Journal articles: 'Liquid junction interface'

1

Lee, Joon-Hyung, Jeong-Joo Kim, Haifeng Wang, and Sang-Hee Cho. "Observation of Intergranular Films in BaB2O4-added BaTiO3 Ceramics." Journal of Materials Research 15, no. 7 (July 2000): 1600–1604. http://dx.doi.org/10.1557/jmr.2000.0229.

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Distribution characteristics of boundary phase in BaB2O4 added BaTiO3 ceramics were investigated with a focus on the curvature difference of solid–liquid interfaces at two-grain and triple junctions. High-resolution transmission electron microscopy revealed that the triple junction of solid grains showed the positive curvature of solid–liquid interface and consisted of the mixture of liquid phase and crystallized BaB2O4 phase. On the other hand, flat amorphous thin film of 2.5-nm thickness was observed at the two-grain junction. This kind of boundary phase distribution characteristic was explained by the solubility difference between two kinds of junctions of solid grains that had different curvature of solid–liquid interfaces.

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Bokstein, Boris S., S. A. Gulevsky, A. L. Petelin, and A. O. Rodin. "Diffusion Controlled Grain Triple Junctions Wetting in Metals." Defect and Diffusion Forum 309-310 (March 2011): 231–38. http://dx.doi.org/10.4028/www.scientific.net/ddf.309-310.231.

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The interaction between liquid and solid metals where the liquid-solid interface contains three grain boundary lines which meet in triple junction point is considered. The assumption that the liquid grooves may be formed not only along grain boundaries but along triple junctions is presented. The variation of Gibbs energy during the formation of triangle pyramidal groove along triple junction is determined. The dependence of Gibbs energy variation from groove dimensions shows that the wetting of triple junctions occurs by lower temperatures than the wetting of grain boundaries. This result allows to take into account the existence of grain size effect on the liquid phase penetration depth into the polycrystalline sample. The proposed mechanism of wetting in polycrystalline metal contains two stages: the outstrip melt penetration along triple junctions and the liquid grooving on grain boundaries forming the triple junctions. One of the processes – triple junction diffusion or liquid diffusion – may control the wetting in the polycrystalline sample.

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Storaska, Garrett A., and James M. Howe. "In-Situ TEM Investigation of the Solid/Liquid Interface in Al-Si Alloys." Microscopy and Microanalysis 6, S2 (August 2000): 1068–69. http://dx.doi.org/10.1017/s1431927600037831.

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The solid/liquid interface is a junction between two condensed phases with completely different atomic arrangements. At the interface between the periodically ordered solid and the amorphous liquid, the atoms adopt a structure that minimizes the excess energy due to the abrupt change between the surrounding phases. Faceted and diffuse interfaces describe two extremes in morphology of a solid/liquid interface. In a faceted interface, the change from solid to liquid occurs over one atomic layer, however periodic order extends into the first few liquid layers adjacent to the crystalline solid, as predicted by numerous models.1 The faceted interface advances by nucleation and growth of ledges on the interface. A diffuse interface has a structure in which the change from solid to liquid occurs over several atomic layers. This interface contains many ledges to which liquid atoms may attach continuously as the interface advances.

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Howe, James M., and Hiroyasu Saka. "In Situ Transmission Electron Microscopy Studies of the Solid–Liquid Interface." MRS Bulletin 29, no. 12 (December 2004): 951–57. http://dx.doi.org/10.1557/mrs2004.266.

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AbstractIn situtransmission electron microscopy (TEM) studies allow one to determine the structure, chemistry, and kinetic behavior of solid–liquid (S–L) interfaces with subnanometer spatial resolution. This article illustrates some important contributions ofin situTEM to our understanding of S–L interfaces in Al-Si alloys and liquid In particles in Al and Fe matrices.Four main areas are discussed:ordering in the liquid at a S–L interface, compositional changes across the interface, the kinetics and mechanisms of interface migration, and the contact angles and equilibrium melting temperature of small particles.Results from these studies reveal that (1)partially ordered layers form in the liquid at a Si{111} S–L interface in an Al–Si alloy, (2)the crystalline and compositional changes occur simultaneously across an Al S–L interface, (3)the Al interface is diffuse and its growth can be followed at velocities of a fewnm/s at extremely low undercoolings, and (4)the melting temperature of In particles less than ~ 10 nm in diameter can be raised or lowered in Al or Fe, depending on the contact angle that the S–L interface makes at the three-phase junction. These results illustrate the benefits of in situ TEM for providing fundamental insight into the mechanisms that control the behavior of S–L interfaces in materials.

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Berne, A., C. Kahanda, and O. Popovych. "An Improved Equation for the Liquid Junction Potential at the Interface of Different Solvents." Australian Journal of Chemistry 45, no. 10 (1992): 1633. http://dx.doi.org/10.1071/ch9921633.

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The component of the liquid-junction potential due to the diffusion of ions across an interface of electrolyte solutions in different solvents was formulated by taking into account the solvent dependence of the transport numbers, t, and of the chemical potentials of ions in the interphase region as determined from experimental data on their variation in the mixed-solvent compositions. The new equation was applied to NaCl/NaCl and HCl/HCl junctions between water and methanol-water solvents over the entire solvent range. Significant differences between the results obtained with the new equation and the old formulation, which treated the transport numbers as solvent-independent, were observed only for the HCl junctions involving 90-100 wt % aqueous methanol, where tH exhibits a sharp minimum as a function of the solvent composition.

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Jussila, Matti, Kai Sinervo, Simo P. Porras, and Marja-Liisa Riekkola. "Modified liquid junction interface for nonaqueous capillary electrophoresis-mass spectrometry." Electrophoresis 21, no. 15 (September 1, 2000): 3311–17. http://dx.doi.org/10.1002/1522-2683(20000901)21:15<3311::aid-elps3311>3.0.co;2-n.

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Krenkova, Jana, Karel Kleparnik, Jakub Grym, Jaroslav Luksch, and Frantisek Foret. "Self-aligning subatmospheric hybrid liquid junction electrospray interface for capillary electrophoresis." ELECTROPHORESIS 37, no. 3 (September 29, 2015): 414–17. http://dx.doi.org/10.1002/elps.201500357.

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Wang, Rui-Jin, and Zhi-Hua Li. "Influence on droplet formation in the presence of nanoparticles in a microfluidic T-junction." Thermal Science 16, no. 5 (2012): 1429–32. http://dx.doi.org/10.2298/tsci1205429w.

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The droplet formation in the presence of nanoparticles was studied in a T-shaped microfluidic device numerically. Nanoparticles in continuous phase did not influence droplet formation dynamics obviously. Contrarily, the presence of nanoparticles in dispersed phase will influence evidently droplet formation dynamics, the possible reason is that the accumulation of nanoparticles at the liquid-liquid interface would cause the variation of interfacial tension and the anisotropy of nanoparticles? movement at interface. Discussions on microscopic mechanism of droplet formation in the presence of nanoparticles were carried out.

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D’Orazio, Giovanni, and Salvatore Fanali. "Pressurized nano-liquid–junction interface for coupling capillary electrochromatography and nano-liquid chromatography with mass spectrometry." Journal of Chromatography A 1317 (November 2013): 67–76. http://dx.doi.org/10.1016/j.chroma.2013.08.052.

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Garcia, Frederick, and Jack D. Henion. "Gel-filled capillary electrophoresis/mass spectrometry using a liquid junction ion spray interface." Analytical Chemistry 64, no. 9 (May 1992): 985–90. http://dx.doi.org/10.1021/ac00033a005.

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Hong, Wenjing, Hennie Valkenier, Gábor Mészáros, David Zsolt Manrique, Artem Mishchenko, Alexander Putz, Pavel Moreno García, Colin J. Lambert, Jan C. Hummelen, and Thomas Wandlowski. "An MCBJ case study: The influence of π-conjugation on the single-molecule conductance at a solid/liquid interface." Beilstein Journal of Nanotechnology 2 (October 18, 2011): 699–713. http://dx.doi.org/10.3762/bjnano.2.76.

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π-Conjugation plays an important role in charge transport through single molecular junctions. We describe in this paper the construction of a mechanically controlled break-junction setup (MCBJ) equipped with a highly sensitive log I–V converter in order to measure ultralow conductances of molecular rods trapped between two gold leads. The current resolution of the setup reaches down to 10 fA. We report single-molecule conductance measurements of an anthracene-based linearly conjugated molecule (AC), of an anthraquinone-based cross-conjugated molecule (AQ), and of a dihydroanthracene-based molecule (AH) with a broken conjugation. The quantitative analysis of complementary current–distance and current–voltage measurements revealed details of the influence of π-conjugation on the single-molecule conductance.

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12

SAHA, ARIJIT. "ELECTRON–ELECTRON INTERACTION EFFECTS ON TRANSPORT THROUGH MESOSCOPIC SUPERCONDUCTING HYBRID JUNCTIONS." International Journal of Modern Physics B 27, no. 21 (July 30, 2013): 1330015. http://dx.doi.org/10.1142/s0217979213300156.

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Effects due to the proximity of a superconductor has motivated a lot of research work in the last several decades both from theoretical and experimental point of view. In this review, we are going to describe the physics of systems containing normal metal-superconductor interface. Mainly we discuss transport properties through such hybrid structures. In particular, we describe the effects of electron–electron interaction on transport through such superconducting junction of multiple one-dimensional quantum wires. The latter can be described in terms of a non-Fermi liquid theory called Luttinger liquid. In this review, from the application point of view, we also demonstrate the possible scenarios for production of pure spin current and large tunneling magnetoresistance in such hybrid junctions and analyze the influence of electron–electron interaction on the stability of the production of pure spin current.

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Kouthouridis, Sonya, Julie Goepp, Carolina Martini, Elizabeth Matthes, John W. Hanrahan, and Christopher Moraes. "Oxygenation as a driving factor in epithelial differentiation at the air–liquid interface." Integrative Biology 13, no. 3 (March 2021): 61–72. http://dx.doi.org/10.1093/intbio/zyab002.

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Abstract Culture at the air–liquid interface is broadly accepted as necessary for differentiation of cultured epithelial cells towards an in vivo-like phenotype. However, air–liquid interface cultures are expensive, laborious and challenging to scale for increased throughput applications. Deconstructing the microenvironmental parameters that drive these differentiation processes could circumvent these limitations, and here we hypothesize that reduced oxygenation due to diffusion limitations in liquid media limits differentiation in submerged cultures; and that this phenotype can be rescued by recreating normoxic conditions at the epithelial monolayer, even under submerged conditions. Guided by computational models, hyperoxygenation of atmospheric conditions was applied to manipulate oxygenation at the monolayer surface. The impact of this rescue condition was confirmed by assessing protein expression of hypoxia-sensitive markers. Differentiation of primary human bronchial epithelial cells isolated from healthy patients was then assessed in air–liquid interface, submerged and hyperoxygenated submerged culture conditions. Markers of differentiation, including epithelial layer thickness, tight junction formation, ciliated surface area and functional capacity for mucociliary clearance, were assessed and found to improve significantly in hyperoxygenated submerged cultures, beyond standard air–liquid interface or submerged culture conditions. These results demonstrate that an air–liquid interface is not necessary to produce highly differentiated epithelial structures, and that increased availability of oxygen and nutrient media can be leveraged as important strategies to improve epithelial differentiation for applications in respiratory toxicology and therapeutic development.

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Luo, Lan, Tingting Zhang, Xin Zhang, Rongping Yun, Yanjun Lin, Bing Zhang, and Xu Xiang. "Enhanced Hydrogen Production from Ethanol Photoreforming by Site-Specific Deposition of Au on Cu2O/TiO2 p-n Junction." Catalysts 10, no. 5 (May 13, 2020): 539. http://dx.doi.org/10.3390/catal10050539.

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Hydrogen production by photoreforming of biomass-derived ethanol is a renewable way of obtaining clean fuel. We developed a site-specific deposition strategy to construct supported Au catalysts by rationally constructing Ti3+ defects inTiO2 nanorods and Cu2O-TiO2 p-n junction across the interface of two components. The Au nanoparticles (~2.5 nm) were selectively anchored onto either TiO2 nanorods (Au@TiO2/Cu2O) or Cu2O nanocubes (Au@Cu2O/TiO2) or both TiO2 and Cu2O (Au@TiO2/Cu2O@Au) with the same Au loading. The electronic structure of supported Au species was changed by forming Au@TiO2 interface due to the adjacent Ti3+ defects and the associated oxygen vacancies while unchanged in Au@Cu2O/TiO2 catalyst. The p-n junction of TiO2/Cu2O promoted charge separation and transfer across the junction. During ethanol photoreforming, Au@TiO2/Cu2O catalyst possessing both the Au@TiO2 interface and the p-n junction showed the highest H2 production rate of 8548 μmol gcat−1 h−1 under simulated solar light, apparently superior to both Au@TiO2 and Au@Cu2O/TiO2 catalyst. The acetaldehyde was produced in liquid phase at an almost stoichiometric rate, and C−C cleavage of ethanol molecules to form CH4 or CO2 was greatly inhibited. Extensive spectroscopic results support the claim that Au adjacent to surface Ti3+ defects could be active sites for H2 production and p-n junction of TiO2/Cu2O facilitates photo-generated charge transfer and further dehydrogenation of ethanol to acetaldehyde during the photoreforming.

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Klepárník, Karel, and Marek Otevřel. "Analyte transport in liquid junction nano-electrospray interface between capillary electrophoresis and mass spectrometry." ELECTROPHORESIS 31, no. 5 (March 2010): 879–85. http://dx.doi.org/10.1002/elps.200900544.

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Lochbaum, Robin, Carolin Schilpp, Lara Nonnenmacher, Manfred Frick, Paul Dietl, and Oliver H. Wittekindt. "Retinoic acid signalling adjusts tight junction permeability in response to air-liquid interface conditions." Cellular Signalling 65 (January 2020): 109421. http://dx.doi.org/10.1016/j.cellsig.2019.109421.

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D’Orazio, Giovanni, and Salvatore Fanali. "Coupling capillary electrochromatography with mass spectrometry by using a liquid-junction nano-spray interface." Journal of Chromatography A 1217, no. 25 (June 2010): 4079–86. http://dx.doi.org/10.1016/j.chroma.2009.11.004.

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18

Higgins, Gerard, Coral Fustero Torre, Jean Tyrrell, Paul McNally, Brian J. Harvey, and Valerie Urbach. "Lipoxin A4prevents tight junction disruption and delays the colonization of cystic fibrosis bronchial epithelial cells byPseudomonas aeruginosa." American Journal of Physiology-Lung Cellular and Molecular Physiology 310, no. 11 (June 1, 2016): L1053—L1061. http://dx.doi.org/10.1152/ajplung.00368.2015.

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The specialized proresolution lipid mediator lipoxin A4(LXA4) is abnormally produced in cystic fibrosis (CF) airways. LXA4increases the CF airway surface liquid height and stimulates airway epithelial repair and tight junction formation. We report here a protective effect of LXA4(1 nM) against tight junction disruption caused by Pseudomonas aeruginosa bacterial challenge together with a delaying action against bacterial invasion in CF airway epithelial cells from patients with CF and immortalized cell lines. Bacterial invasion and tight junction integrity were measured by gentamicin exclusion assays and confocal fluorescence microscopy in non-CF (NuLi-1) and CF (CuFi-1) bronchial epithelial cell lines and in primary CF cultures, grown under an air/liquid interface, exposed to either a clinical or laboratory strains of P. aeruginosa. LXA4delayed P. aeruginosa invasion and transepithelial migration in CF and normal bronchial epithelial cell cultures. These protective effects of LXA4were inhibited by the ALX/FPR2 lipoxin receptor antagonist BOC-2. LXA4prevented the reduction in mRNA biosynthesis and protein abundance of the tight junction protein ZO-1 and reduced tight junction disruption induced by P. aeruginsosa inoculation. In conclusion, LXA4plays a protective role in bronchial epithelium by stimulating tight junction repair and by delaying and reducing the invasion of CF bronchial epithelial cells by P. aeruginsosa.

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Pao, William, and Zeeshan Qadir Memon. "Numerical evaluation of separation efficiency in converging T-junction with slug flow." International Journal of Numerical Methods for Heat & Fluid Flow 30, no. 7 (November 4, 2019): 3515–34. http://dx.doi.org/10.1108/hff-07-2019-0524.

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Purpose Excessive liquid carryover in T-junction presents a serious operational issue in offshore production platform. Slug flow and diameter ratio of T-junction are considered as two major factors causing liquid carryover. Regular and reduced T-junction are being used as partial phase separator but their efficiency is low. Converging T-junction with two distinct diameters (primary and secondary) in branch arm is used to improve the phase separation efficiency. The motivation is to combine specific feature of regular and reduced T-junction to increase separation efficiency of existing T-junction without involving too much operational workover. The purpose of this paper is to numerically evaluate the separation efficiency of a converging T-junction design. The present model and its methodology was validated with in-house experimental data for 3 inches diameter flow loop. Design/methodology/approach The slug flow regime was simulated using incompressible Eulerian mixture model coupled with volume of fluid method to capture the dynamic gas-liquid interface. Findings The analyses concluded that T-junction with primary-secondary branch arm diameters combination of 1.0-0.5 and 0.67-0.40 managed to achieve 95 per cent separation efficiency. The research also confirmed that over reduction of T-junction secondary diameter ratio below 0.2 will lead to decrease in separation efficiency. Research limitations/implications The present research is limit to air/water two-phase flow but the general results should be applicable for wider application. Practical implications The proposed design limited excessive workover and installation for current and existing T-junction. Hence, cutting down installation cost while improving the separation efficiency. Social implications The present research resulted in higher separation efficiency, cutting down production down time and lead to operational cost saving. Originality/value The present research proposes an original and new T-junction design that can increase phase separation efficiency to over 90 per cent. The finding also confirmed that there is a limitation whereby smaller diameter ratio T-junction does not always resulted in better separation.

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Protasova, Svetlana, Olga A. Kogtenkova, and Boris B. Straumal. "Faceting of Σ3 Grain Boundaries in Al." Materials Science Forum 558-559 (October 2007): 949–54. http://dx.doi.org/10.4028/www.scientific.net/msf.558-559.949.

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The temperature dependence of the energy of various facets of twin GBs has been measured. For the investigation of GB faceting the Al bicrystals of 99.999% wt. purity were grown by the modified Bridgman technique. One grain in these bicrystals is semi-surrounded by another one. Bicrystals were coated with a layer of Sn–Al alloy and annealed at various temperatures. Contact angles at the junction of a GB and two solid/liquid interfaces have been measured. The ratios of GB energy to solid/liquid interface energy have been calculated. Using these data, the Wulff-Herring plots and GB phase diagrams were constructed. Three different crystallographic facets were observed for the coincidence GB. Two of them are stable at all studied temperatures, the third one becomes metastable below ~ 800K. In GBs with θ = 3° only one facet (symmetric twin GB) is stable.

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Li, Fu-An, Ju-Li Huang, Shang-Yu Shen, Che-Wei Wang, and Guor-Rong Her. "Development of a Liquid-Junction/Low-Flow Interface for Phosphate Buffer Capillary Electrophoresis Mass Spectrometry." Analytical Chemistry 81, no. 7 (April 2009): 2810–14. http://dx.doi.org/10.1021/ac802491y.

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Chikama, Katsumi, Kiyoharu Nakatani, and Noboru Kitamura. "Liquid-Junction Potential Dependence of the Electron Transfer Rate across a Single-Microdroplet/Water Interface." Chemistry Letters 25, no. 8 (August 1996): 665–66. http://dx.doi.org/10.1246/cl.1996.665.

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Fanali, Salvatore, Giovanni D'Orazio, Frantisek Foret, Karel Kleparnik, and Zeineb Aturki. "On-line CE-MS using pressurized liquid junction nanoflow electrospray interface and surface-coated capillaries." ELECTROPHORESIS 27, no. 23 (December 2006): 4666–73. http://dx.doi.org/10.1002/elps.200600322.

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Wayner, P. C., C. Y. Tung, M. Tirumala, and J. H. Yang. "Experimental Study of Evaporation in the Contact Line Region of a Thin Film of Hexane." Journal of Heat Transfer 107, no. 1 (February 1, 1985): 182–89. http://dx.doi.org/10.1115/1.3247376.

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The transport processes in the contact line region (junction of evaporating thin liquid film, vapor, and substrate) of stationary steady-state evaporating thin films of hexane with various bulk compositions were studied experimentally. The substrate temperature distribution and liquid film thickness profile were measured, analyzed, and compared with previous results on other systems. The results demonstrate that small changes in the bulk composition significantly alter the characteristics of the transport processes in the contact line region. The curvature gradient at the liquid-vapor interface is a strong function of evaporation rate and composition. Concentration and temperature gradients give interfacial shear stresses and flow patterns that enhance contact line stability.

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Wu, Huanming, and Keqi Tang. "Highly Sensitive and Robust Capillary Electrophoresis-Electrospray Ionization-Mass Spectrometry: Interfaces, Preconcentration Techniques and Applications." Reviews in Analytical Chemistry 39, no. 1 (August 11, 2020): 45–55. http://dx.doi.org/10.1515/revac-2020-0112.

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AbstractCapillary electrophoresis (CE) coupled with mass spectrometry (MS) through electrospray ionization (ESI) is a promising alternative technique to liquid chromatography-ESI-MS (LC-ESI-MS) due to its high separation efficiency and high detection sensitivity. A sensitive and robust interface is essential in CE-ESI-MS. Continued development of CE-ESI-MS interfaces in the last decade, including junction-at-the-tip interfaces and sheathless interfaces, has improved the sensitivity and robustness of CE-ESI-MS significantly. The limited loading capacity of CE, one of major reasons that limits the utility of CE as a routine separation method, has also been addressed effectively by the use of in-capillary sample preconcentration techniques, such as transient CITP/CZE and dynamic pH junction. CE-ESI-MS could yield higher sensitivity as compared with the conventional LC-ESI-MS, and, therefore, is capable of identifying more proteins and peptides when the sample amount is very limited, such as single cell analysis. To improve the protein sequence coverage, CE-ESI-MS can also be used as a complementary technique to LC-ESI-MS, or combined with reversed phase LC to form a two dimensional separation technique. CE-ESI-MS is also effective in quantifying targeted peptides/proteins in complex bio-matrix.

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Chang, Shu-Han, Ping-Liang Ko, Wei-Hao Liao, Chien-Chung Peng, and Yi-Chung Tung. "Transwell Insert-Embedded Microfluidic Devices for Time-Lapse Monitoring of Alveolar Epithelium Barrier Function under Various Stimulations." Micromachines 12, no. 4 (April 6, 2021): 406. http://dx.doi.org/10.3390/mi12040406.

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This paper reports a transwell insert-embedded microfluidic device capable of culturing cells at an air-liquid interface (ALI), mimicking the in vivo alveolar epithelium microenvironment. Integration of a commercially available transwell insert makes the device fabrication straightforward and eliminates the tedious device assembly processes. The transwell insert can later be detached from the device for high-resolution imaging of the cells. In the experiments, the cells showing type-I pneumocyte markers are exploited to construct an in vitro alveolar epithelium model, and four culture conditions including conventional liquid/liquid culture (LLC) and air–liquid interface (ALI) cell culture in normal growth medium, and ALI cell culture with inflammatory cytokine (TNF-α) stimulation and ethanol vapor exposure are applied to investigate their effects on the alveolar epithelium barrier function. The barrier permeability is time-lapse monitored using trans-epithelial electrical resistance (TEER) measurement and immunofluorescence staining of the tight junction protein (ZO-1). The results demonstrate the functionalities of the device, and further show the applications and advantages of the constructed in vitro cell models for the lung studies.

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Molina, Samuel A., Brandon Stauffer, Hannah K. Moriarty, Agnes H. Kim, Nael A. McCarty, and Michael Koval. "Junctional abnormalities in human airway epithelial cells expressing F508del CFTR." American Journal of Physiology-Lung Cellular and Molecular Physiology 309, no. 5 (September 1, 2015): L475—L487. http://dx.doi.org/10.1152/ajplung.00060.2015.

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Cystic fibrosis (CF) has a profound impact on airway physiology. Accumulating evidence suggests that intercellular junctions are impaired in CF. We examined changes to CF transmembrane conductance regulator (CFTR) function, tight junctions, and gap junctions in NuLi-1 (CFTRwt/wt) and CuFi-5 (CFTRΔF508/ΔF508) cells. Cells were studied at air-liquid interface (ALI) and compared with primary human bronchial epithelial cells. On the basis of fluorescent lectin binding, the phenotype of the NuLi-1 and CuFi-5 cells at week 8 resembled that of serous, glycoprotein-rich airway cells. After week 7, CuFi-5 cells possessed 130% of the epithelial Na+ channel activity and 17% of the CFTR activity of NuLi-1 cells. In both cell types, expression levels of CFTR were comparable to those in primary airway epithelia. Transepithelial resistance of NuLi-1 and CuFi-5 cells stabilized during maturation in ALI culture, with significantly lower transepithelial resistance for CuFi-5 than NuLi-1 cells. We also found that F508del CFTR negatively affects gap junction function in the airway. NuLi-1 and CuFi-5 cells express the connexins Cx43 and Cx26. While both connexins were properly trafficked by NuLi-1 cells, Cx43 was mistrafficked by CuFi-5 cells. Cx43 trafficking was rescued in CuFi-5 cells treated with 4-phenylbutyric acid (4-PBA), as assessed by intracellular dye transfer. 4-PBA-treated CuFi-5 cells also exhibited an increase in forskolin-induced CFTR-mediated currents. The Cx43 trafficking defect was confirmed using IB3-1 cells and found to be corrected by 4-PBA treatment. These data support the use of NuLi-1 and CuFi-5 cells to examine the effects of F508del CFTR expression on tight junction and gap junction function in the context of serous human airway cells.

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Wachs, Timothy, Robin L. Sheppard, and Jack Henion. "Design and applications of a self-aligning liquid junction-electrospray interface for capillary electrophoresis-mass spectrometry." Journal of Chromatography B: Biomedical Sciences and Applications 685, no. 2 (October 1996): 335–42. http://dx.doi.org/10.1016/s0378-4347(96)00176-4.

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Kusý, Petr, Karel Klepárník, Zeineb Aturki, Salvatore Fanali, and František Foret. "Optimization of a pressurized liquid junction nanoelectrospray interface between CE and MS for reliable proteomic analysis." ELECTROPHORESIS 28, no. 12 (June 2007): 1964–69. http://dx.doi.org/10.1002/elps.200600640.

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Hsueh, Yun-Hung, Ju-Li Huang, Mei-Chun Tseng, and Guor-Rong Her. "Sensitivity improvement of CE/ESI/MS analysis of gangliosides using a liquid-junction/low-flow interface." ELECTROPHORESIS 31, no. 7 (April 2010): 1138–43. http://dx.doi.org/10.1002/elps.200900521.

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Reinhoud, N. J., W. M. A. Niessen, U. R. Tjaden, L. G. Gramberg, E. R. Verheij, and J. van der Greef. "Performance of a liquid-junction interface for capillary electrophoresis mass spectrometry using continuous-flow fast-atom bombardment." Rapid Communications in Mass Spectrometry 3, no. 10 (October 1989): 348–51. http://dx.doi.org/10.1002/rcm.1290031009.

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Liu, Yi-Lin, Nan-Hsuan Wang, Fu-An Li, and Guor-Rong Her. "A liquid-junction/low-flow interface for sensitivity improvement in micelle electrokinetic chromatography–electrospray ionization-mass spectrometry." Journal of Chromatography A 1216, no. 49 (December 2009): 8671–75. http://dx.doi.org/10.1016/j.chroma.2009.10.049.

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Stewart, Ceri E., Elizabeth E. Torr, Nur H. Mohd Jamili, Cynthia Bosquillon, and Ian Sayers. "Evaluation of Differentiated Human Bronchial Epithelial Cell Culture Systems for Asthma Research." Journal of Allergy 2012 (January 11, 2012): 1–11. http://dx.doi.org/10.1155/2012/943982.

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The aim of the current study was to evaluate primary (human bronchial epithelial cells, HBEC) and non-primary (Calu-3, BEAS-2B, BEAS-2B R1) bronchial epithelial cell culture systems as air-liquid interface- (ALI-) differentiated models for asthma research. Ability to differentiate into goblet (MUC5AC+) and ciliated (β-Tubulin IV+) cells was evaluated by confocal imaging and qPCR. Expression of tight junction/adhesion proteins (ZO-1, E-Cadherin) and development of transepithelial electrical resistance (TEER) were assessed. Primary cells showed localised MUC5AC, β-Tubulin IV, ZO-1, and E-Cadherin and developed TEER with, however, a large degree of inter- and intradonor variation. Calu-3 cells developed a more reproducible TEER and a phenotype similar to primary cells although with diffuse β-Tubulin IV staining. BEAS-2B cells did not differentiate or develop tight junctions. These data highlight the challenges in working with primary cell models and the need for careful characterisation and selection of systems to answer specific research questions.

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Liu, Chuanliang, and Swati S. Verma. "Direct coupling of ionic high-performance liquid chromatography with electrospray ionization mass spectrometry utilizing a microdialysis junction interface." Journal of Chromatography A 835, no. 1-2 (March 1999): 93–104. http://dx.doi.org/10.1016/s0021-9673(98)01069-3.

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Qian, Jin-yuan, Min-rui Chen, Zan Wu, Zhi-jiang Jin, and Bengt Sunden. "Effects of a Dynamic Injection Flow Rate on Slug Generation in a Cross-Junction Square Microchannel." Processes 7, no. 10 (October 18, 2019): 765. http://dx.doi.org/10.3390/pr7100765.

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The injection flow rates of two liquid phases play a decisive role in the slug generation of the liquid-liquid slug flow. However, most injection flow rates so far have been constant. In order to investigate the effects of dynamic injection flow rates on the slug generation, including the slug size, separation distance and slug generation cycle time, a transient numerical model of a cross-junction square microchannel is established. The Volume of Fluid method is adopted to simulate the interface between two phases, i.e., butanol and water. The model is validated by experiments at a constant injection flow rate. Three different types of dynamic injection flow rates are applied for butanol, which are triangle, rectangular and sine wave flow rates. The dynamic injection flow rate cycles, which are related to the constant slug generation cycle time t0, are investigated. Results show that when the cycle of the disperse phase flow rate is larger than t0, the slug generation changes periodically, and the period is influenced by the cycle of the disperse phase flow rate. Among the three kinds of dynamic disperse flow rate, the rectangular wave influences the slug size most significantly, while the triangle wave influences the separation distance and the slug generation time more prominently.

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Sejil, Selsabil, Farah Laariedh, Mihai Lazar, Davy Carole, Christian Brylinski, Dominique Planson, Gabriel Ferro, Christophe Raynaud, and Hervé Morel. "VLS Grown 4H-SiC Buried P⁺ Layers for JFET Lateral Structures." Materials Science Forum 821-823 (June 2015): 789–92. http://dx.doi.org/10.4028/www.scientific.net/msf.821-823.789.

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Lateral JFET transistors have been fabricated with N and P-type channels tentatively integrated monolithically on the same SiC wafer. Buried P+SiC layers grown by Vapor-Liquid-Solid (VLS) selective epitaxy were utilized as source and drain for the P-JFET and as gate for the N-JFET. The ohmicity of the contacts, both on VLS grown P+and ion implanted N+layers, has been confirmed by Transfer Length Method (TLM) measurements. A premature leakage current is observed on the P/N junction created directly by the P+VLS gate layer, probably due to imperfect VLS (P+) / CVD (N+) SiC interface.

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Wu, Liping, Tadayuki Oshima, Min Li, Toshihiko Tomita, Hirokazu Fukui, Jiro Watari, and Hiroto Miwa. "Filaggrin and tight junction proteins are crucial for IL-13-mediated esophageal barrier dysfunction." American Journal of Physiology-Gastrointestinal and Liver Physiology 315, no. 3 (September 1, 2018): G341—G350. http://dx.doi.org/10.1152/ajpgi.00404.2017.

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Eosinophilic esophagitis (EoE) is an allergy-mediated disease that is accompanied by IL-13 overexpression and an impaired esophageal barrier. Filaggrin (FLG) and tight junction (TJ) proteins are considered to contribute to epithelial barrier function. However, their functional involvement in EoE has not been elucidated. Here, we aimed to determine the IL-13-mediated barrier dysfunction and expression of TJ-related proteins in EoE and to characterize interactions among TJ-related proteins involved in the barrier function of the esophageal epithelium. Biopsy specimens from EoE patients were analyzed. Primary human esophageal epithelial cells (HEECs) were cultured using an air-liquid interface (ALI) system. The permeability of TJs was assayed by biotinylation. Transepithelial electrical resistance (TEER) was measured after stimulation with IL-13 and after siRNA silencing of FLG expression. FLG and TJ genes and proteins were assessed by quantitative RT-PCR, Western blot analysis, and immunofluorescent staining. The biotinylation reagent diffused through the paracellular spaces of whole stratified epithelial layers in EoE biopsy samples. The TEER decreased in ALI-cultured HEECs after IL-13 stimulation. Although the protein level of FLG decreased, that of the TJ proteins increased in the mucosa of EoE biopsy samples and in ALI-cultured HEECs after IL-13 stimulation. IL-13 altered the staining patterns of TJ proteins and the epithelial morphology. FLG siRNA transfection significantly decreased TEER. The IL-13-mediated reduced esophageal barrier is associated with the altered expression pattern but not with the levels of TJ-associated proteins. A deficiency of FLG altered the stratified epithelial barrier. NEW & NOTEWORTHY Esophageal permeability to small molecules was increased in patients with eosinophilic esophagitis (EoE) and could be induced by IL-13 in our unique air-liquid interface-cultured primary multilayer human esophageal epithelial cells in vitro. A deficiency of filaggrin disrupted the esophageal stratified epithelial barrier. The decreased esophageal barrier in EoE was associated with the altered staining pattern of tight junction proteins, although the levels of the proteins themselves do not appear to be changed.

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Islam, Md Shofiqul, and Makoto Ishida. "Interface pn junction arrays with high yielded grown p-Si microneedles by vapor–liquid–solid method at low temperature." Solid-State Electronics 103 (January 2015): 90–97. http://dx.doi.org/10.1016/j.sse.2014.10.009.

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Yarn, K. F. "Experimental Studies of New GaAs Metal/Insulator/p-n+Switches Using Low Temperature Oxide." Active and Passive Electronic Components 25, no. 3 (2002): 233–37. http://dx.doi.org/10.1080/08827510213494.

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First observation of switching behavior is reported in GaAs metal-insulator-p-n+structure, where the thin insulator is grown at low temperature by a liquid phase chemical-enhanced oxide (LPECO) with a thickness of 100 Å. A significant S-shaped negative differential resistance (NDR) is shown to occur that originates from the regenerative feedback in a tunnel metal/insulator/semiconductor (MIS) interface andp-n+junction. The influence of epitaxial doping concentration on the switching and holding voltages is investigated. The switching voltages are found to be decreased when increasing the epitaxial doping concentration, while the holding voltages are almost kept constant. A high turn-off/turn-on resistance ratio up to105has been obtained.

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Mukherjee, Jonaki, Ashok Ranjan, Arvind K. Saxena, Sankar Karan, Dwijesh K. Dutta Majumder, Arnab Ghosh, Sujan Ghosh, Probal K. Das, and Rajat Banerjee. "A novel carbon rich crystalline (C) SiC–Si(n) interface using liquid polycarbosilane as a precursor – a unique Schottky junction." Journal of Materials Chemistry C 1, no. 42 (2013): 6945. http://dx.doi.org/10.1039/c3tc31125b.

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Yalavarthi, Rambabu, Alberto Naldoni, Štěpán Kment, Luca Mascaretti, Hana Kmentová, Ondřej Tomanec, Patrik Schmuki, and Radek Zbořil. "Radiative and Non-Radiative Recombination Pathways in Mixed-Phase TiO2 Nanotubes for PEC Water-Splitting." Catalysts 9, no. 2 (February 23, 2019): 204. http://dx.doi.org/10.3390/catal9020204.

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Anatase and rutile mixed-phase TiO2 with an ideal ratio has been proven to significantly enhance photoelectrochemical (PEC) activity in water-splitting applications due to suppressing the electron–hole recombination. However, the mechanism of this improvement has not been satisfactory described yet. The PEC water oxidation (oxygen evolution) at the interface of TiO2 photoanode and electrolyte solution is determined by the fraction of the photogenerated holes that reach the solution and it is defined as the hole transfer efficiency. The surface and bulk recombination processes in semiconductor photoanodes majorly influence the hole transfer efficiency. In this work, we study the hole transfer process involved in mixed-phase TiO2 nanotube arrays/solution junction using intensity-modulated photocurrent and photovoltage spectroscopy (IMPS and IMVS); then, we correlate the obtained hole transfer rate constants to (photo)electrochemical impedance spectroscopy (PEIS) measurements. The results suggest that the enhanced performance of the TiO2 mixed-phase is due to the improved hole transfer rate across the TiO2/liquid interface as well as to the decrease in the surface trap recombination of the holes.

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Hezinová, Věra, Zeineb Aturki, Karel Klepárník, Giovanni D'Orazio, František Foret, and Salvatore Fanali. "Simultaneous analysis of cocaine and its metabolites in urine by capillary electrophoresis-electrospray mass spectrometry using a pressurized liquid junction nanoflow interface." ELECTROPHORESIS 33, no. 4 (February 2012): 653–60. http://dx.doi.org/10.1002/elps.201100410.

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Lv, Baoqiang, Changming Cheng, Hongyan Yuan, Dan Xiao, and Martin M. F. Choi. "In situ coordination of pyridine, quinoline, and quinoxaline with copper(I) iodide at the solid–liquid interface: Formation, characterization, and function of the microcrystal films." Journal of Materials Research 23, no. 6 (June 2008): 1722–31. http://dx.doi.org/10.1557/jmr.2008.0226.

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An in situ surface-reaction approach has been developed for the synthesis of microcrystals Cu4I4(C6H5N)4, Cu4I4(C9H7N)4, and Cu2I2(C8H6N2) in solid films. Microcrystals of Cu4I4(C6H5N)4, Cu4I4(C9H7N)4, and Cu2I2(C8H6N2) were easily formed on a copper substrate at the solid Cu–liquid pyridine (C6H5N),–quinoline (C9H7N), and–quinoxaline (C8H6N2) interfaces. The resulting microcrystal films were characterized by photoluminescence spectroscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, x-ray diffraction, and electrochemical impedance spectroscopy. The effect of ligands on the morphology of the film materials and their chemical properties were also discussed. These microcrystal films possessing reversible photocurrent and photovoltage properties were studied in detail. The photoactive and mechanically stable complex films described here may provide new strategies for fabricating photoluminescence solid films, photomodulation potential, and current films. The potential applications of the microcrystal films are for small light-induced electronic junction and photoluminescence sensors.

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Lazar, Mihai, Christophe Jacquier, Christiane Dubois, Christophe Raynaud, Gabriel Ferro, Dominique Planson, Pierre Brosselard, Yves Monteil, and Jean-Pierre Chante. "P-Type SiC Layers Formed by VLS Induced Selective Epitaxial Growth." Materials Science Forum 483-485 (May 2005): 633–36. http://dx.doi.org/10.4028/www.scientific.net/msf.483-485.633.

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Al-Si patterns were formed on n-type 4H-SiC substrate by a photolithographic process including wet Al etching and Si/SiC reactive ion etching (RIE) process. RF 1000°C annealing under C3H8 flow was performed to obtain p+ SiC layers by a Vapour-Liquid-Solid (VLS) process. This method enables to grow layers with different width (up to 800 µm) and various shapes. Nevertheless the remaining Al-based droplets on the largest patterns are indicators of crack defects, going through the p+ layer down to the substrate. SIMS analyses have shown an Al profile with high doping concentration near the surface, high N compensation and Si/C stoechiometry variation between the substrate and the VLS layer. The hydrogen profile follows the Al profile in the VLS layer with an overshoot at the VLS/substrate interface. I-V measurements performed directly on the semiconductor layers have confirmed the formed p-n junction and allowed to measure a sheet resistance of 5.5 kW/ı

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Chen, Xin, Tadayuki Oshima, Toshihiko Tomita, Hirokazu Fukui, Jiro Watari, Takayuki Matsumoto, and Hiroto Miwa. "Acidic bile salts modulate the squamous epithelial barrier function by modulating tight junction proteins." American Journal of Physiology-Gastrointestinal and Liver Physiology 301, no. 2 (August 2011): G203—G209. http://dx.doi.org/10.1152/ajpgi.00096.2011.

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Experimental models for esophageal epithelium in vitro either suffer from poor differentiation or complicated culture systems. An air-liquid interface system with normal human bronchial epithelial cells can serve as a model of esophageal-like squamous epithelial cell layers. Here, we explore the influence of bile acids on barrier function and tight junction (TJ) proteins. The cells were treated with taurocholic acid (TCA), glycocholic acid (GCA), or deoxycholic acid (DCA) at different pH values, or with pepsin. Barrier function was measured by transepithelial electrical resistance (TEER) and the diffusion of paracellular tracers (permeability). The expression of TJ proteins, including claudin-1 and claudin-4, was examined by Western blotting of 1% Nonidet P-40-soluble and -insoluble fractions. TCA and GCA dose-dependently decreased TEER and increased paracellular permeability at pH 3 after 1 h. TCA (4 mM) or GCA (4 mM) did not change TEER and permeability at pH 7.4 or pH 4. The combination of TCA and GCA at pH 3 significantly decreased TEER and increased permeability at lower concentrations (2 mM). Pepsin (4 mg/ml, pH 3) did not have any effect on barrier function. DCA significantly decreased the TEER and increased permeability at pH 6, a weakly acidic condition. TCA (4 mM) and GCA (4 mM) significantly decreased the insoluble fractions of claudin-1 and claudin-4 at pH 3. In conclusion, acidic bile salts disrupted the squamous epithelial barrier function partly by modulating the amounts of claudin-1 and claudin-4. These results provide new insights for understanding the role of TJ proteins in esophagitis.

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WANG, MONAN, YUANXIN JI, YUZHENG MA, and JUNTONG JING. "MODELING AND INJURY REPAIR ANALYSIS OF ARTICULAR CARTILAGE BASED ON FIBER CONTENT." Journal of Mechanics in Medicine and Biology 19, no. 08 (December 2019): 1940050. http://dx.doi.org/10.1142/s0219519419400505.

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It has great guiding significance for the prevention of osteoarthritis and the mechanical state of cartilage after tissue engineering repair to study the relationship between the mechanical properties of cartilage and its structure. This paper considered both the consideration of the solid phase, liquid phase, fiber-reinforced phase in the cartilage and the influence of the contents of major fibers and minor fibers near the cartilage surface. Based on these, a tangential zone of cartilage was established, and a certain improvement and optimization of the fiber-reinforced porous elastic model was performed. The Abaqus software and the Fortran language were used to complete simulation. Simulation results were compared with experiment’s results to verify the validity of the model. Finally, the model was used to perform finite element analysis of different degrees of repairable depth under sliding conditions. Several results were obtained. When the indenter is farther from the interface at the repair site, the mechanical changes in the cartilage are relatively stable. The contact stress of the tangential layer repair and the full-layer repair is small. The volume fraction of the liquid phase in the tangential layer and the full layer repair is lower than that in the other layer regions. The liquid flow rate and the Von Mises stress at the junction of the tangential layer repair are very high. Simulation results were used to explore differences in cartilage mechanical properties of different repairable depths, so as to select the best repairable depth for cartilage.

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Chen, Xin, Tadayuki Oshima, Jing Shan, Hirokazu Fukui, Jiro Watari, and Hiroto Miwa. "Bile salts disrupt human esophageal squamous epithelial barrier function by modulating tight junction proteins." American Journal of Physiology-Gastrointestinal and Liver Physiology 303, no. 2 (July 15, 2012): G199—G208. http://dx.doi.org/10.1152/ajpgi.00454.2011.

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Reflux of acid and bile acids contributes to epithelial tissue injury in gastro-esophageal reflux disease. However, the influence of refluxed material on human esophageal stratified epithelial barrier function and tight junction (TJ) proteins has not been fully elucidated. Here, we investigated the influence of acid and bile acids on barrier function and TJ protein distribution using a newly developed air-liquid interface (ALI) in vitro culture model of stratified squamous epithelium based on primary human esophageal epithelial cells (HEECs). Under ALI conditions, HEECs formed distinct epithelial layers on Transwell inserts after 7 days of culture. The epithelial layers formed TJ, and the presence of claudin-1, claudin-4, and occludin were detected by immunofluorescent staining. The NP-40-insoluble fraction of these TJ proteins was significantly higher by day 7 of ALI culture. Exposure of HEECs to pH 2, and taurocholic acid (TCA) and glycocholic acid (GCA) at pH 3, but not pH 4, for 1 h decreased transepithelial electrical resistance (TEER) and increased paracellular permeability. Exposure of cell layers to GCA (pH 3) and TCA (pH 3) for 1 h also markedly reduced the insoluble fractions of claudin-1 and -4. We found that deoxycholic acid (pH 7.4 or 6, 1 h) and pepsin (pH 3, 24 h) significantly decreased TEER and increased permeability. Based on these findings, ALI-cultured HEECs represent a new in vitro model of human esophageal stratified epithelium and are suitable for studying esophageal epithelial barrier functions. Using this model, we demonstrated that acid, bile acids, and pepsin disrupt squamous epithelial barrier function partly by modulating TJ proteins. These results provide new insights into understanding the role of TJ proteins in esophagitis.

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Mansoor, M. M., I. U. Vakarelski, J. O. Marston, T. T. Truscott, and S. T. Thoroddsen. "Stable–streamlined and helical cavities following the impact of Leidenfrost spheres." Journal of Fluid Mechanics 823 (June 23, 2017): 716–54. http://dx.doi.org/10.1017/jfm.2017.337.

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We report results from an experimental study on the formation of stable–streamlined and helical cavity wakes following the free-surface impact of Leidenfrost spheres. Similar to the observations of Mansoor et al. (J. Fluid Mech., vol. 743, 2014, pp. 295–326), we show that acoustic ripples form along the interface of elongated cavities entrained in the presence of wall effects as soon as the primary cavity pinch-off takes place. The crests of these ripples can act as favourable points for closure, producing multiple acoustic pinch-offs, which are found to occur in an acoustic pinch-off cascade. We show that these ripples pacify with time in the absence of physical contact between the sphere and the liquid, leading to extremely smooth cavity wake profiles. More importantly, the downward-facing jet at the apex of the cavity is continually suppressed due to a skin-friction drag effect at the colliding cavity-wall junction, which ultimately produces a stable–streamlined cavity wake. This streamlined configuration is found to experience drag coefficients an order of a magnitude lower than those acting on room-temperature spheres. A striking observation is the formation of helical cavities which occur for impact Reynolds numbers $Re_{0}\gtrsim 1.4\times 10^{5}$ and are characterized by multiple interfacial ridges, stemming from and rotating synchronously about an evident contact line around the sphere equator. The contact line is shown to result from the degeneration of Kelvin–Helmholtz billows into turbulence which are observed forming along the liquid–vapour interface around the bottom hemisphere of the sphere. Using sphere trajectory measurements, we show that this helical cavity wake configuration has 40 %–55 % smaller force coefficients than those obtained in the formation of stable cavity wakes.

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Jensen, Tim, and David L. Saums. "Metallic TIM Testing and Selection for Harsh Environment Applications for GaN RF Semiconductors." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2016, HiTEC (January 1, 2016): 000079–86. http://dx.doi.org/10.4071/2016-hitec-79.

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Summary An important determinant of device reliability is operating temperature control. Maintaining a semiconductor device at or below the maximum rated junction temperature (Tj) is accomplished through careful thermal management design and selection of well-performing thermal interface materials (TIM) that minimize efficiency losses in packaging and between the semiconductor device package and a heat sink or liquid cold plate. Thermal management design is increasingly important in harsh operating environments, especially where higher operating temperatures are specified. Minimizing thermal resistances through each semiconductor package material stack and at the external case or package surface of the device are important aspects of maintaining operating temperatures within specified maximum values. In addition, certain semiconductor devices require an electrical path from the semiconductor case to an external component. Maximizing electrical performance of gallium nitride (GaN) RF semiconductors is critical to system performance, as a primary example. The on-going transition within RF and microwave systems from silicon to GaN devices has increased the need for thermal interface materials which offer both improved thermal performance and electrical conductivity. Additionally, GaN semiconductor die are typically smaller in footprint and, even with equivalent power dissipation values, therefore may operate with higher heat flux values that require greater attention to proper thermal solution design. To address such needs, recently-developed forms of metallic TIM preforms are available for integrated circuits, power semiconductors, and RF devices. Understanding how these materials may be tested and selected for specific application requirements is the subject of this discussion.

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Ramezanpour, Mahnaz, Sophia Moraitis, Jason L. P. Smith, P. J. Wormald, and Sarah Vreugde. "Th17 Cytokines Disrupt the Airway Mucosal Barrier in Chronic Rhinosinusitis." Mediators of Inflammation 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/9798206.

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Cytokine mediated changes in paracellular permeability contribute to a multitude of pathological conditions including chronic rhinosinusitis (CRS). The purpose of this study was to investigate the effect of interferons and of Th1, Th2, and Th17 cytokines on respiratory epithelium barrier function. Cytokines and interferons were applied to the basolateral side of air-liquid interface (ALI) cultures of primary human nasal epithelial cells (HNECs) from CRS with nasal polyp patients. Transepithelial electrical resistance (TEER) and permeability of FITC-conjugated dextrans were measured over time. Additionally, the expression of the tight junction protein Zona Occludens-1 (ZO-1) was examined via immunofluorescence. Data was analysed using ANOVA, followed by Tukey HSD post hoc test. Our results showed that application of interferons and of Th1 or Th2 cytokines did not affect the mucosal barrier function. In contrast, the Th17 cytokines IL-17, IL-22, and IL-26 showed a significant disruption of the epithelial barrier, evidenced by a loss of TEER, increased paracellular permeability of FITC-dextrans, and discontinuous ZO-1 immunolocalisation. These results indicate that Th17 cytokines may contribute to the development of CRSwNP by promoting a leaky mucosal barrier.

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Journal articles on the topic 'Liquid junction interface'

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