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Quantitative Estimation of Tissue Blood Flow Rate [chapter]

Gillian M. Tozer, Vivien E. Prise, Vincent J. Cunningham
2016 Msphere  
The rate of blood flow through a tissue (F) is a critical parameter for assessing the functional efficiency of a blood vessel network following angiogenesis. This chapter aims to provide the principles behind the estimation of F, how F relates to other commonly used measures of tissue perfusion and a practical approach for estimating F in laboratory animals, using small readily diffusible and metabolically inert radio-tracers. The methods described require relatively nonspecialized equipment.
more » ... wever, the analytical descriptions apply equally to complementary techniques involving more sophisticated non-invasive imaging. Two techniques are described for the quantitative estimation of F based on measuring the rate of tissue uptake following intravenous administration of radioactive iodo-antipyrine (or other suitable tracer). The Tissue Equilibration Technique is the classical approach and the Indicator Fractionation Technique, which is simpler to perform, is a practical alternative in many cases. The experimental procedures and analytical methods for both techniques are given, as well as guidelines for choosing the most appropriate method.
doi:10.1007/978-1-4939-3628-1_18 pmid:27172960 fatcat:kqxzyqkvafdsvl4oosrakxxocm

Quantitative Estimation of Tissue Blood Flow Rate [chapter]

Gillian M. Tozer, Vivien E. Prise, Vincent J. Cunningham
2008 Msphere  
The rate of blood flow through a tissue (F) is a critical parameter for assessing the functional efficiency of a blood vessel network following angiogenesis. This chapter aims to provide the principles behind the estimation of F, how F relates to other commonly used measures of tissue perfusion and a practical approach for estimating F in laboratory animals, using small readily diffusible and metabolically inert radio-tracers. The methods described require relatively nonspecialized equipment.
more » ... wever, the analytical descriptions apply equally to complementary techniques involving more sophisticated non-invasive imaging. Two techniques are described for the quantitative estimation of F based on measuring the rate of tissue uptake following intravenous administration of radioactive iodo-antipyrine (or other suitable tracer). The Tissue Equilibration Technique is the classical approach and the Indicator Fractionation Technique, which is simpler to perform, is a practical alternative in many cases. The experimental procedures and analytical methods for both techniques are given, as well as guidelines for choosing the most appropriate method.
doi:10.1007/978-1-59745-241-0_16 pmid:19301677 fatcat:dtx4balfjvbzre22qlnik4jsd4

Steps to a neurochemistry of personality

Andrew D. Lawrence, Matthias J. Koepp, Roger N. Gunn, Vincent J. Cunningham, Paul M. Grasby
1999 Behavioral and Brain Sciences  
Lawrence a,b , Matthias J. Koepp a,b , Roger N. Gunn a , Vincent J. Cunningham a , and Paul M.  ...  Philip J.  ... 
doi:10.1017/s0140525x99332040 fatcat:katsxmy4m5fj5hs2kq6lgondoe

Cloning, expression, and characterization ofMycobacterium tuberculosisdihydrofolate reductase

E.Lucile White, Larry J Ross, Amanda Cunningham, Vincent Escuyer
2004 FEMS Microbiology Letters  
The gene for dihydrofolate reductase of Mycobacterium tuberculosis was amplified by polymerase chain reaction (PCR) from M. tuberculosis H37Rv strain genomic DNA. The protein was expressed in inclusion bodies in high yield in Escherichia coli under the control of the T7 promoter. Active enzyme was obtained by refolding from guanidine HCl and after a single chromatography step the sample was s 99% homogeneous with a specific activity of V15.5 Wmol min 31 mg 31 . Mass spectrometry analysis
more » ... ed the expected mass of 17.6 kDa. Gel filtration of the enzyme indicated that it was a monomer. Steady-state kinetic parameters were determined and the effect of pH and KCl on the enzyme examined. Methotrexate and trimethoprim inhibited the enzyme.
doi:10.1016/s0378-1097(04)00038-2 pmid:15019741 fatcat:jdzyci562zb65elxwozfcio7ua

Positron Emission Tomography Compartmental Models

Roger N. Gunn, Steve R. Gunn, Vincent J. Cunningham
2001 Journal of Cerebral Blood Flow and Metabolism  
αi) p+q−1 j=1 (s−βj ) , = m i=1 (s−ν i ) (1−VB )1 T b p+q−1 j=1 (s−βj ) n−1 k=1 (s−µ k )+VB p+q−1 j=1 (s−αj ) n k=1 (s−ν k ) n i=1 (s−νi) (1−V B )1 T b p+q−1 j=1 (s−βj ) m−1 k=1 (s−µ k )+V B p+q−1 j=1  ...  + n i=1 ρ i e νit + m+p+q−1 j=1 j e εj t   .  ... 
doi:10.1097/00004647-200106000-00002 pmid:11488533 fatcat:g3iqkjwqirhexfz4epc2rmkf2y

Decreased Brain GABAA-Benzodiazepine Receptor Binding in Panic Disorder

Andrea L. Malizia, Vincent J. Cunningham, Caroline J. Bell, Peter F. Liddle, Terry Jones, David J. Nutt
1998 Archives of General Psychiatry  
Positron emission tomography (PET) allows the measurement of benzodiazepine-␥aminobutyric acid A (GABA A ) receptor kinetics. We employed flumazenil radiolabeled with carbon 11, a radioligand that labels the benzodiazepine site on the GABA A receptor, and fully quantitative, high-sensitivity PET to test the hypothesis that central benzodiazepine site binding is decreased in medication-free patients with panic disorder. Methods: We compared 7 patients with panic disorder who had been off
more » ... on for at least 6 months and who had never abused alcohol with 8 healthy controls. The resulting parametric voxel-by-voxel maps were analyzed by voxel-based and region of interestbased methods using both parametric and nonparametric statistics.
doi:10.1001/archpsyc.55.8.715 pmid:9707382 fatcat:7sq5fqymqrfytgjcy45paigmmq

The irreversible disposal rate of free fatty acids in the plasma of fed and starved rats

Vincent J. Cunningham
1973 Biochemical Journal  
doi:10.1042/bj1360545 pmid:4780689 pmcid:PMC1165988 fatcat:4iuotlc6djd25nj5mrpompv5zu

Divergent and convergent evolution in metastases suggest treatment strategies based on specific metastatic sites

J. J. Cunningham, J. S. Brown, T. L. Vincent, R. A. Gatenby
2015 Evolution, Medicine and Public Health  
a j v; u j À Á nx j !  ...  The divergence of the secondary tumor cells from a strategy of u = 1.2-3.21 means | Cunningham et al. Evolution, Medicine, and Public Health | Cunningham et al.  ... 
doi:10.1093/emph/eov006 pmid:25794501 pmcid:PMC4404930 fatcat:fkikkrfq4jcxnnn4w46i52dvve

Disrupted cortico-limbic connectivity during reward processing in remitted bipolar I disorder

Sunny J Dutra, Vincent Man, Hedy Kober, William A Cunningham, June Gruber
2017 Bipolar Disorders  
Objectives: Bipolar disorder (BD) is associated with elevated reward sensitivity and persistent positive affect, yet the neural mechanisms underlying these patterns are not well understood. In the present study, we examined putative disruptions in communication within a well-known cortico-limbic reward circuit during reward processing as a potential contributing mechanism to these symptoms. Methods: The present investigation employed a within-and between-subjects design utilizing a monetary and
more » ... social incentive delay task among adults with bipolar disorder type I (BD; N = 24) and a healthy non-psychiatric control group (HC; N = 25) during functional magnetic resonance imaging (fMRI). Participants in the BD group were remitted at the time of testing. Results: Functional connectivity analyses revealed increased connectivity between the ventral striatum (VS) seed region and orbitofrontal cortex (OFC) as well as the amygdala during processing of reward receipt in the BD group. After omission of expected rewards, the BD group showed decreased functional connectivity between the VS and a medial frontopolar cortex (mFPC) region associated with consideration of behavioral alternatives. Follow-up analyses within the BD group showed that increased VS-OFC connectivity after reward receipt, and decreased VS-mFPC connected after reward omission, were associated with higher levels of subthreshold mania symptoms. Conclusions: Results point toward potential mechanisms implicated in elevated reward sensitivity in BD. Enhanced VS-OFC connectivity after reward receipt may be involved in elevated valuation of rewards whereas blunted VS-mFPC connectivity after reward omission may reflect a failure to consider behavioral alternatives to reward pursuit. K E Y W O R D S bipolar disorder, monetary, reward, social, ventral striatum
doi:10.1111/bdi.12560 pmid:29024194 fatcat:7p6t5kxmsbctjnwhvuyehn5qoa

In vitro and in vivo genotoxicity of 1,3-butadiene and metabolites

G T Arce, D R Vincent, M J Cunningham, W N Choy, A M Sarrif
1990 Environmental Health Perspectives  
Cunningham et al.  ...  SCE analysis was performed as described by Cunningham et al. (21) . At least 25 cells per treatment group were scored.  ... 
doi:10.1289/ehp.908675 pmid:2205494 pmcid:PMC1567734 fatcat:ljl6wrubjzarrf734ebgoaqmma

Parametric Imaging of Ligand-Receptor Binding in PET Using a Simplified Reference Region Model

Roger N. Gunn, Adriaan A. Lammertsma, Susan P. Hume, Vincent J. Cunningham
1997 NeuroImage  
B i (t j ) RSS i ϭ ͚ jϭ1 n w.  ...  For each voxel C PET (t j ) measured concentration at time t j . j ϭ 1, . . . , n, where n is the number of frames For i ϭ 1:100 3 1 2 4 ϭ M (2i Ϫ 1:2i, :).W.C PET (t j ) C T (t j ) ϭ 1 C R (t j ) ϩ 2  ... 
doi:10.1006/nimg.1997.0303 pmid:9417971 fatcat:rccltc7htvb7bexojxdnhoi3lm

Parametric image reconstruction using spectral analysis of PET projection data

Steven R Meikle, Julian C Matthews, Vincent J Cunningham, Dale L Bailey, Lefteris Livieratos, Terry Jones, Pat Price
1998 Physics in Medicine and Biology  
Now, the spectral analysis model (1) can be substituted into the time-dependent Radon transform: y i (t) = jJ b ij x j (t) (6) = jJ b ij N k=1 q(t) ⊗ α jk exp(−β k t) (7) where y i (t) is the number  ...  of counts recorded in projection bin i at time t, J is the subset of pixels that contribute to bin i, b ij is the probability of a photon emitted from pixel j being recorded in bin i and x j (t) is the  ... 
doi:10.1088/0031-9155/43/3/016 pmid:9533143 fatcat:ujczlpin7rcxxhtmv2i4mo24a4

Exploring the Antimicrobial Action of Quaternary Amines against Acinetobacter baumannii

Gregory A. Knauf, Ashley L. Cunningham, Misha I. Kazi, Ian M. Riddington, Alexander A. Crofts, Vincent Cattoir, M. Stephen Trent, Bryan W. Davies, John J. Mekalanos
2018 mBio  
Quaternary amine compounds (QAC) are potent antimicrobials used to prevent the spread of pathogenic bacteria. While they are known for their membrane-damaging properties, QAC action has been suggested to extend beyond the surface to intracellular targets. Here we characterize the range of action of the QAC biocide benzalkonium chloride (BZK) against the bacterial pathogen Acinetobacter baumannii. At high concentrations, BZK acts through membrane disruption, but at low concentrations we show
more » ... wide-spread protein aggregation is associated with BZK-induced cell death. Resistance to BZK is found to develop through ribosomal protein mutations that protect A. baumannii against BZK-induced protein aggregation. The multifunctional impact of BZK led us to discover that alternative QAC structures, with low human toxicity, retain potent action against multidrug-resistant A. baumannii, Staphylococcus aureus, and Clostridium difficile and present opportunities for their development as antibiotics. IMPORTANCE Quaternary amine compounds (QACs) are widely used to prevent the spread of bacterial pathogens, but our understanding of their mode of action is incomplete. Here we describe disruption of bacterial proteostasis as an unrecognized action of QAC antimicrobial action and uncover the potential of diverse QAC structures to act as multitarget antibiotics.
doi:10.1128/mbio.02394-17 pmid:29437928 pmcid:PMC5801471 fatcat:h6ff5o425fg5nhy6ss6jlutmqa

Gray matter blood flow change is unevenly distributed during moderate isocapnic hypoxia in humans

Andrew P. Binks, Vincent J. Cunningham, Lewis Adams, Robert B. Banzett
2008 Journal of applied physiology  
Binks AP, Cunningham VJ, Adams L, Banzett RB. Gray matter blood flow change is unevenly distributed during moderate isocapnic hypoxia in humans.  ...  Binks AP, Cunningham VJ, Adams L, Banzett RB. Gray matter blood flow change is unevenly distributed during moderate isocapnic hypoxia in humans. J Appl Physiol 104: 212-217, 2008.  ...  0.40Ϯ0.07 0.40Ϯ0.03 5 70.6Ϯ4.0 96.6Ϯ0.9 41.9Ϯ2.4 94.0Ϯ1.6 43.9Ϯ0.7 44.2Ϯ1.5 0.62Ϯ0.20 0.46Ϯ0.10 Table 2 . 2 Designated ROI for comparison of normoxic and hypoxic blood O 2 levels J  ... 
doi:10.1152/japplphysiol.00069.2007 pmid:17991793 fatcat:2yj55qeuovftpg7zgbusvexrqm

Acute increases in synaptic GABA detectable in the living human brain: A [11C]Ro15-4513 PET study

Paul R.A. Stokes, Jim F. Myers, Nicola J. Kalk, Ben J. Watson, David Erritzoe, Sue J. Wilson, Vincent J. Cunningham, Daniela Riano Barros, Alexander Hammers, Federico E. Turkheimer, David J. Nutt, Anne R. Lingford-Hughes
2014 NeuroImage  
Spectral analysis (Cunningham and Jones, 1993; Turkheimer et al., 1994 ) is a basis function technique, used to convolve the plasma input function with first order poly-exponentials, to fit regional TAC  ... 
doi:10.1016/j.neuroimage.2014.05.035 pmid:24844747 fatcat:dvmmakvfivbbphzlyj46fwec7e
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