1,900 research outputs found
Individual and area-level risk factors for suicidal ideation and attempt in people with severe depression
INTRODUCTION: Previous research has identified several risk factors that are strongly associated with suicidal behavior in patients with severe depression. However, the effects of area-level characteristics on suicidal ideation and attempt in this population remain unclear. METHODS: The Clinical Record Interactive Search (CRIS) database was used to identify 2587 patients with severe depression who received secondary mental health services from the Camden & Islington NHS Foundation Trust. Stepwise multivariable logistic regression models were used to examine associations between socio-demographic characteristics, clinical variables, area-level measures, and suicidal ideation and attempt as separate outcomes. RESULTS: Both suicidal ideation and attempts were common among this cohort of severely depressed individuals (70.5% and 37.7%, respectively). While several individual socio-demographic and clinical characteristics were associated with both outcomes, particularly past psychiatric admission (suicidal ideation: adjusted OR=2.86, 95% CI: 2.26-3.62; suicide attempt: adjusted OR=4.00, 95% CI: 3.30-4.89), neither social deprivation nor ethnic density (measured at the area-level) was associated with risk for either outcome. LIMITATIONS: Data were not collected specifically for research purposes and hence information on some potential confounders was not available. Additionally, information was restricted to individuals who accessed secondary mental health services in a defined catchment area and period. The study therefore does not take into account individuals who did not access mental health services. CONCLUSIONS: The variation in risk for suicidal ideation and attempt among severely depressed individuals is explained by differences in individual socio-demographic and clinical characteristics, most notably past psychiatric admission and substance misuse, and not by area-level measures
Self-harm, Unintentional Injury, and Suicide in Bipolar Disorder During Maintenance Mood Stabilizer Treatment: A UK Population-Based Electronic Health Records Study
Importance: Self-harm is a prominent cause of morbidity in patients with bipolar disorder and is strongly associated with suicide. There is evolving evidence that lithium use may reduce suicidal behavior, in addition to concerns that the use of anticonvulsants may increase self-harm. Information is limited about the effects of antipsychotics when used as mood stabilizer treatment. Rates of unintentional injury are poorly defined in bipolar disorder, and understanding drug associations with this outcome may shed light on mechanisms for lithium's potential antisuicidal properties through reduction in impulsive aggression. Objective: To compare rates of self-harm, unintentional injury, and suicide in patients with bipolar disorder who were prescribed lithium, valproate sodium, olanzapine, or quetiapine fumarate. Design, Setting, and Participants: This investigation was a propensity score (PS)-adjusted and PS-matched longitudinal cohort study in a nationally representative UK sample using electronic health records data collected between January 1, 1995, and December 31, 2013. Participants included all patients diagnosed as having bipolar disorder who were prescribed lithium, valproate, olanzapine, or quetiapine as maintenance mood stabilizer treatment. Main Outcomes and Measures: The primary outcome was any form of self-harm. Secondary outcomes were unintentional injury and suicide. Results: Of the 14β―396 individuals with a diagnosis of BPD, 6671 were included in the cohort, with 2148 prescribed lithium, 1670 prescribed valproate, 1477 prescribed olanzapine, and 1376 prescribed quetiapine as maintenance mood stabilizer treatment. Self-harm rates were lower in patients prescribed lithium (205; 95% CI, 175-241 per 10β―000 person-years at risk [PYAR]) compared with those prescribed valproate (392; 95% CI, 334-460 per 10β―000 PYAR), olanzapine (409; 95% CI, 345-483 per 10β―000 PYAR), or quetiapine (582; 95% CI, 489-692 per 10β―000 PYAR). This association was maintained after PS adjustment (hazard ratio [HR], 1.40; 95% CI, 1.12-1.74 for valproate, olanzapine, or quetiapine vs lithium) and PS matching (HR, 1.51; 95% CI, 1.21-1.88). After PS adjustment, unintentional injury rates were lower for lithium compared with valproate (HR, 1.32; 95% CI, 1.10-1.58) and quetiapine (HR, 1.34; 95% CI, 1.07-1.69) but not olanzapine. The suicide rate in the cohort was 14 (95% CI, 9-21) per 10β―000 PYAR. Although this rate was lower in the lithium group than for other treatments, there were too few events to allow accurate estimates. Conclusions and Relevance: Patients taking lithium had reduced self-harm and unintentional injury rates. This finding augments limited trial and smaller observational study results. It supports the hypothesis that lithium use reduces impulsive aggression in addition to stabilizing mood
Transmit Power Minimization for MIMO Systems of Exponential Average BER with Fixed Outage Probability
This document is the Accepted Manuscript version of the following article: Dian-Wu Yue, and Yichuang Sun, βTransmit Power Minimization for MIMO Systems of Exponential Average BER with Fixed Outage Probabilityβ, Wireless Personal Communications, Vol. 90 (4): 1951-1970, first available online on 20 June 2016. Under embargo. Embargo end date: 20 June 2017. The final publication is available at Springer via https://link.springer.com/article/10.1007%2Fs11277-016-3432-4This paper is concerned with a wireless multiple-antenna system operating in multiple-input multiple-output (MIMO) fading channels with channel state information being known at both transmitter and receiver. By spatiotemporal subchannel selection and power control, it aims to minimize the average transmit power (ATP) of the MIMO system while achieving an exponential type of average bit error rate (BER) for each data stream. Under the constraints on each subchannel that individual outage probability and average BER are given, based on a traditional upper bound and a dynamic upper bound of Q function, two closed-form ATP expressions are derived, respectively, which can result in two different power allocation schemes. Numerical results are provided to validate the theoretical analysis, and show that the power allocation scheme with the dynamic upper bound can achieve more power savings than the one with the traditional upper bound.Peer reviewe
Use of partial least squares regression to impute SNP genotypes in Italian Cattle breeds
Background
The objective of the present study was to test the ability of the partial least squares regression technique to impute genotypes from low density single nucleotide polymorphisms (SNP) panels i.e. 3K or 7K to a high density panel with 50K SNP. No pedigree information was used.
Methods
Data consisted of 2093 Holstein, 749 Brown Swiss and 479 Simmental bulls genotyped with the Illumina 50K Beadchip. First, a single-breed approach was applied by using only data from Holstein animals. Then, to enlarge the training population, data from the three breeds were combined and a multi-breed analysis was performed. Accuracies of genotypes imputed using the partial least squares regression method were compared with those obtained by using the Beagle software. The impact of genotype imputation on breeding value prediction was evaluated for milk yield, fat content and protein content.
Results
In the single-breed approach, the accuracy of imputation using partial least squares regression was around 90 and 94% for the 3K and 7K platforms, respectively; corresponding accuracies obtained with Beagle were around 85% and 90%. Moreover, computing time required by the partial least squares regression method was on average around 10 times lower than computing time required by Beagle. Using the partial least squares regression method in the multi-breed resulted in lower imputation accuracies than using single-breed data. The impact of the SNP-genotype imputation on the accuracy of direct genomic breeding values was small. The correlation between estimates of genetic merit obtained by using imputed versus actual genotypes was around 0.96 for the 7K chip.
Conclusions
Results of the present work suggested that the partial least squares regression imputation method could be useful to impute SNP genotypes when pedigree information is not available
A systematic review and meta-analysis of premature mortality in bipolar affective disorder
Objective
To review and complete meta-analysis of studies estimating standardised mortality ratios (SMRs) in bipolar affective disorder (BPAD) for all-cause and cause-specific mortalities.
Method
Cause-specific mortality was grouped into natural and unnatural causes. These subgroups were further divided into circulatory, respiratory, neoplastic and infectious causes, and suicide and other violent deaths. Summary SMRs were calculated using random-effects meta-analysis. Heterogeneity was examined via subgroup analysis and meta-regression.
Results
Systematic searching found 31 studies meeting inclusion criteria. Summary SMR for all-cause mortality = 2.05 (95% CI 1.89β2.23), but heterogeneity was high (I2 = 96.2%). This heterogeneity could not be accounted for by date of publication, cohort size, mid-decade of data collection, population type or geographical region. Unnatural death summary SMR = 7.42 (95% CI 6.43β8.55) and natural death = 1.64 (95% CI 1.47β1.83). Specifically, suicide SMR = 14.44 (95% CI 12.43β16.78), other violent death SMR = 3.68 (95% CI 2.77β4.90), deaths from circulatory disease = 1.73 (95% CI 1.54β1.94), respiratory disease = 2.92 (95% CI 2.00β4.23), infection = 2.25 (95% CI 1.70β3.00) and neoplasm = 1.14 (95% CI 1.10β1.21).
Conclusion
Despite considerable heterogeneity, all summary SMR estimates and a large majority of individual studies showed elevated mortality in BPAD compared to the general population. This was true for all causes of mortality studied
Weight change over two years in people prescribed olanzapine, quetiapine and risperidone in UK primary care: Cohort study in THIN, a UK primary care database
BACKGROUND: Follow-up studies of weight gain related to antipsychotic treatment beyond a year are limited in number. We compared weight change in the three most commonly prescribed antipsychotics in a representative UK General Practice database. METHOD: We conducted a cohort study in United Kingdom primary care records of people newly prescribed olanzapine, quetiapine or risperidone. The primary outcome was weight in each six month period for two years after treatment initiation. Weight changes were compared using linear regression, adjusted for age, baseline weight and diagnosis. RESULTS: N = 6338 people received olanzapine, 12,984 quetiapine and 6556 risperidone. Baseline weight was lowest for men treated with olanzapine (80.8 kg versus 83.5 kg quetiapine, 82.0 kg risperidone) and women treated with olanzapine (67.7 kg versus 71.5 kg quetiapine 68.4 kg risperidone. Weight gain occurred during treatment with all three drugs. Compared with risperidone mean weight gain was higher with olanzapine (adjusted co-efficient +1.24 kg (95% confidence interval: 0.69β1.79 kg per six months) for men and +0.77 kg (95% confidence interval: 0.29β1.24 kg) for women). Weight gain with quetiapine was lower in unadjusted models compared with risperidone, but this difference was not significant after adjustment. CONCLUSION: Olanzapine is more commonly prescribed to people with lower weight. However, after accounting for baseline weight, age, sex and diagnosis, olanzapine is still associated with greater weight gain over two years than risperidone or quetiapine. Baseline weight does not ameliorate the risks of weight gain associated with antipsychotic medication. Weight gain should be assertively discussed and managed for people prescribed antipsychotics, especially olanzapine
Wake response to an ocean-feedback mechanism: Madeira Island case study
This discussion focused on the numerical study of a wake episode. The Weather
Research and Forecasting model was used in a downscale mode. The current
literature focuses the discussion on the adiabatic dynamics of atmospheric
wakes. Changes in mountain height and consequently on its relation to the
atmospheric inversion layer should explain the shift in wake regimes: from a
'strong-wake' to a 'weak-wake' scenario. Nevertheless, changes in SST
variability can also induce similar regime shifts. Increase in evaporation,
contributes to increase convection and thus to an uplift of the stratified
atmospheric layer, above the critical height, with subsequent internal gravity
wave activity.Comment: Under review proces
A CI-Independent Form of Replicative Inhibition: Turn Off of Early Replication of Bacteriophage Lambda
Several earlier studies have described an unusual exclusion phenotype exhibited by cells with plasmids carrying a portion of the replication region of phage lambda. Cells exhibiting this inhibition phenotype (IP) prevent the plating of homo-immune and hybrid hetero-immune lambdoid phages. We have attempted to define aspects of IP, and show that it is directed to repΞ» phages. IP was observed in cells with plasmids containing a Ξ» DNA fragment including oop, encoding a short OOP micro RNA, and part of the lambda origin of replication, oriΞ», defined by iteron sequences ITN1-4 and an adjacent high AT-rich sequence. Transcription of the intact oop sequence from its promoter, pO is required for IP, as are iterons ITN3β4, but not the high AT-rich portion of oriΞ». The results suggest that IP silencing is directed to theta mode replication initiation from an infecting repΞ» genome, or an induced repΞ» prophage. Phage mutations suppressing IP, i.e., Sip, map within, or adjacent to cro or in O, or both. Our results for plasmid based IP suggest the hypothesis that there is a natural mechanism for silencing early theta-mode replication initiation, i.e. the buildup of Ξ» genomes with oop+
oriΞ»+ sequence
Reversible Keap1 inhibitors are preferential pharmacological tools to modulate cellular mitophagy
Mitophagy orchestrates the autophagic degradation of dysfunctional mitochondria preventing their pathological accumulation and contributing to cellular homeostasis. We previously identified a novel chemical tool (hereafter referred to as PMI), which drives mitochondria into autophagy without collapsing their membrane potential (ΞΞ¨m). PMI is an inhibitor of the protein-protein interaction (PPI) between the transcription factor Nrf2 and its negative regulator, Keap1 and is able to up-regulate the expression of autophagy-associated proteins, including p62/SQSTM1. Here we show that PMI promotes mitochondrial respiration, leading to a superoxide-dependent activation of mitophagy. Structurally distinct Keap1-Nrf2 PPI inhibitors promote mitochondrial turnover, while covalent Keap1 modifiers, including sulforaphane (SFN) and dimethyl fumarate (DMF), are unable to induce a similar response. Additionally, we demonstrate that SFN reverses the effects of PMI in co-treated cells by reducing the accumulation of p62 in mitochondria and subsequently limiting their autophagic degradation. This study highlights the unique features of Keap1-Nrf2 PPI inhibitors as inducers of mitophagy and their potential as pharmacological agents for the treatment of pathological conditions characterized by impaired mitochondrial quality control
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