DDX5 inhibits inflammation by modulating m6A levels of TLR2/4 transcripts during bacterial infection.

DExD/H-box helicases are crucial regulators of RNA metabolism and antiviral innate immune responses; however, their role in bacteria-induced inflammation remains unclear. Here, we report that DDX5 interacts with METTL3 and METTL14 to form an m6A writing complex, which adds N6-methyladenosine to transcripts of toll-like receptor (TLR) 2 and TLR4, promoting their decay via YTHDF2-mediated RNA degradation, resulting in reduced expression of TLR2/4. Upon bacterial infection, DDX5 is recruited to Hrd1 at the endoplasmic reticulum in an MyD88-dependent manner and is degraded by the ubiquitin-proteasome pathway. This process disrupts the DDX5 m6A writing complex and halts m6A modification as well as degradation of TLR2/4 mRNAs, thereby promoting the expression of TLR2 and TLR4 and downstream NF-κB activation. The role of DDX5 in regulating inflammation is also validated in vivo, as DDX5- and METTL3-KO mice exhibit enhanced expression of inflammatory cytokines. Our findings show that DDX5 acts as a molecular switch to regulate inflammation during bacterial infection and shed light on mechanisms of quiescent inflammation during homeostasis.

Biorthogonal Dynamical Quantum Phase Transitions in Non-Hermitian Systems.

By utilizing biorthogonal bases, we develop a comprehensive framework for studying biorthogonal dynamical quantum phase transitions in non-Hermitian systems. With the help of the previously overlooked associated state, we define the automatically normalized biorthogonal Loschmidt echo. This approach is capable of handling arbitrary non-Hermitian systems with complex eigenvalues and naturally eliminates the negative value of Loschmidt rate obtained without the biorthogonal bases. Taking the non-Hermitian Su-Schrieffer-Heeger model as a concrete example, a 1/2 change of dynamical topological order parameter in biorthogonal bases is observed which is not shown in self-normal bases. Furthermore, we discover that the periodicity of biorthogonal dynamical quantum phase transitions depends on whether the two-level subsystem at the critical momentum oscillates or reaches a steady state.

Understanding the Quantum Rabi Ring Using Analogies to Quantum Magnetism.

We map a quantum Rabi ring, consisting of N cavities arranged in a ring geometry, into an effective magnetic model containing the XY exchange and the Dzyaloshinskii-Moriya (DM) interactions. The analog of the latter is induced by an artificial magnetic field, which modulates photon hopping between nearest-neighbor cavities with a phase. This mapping facilitates the description and understanding of the different phases in the quantum optical model through simple arguments of competing magnetic interactions. For the square geometry (N=4) the rich phase diagram exhibits three superradiant phases denoted as ferro-superradiant, antiferro-superradiant, and chiral superradiant. In particular, the DM interaction is responsible for the chiral phase in which the energetically degenerate configurations of the order parameters are similar to the in-plane magnetizations of skyrmions with different helicities. The antiferro-superradiant phase is suppressed in the triangle geometry (N=3) as geometric frustration contributes to stabilize the chiral phase even for small values of the DM interaction. The chiral phases for odd and even N show a different scaling behavior close to the phase transition. The equivalent behavior on both systems opens the possibility of simulating chiral magnetism in a few-body quantum optical platform, as well as understanding one system using the insights gained from the other.

Quantum Phases in a Quantum Rabi Triangle.

The interplay of interactions, symmetries, and gauge fields usually leads to intriguing quantum many-body phases. To explore the nature of emerging phases, we study a quantum Rabi triangle system as an elementary building block for synthesizing an artificial magnetic field. We develop an analytical approach to study the rich phase diagram and the associated quantum criticality. Of particular interest is the emergence of a chiral-coherent phase, which breaks both the Z_{2} and the chiral symmetry. In this chiral phase, photons flow unidirectionally and the chirality can be tuned by the artificial gauge field, exhibiting a signature of broken time-reversal symmetry. The finite-frequency scaling analysis further confirms the associated phase transition to be in the universality class of the Dicke model. This model can simulate a broad range of physical phenomena of light-matter coupling systems, and may have an application in future developments of various quantum information technologies.

Kinetics of 5-hydroxymethylfurfural formation in the sugar-amino acid model of Maillard reaction.

BACKGROUND: As a potential health hazard, 5-hydroxymethylfurfural (HMF) has been detected in thermally processed foods high in sugar and amino acids. In order to analyze HMF quantitatively and investigate the kinetics of its formation, high-performance liquid chromatography was employed to determine the content of HMF in six sugar-amino acid thermal reaction models. RESULTS: In thermal reaction models, formation of HMF was significantly affected by sugar and amino acid composition, pH value and heating conditions. HMF formation increased with increasing sugar and amino acid (cysteine excepted) content, temperature and reaction time. A maximum amount of HMF of 1.50 g kg-1 was detected in the sucrose-glutamic acid model at 110 °C and 6 h. Low pH value and added acidic amino acids promoted the formation of HMF, especially in the sucrose-containing system. CONCLUSION: HMF formation followed first-order kinetics in four models, including the model of glucose-cysteine, glucose-glutamic acid, glucose-leucine and sucrose-leucine. In contrast, HMF formation followed zero-order kinetics in the model of sucrose-glutamic acid. The quantity of HMF increased as the quantity of sugar and amino acid increased (cysteine excepted) in six tested models. © 2018 Society of Chemical Industry.

[Studies on difference of chemical compositions in plant species of Tripterygium genus].

We studied the content of chemical compositions and correlation among species of Tripterygium genus by principal component analysis(PCA) and variance analysis(ANOVA), and we also studied the difference among the 3 species.Using [BMIm]PF6 ionic liquid-based ultrasonic-assisted extraction, we determined the contents of 11 compounds including wilforgine, wilforzine, triptophenolide, wilforine, triptoquinone A, triptolide, tripterin, egallocatechin, epigallocatechin, catechin, and epicatechin in 28 batches of the Tripterygium species by HPLC and PCA. Partial least squares analysis (PLS) and ANOVA were also performed to verify the results.The analysis results of PCA and PLS showed that three species of Tripterygium genus were clustered into three regions respectively, and triptoquinone A was the important factor which affected the aggregation of these three species.There was a significant difference among the contents of 11 chemical components in the three species(P<0.000 1).These results indicated that there was a certain correlation between the chemical compositions and the classification of the species, and the difference of the chemical compositions among the three species was obvious. In this work, the content determination method is rapid and accurate, and the analysis method is simple and convenient, which provides a reference for the classification, the efficacy and the toxicity of the species.

Cantharimide and Its Derivatives from the Blister Beetle Mylabris phalerata Palla.

Eleven new monoterpenoids including three 1-methyl cantharimide-type derivatives (1-3), five 1,2-dimethyl cantharimide-type derivatives (4, 5, 7-9), and three 1-hydroxymethyl-2-methyl cantharimide-type derivatives (10-12), together with seven known cantharimides (6, 13-18), were isolated from Mylabis phalerata Palla. The planar structures and absolute configurations of compounds 1-14 were fully elucidated on the basis of spectroscopic analysis, ECD spectra, single-crystal X-ray diffraction analysis, and chemical methods. Compounds 6, 15, 16, and 18 were found to be potent inhibitors of HBV virus, with IC50 values of 62, 42, 58, and 19 µM.

[Chemical constituents from Mylabris phalerata and their cytotoxic activity in vitro].

Ten compounds were isolated from Mylabris phalerata by using preparative HPLC and column chromatography over MCI gel. On the basis of physical-chemical properties, NMR and MS data analysis, the compounds were identified as 5'-[(1 R,2 R,3 S,6R)-1-hydroxymethyl-2-methyl-3,6-epoxycyclohexane-1,2-dicarboximide]- ethyl-2'-methyl-2'-butenoate (1),cantharidin (2), cyclo-(L-Pro-L-Ala) (3), cyclo-(R-Pro-R-Leu) (4), cyclo-(S-Pro-R-Leu) (5), cyclo-(D-Pro-L-Tyr) (6), indole-3-aldehyde (7), 3-indoleacetic acid (8), valerolactam (9), and 4-hydroxyphthalid (10).Compound 1 was a new compound, and compounds 2-10 were obtained from this genus for the first time. Compounds 1-9 were subjected to cytotoxic activity on HCT-116, HepG2, BGC-823, NCI-H1650, A2780 cell lines, and only compound 2 showed inhibitory effect on all cancer cell lines.

Distinguishing the strength of electronic coupling for Mo2 -containing mixed-valence compounds within the Class III regime.

Two, symmetrical, mixed-valence (MV), complex cations-{[Mo2 (DAniF)3 ]2 (µ-oxamidate)}(+) (1(+) ) and {Mo2 (DAniF)3 ]2 (µ-dithiooxamidate)}(+) (2(+) ; DAniF=N,N'-di(p-anisyl)formamidinate)-are significantly differentiated in terms of electronic coupling between the two [Mo2 ] units. For 1(+) the intervalence (IV) charge-transfer band in the near-IR spectrum is truncated in half on the low-energy side as predicted for MV compounds at the Class II-III limit (2Hab /λ=1; for which Hab =electronic coupling matrix element and λ=reorganization energy). In contrast, the very strongly coupled analogue 2(+) , as indicated by 2Hab /λ=3.5 (> >1), exhibits a higher energy and more symmetrical IV band. As rare examples, this pair of MV species shows distinct optical behaviors for MV systems crossing the Class III region. Optical analysis and DFT calculations are carried out to elucidate the transformation from vibronic to electronic vertical transition.

Clinical and molecular characteristics of emerging hypervirulent Klebsiella pneumoniae bloodstream infections in mainland China.

Recently, the newly emerged hypervirulent Klebsiella pneumoniae strain (hvKP) has caused great concern globally, but the clinical features and molecular characteristics of bacteremia caused by hvKP are rarely reported in mainland China. Seventy patients with K. pneumoniae bacteremia were investigated to study the clinical features of hvKP infection from 2008 till 2012 in Beijing Chao-Yang Hospital. The molecular characteristics of the hvKP strains were also studied using PCR, multilocus sequence typing, and pulsed-field gel electrophoresis (PFGE) methods. hvKP was identified in 31.4% of the patients with K. pneumoniae bacteremia, which displayed 4 serotypes (K1, K2, K20, and K57). Patients with hvKP infection tended to have no underlying diseases compared to those with classic K. pneumoniae (cKP). More hvKP-positive patients (95.5%) had community-acquired infection than did cKP-infected patients (35.4%) (P<0.001). The 30-day mortality rate was lower in hvKP-infected patients than in cKP-infected patients (4.5% compared to 16.7%). Resistance to tested antimicrobials was significantly greater in cKP- than in hvKP-infected patients. Two extended-spectrum-beta-lactamase (ESBL)-producing hvKP strains were found. Seven novel sequence types (STs) and 4 new alleles of K. pneumoniae were revealed. A strong correlation was found between two STs (ST23, ST1265) and the K1 serotype. The hvKP isolates (n=22) had 14 different PFGE patterns, and among them 10 K1 isolates shared similar PFGE patterns. The emerging hvKP strain was prevalent in patients with severe community-acquired infections in healthy individuals in China. Identification of ESBL-producing hvKP strains in hvKP-infected patients will facilitate clinical management of hvKP infection.

Covalent Organic Framework-Based Theranostic Platforms for Restricting H1N1 Influenza Virus Infection.

Background: Influenza A (H1N1) virus is a highly contagious respiratory disease that causes severe illness and death. Vaccines and antiviral drugs are limited by viral variation and drug resistance, so developing efficient integrated theranostic options appears significant in anti-influenza virus infection. Methods: In this study, we designed and fabricated covalent organic framework (COF) based theranostic platforms (T705@DATA-COF-Pro), which was composed of an RNA polymerase inhibitor (favipiravir, T705), the carboxyl-enriched COF (DATA-COF) nano-carrier and Cy3-labeled single DNA (ssDNA) probe. Results: The multi-porosity COF core provided an excellent micro-environment and smooth delivery for T705. The ssDNA probe coating bound to the nucleic acids of H1N1 selectively, thus controlling drug release and allowing fluorescence imaging. The combination of COF and probe triggered the synergism, promoting drug further therapeutic outcomes. With the aid of T705@DATA-COF-Pro platforms, the H1N1-infected mouse models lightly achieved diagnosis and significantly prolonged survival. Conclusion: This research underscores the distinctive benefits and immense potential of COF materials in nano-preparations for virus infection, offering novel avenues for the detection and treatment of H1N1 virus infection.

Legacy and alternative flame retardants in typical freshwater cultured fish ponds of South China: Implications for evolving industry and pollution control.

The production and usage of polybrominated diphenyl ethers (PBDEs) has been gradually phased out and the application of alternative halogenated flame retardants (AHFRs) has been continuously increased. It is essential to understand how the evolving flame retardants industry has affected the occurrence and flux of legacy and alternative flame retardants so that better pollution control measures can be made accordingly. Air, rainwater, inflowing river water, pond water, pond sediment, fish feed, and fish collected from freshwater cultured fish ponds (FWCFPs) within the Pearl River Delta, South China were analyzed for PBDEs and AHFRs. Concentrations of AHFRs in air (range; median: 7.8-870; 210 pg m-3), rainwater (0.88-65; 4.8 ng L-1), and sediment (19-120; 54 ng g-1 dry weight (d.w.)) were one order of magnitude higher than those of PBDEs in air (12-98; 21 pg m-3), rainwater (0.18-15; 0.70 ng L-1), and sediment (1.5-9.6, 2.9 ng g-1 d.w.) (t-test; p < 0.05). Decabromodiphenyl ether and decabromodiphenylethane were the predominant BDE and AHFR components, respectively, agreeing well with the production and usage patterns of flame retardants in China. The average input fluxes of AHFRs to the FWCFPs via dry deposition, wet deposition, net air-water exchange, and feeding (38.6, 20.6, and 2.14, µg m-2 yr-1) were one order of magnitude higher than those of PBDEs (3.44, 5.17, and -10.1, µg m-2 yr-1). Elevated occurrence and input fluxes of AHFRs suggested that aquaculture production is potentially facing a new challenge from alternative flame retardants. Atmospheric dry and wet deposition are important input sources of AHFRs to the FWCFPs. Feeding is an important input pathway for both PBDEs and AHFRs. Pollution control measures should be modified to accommodate the evolving flame retardants industry.

[Effects of leaf extracts of Amorpha fruticosa on seed germination and seedling growth of Amygdalus pedunculata]. / 紫穗槐叶片浸提液对长柄扁桃种子萌发和幼苗生长的影响.

Amorpha fruticosa and Amygdalus pedunculata are common plant species used for greening construction in arid and semi-arid region of Northwest China. In order to explore the feasibility of greening construction and ecological restoration by A. fruticose with A. pedunculata, we exami-ned the allelopathic effects of five concentrations of aqueous leaf extracts of A. fruticosa (0.025, 0.05, 0.10, 0.15 and 0.20 g·mL-1) on eight A. pedunculata varieties (YY1, YY3, YY4, YY5, YY6, SM6, SM7 and SM8), using the methods of paper-petri dish and soilless culture. The results showed that when the concentration of A. fruticosa leaf extracts were 0.025 and 0.05 g·mL-1, the seed germination and seedling growth of YY1 and SM6 were significantly better than other varieties. With increasing concentration of A. fruticosa leaf extracts, the catalase activity of A. pedunculata seedlings first increased and then decreased. The activities of peroxidase and superoxide dismutase, and the contents of soluble protein and chlorophyll showed a downward trend, while the contents of malondialdehyde and soluble sugar and the permeability of cell membrane gradually increased. Results of the principal component and cluster analysis showed that the growth potential of A. pedunculata decreased with the order of YY1, SM6, SM8, SM7, YY6, YY3, YY5 and YY4 under the allelopathic effect of A. fruticose. In conclusion, the artificial collocation and mixed planting of low-density of A. fruticosa with YY1 and SM6 were beneficial to seed germination and seedling growth of A. pedunculata.

High prevalence of macrolide resistance in Mycoplasma pneumoniae isolates from adult and adolescent patients with respiratory tract infection in China.

The resistance rate of 67 Mycoplasma pneumoniae isolates from 356 ambulatory adult patients with respiratory tract infection was 69% (46 of 67). All 46 macrolide-resistant strains harbored point mutations in the 23S ribosomal RNA gene. Patients infected with macrolide-resistant M. pneumoniae required significantly longer durations of antibiotic therapy and had longer time to resolution of fever.

Selected antibiotics and current-use pesticides in riverine runoff of an urbanized river system in association with anthropogenic stresses.

Antibiotics and current-use pesticides are ubiquitous in the environment. It is important to figure out their spatial distribution under the influences of anthropogenic activities and transport from rivers to coastal oceans. To address this knowledge gap, the present study conducted quarterly sampling in eight main runoff outlets of the Pearl River, South China, and obtained total concentrations of antibiotics and current-use pesticides at 24-296 ng L-1. Higher total concentrations of these chemicals occurred in summer, attributed to seasonal consumption patterns and washout by rainfalls, respectively. The spatial distributions of target analytes were not significantly different between the eastern and western outlets with high and moderate urbanization levels, respectively. Approximately 16.4, 17.7, and 12.5 tons of antibiotics, organophosphorus pesticides, and neonicotinoids were discharged annually from the outlets to the South China Sea. These results suggested that usage amount and hydrology exhibited positive effects on the riverine inputs of the target chemicals. In addition, most target chemicals exhibited low risks to green algae, but erythromycin and parathion posed high ecological risks to aquatic organism (Daphnid and fish).

Comparative study of c-Fos expression in rat dorsal vagal complex and nucleus ambiguus induced by different durations of restraint water-immersion stress.

Restraint water-immersion stress (RWIS) of rats induces vagally-mediated gastric dysfunction. The present work explored the effects of different durations of RWIS on neuronal activities of the dorsal vagal complex (DVC) and the nucleus ambiguous (NA) in rats. Male Wistar rats were exposed to RWIS for 0, 30, 60, 120, or 180 min. Then, a c-Fos immunoperoxidase technique was utilized to assess neuronal activation. Resumptively, c-Fos expression in DVC and NA peaked at 60 min of stress, subsequently decreased gradually with increasing durations of RWIS. Interestingly, the most intense c-Fos expression was observed in the dorsal motor nucleus of the vagus (DMV) during the stress, followed by NA, nucleus of solitary tract (NTS) and area postrema (AP). The peak of c-Fos expression in caudal DMV appeared at 120 min of the stress, slower than that in rostral and intermediate DMV. The c-Fos expression in intermediate and caudal NTS was significantly more intense than that in rostral NTS. These results indicate that the neuronal hyperactivity of DMV, NA, NTS and AP, the primary center that control gastric functions, especially DMV and NA, may play an important role in the disorders of gastric motility and secretion induced by RWIS.

Powerful harmonic charging in a quantum battery.

We consider a harmonic charging field as an energy charger for the quantum battery, which consists of an ensemble of two-level atoms. The charging of noninteracting atoms is completely fulfilled, which exhibits a substantial improvement over previous static charging fields. Involving the repulsive interactions of atoms, the fully charging is achieved with shorter charged period over the noninteracting case, yielding an advantage for the charging. Excluding the charging field, a quantum phase transition is induced by the attractive atom-atom interactions, and the interacting atoms become degenerate in the ground state. We find that the degenerate states play a negative role in the charging due to the gapless energies. The atoms with strong attractive interactions can not be charged completely, which is accompanied by a drop of the maximum stored energy.

Isolation and identification of the umami peptides from shiitake mushroom by consecutive chromatography and LC-Q-TOF-MS.

Umami is critical to the taste of shiitake mushroom. To isolate and identify umami peptides, fractions from hydrolyzed dried shiitake mushroom were separated by ultrafiltration, gel filtration chromatography (GFC), and reversed-phase high-performance liquid chromatography (RP-HPLC). Separations were combined with sensory evaluations (grading and taste dilution analysis) and analysis of electronic tongue, which were used to identify the most umami component in shiitake mushroom. Low-molecular-weight fractions (MW < 3 kDa) have the strongest flavor in the shiitake mushroom hydrolysate. In the 3 subfractions separated from low-molecular-weight fractions (MW < 3 kDa) by GFC, the second subfraction (F2) was selected for RP-HPLC analysis. The first peak (G1) in RP-HPLC was identified by LC-Q-TOF-MS, and 2 tripeptides and 3 dipeptides were identified. The amino acid sequence of these peptides were Gly-Cys-Gly, Glu-Pro-Glu, Cys-Met, Val-Phe, and Gly-Glu.

MicroRNA-9 enhanced radiosensitivity and its mechanism of DNA methylation in non-small cell lung cancer.

In order to improve the therapeutic effect of non-small cell lung cancer (NSCLC), it is critical to combine radiation and gene therapy. Our study found that the activation of microRNA-9 (miR-9) conferred ionizing radiation (IR) sensitivity in cancer cells. Furthermore, increased microRNA-9 promoter methylation level was observed after IR. Our study combined the IR and microRNA-9 overexpression treatment which leads to a significant enhancement in the therapeutic efficiency in lung cancer both in vitro and in vivo. Therefore, it is plausible that microRNA-9 can be used as a novel therapeutic strategy of NSCLC. MTT assay was performed to detect the effect of microRNA-9 on the survival and growth of NSCLC cells. Flow cytometry results showed that microRNA-9 enhanced the apoptosis of NSCLC cells. Wound healing assay found that microRNA-9 can inhibit the migration of NSCLC cells and enhance the effect of radiation on the migration of NSCLC cells. In addition, bisulfate sequencing PCR was performed to analyze the methylation status of the microRNA-9 promoter. In order to determine the effect of microRNA-9 and its promoter methylation status on proliferation and radio-sensitivity in vivo, a subcutaneous tumor formation assay in nude mice was performed. Results have shown that microRNA-9 overexpression increased the radiosensitivity of A549 cells by inhibiting cell activity and migration, and by increasing apoptosis. In addition, the promoter methylation status of the microRNA-9 gene increased in response to ionizing radiation. Our study demonstrated that microRNA-9 enhanced radiosensitivity in NSCLC and this effect is highly regulated by its promoter methylation status. These results will help to clarify regulatory mechanisms of radiation resistance thus stimulate new methods for improving radiotherapy for NSCLC.