Chlorogenic acid is a well-known antioxidant and has more isomers according to the difference in binding location and number of caffeic on quinic acid. In this study, we investigated and compared the ...profiles of antioxidant and DNA-protective activities of chlorogenic acid isomers including three caffeoylquinic acid isomers (3-O-caffeoylquinic acid, 3-CQA; 4-O-caffeoylquinic acid, 4-CQA; and 5-O- caffeoylquinic acid, 5-CQA) and three dicaffeoylquinic acid isomers (3,5-dicaffeoyl-quinic acid, ICAA; 3,4-dicaffeoylquinic acid, ICAB; and 4,5-dicaffeoyl-quinic acid, ICAC). The results showed that each of chlorogenic acid isomers studied exhibited antioxidant activities and DNA damage protective effects to various extents. On the whole, dicaffeoylquinic acids possessed better antioxidant activities, mostly because they have more hydroxyl groups than caffeoylquinic acids. Three caffeoylquinic acid isomers showed quite similar antioxidant activities, indicating that the position of esterification on the quinic moiety of caffeoylquinic acid had no effect on its antioxidant activities. Quite the contrary, a difference among dicaffeoylquinic acid isomers was observed, namely, ICAA and ICAB exhibited the same antioxidant activities, whereas ICAC had higher antioxidant activities than ICAA and ICAB in some assays, which implied that their antioxidant activities were probably influenced by the position of esterification on the quinic moiety. We speculated that this difference might be due to the fact that there may exist a steric hindrance effect in the ICAC. However, this assumption needs to be further confirmed.
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IJS, KILJ, NUK, PNG, UL, UM, UPUK
Executing safe brachiation maneuvers with a cable-suspended underactuated robot is a challenging problem due to the complications induced by the cable dynamics. We present and experimentally ...implement an online adaptive controller for a wire-borne brachiating robot swinging on a vibrating cable. An adaptive function approximation approach is proposed to estimate the unknown dynamics of the flexible cable as an external force applied to the robot. Robust control Lyapunov and barrier functions are designed and incorporated into quadratic programs to synthesize a unified adaptive control framework, which formally guarantees the stability and safety of the brachiating robot in the presence of dynamic uncertainties, actuator constraints, and obstacles in the environment. The stability analysis and derivation of the adaptation law are carried out through a Lyapunov analysis. We demonstrate and validate the proposed control framework using extensive hardware experiments with an underactuated brachiating robot operating on a flexible cable. Simulation results, hardware experiments, and comparisons with a baseline controller show that the proposed quadratic programming-based controller achieves reliable tracking performance and disturbance estimation in the presence of model uncertainties, actuator limits, and safety constraints.
Long non-coding RNAs (lncRNAs) are essential factors that regulate tumor development and metastasis via diverse molecular mechanisms in a broad type of cancers. However, the pathological roles of ...lncRNAs in gallbladder carcinoma (GBC) remain largely unknown. Here we discovered a novel lncRNA termed lncRNA Highly expressed in GBC (lncRNA-HGBC) which was upregulated in GBC tissue and aimed to investigate its role and regulatory mechanism in the development and progression of GBC.
The expression level of lncRNA-HGBC in GBC tissue and different cell lines was determined by quantitative real-time PCR. The full length of lncRNA-HGBC was obtained by 5' and 3' rapid amplification of the cDNA ends (RACE). Cellular localization of lncRNA-HGBC was detected by fluorescence in situ hybridization (FISH) assays and subcellular fractionation assay. In vitro and in vivo assays were preformed to explore the biological effects of lncRNA-HGBC in GBC cells. RNA pull-down assay, mass spectrometry, and RNA immunoprecipitation (RIP) assay were used to identify lncRNA-HGBC-interacting proteins. Dual luciferase reporter assays, AGO2-RIP, and MS2-RIP assays were performed to verify the interaction between lncRNA-HGBC and miR-502-3p.
We found that lncRNA-HGBC was upregulated in GBC and its upregulation could predict poor survival. Overexpression or knockdown of lncRNA-HGBC in GBC cell lines resulted in increased or decreased, respectively, cell proliferation and invasion in vitro and in xenografted tumors. LncRNA-HGBC specifically bound to RNA binding protein Hu Antigen R (HuR) that in turn stabilized lncRNA-HGBC. LncRNA-HGBC functioned as a competitive endogenous RNA to bind to miR-502-3p that inhibits target gene SET. Overexpression, knockdown or mutation of lncRNA-HGBC altered the inhibitory effects of miR-502-3p on SET expression and downstream activation of AKT. Clinically, lncRNA-HGBC expression was negatively correlated with miR-502-3p, but positively correlated with SET and HuR in GBC tissue.
Our study demonstrates that lncRNA-HGBC promotes GBC metastasis via activation of the miR-502-3p-SET-AKT cascade, pointing to lncRNA-HGBC as a new prognostic predictor and a therapeutic target.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Dark cosmic rays Hu, Ping-Kai; Kusenko, Alexander; Takhistov, Volodymyr
Physics letters. B,
05/2017, Volume:
768, Issue:
C
Journal Article
Peer reviewed
Open access
If dark matter particles have an electric charge, as in models of millicharged dark matter, such particles should be accelerated in the same astrophysical accelerators that produce ordinary cosmic ...rays, and their spectra should have a predictable rigidity dependence. Depending on the charge, the resulting “dark cosmic rays” can be detected as muon-like or neutrino-like events in Super-Kamiokande, IceCube, and other detectors. We present new limits and propose several new analyses, in particular, for the Super-Kamiokande experiment, which can probe a previously unexplored portion of the millicharged dark matter parameter space. Most of our results are fairly general and apply to a broad class of dark matter models.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The site-selective functionalization of unactivated aliphatic amines is an attractive and challenging synthetic approach. We herein report a general strategy for the remote site-selective ...functionalization of unactivated C(sp3)–H bonds in amides by photogenerated amidyl radicals to form gem-difluoroalkenes with trifluoromethyl-substituted alkenes. The site selectivity is controlled by a 1,5-hydrogen atom transfer (HAT) process of the amide. This photocatalyzed transformation shows both chemo- and site-selectivity, facilitating the formation of a secondary, tertiary, or quaternary carbon center.
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Fennel (Foeniculum vulgare Mill.) is widely cultivated and used as a culinary spice. In this work, the chemical composition of the essential oil obtained by hydrodistillation of fennel seeds was ...analyzed by gas chromatography-mass spectrometry (GC–MS), and 28 components were identified. Trans-anethole (68.53%) and estragole (10.42%) were found to be the major components. The antibacterial activity, minimum inhibitory concentration (MIC), and minimum bactericide concentration (MBC) of essential oil against several food-borne pathogens were evaluated. The results showed that the gram positive and gram negative strains of bacteria had different sensitivities to essential oil of fennel seeds, the essential oil exhibited antibacterial activity against Staphylococcus albus, Bacillus subtilis, Salmonella typhimurium, Shigella dysenteriae and Escherichia coli according to the results of MIC and MBC. Among these bacteria, S. dysenteriae was the most sensitive to essential oil, showing the lowest MIC and MBC values of 0.125 and 0.25 mg/mL respectively. In addition, kill-time assay also showed that the essential oil had a significant effect on the growth rate of surviving S. dysenteriae. We concluded that the mechanism of action of the essential oil against S. dysenteriae might be described as essential oil acting on membrane integrity according to the results of the leakage of electrolytes, the losses of contents (proteins, reducing sugars and 260 nm absorbing materials) assays and electron microscopy observation.
•Analyzed the chemical compositions of essential oil from fennel seeds.•Investigated the antibacterial activity of essential oil from fennel seeds.•Evaluated the action mechanism of essential oil against Shigella dysenteriae.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Recent developments in the field of cellular therapeutics have indicated the potential of stem cell injections directly to the spinal cord. Injections require either open surgery or a Magnetic ...Resonance Imaging (MRI) guided injection. Needle positioning during MRI imaging is a significant hurdle to direct spinal injection, as the small target region and interlaminar space require high positioning accuracy. Objective: To improve both the procedure time and positioning accuracy, an MRI guided robotic needle positioning system is developed. Methods: The robot uses linear piezoelectric motors to directly drive a parallel plane positioning mechanism. Feedback is provided through MRI during the orientation procedure. Both accuracy and repeatability of the robot are characterized. Results: This system is found to be capable of repeatability below 51 μm. Needle endpoint error is limited by imaging modality, but is validated to 156 μm. Conclusion: The reported robot and MRI image feedback system is capable of repeatable and accurate needle guide positioning. Significance : This high accuracy will result in a significant improvement to the workflow of spinal injection procedures.
The objective of this study is to explore the role of MALAT1 as a molecular indicator in predicting the recurrence, metastasis, and prognosis of gallbladder cancer (GBC) and its effect on the ...proliferation, invasion, migration, and apoptosis of GBC cells in vitro. GBC tissues and adjacent normal tissues were collected from 102 patients. MALAT1 short hairpin RNA (shRNA) plasmids were first constructed to transfect the GBC‐SD cells. Reverse transcription quantitative polymerase chain reaction (RT‐qPCR) was applied to detect MALAT1 expression. CCK‐8 assay, flow cytometry, and Transwell assay were applied to testify the cell proliferation, cell cycle, apoptosis, invasion, and migration. A receiver operating characteristic (ROC) curve was used to evaluate the values of MALAT1 in GBC recurrence, metastasis, and prognosis. COX regression analysis was applied to analyze the independent influencing factors of GBC patients’ survival status. ROC curve results showed that the MALAT1 expression could be a predictor of the GBC recurrence, metastasis, and prognosis. According to the COX regression analysis, MALAT1 expression, tumor size, and TNM stage were independent influencing factors of GBC patients’ survival condition. Compared with the GBC‐SD cells transfected with empty plasmids, those transfected with MALAT1 shRNA plasmids showed higher apoptosis rates, weakened proliferation, migration, and invasion. In conclusion, our findings demonstrate that lncRNA MALAT1 can be considered as an indicator for evaluating the recurrence, metastasis, and prognosis of GBC patients. We also demonstrate how the overexpression of MALAT1 confers an oncogenic function in GBC.
Our findings demonstrate that lncRNA MALAT1 can be considered as an indicator for evaluating the recurrence, metastasis, and prognosis of GBC patients. We also demonstrate how the overexpression of MALAT1 confers an oncogenic function in GBC.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Cobalt chalcogenides CoX2 (X=S, Se, Te) render great performance of lithium‐sulfur batteries based on catalytic capacity to alleviate shuttle effect. Given that S/Se/Te belong to the same main group, ...the outstanding cycling stability delivered by CoTe2 aroused the curiosity about the uniqueness of CoTe2 and intrinsic laws of cobalt chalcogenide. Herein, comprehensive theoretical study delivers new insights into the intrinsic laws of CoX2: the relative vertical distance of two X atomic layers (rather than atom electronegativity) mainly controls adsorption; CoX2 mainly regulates the charging process (rather than discharging process) thus contributes to great cycling stability. On this basis, the advantages of CoTe2 are three‐fold: moderate polysulfide adsorption, facile ion transport capacity, and surprisingly great promotion of charging process. It is hope the results will facilitate the development of cobalt chalcogenides, especially tellurides as catalytic material in lithium sulfur batteries.
Theoretical study delivers new insights into catalytic cobalt chalcogenides CoX2 (X=S, Se, Te) in lithium‐sulfur battery. The polysulfides adsorption is mainly controled by relative vertical distance of two X atomic layers (rather than atom electronegativity). The charging process (rather than discharging process) is mainly regulated to contribute to steady polysulfides conversion.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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