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31.
The present study focused on the evaluation of antibacterial property of silver nanoparticles (AgNPs) synthesized using mango flower extract. The morphology of the synthesized AgNPs was observed under transmission electron microscopy and the particles have shown spherical shape in the range of 10–20 nm. X-ray powder diffraction analysis confirmed the crystalline nature of the AgNPs. The atomic percentage of the Ag element in the nanoparticles was about 7.58% which is greater than the other elements present in the sample. The AgNPs showed extensive lethal effect on both Gram-positive (Staphylococcus sp.) and Gram-negative (Klebsiella sp., Pantoea agglomerans, and Rahnella sp.) bacteria. The extensive lethal effect of AgNPs against clinically important pathogens demonstrated that the mango flower mediated AgNPs could be applied as potential antibacterial agent to control the bacterial population in the respective industries.  相似文献   
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Magnetic core shell nanoparticles are composed of a highly magnetic core material surrounded by a thin shell of desired drug, polymer or metal oxide. These magnetic core shell nanoparticles have a wide range of applications in biomedical research, more specifically in tissue imaging, drug delivery and therapeutics. The present review discusses the up-to-date knowledge on the various procedures for synthesis of magnetic core shell nanoparticles along with their applications in cancer imaging, drug delivery and hyperthermia or cancer therapeutics. Literature in this area shows that magnetic core shell nanoparticle-based imaging, drug targeting and therapy through hyperthermia can potentially be a powerful tool for the advanced diagnosis and treatment of various cancers.  相似文献   
35.
Dyskinesia, a motor complication caused by prolonged administration of the antiparkinsonian drug l-3,4-dihydroxyphenylalanine (l-DOPA), is accompanied by activation of cAMP signaling and hyperphosphorylation of the dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32). Here, we show that the abnormal phosphorylation of DARPP-32 occurs specifically in medium spiny neurons (MSNs) expressing dopamine D1 receptors (D1R). Using mice in which DARPP-32 is selectively deleted in D1R-expressing MSNs, we demonstrate that this protein is required for l-DOPA-induced activation of the extracellular signal-regulated protein kinases 1 and 2 and the mammalian target of rapamycin complex 1 (mTORC1) pathways, which are implicated in dyskinesia. We also show that mutation of the phosphorylation site for cAMP-dependent protein kinase on DARPP-32 attenuates l-DOPA-induced dyskinesia and reduces the concomitant activations of ERK and mTORC1 signaling. These studies demonstrate that, in D1R-expressing MSNs, l-DOPA-induced activation of ERK and mTORC1 requires DARPP-32 and indicates the importance of the cAMP/DARPP-32 signaling cascade in dyskinesia.  相似文献   
36.
滇池流域居民-农田混合区面源污染控制集成技术   总被引:4,自引:0,他引:4  
以滇池流域六甲乡金家村为研究对象,该区为城郊典型的居民-农田混合区,总面积14万m2,其中居民区面积为7.7万m2,常驻人口780口,区内有一家约120头的养猪场,一个具有9家洗涤企业的金家村工业园区,居民区和养殖、工业废水直接排向就近的90%种植韭菜的农田区。针对该区村庄-小企业-农田-养殖业呈复区分布,污染源复杂,雨污混流污染严重,污水管网建设滞后,化肥施用过量,沟渠湿地系统破碎等现状,研发出兼顾水质净化和农田排灌的居民-农田混合区面源污染控制集成技术,包括改良化粪池与组合基质床,生态支沟,生态干渠,A/O生物处理系统,复合人工湿地等污水处理技术,以及农田内部的节氮控磷技术,如精确施肥,施用硝化抑制剂抑制氮向水体迁移,垄沟内浮萍的氮磷滞留与养分循环利用。通过12个月的连续监测表明:在非降雨日负荷为500m3/d的工况下,改良化粪池与组合基质床对COD,TP,TN的去除率分别为61.3%,50.50%,44.4%;A/O生物处理系统对COD,TP,TN的去除率分别为65.8%,55.2%,55.2%;生态支沟由于进水量小浓度高,水力停留时间长,其对COD,TP,TN的去除率均比生态干渠的高,分别高29.0%,17.5%,28.4%;系统末端复合人工湿地对污染物质的去除效果分别为COD 50.6%,TP44.9%,TN36.4%。一年内依托集成技术建设的生态工程去除污染物的总量为COD 143.71t,TP2.43t和TN16.99t,对氮磷的去除量相当于一座负荷为350~620m3/d 的市政污水处理厂去除的量。经济效益分析得出,整个系统日耗电量18度,由一名工人即可管护。传统施肥减量20%+叶面肥,每年每公顷可减少氮肥投入约2400元,增加叶面肥投入约500元,减少收入约1300元,合计增收3200元。浮萍滞留与养分循环利用,每年每公顷韭菜地相当于少施用151kg尿素和93kg过磷酸钙的氮磷含量。施用DCD和元素硫,淋溶水中硝态氮的浓度降低了59.2%,测渗水中则降低了62.2%。可见,居民-农田混合区面源污染控制集成技术不但可以有效去除污染物,而且在保证产量的情况下,增加农民收益。技术适用于城市郊区、城乡结合部及广大农村等城市污水管网未覆盖地区推广使用,具有巨大的推广潜力。  相似文献   
37.
Zinc tetraaminophthalocyanine-Fe3O4 nanoparticle composites were prepared by organic-inorganic complex technology and characterized. It has been proved that the ZnTAPc dispersed randomly onto the surface of Fe3O4 nanoparticles to form molecular dispersion layer and there was a relatively strong bond between central zinc cation and oxygen. The nanoparticle composite took the shape of roundish spheres with the mean diameter of about 15 nm. Active amino groups of magnetic carriers could be used to bind laccase via glutaraldehyde. The optimal pH for the activity of the immobilized laccases and free laccase were the same at pH 3.0 and the optimal temperature for laccase immobilization on ZnTAPc-Fe3O4 nanoparticle composite was 45 degrees. The immobilization yields and K(m) value of the laccase immobilized on ZnTAPc-Fe3O4 nanoparticle composite were 25% and 20.1 microM, respectively. This kind of immobilized laccase has good thermal, storage and operation stability, and could be used as the sensing biocomponent for the fiber optic biosensor based on enzyme catalysis.  相似文献   
38.
The mammalian target of rapamycin complex 1 (mTORC1) is a master regulator of cell growth and proliferation. Recent studies have suggested that constitutive activation of mTORC1 in normal cells could lead to malignant tumor development in several tissues. However, the mechanisms of mTORC1 hyperactivation to promote the growth and metastasis of breast or other cancers are still not well characterized. Here, using a new inducible deletion system, we show that deletion of Tsc1 in mouse primary mammary tumor cells, either before or after their transplantation, significantly increased their growth in vivo. The increase in tumor growth was completely rescued by rapamycin treatment, suggesting a major contribution from mTORC1 hyperactivation. Interestingly, glucose starvation-induced autophagy, but not amino acid starvation-induced autophagy, was increased significantly in Tsc1-null tumor cells. Further analysis of these cells also showed an increased Akt activation but no significant changes in Erk signaling. Together, these results provide insights into the mechanism by which hyperactivation of mTORC1 promotes breast cancer progression through increasing autophagy and Akt activation in vivo.  相似文献   
39.
Last decade, the Government of Catalonia have urged an integrated care strategy for planning the care model to older populations living with frailty, multimorbidity and advanced illnesses. Based on international evidence that was reviewed by a group of experts from the Catalan Society of Gerontology and Geriatrics, we summarised some recommendation to adapt hospital-at-home care to older populations in our system. We defined Comprehensive Geriatric Assessment (CGA) hospital-at-home (HaH) as a specialised home hospitalisation service formed by interdisciplinary teams, characterised by using the clinical methodology of CGA, and by adapting geriatric units’ protocols for the provision of person-centred care at home. Main benefits of CGA-HaH in these populations are: response to heath crises according to individualised care plans based on the situational diagnosis carried out by Primary Care teams; provision of a comprehensive health and social approach tailored to the complexity of cases and situations; and adaptation of multipurpose hospitalisation, by working on different person-centred care, aspects, such as caregivers support on care provision, focusing on function or home adaptation.  相似文献   
40.
Rapid growth in nanotechnology toward the development of nanomedicine agents holds massive promise to improve therapeutic approaches against cancer. Nanomedicine products represent an opportunity to achieve sophisticated targeting strategies and multifunctionality. Nowadays, nanoparticles (NPs) have multiple applications in different branches of science. In recent years, NPs have repetitively been reported to play a significant role in modern medicine. They have been analyzed for different clinical applications, such as drug carriers, gene delivery to tumors, and contrast agents in imaging. A wide range of nanomaterials based on organic, inorganic, lipid, or glycan compounds, as well as on synthetic polymers has been utilized for the development and improvement of new cancer therapeutics. In this study, we discuss the role of NPs in treating cancer among different drug delivery methods for cancer therapy.  相似文献   
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