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Radiology Nov 2023
Topics: Humans; Medical Oncology; Neoplasms; Molecular Imaging
PubMed: 37987660
DOI: 10.1148/radiol.231930 -
Current Opinion in Chemical Biology Aug 2019High-speed atomic force microscopy (HS-AFM) is a unique tool for molecular imaging. It can directly visualize protein molecules during their functional activity at high... (Review)
Review
High-speed atomic force microscopy (HS-AFM) is a unique tool for molecular imaging. It can directly visualize protein molecules during their functional activity at high spatiotemporal resolution, without a marker being attached to the molecules. Molecular dynamics filmed with HS-AFM can provide mechanistic insights into the functional molecular processes that are hard to be attained with other approaches. In this mini review, I highlight some of recent relevant studies of proteins by HS-AFM imaging after brief descriptions of AFM and HS-AFM.
Topics: Microscopy, Atomic Force; Molecular Dynamics Simulation; Molecular Imaging; Proteins
PubMed: 31254806
DOI: 10.1016/j.cbpa.2019.05.010 -
Nature Reviews. Nephrology Oct 2021In nephrology, differential diagnosis or assessment of disease activity largely relies on the analysis of glomerular filtration rate, urinary sediment, proteinuria and... (Review)
Review
In nephrology, differential diagnosis or assessment of disease activity largely relies on the analysis of glomerular filtration rate, urinary sediment, proteinuria and tissue obtained through invasive kidney biopsies. However, currently available non-invasive functional parameters, and most serum and urine biomarkers, cannot capture intrarenal molecular disease processes specifically. Moreover, although histopathological analyses of kidney biopsy samples enable the visualization of pathological morphological and molecular alterations, they only provide information about a small part of the kidney and do not allow longitudinal monitoring. These limitations not only hinder understanding of the dynamics of specific disease processes in the kidney, but also limit the targeting of treatments to active phases of disease and the development of novel targeted therapies. Molecular imaging enables non-invasive and quantitative assessment of physiological or pathological processes by combining imaging technologies with specific molecular probes. Here, we discuss current preclinical and clinical molecular imaging approaches in nephrology. Non-invasive visualization of the kidneys through molecular imaging can be used to detect and longitudinally monitor disease activity and can therefore provide companion diagnostics to guide clinical trials, as well as the safe and effective use of drugs.
Topics: Humans; Kidney Diseases; Molecular Imaging
PubMed: 34188207
DOI: 10.1038/s41581-021-00440-4 -
Methods in Molecular Biology (Clifton,... 2020Atomic force and transmission electron microscopies (AFM/TEM) are powerful tools to analyze RNA-based nanostructures. While cryo-TEM analysis allows the determination of...
Atomic force and transmission electron microscopies (AFM/TEM) are powerful tools to analyze RNA-based nanostructures. While cryo-TEM analysis allows the determination of near-atomic resolution structures of large RNA complexes, this chapter intends to present how RNA nanostructures can be analyzed at room temperature on surfaces. Indeed, TEM and AFM analyses permit the conformation of a large population of individual molecular structures to be observed, providing a statistical basis for the variability of these nanostructures within the population. Nevertheless, if double-stranded DNA molecular imaging has been described extensively, only a few investigations of single-stranded DNA and RNA filaments have been conducted so far. Indeed, technique for spreading and adsorption of ss-molecules on AFM surfaces or TEM grids is a crucial step to avoid disturbing RNA conformation on the surface. In this chapter, we present a specific method to analyze RNA assemblies and RNA-protein complexes for molecular microscopies.
Topics: Microscopy, Atomic Force; Microscopy, Electron, Transmission; Molecular Imaging; Nanostructures; Nucleic Acid Conformation; RNA; Ribonucleoproteins
PubMed: 32006322
DOI: 10.1007/978-1-0716-0278-2_20 -
JACC. Cardiovascular Imaging Nov 2020As therapeutic approaches have evolved from exogenous bone marrow cell delivery to pharmacological stimulation of endogenous repair, so too has imaging of cardiac repair... (Review)
Review
As therapeutic approaches have evolved from exogenous bone marrow cell delivery to pharmacological stimulation of endogenous repair, so too has imaging of cardiac repair made significant strides forward. Evaluation of functional outcome remains a staple of noninvasive clinical imaging, which can robustly quantify contractile function, perfusion, and tissue viability. Direct labeling of cells or other novel therapeutics visualizes the whole-body distribution and pharmacokinetics of the therapeutic agent, providing insights into retention, targeting, and drug-tissue interactions. And finally, targeted molecular imaging agents are emerging that may be specifically coupled to drugs targeting the same pathway. This approach enables interrogation of temporal and spatial changes at the molecular level underlying tissue degeneration and regeneration, which facilitates accurate patient selection and timing for therapeutic intervention, as exemplified by recent efforts focusing on the role of inflammation in cardiac repair. The concept of image-guided repair carves out an important and evolving niche for molecular imaging in cardiovascular medicine, with the potential not only to predict outcomes but also to improve patient stratification and progress toward personalized reparative therapy.
Topics: Heart; Humans; Molecular Imaging; Predictive Value of Tests; Radioisotopes
PubMed: 31864993
DOI: 10.1016/j.jcmg.2019.11.007 -
Journal of Nuclear Medicine : Official... Apr 2021Reactive oxygen species (ROS) play a pivotal role in many cellular processes and can be either beneficial or harmful. The design of ROS-sensitive fluorophores has... (Review)
Review
Reactive oxygen species (ROS) play a pivotal role in many cellular processes and can be either beneficial or harmful. The design of ROS-sensitive fluorophores has allowed for imaging of specific activity and has helped elucidate mechanisms of action for ROS. Understanding the oxidative role of ROS in the many roles it plays allows us to understand the human body. This review provides a concise overview of modern advances in the field of ROS imaging. Indeed, much has been learned about the role of ROS throughout the years; however, it has recently been shown that using nanoparticles, rather than individual small organic fluorophores, for ROS imaging can further our understanding of ROS.
Topics: Humans; Molecular Imaging; Reactive Oxygen Species
PubMed: 33384322
DOI: 10.2967/jnumed.120.245415 -
Seminars in Nuclear Medicine Jul 2020Molecular imaging with positron emission tomography (PET) and single-photon emission computed tomography (SPECT) serves numerous applications in clinical cardiology and... (Review)
Review
Molecular imaging with positron emission tomography (PET) and single-photon emission computed tomography (SPECT) serves numerous applications in clinical cardiology and research. Similar to other medical imaging technologies, this area has undergone and continues to experience rapid changes resulting from technological and medical advances. These have immediate impacts on diagnosis, treatment planning, and patient care, as well as supplying innovative tools for fundamental and translational research. A broad shift toward hybrid PET systems and incorporation of advanced computational tools has been accompanied by mechanism-specific, targeted radiopharmaceuticals that seek to address long-standing limitations in cardiac imaging. While this review addresses some of the still-emerging clinical uses of established radiopharmaceuticals, it too highlights newer imaging probes, applications, and imaging techniques and instrumentation on the horizon. We highlight molecular imaging advances in inflammatory and infiltrative myocardial conditions, heart metabolism, vascular and valvular diseases, neurohormonal dysregulation, and transformational technical advances such as the rise of artificial intelligence and theranostic approaches to cardiovascular disease.
Topics: Cardiovascular Diseases; Heart; Humans; Molecular Imaging
PubMed: 32540033
DOI: 10.1053/j.semnuclmed.2020.02.005 -
European Journal of Nuclear Medicine... Dec 2019Our understanding on human neurodegenerative disease was previously limited to clinical data and inferences about the underlying pathology based on histopathological... (Review)
Review
Our understanding on human neurodegenerative disease was previously limited to clinical data and inferences about the underlying pathology based on histopathological examination. Animal models and in vitro experiments have provided evidence for a cell-autonomous and a non-cell-autonomous mechanism for the accumulation of neuropathology. Combining modern neuroimaging tools to identify distinct neural networks (connectomics) with target-specific positron emission tomography (PET) tracers is an emerging and vibrant field of research with the potential to examine the contributions of cell-autonomous and non-cell-autonomous mechanisms to the spread of pathology. The evidence provided here suggests that both cell-autonomous and non-cell-autonomous processes relate to the observed in vivo characteristics of protein pathology and neurodegeneration across the disease spectrum. We propose a synergistic model of cell-autonomous and non-cell-autonomous accounts that integrates the most critical factors (i.e., protein strain, susceptible cell feature and connectome) contributing to the development of neuronal dysfunction and in turn produces the observed clinical phenotypes. We believe that a timely and longitudinal pursuit of such research programs will greatly advance our understanding of the complex mechanisms driving human neurodegenerative diseases.
Topics: Animals; Connectome; Humans; Molecular Imaging; Neurodegenerative Diseases
PubMed: 31292699
DOI: 10.1007/s00259-019-04394-5 -
International Journal of Molecular... Feb 2022Personalized medicine is emerging as a new goal in the diagnosis and treatment of diseases. This approach aims to establish differences between patients suffering from... (Review)
Review
Personalized medicine is emerging as a new goal in the diagnosis and treatment of diseases. This approach aims to establish differences between patients suffering from the same disease, which allows to choose the most effective treatment. Molecular imaging (MI) enables advanced insight into molecule interactions and disease pathology, improving the process of diagnosis and therapy and, for that reason, plays a crucial role in personalized medicine. Nanoparticles are widely used in MI techniques due to their size, high surface area to volume ratio, and multifunctional properties. After conjugation to specific ligands and drugs, nanoparticles can transport therapeutic compounds directly to their area of action and therefore may be used in theranostics-the simultaneous implementation of treatment and diagnostics. This review summarizes different MI techniques, including optical imaging, ultrasound imaging, magnetic resonance imaging, nuclear imaging, and computed tomography imaging with theranostics nanoparticles. Furthermore, it explores the potential use of constructs that enables multimodal imaging and track diseases in real time.
Topics: Drug Delivery Systems; Humans; Molecular Imaging; Multimodal Imaging; Nanoparticles; Nanotechnology
PubMed: 35269797
DOI: 10.3390/ijms23052658 -
Surgical Oncology Clinics of North... Apr 2020Neuroendocrine tumors of the gastrointestinal tract or pancreas are rare. Their presentation overlaps with other intra-abdominal neoplasms, but can have unique features.... (Review)
Review
Neuroendocrine tumors of the gastrointestinal tract or pancreas are rare. Their presentation overlaps with other intra-abdominal neoplasms, but can have unique features. The workup involves recognition of unusual clinical features associated with the tumors, imaging, analysis of blood or urine concentrations, and biopsy. Functional imaging takes advantage of the neuroendocrine tumor-specific expression of somatostatin receptors. There are characteristic features supporting the diagnosis on contrast-enhanced cross-sectional imaging. The use of tumor markers for biochemical diagnosis requires an understanding of the confounding variables affecting these assays. There are unique and specific immunohistochemical staining and grading requirements for appropriate diagnosis of these tumors.
Topics: Animals; Biomarkers, Tumor; Humans; Intestinal Neoplasms; Molecular Imaging; Neuroendocrine Tumors; Pancreatic Neoplasms; Stomach Neoplasms
PubMed: 32151354
DOI: 10.1016/j.soc.2019.10.002