19 research outputs found

    The Importance of Protein in Leaf Selection of Folivorous Primates

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    Protein limitation has been considered a key factor in hypotheses on the evolution of life history and animal communities, suggesting that animals should prioritize protein in their food choice. This contrasts with the limited support that food selection studies have provided for such a priority in nonhuman primates, particularly for folivores. Here, we suggest that this discrepancy can be resolved if folivores only need to select for high protein leaves when average protein concentration in the habitat is low. To test the prediction, we applied meta-analyses to analyze published and unpublished results of food selection for protein and fiber concentrations from 24 studies (some with multiple species) of folivorous primates. To counter potential methodological flaws, we differentiated between methods analyzing total nitrogen and soluble protein concentrations. We used a meta-analysis to test for the effect of protein on food selection by primates and found a significant effect of soluble protein concentrations, but a non-significant effect for total nitrogen. Furthermore, selection for soluble protein was reinforced in forests where protein was less available. Selection for low fiber content was significant but unrelated to the fiber concentrations in representative leaf samples of a given forest. There was no relationship (either negative or positive) between the concentration of protein and fiber in the food or in representative samples of leaves. Overall our study suggests that protein selection is influenced by the protein availability in the environment, explaining the sometimes contradictory results in previous studies on protein selectio

    Influence of Spiritual Dimensions on Suicide Risk: The Role of Regional Differences

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    The field of suicide prevention has been enriched by research on the association between spirituality and suicide. Many authors have suggested focusing on the various dimensions of religiosity in order to better understand the association between religion and suicidal risk, but it is unclear whether the relationship between spirituality and suicidality differs between countries with different cultures, life values, and sociohistorical experiences. To explore this, the aim of this multicenter study was to investigate the possible relationship between suicide and spirituality in Italy and Austria. In the two countries, two different groups of subjects participated: psychiatric patients and university students. The patients were evaluated with the Mini International Neuropsychiatric Interview. In addition, the following measures were used: a sociodemographic questionnaire, the Columbia-Suicide Severity Rating Scale-B, the Symptom-Checklist-90-Standard, and the Multidimensional Inventory for Religious/Spiritual Well-Being. Our results confirmed the multifactorial nature of the relation between suicide risk and the various religious/spiritual dimensions, including religious/spiritual well-being and hope immanent. However, regional differences moderated this relationship in both the clinical and nonclinical samples

    Suicide and Personality Traits: A Multicenter Study of Austrian and Italian Psychiatric Patients and Students

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    OBJECTIVE: The aim of this multicenter study was to investigate the differences in personality traits, particularly Neuroticism, in three clinical samples and three student samples in Austria and Italy and their impact on suicide. METHODS: In total, 1,043 people (410 psychiatric inpatients and 633 university students) were tested in three regions of Europe: central Italy, northeast Italy, and eastern Austria. Psychiatric diagnoses were evaluated using the Mini-International Neuropsychiatric Interview, and the following instruments were used: Sociodemographic Questionnaire, Columbia-Suicide Severity Rating Scale-B, Symptom-Checklist-90-Standard, and Big Five Inventory. RESULTS: The study found that the intensity of Suicidal Ideation was associated with the personality traits of Neuroticism, Anxiety, and Extraversion but also with Depression. CONCLUSIONS: In conclusion, without the presence of Depression symptoms, neuroticism was a protective factor against Suicidal Ideation, whereas neuroticism when comorbid with Depression symptoms increased suicide risk in psychiatric patients. In all three regions, the clinical samples had higher scores for Neuroticism and for Depression symptoms than the student sample and consequently higher scores for Suicide. Furthermore, we demonstrated an interaction between gender and culture on personality traits, supporting the hypothesis that the distribution of self-reported personality traits is organized geographically

    Elezanumab, a human anti-RGMa monoclonal antibody, promotes neuroprotection, neuroplasticity, and neurorecovery following a thoracic hemicompression spinal cord injury in non-human primates.

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    Spinal cord injury (SCI) is a devastating condition characterized by loss of function, secondary to damaged spinal neurons, disrupted axonal connections, and myelin loss. Spontaneous recovery is limited, and there are no approved pharmaceutical treatments to reduce ongoing damage or promote repair. Repulsive guidance molecule A (RGMa) is upregulated following injury to the central nervous system (CNS), where it is believed to induce neuronal apoptosis and inhibit axonal growth and remyelination. We evaluated elezanumab, a human anti-RGMa monoclonal antibody, in a novel, newly characterized non-human primate (NHP) hemicompression model of thoracic SCI. Systemic intravenous (IV) administration of elezanumab over 6 months was well tolerated and associated with significant improvements in locomotor function. Treatment of animals for 16 weeks with a continuous intrathecal infusion of elezanumab below the lesion was not efficacious. IV elezanumab improved microstructural integrity of extralesional tissue as reflected by higher fractional anisotropy and magnetization transfer ratios in treated vs. untreated animals. IV elezanumab also reduced SCI-induced increases in soluble RGMa in cerebrospinal fluid, and membrane bound RGMa rostral and caudal to the lesion. Anterograde tracing of the corticospinal tract (CST) from the contralesional motor cortex following 20 weeks of IV elezanumab revealed a significant increase in the density of CST fibers emerging from the ipsilesional CST into the medial/ventral gray matter. There was a significant sprouting of serotonergic (5-HT) fibers rostral to the injury and in the ventral horn of lower thoracic regions. These data demonstrate that 6 months of intermittent IV administration of elezanumab, beginning within 24 h after a thoracic SCI, promotes neuroprotection and neuroplasticity of key descending pathways involved in locomotion. These findings emphasize the mechanisms leading to improved recovery of neuromotor functions with elezanumab in acute SCI in NHPs

    A new vertebrate SUMO enzyme family reveals insights into SUMO-chain assembly

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    SUMO chains act as stress-induced degradation tags or repair factor-recruiting signals at DNA lesions. Although El activating, E2 conjugating and E3 ligating enzymes efficiently assemble SUMO chains, specific chain-elongation mechanisms are unknown. E4 elongases are specialized E3 ligases that extend a chain but are inefficient in the initial conjugation of the modifier. We identified ZNF451, a representative member of a new class of SUMO2 and SUM03 (SUMO2/3)-specific enzymes that execute catalysis via a tandem SUMO-interaction motif (SIM) region. One SIM positions the donor SUMO while a second SIM binds SUMO on the back side of the E2 enzyme. This tandem-SIM region is sufficient to extend a back side-anchored SUMO chain (E4 elongase activity), whereas efficient chain initiation also requires a zinc-finger region to recruit the initial acceptor SUMO (E3 ligase activity). Finally, we describe four human proteins sharing E4 elongase activities and their function in stress-induced SUMO2/3 conjugation
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