The goal of this study was to develop transgenic plants with increased tolerance for and accumulation of heavy metals and metalloids from soil by simultaneous overexpression of
AsPCS1 and
GSH1 ...(derived from garlic and baker’s yeast) in
Arabidopsis thaliana. Phytochelatins (PCs) and glutathione (GSH) are the main binding peptides involved in chelating heavy metal ions in plants and other living organisms. Single-gene transgenic lines had higher tolerance to and accumulated more Cd and As than wild-type. Compared to single-gene transgenic lines, dual-gene transformants exhibited significantly higher tolerance to and accumulated more Cd and As. One of the dual-gene transgenic lines, PG1, accumulated twice the amount of Cd as single-gene transgenic lines. Simultaneous overexpression of
AsPCS1 and
GSH1 led to elevated total PC production in transgenic
Arabidopsis. These results indicate that such a stacking of modified genes is capable of increasing Cd and As tolerance and accumulation in transgenic lines, and represents a highly promising new tool for use in phytoremediation efforts.
As an environmentally friendly and resource-rich energy, hydrogen is recognized as an ideal alternative to conventional fossil fuels. Among various methods for hydrogen production, electrochemical ...water splitting is one of the most promising approaches, for which hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are crucial for determining the performance. Recently, much research has shown heterostructure catalysts to possess competitive electrocatalytic performance toward HER and OER. However, compared with their theoretical activities, many heterostructure catalysts remain somewhat unsatisfactory and have a long way to go. With the aim of ultimately enhancing electrocatalytic performance, recent approaches for the modification of heterostructure catalysts are summarized in this review. Typical synthetic strategies, such as design of nanostructure, chemical doping, and heterostructure-based hybrids synthesis, are discussed, and their advantages are highlighted. Finally, perspectives on the future direction of heterostructure electrocatalysts toward water splitting are presented.
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Achieving optimum catalytic performance via the rational regulation of heterostructure catalysts has attracted extensive attention from the catalysis community recently. In this review, we comprehensively summarize recent approaches in the modification of heterostructure catalysts and their mechanism toward improved water splitting.
An ionic liquid-based microwave-assisted extraction (ILMAE) approach has been successfully applied to the effective extraction of the phenolic alkaloids present in samples of the medicinal plant
...Nelumbo nucifera Gaertn. The ionic liquids investigated comprised a range of four anions, four 1-alkyl-3-methylimidazolium derivatives differing in hydrophobic chain length. The results indicate that varying the anion has apparent effects on the overall extraction efficiency. In addition, the influence of some microwave parameters, such as irradiation power, extraction time and solid–liquid ratio, are also investigated. Under the optimized conditions, the proposed approach has been evaluated in comparison with the conventional heat-reflux extraction (HRE) and regular MAE. The reduction of the extraction times (from 2
h to 90
s) and remarkable higher efficiency (20–50% improved) supports the suitability of the proposed approach. In addition, the proposed method is validated by the recovery, correlation coefficient (
R
2), and reproducibility (RSD,
n
=
5), which are in the range of 98–105%, 0.9994–0.9998, and 1.2–5.4%, respectively.
Urea electrolysis is regarded as a prospective method for energy-saving hydrogen production. However, the practical application of this technology is limited by the lack of high-performance ...bifunctional catalysts for hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). Herein, a heterostructure catalyst composed of NiFe layered double hydroxide (LDH) and sulfides (NiFe LDH-NiFeSx/NF) catalysts is prepared via a simple one-step hydrothermal approach. Remarkably, the prepared NiFe LDH-NiFeSx/NF required 138 mV and 1.34 V to achieve 10 mA cm−2 for HER and UOR in 1 M KOH and 0.33 M urea, respectively. Furthermore, when NiFe LDH-NiFeSx/NF is used as a cathode for urea electrolysis, only 1.44 V is required at 10 mA cm−2, which is much lower than the 1.53 V needed for overall water splitting.
Dlx1, a member of the homeobox domain transcriptional factors, is expressed in a subset of interneurons and is involved in their differentiation. To understand the roles of Dlx1 in dendritic and ...postsynaptic differentiation, we manipulated Dlx1 expression in both excitatory pyramidal neurons and inhibitory interneurons in hippocampal culture. Exogenous expression of Dlx1 in pyramidal neurons, which lack endogenous Dlx1, resulted in reduced complexity of dendritic arborization. This effect was dependent on the DNA‐binding motif of Dlx1. Dlx1 overexpression also induced prominent reduction of spine density, but with mild suppression in the formation of postsynaptic densities. To confirm the roles of endogenous Dlx1, we knocked down Dlx1 in interneurons and found enhanced dendritic growth. By manipulating the expression of possible downstream effectors of Dlx1, neuropilin‐2 and p21‐activated kinase 3, we provided evidence for the involvement of these two signaling molecules in Dlx1‐dependent regulation of dendritic differentiation. Our experimental data support the idea that Dlx1 expression in developing interneurons specifically suppresses two important downstream regulators, leading to the characteristic morphology of Dlx1‐expressing interneurons with less branched dendrites and few dendritic spines.
Dlx1 is expressed in mouse hippocampal interneurons. Overexpression of Dlx1 in excitatory pyramidal neurons reduces the number of dendrites dramatically and the resultant morphology of neuron becomes similar to that of interneurons. Conversely, downregulation of Dlx1 increases the number of dendrites in interneurons. These results suggest the role of Dlx1 as an endogenous regulator of dendrite morphogenesis in interneurons.
In this paper, five isoquinoline alkaloids were successfully separated from a crude extract of
Stephania yunnanensis using pH-zone-refining counter-current chromatography in single-step. With a ...two-phase solvent system composed of methyl-
tert-butyl ether (MtBE)–acetonitrile–water (2:2:3, v/v) where triethylamine (10
mM) was added to the upper organic phase as a retainer and hydrochloric acid (5
mM) to the aqueous mobile phase as an eluter. From 1.4
g crude extract, 68.7
mg isocorydine, 78.2
mg corydine, 583.4
mg tetrahydropalmatine, 36.3
mg N-methylasimilobine, and 47.3
mg anonaine were separated with purities over 90%. Their structures were identified by
1H NMR,
13C NMR, ESI-MS data.
Background Fenofibrate is a fibric acid derivative known to have a lipid-lowering effect. Although fenofibrate-induced peroxisome proliferator-activated receptor alpha (PPARalpha) transcription ...activation has been shown to play an important role in the malignant progression of gliomas, the underlying mechanisms are poorly understood. Methods In this study, we analyzed TCGA database and found that there was a significant negative correlation between the long noncoding RNA (lncRNA) HOTAIR and PPARalpha. Then, we explored the molecular mechanism by which lncRNA HOTAIR regulates PPARalpha in cell lines in vitro and in a nude mouse glioma model in vivo and explored the effect of the combined application of HOTAIR knockdown and fenofibrate treatment on glioma invasion. Results For the first time, it was shown that after knockdown of the expression of HOTAIR in gliomas, the expression of PPARalpha was significantly upregulated, and the invasion and proliferation ability of gliomas were obviously inhibited. Then, glioma cells were treated with both the PPARalpha agonist fenofibrate and si-HOTAIR, and the results showed that the proliferation and invasion of glioma cells were significantly inhibited. Conclusions Our results suggest that HOTAIR can negatively regulate the expression of PPARalpha and that the combination of fenofibrate and si-HOTAIR treatment can significantly inhibit the progression of gliomas. This introduces new ideas for the treatment of gliomas. Keywords: Glioblastoma, Fenofibrate, HOTAIR, PPARA, Therapy
Mammalian skeletal muscles contain a number of heterogeneous cell populations. Our previous study characterized a unique population of myogenic lineage stem cells that can be isolated from adult ...mammalian skeletal muscles upon injury. These injury-induced muscle-derived stem cell-like cells (iMuSCs) displayed a multipotent state with sensitiveness and strong migration abilities. Here, we report that these iMuSCs have the capability to form neurospheres that represent multiple neural phenotypes. The induced neuronal cells expressed various neuron-specific proteins, their mRNA expression during neuronal differentiation recapitulated embryonic neurogenesis, they generated action potentials, and they formed functional synapses in vitro. Furthermore, the transplantation of iMuSCs or their cell extracts into the muscles of mdx mice (i.e., a mouse model of Duchenne Muscular Dystrophy DMD) could restore the morphology of their previously damaged neuromuscular junctions (NMJs), suggesting that the beneficial effects of iMuSCs may not be restricted to cell restoration alone, but also due to their transient paracrine actions. The current study reveals the essential role of iMuSCs in the restoration of NMJs related to injuries and diseases.
We have previously shown that remote ischemic preconditioning by limb ischemia (rIPC) or intra-arterial adenosine releases a dialyzable cardioprotective circulating factor(s), the release of which ...requires an intact neural connection to the limb and is blocked by pretreatment with
S
-nitroso-
N
-acetylpenicillamine (SNAP). Remote cardioprotection can be induced by other forms of peripheral stimulation including topical capsaicin, but the mechanisms of their signal transduction are incompletely understood. Rabbits were anesthetized by intravenous pentobarbital, intubated and ventilated, then randomized (4–7 animals in each group) to receive sham procedure, rIPC (4 cycles of 5 min lower limb ischemia, 5 min reperfusion), direct femoral nerve stimulation, topical capsaicin, pretreatment with intra-arterial SNAP + capsaicin, pretreatment with topical DMSO (a sensory nerve blocker) + topical capsaicin, or pretreatment with intra-arterial SNAP + femoral nerve stimulation, topical DMSO alone, or intra-arterial SNAP alone. Blood was then rapidly drawn from the carotid artery to produce the plasma dialysate which was used to perfuse a naïve heart from an untreated donor rabbit. The infarct size and recovery of LV-developed pressure and end-diastolic pressure were measured after 30 min of global ischemia and 120 min of reperfusion. Compared to sham, dialysate from rIPC, femoral nerve stimulation, and topical capsaicin groups all produced significant cardioprotection with significantly reduced infarct size, and improved the post-ischemic cardiac performance. Cardioprotection was not seen in the topical DMSO-capsaicin, SNAP + capsaicin, and SNAP + FNS groups. These results confirm the central role of peripheral nerves in the local signal transduction of remote cardioprotection. Direct electrical or peripheral neural stimulation evokes the release of cardioprotective substances into the bloodstream, with comparable effects to that of rIPC induced by limb ischemia.
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