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51.
Paper-based sensing platforms hold promise in human physiological health monitoring, soft robots, and indoor environment monitoring, owing to their cost effectiveness, flexibility, disposability, and biodegradability. However, most of the existing paper-based sensors require complex fabrication procedures which are also associated with high-cost. Herein, we report a simple yet effective manufacturing process of paper-based carbonaceous sensors based on a laser direct writing (LDW) method. Specifically, carbonaceous pressure, temperature, and humidity sensors on cardboard are developed for human physiological signal monitoring and indoor environment monitoring. Due to the external force induced compaction of the layered carbon flakes, the LDW pressure sensor array has a sensitivity of ∼−0.563 kPa−1, a broad sensing range (0.009–50 kPa), and a high mechanical durability (over 11 000 cycles), all of which are promising for human health monitoring. The LDW-temperature and humidity devices have sensitivities of −0.002/°C and 36.75 fF per %RH, respectively. A prototype is developed using cardboard integrated with temperature and humidity sensors, which not only serves as an ornament to decorate homes but also works as a sensor platform for indoor environment monitoring. Systematic investigation of the LDW manufacturing process, sensing mechanisms, and sensor design and evaluation illustrates the key aspects of carbonaceous sensors.Carbonaceous sensors on cardboard can be used for human health and indoor environment monitoring. 相似文献
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Loading rates during walking in adolescents with type II osteonecrosis secondary to pelvic osteotomy
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Ting‐Ming Wang Kuan‐Wen Wu Ching‐Ru Chen Shih‐Wun Hong Tung‐Wu Lu Ken N. Kuo Shier‐Chieg Huang 《Journal of orthopaedic research》2016,34(12):2199-2206
Although Pemberton osteotomy has shown a high success rate even in older children, the occurrence of osteonecrosis (ON) remains one of the most severe complications, leading to premature osteoarthritis. Patients with type II ON are characterized by a valgus deformity of the proximal femur with altered musculoskeletal conditions, affecting the ability to attenuate or sustain the impulsive loading from the ground reaction force. It remains unclear whether these conditions also predispose these patients to harmful impulsive loadings. This study aimed to bridge the gap by measuring the loading rates in the lower limbs during level walking in adolescents who were treated during their infancy for unilateral developmental dysplasia of the hip by a pelvic osteotomy, with or without having developed type II ON. Patients with type II ON were found to display increased loading rates, not only at both the affected and unaffected hip, but also at other joints of the affected limb during level walking when compared to patients without ON changes (p < 0.05). These results suggest that patients with type II ON may be at a higher risk of developing premature hip osteoarthritis that is closely related to abnormal loading rates during gait. It is suggested that regular monitoring of joint loading rates in patients with type II ON is necessary for early identification of damaging loadings, and that early intervention aimed at reducing these loadings should be considered. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2199–2206, 2016. 相似文献
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Analysis of the action of euxanthone, a plant-derived compound that stimulates neurite outgrowth 总被引:1,自引:0,他引:1
We have investigated the neurite growth-stimulating properties of euxanthone, a xanthone derivative isolated from the Chinese medicinal plant Polygala caudata. Euxanthone was shown to exert a marked stimulatory action on neurite outgrowth from chick embryo dorsal root ganglia explanted in collagen gels, in the absence of added neurotrophins. It was also shown to promote cell survival in explanted chick embryo ganglia, and to stimulate neurite outgrowth from isolated adult rat primary sensory neurons in vitro. The further finding that euxanthone stimulates neurite outgrowth from explants of chick embryo retina and ventral spinal cord suggests an action on signaling pathways downstream of neuronal receptors for specific neurotrophic factors. Consistent with this, euxanthone did not promote neurite outgrowth from non-transfected PC12 cells, or from PC12 cells transfected with TrkB or TrkC, under conditions in which these cells extended neurites in response to, respectively, the neurotrophins nerve growth factor, brain-derived neurotrophic factor and neurotrophin 3. Western blot analysis of euxanthone-stimulated dorsal root ganglion explants showed that expression of phospho-mitogen-activated protein (MAP) kinase was up-regulated after 1 h of euxanthone-treatment. Inhibition of the MAP kinase pathway using PD98059, a specific inhibitor of MAP kinase kinase, blocked all euxanthone-stimulated neurite outgrowth. However, analysis of phospho-Akt expression indicated that the phosphatidylinositol-3 kinase-Akt pathway, another major signaling pathway engaged by neurotrophins, is not significantly activated by euxanthone. These results suggest that euxanthone promotes neurite outgrowth by selectively activating the MAP kinase pathway. 相似文献
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Kuan Chen Junbin He Zhimin Hu Wei Song Liyan Yu Kai Li 《Journal of Asian natural products research》2018,20(7):615-623
AbstractGlycosylation is an effective approach to improve the druggability of natural products by increasing their water solubility. In this work, we report the glycosylation of oleanane-type triterpenoids by a recombinant microbial glycosyltransferase YjiC1. A preliminary screening test indicated YjiC1 exhibited robust capabilities for O-glycosylation of triterpenoids, based on LC/MS analysis. Among the products, two new compounds (2a and 3a), together with a known one (1a), were isolated and characterized. These products exhibited improved water solubility, and 3a showed moderate anti-HIV activities at 100 μM. This reaction provides a facile and efficient approach to synthesize the glucosides of triterpenoids. 相似文献
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Coronarin D induces apoptotic cell death through the JNK pathway in human hepatocellular carcinoma
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![点击此处可从《Environmental toxicology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Hui‐Wen Lin Ming‐Ju Hsieh Chao‐Bin Yeh Kuan‐Chun Hsueh Yi‐Hsien Hsieh Shun‐Fa Yang 《Environmental toxicology》2018,33(9):946-954
Coronarin D, a diterpene derived from the rhizomes of Hedychium coronarium, has been used to treat inflammatory diseases. Coronarin D can exert strong anticancer effects through cell growth prevention and cell cycle arrest in many cancer cells. In this study, we investigated the molecular mechanism through which coronarin D suppresses cell proliferation and triggers cell death in human hepatocellular carcinoma (HCC) cells. Treatment of Huh7 and Sk‐hep‐1 cells with coronarin D resulted in a significantly increased loss of mitochondrial membrane potential, leading to the cleavage and activation of caspase‐9, caspase‐8, and caspase‐3 and changes in Bax, Bcl‐2, and Bcl‐xL protein levels. Coronarin D significantly induced autophagy by increasing the expression of Beclin‐1 and LC3‐II and reducing the expression of p62. Moreover, Huh7 and Sk‐hep‐1 cells exposed to coronarin D had decreased expression of phosphorylated AKT, p38, and ERK and increased expression of phosphorylated JNK. Exposure of cells to the JNK‐specific inhibitor SP600125 attenuated the apoptotic effects of coronarin D. Taken together, this is the first study to report that coronarin D may effectively inhibit cell growth through apoptosis. We have provided evidence indicating that coronarin D induces cell death through the upregulation of JNK mitogen‐activated protein kinases in human HCC cells. 相似文献
58.
电刺激小脑顶核对持续局灶性脑缺血时钙蛋白酶活性的影响 总被引:1,自引:1,他引:1
目的观察电刺激小脑顶核(FN)对持续局灶性脑缺血钙蛋白酶活性的影响,以阐明其神经保护作用机制。方法健康雄性Wistar大鼠,随机分为假手术组(PO)、FN刺激假手术组(PO-FN)、持续缺血组(PI)及持续缺血-FN刺激组(PI-FN),后两组又分为缺血1,3,6,12及24h组。建立大鼠电刺激FN及持续局灶性脑缺血模型,应用Western印迹半定量各组缺血核心区Mr=150000FBDP含量(表示钙蛋白酶活性),并应用尼氏体染色对缺血核心区神经元数量及形态进行分级评分。结果PO组及PO-FN组钙蛋白酶活性相似(P>0.05),处于低水平。PI组钙蛋白酶活性从缺血1h犤(3670±600)A/μg总蛋白犦开始即显著增高(t=6.338,P<0.001),以后随着缺血时间延长,钙蛋白酶活性不断增高,直至缺血24h犤(9180±360)A/μg总蛋白犦仍有持续增高趋势(缺血12,24h,t=14.673,16.632,P<0.001)。PI-FN组随着缺血时间的延长,钙蛋白酶活性从缺血1h犤(2510±460)A/μg总蛋白犦也开始增高,以后随着缺血时间延长,钙蛋白酶活性不断增高,但各时点组与其相应PI组相比,其增高程度明显减低,差别具有显著意义(缺血1,24h,t=1.875,2.134,P<0.05)。PO组及PO-FN组神经元形态及数量正常,评分均为0分。PI组从缺血1h(0.8±0.3)开始,神经元形态、数量即出现轻度改变,其评分增高(z=2.443,P<0.01),以 相似文献
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急性纤维素性机化性肺炎是一种罕见类型的间质性肺疾病,其病因及相关发病机制尚不明确,国内外关于此项疾病的研究及报道较少,亦无明确的诊断标准与规范的治疗方案。报道多为感染或药物不良反应相关,对过敏所致的此类疾病报道罕见,本文总结了成功诊治的一例此类患者相关诊疗经过,并做相关文献复习,以提高对该疾病的认识,避免误诊漏诊,同时提供一治疗方案供临床参考。 相似文献