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1.
EMBO J ; 42(22): e113383, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37807845

RESUMO

Notch signaling pathway activity, particularly fluctuations in the biologically active effector fragment NICD, is required for rapid and efficient dynamic regulation of proper fate decisions in stem cells. In this study, we identified NEDD4-binding protein 1 (N4BP1), which is highly expressed in the developing mouse cerebral cortex, as a negative modulator of Notch signaling dynamics in neural progenitor cells. Intriguingly, N4BP1 regulated NICD stability specifically after Notch1 S3 cleavage through ubiquitin-mediated degradation that depended on its RAM domain, not its PEST domain, as had been extensively and previously described. The CoCUN domain in N4BP1, particularly the "Phe-Pro" motif (862/863 amino acid), was indispensable for mediating NICD degradation. The Ring family E3 ligase Trim21 was, in contrast to other NEDD4 family members, required for N4BP1-regulated NICD degradation. Overexpression of N4BP1 in cortical neural progenitors promoted neural stem cell differentiation, whereas neural progenitor cells lacking N4BP1 were sensitized to Notch signaling, resulting in the maintenance of stem-like properties in neural progenitor cells and lower production of cortical neurons.


Assuntos
Neocórtex , Células-Tronco Neurais , Animais , Camundongos , Diferenciação Celular/fisiologia , Neocórtex/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Receptor Notch1/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais/fisiologia
2.
Phys Chem Chem Phys ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946575

RESUMO

Supported noble metal nanocatalysts typically exhibit strong crystal plane dependent catalytic behavior, but their working mechanism is still unclear. Herein, using anatase TiO2 with well-exposed crystal facets of {101}, {100} and {001} as a prototype support, Pd- and Pt-based supported TiO2 nanocatalysts (TiO2-Pd and TiO2-Pt) were prepared by chemical reduction with NaBH4 as reducer, and they showed a distinct metal-dependent crystal facet effect in the selective hydrogenation of cinamaldehyde (CAL). For Pd-based nanocatalysts, most Pd species on the {100} plane of TiO2 are present in the oxidized form with positive charges and unexpectedly show higher reactivity than the Pd species in the zero-valence state on the {101} and {001} planes. On the contrary, Pt species on all three crystal planes of TiO2 show zero-valence state, with relatively low conversion, but much better selectivity for hydrogenation of a CO bond than Pd-based catalysts. Well-designed experiments manipulating the stability and type of surface oxygen species confirmed that the essence of the crystal facet effect of the catalyst support actually creates a unique nanoconfined interface at the molecular level to construct a surface p-band intermediate state (PBIS), which provides a new alternative channel for surface electron transfer and consequently accelerates the reaction kinetics.

3.
Langmuir ; 39(10): 3610-3618, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36862534

RESUMO

Although mesoporous silica nanoparticles (MSNs) have been intensively investigated, their mesostructure and formation mechanism are still a topic of debate. Here, we show that MSNS are generated at the interface of the biphasic water-surfactant-triethanolamine-tetraalkoxysilane (TAOS) quaternary system. The spontaneous microemulsification of the hydrophobic TAOS generates microdroplets and direct micelles that both determine the particle size and the pore size. We confirmed also that the dendritic morphology with conical pores is an intermediate species, which readily transforms into regular MSNs concomitantly with the collapse of the microemulsion due to the continuous consumption of TAOS. The prominent effect of the microemulsion on the mechanism growth as a primary template is thoroughly investigated and named here tetraalkoxysilane-assisted self-emulsification templating.

4.
Cereb Cortex ; 32(8): 1668-1681, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-34550336

RESUMO

Emx1IRES-Cre, D6-Cre and hGFAP-Cre are commonly used to conditionally manipulate gene expression or lineage tracing because of their specificity in the dorsal telencephalon during early neurogenesis as previously described. However, the spatiotemporal differences in Cre recombinase activity would lead to divergent phenotypes. Here, we compared the patterns of Cre activity in the early embryos among the three lines by mating with reporter mice. The activities of Emx1IRES-Cre, D6-Cre and hGFAP-Cre were observed in the dorsal telencephalon, starting from approximately embryonic day 9.5, 11.5 and 12.5, respectively. Although all the three lines have activity in radial glial cells, Emx1IRES-Cre fully covers the dorsal and medial telencephalon, including the archicortex and cortical hem. D6-Cre is highly restricted to the dorsal telencephalon with anterior-low to posterior-high gradients, partially covers the hippocampus, and absent in the cortical hem. Moreover, both Emx1IRES-Cre and hGFAP-Cre exhibit Cre activity outside the dorsal neocortex. Meanwhile, we used the three Cre lines to mediate Dicer knockout and observed inconsistent phenotypes, including discrepancies in radial glial cell number, survival and neurogenesis in the neocortex and hippocampus. Together we proved differences in Cre activity can perturb the resultant phenotypes, which aid researchers in appropriate experimental design.


Assuntos
Neocórtex , Animais , Hipocampo/metabolismo , Integrases/genética , Integrases/metabolismo , Camundongos , Camundongos Transgênicos , Neocórtex/metabolismo , Neurogênese
5.
J Chem Phys ; 159(23)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38099550

RESUMO

Aggregation-induced emission (AIE) is an effective strategy for improving the photoluminescence (PL) performance of metal nanoclusters (MNCs). However, the origin of AIE in MNCs is still not fully understood, which is pivotal for the design of AIE luminogens (AIEgens). Here, water soluble silver nanoclusters (Ag NCs) with AIE properties were synthesized. These as-synthesized non-luminescent Ag NCs will become photoluminescent when transferred from water to ethanol, and the emission peak was redshifted from ∼560 to ∼600 nm and largely intensified with the addition of Cu2+. The addition of Cu2+ makes a big difference in the PL properties of Ag NCs. That is, the PL will be enhanced if Cu2+ is added with the sequence "Ag NCs + Cu2++EtOH." In contrast, the PL will be quenched if Cu2+ is added with the sequence "Ag NCs + EtOH + Cu2+." The PL was from the supramolecular clusters formed by the assembly of capping ligands on the confined surface of individual silver clusters through weak interactions. The addition of Cu2+ could regulate the assembly structure and further affect the energy lever (p-band) through space electron interactions. These results provide new insights into the AIE process in metal nanoclusters.

6.
Sci Technol Adv Mater ; 24(1): 2210723, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37205011

RESUMO

In the past several decades, noble metal nanoclusters (NMNCs) have been developed as an emerging class of luminescent materials due to their superior photo-stability and biocompatibility, but their luminous quantum yield is relatively low and the physical origin of the bright photoluminescence (PL) of NMNCs remain elusive, which limited their practical application. As the well-defined structure and composition of NMNCs have been determined, in this mini-review, the effect of each component (metal core, ligand shell and interfacial water) on their PL properties and corresponded working mechanism were comprehensively introduced, and a model that structural water molecules dominated p band intermediate state was proposed to give a unified understanding on the PL mechanism of NMNCs and a further perspective to the future developments of NMNCs by revisiting the development of our studies on the PL mechanism of NMNCs in the past decade.

7.
Macromol Rapid Commun ; 43(5): e2100720, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34962323

RESUMO

Nontraditional intrinsic luminescence (NTIL) which always accompanied with aggregation-induced emission (AIE) features has received considerable attention due to their importance in the understanding of basic luminescence principle and potential practical applications. However, the rational modulation of the NTIL of nonconventional luminophores remains difficult, on account of the limited understanding of emission mechanisms. Herein, the emission color of nonconjugated poly(methyl vinyl ether-alt-maleic anhydride) (PMVEMA) can be readily regulated from blue to red by controlling the alkalinity during the hydrolysis process. The nontraditional photoluminescence with AIE property is from the new formed p-band state, resulting from the strong overlapping of p orbitals of the clustered O atoms through space interactions. Hydrated hydroxide complexes embedded in the entangled polymer chain make big difference on the clustering of O atoms which dominates the AIE property of nonconjugated PMVEMA. These new insights into the photoluminescence mechanism of NTIL should stimulate additional experimental and theoretical studies and can benefit the molecular-level design of nontraditional chromophores for optoelectronics and other applications.


Assuntos
Luminescência , Polímeros , Hidróxidos , Anidridos Maleicos
8.
Phys Chem Chem Phys ; 24(13): 7923-7936, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35311880

RESUMO

Generally, the catalytic transformation of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) at heterogeneous metal surfaces follows a Langmuir-Hinshelwood (L-H) mechanism when sodium borohydride (NaBH4) is used as the sacrificial reductant. Herein, with Pt-Ag bimetallic nanoparticles confined in dendritic mesoporous silica nanospheres (DMSNs) as a model catalyst, we demonstrated that the conversion of 4-NP did not pass through the direct hydrogen transfer route with the hydride equivalents being supplied by borohydride via the bimolecular L-H mechanism, since Fourier transform infrared (FTIR) spectroscopy with the use of isotopically labeled reactants (NaBD4 and D2O) showed that the final product of 4-AP was composed of protons (or deuterons) that originated from the solvent water (or heavy water). Combined characterization by X-ray photoelectron spectroscopy (XPS), 1H nuclear magnetic resonance (NMR) and the optical excitation and photoluminescence spectrum evidenced that the surface hydrous hydroxide complex bound to the metal surface (also called structural water molecules, SWs), due to the space overlap of p orbitals of two O atoms in SWs, could form an ensemble of dynamic interface transient states, which provided the alternative electron and proton transfer channels for selective transformation of 4-NP. The cationic Pt species in the Ag-Pt bimetallic catalyst mainly acts as a dynamic adsorption center to temporally anchor SWs and related reactants, and not as the active site for hydrogen activation.


Assuntos
Elétrons , Prótons , Nitrofenóis/química , Água
9.
Cereb Cortex ; 31(9): 4078-4091, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-33822906

RESUMO

Wnt/ß-catenin signaling plays multiple important roles during mammalian brain development, and it regulates the proliferation and differentiation of neural progenitors in a context-dependent manner and affects neocortex layer formation. However, the specific role of Wnt/ß-catenin in neuronal layer fate determination in the neocortex is still unclear. Here, we report that Zbed3, which is a positive regulator of Wnt/ß-catenin signaling, colocalizes with ß-catenin at the endfeet of radial glia in the ventricular zone of embryo mouse neocortex. Overexpression and knockdown of Zbed3 increased and decreased the activity of Wnt/ß-catenin signaling in the neocortex, respectively. Interestingly, knockdown of Zbed3 in vivo could significantly shift neuronal fates from deep layers to upper layers but is not required for the proliferation and differentiation of neural progenitors. Overexpression of Zbed3 led to increased generation of deep-layer neurons without impairing cell cycle exit of neural progenitors. More importantly, knockdown of Zbed3 could effectively block the effects of the ectopic expression of stabilized ß-catenin on neocortex layer formation. Hence, our results demonstrate that Zbed3 is indispensable for Wnt/ß-catenin signaling regulating neuronal layer fates in the developing brain.


Assuntos
Encéfalo/crescimento & desenvolvimento , Córtex Cerebral/crescimento & desenvolvimento , Neocórtex/crescimento & desenvolvimento , Fatores de Transcrição/genética , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/fisiologia , Animais , Diferenciação Celular , Proliferação de Células , Desenvolvimento Embrionário , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Camundongos , Células-Tronco Neurais , Neuroglia , Neurônios , Gravidez , Fatores de Transcrição/biossíntese
10.
Phys Chem Chem Phys ; 23(23): 12950-12957, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34086019

RESUMO

Concerted electron and proton transfer is a key step for the reversible conversion of molecular hydrogen in both heterogeneous nanocatalysis and metalloenzyme catalysis. However, its activation mechanism involving electron and proton transfer kinetics remains elusive. With the most widely used catalytic hydride reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) as a model reaction, we evaluate the catalytic activity of noble metal nanoparticles (NPs) trapped in porous silica in aqueous NaBH4 solution. By virtue of a novel combination of catalyst design, reaction kinetics, isotope labeling, and multiple spectroscopic techniques, the real catalytic site for the conversion of -NO2 to -NH2 is identified to be the water-hydroxyl transition metal complex, which could further react with NaBH4 to form a new triangular configuration metal complex of H3B-water-hydroxyl with dynamic features. It yields an ensemble of surface electronic states (SESs) though space overlapping of p orbitals of one B and several O atoms (including the O atoms of 4-NP), which could act as an alternative channel for concerted electron and proton transfer. This work highlights the critical role of the conceptual SESs model in heterogeneous catalysis to tune the chemical reactivity and also sheds light on the intricate working of the [FeFe]-hydrogenases.

11.
Neurol Sci ; 42(12): 5289-5296, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33860397

RESUMO

BACKGROUND: Determining the rupture risk of unruptured intracranial aneurysm is crucial for treatment strategy. The purpose of this study was to predict the rupture risk of middle cerebral artery (MCA) aneurysms using a machine learning technique. METHODS: We retrospectively reviewed 403 MCA aneurysms and randomly partitioned them into the training and testing datasets with a ratio of 8:2. A generalized linear model with logit link was developed using training dataset to predict the aneurysm rupture risk based on the clinical variables and morphological features manually measured from computed tomography angiography. To facilitate the clinical application, we further constructed an easy-to-use nomogram based on the developed model. RESULTS: Ruptured MCA aneurysm had larger aneurysm size, aneurysm height, perpendicular height, aspect ratio, size ratio, bottleneck factor, and height-width ratio. Presence of a daughter-sac was more common in ruptured than in unruptured MCA aneurysms. Six features, including aneurysm multiplicity, lobulations, size ratio, bottleneck factor, height-width ratio, and aneurysm angle, were adopted in the model after feature selection. The model achieved a relatively good performance with areas under the receiver operating characteristic curves of 0.77 in the training dataset and 0.76 in the testing dataset. The nomogram provided a visual interpretation of our model, and the rupture risk probability of MCA aneurysms can be directly read from it. CONCLUSION: Our model can be used to predict the rupture risk of MCA aneurysm.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/epidemiologia , Angiografia Cerebral , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/epidemiologia , Artéria Cerebral Média/diagnóstico por imagem , Nomogramas , Estudos Retrospectivos , Fatores de Risco
12.
Sensors (Basel) ; 21(5)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804316

RESUMO

Accurate rainfall observation data with high temporal and spatial resolution are essential for national disaster prevention and mitigation as well as climate response decisions. This paper introduces a field experiment using an E-band millimeter-wave link to obtain rainfall rate information in Nanjing city, which is situated in the east of China. The link is 3 km long and operates at 71 and 81 GHz. We first distinguish between the wet and the dry periods, and then determine the classification threshold for calculating attenuation baseline in real time. We correct the influence of the wet antenna attenuation and finally calculate the rainfall rate through the power law relationship between the rainfall rate and the rain-induced attenuation. The experimental results show that the correlation between the rainfall rate retrieved from the 71 GHz link and the rainfall rate measured by the raindrop spectrometer is up to 0.9. The correlation at 81 GHz is up to 0.91. The mean relative errors are all below 5%. By comparing with the rainfall rate measured by the laser raindrop spectrometer set up at the experimental site, we verified the reliability and accuracy of monitoring rainfall using the E-band millimeter-wave link.

13.
Small ; 16(30): e2001989, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32521092

RESUMO

Fluorinated solid-electrolyte interphase (SEI) derived from fluoroethylene carbonate (FEC) is particularly favored for dendrite suppression in lithium metal batteries because of the high Young's modulus (≈64.9 Gpa) and low electronic conductivity (10-31 S cm-1 ) of LiF. However, the transportation ability of Li+ in this fluorinated SEI under high current densities is limited by the low ionic conductivity of LiF (≈10-12 S cm-1 ). Herein, by rational design, 0.1 m lithium bisoxalatodifluorophosphate (LiDFBOP) is adopted to modify fluorinated SEI in FEC based electrolyte for fast charging lithium metal batteries. Benefiting from the synergetic effect of LiDFBOP and FEC, a fluorinated SEI rich in LiF and Lix POy Fz species can be yielded, which can further improve the stability and ionic conductivity of SEI for fast Li+ transportation. Meanwhile, the average coulombic efficiency for Li plating/stripping is improved from 92.0% to 96.7%, thus promoting stable cycling of Li||Li symmetrical batteries with dendrite free morphologies, even at high current densities (3.0 mA cm-2 ) and high plating/stripping capacities (3.0 mAh cm-2 ). More attractively, in practical Li||LiNi0.6 Co0.2 Mn0.2 O2 batteries, the cycling life at 1C and rate capacities at 6C are also significantly improved. Therefore, the synergetic effect of LiDFBOP and FEC provides great potential for achieving advanced lithium metal batteries with fast charging ability.

14.
Acta Biochim Biophys Sin (Shanghai) ; 52(12): 1382-1393, 2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33167028

RESUMO

Dibutyl phthalate (DBP), a kind of typical environmental pollutant, is widely used as plasticizers, and its neurotoxicity and developmental toxicity have been found in recent years. However, whether oral DBP exposure will affect the homeostasis of gut microbiota and its adverse response in liver of mammalians remain unclear. In the present study, 10-week experimental cycles of vehicle or DBP (0.1 and 1 mg/kg) were given to 6-week-old C57BL/6J mice by oral gavage. Our results revealed that the body weight of mice was increased after exposure to both low and high doses of DBP. The serum levels of hepatic triglyceride and total cholesterol were significantly increased in response to both doses of DBP. In addition, some pivotal genes related to lipogenesis were also increased in liver at the mRNA level. Evaluation of gut microbiota by 16S rRNA sequencing technology showed that 0.1 mg/kg DBP exposure significantly affected gut microbiota at the phylum and genus levels. Moreover, DBP exposure decreased mucus secretion and caused inflammation in the gut, leading to the impairment of intestinal barrier function. Exposure to DBP inhibited the expression of peroxisome proliferator-activated receptor-γ and activated the expression of nuclear factor kappa B. In addition, DBP exposure increased the level of lipopolysaccharide in serum, and increased the expression of toll-like receptor 4 and the levels of inflammatory cytokines, such as interleukin (IL)-1ß, IL-6, and tumor necrosis factor alpha, in the liver. These results indicated that exposure to DBP disturbed the homeostasis of gut microbiota, induced hepatic lipid metabolism disorder, and caused liver inflammation in mice via the related gut-liver axis signaling pathways.


Assuntos
Dibutilftalato/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Peso Corporal , Colo/metabolismo , Colo/patologia , Citocinas/metabolismo , Inflamação/induzido quimicamente , Lipídeos/sangue , Lipopolissacarídeos/sangue , Fígado/metabolismo , Fígado/patologia , Camundongos Endogâmicos C57BL , Subunidade p50 de NF-kappa B/metabolismo , RNA Ribossômico 16S , Receptor 4 Toll-Like/metabolismo
15.
Small ; 15(14): e1805420, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30848553

RESUMO

1T phase MoS2 possesses higher conductivity than the 2H phase, which is a key parameter of electrochemical performance for lithium ion batteries (LIBs). Herein, a 1T-MoS2 /C hybrid is successfully synthesized through facile hydrothermal method with a proper glucose additive. The synthesized hybrid material is composed of smaller and fewer-layer 1T-MoS2 nanosheets covered by thin carbon layers with an enlarged interlayer spacing of 0.94 nm. When it is used as an anode material for LIBs, the enlarged interlayer spacing facilitates rapid intercalating and deintercalating of lithium ions and accommodates volume change during cycling. The high intrinsic conductivity of 1T-MoS2 also contributes to a faster transfer of lithium ions and electrons. Moreover, much smaller and fewer-layer nanosheets can shorten the diffusion path of lithium ions and accelerate reaction kinetics, leading to an improved electrochemical performance. It delivers a high initial capacity of 920.6 mAh g-1 at 1 A g-1 and the capacity can maintain 870 mAh g-1 even after 300 cycles, showing a superior cycling stability. The electrode presents a high rate performance as well with a reversible capacity of 600 mAh g-1 at 10 A g-1 . These results show that the 1T-MoS2 /C hybrid shows potential for use in high-performance lithium-ion batteries.

16.
Biomed Eng Online ; 18(1): 103, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653267

RESUMO

BACKGROUND: Quantitative ultrasound has been used for the assessment of cancellous bone status. The attenuation mechanisms of cancellous bone, however, have not been well understood, because the microstructure of cancellous bone is significantly inhomogeneous and the interaction between ultrasound and the microstructure of cancellous bone is complex. In this study, a theoretical approach was applied to investigate the influence of the microstructure of cancellous bone on ultrasonic attenuation. RESULTS: The scattering from a trabecular cylinder was significantly angle dependent. The dependencies of the ultrasonic attenuation on frequency, scatterer size, and porosity were explored from the theoretical calculation. Prediction results showed that the ultrasonic attenuation increased with the increase of frequency and decreased linearly with the increase in porosity, and the broadband ultrasound attenuation decreased with the increase in porosity. All these predicted trends were consistent with published experimental data. In addition, our model successfully explained the principle of broadband ultrasound attenuation measurement (i.e., the attenuation over the frequency range 0.3-0.65 MHz was approximately linearly proportional to frequency) by considering the contributions of scattering and absorption to attenuation. CONCLUSION: The proposed theoretical model may be a potentially valuable tool for understanding the interaction of ultrasound with cancellous bone.


Assuntos
Osso Esponjoso/citologia , Osso Esponjoso/diagnóstico por imagem , Modelos Biológicos , Processamento de Imagem Assistida por Computador , Ultrassonografia
17.
Acta Biochim Biophys Sin (Shanghai) ; 51(8): 834-844, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31314053

RESUMO

Our previous finding demonstrated that chronic corticosterone (CORT) may be involved in mediating the pathophysiology of premature aging in rats. Frequent jet lag increases the risk for many diseases, including obesity and type 2 diabetes, and is associated with the aging processes. However, the effect of jet lag on CORT-induced depression and its association with aging phenotypes remain unclear. In this study, the rats were exposed to both CORT and jet lag treatment, and the differences were analyzed and compared to rats with single CORT treatment. Our results showed that jet lag treatment aggravated CORT-induced depression-like behavior evidenced by sucrose intake test, forced swimming test, and open field test. Additionally, this treatment aggravated the shortening of telomeres, which possibly resulted in decreased telomerase activity, and downregulated the expression of telomere-binding factor 2 (TRF2) and telomerase reverse transcriptase compared to that in CORT rats, as revealed by quantitative real-time-polymerase chain reaction and western blot analysis, respectively. The shortening of telomeres may have been caused by increased oxidative stress, which was associated with the inhibition of sirtuin 3. Exposure to jet lag also aggravated the degeneration of mitochondrial functions, as shown by the decreases in the mRNA expression of COX1, ND1, and Tfam. Our findings provide physiological evidence that jet lag exposure may worsen stress-induced depression and age-related abnormalities.


Assuntos
Envelhecimento , Corticosterona/efeitos adversos , Depressão/etiologia , Síndrome do Jet Lag , Animais , Comportamento Animal , Corticosterona/administração & dosagem , Ciclo-Oxigenase 1/metabolismo , Depressão/induzido quimicamente , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Proteínas de Membrana/metabolismo , NADH Desidrogenase/metabolismo , Estresse Oxidativo , Fenótipo , Ratos , Ratos Wistar , Sirtuína 3/antagonistas & inibidores , Proteínas Semelhantes à Proteína de Ligação a TATA-Box/metabolismo , Fatores de Transcrição/metabolismo
18.
Chemistry ; 23(64): 16338-16345, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28850752

RESUMO

A series of Ca-doped lithium vanadates Li3-x Cax VO4 (x=0, 0.01, 0.03, and 0.05) are synthesized successfully through a simple sol-gel method. XRD patterns and energy-dispersive X-ray spectroscopy (EDS) mappings reveal that the doped Ca2+ ions enter into the lattice successfully and are distributed uniformly throughout the Li3 VO4 (LVO) grains. XRD spectra and SEM images show that Ca doping can lead to an enlarged lattice and refined Li3 VO4 particles. A small quantity of V ions will transfer from V5+ to V4+ in the Ca-doped samples, as demonstrated by the X-ray photoelectron spectroscopy (XPS) analysis, which leads to an increase of an order of magnitude in the electronic conductivity. Improved rate capability and cycling stability are observed for the Ca-doped samples, and Li2.97 Ca0.03 VO4 exhibits the best electrochemical performance among the studied materials. The initial charge/discharge capacities at 0.1 C increase from 480/645 to 527/702 mA h g-1 as x varies from 0 to 0.03. The charge capacity of Li2.97 Ca0.03 VO4 at 1 C retains 95.3 % of its initial value after 180 cycles, whereas the capacity retention is only 40 % for the pristine sample. Moreover, Li2.97 Ca0.03 VO4 maintains a high discharge capacity of 301.7 mA h g-1 at a high discharge rate (4 C), whereas the corresponding value is only 95.2 mA h g-1 for the pristine LVO sample. The enhanced cycling and rate performances are ascribed to the increased lithium ion diffusivity and electrical conductivity induced by Ca doping.

19.
Chemosphere ; 359: 142035, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38663680

RESUMO

Hexafluoropropylene oxide trimer acid (HFPO-TA) has been found to cause hepatotoxicity, lipotoxicity, and cytotoxicity. However, the effects of HFPO-TA exposure on nervous system toxicity are still unclear. Here, six-week-old male C57BL/6J mice were treated with 2, 20, and 200 µg/L HFPO-TA for six weeks. The untargeted transcriptome analysis was employed to identify differentially expressed mRNAs in the tissue of mouse hippocampi. Then, the levels of neurotransmitters were detected by ELISA analysis in hippocampal and colonic tissues. Real-time quantitative PCR and western blotting analysis were performed to detect the expression of genes associated with modulation of serotonin (5-HT) metabolism and blood-brain barrier. HFPO-TA exposure reduced the mRNA and protein expression of several tight junction protein-coded genes, including Occludin, Claudin-1, and ZO-1, in mice hippocampi, indicating that the blood-brain barrier was disrupted. Moreover, HFPO-TA exposure elevated the expression of neuroinflammatory factors, including TNF-α, IL-6, IL-1ß, TGF-α, and TGF-ß. Analysis of hippocampal transcriptomics suggested that HFPO-TA exposure would impair 5-HT generation and metabolic pathways. In keeping with this prediction, our findings confirmed that the levels of several neurotransmitters, including tryptophan (TRP), 5-HT, 5-HTP, and 5-HIAA, were all impaired by HFPO-TA exposure in the serum, colon, and hippocampus, as was the colonic and hippocampal expression of TRP and 5-HT metabolism-related genes such as SERT, MAO-A, and IDO. These results suggest that HFPO-TA nervous system toxicity in mice may be partly modulated by the brain-gut axis and that HFPO-TA exposure may negatively impact human mental health.


Assuntos
Eixo Encéfalo-Intestino , Hipocampo , Camundongos Endogâmicos C57BL , Serotonina , Animais , Camundongos , Masculino , Serotonina/metabolismo , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Eixo Encéfalo-Intestino/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Fluorocarbonos/toxicidade
20.
Elife ; 122024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38415809

RESUMO

Despite intense research on mice, the transcriptional regulation of neocortical neurogenesis remains limited in humans and non-human primates. Cortical development in rhesus macaque is known to recapitulate multiple facets of cortical development in humans, including the complex composition of neural stem cells and the thicker supragranular layer. To characterize temporal shifts in transcriptomic programming responsible for differentiation from stem cells to neurons, we sampled parietal lobes of rhesus macaque at E40, E50, E70, E80, and E90, spanning the full period of prenatal neurogenesis. Single-cell RNA sequencing produced a transcriptomic atlas of developing parietal lobe in rhesus macaque neocortex. Identification of distinct cell types and neural stem cells emerging in different developmental stages revealed a terminally bifurcating trajectory from stem cells to neurons. Notably, deep-layer neurons appear in the early stages of neurogenesis, while upper-layer neurons appear later. While these different lineages show overlap in their differentiation program, cell fates are determined post-mitotically. Trajectories analysis from ventricular radial glia (vRGs) to outer radial glia (oRGs) revealed dynamic gene expression profiles and identified differential activation of BMP, FGF, and WNT signaling pathways between vRGs and oRGs. These results provide a comprehensive overview of the temporal patterns of gene expression leading to different fates of radial glial progenitors during neocortex layer formation.


Assuntos
Neocórtex , Células-Tronco Neurais , Feminino , Gravidez , Animais , Camundongos , Transcriptoma , Macaca mulatta , Perfilação da Expressão Gênica
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