Alcoholic hepatitis is a major health and economic burden worldwide. Glucocorticoids (GCs) are the only first-line drugs recommended to treat severe alcoholic hepatitis (sAH), with limited short-term ...efficacy and significant side effects. In this review, I summarize the major benefits and side effects of GC therapy in sAH and the potential underlying mechanisms. The review of the literature and data mining clearly indicate that the hepatic signaling of glucocorticoid receptor (GR) is markedly impaired in sAH patients. The impaired GR signaling causes hepatic down-regulation of genes essential for gluconeogenesis, lipid catabolism, cytoprotection, and anti-inflammation in sAH patients. The efficacy of GCs in sAH may be compromised by GC resistance and/or GC's extrahepatic side effects, particularly the side effects of intestinal epithelial GR on gut permeability and inflammation in AH. Prednisolone, a major GC used for sAH, activates both the GR and mineralocorticoid receptor (MR). When GC non-responsiveness occurs in sAH patients, the activation of MR by prednisolone might increase the risk of alcohol abuse, liver fibrosis, and acute kidney injury. To improve the GC therapy of sAH, the effort should be focused on developing the biomarker(s) for GC responsiveness, liver-targeting GR agonists, and strategies to overcome GC non-responsiveness and prevent alcohol relapse in sAH patients.
Natural gas hydrates (NGH) is one of key future clean energy resources. Its industrialized development will help remit the huge demand of global natural gas, relieve the increasing pressure of the ...environment, and play a vital role in the green sustainable growth of human societies. Based on nearly two decades’ studying on the reservoir characteristics in the South China Sea (SCS) and the knowledge of reservoir system, the China Geological Survey (CGS) conducted the first production test on an optimal target selected in Shenhu area SCS in 2017. Guided by the “three-phase control” exploitation theory which focused on formation stabilization, technologies such as formation fluid extraction, well drilling and completing, reservoir stimulating, sand controlling, environmental monitoring, monitoring and preventing of secondary formation of hydrates were applied. The test lasted for 60 days from May 10th when starting to pump, drop pressure and ignite to well killing on July 9th, with gas production of 3.09×105 m3 in total, which is a world record with the longest continuous duration of gas production and maximal gas yield. This successful test brings a significant breakthrough on safety control of NGH production.
Wearable touch panels, a typical flexible electronic device, can recognize and feed back the information of finger touch and movement. Excellent wearable touch panels are required to accurately and ...quickly monitor the signals of finger movement as well as the capacity of bearing various types of deformation. High‐performance thermistor materials are one of the key functional components, but to date, a long‐standing bottleneck is that inorganic semiconductors are typically brittle while the electrical properties of organic semiconductors are quite low. Herein, a high‐performance flexible temperature sensor is reported by using plastic Ag2S with ultrahigh temperature coefficient of resistance of −4.7% K−1 and resolution of 0.05 K, and rapid response/recovery time of 0.11/0.11 s. Moreover, the temperature sensor shows excellent durability without performance damage or loss during force stimuli tests. In addition, a fully flexible intelligent touch panel composed of a 16 × 10 Ag2S‐film‐based temperature sensor array, as well as a flexible printed circuit board and a deep‐learning algorithm is designed for perceiving finger touch signals in real‐time, and intelligent feedback of Chinese characters and letters on an app. These results strongly show that high‐performance flexible inorganic semiconductors can be widely used in flexible electronics.
A fully flexible intelligent thermal touch panel based on the intrinsically plastic Ag2S semiconductor can well perceive finger touch signals in real‐time and displays intelligent feed back of Chinese characters and letters on an app.
A pandemic of severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) infection broke out all over the world; however, epidemiological data and viral shedding in pediatric patients are limited. ...We conducted a retrospective, multicenter study, and followed‐up with all children from the families with SARS‐CoV‐2 infected members in Zhejiang Province, China. All infections were confirmed by testing the SARS‐CoV‐2 RNA with real‐time reverse transcription PCR method, and epidemiological data between children and adults in the same families were compared. Effect of antiviral therapy was evaluated observationally and fecal‐viral excretion times among groups with different antiviral regiments were compared with Kaplan‐Meier plot. By 29 February 2020, 1298 cases from 883 families were confirmed with SARS‐CoV‐2 infection and 314 of which were families with children. Incidence of infection in child close contacts was significantly lower than that in adult contacts (13.2% vs 21.2%). The mean age of 43 pediatric cases was 8.2 years and mean incubation period was 9.1 days. Forty (93.0%) were family clustering. Thirty‐three children had coronavirus disease 2019 (20 pneumonia) with mild symptoms and 10 were asymptomatic. Fecal SARS‐CoV‐2 RNA detection was positive in 91.4% (32/35) cases and some children had viral excretion time over 70 days. Viral clearance time was not different among the groups treated with different antiviral regiments. No subsequent infection was observed in family contacts of fecal‐viral‐excreting children. Children have lower susceptibility of SARS‐CoV‐2 infection, longer incubation, and fecal‐viral excretion time. Positive results of fecal SARS‐CoV‐2 RNA detection were not used as indication for hospitalization or quarantine.
Highlights
Children had lower susceptibility for SARS‐CoV‐2 infection than adults.
Children had longer incubation period and fecal viral excretion time after infected by SARS‐CoV‐2.
Viral clearance time was not different among the groups treated with different antiviral regiments.
Children had milder clinical symptoms, better clinical outcome, and more common fecal viral excretion.
Positive results of fecal SARS‐CoV‐2 RNA detection are not used as indication for hospitalization or quarantine.
Eleven new 9,19-cycloartane triterpenes (1-9, 11-12) and one undescribed lanostane-type aglycone (10) were identified from the aerial parts of
. The new structures were elucidated by analysis of ...spectroscopic data. Compounds 3-5, 7-9, and 11, without obvious cytotoxicity at 50 μM, were evaluated for inhibiting the mRNA expressions of atherosclerosis-related factors of CD147 (extracellular matrix metalloproteinase inducer, EMMPRIN), matrix metalloproteinase 2 (MMP-2) and MMP-9 in phorbol-12-myristate-13-acetate (PMA) induced Human monocytic THP-1 cells by using a quantitative real-time PCR method (q-PCR). Among them, aglycones 7 and 8 showed potent activities, whereas all tested glycosides were inactive. Compounds 7 and 8 suppressed the mRNA expression of CD147 in a dose-dependent manner, with an IC
value of 3.38 ± 0.27 μM and 8.25 ± 0.33 μM, respectively. Besides, 7 dose-related down-regulated the mRNA expression of MMP-2, and MMP-9, having an IC
value of 6.32 ± 0.31 μM and 11.57 ± 0.23 μM, respectively. Meanwhile, 8 at 10 μM reduced the mRNA expression of MMP-2 and MMP-9 by 35% and 25%, respectively. Significantly, the migration ability of the induced THP-1 cells was potently and dose-dependently inhibited by 7, with an IC
value of 5.87 ± 0.27 μM.
With the increasing concerns about chemical pollution and sustainability of resources, among the significant challenges facing synthetic chemists are the development and application of elegant and ...efficient methods that enable the concise synthesis of natural products, drugs, and related compounds in a step-, atom- and redox-economic manner. One of the most effective ways to reach this goal is to implement reaction cascades that allow multiple bond-forming events to occur in a single vessel. This Account documents our progress on the rational design and strategic application of asymmetric catalytic cascade reactions in constructing diverse scaffolds and synthesizing complex chiral molecules. Our research is aimed at developing robust cascade reactions for the systematic synthesis of a range of interesting molecules that contain structural motifs prevalent in natural products, pharmaceuticals, and biological probes. The strategies employed to achieve this goal can be classified into three categories: bifunctional base/Brønsted acid catalysis, covalent aminocatalysis/N-heterocyclic carbene catalysis, and asymmetric organocatalytic relay cascades. By the use of rationally designed substrates with properly reactive sites, chiral oxindole, chroman, tetrahydroquinoline, tetrahydrothiophene, and cyclohexane scaffolds were successfully assembled under bifunctional base/Brønsted acid catalysis from simple and readily available substances such as imines and nitroolefins. We found that some of these reactions are highly efficient since catalyst loadings as low as 1 mol % can promote the multistep sequences affording complex architectures with high stereoselectivities and yields. Furthermore, one of the bifunctional base/Brønsted acid-catalyzed cascade reactions for the synthesis of chiral cyclohexanes has been used as a key step in the construction of the tetracyclic core of lycorine-type alkaloids and the formal synthesis of α-lycorane. Guided by the principles of covalent aminocatalysis and N-heterocyclic carbene catalysis, we synthesized chiral piperidine, indole, and cyclobutane derivatives. The synthesis of chiral cyclobutanes and pyrroloindolones showed unprecedented reactivity of substrates and catalysts. The development of the strategy of asymmetric organocatalytic relay cascades has provided a useful tool for the controlled synthesis of specific diastereomers in complex molecules. This Account gives a panoramic view and the logic of our research on the design, development, and applications of asymmetric catalytic cascade reactions that will potentially provide useful insights into exploring new reactions.
New BN‐heterocyclic compounds have been found to undergo double arene photoelimination, forming rare yellow fluorescent BN‐pyrenes that contain two BN units. Most significant is the discovery that ...the double arene elimination can also be driven by excitons generated electrically within electroluminescent (EL) devices, enabling the in situ solid‐state conversion of BN‐heterocycles to BN‐pyrenes and the use of BN‐pyrenes as emitters for EL devices. The in situ exciton‐driven elimination (EDE) phenomenon has also been observed for other BN‐heterocycles.
Arene elimination reactions of BN‐heterocycles (A) in an electroluminescent device result in the in situ formation of BN‐pyrenes (B) and BN‐phenanthrenes. This is a novel approach to the creation of functional EL devices.
•Heterostructured p-CuO/n-SnO2 core-shell NWs with precisely controlled shell thickness were synthesized by ALD technique.•The p-CuO/n-SnO2 core-shell NW structured gas sensors with 24 nm SnO2 shell ...layer exhibited enhanced sensing performance.•The well-structured core-shell NWs also have excellent selectivity for HCHO.
Highly sensitive and selective gas sensors based on heterostructured p-CuO/n-SnO2 core-shell nanowires (NWs) with precisely controlled shell thickness were synthesized through a sequential process combining a solution processing and atomic layer deposition. The gas sensing devices were fabricated on micro-electromechanical systems, which has triggered great research interest for low power consumption and highly integrated design. The designed p-CuO/n-SnO2 core-shell NW structured gas sensors exhibited superior gas sensing performance, which is closely related to the thickness of the SnO2 shell. Specifically, p-CuO/n-SnO2 core-shell NWs with a 24 nm thick SnO2 shell displayed a high sensitivity (Ra/Rg) of 2.42, whose rate of resistance change (i.e. 1.42) is 3 times higher than the pristine CuO NW sensor when detecting 50 ppm formaldehyde (HCHO) at 250 °C. The enhanced gas sensing performance could be attributed to the formation of p-n heterojunction which was revealed by specific band alignment and the heterojunction-depletion model. Besides, the well-structured p-CuO/n-SnO2 core-shell NWs achieved excellent selectivity for HCHO from commonly occurred reducing gases. In a word, such heterostructured p-CuO/n-SnO2 core-shell NW gas sensors demonstrate a feasible approach for enhanced sensitive and selective HCHO detection.
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