1,164 research outputs found
The structural invisibility of outsiders: the role of migrant labour in the meat-processing industry
This article examines the role of migrant workers in meat-processing factories in the UK. Drawing on materials from mixed methods research in a number of case study towns across Wales, we explore the structural and spatial processes that position migrant workers as outsiders. While state policy and immigration controls are often presented as a way of protecting migrant workers from work-based exploitation and ensuring jobs for British workers, our research highlights that the situation ‘on the ground’ is more complex. We argue that ‘self-exploitation’ among the migrant workforce is linked to the strategies of employers and the organisation of work, and that hyper-flexible work patterns have reinforced the spatial and social invisibilities of migrant workers in this sector. While this creates problems for migrant workers, we conclude that it is beneficial to supermarkets looking to supply consumers with the regular supply of cheap food to which they have become accustomed
Preoperative bowel stimulation prior to ileostomy closure to restore bowel function more quickly and improve postoperative outcomes: a systematic review
Aim
Closure of a diverting ileostomy following restorative surgery is often associated with significant short‐term morbidity and variable long‐term bowel function. The aim of this systematic review was to investigate if preoperative stimulation of the defunctioned bowel restores bowel function more quickly after ileostomy closure and improves postoperative outcomes when compared with standard preoperative care.
Method
MEDLINE, Embase, CENTRAL, Google Scholar and ClinicalTrials.gov were searched for studies evaluating preoperative bowel stimulation in patients with a temporary ileostomy after low anterior resection or ileal pouch–anal anastomosis, regardless of their design, publication type or language. Study selection, data extraction and study assessment were performed by one reviewer and verified by another. Study results were synthesized narratively. The GRADE approach was used to assess the quality of evidence.
Results
Eight studies involving a total of 267 participants were included. The studies had a moderate to high risk of bias and were of varying methodological quality. Preoperative stimulation of the defunctioned bowel reduced the time to postoperative restoration of bowel function and the length of hospital stay when compared with standard preoperative care. Other functional outcomes and postoperative complication rates were similar to those of standard preoperative care. The overall quality of evidence was very low.
Conclusion
Despite these promising early results, there is insufficient high‐quality evidence to recommend routine implementation of preoperative bowel stimulation in clinical practice. Nevertheless, there is no evidence suggesting that the intervention worsens outcomes or is unsafe, paving the way for rigorous assessment of effectiveness, acceptability and cost‐effectiveness within the context of well‐designed clinical trials
Site-specific perturbations of alpha-synuclein fibril structure by the Parkinson's disease associated mutations A53T and E46K.
PMCID: PMC3591419This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Parkinson's disease (PD) is pathologically characterized by the presence of Lewy bodies (LBs) in dopaminergic neurons of the substantia nigra. These intracellular inclusions are largely composed of misfolded α-synuclein (AS), a neuronal protein that is abundant in the vertebrate brain. Point mutations in AS are associated with rare, early-onset forms of PD, although aggregation of the wild-type (WT) protein is observed in the more common sporadic forms of the disease. Here, we employed multidimensional solid-state NMR experiments to assess A53T and E46K mutant fibrils, in comparison to our recent description of WT AS fibrils. We made de novo chemical shift assignments for the mutants, and used these chemical shifts to empirically determine secondary structures. We observe significant perturbations in secondary structure throughout the fibril core for the E46K fibril, while the A53T fibril exhibits more localized perturbations near the mutation site. Overall, these results demonstrate that the secondary structure of A53T has some small differences from the WT and the secondary structure of E46K has significant differences, which may alter the overall structural arrangement of the fibrils
Features of mammalian microRNA promoters emerge from polymerase II chromatin immunoprecipitation data
Background: MicroRNAs (miRNAs) are short, non-coding RNA regulators of protein coding genes. miRNAs play a very important role in diverse biological processes and various diseases. Many algorithms are able to predict miRNA genes and their targets, but their transcription regulation is still under investigation. It is generally believed that intragenic miRNAs (located in introns or exons of protein coding genes) are co-transcribed with their host genes and most intergenic miRNAs transcribed from their own RNA polymerase II (Pol II) promoter. However, the length of the primary transcripts and promoter organization is currently unknown. Methodology: We performed Pol II chromatin immunoprecipitation (ChIP)-chip using a custom array surrounding regions of known miRNA genes. To identify the true core transcription start sites of the miRNA genes we developed a new tool (CPPP). We showed that miRNA genes can be transcribed from promoters located several kilobases away and that their promoters share the same general features as those of protein coding genes. Finally, we found evidence that as many as 26% of the intragenic miRNAs may be transcribed from their own unique promoters. Conclusion: miRNA promoters have similar features to those of protein coding genes, but miRNA transcript organization is more complex. © 2009 Corcoran et al
Status of the LUX Dark Matter Search
The Large Underground Xenon (LUX) dark matter search experiment is currently
being deployed at the Homestake Laboratory in South Dakota. We will highlight
the main elements of design which make the experiment a very strong competitor
in the field of direct detection, as well as an easily scalable concept. We
will also present its potential reach for supersymmetric dark matter detection,
within various timeframes ranging from 1 year to 5 years or more.Comment: 4 pages, in proceedings of the SUSY09 conferenc
The ansamycin antibiotic, rifamycin SV, inhibits BCL6 transcriptional repression and forms a complex with the BCL6-BTB/POZ domain
BCL6 is a transcriptional repressor that is over-expressed due to chromosomal translocations, or other abnormalities, in ~40% of diffuse large B-cell lymphoma. BCL6 interacts with co-repressor, SMRT, and this is essential for its role in lymphomas. Peptide or small molecule inhibitors, which prevent the association of SMRT with BCL6, inhibit transcriptional repression and cause apoptosis of lymphoma cells in vitro and in vivo. In order to discover compounds, which have the potential to be developed into BCL6 inhibitors, we screened a natural product library. The ansamycin antibiotic, rifamycin SV, inhibited BCL6 transcriptional repression and NMR spectroscopy confirmed a direct interaction between rifamycin SV and BCL6. To further determine the characteristics of compounds binding to BCL6-POZ we analyzed four other members of this family and showed that rifabutin, bound most strongly. An X-ray crystal structure of the rifabutin-BCL6 complex revealed that rifabutin occupies a partly non-polar pocket making interactions with tyrosine58, asparagine21 and arginine24 of the BCL6-POZ domain. Importantly these residues are also important for the interaction of BLC6 with SMRT. This work demonstrates a unique approach to developing a structure activity relationship for a compound that will form the basis of a therapeutically useful BCL6 inhibitor
Why do women not use antenatal services in low and middle income countries? A metasynthesis of qualitative studies
Background:
Almost 50% of women in low & middle income countries (LMIC’s) don’t receive adequate antenatal care. Women’s views can offer important insights into this problem. Qualitative studies exploring inadequate use of antenatal services have been undertaken in a range of countries, but the findings are not easily transferable. We aimed to inform the development of future antenatal care programmes through a synthesis of findings in all relevant qualitative studies.
Methods and Findings:
Using a pre-determined search strategy, we identified robust qualitative studies reporting on the views and experiences of women in LMIC’s who received inadequate antenatal care. We used meta-ethnographic techniques to generate themes and a line of argument synthesis. We derived policy relevant hypotheses from the findings.
We included 21 papers representing the views of more than 1230 women from 15 countries. Three key themes were identified: ‘Pregnancy as socially risky and physiologically healthy’; ‘Resource use and survival in conditions of extreme poverty’and ‘Not getting it right first time’. The line of argument synthesis describes a dissonance between programme design and cultural contexts that may restrict access and discourage return visits. We hypothesize that centralized, risk-focused antenatal care programmes may be at odds with the resources, beliefs and experiences of pregnant women who underuse antenatal services.
Conclusions:
Our findings suggest that there may be a mis-alignment between current antenatal provision and the social and cultural context of some women in LMIC’s. Antenatal care provision that is theoretically and contextually at odds with local contextual beliefs and experiences are likely to be underused, especially when attendance generates increased personal risks of lost family resource or physical danger during travel; when the promised care is not delivered due to resource constraints; and when women experience covert or overt abuse in care settings
A Survey on Continuous Time Computations
We provide an overview of theories of continuous time computation. These
theories allow us to understand both the hardness of questions related to
continuous time dynamical systems and the computational power of continuous
time analog models. We survey the existing models, summarizing results, and
point to relevant references in the literature
Allorecognition in the Tasmanian Devil (Sarcophilus harrisii), an Endangered Marsupial Species with Limited Genetic Diversity
Tasmanian devils (Sarcophilus harrisii) are on the verge of extinction due to a transmissible cancer, devil facial tumour disease (DFTD). This tumour is an allograft that is transmitted between individuals without immune recognition of the tumour cells. The mechanism to explain this lack of immune recognition and acceptance is not well understood. It has been hypothesized that lack of genetic diversity at the Major Histocompatibility Complex (MHC) allowed the tumour cells to grow in genetically similar hosts without evoking an immune response to alloantigens. We conducted mixed lymphocyte reactions and skin grafts to measure functional MHC diversity in the Tasmanian devil population. The limited MHC diversity was sufficient to produce measurable mixed lymphocyte reactions. There was a wide range of responses, from low or no reaction to relatively strong responses. The highest responses occurred when lymphocytes from devils from the east of Tasmania were mixed with lymphocytes from devils from the west of Tasmania. All of the five successful skin allografts were rejected within 14 days after surgery, even though little or no MHC I and II mismatches were found. Extensive T-cell infiltration characterised the immune rejection. We conclude that Tasmanian devils are capable of allogeneic rejection. Consequently, a lack of functional allorecognition mechanisms in the devil population does not explain the transmission of a contagious cancer
Glucocorticoid Effects on the Programming of AT1b Angiotensin Receptor Gene Methylation and Expression in the Rat
Adverse events in pregnancy may ‘programme’ offspring for the later development of cardiovascular disease and hypertension. Previously, using a rodent model of programmed hypertension we have demonstrated the role of the renin-angiotensin system in this process. More recently we showed that a maternal low protein diet resulted in undermethylation of the At1b angiotensin receptor promoter and the early overexpression of this gene in the adrenal of offspring. Here, we investigate the hypothesis that maternal glucocorticoid modulates this effect on fetal DNA methylation and gene expression. We investigated whether treatment of rat dams with the 11β-hydroxylase inhibitor metyrapone, could prevent the epigenetic and gene expression changes we observed. Offspring of mothers subjected to a low protein diet in pregnancy showed reduced adrenal Agtr1b methylation and increased adrenal gene expression as we observed previously. Treatment of mothers with metyrapone for the first 14 days of pregnancy reversed these changes and prevented the appearance of hypertension in the offspring at 4 weeks of age. As a control for non-specific effects of programmed hypertension we studied offspring of mothers treated with dexamethasone from day 15 of pregnancy and showed that, whilst they had raised blood pressure, they failed to show any evidence of Agtr1b methylation or increase in gene expression. We conclude that maternal glucocorticoid in early pregnancy may induce changes in methylation and expression of the Agtr1b gene as these are clearly reversed by an 11 beta-hydroxylase inhibitor. However in later pregnancy a converse effect with dexamethasone could not be demonstrated and this may reflect either an alternative mechanism of this glucocorticoid or a stage-specific influence
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