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1.
Small ; : e2311435, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461533

RESUMO

All weather, high-efficiency, energy-saving anti-icing/de-icing materials are of great importance for solving the problem of ice accumulation on outdoor equipment surfaces. In this study, a composite material with energy storage, active electro-/photo-thermal de-icing and passive super-hydrophobic anti-icing properties is proposed. Fluorinated epoxy resin and MWCNTs/PTFE particles are used to prepare the top multifunctional anti-icing/de-icing layer, which exhibited super-hydrophobicity with water contact angle greater than 155° and conductivity higher than 69 S m-1 . The super-hydrophobic durability of the top layer is verified through tape peeling and sandpaper abrasion tests. The surface can be heated by applying on voltage or light illumination, showing efficient electro-/photo-thermal and all-day anti-icing/de-icing performance. The oleogel material at the bottom layer is capable to absorb energy during heating process and release it during cooling process by phase transition, which greatly delayed the freezing time and saved energy. The icing test of single ice droplet, electro-/photo-thermal de-icing and defrosting tests also proved the high efficiency and energy saving of the anti-icing/de-icing strategy. This study provided a new way to manufacture multi-functional materials for practical anti-icing/de-icing applications.

2.
J Control Release ; 367: 441-469, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38295991

RESUMO

Surfaces with high aspect ratio microarray structures can implement sophisticated assignment in typical fields including microfluidics, sensor, biomedicine, et al. via regulating their deformation or the material properties. Inspired by natural materials and systems, for example sea cockroaches, water spiders, cacti, lotus leaves, rice leaves, and cedar leaves, many researchers have focused on microneedle functional surface studies. When the surface with high aspect ratio microarray structures is stimulated by the external fields, such as optical, electric, thermal, magnetic, the high aspect ratio microarray structures can undergo hydrophilic and hydrophobic switching or shape change, which may be gifted the surfaces with the ability to perform complex task, including directional liquid/air transport, targeted drug delivery, microfluidic chip sensing. In this review, the fabrication principles of various surfaces with high aspect ratio microarray structures are classified and summarized. Mechanisms of liquid manipulation on hydrophilic/hydrophobic surfaces with high aspect ratio microarray structures are clarified based on Wenzel model, Cassie model, Laplace pressure theories and so on. Then the intelligent control strategies have been demonstrated. The applications in microfluidic, drug delivery, patch sensors have been discussed. Finally, current challenges and new insights of future prospects for dynamic manipulation of liquid/air based on biomimetic surface with high aspect ratio microarray structures are also addressed.


Assuntos
Microfluídica , Água , Propriedades de Superfície , Interações Hidrofóbicas e Hidrofílicas , Água/química , Eletricidade
3.
Pediatr Res ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253876

RESUMO

BACKGROUND: Irritable bowel syndrome is common in children and exhibits a high placebo response. This study was to explore the placebo response rate and its influencing factors in children with irritable bowel syndrome. METHODS: A systematic search was performed on Pubmed, Embase, MEDLINE, Cochrane Library, CNKI, Wanfang, and CBM from database inception to March 2022. Randomized controlled trials of irritable bowel syndrome in children were included in the study. The primary outcome was the placebo response rate of improvement. RESULTS: Thirteen studies were included, with 445 patients in the placebo group. The rate of improvement and abdominal pain disappearance were 28.2% (95% CI, 16.6-39.9%) and 5% (95% CI, 0-18.4%). The placebo response based on the abdominal pain score was 0.675 (95% CI, 0.203-1.147). The mode of administration (P < 0.01), dosing schedule (P < 0.01), and clinical outcome assessor (P = 0.04) have a significant impact on the magnitude of placebo effect. CONCLUSIONS: The placebo response rate for pediatric irritable bowel syndrome was 28.2%. In clinical trials, reducing dosing frequency, selecting appropriate dosage forms, and using patient-reported outcomes can help mitigate the placebo effect. IMPACT: This is the first meta-analysis to assess the placebo response rates for improvement and disappearance in children with IBS. The finding suggested that the mode of administration, dosing schedule, and clinical outcome assessor could potentially influence the magnitude of the placebo effect in children with IBS. This study would provide a basis for estimating sample size in clinical trial design with a placebo control.

4.
Nat Commun ; 15(1): 844, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38286999

RESUMO

Infection by Helicobacter pylori, a prevalent global pathogen, currently requires antibiotic-based treatments, which often lead to antimicrobial resistance and gut microbiota dysbiosis. Here, we develop a non-antibiotic approach using sonodynamic therapy mediated by a lecithin bilayer-coated poly(lactic-co-glycolic) nanoparticle preloaded with verteporfin, Ver-PLGA@Lecithin, in conjunction with localized ultrasound exposure of a dosage permissible for ultrasound medical devices. This study reveals dual functionality of Ver-PLGA@Lecithin. It effectively neutralizes vacuolating cytotoxin A, a key virulence factor secreted by H. pylori, even in the absence of ultrasound. When coupled with ultrasound exposure, it inactivates H. pylori by generating reactive oxygen species, offering a potential solution to overcome antimicrobial resistance. In female mouse models bearing H. pylori infection, this sonodynamic therapy performs comparably to the standard triple therapy in reducing gastric infection. Significantly, unlike the antibiotic treatments, the sonodynamic therapy does not negatively disrupt gut microbiota, with the only major impact being upregulation of Lactobacillus, which is a bacterium widely used in yogurt products and probiotics. This study presents a promising alternative to the current antibiotic-based therapies for H. pylori infection, offering a reduced risk of antimicrobial resistance and minimal disturbance to the gut microbiota.


Assuntos
Microbioma Gastrointestinal , Infecções por Helicobacter , Helicobacter pylori , Feminino , Animais , Camundongos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Lecitinas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
5.
Angew Chem Int Ed Engl ; 63(2): e202314408, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37968240

RESUMO

Aiming to improve the photocatalytic activity in N2 fixation to produce ammonia, herein, we proposed a photochemical strategy to fabricate defects, and further deposition of Ru single atoms onto UiO-66 (Zr) framework. Electron-metal-support interactions (EMSI) were built between Ru single atoms and the support via a covalently bonding. EMSI were capable of accelerating charge transfer between Ru SAs and UiO-66, which was favorable for highly-efficiently photocatalytic activity. The photocatalytic production rate of ammonia improved from 4.57 µmol g-1 h-1 to 16.28 µmol g-1 h-1 with the fabrication of defects onto UiO-66, and further to 53.28 µmol g-1 h-1 with Ru-single atoms loading. From the DFT results, it was found that d-orbital electrons of Ru were donated to N2 π✶-antibonding orbital, facilitating the activation of the N≡N triple bond. A distal reaction pathway was probably occurred for the photocatalytic N2 reduction to ammonia on Ru1 /d-UiO-66 (single Ru sites decorated onto the nodes of defective UiO-66), and the first step of hydrogenation of N2 was the reaction determination step. This work shed a light on improving the photocatalytic activity via feasibly anchoring single atoms on MOF, and provided more evidences to understand the reaction mechanism in photocatalytic reduction of N2 .

6.
ACS Appl Mater Interfaces ; 15(50): 59075-59086, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38051973

RESUMO

Fog harvesting plays a pivotal role in harnessing atmospheric water resources and holds significant promise for alleviating global water scarcity. Nonetheless, enhancing harvesting efficiency remains a persistent challenge, especially concerning the rapid detachment of droplets from surfaces. In this study, we discovered that the trichomes of Sarracenia not only efficiently harvest and transport liquid but also quickly drain harvested liquid. We have elucidated the augmentation mechanism behind effective fog harvesting and drainage within the lid of Sarracenia. The trichomes facing the counterflow can enhance fog harvesting efficiency by 80% through air-flow-assisted spreading of liquid film. The wedge corner generated by the interface between hydrophilic and hydrophobic surfaces, coupled with the reduction of cross-sectional angles, diminishes the adhesive force of liquid droplets, fosters droplet spheroidization, and substantially facilitates droplet detachment. In addition, the quantitative detachment of droplets can be achieved by adjusting the cross-sectional angle and wetting gradient. This integrated structure combining efficient condensation and detachment has diverse applications in cooling towers and seawater desalination.

7.
Nat Commun ; 14(1): 7384, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968267

RESUMO

Spinal muscular atrophy is an autosomal recessive neuromuscular disease caused by mutations in the multifunctional protein Survival of Motor Neuron, or SMN. Within the nucleus, SMN localizes to Cajal bodies, which are associated with nucleoli, nuclear organelles dedicated to the first steps of ribosome biogenesis. The highly organized structure of the nucleolus can be dynamically altered by genotoxic agents. RNAP1, Fibrillarin, and nucleolar DNA are exported to the periphery of the nucleolus after genotoxic stress and, once DNA repair is fully completed, the organization of the nucleolus is restored. We find that SMN is required for the restoration of the nucleolar structure after genotoxic stress. During DNA repair, SMN shuttles from the Cajal bodies to the nucleolus. This shuttling is important for nucleolar homeostasis and relies on the presence of Coilin and the activity of PRMT1.


Assuntos
Atrofia Muscular Espinal , Proteínas de Ligação a RNA , Humanos , Proteínas de Ligação a RNA/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Nucléolo Celular/metabolismo , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/metabolismo , Neurônios Motores/metabolismo , Proteínas do Complexo SMN/metabolismo , Corpos Enovelados/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo
8.
ACS Nano ; 17(14): 13724-13733, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37403892

RESUMO

Ice accumulation on surfaces significantly jeopardizes the operational security and economic effectiveness of equipment. As one of the efficient anti-icing strategies, fracture-induced ice detachment strategy can realize low ice adhesion strength and is feasible for large-area anti-icing, but its application in harsh environment is restrained by mechanical robustness deterioration due to ultralow elastic moduli. It is still a challenge for fracture-promoted interfaces to reach ultralow ice adhesion and maintain strong mechanical robustness. Drawing inspiration from subcutaneous tissue, we propose a multiscale interpenetrating reinforcing method to develop a fracture-promoted ultraslippery ice detachment interface. Our approach minimizes elastic deformation and the stress threshold of fracture initiation during ice detachment, ensuring fast and noninjurious ice detachment on the interface. At the same time, this method reinforces the mechanical robustness of the fracture-promoted ultraslippery interface, making it possible to ensure long-term operation under harsh conditions. The superiority is revealed by ultralow ice adhesion strength below 20 kPa at -30 °C even after 200 continuous abrasion cycles, as well as efficient ice shedding during dynamic anti-icing tests, which is clarified by theoretical prediction and experimental verification. This work is expected to enlighten the design of next-generation durable anti-icing interface.

9.
Chem Commun (Camb) ; 59(29): 4274-4287, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36942529

RESUMO

Bismuth-based semiconductors (BBSs) with their typical layered structures and unique electronic properties are considered an attractive visible light-responsive photocatalysts. Recently, BBS exhibited promising properties and was rapidly developed in photoreduction reactions. In this review, we firstly focus on the photoreduction reactions of BBS with a description of the basic principles. Specifically, the restrictive factors of the photoreduction reactions and the design directions of the catalysts are addressed. BBS photocatalysts, such as bismuth oxide, bismuth halide oxide and bismuth-based oxygenates, are presented in terms of the catalyst material design, crystal structure and other features. Furthermore, the primary applications of BBS in photoreduction reactions are described, including CO2 reduction, N2 reduction, H2 evolution, and nitrate reduction. Additionally, the advances and shortages of BBS applied in these processes are summarized and comprehensively discussed. Future works for BBS applied in photoreduction processes are also proposed.

10.
Dev Comp Immunol ; 128: 104321, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34798199

RESUMO

MDM2 (mouse double-minute) and p53 form a negative feedback loop and play a prominent role in preventing the induction of uncontrolled apoptosis. To better understand their potential roles in oyster Crassostrea hongkongensis, MDM2 and p53 homologs were first isolated and cloned in C. hongkongensis (named ChMDM2 and Chp53), and their mRNA expression patterns in tissues and developmental stages were analyzed. Multiple sequence alignment analysis and phylogenetic analysis of ChMDM2 and Chp53 displayed a high degree of homology and conservation. In addition, exposure to Vibrio coralliilyticus resulted in DNA damage and apoptosis in the hemocytes of C. hongkongensis, and found that the mRNA expression level of ChMDM2 was decreased, while the relative expression of Chp53 was significantly increased in the hemocytes and gills. Furthermore, fluorescence from ChMDM2-EGFP and Chp53-Red were found to be distributed in the nucleus of HEK293T cells. Besides, dual-luciferase reporter assays showed that ChMDM2 antagonized with Chp53 and participates in p53 signaling pathway. In addition, the interaction between ChMDM2 and Chp53 was confirmed strongly by Co-immunoprecipitation assays. Furthermore, the results of RNAi showed that ChMDM2 and Chp53 participated in apoptosis which induced infection of V. coralliilyticus. Taken together, our results characterized the features of ChMDM2 and Chp53, which played a critical role in apoptosis of C. hongkongensis.


Assuntos
Crassostrea , Proteína Supressora de Tumor p53 , Animais , Células HEK293 , Hemócitos , Humanos , Imunidade , Imunidade Inata/genética , Camundongos , Filogenia , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
11.
PLoS One ; 15(4): e0231399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32276269

RESUMO

Vibrio coralliilyticus is a pathogen of coral and mollusk, contributing to dramatic losses worldwide. In our study, we found that V. coralliilyticus challenge could directly affect adult Tridacna crocea survival; there were dead individuals appearing at 6 h post infection, and there were 45.56% and 56.78% mortality rates in challenged groups after 36 h of infection. The apoptosis rate of hemocytes was significantly increased by 1.8-fold at 6 h after V. coralliilyticus injection. To shed light on the mechanistic molecular responses of T. crocea to V. coralliilyticus infection, we used transcriptome sequencing analysis and other relevant techniques to analyze T. crocea hemocytes at 0 h, 6 h, 12 h and 24 h after V. coralliilyticus challenge. Our results revealed that the total numbers of unigenes and DEGs were 195651 and 3446, respectively. Additional details were found by KEGG pathway enrichment analysis, where DEGs were significantly enriched in immune-related signaling pathways, such as the TLR signaling pathway, and some were associated with signaling related to apoptosis. Quantitative validation results illustrated that with exposure to V. coralliilyticus, the expression of TLR pathway members, TLR, MyD88, IRAK4, TRAF6, and IкB-α, were significantly upregulated (by 22.9-, 9.6-, 4.0-, 3.6-, and 3.9-fold, respectively) at 6 h. The cytokine-related gene IL-17 exhibited an increase of 6.3-fold and 10.5-fold at 3 h and 6 h, respectively. The apoptosis-related gene IAP1 was dramatically increased by 2.99-fold at 6 h. These results indicate that adult T. crocea could initiate the TLR pathway to resist V. coralliilyticus, which promotes the release of inflammatory factors such as IL-17 and leads to the activation of a series of outcomes, such as apoptosis. The response mechanism is related to the T. crocea immunoreaction stimulated by V. coralliilyticus, providing a theoretical basis for understanding T. crocea immune response mechanisms.


Assuntos
Bivalves/imunologia , Transcriptoma , Vibrio/patogenicidade , Animais , Bivalves/genética , Bivalves/microbiologia , Citocinas/genética , Citocinas/metabolismo , Hemócitos/metabolismo , Hemócitos/microbiologia , Imunidade Inata , Transdução de Sinais , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
12.
Fish Shellfish Immunol ; 98: 122-129, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31917320

RESUMO

Caspase 3 plays an important role in apoptotic pathways and contributes to maintaining the homeostasis of the immune system in organisms. The structure, functions, and characteristics of caspase 3 have been extensively investigated in many species, but the research is scarce when it comes to bivalves, particularly oysters. In this study, we identified and cloned a previously unknown caspase 3 gene, named ChCas 3, in C. hongkongensis. The full-length cDNA of ChCas 3 was 1562 bp and included a 175 bp 5'-untranslated region (UTR), a 141 bp 3'-UTR and a 1245 bp open reading frame (ORF) that encoded a polypeptide of 415 amino acids. Similar to caspase 3 in other species, ChCas 3 has a pro-domain, a conserved cysteine active site, a large p20 subunit and a small p10 subunit. Our findings demonstrated the expression of ChCas 3 in all the eight tissues via tissue-specific expression assays with the highest expression in haemocytes. ChCas 3 was confirmed to be expressed throughout the larval development stages, and fluorescence from pEGFP-N1-ChCas 3 was found to be distributed throughout the entire HEK293T cell. In addition, the relative expression of ChCas 3 significantly enhanced in hemocytes post bacterial stimulation, and overexpression of ChCas 3 led to upregulation of the transcriptional activity of NF-κB and p53 reporter genes in HEK293T cells, which indicated that it was involved in innate immune responses. Finally, the apoptosis rate of the haemocytes declined considerably compared with that of the control group after the expression of ChCas 3 was successfully silenced by dsRNA, corroborating its sentinel role in apoptosis. This study provides comprehensive underpinning evidences, affirming caspase 3 crucial role against bacterial infection and apoptosis in C. hongkongensis.


Assuntos
Apoptose/genética , Caspase 3/genética , Caspase 3/imunologia , Crassostrea/genética , Crassostrea/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Animais , Células HEK293 , Hemócitos/metabolismo , Humanos
13.
Artigo em Inglês | MEDLINE | ID: mdl-30533645

RESUMO

We are reporting the sequences of seven complete genomes of parvovirus B19, which were extracted from human plasma specimens collected in the United States. The seven B19 genome sequences, which are 5,596 nucleotides long and include the inverted terminal repeats (ITRs), share an identity of 96.73%. Their ITRs can be grouped into two types that have two nucleotide mutations between each other.

14.
Appl Microbiol Biotechnol ; 102(18): 7997-8009, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29959464

RESUMO

Morels are some of the most highly prized edible and medicinal mushrooms, and the outdoor cultivation has been achieved in China in recent years. Sclerotial formation is one of the most important phases during the morel life cycle, and the number of sclerotia indicates the spawn quality during cultivation. However, the sclerotial formation and differentiation mechanisms are poorly understood. In this study, the sclerotial formation process of Morchella importuna and the effects of reactive oxygen species on scerotial formation were studied. Scerotial formation was defined as five distinctive phases, hypha early, hyphal growth, sclerotial initiation, development, and maturation. The mycelia in the sclerotium-forming area were swollen, darkened, and dense with sclerotial formation, but hydrogen peroxide accumulated in the region lacking sclerotial formation. The expression of all six genes for superoxide dismutases tested increased with sclerotial maturation. A difference in hydrogen peroxide concentration of 20 mM could promote the sclerotial initiation and induce expression of sod genes. The MAPK signaling pathway was activated, and they passed the signal from an area of high oxidative stress to a low area to initiate sclerotial formation. An understanding of the sclerotial formation mechanisms in M. importuna may help to understand the life cycle and facilitate the fruiting body cultivation.


Assuntos
Ascomicetos/metabolismo , Hifas/crescimento & desenvolvimento , Espécies Reativas de Oxigênio/metabolismo , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , China , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Peróxido de Hidrogênio/metabolismo , Hifas/genética , Hifas/metabolismo , Micélio/genética , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Estresse Oxidativo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
15.
Sci Rep ; 7(1): 14722, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29116123

RESUMO

Frost accretion on surfaces may cause severe problems and the high-efficiency defrosting methods are still urgently needed in many application fields like heat transfer, optical and electric power system, etc. In this study, a nano-needle superhydrophobic surface is prepared and the frosting/defrosting experiments are conducted on it. Three steps are found in the defrosting process: melting frost shrinking and splitting, instantaneous self-triggered deforming followed by deformation-induced movements (namely, in-situ shaking, rotating, rolling, and self-jumping). The self-jumping performance of the melting frost is extremely fascinating and worth studying due to its capability of evidently shortening the defrosting process and reducing (even avoiding) residual droplets after defrosting. The study on the melting frost self-jumping phenomena demonstrates that the kinetic energy transformed from instantaneous superficial area change in self-triggered deforming step is the intrinsic reason for various melting frost self-propelled movements, and when the transformed energy reaches a certain amount, the self-jumping phenomena occur. And some facilitating conditions for melting frost self-jumping phenomena are also discussed. This work will provide an efficient way for defrosting or an inspiration for further research on defrosting.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(7): 1869-77, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-23016343

RESUMO

MERSI is the keystone payload of FengYun-3 and there have been two sensors operating on-orbit since 2008. The on-orbit response changes obviously at reflective solar bands (RSBs) and must be effectively monitored and corrected. However MERSI can not realize the RSBs onboard absolute radiometric calibration. This paper presents a new vicarious calibration (VC) method for RSBs based on in-situ BRDF model, and vector radiometric transfer model 6SV with gaseous absorption correction using MOTRAN. The results of synchronous VC experiments in 4 years show that the calibration uncertainties are within 5% except for band at the center of water vapor absorption, and 3% for most bands. Aqua MODIS was taken as the radiometric reference to evaluate the accuracy of this VC method. By comparison of the simulated radiation at top of atmosphere (TOA) with MODIS measurement, it was revealed that the average relative differences are within 3% for window bands with wavelengths less than 1 microm, and 5% for bands with wavelengths larger than 1 microm (except for band 7 at 2.1 microm). Besides, the synchronous nadir observation cross analysis shows the excellent agreement between re-calibrated MERSI TOA apparent reflectance and MODIS measurements. Based on the multi-year site calibration results, it was found that the calibration coefficients could be fitted with two-order polynomials, thus the daily calibration updates could be realized and the response variation between two calibration experiments could be corrected timely; there are large response changes at bands with wavelengths less than 0.6 microm, the degradation rate of the first year at band 8 (0.41 microm) is about 14%; the on-orbit response degradation is maximum at the beginning, the degradation rates slow down after one year in operation, and after two years the responses even increase at some band with wavelengths larger than 0.6 microm.

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