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1.
Epilepsy Res ; 156: 106183, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31404716

RESUMO

To investigate the neuroprotective effect of ferulic acid (FA) in a pentylenetetrazol (PTZ)-induced seizures model in rat, the motor response, spatial learning ability and memory capability of the rats were assessed. Both the antioxidation and anti-apoptosis pathways were also investigated. In this study, male Wistar rats were randomly divided into 3 groups (n = 12 in each group). For 28 days, the rats were administered saline alone (i.p. normal saline, NS group), PTZ (40 mg/kg, i.p., PTZ group) once daily to induce seizures, or FA (i.p. 60 mg/kg) 20 min before being given PTZ (40 mg/kg, i.p., FA + PTZ group) to assess the neuroprotective effect of FA. The motor response of the rats was analysed with the Racine scale. The spatial learning and memory capacity of the rats were assessed by the Morris water maze test. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were measured, and both in situ staining with the DNA-binding bisbenzimide Hoechst 33258 and TUNEL assays were used to assess apoptosis. Western blotting was used to further analyse the expression of Apaf-1, caspase-9, caspase-3, Bcl-2, Bid, Bax, cleaved caspase-3 and cytochrome c. The results showed that compared to the those of the PTZ group, FA pre-treatment significantly (p < 0.01) reduced the Racine scores starting at day 4, prolonged the latency of the onset of seizure at day 28, reduced the escape latency period starting at day 2, increased the frequency of crossing the platform location, increased the SOD activity, reduced the MDA content and apoptosis percentage, and upregulated the Bcl-2 levels whilst downregulating the Bax, cytochrome c, Apaf-1, caspase-9, caspase-3, cleaved caspase-3 and Bid expression levels. This study demonstrated that pre-treatment with FA exerts strong neuroprotective effects by reducing the motor response and by improving spatial learning ability and memory capacity. The neuroprotective effect may be a result of a reduction in neuron cell death that occurs via the antioxidative and anti-apoptotic pathways.

2.
Adv Sci (Weinh) ; 6(16): 1900190, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31453057

RESUMO

The interfacial decomposition products forming the so-called solid-electrolyte interphase (SEI) significantly determine the destiny of a Li-ion battery. Ultimate knowledge of its detailed behavior and better control are required for higher rates, longer life-time, and increased safety. Employing an electrochemical surface force apparatus, it is possible to control the growth and to investigate the mechanical properties of an SEI in a lithium-ion battery environment. This new approach is here introduced on a gold model system and reveals a compressible film at all stages of SEI growth. The demonstrated methodology provides a unique tool for analyzing electrochemical battery interfaces, in particular in view of alternative electrolyte formulations and artificial interfaces.

3.
Front Microbiol ; 9: 2069, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30233542

RESUMO

Both high- and low-pathogenic H7N9 influenza A virus (IAV) infections have been found in human and poultry in China, and most human cases are related to contact with infected poultry. It is necessary to develop a rapid and simple method to detect H7N9 IAV in poultry. In this study, 13 monoclonal antibodies (McAbs) against the H7N9 IAV hemagglutinin were developed, and three critical amino acid epitopes (198, 227, 235) were identified based on the reactivity of these variant and wild-type strains with the McAbs. We developed an immunochromatographic assay for H7N9 AIVs using two McAbs recognizing the epitope position 227 and 235. The assay had good specificity, stability, and sensitivity, with a detection limit of swab and tissue samples of 2.5 log10EID50/0.1 mL, which is suitable for the analysis of clinical samples. This assay provides an effective method for the rapid detection of H7N9 AIVs in poultry.

4.
Chemphyschem ; 18(21): 3056-3065, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-28872763

RESUMO

The molecular structure at charged solid/liquid interfaces is vital for many chemical or electrochemical processes, such as adhesion, catalysis, or the stability of colloidal dispersions. How cations influence structural hydration forces and interactions across negatively charged surfaces has been studied in great detail. However, how anions influence structural hydration forces on positively charged surfaces is much less understood. Herein we report force versus distance profiles on freshly cleaved mica using atomic force microscopy with silicon tips. We characterize steric anion hydration forces for a set of common anions (Cl- , ClO4- , NO3- , SO42- and PO43- ) in pure acids at pH ≈1, where protons are the co-ions. Solutions containing anions with low hydration energies exhibit repulsive structural hydration forces, indicating significant ion and/or water structuring within the first 1-2 nm on a positively charged surface. We attribute this to specific adsorption effects within the Stern layer. In contrast, ions with high hydration energies show exponentially repulsive hydration forces, indicating a lower degree of structuring within the Stern layer. The presented data demonstrates that anion hydration forces in the inner double layer are comparable to cation hydration forces, and that they qualitatively correlate with hydration free energies. This work contributes to understanding interaction processes in which positive charge is screened by anions within an electrolyte.

5.
Inorg Chem ; 56(17): 10204-10214, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28805370

RESUMO

An m-phthalic diamide-linked bisporphyrin with a benzylamide substituent has been designed and synthesized. It has two types of carbonyl groups. In the solution of this zinc bisporphyrinate, these carbonyl groups are involved in the formation of two different Zn-O coordination interactions: one is formed between neighboring zinc bisporphyrinates; another is formed within zinc bisporphyrinate. The chirality sensing abilities of this zinc porphyrinate to a number of chiral monoamines have been examined. When zinc bisporphyrinate was mixed with a series of chiral monoamines, the signs of the circular dichroism spectra for the chiral monoamines of the same handedness with an aryl group as the substituent are just opposite to those with an alkyl group as the substituent. NMR studies reveal that stepwise coordinations lead to 1:1 and 1:2 host-guest complexes. The structure of the 1:1 host-guest complex was confirmed by crystallography, it is the first time that a 1:1 host-guest complex formed between zinc bisporphyrinate and a chiral monoamine has been crystallographically characterized. The structure reveals that there is an intramolecular hydrogen bond between the amide oxygen and the coordinated NH2. We further investigated the chirality transfer mechanism by density functional theory calculations. Our studies suggest that the interactions between the linker and guests in this bisporphyrin system are crucial in the chirality transfer process, and the nature of the bulkiest substituent of chiral monoamines makes a difference. For R-type guests, with an alkyl group, the steric repulsion makes the conformer A more energetically favorable, which leads to the anticlockwise twist and negative Cotton effect. However, with an aryl group, the π-π interaction makes the conformer B more energetically favorable, which leads to the clockwise twist and positive Cotton effect.

6.
Nat Commun ; 7: 12693, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27562148

RESUMO

Interfaces are essential in electrochemical processes, providing a critical nanoscopic design feature for composite electrodes used in Li-ion batteries. Understanding the structure, wetting and mobility at nano-confined interfaces is important for improving the efficiency and lifetime of electrochemical devices. Here we use a Surface Forces Apparatus to quantify the initial wetting of nanometre-confined graphene, gold and mica surfaces by Li-ion battery electrolytes. Our results indicate preferential wetting of confined graphene in comparison with gold or mica surfaces because of specific interactions of the electrolyte with the graphene surface. In addition, wetting of a confined pore proceeds via a profoundly different mechanism compared with wetting of a macroscopic surface. We further reveal the existence of molecularly layered structures of the confined electrolyte. Nanoscopic confinement of less than 4-5 nm and the presence of water decrease the mobility of the electrolyte. These results suggest a lower limit for the pore diameter in nanostructured electrodes.

7.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 31(5): 1168-71, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25764744

RESUMO

Skeletal muscle possesses a remarkable ability for its regeneration and injured tissue repair. This ability depends on the activity and contributions of muscle satellite cells. Proliferating satellite cells, termed myogenic precursor cells or myoblasts, are activated and driven out of their quiescent state upon muscle injury. In this summary, we present a review to summarize the molecular regulation in skeletal satellite cells to light on the satellite cells' self-renewal mechanism.


Assuntos
Regeneração , Células Satélites de Músculo Esquelético/citologia , Proliferação de Células , Humanos , Músculo Esquelético , Lesões dos Tecidos Moles
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