Controllable Fabrication of Vertical Graphene with Tunable Growth Nature by Remote Plasma-Enhanced Chemical Vapor Deposition.

As an important member of the graphene family, vertical graphene (VG) has broad applications like field emission, energy storage, and sensors owing to its fascinating physical and chemical properties. Among various fabrication methods for VG, plasma enhanced chemical vapor deposition (PECVD) is most employed because of the fast growth rate at relatively low temperature for the high-quality VG. However, to date, relations between growth manner of VG and growth parameters such as growth temperature, dosage of gaseous carbon source, and electric power to generate plasma are still less known, which in turn hinder the massive production of VG for further applications. In this study, the growth behavior of VG was studied as functions of temperature, plasma power, and gas composition (or chamber pressure). It was found that the growth behavior of VG is sensitive to the growth conditions mentioned above. Although conditions with high growth temperature, large flow rate of mixed gas of methane and carrier gases, and high plasma power may be helpful for the fast growth of VG, brunching of VG is simultaneously enhanced, which in turn decreases the vertical growth nature of VG. High-quality VG can be achieved by optimizing the growth parameters. It was revealed that the vertical growth nature of VG is governed by the electric field at the interfacial layer between VG and the substrate, for which its strength is influenced by the density of plasma. These findings are important for the general understanding of the VG growth and provided a feasible way for the controllable fabrication of VG using the remote PECVD method which is usually believed to be unsuitable for the fabrication of VG.

(1)H NMR-based metabolic profiling of liver in chronic unpredictable mild stress rats with genipin treatment.

Genipin, a hydrolyzed metabolite of geniposide extracted from the fruit of Gardenia jasminoides Ellis, has shown promise in alleviating depressive symptoms, however, the antidepressant mechanism of genipin remains unclear and incomprehensive. In this study, the metabolic profiles of aqueous and lipophilic extracts in liver of the chronic unpredictable mild stress (CUMS)-induced rat with genipin treatment were investigated using proton nuclear magnetic resonance ((1)H NMR) spectroscopy coupled with multivariate data analysis. Significant differences in the metabolic profiles of rats in the CUMS model group (MS) and the control group (NS) were observed with metabolic effects including decreasing in choline, glycerol and glycogen, increasing in lactate, alanine and succinate, and a disordered lipid metabolism, while the moderate dose (50mg/kg) of genipin could significantly regulate the concentrations of glycerol, lactate, alanine, succinate and the lipid to their normal levels. These biomakers were involved in metabolism pathways such as glycolysis/gluconeogensis, tricarboxylic acid (TCA) cycle and lipid metabolism, which may be helpful for understanding of antidepressant mechanism of genipin.

[1H NMR based metabonomics study on the antidepressant effect of genipin in rat hippocampus].

The purpose of this study is to explore depression metabolic markers in rat hippocampus and to investigate the anti-depressant effect of genipin and its mechanisms using nuclear magnetic resonance (NMR) metabonomics. Chronic unpredictable mild stress (CUMS) procedure was conducted to establish the depressive rat model. At the beginning of the third week, genipin low dose (25 mg x kg(-1)), middle dose (50 mg x kg(-1)), high dose (100 mg x kg(-1)), and venlafaxine (50 mg x kg(-1)) were given to the CUMS rats separately once daily for two weeks except control and model groups. Rat hippocampus was analyzed by 1H NMR based metabonomics after drug administration for 2 weeks. Significant differences in the metabolic profile of rat hippocampus of the CUMS treated group and the control group were observed with metabolic effects of CUMS including decreasing in glycine and N-acetylaspartate, increasing in inositol, glutamate, lactate, glutamine, taurine and alanine. Genipin showed ideal antidepressive effects at a dose of 50 mg x kg(-1) in rats, decrease of inositol, glutamate, lactate, alanine were observed, while glycine and N-acetylaspartate were increased. Important influence has been found on normal nervous system function of these significant changed metabolites, which suggests that the antidepressant effect of genipin may be played by enhancing the activity of neurons in hippocampus, repairing and improving the function of the neuron. The metabonomics approach is an effective tool for the investigation of the anti-depressant effect and pharmacologic mechanisms of genipin.

1H-NMR-based metabonomic studies on the anti-depressant effect of genipin in the chronic unpredictable mild stress rat model.

The purpose of this work was to investigate the anti-depressant effect of genipin and its mechanisms using (1)H-NMR spectroscopy and multivariate data analysis on a chronic unpredictable mild stress (CUMS) rat model. Rat serum and urine were analyzed by nuclear magnetic resonance (NMR)-based metabonomics after oral administration of either genipin or saline for 2 weeks. Significant differences in the metabolic profile of the CUMS-treated group and the control group were observed, which were consistent with the results of behavioral tests. Metabolic effects of CUMS included decreases in serum trimetlylamine oxide (TMAO) and ß-hydroxybutyric acid (ß-HB), and increases in lipid, lactate, alanine and N-acetyl-glycoproteins. In urine, decreases in creatinine and betaine were observed, while citrate, trimethylamine (TMA) and dimethylamine were increased. These changes suggest that depression may be associated with gut microbes, energy metabolism and glycometabolism. Genipin showed the best anti-depressive effects at a dose of 100 mg/kg in rats. These results indicate that metabonomic approaches could be powerful tools for the investigation of the biochemical changes in pathological conditions or drug treatment.