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Find video protocols related to scientific articles indexed in Pubmed.
A Genetically Encoded Alkyne Directs Palladium-Mediated Protein Labeling on Live Mammalian Cell Surface.
ACS Chem. Biol.
PUBLISHED: 10-28-2014
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The merging of site-specific incorporation of small bioorthogonal functional groups into proteins via amber codon suppression with bioorthogonal chemistry has created exciting opportunities to extend the power of organic reactions to living systems. Here we show that a new alkyne amino acid can be site-selectively incorporated into mammalian proteins via a known orthogonal pyrrolysyl-tRNA synthetase/tRNACUA pair and directs an unprecedented, palladium-mediated cross-coupling reaction-driven protein labeling on live mammalian cell surface. A comparison study with the alkyne-encoded proteins in vitro indicated that this terminal alkyne is better suited for the palladium-mediated cross-coupling reaction than the copper-catalyzed click chemistry.
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Association of vitamin D receptor gene polymorphisms with the susceptibility to ulcerative colitis in patients from Southeast China.
J. Recept. Signal Transduct. Res.
PUBLISHED: 10-28-2014
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Abstract The association studies from different ethnic groups showed that vitamin D receptor (VDR) gene polymorphisms might be connected with the susceptibility to ulcerative colitis (UC); however, the conclusions were less consistent. Our study aimed to analyze the associations of UC with common mutations of VDR in Chinese patients. A total of 382 UC patients and 489 healthy controls were recruited. The genotypes of VDR FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232) and TaqI (rs731236) were examined by SNaPshot assays. Haplotype analysis was performed in all study subjects. After Bonferroni correction, the mutant alleles and genotypes of VDR FokI, BsmI, ApaI and TaqI did not statistically differ between UC patients and the controls (all p?>?0.0125). However, the mutant allele C and genotype TC?+?CC of FokI gene were significantly increased in patients with mild and moderate UC compared to those with severe UC (C allele: 54.1% versus 39.3%, OR?=?1.83, 95% CI: 1.21-2.75, p?=?0.004; TC?+?CC genotype: 81.6% versus 57.1%, OR?=?3.32, 95% CI: 1.83-6.06, p?
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[Effect of dangua recipe on glycolipid metabolism and VCAM-1 and its mRNA expression level in Apo E(-/-) mice with diabetes mellitus].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 10-23-2014
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To study the effect of Dangua Recipe (DGR) on glycolipid metabolism, vascular cell adhesion molecule-1 (VCAM-1) and its mRNA expression level of transgenic Apo E(-/-) mouse with spontaneous atherosclerosis, thus revealing its partial mechanism for curing diabetes mellitus (DM) with angiopathy.
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The complete mitochondrial genome of Eremias przewalskii (Squamata: Lacertidae).
Mitochondrial DNA
PUBLISHED: 10-17-2014
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Abstract In this paper, the complete mitochondrial genome of Eremias przewalskii (Squamata: Lacertidae) is reported, which is a circular molecule of 18,225?bp in size. The base composition of mtDNA is as follows: 30.3% A, 27.9% T, 27.9% C and 13.9% G. The genome consists of 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNA genes and one putative control region.
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Two isoreticular metal-organic frameworks with CdSO4-like topology: selective gas sorption and drug delivery.
Dalton Trans
PUBLISHED: 10-14-2014
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Two isoreticular metal-organic frameworks with chemical formulae [Cu(L)(4,4'-bipy)(H2O)]n 1.5nCH3CN () and [Cu(L)(4,4'-bipy)(H2O)]n·4nH2O () (H2L = diphenylmethane-4,4'-dicarboxylic acid) were synthesized and structurally characterized. They show the CdSO4 (6(5) 8) net and have an obvious 1D channel that is spread along the crystallographic c axis. More importantly, shows high selectivity for H2 over N2 and CO2 at low pressure, which could be confirmed via computational calculations using the Connolly algorithm to reveal the size and shape of accessible voids. The incorporation of the drug 5-fluorouracil (5-FU) into the desolvated was around 27.5 wt% per gram of the dehydrated . 5-FU is released in a highly controlled and progressive fashion with 61% of the drug released after 95 hours. In addition, we have applied molecular docking calculations to investigate the preferred conformation of 5-FU molecules upon binding to MOF . These calculations provide a structural basis to explain the 5-FU release from MOF .
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Melatonin enhances plant growth and abiotic stress tolerance in soybean plants.
J. Exp. Bot.
PUBLISHED: 10-10-2014
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Melatonin is a well-known agent that plays multiple roles in animals. Its possible function in plants is less clear. In the present study, we tested the effect of melatonin (N-acetyl-5-methoxytryptamine) on soybean growth and development. Coating seeds with melatonin significantly promoted soybean growth as judged from leaf size and plant height. This enhancement was also observed in soybean production and their fatty acid content. Melatonin increased pod number and seed number, but not 100-seed weight. Melatonin also improved soybean tolerance to salt and drought stresses. Transcriptome analysis revealed that salt stress inhibited expressions of genes related to binding, oxidoreductase activity/process, and secondary metabolic processes. Melatonin up-regulated expressions of the genes inhibited by salt stress, and hence alleviated the inhibitory effects of salt stress on gene expressions. Further detailed analysis of the affected pathways documents that melatonin probably achieved its promotional roles in soybean through enhancement of genes involved in cell division, photosynthesis, carbohydrate metabolism, fatty acid biosynthesis, and ascorbate metabolism. Our results demonstrate that melatonin has significant potential for improvement of soybean growth and seed production. Further study should uncover more about the molecular mechanisms of melatonin's function in soybeans and other crops.
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Chemo-, Regio-, and Stereoselective Trifluoromethylation of Styrenes via Visible Light-Driven Single-Electron Transfer (SET) and Triplet-Triplet Energy Transfer (TTET) Processes.
J. Org. Chem.
PUBLISHED: 10-09-2014
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A process for tunable and chemo-, regio-, and stereoselective photocatalytic trifluoromethylation of styrenes was developed. Thermodynamically stable E-trifluoromethylated alkenes were prepared using Togni's reagent in the presence of Ru(bpy)3Cl2·6H2O under visible light irradiation, whereas less thermodynamically stable Z-trifluoromethylated alkenes were obtained by employing Umemoto's reagent and photocatalyst Ir(ppy)3.
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Synthesis of cell-permeable stapled BH3 peptide-based Mcl-1 inhibitors containing simple aryl and vinylaryl cross-linkers.
Tetrahedron
PUBLISHED: 10-01-2014
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We report the synthesis of a series of distance-matching aryl and vinylaryl cross-linkers for constructing stapled peptides containing cysteines at i,i+7 positions. Langevin dynamics simulation studies helped to classify these cross-linkers into two categories: the rigid cross-linkers with narrower S-S distance distribution and the flexible cross-linkers with wider S-S distance distribution. The stapled Noxa BH3 peptides with the flexible distance-matching cross-linkers gave the highest degree of helicity as well as the most potent inhibitory activity against Mcl-1. However, the stapled peptides with the highest hydrophobicity showed the most efficient cellular uptake. Together, this work illustrates the divergent nature of binding affinity and cellular uptake, and the vital importance of choosing appropriate cross-linkers in constructing stapled peptides with the drug-like properties.
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The nearly complete mitochondrial genome of the rapid racerunner Eremias velox (Squamata: Lacertidae).
Mitochondrial DNA
PUBLISHED: 09-30-2014
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Abstract We report the nearly complete mitochondrial genome of the rapid racerunner, Eremias velox (Lacertidae), which is a circular molecule of 18,033?bp in size and consists of 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and a partial control region (2627?bp). The A?+?T content of overall base composition of H-strand is 58.0% (T: 27.7%, C: 28.3%, A: 30.3%, G: 13.7%). Some short microsatellite-like repeat regions (polyA and polyT) are scattered in the control region. All the results provide powerful data for further study of the molecular systematics, species identification and conservation genetics in this species and its congenators.
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Step-by-Step Fracture of Two-Layer Stacked Graphene Membranes.
ACS Nano
PUBLISHED: 09-29-2014
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Layer-by-layer assembly of graphene has been proven to be an effective way to improve its mechanical properties, but its fracture mechanism, which is crucial for practical device applications, is still not clear and has not been fully studied yet. By consecutive stacking of two graphene monolayers, we fabricate two-layer stacked graphene membranes with a clean interface between the two layers. Fracture behavior of the two-layer stacked graphene membranes is studied using nanoindentation performed by atomic force microscopy. It is found that the fracture force distribution of stacked graphene is very different from that of monolayer graphene. Weibull statistics of fracture forces show that after layer-by-layer stacking of graphene, the membrane becomes less sensitive to the defects during nanoindentation, improving the overall performance of the graphene membranes. Interestingly, a third of our tested membranes show a stepwise fracture, which could serve as a warning message for the mechanical failure of multilayer graphene devices. Our study provides insight into the fracture mechanism of multilayer graphene membranes.
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The complete mitochondrial genome of Eremias multiocellata (Squamata: Lacertidae).
Mitochondrial DNA
PUBLISHED: 09-12-2014
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Abstract In this paper, the complete mitochondrial genome of Eremias multiocellata (Squamata: Lacertidae) is reported, which is a circular molecule of 19,385?bp in size. The nucleotides composition are 31.2% A, 28.9% T, 27.1% C and 13.4% G. The genome consists of 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNA genes and 1 putative control region.
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Initial study of biexponential model of intravoxel incoherent motion magnetic resonance imaging in evaluation of the liver fibrosis.
Chin. Med. J.
PUBLISHED: 09-06-2014
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The diagnosis of liver fibrosis is a difficult task at any time using conventional clinical imaging. Intravoxel incoherent motion (IVIM) can be used to investigate both diffusion and perfusion changes in tissues. This study was designed to determine the value of IVIM in the diagnosis and staging of liver fibrosis.
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[Apoptosis of melanoma B16 cells induced by gambogenic acid].
Zhong Yao Cai
PUBLISHED: 09-02-2014
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To study the inhibitory effect of Gambogenic acid (GNA) on melanoma B16 cells proliferation, and to explore the role of cell apoptosis.
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The complete mitochondrial genome of Eremias vermiculata (Squamata: Lacertidae).
Mitochondrial DNA
PUBLISHED: 08-27-2014
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Abstract In this paper, we report the complete mitochondrial genome of Eremias vermiculata (Squamata: Lacertidae), which is a circular molecule of 19,914?bp in size and consists of 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and 1 putative control region. The A?+?T content of overall base of the composition of H-strand is 59.8% (T: 28.9%, C: 27.2%, A: 30.9%, G: 13.0%). All of the results provide powerful data to further study of the molecular systematics, species identification and conservation genetics.
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Highly sensitive fluorescent probe for clenbuterol hydrochloride detection based on its catalytic oxidation of eosine Y by NaIO4.
J Fluoresc
PUBLISHED: 08-27-2014
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A highly sensitive fluorescent probe for clenbuterol hydrochloride (CLB) detection has been first designed based on its catalytic effect on NaIO4 oxidating eosine Y (R). And this environment-friendly, simple, rapid, selective and sensitive fluorescent probe has been utilized to detect CLB in the practical samples with the results consisting with those obtained by GC/MS. The structures of R and CLB were characterized by infrared spectra. The mechanism of the proposed assay for the detection of CLB was also discussed.
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[Diagnostic role of contrast-enhanced whole-heart coronary magnetic resonance angiography in the evaluation of coronary artery disease].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-26-2014
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To prospectively evaluate the diagnostic effectiveness of contrast-enhanced whole-heart coronary magnetic resonance angiography (CE-CMRA) in patients with suspected coronary artery disease (CAD) with conventional coronary angiography as the reference standard.
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Storable N-phenylcarbamate palladacycles for rapid functionalization of an alkyne-encoded protein.
Chem. Commun. (Camb.)
PUBLISHED: 08-21-2014
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Here we report the synthesis of storable N-phenylcarbamate palladacycles that showed robust reactivity in the cross-coupling reaction with an alkyne-encoded protein with a second-order rate constant approaching 19?770 ± 930 M(-1) s(-1).
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Dan-gua Fang () improves glycolipid metabolic disorders by promoting hepatic adenosine 5'-monophosphate activated protein kinase expression in diabetic Goto-Kakizaki rats.
Chin J Integr Med
PUBLISHED: 08-07-2014
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To investigate the effect of Dan-gua Fang () on adenosine 5'-monophosphate (AMP) activated protein kinase (AMPK) ? expression in liver and subsequent improvement of glucose and lipid metabolism.
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[Study of gambogenic acid-induced apoptosis of melanoma B16 cells through PI3K/Akt/mTOR signaling pathways].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 08-07-2014
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To discuss the mechanism of gambogenic acid (GNA) in inducing the apoptosis of melanoma B16 cells.
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[Gambogenic acid induces mitochondria-dependent apoptosis in human gastric carcinoma cell line].
Zhong Yao Cai
PUBLISHED: 08-06-2014
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To study the effects of Gambogenic acid (GNA) on the growth of human gastric carcinoma cell line MGC-803 and its underlying mechanisms.
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A context-aware-based audio guidance system for blind people using a multimodal profile model.
Sensors (Basel)
PUBLISHED: 08-04-2014
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A wearable guidance system is designed to provide context-dependent guidance messages to blind people while they traverse local pathways. The system is composed of three parts: moving scene analysis, walking context estimation and audio message delivery. The combination of a downward-pointing laser scanner and a camera is used to solve the challenging problem of moving scene analysis. By integrating laser data profiles and image edge profiles, a multimodal profile model is constructed to estimate jointly the ground plane, object locations and object types, by using a Bayesian network. The outputs of the moving scene analysis are further employed to estimate the walking context, which is defined as a fuzzy safety level that is inferred through a fuzzy logic model. Depending on the estimated walking context, the audio messages that best suit the current context are delivered to the user in a flexible manner. The proposed system is tested under various local pathway scenes, and the results confirm its efficiency in assisting blind people to attain autonomous mobility.
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A Highly Sensitive Solid Substrate Room Temperature Phosphorimetry for Carbaryl Detection Based on its Activating Effect on NaIO4 Oxidizing Fluorescein.
J Fluoresc
PUBLISHED: 08-01-2014
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Fluorescein (HFin) could emit strong and stable room temperature phosphorescence (RTP) signal on polyamide membrane (PAM) using Pb(2+) as the ion perturber. Carbaryl could activate effect on NaIO4 oxidating HFin, which caused the RTP signal of the system to quench sharply. The phosphorescence intensity (?I p) of activating system higher 3.3 times (119.4/36.0) than that of non-activating system, and is directly proportional to the content of carbaryl. Thus, an activating solid substrate room temperature phosphorimetry (SSRTP) for carbaryl detection has been established. This sensitive (the limit of quantification (LOQ) was 2.0?×?10(-13) g mL(-1)), selective, simple and rapid method has been applied to determine trace carbaryl in water samples with the results consisting with those obtained by fluorimetry, showing its high accuracy. The apparent activation energy (E) and rate constant (k) of this activating reaction were 20.77 kJ mol(-1) and 1.85?×?10(-4) s(-1), respectively. Meanwhile, the mechanism of activating SSRTP for carbaryl detection was also discussed using infrared spectra (IR).
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Fast and sequence-specific palladium-mediated cross-coupling reaction identified from phage display.
ACS Chem. Biol.
PUBLISHED: 07-24-2014
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Fast and specific bioorthogonal reactions are highly desirable because they provide efficient tracking of biomolecules that are present in low abundance and/or involved in fast dynamic process in living systems. Toward this end, classic strategy involves the optimization of substrate structures and reaction conditions in test tubes, testing their compatibility with biological systems, devising synthetic biology schemes to introduce the modified substrates into living cells or organisms, and finally validating the superior kinetics for enhanced capacity in tracking biomolecules in vivo--a lengthy process often mired by unexpected results. Here, we report a streamlined approach in which the "microenvironment" of a bioorthogonal chemical reporter is exploited directly in biological systems via phage-assisted interrogation of reactivity (PAIR) to optimize not only reaction kinetics but also specificity. Using the PAIR strategy, we identified a short alkyne-containing peptide sequence showing fast kinetics (k2=13,000±2000 M(-1) s(-1)) in a palladium-mediated cross-coupling reaction. Site-directed mutagenesis studies suggested that the residues surrounding the alkyne moiety facilitate the assembly of a key palladium-alkyne intermediate along the reaction pathway. When this peptide sequence was inserted into the extracellular domain of epidermal growth factor receptor (EGFR), this reactive sequence directed the specific labeling of EGFR in live mammalian cells.
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Apertureless Cantilever-Free Pen Arrays for Scanning Photochemical Printing.
Small
PUBLISHED: 07-23-2014
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A novel, apertureless, cantilever-free pen array can be used for dual scanning photochemical and molecular printing. Serial writing with light is enabled by combining self-focusing pyramidal pens with an opaque backing between pens. The elastomeric pens also afford force-tuned illumination and simultaneous delivery of materials and optical energy. These attributes make the technique a promising candidate for maskless high-resolution photopatterning and combinatorial chemistry.
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Rifampicin Loaded Mannosylated Cationic Nanostructured Lipid Carriers for Alveolar Macrophage-specific Delivery.
Pharm. Res.
PUBLISHED: 07-11-2014
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In this study, cationic mannosylated nanostructured lipid carriers (Man-NLCs) were developed for the targeted delivery of rifampicin to alveolar macrophages.
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[PPAR-? agonist inhibits the expressions of chemokines induced by IFN-? and TNF-? in renal tubular epithelial cells].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 07-09-2014
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To investigate the effect of peroxisome proliferator-activated receptor-? (PPAR-?) agonist 15d-PGJ2 on the expressions of CXCL9, CXCL10 and CXCL11 in renal tubular epithelial cells (HK-2) stimulated by interferon-? (IFN-?) plus tumor necrosis factor-? (TNF-?).
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Development of a 5-fluorouracil-loaded PLGA microsphere delivery system by a solid-in-oil-in-hydrophilic oil (S/O/hO) novel method for the treatment of tumors.
Oncol. Rep.
PUBLISHED: 04-30-2014
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Tumor treatment requires a long-term regimen of chemotherapy, and both surgical tumor resection and radiation therapy are also used. The present study aimed to develop a novel method for 5-fluorouracil (5-FU)-loaded microspheres which enhance the therapeutic effects of chemotherapy, the quality of life of patients and reduce chemotherapy systemic side-effects. The preparation of a 5-FU microsphere delivery system by a solid-in-oil-in-hydrophilic oil (S/O/hO) novel method was carried out and then in vitro and in vivo evaluation of the 5-FU-microsphere delivery system was conducted. The 5-FU microsphere delivery system prepared had sustained-release function and achieved local treatment efficacy for tumors. The encapsulation efficiency of the 5-FU microsphere delivery system was >90% [better than the fabrication method using water-in-oil-in-water (W/O/W)]. The drug release profile from the 5-FU-loaded sustained-release microsphere delivery system matched the pseudo zero-order equation for 30 days in vitro. The plasma concentration of 5-FU was higher than the water solution by subcutaneous injection. The tumor growth rate of rabbits using the 5-FU microsphere delivery system was much lower than the rate in rabbit using a subcutaneous injection of 5-FU water solution. The 5-FU-loaded sustained-release microspheres using the novel method (S/O/hO) is a potential and effective method with which to inhibit tumor growth.
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Validated LC-MS/MS method for the simultaneous determination of chlorambucil and its prodrug in mouse plasma and brain, and application to pharmacokinetics.
J Pharm Biomed Anal
PUBLISHED: 04-30-2014
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A simple, sensitive and rapid LC-MS/MS method was developed and validated for the simultaneous determination of chlorambucil (CHL) and the prodrug of chlorambucil (CHLS) in mouse plasma and brain tissue. Detection was performed on a Diamonsil ODS chromatography column using gradient elution with a mobile phase of 0.2% aqueous formic acid and acetonitrile. Mass spectrometry was carried out in multiple reaction monitoring mode using a positive electrospray ionization interface. Good linearity was found for CHLS and CHL in plasma and brain tissue in different linear ranges (r>0.9996). Intra-day and inter-day precision was within 9.11% and accuracy was not more than 11.07%. The validated method was successfully applied to the pharmacokinetic study of CHLS and CHL in mice after intravenous administration.
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Design of highly sensitive phosphorescence sensor for determination of procaterol hydrochloride based on inhibition of KClO3 oxidation fluorescein isothiocyanate.
Luminescence
PUBLISHED: 04-24-2014
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Procaterol hydrochloride (Prh) can inhibit KClO3 oxidation of fluorescein isothiocyanate (FITC) to form a non-phosphorescent compound, which causes room temperature phosphorescence (RTP) of FITC in the system to enhance sharply the linear relationship between ?Ip and the Prh content. Thus, a rapid response and highly sensitive phosphorescence sensor for the determination of Prh has been developed based on the inhibiting effect of Prh on KClO3 oxidation of FITC. This simple, high sensitivity (detection limit (LD) calculated by 3Sb /k was 0.019 fg/spot, sample volume 0.40 µl, corresponding concentration 4.8?×?10(-14) g ml(-1) ) and selective sensor with a wide linear range (0.080-11.20 g/spot) has been applied to detect Prh in blood samples, and the results were consistent with those obtained by high-performance liquid chromatography (HPLC). Simultaneously, the mechanism of the phosphorescence sensor for the detection of Prh was also investigated using infrared spectroscopy. Copyright © 2014 John Wiley & Sons, Ltd.
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[Effect of chaperone-mediated autophagy in MPP(+) -induced SH-SY5Y cells and interventional effect of puerarin].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 04-24-2014
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To study the protective effect of puerarin on MPP(+) -induced SH-SY5Y cells by chaperone-mediated autophagy (CMA).
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The complete mitochondrial genome of Leiolepis reevesii (Sauria, Agamidae).
Mitochondrial DNA
PUBLISHED: 04-09-2014
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Abstract In this paper, we report the complete mitochondrial genome of Leiolepis reevesii (Sauria, Agamidae), which is a circular molecule of 16,908?bp in size and consists of 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and a control region. The A+T content of overall base composition of H-strand is 59.8% (T: 25.1%, C: 27.5%, A: 34.7%, G: 12.7%). Some short microsatellite-like repeat regions (polyA and polyT) are scattered in the control region. All the results provide powerful data to further study of the molecular systematics, species identification and conservation genetics.
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Photoclick chemistry: a fluorogenic light-triggered in vivo ligation reaction.
Curr Opin Chem Biol
PUBLISHED: 03-27-2014
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The ability to use chemical reactivity to monitor and control biomolecular processes with a spatial and temporal precision motivated the development of light-triggered in vivo chemistries. To this end, the photoinduced tetrazole-alkene cycloaddition, also termed 'photoclick chemistry' offers a very rapid chemical ligation platform for the manipulation of biomolecules and matrices in vivo. Here we outline the recent developments in the optimization of this chemistry, ranging from the search for substrates that offer two-photon photoactivatability, superior reaction kinetics, and/or genetic encodability, to the study of the reaction mechanism. The applications of the photoclick chemistry in protein labeling in vitro and in vivo as well as in preparing 'smart' hydrogels for 3D cell culture are highlighted.
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Associations of FUT2 and FUT3 gene polymorphisms with Crohn's disease in Chinese patients.
J. Gastroenterol. Hepatol.
PUBLISHED: 03-27-2014
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FUT2 and FUT3 genes are responsible for the formation of histo-blood group antigens, which act as binding sites for some intestinal microbes. Several studies suggested that FUT2 gene might affect the intestinal microbiota composition and modulate innate immune responses. However, the effect of FUT2 polymorphisms on Crohn's disease (CD) is uncertain. Our study aimed to analyze associations of CD with FUT2 and FUT3 polymorphisms in Chinese population.
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Design of spiro[2.3]hex-1-ene, a genetically encodable double-strained alkene for superfast photoclick chemistry.
J. Am. Chem. Soc.
PUBLISHED: 03-10-2014
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Reactive yet stable alkene reporters offer a facile route to studying fast biological processes via the cycloaddition-based bioorthogonal reactions. Here, we report the design and synthesis of a strained spirocyclic alkene, spiro[2.3]hex-1-ene (Sph), for an accelerated photoclick chemistry, and its site-specific introduction into proteins via amber codon suppression using the wild-type pyrrolysyl-tRNA synthetase/tRNA(CUA) pair. Because of its high ring strain and reduced steric hindrance, Sph exhibited fast reaction kinetics (k2 up to 34,000 M(-1) s(-1)) in the photoclick chemistry and afforded rapid (<10 s) bioorthogonal protein labeling.
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Structure, function, and pathogenesis of SHP2 in developmental disorders and tumorigenesis.
Curr Cancer Drug Targets
PUBLISHED: 03-04-2014
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Src homology 2 (SH2)-containing protein tyrosine phosphatase 2 (SHP2), encoded by the human PTPN11 gene, is a ubiquitously expressed protein tyrosine phosphatase (PTP) that consists of two tandem Src homology (SH2) domains (N-SH2 and C-SH2), a PTP catalytic domain, and a C-terminal tail with tyrosyl phosphorylation sites. It plays critical roles in numerous cellular processes through the regulation of various signaling pathways in PTP catalytic activity-dependent and -independent manners. Dysfunction of SHP2 resulting from pathogenic mutations and aberrant expression leads to the dysregulation of multiple signaling pathways, thus contributing to different human disorders. Germline and somatic mutations in PTPN11 are involved in Noonan syndrome (NS), LEOPARD syndrome (LS), and hematological malignancies, as well as several solid tumors. In this report, we provide an overview of the current knowledge of the structure and function of SHP2, and further discuss the molecular and pathogenic mechanism of SHP2 in human diseases, with a special focus on tumorigenesis. Furthermore, we summarize that SHP2 might itself represent a potential drug target for cancer prevention and treatment. Ongoing research and development of SHP2-specific inhibitors would enhance this potential.
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Atorvastatin Attenuates TNF-alpha Production via Heme Oxygenase-1 Pathway in LPS-stimulated RAW264.7 Macrophages.
Biomed. Environ. Sci.
PUBLISHED: 02-27-2014
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To assess the effect of atorvastatin on lipopolysaccharide (LPS)-induced TNF-? production in RAW264.7 macrophages.
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Identification of bovine NPC1 gene cSNPs and their effects on body size traits of Qinchuan cattle.
Gene
PUBLISHED: 02-24-2014
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NPC1 gene is an important gene closely related to the Niemann-Pick type C (NPC). Mutations in the NPC1 gene tend to cause Niemann-Pick type C, a lysosomal storage disorder. Previous studies have shown that NPC1 protein plays an important role in subcellular lipid transport, homeostasis, platelet function and formation, which are basic metabolic activities in the process of development. In this study, to explore the association between the NPC1 gene variation and body size traits in Qinchuan cattle, we detected four novel coding single nucleotide polymorphisms (cSNPs) in the bovine NPC1 gene, including one missense mutation (SNP1) and three synonymous mutations (SNP2, SNP3 and SNP4). Population genetic analyses of 518 individuals and association correlations between cSNPs and bovine body size traits were conducted in this research. A missense mutation at SNP1 locus was found to be significantly related to the heart girth, hip width and body weight (P<0.01 or P<0.05, 3.5-year-old). Two synonymous mutations at SNP2 and SNP3 loci also showed significant effects on hip width (P<0.05, 3.5-year-old). One synonymous mutation at SNP4 locus showed significant effect on body weight (P<0.05, 2.0-year-old). Combined haplotypes H2H6 and H6H6 showed significant effects on body size traits such as heart girth, hip width, and body weight (3.5-year-old, P<0.01 or P<0.05). This study provides evidence that the NPC1 gene might be involved in the regulation of bovine growth and body development, and may be considered as a candidate gene for marker assisted selection (MAS) in beef cattle breeding industry.
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Macrophage migration inhibitory factor is overexpressed in pancreatic cancer tissues and impairs insulin secretion function of ?-cell.
J Transl Med
PUBLISHED: 02-17-2014
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Understanding the pathogenic mechanism of pancreatic cancer associated diabetes (PCDM) might help yield biomarkers for the early diagnosis of pancreatic cancer (PC) from population with new-onset diabetes. In the current study, we sought to determine the role of macrophage migration inhibitory factor (MIF) in PCDM pathogenesis.
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Extracts from Curcuma zedoaria Inhibit Proliferation of Human Breast Cancer Cell MDA-MB-231 In Vitro.
Evid Based Complement Alternat Med
PUBLISHED: 02-14-2014
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Objective. To evaluate the effect of petroleum ether extracts of Curcuma zedoaria on the proliferation of human triple negative breast cancer cell line MDA-MB-231. Methods. The reagents were isolated from Curcuma zedoaria by petroleum ether fraction. It was assayed by CCK8 for MDA-MB-231 cellular viability with various concentrations and days, cell cycle analyses, Western Blot analysis, and Realtime Reverse Transcriptase PCR analyses for chemokines molecules including E-cadherin, and E-selectin, and adhesion molecules including CCR7, SLC, SDF-1, and CXCR4. Epirubicin was used as control in the study. Results. MDA-MB-231 cells were inhibited by petroleum ether extracts of Curcuma zedoaria (P < 0.05), and the inhibition rate was dependent on concentrations and time. Petroleum ether extracts of Curcuma zedoaria as well as Epirubicin produce a significant G0/G1 cell cycle arrest. The level of expression of proteins E-cadherin and E-cadherin mRNA was significantly increased, while proteins SDF-1, CCR7, and CXCR4 mRNA were decreased after being incubated with petroleum ether extracts of Curcuma zedoaria at the concentrations of 300? ? g/mL than control (P < 0.05). The differences were that the protein CXCR4 mRNA expression level was higher than vehicle. Conclusions. MDA-MB-231 cells were inhibited by petroleum ether extracts of Curcuma zedoaria.
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Genetic predisposition to Parkinson's disease and cancer.
Curr Cancer Drug Targets
PUBLISHED: 02-06-2014
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Parkinson's disease (PD) and cancer are often thought of as two sides of the same coin. At first glance, cancer and PD appear to have little in common. PD is caused by the degeneration of dopaminergic neurons, whereas cancer results from the uninhibited growth of tumor cells. Increasing numbers of genetic studies suggest that the pathogenesis of PD and cancer may involve similar genes, pathways, and mechanisms. The differences in the pathological and cellular mechanisms, and the associated genetic mutations, may result in two such divergent diseases. In this article, we highlight some molecular mechanisms and key biomarkers which might cause those two diseases from misfolding and degradation of proteins, mitochondrial damage, oxidative stress response, cell cycle control and DNA repair, and the PI3K/AKT/ mTOR pathway, in order to provide help to the understanding and treatment of these two diseases.
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Soybean GmMYB73 promotes lipid accumulation in transgenic plants.
BMC Plant Biol.
PUBLISHED: 01-29-2014
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Soybean is one of the most important oil crops. The regulatory genes involved in oil accumulation are largely unclear. We initiated studies to identify genes that regulate this process.
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Pharmacological mobilization of endogenous stem cells significantly promotes skin regeneration after full-thickness excision: the synergistic activity of AMD3100 and tacrolimus.
J. Invest. Dermatol.
PUBLISHED: 01-23-2014
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Stem cell therapy has shown promise in treating a variety of pathologies including skin wounds, but practical applications remain elusive. Here, we demonstrate that endogenous stem cell mobilization produced by AMD3100 and low-dose tacrolimus is able to reduce by 25% the time of complete healing of full-thickness wounds created by surgical excision. Equally important, healing was accompanied by reduced scar formation and regeneration of hair follicles. Searching for mechanisms, we found that AMD3100 combined with low-dose tacrolimus mobilized increased number of lineage-negative c-Kit+, CD34+, and CD133+ stem cells. Low-dose tacrolimus also increased the number of SDF-1-bearing macrophages in the wound sites amplifying the "pull" of mobilized stem cells into the wound. Lineage tracing demonstrated the critical role of CD133 stem cells in enhanced capillary and hair follicle neogenesis, contributing to more rapid and perfect healing. Our findings offer a significant therapeutic approach to wound healing and tissue regeneration.
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Long non-coding RNAs in stem cells and cancer.
World J Clin Oncol
PUBLISHED: 01-22-2014
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An overwhelming majority of the transcribed genome encodes for non-coding RNA (ncRNA) sequences. Deep sequencing of the transcriptome has uncovered tens of thousands of long ncRNA (lncRNA) sequences. However, little is known regarding the possible functions for a vast majority of these sequences. Among those lncRNAs whose function has been experimentally validated, most serve as regulators of gene expression. LncRNAs have been found to be critical to development and homeostasis and they have been implicated in several pathologies including cancer. Here, we examine the functions and underlying mechanisms of lncRNAs in stem cells and in cancer biology, areas linked by the actions of lncRNAs.
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Targeted delivery of ubiquitin-conjugated BH3 peptide-based Mcl-1 inhibitors into cancer cells.
Bioconjug. Chem.
PUBLISHED: 01-22-2014
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BH3 peptides are key mediators of apoptosis and have served as the lead structures for the development of anticancer therapeutics. Previously, we reported the application of a simple cysteine-based side chain cross-linking chemistry to NoxaBH3 peptides that led to the generation of the cross-linked NoxaBH3 peptides with increased cell permeability and higher inhibitory activity against Mcl-1 ( Muppidi, A., Doi, K., Edwardraja, S., Drake, E. J., Gulick, A. M., Wang, H.-G., Lin, Q. ( 2012 ) J. Am. Chem. Soc. 134 , 14734 ). To deliver cross-linked NoxaBH3 peptides selectively into cancer cells for enhanced efficacy and reduced systemic toxicity, here we report the conjugation of the NoxaBH3 peptides with the extracellular ubiquitin, a recently identified endogenous ligand for CXCR4, a chemokine receptor overexpressed in cancer cells. The resulting ubiquitin-NoxaBH3 peptide conjugates showed increased inhibitory activity against Mcl-1 and selective killing of the CXCR4-expressing cancer cells. The successful delivery of the NoxaBH3 peptides by ubiquitin into cancer cells suggests that the ubiquitin/CXCR4 axis may serve as a general route for the targeted delivery of anticancer agents.
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Angiotensin II-derived reactive oxygen species promote angiogenesis in human late endothelial progenitor cells through heme oxygenase-1 via ERK1/2 and AKT/PI3K pathways.
Inflammation
PUBLISHED: 01-21-2014
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Angiotensin II (Ang II), the main component of renin-angiotensin system, could mediate pathogenic angiogenesis in cardiovascular disorders. Late endothelial progenitor cells (EPCs) possess potent self-renewal and angiogenic potency superior to early EPCs, but few study focused on the cross-talk between Ang II and late EPCs. We observed that Ang II could increase reactive oxygen species (ROS) and promote capillary formation in late EPCs. Ang II-derived ROS could also upregulate heme oxygenase-1 (HO-1) expression, and treating late EPCs with HO-1 small interfering RNA or heme oxygenase inhibitor (HO inhibitor) could inhibit Ang II-induced tube formation and increase ROS level and apoptosis rate. In addition, PD98059 and LY294002 pretreatment attenuated Ang II-induced HO-1 expression. Accordingly, Ang II-derived ROS could promote angiogenesis in late EPCs by inducing HO-1 expression via ERK1/2 and AKT/PI3K pathways, and we believe HO-1 might be a promising intervention target in EPCs due to its potent proangiogenic, antioxidant, and antiapoptosis potentials.
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Levels of lymphocyte subsets in peripheral blood prior treatment are associated with aggressive breast cancer phenotypes or subtypes.
Med. Oncol.
PUBLISHED: 01-19-2014
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The aim of this study was to assess associations between ER, Ki67, Her-2 phenotypes, molecular subtypes of breast cancer and circulating levels of lymphocyte subsets (CD4+, CD8+, NK, CD19+, CD20+) and the ratio of CD4+ to CD8+ prior to treatment. Cells from peripheral blood were counted by flow cytometry, ER, Her-2, and Ki67 expressions were detected by pathological examination, and Her-2 was also detected by FISH. We conducted a case-case comparison of 494 women with newly diagnosed breast cancer to evaluate association between levels of lymphocyte subsets in peripheral blood and breast cancer phenotypes [ER- vs. ER+; Ki67 ? 14 % vs. Ki67 < 14 %; Her-2+ vs. Her-2-; triple-negative breast cancer (TNBC) vs. luminal A]. Women with the highest levels of CD3+ (OR 0.45, 95 % CI 0.22-0.94), CD4+ (OR 0.22, 95 % CI 0.08-0.59), and the ratio of CD4+/CD8+ (OR 0.17, 95 % CI 0.06-0.47) were least likely to have TNBCs compared with luminal A cancers. The highest tertile of CD8+ (OR 3.67, 95 % CI 1.06-12.72) and NK (OR 2.64, 95 % CI 1.12-6.24) was significantly associated with TNBC compared with luminal A cancer. ER-, Ki67 ? 14 %, Her-2+ were associated with low levels of CD4+ and CD4+/CD8+ compared with ER+, Ki67 < 14 %, Her-2-. Women in the highest level of CD8+ had more likelihood to have ER- and Her-2+ compared with ER+ and Her-2-. High levels of NK cells were associated with increased risk of ER- compared with ER+ cancers. Highest levels of CD19+ and CD20+ were associated with low risk of ER-, compared with ER+ cancers. These findings show that immune function differs among different breast cancer phenotypes or subtypes and is associated with ER-, Her-2+, Ki67 ? 14 %, and TNBC which are likely to be aggressive phenotypes.
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Design of antiviral stapled peptides containing a biphenyl cross-linker.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-18-2014
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Here we report the design and synthesis of a panel of stapled peptides containing a distance-matching biphenyl cross-linker based upon a peptide capsid assembly inhibitor reported previously. Compared with the linear peptide, the biphenyl-stapled peptides exhibited significantly enhanced cell penetration and potent antiviral activity in the cell-based infection assays. Isothermal titration calorimetry and surface plasmon resonance experiments revealed that the most active stapled CAI peptide binds to the C-terminal domain of HIV capsid protein as well as envelop glycoprotein gp120 with low micromolar binding affinities, and as a result, inhibits both the HIV-1 virus entry and the virus assembly.
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Atractylenolide-I sensitizes human ovarian cancer cells to paclitaxel by blocking activation of TLR4/MyD88-dependent pathway.
Sci Rep
PUBLISHED: 01-06-2014
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Paclitaxel, a known TLR4 ligand, leads to activation of TLR4/MyD88-dependent pathway that mediates chemoresistance and tumor progression in epithelial ovarian carcinoma (EOC). Atractylenolide-I (AO-I), a novel TLR4-antagonizing agent, inhibits TLR4 signaling by interfering with the binding of LPS or paclitaxel to membrane TLR4 of human leukocytes. In this study, AO-I was found to attenuate paclitaxel-induced protein expression of IL-6, VEGF and survivin, and to enhance early apoptosis and growth inhibition in MyD88(+) EOC cells; AO-I was shown to fit into the hydrophobic pocket of human MD-2 and to partially overlap with the binding site of paclitaxel by docking simulations, suggesting that AO-I may block the MD-2-mediated TLR4/MyD88-dependent paclitaxel signaling in MyD88(+) EOC cells. Therefore, AO-I could significantly sensitize the response of MyD88(+) EOC cells to paclitaxel by blocking MD-2-mediated TLR4/MyD88 signaling, and that AO-I-paclitaxel combination could be a promising strategy for the treatment of EOC with a functional TLR4/MyD88/NF-?B pathway.
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Oxygen-carbon nanotubes as a chemotherapy sensitizer for paclitaxel in breast cancer treatment.
PLoS ONE
PUBLISHED: 01-01-2014
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To study the in vivo and in vitro effects of adding oxygen carbon nanotubes (CNTs) to chemotherapy for breast cancer.
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Disappearance of GFP-positive hepatocytes transplanted into the liver of syngeneic wild-type rats pretreated with retrorsine.
PLoS ONE
PUBLISHED: 01-01-2014
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Green fluorescent protein (GFP) is a widely used molecular tag to trace transplanted cells in rodent liver injury models. The differing results from various previously reported studies using GFP could be attributed to the immunogenicity of GFP.
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[Risk factors and short-term prognosis of acute kidney injury in elderly patients].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 12-24-2013
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To explore the risk factors and short-term outcomes of acute kidney injury (AKI) in elderly patients.
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Effect of different water conditions on dissolution of nanosilver.
Water Sci. Technol.
PUBLISHED: 11-05-2013
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This study evaluates the time-dependent dissolution of nanosilver (nAg) in common electrolytes and natural waters. nAg was synthesized via Tollens method using sodium citrate as stabilizer; its morphology, UV-Vis spectrum, and particle size were characterized. The dissolved silver was monitored over time using filtration, centrifugation, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Our results indicated that nanoparticle aggregation, Cl(-) presence, and natural organic compounds could affect the dissolution behavior of nAg. The dissolution of nAg was highly dependent on Cl(-) concentration. Excessive Cl(-) enhanced nanoparticle dissolution, whereas natural organic compound inhibited the dissolution. The dissolution data fitted well with the first-order kinetic model, and the dissolution rate coefficients were calculated using the first-order equation. This study showed the dissolution of nAg under various water conditions. The obtained results may be helpful in predicting nAg behavior in relevant environmental aquatic systems.
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Fluorogenic, two-photon-triggered photoclick chemistry in live mammalian cells.
J. Am. Chem. Soc.
PUBLISHED: 10-31-2013
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The tetrazole-based photoclick chemistry has provided a powerful tool to image proteins in live cells. To extend photoclick chemistry to living organisms with improved spatiotemporal control, here we report the design of naphthalene-based tetrazoles that can be efficiently activated by two-photon excitation with a 700 nm femtosecond pulsed laser. A water-soluble, cell-permeable naphthalene-based tetrazole was identified that reacts with acrylamide with the effective two-photon cross-section for the cycloaddition reaction determined to be 3.8 GM. Furthermore, the use of this naphthalene-tetrazole for real-time, spatially controlled imaging of microtubules in live mammalian cells via the fluorogenic, two-photon-triggered photoclick chemistry was demonstrated.
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Bioorthogonal chemistry: strategies and recent developments.
Chem. Commun. (Camb.)
PUBLISHED: 10-23-2013
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The use of covalent chemistry to track biomolecules in their native environment-a focus of bioorthogonal chemistry-has received considerable interest recently among chemical biologists and organic chemists alike. To facilitate wider adoption of bioorthogonal chemistry in biomedical research, a central effort in the last few years has been focused on the optimization of a few known bioorthogonal reactions, particularly with respect to reaction kinetics improvement, novel genetic encoding systems, and fluorogenic reactions for bioimaging. During these optimizations, three strategies have emerged, including the use of ring strain for substrate activation in the cycloaddition reactions, the discovery of new ligands and privileged substrates for accelerated metal-catalysed reactions, and the design of substrates with pre-fluorophore structures for rapid "turn-on" fluorescence after selective bioorthogonal reactions. In addition, new bioorthogonal reactions based on either modified or completely unprecedented reactant pairs have been reported. Finally, increasing attention has been directed toward the development of mutually exclusive bioorthogonal reactions and their applications in multiple labeling of a biomolecule in cell culture. In this feature article, we wish to present the recent progress in bioorthogonal reactions through the selected examples that highlight the above-mentioned strategies. Considering increasing sophistication in bioorthogonal chemistry development, we strive to project several exciting opportunities where bioorthogonal chemistry can make a unique contribution to biology in the near future.
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[Simultaneous determination of formononetin, calycosin and isorhamnetin from Astragalus mongholicus in rat plasma by LC-MS/MS and application to pharmacokinetic study].
Zhong Yao Cai
PUBLISHED: 10-19-2013
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To establish a method to determine the concentration of formononetin, calycosin and isorhamnetin from Astragalus mongholicus in rats plasma using LC-MS/MS and calculate their pharmacokinetic parameters.
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An S-Domain Receptor-Like Kinase, OsSIK2, Confers Abiotic Stress Tolerance and Delays Dark-Induced Leaf Senescence in Rice.
Plant Physiol.
PUBLISHED: 10-18-2013
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Receptor-like kinases play important roles in plant development and defense responses; however, their functions in other processes remain unclear. Here, we report that OsSIK2, an S-domain receptor-like kinase from rice (Oryza sativa), is involved in abiotic stress and the senescence process. OsSIK2 is a plasma membrane-localized protein with kinase activity in the presence of Mn(2+). OsSIK2 is expressed mainly in rice leaf and sheath and can be induced by NaCl, drought, cold, dark, and abscisic acid treatment. Transgenic plants overexpressing OsSIK2 and mutant sik2 exhibit enhanced and reduced tolerance to salt and drought stress, respectively, compared with the controls. Interestingly, a truncated version of OsSIK2 without most of the extracellular region confers higher salt tolerance than the full-length OsSIK2, likely through the activation of different sets of downstream genes. Moreover, seedlings of OsSIK2-overexpressing transgenic plants exhibit early leaf development and a delayed dark-induced senescence phenotype, while mutant sik2 shows the opposite phenotype. The downstream PR-related genes specifically up-regulated by full-length OsSIK2 or the DREB-like genes solely enhanced by truncated OsSIK2 are all induced by salt, drought, and dark treatments. These results indicate that OsSIK2 may integrate stress signals into a developmental program for better adaptive growth under unfavorable conditions. Manipulation of OsSIK2 should facilitate the improvement of production in rice and other crops.
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Design and synthesis of laser-activatable tetrazoles for a fast and fluorogenic red-emitting 1,3-dipolar cycloaddition reaction.
Org. Lett.
PUBLISHED: 10-10-2013
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The design and synthesis of a new class of laser light activatable tetrazoles with extended ?-systems is reported. Upon 405 nm laser light irradiation, these bithiophene-substituted tetrazoles underwent extremely fast 1,3-dipolar cycloaddition reactions with dimethyl fumarate with second-order rate constants approaching 4000 M(-1) s(-1). The resulting pyrazoline cycloadducts exhibited solvent-dependent red fluorescence, making these tetrazoles potentially useful as fluorogenic probes for detecting alkenes in vivo.
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Design of oligothiophene-based tetrazoles for laser-triggered photoclick chemistry in living cells.
Chem. Commun. (Camb.)
PUBLISHED: 09-16-2013
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A 405 nm light-activatable terthiophene-based tetrazole was designed that reacts with a fumarate dipolarophile with the second-order rate constant k2 exceeding 10(3) M(-1) s(-1). The utility of this laser-activatable tetrazole in imaging microtubules in a spatiotemporally controlled manner in live cells was demonstrated.
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[Study on effect of psoralidin on anti-experimental postmenopausal osteoporosis and its mechanism].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-10-2013
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To observe the effect of psoralidine in rats with ovariectomy, and preliminarily study its mechanism.
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[The optimation of extraction technology of chuanxiong and xiangfu compatibility by SFE-CO2].
Zhong Yao Cai
PUBLISHED: 08-02-2013
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To optimize the extraction conditions of Chuanxiong and Xiangfu compatibility by supercritical CO2 and control the quality of the extract.
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Novel LC-MS/MS method for analyzing imperialine in rat plasma: development, validation, and application to pharmacokinetics.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 07-25-2013
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A sensitive, selective, rapid liquid chromatography-electrospray ionization-tandem mass spectrometric method was developed and validated in rat plasma to quantify imperialine, a major active constituent extracted from Bulbus Fritillariae Cirrhosae. Before analysis, plasma samples were pre-treated using cost-effective protein precipitation in order to extract imperialine and the internal standard, carbamzepine. The two analytes were then separated on a Diamonsil ODS chromatography column using gradient elution with a mobile phase of 0.1% aqueous formic acid and acetonitrile. Mass spectrometry was carried out in multiple reaction monitoring mode using a positive electrospray ionization interface. The calibration curve was linear (r(2)=0.9998) over the concentration range 2-1000ng/mL, while the validated limit of determination (LOD) was 0.5ng/mL. Precision varied from 0.1% to 7.1%, and the accuracy varied within ±2%. The method proved robust to sample freezing and thawing, as well as short- and long-term sample storage. The developed method was successfully applied to the pharmacokinetic study of imperialine in rats. Different amounts of imperialine were administered in single doses orally or through the caudal vena cava, and pharmacokinetic parameters were evaluated. Oral bioavailability with a dose of 1mg/kg was 31.2%; 5mg/kg, 53.6%; and 10mg/kg, 47.4%.
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Efficacy of mouth opening exercises in treating trismus after maxillectomy.
Chin. Med. J.
PUBLISHED: 07-24-2013
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Patients with maxillary tumor often suffer from trismus after maxillectomy, which could turn out to be a permanent sequela without proper intervention. In this study, the efficacy of mouth opening exercises in preventing and treating trismus was observed in patients with maxillary tumor early after their operations. At the same time, radiotherapy as an influencing factor for the mouth opening exercises was evaluated.
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PRDM16 rs2651899 Variant Is a Risk Factor for Chinese Common Migraine Patients.
Headache
PUBLISHED: 07-22-2013
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Recent genome-wide association studies (GWAS) have identified 3 loci in or near PRDM16 (1p36.32, rs2651899), LRP1 (12q13.3, rs11172113) and TRPM8 (2q37.1, rs10166942) in the population-based Womens Genome Health Study (WGHS) of migraine, and 2 loci in or near TRPM8 and LRP1 were repeated in European GWAS study. To evaluate whether the same variants are related to migraine in Chinese population, we investigated migraine with aura (MA) and migraine without aura (MO) patients of Chinese Han ethnicity in mainland China.
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[Value of 3-dimensional speckle tracking imaging to quantify regional left ventricular function in patients with coronary artery disease].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 07-15-2013
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To assess left ventricular (LV) strain by 3-dimensional speckle tracking imaging (3D-STI) in patients with coronary heart disease (CHD).
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Expression Levels and Significance of Nuclear Factor-?B and Epidermal Growth Factor Receptor in Hepatolithiasis Associated with Intrahepatic Cholangiocarcinoma.
Dig Surg
PUBLISHED: 07-14-2013
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Background: An increasing incidence of cholangiocarcinoma (CCA) and CCA mortality rates has been observed around the world. Patients with intrahepatic biliary stones have a 10% risk of developing CCA, and up to 70% of patients with histologically confirmed CCA have hepatolithiasis. Few previous studies have addressed the associations between the expression of nuclear factor (NF)-?B and epidermal growth factor receptor (EGFR) and clinicopathological prognosis in patients with hepatolithiasis-associated intrahepatic CCA. Aims: This study was designed to investigate the clinicopathological and prognostic significance of NF-?B and EGFR expression in hepatolithiasis-associated intrahepatic CCA and hepatolithiasis. Methods: A total of 90 liver specimens were immunohistochemically stained for NF-?B and EGFR expression, and the characteristics of 90 individual patients were retrospectively reviewed. Results: Differences in the positive rates of NF-?B and EGFR expression between the hepatolithiasis-associated intrahepatic CCA group, intrahepatic lithiasis group, and control group were found to be statistically significant. EGFR expression was closely associated with the degree of differentiation and depth of invasion (p < 0.05). The 1-, 3-, and 5-year overall survival rates were respectively 42.8, 21.0, and 10.3% in intrahepatic CCA groups. The survival rate of the EGFR-negative group was higher than in the EGFR-positive group (p < 0.01). Lymph node metastasis (HR 1.24, 95% CI 1.02-1.51) and EGFR positivity (HR 1.74, 95% CI 1.30-2.23) were associated with decreases in the survival rate. Conclusion: The expression of NF-?B may be an early step in intrahepatic cholangiocarcinogenesis. Overexpression of EGFR is associated with the degree of malignancy and with poor prognosis. NF-?B and EGFR may cooperate during intrahepatic cholangiocarcinogenesis and progression. Lymph node metastasis and EGFR positivity were associated with decreases in the survival rate.
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Storable palladacycles for selective functionalization of alkyne-containing proteins.
Chem. Commun. (Camb.)
PUBLISHED: 06-20-2013
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We report the facile preparation of palladacycles as storable arylpalladium(II) reagents from acetanilides via cyclopalladation. The palladacycles exhibit good stability in PBS buffer and are capable of functionalizing a metabolically encoded HPG-containing protein, thus providing a new type of biocompatible organometallic reagent for selectively functionalizing the alkyne-encoded proteins.
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Acute stress regulates nociception and inflammatory response induced by bee venom in rats: possible mechanisms.
Stress
PUBLISHED: 06-03-2013
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Restraint stress modulates pain and inflammation. The present study was designed to evaluate the effect of acute restraint stress on inflammatory pain induced by subcutaneous injection of bee venom (BV). First, we investigated the effect of 1?h restraint on the spontaneous paw-flinching reflex (SPFR), decrease in paw withdrawal mechanical threshold (PWMT) and increase in paw volume (PV) of the injected paw induced by BV. SPFR was measured immediately after BV injection, and PWMT and PV were measured 2?h before BV and 2-8?h after BV. The results showed that acute restraint inhibited significantly the SPFR but failed to affect mechanical hyperalgesia. In contrast, stress enhanced significantly inflammatory swelling of the injected paw. In a second series of experiments, the effects of pretreatment with capsaicin locally applied to the sciatic nerve, systemic 6-hydroxydopamine (6-OHDA), and systemic naloxone were examined on the antinociception and proinflammation produced by acute restraint stress. Local capsaicin pretreatment inhibited BV-induced nociception and inflammatory edema, and had additive effects with stress on nociception but reduced stress enhancement of edema. Systemic 6-OHDA treatment attenuated the proinflammatory effect of stress, but did not affect the antinociceptive effect. Systemic naloxone pretreatment eliminated the antinociceptive effect of stress, but did not affect proinflammation. Taken together, our data indicate that acute restraint stress contributes to antinociception via activating an endogenous opioid system, while sympathetic postganglionic fibers may contribute to enhanced inflammation in the BV pain model.
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Insulin and IGF-I inhibit GH synthesis and release in vitro and in vivo by separate mechanisms.
Endocrinology
PUBLISHED: 05-13-2013
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IGF-I is considered a primary inhibitor of GH secretion. Insulin may also play an important role in regulating GH levels because insulin, like IGF-I, can suppress GH synthesis and release in primary pituitary cell cultures and insulin is negatively correlated with GH levels in vivo. However, understanding the relative contribution insulin and IGF-I exert on controlling GH secretion has been hampered by the fact that circulating insulin and IGF-I are regulated in parallel and insulin (INSR) and IGF-I (IGFIR) receptors are structurally/functionally related and ubiquitously expressed. To evaluate the separate roles of insulin and IGF-I in directly regulating GH secretion, we used the Cre/loxP system to knock down the INSR and IGFIR in primary mouse pituitary cell cultures and found insulin-mediated suppression of GH is independent of the IGFIR. In addition, pharmacological blockade of intracellular signals in both mouse and baboon cultures revealed insulin requires different pathways from IGF-I to exert a maximal inhibitory effect on GH expression/release. In vivo, somatotrope-specific knockout of INSR (SIRKO) or IGFIR (SIGFRKO) increased GH levels. However, comparison of the pattern of GH release, GH expression, somatotrope morphometry, and pituitary explant sensitivity to acute GHRH challenge in lean SIRKO and SIGFRKO mice strongly suggests the primary role of insulin in vivo is to suppress GH release, whereas IGF-I serves to regulate GH synthesis. Finally, SIRKO and/or SIGFRKO could not prevent high-fat, diet-induced suppression of pituitary GH expression, indicating other factors/tissues are involved in the decline of GH observed with weight gain.
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Early clinical features and diagnosis of Dravet syndrome in 138 Chinese patients with SCN1A mutations.
Brain Dev.
PUBLISHED: 05-05-2013
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Objective: To summarize the early clinical features of Dravet syndrome (DS) patients with SCN1A gene mutations before the age of one. Methods: SCN1A gene mutation screening was performed by PCR-DNA sequencing and multiple ligation-dependent probe amplication (MLPA). The early clinical features of DS patients with SCN1A mutations were reviewed with attention to the seizures induced by fever and other precipitating factors before the first year of life. Results: The clinical data of 138 DS patients with SCN1A gene mutations were reviewed. The median seizure onset age was 5.3months. Ninety-nine patients (71.7%) experienced seizures with duration more than 15min in the first year of life. Two or more seizures induced by fever within 24h or the same febrile illness were observed in 93 patients (67.4%). 111 patients (80.4%) had hemi-clonic and (or) focal seizures. Seizures had been triggered by fever of low degree (T<38°C) in 62.3% (86/138) before the first year of life. Vaccine-related seizures were observed in 34.8% (48/138). Seizures in 22.5% (31/138) of patients were triggered by hot bath. Carbamazepine, oxcarbazepine, lamotrigine, phenobarbital and phenytoin showed either no effect or exacerbating the seizures in our group. Conclusion: The seizure onset age in DS patients was earlier than that was in common febrile seizures. When a baby exhibits two or more features of complex febrile seizures in the first year of life, a diagnosis of DS should be considered, and SCN1A gene mutation screening should be performed as early as possible. Early diagnosis of DS will help clinicians more effectively prescribe antiepileptic drugs for stronger prognosis.
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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.