In order to overcome the hydrophilic problem of aerogels based on soluble polymer, the transition of aerogel composites from hydrophilic to hydrophobic was achieved by grafting 1H, 1H, 2H, ...2H‐Perfluorodecyltrimethoxysilane (FAS). Simply immersing in FAS ethanol solution and then ambient drying, this method is universal and efficient, we successfully achieved the soluble polymer aerogels hydrophobic transition. Taking polyvinyl alcohol (PVOH)/SiO2 as an example, the changes of structure and properties of aerogels before and after modification were characterized in detail. It was proved that FAS was successfully grafted and ethanol evaporation had little effect on the microstructure of aerogel. The resulting aerogels possess very good hydrophobicity, with water contact angle of up to 147.5° (3 wt.% FAS). The aerogel exhibits good stability in maintaining hydrophobicity in a harsh environment, such as in extreme pH and temperature. We introduced a universal method for hydrophobic modification, which is of great significance for the practical application of aerogels.
In this paper, we realized the hydrophilic‐hydrophobic conversion of aerogels, and maintained the hydrophobic effect under strong acid, strong strength, high temperature and ultra‐low temperature.
Background and Aims
Coronavirus disease 2019 (COVID‐19) is a new infectious disease. To reveal the hepatic injury related to this disease and its clinical significance, we conducted a multicenter ...retrospective cohort study that included 5,771 adult patients with COVID‐19 pneumonia in Hubei Province.
Approach and Results
We reported the distributional and temporal patterns of liver injury indicators in these patients and determined their associated factors and death risk. Longitudinal liver function tests were retrospectively analyzed and correlated with the risk factors and death. Liver injury dynamic patterns differed in alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total bilirubin (TBIL). AST elevated first, followed by ALT, in severe patients. ALP modestly increased during hospitalization and largely remained in the normal range. The fluctuation in TBIL levels was mild in the non‐severe and the severe groups. AST abnormality was associated with the highest mortality risk compared with the other indicators of liver injury during hospitalization. Common factors associated with elevated liver injury indicators were lymphocyte count decrease, neutrophil count increase, and male gender.
Conclusion
The dynamic patterns of liver injury indicators and their potential risk factors may provide an important explanation for the COVID‐19‐associated liver injury. Because elevated liver injury indicators, particularly AST, are strongly associated with the mortality risk, our study indicates that these parameters should be monitored during hospitalization.
Type 2 diabetes (T2D) is a major comorbidity of COVID-19. However, the impact of blood glucose (BG) control on the degree of required medical interventions and on mortality in patients with COVID-19 ...and T2D remains uncertain. Thus, we performed a retrospective, multi-centered study of 7,337 cases of COVID-19 in Hubei Province, China, among which 952 had pre-existing T2D. We found that subjects with T2D required more medical interventions and had a significantly higher mortality (7.8% versus 2.7%; adjusted hazard ratio HR, 1.49) and multiple organ injury than the non-diabetic individuals. Further, we found that well-controlled BG (glycemic variability within 3.9 to 10.0 mmol/L) was associated with markedly lower mortality compared to individuals with poorly controlled BG (upper limit of glycemic variability exceeding 10.0 mmol/L) (adjusted HR, 0.14) during hospitalization. These findings provide clinical evidence correlating improved glycemic control with better outcomes in patients with COVID-19 and pre-existing T2D.
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•A cohort of 7,337 COVID-19 patients with or without diabetes was retrospectively studied•Diabetes status increased the need for medical interventions during COVID-19•Diabetes status increased the mortality risk of patients with COVID-19•Well-controlled blood glucose correlated with improved outcomes in infected patients
Type 2 diabetes (T2D) correlates with a worse outcome for COVID-19. Here, Zhu et al. show that among ∼7,300 cases of COVID-19, T2D is associated with a higher death rate, but diabetics with better controlled blood glucose die at a lower rate than diabetics with poorly controlled blood glucose.
Statins are lipid-lowering therapeutics with favorable anti-inflammatory profiles and have been proposed as an adjunct therapy for COVID-19. However, statins may increase the risk of SARS-CoV-2 viral ...entry by inducing ACE2 expression. Here, we performed a retrospective study on 13,981 patients with COVID-19 in Hubei Province, China, among which 1,219 received statins. Based on a mixed-effect Cox model after propensity score-matching, we found that the risk for 28-day all-cause mortality was 5.2% and 9.4% in the matched statin and non-statin groups, respectively, with an adjusted hazard ratio of 0.58. The statin use-associated lower risk of mortality was also observed in the Cox time-varying model and marginal structural model analysis. These results give support for the completion of ongoing prospective studies and randomized controlled trials involving statin treatment for COVID-19, which are needed to further validate the utility of this class of drugs to combat the mortality of this pandemic.
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•Statin treatment among 13,981 patients with COVID-19 was retrospectively studied•Statin use in this cohort was associated with a lower risk of all-cause mortality•Adding an ACE inhibitor or an ARB did not affect statin-associated outcome in the cohort•The benefit of statins among this cohort may be due to immunomodulatory benefits
Statins have anti-inflammatory benefits and were suggested as an adjunct therapy for COVID-19. But statins may increase the expression of ACE2, the receptor for SARS-CoV-2. Here, Zhang et al. retrospectively analyzed 13,981 COVID-19 cases and found that in-hospital statin use is associated with a lower risk of all-cause mortality.
Sensing of viral RNA by the cytosolic receptors RIG-I and melanoma differentiation-associated gene 5 (MDA5) leads to innate antiviral response. How RIG-I and MDA5 are dynamically regulated in innate ...antiviral response is not well understood. Here, we show that TRIM38 positively regulates MDA5- and RIG-I-mediated induction of downstream genes and acts as a SUMO E3 ligase for their dynamic sumoylation at K43/K865 and K96/K888, respectively, before and after viral infection. The sumoylation of MDA5 and RIG-I suppresses their K48-linked polyubiquitination and degradation in uninfected or early-infected cells. Sumoylation of the caspase recruitment domains of MDA5 and RIG-I is also required for their dephosphorylation by PP1 and activation upon viral infection. At the late phase of viral infection, both MDA5 and RIG-I are desumoylated by SENP2, resulting in their K48-linked polyubiquitination and degradation. These findings suggest that dynamic sumoylation and desumoylation of MDA5 and RIG-I modulate efficient innate immunity to RNA virus and its timely termination.
A carbazole‐containing difluoroboron β‐diketonate complex (BCZ), which shows strong fluorescence in both the solid state and in organic solutions, is reported. The crystalline materials of BCZ ...obtained from different solvents display different emission colors. Single‐crystal analysis reveals that the enhanced overlap between adjacent molecules induces increased excited‐state delocalization and is responsible for the variation of the emission colors from yellow to red. The emission colors of the materials are effectively tuned by external stimuli such as grinding, heating, and solvent vapor. The powder X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and 1H NMR studies on materials of BCZ reveal that the thermochromic properties of BCZ are closely related to the removal of solvent molecules from the crystalline powders upon heating. Moreover, uniform 1D microstructures of BCZ obtained by solvent exchange in solution exhibit optical waveguide property with low optical loss.
A solid‐state fluorescent material based on carbazole‐containing BF2bdk complex (BCZ) is reported. The emission colors of BCZ in solid state are dependent on its molecular packing modes and are successfully tuned upon external stimuli, such as grinding, heating, and solvent fuming. The uniform microrod of BCZ exhibits optical waveguide properties with low optical loss.
During viral infection, sensing of cytosolic DNA by the cyclic GMP-AMP synthase (cGAS) activates the adaptor protein STING and triggers an antiviral response. Little is known about the mechanisms ...that determine the kinetics of activation and deactivation of the cGAS-STING pathway, ensuring effective but controlled innate antiviral responses. Here we found that the ubiquitin ligase Trim38 targets cGas for sumoylation in uninfected cells and during the early phase of viral infection. Sumoylation of cGas prevented its polyubiquitination and degradation. Trim38 also sumoylated Sting during the early phase of viral infection, promoting both Sting activation and protein stability. In the late phase of infection, cGas and Sting were desumoylated by Senp2 and subsequently degraded via proteasomal and chaperone-mediated autophagy pathways, respectively. Our findings reveal an essential role for Trim38 in the innate immune response to DNA virus and provide insight into the mechanisms that ensure optimal activation and deactivation of the cGAS-STING pathway.
•Trim38 deficiency enhances susceptibility to DNA virus infection•Sumoylation of cGas and Sting promotes their stability during early infection•In the late phase of infection, cGas and Sting are desumoylated by Senp2•Desumoylation of cGas and Sting leads to their degradation by different mechanisms
Hu et al. show that sumoylation of the DNA sensor cGas and the adaptor Sting by Trim38 and their subsequent desumoylation by Senp2 ensure an efficient triggering of the cGAS-STING pathway in the early phase of DNA virus infection, as well as its timely termination upon resolution of infection.
Cyclic GMP-AMP synthase (cGAS) senses double-strand (ds) DNA in the cytosol and then catalyzes synthesis of the second messenger cGAMP, which activates the adaptor MITA/STING to initiate innate ...antiviral response. How cGAS activity is regulated remains enigmatic. Here, we identify ZCCHC3, a CCHC-type zinc-finger protein, as a positive regulator of cytosolic dsDNA- and DNA virus-triggered signaling. We show that ZCCHC3-deficiency inhibits dsDNA- and DNA virus-triggered induction of downstream effector genes, and that ZCCHC3-deficient mice are more susceptible to lethal herpes simplex virus type 1 or vaccinia virus infection. ZCCHC3 directly binds to dsDNA, enhances the binding of cGAS to dsDNA, and is important for cGAS activation following viral infection. Our results suggest that ZCCHC3 is a co-sensor for recognition of dsDNA by cGAS, which is important for efficient innate immune response to cytosolic dsDNA and DNA virus.
Recognition of viral RNA by the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) initiates innate antiviral immune response. How the binding of viral RNA to and activation of the RLRs are ...regulated remains enigmatic. In this study, we identified ZCCHC3 as a positive regulator of the RLRs including RIG-I and MDA5. ZCCHC3 deficiency markedly inhibited RNA virus-triggered induction of downstream antiviral genes, and ZCCHC3-deficient mice were more susceptible to RNA virus infection. ZCCHC3 was associated with RIG-I and MDA5 and functions in two distinct processes for regulation of RIG-I and MDA5 activities. ZCCHC3 bound to dsRNA and enhanced the binding of RIG-I and MDA5 to dsRNA. ZCCHC3 also recruited the E3 ubiquitin ligase TRIM25 to the RIG-I and MDA5 complexes to facilitate its K63-linked polyubiquitination and activation. Thus, ZCCHC3 is a co-receptor for RIG-I and MDA5, which is critical for RLR-mediated innate immune response to RNA virus.
•ZCCHC3 mediates viral RNA-triggered innate immune response•ZCCHC3 binds to viral RNA•ZCCHC3 acts as a co-receptor for RIG-I and MDA5•ZCCHC3 mediates polyubiquitination and activation of RIG-I and MDA5 by TRIM25
Recognition of viral RNA by RIG-I-like receptors (RLRs) initiates innate antiviral response. Lian et al. demonstrate that ZCCHC3 is a co-receptor for RLRs, thereby acting as an important modulator of innate antiviral response.
This note is concerned with the stability analysis of linear systems with a time-varying delay, where the delay is assumed to be a periodically varying bounded function with restricted derivatives. ...Combining the allowable delay set (ADS) definition and the region partitioning technique, an ADS partitioning approach is proposed, and then by with aid of this approach, a novel Lyapunov–Krasovskii functional (LKF), namely delay-set-partition-based (DSPB) LKF, is developed. Compared with the previous LKF method, the main advantage of the DSPB LKF lies in allowing the considered system to construct its own LKF in each sub-ADS. By utilizing the proposed LKF, less conservative stability criteria are derived. Finally, two simulation examples are provided to verify the effectiveness and superiority of the proposed method.
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