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SUMMARY: Stomatal immunity plays an important role during bacterial pathogen invasion. Abscisic acid (ABA) induces plants to close their stomata and halt pathogen invasion, but many bacterial pathogens secrete phytotoxin coronatine (COR) to antagonize ABA signaling and reopen the stomata to promote infection at early stage of invasion. However, the underlining mechanism is not clear. SAD2 is an importin β family protein, and the sad2 mutant shows hypersensitivity to ABA. We discovered ABI1, which negatively regulated ABA signaling and reduced plant sensitivity to ABA, was accumulated in the plant nucleus after COR treatment. This event required SAD2 to import ABI1 to the plant nucleus. Abolition of SAD2 undermined ABI1 accumulation. Our study answers the long‐standing question of how bacterial COR antagonizes ABA signaling and reopens plant stomata during pathogen invasion. Significance Statement: Bacterial pathogens secret coronatine (COR) to recruit an importin β protein SAD2 for interfering ABA signaling in stomata and promote invasion. [ABSTRACT FROM AUTHOR]

The synergistic regulation of the multi‐functional sites on one receptor molecule with different cationic effectors for anion recognition is scarce to be well understood from the experiment and theory. In this work, a new anion receptor with three functional zones including ether hole, biurea and double bipyridine groups (EUPR) is designed expecting to enhance the chloride anion recognition together with a rational synthesis path being proposed based on four simple and mature organic reaction steps. The conformational structures of the designed receptor EUPR and the binding behaviors for three kinds of ions (Cl−, Na+, and Ag+) are deeply investigated by using density functional theoretical calculations. It is found that Cl− binding via the hydrogen bond interaction can be significantly enhanced and synergistically regulated by the two kinds of cations and the corresponding conformational changes of receptor EUPR. Especially, the conformational pre‐organization of receptor caused by the encapsulation of sodium ion into ether hole is benefit to the binding for Cl− in both thermodynamics and kinetics. Na+ binding, in turn, can ever be enhanced by chloride anion, whereas it seems that Ag+ binding cannot always be enhanced by chloride anion, reflecting an electrical complementary matching and mutual enhancement effect for different counter ions. Moreover, solvent effect calculations indicate that EUPR may be an ideal candidate structure for Cl− recognition by strategy of counter ion enhancement in water. Additionally, a visual study of intermolecular noncovalent interaction (NCI) and molecular electrostatic potential (ESP) are used for the analysis on the nature of interactions between receptor and bound ions. [ABSTRACT FROM AUTHOR]

By means of density functional theory calculations, the encapsulation capabilities of a series of azobenzen‐containing photoresponsive nanoring hosts (labeled as host 1, 2, 3, 4, 5 and 6 according to the number of the azo unit, respectively) for fullerene C60 were surveyed. Interestingly and abnormally, it is found that the host 5, of which the diameter is only 1.218 nm, can form stable full inclusion complex with C60. However, irrespective of their cavity sizes (11.98 ~ 12.94 Å) of the hosts, the structures 1 ~ 4 and 6 were all disable to form inclusion complex with C60. In this paper, the group‐number‐composition‐selective full inclusion host‐guest interaction of the azobenzene‐containing nanorings with fullerene C60 is firstly presented. The calculated interaction energies, together with the detection and visualization of the weak interaction regions, provided evidences for the host‐guest binding based on relative strong repulsion interaction in the full inclusion complex. Analysis on the frontier orbital feature of the host‐guest systems suggests that under the electron excited condition, the chemical activity may be transferred from host 5 to guest C60 by formation of the floating host‐guest complex, and the chemical reactivity of the host 5 can be passivated via formation of the full inclusion host‐guest complex. Additionally, UV–vis–NIR and 1H NMR spectra of the hosts before and after the formations of the complexes have been simulated and discussed qualitatively, which may be helpful for further experimental investigations in future. [ABSTRACT FROM AUTHOR]

Procyanidin B2 (PB2), a naturally occurring flavonoid abundant in a wide range of fruits, has been shown to exert antioxidant, anti‐inflammatory and anticancer properties. However, the role of PB2 in the prevention of cold stimulation (CS)‐induced liver injury. The present study was undertaken to determine the effects of PB2 on liver injury induced by cold stimulation and its potential molecular mechanisms. The present study results showed that treatment with PB2 significantly reduced CS‐induced liver injury by alleviating histopathological changes and serum levels of alanine transaminase and aspartate transaminase. Moreover, treatment with PB2 inhibited secretion of inflammatory cytokines and oxidative stress in cold‐stimulated mice. PB2 reduced cold stimulation‐induced inflammation by inhibiting TLR4/NF‐κB and Txnip/NLRP3 signalling. Treatment with PB2 reduced oxidative stress by activating Nrf‐2/Keap1, AMPK/GSK3β signalling pathways and autophagy. Furthermore, simultaneous application of Shh pathway inhibitor cyclopamine proved that PB2 targets the Hh pathway. More importantly, co‐treatment with PB2 and cyclopamine showed better efficacy than monotherapy. In conclusion, our findings provide new evidence that PB2 has protective potential against CS‐induced liver injury, which might be closely linked to the inhibition of Shh signalling pathway. [ABSTRACT FROM AUTHOR]

Heat capacities and enthalpies of formation of BaGd2O4 were determined by high‐temperature differential scanning calorimetry and high‐temperature oxide melt solution calorimetry, respectively. Thermodynamic stability of BaLn2O4 compounds increases with decreasing Ln3+ ionic radius. Previously reported data on BaNd2O4 and BaSm2O4 corroborate this trend. Missing data for compounds in BaO–Ln2O3 (Ln = La, Pr, Eu, Er) systems were estimated from established relations, thermodynamic assessment was performed, and binary phase diagrams were calculated. [ABSTRACT FROM AUTHOR]

Although the long non‐coding RNA THOR has been reported to promote cancer stem cell expansion in liver cancer and gastric cancer, its effects on osteosarcoma (OS) cells remain unclear. Here, we investigated the roles of THOR in the stemness and migration of OS cells. We report that the level of THOR is remarkably upregulated in OS cell spheroids compared to that in OS adherent cells. THOR overexpression increased spheroid formation ability and aldehyde dehydrogenase 1 (ALDH1) activity in OS adherent cells, and the opposite effect was observed in spheroids with THOR knockdown. Additionally, the spheroids formed by OS adherent cells exhibited a stronger migration ability, which was attenuated by THOR knockdown, and THOR overexpression increased OS cell migration. Mechanistically, mRNA stability, luciferase reporter, and RNA–RNA in vitro interaction assays indicated that THOR can directly bind to the middle region of the SOX9 3′‐untranslated region (UTR), and enhances its mRNA stability, thereby increasing its expression. Notably, SOX9 knockdown reduced the ability of THOR overexpression to promote the stemness of OS cells. These findings indicate that the lncRNA THOR can promote the stemness and migration of OS cells by directly binding to the middle region of SOX9 3′UTR, thereby enhancing SOX9 mRNA stability and increasing its expression; thus, we provide information that may be of use in identifying potential targets for OS treatment. A schematic model of the role of long non‐coding RNA THOR in maintaining neuroblastoma cell stemness. Mechanistically, THOR directly binds to the middle region of SOX9 3′UTR, which enhances SOX9 mRNA stability and thus increases its expression. [ABSTRACT FROM AUTHOR]

Summary: The sclerotium, a multicellular structure composed of the compact aggregation of vegetative hyphae, is critical for the long‐term survival and sexual reproduction of the plant‐pathogenic fungus Sclerotinia sclerotiorum. The development and carpogenic germination of sclerotia are regulated by integrating signals from both environmental and endogenous processes. Here, we report the regulatory functions of the S. sclerotiorum GATA‐type IVb zinc‐finger transcription factor SsNsd1 in these processes. SsNsd1 is orthologous to the Aspergillus nidulans NsdD (never in sexual development) and the Neurospora crassa SUB‐1 (submerged protoperithecia‐1) proteins. Ssnsd1 gene transcript accumulation remains relatively low, but variable, during vegetative mycelial growth and multicellular development. Ssnsd1 deletion mutants (Δnsd1‐KOs) produce phialides and phialospores (spermatia) excessively in vegetative hyphae and promiscuously within the interior medulla of sclerotia. In contrast, phialospore development occurs only on the sclerotium surface in the wild‐type. Loss of SsNsd1 function affects sclerotium structural integrity and disrupts ascogonia formation during conditioning for carpogenic germination. As a consequence, apothecium development is abolished. The Ssnsd1 deletion mutants are also defective in the transition from hyphae to compound appressorium formation, resulting in a loss of pathogenicity on unwounded hosts. In sum, our results demonstrate that SsNsd1 functions in a regulatory role similar to its ascomycete orthologues in regulating sexual and asexual development. Further, SsNsd1 appears to have evolved as a regulator of pre‐penetration infectious development required for the successful infection of its many hosts. [ABSTRACT FROM AUTHOR]

Sclerotinia sclerotiorum (Lib.) de Bary is a necrotrophic plant pathogen with a worldwide distribution. The sclerotia of S. sclerotiorum are pigmented multicellular structures formed from the aggregation of vegetative hyphae. These survival structures play a central role in the life and infection cycles of this pathogen. Here, we characterized an atypical forkhead (FKH)-box-containing protein, SsFKH1, involved in sclerotial development and virulence. To investigate the role of SsFkh1 in S. sclerotiorum, the partial sequence of SsFkh1 was cloned and RNA interference (RNAi)-based gene silencing was employed to alter the expression of SsFkh1. RNA-silenced mutants with significantly reduced SsFkh1 RNA levels exhibited slow hyphal growth and sclerotial developmental defects. In addition, the expression levels of a set of putative melanin biosynthesis-related laccase genes and a polyketide synthase-encoding gene were significantly down-regulated in silenced strains. Disease assays demonstrated that pathogenicity in RNAi-silenced strains was significantly compromised with the development of a smaller infection lesion on tomato leaves. Collectively, the results suggest that SsFkh1 is involved in hyphal growth, virulence and sclerotial formation in S. sclerotiorum. [ABSTRACT FROM AUTHOR]

The photophysical and photochemical properties of the sulfonyl azide‐based fluorescent probe DNS–Az and its reduction product DNS by hydrogen sulfide (H2S) have been investigated theoretically. The calculated results indicated the first excited states of DNS–Az was dark state (oscillator strength less than 0.03) and DNS was bright state (oscillator strength more than 0.1), which determined the predicted radiative rate kr of DNS–Az was much smaller than that of DNS, meanwhile, due to more larger reorganization energy of DNS–Az, its predicted internal conversion rate kic was four times larger than that of DNS; moreover, owing to the effect of heavy atom from sulfur atom in DNS–Az, its predicted intersystem crossing rate kisc was seven times larger than that of DNS, thus the calculated fluorescence quantum yield of DNS–Az was only 2.16% and that of DNS was more than 77.2%, the above factors is the basis for DNS–Az molecule to function as a fluorescent probe. Regarding both DNS‐Az and DNS molecules, their maximum Huang‐Rhys factors, which are less than unity, signify the reliability of 0–0 transitions between their S0 and S1 electronic states. In addition, for DNS, our simulated emission peak of the 0–0 transition is 515 nm, a value that exhibits enhanced accuracy and coherence when compared to the experimental datum of 528 nm. The reaction mechanism of DNS‐Az generating DNS by H2S has been investigated too, according to the potential energy profile, we found that the fluorescent probe firstly protonated, then this organic ion broke down into DNS with the aid of a proton. [ABSTRACT FROM AUTHOR]

Objective: Finite element (FE) method's correctness depends heavily on modeling method. This study aimed at determining whether the interfaces at bracket‐wire and between teeth can be simplified for multi‐teeth FE analysis. Method: A three‐dimensional FE model of a mandible was created from cone‐beam computed tomography scan. Due to symmetry, only a half of the mandible was modeled, which consisted of five teeth (first premolar extraction and only first molar), brackets and archwire, periodontal ligament (PDL), cortical bone, and cancellous bone. All the bone, teeth, and PDL were considered to be isotropic and linear. The En‐masse retraction case was simulated. A detailed model, which has contact elements between the bracket and archwire and between teeth, was developed to allow relative motion at the interfaces. A model with simplified interfacial conditions, which does not allow the relative motion, was also created. The stresses and displacements as results of the treatment on these two models were calculated and compared. Results: The stress and displacement distributions from the detailed model were more close to reality based on the expected displacement pattern of the clinical case than from the simplified model. The maximum stresses from the two methods were also different. The highest stress from the detailed model is twice as high as from the simplified model. Conclusions: The detailed model provides much more reasonable results than the simplified model. Thus, the simplified model should not be used to replace the detailed model if the stress magnitude and highest stress location are the expected outcomes. The effects of modeling the interfaces between elements that have relative motion in a finite element models have been evaluated and quantified. The main conclusions are as follows: Inadequate modeling of the interfaces of orthodontic bracket/wire and neighboring teeth results in unreasonable results in terms of initial tooth displacement and stresses.The simplified interface model should not be used if the magnitude and distribution of the stresses and displacement are of interest. [ABSTRACT FROM AUTHOR]

By means of density functional theory calculations, the encapsulation capabilities of a series of azobenzen‐containing photoresponsive nanoring hosts (labeled as host 1, 2, 3, 4, 5 and 6 according to the number of the azo unit, respectively) for fullerene C60 were surveyed. Interestingly and abnormally, it is found that the host 5, of which the diameter is only 1.218 nm, can form stable full inclusion complex with C60. However, irrespective of their cavity sizes (11.98 ~ 12.94 Å) of the hosts, the structures 1 ~ 4 and 6 were all disable to form inclusion complex with C60. In this paper, the group‐number‐composition‐selective full inclusion host‐guest interaction of the azobenzene‐containing nanorings with fullerene C60 is firstly presented. The calculated interaction energies, together with the detection and visualization of the weak interaction regions, provided evidences for the host‐guest binding based on relative strong repulsion interaction in the full inclusion complex. Analysis on the frontier orbital feature of the host‐guest systems suggests that under the electron excited condition, the chemical activity may be transferred from host 5 to guest C60 by formation of the floating host‐guest complex, and the chemical reactivity of the host 5 can be passivated via formation of the full inclusion host‐guest complex. Additionally, UV–vis–NIR and 1H NMR spectra of the hosts before and after the formations of the complexes have been simulated and discussed qualitatively, which may be helpful for further experimental investigations in future. [ABSTRACT FROM AUTHOR]