89 research outputs found

    Assessing The Role of Anti-Filarial Antibody As A Community Infection Indicator In Areas Treated With Double- or Triple- Mass Drug Administration In Quartier Morin Haiti

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    In the global effort to eliminate lymphatic filariasis (LF) additional treatment regimens like triple drug therapy and diagnostic tools like Wb123 anti-filarial antibody have become increasingly available. This study aimed to look at two components, time and treatment regimen, in order to assess prevalence of anti-filarial antibody and its programmatic potential in the evolving Global Programme to Eliminate Lymphatic Filariasis (GPELF) setting. At year 0, 2,394 (47.4%) samples were collected from participants before mass drug administration (MDA) was administered and 2,656 (52.6%) were collected 12 months later (year 1). Blood samples from 4,939 (97.8%) participants 5 years of age and older were tested for antigen status by filariasis test strip (FTS) and dried blood spots (DBS) from 4,740 (93.9%) participants were tested for Wb123 antibodies. Our results show older individuals were more likely to be both antigen and antibody positive than younger children. Overall and across most age groups antibody prevalence was higher than antigen prevalence for both drug arms. Individuals living in localities treated with the double drug regimen had 66% greater chance of demonstrating declining antibody prevalence than those living in localities treated with the triple drug regimen. The results of this investigation support treatment with both MDA regimens and the addition of antibody testing as a surveillance tool. Our results have contributed to the evidence base surrounding population-level antibody data and help to inform programmatic decision making around treatment strategies

    Laboratory evaluation of a rapid IgG4 antibody test (BLF Rapid™) for bancroftian filariasis

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    At the end phase of the Global Programme to Eliminate Lymphatic Filariasis, antibody testing may have a role in decision-making for bancroftian filariasis–endemic areas. This study evaluated the diagnostic performance of BLF Rapid ™ , a prototype immunochromatographic IgG4-based test using BmSXP recombinant protein, for detection of bancroftian filariasis. The test was evaluated using 258 serum samples, comprising 96 samples tested at Universiti Sains Malaysia (in-house) and 162 samples tested independently at three international laboratories in the USA and India, and two laboratories in Malaysia. The independent testing involved 99 samples from Wuchereria bancrofti microfilaria or antigen positive individuals and 63 samples from people who were healthy or had other infections. The in-house evaluation showed 100% diagnostic sensitivity and specificity. The independent evaluations showed a diagnostic sensitivity of 84–100% and 100% specificity (excluding non-lymphatic filarial infections). BLF Rapid has potential as a surveillance diagnostic tool to make “Transmission Assessment Survey”–stopping decisions and conduct post-elimination surveillance

    Potential use of antibodies to provide an earlier indication of lymphatic filariasis resurgence in post–mass drug ad ministration surveillance in American Samoa

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    Background: Under the Global Programme to Eliminate Lymphatic Filariasis (LF), American Samoa conducted 7 rounds of mass drug administration (MDA) between 2000 and 2006. The territory passed transmission assessment surveys (TASs) in 2011 (TAS-1) and 2015 (TAS-2). In 2016, the territory failed TAS-3, indicating resurgence. This study aims to determine if antibodies (Abs) may have provided a timelier indication of LF resurgence in American Samoa. Methods: We examined school-level antigen (Ag) and Ab status (presence/absence of Ag- and Ab-positive children) and prevalence of single and combined Ab responses to Wb123, Bm14, and Bm33 Ags at each TAS. Pearson chi-square test and logistic regression were used to examine associations between school-level Ab prevalence in TAS-1 and TAS-2 and school-level Ag status in TAS-3. Results: Schools with higher prevalence of Wb123 Ab in TAS-2 had higher odds of being Ag-positive in TAS-3 (odds ratio [OR] 24.5, 95% confidence interval [CI] 1.2–512.7). Schools that were Ab-positive for WB123 plus Bm14, Bm33, or both Bm14 and Bm33 in TAS-2 had higher odds of being Ag-positive in TAS-3 (OR 16.0–24.5). Conclusion: Abs could provide earlier signals of resurgence and enable a timelier response. The promising role of Abs in surveillance after MDA and decision making should be further investigated in other settings

    Use of antibody tools to provide serologic evidence of elimination of Lymphatic filariasis in the Gambia

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    A current need in the global effort to eliminate lymphatic filariasis (LF) is the availability of reliable diagnostic tools that can be used to guide programmatic decisions, especially decisions made in the final stages of the program. This study conducted in The Gambia aimed to assess antifilarial antibody levels among populations living in historically highly LF-endemic areas and to evaluate the use of serologic tools to confirm the interruption of LF transmission. A total of 2,612 dried blood spots (DBSs) collected from individuals aged 1 year and above from 15 villages were tested for antibodies to Wb123 by enzyme-linked immunosorbent assay (ELISA). A subset of DBS (N = 599) was also tested for antibodies to Bm14 by ELISA. Overall, the prevalence of Wb123 was low (1.5%, 95% confidence interval [CI] 1.1-2.1%). In 7 of 15 villages (46.7%), there were no Wb123-positive individuals identified. Individuals with positive responses to Wb123 ranged in age from 3 to 100 years. Overall, Bm14 prevalence was also low (1.5%, 95% CI 0.7-2.8%). Bm14 positivity was significantly associated with older age (P < 0.001). The low levels of antibody responses to Wb123 observed in our study strongly suggest that sustainable LF transmission has likely ceased in The Gambia. In addition, our results support the conclusion that serologic tools can have a role in guiding programmatic decision making and supporting surveillance

    Reimagining the potential of Earth observations for ecosystem service assessments

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    The benefits nature provides to people, called ecosystem services, are increasingly recognized and accounted for in assessments of infrastructure development, agricultural management, conservation prioritization, and sustainable sourcing. These assessments are often limited by data, however, a gap with tremendous potential to be filled through Earth observations (EO), which produce a variety of data across spatial and temporal extents and resolutions. Despite widespread recognition of this potential, in practice few ecosystem service studies use EO. Here, we identify challenges and opportunities to using EO in ecosystem service modeling and assessment. Some challenges are technical, related to data awareness, processing, and access. These challenges require systematic investment in model platforms and data management. Other challenges are more conceptual but still systemic; they are byproducts of the structure of existing ecosystem service models and addressing them requires scientific investment in solutions and tools applicable to a wide range of models and approaches. We also highlight new ways in which EO can be leveraged for ecosystem service assessments, identifying promising new areas of research. More widespread use of EO for ecosystem service assessment will only be achieved if all of these types of challenges are addressed. This will require non-traditional funding and partnering opportunities from private and public agencies to promote data exploration, sharing, and archiving. Investing in this integration will be reflected in better and more accurate ecosystem service assessments worldwide

    A multi-layer network approach to MEG connectivity analysis

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    Recent years have shown the critical importance of inter-regional neural network connectivity in supporting healthy brain function. Such connectivity is measurable using neuroimaging techniques such as MEG, however the richness of the electrophysiological signal makes gaining a complete picture challenging. Specifically, connectivity can be calculated as statistical interdependencies between neural oscillations within a large range of different frequency bands. Further, connectivity can be computed between frequency bands. This pan-spectral network hierarchy likely helps to mediate simultaneous formation of multiple brain networks, which support ongoing task demand. However, to date it has been largely overlooked, with many electrophysiological functional connectivity studies treating individual frequency bands in isolation. Here, we combine oscillatory envelope based functional connectivity metrics with a multi-layer network framework in order to derive a more complete picture of connectivity within and between frequencies. We test this methodology using MEG data recorded during a visuomotor task, highlighting simultaneous and transient formation of motor networks in the beta band, visual networks in the gamma band and a beta to gamma interaction. Having tested our method, we use it to demonstrate differences in occipital alpha band connectivity in patients with schizophrenia compared to healthy controls. We further show that these connectivity differences are predictive of the severity of persistent symptoms of the disease, highlighting their clinical relevance. Our findings demonstrate the unique potential of MEG to characterise neural network formation and dissolution. Further, we add weight to the argument that dysconnectivity is a core feature of the neuropathology underlying schizophrenia

    An overview of 2-Styrylchromones: natural occurrence, synthesis, reactivity and biological properties

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    2-Styrylchromones are a small class of oxygen-containing heterocycles. Despite their sparse occurrence in nature, several synthetic approaches have been developed in order to synthesize a large variety of derivatives, possessing different substituents in different positions of the main core. They are also versatile building blocks in the synthesis of new heterocyclic systems and important intermediates in the search for bioactive compounds. It is our intention in this review to give a general overview on the natural occurrence, synthesis, reactivity and biological properties of 2-styrylchromones, which were published up until 2016.Thanks are due to the Instituto Politécnico de Bragança and also to the University of Aveiro and the Formación en Centros de Trabajo, Ministerio de Educación y Ciencia (FCT, MEC) for the financial support of the QOPNA research unit (FCT UID/QUI/ 00062/2013) through national funds and, where applicable, cofinanced by the Fundo Europeu De Desenvolvimento Regional (FEDER), within the PT2020 Partnership Agreement. Thanks are also due to the Portuguese NMR Network.info:eu-repo/semantics/publishedVersio
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