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1.
J Am Chem Soc ; 146(13): 8820-8825, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38518245

RESUMEN

This study presents a global strategy for the transsulfuration of intracellular thiols (RSH) to persulfides (RSSH). Thiiranes comprising fluorenyl/diphenyl and malonate ester moieties directly convert intercellular RSH to low-molecular-weight RSSH in cells. The efficiency of transsulfuration is determined by counting the number of olefins produced as byproducts, providing ratiometric signals for the corresponding persulfide production. Specifically, the direct and rapid protein S-persulfidation by thiirane is validated. Thiiranes are expected to play a crucial role in the study of sulfur signaling.

2.
Small ; 20(33): e2401080, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38566553

RESUMEN

Non-fullerene acceptors (NFAs) significantly enhance photovoltaic performance in organic solar cells (OSCs) using halogenated solvents and additives. However, these solvents are environmentally detrimental and unsuitable for industrial-scale production, and the issue of OSCs' poor long-term stability persists. This report introduces eight asymmetric NFAs (IPCnF-BBO-IC2F, IPCnF-BBO-IC2Cl, IPCnCl-BBO-IC2F, and IPCnCl-BBO-IC2Cl, where n = 1 and 2). These NFAs comprise a 12,13-bis(2-butyloctyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2'',3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno-[3,2-b]indole (BBO) core. One end of the core attaches to a mono- or di-halogenated 9H-indeno[1,2-b]pyrazine-2,3-dicarbonitrile (IPC) end group (IPC1F, IPC1Cl, IPC2F, or IPC2Cl), while the other end connects to a 2-(5,6-dihalo-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (IC) end group (IC2F or IC2Cl). The optical and electronic properties of these NFAs can be finely tuned by controlling the number of halogen atoms. Crucially, these NFAs demonstrate excellent compatibility with PM6 even in o-xylene, facilitating the production of additive-free OSCs. The di-halogenated IPC-based NFAs outperform their mono-halogenated counterparts in photovoltaic performance within OSCs. Remarkably, the di-halogenated IPC-based NFAs maintain 94‒98% of their initial PCEs over 2000 h in air without encapsulation, indicating superior long-term device stability. These findings imply that the integration of di-halogenated IPCs in asymmetric NFA design offers a promising route to efficient, stable OSCs manufactured through environmentally friendly processes.

3.
Small ; 20(33): e2312120, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38558528

RESUMEN

The tunable properties of 2D transition-metal dichalcogenide (TMDs) materials are extensively investigated for high-performance and wavelength-tunable optoelectronic applications. However, the precise modification of large-scale systems for practical optoelectronic applications remains a challenge. In this study, a wafer-scale atomic assembly process to produce 2D multinary (binary, ternary, and quaternary) TMDs for broadband photodetection is demonstrated. The large-area growth of homogeneous MoS2, Ni0.06Mo0.26S0.68, and Ni0.1Mo0.9S1.79Se0.21 is carried out using a succinct coating of the single-source precursor and subsequent thermal decomposition combined with thermal evaporation of the chalcogen powder. The optoelectrical properties of the multinary TMDs are dependent on the combination of heteroatoms. The maximum photoresponsivity of the MoS2-, Ni0.06Mo0.26S0.68-, and Ni0.1Mo0.9S1.79Se0.21-based photodetectors is 3.51 × 10-4, 1.48, and 0.9 A W-1 for 532 nm and 0.063, 0.42, and 1.4 A W-1 for 1064 nm, respectively. The devices exhibited excellent photoelectrical properties, which is highly beneficial for visible and near-infrared (NIR) photodetection.

4.
J Nurs Scholarsh ; 56(4): 606-620, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38380588

RESUMEN

INTRODUCTION: The emergence of novel infectious diseases has amplified the urgent need for effective prevention strategies, especially ones targeting vulnerable populations such as children. Factors such as the high incidence of both emerging and existing infectious diseases, delays in vaccinations, and routine exposure in communal settings heighten children's susceptibility to infections. Despite this pressing need, a comprehensive exploration of research trends in this domain remains lacking. This study aims to address this gap by employing text mining and modeling techniques to conduct a comprehensive analysis of the existing literature, thereby identifying emerging research trends in infectious disease prevention among children. METHODS: A cross-sectional text mining approach was adopted, focusing on journal articles published between January 1, 2003, and August 31, 2022. These articles, related to infectious disease prevention in children, were sourced from databases such as PubMed, CINAHL, MEDLINE (Ovid), Scopus, and Korean RISS. The data underwent preprocessing using the Natural Language Toolkit (NLTK) in Python, with a semantic network analysis and topic modeling conducted using R software. RESULTS: The final dataset comprised 509 journal articles extracted from multiple databases. The study began with a word frequency analysis to pinpoint relevant themes, subsequently visualized through a word cloud. Dominant terms encompassed "vaccination," "adolescent," "infant," "parent," "family," "school," "country," "household," "community," "HIV," "HPV," "COVID-19," "influenza," and "diarrhea." The semantic analysis identified "age" as a key term across infection, control, and intervention discussions. Notably, the relationship between "hand" and "handwashing" was prominent, especially in educational contexts linked with "school" and "absence." Latent Dirichlet Allocation (LDA) topic modeling further delineated seven topics related to infectious disease prevention for children, encompassing (1) educational programs, (2) vaccination efforts, (3) family-level responses, (4) care for immunocompromised individuals, (5) country-specific responses, (6) school-based strategies, and (7) persistent threats from established infectious diseases. CONCLUSION: The study emphasizes the indispensable role of personalized interventions tailored for various child demographics, highlighting the pivotal contributions of both parental guidance and school participation. CLINICAL RELEVANCE: The study provides insights into the complex public health challenges associated with preventing and managing infectious diseases in children. The insights derived could inform the formulation of evidence-based public health policies, steering practical interventions and fostering interdisciplinary synergy for holistic prevention strategies.


Asunto(s)
Minería de Datos , Humanos , Niño , Estudios Transversales , Enfermedades Transmisibles/epidemiología , Salud Global/estadística & datos numéricos , Control de Enfermedades Transmisibles/métodos
5.
Vet Ophthalmol ; 27(2): 170-176, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38071419

RESUMEN

OBJECTIVE: To describe the hyperproliferation of Elschnig pearl-type posterior capsule opacification and concurrent uveitis in two canine eyes after phacoemulsification, followed by spontaneous resolution of the Elschnig pearls. ANIMAL STUDIED: A 10-year-old castrated male Spitz (Case 1) and a 4-year-old spayed female Bichon Frise (Case 2). PROCEDURE: Elschnig pearls proliferating beyond the anterior capsulotomy site were observed in the right eye 10 months after bilateral diabetic cataract surgery (Case 1) and 7 months after unilateral cataract surgery (Case 2). In both cases, hyperproliferation occurred where the anterior capsule did not overlap with the intraocular lens (IOL), and was accompanied by aqueous flare. In Case 1, the pearls extended from the anterior capsule and adhered to the iris, causing focal posterior synechia. No other possible causes of uveitis were apparent. RESULTS: Initially, uveitis severity improved after the administration of topical and systemic anti-inflammatory drugs. However, uveitis recurred when the dosage of anti-inflammatory treatment was reduced. The Elschnig pearls underwent morphological changes throughout the follow-up period. In both cases, the pearls beyond the anterior capsulotomy resolved spontaneously after 5 months. Only a few pearls remained between the IOL and posterior capsule, and no recurrence of pearl proliferation was observed at the last follow-up. CONCLUSIONS: To the best of our knowledge, this is the first report of spontaneous Elschnig pearl regression in dogs. Lens-induced uveitis (LIU) may have been caused by anterior chamber hyperproliferative pearls. LIU associated with hyperproliferative pearls may be managed with appropriate anti-inflammatory treatment and monitoring.


Asunto(s)
Opacificación Capsular , Catarata , Enfermedades de los Perros , Cápsula del Cristalino , Lentes Intraoculares , Facoemulsificación , Uveítis , Masculino , Perros , Femenino , Animales , Opacificación Capsular/veterinaria , Opacificación Capsular/cirugía , Implantación de Lentes Intraoculares/veterinaria , Remisión Espontánea , Complicaciones Posoperatorias/veterinaria , Catarata/etiología , Catarata/veterinaria , Lentes Intraoculares/efectos adversos , Facoemulsificación/veterinaria , Facoemulsificación/efectos adversos , Antiinflamatorios , Uveítis/complicaciones , Uveítis/veterinaria , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/cirugía
6.
J Pediatr Nurs ; 75: 72-79, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38103460

RESUMEN

PURPOSE: The psycho-emotional symptom experiences and health-related factors that influence the quality of life of adolescents with Moyamoya disease are still not fully understood. The aim of this study is to identify the daily physical and accompanying psychological symptom experiences of such adolescents, and to examine how health-related factors contribute to their quality of life. DESIGN AND METHOD: This study employed a descriptive cross-sectional research design. Data on a total of 134 adolescents with Moyamoya disease was analyzed in order to develop a path analysis. Data were collected from October 2019 to January 2021 in South Korea. The theory of salutogenesis was employed in order to develop a hypothetical model for this path analysis. Participants were given a self-reporting questionnaire. Descriptive analysis and path analysis were conducted based on the results. RESULTS: Adolescents with Moyamoya disease experienced several negative emotions simultaneously, regardless of the severity of their physical symptoms. The path analysis revealed that stress, a sense of coherence, behavior, and the support of friends were significant contributors to adolescents' quality of life. CONCLUSIONS: Adolescents with Moyamoya disease have multifaceted symptom experiences in their daily lives. To enhance their quality of life, it is crucial to provide support that can help strengthen their capacity for stress management and enhance their sense of coherence. PRACTICAL IMPLICATIONS: This study provides evidence that nurses should offer anticipatory information to adolescents with Moyamoya disease regarding the symptoms they will frequently encounter, and develop interventions to enhance their quality of life.


Asunto(s)
Enfermedad de Moyamoya , Calidad de Vida , Humanos , Adolescente , Calidad de Vida/psicología , Estudios Transversales , Emociones
7.
Eur J Neurosci ; 57(9): 1466-1480, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36970752

RESUMEN

Traumatic spinal cord injury (SCI) causes secondary damage in injured and adjacent regions due to temporal deprivation of oxygen and energy supply. Peroxisome proliferator-activated receptor γ (PPARγ) is known to regulate cell survival mechanisms such as hypoxia, oxidative stress, inflammation and energy homeostasis in various tissues. Thus, PPARγ has the potential to show neuroprotective properties. However, the role of endogenous spinal PPARγ in SCI is not well established. In this study, under isoflurane inhalation, a 10-g rod was freely dropped onto the exposed spinal cord after T10 laminectomy using a New York University impactor in male Sprague-Dawley rats. Cellular localization of spinal PPARγ, locomotor function and mRNA levels of various genes including NFκB-targeted pro-inflammatory mediators after intrathecal administration of PPARγ antagonists, agonists or vehicles in SCI rats were then analysed. In both sham and SCI rats, spinal PPARγ was presented in neurons but not in microglia or astrocytes. Inhibition of PPARγ induced IκB activation and increased mRNA levels of pro-inflammatory mediators. It also suppressed recovery of locomotor function with myelin-related gene expression in SCI rats. However, a PPARγ agonist showed no beneficial effects on the locomotor performances of SCI rats, although it further increased the protein expression of PPARγ. In conclusion, endogenous PPARγ has a role in anti-inflammation after SCI. Inhibition of PPARγ might have a negative influence on motor function recovery through accelerated neuroinflammation. Nonetheless, exogenous PPARγ activation does not appear to effectively help with functional improvement after SCI.


Asunto(s)
PPAR gamma , Traumatismos de la Médula Espinal , Ratas , Masculino , Animales , PPAR gamma/metabolismo , Ratas Sprague-Dawley , Médula Espinal/metabolismo , Neuronas/metabolismo , Mediadores de Inflamación , ARN Mensajero/metabolismo , Recuperación de la Función
8.
Plant Cell ; 32(4): 1081-1101, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32086363

RESUMEN

Nonsense-mediated mRNA decay (NMD), an mRNA quality control process, is thought to function in plant immunity. A subset of fully spliced (FS) transcripts of Arabidopsis (Arabidopsis thaliana) resistance (R) genes are upregulated during bacterial infection. Here, we report that 81.2% and 65.1% of FS natural TIR-NBS-LRR (TNL) and CC-NBS-LRR transcripts, respectively, retain characteristics of NMD regulation, as their transcript levels could be controlled posttranscriptionally. Both bacterial infection and the perception of bacteria by pattern recognition receptors initiated the destruction of core NMD factors UP-FRAMESHIFT1 (UPF1), UPF2, and UPF3 in Arabidopsis within 30 min of inoculation via the independent ubiquitination of UPF1 and UPF3 and their degradation via the 26S proteasome pathway. The induction of UPF1 and UPF3 ubiquitination was delayed in mitogen-activated protein kinase3 (mpk3) and mpk6, but not in salicylic acid-signaling mutants, during the early immune response. Finally, previously uncharacterized TNL-type R transcripts accumulated in upf mutants and conferred disease resistance to infection with a virulent Pseudomonas strain in plants. Our findings demonstrate that NMD is one of the main regulatory processes through which PRRs fine-tune R transcript levels to reduce fitness costs and achieve effective immunity.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/inmunología , Degradación de ARNm Mediada por Codón sin Sentido/genética , Moléculas de Patrón Molecular Asociado a Patógenos/metabolismo , Inmunidad de la Planta , Proteolisis , Arabidopsis/microbiología , Proteínas de Arabidopsis/genética , Autoinmunidad/genética , Regulación de la Expresión Génica de las Plantas , Sistema de Señalización de MAP Quinasas , Mutación/genética , Pseudomonas/patogenicidad , Estabilidad del ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ubiquitinación
9.
J Org Chem ; 88(13): 9381-9387, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37184952

RESUMEN

A 14-membered cyclic compound (3) containing amide, amino, and carbamate groups, which was serendipitously obtained in the oily residue after the separation of 4-benzyl-1,4,7,10-tetraazacyldododecane-2,6-dione (2a) and 4,16-dibenzyl-1,4,7,10,13,16,19,22-octaazacyclo-tetracosane-2,6,14,18-tetraone (2b), is reported. The structure of 3 is formally a CO2 insertion between positions 3 and 4 of the 12-membered ring in 2a. The CO2 insertion was confirmed in the synthesis of diethyl 2,2'-(benzylazanediyl)diacetate (1) by the reaction of benzylamine with ethyl bromoacetate using K2CO3 as the base. In addition, the selective synthesis of 3 and ethyl N-benzyl-N-((2-ethoxy-2-oxoethoxy)carbonyl)glycinate (5) and their kinetic behavior are reported. The reaction of 5 with triethylenetetramine afforded a 17-membered macrocycle (7), which was obtained in an 18% yield. Compounds 6 and 8 were prepared from 3 and 7 by introducing benzyl groups to improve their solubility in organic solvents. Titration experiments using 1H NMR showed that both 6 and 8 exhibit Li+ selectivity.


Asunto(s)
Amidas , Carbamatos , Dióxido de Carbono , Espectroscopía de Resonancia Magnética , Esqueleto
10.
Inorg Chem ; 62(5): 2058-2064, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36662552

RESUMEN

In the supramolecule area, the fabrication of a new concept called polyrotaxanes or poly-pseudo-rotaxanes remains challenging. We herein report the formation of a poly-pseudo-rotaxane in which the same salt-type guest serves both linking and threading in the resulting structure. The combination of A1/A2-thiopyridyl pillar[5]arene (L) and silver(I) trifluoroacetate in CHCl3/CH3OH afforded a one-dimensional (1D) poly-pseudo-rotaxane. In this structure, to our surprise, the AgCF3CO2 guest not only links the di-armed L ligands via an infinite -L-Ag-L-Ag- arrangement but also threads into a pillar[5]arene cavity in a dimer form, (AgCF3CO2)2. In contrast, the same reaction in CH2Cl2/CH3OH yielded a simple 1D coordination polymer because an included CH2Cl2 molecule in the pillar[5]arene cavity prevents the threading of the silver(I) trifluoroacetate guest. Comparative 1H- and 19F-NMR studies support the solvent-dependent poly-pseudo-rotaxane formation at a lower concentration of L.

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