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31.
Catherine Riou Elsa du Bruyn Cari Stek Remy Daroowala Rene T. Goliath Fatima Abrahams Qonita Said-Hartley Brian W. Allwood Nei-Yuan Hsiao Katalin A. Wilkinson Cecilia S. Lindestam Arlehamn Alessandro Sette Sean Wasserman Robert J. Wilkinson 《The Journal of clinical investigation》2021,131(12)
T cells are involved in control of coronavirus disease 2019 (COVID-19), but limited knowledge is available on the relationship between antigen-specific T cell response and disease severity. Here, we used flow cytometry to assess the magnitude, function, and phenotype of SARS coronavirus 2–specific (SARS-CoV-2–specific) CD4+ T cells in 95 hospitalized COVID-19 patients, 38 of them being HIV-1 and/or tuberculosis (TB) coinfected, and 38 non–COVID-19 patients. We showed that SARS-CoV-2–specific CD4+ T cell attributes, rather than magnitude, were associated with disease severity, with severe disease being characterized by poor polyfunctional potential, reduced proliferation capacity, and enhanced HLA-DR expression. Moreover, HIV-1 and TB coinfection skewed the SARS-CoV-2 T cell response. HIV-1–mediated CD4+ T cell depletion associated with suboptimal T cell and humoral immune responses to SARS-CoV-2, and a decrease in the polyfunctional capacity of SARS-CoV-2–specific CD4+ T cells was observed in COVID-19 patients with active TB. Our results also revealed that COVID-19 patients displayed reduced frequency of Mycobacterium tuberculosis–specific CD4+ T cells, with possible implications for TB disease progression. These results corroborate the important role of SARS-CoV-2–specific T cells in COVID-19 pathogenesis and support the concept of altered T cell functions in patients with severe disease. 相似文献
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Malignant mesothelioma (MM) is a connective tissue tumor with partial epithelioid differentiation. The pattern of proteoglycan (PG) expression by epithelioid and fibroblast-like (sarcomatoid) MM cells differ; cell surface PGs being more abundant in the former phenotype and matrix PGs in the latter. The differentiation as well as much of the malignant nature of these tumors is dependent on the expression of surface PGs. The syndecans, however, also translocate to the nucleus for an as yet unknown function. 相似文献
34.
Swathi Gujral Meryl A. Butters Alexandre Y. Dombrovski Katalin Szanto 《The American journal of geriatric psychiatry》2021,29(7):709-713
ObjectivesThis study examined whether late-onset (versus early-onset) suicidal behavior is associated with worse cognition.MethodsParticipants included 278 adults aged 50+ years (56 nonpsychiatric comparison group; 67 nonsuicidal depressed older adults; 63 depressed suicide ideators; and 44 late-onset (55+ years) and 48 early-onset suicide attempters (<55 years). Using a case-control design, this study examined group differences in global cognition, episodic memory, information processing speed, and executive functioning, assessed using the Repeatable Battery of Neuropsychological Status and the Trail Making Test from the Delis-Kaplan Executive Function System. Linear regression was used for data analyses.ResultsBoth attempter groups displayed worse executive functioning than nonsuicidal depressed older adults. Late-onset attempters additionally displayed poorer global cognition and processing speed than nonsuicidal depressed older adults and poorer memory than early-onset attempters.ConclusionsLate-onset suicidal behavior is associated with worse performance in a broad range of cognitive domains, possibly reflective of a dementia prodrome. 相似文献
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Heltai K Kis Z Burian K Endresz V Veres A Ludwig E Gönczöl E Valyi-Nagy I 《Atherosclerosis》2004,173(2):339-346
The relative significance of traditional risk factors, chronic infections and autoimmune processes in the development of acute myocardial infarction (AMI) has not been fully elucidated. We compared serum IgG antibody titres to various pathogens, i.e. Chlamydia pneumoniae (Cpn), cytomegalovirus (CMV) and herpes simplex virus type 1 (HSV-1), and to the potential autoantigens human heat shock protein 60 (hHSP60) and mycobacterial heat shock protein 65 (mHSP65), in serum samples obtained from patients 3-48 h after AMI (n = 40) or stable effort angina (SEA, n = 43), and from controls (n = 46). The strongest association was observed between AMI and the elevated level of hHSP60 antibodies. The association between AMI and the level of Cpn antibodies was also significant. High levels of hHSP60 and Cpn antibodies represented independent risk factors for the development of AMI, but the simultaneous presence of high levels of antibodies to Cpn and hHSP60 suggested a joint effect on the relative risk of AMI (OR = 12.0-21.1). The antibody titres to mHSP65 were higher in the SEA group than in the controls, and the simultaneous presence of high levels of Cpn and mHSP65 antibodies meant an increased risk among the SEA patients. The antibody titres to CMV or HSV-1 were similar in the three groups. In conclusion, these results demonstrate associations of AMI with high levels of anti-hHSP60 and anti-Cpn antibodies, and of SEA with the level of anti-mHSP65 antibodies, these being independent risk factors. 相似文献
37.
A recurrent synonymous KAT6B mutation causes Say‐Barber‐Biesecker/Young‐Simpson syndrome by inducing aberrant splicing 下载免费PDF全文
38.
Katalin Czifrák József Karger‐Kocsis Lajos Daróczi Miklós Zsuga Sándor Kéki 《Macromolecular chemistry and physics.》2014,215(19):1896-1907
A series of novel segmented linear and crosslinked polyurethanes (PUs) are synthesized from poly(ε‐caprolactone) (PCL) (25 kg mol?1), methylene diphenyl diisocyanate (MDI), and various polyether diols (Pluronic (PLU) and polyethylene glycol (PEG)). The basic structures of the highly deformable PUs are PLU/PEG–MDI–PCL–MDI–PLU/PEG and PLU–MDI–PCL–MDI–PLU, respectively. The linear and crosslinked PUs are characterized. Changes in the tensile behavior are attributed to the effects of compositional variables and alterations in the crosslink density. Additional information on the morphology of the segmented PUs is deduced from differential scanning calorimetry, as well as transmission and scanning electron microscopy investigations. Both the linear and the crosslinked PUs exhibit a broad rubbery plateau above the melting temperature of the crystalline PCL phase, which is highly beneficial for shape memory function. This work highlights that the chemical build‐up of soft segments containing high‐molecular‐weight crystallizable chain units is a proper tool to tailor the morphology and mechanical properties of PUs, and thus also their shape memory properties.
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Fadila Hadj-Bouziane Ning Liu Andrew H. Bell Katalin M. Gothard Wen-Ming Luh Roger B. H. Tootell Elisabeth A. Murray Leslie G. Ungerleider 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(52):E3640-E3648