Dendritic cell deficiencies persist seven months after SARS-CoV-2 infection

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 infection induces an exacerbated inflammation driven by innate immunity components. Dendritic cells (DCs) play a key role in the defense against viral infections, for instance plasmacytoid DCs (pDCs), have the capacity to produce vast amounts of interferon-alpha (IFN-α). In COVID-19 there is a deficit in DC numbers and IFN-α production, which has been associated with disease severity. In this work, we described that in addition to the DC deficiency, several DC activation and homing markers were altered in acute COVID-19 patients, which were associated with multiple inflammatory markers. Remarkably, previously hospitalized and nonhospitalized patients remained with decreased numbers of CD1c+ myeloid DCs and pDCs seven months after SARS-CoV-2 infection. Moreover, the expression of DC markers such as CD86 and CD4 were only restored in previously nonhospitalized patients, while no restoration of integrin β7 and indoleamine 2,3-dyoxigenase (IDO) levels were observed. These findings contribute to a better understanding of the immunological sequelae of COVID-19

SARS-CoV-2 viral load in nasopharyngeal swabs is not an independent predictor of unfavorable outcome

The aim was to assess the ability of nasopharyngeal SARS-CoV-2 viral load at first patient’s hospital evaluation to predict unfavorable outcomes. We conducted a prospective cohort study including 321 adult patients with confirmed COVID-19 through RT-PCR in nasopharyngeal swabs. Quantitative Synthetic SARS-CoV-2 RNA cycle threshold values were used to calculate the viral load in log10 copies/mL. Disease severity at the end of follow up was categorized into mild, moderate, and severe. Primary endpoint was a composite of intensive care unit (ICU) admission and/or death (n = 85, 26.4%). Univariable and multivariable logistic regression analyses were performed. Nasopharyngeal SARS-CoV-2 viral load over the second quartile (≥ 7.35 log10 copies/mL, p = 0.003) and second tertile (≥ 8.27 log10 copies/mL, p = 0.01) were associated to unfavorable outcome in the unadjusted logistic regression analysis. However, in the final multivariable analysis, viral load was not independently associated with an unfavorable outcome. Five predictors were independently associated with increased odds of ICU admission and/or death: age ≥ 70 years, SpO2, neutrophils > 7.5 × 103/µL, lactate dehydrogenase ≥ 300 U/L, and C-reactive protein ≥ 100 mg/L. In summary, nasopharyngeal SARS-CoV-2 viral load on admission is generally high in patients with COVID-19, regardless of illness severity, but it cannot be used as an independent predictor of unfavorable clinical outcome

A Relationship between Carotenoid Accumulation and the Distribution of Species of the Fungus Neurospora in Spain

The ascomycete fungus Neurospora is present in many parts of the world, in particular in tropical and subtropical areas, where it is found growing on recently burned vegetation. We have sampled the Neurospora population across Spain. The sampling sites were located in the region of Galicia (northwestern corner of the Iberian peninsula), the province of Cáceres, the city of Seville, and the two major islands of the Canary Islands archipelago (Tenerife and Gran Canaria, west coast of Africa). The sites covered a latitude interval between 27.88° and 42.74°. We have identified wild-type strains of N. discreta, N. tetrasperma, N. crassa, and N. sitophila and the frequency of each species varied from site to site. It has been shown that after exposure to light Neurospora accumulates the orange carotenoid neurosporaxanthin, presumably for protection from UV radiation. We have found that each Neurospora species accumulates a different amount of carotenoids after exposure to light, but these differences did not correlate with the expression of the carotenogenic genes al-1 or al-2. The accumulation of carotenoids in Neurospora shows a correlation with latitude, as Neurospora strains isolated from lower latitudes accumulate more carotenoids than strains isolated from higher latitudes. Since regions of low latitude receive high UV irradiation we propose that the increased carotenoid accumulation may protect Neurospora from high UV exposure. In support of this hypothesis, we have found that N. crassa, the species that accumulates more carotenoids, is more resistant to UV radiation than N. discreta or N. tetrasperma. The photoprotection provided by carotenoids and the capability to accumulate different amounts of carotenoids may be responsible, at least in part, for the distribution of Neurospora species that we have observed across a range of latitudes

Genomic investigations of unexplained acute hepatitis in children

Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children

Characterization of sulfided W/USY catalysts and their activity in hydrodesulfurization of gas oil | Caracterización de catalizadores sulfurados W/USY y su actividad en la hidrodesulfuración de gasóleo

[EN] Two catalysts of tungsten sulfide supported on an ultra-stable Y zeolite were prepared by impregnation with aqueous solutions of ammonium metatungstate at acidic (2.7) and basic (11) pH values. The catalysts were characterized by HRTEM, SEM-EDX and FT-IR of adsorbed NO to determine if the location and dispersion of the WS2 particles is changed after the activation of the catalyst, and what consequences this has on the catalyst activity during the HDS of gasoil. W-2.7 catalyst showed a higher concentration and homogeneous distribution of the WS2 structures on the external surface of the zeolite support, and a decreased amount within the zeolite cavities with respect to W-11. The catalyst prepared at pH=2.7 exhibited higher activity in the HDS of gasoil. The characterization results indicate that because of the size of the sulfur molecules present in the gasoil, their hydrodesulfurization occurs mainly on the external surface of the zeolite, where this catalyst displays a superior dispersion of the WS2 species.[ES] Se prepararon dos catalizadores de WS2 soportados en zeolita Y ultra estable mediante impregnación con soluciones acuosas de metatungstato de amonio a pH ácido (2.7) y básico (11). Estos catalizadores se caracterizaron por HRTEM, SEM-EDX y adsorción de NO (FT-IR) para determinar si la localización y dispersión de las especies de sulfuro de W cambia después del proceso de activación y qué consecuencias tiene este cambio en la actividad catalítica para hidrodesulfuración (HDS) de gasóleo. El catalizador W-2.7 mostró una mayor concentración y distribución homogénea de las estructuras laminares de WS2 en la superficie externa de la zeolita, así como una menor dispersión de WS2 dentro de sus cavidades, con respecto a W-11. El catalizador W-2.7 mostró una mayor actividad en la hidrodesulfuración de gasóleo. Los resultados de caracterización indican que debido al tamaño de las moléculas de azufre presentes en el gasóleo, su hidrodesulfuración ocurre predominantemente en la superficie externa de la zeolita, donde este catalizador mostró mayor dispersión de las especies de WS2.Al apoyo financiero de DGICyT, Ministerio de Ciencia y Tecnología, Espana, proyecto BQU2001- ˜ 2126, y al Programa de Cooperacion Bilateral ´ CSIC(Espana) ˜ /CONACYT (Mexico). A Toural ´Quiroga por su ayuda en las mediciones de actividad catalítica.Peer Reviewe

A Mesoporous Zirconium-Isophthalate Multifunctional Platform

International audienceMIP-206, a mesoporous MOF built with feedstock isophthalate and both Zr 6 and Zr 12 oxo-clusters under green scalable conditions, features good pore accessibility, excellent thermal and chemical stability, and outstanding chemical diversity and tunability. MIP-206s loaded with palladium nanoparticles act as efficient and durable catalysts for the dehydrogenation of formic acid. This paves the way toward the utilization of MIP-206 as a robust mesoporous platform for a wide range of potential applications

A Mesoporous Zirconium-Isophthalate Multifunctional Platform

Mesoporous materials suffer from limitations including poor crystallinity and hydrolytic stability, lack of chemical diversity, insufficient pore accessibility, complex synthesis and toxicity issues. Here the association of non-toxic Zr-oxo clusters and feedstock isophthalic acid (IPA) via a Homometallic-Multicluster-Dot strategy results in a robust crystalline mesoporous MOF, denoted as MIP-206, that overcomes the aforementioned limitations. MIP-206, built up from an unprecedented combination of Zr6 and Zr12 oxo-cluster inorganic building units into a single structure, exhibits accessible meso-channels of ca. 2.6 nm and displays excellent chemical stability under different hydrolytic and harsh conditions. Owing to the abundant variety of functionalized IPA linkers, the chemical environment of MIP-206 can be easily tuned without hampering pore accessibility due to its large pore windows. As a result, MIP-206 loaded with palladium nanoparticles acts as an efficient and durable catalyst for the dehydrogenation of formic acid under mild conditions, outperforming benchmark mesoporous materials. This paves the way towards the utilization of MIP-206 as a robust mesoporous platform for a wide range of potential applications.</p