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1.
Nature ; 596(7871): 301-305, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34321660

RESUMO

Ketamine is a non-competitive channel blocker of N-methyl-D-aspartate (NMDA) receptors1. A single sub-anaesthetic dose of ketamine produces rapid (within hours) and long-lasting antidepressant effects in patients who are resistant to other antidepressants2,3. Ketamine is a racemic mixture of S- and R-ketamine enantiomers, with S-ketamine isomer being the more active antidepressant4. Here we describe the cryo-electron microscope structures of human GluN1-GluN2A and GluN1-GluN2B NMDA receptors in complex with S-ketamine, glycine and glutamate. Both electron density maps uncovered the binding pocket for S-ketamine in the central vestibule between the channel gate and selectivity filter. Molecular dynamics simulation showed that S-ketamine moves between two distinct locations within the binding pocket. Two amino acids-leucine 642 on GluN2A (homologous to leucine 643 on GluN2B) and asparagine 616 on GluN1-were identified as key residues that form hydrophobic and hydrogen-bond interactions with ketamine, and mutations at these residues reduced the potency of ketamine in blocking NMDA receptor channel activity. These findings show structurally how ketamine binds to and acts on human NMDA receptors, and pave the way for the future development of ketamine-based antidepressants.


Assuntos
Microscopia Crioeletrônica , Ketamina/química , Ketamina/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/ultraestrutura , Antidepressivos/química , Antidepressivos/metabolismo , Antidepressivos/farmacologia , Asparagina/química , Asparagina/metabolismo , Sítios de Ligação , Ácido Glutâmico/química , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Glicina/química , Glicina/metabolismo , Glicina/farmacologia , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ketamina/metabolismo , Leucina/química , Leucina/metabolismo , Simulação de Dinâmica Molecular , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/ultraestrutura , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/metabolismo
2.
Nature ; 599(7886): 599-604, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34819685

RESUMO

Amorphous materials inherit short- and medium-range order from the corresponding crystal and thus preserve some of its properties while still exhibiting novel properties1,2. Due to its important applications in technology, amorphous carbon with sp2 or mixed sp2-sp3 hybridization has been explored and prepared3,4, but synthesis of bulk amorphous carbon with sp3 concentration close to 100% remains a challenge. Such materials inherit the short-/medium-range order of diamond and should also inherit its superior properties5. Here, we successfully synthesized millimetre-sized samples-with volumes 103-104 times as large as produced in earlier studies-of transparent, nearly pure sp3 amorphous carbon by heating fullerenes at pressures close to the cage collapse boundary. The material synthesized consists of many randomly oriented clusters with diamond-like short-/medium-range order and possesses the highest hardness (101.9 ± 2.3 GPa), elastic modulus (1,182 ± 40 GPa) and thermal conductivity (26.0 ± 1.3 W m-1 K-1) observed in any known amorphous material. It also exhibits optical bandgaps tunable from 1.85 eV to 2.79 eV. These discoveries contribute to our knowledge about advanced amorphous materials and the synthesis of bulk amorphous materials by high-pressure and high-temperature techniques and may enable new applications for amorphous solids.

3.
Biochem Biophys Res Commun ; 691: 149310, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38039838

RESUMO

In this study, gallium- and gelatin-modified strontium-doped hydroxyapatite (SrHA-Gel-Ga) bilayer coatings were prepared on titanium substrates by electrodeposition and spin-coating techniques. The results showed that gallium and gelatin were uniformly doped into the SrHA coatings, which exhibited good hydrophilicity and bioactivity. Furthermore, SrHA-Gel-Ga demonstrated good antimicrobial properties against E. coli and S. aureus, especially S. aureus. The co-doping of Sr and gelatin in the coatings was effective in mitigating the cytotoxicity of Ga. SrHA-Gel-Ga was better able to promote the adhesion, proliferation and early differentiation of MC3T3-E1 cells. This study provides a new strategy for the development of anti-infective bone repair coatings.


Assuntos
Anti-Infecciosos , Gelatina , Gelatina/farmacologia , Escherichia coli , Staphylococcus aureus , Osteogênese , Anti-Infecciosos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Titânio/farmacologia
4.
Small ; 20(5): e2305762, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37759422

RESUMO

In the search for sustainable cathode materials for aqueous zinc ion batteries (AZIBs), vanadium (V)-based materials have garnered interest, primarily due to their abundance and multiple oxidation states. Among the contenders, Li3 VO4 (LiVO) stands out for its affordability, high specific capacity, and elevated ionic conductivity. However, its limited electrical conductivity results in significant resistance polarization, limiting its rate capability, especially under high currents. Through density functional theory (DFT) calculations, this study evaluates the electrochemical implications of carbon (C) incorporation within the LiVO matrix. The findings indicate that C integration significantly ameliorates the conductivity of LiVO. Moreover, C serves as a barrier, mitigating direct interactions between Zn2+ and LiVO, which in turn expedites Zn2+ diffusion. When considering various C materials for this role, glucose is emerged as the optimal candidate. The LiVO/C-glucose composite (LiVO/C-G) is observed to undergo dual phase transitions during charge-discharge cycles, resulting in an amorphous vanadium-oxygen (VO) derivative, paving the way for subsequent electrochemical reactions. Collectively, the insights pave a promising avenue for refining AZIB cathode design and performance.

5.
Langmuir ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042028

RESUMO

Mixed potential ammonia (NH3) sensors with the Fe- and Mo-codoped BiVO4 sensing electrode and Ag reference electrode based on the yttria-stabilized zirconia solid electrolyte were developed. Fe- and Mo-doped BiVO4 sensing materials were prepared using solution combustion synthesis and then characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). It was observed that Fe doping could greatly improve the response rate, while Mo doping could enhance the response signal (ΔU) and sensitivity. Based on the optimal doping ratio of Fe and Mo each, the synergistic enhancement of the performance by Fe and Mo codoping was investigated. The sensor coated by BiV0.75Fe0.2Mo0.05Oδ materials exhibited a prominent sensing performance to a low concentration of 10-50 ppm of NH3 at 525 °C with the outstanding sensitivity of -148.988 mV/decade. Fe and Mo doping also improved the selectivity of the sensor to NH3, with the relative deviations less than ±8% of other typical gases' interference including NO, NO2, CO, CO2, and CH4. Besides, the sensor showed good resistance to fluctuations in the oxygen concentration and favorable stability against changes in the water vapor concentration. In addition, the sensor also exhibited good long-term stability. The mixed potential response mechanism was further discussed and analyzed through polarization curves as well as through gas chromatography and infrared absorption spectroscopy.

6.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 174-181, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38650145

RESUMO

Ovarian cancer is a prevalent malignancy in the female reproductive system, representing a significantly fatal and incurable tumor. Chelerythrine (CHE), a natural benzopyridine alkaloid, has demonstrated a broad spectrum of anticancer activities. Nevertheless, the ovarian cancer inhibitory impact of CHE remains unclear. In this study, we investigated the cytotoxic mechanism and potential targets of CHE on in vitro cultures of A2780 and SKOV3 cells derived from ovarian cancer. Additionally, in vivo experiments were conducted to confirm the suppressive impact of CHE on tumor growth in nude mice. The findings revealed that CHE impeded the growth of A2780 and SKOV3 cells in a concentration-time-dependent manner and significantly suppressed the development of tumors in nude mice. CHE elevated the level of oxidative stress in tumor cells, prompted cell cycle halt in the S phase, and increased their mitochondrial membrane potential. Western blotting results demonstrated that CHE could modulate the expression of proteins associated with apoptotic and ferroptosis processes in A2780 and SKOV3 cells. Nrf2 was verified to be an upstream key target mediating the inhibitory impact of CHE on ovarian cancer cells. In summary, CHE exerts its anti-cancer effects on ovarian cancer by modulating Nrf2, inhibiting cellular proliferation, and promoting apoptosis and ferroptosis.


Assuntos
Apoptose , Benzofenantridinas , Proliferação de Células , Ferroptose , Camundongos Nus , Fator 2 Relacionado a NF-E2 , Neoplasias Ovarianas , Feminino , Benzofenantridinas/farmacologia , Humanos , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Linhagem Celular Tumoral , Ferroptose/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
7.
Molecules ; 29(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38930899

RESUMO

This study explores the enhancement of aqueous zinc-ion batteries (AZIBs) using ammonium-enhanced vanadium oxide cathodes. Density Functional Theory (DFT) calculations reveal that NH4+ incorporation into V6O16 lattices significantly facilitates Zn2+ ion diffusion by reducing electrostatic interactions, acting as a structural lubricant. Subsequent experimental validation using (NH4)2V6O16 cathodes synthesized via a hydrothermal method corroborates the DFT findings, demonstrating remarkable electrochemical stability with a capacity retention of 90% after 2000 cycles at 5 A g-1. These results underscore the potential of NH4+ in improving the performance and longevity of AZIBs, providing a pathway for sustainable energy storage solutions.

8.
Molecules ; 29(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38257230

RESUMO

Hazel leaf, a by-product of hazelnuts, is commonly used in traditional folk medicine in Portugal, Sweden, Iran and other regions for properties such as vascular protection, anti-bleeding, anti-edema, anti-infection, and pain relief. Based on our previous studies, the polyphenol extract from hazel leaf was identified and quantified via HPLC fingerprint. The contents of nine compounds including kaempferol, chlorogenic acid, myricetin, caffeic acid, p-coumaric acid, resveratrol, luteolin, gallic acid and ellagic acid in hazel leaf polyphenol extract (ZP) were preliminary calculated, among which kaempferol was the highest with 221.99 mg/g, followed by chlorogenic acid with 8.23 mg/g. The inhibition of ZP on α-glucosidase and xanthine oxidase activities was determined via the chemical method, and the inhibition on xanthine oxidase was better. Then, the effect of ZP on hyperuricemia zebrafish was investigated. It was found that ZP obviously reduced the levels of uric acid, xanthine oxidase, urea nitrogen and creatinine, and up-regulated the expression ofOAT1 and HPRT genes in hyperuricemia zebrafish. Finally, the targeted network pharmacological analysis and molecular docking of nine polyphenol compounds were performed to search for relevant mechanisms for alleviating hyperuricemia. These results will provide a valuable basis for the development and application of hazel leaf polyphenols as functional ingredients.


Assuntos
Corylus , Hiperuricemia , Animais , Polifenóis/farmacologia , Ácido Clorogênico/farmacologia , Simulação de Acoplamento Molecular , Peixe-Zebra , Farmacologia em Rede , Quempferóis , Hiperuricemia/tratamento farmacológico , Xantina Oxidase , Extratos Vegetais/farmacologia
9.
Molecules ; 29(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38675549

RESUMO

Derived from hazelnuts, hazel leaf has been utilized in traditional folk medicine for centuries in countries such as Portugal, Sweden, and Iran. In our previous investigations, we conducted a preliminary assessment of the hazel leaf polyphenol extract (referred to as ZP) and identified nine compounds, such as kaempferol and chlorogenic acid, in its composition. ZP has shown promising properties as an antioxidant and anti-inflammatory agent. Our research has revealed that ZP has protective effects against cisplatin-induced acute kidney injury (AKI). We conducted a comprehensive examination of both the pathological and ultrastructural aspects and found that ZP effectively ameliorated renal tissue lesions and mitigated mitochondrial damage. Moreover, ZP significantly suppressed malondialdehyde levels while increasing glutathione and catalase concentrations in the kidneys of AKI-induced mice. ZP decreased the number of apoptotic cells and decreased pro-apoptotic protein expression in the kidneys of mice and human renal tubular epithelial cells (HK-2). Furthermore, treatment with ZP increased the levels of proteins marking anti-ferroptosis, such as GPX4, FTH1, and FSP1, in experiments both in vivo and in vitro. We elucidated the underlying mechanisms of ZP's actions, revealing its inhibitory effect on Yap phosphorylation and its regulation of Lats expression, which exert a protective influence on the kidneys. Furthermore, we found that inhibiting the Hippo pathway compromised ZP's nephroprotective effects in both in vitro and in vivo studies. In summary, this research shows that ZP exhibits renoprotective properties, effectively reducing oxidative damage, apoptosis, and ferroptosis in the kidneys by targeting the Hippo pathway.


Assuntos
Injúria Renal Aguda , Cisplatino , Ferroptose , Via de Sinalização Hippo , Extratos Vegetais , Folhas de Planta , Polifenóis , Transdução de Sinais , Animais , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/induzido quimicamente , Ferroptose/efeitos dos fármacos , Cisplatino/efeitos adversos , Polifenóis/farmacologia , Polifenóis/química , Camundongos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Humanos , Transdução de Sinais/efeitos dos fármacos , Folhas de Planta/química , Proteínas Serina-Treonina Quinases/metabolismo , Masculino , Linhagem Celular , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Estresse Oxidativo/efeitos dos fármacos
10.
Small ; 19(39): e2301870, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37236170

RESUMO

Aqueous zinc ion batteries (AZIBs) have attracted attention as a promising candidate for secondary battery energy storage due to their safety and environmental benefits. However, the vanadium-based cathode material NH4 V4 O10 has the problem of structural instability. In this paper, it is found by density functional theory calculation that excessive NH4 + located in the interlayer will repel the Zn2+ during the process of Zn2+ insertion. This results in the distortion of the layered structure, further affects the diffusion of Zn2+ and reduces the reaction kinetics. Therefore, part of the NH4 + is removed by heat treatment. In addition, the introduction of Al3+ into the material by hydrothermal method is able to further enhance its zinc storage properties. This dual-engineering strategy shows excellent electrochemical performance (578.2 mAh g-1 at 0.2 A g-1 ). This study provides valuable insights for the development of high performance AZIBs cathode materials.

11.
Small ; 19(50): e2304668, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37626454

RESUMO

The inherent slow diffusion dynamics of aqueous zinc-ion batteries (AZIBs) act as a significant hindrance to their universal utilization as energy storage systems, largely attributed to the scarcity of superior cathode materials. In this study, a novel method that amalgamates oxygen defect engineering and polymer intercalation, guided by theoretical computations, to confront this challenge, is introduced. This approach begins with density functional theory calculations, demonstrating that the shielding effect rendered by polypyrrole (PPy) between NH4 V3 O8 (NVO) layers, along with the cooperative influence of oxygen defects (Od ), optimizes the kinetic transport of Zn2+ . Leveraging these theoretical outcomes, a two-step hydrothermal synthesis procedure is devised to fabricate PPy-intercalated NVO embedded with Od (NVO-Od @PPy). The empirical findings corroborate the theoretical predictions, showcasing that the NVO-Od @PPy//Zn system manifests exceptional cycling stability. Specifically, the NVO-Od @PPy electrode delivers an optimal reversible capacity, yielding 421 mAh g-1 at a current density of 0.1 A g-1 . Remarkably, even at an elevated current density of 10 A g-1 , it sustains a capacity of 175.7 mAh g-1 , while maintaining a capacity retention of 99% over 1000 cycles. This research provides pivotal insights for the engineering of high-performing cathode materials for AZIBs, paving the way for their future advancements.

12.
Opt Express ; 31(9): 14785-14795, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157335

RESUMO

In this paper, we demonstrated a miniaturized diffractive/refractive hybrid system based on a diffractive optical element and three refractive lenses to achieve solar-blind ultraviolet imaging within a range of 240-280 nm. We experimentally demonstrate the optical system has both outstanding resolution and excellent imaging capability. The experiments demonstrate that the system could distinguish the smallest line pair with a width of 16.7 µm. The modulation transfer function (MTF) at the target maximum frequency (77 lines pair/mm) is great than 0.76. The strategy provides significant guidance for the mass production of solar-blind ultraviolet imaging systems towards miniaturization and lightweight.

13.
Ann Hematol ; 102(12): 3335-3343, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37922006

RESUMO

Erdheim-Chester disease (ECD) is a rare and probably fatal multisystemic non-Langerhans cell histiocytosis (LCH). To comprehensively investigate the clinical features, genomic analysis, treatments, and prognostic factors of ECD, we retrospectively analyzed the clinical data of 75 ECD patients and 10 mixed LCH and ECD patients in our center. The median age at diagnosis was 46 years (range, 5-70). ECD patients were older at diagnosis (p = 0.006) and had more cardiac involvement (p = 0.011) as well as vascular (p = 0.031) involvement compared to mixed LCH and ECD patients. 64.8% of ECD patients and 87.5% of mixed LCH and ECD patients carried BRAFV600E mutation. The BRAFV600E mutation correlated with a greater number of affected organs (p = 0.030) and was associated with lung involvement (p = 0.033) as well as pleural involvement (p = 0.002). The median follow-up time was 38 months (range, 1-174). The estimated 5-year progression-free survival (PFS) and overall survival (OS) were 48.9% and 84.7%, respectively. In a multivariate analysis, right atrial pseudotumor (p = 0.013) and pancreatic involvement (p = 0.005) predicted worse OS, while pleural (p = 0.042) and central nervous system (CNS) involvement (p = 0.043) predicted worse PFS. Our study described the clinical spectrum of ECD and mixed LCH and ECD, while also revealed the prognostic value of right atrial pseudotumor and pancreatic, pleural, and CNS involvement for worse survival.


Assuntos
Fibrilação Atrial , Doença de Erdheim-Chester , Histiocitose de Células de Langerhans , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Doença de Erdheim-Chester/genética , Doença de Erdheim-Chester/complicações , Prognóstico , Estudos Retrospectivos , Proteínas Proto-Oncogênicas B-raf/genética , Fibrilação Atrial/complicações , Histiocitose de Células de Langerhans/patologia
14.
Clin Exp Rheumatol ; 41(5): 1068-1076, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36226610

RESUMO

OBJECTIVES: Systemic lupus erythematosus (SLE) is an autoimmune disease characterised by immune inflammation. It involves multiple organs. Many studies have demonstrated that circRNAs are closely associated with SLE. Nonetheless, the potential mechanism by which circRNAs impacts SLE is not fully understood. The aim of this study was to explore the regulatory roles of circRNAs, the key genes and pathways governing the pathophysiological processes of SLE, and to screen therapeutic agents. METHODS: The sequencing data of circRNA, miRNA and mRNA were obtained from Gene Expression Omnibus (GEO) datasets. Candidates were identified to construct a circRNA-miRNA-mRNA network based on circRNA-miRNA interactions and miRNA-mRNA interactions. Gene functional enrichments were performed on the DAVID database. Protein-protein interaction (PPI) network was constructed by STRING database and visualised in Cytoscape software. The hub genes were explored by the MCODE plugin app. The Connectivity Map L1000 platform was used to identify potential agents. RESULTS: A total of 1093 differentially expressed circRNAs (DEcircRNAs), 42 differentially expressed miRNAs (DEmiRNAs) and 1431 differentially expressed mRNAs (DEmRNAs) were identified. We integrated 3 overlapped circRNAs, 13 miRNAs and 352 target mRNAs into a circRNA-miRNA-mRNA network. We next identified 44 hub genes based on the PPI network. KEGG pathway analysis revealed that the DEGs were mainly associated with MAPK signalling pathway. In addition, we discovered several chemicals as potential treatment options for SLE. CONCLUSIONS: Through this bioinformatics analysis, we suggest a regulatory role for circRNAs in the pathogenesis and treatment of SLE from the view of a competitive endogenous RNA (ceRNA) network.


Assuntos
Lúpus Eritematoso Sistêmico , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Mapas de Interação de Proteínas/genética , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/genética , Redes Reguladoras de Genes
15.
Angew Chem Int Ed Engl ; 62(13): e202218666, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36723272

RESUMO

The fictive temperature (Tf ) is widely applied to understand the relaxation thermodynamics of a glass; however, its atomic structural origin is still unclear. Here, we report two novel AZnP3 O9 glasses obtained by melting the composition identical single crystals. These glasses exhibit structural inheritance within 5 Šfrom the single crystal counterparts that is quantified by δ=nglass /ncry (0≤δ≤1, n is the number of pair correlation functions). Among the available glass-formers, glass KZnP3 O9 exhibits the highest structural inheritance (δ=1, nglass =8). More insightfully, a reverse correlation between δ and the relaxation thermodynamic parameters is observed in glass AZnP3 O9 , revealing for the first time the atomic structural origin of fictive temperature.

16.
Small ; 18(47): e2204180, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36228084

RESUMO

Aqueous zinc ion batteries are a promising alternative secondary battery technology due to their excellent safety and environmental friendliness. Vanadium-based compounds as a highly promising class of cathode materials still suffer from structural collapse and slow kinetics. Studies have shown that metal ion pre-introduction is an effective method to solve these problems and enhance battery performance. Here, the introduction of Al3+ , Cr3+ , Cu2+ and Fe3+ is found to effectively reduce the migration energy barrier of Zn2+ with the density functional theory calculations, while Al3+ exhibits the best induction effects. Subsequently, Al0.34 V5 O12 ·2.4H2 O (AlVOH) nanoribbons are synthesized by hydrothermal introduction of Al3+ , demonstratin excellent electrochemical properties (407.8 mAh g-1 at 0.2 A g-1 and 176.3 mAh g-1 after 2000 cycles at 20 A g-1 ). By further compounding with redox graphene (rGO), AlVOH/rGO exhibits high capacitance and specific capacity (460.4 mAh g-1 at 0.2 A g-1 and 180.6 mAh g-1 after 2000 cycles at 20 A g-1 ). In addition, it is found that the introduction of metal ions adjusts the structural water content of the material. Especially, the introduction of Al3+ can increase the interlayer structural water content and make the electrochemical properties of the material more stable.

17.
Opt Express ; 30(2): 2402-2412, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209381

RESUMO

The nano-focusing performance of adiabatically designed Cartesian oval refocusing lenses is compared with other well known compound refractive lenses with parabolic profiles (both simple concave and kinoform types). Using beam propagation method (BPM) simulation, it is shown that our design based on oval lenses does significantly improve the focusing properties compared to other parabolic lens based designs, e.g. adiabatically focusing lenses (AFLs), which doesn't take into account of the refocusing effect. This points to the importance of optimizing complex lens design in improving nano-focusing lens performance.

18.
Langmuir ; 38(50): 15506-15515, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36480753

RESUMO

In this study, the flame spray pyrolysis (FSP) technique was employed to produce WO3 nanoparticles, which were subsequently used as sensing materials for NO2 sensors. To enhance the sensing performance, the effects of flame parameters on the particle properties and sensing performances for 150-1200 ppb NO2 at 125 °C were investigated. The results indicate that WO3 particles with an average crystal size of about 10-20 nm and a standard deviation of about 3-7.5 nm were generated by controlling the precursor and dispersion oxygen flow rate of FSP. Based on the evaluation of NO2 sensing performance, WO3 sensing materials synthesized under the 3/5 flame condition exhibited better sensitivity than sensors made under other flame conditions. In summary, the FSP method and the optimization of flame synthesis parameters could be an effective strategy to prepare the sensing materials with high sensing performance.

20.
Clin Lab ; 68(7)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35975517

RESUMO

BACKGROUND: To investigate the CT imaging features and microbial phenotypes of primary severe community-acquired pneumonia caused by hypervirulent Klebsiella pneumoniae (hvKp). METHODS: Patients diagnosed with primary hvKp pneumonia were included, and their clinical data were analyzed, including the baseline characteristics and CT imaging results. After hypermucoviscosity phenotyping, the strains, serological types, and virulence genes of hvKp were identified using multiplex PCR. RESULTS: Twelve patients with primary hvKp pneumonia were included (11 males, 1 female). All patients were infected via respiratory tract inhalation. Ten patients were long-term drinkers. Four patients (33.3%), who were long-term alcohol abusers, died within 30 days after diagnosis. No extrapulmonary metastatic infection was found in any patient. The imaging of lung lesions at the early disease stage exhibited an extensive consolidation in the lungs. As the disease progressed, the most common imaging features were pleural effusion (9/12), cavitation and necrosis (8/12), and pneumothorax (3/12). The serological typing of the capsular polysaccharides on hvKp strains were K1 (6/12) and K2 (6/12). Furthermore, the virulence genotyping showed rmpA (11/12), magA (11/12), ureA (12/12), mrkD (12/12), fim-1 (12/12), wabG (12/12), ybtS (12/12), and iucB (11/12). CONCLUSIONS: Primary severe community-acquired hvKp-associated pneumonia is more common in men, especially those with a long-term history of alcohol consumption. CT scanning at the early disease stage mostly showed extensive pulmonary consolidation, which was prone to be combined with cavitation, necrosis, and pleural effusion. K1 and K2 serotypes were identified among the hvKp strains, which were not prone to form extrapulmonary metastasis via the bloodstream.


Assuntos
Infecções Comunitárias Adquiridas , Infecções por Klebsiella , Derrame Pleural , Pneumonia , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/diagnóstico por imagem , Infecções Comunitárias Adquiridas/tratamento farmacológico , Feminino , Humanos , Infecções por Klebsiella/diagnóstico , Klebsiella pneumoniae/genética , Masculino , Tipagem de Sequências Multilocus , Necrose/tratamento farmacológico , Pneumonia/tratamento farmacológico
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