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1.
Research (Wash D C) ; 7: 0412, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38979517

RESUMO

The combination of all-inorganic perovskites (PVSKs) and polymers allows for free-standing flexible optoelectronic devices. However, solubility difference of the PVSK precursors and concerns over the compatibility between polymer carriers and PVSKs imply a great challenge to incorporate different kinds of PVSKs into polymer matrices by the same manufacturing process. In this work, PVSK precursors are introduced into poly(2-hydroxyethyl acrylate) (PHEA) hydrogels in sequence, in which the PVSK-gel composites are achieved with full-color emissions by simply varying the precursor species. Moreover, it is found that CsBr has a higher interaction energy with the (111) plane of CsPbBr3 than the (110) plane; thus, the CsPbBr3 crystals with a shape of truncated cube and tetragon are observed during the CsPbBr3-Cs4PbBr6 phase transition over time. The PVSK-gel composites feature excellent bendability, elasticity, and stretchable deformation (tensile strain > 500%), which allows for 3D printing emissive customized stereoscopic architectures with shape-memory features.

2.
Aging Dis ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916732

RESUMO

Endothelial dysfunction and blood-brain barrier (BBB) leakage have been suggested as a fundamental role in the development of cerebral small vessel disease (SVD) pathology. However, the molecular and cellular mechanisms that link cerebral hypoxic hypoperfusion and BBB disruption remain elusive. Sphingosine-1-phosphate (S1P) regulates the BBB integrity by binding to its receptor isoform 1 (S1PR1) on endothelial cells. This study tested the hypothesis that hypoxic hypoperfusion triggers capillary endothelial S1PR1 disruption, which compromises BBB integrity and leads to SVD-related neuropathological changes, using a chronic hypoxic hypoperfusion model with BBB dysfunction. Spontaneously hypertensive rat stroke-prone underwent unilateral carotid artery occlusion (UCAO) followed by a Japanese permissive diet (JPD) for up to 9 weeks. Selective S1PR1 agonist SEW2871 was used to activate S1PR1. Significant progressive reduction of S1PR1 was detected in rat brains from 4 to 9 weeks following UCAO/JPD onset, which was also detected in cerebral vasculature in human SVD. S1PR1 activation by SEW2871 significantly reduced lesions in both white and grey matter and ameliorated cerebral blood flow. SEW2871 reversed the loss of endothelial S1PR1 and tight junction proteins, and significantly attenuated UCAO/JPD induced accumulation of neuronal phosphorylated tau. This protective role of SEW2871 is associated with promotion of Akt phosphorylation and inhibition of S1PR2/Erk1/2 activation. Our data suggest S1PR1 signalling as a potential molecular mechanistic basis that links hypoxic hypoperfusion with BBB damage in the neuropathological cascades in SVD. The reversal of BBB disruption through pharmacological intervention of S1PR1 signalling likely reveals a novel therapeutic target for SVD.

3.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38725292

RESUMO

The local field potential (LFP) is an extracellular electrical signal associated with neural ensemble input and dendritic signaling. Previous studies have linked gamma band oscillations of the LFP in cortical circuits to sensory stimuli encoding, attention, memory, and perception. Inconsistent results regarding gamma tuning for visual features were reported, but it remains unclear whether these discrepancies are due to variations in electrode properties. Specifically, the surface area and impedance of the electrode are important characteristics in LFP recording. To comprehensively address these issues, we conducted an electrophysiological study in the V1 region of lightly anesthetized mice using two types of electrodes: one with higher impedance (1 MΩ) and a sharp tip (10 µm), while the other had lower impedance (100 KΩ) but a thicker tip (200 µm). Our findings demonstrate that gamma oscillations acquired by sharp-tip electrodes were significantly stronger than those obtained from thick-tip electrodes. Regarding size tuning, most gamma power exhibited surround suppression at larger gratings when recorded from sharp-tip electrodes. However, the majority showed enhanced gamma power at larger gratings when recorded from thick-tip electrodes. Therefore, our study suggests that microelectrode parameters play a significant role in accurately recording gamma oscillations and responsive tuning to sensory stimuli.


Assuntos
Ritmo Gama , Camundongos Endogâmicos C57BL , Estimulação Luminosa , Córtex Visual Primário , Animais , Ritmo Gama/fisiologia , Camundongos , Estimulação Luminosa/métodos , Córtex Visual Primário/fisiologia , Masculino , Microeletrodos , Córtex Visual/fisiologia , Eletrodos
4.
Artigo em Inglês | MEDLINE | ID: mdl-38526893

RESUMO

View-based methods have demonstrated promising performance in 3D shape understanding. However, they tend to make strong assumptions about the relations between views or learn the multi-view correlations indirectly, which limits the flexibility of exploring inter-view correlations and the effectiveness of target tasks. To overcome the above problems, this paper investigates flexible organization and explicit correlation learning for multiple views. In particular, we propose to incorporate different views of a 3D shape into a permutation-invariant set, referred to as View Set, which removes rigid relation assumptions and facilitates adequate information exchange and fusion among views. Based on that, we devise a nimble Transformer model, named VSFormer, to explicitly capture pairwise and higher-order correlations of all elements in the set. Meanwhile, we theoretically reveal a natural correspondence between the Cartesian product of a view set and the correlation matrix in the attention mechanism, which supports our model design. Comprehensive experiments suggest that VSFormer has better flexibility, efficient inference efficiency and superior performance. Notably, VSFormer reaches state-of-the-art results on various 3d recognition datasets, including ModelNet40, ScanObjectNN and RGBD. It also establishes new records on the SHREC'17 retrieval benchmark. The code and datasets are available at https://github.com/auniquesun/VSFormer.

5.
Adv Mater ; 36(6): e2309890, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38011853

RESUMO

Pure-phase α-FAPbI3 quantum dots (QDs) are the focus of an increasing interest in photovoltaics due to their superior ambient stability, large absorption coefficient, and long charge-carrier lifetime. However, the trap states induced by the ligand-exchange process limit the photovoltaic performances. Here, a simple post treatment using methylamine thiocyanate is developed to reconstruct the FAPbI3 -QD film surface, in which a MAPbI3 capping layer with a thickness of 6.2 nm is formed on the film top. This planar perovskite heterojunction leads to a reduced density of trap-states, a decreased band gap, and a facilitated charge carrier transport. As a result, a record high power conversion efficiency (PCE) of 16.23% with negligible hysteresis is achieved for the FAPbI3 QD solar cell, and it retains over 90% of the initial PCE after being stored in ambient environment for 1000 h.

6.
Cancer Control ; 30: 10732748231177541, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37204026

RESUMO

BACKGROUND: This study aimed to develop a novel predictive nomogram to identify specific stage IB non-small cell lung cancer (NSCLC) populations who could benefit from adjuvant chemotherapy (ACT). METHOD: Stage IB NSCLC patients were included in the Surveillance, Epidemiology, and End Results (SEER) database and divided into the ACT and non-ACT groups. Then the methods of Kaplan-Meier analysis, propensity score matching (PSM), Least absolute shrink and selection operator (LASSO) regression, and multivariate logistic regression analyses were implemented. Finally, the predictive nomogram was constructed and validated. RESULTS: 9055 stage IB NSCLC patients were enrolled from the SEER database while 47 patients from Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University were identified as the external validation cohort. Of these patients, 1334 cases underwent ACT while the other 7721 patients didn't receive ACT. After PSM, the patients in the ACT group presented longer median overall survival (100 vs 82 months, P < .001). Among the ACT group, 482 (49.6%) patients achieving more prolonged overall survival than 82 months were regarded as the beneficiary population. Then the LASSO regression and multivariate logistic regression analyses were implemented. Finally, 8 predictors were selected for model construction, including age, gender, marital status, laterality, pathology, tumor size, regional nodes examined, and tumor size. The predictive nomogram demonstrated good discrimination in the training cohort (AUC = .781), internal validation cohort (AUC = .772), and external validation cohort (AUC = .851). And calibration curves indicated ideal consistency between the predicted and observed probabilities. Decision curve analysis presented a clinically useful model. CONCLUSION: The practical nomogram could guide treatment decision-making and select optimal ACT candidates among stage IB NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Quimioterapia Adjuvante , Neoplasias Pulmonares/tratamento farmacológico , Nomogramas
8.
Heliyon ; 8(11): e11583, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36406682

RESUMO

It has been a challenge to support the expansion of urban agriculture (UA) in cities due to its poor economic profitability. However, it is also hard to deny the increasing benefits of UA in improving the socio-environmental dimension of cities. Hence, in this review, different aspects of UA were examined to highlight its value beyond profitability such as social, health and well-being, disaster risk reduction, and environmental perspectives. A case study and relevant policies were analyzed to determine how policy makers can bridge the gap between current and future UA practices and sustainable development. Bridging these policy gaps can help the UA sector to sustainably grow and become successfully integrated in cities. Moreover, advancements in UA technologies and plant biotechnology were presented as potential solutions in increasing the future profitability of commercial UA. Consequently, as new UA-related technologies evolve, the multidisciplinary nature of UA and its changing identity from agriculture to digital technology, similarly require adaptive policies. These policies should maximize the potential of UA in contributing to resiliency and sustainability and incentivize the organic integration of UA in cities, while equally serving social justice.

9.
Biomed Chromatogr ; 36(11): e5453, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35853731

RESUMO

Aconiti Radix [Chuanwu (CW)] is widely used to treat chronic and intractable diseases due to its remarkable curative effect. CW has been combined with honey for thousands of years to reduce toxicity and enhance efficacy. This study first determined the compatibility mechanism of CW with honey using a comparative pharmacokinetic concept. We developed and validated a simple, sensitive, specific, and accurate UHPLC-MS/MS method to simultaneously determine five Aconitum alkaloids in rat plasma after the oral administration of CW decoction and CW-honey concentrated solution. Pharmacokinetic parameters were significantly different between the two groups (P < 0.01 and P < 0.05). Compared with the CW group, Cmax and AUC0 → t decreased in the CW-honey group for three diester-diterpenoid alkaloids (hypaconitine, mesaconitine, and aconitine); Tmax and T1/2 were prolonged. However, Cmax and AUC0 → t increased in the CW-honey group for two monoester-diterpenoid alkaloids (benzoylaconine and benzoylmesaconine); Tmax was shortened, and T1/2 was prolonged. These findings suggest that honey affected the pharmacokinetic behaviors of five Aconitum alkaloids. We speculate that the detoxification and synergism of honey might result from reducing the toxicity of diester-diterpenoid alkaloids and promoting the biological activity of monoester-diterpenoid alkaloids in vivo. This study provides a theoretical basis for the clinical use of CW combined with honey.


Assuntos
Aconitum , Alcaloides , Diterpenos , Medicamentos de Ervas Chinesas , Mel , Aconitina , Animais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Ratos , Espectrometria de Massas em Tandem/métodos
10.
Artigo em Inglês | MEDLINE | ID: mdl-35682150

RESUMO

Student commuting is an important part of urban travel demand and private car commuting plays an important role in urban traffic, especially in areas near schools. Since parents, especially the parents of elementary and junior high school students, prefer to drive rather than take public transport, there will be a negative effect on traffic management. To address the challenge, a simulation model is established based on schools' surrounding regions to analyze traffic status. Specifically, the model focuses on urban construction and transportation near the entrance of schools and neighborhoods. In addition, four variable parameters consisting of the directional hourly volume, the parking demand of delivery vehicles, the distance between the school and intersection, and the average parking time for pick-up vehicles are set as influence factors, while traffic efficiency, energy consumption, and pollutant emissions are considered as the evaluation criteria of our model. Extensive simulated experiments show that comparing different scenarios, the traffic state of schools' surrounding areas can achieve much better performance when the distance between entrances and intersections is 400 m under the 1000 pcu/h condition. This research can provide a scientific basis for school regional traffic management and organization optimization.


Assuntos
Instituições Acadêmicas , Meios de Transporte , Humanos , Estudantes , Caminhada
11.
Carbohydr Res ; 511: 108478, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34801925

RESUMO

α-Glucosidase is a promising target for the treatment of diabetes. Drug repurposing can increase the chances of discovering an active inhibitor. Therefore, this study aimed to identify potential α-glucosidase inhibitor using drug repurposing and in silico strategies. We identified critical amino acid residues of the three α-glucosidase proteins. Based on cross molecular docking studies of three α-glucosidase proteins and drugs in the FDA database, we screened hits with the favorable binding affinities and modes targeting the three proteins. Subsequently, an in vitro activity assay showed that raloxifene was an excellent inhibitor of α-glucosidase. Moreover, molecular dynamics simulations of raloxifene and three proteins were performed to assess the stability of the protein-hit systems in physiological conditions and clarify protein-hit interactions. We also performed the binding free energy calculation, Hirshfeld surface and alanine scanning mutagenesis analyses. These results demonstrated that binding between raloxifene and the three proteins was stable, and the critical amino acid residues of the three proteins formed stable contacts with raloxifene. The molecular mechanisms agree well with its activity, reinforcing that raloxifene is a candidate α-glucosidase inhibitor. Our study smoothes the path for the development of novel a-glucosidase inhibitors with high efficacy and low toxicity for the treatment of diabetes.


Assuntos
Reposicionamento de Medicamentos , Inibidores de Glicosídeo Hidrolases , Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Cloridrato de Raloxifeno/farmacologia , alfa-Glucosidases/metabolismo
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