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1.
Nat Mater ; 23(4): 527-534, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38454027

RESUMO

The liquid-like feature of thermoelectric superionic conductors is a double-edged sword: the long-range migration of ions hinders the phonon transport, but their directional segregation greatly impairs the service stability. We report the synergetic enhancement in figure of merit (ZT) and stability in Cu1.99Se-based superionic conductors enabled by ion confinement effects. Guided by density functional theory and nudged elastic band simulations, we elevated the activation energy to restrict ion migrations through a cation-anion co-doping strategy. We reduced the carrier concentration without sacrificing the low thermal conductivity, obtaining a ZT of ∼3.0 at 1,050 K. Notably, the fabricated device module maintained a high conversion efficiency of up to ∼13.4% for a temperature difference of 518 K without obvious degradation after 120 cycles. Our work could be generalized to develop electrically and thermally robust functional materials with ionic migration characteristics.

2.
Proc Natl Acad Sci U S A ; 119(38): e2206147119, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36095192

RESUMO

The neocortex, the center for higher brain function, first emerged in mammals and has become massively expanded and folded in humans, constituting almost half the volume of the human brain. Primary microcephaly, a developmental disorder in which the brain is smaller than normal at birth, results mainly from there being fewer neurons in the neocortex because of defects in neural progenitor cells (NPCs). Outer radial glia (oRGs), NPCs that are abundant in gyrencephalic species but rare in lissencephalic species, are thought to play key roles in the expansion and folding of the neocortex. However, how oRGs expand, whether they are necessary for neocortical folding, and whether defects in oRGs cause microcephaly remain important questions in the study of brain development, evolution, and disease. Here, we show that oRG expansion in mice, ferrets, and human cerebral organoids requires cyclin-dependent kinase 6 (CDK6), the mutation of which causes primary microcephaly via an unknown mechanism. In a mouse model in which increased Hedgehog signaling expands oRGs and intermediate progenitor cells and induces neocortical folding, CDK6 loss selectively decreased oRGs and abolished neocortical folding. Remarkably, this function of CDK6 in oRG expansion did not require its kinase activity, was not shared by the highly similar CDK4 and CDK2, and was disrupted by the mutation causing microcephaly. Therefore, our results indicate that CDK6 is conserved to promote oRG expansion, that oRGs are necessary for neocortical folding, and that defects in oRG expansion may cause primary microcephaly.


Assuntos
Quinase 6 Dependente de Ciclina , Células Ependimogliais , Microcefalia , Neocórtex , Animais , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Células Ependimogliais/citologia , Células Ependimogliais/enzimologia , Furões , Proteínas Hedgehog/metabolismo , Humanos , Camundongos , Microcefalia/genética , Neocórtex/anormalidades , Neocórtex/enzimologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/enzimologia , Organoides/embriologia
3.
FASEB J ; 37(8): e23048, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37389895

RESUMO

Vascular smooth muscle cells (VSMCs) are considered to be a crucial source of foam cells in atherosclerosis due to their low expression level of cholesterol exporter ATP-binding cassette transporter A1 (ABCA1) intrinsically. While the definite regulatory mechanisms are complicated and have not yet been fully elucidated, we previously reported that Dickkopf-1 (DKK1) mediates endothelial cell (EC) dysfunction, thereby aggravating atherosclerosis. However, the role of smooth muscle cell (SMC) DKK1 in atherosclerosis and foam cell formation remains unknown. In this study, we established SMC-specific DKK1-knockout (DKK1SMKO ) mice by crossbreeding DKK1flox/flox mice with TAGLN-Cre mice. Then, DKK1SMKO mice were crossed with APOE-/- mice to generate DKK1SMKO /APOE-/- mice, which exhibited milder atherosclerotic burden and fewer SMC foam cells. In vitro loss- and gain-of-function studies of DKK1 in primary human aortic smooth muscle cells (HASMCs) have proven that DKK1 prevented oxidized lipid-induced ABCA1 upregulation and cholesterol efflux and promoted SMC foam cell formation. Mechanistically, RNA-sequencing (RNA-seq) analysis of HASMCs as well as chromatin immunoprecipitation (ChIP) experiments showed that DKK1 mediates the binding of transcription factor CCAAT/enhancer-binding protein delta (C/EBPδ) to the promoter of cytochrome P450 epoxygenase 4A11 (CYP4A11) to regulate its expression. In addition, CYP4A11 as well as its metabolite 20-HETE-promoted activation of transcription factor sterol regulatory element-binding protein 2 (SREBP2) mediated the DKK1 regulation of ABCA1 in SMC. Furthermore, HET0016, the antagonist of CYP4A11, has also shown an alleviating effect on atherosclerosis. In conclusion, our results demonstrate that DKK1 promotes SMC foam cell formation during atherosclerosis via a reduction in CYP4A11-20-HETE/SREBP2-mediated ABCA1 expression.


Assuntos
Aterosclerose , Células Espumosas , Humanos , Animais , Camundongos , Músculo Liso Vascular , Sistema Enzimático do Citocromo P-450 , Fatores de Transcrição , Aterosclerose/genética , Apolipoproteínas E/genética , Citocromo P-450 CYP4A , Transportador 1 de Cassete de Ligação de ATP/genética
4.
Langmuir ; 40(9): 4852-4859, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38382061

RESUMO

Transition metal oxides with the merits of high theoretical capacities, natural abundance, low cost, and environmental benignity have been regarded as a promising anodic material for lithium ion batteries (LIBs). However, the severe volume expansion upon cycling and poor conductivity limit their cycling stability and rate capability. To address this issue, NiO embedded and N-doped porous carbon nanorods (NiO@NCNR) and nanotubes (NiO@NCNT) are synthesized by the metal-catalyzed graphitization and nitridization of monocrystalline Ni(II)-triazole coordinated framework and Ni(II)/melamine mixture, respectively, and the following oxidation in air. When applied as an anodic material for LIBs, the NiO@NCNR and NiO@NCNT hybrids exhibit a decent capacity of 895/832 mA h g-1 at 100 mA g-1, high rate capability of 484/467 mA h g-1 at 5.0 A g-1, and good long-term cycling stability of 663/634 mA h g-1 at 600th cycle at 1 A g-1, which are much better than those of NiO@carbon black (CB) control sample (701, 214, and 223 mA h g-1). The remarkable electrochemical properties benefit from the advanced nanoarchitecture of NiO@NCNR and NiO@NCNT, which offers a length-controlled one-dimensional porous carbon nanoarchitecture for effective e-/Li+ transport, affords a flexible carbon skeleton for spatial confinement, and forms abundant nanocavities for stress buffering and structure reinforcement during discharge/charging processes. The rational structural design and synthesis may pave a way for exploring advanced metal oxide based anodic materials for next-generation LIBs.

5.
Crit Care Med ; 51(10): 1318-1327, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37272947

RESUMO

OBJECTIVES: To determine the effectiveness and safety of ciprofol for sedating patients in ICUs who required mechanical ventilation (MV). DESIGN: A multicenter, single-blind, randomized, noninferiority trial. SETTING: Twenty-one centers across China from December 2020 to June 2021. PATIENTS: A total of 135 ICU patients 18 to 80 years old with endotracheal intubation and undergoing MV, who were expected to require sedation for 6-24 hours. INTERVENTIONS: One hundred thirty-five ICU patients were randomly allocated into ciprofol ( n = 90) and propofol ( n = 45) groups in a 2:1 ratio. Ciprofol or propofol were IV infused at loading doses of 0.1 mg/kg or 0.5 mg/kg, respectively, over 4 minutes ± 30 seconds depending on the physical condition of each patient. Ciprofol or propofol were then immediately administered at an initial maintenance dose of 0.3 mg/kg/hr or 1.5 mg/kg/hr, to achieve the target sedation range of Richmond Agitation-Sedation Scale (+1 to -2). Besides, continuous IV remifentanil analgesia was administered (loading dose: 0.5-1 µg/kg, maintenance dose: 0.02-0.15 µg/kg/min). MEASUREMENTS AND MAIN RESULTS: Of the 135 patients enrolled, 129 completed the study. The primary endpoint-sedation success rates of ciprofol and propofol groups were 97.7% versus 97.8% in the full analysis set (FAS) and were both 100% in per-protocol set (PPS). The noninferiority margin was set as 8% and confirmed with a lower limit of two-sided 95% CI for the inter-group difference of -5.98% and -4.32% in the FAS and PPS groups. Patients who received ciprofol had a longer recovery time ( p = 0.003), but there were no differences in the remaining secondary endpoints (all p > 0.05). The occurrence rates of treatment-emergent adverse events (TEAEs) or drug-related TEAEs were not significantly different between the groups (all p > 0.05). CONCLUSIONS: Ciprofol was well tolerated, with a noninferior sedation profile to propofol in Chinese ICU patients undergoing MV for a period of 6-24 hours.


Assuntos
Propofol , Respiração Artificial , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Respiração Artificial/métodos , Método Simples-Cego , Dor/tratamento farmacológico , Unidades de Terapia Intensiva , Hipnóticos e Sedativos/uso terapêutico
6.
Int J Mol Sci ; 24(16)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37629052

RESUMO

Within arterial plaque, HIV infection creates a state of inflammation and immune activation, triggering NLRP3/caspase-1 inflammasome, tissue damage, and monocyte/macrophage infiltration. Previously, we documented that caspase-1 activation in myeloid cells was linked with HIV-associated atherosclerosis in mice and people with HIV. Here, we mechanistically examined the direct effect of caspase-1 on HIV-associated atherosclerosis. Caspase-1-deficient (Casp-1-/-) mice were crossed with HIV-1 transgenic (Tg26+/-) mice with an atherogenic ApoE-deficient (ApoE-/-) background to create global caspase-1-deficient mice (Tg26+/-/ApoE-/-/Casp-1-/-). Caspase-1-sufficient (Tg26+/-/ApoE-/-/Casp-1+/+) mice served as the controls. Next, we created chimeric hematopoietic cell-deficient mice by reconstituting irradiated ApoE-/- mice with bone marrow cells transplanted from Tg26+/-/ApoE-/-/Casp-1-/- (BMT Casp-1-/-) or Tg26+/-/ApoE-/-/Casp-1+/+ (BMT Casp-1+/+) mice. Global caspase-1 knockout in mice suppressed plaque deposition in the thoracic aorta, serum IL-18 levels, and ex vivo foam cell formation. The deficiency of caspase-1 in hematopoietic cells resulted in reduced atherosclerotic plaque burden in the whole aorta and aortic root, which was associated with reduced macrophage infiltration. Transcriptomic analyses of peripheral mononuclear cells and splenocytes indicated that caspase-1 deficiency inhibited caspase-1 pathway-related genes. These results document the critical atherogenic role of caspase-1 in chronic HIV infection and highlight the implication of this pathway and peripheral immune activation in HIV-associated atherosclerosis.


Assuntos
Aterosclerose , Infecções por HIV , HIV-1 , Placa Aterosclerótica , Animais , Camundongos , Apolipoproteínas E/genética , Aterosclerose/genética , Caspase 1/genética , Infecções por HIV/complicações , Infecções por HIV/genética , Placa Aterosclerótica/genética
7.
Phys Rev Lett ; 128(25): 250401, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35802432

RESUMO

First proposed by Mayers and Yao, self-testing provides a certification method to infer the underlying physics of quantum experiments in a black-box scenario. Numerous demonstrations have been reported to self-test various types of entangled states. However, all the multiparticle self-testing experiments reported so far suffer from both detection and locality loopholes. Here, we report the first experimental realization of multiparticle entanglement self-testing closing the locality loophole in a photonic system, and the detection loophole in a superconducting system, respectively. We certify three-party and four-party GHZ states with at least 0.84(1) and 0.86(3) fidelities in a device-independent way. These results can be viewed as a meaningful advance in multiparticle loophole-free self-testing, and also significant progress on the foundations of quantum entanglement certification.

8.
Phys Rev Lett ; 128(4): 040403, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35148136

RESUMO

Standard quantum theory was formulated with complex-valued Schrödinger equations, wave functions, operators, and Hilbert spaces. Previous work attempted to simulate quantum systems using only real numbers by exploiting an enlarged Hilbert space. A fundamental question arises: are the complex numbers really necessary in the standard formalism of quantum theory? To answer this question, a quantum game has been developed to distinguish standard quantum theory from its real-number analog, by revealing a contradiction between a high-fidelity multiqubit quantum experiment and players using only real-number quantum theory. Here, using superconducting qubits, we faithfully realize the quantum game based on deterministic entanglement swapping with a state-of-the-art fidelity of 0.952. Our experimental results violate the real-number bound of 7.66 by 43 standard deviations. Our results disprove the real-number formulation and establish the indispensable role of complex numbers in the standard quantum theory.

9.
Phys Chem Chem Phys ; 24(44): 27114-27120, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36342075

RESUMO

Fe-based oxides are considered as promising anode materials for lithium-ion batteries (LIBs) due to their high theoretical capacities, low cost, natural abundance and environmental friendliness. However, their severe volume expansion upon cycling and poor conductivity limit their cycling stability and rate capability. To address this issue, a hybrid of Fe2O3 nanoparticles encapsulated at the endpoints of nitrogen-doped CNTs (Fe2O3@NCNTs) is designed and prepared using a metal-catalyzed graphitization-nitridization driven tip-growth process and subsequent oxidation in air. When evaluated as an anode material for LIBs, this Fe2O3@NCNT hybrid exhibits a high capacity of 1145 mA h g-1 at 100 mA g-1, excellent rate capability of 907 mA h g-1 at 5.0 A g-1 and remarkable cycling stability of 856 mA h g-1 after 800 cycles at 1 A g-1, which are much superior to those of the Fe2O3/carbon black (CB) control material. The outstanding electrochemical performance benefits from the unique nanoarchitecture of Fe2O3@NCNTs, which provides a porous conductive matrix for effective electron-ion transport, and provides space confining carbon nanocaps as well as stress buffer nanocavities for robust structural stability during the lithiation/delithiation process. The results may pave the way for the rational structural design of high-performance metal oxide-based anode materials for next-generation LIBs.

10.
Am J Respir Cell Mol Biol ; 64(1): 79-88, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32991819

RESUMO

Preclinical mouse models that recapitulate some characteristics of coronavirus disease (COVID-19) will facilitate focused study of pathogenesis and virus-host responses. Human agniotensin-converting enzyme 2 (hACE2) serves as an entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to infect people via binding to envelope spike proteins. Herein we report development and characterization of a rapidly deployable COVID-19 mouse model. C57BL/6J (B6) mice expressing hACE2 in the lung were transduced by oropharyngeal delivery of the recombinant human adenovirus type 5 that expresses hACE2 (Ad5-hACE2). Mice were infected with SARS-CoV-2 at Day 4 after transduction and developed interstitial pneumonia associated with perivascular inflammation, accompanied by significantly higher viral load in lungs at Days 3, 6, and 12 after infection compared with Ad5-empty control group. SARS-CoV-2 was detected in pneumocytes in alveolar septa. Transcriptomic analysis of lungs demonstrated that the infected Ad5-hACE mice had a significant increase in IFN-dependent chemokines Cxcl9 and Cxcl10, and genes associated with effector T-cell populations including Cd3 g, Cd8a, and Gzmb. Pathway analysis showed that several Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were enriched in the data set, including cytokine-cytokine receptor interaction, the chemokine signaling pathway, the NOD-like receptor signaling pathway, the measles pathway, and the IL-17 signaling pathway. This response is correlative to clinical response in lungs of patients with COVID-19. These results demonstrate that expression of hACE2 via adenovirus delivery system sensitized the mouse to SARS-CoV-2 infection and resulted in the development of a mild COVID-19 phenotype, highlighting the immune and inflammatory host responses to SARS-CoV-2 infection. This rapidly deployable COVID-19 mouse model is useful for preclinical and pathogenesis studies of COVID-19.


Assuntos
Células Epiteliais Alveolares/imunologia , COVID-19/imunologia , Expressão Gênica , SARS-CoV-2/imunologia , Transdução de Sinais/imunologia , Adenoviridae/genética , Adenoviridae/metabolismo , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/virologia , Enzima de Conversão de Angiotensina 2/biossíntese , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/imunologia , Animais , COVID-19/genética , COVID-19/metabolismo , COVID-19/patologia , Citocinas/genética , Citocinas/imunologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Transdução de Sinais/genética , Transdução Genética
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