| 1. |
- Bai, Qiao, et al.
(author)
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Effect of proinflammatory S100A9 protein on migration and proliferation of microglial cells
- 2023
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In: Journal of Molecular Neuroscience. - : Springer Nature. - 0895-8696 .- 1559-1166. ; 73:11-12, s. 983-995
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Journal article (peer-reviewed)abstract
- Alzheimer’s disease (AD) is a multifactorial disease affecting aging population worldwide. Neuroinflammation became a focus of research as one of the major pathologic processes relating to the disease onset and progression. Proinflammatory S100A9 is the central culprit in the amyloid-neuroinflammatory cascade implicated in AD and other neurodegenerative diseases. We studied the effect of S100A9 on microglial BV-2 cell proliferation and migration. The responses of BV-2 cells to S100A9 stimulation were monitored in real-time using live cell microscopy, transcriptome sequencing, immunofluorescence staining, western blot analysis, and ELISA. We observed that a low dose of S100A9 promotes migration and proliferation of BV-2 cells. However, acute inflammatory condition (i.e., high S100A9 doses) causes diminished cell viability; it is uncovered that S100A9 activates TLR-4 and TLR-7 signaling pathways, leading to TNF-α and IL-6 expression, which affect BV-2 cell migration and proliferation in a concentration-dependent manner. Interestingly, the effects of S100A9 are not only inhibited by TNF-α and IL-6 antibodies. The addition of amyloid-β (Aβ) 1–40 peptide resumes the capacities of BV-2 cells to the level of low S100A9 concentrations. Based on these results, we conclude that in contrast to the beneficial effects of low S100A9 dose, high S100A9 concentration leads to impaired mobility and proliferation of immune cells, reflecting neurotoxicity at acute inflammatory conditions. However, the formation of Aβ plaques may be a natural mechanism that rescues cells from the proinflammatory and cytotoxic effects of S100A9, especially considering that inflammation is one of the primary causes of AD.
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| 2. |
- Hou, Yuanyuan, et al.
(author)
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Comparative study of pressure-induced polymerization of C60 nanorods and single crystals
- 2007
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In: Journal of Physics Condensed Matter. - Bristol : Institute of Physics. - 0953-8984 .- 1361-648X. ; 19:42, s. 425207-
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Journal article (peer-reviewed)abstract
- In this paper, we report a comparative study of pressure-induced polymerization in C60 nanorods and bulk single crystals, treated simultaneously under various pressures and temperatures in the same experiment. For both materials, orthorhombic, tetragonal and rhombohedral phases have been produced under high pressure and high temperature. The structures have been identified and compared between the two sample types by Raman and photoluminescence spectroscopy. There are differences between the Raman and photoluminescence spectra from the two types of materials for all polymeric phases, but especially for the tetragonal phase. From the comparison between nanorods and bulk samples, we tentatively assign photoluminescence peaks for various polymeric phases.
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| 3. |
- Zou, Yonggang, et al.
(author)
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Rotational dynamics of confined C60 from near-infrared Raman studies under high pressure
- 2009
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In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 106:52, s. 22135-22138
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Journal article (peer-reviewed)abstract
- Peapods present a model system for studying the properties of dimensionally constrained crystal structures, whose dynamical properties are very important. We have recently studied the rotational dynamics of C60 molecules confined inside single walled carbon nanotube (SWNT) by analyzing the intermediate frequency mode lattice vibrations using near-infrared Raman spectroscopy. The rotation of C60 was tuned to a known state by applying high pressure, at which condition C60 first forms dimers at low pressure and then forms a single-chain, nonrotating, polymer structure at high pressure. In the latter state the molecules form chains with a 2-fold symmetry. We propose that the C60 molecules in SWNT exhibit an unusual type of ratcheted rotation due to the interaction between C60 and SWNT in the “hexagon orientation,” and the characteristic vibrations of ratcheted rotation becomes more obvious with decreasing temperature.
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| 4. |
- Chen, Hao, et al.
(author)
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Surface-Directed Structural Transition of Amyloidogenic Aggregates and the Resulting Neurotoxicity
- 2020
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In: ACS Omega. - : American Chemical Society (ACS). - 2470-1343. ; 5:6, s. 2856-2864
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Journal article (peer-reviewed)abstract
- The transition of amyloidogenic species into ordered structures (i.e., prefibrillar oligomers, protofibrils, mature fibrils, and amyloidogenic aggregates) is closely associated with many neurodegenerative disease pathologies. It is increasingly appreciated that the liquid-solid interface contributes to peptide aggregation under physiological conditions. However, much remains to be explored on the molecular mechanism of surface-directed amyloid formation. We herein demonstrate that physical environmental conditions (i.e., negatively charged surface) affect amyloid formation. Nontoxic amyloid aggregates quickly develop into intertwisting fibrils on a negatively charged mica surface. These fibrillar structures show significant cytotoxicity on both neuroblastoma cell-lines (SH-SY5Y) and primary neural stem cells. Our results suggest an alternative amyloid development pathway, following which A beta peptides form large amyloidogenic aggregates upon stimulation, and later transit into neurotoxic fibrillar structures while being trapped and aligned by a negatively charged surface. Conceivably, the interplay between chemical and physical environmental conditions plays important roles in the development of neurodegenerative diseases.
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| 5. |
- Huang, Ivy, et al.
(author)
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High performance dual-electrolyte magnesium-iodine batteries that can harmlessly resorb in the environment or in the body
- 2022
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In: Energy & Environmental Science. - : Royal Society of Chemistry (RSC). - 1754-5692 .- 1754-5706. ; 15:10, s. 4095-4108
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Journal article (peer-reviewed)abstract
- Batteries represent the dominant means for storing electrical energy, but many battery chemistries create waste streams that are difficult to manage, and most possess toxic components that limit their use in biomedical applications. Batteries constructed from materials capable of complete, harmless resorption into the environment or into living organisms after a desired period of operation bypass these disadvantages. However, previously reported eco/bioresorbable batteries offer low operating voltages and modest energy densities. Here, we introduce a magnesium-iodine chemistry and dual (ionic liquid/aqueous) electrolyte to overcome these limitations, enabling significant improvements in voltage, areal capacity, areal energy, areal power, volumetric energy, and volumetric power densities over any alternative. Systematic studies reveal key materials and design considerations. Demonstrations of this technology include power supplies for cardiac pacemakers, wireless environmental monitors, and thermal sensors/actuators. These results suggest strong potential for applications where commercial battery alternatives pose risks to the environment or the human body.
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| 6. |
- Huang, Qin, et al.
(author)
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HEWL interacts with dissipated oleic acid micelles, and decreases oleic acid cytotoxicity
- 2019
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In: PLOS ONE. - : PUBLIC LIBRARY SCIENCE. - 1932-6203. ; 14:2
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Journal article (peer-reviewed)abstract
- Senile plaques are well-known hallmarks of Alzheimer's Diseases (AD). However, drugs targeting tangles of the protein tau and plaques of beta-amyloid have no significant effect on disease progression, and the studies on the underlying mechanism of AD remain in high demand. Growing evidence supports the protective role of senile plaques in local inflammation driven by S100A9. We herein demonstrate that oleic acid (OA) micelles interact with hen egg white lysozyme (HEWL) and promote its amyloid formation. Consequently, SH-SY5Y cell line and mouse neural stem cells are rescued from OA toxicity by co-aggregation of OA and HEWL. Using atomic force microscopy in combination with fluorescence microscopy, we revealed that HEWL forms round-shaped aggregates in the presence of OA micelles instead of protofibrils of HEWL alone. These HEWL amyloids act as a sink for toxic OA micelles and their co-aggregate form large clumps, suggesting a protective function in amyloid and OA cytotoxicity.
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| 7. |
- Huang, Weiguo, et al.
(author)
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InAs quantum wells grown on GaP/Si substrate with Ga(In,As)P metamorphic buffers
- 2022
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In: Hongwai Yu Haomibo Xuebao/Journal of Infrared and Millimeter Waves. - 1001-9014. ; 41:1, s. 253-261
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Journal article (peer-reviewed)abstract
- InAs/In0.83Al0.17As quantum wells have been demonstrated on In0.83Al0.17As metamorphic layers on GaP/Si substrates. The effects of GaxIn1-xP and GaAsyP1-y graded buffer layers on the sample performances are investigated. The sample with GaxIn1-xP metamorphic buffer layer has narrower width in X-ray diffraction reciprocal space maps, indicating less misfit dislocations in the sample. Mid-infrared photoluminescence signals have been observed for both samples at room temperature, while the sample with GaxIn1-xP metamorphic buffer shows stronger photoluminescence intensity at all temperatures. The results indicate the metamorphic buffers with mixed cations show superior effects for the mid-infrared InAs quantum wells on GaP/Si composite substrates.
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| 8. |
- Jia, Xueen, et al.
(author)
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Neuroprotective and nootropic drug noopept rescues α-synuclein amyloid cytotoxicity
- 2011
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In: Journal of Molecular Biology. - : Elsevier BV. - 0022-2836 .- 1089-8638. ; 414:5, s. 699-712
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Journal article (peer-reviewed)abstract
- Parkinson's disease is a common neurodegenerative disorder characterized by α-synuclein (α-Syn)-containing Lewy body formation and selective loss of dopaminergic neurons in the substantia nigra. We have demonstrated the modulating effect of noopept, a novel proline-containing dipeptide drug with nootropic and neuroprotective properties, on α-Syn oligomerization and fibrillation by using thioflavin T fluorescence, far-UV CD, and atomic force microscopy techniques. Noopept does not bind to a sterically specific site in the α-Syn molecule as revealed by heteronuclear two-dimensional NMR analysis, but due to hydrophobic interactions with toxic amyloid oligomers, it prompts their rapid sequestration into larger fibrillar amyloid aggregates. Consequently, this process rescues the cytotoxic effect of amyloid oligomers on neuroblastoma SH-SY5Y cells as demonstrated by using cell viability assays and fluorescent staining of apoptotic and necrotic cells and by assessing the level of intracellular oxidative stress. The mitigating effect of noopept against amyloid oligomeric cytotoxicity may offer additional benefits to the already well-established therapeutic functions of this new pharmaceutical.
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| 9. |
- Liu, Claire, et al.
(author)
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Multifunctional Materials Strategies for Enhanced Safety of Wireless, Skin-Interfaced Bioelectronic Devices
- 2023
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In: Advanced Functional Materials. - : Wiley. - 1616-301X .- 1616-3028. ; 33:34
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Journal article (peer-reviewed)abstract
- Many recently developed classes of wireless, skin-interfaced bioelectronic devices rely on conventional thermoset silicone elastomer materials, such as poly(dimethylsiloxane) (PDMS), as soft encapsulating structures around collections of electronic components, radio frequency antennas and, commonly, rechargeable batteries. In optimized layouts and device designs, these materials provide attractive features, most prominently in their gentle, noninvasive interfaces to the skin even at regions of high curvature and large natural deformations. Past studies, however, overlook opportunities for developing variants of these materials for multimodal means to enhance the safety of the devices against failure modes that range from mechanical damage to thermal runaway. This study presents a self-healing PDMS dynamic covalent matrix embedded with chemistries that provide thermochromism, mechanochromism, strain-adaptive stiffening, and thermal insulation, as a collection of attributes relevant to safety. Demonstrations of this materials system and associated encapsulation strategy involve a wireless, skin-interfaced device that captures mechanoacoustic signatures of health status. The concepts introduced here can apply immediately to many other related bioelectronic devices.
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| 10. |
- Shiwei, Tian, et al.
(author)
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Effect of Mo Element on Microstructure and Mechanical Properties of TiAl Alloys
- 2022
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In: Xiyou jinshu cailiao yu gongcheng. - : NORTHWEST INST NONFERROUS METAL RESEARCH. - 1002-185X. ; 51:7, s. 2336-2343
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Journal article (peer-reviewed)abstract
- Four TiAl alloys with different Mo contents were designed, and the microstructure and mechanical properties of these MoTiAl alloys were studied by scanning electron microscope, nanoindentation, and hot compression simulation methods. Results show that with increasing the Mo content, the content of. phase is gradually decreased, while that of beta phase is gradually increased. The Mo element mainly exists in the form of beta phase in the TiAl alloy. During the hot isostatic pressing process, the Mo element is diffused from the. and a 2 phases to the beta phase. The nanoindentation hardness of Mo-TiAl alloy reaches the maximum when the Mo content is 1.59at%, and it is negatively correlated with the interlamellar space. As the content of Mo element increases, the flow stress of Mo-TiAl alloys decreases, and the TiAl alloys with 2.11at% and 3.94at% Mo addtion have poor plasticity due to the Al element segregation.
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