237 research outputs found

    The Dutch health insurance reform: switching between insurers, a comparison between the general population and the chronically ill and disabled

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    Background: On 1 January 2006 a number of far-reaching changes in the Dutch health insurance system came into effect. In the new system of managed competition consumer mobility plays an important role. Consumers are free to change their insurer and insurance plan every year. The idea is that consumers who are not satisfied with the premium or quality of care provided will opt for a different insurer. This would force insurers to strive for good prices and quality of care. Internationally, the Dutch changes are under the attention of both policy makers and researchers. Questions answered in this article relate to switching behaviour, reasons for switching, and differences between population categories. Methods: Postal questionnaires were sent to 1516 members of the Dutch Health Care Consumer Panel and to 3757 members of the National Panel of the Chronically ill and Disabled (NPCD) in April 2006. The questionnaire was returned by 1198 members of the Consumer Panel (response 79%) and by 3211 members of the NPCD (response 86%). Among other things, questions were asked about choices for a health insurer and insurance plan and the reasons for this choice. Results: Young and healthy people switch insurer more often than elderly or people in bad health. The chronically ill and disabled do not switch less often than the general population when both populations are comparable on age, sex and education. For the general population, premium is more important than content, while the chronically ill and disabled value content of the insurance package as well. However, quality of care is not important for either group as a reason for switching. Conclusion: There is increased mobility in the new system for both the general population and the chronically ill and disabled. This however is not based on quality of care. If reasons for switching are unrelated to the quality of care, it is hard to believe that switching influences the quality of care. As yet there are no signs of barriers to switch insurer for the chronically ill and disabled. This however could change in the future and it is therefore important to monitor changes.

    Solulin reduces infarct volume and regulates gene-expression in transient middle cerebral artery occlusion in rats

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    <p>Abstract</p> <p>Background</p> <p>Thrombolysis after acute ischemic stroke has only proven to be beneficial in a subset of patients. The soluble recombinant analogue of human thrombomodulin, Solulin, was studied in an <it>in vivo </it>rat model of acute ischemic stroke.</p> <p>Methods</p> <p>Male SD rats were subjected to 2 hrs of transient middle cerebral artery occlusion (tMCAO). Rats treated with Solulin intravenously shortly before reperfusion were compared to rats receiving normal saline i.v. with respect to infarct volumes, neurological deficits and mortality. Gene expression of IL-6, IL-1Ī², TNF-Ī±, MMP-9, CD11B and GFAP were semiquantitatively analyzed by rtPCR of the penumbra.</p> <p>Results</p> <p>24 hrs after reperfusion, rats were neurologically tested, euthanized and infarct volumes determined. Solulin significantly reduced mean total (p = 0.001), cortical (p = 0.002), and basal ganglia (p = 0.036) infarct volumes. Hippocampal infarct volumes (p = 0.191) were not significantly affected. Solulin significantly downregulated the expression of IL-1Ī² (79%; p < 0.001), TNF-Ī± (59%; p = 0.001), IL-6 (47%; p = 0.04), and CD11B (49%; p = 0.001) in the infarcted cortex compared to controls.</p> <p>Conclusions</p> <p>Solulin reduced mean total, cortical and basal ganglia infarct volumes and regulated a subset of cytokines and proteases after tMCAO suggesting the potency of this compound for therapeutic interventions.</p

    Analysis of feedback loops and robustness in network evolution based on Boolean models

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    <p>Abstract</p> <p>Background</p> <p>Many biological networks such as protein-protein interaction networks, signaling networks, and metabolic networks have topological characteristics of a scale-free degree distribution. Preferential attachment has been considered as the most plausible evolutionary growth model to explain this topological property. Although various studies have been undertaken to investigate the structural characteristics of a network obtained using this growth model, its dynamical characteristics have received relatively less attention.</p> <p>Results</p> <p>In this paper, we focus on the robustness of a network that is acquired during its evolutionary process. Through simulations using Boolean network models, we found that preferential attachment increases the number of coupled feedback loops in the course of network evolution. Whereas, if networks evolve to have more coupled feedback loops rather than following preferential attachment, the resulting networks are more robust than those obtained through preferential attachment, although both of them have similar degree distributions.</p> <p>Conclusion</p> <p>The presented analysis demonstrates that coupled feedback loops may play an important role in network evolution to acquire robustness. The result also provides a hint as to why various biological networks have evolved to contain a number of coupled feedback loops.</p

    Ethnic entrepreneurs and online home-based businesses: an exploratory study

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    This exploratory, qualitative study considers how online home-based businesses offer opportunities for ethnic entrepreneurs to ā€˜break outā€™ of traditional highly competitive and low margin sectors. Previous studies have found a positive association between ethnic minoritiesā€™ high levels of entrepreneurship and home computer use in ethnic groups. Despite these associations, previous studies have overlooked the particular opportunities offered by home-based online businesses to ethnic entrepreneurs. The study adopts mixed embeddedness as a theoretical lens to guide interviews with 22 ethnic entrepreneurs who have started online home-based businesses in the UK. We find online home-based businesses offer ethnic entrepreneurs novel opportunities to draw on their ethnic advantages and address the constraints they face. The unique affordances of this type of business allow entrepreneurs to develop the necessary IT skills by self-learning and experimentation and to sub-contract more difficult or time consuming aspects to others. The findings also show that, consistent with the theory of mixed embeddedness, whilst the entrepreneurs are influenced by social, economic and institutional forces, online businesses allow them to exert their own agency and provide opportunities to uniquely shape these forces

    ATP release via anion channels

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    ATP serves not only as an energy source for all cell types but as an ā€˜extracellular messenger-for autocrine and paracrine signalling. It is released from the cell via several different purinergic signal efflux pathways. ATP and its Mg2+ and/or H+ salts exist in anionic forms at physiological pH and may exit cells via some anion channel if the pore physically permits this. In this review we survey experimental data providing evidence for and against the release of ATP through anion channels. CFTR has long been considered a probable pathway for ATP release in airway epithelium and other types of cells expressing this protein, although non-CFTR ATP currents have also been observed. Volume-sensitive outwardly rectifying (VSOR) chloride channels are found in virtually all cell types and can physically accommodate or even permeate ATP4- in certain experimental conditions. However, pharmacological studies are controversial and argue against the actual involvement of the VSOR channel in significant release of ATP. A large-conductance anion channel whose open probability exhibits a bell-shaped voltage dependence is also ubiquitously expressed and represents a putative pathway for ATP release. This channel, called a maxi-anion channel, has a wide nanoscopic pore suitable for nucleotide transport and possesses an ATP-binding site in the middle of the pore lumen to facilitate the passage of the nucleotide. The maxi-anion channel conducts ATP and displays a pharmacological profile similar to that of ATP release in response to osmotic, ischemic, hypoxic and salt stresses. The relation of some other channels and transporters to the regulated release of ATP is also discussed

    MicroRNAs hsa-miR-99b, hsa-miR-330, hsa-miR-126 and hsa-miR-30c: Potential Diagnostic Biomarkers in Natural Killer (NK) Cells of Patients with Chronic Fatigue Syndrome (CFS)/ Myalgic Encephalomyelitis (ME)

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    Chronic Fatigue Syndrome (CFS/ME) is a complex multisystem disease of unknown aetiology which causes debilitating symptoms in up to 1% of the global population. Although a large cohort of genes have been shown to exhibit altered expression in CFS/ME patients, it is currently unknown whether microRNA (miRNA) molecules which regulate gene translation contribute to disease pathogenesis. We hypothesized that changes in microRNA expression in patient leukocytes contribute to CFS/ME pathology, and may therefore represent useful diagnostic biomarkers that can be detected in the peripheral blood of CFS/ME patients.miRNA expression in peripheral blood mononuclear cells (PBMC) from CFS/ME patients and healthy controls was analysed using the Ambion Bioarray V1. miRNA demonstrating differential expression were validated by qRT-PCR and then replicated in fractionated blood leukocyte subsets from an independent patient cohort. The CFS/ME associated miRNA identified by these experiments were then transfected into primary NK cells and gene expression analyses conducted to identify their gene targets.Microarray analysis identified differential expression of 34 miRNA, all of which were up-regulated. Four of the 34 miRNA had confirmed expression changes by qRT-PCR. Fractionating PBMC samples by cell type from an independent patient cohort identified changes in miRNA expression in NK-cells, B-cells and monocytes with the most significant abnormalities occurring in NK cells. Transfecting primary NK cells with hsa-miR-99b or hsa-miR-330-3p, resulted in gene expression changes consistent with NK cell activation but diminished cytotoxicity, suggesting that defective NK cell function contributes to CFS/ME pathology.This study demonstrates altered microRNA expression in the peripheral blood mononuclear cells of CFS/ME patients, which are potential diagnostic biomarkers. The greatest degree of miRNA deregulation was identified in NK cells with targets consistent with cellular activation and altered effector function

    Transcriptomic analysis supports similar functional roles for the two thymuses of the tammar wallaby

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    Background: The thymus plays a critical role in the development and maturation of T-cells. Humans have a single thoracic thymus and presence of a second thymus is considered an anomaly. However, many vertebrates have multiple thymuses. The tammar wallaby has two thymuses: a thoracic thymus (typically found in all mammals) and a dominant cervical thymus. Researchers have known about the presence of the two wallaby thymuses since the 1800s, but no genome-wide research has been carried out into possible functional differences between the two thymic tissues. Here, we used pyrosequencing to compare the transcriptomes of a cervical and thoracic thymus from a single 178 day old tammar wallaby.Results: We show that both the tammar thoracic and the cervical thymuses displayed gene expression profiles consistent with roles in T-cell development. Both thymuses expressed genes that mediate distinct phases of T-cells differentiation, including the initial commitment of blood stem cells to the T-lineage, the generation of T-cell receptor diversity and development of thymic epithelial cells. Crucial immune genes, such as chemokines were also present. Comparable patterns of expression of non-coding RNAs were seen. 67 genes differentially expressed between the two thymuses were detected, and the possible significance of these results are discussed.Conclusion: This is the first study comparing the transcriptomes of two thymuses from a single individual. Our finding supports that both thymuses are functionally equivalent and drive T-cell development. These results are an important first step in the understanding of the genetic processes that govern marsupial immunity, and also allow us to begin to trace the evolution of the mammalian immune system
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