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1.
Proc Natl Acad Sci U S A ; 121(14): e2317444121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38527208

RESUMO

Dust loading in West and South Asia has been a major environmental issue due to its negative effects on air quality, food security, energy supply and public health, as well as on regional and global weather and climate. Yet a robust understanding of its recent changes and future projection remains unclear. On the basis of several high-quality remote sensing products, we detect a consistently decreasing trend of dust loading in West and South Asia over the last two decades. In contrast to previous studies emphasizing the role of local land use changes, here, we attribute the regional dust decline to the continuous intensification of Arctic amplification driven by anthropogenic global warming. Arctic amplification results in anomalous mid-latitude atmospheric circulation, particularly a deepened trough stretching from West Siberia to Northeast India, which inhibits both dust emissions and their downstream transports. Large ensemble climate model simulations further support the dominant role of greenhouse gases induced Arctic amplification in modulating dust loading over West and South Asia. Future projections under different emission scenarios imply potential adverse effects of carbon neutrality in leading to higher regional dust loading and thus highlight the importance of stronger anti-desertification counter-actions such as reforestation and irrigation management.

2.
Anal Chem ; 96(14): 5648-5657, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38556994

RESUMO

Nanochannels are a powerful technique for detecting a wide range of biomolecules without labeling. The ion transport phenomena in nanochannel arrays differ from those in single nanochannels and are caused by interchannel communication. This study uses a fully coupled Poisson-Nernst-Planck (PNP) and Navier-Stokes model to investigate ion transport in nanochannel arrays. Instead of being set at a constant value, the surface charge density used in this study is established by the protonation and deprotonation of the silanol groups that are present on the walls of the silicon-based nanochannels. The surface charge density of the nanochannel walls varies with the number of nanochannels, the channel lateral distance, and the background solution properties, which consequently influence the ionic concentration distribution, flow velocity, and electric field strength. For example, in different numbers of nanochannel systems, the ion concentration in nanochannels is not much different, but it is different in reservoirs, especially near the openings of nanochannels. The number of nanochannels and the distance between nanochannels can also affect the formation of electro-convective vortex zones under certain conditions. These findings can aid in optimizing the nanochannel array design by regulating the number and distance of nanochannels and facilitating the construction of solid-state nanochannel arrays with any desired nanochannel dimensions.

3.
Exp Cell Res ; 419(1): 113298, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35961389

RESUMO

Depression is a high-incidence mental illness that seriously affects human health. AQP4 has been reported to be closely associated with depression, while the underlying mechanism is still unclear. This work aimed to investigate the functional role of AQP4 in depression. Depression mouse model was constructed by administration of chronic social defeat stress (CSDS). We found that AQP4 was highly expressed in the hippocampal tissues of CSDS mice. AQP4 knockdown alleviated depression and enhanced the expression of NR2B and PSD95 in CSDS mice. Moreover, primary hippocampal neurons were treated with N-methyl-d-aspartate (NMDA) to induce neuron injury. AQP4 overexpression repressed cell viability and promoted apoptosis of NMDA-treated primary hippocampal neurons. AQP4 up-regulation repressed the expression of NR2B (surface), and enhanced the expression of NR2B (intracellular), P-NR2B, CaMK II and CK2 in the NMDA-treated primary hippocampal neurons. The influence conferred by AQP4 up-regulation was abolished by KN-93 (CaMK II inhibitor) or TBB (CK2 inhibitor) treatment. Rapamycin treatment enhanced the expression of NR2B (surface), and repressed the expression of AQP4, NR2B (intracellular) and P-NR2B in the primary hippocampal neurons by activating autophagy. The activated autophagy alleviated depression in CSDS mice by repressing AQP4 expression. In conclusion, our data demonstrated that autophagy ameliorated depression by repressing AQP4 expression in mice, and AQP4 knockdown promoted membrane trafficking of NR2B and inhibited phosphorylation of NR2B via CaMK II/CK2 pathway. Thus, our work suggests that AQP4 may be a promising molecular target for the development of antidepressant drugs.


Assuntos
N-Metilaspartato , Receptores de N-Metil-D-Aspartato , Animais , Autofagia , Depressão , Hipocampo , Humanos , Camundongos
4.
Proc Natl Acad Sci U S A ; 117(13): 7038-7043, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32179672

RESUMO

Paleoclimate research has built a framework for Earth's climate changes over the past 65 million years or even longer. However, our knowledge of weather-timescale extreme events (WEEs, also named paleoweather), which usually occur over several days or hours, under different climate regimes is almost blank because current paleoclimatic records rarely provide information with temporal resolution shorter than monthly scale. Here we show that giant clam shells (Tridacna spp.) from the tropical western Pacific have clear daily growth bands, and several 2-y-long (from January 29, 2012 to December 9, 2013) daily to hourly resolution biological and geochemical records, including daily growth rate, hourly elements/Ca ratios, and fluorescence intensity, were obtained. We found that the pulsed changes of these ultra-high-resolution proxy records clearly matched with the typical instrumental WEEs, for example, tropical cyclones during the summer-autumn and cold surges during the winter. When a tropical cyclone passes through or approaches the sampling site, the growth rate of Tridacna shell decreases abruptly due to the bad weather. Meanwhile, enhanced vertical mixing brings nutrient-enriched subsurface water to the surface, resulting in a high Fe/Ca ratio and strong fluorescence intensity (induced by phytoplankton bloom) in the shell. Our results demonstrate that Tridacna shell has the potential to be used as an ultra-high-resolution archive for paleoweather reconstructions. The fossil shells living in different geological times can be built as a Geological Weather Station network to lengthen the modern instrumental data and investigate the WEEs under various climate conditions.


Assuntos
Bivalves/química , Bivalves/crescimento & desenvolvimento , Clima Extremo , Paleontologia/métodos , Animais
5.
Opt Express ; 30(3): 3654-3664, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35209619

RESUMO

Observation of a melting layer using a 1.55 µm coherent Doppler lidar (CDL) is first presented during a stratiform precipitation event. Simultaneous radar measurements are also performed by co-located 1.24 cm micro rain radar (MRR) and 10.6 cm Doppler weather radar (DWR). As a well-known bright band in radar reflectivity appears during precipitation, an interesting dark band about 160 m below that in lidar backscattering is observed. Due to the absorption effect, the backscattering from raindrops at 1.55 µm is found much weaker than that at short wavelengths usually used in direct detection lidars. However, the CDL provides additional Doppler information which is helpful for melting layer identification. For example, a spectrum bright band with broadened width and sign conversion of skewness is detected in this case. After a deep analysis of the power spectra, the aerosol and precipitation components are separated. The fall speed of hydrometeors given by CDL is found smaller than that of MRR, with the differences of approximately 0.5 m/s and 1.5 m/s for the snow and rainfall, respectively. To illustrate the influence of absorption effect, simulations of the backscatter coefficient and extinction coefficient of aerosol and rainfall are also performed at the wavelength range of 0.3 ∼ 2.2 µm using the Mie theory.

6.
J Neurochem ; 158(2): 413-428, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33882624

RESUMO

Cognitive deficits are the core feature of schizophrenia and effective treatment strategies are still missing. Previous studies have reported that fisetin promotes long-term potentiation (LTP) and cognitive function in normal rodents and other model animals of neurological diseases. The aim of this study was to assess the effect of fisetin on synaptic plasticity and cognitive deficits caused by a brief disruption of N-methyl-D-aspartate receptors (NMDARs) with dizocilpine (MK-801) during early development in rats. The cognitive performance was examined by the Morris water maze task and a fear conditioning test. Hippocampal synaptic plasticity was investigated by field potential recording. The expression of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) and cognition-related proteins was measured by western blotting. We found that intraperitoneal administration of fisetin rescued hippocampus-dependent spatial and contextual fear memory in MK-801 rats. In parallel with these behavioral results, fisetin treatment in MK-801 rats reversed the impairment of hippocampal LTP. At the molecular level, fisetin treatment selectively increased the phosphorylation and surface expression of AMPA receptor subunit 1 (GluA1) in MK-801-treated rats. Moreover, fisetin restored the phosphorylation levels of calcium-calmodulin-dependent kinaseII (CaMKII), cAMP response element-binding protein (CREB), and the extracellular signal-regulated kinase (ERK1/2) in MK-801-treated rats. Collectively, our findings demonstrate that fisetin treatment can reverse the deficits of hippocampal synaptic plasticity and memory in a male rat model of schizophrenia by restoring the phosphorylation and surface expression of AMPAR GluA1 subunit, suggesting fisetin as a promising therapeutic candidate for schizophrenia-associated cognitive deficits.


Assuntos
Cognição/efeitos dos fármacos , Flavonóis/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Receptores de AMPA/efeitos dos fármacos , Esquizofrenia/tratamento farmacológico , Sinapses/efeitos dos fármacos , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Maleato de Dizocilpina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Medo/efeitos dos fármacos , Medo/psicologia , Injeções Intraperitoneais , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Psicologia do Esquizofrênico
7.
Mol Med ; 27(1): 127, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34654365

RESUMO

OBJECTIVE: D-Serine is a crucial endogenous co-agonist of N-methyl-D-aspartate receptors (NMDARs) in the central nervous system and can affect the function of the brain derived neurotrophic factor (BDNF) system, which plays an essential role in modulating synaptic plasticity. The current study aimed to systematically evaluate the role and mechanisms of D-serine in depressive behavior in nucleus accumbens (NAc). METHODS: D-Serine concentration in the chronic social defeat stress (CSDS) model in NAc was measured using high-performance liquid chromatography (HPLC). The antidepressant-like effects of D-serine were identified using forced swim test (FST) and tail suspension test (TST) in control mice and then assessed in CSDS model. We applied social interaction and sucrose preference tests to identify the susceptibility of CSDS model. Western blotting was further performed to assess the changes of BDNF signaling cascade in NAc after CSDS and D-serine treatment. The BDNF signaling inhibitor (K252a) was also used to clarify the antidepressant-like mechanism of D-serine. Moreover, D-serine effects on synaptic plasticity in NAc were investigated using electrophysiological methods. RESULTS: D-Serine concentration was decreased in depression susceptible mice in NAc. D-Serine injections into NAc exhibited antidepressant-like effects in FST and TST without affecting the locomotor activity of mice. D-Serine was also effective in CSDS model of depression. Moreover, D-serine down-regulated the BDNF signaling pathway in NAc during CSDS procedure. Furthermore, BDNF signaling inhibitor (K252a) enhanced the antidepressant effects of D-serine. We also found that D-serine was essential for NMDARs-dependent long-term depression (LTD). CONCLUSION: D-Serine exerts antidepressant-like effects in mice mediated through restraining the BDNF signaling pathway and regulating synaptic plasticity in NAc.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , Serina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antidepressivos/metabolismo , Antidepressivos/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Depressão/metabolismo , Depressão/fisiopatologia , Membro Posterior/efeitos dos fármacos , Membro Posterior/fisiopatologia , Elevação dos Membros Posteriores/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Núcleo Accumbens/metabolismo , Núcleo Accumbens/fisiologia , Serina/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia
8.
IUBMB Life ; 72(10): 2194-2203, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32780551

RESUMO

Microglia polarization is associated with the pathogenesis of depression. A previous study shows that long non-coding RNA uc.80- is down-regulated in the hippocampus of depressed rats. Thus, this article aims to investigate the role of uc.80- in microglia polarization in depression. We first established depression model rats by chronic unpredictable mild stress (CUMS) regiment. We found that hippocampus of depressed rats exhibited an increase of M1 microglias and a decrease of M2 microglias. uc.80- was down-regulated in hippocampus of depressed rats. Furthermore, the detection of behaviouristics of depressed rats showed that uc.80- overexpression alleviated depression of rats. In addition, uc.80- overexpression promoted M2 polarization of microglias in vivo and in vitro. uc.80- overexpression led to a decrease in apoptosis of hippocampal neurons in vivo and in vitro. In conclusion, our study confirms that lncRNA uc.80- overexpression ameliorates depression in rats by promoting M2 polarization of microglias. Thus, our work suggests that uc.80- may be a target gene for depression treatment.


Assuntos
Depressão/genética , Hipocampo/patologia , Microglia/patologia , RNA Longo não Codificante/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Depressão/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipocampo/fisiologia , Masculino , Microglia/fisiologia , Neurônios/patologia , Neurônios/fisiologia , Ratos Sprague-Dawley , Estresse Psicológico/genética
9.
Int J Biometeorol ; 64(3): 501-512, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31811391

RESUMO

The rising incidence of mosquito-borne diseases is a global concern. Changes in regional climate, due to urbanization and global greenhouse gas concentrations, may affect the ecology of mosquitoes and mosquito-transmitted pathogens. The effects of changes in climate on mosquito population dynamics are complex but critical and urgent for implementing more effective public health policies. This study quantified the impact of urbanization and global climate change on the population of the mosquito species, Culex quinquefasciatus, in the Pearl River Delta region in southern China-an area that has undergone substantial urbanization and is expected to experience changes in climate. This study employed a mechanistic model to simulate mosquito population dynamics under various greenhouse gas emission and land-cover change scenarios based on climate data provided by a state-of-the-art regional climate model. Our results show a 12.6% decrease in the annual mosquito population in newly urbanized areas and a 5.9% increase in the annual mosquito population in existing urban areas. Furthermore, changing climate conditions are projected to cause a 15-17% reduction in the total annual mosquito population; however, the change will not be uniform throughout the year. Peak months exhibit a reduction in population, whereas non-peak months show a significant increase. These findings suggest mosquito control strategies may need to be adjusted to respond to the impacts of urbanization and climate change on mosquito population dynamics to maximize effectiveness. Region specific, quantitative analyses of environmental impacts on mosquito-borne disease ecology, like this study, are needed to provide policy makers with a scientific reference to guide the formation of effective transmission intervention strategies.


Assuntos
Culex , Urbanização , Animais , China , Mudança Climática , Rios
10.
Anal Chem ; 91(7): 4600-4607, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30832478

RESUMO

Ion transport in nanofluidic devices and biological ion channels are highly dependent on the local environmental conditions in the electrolyte solution. Many life processes in living systems are in dynamic electrolyte solutions, and many of them are self-oscillated. Tuning ion transport through a nanofluidic diode by the self-oscillating chemical reactions is demonstrated by modeling the electrokinetic ion transport process with a validated continuum model, which includes the time-dependent Poisson-Nernst-Planck equations for the ionic mass transport of multiple ionic species with both volumetric and surface chemical reactions, and Stokes equations for the flow field. A pH oscillator caused by oscillating chemical reactions (i.e., bromate-sulfite-ferrocyanide system) is added at the tip side of the nanopore to periodically change its surface charge properties, consequently tuning the ion selectivity and ion transport through the nanopore. Results show that both the surface charge density of the nanopore and the electrokinetic ion transport phenomena oscillate simultaneously with the pH oscillation generated by the self-oscillating chemical reactions. The numerical results obtained by our model qualitatively agree with the published experimental observations.


Assuntos
Nanoporos , Nanotecnologia/métodos , Bromatos/química , Ferrocianetos/química , Concentração de Íons de Hidrogênio , Transporte de Íons , Íons/química , Microfluídica , Sulfitos/química
11.
Zhongguo Zhong Yao Za Zhi ; 44(2): 344-349, 2019 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-30989956

RESUMO

The aim of this paper was to investigate the effect of total saponins from Panax japonicus( SPJ) on cognitive decline of natural aging rats and its mechanism. Thirty male SD rats of eighteen month old were randomly divided into three groups: aged group,10 mg·kg~(-1) SPJ-treated group and 30 mg·kg~(-1) SPJ-treated group. The SPJ-treated groups were given SPJ at the dosages of 10 mg·kg~(-1) and 30 mg·kg~(-1),respectively,from the age of 18 to 24 months. Aged group were lavaged the same amount of saline,10 six-month-old rats were used as control group,with 10 rats in each group. The open field test,novel object recognition and Morris water maze were performed to detect the changes of cognitive function in each group. The changes of synaptic transmission of long-term potentiation( LTP) in hippocampal CA1 region were detected by field potential recording. Western blot was used to detect the protein levels of NLRP3,ASC,caspase-1 and the changes of Glu A1,Glu A2,CAMKⅡ,CREB and phosphorylation of CAMKⅡ,CREB in each group.The results showed that SPJ could improve the decline of cognitive function in aging rats,reduce the damage of LTP in the hippocampal CA1 region of aged rats,and decrease the expression of NLRP3,ASC,caspase-1 in aging rats. At the same time,SPJ could enhance the membrane expression of AMPA receptor( Glu A1 and Glu A2),and increase the expression of p-CAMKⅡand p-CREB in aging rats.SPJ could improve cognitive decline of natural aging rats,and its mechanism may be related to regulating NLRP3 inflammasome,thus regulating the membrane expression of AMPA receptor,and enhancing the expression phosphorylation of CAMKⅡ and CREB.


Assuntos
Envelhecimento , Cognição/efeitos dos fármacos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Panax/química , Saponinas/farmacologia , Animais , Região CA1 Hipocampal/fisiologia , Potenciação de Longa Duração , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
12.
J Neuroinflammation ; 15(1): 152, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29776417

RESUMO

BACKGROUND: Epilepsy is a common neurological disorder and is not well controlled by available antiepileptic drugs (AEDs). Inflammation is considered to be a critical factor in the pathophysiology of epilepsy. Sinomenine (SN), a bioactive alkaloid with anti-inflammatory effect, exerts neuroprotective activity in many nervous system diseases. However, little is known about the effect of SN on epilepsy. METHODS: The chronic epilepsy model was established by pentylenetetrazole (PTZ) kindling. Morris water maze (MWM) was used to test spatial learning and memory ability. H.E. staining and Hoechst 33258 staining were used to evaluate hippocampal neuronal damage. The expression of nucleotide oligomerization domain (NOD)-like receptor protein 1 (NLRP1) inflammasome complexes and the level of inflammatory cytokines were determined by western blot, quantitative real-time PCR and enzyme-linked immunosorbent assay (ELISA) kits. RESULTS: SN (20, 40, and 80 mg/kg) dose-dependently disrupts the kindling acquisition process, which decreases the seizure scores and the incidence of fully kindling. SN also increases the latency of seizure and decreases the duration of seizure in fully kindled rats. In addition, different doses of SN block the hippocampal neuronal damage and minimize the impairment of spatial learning and memory in PTZ kindled rats. Finally, PTZ kindling increases the expression of NLRP1 inflammasome complexes and the levels of inflammatory cytokines IL-1ß, IL-18, IL-6, and TNF-α, which are all attenuated by SN in a dose- dependent manner. CONCLUSIONS: SN exerts anticonvulsant and neuroprotective activity in PTZ kindling model of epilepsy. Disrupting the kindling acquisition, which inhibits NLRP1 inflammasome-mediated inflammatory process, might be involved in its effects.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Excitação Neurológica/efeitos dos fármacos , Morfinanos/uso terapêutico , Proteínas do Tecido Nervoso/metabolismo , Análise de Variância , Animais , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 1/genética , Caspase 1/metabolismo , Convulsivantes/toxicidade , Citocinas/metabolismo , Modelos Animais de Doenças , Epilepsia/induzido quimicamente , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , Pentilenotetrazol/toxicidade , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
13.
Connect Tissue Res ; 59(6): 581-592, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29649906

RESUMO

BACKGROUND: Acute lung injury (ALI) is a type of severe pulmonary inflammatory disease with high rates of morbidity and mortality. Now, an increasing number of studies suggest that lncRNAs may act as key regulators of the inflammatory response and play a crucial role in the pathogenesis of many inflammatory diseases. Our study firstly explored the function and underlying mechanism of lncRNA metastasis-associated lung adenocarcinoma transcription 1 (MALAT1) in regulating the inflammatory response of lipopolysaccharide (LPS)-induced ALI in rats. METHODS: The ALI rats were constructed by intratracheal instillation with LPS. Hematoxylin and eosin (HE) for histological examination were performed to detect histopathological changes in the lung tissues. Enzyme-linked immunosorbent assay (ELISA) was used to determine the concentrations of cytokines TNF-α, IL-6, and IL-1ß in the supernatants of the bronchoalveolar lavage fluid (BALF). Quantitative real-time PCR (qRT-PCR) analysis was employed to assess the expression of MALAT1, miR-146a, TNF-α, IL-6, and IL-1ß in lung tissues. Luciferase reporter assay and RNA immunoprecipitation (RIP) assay were used to detect the relationship between MALAT1 and miR-146a. RESULTS: The results revealed that MALAT1 knockdown played a protective role in the LPS-induced ALI rat model. In addition, knockdown of MALAT1 in vitro inhibited LPS-induced inflammatory response in murine alveolar macrophages cell line MH-S and murine alveolar epithelial cell line MLE-12. This study found that MALAT1 acts as a molecular sponge for miR-146a and MALAT1 negatively regulated miR-146a expression. Mechanistically, MALAT1 overexpression alleviated the inhibitory effect of miR-146a on LPS-induced inflammatory response in MH-S. CONCLUSIONS: Together, our study provided the first evidence that MALAT1 knockdown could suppress inflammatory response by up-regulating miR-146a in LPS-induced ALI, which provided a potential therapeutic target for the treatment of ALI.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Lipopolissacarídeos/toxicidade , MicroRNAs/biossíntese , RNA Longo não Codificante/metabolismo , Regulação para Cima/efeitos dos fármacos , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Animais , Técnicas de Silenciamento de Genes , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , MicroRNAs/genética , RNA Longo não Codificante/genética , Ratos , Ratos Sprague-Dawley
14.
J Environ Sci (China) ; 42: 32-40, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27090692

RESUMO

Size-classified daily aerosol mass concentrations and concentrations of water-soluble inorganic ions were measured in Hefei, China, in four representative months between September 2012 and August 2013. An annual average mass concentration of 169.09 µg/m(3) for total suspended particulate (TSP) was measured using an Andersen Mark-II cascade impactor. The seasonal average mass concentration was highest in winter (234.73 µg/m(3)) and lowest in summer (91.71 µg/m(3)). Water-soluble ions accounted for 59.49%, 32.90%, 48.62% and 37.08% of the aerosol mass concentration in winter, spring, summer, and fall, respectively, which indicated that ionic species were the primary constituents of the atmospheric aerosols. The four most abundant ions were NO3(-), SO4(2-), Ca(2+) and NH4(+). With the exception of Ca(2+), the mass concentrations of water-soluble ions were in an intermediate range compared with the levels for other Chinese cities. Sulfate, nitrate, and ammonium were the dominant fine-particle species, which were bimodally distributed in spring, summer and fall; however, the size distribution became unimodal in winter, with a peak at 1.1-2.1 µm. The Ca(2+) peak occurred at approximately 4.7-5.8 µm in all seasons. The cation to anion ratio was close to 1.4, which suggested that the aerosol particles were alkalescent in Hefei. The average NO3(-)/SO4(2-) mass ratio was 1.10 in Hefei, which indicated that mobile source emissions were predominant. Significant positive correlation coefficients between the concentrations of NH4(+) and SO4(2-), NH4(+) and NO3(-), SO4(2-) and NO3(-), and Mg(2+) and Ca(2+) were also indicated, suggesting that aerosol particles may be present as (NH4)2SO4, NH4HSO4, and NH4NO3.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Aerossóis/química , Poluentes Atmosféricos/química , Atmosfera , China , Nitratos/análise , Material Particulado , Solubilidade , Sulfatos/análise , Água
15.
J Neurosci ; 34(10): 3493-508, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24599450

RESUMO

Many studies have reported a withdrawal-dependent increase in synaptic AMPA receptor (AMPAR) levels in the nucleus accumbens (NAc) of cocaine-sensitized rats; however, the exact relationship between the expression of sensitization and altered AMPAR surface expression in the NAc has not yet been investigated. We demonstrated that the expression of behavioral sensitization was negatively controlled by N-ethylmaleimide-sensitive factor (NSF)-GluR2 interactions in the NAc. The upregulation of NSF-GluR2 interactions, which may be resulted by the increase in NSF S-nitrosylation after withdrawal from cocaine, was associated with the changes in the expression of behavioral sensitization. Disruption of NSF-GluR2 interactions in the NAc with a specific peptide, TAT-pep-R845A, increased the locomotor response of rats to cocaine by decreasing GluR2 surface insertion. In contrast, prevention of GluR2-containing AMPARs removal from synapses with Pep2-EVKI attenuated the expression of behavioral sensitization. Similarly, treatment with the nitric oxide donor, S-Nitroso-N-acetyl-DL-penicillamine (SNAP), attenuated the expression of locomotor sensitization by promoting GluR2 surface expression. This effect was mediated by the binding of S-nitrosylated NSF to GluR2, which promoted the surface expression of AMPARs. Noticeably, exogenous injection of SNAP into NAc also attenuated the expression of cocaine-induced conditioned place preference. Thus, these results indicate that increased NSF-GluR2 interactions in the NAc after withdrawal from cocaine attenuated the expression of behavioral sensitization and serves as a negative regulatory mechanism in drug-exposed individuals.


Assuntos
Cocaína/administração & dosagem , Atividade Motora/fisiologia , Proteínas Sensíveis a N-Etilmaleimida/biossíntese , Núcleo Accumbens/metabolismo , Receptores de AMPA/biossíntese , Sequência de Aminoácidos , Animais , Masculino , Microinjeções/métodos , Dados de Sequência Molecular , Atividade Motora/efeitos dos fármacos , Proteínas Sensíveis a N-Etilmaleimida/genética , Núcleo Accumbens/efeitos dos fármacos , Ligação Proteica/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/genética , Síndrome de Abstinência a Substâncias/metabolismo
16.
J Neurochem ; 132(1): 124-34, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25279828

RESUMO

As an endogenous gaseous molecule, hydrogen sulfide (H2 S) has attracted extensive attention because of its multiple biological effects. However, the effect of H2 S on amygdala-mediated emotional memory has not been elucidated. Here, by employing Pavlovian fear conditioning, an animal model widely used to explore the neural substrates of emotion, we determined whether H2 S could regulate emotional memory. It was shown that the H2 S levels in the amygdala of rats were significantly elevated after cued fear conditioning. Both intraamygdala and systemic administrations of H2 S markedly enhanced amygdala-dependent cued fear memory in rats. Moreover, it was found that H2 S selectively increased the surface expression and currents of NMDA-type glutamate receptor subunit 2B (GluN2B)-containing NMDA receptors (NMDARs) in lateral amygdala of rats, whereas blockade of GluN2B-containing NMDARs in lateral amygdala eliminated the effects of H2 S to enhance amygdalar long-term potentiation and cued fear memory. These results demonstrate that H2 S can regulate amygdala-dependent emotional memory by promoting the function of GluN2B-containing NMDARs in amygdala, suggesting that H2 S-associated signaling may hold potential as a new target for the treatment of emotional disorders. In our study, the effect of hydrogen sulfide (H2 S) on amygdala-mediated emotional memory was investigated. It was found that H2 S could enhance amygdala-dependent emotional memory and long-term potentiation (LTP) in rats by selectively increasing the function of GluN2B-containing NMDA receptors in the amygdala. These results suggest that H2 S-associated signaling may be a new target for the treatment of emotional disorders.


Assuntos
Tonsila do Cerebelo/efeitos dos fármacos , Emoções/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , Memória/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Animais , Condicionamento Psicológico/efeitos dos fármacos , Sinais (Psicologia) , Medo/fisiologia , Sulfeto de Hidrogênio/administração & dosagem , Masculino , Atividade Motora/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
17.
ScientificWorldJournal ; 2014: 807693, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25121138

RESUMO

Because solder joint interconnections are the weaknesses of microelectronic packaging, their reliability has great influence on the reliability of the entire packaging structure. Based on an accelerated life test the reliability assessment and life prediction of lead-free solder joints using Weibull distribution are investigated. The type-I interval censored lifetime data were collected from a thermal cycling test, which was implemented on microelectronic packaging with lead-free ball grid array (BGA) and fine-pitch ball grid array (FBGA) interconnection structures. The number of cycles to failure of lead-free solder joints is predicted by using a modified Engelmaier fatigue life model and a type-I censored data processing method. Then, the Pan model is employed to calculate the acceleration factor of this test. A comparison of life predictions between the proposed method and the ones calculated directly by Matlab and Minitab is conducted to demonstrate the practicability and effectiveness of the proposed method. At last, failure analysis and microstructure evolution of lead-free solders are carried out to provide useful guidance for the regular maintenance, replacement of substructure, and subsequent processing of electronic products.


Assuntos
Cobre/química , Eletrônica , Modelos Químicos , Prata/química , Compostos de Estanho/química , Análise de Falha de Equipamento , Temperatura Alta , Teste de Materiais , Microscopia Eletrônica de Varredura
18.
Sci Data ; 11(1): 425, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658632

RESUMO

Near-surface atmospheric moisture is a key environmental and hydro-climatic variable that has significant implications for the natural and human systems. However, high-resolution moisture data are severely lacking for fine-scale studies. Here, we develop the first 1 km high spatial resolution dataset of monthly moisture index collection in China (HiMIC-Monthly) over a long period of 2003~2020. HiMIC-Monthly is generated by the light gradient boosting machine algorithm (LightGBM) based on observations at 2,419 weather stations and multiple covariates, including land surface temperature, vapor pressure, land cover, impervious surface proportion, population density, and topography. This collection includes six commonly used moisture indices, enabling fine-scale assessment of moisture conditions from different perspectives. Results show that the HiMIC-Monthly dataset has a good performance, with R2 values for all six moisture indices exceeding 0.96 and root mean square error and mean absolute error values within a reasonable range. The dataset exhibits high consistency with in situ observations over various spatial and temporal regimes, demonstrating broad applicability and strong reliability.

19.
Schizophr Res ; 264: 282-289, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38198881

RESUMO

BACKGROUND: Numerous studies have implicated abnormal insulin-like growth factor 1 (IGF-1) in the pathophysiology of schizophrenia, but findings have been inconsistent. METHODS: We conducted a meta-analysis to compare IGF-1 levels in schizophrenia patients with healthy controls and explored factors contributing to variability between estimates. In an independent sample (58 chronic schizophrenia patients and 30 healthy controls), we investigated differences in IGF-1 levels among schizophrenia subgroups with distinct cognitive profiles, identified using k-means clustering based on five cognitive domains from The Repeatable Battery for the Assessment of Neuropsychological Status. Associations between serum IGF-1 levels and clinical and neurocognitive improvements were also examined. RESULTS: The meta-analysis revealed significantly lower serum IGF-1 levels in schizophrenia patients compared to healthy controls, albeit with high heterogeneity. Medication status, BMI, and severity of negative symptoms were identified as potential contributors to this heterogeneity. In our independent study, antipsychotic treatment led to a significant increase in IGF-1 levels, and lower pre-treatment serum IGF-1 levels correlated with greater improvement in cognitive deficits, particularly in a subgroup with more severe cognitive symptoms. CONCLUSIONS: Our findings support the "IGF-1 deficiency hypothesis" in the pathogenesis of schizophrenia. Further research is crucial to elucidate the role of IGF-1 in the cognitive impairments associated with schizophrenia.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Esquizofrenia , Humanos , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/uso terapêutico , Peptídeos Semelhantes à Insulina , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico , Esquizofrenia/diagnóstico
20.
Sci Adv ; 10(13): eadl1598, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552023

RESUMO

Heatwaves are consecutive hot days with devastating impacts on human health and the environment. These events may evolve across both space and time, characterizing a spatiotemporally contiguous propagation pattern that has not been fully understood. Here, we track the spatiotemporally contiguous heatwaves in both reanalysis datasets and model simulations and examine their moving patterns (i.e., moving distance, speed, and direction) in different continents and periods. Substantial changes in contiguous heatwaves have been identified from 1979 to 2020, with longer persistence, longer traveling distance, and slower propagation. These changes have been amplified since 1997, probably due to the weakening of eddy kinetic energy, zonal wind, and anthropogenic forcing. The results suggest that longer-lived, longer-traveling, and slower-moving contiguous heatwaves will cause more devastating impacts on human health and the environment in the future if greenhouse gas emissions keep rising and no effective measures are taken immediately. Our findings provide important implications for the adaption and mitigation of globally connected extreme heatwaves.

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