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1.
Org Lett ; 26(39): 8217-8221, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39311758

RESUMEN

A Norrish-Yang photocyclization reaction has been applied to regio- and stereoselective construction of the ABCDE pentacyclic motif of natural product phainanoids. The observed substrate conformation control implicates this powerful reaction could be applied to the construction of structurally diverse natural product scaffolds.

2.
Talanta ; 281: 126858, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39260248

RESUMEN

Amyloid-ß (Aß) species (Aß fibrils and Aß plaques), as one of the typical pathological markers of Alzheimer's disease (AD), plays a crucial role in AD diagnosis. Currently, some near-infrared I (NIR I) Aß probes have been reported in AD diagnosis. However, they still face challenges such as strong background interference and the lack of effective probe design. In this study, we propose molecular design strategy that incorporates CN group and amphiphilic modulation to synthesize a series of amphiphilic NIR I Aß probes, surpassing the commercial probe ThT and ThS. Theoretical calculations indicate that these probes exhibit stronger interaction with amino acid residues in the cavities of Aß. Notably, the probes containing CN group display the ability of binding two distinct sites of Aß, which dramatically enhanced the affinity to Aß species. Furthermore, these probes exhibit minimal fluorescence in aqueous solution and offer ultra-high signal-to-noise ratio (SNR) for in vitro labeling, even in wash-free samples. Finally, the optimal probe DM-V2CN-PYC3 was utilized for in vivo imaging of AD mice, demonstrating its rapid penetration through the blood-brain barrier and labelling to Aß species. Moreover, it enabled long-term monitoring for a duration of 120 min. These results highlight the enhanced affinity and superior performance of the designed NIR I Aß probe for AD diagnosis. The molecular design strategy of CN and amphiphilic modulation presents a promising avenue for the development Aß probes with low background in vivo/in vitro imaging for Aß species.

3.
J Colloid Interface Sci ; 677(Pt A): 863-872, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39126804

RESUMEN

Solar-driven photo-thermal dry reforming of methane (DRM) is an environmentally friendly production route for high-value-added chemicals. However, the lack of thorough understanding of the mechanism for photo-thermal reaction has limited its further development. Here, we systematically investigated the mechanism of photo-thermal DRM reaction with the representative of Ru/CeO2 catalyst. Through in situ DRIFTs and transient experiments, comprehensive investigation into the reaction steps and their reactive sites in the process of DRM reaction were conducted. Besides, the excitation and migration direction of photo-electron was determined by ISI-XPS experiments, and the change of surface defect structure induced by light was characterized by ISI-EPR experiments. Based on the above results, the photo-enhancement effect on each micro-reaction step was determined. This study provides a theoretical basis for the industrialization of photo-thermal DRM reaction and its development of catalysts.

4.
ACS Appl Mater Interfaces ; 16(36): 48320-48328, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39207886

RESUMEN

The large-sized perovskite single-crystal sheet (SCS) serves as the ideal research platform for perovskite photodetectors due to its outstanding carrier photophysics, pronounced geometric aspect ratio, and ultrahigh material utilization rate. However, its performance in flexible device applications is relatively lackluster due to the rigid and brittle nature of the three-dimensional cubic lattices. In this work, the indium tin oxide (ITO)-based multimillimeter-sized MAPbBr3 SCS is transformed into MAPbI3 SCS via ion exchange strategy. Significantly, we proposed and implemented a polymer-controlled transfer strategy─utilizing the dichloromethane (DCM) solution of poly(methyl methacrylate) (PMMA)─to nondestructively transfer the whole perovskite SCS off the ITO substrates and subsequently adhere it onto a flexible polyethylene terephthalate (PET) substrate of interdigital electrode, thereby fabricating a lateral-structured photodetector with a PMMA-SCS-Au-PET multilayer configuration. The tight self-encapsulation between the top PMMA membrane and the bottom PET substrate imparts excellent waterproof stability and concurrently excellent mechanical flexibility to these devices; additionally, the MAPbI3 device exhibits comprehensively superior performance to the MAPbBr3 one. This work represents a proactive attempt and exploration of the high-performance advancement of large-sized SCS photodetectors, undoubtedly introducing novel momentum and solutions to this domain.

5.
Zhongguo Zhong Yao Za Zhi ; 49(11): 2853-2862, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39041144

RESUMEN

China cultivates characteristic resource plant Zingiber officinale for both medicine and food use, with a long history of cultivation, production, and application. With the continuous excavation of the health and skin care values of ginger products due to scientific and technological progress, the scale expansion and quality improvement of the ginger industry have been effectively promoted, forming an industrial cluster with rich germplasm resources and diverse product categories represented by the north and south regions of China, and China has been developed as the biggest producer and exporter of raw materials and processed products of ginger.The present situation of ginger germplasm resources, ginger production, market price, and quality control of ginger products was reviewed in this paper. According to data from the Food and Agriculture Organization of the United Nations(FAO), United Nations International Trade Database, Chinese Network for Ginger Trade, and China Industry Information Network, the market fluctuation and trend of ginger products in China and abroad were discussed, and the current development and utilization of Chinese and international ginger industries were analyzed. In addition, through the research group's field investigation of the main producing area of ginger in China, analysis and prediction were made, and measures to improve the quality and efficiency of ginger industry use were put forward,so as to offer experience for relevant departments to study and formulate the development plan and production layout of ginger industry,help practitioners in ginger industry to cope with challenges, and provide a reference for promoting the quality and efficiency of ginger industry and high-quality development.


Asunto(s)
Zingiber officinale , Zingiber officinale/química , Zingiber officinale/crecimiento & desarrollo , China , Control de Calidad , Medicamentos Herbarios Chinos/normas , Humanos
7.
Chem Biodivers ; 21(5): e202400210, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38433548

RESUMEN

Currently, natural products are one of the priceless options for finding novel chemical pharmaceutical entities. Ellipticine is a naturally occurring alkaloid isolated from the leaves of Ochrosia elliptica Labill. Ellipticine and its derivatives are characterized by multiple biological activities. The purpose of this review was to provide a critical and systematic assessment of ellipticine and its derivatives as bioactive molecules over the last 60 years. Publications focused mainly on the total synthesis of alkaloids of this type without any evaluation of bioactivity have been excluded. We have reviewed papers dealing with the synthesis, bioactivity evaluation and mechanism of action of ellipticine and its derivatives. It was found that ellipticine and its derivatives showed cytotoxicity, antimicrobial ability, and anti-inflammatory activity, among which cytotoxicity toward cancer cell lines was the most investigated aspect. The inhibition of DNA topoisomerase II was the most relevant mechanism for cytotoxicity. The PI3K/AKT pathway, p53 pathway, and MAPK pathway were also closely related to the antiproliferative ability of these compounds. In addition, the structure-activity relationship was deduced, and future prospects were outlined. We are confident that these findings will lay a scientific foundation for ellipticine-based drug development, especially for anticancer agents.


Asunto(s)
Elipticinas , Elipticinas/farmacología , Elipticinas/química , Humanos , Relación Estructura-Actividad , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Proliferación Celular/efectos de los fármacos , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Estructura Molecular , Animales , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación
8.
Alzheimers Dement ; 20(4): 2497-2507, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38332543

RESUMEN

INTRODUCTION: We tested the association of brain artery diameters with dementia and stroke risk in three distinct population-based studies using conventional T2-weighted brain magnetic resonance imaging (MRI) images. METHODS: We included 8420 adults > 40 years old from three longitudinal population-based studies with brain MRI scans. We estimated and meta-analyzed the hazard ratios (HRs) of the brain and carotids and basilar diameters associated with dementia and stroke. RESULT: Overall and carotid artery diameters > 95th percentile increased the risk for dementia by 1.74 (95% confidence interval [CI], 1.13-2.68) and 1.48 (95% CI, 1.12-1.96) fold, respectively. For stroke, meta-analyses yielded HRs of 1.59 (95% CI, 1.04-2.42) for overall arteries and 2.11 (95% CI, 1.45-3.08) for basilar artery diameters > 95th percentile. DISCUSSION: Individuals with dilated brain arteries are at higher risk for dementia and stroke, across distinct populations. Our findings underline the potential value of T2-weighted brain MRI-based brain diameter assessment in estimating the risk of dementia and stroke.


Asunto(s)
Demencia , Accidente Cerebrovascular , Adulto , Humanos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/complicaciones , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Arteria Basilar , Demencia/diagnóstico por imagen , Demencia/epidemiología , Demencia/complicaciones , Factores de Riesgo
9.
Scand J Gastroenterol ; 59(5): 518-523, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38343278

RESUMEN

Reflux hypersensitivity (RH) is a subtype of gastroesophageal reflux disease. The Rome IV criteria separated RH from the original nonerosive reflux disease subgroup and classified it as a new functional oesophageal disease. Recently, the pathogenesis of RH has become the focus of research. According to the latest research reports, upregulation of acid-sensitive receptors, distribution of calcitonin gene-related peptide-positive nerve fibres, and psychiatric comorbidity have key roles in the pathogenesis of RH. This work reviews the latest findings regarding RH mechanisms.


Asunto(s)
Reflujo Gastroesofágico , Humanos , Reflujo Gastroesofágico/fisiopatología , Péptido Relacionado con Gen de Calcitonina/metabolismo
10.
Nat Commun ; 15(1): 1677, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395971

RESUMEN

Efficient upconversion electroluminescence is highly desirable for a broad range of optoelectronic applications, yet to date, it has been reported only for ensemble systems, while the upconversion electroluminescence efficiency remains very low for single-molecule emitters. Here we report on the observation of anomalously bright single-molecule upconversion electroluminescence, with emission efficiencies improved by more than one order of magnitude over previous studies, and even stronger than normal-bias electroluminescence. Intuitively, the improvement is achieved via engineering the energy-level alignments at the molecule-substrate interface so as to activate an efficient spin-triplet mediated upconversion electroluminescence mechanism that only involves pure carrier injection steps. We further validate the intuitive picture with the construction of delicate electroluminescence diagrams for the excitation of single-molecule electroluminescence, allowing to readily identify the prerequisite conditions for producing efficient upconversion electroluminescence. These findings provide deep insights into the microscopic mechanism of single-molecule upconversion electroluminescence and organic electroluminescence in general.

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