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A novel double-stranded RNA virus was isolated and identified from Beauveria bassiana Vuillemin, derived from the muscardine cadaver of an Ostrinia furnacalis larva in China. The virus contains six dsRNAs, and each viral dsRNA contains only one open reading frame (ORF). As in other polymycoviruses, dsRNA1 encodes an RNA-dependent RNA polymerase (RdRp), dsRNA3 encodes a methyltransferase (MTR), and dsRNA4 encodes a proline-alanine-serine-rich protein. A BLASTp search revealed that the viral RdRp domain showed 79.43%, 79.04%, and 59.05% sequence identity to Beauveria bassiana polymycovirus 2 and 3 (BbPmV-2, BbPmV-3) and Magnaporthe oryzae polymycovirus 1 (MoPmV-1), respectively. Phylogenetic analysis based on RdRp sequences showed that the phylogenetically closest relatives of this virus are BbPmV-2, BbPmV-3, and MoPmV-1. This virus, along with previously ill-defined polymycoviruses (BbPmV-2 and BbPmV-3), appears to belong to an as-yet-unestablished species. The findings further suggest that the virus is a new member of the genus Polymycovirus within the family Polymycoviridae, and we have named it "Beauveria bassiana polymycovirus 4" (BbPmV-4). However, the sixth dsRNA is a defective RNA with the same sequence as that of dsRNA4 except for a deletion of 312 bp from nt 185 to nt 496, but it still contains a complete ORF. To our knowledge, this is the first report of the existence of a defective RNA in a polymycovirus.

Purpose With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure to a harsh environment of high-pressure hydrogen at medium temperature in practical application would still induce severe hydrogen uptake and eventually damage the mechanical properties of the steel. The study aims to evaluate the HE resistance of the steel under different tensile strain rates after hydrogen charging and analyze the hydrogen effect from atomic level. Design/methodology/approach This research studied the HE properties of 12Cr2Mo1R(H) steel by slow strain rate tests. Meanwhile, the effect of hydrogen on the structures and the mechanical properties of the simplified models of the steel was also investigated by first-principle calculations. Findings Experimental results showed that after hydrogen pre-charging in this work, hydrogen had little effect on the microstructure of the steel. The elongations and reduction of cross-sectional area of the samples reduced a lot, by contrast, the yield and tensile strengths changed slightly. The 12Cr2Mo1R(H) steel was not very susceptible to HE with a maximum embrittlement index of about 20.00%. First principles calculation results showed that after H dissolution, lattice distortion occurred and interstitial H atoms would preferentially occupy the tetrahedral interstitial site in bcc-Fe crystal and increase the stability of the supercells. With the increase of H atoms added into the simplified model, the steel still possessed a good ductility and toughness at a low hydrogen concentration, while the material would become brittle as the concentration of hydrogen continued to increase. Originality/value These finds can provide valuable information for subsequent HE studies on this steel.

Isothermal amplification, such as hybridization chain reaction (HCR), is a simple and reliable method for detecting signal amplification. However, the hairpin in HCR will not fully participate in the reaction. And after the hairpin is opened, the distance between the fluorophore and the quencher does not change much. Therefore, the signal magnification is limited. Here, we designed a new isothermal amplification method named hybridization assemble nicked displacement amplification (HANDA), combining HCR and strand displacement amplification (SDA) ingeniously. HANDA first triggers HCR through the target sequence to form long double-strand DNA (dsDNA) with gaps. Then SDA is performed from the gap to obtain a large amount of single-stranded DNA (ssDNA), so as to achieve the purpose of double signal amplification. The base sequence of DNA hairpin had also been optimized. The best sequence design rule was found and had universal applicability. We have demonstrated that HANDA combined with DNA barcodes can be used for trace detection of ricin. This new isothermal amplification method provides an effective and universal platform for the trace detection of various toxic substances.

Starch is an inexpensive feed ingredient that has been widely used in fish feed. However, starch utilization by carnivorous fish is limited and excess starch is detrimental to the health of the organism. High starch diets often lead to liver damage, but the effects on the intestine are often overlooked. Therefore, in this study, two isonitrogenous and isolipidic semi-pure diets (NC: 0% α-starch, HC: 22% α-starch) were formulated and fed to largemouth bass (Micropterus salmoides) for 45 days. The effects of the high starch diet on the intestine of largemouth bass were comprehensively investigated by intestinal microbiota, histopathology, ultrastructural pathology, and enzymology analyses. Feeding the HC diet did not affect the growth of largemouth bass during the experimental period. However, the high starch diet led to a reduction in the diversity and abundance of intestinal microbiota in largemouth bass, with a significant increase in the abundance of harmful bacteria (Aeromonas) and a decrease in the abundance of beneficial bacteria (Clostridium, Lactobacillus, and Bifidobacterium). Feeding the HC diet caused the development of enteritis, with goblet cell hyperplasia, epithelial necrosis and detachment and inflammatory cell infiltration, and leading to enlarged apical openings and mitochondrial damage in goblet cells. Long-term feeding of the HC diet inhibited intestinal α-amylase activity. changes in the intestinal microbiota, such as an increase in Aeromonas and a decrease in Clostridium, Lactobacillus, and Bifidobacterium, may be closely related to the development of enteritis. Therefore, adding these beneficial bacteria as probiotics may be an effective way to prevent damage to the intestine of largemouth bass from a high carbohydrate diet. Our results suggest reducing the amount of starch added to the largemouth bass diets. This study provides a reference for protecting the largemouth bass gut during modern intensive culture.

A derivatization method to determine the sulfur dioxide content in food was established. Under weakly acidic conditions, fluorescent 2H-isoindole-1-sulfonate was synthesized by a derivatization reaction using an ammonium salt and o-phthalaldehyde as the derivative reagent. High-performance liquid chromatography and a high-sensitivity fluorescence detector were used for detection, in which a fluorescence spectrophotometer was used to determine the maximum excitation wavelength and emission wavelength of2H-isoindole-1-sulfonate. When the excitation wavelength was 323 nm and the emission wavelength was 386 nm, the linear range of fluorescence intensity of the sulfur dioxide standard was 0–10 μg/mL, and the correlation coefficient was 0.996. The standard recoveries of six kinds of food were approximately 80–110%, the RSD was 0.2–2.89, the detection limit was 0.2 mg/kg, and the quantitative limit was 0.7 mg/kg. The results of this research indicate that this method is suitable for determining sulfur dioxide in food.

Metal ionic capacitors (MICs) are a new type of hybrid electrochemical energy storage (EES) devices that integrate the advantages of high-power output in supercapacitors and high energy density in batteries. These materials show potential to be commercialized, but their practical application is still limited due to the imbalance of kinetics and capacity between the electrodes, the slow ion/electron diffusion rate and the poor structural stability of the electrodes. 3D graphene-based materials with unique structure and appealing properties have recently received attentions for application in MICs due to their remarkable improvement from charge storage capacity to reaction kinetics. In this article, we reviewed the research progress of 3D graphene-based materials in lithium-ion capacitors (LICs) and sodium ion capacitors (SICs). Firstly, the energy storage principle and development requirements of LICs and SICs are introduced. The fabrication of 3D graphene materials is then summarized. The key advantages and important roles of 3D graphene-based materials in the construction of LICs and SICs are discussed. Finally, the challenges and prospects regarding the application of 3D graphene-based materials in high-performance LICs and SICs are presented.

Graphene oxide (GO), a derivative of graphene, has attracted widespread attention due to its easy functionalization and excellent water solubility. Therefore, a method for efficiently producing GO shoule be developed. Although the traditional chemical oxidation method is broadly employed for GO synthesis, it entails problems, such as long time-consuming, explosive danger and easy to pollute the environmental. Recent research on using electrochemical methods for GO synthesis has achieved a breakthrough, that is, the realization of pollution-free, safe and efficient large-scale preparation of high-quality GO within a few hours. This article introduces the principle of electrochemical GO synthesis and summarizes the progress of research on GO preparation via two-electrode, three-electrode and electrolyte exfoliation with focalize on product quality and quantity. The challenges in high-quality electrochemical GO production and future research directions are also presented.

2-Hydroxyethylammonium acetate ionic liquid was found to be an excellent catalyst for the one-pot synthesis of 1,4-dihydropyridine derivatives via Hantzsch reaction of ethyl acetoacetate or acetoacetanilide, ammonium acetate, and various aromatic aldehydes. The combinatorial syntheses were achieved for the first time using 2-hydroxyethylammonium acetate ionic liquid as a homogeneous catalyst. The catalyst was active for the Hantzsch reaction in alcohol at reflux. The products were isolated in good yields (78–93 %). The resulting substituted dihydropyridines were characterized and confirmed by1H NMR spectral data. The catalyst offers simple means for recovery and the isolated catalyst was reused for three rounds for the synthesis without significant loss of catalytic activity. For all the other reactions carried out with the recycled catalyst, results were similar to that with the fresh catalyst.

Silica-supported sulfonic acid–functional ionic liquid (Si-[SbSipim][PF6]) was found to be an effective catalyst for the synthesis of 3,4-dihydropyrimidine-2-(1H)-ones via a one-pot, three-component Biginelli reaction. The catalyst could be easily separated and reused six times without noticeable reduction inactivity. The process was simple and proceeded in excellent yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

2-Hydroxyethylammonium acetate ionic liquid was found to be an excellent catalyst for the one-pot synthesis of 1,4-dihydropyridine derivatives via Hantzsch reaction of ethyl acetoacetate or acetoacetanilide, ammonium acetate, and various aromatic aldehydes. The combinatorial syntheses were achieved for the first time using 2-hydroxyethylammonium acetate ionic liquid as a homogeneous catalyst. The catalyst was active for the Hantzsch reaction in alcohol at reflux. The products were isolated in good yields (78–93 %). The resulting substituted dihydropyridines were characterized and confirmed by1H NMR spectral data. The catalyst offers simple means for recovery and the isolated catalyst was reused for three rounds for the synthesis without significant loss of catalytic activity. For all the other reactions carried out with the recycled catalyst, results were similar to that with the fresh catalyst.

We investigated the Ni/ZrO2 catalyst performance of YBa2Cu3O7-x (YBCO) membrane reactor in the process of partial oxidation of methane (POM) to syngas by TG. The activity of the catalyst effected not only on the methane conversion but also CO selectivity. The effect of temperature on CO selectivity was little and could be neglected.The change of CH4 conversion along time was caused by the deactivation of catalyst or/and the decay of membrane reactor. The loss of catalysts increase with temperature accoding to the carves of TG .

A novel method of cell affinity screening (CAS), cell affinity capture coupled with LC-MS analysis, was developed for screening the bioactive compounds related to cardiovascular diseases from the natural product libraries. One of the major characteristics lies in its function in affinity-capturing and separating the bioactive components from the natural product libraries in vitro. Another characteristic is its use in analyzing and identifying the target compounds, by employing high-performance liquid chromatography and mass spectrometry. CAS was used for screening the bioactive components from the alkaloid extract derived from Aconitum szechenyianum Gay. Of the five components found to be bound to the oxidative-damaged endothelial cells, the two compounds identified, mesaconitine and aconitine, were recognized in the literature as being related to cardiovascular diseases. Copyright © 2008 John Wiley & Sons, Ltd.

Condensation of aromatic aldehydes with cyclopentanone and cyclohexanone using amino-functionalized ionic liquid, 1-aminoethyl-3-methyl tetrafluoroborate as solvent and catalyst was successfully performed for preparation of α,α′-bis(substituted benzylidene)cycloalkanones. The catalyst can be recovered and reused for at least three times without apparently lose of activity. The process is simple, environmentally benign and proceeds in excellent yields.

Transient receptor potential (TRP) channels in the spinal dorsal horn lamina II (substantia gelatinosa; SG), which are involved in the modulation of nociceptive transmission, have not yet been fully examined in property. Activation of the TRP channels by various plant-derived chemicals results in an increase in the spontaneous release of l -glutamate onto the SG neurons. We examined the effects of a monoterpene ketone (−)-carvone (contained in spearmint) and its stereoisomer (+)-carvone (in caraway) on glutamatergic spontaneous excitatory transmission in SG neurons of adult rat spinal cord slices by using the whole-cell patch-clamp technique. (−)-Carvone and (+)-carvone increased the frequency of spontaneous excitatory postsynaptic current (sEPSC) in a reversible and concentration-dependent manner with a small increase in its amplitude. Half-maximal effective concentrations of (−)-carvone and (+)-carvone in increasing sEPSC frequency were 0.70 mM and 0.72 mM, respectively. The (−)-carvone but not (+)-carvone activity was inhibited by a TRPV1 antagonist capsazepine. On the other hand, the (+)-carvone but not (−)-carvone activity was inhibited by a TRPA1 antagonist HC-030031. These results indicate that (−)-carvone and (+)-carvone activate TRPV1 and TRPA1 channels, respectively, resulting in an increase in spontaneous l -glutamate release onto SG neurons, with almost the same efficacy. Such a difference in TRP activation between the stereoisomers may serve to know the properties of TRP channels in the SG.

It has been demonstrated that the number and differentiating potential of bone marrow mesenchymal stem cells (MSCs) decrease with age. Therefore, the search for alternative sources of MSCs is of significant value. In the present study, MSCs were isolated from umbilical cord blood (UCB) by combining gradient density centrifugation with plastic adherence. Cultured cells were treated with ascorbate acid-2-phosphate, dexamethasone, β-glycerophosphate dexamethasone, insulin, 1-methyl-3-isobutylxamthine, indomethacin, β-mercaptoethanol, butylated hydroxyanisole, FGF-4 and HGF. Differentiating characterization of UCB-derived MSCs were detected by cytochemistry, immunocytochemistry, radioimmunoassay, RT-PCR and urea assay. The results showed UCB-derived MSCs could differentiate into osteoblasts, adipocytes and neuron-like cells. When MSCs were cultured with FGF-4 and HGF, approximately 63.6% of cells became small, round and epithelioid on day 28 by morphology. Compared with the control, levels of AFP in the supernatant liquid increased significantly from day 12 and were higher on day 28 (P < 0.01). Albumin increased significantly from day 16 (P < 0.01). Urea was first detected on day 20 (P < 0.01), and continued to increase on day 28 (P < 0.01). Cells first expressed CK-18 on day 16 through immunocytochemistry analysis. RT-PCR analysis showed that differentiated cells could express a number of hepatocyte-specific genes in a time-dependent manner. Glycogen storage was first seen on day 24. Our results suggest that UCB-derived MSCs can differentiate not only into osteoblasts, adipocytes and neuron-like cells, but also into hepatocytes. Human UCB-derived MSCs are a new source of cell types for cell transplantation and therapy.

Silica-supported sulfonic acid–functional ionic liquid (Si-[SbSipim][PF6]) was found to be an effective catalyst for the synthesis of 3,4-dihydropyrimidine-2-(1H)-ones via a one-pot, three-component Biginelli reaction. The catalyst could be easily separated and reused six times without noticeable reduction inactivity. The process was simple and proceeded in excellent yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

To simultaneously determine three components of aconitine, mesaconitine, and hypaconitine in six species of Aconitum genus, an extraction condition for the total alkaloids was specifically optimized and a simple analytical method of reversed-phased highperformance liquid chromatography (HPLC) was developed. The extraction rate of total alkaloids in A. szechenyianum Gay was 98.3% for repeated extracting three times with an acidic alcohol solution (alcohol: pH 3.0 HAc = 85:15, v/v). The chromatography was carried out on a Phenomenex Luna C 18 column by gradient elution with a mobile phase of 0.03 mol/mL ammonium bicarbonate (pH = 9.50) ‐acetonitrile at a flow rate of 1.0 mL/min. The method for all three alkaloids had good linear relationships (r > 0.999) in the concentration range of 1.0‐200.0 µg/mL. The average recoveries were 96.6‐103.1%, and the LOQ and LOD were in the range of 25‐37 ng/mL and 9‐12 ng/mL, respectively. The quantitative results indicated that contents of the three alkaloids varied significantly among crude aconite roots, so quality control of traditional Chinese medicines containing aconite roots should be taken into account.

The methodology of using a silica gel-supported functionalized ionic liquid as a scavenger in the purification of parallel synthesis products was demonstrated. Silica-supported sulfonic acid-functional ionic liquid was synthesized by etherification, aminate, and quaternary aminate from activated silica gel and 3-chloropropyl trimethoxysilane, imidazole, and 1,4-butanesultone, which was followed by acidification using trifluoromethanesulfonic acid and anion exchange with potassium hexafluorophosphate. A conventional ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate was then used to coat the surface of the silica gel. The silica-supported functionalized ionic liquid was used as a scavenger in the removal of excess amine in the parallel synthesis of amides. Desired products were obtained in excellent yields and purity with a sequestration time of less than 100 min at room temperature. After scavenging, the scavenger was easily filtered out and regenerated.

AIM: To investigate the mechanism and regulation of differentiation from bone marrow mesenchymal stem cells (MSCs) into hepatocytes and to find a new source of cell types for therapies of hepatic diseases. METHODS: MSCs were isolated by combining gradient density centrifugation with plastic adherence. The cells were cultured in osteogenic or adipogenic differentiation medium and determined by histochemical staining. MSCs were plated in plastic culture flasks that were not coated with components of extracellular matrix (ECM). When MSCs reached 70% confluence, they were cultured in low glucose Dulbecco’s modified Eagle’s medium supplemented with 10 mL/L fetal bovine serum, 20 ng/mL hepatocyte growth factor (HGF) and 10 ng/mL fibroblast growth factor-4 (FGF-4). The medium was changed every 3 d and stored for albumin, alpha-fetoprotein (AFP) and urea assay. Glycogen store of hepatocytes was determined by periodic acid-Schiff staining. RESULTS: By combining gradient density centrifugation with plastic adherence, we isolated a homogeneous population of cells from rat bone marrow and differentiated them into osteocytes and adipocytes. When MSCs were cultured with FGF-4 and HGF, approximately 56.6% of cells became small round and epithelioid on d 24 by morphology. Compared with the control, levels of AFP increased significantly from d 12 to 15.5±1.4 µg/L (t = 2.31, P