903 research outputs found

    Etiology of Severe Non-malaria Febrile Illness in Northern Tanzania: A Prospective Cohort Study.

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    The syndrome of fever is a commonly presenting complaint among persons seeking healthcare in low-resource areas, yet the public health community has not approached fever in a comprehensive manner. In many areas, malaria is over-diagnosed, and patients without malaria have poor outcomes. We prospectively studied a cohort of 870 pediatric and adult febrile admissions to two hospitals in northern Tanzania over the period of one year using conventional standard diagnostic tests to establish fever etiology. Malaria was the clinical diagnosis for 528 (60.7%), but was the actual cause of fever in only 14 (1.6%). By contrast, bacterial, mycobacterial, and fungal bloodstream infections accounted for 85 (9.8%), 14 (1.6%), and 25 (2.9%) febrile admissions, respectively. Acute bacterial zoonoses were identified among 118 (26.2%) of febrile admissions; 16 (13.6%) had brucellosis, 40 (33.9%) leptospirosis, 24 (20.3%) had Q fever, 36 (30.5%) had spotted fever group rickettsioses, and 2 (1.8%) had typhus group rickettsioses. In addition, 55 (7.9%) participants had a confirmed acute arbovirus infection, all due to chikungunya. No patient had a bacterial zoonosis or an arbovirus infection included in the admission differential diagnosis. Malaria was uncommon and over-diagnosed, whereas invasive infections were underappreciated. Bacterial zoonoses and arbovirus infections were highly prevalent yet overlooked. An integrated approach to the syndrome of fever in resource-limited areas is needed to improve patient outcomes and to rationally target disease control efforts

    Microplastic burden in marine benthic invertebrates depends on species traits and feeding ecology within biogeographical provinces

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    This is the final version. Available on open access from Nature Research via the DOI in this recordData availability: The research data supporting this publication are openly available from Harvard Dataverse at: https://doi.org/10.7910/DVN/E57LOA. The data for the Van Sebille 2015 model can be found at: https://figshare.com/collections/data_of_Van_Sebille_et_al_2015_ERL_paper/5764184. Ocean boundaries (Spalding’s Provinces) used in Fig. 1 are freely available at: https://www.worldwildlife.org/publications/marine-ecoregions-of-the-world-a-bioregionalization-of-coastal-and-shelf-areas. Longhurst provinces used as a geographical variable in the initial analysis are freely available from: https://www.marineregions.org/gazetteer.php?p=details&id=22538. The world country shapefiles used in Fig. 1 are available from ESRI at: https://hub.arcgis.com/datasets/esri::world-countries-generalized/about and available for use under the ESRI Master License Agreement. Taxonomy for all species was verified and curated using the World Register of Marine Species match taxa function available at: https://www.marinespecies.org/aphia.php?p=match. Biological trait categories were modified using those provided by the Marine Life Information Network (MarLIN) Biological Traits Information Catalogue (BIOTIC) available at: https://www.marlin.ac.uk/biotic/resources.php. Latitudes and Longitudes when not specifically mentioned in the individual study were approximated using Google Maps.The microplastic body burden of marine animals is often assumed to reflect levels of environmental contamination, yet variations in feeding ecology and regional trait expression could also affect a species' risk of contaminant uptake. Here, we explore the global inventory of individual microplastic body burden for invertebrate species inhabiting marine sediments across 16 biogeographic provinces. We show that individual microplastic body burden in benthic invertebrates cannot be fully explained by absolute levels of microplastic contamination in the environment, because interspecific differences in behaviour and feeding ecology strongly determine microplastic uptake. Our analyses also indicate a degree of species-specific particle selectivity; likely associated with feeding biology. Highest microplastic burden occurs in the Yellow and Mediterranean Seas and, contrary to expectation, amongst omnivores, predators, and deposit feeders rather than suspension feeding species. Our findings highlight the inadequacy of microplastic uptake risk assessments based on inventories of environmental contamination alone, and the need to understand how species behaviour and trait expression covary with microplastic contamination.Natural Environment Research Council (NERC

    A case of septicaemic anthrax in an intravenous drug user

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    <p><b>Background:</b> In 2000, Ringertz et al described the first case of systemic anthrax caused by injecting heroin contaminated with anthrax. In 2008, there were 574 drug related deaths in Scotland, of which 336 were associated with heroin and or morphine. We report a rare case of septicaemic anthrax caused by injecting heroin contaminated with anthrax in Scotland.</p> <p><b>Case Presentation:</b> A 32 year old intravenous drug user (IVDU), presented with a 12 hour history of increasing purulent discharge from a chronic sinus in his left groin. He had a tachycardia, pyrexia, leukocytosis and an elevated C-reactive protein (CRP). He was treated with Vancomycin, Clindamycin, Ciprofloxacin, Gentamicin and Metronidazole. Blood cultures grew Bacillus anthracis within 24 hours of presentation. He had a computed tomography (CT) scan and magnetic resonance imagining (MRI) of his abdomen, pelvis and thighs performed. These showed inflammatory change relating to the iliopsoas and an area of necrosis in the adductor magnus.</p> <p>He underwent an exploration of his left thigh. This revealed chronically indurated subcutaneous tissues with no evidence of a collection or necrotic muscle. Treatment with Vancomycin, Ciprofloxacin and Clindamycin continued for 14 days. Negative Pressure Wound Therapy (NPWT) device was applied utilising the Venturi™ wound sealing kit. Following 4 weeks of treatment, the wound dimensions had reduced by 77%.</p> <p><b>Conclusions:</b> Although systemic anthrax infection is rare, it should be considered when faced with severe cutaneous infection in IVDU patients. This case shows that patients with significant bacteraemia may present with no signs of haemodynamic compromise. Prompt recognition and treatment with high dose IV antimicrobial therapy increases the likelihood of survival. The use of simple wound therapy adjuncts such as NPWT can give excellent wound healing results.</p&gt

    Protocol for a human in vivo model of acute cigarette smoke inhalation challenge in smokers with COPD: monitoring the nasal and systemic immune response using a network biology approach

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    Introduction: Cigarette smoke contributes to a diverse range of diseases including chronic obstructive pulmonary disease (COPD), cardiovascular disorders and many cancers. There currently is a need for human challenge models, to assess the acute effects of a controlled cigarette smoke stimulus, followed by serial sampling of blood and respiratory tissue for advanced molecular profiling. We employ precision sampling of nasal mucosal lining fluid by absorption to permit soluble mediators measurement in eluates. Serial nasal curettage was used for transcriptomic analysis of mucosal tissue. Methods and analysis: Three groups of strictly defined patients will be studied: 12 smokers with COPD (GOLD Stage 2) with emphysema, 12 matched smokers with normal lung function and no evidence of emphysema, and 12 matched never smokers with normal spirometry. Patients in the smoking groups are current smokers, and will be given full support to stop smoking immediately after this study. In giving a controlled cigarette smoke stimulus, all patients will have abstained from smoking for 12 h, and will smoke two cigarettes with expiration through the nose in a ventilated chamber. Before and after inhalation of cigarette smoke, a series of samples will be taken from the blood, nasal mucosal lining fluid and nasal tissue by curettage. Analysis of plasma nicotine and metabolites in relation to levels of soluble inflammatory mediators in nasal lining fluid and blood, as well as assessing nasal transcriptomics, ex vivo blood platelet aggregation and leucocyte responses to toll-like receptor agonists will be undertaken. Implications: Development of acute cigarette smoke challenge models has promise for the study of molecular effects of smoking in a range of pathological processes.This study was funded by the Wellcome Trust and Dainippon Sumitomo Pharma Co Ltd, Osaka, Japan. Supported by: Dainippon Sumitomo Pharma Co Ltd, Osaka, Japan National Institute of Healthcare Research (Grant No: R3101002), NIHR Imperial Biomedical Research Centre (NIHR BMRC), Imperial Academic Health Science Centre (AHSC), Imperial Centre for Respiratory Infection (CRI, Grant No: 083567/Z/07/Z), Wellcome Trust (Grant No: 083429/Z/07/Z)

    New occurrences of the White River Ash (east lobe) in Subarctic Canada and utility for estimating freshwater reservoir effect in lake sediment archives

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    The freshwater reservoir effect (FRE) in the Canadian Subarctic complicates development of high-resolution age-depth models based on radiocarbon dates from lake sediments. Volcanic ashfall layers (tephras) provide chronostratigraphic markers that can be used to estimate age offsets. We describe the first recorded occurrence of a visible tephra in a lacustrine sequence in the central Northwest Territories. The tephra, observed in Pocket Lake, near Yellowknife, is geochemically and stratigraphically attributed to the White River Ash east lobe (WRAe; 833–850 CE; 1117–1100 cal BP), which originated from an eruption of Mount Churchill, Alaska. We also observed the WRAe as a cryptotephra in Bridge Lake, 130 km to the NE, suggesting that records of this tephra are potentially widespread in CNT lakes. The identification of this tephra presents opportunities for use of the WRAe as a dating tool in the region and to quantify the magnitude of the FRE in order to correct radiocarbon age-depth models. Two well-dated sediment cores from Pocket Lake, containing a visible WRAe record, indicate a FRE of 200 years at the time of the ash deposition, which matches closely with the estimated FRE of 245 years at the lake sediment-water interface. Although additional results from other lakes in the region are required, this finding implies that FRE estimates for the late Holocene in the region, may be based either on down-core WRAe/radiocarbon age model offsets, or on radiocarbon dates obtained from the sediment-water interface

    Minimal Conformal Technicolor and Precision Electroweak Tests

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    We study the minimal model of conformal technicolor, an SU(2) gauge theory near a strongly coupled conformal fixed point, with conformal symmetry softly broken by technifermion mass terms. Conformal symmetry breaking triggers chiral symmetry breaking in the pattern SU(4) -> Sp(4), which gives rise to a pseudo-Nambu-Goldstone boson that can act as a composite Higgs boson. The top quark is elementary, and the top and electroweak gauge loop contributions to the Higgs mass are cut off entirely by Higgs compositeness. In particular, the model requires no top partners and no "little Higgs" mechanism. A nontrivial vacuum alignment results from the interplay of the top loop and technifermion mass terms. The composite Higgs mass is completely determined by the top loop, in the sense that m_h/m_t is independent of the vacuum alignment and is computable by a strong-coupling calculation. There is an additional composite pseudoscalar A with mass larger than m_h and suppressed direct production at LHC. We discuss the electroweak fit in this model in detail. Corrections to Z -> bb and the T parameter from the top sector are suppressed by the enhanced Sp(4) custodial symmetry. Even assuming that the strong contribution to the S parameter is positive and usuppressed, a good electroweak fit can be obtained for v/f ~ 0.25, where v and f are the electroweak and chiral symmetry breaking scales respectively. This requires fine tuning at the 10% level.Comment: 34 pages, 4 figures; v2: updated precision electroweak fi

    Pre-cooling for endurance exercise performance in the heat: a systematic review.

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    PMCID: PMC3568721The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1741-7015/10/166. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Endurance exercise capacity diminishes under hot environmental conditions. Time to exhaustion can be increased by lowering body temperature prior to exercise (pre-cooling). This systematic literature review synthesizes the current findings of the effects of pre-cooling on endurance exercise performance, providing guidance for clinical practice and further research

    Stationary Black Holes: Uniqueness and Beyond

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    The spectrum of known black-hole solutions to the stationary Einstein equations has been steadily increasing, sometimes in unexpected ways. In particular, it has turned out that not all black-hole-equilibrium configurations are characterized by their mass, angular momentum and global charges. Moreover, the high degree of symmetry displayed by vacuum and electro-vacuum black-hole spacetimes ceases to exist in self-gravitating non-linear field theories. This text aims to review some developments in the subject and to discuss them in light of the uniqueness theorem for the Einstein-Maxwell system.Comment: Major update of the original version by Markus Heusler from 1998. Piotr T. Chru\'sciel and Jo\~ao Lopes Costa succeeded to this review's authorship. Significantly restructured and updated all sections; changes are too numerous to be usefully described here. The number of references increased from 186 to 32

    Preventing childhood obesity: what works?

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    Rates of overweight in North American children and adolescents have increased dramatically since the 1970s. Childhood obesity has reached epidemic proportions and calls for prevention and treatment programs to reverse this trend have been made. However, the evidence base needed for effective action is still incomplete, especially for childhood obesity prevention programs. This paper focuses on primary prevention of childhood obesity and has three aims: (1) to briefly describe current primary prevention approaches for childhood obesity and the evidence for their impact; (2) to elucidate promising, but untested intervention strategies using an ecological framework and evidence from experimental and epidemiological research on factors influencing children\u27s eating and weight status; and (3) to introduce a multiphase strategy for screening intervention components and building and evaluating potent interventions for childhood obesity. Most childhood obesity prevention programs have focused on school-aged children and have had little success. We suggest that, given these findings, prevention efforts should be expanded to explore other contexts in which children live as possible settings for intervention efforts, including the family and childcare settings. Given that 25% of preschool children are already overweight, intervening with children before school entry should be a priority. A review of experimental research on the developing controls of food intake in infancy and childhood suggests possible intervention strategies, focusing on parenting and aspects of the feeding environment. Epidemiological findings point to even earlier modifiable risk factors, including gestational weight gain, maternal prepregnancy weight, and formula feeding. However, the potential impact of altering these risk factors remains to be evaluated. In response to this problem, we suggest a new, multiphase method for accomplishing this, including screening intervention components, refining intervention designs and confirming component efficacy to build and evaluate potent, optimized interventions

    Microbial community composition in sediments resists perturbation by nutrient enrichment

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    Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in The ISME Journal 5 (2011): 1540–1548, doi:10.1038/ismej.2011.22.Functional redundancy in bacterial communities is expected to allow microbial assemblages to survive perturbation by allowing continuity in function despite compositional changes in communities. Recent evidence suggests, however, that microbial communities change both composition and function as a result of disturbance. We present evidence for a third response: resistance. We examined microbial community response to perturbation caused by nutrient enrichment in salt marsh sediments using deep pyrosequencing of 16S rRNA and functional gene microarrays targeting the nirS gene. Composition of the microbial community, as demonstrated by both genes, was unaffected by significant variations in external nutrient supply, despite demonstrable and diverse nutrient–induced changes in many aspects of marsh ecology. The lack of response to external forcing demonstrates a remarkable uncoupling between microbial composition and ecosystem-level biogeochemical processes and suggests that sediment microbial communities are able to resist some forms of perturbation.Funding for this research came from NSF(DEB-0717155 to JEH, DBI-0400819 to JLB). Support for the sequencing facility came from NIH and NSF (NIH/NIEHS-P50-ES012742-01 and NSF/OCE 0430724-J Stegeman PI to HGM and MLS, and WM Keck Foundation to MLS). Salary support provided from Princeton University Council on Science and Technology to JLB. Support for development of the functional gene microarray provided by NSF/OCE99-081482 to BBW. The Plum Island fertilization experiment was funded by NSF (DEB 0213767 and DEB 0816963)
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