1,242 research outputs found

    Disease variants in genomes of 44 centenarians

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    To identify previously reported disease mutations that are compatible with extraordinary longevity, we screened the coding regions of the genomes of 44 Ashkenazi Jewish centenarians. Individual genome sequences were generated with 30x coverage on the Illumina HiSeq 2000 and single-nucleotide variants were called with the genome analysis toolkit (GATK). We identified 130 coding variants that were annotated as pathogenic or likely pathogenic based on the ClinVar database and that are infrequent in the general population. These variants were previously reported to cause a wide range of degenerative, neoplastic, and cardiac diseases with autosomal dominant, autosomal recessive, and X-linked inheritance. Several of these variants are located in genes that harbor actionable incidental findings, according to the recommendations of the American College of Medical Genetics. In addition, we found risk variants for late-onset neurodegenerative diseases, such as the APOE epsilon4 allele that was even present in a homozygous state in one centenarian who did not develop Alzheimer\u27s disease. Our data demonstrate that the incidental finding of certain reported disease variants in an individual genome may not preclude an extraordinarily long life. When the observed variants are encountered in the context of clinical sequencing, it is thus important to exercise caution in justifying clinical decisions

    Through a Glass Darkly: Facial Wrinkles Affect our Processing of Emotion in the Elderly

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    The correct interpretation of emotional expressions is crucial for social life. However, emotions in old relative to young faces are recognized less well. One reason for this may be decreased signal clarity of older faces due to morphological changes, such as wrinkles and folds, obscuring facial displays of emotions. Across three experiments, the present research investigates how misattributions of emotions to elderly faces impair emotion discrimination. In a preliminary task, neutral expressions were perceived as more expressive in old than in young faces by human raters (Experiment 1A) and an automatic system for emotion recognition (Experiment 1B). Consequently, task difficulty was higher for old faces relative to young faces in a visual search task (Experiment 2). Specifically, participants detected old faces expressing negative emotions less accurately and slower among neutral faces of their peers than young faces among neutral faces of their peers. Thus, we argue that age-related changes in facial features are the most plausible explanation for the differences in emotion perception between young and old faces. These findings are of relevance for the social interchange with the elderly, especially when multiple older individuals are present

    Understanding students’ motivation towards proactive career behaviours through goal-setting theory and the job demands–resources model

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    The graduate labour market is highly competitive but little is known about why students vary in their development of employability. This study contributes to the literature by applying goal-setting theory and the job demands–resources model to investigate how motivational processes influence students’ proactive career behaviours. We tested four hypotheses using structural equation modelling and moderation/mediation analysis using a nested model approach; 432 undergraduates from 21 UK universities participated in this cross-sectional study. The results showed that students higher in mastery approach had greater perceived employability mediated by two proactive career behaviours (skill development and network building). Students’ career goal commitment was associated with all four proactive career behaviours (career planning, skill development, career consultation and network building). Students’ academic and employment workloads did not negatively impact their proactive career behaviours. University tutors and career services should therefore encourage students to set challenging career goals that reflect mastery approach

    Benzo-fused Tri[8]annulenes as Molecular Models of Cubic Graphite

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    Cyclotrimerization of 9,10‐dibromo‐9,10‐dihydrodibenzo[3,4:7,8]cycloocta[1,2‐l]phenanthrene with potassium tert‐butoxide in the presence of a transition‐metal catalyst afforded two polycyclic aromatic hydrocarbon stereoisomers consisting of three cyclooctatetraene (COT) moieties connected via a central benzene ring. Both isomeric tri[8]annulenes were obtained selectively through the choice of the catalyst: The α,α,α‐form (Ru catalyst) displayed a threefold symmetrywith the COT subunits forming the side walls of a (chiral) molecular cup. In the thermodynamically more stable α,α,β‐isomer (Pd catalyst), one of the three boat‐shaped COTs was flipped over and faced the opposite molecular hemisphere with respect to the central benzene ring as evidenced by crystal structure analysis. Both title compounds are small segments of “cubic graphite”, an elusive carbon allotrope

    Combinatorial synthesis of (YxGd1-x)Ba2Cu3Ox superconducting thin films

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    Environmentally friendly water-based YBa2Cu3Ox (YBCO) and GdBa2Cu3Ox (GdBCO) precursor solutions were synthesized to realize thin films by chemical solution deposition. Pure YBCO and GdBCO precursor solutions were used for ink plotting on SrTiO3 substrates and subsequent thermal treatment at the corresponding crystallization temperature. Phase formation of Gd123 requires a higher crystallization temperature of 840 °C compared to the Y123 phase. The critical temperature of YBCO films is about 92 K with a sharp transition into the superconducting state. Micro liter sized ink volumes of YBCO and GdBCO were successfully mixed for two-dimensional ink plotting of a (YxGd1-x)Ba2Cu3Ox film library. A homogeneous surface and no indication of a-axis growth were found in all mixed films

    Nodal dynamics, not degree distributions, determine the structural controllability of complex networks

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    Structural controllability has been proposed as an analytical framework for making predictions regarding the control of complex networks across myriad disciplines in the physical and life sciences (Liu et al., Nature:473(7346):167-173, 2011). Although the integration of control theory and network analysis is important, we argue that the application of the structural controllability framework to most if not all real-world networks leads to the conclusion that a single control input, applied to the power dominating set (PDS), is all that is needed for structural controllability. This result is consistent with the well-known fact that controllability and its dual observability are generic properties of systems. We argue that more important than issues of structural controllability are the questions of whether a system is almost uncontrollable, whether it is almost unobservable, and whether it possesses almost pole-zero cancellations.Comment: 1 Figures, 6 page

    Hyperadiponectinemia During Infliximab Induction Therapy in Pediatric Crohn Disease

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    Objectives: The inflammatory process in Crohn disease (CD) involves the visceral fat, characterized by adipocyte hyperplasia and altered adipose tissue and serum concentrations of tumor necrosis factor (TNF), leptin, adiponectin and resistin. We investigated the effect of anti-TNF therapy with infliximab (IFX) on serum adipokine levels in pediatric CD. Methods: Serum concentrations of resistin (ng/mL), leptin (ng/mL), and total adiponectin (mu g/mL) were assessed by enzyme-linked immunosorbent assays (ELISA) in 18 pediatric CD patients (mean age 15.0 +/- 1.5 years) before first, second, and fourth IFX infusion (weeks 0, 2, and 14) and compared with baseline values from sex- and BMI-matched healthy controls (HC, mean age 13.4 +/- 1.6 years). Results: At baseline, CD patients (mean age 15.0 +/- 1.5 years, 10 of 18 boys) compared with HC (13.4 +/- 1.6 years, 7 of 15 boys) had higher resistin levels (median 14.7 ng/mL, range 5.1-50.5 vs 7.3 ng/mL, 0.5-14.5);P = 0.0002). At weeks 2 and 14, resistin decreased to 6.9 ng/mL (2.9-16.8) (P < 0.0001) and 9.2 ng/mL (4.1-20.6;P = 0.0011), respectively. Leptin and adiponectin were comparable between patients and HC at baseline. Leptin increased in girls from 9.5 ng/mL (4.0-30.1) to 16.0 ng/mL (7.9-35.2;P = 0.0156) and 17.2 ng/mL (10.8-26.8;P = 0.1953) at weeks 0, 2, and 14 respectively;with a trend in boys from 2 (0.6-12.9) to 2.8 (1.7-8.6;P = 0.0840) and 3.3 (1.34.6;P = 0.1309). Adiponectin peaked initially from 7.8 mu g/mL (4.6-11.9) at week 0 to 9.2 mu g/mL (4.1-20.7;P = 0.0005) at week 2 and thereafter fell to 6.5 mu g/mL (3.0-12.7;P = 0.0182) at week 14. Conclusions: TNF blockade is associated with changes in circulating adipokines. The marked early increase of the potent anti-inflammatory adiponectin may contribute to the rapid response to IFX in CD

    F18 fluorodeoxyglucose uptake in progressive transformation of germinal centres

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    FDG-PET/CT is a widely established imaging modality for staging, restaging and monitoring therapy response in lymphoma patients. Progressive transformation of germinal centres (PTGC) is a benign condition presenting characteristically as asymptomatic lymphadenopathy. This paper presents a case of a 53-year-old man with a history of Hodgkin’s disease (HD) whose F18 FDG-PET/CT scan showed high uptake in left axillary lymph nodes (SUV 3.8). A subsequent, left axillary lymph node biopsy revealed PTGC. PTGC can present as a false positive finding on FDG-PET/CT in lymphoma patients and biopsy should be done in HD patients in clinical remission but have a positive FDG-PET/CT scan

    A Simple Method for Analyzing Exome Sequencing Data Shows Distinct Levels of Nonsynonymous Variation for Human Immune and Nervous System Genes

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    To measure the strength of natural selection that acts upon single nucleotide variants (SNVs) in a set of human genes, we calculate the ratio between nonsynonymous SNVs (nsSNVs) per nonsynonymous site and synonymous SNVs (sSNVs) per synonymous site. We transform this ratio with a respective factor f that corrects for the bias of synonymous sites towards transitions in the genetic code and different mutation rates for transitions and transversions. This method approximates the relative density of nsSNVs (rdnsv) in comparison with the neutral expectation as inferred from the density of sSNVs. Using SNVs from a diploid genome and 200 exomes, we apply our method to immune system genes (ISGs), nervous system genes (NSGs), randomly sampled genes (RSGs), and gene ontology annotated genes. The estimate of rdnsv in an individual exome is around 20% for NSGs and 30–40% for ISGs and RSGs. This smaller rdnsv of NSGs indicates overall stronger purifying selection. To quantify the relative shift of nsSNVs towards rare variants, we next fit a linear regression model to the estimates of rdnsv over different SNV allele frequency bins. The obtained regression models show a negative slope for NSGs, ISGs and RSGs, supporting an influence of purifying selection on the frequency spectrum of segregating nsSNVs. The y-intercept of the model predicts rdnsv for an allele frequency close to 0. This parameter can be interpreted as the proportion of nonsynonymous sites where mutations are tolerated to segregate with an allele frequency notably greater than 0 in the population, given the performed normalization of the observed nsSNV to sSNV ratio. A smaller y-intercept is displayed by NSGs, indicating more nonsynonymous sites under strong negative selection. This predicts more monogenically inherited or de-novo mutation diseases that affect the nervous system
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