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1.
Cell ; 180(5): 941-955.e20, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-32109412

RESUMEN

The pyroptosis execution protein GSDMD is cleaved by inflammasome-activated caspase-1 and LPS-activated caspase-11/4/5. The cleavage unmasks the pore-forming domain from GSDMD-C-terminal domain. How the caspases recognize GSDMD and its connection with caspase activation are unknown. Here, we show site-specific caspase-4/11 autoprocessing, generating a p10 product, is required and sufficient for cleaving GSDMD and inducing pyroptosis. The p10-form autoprocessed caspase-4/11 binds the GSDMD-C domain with a high affinity. Structural comparison of autoprocessed and unprocessed capase-11 identifies a ß sheet induced by the autoprocessing. In caspase-4/11-GSDMD-C complex crystal structures, the ß sheet organizes a hydrophobic GSDMD-binding interface that is only possible for p10-form caspase-4/11. The binding promotes dimerization-mediated caspase activation, rendering a cleavage independently of the cleavage-site tetrapeptide sequence. Crystal structure of caspase-1-GSDMD-C complex shows a similar GSDMD-recognition mode. Our study reveals an unprecedented substrate-targeting mechanism for caspases. The hydrophobic interface suggests an additional space for developing inhibitors specific for pyroptotic caspases.


Asunto(s)
Inflamasomas/ultraestructura , Complejos Multiproteicos/ultraestructura , Proteínas de Unión a Fosfato/ultraestructura , Piroptosis/genética , Animales , Caspasa 1/química , Caspasa 1/genética , Caspasa 1/ultraestructura , Caspasas Iniciadoras/química , Caspasas Iniciadoras/genética , Cristalografía por Rayos X , Células HEK293 , Células HeLa , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Inflamasomas/genética , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/genética , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Proteínas de Unión a Fosfato/química , Proteínas de Unión a Fosfato/genética , Conformación Proteica en Lámina beta/genética , Dominios Proteicos/genética , Procesamiento Proteico-Postraduccional/genética , Proteolisis
2.
Nature ; 616(7958): 774-782, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37076619

RESUMEN

For unknow reasons, the melanocyte stem cell (McSC) system fails earlier than other adult stem cell populations1, which leads to hair greying in most humans and mice2,3. Current dogma states that McSCs are reserved in an undifferentiated state in the hair follicle niche, physically segregated from differentiated progeny that migrate away following cues of regenerative stimuli4-8. Here we show that most McSCs toggle between transit-amplifying and stem cell states for both self-renewal and generation of mature progeny, a mechanism fundamentally distinct from those of other self-renewing systems. Live imaging and single-cell RNA sequencing revealed that McSCs are mobile, translocating between hair follicle stem cell and transit-amplifying compartments where they reversibly enter distinct differentiation states governed by local microenvironmental cues (for example, WNT). Long-term lineage tracing demonstrated that the McSC system is maintained by reverted McSCs rather than by reserved stem cells inherently exempt from reversible changes. During ageing, there is accumulation of stranded McSCs that do not contribute to the regeneration of melanocyte progeny. These results identify a new model whereby dedifferentiation is integral to homeostatic stem cell maintenance and suggest that modulating McSC mobility may represent a new approach for the prevention of hair greying.


Asunto(s)
Desdiferenciación Celular , Folículo Piloso , Melanocitos , Nicho de Células Madre , Células Madre , Animales , Humanos , Ratones , Folículo Piloso/citología , Melanocitos/citología , Células Madre/citología , Microambiente Celular , Linaje de la Célula , Envejecimiento , Homeostasis , Color del Cabello/fisiología
3.
Mol Cell ; 81(2): 355-369.e10, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33321093

RESUMEN

Ferroptosis is a form of necrotic cell death caused by iron-dependent peroxidation of polyunsaturated phospholipids on cell membranes and is actively suppressed by the cellular antioxidant systems. We report here that oxidoreductases, including NADPH-cytochrome P450 reductase (POR) and NADH-cytochrome b5 reductase (CYB5R1), transfer electrons from NAD(P)H to oxygen to generate hydrogen peroxide, which subsequently reacts with iron to generate reactive hydroxyl radicals for the peroxidation of the polyunsaturated fatty acid (PUFA) chains of membrane phospholipids, thereby disrupting membrane integrity during ferroptosis. Genetic knockout of POR and CYB5R1 decreases cellular hydrogen peroxide generation, preventing lipid peroxidation and ferroptosis. Moreover, POR knockdown in mouse liver prevents ConA-induced liver damage. Ferroptosis, therefore, is a result of incidental electron transfer carried out by POR/CYB5R1 oxidoreductase and thus needs to be constitutively countered by the antioxidant systems.


Asunto(s)
Membrana Celular/química , Sistema Enzimático del Citocromo P-450/genética , Citocromo-B(5) Reductasa/genética , Ácidos Grasos Insaturados/metabolismo , Ferroptosis/genética , NADP/metabolismo , Animales , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Concanavalina A/farmacología , Sistema Enzimático del Citocromo P-450/deficiencia , Citocromo-B(5) Reductasa/deficiencia , Transporte de Electrón/efectos de los fármacos , Ferroptosis/efectos de los fármacos , Células HEK293 , Células HeLa , Humanos , Peróxido de Hidrógeno/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Oxígeno/metabolismo , Compuestos de Fenilurea/farmacología , Piperazinas/farmacología , Piridinas/farmacología , Sorafenib/farmacología
4.
Proc Natl Acad Sci U S A ; 121(8): e2316716121, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38349874

RESUMEN

Understanding the molecular-level mechanisms involved in transmembrane ion selectivity is essential for optimizing membrane separation performance. In this study, we reveal our observations regarding the transmembrane behavior of Li+ and Mg2+ ions as a response to the changing pore solvation abilities of the covalent-organic-framework (COF) membranes. These abilities were manipulated by adjusting the lengths of the oligoether segments attached to the pore channels. Through comparative experiments, we were able to unravel the relationships between pore solvation ability and various ion transport properties, such as partitioning, conduction, and selectivity. We also emphasize the significance of the competition between Li+ and Mg2+ with the solvating segments in modulating selectivity. We found that increasing the length of the oligoether chain facilitated ion transport; however, it was the COF membrane with oligoether chains containing two ethylene oxide units that exhibited the most pronounced discrepancy in transmembrane energy barrier between Li+ and Mg2+, resulting in the highest separation factor among all the evaluated membranes. Remarkably, under electro-driven binary-salt conditions, this specific COF membrane achieved an exceptional Li+/Mg2+ selectivity of up to 1352, making it one of the most effective membranes available for Li+/Mg2+ separation. The insights gained from this study significantly contribute to advancing our understanding of selective ion transport within confined nanospaces and provide valuable design principles for developing highly selective COF membranes.

5.
J Biol Chem ; 300(7): 107425, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823639

RESUMEN

Adenosine deaminase (ADA) catalyzes the irreversible deamination of adenosine (ADO) to inosine and regulates ADO concentration. ADA ubiquitously expresses in various tissues to mediate ADO-receptor signaling. A significant increase in plasma ADA activity has been shown to be associated with the pathogenesis of type 2 diabetes mellitus. Here, we show that elevated plasma ADA activity is a compensated response to high level of ADO in type 2 diabetes mellitus and plays an essential role in the regulation of glucose homeostasis. Supplementing with more ADA, instead of inhibiting ADA, can reduce ADO levels and decrease hepatic gluconeogenesis. ADA restores a euglycemic state and recovers functional islets in db/db and high-fat streptozotocin diabetic mice. Mechanistically, ADA catabolizes ADO and increases Akt and FoxO1 phosphorylation independent of insulin action. ADA lowers blood glucose at a slower rate and longer duration compared to insulin, delaying or blocking the incidence of insulinogenic hypoglycemia shock. Finally, ADA suppresses gluconeogenesis in fasted mice and insulin-deficient diabetic mice, indicating the ADA regulating gluconeogenesis is a universal biological mechanism. Overall, these results suggest that ADA is expected to be a new therapeutic target for diabetes.


Asunto(s)
Adenosina Desaminasa , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Gluconeogénesis , Animales , Masculino , Ratones , Adenosina/metabolismo , Adenosina Desaminasa/metabolismo , Glucemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Insulina/metabolismo , Hígado/metabolismo , Ratones Endogámicos C57BL , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética
6.
J Biol Chem ; : 107783, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39303913

RESUMEN

N6-Methyladenosine (m6A) is the most prevalent mRNA modification. Its biological function primarily relies on its "Reader" protein, such as YTHDC2. Previous studies have shown that YTHDC2 downregulation is a pro-carcinogenic phenomenon in lung adenocarcinoma (LUAD). However, further investigation is needed to understand the molecular mechanisms of downstream genes and the associated biological phenomena following YTHDC2 downregulation. Here, we found that YTHDC2 knockout upregulated exosome content in LUAD. Following YTHDC2 knockout, the mRNA levels of OAS family members (OASs) and IFIT family members (IFITs) also decreased; and inhibition of OASs and IFITs could promote exosome content. Several m6A modification sites on the NT domain of OASs and the TPR12 domain of IFITs were found to increase the stability of OASs and IFITs in a YTHDC2-dependent manner. OASs and IFITs affected exosome content through target genes including RAB5A, RAB7 and RAB11A, and three arginine (R) amino acids on IFITs were critical for combination IFITs with targeted RAB mRNAs and subsequent degradation. Simultaneously, OASs degraded targeted RABs through RNAseL. Additionally, mutual bindings between OASs and IFITs were critical for their target gene degradation. Collectively, the above findings might provide a theoretical basis for the treatment of LUAD patients with low YTHDC2 expression.

7.
N Engl J Med ; 386(3): 252-263, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-34767706

RESUMEN

BACKGROUND: The relation between sodium intake and cardiovascular disease remains controversial, owing in part to inaccurate assessment of sodium intake. Assessing 24-hour urinary excretion over a period of multiple days is considered to be an accurate method. METHODS: We included individual-participant data from six prospective cohorts of generally healthy adults; sodium and potassium excretion was assessed with the use of at least two 24-hour urine samples per participant. The primary outcome was a cardiovascular event (coronary revascularization or fatal or nonfatal myocardial infarction or stroke). We analyzed each cohort using consistent methods and combined the results using a random-effects meta-analysis. RESULTS: Among 10,709 participants, who had a mean (±SD) age of 51.5±12.6 years and of whom 54.2% were women, 571 cardiovascular events were ascertained during a median study follow-up of 8.8 years (incidence rate, 5.9 per 1000 person-years). The median 24-hour urinary sodium excretion was 3270 mg (10th to 90th percentile, 2099 to 4899). Higher sodium excretion, lower potassium excretion, and a higher sodium-to-potassium ratio were all associated with a higher cardiovascular risk in analyses that were controlled for confounding factors (P≤0.005 for all comparisons). In analyses that compared quartile 4 of the urinary biomarker (highest) with quartile 1 (lowest), the hazard ratios were 1.60 (95% confidence interval [CI], 1.19 to 2.14) for sodium excretion, 0.69 (95% CI, 0.51 to 0.91) for potassium excretion, and 1.62 (95% CI, 1.25 to 2.10) for the sodium-to-potassium ratio. Each daily increment of 1000 mg in sodium excretion was associated with an 18% increase in cardiovascular risk (hazard ratio, 1.18; 95% CI, 1.08 to 1.29), and each daily increment of 1000 mg in potassium excretion was associated with an 18% decrease in risk (hazard ratio, 0.82; 95% CI, 0.72 to 0.94). CONCLUSIONS: Higher sodium and lower potassium intakes, as measured in multiple 24-hour urine samples, were associated in a dose-response manner with a higher cardiovascular risk. These findings may support reducing sodium intake and increasing potassium intake from current levels. (Funded by the American Heart Association and the National Institutes of Health.).


Asunto(s)
Enfermedades Cardiovasculares/etiología , Sodio en la Dieta/efectos adversos , Adulto , Anciano , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Potasio/administración & dosificación , Potasio/orina , Estudios Prospectivos , Sodio/orina , Sodio en la Dieta/administración & dosificación
8.
J Virol ; 98(4): e0015924, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38499512

RESUMEN

Equine herpesvirus type 8 (EHV-8) causes abortion and respiratory disease in horses and donkeys, leading to serious economic losses in the global equine industry. Currently, there is no effective vaccine or drug against EHV-8 infection, underscoring the need for a novel antiviral drug to prevent EHV-8-induced latent infection and decrease the pathogenicity of this virus. The present study demonstrated that hyperoside can exert antiviral effects against EHV-8 infection in RK-13 (rabbit kidney cells), MDBK (Madin-Darby bovine kidney), and NBL-6 cells (E. Derm cells). Mechanistic investigations revealed that hyperoside induces heme oxygenase-1 expression by activating the c-Jun N-terminal kinase/nuclear factor erythroid-2-related factor 2/Kelch-like ECH-associated protein 1 axis, alleviating oxidative stress and triggering a downstream antiviral interferon response. Accordingly, hyperoside inhibits EHV-8 infection. Meanwhile, hyperoside can also mitigate EHV-8-induced injury in the lungs of infected mice. These results indicate that hyperoside may serve as a novel antiviral agent against EHV-8 infection.IMPORTANCEHyperoside has been reported to suppress viral infections, including herpesvirus, hepatitis B virus, infectious bronchitis virus, and severe acute respiratory syndrome coronavirus 2 infection. However, its mechanism of action against equine herpesvirus type 8 (EHV-8) is currently unknown. Here, we demonstrated that hyperoside significantly inhibits EHV-8 adsorption and internalization in susceptible cells. This process induces HO-1 expression via c-Jun N-terminal kinase/nuclear factor erythroid-2-related factor 2/Kelch-like ECH-associated protein 1 axis activation, alleviating oxidative stress and triggering an antiviral interferon response. These findings indicate that hyperoside could be very effective as a drug against EHV-8.


Asunto(s)
Antivirales , Infecciones por Herpesviridae , Herpesvirus Équido 1 , Sistema de Señalización de MAP Quinasas , Quercetina , Animales , Bovinos , Ratones , Conejos , Antivirales/farmacología , Caballos , Interferones/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Quercetina/análogos & derivados , Quercetina/farmacología , Línea Celular
9.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38221903

RESUMEN

The advent of single-cell RNA sequencing (scRNA-seq) has revolutionized our understanding of cellular heterogeneity and complexity in biological tissues. However, the nature of large, sparse scRNA-seq datasets and privacy regulations present challenges for efficient cell identification. Federated learning provides a solution, allowing efficient and private data use. Here, we introduce scFed, a unified federated learning framework that allows for benchmarking of four classification algorithms without violating data privacy, including single-cell-specific and general-purpose classifiers. We evaluated scFed using eight publicly available scRNA-seq datasets with diverse sizes, species and technologies, assessing its performance via intra-dataset and inter-dataset experimental setups. We find that scFed performs well on a variety of datasets with competitive accuracy to centralized models. Though Transformer-based model excels in centralized training, its performance slightly lags behind single-cell-specific model within the scFed framework, coupled with a notable time complexity concern. Our study not only helps select suitable cell identification methods but also highlights federated learning's potential for privacy-preserving, collaborative biomedical research.


Asunto(s)
Investigación Biomédica , Análisis de Expresión Génica de una Sola Célula , Aprendizaje , Algoritmos , Benchmarking , Análisis de Secuencia de ARN
10.
Plant Physiol ; 194(3): 1411-1430, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-37879112

RESUMEN

Arabidopsis (Arabidopsis thaliana) ecotype Col-0 has plastid and mitochondrial genomes encoding over 100 proteins. Public databases (e.g. Araport11) have redundancy and discrepancies in gene identifiers for these organelle-encoded proteins. RNA editing results in changes to specific amino acid residues or creation of start and stop codons for many of these proteins, but the impact of RNA editing at the protein level is largely unexplored due to the complexities of detection. Here, we assembled the nonredundant set of identifiers, their correct protein sequences, and 452 predicted nonsynonymous editing sites of which 56 are edited at lower frequency. We then determined accumulation of edited and/or unedited proteoforms by searching ∼259 million raw tandem MS spectra from ProteomeXchange, which is part of PeptideAtlas (www.peptideatlas.org/builds/arabidopsis/). We identified all mitochondrial proteins and all except 3 plastid-encoded proteins (NdhG/Ndh6, PsbM, and Rps16), but no proteins predicted from the 4 ORFs were identified. We suggest that Rps16 and 3 of the ORFs are pseudogenes. Detection frequencies for each edit site and type of edit (e.g. S to L/F) were determined at the protein level, cross-referenced against the metadata (e.g. tissue), and evaluated for technical detection challenges. We detected 167 predicted edit sites at the proteome level. Minor frequency sites were edited at low frequency at the protein level except for cytochrome C biogenesis 382 at residue 124 (Ccb382-124). Major frequency sites (>50% editing of RNA) only accumulated in edited form (>98% to 100% edited) at the protein level, with the exception of Rpl5-22. We conclude that RNA editing for major editing sites is required for stable protein accumulation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteoma/genética , Proteoma/metabolismo , Plastidios/genética , Plastidios/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo
11.
Plant Physiol ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39133898

RESUMEN

The extensive use of nitrogen fertilizer boosts rice (Oryza sativa) production but also harms ecosystems. Therefore, enhancing crop nitrogen use efficiency is crucial. Here, we performed map-based cloning and identified the EARLY FLOWERING3 (ELF3) like protein-encoding gene OsELF3-1, which confers enhanced nitrogen uptake in rice. OsELF3-1 forms a ternary complex (OsEC) with OsELF4s and OsLUX, the putative orthologs of ELF4 and LUX ARRHYTHMO (LUX) in Arabidopsis (Arabidopsis thaliana), respectively. OsEC directly binds to the promoter of Grain number, plant height, and heading date7 (Ghd7) and represses its expression. Ghd7 encodes a transcription factor that has major effects on multiple agronomic traits. Ghd7 is also a transcriptional repressor and directly suppresses the expression of ABC1 REPRESSOR1 (ARE1), a negative regulator of nitrogen use efficiency. Therefore, targeting the OsEC-Ghd7-ARE1 module offers an approach to enhance nitrogen uptake, presenting promising avenues for sustainable agriculture.

12.
Acc Chem Res ; 57(14): 1973-1984, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38950424

RESUMEN

ConspectusMembranes are pivotal in a myriad of energy production processes and modern separation techniques. They are essential in devices for energy generation, facilities for extracting energy elements, and plants for wastewater treatment, each of which hinges on effective ion separation. While biological ion channels show exceptional permeability and selectivity, designing synthetic membranes with defined pore architecture and chemistry on the (sub)nanometer scale has been challenging. Consequently, a typical trade-off emerges: highly permeable membranes often sacrifice selectivity and vice versa. To tackle this dilemma, a comprehensive understanding and modeling of synthetic membranes across various scales is imperative. This lays the foundation for establishing design criteria for advanced membrane materials. Key attributes for such materials encompass appropriately sized pores, a narrow pore size distribution, and finely tuned interactions between desired permeants and the membrane. The advent of covalent-organic-framework (COF) membranes offers promising solutions to the challenges faced by conventional membranes in selective ion separation within the water-energy nexus. COFs are molecular Legos, facilitating the precise integration of small organic structs into extended, porous, crystalline architectures through covalent linkage. This unique molecular architecture allows for precise control over pore sizes, shapes, and distributions within the membrane. Additionally, COFs offer the flexibility to modify their pore spaces with distinct functionalities. This adaptability not only enhances their permeability but also facilitates tailored interactions with specific ions. As a result, COF membranes are positioned as prime candidates to achieve both superior permeability and selectivity in ion separation processes.In this Account, we delineate our endeavors aimed at leveraging the distinctive attributes of COFs to augment ion separation processes, tackling fundamental inquiries while identifying avenues for further exploration. Our strategies for fabricating COF membranes with enhanced ion selectivity encompass the following: (1) crafting (sub)nanoscale ion channels to enhance permselectivity, thereby amplifying energy production; (2) implementing a multivariate (MTV) synthesis method to control charge density within nanochannels, optimizing ion transport efficiency; (3) modifying the pore environment within confined mass transfer channels to establish distinct pathways for ion transport. For each strategy, we expound on its chemical foundations and offer illustrative examples that underscore fundamental principles. Our efforts have culminated in the creation of groundbreaking membrane materials that surpass traditional counterparts, propelling advancements in sustainable energy conversion, waste heat utilization, energy element extraction, and pollutant removal. These innovations are poised to redefine energy systems and industrial wastewater management practices. In conclusion, we outline future research directions and highlight key challenges that need addressing to enhance the ion/molecular recognition capabilities and practical applications of COF membranes. Looking forward, we anticipate ongoing advancements in functionalization and fabrication techniques, leading to enhanced selectivity and permeability, ultimately rivaling the capabilities of biological membranes.

13.
Nano Lett ; 24(7): 2328-2336, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38345437

RESUMEN

Atomic ordering of noble metal alloys is an effective strategy for improving catalytic performance, yet the low-temperature synthesis of ordered alloys still faces significant challenges. The low-temperature liquid phase method has enormous potential for the synthesis of alloys; however, the atomic ordering mechanism of this process has not been thoroughly studied. Herein, we investigate the mechanism of the influence of metal precursors, reducing agents, solvents, and mixing modes of reactant regulating strategies on precious metal alloy ordering using this method. These regulating strategies are designed to change the coordination structure of metal complexes, affect the reduction potential of metals, and thus change the reduction order of metals and their arrangement in the alloy products. Notably, the reduction potential differences between metal complexes can be used to predict the ordering of the synthetic products (Pd-Cu, Pd-Cd, Pd-Sn, Pd-Pb, and Pt-Sn). This work provides an excellent platform for investigating atomic arrangement engineering.

14.
Nano Lett ; 24(3): 975-982, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38189647

RESUMEN

Ferroelectric memristors hold immense promise for advanced memory and neuromorphic computing. However, they face limitations due to low readout current density in conventional designs with low-conductive ferroelectric channels, especially at the nanoscale. Here, we report a ferroelectric-mediated memristor utilizing a 2D MoS2 nanoribbon channel with an ultrascaled cross-sectional area of <1000 nm2, defined by a ferroelectric BaTiO3 nanoribbon stacked on top. Strikingly, the Schottky barrier at the MoS2 contact can be effectively tuned by the charge transfers coupled with quasi-zero-dimensional polarization charges formed at the two ends of the nanoribbon, which results in distinctive resistance switching accompanied by multiple negative differential resistance showing the high-current density of >104 A/cm2. The associated space charges in BaTiO3 are minimized to ∼3.7% of the polarization charges, preserving nonvolatile polarization. This achievement establishes ferroelectric-mediated nanoscale semiconductor memristors with high readout current density as promising candidates for memory and highly energy-efficient in-memory computing applications.

15.
Nano Lett ; 24(26): 8151-8161, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38912914

RESUMEN

The size of liposomal drugs has been demonstrated to strongly correlate with their pharmacokinetics and pharmacodynamics. While the microfluidic method successfully achieves the production of liposomes with well-controlled sizes across various buffer/lipid flow rate ratio (FRR) settings, any adjustments to the FRR inevitably influence the concentration, encapsulation efficiency (EE), and stability of liposomal drugs. Here we describe a controllable cavitation-on-a-chip (CCC) strategy that facilitates the precise regulation of liposomal drug size at any desired FRR. The CCC-enabled size-specific liposomes exhibited striking differences in uptake and biodistribution behaviors, thereby demonstrating distinct antitumor efficacy in both tumor-bearing animal and melanoma patient-derived organoid (PDO) models. Intriguingly, as the liposome size decreased to approximately 80 nm, the preferential accumulation of liposomal drugs in the liver transitioned to a predominant enrichment in the kidneys. These findings underscore the considerable potential of our CCC approach in influencing the pharmacokinetics and pharmacodynamics of liposomal nanomedicines.


Asunto(s)
Dispositivos Laboratorio en un Chip , Liposomas , Liposomas/química , Animales , Humanos , Ratones , Distribución Tisular , Tamaño de la Partícula , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Melanoma/tratamiento farmacológico , Melanoma/patología
16.
J Proteome Res ; 23(9): 3984-4004, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39101213

RESUMEN

This study presents the Maize PeptideAtlas resource (www.peptideatlas.org/builds/maize) to help solve questions about the maize proteome. Publicly available raw tandem mass spectrometry (MS/MS) data for maize collected from ProteomeXchange were reanalyzed through a uniform processing and metadata annotation pipeline. These data are from a wide range of genetic backgrounds and many sample types and experimental conditions. The protein search space included different maize genome annotations for the B73 inbred line from MaizeGDB, UniProtKB, NCBI RefSeq, and for the W22 inbred line. 445 million MS/MS spectra were searched, of which 120 million were matched to 0.37 million distinct peptides. Peptides were matched to 66.2% of proteins in the most recent B73 nuclear genome annotation. Furthermore, most conserved plastid- and mitochondrial-encoded proteins (NCBI RefSeq annotations) were identified. Peptides and proteins identified in the other B73 genome annotations will improve maize genome annotation. We also illustrate the high-confidence detection of unique W22 proteins. N-terminal acetylation, phosphorylation, ubiquitination, and three lysine acylations (K-acetyl, K-malonyl, and K-hydroxyisobutyryl) were identified and can be inspected through a PTM viewer in PeptideAtlas. All matched MS/MS-derived peptide data are linked to spectral, technical, and biological metadata. This new PeptideAtlas is integrated in MaizeGDB with a peptide track in JBrowse.


Asunto(s)
Anotación de Secuencia Molecular , Proteínas de Plantas , Espectrometría de Masas en Tándem , Zea mays , Zea mays/genética , Zea mays/química , Proteínas de Plantas/genética , Bases de Datos de Proteínas , Péptidos/genética , Péptidos/química , Genoma de Planta , Proteoma/genética , Proteoma/análisis , Proteómica/métodos
17.
J Proteome Res ; 23(1): 185-214, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38104260

RESUMEN

This study describes a new release of the Arabidopsis thaliana PeptideAtlas proteomics resource (build 2023-10) providing protein sequence coverage, matched mass spectrometry (MS) spectra, selected post-translational modifications (PTMs), and metadata. 70 million MS/MS spectra were matched to the Araport11 annotation, identifying ∼0.6 million unique peptides and 18,267 proteins at the highest confidence level and 3396 lower confidence proteins, together representing 78.6% of the predicted proteome. Additional identified proteins not predicted in Araport11 should be considered for the next Arabidopsis genome annotation. This release identified 5198 phosphorylated proteins, 668 ubiquitinated proteins, 3050 N-terminally acetylated proteins, and 864 lysine-acetylated proteins and mapped their PTM sites. MS support was lacking for 21.4% (5896 proteins) of the predicted Araport11 proteome: the "dark" proteome. This dark proteome is highly enriched for E3 ligases, transcription factors, and for certain (e.g., CLE, IDA, PSY) but not other (e.g., THIONIN, CAP) signaling peptides families. A machine learning model trained on RNA expression data and protein properties predicts the probability that proteins will be detected. The model aids in discovery of proteins with short half-life (e.g., SIG1,3 and ERF-VII TFs) and for developing strategies to identify the missing proteins. PeptideAtlas is linked to TAIR, tracks in JBrowse, and several other community proteomics resources.


Asunto(s)
Arabidopsis , Humanos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteoma/análisis , Espectrometría de Masas en Tándem/métodos , Procesamiento Proteico-Postraduccional , Péptidos/análisis , Bases de Datos de Proteínas
18.
J Cell Mol Med ; 28(9): e18319, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38742846

RESUMEN

Knee osteoarthritis (KOA), a major health and economic problem facing older adults worldwide, is a degenerative joint disease. Glycyrrhiza uralensis Fisch. (GC) plays an integral role in many classic Chinese medicine prescriptions for treating knee osteoarthritis. Still, the role of GC in treating KOA is unclear. To explore the pharmacological mechanism of GC against KOA, UPLC-Q-TOF/MS was conducted to detect the main compounds in GC. The therapeutic effect of GC on DMM-induced osteoarthritic mice was assessed by histomorphology, µCT, behavioural tests, and immunohistochemical staining. Network pharmacology and molecular docking were used to predict the potential targets of GC against KOA. The predicted results were verified by immunohistochemical staining Animal experiments showed that GC had a protective effect on DMM-induced KOA, mainly in the improvement of movement disorders, subchondral bone sclerosis and cartilage damage. A variety of flavonoids and triterpenoids were detected in GC via UPLC-Q-TOF/MS, such as Naringenin. Seven core targets (JUN, MAPK3, MAPK1, AKT1, TP53, RELA and STAT3) and three main pathways (IL-17, NF-κB and TNF signalling pathways) were discovered through network pharmacology analysis that closely related to inflammatory response. Interestingly, molecular docking results showed that the active ingredient Naringenin had a good binding effect on anti-inflammatory-related proteins. In the verification experiment, after the intervention of GC, the expression levels of pp65 and F4/80 inflammatory indicators in the knee joint of KOA model mice were significantly downregulated. GC could improve the inflammatory environment in DMM-induced osteoarthritic mice thus alleviating the physiological structure and dysfunction of the knee joint. GC might play an important role in the treatment of knee osteoarthritis.


Asunto(s)
Glycyrrhiza uralensis , Simulación del Acoplamiento Molecular , Farmacología en Red , Osteoartritis de la Rodilla , Animales , Glycyrrhiza uralensis/química , Ratones , Osteoartritis de la Rodilla/tratamiento farmacológico , Osteoartritis de la Rodilla/metabolismo , Osteoartritis de la Rodilla/patología , Masculino , Modelos Animales de Enfermedad , Transducción de Señal/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Ratones Endogámicos C57BL
19.
Circulation ; 148(22): 1750-1763, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-37877288

RESUMEN

BACKGROUND: The plant-based Portfolio dietary pattern includes recognized cholesterol-lowering foods (ie, plant protein, nuts, viscous fiber, phytosterols, and plant monounsaturated fats) shown to improve several cardiovascular disease (CVD) risk factors in randomized controlled trials. However, there is limited evidence on the role of long-term adherence to the diet and CVD risk. The primary objective was to examine the relationship between the Portfolio Diet Score (PDS) and the risk of total CVD, coronary heart disease (CHD), and stroke. METHODS: We prospectively followed 73 924 women in the Nurses' Health Study (1984-2016), 92 346 women in the Nurses' Health Study II (1991-2017), and 43 970 men in the Health Professionals Follow-up Study (1986-2016) without CVD or cancer at baseline. Diet was assessed using validated food frequency questionnaires at baseline and every 4 years using a PDS that positively ranks plant protein (legumes), nuts and seeds, viscous fiber sources, phytosterols (mg/day), and plant monounsaturated fat sources, and negatively ranks foods high in saturated fat and cholesterol. RESULTS: During up to 30 years of follow-up, 16 917 incident CVD cases, including 10 666 CHD cases and 6473 strokes, were documented. After multivariable adjustment for lifestyle factors and a modified Alternate Healthy Eating Index (excluding overlapping components), comparing the highest with the lowest quintile, participants with a higher PDS had a lower risk of total CVD (pooled hazard ratio [HR], 0.86 [95% CI, 0.81-0.92]; Ptrend<0.001), CHD (pooled HR, 0.86 [95% CI, 0.80-0.93]; Ptrend=0.0001), and stroke (pooled HR, 0.86 [95% CI, 0.78-0.95]; Ptrend=0.0003). In addition, a 25-percentile higher PDS was associated with a lower risk of total CVD (pooled HR, 0.92 [95% CI, 0.89-0.95]), CHD (pooled HR, 0.92 [95% CI, 0.88-0.95]), and stroke (pooled HR, 0.92 [95% CI, 0.87-0.96]). Results remained consistent across sensitivity and most subgroup analyses, and there was no evidence of departure from linearity for CVD, CHD, or stroke. In a subset of participants, a higher PDS was associated with a more favorable blood lipid and inflammatory profile. CONCLUSIONS: The PDS was associated with a lower risk of CVD, including CHD and stroke, and a more favorable blood lipid and inflammatory profile, in 3 large prospective cohorts.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad Coronaria , Fitosteroles , Accidente Cerebrovascular , Masculino , Humanos , Femenino , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Estudios Prospectivos , Estudios de Seguimiento , Dieta , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/prevención & control , Colesterol , Proteínas de Plantas , Accidente Cerebrovascular/complicaciones , Factores de Riesgo
20.
Stroke ; 55(1): 50-58, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134264

RESUMEN

BACKGROUND: The effect of marine omega-3 PUFAs on risk of stroke remains unclear. METHODS: We investigated the associations between circulating and tissue omega-3 PUFA levels and incident stroke (total, ischemic, and hemorrhagic) in 29 international prospective cohorts. Each site conducted a de novo individual-level analysis using a prespecified analytical protocol with defined exposures, covariates, analytical methods, and outcomes; the harmonized data from the studies were then centrally pooled. Multivariable-adjusted HRs and 95% CIs across omega-3 PUFA quintiles were computed for each stroke outcome. RESULTS: Among 183 291 study participants, there were 10 561 total strokes, 8220 ischemic strokes, and 1142 hemorrhagic strokes recorded over a median of 14.3 years follow-up. For eicosapentaenoic acid, comparing quintile 5 (Q5, highest) with quintile 1 (Q1, lowest), total stroke incidence was 17% lower (HR, 0.83 [CI, 0.76-0.91]; P<0.0001), and ischemic stroke was 18% lower (HR, 0.82 [CI, 0.74-0.91]; P<0.0001). For docosahexaenoic acid, comparing Q5 with Q1, there was a 12% lower incidence of total stroke (HR, 0.88 [CI, 0.81-0.96]; P=0.0001) and a 14% lower incidence of ischemic stroke (HR, 0.86 [CI, 0.78-0.95]; P=0.0001). Neither eicosapentaenoic acid nor docosahexaenoic acid was associated with a risk for hemorrhagic stroke. These associations were not modified by either baseline history of AF or prevalent CVD. CONCLUSIONS: Higher omega-3 PUFA levels are associated with lower risks of total and ischemic stroke but have no association with hemorrhagic stroke.


Asunto(s)
Ácidos Grasos Omega-3 , Accidente Cerebrovascular Hemorrágico , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Estudios Prospectivos , Ácido Eicosapentaenoico , Ácidos Docosahexaenoicos , Accidente Cerebrovascular Hemorrágico/epidemiología , Accidente Cerebrovascular/epidemiología , Factores de Riesgo
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