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1.
Nanotechnology ; 31(15): 155602, 2020 Apr 10.
Article in English | MEDLINE | ID: mdl-31860881

ABSTRACT

Functional modification and structural design of carbon electrode materials are considered as a cost-effective method to improve their electrochemical performance. In this study, a solvothermal method is applied to realize self-assembly of the metal-organic framework. After simple carbonization and acid treatment, carbon nanosheets with 2D adjustable defective sub-units are successfully prepared for the first time. It is found that carbonization temperature has a significant effect on the carbon skeleton structure. The optimal nanostructures with large specific surface area and appropriate pore size distribution make self-assembled carbon nanosheets having excellent Li/Na-ion storage properties. In addition, the adjustable carbon skeleton structure can effectively avoid irreversible damage when charge-discharge cycles. For Li-ion batteries, a specific capacity of 825 mAh g-1 is achieved after 100 cycles at 100 mA g-1, while for Na-ion batteries a specific capacity of 193 mAh g-1 is observed after 100 cycles at 100 mA g-1. Moreover, for Na-ion batteries, even at a high rate of 1000 mA g-1 the material delivers a specific capacity of 109.5 mAh g-1 after 3500 cycles.

2.
Neuropharmacology ; 133: 38-50, 2018 05 01.
Article in English | MEDLINE | ID: mdl-29325900

ABSTRACT

Orexin-A, -B play a crucial role in arousal and feeding by activating two G-protein-coupled receptors: orexin receptor 1 (OX1R) and orexin receptor 2 (OX2R). Orexins, along with orexin receptors, are expressed in retinal neurons, and they have been shown to differentially modulate excitatory AMPA receptors of amacrine and ganglion cells in the inner retina. In this work we report that orexin-B modulates the activity of rod bipolar cells (RBCs) located in the outer retina of rat. Intravitreal injection of orexin-B increased the amplitude of the scotopic electroretinographic b-wave, a reflection of RBC activity, recorded in vivo. Patch clamp recordings in rat retinal slices showed that orexin-B did not change glutamatergic excitatory component of the RBC response driven by photoreceptors. Effects of orexin-B on GABA receptor-mediated synaptic transmission of RBCs were then examined. In retinal slice preparations orexin-B suppressed GABA receptor-mediated inhibitory postsynaptic currents of RBCs in the inner plexiform layer. Furthermore, using whole-cell recordings in isolated RBCs it was shown that orexin-B suppressed GABAC receptor-, but not GABAA receptor-, mediated currents of the RBCs, an effect that was blocked by OX1R and OX2R antagonists. The orexin-B-induced inhibition of GABAC currents was likely mediated by a Gi/o/PC-PLC/Ca2+-independent PKC signaling pathway, as such inhibition was absent when each step of the above-pathway was blocked with GDP-ß-S/pertussis toxin (for Gi/o), D609 (for PLC), bisindolylmaleimide IV (for PKC)/rottlerin (for PKCδ), respectively. The orexin-B-induced potentiation of RBC activity may improve visual acuity and contrast sensitivity of the animal during the dark period (wake phase).


Subject(s)
Inhibitory Postsynaptic Potentials/drug effects , Orexins/pharmacology , Retina/cytology , Retinal Rod Photoreceptor Cells/drug effects , Synaptic Transmission/drug effects , Animals , Animals, Newborn , Calcium/metabolism , Excitatory Amino Acid Agents/pharmacology , GABA Agents/pharmacology , Glycine/pharmacology , Light , Male , Membrane Potentials/drug effects , Orexin Receptors/metabolism , Patch-Clamp Techniques , Propionates/pharmacology , Rats , Rats, Sprague-Dawley , gamma-Aminobutyric Acid/pharmacology
3.
RSC Adv ; 8(9): 4786-4793, 2018 Jan 24.
Article in English | MEDLINE | ID: mdl-35539531

ABSTRACT

Lithium-sulfur batteries are regarded as a promising energy storage system. However, they are plagued by rapid capacity decay, low coulombic efficiency, a severe shuttle effect and low sulfur loading in cathodes. To address these problems, effective carriers are highly demanded to encapsulate sulfur in order to extend the cycle life. Herein, we introduced a doped-PEDOT:PSS-coated MIL-101/S multi-core-shell structured composite. The unique structure of MIL-101, large specific area and conductive shell ensure high dispersion of sulfur in the composite and minimize the loss of polysulfides to the electrolyte. The doped-PEDOT:PSS-coated sulfur electrodes exhibited an increase in initial capacity and an improvement in rate characteristics. After 192 cycles at the current density of 0.1C, a doped-PEDOT:PSS-coated MIL-101/S electrode maintained a capacity of 606.62 mA h g-1, while the MIL-101/S@PEDOT:PSS electrode delivered a capacity of 456.69 mA h g-1. The EIS measurement revealed that the surface modification with the conducting polymer provided a lower resistance to the sulfur electrode, which resulted in better electrochemical behaviors in Li-S battery applications. Test results indicate that the MIL-101/S@doped-PEDOT:PSS is a promising host material for the sulfur cathode in the lithium-sulfur battery applications.

4.
Neuroscience ; 363: 107-119, 2017 Nov 05.
Article in English | MEDLINE | ID: mdl-28918256

ABSTRACT

Ectopic transgene expression in the retina has been reported in various transgenic mice, indicating the importance of characterizing retinal phenotypes. We examined transgene expression in the VGAT-ChR2-EYFP mouse retina by fluorescent immunohistochemistry and electrophysiology, with special emphasis on enhanced yellow fluorescent protein (EYFP) localization in retinal neuronal subtypes identified by specific markers. Strong EYFP signals were detected in both the inner and outer plexiform layers. In addition, the ChR2-EYFP fusion protein was also expressed in somata of the great majority of inhibitory interneurons, including horizontal cells and GABAergic and glycinergic amacrine cells. However, a small population of amacrine cells residing in the ganglion cell layer were not labeled by EYFP, and a part of them were cholinergic ones. In contrast, no EYFP signal was detected in the somata of retinal excitatory neurons: photoreceptors, bipolar and ganglion cells, as well as Müller glial cells. When glutamatergic transmission was blocked, bright blue light stimulation elicited inward photocurrents from amacrine cells, as well as post-synaptic inhibitory currents from ganglion cells, suggesting a functional ChR2 expression. The VGAT-ChR2-EYFP mouse therefore could be a useful animal model for dissecting retinal microcircuits when targeted labeling and/or optogenetic manipulation of retinal inhibitory neurons are required.


Subject(s)
Interneurons/metabolism , Optogenetics/methods , Recombinant Fusion Proteins/biosynthesis , Retina/metabolism , Animals , Bacterial Proteins/metabolism , Luminescent Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Models, Animal , Rhodopsin/metabolism , Vesicular Inhibitory Amino Acid Transport Proteins/metabolism
5.
Invest Ophthalmol Vis Sci ; 57(13): 5393-5404, 2016 Oct 01.
Article in English | MEDLINE | ID: mdl-27737460

ABSTRACT

PURPOSE: Although retinal dopamine (DA) has been long implicated in myopia development, current studies demonstrate that retinal DA levels are unaltered in C57BL/6 mice with form-deprivation myopia. This work was undertaken to explore whether and how refractive development is perturbed in this mouse strain when retinal DA levels are reduced by 6-hydroxydopamine (6-OHDA) administration. METHODS: On two successive days, 6-OHDA was injected into the vitreous of P18 mice. Retinal DA levels were measured by HPLC and TH levels analyzed by quantitative Western blotting. To choose appropriate 6-OHDA doses that significantly reduce retinal DA levels, but cause minimal disturbance of overall retinal physiology, ERG analysis was performed. Refractive errors were measured using a photorefractor, and ocular biometry performed with optical coherence tomography and photokeratometry. RESULTS: Administration of 6-OHDA of 6.25 µg and 12.5 µg significantly reduced retinal levels of DA and TH, but without affecting ERG a- and b-wave amplitudes. With normal visual experience, 6-OHDA induced myopic refractive shifts in a dose-dependent fashion. Form deprivation induced further myopic shifts in 6-OHDA-injected eyes, but did not cause further decline in retinal DA. Furthermore, 6-OHDA administration resulted in a shorter axial length and a steeper cornea, whereas form deprivation led to a longer axial length, without changing the corneal radius of curvature. CONCLUSIONS: Reducing retinal DA levels led to myopic refractive shifts in C57BL/6 mice, which mainly resulted from a steeper cornea. In addition to the DA-independent mechanism for form-deprivation myopia, there is a DA-dependent mechanism in parallel that underlies myopic refractive shifts under normal laboratory conditions in this mouse strain.


Subject(s)
Dopamine/metabolism , Myopia/metabolism , Oxidopamine/administration & dosage , Refraction, Ocular , Retina/metabolism , Tomography, Optical Coherence/methods , Adrenergic Agents/administration & dosage , Animals , Blotting, Western , Chromatography, High Pressure Liquid , Disease Models, Animal , Dose-Response Relationship, Drug , Electroretinography , Follow-Up Studies , Intravitreal Injections , Male , Mice , Mice, Inbred C57BL , Myopia/diagnosis , Retina/pathology , Retina/physiopathology
6.
Ying Yong Sheng Tai Xue Bao ; 21(8): 1998-2003, 2010 Aug.
Article in Chinese | MEDLINE | ID: mdl-21043107

ABSTRACT

A hydroponic culture experiment was conducted to study the responses of 40 Chamaecrista varieties (lines) to 120 mg x L(-1) of Al3+, with the correlations between the relative tolerance values of various characters of different genotypes and the comprehensive evaluation coefficient compared. Among the characters of the genotypes, the relative plant height, relative root dry mass, relative shoot dry mass, and relative root activity could be selected as the important indices for screening the Al-tolerant genotype of Chamaecrista. In the test 40 Chamaecrista varieties (lines), the 86134R2, 2208, 3170, 316, 2211, and 2232 had stronger Al-tolerant capability, belonging to Al-tolerant genotype, whereas the 34721R1, 92985, and 3184 had weaker Al-tolerant capacity, belonging to Al-sensitive genotype.


Subject(s)
Adaptation, Physiological , Aluminum/toxicity , Chamaecrista/genetics , Chamaecrista/drug effects , Genotype
7.
Brain Res Bull ; 82(3-4): 188-92, 2010 May 31.
Article in English | MEDLINE | ID: mdl-20304036

ABSTRACT

Natriuretic peptides (NPs) exert their actions through three membrane-bound receptors, which are known as NP receptors (NPRs: NPR-A, NPR-B and NPR-C). In this work we examined the expression of three NPRs in rat retinal ganglion cells (GCs), retrogradely labeled and intracellularly dye-injected, by double immunofluorescence labeling. In vertical sections, almost all GCs, retrogradely labeled by cholera toxin B, were stained by antibodies against the three NPRs. The labeling for three NPRs was observed mainly on the membranes of the somata of GCs, whereas the staining for NPR-A was also seen in the cytoplasm. Moreover, with tangential sections, almost all cells located in the ganglion cell layer were NPR-A, B, C immunoreactive. By combining with intracellular injection of Neurobiotin into GCs in whole mount retinas that enables to identify ON-, OFF- and ON-OFF-types of GCs according to arborization of their dendrites in the inner plexiform layer, we further demonstrated that NPRs were expressed in these major types of GCs.


Subject(s)
Natriuretic Peptides/metabolism , Protein Isoforms/metabolism , Receptors, Atrial Natriuretic Factor/metabolism , Retinal Ganglion Cells/metabolism , Animals , Rats , Rats, Sprague-Dawley , Retinal Ganglion Cells/cytology
8.
Environ Pollut ; 156(3): 1149-55, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18457908

ABSTRACT

This study investigates As accumulation and tolerance of the aquatic fern Azolla. Fifty strains of Azolla showed a large variation in As accumulation. The highest- and lowest-accumulating ferns among the 50 strains were chosen for further investigations. Azolla caroliniana accumulated two times more As than Azolla filiculoides owing to a higher influx velocity for arsenate. A. filiculoides was more resistant to external arsenate due to a lower uptake. Both strains showed a similar degree of tolerance to internal As. Arsenate and arsenite were the dominant As species in both Azolla strains, with methylated As species accounting for <5% of the total As. A. filiculoides had a higher proportion of arsenite than A. caroliniana. Both strains effluxed more arsenate than arsenite, and the amount of As efflux was proportional to the amount of As accumulation. The potential of growing Azolla in paddy fields to reduce As transfer from soil and water to rice should be further evaluated.


Subject(s)
Arsenic/pharmacokinetics , Ferns/metabolism , Water Pollutants, Chemical/metabolism , Arsenates/metabolism , Arsenic/analysis , Biodegradation, Environmental , Biological Availability , Biological Transport , Ecology/methods , Ferns/chemistry , Phosphorus/analysis , Phosphorus/metabolism , Plant Shoots/chemistry , Plant Shoots/metabolism , Species Specificity
9.
Zhonghua Wai Ke Za Zhi ; 41(11): 856-60, 2003 Nov.
Article in Chinese | MEDLINE | ID: mdl-14703465

ABSTRACT

OBJECTIVE: To observe the effects and mechanisms of endotoxin pretreatment on the rat lung in endotoxemia. METHODS: Eighty-four male Wistar rats were divided into seven groups (each group containing 12 rats): saline control and lipopolysaccharide (LPS)-treated 2 h, 4 h, 6 h groups and LPS-pretreated 2 h, 4 h, 6 h groups. LPS-pretreated rats were administrated with intraperitoneal injection of 0.25 mg/kg LPS. After 24 hours, they were injected with 0.5 mg/kg of LPS. Saline control and LPS-treated rats received an equivalent amount of saline. After 72 hours, LPS-treated and LPS-pretreated rats were intravenously injected with 10 mg/kg of LPS. An equivalent amount of saline was injected in the control rats. Blood was drawn from the carotid artery in LPS-treated and LPS-pretreated rats and sacrificed after intravenous injection of LPS 2, 4, 6 hours. Following saline injection of control rats, blood was drawn from the carotid artery after 6 hours. Arterial blood was drawn for blood gas analysis. The lungs were removed for detecting the mRNA levels of intercellular adhesion molecule-1 (ICAM-1) by reverse transcription polymerase chain reaction and the protein levels of inhibitor kappa B-alpha (I kappa B-alpha) by immunohistochemical staining. Bronchoalveolar lavage was performed in the right lung. Cell counts were evaluated with a light microscopy. The supernatant of bronchoalveolar lavage fluid (BALF) was assayed for the level of protein. The whole lung was weighed and the value was used to determine the lung-body index. The tissue was homogenized and centrifuged for the determination of myeloperoxidase enzyme (MPO) activity. RESULTS: The rats exposed to LPS alone demonstrated an increase in lung-body index, protein in BALF, and MPO activity in the lung tissue. In contrast, the rats exposed to LPS pretreatment exhibited a significant decrease in lung-body index, protein in BALF, and MPO activity. There was a significant decrease in the level of arterial bicarbonate in the LPS-treated rats in comparison with saline-treated and LPS-pretreated animals at 2 hours to 6 hours after LPS administration. The decrease of arterial bicarbonate was compensated by alveolar hyperventilation in LPS-treated animals, with a significant decrease in partial pressure of carbon dioxide. At the same time, partial pressure of oxygen decreased significantly compared with saline control animals and LPS-pretreated animals. LPS-treated rats showed a significant gradually increase in ICAM-1mRNA in the lung in comparison with the saline group. In contrast, ICAM-1mRNA levels in rats pretreated with LPS was lower than that in LPS-treated rats. In LPS-treated animals, LPS caused a decrease of I kappa B-alpha protein expression at 2 hours, returned to control level at 4 hours, and remained at 6 hours. There was no decrease of I kappa B-alpha protein expression in LPS-pretreated animals. CONCLUSION: The results in this study showed that administration of a small dose of LPS 72 hours before endotoxemia caused a attenuation effect on lung injury, which may be correlated to I kappa B-alpha expression induced by LPS pretreatment.


Subject(s)
Endotoxemia/metabolism , Lipopolysaccharides/pharmacology , Lung/metabolism , Animals , Carbon Dioxide/blood , I-kappa B Proteins/analysis , I-kappa B Proteins/metabolism , Immunohistochemistry , Intercellular Adhesion Molecule-1/genetics , Lung/pathology , Male , NF-KappaB Inhibitor alpha , Oxygen/blood , Peroxidase/metabolism , RNA, Messenger/analysis , Rats , Rats, Wistar
10.
Yi Chuan ; 24(1): 45-9, 2002 Jan.
Article in Chinese | MEDLINE | ID: mdl-15901562

ABSTRACT

Symbiotic Anabeana azollae and its host plant Anabeana-free Azolla were isolated from 16 Azolla accessions representing different Azolla species or geographic origins.DNA polymorphic fragments were obtained by simultaneous RAPD amplification of both symbiont and host. The UPGMA clusters of Anabeana azollae and its host Azolla were established separately based on Dice coefficient caculation and a coordinated relationship was shown between Anabeana azollae and its Azolla host along both individual genetic divergence,but this genetic homology was reduced among different strains within Azolla species while the obvious mutants of Anabeana azollae were detected in some Azolla tested strains collected from different geographic area in the same host species.

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