JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
CO2 and temperature dual responsive "Smart" MXene phases.
Chem. Commun. (Camb.)
PUBLISHED: 11-20-2014
Show Abstract
Hide Abstract
A robust strategy is explored to graft poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) brushes on two-dimensional vanadium carbide (V2C) materials through self-initiated photografting and photopolymerization (SIPGP). CO2 and temperature dual-responsive properties of PDMAEMA allow this hybrid to be used as a smart system for tuning the transmittance and conductivity of V2C.
Related JoVE Video
Wavelength-locking-free 1.57µm differential absorption lidar for CO2 sensing.
Opt Express
PUBLISHED: 11-18-2014
Show Abstract
Hide Abstract
We propose a novel wavelength-locking-free differential absorption lidar system for CO2 sensing. The ON-line wavelength laser was wavelength modulated around a specific CO2 absorption line to ensure that the emission from the ON-line laser hit the atmospheric CO2 absorption line peak twice a cycle. In the meantime, the intensity of the ON-line and OFF-line wavelength lasers were sinusoidally intensity modulated to enhance the SNR of the back-scattered signal. As a consequence, the system configuration was simplified and the measurement error caused by the deviation of CO2 absorption coefficient from the long-time ON-line wavelength drifting was completely eliminated. Furthermore, a more precise calibration method was developed which could simultaneously calibrate the offset and precision of the lidar detector. This method could be applied to other differential-absorption-based lidar systems. The result showed that a measurement precision of 0.525% for the column concentration was achieved in 1 s time interval through a path of 780m. We recorded the CO2 concentration variation for 12 hours starting from mid-night, the result showed that the course of the concentration derived from the DIAL was in good agreement with that of the in situ CO2 sensor only when the status of atmosphere was stable.
Related JoVE Video
Temperature insensitive, high-power cascaded optical parametric oscillator based on an aperiodically poled lithium niobate crystal.
Opt Express
PUBLISHED: 11-18-2014
Show Abstract
Hide Abstract
We report a novel temperature insensitive, APMgLN-based, high-power cascaded optical parametric oscillator (OPO) pumped by an Ytterbium-doped fiber laser. A monolithic APMgLN crystal was designed to compensate the phase mismatches for the nonlinear conversions from the pump to the idler and the primary signal to the idler simultaneously in a wide temperature range. Efficient parametric conversion with pump-to-idler conversion efficiency over 15% and slope efficiency higher than 20% was realized from 25 °C to 55 °C. The idler wavelength was down-shifted from 3.82 ?m to 3.78 ?m accordingly during the temperature rise. The highest idler power of 4.1 W at 3.8 ?m under the pump power of 26.5 W was recorded which was improved by ~32% in pump-to-idler conversion efficiency when compared with the PPMgLN-based conventional OPO, in which the highest idler output power was 3.1W under the same pump and thermal condition.
Related JoVE Video
Dynamic Electrochemical Membranes for Continuous Affinity Protein Separation.
Adv Funct Mater
PUBLISHED: 11-11-2014
Show Abstract
Hide Abstract
A membrane system with nm-scale thick electrodes is able to selectively bind genetically modified proteins and pump them across the membrane with sequential voltage pulses. The electrodes are located at the first 20nm of pore entrances to specifically capture targeted proteins and block non-specific protein transport through the pores during the binding cycle. During the release cycle, concentration of imidazole is controlled to keep the pore blocked while releasing proteins at the bottom edge of the electrode. A separation factor for GFP:BSA of 16 was achieved with observed GFP electrophoretic mobility of 2.54×10(-6)cm(2)v(-1)S(-1). This non-optimized system with a membrane area of 0.75 cm(2) has the same throughput as 1ml of commercially available chromatography columns showing viability as a continuous process. This system will enable continuous separation of expressed proteins directly from fermentation broths dramatically simplifying the separation process as well as reducing biopharmaceutical production costs.
Related JoVE Video
Preparation and characterization of novel carbon dioxide adsorbents based on polyethylenimine-modified Halloysite Nanotubes.
Environ Technol
PUBLISHED: 11-11-2014
Show Abstract
Hide Abstract
ABSTRACT New nano-sized carbon dioxide (CO2) adsorbents based on Halloysite nanotubes (HNTs) impregnated with polyethylenimine (PEI) were designed and synthesized, which were excellent adsorbents for the capture of CO2 at room temperature and had relatively high CO2 adsorption capacity. The prepared adsorbents were characterized by various techniques such as Fourier transform-infrared spectrometry (FTIR), gel permeation chromatography (GPC), dynamic light scattering (DLS), thermogravimetry (TG), thermogravimetry-Fourier transform-infrared spectrometry (TG-FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The adsorption characteristics and capacity was studied at room temperature, the highest CO2 adsorption capacity of 156.6?mg/g-PEI was obtained and the optimal adsorption capacity can reach a maximum value of 54.8?mg/g-adsorbent. The experiment indicated that this kind of adsorbent has a high stability at 80?and PEI impregnated adsorbents showed good reversibility and stability during cyclic adsorption-regeneration tests.
Related JoVE Video
Impact of early tumor shrinkage on clinical outcome in wild-type-KRAS colorectal liver metastases treated with cetuximab.
J. Gastroenterol. Hepatol.
PUBLISHED: 11-04-2014
Show Abstract
Hide Abstract
To evaluate the impact of early tumor shrinkage (ETS) on long-term outcome in patients with wild-type-KRAS unresectable colorectal liver metastases (CLM) receiving cetuximab plus chemotherapy METHODS: 138 patients in a randomized controlled trial (70 in armA received cetuximab plus chemotherapy, 68 in armB received chemotherapy alone), as previously reported (Ye et al, JCO, 2013) were included into this analysis. The cutoff date updated for overall survival (OS) was June 2014. ETS was defined as a ?20% reduction of the longest diameters of the target lesions compared with baseline at the first evaluation (8 weeks). Outcome measures were progression-free survival (PFS) and OS.
Related JoVE Video
Programmable and Multiparameter DNA-based Logic Platform For Cancer Recognition and Targeted Therapy.
J. Am. Chem. Soc.
PUBLISHED: 11-01-2014
Show Abstract
Hide Abstract
The specific inventory of molecules on diseased cell surfaces (e.g., cancer cells) provides clinicians an opportunity for accurate diagnosis and intervention. With the discovery of panels of cancer markers, carrying out analyses of multiple cell-surface markers is conceivable. As a trial to accomplish this, we have recently designed a DNA-based device that is capable of performing autonomous logic-based analysis of 2-or-3 cancer cell-surface markers. Combining the specific target-recognition properties of DNA aptamers with toehold-mediated strand displacement reactions, multi-cellular marker-based cancer analysis can be realized based on modular AND, OR and NOT Boolean logic gates. Specifically, we report here a general approach for assembling these modular logic gates to execute programmable and higher-order profiling of multiple coexisting cell-surface markers, including several found on cancer cells, with the capacity to report a diagnostic signal and/or deliver targeted photodynamic therapy. The success of this strategy demonstrates the potential of DNA nanotechnology in facilitating targeted disease diagnosis and effective therapy.
Related JoVE Video
Phylotranscriptomic analysis of the origin and early diversification of land plants.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 10-29-2014
Show Abstract
Hide Abstract
Reconstructing the origin and evolution of land plants and their algal relatives is a fundamental problem in plant phylogenetics, and is essential for understanding how critical adaptations arose, including the embryo, vascular tissue, seeds, and flowers. Despite advances in molecular systematics, some hypotheses of relationships remain weakly resolved. Inferring deep phylogenies with bouts of rapid diversification can be problematic; however, genome-scale data should significantly increase the number of informative characters for analyses. Recent phylogenomic reconstructions focused on the major divergences of plants have resulted in promising but inconsistent results. One limitation is sparse taxon sampling, likely resulting from the difficulty and cost of data generation. To address this limitation, transcriptome data for 92 streptophyte taxa were generated and analyzed along with 11 published plant genome sequences. Phylogenetic reconstructions were conducted using up to 852 nuclear genes and 1,701,170 aligned sites. Sixty-nine analyses were performed to test the robustness of phylogenetic inferences to permutations of the data matrix or to phylogenetic method, including supermatrix, supertree, and coalescent-based approaches, maximum-likelihood and Bayesian methods, partitioned and unpartitioned analyses, and amino acid versus DNA alignments. Among other results, we find robust support for a sister-group relationship between land plants and one group of streptophyte green algae, the Zygnematophyceae. Strong and robust support for a clade comprising liverworts and mosses is inconsistent with a widely accepted view of early land plant evolution, and suggests that phylogenetic hypotheses used to understand the evolution of fundamental plant traits should be reevaluated.
Related JoVE Video
Simultaneous Synthesis and Assembly of Silver Nanoparticles to Three-Demensional Superstructures for Sensitive Surface-Enhanced Raman Spectroscopy Detection.
ACS Appl Mater Interfaces
PUBLISHED: 10-29-2014
Show Abstract
Hide Abstract
Construction of superstructures with controllable morphologies from NPs is of great scientific and technological importance. A one-step method for simultaneous synthesis and assembly of Ag NPs to three-dimensional (3D) nanoporous superstructures is demonstrated. By varying the adsorption time of Ag precursors, an array of well-defined Ag superstructures with different morphologies are harvested. A "hot spot"-rich substrate for surface-enhanced Raman spectroscopy is established, which exhibits high sensitivity in trace detection of molecules. It is believed that the presented 3D nanoporous Ag superstructures hold great potential for various uses, such as novel multifunctional sensing and monitoring chips or devices.
Related JoVE Video
Easy quantitative assessment of genome editing by sequence trace decomposition.
Nucleic Acids Res.
PUBLISHED: 10-11-2014
Show Abstract
Hide Abstract
The efficacy and the mutation spectrum of genome editing methods can vary substantially depending on the targeted sequence. A simple, quick assay to accurately characterize and quantify the induced mutations is therefore needed. Here we present TIDE, a method for this purpose that requires only a pair of PCR reactions and two standard capillary sequencing runs. The sequence traces are then analyzed by a specially developed decomposition algorithm that identifies the major induced mutations in the projected editing site and accurately determines their frequency in a cell population. This method is cost-effective and quick, and it provides much more detailed information than current enzyme-based assays. An interactive web tool for automated decomposition of the sequence traces is available. TIDE greatly facilitates the testing and rational design of genome editing strategies.
Related JoVE Video
MicroRNA signature in response to nutrient restriction and re-feeding in fast skeletal muscle of grass carp (Ctenopharyngodon idella).
Zool. Res.
PUBLISHED: 10-10-2014
Show Abstract
Hide Abstract
The grass carp (Ctenopharyngodon idella) is one of the most important cultivated fish species in China. Mounting evidences suggests that microRNAs (miRNAs) may be key regulators of skeletal muscle among the grass carp, but the knowledge of the identity of myogenic miRNAs and role of miRNAs during skeletal muscle anabolic state remains limited. In the present study, we choose 8 miRNAs previously reported to act as muscle growth-related miRNAs for fasting-refeeding research. We investigated postprandial changes in the expression of 8 miRNAs following a single satiating meal in grass carp juveniles who had been fasting for one week and found that 7 miRNAs were sharply up-regulated within 1 or 3 h after refeeding, suggesting that they may be promising candidate miRNAs involved in a fast-response signaling system that regulates fish skeletal muscle growth.
Related JoVE Video
Postsynaptic insertion of AMPA receptor onto cortical pyramidal neurons in the anterior cingulate cortex after peripheral nerve injury.
Mol Brain
PUBLISHED: 10-07-2014
Show Abstract
Hide Abstract
Long-term potentiation (LTP) is the key cellular mechanism for physiological learning and pathological chronic pain. Postsynaptic accumulation of AMPA receptor (AMPAR) GluA1 plays an important role for injury-related cortical LTP. However, there is no direct evidence for postsynaptic GluA1 insertion or accumulation after peripheral injury. Here we report nerve injury increased the postsynaptic expression of AMPAR GluA1 in pyramidal neurons in the layer V of the anterior cingulate cortex (ACC), including the corticospinal projecting neurons. Electrophysiological recordings show that potentiation of postsynaptic responses was reversed by Ca2+ permeable AMPAR antagonist NASPM. Finally, behavioral studies show that microinjection of NASPM into the ACC inhibited behavioral sensitization caused by nerve injury. Our findings provide direct evidence that peripheral nerve injury induces postsynaptic GluA1 accumulation in cingulate cortical neurons, and inhibits postsynaptic GluA1 accumulation which may serve as a novel target for treating neuropathic pain.
Related JoVE Video
Monoammonium glycyrrhizate suppresses tumor necrosis factor-? induced chemokine production in HMEC-1 cells, possibly by blocking the translocation of nuclear factor-?B into the nucleus.
Can. J. Physiol. Pharmacol.
PUBLISHED: 10-02-2014
Show Abstract
Hide Abstract
Monoammonim glycyrrhizate (MAG) derived from licorice has been shown to have anti-inflammatory properties. Chemokines are vital inflammatory mediators that are involved with endothelial damage from leukocyte infiltrates in various inflammatory skin diseases. In this study, we investigated the anti-inflammatory effects and mechanisms of MAG on tumor necrosis factor-? (TNF-?) induced chemokine production in a human dermal microvascular endothelial cell line (HMEC-1). HMEC-1 cells were treated with TNF-?, with or without MAG. The results showed that MAG suppressed TNF-?-induced chemokine (including CXCL8, CX3CL1, and CXCL16) mRNA expression in HMEC-1 cells, in a dose-dependent manner, and reduced the secretion of these chemokines in culture supernatant. Moreover, endothelial activation in the presence of MAG blocked the chemotactic activities of TNF-?-stimulated HMEC-1 cell supernatant on the migration of primary neutrophils and primary monocytes. In addition, Western blot and immunofluorescence data revealed that MAG inhibited nuclear translocation of nuclear factor-?B p65 (NF-?B p65). It is the first report to demonstrate that MAG suppresses TNF-?-induced chemokine production in HMEC-1 cells, and that the mechanism may be inhibiting the translocation of NF-?B p65 into the nucleus to prevent the starting of inflammatory signaling pathway. Our results revealed that MAG is a potential anti-inflammatory agent capable of improving inflammatory skin diseases.
Related JoVE Video
Complete mitochondrial genome of the hybrid of Oreochromis niloticus (?)?×?Oreochromis aureus (?).
Mitochondrial DNA
PUBLISHED: 09-27-2014
Show Abstract
Hide Abstract
Abstract In this paper, the complete mitochondrial genome of the hybrid of Oreochromis niloticus (?)?×?Oreochromis aureus (?) was determined using PCR-based method. The mitogenome was 16,663?bp in length, containing the same gene order and an identical number of genes or regions with the other Cichlid fishes, including 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 1 putative control region. The overall composition of the mitogenome was 30.92% C, 27.98% A, 25.54% T, 15.56% G, with a slight AT bias of 53.52% occurs in the hybrid mitogenome. All the protein-coding genes were initiated by typical ATG codon, except for COX1 gene with the initiation codon GTG. Eight genes end with the complete stop codon TAA or TAG, while the COX2, COX3, ND3, ND4 and Cytb genes terminated with an incomplete stop codon T. The complete mitochondrial genome of Oreochromis niloticus (?)?×?Oreochromis aureus (?) may provide important DNA molecular data for further elucidation of evolutionary mechanisms in the hybrid fish of Cichlidae.
Related JoVE Video
Perovskite photovoltaics: a high-efficiency newcomer to the solar cell family.
Nanoscale
PUBLISHED: 09-27-2014
Show Abstract
Hide Abstract
Organometal trihalide perovskite-based light absorbers have attracted great attention due to their excellent photovoltaic properties. The swift developments in the device fabrication techniques have led to the power conversion efficiencies exceeding 17%. In this minireview, we will present the typical characteristics of the materials and device structures, followed by analysing updated understandings on the operational principles of the devices. We will also point out the outstanding issues regarding the materials and devices. Finally, as a high-efficiency newcomer to the solar cell family, the potential impact on the relevant photovoltaics will be discussed.
Related JoVE Video
Abdominal Paracentesis Drainage Ahead of Percutaneous Catheter Drainage Benefits Patients Attacked by Acute Pancreatitis With Fluid Collections: A Retrospective Clinical Cohort Study.
Crit. Care Med.
PUBLISHED: 09-25-2014
Show Abstract
Hide Abstract
The efficacy and safety of ultrasound-guided abdominal paracentesis drainage ahead of percutaneous catheter drainage as the new second step of a step-up approach are evaluated.
Related JoVE Video
High-Performance, Stretchable, Wire-Shaped Supercapacitors.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 09-23-2014
Show Abstract
Hide Abstract
A general approach toward extremely stretchable and highly conductive electrodes was developed. The method involves wrapping a continuous carbon nanotube (CNT) thin film around pre-stretched elastic wires, from which high-performance, stretchable wire-shaped supercapacitors were fabricated. The supercapacitors were made by twisting two such CNT-wrapped elastic wires, pre-coated with poly(vinyl alcohol)/H3 PO4 hydrogel, as the electrolyte and separator. The resultant wire-shaped supercapacitors exhibited an extremely high elasticity of up to 350?% strain with a high device capacitance up to 30.7 F?g(-1) , which is two times that of the state-of-the-art stretchable supercapacitor under only 100?% strain. The wire-shaped structure facilitated the integration of multiple supercapacitors into a single wire device to meet specific energy and power needs for various potential applications. These supercapacitors can be repeatedly stretched from 0 to 200?% strain for hundreds of cycles with no change in performance, thus outperforming all the reported state-of-the-art stretchable electronics.
Related JoVE Video
Aptamer CaCO3 Nanostructures: A Facile, pH-Responsive, Specific Platform for Targeted Anticancer Theranostics.
Chem Asian J
PUBLISHED: 09-23-2014
Show Abstract
Hide Abstract
The application of cancer theranostics depends on the development of multifunctional nanostructured platforms for accurate cell targeting and controlled drug release, imaging, and therapy. Herein, a comprehensive, easily fabricated anticancer theranostic platform with a high drug-loading capacity, termed an aptamer-functionalized calcium carbonate (CaCO3 ) nanostructure (apt-CCN), is reported. Flow cytometry and confocal fluorescence microscopy studies demonstrate that apt-CCNs can specifically bind to target cancer cells, but not to control cells, and that they possess highly efficient internalization to target cancer cells. This smart nanostructure selectively reaches the lysosomes through receptor-mediated endocytosis and is responsive to the relatively low lysosome pH (4.5-5.5), which facilitates the release of doxorubicin. The apt-CCN platform offers targeted and efficient drug transport, as well as target-specific delivery of imaging agents for cancer diagnosis and therapy.
Related JoVE Video
Genetic Variations rs11892031 and rs401681 Are Associated with Bladder Cancer Risk in a Chinese Population.
Int J Mol Sci
PUBLISHED: 09-05-2014
Show Abstract
Hide Abstract
Genome-wide association studies (GWAS) have identified a number of genetic variants associated with risk of bladder cancer in populations of European descent. Here, we assessed association of two of these variants, rs11892031 (2q37.1 region) and rs401681 (5p15.33 region) in a Chinese case-control study, which included 367 bladder cancer cases and 420 controls. We found that the AC genotype of rs11892031 was associated with remarkably decreased risk of bladder cancer (adjusted odds ratio (OR), 0.27; 95% confidence interval (CI), 0.09-0.81; p = 0.019), compared with the AA genotype of rs11892031; and that CT/CC genotypes of rs401681 were associated with significantly increased risk of bladder cancer (adjusted OR, 1.79; 95% CI, 1.10-2.91; p = 0.02), compared with the TT genotype of rs401681. We further conducted stratification analysis to examine the correlation between single nucleotide polymorphism (SNP) rs11892031/rs401681 and tumor grade/stage. Results showed that heterogeneity in ORs of tumor categories was not significant for either rs11892031 or rs401681 (p > 0.05), indicating that the two SNPs seemingly do not associate with tumor grade and stage of bladder cancer in our study population. The present study suggests that the SNPs rs11892031 and rs401681 are associated with bladder cancer risk in a Chinese population. Future analyses will be conducted with more participants recruited in a case-control study.
Related JoVE Video
[Isolation and preparation of an imidazole alkaloid from radix radix of Aconitum pendulum Busch by semi-preparative high-speed counter-current chromatography].
Se Pu
PUBLISHED: 09-05-2014
Show Abstract
Hide Abstract
Aconitum pendulum Busch is rich C19 diterpenoid alkaloids, but there is no report of imidazole alkaloid in Aconitum pendulum Busch. In this study, an imidazole alkaloid named 1H-imidazole-2-carboxylic acid, butyl ester (ICABE) was successfully separated from Aconitum pendulum Busch with semi-preparative high-speed counter-current chromatography (HSCCC). The partition coefficient was measured by HPLC to select the solvent systems for ICABE separation by HSCCC. The separation was performed with a two-phase solvent system composed of n-hexane-chloroform-ethanol-water (10:1 : 13:2, v/v/v/v). The upper phase was used as the stationary phase and the lower phase as the mobile phase. It was operated at a flow rate of 1.8 mL/min. The apparatus was rotated at 850 r/min, and the detection wavelength was set at 230 nm. Under the selected conditions, a high efficiency separation of HSCCC was achieved, and 7.5 mg of ICABE was obtained from 100 mg of the crude sample of Aconitum pendulum in one-step separation within 350 min. The HPLC analysis showed that the purity of the compound was over 98%. The chemical structure was confirmed by UV, 1H-NMR and 13C-NMR. The established method is simple, highly efficient and suitable for large scale separation of ICABE from radix of Aconitum pendulum Busch.
Related JoVE Video
Design, synthesis and herbicidal activity of novel quinazoline-2,4-diones as 4-hydroxyphenylpyruvate dioxygenase inhibitors.
Pest Manag. Sci.
PUBLISHED: 09-03-2014
Show Abstract
Hide Abstract
4-Hydroxyphenylpyruvate dioxygenase (HPPD) (EC 1.13.11.27) has been identified as one of the most promising target sites for herbicide discovery. To discover novel HPPD inhibitors with high herbicidal activity and improved crop selectivity, a series of novel triketone-containing quinazoline-2,4-dione derivatives possessing a variety of substituents at the N-1 position of the quinazoline-2,4-dione ring were designed and synthesised.
Related JoVE Video
Janus polymer/carbon nanotube hybrid membranes for oil/water separation.
ACS Appl Mater Interfaces
PUBLISHED: 09-02-2014
Show Abstract
Hide Abstract
A robust and simple method is provided to fabricate Janus polymer/carbon nanotube (CNT) hybrid membranes for oil/water separation. Starting from CNT membranes formed by dispensing, hydrophobic poly(styrene) (PS) and hydrophilic poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) were grated from different sides of the photoactive CNT membranes via self-initiated photografting and photopolymerization (SIPGP) to achieve Janus polymer/CNTs hybrid membranes. The obtained membranes have excellent oil/water selectivity in the removal of oil from water. Moreover, they can effectively separate both surfactant-stabilized oil-in-water and water-in-oil emulsions because of the anisotropic wettability of the membranes.
Related JoVE Video
Facile surface functionalization of hydrophobic magnetic nanoparticles.
J. Am. Chem. Soc.
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
Nonpolar phase synthesized hydrophobic nanocrystals show attractive properties and have demonstrated prominent potential in biomedical applications. However, the preparation of biocompatible nanocrystals is made difficult by the presence of hydrophobic surfactant stabilizer on their surfaces. To address this limitation, we have developed a facile, high efficiency, single-phase and low-cost method to convert hydrophobic magnetic nanoparticles (MNPs) to an aqueous phase using tetrahydrofuran, NaOH and 3,4-dihydroxyhydrocinnamic acid without any complicated organic synthesis. The as-transferred hydrophilic MNPs are water-soluble over a wide pH range (pH = 3-12), and the solubility is pH-controllable. Furthermore, the as-transferred MNPs with carboxylate can be readily adapted with further surface functionalization, varying from small molecule dyes to oligonucleotides and enzymes. Finally, the strategy developed here can easily be extended to other types of hydrophobic nanoparticles to facilitate biomedical applications of nanomaterials.
Related JoVE Video
Decrease of 5-hydroxymethylcytosine in rat liver with subchronic exposure to genotoxic carcinogens riddelliine and aristolochic acid.
Mol. Carcinog.
PUBLISHED: 08-23-2014
Show Abstract
Hide Abstract
The level of 5-hydroxymethylcytosine (5-hmC) converted by ten-eleven translocation (TET) family is decreased in cancers. However, whether 5-hmC level is perturbed in early stages of carcinogenesis caused by genotoxic carcinogens is not defined. 5-hmC levels and TET2 expression were measured in liver of rats treated with genotoxic carcinogens, riddelliine, or aristolochic acid. Levels of 5-hmC and TET2 expression decreased in the liver of the carcinogens-treated rats. Loss of 5-hmC correlates well with documented induction of genetic mutations by the carcinogens, suggesting that TET2-mediated 5-hydroxymethylation plays an epigenetic role in early state of carcinogenesis. © 2014 Wiley Periodicals, Inc.
Related JoVE Video
A comparative study on the levels of serum cytokines and cortisol among post-traumatic stress disorder patients of Li and Han ethnicities in Hainan.
Chin. Med. J.
PUBLISHED: 08-23-2014
Show Abstract
Hide Abstract
Post-traumatic stress disorder (PTSD) is a mental disorder with delayed or chronic onset caused by unusual, threatening, or disastrous psychological trauma, and it is an important manifestation of post-disaster mental and behavioral disorders. Studies have shown that IL-6 is a cytokine associated with PTSD occurrence. This study aimed to explore the role of cytokine and ethnicity in the pathogenesis of PTSD by examining levels of serum cytokines IL-2, IL-6, IL-8, TNF-?, and cortisol in PTSD patients of Li and Han ethnic groups.
Related JoVE Video
[Characteristics of soil organic carbon mineralization at different temperatures in paddy soils under long-term fertilization].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 08-19-2014
Show Abstract
Hide Abstract
Dynamics of soil organic carbon mineralization affected by long-term fertilizations and temperature in relation to different soil carbon fractions were investigated in paddy soils. Soil samples were collected from the plough layer of 3 long-term national experimental sites in Xinhua, Ningxiang and Taojiang counties of Hunan Province. Mineralization of soil organic C was estimated by 33-day aerobic incubation at different temperatures of 10, 20 and 30 degrees C. The results showed that the rates of CO2 production were higher during the earlier phase (0-13 d) in all treatments, and then decreased according to a logarithm function. Higher incubation temperature strengthened C mineralization in the different treatments. The quantities of cumulative CO2 production in NPK with manure or straw treatments were greater than in inorganic fertilizers treatments. The Q10 values in the different soil treatments ranged from 1.01-1.53. There were significantly positive correlations between the Q10 values and soil total organic carbon (TOC), easy oxidation organic carbon (EOOC), humic acid carbon (C(HA)), fulvic acid carbon (CFA). The cumulative amount of mineralized C was significantly positively correlated with microbial biomass carbon (MBC) at 10 and 20 degrees C, but not significantly at 30 degrees C. Significant correlations were found between the cumulative amount of mineralized C and different soil carbon fractions and C(HA)/C(FA). The correlations of differ- ent soil carbon fractions with the ratio of cumulative mineralized C to TOC were negatively correlated at 10 degrees C, but not significantly at 20 and 30 degrees C. These results suggested that the application of NPK with manure or straw would be helpful to increase the sequestration of C in paddy soils and reduce its contribution of CO2 release in the atmosphere.
Related JoVE Video
Influence of carotid artery stenting on cognition of elderly patients with severe stenosis of the internal carotid artery.
Med. Sci. Monit.
PUBLISHED: 08-17-2014
Show Abstract
Hide Abstract
The aim of this study was to investigate the influence of carotid artery stenting (CAS) on the cognition and quality of life of elderly patients with severe stenosis of the internal carotid artery.
Related JoVE Video
Self-healable macro-/microscopic shape memory hydrogels based on supramolecular interactions.
Chem. Commun. (Camb.)
PUBLISHED: 08-16-2014
Show Abstract
Hide Abstract
A simple strategy is provided to construct novel supramolecular hydrogels with both self-healing and shape memory properties. Starting from achieving self-healable hydrogel based on the dynamic interactions of phenylboronic acid modified sodium alginate (Alg-PBA) and poly(vinyl alcohol) (PVA), further formation of a complex of alginate with Ca(2+) renders this hydrogel with the capability of shape memory at the macro-/microscopic scales.
Related JoVE Video
Association between BRCA1 rs799917 polymorphism and breast cancer risk: A meta-analysis of 19,878 subjects.
Biomed. Pharmacother.
PUBLISHED: 08-14-2014
Show Abstract
Hide Abstract
Studies investigating the association between the BRCA1 rs799917 polymorphism and breast cancer risk have reported controversial results. In order to derive a more precise estimation of the relationship, we performed a comprehensive meta-analysis. A total of 8 articles comprising 19,878 subjects were included in this meta-analysis. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated by Stata 11 software. Heterogeneity tests were conducted by Q test with I(2) value, and publication bias assessment was performed by Begg's funnel plot and Egger's test. The pooled results did not show any sufficient evidence approving the association between the BRCA1 rs799917 polymorphism and breast cancer risk in total population (T vs C: OR=1.01, 95% CI=0.97-1.06; TT vs CC: OR=1.03, 95% CI=0.93-1.13; CT vs CC: OR=1.04, 95% CI=0.92-1.16; TT+CT vs CC: OR=1.04, 95% CI=0.94-1.15; TT vs CT+CC: OR=1.03, 95% CI=0.94-1.12). In the further subgroup analyses, no significant associations were found in any comparison models according to ethnicity and source of controls. No publication bias was observed in this meta-analysis. In summary, based on the overall results, this meta-analysis strongly suggests that the BRCA1 rs799917 polymorphism is not associated with breast cancer risk.
Related JoVE Video
Association between cytosolic serine hydroxymethyltransferase (SHMT1) gene polymorphism and cancer risk: a meta-analysis.
Biomed. Pharmacother.
PUBLISHED: 08-14-2014
Show Abstract
Hide Abstract
The serine hydroxymethyltransferase (SHMT1) is the key enzyme in the folate metabolic pathway to provide one-carbon unit that plays an important role in biosynthesis. Abnormal biosynthesis involved in DNA synthesis and methylation can lead to activation of oncogenes and inactivation of tumor suppressor genes. And the abnormal biosynthesis is closely related to a variety of common tumors' occurrence and development. A SNP in SHMT1 C1420T may effect the procession of biosynthesis and finally influence cancer occurrence.
Related JoVE Video
Hybrid ZnO Nanorod-Polymer Brush Hierarchically Nanostructured Substrate for Sensitive Antibody Microarrays.
Adv. Mater. Weinheim
PUBLISHED: 08-13-2014
Show Abstract
Hide Abstract
A hierarchically nanostructured organic-inorganic hybrid substrate comprising randomly oriented ZnO nanorods on glass slide with coaxially tethered dense polymer brush, POEGMA-co-GMA is reported for highly sensitive antibody microassay, achieving excellent detection specificity, and superior detection limit of as low as 100 fg mL(-1) for biomarkers in human serum within 1 h assay time.
Related JoVE Video
Adenylyl cyclase subtype 1 is essential for late-phase long term potentiation and spatial propagation of synaptic responses in the anterior cingulate cortex of adult mice.
Mol Pain
PUBLISHED: 08-13-2014
Show Abstract
Hide Abstract
Long-term potentiation (LTP) is a key cellular mechanism for pathological pain in the central nervous system. LTP contains at least two different phases: early-phase LTP (E-LTP) and late-phase LTP (L-LTP). Among several major cortical areas, the anterior cingulate cortex (ACC) is a critical brain region for pain perception and its related emotional changes. Periphery tissue or nerve injuries cause LTP of excitatory synaptic transmission in the ACC. Our previous studies have demonstrated that genetic deletion of calcium-stimulated adenylyl cyclase 1 (AC1) or pharmacological application of a selective AC1 inhibitor NB001 blocked E-LTP in the ACC. However, the effect of AC1 on L-LTP, which requires new protein synthesis and is important for the process of chronic pain, has not been investigated. Here we tested the effects of NB001 on the ACC L-LTP and found that bath application of NB001 (0.1 ?M) totally blocked the induction of L-LTP and recruitment of cortical circuitry without affecting basal excitatory transmission. In contrast, gabapentin, a widely used analgesic drug for neuropathic pain, did not block the induction of L-LTP and circuitry recruitment even at a high concentration (100 ?M). Gabapentin non-selectively decreased basal synaptic transmission. Our results provide strong evidence that the selective AC1 inhibitor NB001 can be used to inhibit pain-related cortical L-LTP without affecting basal synaptic transmission. It also provides basic mechanisms for possible side effects of gabapentin in the central nervous system and its ineffectiveness in some patients with neuropathic pain.
Related JoVE Video
Improved poly(3-hydroxybutyrate) production in Escherichia coli by inactivation of cytochrome bd-II oxidase or/and NDH-II dehydrogenase in low efficient respiratory chains.
J. Biotechnol.
PUBLISHED: 08-13-2014
Show Abstract
Hide Abstract
In order to redirect more carbon flux from TCA cycle into poly(3-hydroxybutyrate) (PHB) biosynthesis pathway via increasing respiratory efficiency, appB and ndh genes encoding cytochrome bd-II oxidase and NDH-II dehydrogenase were inactivated in Escherichia coli JM109/pBHR68. All appB or/and ndh knockout strains exhibited significantly increased PHB accumulation accompanying with increased NAD(P)H/NAD(P)(+) ratio and intracellular acetyl-CoA pool. Among them, the ?ndh strain could accumulate up to 6.16g/L PHB from 20g/L glucose and 3.5g/L PHB from 20g/L xylose, respectively, a 1.76-fold and 3.43-fold increase compared to the wild-type control. The PHB production of this strain reached 28.23g/L in a 5-L fermentor study, which was 2.70-fold as much as that of the wild-type control. These results indicated that inactivating the cytochrome bd-II oxidase or/and NDH-II dehydrogenase of the aerobic respiratory chain is a simple and effective strategy to improve PHB biosynthesis in E. coli. To date, this is the first time to improve PHB production by inactivation of cytochrome bd-II oxidase or/and NDH-II dehydrogenase in low efficient respiratory chains.
Related JoVE Video
Effect of different sulfides on cadmium distribution during sludge combustion based on experimental and thermodynamic calculation approaches.
Environ Sci Pollut Res Int
PUBLISHED: 08-13-2014
Show Abstract
Hide Abstract
The effects of sulfur compounds on the migration of a semi-volatile heavy metal (cadmium) during sludge incineration were investigated with two methods, i.e., experiments in a tubular furnace reactor and thermodynamic equilibrium calculations. The representative typical sludge with and without the addition of sulfur compounds was incinerated at 850 °C. The partitioning of Cd among the solid phase (bottom ash) and gas phase (fly ash and flue gas) was quantified. The results indicate that sulfur compounds in the elemental form and a reduced state could stabilize Cd in the form of CdS, aluminosilicate minerals, and polymetallic sulfides, whereas sulfur in the oxidized forms slightly increases Cd volatilization during incineration. For Cd solidification points, the inhibition effect on the volatilization of Cd is as follows: S > Na2SO4 > Na2S. Chemical equilibrium calculations indicate that sulfur binds with Cd and alters Cd speciation at low temperatures (<950 K). Furthermore, SiO2- and Al2O3-containing minerals can function as sorbents stabilizing Cd as condensed phase solids (CdSiO4 and CdAl2O4) according to the results of equilibrium calculations. These findings provide useful information for understanding the partitioning of Cd and thus facilitate the development of strategies to control Cd volatilization during sludge incineration.
Related JoVE Video
Imaging without fluorescence: nonlinear optical microscopy for quantitative cellular imaging.
Anal. Chem.
PUBLISHED: 08-12-2014
Show Abstract
Hide Abstract
Quantitative single-cell analysis enables the characterization of cellular systems with a level of detail that cannot be achieved with ensemble measurement. In this Feature we explore quantitative cellular imaging applications with nonlinear microscopy techniques. We first offer an introductory tutorial on nonlinear optical processes and then survey a range of techniques that have proven to be useful for quantitative live cell imaging without fluorescent labels.
Related JoVE Video
Tissue-specific microRNA responses in rats treated with mutagenic and carcinogenic doses of aristolochic acid.
Mutagenesis
PUBLISHED: 08-08-2014
Show Abstract
Hide Abstract
Aristolochic acid (AA) is an active component in herbal drugs derived from the Aristolochia species. Although these drugs have been used since antiquity, AA is both genotoxic and carcinogenic in animals and humans, resulting in kidney tumours in rats and upper urinary tract tumours in humans. In the present study, we conducted microarray analysis of microRNA (miRNA) expression in tissues from transgenic Big Blue rats that were treated for 12 weeks with 0.1-10mg/kg AA, using a protocol that previous studies indicate eventually results in kidney tumours and mutations in kidney and liver. Global analysis of miRNA expression of rats treated with 10 mg/kg AA indicated that 19 miRNAs were significantly dysregulated in the kidney, with most of the miRNAs related to carcinogenesis. Only one miRNA, miR-34a (a tumour suppressor), was differentially expressed in the liver. The expression of the two most responsive kidney miRNAs (miR-21, an oncomiR and miR-34a) was further examined in the kidney, liver and testis of rats exposed to 0, 0.1, 1.0 and 10mg/kg AA. Expression of miR-21 was up-regulated in the kidney only, while miR-34a was dose-dependently up-regulated in both the kidney and liver; the expression of miR-21 and miR-34a was unaltered by the AA treatment in the testis. Analysis of cII mutations in the testis of treated rats also was negative. Our results indicate that AA treatment of rats produced dysregulation of a large number of miRNAs in the tumour target tissue and that the up-regulation of miR-21 correlated with the carcinogenicity of AA while the up-regulation of miR-34a correlated with its mutagenicity.
Related JoVE Video
Transient absorption microscopy of gold nanorods as spectrally orthogonal labels in live cells.
Nanoscale
PUBLISHED: 08-07-2014
Show Abstract
Hide Abstract
Gold nanorods (AuNRs) have shown great potential as bio-compatible imaging probes in various biological applications. Probing nanomaterials in live cells is essential to reveal the interaction between them. In this study, we used a transient absorption microscope to selectively image AuNRs in live cells. The transient absorption signals were monitored through lock-in amplification. This provides a new way of observing AuNRs with no interference from background autofluorescence.
Related JoVE Video
Direct validation of the restriction of intramolecular rotation hypothesis via the synthesis of novel ortho-methyl substituted tetraphenylethenes and their application in cell imaging.
Chem. Commun. (Camb.)
PUBLISHED: 08-07-2014
Show Abstract
Hide Abstract
We demonstrate a novel synthetic approach to ortho-methyl substituted tetraphenylethene materials, which can be utilised for directly validating the restriction of intramolecular rotation hypothesis as the basic mechanism of aggregation-induced emission phenomenon and cell imaging.
Related JoVE Video
Suprapubic single incision laparoscopic appendectomy.
J. Surg. Res.
PUBLISHED: 08-04-2014
Show Abstract
Hide Abstract
The single incision method through the umbilicus is commonly used for laparoscopic appendectomy. To obtain a better cosmetic outcome and less surgical complexity, we have designed a new single-incision laparoscopic appendectomy technique performed above the pubic symphysis.
Related JoVE Video
The use of poly(methacrylic acid) nanogel to control the release of amoxycillin with lower cytotoxicity.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 08-02-2014
Show Abstract
Hide Abstract
In order to control the release of amoxycillin (AM) with lower cytotoxicity and higher activity, ethylene glycol dimethacrylate was used as the cross-linker, and a series of poly(methacrylic acid) (PMAA) nanogels were prepared to load the AM. Then, the morphology, size, in vitro release property, long-term antibacterial performance, cytotoxicity, stability and activity of this novel AM/PMAA nanogel were investigated. The results showed that the AM/PMAA nanogel sustainably released AM with long-term antibacterial activity. Moreover, the AM/PMAA nanogel could improve the stability of AM. More importantly, this AM/PMAA nanogel showed slighter cytotoxicity than AM alone, suggesting that the AM/PMAA nanogel was a more useful dosage form than AM for infectious diseases.
Related JoVE Video
Development of a markerless gene replacement system in Corynebacterium glutamicum using upp as a counter-selection marker.
Biotechnol. Lett.
PUBLISHED: 07-23-2014
Show Abstract
Hide Abstract
Corynebacterium glutamicum is well-established for industrial and biotechnological applications. However, its genetic manipulation has generally lagged behind traditional genetic models. In this study, a counter-selectable marker gene upp was firstly confirmed to be more efficient than traditional sacB. Furthermore, a markerless gene replacement system was developed by combining upp with double-strand break repair caused by the exogenous endonuclease I-SceI. Finally, genetic modification using a dsDNA PCR fragment was carried out with the expression of recombinase/exonuclease RecE/RecT. Our results show that the genetic modification system allows precise and markerless gene replacement without altering the chromosome, with a simplified screening procedure to generate its modification.
Related JoVE Video
Preparation of two flavonoid glycosides with unique structures from barley seedlings by membrane separation technology and preparative high-performance liquid chromatography.
J Sep Sci
PUBLISHED: 07-23-2014
Show Abstract
Hide Abstract
Barley seedlings are rich in flavones that can have positive effects on people with antihypoxia and antifatigue. Lutonarin and saponarin are two major flavonoid glycosides that have unique structures in barley seedlings. This study presents a new approach for the preparation of lutonarin and saponarin from barely seedlings by membrane separation technology and preparative high-performance liquid chromatography. Preparative conditions of these two flavonoid glycosides by membrane separation technology were studied using response surface methodology. Under the optimized conditions, the total contents of these two flavonoid glycosides amounts to 17.0%.
Related JoVE Video
Purification and X-ray crystallographic analysis of 7-keto-8-aminopelargonic acid (KAPA) synthase from Mycobacterium smegmatis.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 07-17-2014
Show Abstract
Hide Abstract
7-Keto-8-aminopelargonic acid synthase (KAPA synthase; BioF) is an essential enzyme for mycobacterial growth that catalyses the first committed step in the biotin-synthesis pathway. It is a pyridoxal 5'-phosphate (PLP)-dependent enzyme and is a potential drug target. Here, the cloning, expression, purification and crystallization of KAPA synthase from Mycobacterium smegmatis (MsBioF) and the characterization of MsBioF crystals using X-ray diffraction are described. The crystals diffracted to 2.3?Å resolution and belonged to the monoclinic space group P21, with unit-cell parameters a = 70.88, b = 91.68, c = 109.84?Å, ? = 97.8°. According to the molecular weight of MsBioF, the unit-cell parameters and the self-rotation function map, four molecules are present in each asymmetric unit with a VM value of 2.06?Å(3)?Da(-1) and a solvent content of 40.20%.
Related JoVE Video
Increased Plasma DPP4 Activity Is Predictive of Prediabetes and Type 2 Diabetes Onset in Chinese Over a Four-Year Period: Result From the China National Diabetes and Metabolic Disorders Study.
J. Clin. Endocrinol. Metab.
PUBLISHED: 07-16-2014
Show Abstract
Hide Abstract
The significance of associations between prediabetes, type 2 diabetes, and dipeptidyl peptidase-4 (DPP4) activity in a Chinese population is not clear.
Related JoVE Video
FDG PET-CT combined with TBNA for the diagnosis of atypical relapsing polychondritis: report of 2 cases and a literature review.
J Thorac Dis
PUBLISHED: 06-27-2014
Show Abstract
Hide Abstract
To explore the value of (18)F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) combined with transbronchial needle aspiration (TBNA) in diagnosing atypical relapsing polychondritis (RP).
Related JoVE Video
Dielectrophoresis for Bioparticle Manipulation.
Int J Mol Sci
PUBLISHED: 06-24-2014
Show Abstract
Hide Abstract
As an ideal method to manipulate biological particles, the dielectrophoresis (DEP) technique has been widely used in clinical diagnosis, disease treatment, drug development, immunoassays, cell sorting, etc. This review summarizes the research in the field of bioparticle manipulation based on DEP techniques. Firstly, the basic principle of DEP and its classical theories are introduced in brief; Secondly, a detailed introduction on the DEP technique used for bioparticle manipulation is presented, in which the applications are classified into five fields: capturing bioparticles to specific regions, focusing bioparticles in the sample, characterizing biomolecular interaction and detecting microorganism, pairing cells for electrofusion and separating different kinds of bioparticles; Thirdly, the effect of DEP on bioparticle viability is analyzed; Finally, the DEP techniques are summarized and future trends in bioparticle manipulation are suggested.
Related JoVE Video
Sirt3 attenuates hydrogen peroxide-induced oxidative stress through the preservation of mitochondrial function in HT22 cells.
Int. J. Mol. Med.
PUBLISHED: 05-24-2014
Show Abstract
Hide Abstract
Sirtuins (Sirt) are a family of phylogenetically conserved nicotinamide adenine nucleotide (NAD(+))-dependent protein deacetylases, among which Sirt3 resides primarily in the mitochondria and serves as a stress responsive deacetylase, playing a role in protecting cells from damage under stress conditions. The present study aimed to investigate the role of Sirt3 in hydrogen peroxide (H(2)O(2))-induced oxidative neuronal injury in HT22 mouse hippocampal cells. Treatment with H(2)O(2) increased the expression of Sirt3 in a dose- and time-dependent manner, and the knockdown of Sirt3 using specific small interfering RNA (siRNA) exacerbated the H(2)O(2)-induced neuronal injury. The overexpression of Sirt3 induced by lentiviral transfection significantly reduced the generation of reactive oxygen species (ROS) and lipid peroxidation following injury, whereas the activities of endogenous antioxidant enzymes were not affected. Further experiments revealed that the H(2)O(2)-induced inhibition of mitochondrial complex activity and adenosine triphosphate (ATP) synthesis, the decrease in mitochondrial Ca(2+) buffering capacity and mitochondrial swelling were all partly reversed by Sirt3. Furthermore, the overexpression of Sirt3 attenuated the release of cytochrome c, the increase in the Bax/Bcl-2 ratio, as well as caspase-9/caspase-3 activity induced by H(2)O(2), and eventually inhibited apoptotic neuronal cell death. These results suggest that Sirt3 acts as a prosurvival factor, playing an essential role in protecting HT22 cells under H(2)O(2)-induced oxidative stress, possibly by inhibiting ROS accumulation and the activation of the mitochondrial apoptotic pathway.
Related JoVE Video
Netrin-1 with stem cells promote angiogenesis in limb ischemic rats.
J. Surg. Res.
PUBLISHED: 05-14-2014
Show Abstract
Hide Abstract
Recent findings have elucidated that netrin-1 has ability of promoting angiogenesis besides the functions in nervous system. Autologous mesenchymal stem cells (MSCs) transplantation is now proved to be an effective method to treat peripheral arterial disease. However there are still many patients who cannot complete full treatments. Therefore it is necessary to improve the effectiveness. This study estimated the curative effects in chronic limb ischemia when MSCs allied with netrin-1.
Related JoVE Video
Metabolic engineering of Escherichia coli for the production of riboflavin.
Microb. Cell Fact.
PUBLISHED: 05-14-2014
Show Abstract
Hide Abstract
Riboflavin (vitamin B2), the precursor of the flavin cofactors flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), is used commercially as an animal feed supplement and food colorant. E. coli is a robust host for various genetic manipulations and has been employed for efficient production of biofuels, polymers, amino acids, and bulk chemicals. Thus, the aim of this study was to understand the metabolic capacity of E. coli for the riboflavin production by modification of central metabolism, riboflavin biosynthesis pathway and optimization of the fermentation conditions.
Related JoVE Video
Endoscopic retrieval of an 18-cm long chopstick embedded for ten months post-automutilation in the esophagus of a patient with psychosis.
World J Gastrointest Endosc
PUBLISHED: 05-08-2014
Show Abstract
Hide Abstract
Foreign body ingestion is an emergency or acute situation that commonly occurs in children or adults and involves the ingestion of one or more objects. Moreover, once the discovery of swallowed foreign bodies has been made, families are typically very anxious to have the patient see a doctor. If the foreign object becomes embedded in the digestive tract, it must be removed; in emergencies, this is done by endoscopy or surgery. This case report presents the successful endoscopic retrieval of a chopstick with both sides embedded 4 cm into the esophageal wall for > 10 mo in a male patient following automutilation in an attempt to be released from a psychiatric hospital. Hot hemostatic forceps were used to open the distal esophageal mucosa in which the chopstick was embedded. The procedure was performed under intravenous general anesthesia and took approximately 7 h.
Related JoVE Video
PDGFR-?-activated ACK1-AKT Signaling Promotes Glioma Tumorigenesis.
Int. J. Cancer
PUBLISHED: 04-29-2014
Show Abstract
Hide Abstract
Aberrant PDGF-PDGFR signaling and its effects on downstream effectors have been implicated in glioma development. A crucial AKT regulator, ACK1 (TNK2) has been shown to be a downstream mediator of PDGF signaling; however, the exact underlying mechanisms in gliomas remain elusive. Here, we report that in glioma cells, PDGFR-? activation enhanced the interaction between ACK1 and AKT, resulting in AKT activation. PDGF treatment consistently promoted the formation of complexes containing PDGFR-? and ACK1. Mutational analysis suggested that Y635 of ACK1 is a PDGFR-? phosphorylation site and that the ACK1 Y635F mutant abrogated the sequential activation of AKT. Moreover, PDK1 interacted with ACK1 during PDGF stimulation, which is required for the binding of ACK1 to PDGFR-?. Further mutational analysis showed that T325 of ACK1 was crucial for the ACK1 and PDK1 interaction. ACK1 Y635F or T325A mutants abolished PDGFR-?-induced AKT activation, the subsequent nuclear translocation of ?-catenin and the expression of cyclin D1. Glioma cell cycle progression, proliferation and tumorigenesis were accordingly blocked by ACK1 Y635F or T325A. In glioblastoma multiforme samples from 51 patients, increased ACK1 tyrosine phosphorylation correlated with upregulated PDGFR-? activity and AKT activation. Taken together, our data demonstrate that ACK1 plays a pivotal role in PDGF-PDGFR-induced AKT signaling in glioma tumorigenesis. This knowledge contributes to our understanding of glioma progression and may facilitate the identification of novel therapeutic targets for future glioma treatment.
Related JoVE Video
Sirt3 protects cortical neurons against oxidative stress via regulating mitochondrial Ca2+ and mitochondrial biogenesis.
Int J Mol Sci
PUBLISHED: 04-27-2014
Show Abstract
Hide Abstract
Oxidative stress is a well-established event in the pathology of several neurobiological diseases. Sirt3 is a nicotinamide adenine nucleotide (NAD+)-dependent protein deacetylase that regulates mitochondrial function and metabolism in response to caloric restriction and stress. This study aims to investigate the role of Sirt3 in H2O2 induced oxidative neuronal injury in primary cultured rat cortical neurons. We found that H2O2 treatment significantly increased the expression of Sirt3 in a time-dependent manner at both mRNA and protein levels. Knockdown of Sirt3 with a specific small interfering RNA (siRNA) exacerbated H2O2-induced neuronal injury, whereas overexpression of Sirt3 by lentivirus transfection inhibited H2O2-induced neuronal damage reduced the generation of reactive oxygen species (ROS), and increased the activities of endogenous antioxidant enzymes. In addition, the intra-mitochondrial Ca2+ overload, but not cytosolic Ca2+ increase after H2O2 treatment, was strongly attenuated after Sirt3 overexpression. Overexpression of Sirt3 also increased the content of mitochondrial DNA (mtDNA) and the expression of mitochondrial biogenesis related transcription factors. All these results suggest that Sirt3 acts as a prosurvival factor playing an essential role to protect cortical neurons under H2O2 induced oxidative stress, possibly through regulating mitochondrial Ca2+ homeostasis and mitochondrial biogenesis.
Related JoVE Video
Deregulation of purine pathway in Bacillus subtilis and its use in riboflavin biosynthesis.
Microb. Cell Fact.
PUBLISHED: 04-14-2014
Show Abstract
Hide Abstract
Purine nucleotides are essential metabolites for living organisms because they are involved in many important processes, such as nucleic acid synthesis, energy supply, and biosynthesis of several amino acids and riboflavin. Owing to the pivotal roles of purines in cell physiology, the pool of intracellular purine nucleotides must be maintained under strict control, and hence the de novo purine biosynthetic pathway is tightly regulated by transcription repression and inhibition mechanism. Deregulation of purine pathway is essential for this pathway engineering in Bacillus subtilis.
Related JoVE Video
Terahertz pulsed spectroscopy of paraffin-embedded brain glioma.
J Biomed Opt
PUBLISHED: 04-11-2014
Show Abstract
Hide Abstract
The refractive indices, absorption coefficients, and complex dielectric constants of paraffin-embedded brain glioma and normal brain tissues have been measured by a terahertz time-domain spectroscopy (THz-TDS) system in the 0.2- to 2.0-THz range. The spectral differences between gliomas and normal brain tissues were obtained. Compared with normal brain tissue, our results indicate that paraffin-embedded brain gliomas have a higher refractive index, absorption coefficient, and dielectric constant. Based on these results, the best THz frequencies for different methods of paraffin-embedded brain glioma imaging, such as intensity imaging, coherent imaging with continuum THz sources, and THz pulsed imaging with short-pulsed THz sources, are analyzed.
Related JoVE Video
Origin of a novel regulatory module by duplication and degeneration of an ancient plant transcription factor.
Mol. Phylogenet. Evol.
PUBLISHED: 04-04-2014
Show Abstract
Hide Abstract
It is commonly believed that gene duplications provide the raw material for morphological evolution. Both the number of genes and size of gene families have increased during the diversification of land plants. Several small proteins that regulate transcription factors have recently been identified in plants, including the LITTLE ZIPPER (ZPR) proteins. ZPRs are post-translational negative regulators, via heterodimerization, of class III Homeodomain Leucine Zipper (C3HDZ) proteins that play a key role in directing plant form and growth. We show that ZPR genes originated as a duplication of a C3HDZ transcription factor paralog in the common ancestor of euphyllophytes (ferns and seed plants). The ZPRs evolved by degenerative mutations resulting in loss all of the C3HDZ functional domains, except the leucine zipper that modulates dimerization. ZPRs represent a novel regulatory module of the C3HDZ network unique to the euphyllophyte lineage, and their origin correlates to a period of rapid morphological changes and increased complexity in land plants. The origin of the ZPRs illustrates the significance of gene duplications in creating developmental complexity during land plant evolution that likely led to morphological evolution.
Related JoVE Video
Path planning method for UUV homing and docking in movement disorders environment.
ScientificWorldJournal
PUBLISHED: 03-23-2014
Show Abstract
Hide Abstract
Path planning method for unmanned underwater vehicles (UUV) homing and docking in movement disorders environment is proposed in this paper. Firstly, cost function is proposed for path planning. Then, a novel particle swarm optimization (NPSO) is proposed and applied to find the waypoint with minimum value of cost function. Then, a strategy for UUV enters into the mother vessel with a fixed angle being proposed. Finally, the test function is introduced to analyze the performance of NPSO and compare with basic particle swarm optimization (BPSO), inertia weight particle swarm optimization (LWPSO, EPSO), and time-varying acceleration coefficient (TVAC). It has turned out that, for unimodal functions, NPSO performed better searching accuracy and stability than other algorithms, and, for multimodal functions, the performance of NPSO is similar to TVAC. Then, the simulation of UUV path planning is presented, and it showed that, with the strategy proposed in this paper, UUV can dodge obstacles and threats, and search for the efficiency path.
Related JoVE Video
Morphology modulation of SrTiO3/TiO2 heterostructures for enhanced photoelectrochemical performance.
J Colloid Interface Sci
PUBLISHED: 02-05-2014
Show Abstract
Hide Abstract
Design and fabrication of nanoscale semiconductors with regulatable morphology or structure has attracted tremendous interest due to the dependency relationship between properties and architectures. Two types of SrTiO3/TiO2 nanocomposites with different morphologies and structures have been fabricated by controlling the kinetics of hydrothermal reactions. One is TiO2 nanotube arrays densely wrapped by SrTiO3 film and the other is SrTiO3 nanospheres distributed on the top region of TiO2 nanotube arrays, which has been firstly fabricated. It has been found that the photoelectrochemical performances of these heterostructures are crucially dominated by their architectures. Heterostructured SrTiO3/TiO2 nanotube arrays were fabricated by traditional method in the absence of NaOH and they exhibited higher photoelectrochemical performance than pure TiO2 nanotube arrays. However, the compact SrTiO3 coating film on the sidewalls of TiO2 nanotube arrays could inevitably destroy the tubular structures of TiO2 and thus go against the vectorial transport of electrons. Interestingly, when excess NaOH was added into the growth solution, SrTiO3 nanospheres would be rationally grafted on the top of TiO2 nanotube arrays, which could preserve the tubular structures of TiO2, and thus further improve the photoelectrochemical performance.
Related JoVE Video
TNF-like ligand 1A is associated with the pathogenesis of psoriasis vulgaris and contributes to IL-17 production in PBMCs.
Arch. Dermatol. Res.
PUBLISHED: 01-28-2014
Show Abstract
Hide Abstract
TNF-like ligand 1A (TL1A), a newly identified member of the TNF superfamily, has been proved as an important mediator of inflammation and critically involved in the pathogenesis of rheumatoid arthritis and several other autoimmune diseases. The aim of our study was to determine the possible role of TL1A in the pathogenesis of psoriasis. In this study, serum levels of TL1A in patients with psoriasis vulgaris (PV) and atopic dermatitis (AD) were detected by enzyme-linked immunosorbent assay (ELISA). Then, peripheral blood mononuclear cells (PBMCs) from patients with PV were isolated, the mRNA expression of TL1A was measured by real-time quantitative PCR. The effects of TL1A on the production of T cell cytokines, such as IL-17, IFN-?, IL-4 and IL-10 in PBMCs were determined. We demonstrated that serum TL1A levels were significantly elevated in patients with PV but not in patients with AD. Besides, the high serum TL1A levels in patients with PV decreased after treatment. PBMCs derived from psoriatic patients showed significantly increased TL1A mRNA levels. Soluble TL1A synergized with IL-23 to stimulate PBMCs from patients with PV to produce IL-17. Taken together, these findings strongly suggest that TL1A may play a role in the pathogenesis of PV.
Related JoVE Video
Baseline characteristics and 1-year follow-up of Chinese atrial fibrillation patients according to age: a registry study.
Pacing Clin Electrophysiol
PUBLISHED: 01-09-2014
Show Abstract
Hide Abstract
The prevalence of atrial fibrillation (AF) increases with age, and may lead to complications and reduced quality of life. The aim of this study was to determine the characteristics, management, and prognosis of Chinese AF patients and whether there were differences according to age.
Related JoVE Video
Maternal parity and the risk of congenital heart defects in offspring: a dose-response meta-analysis of epidemiological observational studies.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Epidemiological studies have reported conflicting results regarding maternal parity and the risk of congenital heart defects (CHDs). However, a meta-analysis of the association between maternal parity and CHDs in offspring has not been conducted.
Related JoVE Video
Improving aqueous solubility and antitumor effects by nanosized gambogic acid-mPEG???? micelles.
Int J Nanomedicine
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The clinical application of gambogic acid, a natural component with promising antitumor activity, is limited due to its extremely poor aqueous solubility, short half-life in blood, and severe systemic toxicity. To solve these problems, an amphiphilic polymer-drug conjugate was prepared by attachment of low molecular weight (ie, 2 kDa) methoxy poly(ethylene glycol) methyl ether (mPEG) to gambogic acid (GA-mPEG????) through an ester linkage and characterized by (1)H nuclear magnetic resonance. The GA-mPEG???? conjugates self-assembled to form nanosized micelles, with mean diameters of less than 50 nm, and a very narrow particle size distribution. The properties of the GA-mPEG???? micelles, including morphology, stability, molecular modeling, and drug release profile, were evaluated. MTT (3-(4,5-dimethylthiazo l-2-yl)-2,5 diphenyl tetrazolium bromide) tests demonstrated that the GA-mPEG???? micelle formulation had obvious cytotoxicity to tumor cells and human umbilical vein endothelial cells. Further, GA-mPEG???? micelles were effective in inhibiting tumor growth and prolonged survival in subcutaneous B16-F10 and C26 tumor models. Our findings suggest that GA-mPEG???? micelles may have promising applications in tumor therapy.
Related JoVE Video
[Study of Single Nucleotide Polymorphism of SOCS Gene in Typical Myeloproliferative Neoplasms].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 12-28-2013
Show Abstract
Hide Abstract
This study was purposed to investigate the effect of mutation and single nucleotide polymorphism (SNP) of suppressor of cytokine signaling (SOCS) on the typical myeloproliferative neoplasms(MPN) and its mechanism. The mutation and SNP of SOCS1, SOCS2, SOCS3 genes in 100 MPN patients were detected by RT-PCR and direct sequencing. The results showed that among 100 cases there were 21 cases with A?C polymorphism in the 63th site nucleotide of the 15 SOCS3 exon (SNP library no reported), 18 cases with A?C polymorphism in the 1779th site nucleotide of the 15 SOCS3 exon, 49 cases with A?G polymorphism in the 2249th site nucleotide of the 15 SOCS3 exon (SNP library no reported), 39 cases with T?C polymorphism in the 2366th site nucleotide of the 15 SOCS3 exon (SNP library no reported), 9 cases with T?C polymorphism in the exon of 15 SOCS2 gene (SNP library no reported). SOCS3 SNP was found in patients with significantly advanced age at diagnosis, the leukocyte count and platelet level were higher than those in patients with wild type, JAK2V617 mutations was found in 87.65% SOCS3 SNP. It is concluded that the SOCS may be an important target for anticancer therapy, the single nucleotide polymorphism of SOCS may involve to pathogenesis of MPN.
Related JoVE Video
[Prevention and treatment of complications during and after endoscopic mucosal band ligation for esophageal precancerous lesions and early cancer].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 12-27-2013
Show Abstract
Hide Abstract
To investigate the prevention and treatment of complications during and after endoscopic mucosal band ligation(EMBL) for precancerous lesions and early cancer in the esophagus.
Related JoVE Video
[Genome minimization method based on metabolic network analysis and its application to Escherichia coli].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 12-25-2013
Show Abstract
Hide Abstract
The minimum life is one of the most important research topics in synthetic biology. Minimizing a genome while at the same time maintaining an optimal growth of the cells is one of the important research objectives in metabolic engineering. Here we propose a genome minimization method based on genome scale metabolic network analysis. The metabolic network is minimized by first deleting the zero flux reactions from flux variability analysis, and then by repeatedly calculating the optimal growth rates after combinatorial deletion of the non-essential genes in the reduced network. We applied this method to the classic E. coli metabolic network model ---iAF1260 and successfully reduced the number of genes in the model from 1 260 to 312 while maintaining the optimal growth rate unaffected. We also analyzed the metabolic pathways in the network with the minimized number of genes. The results provide some guidance for the design of wet experiments to obtain an E. coli minimal genome.
Related JoVE Video
[Engineering of the xylose metabolic pathway for microbial production of bio-based chemicals].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 12-25-2013
Show Abstract
Hide Abstract
As the rapid development of economy necessitates a large number of oil, the contradiction between energy supply and demand is further exacerbated by the dwindling reserves of petroleum resource. Therefore, the research of the renewable cellulosic biomass resources is gaining unprecedented momentum. Because xylose is the second most abundant monosaccharide after glucose in lignocellulose hydrolyzes, high-efficiency bioconversion of xylose becomes one of the vital factors that affect the industrial prospects of lignocellulose application. According to the research progresses in recent years, this review summarized the advances in bioconversion of xylose, which included identification and redesign of the xylose metabolic pathway, engineering the xylose transport pathway and bio-based chemicals production. In order to solve the energy crisis and environmental pollution issues, the development of advanced bio-fuel technology, especially engineering the microbe able to metabolize xylose and produce ethanol by synthetic biology, is environmentally benign and sustainable.
Related JoVE Video
[Combinatorial optimization of synthetic biological systems].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 12-25-2013
Show Abstract
Hide Abstract
A major challenge in synthetic biology is to engineer complex biological systems with novel functions. Due to the inherent complexity of biological systems, it is often difficult to rationally design every component in a synthetic gene network to achive an optimal performance. Combinatorial engineering is an important solution to this problem and can greatly facilitate the construction of novel biological functions. Here, we review methods and techniques developed in recent years for combinatorial optimization of synthetic biological systems, including methods for fine-tuning pathway components, strategies for systematically optimization of metabolic pathways, and techniques for introducing multiplex genome wide perturbations.
Related JoVE Video
NH4HF2 as a Selective TBS-Removal Reagent for the Synthesis of Highly Functionalized Spiroketal via Tandem Deprotection/Spiroketalization Procedure.
J. Org. Chem.
PUBLISHED: 12-24-2013
Show Abstract
Hide Abstract
NH4HF2 has been used for the first time to selectively remove the TBS protecting groups from diol ketone precursors in the synthesis of highly functionalized spiroketals. This method allows the synthesis of [5,6], [6,6], and [6,7] spiroketal skeletons, as well as benzannulated spiroketal with retention of acid-sensitive groups. In this way, spiroketals can be synthesized with diverse substituent groups in the skeleton or on side chains. To demonstrate the utility of this methodology, the diverse transformations of highly functionalized spiroketal 3f were also investigated.
Related JoVE Video
Transparent and Stretchable High-Performance Supercapacitors Based on Wrinkled Graphene Electrodes.
ACS Nano
PUBLISHED: 12-23-2013
Show Abstract
Hide Abstract
Transparent and/or stretchable energy storage devices have attracted intense attention due to their unique optical and/or mechanical properties as well as their intrinsic energy storage function. However, it remains a great challenge to integrate transparent and stretchable properties into an energy storage device because the currently developed electrodes are either transparent or stretchable, but not both. Herein, we report a simple method to fabricate wrinkled graphene with high stretchability and transparency. The resultant wrinkled graphene sheets were used as both current collector and electrode materials to develop transparent and stretchable supercapacitors, which showed a high transparency (57% at 550 nm) and can be stretched up to 40% strain without obvious performance change over hundreds of stretching cycles.
Related JoVE Video
Systematic Analyses of the Transcriptome, Translatome, and Proteome Provide a Global View and Potential Strategy for the C-HPP.
J. Proteome Res.
PUBLISHED: 12-16-2013
Show Abstract
Hide Abstract
To estimate the potential of the state-of-the-art proteomics technologies on full coverage of the encoding gene products, the Chinese Human Chromosome Proteome Consortium (CCPC) applied a multiomics strategy to systematically analyze the transciptome, translatome, and proteome of the same cultured hepatoma cells with varied metastatic potential qualitatively and quantitatively. The results provide a global view of gene expression profiles. The 9064 identified high confident proteins covered 50.2% of all gene products in the translatome. Those proteins with function of adhesion, development, reproduction, and so on are low abundant in transcriptome and translatome but absent in proteome. Taking the translatome as the background of protein expression, we found that the protein abundance plays a decisive role and hydrophobicity has a greater influence than molecular weight and isoelectric point on protein detectability. Thus, the enrichment strategy used for low-abundant transcription factors helped to identify missing proteins. In addition, those peptides with single amino acid polymorphisms played a significant role for the disease research, although they might negligibly contribute to new protein identification. The proteome raw and metadata of proteome were collected using the iProX submission system and submitted to ProteomeXchange (PXD000529, PXD000533, and PXD000535). All detailed information in this study can be accessed from the Chinese Chromosome-Centric Human Proteome Database.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

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.