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1.
Nat Mater ; 22(11): 1387-1393, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37735526

RESUMO

Zeolitic imidazolate frameworks (ZIFs) are a subset of metal-organic frameworks with more than 200 characterized crystalline and amorphous networks made of divalent transition metal centres (for example, Zn2+ and Co2+) linked by imidazolate linkers. ZIF thin films have been intensively pursued, motivated by the desire to prepare membranes for selective gas and liquid separations. To achieve membranes with high throughput, as in ångström-scale biological channels with nanometre-scale path lengths, ZIF films with the minimum possible thickness-down to just one unit cell-are highly desired. However, the state-of-the-art methods yield membranes where ZIF films have thickness exceeding 50 nm. Here we report a crystallization method from ultradilute precursor mixtures, which exploits registry with the underlying crystalline substrate, yielding (within minutes) crystalline ZIF films with thickness down to that of a single structural building unit (2 nm). The film crystallized on graphene has a rigid aperture made of a six-membered zinc imidazolate coordination ring, enabling high-permselective H2 separation performance. The method reported here will probably accelerate the development of two-dimensional metal-organic framework films for efficient membrane separation.

2.
Rheumatology (Oxford) ; 63(SI2): SI249-SI259, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38317060

RESUMO

BACKGROUND: The genetic architecture of JIA remains only partially comprehended. There is a clear imperative for continued endeavours to uncover insights into the underlying causes of JIA. METHODS: This study encompassed a comprehensive spectrum of endeavours, including conducting a JIA genome-wide association study (GWAS) meta-analysis that incorporated data from 4550 JIA cases and 18 446 controls. We employed in silico and genome-editing approaches to prioritizing target genes. To investigate pleiotropic effects, we conducted phenome-wide association studies. Cell-type enrichment analyses were performed by integrating bulk and single-cell sequencing data. Finally, we delved into potential druggable targets for JIA. RESULTS: Fourteen genome-wide significant non-HLA loci were identified, including four novel loci, each exhibiting pleiotropic associations with other autoimmune diseases or musculoskeletal traits. We uncovered strong genetic correlation between JIA and BMD traits at 52 genomic regions, including three GWAS loci for JIA. Candidate genes with immune functions were captured by in silico analyses at each novel locus, with additional findings identified through our experimental approach. Cell-type enrichment analysis revealed 21 specific immune cell types crucial for the affected organs in JIA, indicating their potential contribution to the disease. Finally, 24 known or candidate druggable target genes were prioritized. CONCLUSIONS: Our identification of four novel JIA-associated genes, CD247, RHOH, COLEC10 and IRF8, broadens the novel potential drug repositioning opportunities. We established a new genetic link between COLEC10, TNFRSF11B and JIA/BMD. Additionally, the identification of RHOH underscores its role in positive thymocyte selection, thereby illuminating a critical facet of JIA's underlying biological mechanisms.


Assuntos
Artrite Juvenil , Estudo de Associação Genômica Ampla , Humanos , Artrite Juvenil/genética , Artrite Juvenil/tratamento farmacológico , Predisposição Genética para Doença , Genômica , Fatores Reguladores de Interferon/genética
3.
Phys Chem Chem Phys ; 26(21): 15286-15291, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38757572

RESUMO

A material with the "hidden" negative linear compressibility (NLC) will expand along a specific crystal direction upon uniformly compression to a critical pressure; such materials are thought to be promising candidates for non-linear actuators, switches and sensors. Herein, we use density functional theory (DFT) calculations to uncover the hidden NLC in a V-shaped molecular crystal, bis(5-amino-1,2,4-triazol-3-yl)methane (BATZM). The calculations indicate that the crystal is normally compressed over the pressure range of 0-3 GPa while it expands along the b-axis when the external hydrostatic pressure exceeds 3 GPa. The compressive behavior of the BATZM crystal is modulated by inter-molecular hydrogen bonds, which act as highly compressible springs at low pressures but robust struts at high pressures. Hence, the crystal prefers to compress the hydrogen bonds coupled with PLC at first and flatten the molecules, coupled with later NLC to resist the increasing external pressure. The compressive behavior of BATZM provides a strategy to design more hidden NLC materials via the rational use of the hydrogen bonds.

4.
Phys Chem Chem Phys ; 26(4): 3605-3613, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38214951

RESUMO

High-pressure phase diagrams of the La-N binary system were systematically constructed using the CALYPSO method and first-principles calculations. In addition to the pressure-induced La-N compounds reported previously, we have uncovered a hitherto unknown LaN9 structure in Pm3̄ symmetry stabilized within a narrow pressure range of 20-24.5 GPa. Notably, LaN9 stands as the first thermodynamically stable metal nine-nitrogen compound, featuring centrosymmetric linear N3 anion units and an edge-sharing LaN12 icosahedron. Charge transfer between the La and N atoms plays a crucial role in facilitating structural stability. Furthermore, we identified a novel Cm phase for LaN8, which has a lower enthalpy compared to the previously reported phase. N atoms in Cm LaN8 are polymerized into infinite N∞ chains. Calculations demonstrate the potential recoverability of LaN9 and Cm LaN8 under atmospheric conditions while preserving their initial polynitrogen configuration. From the perspective of detonation pressure and detonation velocity, LaN9 and Cm LaN8 exhibit excellent explosive performance in comparison to TNT and HMX, with estimated energy densities of 0.9 and 1.54 kJ g-1, respectively, indicating their potential utility as high-energy-density materials.

5.
Phys Chem Chem Phys ; 26(7): 6037-6048, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38295373

RESUMO

Porous carbons (PCs) have been widely investigated as electrode materials for supercapacitors. However, during the preparation process, intense pore formation reactions result in an amorphous carbon structure, which limits the rate performance of the electrode material. Herein, coal is chosen as a carbon source and making use of different reaction characteristics of vitrinite and inertinite with a KOH activator, an interconnected porous structure carbon material with an abundant graphite microcrystalline structure is obtained; the organic relationships between the ratio of vitrinite and inertinite, carbonization conditions, material structure and capacity performance were researched. At the ratio of vitrinite to inertinite of 1 : 2, the sample shows a specific surface area of 2507 m2 g-1 and its ID1/IG is 1.31, which is lower than that of raw coal (1.36). Due to the synergistic effect of the pore structure and graphite microcrystals, PC-900-40 exhibits an improved specific capacitance of 229.40 F g-1 at a current density of 1.0 A g-1, and even at a high current density of 10.0 A g-1 it delivers a specific capacitance of 170.04 F g-1. The PC-900-40//PC-900-40 symmetrical capacitor retains 96% of its initial capacitance after 20 000 cycles.

6.
J Chem Phys ; 161(1)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38949593

RESUMO

Inert gases (e.g., He and Xe) can exhibit chemical activity at high pressure, reacting with other substances to form compounds of unexpected chemical stoichiometry. This work combines first-principles calculations and crystal structure predictions to propose four unexpected stable compounds of CH4Xe3, (CH4)2Xe, (CH4)3Xe, and (CH4)3Xe2 at pressure ranges from 2 to 100 GPa. All structures are composed of isolated Xe atoms and CH4 molecules except for (CH4)3Xe2, which comprises a polymerization product, C3H8, and hydrogen molecules. Ab initio molecular dynamics simulations indicate that pressure plays a very important role in the different temperature driving state transitions of CH4-Xe compounds. At lower pressures, the compounds follow the state transition of solid-plastic-fluid phases with increasing temperature, while at higher pressures, the stronger Xe-C interaction induces the emergence of a superionic state for CH4Xe3 and (CH4)3Xe2 as temperature increases. These results not only expand the family of CH4-Xe compounds, they also contribute to models of the structures and evolution of planetary interiors.

7.
Clin Lab ; 70(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39193957

RESUMO

BACKGROUND: As an opportunistic pathogenic fungus, Schizophyllum has been rarely reported to infect humans. By reporting a case of definite diagnosis of Schizophyllum infection, we aim to improve clinicians' understanding of this bacterium. METHODS: By reporting a case with cough and sputum as the main manifestations, after empirical antiinfective chest CT suggesting a more progressive inflammatory lesion and a mass-like lesion in the paratracheal area of the main airways, a diagnosis of Schizophyllum infection was finally made by bronchoscopy with the delivery of metagenomic next-generation sequencing (mNGS). RESULTS: The patient was finally diagnosed with rare Schizophyllum infection. After antifungal treatment, the symptoms improved, and the patient was discharged. CONCLUSIONS: Although Schizophyllum is a rare fungal infection, it should be taken seriously in patients with diabetes or who are immunocompromised. At the same time, mNGS plays a key role in the detection of rare and emerging pathogens, which is worthy of clinical interest.


Assuntos
Antifúngicos , Schizophyllum , Humanos , Schizophyllum/isolamento & purificação , Schizophyllum/genética , Antifúngicos/uso terapêutico , Eosinofilia/diagnóstico , Eosinofilia/microbiologia , Masculino , Broncoscopia , Sequenciamento de Nucleotídeos em Larga Escala , Tomografia Computadorizada por Raios X , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/microbiologia , Pneumopatias Fúngicas/tratamento farmacológico , Pessoa de Meia-Idade , Micoses/diagnóstico , Micoses/microbiologia , Micoses/tratamento farmacológico , Micoses/complicações
8.
Ecotoxicol Environ Saf ; 273: 116163, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38442473

RESUMO

BACKGROUNDS: Short-term exposure to air pollutants increases the risk of migraine, but the long-term impacts of exposure to multiple pollutants on migraine have not been established. The aim of this large prospective cohort study was to explore these links. METHODS: A total of 458,664 participants who were free of migraine at baseline from the UK Biobank were studied. Cox proportional hazards models were used to estimate the risk of new-onset migraine from combined long-term exposure to four pollutants, quantified as an air pollution score using principal component analysis. RESULTS: During a median (IQR) follow-up of 12.5 (11.8, 13.2) years, a total of 5417 new-onset migraine cases were documented. Long-term exposure to multiple air pollutants was associated with an increased risk of new-onset migraine, as indicated by an increased in the SDs of PM2.5 (hazard ratio (HR): 1.04, 95% CI: 1.01-1.06, P = 0.009), PM10 (HR: 1.07, 95% CI: 1.04-1.10, P < 0.001), NO2 (HR: 1.10, 95% CI: 1.07-1.13, P < 0.001) and NOx (HR: 1.04, 95% CI: 1.01-1.07, P = 0.005) in the main model. The air pollution score showed a doseresponse association with an increased risk of new-onset migraine. Similarly, compared with those of the lowest tertile, the HRs (95% CI) of new-onset migraine were 1.11 (95% CI: 1.04-1.19, P = 0.002) and 1.17 (95% CI: 1.09-1.26, P < 0.001) in tertiles 2 and 3, respectively, according to the main model (P trend < 0.001). CONCLUSION: Long-term individual and joint exposure to multiple air pollutants is associated with an increased risk of new-onset migraine.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Humanos , Poluentes Atmosféricos/análise , Material Particulado/toxicidade , Estudos Prospectivos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/efeitos adversos , Dióxido de Nitrogênio
9.
Ren Fail ; 46(1): 2355354, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38785302

RESUMO

Serum magnesium levels exceeding 0.9 mmol/L are associated with increased survival rates in patients with CKD. This retrospective study aimed to identify risk factors for cardio-cerebrovascular events among patients receiving continuous ambulatory peritoneal dialysis (CAPD) and to examine their correlations with serum magnesium levels. Sociodemographic data, clinical physiological and biochemical indexes, and cardio-cerebrovascular event data were collected from 189 patients undergoing CAPD. Risk factors associated with cardio-cerebrovascular events were identified by univariate binary logistic regression analysis. Correlations between the risk factors and serum magnesium levels were determined by correlation analysis. Univariate regression analysis identified age, C-reactive protein (CRP), red cell volume distribution width standard deviation, red cell volume distribution width corpuscular volume, serum albumin, serum potassium, serum sodium, serum chlorine, serum magnesium, and serum uric acid as risk factors for cardio-cerebrovascular events. Among them, serum magnesium ≤0.8 mmol/L had the highest odds ratio (3.996). Multivariate regression analysis revealed that serum magnesium was an independent risk factor, while serum UA (<440 µmol/L) was an independent protective factor for cardio-cerebrovascular events. The incidence of cardio-cerebrovascular events differed significantly among patients with different grades of serum magnesium (χ2 = 12.023, p = 0.002), with the highest incidence observed in patients with a serum magnesium concentration <0.8 mmol/L. High serum magnesium levels were correlated with high levels of serum albumin (r = 0.399, p < 0.001), serum potassium (r = 0.423, p < 0.001), and serum uric acid (r = 0.411, p < 0.001), and low levels of CRP (r = -0.279, p < 0.001). In conclusion, low serum magnesium may predict cardio-cerebrovascular events in patients receiving CAPD.


Assuntos
Magnésio , Diálise Peritoneal Ambulatorial Contínua , Humanos , Masculino , Feminino , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Pessoa de Meia-Idade , Magnésio/sangue , Estudos Retrospectivos , Fatores de Risco , Adulto , Idoso , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Incidência , Transtornos Cerebrovasculares/etiologia , Transtornos Cerebrovasculares/sangue , Transtornos Cerebrovasculares/epidemiologia , Modelos Logísticos , Proteína C-Reativa/análise , Ácido Úrico/sangue , Falência Renal Crônica/terapia , Falência Renal Crônica/sangue
10.
J Asian Nat Prod Res ; 26(4): 510-518, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37705345

RESUMO

Eriocitrin is a flavonoid glycoside with strong antioxidant capacity that has a variety of pharmacological activities, such as hypolipidemic, anticancer and anti-inflammatory effects. We found that the gut microbiota could rapidly metabolize eriocitrin. By using LC/MSn-IT-TOF, we identified three metabolites of eriocitrin metabolized in the intestinal microbiota: eriodictyol-7-O-glucoside, eriodictyol, and dihydrocaffeic acid. By comparing these two metabolic pathways of eriocitrin (the gut microbiota and liver microsomes), the intestinal microbiota may be the primary metabolic site of eriocitrin metabolism. These findings provide a theoretical foundation for the study of pharmacologically active substances.


Assuntos
Flavanonas , Microbioma Gastrointestinal , Antioxidantes/farmacologia , Flavonoides/farmacologia , Biotransformação
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