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Gd retention

Juyoung Park, Muna Aryal, Natalia Vykhodtseva, Yong-Zhi Zhang, Nathan McDannold
Drug delivery in brain tumors is challenging because of the presence of blood-brain barrier (BBB) and the blood-tumor barrier (BTB). Focused ultrasound (FUS) combined with microbubbles can enhance the permeability of the BTB in brain tumors, as well as disrupting the BBB in the surrounding tissue. In this study, dynamic contrast-enhanced Magnetic Resonance Imaging (DCE-MRI) was used to characterize FUS-induced permeability changes in a rat glioma model and in the normal brain and to investigate the relationship between these changes and the resulting concentration of the chemotherapy agent doxorubicin (DOX)...
October 11, 2016: Journal of Controlled Release: Official Journal of the Controlled Release Society
C C O'Sullivan, M Lindenberg, C Bryla, N Patronas, C J Peer, L Amiri-Kordestani, N Davarpanah, E M Gonzalez, M Burotto, P Choyke, S M Steinberg, D J Liewehr, W D Figg, T Fojo, S Balasubramaniam, S E Bates
PURPOSE: Improved therapies and imaging modalities are needed for the treatment of breast cancer brain metastases (BCBM). ANG1005 is a drug conjugate consisting of paclitaxel covalently linked to Angiopep-2, designed to cross the blood-brain barrier. We conducted a biomarker substudy to evaluate (18)F-FLT-PET for response assessment. METHODS: Ten patients with measurable BCBM received ANG1005 at a dose of 550 mg/m(2) IV every 21 days. Before and after cycle 1, patients underwent PET imaging with (18)F-FLT, a thymidine analog, retention of which reflects cellular proliferation, for comparison with gadolinium-contrast magnetic resonance imaging (Gd-MRI) in brain metastases detection and response assessment...
November 2016: Breast Cancer Research and Treatment
Yu-Erh Huang, Yu-Jie Huang, Mary Ko, Chien-Chin Hsu, Chih-Feng Chen
OBJECTIVE: Granulomatous diseases (GDs) can be metabolically active and indistinguishable from lung cancer on (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) imaging. Evaluation of solitary pulmonary lesions remains a diagnostic challenge in regions with endemic GD. This study sought to determine the efficacy of dual-time-point (DTP) (18)F-FDG PET/computed tomography (CT) imaging in diagnosing solitary pulmonary lesions from such regions. METHODS: A total of 50 patients with solitary pulmonary nodules or masses with confirmed histopathological diagnoses underwent DTP (18)F-FDG PET/CT imaging at 1 and 3 h after tracer injection...
August 4, 2016: Annals of Nuclear Medicine
Jeong Hee Yoon, Joon-Il Choi, Yong Yeon Jeong, Andrea Schenk, Longquan Chen, Hendrik Laue, So Yeon Kim, Jeong Min Lee
BACKGROUND & AIMS: This study aimed to determine whether the predicted remnant liver function on dynamic hepatocyte-specific contrast media-enhanced magnetic resonance (DHCE-MR) imaging correlates with the results of the indocyanin green retention test (ICG R15) after hepatic resection or radiofrequency ablation (RFA). METHODS: This prospective multicenter study was approved by the Institutional Review Boards of each hospital. Informed consents were obtained from all...
July 28, 2016: Journal of Hepatology
A Adhipatria P Kartamihardja, Takahito Nakajima, Satomi Kameo, Hiroshi Koyama, Yoshito Tsushima
OBJECTIVE: To investigate the distribution and clearance of retained gadolinium (Gd) in various parts of the brain after intravenously administering a Gd-based contrast agent (GBCA) in normal and renal failure mouse models. METHODS: Two different mouse models: normal (n = 12) and renal failure (n = 12) were used. Clinical GBCAs (Gd-DTPA-BMA, 5 mmol kg(-1), or Gd-DOTA, 5 mmol kg(-1)) were intravenously administered five times per week for 4 weeks...
October 2016: British Journal of Radiology
Chin-Chen Chang, Hsu-Cheng Huang, Kao-Lang Liu, Yao-Ming Wu, Jason J S Lee, Shu-Fen Jiang, Mao-Yuan M Su
OBJECTIVE: Using Gd-EOB-DTPA-enhanced MRI to assess liver function and validate with indocyanine green (ICG) tests and parenchymal cell volume (PCV). METHODS: Nineteen patients scheduled for operation were enrolled. Functional liver volume (FLV) was computed from 20min post-contrast images. ICG retention was measured in serum 15min after injection. The histological PCV was determined from resected liver specimen. RESULTS: FLV showed significantly correlated with ICG retention (ICG-R15: r=-0...
July 2016: Clinical Imaging
Esther Kneepkens, Adriana Fernandes, Klaas Nicolay, Holger Grüll
OBJECTIVES: Drug-loaded temperature-sensitive liposomes (TSLs) allow heat-triggered local drug delivery to tumors. When magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) is applied to heat up the tumor, corelease of a drug together with an MR contrast agent (CA) from TSLs allows for indirect imaging of the drug release with MR imaging. However, liposomal encapsulation of commonly used gadolinium (Gd)-based MR CAs leads to prolonged retention times in the liver and spleen, which could lead to a transmetallation and redistribution of Gd to other organs...
June 15, 2016: Investigative Radiology
Quan Jiang, Li Zhang, Guangliang Ding, Esmaeil Davoodi-Bojd, Qingjiang Li, Lian Li, Neema Sadry, Maiken Nedergaard, Michael Chopp, Zhenggang Zhang
The glymphatic system has recently been shown to clear brain extracellular solutes and abnormalities in glymphatic clearance system may contribute to both initiation and progression of neurological diseases. Despite that diabetes is known as a risk factor for vascular diseases, little is known how diabetes affects the glymphatic system. The current study is the first investigation of the effect of diabetes on the glymphatic system and the link between alteration of glymphatic clearance and cognitive impairment in Type-2 diabetes mellitus rats...
June 15, 2016: Journal of Cerebral Blood Flow and Metabolism
A Adhipatria P Kartamihardja, Takahito Nakajima, Satomi Kameo, Hiroshi Koyama, Yoshito Tsushima
OBJECTIVES: The aim of this study was to investigate the impact of impaired renal function on gadolinium (Gd) retention in various organs after Gd-based contrast agent injection. MATERIALS AND METHODS: After local animal care and review committee approval, 23 normal mice and 26 with renal failure were divided into 4 treatment groups (Gd-DTPA-BMA, 5 mmol/kg; Gd-DOTA, 5 mmol/kg; GdCl3, 0.02 mmol/kg; and saline, 250 μL). Each agent was intravenously administered on weekdays for 4 weeks...
October 2016: Investigative Radiology
Eric Lancelot
OBJECTIVES: Gadolinium-based contrast agents (GBCAs) have been used for years for magnetic resonance imaging examinations. Because of their rapid blood clearance, they were considered as very safe products until some of them were shown to induce nephrogenic systemic fibrosis in patients with renal failure and hypersignals on T1-weighted unenhanced brain scans of patients with normal renal function. To date, these adverse effects have been related almost exclusively to the use of low-stability linear agents, which are more prone to release free gadolinium...
May 11, 2016: Investigative Radiology
Jin Hee Na, Sangmin Lee, Heebeom Koo, Hyounkoo Han, Kyung Eun Lee, Seung Jin Han, Seung Hong Choi, Hyuncheol Kim, Seulki Lee, Ick Chan Kwon, Kuiwon Choi, Kwangmeyung Kim
Herein, we have synthesized Gd(iii)-encapsulated glycol chitosan nanoparticles (Gd(iii)-CNPs) for tumor-targeted T1-weighted magnetic resonance (MR) imaging. The T1 contrast agent, Gd(iii), was successfully encapsulated into 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-modified CNPs to form stable Gd(iii)-encapsulated CNPs (Gd(iii)-CNPs) with an average particle size of approximately 280 nm. The stable nanoparticle structure of Gd(iii)-CNPs is beneficial for liver tumor accumulation by the enhanced permeation and retention (EPR) effect...
May 5, 2016: Nanoscale
Ying Zhang, Toujun Zou, Mirong Guan, Mingming Zhen, Daiqin Chen, Xiangping Guan, Hongbin Han, Chunru Wang, Chunying Shu
A macromolecular magnetic resonance imaging (MRI) contrast agent was successfully synthesized by conjugating the gadolinium/1,4,7,10-tetraazacyclododecane-1,4,7-tetracetic acid complex (Gd-DO3A) with 6,6-phenyl-C61 butyric acid (PC61BA) and upon further modification with human serum albumin (HSA). The final product, PC61BA-(Gd-DO3A)/HSA, has a high stability and exhibits a much higher relaxivity (r1 = 89.1 mM(-1) s(-1) at 0.5 T, 300 K) than Gd-DO3A (r1 = 4.7 mM(-1) s(-1)) does under the same condition, producing the synergistic positive effect of HSA and C60 on the relaxivity of Gd-DO3A...
May 11, 2016: ACS Applied Materials & Interfaces
Moshe Rogosnitzky, Stacy Branch
Gadolinium chelates are widely used as contrast media for magnetic resonance imaging. The approved gadolinium-based contrast agents (GBCAs) have historically been considered safe and well tolerated when used at recommended dosing levels. However, for nearly a decade, an association between GBCA administration and the development of nephrogenic systemic fibrosis (NSF) has been recognized in patients with severe renal impairment. This has led to modifications in clinical practices aimed at reducing the potential and incidence of NSF development...
June 2016: Biometals: An International Journal on the Role of Metal Ions in Biology, Biochemistry, and Medicine
M L Lord, F E McNeill, J L Gräfe, M D Noseworthy, D R Chettle
Gadolinium (Gd) based contrast agents have been commonly used over the past three decades to improve contrast in magnetic resonance imaging. These complexes, originally thought to be stable and clear from the body shortly after administration, have been shown to dissociate to a small extent and deposit in organs such as bone. A safe and non-invasive method for measuring Gd in bone is necessary for further exploring Gd retention in the body following the administration of a contrast agent. A feasibility study using a K x-ray fluorescence (K-XRF) system to measure Gd in human tibias was investigated...
June 2016: Applied Radiation and Isotopes
Jinjin Shi, Binghua Wang, Zhaoyang Chen, Wei Liu, Jingjing Pan, Lin Hou, Zhenzhong Zhang
PURPOSE: To develop a multi-functional theranostic nanoplatform with increased tumor retention, improving antitumor efficacy and decreased side effects of chemotherapy drugs. METHODS: GO@Gd nanocomposites was synthesized via decorating gadolinium (Gd) nanoparticles (GdNP) onto graphene oxide (GO), and then functionalized by polyethylene glycol (PEG2000), folic acid (FA), a widely used tumor targeting molecule, was linked to GO@Gd-PEG, finally, doxorubicin (DOX) was loaded onto GO@Gd-PEG-FA and obtained a tumor-targeting drug delivery system (GO@Gd-PEG-FA/DOX)...
June 2016: Pharmaceutical Research
Francesca Garello, Sandip Vibhute, Serhat Gündüz, Nikos K Logothetis, Enzo Terreno, Goran Angelovski
Bioresponsive MRI contrast agents sensitive to Ca(II) fluctuations may play a critical role in the development of functional molecular imaging methods to study brain physiology or abnormalities in muscle contraction. A great challenge in their chemistry is the preparation of probes capable of inducing a strong signal variation that could be detected in a robust way. To this end, the incorporation of small molecular weight bioresponsive agents into nanocarriers can improve the overall properties in a few ways: (i) the agent can be delivered into the tissue of interest, increasing the local concentration; (ii) its biokinetic properties and retention time will improve; (iii) the high molecular weight and size of the nanocarrier may cause additional changes in the MRI signal and raise the chances for their detection in functional experiments...
April 11, 2016: Biomacromolecules
Juan Li, Wenjiang Yang, Rongli Cui, Dongliang Wang, Yanan Chang, Weihong Gu, Wenyan Yin, Xue Bai, Kui Chen, Lin Xia, Huan Geng, Gengmei Xing
Fullerenes (C60) and metallofullerenes (Gd@C82) have similar chemical structure, but the bio-effects of both fullerene-based materials are distinct in vivo. Tracking organic carbon-based materials such as C60 and Gd@C82 is difficult in vivo due to the high content of carbon element in the living tissues themselves. In this study, the biodistribution and metabolism of fullerenes (C60 and Gd@C82) radiolabeled with (64)Cu were observed by positron emission tomography (PET). (64)Cu-C60 and (64)Cu-Gd@C82 were prepared using 1, 4, 7, 10-tetrakis (carbamoylmethyl)-1, 4, 7, 10-tetra-azacyclodo-decanes grafted on carbon cages as a chelator for (64)Cu, and were obtained rapidly with high radiochemical yield (≥90%)...
April 15, 2016: Nanotechnology
Zhuxian Zhou, Zhen Han, Zheng-Rong Lu
The clinical application of nanoparticular Gd(III) based contrast agents for tumor molecular MRI has been hindered by safety concerns associated with prolonged tissue retention, although they can produce strong tumor enhancement. In this study, a targeted well-defined cyclodextrin-based nanoglobular contrast agent was developed through self-assembly driven by host-guest interactions for safe and effective cancer molecular MRI. Multiple β-cyclodextrins attached POSS (polyhedral oligomeric silsesquioxane) nanoglobule was used as host molecule...
April 2016: Biomaterials
Kai-Huang Chen, Kuan-Chang Chang, Ting-Chang Chang, Tsung-Ming Tsai, Shu-Ping Liang, Tai-Fa Young, Yong-En Syu, Simon M Sze
Bipolar switching resistance behaviors of the Gd:SiO2 resistive random access memory (RRAM) devices on indium tin oxide electrode by the low-temperature supercritical CO2-treated technology were investigated. For physical and electrical measurement results obtained, the improvement on oxygen qualities, properties of indium tin oxide electrode, and operation current of the Gd:SiO2 RRAM devices were also observed. In addition, the initial metallic filament-forming model analyses and conduction transferred mechanism in switching resistance properties of the RRAM devices were verified and explained...
December 2016: Nanoscale Research Letters
Marvin Birka, Jörg Roscher, Michael Holtkamp, Michael Sperling, Uwe Karst
Since the 1980s, the broad application of gadolinium(Gd)-based contrast agents for magnetic resonance imaging (MRI) has led to significantly increased concentrations of Gd in the aqueous environment. Little is known about the stability of these highly polar xenobiotics under environmental conditions, in wastewater and in drinking water treatment. Therefore, the stability of frequently applied Gd-based MRI contrast agents towards UV radiation was investigated. The hyphenation of hydrophilic interaction liquid chromatography (HILIC) with inductively coupled plasma mass spectrometry (ICP-MS) and of HILIC with electrospray ionization mass spectrometry (ESI-MS) provided quantitative elemental information as well as structural information...
March 15, 2016: Water Research
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