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Alexander Egbe Sorin V. Pislaru Mahmoud A. Ali Arooj R. Khan Amber N. Boler Hartzell V. Schaff Emmanuel Akintoye Heidi M. Connolly Vuyisile T. Nkomo Patricia A. Pellikka 《JACC: Cardiovascular Imaging》2018,11(7):951-958
Objectives
The purpose of this study was to review the institutional practice of surveillance transthoracic echocardiography (TTE) for diagnosing early prosthetic valve dysfunction (PVD).Background
Bioprosthetic valve thrombosis (BPVT) is an important cause of PVD, and guidelines do not recommend routine TTE during the first 5 years after valve implantation.Methods
The authors performed a retrospective case-control study of all suspected (imaging diagnosis) or confirmed (histopathological diagnosis) cases of BPVT from January 1997 through December 2016. Patients were matched 1:2 (age, sex, prosthesis position) to patients whose prostheses were explanted because of structural failure (SF). PVD was defined as a 50% increase above baseline gradient at valve implantation and classified as early (≤5 years) or late (>5 years) after implantation.Results
There were 94 BPVT (51 suspected, 43 confirmed) and 188 SF cases; patient age 61 ± 9 years; men 61 (65%). The prosthesis positions were aortic 56%; mitral 26%; tricuspid 15%; and pulmonary 3%. Early PVD was more common in the BPVT versus SF group: 83 of 94 (88%) versus 20 of 188 (11%) (p < 0.001). Time from implantation to PVD was shorter for BPVT than SF: 26 months (interquartile range [IQR]: 12 to 43 months) versus 74 months (IQR: 48 to 102 months) (p < 0.001). At the initial PVD diagnosis, 81% of BPVT and 90% of SF patients were asymptomatic. However, BPVT patients had rapid symptomatic deterioration, requiring intervention sooner after PVD diagnosis: 6 months (IQR: 4 to 7 months) versus 51 months (IQR: 22 to 55 months) (p < 0.001).Conclusions
Most patients with PVD due to BPVT were asymptomatic at initial diagnosis, which was made based on routine surveillance TTE, often performed before 5 years. BPVT, an acute disease process, requires timely diagnosis because patient conditions rapidly deteriorate. Further studies are needed to determine whether routine surveillance TTE should be considered for patients with bioprosthetic valves to identify pre-symptomatic features of BPVT in order to provide effective, appropriate therapy. 相似文献44.
Peikert T Finkielman JD Hummel AM McKenney ME Gregorini G Trimarchi M Specks U 《Arthritis and rheumatism》2008,58(5):1546-1551
OBJECTIVE: Antineutrophil cytoplasmic antibodies (ANCA) binding to neutrophil elastase (NE) and proteinase 3 (PR3) are detectable in most patients with cocaine-induced midline destructive lesions (CIMDL), but the pathogenic role and antigen specificity of these antibodies are unknown. This study was undertaken to assess the effects of NE ANCA on the enzymatic activity of NE, to determine whether these antibodies interfere with the physiologic effect of secretory leukoprotease inhibitor (SLPI), and to investigate the antigen specificity of both NE and PR3 ANCA in patients with CIMDL. We also compared the binding of PR3 ANCA in patients with CIMDL with that in patients with Wegener's granulomatosis (WG). METHODS: PR3 ANCA and NE ANCA were detected by capture enzyme-linked immunosorbent assays (ELISAs) and by indirect immunofluorescence. IgG was purified from the patients' sera, and the influence of NE ANCA on the enzymatic activity of NE and on the inhibitory activity of SLPI was investigated by determining the hydrolysis of N-methoxysuccinyl-Ala-Ala-Pro-Val p-nitroanilide by NE. RESULTS: IgG from NE ANCA-positive sera of patients with CIMDL inhibited the enzymatic activity of NE and did not interfere with the activity of SLPI. In contrast to the findings in WG sera, measurement of PR3 ANCA in CIMDL sera showed only fair to moderate concordance between the 2 different capture ELISAs. Cross-inhibition experiments demonstrated that NE ANCA and PR3 ANCA represent distinct autoantibodies in patients with CIMDL. CONCLUSION: The functional effects of NE ANCA on the enzymatic activity of NE or on the activity of SLPI cannot be implicated in the pathogenesis of CIMDL. The autoimmune reaction that targets neutrophil serine proteases in patients with CIMDL is frequently directed against more than one antigen. The ANCA response, including the reactivity of PR3 ANCA, in patients with CIMDL differs from what has been described in patients with WG. 相似文献
45.
Hanchen Xu Kevin Van der Jeught Zhuolong Zhou Lu Zhang Tao Yu Yifan Sun Yujing Li Changlin Wan Ka Man So Degang Liu Michael Frieden Yuanzhang Fang Amber L. Mosley Xiaoming He Xinna Zhang George E. Sandusky Yunlong Liu Samy O. Meroueh Chi Zhang Aruna B. Wijeratne Cheng Huang Guang Ji Xiongbin Lu 《The Journal of clinical investigation》2021,131(10)
One of the primary mechanisms of tumor cell immune evasion is the loss of antigenicity, which arises due to lack of immunogenic tumor antigens as well as dysregulation of the antigen processing machinery. In a screen for small-molecule compounds from herbal medicine that potentiate T cell–mediated cytotoxicity, we identified atractylenolide I (ATT-I), which substantially promotes tumor antigen presentation of both human and mouse colorectal cancer (CRC) cells and thereby enhances the cytotoxic response of CD8+ T cells. Cellular thermal shift assay (CETSA) with multiplexed quantitative mass spectrometry identified the proteasome 26S subunit non–ATPase 4 (PSMD4), an essential component of the immunoproteasome complex, as a primary target protein of ATT-I. Binding of ATT-I with PSMD4 augments the antigen-processing activity of immunoproteasome, leading to enhanced MHC-I–mediated antigen presentation on cancer cells. In syngeneic mouse CRC models and human patient–derived CRC organoid models, ATT-I treatment promotes the cytotoxicity of CD8+ T cells and thus profoundly enhances the efficacy of immune checkpoint blockade therapy. Collectively, we show here that targeting the function of immunoproteasome with ATT-I promotes tumor antigen presentation and empowers T cell cytotoxicity, thus elevating the tumor response to immunotherapy. 相似文献
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Jonathan Bryant-Genevier Carol Y. Rao Barbara Lopes-Cardozo Ahoua Kone Charles Rose Isabel Thomas Diana Orquiola Ruth Lynfield Dhara Shah Lori Freeman Scott Becker Amber Williams Deborah W. Gould Hope Tiesman Geremy Lloyd Laura Hill Ramona Byrkit 《MMWR. Morbidity and mortality weekly report》2021,70(26):947
48.
Chiaravalloti Nancy D. Amato Maria Pia Brichetto Giampaolo Chataway Jeremy Dalgas Ulrik DeLuca John Meza Cecilia Moore Nancy B. Feys Peter Filippi Massimo Freeman Jennifer Inglese Matilde Motl Rob Rocca Maria Assunta Sandroff Brian M. Salter Amber Cutter Gary Feinstein Anthony 《Journal of neurology》2021,268(5):1598-1607
Journal of Neurology - Individuals with pre-existing chronic illness have shown increased anxiety and depression due to COVID-19. Here, we examine the impact of the COVID-19 pandemic on emotional... 相似文献
49.
Pranshuta Sabharwal Sangeeta Chakraborty Niraj Tyagi Amber Kumar 《Indian Journal of Critical Care Medicine》2021,25(2):238
How to cite this article: Sabharwal P, Chakraborty S, Tyagi N, Kumar A. Acute Flaccid Quadriparesis in a Recovering COVID-19 Patient: A Clinical Dilemma. Indian J Crit Care Med 2021;25(2):238–239. 相似文献
50.
Stephanie M. Thornber Lucy M. Mottram Amber R. Mason Paul Thompson Martin C. Stennett Neil C. Hyatt 《RSC advances》2020,10(54):32497
The immobilisation and disposal of fissile materials from civil and defence nuclear programmes requires compatible, passively safe and proliferation resistant wasteforms. In this study, we demonstrate the application of an albite glass–zirconolite ceramic material for immobilisation of chloride contaminated plutonium oxide residues in the United Kingdom. The chlorine solubility limit in the albite glass phase was determined to be 1.0 ± 0.1 wt%, above the maximum envisaged chorine inventory of 0.5 wt%, attainable at a 20 wt% PuO2 incorporation rate within the ceramic. Cl K-edge of X-ray Absorption Near Edge Spectroscopy (XANES) was exploited to confirm partitioning of Cl to the glass phase, speciated as the chloride anion, with exsolution of crystalline NaCl above the chlorine solubility limit. Combinatorial fitting of Cl XANES data, utilising a library of chemically plausible reference spectra, demonstrated the association of Cl with Na and Ca modifier cations, with environments characteristic of the aluminosilicate chloride minerals eudialyte, sodalite, chlorellestadite and afghanite. Adventitious incorporation of Ca, Zr and Ti within the albite glass phase apparently assists chlorine solubility, by templating a local chemical environment characteristic of the mineral reference compounds. The partitioning of Ce, as a Pu analogue, within the glass–ceramic was not adversely impacted by incorporation of Cl. The significance of this research is in demonstrating the compatibility of the glass–ceramic wasteform toward Cl solubility at the expected incorporation rate, below the determined solubility limit. Thus, an upstream heat treatment facility to remove chloride contamination, as specified in the current conceptual flowsheet, would not be required from the perspective of wasteform compatibility, thus providing scope to de-risk the technology roadmap and reduce the projected capital and operational plant costs.Understanding chlorine speciation and incorporation in glass ceramic wasteforms underpins future treatment of contaminated plutonium residues. 相似文献