1,219 research outputs found
Evaluation of participants' experiences with a non-restrictive minimally-structured lifestyle intervention. CHERE Working Paper 2010/11
While there is increasing evidence that group-based lifestyle-focussed interventions may provide more realistic, effective and cost-effective alternatives to intensive, individualised dietary counselling and exercise training, relatively little is known about individuals? preferences for and perceptions of these programs. This paper reports the results of qualitative interviews conducted with participants of a lifestyle intervention trial (Shape up for Life? (SufL) aimed to improve body composition and metabolic health through long-term non-restrictive behaviour modification. Purposive sampling was used to identify 22 participants who participated in detailed interviews regarding their expectations of the intervention, perceptions of benefits and their experience post-intervention and capacity to maintain the lifestyle changes. The results indicate that in general participants are focussed on weight loss as a goal, even when the intervention offered and provided other benefits such as improved fitness and body shape and composition. The individuals who benefited most from the intervention typically had lower baseline knowledge about dietary and exercise guidelines. While the relatively non-restrictive nature of SufL provided flexibility for participants, many participants perceived that a more structured program may have assisted in achieving weight loss goals.Obesity, lifestyle intervention, weight loss, metabolic syndrome
Exploring risk factors at the molecular level
Risk factors for cardiovascular diseases trigger molecular changes that harm the endothelial cells in the heart, but exercise can suppress these effects
Generation and physiological roles of linear ubiquitin chains
Ubiquitination now ranks with phosphorylation as one of the best-studied post-translational modifications of proteins with broad regulatory roles across all of biology. Ubiquitination usually involves the addition of ubiquitin chains to target protein molecules, and these may be of eight different types, seven of which involve the linkage of one of the seven internal lysine (K) residues in one ubiquitin molecule to the carboxy-terminal diglycine of the next. In the eighth, the so-called linear ubiquitin chains, the linkage is between the amino-terminal amino group of methionine on a ubiquitin that is conjugated with a target protein and the carboxy-terminal carboxy group of the incoming ubiquitin. Physiological roles are well established for K48-linked chains, which are essential for signaling proteasomal degradation of proteins, and for K63-linked chains, which play a part in recruitment of DNA repair enzymes, cell signaling and endocytosis. We focus here on linear ubiquitin chains, how they are assembled, and how three different avenues of research have indicated physiological roles for linear ubiquitination in innate and adaptive immunity and suppression of inflammation
Interactive Actor Analysis for Rural Water Management in The Netherlands
Recent developments in the policy sciences emphasize the social environment
in which decisions are made. The ‘network metaphor’ is often used to describe
the key role of interactions between interdependent actors involved in decision
making. These interactions take place in a policy arena drawn up by actors with an
interest in and control over decisions on the issues addressed. Interdependencies,
caused by the need for actors to increase their means of realizing objectives, are
the driving force behind these interactions. Dependency relations are of special
interest to water management and river basin management because of the fundamental
asymmetrical interdependencies that exist in river basins between upstream
and downstream stakeholders. Coleman’s linear system of action models decision
making process involving dependencies between multiple stakeholders as exchange
of control over issues, while interactions are required to negotiate exchanges of
control. We developed an interactive method for actor analysis based on Coleman’s
linear system of action and applied it to the national rural water management policy
domain in The Netherlands. The method is firmly rooted in mathematical sociology
and defies the criticism that methods for actor and stakeholder analysis do not specify
a theoretical basis explaining the causal relations between the variables analyzed and
policy change. With the application to the rural water management policy arena we
intended to increase our insight into the practical applicability of this analyticmethod
in an interactive workshop, the acceptability of the approach for the participating
actors, its contribution to the process of decision making and our understanding of
the rural water management policy arena in The Netherlands. We found that the
Association of Water Authorities, the Ministry of Public Works and the Ministry of
Agriculture are the most powerful actor in the policy domain, while governance and
cost and benefits of rural water management are the most salient issues. Progress
in policy development for rural water management is probably most promising for the issues governance, costs and benefits, safety and rural living conditions through
improved interaction between the Association of Water Authorities, the Ministry of
Agriculture and the Rural Credit Bank. Besides these analytic results the interactive
approach implemented increased the participants understanding of their dependency
on other actors in the rural water management policy domain and supported them
in developing a sound perspective on their dependency position. We concluded
that the method developed is acceptable to real-world policy decision makers, can
successfully be applied in an interactive setting, potentially contributes to the process
of decision making by increasing the participants understanding of their dependency
position, has the potential to delivers valuable advice for future decision-making and
increases our understanding of policy development for rural water management in
general
Spatio-temporal Models of Lymphangiogenesis in Wound Healing
Several studies suggest that one possible cause of impaired wound healing is
failed or insufficient lymphangiogenesis, that is the formation of new
lymphatic capillaries. Although many mathematical models have been developed to
describe the formation of blood capillaries (angiogenesis), very few have been
proposed for the regeneration of the lymphatic network. Lymphangiogenesis is a
markedly different process from angiogenesis, occurring at different times and
in response to different chemical stimuli. Two main hypotheses have been
proposed: 1) lymphatic capillaries sprout from existing interrupted ones at the
edge of the wound in analogy to the blood angiogenesis case; 2) lymphatic
endothelial cells first pool in the wound region following the lymph flow and
then, once sufficiently populated, start to form a network. Here we present two
PDE models describing lymphangiogenesis according to these two different
hypotheses. Further, we include the effect of advection due to interstitial
flow and lymph flow coming from open capillaries. The variables represent
different cell densities and growth factor concentrations, and where possible
the parameters are estimated from biological data. The models are then solved
numerically and the results are compared with the available biological
literature.Comment: 29 pages, 9 Figures, 6 Tables (39 figure files in total
Performance of the CMS Cathode Strip Chambers with Cosmic Rays
The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device
in the CMS endcaps. Their performance has been evaluated using data taken
during a cosmic ray run in fall 2008. Measured noise levels are low, with the
number of noisy channels well below 1%. Coordinate resolution was measured for
all types of chambers, and fall in the range 47 microns to 243 microns. The
efficiencies for local charged track triggers, for hit and for segments
reconstruction were measured, and are above 99%. The timing resolution per
layer is approximately 5 ns
Mouse Protocadherin-1 gene expression is regulated by cigarette smoke exposure in vivo
Protocadherin-1 (PCDH1) is a novel susceptibility gene for airway hyperresponsiveness, first identified in families exposed to cigarette smoke and is expressed in bronchial epithelial cells. Here, we asked how mouse Pcdh1 expression is regulated in lung structural cells in vivo under physiological conditions, and in both short-term cigarette smoke exposure models characterized by airway inflammation and hyperresponsiveness and chronic cigarette smoke exposure models. Pcdh1 gene-structure was investigated by Rapid Amplification of cDNA Ends. Pcdh1 mRNA and protein expression was investigated by qRT-PCR, western blotting using isoform-specific antibodies. We observed 87% conservation of the Pcdh1 nucleotide sequence, and 96% conservation of the Pcdh1 protein sequence between men and mice. We identified a novel Pcdh1 isoform encoding only the intracellular signalling motifs. Cigarette smoke exposure for 4 consecutive days markedly reduced Pcdh1 mRNA expression in lung tissue (3 to 4-fold), while neutrophilia and airway hyperresponsiveness was induced. Moreover, Pcdh1 mRNA expression in lung tissue was reduced already 6 hours after an acute cigarette-smoke exposure in mice. Chronic exposure to cigarette smoke induced loss of Pcdh1 protein in lung tissue after 2 months, while Pcdh1 protein levels were no longer reduced after 9 months of cigarette smoke exposure. We conclude that Pcdh1 is highly homologous to human PCDH1, encodes two transmembrane proteins and one intracellular protein, and is regulated by cigarette smoke exposure in vivo
The role of hybrid ubiquitin chains in the MyD88 and other innate immune signalling pathways
The adaptor protein MyD88 is required for signal transmission by Toll-like Receptors (TLRs) and receptors of the interleukin 1 (IL-1) family of cytokines. MyD88 signalling triggers the formation of Lys63-linked and Met1-linked ubiquitin (K63-Ub, M1-Ub) chains within minutes. The K63-Ub chains, which are formed by the E3 ubiquitin ligases TRAF6, Pellino1 and Pellino2, activate TAK1, the master kinase that switches on mitogen-activated protein (MAP) kinase cascades and initiates activation of the canonical IκB kinase (IKK) complex. The M1-Ub chains, which are formed by the Linear Ubiquitin chain Assembly Complex (LUBAC), bind to the NEMO component of the IKK complex and are required for TAK1 to activate IKKs, but not MAP kinases. An essential E3 ligase-independent role of TRAF6 is to recruit LUBAC into the MyD88 signalling complex, where it recognises preformed K63-Ub chains attached to protein components of these complexes, such as IRAK1, producing ubiquitin chains containing both types of linkage, termed K63/M1-Ub hybrids. The formation of K63/M1-Ub hybrids, which is a feature of several innate immune signalling pathways, permits the co-recruitment of proteins that interact with either K63-Ub or M1-Ub chains. Two likely roles for K63/M1- Ub hybrids are to facilitate the TAK1-dependent activation of the IKK complex and to prevent the hyper-activation of these kinases by recruiting A20 and A20-binding inhibitor of NF-κB1 (ABIN1). These proteins restrict activation of the TAK1 and IKK complexes, probably by competing with them for binding to K63/M1-Ub hybrids. The formation of K63/M1-Ub hybrids may also regulate the rate at which the ubiquitin linkages in these chains are hydrolysed. The IKK-catalysed phosphorylation of some of its substrates permits their recognition by the E3 ligase SCFβ TRCP, leading to their Lys48-linked ubiquitylation and proteasomal degradation. Innate immune signalling is therefore controlled by the formation and destruction of three different types of ubiquitin linkage
Evidence for acquisition of virulence effectors in pathogenic chytrids
Background
The decline in amphibian populations across the world is frequently linked to the infection of the chytrid fungus Batrachochytrium dendrobatidis (Bd). This is particularly perplexing because Bd was only recently discovered in 1999 and no chytrid fungus had previously been identified as a vertebrate pathogen.
Results
In this study, we show that two large families of known virulence effector genes, crinkler (CRN) proteins and serine peptidases, were acquired by Bd from oomycete pathogens and bacteria, respectively. These two families have been duplicated after their acquisition by Bd. Additional selection analyses indicate that both families evolved under strong positive selection, suggesting that they are involved in the adaptation of Bd to its hosts.
Conclusions
We propose that the acquisition of virulence effectors, in combination with habitat disruption and climate change, may have driven the Bd epidemics and the decline in amphibian populations. This finding provides a starting point for biochemical investigations of chytridiomycosis
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