6,583 research outputs found

    Religious research as kingpin in the fight against poverty and AIDS in the Western Cape, South Africa

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    This article describes the researchers’ efforts to apply the principles of Participatory Action Research (PAR), specifically participation, through the direct involvement of church members in the research. It includes involving them in the design of questionnaires, training and utilizing them as fieldworkers, and finally disseminating the results of the research via workshops aimed at strategizing for change. The research is based on two hypotheses, the first being that, churches and their members are intensely involved in serving both the needs of their own members, as well as the needs of the larger community; and secondly, that churches do not work alone, but are part of networks with other agencies to accomplish their goals. At the outset the article outlines the challenges and points of departure, followed by a chronological account of how this approach was applied in Paarl, a South African community. Finally, an overview of the results of the project is provided

    The effect of orientation of retinal configuration upon accommodation and convergence

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    The effect of orientation of retinal configuration upon accommodation and convergenc

    Ixodes ricinus Tick Lipocalins: Identification, Cloning, Phylogenetic Analysis and Biochemical Characterization

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    BACKGROUND: During their blood meal, ticks secrete a wide variety of proteins that interfere with their host's defense mechanisms. Among these proteins, lipocalins play a major role in the modulation of the inflammatory response. METHODOLOGY/PRINCIPAL FINDINGS: Screening a cDNA library in association with RT-PCR and RACE methodologies allowed us to identify 14 new lipocalin genes in the salivary glands of the Ixodes ricinus hard tick. A computational in-depth structural analysis confirmed that LIRs belong to the lipocalin family. These proteins were called LIR for "Lipocalin from I. ricinus" and numbered from 1 to 14 (LIR1 to LIR14). According to their percentage identity/similarity, LIR proteins may be assigned to 6 distinct phylogenetic groups. The mature proteins have calculated pM and pI varying from 21.8 kDa to 37.2 kDa and from 4.45 to 9.57 respectively. In a western blot analysis, all recombinant LIRs appeared as a series of thin bands at 50-70 kDa, suggesting extensive glycosylation, which was experimentally confirmed by treatment with N-glycosidase F. In addition, the in vivo expression analysis of LIRs in I. ricinus, examined by RT-PCR, showed homogeneous expression profiles for certain phylogenetic groups and relatively heterogeneous profiles for other groups. Finally, we demonstrated that LIR6 codes for a protein that specifically binds leukotriene B4. CONCLUSIONS/SIGNIFICANCE: This work confirms that, regarding their biochemical properties, expression profile, and sequence signature, lipocalins in Ixodes hard tick genus, and more specifically in the Ixodes ricinus species, are segregated into distinct phylogenetic groups suggesting potential distinct function. This was particularly demonstrated by the ability of LIR6 to scavenge leukotriene B4. The other LIRs did not bind any of the ligands tested, such as 5-hydroxytryptamine, ADP, norepinephrine, platelet activating factor, prostaglandins D2 and E2, and finally leukotrienes B4 and C4.Journal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe

    WhatsApp-propriate? A retrospective content analysis of WhatsApp use and potential breaches in confidentiality among a team of doctors at a district hospital, South Africa

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    Background. There has been a steady increase in the use of electronic media and instant messaging among healthcare professionals, where it has been almost universally adopted in the workplace. The use of WhatsApp and its perceived benefits in healthcare have been extensively studied; however, there are concerns regarding the potential for ethical breaches in confidentiality through shared electronic patient information.Objectives. To identify the usage characteristics and incidence of shared patient information with WhatsApp use in a team of medical doctors in an unobserved and unregulated setting.Methods. We conducted a retrospective cross-sectional content analysis of WhatsApp messages (n=3 340) among a team of 20 doctors in a South African district hospital over 6 months. All messages found within this time period were allocated unique identifiers. The text and image messages were thematically grouped into four categories, i.e. clinical care, resource allocation, social and administrative. Messages that contained patient-identifying information were included in the analysis.Results. Of a total of 3 340 messages sent, 220 (6.6%) contained patient-identifying information. Of these, 109 (3.3%) contained non-anonymised patient information, while in 111 (3.3%) messages, the information was anonymised. The likelihood of sharing patient identifiers was proportionally much higher in shared images (odds ratio (OR) 5.1; 95% confidence interval (CI) 3.2 - 8.2; p<0.0001) compared with text messages, and in messages that related to clinical care (OR 9.3; 95% CI 2.2 - 38.8; p=0.0023) compared with those sent for resource allocation, and social or administrative purposes.Conclusions. Non-anonymised patient identifiers were found in 3.3% of messages, constituting the potential for breaching patient confidentiality. While WhatsApp groups have significant utility in co-ordinating aspects of clinical care, resource allocation, as well as social and administrative functions, the safe use of WhatsApp should be promoted to ensure that patient confidentiality is maintained

    Dynamics of epizootic hemorrhagic disease virus infection within the vector, Culicoides sonorensis (Diptera: Ceratopogonidae)

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    Citation: Mills, M. K., Ruder, M. G., Nayduch, D., Michel, K., & Drolet, B. S. (2017). Dynamics of epizootic hemorrhagic disease virus infection within the vector, Culicoides sonorensis (Diptera: Ceratopogonidae). PLOS ONE, 12(11), e0188865. https://doi.org/10.1371/journal.pone.0188865Culicoides sonorensis biting midges are confirmed vectors of epizootic hemorrhagic disease virus (EHDV), which causes mortality in white-tailed deer and ruminant populations. Currently, of the seven EHDV serotypes, only 1, 2, and 6 are detected in the USA, and very few studies have focused on the infection time course of these serotypes within the midge. The objective of this current research was to characterize EHDV-2 infection within the midge by measuring infection prevalence, virus dissemination, and viral load over the course of infection. Midges were fed a blood meal containing 106.9 PFU/ml EHDV-2, collected every 12 h from 0–2 days post feeding (dpf) and daily from 3–10 dpf, and cohorts of 20 C. sonorensis were processed using techniques that assessed EHDV infection and dissemination. Cytopathic effect assays and quantitative (q)PCR were used to determine infection prevalence, revealing a 50% infection rate by 10 dpf using both methods. Using immunohistochemistry, EHDV-2 infection was detectable at 5 dpf, and shown to disseminate from the midgut to other tissues, including fat body, eyes, and salivary glands by 5 dpf. Stain intensity increased from 5–8 dpf, indicating replication of EHDV-2 in secondary infection sites after dissemination. This finding is also supported by trends in viral load over time as determined by plaque assays and qPCR. An increase in titer between 4–5 dpf correlated with viral replication in the midgut as seen with staining at day 5, while the subsequent gradual increase in viral load from 8–10 dpf suggested viral replication in midges with disseminated infection. Overall, the data presented herein suggest that EHDV-2 disseminates via the hemolymph to secondary infection sites throughout the midge and demonstrate a high potential for transmission at five days at 25°C after an infective blood-meal

    Searching for a light Fermiophobic Higgs Boson at the Tevatron

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    We propose new production mechanisms for light fermiophobic Higgs bosons (hfh_f) with suppressed couplings to vector bosons (VV) at the Fermilab Tevatron. These mechanisms (e.g. qqH±hfqq'\to H^\pm h_f) are complementary to the conventional process qqVhfqq'\to Vh_f, which suffers from a strong suppression of 1/tan2β1/\tan^2\beta in realistic models with a hfh_f. The new mechanisms extend the coverage at the Tevatron Run II to the larger tanβ\tan\beta region, and offer the possibility of observing new event topologies with up to 4 photons.Comment: 15 pages, including 5 eps-figure

    Visualization and Analysis Techniques for Three Dimensional Information Acquired by Confocal Microscopy

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    Confocal Scanning Laser Microscopy (CSLM) is particularly well suited for the acquisition of 3-dimensional data of microscopic objects. In the CSLM a specific volume in the object is sampled during the imaging process and the result is stored in a digital computer as a three-dimensional memory array. Optimal use of these data requires both the development of effective visual representations as well as analysis methods. In addition to the well known stereoscopic representation method a number of alternatives for various purposes are presented. When rendering in terms of solid-looking or semitransparent objects is required, an algorithm based on a simulated process of excitation and fluorescence is very suitable. Graphic techniques can be used to examine the 3-dimensional shape of surfaces. For (near-)real time applications a representation method should not require extensive previous data-processing or analysis. From the very extensive field of 3-D image analysis two examples are given

    Nuttalliella namaqua: A Living Fossil and Closest Relative to the Ancestral Tick Lineage: Implications for the Evolution of Blood-Feeding in Ticks

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    Ticks are monophyletic and composed of the hard (Ixodidae) and soft (Argasidae) tick families, as well as the Nuttalliellidae, a family with a single species, Nuttalliella namaqua. Significant biological differences in lifestyle strategies for hard and soft ticks suggest that various blood-feeding adaptations occurred after their divergence. The phylogenetic relationships between the tick families have not yet been resolved due to the lack of molecular data for N. namaqua. This tick possesses a pseudo-scutum and apical gnathostoma as observed for ixodids, has a leathery cuticle similar to argasids and has been considered the evolutionary missing link between the two families. Little knowledge exists with regard to its feeding biology or host preferences. Data on its biology and systematic relationship to the other tick families could therefore be crucial in understanding the evolution of blood-feeding behaviour in ticks. Live specimens were collected and blood meal analysis showed the presence of DNA for girdled lizards from the Cordylid family. Feeding of ticks on lizards showed that engorgement occurred rapidly, similar to argasids, but that blood meal concentration occurs via malpighian excretion of water. Phylogenetic analysis of the 18S nuclear and 16S mitochondrial genes indicate that N. namaqua grouped basal to the main tick families. The data supports the monophyly of all tick families and suggests the evolution of argasid-like blood-feeding behaviour in the ancestral tick lineage. Based on the data and considerations from literature we propose an origin for ticks in the Karoo basin of Gondwanaland during the late Permian. The nuttalliellid family almost became extinct during the End Permian event, leaving N. namaqua as the closest living relative to the ancestral tick lineage and the evolutionary missing link between the tick families

    Comparative salivary gland transcriptomics of sandfly vectors of visceral leishmaniasis

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    BACKGROUND: Immune responses to sandfly saliva have been shown to protect animals against Leishmania infection. Yet very little is known about the molecular characteristics of salivary proteins from different sandflies, particularly from vectors transmitting visceral leishmaniasis, the fatal form of the disease. Further knowledge of the repertoire of these salivary proteins will give us insights into the molecular evolution of these proteins and will help us select relevant antigens for the development of a vector based anti-Leishmania vaccine. RESULTS: Two salivary gland cDNA libraries from female sandflies Phlebotomus argentipes and P. perniciosus were constructed, sequenced and proteomic analysis of the salivary proteins was performed. The majority of the sequenced transcripts from the two cDNA libraries coded for secreted proteins. In this analysis we identified transcripts coding for protein families not previously described in sandflies. A comparative sandfly salivary transcriptome analysis was performed by using these two cDNA libraries and two other sandfly salivary gland cDNA libraries from P. ariasi and Lutzomyia longipalpis, also vectors of visceral leishmaniasis. Full-length secreted proteins from each sandfly library were compared using a stand-alone version of BLAST, creating formatted protein databases of each sandfly library. Related groups of proteins from each sandfly species were combined into defined families of proteins. With this comparison, we identified families of salivary proteins common among all of the sandflies studied, proteins to be genus specific and proteins that appear to be species specific. The common proteins included apyrase, yellow-related protein, antigen-5, PpSP15 and PpSP32-related protein, a 33-kDa protein, D7-related protein, a 39- and a 16.1- kDa protein and an endonuclease-like protein. Some of these families contained multiple members, including PPSP15-like, yellow proteins and D7-related proteins suggesting gene expansion in these proteins. CONCLUSION: This comprehensive analysis allows us the identification of genus- specific proteins, species-specific proteins and, more importantly, proteins common among these different sandflies. These results give us insights into the repertoire of salivary proteins that are potential candidates for a vector-based vaccine
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