One of the crucial issues in rechargeable zinc-air batteries is to explore low-cost, highly efficient bifunctional electrocatalysts for the oxygen reduction/evolution reaction. Here, the unique NiCo ...alloy nanoparticles encapsulated in the multi-dimensional nitrogen-doped carbon architecture (NiCo/MNC) is reported as an effective bifunctional catalyst for rechargeable zinc-air batteries. The multi-dimensional nitrogen-doped carbon architecture was synthesized through the rapid calcination of two-dimensional graphitic carbon nitride (g-C3N4) and one-dimensional multi-walled carbon nanotubes (MWCNTs). The g-C3N4 serves as the nitrogen source and the precursor for N-doped carbon nanosheets (NCSs). Simultaneously, NCSs can intertwine with MWCNTs to further obtain the multi-dimensional architecture with a large specific surface area. The synergistic effect between multi-dimensional nitrogen-doped carbon architectures and NiCo alloy nanoparticles endowed the NiCo/MNC with a positive half-wave potential of 0.83 V (vs. RHE: Reversible Hydrogen Electrode) for oxygen reduction reaction and a low potential of 1.61 V (vs. RHE) at the current density of 10 mA cm−2 for oxygen evolution reaction. Moreover, the zinc-air battery assembled with NiCo/MNC as the air-cathode exhibited a high-power density of 135.2 mW cm−2, a specific capacity of 701.7 mAh g−1, and an excellent stability in charging/discharging cycle test (over 115 h). The prepared catalyst could potentially serve to take the place of precious metal catalysts in rechargeable zinc-air batteries.
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•NiCo alloy nanoparticles encapsulated in the multi-dimensional N-doped carbon (MNC) architecture was designed.•The synergistic effect between MNC and NiCo alloy nanoparticles can facilitate ORR/OER activities.•NiCo/MNC serves as an efficient ORR/OER catalyst for rechargeable zinc−air batteries.
Microglia are the resident immune cells in the central nervous system (CNS). After traumatic spinal cord injury (SCI), microglia undergo activation, proliferation, and changes in gene and protein ...expression and morphology, with detrimental and beneficial effects. Activated microglia cause secondary neuronal injury
the production of proinflammatory cytokines, reactive oxygen species, and proteases. However, activated microglia also promote neuronal repair through the secretion of anti-inflammatory growth factors and cytokines. Proinflammatory cytokines increase endothelial permeability, promote A1 astrocyte activation and axonal demyelination, and reduce neural stem/progenitor cells (NSPCs), leading to the exacerbation of neuronal injury. In contrast, anti-inflammatory factors facilitate angiogenesis, reduce reactive astrocytes, and promote axonal remyelination and the propagation of NSPCs, contributing to tissue repair and locomotor recovery. Due to its limited regenerative capacity, the CNS requires beneficial microglia for continuous protection against injury. Understanding and regulating microglial activation status are beneficial to reducing detrimental effects and promoting repair behaviors and to obtain more information on efficient therapies for traumatic SCI. This review discusses microglial activation and the differences between microglia and similar immune cells, microglial interactions with other cells in the spinal cord, and the progress in the development of therapies targeting microglia in SCI.
In this article, a novel digital dual-loop interleaving control algorithm is proposed for an asymmetric multiphase buck converter to further enhance the transient response under the large load step ...and ultrafast slew rate. The proposed dual loop consists of a novel nonlinear average current loop and a digital integration constant on -time (DICOT) controlled voltage loop, which are interleaving connected. The normal phases with average current control aim to deliver the majority of power, while the auxiliary phases with DICOT control are designed to regulate the output voltage and for the fast transient response. With the interleaving control approach, the average inductor current of auxiliary phases remains unchanged in a steady state under different load conditions and that of normal phases follows the load current level. Compared to existing researches, the proposed digital dual-loop interleaving control has robust operation in auxiliary phases and flexibility control of normal and auxiliary phases, as well as the simple hardware implementation. The proposed algorithm is constructed in field-programmable gate array and is applied on the eight phases asymmetric buck system, the maximum load step of 250 A with the current slew rate of 1200 A/μs is tested, the undershoot and overshoot are 30 and 41 mV respectively, and the recovery times are around 20 μs.
A flame retardant additive, aluminum poly-hexamethylenephosphinate (APHP) with a polymeric structure was synthesized from 1,5-hexadiene, hypophosphorous acid and aluminum ions. The molecular ...structure of APHP and thermal stability were characterized by solid nuclear magnetic resonance, Fourier transform infrared and thermogravimetric analysis. Then, APHP was applied into diglycidyl ether of bisphenol-A cured by 4,4′-diamino-diphenylmethane. APHP showed flame-retardant effect on the epoxy thermosets in limited oxygen index (LOI), UL94 vertical test and cone calorimeter. The thermosets with only 4 wt.% APHP obtained an LOI value of 32.7% and reached the UL94 V-1 rating. The APHP/EP thermosets decreased the pk-HRR, THR and av-EHC values, decreased CO2Y and enhanced the COY ratios, and also reserved more residual char comparing with neat thermoset. The less incorporation of APHP in thermosets will impose the better flame retardancy to epoxy thermosets. The flame-retardant effect of APHP was resulted by its two main pyrolyzed contents phosphorus and alkyl-phosphinic fragments. In condensed phase, the phosphorus-containing contents facilitated to the higher char yields and the formation of intumescent char layer, which led to a reduction of the released fuel and a strong barrier effect to weaken the combustion intensity. In gas phase, the PO, PO2 and alkyl-phosphinic fragments with quenching effect were released from the phosphorus-containing contents, and can decrease the heat release and weaken the combustion intensity.
Urinalysis is an effective strategy to non-invasively evaluate human health, and surface-enhanced Raman scattering (SERS) may be a powerful technique for use in detecting analytes in urine. Herein, ...we report a wearable diaper sensor based on a handheld Raman spectrometer for use in the simple, label-free identification of biomolecules (urea, creatinine, and bilirubin) in urine. The raspberry-shaped Au substrate formed on the surface of an Si wafer provides plasmonic enhancement of the SERS signals, with an excellent uniformity and stability. The SERS sensor combines the advantages of flexibility, portability, and multifunctional detection and may be used in identifying multiple analytes in urine. The sensor exhibits high sensitivities in detecting urea, creatinine, and bilirubin, with respective detection limits of 4.17 × 10−3 M, 5.90 × 10−6 M, and 1.38 × 10−7 M (signal-to-noise ratio = 3). Furthermore, we used the wearable diaper sensor to monitor biomolecules at the diagnostic threshold, facilitating non-invasive diagnosis and medical monitoring of disease-related biomarkers.
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•Noninvasive plasmonic sensor for multiplex biomarkers determination in urine developed.•The raspberry-shaped Au substrate increases uniformity and stability.•The sensor exhibits high sensitivity in the detection of urea, creatinine, and bilirubin.•A hand-held Raman spectrometer for simple SERS urinalysis.
•Spray falling film of oily wastewater over a horizontal tube was investigated.•VOF model was used to track the gas-liquid interface of falling film flow.•The effect of different glycerin content on ...heat transfer was investigated.•The effects of spray parameters and tube parameters were studied.•The temperature distribution inside the liquid film was analyzed.
Sewage heat exchanger is the key equipment of oily sewage source heat pump system, which has great influence on its performance. Among many kinds of heat exchangers, the spray heat exchanger has the advantages of simple structure, high heat transfer efficiency, good operability and anti-blocking ability. Therefore, it can be used in a sewage source heat pump to recover energy from the oily wastewater. However, the heat transfer and flow characteristics of oily wastewater spraying in the heat exchanger are different from the ordinary sewage heat pump system. Hence, it’s necessary to investigate the heat transfer of oily wastewater spray falling film on horizontal tube for better application. In this paper, a three-dimensional numerical model was established for a spraying heat exchanger in the oily sewage source heat pump system, and a mixture of water and glycerin was used to simulate the oily wastewater. The VOF model was used to track the liquid-gas interface of oily wastewater spray falling film over a horizontal tube in the heat exchanger, and the effects of different glycerin content, heat flux, spray density, tube diameter, liquid distributor height and spray temperature on the heat transfer coefficient were investigated. To further understand the mechanism of heat transfer inside the film, the temperature distribution inside the liquid film was obtained and analyzed. The results show that: (1) the heat transfer characteristic can be divided into three regions around the tube; (2) the local heat transfer coefficient decreased with increase of glycerin content in the thermal developing region; (3) the local heat transfer coefficient increased with the increase of the spray density and spray temperature, decreased with the increase of the tube diameter and was little affected by heat flux in the thermal developing region, and the increase in the liquid distributor height caused increase of local heat transfer coefficient in the upper part of the tube.
Evodol is one of the furanoids isolated from the fruits of Evodia rutaecarpa that has been widely prescribed for the treatment of gastrointestinal diseases in China. The aim of this study was to ...investigate the inhibitory effect of evodol on CYP3A.
A 30-min preincubation of evodol with human liver microsomes raised an obvious left IC
50
shift, 3.9-fold for midazolam 1'-hydroxylation and 3.2-fold for testosterone 6β-hydroxylation. Evodol inactivated CYP3A in a time-, concentration- and NADPH-dependent manner, with K
I
and k
inact
of 5.1 μM and 0.028 min
−1
for midazolam 1'-hydroxylation and 3.0 μM and 0.022 min
−1
for testosterone 6β-hydroxylation.
Co-incubation of ketoconazole attenuated the inactivation while the inclusion of glutathione (GSH) and catalase/superoxide dismutase displayed no such protection.
cis-Butene-1, 4-dial (BDA) intermediate derived from evodol were trapped by glutathione and N-acetyl-lysine in microsomes and characterised by HR-MS spectra. The BDA intermediate was believed to play a key role in CYP3A inactivation. CYP3A4 and 2C9 were the primary enzymes contributing to the bioactivation of evodol.
To sum up, for the first time evodol was characterised as a mechanism-based inactivator of CYP3A.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Metastasis to distant organs is a particularly ominous feature of malignant cancer. LKB1 (also known as STK11) has been identified as a tumor suppressor in several types of cancers. Here, we show ...that LKB1 is at low levels and is negatively associated with poor clinical outcomes in pancreatic cancer (PC). LKB1 is inversely correlated with Snail protein in PC, in which the loss of LKB1 facilitates metastasis through elevating Snail protein level. Furthermore, LKB1 boosts Snail's interaction with E3 ligase FBXL14, leading to increasing ubiquitin‐mediated Snail degradation. Notably, metformin could increase Snail protein ubiquitination via augmenting the location of LKB1 at cytoplasm as well as increasing LKB1 expression. Altogether, our data established that LKB1 impedes invasion and metastasis by decreasing the Snail protein level in PC. Targeting the LKB1/FBXL14/Snail axis may represent a promising therapeutic strategy and metformin might be beneficial for PC therapy through activating the LKB1‐mediated Snail ubiquitination pathway.
LKB1 is negatively correlated with Snail at protein level in pancreatic cancer (PC). Loss of LKB1 promotes PC's metastasis via elevating Snail protein in AMPK‐independent pathway. LKB1 enhances E3 ligase FBXL14 to interact with Snail protein, leading to increasing ubiquitin‐mediated Snail degradation Metformin inhibits metastasis through LKB1‐mediated Snail ubiquitination in PC cells.
Seven species from the genus Dictamnus are distributed throughout Europe and North Asia and only two species grow in China. One is Dictamnus dasycarpus Turcz., which could be found in many areas of ...China and has been recorded in Chinese Pharmacopoeia. The other is Dictamnus angustifolius G. Don ex Sweet, which is only present in Xinjiang province and has been used as an alternative for Dictamnus dasycarpus in the local for the treatment of rheumatism, bleeding, itching, jaundice, chronic hepatitis and skin diseases. The present paper reviewed the traditional uses, phytochemistry, pharmacology and toxicology of the genus Dictamnus.
Information on the Dictamnus species was collected from classic books about Chinese herbal medicine and globally accepted scientific databases including PubMed, Elsevier, ASC, Scopus, Google Scholar, Web of Science, CNKI and others.
About 170 chemical compounds, which include quinoline alkaloids, limonoids, sesquiterpenes, coumarins, flavonoids and steroids, have been isolated from the genus Dictamnus. The characteristic and active constituents of Dictamnus species are considered to be quinoline alkaloids and limonoids, which exhibited a broad spectrum of biological activities such as anti-cancer, anti-inflammation, anti-microbe, anti-platelet-aggregation, vascular-relaxation, anti-insect, anti-HIV, anti-allergy and neuroprotection. Moreover, quinoline alkaloids and limonoids could be used as quality control markers to distinguish different species from the genus Dictamnus. However, there were also some reports on the toxic hepatitis and phototoxic effect of Dictamnus species, and the related research needs to be further studied.
In this review, we summarized the chemical constituents, pharmacology, quality control and toxicology of the species from genus Dictamnus. Phytochemical investigations indicated that quinoline alkaloids and limonoids were the major bioactive components with potential cytotoxic, neuroprotective, anti-inflammatory, antimicrobial, anti-platelet-aggregation and vascular relaxing activities. These two kinds of compounds have attracted great interests in the past few years and may have great potential to be new drug lead compounds.
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Long non-coding RNAs (lncRNAs) play key roles in tumorigenesis. It has been reported that the lncRNA nuclear-enriched abundant transcript 1 (NEAT1) may act as an oncogenic regulator in several ...cancers. However, the biological mechanism of action of NEAT1, particularly the miRNA sponge role in colorectal cancer (CRC), has not been fully elucidated. In our study, the expression of NEAT1, miR-205-5p, and vascular endothelial growth factor A (VEGFA) in CRC cell lines were assessed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. Cell proliferation was detected by Cell Counting Kit-8 (CCK-8) assay. Cell migration and invasion were examined by wound healing and transwell assays, respectively. RNA-binding protein immunoprecipitation (RIP), and dual-luciferase and RNA pull-down assays were conducted to determine the correlation between miR-205-5p and NEAT1 or VEGFA. VEGFA, matrix metalloproteinase (MMP)2, and MMP9 protein and mRNA expression were measured by western blotting and RT-qPCR analysis, respectively. Our results demonstrated high expression of NEAT1 and VEGFA and low expression of miR-205-5p in CRC cell lines. The RIP and dual-luciferase assays confirmed miR-205-5p as a target of NEAT1. In addition, VEGFA was identified as a direct target of miR-205-5p. Inhibition of NEAT1 or overexpression of miR-205-5p was able to repress VEGFA expression. Moreover, downregulation of NEAT1 and VEGFA inhibited cell proliferation, migration, and invasion. NEAT1 overexpression facilitated tumor growth by modulating miR-205-5p. Taken together, lncRNA NEAT1 was found to be upregulated in CRC cell lines, promoting CRC cell proliferation, migration, and invasion through regulating the miR-205-5p/VEGFA signaling pathway. These findings suggest that NEAT1 may be a promising biomarker in CRC diagnosis and treatment.
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