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Find video protocols related to scientific articles indexed in Pubmed.
Resource loss, self-efficacy, and family support predict posttraumatic stress symptoms: a 3-year study of earthquake survivors.
Anxiety Stress Coping
PUBLISHED: 09-17-2014
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Background and Objectives: Social support and self-efficacy are regarded as coping resources that may facilitate readjustment after traumatic events. The 2009 Cinchona earthquake in Costa Rica serves as an example for such an event to study resources to prevent subsequent severity of posttraumatic stress symptoms. Design: At Time 1 (1-6 months after the earthquake in 2009), N = 200 survivors were interviewed, assessing resource loss, received family support, and posttraumatic stress response. At Time 2 in 2012, severity of posttraumatic stress symptoms and general self-efficacy beliefs were assessed. Methods: Regression analyses estimated the severity of posttraumatic stress symptoms accounted for by all variables. Moderator and mediator models were examined to understand the interplay of received family support and self-efficacy with posttraumatic stress symptoms. Results: Baseline posttraumatic stress symptoms and resource loss (T1) accounted for significant but small amounts of the variance in the severity of posttraumatic stress symptoms (T2). The main effects of self-efficacy (T2) and social support (T1) were negligible, but social support buffered resource loss, indicating that only less supported survivors were affected by resource loss. Self-efficacy at T2 moderated the support-stress relationship, indicating that low levels of self-efficacy could be compensated by higher levels of family support. Receiving family support at T1 enabled survivors to feel self-efficacious, underlining the enabling hypothesis. Conclusions: Receiving social support from relatives shortly after an earthquake was found to be an important coping resource, as it alleviated the association between resource loss and the severity of posttraumatic stress response, compensated for deficits of self-efficacy, and enabled self-efficacy, which was in turn associated with more adaptive adjustment 3 years after the earthquake.
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A Randomized Controlled Trial to Promote Volunteering in Older Adults.
Psychol Aging
PUBLISHED: 08-18-2014
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Volunteering is presumed to confer health benefits, but interventions to encourage older adults to volunteer are sparse. Therefore, a randomized controlled trial with 280 community-dwelling older German adults was conducted to test the effects of a theory-based social-cognitive intervention against a passive waiting-list control group and an active control intervention designed to motivate physical activity. Self-reports of weekly volunteering minutes were assessed at baseline (5 weeks before the intervention) as well as 2 and 6 weeks after the intervention. Participants in the treatment group increased their weekly volunteering minutes to a greater extent than participants in the control groups 6 weeks after the intervention. We conclude that a single, face-to-face group session can increase volunteering among older community-dwelling adults. However, the effects need some time to unfold because changes in volunteering were not apparent 2 weeks after the intervention. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
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Transient electrostatic interactions dominate the conformational equilibrium sampled by multidomain splicing factor U2AF65: a combined NMR and SAXS study.
J. Am. Chem. Soc.
PUBLISHED: 04-29-2014
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Multidomain proteins containing intrinsically disordered linkers exhibit large-scale dynamic modes that play key roles in a multitude of molecular recognition and signaling processes. Here, we determine the conformational space sampled by the multidomain splicing factor U2AF65 using complementary nuclear magnetic resonance spectroscopy and small-angle scattering data. Available degrees of conformational freedom are initially stochastically sampled and experimental data then used to delineate the potential energy landscape in terms of statistical probability. The spatial distribution of U2AF65 conformations is found to be highly anisotropic, comprising significantly populated interdomain contacts that appear to be electrostatic in origin. This hypothesis is supported by the reduction of signature PREs reporting on expected interfaces with increasing salt concentration. The described spatial distribution reveals the complete spectrum of the unbound forms of U2AF65 that coexist with the small percentage of a preformed RNA-bound domain arrangement required for polypyrimidine-tract recognition by conformational selection. More generally, the proposed approach to describing conformational equilibria of multidomain proteins can be further combined with other experimental data that are sensitive to domain dynamics.
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Positive Exercise Experience Facilitates Behavior Change via Self-Efficacy.
Health Educ Behav
PUBLISHED: 04-10-2014
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Purpose. Motivational processes can be set in motion when positive consequences of physical exercise are experienced. However, relationships between positive exercise experience and determinants of the motivational and the volitional phases of exercise change have attracted only sparse attention in research. Method. This research examines direct and indirect associations between positive experience and motivational as well as volitional self-efficacy, intention, action planning, and exercise in two distinct longitudinal samples. The first one originates from an online observational study in the general population with three measurement points in time (N = 350) and the second one from a clinical intervention study in a rehabilitation context with four measurement points (N = 275). Results. Structural equation modeling revealed the following: Positive experience is directly related with motivational self-efficacy as well as intentions in both samples. In the online sample only, positive experience is associated with volitional self-efficacy. In each sample, experience is indirectly associated with action planning via motivational self-efficacy and intentions. Moreover, action planning, in turn, predicts changes in physical exercise levels. Conclusions. Findings suggest a more prominent role of positive experience in the motivational than in the volitional phase of physical exercise change. Thus, this research contributes to the understanding of how positive experience is involved in the behavior change process.
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Sources of self-efficacy for physical activity.
Health Psychol
PUBLISHED: 04-07-2014
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The effects of self-efficacy beliefs on physical activity are well documented, but much less is known about the origins of self-efficacy beliefs. This article proposes scales to assess the sources of self-efficacy for physical activity aims and to comparatively test their predictive power for physical activity via self-efficacy over time to detect the principal sources of self-efficacy beliefs for physical activity.
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What do targeting positive views on ageing add to a physical activity intervention in older adults? Results from a randomised controlled trial.
Psychol Health
PUBLISHED: 03-31-2014
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Physical activity is a key factor for healthy ageing, yet many older people lead a sedentary lifestyle. Traditional physical activity interventions do not consider the specific needs and views of older adults. As views on ageing are known to be related to health behaviours, the current study evaluates the effectiveness of prompting positive views on ageing within a physical activity intervention.
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Phosphorylation releases constraints to domain motion in ERK2.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 02-03-2014
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Protein motions control enzyme catalysis through mechanisms that are incompletely understood. Here NMR (13)C relaxation dispersion experiments were used to monitor changes in side-chain motions that occur in response to activation by phosphorylation of the MAP kinase ERK2. NMR data for the methyl side chains on Ile, Leu, and Val residues showed changes in conformational exchange dynamics in the microsecond-to-millisecond time regime between the different activity states of ERK2. In inactive, unphosphorylated ERK2, localized conformational exchange was observed among methyl side chains, with little evidence for coupling between residues. Upon dual phosphorylation by MAP kinase kinase 1, the dynamics of assigned methyls in ERK2 were altered throughout the conserved kinase core, including many residues in the catalytic pocket. The majority of residues in active ERK2 fit to a single conformational exchange process, with kex ? 300 s(-1) (kAB ? 240 s(-1)/kBA ? 60 s(-1)) and pA/pB ? 20%/80%, suggesting global domain motions involving interconversion between two states. A mutant of ERK2, engineered to enhance conformational mobility at the hinge region linking the N- and C-terminal domains, also induced two-state conformational exchange throughout the kinase core, with exchange properties of kex ? 500 s(-1) (kAB ? 15 s(-1)/kBA ? 485 s(-1)) and pA/pB ? 97%/3%. Thus, phosphorylation and activation of ERK2 lead to a dramatic shift in conformational exchange dynamics, likely through release of constraints at the hinge.
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Next-generation heteronuclear decoupling for high-field biomolecular NMR spectroscopy.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 01-07-2014
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Ultra-high-field NMR spectroscopy requires an increased bandwidth for heteronuclear decoupling, especially in biomolecular NMR applications. Composite pulse decoupling cannot provide sufficient bandwidth at practical power levels, and adiabatic pulse decoupling with sufficient bandwidth is compromised by sideband artifacts. A novel low-power, broadband heteronuclear decoupling pulse is presented that generates minimal, ultra-low sidebands. The pulse was derived using optimal control theory and represents a new generation of decoupling pulses free from the constraints of periodic and cyclic sequences. In comparison to currently available state-of-the-art methods this novel pulse provides greatly improved decoupling performance that satisfies the demands of high-field biomolecular NMR spectroscopy.
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Multiple illness perceptions in older adults: Effects on physical functioning and medication adherence.
Psychol Health
PUBLISHED: 12-12-2013
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Objective: Previous research on illness perceptions has focused on single illnesses, but most adults over 65 suffer from multiple illnesses (multimorbidity). This study tests three competing operationalisations of multiple illness perceptions in predicting physical functioning and adherence: (1) main effects and interactions model; (2) peak model with effects of the most prominent illness perception; and (3) combined model with averaged illness perceptions over multiple illnesses. Design: Longitudinal study in N?=?215 individuals (65-86?years) with multimorbidity at two measurement points over six months. Participants filled in two Brief Illness Perception Questionnaires (B-IPQ) on their two most severe illnesses. Main outcome measures: Physical functioning, medication adherence. Results: Factor analyses suggest that the B-IPQ contains three dimensions; consequences, control and timeline. Multiple regression models fit the data best for (1) and (3). Timeline (??=?-.18) and control (??=?.21) predict adherence in (1); consequences (??=?.16) and control (??=?.20) in (3). Physical functioning was significantly predicted by interacting control beliefs in (1; ??=?.13), by peak consequences in (2; ??=?-.14) and by consequences (??=?-.15) in (3). Conclusions: Individuals with multimorbidity hold both distinct and combined perceptions about their illnesses. To understand individual responses to multimorbidity, perceptions about all illnesses and multimorbidity as entity should be examined.
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How do negative self-perceptions of aging become a self-fulfilling prophecy?
Psychol Aging
PUBLISHED: 10-14-2013
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Recent studies have provided considerable evidence on long-term effects of self-perceptions of aging (SPA) on indicators of successful aging such as health or life satisfaction. To date, little is known about the mechanisms underlying these effects. This study therefore examined whether negative SPA impair the use of self-regulation strategies that include selection, optimization, and compensation (SOC) in case of a serious health event and thus turn into self-fulfilling prophecies for health and life satisfaction. Based on a longitudinal nationwide study with 2 measurement points over a 6-month period in 309 older people (65+ years of age) with multiple illnesses, 2 major findings emerged: First, the occurrence of a serious health event predicted increased use of SOC strategies, which in turn predicted higher self-rated health and life satisfaction. Second, this effect was moderated by negative SPA, that is, in case of a serious health event, the perception that aging is associated with physical losses led to lower use of SOC strategies promoting a healthy lifestyle (B = -0.43, SE = 0.15, p < .01). These findings contribute to a better understanding of the underlying mechanisms of SPA on health by showing that negative SPA as associated with physical losses might impair health-related strategies that are important for maintaining a healthy lifestyle. Future intervention studies could attempt to challenge negative SPA to support effective strategy use in older adults with serious illnesses. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
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Health motives and health behaviour self-regulation in older adults.
J Behav Med
PUBLISHED: 03-09-2013
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Health motives are motivational dispositions towards health. They are implicitly inherent in most health behaviour theories, yet rarely studied. We examined the role of health motives in health behaviour self-regulation (physical activity), particularly in the mediation of intention effects on behaviour via planning in an at-risk population with high need for behaviour change, older adults with multiple illnesses. A longitudinal study with two measurement points over 6 months was conducted, assessing 309 community-dwelling adults with multiple illnesses aged 65 and older. Health motives were assessed by contrasting health ratings with all other domains on the Personal Life Investment Schedule. Data were analysed in a moderated mediation framework using path analyses. Health Motives moderated the degree to which intentions predicted behaviour via planning (intention*health motives ? = .18, p < .05). Intentions are better translated into planning and behaviour if furnished with health motives. For older adults, this suggests that "health" in health behaviour change motivation merits more investigation, for example by stressing functional implications.
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Interactive effects of social support and social conflict on medication adherence in multimorbid older adults.
Soc Sci Med
PUBLISHED: 01-28-2013
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With increasing age and multimorbidity, medication regimens become demanding, potentially resulting in suboptimal adherence. Social support has been discussed as a predictor of adherence, but previous findings are inconsistent. The study examines general social support, medication-specific social support, and social conflict as predictors of adherence at two points in time (6 months apart) to test the mobilization and social conflict hypotheses. A total of 309 community-dwelling multimorbid adults (65-85 years, mean age 73.27, 41.7% women; most frequent illnesses: hypertension, osteoarthritis and hyperlipidemia) were recruited from the population-representative German Ageing Survey. Only medication-specific support correlated with adherence. Controlling for baseline adherence, demographics, physical fitness, medication regimen, and attitude, Time 1 medication-specific support negatively predicted Time 2 adherence, and vice versa. The negative relation between earlier medication-specific support and later adherence was not due to mobilization (low adherence mobilizing support from others, which over time would support adherence). Social conflict moderated the medication-specific support to adherence relationship: the relationship became more negative, the more social conflict participants reported. Presence of social conflict should be considered when received social support is studied, because well-intended help might have the opposite effect, when it coincides with social conflict.
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Partners in crime: the TGF? and MAPK pathways in cancer progression.
Cell Biosci
PUBLISHED: 11-10-2011
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The TGF? and Ras-MAPK pathways play critical roles in cell development and cell cycle regulation, as well as in tumor formation and metastasis. In the absence of cellular transformation, these pathways operate in opposition to one another, where TGF? maintains an undifferentiated cell state and suppresses proliferation, while Ras-MAPK pathways promote proliferation, survival and differentiation. However, in colorectal and pancreatic cancers, the opposing pathways mechanisms are simultaneously activated in order to promote cancer progression and metastasis. Here, we highlight the roles of the TGF? and Ras-MAPK pathways in normal and malignant states, and provide an explanation for how the concomitant activation of these pathways drives tumor biology. Finally, we survey potential therapeutic targets in these pathways.
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Self-efficacy and multiple illness representations in older adults: a multilevel approach.
Psychol Health
PUBLISHED: 07-07-2011
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The Common-Sense Model assumes that individuals form subjective representations about their illnesses, which in turn guide cognitive and behavioural responses. This assumption is complicated in individuals with multimorbidity, and it is an open question to which degree illness-specific and person-level factors determine the representations of specific illnesses. This study examines the structure and interrelations of illness representations in multimorbidity employing a hierarchical framework based on Cognitive Theory.
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Synergistic effect of social support and self-efficacy on physical exercise in older adults.
J Aging Phys Act
PUBLISHED: 07-06-2011
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The purpose of the current study was to examine whether the effects of social support on physical exercise in older adults depend on individual perceptions of self-efficacy. Three hundred nine older German adults (age 65-85) were assessed at 3 points in time (3 months apart). In hierarchical-regression analyses, support received from friends and exercise self-efficacy were specified as predictors of exercise frequency while baseline exercise, sex, age, and physical functioning were controlled for. Besides main effects of self-efficacy and social support, an interaction between social support and self-efficacy emerged. People with low self-efficacy were less likely to be active in spite of having social support. People with low support were less likely to be active even if they were high in self-efficacy. This points to the importance of both social support and self-efficacy and implies that these resources could be targets of interventions to increase older adults exercise.
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Health-specific optimism mediates between objective and perceived physical functioning in older adults.
J Behav Med
PUBLISHED: 06-22-2011
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Particularly in older adults, self-reports of physical health need not necessarily reflect their objective health status as they can be biased by optimism. In this study, we examine whether the effect of objective physical functioning on subjective physical functioning is modified by health-specific optimism and self-efficacy. A longitudinal study with three measurement points over 6 months and 309 older adults (aged 65-85) with multimorbidity was conducted. Subjective physical functioning was regressed on objective physical functioning, health-specific optimism and self-efficacy. Subjective physical functioning was predicted by both objective physical functioning and optimism as a mediator. Moreover, an interaction between optimism and self-efficacy was found: Optimism predicted subjective physical functioning only for individuals with low self-efficacy. Subjective physical functioning is as much based on objective physical functioning as it is on health-specific optimism. Older adults base their subjective physical functioning on objective indicators but also on optimism, when they are less self-efficacious.
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Structure of the BamC two-domain protein obtained by Rosetta with a limited NMR data set.
J. Mol. Biol.
PUBLISHED: 03-12-2011
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The CS-RDC-NOE Rosetta program was used to generate the solution structure of a 27-kDa fragment of the Escherichia coli BamC protein from a limited set of NMR data. The BamC protein is a component of the essential five-protein ?-barrel assembly machine in E. coli. The first 100 residues in BamC were disordered in solution. The Rosetta calculations showed that BamC??????? forms two well-defined domains connected by an ~18-residue linker, where the relative orientation of the domains was not defined. Both domains adopt a helix-grip fold previously observed in the Bet v 1 superfamily. ¹?N relaxation data indicated a high degree of conformational flexibility for the linker connecting the N-terminal domain and the C-terminal domain in BamC. The results here show that CS-RDC-NOE Rosetta is robust and has a high tolerance for misassigned nuclear Overhauser effect restraints, greatly simplifying NMR structure determinations.
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Changes in functional health, changes in medication beliefs, and medication adherence.
Health Psychol
PUBLISHED: 02-09-2011
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Medication adherence often lies below recommendations although it is crucial for effective therapies, particularly in older adults with multiple illnesses. Medication beliefs are important factors for individual adherence, but little is known about their origin. We examine whether changes in functional health predict changes in medication beliefs, and whether such changes in beliefs predict subsequent medication adherence.
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Genomic signatures of diet-related shifts during human origins.
Proc. Biol. Sci.
PUBLISHED: 12-22-2010
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There are numerous anthropological analyses concerning the importance of diet during human evolution. Diet is thought to have had a profound influence on the human phenotype, and dietary differences have been hypothesized to contribute to the dramatic morphological changes seen in modern humans as compared with non-human primates. Here, we attempt to integrate the results of new genomic studies within this well-developed anthropological context. We then review the current evidence for adaptation related to diet, both at the level of sequence changes and gene expression. Finally, we propose some ways in which new technologies can help identify specific genomic adaptations that have resulted in metabolic and morphological differences between humans and non-human primates.
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Structure and flexibility of the complete periplasmic domain of BamA: the protein insertion machine of the outer membrane.
Structure
PUBLISHED: 07-14-2010
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Folding and insertion of ?-barrel outer membrane proteins (OMPs) is essential for Gram-negative bacteria. This process is mediated by the multiprotein complex BAM, composed of the essential ?-barrel OMP BamA and four lipoproteins (BamBCDE). The periplasmic domain of BamA is key for its function and contains five "polypeptide transport-associated" (POTRA) repeats. Here, we report the crystal structure of the POTRA4-5 tandem, containing the essential for BAM complex formation and cell viability POTRA5. The domain orientation observed in the crystal is validated by solution NMR and SAXS. Using previously determined structures of BamA POTRA1-4, we present a spliced model of the entire BamA periplasmic domain validated by SAXS. Solution scattering shows that conformational flexibility between POTRA2 and 3 gives rise to compact and extended conformations. The length of BamA in its extended conformation suggests that the protein may bridge the inner and outer membranes across the periplasmic space.
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Giving and taking--differential effects of providing, receiving and anticipating emotional support on quality of life in adults with multiple illnesses.
J Health Psychol
PUBLISHED: 07-07-2010
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Multimorbidity challenges quality of life (QoL) in old age. Anticipating and providing social support have been shown to promote QoL whereas receiving support often had detrimental effects. Little is known about which psychological processes explain these effects. This study examines the effects of receiving, anticipating and providing emotional support on QoL, with control beliefs and self-esteem as simultaneous mediators in an elderly multimorbid sample (N = 1415). Anticipating and providing support positively predicted QoL, mediated through self-esteem and control beliefs. Received support negatively predicted QoL, without mediation. Self-esteem and control beliefs can help to explain the relation between QoL and support.
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A pipeline to determine RT-QPCR control genes for evolutionary studies: application to primate gene expression across multiple tissues.
PLoS ONE
PUBLISHED: 06-23-2010
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Because many species-specific phenotypic differences are assumed to be caused by differential regulation of gene expression, many recent investigations have focused on measuring transcript abundance. Despite the availability of high-throughput platforms, quantitative real-time polymerase chain reaction (RT-QPCR) is often the method of choice because of its low cost and wider dynamic range. However, the accuracy of this technique heavily relies on the use of multiple valid control genes for normalization. We created a pipeline for choosing genes potentially useful as RT-QPCR control genes for measuring expression between human and chimpanzee samples across multiple tissues, using published microarrays and a measure of tissue-specificity. We identified 13 genes from the pipeline and from commonly used control genes: ACTB, USP49, ARGHGEF2, GSK3A, TBP, SDHA, EIF2B2, GPDH, YWHAZ, HPTR1, RPL13A, HMBS, and EEF2. We then tested these candidate genes and validated their expression stability across species. We established the rank order of the most preferable set of genes for single and combined tissues. Our results suggest that for at least three tissues (cerebral cortex, liver, and skeletal muscle), EIF2B2, EEF2, HMBS, and SDHA are useful genes for normalizing human and chimpanzee expression using RT-QPCR. Interestingly, other commonly used control genes, including TBP, GAPDH, and, especially ACTB do not perform as well. This pipeline could be easily adapted to other species for which expression data exist, providing taxonomically appropriate control genes for comparisons of gene expression among species.
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Medication beliefs predict medication adherence in older adults with multiple illnesses.
J Psychosom Res
PUBLISHED: 03-17-2010
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To examine factors preventing medication nonadherence in community-dwelling older adults with multiple illnesses (multimorbidity). Nonadherence threatens successful treatment of multimorbidity. Adherence problems can be intentional (e.g., deliberately choosing not to take medicines or to change medication dosage) or unintentional (e.g., forgetting to take medication) and might depend on a range of factors. This study focused in particular on the role of changes in beliefs about medication to explain changes in adherence.
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Origin of Pax and Six gene families in sponges: Single PaxB and Six1/2 orthologs in Chalinula loosanoffi.
Dev. Biol.
PUBLISHED: 02-11-2010
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Pax genes play an important role in networks of transcription factors that determine organogenesis, notably the development of sensory organs. Other members of this regulatory network include transcription factors encoded by the Six gene family. Sponges lack organs and a nervous system, possibly because they have not evolved a Pax/Six network. Here we show that the demosponge Chalinula loosanoffi encodes only one Pax and one Six gene, representatives of the PaxB and Six1/2 subfamilies. Analysis of their temporal transcription patterns during development shows no correlation of their mRNA levels while their spatial patterns show some overlap of expression in adult tissue, although cellular resolution was not achieved. These results do not suggest that these genes form a major network in this basal phylum, although its existence in a minor fraction of cells is not excluded. We further show that sponge PaxB can substitute for some of the Pax2, but not of the Pax6 functions in Drosophila. Finally, we have analyzed the phylogeny of Pax and Six genes and have derived a model of the evolution of the Pax gene subfamilies in metazoans. It illustrates a diversification of Pax genes into subfamilies mostly in triploblasts before the protostome-deuterostome split, whereas few subfamilies were lost in various phyla after the Cambrian explosion.
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Comparative expression analysis of the phosphocreatine circuit in extant primates: Implications for human brain evolution.
J. Hum. Evol.
PUBLISHED: 02-06-2010
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While the hominid fossil record clearly shows that brain size has rapidly expanded over the last ~2.5 M.yr. the forces driving this change remain unclear. One popular hypothesis proposes that metabolic adaptations in response to dietary shifts supported greater encephalization in humans. An increase in meat consumption distinguishes the human diet from that of other great apes. Creatine, an essential metabolite for energy homeostasis in muscle and brain tissue, is abundant in meat and was likely ingested in higher quantities during human origins. Five phosphocreatine circuit proteins help regulate creatine utilization within energy demanding cells. We compared the expression of all five phosphocreatine circuit genes in cerebral cortex, cerebellum, and skeletal muscle tissue for humans, chimpanzees, and rhesus macaques. Strikingly, SLC6A8 and CKB transcript levels are higher in the human brain, which should increase energy availability and turnover compared to non-human primates. Combined with other well-documented differences between humans and non-human primates, this allocation of energy to the cerebral cortex and cerebellum may be important in supporting the increased metabolic demands of the human brain.
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Characterization of collagenous matrix assembly in a chondrocyte model system.
J Biomed Mater Res A
PUBLISHED: 09-01-2009
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Collagen is a major component of the newly synthesized pericellular microenvironment of chondrocytes. Collagen types II, IX, and XI are synthesized and assembled into higher ordered complexes by a mechanism in which type XI collagen plays a role in nucleation of new fibrils, and in limiting fibril diameter. This study utilizes a cell line derived from the Swarm rat chondrosarcoma that allows the accumulation and assembly of pericellular matrix. Immunofluorescence and atomic force microscopy were used to assess early intermediates of fibril formation. Results indicate that this cell line synthesizes and secretes chondrocyte-specific pericellular matrix molecules including types II, IX, and XI collagen and is suitable for the study of newly synthesized collagen matrix under the experimental conditions used. AFM data indicate that small fibrils or assemblies of microfibrils are detectable and may represent precursors of the approximately 20 nm thin fibrils reported in cartilage. Treatment with hyaluronidase indicates that the dimensions of the small fibrils may be dependent upon the presence of hyaluronan within the matrix. This study provides information on the composition and organization of the newly synthesized extracellular matrix that plays a role in establishing the material properties and performance of biological materials such as cartilage.
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Emotional and uncontrolled eating styles and chocolate chip cookie consumption. A controlled trial of the effects of positive mood enhancement.
Appetite
PUBLISHED: 07-09-2009
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The study tested the effects of positive mood enhancement on chocolate chip cookie consumption in the context of emotional and uncontrolled eating styles. The relationship between emotional eating style and chocolate chip cookie intake was assumed to be mediated by uncontrolled eating style. Further, it was hypothesized that the effectiveness of the positive mood enhancement may be more salient among those who have effective control of their eating. In this experimental study, respondents (N=106, 70% women, aged 16-45 years old) were assigned by means of cluster randomization to the control or positive mood enhancement condition (a comedy movie clip). Compared to the control condition, positive mood enhancement resulted in consuming on average 53.86 kcal less. Relationships between emotional eating style and cookie intake were mediated by uncontrolled eating. Moderated mediation analysis indicated that the effect of a mediator (uncontrolled eating) on cookie intake was moderated by the group assignment. Positive mood enhancement resulted in eating on average 3.3 cookies less among individuals with a more controlled eating style. By contrast, among those who presented uncontrolled eating, positive mood enhancement led to consuming an average of 1.7 cookies more.
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Functional consequences of genetic variation in primates on tyrosine hydroxylase (TH) expression in vitro.
Brain Res.
PUBLISHED: 03-18-2009
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Tyrosine hydroxylase, the rate-limiting enzyme in catecholamine synthesis, is known to contain naturally occurring genetic variation in its promoter region that associates with a number of neuropsychological disorders. As such, examining non-coding regions is important for understanding tyrosine hydroxylase function in human health and disease. We examined approximately 2 kb upstream of the translation start site within humans and non-human primates to obtain a fine resolution map of evolutionarily and functionally relevant cis-regulatory differences. Our study investigated Macaca mulatta, Pan troglodytes, Gorilla gorilla, and Homo sapiens haplotypes using transient dual-luciferase transfection in three neuroblastoma cell lines to assay the impact of naturally occurring sequence variation on expression level. In addition to trans effects between cell lines, there are several significant expression differences between primate species, but the most striking difference was seen between human haplotypes in one cell line. Underlying this variation are numerous sequence polymorphisms, two of which influence expression within humans in a non-additive and cell line-specific manner. This study highlights functional consequences of tyrosine hydroxylase genetic variation in primates. Additionally, the results emphasize the importance of examining more than one cell line, the existence of multiple functional variants in a given promoter region and the presence of non-additive cis-interactions.
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Contextual and individual predictors of physical activity: Interactions between environmental factors and health cognitions.
Health Psychol
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Although health behavior theories assume a role of the context in health behavior self-regulation, this role is often weakly specified and rarely examined. The two studies in this article test whether properties of the environment (districts) affect if and how health-related cognitions are translated into physical activity.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.