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101.
X. F. Zhang B. Wang J. Yu X.
N. Wu Y. H. Zang H. C. Gao P. C. Su S. Q. Hao 《RSC advances》2018,8(3):1159
In this study, porous carbon (3DHPC) with a 3D honeycomb-like structure was synthesized from waste biomass corncob via hydrothermal carbonization coupled with KOH activation and investigated as a capacitive deionization (CDI) electrode material. The obtained 3DHPC possesses a hierarchal macroporous and mesoporous structure, and a large accessible specific surface area (952 m2 g−1). Electrochemical tests showed that the 3DHPC electrode exhibited a specific capacitance of 452 F g−1 and good electric conductivity. Moreover, the feasibility of electrosorptive removal of chromium(vi) from an aqueous solution using the 3DHPC electrode was demonstrated. When 1.0 V was applied to a solution containing 30 mg L−1 chromium(vi), the 3DHPC electrode exhibited a higher removal efficiency of 91.58% compared with that in the open circuit condition. This enhanced adsorption results from the improved affinity between chromium(vi) and the electrode under electrochemical assistance involving a non-faradic process. Consequently, the 3DHPC electrode with typical double-layer capacitor behavior is demonstrated to be a favorable electrode material for capacitive deionization.A porous carbon electrode with a 3D honeycomb-like structure demonstrates a high removal efficiency for the removal of chromium(vi) from water. 相似文献
102.
Dong Wang Lichun An Jiangke Tian Tengfei Yu Xia Xie Yuejuan Gao Yanfen Zang Yanyan Tao Yanqing Liu Ying Jin 《The American journal of emergency medicine》2018,36(9):1627-1630
Background
Real-time ultrasound elastography (RTE) is used to examine liver fibrosis and benign and malignant lesions, but its use for the diagnosis of liver trauma has not been examined. The purpose of this study was to examine the use of RTE for the evaluation of differential penetrating liver trauma in a rabbit model.Material and methods
Eighty New Zealand rabbits were divided into 2 groups. In one group, a single incision (type “-” lesion) was made, and in the other group a hash mark incision (type “#” lesion) was made (about 0.5 cm in depth; 1.0–2.0 cm in length). RTE was performed at 10, 30, and 60 min after injury.Results
There were no differences in mean RTE scores between the 2 types of lesions at 10 and 30 min. However, the mean values for the 2 types of lesions increased from 10 min to 60 min (type ‘-’ lesion: 0.88 ± 0.32 to 2.06 ± 0.88; type ‘#’ lesion: 0.89 ± 0.34 to 2.63 ± 1.16). At 60 min, the mean elasticity score in the type ‘#’ lesion group was significantly higher than in the type ‘-’ lesion group (P < .001). Strain ratios were not different between the groups at each time point, but in each group the values decreased from the 10 min time point to the 60 min time point (P-value for the trends, <.001).Conclusions
RTE may be able to distinguish mild or severe penetrating liver trauma at 60 min or more after injury. 相似文献103.
Xing‐Zhu Lu Xue‐Yuan Bi Xi He Ming Zhao Man Xu Xiao‐Jiang Yu Zheng‐Hang Zhao Wei‐Jin Zang 《British journal of pharmacology》2015,172(23):5619-5633
Background and Purpose
The activation of M 3 cholinoceptors (M 3 receptors) by choline reduces cardiovascular risk, but it is unclear whether these receptors can regulate ischaemia/reperfusion (I/R)‐induced vascular injury. Thus, the primary goal of the present study was to explore the effects of choline on the function of mesenteric arteries following I/R, with a major focus on Ca2+/calmodulin‐dependent protein kinase II (CaMKII) regulation.Experimental Approach
Rats were given choline (10 mg·kg−1, i.v.) and then the superior mesenteric artery was occluded for 60 min (ischaemia), followed by 90 min of reperfusion. The M 3 receptor antagonist, 4‐diphenylacetoxy‐N‐methylpiperidine methiodide (4‐DAMP), was injected (0.12 μg·kg−1, i.v.) 5 min prior to choline treatment. Vascular function was examined in rings of mesenteric arteries isolated after the reperfusion procedure. Vascular superoxide anion production, CaMKII and the levels of Ca2+‐cycling proteins were also assessed.Key Results
Choline treatment attenuated I/R‐induced vascular dysfunction, blocked elevations in the levels of reactive oxygen species (ROS) and decreased the up‐regulated expression of oxidised CaMKII and phosphorylated CaMKII. In addition, choline reversed the abnormal expression of Ca2+‐cycling proteins, including Na+/Ca2+ exchanger, inositol 1,4,5‐trisphosphate receptor, sarcoplasmic reticulum Ca2+‐ATPase and phospholamban. All of these cholinergic effects of choline were abolished by 4‐DAMP.Conclusions and Implications
Our data suggest that inhibition of the ROS‐mediated CaMKII pathway and modulation of Ca2+‐cycling proteins may be novel mechanisms underlying choline‐induced vascular protection. These results represent a significant addition to the understanding of the pharmacological roles of M 3 receptors in the vasculature, providing a new therapeutic strategy for I/R‐induced vascular injury.Linked Articles
This article is part of a themed section on Chinese Innovation in Cardiovascular Drug Discovery. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-23Abbreviations
- 4‐DAMP
- 4‐diphenylacetoxy‐N‐methylpiperidine methiodide
- CaMKII
- Ca2+/calmodulin‐dependent protein kinase II
- DHE
- dihydroethidium
- I/R
- ischaemia/reperfusion
- IP3R
- inositol 1,4,5‐trisphosphate receptor
- NAC
- N‐acetyl‐L‐cysteine
- NCX
- Na+/Ca2+ exchanger
- PLB
- phospholamban
- ROS
- reactive oxygen species
- SERCA
- sarcoplasmic reticulum Ca2+‐ATPase
- SNP
- sodium nitroprusside
TARGETS |
---|
GPCRs a |
M3 receptors |
Enzymes b |
SERCA 2, sarcoplasmic reticulum Ca2+‐ATPase |
Ion channels c |
NCX1, Na+/Ca2+ exchanger |
Ligand‐gated ion channels d |
IP3R, inositol 1,4,5‐trisphosphate receptor |
LIGANDS |
---|
4‐DAMP, 4‐diphenylacetoxy‐N‐methylpiperidine methiodide |
5‐HT |
ACh |
Caffeine |
Choline |
Darifenacin |
KN‐93 |
L‐NAME, NG‐nitro‐L‐arginine methyl ester |
Phenylephrine |
104.
Shuai Zhao Shicheng Xie Peipei Sun Zheng Zhao Lin Li Xiaoming Shao Xiaolin Liu Zhenxiang Xin 《RSC advances》2018,8(32):17813
A novel graphene–silicon dioxide hybrid (HGS) was prepared by plant polyphenol-tannic acid (TA) functionalized pristine graphene (G-TA) and primary amine-containing silane coupling agent modified SiO2 (Si–NH2). Through strong hydrogen-bonding interaction between the phenolic hydroxyl groups on G-TA and primary amine groups on Si–NH2, SiO2 was uniformly loaded to the surface of graphene. Due to the synergistic dispersion effect of graphene and SiO2, which prevents restacking and re-aggregating of both graphene and SiO2, HGS hybrids were distributed evenly in the natural rubber (NR) matrix (HGS@NR). Simultaneously, the surface roughness of graphene after loading SiO2 and the interfacial interaction between the HGS hybrid and NR matrix were substantially improved. Due to the good dispersion and strong interface, the overall properties of HGS@NR nanocomposites are drastically enhanced compared with those of GS@NR nanocomposites prepared by dispersing the blend of unmodified graphene and SiO2 (GS) in NR. The HGS@NR nanocomposites possess the highest tensile strength up to 27.8 MPa at 0.5 wt% and tear strength of 60.2 MPa at 0.5 wt%. Thermal conductivities of the HGS@NR nanocomposites were found to be 1.5-fold better than that of the GS@NR nanocomposites. Also, the HGS@NR nanocomposites exhibit excellent abrasive resistant capacity that is nearly 2-fold better than that of the GS@NR nanocomposites. These results suggest that HGS has great potential in high-performance nanocomposites and a new strategy of constructing the efficient graphene–SiO2 hybrid fillers has been established.A novel graphene–silicon dioxide hybrid (HGS) was prepared by plant polyphenol-tannic acid (TA) functionalized pristine graphene (G-TA) and primary amine-containing silane coupling agent modified SiO2 (Si–NH2). 相似文献
105.
James Reigle Dina Secic Jacek Biesiada Collin Wetzel Behrouz Shamsaei Johnson Chu Yuanwei Zang Xiang Zhang Nicholas J. Talbot Megan E. Bischoff Yongzhen Zhang Charuhas V. Thakar Krishnanath Gaitonde Abhinav Sidana Hai Bui John T. Cunningham Qing Zhang Laura S. Schmidt W. Marston Linehan Mario Medvedovic David R. Plas Julio A. Landero Figueroa Jarek Meller Maria F. Czyzyk-Krzeska 《The Journal of clinical investigation》2021,131(1)
106.
107.
Paclitaxel-induced stress granules increase LINE-1 mRNA stability to promote drug resistance in breast cancer cells 下载免费PDF全文
Xiao Shi Xinxin Si Ershao Zhang Ruochen Zang Nan Yang He Cheng Zhihong Zhang Beijing Pan Yujie Sun 《生物医学研究杂志》2021,35(6):411-424
Abnormal expression of long interspersed element-1 (LINE-1) has been implicated in drug resistance, while our previous study showed that chemotherapy drug paclitaxel (PTX) increased LINE-1 level with unknown mechanism. Bioinformatics analysis suggested the regulation of LINE-1 mRNA by drug-induced stress granules (SGs). This study aimed to explore whether and how SGs are involved in drug-induced LINE-1 increase and thereby promotes drug resistance of triple negative breast cancer (TNBC) cells. We demonstrated that SGs increased LINE-1 expression by recruiting and stabilizing LINE-1 mRNA under drug stress, thereby adapting TNBC cells to chemotherapy drugs. Moreover, LINE-1 inhibitor efavirenz (EFV) could inhibit drug-induced SG to destabilize LINE-1. Our study provides the first evidence of the regulation of LINE-1 by SGs that could be an important survival mechanism for cancer cells exposed to chemotherapy drugs. The findings provide a useful clue for developing new chemotherapeutic strategies against TNBCs. 相似文献
108.
目的通过有限元方法比较不同全瓷材料和厚度在种植牙冠修复的应力分布情况,为临床冠部修复材料的选择和设计提供参考。方法建立下颌第一磨牙种植牙冠修复有限元模型,并进行6种冠厚度和4种不同冠修复材料,即树脂基陶瓷(Lava Ultimate和Vita Enamic)、二硅酸锂玻璃陶瓷(IPS e.max CAD)和氧化锆陶瓷(Cercon)进行组合。在下颌第一磨牙面加载600 N,使用有限元软件ANSYS 10.0分析应力分布。结果冠部应力分析显示,4 mm?Cercon组156.05 MPa最高,1 mm?Lava Ultimate组18.85 MPa最低。树脂水门汀应力分析显示,4 mm?Lava Ultimate组62.52 MPa最高,1 mm?IPS e.max CAD组16.74 MPa最低。使用成品基台时,Lava Ultimate组在冠修复体、树脂水门汀中的应力集中较相同冠厚度的个性化基台高。结论随着冠厚度增加,冠修复体和树脂水门汀中的最大主应力集中呈现上升趋势;树脂基陶瓷使用个性化基台更有利于减少应力集中。 相似文献
109.
Hongquan Wei Yong Zhang Lei Shi Jingru Zhang Yan Xia Jian Zang Aihui Yan Wei Li Xuejun Jiang 《International journal of medical sciences》2013,10(13):1914-1920
Objectives: This study was to compare the efficacies and side effects of high intensity focused ultrasound (HIFU) treatment for perennial allergic rhinitis (PAR) with regular and increased dosage.Study design: A prospectively assembled cohort was retrospectively analyzed through visual analogue scale (VAS).Methods: Regular dosage of HIFU treatment was applied to 56 PAR patients in group A. An increased dosage as twice as the regular one was applied to 48 patients in group B. Nasal obstruction, sneezing, rhinorrhea and rhinocnesmus, which were recognized as the four main symptoms of allergic rhinitis (AR), were evaluated before treatment, 3 months after treatment, and 1 year after treatment. The satisfaction of patients was also evaluated at 1 year postoperatively. Biopsy of the inferior turbinate and morphometric analysis were applied to 11 patients in group A and 10 in group B before HIFU treatment and 3 months after treatment.Results: Comparing the AR symptoms before treatment, There is no statistical difference observed between group A and B (p>0.05). The four main symptoms at 3 months and 1 year after treatment were all significantly improved (p<0.01) in both group A and B. The VAS scores of AR symptoms in Group B were lower than those in Group A at the same stage after treatment, especially at 1 year after treatment (p<0.05). Comparing the results at 3 months and 1 year after treatment, a tendency of recurrence of these symptoms was observed statistically in group A (p<0.05), but not in group B (p>0.05). More cases of nasal dryness and perirhinal swelling were found in group B than those in group A (p<0.05), while all side effects were mild and temporary. Patients in group B were more satisfied than those in group A (p=0.0866 >0.05), though not statistically significant. More reduction of the eosinophils, other inflammatory cells, and the submucosal glands was observed after HIFU treatment in group B than that in group A (p<0.05).Conclusions: A proper increment of HIFU dosage may be recommended to meet the needs of more improvement of AR symptoms and less recurrence. 相似文献
110.
A multiple core–shell heterostructure Rh–Rh3+ modified Ta2O5@TaON@Ta3N5 nanophotocatalyst was successfully constructed through nitriding Rh3+-doped Ta2O5 nanoparticles, which exhibited a much higher carrier separation efficiency about one order of magnitude higher than the Ta2O5@Ta3N5 precursor, and thus an excellent visible light photocatalytic H2-evolution activity (83.64 μmol g−1 h−1), much superior to that of Rh anchored Ta2O5@TaON (39.41 μmol g−1 h−1), and improved stability due to the residual Rh–O/N in the Ta3N5 shell layer. Rh-modifying significantly extended light absorption to the overall visible region. Localized built-in electric fields with hierarchical potential gradients at the multiple interfaces including a Rh/Ta3N5 Schottky junction and double n–n Ta3N5/TaON/Ta2O5 mutant heterojunctions, drove charge carriers to directionally transfer from inside to outside, and efficiently separate. Enhanced photoactivity was ascribed to a synergetic effect of improved light absorption ability, increased carrier separation efficiency, and accelerated surface reaction. A promising strategy of developing excellent Ta3N5-based photocatalysts for solar energy conversion is provided by constructing double n–n mutant heterojunctions.Localized built-in electric fields at multiple hierarchical interfaces facilitate the efficient separation and fast inside-out directional transfer of photogenerated carriers. 相似文献