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The article cites a research study that examines the regulation of type I interferon signaling pathway by deubiquitinase enzyme (DUB) family during antiviral responses. It is said that the innate immune response conferred by type I interferons needs to be controlled to avoid immunopathology. The study found that the expression of a large fraction of DUBs underwent complex temporal alteration.

Phthalates and phthalate alternatives are semivolatile organic compounds (SVOCs) present in many PVC products as plasticizers to enhance product performance. Knowledge of the mass-transfer parameters, including the equilibrium concentration in the air in contact with the product surface (y0), will greatly improve the ability to estimate the emission rate of SVOCs from these products and to assess human exposure. The objective of this study was to measure y0 for different PVC products and to evaluate its relationship with the material-phase concentrations (C0). Also, C0 and y0 data from other sources were included, resulting in a substantially larger data set (Ntotal = 34, T = 25 °C) than found in previous studies. The results show that the material/gas equilibrium relationship does not follow Raoult's law and that therefore the assumption of an ideal solution is invalid. Instead, Henry's law applies, and the Henry's law constant for all target SVOCs consists of the respective pure liquid vapor pressure and an activity coefficient γ, which accounts for the nonideal nature of the solution. For individual SVOCs, a simple partitioning relationship exists, but Henry's law is more generally applicable and will be of greater value in rapid exposure assessment procedures. [ABSTRACT FROM AUTHOR]

Phthalates and alternative plasticizers are semivolatile organic compounds (SVOCs), an important class of indoor pollutants that may have significant adverse effects on human health. Unfortunately, models that predict emissions of and the resulting exposure to SVOCs have substantial uncertainties. One reason is that the characteristics governing emissions, transport, and exposure are usually strongly dependent on vapor pressure. Furthermore, available data for phthalates exhibit significant variability, and vapor pressures for the various alternatives are usually unavailable. For these reasons, a new approach based on modeling of the evaporation process was developed to determine vapor pressures of phthalates and alternate plasticizers. A laminar flow forced convection model was used in the design of a partial saturator (PS) tube. The mass transfer mechanisms in the PS tube are accurately modeled and enable the determination of vapor pressure even when the carrier gas is not completely saturated, avoiding the complicated procedure to establish vapor saturation. The measured vapor pressures ranged from about 10-2 to 10-7 Pa. Compared to the traditional gas saturation method, the model-based approach is advantageous in terms of both predictability and simplicity. The knowledge provides new insight into experimental design and a sound basis for further method development. [ABSTRACT FROM AUTHOR]

Fluorotelomer alcohols (FTOHs) are one important subgroup of perfluorinated compounds (PFCs), yet Henry's law constant (KH) of FTOHs, which is also known as the air–water partition coefficient, remains poorly understood with a wide range of reported values. This study measured the KHof FTOHs from (309.6 to 334.2) K using the integrated gas-stripping method (IGS) for the first time, which has a lower surface-to-volume ratio comparing to the headspace method (HS). Two different materials, namely, stainless steel and glass, were chosen for constructing the stripping vessels. Results indicated significantly stronger adsorption of long-chained FTOHs on glass surface, which led to a significant bias in KHderivation. KHvalues extrapolated to 298 K of 4:2, 6:2, 8:2, and 10:2 FTOH, using a stainless steel vessel, showed no linear increase. A similar tendency was also reported by other groups using the HS approach. The unique molecular geometry of FTOHs was suspected to be responsible for the unusual tendency observed and false predications by modeling software including SPARC and EPI Suite. Compared with HS results reported by others, the KHvalues obtained in this study were higher. The discrepancy might be mainly due to the different extent of surface adsorption engaged in the two approaches. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global crisis. There is no therapeutic treatment specific for COVID-19. It is highly desirable to identify potential antiviral agents against SARS-CoV-2 from existing drugs available for other diseases and thus repurpose them for treatment of COVID-19. In general, a drug repurposing effort for treatment of a new disease, such as COVID-19, usually starts from a virtual screening of existing drugs, followed by experimental validation, but the actual hit rate is generally rather low with traditional computational methods. Here we report a virtual screening approach with accelerated free energy perturbation-based absolute binding free energy (FEP-ABFE) predictions and its use in identifying drugs targeting SARS-CoV-2 main protease (Mpro). The accurate FEP-ABFE predictions were based on the use of a restraint energy distribution (RED) function, making the practical FEP-ABFE-based virtual screening of the existing drug library possible. As a result, out of 25 drugs predicted, 15 were confirmed as potent inhibitors of SARS-CoV-2 Mpro. The most potent one is dipyridamole (inhibitory constant Ki = 0.04 µM)which has shown promising therapeutic effects in subsequently conducted clinical studies for treatment of patients with COVID-19. Additionally, hydroxychloroquine (Ki = 0.36 µM) and chloroquine (Ki = 0.56 µM) were also found to potently inhibit SARS-CoV-2 Mpro. We anticipate that the FEP-ABFE prediction-based virtual screening approach will be useful in many other drug repurposing or discovery efforts. [ABSTRACT FROM AUTHOR]