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1.
Cell ; 176(5): 998-1013.e16, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30712876

RESUMO

Lung cancer is closely associated with chronic inflammation, but the causes of inflammation and the specific immune mediators have not been fully elucidated. The lung is a mucosal tissue colonized by a diverse bacterial community, and pulmonary infections commonly present in lung cancer patients are linked to clinical outcomes. Here, we provide evidence that local microbiota provoke inflammation associated with lung adenocarcinoma by activating lung-resident γδ T cells. Germ-free or antibiotic-treated mice were significantly protected from lung cancer development induced by Kras mutation and p53 loss. Mechanistically, commensal bacteria stimulated Myd88-dependent IL-1ß and IL-23 production from myeloid cells, inducing proliferation and activation of Vγ6+Vδ1+ γδ T cells that produced IL-17 and other effector molecules to promote inflammation and tumor cell proliferation. Our findings clearly link local microbiota-immune crosstalk to lung tumor development and thereby define key cellular and molecular mediators that may serve as effective targets in lung cancer intervention.


Assuntos
Interações entre Hospedeiro e Microrganismos/imunologia , Linfócitos Intraepiteliais/imunologia , Neoplasias Pulmonares/imunologia , Animais , Proliferação de Células , Feminino , Interleucina-17/imunologia , Interleucina-1beta/metabolismo , Interleucina-23/metabolismo , Linfócitos Intraepiteliais/metabolismo , Linfócitos Intraepiteliais/fisiologia , Pulmão/imunologia , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microbiota/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Neutrófilos/imunologia , Receptores de Antígenos de Linfócitos T gama-delta , Simbiose/imunologia , Linfócitos T/imunologia
2.
Nature ; 629(8014): 1091-1099, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38750363

RESUMO

The baobab trees (genus Adansonia) have attracted tremendous attention because of their striking shape and distinctive relationships with fauna1. These spectacular trees have also influenced human culture, inspiring innumerable arts, folklore and traditions. Here we sequenced genomes of all eight extant baobab species and argue that Madagascar should be considered the centre of origin for the extant lineages, a key issue in their evolutionary history2,3. Integrated genomic and ecological analyses revealed the reticulate evolution of baobabs, which eventually led to the species diversity seen today. Past population dynamics of Malagasy baobabs may have been influenced by both interspecific competition and the geological history of the island, especially changes in local sea levels. We propose that further attention should be paid to the conservation status of Malagasy baobabs, especially of Adansonia suarezensis and Adansonia grandidieri, and that intensive monitoring of populations of Adansonia za is required, given its propensity for negatively impacting the critically endangered Adansonia perrieri.


Assuntos
Adansonia , Filogenia , Adansonia/classificação , Adansonia/genética , Biodiversidade , Conservação dos Recursos Naturais , Ecologia , Espécies em Perigo de Extinção , Evolução Molecular , Genoma de Planta/genética , Madagáscar , Dinâmica Populacional , Elevação do Nível do Mar
3.
Nature ; 621(7977): 75-81, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37673990

RESUMO

Benefiting from high energy density (2,600 Wh kg-1) and low cost, lithium-sulfur (Li-S) batteries are considered promising candidates for advanced energy-storage systems1-4. Despite tremendous efforts in suppressing the long-standing shuttle effect of lithium polysulfides5-7, understanding of the interfacial reactions of lithium polysulfides at the nanoscale remains elusive. This is mainly because of the limitations of in situ characterization tools in tracing the liquid-solid conversion of unstable lithium polysulfides at high temporal-spatial resolution8-10. There is an urgent need to understand the coupled phenomena inside Li-S batteries, specifically, the dynamic distribution, aggregation, deposition and dissolution of lithium polysulfides. Here, by using in situ liquid-cell electrochemical transmission electron microscopy, we directly visualized the transformation of lithium polysulfides over electrode surfaces at the atomic scale. Notably, an unexpected gathering-induced collective charge transfer of lithium polysulfides was captured on the nanocluster active-centre-immobilized surface. It further induced an instantaneous deposition of nonequilibrium Li2S nanocrystals from the dense liquid phase of lithium polysulfides. Without mediation of active centres, the reactions followed a classical single-molecule pathway, lithium polysulfides transforming into Li2S2 and Li2S step by step. Molecular dynamics simulations indicated that the long-range electrostatic interaction between active centres and lithium polysulfides promoted the formation of a dense phase consisting of Li+ and Sn2- (2 < n ≤ 6), and the collective charge transfer in the dense phase was further verified by ab initio molecular dynamics simulations. The collective interfacial reaction pathway unveils a new transformation mechanism and deepens the fundamental understanding of Li-S batteries.

4.
Trends Biochem Sci ; 49(6): 475-476, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38538407

RESUMO

Lipid nanodiscs are popular mimetics of biological membranes for determining membrane protein structures. However, a recent study revealed that the choice of nanodisc scaffold directly influenced the structure of an ion channel. This finding prompts us to be cautious and calls for improved membrane mimetics for structure determination.


Assuntos
Proteínas de Membrana , Nanoestruturas , Bicamadas Lipídicas/química , Lipídeos/química , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Nanoestruturas/química , Conformação Proteica
5.
Immunity ; 51(3): 522-534.e7, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31471107

RESUMO

Although recent progress provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), rare anti-PF therapeutics show definitive promise for treating this disease. Repeated lung epithelial injury results in injury-repairing response and inflammation, which drive the development of PF. Here, we report that chronic lung injury inactivated the ubiquitin-editing enzyme A20, causing progressive accumulation of the transcription factor C/EBPß in alveolar macrophages (AMs) from PF patients and mice, which upregulated a number of immunosuppressive and profibrotic factors promoting PF development. In response to chronic lung injury, elevated glycogen synthase kinase-3ß (GSK-3ß) interacted with and phosphorylated A20 to suppress C/EBPß degradation. Ectopic expression of A20 or pharmacological restoration of A20 activity by disturbing the A20-GSK-3ß interaction accelerated C/EBPß degradation and showed potent therapeutic efficacy against experimental PF. Our study indicates that a regulatory mechanism of the GSK-3ß-A20-C/EBPß axis in AMs may be a potential target for treating PF and fibroproliferative lung diseases.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Macrófagos/metabolismo , Fibrose Pulmonar/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina/metabolismo , Animais , Linhagem Celular , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HEK293 , Humanos , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/fisiologia , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia , Regulação para Cima/fisiologia
6.
Proc Natl Acad Sci U S A ; 120(18): e2302325120, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37098056

RESUMO

Integral membrane protein structure determination traditionally requires extraction from cell membranes using detergents or polymers. Here, we describe the isolation and structure determination of proteins in membrane vesicles derived directly from cells. Structures of the ion channel Slo1 from total cell membranes and from cell plasma membranes were determined at 3.8 Å and 2.7 Å resolution, respectively. The plasma membrane environment stabilizes Slo1, revealing an alteration of global helical packing, polar lipid, and cholesterol interactions that stabilize previously unresolved regions of the channel and an additional ion binding site in the Ca2+ regulatory domain. The two methods presented enable structural analysis of both internal and plasma membrane proteins without disrupting weakly interacting proteins, lipids, and cofactors that are essential to biological function.


Assuntos
Canais Iônicos , Proteínas de Membrana , Proteínas de Membrana/metabolismo , Membrana Celular/metabolismo , Canais Iônicos/metabolismo , Sítios de Ligação
7.
J Virol ; 98(3): e0194423, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38421166

RESUMO

Since the first human infection reported in 2013, H7N9 avian influenza virus (AIV) has been regarded as a serious threat to human health. In this study, we sought to identify the virulence determinant of the H7N9 virus in mammalian hosts. By comparing the virulence of the SH/4664 H7N9 virus, a non-virulent H9N2 virus, and various H7N9-H9N2 hybrid viruses in infected mice, we first pinpointed PB2 as the primary viral factor accounting for the difference between H7N9 and H9N2 in mammalian virulence. We further analyzed the in vivo effects of individually mutating H7N9 PB2 residues different from the closely related H9N2 virus and consequently found residue 473, alongside the well-known residue 627, to be critical for the virulence of the H7N9 virus in mice and the activity of its reconstituted viral polymerase in mammalian cells. The importance of PB2-473 was further strengthened by studying reverse H7N9 substitutions in the H9N2 background. Finally, we surprisingly found that species-specific usage of ANP32A, a family member of host factors connecting with the PB2-627 polymorphism, mediates the contribution of PB2 473 residue to the mammalian adaption of AIV polymerase, as the attenuating effect of PB2 M473T on the viral polymerase activity and viral growth of the H7N9 virus could be efficiently complemented by co-expression of chicken ANP32A but not mouse ANP32A and ANP32B. Together, our studies uncovered the PB2 473 residue as a novel viral host range determinant of AIVs via species-specific co-opting of the ANP32 host factor to support viral polymerase activity.IMPORTANCEThe H7N9 avian influenza virus has been considered to have the potential to cause the next pandemic since the first case of human infection reported in 2013. In this study, we identified PB2 residue 473 as a new determinant of mouse virulence and mammalian adaptation of the viral polymerase of the H7N9 virus and its non-pathogenic H9N2 counterparts. We further demonstrated that the variation in PB2-473 is functionally linked to differential co-opting of the host ANP32A protein in supporting viral polymerase activity, which is analogous to the well-known PB2-627 polymorphism, albeit the two PB2 positions are spatially distant. By providing new mechanistic insight into the PB2-mediated host range determination of influenza A viruses, our study implicated the potential existence of multiple PB2-ANP32 interfaces that could be targets for developing new antivirals against the H7N9 virus as well as other mammalian-adapted influenza viruses.


Assuntos
Subtipo H7N9 do Vírus da Influenza A , Influenza Humana , Proteínas Nucleares , Proteínas de Ligação a RNA , Animais , Humanos , Camundongos , Subtipo H7N9 do Vírus da Influenza A/metabolismo , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Vírus da Influenza A Subtipo H9N2 , Influenza Humana/virologia , Mamíferos , Proteínas Nucleares/metabolismo , Nucleotidiltransferases/metabolismo , Proteínas de Ligação a RNA/metabolismo , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo , Virulência , Replicação Viral
8.
Arterioscler Thromb Vasc Biol ; 44(7): 1617-1627, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38721707

RESUMO

BACKGROUND: While it has been hypothesized that high plaque stress and strain may be related to plaque rupture, its direct verification using in vivo coronary plaque rupture data and full 3-dimensional fluid-structure interaction models is lacking in the current literature due to difficulty in obtaining in vivo plaque rupture imaging data from patients with acute coronary syndrome. This case-control study aims to use high-resolution optical coherence tomography-verified in vivo plaque rupture data and 3-dimensional fluid-structure interaction models to seek direct evidence for the high plaque stress/strain hypothesis. METHODS: In vivo coronary plaque optical coherence tomography data (5 ruptured plaques, 5 no-rupture plaques) were acquired from patients using a protocol approved by the local institutional review board with informed consent obtained. The ruptured caps were reconstructed to their prerupture morphology using neighboring plaque cap and vessel geometries. Optical coherence tomography-based 3-dimensional fluid-structure interaction models were constructed to obtain plaque stress, strain, and flow shear stress data for comparative analysis. The rank-sum test in the nonparametric test was used for statistical analysis. RESULTS: Our results showed that the average maximum cap stress and strain values of ruptured plaques were 142% (457.70 versus 189.22 kPa; P=0.0278) and 48% (0.2267 versus 0.1527 kPa; P=0.0476) higher than that for no-rupture plaques, respectively. The mean values of maximum flow shear stresses for ruptured and no-rupture plaques were 145.02 dyn/cm2 and 81.92 dyn/cm2 (P=0.1111), respectively. However, the flow shear stress difference was not statistically significant. CONCLUSIONS: This preliminary case-control study showed that the ruptured plaque group had higher mean maximum stress and strain values. Due to our small study size, larger scale studies are needed to further validate our findings.


Assuntos
Doença da Artéria Coronariana , Vasos Coronários , Placa Aterosclerótica , Estresse Mecânico , Tomografia de Coerência Óptica , Humanos , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/fisiopatologia , Vasos Coronários/patologia , Ruptura Espontânea , Estudos de Casos e Controles , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Idoso , Valor Preditivo dos Testes , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/fisiopatologia , Síndrome Coronariana Aguda/etiologia
9.
J Immunol ; 211(9): 1367-1375, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37695685

RESUMO

A better understanding of the regulatory mechanisms governing the development of memory CD8+ T cells could provide instructive insights into vaccination strategies and T cell-based immunotherapies. In this article, we showed that CD160 surface protein is required for CD8+ T cell memory formation. In the response to acute lymphocytic choriomeningitis virus infection in a mouse model, CD160 ablation resulted in the failure of the development of all three memory CD8+ T cell subsets (central, effective, and tissue-resident memory), concomitant with a skewed differentiation into short-lived effector T cells. Such memory-related defect was manifested by a diminished protection from viral rechallenge. Mechanistically, CD160 deficiency led to downregulation of 4-1BB in activated CD8+ T cells, which contributes to the impaired cell survival and decreased respiratory capacity. The nexus between CD160 and 4-1BB was substantiated by the observation that ectopic introduction of 4-1BB was able to largely complement the loss of CD160 in memory CD8+ T cell development. Collectively, our studies discovered that CD160, once thought to be a coinhibitor of T cell signaling, is an essential promoter of memory CD8+ T cell development via activation of the costimulatory molecule 4-1BB.

10.
Proc Natl Acad Sci U S A ; 119(27): e2115939119, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35763578

RESUMO

Positive magnetoresistance (PMR) and negative magnetoresistance (NMR) describe two opposite responses of resistance induced by a magnetic field. Materials with giant PMR are usually distinct from those with giant NMR due to different physical natures. Here, we report the unusual photomagnetoresistance in the van der Waals heterojunctions of WSe2/quasi-two-dimensional electron gas, showing the coexistence of giant PMR and giant NMR. The PMR and NMR reach 1,007.5% at -9 T and -93.5% at 2.2 T in a single device, respectively. The magnetoresistance spans over two orders of magnitude on inversion of field direction, implying a giant unidirectional magnetoresistance (UMR). By adjusting the thickness of the WSe2 layer, we achieve the maxima of PMR and NMR, which are 4,900,000% and -99.8%, respectively. The unique magnetooptical transport shows the unity of giant UMR, PMR, and NMR, referred to as giant bipolar unidirectional photomagnetoresistance. These features originate from strong out-of-plane spin splitting, magnetic field-enhanced recombination of photocarriers, and the Zeeman effect through our experimental and theoretical investigations. This work offers directions for high-performance light-tunable spintronic devices.NMR).

11.
Chem Soc Rev ; 53(10): 5264-5290, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38619389

RESUMO

The energy storage and vehicle industries are heavily investing in advancing all-solid-state batteries to overcome critical limitations in existing liquid electrolyte-based lithium-ion batteries, specifically focusing on mitigating fire hazards and improving energy density. All-solid-state lithium-sulfur batteries (ASSLSBs), featuring earth-abundant sulfur cathodes, high-capacity metallic lithium anodes, and non-flammable solid electrolytes, hold significant promise. Despite these appealing advantages, persistent challenges like sluggish sulfur redox kinetics, lithium metal failure, solid electrolyte degradation, and manufacturing complexities hinder their practical use. To facilitate the transition of these technologies to an industrial scale, bridging the gap between fundamental scientific research and applied R&D activities is crucial. Our review will address the inherent challenges in cell chemistries within ASSLSBs, explore advanced characterization techniques, and delve into innovative cell structure designs. Furthermore, we will provide an overview of the recent trends in R&D and investment activities from both academia and industry. Building on the fundamental understandings and significant progress that has been made thus far, our objective is to motivate the battery community to advance ASSLSBs in a practical direction and propel the industrialized process.

12.
J Cell Mol Med ; 28(14): e18543, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39054575

RESUMO

The significance of iron in myocardial mitochondria function cannot be underestimated, because deviations in iron levels within cardiomyocytes may have profound detrimental effects on cardiac function. In this study, we investigated the effects of ferroportin 1 (FPN1) on cardiac iron levels and pathological alterations in mice subjected to chronic intermittent hypoxia (CIH). The cTNT-FPN1 plasmid was administered via tail vein injection to induce the mouse with FPN1 overexpression in the cardiomyocytes. CIH was established by exposing the mice to cycles of 21%-5% FiO2 for 3 min, 8 h per day. Subsequently, the introduction of hepcidin resulted in a reduction in FPN1 expression, and H9C2 cells were used to establish an IH model to further elucidate the role of FPN1. First, FPN1 overexpression ameliorated CIH-induced cardiac dysfunction, myocardial hypertrophy, mitochondrial damage and apoptosis. Second, FPN1 overexpression attenuated ROS levels during CIH. In addition, FPN1 overexpression mitigated CIH-induced cardiac iron accumulation. Moreover, the administration of hepcidin resulted in a reduction in FPN1 levels, further accelerating the CIH-induced levels of ROS, LIP and apoptosis in H9C2 cells. These findings indicate that the overexpression of FPN1 in cardiomyocytes inhibits CIH-induced cardiac iron accumulation, subsequently reducing ROS levels and mitigating mitochondrial damage. Conversely, the administration of hepcidin suppressed FPN1 expression and worsened cardiomyocyte iron toxicity injury.


Assuntos
Apoptose , Cardiomegalia , Proteínas de Transporte de Cátions , Hipóxia , Ferro , Miócitos Cardíacos , Espécies Reativas de Oxigênio , Animais , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Cardiomegalia/metabolismo , Cardiomegalia/genética , Cardiomegalia/patologia , Cardiomegalia/etiologia , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genética , Hipóxia/metabolismo , Hipóxia/complicações , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Ferro/metabolismo , Masculino , Hepcidinas/metabolismo , Hepcidinas/genética , Linhagem Celular , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Ratos
13.
J Biol Chem ; 299(6): 104689, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37044216

RESUMO

The basal chordate amphioxus is a model for tracing the origin and evolution of vertebrate immunity. To explore the evolution of immunoreceptor signaling pathways, we searched the associated receptors of the amphioxus Branchiostoma belcheri (Bb) homolog of immunoreceptor signaling adaptor protein Grb2. Mass-spectrum analysis of BbGrb2 immunoprecipitates from B. belcheri intestine lysates revealed a folate receptor (FR) domain- and leucine-rich repeat (LRR)-containing protein (FrLRR). Sequence and structural analysis showed that FrLRR is a membrane protein with a predicted curved solenoid structure. The N-terminal Fr domain contains very few folate-binding sites; the following LRR region is a Slit2-type LRR, and a GPI-anchored site was predicted at the C-terminus. RT-PCR analysis showed FrLRR is a transcription-mediated fusion gene of BbFR-like and BbSlit2-N-like genes. Genomic DNA structure analysis implied the B. belcheri FrLRR gene locus and the corresponding locus in Branchiostoma floridae might be generated by exon shuffling of a Slit2-N-like gene into an FR gene. RT-qPCR, immunostaining, and immunoblot results showed that FrLRR was primarily distributed in B. belcheri intestinal tissue. We further demonstrated that FrLRR localized to the cell membrane and lysosomes. Functionally, FrLRR mediated and promoted bacteria-binding and phagocytosis, and FrLRR antibody blocking or Grb2 knockdown inhibited FrLRR-mediated phagocytosis. Interestingly, we found that human Slit2-N (hSlit2-N) also mediated direct bacteria-binding and phagocytosis which was inhibited by Slit2-N antibody blocking or Grb2 knockdown. Together, these results indicate FrLRR and hSlit2-N may function as phagocytotic-receptors to promote phagocytosis through Grb2, implying the Slit2-N-type-LRR-containing proteins play a role in bacterial binding and elimination.


Assuntos
Anfioxos , Animais , Humanos , Anfioxos/genética , Leucina , Sítios de Ligação , Transdução de Sinais , Fagocitose , Filogenia
14.
J Am Chem Soc ; 146(28): 18899-18904, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38975975

RESUMO

In recent years, dysprosium macrocycle single-molecule magnets (SMMs) have received increasing attention due to their excellent air/thermal stability, strong magnetic anisotropy, and rigid molecular skeleton. However, they usually display fast zero-field quantum tunneling of the magnetization (QTM) rate, severely hindering their data storage applications. Herein, we report the design, synthesis, and characterization of an air-stable monodecker didysprosium macrocycle integrating strong single-ion anisotropy, near-perfect local crystal field (CF) symmetry, and efficient exchange bias. These indispensable features enable clear-cut elucidation of the crucial role of very weak antiferromagnetic coupling on magnetization dynamics, creating a prominent SMM with a large effective energy barrier (Ueff) of 670 cm-1, open hysteresis loops at zero field up to 14.9 K, and a record relaxation time of QTM (τQTM), 24281 s, for all known nonradical-bridged lanthanide SMMs.

15.
J Am Chem Soc ; 146(20): 14058-14066, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38733559

RESUMO

Metal-organic framework (MOF) membranes with high ion selectivity are highly desirable for direct lithium-ion (Li+) separation from industrial brines. However, very few MOF membranes can efficiently separate Li+ from brines of high Mg2+/Li+ concentration ratios and keep stable in ultrahigh Mg2+-concentrated brines. This work reports a type of MOF-channel membranes (MOFCMs) by growing UiO-66-(SH)2 into the nanochannels of polymer substrates to improve the efficiency of MOF membranes for challenging Li+ extraction. The resulting membranes demonstrate excellent monovalent metal ion selectivity over divalent metal ions, with Li+/Mg2+ selectivity up to 103 since Mg2+ should overcome a higher energy barrier than Li+ when transported through the MOF pores, as confirmed by molecular dynamics simulations. Under dual-ion diffusion, as the Mg2+/Li+ mole ratio of the feed solution increases from 0.2 to 30, the membrane Li+/Mg2+ selectivity decreases from 1516 to 19, corresponding to the purity of lithium products between 99.9 and 95.0%. Further research on multi-ion diffusion that involves Mg2+ and three monovalent metal ions (K+, Na+, and Li+, referred to as M+) in the feed solutions shows a significant improvement in Li+/Mg2+ separation efficiency. The Li+/Mg2+ selectivity can go up to 1114 when the Mg2+/M+ molar concentration ratio is 1:1, and it remains at 19 when the ratio is 30:1. The membrane selectivity is also stable for 30 days in a highly concentrated solution with a high Mg2+/Li+ concentration ratio. These results indicate the feasibility of the MOFCMs for direct lithium extraction from brines with Mg2+ concentrations up to 3.5 M. This study provides an alternative strategy for designing efficient MOF membranes in extracting valuable minerals in the future.

16.
J Am Chem Soc ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39108025

RESUMO

Enantiopure Si-stereogenic organosilanes are highly valued in the fields of organic synthesis, development of advanced materials, and drug discovery. However, they are not naturally occurring, and their synthesis has been largely confined to resolution of racemic silanes or desymmetrization of symmetric silanes. In contrast, the dynamic kinetic asymmetric transformation (DYKAT) of racemic organosilanes offers a mechanistically distinct approach and would broaden the accessibility of Si-stereogenic silanes in an enantioconvergent manner. In this study, we report a Lewis base-catalyzed DYKAT of racemic chlorosilanes. The chiral isothiourea catalyst, (S)-benzotetramisole, facilitates silyletherification with phenols, yielding (R)-silylethers in good yields with high enantioselectivity (27 examples, up to 86% yield, up to 98:2 er). Kinetic analysis, control experiments, and DFT calculations suggest that a two-catalyst-bound pentacoordinate silicate is responsible for the Si-configurational epimerization of the ion-paired tetracoordinated silicon intermediates.

17.
Hum Mol Genet ; 31(11): 1733-1746, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34888668

RESUMO

A highly evolutionarily conserved myeloid ecotropic viral integration site 1 (MEIS1) intronic region is strongly associated with restless legs syndrome (RLS) and insomnia. To understand its regulatory function, we dissected the region by analyzing chromatin accessibility, enhancer-promoter contacts, DNA methylation and expression quantitative trait locus (eQTLs) in different human neural cell types and tissues. We observed specific activity with respect to cell type and developmental maturation, indicating a prominent role for distinct highly conserved intronic elements in forebrain inhibitory neuron differentiation. Two elements were hypomethylated in neural cells with higher MEIS1 expression, suggesting a role of enhancer demethylation in gene regulation. MEIS1 eQTLs showed a striking modular chromosomal distribution, with forebrain eQTLs clustering in intron 8/9. Clustered regularly interspersed short palindromic repeats interference targeting of individual elements in this region attenuated MEIS1 expression, revealing a complex regulatory interplay of distinct elements. In summary, we found that MEIS1 regulation is organized in a modular pattern. Disease-associated intronic regulatory elements control MEIS1 expression with cell type and maturation stage specificity, particularly in the inhibitory neuron lineage. The precise spatiotemporal activity of these elements likely contributes to the pathogenesis of insomnia and RLS.


Assuntos
Proteína Meis1 , Síndrome das Pernas Inquietas , Distúrbios do Início e da Manutenção do Sono , Epigênese Genética , Humanos , Íntrons/genética , Proteína Meis1/genética , Síndrome das Pernas Inquietas/genética , Distúrbios do Início e da Manutenção do Sono/genética
18.
J Clin Immunol ; 44(3): 80, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462559

RESUMO

OBJECTIVE: We sought to explore the prevalence of type I interferon-neutralizing antibodies in a Chinese cohort and its clinical implications during the Omicron variant wave of SARS-CoV-2. METHODS: Type I interferon (IFN) autoantibodies possessing neutralizing capabilities were identified using luciferase assays. The capacity of the autoantibodies for in vitro interference with antiviral activity of IFN was assessed by using a SARS-CoV-2 replicon system. An analysis of the demographic and clinical profiles of patients exhibiting neutralizing antibodies was also conducted. RESULTS: In this cohort, 11.8% of severe/critical cases exhibited the existence of type I IFN-neutralizing antibodies, specifically targeting IFN-α2, IFN-ω, or both, with an elderly male patient tendency. Notably, these antibodies exerted a pronounced inhibitory effect on the antiviral activity of IFN against SARS-CoV-2 under controlled in vitro conditions. Furthermore, a noteworthy correlation was discerned between the presence of these neutralizing antibodies and critical clinical parameters, including C-reactive protein (CRP) levels, D-dimer levels, and lymphocyte counts. CONCLUSION: The presence of type I IFN-neutralizing antibodies is a pervasive risk factor for severe/critical COVID-19 in the Chinese population.


Assuntos
COVID-19 , Interferon Tipo I , Idoso , Humanos , Masculino , Autoanticorpos , COVID-19/epidemiologia , SARS-CoV-2 , Prevalência , China/epidemiologia , Anticorpos Neutralizantes , Antivirais
19.
Anal Chem ; 96(19): 7516-7523, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38691765

RESUMO

Herein, single-atom iron doped carbon dots (SA Fe-CDs) were successfully prepared as novel electrochemiluminescence (ECL) emitters with high ECL efficiency, and a biosensor was constructed to ultrasensitively detect microRNA-222 (miRNA-222). Importantly, compared with the conventional without single-atom doped CDs with low ECL efficiency, SA Fe-CDs exhibited strong ECL efficiency, in which single-atom iron as an advanced coreactant accelerator could significantly enhance the generation of reactive oxygen species (ROS) from the coreactant S2O82- for improving the ECL efficiency. Moreover, a neoteric amplification strategy combining the improved strand displacement amplification with Nt.BbvCI enzyme-induced target amplification (ISDA-EITA) could produce 4 output DNAs in every cycle, which greatly improved the amplification efficiency. Thus, a useful ECL biosensor was built with a detection limit of 16.60 aM in the range of 100 aM to 1 nM for detecting traces of miRNA-222. In addition, miRNA-222 in cancer cell lysate (MHCC-97L) was successfully detected by using the ECL biosensor. Therefore, this strategy provides highly efficient single-atom doped ECL emitters for the construction of sensitive ECL biosensing platforms in the biological field and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Carbono , Técnicas Eletroquímicas , Ferro , Medições Luminescentes , MicroRNAs , Pontos Quânticos , MicroRNAs/análise , Carbono/química , Ferro/química , Técnicas Eletroquímicas/métodos , Pontos Quânticos/química , Humanos , Técnicas Biossensoriais/métodos , Limite de Detecção
20.
Genome Res ; 31(5): 890-899, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33875481

RESUMO

Single nucleotide variants (SNVs) within polyadenylation signals (PASs), a specific six-nucleotide sequence required for mRNA maturation, can impair RNA-level gene expression and cause human diseases. However, there is a lack of genome-wide investigation and systematic confirmation tools for identifying PAS variants. Here, we present a computational strategy to integrate the most reliable resources for discovering distinct genomic features of PAS variants and also develop a credible and convenient experimental tool to validate the effect of PAS variants on expression of disease-associated genes. This approach will greatly accelerate the deciphering of PAS variation-related human diseases.


Assuntos
Poliadenilação , RNA Mensageiro , RNA , Sequência de Bases , Doença/genética , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Genômica/métodos , Humanos , Polimorfismo de Nucleotídeo Único , RNA/genética , RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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