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Dexmedetomidine (Dex) plays protective effects on brain ischemia-reperfusion (I/R) injury, but its mechanism remains unclear. In this study, we aimed to investigate whether Dex protects neurons against I/R injury by activating SIRT3 mediated autophagy. The oxygen glucose deprivation-reperfusion (OGD/R) model was constructed in HT22 cells. Different doses of Dex (50 ng/mL, 100 ng/mL and 500 ng/mL) were treated to observe the changes of autophagy and SIRT3 expression. Further, the mimic of SIRT3 and SIRT3 inhibitor were used to analyze the effects of Dex on the SIRT3 expression in HT22 cells. Additionally, the autophagy inhibitor and AMPK inhibitor were used to analyze the effects of Dex on SIRT3 mediated autophagy. The cells viability, oxidative stress and ATP were observed using assay kits. The mitochondrial membrane potential (MMP) and death were analyzed by flow cytometry. The degree of autophagy was observed by acridine orange staining. Western blotting was used to analyze the expression of autophagy related proteins and AMPK/mTOR pathway related proteins. After Dex treatment, the OGD/R induced cell injury was significantly improved through decreasing the levels of LDH and H

A volatile solid additive, 2,6-dichloroiodobenzene (DCIB), was introduced into PM6:Y6-based devices, and a better phase separation morphology was gained due to the enhanced intermolecular interaction and prospective stability with little decay during 25 days.

The third component played an increasingly significant role in polymer solar cells (PSCs), especially for the morphological impact. Here, we use a ternary polymer donor (TBFCl50-BDD) and organic small molecule acceptor (BTP-4F) as the main material and introduce a third component (PC71BM) to enhance the morphology of the photoactive layer and result in improved device performance. The TBFCl50-BDD:BTP-4F based PSCs only exhibited an efficiency of 10.58%, while The power conversion efficiency of ternary device (TBFCl50-BDD:BTP-4F:PC71BM) reached 13.15%. Importantly, the introduction of PC71BM can not only improve the morphology of the active layer and promote more efficient exciton transport, but also influence the molecular arrangement for better crystallization performance. This work offers an effective method for optimization of the morphology to enhance the properties of PSCs.

Conventional additives like 1,8-diiodooctane (DIO) and 1-chloronaphthalene (CN) play an essential role in optimization of blend film morphology of polymer solar cells (PSCs). However, they have halogenated elements in their end groups, which are harmful to the environment and humans, limiting large-scale applications. In this work, a novel non-toxic and non-halogen additive, dibenzyl ether (DE), was introduced into PTB7-Th:PC71BM based PSCs, and the role of the DE additive was systemically investigated. The results showed that DE additive can not only adjust phase separation and optimize the morphology of blend film, but also promote the mobility of hole and electron. The grazing-incidence small-angle X-ray scattering (GISAXS) showed that the introduction of DE increased the interface area between PTB7-Th and PC71BM, which can promote exciton dissociation, and achieve better charge transport. Transient photovoltage (TPV) and transient photocurrent (TPC) measurements show that carrier recombination of the additive-containing devices can be effectively inhibited with improved charge transport efficiency of the active layer. Consequently, the devices with DE additive achieve power conversion efficiency (PCE) of 9.53% and a fill factor (FF) of 70.41%. Our non-toxic and non-halogen additive provides a potential solution for the preparation of environmental-friendly PSCs in the future.

Particle mixing and segregation behavior in an Air Dense Medium Fluidized Bed with binary mixtures of solid particles were investigated for dry coal beneficiation. Magnetite mixed with coal/gangue/sand particles belonging to Geldart B/D group were tested individually for the bed density adjustment. The effects of operating parameters including particle density ratio, particle size ratio, mixture composition, superficial gas velocity, and fluidized bed height on the mixing and segregation pattern were examined. The results demonstrated that the segregation becomes more severe with increasing density difference of binary mixtures. An increase in particle size ratio may also lead to partial segregation. Mixing and segregation of binary systems are almost independent of lower excess gas velocity and initial bed height when it is over 15 cm. Moreover, a mixing index was employed to evaluate the mixing and segregation performance, and the criteria for good mixing to achieve the bed density adjustment were identified.

Background: Glioma is the most common brain tumor with poor prognosis all over the world. Anesthetics have been demonstrated to have important impacts on cell migration and invasion in different cancers. However, the underlying mechanism that allows anesthetics-mediated progression of glioma cells remains elusive. Methods: Sevoflurane (Sev), a class of common anesthetics, was used to expose to U87-MG and U251 cells. The expressions of microRNA-146b-5p (miR-146b-5p) and matrix metallopeptidase 16 (MMP16)were measured by quantitative real-time polymerase chain reaction or western blot. Transfection was performed in glioma cells with miR-146b-5p inhibitor, inhibitor negative control, MMP16 overexpression vector, empty vector, small interfering RNA against MMP16 or scramble. Cell migration and invasion were analyzed by the trans-well assay. The interaction between miR-146b-5p and MMP16 was explored by luciferase activity and RNA immunoprecipitation assays. Results: Sev treatment inhibited migration and invasion of glioma cells. The expression of miR-146b-5p was enhanced and MMP16 protein was decreased in glioma cells after exposure of Sev. Knockdown of miR-146b-5p or overexpression of MMP16 reversed Sev-induced inhibition of migration and invasion of glioma cells. Moreover, MMP16 was indicated as a target of miR-146b-5p and its silencing attenuated the regulatory role of miR-146b-5p abrogationin Sev-treated glioma cells. Conclusion: Sev impeded cell migration and invasion through regulating miR-146b-5p and MMP16 in glioma, indicating a novel theories foundation for the application of anesthetics like Sev in glioma.

Minimum fluidization velocity of binary mixtures is one of the most important parameters when applying an Air Dense Medium Fluidized Bed for dry coal beneficiation. Measurements of minimum fluidization velocities were carried out for binary mixtures of magnetite and sand/gangue/coal particles. The experimental results showed that the minimum fluidization velocity of binary mixtures remained almost unchanged when the volume fraction of magnetite particles was above 50%, whereas it varied significantly when the volume fraction of magnetite particles was below 50%. A general correlation based on the Cheung equation has been developed for predicting the minimum fluidization velocity of binary mixtures in terms of particle size ratio, volumetric composition and incipient fluidization velocity of each component. The extended Cheung equation is in reasonable agreement with almost all the available experimental data in the present work and the literature, and it can be used to estimate accurately the minimum fluidization velocity of binary mixtures of medium particles for the ADMFB and other similar fluidized bed operations.

Knowledge of the division of gas flow between the bubble and dense phases is important for modelling and operation of bubbling fluidized beds. The two-phase theory of fluidization, which suggested that the bubble flow rate being equal to the excess gas flow above the incipient fluidization, has been proved to be an overestimation in most cases. While the two-phase theory has been modified by introducing a correction factor (Y), most previous studies were conducted for Geldart Group A powders. In the present work, the contribution to predict the parameter Y for Geldart Group B and D particles has been formulated based on almost all the available experimental data. The experimental results demonstrated that the Y value increases with decreasing particle size or density and increasing excess gas velocity. A new correlation has been developed to estimate the Y value for Geldart Group B and D particles Y = 1.72 Ar − 0.133 U g − U mf 0.024 with an overall standard deviation of 19%. It only requires the knowledge of Archimedes number and excess gas velocity. This correlation is in reasonable agreement with almost all the available data in literature and the present work.

Air Dense Medium Fluidized Bed (ADMFB) is deemed to be one of the most efficient methods for dry coal beneficiation. In the present work, a semi-industrial ADMFB system in continuous operation was utilized to study the effects of operating gas velocity, feed coal size, and mixture composition of medium particles on the coal beneficiation in industrial practice. Binary mixtures of magnetite and fine coal particles were used as the medium material, and four different feed coal samples with the size ranges of −50 + 25, −25 + 13, −13 − 6, and −6 + 2 mm were tested individually. The experimental results showed that the influence of excess gas velocity on the dry coal separation is relatively small in the lower flow rates. The separation density and probable error increase with the decreasing of feed coal size, regardless of the type of feed coal. The separation density can be continually reduced by further increasing the fraction of fine coal in the medium material, with the compromise of the increased probable error. Moreover, the ash content and calorific value of −50 + 6 mm coarse coal can be effectively upgraded, but the beneficiation of −6 + 2 mm fine coal was less efficient.

Minimum fluidization velocity is one of the most important fluidization characteristics when applying an Air Dense Medium Fluidized Bed to dry coal beneficiation. Measurements were carried out for magnetite particles (150–300 μm) and the binary mixtures of magnetite mixed with sand/gangue/coal particles (300–425 μm) to determine the influence of bed inventory on the characteristics at incipient fluidization state. The experimental results demonstrate that the minimum fluidization velocities of both single and binary mixtures of solid particles increase with increasing bed mass, which has not properly accomplished by the existing equations. The correlation proposed by Wen and Yu has been modified to predict the minimum fluidization velocity as a function of bed inventory. It only requires the knowledge of Archimedes number and the pressure drop of fluidized bed. This correlation is in reasonable agreement with almost all available data in the literature and the present work.

In this study, a uniform and stable vibrated dense medium fluidized bed (VDMFB) with Geldart B magnetite powder was formed, where it was considered suitable for 1–6 mm coal separation. The ...

This study analyzes the relationship and the issues between iron ore market from demand and supply side. It empirically explains how and why the import iron ore price in China fluctuates through Baltic Dry Index, Dollar Index, iron ore production, volume of import iron ore, and also compares the forecast ability between Vector Error Corrected Model (VECM) and ARIMA model. This paper concludes the following finds. Firstly, there is no structural break and seasonality. The data are first degree stationary and have 1 cointegration relationship between variables. In addition, the impulse response function shows that the import iron ore price is positively sensitive to BDI and negatively sensitive to Dollar Index, and it reveals the fact that China has less power to influence the iron ore price even if it has been the largest buyer. Finally, forecast ability assessment shows that VECM outperforms ARIMA model.

BACKGROUND: The TWIK-related potassium channel (TREK-1) can be regulated by different stimuli. However, it is not clear whether some antiarrhythmics affect the activity of TREK-1. In the present study, the effect of bepridil on the TREK-1 currents is investigated. METHODS: In a TREK-1 stably-expressed HEK-293 cell line (HEK-TREK-1), U251MG cells, and isolated mouse ventricular myocytes, the TREK-1 current and action potentials were recorded by the patch-clamp technique. The standard voltage protocol was a 200 ms constant potential at 20 mV, followed bya 500 ms ramp from –90 to +20 mV (HEK-TREK-1) or +80 mV (U251MG cells and myocytes) every 10 s. The currents at +20 mV or +80 mV were used for analysis. The docking study of bepridil’s binding model in the TREK-1 channel was performed using the Swissdock web service. RESULTS: In HEK-TREK-1 cells, BL1249 induced a significantly large outwardly rectifying current with similar baseline TREK-1 current characteristic, with a reversal potential (−70 mV). The concentration of half-maximal activation (EC(50)) of BL1249 was 3.45 µM. However, bepridil decreased the baseline TREK-1 currents, with a concentration of half-maximal inhibition (IC(50)) 0.59 µM and a Hill coefficient of 1.1. Also, bepridil inhibited BL1249-activated TREK-1 currents, with an IC(50) 4.08 µM and a Hill coefficient of 3.22. The outside-out patch-clamp confirmed bepridil inhibited BL1249-activated TREK-1 currents. In U251MG cells and myocytes, BL1249 activated outwardly rectifying endogenous TREK-1 currents, which could be inhibited by bepridil. BL1249 (10 µM) could decrease the peak value and reduce the duration of the action potential. Bepridil (10 µM) prolonged the duration of action potential of myocytes. The docking study revealed that bepridil might affect the K(+) pore domain and the M4 modulator pocket. CONCLUSIONS: Bepridil may be a blocker for the TREK-1K(+)channel at a clinically therapeutic concentration, providing a new mechanism of TREK-1 regulation and bepridil's antiarrhythmic effect.

Fine lignite dry cleaning, which has the significant advantage of without process water, is becoming increasingly important due to global water shortage. Lignite particles of various compositions were experimentally studied in a vibrated gas-fluidized bed. This is the first report of the size-based segregation of fine particles in the vibrated gas-fluidized bed. Experimental results demonstrate that the –2 +0.5 mm lignite particles play an irreplaceable role in particle fluidization and segregation. To ensure good separation performance, the minimum content of –2 +0.5 mm lignite particles should be 13%. Separation results show that for –6 +0.5 mm lignite particles, the ash contents of clean coal and tailings are 23% and 45%, with the corresponding yields of 82% and 18%, respectively, which shows good separation performance.

The fluidization behavior of a binary mixture of Geldart D type particles in a shallow vibrated gas-fluidized bed (VFB) was systematically studied by using a high-speed dynamic camera. This study drew a comparison between the fluidization of a VFB and a conventional gas-fluidized bed (CFB). The results show that the characteristic air velocities in a VFB, such as the minimum fluidization velocity, the minimum bubbling velocity and the minimum slugging velocity, have considerable reductions in comparison with that in a CFB. It is indicated that the vibration significantly changes the gas-solid two-phase flow structure and improves the dispersion uniformity of air flow in the bed. The air pressure waves, as the main transmission mode of vibration energy, can improve the air-solid contact efficiency and organize the excess fluidizing air to form periodic slugs. In a VFB of Geldart D type particles, there are four distinct fluidization regimes: static bed, bubbling fluidization, slugging fluidization and turbulent fluidization. The results show that a good performance of density segregation in a VFB of Geldart D type particles happens in the stage of gentle slugging.

A one-pot, three-component reaction of aromatic aldehydes, 2-hydroxy-1,4-naphthoquinone, and 3,4-methylenedioxyphenol has been reported for the synthesis of novel 7-aryl-6H-benzo[h][1,3]dioxolo[4,5-b]xanthene-5,6(7H)-diones using environmentally benevolent para-toluene sulfonic acid (p-TSA) as the catalyst. This methodology provides a mild and fast route to diverse pyran derivatives in moderate to good yields.

A green and convenient synthetic method has been described for the synthesis of 2-hydroxy-3-((5-methyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)(phenyl)methyl)naphthalene-1,4-dione derivatives by a one-pot, four-component reaction of aromatic aldehydes, 2-hydroxy-1,4-naphthoquinone, hydrazine derivatives, and ethyl acetoacetate catalyzed by MgCl2 in ethylene glycol. Simplicity, short reaction time, high yield, and an eco-friendly catalyst are the main advantages of this method.

Dry beneficiation of fine coal is increasingly significant for the clean utilization of coal resources in drought regions. In this paper, a continuous vibrated gas-fluidized bed separator was developed for fine coal dry beneficiation. The fluidization behavior and the kinematic properties of fine coal particles in this separator were systematically investigated. The results show that the bed expansion increases linearly with the superficial air velocity and theoretically, higher bed expansion benefits the hindered settling process of fine coal particles. However, larger superficial air velocity will induce intense fluctuation in bed surface. The conveying velocity of particles is mainly determined by the vibration angle and a predicted model is established by the nonlinear regression analysis. The kinematic properties underlying the particles diffusion in the separator are theoretically analyzed and a theoretical model of bed height distribution is established and this model fits the measured value well. The beneficiation performance of this separator is also evaluated by separating −3 + 1 mm fine coal. The results show that the probable error, E , is 0.225, indicating a continuous vibrated gas-fluidized bed separator can achieve a satisfactory performance.

Dry beneficiation technology of an air-dense medium fluidized bed offers a number of advantages and expands the choices of efficient dry coal cleaning. Recently, the applications of coal beneficiation by the air-dense medium fluidized bed mainly focus on the size fraction of −50 + 6 mm, but it is difficult to separate −6 mm fine coal using the conventional deployment of dense medium. The objective of this study is to expand the lower separation limit of an air-dense medium fluidized bed by using improved magnetite medium. The smaller magnetite powders of narrow size range having lower minimum fluidization velocity could produce a homogeneous gas-solid fluidized bed, which will be in favor of fine coal separation. The experimental results demonstrate that, for −6 + 3 mm fine coal, the tailing product, having the yield, high-ash content, and total sulfur of 34.39%, 70.27%, and 3.42%, respectively, is efficiently removed. Consequently, the clean coal with a yield of 27.33% has a significant reduction of ash ...

The effects of polyethers (polyethylene glycol-block-polypropylene glycol-block-polyethylene glycol copolymer (PEG-PPG-PEG) and polyethylene glycol (PEG)) on the chitosan (CS)-Pd (II) gel beads catalysts prepared by a co-precipitation method have been studied. The blending of the polyethers led to an acceleration effect of the sol–gel transition. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) results showed that most of the blended polyethers component was efficiently, selectively, dissolved by water, but, unexpectedly, no pore structure was obtained. It was found that the blending of the polyethers can promote better phase dispersion of the Pd species in the CS matrix. The extracted CS/PEG-PPG-PEG/Pd gel beads catalysts had higher catalytic performance than extracted CS/PEG/Pd or CS/Pd gel beads catalysts alone due to its better phase dispersion of Pd0 species and stronger intermolecular interactions.

An efficient catalyst-free synthesis of 3′-benzoyl-4′,5′-diphenyl-2H-spiro[acenaphthylene-1,2′-pyrrolidin]-2-one derivatives via one-pot 1,3-dipolar cycloaddition of acenaphthenequinone, arylmethyl amines, and chalcones with high regioselectivity is described. The structure of the cycloadducts were characterized by infrared, high-resolution mass spectrometry (electrospray ionization), 1H NMR, and 13C NMR spectra, and the structure of 4a was confirmed using x-ray single-crystal structure analysis.

A series of 3-pyrazolylisoindolinone derivatives were synthesized by a concise, efficient, three-component reaction of a 2-formylbenzoic acid, a primary amine (or ammonium hydroxide), and a pyrazolone under catalyst-free conditions. This novel procedure has the advantages of easy handling, mild reaction conditions, and a wide substrate scope, and can be performed as a one-pot operation.

Fine coal dry preparation becomes more and more significant for countries and regions which have insufficient processing water. Fine coal separation based on density segregation in a vibrated gas-fluidized bed (VGFB) does not use water and dense medium and has a good separation performance. This paper attempted to carry out a systematic process analysis of fine coal preparation in a VGFB. Particles distribution characteristics were experimentally studied and it was pointed out that a VGFB of fine coal having a periodic slugging behavior could obtain a good performance of density segregation. Furthermore, the effects of several operational factors on the stratification performance were studied using Box–Behnken response surface methodology (RSM) and the RSM analysis indicated that several factors including superficial air velocity, vibration intensity and bed height all had significant effects. Among these factors, the superficial air velocity behaved considerably more significant than others. Under the optimal operational conditions determined by the RSM analysis, the results of − 6 + 3 mm fine coal preparation in a VGFB showed that the yield and ash content are 76.68% and 25.15% as to the clean coal product, and 23.32% and 60.08% as to the gangue product, respectively. The probable error E value is 0.18, indicating a good performance of fine coal dry preparation in a VGFB.

The pathophysiology of nasal polyps (NP) remains unclear, however, several ion channels may participate. Whether transient receptor potential canonical (TRPC) channel play a role in NP remains unknown. We investigated expression of TRPC, eosinophil infiltration, IL-6, and NF-κB in 58 patients with NP and 35 control subjects using hematoxylin-eosin (HE) staining, immunohistochemistry, real-time fluorescence quantitative reverse transcription PCR (real-time RT-PCR), Western blotting, and calcium imaging. Compared with normal nasal mucosa, TRPC5 mRNA and protein expression increased in NP. Eosinophil counts, IL-6 expression, and phosphorylation levels of NF-κB were higher in NP than in normal mucosa. TRPC5 expression was positively correlated with eosinophils, IL-6, and phosphorylation levels of NF-κB. Blocking of TRPC5 channel decreased store-operated calcium influx, IL-6 expression, and phosphorylation levels of NF-κB in blood eosinophils from patients with NP. In conclusion, TRPC5 was upregulated in NP and played an important role in development of NP by activating eosinophilic inflammation and NF-κB signal pathways.

An efficient one-pot synthesis of 5H-spiro[benzo[7,8]chromeno[2,3-c]pyrazole-7,3′-indoline]-2′,5,6(9H)-trione derivatives via a four-component reaction of hydrazine hydrate, β-keto esters, isatins, and 2-hydroxynaphthalene-1,4-dione catalyzed by MgCl2 in ethanol is reported. This reaction provides the advantages of excellent yields, environmental friendliness solvent, simple workup procedure, and short reaction time.

The periodic slugging behavior of Geldart D particles in a vibrated gas-fluidized bed (VFB) is favorable for some applications involving the processes of particles stratification, especially for fine coal beneficiation in a VFB. It is of great significance to conduct systematic studies on slug formation, slug coalescence and growth, slug rising velocity, and slugging frequency in a VFB of Geldart D particles. The slug formation model is proposed based on theoretical analysis and indicates that the vibration amplitude, the vibration frequency, and the superficial air velocity all have significant effects on the slugging behavior. Also, the comparison of predicted values and measured values of the slug height at its initial formation verifies that the slug formation model has high prediction accuracy. The dynamic of the coalescence of bubbles into an adjacent slug is qualitatively studied and the correlations of the slug height and the slug rising velocity are established, respectively. The results show tha...

The distribution of bed density in an Air Dense Medium Fluidized Bed (ADMFB) with single and binary mixtures of solid particles was investigated for dry coal beneficiation. The effects of particle properties, superficial gas velocity, and mixture composition on the axial distribution of fluidized bed density were examined. A lower density region at the bottom of the fluidized bed with single particles has been observed, whereas the bed density at the upper part remains almost consistent. The increasing excess gas velocity does not change this trend although decreasing the overall bed density, however the binary mixtures of solid particles can be used to balance this non-uniform density distribution. A new equation has been derived to predict the bed density distribution, considering particle properties and fluidization characteristics. This correlation successfully accounts for the estimation of density distribution in ADMFB involving both single and binary mixtures of Geldart B and/or D particles.

Background The process of brain death induces acute lung injury in donors and aggravates ischemia–reperfusion injury (IRI) in grafts. Hydrogen, a new anti-oxidant, attenuates IRI in several organ transplant models. We examined whether 2% inhaled hydrogen would show favorable effects on lung grafts from brain-dead donor rats. Methods Brain-dead donor rats inhaled mixed gases with either 50% oxygen and 50% nitrogen or mixed gases with 2% hydrogen, 50% oxygen and 48% nitrogen for 2 hours. The recipients inhaled the same gas as the donors and were euthanized 2 hours after lung transplantation. Results Hydrogen improved PaO 2 /FIO 2 and PVO 2 /FIO 2 from the arterial and pulmonary venous blood in recipients and decreased the lung injury score in grafts from brain-dead donors. Hydrogen decreased the amount of IL-8 and TNF-α in serum, inhibited the activity of malondialdehyde and myeloperoxidase, and increased the activity of superoxide dismutase in the lung grafts from brain-dead donors. Furthermore, hydrogen decreased the apoptotic index of the cells and inhibited the protein expression of intercellular adhesion molecule-1 and caspase-3 in lung grafts from brain-dead donors. Conclusions Hydrogen can exert protective effects on lung grafts from brain-dead donors through anti-inflammatory, anti-oxidant and anti-apoptotic mechanisms.

For most atom interferometers, the vibration isolation unit is applied to reduce vibration noise. In our experiment, instead of isolation, the vibration signals are monitored, and combining with the sensitive function, the compensation phase shift for the atom interferometer is obtained. We focus on the correction over a wide spectrum rather than on “monochromatic” frequencies. The sensitivity of the atom gravimeter can be upgraded by a factor of more than two. Furthermore, we demonstrate that the atom interferometer can still produce a good measurement result without passive vibration isolation in extremely noisy environments by using vibration compensation.

Modulation transfer spectroscopy (MTS) is widely used in an optical laboratory for laser frequency stabilization. There have been many theoretical and experimental papers on this spectroscopic method. However, most of the works focus on the cycling transitions like the D2 line of rubidium. In this paper, the MTS for noncycling transitions is investigated. We consider the D1 line of rubidium whose modulation transfer spectrum has been determined and compared to the polarization spectrum. It is found that the slope of the modulation transfer signal is sharper than the polarization spectrum. The performance of laser frequency locking based on the MTS method is better than that of the polarization spectroscopy method. The dependence of the signal amplitude on the temperature of the vapor cell was analyzed, and the high signal-to-noise-ratio spectra are achieved for D1 open transitions. The obtained results provide an effective spectroscopic method for the robust frequency locking of a laser at a wavelength of 795 nm.

The two-pore domain potassium (K2P) channel TREK-1 is recognized as a new and major candidate of cardiac stretch-activated potassium current and play a key role in the pathogenesis of human cardiac arrhythmias and heart failure. However, there is little study about the effect of antiarrhythmic drugs

A series of 3-pyrazolylisoindolinone derivatives were synthesized by a concise, efficient, three-component reaction of a 2-formylbenzoic acid, a primary amine (or ammonium hydroxide), and a pyrazolone under catalyst-free conditions. This novel procedure has the advantages of easy handling, mild reaction conditions, and a wide substrate scope, and can be performed as a one-pot operation.

An efficient catalyst-free synthesis of 3′-benzoyl-4′,5′-diphenyl-2H-spiro[acenaphthylene-1,2′-pyrrolidin]-2-one derivatives via one-pot 1,3-dipolar cycloaddition of acenaphthenequinone, arylmethyl amines, and chalcones with high regioselectivity is described. The structure of the cycloadducts were characterized by infrared, high-resolution mass spectrometry (electrospray ionization), 1H NMR, and 13C NMR spectra, and the structure of 4a was confirmed using x-ray single-crystal structure analysis.

An efficient one-pot synthesis of 5H-spiro[benzo[7,8]chromeno[2,3-c]pyrazole-7,3′-indoline]-2′,5,6(9H)-trione derivatives via a four-component reaction of hydrazine hydrate, β-keto esters, isatins, and 2-hydroxynaphthalene-1,4-dione catalyzed by MgCl2 in ethanol is reported. This reaction provides the advantages of excellent yields, environmental friendliness solvent, simple workup procedure, and short reaction time.

An efficient catalyst-free synthesis of 3′-benzoyl-4′,5′-diphenyl-2H-spiro[acenaphthylene-1,2′-pyrrolidin]-2-one derivatives via one-pot 1,3-dipolar cycloaddition of acenaphthenequinone, arylmethyl amines, and chalcones with high regioselectivity is described. The structure of the cycloadducts were characterized by IR, HRMS (ESI), 1H-NMR, 13C-NMR spectra and the structure of 4a was confirmed using X-ray single crystal structure analysis.