34 research outputs found

    Resveratrol Promotes Diabetic Wound Healing via SIRT1-FOXO1-c-Myc Signaling Pathway-Mediated Angiogenesis

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    Background/Aims: Diabetic non-healing skin ulcers represent a serious challenge in clinical practice, in which the hyperglycemia-induced disturbance of angiogenesis, and endothelial dysfunction play a crucial role. Resveratrol (RES), a silent information regulator 1 (SIRT1) agonist, can improve endothelial function and has strong pro-angiogenic properties, and has thus become a research focus for the treatment of diabetic non-healing skin ulcers; however, the underlying mechanism by which RES regulates these processes remains unclear. Therefore, the present study was intended to determine if RES exerts its observed protective role in diabetic wound healing by alleviating hyperglycemia-induced endothelial dysfunction and the disturbance of angiogenesis.Methods: We investigated the effects of RES on cell migration, cell proliferation, apoptosis, tube formation, and the underlying molecular mechanisms in 33 mM high glucose-stimulated human umbilical vein endothelial cells (HUVECs) by semi-quantitative RT-PCR, western blot analysis, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, and immunofluorescence in vitro. We further explored the role of RES on endothelial dysfunction and wound healing disturbance in db/db mice by TUNEL staining, immunofluorescence, and photography in vivo.Results: We observed an obvious inhibition of hyperglycemia-triggered endothelial dysfunction and a disturbance of angiogenesis, followed by the promotion of diabetic wound healing via RES, along with restoration of the activity of the hyperglycemia-impaired SIRT1 signaling pathway. Pretreatment with EX-527, a SIRT1 inhibitor, abolished the RES-mediated endothelial protection and pro-angiogenesis action, and then delayed diabetic wound healing. Furthermore, examination of the overexpression of forkhead box O1 (FOXO1), a transcription factor substrate of SIRT1, in HUVECs and db/db mice revealed that RES activated SIRT1 to restore hyperglycemia-triggered endothelial dysfunction and disturbance of angiogenesis, followed by the promotion of diabetic wound healing in a c-Myc-dependent manner. Pretreatment with 10058-F4, a c-Myc inhibitor, repressed RES-mediated endothelial protection, angiogenesis, and diabetic wound healing.Conclusion: Our findings indicate that the positive role of RES in diabetic wound healing via its SIRT1-dependent endothelial protection and pro-angiogenic effects involves the inhibition of FOXO1 and the de-repression of c-Myc expression

    Additively manufactured metallic biomaterials

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    Metal additive manufacturing (AM) has led to an evolution in the design and fabrication of hard tissue substitutes, enabling personalized implants to address each patient's specific needs. In addition, internal pore architectures integrated within additively manufactured scaffolds, have provided an opportunity to further develop and engineer functional implants for better tissue integration, and long-term durability. In this review, the latest advances in different aspects of the design and manufacturing of additively manufactured metallic biomaterials are highlighted. After introducing metal AM processes, biocompatible metals adapted for integration with AM machines are presented. Then, we elaborate on the tools and approaches undertaken for the design of porous scaffold with engineered internal architecture including, topology optimization techniques, as well as unit cell patterns based on lattice networks, and triply periodic minimal surface. Here, the new possibilities brought by the functionally gradient porous structures to meet the conflicting scaffold design requirements are thoroughly discussed. Subsequently, the design constraints and physical characteristics of the additively manufactured constructs are reviewed in terms of input parameters such as design features and AM processing parameters. We assess the proposed applications of additively manufactured implants for regeneration of different tissue types and the efforts made towards their clinical translation. Finally, we conclude the review with the emerging directions and perspectives for further development of AM in the medical industry.National Institutes of Health || The Natural Sciences and Engineering Research Council of Canada || Network for Holistic Innovation in Additive Manufacturin

    Air-Stable Metal Nanowire Networks for Transparent Flexible Electrodes

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    Transparent conductive electrodes are essential components in many optoelectronic devices such as solar cells, touch panels, and organic light-emitting diodes (OLEDs), all of which are growing in demand. Traditionally, this role has been well served by doped metal oxides, the most common of which is indium tin oxide, or ITO, which alone accounts for 93% of the entire market of the transparent conductor. However, there are several attributes of ITO that are undesirable. (1), ITO is a ceramic material that is brittle and prone to cracking. (2), The abundance of indium in the earth’s crust is low (0.05 ppm), and its cost is correspondingly high, approximately 700kg−1.(3),ITOisproducedbyaslowvaporphasesputteringprocess,leadingtohighfabricationcostthatdominatesthecostofITO(Indiumcostsonly 2700 kg-1. (3), ITO is produced by a slow vapor phase sputtering process, leading to high fabrication cost that dominates the cost of ITO (Indium costs only ~2% for 100 nm thick ITO). In addition, the rate of film throughput decreases with increasing film thickness, making thicker, high-conductivity ITO (~26/m2 for 10 Ω sq-1) more expensive than thinner, low-conductivity ITO (~5.5/m2for150Ωsq−1),whichisespeciallyproblematicforOLEDsandsolarcellsduetotheirneedtocarryhighercurrents,andthususerelativelyexpensiveITOwithalowsheetresistance.Inthesedevices,ITOcanaccountforover505.5/m2 for 150 Ω sq-1), which is especially problematic for OLEDs and solar cells due to their need to carry higher currents, and thus use relatively expensive ITO with a low sheet resistance. In these devices, ITO can account for over 50% of the material cost.This proposal will focus on developing scalable and cost-efficient methods to fabricate air-stable metal nanowire networks for transparent flexible electronics, targeting at a sheet resistance (Rs) of <10Ωsq-1 at 90% transmittance (T) and low cost at <5/m2. This overall objective will be realized through two thrusts: (1), developing air-stable, highly-oriented epitaxial Ag@Au core-shell nanowire networks, aiming for large-scale roll-to-roll solution-phase fabrication of high-performance transparent conducting films for flexible optoelectronics; (2), developing air-stable super-stretchable Cu@rGO core-shell nanowire networks, aiming at cost-efficient foldable and wearable electronics

    Research of ddi based on multi-label conditional random field

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    The detection of drug name and drug-drug interaction(DDI) is considered as a sequence labeling task in this paper. We present the multi-label CRF method to complete it. Compared to the traditional method, our method can not only identify drug names, but also can identify drug-drug interaction. According to the characteristics of medical texts, this paper extracts the good features of the description of DDI. The proposed method has good performance in DDIExtraction 2013 evaluation corpus

    Research of ddi based on multi-label conditional random field

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    The detection of drug name and drug-drug interaction(DDI) is considered as a sequence labeling task in this paper. We present the multi-label CRF method to complete it. Compared to the traditional method, our method can not only identify drug names, but also can identify drug-drug interaction. According to the characteristics of medical texts, this paper extracts the good features of the description of DDI. The proposed method has good performance in DDIExtraction 2013 evaluation corpus

    Microfluidics and Organ-on-a-Chip for Disease Modeling and Drug Screening

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    The convergence of microfluidics and organ-on-a-chip (OoC) technologies has revolutionized our ability to create advanced in vitro models that recapitulate complex physiological processes [...

    The Development and Adoption of Online Learning in Pre- and Post-COVID-19: Combination of Technological System Evolution Theory and Unified Theory of Acceptance and Use of Technology

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    After the outbreak of COVID-19, schools heavily depend on e-learning technologies and tools to shift from in-person class to online. This review article analyzes the changes of technology evolution and technology adoption of e-learning in pre- and post-COVID-19 based on the Technology System Evaluation Theory (TSET) and technology adoption of e-learning based on the Unified Theory of Acceptance and Use of Technology (UTAUT). We intend to explore the interaction of technology evolution and technology adoption in the different focus of e-learning technology in the two stages and the particularity and heterogeneity of the UTAUT model. The results indicate that (1) The moderating results of technology evolution are proposed and evaluated under the UTAUT model before the COVID-19 outbreak. Studies after the COVID-19 pandemic paid more attention to technology efficiency rather than effectiveness; (2) Research on e-learning focuses on the infrastructure to reach more users after the outbreak of COVID-19 because e-learning is the only way to continue education; (3) COVID-19 fear moderates the relationship between the external factors and the behavior intention of e-learning users. The lack of financial support on technology evolution will directly weaken the implementation of new technology. Social Isolation offers more opportunities for students to engage in e-learning. Meanwhile, it slows down the implementation of e-learning because of out-to-date hardware and software. This article offers an enhanced understanding of the interaction of technology evolution and technology adoption under unexpected environments and provides practical insights into how to promote new technology in a way that users will accept and use easily. This study can be tested and extended by empirical research in the future

    Screen-Printed Textile-Based Electrochemical Biosensor for Noninvasive Monitoring of Glucose in Sweat

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    Wearable sweat biosensors for noninvasive monitoring of health parameters have attracted significant attention. Having these biosensors embedded in textile substrates can provide a convenient experience due to their soft and flexible nature that conforms to the skin, creating good contact for long-term use. These biosensors can be easily integrated with everyday clothing by using textile fabrication processes to enhance affordable and scalable manufacturing. Herein, a flexible electrochemical glucose sensor that can be screen-printed onto a textile substrate has been demonstrated. The screen-printed textile-based glucose biosensor achieved a linear response in the range of 20–1000 µM of glucose concentration and high sensitivity (18.41 µA mM−1 cm−2, R2 = 0.996). In addition, the biosensors show high selectivity toward glucose among other interfering analytes and excellent stability over 30 days of storage. The developed textile-based biosensor can serve as a platform for monitoring bio analytes in sweat, and it is expected to impact the next generation of wearable devices.Applied Science, Faculty ofNon UBCElectrical and Computer Engineering, Department ofMaterials Engineering, Department ofReviewedFacultyResearche
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