2,976 research outputs found

    Departures from cost-effectiveness recommendations: The impact of health system constraints on priority setting

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    The methods and application of cost-effectiveness analysis have reached an advanced stage of development. Many decision makers consider cost-effectiveness analysis to be a valid and feasible approach towards setting health priorities, and it has been extensively applied in evaluating interventions and developing evidence based clinical guidelines. However, the recommendations arising from cost-effectiveness analysis are often not implemented as intended. A fundamental reason for the failure to implement is that CEA assumes a single constraint, in the form of the budget constraint, whilst in reality decision-makers may be faced with numerous other constraints. The objective of this paper is to develop a typology of constraints that may act as barriers to implementation of cost-effectiveness recommendations. Six categories of constraints are considered: the design of the health system; costs of implementing change; system interactions between interventions; uncertainty in estimates of costs and benefits; weak governance; and political constraints. Where possible -and if applicable- for each class of constraint, the paper discusses ways in which these constraints can be taken into account by a decision maker wishing to pursue the principles of cost-effectiveness

    Infrared Exponents and Running Coupling of SU(N) Yang-Mills Theories

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    We present approximate solutions for the gluon and ghost propagators as well as the running coupling in Landau gauge Yang-Mills theories. We solve the corresponding Dyson-Schwinger equations in flat Euclidean space-time without any angular approximation. This supplements recently obtained results employing a four-torus, i.e. a compact space-time manifold, as infrared regulator. We confirm previous findings deduced from an extrapolation with tori of different volumes: the gluon propagator is weakly vanishing in the infrared and the ghost propagator is highly singular. For non-vanishing momenta our propagators are in remarkable agreement with recent lattice calculations.Comment: 11 pages, 4 figure

    Ring-Pattern Dynamics in Smectic-C* and Smectic-C_A* Freely Suspended Liquid Crystal Films

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    Ring patterns of concentric 2pi-solitons in molecular orientation, form in freely suspended chiral smectic-C films in response to an in-plane rotating electric field. We present measurements of the zero-field relaxation of ring patterns and of the driven dynamics of ring formation under conditions of synchronous winding, and a simple model which enables their quantitative description in low polarization DOBAMBC. In smectic C_A* TFMHPOBC we observe an odd-even layer number effect, with odd number layer films exhibiting order of magnitude slower relaxation rates than even layer films. We show that this rate difference is due to much larger spontaneous polarization in odd number layer films.Comment: 4 RevTeX pgs, 4 eps figures, submitted to Phys. Rev. Let

    Infertility in Muslim Refugees: A Review of the Literature

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    Many couples worldwide are affected by infertility, which is defined as an inability to conceive after at least one year of regular unprotected sexual intercourse. Many Muslim and Middle Eastern societies place a high societal value on having children and therefore, couples who are unable to conceive for various reasons often find themselves feeling stigmatized and socially isolated. Muslim refugees living in the United States face additional challenges and barriers to care due to their refugee status. This review is a synthesis of existing literature that 1) identifies Islamic viewpoints on infertility and assistive reproductive technology (ART), 2) explores the psychosocial impact of infertility for Muslim refugees, and 3) identifies barriers to care for this population. A PubMed search was conducted which yielded 592 records. After screening and removal of duplicates, 37 full-length texts were included for review. Key findings included different religious perspectives regarding various forms of ART between the two major sects of Islam (Sunni and Shia), significant social stigma and stress from infertility, and barriers to care such as high cost of treatment. Future research is needed in this area to better provide culturally competent care to Muslim couples experiencing infertility

    Bronchoscopy of Lung Cancer

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    Lung cancer is a leading cancer site in men and women with a high incidence and mortality rate. Most patients are diagnosed when the disease has already spread. An early, detection and immediate and accurate histological or cytological diagnosis are essential for a hopeful outcome. In most patients, bronchoscopy is the method of choice in establishing a suspected lung neoplasm. With the rigid and flexible method, two complementary techniques are available. The methods bear a very low mortality rate if sufficient monitoring and resuscitative instrumentation is available. Rigid bronchoscopy offers the possibility of obtaining large biopsy specimens from the tumorous tissue and provides an effective tool in the control of major haemorrhage. However, it cannot be used for the inspection of further peripherally located parts of the bronchial system and needs general anaesthesia. In contrast, the flexible method can be quickly and readily performed at practically any location using portable equipment. Bronchi can be inspected up to the 8th order and with bronchial washing, forceps biopsy, brush biopsy and fluorescence bronchoscopy techniques with a high diagnostic yield are available. This holds true, especially if these sampling techniques are used as complementary methods

    Geographic bias related to geocoding in epidemiologic studies

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    BACKGROUND: This article describes geographic bias in GIS analyses with unrepresentative data owing to missing geocodes, using as an example a spatial analysis of prostate cancer incidence among whites and African Americans in Virginia, 1990–1999. Statistical tests for clustering were performed and such clusters mapped. The patterns of missing census tract identifiers for the cases were examined by generalized linear regression models. RESULTS: The county of residency for all cases was known, and 26,338 (74%) of these cases were geocoded successfully to census tracts. Cluster maps showed patterns that appeared markedly different, depending upon whether one used all cases or those geocoded to the census tract. Multivariate regression analysis showed that, in the most rural counties (where the missing data were concentrated), the percent of a county's population over age 64 and with less than a high school education were both independently associated with a higher percent of missing geocodes. CONCLUSION: We found statistically significant pattern differences resulting from spatially non-random differences in geocoding completeness across Virginia. Appropriate interpretation of maps, therefore, requires an understanding of this phenomenon, which we call "cartographic confounding.

    Virginia Refugee’s Access to COVID 19 Health Information

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    Background: This study examined how refugees in central Virginia, United States were able to access public health information about COVID-19 and any barriers to following COVID-19 prevention guidelines. Methods: Individual interviews were conducted with refugees (n = 40) attending a family medicine clinic serving refugees and immigrants. Participants answered questions about their primary methods of obtaining COVID-19 and COVID-19 vaccine information, how they prefer to receive this information, information given by employers, precautions taken at their place of work, and current vaccination status. Results: We found that television and social media played a large role for refugees in obtaining COVID-19 information. Participants noted they preferred in-person visits and phone calls to communicate with their healthcare providers, who were important for disseminating vaccine information. Discussion: This is one of the first studies to explore how refugees obtain health information related to COVID-19 and the vaccine, and provides valuable information as vaccination outreach continues in light of new viral strains and increased need for booster vaccinations. Conclusion: The results of this study can guide development of health communication materials to engage refugee communities as the COVID-19 pandemic evolves and responses to i

    Neisseria meningitidis Has Two Independent Modes of Recognizing Its Human Receptor CEACAM1

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    BACKGROUND: Several human-restricted gram-negative bacteria exploit carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) for host colonization. For example, Neisseria meningitidis engages these human receptors via outer membrane proteins of the colony opacity-associated (Opa) protein family triggering internalization into non-phagocytic cells. PRINCIPAL FINDINGS: We report that a non-opaque strain of N. meningitidis selectively interacts with CEACAM1, but not other CEACAM family members. Using functional assays of bacterial adhesion and internalisation, microscopic analysis, and a panel of CEACAM1 deletion mutants we demonstrate that the engagement of CEACAM1 by non-opaque meningococci occurs in a manner distinct from Opa protein-mediated association. In particular, the amino-terminal domain of CEACAM1 is necessary, but not sufficient for Opa protein-independent binding, which requires multiple extracellular domains of the human receptor in a cellular context. Knock-down of CEACAM1 interferes with binding to lung epithelial cells, whereas chemical or pharmacological disruption of host protein glycosylation does not abrogate CEACAM1 recognition by non-opaque meningococci. The previously characterized meningococcal invasins NadA or Opc do not operate in a CEACAM1-dependent manner. CONCLUSIONS: The results demonstrate a mechanistically distinct, Opa protein-independent interaction between N. meningitidis and human CEACAM1. Our functional investigations suggest the presence of a second CEACAM1-binding invasin on the meningococcal surface that associates with the protein backbone and not the carbohydrate structures of CEACAM1. The redundancy in meningococcal CEACAM1-binding factors further highlights the important role of CEACAM recognition in the biology of this human-adapted pathogen

    Fluorescence resonance energy transfer (FRET)-based subcellular visualization of pathogen-induced host receptor signaling

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    <p>Abstract</p> <p>Background</p> <p>Bacteria-triggered signaling events in infected host cells are key elements in shaping the host response to pathogens. Within the eukaryotic cell, signaling complexes are spatially organized. However, the investigation of protein-protein interactions triggered by bacterial infection in the cellular context is technically challenging. Here, we provide a methodological approach to exploit fluorescence resonance energy transfer (FRET) to visualize pathogen-initiated signaling events in human cells.</p> <p>Results</p> <p>Live-cell microscopy revealed the transient recruitment of the Src family tyrosine kinase Hck upon bacterial engagement of the receptor carcinoembryonic antigen-related cell adhesion molecule 3 (CEACAM3). In cells expressing a CEACAM3 variant lacking the cytoplasmic domain, the Src homology 2 (SH2) domain of Hck (Hck-SH2) was not recruited, even though bacteria still bound to the receptor. FRET measurements on the basis of whole cell lysates revealed intimate binding between Hck-SH2 (using enhanced yellow fluorescent protein (YPet)-Hck-SH2) and the tyrosine-phosphorylated enhanced cyan fluorescent protein-labeled cytoplasmic domain of wild-type CEACAM3 (CEACAM3 WT-CyPet) and a flow cytometry-based FRET approach verified this association in intact cells. Using confocal microscopy and acceptor photobleaching, FRET between Hck-SH2 and CEACAM3 was localized to the sites of bacteria-host cell contact.</p> <p>Conclusion</p> <p>These data demonstrate not only the intimate binding of the SH2 domain of Hck to the tyrosine-phosphorylated cytoplasmic domain of CEACAM3 in intact cells, but furthermore, FRET measurements allow the subcellular localization of this process during bacterial infection. FRET-based assays are valuable tools to resolve bacteria-induced protein-protein interactions in the context of the intact host cell.</p
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