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1.
Neuroradiology ; 66(10): 1681-1691, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38985319

RESUMO

PURPOSE: To develop thrombus radiomics models based on dual-energy CT (DECT) for predicting etiologic cause of stroke. METHODS: We retrospectively enrolled patients with occlusion of the middle cerebral artery who underwent computed tomography (NCCT) and DECT angiography (DECTA). 70 keV virtual monoenergetic images (simulate conventional 120kVp CTA images) and iodine overlay maps (IOM) were reconstructed for analysis. Five logistic regression radiomics models for predicting cardioembolism (CE) were built based on the features extracted from NCCT, CTA and IOM images. From these, the best one was selected to integrate with clinical information for further construction of the combined model. The performance of the different models was evaluated and compared using ROC curve analysis, clinical decision curves (DCA), calibration curves and Delong test. RESULTS: Among all the radiomic models, model NCCT+IOM performed the best, with AUC = 0.95 significantly higher than model NCCT, model CTA, model IOM and model NCCT+CTA in the training set (AUC = 0.88, 0.78, 0.90,0.87, respectively, P < 0.05), and AUC = 0.92 in the testing set, significantly higher than model CTA (AUC = 0.71, P < 0.05). Smoking and NIHSS score were independent predictors of CE (P < 0.05). The combined model performed similarly to the model NCCT+IOM, with no statistically significant difference in AUC either in the training or test sets. (0.96 vs. 0.95; 0.94 vs. 0.92, both P > 0.05). CONCLUSION: Radiomics models constructed based on NCCT and IOM images can effectively determine the source of thrombus in stroke without relying on clinical information.


Assuntos
Angiografia por Tomografia Computadorizada , Infarto da Artéria Cerebral Média , Humanos , Masculino , Feminino , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Estudos Retrospectivos , Pessoa de Meia-Idade , Angiografia por Tomografia Computadorizada/métodos , Idoso , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Angiografia Cerebral/métodos , Trombose/diagnóstico por imagem , Trombose/complicações , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Meios de Contraste , Radiômica
2.
Angew Chem Int Ed Engl ; 63(23): e202403245, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38578838

RESUMO

The encapsulation of functional colloidal nanoparticles (100 nm) into single-crystalline ZSM-5 zeolites, aiming to create uniform core-shell structures, is a highly sought-after yet formidable objective due to significant lattice mismatch and distinct crystallization properties. In this study, we demonstrate the fabrication of a core-shell structured single-crystal zeolite encompassing an Fe3O4 colloidal core via a novel confinement stepwise crystallization methodology. By engineering a confined nanocavity, anchoring nucleation sites, and executing stepwise crystallization, we have successfully encapsulated colloidal nanoparticles (CN) within single-crystal zeolites. These grafted sites, alongside the controlled crystallization process, compel the zeolite seed to nucleate and expand along the Fe3O4 colloidal nanoparticle surface, within a meticulously defined volume (1.5×107≤V≤1.3×108 nm3). Our strategy exhibits versatility and adaptability to an array of zeolites, including but not restricted to ZSM-5, NaA, ZSM-11, and TS-1 with polycrystalline zeolite shell. We highlight the uniformly structured magnetic-nucleus single-crystalline zeolite, which displays pronounced superparamagnetism (14 emu/g) and robust acidity (~0.83 mmol/g). This innovative material has been effectively utilized in a magnetically stabilized bed (MSB) reactor for the dehydration of ethanol, delivering an exceptional conversion rate (98 %), supreme ethylene selectivity (98 %), and superior catalytic endurance (in excess of 100 hours).

3.
J Am Chem Soc ; 144(9): 3892-3901, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35191672

RESUMO

As one of the most important parameters of the nanomotors' motion, precise speed control of enzyme-based nanomotors is highly desirable in many bioapplications. However, owing to the stable physiological environment, it is still very difficult to in situ manipulate the motion of the enzyme-based nanomotors. Herein, inspired by the brakes on vehicles, the near-infrared (NIR) "optical brakes" are introduced in the glucose-driven enzyme-based mesoporous nanomotors to realize remote speed regulation for the first time. The novel nanomotors are rationally designed and fabricated based on the Janus mesoporous nanostructure, which consists of the SiO2@Au core@shell nanospheres and the enzymes-modified periodic mesoporous organosilicas (PMOs). The nanomotor can be driven by the biofuel of glucose under the catalysis of enzymes (glucose oxidase/catalase) on the PMO domain. Meanwhile, the Au nanoshell at the SiO2@Au domain enables the generation of the local thermal gradient under the NIR light irradiation, driving the nanomotor by thermophoresis. Taking advantage of the unique Janus nanostructure, the directions of the driving force induced by enzyme catalysis and the thermophoretic force induced by NIR photothermal effect are opposite. Therefore, with the NIR optical speed regulators, the glucose-driven nanomotors can achieve remote speed manipulation from 3.46 to 6.49 µm/s (9.9-18.5 body-length/s) at the fixed glucose concentration, even after covering with a biological tissue. As a proof of concept, the cellar uptake of the such mesoporous nanomotors can be remotely regulated (57.5-109 µg/mg), which offers great potential for designing smart active drug delivery systems based on the mesoporous frameworks of this novel nanomotor.


Assuntos
Nanoestruturas , Dióxido de Silício , Sistemas de Liberação de Medicamentos , Glucose , Glucose Oxidase , Nanoestruturas/química , Dióxido de Silício/química
4.
Nano Lett ; 21(14): 6071-6079, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34269590

RESUMO

Streamlined architectures with a low fluid-resistance coefficient have been receiving great attention in various fields. However, it is still a great challenge to synthesize streamlined architecture with tunable surface curvature at the nanoscale. Herein, we report a facile interfacial dynamic migration strategy for the synthesis of streamlined mesoporous nanotadpoles with varied architectures. These tadpole-like nanoparticles possess a big streamlined head and a slender tail, which exhibit large inner cavities (75-170 nm), high surface areas (424-488 m2 g-1), and uniform mesopore sizes (2.4-3.2 nm). The head curvature of the streamlined mesoporous nanoparticles can be well-tuned from ∼2.96 × 10-2 to ∼5.56 × 10-2 nm-1, and the tail length can also be regulated from ∼30 to ∼650 nm. By selectively loading the Fe3O4 catalyst in the cavity of the streamlined silica nanotadpoles, the H2O2-driven mesoporous nanomotors were designed. The mesoporous nanomotors with optimized structural parameters exhibit outstanding directionality and a diffusion coefficient of 8.15 µm2 s-1.


Assuntos
Nanopartículas , Dióxido de Silício , Catálise , Peróxido de Hidrogênio , Porosidade
5.
Angew Chem Int Ed Engl ; 61(43): e202211307, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36037030

RESUMO

A sulfhydryl monomicelles interfacial assembly strategy is presented for the synthesis of fully exposed single-atom-layer Pt clusters on 2D mesoporous TiO2 (SAL-Pt@mTiO2 ) nanosheets. This synthesis features the introduction of the sulfhydryl group in monomicelles to finely realize the controllable co-assembly process of Pt precursors within ordered mesostructures. The resultant SAL-Pt@mTiO2 shows uniform SAL Pt clusters (≈1.2 nm) anchored in ultrathin 2D nanosheets (≈7 nm) with a high surface area (139 m2 g-1 ), a large pore size (≈25 nm) and a high dispersion (≈99 %). Moreover, this strategy is universal for the synthesis of other SAL metal clusters (Pd and Au) on 2D mTiO2 with high exposure and accessibility. When used as a catalyst for hydrogenation of 4-nitrostyrene, the SAL-Pt@mTiO2 shows a high catalytic activity (TOF up to 2424 h-1 ), 100 % selectivity for 4-aminostyrene, good stability, and anti-resistance to thiourea poisoning under relatively mild conditions (25 °C, 10 bar).

6.
J Dairy Sci ; 102(1): 223-235, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30343912

RESUMO

Lactobacillus helveticus H9 is a probiotic bacterium originating from traditional Tibetan kurut. It has high angiotensin-converting enzyme-inhibitory (ACEI) and antihypertensive activities. We aimed to evaluate the effects of L. helveticus H9 supplementation in yogurt fermentation and storage. We monitored changes of multiple parameters over 28 d of storage at 4°C; namely, pH, titratable acidity, free amino groups, ACEI activity, physical properties, volatile flavor compounds, and sensory quality. Supplementation of L. helveticus H9 enhanced fermented milk acidification and proteolysis, resulting in a shorter fermentation time. The H9 treatment significantly increased the ACEI activity of the fermented milks. Fifteen key volatile flavors were detected by solid-phase microextraction-gas chromatography-mass spectrometry across all samples. More alcohols, aldehydes, and nitrogenous compounds, especially acetoin and benzaldehyde, were detected in the H9-supplemented fermented milks. The human sensory scores for flavor and texture, but not appearance, were lower for the H9-supplemented fermented milks, particularly beyond 2 wk of cold storage. Our results will be of interest to the dairy industry for developing novel functional dairy products.


Assuntos
Lactobacillus helveticus/metabolismo , Iogurte/microbiologia , Animais , Bovinos , Fermentação , Armazenamento de Alimentos , Humanos , Leite/química , Leite/microbiologia , Probióticos/análise , Paladar , Iogurte/análise
7.
Anticancer Drugs ; 28(9): 967-976, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28692436

RESUMO

Lung cancer is the most common cause of cancer-related death worldwide and the platinum-based drugs such as cisplatin have been used as the first line of the treatment. However, the clinical effectiveness of such chemotherapy is limited by intrinsic or acquired resistance. In this study, we found that cisplatin induced autophagy that attenuated the sensitivity of both A549 and Lewis lung cancer (LLC) cells to cisplatin. In contrast, the clinical drug andrographolide (Andro) suppressed autophagy and enhanced cisplatin-mediated apoptosis in these cells. Using two murine lung cancer models, including a subcutaneously inoculated LLC model and an orthotopic LLC implantation model, we investigated the therapeutic efficacy of the combined treatment of cisplatin and Andro. Compared with the sole cisplatin treatment, combining cisplatin with Andro potentially inhibited tumor growth, reduced the incidence of lung metastases, and relieved renal tubular damage. Moreover, the combined treatment prolonged the life span of tumor-bearing mice. TUNEL and immunohistochemistry assays showed the increase in apoptotic cells and the decrease in both conversion of LC3B-I to LC3B-II and Atg5 protein expression in the tumor tissues from mice with the combined treatment. These results suggest that Andro offers an ideal candidate of autophagy inhibitors in clinical application, and combination of cisplatin with Andro could be a promising strategy for the treatment of lung cancer.


Assuntos
Carcinoma Pulmonar de Lewis/tratamento farmacológico , Cisplatino/farmacologia , Diterpenos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Células A549 , Animais , Autofagia/efeitos dos fármacos , Carcinoma Pulmonar de Lewis/patologia , Cisplatino/administração & dosagem , Diterpenos/administração & dosagem , Sinergismo Farmacológico , Feminino , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos C57BL
8.
J Dairy Sci ; 100(12): 9495-9507, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28964517

RESUMO

Our study assayed angiotensin-converting enzyme (ACE) inhibitory activity and fermentation characteristics of 41 food-originated Lactobacillus casei strains in fermented milk production. Twenty-two of the tested strains produced fermented milks with a high ACE inhibitory activity of over 60%. Two strains (IMAU10408 and IMAU20411) expressing the highest ACE inhibitory activity were selected for further characterization. The heat stability (pasteurization at 63°C for 30 min, 75°C for 25 s, and 85°C for 20 s) and resistance to gastrointestinal proteases (pepsin, trypsinase, and sequential pepsin/trypsinase treatments) of the ACE inhibitory activity in the fermented milks produced with IMAU10408 and IMAU20411 were determined. Interestingly, such activity increased significantly after the heat or protease treatment. Because of the shorter milk coagulation time of L. casei IMAU20411 (vs. IMAU10408), it was selected for optimization experiments for ACE inhibitory activity production. Our results show that fermentation temperature of 37°C, inoculum density of 1 × 106 cfu/g, and fermentation time of 12 h were optimal for maximizing ACE inhibitory activity. Finally, the metabolite profiles of L. casei IMAU20411 after 2 and 42 h of milk fermentation were analyzed by ultra-HPLC electron spray ionization coupled with time-of-flight mass spectrometry. Nine differential abundant metabolites were identified, and 2 of them showed a strong and positive correlation with fermented milk ACE inhibitory activity. To conclude, we have identified a novel ACE inhibitory L. casei strain, which has potential for use as a probiotic in fermented milk production.


Assuntos
Fermentação , Lacticaseibacillus casei/metabolismo , Leite/química , Inibidores da Enzima Conversora de Angiotensina/análise , Animais , Reatores Biológicos , Cromatografia Líquida de Alta Pressão , Produtos Fermentados do Leite/análise , Temperatura Alta , Leite/microbiologia , Proteínas do Leite/química , Pasteurização , Peptídeos/análise , Peptídeos/farmacologia , Probióticos/metabolismo
9.
Ann Bot ; 115(2): 303-13, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25564468

RESUMO

BACKGROUND AND AIMS: Empirical studies and allometric partitioning (AP) theory indicate that plant above-ground biomass (MA) scales, on average, one-to-one (isometrically) with below-ground biomass (MR) at the level of individual trees and at the level of entire forest communities. However, the ability of the AP theory to predict the biomass allocation patterns of understorey plants has not been established because most previous empirical tests have focused on canopy tree species or very large shrubs. METHODS: In order to test the AP theory further, 1586 understorey sub-tropical forest plants from 30 sites in south-east China were harvested and examined. The numerical values of the scaling exponents and normalization constants (i.e. slopes and y-intercepts, respectively) of log-log linear MA vs. MR relationships were determined for all individual plants, for each site, across the entire data set, and for data sorted into a total of 19 sub-sets of forest types and successional stages. Similar comparisons of MA/MR were also made. KEY RESULTS: The data revealed that the mean MA/MR of understorey plants was 2·44 and 1·57 across all 1586 plants and for all communities, respectively, and MA scaled nearly isometrically with respect to MR, with scaling exponents of 1·01 for all individual plants and 0·99 for all communities. The scaling exponents did not differ significantly among different forest types or successional stages, but the normalization constants did, and were positively correlated with MA/MR and negatively correlated with scaling exponents across all 1586 plants. CONCLUSIONS: The results support the AP theory's prediction that MA scales nearly one-to-one with MR (i.e. MA ∝ MR (≈1·0)) and that plant biomass partitioning for individual plants and at the community level share a strikingly similar pattern, at least for the understorey plants examined in this study. Furthermore, variation in environmental conditions appears to affect the numerical values of normalization constants, but not the scaling exponents of the MA vs. MR relationship. This feature of the results suggests that plant size is the primary driver of the MA vs. MR biomass allocation pattern for understorey plants in sub-tropical forests.


Assuntos
Biomassa , Florestas , Modelos Biológicos , Árvores/fisiologia , China , Luz , Fotossíntese , Clima Tropical
11.
ACS Nano ; 18(34): 22829-22854, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39152943

RESUMO

Porous materials, characterized by their controllable pore size, high specific surface area, and controlled space functionality, have become cross-scale structures with microenvironment effects and multiple functions and have gained tremendous attention in the fields of catalysis, energy storage, and biomedicine. They have evolved from initial nanopores to multiscale pore-cavity designs with yolk-shell, multishells, or asymmetric structures, such as bottle-shaped, multichambered, and branching architectures. Various synthesis strategies have been developed for the interfacial engineering of porous structures, including bottom-up approaches by using liquid-liquid or liquid-solid interfaces "templating" and top-down approaches toward chemical tailoring of polymers with different cross-linking degrees, as well as interface transformation using the Oswald ripening, Kirkendall effect, or atomic diffusion and rearrangement methods. These techniques permit the design of functional porous materials with diverse microenvironment effects, such as the pore size effect, pore enrichment effect, pore isolation and synergistic effect, and pore local field enhancement effect, for enhanced applications. In this review, we delve into the bottom-up and top-down interfacial-oriented synthesis approaches of porous structures with advanced structures and microenvironment effects. We also discuss the recent progress in the applications of these collaborative effects and structure-activity relationships in the areas of catalysis, energy storage, electrochemical conversion, and biomedicine. Finally, we outline the persisting obstacles and prospective avenues in terms of controlled synthesis and functionalization of porous engineering. The perspectives proposed in this paper may contribute to promote wider applications in various interdisciplinary fields within the confined dimensions of porous structures.

12.
Nat Rev Chem ; 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39443751

RESUMO

Porous nanoreactors mimic the structures and functions of cells, providing an adaptable material with multiple functions and effects. These reactors can be nanoscale containers and shuttles or catalytic centres, drawing in reactants for cascading reactions with multishelled designs. The detailed construction of multi-level reactors at the nanometre scale remains a great challenge, but to regulate the reaction pathways within a reactor, designs of great intricacy are required. In this Review, we define the basic structural characteristics of porous nanoreactors, while also discussing the design principles and synthetic chemistry of these structures with respect to their emerging applications in energy storage and heterogeneous catalysis. Finally, we describe the difficulties of the structural optimization of these reactors and propose possible ways to improve porous nanoreactor design for future applications.

13.
Heliyon ; 10(19): e38050, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39386862

RESUMO

Objective: The NLRP3 (NOD-like receptor family, pyrin domain containing 3) inflammasome-driven immune-inflammatory response has been shown to play a critical role in epilepsy progression across multiple studies. While Ulinastatin (UTI), an immunomodulatory agent known to target the NLRP3 pathway in neurological disorders, its implications in epilepsy have not been extensively studied. This investigation aims to explore UTI's role and underlying mechanisms in epilepsy. Methods: To assess UTI's effects on epilepsy severity, neuroinflammation, and BBB integrity, a pentylenetetrazole (PTZ)-induced epilepsy model in mice and a co-culture system involving BV2 and HT22 cells stimulated by lipopolysaccharide (LPS) and ATP were employed. Techniques utilized included qPCR, Western blotting, ELISA, immunohistochemistry (IHC) staining, Evans Blue dye extravasation, glutamate assays, the Morris water maze, and Annexin V apoptosis assays. Results: In the PTZ model, UTI administration led to a substantial decrease in seizure intensity and susceptibility, inhibited NLRP3 inflammasome activation, reduced neuroinflammatory interactions, lowered hippocampal and systemic inflammatory mediator levels, and improved cognitive performance. Furthermore, UTI upregulated claudin-5 expression, a tight junction protein in the endothelium, and diminished Evans Blue dye leakage, indicating improved BBB integrity. In BV2 and HT22 cell co-culture models, UTI exerted neuroprotective effects by mitigating microglia-mediated neurotoxicity and fostering neuronal recovery. Conclusions: The findings demonstrate that UTI exerts transformative regulatory effects on the NLRP3 inflammasome in epilepsy models. This intervention effectively suppresses neuroinflammation, lessens seizure severity and susceptibility, and ameliorates epilepsy-related BBB dysfunction and cognitive impairments.

14.
JACS Au ; 4(7): 2666-2675, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39055150

RESUMO

Mesoporous materials endowed with a hollow structure offer ample opportunities due to their integrated functionalities; however, current approaches mainly rely on the recruitment of solid rigid templates, and feasible strategies with better simplicity and tunability remain infertile. Here, we report a novel emulsion-driven coassembly method for constructing a highly tailored hollow architecture in mesoporous carbon, which can be completely processed on oil-water liquid interfaces instead of a solid rigid template. Such a facile and flexible methodology relies on the subtle employment of a 1,3,5-trimethylbenzene (TMB) additive, which acts as both an emulsion template and a swelling agent, leading to a compatible integration of oil droplets and composite micelles. The solution-based assembly process also shows high controllability, endowing the hollow carbon mesostructure with a uniform morphology of hundreds of nanometers and tunable cavities from 0 to 130 nm in diameter and porosities (mesopore sizes 2.5-7.7 nm; surface area 179-355 m2 g-1). Because of the unique features in permeability, diffusion, and surface access, the hollow mesoporous carbon nanospheres exhibit excellent high rate and cycling performances for sodium-ion storage. Our study reveals a cooperative assembly on the liquid interface, which could provide an alternative toolbox for constructing delicate mesostructures and complex hierarchies toward advanced technologies.

15.
Small Methods ; : e2400069, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593363

RESUMO

Silicon (Si) is regarded as a promising anode material because of its outstanding theoretical capacity, abundant existence, and mature infrastructure, but it suffers from an inherent volume expansion problem. Herein, a facile, scalable, and cost-effective route to produce Si nanosheets (Si NSs) using a low-cost silica fume as the start materials is proposed. After coated with carbon, the as-prepared Si-NSs@C material delivers ultrahigh capability (2770 mAh g-1 at 0.1 C), high initial Coulombic efficiency (87.9%), and long cycling lifespan (100 cycles at 0.5 C with a capacity decay rate of 0.3% per cycle). Beyond proof of concept, this work demonstrates a Si-NSs based pouch cell with an impressive capacity retention of 70.9% after 400 cycles, making it more promising for practical application. Revealed by the theoretical simulation, kinetics analysis, and in situ thickness/pressure detection, it is found that the superior performance of Si-NSs is attributed to the improved diffusivity and reversibility of Li+ ions and low expansion.

16.
Adv Mater ; 36(44): e2409188, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39210633

RESUMO

Constructing nanoreactors with multiple active sites in well-defined crystalline mesoporous frameworks is an effective strategy for tailoring photocatalysts to address the challenging of CO2 reduction. Herein, one-dimensional (1-D) mesoporous single-crystal TiO2 nanorod (MS-TiO2-NRs, ≈110 nm in length, high surface area of 117 m2 g-1, and uniform mesopores of ≈7.0 nm) based nanoreactors are prepared via a droplet interface directed-assembly strategy under mild condition. By regulating the interfacial energy, the 1-D mesoporous single-crystal TiO2 can be further tuned to polycrystalline fan- and flower-like morphologies with different oxygen vacancies (Ov). The integration of single-crystal nature and mesopores with exposed oxygen vacancies make the rod-like TiO2 nanoreactors exhibit a high-photocatalytic CO2 reduction selectivity to CO (95.1%). Furthermore, photocatalytic cascade nanoreactors by in situ incorporation of CuW6O24 (W-Cu) clusters onto MS-TiO2-NRs via Ov are designed and synthesized, which improved the CO2 adsorption capacity and achieved two-step CO2-CO-CH4 photoreduction. The second step CO-to-CH4 reaction induced by W-Cu sites ensures a high generation rate of CH4 (420.4 µmol g-1 h-1), along with an enhanced CH4 selectivity (≈94.3% electron selectivity). This research provides a platform for the design of mesoporous single-crystal materials, which potentially extends to a range of functional ceramics and semiconductors for various applications.

17.
Natl Sci Rev ; 11(4): nwae054, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38545447

RESUMO

Due to their uncontrollable assembly and crystallization process, the synthesis of mesoporous metal oxide single crystals remains a formidable challenge. Herein, we report the synthesis of single-crystal-like mesoporous Li2TiSiO5 by using soft micelles as templates. The key lies in the atomic-scale self-assembly and step-crystallization processes, which ensure the formation of single-crystal-like mesoporous Li2TiSiO5 microparticles via an oriented attachment growth mechanism under the confinement of an in-situ formed carbon matrix. The mesoporous Li2TiSiO5 anode achieves a superior rate capability (148 mAh g-1 at 5.0 A g-1) and outstanding long-term cycling stability (138 mAh g-1 after 3000 cycles at 2.0 A g-1) for lithium storage as a result of the ultrafast Li+ diffusion caused by penetrating mesochannels and nanosized crystal frameworks (5-10 nm). In comparison, bulk Li2TiSiO5 exhibits poor rate capability and cycle performance due to micron-scale diffusion lengths. This method is very simple and reproducible, heralding a new way of designing and synthesizing mesoporous single crystals with controllable frameworks and chemical functionalities.

18.
Radiol Oncol ; 57(4): 455-464, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038425

RESUMO

BACKGROUND: The purpose of our study was to explore and compare the tumor burden of different bone marrow infiltration patterns and evaluate the feasibility of apparent diffusion coefficient (ADC) value to identify patterns in multiple myeloma (MM). PATIENTS AND METHODS: Ninety-three patients with newly diagnosed multiple myeloma and 23 controls had undergone routine magnetic resonance imaging (MRI) and diffusion-weighted MRI (DWI) from January 2019 to November 2020. Five bone marrow (BM) infiltration patterns were allocated according to routine MRI. The laboratory data and ADC values of patterns were analyzed and compared. ROC analysis was used to establish the best diagnostic ADC threshold value for identifying these patterns and distinguishing normal pattern from controls. Besides, the correlation between the ADC values of diffuse pattern and the plasma cells ratio was assessed. RESULTS: The values of hemoglobin, beta-2 microglobulin (ß2-MG), plasma cell, M protein, the percentages of stage, high-risk fluorescence in situ hybridization, and ADC values showed significant difference among patterns. ADCmean at a specific value (368.5×10-6 mm2/s) yielded a maximum specificity (95.5%) and sensitivity (92.0%) in diagnosing MM. A specific value (335.5×10-6mm2/s) yielded a maximum specificity (84.7%) and sensitivity (88.0%) in discriminating visually normal pattern in MM from controls. There was a moderate positive correlation between the plasma cells ratio and ADCs of diffuse infiltration patterns (r = 0.648, P < 0.001). CONCLUSIONS: The bone marrow infiltration patterns in MM patients can indicate the tumor burden and ADC value has the ability to discriminate these patterns objectively.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/diagnóstico por imagem , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Estudos de Viabilidade , Carga Tumoral , Hibridização in Situ Fluorescente
19.
JACS Au ; 3(4): 1141-1150, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37124304

RESUMO

Mesoporous materials with crystalline frameworks have been acknowledged as very attractive materials in various applications. Nevertheless, due to the cracking issue during crystallization and incompatible hydrolysis and assembly, the precise control for crystalline mesoscale membranes is quite infertile. Herein, we presented an ingenious stepwise monomicelle assembly route for the syntheses of highly ordered mesoporous crystalline TiO2 membranes with delicately controlled mesophase, mesoporosity, and thickness. Such a process involves the preparation of monomicelle hydrogels and follows self-assembly by stepwise solvent evaporation, which enables the sensitive hydrolysis of TiO2 oligomers and dilatory micelle assembly to be united. In consequence, the fabricated mesoporous TiO2 membranes exhibit a broad flexibility, including tunable ordered mesophases (worm-like, hexagonal p6mm to body-centered cubic Im3̅m), controlled mesopore sizes (3.0-8.0 nm), and anatase grain sizes (2.3-8.4 nm). Besides, such mesostructured crystalline TiO2 membranes can be extended to diverse substrates (Ti, Ag, Si, FTO) with tailored thickness. The great mesoporosity of the in situ fabricated mesoscopic membranes also affords excellent pseudocapacitive behavior for sodium ion storage. This study underscores a novel pathway for balancing the interaction of precursors and micelles, which could have implications for synthesizing crystalline mesostructures in higher controllability.

20.
Nat Commun ; 13(1): 6136, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253472

RESUMO

Multi-chambered architectures have attracted much attention due to the ability to establish multifunctional partitions in different chambers, but manipulating the chamber numbers and coupling multi-functionality within the multi-chambered mesoporous nanoparticle remains a challenge. Herein, we propose a nanodroplet remodeling strategy for the synthesis of hierarchical multi-chambered mesoporous silica nanoparticles with tunable architectures. Typically, the dual-chambered nanoparticles with a high surface area of ~469 m2 g-1 present two interconnected cavities like a calabash. Furthermore, based on this nanodroplet remodeling strategy, multiple species (magnetic, catalytic, optic, etc.) can be separately anchored in different chamber without obvious mutual-crosstalk. We design a dual-chambered mesoporous nanoreactors with spatial isolation of Au and Pd active-sites for the cascade synthesis of 2-phenylindole from 1-nitro-2-(phenylethynyl)benzene. Due to the efficient mass transfer of reactants and intermediates in the dual-chambered structure, the selectivity of the target product reaches to ~76.5%, far exceeding that of single-chambered nanoreactors (~41.3%).

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