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1.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612670

RESUMO

We aimed to identify serum exosomal microRNAs (miRNAs) associated with the transition from atrial fibrillation (AF) to sinus rhythm (SR) and investigate their potential as biomarkers for the early recurrence of AF within three months post-treatment. We collected blood samples from eight AF patients at Chang Gung Memorial Hospital in Taiwan both immediately before and within 14 days following rhythm control treatment. Exosomes were isolated from these samples, and small RNA sequencing was performed. Using DESeq2 analysis, we identified nine miRNAs (16-2-3p, 22-3p, 23a-3p, 23b-3p, 125a-5p, 328-3p, 423-5p, 504-5p, and 582-3p) associated with restoration to SR. Further analysis using the DIABLO model revealed a correlation between the decreased expression of miR-125a-5p and miR-328-3p and the early recurrence of AF. Furthermore, early recurrence is associated with a longer duration of AF, presumably indicating a more extensive state of underlying cardiac remodeling. In addition, the reads were mapped to mRNA sequences, leading to the identification of 14 mRNAs (AC005041.1, ARHGEF12, AMT, ANO8, BCL11A, DIO3OS, EIF4ENIF1, G2E3-AS1, HERC3, LARS, NT5E, PITX1, SLC16A12, and ZBTB21) associated with restoration to SR. Monitoring these serum exosomal miRNA and mRNA expression patterns may be beneficial for optimizing treatment outcomes in AF patients.


Assuntos
Fibrilação Atrial , Exossomos , MicroRNAs , Humanos , Fibrilação Atrial/genética , MicroRNAs/genética , Coração , Exossomos/genética , RNA Mensageiro , Anoctaminas
2.
Sci Rep ; 14(1): 6793, 2024 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514827

RESUMO

Virus diseases are a major production constraint for pumpkin. Recessive resistance to squash leaf curl China virus and tomato leaf curl New Delhi virus has been mapped in Cucurbita moschata (Duchesne ex Poir.) breeding line AVPU1426 to chromosomes 7 and 8, respectively. Molecular markers tightly associated with the resistance loci have been developed and were able to correctly predict resistance and susceptibility with an accuracy of 99% for squash leaf curl China virus resistance and 94.34% for tomato leaf curl New Delhi virus in F2 and back cross populations derived from the original resistance source AVPU1426. The markers associated with resistance are recommended for use in marker-assisted breeding.


Assuntos
Begomovirus , Cucurbita , Cucurbita/genética , Doenças das Plantas/genética , Melhoramento Vegetal , Begomovirus/genética , Biomarcadores , China
3.
Sports Biomech ; : 1-14, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38369902

RESUMO

This study aims to investigate the different ground reaction force (GRF) characteristics from different stride types. This study included 30 Taiwanese elite college and professional baseball pitchers. Each pitcher was classified into one of the following stride types: tall and fall (TF), dip and drive (DD), or mixed (MX). Our findings indicated that DD pitchers pressed their bodies forward earlier than TF pitchers. In contrast, the GRF of the pivot leg of TF pitchers increased slowly in the first half of the stride phase and continued to increase even after the stride leg touched the ground. This type of continuous pressing in TF was different from that in DD and MX pitchers, which decreased rapidly into the arm-cocking & acceleration phases. We conclude that the lower extremities were used differently by TF, DD and MX pitchers. This information could serve as a training guideline for coaches and pitchers to enhance training effectiveness, while simultaneously lowering injury risks.

4.
Otolaryngol Head Neck Surg ; 170(3): 952-961, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37997285

RESUMO

OBJECTIVE: In patients with obstructive sleep apnea (OSA), epiglottic collapse (EC) constitutes a major factor in the failure of continuous positive airway pressure therapy and uvulopalatopharyngoplasty. This study explored treatments that can improve EC in patients with OSA through drug-induced sleep endoscopy with target-controlled infusion (TCI-DISE). STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary center. METHODS: This study screened 352 OSA patients who underwent TCI-DISE between 2016 and 2022. Fifty-four patients with EC were included in the final analysis. EC severity was assessed multiple times through TCI-DISE with different interventions. RESULTS: The application of these interventions in patients with anteroposterior epiglottic collapse (apEC) led to a significant decrease in apEC severity from total to partial or no obstruction in 60.0% of patients by head rotation, in 53.6% by mouth closure, in 47.4% who received oral appliances (OA), and in 28.0% who received intermittent negative airway pressure (iNAP). With simultaneous head rotation, apEC severity decreased more significantly from total to partial or no obstruction in 77.8% of patients by mouth closure, in 70.3% who received OA, and in 68.0% who received iNAP. Lateral epiglottic collapse (latEC) severity decreased in 53.8% of patients after OA use and in 61.5% of patients with OA use and head rotation. CONCLUSION: This study identified head rotation with mouth closure as the most effective treatment for apEC through TCI-DISE. Patients with latEC had higher weight, apnea-hypopnea index, and body mass index compared with patients with apEC. OA use with head rotation appeared more effective in latEC through TCI-DISE.


Assuntos
Fenilglioxal/análogos & derivados , Apneia Obstrutiva do Sono , Sono , Humanos , Estudos Retrospectivos , Apneia Obstrutiva do Sono/cirurgia , Endoscopia
5.
Occup Ther Int ; 2023: 7281505, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38046620

RESUMO

Introduction: Occupational therapy (OT) educational programs are aimed at enrolling a diverse student population that is likely to succeed in the academic and fieldwork components of the program. Comprehending the array of factors that influence students' learning and academic and fieldwork success is important for university educators. This study investigated the existing literature on predictors of academic and fieldwork performance in OT students. Methods: The search process used in this review included screening, eligibility, and study quality. We searched the PubMed and Cochrane Library databases for literature published in the past 10 years (1 January 2012 to 30 March 2022). As a comprehensive search, the following keywords were used for abstract, title, and keywords sections: occupational therapy student, predictors, fieldwork, academic, academic success, academic performance, fieldwork success, and fieldwork performance. The Medical Education Research Study Quality Instrument was used to assess the quality of studies. Results: The systematic review retrieved 14 articles that met inclusion criteria. Most were cross-sectional studies, followed by cohort, retrospective analysis of secondary data, and exploratory studies. Four articles focused on academic success, eight focused on fieldwork success, and two explored both aspects. Promising predictors of academic performance included the admission grade point average and the student's approach to studying. Predictors of fieldwork performance included a graduate record examination score, emotional intelligence, and interpersonal relationships. Conclusion: This systematic review explores predictors of academic and fieldwork success in OT students, which provide opportunities to identify early the learning difficulties of students and assist educators to target modifiable predictors so they can provide high-quality education.


Assuntos
Desempenho Acadêmico , Terapia Ocupacional , Humanos , Terapia Ocupacional/educação , Estudos Retrospectivos , Estudantes/psicologia , Cognição
6.
ACS Appl Mater Interfaces ; 15(41): 48543-48550, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37792701

RESUMO

This study presents the utilization of MoS2 as a diffusion barrier for metal interconnects, in situ transmission electron microscopy (TEM) observations are employed for comprehensive understanding. The diffusion-blocking ability of MoS2 is discussed by the diffusion and phase transformation between Ru and Si via TEM diffraction and imaging. When the sample is heated to a high temperature such that MoS2 loses the ability to block the diffusion, Si diffuses through the MoS2 into the Ru layer, leading to the formation of Ru2Si3. Both multilayer and monolayer (1L) MoS2 exhibit exceptional diffusion-blocking ability up to 800 °C. Furthermore, plasma-treated 1L-MoS2 shows a slightly low diffusion-blocking temperature of 750 °C, while the dangling bonds in MoS2 improve the interfacial adhesion. These findings suggest that MoS2 holds great potential as a diffusion barrier for metal interconnects.

7.
Sensors (Basel) ; 23(16)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37631838

RESUMO

Autonomous robots heavily rely on simultaneous localization and mapping (SLAM) techniques and sensor data to create accurate maps of their surroundings. When multiple robots are employed to expedite exploration, the resulting maps often have varying coordinates and scales. To achieve a comprehensive global view, the utilization of map merging techniques becomes necessary. Previous studies have typically depended on extracting image features from maps to establish connections. However, it is important to note that maps of the same location can exhibit inconsistencies due to sensing errors. Additionally, robot-generated maps are commonly represented in an occupancy grid format, which limits the availability of features for extraction and matching. Therefore, feature extraction and matching play crucial roles in map merging, particularly when dealing with uncertain sensing data. In this study, we introduce a novel method that addresses image noise resulting from sensing errors and applies additional corrections before performing feature extraction. This approach allows for the collection of features from corresponding locations in different maps, facilitating the establishment of connections between different coordinate systems and enabling effective map merging. Evaluation results demonstrate the significant reduction of sensing errors during the image stitching process, thanks to the proposed image pre-processing technique.

9.
Theriogenology ; 208: 60-70, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37301167

RESUMO

Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) is a key regulator of sperm function and physiological metabolism. Metformin, an inexpensive and effective antioxidant, is known to play an important role in the activation of AMPK. Therefore metformin has potential to improve sperm cryopreservation. The aim of this study was to investigate the effect of metformin during semen cryopreservation of sheep and to find the most effective concentration in freezing extender. Semen were cryopreserved with extender containing different concentrations of metformin (0, 0.25, 0.5, 1.0, 2.0 and 4.0 mmol/L). Sperm motility, acrosome integrity and plasma membrane integrity were measured after semen freezing and thawing. All results showed that sperm quality was significantly increased in the 1.0 mmol/L metformin-treated group compared with the control group (P < 0.05). In addition, the study showed that metformin effectively reduced the content of malondialdehyde (MDA) and reactive oxygen species (ROS), and increased the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT) and total antioxidant capacity (T-AOC) of freeze-thawed sperm (P < 0.05). The optimal concentration of metformin was 1.0 mmol/L. Moreover, the results showed that AMPK was localized in the acrosome region, junction and midsection of sperm, and p-AMPK was distributed in the post-acrosomal region, junction and midsection. Western blot analysis indicated that 1.0 mmol/L metformin stimulated the phosphorylation of AMPK in sperm. Further results showed that 1.0 mmol/L metformin significantly increased the mitochondrial membrane potential (ΔΨm), ATP content, glucose uptake and lactate efflux of post-thawed sperm through the AMPK pathway, improved sperm quality, and increased the cleavage rate of in vitro fertilization (P < 0.05).


Assuntos
Proteínas Quinases Ativadas por AMP , Sêmen , Masculino , Animais , Ovinos , Antioxidantes/farmacologia , Motilidade dos Espermatozoides , Criopreservação/veterinária , Espermatozoides
10.
Biosensors (Basel) ; 13(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36671941

RESUMO

In photoacoustic (PA) imaging, tissue absorbs specific wavelengths of light. The absorbed energy results in thermal expansion that generates ultrasound waves that are reconstructed into images. Existing commercial PA imaging systems for preclinical brain imaging are limited by imprecise positioning capabilities and inflexible user interfaces. We introduce a new visible charge-coupled device (CCD) camera-guided photoacoustic imaging (ViCPAI) system that integrates an ultrasound (US) transducer and a data acquisition platform with a CCD camera for positioning. The CCD camera accurately positions the US probe at the measurement location. The programmable MATLAB-based platform has an intuitive user interface. In vitro carbon fiber and in vivo animal experiments were performed to investigate the precise positioning and imaging capabilities of the ViCPAI system. We demonstrated real-time capturing of bilateral cerebral hemodynamic changes during (1) forelimb electrical stimulation under normal conditions, (2) forelimb stimulation after right brain focal photothrombotic ischemia (PTI) stroke, and (3) progression of KCl-induced cortical spreading depression (CSD). The ViCPAI system accurately located target areas and achieved reproducible positioning, which is crucial in animal and clinical experiments. In animal experiments, the ViCPAI system was used to investigate bilateral cerebral cortex responses to left forelimb electrical stimulation before and after stroke, showing that the CBV and SO2 in the right primary somatosensory cortex of the forelimb (S1FL) region were significantly changed by left forelimb electrical stimulation before stroke. No CBV or SO2 changes were observed in the bilateral cortex in the S1FL area in response to left forelimb electrical stimulation after stroke. While monitoring CSD progression, the ViCPAI system accurately locates the S1FL area and returns to the same position after the probe moves, demonstrating reproducible positioning and reducing positioning errors. The ViCPAI system utilizes the real-time precise positioning capability of CCD cameras to overcome various challenges in preclinical and clinical studies.


Assuntos
Técnicas Fotoacústicas , Acidente Vascular Cerebral , Ratos , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Córtex Cerebral/fisiologia , Neuroimagem
11.
Mar Environ Res ; 185: 105892, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36689845

RESUMO

This paper presents a case study of red tide hazards around the Pearl River Estuary (PRE). Red tide hazards, meteorological data, and seawater monitoring data were collected from 1996 to 2020 at different locations around the PRE to investigate the internal and external factors influencing the occurrence of red tides. The enhancement of the assessment of estuarine trophic status (ASSETS) method enables us to evaluate the effects of meteorological factors and seawater eutrophication status on the red tide risk level. Using ASSETS, we established a framework for red tide risk assessment of the Pearl River Estuary. We analysed the external and internal factors causing the red tide based on meteorological data and seawater monitoring data in the PRE. The results show that the temperature was higher than the annual monthly average temperature of 1.265 °C, and east and north winds at velocities of 3-4 m/s could result in the formation of red tides. However, precipitation inhibits the formation of the red tide in PRE.


Assuntos
Proliferação Nociva de Algas , Rios , Estuários , China , Água do Mar , Monitoramento Ambiental
12.
Nat Immunol ; 24(2): 280-294, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36543960

RESUMO

T cell dysfunctionality prevents the clearance of chronic infections and cancer. Furthermore, epigenetic programming in dysfunctional CD8+ T cells limits their response to immunotherapies, including immune checkpoint blockade (ICB). However, it is unclear which upstream signals drive acquisition of dysfunctional epigenetic programs, and whether therapeutically targeting these signals can remodel terminally dysfunctional T cells to an ICB-responsive state. Here we innovate an in vitro model system of stable human T cell dysfunction and show that chronic TGFß1 signaling in posteffector CD8+ T cells accelerates their terminal dysfunction through stable epigenetic changes. Conversely, boosting bone morphogenetic protein (BMP) signaling while blocking TGFß1 preserved effector and memory programs in chronically stimulated human CD8+ T cells, inducing superior responses to tumors and synergizing the ICB responses during chronic viral infection. Thus, rebalancing TGFß1/BMP signals provides an exciting new approach to unleash dysfunctional CD8+ T cells and enhance T cell immunotherapies.


Assuntos
Linfócitos T CD8-Positivos , Viroses , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo
13.
Nanomaterials (Basel) ; 12(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36364594

RESUMO

Enhanced scattering from local surface plasmon resonance by light has attracted much attention due to its special applications in sensor, cell, and biological imaging . Here, we investigate the ratio of scattering to absorption in bimetallic three-layered nanoshells with different geometrical parameters using quasi-static theory. We show that the ratio of scattering to absorption strongly depends on the inner radius, shell thickness, middle dielectric function, and surrounding medium function. To gain insight into the effect of such geometrical parameters on the plasmonic scattering, we also provide a comparison between silver-dielectric-gold nanoshells and gold-dielectric-silver nanoshells. This work provides an alternative approach to analyze the optical properties of bimetallic three-layered nanoshells with potential applications in sensors and photo-detectors.

14.
Environ Pollut ; 314: 120254, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36152706

RESUMO

This study proposes a red tide risk assessment method based on intercriteria correlation (CRITIC), technique for order preference by similarity to an ideal solution (TOPSIS), assessment of estuarine trophic status (ASSETS) methods and Monte Carlo simulation (MCS) to calculate the probability of each risk level. The integrated TOPSIS-ASSETS method is used to calculate the risk levels of each year, where index weight is determined by CRITIC method. MCS method is employed to calculate the probability of each risk level. The results showed that level III to level V indicates high possibility of red tides in the case study area (Tolo Harbor). The highest risk rating was level V in 1988. The change of the risk level of red tide is consistent with the real situation of the occurrence of red tide. Another case of the east part of Skagerrak Strait shows that the results of this method are consistent with field situation. When there is an error between the evaluation results and the real situation, MCS can further suggest the probability of error in the evaluation results. Meanwhile, sensitivity analysis was used to test the performance of the evaluation model and two comparative methods. The results show that the proposed risk assessment method has better performance than other methods and can provide an effective risk evaluation for red tide management.


Assuntos
Proliferação Nociva de Algas , Método de Monte Carlo , Medição de Risco
15.
Front Bioeng Biotechnol ; 10: 910902, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910012

RESUMO

Multimodal imaging contrast agents for cancer that can not only perform diagnostic functions but also serve as tumor microenvironment-responsive biomaterials are encouraging. In this study, we report the design and fabrication of a novel enzyme-responsive T1 magnetic resonance imaging (MRI) contrast agent that can modulate oxygen in the tumor microenvironment via the catalytic conversion of H2O2 to O2. The T1 contrast agent is a core-shell nanoparticle that consists of manganese oxide and hyaluronic acid (HA)-conjugated mesoporous silica nanoparticle (HA-MnO@MSN). The salient features of the nanoparticle developed in this study are as follows: 1) HA serves as a targeting ligand for CD44-expressing cancer cells; 2) HA allows controlled access of water molecules to the MnO core via the digestion of enzyme hyaluronidase; 3) the generation of O2 bubbles in the tumor by consuming H2O2; and 4) the capability to increase the oxygen tension in the tumor. The r 1 relaxivity of HA-MnO@MSN was measured to be 1.29 mM-1s-1 at a magnetic field strength of 9.4 T. In vitro results demonstrated the ability of continuous oxygen evolution by HA-MnO@MSN. After intratumoral administration of HA-MnO@MSN to an HCT116 xenograft mouse model, T1 weighted MRI contrast was observed after 5 h postinjection and retained up to 48 h. In addition, in vivo photoacoustic imaging of HA-MnO@MSN demonstrated an increase in the tumor oxygen saturation over time after i. t. administration. Thus, the core-shell nanoparticles developed in this study could be helpful in tumor-targeted T1 MR imaging and oxygen modulation.

16.
Nanoscale ; 14(37): 13532-13541, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36004452

RESUMO

Sustainable energy strategies, particularly solar-to-hydrogen production, are anticipated to overcome the global reliance on fossil fuels. Thereby, materials enabling the production of green hydrogen from water and sunlight are continuously designed, e.g., ZnO nanostructures coated by gold sea-urchin-like nanoparticles, which employ the light-to-plasmon resonance to realize photoelectrochemical water splitting. But such light-to-plasmon resonance is strongly impacted by the size, the species, and the concentration of the metal nanoparticles coating on the ZnO nanoflower surfaces. Therefore, a precise prediction of the surface plasmon resonance is crucial to achieving an optimized nanoparticle fabrication of the desired light-to-plasmon resonance. To this end, we synthesized a substantial amount of metal (gold) nanoparticles of different sizes and species, which are further coated on ZnO nanoflowers. Subsequently, we utilized a genetic algorithm neural network (GANN) to obtain the synergistically trained model by considering the light-to-plasmon conversion efficiencies and fabrication parameters, such as multiple metal species, precursor concentrations, surfactant concentrations, linker concentrations, and coating times. In addition, we integrated into the model's training the data of nanoparticles due to their inherent complexity, which manifests the light-to-plasmon conversion efficiency far from the coupling state. Therefore, the trained model can guide us to obtain a rapid and automatic selection of fabrication parameters of the nanoparticles with the anticipated light-to-plasmon resonance, which is more efficient than an empirical selection. The capability of the method achieved in this work furthermore demonstrates a successful projection of the light-to-plasmon conversion efficiency and contributes to an efficient selection of the fabrication parameters leading to the anticipated properties.

17.
J Ethnopharmacol ; 296: 115431, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35700852

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Danhong injection (DHI), which is a Chinese clinical prescription consists of Radix et Rhizoma Salviae Miltiorrhizae (Salvia miltiorrhiza Bge., Labiatae, Danshen in Chinese) and Flos Carthami (Carthamus tinctorius L., Compositae, Honghua in Chinese)(Plant names have been checked with http://www.theplantlist.org on March 1st, 2022), has been mainly used in the clinical therapy of cardiovascular diseases, including hypertension in China for many years. AIM OF THE STUDY: Cardiovascular diseases (CVDs) are the major causes of death all around the world. Due to the various stimulation, a series of vasoconstrictor substances are secreted to regulate the vasoconstriction function and then change blood pressure. The representative substances leading to abnormal vasoconstriction include renin-angiotensin system, endothelin, vasopressin and adrenaline, which act on the corresponding receptors on vascular smooth muscle to constrict blood vessels. Finally, blood pressure increases, followed by a series of cardiovascular diseases, including hypertension. However, little is known about Danhong injection's specific vasodilating mechanisms and active substances. The aims of the study were to determine the vasodilating substances of Danhong injection and explain its molecular mechanism of vasodilation. MATERIALS AND METHODS: The effects of DHI and its active components on vascular tension were measured by myograph system in the aortic or mesenteric rings of mice. Based on this, the pharmacodynamic substances were analyzed and effective molecules were found. Combined with multiple types of vascular myograph experiments and network pharmacological analysis, the molecular pathway was preliminarily determined. With molecular biology experiments, it was verified that the relevant mechanisms were closely related to calcium-mediated vasoconstriction in smooth muscle cells. RESULTS: DHI could relax endothelium-removed aortic rings pre-constricted with PE and 3 possible active vasodilator substances, including salvianolic acid A, salvianolic acid B and danshensu, were screened out by network pharmacology and vascular myograph experiments, among which the effects of salvianolic acid A were dominant. Meanwhile, salvianolic acid A could dilate mesenteric artery in a pressure-dependent manner. Interestingly, salvianolic acid A could still relax the vascular rings under the stimulation of KCl and Bayk8644, two agonists of L-type calcium channel. By contrast, inhibitors of Kir, Kv, Katp and BKCa channels did not block the effect of salvianolic acid A on vasodilation. Salvianolic acid A alleviated Ca2+ transient, referring to changes of intracellular calcium, induced by PE, Bayk8644 and high K+ in the VSMCs. Salvianolic acid A could partially restore the vasodilation function of vascular smooth muscle damaged by AngII and ET-1 induced hypertension situation. CONCLUSIONS: Our results indicate that salvianolic acid A is the major vasodilator substance in DHI and the vasorelaxation pharmacology mechanism involved in inhibiting the L-type calcium channel signaling in smooth muscle cell. Hence, there are potential therapeutic effects of taking salvianolic acid A preparation which may be beneficial to protect cardiovascular system and reduce blood pressure.


Assuntos
Doenças Cardiovasculares , Hipertensão , Salvia miltiorrhiza , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil) , Animais , Artérias , Ácidos Cafeicos , Cálcio/metabolismo , Canais de Cálcio Tipo L , Medicamentos de Ervas Chinesas , Lactatos , Camundongos , Salvia miltiorrhiza/química , Vasodilatação , Vasodilatadores/farmacologia
18.
Biosens Bioelectron ; 211: 114339, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35588636

RESUMO

By D-arginine and L-arginine chiral peptides induced spin selectivity and Au NPs enhanced spin polarization, chiral peptides purification has been effectively simplified and the purification performance has raised from a mixture system. The angular momentums of light are operated by the polarizer and wave plates. Au NPs decorated ZnO nanorods electrodes are utilized to modulate the polarization of spintronic. Seed growth methods are for synthesizing spherical Au NPs. UV light reduction methods are for urchin-liked Au NPs. Au NPs are decorated on ZnO nanorods electrodes for rising photon to electron conversion efficiency and enhancing spin polarization rates by surface plasmon effect. From our results, photon to the electron conversion efficiency of ZnO nanorods electrodes has effectively enhanced by urchin-liked Au NPs decorating. Ultrahigh localized plasmon conversion efficiency as high as 60% was also obtained. Besides, density functional theory (DFT) calculations simulated the force on spintronic. Since the D-arginine and L-arginine are on Au substrate, DFT results demonstrate different angular momentum and spin polarization coupling. Along with urchin-liked Au NPs rising chiral induced spin polarization by surface plasmon resonance, the sensitivity of chiral arginine has been raised around 5000% from bare ZnO nanorods electrodes. The purification and separation time of a specific chiral arginine only needs 5 min.


Assuntos
Técnicas Biossensoriais , Óxido de Zinco , Arginina , Ouro , Peptídeos
19.
Food Chem ; 385: 132730, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35318180

RESUMO

In order to develop the tyrosinase inhibitors with potential application in food industry, a series of stilbene-hydroxypyridinone hybrids were prepared. Among these compounds, 1h was found to possess the most potent tyrosinase inhibitory effect on both monophenolase and diphenolase activities, with IC50 values of 2.72 µM and 15.86 µM, respectively. The inhibitory effect of 1h on monophenolase activity was 4.6 times that of kojic acid. An inhibition kinetic assay indicated that 1h was a mixed-type and reversible inhibitor. The copper-binding and reducing ability assays, molecular docking study, intrinsic and ANS-binding fluorescence assays indicated that copper coordination and reduction is likely to be the causative mechanism for 1h-induced inhibition on tyrosinase. The results of color measurement and browning index determination indicated that treatment with 1h retarded effectively the browning of freshly-cut apples during their storage. Meanwhile, PPO and POD activities in apple slices were found to be effectively inhibited.


Assuntos
Agaricales , Malus , Estilbenos , Cobre , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase
20.
J Sci Food Agric ; 102(9): 3817-3825, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34923627

RESUMO

BACKGROUND: Tyrosinase inhibitors find potential application in food, cosmetic and medicinal products, but most of the identified tyrosinase inhibitors are not suitable for practical use because of safety regulations or other problems. For the purpose of development of novel tyrosinase inhibitors that meet the requirement for practical application, a novel stilbene analogue (SA) was designed. RESULTS: SA was found to possess a potent inhibitory effect against both mono- and diphenolase activities of mushroom tyrosinase, with IC50 values of 1.56 and 7.15 µmol L-1 , respectively. Compared with a natural tyrosinase inhibitor - kojic acid - the anti-tyrosinase effect of SA was significantly improved. Analysis of inhibition kinetics indicated that SA was a reversible and competitive-noncompetitive mixed-type inhibitor. SA was also found to possess more potent antioxidant activities (DPPH, superoxide anion radical and hydroxyl radical scavenging ability) than those of kojic acid. Cell viability studies revealed that SA was non-toxic to two cell lines. Furthermore, an anti-browning test demonstrated that SA effectively delayed the blackening of shrimp. CONCLUSION: SA has potential as an anti-browning agent in foods. © 2021 Society of Chemical Industry.


Assuntos
Agaricales , Estilbenos , Agaricales/metabolismo , Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase , Estilbenos/farmacologia
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