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1.
Int J Obes (Lond) ; 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341506

RESUMO

OBJECTIVE: Fatty acids play a critical role in the proper functioning of the brain. This study investigated the effects of a high-fat (HF) diet on brain fatty acid profiles of offspring exposed to maternal gestational diabetes mellitus (GDM). METHODS: Insulin receptor antagonist (S961) and HF diet were used to establish the GDM animal model. Brain fatty acid profiles of the offspring mice were measured by gas chromatography at weaning and adulthood. Protein expressions of the fatty acid transport pathway Wnt3/ß-catenin and the target protein major facilitator superfamily domain-containing 2a (MFSD2a) were measured in the offspring brain by Western blot. RESULTS: Maternal GDM increased the body weight of male offspring (P < 0.05). In weaning offspring, factorial analysis showed that maternal GDM increased the monounsaturated fatty acid (MUFA) percentage of the weaning offspring's brain (P < 0.05). Maternal GDM decreased offspring brain arachidonic acid (AA), but HF diet increased brain linoleic acid (LA) (P < 0.05). Maternal GDM and HF diet reduced offspring brain docosahexaenoic acid (DHA), and the male offspring had higher DHA than the female offspring (P < 0.05). In adult offspring, factorial analysis showed that HF diet increased brain MUFA in offspring, and male offspring had higher brain MUFA than female offspring (P < 0.05). The HF diet increased brain LA in the offspring. Male offspring had higher level of AA than female offspring (P < 0.05). HF diet reduced DHA in the brains of female offspring. The brain protein expression of ß-catenin and MFSD2a in both weaning and adult female offspring was lower in the HF + GDM group than in the CON group (P < 0.05). CONCLUSIONS: Maternal GDM increased the susceptibility of male offspring to HF diet-induced obesity. HF diet-induced adverse brain fatty acid profiles in both male and female offspring exposed to GDM.

2.
Adv Healthc Mater ; 13(5): e2302480, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38063347

RESUMO

Single-atom (SA) nanoparticles exhibit considerable potential in terms of photothermal properties for bactericidal applications. Nevertheless, the restricted efficacy of their targeted and controlled antibacterial activity has hindered their practical implementation. This study aims to overcome this obstacle by employing chemical modifications to tailor SAs, thereby achieving targeted and light-controlled antimicrobial effects. By conducting atomic-level modifications on palladium SAs using glutathione (GSH) and mercaptophenylboronic acid (MBA), their superior targeted binding capabilities toward Escherichia coli cells are demonstrated, surpassing those of SAs modified with cysteine (Cys). Moreover, these modified SAs effectively inhibit wound bacteria proliferation and promote wound healing in rats, without inducing noticeable toxicity to major organs under 808 nm laser irradiation. This study highlights the significance of chemical engineering in tailoring the antibacterial properties of SA nanoparticles, opening avenues for combating bacterial infections and advancing nanoparticle-based therapies.


Assuntos
Anti-Infecciosos , Nanopartículas , Ratos , Animais , Nanopartículas/química , Antibacterianos/química
3.
J Enzyme Inhib Med Chem ; 39(1): 2295241, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38134358

RESUMO

Colorectal cancer (CRC) is one of the most common cancers worldwide. Nowadays, owing to the complex mechanism of tumorigenesis, simultaneous inhibition of multiple targets is an important anticancer strategy. Recent studies have demonstrated receptor tyrosine kinase AXL (AXL) and histone deacetylase 2 (HDAC2) are closely associated with colorectal cancer. Herein, we identified five hit compounds concurrently targeting AXL and HDAC2 using virtual screening. Inhibitory experiments revealed these hit compounds potently inhibited AXL and HDAC2 in the nanomolar range. Among them, Hit-3 showed the strongest inhibitory effects which were better than that of the positive control groups. Additionally, MD assays showed that Hit-3 could bind stably to the AXL and HDAC2 active pockets. Further MTT assays demonstrated that Hit-3 showed potent anti-proliferative activity. Most importantly, Hit-3 exhibited significant in vivo antitumor efficacy in xenograft models. Collectively, this study is the first discovery of dual-targeting AXL/HDAC2 inhibitors for colorectal cancer treatment.


Assuntos
Neoplasias Colorretais , Simulação de Dinâmica Molecular , Humanos , Simulação de Acoplamento Molecular , Farmacóforo , Histona Desacetilase 2/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Detecção Precoce de Câncer , Neoplasias Colorretais/tratamento farmacológico
4.
J Med Chem ; 66(23): 16187-16200, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38093696

RESUMO

Dual inhibition of tubulin and neuropilin-1 (NRP1) may become an effective method for cancer treatment by simultaneously killing tumor cells and inhibiting tumor angiogenesis. Herein, we identified dual tubulin/NRP1-targeting inhibitor TN-2, which exhibited good inhibitory activity against both tubulin polymerization (IC50 = 0.71 ± 0.03 µM) and NRP1 (IC50 = 0.85 ± 0.04 µM). Importantly, it significantly inhibited the viability of several human prostate tumor cell lines. Further mechanism studies indicated that TN-2 could inhibit tubulin polymerization and cause G2/M arrest, thereby inducing cell apoptosis. It could also suppress cell tube formation, migration, and invasion. Moreover, TN-2 showed obvious antitumor effects on the PC-3 cell-derived xenograft model with negligible side effects and good pharmacokinetic profiles. These data demonstrate that TN-2 could be a promising dual-target chemotherapeutic agent for the treatment of prostate cancer.


Assuntos
Antineoplásicos , Tubulina (Proteína) , Humanos , Linhagem Celular Tumoral , Tubulina (Proteína)/metabolismo , Neuropilina-1 , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Apoptose , Farmacóforo , Proliferação de Células , Pontos de Checagem da Fase G2 do Ciclo Celular , Moduladores de Tubulina/farmacologia , Moduladores de Tubulina/uso terapêutico , Moduladores de Tubulina/química , Polimerização , Relação Estrutura-Atividade
5.
Ultrason Sonochem ; 101: 106658, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913593

RESUMO

The simultaneous extraction of crocin and geniposide from gardenia fruits (Gardenia jasminoides Ellis) was performed by integrating natural deep eutectic solvents (NADES) and ultrasound-assisted extraction (UAE). Among the eight kinds of NADES screened, choline chloride-1,2-propylene glycol was the most suitable extractant. The probe-type ultrasound-assisted NADES extraction system (pr-UAE-NADES) demonstrated higher extraction efficiency compared with plate-type ultrasound-assisted NADES extraction system (pl-UAE-NADES). Orthogonal experimental design and a modified multi-index synthetic weighted scoring method were adopted to optimize pr-UAE-NADES extraction process. The optimal extraction conditions that had a maximum synthetic weighted score of 29.46 were determined to be 25 °C for extraction temperature, 600 W for ultrasonic power, 20 min for extraction time, and 25% (w/w) for water content in NADES, leading to the maximum yields (7.39 ± 0.20 mg/g and 57.99 ± 0.91 mg/g, respectively) of crocin and geniposide. Thirty-three compounds including iridoids, carotenoids, phenolic acids, flavonoids, and triterpenes in the NADES extract were identified by LC-Q-TOF-MS2 coupled with a feature-based molecular networking workflow. The kinetics evaluation of the conjugated dienes generation on Cu2+-induced low density lipoprotein (LDL) oxidation via the four-parameter logistic regression model showed that crocin increased the lag time of LDL oxidation in a concentration-dependent manner (15 µg/mL, 30 µg/mL, 45 µg/mL) by 12.66%, 35.44%, and 73.42%, respectively. The quantitative determination for fluorescence properties alteration of the apolipoprotein B-100 exhibited that crocin effectively inhibited the fluorescence quenching of tryptophan residues and the modification of lysine residues caused by reactive aldehydes and malondialdehydes. The pr-UAE-NADES showed significant efficiency toward the simultaneous extraction of crocin and geniposide from gardenia fruits. And this study demonstrates the potential utility of gardenia fruits in developing anti-atherogenic functional food.


Assuntos
Solventes Eutéticos Profundos , Gardenia , Gardenia/química , Frutas/química , Iridoides/farmacologia , Iridoides/análise , Carotenoides/farmacologia , Carotenoides/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Solventes
6.
Nutrients ; 15(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37960172

RESUMO

This study aimed to explore the effects and mechanisms of maternal gestational diabetes mellitus (GDM) and selenium (Se) deficiency on the growth and glucose metabolism of offspring. Female C57BL/6J mice were divided into four groups as follows: a control group, a GDM group, a Se deficiency group, and a GDM with Se deficiency group. GDM animal models were established via S961. Pregnant mice fed their offspring until weaning. Then, offspring continued to be fed with a basic diet until adulthood. Body weight and fasting blood glucose were measured weekly. Se content, oxidative stress indicators, and the protein expression of the PI3K/Akt signaling pathway were detected. GDM increased susceptibility to obesity in lactating offspring, with gender differences observed in adult offspring. The effect of Se deficiency on SOD activity only appeared in female offspring during adulthood but was shown in male offspring during weaning though it disappeared during adulthood. GDM and Se deficiency increased the risk of abnormal glucose metabolism in female offspring from weaning to adulthood but gradually decreased in male offspring. The influence on the expression of PI3K/Akt signaling pathway-related proteins showed the same trend. GDM and Se deficiency affected the growth and glucose metabolism of offspring through oxidative stress and PI3K/Akt signaling pathway-related proteins, and gender differences existed.


Assuntos
Diabetes Gestacional , Desnutrição , Selênio , Gravidez , Humanos , Masculino , Feminino , Animais , Camundongos , Glicemia/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases , Camundongos Endogâmicos C57BL , Lactação
7.
Analyst ; 148(22): 5667-5672, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37812430

RESUMO

The study of cellular responses linked to oxidative stress mechanisms is crucial in comprehending diverse physiological and pathological life processes, including mitochondrial dysfunction. Nonetheless, despite the interference of O2, the monitoring of ROS released from cells poses a challenging task. In this study, carbon-based copper single-atom catalysts (Cu SACs) were synthesized that exhibits excellent electrocatalytic performance for H2O2 reduction with an initial potential at 0.23 V and effectively avoids interference from O2. Based on this catalyst, a flexible and stretchable oxygen-tolerant sensor was constructed and applied to monitor the calcium ion-induced ROS burst in human umbilical vein endothelial cells (HUVECs) in a simulated physiological condition. This study effectively eradicates interference that may arise from the reduction of O2 and presents a dependable platform for real-time in situ monitoring of physiologically active molecules by utilizing H2O2 detection.


Assuntos
Peróxido de Hidrogênio , Oxigênio , Humanos , Peróxido de Hidrogênio/farmacologia , Espécies Reativas de Oxigênio , Cobre/química , Células Endoteliais da Veia Umbilical Humana
8.
Food Chem X ; 18: 100712, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37397206

RESUMO

A preliminary study was conducted of the chemical, structural properties and immunomodulatory activities of fucoidan isolated from Sargassum Zhangii (SZ). Sargassum Zhangii fucoidan (SZF) was determined to have a sulfate content of 19.74 ± 0.01% (w/w) and an average molecular weight of 111.28 kDa. SZF possessed a backbone structure of (1,4)-α-d-linked-galactose, (3,4)-α-l-fucose, (1,3)-α-d-linked-xylose, ß-d-linked-mannose and a terminal (1,4)-α-d-linked-glucose. The main monosaccharide composition was determined as (w/w) 36.10% galactose, 20.13% fucose, 8.86% xylose, 7.36% glucose, 5.62% mannose, and 18.07% uronic acids, respectively. An immunostimulatory assay showed that SZF, compared to commercial fucoidans (Undaria pitnnaifida and Fucus vesiculosus sources), significantly elevated nitric oxide production via up-regulation of cyclooxygenase-2 and inducible nitric oxide synthase at both gene and protein levels. These results suggest that SZ has the potential to be a source of fucoidan with enhanced properties that may act as a useful ingredient for functional foods, nutritional supplements, and immune enhancers.

9.
Front Pharmacol ; 14: 1208740, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492092

RESUMO

Cancer is one of the important factors threatening human health. Hence, it is essential to create novel potent drugs to treat it. Due to the strong correlation among histone deacetylase1 (HDAC1), speckle-type POZ protein (SPOP) and cancers, dual inhibition of HDAC1 and SPOP may be a promising strategy for cancer treatment. In this study, we successfully identified four potential dual-targeting HDAC1/SPOP candidate compounds with structure-based virtual screening. In vitro inhibition experiments confirmed that the four compounds had dual inhibitory effects on HDAC1 and SPOP. Among them, compound HS-2 had a stronger inhibitory effect on HDAC1 and SPOP than the positive controls. Further molecular dynamics simulations indicated that HS-2 could stably bind to HDAC1 and SPOP. In addition, MTT assay indicated that HS-2 inhibited the growth of tumor cells in the micromolar range. In vivo evaluation showed that HS-2 could obviously inhibit the growth of tumor in nude mice without obvious toxicity. These findings suggest that HS-2 is a novel and potent dual-targeting HDAC1/SPOP inhibitor for cancer treatment.

10.
Talanta ; 265: 124860, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37429254

RESUMO

Superoxide anion (O2•-) is typically produced in living cells and organisms, while excess O2•- may cause unexpected damage, so monitoring and scavenging the O2•- is of considerable significance to exploring physiological and pathological process. In this study, a Cu-based metal-organic framework (Cu-MOF) which comprise sequential Cu metal ion and conductive organic 2,5-dicarboxylic acid-3,4-ethylene dioxythiophene is synthesized to mimic superoxide dismutase (SOD), in which Cu is the essence of active site. On one hand, the Cu-MOF possesses excellent electrocatalytic activity to detect O2•- at -0.05 V, biased at which potential the electrode showed good linearity toward O2•- with detection limit of 0.283 µM and interference immunity for AA, DA, UA, 5-HT and H2O2. The Cu-MOF modified microelectrode was applied for measuring the O2•- released from living cells real time and monitoring O2•- generation in rat brain. On the other hand, this Cu-MOF has the catalytic activity to mimic the superoxide dismutase for scavenging O2•- in HeLa cells effectively. This work provides a methodology to design metal ion based enzyme mimetic for analyzing and scavenging O2•- in cells and in vivo.


Assuntos
Estruturas Metalorgânicas , Superóxidos , Humanos , Animais , Ratos , Superóxidos/química , Superóxido Dismutase , Células HeLa , Peróxido de Hidrogênio/química , Microeletrodos
11.
Pharmaceuticals (Basel) ; 16(6)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37375807

RESUMO

The COVID-19 pandemic has had a profound impact worldwide, resulting in long-term health effects for many individuals. Recently, as more and more people recover from COVID-19, there is an increasing need to identify effective management strategies for post-COVID-19 syndrome, which may include diarrhea, fatigue, and chronic inflammation. Oligosaccharides derived from natural resources have been shown to have prebiotic effects, and emerging evidence suggests that they may also have immunomodulatory and anti-inflammatory effects, which could be particularly relevant in mitigating the long-term effects of COVID-19. In this review, we explore the potential of oligosaccharides as regulators of gut microbiota and intestinal health in post-COVID-19 management. We discuss the complex interactions between the gut microbiota, their functional metabolites, such as short-chain fatty acids, and the immune system, highlighting the potential of oligosaccharides to improve gut health and manage post-COVID-19 syndrome. Furthermore, we review evidence of gut microbiota with angiotensin-converting enzyme 2 expression for alleviating post-COVID-19 syndrome. Therefore, oligosaccharides offer a safe, natural, and effective approach to potentially improving gut microbiota, intestinal health, and overall health outcomes in post-COVID-19 management.

12.
Front Microbiol ; 14: 1169884, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37303782

RESUMO

Edible fungi are not only delicious but are also rich in nutritional and medicinal value, which is highly sought after by consumers. As the edible fungi industry continues to rapidly advance worldwide, particularly in China, the cultivation of superior and innovative edible fungi strains has become increasingly pivotal. Nevertheless, conventional breeding techniques for edible fungi can be arduous and time-consuming. CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9) is a powerful tool for molecular breeding due to its ability to mediate high-efficiency and high-precision genome modification, which has been successfully applied to many kinds of edible fungi. In this review, we briefly summarized the working mechanism of the CRISPR/Cas9 system and highlighted the application progress of CRISPR/Cas9-mediated genome-editing technology in edible fungi, including Agaricus bisporus, Ganoderma lucidum, Flammulina filiformis, Ustilago maydis, Pleurotus eryngii, Pleurotus ostreatus, Coprinopsis cinerea, Schizophyllum commune, Cordyceps militaris, and Shiraia bambusicola. Additionally, we discussed the limitations and challenges encountered using CRISPR/Cas9 technology in edible fungi and provided potential solutions. Finally, the applications of CRISPR/Cas9 system for molecular breeding of edible fungi in the future are explored.

13.
Int J Biol Macromol ; 243: 125300, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37315669

RESUMO

Monoacylglycerol lipase (MAGL) involved in regulating plant growth and development and stress responses, hydrolyzes monoacylglycerol (MAG) into free fatty acid and glycerol, which is the last step of triacylglycerol (TAG) breakdown. Here, a genome-wide characterization of MAGL gene family from cultivated peanut (Arachis hypogaea L.) was performed. In total, 24 MAGL genes were identified and unevenly distributed on 14 chromosomes, encoding 229-414 amino acids with molecular weights ranging from 25.91 to 47.01 kDa. Spatiotemporal and stress-induced expression was analyzed by qRT-PCR. Multiple sequence alignment revealed that AhMAGL1a/b and AhMAGL3a/b were the only four bifunctional enzymes with conserved regions of hydrolase and acyltransferase, which could also be named as AhMGATs. GUS histochemical assay showed that AhMAGL1a and -1b were strongly expressed in all tissues of the plants; whereas both AhMAGL3a and -3b were weakly expressed in plants. Subcellular localization analysis indicated that AhMGATs were localized in the endoplasmic reticulum and/or Golgi complex. Seed-specific overexpression of AhMGATs in Arabidopsis decreased the oil content of the seeds and altered the fatty acid compositions, indicating that AhMGATs were involved in TAG breakdown but not TAG biosynthesis in plant seeds. This study lays the foundation for better understanding AhMAGL genes biological function in planta.


Assuntos
Arabidopsis , Arachis , Monoacilglicerol Lipases/genética , Monoacilglicerol Lipases/metabolismo , Metabolismo dos Lipídeos/genética , Ácidos Graxos/metabolismo , Arabidopsis/genética , Sementes , Regulação da Expressão Gênica de Plantas
14.
Foods ; 12(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36900632

RESUMO

Morchella esculenta is an edible mushroom with special flavor and high nutritional value for humans, primarily owing to its polysaccharide constituents. M. esculenta polysaccharides (MEPs) possess remarkable pharmaceutical properties, including antioxidant, anti-inflammatory, immunomodulatory, and anti-atherogenic activities. The aim of this study was to evaluate the in vitro and in vivo antioxidant potential of MEPs. In vitro activity was determined using free radical scavenging assays, whereas in vivo activity was evaluated through dextran sodium sulfate (DSS)-induced liver injury in mice with acute colitis. MEPs effectively scavenged 1,1-diphenyl-2-picrylhydrazyl and 2,2-azinobis-6-(3-ethylbenzothiazoline sulfonic acid) free radicals in a dose-dependent manner. Additionally, DSS-induced mice showed severe liver damage, cellular infiltration, tissue necrosis, and decreased antioxidant capacity. In contrast, intragastric administration of MEPs showed hepatoprotective effects against DSS-induced liver injury. MEPs remarkably elevated the expression levels of superoxide dismutase, glutathione peroxidase, and catalase. Additionally, it decreased malondialdehyde and myeloperoxidase levels in the liver. These results indicate that the protective effects of MEP against DSS-induced hepatic injury could rely on its ability to reduce oxidative stress, suppress inflammatory responses, and improve antioxidant enzyme activity in the liver. Therefore, MEPs could be explored as potential natural antioxidant agents in medicine or as functional foods to prevent liver injury.

15.
Sci Rep ; 13(1): 4851, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964182

RESUMO

Nicotiana alata Link et Otto, widely used in landscaping, is not only of great ornamental value but also of high commercial and medical value. The global potential habitat of N. alata and the environmental factors affecting its distribution are not that clear at present. To provide a reference for the reasonable and extensive planting of N. alata now and in the future, the MaxEnt model was used to predict its global suitable habitats under current and future climate conditions, respectively, based on global geographic distribution data of N. alata and the current and future world bioclimatic variables. The results showed that mean temperature of the driest quarter (bio9), precipitation of driest month (bio14), precipitation seasonality (bio15) and max temperature of warmest month (bio5), were the key bioclimatic variables governing the distribution of N. alata. The global suitable habitats of N. alata were mainly distributed in Europe, the United States, southeastern South America, and China under current climate conditions. Compared with current climate conditions, the future climate decreased suitable habitats of N. alata under SSP1-2.6, and SSP2-4.5 scenario and increased suitable habitats of N. alata under SSP3-7.0, and SSP5-8.5 climatic scenarios. The results provided valuable information and theoretical reference for the reasonable planting of N. alata.


Assuntos
Mudança Climática , Ecossistema , Temperatura , China
16.
Environ Res ; 224: 115447, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36758919

RESUMO

A green, high-efficiency, and wide pH tolerance water remediation process has been urgently acquired for the increasingly exacerbating contaminated water. In this study, a Fe3+/persulfate (Fe3+/PS) system was employed and enhanced with a green natural ligand cysteine (Cys) for the degradation of quinclorac (QNC). The introduction of Cys into the Fe3+/PS system widened the effective pH range to 9 with a superior removal rate for QNC. The mechanism revealed that the Fe3+/Cys/PS system can enhance the ability of degrading QNC by accelerating the Fe3+/Fe2+ redox cycle, maintaining Fe2+ concentration and thereby generating more HO• and SO4•-. The impact factors (i.e., pH, concentrations of PS, Fe3+ and Cys) were optimized as well. This work provides a promising strategy with high catalytic activity and wide pH tolerance for organic contaminated water remediation.


Assuntos
Quinolinas , Poluentes Químicos da Água , Purificação da Água , Cisteína/química , Concentração de Íons de Hidrogênio , Oxirredução , Água , Poluentes Químicos da Água/análise , Química Verde
17.
Micromachines (Basel) ; 13(10)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36296001

RESUMO

The main purpose of this study is to explore a surface roughness prediction model of Gas-Solid Two-Phase Abrasive Flow Machining. In order to achieve the above purpose, an orthogonal experiment was carried out. Q235 steel as processing material and white corundum with different particle sizes as abrasive particles were used in the experiment. Shape and spindle speed were the main reference factors. The range method and factor trend graph are used to comprehensively analyze the experimental results of different processing stages of the detection point, and the optimal parameter combination of A3B2C1D2 was obtained. According to the experimental results, a multiple linear regression equation was established to predict the surface roughness, and the experimental results were solved and significantly analyzed by software to obtain a highly reliable prediction model. Through experiments, modeling and verification, it is known that the maximum error between the obtained model and the actual value is 0.339 µm and the average error is 0.00844 µm, which can better predict the surface roughness of the gas-solid two-phase flow abrasive pool.

18.
Analyst ; 147(18): 4055-4062, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35968779

RESUMO

Cell mechanotransduction plays an important role in vascular regulation and disease development. Excessive accumulation of ROS, especially superoxide anion radicals (O2˙-), is closely related to cardiovascular diseases. Lately, NADPH oxidases, which are the major source of O2˙- production in vascular tissues, have been demonstrated to be involved in cardiovascular diseases. Therefore, in situ and real-time monitoring of superoxide anions (O2˙-) is essential for exploring the mechanisms of mechanotransduction associated with NADPH oxidase function in living cells. Here we report a rationally designed ultrasonication-assisted approach for growing Au nanoflower films on a flexible surface, which serves as the desired interface for cysteine and superoxide dismutase (SOD) anchoring to form a flexible and stretchable electrode (SOD/Cys/Au SE). The SOD/Cys/Au SE shows good stretchability, fast electron-transfer rates, and high selectivity to measure O2˙- released from cells during the stretching states. Our strategy provides a basis for developing more sophisticated stretchable biosensing tools to induce and monitor transient biochemical signals during cell mechanotransduction.


Assuntos
Técnicas Biossensoriais , Doenças Cardiovasculares , Humanos , Mecanotransdução Celular , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo
19.
Biomed Chromatogr ; 36(8): e5395, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35514216

RESUMO

A rapid, selective and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to detect meloxicam in human plasma. A triple quadrupole tandem mass spectrometer equipped with an electrospray ionization source was used in positive ion mode. Protein precipitation with acetonitrile was used for sample preparation. Meloxicam and 13 C6 -meloxicam internal standard were analyzed on an Acquity CSH C18 column with a mobile phase of acetonitrile and water in 0.1% formic acid using a gradient program for separation. The retention time of meloxicam was 1.1 min and the total run time was only 2.0 min. Detection was performed in multiple reaction monitoring mode using an electrospray ionization source with optimized mass spectrometry parameters. The calibration curves were linear in the range 10.0-3.00 × 103 ng/ml (r ≥ 0.99). The within-run and between-run RSDs were ≤14.8%. The within-run and between-run REs ranged from -4.6 to 10.7%. There was no significant matrix effect, and the recovery rate was high. This method was fully validated, including reinjection reproducibility in human plasma. The method was applied to the pharmacokinetic study. All of the incurred sample reanalysis methods met the criteria.


Assuntos
Espectrometria de Massas em Tandem , Acetonitrilas , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Meloxicam , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
20.
Entropy (Basel) ; 24(4)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35455200

RESUMO

Full-duplex (FD) transmission holds a great potential of improving the sum data rate of wireless communication systems. However, the self-interference introduced by the full-duplex transmitter brings a big challenge to enhance the energy efficiency. This paper investigates the power allocation problem in a full-duplex two-way (FDTW) communication network over an OFDM channel, aiming at improving the sum data rate and energy efficiency. We first characterize the sum rate and energy efficiency achieved in a single-carrier FDTW system. The optimal transmit power that achieves the maximal sum data rate is presented. The energy efficiency maximization problem is solved by using fractional programming. Then we further formulate sum rate and energy efficiency maximization problem in a multi-subcarrier FDTW system. In particular, the sub-optimal transmit power allocation which achieves a decent sum rate improvement is found by using a proposed iterative algorithm. By combining the iterative algorithm and fractional programming, we further maximize the energy efficiency of the multi-subcarrier system. With our proposed algorithm, we can easily obtain an optimal transmit power that approximates the global optimal solution. Simulation results show that using the obtained optimal transmit power allocation algorithm can significantly improve the sum rate and energy efficiency in both single-carrier and multi-subcarrier systems.

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