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Caryn S. Ross-Innes Irene Debiram-Beecham Maria O'Donovan Elaine Walker Sibu Varghese Pierre Lao-Sirieix Laurence Lovat Michael Griffin Krish Ragunath Rehan Haidry Sarmed S. Sami Philip Kaye Marco Novelli Babett Disep Richard Ostler Benoit Aigret Bernard V. North Pradeep Bhandari Adam Haycock Danielle Morris Stephen Attwood Anjan Dhar Colin Rees Matthew D. D. Rutter Peter D. Sasieni Rebecca C. Fitzgerald 《PLoS medicine》2015,12(1)
BackgroundBarrett''s esophagus (BE) is a commonly undiagnosed condition that predisposes to esophageal adenocarcinoma. Routine endoscopic screening for BE is not recommended because of the burden this would impose on the health care system. The objective of this study was to determine whether a novel approach using a minimally invasive cell sampling device, the Cytosponge, coupled with immunohistochemical staining for the biomarker Trefoil Factor 3 (TFF3), could be used to identify patients who warrant endoscopy to diagnose BE.ConclusionsThe Cytosponge-TFF3 test is safe and acceptable, and has accuracy comparable to other screening tests. This test may be a simple and inexpensive approach to identify patients with reflux symptoms who warrant endoscopy to diagnose BE. 相似文献
65.
Lori Newman Jane Rowley Stephen Vander Hoorn Nalinka Saman Wijesooriya Magnus Unemo Nicola Low Gretchen Stevens Sami Gottlieb James Kiarie Marleen Temmerman 《PloS one》2015,10(12)
Background
Quantifying sexually transmitted infection (STI) prevalence and incidence is important for planning interventions and advocating for resources. The World Health Organization (WHO) periodically estimates global and regional prevalence and incidence of four curable STIs: chlamydia, gonorrhoea, trichomoniasis and syphilis.Methods and Findings
WHO’s 2012 estimates were based upon literature reviews of prevalence data from 2005 through 2012 among general populations for genitourinary infection with chlamydia, gonorrhoea, and trichomoniasis, and nationally reported data on syphilis seroprevalence among antenatal care attendees. Data were standardized for laboratory test type, geography, age, and high risk subpopulations, and combined using a Bayesian meta-analytic approach. Regional incidence estimates were generated from prevalence estimates by adjusting for average duration of infection. In 2012, among women aged 15–49 years, the estimated global prevalence of chlamydia was 4.2% (95% uncertainty interval (UI): 3.7–4.7%), gonorrhoea 0.8% (0.6–1.0%), trichomoniasis 5.0% (4.0–6.4%), and syphilis 0.5% (0.4–0.6%); among men, estimated chlamydia prevalence was 2.7% (2.0–3.6%), gonorrhoea 0.6% (0.4–0.9%), trichomoniasis 0.6% (0.4–0.8%), and syphilis 0.48% (0.3–0.7%). These figures correspond to an estimated 131 million new cases of chlamydia (100–166 million), 78 million of gonorrhoea (53–110 million), 143 million of trichomoniasis (98–202 million), and 6 million of syphilis (4–8 million). Prevalence and incidence estimates varied by region and sex.Conclusions
Estimates of the global prevalence and incidence of chlamydia, gonorrhoea, trichomoniasis, and syphilis in adult women and men remain high, with nearly one million new infections with curable STI each day. The estimates highlight the urgent need for the public health community to ensure that well-recognized effective interventions for STI prevention, screening, diagnosis, and treatment are made more widely available. Improved estimation methods are needed to allow use of more varied data and generation of estimates at the national level. 相似文献66.
There are currently only a few theoretical studies on convective heat transfer in polymer nanocomposites. In this paper, the unsteady incompressible flow of a polymer nanocomposite represented by an Oldroyd-B nanofluid along a stretching sheet is investigated. Recent studies have assumed that the nanoparticle fraction can be actively controlled on the boundary, similar to the temperature. However, in practice, such control presents significant challenges and in this study the nanoparticle flux at the boundary surface is assumed to be zero. We have used a relatively novel numerical scheme; the spectral relaxation method to solve the momentum, heat and mass transport equations. The accuracy of the solutions has been determined by benchmarking the results against the quasilinearisation method. We have conducted a parametric study to determine the influence of the fluid parameters on the heat and mass transfer coefficients. 相似文献
67.
ZmMYB31 directly represses maize lignin genes and redirects the phenylpropanoid metabolic flux 总被引:4,自引:0,他引:4
Fornalé S Shi X Chai C Encina A Irar S Capellades M Fuguet E Torres JL Rovira P Puigdomènech P Rigau J Grotewold E Gray J Caparrós-Ruiz D 《The Plant journal : for cell and molecular biology》2010,64(4):633-644
Few regulators of phenylpropanoids have been identified in monocots having potential as biofuel crops. Here we demonstrate the role of the maize (Zea mays) R2R3-MYB factor ZmMYB31 in the control of the phenylpropanoid pathway. We determined its in vitro consensus DNA-binding sequence as ACC(T)/(A) ACC, and chromatin immunoprecipitation (ChIP) established that it interacts with two lignin gene promoters in vivo. To explore the potential of ZmMYB31 as a regulator of phenylpropanoids in other plants, its role in the regulation of the phenylpropanoid pathway was further investigated in Arabidopsis thaliana. ZmMYB31 downregulates several genes involved in the synthesis of monolignols and transgenic plants are dwarf and show a significantly reduced lignin content with unaltered polymer composition. We demonstrate that these changes increase cell wall degradability of the transgenic plants. In addition, ZmMYB31 represses the synthesis of sinapoylmalate, resulting in plants that are more sensitive to UV irradiation, and induces several stress-related proteins. Our results suggest that, as an indirect effect of repression of lignin biosynthesis, transgenic plants redirect carbon flux towards the biosynthesis of anthocyanins. Thus, ZmMYB31 can be considered a good candidate for the manipulation of lignin biosynthesis in biotechnological applications. 相似文献
68.
Adam S. Ptolemy Emma Tzioumis Arjun Thomke Sami Rifai Mark Kellogg 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(3-4):409-416
Targeted analyses of clinically relevant metabolites in human biofluids often require extensive sample preparation (e.g., desalting, protein removal and/or preconcentration) prior to quantitation. In this report, a single ultra-centrifugation based sample pretreatment combined with a designed liquid chromatography–tandem mass spectrometry (LC–MS/MS) protocol provides selective quantification of 3,7-dimethylxanthine (theobromine) and 1,3,7-trimethylxanthine (caffeine) in human saliva, plasma and urine samples. The optimized chromatography permitted elution of both analytes within 1.3 min of the applied gradient. Positive-mode electrospray ionization and a triple quadruple MS/MS instrument operated in multiple reaction mode were used for detection. 13C3 isotopically labeled caffeine was included as an internal standard to improve accuracy and precision. Implementing a 20-fold dilution of the isolated low MW biofluid fraction prior to injection effectively minimized the deleterious contributions of all three matrices to quantitation. The assay was linear over a 160-fold concentration range from 2.5 to 400 μmol L?1 for both theobromine (average R2 0.9968) and caffeine (average R2 0.9997) respectively. Analyte peak area variations for 2.5 μmol L?1 caffeine and theobromine in saliva, plasma and urine ranged from 5 and 10% (intra-day, N = 10) to 9 and 13% (inter-day, N = 25) respectively. The intra- and inter-day precision of theobromine and caffeine elution times were 3 and <1% for all biofluids and concentrations tested. Recoveries for caffeine and theobromine ranged from 114 to 118% and 99 to 105% at concentration levels of 10 and 300 μmol L?1. This validated protocol also permitted the relative saliva, plasma and urine distribution of both theobromine and caffeine to be quantified following a cocoa intervention. 相似文献
69.
Jukka Bisi Tuija Liukkonen Sakari Mykrä Mari Pohja-Mykrä Sami Kurki 《European Journal of Wildlife Research》2010,56(5):771-779
This article focuses on the roots of the Finnish wolf conflict by using stakeholder evaluations of the wolf as a tool. The
recent growth of the wolf population has highlighted stakeholders’ contradictory objectives and revealed a conflict between
the two main stakeholders, conservationists and hunters, in wolf management. The question of hunting emerges as the core of
the conflict. The negative evaluation of the wolf by hunters reflects a competitive situation, which is typical of the historical
development of wolf management in Finland. In areas with the most abundant wolf populations, hunters view the wolf most negatively.
This study clearly demonstrates that the Finnish wolf conflict is rooted in the values of modern society and carries a long
historical, practical and ecological background in which humans and wolves compete over resources, mainly the moose. The conflict
between hunters and conservationists in wolf management is connected to the appreciation of moose as game and stems from competition
between humans and wolves over their prey and the historical presence or absence of the wolf. 相似文献
70.
Progressive multifocal encephalopathy (PML) is a fatal demyelinating disease of the central nervous system (CNS), caused by the lytic infection of oligodendrocytes by a human polyomavirus, JC virus (JCV). PML is rare disease but mostly develops in patients with underlying immunosuppressive conditions, including Hodgkin's lymphoma, lymphoproliferative diseases, in those undergoing antineoplastic therapy and AIDS. However, consistent with the occurrence of PML under immunocompromised conditions, this disease seems to be also steadily increasing among autoimmune disease patients (multiple sclerosis and Crohn's disease), who are treated with antibody-based regimens (natalizumab, efalizumab and rituximab). This unexpected occurrence of the disease among such a patient population reconfirms the existence of a strong link between the underlying immunosuppressive conditions and development of PML. These recent observations have generated a new interest among investigators to further examine the unique biology of JCV. 相似文献