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151.
Meridith L. Eastman Brad Verhulst Lance M. Rappaport Melanie Dirks Chelsea Sawyers Daniel S. Pine Ellen Leibenluft Melissa A. Brotman John M. Hettema Roxann Roberson-Nay 《Behavior genetics》2018,48(6):421-431
The goal of the present investigation was to clarify and compare the structure of genetic and environmental influences on different types (e.g., physical, verbal) of peer victimization experienced by youth in pre-/early adolescence and mid-/late adolescence. Physical, verbal, social, and property-related peer victimization experiences were assessed in two twin samples (306 pairs, ages 9–14 and 294 pairs, ages 15–20). Cholesky decompositions of individual differences in victimization were conducted, and independent pathway (IP) and common pathway (CP) twin models were tested in each sample. In the younger sample, a Cholesky decomposition best described the structure of genetic and environmental contributors to peer victimization, with no evidence that common additive genetic or environmental factors influence different types of peer victimization. In the older sample, common environmental factors influenced peer victimization types via a general latent liability for peer victimization (i.e., a CP model). Whereas the pre-/early adolescent sample demonstrated no evidence of a shared genetic and environmental structure for different types of peer victimization, the mid-/late adolescent sample demonstrates the emergence of an environmentally-driven latent liability for peer victimization across peer victimization types. 相似文献
152.
BACKGROUND: Staphylococcus aureus bacteremia carries high mortality rates. The clinical impact of methicillin resistance remains controversial: outcome comparisons between patients with bacteremia involving methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) S aureus are difficult to perform because of important differences in severity of illness. METHODS: A retrospective cohort analysis and 2 independent case-control analyses were performed to determine and compare outcomes and attributable mortality rates of MSSA (n = 38) and MRSA bacteremia (n = 47) in critically ill patients. For the case-control studies, matching (1:2 ratio) was based on the APACHE (Acute Physiology and Chronic Health Evaluation) II classification: APACHE II score (+/-1 point) and diagnostic category. RESULTS: Patients with MRSA bacteremia had more acute renal failure and hemodynamic instability than patients with MSSA bacteremia. They had a longer intensive care unit stay and ventilator dependency. Patients with MRSA bacteremia had a higher 30-day mortality rate (53.2% vs 18.4%) and in-hospital mortality rate (63.8% vs 23.7%) (P<.05). Multivariate survival analysis demonstrated acute renal failure, length of mechanical ventilation, age, and methicillin resistance to be independently associated with mortality (P<.05). The attributable mortality rate for MSSA bacteremia was 1.3%: mortality rates for cases and controls were respectively 23.7% and 22.4% (P =.94). The attributable mortality rate for MRSA bacteremia was 23.4%: mortality rates for cases and controls were respectively 63.8% and 40.4% (P =.02). The difference (22.1%) between both attributable mortality rates was significant (95% confidence interval, 8.8%-35.3%). CONCLUSION: In critically ill patients, after accurate adjustment for disease severity and acute illness, we found MRSA bacteremia to have a higher attributable mortality than MSSA bacteremia. 相似文献
153.
Michael Karampelias Pia Neyt Steven De Groeve Stijn Aesaert Griet Coussens Jakub Rol?ík Leonardo Bruno Nancy De Winne Annemie Van Minnebruggen Marc Van Montagu María Rosa Ponce José Luis Micol Ji?í Friml Geert De Jaeger Mieke Van Lijsebettens 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(10):2768-2773
The shaping of organs in plants depends on the intercellular flow of the phytohormone auxin, of which the directional signaling is determined by the polar subcellular localization of PIN-FORMED (PIN) auxin transport proteins. Phosphorylation dynamics of PIN proteins are affected by the protein phosphatase 2A (PP2A) and the PINOID kinase, which act antagonistically to mediate their apical–basal polar delivery. Here, we identified the ROTUNDA3 (RON3) protein as a regulator of the PP2A phosphatase activity in Arabidopsis thaliana. The RON3 gene was map-based cloned starting from the ron3-1 leaf mutant and found to be a unique, plant-specific gene coding for a protein with high and dispersed proline content. The ron3-1 and ron3-2 mutant phenotypes [i.e., reduced apical dominance, primary root length, lateral root emergence, and growth; increased ectopic stages II, IV, and V lateral root primordia; decreased auxin maxima in indole-3-acetic acid (IAA)-treated root apical meristems; hypergravitropic root growth and response; increased IAA levels in shoot apices; and reduced auxin accumulation in root meristems] support a role for RON3 in auxin biology. The affinity-purified PP2A complex with RON3 as bait suggested that RON3 might act in PIN transporter trafficking. Indeed, pharmacological interference with vesicle trafficking processes revealed that single ron3-2 and double ron3-2 rcn1 mutants have altered PIN polarity and endocytosis in specific cells. Our data indicate that RON3 contributes to auxin-mediated development by playing a role in PIN recycling and polarity establishment through regulation of the PP2A complex activity.Organ growth is determined by cell numbers produced by meristems and by cell expansion to reach final volume. Plant hormones steer the extent and timing of growth and mediate signals of various types that are transmitted within the cell, between cells, or at a long distance within the plant. The phytohormone auxin is a major regulator of cell division and expansion during plant growth and development. The molecular mechanisms by which auxin controls these essential cellular responses are roughly understood thanks to the recent progress in the identification of auxin receptors and components of auxin signaling, transport, and metabolism (1). Auxin gradients between the cells are generated and maintained by intercellular auxin transport mediated by efflux carriers from the PIN-FORMED (PIN) family (2). PIN proteins contain transmembrane domains and continuously cycle between the basal (rootward) and apical (shootward) plasma membranes and endosomes, allowing rapid and dynamic changes in the PIN localization (3). The sorting of PIN proteins into the apical or basal trafficking pathway depends on the PIN phosphorylation status, which is controlled by the PINOID (PID) protein kinase and phosphatase 2A (PP2A) (4, 5), a heterotrimeric complex consisting of a C-catalytic subunit together with A- and B-regulatory subunits. One of the A-subunit isoforms, ROOTS CURL IN NAPHTHYLPHTHALAMIC ACID1 (RCN1), acts as a key positive regulator of the PP2A activity in seedlings. The rcn1 mutant that lost part of the PP2A activity displays abnormalities related to defective auxin transport, such as altered gravity response and lateral root growth (6, 7).In an ethyl methanesulfonate-induced collection of Arabidopsis thaliana leaf mutants (8), we identified ROTUNDA3 (RON3) as a proline-rich, plant-specific single-copy gene with a function in auxin-related processes in all organs throughout the plant’s lifecycle. Affinity purification of the PP2A complex with RON3 as bait, and genetic and cell biology analyses support the hypothesis that RON3 affects the cellular dynamics of PIN proteins through interference with the PP2A activity. 相似文献
154.
155.
Mónica López-Vicente Henning Tiemeier Andrea Wildeboer Ryan L. Muetzel Frank C. Verhulst Vincent W. V. Jaddoe 《Developmental neuropsychology》2017,42(2):58-69
ABSTRACTWe studied cortical morphology in relation to sports participation and type of sport using a large sample of healthy children (n = 911). Sports participation data was collected through a parent-reported questionnaire. Magnetic resonance scans were acquired, and different morphological brain features were quantified. Global volumetric measures were not associated with sports participation. We observed thicker cortex in motor and premotor areas associated with sports participation. In boys, team sports participation, relative to individual sports, was related to thinner cortex in prefrontal brain areas involved in the regulation of behaviors. This study showed a relationship between sports participation and brain maturation. 相似文献
156.
Prediction of behavioural and emotional problems in children and adolescents with operated congenital heart disease 总被引:4,自引:1,他引:4
Utens E.M.; Verhulst F.C.; Duivenvoorden H.J.; Meijboom F.J.; Erdman R.A.; Hess J. 《European heart journal》1998,19(5):801-807
Aims The aim of the present study was to determine which medicalvariables were predictors of long-term behavioural/emotionaloutcome after surgical correction for congenital heart diseasein infancy and childhood. Methods The Child Behavior Checklist (CBCL) was used to predict parent-reportedbehavioural/emotional problems in 125 1015 year-old congenitalheart disease children from: (1) biographical status (2) medicalhistory (3) heart surgery (4) short-term post-operative courseand (5) number of heart operations and (6) extra cardiac concomitantanomalies. Results Higher CBCL total problem scores at follow-up were associatedwith a greater number of heart oper-ations and deep hypothermiccirculatory arrest (<22°). Internalizing problemswere associated with a greater number of heart operations, deephypothermic circulatory arrest, a short gestational age, lowsystemic oxygen saturation, and older age at surgical repair.Externalizing problems were associated with agreater number of heart operations only. Conclusion Several medical variables were significant predictors and canbe used to identify those congenital heart disease childrenwho are at risk of long-term behavioural/emotional maladjustment. 相似文献
157.
Natasja A. M. Kragten Gina M. Doody Nicholas A. Barnes Ester B. M. Remmerswaal Cheng‐Chih Hsiao Perry D. Moerland Diana Wouters Ingrid A. M. Derks Amber van Stijn Marc Demkes Jörg Hamann Eric Eldering Martijn A. Nolte Reuben M. Tooze Ineke J. M. ten Berge René A. W. van Lier 《European journal of immunology》2015,45(10):2945-2958
158.
Since quite a few years, philosophy is heading towards the bedside of the patient: the practice of philosophy has stepped out of its ivory tower, it seems, to deal with empirical or practical questions. Apart from the advantages, we should keep in mind the importance of a critical analysis of medical or clinical practice as such. If ethics partakes the clinical stage, it runs the risk only to discuss the how question and to forget the more fundamental what or why questions: what are we doing exactly and why is it good for? Starting from the principle of the empowerment of the patient, we will demonstrate how the discourse on empowerment in health care seems to forget a profound reflection upon this principle as such. By rehearsing some basics from the governmentality theory of Michel Foucault and the actualization of it by Nicolas Rose, we will argue how philosophical investigation in medical‐ethical evolutions such as empowerment of the patient is still needed to understand what is really going on in today's clinical practice. 相似文献
159.
160.
Laura Q. Rogers Amanda Fogleman Steven Verhulst Mudita Bhugra Krishna Rao James Malone 《Journal of psychosocial oncology》2015,33(5):467-487
Social cognitive theory (SCT) measures related to exercise adherence in head and neck cancer (HNCa) patients were developed. Enrolling 101 HNCa patients, psychometric properties and associations with exercise behavior were examined for barriers self-efficacy, perceived barriers interference, outcome expectations, enjoyment, and goal setting. Cronbach's alpha ranged from.84 to.95; only enjoyment demonstrated limited test-retest reliability. Subscales for barriers self-efficacy (motivational, physical health) and barriers interference (motivational, physical health, time, environment) were identified. Multiple SCT constructs were cross-sectional correlates and prospective predictors of exercise behavior. These measures can improve the application of the SCT to exercise adherence in HNCa patients. 相似文献