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The New Phytologist Jun 2023Cuticles are multifunctional hydrophobic biocomposites that protect the aerial organs of plants. During plant development, plant cuticles must accommodate different...
Cuticles are multifunctional hydrophobic biocomposites that protect the aerial organs of plants. During plant development, plant cuticles must accommodate different mechanical constraints combining extensibility and stiffness, and the corresponding relationships with their architecture are unknown. Recent data showed a fine-tuning of cuticle architecture during fruit development, with several chemical clusters which raise the question of how they impact the mechanical properties of cuticles. We investigated the in-depth nanomechanical properties of tomato (Solanum lycopersicum) fruit cuticle from early development to ripening, in relation to chemical and structural heterogeneities by developing a correlative multimodal imaging approach. Unprecedented sharps heterogeneities were evidenced including an in-depth mechanical gradient and a 'soft' central furrow that were maintained throughout the plant development despite the overall increase in elastic modulus. In addition, we demonstrated that these local mechanical areas are correlated to chemical and structural gradients. This study shed light on fine-tuning of mechanical properties of cuticles through the modulation of their architecture, providing new insight for our understanding of structure-function relationships of plant cuticles and for the design of bioinspired material.
Topics: Multimodal Imaging; Fruit
PubMed: 36869436
DOI: 10.1111/nph.18862 -
International Journal of Nanomedicine 2021Recently, the demand for hybrid PET/MRI imaging techniques has increased significantly, which has sparked the investigation into new ways to simultaneously track... (Review)
Review
Recently, the demand for hybrid PET/MRI imaging techniques has increased significantly, which has sparked the investigation into new ways to simultaneously track multiple molecular targets and improve the localization and expression of biochemical markers. Multimodal imaging probes have recently emerged as powerful tools for improving the detection sensitivity and accuracy-both important factors in disease diagnosis and treatment; however, only a limited number of bimodal probes have been investigated in preclinical models. Herein, we briefly describe the strengths and limitations of PET and MRI modalities and highlight the need for the development of multimodal molecularly-targeted agents. We have tried to thoroughly summarize data on bimodal probes available on PubMed. Emphasis was placed on their design, safety profiles, pharmacokinetics, and clearance properties. The challenges in PET/MR probe development using a number of illustrative examples are also discussed, along with future research directions for these novel conjugates.
Topics: Magnetic Resonance Imaging; Multimodal Imaging; Positron-Emission Tomography
PubMed: 35002239
DOI: 10.2147/IJN.S336299 -
Cancer Imaging : the Official... Jun 2020Oncological diseases account for a significant portion of the burden on public healthcare systems with associated costs driven primarily by complex and long-lasting... (Review)
Review
Oncological diseases account for a significant portion of the burden on public healthcare systems with associated costs driven primarily by complex and long-lasting therapies. Through the visualization of patient-specific morphology and functional-molecular pathways, cancerous tissue can be detected and characterized non-invasively, so as to provide referring oncologists with essential information to support therapy management decisions. Following the onset of stand-alone anatomical and functional imaging, we witness a push towards integrating molecular image information through various methods, including anato-metabolic imaging (e.g., PET/CT), advanced MRI, optical or ultrasound imaging.This perspective paper highlights a number of key technological and methodological advances in imaging instrumentation related to anatomical, functional, molecular medicine and hybrid imaging, that is understood as the hardware-based combination of complementary anatomical and molecular imaging. These include novel detector technologies for ionizing radiation used in CT and nuclear medicine imaging, and novel system developments in MRI and optical as well as opto-acoustic imaging. We will also highlight new data processing methods for improved non-invasive tissue characterization. Following a general introduction to the role of imaging in oncology patient management we introduce imaging methods with well-defined clinical applications and potential for clinical translation. For each modality, we report first on the status quo and, then point to perceived technological and methodological advances in a subsequent status go section. Considering the breadth and dynamics of these developments, this perspective ends with a critical reflection on where the authors, with the majority of them being imaging experts with a background in physics and engineering, believe imaging methods will be in a few years from now.Overall, methodological and technological medical imaging advances are geared towards increased image contrast, the derivation of reproducible quantitative parameters, an increase in volume sensitivity and a reduction in overall examination time. To ensure full translation to the clinic, this progress in technologies and instrumentation is complemented by advances in relevant acquisition and image-processing protocols and improved data analysis. To this end, we should accept diagnostic images as "data", and - through the wider adoption of advanced analysis, including machine learning approaches and a "big data" concept - move to the next stage of non-invasive tumour phenotyping. The scans we will be reading in 10 years from now will likely be composed of highly diverse multi-dimensional data from multiple sources, which mandate the use of advanced and interactive visualization and analysis platforms powered by Artificial Intelligence (AI) for real-time data handling by cross-specialty clinical experts with a domain knowledge that will need to go beyond that of plain imaging.
Topics: Artificial Intelligence; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Medical Oncology; Multimodal Imaging; Neoplasms; Radionuclide Imaging; Ultrasonography
PubMed: 32517801
DOI: 10.1186/s40644-020-00312-3 -
The British Journal of Radiology Aug 2017Breast metastases from extramammary cancers are rare and usually related to poor prognosis. The extramammary tumours most frequently exhibiting breast metastases are... (Review)
Review
Breast metastases from extramammary cancers are rare and usually related to poor prognosis. The extramammary tumours most frequently exhibiting breast metastases are melanoma, lymphomas, ovarian cancer, lung and neuroendocrine tumours, and sarcomas. Owing to the lack of reliable and specific clinical or radiological signs for the diagnosis of breast metastases, a combination of techniques is needed to differentiate these lesions from primary breast carcinoma or even benign breast lesions. Multiple imaging methods may be used to evaluate these patients, including mammography, ultrasound, MRI, CT and positron emission tomography CT. Clinical and imaging manifestations are varied, depend on the form of dissemination of the disease and may mimic primary benign and malignant breast lesions. Haematologically disseminated metastases often develop as a circumscribed mass, whereas lymphatic dissemination often presents as diffuse breast oedema and skin thickening. Unlike primary carcinomas, breast metastases generally do not have spiculated margins, skin or nipple retraction. Microlobulated or indistinct margins may be present in some cases. Although calcifications are not frequently present in metastatic lesions, they occur more commonly in patients with ovarian cancer. Although rare, secondary malignant neoplasms should be considered in the differential diagnosis of breast lesions, in the appropriate clinical setting. Knowledge of the most common imaging features can help to provide the correct diagnosis and adequate therapeutic planning.
Topics: Breast; Breast Neoplasms; Female; Humans; Magnetic Resonance Imaging; Mammography; Multimodal Imaging; Neoplasms, Second Primary; Positron Emission Tomography Computed Tomography; Tomography, X-Ray Computed; Ultrasonography, Mammary
PubMed: 28485985
DOI: 10.1259/bjr.20170197 -
Radiation Oncology (London, England) Aug 2018For 2018, the American Cancer Society estimated that there would be approximately 1.7 million new diagnoses of cancer and about 609,640 cancer-related deaths in the...
For 2018, the American Cancer Society estimated that there would be approximately 1.7 million new diagnoses of cancer and about 609,640 cancer-related deaths in the United States. By 2030 these numbers are anticipated to exceed a staggering 21 million annual diagnoses and 13 million cancer-related deaths. The three primary therapeutic modalities for cancer treatments are surgery, chemotherapy, and radiation therapy. Individually or in combination, these treatment modalities have provided and continue to provide curative and palliative care to the myriad victims of cancer.Today, CT-based treatment planning is the primary means through which conventional photon radiation therapy is planned. Although CT remains the primary treatment planning modality, the field of radiation oncology is moving beyond the sole use of CT scans to define treatment targets and organs at risk. Complementary tissue scans, such as magnetic resonance imaging (MRI) and positron electron emission (PET) scans, have all improved a physician's ability to more specifically identify target tissues, and in some cases, international guidelines have even been issued. Moreover, efforts to combine PET and MR to define solid tumors for radiotherapy planning and treatment evaluation are also gaining traction.Keeping these advances in mind, we present brief overviews of other up-and-coming key imaging concepts that appear promising for initial treatment target definition or treatment response from radiation therapy.
Topics: Animals; Contrast Media; Diagnostic Imaging; Electromagnetic Phenomena; Fluorescent Dyes; Humans; Magnetic Resonance Imaging; Mice; Microscopy; Multimodal Imaging; Positron-Emission Tomography; Radiation Oncology; Spectrometry, Fluorescence; Spectroscopy, Near-Infrared; Spectrum Analysis, Raman; Tomography, X-Ray Computed; Treatment Outcome; Ultrasonography
PubMed: 30103786
DOI: 10.1186/s13014-018-1091-1 -
PloS One 2017Fluorescence imaging is a powerful technique with diverse applications in intraoperative settings. Visualization of three dimensional (3D) structures and depth...
Fluorescence imaging is a powerful technique with diverse applications in intraoperative settings. Visualization of three dimensional (3D) structures and depth assessment of lesions, however, are oftentimes limited in planar fluorescence imaging systems. In this study, a novel Fluorescence Imaging Topography Scanning (FITS) system has been developed, which offers color reflectance imaging, fluorescence imaging and surface topography scanning capabilities. The system is compact and portable, and thus suitable for deployment in the operating room without disturbing the surgical flow. For system performance, parameters including near infrared fluorescence detection limit, contrast transfer functions and topography depth resolution were characterized. The developed system was tested in chicken tissues ex vivo with simulated tumors for intraoperative imaging. We subsequently conducted in vivo multimodal imaging of sentinel lymph nodes in mice using FITS and PET/CT. The PET/CT/optical multimodal images were co-registered and conveniently presented to users to guide surgeries. Our results show that the developed system can facilitate multimodal intraoperative imaging.
Topics: Animals; Chickens; Lymph Nodes; Mice; Monitoring, Intraoperative; Multimodal Imaging; Optical Imaging; Positron Emission Tomography Computed Tomography
PubMed: 28437441
DOI: 10.1371/journal.pone.0174928 -
The British Journal of Radiology Jan 2021Cardiovascular imaging has significantly evolved since the turn of the century. Progress in the last two decades has been marked by advances in every modality used to... (Review)
Review
Cardiovascular imaging has significantly evolved since the turn of the century. Progress in the last two decades has been marked by advances in every modality used to image the heart, including echocardiography, cardiac magnetic resonance, cardiac CT and nuclear cardiology. There has also been a dramatic increase in hybrid and fusion modalities that leverage the unique capabilities of two imaging techniques simultaneously, as well as the incorporation of artificial intelligence and machine learning into the clinical workflow. These advances in non-invasive cardiac imaging have guided patient management and improved clinical outcomes. The technological developments of the past 20 years have also given rise to new imaging subspecialities and increased the demand for dedicated cardiac imagers who are cross-trained in multiple modalities. This state-of-the-art review summarizes the evolution of multimodality cardiac imaging in the 21st century and highlights opportunities for future innovation.
Topics: Cardiac Imaging Techniques; Humans; Multimodal Imaging
PubMed: 33237824
DOI: 10.1259/bjr.20200780 -
The British Journal of Radiology Aug 2017Since 2010 the portfolio of positron emission tomography (PET)-based imaging has been expanded by industry with the introduction of combined whole-body PET/MRI systems... (Review)
Review
Since 2010 the portfolio of positron emission tomography (PET)-based imaging has been expanded by industry with the introduction of combined whole-body PET/MRI systems with the intent of merging PET-based molecular imaging with the strengths of MRI. PET/MRI has created a lot of hype in the scientific community but comparatively little traction in the clinic. The first years of whole-body PET/MRI were used to address inherent technical challenges; however, it is now time to make use of the full potential of this integrated imaging modality. This opinion piece highlights the continuing challenges for the clinical adoption of PET/MRI and cautions against putting too much emphasis on comparisons with clinical PET/CT. In order for PET/MRI to enter clinical practice, cross-specialty co-operation must be pursued with rigour and use-case scenarios must be propagated, following long-awaited expansion of reimbursement strategies and protocol standardization.
Topics: Humans; Magnetic Resonance Imaging; Multimodal Imaging; Positron-Emission Tomography; Whole Body Imaging
PubMed: 28707543
DOI: 10.1259/bjr.20170347 -
EBioMedicine Jul 2021Gastric inflammation is a major risk factor for gastric cancer. Current endoscopic methods are not able to efficiently detect and characterize gastric inflammation,... (Clinical Trial)
Clinical Trial
BACKGROUND
Gastric inflammation is a major risk factor for gastric cancer. Current endoscopic methods are not able to efficiently detect and characterize gastric inflammation, leading to a sub-optimal patients' care. New non-invasive methods are needed. Reflectance mucosal light analysis is of particular interest in this context. The aim of our study was to analyze reflectance light and specific autofluorescence signals, both in humans and in a mouse model of gastritis.
METHODS
We recruited patients undergoing gastroendoscopic procedure during which reflectance was analysed with a multispectral camera. In parallel, the gastritis mouse model of Helicobacter pylori infection was used to investigate reflectance from ex vivo gastric samples using a spectrometer. In both cases, autofluorescence signals were measured using a confocal microscope.
FINDINGS
In gastritis patients, reflectance modifications were significant in near-infrared spectrum, with a decrease between 610 and 725 nm and an increase between 750 and 840 nm. Autofluorescence was also modified, showing variations around 550 nm of emission. In H. pylori infected mice developing gastric inflammatory lesions, we observed significant reflectance modifications 18 months after infection, with increased intensity between 617 and 672 nm. Autofluorescence was significantly modified after 1, 3 and 6 months around 550 and 630 nm. Both in human and in mouse, these reflectance data can be considered as biomarkers and accurately predicted inflammatory state.
INTERPRETATION
In this pilot study, using a practical measuring device, we identified in humans, modification of reflectance spectra in the visible spectrum and for the first time in near-infrared, associated with inflammatory gastric states. Furthermore, both in the mouse model and humans, we also observed modifications of autofluorescence associated with gastric inflammation. These innovative data pave the way to deeper validation studies on larger cohorts, for further development of an optical biopsy system to detect gastritis and finally to better surveil this important gastric cancer risk factor.
FUNDING
The project was funded by the ANR EMMIE (ANR-15-CE17-0015) and the French Gastroenterology Society (SNFGE).
Topics: Adult; Aged; Animals; Female; Fluorescence; Gastritis; Gastroscopy; Helicobacter pylori; Humans; Male; Mice; Mice, Inbred C57BL; Middle Aged; Multimodal Imaging; Optical Imaging; Video Recording
PubMed: 34229278
DOI: 10.1016/j.ebiom.2021.103462 -
Current Topics in Medicinal Chemistry 2015Aptamers are single-stranded oligonucleotides with high affinity and specificity to the target molecules or cells, thus they can serve as an important category of... (Review)
Review
Aptamers are single-stranded oligonucleotides with high affinity and specificity to the target molecules or cells, thus they can serve as an important category of molecular targeting ligand. Since their discovery, aptamers have been rapidly translated into clinical practice. The strong target affinity/selectivity, cost-effectivity, chemical versatility and safety of aptamers are superior to traditional peptides- or proteins-based ligands which make them unique choices for molecular imaging. Therefore, aptamers are considered to be extremely useful to guide various imaging contrast agents to the target tissues or cells for optical, magnetic resonance, nuclear, computed tomography, ultrasound and multimodality imaging. This review aims to provide an overview of aptamers' advantages as targeting ligands and their application in targeted imaging. Further research in synthesis of new types of aptamers and their conjugation with new categories of contrast agents is required to develop clinically translatable aptamer-based imaging agents which will eventually result in improved patient care.
Topics: Animals; Aptamers, Nucleotide; Contrast Media; Drug Delivery Systems; Fluorescent Dyes; Humans; Ligands; Magnetic Resonance Imaging; Mice; Molecular Imaging; Molecular Targeted Therapy; Multimodal Imaging; Neoplasms; Optical Imaging; SELEX Aptamer Technique; Tomography, X-Ray Computed
PubMed: 25866268
DOI: 10.2174/1568026615666150413153400