Publications by authors named "Claire L Gibson"

Background: Cannabis use suppresses the endocannabinoid system in healthy individuals. However, the association between cannabis use with the endocannabinoid system is understudied in individuals with psychosis despite the high rate of cannabis use in these individuals.

Methods: We enrolled 83 individuals who were admitted to an inpatient psychiatric unit with psychotic presentations, and measured their plasma levels of main endocannabinoids, Anandamide (AEA) and 2-Acylglycerol (2-AG), and endocannabinoid related compounds, Palmitoylethanolamine, and N-oleoylethanolamine.

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Cerebral ischemic stroke is a leading cause of death and disability, but current pharmacological therapies are limited in their utility and effectiveness. and models of ischemic stroke have been developed which allow us to further elucidate the pathophysiological mechanisms of injury and investigate potential drug targets. models permit mechanistic investigation of the biochemical and molecular mechanisms of injury but are reductionist and do not mimic the complexity of clinical stroke.

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The successful treatment of depressive disorders critically depends on adherence to prescribed treatment regimens. Despite increasing rates of antidepressant medication prescription, adherence to the full treatment course remains poor. Rates of antidepressant non-adherence are higher for uninsured patients and members of some marginalized racial and ethnic communities due to factors such as inequities in healthcare and access to insurance.

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Inflammatory abnormalities are well-documented in individuals with chronic psychotic disorders. Particular attention has focused on interleukin-6 (IL-6) and its correlation with psychotic symptom severity. Cannabis use is associated with an increased risk of psychosis and also has immunomodulating properties.

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Hypertension is an important risk factor for age-related cognitive decline and neuronal pathologies. Studies have shown a correlation between hypertension, disruption in neurovascular coupling and cerebral autoregulation, and cognitive decline. However, the mechanisms behind this are unclear.

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: Following ischemic stroke, recanalisation and restoration of blood flow to the affected area of the brain is critical and directly correlates with patient recovery.  models of ischemic stroke show high variability in outcomes, which may be due to variability in reperfusion.  We previously reported that a surgical refinement in the middle cerebral artery occlusion (MCAO) model of stroke, via repair of the common carotid artery (CCA), removes the reliance on the Circle of Willis for reperfusion and reduced infarct variability.

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As the population ages, the incidence of age-related neurological diseases and cognitive decline increases. To further understand disease-related changes in brain function it is advantageous to examine brain activity changes in healthy aging rodent models to permit mechanistic investigation. Here, we examine the suitability, in rodents, of using a novel, minimally invasive anaesthesia protocol in combination with a functional MRI protocol to assess alterations in neuronal activity due to physiological aging.

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Overdose of stimulant drugs has been associated with increased risk of adverse cardiovascular events (ACVE), some of which may be ascribed to endothelial dysfunction. The aims of this study were to evaluate biomarkers of endothelial dysfunction in emergency department (ED) patients with acute cocaine overdose and to assess the association between in-hospital ACVE in ED patients with any acute drug overdose. This was a prospective consecutive cohort study over 9 months (2015-2016) at two urban, tertiary-care hospital EDs.

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Background: Cerebral ischemic stroke is a significant cause of morbidity and mortality. Sex differences exist following stroke in terms of incidence, symptoms, outcomes and response to some treatments. Importantly, molecular mechanisms of injury, activated following ischemia may differ between the sexes and if so may account, at least in part, for sex differences seen in treatment response.

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Disability and effectiveness of physical therapy are highly variable following ischemic stroke due to different brain regions being affected. Functional magnetic resonance imaging (fMRI) studies of patients in the months and years following stroke have given some insight into how the brain recovers lost functions. Initially, new pathways are recruited to compensate for the lost region, showing as a brighter blood oxygen-level-dependent (BOLD) signal over a larger area during a task than in healthy controls.

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The ischemic stroke is a major cause of adult long-term disability and death worldwide. The current treatments available are limited, with only tissue plasminogen activator (tPA) as an approved drug treatment to target ischemic strokes. Current research in the field of ischemic stroke focuses on better understanding the pathophysiology of stroke, to develop and investigate novel pharmaceutical targets.

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Experimental stroke in rodents, via middle cerebral artery occlusion (MCAO), can be associated with a negative impact on wellbeing and mortality. In hypertensive rodents, pre-stroke craniotomy increased survival and decreased body weight loss post-MCAO. Here we determined the effect, in normotensive Sprague-Dawley rats following 60 minutes MCAO, with or without pre-surgical craniotomy, on post-stroke outcomes in terms of weight loss, neurological deficit, lesion volume and functional outcomes.

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Most in vivo models of ischaemic stroke target the middle cerebral artery and a spectrum of stroke severities, from mild to substantial, can be achieved. This review describes opportunities to improve the in vivo modelling of ischaemic stroke and animal welfare. It provides a number of recommendations to minimise the level of severity in the most common rodent models of middle cerebral artery occlusion, while sustaining or improving the scientific outcomes.

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Animal models are essential for understanding the pathology of stroke and investigating potential treatments. However, stroke models are associated, particularly in mice, with high variability in lesion volume. We investigated whether a surgical refinement where reperfusion is not reliant on the Circle of Willis reduced outcome variability.

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Two multi-centre phase III clinical trials examining the protective potential of progesterone following traumatic brain injury have recently failed to demonstrate any improvement in outcome. Thus, it is timely to consider how this impacts on the translational potential of progesterone treatment for ischaemic stroke. A wealth of experimental evidence supports the neuroprotective properties of progesterone, and associated metabolites, following various types of central nervous system injury.

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Cerebral ischemic stroke is a leading cause of mortality and functional disability. However, unfortunately few effective treatments exist to counteract the deleterious pathological mechanisms triggered following an ischemic event. Epidemiological and experimental studies have revealed a significant difference in the vulnerability of males versus females to both the incidence of stroke and amount of resulting pathology following an ischemic stroke which is also dependent on the stage of lifespan.

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Background: Stroke continues to be a leading cause of mortality and morbidity worldwide, and novel therapeutic options for ischaemic stroke are urgently needed. In this context, drug combination therapies seem to be a viable approach, which has not been fully explored in preclinical studies.

Objectives: In this work, we assessed the dose-response relationship and therapeutic time window, in global brain ischaemia, of a combined therapeutic approach of recombinant human epidermal growth factor (EGF) and growth hormone-releasing peptide-6 (GHRP-6).

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Background: Progesterone is neuroprotective in numerous preclinical CNS injury models including cerebral ischaemia. The aim of this study was two-fold; firstly, we aimed to determine whether progesterone delivery via osmotic mini-pump would confer neuroprotective effects and whether such neuroprotection could be produced in co-morbid animals.

Results: Animals underwent transient middle cerebral artery occlusion.

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Excitotoxicity is a major contributor to cell death during the acute phase of ischemic stroke but aggressive pharmacological targeting of excitotoxicity has failed clinically. Here we investigated whether pretreatment with low doses of memantine, within the range currently used and well tolerated for the treatment of Alzheimer's disease, produce a protective effect in stroke. A coculture preparation exposed to modeled ischemia showed cell death associated with rapid glutamate rises and cytotoxic Ca(2+) influx.

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Ischaemic strokes evoke blood-brain barrier (BBB) disruption and oedema formation through a series of mechanisms involving Rho-kinase activation. Using an animal model of human focal cerebral ischaemia, this study assessed and confirmed the therapeutic potential of Rho-kinase inhibition during the acute phase of stroke by displaying significantly improved functional outcome and reduced cerebral lesion and oedema volumes in fasudil- versus vehicle-treated animals. Analyses of ipsilateral and contralateral brain samples obtained from mice treated with vehicle or fasudil at the onset of reperfusion plus 4 h post-ischaemia or 4 h post-ischaemia alone revealed these benefits to be independent of changes in the activity and expressions of oxidative stress- and tight junction-related parameters.

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The present study assessed the spatial abilities of male and female human participants using different versions of the non-navigational Corsi block-tapping test (CBT) and a search task. Males performed significantly better than females on the standard manual version of the CBT; however, the standard CBT does not allow discrimination between spatial memory span and the role of spatial organisational factors (structure, path length and presence of crossings) in the sequences to recall. These organisational factors were assessed, therefore, in an experiment in which 7-block-sequences had to be recalled in a computerised version of the CBT.

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Preclinical studies suggest progesterone is neuroprotective after cerebral ischemia. The gold standard for assessing intervention effects across studies within and between subgroups is to use meta-analysis based on individual animal data (IAD). Preclinical studies of progesterone in experimental stroke were identified from searches of electronic databases and reference lists.

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