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Hackbarth S, Gao S, Šubr V, Lin L, Pohl J, Etrych T, Fang J. Singlet Oxygen In Vivo: It Is All about Intensity-Part 2. J Pers Med 2023; 13:jpm13050781. [PMID: 37240951 DOI: 10.3390/jpm13050781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/25/2023] [Accepted: 04/26/2023] [Indexed: 05/28/2023] Open
Abstract
Recently, we reported induced anoxia as a limiting factor for photodynamic tumor therapy (PDT). This effect occurs in vivo if the amount of generated singlet oxygen that undergoes chemical reactions with cellular components exceeds the local oxygen supply. The amount of generated singlet oxygen depends mainly on photosensitizer (PS) accumulation, efficiency, and illumination intensity. With illumination intensities above a certain threshold, singlet oxygen is limited to the blood vessel and the nearest vicinity; lower intensities allow singlet oxygen generation also in tissue which is a few cell layers away from the vessels. While all experiments so far were limited to light intensities above this threshold, we report experimental results for intensities at both sides of the threshold for the first time, giving proof for the described model. Using time-resolved optical detection in NIR, we demonstrate characteristic, illumination intensity-dependent changes in signal kinetics of singlet oxygen and photosensitizer phosphorescence in vivo. The described analysis allows for better optimization and coordination of PDT drugs and treatment, as well as new diagnostic methods based on gated PS phosphorescence, for which we report a first in vivo feasibility test.
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Affiliation(s)
- Steffen Hackbarth
- Institute of Physics, Photobiophysics, Humboldt University of Berlin, Newtonstr. 15, 12489 Berlin, Germany
| | - Shanghui Gao
- Laboratory of Microbiology and Oncology, Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan
| | - Vladimír Šubr
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovského nám. 2, 16200 Prague, Czech Republic
| | - Lisheng Lin
- Institute of Physics, Photobiophysics, Humboldt University of Berlin, Newtonstr. 15, 12489 Berlin, Germany
- Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou 350007, China
| | - Jakob Pohl
- Institute of Physics, Photobiophysics, Humboldt University of Berlin, Newtonstr. 15, 12489 Berlin, Germany
| | - Tomáš Etrych
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovského nám. 2, 16200 Prague, Czech Republic
| | - Jun Fang
- Laboratory of Microbiology and Oncology, Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan
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2
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Zhang Q, Gerweck LE, Cascio E, Yang Q, Huang P, Niemierko A, Bertolet A, Nesteruk KP, McNamara A, Schuemann J. Proton FLASH effects on mouse skin at different oxygen tensions. Phys Med Biol 2023; 68:10.1088/1361-6560/acb888. [PMID: 36731139 PMCID: PMC11164666 DOI: 10.1088/1361-6560/acb888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 02/02/2023] [Indexed: 02/04/2023]
Abstract
Objective. Irradiation at FLASH dose rates (>40 Gy s-1) has received great attention due to its reported normal tissue sparing effect. The FLASH effect was originally observed in electron irradiations but has since been shown to also occur with both photon and proton beams. Several mechanisms have been proposed to explain the tissue sparing at high dose rates, including effects involving oxygen, such as depletion of oxygen within the irradiated cells. In this study, we investigated the protective role of FLASH proton irradiation on the skin when varying the oxygen concentration.Approach. Our double scattering proton system provided a 1.2 × 1.6 cm2elliptical field at a dose rate of ∼130 Gy s-1. The conventional dose rate was ∼0.4 Gy s-1. The legs of the FVB/N mice were marked with two tattooed dots and fixed in a holder for exposure. To alter the skin oxygen concentration, the mice were breathing pure oxygen or had their legs tied to restrict blood flow. The distance between the two dots was measured to analyze skin contraction over time.Main results. FLASH irradiation mitigated skin contraction by 15% compared to conventional dose rate irradiation. The epidermis thickness and collagen deposition at 75 d following 25 to 30 Gy exposure suggested a long-term protective function in the skin from FLASH irradiation. Providing the mice with oxygen or reducing the skin oxygen concentration removed the dose-rate-dependent difference in response.Significance. FLASH proton irradiation decreased skin contraction, epidermis thickness and collagen deposition compared to standard dose rate irradiations. The observed oxygen-dependence of the FLASH effect is consistent with, but not conclusive of, fast oxygen depletion during the exposure.
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Affiliation(s)
- Qixian Zhang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Leo E Gerweck
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Ethan Cascio
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Qingyuan Yang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Peigen Huang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Andrzej Niemierko
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Alejandro Bertolet
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Konrad Pawel Nesteruk
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Aimee McNamara
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Jan Schuemann
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
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3
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Singlet Oxygen In Vivo: It Is All about Intensity. J Pers Med 2022; 12:jpm12060891. [PMID: 35743675 PMCID: PMC9224567 DOI: 10.3390/jpm12060891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/25/2022] [Accepted: 05/25/2022] [Indexed: 11/17/2022] Open
Abstract
The presented work addresses the influence of illumination intensity on the amount and locations of singlet oxygen generation in tumor tissue. We used time-resolved optical detection at the typical emission wavelength around 1270 nm and at 1200 nm where there is no singlet oxygen phosphorescence to determine the phosphorescence kinetics. The discussed data comprise in vivo measurements in tumor-laden HET-CAM and mice. The results show that illumination that is too intense is a major issue, affecting many PDT treatments and all singlet oxygen measurements in vivo so far. In such cases, photosensitization and oxygen consumption exceed oxygen supply, limiting singlet oxygen generation to the blood vessels and walls, while photosensitizers in the surrounding tissue will likely not participate. Being a limitation for the treatment, on one hand, on the other, this finding offers a new method for tumor diagnosis when using photosensitizers exploiting the EPR effect. In contrast to high-intensity PDT, some papers reported successful treatment with nanoparticular drugs using much lower illumination intensity. The question of whether, with such illumination, singlet oxygen is indeed generated in areas apart from vessels and walls, is addressed by numerical analysis. In addition, we discuss how to perform measurements at such low intensities.
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4
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Moise N, Friedman A. A mathematical model of immunomodulatory treatment in myocardial infarction. J Theor Biol 2022; 544:111122. [DOI: 10.1016/j.jtbi.2022.111122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 03/16/2022] [Accepted: 04/01/2022] [Indexed: 10/18/2022]
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5
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Aubert V, Kaminski J, Guillaud F, Hauet T, Hannaert P. A Computer Model of Oxygen Dynamics in the Cortex of the Rat Kidney at the Cell-Tissue Level. Int J Mol Sci 2019; 20:E6246. [PMID: 31835730 PMCID: PMC6941061 DOI: 10.3390/ijms20246246] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 12/02/2019] [Accepted: 12/05/2019] [Indexed: 02/06/2023] Open
Abstract
The renal cortex drives renal function. Hypoxia/reoxygenation are primary factors in ischemia-reperfusion (IR) injuries, but renal oxygenation per se is complex and awaits full elucidation. Few mathematical models address this issue: none captures cortical tissue heterogeneity. Using agent-based modeling, we develop the first model of cortical oxygenation at the cell-tissue level (RCM), based on first principles and careful bibliographical analysis. Entirely parameterized with Rat data, RCM is a morphometrically equivalent 2D-slice of cortical tissue, featuring peritubular capillaries (PTC), tubules and interstitium. It implements hemoglobin/O2 binding-release, oxygen diffusion, and consumption, as well as capillary and tubular flows. Inputs are renal blood flow RBF and PO2 feeds; output is average tissue PO2 (tPO2). After verification and sensitivity analysis, RCM was validated at steady-state (tPO2 37.7 ± 2.2 vs. 36.9 ± 6 mmHg) and under transients (ischemic oxygen half-time: 4.5 ± 2.5 vs. 2.3 ± 0.5 s in situ). Simulations confirm that PO2 is largely independent of RBF, except at low values. They suggest that, at least in the proximal tubule, the luminal flow dominantly contributes to oxygen delivery, while the contribution of capillaries increases under partial ischemia. Before addressing IR-induced injuries, upcoming developments include ATP production, adaptation to minutes-hours scale, and segmental and regional specification.
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Affiliation(s)
| | | | | | | | - Patrick Hannaert
- INSERM U1082-IRTOMIT, 86000 Poitiers, France; (V.A.); (J.K.); (F.G.); (T.H.)
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6
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Jayathilake C, Maini PK, Hopf HW, Sean McElwain DL, Byrne HM, Flegg MB, Flegg JA. A mathematical model of the use of supplemental oxygen to combat surgical site infection. J Theor Biol 2019; 466:11-23. [PMID: 30659823 DOI: 10.1016/j.jtbi.2019.01.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 12/13/2018] [Accepted: 01/11/2019] [Indexed: 11/26/2022]
Abstract
Infections are a common complication of any surgery, often requiring a recovery period in hospital. Supplemental oxygen therapy administered during and immediately after surgery is thought to enhance the immune response to bacterial contamination. However, aerobic bacteria thrive in oxygen-rich environments, and so it is unclear whether oxygen has a net positive effect on recovery. Here, we develop a mathematical model of post-surgery infection to investigate the efficacy of supplemental oxygen therapy on surgical-site infections. A 4-species, coupled, set of non-linear partial differential equations that describes the space-time dependence of neutrophils, bacteria, chemoattractant and oxygen is developed and analysed to determine its underlying properties. Through numerical solutions, we quantify the efficacy of different supplemental oxygen regimes on the treatment of surgical site infections in wounds of different initial bacterial load. A sensitivity analysis is performed to investigate the robustness of the predictions to changes in the model parameters. The numerical results are in good agreement with analyses of the associated well-mixed model. Our model findings provide insight into how the nature of the contaminant and its initial density influence bacterial infection dynamics in the surgical wound.
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Affiliation(s)
| | - Philip K Maini
- Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, United Kingdom.
| | | | - D L Sean McElwain
- School of Mathematical Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia.
| | - Helen M Byrne
- Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, United Kingdom.
| | - Mark B Flegg
- School of Mathematical Sciences, Monash University, Australia.
| | - Jennifer A Flegg
- School of Mathematics and Statistics, University of Melbourne, Australia.
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7
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Hackbarth S, Islam W, Fang J, Šubr V, Röder B, Etrych T, Maeda H. Singlet oxygen phosphorescence detection in vivo identifies PDT-induced anoxia in solid tumors. Photochem Photobiol Sci 2019; 18:1304-1314. [DOI: 10.1039/c8pp00570b] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Extracorporeal measurements through the skin achieve sufficient SNR to analyze 1O2 kinetics and evaluate PDT efficiency.
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Affiliation(s)
- Steffen Hackbarth
- Photobiophysics
- Institute of Physics
- Humboldt University of Berlin
- 12489 Berlin
- Germany
| | - Waliul Islam
- Department of Microbiology
- Graduate School of Medical Sciences
- Kumamoto University
- Kumamoto 860-8556
- Japan
| | - Jun Fang
- Laboratory of Microbiology and Oncology
- Faculty of Pharmaceutical Sciences
- Sojo University
- Kumamoto 860-0082
- Japan
| | - Vladimír Šubr
- Institute of Macromolecular Chemistry
- Czech Academy of Sciences
- 16206 Prague
- Czech Republic
| | - Beate Röder
- Photobiophysics
- Institute of Physics
- Humboldt University of Berlin
- 12489 Berlin
- Germany
| | - Tomáš Etrych
- Institute of Macromolecular Chemistry
- Czech Academy of Sciences
- 16206 Prague
- Czech Republic
| | - Hiroshi Maeda
- BioDynamics Research Foundation
- Kumamoto 862-0954
- Japan
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8
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Morshed A, Dutta P. Mathematical Model for Tissue-Level Hypoxic Response in Microfluidic Environment. J Biomech Eng 2018; 140:2654664. [PMID: 28916839 DOI: 10.1115/1.4037915] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Indexed: 12/27/2022]
Abstract
Availability of essential species like oxygen is critical in shaping the dynamics of tumor growth. When the intracellular oxygen level falls below normal, it initiates major cascades in cellular dynamics leading to tumor cell survival. In a cellular block with cells growing away from the blood vessel, the scenario can be aggravated for the cells further inside the block. In this study, the dynamics of intracellular species inside a colony of tumor cells are investigated by varying the cell-block thickness and cell types in a microfluidic cell culture device. The oxygen transport across the cell block is modeled through diffusion, while ascorbate (AS) transport from the extracellular medium is addressed by a concentration-dependent uptake model. The extracellular and intracellular descriptions were coupled through the consumption and traffic of species from the microchannel to the cell block. Our model shows that the onset of hypoxia is possible in HeLa cell within minutes depending on the cell location, although the nutrient supply inside the channel is maintained in normoxic levels. This eventually leads to total oxygen deprivation inside the cell block in the extreme case, representing the development of a necrotic core that maintains a dynamic balance with growing cells and scarce supply. The numerical model reveals that species concentration and hypoxic response are different for HeLa and HelaS3 cells. Results also indicate that the long-term hypoxic response from a microfluidic cellular block stays within 5% of the values of a tissue with the basal layer. The hybrid model can be very useful in designing microfluidic experiments to satisfactorily predict the tissue-level response in cancer research.
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Affiliation(s)
- Adnan Morshed
- School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920 e-mail:
| | - Prashanta Dutta
- Fellow ASME School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920 e-mail:
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9
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Raghavan S, Mehta P, Horst EN, Ward MR, Rowley KR, Mehta G. Comparative analysis of tumor spheroid generation techniques for differential in vitro drug toxicity. Oncotarget 2017; 7:16948-61. [PMID: 26918944 PMCID: PMC4941362 DOI: 10.18632/oncotarget.7659] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 02/11/2016] [Indexed: 11/25/2022] Open
Abstract
Multicellular tumor spheroids are powerful in vitro models to perform preclinical chemosensitivity assays. We compare different methodologies to generate tumor spheroids in terms of resultant spheroid morphology, cellular arrangement and chemosensitivity. We used two cancer cell lines (MCF7 and OVCAR8) to generate spheroids using i) hanging drop array plates; ii) liquid overlay on ultra-low attachment plates; iii) liquid overlay on ultra-low attachment plates with rotating mixing (nutator plates). Analysis of spheroid morphometry indicated that cellular compaction was increased in spheroids generated on nutator and hanging drop array plates. Collagen staining also indicated higher compaction and remodeling in tumor spheroids on nutator and hanging drop arrays compared to conventional liquid overlay. Consequently, spheroids generated on nutator or hanging drop plates had increased chemoresistance to cisplatin treatment (20-60% viability) compared to spheroids on ultra low attachment plates (10-20% viability). Lastly, we used a mathematical model to demonstrate minimal changes in oxygen and cisplatin diffusion within experimentally generated spheroids. Our results demonstrate that in vitro methods of tumor spheroid generation result in varied cellular arrangement and chemosensitivity.
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Affiliation(s)
- Shreya Raghavan
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, USA
| | - Pooja Mehta
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, USA
| | - Eric N Horst
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, USA
| | - Maria R Ward
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, USA
| | - Katelyn R Rowley
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, USA
| | - Geeta Mehta
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, USA.,Department of Biomedical Engineering, University of Michigan, Ann Arbor, USA.,Macromolecular Science and Engineering, University of Michigan, Ann Arbor, USA
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10
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Warren DR, Partridge M. The role of necrosis, acute hypoxia and chronic hypoxia in 18F-FMISO PET image contrast: a computational modelling study. Phys Med Biol 2016; 61:8596-8624. [PMID: 27880734 PMCID: PMC5717515 DOI: 10.1088/1361-6560/61/24/8596] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 09/14/2016] [Accepted: 10/26/2016] [Indexed: 12/22/2022]
Abstract
Positron emission tomography (PET) using 18F-fluoromisonidazole (FMISO) is a promising technique for imaging tumour hypoxia, and a potential target for radiotherapy dose-painting. However, the relationship between FMISO uptake and oxygen partial pressure ([Formula: see text]) is yet to be quantified fully. Tissue oxygenation varies over distances much smaller than clinical PET resolution (<100 μm versus ∼4 mm), and cyclic variations in tumour perfusion have been observed on timescales shorter than typical FMISO PET studies (∼20 min versus a few hours). Furthermore, tracer uptake may be decreased in voxels containing some degree of necrosis. This work develops a computational model of FMISO uptake in millimetre-scale tumour regions. Coupled partial differential equations govern the evolution of oxygen and FMISO distributions, and a dynamic vascular source map represents temporal variations in perfusion. Local FMISO binding capacity is modulated by the necrotic fraction. Outputs include spatiotemporal maps of [Formula: see text] and tracer accumulation, enabling calculation of tissue-to-blood ratios (TBRs) and time-activity curves (TACs) as a function of mean tissue oxygenation. The model is characterised using experimental data, finding half-maximal FMISO binding at local [Formula: see text] of 1.4 mmHg (95% CI: 0.3-2.6 mmHg) and half-maximal necrosis at 1.2 mmHg (0.1-4.9 mmHg). Simulations predict a non-linear non-monotonic relationship between FMISO activity (4 hr post-injection) and mean tissue [Formula: see text] : tracer uptake rises sharply from negligible levels in avascular tissue, peaking at ∼5 mmHg and declining towards blood activity in well-oxygenated conditions. Greater temporal variation in perfusion increases peak TBRs (range 2.20-5.27) as a result of smaller predicted necrotic fraction, rather than fundamental differences in FMISO accumulation under acute hypoxia. Identical late FMISO uptake can occur in regions with differing [Formula: see text] and necrotic fraction, but simulated TACs indicate that additional early-phase information may allow discrimination of hypoxic and necrotic signals. We conclude that a robust approach to FMISO interpretation (and dose-painting prescription) is likely to be based on dynamic PET analysis.
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Affiliation(s)
- Daniel R Warren
- CRUK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Mike Partridge
- CRUK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
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11
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Gillooly JF, Gomez JP, Mavrodiev EV, Rong Y, McLamore ES. Body mass scaling of passive oxygen diffusion in endotherms and ectotherms. Proc Natl Acad Sci U S A 2016; 113:5340-5. [PMID: 27118837 PMCID: PMC4868413 DOI: 10.1073/pnas.1519617113] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The area and thickness of respiratory surfaces, and the constraints they impose on passive oxygen diffusion, have been linked to differences in oxygen consumption rates and/or aerobic activity levels in vertebrates. However, it remains unclear how respiratory surfaces and associated diffusion rates vary with body mass across vertebrates, particularly in relation to the body mass scaling of oxygen consumption rates. Here we address these issues by first quantifying the body mass dependence of respiratory surface area and respiratory barrier thickness for a diversity of endotherms (birds and mammals) and ectotherms (fishes, amphibians, and reptiles). Based on these findings, we then use Fick's law to predict the body mass scaling of oxygen diffusion for each group. Finally, we compare the predicted body mass dependence of oxygen diffusion to that of oxygen consumption in endotherms and ectotherms. We find that the slopes and intercepts of the relationships describing the body mass dependence of passive oxygen diffusion in these two groups are statistically indistinguishable from those describing the body mass dependence of oxygen consumption. Thus, the area and thickness of respiratory surfaces combine to match oxygen diffusion capacity to oxygen consumption rates in both air- and water-breathing vertebrates. In particular, the substantially lower oxygen consumption rates of ectotherms of a given body mass relative to those of endotherms correspond to differences in oxygen diffusion capacity. These results provide insights into the long-standing effort to understand the structural attributes of organisms that underlie the body mass scaling of oxygen consumption.
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Affiliation(s)
- James F Gillooly
- Department of Biology, University of Florida, Gainesville, FL 32611;
| | - Juan Pablo Gomez
- Department of Biology, University of Florida, Gainesville, FL 32611; Florida Museum of Natural History, University of Florida, Gainesville, FL 32611
| | - Evgeny V Mavrodiev
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611
| | - Yue Rong
- Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611
| | - Eric S McLamore
- Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611
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12
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Leung BM, Lesher-Perez SC, Matsuoka T, Moraes C, Takayama S. Media additives to promote spheroid circularity and compactness in hanging drop platform. Biomater Sci 2015. [DOI: 10.1039/c4bm00319e] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Three-dimensional spheroid cultures have become increasingly popular as drug screening platforms, especially with the advent of different high throughput spheroid forming technologies.
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Affiliation(s)
- Brendan M. Leung
- Department of Biomedical Engineering
- Biointerfaces Institute
- University of Michigan
- Ann Arbor
- USA
| | - Sasha Cai Lesher-Perez
- Department of Biomedical Engineering
- Biointerfaces Institute
- University of Michigan
- Ann Arbor
- USA
| | - Toshiki Matsuoka
- Department of Biomedical Engineering
- Biointerfaces Institute
- University of Michigan
- Ann Arbor
- USA
| | - Christopher Moraes
- Department of Biomedical Engineering
- Biointerfaces Institute
- University of Michigan
- Ann Arbor
- USA
| | - Shuichi Takayama
- Department of Biomedical Engineering
- Biointerfaces Institute
- University of Michigan
- Ann Arbor
- USA
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