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Find video protocols related to scientific articles indexed in Pubmed.
[Analysis of lymphoma incidence in Beijing, 1998-2010].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 11-13-2014
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To analyze the incidence trends and characteristics of lymphoma in Beijing, 1998-2010.
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[Analysis of incidence and mortality of thyroid cancer in China, 2010].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 11-13-2014
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To analysis the incidence and mortality status of thyroid cancer in China, 2010.
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Organic functionalisation of graphene catalysed by ferric perchlorate.
Chem. Commun. (Camb.)
PUBLISHED: 11-04-2014
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We have developed a method to prepare covalently functionalised graphene using ferric perchlorate as the catalyst. The resulting functionalised graphene was characterised by Raman spectroscopy, TGA, XPS, AFM, and dispersibility tests in organic or aqueous media.
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Study of beam transverse properties of a thermionic electron gun for application to a compact THz free electron laser.
Rev Sci Instrum
PUBLISHED: 11-03-2014
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A novel thermionic electron gun adopted for use in a high power THz free electron laser (FEL) is proposed in this paper. By optimization of the structural and radiofrequency (RF) parameters, the physical design of the gun is performed using dynamic calculations. Velocity bunching is used to minimize the bunch's energy spread, and the dynamic calculation results indicate that high quality beams can be provided. The transverse properties of the beams generated by the gun are also analyzed. The novel RF focusing effects of the resonance cavity are investigated precisely and are used to establish emittance compensation, which enables the injector length to be reduced. In addition, the causes of the extrema of the beam radius and the normalized transverse emittance are analyzed and interpreted, respectively, and slice simulations are performed to illustrate how the RF focusing varies along the bunch length and to determine the effects of that variation on the emittance compensation. Finally, by observation of the variations of the beam properties in the drift tube behind the electron gun, prospective assembly scenarios for the complete THz-FEL injector are discussed, and a joint-debugging process for the injector is implemented.
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MoS2 nanosheet/TiO2 nanowire hybrid nanostructures for enhanced visible-light photocatalytic activities.
Chem. Commun. (Camb.)
PUBLISHED: 10-29-2014
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We report one dimensional (1D) MoS2 nanosheet/porous TiO2 nanowire hybrid nanostructures synthesized by a simple hydrothermal method, leading to an enhanced specific surface area (66 m(2) g(-1)). These 1D hybrid nanostructures as co-catalysts exhibit high activity in visible light photocatalytic hydrogen evolution reaction (HER) with an enhanced hydrogen generation rate of 16.7 mmol h(-1) g(-1).
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Ganoderma lucidum polysaccharide exerts anti-tumor activity via MAPK pathways in HL-60 acute leukemia cells.
J. Recept. Signal Transduct. Res.
PUBLISHED: 10-21-2014
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Abstract In this study, we investigated the anti-tumor activity both in vitro and in vivo of a polysaccharide obtained from Ganoderma lucidum on HL-60 acute myeloid leukemia cells, and focused on its targeting effect on mitogen-activated protein kinase (MAPK) pathways. It was found by the methods such as western blot and flow cytometry (FCM), that G. lucidum polysaccharide (GLP) blocked the extracellular signal-regulated kinase/MAPK signaling pathway, simultaneously activated p38 and JNK MAPK pathways, and therefore regulated their downstream genes and proteins, including p53, c-myc, c-fos, c-jun, Bcl-2, Bax, cleaved caspase-3 and cyclin D1. As a result, cycle arrest and apoptosis of HL-60 cells were induced. Therefore, GLP exerted anti-tumor activity via MAPK pathways in HL-60 acute leukemia cells.
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Intravenous Anesthetic Propofol Inhibits Multiple Human Cardiac Potassium Channels.
Anesthesiology
PUBLISHED: 10-17-2014
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Propofol is widely used clinically for the induction and maintenance of anesthesia. Clinical case reports have shown that propofol has an antiatrial tachycardia/fibrillation effect; however, the related ionic mechanisms are not fully understood. The current study investigates the effects of propofol on human cardiac potassium channels.
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A reverberation chamber for rodents' exposure to wideband radiofrequency electromagnetic fields with different small-scale fading distributions.
Electromagn Biol Med
PUBLISHED: 09-27-2014
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Abstract A reverberation chamber (RC) is realized for the rodents' in vivo exposure to electromagnetic fields (EMFs) with various small-scale fading characteristics. Its performance is evaluated to ensure the exposure experiments from 0.85 to 2.60?GHz. By different configurations, line-of-sight and non-line-of-sight exposures can be established. The measured electric field in the RC is analyzed to determine its statistical distribution. We accordingly reconstruct the EMF environment by numerical methods. Simulations are carried to compare the dosimetric variability due to different small-scale fading characteristics. It demonstrates that the surveyed fading distribution will not change the specific absorption rate in the rats. The possibility to reproduce the realistic multi-reflective EMF environment by adjusting the structures of the RC is discussed. It is the first reported in vivo exposure system aiming to provide the EMF exposure with different small-scale fading distributions.
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[Fc?RIII a polymorphisms and efficacy of Rituximab combined chemotherapy for diffuse large B-cell lymphoma in Chinese patients].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 09-24-2014
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To evaluate the impact of Fc gamma receptor IIIa (Fc?R IIIa) polymorphisms on the efficacy of rituximab (RTX) combined chemotherapy for patients with diffuse large B-cell lymphoma (DLBCL).
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Study familial hypertrophic cardiomyopathy using patient-specific induced pluripotent stem cells.
Cardiovasc. Res.
PUBLISHED: 09-10-2014
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Familial hypertrophic cardiomyopathy (HCM) is one the most common heart disorders, with gene mutations in the cardiac sarcomere. Studying HCM with patient-specific induced pluripotent stem-cell (iPSC)-derived cardiomyocytes (CMs) would benefit the understanding of HCM mechanism, as well as the development of personalized therapeutic strategies.
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Crystal structure of di-?-hydroxido-bis{[N,N'-bis-(2,6-di-methyl-phen-yl)pentane-2,4-diiminato(1-)]zinc}.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 09-01-2014
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The title compound, [Zn2(C21H25N2)2(OH)2], is a binuclear zinc complex formed by two bidentate ?-diketiminate (nacnac) ligands and two ?-hydroxide O atoms, bridging two mononuclear units into a centrosymmetric dimeric unit. Each Zn(2+) cation is coordinated by two N-donor atoms from the nacnac ligand and two O-donor atoms of hydroxide anions to give a distorted tetra-hedral coordination environment. The Zn-O bond lengths are 1.9643?(13) and 2.0022?(14)?Å, and the two Zn-N bond lengths are 1.9696?(14) and 1.9823?(14)?Å. The distance between the two Zn(2+) cations in the dimer is 2.9420?(4)?Å. Although hydroxide groups are present in the complex, no classical hydrogen-bonding inter-ations are observed because of the bulky ?-diketiminate ligands.
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Positive selection and multiple losses of the LINE-1-derived L1TD1 gene in mammals suggest a dual role in genome defense and pluripotency.
PLoS Genet.
PUBLISHED: 09-01-2014
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Mammalian genomes comprise many active and fossilized retroelements. The obligate requirement for retroelement integration affords host genomes an opportunity to 'domesticate' retroelement genes for their own purpose, leading to important innovations in genome defense and placentation. While many such exaptations involve retroviruses, the L1TD1 gene is the only known domesticated gene whose protein-coding sequence is almost entirely derived from a LINE-1 (L1) retroelement. Human L1TD1 has been shown to play an important role in pluripotency maintenance. To investigate how this role was acquired, we traced the origin and evolution of L1TD1. We find that L1TD1 originated in the common ancestor of eutherian mammals, but was lost or pseudogenized multiple times during mammalian evolution. We also find that L1TD1 has evolved under positive selection during primate and mouse evolution, and that one prosimian L1TD1 has 'replenished' itself with a more recent L1 ORF1 from the prosimian genome. These data suggest that L1TD1 has been recurrently selected for functional novelty, perhaps for a role in genome defense. L1TD1 loss is associated with L1 extinction in several megabat lineages, but not in sigmodontine rodents. We hypothesize that L1TD1 could have originally evolved for genome defense against L1 elements. Later, L1TD1 may have become incorporated into pluripotency maintenance in some lineages. Our study highlights the role of retroelement gene domestication in fundamental aspects of mammalian biology, and that such domesticated genes can adopt different functions in different lineages.
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Synergistic transcriptional and post-transcriptional regulation of ESC characteristics by core pluripotency transcription factors in protein-protein interaction networks.
PLoS ONE
PUBLISHED: 08-29-2014
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The molecular mechanism that maintains the pluripotency of embryonic stem cells (ESCs) is not well understood but may be reflected in complex biological networks. However, there have been few studies on the effects of transcriptional and post-transcriptional regulation during the development of ESCs from the perspective of computational systems biology. In this study, we analyzed the topological properties of the "core" pluripotency transcription factors (TFs) OCT4, SOX2 and NANOG in protein-protein interaction networks (PPINs). Further, we identified synergistic interactions between these TFs and microRNAs (miRNAs) in PPINs during ESC development. Results show that there were significant differences in centrality characters between TF-targets and non-TF-targets in PPINs. We also found that there was consistent regulation of multiple "core" pluripotency TFs. Based on the analysis of shortest path length, we found that the module properties were not only within the targets regulated by common or multiple "core" pluripotency TFs but also between the groups of targets regulated by different TFs. Finally, we identified synergistic regulation of these TFs and miRNAs. In summary, the synergistic effects of "core" pluripotency TFs and miRNAs were analyzed using computational methods in both human and mouse PPINs.
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Palladium-catalyzed asymmetric decarboxylative cycloaddition of vinylethylene carbonates with Michael acceptors: construction of vicinal quaternary stereocenters.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-28-2014
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An efficient method for the diastereo- and enantioselective construction of vicinal all-carbon quaternary stereocenters through palladium-catalyzed decarboxylative cycloaddition of vinylethylene carbonates with activated Michael acceptors was developed. By using a palladium complex generated in?situ from [Pd2 (dab)3 ]?CHCl3 and a phosphoramidite ligand as a catalyst under mild reaction conditions, the process provides multifunctionalized tetrahydrofurans bearing vicinal all-carbon quaternary stereocenters in high yields with a high level of absolute and relative stereocontrol.
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Analysis and identification of essential genes in humans using topological properties and biological information.
Gene
PUBLISHED: 08-27-2014
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Genes that are indispensable for survival are termed essential genes. The analysis and identification of essential genes are very important for understanding the minimal requirements of cellular survival and for practical purposes. Proteins do not exert their function in isolation of one another but rather interact together in PPI networks. A global analysis of protein interaction networks provides an effective way to elucidate the relationships between proteins. With the recent large-scale identifications of essential genes and the production of large amounts of PPIs in humans, we are able to investigate the topological properties and biological properties of essential genes. However, until recently, no one has ever investigated human essential genes using topological and biological properties. In this study, for the first time, 28 topological properties and 22 biological properties were used to investigate the characteristics of essential and non-essential genes in humans. Most of the properties were statistically discriminative between essential and non-essential genes. The F-score was used to estimate the essentiality of each property. The GO-enrichment analysis was performed to investigate the functions of the essential and non-essential genes. Finally, based on the topological features and the biological characteristics, a machine-learning classifier was constructed to predict the essential genes. The results of the jackknife test and 10-fold cross validation test are encouraging, indicating that our classifier is an effective human essential gene discovery method.
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Very small embryonic-like cells in the mirror of regenerative medicine.
J Stem Cells
PUBLISHED: 08-27-2014
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Regenerative medicine with the promise of complete organ restoration could change the treatment paradigm for various degenerative disorders. In order to develop successful, safe and efficient regenerative therapies, appropriate amount of pluripotent autologous cells are desired. Pluripotent stem cell lines, such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), offer a unique opportunity to derive various cell types that can be exploited for regenerative medicine. However, their application in therapies is limited due to inherent potential tumorigenesis, problems with immune-rejection, applied reprogramming methods, and ethical considerations. Recent reports on the establishment of very small embryonic-like cells (VSELs) are pointing to a way out of this dilemma, since it is proposed that these cells have similar characteristics as ESCs and could serve as basis for therapeutic applications. A careful scientific comparison of VSELs is now needed in order to make judgments about their capabilities and characteristics. In any case, the development of successful, safe and efficient regenerative therapies based on human pluripotent cells requires additional quality assessments of critical parameters that are also summarized within the review.
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[Influencing factors of disease progression for asymptomatic osteonecrosis of the femoral head].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-26-2014
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To analyze the progression of asymptomatic osteonecrosis of the femoral head by evaluating its lesion size and location.
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The characteristics of a novel heterotrophic nitrifying and aerobic denitrifying bacterium, Acinetobacter junii YB.
Bioresour. Technol.
PUBLISHED: 08-19-2014
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A novel heterotrophic nitrifying bacterium was isolated from activated sludge and was identified as Acinetobacter junii YB. The strain exhibited efficient heterotrophic nitrification-aerobic denitrification ability at a broad range of ammonium loads and had the capability to utilize hydroxylamine, nitrite and nitrate as a sole nitrogen source. Based on the nitrogen removal and enzyme assay, the nitrogen removal pathway was speculated to be achieved through heterotrophic nitrification coupled with aerobic denitrification. In addition, single-factor experiments showed that efficient heterotrophic nitrification and growth of strain YB occurred with succinate as the carbon source, pH 7.5, 37 °C, and high C/N ratio and dissolved oxygen. Furthermore, the new isolate showed capacities for aggregation and hydrophobicity. Regular variations of the flocculating ability and relative hydrophobicity were observed during the whole cultivation. The ability to perform heterotrophic nitrification-aerobic denitrification and cell aggregation demonstrated the great potential of the strain YB for future applications.
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Development of BODIPY FL vindoline as a novel and high-affinity pregnane X receptor fluorescent probe.
Bioconjug. Chem.
PUBLISHED: 08-18-2014
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The pregnane X receptor (PXR) regulates the metabolism and excretion of xenobiotics and endobiotics by regulating the expression of drug-metabolizing enzymes and transporters. The unique structure of PXR allows it to bind many drugs and drug leads, possibly causing undesired drug-drug interactions. Therefore, it is crucial to evaluate whether chemicals or drugs bind to PXR. Fluorescence-based assays are preferred because of their sensitivity and nonradioactive nature. On the basis of our previously characterized 4 (BODIPY FL vinblastine), a high-affinity PXR probe, we developed 20 (BODIPY FL vindoline) and showed that it is a novel and potent PXR fluorescent probe with Kd of 256 nM in a time-resolved fluorescence resonance energy transfer (TR-FRET) binding assay with PXR. By using 20 (BODIPY FL vindoline) in the PXR TR-FRET assay, we obtained a more than 7-fold signal-to-background ratio and high signal stability (signal was stable for at least 120 min, and Z'-factor > 0.85 from 30 to 240 min). The assay can tolerate DMSO up to 2%. This assay has been used to evaluate a panel of PXR ligands for their PXR-binding affinities. The performance of 20 (BODIPY FL vindoline) in the PXR TR-FRET assay makes it an ideal PXR fluorescent probe, and the newly developed PXR TR-FRET assay with 20 (BODIPY FL vindoline) as a fluorescent probe is suitable for high-throughput screening to identify PXR-binding ligands.
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Possible antioxidant mechanism of melanoidins extract from Shanxi aged vinegar in mitophagy-dependent and mitophagy-independent pathways.
J. Agric. Food Chem.
PUBLISHED: 08-14-2014
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Melanoidins are widely reported to have antioxidant activity; however, their mechanism has not been frequently studied. In this study, we found that melanoidins from Shanxi aged vinegar induced mitopahgy, the specific autophagic elimination of mitochondria, as assessed by up-regulation of the autophagy markers LC3-II and Beclin1 as well as degradation of the autophagy substrate p62 and mitochondrial proteins. Melanoidins reduced reactive oxygen species (ROS) in normal human liver cells and mouse livers through a mitophagy-dependent pathway, by the observation that the reducing ROS effect of melanoidins was partially lost when mitophagy was inhibited by chloroquine. Impaired Akt signaling was found in cells treated with melanoidins, which might explain the activation of autophagy induced by melanoidins. These results suggest that in addition to direct free radical scavenging activity, melanoidins decreased ROS levels through mitophagy in which damaged mitochondria, the source of ROS, were degraded.
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Potential effects of large linear pipeline construction on soil and vegetation in ecologically fragile regions.
Environ Monit Assess
PUBLISHED: 08-12-2014
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Long-distance pipeline construction results in marked human disturbance of the regional ecosystem and brings into question the safety of pipeline construction with respect to the environment. Thus, the direct environmental impact and proper handling of such large projects have received much attention. The potential environmental effects, however, have not been fully addressed, particularly for large linear pipeline projects, and the threshold of such effects is unclear. In this study, two typical eco-fragile areas in western China, where large linear construction projects have been conducted, were chosen as the case study areas. Soil quality indices (SQI) and vegetation indices (VI), representing the most important potential effects, were used to analyze the scope of the effect of large pipeline construction on the surrounding environment. These two indices in different buffer zones along the pipeline were compared against the background values. The analysis resulted in three main findings. First, pipeline construction continues to influence the nearby eco-environment even after a 4-year recovery period. During this period, the effect on vegetation due to pipeline construction reaches 300 m beyond the working area, and is much larger in distance than the effect on soil, which is mainly confined to within 30 m either side of the pipeline, indicating that vegetation is more sensitive than soil to this type of human disturbance. However, the effect may not reach beyond 500 m from the pipeline. Second, the scope of the effect in terms of distance on vegetation may also be determined by the frequency of disturbance and the intensity of the pipeline construction. The greater the number of pipelines in an area, the higher the construction intensity and the more frequent the disturbance. Frequent disturbance may expand the effect on vegetation on both sides of the pipeline, but not on soil quality. Third, the construction may eliminate the stable, resident plant community. During the recovery period, the plant community in the work area of the pipeline is replaced by some species that are rare or uncommon in the resident plant community because of human disturbance, thereby increasing the plant diversity in the work area. In terms of plant succession, the duration of the recovery period has a direct effect on the composition and structure of the plant community. The findings provide a theoretical basis and scientific foundation for improving the environmental impact assessment (EIA) of oil and gas pipeline construction as it pertains to the desert steppe ecosystem, and provide a reference point for recovery and management of the eco-environment during the pipeline construction period.
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Ion conduction and selectivity in acid-sensing ion channel 1.
J. Gen. Physiol.
PUBLISHED: 08-11-2014
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The ability of acid-sensing ion channels (ASICs) to discriminate among cations was assessed based on changes in conductance and reversal potential with ion substitution. Human ASIC1a was expressed in Xenopus laevis oocytes, and acid-induced currents were measured using two-electrode voltage clamp. Replacement of extracellular Na(+) with Li(+), K(+), Rb(+), or Cs(+) altered inward conductance and shifted the reversal potentials consistent with a selectivity sequence of Li ? Na > K > Rb > Cs. Permeability decreased more rapidly than conductance as a function of atomic size, with P(K)/P(Na) = 0.1 and G(K)/G(Na) = 0.7 and P(Rb)/P(Na) = 0.03 and G(Rb)/G(Na) = 0.3. Stimulation of Cl(-) currents when Na(+) was replaced with Ca(2+), Sr(2+), or Ba(2+) indicated a finite permeability to divalent cations. Inward conductance increased with extracellular Na(+) in a hyperbolic manner, consistent with an apparent affinity (K(m)) for Na(+) conduction of 25 mM. Nitrogen-containing cations, including NH4(+), NH3OH(+), and guanidinium, were also permeant. In addition to passing through the channels, guanidinium blocked Na(+) currents, implying competition for a site within the pore. The role of negative charges in an external vestibule of the pore was evaluated using the point mutation D434N. The mutant channel had a decreased single-channel conductance, measured in excised outside-out patches, and a macroscopic slope conductance that increased with hyperpolarization. It had a weakened interaction with Na(+) (K(m) = 72 mM) and a selectivity that was shifted toward larger atomic sizes. We conclude that the selectivity of ASIC1 is based at least in part on interactions with binding sites both within and internal to the outer vestibule.
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Blockade of epidermal growth factor receptor/mammalian target of rapamycin pathway by Icariside II results in reduced cell proliferation of osteosarcoma cells.
Food Chem. Toxicol.
PUBLISHED: 08-10-2014
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Icariside II is considered one of the most important natural flavonoids with multiple bioactivities from traditional Chinese medicine Yin Yanghuo (YYH) or Horny Goat Weed (Epimedium koreanum Nakai). Previous studies show that Icariside II exhibits potent cytotoxicity against a broad spectrum of human cancer cells through various signaling transduction pathways. However, there are few reports about the effect of Icariside II on osteosarcoma cell. In this study, we found that Icariside II decreased cell proliferation in human osteosarcoma MG-63 cells and human osteosarcoma Saos-2 cells. In addition, Icariside II inactivated EGFR/mTOR signaling pathway, including EGFR, PI3K/AKT/PRAS40, Raf/MEK/ERK as well as mTOR. Furthermore, Icariside II inhibited epidermal growth factor (EGF)-induced activation of EGFR/mTOR signaling pathway. Pretreatment of EGF partially reversed cell viability decreased by Icariside II. Importantly, Icariside II inhibited the proliferation of transplantable tumors and EGFR/mTOR signaling pathway in sarcoma-180 bearing mice. In summary, these results indicate that Icariside II inhibits the proliferation of osteosarcoma cells in vitro and in vivo via EGFR/mTOR signaling pathway.
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A description of the mitogenome of the Endangered Taiwanese angelshark, Squatina formosa.
Mitochondrial DNA
PUBLISHED: 08-05-2014
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Abstract Squatinid sharks are among the most threatened of cartilaginous fishes. Here we describe the complete mitochondrial genome sequence (16,690?bp) of the Endangered Taiwanese angelshark, Squatina formosa. It has 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 control region in the typical vertebrate arrangement.
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Re-characterization of Some Factors Influencing Aerosol Sampling in the Workplace: Results from Field Studies.
J Occup Health
PUBLISHED: 07-25-2014
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Objective: Workplace aerosol sampling is challenged by its influencing factors and methodological limitations. Some factors, including blank setting, electrostatic effect, sample mass gain, and limit of detection (LOD), were studied to characterize them further and thereby to improve the sampling method. Methods: Through a field sampling in two shipyards and by an analysis of a large amount of dust data from different industries, the influencing factors were comparatively studied with emphasis on their effect on the final result. Results: After calibration with field blanks, the concentrations of most sample types in the shipyards decreased significantly, varying by as much as -24.3% of the final measurements. After laboratory blank calibration, dust concentrations increased or decreased without a definite change trend. With a variation of -1.8%, only the measurements of Chinese "total dust" sampled with polypropylene filters were significantly influenced by the electrostatic effect. The LOD coincidence rate was only 17.3% for American respirable dust in different industries and 12.2% for respirable particles collected by normal flow rate samplers (FSP2) in the shipyards. The latter increased to 73.9% when high flow samplers (FSP10) were used. Conclusion: It was suggested that field blank calibration was the predominant influencing factor in comparison with electrostatic effect and laboratory blank adjustment. The LOD coincidence rate was too low for reliable sampling, and this might be improved by use of high flow samplers.
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[Advance in studies on anti-diabetic mechanism of Gardeniae Fructus and its active ingredient geniposide].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 07-22-2014
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The diabetes is mainly treated by the oral administration of western medicines at present. Despite their rapid curative effect, there have been still many reports for the western medicines about their clinical adverse reactions, failure of effective prevention and treatment of complications and drug resistance. Hence, they are not suitable for long-term administration. Traditional Chinese medicines have a long history in treating diabetes mellitus (DM) , which is commonly known as Xiaokezheng in the theory of traditional Chinese medicines. In recent years, many scholars have taken extracts from traditional Chinese medicines or separated active constituents as the study objects in the expectation of developing new-type drugs for treating and preventing diabetes. Therefore, a large number of study reports have been emerged in this field. Due to their significant glucose-reducing effect and specific effect in treating complications of diabetes, traditional Chinese medicine Gardeniae Fructus and its iridoid component geniposide shall be given full attention. This paper summarized the advance in studies on the curative effect and action mechanism of Gardeniae Fructus and geniposide in preventing and treating diabetes.
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Generation of infant anatomical models for evaluating electromagnetic field exposures.
Bioelectromagnetics
PUBLISHED: 07-06-2014
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Realistic anatomical modeling is essential in analyzing human exposure to electromagnetic fields. Infants have significant physical and anatomical differences compared with other age groups. However, few realistic infant models are available. In this work, we developed one 12-month-old male whole body model and one 17-month-old male head model from magnetic resonance images. The whole body and head models contained 28 and 30 tissues, respectively, at spatial resolution of 1?mm?×?1?mm?×?1?mm. Fewer identified tissues in the whole body model were a result of the low original image quality induced by the fast imaging sequence. The anatomical and physical parameters of the models were validated against findings in published literature (e.g., a maximum deviation as 18% in tissue mass was observed compared with the data from International Commission on Radiological Protection). Several typical exposure scenarios were realized for numerical simulation. Dosimetric comparison with various adult and child anatomical models was conducted. Significant differences in the physical and anatomical features between adult and child models demonstrated the importance of creating realistic infant models. Current safety guidelines for infant exposure to radiofrequency electromagnetic fields may not be conservative. Bioelectromagnetics 9999:1-17, 2014. © 2014 Wiley Periodicals, Inc.
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Optimization of ionic liquid based simultaneous ultrasonic- and microwave-assisted extraction of rutin and quercetin from leaves of velvetleaf (Abutilon theophrasti) by response surface methodology.
ScientificWorldJournal
PUBLISHED: 07-03-2014
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An ionic liquids based simultaneous ultrasonic and microwave assisted extraction (ILs-UMAE) method has been proposed for the extraction of rutin (RU), quercetin (QU), from velvetleaf leaves. The influential parameters of the ILs-UMAE were optimized by the single factor and the central composite design (CCD) experiments. A 2.00 M 1-butyl-3-methylimidazolium bromide ([C4mim]Br) was used as the experimental ionic liquid, extraction temperature 60°C, extraction time 12 min, liquid-solid ratio 32 mL/g, microwave power of 534 W, and a fixed ultrasonic power of 50 W. Compared to conventional heating reflux extraction (HRE), the RU and QU extraction yields obtained by ILs-UMAE were, respectively, 5.49 mg/g and 0.27 mg/g, which increased, respectively, 2.01-fold and 2.34-fold with the recoveries that were in the range of 97.62-102.36% for RU and 97.33-102.21% for QU with RSDs lower than 3.2% under the optimized UMAE conditions. In addition, the shorter extraction time was used in ILs-UMAE, compared with HRE. Therefore, ILs-UMAE was a rapid and an efficient method for the extraction of RU and QU from the leaves of velvetleaf.
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Maternal lifestyle factors in pregnancy and congenital heart defects in offspring: review of the current evidence.
Ital J Pediatr
PUBLISHED: 06-22-2014
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The prognosis of children with congenital heart defects(CHDs) continues to improve with advancing surgical techniques; however, lack of information about modifiable risk factors for malformations in cardiovascular development impeded the prevention of CHDs. We investigated an association between maternal lifestyle factors and the risk of CHDs, because epidemiological studies have reported conflicting results regarding maternal lifestyle factors and the risk of CHDs recently. A review published on 2007 provided a summary of maternal exposures associated with an increased risk of CHDs. As part of noninherited risk factors, we conducted a brief overview of studies on the evidence linking common maternal lifestyle factors, specifically smoking, alcohol, illicit drugs, caffeine, body mass index and psychological factors to the development of CHDs in offspring. Women who smoke and have an excessive body mass index(BMI) during pregnancy are suspected to be associated with CHDs in offspring. Our findings could cause public health policy makers to pay more attention to women at risk and could be used in the development of population-based prevention strategies to reduce the incidence and burden of CHDs. However, more prospective studies are needed to investigate the association between maternal lifestyle factors and CHDs.
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Network approach to the pinning control of drift-wave turbulence.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 06-18-2014
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Network of coupled oscillators has long been employed as an important approach to explore the complicated dynamics in spatially extended systems. Here we show how this approach can be used to the analysis of turbulence pinning control. Specifically, by use of a model of two-dimensional drift-wave plasma turbulence, we investigate how the performance of the turbulence control is influenced by the spatial distribution of the pinning strength. It is found that the dynamics of pinned turbulence can be well captured by a simple model of networked modes, based on which the dependence of the control performance on the pinning distribution can be analytically obtained. In particular, the model predicts that as the distribution of the pinning strength becomes more nonuniform, the performance of turbulence control will be gradually decreased. This theoretical prediction is in good agreement with the results of numerical simulations, including the sinusoidal and localized pinning distributions. Our studies provide a new viewpoint to the mechanism of mode couplings in drift-wave turbulence, as well as be constructive to the design of new schemes for controlling turbulence in realistic systems.
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Suppression of autophagy augments the radiosensitizing effects of STAT3 inhibition on human glioma cells.
Exp. Cell Res.
PUBLISHED: 06-16-2014
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Radiotherapy is an essential component of the standard therapy for newly diagnosed glioblastoma. To increase the radiosensitivity of glioma cells is a feasible solution to improve the therapeutic effects. It has been suggested that inhibition of signal transducer and activator of transcription 3 (STAT3) can radiosensitize glioma cells, probably via the activation of mitochondrial apoptotic pathway. In this study, human malignant glioma cells, U251 and A172, were treated with an STAT3 inhibitor, WP1066, or a short hairpin RNA plasmid targeting STAT3 to suppress the activation of STAT3 signaling. The radiosensitizing effects of STAT3 inhibition were confirmed in glioma cells. Intriguingly, combination of ionizing radiation exposure and STAT3 inhibition triggered a pronounced increase of autophagy flux. To explore the role of autophagy, glioma cells were treated with 3-methyladenine or siRNA for autophagy-related gene 5, and it was demonstrated that inhibition of autophagy further strengthened the radiosensitizing effects of STAT3 inhibition. Accordingly, more apoptotic cells were induced by the dual inhibition of autophagy and STAT3 signaling. In conclusion, our data revealed a protective role of autophagy in the radiosensitizing effects of STAT3 inhibition, and inhibition of both autophagy and STAT3 might be a potential therapeutic strategy to increase the radiosensitivity of glioma cells.
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Permanent genetic memory with >1-byte capacity.
Nat. Methods
PUBLISHED: 06-02-2014
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Genetic memory enables the recording of information in the DNA of living cells. Memory can record a transient environmental signal or cell state that is then recalled at a later time. Permanent memory is implemented using irreversible recombinases that invert the orientation of a unit of DNA, corresponding to the [0,1] state of a bit. To expand the memory capacity, we have applied bioinformatics to identify 34 phage integrases (and their cognate attB and attP recognition sites), from which we build 11 memory switches that are perfectly orthogonal to each other and the FimE and HbiF bacterial invertases. Using these switches, a memory array is constructed in Escherichia coli that can record 1.375 bytes of information. It is demonstrated that the recombinases can be layered and used to permanently record the transient state of a transcriptional logic gate.
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A functional polymorphism in the 3'-UTR of PXR interacts with smoking to increase lung cancer risk in southern and eastern Chinese smoker.
Int J Mol Sci
PUBLISHED: 05-20-2014
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Pregnane X receptor (PXR) is an important member of the nuclear receptor superfamily that copes with various endobiotic and xenobiotic stimuli, such as carcinogens by regulating an array of environmental response genes. Low PXR expression has been shown to promote tumor initiation and metastasis. The aim of the current study was to investigate whether the single nucleotide polymorphisms (SNPs) of PXR could alter lung cancer susceptibility in Chinese by affecting the function or expression of PXR. We genotyped three putatively functional SNPs of PXR (i.e., rs3814055C>T, rs3732360C>T, and rs3814058C>T) and analyzed their associations with lung cancer risk in a two-stage case-control study with a total of 1559 lung cancer cases and 1679 controls in the southern and eastern Chinese population. We found that in comparison to the rs3814058CC common genotype, the rs3814058T variants (TC/TT) which is located in the 3'-untranslated region (3'-UTR) of PXR conferred a consistently increased risk of lung cancer in both the southern Chinese (odd ratios (OR)=1.24, 95% confidence interval (CI)=1.03-1.49) and the eastern Chinese (OR=1.33, 95% CI=1.02-1.75). The variants also significantly interacted with smoking on increasing cancer risk (p=0.023). Moreover, lung cancer tissues with the rs3814058T variants showed significantly lower PXR expression than those with rs3814058CC genotype in the smokers (p=0.041). These results suggested that the rs3814058C>T polymorphism of PXR interacts with smoking on increasing lung cancer risk in Chinese smokers, which might be a functional genetic biomarker for lung cancer.
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Combined biophysical and soluble factor modulation induces cardiomyocyte differentiation from human muscle derived stem cells.
Sci Rep
PUBLISHED: 05-19-2014
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Cellular cardiomyoplasty has emerged as a novel therapy to restore contractile function of injured failing myocardium. Human multipotent muscle derived stem cells (MDSC) can be a potential abundant, autologous cell source for cardiac repair. However, robust conditions for cardiomyocyte (CM) differentiation are not well established for this cell type. We have developed a new method for CM differentiation from human MDSC that combines 3-dimensional artificial muscle tissue (AMT) culture with temporally controlled biophysical cell aggregation and delivery of 4 soluble factors (microRNA-206 inhibitor, IWR-1, Lithium Chloride, and BMP-4) (4F-AG-AMT). The 4F-AG-AMT displayed cardiac-like response to ?-adrenergic stimulation and contractile properties. 4F-AG-AMT expressed major cardiac (NKX2-5, GATA4, TBX5, MEF2C) transcription factors and structural proteins. They also express cardiac gap-junction protein, connexin-43, similar to CMs and synchronized spontaneous calcium transients. These results highlight the importance of temporal control of biophysical and soluble factors for CM differentiation from MDSCs.
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The galloyl catechins contributing to main antioxidant capacity of tea made from Camellia sinensis in China.
ScientificWorldJournal
PUBLISHED: 05-17-2014
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Total polyphenol content, catechins content, and antioxidant capacities of green, dark, oolong, and black teas made from Camellia sinensis in China were evaluated. The total polyphenol content of 20 samples of tea was in the range of 7.82-32.36%. Total catechins content was in the range of 4.34-24.27%. The antioxidant capacity of tea extract was determined by the oxygen radical absorbance capacity (ORAC) test and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging test. Total polyphenol content, catechins content, and antioxidant capacity decreased in the following order: green > oolong > black > dark tea. A positive correlation existed between the antioxidant capacity and total polyphenol content or catechins content (R (2) = 0.67-0.87). The antioxidant capacities of five major catechins (epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epicatechin, epigallocatechin, and catechin) were determined by online HPLC DPPH radical-scavenging; the antioxidant activity of tea was mainly attributed to the esterified catechins (EGCG or ECG).
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Upregulation of SYF2 in esophageal squamous cell carcinoma promotes tumor cell proliferation and predicts poor prognosis.
Tumour Biol.
PUBLISHED: 05-16-2014
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SYF2, also known as CCNDBP1-interactor or p29, is reported in pre-mRNA splicing and cell cycle progression. However, the role of SYF2 in esophageal squamous cell carcinoma (ESCC) development remains elusive. In the present study, Western blot and immunohistochemistry assays demonstrated that SYF2 was overexpressed in ESCC tumor tissues and cell lines. In addition, immunohistochemistry analysis revealed that SYF2 expression was positively correlated with tumor grade and predicted poor prognosis of ESCC. In vitro studies using serum starvation-refeeding experiment and SYF2-siRNA transfection assay demonstrated that SYF2 expression promoted proliferation of ESCC cells, while SYF2 knockdown led to decreased cell growth rate and colony formation resulted from growth arrest of cell cycle at G0/G1 phase. Furthermore, our results indicated that SYF2 can down-regulate the sensitivity of ESCC cells for cisplatin. Our findings for the first time supported that SYF2 might play an important role in the regulation of ESCC proliferation and would provide a novel therapeutic strategy against human ESCC.
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Ionic liquid-based vacuum microwave-assisted extraction followed by macroporous resin enrichment for the separation of the three glycosides salicin, hyperin and rutin from Populus bark.
Molecules
PUBLISHED: 05-16-2014
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An effective ionic liquid vacuum microwave-assisted method was developed for extraction of the thermo- and oxygen-sensitive glycosides salicin, hyperin and rutin from Populus bark due to the strong solvating effects of ionic liquids on plant cell walls. In this study, [C4mim]BF4 solution was selected as the extracting solution for extraction of the target analytes. After optimization by single factor experiments and response surface methodology, the optimum condition parameters were achieved, which included 1.0 M [C4mim]BF4, 2 h soaking time, -0.08 MPa vacuum, 20 min microwave irradiation time, 400 W microwave irradiation power and 25 mL/g liquid/solid ratio. Under the optimum conditions, higher extraction yields of salicin (35.53 mg/g), hyperin (1.32 mg/g) and rutin (2.40 mg/g) were obtained. Compared with other extraction methods, the developed method provided higher yields of the three target components after a relatively shorter extraction time (20 min). No obvious degradation of the target analytes was observed under the optimum conditions in performed stability studies and the proposed method had a high reproducibility. Meanwhile, after adsorption and desorption on macroporous D101 resin, the target analytes can be effectively separated from the [C4mim]BF4 ionic liquid extraction solution and the yields of salicin, hyperin and rutin were 89%, 82% and 84%, respectively. The recovered [C4mim]BF4 ionic liquid presented a good extraction effect on the three analytes after recycling five times.
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System analysis of LWDH related genes based on text mining in biological networks.
Biomed Res Int
PUBLISHED: 05-15-2014
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Liuwei-dihuang (LWDH) is widely used in traditional Chinese medicine (TCM), but its molecular mechanism about gene interactions is unclear. LWDH genes were extracted from the existing literatures based on text mining technology. To simulate the complex molecular interactions that occur in the whole body, protein-protein interaction networks (PPINs) were constructed and the topological properties of LWDH genes were analyzed. LWDH genes have higher centrality properties and may play important roles in the complex biological network environment. It was also found that the distances within LWDH genes are smaller than expected, which means that the communication of LWDH genes during the biological process is rapid and effectual. At last, a comprehensive network of LWDH genes, including the related drugs and regulatory pathways at both the transcriptional and posttranscriptional levels, was constructed and analyzed. The biological network analysis strategy used in this study may be helpful for the understanding of molecular mechanism of TCM.
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sA population-based study of macular choroidal neovascularization using optical coherence tomography in Eastern China.
Exp Ther Med
PUBLISHED: 05-02-2014
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The aim of the present study was to investigate the pathomorphological and functional variations of choroidal neovascularization (CNV) in age-related macular degeneration (AMD) in a Chinese population using optical coherence tomography (OCT). This population-based study enrolled 59 patients (age, >45 years; eyes, 70) with early and intermediate-stage AMD from Youyi Road Community, Baoshan District, Shanghai, China. Comprehensive standardized ophthalmic examinations included visual acuity, anterior segment analysis using a slit lamp, dilated fundus evaluation by direct ophthalmoscopy, 90D handheld lens analysis, fundus photography, fundus fluorescein angiography (FFA) and fast optic disk scans using OCT. The macular CNV characteristic profiles in early and intermediate-stage AMD were determined by OCT. Data were obtained on the first visit and the follow-up period ranged between 6 and 24 months, where FFA and OCT outcomes of early and intermediate-stage AMD patients were analyzed. Three profiles of early and intermediate-stage AMD were created from the OCT and FFA results, each with a different prognosis. Firstly, drusens with unclear boundaries and evident pigment proliferation, as well as hypofluorescence around the drusens, was observed via FFA. A slight small arch field located in the retinal pigment epithelium (RPE)/choriocapillary layer (CCL) was shown on OCT scans, indicating exudative AMD. Secondly, RPE detachments of >1 pupillary distance, without CNV in the macular area, indicated geographic chorioretinitis atrophy. Finally, drusens with clear boundaries and few pigment proliferations and no certain surrounding fluorescence was observed via FFA, while a clear RPE/CCL band on the OCT scans indicated slow progress. The results of the present study demonstrated that combined OCT and FFA was the most efficient method for identifying CNV and diagnosing AMD. If the two techniques are not available concurrently, then OCT is a safer and more reliable technique to follow-up early and intermediate-stage AMD patients.
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SKF-96365 strongly inhibits voltage-gated sodium current in rat ventricular myocytes.
Pflugers Arch.
PUBLISHED: 05-01-2014
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SKF-96365 (1-(beta-[3-(4-methoxy-phenyl) propoxy]-4-methoxyphenethyl)-1H-imidazole hydrochloride) is a general TRPC channel antagonist commonly used to characterize the potential functions of TRPC channels in cardiovascular system. Recent reports showed that SKF-96365 induced a reduction in cardiac conduction. The present study investigates whether the reduced cardiac conduction caused by SKF-96365 is related to the blockade of voltage-gated sodium current (I Na) in rat ventricular myocytes using the whole-cell patch voltage-clamp technique. It was found that SKF-96365 inhibited I Na in rat ventricular myocytes in a concentration-dependent manner. The compound (1 ?M) negatively shifted the potential of I Na availability by 9.5 mV, increased the closed-state inactivation of I Na, and slowed the recovery of I Na from inactivation. The inhibition of cardiac I Na by SKF-96365 was use-dependent and frequency-dependent, and the IC50 was decreased from 1.36 ?M at 0.5 Hz to 1.03, 0.81, 0.61, 0.56 ?M at 1, 2, 5, 10 Hz, respectively. However, the selective TRPC3 antagonist Pyr3 decreased cardiac I Na by 8.5 % at 10 ?M with a weak use and frequency dependence. These results demonstrate that the TRPC channel antagonist SKF-96365 strongly blocks cardiac I Na in use-dependent and frequency-dependent manners. Caution should be taken for interpreting the alteration of cardiac electrical activity when SKF-96365 is used in native cells as a TRPC antagonist.
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Microwave-assisted simultaneous extraction of luteolin and apigenin from tree peony pod and evaluation of its antioxidant activity.
ScientificWorldJournal
PUBLISHED: 04-28-2014
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An efficient microwave-assisted extraction (MAE) technique was employed in simultaneous extraction of luteolin and apigenin from tree peony pod. The MAE procedure was optimized using response surface methodology (RSM) and compared with other conventional extraction techniques of macerate extraction (ME) and heat reflux extraction (HRE). The optimal conditions of MAE were as follows: employing 70% ethanol volume fraction as solvent, soaking time of 4?h, liquid-solid ratio of 10 (mL/g), microwave irradiation power of 265?W, microwave irradiation time of 9.6?min, and 3 extraction cycles. Under the optimal conditions, 151??g/g luteolin and 104??g/g apigenin were extracted from the tree peony pod. Compared with ME and HRE, MAE gave the highest extraction efficiency. The antioxidant activities of the extracts obtained by MAE, ME, and HRE were evaluated using a 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) free radical-scavenging assay, a ferric reducing antioxidant power assay (FRAP), and a reducing power assay. Meanwhile, the structural changes of the unprocessed and processed tree peony pod samples were analyzed by scanning electron microscopy.
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A graphic method for identification of novel glioma related genes.
Biomed Res Int
PUBLISHED: 04-18-2014
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Glioma, as the most common and lethal intracranial tumor, is a serious disease that causes many deaths every year. Good comprehension of the mechanism underlying this disease is very helpful to design effective treatments. However, up to now, the knowledge of this disease is still limited. It is an important step to understand the mechanism underlying this disease by uncovering its related genes. In this study, a graphic method was proposed to identify novel glioma related genes based on known glioma related genes. A weighted graph was constructed according to the protein-protein interaction information retrieved from STRING and the well-known shortest path algorithm was employed to discover novel genes. The following analysis suggests that some of them are related to the biological process of glioma, proving that our method was effective in identifying novel glioma related genes. We hope that the proposed method would be applied to study other diseases and provide useful information to medical workers, thereby designing effective treatments of different diseases.
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Multifunctional Superamphiphobic TiO2 Nanostructure Surfaces with Facile Wettability and Adhesion Engineering.
Small
PUBLISHED: 04-13-2014
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Compared to conventional top-down photo-cleavage method, a facile bottom-up ink-combination method to in situ and rapidly achieve water wettability and adhesion transition, with a great contrast on the superamphiphobic TiO2 nanostructured film, is described. Moreover, such combination method is suitable for various kinds of superamphiphobic substrate. Oil-based ink covering or removing changes not only the topographical morphology but also surface chemical composition, and these resultant topographical morphology and composition engineering realize the site-selectively switchable wettability varying from superamphiphobicity to amphiphilicity, and water adhesion between sliding superamphiphobicity and sticky superamphiphobicity in micro-scale. Additionally, positive and negative micro-pattern can be achieved by taking advantage of the inherent photocatalytic property of TiO2 with the assistance of anti-UV light ink mask. Finally, the potential applications of the site-selectively sticky superamphiphobic surface were demonstrated. In a proof-of-concept study, the microdroplet manipulation (storage, moving, mixing, and transfer), specific gas sensing, wettability template for positive and negative ZnO patterning, and site-selective cell immobilization have been demonstrated. This study will give an important input to the field of advanced functional material surfaces with special wettability.
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Protein kinases are potential targets to treat inflammatory bowel disease.
World J Gastrointest Pharmacol Ther
PUBLISHED: 04-05-2014
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Protein kinases play a crucial role in the pathogenesis of inflammatory bowel disease (IBD), the two main forms of which are ulcerative colitis and Crohn's disease. In this article, we will review the mechanisms of involvement of protein kinases in the pathogenesis of and intervention against IBD, in terms of their effects on genetics, microbiota, mucous layer and tight junction, and the potential of protein kinases as therapeutic targets against IBD.
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Characteristics and trends in incidence of childhood cancer in Beijing, China, 2000-2009.
Chin. J. Cancer Res.
PUBLISHED: 04-01-2014
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To investigate the characteristics and incidence trends of childhood cancer in Beijing, China, from 2000 to 2009.
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siRNA-mediated silencing of Wnt5a regulates inflammatory responses in atherosclerosis through the MAPK/NF-?B pathways.
Int. J. Mol. Med.
PUBLISHED: 03-17-2014
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Previous studies have demonstrated that the aberrant expression of Wnt5a occurs in atherosclerotic lesions. However, the precise role of Wnt5a in the pathogenesis of atherosclerosis remains largely unknown. The present study was undertaken to determine whether the RNA interference of Wnt5a in vivo by adenovirus (Ad)-mediated small interfering RNA (siRNA) transfection is capable of inhibiting the progression of atherosclerosis. Recombinant adenovirus carrying siRNA targeting Wnt5a (Ad-Wnt5a siRNA) was designed. Male apolipoprotein E-deficient (ApoE(-/-)) mice were fed a high-fat diet to induce the pathogenesis of atherosclerosis. Mice were randomly divided into 3 groups (n=15 in each group): the mock group, which received treatment with phosphate-buffered saline (PBS); the Ad-NC group, which received treatment with Ad-non-specific siRNA; and the Ad-Wnt5a siRNA group, which received treatment with Ad-Wnt5a siRNA. Treatment with Ad-Wnt5a siRNA markedly inhibited the mRNA and protein expression of Wnt5a in the aortic tissues. The knockdown of Wnt5a had no significant effect on blood lipid levels, but it suppressed atherosclerotic development and increased plaque stability, which was determined by hematoxylin and eosin staining, picrosirius red staining and Oil Red O staining. Furthermore, the mRNA and protein expression of inflammatory cytokines, including monocyte chemotactic protein-1 (MCP-1), cyclooxygenase-2 (COX-2), matrix metalloproteinase (MMP)-2 and MMP-9 was significantly downregulated in the Ad-Wnt5a siRNA group. In addition, the knockdown of Wnt5a inhibited the nuclear factor-?B (NF-?B) and mitogen-activated protein kinase (MAPK) signaling pathways. These results demonstrate that Ad-mediated Wnt5a silencing in vivo attenuates the development of atherosclerotic disease by reducing inflammatory mediators involved in the MAPK/NF-?B pathways.
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Duplicated copy of CHRNA7 increases risk and worsens prognosis of COPD and lung cancer.
Eur. J. Hum. Genet.
PUBLISHED: 03-16-2014
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Recent genome-wide association studies implicated that the nicotinic acetylcholine receptors (nAChRs) are common susceptible genes of two contextual diseases: chronic obstructive pulmonary disease (COPD) and lung cancer. We aimed to test whether the copy number variations (CNVs) in nAChRs have hereditary contributions to development of the two diseases. In two, two-stage, case-control studies of southern and eastern Chinese, a common CNV-3956 that duplicates the cholinergic receptor, nicotinic, ?7 (CHRNA7) gene was genotyped in a total of 7880 subjects and its biological phenotype was assessed. The ?4-copy of CNV-3956 increased COPD risk (?4-copy vs 2/3-copy: OR=1.44, 95% CI=1.23-1.68) and caused poor lung function, and it similarly augmented risk (OR=1.49, 95% CI=1.29-1.73) and worsened prognosis (hazard ratio (HR)=1.25, 95% CI=1.07-1.45) of lung cancer. The ?4-copy was estimated to account for 1.56% of COPD heritability and 1.87% of lung cancer heritability, respectively. Phenotypic analysis further showed that the ?4-copy of CNV-3956 improved CHRNA7 expression in vivo and increased the carriers' smoking amount. The CNV-3956 of CHRNA7 contributed to increased risks and poor prognoses of both COPD and lung cancer, and this may be a genetic biomarker of the two diseases.European Journal of Human Genetics advance online publication, 19 November 2014; doi:10.1038/ejhg.2014.229.
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Hemodynamic monitoring and management of patients undergoing high-risk surgery: a survey among Chinese anesthesiologists.
J Biomed Res
PUBLISHED: 02-19-2014
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Hemodynamic monitoring and optimization improve postoperative outcome during high-risk surgery. However, hemodynamic management practices among Chinese anesthesiologists are largely unknown. This study sought to evaluate the current intraoperative hemodynamic management practices for high-risk surgery patients in China. From September 2010 to November 2011, we surveyed anesthesiologists working in the operating rooms of 265 hospitals representing 28 Chinese provinces. All questionnaires were distributed to department chairs of anesthesiology or practicing anesthesiologists. Once completed, the 29-item questionnaires were collected and analyzed. Two hundred and 10 questionnaires from 265 hospitals in China were collected. We found that 91.4% of anesthesiologists monitored invasive arterial pressure, 82.9% monitored central venous pressure (CVP), 13.3% monitored cardiac output (CO), 10.5% monitored mixed venous saturation, and less than 2% monitored pulse pressure variation (PPV) or systolic pressure variation (SPV) during high-risk surgery. The majority (88%) of anesthesiologists relied on clinical experience as an indicator for volume expansion and more than 80% relied on blood pressure, CVP and urine output. Anesthesiologists in China do not own enough attention on hemodynamic parameters such as PPV, SPV and CO during fluid management in high-risk surgical patients. The lack of CO monitoring may be attributed largely to the limited access to technologies, the cost of the devices and the lack of education on how to use them. There is a need for improving access to these technologies as well as an opportunity to create guidelines and education for hemodynamic optimization in China.
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Lattice strain effects on the optical properties of MoS2 nanosheets.
Sci Rep
PUBLISHED: 02-07-2014
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"Strain engineering" in functional materials has been widely explored to tailor the physical properties of electronic materials and improve their electrical and/or optical properties. Here, we exploit both in plane and out of plane uniaxial tensile strains in MoS2 to modulate its band gap and engineer its optical properties. We utilize X-ray diffraction and cross-sectional transmission electron microscopy to quantify the strains in the as-synthesized MoS2 nanosheets and apply measured shifts of Raman-active modes to confirm lattice strain modification of both the out-of-plane and in-plane phonon vibrations of the MoS2 nanosheets. The induced band gap evolution due to in-plane and out-of-plane tensile stresses is validated by photoluminescence (PL) measurements, promising a potential route for unprecedented manipulation of the physical, electrical and optical properties of MoS2.
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Claudin-2 downregulation by KSHV infection is involved in the regulation of endothelial barrier function.
J. Cutan. Pathol.
PUBLISHED: 02-01-2014
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Kaposi sarcoma (KS), caused by the infection of Kaposi sarcoma-associated herpesvirus (KSHV), is a disease manifested mainly by dark purple skin and mouth nodules. Cancer care studies showed that co-infection of KSHV and human immunodeficiency virus (HIV) was able to increase the patients' survival, but the underlying mechanisms are still elusive.
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Deletion of glucose oxidase changes the pattern of organic acid production in Aspergillus carbonarius.
AMB Express
PUBLISHED: 01-01-2014
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Aspergillus carbonarius has potential as a cell factory for the production of different organic acids. At pH 5.5, A.carbonarius accumulates high amounts of gluconic acid when it grows on glucose based medium whereas at low pH, it produces citric acid. The conversion of glucose to gluconic acid is carried out by secretion of the enzyme, glucose oxidase. In this work, the gene encoding glucose oxidase was identified and deleted from A. carbonarius with the aim of changing the carbon flux towards other organic acids. The effect of genetic engineering was examined by testing glucose oxidase deficient (?gox) mutants for the production of different organic acids in a defined production medium. The results obtained showed that the gluconic acid accumulation was completely inhibited and increased amounts of citric acid, oxalic acid and malic acid were observed in the ?gox mutants.
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Double CEBPA mutations are prognostically favorable in non-M3 acute myeloid leukemia patients with wild-type NPM1 and FLT3-ITD.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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This study is aimed to investigate the pattern of CEBPA mutations and its clinical significance in Chinese non-M3 acute myeloid leukemia (AML) patients. The entire coding region of CEBPA gene was amplified by PCR and then sequenced in samples from 233 non-M3 AML patients. Fifty mutations were identified in 37 (15.8%) patients with eleven (4.7%) double mutated CEBPA (dmCEBPA) and twenty-six (11.1%) single mutated CEBPA (smCEBPA). dmCEBPA was exclusively observed in M1 and M2 subtypes of FAB classification (P = 0.008), whereas smCEBPA occurred in almost all subtypes (P = 0.401). Patients with dmCEBPA had significantly younger age and higher WBC counts than those with wtCEBPA (P = 0.016 and 0.043, respectively). Both dmCEBPA and smCEBPA were mainly present in cytogenetically normal patients. Patients with dmCEBPA achieved higher rate of complete (CR) than wtCEBPA patients (88% vs. 51%, P = 0.037), whereas smCEBPA and wtCEBPA groups are similar (47% vs. 51%, P = 0.810). Patients with dmCEBPA had a superior overall survival (OS) compared with patients with wtCEBPA (P = 0.033), whereas patients with smCEBPA had a similar OS as patients with wtCEBPA (P = 0.976). dmCEBPA but not smCEBPA was also associated with favorable outcome in patients with wild-type NPM1 and FLT3-ITD (NPM1(wt)FLT3-ITD(wt) ). Our data confirm that dmCEBPA but not smCEBPA is prognostically favorable in NPM1(wt)FLT3-ITD(wt) AML, and suggest that the entity AML with mutated CEBPA should be definitely designated as AML with dmCEBPA in WHO classification and smCEBPA should be excluded from the favorable risk of molecular abnormalities.
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Exogenous trehalose largely alleviates ionic unbalance, ROS burst, and PCD occurrence induced by high salinity in Arabidopsis seedlings.
Front Plant Sci
PUBLISHED: 01-01-2014
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Trehalose (Tre) has been reported to play a critical role in plant response to salinity and the involved mechanisms remain to be investigated in detail. Here, the putative roles of Tre in regulation of ionic balance, cellular redox state, cell death were studied in Arabidopsis under high salt condition. Our results found that the salt-induced restrictions on both vegetative and reproductive growth in salt-stressed plants were largely alleviated by exogenous supply with Tre. The microprobe analysis of ionic dynamics in the leaf and stem of florescence highlighted the Tre ability to retain K and K/Na ratio in plant tissues to improve salt tolerance. The flow cytometry assay of cellular levels of reactive oxygen species and programmed cell death displayed that Tre was able to antagonized salt-induced damages in redox state and cell death and sucrose did not play the same role with Tre. By comparing ionic distribution in leaf and inflorescence stem (IS), we found that Tre was able to restrict Na transportation to IS from leaves since that the ratio of Na accumulation in leaves relative to IS was largely improved due to Tre. The marked decrease of Na ion and improved sucrose level in IS might account for the promoted floral growth when Tre was included in the saline solution. At the same time, endogenous soluble sugars and antioxidant enzyme activities in the salt-stressed plants were also elevated by Tre to counteract high salt stress. We concluded that Tre could improve Arabidopsis salt resistance with respect to biomass accumulation and floral transition in the means of regulating plant redox state, cell death, and ionic distribution.
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Growth Hormone-Regulated mRNAs and miRNAs in Chicken Hepatocytes.
PLoS ONE
PUBLISHED: 01-01-2014
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Growth hormone (GH) is a key regulatory factor in animal growth, development and metabolism. Based on the expression level of the GH receptor, the chicken liver is a major target organ of GH, but the biological effects of GH on the chicken liver are not fully understood. In this work we identified mRNAs and miRNAs that are regulated by GH in primary hepatocytes from female chickens through RNA-seq, and analyzed the functional relevance of these mRNAs and miRNAs through GO enrichment analysis and miRNA target prediction. A total of 164 mRNAs were found to be differentially expressed between GH-treated and control chicken hepatocytes, of which 112 were up-regulated and 52 were down-regulated by GH. A total of 225 chicken miRNAs were identified by the RNA-Seq analysis. Among these miRNAs 16 were up-regulated and 1 miRNA was down-regulated by GH. The GH-regulated mRNAs were mainly involved in growth and metabolism. Most of the GH-upregulated or GH-downregulated miRNAs were predicted to target the GH-downregulated or GH-upregulated mRNAs, respectively, involved in lipid metabolism. This study reveals that GH regulates the expression of many mRNAs involved in metabolism in female chicken hepatocytes, which suggests that GH plays an important role in regulating liver metabolism in female chickens. The results of this study also support the hypothesis that GH regulates lipid metabolism in chicken liver in part by regulating the expression of miRNAs that target the mRNAs involved in lipid metabolism.
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Maternal socioeconomic status and the risk of congenital heart defects in offspring: a meta-analysis of 33 studies.
PLoS ONE
PUBLISHED: 01-01-2014
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We conducted this meta-analysis to address the open question of a possible association between maternal socioeconomic status and congenital heart defects (CHDs).
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Triggering the succinate receptor GPR91 enhances pressure overload-induced right ventricular hypertrophy.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Pulmonary arterial hypertension (PAH) leads to pressure overload in the right ventricle (RV) and induces right ventricular hypertrophy (RVH). GPR91 is an orphan G-protein-coupled receptor (GPCR) that has been characterized as a receptor for succinate, which increases in RVH; however, its role remains unknown.
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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
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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.
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A Newfound association between MDC1 functional polymorphism and lung cancer risk in Chinese.
PLoS ONE
PUBLISHED: 01-01-2014
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Mediator of DNA damage checkpoint protein 1 (MDC1) plays an early and core role in Double-Strand Break Repair (DDR) and ataxia telangiectasia-mutated (ATM) mediated response to DNA double-strand breaks (DSBs), and thus involves the pathogenesis of several DNA damage-related diseases such as cancer. We hypothesized that the single nucleotide polymorphisms (SNPs) of MDC1 which have potencies on affecting MDC1 expression or function were associated with risk of lung cancer. In a two-stage case-control study, we tested the association between 5 putatively functional SNPs of MDC1 and lung cancer risk in a southern Chinese population, and validated the promising association in an eastern Chinese population. We found the SNP rs4713354A>C that is located in the 5'-untranslated region of MDC1 was significantly associated with lung cancer risk in both populations (P = 0.024), with an odds ratio as 1.23(95% confidence interval ?= 1.35-1.26) for the rs4713354C (CA+CC) genotypes compared to the rs4713354AA genotype. However, no significant association was observed between other SNPs and lung cancer risk. The gene-based analysis rested with these SNPs suggested the MDC1 as a susceptible gene for lung cancer (P = 0.009). Moreover, by querying the gene expression database, we further found that the rs4713354C genotypes confer a significantly lower mRNA expression of MDC1 than the rs4713354AA genotype in 260 cases of lymphoblastoid cells (P = 0.002). Our data suggested that the SNP rs4713354A>C of MDC1 may be a functional genetic biomarker for susceptibility to lung cancer in Chinese.
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Sildenefil increases connexin 40 in smooth muscle cells through activation of BMP pathways in pulmonary arterial hypertension.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Pulmonary arterial hypertension (PAH) is a cardiovascular disorder associated with enhanced proliferation and suppressed apoptosis of pulmonary arterial smooth muscle cells (PASMCs). The sildenafil can regulate the Connexin (Cx) 43 in the PASMCs and thus inhibit the PASMCs proliferation and the remodeling of pulmonary arterial. However, how sildenafil exert regulation in the Cx40 in the PASMCs in PAH remains unclear.
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High expression of GPER1, EGFR and CXCR1 is associated with lymph node metastasis in papillary thyroid carcinoma.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Clinical and epidemiological studies have shown that estrogen may be involved in the development and progression of papillary thyroid carcinoma (PTC). G protein-coupled estrogen receptor 1 (GPER1) is a novel seven-transmembrane estrogen receptor that functions alongside traditional nuclear estrogen receptors (ERs) to regulate the cellular responses to estrogen. The purpose of this study was to examine GPER1, EGFR and CXCR1 expression in PTC and to assess the association of their expression with clinicopathological indicators. GPER1, EGFR and CXCR1 protein expression in 129 PTCs, 61 nodular hyperplasia and 118 normal thyroid tissue specimens were analyzed using immunohistochemistry. The protein expression levels of these three molecules were up-regulated in PTCs. High protein expression of GPER1, EGFR and CXCR1 was significantly correlated with lymph node metastasis (LNM) (P ? 0.001). Furthermore, GPER1, EGFR and CXCR1 protein expression were correlated with one another. Concomitant high expression of these molecules had stronger correlation with LNM than did each alone (P = 0.002 for GPER1/EGFR, P = 0.013 for GPER1/CXCR1, P = 0.018 for EGFR/CXCR1 and P < 0.001 for GPER1/EGFR/CXCR1). Additionally, GPER1, EGFR and CXCR1 mRNA expression was assessed in 30 PTCs, 10 nodular hyperplasia and 10 normal thyroid tissue specimens using real-time RT-PCR. GPER1, EGFR and CXCR1 mRNA expression levels were up-regulated in PTCs, and high mRNA expression of GPER1, EGFR and CXCR1 was significantly correlated with LNM (P < 0.001 for all these three molecules). These results demonstrated that the evaluation of GPER1, EGFR and CXCR1 expression in PTC may be useful in predicting the risk of LNM.
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Predicting disease-related proteins based on clique backbone in protein-protein interaction network.
Int. J. Biol. Sci.
PUBLISHED: 01-01-2014
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Network biology integrates different kinds of data, including physical or functional networks and disease gene sets, to interpret human disease. A clique (maximal complete subgraph) in a protein-protein interaction network is a topological module and possesses inherently biological significance. A disease-related clique possibly associates with complex diseases. Fully identifying disease components in a clique is conductive to uncovering disease mechanisms. This paper proposes an approach of predicting disease proteins based on cliques in a protein-protein interaction network. To tolerate false positive and negative interactions in protein networks, extending cliques and scoring predicted disease proteins with gene ontology terms are introduced to the clique-based method. Precisions of predicted disease proteins are verified by disease phenotypes and steadily keep to more than 95%. The predicted disease proteins associated with cliques can partly complement mapping between genotype and phenotype, and provide clues for understanding the pathogenesis of serious diseases.
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Overexpression of HIF-1?, metallothionein and SLUG is associated with high TNM stage and lymph node metastasis in papillary thyroid carcinoma.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Hypoxia inducible factor-1? (HIF-1?) is upregulated by hypoxia, and involved in tumor growth and metastasis in many malignant tumors including papillary thyroid carcinoma (PTC). Metallothionein (MT) is a group of small molecular weight cysteine-rich proteins with a broad variety of functions. SLUG is a member of SNAIL superfamily of zinc finger transcriptional factors implicated in epithelial-mesenchymal transition (EMT). The purpose of this study was to examine HIF-1?, MT and SLUG expression in PTC and assess association of their expression with clinicopathological indicators. HIF-1?, MT and SLUG protein expression in 129 PTCs, 61 nodular hyperplasia and 118 normal thyroid tissue specimens were analyzed using immunohistochemistry. The protein expression levels of these three molecules were up-regulated in PTCs. High protein expression of HIF-1?, MT and SLUG was significantly correlated with high TNM stage (P=0.003, 0.002, 0.024, respectively) and lymph node metastasis (LNM) (P<0.001 for all three molecules). Furthermore, HIF-1?, MT and SLUG protein expression were correlated with one another. Concomitant high expression of any two of these three molecules had stronger correlation with high TNM stage (P?0.001 for HIF-1?/MT, MT/SLUG and HIF-1?/SLUG) and LNM (P=0.008, 0.002, 0.019 for HIF-1?/MT, MT/SLUG and HIF-1?/SLUG, respectively) than did each alone, and concomitant high expression of all these three molecules is significantly associated with high TNM stage and LNM as compared with cases not showing such expression (P<0.001). These results demonstrated that the evaluation of HIF-1?, MT and SLUG expression in PTC may be useful in predicting the risk of LNM and high TNM stage.
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A conformational restriction in influenza A virus neuraminidase binding site by R152 caused the combinational effect of I222T with H274Y on oseltamivir resistance.
Antimicrob. Agents Chemother.
PUBLISHED: 12-23-2013
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The I222K, I222R and I222T substitutions in neuraminidase (NA) were currently found in clinically-derived 2009 pandemic H1N1 viruses with altered susceptibilities to NA inhibitors (NAIs). The effects of these substitutions together with the most frequently observed resistance related substitution, H274Y, on viral fitness and resistance mechanism were further investigated in this study. Reduced sensitivities to oseltamivir were observed in all three mutants. Furthermore, I222K and I222T substitutions had combinational effect of further increasing resistance in the presence of H274Y, which might result from a conformational restriction in NA binding-site. Especially, by using the molecular dynamics simulation, R152, the neighbor of T222, was observed to translate to a closer position to T222 and resulted in the narrowing down of binding pocket, which just subtended the residue substitution of H274Y. Moreover, significantly attenuated NA function and viral growth abilities were found in I222K+H274Y mutant, while I222T+H274Y mutant exhibited a slightly delayed growth but with similar peak viral titer as that of wild-type virus in MDCK cells. Relatively growth advantage of I222T mutant versus I222K and higher frequency of I222T emerging in N1 subtype influenza viruses raised the concerns to closely monitoring the dual substitutions of I222T and H274Y.
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[Selection pressure analysis of H3N2 influenza virus from China between 1992 and 2012].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
PUBLISHED: 12-11-2013
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In order to investigate the relationship between selection pressure and the prevalence of antigenic clusters, we sequenced and analyzed the H3N2 influenza virus from China between 1992 and 2012.
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[The evaluation of SCI by TMS-MEP and its forensic significance].
Fa Yi Xue Za Zhi
PUBLISHED: 12-06-2013
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To find an objective and accurate examination for evaluation of spinal cord injury (SCI) in forensic clinical medicine.
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Allogeneic platelet transfusions prevent murine T cell-mediated immune thrombocytopenia (ITP).
Blood
PUBLISHED: 11-20-2013
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Platelet transfusions are life saving treatments for many patients with thrombocytopenia, however, their use is generally discouraged in the autoimmune disorder immune thrombocytopenia (ITP). We examined whether allogeneic platelet major histocompatibility complex (MHC) class I transfusions affected anti-platelet CD61-induced ITP. BALB/c CD61 knockout (KO) mice (CD61-/H-2(d)) were immunized against platelets from either wildtype syngeneic BALB/c (CD61+/ H-2(d)) or allogeneic C57BL/6 (CD61+/ H-2(b)) or C57BL/6 CD61 KO (CD61-/ H-2(b)) mice and their splenocytes were transferred into severe combined immunodeficient (SCID) mice to induce ITP. When non-depleted splenocytes were transferred to induce antibody-mediated ITP, both CD61+ platelet immunizations generated immunity that caused thrombocytopenia independently of allo-MHC molecules. In contrast, when B cell-depleted splenocytes were transferred to induce T cell-mediated ITP, transfer of allogeneic MHC-immunized splenocytes completely prevented CD61-induced ITP development. In addition, allogeneic platelet transfusions into SCID mice with established CD61-induced ITP rescued the thrombocytopenia. Compared with thrombocytopenic mice, bone marrow histology in the rescued mice showed normalized megakaryocyte morphology and in vitro CD61-specific T cell cytotoxicity was significantly suppressed. These results indicate that antibody-mediated ITP is resistant to allogeneic platelet transfusions whereas the T cell-mediated form of the disease is susceptible suggesting that transfusion therapy may be beneficial in antibody-negative ITP.
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Synthesis and characterization of chitosan quaternary ammonium salt and its application as drug carrier for ribavirin.
Drug Deliv
PUBLISHED: 11-12-2013
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Abstract N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC) is hydro-soluble chitosan (CS) derivative, which can be obtained by the reaction between epoxypropyl trimethyl ammonium chloride (ETA) and CS. The preparation parameters for the synthesis of HTCC were optimized by orthogonal experimental design. ETA was successfully grafted into the free amino group of CS. Grafting of ETA with CS had great effect on the crystal structure of HTCC, which was confirmed by the XRD results. HTCC displayed higher capability to form nanoparticles by crosslinking with negatively charged sodium tripolyphosphate (TPP). Ribavrin- (RIV-) loaded HTCC nanoparticles were positively charged and were spherical in shape with average particle size of 200?nm. More efficient drug encapsulation efficiency and loading capacity were obtained for HTCC in comparison with CS, however, HTCC nanoparticles displayed faster release rate due to its hydro-soluble properties. The results suggest that HTCC is a promising CS derivative for the encapsulation of hydrophilic drugs in obtaining sustained release of drugs.
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miR-181b promotes cell proliferation and reduces apoptosis by repressing the expression of adenylyl cyclase 9 (AC9) in cervical cancer cells.
FEBS Lett.
PUBLISHED: 11-02-2013
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MicroRNAs are a class of small, endogenous, non-coding RNAs that function as post-transcriptional regulators. In this study, we found that miR-181b promoted cell proliferation and inhibited cell apoptosis in cervical cancer cells. And we validated a new miR-181b target gene, adenylyl cyclase 9 (AC9). miR-181b restricted cAMP production by post-transcriptionally downregulating AC9 expression. Phenotypic experiments indicated that miR-181b and AC9 exerted opposite effects on cell proliferation and apoptosis.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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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.