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1.
Nano Lett ; 24(17): 5197-5205, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38634879

RESUMO

Highly active nonprecious-metal single-atom catalysts (SACs) toward catalytic transfer hydrogenation (CTH) of α,ß-unsaturated aldehydes are of great significance but still are deficient. Herein, we report that Zn-N-C SACs containing Zn-N3 moieties can catalyze the conversion of cinnamaldehyde to cinnamyl alcohol with a conversion of 95.5% and selectivity of 95.4% under a mild temperature and atmospheric pressure, which is the first case of Zn-species-based heterogeneous catalysts for the CTH reaction. Isotopic labeling, in situ FT-IR spectroscopy, and DFT calculations indicate that reactants, coabsorbed at the Zn sites, proceed CTH via a "Meerwein-Ponndorf-Verley" mechanism. DFT calculations also reveal that the high activity over Zn-N3 moieties stems from the suitable adsorption energy and favorable reaction energy of the rate-determining step at the Zn active sites. Our findings demonstrate that Zn-N-C SACs hold extraordinary activity toward CTH reactions and thus provide a promising approach to explore the advanced SACs for high-value-added chemicals.

2.
Nano Lett ; 23(11): 5123-5130, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37272668

RESUMO

Developing cost-effective and highly efficient photocathodes toward polysulfide redox reduction is highly desirable for advanced quantum dot (QD) photovoltaics. Herein, we demonstrate nitrogen doped carbon (N-C) shell-supported iron single atom catalysts (Fe-SACs) capable of catalyzing polysulfide reduction in QD photovoltaics for the first time. Specifically, Fe-SACs with FeN4 active sites feature a power conversion efficiency of 13.7% for ZnCuInSe-QD photovoltaics (AM1.5G, 100 mW/cm2), which is the highest value for ZnCuInSe QD-based photovoltaics, outperforming those of Cu-SACs and N-C catalysts. Compared with N-C, Fe-SACs exhibit suitable energy level matching with polysulfide redox couples, revealed by the Kelvin probe force microscope, which accelerates the charge transferring at the interfaces of catalyst/polysulfide redox couple. Density functional theory calculations demonstrate that the outstanding catalytic activity of Fe-SACs originates from the preferable adsorption of S42- on the FeN4 active sites and the high activation degree of the S-S bonds in S42- initiated by the FeN4 active sites.

3.
Sensors (Basel) ; 23(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37112443

RESUMO

In the field of AGV, a path planning algorithm is always a heated area. However, traditional path planning algorithms have many disadvantages. To solve these problems, this paper proposes a fusion algorithm that combines the kinematical constraint A* algorithm and the following dynamic window approach algorithm. The kinematical constraint A* algorithm can plan the global path. Firstly, the node optimization can reduce the number of child nodes. Secondly, improving the heuristic function can increase efficiency of path planning. Thirdly, the secondary redundancy can reduce the number of redundant nodes. Finally, the B spline curve can make the global path conform to the dynamic characteristics of AGV. The following DWA algorithm can be dynamic path planning and allow the AGV to avoidance moving obstacle. The optimization heuristic function of the local path is closer to the global optimal path. The simulation results show that, compared with the fusion algorithm of traditional A* algorithm and traditional DWA algorithm, the fusion algorithm reduces the length of path by 3.6%, time of path by 6.7% and the number of turns of final path by 25%.

4.
Arch Biochem Biophys ; 697: 108694, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33232716

RESUMO

Excessive ethanol consumption causes cellular damage, leading to fetal alcohol syndrome and alcohol liver diseases, which are frequently seen with vitamin D (VD) deficiency. A great deal of progress has been achieved in the mechanisms of ethanol-induced hepatocyte damage. However, there are limited intervention means to reduce or rescue hepatocytes damage caused by ethanol. On the basis of our preliminary limited screen process, calcitriol showed a positive effect on protecting hepatocyte viability. Therefore, the molecular basis is worth elucidating. We found that calcitriol pretreatment markedly improved the cell viability, decreased cell apoptosis and oxidative stress and alleviated the abnormal mitochondrial morphology and membrane potential of hepatocytes induced by ethanol. Notably, autophagy was significantly enhanced by calcitriol, as evident by the increasing number of autophagosomes and autolysosomes, upregulated LC3B-Ⅱ and ATG5 levels, and promotion of p62 degradation. Furthermore, calcitriol pretreatment increased the colocalization of GFP-LC3-labeled autophagosomes with mitochondria, suggesting that calcitriol effectively promoted ethanol-induced mitophagy in hepatocytes. In addition, the inhibition of autophagy attenuated the protective and preventive effect of calcitriol. Furthermore, the effect of calcitriol on autophagy was regulated by AMPK/mTOR signaling, and signaling transduction was dependent on the Vitamin D receptor (VDR). In conclusion, calcitriol ameliorates ethanol-induced hepatocyte damage by enhancing autophagy. It may offer a convenient preventive and hepatoprotective mean for people on occasional social drink.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/efeitos dos fármacos , Calcitriol/farmacologia , Etanol/toxicidade , Fígado/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Fígado/citologia , Fígado/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitofagia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Receptores de Calcitriol/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
Biochem Biophys Res Commun ; 529(2): 474-479, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32703454

RESUMO

Currently, there is a growing interest in understanding the cellular and molecular events of immune-cell trafficking and recruitment of hepatic stellate cells (HSCs) in liver diseases. Aberrant activation of HSCs is the key event leading to chronic liver fibrosis. However, the underlying mechanisms of the recruitment of HSCs in a locally injured liver are not clearly understood. Here, we report a new experimental approach for the study of inflammatory responses as well as the recruitment of HSCs into the localized cryolesion. We observed a significant liver damage accompanied by the up-regulation of plasma ALT and AST. In addition, we also found increased levels of MCP-1, IL-6 and IL-10 cytokines. The peak cytokine levels were detected at 8 h after injury, followed by intrahepatic infiltration of neutrophils and monocytes into the injury site (from 8 h to day 3), while the kupffer cells (KCs) and HSCs were mainly detected on day 3 after injury. Interestingly, the depletion of KCs, but not neutrophils, reduced the directional recruitment and accumulation of HSCs at the injury site. Moreover, the combinatorial recruitment of KCs and HSCs resulted in the gradual restoration of fibrotic area to almost typical histological appearance on day 14 post-injury. In conclusion, our data demonstrated a localized infiltration and accumulation of neutrophils and monocytes at a "predefined loci", and further revealed that KCs are critical for the recruitment of HSCs during injury, and thus, may play an important role in tissue repair.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/patologia , Células Estreladas do Fígado/patologia , Células de Kupffer/patologia , Cirrose Hepática/patologia , Animais , Tetracloreto de Carbono , Movimento Celular , Modelos Animais de Doenças , Feminino , Fígado/patologia , Camundongos Endogâmicos C57BL
6.
Biosci Biotechnol Biochem ; 84(8): 1645-1651, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32380907

RESUMO

Oxaliplatin (L-OHP) is one of the effective chemotherapeutic drugs for colorectal cancer (CRC). Further investigation into the molecular mechanism of chemoresistance could improve outcomes for patients with colorectal cancer. Recently, microRNAs have been reported as a key in drug resistance of tumors. In this study, we aimed to investigate the effects of miR-153-5p in L-OHP-resistant CRC cells, and its underlying mechanism. Downregulation of miR-153-5p was observed in CRC cells, while upregulation of miR-153-5p enhances the chemosensitivity of CRC/L-OHP cells. The autophagy of CRC/L-OHP cells was markedly increased after exposure to L-OHP but abolished by the upregulation of miR-153-5p. Dual-luciferase reporter assays validated that Bcl-2 was a direct target of miR-153-5p. In conclusion, our data suggested that miR-153-5p was a mediator of cisplatin resistance in colorectal cancer by affecting Bcl-2-mediated autophagy, indicating a new therapeutic target for CRC treatment.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , Oxaliplatina/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Antagomirs/genética , Antagomirs/metabolismo , Autofagia/genética , Pareamento de Bases , Sequência de Bases , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , MicroRNAs/agonistas , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Oligorribonucleotídeos/genética , Oligorribonucleotídeos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais
7.
Clin Lab ; 62(6): 1101-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27468572

RESUMO

BACKGROUND: Recently, autoimmune mechanisms and pulmonary epithelial cells have attracted attention in chronic obstructive pulmonary disease (COPD). Circulating antibodies against human bronchial epithelial cells (anti-HBEC) bind to bronchial epithelial antigens and induce bronchial epithelial cell damage. This study aimed to detect the expression of IgG, IgM, and IgA anti-HBEC in patients with COPD. METHODS: The association of gender, age, body mass index (BMI), and pulmonary function with the presence of IgG, IgA, and IgM anti-HBEC in the plasma was determined in 170 patients with COPD and 150 age-matched healthy controls. Circulating IgG, IgA, and IgM anti-HBEC were detected by indirect immunofluorescence (IIF). RESULTS: Positive IgG anti-HBEC was seen in 34/170 (20.00%) COPD and 11/150 (7.33%) healthy controls (p < 0.001) (1:100 dilution); positive IgA anti-HBEC were presented in 50/170 (29.41%) COPD and 13/150 (8.67%) healthy controls (p < 0.0001) (1:40 dilution); 19/170 (11.19%) COPD and 10/150 (6.67%) healthy controls exhibited positive IgM anti-HBEC (p > 0.05) (1:40 dilution). The positive IgG and IgA anti-HBEC COPD patients were mostly classified as GOLD (Global Initiative for Chronic Obstructive Lung Disease) III and GOLD IV. The positive IgA anti-HBEC COPD patients had lower BMI than healthy controls (p < 0.05). CONCLUSIONS: Our results suggest that an autoimmune component associated with bronchial epithelial cell damage is possibly involved in COPD and the presence of IgG and IgA anti-HBEC correlated with the GOLD stage of COPD. Therefore, our studies indicate that IgG and IgA anti-HBEC may associate with the disease severity of COPD.


Assuntos
Autoanticorpos/imunologia , Brônquios/imunologia , Células Epiteliais/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/sangue , Autoimunidade , Estudos de Casos e Controles , Células Cultivadas , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Índice de Gravidade de Doença
8.
Sci Rep ; 14(1): 8942, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637556

RESUMO

This paper presents a fusion algorithm based on the enhanced RRT* TEB algorithm. The enhanced RRT* algorithm is utilized for generating an optimal global path. Firstly, proposing an adaptive sampling function and extending node bias to accelerate global path generation and mitigate local optimality. Secondly, eliminating path redundancy to minimize path length. Thirdly, imposing constraints on the turning angle of the path to enhance path smoothness. Conducting kinematic modeling of the mobile robot and optimizing the TEB algorithm to align the trajectory with the mobile robot's kinematics. The integration of these two algorithms culminates in the development of a fusion algorithm. Simulation and experimental results demonstrate that, in contrast to the traditional RRT* algorithm, the enhanced RRT* algorithm achieves a 5.8% reduction in path length and a 62.5% decrease in the number of turning points. Utilizing the fusion algorithm for path planning, the mobile robot generates a superior, seamlessly smooth global path, adept at circumventing obstacles. Furthermore, the local trajectory meticulously conforms to the kinematic constraints of the mobile robot.

9.
Diabetes Metab J ; 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38310881

RESUMO

Background: Insulin resistance (IR) is the key pathological basis of many metabolic disorders. Lack of asialoglycoprotein receptor 1 (ASGR1) decreased the serum lipid levels and reduced the risk of coronary artery disease. However, whether ASGR1 also participates in the regulatory network of insulin sensitivity and glucose metabolism remains unknown. Methods: The constructed ASGR1 knockout mice and ASGR1-/- HepG2 cell lines were used to establish the animal model of metabolic syndrome and the IR cell model by high-fat diet (HFD) or drug induction, respectively. Then we evaluated the glucose metabolism and insulin signaling in vivo and in vitro. Results: ASGR1 deficiency ameliorated systemic IR in mice fed with HFD, evidenced by improved insulin intolerance, serum insulin, and homeostasis model assessment of IR index, mainly contributed from increased insulin signaling in the liver, but not in muscle or adipose tissues. Meanwhile, the insulin signal transduction was significantly enhanced in ASGR1-/- HepG2 cells. By transcriptome analyses and comparison, those differentially expressed genes between ASGR1 null and wild type were enriched in the insulin signal pathway, particularly in phosphoinositide 3-kinase-AKT signaling. Notably, ASGR1 deficiency significantly reduced hepatic gluconeogenesis and glycogenolysis. Conclusion: The ASGR1 deficiency was consequentially linked with improved hepatic insulin sensitivity under metabolic stress, hepatic IR was the core factor of systemic IR, and overcoming hepatic IR significantly relieved the systemic IR. It suggests that ASGR1 is a potential intervention target for improving systemic IR in metabolic disorders.

10.
Food Chem X ; 20: 100887, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144739

RESUMO

The simultaneous determination of multi-mycotoxins in food commodities are highly desirable due to their potential toxic effects and mass consumption of foods. Herein, liquid chromatography-quadrupole exactive orbitrap mass spectrometry was proposed to analyze multi-mycotoxins in commercial vegetable oils. Specifically, the method featured a successive liquid-liquid extraction process, in which the complementary solvents consisted of acetonitrile and water were optimized. Resultantly, matrix effects were reduced greatly. External calibration approach revealed good quantification property for each analyte. Under optimal conditions, the recovery ranging from 80.8% to 109.7%, relative standard deviation less than 11.7%, and good limit of quantification (0.35 to 45.4 ng/g) were achieved. The high accuracy of proposed method was also validated. The detection of 20 commercial vegetable oils revealed that aflatoxins B1 and B2, zearalenone were observed in 10 real samples. The as-developed method is simple and low-cost, which merits the wide applications for scanning mycotoxins in oil matrices.

11.
Zootaxa ; 5315(3): 251-263, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37518604

RESUMO

The name Striatochrista nom. n. is introduced as replacement for Striatella Volynkin & S.-Y. Huang, 2019. A new genus, Letrasilta S.-Y. Huang & Volynkin gen. n. is erected to include the Striatella cernyi species-group with the new species, L. ratnasambhava S.-Y. Huang, Volynkin & Yin sp. n. from Xizang, southwestern China designated as the type species. Based on the molecular phylogenetic analysis, the new genus is found to be sister to the clade (Aberrasine + ((Indiania + Idopterum) + Striatochrista nom. n.)) but is distinguished from all the relevant genera by the unique genitalia features. Letrasilta cernyi (Volynkin, 2018) comb. n. is also reported from India for the first time. Adults and genitalia of the aforementioned taxa are illustrated. A checklist of the genus Striatochrista is also provided.


Assuntos
Mariposas , Filogenia , Animais , China , Genitália/anatomia & histologia , Mariposas/anatomia & histologia , Mariposas/classificação , Mariposas/genética , Genes de Insetos/genética , Especificidade da Espécie
12.
ACS Appl Mater Interfaces ; 15(40): 46925-46932, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37769342

RESUMO

Titania nanospheres have been utilized as building blocks of electron transporting layers (ETLs) for mesoscopic perovskite solar cells (PSCs). Nevertheless, the power conversion efficiencies (PCEs) reported so far for the mesoscopic PSCs containing titania nanospheres are generally lower than those of the state-of-the-art planar PSCs. Here, we have prepared Li-doped hollow titania nanospheres (Li-HTS) through a "cation-exchange" approach and used them for the first time to modify the SnO2 ETL/perovskite interfaces of planar PSCs. The Li-HTS-modified PSC delivered a PCE of 23.28% with a fill factor (FF) of over 80%, which is significantly higher than the PCE of the control device (20.51%). This is the best PCE achieved for PSCs containing titania nanospheres. Moreover, interfacial modification using Li-HTS greatly improves the stability of the PSCs. This work demonstrates the potential of interface modification using inorganic nanostructures for enhancing the efficiency and stability of planar PSCs.

13.
Front Plant Sci ; 14: 1283315, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38155856

RESUMO

The ongoing global warming trajectory poses extensive challenges to plant ecosystems, with rubber plantations particularly vulnerable due to their influence on not only the longevity of the growth cycle and rubber yield, but also the complex interplay of carbon, water, and energy exchanges between the forest canopy and atmosphere. However, the response mechanism of phenology in rubber plantations to climate change remains unclear. This study concentrates on sub-optimal environment rubber plantations in Yunnan province, Southwest China. Utilizing the Google Earth Engine (GEE) cloud platform, multi-source remote sensing images were synthesized at 8-day intervals with a spatial resolution of 30-meters. The Normalized Difference Vegetation Index (NDVI) time series was reconstructed using the Savitzky-Golay (S-G) filter, coupled with the application of the seasonal amplitude method to extract three crucial phenological indicators, namely the start of the growing season (SOS), the end of the growing season (EOS), and the length of the growing season (LOS). Linear regression method, Pearson correlation coefficient, multiple stepwise regression analysis were used to extract of the phenology trend and find the relationship between SOS, EOS and climate factors. The findings demonstrated that 1) the phenology of rubber plantations has undergone dynamic changes over the past two decades. Specifically, the SOS advanced by 9.4 days per decade (R2 = 0.42, p< 0.01), whereas the EOS was delayed by 3.8 days per decade (R2 = 0.35, p< 0.01). Additionally, the LOS was extended by 13.2 days per decade (R2 = 0.55, p< 0.01); 2) rubber phenology demonstrated a notable sensitivity to temperature fluctuations during the dry season and precipitation patterns during the rainy season. The SOS advanced 2.0 days (r =-0.19, p< 0.01) and the EOS advanced 2.8 days (r =-0.35, p< 0.01) for every 1°C increase in the cool-dry season. Whereas a 100 mm increase in rainy season precipitation caused the SOS to be delayed by 2.0 days (r = 0.24, p< 0.01), a 100 mm increase in hot-dry season precipitation caused the EOS to be advanced by 7.0 days (r =-0.28, p< 0.01); 3) rubber phenology displayed a legacy effect of preseason climate variations. Changes in temperature during the fourth preseason month and precipitation during the fourth and eleventh preseason months are predominantly responsible for the variation in SOS. Meanwhile, temperature changes during the second, fourth, and ninth preseason months are primarily responsible for the variation in EOS. The study aims to enhance our understanding of how rubber plantations respond to climate change in sub-optimal environments and provide valuable insights for sustainable rubber production management in the face of changing environmental conditions.

14.
Life Sci Alliance ; 6(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410795

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is prevalent worldwide; about 25% of NAFLD silently progress into steatohepatitis, in which some of them may develop into fibrosis, cirrhosis and liver failure. However, few drugs are available for NAFLD, partly because of an incomplete understanding of its pathogenic mechanisms. Here, using in vivo and in vitro gain- and loss-of-function approaches, we identified up-regulated DKK1 plays a pivotal role in high-fat diet-induced NAFLD and its progression. Mechanistic analysis reveals that DKK1 enhances the capacity of hepatocytes to uptake fatty acids through the ERK-PPARγ-CD36 axis. Moreover, DKK1 increased insulin resistance by activating the JNK signaling, which in turn exacerbates disorders of hepatic lipid metabolism. Our finding suggests that DKK1 may be a potential therapeutic and diagnosis candidate for NAFLD and metabolic disorder progression.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Dieta Hiperlipídica , Hepatócitos , Peptídeos e Proteínas de Sinalização Intercelular , Metabolismo dos Lipídeos/genética , Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica/genética , Antígenos CD36/metabolismo
15.
J Ultrasound Med ; 31(9): 1333-40, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22922612

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the effectiveness of sonographically guided hand kneading and compression for the treatment of femoral artery pseudoaneurysms after percutaneous intervention. METHODS: Twenty-four patients who had post-percutaneous intervention femoral artery pseudoaneurysms treated with sonographically guided compression from 2001 to 2004 and 2008 to 2009 were compared with 25 patients who had postintervention pseudoaneurysms treated with sonographically guided hand kneading and compression from 2005 to 2009. RESULTS: All 25 patients (100%) treated with 1-stage sonographically guided hand kneading and compression had pseudoaneurysm occlusion; the median treatment time was 10 minutes. Twenty-two of the 24 patients (91.7%) treated with conventional sonographically guided compression had pseudoaneurysm occlusion. One-stage compression was successful in 10 patients; 9 and 3 patients had pseudoaneurysm occlusion after 2 and 3 compression treatments, respectively. Two other patients who underwent compression treatment 3 and 4 times did not have pseudoaneurysm occlusion and required surgery. The median treatment time for sonographically guided compression was 30 minutes. The treatment time was significantly shorter for the hand-kneading and compression technique (P < .001), and significantly fewer procedures were needed (P < .001). CONCLUSIONS: Sonographically guided hand kneading and compression is as effective as sonographically guided compression alone for pseudoaneurysm occlusion after femoral artery percutaneous intervention and requires significantly less time to perform.


Assuntos
Falso Aneurisma/terapia , Artéria Femoral/diagnóstico por imagem , Massagem , Ultrassonografia de Intervenção/métodos , Idoso , Falso Aneurisma/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Pressão , Estatísticas não Paramétricas , Resultado do Tratamento
16.
Microsc Microanal ; 18(1): 99-106, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22214557

RESUMO

A novel self-organizing behavior of cellularized gels composed of collagen type 1 that may have utility for tissue engineering is described. Depending on the starting geometry of the tissue culture well, toroidal rings of cells or hollow spheroids were prompted to form autonomously when cells were seeded onto the top of gels and the gels released from attachment to the culture well 12 to 24 h after seeding. Cells within toroids assumed distinct patterns of alignment not seen in control gels in which cells had been mixed in. In control gels, cells formed complex three-dimensional arrangements and assumed relatively higher levels of heterogeneity in expression of the fibronectin splice variant ED-A--a marker of epithelial mesenchymal transformation. The tissue-like constructs resulting from this novel self-organizing behavior may have uses in wound healing and regenerative medicine, as well as building blocks for the iterative assembly of synthetic biological structures.


Assuntos
Colágeno/metabolismo , Hidrogéis , Engenharia Tecidual/métodos , Animais , Humanos , Coelhos , Ratos , Medicina Regenerativa/métodos
17.
Chem Commun (Camb) ; 58(60): 8364-8367, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35792051

RESUMO

We designed a novel ratiometric fluorescent probe P1-Leu with a donor-acceptor-donor fluorophore for the detection of leucine aminopeptidase in lysosomes. P1-Leu exhibits a lower detection limit than the ratiometric donor-π-acceptor probe, due to the low ratiometric background. Besides, P1-Leu has good lysosome-targeting ability and realizes the distinction of LAP levels in different cells.


Assuntos
Corantes Fluorescentes , Leucil Aminopeptidase , Lisossomos , Espectrometria de Fluorescência
18.
ACS Omega ; 7(44): 40548-40557, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36385854

RESUMO

Aflatoxin B1 (AFB1) solution certified reference materials (CRMs) have been widely utilized in the measurements of AFB1 contaminations in foods and agricultural products. It is of great importance to evaluate the stability of AFB1 solution CRMs in different matrices for their practical applications. In this study, the stability of AFB1 solution CRM was investigated and its degradation products under various conditions were elucidated using ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry for the first time. Exposure to high temperatures and UV light irradiation accelerated the degradation of AFB1 solution significantly, and the degradation products were largely dependent on the solvents. Two degradation pathways were proposed based on the degradation products. The addition reaction, oxidation reaction, and modification of the methoxy group are the major processes involved in the degradation of the AFB1 solution. The results of this study indicate that the property value of the acetonitrile solution of AFB1 can be well retained when it is stored at temperatures lower than 60 °C, and the exposure to UV light irradiation is avoided.

19.
ACS Appl Mater Interfaces ; 14(11): 13352-13360, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35289163

RESUMO

The interfaces between the absorber and charge transport layers are shown to be critical for the performance of perovskite solar cells (PSCs). PSCs based on the Spiro-OMeTAD hole transport layers generally suffer from the problems of stability and reproducibility. Inorganic hole transport materials CuCrO2 have good chemical stability and high hole mobility. Herein, we reported the preparation of the delafossite-type CuCrO2 nanocrystals with a template-etching-calcination method and the incorporation of the as-obtained CuCrO2 nanocrystals at the perovskite/Spiro-OMeTAD interfaces of planar PSCs to improve the device efficiency and stability. Compared with the traditional hydrothermal method, the template-etching-calcination method used less calcination time to prepare CuCrO2 nanocrystals. After the CuCrO2 interface modification, the efficiency of PSCs improved from 18.08% to 20.66%. Additionally, the CuCrO2-modified PSCs showed good stability by retaining nearly 90% of the initial PCE after being stored in a drybox for 30 days. The template-etching-calcination strategy will pave a new approach for the synthesis of high-performance inorganic hole-transporting materials.

20.
J Cloud Comput (Heidelb) ; 11(1): 37, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093281

RESUMO

This study investigates the possibility of supporting tourists in a foreign land intelligently by using the Tourism Cloud Management System (TCMS) to enhance and better their tourism experience. Some technologies allow tourists to highlight popular tourist routes and circuits through the visualisation of data and sensor clustering approaches. With this, a tourist can access the shared data on a specific location to know the sites of famous local attractions, how other tourists feel about them, and how to participate in local festivities through a smart tourism model. This study surveyed the potential of smart tourism among tourists and how such technologies have developed over time while proposing a TCMS. Its goals were to make physical/paper tickets redundant via the introduction of a mobile app with eTickets that can be validated using camera and QR code technologies and to enhance the transport network using Bluetooth and GPS for real-time identification of tourists' presence. The results show that a significant number of participants engage in tourist travels, hence the need for smart tourism and tourist management. It was concluded that smart tourism is very appealing to tourists and can improve the appeal of the destination if smart solutions are implemented. This study gives a first-hand review of the preference of tourists and the potential of smart tourism.

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