Significance: Although the lymphatic system is the second largest circulatory system in the body, there are limited techniques available for characterizing lymphatic vessel function. We report shortwave-infrared (SWIR) imaging for minimally invasive quantification of lymphatic circulation with superior contrast and resolution compared with near-infrared first window imaging.
Aim: We aim to study the lymphatic structure and function via SWIR fluorescence imaging.
Purpose: Vascular endothelium plays a central role in the pathogenesis of acute and chronic radiation injuries, yet the mechanisms which promote sustained endothelial dysfunction and contribute to late responding organ failure are unclear. We employed 2 window (> 1100 nm emission) Near-Infrared (NIR) imaging using indocyanine green (ICG) to track and define the role of the notch ligand Delta-like ligand 4 (Dll4) in mediating vascular injury in two late-responding radiosensitive organs: the lung and kidney.
Procedures: Consomic strains of female Salt Sensitive or SS (Dll4-high) and SS with 3 chromosome inherited from Brown Norway, SS.
Introduction: Radiation therapy for head and neck squamous cell carcinoma is constrained by radiotoxicity to normal tissue. We demonstrate 100 nm theranostic nanoparticles for image-guided radiation therapy planning and enhancement in rat head and neck squamous cell carcinoma models.
Methods: PEG conjugated theranostic nanoparticles comprising of Au nanorods coated with Gadolinium oxide layers were tested for radiation therapy enhancement in 2D cultures of OSC-19-GFP-luc cells, and orthotopic tongue xenografts in male immunocompromised Salt sensitive or SS rats via both intratumoral and intravenous delivery.
. In the current MR-Linac online adaptive workflow, air regions on the MR images need to be manually delineated for abdominal targets, and then overridden by air density for dose calculation. Auto-delineation of these regions is desirable for speed purposes, but poses a challenge, since unlike computed tomography, they do not occupy all dark regions on the image.
View Article and Find Full Text PDFPurpose: MRI-guided adaptive radiation therapy (MRgART), particularly daily online adaptive replanning (OLAR) can substantially improve radiation therapy delivery, however, it can be labor-intensive and time-consuming. Currently, the decision to perform OLAR for a treatment fraction is determined subjectively. In this work, we develop a machine learning algorithm based on structural similarity index measure (SSIM) and change in entropy to quickly and objectively determine whether OLAR is necessary for a daily MRI set.
View Article and Find Full Text PDFPurpose: Online adaptive replanning (OLAR) is generally labor-intensive and time-consuming during MRI-guided adaptive radiation therapy (MRgART). This work aims to develop a method to determine OLAR necessity during MRgART.
Methods: A machine learning classifier was developed to predict OLAR necessity based on wavelet multiscale texture features extracted from daily MRIs and was trained and tested with data from 119 daily MRI datasets acquired during MRgART for 24 pancreatic cancer patients treated on a 1.
Auto-delineation of air regions on daily MRI for MR-guided online adaptive radiotherapy (MRgOART) of abdominal tumors is challenging since the air packets occur randomly and their MR intensities can be similar to some other tissue types. This work reports a new method to auto-delineate air regions on MRI.The proposed method (named DIFF method) consists of (1) generating a combined volume, which is a union of the air-containing organs on a reference MR image offline, (2) transferringfrom the reference MR to a daily MR via DIR, (3) combining the transferredwith a region of high DIR inaccuracy, and (4) applying a threshold to the obtained final combined volume to generate the air volumes.
View Article and Find Full Text PDFHighly colloidal upconversion nanoparticles (UCNPs) were synthesized at low temperatures by the thermal decomposition process. The structure, morphology, crystallinity, surface chemistry, and optical properties were systematically optimized and studied through various spectroscopic techniques. X-ray diffraction (XRD) patterns have shown the formation of single-phase, highly purified, well-crystalline, hexagonal LaF NPs, while the TEM micrographs show small, irregular sizes, spherically shaped, and aggregated polycrystalline UCNPs with an average crystalline size of about 8-15 nm.
View Article and Find Full Text PDFRecent clinical cohort studies have highlighted that there is a three-fold greater SARS-Cov-2 infection risk in cancer patients, and overall mortality in individuals with tumours is increased by 41% with respect to general COVID-19 patients. Thus, access to therapeutics and intensive care is compromised for people with both diseases (comorbidity) and there is risk of delayed access to diagnosis. This comorbidity has resulted in extensive burden on the treatment of patients and health care system across the globe; moreover, mortality of hospitalized patients with comorbidity is reported to be 30% higher than for individuals affected by either disease.
View Article and Find Full Text PDFImpaired angiogenesis function in pulmonary artery endothelial cells (PAEC) contributes to persistent pulmonary hypertension of the newborn (PPHN). Decreased nitric oxide (NO) amounts in PPHN lead to impaired mitochondrial biogenesis and angiogenesis in the lung; the mechanisms remain unclear. We hypothesized that decreased cyclic guanosine monophosphate (cGMP)-PKG (protein kinase G) signaling downstream of NO leads to decreased mitochondrial biogenesis and angiogenesis in PPHN.
View Article and Find Full Text PDFTo develop a dynamic in vivo near-infrared (NIR) fluorescence imaging assay to quantify sequential changes in lung vascular permeability-surface area product (PS) in rodents. Dynamic NIR imaging methods for determining lung vascular permeability-surface area product were developed and tested on non-irradiated and 13 Gy irradiated rats with/without treatment with lisinopril, a radiation mitigator. A physiologically-based pharmacokinetic (PBPK) model of indocyanine green (ICG) pulmonary disposition was applied to in vivo imaging data and PS was estimated.
View Article and Find Full Text PDFThe aim of this study was to develop and evaluate a liposome formulation that deliver oxaliplatin under magnetic field stimulus in high concentration to alleviate the off-target effects in a rat model of colorectal liver metastases (CRLM). Hybrid liposome-magnetic nanoparticles loaded with Cy5.5 dye and oxaliplatin (L-NIR- FeO/OX) were synthesized by using thermal decomposition method.
View Article and Find Full Text PDFSecond near infrared (NIR-II) window fluorescence imaging between 1000 and 1700 nm with reduced scattering and autofluorescence and deep tissue light penetration allows early and non-invasive determination of vascular pathologies. Here, we demonstrate in vivo NIR-II imaging techniques for tracking hyperglycaemia-induced Intracerebral Hemorrhage (ICH) and Blood Brain Barrier (BBB) hyperpermeability in Cerebral Cavernous Malformation (CCM) deficient mice (CCM1+/-). We synthesised PEGylated AgS quantum dots (QDs) with a bright fluorescent emission peak centred at 1135 nm under an 808 nm NIR light for dynamic imaging of cerebral vasculature in mice and determined the development of ICH and BBB impairment in hyperglycaemic CCM1+/- mice.
View Article and Find Full Text PDFWe report the impact of notch-DLL4-based hereditary vascular heterogeneities on the enhanced permeation and retention (EPR) effect and plasmonic photothermal therapy response in tumors. : We generated two consomic rat strains with differing DLL4 expression on 3 chromosome. These strains were based on immunocompromised Salt-sensitive or SS (DLL4-high) and SS.
View Article and Find Full Text PDFDecreased angiogenesis contributes to persistent pulmonary hypertension of the newborn (PPHN); mechanisms remain unclear. AMPK (5'AMP activated protein kinase) is a key regulator of cell metabolism. We investigated the hypothesis that a decrease in AMPK function leads to mitochondrial dysfunction and altered balance of notch ligands delta-like 4 (DLL4) and Jagged 1 (Jag1) to impair angiogenesis in PPHN.
View Article and Find Full Text PDFPurpose: Spectral computed tomography (CT) material decomposition algorithms require accurate physics-based models or empirically derived models. This study investigates a machine learning algorithm and transfer learning techniques for Spectral CT imaging of K-edge contrast agents using simulated and experimental measurements.
Methods: A feed forward multilayer perceptron was implemented and trained on data acquired using a step wedge phantom containing acrylic, aluminum, and gadolinium materials.
Progress in nanomedicine has enabled the development of smart hybrid nanostructures (HNSs) for brain cancer theranostics, a novel platform that can diagnose the brain while concurrently beginning primary treatment, initiating secondary treatments where necessary, and monitoring the therapy response. These HNSs can release guest molecules/cargoes directly to brain tumors in response to external physical stimuli. Such physical stimulation is generally referred to as remote stimuli which can be externally applied examples include alternating magnetic field, visible or near-infrared light, ultrasound radiation, X-ray, and radiofrequency.
View Article and Find Full Text PDFWe report sub-100 nm optical/magnetic resonance (MR)/X-ray contrast-bearing theranostic nanoparticles (TNPs) for interventional image-guided photothermal therapy (PTT) of solid tumors. TNPs were composed of Au@GdO:Ln (Ln = Yb/Er) with X-ray contrast (∼486 HU; 10 NPs/mL, 0.167 nM) and MR contrast (∼1.
View Article and Find Full Text PDFVascular supply is a critical component of the tumor microenvironment (TME) and is essential for tumor growth and metastasis, yet the endogenous genetic modifiers that impact vascular function in the TME are largely unknown. To identify the host TME modifiers of tumor vascular function, we combined a novel genetic mapping strategy [Consomic Xenograft Model] with near-infrared (NIR) fluorescence imaging and multiparametric analysis of pharmacokinetic modeling. To detect vascular flow, an intensified cooled camera based dynamic NIR imaging system with 785 nm laser diode based excitation was used to image the whole-body fluorescence emission of intravenously injected indocyanine green dye.
View Article and Find Full Text PDFG-protein-coupled receptor 120 (GPR120), as a member of the rhodopsin family of G-protein-coupled receptors, has been shown to function as a sensor for dietary fat in the gustatory and digestive systems. Its specific role in the chemoreception of fatty acids, which is thought to be crucial in understanding the mechanism surrounding the control of fat intake and, accordingly, in the treatment of obesity, remains unclear. Here we report a novel surface-enhanced Raman spectroscopy (SERS)-fluorescence bimodal microscopic technique for detection and imaging of GPR120 in single living cells.
View Article and Find Full Text PDFIEEE Trans Nanobioscience
December 2017
Breast Cancer Res Treat
August 2017
Purpose: Multiple aspects of the tumor microenvironment (TME) impact breast cancer, yet the genetic modifiers of the TME are largely unknown, including those that modify tumor vascular formation and function.
Methods: To discover host TME modifiers, we developed a system called the Consomic/Congenic Xenograft Model (CXM). In CXM, human breast cancer cells are orthotopically implanted into genetically engineered consomic xenograft host strains that are derived from two parental strains with different susceptibilities to breast cancer.
Highly dispersible Eu-doped CaMoO@Au-nanorod hybrid nanoparticles (HNPs) exhibit optical properties, such as plasmon resonances in the near-infrared region at 790 nm and luminescence at 615 nm, offering multimodal capabilities: fluorescence imaging, surface-enhanced Raman spectroscopy (SERS) detection and photothermal therapy (PTT). HNPs were conjugated with a Raman reporter (4-mercaptobenzoic acid), showing a desired SERS signal (enhancement factor 5.0 × 10).
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