219 research outputs found

    Isocitrate Dehydrogenase Mutant Grade II and III Glial Neoplasms

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    Mutations in isocitrate dehydrogenase (IDH) 1 or IDH2 occur in the majority of adult low-grade gliomas and, less commonly, in cholangiocarcinoma, chondrosarcoma, acute myeloid leukemia, and other human malignancies. Cancer-associated mutations alter the function of the enzyme, resulting in production of R(-)-2-hydroxyglutarate (R-2-HG) and broad epigenetic dysregulation. Small molecule IDH inhibitors have received regulatory approval for the treatment of IDH mutant (mIDH) leukemia and are under development for the treatment of mIDH solid tumors. This article provides a current view of IDH mutant adult astrocytic and oligodendroglial tumors, including their clinical presentation and treatment, and discusses novel approaches and challenges toward improving the treatment of these tumors

    Internal Friction of Amorphous Silicon in a Magnetic Field

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    The internal friction of e-beam amorphous silicon was measured in a magnetic field between 0 and 6 T, from 1.5-20 K, and was found to be independent of the field to better than 8%. It is concluded that the low energy excitations observed in this experiment are predominantly atomic in nature.Comment: 4 pages, 4 figures, REVTe

    Identification of asteroid genera with species capable of larval cloning

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    Asexual reproduction in larvae, larval cloning, is a recently recognized component of the complex life histories of asteroids. We compare DNA sequences of mitochondrial tRNA genes (Ala, Leu, Asn, Pro and Gln) from larvae in the process of cloning collected in the field with sequences from adults of known species in order to identify asteroid taxa capable of cloning. Neighbor-joining analysis identified four distinct groups of larvae, each having no, or very little, sequence divergence (p distances ranging from 0.00000 to 0.02589); thus, we conclude that each larval group most likely represents a single species. These field-collected larvae cannot be identified to species with certainty, but the close assemblage of known taxa with the four larval groups indicates generic or familial identity. We can assign two of the larval groups discerned here to the genera Luidia and Oreaster and another two to the family Ophidiasteridae. This study is the first to identify field-collected cloning asteroid larvae, and provides evidence that larval cloning is phylogenetically widespread within the Asteroidea. Additionally, we note that cloning occurs regularly and in multiple ways within species that are capable of cloning, emphasizing the need for further investigation of the role of larval cloning in the ecology and evolution of asteroids

    Rapid Artefact Removal and H&E-Stained Tissue Segmentation

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    We present an innovative method for rapidly segmenting hematoxylin and eosin (H&E)-stained tissue in whole-slide images (WSIs) that eliminates a wide range of undesirable artefacts such as pen marks and scanning artefacts. Our method involves taking a single-channel representation of a lowmagnification RGB overview of the WSI in which the pixel values are bimodally distributed suchthat H&E-stained tissue is easily distinguished from both background and a wide variety of artefacts. We demonstrate our method on 30 WSIs prepared from a wide range of institutions and WSI digital scanners, each containing substantial artefacts, and compare it to segmentations provided by Otsu thresholding and Histolab tissue segmentation and pen filtering tools. We found that our methodsegmented the tissue and fully removed all artefacts in 29 out of 30 WSIs, whereas Otsu thresholding failed to remove any artefacts, and the Histolab pen filtering tools only partially removed the pen marks. The beauty of our approach lies in its simplicity: manipulating RGB colour space and using Otsu thresholding allows for the segmentation of H&E-stained tissue and the rapid removal ofartefacts without the need for machine learning or parameter tuning

    Cross section of the ppK+Σ+npp\to K^+\Sigma^+n reaction close to threshold

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    We have measured inclusive data on K+K^+-meson production in pppp collisions at COSY J\"ulich close to the hyperon production threshold and determined the hyperon-nucleon invariant mass spectra. The spectra were decomposed into three parts: Λp\Lambda p, Σ0p\Sigma^0p and Σ+n\Sigma^+n. The cross section for the Σ+n\Sigma^+n channel was found to be much smaller than a previous measurement in that excess energy region. The data together with previous results at higher energies are compatible with a phase space dependence.Comment: accepted by Phys. lett. B some typos correcte

    Measurement of p + d -> 3He + eta in S(11) Resonance

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    We have measured the reaction p + d -> 3He + eta at a proton beam energy of 980 MeV, which is 88.5 MeV above threshold using the new ``germanium wall'' detector system. A missing--mass resolution of the detector system of 2.6% was achieved. The angular distribution of the meson is forward peaked. We found a total cross section of (573 +- 83(stat.) +- 69(syst.))nb. The excitation function for the present reaction is described by a Breit Wigner form with parameters from photoproduction.Comment: 8 pages, 2 figures, corrected typos in heade

    Detailed comparison of the pp -> \pi^+pn and pp -> \pi^+d reactions at 951 MeV

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    The positively charged pions produced in proton-proton collisions at a beam momentum of 1640 MeV/c were measured in the forward direction with a high resolution magnetic spectrograph. The missing mass distribution shows the bound state (deuteron) clearly separated from the pnpn continuum. Despite the very good resolution, there is no evidence for any significant production of the pnpn system in the spin-singlet state. However, the σ(ppπ+pn)/σ(ppπ+d)\sigma(pp\to \pi^+pn)/\sigma(pp\to \pi^+d) cross section ratio is about twice as large as that predicted from SS-wave final-state-interaction theory and it is suggested that this is due to DD-state effects in the pnpn system.Comment: 8 pages, 3 figure

    Mapping of hormones and cortisol responses in patients after Lyme neuroborreliosis

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    <p>Abstract</p> <p>Background</p> <p>Persistent symptoms after treatment for neuroborreliosis are common for reasons mainly unknown. These symptoms are often unspecific and could be caused by dysfunctions in endocrine systems, an issue that has not been previously addressed systematically. We therefore mapped hormone levels in patients with previous confirmed Lyme neuroborreliosis of different outcomes and compared them with a healthy control group.</p> <p>Methods</p> <p>Twenty patients of a retrospective cohort of patients treated for definite Lyme neuroborreliosis were recruited 2.3 to 3.7 years (median 2.7) after diagnosis, together with 23 healthy controls. Lyme neuroborreliosis patients were stratified into two groups according to a symptom/sign score. All participants underwent anthropometric and physiological investigation as well as an extensive biochemical endocrine investigation including a short high-dose adrenocorticotropic hormone stimulation (Synacthen<sup>®</sup>) test. In addition to hormonal status, we also examined electrolytes, 25-hydroxy-vitamin D and interleukin-6.</p> <p>Results</p> <p>Eight patients (40%) had pronounced symptoms 2-3 years after treatment. This group had a higher cortisol response to synacthen as compared with both controls and the Lyme neuroborreliosis patients without remaining symptoms (p < 0.001 for both comparisons). No other significant differences in the various baseline biochemical parameters, anthropometric or physiological data could be detected across groups.</p> <p>Conclusions</p> <p>Apart from a positive association between the occurrence of long-lasting complaints after Lyme neuroborreliosis and cortisol response to synacthen, no corticotropic insufficiency or other serious hormonal dysfunction was found to be associated with remaining symptoms after treatment for Lyme neuroborreliosis.</p
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