Publications by authors named "Harkness K"

Background: Heart failure (HF) significantly impacts healthcare systems due to high rates of hospital bed utilization and readmission rates. Chronic HF often leads to frequent hospitalizations due to recurrent exacerbations and a decline in patient health status. Intravenous (IV) diuretic administration is essential for treating worsening HF.

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  • * The research involved examining the relationship between MDD, childhood maltreatment (CM), and eCB levels in blood plasma from 91 adults with MDD and 62 healthy participants.
  • * Findings indicate that while MDD is associated with higher eCB levels, the relationship between CM and hippocampal volume shows that only lower levels of one eCB (AEA) are linked to reduced hippocampal volume, highlighting the complex role of eCBs in stress and depression.
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Background: A critical challenge in the study and management of major depressive disorder (MDD) is predicting relapse. We examined the temporal correlation/coupling between depression and anxiety (called Depression-Anxiety Coupling Strength, DACS) as a predictor of relapse in patients with MDD.

Methods: We followed 97 patients with remitted MDD for an average of 394 days.

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  • The CARE pilot trial is testing if surgery or medical treatment is better for people with a brain condition called cerebral cavernous malformation.
  • Researchers faced challenges recruiting enough people for the trial, so they used a special method called the QuinteT Recruitment Intervention to improve the process.
  • They found some problems that made it hard to recruit participants, like disagreements among doctors, but also discovered some doctors were willing to offer surgery, which helped get more people involved.
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  • - The study investigates how major depressive disorder (MDD) affects brain structure and cognitive function, particularly looking at how these changes relate to normal brain development and aging in adolescents and adults.
  • - Researchers analyzed brain data from 304 participants with MDD and 236 without, finding that individuals with MDD had lower brain centile scores, indicating atypical brain aging, and those scores were linked to working memory only in the control group.
  • - The findings suggest that MDD is associated with unusual brain development and aging, but severity of depression and childhood maltreatment did not significantly influence brain measurements or treatment responses.
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A common conjecture is that social success relies on "theory of mind"-the everyday skill of imputing mental states to others. We test the hypothesis that individuals with stronger theory of mind skills and motivation garner more positive first impressions because of how they interact with others. Participants included 334 young adults who were paired with a peer for a first-time meeting.

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Attention and executive function (EF) dysregulation are common in a number of disorders including autism and attention-deficit/hyperactivity disorder (ADHD). Better understanding of the relationship between indirect and direct measures of attention and EF and common neurodevelopmental diagnoses may contribute to more efficient and effective diagnostic assessment in childhood. We obtained cognitive (NIH Toolbox, Little Man Task, Matrix Reasoning Task, and Rey Delayed Recall) and symptom (CBCL, and BPMT) assessment data from the Adolescent Brain and Cognitive Development (ABCD) database for three groups, autistic (N = 110), ADHD (N = 878), and control without autism or ADHD diagnoses (N = 9130) and used ridge regression to determine which attention and EF assessments were most strongly associated with autism or ADHD.

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Background: Stimulant medication is the primary pharmacological treatment for attention dysregulation and is commonly prescribed for children with Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism. Neuroimaging studies of these groups commonly use a 24-48-hour washout period to mediate the effects of stimulant medication on functional connectivity (FC) metrics. However, the impact of washout on functional connectivity has received limited study.

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We examine structural brain characteristics across three diagnostic categories: at risk for serious mental illness; first-presenting episode and recurrent major depressive disorder (MDD). We investigate whether the three diagnostic groups display a stepwise pattern of brain changes in the cortico-limbic regions. Integrated clinical and neuroimaging data from three large Canadian studies were pooled (total n = 622 participants, aged 12-66 years).

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Preclinical research implicates stress-induced upregulation of the enzyme, serum- and glucocorticoid-regulated kinase 1 (SGK1), in reduced hippocampal volume. In the current study, we tested the hypothesis that greater SGK1 mRNA expression in humans would be associated with lower hippocampal volume, but only among those with a history of prolonged stress exposure, operationalized as childhood maltreatment (physical, sexual, and/or emotional abuse). Further, we examined whether baseline levels of SGK1 and hippocampal volume, or changes in these markers over the course of antidepressant treatment, would predict treatment outcomes in adults with major depression [MDD].

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Objectives: Swann's self-verification theory proposes that negative feedback seeking (NFS)-the solicitation of negative feedback from others that confirms one's self-views-works in a negative cycle to maintain and exacerbate depression in the face of interpersonal stress. We propose a cognitive-interpersonal integration account of NFS such that this maladaptive behavior prospectively predicts depression only among those with a trait tendency to ruminate on the causes and consequences of depressed mood and stress.

Method: Participants included 91 young adults who were over-sampled for a lifetime history of a unipolar depressive disorder (age 17-33; 69% women; 67% lifetime depressive disorder).

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Identifying clinically relevant predictors of depressive recurrence following treatment for Major Depressive Disorder (MDD) is critical for relapse prevention. Implicit self-depressed associations (SDAs), defined as implicit cognitive associations between elements of depression (e.g.

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Childhood maltreatment (CM) is a strong transdiagnostic risk factor for future psychopathology. This risk is theorized to emerge partly because of glucocorticoid-mediated atrophy in the hippocampus, which leaves this area sensitive to further volume loss even through adulthood in the face of future stress and the emergence of psychopathology. This proof-of-principle study examines which specific dimensions of internalizing psychopathology in the context of a CM history are associated with decreases in hippocampal volume over a 6-month period.

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Individual differences in cortisol output may influence adolescents' adjustment to the COVID-19 pandemic; however, boys and girls may differ in terms of associations between cortisol output and internalizing symptoms in the context of COVID-19-related stress. We examined whether pre-pandemic cortisol output during an acute stressor, assessed approximately three years prior to the pandemic, predicted change in adolescents' internalizing symptoms early during the COVID-19 pandemic. Consistent with previous work on other life stressors, girls' cortisol output was positively associated with anxious and somatic symptoms early in the pandemic.

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Introduction: The top research priority for cavernoma, identified by a James Lind Alliance Priority setting partnership was 'Does treatment (with neurosurgery or stereotactic radiosurgery) or no treatment improve outcome for people diagnosed with a cavernoma?' This pilot randomised controlled trial (RCT) aims to determine the feasibility of answering this question in a main phase RCT.

Methods And Analysis: We will perform a pilot phase, parallel group, pragmatic RCT involving approximately 60 children or adults with mental capacity, resident in the UK or Ireland, with an unresected symptomatic brain cavernoma. Participants will be randomised by web-based randomisation 1:1 to treatment with medical management and with surgery (neurosurgery or stereotactic radiosurgery) versus medical management alone, stratified by prerandomisation preference for type of surgery.

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Background: Though heart failure patients benefit from multidisciplinary care in heart function clinics (HFCs), utilization is suboptimal and inequitable. This study investigated factors influencing referral and patient access to HFCs from multiple stakeholders' perspectives, namely policy-makers (PM), providers at HFCs and patients.

Methods: In this qualitative study, semi-structured interviews with a purposive sample of Ontario stakeholders were conducted between February-June 2020 and July-December 2022 (paused due to pandemic) via Teams.

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The arrangement of nanoscale building blocks into patterns with microscale periodicity is challenging to achieve via self-assembly processes. Here, we report on the phase-transition-driven collective assembly of gold nanoparticles in a thermotropic liquid crystal. A temperature-induced transition from the isotropic to the nematic phase under anchoring-driven planar alignment leads to the assembly of individual nanometer-sized particles into arrays of micrometer-sized agglomerates, whose size and characteristic spacing can be tuned by varying the cooling rate.

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Objective: Attention Deficit Hyperactivity Disorder (ADHD) is characterized by inattention, hyperactivity, and impulsivity; however, other executive function dysregulation is common, including inhibition and working memory. This study aims to identify CT differences based on executive function performance in individuals with and without ADHD.

Methods: Data for this study was acquired from the Adolescent Brain and Cognitive Development (ABCD) database (61 ADHD, and 61 age and sex matched controls).

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Background: Thrombolysis treatment for ischaemic stroke in patients with pre-existing disabilities, including cognitive impairment, remains controversial. Previous studies have suggested functional outcomes post-thrombolysis are worse in patients with cognitive impairment. This study aimed to compare and explore factors contributing to thrombolysis outcomes, including haemorrhagic complications, in cognitively and non-cognitively impaired patients with ischaemic stroke.

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Cognitive impairment is experienced by many individuals with major depressive disorder (MDD) and is significantly related to sustained disability. Recent work has begun to explore the relationship between childhood adversity (CA) and cognitive impairment in MDD, but this work is limited by unreliable measures of CA. Furthermore, no previous research has examined whether CA relates to cognitive remediation response.

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Objective: Childhood maltreatment is a potent enviromarker of risk for poor response to antidepressant medication (ADM). However, childhood maltreatment is a heterogeneous construct that includes distinct exposures that have distinct neurobiological and psychological correlates. The purpose of the current study is to examine the differential associations of emotional, physical, and sexual maltreatment to ADM outcome and to examine the unique role of anhedonia in driving poor response in patients with specific maltreatment histories.

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The COVID-19 pandemic has led to radical disruptions to the routines of individuals and families, but there are few psychometrically assessed measures for indexing behavioural responses associated with a modern pandemic. Given the likelihood of future pandemics, valid tools for assessing pandemic-related behavioral responses relevant to mental health are needed. This need may be especially salient for studies involving families, as they may experience higher levels of stress and maladjustment related to school and business closures.

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Childhood maltreatment increases risk for sexual and physical revictimization in adulthood. The goal of the current study was to examine whether this risk is associated with specific maltreatment types (i.e.

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Background: In treatment studies of major depressive disorder (MDD), exposure to major life events predicts less symptom improvement and greater likelihood of relapse. In contrast, the impact of minor life events has received less attention. We hypothesized that the impact of minor events on symptom improvement and risk of relapse would be heightened in the presence of concurrent chronic stress.

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Background: Neurological COVID-19 disease has been reported widely, but published studies often lack information on neurological outcomes and prognostic risk factors. We aimed to describe the spectrum of neurological disease in hospitalised COVID-19 patients; characterise clinical outcomes; and investigate factors associated with a poor outcome.

Methods: We conducted an individual patient data (IPD) meta-analysis of hospitalised patients with neurological COVID-19 disease, using standard case definitions.

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