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A call for digital inclusion initiatives in mental health services: An integrative review. J Psychiatr Ment Health Nurs 2023; 30:911-941. [PMID: 37022715 DOI: 10.1111/jpm.12931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 03/12/2023] [Accepted: 03/16/2023] [Indexed: 04/07/2023]
Abstract
WHAT IS KNOWN ON THE SUBJECT?: Digital tools such as video calls or mobile phone applications (apps) are increasingly used in the provision of mental healthcare. There is evidence that people with mental health problems are more likely to face digital exclusion: that is, they do not have access to devices and/or skills to use technology. This leaves some people unable to use digital mental health services (e.g., apps or online appointments) or to benefit more generally from access to the digital world (e.g., online shopping or connecting with others virtually). People can be digitally included through initiatives that provide devices, Internet and digital mentoring to increase knowledge and confidence when using technology. WHAT THE PAPER ADDS TO EXISTING KNOWLEDGE?: Some initiatives in academic studies and grey literature have been shown to increase access to and knowledge of technology, but this has been outside of mental health care settings. There are currently limited digital inclusion initiatives that take into consideration the specific needs of people with mental health problems, and how they can be equipped and familiarised with digital technologies to help their recovery journey and everyday life activities. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Further work is needed to improve the provision of digital tools in mental health care, with more practical digital inclusion initiatives to ensure equal access for all. If digital exclusion is not addressed, the gap between people with and those without digital skills or access to technology will continue to grow, enlarging mental health inequalities. ABSTRACT INTRODUCTION: The rise in the provision of digital healthcare during the pandemic has called attention to digital exclusion: inequality in access and/or capacity to use digital technologies. Digital exclusion is more profound in people with mental health problems, leaving an implementation gap of digital practice in mental health services. AIM Identify the available evidence of (a) addressing digital exclusion in mental health care and (b) the practical solutions to enhance uptake of digital mental health. METHOD Digital inclusion initiatives were searched from both academic and grey literature available and published between the years 2007 and 2021. RESULTS A limited number of academic studies and initiatives were found that supported people with mental health difficulties who had limited skills and/or access to overcome digital exclusion. DISCUSSION Further work is needed to combat digital exclusion and establish ways to reduce the implementation gap in mental health services. IMPLICATIONS FOR PRACTICE Access to devices, Internet connectivity and digital mentoring for mental health service users is essential. More studies and programmes are needed to disseminate impact and results for digital inclusion initiatives for people with mental health problems and to inform best practice for digital inclusion within mental health services.
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The digital divide: factors impacting on uptake of remote therapy in a South London psychological therapy service for people with psychosis. J Ment Health 2022; 31:825-832. [PMID: 34319202 DOI: 10.1080/09638237.2021.1952955] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND Remote therapy promises a cost-effective way of increasing delivery of psychological-therapy in underserved populations. However, research shows a "digital divide", with some groups experiencing digital exclusion. AIMS To assess whether technology, accessibility, and demographic factors influence remote therapy uptake among individuals with psychosis, and whether demographic factors are associated with digital exclusion. METHODS Remote therapy uptake and demographics were assessed in people (n = 51) within a psychology-led service for psychosis, using a survey of access to digital hardware, data and private space. RESULTS The majority of individuals had access to digital devices, but 29% did not meet minimum requirements for remote therapy. Nineteen (37%) individuals declined remote therapy. Those who accepted were significantly younger and more likely to have access to technology than those who declined. The mean age of those with access to smartphones and large screen devices was younger than those without access. CONCLUSIONS A subgroup of people with psychosis face barriers to remote therapy and a significant minority are digitally excluded. Older age is a key factor influencing remote therapy uptake, potentially related to less access to digital devices. Services must minimize exclusion through provision of training, hardware and data, whilst promoting individual choice.
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Intelligence, educational attainment, and brain structure in those at familial high-risk for schizophrenia or bipolar disorder. Hum Brain Mapp 2020; 43:414-430. [PMID: 33027543 PMCID: PMC8675411 DOI: 10.1002/hbm.25206] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 08/28/2020] [Accepted: 09/03/2020] [Indexed: 12/25/2022] Open
Abstract
First-degree relatives of patients diagnosed with schizophrenia (SZ-FDRs) show similar patterns of brain abnormalities and cognitive alterations to patients, albeit with smaller effect sizes. First-degree relatives of patients diagnosed with bipolar disorder (BD-FDRs) show divergent patterns; on average, intracranial volume is larger compared to controls, and findings on cognitive alterations in BD-FDRs are inconsistent. Here, we performed a meta-analysis of global and regional brain measures (cortical and subcortical), current IQ, and educational attainment in 5,795 individuals (1,103 SZ-FDRs, 867 BD-FDRs, 2,190 controls, 942 schizophrenia patients, 693 bipolar patients) from 36 schizophrenia and/or bipolar disorder family cohorts, with standardized methods. Compared to controls, SZ-FDRs showed a pattern of widespread thinner cortex, while BD-FDRs had widespread larger cortical surface area. IQ was lower in SZ-FDRs (d = -0.42, p = 3 × 10-5 ), with weak evidence of IQ reductions among BD-FDRs (d = -0.23, p = .045). Both relative groups had similar educational attainment compared to controls. When adjusting for IQ or educational attainment, the group-effects on brain measures changed, albeit modestly. Changes were in the expected direction, with less pronounced brain abnormalities in SZ-FDRs and more pronounced effects in BD-FDRs. To conclude, SZ-FDRs and BD-FDRs show a differential pattern of structural brain abnormalities. In contrast, both had lower IQ scores and similar school achievements compared to controls. Given that brain differences between SZ-FDRs and BD-FDRs remain after adjusting for IQ or educational attainment, we suggest that differential brain developmental processes underlying predisposition for schizophrenia or bipolar disorder are likely independent of general cognitive impairment.
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Schizophrenia polygenic risk score influence on white matter microstructure. J Psychiatr Res 2020; 121:62-67. [PMID: 31770658 DOI: 10.1016/j.jpsychires.2019.11.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 11/17/2019] [Accepted: 11/18/2019] [Indexed: 12/25/2022]
Abstract
Schizophrenia (SZ) and bipolar disorder (BD) are highly heritable, share symptomatology, and have a polygenic architecture. The impact of recent polygenic risk scores (PRS) for psychosis, which combine multiple genome-wide associated risk variations, should be assessed on heritable brain phenotypes also previously associated with the illnesses, for a better understanding of the pathways to disease. We have recently reported on the current SZ PRS's ability to predict 1st episode of psychosis case-control status and general cognition. Herein, we test its penetrance on white matter microstructure, which is known to be impaired in SZ, in BD and their relatives, using 141 participants (including SZ, BP, relatives of SZ or BP patients, and healthy volunteers), and two white matter integrity indexes: fractional anisotropy (FA) and mean diffusivity (MD). No significant correlation between the SZ PRS and FA or MD was found, thus it remains unclear whether white matter changes are primarily associated with SZ genetic risk profiles.
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The Association Between Familial Risk and Brain Abnormalities Is Disease Specific: An ENIGMA-Relatives Study of Schizophrenia and Bipolar Disorder. Biol Psychiatry 2019; 86:545-556. [PMID: 31443932 PMCID: PMC7068800 DOI: 10.1016/j.biopsych.2019.03.985] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 03/19/2019] [Accepted: 03/24/2019] [Indexed: 11/30/2022]
Abstract
BACKGROUND Schizophrenia and bipolar disorder share genetic liability, and some structural brain abnormalities are common to both conditions. First-degree relatives of patients with schizophrenia (FDRs-SZ) show similar brain abnormalities to patients, albeit with smaller effect sizes. Imaging findings in first-degree relatives of patients with bipolar disorder (FDRs-BD) have been inconsistent in the past, but recent studies report regionally greater volumes compared with control subjects. METHODS We performed a meta-analysis of global and subcortical brain measures of 6008 individuals (1228 FDRs-SZ, 852 FDRs-BD, 2246 control subjects, 1016 patients with schizophrenia, 666 patients with bipolar disorder) from 34 schizophrenia and/or bipolar disorder family cohorts with standardized methods. Analyses were repeated with a correction for intracranial volume (ICV) and for the presence of any psychopathology in the relatives and control subjects. RESULTS FDRs-BD had significantly larger ICV (d = +0.16, q < .05 corrected), whereas FDRs-SZ showed smaller thalamic volumes than control subjects (d = -0.12, q < .05 corrected). ICV explained the enlargements in the brain measures in FDRs-BD. In FDRs-SZ, after correction for ICV, total brain, cortical gray matter, cerebral white matter, cerebellar gray and white matter, and thalamus volumes were significantly smaller; the cortex was thinner (d < -0.09, q < .05 corrected); and third ventricle was larger (d = +0.15, q < .05 corrected). The findings were not explained by psychopathology in the relatives or control subjects. CONCLUSIONS Despite shared genetic liability, FDRs-SZ and FDRs-BD show a differential pattern of structural brain abnormalities, specifically a divergent effect in ICV. This may imply that the neurodevelopmental trajectories leading to brain anomalies in schizophrenia or bipolar disorder are distinct.
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Balancing ACT: evaluating the effectiveness of psychoeducation and Acceptance and Commitment Therapy (ACT) groups for people with bipolar disorder: study protocol for pilot randomised controlled trial. Trials 2018; 19:436. [PMID: 30103785 PMCID: PMC6090792 DOI: 10.1186/s13063-018-2789-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 07/05/2018] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Bipolar disorder is a chronic and disabling psychiatric condition, characterised by recurrent episodes of mania, hypomania and depression. It places a heavy burden on sufferers and families, with high societal and healthcare costs. Many service users with a diagnosis of bipolar disorder also experience prominent psychotic symptoms, with differential diagnoses of schizoaffective disorder, and relapses characterised by repeated manic psychotic episodes and grandiosity. Such presentations require specific adaptations to standard bipolar disorder interventions in order to address their psychosis, alongside mood regulation, with a particular emphasis on impulsivity, irritability, disinhibition and elation. The Balancing ACT study aims to evaluate an innovative group intervention combining Acceptance and Commitment Therapy and psychoeducation approaches (ACT/PE) with individuals experiencing bipolar disorder and/or symptoms within community psychosis services. METHODS The Balancing ACT study is a randomised controlled trial comparing Balancing ACT groups (ACT/PE) plus routine care to routine care alone. Balancing ACT (ACT/PE) comprises ten group sessions, each lasting 2 hours, delivered weekly. The primary outcome is psychological wellbeing; secondary outcomes are mental health relapses (measured by service use averages for the 12 months pre baseline and 3 months post baseline). We will also measure mood, distress, recovery and psychological change processes. Participants will be randomised in a 1:1 ratio, after baseline assessment. Outcomes will be assessed by trained assessors blind to treatment condition at 0, 10 and 14 weeks. Recruitment began in April 2017 and is on-going until the end of October 2017. DISCUSSION The Balancing ACT study will contribute to the currently limited evidence base for psychological interventions for people experiencing bipolar disorder and/or symptoms in the context of community psychosis services. TRIAL REGISTRATION ISRCTN73327972 . Registered on 27 March 2017. Balancing ACT: evaluating the effectiveness of psychoeducation and Acceptance and Commitment Therapy (ACT) groups for people with bipolar disorder.
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Sensitivity assessment of sea lice to chemotherapeutants: Current bioassays and best practices. JOURNAL OF FISH DISEASES 2018; 41:995-1003. [PMID: 29251354 DOI: 10.1111/jfd.12768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/27/2017] [Accepted: 11/15/2017] [Indexed: 06/07/2023]
Abstract
Traditional bioassays are still necessary to test sensitivity of sea lice species to chemotherapeutants, but the methodology applied by the different scientists has varied over time in respect to that proposed in "Sea lice resistance to chemotherapeutants: A handbook in resistance management" (2006). These divergences motivated the organization of a workshop during the Sea Lice 2016 conference "Standardization of traditional bioassay process by sharing best practices." There was an agreement by the attendants to update the handbook. The objective of this article is to provide a baseline analysis of the methodology for traditional bioassays and to identify procedures that need to be addressed to standardize the protocol. The methodology was divided into the following steps: bioassay design; material and equipment; sea lice collection, transportation and laboratory reception; preparation of dilution; parasite exposure; response evaluation; data analysis; and reporting. Information from the presentations of the workshop, and also from other studies, allowed for the identification of procedures inside a given step that need to be standardized as they were reported to be performed differently by the different working groups. Bioassay design and response evaluation were the targeted steps where more procedures need to be analysed and agreed upon.
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Sea Lice 2016. JOURNAL OF FISH DISEASES 2018; 41:859-860. [PMID: 29878407 DOI: 10.1111/jfd.12801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 02/13/2018] [Indexed: 06/08/2023]
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The drivers of sea lice management policies and how best to integrate them into a risk management strategy: An ecosystem approach to sea lice management. JOURNAL OF FISH DISEASES 2018; 41:927-933. [PMID: 29027681 DOI: 10.1111/jfd.12705] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 07/20/2017] [Accepted: 07/23/2017] [Indexed: 06/07/2023]
Abstract
The control of sea lice infestations on cultivated Atlantic salmon is a major issue in many regions of the world. The numerous drivers which shape the priorities and objectives of the control strategies vary for different regions/jurisdictions. These range from the animal welfare and economic priorities of the producers, to the mitigation of any potential impacts on wild stocks. Veterinary ethics, environmental impacts of therapeutants, and impacts for organic certification of the produce are, amongst others, additional sets of factors which should be considered. Current best practice in both EU and international environmental law advocates a holistic ecosystem approach to assessment of impacts and risks. The issues of biosecurity and ethics, including the impacts on the stocks of species used as cleaner fish, are areas for inclusion in such a holistic ecosystem assessment. The Drivers, Pressures, State, Impacts, Responses (DPSIR) process is examined as a decision-making framework and potential applications to sea lice management are outlined. It is argued that this is required to underpin any integrated sea lice management (ISLM) strategy to balance pressures and outcomes and ensure a holistic approach to managing the issue of sea lice infestations on farmed stock on a medium to long-term basis.
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Effects of risk for bipolar disorder on brain function: A twin and family study. Eur Neuropsychopharmacol 2017; 27:494-503. [PMID: 28392151 PMCID: PMC5446324 DOI: 10.1016/j.euroneuro.2017.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 11/29/2016] [Accepted: 03/05/2017] [Indexed: 11/25/2022]
Abstract
Bipolar disorder (BPD) is associated with altered regional brain function during the performance of cognitive tasks. The relative contribution of genetic and environmental risk factors for BPD to these changes has not yet been quantified. We sought to address this issue in a functional neuroimaging study of people who varied in their risk for BPD. Functional magnetic resonance imaging was used to study 124 subjects (29 twin and 9 sibling pairs with at least one member with BPD, and 24 healthy twin pairs) performing a working memory task. We assessed the influence of risk for BPD on regional brain function during the task in a two stage process. Firstly, we identified areas where there were group differences in activation. Secondly, we estimated the heritability and phenotypic correlation of activation and BPD using genetic modeling. BPD was associated with increased activation in the anterior cingulate, orbitofrontal, medial prefrontal, and left precentral cortices, and in the precuneus. Within these regions, activation in the orbitofrontal cortex rendered the most significant heritability estimate (h2=0.40), and was significantly correlated with BPD phenotype (rph=0.29). A moderate proportion of the genetic influences (rg=0.69) acting on both BPD and on the degree of orbitofrontal activation were shared. These findings suggest that genetic factors that confer vulnerability to BPD alter brain function in BPD.
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New insights into the endophenotypic status of cognition in bipolar disorder: genetic modelling study of twins and siblings. Br J Psychiatry 2016; 208:539-47. [PMID: 26989096 DOI: 10.1192/bjp.bp.115.167239] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 09/20/2015] [Indexed: 11/23/2022]
Abstract
BACKGROUND Twin studies have lacked statistical power to apply advanced genetic modelling techniques to the search for cognitive endophenotypes for bipolar disorder. AIMS To quantify the shared genetic variability between bipolar disorder and cognitive measures. METHOD Structural equation modelling was performed on cognitive data collected from 331 twins/siblings of varying genetic relatedness, disease status and concordance for bipolar disorder. RESULTS Using a parsimonious AE model, verbal episodic and spatial working memory showed statistically significant genetic correlations with bipolar disorder (rg = |0.23|-|0.27|), which lost statistical significance after covarying for affective symptoms. Using an ACE model, IQ and visual-spatial learning showed statistically significant genetic correlations with bipolar disorder (rg = |0.51|-|1.00|), which remained significant after covarying for affective symptoms. CONCLUSIONS Verbal episodic and spatial working memory capture a modest fraction of the bipolar diathesis. IQ and visual-spatial learning may tap into genetic substrates of non-affective symptomatology in bipolar disorder.
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Genome-wide discovered psychosis-risk gene ZNF804A impacts on white matter microstructure in health, schizophrenia and bipolar disorder. PeerJ 2016; 4:e1570. [PMID: 26966642 PMCID: PMC4782689 DOI: 10.7717/peerj.1570] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2015] [Accepted: 12/15/2015] [Indexed: 01/10/2023] Open
Abstract
Background. Schizophrenia (SZ) and bipolar disorder (BD) have both been associated with reduced microstructural white matter integrity using, as a proxy, fractional anisotropy (FA) detected using diffusion tensor imaging (DTI). Genetic susceptibility for both illnesses has also been positively correlated in recent genome-wide association studies with allele A (adenine) of single nucleotide polymorphism (SNP) rs1344706 of the ZNF804A gene. However, little is known about how the genomic linkage disequilibrium region tagged by this SNP impacts on the brain to increase risk for psychosis. This study aimed to assess the impact of this risk variant on FA in patients with SZ, in those with BD and in healthy controls. Methods. 230 individuals were genotyped for the rs1344706 SNP and underwent DTI. We used tract-based spatial statistics (TBSS) followed by an analysis of variance, with threshold-free cluster enhancement (TFCE), to assess underlying effects of genotype, diagnosis and their interaction, on FA. Results. As predicted, statistically significant reductions in FA across a widely distributed brain network (p < 0.05, TFCE-corrected) were positively associated both with a diagnosis of SZ or BD and with the double (homozygous) presence of the ZNF804A rs1344706 risk variant (A). The main effect of genotype was medium (d = 0.48 in a 44,054-voxel cluster) and the effect in the SZ group alone was large (d = 1.01 in a 51,260-voxel cluster), with no significant effects in BD or controls, in isolation. No areas under a significant diagnosis by genotype interaction were found. Discussion. We provide the first evidence in a predominantly Caucasian clinical sample, of an association between ZNF804A rs1344706 A-homozygosity and reduced FA, both irrespective of diagnosis and particularly in SZ (in overlapping brain areas). This suggests that the previously observed involvement of this genomic region in psychosis susceptibility, and in impaired functional connectivity, may be conferred through it inducing abnormalities in white matter microstructure.
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Abstract
Individual differences in cognitive ability and social behaviour are influenced by the variability in the structure and function of the limbic system. A strong heritability of the limbic cortex has been previously reported, but little is known about how genetic factors influence specific limbic networks. We used diffusion tensor imaging tractography to investigate heritability of different limbic tracts in 52 monozygotic and 34 dizygotic healthy adult twins. We explored the connections that contribute to the activity of three distinct functional limbic networks, namely the dorsal cingulum (‘medial default-mode network’), the ventral cingulum and the fornix (‘hippocampal-diencephalic-retrosplenial network’) and the uncinate fasciculus (‘temporo-amygdala-orbitofrontal network’). Genetic and environmental variances were mapped for multiple tract-specific measures that reflect different aspects of the underlying anatomy. We report the highest heritability for the uncinate fasciculus, a tract that underpins emotion processing, semantic cognition, and social behaviour. High to moderate genetic and shared environmental effects were found for pathways important for social behaviour and memory, for example, fornix, dorsal and ventral cingulum. These findings indicate that within the limbic system inheritance of specific traits may rely on the anatomy of distinct networks and is higher for fronto-temporal pathways dedicated to complex social behaviour and emotional processing.
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Genetic and Environmental Influences On Brain Function in Schizophrenia. an FMRI Study of the Maudsley Twin and Family Cohorts. Eur Psychiatry 2015. [DOI: 10.1016/s0924-9338(15)31336-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Response to M Krkošek, C W Revie, B Finstad and C D Todd's comment on Jackson et al. 'Impact of Lepeophtheirus salmonis infestations on migrating Atlantic salmon, Salmo salar L., smolts at eight locations in Ireland with an analysis of lice-induced marine mortality'. JOURNAL OF FISH DISEASES 2014; 37:419-421. [PMID: 24611448 PMCID: PMC4314703 DOI: 10.1111/jfd.12239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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Social networks and support in first-episode psychosis: exploring the role of loneliness and anxiety. Soc Psychiatry Psychiatr Epidemiol 2014; 49:359-66. [PMID: 23955376 PMCID: PMC4081600 DOI: 10.1007/s00127-013-0754-3] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 07/31/2013] [Indexed: 12/11/2022]
Abstract
PURPOSE To investigate social support and network features in people with first-episode psychosis, and to examine anxiety as a possible mediator between loneliness and a rating of paranoia. METHOD Thirty-eight people with first-episode psychosis were recruited for a cross-sectional study. Self-report questionnaires and structured interviews assessed symptoms, functioning, and qualitative social network and support features. A mood-induction task involved watching anxiety-inducing pictures on a computer screen. Visual analogue scales assessed changes in paranoia, anxiety and loneliness and a mediation analysis was conducted. RESULTS One-third of the sample (34%) had no confidant [95% CI (18.4, 50.0%)]. The average number of weekly contacts was 3.9, with 2.6 lonely days. Poor perceived social support, loneliness and the absence of a confidant were strongly associated with psychosis and depressive symptoms (0.35 < rs < 0.60). The association between loneliness and paranoia was mediated through anxiety (ab = 0.43, z = 3.5; p < 0.001). CONCLUSIONS Even at first episode, a large proportion of people with psychosis have poor perceived support, no confidant and report several lonely days a week. Patients without a confidant appear to be more susceptible to feeling lonely and anxious. Anxiety may be one pathway through which loneliness affects psychosis. Interventions which focus on this are indicated.
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Interaction between effects of genes coding for dopamine and glutamate transmission on striatal and parahippocampal function. Hum Brain Mapp 2013; 34:2244-58. [PMID: 22438288 PMCID: PMC6869864 DOI: 10.1002/hbm.22061] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2011] [Revised: 01/08/2012] [Accepted: 01/25/2012] [Indexed: 12/17/2022] Open
Abstract
The genes for the dopamine transporter (DAT) and the D-Amino acid oxidase activator (DAOA or G72) have been independently implicated in the risk for schizophrenia and in bipolar disorder and/or their related intermediate phenotypes. DAT and G72 respectively modulate central dopamine and glutamate transmission, the two systems most robustly implicated in these disorders. Contemporary studies have demonstrated that elevated dopamine function is associated with glutamatergic dysfunction in psychotic disorders. Using functional magnetic resonance imaging we examined whether there was an interaction between the effects of genes that influence dopamine and glutamate transmission (DAT and G72) on regional brain activation during verbal fluency, which is known to be abnormal in psychosis, in 80 healthy volunteers. Significant interactions between the effects of G72 and DAT polymorphisms on activation were evident in the striatum, parahippocampal gyrus, and supramarginal/angular gyri bilaterally, the right insula, in the right pre-/postcentral and the left posterior cingulate/retrosplenial gyri (P < 0.05, FDR-corrected across the whole brain). This provides evidence that interactions between the dopamine and the glutamate system, thought to be altered in psychosis, have an impact in executive processing which can be modulated by common genetic variation.
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Impact of Lepeophtheirus salmonis infestations on migrating Atlantic salmon , Salmo salar L., smolts at eight locations in Ireland with an analysis of lice-induced marine mortality. JOURNAL OF FISH DISEASES 2013; 36:273-81. [PMID: 23298412 PMCID: PMC3593185 DOI: 10.1111/jfd.12054] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 10/05/2012] [Accepted: 10/17/2012] [Indexed: 05/10/2023]
Abstract
Sea lice infestation as a source of marine mortality of outwardly migrating Atlantic salmon smolts has been investigated by treating groups of ranched salmon, prior to release, with a prophylactic sea lice treatment conferring protection from sea lice infestation. A number of studies have been carried out in Ireland using both established ranched populations and groups of hatchery reared fish imprinted for 5-8 weeks in the sites of experimental releases. In this study, data on 352 142 migrating salmon from twenty-eight releases, at eight locations along Ireland's South and West coasts covering a 9-year period (2001 to 2009) are reviewed. Both published and new data are presented including a previously unpublished time series. The results of a meta-analysis of the combined data suggest that while sea lice-induced mortality on outwardly migrating smolts can be significant, it is a minor and irregular component of marine mortality in the stocks studied and is unlikely to be a significant factor influencing conservation status of salmon stocks.
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Sea lice levels on wild Atlantic salmon, Salmo salar L., returning to the coast of Ireland. JOURNAL OF FISH DISEASES 2013; 36:293-298. [PMID: 23297706 DOI: 10.1111/jfd.12059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 10/24/2012] [Accepted: 10/25/2012] [Indexed: 06/01/2023]
Abstract
The sea lice population structure, prevalence and intensity of Lepeophtheirus salmonis have been studied over a period extending from 2004 to 2011. Infestation data were collected from the interceptor drift net fishery from 2004 until it was closed in 2006. From 2010, data were collected from the inshore draft net fishery. In all, 34 samples from the drift and draft net fisheries have been analysed to date. Prevalence of infestation with L. salmonis regularly approached 100% in samples of hosts recovered from the offshore drift net fishery. Abundance was variable both within and between years with a maximum mean abundance of 25.8 lice per fish recorded in 2004. The population structure of L. salmonis on hosts recovered in the inshore and estuarine draft net fisheries was different from that observed in the more offshore drift net samples. There is clear evidence of recent infestation with L. salmonis in the draft net samples.
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Abstract
Community-based studies suggest that cannabis products that are high in Δ⁹-tetrahydrocannabinol (THC) but low in cannabidiol (CBD) are particularly hazardous for mental health. Laboratory-based studies are ideal for clarifying this issue because THC and CBD can be administered in pure form, under controlled conditions. In a between-subjects design, we tested the hypothesis that pre-treatment with CBD inhibited THC-elicited psychosis and cognitive impairment. Healthy participants were randomised to receive oral CBD 600 mg (n=22) or placebo (n=26), 210 min ahead of intravenous (IV) THC (1.5 mg). Post-THC, there were lower PANSS positive scores in the CBD group, but this did not reach statistical significance. However, clinically significant positive psychotic symptoms (defined a priori as increases ≥ 3 points) were less likely in the CBD group compared with the placebo group, odds ratio (OR)=0.22 (χ²=4.74, p<0.05). In agreement, post-THC paranoia, as rated with the State Social Paranoia Scale (SSPS), was less in the CBD group compared with the placebo group (t=2.28, p<0.05). Episodic memory, indexed by scores on the Hopkins Verbal Learning Task-revised (HVLT-R), was poorer, relative to baseline, in the placebo pre-treated group (-10.6 ± 18.9%) compared with the CBD group (-0.4% ± 9.7 %) (t=2.39, p<0.05). These findings support the idea that high-THC/low-CBD cannabis products are associated with increased risks for mental health.
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Effect of D-amino acid oxidase activator (DAOA; G72) on brain function during verbal fluency. Hum Brain Mapp 2012; 33:143-53. [PMID: 21391259 PMCID: PMC6870192 DOI: 10.1002/hbm.21198] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 10/17/2010] [Accepted: 10/18/2010] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The D-Amino acid oxidase activator (G72 or DAOA) is believed to play a key role in the regulation of central glutamatergic transmission which is seen to be altered in psychosis. It is thought to regulate D-amino acid oxidase (DAO), which metabolizes D-serine, a co-agonist of NMDA-type glutamate receptors and to be involved in dendritic arborization. Linkage, genetic association and expression studies have implicated the G72 gene in both schizophrenia and bipolar disorder. AIMS To examine the influence of G72 variation on brain function in the healthy population. METHOD Fifty healthy volunteers were assessed using functional magnetic resonance imaging while performing a verbal fluency task. Regional brain activation and task-dependent functional connectivity during word generation was compared between different rs746187 genotypes. RESULTS G72 rs746187 genotype had a significant effect on activation in the left postcentral and supramarginal gyri (FWE P < 0.05), and on the task-dependent functional coupling of this region with the retrosplenial cingulate gyrus (FWE P < 0.05). CONCLUSIONS Our results may reflect an effect of G72 on glutamatergic transmission, mediated by an influence on D-amino acid oxidase activity, on brain areas particularly relevant to the hypoglutamatergic model of psychosis.
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Disease-associated epigenetic changes in monozygotic twins discordant for schizophrenia and bipolar disorder. Hum Mol Genet 2011; 20:4786-96. [PMID: 21908516 PMCID: PMC3221539 DOI: 10.1093/hmg/ddr416] [Citation(s) in RCA: 312] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Studies of the major psychoses, schizophrenia (SZ) and bipolar disorder (BD), have traditionally focused on genetic and environmental risk factors, although more recent work has highlighted an additional role for epigenetic processes in mediating susceptibility. Since monozygotic (MZ) twins share a common DNA sequence, their study represents an ideal design for investigating the contribution of epigenetic factors to disease etiology. We performed a genome-wide analysis of DNA methylation on peripheral blood DNA samples obtained from a unique sample of MZ twin pairs discordant for major psychosis. Numerous loci demonstrated disease-associated DNA methylation differences between twins discordant for SZ and BD individually, and together as a combined major psychosis group. Pathway analysis of our top loci highlighted a significant enrichment of epigenetic changes in biological networks and pathways directly relevant to psychiatric disorder and neurodevelopment. The top psychosis-associated, differentially methylated region, significantly hypomethylated in affected twins, was located in the promoter of ST6GALNAC1 overlapping a previously reported rare genomic duplication observed in SZ. The mean DNA methylation difference at this locus was 6%, but there was considerable heterogeneity between families, with some twin pairs showing a 20% difference in methylation. We subsequently assessed this region in an independent sample of postmortem brain tissue from affected individuals and controls, finding marked hypomethylation (>25%) in a subset of psychosis patients. Overall, our data provide further evidence to support a role for DNA methylation differences in mediating phenotypic differences between MZ twins and in the etiology of both SZ and BD.
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Abstract
OBJECTIVES Gamma oscillations have been proposed to play an important role in neural information coding. There have been a limited number of electrophysiology studies in evoked gamma band responses (GBRs) in bipolar disorder (BPD). It is also unclear whether GBR deficits, if present, are potential endophenotypes for BPD as little is known about the heritability of GBRs. The present study aimed to examine whether GBRs derived from two auditory tasks, the oddball task and the dual-click paradigm, are potential BPD endophenotypes. METHODS A total of 308 subjects were included in this study: 198 healthy controls, 59 BPD patients (22 monozygotic BPD twins and 37 BPD patients from 31 families), and 51 unaffected relatives. The evoked gamma responses were calculated using a Morlet wavelet transformation. Structural equation modelling was applied to obtain the genetic (heritability) and environment estimates in each GBR variable and their (genetic) overlap with BPD. RESULTS The heritability estimates of GBR to standard stimuli were 0.51 and 0.35 to target stimuli in the oddball task. However, neither response type was impaired in BPD patients or their unaffected relatives. The heritability estimates of GBR to S1 stimuli were 0.54 and 0.50 to S2 stimuli in the dual-click paradigm. BPD patients had reduced gamma power and suppression to S1 stimuli but their unaffected relatives did not. CONCLUSIONS Evoked GBRs are heritable traits. However, GBR deficits are not observed in clinically unaffected relatives nor associated with BPD. Gamma responses do not appear to satisfy criteria for being BPD endophenotypes.
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No association of Disrupted-in-Schizophrenia-1 variation with prefrontal function in patients with schizophrenia and bipolar disorder. GENES BRAIN AND BEHAVIOR 2010; 10:276-85. [PMID: 21091867 DOI: 10.1111/j.1601-183x.2010.00665.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The Disrupted-in-Schizophrenia-1 (DISC1) gene has been implicated in both schizophrenia and bipolar disorder by linkage and genetic association studies. Altered prefrontal cortical function is a pathophysiological feature of both disorders, and we have recently shown that variation in DISC1 modulates prefrontal activation in healthy volunteers. Our goal was to examine the influence of the DISC1 polymorphism Cys704Ser on prefrontal function in schizophrenia and bipolar disorder. From 2004 to 2008, patients with schizophrenia (N = 44), patients with bipolar disorder (N = 35) and healthy volunteers (N = 53) were studied using functional magnetic resonance imaging while performing a verbal fluency task. The effect of Cys704Ser on cortical activation was compared between groups as Cys704 carriers vs. Ser704 homozygotes. In contrast to the significant effect on prefrontal activation we had previously found in healthy subjects, no significant effect of Cys704Ser was detected in this or any other region in either the schizophrenia or bipolar groups. When controls were compared with patients with schizophrenia, there was a diagnosis by genotype interaction in the left middle/superior frontal gyrus [family-wise error (FWE) P = 0.002]. In this region, Ser704/ser704 controls activated more than Cys704 carriers, and there was a trend in the opposite direction in schizophrenia patients. In contrast to its effect in healthy subjects, variation in DISC1 Cys704Ser704 genotype was not associated with altered prefrontal activation in patients with schizophrenia or bipolar disorder. The absence of an effect in patients may reflect interactions of the effects of DISC1 genotype with the effects of other genes associated with these disorders, and/or with the effects of the disorders on brain function.
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Core neuropsychological characteristics of children and adolescents with 22q11.2 deletion. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 2010; 54:701-713. [PMID: 20561146 DOI: 10.1111/j.1365-2788.2010.01298.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
BACKGROUND The 22q11.2 deletion syndrome (22qDS) confers high risk for intellectual disability and neuropsychological/academic impairment, although a minority of patients show average intelligence. Intellectual heterogeneity and the high prevalence of psychiatric diagnoses in earlier studies may have obscured the prototypical neuropsychological profile in 22qDS. METHODS We examined intelligence, memory, reading and mathematical processes in 31 children/adolescents with 22qDS, selected for educational underachievement and an absence of psychiatric diagnoses, using standardised, psychometrically matched instruments that specify how typical a score is for a given intelligence quotient (IQ). RESULTS Corroborating earlier findings, verbal IQ was significantly superior to performance IQ; verbal memory and basic reading were relative strengths; and visual/spatial memory was a relative weakness. All four findings transcended performance characteristics that are typical of low-IQ individuals. Rote learning yielded the highest score; reading comprehension, numerical operations and mathematical reasoning were among the lowest-performed academic domains. Albeit in the expected direction, performance in the respective components could not be clearly differentiated from what is IQ-appropriate. CONCLUSIONS A superiority of verbal intelligence over non-verbal intelligence, relative strengths in verbal memory and basic reading, and a relative weakness in visual/spatial memory are likely to be core characteristics of children/adolescents with 22qDS, transcending performance features that are typical of individuals with low IQ.
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S34-03 - Iffusion tensor imaging analyses of twins with and without schizophrenia. Eur Psychiatry 2010. [DOI: 10.1016/s0924-9338(10)70097-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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PW01-153 - Effect of DAAO on regional brain function in healthy individuals and patients with schizophrenia and bipolar disorder. Eur Psychiatry 2010. [DOI: 10.1016/s0924-9338(10)71552-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Increased inferior frontal activation during word generation: a marker of genetic risk for schizophrenia but not bipolar disorder? Hum Brain Mapp 2009; 30:3287-98. [PMID: 19479729 DOI: 10.1002/hbm.20749] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
During verbal-fluency tasks, impairments in performance and functional abnormalities in the inferior frontal cortex have been observed in both schizophrenia patients and their unaffected relatives. We sought to examine whether such functional abnormalities are a specific marker of genetic vulnerability to schizophrenia. We studied a sample of 132 subjects, comprising 39 patients with schizophrenia, 10 unaffected monozygotic (MZ) cotwins of schizophrenia probands, 28 patients with bipolar disorder, 7 unaffected MZ cotwins of bipolar disorder probands and 48 healthy controls. Blood oxygen level-dependent response was measured using functional magnetic resonance imaging during the performance of an overt verbal-fluency task with two levels of task difficulty, in a cytoarchitectonic region of interest encompassing Brodmann areas 44 and 45 bilaterally. Patients with schizophrenia and the unaffected MZ cotwins of schizophrenia probands showed increased activation in the inferior frontal cortex relative to healthy controls and bipolar patients. Increased engagement of the inferior frontal cortex during verbal-fluency may thus be a marker of genetic vulnerability to schizophrenia.
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White Matter Abnomalities in Twins with Bipolar Disorder and their Unaffected Cotwins. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)70095-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Opposite effects of catechol-O-methyltransferase Val158Met on cortical function in healthy subjects and patients with schizophrenia. Biol Psychiatry 2009; 65:473-80. [PMID: 19054502 DOI: 10.1016/j.biopsych.2008.09.027] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2008] [Revised: 07/31/2008] [Accepted: 09/03/2008] [Indexed: 10/21/2022]
Abstract
BACKGROUND Catechol-O-methyltransferase (COMT) is essential for dopamine metabolism in the brain, and normal variation in the COMT Val158Met polymorphism can influence regional brain function during cognitive tasks. How this is affected when central dopamine function is perturbed is unclear. We addressed this by comparing the effects of COMT Val158Met genotype on cortical activation during a task of executive functions in healthy and schizophrenic subjects. METHODS We studied 90 subjects comprising 48 healthy volunteers (15 Met158/Met158, 20 Val158/Met158, and 13 Val158/Val158) and 42 patients with DSM-IV schizophrenia (13 Met158/Met158, 17 Val158/Met158, and 12 Val158/Val158). Subjects were studied with functional magnetic resonance imaging while performing a verbal fluency task, with performance recorded online. Main effects of genotype and diagnosis and their interaction on cortical activation and functional connectivity were assessed using SPM5. RESULTS In the right peri-Sylvian cortex, the Met158 allele of the COMT Val158Met polymorphism was associated with greater activation than the Val158 allele in control subjects; the converse applied in patients (Z = 4.3; false discovery rate p = .04). There was also a strong trend for a group x genotype interaction on functional connectivity between this right peri-Sylvian region and the left anterior insula/operculum (Z = 3.4; p < .001, uncorrected). These findings were independent of between-group differences in task performance, medication, demographic factors, or IQ. CONCLUSIONS Frontotemporal function during verbal generation is modulated by variation in COMT genotype. This effect is altered in schizophrenia, which may reflect the perturbation of central dopamine function associated with the disorder.
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Abstract
We analysed Stroop (neuropsychological screening test) measures of response inhibition in 18 twin pairs discordant for bipolar I disorder compared with 17 healthy control pairs, as well as 40 singletons with bipolar disorder with psychotic features and a family history of psychosis, 46 of their first-degree relatives without bipolar disorder or psychosis and 48 controls. In both studies, individuals with bipolar disorder showed Stroop deficits and their first-degree relatives showed intact performance. In the twin patients, an interference score was associated with depressive symptoms. Having a first-degree relative with bipolar disorder, even a familial, psychotic form, did not confer risk for enhanced susceptibility to interference in our studies.
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Effects of the DAT 3’UTR VNTR Genotype on Brain Function in Healthy Subjects and Patients with Schizophrenia. Eur Psychiatry 2009. [DOI: 10.1016/s0924-9338(09)70932-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Aims:To examine the effect of a polymorphism in the Dopamine Transporter (DAT) gene on brain activation during executive function and, for the first time:1.determine the extent to which this is altered in schizophrenia and2.use a verbal fluency paradigm.This is relevant since:1.DAT plays a key role in the regulation of dopamine, which modulates cortical activation during cognitive tasks and2.a disruption of dopamine function is a fundamental pathophysiological feature of schizophrenia.Method:Functional magnetic resonance imaging was used to measure whole-brain responses during overt verbal fluency in 85 subjects: 44 healthy volunteers and 41 DSM-IV schizophrenia patients. Main effects of genotype and diagnostic group on activation and their interaction were estimated using an ANOVA in SPM5.Results:The 10-repeat allele of the 3'UTR VNTR was associated with greater activation than the 9-repeat allele in the left (Z=4.8; FWEp=0.005) and right (Z=4.2; FWEp=0.057) anterior insula and with decreased activation in the rostral anterior cingulate (Z=4.3 FWEp=0.04) during word generation (versus baseline). These effects were irrespective of diagnostic group but generally more marked in patients. There were also strong trends for groupxgenotype interactions in the left middle frontal gyrus and the left nucleus accumbens. Analysis was controlled for task performance, IQ, antipsychotic medication, psychopathology and demographics.Conclusion:Cortical function during executive tasks is normally modulated by variation in the DAT gene, effect which is dependent on the brain region. DAT's effect may be altered in schizophrenia patients, which may reflect altered central dopamine function.
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The effects of neuregulin1 on brain function in controls and patients with schizophrenia and bipolar disorder. Neuroimage 2008; 42:817-26. [PMID: 18585932 DOI: 10.1016/j.neuroimage.2008.05.025] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 05/16/2008] [Accepted: 05/19/2008] [Indexed: 12/25/2022] Open
Abstract
Recent studies have identified neuregulin1 as a probable susceptibility gene for schizophrenia and bipolar disorder. However, little is known about how this gene may affect brain function to increase vulnerability to these disorders. The present investigation examined the impact of neuregulin1 genotype on brain function in patients with schizophrenia, patients with bipolar I disorder and healthy volunteers. We used functional magnetic resonance imaging to measure brain responses during a verbal fluency task in a total of 115 subjects comprising 41 patients with schizophrenia, 29 patients with bipolar disorder and 45 healthy volunteers. We then used statistical parametric mapping to estimate the main effects of diagnostic group, the main effect of genotype and their interaction. We tested the hypothesis that the high-risk variant of neuregulin1 would be associated with altered prefrontal function. In all three diagnostic groups, the high-risk variant of neuregulin1 was associated with greater deactivation in the left precuneus. In addition, there was an interaction between diagnosis and genotype in two regions of the prefrontal cortex. The right inferior frontal gyrus expressed increased activation in individuals with the high-risk variant, but only in patients with schizophrenia. Conversely, the right posterior orbital gyrus expressed increased activation in individuals with the high-risk variant, but only in patients with bipolar disorder. Our results suggest that genetic variation in neuregulin1 has a measurable impact on brain function and provide preliminary evidence for a disease-specific pattern of gene action in different regions of the prefrontal cortex.
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Abstract
BACKGROUND Electrophysiological endophenotypes are far less explored in bipolar disorder as compared to schizophrenia. No previous twin study of event-related potentials (ERPs) in bipolar illness has been reported. This study uses a twin design and advanced genetic model fitting analyses aiming to (1) assess and quantify the relationship of a range of ERP components with bipolar disorder with psychotic features, and (2) examine the source of the relationship (due to genetic or environmental factors). METHOD P300, P50 suppression and mismatch negativity (MMN) were recorded in 10 discordant monozygotic (MZ) bipolar twin pairs, six concordant MZ bipolar twin pairs and 78 control twin pairs. Statistical analyses were based on structural equation modelling. RESULTS Bipolar disorder was significantly associated with smaller P300 amplitude and decreased P50 suppression. Genetic correlations were the main source of the associations, estimated to be -0 x 33 for P300 amplitude and 0 x 46 for P50 ratio. Individual-specific environmental influences were not significant. MMN and P300 latency were not associated with the illness. CONCLUSIONS The results provide supporting evidence that P300 amplitude and P50 suppression ratio are ERP endophenotypes for bipolar disorder.
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Volume of interfibre spaces in frog muscle and the calculation of concentrations in the fibre water. J Physiol 2007; 99:401-14. [PMID: 16995261 PMCID: PMC1394100 DOI: 10.1113/jphysiol.1941.sp003911] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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The influence of the reaction of blood plasma on oxygen consumption in relation to the law of isodynamic equivalence. J Physiol 2007; 91:48-58. [PMID: 16994918 PMCID: PMC1395233 DOI: 10.1113/jphysiol.1937.sp003543] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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[Association of extrauterine and intrauterine pregnancy: 3 cases]. LE MALI MEDICAL 2006; 21:35-38. [PMID: 19437844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Extra uterine pregnancy (GEU) constitutes, by its frequency a problem of public health, by its gravity an obstetric emergency and a problem of fertility for the woman. It represents the chief reason of maternal death during the first quarter of pregnancy. The association of extra-uterine and intra-uterine pregnancy is a particular case of twin pregnancy said ditopic. It is rare, but non exceptional. The authors bring three cases to remind us of its existence.
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Etiology of urethral discharge in West Africa: the role of Mycoplasma genitalium and Trichomonas vaginalis. Bull World Health Organ 2001; 79:118-26. [PMID: 11242818 PMCID: PMC2566348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
OBJECTIVE To determine the etiological role of pathogens other than Neisseria gonorrhoeae and Chlamydia trachomatis in urethral discharge in West African men. METHODS Urethral swabs were obtained from 659 male patients presenting with urethral discharge in 72 primary health care facilities in seven West African countries, and in 339 controls presenting for complaints unrelated to the genitourinary tract. Polymerase chain reaction analysis was used to detect the presence of N. gonorrhoeae, C. trachomatis, Trichomonas vaginalis, Mycoplasma genitalium, and Ureaplasma urealyticum. FINDINGS N. gonorrhoeae, T. vaginalis, C. trachomatis, and M. genitalium--but not U. urealyticum--were found more frequently in men with urethral discharge than in asymptomatic controls, being present in 61.9%, 13.8%, 13.4% and 10.0%, respectively, of cases of urethral discharge. Multiple infections were common. Among patients with gonococcal infection, T. vaginalis was as frequent a coinfection as C. trachomatis. M. genitalium, T. vaginalis, and C. trachomatis caused a similar clinical syndrome to that associated with gonococcal infection, but with a less severe urethral discharge. CONCLUSIONS M. genitalium and T. vaginalis are important etiological agents of urethral discharge in West Africa. The frequent occurrence of multiple infections with any combination of four pathogens strongly supports the syndromic approach. The optimal use of metronidazole in flowcharts for the syndromic management of urethral discharge needs to be explored in therapeutic trials.
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The absent patient: a meditation on a Chardin painting. Camb Q Healthc Ethics 2000; 9:6-16. [PMID: 10721465 DOI: 10.1017/s0963180100901026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
“Monsieur Chardin is obliged to keep his
subject before his eyes.” That remark, by a long
forgotten critic, was meant as a rebuke for the painter
who did not work from sketches. Jean Simeon Chardin's
counter, “We have to teach our eyes to look.”
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[Evaluation of atherogenic risk in homozygous sickle cell disease: study of lipid and apolipoprotein AI and B plasma levels]. BULLETIN DE LA SOCIETE DE PATHOLOGIE EXOTIQUE (1990) 1996; 89:278-81. [PMID: 9053050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The main clinical use of measurements of Apo Al and Apo B is to determine a patient's risk status for the development of ischemic heart disease. Apo B is generally accepted as a contributory cause of coronary artery disease, while Apo Al apparently has a protective effect. The present study reports the plasma change of Apo Al and B in sickle cell anaemic subjects. Immunochemical findings revealed that Apo Al and B levels were found to be lower in sickle cell patients as compared with normal subjects (HbAA). The atherogenicity index given by Apo B/Apo Al remained in the normal range during periods of steady state (0.64 +/- 0.28), while subjects in painful crisis had high index values (0.95 +/- 0.35). Therefore, we concluded that epidemiological studies on a large sample of patients are needed to confirm this relationship between painful crisis and risk of developing coronary artery disease.
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Abstract
OBJECTIVES To assess temporary expatriation as a risk factor for HIV infection in a rural area of Senegal and to examine the transmission of HIV from expatriates to their families. DESIGN Cross-sectional study in identified expatriates and in a representative cluster sample of the general population from the same geographical area in northern Senegal. METHODS In 1989, a survey (including questionnaire and serological tests for HIV-1 and HIV-2) was conducted in all expatriates currently living in 11 villages in northern Senegal and spouses of all expatriates (present or not) from this area ('expatriate' group, n = 258). In parallel, a cluster sample of 600 adults was drawn from eight villages of the same area, of whom 414 were selected as the control group since they and their spouses had not travelled outside Senegal in the last 10 years. RESULTS In the 'expatriate' group, sera from 39 subjects were confirmed as HIV-positive by Western blot [17 out of 63 men (27.0%) and 22 out of 195 women (11.3%)]. Of these subjects, 33 were infected by HIV-1, four by HIV-2 and two had a dual HIV-1/2 profile. In contrast, only two subjects (one man and one woman) from the control group were infected by HIV-2 and none by HIV-1. In men, HIV-1 seroprevalence was associated with age < 40 years [odds ratio (OR), 7.4; P = 0.03] and previous sexually transmitted disease (STD) symptoms (OR, 13.5; P = 0.03), whereas the risk factors in women were age < 25 years (OR, 3.7; P = 0.04), being a widow (OR, 30.4; P < 0.01) and presence of sexual activity over the last 2 years (OR, 21.3; P < 0.01). CONCLUSIONS Penetration of HIV-1 infection in a country where HIV-2 is endemic shows that the HIV-1 epidemic is currently spreading to rural West Africa. Migrant workers appear to play a major role in this epidemic.
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Abstract
The distribution of electrical self-stimulation foci within the amygdala (AMY) was mapped using movable electrodes in rats. Each barpress delivered a 0.4-s train of cathodal rectangular pulses of fixed intensity and duration and variable frequency. The rate-frequency function was recorded for successive dorsoventral sites. Self-stimulation was found throughout the AMY, except in the lateral nucleus. Depending on the site, maximum rates varied from 3 to 37 barpresses/min, whereas threshold frequencies varied from 9.2 to 40 pulses/train; no correlation between these two aspects of self-stimulation was found. Most threshold frequencies lay within the range of 10 to 20 pulses/train, which suggests a relatively homogeneous distribution of rewarding efficacy within the positive areas. The lowest threshold estimates are comparable to those usually obtained for pontine and medial forebrain bundle areas, which suggests that the AMY is an important focus for self-stimulation.
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Abstract
The function relating bar-pressing rate to the frequency of cathodal pulses was obtained in rats self-stimulating with amygdaloid (AMY) and lateral hypothalamic (LH) electrodes. The maximum self-stimulation (SS) rates in the AMY was found to be very low, compared to the LH. Concurrent stimulation with pairs of AMY-LH pulses did not shift the rate-frequency functional laterally, indicating the absence of summation of the two rewarding effects. In a second experiment, concurrent AMY-LH stimulation (using sub-threshold intensity LH pulses) facilitated bar-pressing for AMY stimulation (it increased the slope of the AMY rate-frequency function) without shifting this function laterally. In a third experiment, subjects were given a choice between a pulse frequency yielding maximal AMY rate and a series of higher pulse frequencies. Subjects consistently preferred the higher frequency values, attesting that the maximum AMY rates were not constrained by a saturating reinforcing effect. In a fourth experiment, subjects were given a choice between AMY stimulation and concurrent AMY-LH stimulation, using low intensity LH pulses. Subjects showed no preference for either stimulation condition, although rates were higher for the latter condition. These findings suggest that the maximum rate for AMY stimulation was constrained by factors interfering with bar-pressing and that the effect of these factors was attenuated by co-activation of the LH. In a fifth experiment, pre-treatment with phenobarbital mimicked the rate-enhancing effect of concurrent AMY-LH stimulation for 2 of the 4 subjects tested. This finding suggests that the LH pulses contributed to attenuate seizure activity accompanying AMY SS. In a final experiment, AMY SS rates were also increased by co-activation of rewarding sites in the rostral MFB but not the dorsal raphe, suggesting an anatomical specificity of this effect.
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Abstract
The distribution of electrical self-stimulation foci within the amygdala (AMY) was mapped using movable electrodes in rats. Each barpress delivered a 0.4-s train of cathodal rectangular pulses of fixed intensity and duration and variable frequency. The rate-frequency function was recorded for successive dorsoventral sites. Self-stimulation was found throughout the AMY, except in the lateral nucleus. Depending on the site, maximum rates varied from 3 to 37 barpresses/min, whereas threshold frequencies varied from 9.2 to 40 pulses/train; no correlation between these two aspects of self-stimulation was found. Most threshold frequencies lay within the range of 10 to 20 pulses/train, which suggests a relatively homogeneous distribution of rewarding efficacy within the positive areas. The lowest threshold estimates are comparable to those usually obtained for pontine and medial forebrain bundle areas, which suggests that the AMY is an important focus for self-stimulation.
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