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Federica Bozzano Chiara Dentone Carola Perrone Antonio Di Biagio Daniela Fenoglio Alessia Parodi Malgorzata Mikulska Bianca Bruzzone Daniele Roberto Giacobbe Antonio Vena Lucia Taramasso Laura Nicolini Nicol Patroniti Paolo Pelosi Angelo Gratarola Raffaele De Palma Gilberto Filaci Matteo Bassetti Andrea De Maria 《PLoS pathogens》2021,17(4)
The SARS-CoV-2 infection causes severe respiratory involvement (COVID-19) in 5–20% of patients through initial immune derangement, followed by intense cytokine production and vascular leakage. Evidence of immune involvement point to the participation of T, B, and NK cells in the lack of control of virus replication leading to COVID-19. NK cells contribute to early phases of virus control and to the regulation of adaptive responses. The precise mechanism of NK cell dysregulation is poorly understood, with little information on tissue margination or turnover. We investigated these aspects by multiparameter flow cytometry in a cohort of 28 patients hospitalized with early COVID-19.Relevant decreases in CD56brightCD16+/- NK subsets were detected, with a shift of circulating NK cells toward more mature CD56dimCD16+KIR+NKG2A+ and “memory” KIR+CD57+CD85j+ cells with increased inhibitory NKG2A and KIR molecules. Impaired cytotoxicity and IFN-γ production were associated with conserved expression of natural cytotoxicity receptors and perforin. Moreover, intense NK cell activation with increased HLA-DR and CD69 expression was associated with the circulation of CD69+CD103+ CXCR6+ tissue-resident NK cells and of CD34+DNAM-1brightCXCR4+ inflammatory precursors to mature functional NK cells. Severe disease trajectories were directly associated with the proportion of CD34+DNAM-1brightCXCR4+ precursors and inversely associated with the proportion of NKG2D+ and of CD103+ NK cells.Intense NK cell activation and trafficking to and from tissues occurs early in COVID-19, and is associated with subsequent disease progression, providing an insight into the mechanism of clinical deterioration. Strategies to positively manipulate tissue-resident NK cell responses may provide advantages to future therapeutic and vaccine approaches. 相似文献
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Noji Thomas T.; Bathmann Ulrich V.; Bodungen Bodo von; Voss Maren; Antia Avan; Krumbholz Manta; Klein Bert; Peeken Ilka; Noji Carola I.-M.; Rey Francisco 《Journal of plankton research》1997,19(7):863-875
Findings from experiments showed that the web-feeding euthecosomatouspteropod, Limacina retroversa, can produce rapidly sinking,mucous aggregates. It is suggested that, by adhesion, theseaggregates scavenged picoplankton-sized particles, which werethus effectively cleared from the medium. In contrast, Calanusfinmarchicus was not able to clear these particles in our experiments.Sedimentation velocities of 10 aggregates measured in vivo wereup to 1000 m day1, with an average of {small tilde}300m day1 (not including two aggegates with neutral buoyancy).Mean velocities measured for feces of C.finmarchicus, Calanushyperboreus and Thyssnoessa sp. were consider ably lower. Wesuggest that the sedimentation of L retroversa aggregates wasthe source of mucous flocs collected in sediment traps (Bathmannet al., Deep-Sea Res., 38,13411360,1991) and at the seafloor at 1200 m depth in the southern Norwegian Sea. This processmay be an important mediator of sedimentation to the deep sea,when these pteropods are present in surface waters in largeabundance. 相似文献
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Christian Kuberski Hartmut Scheibner Carola Steup Beate Diettrich Martin Luckner 《Phytochemistry》1984,23(7):1407-1412
Digitalis lanata strain VII from filament callus grew in small cell colonies in nutrient media with high auxin activity. Upon increasing the cytoki 相似文献
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When the acetogen Clostridium formicoaceticum was cultivated on mixtures of aromatic compounds (e.g., 4-hydroxybenzaldehyde plus vanillate), the oxidation of aromatic
aldehyde groups occurred more rapidly than did O-demethylation. Likewise, when fructose and 4-hydroxybenzaldehyde were simultaneously
provided as growth substrates, fructose was utilized only after the aromatic aldehyde group was oxidized to the carboxyl level.
Aromatic aldehyde oxidoreductase activity was constitutive (activities approximated 0.8 U mg–1), and when pulses of 4-hydroxybenzaldehyde were added during fructose-dependent growth, the rate at which fructose was utilized
decreased until 4-hydroxybenzaldehyde was consumed. Although 4-hydroxybenzaldehyde inhibited the capacity of cells to metabolize
fructose, lactate or gluconate were consumed simultaneously with 4-hydroxybenzaldehyde, and lactate or aromatic compounds
lacking an aldehyde group were utilized concomitantly with fructose. These results demonstrate that (1) aromatic aldehydes
can be utilized as cosubstrates and have negative effects on the homoacetogenic utilization of fructose by C. formicoaceticum, and (2) the consumption of certain substrates by this acetogen is not subject to catabolite repression by fructose.
Received: 14 May 1998 / Accepted: 7 August 1998 相似文献
128.
Henry W. Newman Carola Purdy Lowell Rantz F.C. Hill Jr. 《The Western journal of medicine》1958,89(6):387-389
Cultures on anaerobic medium were made of the spinal fluids of 27 patients with multiple sclerosis and 13 controls after the method described recently by Ichelson. Where Ichelson found organisms resembling spirochetes in 78 per cent of patients with multiple sclerosis, we found some form of what appeared to be a living micro-organism in 18.5 per cent. The control fluids were all sterile. The work requires confirmation and amplification. 相似文献
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