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991.
Yu Winston Wang Soyoung Kang Altaz Khan Philip Q. Bao Jonathan T.C. Liu 《Biomedical optics express》2015,6(10):3714-3723
The biological investigation and detection of esophageal cancers could be facilitated with an endoscopic technology to screen for the molecular changes that precede and accompany the onset of cancer. Surface-enhanced Raman scattering (SERS) nanoparticles (NPs) have the potential to improve cancer detection and investigation through the sensitive and multiplexed detection of cell-surface biomarkers. Here, we demonstrate that the topical application and endoscopic imaging of a multiplexed cocktail of receptor-targeted SERS NPs enables the rapid detection of tumors in an orthotopic rat model of esophageal cancer. Antibody-conjugated SERS NPs were topically applied on the lumenal surface of the rat esophagus to target EGFR and HER2, and a miniature spectral endoscope featuring rotational scanning and axial pull-back was employed to comprehensively image the NPs bound on the lumen of the esophagus. Ratiometric analyses of specific vs. nonspecific binding enabled the visualization of tumor locations and the quantification of biomarker expression in agreement with immunohistochemistry and flow cytometry validation data.OCIS codes: (170.5660) Raman spectroscopy, (170.2150) Endoscopic imaging, (110.2350) Fiber optics imaging, (170.0170) Medical optics and biotechnology, (170.2680) Gastrointestinal, (160.4236) Nanomaterials 相似文献
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Johannes Wolf Jonathan I. Sperl Florian Schaff Markus Schüttler Andre Yaroshenko Irene Zanette Julia Herzen Franz Pfeiffer 《Biomedical optics express》2015,6(12):4812-4824
X-ray grating interferometry requires gratings with periods in the micrometer range and allows the acquisition of the dark-field contrast. The analyzer grating is designed to match the period of the interference pattern in order to translate it into a measurable intensity modulation. In this study, we explore the influence of a sample-induced mismatch between the interference pattern and the analyzer grating on the dark-field contrast. We propose a formula for the calculation of the signal due to a period mismatch and present estimations varying periods and detector pixel size. Furthermore, numerical simulations of the X-ray wave-front demonstrate that the wave-front curvature, described by the lens-term, e.g. behind a parabolic lens or edges of a sample can change the period of the interference pattern. Our results give a concrete explanation for the formation of a dark-field contrast from object edges and thus allow a better understanding of the dark-field signal obtained with a grating interferometer.OCIS codes: (110.7440) X-ray imaging, (340.7450) X-ray interferometry 相似文献
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A multicenter validation of recombinant β3 integrin–coupled beads to detect human platelet antigen‐1 alloantibodies in 498 cases of fetomaternal alloimmune thrombocytopenia 下载免费PDF全文
Winnie Chong Ernest Turro Paul Metcalfe Rizwan Yusuf Yves Mérieux Dominique Rigal Leendert Porcelijn Elly Huiskes Geoff Lucas Nina Bendukidze Ann Green Rita Fontão‐Wendel Anne Husebekk Jonathan Dixey Alan Guest Rosey Mushens Willem H. Ouwehand Cristina V. Navarrete 《Transfusion》2015,55(11):2742-2751
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Cibele Almeida Santos Renata Calhes Franco de Moura Roberta Delasta Lazzari Arislander Jonathan Lopes Dumont Luiz Alfredo Ferreira Braun Claudia Santos Oliveira 《Journal of Physical Therapy Science》2015,27(5):1617-1620
[Purpose] The aim of the present study was to perform a systematic review of the
literature on the scales and methods most often used for the evaluation of upper limb
function in individuals with cerebral palsy. [Materials and Methods] Searches were
conducted in the Medline, PEDro, Lilacs, Scielo, and PubMed databases. The following
inclusion criteria were used for the selection of articles: randomized controlled study,
evaluation of upper limb function in individuals with cerebral palsy, and publication
between 2006 and 2014. The methodological quality of the articles was evaluated using the
PEDro evidence scale. [Results] Five articles met the inclusion criteria and achieved 6
points or higher on the PEDro scale of methodological quality. [Conclusion] The studies
analyzed used different evaluation scales, but no consensus has been reached thus far on
which scale is the most appropriate. Thus, further studies are needed to establish an
adequate method for the evaluation of upper limb function in individuals with cerebral
palsy.Key words: Cerebral palsy, Scale function, Upper limbs 相似文献
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Marc-Antoine de La Vega Grazia Caleo Jonathan Audet Xiangguo Qiu Robert A. Kozak James I. Brooks Steven Kern Anja Wolz Armand Sprecher Jane Greig Kamalini Lokuge David K. Kargbo Brima Kargbo Antonino Di Caro Allen Grolla Darwyn Kobasa James E. Strong Giuseppe Ippolito Michel Van Herp Gary P. Kobinger 《The Journal of clinical investigation》2015,125(12):4421-4428
BACKGROUND. Ebola virus (EBOV) causes periodic outbreaks of life-threatening EBOV disease in Africa. Historically, these outbreaks have been relatively small and geographically contained; however, the magnitude of the EBOV outbreak that began in 2014 in West Africa has been unprecedented. The aim of this study was to describe the viral kinetics of EBOV during this outbreak and identify factors that contribute to outbreak progression.METHODS. From July to December 2014, one laboratory in Sierra Leone processed over 2,700 patient samples for EBOV detection by quantitative PCR (qPCR). Viremia was measured following patient admission. Age, sex, and approximate time of symptom onset were also recorded for each patient. The data was analyzed using various mathematical models to find trends of potential interest.RESULTS. The analysis revealed a significant difference (P = 2.7 × 10–77) between the initial viremia of survivors (4.02 log10 genome equivalents [GEQ]/ml) and nonsurvivors (6.18 log10 GEQ/ml). At the population level, patient viral loads were higher on average in July than in November, even when accounting for outcome and time since onset of symptoms. This decrease in viral loads temporally correlated with an increase in circulating EBOV-specific IgG antibodies among individuals who were suspected of being infected but shown to be negative for the virus by PCR.CONCLUSIONS. Our results indicate that initial viremia is associated with outcome of the individual and outbreak duration; therefore, care must be taken in planning clinical trials and interventions. Additional research in virus adaptation and the impacts of host factors on EBOV transmission and pathogenesis is needed. 相似文献