38 research outputs found
The PDZ Protein Canoe/AF-6 Links Ras-MAPK, Notch and Wingless/Wnt Signaling Pathways by Directly Interacting with Ras, Notch and Dishevelled
Over the past few years, it has become increasingly apparent that signal transduction pathways are not merely linear cascades; they are organized into complex signaling networks that require high levels of regulation to generate precise and unique cell responses. However, the underlying regulatory mechanisms by which signaling pathways cross-communicate remain poorly understood. Here we show that the Ras-binding protein Canoe (Cno)/AF-6, a PDZ protein normally associated with cellular junctions, is a key modulator of Wingless (Wg)/Wnt, Ras-Mitogen Activated Protein Kinase (MAPK) and Notch (N) signaling pathways cross-communication. Our data show a repressive effect of Cno/AF-6 on these three signaling pathways through physical interactions with Ras, N and the cytoplasmic protein Dishevelled (Dsh), a key Wg effector. We propose a model in which Cno, through those interactions, actively coordinates, at the membrane level, Ras-MAPK, N and Wg signaling pathways during progenitor specification
A qualitative study of the understanding and use of ‘compassion focused coping strategies’ in people who suffer from serious weight difficulties.
Abstract Background The physical and psychological health problems associated with obesity are now well documented, as is the urgency for addressing them. In addition, associations between quality of life, depression, self-esteem, self-criticism, and obesity are now established indicating a need for a better understanding of the links between self-evaluation, affect-regulation and eating behaviours. Methods Compassion has now been identified as a major source of resilience, helpful self-relating and affect regulation. Thus this study used semi-structured interviews to explore the understanding and experiences of compassion in 2 overweight men and 10 women seeking help for weight problems. The interviews examined people's understandings of compassion, their recall of experiences of compassion in childhood, their current experiences of receiving compassion from others, being compassionate to others, being self-compassionate, and whether they would be compassionate or self-critical for relapses in overeating. Interviews were transcribed and analysed using thematic analysis (Qual Res Psychol, 3: 77-101, 2006). Results Participants saw compassion as related to ‘caring’ and being ‘listened to’. However, their recall of earlier experiences of compassion was of primarily practical help rather than emotional engagement. Typically their response to their own relapse and setbacks were self-criticism, self-disgust and even self-hatred rather than self-caring or understanding. Self-critical/hating responses tend to be associated with poor weight regulation. Conclusions When people with weight problems relapse, or struggle to control their eating, they can become quite self-critical, even self-hating, which may increase difficulties with emotionally coping and maintaining healthy lifestyles and eating habits. Although turning to others for support and compassion, and becoming self-compassionate are antidotes to self-criticism, and are associated with better coping and mental health, many participants did not utilise compassionate strategies – often the opposite. It is possible that interventions that include mindfulness and compassion training could be helpful for these difficulties.N/
Trace analysis of environmental matrices by large-volume injection and liquid chromatography-mass spectrometry
The time-honored convention of concentrating aqueous samples by solid-phase extraction (SPE) is being challenged by the increasingly widespread use of large-volume injection (LVI) liquid chromatography–mass spectrometry (LC–MS) for the determination of traces of polar organic contaminants in environmental samples. Although different LVI approaches have been proposed over the last 40 years, the simplest and most popular way of performing LVI is known as single-column LVI (SC-LVI), in which a large-volume of an aqueous sample is directly injected into an analytical column. For the purposes of this critical review, LVI is defined as an injected sample volume that is ≥10% of the void volume of the analytical column. Compared with other techniques, SC-LVI is easier to set up, because it requires only small hardware modifications to existing autosamplers and, thus, it will be the main focus of this review. Although not new, SC-LVI is gaining acceptance and the approach is emerging as a technique that will render SPE nearly obsolete for many environmental applications.In this review, we discuss: the history and development of various forms of LVI; the critical factors that must be considered when creating and optimizing SC-LVI methods; and typical applications that demonstrate the range of environmental matrices to which LVI is applicable, for example drinking water, groundwater, and surface water including seawater and wastewater. Furthermore, we indicate direction and areas that must be addressed to fully delineate the limits of SC-LVI
Pub1p C-Terminal RRM Domain Interacts with Tif4631p through a Conserved Region Neighbouring the Pab1p Binding Site
Pub1p, a highly abundant poly(A)+ mRNA binding protein in Saccharomyces cerevisiae, influences the stability and translational control of many cellular transcripts, particularly under some types of environmental stresses. We have studied the structure, RNA and protein recognition modes of different Pub1p constructs by NMR spectroscopy. The structure of the C-terminal RRM domain (RRM3) shows a non-canonical N-terminal helix that packs against the canonical RRM fold in an original fashion. This structural trait is conserved in Pub1p metazoan homologues, the TIA-1 family, defining a new class of RRM-type domains that we propose to name TRRM (TIA-1 C-terminal domain-like RRM). Pub1p TRRM and the N-terminal RRM1-RRM2 tandem bind RNA with high selectivity for U-rich sequences, with TRRM showing additional preference for UA-rich ones. RNA-mediated chemical shift changes map to β-sheet and protein loops in the three RRMs. Additionally, NMR titration and biochemical in vitro cross-linking experiments determined that Pub1p TRRM interacts specifically with the N-terminal region (1–402) of yeast eIF4G1 (Tif4631p), very likely through the conserved Box1, a short sequence motif neighbouring the Pab1p binding site in Tif4631p. The interaction involves conserved residues of Pub1p TRRM, which define a protein interface that mirrors the Pab1p-Tif4631p binding mode. Neither protein nor RNA recognition involves the novel N-terminal helix, whose functional role remains unclear. By integrating these new results with the current knowledge about Pub1p, we proposed different mechanisms of Pub1p recruitment to the mRNPs and Pub1p-mediated mRNA stabilization in which the Pub1p/Tif4631p interaction would play an important role
Improving nutritional care quality in the orthopedic ward of a Septic Surgery Center by implementing a preventive nutritional policy using the Nutritional Risk Score: a pilot study.
Septic Surgery Center (SSC) patients are at a particularly high risk of protein-energy malnutrition (PEM), with a prevalence of 35-85% found in various studies. Previous collaboration between our hospital's SSC and its Clinical Nutrition Team (CNT) only focussed on patients with severe PEM. This study aimed to determine whether it was possible to improve the quality of nutritional care in septic surgery patients with help of a nutritional policy using the Nutritional Risk Score (NRS).
Nutritional practices in the SSC were observed over three separate periods: in the 3 months leading up to the implementation baseline, 6 months after implementation of preventive nutritional practices, and at 3 years. The nutritional care quality indicator was the percentage of patients whose nutritional care, as prescribed by the SSC, was adapted to their specific requirements. We determined the septic surgery team's NRS completion rate and calculated the nutritional policy's impact on SSC length of stay. Data before (T <sub>0</sub> ) and after (T <sub>1</sub> + T <sub>2</sub> ) implementation of the nutritional policy were compared.
Ninety-eight patients were included. The nutritional care-quality indicator improved from 26 to 81% between T <sub>0</sub> and T <sub>2</sub> . During the T <sub>1</sub> and T <sub>2</sub> audits, septic surgery nurses calculated NRS for 100% and 97% of patients, respectively. Excluding patients with severe PEM, SSC length of stay was significantly reduced by 23 days (p = 0.005).
These findings showed that implementing a nutritional policy in an SSC is possible with the help of an algorithm including an easy-to-use tool like the NRS
Determination of sources and emissions of persistent organic contaminants by means of sewage sludge: results from a monitoring network
The mRNA cap-binding protein eIF4E in post-transcriptional gene expression
Eukaryotic initiation factor 4E (eIF4E) has central roles in the control of several aspects of post-transcriptional gene expression and thereby affects developmental processes. It is also implicated in human diseases. This review explores the relationship between structural, biochemical and biophysical aspects of eIF4E and its function in vivo, including both long-established roles in translation and newly emerging ones in nuclear export and mRNA decay pathways