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1.
Nat Commun ; 14(1): 7971, 2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38042894

RESUMEN

Ketamine produces rapid antidepressant effects at sub-anesthetic dosage through early and sustained activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs), however, the exact molecular mechanism still remains unclear. Transmembrane AMPAR regulatory protein-γ8 (TARP-γ8) is identified as one of AMPAR auxiliary subunits, which controls assemblies, surface trafficking and gating of AMPARs. Here, we show that ketamine rescues both depressive-like behaviors and the decreased AMPARs-mediated neurotransmission by recruitment of TARP-γ8 at the postsynaptic sites in the ventral hippocampus of stressed male mice. Furthermore, the rapid antidepressant effects of ketamine are abolished by selective blockade of TARP-γ8-containing AMPAR or uncoupling of TARP-γ8 from PSD-95. Overexpression of TARP-γ8 reverses chronic stress-induced depressive-like behaviors and attenuation of AMPARs-mediated neurotransmission. Conversely, knockdown of TARP-γ8 in excitatory neurons prevents the rapid antidepressant effects of ketamine.


Asunto(s)
Ketamina , Ratones , Animales , Masculino , Ketamina/farmacología , Receptores AMPA/fisiología , Neuronas/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Antidepresivos/farmacología
2.
Materials (Basel) ; 15(3)2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35160747

RESUMEN

We report synthesis, crystal structure, and physical properties of Sr2Cr2AsO3. The new compound crystallizes in a Sr2GaO3CuS-type structure with two distinct Cr sites, Cr(1) in the perovskite-like block layers of "Sr3Cr2O6" and Cr(2) in the ThCr2Si2-type layers of "SrCr2As2". An inter-block-layer charge transfer is explicitly evidenced, which dopes electrons in the CrO2 planes and simultaneously dopes holes into the CrAs layers. Measurements of electrical resistivity, magnetization, and specific heat, in combination with density-functional theoretical calculations, indicate that the title material is an antiferromagnetic metal. The Cr(2) magnetic moments in the CrAs layers order at 420 K, while the Cr(1) spins in the CrO2 planes show quasi-two-dimensional magnetism with long-range ordering below 80 K. Both Néel temperatures are significantly reduced, compared with those of the cousin material Sr2Cr3As2O2, probably due to the intrinsic charge-carrier doping. Complex re-entrant magnetic transitions with a huge magnetic hysteresis were observed at low temperatures.

3.
Huan Jing Ke Xue ; 42(3): 1131-1140, 2021 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-33742909

RESUMEN

Short-chain chlorinated paraffins are persistent organic pollutants, and chlorinated paraffins were widely used as sizing agent in the paper industry. In order to investigate the levels and risk assessment of short-chain and medium-chain chlorinated paraffins in the paper mill plant, the surface soil and soil of different depths were collected.The concentrations, congener group profiles of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in soil were determined by two-dimensional gas chromatography coupled with electron capture-negative ion mass spectrometry. The SCCPs and MCCPs concentrations were 42-3853 ng·g-1 and 34-2091 ng·g-1. The chlorine contents were 59.9%-61.9% and 48.7%-52.8%. The concentrations of SCCPs and MCCPs were different in the soil collected in different sampling site. The concentration of SCCPs and MCCPs were relatively higher in soil of sewage treatment area and coating area. The CP levels in soil from the paper mill plant were at a high level compared with those in other regions. C10Cl6-7 and C14-15Cl5 were the main congener groups in most soil samples. The results of principal component analysis showed that the CP52 commercial products may be sources of SCCPs and MCCPs in the soil. The risk quotient (RQ) for SCCPs and MCCPs were assessed in soil of paper mill plant. The results showed that the RQ values for SCCPs in soil ranged from 0.01 to 0.73 which are the medium risk, and the RQ values for MCCPs in soil ranged from 0 to 0.07, which are the low risk. The human exposure values of children and adults are lower than TDI[10 µg·(kg·d)-1] in both cases. The health risks caused by non-dietary exposure under paper mill area are low.


Asunto(s)
Hidrocarburos Clorados , Parafina , Niño , China , Monitoreo del Ambiente , Humanos , Hidrocarburos Clorados/análisis , Parafina/análisis , Medición de Riesgo , Suelo
4.
Huan Jing Ke Xue ; 41(12): 5352-5361, 2020 Dec 08.
Artículo en Chino | MEDLINE | ID: mdl-33374051

RESUMEN

A passive air sampler was used to monitor the concentration and contamination profile of 18 polychlorinated biphenyls (PCBs) in the atmosphere over the urban and industrial area of Gaolan, a city in northwest China, during the non-heating and heating seasons of 2018, and the sources, pollutant transport, and the health risks of PCB exposure were analyzed and assessed using principle component analysis, trajectory modeling, and inhalation exposure modeling. The atmospheric concentration in the study area ranged from 110.2 to 429.9 pg·m-3, and the highest average concentration was found at the industrial estate. Tetra-PCBs and penta-PCBs were the dominant homologue groups, and the percentage of tetra-PCBs increased in the heating season. Combustion and industrial thermal processes, PCB-containing electrical equipment, and the combined source of volatilization from paint, combustion, and industrial thermal processes were considered to be the main sources, and the source of combustion and industrial thermal processes contributed the largest proportion of PCBs at 40.8%. Largely, the emission of UP-PCBs would significantly influence PCB pollution in the study area. Trajectory analysis results illustrated that PCBs emitted from sources in the study area would be transmitted to Lanzhou City atmospherically; local pollution would be the main source of PCBs contamination in the study area during the non-heating season, while the atmospheric input of PCBs transmitted from the northwest region would be another source during the heating season. Health risk analysis showed that the non-cancer risk of PCBs exposure was low in all age groups; however, lifetime cancer risks exceeded 10-6. PCBs emitted from combustion and industrial thermal processes sources would have a strong impact on resident exposure to PCBs, and adverse health effects would be caused due to long-term inhalation exposure of the inhabitants to PCBs contamination in the study area.


Asunto(s)
Contaminantes Atmosféricos , Bifenilos Policlorados , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , China , Ciudades , Monitoreo del Ambiente , Bifenilos Policlorados/análisis
5.
Huan Jing Ke Xue ; 41(2): 510-519, 2020 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-32608710

RESUMEN

PCDD/Fs emission inventory is the basis for PCDD/Fs control, research on environmental fate behavior, and health risk assessment. In the present study, based on officially released PCDD/Fs emissions inventory for each industry in China in 2004, we estimated atmospheric PCDD/Fs emissions by sector in various provinces in 2016 by combining the emission intensity in the "Identification and Quantification of PCDD/Fs Emission Standards Toolkit" released by the United Nations Environment Program (UNEP) in 2013. Subsequently, using different gridding data for various sectors as surrogate data, we established atmospheric gridded emission inventory (1/4°×1/4° latitude by longitude) for PCDD/Fs in China. Finally, the uncertainty of PCDD/Fs emission inventory was analyzed. Results show that the atmospheric emissions of PCDD/Fs in China in 2016 were 10366 g, which was about two times higher than that in 2004. From the perspective of the emission sector, metal smelting is the largest emitter of PCDD/Fs in China, which released 5333 g, followed by waste incineration (2469 g), heating and power generation (1290 g), and mineral production (933 g). These four sectors accounted for 97% of China's total PCDD/Fs emissions. In spatial terms, China's atmospheric PCDD/Fs emissions are mainly concentrated in the Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta regions. PCDD/Fs emissions from the Beijing-Tianjin-Hebei and Yangtze River Delta regions originate mainly from steel smelting, and that from the Pearl River Delta region is mainly due to waste incineration.

6.
Huan Jing Ke Xue ; 40(2): 558-566, 2019 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-30628317

RESUMEN

Passive air samplers (PAS-PUF) and passive dry deposition (PAS-DD) samplers were applied in the Bosten Lake watershed located in Xinjiang to estimate the atmospheric concentrations and dry deposition fluxes for 15 US EPA priority polycyclic aromatic hydrocarbons (PAHs) during a heating period in 2016 and no-heating period in 2017, respectively. The results showed that the atmospheric PAHs concentrations in the Bosten oasis area ranged from 6.38 ng·m-3 to 245.43 ng·m-3 during the heating period and 2.33 ng·m-3 to 74.76 ng·m-3 during the non-heating period. The highest atmospheric PAHs concentrations were found in the residential area, followed by regions near Bosten Lake and Tazhong. The atmospheric dry deposition fluxes of PAHs in the Bosten Lake watershed ranged from 0.45 µg·(m2·d)-1 to 18.10 µg·(m2·d)-1 during the heating period and 0.25 µg·(m2·d)-1to 8.15 µg·(m2·d)-1 during the non-heating period. During the heating period, the atmospheric dry deposition fluxes in the residential area were significantly higher than those in the regions near Bosten Lake and Tazhong. However, the atmospheric PAHs dry deposition flux in Tazhong was much higher than that in other sites during the heating and no-heating periods. In general, the atmospheric PAHs dry deposition fluxes during the heating period were significantly higher than those during the non-heating period. PAH composition for the atmosphere and dry deposition were dominated by 3 and 4 ring congeners, especially by phenanthrene, fluorine, fluoranthene, and pyrene during two sampling periods. In addition, the congener diagnostic ratio shows that coal and biomass combustion were possible sources of atmospheric PAHs in the Bosten Lake watershed. The forward and backward trajectory analysis based on the HYSPLIT model demonstrated that the higher atmospheric PAH emissions from the residential area would be transported to Bosten Lake, which can affect the aquatic environment of this lake by dry deposition.

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