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Coronavirus 2019 (COVID‐19) has caused violent fluctuation in stock markets, and led to heated discussion in stock forums. The rise and fall of any specific stock is influenced by many other stocks and emotions expressed in forum discussions. Considering the transmission effect of emotions, we propose a new Textual Multiple Auto Regressive Moving Average (TM‐ARMA) model to study the impact of COVID‐19 on the Chinese stock market. The TM‐ARMA model contains a new cross‐textual term and a new cross‐auto regressive (AR) term that measure the cross impacts of textual emotions and price fluctuations, respectively, and the adjacent matrix which measures the relationships among stocks is updated dynamically. We compute the textual sentiment scores by an emotion dictionary‐based method, and estimate the parameter matrices by a maximum likelihood method. Our dataset includes the textual posts from the Eastmoney Stock Forum and the price data for the constituent stocks of the FTSE China A50 Index. We conduct a sliding‐window online forecast approach to simulate the real‐trading situations. The results show that TM‐ARMA performs very well even after the attack of COVID‐19. [ABSTRACT FROM AUTHOR]

Cuproptosis is a very newly recognized regulated cell death modality that is distinct from known death mechanisms and shows enormous prospect in cancer treatment. However, its efficacy is copper‐dependent and restricted by strictly regulated copper metabolism. Herein, a novel copper/iron hybrid hollow amorphous metal organic framework (HaMOF) is developed as an oxidative stress amplifier and copper/iron metabolic disrupter for synergistic cuproptosis/ferroptosis/apoptosis anticancer therapy. The HaMOF is fabricated from Cu2+, 3,3′‐dithiobis(propionohydrazide) and Fe3+ via an unsaturated coordination‐etching integration strategy, and then doxorubicin is loaded followed by surface decoration with hyaluronan. The obtained DOX@Fe/CuTH exhibits tumor microenvironment‐triggered catalytic therapeutic property, wherein it can amplify cellular oxidative stress by simultaneously boosting H2O2 production and depleting glutathione. Moreover, it can cause mitochondrial dysfunction and downregulate the expressions of copper transporter ATP7A and iron transporter FPN 1, thereby leading to metabolic disorders and high retentions of copper/iron in cytoplasm for •OH generation. The overloaded Cu2+ can cause lipoylated protein dihydrolipoamide S‐acetyltransferase aggregation and lead to cellular cuproptosis. Collectively, both augmented oxidative stress and overloaded copper/iron induce potent ferroptosis, which synergizes with cuproptosis and DOX‐mediated apoptosis to efficiently suppress tumor growth. This bimetallic hollow nanoplatform provides a new therapeutic modality paradigm to boost cuproptosis‐related therapies. [ABSTRACT FROM AUTHOR]

5‐(2‐Oxopropylideneamino)‐6‐d‐ribitylaminouracil (5‐OP‐RU) is a natural product formed during bacterial synthesis of vitamin B2. It potently activates mucosal associated invariant T (MAIT) cells and has immunomodulatory, inflammatory, and anticancer properties. This highly polar and unstable compound forms a remarkably stable Schiff base with a lysine residue in major histocompatibility complex class I–related protein (MR1) expressed in antigen‐presenting cells. Inspired by the importance of the ribityl moiety of 5‐OP‐RU for binding to both MR1 and the T cell receptor (TCR) on MAIT cells, each OH was removed in silico. DFT calculations and MD simulations revealed a very stable hydrogen bond between the C3′−OH and uracil N1H, which profoundly restricts flexibility and positioning of each ribityl‐OH, potentially impacting their interactions with MR1 and TCR. By using deoxygenation strategies and kinetically controlled imine formation, four monodeoxyribityl and four monohydroxyalkyl analogues of 5‐OP‐RU were synthesised as new tools for probing T cell activation mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: We study a class of three‐dimensional continuous phase coexistence models, and show that, under different symmetry assumptions on the potential, the large‐scale behavior of such models near a bifurcation point is described by the dynamical Φ 3 p models for p ∊ {2,3,4}. This result is specific to space dimension 3 and does not hold in dimension 2. © 2018 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Immunotherapy shows great promise in the treatment of hepatocellular carcinoma (HCC), however, the low response rate of HCC patients to immunotherapy caused by inadequately immunogenic and immunosuppressive tumor microenvironment (TME) is a huge challenge. Herein, a donut‐like multifunctional polysaccharide nanoplatform (GH‐PID) is constructed from doxorubicin/aldehyde hyaluronan nanoring, indocyanine green/hydroxyethyl chitosan nanocomplex, and HCC‐bitargeted galactosamine‐hyaluronan conjugate via a facile self‐assembly process. The GH‐PID nanodonuts exhibit excellent HCC‐targeted ability and synergetic photochemotherapy effect with a coefficient index of about 0.44. Moreover, near infrared laser‐irradiated GH‐PID nanodonuts show robust therapeutic efficacy in HCC mouse models by virtue of photochemotherapy‐augmented immunogenic cell death (ICD) effect. The remarkable ICD in combination with programmed death‐1 antibody efficiently eradicates primary tumors and inhibits distant tumor growth and lung metastasis of HCC by maturing dendritic cells, increasing CD8+ T cell infiltration, suppressing the expansion and trafficking of immunosuppressive myeloid‐derived suppressor cells, and ameliorating immunosuppressive TME. This study provides a facile and versatile strategy to construct polysaccharide nanodonuts integrating multifunctionality and highly efficient HCC‐targeted ability, and the nanodonuts‐based ICD inducer holds great promise for potentiating systemic antitumor immunity and programmed death‐1/programmed death‐ligand 1 blockade efficacy. [ABSTRACT FROM AUTHOR]

Dynemicin is an enediyne natural product from Micromonospora chersina ATCC53710. Access to the biosynthetic gene cluster of dynemicin has enabled the in vitro study of gene products within the cluster to decipher their roles in assembling this unique molecule. This paper reports the crystal structure of DynF, the gene product of one of the genes within the biosynthetic gene cluster of dynemicin. DynF is revealed to be a dimeric eight‐stranded β‐barrel structure with palmitic acid bound within a cavity. The presence of palmitic acid suggests that DynF may be involved in binding the precursor polyene heptaene, which is central to the synthesis of the ten‐membered ring of the enediyne core. [ABSTRACT FROM AUTHOR]

Background and Purpose: Specific cellular functions mediated by GPCRs are often associated with signalling through a particular G protein or β‐arrestin. Here, we examine signalling through a GPCR, protease‐activated receptor 2 (PAR2), in a high‐grade serous ovarian cancer cell line (OV90). Experimental Approach Human ovarian cancer tissues (n = 1,200) and nine human ovarian cancer cell lines were assessed for PAR2 expression. PAR2 signalling mechanisms leading to cell migration and invasion were dissected using cellular assays, western blots, CRISPR‐Cas9 gene knockouts, pharmacological inhibitors of PAR2 and downstream signalling proteins in OV90 cancer cells. Key Results: PAR2 was significantly overexpressed in clinical ovarian cancer tissues and in OV90 ovarian cancer cells. PAR2 agonists, an endogenous protease (trypsin) and a synthetic peptide (2f‐LIGRL‐NH2), induced migration and invasion of OV90 ovarian cancer cells through activating a combination of Gαq/11, Gα12/13 and β‐arrestin1/2, but not Gαs or Gαi. This novel cooperative rather than parallel signalling resulted in downstream serial activation of Src kinases, then transactivation of epidermal growth factor receptor (EGFR), followed by downstream MEK–ERK1/2–FOS/MYC/STAT3–COX2 signalling. Either a PAR2 antagonist (I‐191), CRISPR‐Cas9 gene knockouts (PAR2 or Gα proteins or β‐arrestin1/2), or inhibitors of each downstream protein attenuated human ovarian cancer cell motility. Conclusion and Implications: This study highlights a novel shared signalling cascade, requiring each of Gαq/11, Gα12/13 and β‐arrestin1/2 for PAR2‐induced ovarian cancer cell migration and invasion. This mechanism controlling a cellular function is unusual in not being linked to a specific individual G protein or β‐arrestin‐mediated signalling pathway. [ABSTRACT FROM AUTHOR]