Background Chest CT is used to assess the severity of lung involvement in COVID-19 pneumonia. Purpose To determine the change in chest CT findings associated with COVID-19 pneumonia from initial di...

One year after COVID-19 diagnosis, chest CT scans showed persistent abnormalities in 53 of 209 adult study participants (25%). Background The chest CT manifestations of COVID-19 from hospitalization to convalescence after 1 year are unknown. Purpose To assess chest CT manifestations of COVID-19 up to 1 year after symptom o...

Plasmodium falciparum genotyping has recently undergone a revolution, and genome‐wide genotype datasets are now being collected for large numbers of parasite isolates. By contrast, phenotyping technologies have lagged behind, with few high throughput phenotyping platforms available. Invasion of human erythrocytes by Plasmodium falciparum is a phenotype of particular interest because of its central role in parasite development. Invasion is a variable phenotype influenced by natural genetic variation in both the parasite and host and is governed by multiple overlapping and in some instances redundant parasite–erythrocyte interactions. To facilitate the scale‐up of erythrocyte invasion phenotyping, we have developed a novel platform based on two‐color flow cytometry that distinguishes parasite invasion from parasite growth. Target cells that had one or more receptors removed using enzymatic treatment were prelabeled with intracellular dyes CFDA‐SE or DDAO‐SE, incubated with P. falciparum parasites, and parasites that had invaded either labeled or unlabeled cells were detected with fluorescent DNA‐intercalating dyes Hoechst 33342 or SYBR Green I. Neither cell label interfered with erythrocyte invasion, and the combination of cell and parasite dyes recapitulated known invasion phenotypes for three standard laboratory strains. Three different dye combinations with minimal overlap have been validated, meaning the same assay can be adapted to instruments harboring several different combinations of laser lines. The assay is sensitive, operates in a 96‐well format, and can be used to quantitate the impact of natural or experimental genetic variation on erythrocyte invasion efficiency. © 2010 International Society for Advancement of Cytometry

For over fifty years, the pathogenesis of May-Thurner syndrome (MTS) has been associated with chronic left common iliac vein compression resulting in the formation of intraluminal, permanent obstructive lesions. However, despite this association, the mechanism by which compression produces these lesions is unknown. Diagnostic accuracy of MTS is critical since it often afflicts young patients requiring endovascular management. This review will focus on the historical, embryological and evolutionary description of MTS and examine its development, diagnosis, clinical management and potential diagnostic errors.

Purpose: Dynamic magnetic resonance spectroscopic imaging of hyperpolarized ¹³C‐labeled cell substrates has enabled the investigation of tissue metabolism in vivo. Currently observation of these hyperpolarized substrates is limited mainly to ¹³C detection. We describe here an imaging pulse sequence that enables proton observation by using polarization transfer from the hyperpolarized ¹³C nucleus to spin‐coupled protons.Methods: The pulse sequence transfers ¹³C hyperpolarization to ¹H using a modified reverse insensitive nuclei enhanced by polarization transfer (INEPT) sequence that acquires a fully refocused echo. The resulting hyperpolarized ¹H signal is acquired using a 2D echo‐planar trajectory. The efficiency of polarization transfer was investigated using simulations with and without T₁ and T₂ relaxation of both the ¹H and ¹³C nuclei.Results: Simulations showed that ¹H detection of the hyperpolarized ¹³C nucleus in lactate should increase significantly the signal‐to‐noise ratio when compared with direct ¹³C detection at 3T. However the advantage of ¹H detection is expected to disappear at higher fields. Dynamic ¹H images of hyperpolarized [1‐¹³C]lactate, with a spatial resolution of 1.25 × 1.25 mm², were acquired from a phantom injected with hyperpolarized [1‐¹³C]lactate and from tumors in vivo following injection of hyperpolarized [1‐¹³C]pyruvate.Conclusions: The sequence allows ¹H imaging of hyperpolarized ¹³C‐labeled substrates in vivo. Magn Reson Med 79:741–747, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.