41 research outputs found

    Case of plasmablastic lymphoma of the sigmoid colon and literature review

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    Plasmablastic lymphoma (PBL) is a rare form of non-Hodgkin\u27s lymphoma that is associated with human immunodeficiency virus (HIV) infection. Although PBL is most commonly observed in the oral cavity of HIV-positive patients, it can also be observed at extra-oral sites in HIV-negative patients. This report represents an unusual case of HIV-negative PBL that occurred in the sigmoid colon. This patient had a history of systemic lupus erythematosus and an underlying immunosuppressive state from long term steroid therapy. The lymphoma cells were positive for CD138, kappa light chain restriction and Epstein-Barr virus and negative for CD20/L26, CD3, CD79a, UCHL1 (CD45RO) and cytokeratin (AE1/AE3). The patient died approximately 2 mo after the operation. In the present paper, we review cases of PBL of the colon in HIVnegative patients

    Detection of viral RNA in diverse body fluids in an SFTS patient with encephalopathy, gastrointestinal bleeding and pneumonia: a case report and literature review

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    BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that commonly has a lethal course caused by the tick-borne Huaiyangshan banyang virus [former SFTS virus (SFTSV)]. The viral load in various body fluids in SFTS patients and the best infection control measure for SFTS patients have not been fully established. CASE PRESENTATION: A 79-year-old man was bitten by a tick while working in the bamboo grove in Nagasaki Prefecture in the southwest part of Japan. Due to the occurrence of impaired consciousness, he was referred to Nagasaki University Hospital for treatment. The serum sample tested positive for SFTSV-RNA in the genome amplification assay, and he was diagnosed with SFTS. Furthermore, SFTSV-RNA was detected from the tick that had bitten the patient. He was treated with multimodal therapy, including platelet transfusion, antimicrobials, antifungals, steroids, and continuous hemodiafiltration. His respiration was assisted with mechanical ventilation. On day 5, taking the day on which he was hospitalized as day 0, serum SFTSV-RNA levels reached a peak and then decreased. However, the cerebrospinal fluid collected on day 13 was positive for SFTSV-RNA. In addition, although serum SFTSV-RNA levels decreased below the detectable level on day 16, he was diagnosed with pneumonia with computed tomography. SFTSV-RNA was detected in the bronchoalveolar lavage fluid on day 21. By day 31, he recovered consciousness completely. The pneumonia improved by day 51, but SFTSV-RNA in the sputum remained positive for approximately 4 months after disease onset. Strict countermeasures against droplet/contact infection were continuously conducted. CONCLUSIONS: Even when SFTSV genome levels become undetectable in the serum of SFTS patients in the convalescent phase, the virus genome remains in body fluids and tissues. It may be possible that body fluids such as respiratory excretions become a source of infection to others; thus, careful infection control management is needed

    硫黄を含むメタン水蒸気改質反応でのアルミナ担持白金触媒の炭素析出と活性点

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    Effect of sulfur poisoning on Pt/α-Al2O3 catalysts in steam methane reforming (SMR) was investigated using dimethyl sulfide (DMS). SMR with and without 10 ppm DMS addition was performed over 0.1-2.0 wt% Pt/α-Al2O3 catalysts. Catalyst deterioration occurred at an early stage, but not inactivation in the presence of DMS. Moreover, after the supply of DMS was stopped, the activity was completely restored. DMS in the reaction gas also caused severe sintering of the Pt particles and promoted carbon formation on the 1.0-2.0 wt% Pt catalysts. On the other hand, carbon formation did not occur on the 0.1 wt% Pt catalysts. The Pt sintering and carbon formation behaviors were independent of the SMR activity. These results suggest that three different active sites are formed on the Pt/α-Al2O3. The first is a SMR active site not affected by DMS. The second is an active site that loses activity due to DMS, but completely regenerates after the supply of DMS is stopped. The third is not an active site of SMR but where sintered Pt accelerates methane decomposition to produce carbon.メタン水蒸気改質(SMR)反応を0.1~2.0 wt% Pt/α-Al2O3触媒を用いて10 ppmのジメチルスルフィド(DMS)を含む条件と含まない条件で行った。DMSを含む場合は初期に劣化が生じるが失活には至らなかった。DMSの供給を停止すると活性は完全に元に戻った。DMSを含むガスの場合は1.0~2.0 wt% Pt/α-Al2O3触媒上のPtはシンタリングして炭素析出を促進した。このシンタリングと炭素生成挙動はSMR反応と無関係であった。一方,Pt担持量が0.1 wt%だと炭素析出は起こらなかった。これらの結果からPt/α-Al2O3触媒上には三つの活性サイトが形成されたと考えた。一つ目はDMSの影響を受けない活性点,二つ目はDMSにより活性を失うがDMSの供給を停止すると完全に再生する活性点,三つ目はSMRの活性点ではなくシンタリングしたPtがメタン分解を促進して炭素を生成する活性点である

    Epigenetic Memories in Hematopoietic Stem and Progenitor Cells

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    The recent development of next-generation sequencing (NGS) technologies has contributed to research into various biological processes. These novel NGS technologies have revealed the involvement of epigenetic memories in trained immunity, which are responses to transient stimulation and result in better responses to secondary challenges. Not only innate system cells, such as macrophages, monocytes, and natural killer cells, but also bone marrow hematopoietic stem cells (HSCs) have been found to gain memories upon transient stimulation, leading to the enhancement of responses to secondary challenges. Various stimuli, including microbial infection, can induce the epigenetic reprogramming of innate immune cells and HSCs, which can result in an augmented response to secondary stimulation. In this review, we introduce novel NGS technologies and their application to unraveling epigenetic memories that are key in trained immunity and summarize the recent findings in trained immunity. We also discuss our most recent finding regarding epigenetic memory in aged HSCs, which may be associated with the exposure of HSCs to aging-related stresses

    Reverse water-gas shift reaction over Pt/MoOx/TiO2 : reverse Mars-van Krevelen mechanism via redox of supported MoOx

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    The reverse water-gas shift (RWGS) reaction is a promising catalytic route for reducing CO2 emissions because its product, CO, is a key intermediate in various industrialized catalytic processes that produce fuels and chemicals. We describe herein a MoOx/TiO2-supported Pt catalyst (Pt(3)/MoOx(15)/TiO2; Pt loading = 3 wt%, MoO3 loading = 15 wt%) that promotes the RWGS reaction at low temperature (200-300 degrees C) with high activity and selectivity. The catalytic performance for both CO2 conversion and selectivity of Pt(3)/MoOx(15)/TiO2 is better than those of Pt catalysts on other supports and other metal catalysts supported on MoOx(15)/TiO2, as well as Cu- and Fe-Cr-based industrial catalysts. Moreover, results of operando X-ray absorption spectroscopy studies show that the reaction takes place via the reverse Mars-van Krevelen mechanism where H-2 acts as a reducing agent to create oxygen vacancies on the supported Mo oxide species that are filled by CO2 as an oxidizing agent

    Roles of the basic metals La, Ba, and Sr as additives in Al2O3-supported Pd-based three-way catalysts

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    Three-way catalytic converters are widely used to regulate emissions from gasoline-powered vehicles. Although significant effort over the past 40 years has resulted in the discovery of several metal additives that improve the thermal stability of three-way catalysts (TWCs), their effects on the actual catalytic process have not been studied systematically. The present work examines the roles of the typical basic metal additives La, Ba, and Sr in Pd-based TWC systems, using various spectroscopic and kinetic studies. Metallic Pd-0 species on Sr/Al2O3 and Ba/Al2O3 supports were found to be more electron-rich than those on pristine Al2O3, whereas those on La/Al2O3 were more electron-deficient. Consequently, Pd/La/Al2O3 showed a lessened CO poisoning effect during NO reduction reactions. Evaluations were performed using powdered catalysts as well as monolithic honeycomb catalysts under conditions simulating actual use. Pd/La/Al2O3 was observed to promote the catalytic reduction of NO most efficiently, while Pd/Ba/Al2O3 exhibited the highest activity for the oxidations of CO and C3H6. The present data suggest that the optimal metal additive for a Pd-based TWC will be determined by the specific application. The selection of such metals should take into account not only the stability but also the promotional effect during the exhaust purification process. (C) 2021 Elsevier Inc. All rights reserved

    Tensile fracture characteristics of carbon fibers collected from the outer and inner parts of a CFRP laminate by thermal decomposition

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    Thermal decomposition treatment (TDT) is a typical recycling method for CFRP. However, the recovered CFs (rCFs) tend to show a decrease in performance owing to the thermo-oxidation during this process. In particular, the thermo-oxidation rates of the outer and inner parts of CFRP are different during TDT; thus, the amount of damage is different between the rCFs collected from the outer (oCFs) and inner (iCFs) parts of CFRP. This study investigated the tensile fracture characteristics of the oCFs and iCFs of the CFRP laminates subjected to TDT, through the single-fiber tensile test and fracture surface observations. The tensile strength of the iCFs was higher and presented a narrower variation than that of the oCFs because the fracture of iCFs occurred from the largest pit formed on the skin whereas that of oCFs occurred from the largest defect in the core. Finally, the strength distribution of the rCFs collected randomly from the TDT treated CFRP was estimated using a mixture distribution model with the aid of the experimental data. The model fitted the strength distribution well. The results indicated that the strength of the rCFs varied more widely with an increase in the number of rCFs undergoing the core fracture
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