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1.
J Med Virol ; 94(11): 5260-5270, 2022 11.
Article in English | MEDLINE | ID: mdl-35811284

ABSTRACT

Early kinetics of SARS-CoV-2 viral load (VL) in plasma determined by quantitative reverse-transcription polymerase chain reaction (RT-PCR) was evaluated as a predictor of poor clinical outcome in a prospective study and assessed in a retrospective validation cohort. Prospective observational single-center study including consecutive adult patients hospitalized with COVID-19 between November 2020 and January 2021. Serial plasma samples were obtained until discharge. Quantitative RT-PCR was performed to assess SARS-CoV-2 VL. The main outcomes were in-hospital mortality, admission to the Intensive Care Unit (ICU), and their combination (Poor Outcome). Relevant viremia (RV), established in the prospective study, was assessed in a retrospective cohort including hospitalized COVID-19 patients from April 2021 to May 2022, in which plasma samples were collected according to clinical criteria. Prospective cohort: 57 patients were included. RV was defined as at least a twofold increase in VL within ≤2 days or a VL > 300 copies/ml, in the first week. Patients with RV (N = 14; 24.6%) were more likely to die than those without RV (35.7% vs. 0%), needed ICU admission (57% vs. 0%) or had Poor Outcome (71.4% vs. 0%), (p < 0.001 for the three variables). Retrospective cohort: 326 patients were included, 18.7% presented RV. Patients with RV compared with patients without RV had higher rates of ICU-admission (odds ratio [OR]: 5.6 [95% confidence interval [CI]: 2.1-15.1); p = 0.001), mortality (OR: 13.5 [95% CI: 6.3-28.7]; p < 0.0001) and Poor Outcome (OR: 11.2 [95% CI: 5.8-22]; p < 0.0001). Relevant SARS-CoV-2 viremia in the first week of hospitalization was associated with higher in-hospital mortality, ICU admission, and Poor Outcome. Findings observed in the prospective cohort were confirmed in a larger validation cohort.


Subject(s)
COVID-19 , Adult , COVID-19/diagnosis , Hospitalization , Humans , Prospective Studies , Retrospective Studies , SARS-CoV-2 , Viremia
2.
Front Med (Lausanne) ; 9: 855639, 2022.
Article in English | MEDLINE | ID: mdl-35783606

ABSTRACT

Background: Interleukin 6 (IL6) levels and SARS-CoV-2 viremia have been correlated with COVID-19 severity. The association over time between them has not been assessed in a prospective cohort. Our aim was to evaluate the relationship between SARS-CoV-2 viremia and time evolution of IL6 levels in a COVID-19 prospective cohort. Methods: Secondary analysis from a prospective cohort including COVID-19 hospitalized patients from Hospital Universitario La Princesa between November 2020 and January 2021. Serial plasma samples were collected from admission until discharge. Viral load was quantified by Real-Time Polymerase Chain Reaction and IL6 levels with an enzyme immunoassay. To represent the evolution over time of both variables we used the graphic command twoway of Stata. Results: A total of 57 patients were recruited, with median age of 63 years (IQR [53-81]), 61.4% male and 68.4% Caucasian. The peak of viremia appeared shortly after symptom onset in patients with persistent viremia (more than 1 sample with > 1.3 log10 copies/ml) and also in those with at least one IL6 > 30 pg/ml, followed by a progressive increase in IL6 around 10 days later. Persistent viremia in the first week of hospitalization was associated with higher levels of IL6. Both IL6 and SARS-CoV-2 viral load were higher in males, with a quicker increase with age. Conclusion: In those patients with worse outcomes, an early peak of SARS-CoV-2 viral load precedes an increase in IL6 levels. Monitoring SARS-CoV-2 viral load during the first week after symptom onset may be helpful to predict disease severity in COVID-19 patients.

3.
Nanomaterials (Basel) ; 11(1)2021 Jan 13.
Article in English | MEDLINE | ID: mdl-33451099

ABSTRACT

Novel hybrid materials with integrated catalytic properties and hydrophobic response, C@Fe-Al2O3 hybrid samples, were presented and tested as catalysts for phenol reaction in aqueous solutions at atmospheric pressure and mild temperature conditions, using CO2 as a feedstock. A series of carbon-coated γ-alumina pellets (C@Fe-Al2O3) were synthesized and characterized by TGA, Brunauer-Emmett-Teller (BET) method, Raman spectroscopy, SEM, TEM, and XPS in order to get comprehensive knowledge of their properties at the nanoscale and relate them with their catalytic behavior. The results obtained correlated their catalytic activities with their carbon surface compositions. The application of these materials as active catalysts in the Kolbe-Schmitt reaction for CO2 conversion in aqueous media was proposed as an alternative reaction for the valorization of exhausts industrial effluents. In these early tests, the highest conversion of phenol was observed for the hybrid samples with the highest graphitic characteristic and the most hydrophobic behavior. Carboxylation products such as benzoic acid, p-hydroxybenzoic acid, and salicylic acid, have been identified under these experimental conditions.

4.
Beilstein J Nanotechnol ; 7: 197-208, 2016.
Article in English | MEDLINE | ID: mdl-26977377

ABSTRACT

This work addresses the formation and the internal morphology of polyelectrolyte layers obtained by the layer-by-layer method. A multimodal characterization showed the absence of stratification of the films formed by the alternate deposition of poly(diallyldimethylammonium chloride) and poly(sodium 4-styrenesulfonate). Indeed the final organization might be regarded as three-dimensional solid-supported inter-polyelectrolyte films. The growth mechanism of the multilayers, followed using a quartz crystal microbalance, evidences two different growth trends, which show a dependency on the ionic strength due to its influence onto the polymer conformation. The hydration state does not modify the multilayer growth, but it contributes to the total adsorbed mass of the film. The water associated with the polyelectrolyte films leads to their swelling and plastification. The use of X-ray photoelectron spectroscopy has allowed for deeper insights on the internal structure and composition of the polyelectrolyte multilayers.

5.
Nanotechnology ; 19(22): 225603, 2008 Jun 04.
Article in English | MEDLINE | ID: mdl-21825763

ABSTRACT

Silica-based ZnO-MCM-41 mesoporous nanocomposites with high Zn content (5≤Si/Zn≤50) have been synthesized by a one-pot surfactant-assisted procedure from aqueous solution using a cationic surfactant (CTMABr = cetyltrimethylammonium bromide) as structure-directing agent, and starting from molecular atrane complexes as inorganic hydrolytic precursors. This preparative technique allows optimization of the dispersion of the ZnO nanodomains in the silica walls. The mesoporous nature of the final materials is confirmed by x-ray diffraction (XRD), transmission electron microscopy (TEM) and N(2) adsorption-desorption isotherms. The ZnO-MCM-41 materials show unimodal pore size distributions without blocking of the pore system even for high Zn content. A careful optical spectroscopic study (using x-ray photoelectron spectroscopy (XPS), photoluminescence (PL) and UV-visible spectroscopy) of these materials shows that, irrespective of the Si/Zn ratio, the Zn atoms are organized in well-dispersed, uniform low-defect ZnO nanodomains (radius about 1 nm) and are partially embedded within the silica walls.

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