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We present a fast, reliable and easy to scale-up colorimetric sensor based on gold nanoparticles (AuNPs) to detect the sequences coding for the RdRp, E, and S proteins of SARS-CoV-2. The optimization of the system (so-called "the sensor") includes the evaluation of different sizes of nanoparticles, sequences of oligonucleotides and buffers. It is stable for months without any noticeable decrease in its activity, allowing the detection of SARS-CoV-2 sequences by the naked eye in 15 min. The efficiency and selectivity of detection, in terms of significative colorimetric changes in the solution upon target recognition, are qualitatively (visually) and quantitatively (absorbance measurements) assessed using synthetic samples and samples derived from infected cells and patients. Furthermore, an easy and affordable amplification approach is implemented to increase the system's sensitivity for detecting high and medium viral loads (≥10 3 - 10 4 viral RNA copies/μl) in patient samples. The whole process (amplification and detection) takes 2.5 h. Due to the ease of use, stability and minimum equipment requirements, the proposed approach can be a valuable tool for the detection of SARS-CoV-2 at facilities with limited resources., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Membrane pores can significantly alter not only the permeation dynamics of biological membranes but also their elasticity. Large membrane pores able to transport macromolecular contents represent an interesting model to test theoretical predictions that assign active-like (non-equilibrium) behavior to the permeability contributions to the enhanced membrane fluctuations existing in permeable membranes [Maneville et al. Phys. Rev. Lett. 82, 4356 (1999)]. Such high-amplitude active contributions arise from the forced transport of solvent and solutes through the open pores, which becomes even dominant at large permeability. In this paper, we present a detailed experimental analysis of the active shape fluctuations that appear in highly permeable lipid vesicles with large macromolecular pores inserted in the lipid membrane, which are a consequence of transport permeability events occurred in an osmotic gradient. The experimental results are found in quantitative agreement with theory, showing a remarkable dependence with the density of membrane pores and giving account of mechanical compliances and permeability rates that are compatible with the large size of the membrane pore considered. The presence of individual permeation events has been detected in the fluctuation time-series, from which a stochastic distribution of the permeation events compatible with a shot-noise has been deduced. The non-equilibrium character of the membrane fluctuations in a permeation field, even if the membrane pores are mere passive transporters, is clearly demonstrated. Finally, a bio-nano-technology outlook of the proposed synthetic concept is given on the context of prospective uses as active membrane DNA-pores exploitable in gen-delivery applications based on lipid vesicles., (Copyright © 2017 Elsevier B.V. All rights reserved.)

We compared the rate and extent of anidulafungin's and fluconazole's activity in neutropenic and non-neutropenic mice with Candida albicans invasive candidiasis. In immunocompetent mice, anidulafungin significantly improved survival vs. controls and fluconazole, and significant reductions in (1→3)-β-D-glucan and fungal burden were observed. In neutropenic animals, the highest doses of anidulafungin (5 mg/kg) and fluconazole (10 mg/kg) also improved survival and reduced fungal burden. However, there were no differences in survival between these antifungals as anidulafungin's activity was attenuated in this model. These results demonstrate that the extent of anidulafungin in vivo efficacy may be dependent on host immune status., (© 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.)

Extended interval dosing of the echinocandins has been suggested as a potential strategy to overcome the need for daily intravenous administration. This study evaluated the therapeutic and prophylactic efficacy of single doses of aminocandin, a new echinocandin in preclinical development, in a murine model of invasive candidiasis. For therapy, groups of mice were infected with Candida albicans, followed by a single dose of aminocandin (1-15 mg/kg) or placebo (mannitol 5% w/v) administered 1 day after inoculation. As prophylaxis, mice were given a single dose (5 or 30 mg/kg) of aminocandin, caspofungin, or placebo at increasing intervals between dose and inoculation. In both treatment and prophylaxis studies, survival was assessed at 21 days post-inoculation. The reduction in fungal burden was assessed in kidney tissue on day 8 post-inoculation. For treatment, single doses of aminocandin of >/=2.5 mg/kg prolonged survival significantly. In addition, the two doses evaluated for reductions in fungal burden (5 and 15 mg/kg) revealed fungicidal activity. As prophylaxis, both aminocandin and caspofungin 5 and 30 mg/kg prolonged survival when given 7 days before inoculation. Aminocandin and caspofungin 30 mg/kg were both able to prolong survival when the interval between dose and inoculation was increased to 10 days. When this interval was extended to 14 days, only aminocandin 30 mg/kg prolonged survival and reduced fungal burden. These results demonstrate that single doses of aminocandin are effective as treatment and prophylaxis, and suggest that extended interval dosing may be a useful strategy for treating invasive candidiasis.

The adsorption and desorption of radon on five types of activated carbon and the effect of various airborne contaminants on the adsorption process was studied, the dynamic adsorption coefficient for the carbon samples tested was found to range from 2.4 +/- 0.2 to 7.1 +/- 0.71 g-1. Iso-octane was found to reduce the dynamic adsorption coefficient significantly.