Critical Mechanism (critical + mechanism)

Distribution by Scientific Domains


Selected Abstracts


Perceived Maternal Parenting Self-Efficacy (PMP S-E) tool: development and validation with mothers of hospitalized preterm neonates

JOURNAL OF ADVANCED NURSING, Issue 5 2007
Christopher R. Barnes
Abstract Title.,Perceived Maternal Parenting Self-Efficacy (PMP S-E) tool: development and validation with mothers of hospitalized preterm neonates Aim., This paper is a report of a study to develop and test the psychometric properties of the Perceived Maternal Parenting Self-Efficacy tool. Background., Mothers' perceptions of their ability to parent (maternal parenting self-efficacy) is a critical mechanism guiding their interactions with their preterm newborns. A robust measure is needed which can measure mothers' perceptions of their ability to understand and care for their hospitalized preterm neonates as well as being sensitive to the various levels and tasks in parenting. Methods., Using a mixed sampling methodology (convenience or randomized cluster control trial) 165 relatively healthy and hospitalized mother-preterm infant dyads were recruited in 2003,2005 from two intensive care neonatal units in the United Kingdom (UK). Mothers were recruited within the first 28 days after giving birth to a preterm baby. The Perceived Maternal Parenting Self-Efficacy tool, which is made up of 20 items representing four theorized subscales, was tested for reliability and validity. Results., Internal consistency reliability of the Perceived Maternal Parenting Self-Efficacy tool was 0·91, external/test-retest reliability was 0·96, P < 0·01. Divergent validity using the Maternal Self-Report Inventory was rs = 0·4, P < 0·05 and using the Maternal Postnatal Attachment Scale was rs = 0·31, P < 0·01. Conclusion., The Perceived Maternal Parenting Self-Efficacy tool is a psychometrically robust, reliable and valid measure of parenting self-efficacy in mothers of relatively healthy hospitalized preterm neonates. Although application outside the UK will require further cross-cultural validation, the tool has the potential to provide healthcare professionals with a reliable method of identifying mothers of preterm hospitalized babies who are in need of further support. [source]


BTG2 antagonizes Pin1 in response to mitogens and telomere disruption during replicative senescence

AGING CELL, Issue 5 2010
Keith Wheaton
Summary Cellular senescence limits the replicative capacity of normal cells and acts as an intrinsic barrier that protects against the development of cancer. Telomere shortening,induced replicative senescence is dependent on the ATM-p53-p21 pathway but additional genes likely contribute to senescence. Here, we show that the p53-responsive gene BTG2 plays an essential role in replicative senescence. Similar to p53 and p21 depletion, BTG2 depletion in human fibroblasts leads to an extension of cellular lifespan, and ectopic BTG2 induces senescence independently of p53. The anti-proliferative function of BTG2 during senescence involves its stabilization in response to telomere dysfunction followed by serum-dependent binding and relocalization of the cell cycle regulator prolyl isomerase Pin1. Pin1 inhibition leads to senescence in late-passage cells, and ectopic Pin1 expression rescues cells from BTG2-induced senescence. The neutralization of Pin1 by BTG2 provides a critical mechanism to maintain senescent arrest in the presence of mitogenic signals in normal primary fibroblasts. [source]


Successful Six-Day Kidney Preservation Using Trophic Factor Supplemented Media and Simple Cold Storage

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2002
Jonathan F. McAnulty
This study examined the effect of trophic factor supplementation [TFS; bovine neutrophil peptide-1 (bactenecin), 1 mg/L; substance P, 2.5 mg/L; nerve growth factor, 20 ,g/L; epidermal growth factor, 10 ,g/L; insulin-like growth factor-1, 10 ,g/L] during cold storage with UW lactobionate solution. Dogs transplanted with kidneys stored for 4 days in TFS-UW had significantly lower peak serum creatinine values (mean 2.9 ± 0.2 mg/dL) and returned to normal values faster (6 days) than kidneys stored for 3 days in unmodified UW solution (4.2 ± 0.3 mg/dL and 14 days, respectively). Kidneys stored for 5 days in TFS-UW (mean peak creatinine 3.7 ± 0.3) functioned equivalently to kidneys stored for 3 days and better than kidneys stored for 4 days in UW alone. Dogs with kidneys stored for 6 days in TFS-UW had mean peak creatinines of 5.7 ± 0.4 mg/dL. These returned to normal creatinine values in 14 days, equal to 3-day stored and significantly better than kidneys stored for 4 days in UW alone (20 days recovery time). This study shows trophic factor deprivation appears to be a critical mechanism of injury in organ preservation with current synthetic storage media, and marks the initial development of a synthetic biologically active preservation solution, the next generation of preservation media. [source]


H. pylori selectively blocks EGFR endocytosis via the non-receptor kinase c-Abl and CagA

CELLULAR MICROBIOLOGY, Issue 1 2009
Bianca Bauer
Summary Helicobacter pylori infection is a primary cause of peptic ulcers and is associated with gastric carcinogenesis. The H. pylori -induced pathophysiology may be linked to the deregulation of EGFR signalling. Elevated mucosal levels of EGF and the EGFR have been found in antral gastric biopsies of H. pylori -infected patients. A critical mechanism for regulating EGFR signalling is ligand-induced endocytosis. The internalized receptor recycles back to the plasma membrane for continued signalling or is targeted for degradation terminating receptor signalling. Here, we show that H. pylori blocks EGFR endocytosis and receptor degradation upon prolonged infection of gastric epithelial cells. Moreover, this inhibition occurs via a CagA-dependent, but CagA phosphorylation-independent activation of the non-receptor kinase c-Abl, which in turn phosphorylates the EGFR target site pY1173. This suggests a novel CagA-induced host cell response that is independent of CagA tyrosine phosphorylation. Our data indicate an intriguing strategy of H. pylori in host cell manipulations by altering selective receptor populations via a CagA-dependent endocytic mechanism. Furthermore, we identified a new role for c-Abl in phosphorylation of the EGFR target site pY1173 during H. pylori infection. [source]


New genomic avenues in behavioural neuroendocrinology ,

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2002
S. L. Lightman
Abstract Neuroendocrine systems play a key role not only in the maintenance of whole-body homeostasis but also as the link between behavioural, endocrine and autonomic responses to environmental stimuli. It is becoming increasingly clear that neuroendocrine regulatory mechanisms are under the control of a combination of factors including genetic background, environment and early-life programming. Patterns of gene expression are increasingly being used to provide information on the genotypes associated with particular behaviours, and modulation of specific parts of the genome allow investigation of the contribution of particular genes. The sequencing of the genome provides a unique opportunity to elucidate the genetic contribution to neuroendocrine and behavioural processes, and to investigate the interactions between genetic and environmental factors. Although drugs can be used to activate or inhibit neurotransmitters and receptors, they lack specificity. New technologies now permit the activation or inactivation of both neurotransmitters and receptors in specific areas of the brain for defined periods, including crucially important developmental windows when activation appears to have long-term consequences. The future challenges are to define the critical mechanisms through which the genetic constitution of an individual human or experimental animal interacts with environmental cues to result in altered physiological or even pathological behaviour and endocrine function. [source]


Strategic planning for municipalities: Ensuring progress and relevance

PERFORMANCE IMPROVEMENT, Issue 5 2009
Thomas Plant
This article focuses on developing critical mechanisms to ensure the progress and relevance of a strategic plan. These mechanisms include the establishment of business planning processes, performance management and measurement, and reporting of strategic success. Although the focus here is on the public sector, these ideas can also be applied to and have relevance for strategic planning in any organizational context. [source]