Stuart M Grieve

Publications (71) View all

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  Available from: Stuart M Grieve

  Article: Relationship between body mass index and brain volume in healthy adults.

  John Gunstad, Robert H Paul, Ronald A Cohen, David F Tate, Mary Beth Spitznagel, Stuart Grieve, Evian Gordon
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  ABSTRACT: There is a growing evidence that elevated body mass index (BMI) is associated with adverse neurocognitive outcome, though no study has examined whether morphometric differences are found in persons across the adult life span. We compared 201 healthy individuals in normal weight, overweight, and obese groups (aged 17-79). After correcting for demographic differences, obese individuals showed smaller whole brain and total gray matter volume than normal weight and overweight individuals. These findings support an independent relationship between BMI and brain structure and demonstrate that these differences are not limited to older adults.
  The International journal of neuroscience 12/2008; 118(11):1582-93. · 0.86 Impact Factor
• Article: Stoichiometric Relationship between Na(+) Ions Transported and Glucose Consumed in Human Erythrocytes: Bayesian Analysis of (23)Na and (13)C NMR Time Course Data.

  Max Puckeridge, Bogdan E Chapman, Arthur D Conigrave, Stuart M Grieve, Gemma A Figtree, Philip W Kuchel
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  ABSTRACT: We examined the response of Na(+),K(+)-ATPase (NKA) to monensin, a Na(+) ionophore, with and without ouabain, an NKA inhibitor, in suspensions of human erythrocytes (red blood cells). A combination of (13)C and (23)Na NMR methods allowed the recording of intra- and extracellular Na(+), and (13)C-labeled glucose time courses. The net influx of Na(+) and the consumption of glucose were measured with and without NKA inhibited by ouabain. A Bayesian analysis was used to determine probability distributions of the parameter values of a minimalist mathematical model of the kinetics involved, and then used to infer the rates of Na(+) transported and glucose consumed. It was estimated that the numerical relationship between the number of Na(+) ions transported by NKA per molecule of glucose consumed by a red blood cell was close to the ratio 6.0:1.0, agreeing with theoretical prediction.
  Biophysical Journal 04/2013; 104(8):1676-84. · 3.65 Impact Factor
• Article: Visualizing pericardial inflammation as the cause of acute chest pain in a patient with a congenital pericardial cyst: the incremental diagnostic value of cardiac magnetic resonance.

  Jawad Mazhar, Claire Lawley, Anthony J Gill, Stuart M Grieve, Gemma A Figtree
  European Heart Journal 03/2013; · 10.48 Impact Factor
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  Available from: Justine M Gatt

  Article: The integrate model of emotion, thinking and self regulation: an application to the "paradox of aging".

  Leanne M Williams, Justine M Gatt, Ainslie Hatch, Donna M Palmer, Marie Nagy, Christopher Rennie, Nicholas J Cooper, Charlotte Morris, Stuart Grieve, Carol Dobson-Stone, Peter Schofield, C Richard Clark, Evian Gordon, Martijn Arns, Robert H Paul
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  ABSTRACT: This study was undertaken using the INTEGRATE Model of brain organization, which is based on a temporal continuum of emotion, thinking and self regulation. In this model, the key organizing principle of self adaption is the motivation to minimize danger and maximize reward. This principle drives brain organization across a temporal continuum spanning milliseconds to seconds, minutes and hours. The INTEGRATE Model comprises three distinct processes across this continuum. Emotion is defined by automatic action tendencies triggered by signals that are significant due to their relevance to minimizing danger-maximizing reward (such as abrupt, high contrast stimuli). Thinking represents cognitive functions and feelings that rely on brain and body feedback emerging from around 200 ms post-stimulus onwards. Self regulation is the modulation of emotion, thinking and feeling over time, according to more abstract adaptions to minimize danger-maximize reward. Here, we examined the impact of dispositional factors, age and genetic variation, on this temporal continuum. Brain Resource methodology provided a standardized platform for acquiring genetic, brain and behavioral data in the same 1000 healthy subjects. Results showed a "paradox" of declining function in the "thinking" time scale over the lifespan (6 to 80+ years), but a corresponding preservation or even increase in automatic functions of "emotion" and "self regulation". This paradox was paralleled by a greater loss of grey matter in cortical association areas (assessed using MRI) over age, but a relative preservation of subcortical grey matter. Genetic polymorphisms associated with both healthy function and susceptibility to disorder (including the BDNFVal(66)Met, COMTVal(158/108)Met, MAOA and DRD4 tandem repeat and 5HTT-LPR polymorphisms) made specific contributions to emotion, thinking and self regulatory functions, which also varied according to age.
  Journal of Integrative Neuroscience 10/2008; 7(3):367-404. · 0.76 Impact Factor
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  Available from: Justine M Gatt

  Article: Disturbances in selective information processing associated with the BDNF Val66Met polymorphism: evidence from cognition, the P300 and fronto-hippocampal systems.

  Peter R Schofield, Leanne M Williams, Robert H Paul, Justine M Gatt, Kerri Brown, Agnes Luty, Nicholas Cooper, Stuart Grieve, Carol Dobson-Stone, Charlotte Morris, Stacey A Kuan, Evian Gordon
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  ABSTRACT: In this study, we examined whether the Met allele of the BDNF Val66Met polymorphism is associated with selective disruptions to task-relevant information processing. In 475 non-clinical participants for whom BDNF genotype status was determined we used the 'IntegNeuro' computerized battery of neuropsychological tests to assess cognitive performance, an auditory oddball task to elicit the P300 event-related potential (ERP) and, in smaller subsets of these subjects, high resolution structural MRI imaging to quantify fronto-hippocampal grey matter (n=161), and functional magnetic resonance imaging to assess fronto-hippocampal BOLD activation (n=37). Met/Met (MM) homozygotes had higher verbal recall errors, in the absence of differences in attention, executive function, verbal ability or sensori-motor function. Further, MM homozygotes demonstrated a slowed P300 ERP during the oddball task, with corresponding alterations in hippocampal and lateral prefrontal activation, and a localized reduction in hippocampal grey matter. These results are consistent with a subtle impact of the Met allele on fronto-hippocampal systems involved in selective information processing of stimulus context and memory updating within the normal population. The findings also indicate that heritable endophenotypes such as the P300 have value in elucidating genotype-phenotype relationships.
  Biological psychology 10/2008; 80(2):176-88. · 4.36 Impact Factor