring metabolic tissue activity could be useful to identify biomarkers of disease activity already in a very early phase. Recent advances in imaging have led to the development of so-called 'metabolic imaging' tools that can detect these changes in metabolism in an increasingly accurate manner and non-invasively.Nuclear imaging techniques such as F-D-glucose and fibroblast activation protein inhibitor-labelled positron emission tomography are increasingly used and have yielded impressing results in the visualisation (including whole-body staging) of inflammatory changes in both early and established arthritis. Furthermore, optical imaging-based bedside techniques such as multispectral optoacoustic tomography and fluorescence optical imaging are advancing our understanding of arthritis by identifying intra-articular metabolic changes that correlate with the onset of inflammation with high precision and without the need of ionising radiation.Metabolic imaging holds great potential for improving the management of patients with inflammatory arthritis by contributing to early disease interception and improving diagnostic accuracy, thereby paving the way for a more personalised approach to therapy strategies including preventive strategies. In this narrative review, we discuss state-of-the-art metabolic imaging methods used in the assessment of arthritis and inflammation, and we advocate for more extensive research endeavours to elucidate their full field of application in rheumatology.
Topics: Humans; Arthritis; Inflammation; Tomography, X-Ray Computed; Positron-Emission Tomography; Molecular Imaging
PubMed: 38341194
DOI: 10.1136/rmdopen-2023-003880 -
Seminars in Nuclear Medicine Jul 2023Neuroblastoma is the most common extracranial solid tumor in children and arises from anywhere along the sympathetic nervous system. It is a highly heterogeneous disease... (Review)
Review
Neuroblastoma is the most common extracranial solid tumor in children and arises from anywhere along the sympathetic nervous system. It is a highly heterogeneous disease with a wide range of prognosis, from spontaneous regression or maturing to highly aggressive. About half of pediatric neuroblastoma patients develop the metastatic disease at diagnosis, which carries a poor prognosis. Nuclear medicine plays a pivotal role in the diagnosis, staging, response assessment, and long-term follow-up of neuroblastoma. And it has also played a prominent role in the treatment of neuroblastoma. Because the structure of metaiodobenzylguanidine (MIBG) is similar to that of norepinephrine, 90% of neuroblastomas are MIBG-avid. I-MIBG whole-body scintigraphy is the standard nuclear imaging technique for neuroblastoma, usually in combination with SPECT/CT. However, approximately 10% of neuroblastomas are MIBG nonavid. PET imaging has many technical advantages over SPECT imaging, such as higher spatial and temporal resolution, higher sensitivity, superior quantitative capability, and whole-body tomographic imaging. In recent years, various tracers have been used for imaging neuroblastoma with PET. The importance of patient-specific targeted radionuclide therapy for neuroblastoma therapy has also increased. I-MIBG therapy is part of the front-line treatment for children with high-risk neuroblastoma. And peptide receptor radionuclide therapy with radionuclide-labeled somatostatin analogues has been successfully used in the therapy of neuroblastoma. Moreover, radioimmunoimaging has important applications in the diagnosis of neuroblastoma, and radioimmunotherapy may provide a novel treatment modality against neuroblastoma. This review discusses the use of current and novel radiopharmaceuticals in nuclear medicine imaging and therapy of neuroblastoma.
Topics: Child; Humans; 3-Iodobenzylguanidine; Neuroblastoma; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Molecular Imaging
PubMed: 36682980
DOI: 10.1053/j.semnuclmed.2022.12.004 -
Clinical Neuropathology 2023Molecular characterization has become a key diagnostic tool for the classification and grading of primary brain tumors. Molecular markers, such as mutation status,...
Molecular characterization has become a key diagnostic tool for the classification and grading of primary brain tumors. Molecular markers, such as mutation status, codeletion, methylation of the promoter, or homozygous deletion discriminate different tumor entities and grades, and play a crucial role for treatment response and prognosis. In recent years, magnetic resonance imaging (MRI), whose main functions has been to detect a tumor, to provide spatial information for neurosurgical and radiotherapy planning, and to monitor treatment response, has shown potential in assessing molecular features of gliomas from image-based biomarkers. As an outstanding example, numerous studies have proven that the T2/FLAIR mismatch sign can identify -mutant, non-codeleted astrocytomas with a specificity of up to 100%. For other purposes, multiparametric MRI, often coupled with machine learning methods, seems to achieve the highest accuracy in predicting molecular markers. Relevant future applications might be anticipating changes in the molecular composition of gliomas and providing useful information about the cellular and genetic heterogeneity of gliomas, especially in the non-resected tumor parts.
Topics: Humans; Brain Neoplasms; Homozygote; Sequence Deletion; Glioma; Magnetic Resonance Imaging; Mutation; Biomarkers; Molecular Imaging; Isocitrate Dehydrogenase; Chromosomes, Human, Pair 1
PubMed: 36999510
DOI: 10.5414/NP301535 -
Nuklearmedizin. Nuclear Medicine Oct 2023Therapeutics that specifically address biological processes often require a much finer selection of patients and subclassification of diseases. Thus, diagnostic... (Review)
Review
BACKGROUND
Therapeutics that specifically address biological processes often require a much finer selection of patients and subclassification of diseases. Thus, diagnostic procedures must describe the diseases in sufficient detail to allow selection of appropriate therapy and to sensitively track therapy response. Anatomical features are often not sufficient for this purpose and there is a need to image molecular and pathophysiological processes.
METHOD
Two imaging strategies can be pursued: molecular imaging attempts to image a few biomarkers that play key roles in pathological processes. Alternatively, patterns describing a biological process can be identified from the synopsis of multiple (non-specific) imaging markers, possibly in combination with omics and other clinical findings. Here, AI-based methods are increasingly being used.
RESULTS
Both strategies of evidence-based therapy management are explained in this review article and examples and clinical successes are presented. In this context, reviews of clinically approved molecular diagnostics and decision support systems are listed. Furthermore, since reliable, representative, and sufficiently large datasets are further important prerequisites for AI-assisted multiparametric analyses, concepts are presented to make data available in a structured way, e. g., using Generative Adversarial Networks to complement databases with virtual cases and to build completely anonymous reference databases.
CONCLUSION
Molecular imaging and computer-assisted cluster analysis of diagnostic data are complementary methods to describe pathophysiological processes. Both methods have the potential to improve (evidence-based) the future management of therapies, partly on their own but also in combined approaches.
KEY POINTS
· Molecular imaging and radiomics provide valuable complementary disease biomarkers.. · Data-driven, model-based, and hybrid model-based integrated diagnostics advance precision medicine.. · Synthetic data generation may become essential in the development process of future AI methods..
Topics: Humans; Biomarkers; Precision Medicine
PubMed: 37802059
DOI: 10.1055/a-2159-6949 -
SLAS Discovery : Advancing Life... Oct 2023
Topics: Humans; Molecular Imaging
PubMed: 37821045
DOI: 10.1016/j.slasd.2023.10.001 -
Thoracic Surgery Clinics Aug 2023Intraoperative molecular imaging innovations have been propelled by the development of fluorescent contrast agents that specifically target tumor tissues and advanced... (Review)
Review
Intraoperative molecular imaging innovations have been propelled by the development of fluorescent contrast agents that specifically target tumor tissues and advanced camera systems that can detect the specified fluorescence. The most promising agent to date is OTL38, a targeted and near-infrared agent that was recently approved by the Food and Drug Administration for intraoperative imaging for lung cancer.
Topics: Humans; Lung Neoplasms; Fluorescent Dyes; Molecular Imaging; Optical Imaging
PubMed: 37414478
DOI: 10.1016/j.thorsurg.2023.04.013