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991.
Yuqin Shen Yin Liu Han Gao Hongbo Fei Wenwen Yu Tianqi Hu Yi Zheng Xueting Bi Chongtao Lin 《RSC advances》2018,8(15):8080
Oral bone defects are difficult to treat. Recently, endogenous miR-34a was shown to be involved in bone anabolism. Clinical application of such microRNAs requires the inherent instability of microRNAs to be overcome by an efficient delivery system. In this study, we employed N-acetyl-l-leucine-modified polyethylenimine (N-Ac-l-Leu-PEI) as an miR-34a carrier and evaluated its delivery ability, transfection efficiency, cytotoxicity and whether it enhanced osteogenic differentiation and bone formation in vitro and in vivo. Stable N-Ac-l-Leu-PEI/miR-34a nanocomplexes were synthesized at a mass ratio of 4 and had a small size (190.34 nm), a low zeta potential (21.1 mV), a high transfection efficiency (69.39%) and no cytotoxicity in MG63 cells. N-Ac-l-Leu-PEI-mediated miR-34a delivery in vitro promoted ALP activity and expression of osteogenic differentiation markers, Runx2, SP7 and ColI to higher levels than those produced by Lipofectamine 2000-mediated delivery. N-Ac-l-Leu-PEI also achieved delivery of miR-34a in vivo to a local cranial bone defect area with miR-34a retaining the ability to initiate significant new bone formation 12 weeks post-implantation. This demonstrates the potential for N-Ac-l-Leu-PEI as a gene therapy vehicle for the regeneration of bone defects.We employ N-acetyl-l-leucine-modified polyethylenimine as an miR-34a carrier and evaluate its delivery ability, transfection efficiency, cytotoxicity and whether it enhances osteogenic differentiation and bone formation in vitro and in vivo. 相似文献
992.
Wei Han Zhuyao Li Mei Li Yinyi Gao Xiaoguang Yang Milin Zhang Yang Sun 《RSC advances》2018,8(15):8118
The electrochemical reduction of dysprosium(iii) was studied on W and Cu electrodes in eutectic LiCl–KCl by transient electrochemical methods. Cyclic voltammogram and current reversal chronopotentiogram results demonstrated that dysprosium(iii) was directly reduced to dysprosium (0) on the W electrode through a single-step process with the transfer of three electrons. Electrochemical measurements on the Cu electrode showed that different Cu–Dy intermetallics are formed. Moreover, the thermodynamic properties of Cu–Dy intermetallic compounds were estimated by open circuit chronopotentiometry in a temperature range of 773–863 K. Using the linear polarization method, the exchange current density (j0) of dysprosium in eutectic LiCl–KCl on the Cu electrode was estimated, and the temperature dependence of j0 was studied to estimate the activation energies associated with Dy(iii)/Cu5Dy and Dy(iii)/Cu9/2Dy couples. In addition, potentiostatic electrolysis was conducted to extract dysprosium on the Cu electrode, and five Cu–Dy intermetallic compounds, CuDy, Cu2Dy, Cu9/2Dy, Cu5Dy and Cu0.99Dy0.01 were identified by X-ray diffraction, scanning electron microscopy and energy dispersive spectrometry. Meanwhile, the change of dysprosium(iii) concentration was monitored using inductively coupled plasma-atomic emission spectrometry, and the maximum extraction efficiency of dysprosium was found to reach 99.2%.The electrochemical reduction of dysprosium(iii) was studied on W and Cu electrodes in eutectic LiCl–KCl by transient electrochemical methods. 相似文献
993.
The standard method for methanol assay in wine is based on a methanol/KMnO4/H2C2O4/fuchsin sodium sulfite (FSS) reaction system. However, it is difficult to control the degree of colour and the temperature of the reaction product in this assay, and its repeatability is also poor due to the generation of CO and CO2 in the reaction. Therefore, to solve these problems, potassium metabisulfite was selected to replace H2C2O4, and an automatic analysis method was developed which can realize rapid and accurate determination of methanol and can be used to make an online analyzer. It was discovered that the reactions of methanol/KMnO4 and acetaldehyde/FSS are exothermic, while the reactions of methanol/KMnO4 and formaldehyde/FSS are endothermic. Consequently, based on the temperature effect, not only was the interference of ethanol eliminated in detecting methanol in wines, the purpose of the research was achieved to directly and accurately determine methanol without sample pretreatment. By optimizing the system, the obtained conditions for determining methanol in wines were as follows: 20 g L−1 concentration for KMnO4; 3 g L−1 concentration for FSS; 40 cm length for the first reaction coil (RC1); 100 cm length for RC2; 700 cm (I.D.: 0.8 mm) length for RC3; 50 °C for RC3; about 20 °C for RC1 and RC2; 330 μL for the sample volume. The method showed a linear response in the range 25–1000 mg L−1, with a 0.6% RSD, 8.8 mg L−1 detection limit and 25 samples per h, and was successfully used for testing representative wine samples. It also obtained better accuracy than previous methods. Due to its superiority in automated operation, reproducibility, analysis speed and test cost, this method and system can serve as a supplementary standard for methanol assay, and for the quality control of the winemaking process and the final wine-product, as well as for low-alcohol drinks.We found that methanol/KMnO4 and acetaldehyde/FSS are exothermic, formaldehyde/FSS is endothermic, so based on the temperature effect, eliminated ethanol interference in detecting methanol in wines, also realized automatic analysis for methanol without sample pretreatment. 相似文献
994.
Jia Jia Hongmei Yu Xueqiang Gao Jun Chi Yachao Zeng Bowen Qin Dewei Yao Wei Song Zhigang Shao Baolian Yi 《RSC advances》2018,8(23):12887
A novel cathode architecture using vertically aligned Co nanoneedle arrays as an ordered support for application in alkaline anion-exchange membrane fuel cells (AAEMFCs) has been developed. The Co nanoneedle arrays were directly grown on a stainless steel sheet via a hydrothermal reaction and then a Pd layer was deposited on the surface of the Co nanoneedle arrays using a vacuum sputter-deposition method to form Pd/Co nanoneedle arrays. After transferring the Pd/Co nanoneedle arrays to an AAEM, a cathode catalyst layer was formed. Without the use of an alkaline ionomer, the AAEMFC with the prepared cathode catalyst layer showed an enhanced performance with ultra-low Pd loading of down to 33.5 μg cm−2, which is much higher than the conventionally used cathode electrode with a Pt loading of 100 μg cm−2. This is the first report where three-dimensional Co nanoneedle arrays have been used as the cathode support in an AAEMFC, which is able to deliver a higher power density without an alkaline ionomer than that of conventional membrane electrode assembly (MEA).A novel ordered Pd/Co nanoneedle array was used as a cathode in an AAEMFC and delivered a higher power density than that of conventional MEA. 相似文献
995.
Gayatri Shankar Chilambi Iris H. Gao Bo Kyeong Yoon Soohyun Park Lisa M. Kawakami Vikashini Ravikumar Mary B. Chan-Park Nam-Joon Cho Guillermo C. Bazan Kimberly A. Kline Scott A. Rice Jamie Hinks 《RSC advances》2018,8(19):10284
The growing problem of antibiotic resistant bacteria, along with a dearth of new antibiotics, has redirected attention to the search for alternative antimicrobial agents. Conjugated oligoelectrolytes (COEs) are an emerging class of antimicrobial agents which insert into bacterial cell membranes and are inhibitory against a range of Gram-positive and Gram-negative bacteria. In this study, the extent of COE resistance that Enterococcus faecalis could achieve was studied. Enterococci are able to grow in hostile environments and develop resistance to membrane targeting antibiotics such as daptomycin in clinical settings. Herein we expand our knowledge of the antimicrobial mechanism of action of COEs by developing COE-resistant strains of E. faecalis OG1RF. Evolution studies yielded strains with a moderate 4–16 fold increase in antimicrobial resistance relative to the wild type. The resistant isolates accumulated agent-specific mutations associated with the liaFSR operon, which is a cell envelope-associated stress-response sensing and regulating system. The COE resistant isolates displayed significantly altered membrane fatty acid composition. Subsequent, exogenous supplementation with single fatty acids, which were chosen based on those dominating the fatty acid profiles of the mutants, increased resistance of the wild-type E. faecalis to COEs. In combination, genetic, fatty acid, and uptake studies support the hypothesis that COEs function through insertion into and disruption of membranes and that the mechanism by which this occurs is specific to the disrupting agent. These results were validated by a series of biophysical experiments showing the tendency of COEs to accumulate in and perturb adapted membrane extracts. Collectively, the data support that COEs are promising antimicrobial agents for targeting E. faecalis, and that there is a high barrier to the emergence of severely resistant strains constrained by biological limits of membrane remodeling that can occur in E. faecalis.COEs are emerging antimicrobials to combat drug resistant infections and to which bacteria develop only limited resistance. 相似文献
996.
Hong Zhou Zhuo Qu Jingze Zhang Bingjie Jiang Changxiao Liu Wenyuan Gao 《RSC advances》2018,8(19):10163
The Shunaoxin dropping pill (SNX) is derived from a traditional recipe. It has been used to treat cerebrovascular diseases in China since 2005 (approval number Z20050041). In this study, we used an in vitro H2O2-induced PC12 cell oxidative damage model and an in vivod-gal-induced mouse memory impairment model to investigate whether SNX had neuroprotective effects. In vitro, prior to exposure to 100 μM H2O2 for 2 h, PC12 cells were pre-treated with SNX 50 μg mL−1 for 24 h. Hoechst 33258 staining was used to confirm the effect of SNX on apoptosis in the PC12 cells. Our results demonstrate that H2O2 suppresses the proliferation of PC12 cells and induces cell death. Pretreatment with SNX attenuates H2O2-induced apoptosis in PC12 cells. In vivo, d-gal was administered (100 mg kg−1, subcutaneously (s.c.)) once daily for 8 weeks to induce memory deficit and neurotoxicity in the brain of an aging mouse. Then, SNX (320 mg kg−1) was simultaneously administered orally. The present study demonstrates that SNX can alleviate aging in the mouse brain induced by d-gal via improving behavioral performance, alleviating oxidative stress, inhibiting neuroinflammation, and reducing brain cell damage in the hippocampus. Overall, these data clearly demonstrate the neuroprotective effect of SNX from the in vitro and in vivo results. SNX may be considered a novel agent for easing aging and/or age-related neurodegenerative diseases.The Shunaoxin dropping pill (SNX) is derived from a traditional recipe. 相似文献
997.
In recent years, perovskite solar cells (PSCs) have attracted great attention in the photovoltaic research field, because of their high-efficiency (certified 22.1%) and low-cost. In this review paper, we briefly introduce the history of efficiency development for PSCs, and discuss some of the major problems for large-area (≥1 cm2) PSC devices. In addition, we summarize the recent progress in the aspects of fabrication methods for large-area perovskite films, and improving the efficiency and stability of the large-area PSC devices. Finally, we give a short summary and outlook of large-area PSC devices. This article is mainly organized into three parts. The first part focuses on the main fabricating technologies for large-area perovskite films. The second section discusses some methods that are used to improve the efficiency of PSCs. In the last part, different approaches are used to improve the stability of PSCs.In this review, we summarize the recent progress in the aspects of the fabrication methods for large-area perovskite films, improving the efficiency and stability of the large-area PSC devices. 相似文献
998.
Local application of lactoferrin promotes bone regeneration in a rat critical‐sized calvarial defect model as demonstrated by micro‐CT and histological analysis 下载免费PDF全文
Ryan Gao Maureen Watson Karen E. Callon Donna Tuari Michael Dray Dorit Naot Satya Amirapu Jacob T. Munro Jillian Cornish David S. Musson 《Journal of tissue engineering and regenerative medicine》2018,12(1):e620-e626
Lactoferrin is a multifunctional glycoprotein with therapeutic potential for bone tissue engineering. The aim of this study was to assess the efficacy of local application of lactoferrin on bone regeneration. Five‐millimetre critical‐sized defects were created over the right parietal bone in 64 Sprague–Dawley rats. The rats were randomized into four groups: group 1 (n = 20) had empty defects; group 2 (n = 20) had defects grafted with collagen gels (3 mg/ml); group 3 (n = 20) had defects grafted with collagen gels impregnated with bovine lactoferrin (10 μg/gel); and group 4 (n = 4) had sham surgeries (skin and periosteal incisions only). The rats were sacrificed at 4 or 12 weeks post‐operatively, and the calvaria were excised and evaluated with micro‐CT (Skyscan 1172) followed by histology. The bone volume fraction (BV/TV) was higher in lactoferrin‐treated animals at both timepoints, with groups 1, 2, 3 and 4 measuring 10.5 ± 1.1%, 8.6 ± 1.4%, 16.5 ± 0.6% and 24.27 ± 2.6%, respectively, at 4 weeks (P < 0.05); and 12.2 ± 1.3%, 13.6 ± 1.5%, 21.9 ± 1.2% and 29.3 ± 0.8%, respectively, at 12 weeks (P < 0.05). Histological analysis revealed that the newly formed bone within the calvarial defects of all groups was a mixture of woven and lamellar bone, with more bone in the group treated with lactoferrin at both timepoints. Our study demonstrated that local application of lactoferrin significantly increased bone regeneration in a rat critical‐sized calvarial defect model. The profound effect of lactoferrin on bone regeneration has therapeutic potential to improve the poor clinical outcomes associated with bony non‐union. LF In Vivo JTERM Authors Contributions. Copyright © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons, Ltd. 相似文献
999.
Mingxing Zhao Wei Gao Long Zhang Wei Huang Sihua Zheng Guanliang Wang Brian Y. Hong Baoyong Tang 《PM & R》2018,10(1):36-44
Background
Ankle sprains occur frequently among young and active people, accounting for almost 2 million injuries per year. Previous reports suggest that acupressure therapy for acute ankle sprains may shorten the recovery time.Objective
To evaluate whether acupressure therapy can improve ankle sprain recovery compared with standard RICE (rest, ice, compression, and elevation) treatment.Design
A randomized controlled trial was conducted. The study protocol was registered in the Chinese Clinical Trial Registry with the study registration number: ChiCTR-TRC-14004794.Setting
Department of Traditional Chinese Medicine Orthopedics, PLA No.60 Center Hospital, Dali, China, and Department of Orthopedics, Xixi Hospital of Hangzhou, Hangzhou China, between June 2014 and January 2016.Patients
A total of 68 patients with acute ankle sprains were assessed for study eligibility, and a total of 62 patients were included in the present study.Methods
All patients with ankle sprains seen by the Orthopedics Department within 48 hours since the time of injury were identified. Consenting patients were randomized to either (1) standard treatment (ST group), (2) standard treatment + acupressure (AP group), or (3) standard treatment + mock acupressure (mock AP group).Main Outcome Measurements
Outcomes of interest included a volumetric measurement of the foot, ankle, and lower leg), range of ankle movement, and visual analog pain scores. The American Orthopedic Foot and Ankle Score) and SF12v2 scores were used to assess quality of life.Results
Among the 62 randomized patients, the mean (95% confidence interval [CI]) volumetric measurement of the foot, ankle, and lower leg in the AP group decreased from 185.24 (95% CI 142.80-227.67) to 62.14 (95% CI 44.03-80.25) after 3 sessions of acupressure treatment. This was a statistically significant difference (P < .01) compared with the means of ST group (119.00; 95% CI 89.14-148.86) and mock AP group (118.18; 95% CI 83.99-152.37). After the first treatment, the mean range of ankle movement, visual analog pain scores, and American Orthopedic Foot and Ankle Scores of the AP group were 31.67 (95% CI 27.78-35.55), 3.33 (95% CI 2.97-3.70), and 55.86 (95% CI 50.03-61.69), respectively. These scores were statistically better (P < .01) than the mean of the ST and mock AP group scores. In addition, the mean SF12v2 scores of AP group at 4 and 8 weeks were 109.95 (95% CI 107.29-112.62) and 119.67 (95% CI 119.27-120.05), respectively. These scores were also significantly greater than those of the ST group and mock AP groups (P < .01).Conclusion
Acupressure therapy may improve recovery after acute ankle sprain injury, yielding shortened time of disability and improved quality of life.Level of Evidence
I 相似文献1000.
The effects of acidic treatment, cellulase hydrolysis, particle size distribution and pH on the adsorption capacity of defatted coconut cake dietary fibers (DCCDF) were studied. The results demonstrated that cellulase hydrolysis could significantly improve the soluble dietary fiber content, water holding ability and adsorption ability of DCCDF on cholesterol, bile and nitrite ions. Acidic treatment enhanced the oil holding capacity and adsorption ability in cholesterol and nitrite ions. Moreover, the adsorption ability of DFs in cholesterol, nitrite and bile all increased with reduced particle size (250 to 167 μm), and DCCDF demonstrated a higher adsorption capacity at pH 2.0 than at pH 7.0. The change in adsorption capacity of DCCDF might be suitable for application in the food industry as a low-calorie and cholesterol lowering functional ingredient.This paper provides valuable information on the effects of cellulase hydrolysis, acidic treatment, particle size distribution and pH on the adsorption activity of coconut cake dietary fibers. 相似文献