Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted on mink farms between minks and humans in many countries. However, the systemic pathological features of ...SARS-CoV-2-infected minks are mostly unknown. Here, we demonstrated that minks were largely permissive to SARS-CoV-2, characterized by severe and diffuse alveolar damage, and lasted at least 14 days post inoculation (dpi). We first reported that infected minks displayed multiple organ-system lesions accompanied by an increased inflammatory response and widespread viral distribution in the cardiovascular, hepatobiliary, urinary, endocrine, digestive, and immune systems. The viral protein partially co-localized with activated Mac-2
macrophages throughout the body. Moreover, we first found that the alterations in lipids and metabolites were correlated with the histological lesions in infected minks, especially at 6 dpi, and were similar to that of patients with severe and fatal COVID-19. Particularly, altered metabolic pathways, abnormal digestion, and absorption of vitamins, lipids, cholesterol, steroids, amino acids, and proteins, consistent with hepatic dysfunction, highlight metabolic and immune dysregulation. Enriched kynurenine in infected minks contributed to significant activation of the kynurenine pathway and was related to macrophage activation. Melatonin, which has significant anti-inflammatory and immunomodulating effects, was significantly downregulated at 6 dpi and displayed potential as a targeted medicine. Our data first illustrate systematic analyses of infected minks to recapitulate those observations in severe and fetal COVID-19 patients, delineating a useful animal model to mimic SARS-CoV-2-induced systematic and severe pathophysiological features and provide a reliable tool for the development of effective and targeted treatment strategies, vaccine research, and potential biomarkers.
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•SDSO intercalated CuMgAl-LDH was successfully prepared.•CuMgAl-SDSO-LDO was novelly employed as NH3-SCR catalyst.•The best carbon doped Cu-based oxides candidate was determined.•The ...reasons for different DeNOx performance of Cu-based oxides were revealed.
In this work, sodium dodecyl sulfonate (SDSO) intercalated CuMgAl Layered double hydroxide (CuMgAl-SDSO-LDH) was fabricated and derived catalyst (CuMgAl-SDSO-LDO) was innovatively evaluated as potential candidates for low temperature selective catalytic reduction of NO with NH3 (NH3-SCR). The results indicated that the existence of carbon from SDSO obviously affected the denitrification activity of CuMgAl-NO3-LDO, besides, the successful intercalation of SDSO was essential to catalytic performance. Series of characterizations analysis revealed that the best performance for CuMgAl-SDSO-LDO catalyst could be ascribed to higher dispersion and more appropriate valence state distribution of Cu, which were intrinsically relative with the moderate carbon doping content, thus leading to excellent SCR performance with 90% NOx conversion at 210 °C, above 75 % N2 selectivity at 90–330 °C and strong H2O/SO2 resistance ability. This work may provide a novel method to develop the carbon doped Cu-based catalysts and expand the applications of LDH in the field of SCR.
Background
Cardiovascular diseases (CVDs) and diabetes mellitus (DM) are top two chronic comorbidities that increase the severity and mortality of COVID‐19. However, how SARS‐CoV‐2 alters the ...progression of chronic diseases remain unclear.
Methods
We used adenovirus to deliver h‐ACE2 to lung to enable SARS‐CoV‐2 infection in mice. SARS‐CoV‐2’s impacts on pathogenesis of chronic diseases were studied through histopathological, virologic and molecular biology analysis.
Results
Pre‐existing CVDs resulted in viral invasion, ROS elevation and activation of apoptosis pathways contribute myocardial injury during SARS‐CoV‐2 infection. Viral infection increased fasting blood glucose and reduced insulin response in DM model. Bone mineral density decreased shortly after infection, which associated with impaired PI3K/AKT/mTOR signaling.
Conclusion
We established mouse models mimicked the complex pathological symptoms of COVID‐19 patients with chronic diseases. Pre‐existing diseases could impair the inflammatory responses to SARS‐CoV‐2 infection, which further aggravated the pre‐existing diseases. This work provided valuable information to better understand the interplay between the primary diseases and SARS‐CoV‐2 infection.
Evidence suggests associations between COVID-19 patients or vaccines and glycometabolic dysfunction and an even higher risk of the occurrence of diabetes. Herein, we retrospectively analyzed ...pancreatic lesions in autopsy tissues from 67 SARS-CoV-2 infected non-human primates (NHPs) models and 121 vaccinated and infected NHPs from 2020 to 2023 and COVID-19 patients. Multi-label immunofluorescence revealed direct infection of both exocrine and endocrine pancreatic cells by the virus in NHPs and humans. Minor and limited phenotypic and histopathological changes were observed in adult models. Systemic proteomics and metabolomics results indicated metabolic disorders, mainly enriched in insulin resistance pathways, in infected adult NHPs, along with elevated fasting C-peptide and C-peptide/glucose ratio levels. Furthermore, in elder COVID-19 NHPs, SARS-CoV-2 infection causes loss of beta (β) cells and lower expressed-insulin in situ characterized by islet amyloidosis and necrosis, activation of α-SMA and aggravated fibrosis consisting of lower collagen in serum, an increase of pancreatic inflammation and stress markers, ICAM-1 and G3BP1, along with more severe glycometabolic dysfunction. In contrast, vaccination maintained glucose homeostasis by activating insulin receptor α and insulin receptor β. Overall, the cumulative risk of diabetes post-COVID-19 is closely tied to age, suggesting more attention should be paid to blood sugar management in elderly COVID-19 patients.
The Omicron variants of SARS-CoV-2, primarily authenticated in November 2021 in South Africa, has initiated the 5th wave of global pandemics. Here, we systemically examined immunological and ...metabolic characteristics of Omicron variants infection. We found Omicron resisted to neutralizing antibody targeting receptor binding domain (RBD) of wildtype SARS-CoV-2. Omicron could hardly be neutralized by sera of Corona Virus Disease 2019 (COVID-19) convalescents infected with the Delta variant. Through mass spectrometry on MHC-bound peptidomes, we found that the spike protein of the Omicron variants could generate additional CD8 + T cell epitopes, compared with Delta. These epitopes could induce robust CD8 + T cell responses. Moreover, we found booster vaccination increased the cross-memory CD8 + T cell responses against Omicron. Metabolic regulome analysis of Omicron-specific T cell showed a metabolic profile that promoted the response of memory T cells. Consistently, a greater fraction of memory CD8 + T cells existed in Omicron stimulated peripheral blood mononuclear cells (PBMCs). In addition, CD147 was also a receptor for the Omicron variants, and CD147 antibody inhibited infection of Omicron. CD147-mediated Omicron infection in a human CD147 transgenic mouse model induced exudative alveolar pneumonia. Taken together, our data suggested that vaccination booster and receptor blocking antibody are two effective strategies against Omicron.
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•A catalyst with tunable CuOx species distribution was prepared.•The optimal CuAl-LDO/carbon nanotubes catalyst for NH3-SCR was determined.•A synergistic mechanism of Cu2O/CuO ...denitration was proposed.•An effective way to improve the denitration performance of CuOx species was confirmed.
Cu-based catalysts have drawn much attention in ammonia-selective catalytic reduction (NH3-SCR) of NOx because of their outstanding low-temperature denitration (de-NOx) potential. Although satisfactory SCR performance was obtained with support from the catalytic activity of CuOx species in recent studies, the effect of the valence distribution of CuOx species on NH3-SCR reaction is still ambiguous, and elaborate exploration is necessary. Here, a series of CuAl-layered double oxide/carbon nanotubes-x (CuAl-LDO/CNTs-x) nanocatalysts with a tunable valence distribution of highly dispersed CuOx species was constructed from the topotactic transformation of CuAl-layered double hydroxide (CuAl-LDH) precursor and a controllable carbothermal reduction reaction. Multiple characterization techniques, including XRD, NH3-TPD, H2-TPR, NOx-TPD, XPS, in situ DRIFTS, and HR-TEM, were employed to elucidate the inherent relationship between the chemical properties and catalytic activity of the as-prepared catalysts. The obtained CuAl-LDO/CNTs-2 catalyst exhibited optimum catalytic performance, with NOx conversion exceeding 90% in the temperature range 180–305 °C. Such high catalytic efficiency can be attributed to the appropriate valence distribution of CuOx species, which can significantly improve the redox capacity and surface acidity of the catalysts, thereby promoting the adsorption and activation of the reactants. Combined with further theoretical calculation, a synergistic catalytic mechanism of Cu2O/CuO in the NH3-SCR reaction is tentatively proposed. Notably, the CuO active center can function as the dominant adsorption site of NO and NH3 to promote the formation of NO+ active species and the dehydrogenation activation of NH3. The Cu2O active center can act as the adsorption site for O, promoting the formation of active oxygen species O−. Consequently, the synergistic effect between Cu2O and CuO can lead to the rapid formation of reactive intermediates, proceeding via the Langmuir–Hinshelwood (reaction between adsorbed NH3 and adsorbed NOx) or Eley–Rideal (reaction between adsorbed NH3 and gaseous NO) mechanism reaction routes to complete the catalytic cycle. This work provides a fundamental understanding on Cu2O/CuO synergistic catalysis of NH3-SCR, which is propitious for the rational design and optimization of Cu-based oxide de-NOx catalysts.
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