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1.
Nat Commun ; 15(1): 5806, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987569

RESUMO

Hydrogenation is a versatile chemical process with significant applications in various industries, including food production, petrochemical refining, pharmaceuticals, and hydrogen carriers/safety. Traditional hydrogenation of aromatics, hindered by the stable π-conjugated phenyl ring structures, typically requires high temperatures and pressures, making ambient hydrogenation a grand challenge. Herein, we introduce a PdPtRuCuNi high entropy alloy (HEA) nanocatalyst, achieving an exceptional 100% hydrogenation of carbon-carbon unsaturated bonds, including alkynyl and phenyl groups, in solid 1,4-bis(phenylethynyl)benzene (DEB) at 25 °C under ≤1 bar H2 and solventless condition. This results in a threefold higher hydrogen uptake for DEB-contained composites compared to conventional Pd catalysts, which can only hydrogenate the alkynyl groups with a ~ 27% conversion of DEB. Our experimental results, complemented by theoretical calculations, reveal that PdPtRu alloy is highly active and crucial in enabling the hydrogenation of phenyl groups, while all five elements work synergistically to regulate the reaction rate. Remarkably, this newly developed catalyst also achieves nearly 100% reactivity for ambient hydrogenation of a broad range of aromatics, suggesting its universal effectiveness. Our research uncovers a novel material platform and catalyst design principle for efficient and general hydrogenation. The multi-element synergy in HEA also promises unique catalytic behaviors beyond hydrogenation applications.

2.
Mol Brain ; 17(1): 45, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044257

RESUMO

Identifying sensitive and specific measures that can quantify myelin are instrumental in characterizing microstructural changes in neurological conditions. Neuroimaging transcriptomics is emerging as a valuable technique in this regard, offering insights into the molecular basis of promising candidates for myelin quantification, such as myelin water fraction (MWF). We aimed to demonstrate the utility of neuroimaging transcriptomics by validating MWF as a myelin measure. We utilized data from a normative MWF brain atlas, comprised of 50 healthy subjects (mean age = 25 years, range = 17-42 years) scanned at 3 Tesla. Magnetic resonance imaging data included myelin water imaging to extract MWF and T1 anatomical scans for image registration and segmentation. We investigated the inter-regional distributions of gene expression data from the Allen Human Brain Atlas in conjunction with inter-regional MWF distribution patterns. Pearson correlations were used to identify genes with expression profiles mirroring MWF. The Single Cell Type Atlas from the Human Protein Atlas was leveraged to classify genes into gene sets with high cell type specificity, and a control gene set with low cell type specificity. Then, we compared the Pearson correlation coefficients for each gene set to determine if cell type-specific gene expression signatures correlate with MWF. Pearson correlation coefficients between MWF and gene expression for oligodendrocytes and adipocytes were significantly higher than for the control gene set, whereas correlations between MWF and inhibitory/excitatory neurons were significantly lower. Our approach in integrating transcriptomics with neuroimaging measures supports an emerging technique for understanding and validating MRI-derived markers such as MWF.


Assuntos
Bainha de Mielina , Oligodendroglia , Transcriptoma , Água , Humanos , Bainha de Mielina/metabolismo , Adulto , Transcriptoma/genética , Adolescente , Oligodendroglia/metabolismo , Adulto Jovem , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Regulação da Expressão Gênica
3.
Front Pharmacol ; 15: 1410565, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989142

RESUMO

We aimed to investigate the expression and motor modulatory roles of several mechano-sensitive channels (MSCs) in human ureter. Human proximal ureters were obtained from eighty patients subjected to nephrectomy. Expression of MSCs at mRNA, protein and functional levels were examined. Contractions of longitudinal ureter strips were recorded in organ bath. A fluorescent probe Diaminofluoresceins was used to measure nitric oxide (NO). RT-PCR analyses revealed predominant expression of Piezo1 and TRPV2 mRNA in intact ureter and mucosa. Immunofluorescence assays indicate proteins of MSCs (Piezo1/Piezo2, TRPV2 and TRPV4) were mainly distributed in the urothelium. Ca2+ imaging confirmed functional expression of TRPV2, TRPV4 and Piezo1 in cultured urothelial cells. Specific agonists of Piezo1 (Yoda1, 3-300 µM) and TRPV2 (cannabidiol, 3-300 µM) attenuated the frequency of ureteral contractions in a dose-dependent manner while the TRPV4 agonist GSK1016790A (100 nM-1 µM) exerted no effect. The inhibitory effects of Piezo1 and TRPV2 agonists were significantly blocked by the selective antagonists (Dooku 1 for Piezo1, Tranilast for TRPV2), removal of the mucosa, and pretreatment with NO synthase inhibitor L-NAME (10 µM). Yoda1 (30 µM) and cannabidiol (50 µM) increased production of NO in cultured urothelial cells. Our results suggest that activation of Piezo1 or TRPV2 evokes NO production and release from mucosa that may mediate mechanical stimulus-induced reduction of ureter contractions. Our findings support the idea that targeting Piezo1 and TRPV2 channels may be a promising pharmacological strategy for ureter stone passage or colic pain relief.

4.
Glia ; 72(10): 1893-1914, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39023138

RESUMO

Myelin Basic Protein (MBP) is essential for both elaboration and maintenance of CNS myelin, and its reduced accumulation results in hypomyelination. How different Mbp mRNA levels affect myelin dimensions across the lifespan and how resident glial cells may respond to such changes are unknown. Here, to investigate these questions, we used enhancer-edited mouse lines that accumulate Mbp mRNA levels ranging from 8% to 160% of wild type. In young mice, reduced Mbp mRNA levels resulted in corresponding decreases in Mbp protein accumulation and myelin sheath thickness, confirming the previously demonstrated rate-limiting role of Mbp transcription in the control of initial myelin synthesis. However, despite maintaining lower line specific Mbp mRNA levels into old age, both MBP protein levels and myelin thickness improved or fully normalized at rates defined by the relative Mbp mRNA level. Sheath length, in contrast, was affected only when mRNA levels were very low, demonstrating that sheath thickness and length are not equally coupled to Mbp mRNA level. Striking abnormalities in sheath structure also emerged with reduced mRNA levels. Unexpectedly, an increase in the density of all glial cell types arose in response to reduced Mbp mRNA levels. This investigation extends understanding of the role MBP plays in myelin sheath elaboration, architecture, and plasticity across the mouse lifespan and illuminates a novel axis of glial cell crosstalk.


Assuntos
Proteína Básica da Mielina , Bainha de Mielina , Neuroglia , RNA Mensageiro , Animais , Proteína Básica da Mielina/metabolismo , Proteína Básica da Mielina/genética , Bainha de Mielina/metabolismo , Bainha de Mielina/genética , RNA Mensageiro/metabolismo , Neuroglia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Masculino
7.
J Org Chem ; 89(11): 7770-7779, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38738957

RESUMO

A visible-light-enabled photoredox radical cascade cyclization of 2-vinyl benzimidazole derivatives is developed. This chemistry is applicable to a wide range of N-aroyl 2-vinyl benzimidazoles as acceptors, and halo compounds, including alkyl halides, acyl chlorides and sulfonyl chlorides, as radical precursors. The Langlois reagent also serves as an effective partner in this photocatalytic oxidative cascade process. This protocol provides a robust alternative for rendering highly functionalized benzo[4,5]imidazo[1,2-b]isoquinolin-11(6H)-ones.

8.
Materials (Basel) ; 17(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38793246

RESUMO

To understand the fracture properties of the nitrate ester plasticized polyether (NEPE) propellant, single-edge notched tension (SENT) tests were carried out at room temperature (20 °C) under different tensile rates (10-500 mm/min). The mechanical response, crack morphology, evolution path, and crack propagation velocity during the fracture process were studied using a combination of a drawing machine and a high-speed camera. The mode I critical stress intensity factor KIc was calculated to analyze the tensile fracture toughness of the NEPE propellant, and a criterion related to KIc was proposed as a means of determining whether the solid rocket motors can normally work. The experimental results demonstrated that the NEPE propellant exhibited blunting fracture phenomena during crack propagation, resulting in fluctuating crack propagation velocity. The fracture toughness of the NEPE propellant exhibited clear rate dependence. When the tensile rate increased from 10 mm/min to 500 mm/min, the magnitude of the critical stress intensity factor increased by 62.3%. Moreover, numerical studies based on bond-based peridynamic (BBPD) were performed by modeling the fracture process of the NEPE propellant, including the crack propagation speed and the load-displacement curve of the NEPE propellant. The simulation results were then compared with the experiments.

9.
Biomaterials ; 309: 122610, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38749307

RESUMO

Precise image-guided cancer immunotherapy holds immense potential in revolutionizing cancer treatment. The strategies facilitating activatable imaging and controlled therapeutics are highly desired yet to be developed. Herein, we report a new pyroptosis nanoinducer that integrates aggregation-induced emission luminogen (AIEgen) and DNA methyltransferase inhibitor with hypoxia-responsive covalent organic frameworks (COFs) for advanced image-guided cancer immunotherapy. We first synthesize and compare three donor-acceptor type AIEgens featuring varying numbers of electron-withdrawing units, and find that the incorporation of two acceptors yields the longest response wavelength and most effective photodynamic therapy (PDT) property, surpassing the performance of analogs with one or three acceptor groups. A COF-based nanoplatform containing AIEgen and pyroptosis drug is successfully constructed via the one-pot method. The intra-COF energy transfer significantly quenches AIEgen, in which both fluorescence and PDT properties greatly enhance upon hypoxia-triggered COF degradation. Moreover, the photodynamic process exacerbates hypoxia, accelerating pyroptosis drug release. The nanoagent enables sensitive delineation of tumor site through in situ activatable fluorescence signature. Thanks to the exceptional ROS production capabilities and hypoxia-accelerating drug release, the nanoagent not only inhibits primary tumor growth but also impedes the progression of distant tumors in 4T1 tumor-bearing mice through potent pyroptosis-mediated immune response. This research introduces a novel strategy for achieving activatable phototheranostics and self-accelerating drug release for synergetic cancer immunotherapy.


Assuntos
Imunoterapia , Fotoquimioterapia , Piroptose , Piroptose/efeitos dos fármacos , Animais , Imunoterapia/métodos , Camundongos , Fotoquimioterapia/métodos , Humanos , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Feminino , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Nanopartículas/química , Estruturas Metalorgânicas/química
12.
Future Med Chem ; 16(9): 887-903, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618977

RESUMO

Background: The epidemic caused by SARS-CoV-2 swept the world in 2019. The 3C-like protease (3CLpro) of SARS-CoV-2 plays a key role in viral replication, and its inhibition could inhibit viral replication. Materials & methods: The virtual screen based on receptor-ligand pharmacophore models and molecular docking were conducted to obtain the novel scaffolds of the 3CLpro. The molecular dynamics simulation was also carried out. All compounds were synthesized and evaluated in biochemical assays. Results: The compound C2 could inhibit 3CLpro with a 72% inhibitory rate at 10 µM. The covalent docking showed that C2 could form a covalent bond with the Cys145 in 3CLpro. Conclusion: C2 could be a potent lead compound of 3CLpro inhibitors against SARS-CoV-2.


[Box: see text].


Assuntos
Antivirais , Proteases 3C de Coronavírus , Desenho de Fármacos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , SARS-CoV-2 , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/síntese química , Antivirais/química , Humanos , Inibidores de Proteases/farmacologia , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , Tratamento Farmacológico da COVID-19 , Relação Estrutura-Atividade
14.
Expert Opin Ther Pat ; 34(3): 99-126, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38648107

RESUMO

INTRODUCTION: The TGF-ß signaling pathway is a complex network that plays a crucial role in regulating essential biological functions and is implicated in the onset and progression of multiple diseases. This review highlights the recent advancements in developing inhibitors targeting the TGF-ß signaling pathway and their potential therapeutic applications in various diseases. AREA COVERED: The review discusses patents on active molecules related to the TGF-ß signaling pathway, focusing on three strategies: TGF-ß activity inhibition, blocking TGF-ß receptor binding, and disruption of the signaling pathway using small molecule inhibitors. Combination therapies and the development of fusion proteins targeting multiple pathways are also explored. The literature search was conducted using the Cortellis Drug Discovery Intelligence database, covering patents from 2021 onwards. EXPERT OPINION: The development of drugs targeting the TGF-ß signaling pathway has made significant progress in recent years. However, addressing challenges such as specificity, systemic toxicity, and patient selection is crucial for their successful clinical application. Targeting the TGF-ß signaling pathway holds promise as a promising approach for the treatment of various diseases.


Assuntos
Desenvolvimento de Medicamentos , Terapia de Alvo Molecular , Patentes como Assunto , Receptores de Fatores de Crescimento Transformadores beta , Transdução de Sinais , Fator de Crescimento Transformador beta , Humanos , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Descoberta de Drogas
15.
Nat Commun ; 15(1): 2046, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448407

RESUMO

Continuous industrialization and other human activities have led to severe water quality deterioration by harmful pollutants. Achieving robust and high-throughput water purification is challenging due to the coupling between mechanical strength, mass transportation and catalytic efficiency. Here, a structure-function integrated system is developed by Douglas fir wood-inspired metamaterial catalysts featuring overlapping microlattices with bimodal pores to decouple the mechanical, transport and catalytic performances. The metamaterial catalyst is prepared by metal 3D printing (316 L stainless steel, mainly Fe) and electrochemically decorated with Co to further boost catalytic functionality. Combining the flexibility of 3D printing and theoretical simulation, the metamaterial catalyst demonstrates a wide range of mechanical-transport-catalysis capabilities while a 70% overlap rate has 3X more strength and surface area per unit volume, and 4X normalized reaction kinetics than those of traditional microlattices. This work demonstrates the rational and harmonious integration of structural and functional design in robust and high throughput water purification, and can inspire the development of various flow catalysts, flow batteries, and functional 3D-printed materials.

16.
J Chem Inf Model ; 64(8): 3047-3058, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38520328

RESUMO

Covalent drugs exhibit advantages in that noncovalent drugs cannot match, and covalent docking is an important method for screening covalent lead compounds. However, it is difficult for covalent docking to screen covalent compounds on a large scale because covalent docking requires determination of the covalent reaction type of the compound. Here, we propose to use deep learning of a lateral interactions spiking neural network to construct a covalent lead compound screening model to quickly screen covalent lead compounds. We used the 3CL protease (3CL Pro) of SARS-CoV-2 as the screen target and constructed two classification models based on LISNN to predict the covalent binding and inhibitory activity of compounds. The two classification models were trained on the covalent complex data set targeting cysteine (Cys) and the compound inhibitory activity data set targeting 3CL Pro, respected, with good prediction accuracy (ACC > 0.9). We then screened the screening compound library with 6 covalent binding screening models and 12 inhibitory activity screening models. We tested the inhibitory activity of the 32 compounds, and the best compound inhibited SARS-CoV-2 3CL Pro with an IC50 value of 369.5 nM. Further assay implied that dithiothreitol can affect the inhibitory activity of the compound to 3CL Pro, indicating that the compound may covalently bind 3CL Pro. The selectivity test showed that the compound had good target selectivity to 3CL Pro over cathepsin L. These correlation assays can prove the rationality of the covalent lead compound screening model. Finally, covalent docking was performed to demonstrate the binding conformation of the compound with 3CL Pro. The source code can be obtained from the GitHub repository (https://github.com/guzh970630/Screen_Covalent_Compound_by_LISNN).


Assuntos
Proteases 3C de Coronavírus , Simulação de Acoplamento Molecular , Redes Neurais de Computação , SARS-CoV-2 , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/química , SARS-CoV-2/enzimologia , SARS-CoV-2/efeitos dos fármacos , Humanos , Descoberta de Drogas , Antivirais/farmacologia , Antivirais/química , Antivirais/metabolismo , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Tratamento Farmacológico da COVID-19 , Aprendizado Profundo , Ligação Proteica , COVID-19/virologia
17.
Neural Netw ; 174: 106244, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508047

RESUMO

Spiking Neural Networks (SNNs) have become one of the most prominent next-generation computational models owing to their biological plausibility, low power consumption, and the potential for neuromorphic hardware implementation. Among the various methods for obtaining available SNNs, converting Artificial Neural Networks (ANNs) into SNNs is the most cost-effective approach. The early challenges in ANN-to-SNN conversion work revolved around the susceptibility of converted SNNs to conversion errors. Some recent endeavors have attempted to mitigate these conversion errors by altering the original ANNs. Despite their ability to enhance the accuracy of SNNs, these methods lack generality and cannot be directly applied to convert the majority of existing ANNs. In this paper, we present a framework named DNISNM for converting ANN to SNN, with the aim of addressing conversion errors arising from differences in the discreteness and asynchrony of network transmission between ANN and SNN. The DNISNM consists of two mechanisms, Data-based Neuronal Initialization (DNI) and Signed Neuron with Memory (SNM), designed to respectively address errors stemming from discreteness and asynchrony disparities. This framework requires no additional modifications to the original ANN and can result in SNNs with improved accuracy performance, simultaneously ensuring universality, high precision, and low inference latency. We verify it experimentally on challenging object recognition datasets, including CIFAR10, CIFAR100, and ImageNet-1k. Experimental results show that the SNN converted by our framework has very high accuracy even at extremely low latency.


Assuntos
Redes Neurais de Computação , Neurônios , Bases de Dados Factuais , Percepção Visual
18.
Nanoscale ; 16(9): 4628-4636, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38357835

RESUMO

Hydrogel-based solar vapour generators (SVGs) are promising for wastewater treatment and desalination. The performance of SVG systems is governed by solar thermal conversion and water management. Progress has been made in achieving high energy conversion efficiency, but the water evaporation rates are still unsatisfactory under 1 sun irradiation. This study introduced novel two-dimensional (2D) boron nanosheets as additives into hydrogel-based SVGs. The resulting SVGs exhibit an outstanding evaporation rate of 4.03 kg m-2 h-1 under 1 sun irradiation. This significant improvement is attributed to the 2D boron nanosheets, which leads to the formation of a higher content of intermediate water and reduced water evaporation enthalpy to 845.11 kJ kg-1. The SVGs into which boron nanosheets were incorporated also showed high salt resistance and durability, demonstrating their great potential for desalination applications.

19.
Sensors (Basel) ; 24(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38400236

RESUMO

Pressure sensing plays an important role in many industrial fields; conventional electronic pressure sensors struggle to survive in the harsh environment. Recently microelectromechanical systems (MEMS) fiber-optic Fabry-Perot (FP) pressure sensors have attracted great interest. Here we review the basic principles of MEMS fiber-optic FP pressure sensors and then discuss the sensors based on different materials and their industrial applications. We also introduce recent progress, such as two-photon polymerization-based 3D printing technology, and the state-of-the-art in this field, e.g., sapphire-based sensors that work up to 1200 °C. Finally, we discuss the limitations and opportunities for future development.

20.
Hypertens Res ; 47(5): 1103-1119, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38228750

RESUMO

This comprehensive review offers a thorough exploration of recent advancements in our understanding of the intricate cardiovascular complications associated with Primary Aldosteronism (PA). PA encompasses a spectrum of conditions characterized by hypertension and excessive production of aldosterone operating independently of the renin-angiotensin system. Given its association with an elevated risk of cardiovascular and cerebrovascular complications, as well as a higher incidence of metabolic syndrome in comparison to individuals with essential hypertension (EH), an accurate diagnosis of PA is of paramount importance. This review delves into the intricate interplay between PA and cardiovascular health and focuses on the key pathophysiological mechanisms contributing to adverse cardiac outcomes. The impact of different treatment modalities on cardiovascular health is also examined, offering insights into potential therapeutic approaches. By highlighting the significance of recognizing PA as a significant contributor to cardiovascular morbidity, this review emphasizes the need for improved screening, early diagnosis, and tailored management strategies to both enhance patient care and mitigate the burden of cardiovascular diseases. The findings presented herein underscore the growing importance of PA in the context of cardiovascular medicine and emphasize the potential for translating these insights into targeted interventions to improve patient outcomes.


Assuntos
Doenças Cardiovasculares , Hiperaldosteronismo , Humanos , Doenças Cardiovasculares/etiologia , Hiperaldosteronismo/complicações , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/epidemiologia , Hiperaldosteronismo/terapia , Aldosterona/metabolismo , Adrenalectomia
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