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Compared with well-developed free space polarization converters, polarization conversion between TE and TM modes in the waveguide is generally considered to be caused by shape birefringence, like curvature, morphology of waveguide cross section and scattering. Here, we study the polarization conversion mechanism in 1-THz-FSR X-cut lithium niobate microrings with multiple-resonance condition, that is the conversion can be implemented by birefringence of waveguides, which will also introduce an avoided-mode crossing. In the experiment, we find that this mode crossing results in severe suppression of one sideband in local nondegenerate four-wave mixing and disrupts the cascaded four-wave mixing on this side. Simultaneously, we propose one two-dimensional method to simulate the eigenmodes (TE and TM) in X-cut microrings, and the mode crossing point. This work will provide one approach to the design of polarization converters and simulation for monolithic photonics integrated circuits, and may be helpful to the studies of missed temporal dissipative soliton formation in X-cut lithium niobate rings. [ABSTRACT FROM AUTHOR]

Studies into scatterings of photonic structures have been so far overwhelmingly focused on their dependencies on the spatial and spectral morphologies of the incident waves. In contrast, evolutions of scattering properties through another parameter space of incident directions (momentum space) has not attracted sufficient attention, with the underlying general governing rules still unrevealed. Here, from the perspective of quasi‐normal modes (QNMs), the momentum‐space scattering extremizations with respect to varying incident directions of plane waves are investigated. It is revealed that for effective single‐QNM excitations, scatterings are maximized exactly along those directions where the QNM radiation reaches its maximum, with matched incident and radiation polarizations. For an arbitrary direction, when the incident polarization is tuned to be orthogonal to that of the mode radiation, the QNM cannot be excited and thus the scatterer becomes invisible with null scatterings. The principles revealed are protected by fundamental laws of reciprocity and energy conservation (optical theorem), which can be further expanded and applied for other branches of wave physics. [ABSTRACT FROM AUTHOR]

In recent decades, the composition, structure, biosynthesis, and function of bacterial extracellular polysaccharides (EPS) have been extensively studied. EPS are synthesized through different biosynthetic pathways. The genes responsible for EPS synthesis are usually clustered on the genome or large plasmids of bacteria. Generally, different EPS synthesis gene clusters direct the synthesis of EPS with different chemical structures and biological activities. A better understanding of the gene functions involved in EPS biosynthesis is critical for the production of EPS with special biological activities. Genetic engineering methods are usually used to study EPS synthesis related genes. This review organizes the available information on EPS, including their structures, synthesis of related genes, and highlights the research progress of modifying EPS gene clusters through gene-editing methods. [ABSTRACT FROM AUTHOR]

Non-reciprocal phenomena generated by optical nonlinear effects without the requirement of external bias have important applications in modern photonics. In this paper, an optical nonlinear metasurface based on monolayer graphene integrated silicon resonant gratings is proposed. It is numerically confirmed that this type of metasurface can excite high-Q guided mode resonances in the communication band with normal incidence. Significant optical Kerr effect is achieved in the metasurface through high third-order polarization coefficient of graphene, and by changing the width and depth of the grating, the nonlinear effect of the metasurface can be effectively controlled to realize the application under different illumination conditions. In addition, remarkable non-reciprocity phenomenon is realized at an incident intensity of 0.085 G W / m 2. As an example, with a forward transmittance of 0.732 and a backward transmittance of 0.025, an optical diode is implemented at 1549.1 n m. Image 1 [ABSTRACT FROM AUTHOR]

Bacterial glucans have aroused increasing interest in commercial applications in the food and pharmaceutical sectors. A number of bacterial glucans have been reported over recent decades, and their structure, production, and functional properties have been extensively studied. In this paper, we review recent researches on bacterial glucans, with emphasis on the production, physical and chemical properties, and the new developments in food, biomedical, pharmaceutical, and other industrial applications. [ABSTRACT FROM AUTHOR]

The scattering of nanoparticles plays a profound role in the recently flourishing fields of plasmonics and metamaterials. However, current investigations into nanoparticle scattering are based on the electric and magnetic resonances only, where their toroidal counterparts are usually not considered. The inclusion of toroidal terms can render new explanations for some fundamental scattering properties and thus may stimulate further breakthroughs in both scattering-related basic researches and applications. Here we revisit the most fundamental problem of Mie scattering by individual spherical nanoparticles and show that compared to conventional interpretations in terms of electric and magnetic responses, the roles played by their toroidal counterparts are indispensable. Based on the demonstration of efficient toroidal dipole excitation in homogeneous dielectric particles, we reveal that the extensively studied scattering transparencies of core-shell nanoparticles can actually be classified into two categories: (i) the trivial transparency with no effective multipole excitations and (ii) the non-trivial transparency induced by the destructive interferences of excited electric and toroidal multipoles. The incorporation of toroidal multipoles offers new insights into the study of nanoparticle scattering in both near and far fields, which may shed new light on many applications, such as biosensing, imaging, nanoantennas, photovoltaic devices, and so on. [ABSTRACT FROM AUTHOR]

A picric acid-degrading bacterium, strain NJUST16, was isolated from a soil contaminated by picric acid and identified as a member of Rhodococcus sp. based on 16S rRNA sequence. The degradation assays suggested that the strain NJUST16 could utilize picric acid as the sole source of carbon, nitrogen and energy. The isolate grew optimally at 30°C and initial pH 7.0–7.5 in the mineral salts medium supplemented with picric acid. It was basically consistent with degradation of picric acid by the isolate. Addition of nitrogen sources such as yeast extract and peptone accelerated the degradation of picric acid. However, the stimulation was concentration dependent. The degradation was accompanied by release of stoichiometric amount of nitrite and acidification. The degradation of picric acid at relatively high concentrations (>3.93mM) demonstrated that the degradation was both pH and nitrite dependent. Neutral and slightly basic pH was crucial to achieve high concentrations of picric acid degradation by the NJUST16 strain. [Copyright &y& Elsevier]

To boost the power conversion efficiency of silicon/perovskite tandem solar cells, pyramid‐textured structures have been investigated and introduced into devices. However, high‐quality pyramid‐shaped single crystal preparation is an obstacle in tandem device development. Perovskite crystals obtained using general methods are cubic because of their structural symmetry and rapid growth rate. In this study, based on mass transfer boundary layer theory, a pyramid‐shaped perovskite single crystal is successfully obtained using an asymmetrically spatial confinement‐induced crystallization method. The synthesized pyramid crystals exhibited high crystallinity and enhanced optical absorption. A photodetector constructed using the as‐grown crystal exhibited high‐performance properties, including a responsivity of 9.4 A W−1, photo‐to‐dark current ratio of 2.3 × 104, and detectivity of 2.1 × 1011 Jones. Its unique insensitivity to the incident photon direction is also characterized. The flexible photodetector also exhibited excellent responsivity under different bending curvature radii. Additionally, the light‐trapping effect and absorption superiority of pyramid crystals over cuboid crystals are well established based on a semi‐empirical analytical model. This breakthrough in pyramid‐shaped perovskite crystal preparation provides a promising approach for the development of novel tandem solar cells and other optoelectronic devices. [ABSTRACT FROM AUTHOR]

Low-loss and high-reflection mirrors have important applications in high-power laser systems. Conventional mirrors based on multilayer films are damaged by thermal distortion between the layers when irradiated by high-power lasers. In 2022, H. Atikian et al. designed and demonstrated a dielectric metasurface mirror for high-power continuous-wave lasers with a bandwidth of 10 nm and a reflectance of 98.9 ± 0.3% by etching nanostructures into the surface of single-crystal diamond to overcome the limitation of coating defects. We optimize the structure to achieve a broadband high reflection of 100 nm with 99.88% average reflectance. Furthermore, we extend the structure to other typical optical materials to achieve high reflection, such as silicon, alumina, and silicon oxide and find that relatively high refractive index is important to realize broadband high reflection. Our work provides a reference for the design of homogeneous material-based metasurface mirrors operating under high power conditions. • Metasurface mirrors have important applications in high-power laser systems. • A diamond metasurface mirror with 99.88% reflectance of 100 nm bandwidth is realized. • Metasurface mirrors with Si, Al 2 O 3 , and SiO 2 are also studied. [ABSTRACT FROM AUTHOR]

Chalcogenide phase change materials enable the realization of novel, non-volatile, switchable electronic and photonic devices. In this paper, we propose a type of rewritable, non-volatile near infrared subwavelength absorber based on chalcogenide phase change materials. Our numerical simulations show that nearly perfect absorption more than 0.99 can be realized in the written state while the absorption of as-deposited or erased state is lower than 0.15 in the studied spectral range, leading to high contrast ratio of reflection more than 20 dB. Continuous tuning of the absorption spectra can be realized not only by varying the geometric parameters of the absorber but also by changing the crystallization ratio of the switched Ge 2 Sb 2 Te 5 (GST). The proposed device may find widespread applications in optical modulation, beam steering and so on. [ABSTRACT FROM AUTHOR]

Graphene has unique properties which make it an ideal material for photonic and optoelectronic devices. However, the low light absorption in monolayer graphene seriously limits its practical applications. In order to greatly enhance the light absorption of graphene, many graphene-based structures have been developed to achieve perfect absorption of incident waves. In this review, we discuss and analyze various types of graphene-based perfect absorption structures in the visible to terahertz band. In particular, we review recent advances and optoelectronic applications of such structures. Indeed, the graphene-based perfect absorption structures offer the promise of solving the key problem which limits the applications of graphene in practical optoelectronic devices. [ABSTRACT FROM AUTHOR]

Graphene plasmons are rapidly emerging as a versatile platform for manipulating light at the deep subwavelength scale. Here we show numerically that strong optical near-field forces can be generated under the illumination of mid-IR light when dielectric nanoparticles are located in the vicinity of a nanostructured graphene film. These near-field forces are attributed to the excitation of the graphene's plasmonic mode. The optical forces can generate an efficient optical trapping potential for a 10-nm-diameter dielectric particle when the light intensity is only about about 4.4 mW/μm2 and provide possibilities for a new type of plasmonic nano-tweezers. Graphene plasmonic tweezers can be potentially exploited for optical manipulation of nanometric biomolecules and particles. Moreover, the optical trapping/tweezing can be combined with biosensing and provide a versatile platform for studing biology and chemistry with mid-IR light. [ABSTRACT FROM AUTHOR]

Phase-contrast x-ray imaging using an x-ray interferometer has great potential to reveal the structures inside soft tissues, because the sensitivity of this method to hydrogen, carbon, nitrogen, and oxygen is about 1000 times higher than that of the absorption-contrast x-ray method. In this study, we used phase-contrast X-ray CT to investigate human resected esophagogastric junction. This technology revealed the three-layer structure of the esophagogastric junction wall-mucous, submucosa and muscular layers. The mucous and muscular layers were clearly separated by a loose submucosa layer with a honeycomb appearance. The shape of the mucous and muscular layers was intact. The boundary between the mucous and submucosa layers was distinct, as was the border of the muscular and submucosa layers. The surface of the esophagogastric junction was displayed clearly through 3D reconstruction. The technology might be helpful in the diagnosis of esophagogastric junction lesion, especially for the early adenocarcinoma. [ABSTRACT FROM AUTHOR]

Tunable and low-power microcavities are essential for large-scale photonic integrated circuits. Thermal tuning, a convenient and stable tuning method, has been widely adopted in optical neural networks and quantum information processing. Recently, graphene thermal tuning has been demonstrated to be a power-efficient technique, as it does not require thick spacers to prevent light absorption. In this paper, a silicon-based on-chip Fano resonator with graphene nanoheaters is proposed and fabricated. This novel Fano structure is achieved by introducing a scattering block, and it can be easily fabricated in large quantities. Experimental results demonstrate that the resonator has the characteristics of a high quality factor (∼31,000) and low state-switching power (∼1 mW). The temporal responses of the microcavity exhibit qualified modulation speed with 9.8 μs rise time and 16.6 μs fall time. The thermal imaging and Raman spectroscopy of graphene at different biases were also measured to intuitively show that the tuning is derived from the joule heating effect of graphene. This work provides an alternative for future large-scale tunable and low-power-consumption optical networks, and has potential applications in optical filters and switches. [ABSTRACT FROM AUTHOR]

Enhancing the lipid production of oleaginous yeasts is conducive to cutting the cost of feedstock for biodiesel. To increase the lipid productivity of Rhodotorula sp. U13N3, genes involving lipid degradation were knocked out and fermentation conditions were investigated. Results of transcription analysis demonstrated that genes encoding the ATG15-like lipase (ATG15) and peroxisomal acyl-CoA oxidase (ACOX2) were upregulated significantly at the lipogenesis stage. When ATG15 and ACOX2 were knocked out separately from the genome by the CRISPR/Cas9 method, both ΔATG15 and ΔACOX2 mutants showed better lipid production ability than the parent strain. Flow cytometry and confocal microscopic analyses indicated that simultaneous the knockout of ATG15 and ACOX2 did not impact the cell viability, whereas the lipid production was enhanced markedly as the lipid yield increased by 67.03% in shake flasks. Afterward, the ΔATG15ΔACOX2 transformant (TO2) was cultivated in shake flasks in the fed-batch mode; the highest biomass and lipid yield reached 45.76 g/L and 27.14 g/L at 216 h, respectively. Better performance was achieved when TO2 was cultivated in the 1-L bioreactor. At the end of fermentation (180 h), lipid content, yield, yield coefficient, and productivity reached 65.53%, 27.35 g/L, 0.277 g/g glycerol, and 0.152 g/L/h, respectively. These values were at the high level in comparison with Rhodotorula strains cultivated in glycerol media. Besides, fermentation modes did not affect the fatty acid composition of TO2 significantly. In conclusion, blocking the lipid degradation was an applicable strategy to increase the lipid production of Rhodotorula strains without compromising their cell viability. Key points: • ATG15-like lipase and acyl-CoA oxidase (ACOX2) participated in lipid degradation. • Knockout of ATG15 and ACOX2 increased lipid productivity, and lipid yield coefficient. • Cell viability maintained at high level in the knockout mutants during fermentation. [ABSTRACT FROM AUTHOR]

A kind of graphene-based perfect absorber which can generate low-threshold and high-extinction-ratio optical bistability in the near-IR band is proposed and simulated with numerical methods. The interaction between input light and monolayer graphene in the absorber can be greatly enhanced due to the perfect absorption. The large nonlinear coefficient of graphene and the strong light-graphene interaction contribute to the nonlinear response of the structure, leading to relatively low switching thresholds of less than 2.5 MW/cm2 for an absorber with a Q factor lower than 1000. Meanwhile, the extinction ratio of bistable states in the absorber reaches an ultrahigh value of 47.3 dB at 1545.3 nm. Moreover, the influence of changing the structural parameters on the bistable behaviors is discussed in detail, showing that the structure can tolerate structural parametric deviation to some extent. The proposed bistable structure with ultra-compact size, low thresholds, high extinction ratio, and ultrafast response time could be of great applications for fabricating high-performance all-optical-communication devices. [ABSTRACT FROM AUTHOR]

Many polysaccharides produced by Paenibacillus spp. have attractive properties, such as rheological modification and immunomodulation. However, properties of P. edaphicus polysaccharides are not understood sufficiently. Here, the polysaccharide (PUM) was obtained from P. edaphicus strain UJ1 by batch fermentation, and the chemical characteristics, rheological and anti-inflammatory properties of PUM and its sulfate derivative (PUM-S) were investigated. The results indicated that PUM was a typical shear-thinning biopolymer with an estimated weight average molecular weight of 2.45 × 107 Da. PUM molecule consisted of D-Man, D-GlcA, D-Glc, D-Gal, and L-Fuc with the molar ratio of 3.00:1.07:3.21:0.81:0.76. It had the backbone → 3)-β-D-Man-(1 → 3)-β-D-Glc-(1 → 3)-β-D-Man-(1 → 3)β-D-Glc-(1 → 4)-β-D-GlcA-(1 → 3)-β-D-Man-(1 → and two side chains, namely, pyruvoyl-Glc-(1→ and β-L-Fuc-(1 → 3)-β-D-Gal-(1→. Moreover, PUM-S was prepared by SO 3 -pyridine method and had the weight average molecular weight of 1.42 × 105 Da. The bioactivity of PUM and PUM-S was analyzed in vitro in RAW 264.7 cells. The results indicated that both PUM and PUM-S facilitated cell proliferation at 50–500 μg/mL. Besides, PUM-S showed potential anti-inflammatory effect in the LPS-induced cells. According to transcription and molecular dynamics analyses, PUM-S expressed its activity probably by interacting with the Toll-like receptor 4. In general, P. edaphicus produced a polysaccharide with new chemical structure and promising rheological and bioactive properties. • A polysaccharide PUM was obtained from Paenibacillus edaphicus strain UJ1. • PUM was a 2.45 × 107 Da macromolecular polysaccharide with good rheological properties. • Chemical characteristics of PUM and the sulfated PUM (PUM-S) was determined. • PUM and PUM-S facilitated proliferation of RAW 264.6 cells in vitro. • PUM-S showed potential anti-inflammatory activity by binding to TLR4. [ABSTRACT FROM AUTHOR]

Explorations of indefinite nanocavities have attracted surging interest in the past few years as such cavities enable light confinement to exceptionally small dimensions, relying on the hyperbolic dispersion of their consisting medium. Here, we propose and study indefinite graphene nanocavities, which support ultra-compressed mode volumes with confinement factors up to 10 9 . Moreover, the nanocavities we propose manifest anomalous scaling laws of resonances and can be effectively excited from the far field. The indefinite graphene cavities, based on low dimensional materials, present a novel rout to squeeze light down to the nanoscale, rendering a more versatile platform for investigations into ultra-strong light–matter interactions at mid-infrared to terahertz spectral ranges. [ABSTRACT FROM AUTHOR]

When light interacts with microscopic objects at the micro‐ and nano‐scale, the momentum exchange between photons and objects can be very significant. While the optical radiation pressure at the same level is usually too weak to change the mechanical state of macro‐scale objects at millimeter scale or beyond. Suspended metasurfaces with excellent mechanical and optical properties are ideal candidates for light‐matter interactions. Here, without sound insulation conditions, the spatial optical nonreciprocity based on an optomechanical system with a 2 mm × 2 mm × 110 nm Si3N4 suspended metasurface at the telecom wavelength is demonstrated, with peak wavelength shift up to 1.1 pm, which is about 4.0 times of the full width at half maximum, together with optical bistability at only about 10 W cm−2 input intensities, which is more than 4 orders of magnitude lower than traditional nonlinear optical mechanism. This work may pave new avenues for spatially nonreciprocal devices and bistable devices, and benefit the applications such as precision sensing, cavity quantum optomechanics, and all‐optical switching. [ABSTRACT FROM AUTHOR]

Lithium niobate is an excellent optoelectronic and nonlinear material, which plays an important role in integrated optics. However, lithium niobate is difficult to etch due to its very stable chemical nature, and the microstructure of lithium niobate's metasurface is generally of subwavelength, which further increases its processing difficulty. Here, by using Ar+-based inductively coupled plasma etching and KOH wet etching, we improve the etching quality and fabricate a Fano-resonant metasurface based on lithium niobate on insulator, which has a very high reflectivity of 92% at near-infrared wavelength and the potential of becoming a high-reflectivity film. In addition, to evaluate the practical performance of the metasurface, we constructed a Fabry–Perot cavity by using it as a cavity mirror, whose reflection spectrum shows a finesse of 38. Our work paves the way for the development of functional metasurfaces and other advanced photonic devices based on lithium niobate on insulator. [ABSTRACT FROM AUTHOR]

A very attractive advantage of graphene is that its Fermi level can be regulated by electrostatic bias doping. It is of great significance to investigate and control the spatial location of graphene emission for graphene thermal emitters, in addition to tuning the emission intensity and emission spectrum. Here, we present a detailed theoretical model to describe the graphene emission characteristics versus gate voltages. The experimentally observed movement of the emission spot and temperature distribution of graphene emitters are basically in agreement with those from the theoretical model. Our results provide a simple method to predict the behavior of graphene emitters that is beneficial for achieving the spatial dynamic regulation of graphene infrared emission arrays. [ABSTRACT FROM AUTHOR]

Riclinoctaose was produced by enzymatic hydrolysis of a succinoglycan‐type exopolysaccharide riclin. It can be used as a prebiotic to regulate the composition of gut microbiota. Therefore, a safety evaluation is needed. Here, we reported the safety data generated on riclinoctaose. Standard in vitro genotoxicity tests such as the bacterial reverse mutation assay and in vivo micronucleus assay were performed and no mutagenic or clastogenic potential was found. In the acute toxicity study, ICR mice were administered with riclinoctaose via gavage in 14‐day studies at the level corresponding to 3000 mg/kg BW/day. In the subchronic study, the diets containing 0%, 1.0%, 2.5%, and 5.0% of riclinoctaose (weight/weight) were prepared for ICR mice for 13 weeks. No test item‐related adverse effects were observed in the acute and subchronic studies. No riclinoctaose‐induced differences in the overall health, body weight gain, food and water consumption, hematology, blood chemistry, gross pathology, histopathology, or animal death were observed. A no‐observed‐adverse‐effect level of 8842 mg/kg BW/day for male and 9230 mg/kg BW/day for female mice was identified for riclinoctaose when administered for 13 weeks. In conclusion, these findings demonstrated the safety of riclinoctaose and indicated the possibility that riclinoctaose may be used as a functional food. Practical Application: Functional oligosaccharide is a low‐calorie sweetener, which is beneficial to human health. Dietary riclinoctaose can improve intestinal health and understanding the safety of riclinoctaose is the first step to evaluate its potential use in functional food. Therefore, genotoxicity, acute toxicity, and subchronic toxicity of riclinoctaose were studied. [ABSTRACT FROM AUTHOR]

• A spectrally selective radiation infrared stealth metafilm based on a simple bilayer structure is proposed and experimentally demonstrated. • The metafilm uses the common inexpensive metal Mo instead of traditional precious metals and can be easily fabricated. • The metafilm achieves infrared stealth with low emissivity in the atmospheric window and radiation heat dissipation with high emissivity in the non-atmospheric window. In this paper, we propose and demonstrate a spectrally selective radiation infrared stealth metafilm based on a simple bilayer structure. Specifically, we use the common inexpensive metal Mo instead of traditional precious metals and achieve selective thermal radiation in the infrared band. In the atmospheric window band, the absorptivity is relatively low, which can well achieve the purpose of infrared stealth, while in the non-atmospheric window band, the absorptivity acutely increases, with a high absorptivity of 94.89 % at 6.04 μ m , which can achieve better radiation heat dissipation. The experimental results are consistent with the simulation. The average emissivity in the 8–14 μ m atmospheric window band is 0.32, while in the 5–8 μ m non-atmospheric window band is 0.80, which proves the possibility of its practical application. Meanwhile, the metafilm proposed by us can be easily fabricated and can be widely used in the control of infrared thermal radiation, thermal management, and thermal camouflage, which has a very promising application prospect. [ABSTRACT FROM AUTHOR]

• Salecan mitigates LPS-induced ALI by preserving alveolar structure, reducing edema, and suppressing inflammation. • Salecan modulates oxidative stress pathways, reversing ALI-associated metabolic alterations. • Salecan may inhibit LPS-induced ALI through Keap1-Nrf2/HO-1 pathway. • Salecan interacts with macrophages, alleviating LPS-triggered apoptosis and inflammation. Acute lung injury (ALI) is a severe clinical condition with high mortality, characterized by rapid onset and limited treatment options. The pathogenesis of ALI involves inflammation and oxidative stress. The polysaccharide salecan, a water-soluble β-(1,3)-D-glucan, has been found to possess numerous pharmaceutical effects, including anti-inflammatory properties, inhibition of oxidative stress, and anti-fatigue effects. This study aims to investigate the protective effect and underlying mechanism of salecan against LPS-induced ALI in mice. Using an in vivo LPS-induced ALI mouse model and an in vitro RAW264.7 cell system, we investigated the role of salecan in ALI with various experimental approaches, including histological staining, quantitative real-time PCR, flow cytometry, western blot analysis, and other relevant assays. Pre-treatment with salecan effectively attenuated LPS-induced ALI in vivo, reducing the severity of pulmonary edema, inflammation, and oxidative stress. NMR-based metabolomic profiling analysis revealed that salecan attenuated LPS-induced metabolic imbalances associated with ALI. Furthermore, salecan downregulated Keap1 and upregulated Nrf2 and HO-1 protein levels, indicating its modulation of the Keap1-Nrf2/HO-1 signaling pathway as a potential mechanism underlying its protective effects against ALI. In vitro studies on RAW264.7 cells revealed that salecan exhibited binding affinity towards macrophages, thereby alleviating LPS-induced apoptosis and inflammation, which underpin its therapeutic potential against ALI. Our study suggests that salecan can alleviate LPS-induced ALI by modulating oxidative stress, inflammatory response, and apoptosis through the activation of the Keap1-Nrf2/HO-1 pathway. These findings provide novel insights into the potential therapeutic use of salecan for the treatment of ALI. [ABSTRACT FROM AUTHOR]

Effective management of excessive bleeding requires liquid hemostatic agents, especially in scenarios involving uncompressible and postoperative hemorrhage. This study introduces the microbial exopolysaccharide floccuronic acid (FA) as a liquid hemostatic agent, characterized by a high weight average molecular weight of 2.38 × 108 Da. The investigation focuses on the flocculation effect, hemostatic efficiency in both in vitro and in vivo settings, elucidating its hemostatic mechanism, and assessing its safety profile. Results reveal that FA solution significantly accelerates the coagulation process, leading to the formation of compact clots while specifically interfering with fibrin. Notably, FA demonstrates excellent hemostatic effects in animal liver models and a rat arterial rebleeding model. The biocompatible and biodegradable characteristics further underscore FA's potential as a valuable liquid hemostatic material, particularly suited for non-compressible and re-bleeding scenarios. [ABSTRACT FROM AUTHOR]

Requirement of clean energy sources urges us to find substitutes for fossil fuels. Microorganisms provide an option to produce feedstock for biofuel production by utilizing inexpensive, renewable biomass. Rhodotorula toruloides (Rhodosporidium toruloides), a non-conventional oleaginous yeast, can accumulate intracellular lipids (single cell oil, SCO) more than 70% of its cell dry weight. At present, the SCO-based biodiesel is not a price-competitive fuel to the petroleum diesel. Many efforts are made to cut the cost of SCO by strengthening the performance of genetically modified R. toruloides strains and by valorization of low-cost biomass, including crude glycerol, lignocellulosic hydrolysates, food and agro waste, wastewater, and volatile fatty acids. Besides, optimization of fermentation and SCO recovery processes are carefully studied as well. Recently, new R. toruloides strains are developed via metabolic engineering and synthetic biology methods to produce value-added chemicals, such as sesquiterpenes, fatty acid esters, fatty alcohols, carotenoids, and building block chemicals. This review summarizes recent advances in the main aspects of R. toruloides studies, namely, construction of strains with new traits, valorization of low-cost biomass, process detection and optimization, and product recovery. In general, R. toruloides is a promising microbial cell factory for production of biochemicals. [ABSTRACT FROM AUTHOR]

Current efforts in metamaterials research focus on attaining dynamic functionalities such as tunability, switching and modulation of electromagnetic waves. To this end, various approaches have emerged, including embedded varactors, phase-change media, the use of liquid crystals, electrical modulation with graphene and superconductors, and carrier injection or depletion in semiconductor substrates. However, tuning, switching and modulating metamaterial properties in the visible and near-infrared range remain major technological challenges: indeed, the existing microelectromechanical solutions used for the sub-terahertz and terahertz regimes cannot be shrunk by two to three orders of magnitude to enter the optical spectral range. Here, we develop a new type of metamaterial operating in the optical part of the spectrum that is three orders of magnitude faster than previously reported electrically reconfigurable metamaterials. The metamaterial is actuated by electrostatic forces arising from the application of only a few volts to its nanoscale building blocks-the plasmonic metamolecules-that are supported by pairs of parallel strings cut from a flexible silicon nitride membrane of nanoscale thickness. These strings, of picogram mass, can be driven synchronously to megahertz frequencies to electromechanically reconfigure the metamolecules and dramatically change the transmission and reflection spectra of the metamaterial. The metamaterial's colossal electro-optical response (on the order of 10−5-10−6 m V−1) allows for either fast continuous tuning of its optical properties (up to 8% optical signal modulation at up to megahertz rates) or high-contrast irreversible switching in a device only 100 nm thick, without the need for external polarizers and analysers. [ABSTRACT FROM AUTHOR]

Abstract: Disruption in circadian rhythms either by mutation in mice or by shiftwork in people, is associated with an increased risk for the development of multiple organ diseases. In turn, organ disease may influence the function of clock genes and peripheral circadian systems. Here we showed that hepatic fibrosis induced by carbon tetrachloride in mice leads to alterations in the circadian rhythms of hepatic clock genes. Especially, we found an impaired daily Cry2 rhythm in the fibrotic livers, with markedly decreased levels during the day time while compared with control livers. Associatively, the expressions of two important clock-regulated genes peroxisome proliferator-activated receptor alpha and cytochrome P450 oxidoreductase lost circadian rhythm with significantly decreased levels during the light–dark (12/12h) cycle in fibrotic livers. [Copyright &y& Elsevier]

Triphenyltin chloride (TPhT) is an organotin compound that causes intensive toxicological risk to the environment and humans. A detection method with high sensitivity and stability is therefore desired to better detect TPhT. In this study, a novel SERS substrate was prepared by sputtering an ultra-thin Au layer on a honeycomb-like silver nanoarray fabricated via the nanosphere lithography method. The ultra-thin Au layer was formed by sputtering the intermittent Au nanoparticles on the silver nanoarray, resulting in bimetallic coupling with dramatically increased hotspots and extremely high SERS enhancement with an analytical enhancement factor (AEF) of 6.08 × 109 using Rhodamine 6G (R6G) as the probe molecule. Based on density functional theory (DFT) simulations, the Raman characteristic peaks of TPhT at 999 cm−1 and 655 cm−1 were selected for TPhT detection. The AEF of the SERS substrate HC5-AgAu was calculated to be 3.38 × 106 with the detection concentration of TPhT down to 10−10 M. The as-prepared honeycomb-like silver–gold bimetallic SERS substrate demonstrated great stability and sensitivity for TPhT detection, which might also be applied in monitoring many other environmental pollutants. [ABSTRACT FROM AUTHOR]

Many studies have investigated the role of receptor-interacting protein 1 (RIP1) kinase in acetaminophen (APAP) overdose-induced acute liver injury. However, the results were not consistent and there still remain controversies. Importantly, in these previous studies, the usage of DMSO to dissolve the RIP1 kinase inhibitor Nec-1, resulted in misleading conclusion. Our study aimed to determine the role of RIP1 kinase in APAP-induced liver injury, via genetically or pharmaceutically inhibition of RIP1 kinase activity. Our results indicated that APAP-induced liver injury was significantly attenuated in RIP1 kinase-dead (Rip1 K45A/K45A ) mice compared to WT control. High dosage of APAP-induced mortality was also rescued by RIP1 kinase inactivation. In agreement, RIP1 kinase inhibitor, Nec-1 which was formulated with PEG400, could efficiently alleviate APAP-induced hepatotoxicity. For the underlying mechanism, our results suggested that RIP1 kinase inactivation did not influence the hepatic GSH depletion, but significantly reduced the hepatic cell death and inflammation induced by APAP treatment. Using bone marrow transplantation model, we also demonstrated that it was RIP1 kinase activity in tissue-resident hepatic cells other than hematopoietic-derived cells mainly responsible for APAP-induced liver injury. Our study confirmed the important role of RIP1 kinase activity in APAP-induced acute liver failure. [Display omitted] • APAP-induced liver injury is significantly attenuated in RIP1 kinase-dead (Rip1 K45A/K45A ) mice. • APAP-induced liver injury is significantly attenuated by RIP1 kinase inhibitor Nec-1 dissolved in PEG400. • RIP1 kinase inactivation reduced the hepatic cell death and inflammation induced by APAP. [ABSTRACT FROM AUTHOR]

Activating the defense response of plants by elicitors provides a promising method for biocontrol of pathogens. The homogeneous octaose (RiOc) which was depolymerized from the succinoglycan Riclin was investigated as a novel elicitor to activate the immune system of potato (Solanum tuberosum L.). After foliar spray, RiOc quickly induced accumulation of reactive oxygen species in potato leaves in a dose-dependent manner. Transcriptomic analysis revealed that 2712 out of 30,863 genes were differentially expressed at the early stage (24 h), while 367 of them were changed later (72 h). Results from the transcriptome and quantitative RT-PCR suggested that RiOc was probably perceived by the receptor LYK3 and it activated the MKK2/3/9/-MPK6/7 signaling cascade and promoted the salicylic acid-mediated defense response. Meanwhile, RiOc changed the metabolome profile of potato leaves over time as demonstrated by the 1H NMR-based metabolomic analysis. Homeostasis of amino acids was affected at the early stage while the secondary metabolism was strengthened later. More importantly, RiOc significantly reduced the severity of potato leaf lesions caused by the late blight pathogen Phytophthora infestans. In conclusion, RiOc effectively improved the resistance of potato to P. infestans by eliciting the salicylic acid-mediated defense response. RiOc becomes a promising carbohydrate-based elicitor for biocontrol of plant pathogens. Key points: • Homogeneous Riclin octaose was a novel elicitor for biocontrol of plant pathogens. • Riclin octaose primed the salicylic acid-mediated defense response of potato plants. • Riclin octaose changed the metabolome profile of potato leaves over time. [ABSTRACT FROM AUTHOR]

Biocontrol of soil-borne pathogens by recruiting soil microbiota brings forth benefits to soil quality and plant production while lowers environmental impact. Succinoglycan possesses various biological activities, but its role in soil amendment is still elusive. The succinoglycan Riclin was investigated in this study as a polysaccharide-type biocontrol agent for improving the soil suppressiveness on a typical fungal pathogen Fusarium oxysporum f. sp. cucumerinum (FOC). Results demonstrated that addition of Riclin increased the soil microbial carbon and lowered the species richness of soil fungal communities. After addition of 2.5 mg/g Riclin for 90 days, the relative abundance of Actinobacteria and Firmicutes were increased by 76.6% and 193.4%, compared with the control. Meanwhile, Proteobacteria and Ascomycota were decreased by 25.9% and 30.4%. The relative abundance of beneficial genera, namely Nocardioides , Kribbella , Streptomyces , Gaiella , Marmoricola , Bacillus , and Rhizobium , became 1.13, 5.17, 0.87, 0.45, 3.57, 4.53, and 6.30 folds higher than the control, respectively. Antagonism towards soil-borne pathogens was probably enhanced as both hydrolase activity and biosynthesis of bioactive secondary compounds were improved. Importantly, Riclin-treated soil significantly reduced the incidence of Fusarium wilt of cucumber seedlings by suppression of FOC. In conclusion, addition of Riclin was conducive to the improvement of soil suppressiveness. • Succinoglycan Riclin lowered the species richness of soil fungal communities. • Riclin accumulated soil plant probiotics to suppress Fusarium wilt of cucumber. • Riclin is a potential carbohydrate-type biocontrol agent for soil amendment. [ABSTRACT FROM AUTHOR]

Lipids produced by oleaginous microorganisms enrich the supply of feedstock for bio-fuel. In this study, a mutant (Mut) obtained by UV-nitrosoguanidine mutagenesis turned its colony color from orange–red to light-yellow and showed higher lipid productivity at 37 °C than the original strain Rhodotorula sp. U13N3 (Rht) in the glycerol medium. The metabolic changes between Mut and Rht in batch fermentation were investigated by transcriptomic and metabolomic profiling at the biomass accumulation (30 h) and lipid production (96 h) stages. The average base number in each strain was 5.80 × 109 ± 0.38 × 109 bp (mean ± SD) with 62.43% ± 0.13% GC ratio, and 7499 unigenes were assembled after Illumina sequencing. Moreover, 33 metabolites were quantified by 1H NMR-based profiling. The multi-omics results demonstrated that Mut showed increased glycerol transport and utilization capabilities especially at the first stage (30 h). Then the carbon flux shifted from the TCA cycle to lipid production (96 h). The increased lipid productivity of Mut was partially attributed to the down-regulation of mannitol biosynthesis. However, the mechanism for color change was elusive. At 96 h, the low level of cytosol glycerol probably restricted the lipid production. As a result, supplementation of glycerol in fed-batch fermentation remarkably improved the biomass, lipid production, and lipid content to 34.60 g/L, 25.72 g/L, and 74.3% (w/w dcw), respectively. The cell morphology implied that excessively prolonging the fermentation time was detrimental to the final lipid yield due to cell breakage. In conclusion, the Rhodotorula mutant provided a candidate strain for lipid production with glycerol as the carbon source. [ABSTRACT FROM AUTHOR]

• A metamaterial film with multilayer structure for laser-compatible infrared stealth is proposed and studied. • The proposed structure simultaneously enables dual-band laser and multi-band infrared compatible stealth along with thermal management which is not realized in previous work. • The design used the high temperature resistant metal Mo rather than the precious metals such as Au or Ag and the multilayer structure makes it possible for large scale fabrication. In this paper, we design a metamaterial film with multilayer structure for laser-compatible infrared stealth. The multilayer film structure is formed by stacking the high-temperature resistant metal Mo and Ge. Numerical results indicate that the absorptivity is 80.42 % and 96.92 % at 1.06 μ m and 1.55 μ m , respectively and the average emissivity of 3 5 μ m and 8 12 μ m atmospheric window bands are lower than 20 %. At the same time, there is a wide-band resonant absorption peak at the 5 ∼ 8 μ m non-atmospheric window band which is beneficial for radiant heat dissipation. The effects of film thickness, polarization of incident light as well as incident angles on stealth performance are studied. The designed structure is only composed of four layers, which is easy to fabricate by film deposition and to realize large-scale integration, and has a very broad application prospect. [ABSTRACT FROM AUTHOR]

Environmental chemicals, such as plasticizers, have been linked to increased rates of obesity, according to epidemiological studies. Acetyl triethyl citrate (ATEC) is a plasticizer that is commonly utilized in pharmaceutical products and food packaging as a non-phthalate alternative. Due to its direct contact with the human body and high leakage rate from the polymers, assessment of the potential risk of ATEC exposure at environmentally relevant low doses to human health is needed. Male C57BL/6 J mice were fed diets containing ATEC at doses of either 0.1 or 10 μg/kg per day in a period of 12 weeks to mimic the real exposure environment. The findings suggest that in C57BL/6 J mice, ATEC exposure resulted in increased body weight gain, body fat percentage, and benign hepatocytes, as well as adipocyte size. Consistent with in vivo models, ATEC treatment obviously stimulated the increase of intracellular lipid load in both mouse and human hepatocytes. Mechanically, ATEC induced the transcriptional expression of genes involved in de novo lipogenesis and lipid uptake. Using both enzyme inhibitor and small interfering RNA (siRNA) transfection, we found that stearoyl-coenzyme A desaturase 1 (SCD1) played a significant role in ATEC-induced intracellular lipid accumulation. This study for the first time provided initial evidence suggesting the obesogenic and fatty liver-inducing effect of ATEC at low doses near human exposure levels, and ATEC might be a potential environmental obesogen and its effect on human health need to be further evaluated. This study for the first time suggested the obesogenic and fatty liver-inducing effect caused by exposure to environmentally-relevant low doses of ATEC plasticizer. [Display omitted] • ATEC increased intracellular lipid load in both murine and human hepatocytes. • Oral exposure to low levels of ATEC led to adipogenesis and fatty liver in mice. • ATEC affected lipid metabolism by altering the expression of related genes. [ABSTRACT FROM AUTHOR]

Levan, a type of β (2→6)-linked fructan, is a promising biopolymer with distinct properties and extensive applications in the fields of food, pharmaceutical, cosmetics, etc. However, the commercial availability of levan is still limited due to the relatively high production costs. Here, a new Paenibacillus sp. strain FP01 was isolated and identified as an efficient fructan producer with high yield (around 89.5 g/L fructan was obtained under 180 g/L sucrose) and conversation rate (49.7%). The fructan named Plev was structurally characterized as a linear levan-type fructan with a molecular mass of 3.11 × 106 Da. Aqueous solutions of Plev exhibited a non-Newtonian behavior at concentrations 3–5%. Heating and chilling had no obvious effects on apparent viscosities of Plev solutions. Plev also had good rheological stabilities toward pH (3–11) and metal salts (Na+, K+, Ca2+, Mg2+). Microbiome and metabolome analysis showed that Plev intervention increased the abundance of beneficial bacteria and elevated the levels of short-chain fatty acids (SCFAs) in feces of mice. Taken together, Plev could be considered a potential thickener and prebiotic supplement in food industry. Key points • Paenibacillus sp. strain FP01 was identified as a high-efficient levan producer. • The levan Plev from FP01 exhibited good rheological properties and stabilities. • The in vivo prebiotic activities of linear levan were revealed. [ABSTRACT FROM AUTHOR]

Metamaterials, as artificially structured materials composed of subwavelength arrays of resonant unit cells, can exhibit exotic properties beyond those accessible to natural materials. They were initially proposed for challenging fundamental laws and demonstrating negative refraction in the microwave regime, and subsequently exploited as a versatile platform to manipulate electromagnetic waves throughout the spectrum via their extreme scalability. Over the past decade, research into metamaterials has been extended to a search for real-world applications, leading to the concept of metadevices, defined as metamaterial-based devices that can operate in an active manner. Due to their subwavelength scale, metamaterials present intriguing strategies for active tuning and provide flat, high-efficiency alternatives to conventional optical systems based on bulky components. In this topical review, we summarize the development of active metamaterials and metadevices ranging from microwave to visible wavelengths, including milestones as well as the state of the art. We survey tuning strategies based on mechanical reconfiguration and incorporation with active materials such as varactor diodes, semiconductors, liquid crystals, phase change materials, superconductors, and two-dimensional materials under various external stimuli, and discuss their fascinating advantages and potential challenges to be confronted. Finally, future prospects together with several emerging tuning strategies and materials are presented at the end. [ABSTRACT FROM AUTHOR]

This study aims to explore the production and physicochemical properties of an exopolysaccharide (EPS) produced from soil isolate, Paenibacillus sp. ZX1905 in submerged culture. The highest EPS production of 15.67 g/L was achieved in a medium containing soluble starch, peptone and inorganic salts. The purified EPS exhibited excellent skin lubricating properties and was named lubcan. The chemical analysis reviewed that lubcan was an acidic heteropolysaccharide consisted of glucuronic acid, glucose, mannose, galactose, and rhamnose in a molar ratio of 2:3:1:2:2, and the average molecular mass was about 3.27 × 106 Da. NMR and methylation analysis revealed that lubcan backbone was composed of 1,4-α-Man, 1,4,6-α-Glc, 1,3-α-Gal, 1,3-β-Rha, and 1,3-β-Gal, together with the branches of 1,3-α-Glc, 1,3-α-Rha, two 1,4-α-GlcA, and terminal-α-Glc(4,6-pyr). The lubcan solution exhibited stability at pH ranging from 5.0 to 7.0, temperature between 5 and 50 °C, and monovalent salts (0.2 M) and divalent salts (0.05 M) addition. The moisture absorption rates of lubcan were 16.98% and 40.41% under the conditions of 43% and 81% relative humidity, which were close to that of hyaluronic acid (17.28% and 41.20%, respectively). These properties make lubcan a good alternative to more expensive hyaluronic acid in the cosmetic industry. • An acidic exopolysaccharide lubcan was produced by Paenibacillus sp. ZX1905. • Lubcan was composed of GlcA, Glc, Man, Gal, and Rha in a ratio of 2:3:1:2:2. • Lubcan exhibited great skin lubricating properties. • Lubcan showed excellent moisture absorption and holding capacities. [ABSTRACT FROM AUTHOR]

Infectious diseases such as Listeria monocytogenes infection pose a great threat to the health of human beings and the development of livestock and poultry farming. Currently the treatment of Listeria infection mainly relies on antibiotics, which may result in excessive antibiotic residues in livestock and poultry products, as well as causing an increase in the occurrence of zoonotic diseases. Here, we demonstrate that Succinoglycan Riclin promoted the clearance of Listeria in the in vitro and in vivo infection model. The expression and secretion of inflammatory cytokines including IL-6 and IL-1β were significantly increased after Riclin treatment upon infection. The protective effect of Riclin was mainly through activating MAPK/IL-6 axis. HO-1/IL-1β signaling pathway was less important in this process. Moreover, Riclin caused significant metabolic changes including pathways involved in glycolysis, protein synthesis and oxidative stress during Listeria infection. These results suggest a potential use of Succinoglycan Riclin as non-antibiotic preventive and therapeutic anti-microbial agent in livestock and poultry farming and human diseases. [ABSTRACT FROM AUTHOR]

Vulvovaginal candidiasis (VVC) is one of the most common infections in women. The purpose of this study was to evaluate the ability of a water-soluble β-glucan salecan to protect against Candida albicans (C. albicans) vaginal infection. The model was reproduced with intravaginal inoculation of yeast blastoconidia in pseudoestrus mice. We found that mice that received salecan (0.5 mg per mouse) after infection had 85% fewer CFU than infected mice given saline. Compared with the C. albicans group, salecan reduced the migration of polymorphonuclear neutrophils (PMNs) in the vagina, decreased mRNA levels of cytokines IL23 , IL22 , IL17a , and IL17f , anti-candidal genes S100a8 and S100a9 and C. albicans pattern recognition receptor Dectin1. The analysis for vaginal microbial community composition at different taxa levels revealed that the bacterial flora composition in the vagina of the salecan-treated mice was similar to that of the uninfected mice, and distinguished from the infected mice. The vaginal lavages from the salecan treated group had more Enterococcus and its metabolite lactate. Our results suggest salecan might be a potential therapeutic agent for vaginal infection of C. albicans. [ABSTRACT FROM AUTHOR]

The formation and hydrolysis of hepatic retinyl esters (RE) is a key process in maintaining serum retinol homeostasis. During vitamin A deficiency, the activity of RE hydrolases (REH) in liver increases to cope with the reduced dietary vitamin A intake. However, it remains unclear which REH is the main enzyme responsible for RE hydrolysis in the liver under physiological conditions. Our previous studies have shown that pancreatic lipase‐related protein 2 (PLRP2) is conditionally expressed in the liver and may be involved in the hydrolysis of hepatic RE. In the current study, we generated Plrp2−/− mice using transcription activator‐like effector nuclease technology to investigate the role of PLRP2 in the metabolism of hepatic RE. Compared with the mice fed normal diet, the hepatic REH activity of wild‐type (WT) mice fed vitamin A‐deficient diet (VAD) increased significantly, while this activity did not increase in Plrp2−/− mice fed VAD. Plrp2−/− mice showed higher residual RE content in liver and lower serum retinol level, compared with WT mice fed VAD. Hepatic metabolic profiling from 1H NMR‐based metabolomics suggested that Plrp2−/− mice were more sensitive to VAD. Docking analysis and enzyme activity assay revealed that retinyl palmitate was the substrate with higher affinity for PLRP2. Our results indicate that Plrp2 can be activated in the liver and is responsible for the increased REH activity in the liver of mice fed VAD. [ABSTRACT FROM AUTHOR]

Xyloglucans and mixed-linkage β-glucans are the major components of hemicelluloses in lignocellulosic biomass. In this study, a novel β-1,4-glucanase Pgl5A belonging to the glycoside hydrolase family 5 subfamily 4 (GH5_4), was identified from Paenibacillus sp. S09. Pgl5A is a 70.9-kDa protein containing an N-terminal GH5_4 module, a carbohydrate-binding module (CBM)_X2 and a CBM3. Full-length Pgl5A and its CBM deletion mutants Pgl5A∆C and Pgl5A-CD were expressed in E. coli. All three enzymes showed maximal activity at 55 °C and pH 4.5–5.0, and possessed similar activity toward xyloglucan, barley β-glucan, and lichenan. Deletion of the CBM modules can improve thermostability and acid-tolerant properties of Pgl5A. Circular dichroism (CD) and intrinsic fluorescence spectroscopy analysis verified that C-terminus truncation improves the enzyme acid-tolerant properties. Homology modeling and CD spectra indicated that Pgl5A has an architectural (β/α) 8 fold of GH5_4 enzymes. The catalytic efficiency (k cat / K m) of Pgl5A toward xyloglucan, but not mixed-linkage β-glucan, was reduced due to C-terminus truncation. TLC and LC-MS analysis showed that Pgl5A cleaves xyloglucan and mixed-linkage β-glucan into a series of xyloglucan oligosaccharides and gluco-oligosaccharides, respectively. The favorable enzymatic characteristics and high catalytic activities toward both xyloglucan and mixed-linkage β-glucan make Pgl5A a promising candidate for biotechnological industrial applications. [ABSTRACT FROM AUTHOR]

Food freshness monitoring is vital to ensure food safety. Recently, packaging materials incorporating pH-sensitive films have been employed to monitor the freshness of food products in real time. The film-forming matrix of the pH-sensitive film is essential to maintain the desired physicochemical functions of the packaging. Conventional film-forming matrices, such as polyvinyl alcohol (PVA), have drawbacks of low water resistance, poor mechanical properties, and weak antioxidant ability. In this study, we successfully synthesise PVA/riclin (P/R) biodegradable polymer films to overcome these limitations. The films feature riclin, an agrobacterium -derived exopolysaccharide. The uniformly dispersed riclin conferred outstanding antioxidant activity to the PVA film and significantly improved its tensile strength and barrier properties by forming hydrogen bonds. Purple sweet potato anthocyanin (PSPA) was used as a pH indicator. The intelligent film with added PSPA provided robust surveillance of volatile ammonia and changed its color within 30 s in the pH range of 2–12. This multifunctional colorimetric film also engendered discernible color changes when the quality of shrimp deteriorated, demonstrating its great potential as an intelligent packaging material to monitor food freshness. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: Methotrexate (MTX) is a widely used cancer chemotherapy agent. The efficacy of MTX is often limited by serious side effects, such as intestinal mucositis. The aim of this study was to evaluate the protective effect of water-soluble β-glucan salecan on MTX-induced intestinal toxicity in mice.Methods: Intestinal mucositis was induced in C57BL/6 mice by intraperitoneal injection of MTX for two consecutive days. Mice were orally administrated with saline or salecan for 6 days before MTX injection and continued to the end of the study. Several histological and biochemical parameters were measured in the jejunum.Results: Orally administration of salecan improved the severity of intestinal mucositis in a dose-dependent manner, as evidenced by the well-maintained mucosal architecture and body weight in salecan-treated groups. Salecan treatment inhibited MTX-induced oxidative stress and effectively scavenged free radicals both in vitro and in vivo. Metabolomics analysis revealed that salecan treatment reversed the intestinal metabolic profiling changes in mice with MTX-induced mucositis. Salecan treatment modulated the innate immunity through the regulation of TLR and Dectin1 expression in the jejunum, thus protecting mice from MTX-induced intestinal damage.Conclusions: Salecan has potential advantages in the treatment of MTX-induced intestinal mucositis, and its protective effect is mainly attributed to its antioxidant and immunomodulatory properties. [ABSTRACT FROM AUTHOR]

Abstract Tributyltin (TBT), a widely distributed environmental pollutant, is toxic to animals and human beings. Although its toxicity, especially the immunosuppressive effect, has been reported a lot, the underlying molecular mechanisms are still unclear. In this study, we investigated the mechanisms of TBT-induced cytotoxicity both in vitro and in vivo. TBT induced cell death in both J774A.1 macrophages and mouse bone marrow-derived macrophages (BMDMs) as measured by the LDH and Annexin V-FITC/PI dual staining assays. Pretreatment with RIP1 inhibitor Necrostatin-1 (Nec-1) or transfection with Rip1 siRNA significantly suppressed TBT-induced cytotoxicity in J774A.1 macrophages or human embryonic kidney cell line (HEK293 cells). TBT-induced cell death was also markedly inhibited in RIP3 −/− BMDMs. In agreement with in vitro results, TBT-induced in vivo immunotoxic effects including leukocyte depletion and thymus atrophy were significantly attenuated in RIP3 −/− mice or WT mice treated with Nec-1. Notably, the mortality rate induced by TBT was remarkably reduced in RIP3 −/− mice (100% vs. 12.5% lethality) or Nec-1-treated mice (100% vs. 59.2% lethality) respectively. These results reveal a critical role of RIP1 and RIP3 in TBT-induced toxicity both in vitro and in vivo. Highlights • TBT-induced cell death was significantly downregulated by RIP1 inhibition or knockdown, or RIP3 deficiency. • The mortality induced by acute TBT exposure was markedly reduced by RIP1 inhibitor pretreatment or RIP3 deficiency. • The immunotoxic effects induced by TBT were attenuated in RIP3 −/− mice or WT mice treated with RIP1 inhibitor. [ABSTRACT FROM AUTHOR]

Abstract Salecan is a water-soluble extracellular β‑glucan and appropriate for preparing hydrogels applicable in biomedical field. Herein, an innovative photocrosslinked composite hydrogel composed of salecan/poly(hydroxypropyl methacrylate (PHPMA) network and titanium carbide (TiC) nanoparticles was successfully prepared. XRD patterns clearly showed the crystal planes of Ti. More importantly, the introduction of TiC nanoparticles into the hydrogel network provided structural reinforcement, and thereby synergistically enhanced the mechanical strength and thermal stability of the hydrogels. The change of salecan content markedly affected the swelling behavior and morphology of the composite hydrogels. Cytotoxicity results revealed that the composite hydrogels were non-toxic to L929 and 3T3L1 cells. Cell proliferation and Live/Dead assay further demonstrated excellent cytocompatibility of the cells within the composite hydrogels, which highlights the value of this system for potential application as soft tissue engineering scaffold. [ABSTRACT FROM AUTHOR]

Salecan, a water-soluble extracellular β-glucan, has emerged as a promising candidate for preparing hydrogel biomaterials recently. Herein, photo cross linked composite hydrogels, composed by salecan/poly ( N-tert -butylacrylamide-co-acrylamide) network andα-Mo 2 C nanoparticles were prepared by ultraviolet (UV) light, using Irgacue 2959 as photo initiator. The XRD and EDX analysis illustrated the presence of embeddedα-Mo 2 C nanoparticles throughout the hydrogel matrix. Compression tests and thermal analysis revealed that the incorporation of α-Mo 2 C nanoparticles enhanced mechanical strength and thermal stability due to the structural reinforcement of the composite hydrogels. Moreover, the change of salecan content provided a mean to tailor both the swelling property and morphology of the composite hydrogels. Encapsulation of L929 and 3T3-L1 cells and the following viability test showed the excellent cell-compatibility of these hydrogels. Taken together, these studies support the use of photo crosslinked composite hydrogels as tunable biomaterials for cell adhesion. [ABSTRACT FROM AUTHOR]

Abstract Piceatannol, a natural derivative of resveratrol, has been shown to exert similar anti-oxidant and anti-inflammatory effects as resveratrol. However, it remains unknown whether piceatannol has hepatoprotective effect against acute liver injury. In this study, we investigated the in vivo effect of piceatannol on D-GalN/LPS-induced fulminant hepatic failure (FHF), and its in vitro effect on ER stress-inducing drug thapsigargin (TG)-induced proinflammatory cytokines production and ROS release. Our results indicated that piceatannol markedly decreased the mortality rate, reduced the serum levels of alanine transaminase and aspartic aminotransferase, ameliorated the liver damage induced by D-GalN/LPS in mice. In addition, piceatannol reduced the expression of proinflammatory cytokines, including TNF-α, IL-1β and IL-6, the expression of ER stress markers CHOP and phosphorylated-IRE1α, and the generation of oxidative stress in D-GalN/LPS-treated mouse liver. In vitro results were consistent with in vivo observations, demonstrating that piceatannol suppressed the secretion of proinflammatory cytokines, inflammasome activation and the production of ROS induced by TG with or without LPS priming in J774A.1 macrophages. Our study proposes piceatannol as a promising medication for preventing acute liver failure and the mechanisms may be related to its inhibitory effects on ER stress, inflammation and oxidative stress. Highlights • Piceatannol protects against D-GalN/LPS-induced acute liver injury. • Piceatannol decreases D-GalN/LPS-induced oxidative stress, inflammation and ER stress in liver. • Piceatannol inhibits the ROS production and inflammasome activation by ER stress inducer in macrophages. • Piceatannol reduces the oxidative stress, ER stress and liver damage induced by ER stress-inducing chemical in vivo. [ABSTRACT FROM AUTHOR]

Abstract A novel magnetic field-sensitive composite hydrogel was prepared by microwave-assisted polymerization of salecan and 3-acrylamidopropyl trimethylammonium chloride in the presence of Fe 3 O 4 @tannic acid (TA) nanoparticles. FT-IR spectroscopy confirmed the formation of the copolymer structure. XRD patterns clearly showed the crystal planes of Fe. TGA verified that incorporation of Fe 3 O 4 @TA nanoparticles into the copolymer matrix greatly enhanced the thermal stability of the composite hydrogel. The water uptake, retention, saturation magnetization and pore size can be well modulated by changing Fe 3 O 4 @TA content. More importantly, mechanical tests revealed that the compressive and storage moduli were significantly improved by the introduction of Fe 3 O 4 @TA nanoparticles or application of external magnetic field, probably due to the particles alignment and subsequent structural rearrangement of polymer chains under the magnetic field. The reinforcement mechanism reported here offers a universal strategy for enhancing the comprehensive mechanical properties of polysaccharide-based materials. Highlights • The hydrogels were obtained from salecan/PAPTAC copolymer and Fe 3 O 4 @TA nanoparticles by microwave-assisted polymerization. • The XRD analysis confirmed the presence of Fe 3 O 4 @TA nanoparticles throughout the hydrogels matrix. • Effect of Fe 3 O 4 @TA content on water uptake, retention, saturation magnetization and pore size of the hydrogels was tested. • The incorporation of Fe 3 O 4 @TA nanoparticles significantly enhanced compressive modulus and storage modulus of the hydrogels. • The compressive modulus and storage modulus of the hydrogels were greatly improved by applying an external magnetic field. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Salecan-containing cationic hydrogels were designed for adsorption of dye. • Salecan-containing gels were prepared via radical polymerization technique. • Effect of salecan content on the hydrogel properties were studied. • Effect of salecan content on the adsorption behaviors were evaluated. Abstract With advances in soft material design and engineering, naturally resourced polysaccharides have frequently been used to construct hydrogels because of their unique properties such as renewability, biodegradability and biocompatibility. In this work, we use a water-soluble microbial polysaccharide, salecan as a trapped natural polymer, poly(acrylamide-co-diallyldimethylammonium chloride) (PAD) as a functional matrix to prepare salecan/PAD hydrogels through a facile one-pot method. We employed a variety of spectroscopic techniques to probe the physicochemical properties of the designed hydrogels. The results demonstrated that salecan not only tuned the polarity of the PAD hydrogels, but also endowed them with adjustable water content. Subsequently, the adsorption performance of these hydrogels to methyl orange (MO) dye was investigated in detail. It was found that the salecan/PAD had the ability to remove MO from the surrounding aqueous solutions. In addition, adsorption kinetic data were nicely described by pseudo-second-order model and the adsorption isotherm data fitted well with the Freundlich equation. Having tailorable physicochemical properties coupled with the ability to uptake dye, these salecan-incorporated hydrogels could be promising platform for wastewater treatment and removal of heavy metal ions. [ABSTRACT FROM AUTHOR]