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This study proposes two different methods of photocatalytic-controlled and visible light-induced selective oxidation of pyridiniums with air as the terminal oxidant. The key to these transformations is to choose the appropriate light source and photocatalyst. Pyridiniums are successfully converted into pyrroles through oxygen-mediated cycloaddition, proton-coupled electron transfer (PCET), pyridine ring opening, and recyclization. The other route is that pyridiniums selectively form 4-carbonyl pyridines through free radical rearrangement/aerobic oxidation under the catalysis of cobalt (II).

An asymmetric synthesis of (8Z,21R)-21-methylpentatriacont-8-ene, the sex pheromone of the yellow-spotted longicorn beetle Psacothea hilaris, has been achieved using Evan’s induction as the key step. Based on the asymmetric methylation product of chiral (R)-4-benzyl-1,3-oxazolidin-2-one, the carbon chain of the target molecule was assembled through a C5+C12+C11+C8 sequence. (2R)-4-(Benzyloxy)-2-methylbutan-1-ol, which can be obtained from γ-lactone following Evan’s protocol, was connected to a C12 alkyl group. The chiral methyl group remained the key moiety (97% ee). After another Wittig reaction and catalytic hydrogenation step, the designed key intermediate (13R)-13-methylheptacosan-1-ol was obtained. Finally, after oxidation and Wittig reaction, the synthesis of the target molecule was completed in 10 linear steps with an ultra-high overall yield of 36.2%.

Ammonia is a vital intermediate in the hydrogen desorption process of Metal-N-H system. KH has strong reactivity with NH3 to form KNH2. We speculate that KNH2 is also an intermediate formed during hydrogen desorption of the potassium-doped M-N-H systems. In this research, the dehydrogenation performance of the KNH2-doped LiNH2 and LiH composition was first studied. Compared with the broad dehydrogenation curve of the composite material of LiNH2 and LiH without the catalyst, the dehydrogenation curve of 0.05 mol KNH2-doped composite material was significantly narrowed. The initial and peak dehydrogenation temperature of the composite to which 0.05 mol of KNH2 was added was lowered remarkably. Besides, the cyclic dehydrogenation properties of the LiNH2 and LiH system was also significantly enhanced by the introduction of KNH2. The cyclic conversion of KNH2 to KH is the main reason for the enhancement of the hydrogen evolution performance of the LiNH2–LiH system doped with KNH2. We found the KNH2-doped Li–N–H system exhibits similar dehydrogenation property with that of the KH-doped Li–N–H system. This work proves that KNH2 plays a key role in improving the hydrogen desorption performances of the potassium-doped M-N-H systems.

The eCO2RR activity is correlated to the internal structural character of the catalyst. We employed two types of structural models of porphyrin-based MOFs of PCN-222(Cu) and PCN-224(Cu) into heterogeneous catalysis to illustrate the effect of structural factors on the eCO2RR performance. The composite catalyst PCN-222(Cu)/C displays better activity and selectivity (η = 450 mV, FEHCOOH = 44.3%, j = 3.2 mA cm−2) than PCN-224(Cu)/C (η = 450 mV, FEHCOOH = 34.1%, j = 2.4 mA cm−2) for the CO2 reduction to HCOOH in the range of −0.7–−0.9 V (vs. RHE) due to its higher BET surface area, CO2 uptake, and a larger pore diameter. It is interesting that PCN-224(Cu)/C displays better performance in the range of −0.4–−0.6 V (vs. RHE) due to its greater heat of adsorption, Qst and a higher affinity for CO2 molecule, which could promote the capture of CO2 onto the exposed active sites. As a result, PCN-224(Cu)/C exhibits better stability for the long-term electrolysis.

Background: Erythrina variegata has been widely used as a traditional medicine. Objective: The study was designed to evaluate the anxiolytic and anti-depressant effects of an extract from Erythrina variegata. Methods: The extract was evaluated for anxiolytic and anti-depressant action using the elevated plus maze, light/dark box, open field, forced swimming and tail suspension tests in mice. The mechanism of action was further elucidated using high-performance liquid chromatography with fluorescence detection methods to assay the levels of five neurotransmitters in brain. Results: The extract exhibited significant increase in the percentage of the open arms entries and the time spent in the open arms in the elevated plus maze test. The results of the light/dark box test revealed a significant increase in the amount of time spent in the light chamber. Extract- treated mice also produced significant increase in the number of crossings and rearings in the open field test.In the forced swimming and tail suspension tests, the extract was able to promote significant decrease in the immobility time. In addition, the extract significantly altered the levels of five neurotransmitters in the brain tissue. Conclusion: These findings suggest that Erythrina variegata presents potential anxiolytic and anti-depressant activity, and the mechanism may be related to the alteration of neurotransmitter levels. Keywords: Anxiolytic; anti-depressant; Erythrina variegata; elevated plus maze; forced swimming; neurotransmitters.

The increasing resistance of plant diseases caused by phytopathogenic fungi highlights the need for highly effective and environmentally benign agents. The antifungal activities of Cnidium monnieri fruit extracts and five isolated compounds as well as structurally related coumarins against five plant pathogenic fungi were evaluated. The acetone extract, which contained the highest amount of five coumarins, showed strongest antifungal activity. Among the coumarin compounds, we found that 4-methoxycoumarin exhibited stronger and broader antifungal activity against five phytopathogenic fungi, and was more potent than osthol. Especially, it could significantly inhibit the growth of Rhizoctonia solani mycelium with an EC50 value of 21 μg mL-1 . Further studies showed that 4-methoxycoumarin affected the structure and function of peroxisomes, inhibited the β-oxidation of fatty acids, decreased the production of ATP and acetyl coenzyme A, and then accumulated ROS by damaging MMP and the mitochondrial function to cause the cell death of R. solani mycelia. 4-Methoxycoumarin presented antifungal efficacy in a concentration- dependent manner in vivo and could be used to prevent the potato black scurf. This study laid the foundation for the future development of 4-methoxycournamin as an alternative and friendly biofungicide.

Mitochondrial dysfunction in neurons has been implicated in hypoxia-ischemia-induced brain injury. Although mesenchymal stem cell therapy has emerged as a novel treatment for this pathology, the mechanisms are not fully understood. To address this issue, we first co-cultured 1.5 × 105 PC12 cells with mesenchymal stem cells that were derived from induced pluripotent stem cells at a ratio of 1:1, and then intervened with cobalt chloride (CoCl2) for 24 hours. Reactive oxygen species in PC12 cells was measured by Mito-sox. Mitochondrial membrane potential (?Ψm) in PC12 cells was determined by JC-1 staining. Apoptosis of PC12 cells was detected by terminal deoxynucleotidal transferase-mediated dUTP nick end-labeling staining. Mitochondrial morphology in PC12 cells was examined by transmission electron microscopy. Transfer of mitochondria from the mesenchymal stem cells derived from induced pluripotent stem cells to damaged PC12 cells was measured by flow cytometry. Mesenchymal stem cells were induced from pluripotent stem cells by lentivirus infection containing green fluorescent protein in mitochondria. Then they were co-cultured with PC12 cells in Transwell chambers and treated with CoCl2 for 24 hours to detect adenosine triphosphate level in PC12 cells. CoCl2-induced PC12 cell damage was dose-dependent. Co-culture with mesenchymal stem cells significantly reduced apoptosis and restored ?Ψm in the injured PC12 cells under CoCl2 challenge. Co-culture with mesenchymal stem cells ameliorated mitochondrial swelling, the disappearance of cristae, and chromatin margination in the injured PC12 cells. After direct co-culture, mitochondrial transfer from the mesenchymal stem cells stem cells to PC12 cells was detected via formed tunneling nanotubes between these two types of cells. The transfer efficiency was greatly enhanced in the presence of CoCl2. More importantly, inhibition of tunneling nanotubes partially abrogated the beneficial effects of mesenchymal stem cells on CoCl2-induced PC12 cell injury. Mesenchymal stem cells reduced CoCl2-induced PC12 cell injury and these effects were in part due to efficacious mitochondrial transfer.

Context: Calenduloside E (CE), one of the primary natural products found in Aralia elata (Miq.) Seem. (Araliaceae), possesses prominent anti-apoptotic potential. A previous study found that one of the anti-apoptotic CE targets is heat shock protein 90 AB1 (Hsp90AB1) by probe CE-P, while the other targets of CE still need to be identified with more efficient probes. Objective: This study investigates CE analogue (CEA) as one clickable activity-based probe for use in exploring anti-apoptotic CE targets. Materials and methods: Pretreatment of HUVECs with CEA (1.25 μM) for 8 hr, followed by ox-LDL stimulation for 24 h. Flow cytometry analysis and JC-1 staining assays were performed The kinetic constant measurements were tested by the Biacore T200, CM5 Sensor Chip which was activated by using sulpho-NHS/EDC. Ligands were dissolved and injected with a concentration of 12.5, 6.25, 3.125, 1.56, 0.78 and 0 μM. Results: CEA was confirmed to possess an anti-apoptotic effect. The probable targets of CE/CEA were calculated, and as one of the higher scores proteins (Fit values: 0.88/0.86), Hsp90 properly got our attention. Molecular modelling study showed that both CE and CEA could bind to Hsp90 with the similar interaction, and the docking scores (S value) were −7.61 and −7.33. SPR assay provided more evidence to prove that CEA can interact with Hsp90 with the KD value 11.7 µM. Discussion and conclusions: Our results suggest that clickable probe CEA could alleviate ox-LDL induced apoptosis by a similar mechanism of anti-apoptotic CE, and afforded the possibility of identifying additional anti-apoptotic targets of CE.

Rheumatoid arthritis (RA) is a common chronic autoimmune disease featured by synovial inflammation. miR-496 is closely involved in various pathologic conditions. However, its role in RA has not yet been elucidated. Expression of miR-496 and MMP10 was determined based on the clinical samples with RA retrieved from the Gene Expression Omnibus (GEO) datasets. In vitro model of RA was constructed in MH7A cells stimulated by IL-1β (10 ng/mL). Cell counting kit 8 (CCK-8) and flow cytometry experiments were implemented to investigate the cell viability and apoptosis rate of MH7A cells. TargetScan was applied to identify the targets of miR-496, and the regulation of miR-496 on MMP10 expression was validated by a dual-luciferase reporter gene assay. qRT-PCR and western blot analyses were conducted to examine the expression. miR-496 expression was decreased in RA tissues and MH7A cells after IL-1β treatment. Overexpression of miR-496 significantly inhibited IL-1β-treated MH7A cell viability. MMP10 was identified as a target of miR-496 and its expression was negatively regulated by miR-496. The effects of miR-496 on MH7A cell proliferation and apoptosis were reversed by MMP10. The activity of NF-κB pathway was associated with the miR-496/MMP10 axis in IL-1β-stimulated MH7A cells. To summarize, this study demonstrated that miR-496 can impair the proliferative ability and facilitate the apoptosis of IL-1β-treated MH7A through regulating MMP10 expression and NF-κB signaling pathway.

African swine fever is caused by African swine fever virus (ASFV), and has a mortality rate approaching 100%. It has already caused tremendous economy lost around the world. Without effective vaccine, rapid and accurate on-site detection plays an indispensable role in controlling outbreaks. Herein, by combining Hive-Chip and direct loop-mediated isothermal amplification (LAMP), we establish a multiplex and visual detection platform. LAMP primers targeting five ASFV genes (B646L, B962L, C717R, D1133L, and G1340L) were designed and pre-fixed in Hive-Chip. On-chip LAMP showed the limits of detection (LOD) of ASFV synthetic DNAs and mock samples are 30 and 50 copies per microliter, respectively, and there is no cross-reaction among the target genes. The overall performance of our platform is comparable to that of the commercial kits. From sample preparation to results readout, the entire process takes less than 70 min. Multiplex detection of real samples of ASFV and other swine viruses further demonstrates the high sensitivity and specificity of Hive-Chip. Overall, our platform provides a promising option for on-site, fast and accurate detection of ASFV., Graphical abstract Image 1, Highlights • Hive-Chip firstly realized simultaneous detection of multiple genes of ASFV, largely avoiding false-negative results. • Without nucleic acid extraction, direct LAMP was firstly incorporated into the Hive-Chip for visual detection. • Because very little operation and no complicate instrument is required, on-site detection is possible for this platform.

Background: We recently developed a liposomal nanoparticle system that can be used for drug delivery and simultaneously be monitored by optical or photoacoustic imaging devices. Here we tested the efficacy of alendronate as a homing molecule in SM-liposomes for bone targeting. Methods: Alendronate was immobilized covalently on the liposomal surface and the fluorescent dye indocyanine green was used as a payload in the liposomes. The indocyanine green delivery was analyzed by 3D optical tomography, optical fluorescence scanner, photoacoustic imaging, and by ex-vivo biodistribution studies. Results: The results show that the alendronate, coupled to the liposomal surface, increases sphingomyelin containing liposome targeting up to several-folds. Conclusion: The alendronate targeted liposomes open possibilities for an application in active bone targeting.

This study examined the course of mitophagy following cerebral ischemia with reperfusion and the role of the PTEN-induced kinase 1 (PINK1)/Parkin/p62 signalling pathway. The middle cerebral artery of male Sprague-Dawley rats was occluded for 90 min and was followed by different time-points of reperfusion. Cerebral infarct areas were detected by 2,3,5-triphenyl tetrazolium chloride staining, while brain damage was observed by haematoxylin and eosin staining. Levels of LC3, Beclin1 and LAMP-1 were estimated by western blots. LC3B location was observed in various cells in the neurovascular unit. In addition, PINK1 accumulation in damaged mitochondria and Parkin/p62 mitochondrial translocation were investigated by double immunofluorescence staining. Finally, the levels of PINK1, Parkin and p62 expression in mitochondrial fractions were estimated by western blots. Cerebral ischemia with different time-points of reperfusion resulted in infarct in the territory of the middle cerebral artery accompanied by overall brain damage. In addition, we found up-regulation of LC3B, Beclin1, and LAMP-1, as well as mitophagy activation after reperfusion, with peak expression of these proteins at 24 h after reperfusion. Electron microscopy and immunofluorescence indicated that LC3B was primarily located in neurons, although lower levels of expression were found in astrocytes and even less in vascular endothelial cells. Moreover, significant increases in PINK1 accumulation in the outer membrane of mitochondria and increased Parkin/p62 mitochondrial translocation were shown at 24 h after reperfusion. These findings suggest that the PINK1/Parkin/p62 signalling pathway was involved in the pathophysiological processes following ischemia and reperfusion.

Aminic radical-trapping antioxidants (RTAs), as one of the most important antioxidants, have not received sufficient attention yet. But, an increasing number of aminic RTAs have been identified as ferroptosis inhibitors in recent years, which can potentially mediate many pathological states including inflammation, cancer, neurodegenerative disease, as well as ocular and kidney degeneration. This highlights the importance of aminic RTAs in the field of medicine. Herein, we systematically explored the radical scavenging mechanism of aminic RTAs with a quantum chemical method, particularly emphasizing the role of stereoelectronic factors and resonance factors on the transfer of H-atom and the stability to one-electron oxidation. These theoretical results elucidate the diversity of free radical scavenging mechanisms for aminic RTAs, and has significant implications for the rational design of new aminic RTAs.

Late Pennsylvania–Early Permian carbonate mud-mounds exposed in the Shangdan section, Inner Mongolia, are commonly massive, showing depositional relief, and are distinct from the thin- to medium-bedded limestones of intra-mounds. Based on the various proportions of lithofacies, four types of mud-mounds are recognized: MM-A (type A carbonate mud-mound) and B (type B carbonate mud-mound) consist of massive lime mudstone and massive wackestone (Subfacies B), respectively; MM-C (type C carbonate mud-mound) are composed of massive wackestone (Subfacies B) in the lower parts, analogous to MM-B, and massive wackestone (Subfacies A) and boundstone in the upper parts, similar to MM-D (type D carbonate mud-mound). Carbonate mud-mounds are deposited in low-energy settings on a ramp, likely below fair-weather wave base, where the depositional settings of MM-A, B, C and D have a shallowing-upward trend. Carbonate mud-mounds have diverse origins of lime mud: allochthonous lime mud in MM-A; lime mud produced by the disintegration of phylloid algae in MM-B, C and D; lime mud linked to cyanobacterial activity in MM-D and the upper parts of MM-C. Different from MM-A and B, which were formed only by mechanical accumulation, MM-C and D resulted from the combinations of mechanical accumulation and microbial binding and solidifying. MM-A, B, C and D significantly expand the global spectrum of Late Pennsylvania–Early Permian carbonate mounds.

The development of inert additive-doped CaO-based CO2 adsorbents is a promising method to obtain efficient CO2 adsorbents, while multiple programs are frequently involved, the organic solvent is often used, and CO2 is sometimes released in the process of preparation. In this study, we first report that inert additive-doped CaO-based adsorbents can be synthesized in one pot by the mechanochemical hydrogenation reduction of CaCO3 producing methane and avoiding CO2 emission. The prepared CaO@C and CaO@MgO@C composites are high-performance CO2 adsorbents with high CO2 adsorption capacity and superior cycling stability. The results show that the CO2 capture capacities of the CaO@C and CaO@MgO@C composites are 19.14 and 14.53 wt% higher than that of the BM-CaO (37.07 wt%), respectively, at 650 °C carbonation for 2 h. Notably, the activity losses of the CaO@C and CaO@MgO@C composites after 30 cycles are about 47.93 and 29.33%, which are much lower than that of the BM-CaO (60.39%). The performance of the CaO@C and CaO@MgO@C adsorbents is comparable to that of adsorbents synthesized by the conventional methods, but this work provides novel, simple, solution-free, and sustainable strategies to synthesize effective CaO-based CO2 adsorbents in one pot.

An asymmetric synthesis of 14-methyl-1-octadecene, the sex pheromone of the peach leafminer moth, has been efficiently achieved. A key chiral intermediate, ( R)−4-(benzyloxy)−3-methylbutanal, which has been developed as the resource chemical, can be obtained in large quantities from the steroid industry. 1,11-Undecanediol is selectively masked, and then converted into a phosphonium salt derivative, thereby effectively constructing a carbon skeleton. The target molecule is synthesized in 8 linear steps, with a 42% yield. The key characteristic of our synthesis lies in its chiral-pool strategy.

Background Isolating of primary motor neurons from animal embryos is critical for the study of neurological disease including mechanistic discovery and therapeutic development. Density gradient centrifuge taking advantage of the buoyant of motor neuron permits the enrichment of motor neurons. Despite the metrizamide, an OptiPrep medium has been introduced to separate the motor neurons by gradient centrifuge. New method We hereby used single density gradient of OptiPrep medium to isolate the spinal motor neurons from the fetal mouse. Results Single density gradient of OptiPrep medium is effective to isolate spinal motor neurons from the fetal mouse. The immunofluorescence staining analysis showed that the purity of cultured motor neurons at 72 h was between 90% and 95%. Comparison with existing method Four gradients of OptiPrep medium have been previously used to isolate the motor neurons from spinal cord of mouse. In this study, the single gradient of OptiPrep medium was demonstrated to effectively isolate spinal motor neurons from the fetal mouse. Conclusions The single gradient of OptiPrep medium is enough to produce high purity of spinal motor neurons from the fetal mouse.

9 batches of unconfined methane-air deflagration tests were conducted to investigate the influential factors on the deflagration load. The methane-air mixture was filled in the cubic tents with different volumes of 1 m3, 8 m3and 27 m3. Methane concentrations varied from 7.5% to 11.5%, covering both lean and rich combustion regimes. The ground overpressure was recorded by using the piezoresistive sensors. An ideal film was validated before the tests. The effects of the methane concentration and gas volume on the deflagration load were analyzed. Based on the results, a new prediction model for the unconfined methane-air deflagration load was proposed. In addition, the model was compared with some existing models.

To investigate the effect of doping defects on properties of pentaerythritol tetranitrate (PETN), the “perfect” and doping defective crystal models of PETN containing pentaerythritol (PE), pentaerythritol mononitrate (PEMonoN), pentaerythritol dinitrate (PEDiN), and pentaerythritol trinitrate (PETRIN) were established, respectively. Molecular dynamics (MD) method was applied to perform simulations, and sensitivity, detonation performance, and mechanical properties were calculated and compared. The results indicate that compared with PETN (1 1 0) supercell model, the interaction energy of trigger bond and cohesive energy density of the doped defect models decreased by 2.21~12.43 kJ mol−1 and 0.0219~0.0421 kJ cm−3, respectively, indicating that the sensitivity of defective models increases and the safety decreases. The density, detonation velocity, and detonation pressure of the doped defect model decreased by 0.018~0.061 g cm−3, 77.833~272.809 m s−1, and 0.746~2.544 GPa, respectively, and the oxygen balance is declined, indicating that the energy density of PETN decreased and the power decreased. Doped defects also cause the elastic modulus, bulk modulus, and shear modulus of PETN to decrease by 0.75~2.16 GPa, 0.44~0.89 GPa, and 0.30~0.89 GPa, respectively. The ratio of bulk modulus to shear modulus and Cauchy pressure increased by 0.05~0.28 GPa and 0.09~1.13 GPa, respectively, indicating that the deformation resistance, fracture strength, and hardness of the doped defect model decrease, stiffness decreases, and flexibility and ductility increase.

The production of pneumocandin B0 is limited by feedback inhibition. Here, low-temperature adaptive laboratory evolution (ALE) was used to improve the production capacity of Glarea lozoyensis by enhancing its membrane permeability. After 50 cycles of ALE, the pneumocandin B0 production of the endpoint strain (ALE50) reached 2131 g/L, which was 32% higher than the starting strain (ALE0). ALE50 showed a changed fatty acid composition of the cell membrane, which-+h increased its permeability by 14%, which in turn increased the secretion ratio threefold. Furthermore, ALE50 showed increased intracellular proline and acetyl-CoA concentrations, superoxide dismutase (SOD), and catalase (CAT) activity, as well as total antioxidant capacity. The slight biomass decrease in ALE50 was accompanied by decreased isocitrate dehydrogenase (ICDH) and glucose-6-phosphate dehydrogenase (G6PDH) activity. Finally, a putative model of the accumulation and secretion of pneumocandin B0 in ALE50 was established. ALE is a promising method to release intracellular feedback inhibition.

Pleurotus tuoliensis is a valuable, rare and edible mushroom that is been commercially cultivated and is rapidly developing in China markets. Low temperatures are required to induces primordia initiation for the successful production of fruiting bodies (basidiomes) during commercial cultivation. In this work, we investigated the enzymatic activities and performed transcription profiling analysis of enzymatic genes under different low temperature conditions. The results suggest that the enzymatic activities and transcription levels decrease or increase significantly at 4 and 13 °C. Lacc10 and mnp6 seems to play a dominant role during nutrition growth. Furthermore, the expression of laccase and peroxidase genes was highly correlated to the detected extracellular enzymatic activity. Cold stress genes expression profiles were upregulated under 4 °C/13 °C (3 days), while only the Hsp70 gene was downregulated (at the stage of fruiting bodies production) at 13 °C (12 days). Our results showed that the transcriptional regulation of laccase and ligninolytic peroxidase genes plays an important role in the fruiting bodies of Bailinggu under low temperature induction (4 °C). Induction at low temperatures was a highly important cultivation condition in Bailinggu.

The formation of urea linkages is a limitation to the application of solid amine CO2 adsorbents. Therefore, the development of solid amine adsorbents with resistance to urea linkage formation has attracted much interest over the last 5 years. In this study, we developed a facile method for synthesizing solid amine adsorbents with effective resistance to urea linkage formation. For the first time, metal nitrates were used to modify amorphous nano SiO2 to support polyethyleneimine (PEI). Three metal nitrates were investigated: aluminum, magnesium, and zinc nitrates. A series of adsorbents were prepared by controlling the mass ratios of metal nitrates and nano SiO2. After 50 cycles of adsorption–desorption tests, adsorbing at 75 °C under 15 % CO2 balanced with N2 and desorbing at 130 °C under pure CO2, Al-20%@SiO2-PEI, Al-15%@SiO2-PEI, Al-10%@SiO2-PEI, Zn-10%@SiO2-PEI, and Mg-10%@SiO2-PEI lost only 2.6 %, 4.0 %, 5.2 %, 15.9 %, and 28.8 % of their original CO2 adsorption capacities, respectively. However, SiO2-PEI, calcined SiO2-PEI, and Al-5%@SiO2-PEI lost 42.9 %, 48.6 %, and 49.6 %, respectively. By combining the infrared spectra of all the adsorbents through cyclic adsorption–desorption tests, inhibitory effects on urea linkage formation were proven for Al-20%@SiO2-PEI, Al-15%@SiO2-PEI, Zn-10%@SiO2-PEI, and Mg-10%@SiO2-PEI, and especially for Al-10%@SiO2-PEI. Through a relatively comprehensive analysis, we found that a desirable amount of metal nitrates could modify nano SiO2 samples and their corresponding adsorbents possessed a stronger H2O binding ability at 130 °C. The retained H2O could act as an inhibiting agent for the inhibition of urea linkage formation.

First principles calculation is performed to study the co-adsorption behaviors of O2 and CO2 on δ-Pu(100) surface by using a slab model within the framework of density functional theory (DFT). The results demonstrate that the most favorable co-adsorption configurations are Tv-C4O7 and Tp1-C2O8, with adsorption energy of –17.296 eV and –23.131 eV for CO2-based and O2-based system, respectively. The C and O atoms mainly interact with the Pu surface atoms. Furthermore, the chemical bonding between C/O and Pu atom is mainly of ionic state, and the reaction mechanism is that C 2s, C 2p, O 2s, and O 2p orbitals overlap and hybridize with Pu 6p, Pu 6d, and Pu 5f orbital, resulting in the occurrence of new band structure. The adsorption and dissociation of CO2 molecule are obviously promoted by preferentially occupying adsorbed O atoms, therefore, a potential CO2 protection mechanism for plutonium-based materials is that in CO2 molecule there occurs complete dissociation of CO2 → C + O + O, then the dissociated C atom combines with O atom from O2 dissociation and produces CO, which will inhibit the O2 from further oxidizing Pu surface, and slow down the corrosion rate of plutonium-based materials.

29 batches of vented explosion tests were conducted in a 12 m 3 concrete chamber filled with methane–air mixtures to investigate the effects of methane concentration and venting pressure on the development of overpressure inside the chamber. The deflagrations were vented from a square side window with a venting area of 0.64 m 2 upon rupture of the vent cover. The venting pressures were varied by using six different types of vent covers, and determined by performing a numerical simulation. Methane concentrations in the mixed gas varied between 6.5 and 13.5 vol.%, covering both lean and rich combustion regimes. The generation conditions of the four types of overpressure–time profiles with different overpressure transients were summarized. Among the overpressure transients, the Δ P 1 caused by failure of the vent cover and the Δ P 4 resulted from the coupling between acoustic mode and flame were basically dominant. The rate of Δ P 1 rise as well as peak value of Δ P 1 and Δ P 4 showed a same trend of first increasing and then decreasing with the methane concentration from lean to rich. They reached their maximum value at the methane concentration of about 9.5%, whereas the rate of Δ P 4 rise was found to be insensitive to the methane concentration. The peak value of Δ P 1 increased with the venting pressure, while that of Δ P 4 first increased and then decreased as the venting pressure increased. In addition, the rates of Δ P 1 and Δ P 4 rise were both insensitive to the venting pressure. The occurrence of Δ P 4 was depended on the methane concentration and the venting pressure. The differences in the behavior of these overpressure transients suggest their different generation mechanisms.

Modulation of apoptosis is therapeutically effective in cardiomyocytes damage. Calenduloside E (CE), a naturally occurring triterpenoid saponin, is a potent anti-apoptotic agent. However, little is known about its synthetic analogues on the protective effects in apoptosis of cardiomyocytes. The present research was performed to investigate the potential protective effect of CE analogues against H2O2-induced apoptosis in H9c2 cardiomyocytes and the underlying mechanisms. Sixteen novel CE anologues have been designed, synthesized and biological evaluation. Among the 16 CE anologues, as well as the positive control CE tested, compound 5d was the most effective in improving cardiomyocytes viability. Pretreatment with anologue 5d inhibited ROS generation, maintained the mitochondrial membrane potential and reduced apoptotic cardiomyocytes. Moreover, exposure to H2O2 significantly increased the levels of Bax, cleaved caspase-3, and cleaved PARP, and decreased the level of Bcl-2, resulting in cell apoptosis. Pretreatment with anologue 5d (0.02–0.5 μg/mL) dose-dependently upregulated antiapoptotic proteins and downregulated proapoptotic proteins mentioned above during H2O2-induced apoptosis. These results suggested that CE analogues provide protection to H9c2 cardiomyocytes against H2O2-induced oxidative stress and apoptosis, most likely via anti-apoptotic mechanism, and provided the basis for the further optimization of the CE analogues.

Rhubarb is commonly used as laxatives in Asian countries, of which anthraquinones are the major active ingredients, but there are an increased number of concerns regarding the nephrotoxicity of anthraquinones. In this study, we compared the pharmacokinetic characteristics of rhubarb anthraquinones in rats after orally administered with rhubarb and rhubarb total free anthraquinone oral colon-specific drug delivery granules (RTFA-OCDD-GN), and then explained why these granules could reduce the nephrotoxicity of anthraquinones when they produced purgative efficacy. A sensitive and reliable high performance liquid chromatography (HPLC) method has been fully validated for simultaneous determination of the five active components of rhubarb, and successfully applied to investigate and compare the remarkable differences in pharmacokinetic study of rhubarb anthraquinones after orally administered with rhubarb and RTFA-OCDD-GN. The results showed that, compared with rhubarb group, the AUC, Cmax, t1/2z and Vz/F of aloe-emodin, rhein, emodin and chrysophanol in rats receiving the RTFA-OCDD-GN were significantly decreased, and the Tmax of the four analytes was prolonged. Moreover, the Tmax of rhein, the Cmax of chrysophanol and emodin all have significant differences (P

The effects of different proportions of poly (vinyl alcohol) and polyamide 6 on the structure and property of electrospun PA6/PVA membranes have been studied. According to a certain proportion, PVA and PA6 were dissolved in formic acid. The solution was electrospun at 70 kV. The nanofibers membranes were characterized by SEM, FT-IR, XRD, TGA and DSC analyses. The sound absorption coefficients of each absorber are measured with SW477 impedance tube. PA6/PVA composite mats with good compatibility and relatively stable performance, and enhanced sound absorption and property may have many other important applications.

Objective: To explore the effects of the biodegradability of biomaterial scaffolds on skin tissue regeneration and its neovascularization by the animal experiments. Methods: A piece of porous silk fibroin film (SF) of easy biodegradation and a piece of porous polyvinyl alcohol film (PVA) of hard biodegradation were implanted into a same skin wound of adult rat, and the differences in the regenerative blood vessel and tissue at 5, 10, 16, 41 days after surgery were observed by histological methods. Results: (1) at 10 days after surgery, the SF started to degrade, the closed areas without cell infiltration were opened up and the entire material was filled with the regenerative tissue, and there were still the closed areas in the PVA, (2) the new vascular network remodeling in the SF and PVA appeared at 10 days and 41 days after surgery, respectively, and (3) at 16 days after surgery, most of the SF material had degraded and substantially been replaced with the regenerative tissue, and the visible degradation of the PVA appeared at 41 days after surgery. Conclusion: The good biodegradability of the SF was helpful both to all vascularization of the material and to the regenerative blood vessels remodeling, and the regenerative tissue was closer to the normal dermal tissue than in the PVA.

Hydrogels had been prepared by blending four types of surfactants such as alkyl betaine (zwitterion surfactant), tween 60 (non-ionic surfactant), sodium fatty alcohol ether sulfate (anionic surfactant) and silicone quaternary ammonium salt (cationic surfactant) with bombyx mori silk fibroin (SF) solution. Surfactant molecules would interact with SF molecules, resulting in lower critical micelle concentration (CMC). Gelation time measurements showed surfactants had significantly accelerated the hydrogelation process of SF solution, which could be controlled by the type or blend ratio of surfactants. Fourier transform infrared (FTIR) indicated that the addition of surfactants affected the molecular secondary of SF. The results from X-ray diffraction indicated that surfactants and SF were only blended but phase separation with two kinds of crystalline structure. SEM images showed that the surfactants had significantly changed the morphology of hydrogels according to certain rules, especially non-ionic and cationic surfactants could induce silk fibroin solutions into porous and nanofibrous hydrogels. These results indicated that a novel and potential method not only can be used to accelerate hydrogelation process of SF solution but also can be used to alter the structural and morphological of SF hydrogels. Furthermore, the porous and nanofibrous hydrogels of SF induced by surfactants provided a novel strategy to mimic the nanofibrous structure of collagen in extracellular matrix (ECM).

Cadmium (Cd) and tetrabromobisphenol A (TBBPA) are two prevalent contaminants in e-waste recycling facilities. However, the potential adversely health effect of co-exposure to these two types of pollutants in an occupational setting is unknown. In this study, we investigated co-exposure of these two pollutants on hepatic toxicity in CD-1 male mice through a whole-body aerosol inhalation route. Specifically, mice were exposed to solvent control (5% DMSO), Cd (8μg/m(3)), TBBPA (16μg/m(3)) and Cd/TBBPA mixture for 8h/day and 6days a week for 60 days. Hepatic changes include increased organ weight, focal necrosis, and elevated levels of liver enzymes in serum. These changes were most severe in mice exposed to TBBPA, followed by Cd/TBBPA mixture and Cd. These chemicals also led to suppressed antioxidant defensive mechanisms and increased oxidative stress. Further, these chemicals induced gene expression of apoptosis-related genes, activated genes encoding for phase I detoxification enzymes and inhibited genes encoding for phase II detoxification enzymes. These findings indicate that the hepatic damages induced by subchronic aerosol exposure of Cd and TBBPA may result from the oxidative damages caused by excessive ROS production when these chemicals were metabolized in the liver.

In this paper, we employed Methanol, 75% Ethanol, 100%Ethanol, and Isopropanol to treat electrospun SF nanofiber mats, and studied the morphology, structure and property of SF nanofiber before and after treatment by means of SEM, and FTIR. While the as-spun SF nanofiber mats consisted of α-helix and random coil, post-treatment of the SF nanofiber resulted in significant increase in β-sheet component and improvement of water resistance of the SF nanofiber mats. This effect was not obvious affected when different post-treatment system was used, but methanol and 75% was more effective in inducing conformation transition from α-helix and random coil to β-sheet.

The silk fibroin/sodium alginate scaffolds were prepared using lyophilization method. And then, the blend scaffolds were treated with calcium ions. The morphology of the blend scaffolds exhibited a thin layer structure before calcium ions treatment, and much more rod-like structure appeared at the layer surface with adding the increase content of sodium alginate in the blend scaffolds. After calcium ions treatment, much more rod-like structure disappeared after adding 30% sodium alginate or more in the blend scaffolds. Wide angle X-ray diffraction and Fourier transform infrared analysis results confirmed the crystal structure of silk fibroin was not influenced by adding the different content of sodium alginate, exhibiting the silk I and silk II structure co-existed in the blend scaffolds. And the same time, the average mass loss value of the blend scaffolds was higher than the pure silk fibroin scaffold, reaching 9.884%, 11.2%, and 8.626%, respectively, when the blend scaffolds contained 10%, 30%, and 50% sodium alginate, respectively. Thus, the silk fibroin/sodium alginate scaffolds should be a useful biomaterial applicable for a wide range of tissue engineering.

More and more attention has been paid to natural materials. This paper was carried out with an intention to investigate the effect of electrospun silk fibroin (SF) nanofibrous mats by mixing different weight raito of chitosan (CS) in the same solvent-formic acid. Based on good electrospining feasibility, it was found that the average diameter of spun fibers became fine from 337nm to 103nm, with the concentration of CS in the blend compositions increasing to 4%.At the same time, the conformational transition of SF nanofibers adding CS occured to the tendence towards β-sheet structure by means of the analysis of the Fourier transform infrared spectroscopy (FTIR), Wide angle X-ray diffraction (WAXD) and Differential thermal analysis (TGA).What was more, excellent antibacterial activity(a degree growth inhibition of more than 95%) of the promising nanofibrous mats was revealed, through utilizing the colony counting method against Gram-positive bacteria S. aureus and Gram-negative bacteria E.coli ,which would open up wide applications on would dressing, filtration and environmental purification.

Polyethylene Glycol Oleate was synthesized by esterification of polyethylene glycol and Oil acid using DMAP as a catalyst. The double bonds of the product in the core of micelles were cross-linked by the initiation of (NH4)2S2O8 during the micelles formed. Applications of the noncross-linked and cross-linked polyethylene glycol oleate in drug delivery were studied, which indicates that drug efficiency decreased after micelles were core cross-linked, but release rate of MTX from core cross-linked micelles seems slower than that from noncross-linked micelles.

To improve damage tolerance performance, GLARE was used as bonded crack retarders in this paper. Fatigue tests were run with unbonded and bonded samples; then test results between them was compared. Thermal residual stresses had been studied. It was found that bonded crack retarders can improve damage tolerance performance and capability. Thermal residual stresses have a detrimental effect on the fatigue crack growth rates by means of increasing the effective R-ratio applied on the aluminium substrate. Finite element analysis was carried out and the result was in good agreement with the experimental data.

Electrospun Silk-Fibroin (SF) mats were fabricated by electrospinning with regenerated Bombyx mori silk-fibroin/formic acid solutions. After spinning, the water soluble and mechanical properties of pure fibroin nanofibers were poor. So electrospun SF mats were crosslinked with N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC), a low cell cytotoxicity crosslinking agent, and N-hydroxysuccinimide (NHS), which can increase the reaction rate. The scanning electron microscope images indicated that the diameter of fibers increased with crosslinking reaction. When EDC/NHS reached to 7.5wt.%, the diameter of fibers achieved the maximum. The mechanical test showed that tensile strength enhanced after crosslinking with EDC/ NHS. While EDC/NHS reached to 7.5wt %, the rupture strength reached to (38.31±5.30) Mpa, and the breaking elongation ratio reached to (182.00±31.27) %. FTIR results showed the the proportion of β-sheet increased while random coil and α-helix decreased after treatment.

A series of novel oleanolic acid 3-O-β-d-glucuronopyranoside derivatives have been designed and synthesized. Biological evaluation has indicated that some of the synthesized compounds exhibit moderate to good activity against H2O2-induced injury in rat myocardial cells (H9c2). Particularly, derivative 28-N-isobutyl ursolic amide 3-O-β-d-galactopyranoside (8a) exhibited a greater protective effect than the positive control oleanolic acid 3-O-β-d-glucuronopyranoside, indicating that it possesses a great potential for further development as a cardiovascular disease modulator by structural modification.

To study DNA methylation polymorphism in soybean, 20 and 27 lines of annual wild and cultivated soybeans, respectively, were selected from previously established “Soybean Core Collections in China”, and subjected to methylation-sensitive amplified polymorphism (MSAP) analysis. Twenty-seven primer pairs generated 984 CG/CNG methylation sites across the 47 lines, and the data were dissected into methylation-sensitive (MS) and methylation-insensitive(MIS) polymorphisms. The calculated MSP vs. MISP for wild soybeans were 34.65 vs. 34.76%, while corresponding results for the cultivated soybeans were 47.05 vs. 47.15%, indicating higher levels of MSP and MISP in cultivated than in wild soybeans. These results were incongruent with the amplified fragment length polymorphism (AFLP) analysis of the same soybean lines, and suggested enhanced DNA methylation polymorphism due to human selection. All three markers, MSP, MISP and AFLP, enabled clustering of the soybean lines into two distinct groups each predominantly containing wild or cultivated ones. Homology search indicated that 12 out of 24 sequenced MSPs had significant similarities to known-function or predicated genes, suggesting possible functional relevance of the methylation polymorphism. No significant association between MSP and MISP or MSP and AFLP was detected. Our results suggest that DNA methylation polymorphism in soybean has been under both natural and human selections, implicating possible roles of this epigenetic modification in genome evolution and domestication.Key words: Annual wild soybean (Glycine soja), cultivated soybean (G. max), DNA methylation polymorphism, epigenetic variation, evolution, domestication

Seed vigor is a more promising seed quality character reflecting potential seed germination, field emergence and seed storage ability under different conditions than standard germination. Standard germination is influenced by genetic background and environmental effects during seed development and storage conditions. The latest research on physiological mechanism in seed vigor showed that at the late stage of seed development, the development of seed vigor involves some stress-resistant substances including late embryogenesis abundant (LEA) protein, oligosaccharides and abscisic acid (ABA). Whereas the loss of seed vigor, or seed aging and deterioration, could be attributed to lipid peroxidation, chromosome deformation and genes aberrance, and embryo protein degradation, etc. Seed vigor is a quantitative character controlled by multi-genes. Genetic and quantitative trait locus (QTL) analyses on seed-vigor trait in model plants, such as Arabidopsis and rice, are mostly concentrated on related morphology traits, whereas few physiological traits have been researched. It was concluded that, all of the QTL genetic characteristics of seed vigorincluding QTL quantities, its locus on chromosome, genetic effects, and interaction effects between genetic and environment, differed with plant species and used seed-vigor traits.

Telomere and telomerase were closely related to occurrence and development of some cancers. To enhance ability of myricetin moiety for inhibiting telomerase, we designed a series of novel myricetin derivatives based on reasonable analysis. The telomerase inhibition assay showed that compound 6d displayed the most potent inhibitory activity with IC50 value of 0.91 μM. The anticancer activity assay showed that 6d exhibited high activity against human breast cells MDA-MB-231. The docking simulation of compound 6d was performed to get the probable binding model, the results demonstrated that the furan ring inserted into the active site deeply and had hydrophobic interactions with residues of Phe 568, Pro 627, four methoxy groups had hydrophobic interactions with residues of Phe 568, Pro 627, Lys 902, Val 904 and Pro 929. Western blot results showed that expression of p65 and TERT protein was clearly down-regulated by compound 6d. These data support further studies for the rational design of more efficient p65 and TERT modulators.

Isoquercitrin is a rare, natural ingredient with several biological activities that is a key precursor for the synthesis of enzymatically modified isoquercitrin (EMIQ). The enzymatic production of isoquercitrin from rutin catalyzed by hesperidinase is feasible; however, the bioprocess is hindered by low substrate concentration and a long reaction time. Thus, a novel biphase system consisting of [Bmim][BF4]:glycine-sodium hydroxide (pH 9) (10:90, v/v) and glyceryl triacetate (1:1, v/v) was initially established for isoquercitrin production. The biotransformation product was identified using liquid chromatography-mass spectrometry and the bonding mechanism of the enzyme and substrate was inferred using circular dichroism spectra and kinetic parameters. The highest rutin conversion of 99.5% and isoquercitrin yield of 93.9% were obtained after 3 h. The reaction route is environmentally benign and mild and the biphase system could be reused. The substrate concentration was increased 2.6-fold, the reaction time was reduced to three tenths the original time. The three-dimensional structure of hesperidinase was changed in the biphase system, which α-helix and random content were reduced and β-sheet content was increased. Thus, the developed biphase system can effectively strengthen the hesperidinase-catalyzed synthesis of isoquercitrin with high yield.

A new spheroidizing process of ultra-high carbon steel (UHCS) containing C 1.55%, Cr 1.45%, and Al 1.5% in mass percent has been proposed. The effect of processing parameters on the microstructure was analyzed. The UHCS produced by this new process has a microstructure with recrystallized ferrite matrix and fine and uniform carbide particles. After this spheroidizing, the UHCS exhibits good mechanical properties at ambient temperature, for example σ b =1 100 MPa, σ s = 915 MPa, δ=8% and high ratio of σ s /σ b .

A series of novel pyrazole-5-carboxamide and pyrazole-pyrimidine derivatives were designed and synthesized. All compounds have been screened for their antiproliferative activity against MGC-803, SGC-7901 and Bcap-37 cell lines in vitro. The results revealed that compounds 8a, 8c and 8e exhibited strong inhibitory activity against MGC-803 cell line. The flow cytometric analysis result showed that compound 8e could inhibit MGC-803 proliferation. Some title compounds were tested against telomerase, and compound 8e showed the most potent inhibitory activity with IC50 value at 1.02 ± 0.08 μM. The docking simulation of compound 8e was performed to get the probable binding model, among them, LYS 189, LYS 372, LYS 249 and ASP 254 may be the key residues for the telomerase activity.

A series of novel 5-phenyl-N-piperidine ethanone-4,5-dihydropyrazole derivatives as potential telomerase inhibitors were synthesized. The bioassays demonstrated that compounds 4d, 4f, 7a and 7b occupied high antiproliferative activities against SGC-7901, MGC-803 and Bcap-37 cell lines. By a modified TRAP assay, some titled compounds were tested against telomerase, and compound 7b showed the most potent inhibitory activity with IC50 value at 2.00 ± 0.40 μM. The active compound 4d was also docked into the telomerase TERT active site to determine the probable binding model. The results indicated that conserved residues Lys189, Asp254 and Gln308 were important for ligand binding via hydrogen bond interactions.

A series of novel N-phenylacetyl (sulfonyl) 4,5-dihydropyrazole derivatives as potential telomerase inhibitors were synthesized. The bioassay tests show that compound 4a exhibited high activity against human gastric cancer cell SGC-7901, liver cancer Hep-G2 and human prostate PC-3 cell lines with IC50 values of 21.23 ± 0.99, 29.43 ± 0.32 and 30.89 ± 1.07 μM, respectively. All title compounds were assayed for telomerase inhibition by a modified TRAP assay, the results show that compound 4a can inhibit telomerase with IC50 value of 4.0 ± 0.32 μM. Docking simulation was performed to position compound 4a into the telomerase ( 3DU6 ) active site to determine the probable binding model.

A series of novel coumarin derivatives containing 4,5-dihydropyrazole moiety as potential telomerase inhibitors were synthesized. The bioassay tests show that compound 3d exhibited potentially high activity against human gastric cancer cell SGC-7901 with IC(50) value of 2.69 ± 0.60 μg/mL. All title compounds were assayed for telomerase inhibition by a modified TRAP assay, the results show that compounds 3d and 3f can strongly inhibit telomerase with IC(50) values of 2.0 ± 0.07 and 1.8 ± 0.35 μM, respectively. Docking simulation was performed to position compound 3d into the telomerase (3DU6) active site to determine the probable binding model.

A series of novel 2-chloro-pyridine derivatives containing flavone, chrome or dihydropyrazole moieties as potential telomerase inhibitors were synthesized. The bioassay tests showed that compounds 6e and 6f exhibited some effect against gastric cancer cell SGC-7901 with IC(50) values of 22.28+/-6.26 and 18.45+/-2.79 microg/mL, respectively. All title compounds were assayed for telomerase inhibition by a modified TRAP assay, the results showed that compound 6e can strongly inhibit telomerase with IC(50) value of 0.8+/-0.07 microM. Docking simulation was performed to position compound 6e into the active site of telomerase (3DU6) to determine the probable binding model.