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1.
Nature ; 634(8034): 579-584, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39358510

RESUMEN

The Ruddlesden-Popper (R-P) bilayer nickelate, La3Ni2O7, was recently found to show signatures of high-temperature superconductivity (HTSC) at pressures above 14 GPa (ref. 1). Subsequent investigations achieved zero resistance in single-crystalline and polycrystalline samples under hydrostatic pressure conditions2-4. Yet, obvious diamagnetic signals, the other hallmark of superconductors, are still lacking owing to the filamentary nature with low superconducting volume fraction2,4,5. The presence of a new 1313 polymorph and competing R-P phases obscured proper identification of the phase for HTSC6-9. Thus, achieving bulk HTSC and identifying the phase at play are the most prominent tasks. Here we address these issues in the praseodymium (Pr)-doped La2PrNi2O7 polycrystalline samples. We find that substitutions of Pr for La effectively inhibit the intergrowth of different R-P phases, resulting in a nearly pure bilayer structure. For La2PrNi2O7, pressure-induced orthorhombic to tetragonal structural transition takes place at Pc ≈ 11 GPa, above which HTSC emerges gradually on further compression. The superconducting transition temperatures at 18-20 GPa reach T c onset = 82.5 K and T c zero = 60 K , which are the highest values, to our knowledge, among known nickelate superconductors. Importantly, bulk HTSC was testified by detecting clear diamagnetic signals below about 75 K with appreciable superconducting shielding volume fractions at a pressure of above 15 GPa. Our results not only resolve the existing controversies but also provide directions for exploring bulk HTSC in the bilayer nickelates.

2.
Nature ; 632(8027): 1032-1037, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39198671

RESUMEN

Superconductivity in a highly correlated kagome system has been theoretically proposed for years (refs. 1-5), yet the experimental realization is hard to achieve6,7. The recently discovered vanadium-based kagome materials8, which exhibit both superconductivity9-11 and charge-density-wave orders12-14, are nonmagnetic8,9 and weakly correlated15,16. Thus these materials are unlikely to host the exotic superconductivity theoretically proposed. Here we report the discovery of a chromium-based kagome metal, CsCr3Sb5, which is contrastingly featured with strong electron correlations, frustrated magnetism and characteristic flat bands close to the Fermi level. Under ambient pressure, this kagome metal undergoes a concurrent structural and magnetic phase transition at 55 K, with a stripe-like 4a0 structural modulation. At high pressure, the phase transition evolves into two transitions, possibly associated with charge-density-wave and antiferromagnetic spin-density-wave orderings. These density-wave-like orders are gradually suppressed with pressure and, remarkably, a superconducting dome emerges at 3.65-8.0 GPa. The maximum of the superconducting transition temperature, Tcmax = 6.4 K, appears when the density-wave-like orders are completely suppressed at 4.2 GPa, and the normal state exhibits a non-Fermi-liquid behaviour, reminiscent of unconventional superconductivity and quantum criticality in iron-based superconductors17,18. Our work offers an unprecedented platform for investigating superconductivity in correlated kagome systems.

3.
Development ; 151(12)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38814747

RESUMEN

The shoot apical meristem (SAM) gives rise to the aboveground organs of plants. The size of the SAM is relatively constant due to the balance between stem cell replenishment and cell recruitment into new organs. In angiosperms, the transcription factor WUSCHEL (WUS) promotes stem cell proliferation in the central zone of the SAM. WUS forms a negative feedback loop with a signaling pathway activated by CLAVATA3 (CLV3). In the periphery of the SAM, the ERECTA family receptors (ERfs) constrain WUS and CLV3 expression. Here, we show that four ligands of ERfs redundantly inhibit the expression of these two genes. Transcriptome analysis confirmed that WUS and CLV3 are the main targets of ERf signaling and uncovered new ones. Analysis of promoter reporters indicated that the WUS expression domain mostly overlaps with the CLV3 domain and does not shift along the apical-basal axis in clv3 mutants. Our three-dimensional mathematical model captured gene expression distributions at the single-cell level under various perturbed conditions. Based on our findings, CLV3 regulates cellular levels of WUS mostly through autocrine signaling, and ERfs regulate the spatial expression of WUS, preventing its encroachment into the peripheral zone.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Regulación de la Expresión Génica de las Plantas , Proteínas de Homeodominio , Meristema , Transducción de Señal , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Meristema/metabolismo , Meristema/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Transducción de Señal/genética , Proteínas de Homeodominio/metabolismo , Proteínas de Homeodominio/genética , Receptores de Superficie Celular/metabolismo , Receptores de Superficie Celular/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Modelos Biológicos
4.
Hum Mol Genet ; 32(7): 1137-1151, 2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-36331344

RESUMEN

Mitochondrial dynamics is essential for maintaining the physiological function of the mitochondrial network, and its disorders lead to a variety of diseases. Our previous study identified mitochondrial dynamics controlled anti-tumor immune responses and anxiety symptoms. However, how mitochondrial dynamics affects auditory function in the inner ear remains unclear. Here, we show that the deficiency of FAM73a or FAM73b, two mitochondrial outer membrane proteins that mediate mitochondrial fusion, leads to outer hair cells (HCs) damage and progressive hearing loss in FVB/N mice. Abnormal mitochondrial fusion causes elevated oxidative stress and apoptosis of HCs in the early stage. Thereafter, the activation of macrophages and CD4+ T cell is found in the mutant mice with the increased expression of the inflammatory cytokines IL-12 and IFN-γ compared with control mice. Strikingly, a dramatically decreased number of macrophages by Clophosome®-A-Clodronate Liposomes treatment alleviates the hearing loss of mutant mice. Collectively, our finding highlights that FAM73a or FAM73b deficiency affects HCs survival by disturbing the mitochondrial function, and the subsequent immune response in the cochleae worsens the damage of HCs.


Asunto(s)
Pérdida Auditiva , Dinámicas Mitocondriales , Animales , Ratones , Dinámicas Mitocondriales/genética , Audición , Pérdida Auditiva/genética , Pérdida Auditiva/metabolismo , Células Ciliadas Auditivas Externas/metabolismo , Inmunidad
5.
Mol Ther ; 32(5): 1387-1406, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38414247

RESUMEN

Cisplatin-induced hearing loss is a common side effect of cancer chemotherapy in clinics; however, the mechanism of cisplatin-induced ototoxicity is still not completely clarified. Cisplatin-induced ototoxicity is mainly associated with the production of reactive oxygen species, activation of apoptosis, and accumulation of intracellular lipid peroxidation, which also is involved in ferroptosis induction. In this study, the expression of TfR1, a ferroptosis biomarker, was upregulated in the outer hair cells of cisplatin-treated mice. Moreover, several key ferroptosis regulator genes were altered in cisplatin-damaged cochlear explants based on RNA sequencing, implying the induction of ferroptosis. Ferroptosis-related Gpx4 and Fsp1 knockout mice were established to investigate the specific mechanisms associated with ferroptosis in cochleae. Severe outer hair cell loss and progressive damage of synapses in inner hair cells were observed in Atoh1-Gpx4-/- mice. However, Fsp1-/- mice showed no significant hearing phenotype, demonstrating that Gpx4, but not Fsp1, may play an important role in the functional maintenance of HCs. Moreover, findings showed that FDA-approved luteolin could specifically inhibit ferroptosis and alleviate cisplatin-induced ototoxicity through decreased expression of transferrin and intracellular concentration of ferrous ions. This study indicated that ferroptosis inhibition through the reduction of intracellular ferrous ions might be a potential strategy to prevent cisplatin-induced hearing loss.


Asunto(s)
Cisplatino , Ferroptosis , Pérdida Auditiva , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Animales , Cisplatino/efectos adversos , Ferroptosis/efectos de los fármacos , Ferroptosis/genética , Ratones , Pérdida Auditiva/inducido químicamente , Pérdida Auditiva/genética , Pérdida Auditiva/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/genética , Modelos Animales de Enfermedad , Receptores de Transferrina/metabolismo , Receptores de Transferrina/genética , Especies Reactivas de Oxígeno/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Células Ciliadas Auditivas Externas/metabolismo , Células Ciliadas Auditivas Externas/efectos de los fármacos , Células Ciliadas Auditivas Externas/patología , Ototoxicidad/etiología , Ototoxicidad/metabolismo , Antineoplásicos/efectos adversos , Apoptosis/efectos de los fármacos
6.
Dev Biol ; 495: 54-62, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36610533

RESUMEN

Stickler syndrome is a multisystem collagenopathy with affected individuals exhibiting a high rate of ocular complications. Lysyl oxidase-like 3 (LOXL3) is a human disease gene candidate with a critical role in catalyzing collagen crosslinking. A homozygous missense variant of LOXL3 was reported in Stickler syndrome with severe myopia. However, the underlying mechanisms of the LOXL3 missense mutation that causes Stickler syndrome are unknown. In this study, a mouse model of Stickler syndrome induced by LOXL3 mutation (c.2027G â€‹> â€‹A, p.Cys676Try) was obtained using CRISPR/Cas9 gene editing techniques. The Loxl3 mutant mice exhibited perinatal death, spinal deformity, and cleft palate, and Loxl3 mutation also induced skeletal dysplasia and progressive visual degeneration. Furthermore, we observed the damage of the bruch's membrane (BrM) and an increase in the levels of glial fibrillary acidic protein (GFAP) and Rpe65 in the Loxl3 mutant mice. Thus, we provided the critical in vivo evidence that Loxl3 possibly has a pivotal role in maintaining the eye function.


Asunto(s)
Enfermedades del Tejido Conjuntivo , Enfermedades Hereditarias del Ojo , Desprendimiento de Retina , Femenino , Embarazo , Humanos , Animales , Ratones , Aminoácido Oxidorreductasas/genética , Aminoácido Oxidorreductasas/metabolismo , Desprendimiento de Retina/genética , Enfermedades del Tejido Conjuntivo/genética , Retina/metabolismo , Mutación/genética
7.
Br J Haematol ; 204(4): 1219-1226, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38180132

RESUMEN

Venetoclax (VEN) in combination with hypomethylating agents (HMAs) is considered the standard of treatment for individuals with newly diagnosed acute myeloid leukaemia (AML) who are ineligible for intensive chemotherapy. We conducted a retrospective analysis that encompassed 16 critically ill patients newly diagnosed with AML who were admitted to the intensive care unit (ICU) and received the VEN and HMA regimen. Among them, 13 were primary AML, and three were MDS-transformed AML. The mean Acute Physiology and Chronic Health Evaluation II (APACHE II) score was 18.9, and the mean sepsis-related organ failure assessment score (SOFA) was 6.2. The average length of the ICU stay was 27.3 days. The median duration of VEN administration was 16 days. After the first course of VEN + HMA, 12 cases (75%) achieved complete remission (CR) or CR with incomplete haematological recovery (CRi). Among the five patients harbouring TP53 mutations, the overall response rate (ORR) was 90%. All patients experienced grade 3-4 haematological adverse events (AEs). With a median follow-up of 9.5 months (range: 0.5-23), the overall survival (OS) rate was 43.75%. TP53-wild patients and CR state after the first course of VEN-HMA indicated better survival. The combination of VEN and HMA has demonstrated a significantly elevated therapeutic response rate in newly diagnosed AML patients with critical illness.


Asunto(s)
Enfermedad Crítica , Leucemia Mieloide Aguda , Sulfonamidas , Humanos , Estudios Retrospectivos , Compuestos Bicíclicos Heterocíclicos con Puentes/efectos adversos , Leucemia Mieloide Aguda/genética , Respuesta Patológica Completa , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
8.
Inorg Chem ; 63(18): 8206-8214, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38647176

RESUMEN

The accessibility of multiple valence states of americium (Am) inspired redox-based protocols aimed at efficient separation of trivalent Am (Am3+) from trivalent lanthanides (Ln3+) alternative to the traditional liquid-liquid extraction. This requires an extensive understanding of the coordination chemistry of Am in its various accessible valence states in the aqueous phase. In this work, by means of DFT calculations, the coordination of AmIII-VI with five typical N-donor ligands, i.e., terpyridine (tpy), bispyrazinylpyridine (dpp), bistriazinylpyridine (BTP), bistriazinyl bipyridine (BTBP), and bistrazinyl phenanthroline (BTPhen), was studied in terms of energy and topological analysis. The results show that the exchange of aqua ligands of hydrated ions by N-donor ligands is an entropy-driven process and enthalpically unfavorable. Topological analysis suggests a distinct mechanism of BTP to modulate the redox potential of Am(III) in that BTP can assist the relay of the leaving electron of AmIII, while the other N-donor ligands can detain the oxidation of Am by offering their electron instead. This comparative study enriches our understanding of the coordination chemistry of high-valent Am with N-donor ligands and recommends the ligand design toward the modulation of redox potentials of hydrated Am(III) ions.

9.
Inorg Chem ; 63(2): 923-927, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38156893

RESUMEN

Plain simulations and enhanced sampling unveil a novel siderocalin (Scn) recognition mode for An-Ent (where An = actinides and Ent = enterobactin) complexes and identify a "seesaw" relationship between actinide affinity to Ent and Scn recognition to an An-Ent complex. Electrostatic interactions predominantly govern competitive binding in both processes. Additionally, hydrolysis-induced negative charge, water expulsion-driven entropy, and Ent's conformational adaptability collectively enhance high-affinity recognition.

10.
Phys Chem Chem Phys ; 26(28): 19543-19553, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38979972

RESUMEN

Rational design of γ-alumina-based catalysts relies on an extensive understanding of the distribution of hydroxyl groups on the surface of γ-alumina and their physicochemical properties, which remain unclear and challenging to determine experimentally due to the structural complexity. In this work, by means of DFT and thermodynamic calculations, various hydroxylation modes of γ-alumina (110) and (100) surfaces at different OH coverages were evaluated, based on which a thermodynamic model to reflect the relationship between temperature and the surface structure was established and the stable hydroxylation modes under experimental conditions were predicted. This enables us to identify the experimentally measured IR spectra. The effect of hydroxyl coverages on the surface Lewis acidity was then analyzed, showing that the presence of hydroxyl groups could promote the Lewis acidity of neighboring Al sites. This work provides fundamental insights into the molecular level understanding of the surface properties of γ-alumina and benefits the rational design of alumina-based catalysts.

11.
J Biochem Mol Toxicol ; 38(8): e23800, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-39132781

RESUMEN

Pyroglutamate (pE)-modified amyloid-ß (Aß) peptides play a crucial role in the development of Alzheimer's disease. pEAß3-42 can rapidly form oligomers that gradually elongate hydrophobic segments to form ß-sheet-rich amyloid intermediates, ultimately resulting in the formation of mature amyloid fibrils. pEAß3-42 can also catalyze the aggregation of Aß species and subsequently accelerate the formation of amyloid senile plaques. Considering the recent clinical success of the pEAß3-42-targeting antibody donanemab, molecules that strongly bind pEAß3-42 and prevent its aggregation and catalytic effect on Aßs may also provide potential therapeutic options for Alzheimer's disease. Here, we demonstrate that the natural antibiotic cyclopeptide tyrocidine A (TA) not only strongly inhibits the aggregation of Aß1-42 as previously reported, but also interacts with the hydrophobic C-terminus and middle domain of pEAß3-42 to maintain an unordered conformation, effectively impeding the formation of initial oligomers and subsequently halting the aggregation of pEAß3-42. Furthermore, TA can disrupt the "catalytic effect" of pEAß3-42 on amyloid aggregates, effectively suppressing Aß aggregation and ultimately preventing the pathological events induced by Aßs.


Asunto(s)
Péptidos beta-Amiloides , Interacciones Hidrofóbicas e Hidrofílicas , Ácido Pirrolidona Carboxílico , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/química , Ácido Pirrolidona Carboxílico/química , Ácido Pirrolidona Carboxílico/análogos & derivados , Ácido Pirrolidona Carboxílico/farmacología , Humanos , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Agregado de Proteínas/efectos de los fármacos , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico
12.
J Phys Chem A ; 128(9): 1656-1664, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38394031

RESUMEN

Oxidative dehydrogenation (ODH) of light alkanes is a key process in the oxidative conversion of alkanes to alkenes, oxygenated hydrocarbons, and COx (x = 1,2). Understanding the underlying mechanisms extensively is crucial to keep the ODH under control for target products, e.g., alkenes rather than COx, with minimal energy consumption, e.g., during the alkene production or maximal energy release, e.g., during combustion. In this work, deep potential (DP), a neural network atomic potential developed in recent years, was employed to conduct large-scale accurate reactive dynamic simulations. The model was trained on a sufficient data set obtained at the density functional theory level. The intricate reaction network was elucidated and organized in the form of a hierarchical network to demonstrate the key features of the ODH mechanisms, including the activation of propane and oxygen, the influence of propyl reaction pathways on the propene selectivity, and the role of rapid H2O2 decomposition for sustainable and efficient ODH reactions. The results indicate the more complex reaction mechanism of propane ODH than that of ethane ODH and are expected to provide insights in the ODH catalyst optimization. In addition, this work represents the first application of deep potential in the ODH mechanistic study and demonstrates the ample advantages of DP in the study of mechanism and dynamics of complex systems.

13.
Plant Cell Rep ; 43(5): 125, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647720

RESUMEN

KEY MESSAGE: The interaction network and pathway map uncover the potential crosstalk between sugar and hormone metabolisms as a possible reason for leaf senescence in P. ternata. Pinellia ternata, an environmentally sensitive medicinal plant, undergoes leaf senescence twice a year, affecting its development and yield. Understanding the potential mechanism that delays leaf senescence could theoretically decrease yield losses. In this study, a typical senescent population model was constructed, and an integrated analysis of transcriptomic and metabolomic profiles of P. ternata was conducted using two early leaf senescence populations and two stay-green populations. The result showed that two key gene modules were associated with leaf senescence which were mainly enriched in sugar and hormone signaling pathways, respectively. A network constructed by unigenes and metabolisms related to the obtained two pathways revealed that several compounds such as D-arabitol and 2MeScZR have a higher significance ranking. In addition, a total of 130 hub genes in this network were categorized into 3 classes based on connectivity. Among them, 34 hub genes were further analyzed through a pathway map, the potential crosstalk between sugar and hormone metabolisms might be an underlying reason of leaf senescence in P. ternata. These findings address the knowledge gap regarding leaf senescence in P. ternata, providing candidate germplasms for molecular breeding and laying theoretical basis for the realization of finely regulated cultivation in future.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Metabolómica , Pinellia , Reguladores del Crecimiento de las Plantas , Hojas de la Planta , Transcriptoma , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Pinellia/genética , Pinellia/metabolismo , Pinellia/fisiología , Pinellia/crecimiento & desarrollo , Reguladores del Crecimiento de las Plantas/metabolismo , Transcriptoma/genética , Senescencia de la Planta/genética , Perfilación de la Expresión Génica , Azúcares/metabolismo , Metaboloma/genética , Redes Reguladoras de Genes , Metabolismo de los Hidratos de Carbono/genética
14.
Chem Biodivers ; 21(6): e202400519, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38576052

RESUMEN

One new highly degraded steroid, namely 21-nor-4-ene-chaxine A (1) furnishing a 5/6/5-tricyclic, along with one known related analogue (2), were isolated from the South China Sea sponge Spongia officinalis. Their structures including absolute configurations were established by extensive spectroscopic data analysis, TDDFT-ECD calculation, and comparison with the spectral data previously reported in the literature. Compound 1 represent the new member of incisterols family with a highly degradation in ring B. In vitro bioassays revealed compound 2 exhibited significant anti-microglial inflammatory effect on lipopolysaccharide (LPS)-induced inflammation in BV-2 microglial cells.


Asunto(s)
Antiinflamatorios , Lipopolisacáridos , Poríferos , Esteroides , Animales , Poríferos/química , Esteroides/química , Esteroides/aislamiento & purificación , Esteroides/farmacología , Lipopolisacáridos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Ratones , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , China , Microglía/efectos de los fármacos , Microglía/metabolismo , Microglía/citología , Línea Celular , Conformación Molecular , Estructura Molecular
15.
Molecules ; 29(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38999191

RESUMEN

Organic pollutants were one of the main sources of environmental pollutants. The degradation of organic pollutants through photocatalytic technology was one of the effective solutions. By preparing zinc oxide(ZnO) nanowires modified with sodium-doped conjugated 2,4,6-triaminopyrimidin-g-C3N4 (NaTCN) heterojunction (ZnO/NaTCN), the photocatalytic performance of NaTCN modified with different ratios of ZnO was systematically studied. The photocatalytic performance was studied through the degradation performance of methyl blue (MB) dye. The results showed that 22.5 wt% ZnO/NaTCN had the best degradation effect on MB dye. The degradation rate of MB reached 98.54% in 70 min. After three cycles, it shows good cycling stability (degradation rate is 96.99%) for dye degradation. It was found that there are two types of active species: ·OH and h+, of which h+ is the main active species produced by photocatalytic degradation of dyes. The excellent degradation performance was attributed to the fact that ZnO facilitated the extraction and transport of photogenerated carriers. The doping of sodium facilitated charge transfer. The NaTCN conjugated system promoted the extraction and transfer of photogenerated carriers. It provided guidance for designing efficient composite catalysts for use in other renewable energy fields.

16.
Molecules ; 29(9)2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38731650

RESUMEN

The present study investigates the chemical composition variances among Pinelliae Rhizoma, a widely used Chinese herbal medicine, and its common adulterants including Typhonium flagelliforme, Arisaema erubescens, and Pinellia pedatisecta. Utilizing the non-targeted metabolomics technique of employing UHPLC-Q-Orbitrap HRMS, this research aims to comprehensively delineate the metabolic profiles of Pinelliae Rhizoma and its adulterants. Multivariate statistical methods including PCA and OPLS-DA are employed for the identification of differential metabolites. Volcano plot analysis is utilized to discern upregulated and downregulated compounds. KEGG pathway analysis is conducted to elucidate the differences in metabolic pathways associated with these compounds, and significant pathway enrichment analysis is performed. A total of 769 compounds are identified through metabolomics analysis, with alkaloids being predominant, followed by lipids and lipid molecules. Significant differential metabolites were screened out based on VIP > 1 and p-value < 0.05 criteria, followed by KEGG enrichment analysis of these differential metabolites. Differential metabolites between Pinelliae Rhizoma and Typhonium flagelliforme, as well as between Pinelliae Rhizoma and Pinellia pedatisecta, are significantly enriched in the biosynthesis of amino acids and protein digestion and absorption pathways. Differential metabolites between Pinelliae Rhizoma and Arisaema erubescens are mainly enriched in tyrosine metabolism and phenylalanine metabolism pathways. These findings aim to provide valuable data support and theoretical references for further research on the pharmacological substances, resource development and utilization, and quality control of Pinelliae Rhizoma.


Asunto(s)
Metabolómica , Pinellia , Rizoma , Cromatografía Líquida de Alta Presión/métodos , Metabolómica/métodos , Pinellia/metabolismo , Pinellia/química , Rizoma/metabolismo , Rizoma/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/metabolismo , Espectrometría de Masas/métodos , Contaminación de Medicamentos , Metaboloma , Redes y Vías Metabólicas
17.
Angew Chem Int Ed Engl ; 63(18): e202402236, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38357746

RESUMEN

Environmentally friendly electrocatalytic coupling of CO2 and N2 for urea synthesis is a promising strategy. However, it is still facing problems such as low yield as well as low stability. Here, a new carbon-coated liquid alloy catalyst, Ga79Cu11Mo10@C is designed for efficient electrochemical urea synthesis by activating Ga active sites. During the N2 and CO2 co-reduction process, the yield of urea reaches 28.25 mmol h-1 g-1, which is the highest yield reported so far under the same conditions, the Faraday efficiency (FE) is also as high as 60.6 % at -0.4 V vs. RHE. In addition, the catalyst shows excellent stability under 100 h of testing. Comprehensive analyses showed that sequential exposure of a high density of active sites promoted the adsorption and activation of N2 and CO2 for efficient coupling reactions. This coupling reaction occurs through a thermodynamic spontaneous reaction between *N=N* and CO to form a C-N bond. The deformability of the liquid state facilitates catalyst recovery and enhances stability and resistance to poisoning. Moreover, the introduction of Cu and Mo stimulates the Ga active sites, which successfully synthesises the *NCON* intermediate. The reaction energy barrier of the third proton-coupled electron transfer process rate-determining step (RDS) *NHCONH→*NHCONH2 was lowered, ensuring the efficient synthesis of urea.

18.
Small ; 19(15): e2207202, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36683197

RESUMEN

As an important multiferroic material, pure and low-dimensional phase-stable bismuth ferrite has wide applications. Herein, one-pot hydrothermal method was used to synthesize bismuth ferrite. Almost pure Bi2 Fe4 O9 , BiFeO3 , and their mixture were successfully obtained by controlling the KOH concentration in the hydrothermal solutions. The as-prepared Bi2 Fe4 O9 products were crystalline with Pbam space group, had nanosheet morphology, and tended to aggregate into nanofloret or random stacking. Each Bi2 Fe4 O9 nanosheet was a single crystal with (001) plane as its exposed surface. Single unit-cell layered Bi2 Fe4 O9 nanosheets had a uniform thickness of 1 nm. The surface energies of various (100), (010), and (001) planes were 3.6-4.0, 5.6-15.1, and 1.7-3.0 J m-2 , respectively, in the Bi2 Fe4 O9 crystal. The formation mechanism and structural model of the as-prepared single unit-cell layered Bi2 Fe4 O9 nanosheets have been given. The growth of Bi2 Fe4 O9 nanosheets was discussed. Thermal analysis showed that the Bi2 Fe4 O9 phase was stable up to 1260 K. The thermal expansion behavior of the Bi2 Fe4 O9 nanosheet was nonlinear. The thermal expansion coefficients of the ultrathin Bi2 Fe4 O9 nanosheets on the a-, b-, c-axes, and on the unit-cell volume V were determined, showing an anisotropic thermal expansion behavior. This study is helpful for the controllable synthesis of ultrathin Bi2 Fe4 O9 nanosheets.

19.
Opt Express ; 31(5): 8384-8392, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36859953

RESUMEN

Bound states in the continuum (BICs) have been widely observed in many symmetric geometries in the optical system during the last decade. Here, we consider a scenario in which the structure is designed asymmetrically with anisotropic birefringent material embedded in one-dimensional photonic crystals. This kind of new shape opens the possibility of obtaining symmetry-protected BICs (SP-BICs) and Friedrich-Wintgen BICs (FW-BICs) form in tunable anisotropy axis tilt. Interestingly, these BICs can be observed as high-Q resonances by variation of the system's parameters, such as the incident angle, which means the structure without being injected at Brewster's angle can also achieve BICs. Our findings might achieve active regulation and are easy to manufacture.

20.
Respir Res ; 24(1): 299, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017476

RESUMEN

OBJECTIVES: Parametric response mapping (PRM) enables the evaluation of small airway disease (SAD) at the voxel level, but requires both inspiratory and expiratory chest CT scans. We hypothesize that deep learning PRM from inspiratory chest CT scans can effectively evaluate SAD in individuals with normal spirometry. METHODS: We included 537 participants with normal spirometry, a history of smoking or secondhand smoke exposure, and divided them into training, tuning, and test sets. A cascaded generative adversarial network generated expiratory CT from inspiratory CT, followed by a UNet-like network predicting PRM using real inspiratory CT and generated expiratory CT. The performance of the prediction is evaluated using SSIM, RMSE and dice coefficients. Pearson correlation evaluated the correlation between predicted and ground truth PRM. ROC curves evaluated predicted PRMfSAD (the volume percentage of functional small airway disease, fSAD) performance in stratifying SAD. RESULTS: Our method can generate expiratory CT of good quality (SSIM 0.86, RMSE 80.13 HU). The predicted PRM dice coefficients for normal lung, emphysema, and fSAD regions are 0.85, 0.63, and 0.51, respectively. The volume percentages of emphysema and fSAD showed good correlation between predicted and ground truth PRM (|r| were 0.97 and 0.64, respectively, p < 0.05). Predicted PRMfSAD showed good SAD stratification performance with ground truth PRMfSAD at thresholds of 15%, 20% and 25% (AUCs were 0.84, 0.78, and 0.84, respectively, p < 0.001). CONCLUSION: Our deep learning method generates high-quality PRM using inspiratory chest CT and effectively stratifies SAD in individuals with normal spirometry.


Asunto(s)
Asma , Aprendizaje Profundo , Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Tomografía Computarizada por Rayos X/métodos , Pulmón/diagnóstico por imagen
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