scholarly journals In Vivo Imaging of Biodegradable Implants and Related Tissue Biomarkers

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2348
Author(s):  
Leon Riehakainen ◽  
Chiara Cavallini ◽  
Paolo Armanetti ◽  
Daniele Panetta ◽  
Davide Caramella ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Imaging Techniques ◽  
Special Focus ◽  
Tissue Remodelling ◽  
Biodegradable Implant ◽  
Advantages And Disadvantages ◽  
Non Invasive ◽  
Positron Emission ◽  
Longitudinal Imaging

Non-invasive longitudinal imaging of osseointegration of bone implants is essential to ensure a comprehensive, physical and biochemical understanding of the processes related to a successful implant integration and its long-term clinical outcome. This study critically reviews the present imaging techniques that may play a role to assess the initial stability, bone quality and quantity, associated tissue remodelling dependent on implanted material, implantation site (surrounding tissues and placement depth), and biomarkers that may be targeted. An updated list of biodegradable implant materials that have been reported in the literature, from metal, polymer and ceramic categories, is provided with reference to the use of specific imaging modalities (computed tomography, positron emission tomography, ultrasound, photoacoustic and magnetic resonance imaging) suitable for longitudinal and non-invasive imaging in humans. The advantages and disadvantages of the single imaging modality are discussed with a special focus on preclinical imaging for biodegradable implant research. Indeed, the investigation of a new implant commonly requires histological examination, which is invasive and does not allow longitudinal studies, thus requiring a large number of animals for preclinical testing. For this reason, an update of the multimodal and multi-parametric imaging capabilities will be here presented with a specific focus on modern biomaterial research.

scholarly journals Clinical application of pet

2005 ◽  
Vol 48 (spe2) ◽  
pp. 179-183 ◽  
Author(s):  
Francisco Lomeña ◽  
Marina Soler
Keyword(s):  
Structural Information ◽  
Imaging Modality ◽  
Imaging Techniques ◽  
Neurological Diseases ◽  
Efficiency Ratio ◽  
Non Invasive ◽  
Positron Emission ◽  
Pet Ct ◽  
Magnetic Resonance Imaging Mri

Positron emission tomography (PET) is an imaging modality that gives information on tissue metabolism and functionalism, different from other imaging techniques like computed tomography (CT) and magnetic resonance imaging (MRI), which provide anatomical or structural information. PET has reached its development in biomedical research because of its capacity to use analogous compounds of many endogenous substance as tracers, and to measure, in vivo and in a non-invasive way, their consumption by the different organs and tissues of the mammalian body. Fluordeoxyglucose-F18 (FDG) PET has been proven to be a tracer adequate for clinical use in oncology and in many neurological diseases, with an excellent cost-efficiency ratio. The current PET-CT scanners can come to be the best tools for exploring patients who suffer from cancer.

scholarly journals Diagnosis of Pancreatic Ductal Adenocarcinoma by Immuno-Positron Emission Tomography

2021 ◽  
Vol 10 (6) ◽  
pp. 1151
Author(s):  
Ruth González-Gómez ◽  
Roberto A. Pazo-Cid ◽  
Luis Sarría ◽  
Miguel Ángel Morcillo ◽  
Alberto J. Schuhmacher
Keyword(s):  
Positron Emission Tomography ◽  
Pancreatic Ductal Adenocarcinoma ◽  
Imaging Techniques ◽  
Metastatic Tumor ◽  
Emission Tomography ◽  
Whole Body ◽  
Ductal Adenocarcinoma ◽  
Non Invasive ◽  
Positron Emission

Diagnosis of pancreatic ductal adenocarcinoma (PDAC) by current imaging techniques is useful and widely used in the clinic but presents several limitations and challenges, especially in small lesions that frequently cause radiological tumors infra-staging, false-positive diagnosis of metastatic tumor recurrence, and common occult micro-metastatic disease. The revolution in cancer multi-“omics” and bioinformatics has uncovered clinically relevant alterations in PDAC that still need to be integrated into patients’ clinical management, urging the development of non-invasive imaging techniques against principal biomarkers to assess and incorporate this information into the clinical practice. “Immuno-PET” merges the high target selectivity and specificity of antibodies and engineered fragments toward a given tumor cell surface marker with the high spatial resolution, sensitivity, and quantitative capabilities of positron emission tomography (PET) imaging techniques. In this review, we detail and provide examples of the clinical limitations of current imaging techniques for diagnosing PDAC. Furthermore, we define the different components of immuno-PET and summarize the existing applications of this technique in PDAC. The development of novel immuno-PET methods will make it possible to conduct the non-invasive diagnosis and monitoring of patients over time using in vivo, integrated, quantifiable, 3D, whole body immunohistochemistry working like a “virtual biopsy”.

scholarly journals Melanoma Biomarkers and Their Potential Application for In Vivo Diagnostic Imaging Modalities

2020 ◽  
Vol 21 (24) ◽  
pp. 9583
Author(s):  
Monica Hessler ◽  
Elmira Jalilian ◽  
Qiuyun Xu ◽  
Shriya Reddy ◽  
Luke Horton ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Imaging Techniques ◽  
High Specificity ◽  
Diagnostic Challenge ◽  
Skin Imaging ◽  
Non Invasive ◽  
Dermatology Clinic ◽  
Melanoma Diagnosis ◽  
Specificity And Sensitivity

Melanoma is the deadliest form of skin cancer and remains a diagnostic challenge in the dermatology clinic. Several non-invasive imaging techniques have been developed to identify melanoma. The signal source in each of these modalities is based on the alteration of physical characteristics of the tissue from healthy/benign to melanoma. However, as these characteristics are not always sufficiently specific, the current imaging techniques are not adequate for use in the clinical setting. A more robust way of melanoma diagnosis is to “stain” or selectively target the suspect tissue with a melanoma biomarker attached to a contrast enhancer of one imaging modality. Here, we categorize and review known melanoma diagnostic biomarkers with the goal of guiding skin imaging experts to design an appropriate diagnostic tool for differentiating between melanoma and benign lesions with a high specificity and sensitivity.

scholarly journals Tracking Transplanted Stem Cells Using Magnetic Resonance Imaging and the Nanoparticle Labeling Method in Urology

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Jae Heon Kim ◽  
Hong J. Lee ◽  
Yun Seob Song
Keyword(s):  
Magnetic Resonance Imaging ◽  
Stem Cells ◽  
Molecular Imaging ◽  
Magnetic Resonance ◽  
Imaging Modality ◽  
Imaging Techniques ◽  
Image Resolution ◽  
Imaging Method ◽  
Resonance Imaging

A reliablein vivoimaging method to localize transplanted cells and monitor their viability would enable a systematic investigation of cell therapy. Most stem cell transplantation studies have used immunohistological staining, which does not provide information about the migration of transplanted cellsin vivoin the same host. Molecular imaging visualizes targeted cells in a living host, which enables determining the biological processes occurring in transplanted stem cells. Molecular imaging with labeled nanoparticles provides the opportunity to monitor transplanted cells noninvasively without sacrifice and to repeatedly evaluate them. Among several molecular imaging techniques, magnetic resonance imaging (MRI) provides high resolution and sensitivity of transplanted cells. MRI is a powerful noninvasive imaging modality with excellent image resolution for studying cellular dynamics. Several types of nanoparticles including superparamagnetic iron oxide nanoparticles and magnetic nanoparticles have been used to magnetically label stem cells and monitor viability by MRI in the urologic field. This review focuses on the current role and limitations of MRI with labeled nanoparticles for tracking transplanted stem cells in urology.

scholarly journals News about the Role of Fluid and Imaging Biomarkers in Neurodegenerative Diseases

Biomedicines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 252
Author(s):  
Jacopo Meldolesi
Keyword(s):  
Neurodegenerative Diseases ◽  
Imaging Techniques ◽  
Imaging Biomarkers ◽  
Positron Emission ◽  
Specific Proteins ◽  
Great Relevance ◽  
The Brain ◽  
Positive Point

Biomarkers are molecules that are variable in their origin, nature, and mechanism of action; they are of great relevance in biology and also in medicine because of their specific connection with a single or several diseases. Biomarkers are of two types, which in some cases are operative with each other. Fluid biomarkers, started around 2000, are generated in fluid from specific proteins/peptides and miRNAs accumulated within two extracellular fluids, either the central spinal fluid or blood plasma. The switch of these proteins/peptides and miRNAs, from free to segregated within extracellular vesicles, has induced certain advantages including higher levels within fluids and lower operative expenses. Imaging biomarkers, started around 2004, are identified in vivo upon their binding by radiolabeled molecules subsequently revealed in the brain by positron emission tomography and/or other imaging techniques. A positive point for the latter approach is the quantitation of results, but expenses are much higher. At present, both types of biomarker are being extensively employed to study Alzheimer’s and other neurodegenerative diseases, investigated from the presymptomatic to mature stages. In conclusion, biomarkers have revolutionized scientific and medical research and practice. Diagnosis, which is often inadequate when based on medical criteria only, has been recently improved by the multiplicity and specificity of biomarkers. Analogous results have been obtained for prognosis. In contrast, improvement of therapy has been limited or fully absent, especially for Alzheimer’s in which progress has been inadequate. An urgent need at hand is therefore the progress of a new drug trial design together with patient management in clinical practice.

scholarly journals Cre/lox-assisted non-invasive in vivo tracking of specific cell populations by positron emission tomography

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Martin Thunemann ◽  
Barbara F. Schörg ◽  
Susanne Feil ◽  
Yun Lin ◽  
Jakob Voelkl ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Emission Tomography ◽  
Cell Populations ◽  
Specific Cell ◽  
Non Invasive ◽  
Positron Emission

scholarly journals Study of Osteocyte Behavior by High-Resolution Intravital Imaging Following Photo-Induced Ischemia

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2874
Author(s):  
Hengfeng Yuan ◽  
Wen Jiang ◽  
Yuanxin Chen ◽  
Betty Kim
Keyword(s):  
Imaging Techniques ◽  
Avascular Osteonecrosis ◽  
Functional Changes ◽  
Cellular Processes ◽  
Non Invasive ◽  
Behavioral Dynamics ◽  
Bony Anatomy ◽  
Magnetic Resonance Imaging Mri

Ischemic injuries and local hypoxia can result in osteocytes dysfunction and play a key role in the pathogenesis of avascular osteonecrosis. Conventional imaging techniques including magnetic resonance imaging (MRI) and computed tomography (CT) can reveal structural and functional changes within bony anatomy; however, characterization of osteocyte behavioral dynamics in the setting of osteonecrosis at the single cell resolution is limited. Here, we demonstrate an optical approach to study real-time osteocyte functions in vivo. Using nicotinamide adenine dinucleotide (NADH) as a biomarker for metabolic dynamics in osteocytes, we showed that NADH level within osteocytes transiently increase significantly after local ischemia through non-invasive photo-induced thrombosis of afferent arterioles followed by a steady decline. Our study presents a non-invasive optical approach to study osteocyte behavior through the modulation of local environmental conditions. Thus it provides a powerful toolkit to study cellular processes involved in bone pathologies in vivo.

scholarly journals Non-invasive imaging of the coronary arteries

2018 ◽  
Vol 40 (29) ◽  
pp. 2444-2454 ◽  
Author(s):  
Philip D Adamson ◽  
David E Newby
Keyword(s):  
Coronary Arteries ◽  
Randomized Clinical Trials ◽  
Rapid Development ◽  
Current Status ◽  
Future Research ◽  
Research Perspective ◽  
Non Invasive ◽  
Positron Emission ◽  
Prognostic Stratification

Abstract Non-invasive imaging of the coronary arteries is an enterprise in rapid development. From the research perspective, there is great demand for in vivo techniques that can reliably identify features of high-risk plaque that may offer insight into pathophysiological processes and act as surrogate indicators of response to therapeutic intervention. Meanwhile, there is clear clinical need for greater accuracy in diagnosis and prognostic stratification. Fortunately, ongoing technological improvements and emerging data from randomized clinical trials are helping make these elusive goals a reality. This review provides an update on the current status of non-invasive coronary imaging with computed tomography, magnetic resonance, and positron emission tomography with a focus on current clinical applications and future research directions.

In vivo and freeze-trapped assays of the energy state of brain and skeletal tissues

1980 ◽  
Vol 289 (1037) ◽  
pp. 457-457
Keyword(s):  
Energy State ◽  
Creatine Phosphate ◽  
Time Range ◽  
Damage Potential ◽  
Range Resolution ◽  
Non Invasive ◽  
Body Tissues ◽  
Positron Emission ◽  
Averaging Time

Non-invasive, non-destructive assay of energy-related metabolic activity of body tissues is the goal of several biophysical approaches, surface fluorometry of mitochondrial flavoprotein, positron emission tomography and 31 P n.m.r. Each has an appropriate specificity, time range, resolution and tissue damage potential. 31 P n.m.r. is the least invasive and at 72 MHz, with a 20 min averaging time and a 20 mm bore magnet, it affords in vivo assay of energy related compounds of tissues in small animals, such as fish skeletal muscle (loach) and heads of adult mouse and of newborn gerbils. In the transition from normoxia and nitrogen anoxia, decreases of the creatine phosphate : inorganic phosphate ratios from 3.9, 5.0, 2.7 in normoxia to 1.2, 0.04, 0.06 in anoxia occur in fish, mouse and gerbil respectively. The remarkable retention of significant ATP levels (80% of normoxic) in the new-born gerbil through 20 min of N 2 anoxia is clearly demonstrated. Evidence for the origin of much of the in vivo signal from the mouse brain is afforded by the fast freeze-trapping, excision of brain and assay by cryo-n.m.r. (Chance, B. et al . 1978 Proc. natn. Acad. Sci. U.S.A. 75, 4925-4929) at —12 °C, the lowest temperature at which tissue signals are observed.

Sign in / Sign up

Export Citation Format

Share Document