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Background Connective tissue growth factor (CTGF)-induced angiogenesis is a crucial factor in rheumatoid arthritis (RA), but CTGF-interacting protein and related molecular mechanism of their interaction have not been fully elucidated. Methods CTGF-interacting proteins were identified through the LC-MS/MS analysis of the Co-IP products from fibroblast-like synoviocyte (FLS) lysates, and the interaction between CTGF and annexin A2 (ANXA2) was further confirmed through Co-IP and BiFC assay. The binding domain, mutant, mechanism, and angiogenesis function were assessed by homology modeling, molecular docking, MTT, cell scratch, tube formation, and chick chorioallantoic membrane (CAM) assays. Additionally, severe combined immunodeficiency (SCID) mouse co-implantation model was constructed to confirm the effect of ANXA2/CTGF-TSP1 in the process of RA in vivo. Results ANXA2 was identified and verified as an interaction partner of CTGF for the first time by Co-IP and LC-MS/MS analysis. Co-localization of CTGF and ANXA2 was observed in RA-FLS, and direct interaction of the TSP-1 domain of CTGF and ANXA2 was determined in HEK293T cells. The spatial conformation and stable combination of the ANXA2/CTGF-TSP1 complex were assessed by homology modeling in the biomimetic environment. The function of the ANXA2/CTGF-TSP1 complex was proved on promoting FLS proliferation, migration, and angiogenesis in vitro and deteriorating FLS invasion and joint damage in SCID mice. Conclusions TSP-1 is the essential domain in CTGF/ANXA2 interaction and contributes to FLS migration and pannus formation, inducing the process of RA.

Linalool, as a fragrant monoterpene, is an important feedstock for food, pharmaceuticals, and cosmetics industries. Although our previous study had significantly increased linalool production by the directed evolution of linalool synthase and overexpression of the whole mevalonate pathway genes, the engineered yeast strain suffered from dramatically reduced biomass. Herein, a stress-free linalool-producing yeast cell factory was constructed by the combinational regulation of linalool synthase and farnesyl diphosphate synthase instead of multienzyme overexpression. First, the expression level of linalool synthase was successfully enhanced by introducing a N-terminal SKIK tag, which improved linalool production by 3.3-fold. Subsequently, the modular assembly of linalool synthase and dominant negative farnesyl diphosphate synthase via short peptide tags efficiently converted geranyl pyrophosphate to linalool. Additional downregulation of the native farnesyl diphosphate synthase led to the highest reported linalool production (80.9 mg/L) in yeast. This combinatorial modulation strategy may also be applied to the production of other high-value monoterpenes.

Layered transition metal dichalcogenides with excellent nonlinear absorption properties have shown remarkable performance in acting as ultrafast photonics devices. In our work, palladium diselenide (PdSe2) nanosheets with competitive advantages of wide tunable bandgap, unique puckered pentagonal structure and excellent air stability are prepared by the liquid-phase exfoliation method. Its ultrafast absorption performance was verified by demonstrating conventional and dissipative soliton operations within Er-doped fiber lasers. The minimum pulse width of the conventional soliton was 1.19 ps. Meanwhile, dissipative soliton with a 46.67 mW output power, 35.37 nm spectrum width, 14.92 ps pulse width and 2.86 nJ pulse energy was also generated successfully. Our enhanced experiment results present the excellent absorption performance of PdSe2 and highlight the capacity of PdSe2 in acting as ultrafast photonics devices.

Type I interferon (IFN) response is central for host defense against viral infection. Tripartite motif 27 (TRIM27) is implicated in antiviral innate immune response; however, whether it affects the replication of hepatitis C virus (HCV) and the underlying mechanisms remain uncharacterized. Here, we show that TRIM27 expression is induced in Huh7.5 human hepatoma cells infected with HCV or stimulated with type I IFNs in vitro. In addition, TRIM27 overexpression increases and its knockdown decreases viral RNA and protein levels, suggesting that TRIM27 positively regulates HCV replication. Mechanistically, TRIM27 inhibits type I IFN response against HCV infection through inhibiting IRF3 and NF-κB pathways, since TRIM27 mutant unable to inhibit these two inflammatory pathways fails to promote HCV replication. Taken together, this study identifies TRIM27 as a novel positive regulator of HCV replication, and also implicates that targeting TRIM27 may serve as a therapeutic strategy for controlling HCV replication.

Surgery is the main treatment for liver cancer in clinic owing to its low sensitivity to chemotherapy and radiotherapy, but this results in high mortality, recurrence, and metastasis rates. It is a feasible strategy to construct tumor microenvironments activated by nanotheranostics agents for the diagnosis and therapy of liver cancer. This study reports on a nanotheranostic agent (MONs@PDA-ICG) with manganese oxide nanoflowers (MONs) as core and polydopamine (PDA) as shell loading, with ICG as a photosensitizer and photothermal agent. MONs@PDA-ICG can not only produce ROS to kill cancer cells but also exhibit good photothermal performance for photothermal therapy (PTT). Importantly, O2 generated by MONs decomposition can relieve the tumor hypoxia and further enhance the treatment effects of photodynamic therapy (PDT). In addition, the released Mn2+ ions make MONs@PDA-ICG serve as tumor microenvironments responsive to MRI contrast for highly sensitive and specific liver cancer diagnosis.

For the unicellular alga Chlamydomonas reinhardtii, the presence of N-glycosylated proteins on the surface of two flagella is crucial for both cell-cell interaction during mating and flagellar surface adhesion. However, it is not known whether only the presence or also the composition of N-glycans attached to respective proteins is important for these processes. To this end, we tested several C. reinhardtii insertional mutants and a CRISPR/Cas9 knockout mutant of xylosyltransferase 1A, all possessing altered N-glycan compositions. Taking advantage of atomic force microscopy and micropipette force measurements, our data revealed that reduction in N-glycan complexity impedes the adhesion force required for binding the flagella to surfaces. This results in impaired polystyrene bead binding and transport but not gliding of cells on solid surfaces. Notably, assembly, intraflagellar transport, and protein import into flagella are not affected by altered N-glycosylation. Thus, we conclude that proper N-glycosylation of flagellar proteins is crucial for adhering C. reinhardtii cells onto surfaces, indicating that N-glycans mediate surface adhesion via direct surface contact.

Background As a natural phenolic acid product of plant source, caffeic acid displays diverse biological activities and acts as an important precursor for the synthesis of other valuable compounds. Limitations in chemical synthesis or plant extraction of caffeic acid trigger interest in its microbial biosynthesis. Recently, Saccharomyces cerevisiae has been reported sporadically for biosynthesis of caffeic acid via free plasmid‑mediated pathway assembly. However, the production was far from satisfactory and even relied on the addition of precursor. Results In this study, we first established a controllable caffeic acid pathway by employing a modified GAL regulatory system in S. cerevisiae and realized de novo biosynthesis of 313.8 mg/L caffeic acid from glucose. Combinatorial engineering strategies including eliminating the tyrosine-induced feedback inhibition, deleting genes involved in competing pathways and overexpressing rate-limiting enzymes led to about 2.5-fold improvement in the caffeic acid production, reaching up to 769.3 mg/L in shake-flask cultures. To our knowledge, this is the highest ever reported titer of caffeic acid de novo synthesized by engineered yeast. Conclusions Caffeic acid production in S. cerevisiae strain was successfully improved by adopting a glucose-regulated GAL system and comprehensive metabolic engineering strategies. This work showed the prospect for microbial biosynthesis of caffeic acid and laid the foundation for constructing biosynthetic pathways of its derived metabolites.

For the unicellular algaChlamydomonas reinhardtii, the presence ofN-glycosylated proteins on the surface of two flagella is crucial for both cell-cell interaction during mating and flagellar surface adhesion. It is unknown whether the composition ofN-glycans attached to respective proteins is important for these processes. To this end, we examined severalC. reinhardtiiinsertional mutants and a CRIPSR/Cas9 knockout mutant of xylosyltransferase 1A, all possessing alteredN-glycan compositions. Taking advantage of atomic force microscopy and micropipette force measurements, our data revealed that reduction inN-glycan complexity impedes the adhesion force required for binding the flagella to surfaces. In addition, polystyrene bead binding and transport is impaired. Notably, assembly, Intraflagellar Transport and FMG-1B transport into flagella are not affected by alteredN-glycosylation. Thus, we conclude that properN-glycosylation of flagellar proteins is crucial for adheringC. reinhardtiicells onto surfaces, indicating thatN-glycans mediate surface adhesion via direct surface contact.

Surface-enhanced Raman scattering (SERS) is a promising analytical tool in nanoscale detection because of its high sensitivity and selectivity. This review focuses on recent advances in SERS-based detection of DNA and RNA. First, nanostructure-based SERS-active substrates are introduced. Using label-free and labeled SERS, target biomolecules such DNA, RNA and microRNA have been successfully detected. Finally, applications in pathogen diagnosis are discussed. The prospects and challenges of SERS-based bioanalysis are highlighted.

At present, only little is known about the enzymatic machinery required for N-glycosylation in Chlamydomonas reinhardtii, leading to the formation of N-glycans harboring Xyl and methylated Man. This machinery possesses new enzymatic features, as C. reinhardtii N-glycans are independent of β1,2-N-acetylglucosaminyltransferase I. Here we have performed comparative N-glycoproteomic analyses of insertional mutants of mannosidase 1A (IM Man1A ) and xylosyltransferase 1A (IM XylT1A ). The disruption of man1A affected methylation of Man and the addition of terminal Xyl. The absence of XylT1A led to shorter N-glycans compared to the wild type. The use of a IM Man1A xIM XylT1A double mutant revealed that the absence of Man1A suppressed the IM XylT1A phenotype, indicating that the increased N-glycan trimming is regulated by core β1,2-Xyl and is dependent on Man1A activity. These data point toward an enzymatic cascade in the N-glycosylation pathway of C. reinhardtii with interlinked roles of Man1A and XylT1A. The results described herein represent the first step toward a functional characterization of the enzymatic N-glycosylation machinery in C. reinhardtii.

Hepatitis B is a widespread and potentially life-threatening disease caused by the hepatitis B virus, tyrosine-methionine-aspartate-aspartate (YMDD) - motif mutant is a known HBV variant and responsible for the drug resistance during Long-term lamivudine treatment. In this work, spermine-coated silver nanoparticles were used as surface-enhanced Raman scattering enhancement matrices to detect mutations in single sites of the hepatitis B virus single-stranded DNA. The unique Raman finger-print spectrum of DNA based on spermine-coated silver nanoparticles was detected. And the signals from the phosphate backbone allowed to be an internal standard for standardize the surface-enhanced Raman spectrum of DNA oligonucleotides. The spectral changes were quantitatively related to the composition of adenine in the DNA strand, and the correlation performance reached 0.99. The relative standard deviation of surface-enhanced Raman spectroscopy signal corresponding to the tyrosine-isoleucine-aspartate-aspartate (YIDD), tyrosine-valine-aspartate-aspartate (YVDD), and YMDD was 5.43 %, 7.5 %, and 7.28 %, respectively. The proposed method provides a potential tool for YMDD-motif mutants detection and reference for therapeutic drug monitoring.

With special fragrance and various biological properties, linalool has wide applications in food, pharmaceuticals and cosmetics industries. Microbial biosynthesis has become a promising approach to linalool production, however its efficiency is limited by the limited precursor supply and poor efficiency of linalool synthase. With the goal of enhancing heterologous linalool production in Saccharomyces cerevisiae, protein engineering and metabolic engineering were simultaneously employed to solve these bottlenecks. Linalool-producing yeast was first constructed by introduction of t67OMcLIS selected out from a collection of linalool synthases. The efficiency of linalool biosynthesis was then improved by strengthening the supply of geranyl pyrophosphate (GPP) as precursor via overexpression of the complete mevalonate (MVA) pathway and a GPP synthase variant. To accelerate the conversion of the accumulated GPP to linalool, t67OMcLIS was engineered by means of directed evolution after development of a competition-based color-indicated high-throughput screening method. Expression of the t67OMcLIS variant in the engineered S. cerevisiae with enhanced precursor supply yielded 53.14 mg/L of linalool in biphasic shake-flask culture. This study delivered an efficient linalool-producing yeast cell factory and meanwhile provided efficient strategies for biosynthesis of other valuable monoterpenes.

In this study, 3-ferrocenyl substituted cyclooctene (3FcCOE) monomer was synthesized and polymerized via the ring-opening metathesis polymerization (ROMP). The poly(3FcCOE) exhibited remarkably high head-to-tail regioregularity and high trans-stereoregularity. Diblock coplymer and triblock terpolymers were then synthesized by copolymerization of 3FcCOE with norbornene and N-methylnorbornene-5,6-dicarboximid. The monomers and polymers were characterized by 1H NMR and 13C NMR. The molecular weight and PDI of the polymers were determined by GPC. Moreover, electrochemical, DSC and tensile property tests of the various polymers were also show that they have unique physical properties.

The present study aimed to determine the in vitro activities of sulbactam and sitafloxacin against extensively-drug resistant Acinetobacter baumannii (XDR-A. baumannii). A total of 50 strains of XDR-A. baumannii were isolated from clinical specimens. Broth microdilution assay was applied to determine the minimum inhibitory concentration (MIC) for sulbactam and sitafloxacin. Microdilution checkerboard method was used to determine the in vitro activity of this antimicrobial combination. Accordingly, the fractional inhibitory concentration (FIC) and FIC index (FICI) were calculated. Time-kill study was also carried out for four strains with different susceptibilities to determine the bactericidal activities of individual or combined use of sitafloxacin and sulbactam. Isolates with MICs of sitafloxacin ≤2 mg/l were considered to be susceptible to sitafloxacin. The susceptibility rate for sitafloxacin was 92% originally. When combined with sulbactam, this rate increased to 96%. Microdilution checkerboard results indicated that, when tested in combination, sulbactam/sitafloxacin exhibited marked synergistic and partial synergistic effects on 16 and 50% of the 50 strains, respectively. Time-kill assay suggested that sulbactam enhanced the bactericidal activity of sitafloxacin and the combination induced a synergistic effect. For strains that were not susceptible to sitafloxacin, the bactericidal activities of the combination of sitafloxacin and sulbactam at a sub-MIC concentration were impaired. However, this impairment could be overcome with the increase of the concentration to 1X MIC. The present study demonstrated that sulbactam enhanced the in vitro antimicrobial activity of sitafloxacin against XDR-A. baumannii.

We investigated the combined effects of soil moisture and light intensity on the growth, development and ecophysiological characteristics of one-year old Amorpha fruticosa seedlings. Soil moisture and light intensity influenced the ecophysiological characteristics of Amorpha fruticosa seedlings. Soil moisture resulted in the decreases of growth rate, individual size, net photosynthetic rate, transpiration rate, leaf water loss rate (WLR), and biomass accumulation of plant parts, and led to increased leaf water saturation deficit (WSD). Under water stress, more photosynthetic products were allocated to root growth. With decreasing light intensity, net photosynthetic rate, transpiration rate, chla/b, water saturation deficit, water use efficiency, water loss rate and biomass accumulation declined, while Chla, Chlb, Chla+b and carotenoids (Car) increased and more photosynthetic products were allocated to stem and leaf growth. Maximum growth vigor, net photosynthetic rate and total biomass accumulation in Amorpha fruticosa seedlings was recorded at 75–80% soil water-holding capacity and 100% light density in greenhouse environments.

A high-efficiency Bi2Se3-based passively Q-switched Nd-doped fiber laser was demonstrated. The passively Q-switched operation produced a maximum average output power of 21.7 mW under a pulse repetition rate of 195.3 kHz, corresponding to a pulse energy of 111.2 nJ, which is much higher than the results obtained previously. Our results proved that CVD-Bi2Se3 is an excellent candidate for demonstrating large-energy pulse operations. In addition, this is the first demonstration focusing on the application of 2D materials for obtaining pulse fiber laser operation within a 1.3 µm region.

Different large-energy mode-locked operations were successfully obtained within a Bi2Se3-based Er-doped fiber laser. First, mode-locked operation with maximum pulse energy of 17.2 nJ and pulse width of 187 ns under a pulse repetition rate of 537.6 kHz was obtained under the pump power of 680 mW. In addition, the characteristics of dark solitons and soliton rains, which also exhibit large pulse energies, have been investigated experimentally. Our results fully proved that Bi2Se3 was an excellent candidate for investigating various mode-locked operations with large pulse energy due to its high nonlinear effect and high damage threshold.

Two-dimensional materials are now receiving continuously increasing attention due to their exceptional optical properties. Recently, it has been proved that indium selenide (InSe) is also an excellent photoelectric material, with wide applications in the field of photodetecters and so on. In our work, layered InSe was prepared through the liquid-phase exfoliation method, and the nonlinear saturable absorption properties of InSe were also experimentally investigated. In addition, InSe-polyvinyl alcohol film was successfully prepared and employed as an saturable absorber for demonstrating an Er-doped passive Q-switched mode-locked fiber laser for the first time. The largest Q-switched pulse energy was as high as 112.97 nJ and the narrowest mode-locked pulse duration was 2.96 ns at a repetition rate of 1.74 MHz. Our results fully indicate that InSe also has excellent nonlinear absorption properties in comparison with other commonly used 2D materials. Thus, the applications of InSe can be deeply investigated to promote the development of ultra-fast optics in the near future.

In this paper, tin selenide (SnSe2) is proposed as a saturable absorber (SA) for demonstrating a dual-wavelength passively Q-switched Yb-doped fiber laser. A film-type SnSe2-PVA SA was successfully prepared by incorporating the SnSe2 nanosheets with the polyvinyl alcohol. The nonlinear absorption properties of the SA were investigated within a Yb-doped fiber laser. Stable passively Q-switched pulse operation with a maximum output power of 18.03 mW under pump power of 680 mW was generated, and the minimum pulse duration was 966 ns under a pulse repetition rate of 168.7 kHz, corresponding to a pulse energy of 106.9 nJ. Thereinto, 18.03 mW, 168.7 kHz and 966 ns were all the recorded parameters obtained within a 2D material-based passively Q-switched ring-cavity Yb-doped fiber laser. The excellent results proved that SnSe2 has well-matched nonlinear absorption properties in comparison with other reported transition metal dichalcogenides, Thus, wide-ranging important potential applications of SnSe2 in the field of ultrafast optics will soon be recognized.

The corrosion inhibition behavior of benzotriazole, Na3PO4 and their mixture on carbon steel in 20 wt.% (0.628 mol l(-1)) tetra-n-butylammonium bromide aerated aqueous solution was investigated by weight-loss test, potentiodynamic polarization measurement, electrochemical impedance spectroscopy and scanning electron microscope/energy dispersive X-ray techniques. The inhibition action of BTA or SP or inhibitors mixture on the corrosion of carbon steel is mainly due to the inhibition of anodic process of corrosion. The results revealed that inhibitors mixtures have shown synergistic effects at lower concentration of inhibitors. At 2 g l(-1) BTA and 2 g l(-1) SP showed optimum enhanced inhibition compared with their individual effects.

A controlled porosity osmotic pump system with biphasic release of theophylline was developed for the nocturnal therapy of asthma. The developed system was composed of a tablet-in-tablet (TNT) core and a controlled porosity coating membrane. Release pattern of the developed system was influenced by amount of pore former (18.2-45.5%, w/w of polymer), weight gain (16-26 mg per tablet) of the coating membrane and osmotic agents used in inner layer of the TNT core. When sodium phosphate and sodium chloride were selected as the osmotic agents in inner and outer layer of the TNT core respectively, target release profile was obtained with coating solution cellulose acetate-polyethylene glycol 400-diethyl phthalate (54.5-36.4-9.1%, w/w) at a weight gain of 16-22 mg per tablet. To examine the mechanism of drug release, release profiles of osmotic agents, micro-environmental osmotic pressure and micro-environmental pH of the formulation during dissolution were studied. Micro-environmental osmotic pressure decreased and micro-environmental pH increased continuously during the whole dissolution process, theophylline release was dominated by the successive dissolution of sodium chloride and sodium phosphate. Theophylline solubility increased as environmental pH exceeded 10.8. At the last stage of the biphasic release, micro-environmental pH in the developed formulation reached 10.9, and theophylline release was promoted by its elevated solubility despite of the decrease of micro-environmental osmotic pressure in the developed formulaiton.

This study investigated the effects of berberine on amelioration of hyperglycemia and hyperlipidemia and the mechanism involved in high glucose and high fat diet-induced diabetic hamsters. Golden hamsters fed with high glucose and high fat diet were medicated with metformin, simvastatin, and low or high dose of berberine (50 and 100 mg·kg−1) for 6 weeks. The results showed that the body weights were significantly lower in berberine-treated groups than control group. Histological analyses revealed that the treatment of berberine inhibited hepatic fat accumulation. Berberine significantly reduced plasma total cholesterol, triglyceride, free fatty acid, low density lipoprotein cholesterol, malondialdehyde, thiobarbituric acid-reactive substance, and 8-isoprostane level but significantly increased plasma superoxide dismutase activity. Glucose and insulin levels were significantly reduced in metformin and berberine-treated groups. Glucose tolerance tests documented that berberine-treated mice were more glucose tolerant. Berberine treatment increased expression of skeletal muscle glucose transporter 4 mRNA and significantly decreased liver low density lipoprotein receptor mRNA expression. The study suggested that berberine was effective in lowering blood glucose and lipids levels, reducing the body weight, and alleviating the oxidative stress in diabetic hamsters, which might be beneficial in reducing the cardiovascular risk factors in diabetes.