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2.
Langmuir ; 39(46): 16618-16627, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37934203

RESUMO

Liquid marbles (LMs) are nonwetting droplets manufactured by encapsulating droplets with micro- or nanoscale particles. These marbles are widely used as transport carriers for digital microfluidics due to their rapid displacement velocity and leak-free transport. An improved understanding of the resistance mechanism of rolling LMs is crucial for their transport and manipulation. In this study, we investigated the rolling resistance of LMs obtained with different powders and volumes using a high-speed camera. Our findings suggest that the deformation of liquid marbles would hinder their rolling by a resistance torque. To depict this resistance effect, we propose a theoretical model (f∼λ(ε-12Bo1/2ε2+14Boε3)), where f is the rolling resistance of marbles, λ is the deflection coefficient, Bo is the Bond number, and (ε is the contact surface deformation) that accurately predicts the relationship between deformation and rolling resistance, which is supported by our experimental results. To further validate our theoretical model, we conducted three independent experiments: shape detection of prepared LMs, measuring the elastic force of LMs, and detecting the diffusive motion of the encapsulating particles. Furthermore, we discuss three factors that affect the rolling resistance: the volume of the marbles, the type and size of the encapsulating particles, and the substrate roughness. This comprehensive study not only generalizes the mechanism of deformation hindering the rolling of liquid marbles but also provides a theoretical framework to predict the relationship between the deformation and rolling resistance. These findings have practical implications for improving the manipulation efficiency and advancing the use of LMs as microfluidic carriers.

4.
Infect Dis Poverty ; 12(1): 20, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932414

RESUMO

BACKGROUND: Emerging fungal pathogens pose important threats to global public health. The World Health Organization has responded to the rising threat of traditionally neglected fungal infections by developing a Fungal Priority Pathogens List (FPPL). Taking the highest-ranked fungal pathogen in the FPPL, Cryptococcus neoformans, as a paradigm, we review progress made over the past two decades on its global burden, its clinical manifestation and management of cryptococcal infection, and its antifungal resistance. The purpose of this review is to drive research efforts to improve future diagnoses, therapies, and interventions associated with fungal infections. METHODS: We first reviewed trends in the global burden of HIV-associated cryptococcal infection, mainly based on a series of systematic studies. We next conducted scoping reviews in accordance with the guidelines described in the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for Scoping Reviews using PubMed and ScienceDirect with the keyword Cryptococcus neoformans to identify case reports of cryptococcal infections published since 2000. We then reviewed recent updates on the diagnosis and antifungal treatment of cryptococcal infections. Finally, we summarized knowledge regarding the resistance and tolerance of C. neoformans to approved antifungal drugs. RESULTS: There has been a general reduction in the estimated global burden of HIV-associated cryptococcal meningitis since 2009, probably due to improvements in highly active antiretroviral therapies. However, cryptococcal meningitis still accounts for 19% of AIDS-related deaths annually. The incidences of CM in Europe and North America and the Latin America region have increased by approximately two-fold since 2009, while other regions showed either reduced or stable numbers of cases. Unfortunately, diagnostic and treatment options for cryptococcal infections are limited, and emerging antifungal resistance exacerbates the public health burden. CONCLUSION: The rising threat of C. neoformans is compounded by accumulating evidence for its ability to infect immunocompetent individuals and the emergence of antifungal-resistant variants. Emphasis should be placed on further understanding the mechanisms of pathogenicity and of antifungal resistance and tolerance. The development of novel management strategies through the identification of new drug targets and the discovery and optimization of new and existing diagnostics and therapeutics are key to reducing the health burden.


Assuntos
Cryptococcus neoformans , Infecções por HIV , Meningite Criptocócica , Micoses , Humanos , Meningite Criptocócica/tratamento farmacológico , Meningite Criptocócica/epidemiologia , Meningite Criptocócica/complicações , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Micoses/complicações , Micoses/tratamento farmacológico
5.
Langmuir ; 39(14): 5179-5186, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36989060

RESUMO

When a droplet contacts a solid surface, the liquid spreads over the solid surface to minimize the total surface energy. This phenomenon is widespread in industrial production and nature, so research on droplet spreading is of great significance. Here, the adhesion force and the spreading radius during droplet spreading can be quantified using a highly sensitive photoelectric method. It is possible to study droplet spreading from two dimensions at the microscale. The adhesion force is measured by an optical lever, and the spreading radius is measured by an ultrafast electrical method. The measurement method allows the force resolution and the space-time resolution to reach the nanonewton lever and the nanosecond lever, respectively. We obtain the maximum spreading radius and the maximum adhesion force during short-time spreading through our technique. Moreover, we numerically simulate the droplet spreading process through the lattice Boltzmann solver and confirm the observed results. This study provides a new experimental technique for studying droplet spreading dynamics from multiple perspectives, which can deepen our understanding of droplet spreading and provide guidance for the development of new techniques.

6.
Funct Integr Genomics ; 23(2): 104, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36976410

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) are well established to have an important role in cancer. The goal of this research was to investigate the prognostic usefulness of putative immune-related lncRNAs in hepatocellular carcinoma (HCC). METHODS: The developed lncRNA signature was validated using 343 HCC patients from The Cancer Genome Atlas (TCGA) and 81 samples from Gene Expression Omnibus (GEO). Cox regression and Least Absolute Shrinkage and Selection Operator (LASSO) analysis were used to analyze immune-related lncRNAs for HCC prognosis. Patients in the low-risk group survived substantially longer than those in the high-risk group (P < 0.05). The discovered signal might be a useful prognostic factor for predicting patient survival. Overall survival predicted some clinical net improvements, according to the nomogram. Numerous enrichment approaches (including gene set enrichment analysis) were utilized to investigate the underlying mechanisms. RESULTS: Drug metabolism, mTOR, and p53 signaling pathways were associated with high-risk groups. When the expression of lncRNA PRRT3-AS1 was silenced in HepG2 cells, the proliferation, migration, and invasion abilities of HepG2 cells were decreased, and apoptosis was enhanced. In the supernatant from HepG2 cells with PRRT3-AS1 knockdown, the anti-inflammatory factors IL-10 and TGF-1 were induced, whereas the pro-inflammatory factors IL-1ß, TNF-α, and IL-6 were reduced (P < 0.05). After PRRT3-AS1 knockdown, the protein expression of CD24, THY1, LYN, CD47, and TRAF2 in HepG2 cells was attenuated (P < 0.05). CONCLUSION: The discovery of five immune-related lncRNA signatures has significant therapeutic significance for predicting patient prognosis and directing personalized treatment for patients with HCC, which requires additional prospective confirmation.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/genética , RNA Longo não Codificante/genética , Estudos Prospectivos , Transcriptoma , Neoplasias Hepáticas/genética , Biomarcadores , Biomarcadores Tumorais/genética
7.
RSC Adv ; 12(24): 15296-15315, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35693225

RESUMO

Liquid marbles (LMs) are non-wettable droplets formed with a coating of hydrophobic particles. They can move easily across either solid or liquid surfaces since the hydrophobic particles protect the internal liquid from contacting the substrate. In recent years, mainly due to their simple preparation, abundant materials, non-wetting/non-adhesive properties, elasticities and stabilities, LMs have been applied in many fields such as microfluidics, sensors and biological incubators. In this review, the recent advances in the preparation, physical properties and applications of liquid marbles, especially operations and floating abilities, are summarized. Moreover, the challenges to achieve uniformity, slow volatilization and stronger stability are pointed out. Various applications generated by LMs' structural characteristics are also expected.

8.
Langmuir ; 38(22): 6923-6933, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35451848

RESUMO

Coalescence-induced droplet jumping has great prospects in many applications. Nevertheless, the applications are vastly limited by a low jumping velocity. Conventional methods to enhance the droplet coalescence jumping velocity are enabled by protruding structures with superhydrophobic surfaces. However, the jumping velocity improvement is limited by the height of protruding structures. Here, we present rationally designed limitation structures with superhydrophobic surfaces to achieve a dimensionless jumping velocity, Vj* ≈ 0.64. The mechanism of enhancing the jumping velocity is demonstrated through the study of numerical simulations and geometric parameters of limitation structures, providing guidelines for optimized structures. Experimental and numerical results indicate that the mechanism consists of the combined action of the velocity vectors' redirection and the Laplace pressure difference within deformed droplets trapped in limitation structures. On the basis of previous research on the mechanisms of protruding structures and our study, we successfully exploited those mechanisms to further improve the jumping velocity by combining the limitation structure with the protruding structure. Experimentally, we attained a dimensionless jumping velocity of Vj* ≈ 0.74 with an energy conversion efficiency of η ≈ 48%, breaking the jumping velocity limit. This work not only demonstrates a new mechanism for achieving a high jumping velocity and energy conversion efficiency but also sheds lights on the effect of limitation structures on coalescence hydrodynamics and elucidates a method to further enhance the jumping velocity based on protruding structures.

9.
R Soc Open Sci ; 9(1): 211632, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35242354

RESUMO

The measurement of the droplets' elasticity is vitally important in microfluidic and ink-jet printing. It refers to the ability of the droplet to restore its original shape and strong robustness. This study investigated a novel method to measure elasticity. The plate coated with super-hydrophobic layers pressed on a droplet and the elastic force was recorded by an electronic balance. Meanwhile, a mathematical model was constructed to calculate the changes of the droplet area under the force. The measurement showed that external work mainly converts into surface energy and the damping ratio increases from 0.068 to 0.261 with the increase of mass fraction from 0 to 80 wt%. It also indicates that the novel method can accurately and efficiently measure the elasticity of droplets.

10.
Artigo em Inglês | MEDLINE | ID: mdl-36612874

RESUMO

Teachers and students work and study in classrooms for long durations. The indoor environment directly affects the health and satisfaction of teachers and students. To explore the performance differences between green buildings, conventional buildings, and retrofitted buildings in terms of their indoor environment, occupant satisfaction, and sick building syndrome (SBS), as well as the correlation between these different aspects, three university teaching buildings were selected in hot summer and cold winter regions in China. These included a green building (GB), a retrofitted building (RB), and a conventional building (CB). Long-term indoor environment monitoring and point-to-point measurements were conducted during the transition season and winter and the indoor environment, satisfaction, and SBS in the three buildings were compared. A sample of 399 point-to-point questionnaires was collected. A subjective-objective indoor environmental quality (IEQ) evaluation model for schools in China was established, covering satisfaction and the indoor environment. The results showed that the compliance rate of the indoor environment in the GB and RB was generally superior to that of the CB. The overall satisfaction was the highest for the GB, followed by the CB, and then the RB. The GB had the highest overall indoor environment quality score, followed by the RB and then the CB. The occurrence of SBS was lowest in the CB, followed by the GB, and then the RB. It was determined that the design of natural ventilation should be improved and that building users should be given the right to autonomous window control and temperature control. To reduce the occurrence of SBS symptoms, attention should be paid to the control of temperature and CO2 concentration. To improve learning efficiency, it suggests reducing indoor CO2 concentrations and improving desktop illuminance. This study provides a reference for improving the indoor environment and health performance of existing university teaching buildings.


Assuntos
Poluição do Ar em Ambientes Fechados , Síndrome do Edifício Doente , Humanos , Síndrome do Edifício Doente/epidemiologia , Poluição do Ar em Ambientes Fechados/análise , Estações do Ano , Universidades , Dióxido de Carbono/análise , Satisfação Pessoal
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-920480

RESUMO

@#[摘 要] 目的:探讨lncRNA-Z38对胃癌细胞恶性生物学行为的影响及其可能的调控机制。方法:构建lncRNA-Z38稳定过表达的胃癌细胞系(AGS、MKN74细胞),通过细胞成球实验检测过表达lncRNA-Z38对胃癌细胞肿瘤特征的影响。对过表达lncRNA-Z38的AGS细胞及对照细胞进行高通量测序,对差异表达基因进行KEGG富集分析,筛选出可能参与调控胃癌发生发展的信号通路,采用WB等技术验证lncRNA-Z38通过调控该信号通路参与提高胃癌细胞的干性。结果:成功构建lncRNA-Z38过表达细胞株,细胞成球实验提示lncRNA-Z38过表达细胞的成球能力显著高于对照细胞(P<0.05)。通过测序筛选出lncRNA-Z38过表达胃癌细胞中的1 999个差异表达基因,其中上调基因1 238个、下调基因761个;经KEGG富集分析得到其中变化最显著的通路为TGF-β信号通路(P<0.05)。WB实验结果提示,lncRNA-Z38高表达胃癌细胞中TGF-β信号通路组成基因编码蛋白ID3、BMP6显著上调(均P<0.05)、GDF-5、WNT8B显著下调(P<0.05)。结论:在胃癌中高度表达的lncRNA-Z38通过调控TGF-β信号通路提高胃癌细胞的干性。

12.
Mater Sci Eng C Mater Biol Appl ; 57: 181-8, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26354253

RESUMO

The regeneration of functional skin remains elusive, due to poor engraftment, deficient vascularization, and excessive scar formation. Aiming to overcome these issues, the present study proposed the combination of a three-dimensional graphene foam (GF) scaffold loaded with bone marrow derived mesenchymal stem cells (MSCs) to improve skin wound healing. The GFs demonstrated good biocompatibility and promoted the growth and proliferation of MSCs. Meanwhile, the GFs loaded with MSCs obviously facilitated wound closure in animal model. The dermis formed in the presence of the GF structure loaded with MSCs was thicker and possessed a more complex structure at day 14 post-surgery. The transplanted MSCs correlated with upregulation of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), which may lead to neo-vascularization. Additionally, an anti-scarring effect was observed in the presence of the 3D-GF scaffold and MSCs, as evidenced by a downregulation of transforming growth factor-beta 1 (TGF-ß1) and alpha-smooth muscle actin (α-SMA) together with an increase of TGF-ß3. Altogether, the GF scaffold could guide the wound healing process with reduced scarring, and the MSCs were crucial to enhance vascularization and provided a better quality neo-skin. The GF scaffold loaded with MSCs possesses necessary bioactive cues to improve wound healing with reduced scarring, which may be of great clinical significance for skin wound healing.


Assuntos
Cicatriz/prevenção & controle , Grafite/química , Transplante de Células-Tronco Mesenquimais/métodos , Pele/lesões , Pele/patologia , Alicerces Teciduais , Animais , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Cicatriz/patologia , Gases/química , Células-Tronco Mesenquimais/patologia , Ratos , Técnicas de Fechamento de Ferimentos , Cicatrização/fisiologia
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