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681.
Glaucoma is an optic neuropathy in which the degeneration of retinal ganglion cells (RGCs) results in irreversible vison loss. Therefore, neuroprotection of RGCs from glaucomatous afflictions is crucial for glaucoma treatment. In this study, we aimed to investigate the beneficial effects of statins in the protection of RGCs using a rat model. Glaucomatous injury was induced in rats by chronic ocular hypertension (OHT) achieved after performing a circumlimbal suture. The rats were given either statins such as simvastatin and atorvastatin or a solvent weekly for 6 weeks. Retina sections underwent hematoxylin and eosin, Brn3a, or cleaved casepase-3 staining to evaluate RGC survival. In addition, modulation of glial activation was assessed. While the retinas without statin treatment exhibited increased RGC death due to chronic OHT, statins promoted the survival of RGCs and reduced apoptosis. Statins also suppressed chronic OHT-mediated glial activation in the retina. Our results demonstrate that statins exert neuroprotective effects in rat retinas exposed to chronic OHT, which may support the prospect of statins being a glaucoma treatment.  相似文献   
682.
The flame spray method for preparing spherical powders is a technique in which solid particles are forced to fuse into spheres by exposing them directly to the combustion flame, and has already been applied to producing ceramic (metal) spherical powders. With this technique, it is critical to analyze quantitatively the fusing and sphering characteristics of solid particles, and thus the distributions of gas velocity and temperature of the flame gas have to be calculated first. However, little research has been conducted regarding this subject. In this study, a combustion model is formulated to calculate the profiles of gas velocity and temperature for the fuel gas flame jetted from the commonly used coaxial double-pipe nozzle. The calculation agrees roughly with the flame shape observed in experiments, implying the possibility of using this model to calculate the heat transfer from flame gas to solid powders. © 1997 Scripta Technica, Inc. Heat Trans Jpn Res 25(4): 201–213, 1996  相似文献   
683.
Although stimulator of interferon genes (STING) agonists has shown great promise in preclinical studies, the clinical development of STING agonist therapy is challenged by its limited systemic delivery. Here, positively charged fusogenic liposomes loaded with a STING agonist (PoSTING) are designed for systemic delivery and to preferentially target the tumor microenvironment. When PoSTING is administered intravenously, it selectively targets not only tumor cells but also immune and tumor endothelial cells (ECs). In particular, delivery of STING agonists to tumor ECs normalizes abnormal tumor vasculatures, induces intratumoral STING activation, and elicits robust anti-tumor T cell immunity within the tumor microenvironment. Therefore, PoSTING can be used as a systemic delivery platform to overcome the limitations of using STING agonists in clinical trials.  相似文献   
684.
In this study, nanocrystals of antiferromagnetic Cr2O3 are shown via Raman spectroscopy to display peculiar lattice dynamics in terms of phonon softening and the occurrence of an exceptionally strong spin-phonon coupling. This effect, which is observed to persist well above the onset of the antiferromagnetic ordering temperature, is ascribed to locally correlated spin fluctuations due to the modulation of the magnetic exchange interactions as the chromium atoms oscillate about their equilibrium position. It is found that the spin-phonon coupling strength is governed by the competing antiferromagnetic and ferromagnetic interactions, where changes in the surface spin configuration can also play a crucial role. Overall, this work proves the size dependence of the interplay between the crystalline and magnetic structures in 3D antiferromagnets varying the surface-to-volume ratio and helps establish the fundamentals for a spin-phonon coupling engineering at the nanoscale via a simple route in a very stable and easy to synthesize material. More importantly, it demonstrates the possibility of coupling phononic excitations with the magnetization dynamics at room temperature, offering a highly prospective nanomaterial for the design of novel magnonic devices.  相似文献   
685.
686.
Although many medical microrobots have been developed for treating diseases, their designs have not been optimized for disease environments and their functionality and capabilities have been primarily demonstrated in vitro. In addition, the imaging of microrobots within blood vessels in deep tissues remains a challenge. Herein, a chitosan-based biodegradable microrobot with optimized structural design and X-ray imaging for targeted vessel chemoembolization is reported. The design of the microrobot takes into account its magnetizability and stackability in blood vessels. The microrobot is prepared through laser micromachining of a porous chitosan sheet, attachment of nanoparticles, and filling the pores with gelatin. The optimized microrobot is biocompatible, biodegradable, thrombogenic, magnetically targetable, and drug-loadable, as demonstrated both in vitro and in a blood vessel phantom. X-ray imaging of the gold nanoparticle-attached microrobots compares well with using commercial iodinated contrast materials, thereby demonstrating their real-time long-term X-ray imaging capability. The in vivo real-time imaging and targeted vessel embolization of the microrobot are demonstrated in rat liver. The proposed microrobot overcomes the limitations of embolic microbeads currently used in targeted vessel chemoembolization (i.e., targeted vessel blocking and X-ray visibility) and expands the capability of microrobots in advanced platforms for treating human diseases.  相似文献   
687.
Food Science and Biotechnology - Grains contain bioactive components that potentially have protective effects on chronic diseases such as diabetes. The anti-diabetic effects of blended grain...  相似文献   
688.
Food Science and Biotechnology - Sorghum is a vital cereal source that has various phenolic compounds and potential health-promoting benefits. This study evaluated the phenolic content, antioxidant...  相似文献   
689.
Food Science and Biotechnology - The effects on the quality of loin ham from using wet-aging with a commercial refrigerator (CR) and with a pulsed electric field system refrigerator (PEFR, at 0...  相似文献   
690.
Food Science and Biotechnology - Commercial whey protein (CWP) is generally produced in the cheese making process with heat treatment. Recently, native whey protein (NWP) can be obtained through...  相似文献   
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