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Fritillaria Cirrhosa Bulbus (known as chuanbeimu in Chinese, FCB) is one of the most used Chinese medicines for lung disease. However, a variety of substitutes have entered the market, with Fritillaria Pallidiflora Bulbus (FPB) being the most common. Due to their similarity in appearance, morphology, and chemical composition but a large price difference, the FCB has frequently been adulterated with the FPB, posing a serious challenge to the distinction and quality of the FCB. Therefore, we aimed to distinguish FCB and FPB based on their main nine isosteroidal alkaloid contents and test the potential of chemometrics as a discrimination approach for evaluating quality. The nine major isosteroidal alkaloids were measured using a liquid chromatography with tandem mass spectrometry (LC–MS/MS) approach in 41 batches of FCB and 17 batches of FPB. Additionally, they were categorized and distinguished using the methods of hierarchical cluster analysis (HCA) and principal component analysis (PCA). Quantitative analysis revealed that the nine alkaloids were present in different amounts in the two types of Fritillariae bulbus. In FCB, the highest amount was peimisine (17.92–123.53 μg/g) and the lowest was delavine (0.42–29.18 μg/g), while in FPB, imperialine was higher (78.05–344.09 μg/g), but verticinone and verticine were less than the other seven alkaloids. The FCB and FPB were successfully classified and distinguished by the HCA and PCA. Taken together, the method has a good linear relationship (R2 > 0.9975). The LOD and LOQ of the nine alkaloids were in the range of 0.0651–0.6510 and 0.1953–1.9531 ng/mL, respectively. The intra- and inter-day precision were shown to be excellent, with relative standard deviations (RSDs) below 1.63% and 2.39%, respectively. The LC–MS/MS method in conjunction with HCA and PCA can effectively differentiate FCB and FPB. It may be a promising strategy for quality evaluation and control at the FCB. [ABSTRACT FROM AUTHOR]

The carbonylation of dimethyl ether to methyl acetate was carried out in a high-pressure flowed fix-bed reaction system over heterogeneous halide-free catalysts. The TG curves indicated that solid 12-tungstosilicic acid had a crystal structure (with six crystallization waters) identical to that of solid 12-tungstophosphoric acid, although they had different number of protons in molecules. The BET surface areas greatly increased by Cs substitution in HSiWO, and CsHSiWO showed a BET surface area of 206 m g. For the DME carbonylation at 473 K on 1 MPa under a CO/DME flow rate ratio of 18, CsHSiWO showed a DME conversion (6.7 %) higher than that over CsHPWO (4.6 %) because CsHSiWO had a larger surface area. CsHSiWO and CsHPWO showed high selectivity for methyl acetate of (98.0 and 97.5 %). By adding 1.0 wt% Rh in CsHSiWO, the DME conversion greatly increased from 6.7 to 30.8 % because a multiplier effect occurred between Rh and heteropoly acid. Rh/CsHSiWO showed a higher catalytic performance than those over the reported Rh/CsHPWO and Rh/H-MOR for the carbonylation. The DME conversion increased with increasing Rh loading from 0 to 1.0 wt% but became almost constant when Rh loading ranged from 1.5 to 3.0 wt% over Rh/CsHSiWO. With increasing the CO/DME ratio from 1.8 to 45, the DME conversion increased from 0.9 to 99.4 % over Rh/CsHSiWO at 473 K under 1 MPa. The 1 wt% Rh/CsHSiWO catalyst showed an initial DME conversion of 30.8 % (after 5 min on stream) but the DME conversion decreased to 23.3 % after 5 h on stream at 473 K on 1 MPa under a CO/DME flow rate ratio of 18. [ABSTRACT FROM AUTHOR]

The catalytic activities directing for an improvement of light olefin (C2′-C4′) selectivity were investigated on the RuMnLi/AlO Fischer-Tropsch synthesis catalysts in a low pressure fixed-bed reactor. The C2′-C4′ selectivities of RuMnLi/α-AlO and RuMnLi/β-AlO were a little higher than that of RuMnLi/γ-AlO. The difference seems to stem mainly from the crystallite sizes of metallic ruthenium, which is in the order: RuMnLi/γ-AlO > RuMnLi/β-AlO > RuMnLi/α-AlO, as evaluated from XRD, CO chemisorption and NH-TPD. The C3′ and 1-butene (1-C4′) were found to be predominantly formed over C2′ and, for C4, only n-butane and 1-C4′ were produced, but isobutane, isobutene and trans- or cis-2-butene were not formed, which is in sharp contrast with iron catalyst. Another reason for the improvement of C2′-C4′ selectivity is the Li effect, because, possibly, the secondary hydrogenation reaction of olefin intermediates could be suppressed on the Li-promoted catalyst. Thus, 50.2 % of C2′-C4′ selectivity was achieved at 300 °C and 0.5 MPa of CO/H using RuMnLi/α-AlO. [ABSTRACT FROM AUTHOR]

Cancer stem-like cells (CSLCs) are involved in cancer initiation, development, and metastasis, and microRNAs (miRNAs) play pivotal roles in regulating CSLCs. miRNA-based therapeutic strategy associated with CSLCs might promise potential new therapeutic approaches. In the present study, we found that miR-1290 was increased in CD133 cells. Antagomir-1290 significantly suppressed tumor volume and weight initiated by CD133 cells in vivo. Furthermore, antagomir-1290 significantly inhibited the proliferation, clonogenicity, invasion, and migration of CD133 cells by targeting fyn-related Src family tyrosine kinase. These findings provide insights into the clinical prospect of miR-1290-based therapies for non-small cell lung cancer. [ABSTRACT FROM AUTHOR]

A series of modified MoS-supported catalysts was investigated for the synthesis of mixed alcohols from synthesis gas in a high-pressure gas-solid flow reaction system. AlO-pillared montmorillonite (denoted as AlO-Mont) was prepared by calcining [AlOAl(OH)(HO)]-pillared montmorillonite at 673 K in air. AlO-Mont was an excellent support for MoS in the synthesis of mixed alcohols from synthesis gas. The MoS/AlO-Mont catalyst showed a CO conversion of 34.6 % and a selectivity for alcohols of 33.5 % at 553 K under 8 MPa. By introducing 3 wt% K (one of the alkali metals) in MoS/AlO-Mont, the CO conversion increased to 40.5 % and the selectivity for alcohols increased to 41.9 % at 553 K under 8 MPa. Furthermore, by increasing 5 wt% Ni (one of Fischer-Tropsch metals) in KMoS/AlO-Mont, the CO conversion increased to 51.8 % and the selectivity for alcohols increased to 50.5 % at 553 K under 8 MPa. With increasing reaction temperature, the CO conversion and the ratio of C higher alcohols to methanol increased but the selectivity for total alcohols greatly decreased due to the formation of hydrocarbons over KNiMoS/Al-Mont under 8 MPa. With increasing reaction pressure, the CO conversion and the ratio of C higher alcohols to methanol increased while the selectivity for total alcohols was almost constant over KNiMoS/Al-Mont at 553 K. KNiMoS/Al-Mont showed a good catalytic stability in a feed gas containing 10 ppm HS but gradually deactivated in a clean feed gas due to losing sulfur component during the reaction. [ABSTRACT FROM AUTHOR]

Re-modified Pt/SiO 2–Al 2O 3 catalysts, which were active for the direct hydrotreating of jatropha oil into C 18 hydrocarbons, were found to be effective for glucose transformation into C 6 alkanes. At 350 °C and glucose/catalyst weight ratio of 2, the highest glucose conversion of 100 % was achieved with selectivity to C 6 alkanes of 57.1 %. The reaction pathway involves glucose hydrocracking to form C 6 polyols, followed by deoxyhydration and subsequent C=C bond hydrogenation by synergistic effect of Pt and Re. [ABSTRACT FROM AUTHOR]

Some anesthetics have been suggested to induce Alzheimer's disease (AD) neuro-pathogenesis. Increasing evidence indicates that hyperphosphorylated tau plays a key role in the pathogenic events that occur in AD. Isoflurane has been shown to induce apoptosis, which leads to accumulation of amyloid-β (Aβ). We set out to investigate whether isoflurane can induce apoptosis by increasing hyperphosphorylated tau in Aβ-induced cells and the underlying mechanism. Cultured rat pheochromocytoma cells (PC12) were exposed to 20 mM Aβ alone or with 2 % isoflurane for 6 h. The cell viability was determined by MTT assay, and the apoptosis rate was detected by flowcytometry. Western blotting and immunocytochemical staining were performed to observe the protein expression of Bcl-2 family, tau phosphorylation of different sites, tau protein kinases and phosphatases. Additionally, lithium chloride was administered to all above groups to investigate the changes of apoptosis rate and protein expression. The apoptosis rate was significantly increased in Aβ group compared with the others groups, which was accompanied by bcl-2 decline, and the phosphorylation of glycogen synthase kinase-3β(GSK-3β) and tau of two sites increased. LiCl attenuated the cellular apoptosis by inhibition the level of tau phosphorylation. Isoflurane upregulated the level of phosphorylated GSK-3β, which phosphorylate tau at different sites, and aggravated the apoptotic rate of the Aβ-induced PC12 cells. It indicated that isoflurane-induced tau phosphorylation might play a role in the AD-like development. [ABSTRACT FROM AUTHOR]

Li and Mn have been used as secondary additives in Rh-Fe/TiO (Rh catalyst, TiO support, and Fe promoter) for the synthesis of ethanol from syngas. Introducing Li or Mn in Rh-Fe/TiO slightly decreased the catalytic activity but improved the ethanol selectivity. Li or Mn-added Rh-Fe/TiO showed high ethanol yield at high reaction temperatures because the catalytic activity increased at high reaction temperatures while the ethanol selectivity was kept at a high level. [ABSTRACT FROM AUTHOR]

Depressive disorders are devastating metal illness that can lead to deterioration in the social and occupational functioning of affected individuals. The etiology and pathophysiology of depression remain unknown. Present study was performed to better understand the underlying causes of depression. An experimental animal depression was induced in male BALB/c mice subjected to a chronic mild stress (CMS) procedure involving different stressor for consecutive 4 weeks. A cDNA microarray was employed to study the effects of CMS on the gene expression in cerebral cortex and hippocampus. 4-week CMS caused a significant reduction of 2% sucrose consumption. Morris water maze procedure showed impairment in cognitive function in stressed mice. Results of microarray showed that there were 102 and 60 genes were markedly affected by CMS treatment in cerebral cortex and hippocampus regions, respectively, including DNA damage/repair-related enzymes, anti-oxidant enzyme, and cyclin and cyclin-dependent kinase (CDK). These findings suggest that multiple biochemical effects play an important role the etiology of depression. [ABSTRACT FROM AUTHOR]

Polyoxocation ([AlO4Al12(OH)24(H2O)12]7+ and [Zr4(OH)14(H2O)10]2+)-pillared montmorillonites were prepared by ion exchange, and they were used as solid acid catalysts, in comparison to some other solid acids, for the selective hydrocracking of Fischer–Tropsch waxes to diesel-ranged hydrocarbons. XRD patterns and elemental analyses proved that the polyoxocations were successfully introduced into the interlayer region of the montmorillonites. N2 adsorption–desorption measurement indicated that polyoxocation-pillared montmorillonites have large BET surface areas (>230 m2 g−1), high thermal stability (>673 K), and large pores (comparing to those in zeolites). FT-IR spectra of chemisorbed pyridine indicated that polyoxocation-pillared montmorillonites possess both Lewis and Bronsted acid sites on the solid surface. Temperature-programmed desorption of ammonia indicated that the acidity strength of the polyoxocation-pillared montmorillonites was weaker than those of H–ZSM-5, H–Y, WO3/ZrO2, and Al2O3–SiO2. In the hydrocracking of Fischer–Tropsch (F–T) waxes, the acidity strength of the solid acids in bifunctional catalysts greatly influences the product composition. Pt-promoted H–Y afforded a high yield of gasoline-ranged hydrocarbons (>90%) while Pt-promoted H–ZSM-5 afforded a larger amount of gas products due to its strong solid acid sites. On the other hand, among various catalysts, Pt-modified polyoxocation-pillared montmorillonites afforded the highest yield of diesel-ranged hydrocarbons (>70%) due to the appropriately weak acid strength, high thermal stability, large BET surface area, and large pore size. Pt is necessary for the hydrocracking of F–T waxes because it enables hydrogenation/dehydrogenation. However, a high Pt loading on the catalyst produces more light hydrocarbons due to the stimulation of hydrogenolysis. High hydrogen pressure improved the selectivity for diesel-ranged hydrocarbons but decreased the conversion of F–T waxes due to the suppression of alkane dehydrogenation. The hydrocracking of F–T waxes at a low temperature with a large amount of catalyst for longer reaction time increased the yield of diesel-ranged hydrocarbons. [ABSTRACT FROM AUTHOR]

The dry reforming of CH4 (with CO2) at 800 °C under 1 MPa to synthesis gas and the synthesis of dimethyl ether (DME) from synthesis gas were combined. A Ni/(MgO)3·Al2O3 catalyst derived from Mg3Ni3Al2(OH)16CO3·xH2O hydrotalcite precursor showed a CH4 conversion of 85.4% after 5 min on stream for the dry reforming. The CH4 conversion decreased to 70.1% after 15 h on stream because the carbonaceous deposit formed during the reaction covered the active sites of Ni/(MgO)3·Al2O3 catalyst. The deactivated Ni/(MgO)3·Al2O3 catalyst was refreshed by calcining in air at 800 °C and subsequently reducing in H2. A mechanical mixed catalyst containing Cu/(ZnO)3·Al2O3 and Cs2.5H0.5PW12O40 (denoted as Cu/(ZnO)3·Al2O3 + Cs2.5) was used for the DME synthesis from syngas. Cu/(ZnO)3·Al2O3 + Cs2.5 showed a CO conversion of 38.5% and a DME selectivity of 63.8% at 260 °C under 1 MPa. A stable activity of Cu/(ZnO)3·Al2O3 + Cs2.5 had been maintained over 30 h in the DME synthesis. A two-stage process was designed for the DME synthesis from CH4 and CO2. Two fixed-bed reactors filled with Ni/(MgO)3·Al2O3 were connected in parallel (switching between reaction and refresh) for the CH4 dry reforming. A fixed-bed reactor filled with Cu/(ZnO)3·Al2O3 + Cs2.5 was connected in series with the two reactors filled with Ni/(MgO)3·Al2O3 to produce DME. The conversion of CH4 was kept at above 80% and the yield of DME was kept at above 20% after 30 h on stream for the DME synthesis from CH4 and CO2.A two-step process combining CH4 dry reforming to syngas and DME synthesis from syngas was designed for the DME synthesis from CH4 and CO2. The conversion of CH4 was kept at above 80% and the yield of DME was kept at above 20% after 30 h on stream in the two-stage processGraphic Abstract: The dry reforming of CH4 (with CO2) at 800 °C under 1 MPa to synthesis gas and the synthesis of dimethyl ether (DME) from synthesis gas were combined. A Ni/(MgO)3·Al2O3 catalyst derived from Mg3Ni3Al2(OH)16CO3·xH2O hydrotalcite precursor showed a CH4 conversion of 85.4% after 5 min on stream for the dry reforming. The CH4 conversion decreased to 70.1% after 15 h on stream because the carbonaceous deposit formed during the reaction covered the active sites of Ni/(MgO)3·Al2O3 catalyst. The deactivated Ni/(MgO)3·Al2O3 catalyst was refreshed by calcining in air at 800 °C and subsequently reducing in H2. A mechanical mixed catalyst containing Cu/(ZnO)3·Al2O3 and Cs2.5H0.5PW12O40 (denoted as Cu/(ZnO)3·Al2O3 + Cs2.5) was used for the DME synthesis from syngas. Cu/(ZnO)3·Al2O3 + Cs2.5 showed a CO conversion of 38.5% and a DME selectivity of 63.8% at 260 °C under 1 MPa. A stable activity of Cu/(ZnO)3·Al2O3 + Cs2.5 had been maintained over 30 h in the DME synthesis. A two-stage process was designed for the DME synthesis from CH4 and CO2. Two fixed-bed reactors filled with Ni/(MgO)3·Al2O3 were connected in parallel (switching between reaction and refresh) for the CH4 dry reforming. A fixed-bed reactor filled with Cu/(ZnO)3·Al2O3 + Cs2.5 was connected in series with the two reactors filled with Ni/(MgO)3·Al2O3 to produce DME. The conversion of CH4 was kept at above 80% and the yield of DME was kept at above 20% after 30 h on stream for the DME synthesis from CH4 and CO2.A two-step process combining CH4 dry reforming to syngas and DME synthesis from syngas was designed for the DME synthesis from CH4 and CO2. The conversion of CH4 was kept at above 80% and the yield of DME was kept at above 20% after 30 h on stream in the two-stage process [ABSTRACT FROM AUTHOR]

The Pd(OAc)2/Ti—Al-HMS/CH3OH catalyst system showed 61.2% selectivity for PO at 42.8% propylene conversion for the oxidation of propylene with molecular oxygen in an autoclave reactor at 373 K for 4 h. The catalyst is reusable using the filtration method or the vacuum distillation method after reaction. It is likely that a Ti cyclic peracid-like intermediate was formed in the system made up of a Ti site, an oxygen molecule and a methanol molecule. The Pd species activates the oxygen molecule and the Al site plays a role for stabilizing the Ti cyclic peracid-like intermediate to improve the yield of propylene oxide from the oxidation of propylene with molecular oxygen. [ABSTRACT FROM AUTHOR]

Ti- and Al-containing hexagonal mesoporous silicas (HMS) were synthesized at ambient temperature using dodecylamine as surfactant, and the resultant compounds were used as catalysts for the oxidation of propylene by molecular oxygen. Ti-Al-HMS, which was prepared by reaction of Ti(iso-OC3H7)4, Al(iso-OC3H7)3 and SiOC2H5)4 in an alcohol-aqueous solution in the presence of dodecylamine, showed 47.8 of conversion and 30.6 of selectivity for propylene oxide (PO) at 523K. The yield of PO over Ti-Al-HMS (14.6) was much higher than those over Ti-HMS (1.3) and Al-HMS (0.9) at the same reaction conditions. Ti-Al-HMS was also found to be more effective for PO formation than the supported catalysts (Ti/Al-HMS and Al/Ti-HMS) prepared by impregnation method. These results indicated that the simultaneous existence of Ti and Al in HMS was very important for improving the yield of PO from the oxidation of propylene, and the synthesis method influenced the catalytic activity of the Ti- and Al-containing HMS catalysts. [ABSTRACT FROM AUTHOR]

A series of Ce1-xCuxO2-δ mixed oxides were synthesized using a co-precipitation method and tested as catalysts for the steam reforming of methanol. XRD patterns of the Ce1-xCuxO2-δ mixed oxides indicated that Cu2+ ions were dissolved in CeO2 lattices to form a solid solution by calcination at 773K when x < 0.2. A TPR (temperature-programmed reduction) investigation showed that the CeO2 promotes the reduction of the Cu2+ species. Two reduction peaks were observed in the TPR profiles, which suggested that there were two different Cu2+ species in the Ce1-xCuxO2-δ mixed oxides. The TPR peak at low temperature is attributed to the bulk Cu2+ species which dissolved into the CeO2 lattices, and the peak at high temperature is due to the CuO species dispersed on the surface of CeO2. The Ce1-xCuxO2-δ mixed oxides were reduced to form Cu/CeO2 catalysts for steam reforming of methanol, and were compared with Cu/ZnO, Cu/Zn(Al)O and Cu/AL2O3 catalysts. All the Cu-containing catalysts tested in this study showed high selectivities to CO2 (over 97%) and H2. A 3.8wt% Cu/CeO2 catalyst showed a conversion of 53.9% for the steam reforming of methanol at 513K (W/F = 4.9 g h mol-1), which was higher than that over Cu/ZnO (37.9%), Cu/Zn(Al)O (32.3%) and Cu/AL2O3 (11.2%) with the same Cu loading under the same reaction conditions. It is likely that the high activity of the Cu/CeO2 catalysts may be due to the highly dispersed Cu metal particles and the strong metalsupport interaction between the Cu metal and CeO2 support. Slow deactivations were observed over the 3.8wt% Cu/CeO2 catalyst at 493 and 513K. The activity of the deactivated catalysts can be regenerated by calcination in air at 773K followed by reduction in H2 at 673K, which indicated that a carbonaceous deposit on the catalyst surface caused the catalyst deactivation. Using the TPO (temperature-programmed oxidation) method, the amounts of coke on the 3.8wt% Cu/CeO2 catalyst were 0.8wt% at 493K and 1.7wt% at 513K after 24h on stream. [ABSTRACT FROM AUTHOR]

Pd hydrotalcite (abbreviated as Pd(HT)) was dispersed on HMS (hexagonal mesoporous silica) by synthesizing Pd(HT) in an HMS suspension, and the resultant product (Pd(HT)/HMS) was used as a catalyst precursor for methanol decomposition to synthesis gas. The IR spectra of Pd(HT)/HMS showed all the bands of Pd(HT) and HMS with little shift, which indicated that Pd(HT) was synthesized in the Pd(HT)/HMS. Pd(HT)/HMS did not show the XRD pattern of Pd(HT) when the mass ratio of Pd(HT) to HMS was from 2/1 to 1/2. This indicated that Pd(HT) was formed in very small particles in the Pd(HT)/HMS after dispersion. Two endothermic peaks of Pd(HT) in the DTA curve shifted to lower temperatures in the Pd(HT)/HMS because the small Pd(HT) particles formed in the Pd(HT)/HMS were easily collapsed by heat treatment. Pd(HT)/HMS was thermally decomposed and reduced to form a supported Pd catalyst (abbreviated Pd(Mg(Al)O)/HMS) for methanol decomposition. Pd(Mg(Al)O)/HMS at 3.6 wt% showed a 52.5% conversion which was much higher than those over 3.6 wt% Pd(Mg(Al)O) (34.7%) and 3.6 wt% Pd/HMS (13.7%) for methanol decomposition at 523 K. The conversions of methanol over Pd(Mg(Al)O) and Pd/HMS increased with the increase in Pd loadings from 3.6 to 15 wt% and decreased when the Pd loadings were over 15 wt%. In contrast, the conversion over Pd(Mg(Al)O)/HMS increased with the increase in Pd loading even when the Pd loading was up to 30%. 30 wt% Pd(Mg(Al)O)/HMS showed a 91.7% conversion which was about twice that over 15 wt% Pd(Mg(Al)O) (47.1%) at 523 K. The Pd(Mg(Al)O)/HMS catalyst showed a larger BET surface area and Pd metal surface area than those of Pd(Mg(Al)O). By characterization using XPS analyses, the metal–support interaction between small Pd and small Mg(Al)O became stronger in the Pd(Mg(Al)O)/HMS catalyst. Large surface area, high Pd dispersion and strong metal–support interaction caused the high catalytic activity for methanol decomposition to synthesis gas over the Pd(Mg(Al)O)/HMS catalyst. [ABSTRACT FROM AUTHOR]

Isomerization of n-hexane and n-heptane was carried out over Cs2.5H0.5PW12O40 (denoted by Cs2.5) promoted by Pt which was introduced by either impregnation of H2PtCl6 or mechanical mixing of Pt/Al2O3 and over non-promoted Cs2.5H0.5PW12O40 in the presence of hydrogen at atmospheric pressure. The reaction temperature studied was relatively low (typically 453 and 423 K for n-hexane and n-heptane, respectively) and the hydrogen pressure was also rather low (standard conditions: feed = n-alkane 0.05 atm, H2 0.20 atm, N2 balance; W/F = 40 g h mol−1). Results were compared with those obtained under the same conditions for other Pt-promoted solid acids, where particular attention was paid to the time courses of the reaction (initial vs. stationary performance). Both the activity and selectivity of Cs2.5 at the initial stage (after 5 min) increased by the addition of the Pt component. Pressure dependencies of the rate at the initial stage were approximately first and −0.5th orders in alkane and hydrogen, respectively. Most remarkable was the suppression of the deactivation during the reaction in the presence of both Pt and hydrogen. For example, the mechanical mixture of Pt/Al2O3 and Cs2.5 (abbreviated as Pt+Cs2.5) showed little deactivation and much improved selectivity; resulting in high stationary conversion and selectivity; e.g., 98.4 and 92.1% selectivities for n-hexane and n-heptane at the conversions of 58.6 and 39.4%, respectively. Most of the results were well explained by a classical bifunctional mechanism, although other mechanisms are not all excluded. As for the other solid acids, the initial activity of Pt-promoted SO4/ZrO2 was high, but decreased rapidly. The deactivation was small with Pt-promoted H-ZSM-5, but the activity was low. The stationary yields of isomerized products were higher for Pt-promoted beta zeolite and Al-pillared saponite (tested only for n-heptane), although higher reaction temperatures were necessary. [ABSTRACT FROM AUTHOR]