Reactive astrocytes can be transformed into new neurons. Vascular endothelial growth factor (VEGF) promotes the transformation of reactive astrocytes into neurons in ischemic brain. Therefore, in ...this study, the molecular mechanism of VEGF's effect on ischemia/hypoxia‐induced astrocyte to neuron transformation was investigated in the models of rat middle cerebral artery occlusion (MCAO) and in astrocyte culture with oxygen and glucose deprivation (OGD). We found that VEGF enhanced ischemia‐induced Pax6, a neurogenic fate determinant, expression and Erk phosphorylation in reactive astrocytes and reduced infarct volume of rat brain at 3 days after MCAO, which effects could be blocked by administration of U0126, a MAPK/Erk inhibitor. In cultured astrocytes, VEGF also enhanced OGD‐induced Erk phosphorylation and Pax6 expression, which was blocked by U0126, but not wortmannin, a PI3K/Akt inhibitor, or SB203580, a MAPK/p38 inhibitor, suggesting VEGF enhanced Pax6 expression via activation of MAPK/Erk pathway. OGD induced the increase of miR365 and VEGF inhibited the increase of OGD‐induced miR365 expression. However, miR365 agonists blocked VEGF‐enhanced Pax6 expression in hypoxic astrocytes, but did not block VEGF‐enhanced Erk phosphorylation. We further found that VEGF promoted OGD‐induced astrocyte‐converted to neuron. Interestingly, both U0126 and Pax6 RNAi significantly reduced enhancement of VEGF on astrocytes‐to‐neurons transformation, as indicated Dcx and MAP2 immunopositive signals in reactive astrocytes. Moreover, those transformed neurons become mature and functional. We concluded that VEGF enhanced astrocytic neurogenesis via the MAPK/Erk‐miR‐365‐Pax6 signal axis. The results also indicated that astrocytes play important roles in the reconstruction of neurovascular units in brain after stroke.
Main points
In hypoxia‐damaged astrocytes, VEGF activates the MAPK/Erk pathway and inhibits miR‐365, which upregulates Pax6 protein expressions via VEGFR2.
The MAPK/Erk‐miR‐365‐Pax6 signaling axis played a role in VEGF‐mediated astrocyte trans6 differentiation into mature neurons in hypoxic reactive astrocytes.
Reactive astrocytes play important roles in reconstruction of neurovascular units.
In the electronics industry environment, rapid recognition of objects to be grasped from digital images is essential for visual guidance of intelligent robots. However, electronic components have a ...small size, are difficult to distinguish, and are in motion on a conveyor belt, making target detection more difficult. For this reason, the YOLOv4-tiny method is used to detect electronic components and is improved. Then, different network structures are built for the adaptive integration of middle- and high-level features to address the phenomenon in which the original algorithm integrates all feature information indiscriminately. The method is deployed on an electronic component dataset for validation. Experimental results show that the accuracy of the original algorithm is improved from 93.74 to 98.6%. Compared with other current mainstream algorithms, such as Faster RCNN, SSD, RefineDet, EfficientDet, and YOLOv4, the method can maintain high detection accuracy at the fastest speed. The method can provide a technical reference for the development of manufacturing robots in the electronics industry.
Fire safety and prevention of combustible materials are of paramount importance in modern society but have been a global challenge. Frequent fire disasters cause massive casualties and irreparable ...property losses and negatively impact the global environment. A recent increasing concern is to develop smart fire warning materials and sensors that combine traditional passive flame retardant strategies and active fire alarm response. However, there still lacks an incisive and comparative overview of such fire warning systems. This review comprehensively discusses passive flame retardant materials, traditional active fire warning sensors, and next-generation smart fire warning materials and sensors, in addition to the flammability of combustible materials. The conceptual design, synthesis, characterizations, and fabrication strategies of smart warning materials are systematically reviewed. Subsequently, the performance and applications of different fire warning sensor systems, including resistance-type, phase/shape change, thermoelectric responsive and colour-change observation, were reviewed and compared to understand their features and working mechanisms better. Finally, some key challenges associated with fire warning materials/sensors are highlighted, following which future perspectives and opportunities are proposed.
Scutellarin, an active component of flavonoid, displays a variety of physiological actions and has been applied for the treatment of diverse diseases including hypertension and cerebral infarction as ...well as cerebral thrombosis. In recent time, Scutellarin has been demonstrated to possess the anticancer activity. But the biological significance of Scutellarin in bladder cancer (BC) remains to be elucidated. In the current study, we explored the specific effect of Scutellarin on BC progression. We found that Scutellarin inhibited hypoxia‐induced BC cell migration and invasion in vitro as well as suppressed hypoxia‐induced BC metastasis in vivo. Moreover, Scutellarin significantly reversed hypoxia‐promoted epithelial‐mesenchymal transition (EMT) in BC cells and the PI3K/Akt and MAPK pathways were implicated in the suppressive effect. Taken together, we suggested the potential value of Scutellarin as a novel anticancer agent for BC treatment.
Scutellarin inhibited hypoxia‐induced bladder cancer (BC) cell migration and invasion in vitro as well as suppressed hypoxia‐induced BC cell metastasis in vivo. Moreover, Scutellarin significantly reversed hypoxia‐induced EMT in BC cells and the PI3K/Akt and MAPK pathways were implicated in the suppressive effect.
A graphene oxide (GO)-based smart fire alarm sensor (FAS) has gained rapidly increasing research interest in fire safety fields recently. However, it still remains a huge challenge to obtain ...desirable GO-based FAS materials with integrated performances of mechanical flexibility/robustness, harsh environment-tolerance, high-temperature resistance, and reliable fire warning and protection. In this work, based on bionic design, the supermolecule melamine diborate (M·2B) was combined with GO nanosheets to form supramolecular cross-linking nanosystems, and the corresponding GO-M·2B (GO/MB) hybrid papers with a nacre-like micro/nano structure were successfully fabricated via a gel-dry method. The optimized GO/MB paper exhibits enhanced mechanical properties, e.g., tensile strength and toughness up to ∼122 MPa and ∼1.72 MJ/m3, respectively, which is ∼3.5 and ∼6.6 times higher than those of the GO paper. Besides, it also shows excellent structural stability even under acid/alkaline solution immersion and water bath ultrasonication conditions. Furthermore, due to the presence of promoting reduction effect and atom doping reactions in GO network, the resulting GO/MB network displays exceptional high-temperature resistance, sensitive fire alarm response (∼0.72 s), and ultralong alarming time (>1200 s), showing promising fire safety and protection application prospects as desirable FAS and fire shielding material with excellent comprehensive performances. Therefore, this work provides inspiration for the design and fabrication of high-performance GO-based smart materials that combine fire shielding and alarm functions.
Lignin grafted N, N′-methylene-bisacrylamide (LM) was copolymerized with acrylic acid (AA) to fabricate lignin based poly (acrylic acid) (LBPAA) nanocomposites, and organo-montmorillonite (OrgMMT) ...was uniformly dispersed in LBPAA by ultrasonic method. The water absorbency in KCl solution was 302.9 g/g for LBPAA/OrgMMT (3 wt% OrgMMT, 43.65 wt% LM, and 53.35 wt% poly(acrylic acid) (PAA)), higher than PAA/OrgMMT (104.5736 g/g), and PAA (131.8 g/g). The Pb2+ adsorption for LBPAA/OrgMMT was demonstrated to be pH-dependent and followed Freundlich multilayer adsorption, with the removal following a pseudo-second-order kinetic model. The Pb2+ absorption capacity of LBPAA (PAA 48.50/48.50 LM)/OrgMMT (3 wt%) was 1.0803 mmol·g−1, the highest among the composites. When the mole ratio of Na+ and Pb2+ was less than 0.21, the Pb2+ adsorption capacity of LBPAA/OrgMMT decreased slightly. The negative ΔG0 indicated that the Pb2+ adsorption process for composite hydrogel and PAA was spontaneous. XPS analysis data indicated that Pb2+ ions formed Pb-O bonds by hydroxyl groups and carboxyl groups for efficient lead ion adsorption. This study demonstrates that LBPAA/OrgMMT can be used as a water retention agent with salt tolerance and as an adsorbent for removing Pb2+ ions from industrial waste water.
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•OrgMMT composite was uniformly dispersed in LBPAA by the assistance of ultrasonic vibration.•LBPAA/OrgMMT with pores improved salt resistance adsorption rate and efficiency of Pb (II) ions.•LBPAA/OrgMMT nanocomposites showed multilayer adsorption of Pb (II) ions.
C‐type cytochromes located on the outer membrane (OMCs) of genus Shewanella act as the main redox‐active species to mediate extracellular electron transfer (EET) from the inside of the outer membrane ...to the external environment: the central challenge that must be met for successful EET. The redox states of OMCs play a crucial role in dictating the rate and extent of EET. Here, we report that the surface wettability of the electrodes strongly influences the EET activity of living organisms of Shewanella loihica PV‐4 at a fixed external potential: the EET activity on a hydrophilic electrode is more than five times higher than that on a hydrophobic one. We propose that the redox state of OMCs varies significantly at electrodes with different wettability, resulting in different EET activities.
Hydrophobic or hydrophilic: The electron flow from living microbes can be simply regulated by altering the surface wettability of the electrodes at a fixed external potential. The extracellular electron transfer activity on a hydrophilic electrode is shown to be more than five times higher than that on a hydrophobic one. TCA=tricarboxylic acid.
Brain microvascular endothelial cells (BMEC) are highly complex regulatory cells that communicate with other cells in the neurovascular unit. Cerebral ischemic injury is known to produce detectable ...synaptic dysfunction. This study aims to investigate whether endothelial cells in the brain regulate postnatal synaptic development and to elucidate their role in functional recovery after ischemia. Here, we found that in vivo engraftment of endothelial cells increased synaptic puncta and excitatory postsynaptic currents in layers 2/3 of the motor cortex. This pro-synaptogenic effect was blocked by the depletion of VEGF in the grafted BMEC. The in vitro results showed that BMEC conditioned medium enhanced spine and synapse formation but conditioned medium without VEGF had no such effects. Moreover, under pathological conditions, transplanted endothelial cells were capable of enhancing angiogenesis and synaptogenesis and improved motor function in the ischemic injury model. Collectively, our findings suggest that endothelial cells promote excitatory synaptogenesis via the paracrine factor VEGF during postnatal development and exert repair functions in hypoxia-ischemic neonatal mice. This study highlights the importance of the endothelium-neuron interaction not only in regulating neuronal development but also in maintaining healthy brain function.
•Endothelial VEGF promotes synaptogenesis and neurotransmission.•Endothelia promote vascular and neuronal network construction after stroke.•Endothelia improve motor deficits in ischemic neonatal mice.
Background
This meta-analysis was designed to systematically assess the effectiveness and safety of hyperthermic intraperitoneal chemotherapy (HIPEC) combined with surgery for different stages of ...advanced gastric cancer (AGC) during the last 12 years.
Methods
The Cochrane Library, PubMed, Embase, Web of Science, and China National Knowledge Infrastructure (CNKI) were searched online, and papers were retrieved from other sources. Next, randomized controlled trials (RCTs) and high-quality nonrandomized controlled trials (NRCTs) were selected for this analysis. The meta-analysis was conducted with RevMan5.4 software.
Result
The 10 RCTs and 13 NRCTs selected for the study included 1892 patients. The overall survival rates were higher in the HIPEC group at 1 year (risk ratio RR, 0.52;
P
= 0.004) and 3 years (RR, 0.63;
P
< 0.00001) than in the control group for the patients without peritoneal cancer, and the HIPEC group had a significant reduction in the recurrence rate (RR, 0.60;
p
< 0.00001). Among the patients with peritoneal carcinomatosis (PC), the HIPEC group had significantly higher overall survival rates at 1 year (RR, 0.62;
P
= 0.00001), 2 years (RR, 0.85;
P
= 0.002), and 3 years (RR, 0.87;
P
= 0.0001), with an increase in the overall median survival time of 4.67 months. The two groups showed no statistically significant difference in terms of complications for patients with PC (RR, 1.03; P = 0.93) or without PC (RR, 1.15;
P
= 0.51).
Conclusion
For local AGC without PC, standard surgery combined with prophylactic HIPEC could prolong survival and reduce the recurrence rate without more complications. The prognosis of this treatment strategy for patients with PC is closely related to patient selection. Complete cytoreduction combined with therapeutic HIPEC could prolong survival.
Poles assignment problem for second-order linear periodic system by using periodic proportion-plus-derivative (PD) state-feedback is considered in this paper. The poles assignment problem via ...periodic PD state-feedback in a class of discrete periodic second-order linear systems can be transformed into the problem of solving a class of constrained discrete periodic regulator equations. A complete parametric approach to poles assignment via periodic PD state-feedback is proposed based on the solutions to the discrete periodic regulator matrix equations. Based on the proposed parametric method, the consideration of the minimization problem and the robust problem of the plant system are proposed. Two numerical examples are presented to illustrate the effectiveness of the proposed approaches.
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