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Dendrobium officinale Kimura et Migo (D. officinale) is used as herbal medicine and new food resource in China, which is nontoxic and harmless, and can be used as common food. Polysaccharide as one of the main bioactive components in D. officinale, mainly composed of glucose and mannose (Manp: Glcp = 2.01:1.00-8.82:1.00), along with galactose, xylose, arabinose, and rhamnose in different molar ratios and types of glycosidic bonds. Polysaccharides of D. officinale exhibit a variety of biological effects, including immunomodulatory, anti-tumor, gastro-protective, hypoglycemic, anti-inflammatory, hepatoprotective, and vasodilating effects. This paper presents the extraction, purification, structural characteristics, bioactivities, structure-activity relationships and analyzes gaps in the current research on D. officinale polysaccharides. In addition, based on in vitro and in vivo experiments, the possible mechanisms of bioactivities of D. officinale polysaccharides were summarized. We hope that this work may provide helpful references and promising directions for further study and development of D. officinale polysaccharides.

The influence of polystyrene particles with different nanoscale roughnesses on the morphology of polyisobutylene/polydimethylsiloxane blends was studied under shear flow by using confocal laser scanning microscopy. It was found that the surface roughness of particles strongly affected their diffusion and distribution behaviors, thereby determining the size and spatial arrangement of droplets in the blends. The roughness effect of particles was found to possess a strong dependence on both the blend ratio and the shear rate. The result suggested that the particle roughness can serve as a new parameter to control the structure-property correlation in particle-filled polymer blends, especially under slow flow.

Photocatalytic CO2 fixation is widely considered as a promising approach for recycling carbon-based energy resources. However, it is still beyond practical application due to the low efficiency and...

The Ediacaran Period was characterised by major carbon isotope perturbations. The most extreme of these, the ∼570 Ma Shuram/DOUNCE (Doushantuo Negative Carbon isotope Excursion) anomaly, coincided with early radiations of benthic macrofauna linked to a temporary expansion in the extent of oxygenated seawater. Here we document an earlier negative excursion (the ∼610 Ma WANCE (Weng'An Negative Carbon isotope Excursion)) anomaly in the Yangtze Gorges area, South China, that reached equally extreme carbon isotope values and was associated with a similar degree of environmental perturbation. Specifically, new uranium isotope data evidence a significant, but transient, shift towards more oxygenated conditions in tandem with decreasing carbon isotope values, while strontium and sulfur isotope data support an increase in continental weathering through the excursion. We utilize a biogeochemical modelling approach to demonstrate that the influx of such a weathering pulse into an organically-laden, largely anoxic ocean, fully reproduces each of these distinct isotopic trends. Our study directly supports the hypothesis that a large dissolved marine organic pool effectively buffered against widespread oxygenation of the marine environment through the Proterozoic Eon, and in doing so, substantially delayed the radiation of complex aerobic life on Earth.

Rhodamine spirolactams with adjacent amino groups work as acid-resistant and photoswitchable fluorophores in single-molecule localization super-resolution imaging., Rhodamine spirolactam based photoswitches have been extensively applied in super-resolution single-molecule localization microscopy (SMLM). However, the ring-opening reactions of spirolactams are cross-sensitive to acid, limiting their photoswitch use to neutral pH conditions. In addition, the ring-closing reactions of spirolactams are environment-sensitive and slow (up to hours), virtually making rhodamine spirolactams caged fluorescent dyes instead of reversible photoswitches in SMLM. Herein, by introducing hydrogen bonds to stabilize spirolactams, we report a series of acid-resistant rhodamine spirolactams with accelerated ring-closing reactions from fluorescent xanthyliums to non-fluorescent spirolactams, endowing them with good photoswitchable properties even in acidic environments. By further substitution of 6-phenylethynyl naphthalimide on the spirolactam, we shifted the photoactivation wavelength into the visible region (>400 nm). Subsequently, we have successfully applied these dyes in labeling and imaging the cell surface of Bacillus subtilis at pH 4.5 using SMLM.

Objective The goal of this study was to analyze the impact of cas3 gene on the biofilm formation and virulence gene expression in S. mutans, since our previous studies have found a connection between CRISPR/Cas systems and biofilm formation in S. mutans. Methods The cas3 gene in-frame deletion strains of S. mutans UA159 was constructed by a two-step transformation procedure and the cas3 mutant strain was complemented in trans. The biofilm biomass was measured by crystal violet staining, and the synthesis of exopolysaccharides (EPS) was measured by the anthrone-sulfuric method. Biofilm analysis and structural imaging was using confocal laser scanning microscope (CLSM) and scanning electron microscope (SEM) assays. The fluorescence in situ hybridization (FISH) was used to analyze the spatiotemporal interactions between S. mutans and Streptococcus sanguinis. Fluoride sensitivity was determined using fluoride tolerance assays. The expression of biofilm formation related genes was evaluated by qRT-PCR. Results Our results showed that S. mutans cas3 deletion strain formed less biofilm and became less competitive when it was co-cultured with S. sanguinis under fluoride treatment. The expression levels of virulence genes including vicR, gtfC, smu0630 and comDE were significantly downregulated. Conclusions The cas3 gene in S. mutans could regulate biofilm formation and fluoride resistance, consequently affecting S. mutans competitiveness in a dual-species biofilm model under fluoride treatment. These results also provide a potential strategy for enhancing fluoride specificity, with cas3 gene as a potential genetic target in the modulation of oral microecology and the treatment of dental caries.

D‐Amino acid oxidase (DAAO) specifically catalyzes the oxidative deamination of neutral and polar D‐amino acids and finally yields byproducts of hydrogen peroxide. Our previous work demonstrated that the spinal astroglial DAAO/hydrogen peroxide (H2O2) pathway was involved in the process of pain and morphine antinociceptive tolerance. This study aimed to report mouse strain specificity of DAAO inhibitors on antinociception and explore its possible mechanism. DAAO inhibitors benzoic acid, CBIO, and SUN significantly inhibited formalin‐induced tonic pain in Balb/c and Swiss mice, but had no antinociceptive effect in C57 mice. In contrast, morphine and gabapentin inhibited formalin‐induced tonic pain by the same degrees among Swiss, Balb/c and C57 mice. Therefore, mouse strain difference in antinociceptive effects was DAAO inhibitors specific. In addition, intrathecal injection of D‐serine greatly increased spinal H2O2 levels by 80.0% and 56.9% in Swiss and Balb/c mice respectively, but reduced spinal H2O2 levels by 29.0% in C57 mice. However, there was no remarkable difference in spinal DAAO activities among Swiss, Balb/c and C57 mice. The spinal expression of glutathione (GSH) and glutathione peroxidase (GPx) activity in C57 mice were significantly higher than Swiss and Balb/c mice. Furthermore, the specific GPx inhibitor D‐penicillamine distinctly restored SUN antinociception in C57 mice. Our results reported that DAAO inhibitors produced antinociception in a strain‐dependent manner in mice and the strain specificity might be associated with the difference in spinal GSH and GPx activity., Effects of DAAO inhibitors (CBIO, benzoic acid and SUN) were compared between Swiss, Balb/c and C57 mice in formalin test. The results showed that the DAAO inhibitors significantly inhibited formalin‐induced tonic pain in Balb/c and Swiss mice, but had no effect in C57 mice.

Among cariogenic microbes, Streptococcus mutans is considered a major etiological pathogen of dental caries. Lactobacilli strains have been promoted as possible probiotic agents against S. mutans, although the inhibitory effect of Lactobacilli on caries has not yet been properly addressed. The objective of this study was to screen Lactobacillus strains found in traditional Sichuan pickles and to evaluate their antagonistic properties against S. mutans in vitro and in vivo. In the current study, we analyzed 54 Lactobacillus strains isolated from pickles and found that strain L. plantarum K41 showed the highest inhibitory effect on S. mutans growth as well as on the formation of exopolysaccharides (EPS) and biofilm in vitro. Scanning electron microscopy (SEM) and confocal laser scanning microscope (CLSM) revealed the reduction of both EPS and of the network-like structure in S. mutans biofilm when these bacteria were co-cultured with strain L. plantarum K41. Furthermore, when rats were treated with strain L. plantarum K41, there was a significant reduction in the incidence and severity of dental caries. Due to K41’s origin in a high salinity environment, it showed a high tolerance to acids and salts. This may give this strain an advantage in harsh oral conditions. Results showed that L. plantarum K41 isolated from traditional Sichuan pickles effectively inhibited S. mutans biofilm formation and thus possesses a potential inhibitory effect on dental caries in vivo.

TLR3 is implicated in anti-viral immune responses, but may also act as a sensor of tissue damage in the absence of infection. Here, we provide evidence for an essential role of TLR3 in liver regeneration after an acute loss of tissue due to partial hepatectomy. Mice lacking TLR3 had a severe and sustained defect in the restoration of liver tissue with reduced liver-to-body weight ratios even after an extended recovery period of 2 weeks. Hepatocyte cell cycle progression into S phase was impaired in TLR3-deficient mice. Mechanistic analyses revealed that TLR3-deficient mice had markedly reduced systemic levels of active HGF, but had increased amounts of inactive tissue-bound HGF. Importantly, expression of uPA, which orchestrates the processing and release of HGF from the hepatic extracellular matrix, was reduced in regenerating livers of TLR3-deficient mice. In addition, expression of the HGF maturation factor HGFAC was transiently diminished in TLR3-deficient mice. In vitro, engagement of TLR3 directly stimulated expression of uPA by hepatic stellate cells. Thus, TLR3 supports liver regeneration through upregulation of uPA, which promotes the release of preformed HGF from extracellular matrix stores.

Ethnopharmacological relevance Cedrus deodara (Roxb. ex D.Don) G. Don is applied as anti-inflammatory and anti-infection agents in folklore medicine. Aim of the study The present study aimed to assess the antimicrobial activity of Cedrus deodara (Roxb. ex D.Don) G. Don extract (CDE) against Streptococcus mutans biofilm formation and its biocompatibility, as well as to identify its chemical components. Materials and methods Confocal laser scanning microscopy (CLSM), crystal violet staining, and CFU counting assay were applied to investigate the effect of CDE on S. mutans biofilm formation and extracellular polysaccharides (EPS) synthesis. The microstructure of S. mutans biofilms formed on glass coverslips and bovine enamel treated with CDE was observed by scanning electron microscopy (SEM). qRT-PCR was used to measure the expression of virulence genes gtfB, gtfC, and gtfD, and zymogram assay was performed to investigate the enzymatic activity of Gtfs. Moreover, HPLC-MS and NMR were applied to identify its chemical components. CCK-8 assay was also performed on human oral cells to evaluate its biocompatibility. Results Under the treatment of CDE, S. mutans formed less biofilm on both coverslips and enamel surfaces and synthesized less EPS. Moreover, CDE downregulated the expression of gtf genes and inhibited the enzymatic activity of Gtfs. According to HPLC-MS and NMR results, molecular structures of six main compounds in CDE were identified. CDE also has a good biocompatibility. Conclusions CDE exhibits inhibitory activity against S. mutans and a good biocompatibility. It has the potential to be developed as anti-caries agents for clinical use.

This study proposed a low-cost sensor for in situ automatic monitoring of phosphate and nitrite in agricultural water environments, involving a series of "Fish-Bite" reservoirs, multiple reagent capsules, and a colorimetric sensor. The Fish-Bite reservoir is an alternative to the pumps, valves, and filters that are widely used for water sample collection and also offers a closed cell for chromogenic reactions afterward. Up to two capsules can be embedded in each reservoir to support chromogenic reactions that use two different reagents in sequence. From the results of calibration tests in the laboratory, the limit of detection was found to be approximately 0.01 mg/L for both phosphate and nitrite, with a linear range of 0.01-1.00 mg/L for phosphate and 0.01-0.20 mg/L for nitrite. Furthermore, an in situ experiment was successfully carried out in an irrigation canal beside farmland to demonstrate the practicability and robustness of the device. The averaged concentrations of phosphate and nitrite were 0.0113 mg/L and 0.0383 mg/L, respectively. The relative deviations were 20.2% and 11.7%, respectively, referred to results obtained by using the standard spectrophotometric methods. With the advantages of being robust, fast, and low cost, this in situ device is promising for the formation of agricultural sensor networks.

The effectiveness of liver regeneration limits surgical therapies of hepatic disorders and determines patient outcome. Here, we investigated the role of the neuropeptide calcitonin gene-related peptide (CGRP) for liver regeneration after acute or chronic injury. Mice deficient for the CGRP receptor component receptor activity-modifying protein 1 (RAMP1) were subjected to a 70% partial hepatectomy or repeated intraperitoneal injections of carbon tetrachloride. RAMP1 deficiency severely impaired recovery of organ mass and hepatocyte proliferation after both acute and chronic liver injury. Mechanistically, protein expression of the transcriptional coactivators Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) was decreased in regenerating livers of RAMP1-deficient mice. Lack of RAMP1 was associated with hyperphosphorylation of YAP on Ser127 and Ser397, which regulates YAP functional activity and protein levels. Consequently, expression of various YAP-controlled cell cycle regulators and hepatocyte proliferation were severely reduced in the absence of RAMP1. In vitro, CGRP treatment caused increased YAP protein expression and a concomitant decline of YAP phosphorylation in liver tissue slice cultures of mouse and human origin and in primary human hepatocytes. Thus, our results indicate that sensory nerves represent a crucial control element of liver regeneration after acute and chronic injury acting through the CGRP-RAMP1 pathway, which stimulates YAP/TAZ expression and activity.

The development of portable and wearable electronic devices has substantially increased the demand for printed circuit boards with high thermal conductivity, optimal mechanical flexibility, electrical insulativity, and minimal high-frequency transmission loss. Herein, we demonstrate the fabrication of a thermally conductive, flexible composite paper, for electronic and microwave devices, based on hexagonal boron nitride nanosheets, poly(vinyl alcohol) (PVA), and fiberglass mesh (FGM). The prepared composite paper exhibits in-plane thermal conductivity of 22.51 W/(m·K), and the FGM induced high mechanical strength of 27.92 MPa. The transmission loss, of the grounded coplanar waveguide lines, was 0.10 dB/mm at 7.0 GHz, and shows negligible variation while bending, indicating the high flexibility of the circuit board. These results demonstrate potential application of BN-based composite paper in flexible electronic devices.

A low-cost, compact, pumpless and valveless device is proposed in this study for water quality in field detection. Capsules filled with chromogenic reagent were fixed inside reservoirs. A series of reservoirs were mounted on a revolver. The device can automatically open the reservoirs and the capsule, so that the water sample can come inside then mix and react with the chromogenic reagent. During the reactions, the color data of samples were recorded dynamically and the chromogenic reaction rate constants were derived. According to different reaction rate constants, the concentration of target substance can be determined since the concentration and rate constant are positively correlated. A prototype was built and experiments were carried out to determine concentration of a typical nutrient, nitrite, in water samples to evaluate the effectiveness of the device. It was found that the limit of detection (LOD) for nitrite was approximately 0.01 mg/L. With minor modification, the device can be used to monitor quality parameters in natural water, and wastewater from sewage, agriculture, fishery or industry.

Commercial 3D reticular nickel foam and its composite structure were investigated on the sound absorption at 200-2000 Hz. The absorption performance of foam plates 1-5 layers (1-layer thickness: 2.3 mm; porosity: 89%; average pore-diameter: 0.57 mm) was found to be poor, and could be improved by adding backed cavum or front perforated thin sheet. The absorption coefficient could reach about 0.4 at 1000-1600 Hz for the composite structure of 5-layer foam with a backed 5 mm-thick cavum, and even 0.68 at about 1000 Hz for that of 2-layer foam with the same cavum and a perforated plate closely in front of the foam.

A one-dimensional metal organic oxide of Mn(II), with formula [Mn3(OH)2(Hpdc)2]n (H3pdc = 3,5-pyrazoledicarboxylic acid), was prepared via the hydrothermal method and its structure solved by single-crystal X-ray diffraction. The compound exhibits a three-dimensional framework structure, comprising three crystallographically unique Mn atoms bridged by OH ligands (O9 and O10) and O atoms from the Hpdc ligands, forming one-dimensional metal–organic oxide chains. Two kinds of magnetic exchange are observed: a strong antiferromagnetic intra-chain interaction, arising from the short distance between Mn(II) centers, and a ferromagnetic inter-chain interaction, due to the larger distances between the chains. The compound shows good photocatalytic activity for the decomposition of methylene blue in aqueous medium under simulated sunlight.

A reduced graphene oxide (RGO) based capacitive real time bio-sensor was presented. Suspended graphene oxide (GO) film was assembled electrophoretically between the source and drain electrodes of a transistor and then reduced by annealing in hydrogen/nitrogen forming gas to optimize the surface functional groups and conductivity. The resonance frequency of the transmission coefficient (S21) of the transistor was observed to shift with deoxyribonucleic acid (DNA)-hybridization, with a detecting limit of ~ 5 nM. The advantages of the bio-sensing approach include low-noise frequency output, solution based real time detection and capable of on-chip integration.

Copper (Cu)-containing bioactive glasses (BGs) are attracting attention for bone regeneration and wound healing since they have bone-bonding capability and potential osteogenesis and angiogenesis properties. In this study, highly dispersed and spherical Cu-containing bioactive glass nanoparticles (Cu-BGNs) were successfully synthesized via a modified Stöber method. The content of incorporated Cu in the particles could be tailored by adjusting the amount of the added Cu precursor, a procedure that had no significant effects on the morphological and structural characteristics of the nanoparticles. Cu-BGNs exhibited satisfactory apatite-forming ability, as a large quantity of apatite could form on Cu-BGNs pellets after immersion in simulated body fluid for just 3days. The incorporation of Cu exhibited positive effects on the apatite formation. In addition, both Si and Cu ions were released from the Cu-BGN in a sustained manner for at least 14days in cell culture medium, indicating the potential of the BGN as promising carriers for delivering therapeutic Cu ions. Moreover, Cu-BGNs showed no significant cytotoxicity towards human mesenchymal stem cells and fibroblast cells at concentrations of 100, 10 and 1μg/mL. Taken together, the results suggest that Cu-BGNs are promising nanoparticulate fillers to develop nanocomposites for biomedical applications especially in bone regeneration and wound healing.

Unique nanoporous Co3O4 fibres and sheets were successfully fabricated via a facile hydrothermal route (150 °C) and subsequent annealing process at 500 °C in air. The excellent microwave absorption of the nanoporous Co3O4 materials originates not only from the dielectric loss and impedance matching, but also from geometrical effects. Herein, the photocatalytic behavior of the as-prepared Co3O4 has also been reported based on the degradation of methylene blue (MB) dye in an aqueous medium under simulated solar light.

This research introduced a new low-cost and multi-parameter analyzer for in-situ measurements of typical nutrients in water bodies. The analyzer consisted of color detection and chromogenic reaction modules. The self-sampling action of the 3D printed sampling/reaction cells was achieved with the cooperative application of rubber bands and dissolvable thread. The target analytes in the collected water sample reacted with the chromogenic reagents that were diffused from the pre-placed glass wool in the cell, producing color compounds. A portable document scanner was employed as a multi-parameter in-situ detector to record the image of the colored solutions in all five cells simultaneously. Based on the image, the corrected grayscale values were derived for target analyte quantitation. The relationships between grayscale values and concentrations of target analytes were established, and the temperature effects were studied. In addition, the practicability of the analyzer was demonstrated by in-situ experiments carried out in four different sites, including a creek, a river dock, a reservoir and a secondary settling tank in a wastewater treatment facility. The results indicated that the analyzer could be used for in-situ measuring of nutrients at μmol/L levels in the water. The nutrient concentrations obtained with the analyzer were comparable with those obtained with the standard methods. The presented analyzer provided new complementary ideas and methods for in-situ rapid measurement of nutrients and other target analytes in various water systems.

Brahma-related gene 1 (Brg1), a catalytic subunit of the SWItch/Sucrose Non-Fermentable (SWI/SNF) complex, is known to be involved in proliferative cell processes. Liver regeneration is initiated spontaneously after injury and leads to a strong proliferative response. In this study, a hepatocyte-specific Brg1 gene knockout mouse model was used to analyse the role of Brg1 in liver regeneration by performing a 70% partial hepatectomy (PH). After PH, Brg1 was significantly upregulated in wildtype mice. Mice with hepatocyte-specific Brg1 gene knockout showed a significantly lower liver to body weight ratio 48 h post-PH concomitant with a lower hepatocellular proliferation rate compared to wildtype mice. RNA sequencing demonstrated that Brg1 controlled hepatocyte proliferation through the regulation of the p53 pathway and several cell cycle genes. The data of this study reveal a crucial role of Brg1 for liver regeneration by promoting hepatocellular proliferation through modulation of cell cycle genes and, thus, identify Brg1 as potential target for therapeutic approaches.

The compatibilization efficiency of nanoparticles (NPs) towards immiscible polymer blends highly depends on the structural details of NPs. Here, we synthesized three kinds of fluorescently labeled silica NPs with different surface chemistries and roughnesses by using the sol-gel and electrostatic adsorption methods. The efficiencies of NPs in stabilizing immiscible polyisobutylene/polyethylene oxide (10/90) blends under slow shear flow were evaluated in-situ by using the flow-confocal laser scanning microscopy. It was found that the surface chemistry and concentration of NPs determined whether the NP-laden blends get refined or coarsened while the particle roughness further regulates the magnitude of the change in the phase size. Hydrophobic NPs with nanoscale roughness demonstrated the highest stabilization efficiency owing to better dispersion at the blend interface. Therefore, surface roughness is a promising parameter in rationally designing NP-based compatibilizers for polymer blends.

A novel BiCo-based bimetal coordination polymer (BiCo-MCP) with a molecular formula Bi2Co2C42H36N6O33 was synthesized by a mild hydrothermal method. BiCo-MCP was characterized via single crystal X-ray diffraction, SEM and XRD. BiCo-MCP is crystallized in a two-dimensional structure. The energy gap of BiCo-MCP is ~1.65 eV, which indicates that this material can absorb light both in visible and UV regions. This work is the first report on photocatalytic degradation of pesticide by a bismuth-containing bimetallic coordination polymer. The multiplication effect of pH and H2O2 together with BiCo-MCP on the degradation of imidacloprid pesticide wastewater showed that the catalyst system with 1

Streptococcus mutans is considered the primary etiological agent of human dental caries. Glucosyltransferases (Gtfs) from S. mutans play important roles in the formation of biofilm matrix and the development of cariogenic oral biofilm. Therefore, Gtfs are considered an important target to prevent the development of dental caries. However, the role of transcription factors in regulating gtf expression is not yet clear. Here, we identify a MarR (multiple antibiotic resistance regulator) family transcription factor named EpsR (exopolysaccharide synthesis regulator), which negatively regulates gtfB expression and exopolysaccharide (EPS) production in S. mutans. The epsR in-frame deletion strain grew slowly, aggregated more easily in the presence of dextran, and displayed different colony morphology and biofilm structure. Notably, epsR deletion resulted in altered 3-dimensional biofilm architecture, increased water-insoluble EPS production, and upregulated GtfB protein content and activity. In addition, global gene expression profiling revealed differences in the expression levels of 69 genes in which gtfB was markedly upregulated. The conserved DNA motif for EpsR binding was determined by electrophoretic mobility shift assay and DNase I footprinting assays. Moreover, analysis of β-galactosidase activity suggested that EpsR acted as a repressor and inhibited gtfB expression. Taken together, our findings indicate that EpsR is an important transcription factor that regulates gtfB expression and EPS production in S. mutans. These results add new aspects to the complexity of regulating the expression of genes involved in the cariogenicity of S. mutans, which might lead to novel strategies to prevent the formation of cariogenic biofilm that may favor diseases.

Super-resolution fluorescence microscopy has emerged as a powerful tool for studying mitochondrial dynamics in living cells. However, the lack of photostable and chemstable probe makes long-term super-resolution imaging of mitochondria still a challenging work. Herein, we reported a 4-azetidinyl-naphthliamide derived SNAP-tag probe AN-BG exhibiting excellent fluorogenicity and photostability for long-term super-resolution imaging of mitochondrial dynamics. The azetidinyl group and naphthalimide fluorophore are in a flat conformation which can effectively suppress twisted intramolecular charge transfer and then effectively improve the brightness and photostability. This planarized molecular structure is conducive to the formation of fluorescence-quenched J-aggregates, and the protein labeling process will depolymerize the probes and restore fluorescence. Fluorescent labeling mitochondrial inner membrane proteins via SNAP tags overcomes the shortcomings that variations in mitochondrial inner membrane potential will release probes attached to mitochondria by electrostatic interactions. Therefore, AN-BG realized the stable labeling of mitochondria and the long-term imaging of mitochondrial dynamics under super-resolution microscopy.

Reduced graphene oxide (rGO)/ZnO heterostructure was prepared via electrochemical deposition directly on Hummers method derived rGO membranes and the corresponding diodes had been fabricated. Rectifying I–V curve was obtained by modifying the functional groups on the surface of rGO. Further investigation for GO based transistors showed that the conductivity of rGO could vary from n-type to p-type under different annealing conditions. Based on Lerf-Klinowski model and X-Ray photoelectron spectroscopy, it was found that the C-sp 2 , hydroxyl and epoxy in rGO would be responsible for the change of electrical properties. It was also concluded that reasonable p-type conductivity of rGO for obtaining rectifying rGO/ZnO heterostructure occurred while the percentage of C-sp 2 content was about 54% with the C-sp 2 /(OH + C-O-C) ratio around 1.6.

Zinc (Zn)-containing materials have osteogenic and antibacterial activities while bioactive glass nanoparticles (BGN) show bone-bonding ability, as well as osteoconductive and osteoinductive properties. Zn-containing BGN are therefore considered to be promising materials for various biomedical applications, particularly in bone regeneration. In this study, we report a convenient method to prepare Zn-containing BGN by coating ZnO quantum dots (QDs) on BGN via electrostatic interactions. The synthesized ZnO–BGN nanocomposite particles are spherical and highly dispersed, and exhibit a unique fluorescence behavior under UV excitation, emitting three wavelengths in the violet, blue and green range. ZnO–BGN showed apatite-forming ability upon immersion in simulated body fluid, but their apatite formation was delayed compared to BGN. Interestingly, ZnO–BGN showed a rapid release of Zn ions at pH 4 but a far slower release at pH 7.4. ZnO–BGN also exhibited antibacterial effects on both Gram-positive and Gram-negative bacteria at the concentrations of 1, 0.1, and 0.01 mg mL−1. Higher concentrations could lead to stronger antibacterial effects. The LDH and live/dead assays indicated that ZnO–BGN had no significant cytotoxicity towards human mesenchymal stem cells (hMSC) at concentration of 0.1 and 0.01 mg mL−1, but ZnO–BGN inhibited the relative proliferation of hMSC compared to BGN and the control according to the MTT assay. Notably ZnO–BGN improved the osteogenic differentiation of hMSC as indicated by the determination of the alkaline phosphatase activity. In conclusion, coating quantum dots on BGN is a promising strategy to produce Zn-containing BGN. The synthesized ZnO–BGN are potential materials for bone regeneration, considering their apatite-forming ability, unique ion-release behavior, effective antibacterial activity, non-cytotoxicity, and osteogenic potential.

The photoluminescence of graphene oxide quantum dots (GOQDs) is known to be quenched by metal ions. In this paper, this quenching effect has been found to be strengthened with the increase of environmental pH, which would introduce hydroxyl group for GOQDs because other kinds of functional groups have the trend to evolve towards hydroxyl with increasing pH. Thus, a pH-dependent fluorescent quenching of GOQDs can be obtained, which might further guide the metal ion detection of GOQDs in a practical application.

Discarded solution of graphene oxide's fabrication via Hummers' method was recycled for the synthesis of TiO2 photocatalyst on carbon fiber cloth. The composite photocatalyst exhibited a high surface area of 497 m2 g−1, and a production rate of 83.88 μmol g−1 h−1 in the photocatalytic CO2 reduction to CH4. The acidity, oxidability and complicated cation specimen of the discarded solution, which was meant to be hazardous to the environment, have been made full use of to facilitate such highly dense, 1D and anatase TiO2 nanorods on carbon fiber.

Peroxisome Proliferator-Activated Receptor gamma (PPARγ) is a nuclear receptor demonstrated to play an important role in various biological processes. The aim of this study was to determine the effect of PPARγ on liver regeneration upon partial hepatectomy (PH) in mice. Mice were subjected to two-thirds PH. Before surgery, mice were either treated with the PPARγ agonist rosiglitazone, the PPARγ antagonist GW9662 alone, or with the c-met inhibitor SGX523. Liver-to-body-weight ratio, lab values, and proliferation markers were assessed. Components of the PPARγ-specific signaling pathway were identified by western blot and qRT-PCR. Our results show that liver regeneration is being inhibited by rosiglitazone and accelerated by GW9662. Inhibition of c-Met by SGX523 treatment abrogates GW9662-induced liver regeneration and hepatocyte proliferation. Hepatocyte growth factor (HGF) protein levels were significantly downregulated after rosiglitazone treatment. Activation of HGF/c-Met pathways by phosphorylation of c-Met and ERK1/2 were inhibited in rosiglitazone-treated mice. In turn, blocking phosphorylation of c-Met significantly abrogated the augmented effect of GW9662 on liver regeneration. Our data support the concept that PPARγ abrogates liver growth and hepatocellular proliferation by inhibition of the HGF/c-Met/ERK1/2 pathways. These pathways may represent potential targets in response to liver disease and could impact on the development of molecular therapies.

An effective method for the ultrasound-assisted extraction of indigo and indirubin from Isatis indigotica Fort. was established and their antioxidant activities were investigated. Response surface methodology based on a three-level, four-factor Box–Behnken design was used to optimize the extraction conditions. Analysis of variance showed that the quadratic model was significant for the extraction of indigo and indirubin (112.72% ± 1.65% and 116.42% ± 1.27%, respectively) under the optimal conditions (methanol concentration, 80%; extraction time, 25 min; ratio of solid to liquid, 1:34 g/mL; and extraction temperature, 41 °C) and was in good agreement with the predicted value. Moreover, evaluation of the antioxidant activities suggested that indigo and indirubin presented better scavenging effects on 1,1-diphenyl-2-picrylhydrazyl free radical and superoxide radical than the extract and the extract revealed certain antioxidant activities in hydroxyl radical scavenging and reducing power, and indigo and indirubin could be used as natural antioxidants in the food or medicine industry.

Objectives. To investigate the potential association of a set of serum cytokines with the severity of coronary artery disease (CAD). Methods. A total of 201 patients who underwent coronary angiography for chest discomfort were enrolled. The concentrations of serum IFN-γ, TNF-α, IL-2, IL-4, IL-6, IL-10, IL-9, and IL-17 were determined by xMAP multiplex technology. The CAD severity was assessed by Gensini score (GS). Results. The serum levels of TNF-α, IL-6, IL-9, IL-10, and IL-17 were significantly higher in high GS group (GS ≥ 38.5) than those in low GS group (GS < 38.5). Positive correlations were also found between these cytokines and the severity of CAD. After adjustment for other associated factors, three serum cytokines (IL-6, IL-9, and IL-17) and two clinical risk factors (creatinine and LDL-C) were identified as the independent predictors of increased severity of CAD. ROC curve analysis revealed that the logistic regression risk prediction model had a good performance on predicting CAD severity. Conclusions. Combinatorial analysis of serum cytokines (IL-6, IL-9, and IL-17) with clinical risk factors (creatinine and LDL-C) may contribute to the evaluation of the severity of CAD and may help guide the risk stratification of angina patients, especially in primary health facilities and in the catheter lab resource-limited settings.

The ZnCl2 activated electrospun carbon nanofiber (Zn-AECNF) was fabricated by the electrospinning of polyacrylonitrile (PAN) nanofiber, followed by the preoxidation, carbonization and ZnCl2 post-treatment. The activated carbon nanofiber was characterized by scanning electron microscopy (SEM), contact angle, X-ray photoelectron spectroscopy, infrared spectroscopy and nitrogen adsorption. The carbon nanofiber obtained with ZnCl2 activation exhibits good flexibility, high hydrophilicity, and improved specific surface area. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) demonstrated the enhanced capacitance and improved electric conductivity due to the treatment of ZnCl2. The Zn-AECNF was used for capacitive desalination successfully. With the higher ZnCl2 concentration used for carbon fiber impregnation, the specific surface area of the obtained carbon fiber was increased, and the desalination performance was enhanced accordingly. The salt adsorption of 10.52 mg/g was achieved when 60% ZnCl2 solution was used. The Zn-AECNF electrodes offer high potential for use in capacitive desalination technology.

Oxidative torrefaction is a method to reduce the operating cost of upgrading biomass. To understand the potential of oxidative torrefaction and its impact on the internal structure of biomass, non-oxidative and oxidative torrefaction of two fibrous biomass materials (oil palm fiber and coconut fiber) and two ligneous ones (eucalyptus and Cryptomeria japonica) at 300 °C for 1 h are studied and compared with each other. Scanning electron microscope (SEM) observations are also performed to explore the impact of torrefaction atmosphere on the lignocellulosic structure of biomass. The results indicate that the fibrous biomass is more sensitive to O2 concentration than the ligneous biomass. In oxidative torrefaction, an increase in O2 concentration decreases the solid yield. The energy yield is linearly proportional to the solid yield, which is opposite to the behavior of non-oxidative torrefaction. The performance of non-oxidative torrefaction is better than that of oxidative torrefaction. As a whole, ligneous biomass can be torrefied in oxidative environments at lower O2 concentrations, whereas fibrous biomass is more suitable for non-oxidative torrefaction.

Fluorescent probes based on quantum dots (QDs) are emerging as ideal tools for sensing and imaging in biological applications owing to their great advantages such as high sensitivity and unique optical properties. Using QDs as potential effective tools for tumor optical imaging would allow early diagnosis, monitoring of tumor progression and treatment efficiency. We prepared a novel folate receptor-targeted, PEG-modified fluorescent probe based on silica-coated CdTe QDs. In the study, the hydrophilic thioglycolic acid stabilized CdTe QDs were directly synthesized in the water phase; the water-in-oil (W/O) reverse microemulsion method was applied to prepare the highly fluorescent amino-functionalized core–shell CdTe@SiO2 particles; subsequently, polyethylene glycol (PEG) and folate molecules were successfully bioconjugated with the CdTe@SiO2 particles through the amino groups. The as-prepared particles were characterized by UV-Vis absorption, fluorescence measurements, particle size, zeta potential and high-resolution transmission electron microscopy (HR-TEM). The bioimaging efficiency and specificity of the prepared fluorescent probes were further evaluated on KB cells. Results indicate that the silica film encapsulated and PEGylated CdTe QDs can significantly reduce the cytotoxicity of CdTe QDs. In conclusion, folate receptor-targeted, PEG-modified and silica-coated CdTe quantum dot fluorescent probes are highly promising for tumor imaging in the near future.

Background Activation of the immune system in terms of subseptic conditions during liver regeneration is of paramount clinical importance. However, little is known about molecular mechanisms and their mediators that control hepatocyte proliferation. We sought to determine the functional role of immune cells, especially NKT cells, in response to partial hepatectomy (PH), and to uncover the impact of the integrin lymphocyte function-associated antigen-1 (LFA-1) on liver regeneration in a subseptic setting. Methods Wild-type (WT) and LFA-1-/- mice underwent a 2/3 PH and low-dose lipopolysaccharid (LPS) application. Hepatocyte proliferation, immune cell infiltration, and cytokine profile in the liver parenchyma were determined. Results Low-dose LPS application after PH results in a significant delay of liver regeneration between 48h and 72h, which is associated with a reduced number of CD3+ cells within the regenerating liver. In absence of LFA-1, an impaired regenerative capacity was observed under low-dose LPS application. Analysis of different leukocyte subpopulations showed less CD3+NK1.1+ NKT cells in the liver parenchyma of LFA-1-/- mice after PH and LPS application compared to WT controls, while CD3-NK1.1+ NK cells markedly increased. Concordantly with this observation, lower levels of NKT cell related cytokines IL-12 and IL-23 were expressed in the regenerating liver of LFA-1-/- mice, while the expression of NK cell-associated CCL5 and IL-10 was increased compared to WT mice. Conclusion A subseptic situation negatively alters hepatocyte proliferation. Within this scenario, we suggest an important impact of NKT cells and postulate a critical function for LFA-1 during processes of liver regeneration.

The properties of biomass can be improved via torrefaction, and torrefied wood is a fuel with the potential to partially replace coal. In this study, raw Cryptomeria japonica (WRaw) is torrefied at 250 (TW250) and 300 °C (TW300) for 1 h, and then mixed with an anthracite coal to undergo co-pyrolysis. A thermogravimetric analyzer is used to examine the co-pyrolysis characteristics of fuel blends and five different biomass blending ratios (BBRs) of 100, 75, 50, 25, and 0 wt.% are taken into consideration. When WRaw, TW250, and the coal are tested, the pyrolysis is characterized by a three-stage reaction, whereas four-stage thermal degradation is found for TW300 and fuel blends. The predictions from the linear superposition of the thermal decomposition of individual fuels fit the experimental data of the fuel blends, suggesting that the interaction or synergistic effect of co-pyrolysis between the raw/torrefied C. japonica and the coal is slight. The co-pyrolysis kinetics of the fuel blends is also analyzed. The variation of chemical kinetics with decreasing BBR in the second stage is different from that in the third stage. That is, an increase in BBR leads to an increase in the activation energy in the second stage, whereas it causes a decrease in the third stage. This is attributed to that the reactivities of cellulose and lignin in biomass are different from that of coal in the two stages.

PurposeThe purpose of this paper is to report a simple, room temperature approach to assemble dense, vertically aligned single‐walled carbon nanotubes (SWNTs) between a chip and its substrate acting as a kind of thermal interface material by virtue of better mechanical and thermal properties.Design/methodology/approachTwo silicon chips, with shallow trenches about 2 μm deep on the surface, were pressed together face to face with the trench direction perpendicular to each other. SWNT aqueous solution was driven into the gap between the two chips by capillary force. Later, the sample was baked to remove the moisture completely.FindingsSWNTs beams were found to be assembled in the gap and have their two ends bonding with the interface of the two chips, respectively. The shear strength of the two chips was measured, and the thermal conductivity of the stacked chip‐SWNTs‐chip was tested using a laser flash method. In result, shear strength up to about 100 kPa, and an average thermal conductivity of 19.3 W·m−1·K−1 were demonstrated.Originality/valueThe paper proposes an approach to grown dense SWNT array bridging a chip and its substrate, and these SWNTs have potential capability to provide mechanical strength and higher thermal conductance instead of commercial thermal interface materials.

Three agricultural wastes, consisting of coffee residue, sawdust and rice husk, undergoing torrefaction are investigated to evaluate the potential of biomass as solid fuel. Two different torrefaction temperatures (240 and 270 °C) and durations (0.5 and 1 h) are considered in the study, and the properties and structures of the raw and torrefied wastes are extensively investigated by means of proximate, elemental, fiber, calorific, thermogravimetric, SEM and FTIR analyses. A high-volatile bituminous coal and a low-volatile one are also regarded for comparison. By virtue of more hemicellulose contained in the coffee residue, it is the most active biomass to torrefaction and its higher heating value (HHV) is improved up to 38%. The empirical atomic formula of the raw wastes is expressed by CH1.54–1.76O0.65–0.89 and it changes to CH1.02–1.57O0.26–0.64 after undergoing torrefaction. The torrefied biomasses approach high-volatile coal when the torrefaction temperature and duration increase. From fuel point of view, the improved properties and changed molecular structure are conducive to the applications of biomass in industrial furnaces such as boilers and blast furnaces.

BACKGROUND AND PURPOSE Spinal reactive oxygen species (ROS) are critically involved in chronic pain. d-Amino acid oxidase (DAAO) oxidizes d-amino acids such as d-serine to form the byproduct hydrogen peroxide without producing other ROS. DAAO inhibitors are specifically analgesic in tonic pain, neuropathic pain and cancer pain. This study examined the role of spinal hydrogen peroxide in pain and the mechanism of the analgesic effects of DAAO inhibitors. EXPERIMENTAL APPROACH Formalin-induced pain behaviours and spinal hydrogen peroxide levels were measured in rodents. KEY RESULTS Formalin injected into the paw increased spinal hydrogen peroxide synchronously with enhanced tonic pain; both were effectively prevented by i.t. fluorocitrate, a selective astrocyte metabolic inhibitor. Given systemically, the potent DAAO inhibitor CBIO (5-chloro-benzo[d]isoxazol-3-ol) blocked spinal DAAO enzymatic activity and specifically prevented formalin-induced tonic pain in a dose-dependent manner. Although CBIO maximally inhibited tonic pain by 62%, it completely prevented the increase in spinal hydrogen peroxide. I.t. catalase, an enzyme specific for decomposition of hydrogen peroxide, completely depleted spinal hydrogen peroxide and prevented formalin-induced tonic pain by 65%. Given systemically, the ROS scavenger PBN (phenyl-N-tert-butylnitrone) also inhibited formalin-induced tonic pain and increase in spinal hydrogen peroxide. Formalin-induced tonic pain was potentiated by i.t. exogenous hydrogen peroxide. CBIO did not increase spinal d-serine level, and i.t. d-serine did not alter either formalin-induced tonic pain or CBIO's analgesic effect. CONCLUSIONS AND IMPLICATIONS Spinal hydrogen peroxide is specifically and largely responsible for formalin-induced pain, and DAAO inhibitors produce analgesia by blocking spinal hydrogen peroxide production rather than interacting with spinal d-serine.

The improvement on physical and chemical properties of pulverized biomass from torrefaction is investigated to evaluate the potential of biomass as solid fuel used in boilers and blast furnaces. Three biomasses of bamboo, banyan and willow are considered. The results indicate that when the torrefaction temperature is relatively low such as 230 and 260 °C, the weight loss of biomass depends significantly on the temperature, as a result of consumptions of hemicellulose and cellulose. However, once the torrefaction temperature is as high as 290 °C, the weight losses of various biomass materials tend to become uniform. The decreased O/C ratio in biomass from torrefaction can be explained by intensified lignin content in that the O/C ratio in lignin is low compared to that in hemicellulose and cellulose. Furthermore, the enriched element C in torrefied biomass results in an increase in the calorific value of the torrefied materials. However, the enlarged higher heating value (HHV) of biomass from torrefaction cannot keep up with the weight loss; this leads to the decrease in total energy of biomass as the torrefaction temperature rises. The conducted correlation in predicting the HHV of raw biomass can also be utilized for torrefied biomass. The raw pulverized biomasses are characterized by agglomeration in the regime of smaller particle size. Once the biomasses undergo torrefaction, the dispersion of powder is improved, thereby facilitating the injection of biomass powder. This enhances the applications of pulverized biomass in boilers and blast furnaces.

Natural Science Foundation of China (NSFC)[20973144, 21033007, 21021002]; Special Funds for Major State Basic Research Project of China[2007CB935603]

We report an electrochemically assisted mechanically controllable break junction (EC-MCBJ) approach to investigating single molecule conductance. Electrode pairs connected with a gold nanobridge were fabricated by electrochemical deposition and then mounted on a homebuilt MCBJ platform. A large number of Au- molecule-Au junctions were produced sequentially by repeated breaking and reconnecting of the gold nanobridge. In order to measure their single molecule conductance, statistical conductance histograms were generated for benzene-1,4-dithiol (BDT) and 4,4′-bipyridine (BPY). The values extracted from these histograms were found to be in the same range as values previously reported in the literature. Our method is distinct from the ones used to acquire these previously reported literature values, however, in that it is faster, simpler, more cost-effective, and changing the electrode material is more convenient. Open image in new window

The purpose of this study is to investigate the torrefaction behavior of woody biomass (Lauan) blocks and its influence on the properties of the wood. Three different torrefaction temperatures of 220, 250 and 280 °C, corresponding to light, mild and severe torrefactions, and four torrefaction times of 0.5, 1, 1.5 and 2 h were considered. After analyzing the torrefied woods, it was found that the torrefaction temperature of 280 °C was able to increase the calorific value of the wood up to 40%. However, over 50% of weight was lost from the wood. The grindability of the torrefied wood could be improved in a significant way if the torrefaction temperature was as high as 250 °C and the torrefaction time longer than 1 h. Therefore, the torrefaction temperature of 250 °C along with the torrefaction time longer than 1 h was the recommended operation to intensify the heating value and grindability as well as to avoid too much mass loss of the wood. This study also suggested that over 50% of the reacted wood was converted into condensed liquid. The main components in the liquid were monoaromatics; little amount of heterocyclic hydrocarbons were also obtained from the torrefactions, especially at the torrefaction temperature of 280 °C.

Wendian Zhang,1 Fangqi Peng,1 Taotao Zhou,1 Yifei Huang,2 Li Zhang,3 Peng Ye,4 Miao Lu,1 Guang Yang,5 Yongkang Gai,1 Tan Yang,1 Xiang Ma,1 Guangya Xiang1 1School of Pharmacy, Tongji Medical College, 2Department of Pharmacy, 3Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 4Department of Pharmacy, Wuhan University, Renmin Hospital, 5School of Medicine, Jianghan University, Wuhan, People’s Republic of China Abstract: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death. Gene therapy was established as a new strategy for treating HCC. To explore the potential delivery system to support the gene therapy of HCC, negatively charged liposomal delivery system was used to deliver miR-221 antisense oligonucleotide (anti-miR-221) to the transferrin (Tf) receptor over expressed HepG2 cells. The liposome exhibited a mean particle size of 122.5nm, zeta potential of -15.74mV, anti-miR-221 encapsulation efficiency of 70%, and excellent colloidal stability at 4°C. Anti-miR-221-encapsulated Tf-targeted liposome demonstrated a 15-fold higher delivery efficiency compared to nontargeted liposome in HepG2 cells in vitro. Anti-miR-221 Tf-targeted liposome effectively delivered anti-miR-221 to HepG2 cells, upregulated miR-221 target genes PTEN, P27kip1, and TIMP3, and exhibited greater silencing efficiency over nontargeted anti-miR-221 liposome. After intravenous injection into HepG2 tumor-bearing xenografted mice with Cy3-labeled anti-miR-221 Tf-targeted liposome, Cy3-anti-miR-221 was successfully delivered to the tumor site and increased the expressions of PTEN, P27kip1, and TIMP3. Our results demonstrate that the Tf-targeted negatively charged liposome could be a potential therapeutic modality in the gene therapy of human HCC. Keywords: transferrin, gene, HCC, target delivery system, anionic liposome&nbsp