The mixed oxide, Bi2Cu0*1V0*9O5*35 often abbreviated as BiCuVOx, is known as an oxide--ionic conductor. The applicability of this oxide to a potentiometric oxygen sensor was investigated. Oxygen ...concentration cells were fabricated by using a disk of this oxide to test the EMF response to changes in oxygen concentration between 10% and 100% at various temperatures between 300 and 700 deg C. As a result, the performances of the cells were found to depend very much on the kinds of electrode materials. When attached with Pt electrodes, the cell produced the EMF response fairly good only at 600 deg C and above, whereas the oxide--ion transport number was close to unity even at 500 deg C as evaluated from the Faraday efficiency of oxygen pumping current. The use of a perovskite--type oxide (La0*6Sr0*4Co0*8Fe0*2O3) instead of Pt was found to enable the cell to work at 400 deg C and above. Especially excellent performances were observed when the oxide was mixed with BiCuVOx powder prior to being applied on the BiCuVOx disk as the electrodes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Non‐neural extracellular matrix (ECM) has limited application in humanized physiological neural modeling due to insufficient brain‐specificity and safety concerns. Although brain‐derived ECM contains ...enriched neural components, certain essential components are partially lost during the decellularization process, necessitating augmentation. Here, it is demonstrated that the laminin‐augmented porcine brain‐decellularized ECM (P‐BdECM) is xenogeneic factor‐depleted as well as favorable for the regulation of human neurons, astrocytes, and microglia. P‐BdECM composition is comparable to human BdECM regarding brain‐specificity through the matrisome and gene ontology‐biological process analysis. As augmenting strategy, laminin 111 supplement promotes neural function by synergic effect with laminin 521 in P‐BdECM. Annexin A1(ANXA1) and Peroxiredoxin(PRDX) in P‐BdECM stabilized microglial and astrocytic behavior under normal while promoting active neuroinflammation in response to neuropathological factors. Further, supplementation of the brain‐specific molecule to non‐neural matrix also ameliorated glial cell inflammation as in P‐BdECM. In conclusion, P‐BdECM‐augmentation strategy can be used to recapitulate humanized pathophysiological cerebral environments for neurological study.
Porcine‐derived brain decellularized extracellular matrix (P‐BdECM) augmented with LN111 is developed to construct physiological human brain model. The similarity of P‐BdECM is specifically validated to human BdECM and brain‐specific proteins in ameliorating neural differentiation and neuroinflammation. The augmented P‐BdECM is favorable to recapitulate the neural microenvironment for the study of cellular behavior and the role of ECM in neural processes.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Drug-induced skin sensitization is prevalent worldwide and can trigger life-threatening health conditions, such as Stevens Johnson Syndrome. However, existing in vitro skin models cannot adequately ...predict the skin sensitization effects of drugs administered into the systemic circulation because dermal inflammation and injury are preceded by conversion of parent drugs into antigenic reactive metabolites in the liver and subsequent activation of the immune system. Here, we demonstrate that recapitulation of these early tandem cellular processes in a compartmentalized liver-immune coculture array is sufficient to predict the skin sensitization potential of systemic drugs. Human progenitor cell (HepaRG)-derived hepatocyte spheroids and U937 myeloid cells, a representative antigen presenting cell (APC), can maintain their respective functions in 2 concentric micro-chambers, which are connected by a diffusion microchannel network. Paradigm drugs that are reported to cause severe cutaneous drug reactions (i.e. carbamazepine, phenytoin and allopurinol) can be metabolized into their reactive metabolites, which diffuse efficiently into the adjoining immune compartment within a 48 hour period. By measuring the extent of U937 activation as indicated by IL8, IL1β and CD86 upregulation upon drug administration, we show that the liver-immune coculture array more consistently and reliably distinguish all 3-paradigm skin sensitizing drugs from a non-skin sensitizer than conventional bulk Transwell coculture. Given its miniaturized format, design simplicity and prediction capability, this novel in vitro system can be readily scaled into a screenable platform to identify the skin sensitization potential of systemically-administered drugs.
Cell-adhesive particles are of significant interest in biotechnology, the bioengineering of complex tissues, and biomedical research. Their applications range from platforms to increase the ...efficiency of anchorage-dependent cell culture to building blocks to loading cells in heterogeneous structures to clonal-population growth monitoring to cell sorting. Although useful, currently available cell-adhesive particles can accommodate only homogeneous cell culture. Here, we report the design of anisotropic hydrogel microparticles with tunable cell-adhesive regions as first step toward micropatterned cell cultures on particles. We employed stop flow lithography (SFL), the coupling reaction between amine and N-hydroxysuccinimide (NHS) and streptavidin–biotin chemistry to adjust the localization of conjugated collagen and poly-l-lysine on the surface of microscale particles. Using the new particles, we demonstrate the attachment and formation of tight junctions between brain endothelial cells. We also demonstrate the geometric patterning of breast cancer cells on particles with heterogeneous collagen coatings. This new approach avoids the exposure of cells to potentially toxic photoinitiators and ultraviolet light and decouples in time the microparticle synthesis and the cell culture steps to take advantage of the most recent advances in cell patterning available for traditional culture substrates.
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IJS, KILJ, NUK, PNG, UL, UM
Abstract Immune responses in the brain are thought to play a role in disorders of the central nervous system, but an understanding of the process underlying how immune cells get into the brain and ...their fate there remains unclear. In this study, we used a 2-photon microscopy to reveal that neutrophils infiltrate brain and migrate toward amyloid plaques in a mouse model of Alzheimer's disease. These findings suggest a new molecular process underlying the pathophysiology of Alzheimer's disease.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
How the capillary burst microvalve works Cho, Hansang; Kim, Ho-Young; Kang, Ji Yoon ...
Journal of colloid and interface science,
02/2007, Volume:
306, Issue:
2
Journal Article
Peer reviewed
The capillary burst microvalve offers an attractive means to regulate microliquid flow owing to its simple structure and operation process. However, there existed no rigorous theoretical work to ...elucidate how the valve works and consequently to predict the valve-bursting condition. Therefore, here we report the theoretical investigation of how the capillary burst valve can stop the advancing liquid meniscus and when it bursts. We confirm our theory with experiments using a centrifugal microfluidic valve system fabricated by soft lithography.
We provide a theoretical framework to explain how the capillary burst valve, as shown in this figure, works.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Interfering with the assembly of Amyloid β (Aβ) peptides from monomer to oligomeric species and fibrils or promoting their clearance from the brain are targets of anti-Aβ-directed therapies in ...Alzheimer disease. Here we demonstrate that cromolyn sodium (disodium cromoglycate), a Food and Drug Administration-approved drug already in use for the treatment of asthma, efficiently inhibits the aggregation of Aβ monomers into higher-order oligomers and fibrils in vitro without affecting Aβ production. In vivo, the levels of soluble Aβ are decreased by over 50% after only 1 week of daily intraperitoneally administered cromolyn sodium. Additional in vivo microdialysis studies also show that this compound decreases the half-life of soluble Aβ in the brain. These data suggest a clear effect of a peripherally administered, Food and Drug Administration-approved medication on Aβ economy, supporting further investigation of the potential long-term efficacy of cromolyn sodium in Alzheimer disease.Cromolyn sodium is an FDA-approved drug structurally similar to fisetin, an antiamyloidogenic molecule.
Cromolyn sodium interferes with amyloid β (Aβ) aggregation in vitro while rapidly decreasing the levels of soluble Aβ peptides in vivo after a week.
Cromolyn sodium may have an impact on amyloid economy.
Developing new disease-modifying therapeutics remains an urgent need in the treatment of Alzheimer disease.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Drug-induced skin sensitization is prevalent worldwide and can trigger life-threatening health conditions, such as Stevens Johnson Syndrome. However, existing
in vitro
skin models cannot adequately ...predict the skin sensitization effects of drugs administered into the systemic circulation because dermal inflammation and injury are preceded by conversion of parent drugs into antigenic reactive metabolites in the liver and subsequent activation of the immune system. Here, we demonstrate that recapitulation of these early tandem cellular processes in a compartmentalized liver-immune coculture array is sufficient to predict the skin sensitization potential of systemic drugs. Human progenitor cell (HepaRG)-derived hepatocyte spheroids and U937 myeloid cells, a representative antigen presenting cell (APC), can maintain their respective functions in 2 concentric micro-chambers, which are connected by a diffusion microchannel network. Paradigm drugs that are reported to cause severe cutaneous drug reactions (
i.e.
carbamazepine, phenytoin and allopurinol) can be metabolized into their reactive metabolites, which diffuse efficiently into the adjoining immune compartment within a 48 hour period. By measuring the extent of U937 activation as indicated by IL8, IL1β and CD86 upregulation upon drug administration, we show that the liver-immune coculture array more consistently and reliably distinguish all 3-paradigm skin sensitizing drugs from a non-skin sensitizer than conventional bulk Transwell coculture. Given its miniaturized format, design simplicity and prediction capability, this novel
in vitro
system can be readily scaled into a screenable platform to identify the skin sensitization potential of systemically-administered drugs.
Recapitulation of liver-immune interactions in a microfluidic compartmentalized coculture array is sufficient to accurately predict systemic drug-induced skin sensitization.
Extracting and exploiting edge information is important for various computer vision tasks. According to the physical characteristics, edges are further categorized into reflectance, illumination, ...normal, and depth discontinuities. Previous studies for edge discontinuity classification have achieved impressive performance in extracting discontinuities, but the capacity of classification remains limited. This paper proposes TriDecTr, a novel network comprising a transformer-based encoder to improve semantic understanding and a tri-directional decoder to explore relationships among categories. Extensive experiments demonstrate that TriDecTr achieves state-of-the-art performance on the BSDS-RIND dataset with 0.531 in ODS, 0.571 in OIS, and 0.461 in AP. Moreover, TriDecTr significantly narrows the performance gap between illumination edges and the other categories from 0.191 to 0.118 in ODS.
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