129 research outputs found

    CT Scanning and Dental Implant

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    Analyses bactériologiques et cellulaires des échantillons de lait chez des chèvres après sélection divergente sur la résistance aux mammites

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    La concentration des cellules somatiques (CCS) est un critère très utilisé pour évaluer le statut infectieux de la mamelle chez la chèvre. Grace à l’analyse en cytométrie en flux, celle-ci a été décomposée en concentrations de neutrophiles (vivants et morts), lymphocytes, macrophages dans le but d’étudier la réponse inflammatoire locale chez deux lignées de chèvres génétiquement divergentes sur le critère de la CCS. L’objectif de cette étude était de décrire l’évolution au cours de la lactation de la CCS en fonction du statut bactériologique. Les infections mammaires chez les chèvres de la lignée résistante sont moins fréquentes et avec des titres bactériens plus faibles d’après les données acquises par les méthodes conventionnelle et moléculaire. De plus, leurs réponses inflammatoire et immunitaire locales semblent plus efficaces lors d’infection

    Overcoming the electroluminescence efficiency limitations of perovskite light-emitting diodes.

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    Organic-inorganic hybrid perovskites are emerging low-cost emitters with very high color purity, but their low luminescent efficiency is a critical drawback. We boosted the current efficiency (CE) of perovskite light-emitting diodes with a simple bilayer structure to 42.9 candela per ampere, similar to the CE of phosphorescent organic light-emitting diodes, with two modifications: We prevented the formation of metallic lead (Pb) atoms that cause strong exciton quenching through a small increase in methylammonium bromide (MABr) molar proportion, and we spatially confined the exciton in uniform MAPbBr3 nanograins (average diameter = 99.7 nanometers) formed by a nanocrystal pinning process and concomitant reduction of exciton diffusion length to 67 nanometers. These changes caused substantial increases in steady-state photoluminescence intensity and efficiency of MAPbBr3 nanograin layers.This work was partially supported by Samsung Research Funding Center of Samsung Electronics under Project Number SRFC-MA-1402-07. A.S. was partially supported by the Engineering and Physical Sciences Research Council (UK).This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by the American Association for the Advancement of Science

    Human AQP5 Plays a Role in the Progression of Chronic Myelogenous Leukemia (CML)

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    Aquaporins (AQPs) have previously been associated with increased expression in solid tumors. However, its expression in hematologic malignancies including CML has not been described yet. Here, we report the expression of AQP5 in CML cells by RT-PCR and immunohistochemistry. While normal bone marrow biopsy samples (n = 5) showed no expression of AQP5, 32% of CML patient samples (n = 41) demonstrated AQP5 expression. In addition, AQP5 expression level increased with the emergence of imatinib mesylate resistance in paired samples (p = 0.047). We have found that the overexpression of AQP5 in K562 cells resulted in increased cell proliferation. In addition, small interfering RNA (siRNA) targeting AQP5 reduced the cell proliferation rate in both K562 and LAMA84 CML cells. Moreover, by immunoblotting and flow cytometry, we show that phosphorylation of BCR-ABL1 is increased in AQP5-overexpressing CML cells and decreased in AQP5 siRNA-treated CML cells. Interestingly, caspase9 activity increased in AQP5 siRNA-treated cells. Finally, FISH showed no evidence of AQP5 gene amplification in CML from bone marrow. In summary, we report for the first time that AQP5 is overexpressed in CML cells and plays a role in promoting cell proliferation and inhibiting apoptosis. Furthermore, our findings may provide the basis for a novel CML therapy targeting AQP5

    Broad humoral and cellular immunity elicited by one-dose mRNA vaccination 18 months after SARS-CoV-2 infection

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    Practical guidance is needed regarding the vaccination of coronavirus disease 2019 (COVID-19) convalescent individuals in resource-limited countries. It includes the number of vaccine doses that should be given to unvaccinated patients who experienced COVID-19 early in the pandemic. We recruited COVID-19 convalescent individuals who received one or two doses of an mRNA vaccine within 6 or around 18 months after a diagnosis of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection. Their samples were assessed for IgG-binding or neutralizing activity and cell-mediated immune responses against SARS-CoV-2 wild-type and variants of concern. A total of 43 COVID-19 convalescent individuals were analyzed in the present study. The results showed that humoral and cellular immune responses against SARS-CoV-2 wild-type and variants of concern, including the Omicron variant, were comparable among patients vaccinated within 6 versus around 18 months. A second dose of vaccine did not significantly increase immune responses. One dose of mRNA vaccine should be considered sufficient to elicit a broad immune response even around 18 months after a COVID-19 diagnosis.This work was supported in part by the Bio & Medical Technology Develop‑ ment Program of the National Research Foundation (NRF) & funded by the Korean government (MSIT) (2021M3A9I2080496, to H.-R. Kim & W. B. Park), the Creative-Pioneering Researchers Program through Seoul National University (to C.-H. Lee), and the Seoul National University Hospital Research Fund (112021-5050 to P. G. Choe and 800-20220110 to C.-H. Lee)

    Ocular Manifestations of Acquired Immunodeficiency Syndrome in Korea

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    The clinical features of HIV/AIDS-related ocular manifestations in Korean patients were investigated in this study. Data on 200 consecutive Korean patients diagnosed with AIDS who visited the Seoul National University Hospital from January 2003 to June 2008 were reviewed. Fifty-seven patients (28.5%) had ocular manifestations, and they showed significantly lower CD4+ T cell count than patients without ocular manifestations. Among them, 23 (40.3%) patients showed retinal microvasculopathy, and 22 (38.5%) patients showed cytomegalovirus (CMV) retinitis. Other manifestations included retinal vein occlusion (n = 4), herpes zoster ophthalmicus (n = 4), syphilitic uveitis (n = 2), acute retinal necrosis (n = 1), and progressive outer retinal necrosis (n = 1). The mean CD4+ lymphocyte counts of the patients with retinal microvasculopathy and cytomegalovirus retinitis were 108.5 cells/µL and 69.4 cells/µL, respectively. In conclusion, ocular manifestations including CMV retinitis are common complications in Korean patients with AIDS even in the era of highly active anti-retroviral therapy. Compared to previous reports in western countries, prevalence of CMV retinitis is relatively low and CD4+ lymphocytes count at the time of diagnosis is relatively high

    A Nuclear Localization of the Infectious Haematopoietic Necrosis Virus NV Protein Is Necessary for Optimal Viral Growth

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    The nonvirion (NV) protein of infectious hematopoietic necrosis virus (IHNV) has been previously reported to be essential for efficient growth and pathogenicity of IHNV. However, little is known about the mechanism by which the NV supports the viral growth. In this study, cellular localization of NV and its role in IHNV growth in host cells was investigated. Through transient transfection in RTG-2 cells of NV fused to green fluorescent protein (GFP), a nuclear localization of NV was demonstrated. Deletion analyses showed that the 32EGDL35 residues were essential for nuclear localization of NV protein, and fusion of these 4 amino acids to GFP directed its transport to the nucleus. We generated a recombinant IHNV, rIHNV-NV-ΔEGDL in which the 32EGDL35 was deleted from the NV. rIHNVs with wild-type NV (rIHNV-NV) or with the NV gene replaced with GFP (rIHNV-ΔNV-GFP) were used as controls. RTG-2 cells infected with rIHNV-ΔNV-GFP and rIHNV-NV-ΔEGDL yielded 12- and 5-fold less infectious virion, respectively, than wild type rIHNV-infected cells at 48 h post-infection (p.i.). While treatment with poly I∶C at 24 h p.i. did not inhibit replication of wild-type rIHNVs, replication rates of rIHNV-ΔNV-GFP and rIHNV-NV-ΔEGDL were inhibited by poly I∶C. In addition, both rIHNV-ΔNV and rIHNV-NV-ΔEGDL induced higher levels of expressions of both IFN1 and Mx1 than wild-type rIHNV. These data suggest that the IHNV NV may support the growth of IHNV through inhibition of the INF system and the amino acid residues of 32EGDL35 responsible for nuclear localization are important for the inhibitory activity of NV

    New Era of Air Quality Monitoring from Space: Geostationary Environment Monitoring Spectrometer (GEMS)

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    GEMS will monitor air quality over Asia at unprecedented spatial and temporal resolution from GEO for the first time, providing column measurements of aerosol, ozone and their precursors (nitrogen dioxide, sulfur dioxide and formaldehyde). Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for launch in late 2019 - early 2020 to monitor Air Quality (AQ) at an unprecedented spatial and temporal resolution from a Geostationary Earth Orbit (GEO) for the first time. With the development of UV-visible spectrometers at sub-nm spectral resolution and sophisticated retrieval algorithms, estimates of the column amounts of atmospheric pollutants (O3, NO2, SO2, HCHO, CHOCHO and aerosols) can be obtained. To date, all the UV-visible satellite missions monitoring air quality have been in Low Earth orbit (LEO), allowing one to two observations per day. With UV-visible instruments on GEO platforms, the diurnal variations of these pollutants can now be determined. Details of the GEMS mission are presented, including instrumentation, scientific algorithms, predicted performance, and applications for air quality forecasts through data assimilation. GEMS will be onboard the GEO-KOMPSAT-2 satellite series, which also hosts the Advanced Meteorological Imager (AMI) and Geostationary Ocean Color Imager (GOCI)-2. These three instruments will provide synergistic science products to better understand air quality, meteorology, the long-range transport of air pollutants, emission source distributions, and chemical processes. Faster sampling rates at higher spatial resolution will increase the probability of finding cloud-free pixels, leading to more observations of aerosols and trace gases than is possible from LEO. GEMS will be joined by NASA's TEMPO and ESA's Sentinel-4 to form a GEO AQ satellite constellation in early 2020s, coordinated by the Committee on Earth Observation Satellites (CEOS)

    DIRECT CONTACT SHIELD OF LiMn2O4 ACTIVE MATERIAL FROM ELECTROLYTE

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    The spinel LiMn2O4 powders were prepared by sol–gel technique using lithium acetate (Li(CH3COO) · 2H2O) and manganese acetate (Mn(CH3COO)2 · 4H2O) as starting materials, citric acid as a chelating agent, and acrylamide as a gel formatting agent. In order to improve the electrochemical performance of lithium ion batteries and prevent structural disintegration from Mn dissolution generated by undesirable acid production, conductive agents were additionally coated on the surface of active material coated on pure aluminum foil as a current collector. Also, it was comparatively investigated using different conductive agents with different particle sizes as well as adopting the cells into the different thermal environments. The electrochemical performance of the Li/LiMn2O4 cells demonstrated that the spinel LiMn2O4 might be effectively shielded from acid, resulting in improved electrochemical capacity characteristics at room temperature as well as elevated temperature of 55°C.Lithium ion battery, cathode, LiMn2O4, Mn dissolution
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