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1.
Respir Med Case Rep ; 50: 102045, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38868162

RESUMEN

Introduction: Foreign bodies in the airways can cause significant morbidity and mortality. If emergency personnel are unable to clear an airway obstruction frequently results in cardiac arrest. Patient concerns: A 78-year-old man developed a persistent cough and dyspnoea after consuming alcohol. Fiberoptic bronchoscopy was performed, revealing complete blockage of the main airways on both sides by fish. Diagnosis: Endotracheal foreign body. Interventions: The foreign body was removed with an endotracheal tube under the guidance of a fiberoptic bronchoscope. Outcomes: The airway foreign body had been successfully removed and the man recovered uneventfully. Conclusion: When repeated attempts to extract airway foreign bodies under the guidance of bronchoscopy have failed, endotracheal intubation can be considered as a viable alternative in emergency situations.

2.
Materials (Basel) ; 17(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38893835

RESUMEN

In this paper, the possibility of retreated lithium slag (RTLS) with a high content of alkali, sulfate and fluoride as a partial replacement for fly ash (FA) to produce autoclaved aerated concrete (AAC) was investigated. The influence of the RTLS dosage on the AAC performance were examined. The composition and microstructure of hydrates as well as the microstructure of the RTLS-FA-based AAC compositions were determined by XRD, FTIR, TG-DSC and SEM. The results illustrated that the incorporation of RTLS changed the crystal structure and the microstructure of the tobermorite. With increased RTLS contents, the morphology of tobermorite was changed, and the grass-like tobermorite gradually transformed into network-like tobermorite. The newly formed tobermorite improved the mechanical performance of the AAC. Compared with the RTLS10, the content of tobermorite in the RTLS30 increased by 8.6%.

3.
Huan Jing Ke Xue ; 45(1): 594-605, 2024 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-38216508

RESUMEN

The pollution control of tetracycline antibiotics in the environment has become a hot topic, and biochar adsorption has become an important technology to remove organic pollutants. Pyrolytic biochars (BC400, BC500, and BC600) were prepared from corn straw and then were modified by KOH to obtain KBC400, KBC500, and KBC600. Among them, KBC400 was selected for secondary pyrolysis activation at 400-600℃ to obtain AKBC400, AKBC500, and AKBC600. The structure characteristics and surface properties of AKBC were also characterized. The adsorption kinetics and thermodynamic characteristics of oxytetracycline hydrochloride (OTC) in the solution by AKBC were investigated using batch experiments. Compared to that of BC400, the specific surface area and pore structure of AKBC were significantly improved, and the aromaticity was also enhanced, resulting in the notable enhancement of the adsorption capacities for OTC. The pseudo-second-order kinetics model could better fit the adsorption process, and AKBC500 had the largest adsorption rate constant and capacity. Both the intraparticle diffusion and film diffusion were the rate-limiting steps. The Langmuir, Freundlich, and Temkin models could fit the adsorption isotherms perfectly. The adsorption of OTC on AKBC was a spontaneous, endothermic, and entropy-increasing process by both physisorption and chemisorption. The pH values in the range of 3.0-7.0 were favorable for the adsorption of OTC by AKBC. The adsorption capacity decreased with the humic acid concentration over 10 mg·L-1. The adsorption mechanism of OTC by AKBC involved pore filling, hydrogen bonding, π-π conjugation, cation-π bond, and strong electrostatic effect. AKBC still had good reusability for OTC removal after five times of regeneration. The obtained AKBC is a potential adsorbent for OTC removal from water due to the good pore structure, high adsorption capacity, and stable adsorption effect.


Asunto(s)
Oxitetraciclina , Contaminantes Químicos del Agua , Zea mays , Agua , Adsorción , Antibacterianos , Carbón Orgánico/química , Cinética , Contaminantes Químicos del Agua/análisis
4.
Langmuir ; 39(51): 19008-19015, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38079624

RESUMEN

Olivine dissolution plays an important role in environmental science and technology, from controlling global element circulation to carbon capture for climate change mitigation. Most studies have been focused on investigating its dissolution rates by monitoring chemical effluent changes under various conditions. However, only by observation of surface reactivity can we unravel the actual mechanism (s) of dissolution. Here, we studied the dissolution of an olivine (010) plane in a flow-through reaction cell with an acidic solution, a surface-controlled regime, and far-from-equilibrium conditions. Direct mineral surface topography measurements using vertical scanning interferometry and atomic force microscopy allowed for quantitative analyses of the spatial and temporal changes in the dissolution rate. The (010) plane dissolved discontinuously in time for different surface sites, resulting in a heterogeneously distributed rate map. Pits with different depths showed opposite dissolution rate distributions from the dislocation center to further out from the etch pit. Based on the step-wave model, we propose a mechanism of dissolution that is governed by the competition between Gibbs free energy of the dissolution process, ΔG, and the critical free energy of the opening of etch pits, i.e., ΔGcrit. The migration of step waves, the distribution of surface defects, the strain field of etch pits, and other dynamic elements, resulting in the instantaneous change of ΔGcrit on the surface, are important factors leading to the discontinuous dissolution of crystal materials. This discontinuous dissolution provides new insight into the guidance of crystalline mineral applications and the prediction of material properties regarding mineral dissolution variation.

5.
Sci Rep ; 13(1): 11125, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37429893

RESUMEN

Gastric cancer remains one of the most prevalent tumors worldwide and peritoneal metastasis is responsible for approximately 60% of death in advanced gastric cancer patients. However, the underlying mechanism of peritoneal metastasis is poorly understood. We have established organoids derived from malignant ascites (MA) of gastric cancer patients and noticed that MA supernatant could strongly increase the colony formation of organoids. Thus, we realized the interaction between exfoliated cancer cells (ECCs) and liquid tumor microenvironment contributes to peritoneal metastasis. Further, we designed a medium component control test which proved that exosomes derived from MA could not enhance the growth of organoids. Using Immunofluorescence and confocal imaging as well as dual-luciferase reporter assay, our data showed WNT signaling pathway was upregulated by high concentrations of WNT ligands (wnt3a and wnt5a), which was verified by ELISA. Besides, suppressing WNT signaling pathway diminished the growth promoting function of MA supernatant. This result implicated WNT signaling pathway as a potential therapeutic target for peritoneal metastasis of gastric cancer.


Asunto(s)
Neoplasias Peritoneales , Neoplasias Gástricas , Humanos , Vía de Señalización Wnt , Microambiente Tumoral , Peritoneo
6.
Nat Commun ; 14(1): 3944, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37402751

RESUMEN

Noble metals have been extensively employed in a variety of hydrotreating catalyst systems for their featured functionality of hydrogen activation but may also bring side reactions such as undesired deep hydrogenation. It is crucial to develop a viable approach to selectively inhibit side reactions while preserving beneficial functionalities. Herein, we present modifying Pd with alkenyl-type ligands that forms homogeneous-like Pd-alkene metallacycle structure on the heterogeneous Pd catalyst to achieve the selective hydrogenolysis and hydrogenation. Particularly, a doped alkenyl-type carbon ligand on Pd-Fe catalyst is demonstrated to donate electrons to Pd, creating an electron-rich environment that elongates the distance and weakens the electronic interaction between Pd and unsaturated C of the reactants/products to control the hydrogenation chemistry. Moreover, high H2 activation capability is maintained over Pd and the activated H is transferred to Fe to facilitate C-O bond cleavage or directly participate in the reaction on Pd. The modified Pd-Fe catalyst displays comparable C-O bond cleavage rate but much higher selectivity (>90%) than the bare Pd-Fe (<50%) in hydrotreating of diphenyl ether (DPE, modelling the strongest C-O linkage in lignin) and enhanced ethene selectivity (>90%) in acetylene hydrogenation. This work sheds light on the controlled synthesis of selective hydrotreating catalysts via mimicking homogeneous analogues.

7.
Adv Sci (Weinh) ; 10(16): e2205557, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36988448

RESUMEN

Biomass is considered as a promising source to fabricate functional carbon materials for its sustainability, low cost, and high carbon content. Biomass-derived-carbon materials (BCMs) have been a thriving research field. Novel structures, diverse synthesis methods, and versatile applications of BCMs have been reported. However, there has been no recent review of the numerous studies of different aspects of BCMs-related research. Therefore, this paper presents a comprehensive review that summarizes the progress of BCMs related research. Herein, typical types of biomass used to prepare BCMs are introduced. Variable structures of BCMs are summarized as the performance and properties of BCMs are closely related to their structures. Representative synthesis strategies, including both their merits and drawbacks are reviewed comprehensively. Moreover, the influence of synthetic conditions on the structure of as-prepared carbon products is discussed, providing important information for the rational design of the fabrication process of BCMs. Recent progress in versatile applications of BCMs based on their morphologies and physicochemical properties is reported. Finally, the remaining challenges of BCMs, are highlighted. Overall, this review provides a valuable overview of current knowledge and recent progress of BCMs, and it outlines directions for future research development of BCMs.

8.
Sci Adv ; 9(4): eabq1369, 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36706186

RESUMEN

Single-ion selectivity with high precision has long been pursued for fundamental bioinspired engineering and applications such as in ion separation and energy conversion. However, it remains a challenge to develop artificial ion channels to achieve single-ion selectivity comparable to their biological analogs, especially for high Na+/K+ selectivity. Here, we report an artificial sodium channel by subnanoconfinement of 4'-aminobenzo-15-crown-5 ethers (15C5s) into ~6-Å-sized metal-organic framework subnanochannel (MOFSNC). The resulting 15C5-MOFSNC shows an unprecedented Na+/K+ selectivity of tens to 102 and Na+/Li+ selectivity of 103 under multicomponent permeation conditions, comparable to biological sodium channels. A co-ion-responsive single-file transport mechanism in 15C-MOFSNC is proposed for the preferential transport of Na+ over K+ due to the synergetic effects of size exclusion, charge selectivity, local hydrophobicity, and preferential binding with functional groups. This study provides an alternative strategy for developing potential single-ion selective channels and membranes for many applications.

9.
J Hazard Mater ; 439: 129620, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-35908397

RESUMEN

The chlorine evolution mechanism remains unclear during the thermal treatment of CaCl2/Ca(OH)Cl-containing solid waste. In this paper, we have conducted both experimental investigation and density functional theory (DFT) calculation to elucidate the mechanism of pyro-hydrolysis of CaCl2 with and without SiO2 in the temperature ranges of 400-900 °C. It was determined that pyro-hydrolysis of CaCl2 alone generated a maximum of 12% HCl by decomposition into Ca(OH)Cl, which is a stable intermediate that can be reverted to CaCl2 at 800 °C. Upon the addition of SiO2 at an equimolar ratio to CaCl2, the HCl release extent was accelerated to 50% at 900 °C. Both experiments and DFT calculations prove that the added SiO2 can promote the dissociation of water molecules which provides hydroxyl ions that enable the conversion of CaCl2 into Ca(OH)Cl at low temperatures. The resulting Ca(OH)Cl can also quickly react with SiO2 to form Cl-bearing silicates such as Ca2SiO3Cl2 and Ca3SiO4Cl2 with weakened CaCl bond that are relatively easy to cleave into Cl-free CaSiO3 and HCl(g) from 800 °C.

10.
IBRO Neurosci Rep ; 12: 355-365, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35746976

RESUMEN

In adults, γ-aminobutyric acid (GABA) type A receptor (GABAAR)-mediated inhibition depends on the maintenance of low intracellular chloride anion concentration through neuron-specific potassium-chloride cotransporter-2 (KCC2). KCC2 has been widely reported to have a plasticity change during the course of epilepsy development, with an early downregulation and late recovery in neuronal cell membranes after epileptic stimulation, which facilitates epileptiform burst activity. Furosemide is a clinical loop diuretic that inhibits KCC2. Here, we first confirmed that furosemide pretreatment could effectively prevented convulsant stimulation-induced neuronal membrane KCC2 downregulation in the hippocampus in both in vivo and in vitro cyclothiazide-induced seizure model. Second, we verified that furosemide pretreatment rescued KCC2 function deficits, as indicated by E GABA depolarizing shift and GABAAR inhibitory function impairment induced via cyclothiazide treatment. Further, we demonstrated that furosemide also suppressed cyclothiazide-induced epileptiform burst activity in cultured hippocampal neurons and lowered the mortality rate during acute seizure induction. Overall, furosemide prevents membrane KCC2 downregulation during acute seizure induction, restores KCC2-mediated GABA inhibition, and interrupts the progression from acute seizure to epileptogenesis.

11.
Nanomicro Lett ; 14(1): 107, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35438351

RESUMEN

HIGHLIGHTS: Metal-organic frameworks (MOFs) are used to directly initiate the gelation of graphene oxide (GO), producing MOF/rGO aerogels. The ultralight magnetic and dielectric aerogels show remarkable microwave absorption performance with ultralow filling contents. The development of a convenient methodology for synthesizing the hierarchically porous aerogels comprising metal-organic frameworks (MOFs) and graphene oxide (GO) building blocks that exhibit an ultralow density and uniformly distributed MOFs on GO sheets is important for various applications. Herein, we report a facile route for synthesizing MOF/reduced GO (rGO) aerogels based on the gelation of GO, which is directly initiated using MOF crystals. Free metal ions exposed on the surface of MIL-88A nanorods act as linkers that bind GO nanosheets to a three-dimensional porous network via metal-oxygen covalent or electrostatic interactions. The MOF/rGO-derived magnetic and dielectric aerogels Fe3O4@C/rGO and Ni-doped Fe3O4@C/rGO show notable microwave absorption (MA) performance, simultaneously achieving strong absorption and broad bandwidth at low thickness of 2.5 (- 58.1 dB and 6.48 GHz) and 2.8 mm (- 46.2 dB and 7.92 GHz) with ultralow filling contents of 0.7 and 0.6 wt%, respectively. The microwave attenuation ability of the prepared aerogels is further confirmed via a radar cross-sectional simulation, which is attributed to the synergistic effects of their hierarchically porous structures and heterointerface engineering. This work provides an effective pathway for fabricating hierarchically porous MOF/rGO hybrid aerogels and offers magnetic and dielectric aerogels for ultralight MA.

12.
Psychol Res ; 86(3): 737-745, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34021401

RESUMEN

Using a reading comprehension task, we explored whether body postures would influence mind wandering, a universal internally self-generated activity. Specifically, participants were instructed to perform a reading comprehension task under three postural conditions (lying supine, sitting, and standing upright). Probe-caught technique with prompts presented at irregular intervals was adapted to measure the frequency of mind wandering. Self-caught method was used to measure the meta-awareness of mind wandering by self-reports. Results indicated that the radio of mind wandering was significantly greater in lying than standing and sitting, but the meta-awareness of it was not different among three postures. Moreover, the reading performance, an indirect indicator of executive control, decreased in lying compared to standing and sitting. We suggested that the increase of mind wandering in lying posture may due to the dysfunction of executive control, which also results in the redistribution of cognitive resources. Suggestions for future research are proposed.


Asunto(s)
Atención , Lectura , Función Ejecutiva , Humanos , Postura , Autoinforme
13.
Dalton Trans ; 50(15): 5244-5250, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-33881082

RESUMEN

By regulating the solvent used for synthesis, two porous Ni-MOFs, namely {[Ni3(BTC)2(TPT)2/3(H2O)4.08(MeOH)0.92]·2DMF·0.5H2O·0.5MeOH}n (1) and {[Ni3(BTC)2(TPT)2(H2O)6]·6DMF}n (2) (H3BTC = 1,3,5-benzenetricarboxylic acid, TPT = 2,4,6-tris(pyridin-4-yl)-1,3,5-triazine, DMF = N,N-dimethylformamide, and MeOH = methanol) were obtained. Compound 1 reveals a rigid 3D framework, while compound 2 shows a flexible 3-fold interpenetrated framework. Compound 1 exhibits a selective adsorption of CO2 due to the sieving effect of the rigid framework containing two types of cages with small apertures. Noteworthily, the flexible compound 2 displays an obviously guest-induced structural transformation. The desolvated compound 2 reveals a much higher capacity toward CO2 and n-C4H10 than those of N2 CH4, C2H6 and C3H8.

14.
Sci Total Environ ; 780: 146600, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33774305

RESUMEN

Phosphogypsum (PG) is an industry solid waste produced from phosphoric acid manufacture. To reduce environmental pollution of the PG, H2C2O4 was employed to purify it, which then can be used for cement production. The optimal concentration of H2C2O4 for PG purification was determined. In addition, differential thermal analysis (DTA), X-ray photoelectron spectroscopy (XPS) and X-ray fluorescence (XRF) were used to determine the removal of phosphate impurity in PG. The effects of purified PG on cement hydration and the environmental implications were also investigated. The results demonstrate that H2C2O4 can remove the intercrystalline phosphate impurities by destroying the part of the crystal structure of gypsum. With the best treatment concentration of 1% H2C2O4, 77.7% of phosphate impurity (as P2O5) was removed from PG, which subsequently shortened the final setting time down to 220 min and successfully met the national standard (GB 175-1999). Portland cement prepared by the 1% H2C2O4 treated PG possessed a comparable 3d compressive strength of 20.8 MPa and a 28d compressive strength of 44.6 MPa. It is concluded that PG purified by 1% H2C2O4 treatment can be used for cement production. Meanwhile, this H2C2O4 treatment can effectively reduce the environmental pollution from PG and offer a sustainable method for the utilization of PG.

15.
ACS Nano ; 15(1): 1240-1249, 2021 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-33332960

RESUMEN

Construction of nanofluidic devices with an ultimate ion selectivity analogue to biological ion channels has been of great interest for their versatile applications in energy harvesting and conversion, mineral extraction, and ion separation. Herein, we report a three-dimensional (3D) sub-1 nm nanofluidic device to achieve high monovalent metal ion selectivity and conductivity. The 3D nanofluidic channel is constructed by assembly of a carboxyl-functionalized metal-organic framework (MOF, UiO-66-COOH) crystals with subnanometer pores into an ethanediamine-functionalized polymer nanochannel via a nanoconfined interfacial growth method. The 3D UiO-66-COOH nanofluidic channel achieves an ultrahigh K+/Mg2+ selectivity up to 1554.9, and the corresponding K+ conductivity is one to three orders of magnitude higher than that in bulk. Drift-diffusion experiments of the nanofluidic channel further reveal an ultrahigh charge selectivity (K+/Cl-) up to 112.1, as verified by the high K/Cl content ratio in UiO-66-COOH. The high metal ion selectivity is attributed to the size-exclusion, charge selectivity, and ion binding of the negatively charged MOF channels. This work will inspire the design of diverse MOF-based nanofluidic devices for ultimate ion separation and energy conversion.

16.
Waste Manag ; 120: 608-615, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33172739

RESUMEN

Effective liberation of chlorine (Cl) as a recoverable product such as hydrochloric acid is crucial for the clean disposal of massive Cl-bearing industrial solid waste. This study aims to clarify the evolution of Cl upon the pyrohydrolysis of CaCl2 waste. Particularly, the use of silica and MgCl2 to promote the breakage of Ca-Cl bonds to release HCl gas has been investigated, via synchrotron X-ray absorption spectroscopy (XAS). As confirmed, in the presence of silica, the pyrohydrolysis of CaCl2 commences from 800 °C, lower than the minimum temperature predicted based on the existing thermodynamic database. The attraction of Ca2+ by SiO44- breaks the Ca-Cl bond successfully. The addition of Mg2+ can also improve the HCl regeneration extent to nearly 100%. Upon the addition of Mg2+, a structure of Ca-O-Mg-Cl is very likely to form, in which the second coordination shell of Ca2+ is occupied by both Cl- and Mg2+. Consequently, the incorporated Mg2+ bonds with Cl-, "pushing" the Ca2+ in the third shell further away, leading to a distorted and less crystalline silicate matrix from which the liberation of Cl- is easier. The Cl K-edge XANES shows that the reaction residues feature a unique, long-range multi-scattering phenomenon; this differs from the fully molten Cl-bearing glasses that bear a high similarity with CaCl2.


Asunto(s)
Calcio , Cloro , Hidrólisis , Cloruro de Magnesio , Sincrotrones , Espectroscopía de Absorción de Rayos X
17.
ChemSusChem ; 13(24): 6660-6667, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33052035

RESUMEN

The fundamental question of whether CO2 can react with steam at high temperatures in the absence of electrolysis or high pressures is answered. These two gases are commonly co-present as industrial wastes. Herein, a simple experiment by flowing CO2 and steam through a CaCl2 matrix at 500-1000 °C and atmospheric pressure was designed. Comprehensive characterizations and density functional theory calculations were conducted. Meanwhile, this study aims to recover HCl from CaCl2 via a low-emission oxy-pyrohydrolysis process. As confirmed, CO2 and steam interact strongly on the CaCl2 surface, leading to an explicit formation of CaCO3 /CaO and a nearly complete release of HCl. This is mainly contributed to a halved energy required for the splitting of H2 O, resulting from the formation of a bicarbonate-like structure to replace Cl- out of CaCl2 , an otherwise industrial waste, whilst an important dopant for carbon capture, utilization and storage, and medium for electrochemical synthesis.

18.
Brain Sci ; 10(9)2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-32906625

RESUMEN

Steady-state visual evoked potential (SSVEP) is a periodic response to a repetitive visual stimulus at a specific frequency. Currently, SSVEP is widely treated as an attention tag in cognitive activities and is used as an input signal for brain-computer interfaces (BCIs). However, whether SSVEP can be used as a reliable indicator has been a controversial issue. We focused on the independence of SSVEP from frequency allocation and number of stimuli. First, a cue-target paradigm was adopted to examine the interaction between SSVEPs evoked by two stimuli with different frequency allocations under different attention conditions. Second, we explored whether signal strength and the performance of SSVEP-based BCIs were affected by the number of stimuli. The results revealed that no significant interaction of SSVEP responses appeared between attended and unattended stimuli under various frequency allocations, regardless of their appearance in the fundamental or second-order harmonic. The amplitude of SSVEP suffered no significant gain or loss under different numbers of stimuli, but the performance of SSVEP-based BCIs varied along with duration of stimuli; that is, the recognition rate was not affected by the number of stimuli when the duration of stimuli was long enough, while the information transfer rate (ITR) presented the opposite trend. It can be concluded that SSVEP is a reliable tool for marking and monitoring multiple stimuli simultaneously in cognitive studies, but much caution should be taken when choosing a suitable duration and the number of stimuli, in order to achieve optimal utility of BCIs in the future.

19.
Biochem Biophys Res Commun ; 532(3): 489-495, 2020 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-32892950

RESUMEN

The GABAA receptor (GABAAR) is the main inhibitory receptor in the adult mammalian brain. GABAAR function is dependent on its expression, distribution, and the chloride (Cl-) transmembrane gradient, which is determined by the potassium-chloride cotransporter 2 (KCC2) in the adult brain. KCC2 and GABAAR are downregulated in an activity-dependent manner during seizure induction. Functionally, KCC2 and GABAAR are closely related membrane proteins which modulate GABAergic inhibition. However, it remains unclear how their downregulation during seizure induction is coordinated. This study aimed to assess this interaction. Our results revealed that KCC2 and GABAAR were simultaneously downregulated in both in vivo and in vitro seizure models induced by the convulsant cyclothazide (CTZ), which was at least partly due to structural coupling in hippocampal neuronal membranes. Immunohistochemistry revealed colocalization of gephyrin with KCC2 and co-immunoprecipitation exhibited a direct coupling between GABAAR α1-subunit and KCC2 protein in hippocampal cell membranes. KCC2 specific short hairpin RNA (KCC2-shRNA) was employed to specifically reduce the expression of KCC2 in cultured hippocampal neurons. This resulted in a significant reduction in KCC2-independent GABAergic miniature inhibitory post-synaptic current (mIPSC) amplitude in shKCC2-transfected neurons. Further, pre-treatment with furosemide, a KCC2 inhibitor, during CTZ stimulation followed by washout significantly prevented convulsant stimulation-induced membrane KCC2 downregulation and significantly attenuated GABAAR downregulation concomitant with recovery of suppressed KCC2-independent GABAergic mIPSC amplitude. Our results suggest that the coordinated downregulation of KCC2 and GABAAR during seizure induction exerts a strong functional impact on GABAAR, highlighting an important regulatory mechanism in epilepsy.


Asunto(s)
Receptores de GABA-A/metabolismo , Convulsiones/metabolismo , Simportadores/metabolismo , Animales , Benzotiadiazinas/toxicidad , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Técnicas In Vitro , Potenciales Postsinápticos Inhibidores/efectos de los fármacos , Masculino , Potenciales Postsinápticos Miniatura/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de GABA-A/genética , Convulsiones/inducido químicamente , Simportadores/antagonistas & inhibidores , Simportadores/genética , Cotransportadores de K Cl
20.
J Hazard Mater ; 395: 122696, 2020 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-32330778

RESUMEN

The recovery of value-added materials from coal ash waste is of highly economic value and sustainable significance. However, researches on the synthesis of defect-engineering nanomaterials from coal ash are still blank. Herein, iron oxide (Fe1.72Al0.28O3, simplified as FAO) nanoflakes were successfully synthesized from a brown coal fly ash (BCFA) waste. The obtained FAO nanoflakes possess a round-shape morphology with a diameter of around 300 nm and 50 nm in thickness. With the progress of hydrothermal treatment, the impure Al3+ gradually replaced part of the Fe3+ in the α-Fe2O3 crystal. Specifically, Al3+ was preferentially adsorbed on the (001) facet, hindering the growth of Fe3+ on the [001] direction and thus causing the flattening of the resultant FAO. The introduced Al3+ also serves as the disordered defects on the hematite surface, leading to decreased crystal parameters for hematite, the formation of a compact first shell and a reduced periodical symmetry for the central cation Fe3+. The defects were also found to significantly improve the adsorption capacity of the resultant FAO for Cr(VI), As(V), As(III) and Congo red in waste water, with the maximum adsorption capacity of 68.3, 80.6, 61.1 and 213.8 mg g-1, respectively. Cyclic tests also confirmed a relatively strong stability for the as-synthesised adsorbents.

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