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1.
Nutrients ; 16(17)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39275260

RESUMEN

Insomnia is a common sleep disorder that significantly impacts individuals' sleep quality and daily life. Recent studies have suggested that gut microbiota may influence sleep through various metabolic pathways. This study aims to explore the causal relationships between the abundance of gut microbiota metabolic pathways and insomnia using Mendelian randomization (MR) analysis. This two-sample MR study used genetic data from the OpenGWAS database (205 gut bacterial pathway abundance) and the FinnGen database (insomnia-related data). We identified single nucleotide polymorphisms (SNPs) associated with gut bacterial pathway abundance as instrumental variables (IVs) and ensured their validity through stringent selection criteria and quality control measures. The primary analysis employed the inverse variance-weighted (IVW) method, supplemented by other MR methods, to estimate causal effects. The MR analysis revealed significant positive causal effects of specific carbohydrate, amino acid, and nucleotide metabolism pathways on insomnia. Key pathways, such as gluconeogenesis pathway (GLUCONEO.PWY) and TCA cycle VII acetate producers (PWY.7254), showed positive associations with insomnia (B > 0, p < 0.05). Conversely, pathways like hexitol fermentation to lactate, formate, ethanol and acetate pathway (P461.PWY) exhibited negative causal effects (B < 0, p < 0.05). Multivariable MR analysis confirmed the independent causal effects of these pathways (p < 0.05). Sensitivity analyses indicated no significant pleiotropy or heterogeneity, ensuring the robustness of the results. This study identifies specific gut microbiota metabolic pathways that play critical roles in the development of insomnia. These findings provide new insights into the biological mechanisms underlying insomnia and suggest potential targets for therapeutic interventions. Future research should further validate these causal relationships and explore how modulating gut microbiota or its metabolic products can effectively improve insomnia symptoms, leading to more personalized and precise treatment strategies.


Asunto(s)
Microbioma Gastrointestinal , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Trastornos del Inicio y del Mantenimiento del Sueño/microbiología , Trastornos del Inicio y del Mantenimiento del Sueño/metabolismo , Trastornos del Inicio y del Mantenimiento del Sueño/genética , Redes y Vías Metabólicas/genética
2.
Ann Hepatol ; : 101571, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39276987

RESUMEN

INTRODUCTION AND OBJECTIVES: This research aims to evaluate the efficacy and safety of prophylactic antibiotics in patients with alcohol-related liver disease (ALD). MATERIALS AND METHODS: We systematically searched databases including PubMed, Embase, Cochrane, and Web of Science up to October 2023. Our scope encompassed the influence of prophylactic antibiotics on all-cause mortality, infection, variceal bleeding, hepatic encephalopathy (HE), hepatorenal syndrome (HRS), adverse events (AE), fungal infection, clostridioides difficile infection (CDI), and multidrug-resistant (MDR) bacterial infection. Additionally, total bilirubin, creatinine, platelet counts, and plasma endotoxin levels were also analyzed. RESULTS: After comprehensive selection, 10 studies with 974 participants were included for further analysis. The study demonstrated that prophylactic antibiotic therapy was associated with reductions in infection rates, HE incidence, variceal bleeding, and all-cause mortality. The treatment did not increase the incidence of AE, fungal infection, and CDI, but it did raise the MDR bacteria infection rate. The analysis revealed no significant protective effect of antibiotic prophylaxis on total bilirubin and creatinine levels. Furthermore, the administration of antibiotics led to marginal increases in platelet counts, a minor reduction in endotoxin concentrations, and a subtle enhancement in HRS; however, these changes did not reach statistical significance. CONCLUSIONS: Prophylactic antibiotic therapy was an effective and safe treatment for advanced ALD. To mitigate the risk of MDR bacterial infections, a strategy of selective intestinal decontamination could be advisable. Future investigations should prioritize varied ALD patient populations with extended follow-up periods and assorted antibiotic regimens to solidify the efficacy and safety of ALD treatments.

3.
Food Funct ; 15(18): 9165-9175, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39157962

RESUMEN

Atrial fibrillation (AF) is the most prevalent sustained tachyarrhythmia in patients with cardiovascular diseases. Recently, it has been discovered that oxidative stress is an important contributor to AF. Therefore, antioxidant therapies for AF have great potential for clinical applications. Methionine, a sulfur-containing amino acid residue other than cysteine, is recognized as a functional redox switch, which could be rescued from the reversible oxidation of methionine sulfoxide by methionine sulfoxide reductase A (MsrA). S-Methyl-L-cysteine (SMLC), a natural analogue of Met, which is abundantly found in garlic and cabbage, could substitute for Met oxidations and mediate MsrA to scavenge free radicals. However, whether SMLC alleviates AF is unclear. This study aims to clarify the effects of SMLC on AF and elucidate the underlying pharmacological and molecular mechanisms. In vivo, SMLC (70, 140 and 280 mg kg-1 day-1) was orally administered to mice for 4 weeks with angiotensin II (Ang II) by subcutaneous infusion using osmotic pumps to induce AF. Ang II significantly prompted high AF susceptibility and atrial remodeling characterized by oxidative stress, conductive dysfunction and fibrosis. SMLC played a remarkable protective role in Ang II-induced atrial remodeling dose-dependently. Moreover, RNA sequencing was performed on atrial tissues to identify the differentially expressed mRNA, which was to screen out MSRA, CAMK2 and MAPK signaling pathways. Western blots confirmed that Ang II-induced downregulation of MsrA and upregulation of oxidized CaMKII (ox-CaMKII) and p38 MAPK could be reversed in a concentration-dependent manner by SMLC. To investigate the underlying mechanisms, HL-1 cells (mouse atria-derived cardiomyocytes) treated with Ang II were used for an in vitro model. SMLC alleviated Ang II-induced cytotoxicity, mitochondrial damage and oxidative stress. Additionally, knockdown MsrA could attenuate the protective effects of SMLC, which were eliminated by the p38 MAPK inhibitor SB203580. In summary, the present study demonstrates that SMLC protects against atrial remodeling in AF by inhibiting oxidative stress through the mediation of the MsrA/p38 MAPK signaling pathway.


Asunto(s)
Angiotensina II , Remodelación Atrial , Ratones Endogámicos C57BL , Estrés Oxidativo , Proteínas Quinasas p38 Activadas por Mitógenos , Animales , Ratones , Estrés Oxidativo/efectos de los fármacos , Angiotensina II/farmacología , Angiotensina II/análogos & derivados , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Masculino , Remodelación Atrial/efectos de los fármacos , Metionina Sulfóxido Reductasas/metabolismo , Metionina Sulfóxido Reductasas/genética , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Cisteína/análogos & derivados , Cisteína/farmacología
4.
Artículo en Inglés | MEDLINE | ID: mdl-39166388

RESUMEN

OBJECTIVE: The aim of this study is to systematically examine and compare the characteristics distinguishing colorectal adenomatous polyps from normal mucosal intestinal microbiota. METHODS: A total of 30 specimens were obtained from patients diagnosed with colorectal adenomatous polyps (adenoma group) who underwent endoscopic removal at Wenzhou People's Hospital between September 2021 and November 2021. Concurrently, 30 normal mucosal specimens were collected from patients without adenomatous polyps (control group). Subsequently, microbiome total DNA extraction was carried out, followed by PCR amplification targeting the V3-V4 region of the 16S rDNA. High-throughput sequencing was conducted using the Illumina MiSeq platform. Subsequent to sequencing, bioinformatics analysis was used to assess the diversity, composition, and functional aspects of the intestinal microbiota in both study groups. RESULTS: A notable dissimilarity in the microbiota structure was identified, specifically within the transverse colon, between these two groups (P < 0.05). Species composition analysis revealed that Escherichia, Fusobacterium, and Bacteroides were predominant bacteria in both groups, with Escherichia and Enterobacter displaying significant differences at the genera level between the control group and the adenoma group (P < 0.05). Correlation analysis and functional prediction demonstrated substantial disparities in interactions among dominant intestinal microbial genera within patients from both groups. Additionally, it was discovered that the intestinal microbiomes in patients in the adenoma group exhibited a significantly higher pathogenic potential. CONCLUSION: Upon conducting a comprehensive analysis, it was discerned that the microbiota present in the transverse colon of the control group exhibited distinctive characteristics that may contribute to the maintenance of intestinal health.

5.
Eur J Med Chem ; 276: 116664, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39018921

RESUMEN

Colorectal cancer (CRC) has been becoming one of the most common causes of cancer mortality worldwide. Accumulating studies suggest that the progressive up-regulation of Wnt/ß-catenin signaling is a crucial hallmark of CRC, and suppressing it is a promising strategy to treat CRC. Herein, we reported our latest efforts in the discovery of novel fused tetrahydroisoquinoline derivatives with good anti-CRC activities by screening our in-house berberine-like library and further structure-activity relationship (SAR) studies, in which we identified compound 10 is a potent lead compound with significant antiproliferation potencies. By the biotinylated probe and LC-MS/MS study, Hsp90 was identified as its molecular target, which is a fully different mechanism of action from what we reported before. Further studies showed compound 10 directly engaged the N-terminal site of Hsp90 and promoted the degradation of ß-catenin, thereby suppressing the Wnt/ß-catenin signaling. More importantly, compound 10 exhibits favorable pharmacokinetic parameters and significant anti-tumor efficacies in the HCT116 xenograft model. Taken together, this study furnished the discovery of candidate drug compound 10 possessing a novel fused tetrahydroisoquinoline scaffold with excellent in vitro and in vivo anti-CRC activities by targeting Hsp90 to disturb Wnt/ß-catenin signaling pathway, which lay a foundation for discovering more effective CRC-targeted therapies.


Asunto(s)
Antineoplásicos , Proliferación Celular , Neoplasias Colorrectales , Ensayos de Selección de Medicamentos Antitumorales , Tetrahidroisoquinolinas , Vía de Señalización Wnt , beta Catenina , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , Tetrahidroisoquinolinas/farmacología , Tetrahidroisoquinolinas/química , Tetrahidroisoquinolinas/síntesis química , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Relación Estructura-Actividad , Animales , Proliferación Celular/efectos de los fármacos , beta Catenina/metabolismo , beta Catenina/antagonistas & inhibidores , Ratones , Estructura Molecular , Relación Dosis-Respuesta a Droga , Ratones Desnudos , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Proteínas HSP90 de Choque Térmico/metabolismo , Ratones Endogámicos BALB C
6.
Cell Metab ; 36(8): 1806-1822.e11, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-38897198

RESUMEN

Immune checkpoint blockade has led to breakthroughs in the treatment of advanced gastric cancer. However, the prominent heterogeneity in gastric cancer, notably the heterogeneity of the tumor microenvironment, highlights the idea that the antitumor response is a reflection of multifactorial interactions. Through transcriptomic analysis and dynamic plasma sample analysis, we identified a metabolic "face-off" mechanism within the tumor microenvironment, as shown by the dual prognostic significance of nicotinamide metabolism. Specifically, macrophages and fibroblasts expressing the rate-limiting enzymes nicotinamide phosphoribosyltransferase and nicotinamide N-methyltransferase, respectively, regulate the nicotinamide/1-methylnicotinamide ratio and CD8+ T cell function. Mechanistically, nicotinamide N-methyltransferase is transcriptionally activated by the NOTCH pathway transcription factor RBP-J and is further inhibited by macrophage-derived extracellular vesicles containing nicotinamide phosphoribosyltransferase via the SIRT1/NICD axis. Manipulating nicotinamide metabolism through autologous injection of extracellular vesicles restored CD8+ T cell cytotoxicity and the anti-PD-1 response in gastric cancer.


Asunto(s)
Macrófagos , Niacinamida , Nicotinamida Fosforribosiltransferasa , Neoplasias Gástricas , Microambiente Tumoral , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Humanos , Macrófagos/metabolismo , Niacinamida/análogos & derivados , Niacinamida/farmacología , Nicotinamida Fosforribosiltransferasa/metabolismo , Animales , Ratones , Fibroblastos/metabolismo , Nicotinamida N-Metiltransferasa/metabolismo , Línea Celular Tumoral , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/inmunología , Femenino , Masculino , Vesículas Extracelulares/metabolismo
7.
Nano Lett ; 24(19): 5920-5928, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38708934

RESUMEN

A significant challenge in direct seawater electrolysis is the rapid deactivation of the cathode due to the large scaling of Mg(OH)2. Herein, we synthesized a Pt-coated highly disordered NiCu alloy (Pt-NiCu alloy) electrode with superior solidophobic behavior, enabling stable hydrogen generation (100 mA cm-2, >1000 h durability) and simultaneous production of Mg(OH)2 (>99.0% purity) in electrolyte enriched with Mg2+ and Ca2+. The unconventional solidophobic property primarily stems from the high surface energy of the NiCu alloy substrate, which facilitates the adsorption of surface water and thereby compels the bulk formation of Mg(OH)2 via homogeneous nucleation. The discovery of this solidophobic electrode will revolutionarily simplify the existing techniques for seawater electrolysis and increase the economic viability for seawater electrolysis.

9.
J Affect Disord ; 360: 15-25, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38801922

RESUMEN

OBJECTIVE: This study uses a two-sample Mendelian randomization (MR) analysis to delineate the causal influence of gut microbiota on the occurrence of irritable bowel syndrome (IBS), concurrently assessing the potential mediating function of depression within this framework. METHODS: Several two-sample MR methods were used to assess the causal repercussions of gut microbiota on the onset of both IBS and depression. Following this, gut microbiota and depression, which demonstrated notable causal associations, were integrated as exposure variables in a multivariable Mendelian randomization (MVMR) framework to construct a model encompassing gut microbiota, depression, and IBS. Mediation effects were assessed by examining the indirect pathway of gut microbiota → depression → IBS. RESULTS: Two-sample MR analysis unveiled a statistically significant causal association (P < 0.05) between specific bacterial group within the gut microbiota, notably p_Actinobacteria(OR = 0.829225), c_Clostridia(OR = 0.798897), s_Desulfovibrio_piger(OR = 1.163912), g_Streptococcus(OR = 1.132735), c_Actinobacteria(OR = 0.829224), and the onset of IBS. In the MVMR analysis, the relationship between depression and IBS was significant across Model 3, Model 7, Model 8, and Model 13 (P < 0.05). Assessment of mediation effects revealed that c_Clostridia and o_Clostridiales indirectly impacted IBS through depression, with masking effect ratios of 168.46 % and 168.44 %, respectively. CONCLUSION: These findings underscore a resilient causal association between the composition of gut microbiota and the initiation of IBS. Furthermore, depression serves as a mediator for particular groups of gut bacteria, thereby contributing to the development of IBS. These observations imply that interventions targeting mental health may potentially alleviate the risk of IBS onset attributable to adverse configurations of gut microbiota.


Asunto(s)
Depresión , Microbioma Gastrointestinal , Síndrome del Colon Irritable , Análisis de la Aleatorización Mendeliana , Síndrome del Colon Irritable/microbiología , Humanos , Depresión/microbiología
10.
J Inorg Biochem ; 257: 112599, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38749082

RESUMEN

The urgent global health problem of antimicrobial resistance (AMR) calls for the discovery of new antibiotics with innovative modes of action while considering the low toxicity to mammalian cells. This paper proposes a novel strategy for designing antibiotics with selective bacterial toxicity by exploiting the positional differences of electron transport chains (ETC) in bacterial and mammalian cells. The focus is on cytochrome c (cyt C) and its maturation system in E. coli. The catalytic oxidative activity of metallophthalocyanine (MPc), which have a distinctive M-N4 structure, is being investigated. Unlike previous applications based on light-activated reactive oxygen species (ROS) generation, this study exploits the ability of MPcs to oxidize Fe2+ to Fe3+ in cyt C and catalyze the formation of disulfide bonds between cysteine residues to interfere with cyt C maturation, disrupt the bacterial respiratory chain and selectively kills bacteria. In contrast, in mammalian cells, these MPcs are located in the lysosomes and cannot access the ETC in the mitochondria, thus achieving selective bacterial toxicity. Two MPcs that showed effective antibacterial activity in a wound infection model were identified. This study provides a valuable reference for the design of novel antibiotics based on M-N4-based metal complex molecules.


Asunto(s)
Antibacterianos , Escherichia coli , Indoles , Antibacterianos/farmacología , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Indoles/química , Indoles/farmacología , Animales , Citocromos c/metabolismo , Citocromos c/química , Isoindoles , Humanos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Ratones , Pruebas de Sensibilidad Microbiana , Especies Reactivas de Oxígeno/metabolismo , Oxidación-Reducción
11.
Adv Mater ; 36(32): e2404493, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38718355

RESUMEN

Optical waveguides fabricated in single crystals offer crucial passive/active optical components for photonic integrated circuits. Single crystals possess inherent advantages over their amorphous counterpart, such as lower optical losses in visible-to-mid-infrared band, larger peak emission cross-section, higher doping concentration. However, the writing of Type-I positive refractive index modified waveguides in single crystals using femtosecond laser technology presents significant challenges. Herein, this work introduces a novel femtosecond laser direct writing technique that combines slit-shaping with an immersion oil objective to fabricate low-loss Type-I waveguides in single crystals. This approach allows for precise control of waveguide shape, size, mode-field, and refractive index distribution, with a spatial resolution as high as 700 nm and a high positive refractive index variation on the order of 10-2, introducing new degrees of freedom to design and fabricate passive/active optical waveguide devices. As a proof-of-concept, this work successfully produces a 7 mm-long circular-shaped gain waveguide (≈10 µm in diameter) in an Er3+-doped YAG single crystal, exhibiting a propagation loss as low as 0.23 dB cm-1, a net gain of ≈3 dB and a polarization-insensitive character. The newly-developed technique is theoretically applicable to arbitrary single crystals, holding promising potential for various applications in integrated optics, optical communication, and photonic quantum circuits.

12.
Phytomedicine ; 129: 155612, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38669968

RESUMEN

BACKGROUND: Colorectal cancer (CRC) continues to be a major global health challenge, ranking as a top cause of cancer-related mortality. Alarmingly, the five-year survival rate for CRC patients hovers around a mere 10-30 %. The disruption of fibroblast growth factor receptor (FGFRs) signaling pathways is significantly implicated in the onset and advancement of CRC, presenting a promising target for therapeutic intervention in CRC management. Further investigation is essential to comprehensively elucidate FGFR1's function in CRC and to create potent therapies that specifically target FGFR1. PURPOSE: This study aims to demonstrate the oncogenic role of FGFR1 in colorectal cancer and to explore the potential of ß,ß-dimethylacrylalkannin (ß,ß-DMAA) as a therapeutic option to inhibit FGFR1. METHODS: In this research, we employed a comprehensive suite of techniques including tissue array, kinase profiling, computational docking, knockdown assay to predict and explore the inhibitor of FGFR1. Furthermore, we utilized kinase assay, pull-down, cell proliferation tests, and Patient derived xenograft (PDX) mouse models to further investigate a novel FGFR1 inhibitor and its impact on the growth of CRC. RESULTS: In our research, we discovered that FGFR1 protein is markedly upregulated in colorectal cancer tissues, suggesting a significant role in regulating cellular proliferation, particularly in patients with colorectal cancer. Furthermore, we conducted a computational docking, kinase profiling analysis, simulation and identified that ß,ß-DMAA could directly bind with FGFR1 within ATP binding pocket domain. Cell-based assays confirmed that ß,ß-DMAA effectively inhibited the proliferation of colon cancer cells and also triggered cell cycle arrest, apoptosis, and altered FGFR1-mediated signaling pathways. Moreover, ß,ß-DMAA effectively attenuated the development of PDX tumors in mice that were FGFR1-positive, with no notable toxicity observed. In summary, our study highlights the pivotal role of FGFR1 in colorectal cancer, suggesting that inhibiting FGFR1 activity could be a promising strategy for therapeutic intervention. We present strong evidence that targeting FGFR1 with ß,ß-DMAA is a viable approach for the management of colorectal cancer. Given its low toxicity and high efficacy, ß,ß-DMAA, as an FGFR1 inhibitor, warrants further investigation in clinical settings for the treatment of FGFR1-positive tumors.


Asunto(s)
Proliferación Celular , Neoplasias Colorrectales , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Animales , Femenino , Humanos , Ratones , Acrilamidas/farmacología , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Angew Chem Int Ed Engl ; 63(27): e202320014, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38598078

RESUMEN

Amino acids are the building blocks of proteins and are widely used as important ingredients for other nitrogen-containing molecules. Here, we report the sustainable production of amino acids from biomass-derived hydroxy acids with high activity under visible-light irradiation and mild conditions, using atomic ruthenium-promoted cadmium sulfide (Ru1/CdS). On a metal basis, the optimized Ru1/CdS exhibits a maximal alanine formation rate of 26.0 molAla ⋅ gRu -1 ⋅ h-1, which is 1.7 times and more than two orders of magnitude higher than that of its nanoparticle counterpart and the conventional thermocatalytic process, respectively. Integrated spectroscopic analysis and density functional theory calculations attribute the high performance of Ru1/CdS to the facilitated charge separation and O-H bond dissociation of the α-hydroxy group, here of lactic acid. The operando nuclear magnetic resonance further infers a unique "double activation" mechanism of both the CH-OH and CH3-CH-OH structures in lactic acid, which significantly accelerates its photocatalytic amination toward alanine.


Asunto(s)
Aminoácidos , Biomasa , Compuestos de Cadmio , Rutenio , Sulfuros , Sulfuros/química , Rutenio/química , Compuestos de Cadmio/química , Catálisis , Aminoácidos/química , Procesos Fotoquímicos , Teoría Funcional de la Densidad , Luz
14.
ACS Nano ; 18(13): 9403-9412, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38488193

RESUMEN

Diatomic-site catalysts (DASCs) inherit the excellent performance of single-atom catalysts (SACs) by utilizing two adjacent atomic metal species to achieve functional complementarity and synergistic effects that improve the carbon dioxide reduction reaction (CO2RR) and H2 evolution reaction (HER) kinetics. Herein, we report a method to further improve the catalytic efficiency of Pt by using Pt and Ru single atoms randomly anchored on a g-C3N4 surface, yielding partial Pt-Ru dimers. The synthesized catalyst exhibits extraordinary photocatalytic activity and stability in both the CO2RR and HER processes. In-depth experimentation, the pH-dependent chemical exchange saturation transfer (CEST) imaging nuclear magnetic resonance (NMR) method, and theoretical analyses reveal that the excellent performance is attributed to orbital coupling between the Pt atoms and the neighboring Ru atoms (mainly dxy and dxz), which decreases the orbital energy levels and weakens the bond strength with intermediates, resulting in improved CO2RR and HER performance. This study successfully applies the pH-dependent CEST imaging NMR method to catalytic reactions, and CO2 adsorption is directly observed using CEST 2D imaging maps. This work presents significant potential for a variety of catalytic reaction applications by systematically designing bimetallic dimers with higher activity and stability.

15.
ACS Nano ; 18(8): 6550-6557, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38353478

RESUMEN

Metal halide perovskite (MHP) structures that exhibit polarized photoluminescence (PL) have attracted significant interest in fabricating light field regulation elements for display, imaging, and information storage applications. We report a three-dimensional direct lithography of heterostructures for controllable polarized PL inside glass by laser-induced localized temperature engineering. The heterostructures consisted of oriented periodic structures (OPSs) and MHP nanocrystals, and the mechanism for hierarchical distribution of heterostructures was illustrated. The patterning of heterostructures for manipulable polarized PL can be used for information encryption, wave-plate, and polarized micro-LEDs.

16.
Front Artif Intell ; 7: 1299169, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38348210

RESUMEN

Accurate prediction of cattle weight is essential for enhancing the efficiency and sustainability of livestock management practices. However, conventional methods often involve labor-intensive procedures and lack instant and non-invasive solutions. This study proposed an intelligent weight prediction approach for cows based on semantic segmentation and Back Propagation (BP) neural network. The proposed semantic segmentation method leveraged a hybrid model which combined ResNet-101-D with the Squeeze-and-Excitation (SE) attention mechanism to obtain precise morphological features from cow images. The body size parameters and physical measurements were then used for training the regression-based machine learning models to estimate the weight of individual cattle. The comparative analysis methods revealed that the BP neural network achieved the best results with an MAE of 13.11 pounds and an RMSE of 22.73 pounds. By eliminating the need for physical contact, this approach not only improves animal welfare but also mitigates potential risks. The work addresses the specific needs of welfare farming and aims to promote animal welfare and advance the field of precision agriculture.

17.
Small ; 20(16): e2306226, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38037680

RESUMEN

It has been well-established that light-matter interactions, as manifested by diverse linear and nonlinear optical (NLO) processes, are mediated by real and virtual particles, such as electrons, phonons, and excitons. Polarons, often regarded as electrons dressed by phonons, are known to contribute to exotic behaviors of solids, from superconductivity to photocatalysis, while their role in materials' NLO response remains largely unexplored. Here, the NLO response mediated by polarons supported by a model ionic metal oxide, TiO2, is examined. It is observed that the formation of polaronic states within the bandgap results in a dramatic enhancement of NLO absorption coefficient by over 130 times for photon energies in the sub-bandgap regions, characterized by a 100 fs scale ultrafast response that is typical for thermalized electrons in metals. The ultrafast polaronic NLO response is then exploited for the development of all-optical switches for ultrafast pulse generation in near-infrared (NIR) fiber lasers and modulation of optical signal in the telecommunication band based on evanescent interaction on a planar waveguide chip. These results suggest that the polarons supported by dielectric ionic oxides can fill the gaps left by dielectric and metallic materials and serve as a novel platform for nonlinear photonic applications.

18.
J Affect Disord ; 346: 167-173, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-37949239

RESUMEN

BACKGROUND: The optimal multimorbidity measures for predicting disability trajectories are not universally agreed upon. We developed a multimorbidity index among middle-aged and older community-dwelling Chinese adults and compare its predictive ability of disability trajectories with other multimorbidity measures. METHODS: This study included 17,649 participants aged ≥50 years from the China Health and Retirement Longitudinal Survey 2011-2018. Two disability trajectory groups were estimated using the total disability score differences calculated between each follow-up visit and baseline. A weighted index was constructed using logistic regression models for disability trajectories based on the training set (70 %). The index and the condition count were used, along with the pattern identified by the latent class analysis to measure multimorbidity at baseline. Logistic regression models were used in the training set to examine associations between each multimorbidity measure and disability trajectories. C-statistics, integrated discrimination improvements, and net reclassification indices were applied to compare the performance of different multimorbidity measures in predicting disability trajectories in the testing set (30 %). RESULTS: In the newly developed multimorbidity index, the weights of the chronic conditions varied from 1.04 to 2.55. The multimorbidity index had a higher predictive performance than the condition count. The condition count performed better than the multimorbidity pattern in predicting disability trajectories. LIMITATION: Self-reported chronic conditions. CONCLUSIONS: The multimorbidity index may be considered an ideal measurement in predicting disability trajectories among middle-aged and older community-dwelling Chinese adults. The condition count is also suggested due to its simplicity and superior predictive performance.


Asunto(s)
Personas con Discapacidad , Multimorbilidad , Persona de Mediana Edad , Humanos , Anciano , Estudios Longitudinales , Vida Independiente , Enfermedad Crónica
19.
Opt Lett ; 49(1): 33-36, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134145

RESUMEN

High-gain materials and high-quality structures are the two main conditions that determine the amplification performance of optical waveguides. However, it has been hard to balance each other, to date. In this work, we demonstrate breakthroughs in both glass optical gain and optical waveguide structures. We propose a secondary melting dehydration technique that prepares high-quality Er3+-Yb3+ co-doped phosphate glass with low absorption loss. Additionally, we propose a femtosecond laser direct-writing technique that allows controlling the cross section, size, and mode field of waveguides written in glass with high accuracy, leveraging submicron-resolution multi-scan direct-writing optical waveguide technology, which is beneficial for reducing insertion loss. As a proof of concept demonstration, we designed and fabricated two kinds of waveguides, namely, LP01- and LP11-mode waveguides in the Er3+-Yb3+ co-doped phosphate glass, enabling insertion loss as low as 0.9 dB for a waveguide length of 2 mm. Remarkably, we successfully achieved an optical amplification for both the waveguides with a net gain of >7 dB and a net-gain coefficient of >3.5 dB/mm, which is approximately one order of magnitude larger than that in the Er3+-Yb3+ co-doped phosphate glass fabricated by the traditional melt-quenching method. This will open new avenues toward the development of integrated photonic chips.

20.
Clin Transl Sci ; 16(12): 2779-2790, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37932924

RESUMEN

Based on previous findings, collateral circulation in the brain is vital in mitigating cerebral ischemia's effects and influencing stroke risk. This retrospective study examined collateral circulation, admission ischemic stroke status, and long-term recurrence in patients with multiple craniocervical artery stenoses. Consecutive symptomatic internal carotid artery (ICA) stenosis patients from the First Affiliated Hospital of Soochow University were recruited. Baseline data including medical histories and neurological function at admission were collected. Imaging techniques assessed collateral compensative capacity. Multivariate logistic regression analysis was used to investigate the association between collateral circulation and case status. A total of 559 patients with symptomatic ICA stenosis were included, among whom 153 (27.4%) had concurrent moderate to severe vertebro-basilar artery (VBA) stenosis. Dizziness, weakness/numbness, and slurring of speech were the primary symptoms in all patients. Over 36 months, 71 (12.7%) patients experienced a recurrence of acute ischemic stroke (AIS). In multivariate analysis, collateral circulation was found to be negatively associated with AIS (regional leptomeningeal collateral [rLMC] scores: OR: 0.798, 95% CI: 0.743-0.857, p < 0.001; Tan scores: OR: 0.478, 95% CI: 0.336-0.679, p < 0.001). Meanwhile, the collateral circulation scores were significantly associated with the recurrence of AIS within 3 years (rLMC scores: OR: 0.926, 95% CI: 0.860-0.997, p = 0.042; Tan scores: OR: 0.467, 95% CI: 0.306-0.712, p < 0.001). Most associations remained significant in the subgroup of patients with VBA stenosis. Favorable collateral circulation in multiple craniocervical artery stenosis patients reduced long-term ischemic event recurrence. Stratifying treatment risks is essential for optimizing outcomes.


Asunto(s)
Estenosis Carotídea , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/etiología , Constricción Patológica , Estudios Retrospectivos , Circulación Colateral , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Arterias
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