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1.
Anal Chem ; 96(26): 10686-10695, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38885608

RESUMO

Exploiting the multiple properties of nanozymes for the multimode lateral flow assay (LFA) is urgently required to improve the accuracy and versatility. Herein, we developed a novel plasmonic Au nanostar@PtOs nanocluster (Au@PtOs) as a multimode signal tag for LFA detection. Based on the PtOs bimetallic nanocluster doping strategy, Au@PtOs can indicate both excellent SERS enhancement and nanozyme catalytic activity. Meanwhile, Au@PtOs displays a better photothermal effect than that of Au nanostars. Therefore, catalytic colorimetric/SERS/temperature three-mode signals can be read out based on the Au@PtOs nanocomposite. The Au@PtOs was combined with LFA and applied for breast cancer exosome detection. The detection limit for the colorimetric/SERS/temperature mode was 2.6 × 103/4.1 × 101/4.6 × 102 exosomes/µL, respectively, which was much superior to the common Au nanoparticles LFA (∼105 exosomes/µL). Moreover, based on the fingerprint molecular recognition ability of the SERS mode, exosome phenotypes derived from different breast cancer cell lines can be discriminated easily. Based on the convenient visual colorimetric mode and sensitive SERS/temperature quantitative modes, Au@PtOs driven LFA can satisfy the requirements of accurate and flexible multimodal sensing in different application scenarios.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Colorimetria , Exossomos , Ouro , Análise Espectral Raman , Humanos , Ouro/química , Exossomos/química , Técnicas Biossensoriais/métodos , Neoplasias da Mama/diagnóstico , Nanopartículas Metálicas/química , Platina/química , Linhagem Celular Tumoral , Limite de Detecção , Feminino
2.
Dalton Trans ; 53(11): 5084-5088, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38375913

RESUMO

The development of low-cost, high-efficiency, and stable electrocatalysts for the alkaline hydrogen evolution reaction (HER) is a key challenge because the alkaline HER kinetics is slowed by an additional water dissociation step. Herein, we report an interfacial engineering strategy for polyoxometalate (POM)-stabilized nickel (Ni) quantum dots decorated on the surface of porous titanium mesh (POMs-Ni@PTM) for high-rate and stable alkaline hydrogen production. Benefiting from the strong interfacial interactions among POMs, Ni atoms, and PTM substrates, as well as unique POM-Ni quantum dot structures, the optimized POMs-Ni@PTM electrocatalyst exhibits a remarkable alkaline HER performance with an overpotential (η10) of 30.1 mV to reach a current density of 10 mA cm-2, which is much better than those of bare Ni decorated porous titanium mesh (Ni@PTM) (η10 = 171.1 mV) and POM decorated porous titanium mesh (POMs@PTM) electrocatalysts (η10 = 493.6 mV), comparable to that of the commercial 20 wt% platinum/carbon (20% Pt/C) electrocatalyst (η10 = 20 mV). Moreover, the optimized POMs-Ni@PTM electrocatalyst demonstrates excellent stability under continuous alkaline water-splitting at a current density of ∼100 mA cm-2 for 100 h, demonstrating great potential for its practical application.

3.
Sci Rep ; 14(1): 74, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168759

RESUMO

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a neurotoxin that can cause gastrointestinal ulcers by affecting dopamine levels. Therefore, MPTP has been considered a toxic substance that causes gastric ulcer disease in experimental animals. In this study, tree shrews were used as the animal model of gastric mucosa injury, and MPTP was intraperitoneally injected at a lower MPTP dosage 2 mg/kg/day for 13 weeks, while tree shrews were not injected as the control group. Under the light microscope, local congestion or diffuse bleeding points of gastric mucosa and multiple redness and swelling bleeding symptoms on the inner wall were observed in the treatment group, as well as immune cell infiltration was found in HE staining, but no such phenomenon was observed in the control group. In order to explore the molecular basis of changes in MPTP induced gastric mucosa injury, the transcriptome and proteome data of gastric mucosa were analyzed. We observed significant differences in mRNA and protein expression levels under the influence of MPTP. The changes in mRNA and proteins are related to increased immune infiltration, cellular processes and angiogenesis. More differentially expressed genes play a role in immune function, especially the candidate genes RPL4 and ANXA1 with significant signal and core role. There are also differentially expressed genes that play a role in mucosal injury and shedding, especially candidate genes GAST and DDC with certain signaling and corresponding functions. Understanding the factors and molecular basis that affect the expression of related genes is crucial for coping with Emotionality gastric mucosa injury disease and developing new treatment methods to establish the ability to resist disease.


Assuntos
Tupaia , Tupaiidae , Animais , Tupaia/genética , Musaranhos/genética , Proteômica , Análise de Sequência de RNA , RNA Mensageiro , China , Estômago
4.
Neuropharmacology ; 239: 109691, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37625690

RESUMO

Dysfunctional glutamatergic neurotransmission contributes importantly to the pathophysiology of depression. However, the underlying neural mechanisms of glutamatergic dysfunction remain poorly understood. Here, we employed chronic unpredictable mild stress (CUMS) to induce depression-like behavior in male mice and to assess the alterations of glutamatergic system within the ventromedial prefrontal cortex (vmPFC). Male mice subjected to CUMS showed an increase in levels of glutamate content, synaptosomal GluN2B-NMDA receptors (GluN2B-NMDARs) and phosphorylated synaptosomal associated protein 25 KD of Ser187 (pSer187-SNAP25), which is involved in synaptic vesicular fusion processes in the vmPFC. Downregulation of pSer187-SNAP25 via the TAT-S187 fusion peptide efficiently alleviated CUMS-induced depressive-like behaviors in male mice by reversing the increase of glutamate content and synaptosomal GluN2B-NMDARs. These findings demonstrated a critical role for pSer187-SNAP25-mediated glutamatergic dysfunction in CUMS-induced depressive-like behaviors, suggesting the potential of pS187-SNAP25 inhibitors for further investigation on depression management.


Assuntos
Córtex Pré-Frontal , Transmissão Sináptica , Masculino , Animais , Camundongos , Proteína 25 Associada a Sinaptossoma , Regulação para Baixo , Ácido Glutâmico
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(4): 782-787, 2023 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-37545074

RESUMO

Objective: To prepare the hydrogel coating on the surfaces of nasogastric tubes and to evaluate its effect on the insertion of nasogastric tubes in a rabbit model. Methods: The polyacrylamide (PAAm) hydrogel coating was prepared by UV-induced free radical polymerization. The morphology of the PAAm coating and its interfacial bonding with the silicone rubber substrates of nasogastric tubes were observed with scanning electron microscope. The composition of the coating was analyzed by Fourier transform infrared (FTIR) spectrometer and X-ray photoelectron spectrometer (XPS). The water absorption power and stability of the coating were measured by the weighing method. Water contact angle meter was used to measure the wettability of the coating and tribometer was used to determine the friction coefficient of the silicone rubber substrates before and after the modification. The cytotoxicity of the coating on L929 murine fibroblast cell line was explored with CCK-8 assay after 24-h coculturing of the L929 cell line with silicone rubber substrates before and after modification. An animal model of nasogastric tube insertion in New Zealand rabbits was used to evaluate the effect of the lubrication coating by assessing the insertion time and nasal damage. Results: In this study, PAAm hydrogel coating was prepared and constructed on the surface of silicone rubber nasogastric tubes. The coating, with a three-dimensional network structure, showed strong interfacial bonding with silicone rubber substrates. The appearance of amino and carbonyl groups indicated that the PAAm hydrogel coating was grafted on the surfaces of nasogastric tubes. Before the modification, the silicone rubber substrate essentially did not absorb much water, whereas, after the modification, the silicone rubber substrate showed significant improvement of as much as 2.9% in water absorption. After sonication for 90 min, the weight loss rate was only 0.15%. Compared with pristine nasogastric tubes, the water contact angle of the modified nasogastric tubes was reduced from 111.9°±2.2° to 58.9°±1.5° ( t=22.59, P<0.05). In addition, the friction coefficient of silicone rubber nasogastric tubes decreased by 69.3% from 0.378±0.05 to 0.116±0.004 ( t=42.80, P<0.05) after modification. Moreover, there was no significant difference in the cytocompatibility between L929 cells cocultured with pristine nasogastric tube and those cocultured with modified nasogastric tube. The animal experiment of nasogastric tube insertion showed that the insertion time of the modified nasogastric tubes was reduced from (41.6±7.8) s to (12.4±2.9) s ( t=8.509, P<0.05). Laryngoscopy revealed that the PAAm hydrogel coating significantly reduced the mucosal damage caused by the insertion of nasogastric tubes. Conclusion: In this study, PAAm hydrogel coating with strong interfacial bonding was prepared on the surface of silicone rubber nasogastric tubes. The coating has excellent hydrophilic lubrication property and cytocompatibility, effectively shortens the insertion time, and reduces the damage caused by nasogastric tube insertion.


Assuntos
Hidrogéis , Elastômeros de Silicone , Camundongos , Animais , Coelhos , Elastômeros de Silicone/química , Molhabilidade , Água
6.
Artigo em Inglês | MEDLINE | ID: mdl-36430064

RESUMO

BACKGROUND: Bacteria are readily nourished in airtight environments with high humidity, such as storage cabinets, clothing closets, and corners, where ventilation is normally low and humidity is high. OBJECTIVES: We characterized the role of humidity and ventilation in bacterial growth and genus distribution at different temperatures (26 °C and 34 °C). METHODS: Fresh pork, which was used as the substrate for bacterial culture, was placed in storage cabinets. Bacterial growth and genera distribution on the surface of pork placed in a storage cabinet under different temperatures (26 °C and 34 °C); relative humidity levels (RH: 50%, 70%, 90%); and ventilation conditions (no ventilation and low, medium, and high levels of ventilation) were assessed by rDNA sequencing. RESULTS: Increased ventilation and reduced humidity significantly decreased bacterial growth at 26 °C and 34 °C. The contribution of increased ventilation to the reduction in bacterial growth exceeded that of decreased humidity. Ventilation had the greatest effect on reducing bacterial growth compared to the unventilated conditions at 70% RH. At 34 °C, medium and high levels of ventilation were required to reduce bacterial growth. High temperatures greatly increased bacterial growth, but ventilation could reduce the degree of this increase.


Assuntos
Respiração , Ventilação , Umidade , Temperatura , Bactérias/genética
8.
Indoor Air ; 31(2): 440-453, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32979003

RESUMO

This study comprehensively investigated the impact of indoor carbon dioxide (CO2 ) concentration on sleep quality. Three experimental conditions (800, 1900, 3000 ppm) were created in chambers decorated as bedroom and other environmental parameters that may influence the sleep quality were under strict control. Sleep quality of 12 subjects (6 men and 6 women) was monitored for 54 consecutive days through sleep quality questionnaire and physiological measures. Both subjective and physiological results showed that sleep quality decreased significantly with the increase of CO2 concentration, and the comprehensive questionnaire score at 3000 ppm was only 80.8% of that at 800 ppm. A linear positive correlation was found between sleep onset latency (SOL) and CO2 concentration, while a linear negative correlation occurred between slow-wave sleep (SWS) and CO2 concentration. In addition, in the same sleep environment, men had higher subjective questionnaire scores after wake-up, longer SWS and shorter SOL, which lead to a better sleep quality compared with women, and there was a significant gender difference in sleep quality at 800 ppm (P < .05).


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Dióxido de Carbono/análise , Sono/fisiologia , Adulto , Feminino , Humanos , Masculino
9.
Indoor Air ; 30(2): 198-212, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31845405

RESUMO

This paper reviews the published literature on indoor thermal environment and air quality in Chinese-style residential kitchens (CRKs). The paper first discusses typical characteristics of CRKs, including kitchen layout, cooking methods, and ventilation systems used. Next, the paper describes the current state of the indoor thermal environment and air quality in CRKs. Finally, this paper summarizes measures to control and improve the environment inside CRKs. The results indicate that the indoor environment of CRKs is too hot in summer and exhibits a large vertical temperature difference. No appropriate model was available for accurately evaluating the thermal environment in CRKs. At the same time, CRKs are highly polluted by COx, NOx, TVOC, and particulate matter (PM). Although existing exhaust hoods could improve the indoor environment to some extent, the use of a combined exhaust, make-up air, and air-conditioning system should be considered to provide a comfortable and healthy environment in CRKs.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Culinária , Monitoramento Ambiental , Temperatura , Ar Condicionado , Poluentes Atmosféricos , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , China , Habitação , Humanos , Material Particulado/análise , Ventilação
10.
Phytother Res ; 32(8): 1501-1510, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29732634

RESUMO

Berberine, an isoquinoline alkaloid, is demonstrated to have a variety of pharmacologic effects. Widely used as nonprescription drug for diarrhea, berberine has also broadened its applications in therapies of cardiovascular diseases, diabetes mellitus, tumor, and so forth. However, researches about berberine's protective effects on nervous system are still so insufficient that clinical uses cannot popularize and underlying molecules mechanisms are confused and incomplete. Well-known pathways such as Pl3K/Akt/Bcl-2 pathway, Nrf2/HO-1 pathway, and MAPK signaling pathway help berberine to protect neurons through antiapoptotic, antioxidative, and anti-inflammatory activities. New hypotheses have been raised consistently to explore more possible ways of berberine preventing nerves from injuries as attention on its neuroprotective properties is increasing. Therefore, this review is trying to analyze these mechanisms, which actually play roles in neuronal disease models such as brain ischemia, Alzheimer's disease, and experimental autoimmune encephalomyelitis. Much more understanding about how berberine mediates these pathways provides novel insights into the clinical treatment of neurological disorders.


Assuntos
Berberina/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer/tratamento farmacológico , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Humanos , Transdução de Sinais/efeitos dos fármacos
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