Psychiatry - Research Publications

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    N-cadherin mediates plasticity-induced long-term spine stabilization
    Mendez, P ; De Roo, M ; Poglia, L ; Klauser, P ; Muller, D (ROCKEFELLER UNIV PRESS, 2010-05-03)
    Excitatory synapses on dendritic spines are dynamic structures whose stability can vary from hours to years. However, the molecular mechanisms regulating spine persistence remain essentially unknown. In this study, we combined repetitive imaging and a gain and loss of function approach to test the role of N-cadherin (NCad) on spine stability. Expression of mutant but not wild-type NCad promotes spine turnover and formation of immature spines and interferes with the stabilization of new spines. Similarly, the long-term stability of preexisting spines is reduced when mutant NCad is expressed but enhanced in spines expressing NCad-EGFP clusters. Activity and long-term potentiation (LTP) induction selectively promote formation of NCad clusters in stimulated spines. Although activity-mediated expression of NCad-EGFP switches synapses to a highly stable state, expression of mutant NCad or short hairpin RNA-mediated knockdown of NCad prevents LTP-induced long-term stabilization of synapses. These results identify NCad as a key molecular component regulating long-term synapse persistence.
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    Anti-inflammatory effects of antidepressant and atypical antipsychotic medication for the treatment of major depression and comorbid arthritis: a case report.
    Baune, BT ; Eyre, H (Springer Science and Business Media LLC, 2010-01-12)
    INTRODUCTION: This case report describes the effects of psychotropic treatment, quetiapine in particular, on systemic inflammation, pain, general functioning and major depression in the treatment of a woman with arthritis. CASE PRESENTATION: A 49-year-old Caucasian Australian woman with arthritis, pain and depression was treated with a course of escitalopram, mirtazapine and quetiapine. Pain levels, general functioning and degree of depressive symptoms were evaluated with a visual analogue scale. Systemic inflammation had been assessed by C-reactive protein serum levels since 2003. C-reactive protein levels, physical pain, symptoms of arthritis and depression decreased significantly during the past 12 months of treatment with quetiapine, while treatment with selective serotonin reuptake inhibitors and mirtazapine remained the same. CONCLUSIONS: We suggest that the treatment particularly with quetiapine may have anti-inflammatory effects in arthritis and comorbid major depression, which eventually led to a remission of pain and depression and to normal general function.
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    Bio-psychosocial determinants of time lost from work following non life threatening acute orthopaedic trauma.
    Clay, FJ ; Newstead, SV ; Watson, WL ; Ozanne-Smith, J ; McClure, RJ (Springer Science and Business Media LLC, 2010-01-05)
    BACKGROUND: To determine factors predicting the duration of time away from work following acute orthopaedic non life threatening trauma METHODS: Prospective cohort study conducted at four hospitals in Victoria, Australia. The cohort comprised 168 patients aged 18-64 years who were working prior to the injury and sustained a range of acute unintentional orthopaedic injuries resulting in hospitalization. Baseline data was obtained by survey and medical record review. Multivariate Cox proportional hazards regression analysis was used to examine the association between potential predictors and the duration of time away from work during the six month study. The study achieved 89% follow-up. RESULTS: Of the 168 participants recruited to the study, 68% returned to work during the six month study. Multivariate Cox proportional hazards regression analysis identified that blue collar work, negative pain attitudes with respect to work, high initial pain intensity, injury severity, older age, initial need for surgery, the presence of co-morbid health conditions at study entry and an orthopaedic injury to more than one region were associated with extended duration away from work following the injury. Participants in receipt of compensation who reported high social functioning at two weeks were 2.58 times more likely to have returned to work than similar participants reporting low social functioning. When only those who had returned to work were considered, the participant reported reason for return to work " to fill the day" was a significant predictor of earlier RTW [RR 2.41 (95% C.I 1.35-4.30)] whereas "financial security" and "because they felt able to" did not achieve significance. CONCLUSIONS: Many injury-related and psycho social factors affect the duration of time away from work following orthopaedic injury. Some of these are potentially modifiable and may be amenable to intervention. Further consideration of the reasons provided by participants for returning to work may provide important opportunities for social marketing approaches designed to alleviate the financial and social burden associated with work disability.
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    Infection control practices among hospital health and support workers in Hong Kong
    Chau, JPC ; Thompson, DR ; Lee, DTF ; Twinn, S (W B SAUNDERS CO LTD, 2010-08)
    A report by the Hong Kong government noted that hospital infection control standards were inadequate, requiring audit, development and implementation. In addition, hospital staff needed training in infection control measures. We investigated infection control practices among 162 hospital health workers (109 nurses, 45 doctors and 8 therapists) and 44 support workers in one acute hospital and two rehabilitation hospitals using a non-blinded, observational design. We examined compliance with isolation precautions and infection control guidelines, including proper wearing of a mask, goggles/face shield, or gown; handling patient care equipment, linen, and laundry; routine and terminal cleaning; and terminal cleaning of an isolation room. One major breakdown in compliance was use of sleeveless disposable plastic aprons instead of long-sleeved gowns during procedures likely to generate splashes or sprays of blood and body fluids. In more than half of the observed episodes, participants failed to disinfect medical devices, such as stethoscopes, before re-use. Thorough cleansing of commodes between patients was also lacking. Overall compliance with local and international infection control guidelines was satisfactory, but several aspects required improvement.
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    Network scaling effects in graph analytic studies of human resting-state fMRI data
    Fornito, A ; Zalesky, A ; Bullmore, ET (FRONTIERS MEDIA SA, 2010)
    Graph analysis has become an increasingly popular tool for characterizing topological properties of brain connectivity networks. Within this approach, the brain is modeled as a graph comprising N nodes connected by M edges. In functional magnetic resonance imaging (fMRI) studies, the nodes typically represent brain regions and the edges some measure of interaction between them. These nodes are commonly defined using a variety of regional parcellation templates, which can vary both in the volume sampled by each region, and the number of regions parcellated. Here, we sought to investigate how such variations in parcellation templates affect key graph analytic measures of functional brain organization using resting-state fMRI in 30 healthy volunteers. Seven different parcellation resolutions (84, 91, 230, 438, 890, 1314, and 4320 regions) were investigated. We found that gross inferences regarding network topology, such as whether the brain is small-world or scale-free, were robust to the template used, but that both absolute values of, and individual differences in, specific parameters such as path length, clustering, small-worldness, and degree distribution descriptors varied considerably across the resolutions studied. These findings underscore the need to consider the effect that a specific parcellation approach has on graph analytic findings in human fMRI studies, and indicate that results obtained using different templates may not be directly comparable.
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    Continuation treatment of major depressive disorder: is there a case for duloxetine?
    Norman, TR ; Olver, JS (DOVE MEDICAL PRESS LTD, 2010-02-12)
    Duloxetine is a serotonin-noradrenaline reuptake inhibitor with established efficacy for the short-term treatment of major depressive disorder. Efficacy in continuation treatment (greater than six months of continuous treatment) has been established from both open and placebo-controlled relapse prevention and comparative studies. Seven published studies were available for review and showed that in both younger and older populations (aged more than 65 years) the acute efficacy of duloxetine was maintained for up to one year. Response to treatment was based on accepted criteria for remission of depression and in continuation studies remission rates were greater than 70%. Comparative studies showed that duloxetine was superior to placebo and comparable to paroxetine and escitalopram in relapse prevention. Importantly a study of duloxetine in patients prone to relapse of major depressive disorder showed that the medication was more effective than placebo in this difficult to treat population. Side effects of duloxetine during continuation treatment were predictable on the basis of the known pharmacology of the drug. In particular there were no significant life-threatening events which emerged with continued use of the medication. On the other hand vigilance is required since the data base on which to judge very rare events is limited by the relatively low exposure to the drug. Duloxetine has established both efficacy and safety for continuation treatment but its place as a first-line treatment of relapse prevention requires further experience. In particular further comparative studies against established agents would be useful in deciding the place of duloxetine in therapy.
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    Differential effects of pre and post-payment on neurologists' response rates to a postal survey
    Kanaan, RAA ; Wessely, SC ; Armstrong, D (BIOMED CENTRAL LTD, 2010-10-25)
    BACKGROUND: Monetary incentives are an effective way of increasing response rates to surveys, though they are generally less effective in physicians, and are more effective when the incentive is paid up-front rather than when made conditional on completion. METHODS: In this study we examine the effectiveness of pre- and post-completion incentives on the response rates of all the neurologists in the UK to a survey about conversion disorder, using a cluster randomised controlled design. A postal survey was sent to all practicing consultant neurologists, in two rounds, including either a book token, the promise of a book token, or nothing at all. RESULTS: Three hundred and fifty-one of 591 eligible neurologists completed the survey, for a response rate of 59%. While the post-completion incentive exerted no discernible influence on response rates, a pre-completion incentive did, with an odds-ratio of 2.1 (95% confidence interval 1.5-3.0). CONCLUSIONS: We conclude that neurologists, in the UK at least, may be influenced to respond to a postal survey by a pre-payment incentive but are unaffected by a promised reward.
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    "The solution needs to be complex." Obese adults' attitudes about the effectiveness of individual and population based interventions for obesity
    Thomas, SL ; Lewis, S ; Hyde, J ; Castle, D ; Komesaroff, P (BMC, 2010-07-15)
    BACKGROUND: Previous studies of public perceptions of obesity interventions have been quantitative and based on general population surveys. This study aims to explore the opinions and attitudes of obese individuals towards population and individual interventions for obesity in Australia. METHODS: Qualitative methods using in-depth semi-structured telephone interviews with a community sample of obese adults (Body Mass Index >or=30). Theoretical, purposive and strategic recruitment techniques were used to ensure a broad sample of obese individuals with different types of experiences with their obesity. Participants were asked about their attitudes towards three population based interventions (regulation, media campaigns, and public health initiatives) and three individual interventions (tailored fitness programs, commercial dieting, and gastric banding surgery), and the effectiveness of these interventions. RESULTS: One hundred and forty two individuals (19-75 years) were interviewed. Participants strongly supported non-commercial interventions that were focused on encouraging individuals to make healthy lifestyle changes (regulation, physical activity programs, and public health initiatives). There was less support for interventions perceived to be invasive or high risk (gastric band surgery), stigmatising (media campaigns), or commercially motivated and promoting weight loss techniques (commercial diets and gastric banding surgery). CONCLUSION: Obese adults support non-commercial, non-stigmatising interventions which are designed to improve lifestyles, rather than promote weight loss.
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    Expression of the Rap1 Guanine Nucleotide Exchange Factor, MR-GEF, Is Altered in Individuals with Bipolar Disorder
    Bithell, A ; Hsu, T ; Kandanearatchi, A ; Landau, S ; Everall, IP ; Tsuang, MT ; Chana, G ; Williams, BP ; Domschke, K (PUBLIC LIBRARY SCIENCE, 2010-04-28)
    In the rodent forebrain GABAergic neurons are generated from progenitor cells that express the transcription factors Dlx1 and Dlx2. The Rap-1 guanine nucleotide exchange factor, MR-GEF, is turned on by many of these developing GABAergic neurons. Expression of both Dlx1/2 and MR-GEF is retained in both adult mouse and human forebrain where, in human, decreased Dlx1 expression has been associated with psychosis. Using in situ hybridization studies we show that MR-GEF expression is significantly down-regulated in the forebrain of Dlx1/2 double mutant mice suggesting that MR-GEF and Dlx1/2 form part of a common signalling pathway during GABAergic neuronal development. We therefore compared MR-GEF expression by in situ hybridization in individuals with major psychiatric disorders (schizophrenia, bipolar disorder, major depression) and control individuals. We observed a significant positive correlation between layers II and IV of the dorso-lateral prefrontal cortex (DLPFC) in the percentage of MR-GEF expressing neurons in individuals with bipolar disorder, but not in individuals with schizophrenia, major depressive disorder or in controls. Since MR-GEF encodes a Rap1 GEF able to activate G-protein signalling, we suggest that changes in MR-GEF expression could potentially influence neurotransmission.
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    The fitness for the Ageing Brain Study II (FABS II): protocol for a randomized controlled clinical trial evaluating the effect of physical activity on cognitive function in patients with Alzheimer's disease
    Cyarto, EV ; Cox, KL ; Almeida, OP ; Flicker, L ; Ames, D ; Byrne, G ; Hill, KD ; Beer, CD ; LoGiudice, D ; Appadurai, K ; Irish, M ; Renehan, E ; Lautenschlager, NT (BMC, 2010-12-10)
    BACKGROUND: Observational studies have documented a potential protective effect of physical exercise in older adults who are at risk for developing Alzheimer's disease. The Fitness for the Ageing Brain II (FABS II) study is a multicentre randomized controlled clinical trial (RCT) aiming to determine whether physical activity reduces the rate of cognitive decline among individuals with Alzheimer's disease. This paper describes the background, objectives of the study, and an overview of the protocol including design, organization and data collection methods. METHODS/DESIGN: The study will recruit 230 community-dwelling participants diagnosed with Alzheimer's disease. Participants will be randomly allocated to two treatment groups: usual care group or 24-week home-based program consisting of 150 minutes per week of tailored moderate physical activity. The primary outcome measure of the study is cognitive decline as measured by the change from baseline in the total score on the Alzheimer's disease Assessment Scale-Cognitive section. Secondary outcomes of interest include behavioral and psychological symptoms, quality of life, functional level, carer burden and physical function (strength, balance, endurance, physical activity). Primary endpoints will be measured at six and twelve months following the baseline assessment. DISCUSSION: This RCT will contribute evidence regarding the potential benefits of a systematic program of physical activity as an affordable and safe intervention for people with Alzheimer's disease. Further, if successful, physical activity in combination with usual care has the potential to alleviate the symptoms of Alzheimer's disease and improve its management and the quality of life of patients and their carers. TRIAL REGISTRATION: Australia New Zealand Clinical Trials Registry ACTRN12609000755235.