Monoclinic Li3V2(PO4)3 can be synthesized by solid-state reaction using either hydrogen or carbon as the reducing agent when sintering temperatures are higher than 800 deg C. The initial capacity of ...Li3V2(PO4)3 synthesized using hydrogen as the reducing agent increases with increasing sintering temperature T and then for T > 900 deg C decreases monotonically, and the sample synthesized at 900 deg C present the highest initial capacity of 146.3mAhg-1, but exhibit poor cycle performance. The scanning electron microscope (SEM) images show that Li3V2(PO4)3 particles with small uniform particle size can be obtained at 900 deg C. X-ray diffraction patterns of electrodes before and after cycling indicate that the capacity fading is not related to structure collapse. The carbon-coated Li3V2(PO4)3 (LVP/C) composites are synthesized by carbo-thermal reduction method at the optimized temperature of 900 deg C. The LVP/C exhibit good cycle performance (137.5mAhg-1 at 50th cycle under 1C rate, 94.6% of initial discharge capacity) and rate behavior (111.0mAhg-1 under 5C rate for initial discharge) for the fully de-lithiated (3-4.8V) samples. Our results suggest, based on the SEM images, that the good capacity retention and rate performance are owing to the nanometer size carbon webs coated the Li3V2(PO4)3 particles with both the greater specific surface area and the small uniform particle size.
► Ionic liquid-based microwave-assisted extraction was developed. ► Extraction process was performed at room temperature and atmospheric pressure. ► Fast extraction of active ingredient in
C. ...paniculatum was achieved.
For increasing active ingredients accessibility to the solvents, microwave assisted ionic liquid pretreatment (MILP) is introduced to destroy cell walls of medicinal plants before solvent extraction. As a new sample pretreatment method, microwave irradiation on sample pretreatment with ionic liquids (ILs) was investigated. The conditions of MILP including microwave pretreatment time and power, ionic liquid (IL) and sample ratio and particle size were optimized and
Cynanchum paniculatum and its active ingredient paeonol were chosen as the representative target analyte. Under the optimized conditions, the paeonol extraction yield by MILP was higher than that of ionic liquid aqueous solution and Soxhlet extraction. In addition, the results of bioassay test showed that the antibacterial effect of crude extract by MILP was almost the same with that of soxhlet extraction. Our results demonstrate that sample pretreatment with ILs and microwave irradiation is a potential alternative method for the pretreatment of medicinal plants before solvent extraction.
Monoclinic lithium vanadium phosphate, Li3V2(PO4)3, has been successfully synthesized using LiF as lithium source. The one-step reaction with stoichiometric composition and relative lower sintering ...temperature (700 deg C) has been used in our experimental processes. The solid-state reaction mechanism using LiF as lithium precursor has been studied by X-ray diffraction and Fourier transform infrared spectra. The Rietveld refinement results show that in our product sintered at 700 deg C no impurity phases of VPO4, Li5V(PO4)2F2, or LiVPO4F can be detected. The solid-state reaction using Li2CO3 as Li-precursor has also been carried out for comparison. X-ray diffraction patterns indicate that impurities as Li3PO4 can be found in the product using Li2CO3 as Li-precursor unless the sintering temperatures are higher than 850 deg C. An abrupt particle growth (about 2mum) has also been observed by scanning electron microscope for the samples sintered at higher temperatures, which can result in a poor cycle performance. The product obtained using LiF as Li-precursor with the uniform flake-like particles and smaller particle size (about 300nm) exhibits the better performance. At the 50th cycle, the reversible specific capacities for Li3V2(PO4)3 measured between 3 and 4.8V at 1C rate are found to approach 147.1mAh/g (93.8% of initial capacity). The specific capacity of 123.6mAh/g can even be hold between 3 and 4.8V at 5C rate.
Distraction osteogenesis (DO) is used to treat large bone defects in the field of oral and maxillofacial surgery. Successful DO-mediated bone regeneration is dependent upon angiogenesis, and ...endothelial progenitor cells (EPCs) are key mediators of angiogenic processes. The
N6
-methyladenosine (m
6
A) methyltransferase has been identified as an important regulator of diverse biological processes, but its role in EPC-mediated angiogenesis during DO remains to be clarified. In the present study, we found that the level of m
6
A modification was significantly elevated during the process of DO and that it was also increased in the context of EPC angiogenesis under hypoxic conditions, which was characterized by increased METTL3 levels. After knocking down METTL3 in EPCs, m
6
A RNA methylation, proliferation, tube formation, migration, and chicken embryo chorioallantoic membrane (CAM) angiogenic activity were inhibited, whereas the opposite was observed upon the overexpression of METTL3. Mechanistically, METTL3 silencing reduced the levels of VEGF and PI3Kp110 as well as the phosphorylation of AKT, whereas METTL3 overexpression reduced these levels. SC79-mediated AKT phosphorylation was also able to restore the angiogenic capabilities of METTL3-deficient EPCs
in vitro
and
ex vivo
.
In vivo
, METTL3-overexpressing EPCs were additionally transplanted into the DO callus, significantly enhancing bone regeneration as evidenced by improved radiological and histological manifestations in a canine mandibular DO model after consolidation over a 4-week period. Overall, these results indicate that METTL3 accelerates bone regeneration during DO by enhancing EPC angiogenesis via the PI3K/AKT pathway.
A liquid-based sol-gel method was developed to synthesize nanocarbon-coated Li3V2(PO4)3. The products were characterized by XRD, SEM and electrochemical measurements. The results of Rietveld ...refinement analysis indicate that single-phase Li3V2(PO4)3 with monoclinic structure can be obtained in our experimental process. The discharge capacity of carbon-coated Li3V2(PO4)3 was 152.6mAh/g at the 50th cycle under 1C rate, with 95.4% retention rate of initial capacity. A high discharge capacity of 184.1mAh/g can be obtained under 0.12C rate, and a capacity of 140.0mAh/g can still be held at 3C rate. The cyclic voltammetric measurements indicate that the electrode reaction reversibility is enhanced due to the carbon-coating. SEM images show that the reduced particle size and well-dispersed carbon-coating can be responsible for the good electrochemical performance obtained in our experiments.
Mitochondria dysfunction is one of the primary causes of tubular injury in acute kidney injury (AKI). Notoginsenoside Fc (Fc), a new saponin isolated from Panax notoginseng, exhibited numerous ...pharmacological actions. However, the beneficial effects of Fc on renal tubular impairment and mitochondrial dysfunction in AKI have not been fully studied.
In this study, we established acetaminophen (APAP)-induced AKI model in mice to examine the therapeutic impacts of Fc on AKI.
Our results showed that Fc could decrease the levels of the serum creatinine (Scr), blood urea nitrogen (BUN) and Cystatin C in mice with AKI. Fc also ameliorated renal histopathology, renal tubular cells apoptosis and restored expression of apoptosis-related proteins such as Bax, Bcl-2 and caspase3 (C-caspase3). Additionally, Fc increased the protein expression of SIRT3 and SOD2 in kidneys from mice with AKI.
studies further showed Fc reduced the apoptosis of HK-2 cells exposure to APAP, attenuated the loss of mitochondrial membrane potential and decreased the formation of mitochondrial superoxide. Fc also partly restored the protein expression of Bax, Bcl-2, C-Caspase3, SIRT3, and SOD2 in HK-2 cells exposure to APAP.
In summary, Fc might reduce renal tubular injury and mitochondrial dysfunction in AKI partly through the regulation of SIRT3/SOD2 pathway.
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