TiO₂ Photocatalytic Cyclization Reactions for the Syntheses of Aryltetralones

This work focuses on a new strategy to overcome the overoxidation in heterogeneous TiO₂ photocatalysis and to realize high-efficiency photosynthesis. We demonstrate that TiO₂ photocatalysis can integrate C–C and CO formation in a tandem manner to achieve efficient oxidative cyclization for the syntheses of aryltetralones. This protocol does not need any additive besides the inexpensive and/or recyclable TiO₂, O₂, and (solar) light. High yields with excellent diastereoselectivities are obtained for a wide scope of electron-rich substrates. Our findings demonstrate that in contrast to the conventional overoxidation, as long as the radical cations possess sufficient reactivity toward nucleophilic addition, single-electron transfer processes in TiO₂ photocatalysis can be developed into a powerful tool to construct C–C bonds and even strained carbon rings

Design and Control of Extractive Dividing Wall Column for Separating Benzene/Cyclohexane Mixtures

This paper considers the design and control of the separation of benzene and cyclohexane process via extractive distillation in a dividing wall column. To aid the separation, furfural is used as the heavy boiling entrainer. The optimal flow sheet with minimum energy requirements has been established using the multiobjective genetic algorithm with constrains. Three control strategies are proposed: the basic control strategy uses four composition controllers, and two improved control strategies with and without vapor split ratio use temperature controllers that are more practical in application than the basic control strategy. The dynamic simulations reveal that the three control strategies can object to the feed disturbances well. The dynamic responses of two improved control structures show that vapor split ratio as a manipulated variable can maintain the product purities at their set points when a feed disturbance is introduced

Transition of Phase Structures in Mixtures of Lysine and Fatty Acids

Aggregation behaviors of the mixtures of lysine and fatty acids (FAs) with different chain lengths in aqueous solutions were investigated, and the self-assembled structural transition was determined in detail. Aggregates including micelles, vesicles, sponge structures, and fibers were observed by varying the compositions and the chain length of fatty acids. The sponge phase found in mixtures of octanoic acid and lysine was determined by freeze fracture-transmission electron microscope (FF-TEM). Circular dichroism (CD) signals were detected in the self-assembled structures due to the chirality of lysine molecules. The rheological properties of samples consisting of different aggregates formed by mixtures of lysine and fatty acids were measured, which provided the controlling factor of the chain length. The combined effect of noncovalent interactions including electrostatic interactions, hydrogen bonding, and hydrophobicity is supposed to be responsible for the aggregation behaviors, in which the hydrogen bonding acts as the main driving force in the self-assembled process

Covalent Assembly of Heterosequenced Macrocycles and Molecular Cages through Orthogonal Dynamic Covalent Chemistry (ODCC)

Shape-persistent heterosequenced 2-D macrocycles and 3-D molecular cages have been prepared in one pot from two or three different monomers, through orthogonal dynamic covalent chemistry using dynamic imine and olefin metathesis

Design and Control of Different Pressure Thermally Coupled Reactive Distillation for Methyl Acetate Hydrolysis

Thermally coupled distillation is designed to reduce energy requirements and achieve environmental benefits in chemical engineering development processes. In this study an attractive different pressure thermally coupled reactive distillation (DPTCRD) process was proposed for the hydrolysis of methyl acetate, and the DPTCRD process was optimized to evaluate its economic feasibility. The calculation results clearly demonstrated that the total annual cost of this thermally coupled sequence can be saved by 7.49% and its exergy consumption is reduced by 40.07% compared with conventional reactive distillation. In addition, the controllability of this promising sequence was evaluated, and the dynamic results showed that the system with improved control structure can maintain stable operation and handle large feed upsets effectively

Table1_The effect of the cyclic GMP-AMP synthase-stimulator of interferon genes signaling pathway on organ inflammatory injury and fibrosis.pdf

The cyclic GMP-AMP synthase-stimulator of interferon genes signal transduction pathway is critical in innate immunity, infection, and inflammation. In response to pathogenic microbial infections and other conditions, cyclic GMP-AMP synthase (cGAS) recognizes abnormal DNA and initiates a downstream type I interferon response. This paper reviews the pathogenic mechanisms of stimulator of interferon genes (STING) in different organs, including changes in fibrosis-related biomarkers, intending to systematically investigate the effect of the cyclic GMP-AMP synthase-stimulator of interferon genes signal transduction in inflammation and fibrosis processes. The effects of stimulator of interferon genes in related auto-inflammatory and neurodegenerative diseases are described in this article, in addition to the application of stimulator of interferon genes-related drugs in treating fibrosis.</p

Engineered Split-TET2 Enzyme for Inducible Epigenetic Remodeling

The Ten-eleven translocation (TET) family of 5-methylcytosine (5mC) dioxygenases catalyze the conversion of 5mC into 5-hydroxymethylcytosine (5hmC) and further oxidized species to promote active DNA demethylation. Here we engineered a split-TET2 enzyme to enable temporal control of 5mC oxidation and subsequent remodeling of epigenetic states in mammalian cells. We further demonstrate the use of this chemically inducible system to dissect the correlation between DNA hydroxymethylation and chromatin accessibility in the mammalian genome. This chemical-inducible epigenome remodeling tool will find broad use in interrogating cellular systems without altering the genetic code, as well as in probing the epigenotype–phenotype relations in various biological systems

Calcium Regulation of Hemorrhagic Fever Virus Budding: Mechanistic Implications for Host-Oriented Therapeutic Intervention

<div><p>Hemorrhagic fever viruses, including the filoviruses (Ebola and Marburg) and arenaviruses (Lassa and Junín viruses), are serious human pathogens for which there are currently no FDA approved therapeutics or vaccines. Importantly, transmission of these viruses, and specifically late steps of budding, critically depend upon host cell machinery. Consequently, strategies which target these mechanisms represent potential targets for broad spectrum host oriented therapeutics. An important cellular signal implicated previously in EBOV budding is calcium. Indeed, host cell calcium signals are increasingly being recognized to play a role in steps of entry, replication, and transmission for a range of viruses, but if and how filoviruses and arenaviruses mobilize calcium and the precise stage of virus transmission regulated by calcium have not been defined. Here we demonstrate that expression of matrix proteins from both filoviruses and arenaviruses triggers an increase in host cytoplasmic Ca²⁺ concentration by a mechanism that requires host Orai1 channels. Furthermore, we demonstrate that Orai1 regulates both VLP and infectious filovirus and arenavirus production and spread. Notably, suppression of the protein that triggers Orai activation (Stromal Interaction Molecule 1, STIM1) and genetic inactivation or pharmacological blockade of Orai1 channels inhibits VLP and infectious virus egress. These findings are highly significant as they expand our understanding of host mechanisms that may broadly control enveloped RNA virus budding, and they establish Orai and STIM1 as novel targets for broad-spectrum host-oriented therapeutics to combat these emerging BSL-4 pathogens and potentially other enveloped RNA viruses that bud via similar mechanisms.</p></div

Pharmacological effect of Synta66 and 2-APB on egress of filovirus VLPs.

<p>HEK293T expressing eVP40 (<b>A</b> and <b>B</b>) or mVP40 (<b>C</b> and <b>D</b>) were treated with indicated concentrations of 2-APB or Synta66. eVP40 and mVP40 levels in cell extracts and VLPs were detected by immunoblot analysis and quantified in VLPs (bar graphs). 2-APB <b>(E)</b> and Synta66 <b>(F)</b> cytotoxicity was assessed with an MTT viability assay under conditions that mimicked those used for the VLP experiments. In all experiments, cellular actin served as a loading control. Relative protein bands densities were normalized to untreated sample densities (0 μM). Plotted values represent the average (+/- S.E.M) of 3–6 independent experiments and were analyzed with either Welch's t-test or Wilcoxon rank-sum test (*p = 0.01, **p = 0.05).</p