MODELING THE GROWTH AND INVASION OF GLIOMAS, FROM SIMPLE TO COMPLEX: THE GOLDIE LOCKS PARADIGM

2008 ◽  
Vol 03 (01n02) ◽  
pp. 111-123 ◽  
Author(s):  
RUSSELL ROCKNE ◽  
ELLSWORTH C. ALVORD ◽  
P. J. REED ◽  
KRISTIN R. SWANSON
Keyword(s):  
Radial Growth ◽  
Culture Media ◽  
Resonance Imaging ◽  
Glioma Invasion ◽  
Clinical Behavior ◽  
Novel Method ◽  
Magnetic Resonance Imaging Mri ◽  
And Diffusion

As with all mathematical modeling, the scope of the question to be explored determines the scope of the most appropriate model. The case is no different for the modeling of primary brain tumors (gliomas), ranging from too simple, not accounting for the major feature of gliomas (extensive invasion), to too complicated, with too many variables and no easy way to translate from culture media in vitro to brain tissue in vivo. We settle on a "just right" approach which utilizes currently available magnetic resonance imaging (MRI) to estimate two defining characteristics, net rates of proliferation (ρ) and diffusion (D). Most importantly, these parameters are predictive of clinical behavior, and can be tailored to individual patients in vivo and in real time. These two rates combine to generate a linear radial growth pattern of the MRI visible portion of each glioma. Further, we introduce a novel method for the calculation of glioma invasion through grey and white matter.

scholarly journals Bioresorbable optical sensor systems for monitoring of intracranial pressure and temperature

2019 ◽  
Vol 5 (7) ◽  
pp. eaaw1899 ◽  
Author(s):  
Jiho Shin ◽  
Zhonghe Liu ◽  
Wubin Bai ◽  
Yonghao Liu ◽  
Ying Yan ◽  
...  
Keyword(s):  
Optical Sensors ◽  
Diagnostic Information ◽  
Resonance Imaging ◽  
Optical Components ◽  
Continuous Measurements ◽  
Fabry Perot ◽  
Magnetic Resonance Imaging Mri ◽  
Two Dimensional Photonic Crystal

Continuous measurements of pressure and temperature within the intracranial, intraocular, and intravascular spaces provide essential diagnostic information for the treatment of traumatic brain injury, glaucoma, and cardiovascular diseases, respectively. Optical sensors are attractive because of their inherent compatibility with magnetic resonance imaging (MRI). Existing implantable optical components use permanent, nonresorbable materials that must be surgically extracted after use. Bioresorbable alternatives, introduced here, bypass this requirement, thereby eliminating the costs and risks of surgeries. Here, millimeter-scale bioresorbable Fabry-Perot interferometers and two dimensional photonic crystal structures enable precise, continuous measurements of pressure and temperature. Combined mechanical and optical simulations reveal the fundamental sensing mechanisms. In vitro studies and histopathological evaluations quantify the measurement accuracies, operational lifetimes, and biocompatibility of these systems. In vivo demonstrations establish clinically relevant performance attributes. The materials, device designs, and fabrication approaches outlined here establish broad foundational capabilities for diverse classes of bioresorbable optical sensors.

scholarly journals In vitro and in vivo magnetic resonance imaging (MRI) detection of GFP through magnetization transfer contrast (MTC)

NeuroImage ◽  
2010 ◽  
Vol 50 (2) ◽  
pp. 375-382 ◽  
Author(s):  
Carlos J. Pérez-Torres ◽  
Cynthia A. Massaad ◽  
Susan G. Hilsenbeck ◽  
Faridis Serrano ◽  
Robia G. Pautler
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Magnetization Transfer ◽  
Resonance Imaging ◽  
Magnetization Transfer Contrast ◽  
Magnetic Resonance Imaging Mri

scholarly journals In Vivo Potential of Manganese Chelated Porphysomes as MRI Contrast Agents

2017 ◽  
Vol 3 (1) ◽  
pp. 47-53 ◽  
Author(s):  
Chris J. Zhang ◽  
Michael S. Valic ◽  
Juan Chen ◽  
Gang Zheng
Keyword(s):  
Mri Contrast Agents ◽  
Resonance Imaging ◽  
Mri Contrast ◽  
Metal Chelating ◽  
Particle Stability ◽  
Quenching Efficiency ◽  
Magnetic Resonance Imaging Mri ◽  
Porphyrin Moiety

Porphysome nanoparticles are composed of porphyrin-conjugated lipids. The attachment of the porphyrin moiety to each phospholipid confers novel properties to the liposome-like nanoparticle, allowing it to perform a variety of diagnostic and therapeutic applications. The metal chelating properties of porphyrin can be used to bind manganese (Mn), transforming the porphysome into a contrast agent for magnetic resonance imaging (MRI). Previous work has extensively characterized the properties of the Mn-porphysome. Herein, we build upon that work by demonstrating the bio-interactions of Mn-porphysomes in vitro to validate their study in vivo. Particle stability in serum was inferred from fluorescence quenching efficiency, and tolerability to cells was measured using an MTT assay. Mn-porphysomes remained >80% quenched after 14H and showed no toxicity to cells at concentrations below 125 mM. These preliminary results suggest that the porphysome may be used to enhance MRI contrast in vivo.

scholarly journals Effects of Gadolinium Deposits in the Cerebellum: Reviewing the Literature from In Vitro Laboratory Studies to In Vivo Human Investigations

2021 ◽  
Vol 18 (14) ◽  
pp. 7214
Author(s):  
Miski Aghnia Khairinisa ◽  
Winda Ariyani ◽  
Yoshito Tsushima ◽  
Noriyuki Koibuchi
Keyword(s):  
Diagnostic Yield ◽  
In Vivo Studies ◽  
Laboratory Studies ◽  
Resonance Imaging ◽  
Behavioral Alterations ◽  
Repeated Use ◽  
Magnetic Resonance Imaging Mri ◽  
The Brain

Gadolinium (Gd)-based contrast agents (GBCAs) are chemicals injected intravenously during magnetic resonance imaging (MRI) to enhance the diagnostic yield. The repeated use of GBCAs can cause their deposition in the brain, including the cerebellum. Such deposition may affect various cell subsets in the brain and consequently cause behavioral alterations due to neurotoxicity. Caution should thus be exercised in using these agents, particularly in patients who are more likely to have repeated enhanced MRIs during their lifespan. Further studies are required to clarify the toxicity of GBCAs, and potential mechanisms causing neurotoxicity have recently been reported. This review introduces the effects of GBCAs in the cerebellum obtained from in vitro and in vivo studies and considers the possible mechanisms of neurotoxicity involved.

Synthesis and Evaluation of a Biocompatible Macromolecular Gadolinium Compound as a Liver-Specific Contrast Agent for MRI

2017 ◽  
Vol 70 (3) ◽  
pp. 307 ◽  
Author(s):  
Youyang Zhan ◽  
Rong Xue ◽  
Mengchao Zhang ◽  
Chuanling Wan ◽  
Xiaojing Li ◽  
...  
Keyword(s):  
Contrast Agent ◽  
Mri Contrast Agent ◽  
Resonance Imaging ◽  
Mri Contrast ◽  
Gadolinium Chelate ◽  
Liver Specific Contrast Agent ◽  
Magnetic Resonance Imaging Mri ◽  
Gadolinium Compound

A new macromolecular biocompatible gadolinium chelate complex (PAI-N2-DOTA-Gd) as a liver-specific magnetic resonance imaging (MRI) contrast agent was synthesised and evaluated. An aspartic acid–isoleucine copolymer was chemically linked with Gd-DOTA via ethylenediamine to give PAI-N2-DOTA-Gd. In vitro, the T1-relaxivity of PAI-N2-DOTA-Gd (14.38 mmol–1⋅L⋅s–1, 0.5 T) was much higher than that of the clinically used Gd-DOTA (4.96 mmol–1⋅L⋅s–1, 0.5 T), with obvious imaging signal enhancement. In the imaging experiments in vivo, PAI-N2-DOTA-Gd exhibited good liver selectivity, and had a greater intensity enhancement (68.8 ± 5.6 %) and a longer imaging window time (30–70 min), compared to Gd-DOTA (21.1 ± 5.3 %, 10–30 min). Furthermore, the in vivo histological studies of PAI-N2-DOTA-Gd showed a low acute toxicity and desirable biocompatibility. The results of this study indicate that PAI-N2-DOTA-Gd is a feasible liver-specific contrast agent for MRI.

Gadolinium(III)-based Polymeric Magnetic Resonance Imaging Agents for Tumor Imaging

2018 ◽  
Vol 25 (25) ◽  
pp. 2910-2937 ◽  
Author(s):  
Guangyue Zu ◽  
Ye Kuang ◽  
Jingjin Dong ◽  
Yi Cao ◽  
Tingting Zhang ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Contrast Agents ◽  
Small Molecule ◽  
Tumor Imaging ◽  
Imaging Agents ◽  
Resonance Imaging ◽  
Magnetic Resonance Imaging Mri

Contrast agents (CAs) are widely used to improve the signal-noise ratio in the magnetic resonance imaging (MRI) examinations. The majority of MRI CAs used in clinic are gadolinium( III) (Gd(III)) chelates with low molecular weight. Compared with these small-molecule CAs, Gd(III)-based polymeric magnetic resonance imaging agents (i.e. macromolecular contrast agents, mCAs), prepared by conjugating small-molecule Gd(III) chelates onto macromolecules, possess high relaxivity and relative long blood circulation time, which are favorable for MRI examinations. In last decades, increasing attention was paid to the design of mCAs with various structures, and further evaluation of the MRI performance both in vitro and in vivo. Herein, we focus on the recent progress of mCAs, including structures, properties and applications. Meanwhile, this review also highlights the emerging MRI mCAs with smart response and multi-function: tumor microenvironment- stimulated MRI, multi-mode imaging and MRI-based theranostics.

scholarly journals MRI of the Colon in the Pharmaceutical Field: The Future before us

Pharmaceutics ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 146 ◽  
Author(s):  
Sarah Sulaiman ◽  
Luca Marciani
Keyword(s):  
Drug Delivery ◽  
Drug Formulation ◽  
Review Of The Literature ◽  
Resonance Imaging ◽  
Colonic Drug Delivery ◽  
Luminal Flow ◽  
Magnetic Resonance Imaging Mri ◽  
Colonic Environment

Oral solid drug formulation is the most common route for administration and it is vital to increase knowledge of the gastrointestinal physiological environment to understand dissolution and absorption processes and to develop reliable biorelevant in vitro tools. In particular, colon targeted drug formulations have raised the attention of pharmaceutical scientists because of the great potential of colonic drug delivery. However, the distal bowel is still a relatively understudied part of the gastrointestinal tract. Recently, magnetic resonance imaging (MRI) has been gaining an emerging role in studying the colon. This article provides a comprehensive; contemporary review of the literature on luminal MRI of the colonic environment of the last 15 years with specific focus on colon physiological dimensions; motility; chyme and fluids; transit and luminal flow. The work reviewed provides novel physiological insight that will have a profound impact on our understanding of the colonic environment for drug delivery and absorption and will ultimately help to raise the in vitro/in vivo relevance of computer simulations and bench models.

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