Publications by authors named "Kristel Klaus"

Background: Existing clinical trials of cognitive behavioural therapies with a trauma focus (CBTs-TF) are underpowered to examine key variables that might moderate treatment effects. We aimed to determine the efficacy of CBTs-TF for young people, relative to passive and active control conditions, and elucidate putative individual-level and treatment-level moderators.

Methods: This was an individual participant data meta-analysis of published and unpublished randomised studies in young people aged 6-18 years exposed to trauma.

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Introduction: Trauma-focused cognitive behavioural therapies are the first-line treatment for posttraumatic stress disorder (PTSD) in children and adolescents. Nevertheless, open questions remain with respect to efficacy: why does this first-line treatment not work for everyone? For whom does it work best? Individual clinical trials often do not provide sufficient statistical power to examine and substantiate moderating factors. To overcome the issue of limited power, an individual participant data meta-analysis of randomised trials evaluating forms of trauma-focused cognitive behavioural therapy in children and adolescents aged 6-18 years will be conducted.

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We investigated morning cortisol, stress, rs1006737 and childhood trauma relationship with methylation. Morning cortisol release, childhood trauma and perceived stress were collected and genotyping for rs1006737 conducted in 103 adult males. Genomic DNA extracted from saliva was bisulphite converted and using pyrosequencing methylation determined at 11 CpG sites within intron 3 of .

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At the molecular level, the neurotransmitter dopamine (DA) is a key regulatory component of executive function in the prefrontal cortex (PFC) and dysfunction in dopaminergic (DAergic) circuitry has been shown to result in impaired working memory (WM). Research has identified multiple common genetic variants suggested to impact on the DA system functionally and also behaviourally to alter WM task performance. In addition, environmental stressors impact on DAergic tone, and this may be one mechanism by which stressors confer vulnerability to the development of neuropsychiatric conditions.

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Research in healthy adults suggests that C957T polymorphism of the dopamine D2 receptor encoding DRD2 and the Taq1A polymorphism of the neighbouring gene ankyrin repeat and kinase domain containing 1 (ANKK1) alter dopaminergic signalling and may influence prefrontally-mediated executive functions. A systematic review and meta-analysis was carried out on the evidence for the association of DRD2 C957T and ANKK1 Taq1A polymorphisms in performance on tasks relating to the three core domains of executive function: working memory, response inhibition and cognitive flexibility in healthy adults. CINAHL, MEDLINE, PsycARTICLES and PsychINFO databases were searched for predefined key search terms associated with the two polymorphisms and executive function.

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Emotional memory may be modulated by BDNF Val66Met and 5-HTTLPR polymorphisms. However, the influence of these genetic variants on the overnight retention of emotional memories has not been investigated in humans. Thirty-six healthy female students were selected to participate in this study based on 5-HTTLPR genotype status (L'/L', L'/S', S'/S').

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Experiencing early life stress (ELS) and subsequent dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis may play a role in the aetiology of mental health disorders. However, the exact mechanisms linking HPA-axis dysregulation with the development of psychopathology have not been fully delineated. Progress in this area is hampered by the complex and often conflicting associations found between markers of HPA-axis function and risk factors for mental health disorders such as impaired executive function (EF) and ELS.

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Introduction: Previous research has indicated that variation in genes encoding catechol-O-methyltransferase () and dopamine receptor D2 () may influence cognitive function and that this may confer vulnerability to the development of mental health disorders such as schizophrenia. However, increasing evidence suggests environmental factors such as early life stress may interact with genetic variants in affecting these cognitive outcomes. This study investigated the effect of and polymorphisms on executive function and the impact of early life stress in healthy adults.

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Background: Current behaviour-based pain assessments for laboratory rodents have significant limitations. Assessment of facial expression changes, as a novel means of pain scoring, may overcome some of these limitations. The Mouse Grimace Scale appears to offer a means of assessing post-operative pain in mice that is as effective as manual behavioural-based scoring, without the limitations of such schemes.

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The revision of EU legislation will ban the use of wild-caught animals in scientific procedures. This change is partially predicated on the assumption that captive-rearing produces animals with reduced fearfulness. Previously, we have shown that hand-reared starlings (Sturnus vulgaris) indeed exhibit reduced fear of humans compared to wild-caught conspecifics.

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