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Electroacupuncture has been widely used to treat cognitive impairment after cerebral ischemia, but the underlying mechanism has not yet been fully elucidated. Studies have shown that autophagy plays an important role in the formation and development of cognitive impairment, and the phosphoinositide 3-kinase(PI3 K)/Akt signaling pathway plays an important role in autophagy regulation. To investigate the role played by the PI3 K/Akt signaling pathway in the electroacupuncture treatment of cerebral ischemia/reperfusion rat models, we first established a rat model of cerebral ischemia/reperfusion through the occlusion of the middle cerebral artery using the suture method. Starting at 2 hours after modeling, electroacupuncture was delivered at the Shenting(GV24) and Baihui(GV20) acupoints, with a dilatational wave(1–20 Hz frequency, 2 mA intensity, 6 V peak voltage), for 30 minutes/day over 8 consecutive days. Our results showed that electroacupuncture reduced the infarct volume in a rat model of cerebral ischemia/reperfusion injury, increased the mRNA expression levels of the PI3 K/Akt signaling pathwayrelated factors Beclin-1, mammalian target of rapamycin(mTOR), and PI3 K, increased the protein expression levels of phosphorylated Akt, Beclin-1, PI3 K, and mTOR in the ischemic cerebral cortex, and simultaneously reduced p53 mRNA and protein expression levels. In the Morris water maze test, the latency to find the hidden platform was significantly shortened among rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. In the spatial probe test, the number of times that a rat crossed the target quadrant was increased in rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. Electroacupuncture stimulation applied to the Shenting(GV24) and Baihui(GV20) acupoints activated the PI3 K/Akt signaling pathway and improved rat learning and memory impairment. This study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Henan University of Traditional Chinese Medicine, China(approval No. 8150150901) on March 10, 2016.  相似文献   
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Wang  Huijie  Niu  Feng  Fan  Wei  Shi  Jimin  Zhang  Jihong  Li  Bing 《Metabolic brain disease》2019,34(5):1299-1311

It is well-known that in ischemia-induced hypoxia, hypoxia-inducible factor -1α (HIF-1α) is critical in triggering expression of its downstream target genes to produce several products, such as erythropoietin (EPO), vascular endothelial growth factor (VEGF), nitric oxide synthesis (NOS), glucose transportor-1 (GLUT-1), insulin-like growth factor (IGF), which further promote erythropoiesis, angiogenesis, vasodilation and capitalization of glucose to overcome hypoxia. Meanwhile, as the factors with opposite effects on blood vessels, endothelin-1 (ET-1) and brain natriuretic peptide (BNP) also stand out strikingly in ischemic pathophysiology. To this day, several preconditioning manners have been used to induce tolerance to ischemia. During our research, exercise preconditioning was applied and it was demonstrated that HIF-1α triggered expression of ET-1 and BNP, which confirmed their downstream target genes for HIF-1α. And ET-1 may influcence expression of BNP to some degree but not the only factor which regulates BNP expression. Therefore, our findings suggest exercise preconditioning may provide protection to the ischemic brain tissue via HIF-1α which in turn increases expression of BNP to cause vasodilation in cooperation with some other factors, such as VEGF and EPO, to increase the blood flow in the ischemic area and then relieve the injuries induced by ischemia.

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Although sphingomyelins known to be are lipid constituents of the plasma membrane in vertebrates, much remains obscure about the metabolism of sphingomyelins in insects. With ultra performance liquid chromatography‐time‐of‐flight‐tandem mass spectrometry analysis, we revealed for the first time that sphingomyelins are abundant in Nilaparvata lugens (Stål), the brown planthopper (BPH), and their biosynthesis is carried out by sphingomyelin synthase‐like protein 2 (SMSL2), which is homologous to sphingomyelin synthase‐related protein (SMSr). Unlike other insect species, high concentrations of sphingomyelins rather than ceramide phosphoethanolamines exist in the BPH. Two putative genes, which are homologous to SMSr, are named Nilaparvata lugens SMS‐like 1 (NlSMSL1) and 2 (NlSMSL2). Knockdowns of both NlSMSL2 and NlSMSL1 were conducted but only the first decreased concentrations of sphingomyelins in the BPH, indicating that NlSMSL2 plays a role in the biosynthesis of sphingomyelins. Real‐time quantitative PCR analysis revealed both NlSMSL1 and NlSMSL2 are highly expressed in BPH adults, with NlSMSL1 specifically highly expressed in reproductive organs (ovaries and testes) whereas NlSMSL2 was highly expressed in the malpighian tubules. The knockdown of NlSMSL1 or NlSMSL2 increased BPH female body weight but not that of males, suggesting sex‐specific roles for SMSLs in influencing BPH body weight. The results suggest that NlSMSL2 catalyses the synthesis of sphingomyelins and maintains female BPH body weight through alteration of sphingolipid content.  相似文献   
66.
Systemic sclerosis (SSc) is an autoimmune disease mainly characterized by persistent inflammation and fibrosis. The receptor tyrosine kinase (RTK) signal pathway plays an important role in the process of SSc, and Grb2‐associated binding protein (GAB) is crucial in activating RTK signalling. A previous study found elevated levels of GAB1 in bleomycin (BLM)‐induced fibrotic lungs, but the effects of GAB1 in SSc remain unclear. Our aim was to investigate whether GAB1 was dysregulated and its potential role in SSc. Compared with healthy donors, we found GAB1 expression was 1.6‐fold higher in peripheral blood mononuclear cells (PBMC), 2.5‐fold higher in CD4 + T cells, and 2‐fold higher in skin from of SSc patients (P < .01). At the same time, the levels of type one collagen (COLI) were also significantly increased (1.8‐fold higher) in SSc skin. Additionally, BLM‐induced SSc mice showed mRNA levels of Gab1 2‐fold higher than saline‐treated controls, and Gab1 expression correlated positively with collagen content. A further in vitro study showed silencing of GAB1 suppressed inflammatory gene expression in TNF‐α induced fibroblasts. Additionally, GAB1 deficiency prominently inhibited cell proliferation and reduced COLI protein levels in TGF‐β induced fibroblasts. Taken together, these data suggest that GAB1 has a relatively high expression rate in SSc, and knockdown of GAB1 may attenuate SSc by stimulating inflammatory and fibrotic processes.  相似文献   
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Although patients with rosacea often consult dermatologists for dietary factors that might be related to their skin disorders, few studies have been conducted to research the relationship between rosacea and dietary factors. The purpose of this study was to evaluate the potential relationship between rosacea and diet among the large Chinese population with rosacea, which would provide dietary guidelines for patients with rosacea. A multicenter case–control study was conducted. The feeding frequency 2 years before the occurrence of rosacea was collected by standardized questionnaires. Multiple logistic regression analysis was used to calculate risks related to the diet. One thousand three hundred and forty‐seven patients with rosacea and 1290 controls were enrolled in our study. We found that high‐frequency intake of fatty food and tea presented a positive correlation with rosacea, while high‐frequency dairy product intake showed significant negative correlation with rosacea. Sweet food, coffee and spicy food appeared to be independent of any subset of rosacea in our study. However, high‐frequency dairy product intake showed a borderline beneficial effect on rosacea severity. We further analyzed the correlation between diet and the subtype of rosacea. We found that high‐frequency fatty intake was associated with erythematotelangiectatic rosacea (ETR) and phymatous rosacea, while high‐frequency tea intake was only associated with ETR. In addition, high‐frequency dairy product intake showed negative correlations with ETR and papulopustular rosacea. Rosacea is associated with some dietary factors, and our study is valuable in establishing dietary guidelines to prevent and improve rosacea.  相似文献   
68.
In order to solve the problem of long-term (>9 months) efficacy in the treatment of Alzheimer''s disease (AD) by conventional therapy (CT), a staged and multiply-targeted sequential therapy based on the evolvement of patterns (STEP) was developed. Its main innovations include: (1) the time order of evolution of patterns defined by Chinese medicine (CM) in AD was found, that is, "the orderly pattern evolution starting from Shen (Kidney) deficiency, progressing to phlegm, stasis and fire, and worsening to severe toxin as well as functional collapse"; (2) the cascade hypothesis of Shen deficiency in AD and its sequential therapy based on Shen-reinforcing was proposed, that is, "reinforcing Shen in the early stage and throughout the whole process, resolving phlegm, activating blood and purging fire in the middle stage, detoxifying and replenishing vitality to stop the collapse in the advanced stage", and through meta-analysis, clinical drug use was optimized, thus the leap from "inferential selection" to "evidence-based selection" was realized; (3) the STEP regimen combined with CT maintained cognitive and behavioral stability in AD patients for at least 12 months, with cognitive enhancement and behavioral synergy after 9 months, and cognitive benefit was superior to CT at 9, 12, 15, 18, 21, and 24 months, respectively. The 2-year cognitive improvement rate was increased by 25.64% (P=0.020) and the cognitive deterioration rate was decreased by 48.71% (P=0.000). Among them, the cognitive and functional benefits of Shen-reinforcing therapy for very early AD (350 cases) for 1 year were better than the placebo (P<0.001), and the dementia conversion rate was reduced by 8.85% (P=0.002). The behavioral symptomatic relief of patients with vascular dementia received fire-purging therapy (540 cases) was superior to those received CT (P=0.016). These data suggested that the STEP regimen has synergistic effects on CTs at least in terms of cognitive benefit, and the earlier the use, the greater the benefit will have. Therefore, the STEP regimen should be considered as one of the clinical options, particularly for the dearth of effective pharmaceutical or immunological interventions that are currently available for AD.  相似文献   
69.
This study was aimed at assessing the effects of urokinase (UK) in combination with ultrasound and microbubbles in in vitro and in vivo thrombolytic therapy for the treatment of deep vein thrombosis (DVT). Thrombi with formation times of 1, 3, 7, 14 and 21 d were used for thrombolysis. Forty-five adult mongrel dogs were used to evaluate thrombosis in vivo. Both in vitro and in vivo analyses revealed that UK?+?microbubbles had the best effect among the combinations. Thrombolysis <7 d was more effective at a thrombolysis rate of about 50%, but the thrombolytic effect of thrombi >7 d was poor at thrombolysis rates <30%. Ultrasound?+?UK significantly increased the thrombolysis rate of thrombi <7 d. These results suggest that the combination of ultrasound with microbubble contrast agents and UK may have a synergistic effect on thrombolysis.  相似文献   
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