63 research outputs found

    Behavioural and physiological consequences of acute social defeat in growing gilts: effects of the social environment

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    Endocrine, behavioural and immunologic processes, together with body growth, were evaluated in gilts that were defeated at 10 weeks of age in resident-intruder tests. Immediately after defeat, gilts were either separated from or reunited with a familiar conspecific (litter-mate; always a barrow). Gilts were assigned to one of four treatments: (a) DI: defeat, followed by isolation (separation from original litter-mate; n=8); (b) I: no defeat, isolation (control group; n=9); (c) DP; defeat, followed by pair-housing (reunion with original litter-mate; n=8); and (d) P: no defeat, pair-housing (control group; n=8). The following general conclusions were derived: (1) social defeat caused pronounced short-term elevations in hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal medullary activities, and of prolactin levels. Moreover, as soon as 1 h after defeat, percentages of blood lymphocytes and neutrophilic granulocytes were, respectively, decreased and increased; (2) social defeat had some long-lasting influence on behaviour and physiology, but isolation predominantly determined responses in the longer term. Defeat, as well as isolation, resulted in increased cardiovascular activities compared to P controls, as observed in a novel object test (NOT: +7 days) and an aversion test (AVT: +14 days). Moreover, defeated as well as isolated gilts did not habituate to a repeated novel environment test (NET: -7, +2 and +7 days) in terms of frequencies of vocalising, whereas P controls did. Isolation, through the separation from any other pig, was responsible for the other observed long-term characteristics, which developed progressively. Isolated gilts showed high mobilities and high cortisol responses in the repeated NET (+7 days), not being habituated. This contrasted the reactions of pair-housed gilts, which were much reduced. In addition to their high cardiovascular activities in the NOT and the AVT, isolated gilts also displayed higher heart rates in the repeated NET and during human presence following the NOT, compared to pair-housed gilts. Finally, isolated gilts were more inhibited to approach a novel object (in the NOT) than pair-housed pigs; and (3) stress responses of defeated gilts were modulated by the subsequent social environment. Stimulation of the HPA-axis (plasma- and salivary cortisol) was prolonged in those defeated gilts which were isolated (observed in the first hour). Changes in leucocyte subsets were still observed after 3 days in DI, but were `normalised' within 1 day in DP gilts. Two days after defeat, habituation to the repeated NET in terms of mobility and salivary cortisol responses occurred in control and DP gilts, but not in DI gilts. We argue that these effects of the social environment shortly after defeat were related to a stress-reducing effect of a stable social relationship, i.e. social support.

    De kost verdienen: de behoefte van voedsters aan ruwvoer

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    Om na te gaan of voedsters behoefte hebben aan ruwvoer is een kooi met keuzemogelijkheden ontwikkeld volgens het consumer-demand model. Begin dit jaar is men gestart met een eerste ronde, waarin voedsters konden kiezen tussen drie soorten ruwvoer. In dit artikel wordt ingegaan op dit onderzoe

    Internet-based self-help randomized trial for motor functional neurologic disorder (SHIFT).

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    OBJECTIVE: To determine whether self-rated health of patients with motor functional neurologic disorder (FND) can be improved by unguided Internet-based self-help and education. METHODS: In this nonblinded randomized controlled trial, patients were allocated 1:1 unbiased to an unguided education and self-help website in addition to usual care or usual care only. Patients over 17 years of age with a functional motor symptom that caused distress or disability were included. The primary outcome was self-rated health on the Clinical Global Improvement scale at 3 and 6 months. Secondary outcomes were severity of motor symptoms, other physical and psychiatric symptoms, physical functioning, quality of life, work and social adjustment, illness beliefs, and satisfaction with care. RESULTS: A total of 186 patients were randomized, with a follow-up rate of 87% at 6 months. There was no difference in improvement of self-rated health at 3 months (44% vs 40%, p = 0.899) or 6 months (42% vs 43%, p = 0.435). Secondary outcomes did not differ between groups, with a threshold of p < 0.01. Satisfaction was high, with 86% of patients recommending the website to other patients. CONCLUSION: We found no significant effect of the intervention added to usual care on self-rated health or secondary outcome measures, despite high patient satisfaction with the intervention. These results suggest that online education and nonguided self-help could be valuable additions to stepped care for motor FND, but are not effective treatments as interventions in their own right. CLINICALTRIALSGOV IDENTIFIER: NCT02589886. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for patients with motor FND, online education and self-help intervention does not significantly improve self-rated health

    Conformational changes during pore formation by the perforin-related protein pleurotolysin

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    Membrane attack complex/perforin-like (MACPF) proteins comprise the largest superfamily of pore-forming proteins, playing crucial roles in immunity and pathogenesis. Soluble monomers assemble into large transmembrane pores via conformational transitions that remain to be structurally and mechanistically characterised. Here we present an 11 Å resolution cryo-electron microscopy (cryo-EM) structure of the two-part, fungal toxin Pleurotolysin (Ply), together with crystal structures of both components (the lipid binding PlyA protein and the pore-forming MACPF component PlyB). These data reveal a 13-fold pore 80 Å in diameter and 100 Å in height, with each subunit comprised of a PlyB molecule atop a membrane bound dimer of PlyA. The resolution of the EM map, together with biophysical and computational experiments, allowed confident assignment of subdomains in a MACPF pore assembly. The major conformational changes in PlyB are a ~70° opening of the bent and distorted central β-sheet of the MACPF domain, accompanied by extrusion and refolding of two α-helical regions into transmembrane β-hairpins (TMH1 and TMH2). We determined the structures of three different disulphide bond-trapped prepore intermediates. Analysis of these data by molecular modelling and flexible fitting allows us to generate a potential trajectory of β-sheet unbending. The results suggest that MACPF conformational change is triggered through disruption of the interface between a conserved helix-turn-helix motif and the top of TMH2. Following their release we propose that the transmembrane regions assemble into β-hairpins via top down zippering of backbone hydrogen bonds to form the membrane-inserted β-barrel. The intermediate structures of the MACPF domain during refolding into the β-barrel pore establish a structural paradigm for the transition from soluble monomer to pore, which may be conserved across the whole superfamily. The TMH2 region is critical for the release of both TMH clusters, suggesting why this region is targeted by endogenous inhibitors of MACPF function

    Green Space and cognitive ageing: a retrospective life course analysis in the Lothian Birth Cohort 1936

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    International evidence suggests that green space has beneficial effects on general and mental health but little is known about how lifetime exposure to green space influences cognitive ageing. Employing a novel longitudinal life course approach, we examined the association between lifetime availability of public parks and cognitive ageing. Lifetime residential information was gathered from the participants of the Lothian Birth Cohort 1936 using a "life-grid" questionnaire at age 78 years. Parks information from 1949, 1969 and 2009 was used to determine a percentage of parks within a 1500 m buffer zone surrounding residence for childhood, adulthood, and later adulthood periods. Linear regressions were undertaken to test for association with age-standardised, residualised change in cognitive function (Moray House Test score) from age 11 to 70 years, and from age 70 to 76 (n = 281). The most appropriate model was selected using the results of a partial F-test, and then stratified by demographic, genetic and socioeconomic factors. The local provision of park space in childhood and adulthood were both important in explaining the change in cognitive function in later life. The association between childhood and adulthood park availability and change in the Moray House Test Score from age 70 to 76 was strongest for women, those without an APOE e4 allele (a genetic risk factor), and those in the lowest socioeconomic groups. Greater neighbourhood provision of public parks from childhood through to adulthood may help to slow down the rate of cognitive decline in later life, recognising that such environmental associations are always sensitive to individual characteristics

    Causes, consequences and biomarkers of stress in swine: an update

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    BACKGROUND: In recent decades there has been a growing concern about animal stress on intensive pig farms due to the undesirable consequences that stress produces in the normal physiology of pigs and its effects on their welfare and general productive performance. This review analyses the most important types of stress (social, environmental, metabolic, immunological and due to human handling), and their biological consequences for pigs. The physio-pathological changes associated with stress are described, as well as the negative effects of stress on pig production. In addition an update of the different biomarkers used for the evaluation of stress is provided. These biomarkers can be classified into four groups according to the physiological system or axis evaluated: sympathetic nervous system, hypothalamic-pituitary-adrenal axis, hypothalamic-pituitary-gonadal axis and immune system. CONCLUSIONS: Stress it is a process with multifactorial causes and produces an organic response that generates negative effects on animal health and production. Ideally, a panel of various biomarkers should be used to assess and evaluate the stress resulting from diverse causes and the different physiological systems involved in the stress response. We hope that this review will increase the understanding of the stress process, contribute to a better control and reduction of potential stressful stimuli in pigs and, finally, encourage future studies and developments to better monitor, detect and manage stress on pig farms

    CNS Damage Classification in Newborn Infants by Neural Network Based Cry Analysis

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    The central nervous system (CNS) of the human body is the whole system of brain, spinal marrow and nerve cells throughout the body that correlates and regulates the internal reactions of the body and controls its adjustment to the environment. It controls muscles and processes sensory information originating from visual, aural, and other sensorial systems. Apart from that, it constitutes important human properties such as the ability to learn, control, think, feel, have self-awareness et cetera. The central nervous system not only directs the body on a conscious level but also on a subconscious level, making sure that we keep breathing, for example. Considering all these functions, it is easy to understand that malfunctions of the central nervous system can easily result in very severe complications, ranging from diminished control over movements and actions to abrupt cessation of life. One of the possible ways for the central nervous system to become damaged is by a shortage of oxygen. Normally, oxygen is extracted from the air by the lungs, which have a huge surface that is rich with capillaries. This surface allows for diffusion of oxygen from the air into the blood. After this, the heart pumps the oxygen-rich blood through the body, where the oxygen is used for various purposes, including the function of the central nervous system. Hypoxia (or hypoxaemia) is the general phenomenon in which the oxygen level in the blood is too low for the body to perform normally. In hospitals, the oxygen level is usually monitored because it is a critical parameter in surgical anesthesia. Apart from the measurement tools available, hypoxia can often be diagnosed visually, because the subject's skin tends to turn bluish. In the case of newborns, however, this diagnosis is often more difficult. It is possible for the neonate to experience episodes of hypoxia before and during birth, in which case the hypoxic episode may very well go by unnoticed. When this happens, damage may have been inflicted to the central nervous system. This damage is often hard to recognize, as it may not show until a much later stage in the life of the newborn. In this paper we explore a neural network approach for classifying infant cry in order to detect hypoxia related CNS damage. The data set consists of 35 recorded cases of infant cries episodes, called the FCU data set. Each cry episode is split into valid cry units resulting in a data set of 183 elements, called the ACU data set. Relevant numerical features are determined by the research on features in the area of infant cry analysis and speech recognition. After determining the relevant features an ensemble of Radial Basis Neural Networks was constructed for both data sets (ACU and FCU) using bootstrap aggregation. Testing the classification performance resulted in a performance of 85 ±7 % (99 % confidence level) on the ACU data set and 76 ±19 % (99 % confidence level) on the FCU data set. These classification rates should be approached with caution, however. The 78% is the lower bound of the confidence interval for the results of the classification is based on a small data set. It should therefore be stressed that the results from this investigation are not to be taken any other than 'preliminary'. Much more data and testing needs to be done. In conclusion, the results that were found are encouraging in the sense that a statistically significant relationship was found. The feature selection and classification methods developed in this investigation can be a sound basis for continuation. Further research should divert its attention to the (frequency) measurement and noise issues and to the data availability issues KEYWORDS: infant cry analysis, neural networks, hypoxia-related CNS damag
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