RNA folds into intricate structures that are crucial for its functions and regulations. To date, a multitude of approaches for probing structures of the whole transcriptome, i.e., RNA struc-turomes, have been developed. Applications of these approaches to different cell lines and tissues have generated a rich resource for the study of RNA structure–function relationships at a systems biology level. In this review, we first introduce the designs of these methods and their applications to study different RNA structuromes. We emphasize their technological differences especially their unique advantages and caveats. We then summarize the structural insights in RNA functions and regulations obtained from the studies of RNA structuromes. And finally, we propose potential directions for future improvements and studies.

BACKGROUND: Alendronate (AL), a drug for inhibiting osteoclast-mediated bone-resorption, was intercalated into an inorganic drug delivery nanovehicle, layered double hydroxide (LDH), to form a new nanohybrid, AL-LDH, with 1:1 heterostructure along the crystallographic C-axis. Based on the intercalation reaction strategy, the present AL-LDH drug delivery system (DDS) was realized with an enhanced drug efficacy of AL, which was confirmed by the improved proliferation and osteogenic differentiation of osteoblast-like cells (MG63). METHODS: The AL-LDH nanohybrid was synthesized by conventional ion-exchange reaction and characterized by powder X-ray diffraction (PXRD), high-resolution transmission electron microscopy (HR-TEM), and Fourier transform infrared (FT-IR) spectroscopy. Additionally, in vitro efficacy tests, such as cell proliferation and alkaline phosphatase (ALP) activity, were analyzed. RESULTS: The AL was successfully intercalated into LDH via ion-exchange reaction, and thus prepared AL-LDH DDS was X-ray single phasic and chemically well defined. The accumulated AL content in MG63 cells treated with the AL-LDH DDS nanoparticles was determined to be 10.6-fold higher than that within those treated with the intact AL after incubation for 1 hour, suggesting that intercellular permeation of AL was facilitated thanks to the hybridization with drug delivery vehicle, LDH. Furthermore, both in vitro proliferation level and ALP activity of MG63 treated with the present hybrid drug, AL-LDH, were found to be much more enhanced than those treated with the intact AL. This is surely due to the fact that LDH could deliver AL drug very efficiently, although LDH itself does not show any effect on proliferation and osteogenic differentiation of MG63 cells. CONCLUSION: The present AL-LDH could be considered as a promising DDS for improving efficacy of AL.
Alendronate ; Alkaline Phosphatase ; Cell Proliferation ; Drug Delivery Systems ; Fourier Analysis ; In Vitro Techniques ; Microscopy, Electron, Transmission ; Nanoparticles ; Spectrum Analysis ; X-Ray Diffraction

Objective:To evaluate the effect of sodium sivelestat on the expression of specialized pro-resolving mediators (SPMs) synthesis enzymes in mice with lipopolysaccharide (LPS)-induced acute lung injury (ALI).Methods:Eighteen SPF healthy male C57BL/6 mice, aged 6-8 weeks, weighing 20-25 g, were divided into 3 groups ( n=6 each) using a random number table method: control group (C group), LPS-induced ALI group (ALI group), and LPS-induced ALI + sodium sivelestat group (ALI+ SV group). ALI was induced by intravenous injection of LPS 15 mg/kg through the tail vein. Sodium sivelestat 50 mg/kg was intraperitoneally injected at 1 h after LPS administration. At 12 h after LPS administration, blood samples were collected from the eyeballs for routine blood tests, and the remaining blood was processed for serum extraction. The mice were sacrificed after anesthesia, and lung tissues were collected to determine the wet/dry weight (W/D) ratio, serum concentrations of interleukin-1beta (IL-1β) and IL-10 (by enzyme-linked immunosorbent assay), expression of neutrophil elastase (NE) and SPMs synthesis enzymes 5-lipoxygenase (5-LOX), 12-lipoxygenase (12-LOX), and 15-lipoxygenase (15-LOX) in lung tissues (by Western blot) and to examine the pathological changes of lung tissues which were scored. Results:Compared with C group, the lung injury scores, W/D ratio, white blood cell counts, percentage of neutrophil, and serum IL-1β and IL-10 concentrations were significantly increased, the expression of NE was up-regulated, and the expression of 5-LOX, 12-LOX and 15-LOX was down-regulated in ALI group ( P<0.05). Compared with ALI group, the lung injury scores, W/D ratio, white blood cell counts, percentage of neutrophil, and serum IL-1β concentration were significantly decreased, the serum IL-10 concentration was increased, the expression of NE was down-regulated, and the expression of 5-LOX, 12-LOX and 15-LOX was up-regulated in ALI+ SV group ( P<0.05). Conclusions:The mechanism by which sodium sivelestat alleviates LPS-induced ALI may be related to up-regulating the expression of SPMs synthesis enzyme and promoting the resolution of pulmonary inflammation in mice.