Ischemic stroke, which accounts for 75-80% of all strokes, is the predominant cause of morbidity and mortality worldwide. The post-stroke immune response has recently emerged as a new breakthrough ...target in the treatment strategy for ischemic stroke. Glial cells, including microglia, astrocytes, and oligodendrocytes, are the primary components of the peri-infarct environment in the central nervous system (CNS) and have been implicated in post-stroke immune regulation. However, increasing evidence suggests that glial cells exert beneficial and detrimental effects during ischemic stroke. Microglia, which survey CNS homeostasis and regulate innate immune responses, are rapidly activated after ischemic stroke. Activated microglia release inflammatory cytokines that induce neuronal tissue injury. By contrast, anti-inflammatory cytokines and neurotrophic factors secreted by alternatively activated microglia are beneficial for recovery after ischemic stroke. Astrocyte activation and reactive gliosis in ischemic stroke contribute to limiting brain injury and re-establishing CNS homeostasis. However, glial scarring hinders neuronal reconnection and extension. Neuroinflammation affects the demyelination and remyelination of oligodendrocytes. Myelin-associated antigens released from oligodendrocytes activate peripheral T cells, thereby resulting in the autoimmune response. Oligodendrocyte precursor cells, which can differentiate into oligodendrocytes, follow an ischemic stroke and may result in functional recovery. Herein, we discuss the mechanisms of post-stroke immune regulation mediated by glial cells and the interaction between glial cells and neurons. In addition, we describe the potential roles of various glial cells at different stages of ischemic stroke and discuss future intervention targets.
The injured spinal cord is difficult to repair and regenerate. Traditional treatments are not effective. Stem cells are a type of cells that have the potential to differentiate into various cells, ...including neurons. They exert a therapeutic effect by safely and effectively differentiating into neurons or replacing damaged cells, secreting neurotrophic factors, and inhibiting the inflammatory response. Many types of stem cells have been used for transplantation, and each has its own advantages and disadvantages. This review discusses the possible mechanisms of stem cell therapy for spinal cord injury, and the types of stem cells commonly used in experiments, to provide a reference for basic and clinical research on stem cell therapy for spinal cord injury.
Neuroinflammation and oxidative stress play important roles in early brain injury following subarachnoid hemorrhage (SAH). This study is the first to show that activation of apelin receptor (APJ) by ...apelin-13 could reduce endoplasmic reticulum (ER)-stress-associated inflammation and oxidative stress after SAH.
Apelin-13, apelin siRNA, APJ siRNA, and adenosine monophosphate-activated protein kinase (AMPK) inhibitor-dorsomorphin were used to investigate if the activation of APJ could provide neuroprotective effects after SAH. Brain water content, neurological functions, blood-brain barrier (BBB) integrity, and inflammatory molecules were evaluated at 24 h after SAH. Western blotting and immunofluorescence staining were applied to assess the expression of target proteins.
The results showed that endogenous apelin, APJ, and p-AMPK levels were significantly increased and peaked in the brain 24 h after SAH. In addition, administration of exogenous apelin-13 significantly alleviated neurological functions, attenuated brain edema, preserved BBB integrity, and also improved long-term spatial learning and memory abilities after SAH. The underlying mechanism of the neuroprotective effects of apelin-13 is that it suppresses microglia activation, prevents ER stress from overactivation, and reduces the levels of thioredoxin-interacting protein (TXNIP), NOD-like receptor pyrin domain-containing 3 protein (NLRP3), Bip, cleaved caspase-1, IL-1β, TNFα, myeloperoxidase (MPO), and reactive oxygen species (ROS). Furthermore, the use of APJ siRNA and dorsomorphin abolished the neuroprotective effects of apelin-13 on neuroinflammation and oxidative stress.
Exogenous apelin-13 binding to APJ attenuates early brain injury by reducing ER stress-mediated oxidative stress and neuroinflammation, which is at least partly mediated by the AMPK/TXNIP/NLRP3 signaling pathway.
Nanotechnology has been extensively studied and exploited for cancer treatment as nanoparticles can play a significant role as a drug delivery system. Compared to conventional drugs, ...nanoparticle-based drug delivery has specific advantages, such as improved stability and biocompatibility, enhanced permeability and retention effect, and precise targeting. The application and development of hybrid nanoparticles, which incorporates the combined properties of different nanoparticles, has led this type of drug-carrier system to the next level. In addition, nanoparticle-based drug delivery systems have been shown to play a role in overcoming cancer-related drug resistance. The mechanisms of cancer drug resistance include overexpression of drug efflux transporters, defective apoptotic pathways, and hypoxic environment. Nanoparticles targeting these mechanisms can lead to an improvement in the reversal of multidrug resistance. Furthermore, as more tumor drug resistance mechanisms are revealed, nanoparticles are increasingly being developed to target these mechanisms. Moreover, scientists have recently started to investigate the role of nanoparticles in immunotherapy, which plays a more important role in cancer treatment. In this review, we discuss the roles of nanoparticles and hybrid nanoparticles for drug delivery in chemotherapy, targeted therapy, and immunotherapy and describe the targeting mechanism of nanoparticle-based drug delivery as well as its function on reversing drug resistance.
Hydrocephalus (HCP) is a common complication in patients with subarachnoid hemorrhage. In this review, we summarize the advanced research on HCP and discuss the understanding of the molecular ...originators of HCP and the development of diagnoses and remedies of HCP after SAH. It has been reported that inflammation, apoptosis, autophagy, and oxidative stress are the important causes of HCP, and well-known molecules including transforming growth factor, matrix metalloproteinases, and iron terminally lead to fibrosis and blockage of HCP. Potential medicines for HCP are still in preclinical status, and surgery is the most prevalent and efficient therapy, despite respective risks of different surgical methods, including lamina terminalis fenestration, ventricle-peritoneal shunting, and lumbar-peritoneal shunting. HCP remains an ailment that cannot be ignored and even with various solutions the medical community is still trying to understand and settle why and how it develops and accordingly improve the prognosis of these patients with HCP.
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•Three-dimensional amorphous SiO2@GA ultralight composite was prepared via a one-pot route.•SiO2@GA exhibited high surface area, large pore volume, and narrow meso-macoporous size ...distribution.•SiO2@GA electrode exhibited high specific capacity and stable cycling performance.•SiO2@GA electrode displayed excellent rate-capability.
A three-dimensional amorphous SiO2@graphene aerogel (SiO2@GA) composites as anode material for lithium ion batteries was successfully synthesized via a one-pot process. The materials were characterized by nitrogen adsorption-desorption, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectra and Fourier-Transform infrared spectra. The results demonstrate that the SiO2@GA composites are in meso-macoporous structures and present large surface area (SBET=396.9m2g−1) and high pore volume (Vp=0.67cm3g−1). Meanwhile, the incorporation of SiO2 does not make obvious effect at the reduction degree of GO to assemble GA. The results of their electrochemical performance reveal that in contrast with bare SiO2, the SiO2@GA anode exhibit higher reversible capacity (∼300mAhg−1 at a current density of 500mAg−1), more stable cycling performance, and excellent rate-capability. The significantly improves electrochemical performance may be ascribed to the 3D aerogel structure and the doping of GA.
An energy-based identification method is proposed to investigate the seismic failure mechanism of landslides with discontinuities. The proposed method was verified by using shaking table tests on a ...rock slope with discontinuous structural planes. The results show that it is feasible to analyze the seismic failure mechanism of the slope by using Hilbert-Huang transform (HHT) and marginal spectrum based on seismic Hilbert energy. Earthquake energy mainly concentrating in the low-frequency components (15–17 Hz) and high-frequency components (20–40 Hz), in Hilbert energy spectrum and the marginal spectrum, respectively, suggests that they can identify the overall and local dynamic response of the slope, respectively, in combination with the Fourier spectrum analysis. In addition, the analyses of marginal spectrum can better clarify the slope dynamic damage process from the energy-based perspective, including no seismic damage stage, local damage stage, and sliding failure stage. The difference of seismic Hilbert energy between slip mass and sliding body causes their different seismic responses. The seismic failure mechanism of the landslide is identified from the energy-based perspective: the seismic Hilbert energy in 20–40 Hz mainly induces the local damage of the slope above the topmost bedding structural plane, and local failure develops first at the platform, under 0.297 g; the surface slope gradually forms a sliding body with the accumulation of local damage, and the seismic Hilbert energy in 15–17 Hz further promotes the landslide subject to 0.446 g.
Traumatic brain injury (TBI) is one of the most common diseases in the central nervous system (CNS) with high mortality and morbidity. Patients with TBI usually suffer many sequelae in the life time ...post injury, including neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). However, the pathological mechanisms connecting these two processes have not yet been fully elucidated. It is important to further investigate the pathophysiological mechanisms underlying TBI and TBI-induced neurodegeneration, which will promote the development of precise treatment target for these notorious neurodegenerative consequences after TBI. A growing body of evidence shows that neuroinflammation is a pivotal pathological process underlying chronic neurodegeneration following TBI. Microglia, as the immune cells in the CNS, play crucial roles in neuroinflammation and many other CNS diseases. Of interest, microglial activation and functional alteration has been proposed as key mediators in the evolution of chronic neurodegenerative pathology following TBI. Here, we review the updated studies involving phenotypical and functional alterations of microglia in neurodegeneration after injury, survey key molecules regulating the activities and functional responses of microglia in TBI pathology, and explore their potential implications to chronic neurodegeneration after injury. The work will give us a comprehensive understanding of mechanisms driving TBI-related neurodegeneration and offer novel ideas of developing corresponding prevention and treatment strategies for this disease.
The construction of anode materials for sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs) with a high energy and a long lifespan is significant and still challenging. Here, ...sulfur-defective vanadium sulfide/carbon fiber composites (D-V5S8/CNFs) are designed and fabricated by a facile electrospinning method, followed by sulfuration treatment. The unique architecture, in which V5S8 nanoparticles are confined inside the carbon fiber, provides a short-range channel and abundant adsorption sites for ion storage. Moreover, enlarged interlayer spacings could also alleviate the volume changes, and offer small vdW interactions and ionic diffusion resistance to store more Na and K ions reversibly and simultaneously. The DFT calculations further demonstrate that sulfur defects can effectively facilitate the adsorption behavior of Na+ and K+ and offer low energy barriers for ion intercalation. Taking advantage of the functional integration of these merits, the D-V5S8/CNF anode exhibits excellent storage performance and long-term cycling stability. It reveals a high capacity of 462 mA h g−1 at a current density of 0.2 A g−1 in SIBs, while it is 350 mA h g−1 at 0.1 A g−1 in PIBs, as well as admirable long-term cycling characteristics (190 mA h g−1/17 000 cycles/5 A g−1 for SIBs and 165 mA h g−1/3000 cycles/1 A g−1 for PIBs). Practically, full SIBs upon pairing with a Na3V2(PO4)3 cathode also exhibit superior performance.
The F-Co-MOF/rGO hybrid with hollow urchins nanostructure has been developed to improve kinetics and mechanical stability for high power LIBs with superior rate capacity retention and long cycling ...stability.
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To obtain MOFs materials with good electrochemical performance in both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), a kind of hollow urchins Co-MOF with doping fluorine (F) was in-situ assembled on reduced graphene oxide (rGO) using a simple solvothermal reaction. According to XRD, XPS and EDS mapping analysis, the molecular structure should be Co2Fx(OH)1-x2(C8O4H4) (denoted as F-Co-MOF). When the composite material is used as active material to assemble LIBs, it not only presents the outstanding reversible capacity (1202.0 mA h g−1 at 0.1 A g−1), but also gives the excellent rate performance and cycle performance (771.5 mA h g−1 at 2 A g−1 after 550 repeated cycles). The remarkable lithium storage capacity of F-Co-MOF/rGO is also reflected in the full cell, where it can still maintain a high capacity of 165.2 mA h g−1 after 300 cycles at 0.2 A g−1. It benefits from the synergistic effect of F-Co-MOF and high conductive rGO networks, so that the reversibility of lithium and sodium storage can be improved. This kind of F doped solvothermal synthesis of MOFs is of great significance for the exploration of high performance materials.
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