158 research outputs found

    Poly[di-Ό-glycinato-copper(II)]: a two-dimensional coordination polymer

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    The title coordination polymer, [Cu(C2H4NO2)2]n, is two-dimensional and consists of a distorted octa­hedral copper coordination polyhedron with two bidentate glycine ligands chelating the metal through the O and N atoms in a trans-square-planar configuration. The two axial coordination sites are occupied by carbonyl O atoms of neighbouring glycine mol­ecules. The Cu—O distances for the axial O atoms [2.648 (2) and 2.837 (2) Å] are considerably longer than both the Cu—O [1.9475 (17) and 1.9483 (18) Å] and Cu—N [1.988 (2) and 1.948 (2) Å] distances in the equatorial plane, which indicates a strong Jahn–Teller effect. In the crystal, the two-dimensional networks are arranged parallel to (001) and are linked via N—H⋯O hydrogen bonds, forming a three-dimensional arrangement

    A Structural Diversity of Molecular Alkaline‐Earth‐Metal Polyphosphides: From Supramolecular Wheel to Zintl Ion

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    A series of molecular group 2 polyphosphides has been synthesized by using air‐stable [Cp*Fe(η(5)‐P(5))] (Cp*=C(5)Me(5)) or white phosphorus as polyphosphorus precursors. Different types of group 2 reagents such as organo‐magnesium, mono‐valent magnesium, and molecular calcium hydride complexes have been investigated to activate these polyphosphorus sources. The organo‐magnesium complex [((Dipp)BDI−Mg(CH(3)))(2)] ((Dipp)BDI={[2,6‐( i )Pr(2)C(6)H(3)NCMe](2)CH}(−)) reacts with [Cp*Fe(η(5)‐P(5))] to give an unprecedented Mg/Fe‐supramolecular wheel. Kinetically controlled activation of [Cp*Fe(η(5)‐P(5))] by different mono‐valent magnesium complexes allowed the isolation of Mg‐coordinated formally mono‐ and di‐reduced products of [Cp*Fe(η(5)‐P(5))]. To obtain the first examples of molecular calcium‐polyphosphides, a molecular calcium hydride complex was used to reduce the aromatic cyclo‐P(5) ring of [Cp*Fe(η(5)‐P(5))]. The Ca‐Fe‐polyphosphide is also characterized by quantum chemical calculations and compared with the corresponding Mg complex. Moreover, a calcium coordinated Zintl ion (P(7))(3−) was obtained by molecular calcium hydride mediated P(4) reduction

    Depth-dependent abundance of Midas Cichlid fish ( Amphilophus spp: ) in two Nicaraguan crater lakes

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    The Midas Cichlid species complex (Amphilophus spp.) in Central America serves as a prominent model system to study sympatric speciation and parallel adaptive radiation, since small arrays of equivalent ecotype morphs have evolved independently in different crater lakes. While the taxonomy and evolutionary history of the different species are well resolved, little is known about basic ecological parameters of Midas Cichlid assemblages. Here, we use a line transect survey to investigate the depth-dependent abundance of Amphilophus spp. along the shores of two Nicaraguan crater lakes, Apoyo and XiloĂĄ. We find a considerable higher density of Midas cichlids in Lake XiloĂĄ as compared to Lake Apoyo, especially at the shallowest depth level. This might be due to the higher eutrophication level of Lake XiloĂĄ and associated differences in food availability, and/or the presence of a greater diversity of niches in that lake. In any case, convergent forms evolved despite noticeable differences in size, age, eutrophication level, and carrying capacity. Further, our data provide abundance and density estimates for Midas Cichlid fish, which serve as baseline for future surveys of these ecosystems and are also relevant to past and future modeling of ecological speciatio

    Sleep sharpens sensory stimulus coding in human visual cortex after fear conditioning

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    Efficient perceptual identification of emotionally-relevant stimuli requires optimized neural coding. Because sleep contributes to neural plasticity mechanisms, we asked whether the perceptual representation of emotionally-relevant stimuli within sensory cortices is modified after a period of sleep. We show combined effects of sleep and aversive conditioning on subsequent discrimination of face identity information, with parallel plasticity in the amygdala and visual cortex. After one night of sleep (but neither immediately nor after an equal waking interval), a fear-conditioned face was better detected when morphed with another identity. This behavioral change was accompanied by increased selectivity of the amygdala and face-responsive fusiform regions. Overnight neural changes can thus sharpen the representation of threat-related stimuli in cortical sensory areas, in order to improve detection in impoverished or ambiguous situations. These findings reveal an important role of sleep in shaping cortical selectivity to emotionally-relevant cues and thus promoting adaptive responses to new dangers. (C) 2014 Elsevier Inc. All rights reserved

    Sleep sharpens sensory stimulus coding in human visual cortex after fear conditioning

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    Efficient perceptual identification of emotionally-relevant stimuli requires optimized neural coding. Because sleep contributes to neural plasticity mechanisms, we asked whether the perceptual representation of emotionally-relevant stimuli within sensory cortices is modified after a period of sleep. We show combined effects of sleep and aversive conditioning on subsequent discrimination of face identity information, with parallel plasticity in the amygdala and visual cortex. After one night of sleep (but neither immediately nor after an equal waking interval), a fear-conditioned face was better detected when morphed with another identity. This behavioral change was accompanied by increased selectivity of the amygdala and face-responsive fusiform regions. Overnight neural changes can thus sharpen the representation of threat-related stimuli in cortical sensory areas, in order to improve detection in impoverished or ambiguous situations. These findings reveal an important role of sleep in shaping cortical selectivity to emotionally-relevant cues and thus promoting adaptive responses to new dangers

    A peripheral epigenetic signature of immune system genes is linked to neocortical thickness and memory

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    Increasing age is tightly linked to decreased thickness of the human neocortex. The biological mechanisms that mediate this effect are hitherto unknown. The DNA methylome, as part of the epigenome, contributes significantly to age-related phenotypic changes. Here, we identify an epigenetic signature that is associated with cortical thickness (P=3.86 × 10(-8)) and memory performance in 533 healthy young adults. The epigenetic effect on cortical thickness was replicated in a sample comprising 596 participants with major depressive disorder and healthy controls. The epigenetic signature mediates partially the effect of age on cortical thickness (P<0.001). A multilocus genetic score reflecting genetic variability of this signature is associated with memory performance (P=0.0003) in 3,346 young and elderly healthy adults. The genomic location of the contributing methylation sites points to the involvement of specific immune system genes. The decomposition of blood methylome-wide patterns bears considerable potential for the study of brain-related traits

    Characteristics and properties of nano-LiCoO2 synthesized by pre-organized single source precursors: Li-ion diffusivity, electrochemistry and biological assessment

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    Background: LiCoO2 is one of the most used cathode materials in Li-ion batteries. Its conventional synthesis requires high temperature (>800 degrees C) and long heating time (>24 h) to obtain the micronscale rhombohedral layered high-temperature phase of LiCoO2 ( HT-LCO). Nanoscale HT-LCO is of interest to improve the battery performance as the lithium (Li+) ion pathway is expected to be shorter in nanoparticles as compared to micron sized ones. Since batteries typically get recycled, the exposure to nanoparticles during this process needs to be evaluated. Results: Several new single source precursors containing lithium (Li+) and cobalt (Co2+) ions, based on alkoxides and aryloxides have been structurally characterized and were thermally transformed into nanoscale HT-LCO at 450 degrees C within few hours. The size of the nanoparticles depends on the precursor, determining the electrochemical performance. The Li-ion diffusion coefficients of our - LiCoO2 nanoparticles improved at least by a factor of 10 compared to commercial one, while showing good reversibility upon charging and discharging. The hazard of occupational exposure to nanoparticles during battery recycling was investigated with an in vitro multicellular lung model. Conclusions: Our heterobimetallic single source precursors allow to dramatically reduce the production temperature and time for HT-LCO. The obtained nanoparticles of LiCoO2 have faster kinetics for Li+ insertion/extraction compared to microparticles. Overall, nano-sized - LiCoO2 particles indicate a lower cytotoxic and (pro-)inflammogenic potential in vitro compared to their micron-sized counterparts. However, nanoparticles aggregate in air and behave partially like microparticles

    GPR54 (KISS1R) Transactivates EGFR to Promote Breast Cancer Cell Invasiveness

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    Kisspeptins (Kp), peptide products of the Kisspeptin-1 (KISS1) gene are endogenous ligands for a G protein-coupled receptor 54 (GPR54). Previous findings have shown that KISS1 acts as a metastasis suppressor in numerous cancers in humans. However, recent studies have demonstrated that an increase in KISS1 and GPR54 expression in human breast tumors correlates with higher tumor grade and metastatic potential. At present, whether or not Kp signaling promotes breast cancer cell invasiveness, required for metastasis and the underlying mechanisms, is unknown. We have found that kisspeptin-10 (Kp-10), the most potent Kp, stimulates the invasion of human breast cancer MDA-MB-231 and Hs578T cells using Matrigel-coated Transwell chamber assays and induces the formation of invasive stellate structures in three-dimensional invasion assays. Furthermore, Kp-10 stimulated an increase in matrix metalloprotease (MMP)-9 activity. We also found that Kp-10 induced the transactivation of epidermal growth factor receptor (EGFR). Knockdown of the GPCR scaffolding protein, ÎČ-arrestin 2, inhibited Kp-10-induced EGFR transactivation as well as Kp-10 induced invasion of breast cancer cells via modulation of MMP-9 secretion and activity. Finally, we found that the two receptors associate with each other under basal conditions, and FRET analysis revealed that GPR54 interacts directly with EGFR. The stability of the receptor complex formation was increased upon treatment of cells by Kp-10. Taken together, our findings suggest a novel mechanism by which Kp signaling via GPR54 stimulates breast cancer cell invasiveness

    AIMSurv: First pan-European harmonized surveillance of Aedes invasive mosquito species of relevance for human vector-borne diseases

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    Human and animal vector-borne diseases, particularly mosquito-borne diseases, are emerging or re-emerging worldwide. Six Aedes invasive mosquito (AIM) species were introduced to Europe since the 1970s: Aedes aegypti, Ae. albopictus, Ae. japonicus, Ae. koreicus, Ae. atropalpus and Ae. triseriatus. Here, we report the results of AIMSurv2020, the first pan-European surveillance effort for AIMs. Implemented by 42 volunteer teams from 24 countries. And presented in the form of a dataset named “AIMSurv Aedes Invasive Mosquito species harmonized surveillance in Europe. AIM-COST Action. Project ID: CA17108”. AIMSurv2020 harmonizes field surveillance methodologies for sampling different AIMs life stages, frequency and minimum length of sampling period, and data reporting. Data include minimum requirements for sample types and recommended requirements for those teams with more resources. Data are published as a Darwin Core archive in the Global Biodiversity Information Facility- Spain, comprising a core file with 19,130 records (EventID) and an occurrences file with 19,743 records (OccurrenceID). AIM species recorded in AIMSurv2020 were Ae. albopictus, Ae. japonicus and Ae. koreicus, as well as native mosquito species

    Home-based health promotion for older people with mild frailty: the HomeHealth intervention development and feasibility RCT.

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    BACKGROUND: Mild frailty or pre-frailty is common and yet is potentially reversible. Preventing progression to worsening frailty may benefit individuals and lower health/social care costs. However, we know little about effective approaches to preventing frailty progression. OBJECTIVES: (1) To develop an evidence- and theory-based home-based health promotion intervention for older people with mild frailty. (2) To assess feasibility, costs and acceptability of (i) the intervention and (ii) a full-scale clinical effectiveness and cost-effectiveness randomised controlled trial (RCT). DESIGN: Evidence reviews, qualitative studies, intervention development and a feasibility RCT with process evaluation. INTERVENTION DEVELOPMENT: Two systematic reviews (including systematic searches of 14 databases and registries, 1990-2016 and 1980-2014), a state-of-the-art review (from inception to 2015) and policy review identified effective components for our intervention. We collected data on health priorities and potential intervention components from semistructured interviews and focus groups with older people (aged 65-94 years) (n = 44), carers (n = 12) and health/social care professionals (n = 27). These data, and our evidence reviews, fed into development of the 'HomeHealth' intervention in collaboration with older people and multidisciplinary stakeholders. 'HomeHealth' comprised 3-6 sessions with a support worker trained in behaviour change techniques, communication skills, exercise, nutrition and mood. Participants addressed self-directed independence and well-being goals, supported through education, skills training, enabling individuals to overcome barriers, providing feedback, maximising motivation and promoting habit formation. FEASIBILITY RCT: Single-blind RCT, individually randomised to 'HomeHealth' or treatment as usual (TAU). SETTING: Community settings in London and Hertfordshire, UK. PARTICIPANTS: A total of 51 community-dwelling adults aged ≄ 65 years with mild frailty. MAIN OUTCOME MEASURES: Feasibility - recruitment, retention, acceptability and intervention costs. Clinical and health economic outcome data at 6 months included functioning, frailty status, well-being, psychological distress, quality of life, capability and NHS and societal service utilisation/costs. RESULTS: We successfully recruited to target, with good 6-month retention (94%). Trial procedures were acceptable with minimal missing data. Individual randomisation was feasible. The intervention was acceptable, with good fidelity and modest delivery costs (ÂŁ307 per patient). A total of 96% of participants identified at least one goal, which were mostly exercise related (73%). We found significantly better functioning (Barthel Index +1.68; p = 0.004), better grip strength (+6.48 kg; p = 0.02), reduced psychological distress (12-item General Health Questionnaire -3.92; p = 0.01) and increased capability-adjusted life-years [+0.017; 95% confidence interval (CI) 0.001 to 0.031] at 6 months in the intervention arm than the TAU arm, with no differences in other outcomes. NHS and carer support costs were variable but, overall, were lower in the intervention arm than the TAU arm. The main limitation was difficulty maintaining outcome assessor blinding. CONCLUSIONS: Evidence is lacking to inform frailty prevention service design, with no large-scale trials of multidomain interventions. From stakeholder/public perspectives, new frailty prevention services should be personalised and encompass multiple domains, particularly socialising and mobility, and can be delivered by trained non-specialists. Our multicomponent health promotion intervention was acceptable and delivered at modest cost. Our small study shows promise for improving clinical outcomes, including functioning and independence. A full-scale individually RCT is feasible. FUTURE WORK: A large, definitive RCT of the HomeHealth service is warranted. STUDY REGISTRATION: This study is registered as PROSPERO CRD42014010370 and Current Controlled Trials ISRCTN11986672. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 73. See the NIHR Journals Library website for further project information
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