A new cylindrical detector for borehole muon radiography Saracino, G.; Ambrosino, F.; Anastasio, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
March 2023, 2023-03-00, Letnik:
1048
Journal Article
Recenzirano
Muons of cosmic origin have a great capability to penetrate through matter. This property is exploited in muon radiography, also known as muography, a technique which allows to highlight the presence ...of discontinuities of the mass density in the subsoil such as cavities, tunnels or rock masses. A detector of cylindrical geometry, optimized for borehole studies and with a diameter of 24 cm, was developed and tested . The scintillation light is read out by 384 Silicon Photomultipliers, directly coupled to the bars. The front-end and acquisition electronics, entirely housed inside the detector, are based on the EASIROC chip and are characterized by limited energy consumption (about 30 W for the entire detector). The detector has been designed in such a way as to simplify its construction as much as possible for its eventual mass production. In this article some details concerning the construction and preliminary results of measurements conducted in the Mt Echia (Naples, Italy) underground are presented.
Tumors are composed of phenotypically heterogeneous cancer cells that often resemble various differentiation states of their lineage of origin. Within this hierarchy, it is thought that an immature ...subpopulation of tumor-propagating cancer stem cells (CSCs) differentiates into non-tumorigenic progeny, providing a rationale for therapeutic strategies that specifically eradicate CSCs or induce their differentiation. The clinical success of these approaches depends on CSC differentiation being unidirectional rather than reversible, yet this question remains unresolved even in prototypically hierarchical malignancies, such as acute myeloid leukemia (AML). Here, we show in murine and human models of AML that, upon perturbation of endogenous expression of the lineage-determining transcription factor PU.1 or withdrawal of established differentiation therapies, some mature leukemia cells can de-differentiate and reacquire clonogenic and leukemogenic properties. Our results reveal plasticity of CSC maturation in AML, highlighting the need to therapeutically eradicate cancer cells across a range of differentiation states.
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•Reversible PU.1 knockdown provides a genetic model of AML differentiation therapy•Mature AML-derived cells can revert to a leukemogenic state upon PU.1 suppression•Mouse and human APL cells can regain clonogenicity after ATRA-induced differentiation
Intratumoral phenotypic heterogeneity in acute myeloid leukemia (AML) and many other cancers is thought to follow a hierarchical cancer stem cell model. Dickins and colleagues show here that mature, non-leukemogenic AML cells can reacquire leukemia-initiating activity and promote disease progression through de-differentiation.
The B lymphocyte-induced maturation protein 1 (Blimp-1) transcriptional repressor is required for terminal differentiation of B lymphocytes. Here we document a function for Blimp-1 in the T cell ...lineage. Blimp-1-deficient thymocytes showed decreased survival and Blimp-1-deficient mice had more peripheral effector T cells. Mice lacking Blimp-1 developed severe colitis as early as 6 weeks of age, and Blimp-1-deficient regulatory T cells were defective in blocking the development of colitis. Blimp-1 mRNA expression increased substantially in response to T cell receptor stimulation. Compared with wild-type CD4(+) T cells, Blimp-1-deficient CD4(+) T cells proliferated more and produced excess interleukin 2 and interferon-gamma but reduced interleukin 10 after T cell receptor stimulation. These results emphasize a crucial function for Blimp-1 in controlling T cell homeostasis and activation.
A realistic body representation needs to be constantly updated. In case of physiological modifications, body representations integrate information coming from different sensory sources, including the ...sense of touch. Previous studies described transient modifications of these representations following illusory distortions. In this single case study, we documented the changes occurred in lower-level, primary somatosensory, and higher-level representations, in a case of upper arms elongation.
We explored effects of arm lengthening on primary tactile perception (sensitivity and acuity), an implicit perceptual measure of body size (tactile distance judgement), body image (Daurat-Hmelijak test), and peri-personal space representation (audio-tactile interaction task).
We show that patient's arm representation was changed after surgery. Specifically, we observed significant changes on tactile distance judgments, body image test and audio-tactile interaction task; also even though no changes were found on primary tactile perception a significant modification emerged in tactile acuity.
These findings are in line with evidence of cortical reorganization after arm elongation. They also support the view that the body representation of achondroplasics are modified after body-size reconstruction, and became similar to that of healthy controls.
Emotional perception has been extensively studied, but only a few studies have investigated the brain activity preceding exposure to emotional stimuli, especially when they are triggered by the ...subject himself. Here, we sought to investigate the emotional expectancy by means of movement related cortical potentials (MRCPs) in a self-paced task, in which the subjects begin the affective experience by pressing a key. In this experiment, participants had to alternatively press two keys to concomitantly display positive, negative, neutral, and scrambled images extracted from the International Affective Pictures System (IAPS). Each key press corresponded to a specific emotional category, and the experimenter communicated the coupling before each trial so that the subjects always knew the valence of the forthcoming picture. The main results of the present study included a bilateral positive activity in prefrontal areas during expectancy of more arousing pictures (positive and negative) and an early and sustained positivity over occipital areas, especially during negative expectancy. In addition, we observed more pronounced and anteriorly distributed Late Positive Potential (LPPs) components in the emotional conditions. In conclusion, these results show that emotional expectancy can influence brain activity in both motor preparation and stimulus perception, suggesting enhanced pre-processing in the to-be-stimulated areas. We propose that before a predictable emotional stimulus, both appetitive and defensive motivational systems act to facilitate the forthcoming processing of survival-relevant contents by means of an enhancement of attention toward more arousing pictures.
Muon radiography, also known as muography, is an imaging technique that provides information on the mass density distribution inside large objects. Muons are naturally produced in the interactions of ...cosmic rays in the Earth’s atmosphere. The physical process exploited by muography is the attenuation of the muon flux, that depends on the thickness and density of matter that muons cross in the course of their trajectory. A particle detector with tracking capability allows the measurement of the muons flux as a function of the muon direction. The comparison of the measured muon flux with the expected one gives information on the distribution of the density of matter, in particular, on the presence of cavities. In this article, the measurement performed at Mt. Echia in Naples (Saracino 2017 Sci. Rep. 7, 1181. (doi:10.1038/s41598-017-01277-3)), will be discussed as a practical example of the possible application of muography in archaeology and civil engineering.
This article is part of the Theo Murphy meeting issue ‘Cosmic-ray muography’.
•Increased levels of interleukin 1 were found in the bone marrow fluid of TpoTg mice, whereas levels were lowered in Mpl−/− mice.•A proinflammatory microenvironment promoted Eμ-myc lymphoma ...progression in TpoTg mice with high megakaryocyte and thrombopoietin levels.
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Platelets have been shown to enhance the survival of lymphoma cell lines. However, it remains unclear whether they play a role in lymphoma. Here, we investigated the potential role of platelets and/or megakaryocytes in the progression of Eμ-myc lymphoma. Eμ-myc tumor cells were transplanted into recipient wild-type (WT) control, Mpl−/−, or TpoTg mice, which exhibited normal, low, and high platelet and megakaryocyte counts, respectively. TpoTg mice that underwent transplantation exhibited enhanced lymphoma progression with increased white blood cell (WBC) counts, spleen and lymph node weights, and enhanced liver infiltration when compared with WT mice. Conversely, tumor-bearing Mpl−/− mice had reduced WBC counts, lymph node weights, and less liver infiltration than WT mice. Using an Mpl-deficient thrombocytopenic immunocompromised mouse model, our results were confirmed using the human non-Hodgkin lymphoma GRANTA cell line. Although we found that platelets and platelet-released molecules supported Eμ-myc tumor cell survival in vitro, pharmacological inhibition of platelet function or anticoagulation in WT mice transplanted with Eμ-myc did not improve disease outcome. Furthermore, transient platelet depletion or sustained Bcl-xL–dependent thrombocytopenia did not alter lymphoma progression. Cytokine analysis of the bone marrow fluid microenvironment revealed increased levels of the proinflammatory molecule interleukin 1 in TpoTg mice, whereas these levels were lower in Mpl−/− mice. Moreover, RNA sequencing of blood-resident Eμ-myc lymphoma cells from TpoTg and WT mice after tumor transplantation revealed the upregulation of hallmark gene sets associated with an inflammatory response in TpoTg mice. We propose that the proinflammatory microenvironment in TpoTg mice promotes lymphoma progression.
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