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61.
Prabhakaran Dhanasekaran Swaminathan Rajavarman Sivasuriyanarayanan Vinod Selvaganesh Santoshkumar Dattatray Bhat 《Materials》2021,14(9)
Nanocrystalline platinum with different morphologies is synthesized via electrochemical deposition technique. The nucleation mechanism and its structural effect over the electrodeposited Pt on carbon electrodes have been systematically studied. Powder X-ray diffraction, X-ray photoelectron spectroscopy, and field-emission scanning electron microscopy are employed to study nucleation, oxidation states, and Pt structure growth on a carbon electrode. This study reports significant development of Pt metal nanoparticles with different morphologies such as a sphere, flower, core-flower, and rod-like structure directly fabricated on carbon electrode while tuning the deposition parameters such as current density, time, temperature, pH during the deposition process. The proposed electrochemical route represents a superior fabrication procedure for large-scale electrode fabrication compared to a conventional method for preparing membrane electrode assemblies for fuel cell stacks. 相似文献
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Rosario Gulias-Cañizo Anell Lagunes-Guillén Arturo González-Robles Erika Sánchez-Guzmán Federico Castro-Muñozledo 《Burns : journal of the International Society for Burn Injuries》2019,45(2):398-412
Background
Since recent reports have shown that (-)-Epigallocatechin-3-gallate (EGCG) could be used for treating proliferative and inflammatory disorders, we explored its use for the management of corneal chemical burns.Materials and methods
Initially, EGCG was assayed on the rabbit corneal epithelial cell line RCE1(5T5) to establish the best testing conditions, and to avoid unwanted outcomes in the experimental animals. Then, we studied its effects on cell proliferation, cell cycle progression and cell differentiation. Afterwards, we instilled EGCG in experimental grade II corneal alkali burns in mice, three times a day up to 21 days, and evaluated by slit lamp examination and histological sections of corneal epithelial, corneal endothelial and stromal edema, as well as the presence of inflammatory cells and neovascularization.Results
EGCG reduced cell growth and led to a decline in the proportion of proliferative cells in a concentration dependent manner. At 10 μM, EGCG promoted cell differentiation, an effect not related with apoptosis or cytotoxicity. When 10 μM EGCG was instilled in corneal alkali burns in mice three times a day up to 21 days, EGCG significantly reduced corneal opacity and neovascularization. The improved clinical appearance of the cornea was associated to a controlled epithelial growth; epithelial morphology was similar to that observed in normal epithelium and contrasted with the hyperproliferative, desquamating epithelium observed in control burn wounds. EGCG reduced corneal, stromal and endothelial edema, and wound inflammation.Conclusion
This work constitutes the first evidence for the use of EGCG in the acute phase of a corneal alkali burn, representing a possible novel alternative to improve patient outcomes as an add-on therapy. 相似文献65.
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《Mayo Clinic proceedings. Mayo Clinic》2019,94(7):1321-1329
Immune checkpoint inhibitors are molecules that increase the endogenous immune response against tumors. They have revolutionized the field of oncology. Since their initial approval for the treatment of advanced melanoma, their use has expanded to the treatment of several other advanced cancers. Unfortunately, immune checkpoint inhibitors have also been associated with the emergence of a new subset of autoimmune-like toxicities, known as immune-related adverse events. These toxicities differ depending on the agent, malignancy, and individual susceptibilities. Although the skin and colon are most commonly involved, any organ may be affected, including the liver, lungs, kidneys, and heart. Most of these toxicities are diagnosed by excluding other secondary infectious or inflammatory causes. Corticosteroids are commonly used for treatment of moderate and severe immune-related adverse events, although additional immunosuppressive therapy may occasionally be required. The occurrence of immune-related toxicities may require discontinuation of immunotherapy, depending on the specific toxicity and its severity. In this article, we provide a focused review to familiarize practicing clinicians with this important topic given that the use of immune checkpoint inhibitors continues to increase. 相似文献
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Using JEG-3 and BeWo cells, we examined the effect of “real life” mixtures of polycyclic aromatic hydrocarbons (PAHs), at doses reported in maternal blood (Mix I) and in placental tissue (Mix II), on human chorionic gonadotropin (hCG), placental lactogen (hPL) and placental growth factor (hPLGF) secretion, protein expression and immunolocalization. Additionally, the action of PAH mixtures on basal and hormone-stimulated matrix metalloproteinase-2 (MMP-2), MMP-9 and vascular endothelial growth factor (VEGF) protein expression was evaluated. Under basal conditions, the PAH mixtures increased hCG and decreased hPLGF levels in both cell lines, while hPL expression was stimulated in JEG-3 and inhibited in BeWo. There was no effect on the MMP-2/MMP-9 ratio or VEGF expression. In hormone-stimulated cells, PAH mixtures changed the MMP-2/MMP-9 ratio in JEG-3 cells in favor of MMP-9, while in BeWo MMP-2 was favored. The effect on VEGF expression was cell specific and dependent on the mixture. In hCG-treated cells, only Mix II inhibited VEGF expression in JEG-3 cells. Neither PAH mixtures affected this protein in BeWo cells. In hPL-treated cells, Mix I had a stimulatory effect in JEG-3 cells, while Mix II exerted an inhibitory effect in BeWo cells. In hPLGF-treated cells, Mix II decreased in JEG-3 cells, but in BeWo cells, both mixtures increased VEGF expression. Considering that the evaluated protein hormones play crucial roles in angiogenesis and neovascularization in the placenta, “real life” PAH mixtures by disrupting protein hormones levels, the MMP-2/MMP-9 ratio and VEGF expression can lead to insufficiency and many pregnancy-related disorders. 相似文献
70.
目的:探讨益气通脉饮治疗气虚血瘀型冠心病心绞痛的临床疗效。方法:选取2017年10月—2019年2月烟台业达医院收治的气虚血瘀型冠心病心绞痛的患者90例作为研究对象,根据随机数字表法将所选患者均分为两组,每组各45例,两组的一般资料经统计学方法,差异无统计学意义(P>0.05),因此具有可比性。对照组给予常规西药进行治疗,观察组在对照组治疗基础上给予益气通脉饮治疗,1个月后比较两组临床的疗效,评估治疗前后中医证候、心绞痛症状分级和血脂水平。临床检测的数据通过统计产品与服务解决方案(Statistical Product and Service Solutions,SPSS) 19.0软件进行分析和处理,计量的数据使用平均数±标准差(x±s)表示,采用双侧t检验,计数的数据采用χ~2检验,以%表示,以P<0.05为差异有统计学意义。结果:治疗后,对照组和观察组都有一定疗效,但观察组的改善中医证候总有效率95.56%(43/45),高于对照组的82.22%(37/45),两组比较具有统计学意义(P<0.05);心绞痛的症状总有效率观察组为93.33%(42/45),对照组为77.78%(35/45),两组比较差异有统计学意义(P<0.05);与治疗前相比较,两组治疗后的三酰甘油(Triglyceride,TG)、血清总胆固醇(Serum Total Cholesterol,TC)、高密度脂蛋白胆固醇(High Density Liptein Cholesterol,HDL-C)水平均降低(P<0.05),且观察组治疗后低于对照组(P<0.05),两组治疗后的HDL-C升高(P<0.05),组间比较,差异无统计学意义(P>0.05)。结论:益气通脉饮治疗气虚血瘀型冠心病心绞痛的疗效显著,值得临床进一步研究与推广应用。 相似文献