4,405 research outputs found

    Neuromedin U partially mediates leptin-induced hypothalamo-pituitary adrenal (HPA) stimulation and has a physiological role in the regulation of the HPA axis in the rat.

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    Intracerebroventricular (ICV) administration of the hypothalamic neuropeptide neuromedin U (NMU) or the adipostat hormone leptin increases plasma ACTH and corticosterone. The relationship between leptin and NMU in the regulation of the hypothalamo-pituitary adrenal (HPA) axis is currently unknown. In this study, leptin (1 nM) significantly increased the release of CRH from ex vivo hypothalamic explants by 207 ± 8.4% (P < 0.05 vs. basal), an effect blocked by the administration of anti-NMU IgG. The ICV administration of leptin (10 μg, 0.625 nmol) increased plasma ACTH and corticosterone 20 min after injection [plasma ACTH (picograms per milliliter): vehicle, 63 ± 20, leptin, 135 ± 36, P < 0.05; plasma corticosterone (nanograms per milliliter): vehicle, 285 ± 39, leptin, 452 ± 44, P < 0.01]. These effects were partially attenuated by the prior administration of anti-NMU IgG. Peripheral leptin also stimulated ACTH release, an effect attenuated by prior ICV administration of anti-NMU IgG. We examined the diurnal pattern of hypothalamic NMU mRNA expression and peptide content, plasma leptin, and plasma corticosterone. The diurnal changes in hypothalamic NMU mRNA expression were positively correlated with hypothalamic NMU peptide content, plasma corticosterone, and plasma leptin. The ICV administration of anti-NMU IgG significantly attenuated the dark phase rise in corticosterone [corticosterone (nanograms per milliliter): vehicle, 493 ± 38; NMU IgG, 342 ± 47 (P < 0.05)]. These studies suggest that NMU may play a role in the regulation of the HPA axis and partially mediate leptin-induced HPA stimulation. Copyright © 2006 by The Endocrine Society

    Analysis, Prevalence & Impact of Microplastics in Freshwater and Estuarine Environments Evidence Review 2 What are the sources of the microplastics found in freshwater environments?

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    This Rapid Evidence Assessment used the systematic review procedure to assess the current evidence available on the sources of the microplastics found in freshwater and estuarine environments. To fully comprehend the prevalence of microplastics in freshwater and estuarine environments, it is important to understand which sources contribute to the microplastics present and the relative importance of those sources. Furthermore, we need to understand the influence of any physical and biologically-mediated processes that affect the concentrations, characteristics and profile of the microplastic particles present, so that their influence can be taken into account when interpreting the microplastics present in terms of contributing sources. A review was conducted of literature, including grey literature, which reported evidence of the sources of the microplastics found in freshwater and estuarine environments. The factors influencing the transport and modification of microplastics in freshwater and estuarine environments were also considered, noting in particular those that alter the profile of microplastics thus obscuring identification of sources. Publications released prior to April 2019 were included in this review. Evidence was acquired according to a predefined set of questions, compiled into a database containing full details of the source and its relevance to the project questions, and the evidence analysed, taking into account reporting biases in the literature, to produce a digestible summary of the evidence base available to answer the main project question and sub-questions, namely, What are the sources of microplastics reported to have been found in freshwater and estuarine environments? a) Are these primary (i.e. manufactured) or secondary (i.e. degradation products) microplastics? b) Within studies reporting the predominant types of microplastics found, is there a link identified to local land use or industry? c) How are microplastics transported and modified in the freshwater and estuarine environments? d) Are microplastics from different sources prevalent in different matrices of the aquatic environment (biota, water, or sediment)

    Assessing availability and greenhouse gas emissions of lignocellulosic biomass feedstock supply – case study for a catchment in England

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    © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.Feedstocks from lignocellulosic biomass (LCB) include crop residues and dedicated per¬ennial biomass crops. The latter are often considered superior in terms of climate change mitigation potential. Uncertainty remains over their availability as feedstocks for biomass provision and the net greenhouse gas emissions (GHG) during crop production. Our objective was to assess the optimal land allocation to wheat and Miscanthus in a specific case study located in England, to increase bio¬mass availability, improve the carbon balance (and reduce the consequent GHG emissions), and mini¬mally constrain grain production losses from wheat. Using soil and climate variables for a catchment in east England, biomass yields and direct nitrogen emissions were simulated with validated process-based models. A ‘Field to up-stream factory gate’ life-cycle assessment was conducted to estimate indirect management-related GHG emissions. Results show that feedstock supply from wheat straw can be supplemented beneficially with LCB from Miscanthus grown on selected low-quality soils. In our study, 8% of the less productive arable land area was dedicated to Miscanthus, increasing total LCB provision by about 150%, with a 52% reduction in GHG emission per ton LCB delivered and only a minor effect on wheat grain production (−3%). In conclusion, even without considering the likely carbon sequestration in impoverished soils, agriculture should embrace the opportunities to provide the bioeconomy with LCB from dedicated, perennial crops.Peer reviewe

    Bifidobacterium longum 1714 as a translational psychobiotic: modulation of stress, electrophysiology and neurocognition in healthy volunteers

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    The emerging concept of psychobiotics—live microorganisms with a potential mental health benefit—represents a novel approach for the management of stress-related conditions. The majority of studies have focused on animal models. Recent preclinical studies have identified the B. longum 1714 strain as a putative psychobiotic with an impact on stress-related behaviors, physiology and cognitive performance. Whether such preclinical effects could be translated to healthy human volunteers remains unknown. We tested whether psychobiotic consumption could affect the stress response, cognition and brain activity patterns. In a within-participants design, healthy volunteers (N=22) completed cognitive assessments, resting electroencephalography and were exposed to a socially evaluated cold pressor test at baseline, post-placebo and post-psychobiotic. Increases in cortisol output and subjective anxiety in response to the socially evaluated cold pressor test were attenuated. Furthermore, daily reported stress was reduced by psychobiotic consumption. We also observed subtle improvements in hippocampus-dependent visuospatial memory performance, as well as enhanced frontal midline electroencephalographic mobility following psychobiotic consumption. These subtle but clear benefits are in line with the predicted impact from preclinical screening platforms. Our results indicate that consumption of B. longum 1714 is associated with reduced stress and improved memory. Further studies are warranted to evaluate the benefits of this putative psychobiotic in relevant stress-related conditions and to unravel the mechanisms underlying such effects

    Altered cellular redox homeostasis and redox responses under standard oxygen cell culture conditions versus physioxia.

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    In vivo, mammalian cells reside in an environment of 0.5-10% O2 (depending on the tissue location within the body), whilst standard in vitro cell culture is carried out under room air. Little is known about the effects of this hyperoxic environment on treatment-induced oxidative stress, relative to a physiological oxygen environment. In the present study we investigated the effects of long-term culture under hyperoxia (air) on photodynamic treatment. Upon photodynamic irradiation, cells which had been cultured long-term under hyperoxia generated higher concentrations of mitochondrial reactive oxygen species, compared with cells in a physioxic (2% O2) environment. However, there was no significant difference in viability between hyperoxic and physioxic cells. The expression of genes encoding key redox homeostasis proteins and the activity of key antioxidant enzymes was significantly higher after the long-term culture of hyperoxic cells compared with physioxic cells. The induction of antioxidant genes and increased antioxidant enzyme activity appear to contribute to the development of a phenotype that is resistant to oxidative stress-induced cellular damage and death when using standard cell culture conditions. The results from experiments using selective inhibitors suggested that the thioredoxin antioxidant system contributes to this phenotype. To avoid artefactual results, in vitro cellular responses should be studied in mammalian cells that have been cultured under physioxia. This investigation provides new insights into the effects of physioxic cell culture on a model of a clinically relevant photodynamic treatment and the associated cellular pathways

    Whole-genome association analysis of treatment response in obsessive-compulsive disorder.

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    Up to 30% of patients with obsessive-compulsive disorder (OCD) exhibit an inadequate response to serotonin reuptake inhibitors (SRIs). To date, genetic predictors of OCD treatment response have not been systematically investigated using genome-wide association study (GWAS). To identify specific genetic variations potentially influencing SRI response, we conducted a GWAS study in 804 OCD patients with information on SRI response. SRI response was classified as 'response' (n=514) or 'non-response' (n=290), based on self-report. We used the more powerful Quasi-Likelihood Score Test (the MQLS test) to conduct a genome-wide association test correcting for relatedness, and then used an adjusted logistic model to evaluate the effect size of the variants in probands. The top single-nucleotide polymorphism (SNP) was rs17162912 (P=1.76 × 10(-8)), which is near the DISP1 gene on 1q41-q42, a microdeletion region implicated in neurological development. The other six SNPs showing suggestive evidence of association (P&lt;10(-5)) were rs9303380, rs12437601, rs16988159, rs7676822, rs1911877 and rs723815. Among them, two SNPs in strong linkage disequilibrium, rs7676822 and rs1911877, located near the PCDH10 gene, gave P-values of 2.86 × 10(-6) and 8.41 × 10(-6), respectively. The other 35 variations with signals of potential significance (P&lt;10(-4)) involve multiple genes expressed in the brain, including GRIN2B, PCDH10 and GPC6. Our enrichment analysis indicated suggestive roles of genes in the glutamatergic neurotransmission system (false discovery rate (FDR)=0.0097) and the serotonergic system (FDR=0.0213). Although the results presented may provide new insights into genetic mechanisms underlying treatment response in OCD, studies with larger sample sizes and detailed information on drug dosage and treatment duration are needed

    Survey of the needs of patients with spinal cord injury: impact and priority for improvement in hand function in tetraplegics\ud

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    Objective: To investigate the impact of upper extremity deficit in subjects with tetraplegia.\ud \ud Setting: The United Kingdom and The Netherlands.\ud \ud Study design: Survey among the members of the Dutch and UK Spinal Cord Injury (SCI) Associations.\ud \ud Main outcome parameter: Indication of expected improvement in quality of life (QOL) on a 5-point scale in relation to improvement in hand function and seven other SCI-related impairments.\ud \ud Results: In all, 565 subjects with tetraplegia returned the questionnaire (overall response of 42%). Results in the Dutch and the UK group were comparable. A total of 77% of the tetraplegics expected an important or very important improvement in QOL if their hand function improved. This is comparable to their expectations with regard to improvement in bladder and bowel function. All other items were scored lower.\ud \ud Conclusion: This is the first study in which the impact of upper extremity impairment has been assessed in a large sample of tetraplegic subjects and compared to other SCI-related impairments that have a major impact on the life of subjects with SCI. The present study indicates a high impact as well as a high priority for improvement in hand function in tetraplegics.\ud \u
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