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Find video protocols related to scientific articles indexed in Pubmed.
Interaction of a two-level atom with single-mode optical field beyond the rotating wave approximation.
Opt Express
PUBLISHED: 11-18-2014
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One of the simplest models involving the atom-field interaction is the coupling of a single two-level atom with single-mode optical field. Under the rotating wave approximation, this problem is reduced to a form that can be solved exactly. But the approximation is only valid when the two levels are resonant or nearly resonant with the applied electromagnetic radiation. Here we present an analytical solution without the rotating wave approximation and applicable to general atom-field interaction far away from the resonance. We find that there exists remarkable influence of the initial phase of optical field on the Rabi oscillations and Rabi splitting, and this issue cannot be explored in the context of the rotating wave approximation. Due to the retention of the counter-rotating terms, higher-order harmonic appears during the Rabi splitting. The analytical solution suggests a way to regulate and control the quantum dynamics of a two-level atom and allows for exploring more essential features of the atom-field interaction.
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Giant enhancement of second harmonic generation by engineering double plasmonic resonances at nanoscale.
Opt Express
PUBLISHED: 11-18-2014
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We have investigated second harmonic generation (SHG) from Ag-coated LiNbO3 (LN) core-shell nanocuboids and found that giant SHG can occur via deliberately designed double plasmonic resonances. By controlling the aspect ratio, we can tune fundamental wave (FW) and SHG signal to match the longitudinal and transverse plasmonic modes simultaneously, and achieve giant enhancement of SHG by 3 × 105 in comparison to a bare LN nanocuboid and by about one order of magnitude to the case adopting only single plasmonic resonance. The underlying key physics is that the double-resonance nanoparticle enables greatly enhanced trapping and harvesting of incident FW energy, efficient internal transfer of optical energy from FW to the SHG signal, and much improved power to transport the SHG energy from the nanoparticle to the far-field region. The proposed double-resonance nanostructure can serve as an efficient subwavelength coherent light source through SHG and enable flexible engineering of light-matter interaction at nanoscale.
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Staphylococcal enterotoxin B administration during pregnancy imprints the increased CD4:CD8 T cell ratio in the peripheral blood from the neonatal to adult offspring rats.
J. Med. Microbiol.
PUBLISHED: 11-07-2014
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Our previous study demonstrated that SEB administration during pregnancy could alter the percentage of T cells subpopulation in the thymus of the neonatal rats, however, it is little known about the effect of maternal SEB administration during pregnancy on T cells subpopulation in the peripheral blood of the offspring rats. In the present study, pregnant rats at gestational day (GD) 16 were intravenously injected with 15 ?g SEB. The present study revealed that the prenatal exposure of SEB significantly decreased the percentages of CD8 T cells in the peripheral blood of both the neonatal rats in the fifth day after delivery and the adult offspring rats, and significantly increased the percentage of CD4 T cells as well as the ratios of CD4 to CD8 T cells in both the neonatal and adult offspring rats. The prenatal exposure of SEB significantly decreased the expression levels of IL-4 and IFN-? in the plasma of the neonatal and adult offspring rats. Furthermore, SEB restimulation significantly increased the percentage of CD8 T cells and significantly decreased the percentage of CD4 T cells. These data suggested the prenatal exposure of SEB was able to imprint the increased CD4:CD8 T cell ratio in the peripheral blood from the neonate to adulthood through the decreased CD8 T cells and the increased CD4 T cells, and altered the response characteristics of CD4 and CD8 T cells to secondary SEB administration in the peripheral blood of the adult offspring rats.
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Synthesis and Antibacterial Activities of Yanglingmycin Analogues.
Chem. Pharm. Bull.
PUBLISHED: 10-31-2014
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The synthesis of Yanglingmycin and its enantiomer, along with eighteen Yanglingmycin analogues is reported. The structures were confirmed mainly by analyses of NMR spectral data. Antibacterial activity assays showed that Yanglingmycin and some of its analogues exhibited significant antibacterial activities against two important agricultural pathogenic bacteria, Ralstonia solanacearum and Pseudomonas syringae pv. actinidiae, with MIC values ranging from 3.91 to 15.62 ?g/mL. The antibacterial activities exhibited by Yanglingmycin and its analogues are promising, suggesting potential in the development of compounds for novel bactericides.
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[Effect of climate change on net primary productivity of Korean pine (Pinus koraiensis) at different successional stages of broad-leaved Korean pine forest].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 10-28-2014
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Pinus koraiensis in broad-leaved Korean pine forests of Changbai Mountain at different successional stages (secondary poplar-birch forest, secondary coniferous and broad-leaved forest and the primitive Korean pine forest) were selected in this paper as the research objects. In this research, the annual growth of net primary productivity (NPP) (1921-2006) of P. koraiensis was obtained by combining the tree-ring chronology and relative growth formulae, the correlation between NPP of P. koraiensis and climatic factors was developed, and the annual growth of NPP of P. koraiensis at different successional stages in relation to climatic variation within different climate periods were analyzed. The results showed that, in the research period, the correlations between climatic factors and NPP of P. koraiensis at different successional stages were different. With increasing the temperature, the correlations between NPP of P. koraiensis in the secondary poplar-birch forest and the minimum temperatures of previous and current growing seasons changed from being significantly negative to being significantly positive. The positive correlation between NPP of P. koraiensis in the secondary coniferous and broad-leaved forest and the minimum temperature in current spring changed into significantly positive correlation between NPP of P. koraiensis and the temperatures in previous and current growing seasons. The climatic factors had a stronger hysteresis effect on NPP of P. koraiensis in the secondary coniferous and broad-leaved forest, but NPP of P. koraiensis in the primitive Korean pine forest had weaker correlation with temperature but stronger positive correlation with the precipitation of previous growing season. The increases of minimum and mean temperatures were obvious, but no significant variations of the maximum temperature and precipitation were observed at our site. The climatic variation facilitated the increase of the NPP of P. koraiensis in the secondary poplar-birch forest at the initial successional stage and in secondary coniferous and broad-leaved forest at the intermediate successional stage, and this effect was especially obvious for the secondary coniferous and broad-leaved forest, but very small for the primitive Korean pine forest which was at the climax phase.
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Mesoporous Bi2S3 nanorods with graphene-assistance as low-cost counter-electrode materials in dye-sensitized solar cells.
Nanoscale
PUBLISHED: 10-24-2014
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In this work, we report the synthesis of mesoporous Bi2S3 nanorods under hydrothermal conditions without additives, and investigated their catalytic activities as the CE in DSCs by I-V curves and tested conversion efficiency. To further improve their power conversion efficiency, we added different amounts of reduced graphene by simple physical mixing. With the addition of 9 wt% reduced graphene (rGO), the short-circuit current density, open-circuit voltage and fill factor were Jsc = 15.33 mA cm(-2), Voc = 0.74 V and FF = 0.609. More importantly, the conversion efficiency reached 6.91%, which is slightly inferior to the commercial Pt counter electrode (7.44%). Compared to the conventional Pt counter electrodes of solar cells, this new material has the advantages of low-cost, facile synthesis and high efficiency with graphene assistance. To the best of our knowledge, this Bi2S3 + 9 wt% rGO system has the best performance ever recorded in all Bi2S3-based CEs in the DSCs system.
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Anti-inflammatory Diterpenoids from the Root Bark of Acanthopanax gracilistylus.
J. Nat. Prod.
PUBLISHED: 10-23-2014
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Five new ent-pimarane (1-3, 7, and 8) and three new ent-kaurane diterpenoids (4-6) and a new oleanane triterpene acid (9), together with 22 known compounds, were isolated from the root bark of the medicinal herb Acanthopanax gracilistylus. The structures of 1-9 were established based on the interpretation of high-resolution MS and 1D- and 2D-NMR data. The absolute configurations of 7 and 11 were determined by single-crystal X-ray diffraction and electronic circular dichroism analysis. Compounds 7 and 8 represent rare naturally occurring structures based on the devinyl ent-pimarane skeleton. Compounds 3, 10, 14, 16, and 17 exhibited potent inhibitory effects on the release of interleukin-1? (IL-1?), interleukin-8 (IL-8), and tumor necrosis factor (TNF-?) in lipopolysaccharide-stimulated peripheral blood mononuclear cells.
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Highly efficient second harmonic generation of a light carrying orbital angular momentum in an external cavity.
Opt Express
PUBLISHED: 10-17-2014
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Traditional methods for generating a light carrying orbital angular momentum (OAM) include the use of holographic diffraction gratings, vortex phase plates and spatial light modulators. Here we report a new method for highly efficient second-harmonic generation (SHG) of a light with OAM. By properly aligning an external cavity that contains a quasi-phase matching nonlinear crystal and pumping it with a light carrying OAM, mode matching between the pump light and the cavity's higher order Laguerre-Gaussian (LG) mode is achieved, SHG with a conversion efficiency of up to 10.3% is obtained. We have demonstrated for the first time that the cavity can stably operate at its higher order LG mode similar to that of a Gaussian mode. The second harmonic generated light has an OAM value that is double with respected to the OAM value of the pump light. The parameters that affect the beam quality and conversion efficiency are discussed in detail. Our work opens a brand new field in laser optics and makes the first step toward high efficiency processing using a light carrying OAM.
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Orbital angular momentum light frequency conversion and interference with quasi-phase matching crystals.
Opt Express
PUBLISHED: 10-17-2014
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Light with helical phase structures, carrying quantized orbital angular momentum (OAM), has many applications in both classical and quantum optics, such as high-capacity optical communications and quantum information processing. Frequency conversion is a basic technique to expand the frequency range of the fundamental light. The frequency conversion of OAM-carrying light gives rise to new physics and applications such as up-conversion detection of images and generation of high dimensional OAM entanglements. Quasi-phase matching (QPM) nonlinear crystals are good candidates for frequency conversion, particularly due to their high-valued effective nonlinear coefficients and no walk-off effect. Here we report the first experimental second-harmonic generation (SHG) of an OAM-carried light with a QPM crystal, where a UV light with OAM of 100? is generated. OAM conservation is verified using a specially designed interferometer. With a pump beam carrying an OAM superposition of opposite sign, we observe interesting interference phenomena in the SHG light; specifically, a photonics gear-like structure is obtained that gives direct evidence of OAM conservation, which will be very useful for ultra-sensitive angular measurements. Besides, we also develop a theory to reveal the underlying physics of the phenomena. The methods and theoretical analysis shown here are also applicable to other frequency conversion processes, such as sum frequency generation and difference-frequency generation, and may also be generalized to the quantum regime for single photons.
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Noise characterization of broadband fiber Cherenkov radiation as a visible-wavelength source for optical coherence tomography and two-photon fluorescence microscopy.
Opt Express
PUBLISHED: 10-17-2014
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Optical sources in the visible region immediately adjacent to the near-infrared biological optical window are preferred in imaging techniques such as spectroscopic optical coherence tomography of endogenous absorptive molecules and two-photon fluorescence microscopy of intrinsic fluorophores. However, existing sources based on fiber supercontinuum generation are known to have high relative intensity noise and low spectral coherence, which may degrade imaging performance. Here we compare the optical noise and pulse compressibility of three high-power fiber Cherenkov radiation sources developed recently, and evaluate their potential to replace the existing supercontinuum sources in these imaging techniques.
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Stability in computed optical interferometric tomography (Part II): in vivo stability assessment.
Opt Express
PUBLISHED: 10-17-2014
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Stability is of utmost importance to a wide range of phase-sensitive processing techniques. In Doppler optical coherence tomography and optical coherence elastography, in addition to defocus and aberration correction techniques such as interferometric synthetic aperture microscopy and computational/digital adaptive optics, a precise understanding of the system and sample stability helps to guide the system design and choice of imaging parameters. This article focuses on methods to accurately and quantitatively measure the stability of an imaging configuration in vivo. These methods are capable of partially decoupling axial from transverse motion and are compared against the stability requirements for computed optical interferometric tomography laid out in the first part of this article.
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Stability in computed optical interferometric tomography (Part I): Stability requirements.
Opt Express
PUBLISHED: 10-17-2014
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As imaging systems become more advanced and acquire data at faster rates, increasingly dynamic samples can be imaged without concern of motion artifacts. For optical interferometric techniques such as optical coherence tomography, it often follows that initially, only amplitude-based data are utilized due to unstable or unreliable phase measurements. As systems progress, stable phase maps can also be acquired, enabling more advanced, phase-dependent post-processing techniques. Here we report an investigation of the stability requirements for a class of phase-dependent post-processing techniques - numerical defocus and aberration correction with further extensions to techniques such as Doppler, phase-variance, and optical coherence elastography. Mathematical analyses and numerical simulations over a variety of instabilities are supported by experimental investigations.
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Androgen receptor promotes gastric cancer cell migration and invasion via AKT-phosphorylation dependent upregulation of matrix metalloproteinase 9.
Oncotarget
PUBLISHED: 10-11-2014
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Androgen receptor (AR) plays an important role in many kinds of cancers. However, the molecular mechanisms of AR in gastric cancer (GC) are poorly characterized. Here, we investigated the role of AR in GC cell migration, invasion and metastatic potential. Our data showed that AR expression was positively correlated with lymph node metastasis and late TNM stages. These findings were accompanied by activation of AKT and upregulation of matrix metalloproteinase 9 (MMP9). AR overexpression induced increases in GC cell migration, invasion and proliferation in vitro and in vivo. These effects were attenuated by inhibition of AKT, AR and MMP9. AR overexpression upregulated MMP9 protein levels, whereas this effect was counteracted by AR siRNA. Inhibition of AKT by siRNA or an inhibitor (MK-2206 2HC) decreased AR protein expression in both stably transfected and parental SGC-7901 cells. Luciferase reporter and chromatin immunoprecipitation assays demonstrated that AR bound to the AR-binding sites of the MMP9 promoter. In summary, AR overexpression induced by AKT phosphorylation upregulated MMP9 by binding to its promoter region to promote gastric carcinogenesis. The AKT/AR/MMP9 pathway plays an important role in GC metastasis and may be a novel therapeutic target for GC treatment.
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[Study on safety of Tibetan medicine zuotai and preliminary study on clinical safety of its compound dangzuo].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-04-2014
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Zuotai (gTso thal) is a typical representative of Tibetan medicines containing heavy metals, but there is still lack of modem safety evaluation data so far. In this study, acute toxicity test, sub-acute toxicity test, one-time administration mercury distribution experiment, long-term mercury accumulative toxicity experiment and preliminary study on clinical safety of Compound Dangzuo were conducted in the hope of obtain the medicinal safety data of Zuotai. In the acute toxicity test, half of KM mice given the lethal dose of Zuotai were not died or poisoned, and LD50 was not found. The maximum tolerated dose of Zuotai was 80 g x kg(-1). In the subacute toxicity test, Zuotai could reduce ALT, AST, Crea levels in serums under low dose (13.34 mg x kg(-1) x d(-1)) and medium dose (53.36 mg x kg(-1) x d(-1)), with significant difference under low dose, and increase the levels of ALT, AST, MDA, Crea in serums under high dose (2 000 mg x kg(-1) x d(-1)); besides, the levels of BUN and GSH in serums reduced with the increase in dose of Zuotai, indicating a significant dose-effect relationship. In the one-time administration distribution experiment, the content of mercury in rat kidney, liver and lung increased after the one-time administration with Zuotai, with a significant dose-dependent relationship in kidney. In the long-term mercury accumulative toxicity experiment, KM mice were administered with equivalent doses of Zuotai for 4.5 months and then stopped drug administration for 1.5 months. Since the 2.5th month, they showed significant mercury accumulation in kidney, which gradually reduced after drug withdrawal, without significant change in mercury content in liver, spleen and brain and ALT, AST, TBIL, BUN and Crea in serum. At the 4.5th month after drug administration, KM mice showed slight structural changes in kidney, liver and spleen tissues, and gradually recovered to normal after drug withdrawal. Besides, no significant difference in weight gain was found between the Zuotai group and the control group. According to the findings of the clinical safety study of Dangzuo, after subjects administered Dangzuo under clinical dose for one month, their serum biochemical indicators, blood routine indicators and urine routine indicators showed no significant adverse change. This study proved that traditional Tibetan medicine Zuotai was slightly toxic, with a better safety in clinical combined administration and no adverse effects on bodies under the clinical dose and clinical medication cycle. However, long-term high-dose administration of Zuotai may have a certain effect on kidney.
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The protective effect of ozone oxidative preconditioning against hypoxia/reoxygenation injury in rat kidney cells.
Ren Fail
PUBLISHED: 09-24-2014
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Abstract Ozone (O3) has been viewed as a novel treatment for different diseases in these years and oxidative stress and apoptosis play a key role in the pathogenesis of kidney diseases including renal ischemia and reperfusion (I/R). In the present study, we investigated the role of ozone oxidative preconditioning (OzoneOP) in attenuating oxidative stress and apoptosis in a hypoxia/reoxygenation (H/R) injury model using rat kidney cells. We induced H/R injury in kidney cells treated with or without OzoneOP. Oxidative stress parameters such as superoxide dismutase (SOD), malondialdehyde (MDA) and lactate dehydrogenase (LDH) were determined, as well as some apoptotic proteins. We observed that oxidative stress and apoptosis were increased in H/R group compared to OzoneOP group; however, these changes were significantly decreased by the treatment with OzoneOP. We concluded that OzoneOP can protect the kidney cells against H/R injury and its mechanism may be through the reduction of oxidative stress and apoptosis.
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Picroside II decreases the development of fibrosis induced by ischemia/reperfusion injury in rats.
Ren Fail
PUBLISHED: 09-24-2014
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In kidney transplantation, renal ischemia and reperfusion injury was one of the leading factors to the development of renal fibrosis, which was the main cause of graft loss. The fibrogenic changes were associated with the long term inflammation elicited by ischemia and reperfusion injury. In the present study, we investigated the role of the Picroside II, the main active constituents of the extract of picrorrhiza scrophulariiflora roots, in attenuating renal fibrosis in a renal ischemia and reperfusion injury model. We induced ischemia and reperfusion injury in kidneys treated with or without Picroside II. We observed that inflammation and tissue fibrosis were increased in ischemia and reperfusion injury group compared to Picroside II group, however, these changes were significantly decreased by the treatment with Picroside II. We concluded that Picroside II can protect the ischemic kidney against renal fibrosis and its mechanism may be through the inhibition of the long term inflammation.
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Computed optical interferometric tomography for high-speed volumetric cellular imaging.
Biomed Opt Express
PUBLISHED: 09-01-2014
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Three-dimensional high-resolution imaging methods are important for cellular-level research. Optical coherence microscopy (OCM) is a low-coherence-based interferometry technology for cellular imaging with both high axial and lateral resolution. Using a high-numerical-aperture objective, OCM normally has a shallow depth of field and requires scanning the focus through the entire region of interest to perform volumetric imaging. With a higher-numerical-aperture objective, the image quality of OCM is affected by and more sensitive to aberrations. Interferometric synthetic aperture microscopy (ISAM) and computational adaptive optics (CAO) are computed imaging techniques that overcome the depth-of-field limitation and the effect of optical aberrations in optical coherence tomography (OCT), respectively. In this work we combine OCM with ISAM and CAO to achieve high-speed volumetric cellular imaging. Experimental imaging results of ex vivo human breast tissue, ex vivo mouse brain tissue, in vitro fibroblast cells in 3D scaffolds, and in vivo human skin demonstrate the significant potential of this technique for high-speed volumetric cellular imaging.
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ZmGns, a maize class I ?-1,3-glucanase, is induced by biotic stresses and possesses strong antimicrobial activity.
J Integr Plant Biol
PUBLISHED: 08-31-2014
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Plant ?-1,3-glucanases are members of the pathogenesis-related protein 2 (PR-2) family, which is one of the 17 PR protein families and plays important roles in biotic and abiotic stress responses. One of the differentially expressed proteins (spot 842) identified in a recent proteomic comparison between five pairs of closely related maize (Zea mays L.) lines differing in aflatoxin resistance was further investigated in the present study. Here, the corresponding cDNA was cloned from maize and designated as ZmGns. ZmGns encodes a protein of 338 amino acids containing a potential signal peptide. The expression of ZmGns was detectible in all tissues studied with the highest level in silks. ZmGns was significantly induced by biotic stresses including three bacteria and the fungus Aspergillus flavus. ZmGns was also induced by most abiotic stresses tested and growth hormones including salicylic acid. In vivo, ZmGns showed a significant inhibitory activity against the bacterial pathogen Pseudomonas syringae pv. tomato DC3000 and fungal pathogen Botrytis cinerea when it overexpressed in Arabidopsis. Its high level of expression in the silk tissue and its induced expression by phytohormone treatment, as well as by bacterial and fungal infections, suggest it plays a complex role in maize growth, development, and defense.
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Optical vortex beam based optical fan for high-precision optical measurements and optical switching.
Opt Lett
PUBLISHED: 08-29-2014
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The polarization and orbital angular momentum properties of light are of great importance in optical science and technology in the fields of high-precision optical measurements and high-capacity and high-speed optical communications. Here we show a method for the construction of a simple and robust scheme to rotate a light beam such as a fan, which is based on a combination of these two properties and using the thermal-dispersion and electro-optical effect of birefringent crystals. Using a computer-based digital image-processing technique, we determine the temperature and thermal-dispersion difference of the crystal with high resolution. We also use the rotation phenomenon to realize thermo-optic and electro-optic switches. The basic operating principles for measurement and switching processes are presented in detail. The methods developed here will have wide practical applicability in various fields, including remote sensing, materials science, and optical communication networks.
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Association of SCN1A, SCN2A and ABCC2 gene polymorphisms with the response to antiepileptic drugs in Chinese Han patients with epilepsy.
Pharmacogenomics
PUBLISHED: 08-27-2014
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The purpose of this study was to investigate the potential impact of SCN1A, SCN2A and ABCC2 gene polymorphisms on the response to antiepileptic drugs in Chinese Han patients with epilepsy.
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Efficient Coupling of Solar Energy to Catalytic Hydrogenation by Using Well-Designed Palladium Nanostructures.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 07-31-2014
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A Ru(3+) -mediated synthesis for the unique Pd concave nanostructures, which can directly harvest UV-to-visible light for styrene hydrogenation, is described. The catalytic efficiency under 100 mW?cm(-2) full-spectrum irradiation at room temperature turns out to be comparable to that of thermally (70?°C) driven reactions. The yields obtained with other Pd nanocrystals, such as nanocubes and octahedrons, are lower. The nanostructures reported here have sufficient plasmonic cross-sections for light harvesting in a broad spectral range owing to the reduced shape symmetry, which increases the solution temperature for the reaction by the photothermal effect. They possess a large quantity of atoms at corners and edges where local heat is more efficiently generated, thus providing active sites for the reaction. Taken together, these factors drastically enhance the hydrogenation reaction by light illumination.
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Glucose alleviates Cd toxicity by increasing Cd fixation in root cell wall and sequestration into vacuole in Arabidopsis.
J Integr Plant Biol
PUBLISHED: 07-30-2014
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Glucose is involved in not only plant physiological and developmental events but also plant responses to abiotic stresses. Here we found that the exogenous glucose improved root and shoot growth, reduced shoot cadmium (Cd) concentration, and rescued Cd-induced chlorosis in Arabidopsis thaliana under Cd stressed conditions. Glucose increased Cd retained in the roots, thus reduced its translocation from root to shoot significantly. The most Cd retained in the roots was found in the hemicellulose 1. Glucose combined with Cd (Glu?+?Cd) treatment did not affect the content of pectin and its binding capacity of Cd while it increased the content of hemicelluloses 1 and the amount of Cd retained in it significantly. Furthermore, Leadmium(TM) Green staining indicated that more Cd was compartmented into vacuoles in Glu?+?Cd treatment compared with Cd treatment alone, which was in accordance with the significant upregulation of the expression of tonoplast-localized metal transporter genes, suggesting that compartmentation of Cd into vacuoles also contributes to the glucose-alleviated Cd toxicity. Taken together, we demonstrated that glucose-alleviated Cd toxicity is mediated through increasing Cd fixation in the root cell wall and sequestration into the vacuoles.
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MicroRNA-100 promotes the autophagy of hepatocellular carcinoma cells by inhibiting the expression of mTOR and IGF-1R.
Oncotarget
PUBLISHED: 07-16-2014
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We found that restoration of miR-100 expression resulted in accumulation of LC3B-II and decrease of p62 in hepatocellular carcinoma (HCC) cells, whereas antagonism of miR-100 reduced the level of LC3B-II. Moreover, a significant correlation between miR-100 downregulation and p62 upregulation was observed in human HCC tissues, suggesting an autophagy-promoting effect of miR-100. Subsequent investigations disclosed that knockdown of Atg7 but not Beclin-1 attenuated the miR-100-induced LC3B-II elevation. Furthermore, miR-100 overexpression caused massive cell death, which was abrogated by both the Atg7 silencing and chloroquine treatment. Simultaneously, miR-100 expression led to increased fraction of cells with Annexin V-staining and loss of mitochondrial potential, implying that miR-100 may promote the Atg7-dependent autophagy and subsequent apoptotic cell death. Consistently, mouse xenograft models revealed that miR-100 inhibited the in vivo growth of HCC cells. We further showed that miR-100 suppressed the expression of mTOR and IGF-1R by binding to their 3' untranslated region, and knockdown of mTOR or IGF-1R phenocopied the pro-autophagy effect of miR-100, indicating that miR-100 may promote autophagy by reducing mTOR and IGF-1R level. Collectively, our data uncover a new regulatory mechanism of autophagy and a novel function of miR-100, and provide a potential therapeutic target for HCC.
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Preoperative evaluation of the neurovascular compression using magnetic resonance tomographic angiography: our radiologic indications for microvascular decompression to treat trigeminal neuralgia.
J Craniofac Surg
PUBLISHED: 07-10-2014
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The aim of this study was to introduce our classification of the neurovascular compression (NVC) in trigeminal neuralgia and the radiologic indications for microvascular decompression (MVD) based on magnetic resonance tomographic angiography.
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Broadband focusing and demultiplexing of surface plasmon polaritons on metal surface by holographic groove patterns.
Opt Express
PUBLISHED: 07-01-2014
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Manipulation of surface plasmon polaritons (SPPs) on metal surfaces is important for constructing ultracompact integrated micro/nano optical devices and systems. We employ the method of surface electromagnetic wave holography (SWH) to design holographic groove patterns for managing the transport of broadband SPPs on metal surface. Several sets of groove patterns corresponding to different wavelengths are etched on the same region on metal surface to form a broadband SPP hologram. The incident SPPs are scattered by the composite hologram and interfere with each other to focus at different or the same positions for SPPs of different wavelengths. Finite-difference time-domain simulations show that broadband demultiplexing of SPPs is realized by the designed plasmonic holographic structures. In addition, the broadband SPPs can be focused to a pre-designated spot by a designed plasmonic hologram and as a result focusing of an ultrashort plasmonic pulse can be achieved. The results show that the SWH can successfully handle design of plasmonic holographic structures for SPPs wavelength management on metal surface.
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Decreased expression of glutathione S-transferase pi correlates with poorly differentiated grade in patients with oral squamous cell carcinoma.
J. Oral Pathol. Med.
PUBLISHED: 06-13-2014
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Glutathione S transferase pi (GSTP1) is a member of phase II detoxification enzymes as a major regulator of cell signaling in response to stress, hypoxia, growth factors, and other stimuli. The clinical role of GSTP1 in cancer is still unclear. The aim of this study was to investigate the serum GSTP1 level in patients with oral squamous cell carcinoma (OSCC) and the GSTP1 expression in tissue samples from patients with OSCC and OSCC lines.
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Cellular expression profile of RhoA in rats with spinal cord injury.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 05-28-2014
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RhoA, a small GTPase, is involved in a wide array of cellular functions in the central nervous system, such as cell motility, cytoskeleton rearrangement, transcriptional regulation, phagocytosis and cell growth. It is not known how spinal cord injury (SCI) affects the expression of RhoA in different nerve cells. In the present study, we investigated the changes of RhoA expression in remote areas of the injury at the 3rd, 7th and 30th day after SCI, which was established by T10 contusion method. Moreover, we examine its expression profile in neurons, astrocytes and microglia. RhoA was found to be weakly expressed in these nerve cells in normal spinal cord. Western blotting showed that, after SCI, the total RhoA expression was up-regulated, and the RhoA expression was increased and peaked at the 7th day. Double immunostaining revealed specific and temporal expression patterns of RhoA in different nerve cells. The expression of RhoA in neurons started to increase at day 3, peaked at day 7 and then decreased slightly at day 30. Expression of RhoA in astrocytes increased moderately after SCI and peaked at day 7. There was no obvious change in RhoA expression in microglia after SCI in remote areas. This study demonstrated that, after SCI, RhoA expression exhibited different patterns with different nerve cells of spinal cord. RhoA expression patterns also changed with time after SCI, and among different nerve cells in the injured spinal cord. These findings can help us better understand the roles of RhoA in SCI.
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A Prospective Study of Medial Sural Artery Perforator Flap with Computed Tomographic Angiography-Aided Design in Tongue Reconstruction.
J. Oral Maxillofac. Surg.
PUBLISHED: 05-28-2014
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To investigate the application of the medial sural artery perforator flap in hemiglossectomy reconstruction and evaluate the value of preoperative computed tomographic angiography (CTA) for perforator location.
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Generation of light with controllable spatial patterns via the sum frequency in quasi-phase matching crystals.
Sci Rep
PUBLISHED: 05-27-2014
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Light beams with extraordinary spatial structures, such as the Airy beam (AB), the Bessel-Gaussian beam (BGB) and the Laguerre-Gaussian beam (LGB), are widely studied and applied in many optical scenarios. We report on preparation of light beams with controllable spatial structures through sum frequency generation (SFG) using two Gaussian pump beams in a quasi-phase matching (QPM) crystal. The spatial structures, including multi-ring-like BGB, donut-like LGB, and super-Gaussian-like beams, can be controlled periodically via crystal phase mismatching by tuning the pump frequency or crystal temperature. This phenomenon has not been reported or discussed previously. Additionally, we present numerical simulations of the phenomenon, which agree very well with the experimental observations. Our findings give further insight into the SFG process in QPM crystals, provide a new way to generate light with unusual spatial structures, and may find applications in the fields of laser optics, all-optical switching, and optical manipulation and trapping.
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Epigenetic modifier-induced biosynthesis of novel acetylenic sterols from Cladosporium colocasiae.
Steroids
PUBLISHED: 05-19-2014
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The addition of an HDAC inhibitor, suberoylanilide hydroxamic acid (SBHA), to the culture medium of Cladosporium colocasiae, dramatically altered its metabolic profiles. Analysis of the culture broth extract led to the isolation of two new acetylenic sterols (1-2). The isolated compounds were further evaluated for their cytotoxic and antibacterial activities. Compound 1 showed activity against Bacillus subtilis, affording a zone of inhibition of 12mm at 100?g/disk. However, none of them showed noticeable growth inhibitory effects.
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Hydrogen sulfide inhibits opioid withdrawal-induced pain sensitization in rats by down-regulation of spinal calcitonin gene-related peptide expression in the spine.
Int. J. Neuropsychopharmacol.
PUBLISHED: 05-13-2014
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Hyperalgesia often occurs in opioid-induced withdrawal syndrome. In the present study, we found that three hourly injections of DAMGO (a ?-opioid receptor agonist) followed by naloxone administration at the fourth hour significantly decreased rat paw nociceptive threshold, indicating the induction of withdrawal hyperalgesia. Application of NaHS (a hydrogen sulfide donor) together with each injection of DAMGO attenuated naloxone-precipitated withdrawal hyperalgesia. RT-PCR and Western blot analysis showed that NaHS significantly reversed the gene and protein expression of up-regulated spinal calcitonin gene-related peptide (CGRP) in naloxone-treated animals. NaHS also inhibited naloxone-induced cAMP rebound and cAMP response element-binding protein (CREB) phosphorylation in rat spinal cord. In SH-SY5Y neuronal cells, NaHS inhibited forskolin-stimulated cAMP production and adenylate cyclase (AC) activity. Moreover, NaHS pre-treatment suppressed naloxone-stimulated activation of protein kinase C (PKC) ?, Raf-1, and extracellular signal-regulated kinase (ERK) 1/2 in rat spinal cord. Our data suggest that H2S prevents the development of opioid withdrawal-induced hyperalgesia via suppression of synthesis of CGRP in spine through inhibition of AC/cAMP and PKC/Raf-1/ERK pathways.
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Seed-mediated synthesis of gold tetrahedra in high purity and with tunable, well-controlled sizes.
Chem Asian J
PUBLISHED: 05-08-2014
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We report a facile synthesis of Au tetrahedra in high purity and with tunable, well-controlled sizes via seed-mediated growth. The success of this synthesis relies on the use of single-crystal, spherical Au nanocrystals as the seeds and manipulation of the reaction kinetics to induce an unsymmetrical growth pattern for the seeds. In particular, the dropwise addition of a precursor solution with a syringe pump, assisted by cetyltrimethylammonium chloride and bromide at appropriate concentrations, was found to be critical to the formation of Au tetrahedra in high purity. Their sizes could be readily tuned in the range of 30-60?nm by simply varying the amount of precursor added to the reaction solution. The current strategy not only enables the synthesis of Au tetrahedra with tunable and controlled sizes but also provides a facile and versatile approach to reducing the symmetry of nanocrystals made of a face-centered cubic lattice.
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The genus Codonopsis (Campanulaceae): a review of phytochemistry, bioactivity and quality control.
J Nat Med
PUBLISHED: 05-07-2014
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Codonopsis, in the family Campanulaceae, is a genus containing 42 species of dicotyledonous herbaceous perennial plants, predominantly found in Central, East and South Asia. Several Codonopsis species are widely used in traditional medicine and are considered to have multiple medicinal properties. Among the Codonopsis species, Codonopsis pilosula (Franch.) Nannf. and C. lanceolata (Sieb. et Zucc.) Benth. & Hook. f. ex Trautv. are more popular than others according to the findings, especially phytochemical and bioactive studies. Phytochemical research shows that Codonopsis species contain mainly polyacetylenes, phenylpropanoids, alkaloids, triterpenoids and polysaccharides, which contribute to multiple bioactivities. However, the mechanisms of their bioactivities need to be further elucidated. The less popular Codonopsis species remain to be studied and exploited. In addition, although a series of methods for the quality evaluation of Codonopsis species have been developed, a feasible and reliable approach to the efficacious and safe use of various Codonopsis species is still needed, with considering botanical origin, chemical constituents and bioactive effects. This review aims to provide up-to-date and comprehensive information on the phytochemistry, bioactivity and quality control of medicinal plants in the genus Codonopsis and to highlight current gaps in knowledge, which is useful for the wider development of the Codonopsis genus.
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Sulfhydration of p66Shc at Cysteine59 Mediates the Antioxidant Effect of Hydrogen Sulfide.
Antioxid. Redox Signal.
PUBLISHED: 04-29-2014
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Abstract Aims: Mitochondrion is considered as the major source of intracellular reactive oxygen species (ROS). H2S has been reported to be an antioxidant, but its mechanism remains largely elusive. P66Shc is an upstream activator of mitochondrial redox signaling. The aim of this study was to explore whether the antioxidant effect of H2S is mediated by p66Shc. Results: Application of exogenous H2S with its donor, NaHS, or overexpression of its generating enzyme, cystathionine ?-synthase, induced sulfhydration of p66Shc, but inhibited its phosphorylation caused by H2O2/D-galactose in SH-SY5Y cells or in the mice cortex. H2S also decreased mitochondrial ROS production and protected neuronal cells against stress-induced senescence. PKC?II and PP2A are the two key proteins to regulate p66Shc phosphorylation. Although H2S failed to affect the activities of these two proteins, it disrupted their association. Cysteine-59 resides in proximity to serine-36, the phosphorylation site of p66Shc. The C59S mutant attenuated the above-described biological function of H2S. Innovation: We revealed a novel mechanism for the antioxidant effect of H2S and its role in oxidative stress-related diseases. Conclusion: H2S inhibits mitochondrial ROS production via the sulfhydration of Cys-59 residue, which in turn, prevents the phosphorylation of p66Shc. Antioxid. Redox Signal. 00, 000-000.
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Differentiation of Crohn's disease from intestinal tuberculosis by clinical and CT enterographic models.
Inflamm. Bowel Dis.
PUBLISHED: 04-04-2014
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Crohn's disease (CD) and intestinal tuberculosis (ITB) have similar clinical, radiological, and endoscopic features. The objective of our study was to investigate the values of clinical features and computed tomographic (CT) enterographic manifestations in the differential diagnosis between CD and ITB.
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Demonstration of broad photonic crystal stop band in a freely-suspended microfiber perforated by an array of rectangular holes.
Opt Express
PUBLISHED: 03-26-2014
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It is shown that photonic crystal (PhC) optical reflectors with reflectance in excess of 60% and fractional bandwidths greater than 10% can be fabricated by ion beam milling of fewer than ten periods of rectangular cross section through-holes in micron-scale tapered fibers. The optical characteristics agree well with numerical simulations when allowance is made for fabrication artefacts and we show that the radiation loss, which is partly determined by optical interference, can be suppressed by design. The freely-suspended devices are compact and robust and could form the basic building block of optical cavities and filters.
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Comparison of stroke volume variation with pulse pressure variation as a diagnostic indicator of fluid responsiveness in mechanically ventilated critically ill patients.
Saudi Med J
PUBLISHED: 03-14-2014
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To compare the diagnostic accuracy of stroke volume variation (SVV) and pulse pressure variation (PPV) in studies that examined both parameters in the same patient population.
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Ozone oxidative preconditioning inhibits renal fibrosis induced by ischemia and reperfusion injury in rats.
Exp Ther Med
PUBLISHED: 03-06-2014
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Ischemia and reperfusion injury (IRI) is a crucial contributor to the development of renal fibrosis. Ozone has been proposed as a novel medical therapy for various conditions, including organ IRI. The aim of this study was to investigate whether ozone oxidative preconditioning (OzoneOP) has a beneficial effect in preventing the development of renal fibrosis following IRI. Sprague Dawley rats were subjected to 45 min of ischemia followed by 8 weeks of reperfusion. Prior to surgery, rats in the OzoneOP group were treated with ozone and those in the IRI and Sham groups were untreated. Blood samples were collected for the detection of blood urea nitrogen (BUN) and creatinine (Cr) levels. To assess tissue fibrosis, Masson's trichrome staining was performed. Immunohistochemistry was also performed to determine the localization of ?-smooth muscle actin (?-SMA). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting were conducted to analyze the expression of transforming growth factor (TGF)-?1, ?-SMA and Smad7. The levels of BUN and Cr did not significantly differ between groups. Rats pretreated with ozone showed markedly less interstitial fibrosis than untreated rats following IRI. In addition, immunohistochemistry revealed that ?-SMA expression was attenuated in the OzoneOP group compared with the IRI group. RT-qPCR and western blot analysis showed that OzoneOP inhibited the IRI-induced increases in ?-SMA and TGF-?1 expression levels, and that the IRI-induced reduction in the expression of Smad7 was inhibited in the OzoneOP group. The results indicate that OzoneOP has beneficial effects on ischemic renal fibrosis. OzoneOP may exert its protective effects by a mechanism involving modulation of the TGF-?1/Smad7 pathway.
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Is omega-3 fatty acids enriched nutrition support safe for critical ill patients? A systematic review and meta-analysis.
Nutrients
PUBLISHED: 03-05-2014
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To systematically review the effects of omega-3 poly unsaturated fatty acids (FA) enriched nutrition support on the mortality of critically illness patients.
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Direct method to control surface plasmon polaritons on metal surfaces.
Opt Lett
PUBLISHED: 02-25-2014
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The manipulation of surface plasmon polaritons (SPPs) on metal surfaces is an important aspect in the design of ultra-compact integrated micro/nano optical systems. We present a direct method for the easy, yet accurate design of complicated groove patterns to control SPPs traveling on metal surfaces, using a surface electromagnetic wave holography method, based on the Huygens-Fresnel principle. SPPs are scattered by these deliberately and appropriately determined groove patterns and interfere with each other to form new paths with desire. Two devices are demonstrated, with predesignated functionalities fully implemented by the designed plasmonic holographic structures, according to the finite-difference time-domain simulations. The results strongly indicate that this direct method is effective, efficient, and user friendly in its application to control SPPs on metal surfaces.
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Image cloning beyond diffraction based on coherent population trapping in a hot rubidium vapor.
Opt Lett
PUBLISHED: 02-25-2014
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Following recent theoretical predictions, we report on an experimental realization of image cloning beyond usual diffraction, through the coherent population trapping (CPT) effect in a hot rubidium vapor. In our experiment, an alphabet letter image was transferred from a coupling field to a probe field, based on the CPT effect. Furthermore, we demonstrate that the cloned probe field carrying the image is transmitted without the usual diffraction. To our best knowledge, this is the first experimental report about image cloning beyond diffraction. We believe this mechanism, based on CPT, has definite and important applications in image metrology, image processing, and biomedical imaging.
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Effectiveness of 10-year vaccination (2001-2010) on Hepatitis A in Tianjin, China.
Hum Vaccin Immunother
PUBLISHED: 02-08-2014
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Vaccination is an effective strategy to prevent and control the transmission of hepatitis A. Hepatitis A immunization program has been taken into effect since 2001 in Tianjin, China. This study evaluated the effectiveness of strategies in the prevention and control of hepatitis A. Data of serological survey, annual hepatitis A incidence, immunization coverage and the positive rate of hepatitis A IgG before and after the immunization program in residents under 15 years old were used to do the analysis. The results indicated that hepatitis A vaccine induced a striking decrease of hepatitis A incidence and a significant increase in the positive rate of anti-HAV IgG among the children younger than 15 years old. Hepatitis A vaccination in children was proved to be effective in the prevention and control of hepatitis A in Tianjin, China.
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Primary intraosseous adenoid cystic carcinoma of the jaw: clinical and histopathologic analysis.
J. Oral Maxillofac. Surg.
PUBLISHED: 02-01-2014
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Adenoid cystic carcinoma (ACC), formerly known as cylindroma, is a malignant epithelial neoplasm typically derived from the salivary glands. Of all salivary gland tumors, the incidence of malignant salivary gland tumor has been 15 to 32% in the parotid glands, 70 to 90% in the sublingual glands, and about 50% in the minor salivary glands. Intraosseous ACC of the jaw has rarely been reported and is poorly understood. The aim of the present study was to analyze this tumor clinically and histopathologically to improve the diagnosis, management, and treatment.
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Optimization of the antiviral potency and lipophilicity of halogenated 2,6-diarylpyridinamines as a novel class of HIV-1 NNRTIS.
ChemMedChem
PUBLISHED: 01-30-2014
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Nineteen new halogenated diarylpyridinamine (DAPA) analogues modified at the phenoxy C-ring were synthesized and evaluated for anti-HIV activity and certain drug-like properties. Ten compounds showed high anti-HIV activity (EC50 <10?nM). In particular, (E)-6-(2''-bromo-4''-cyanovinyl-6''-methoxy)phenoxy-N(2) -(4'-cyanophenyl)pyridin-2,3-diamine (8?c) displayed low-nanomolar antiviral potency (3-7?nM) against wild-type and drug-resistant viral strains bearing the E138K or K101E mutations, which are associated with resistance to rilvipirine (1?b). Compound 8?c exhibited much lower resistance fold changes (RFC: 1.1-2.1) than 1?b (RFC: 11.8-13.0). Compound 8?c also exhibited better metabolic stability (in vitro half-life) than 1?b in human liver microsomes, possessed low lipophilicity (clog?D: 3.29; measured log?P: 3.31), and had desirable lipophilic efficiency indices (LE>0.3, LLE>5, LELP<10). With balanced potency and drug-like properties, 8?c merits further development as an anti-HIV drug candidate.
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A prognostic classifier consisting of 17 circulating cytokines is a novel predictor of overall survival for metastatic colorectal cancer patients.
Int. J. Cancer
PUBLISHED: 01-20-2014
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We aimed to determine the prognostic values of 39 circulating cytokines in Chinese patients with metastatic colorectal cancer (CRC) and to develop a novel cytokine-based prognostic classifier (CBPC) for prognostic prediction. A total of 176 patients were divided into two cohorts based on the date of first-line chemotherapy. The first 99 cases were assigned to the training cohort, and the remaining 77 cases were assigned to the validation cohort. Thirty-nine cytokines were simultaneously analyzed in the patient serum samples using multiplex bead-based Luminex technology. We used support vector machine-based methods and Cox proportional hazards models to develop a CBPC from the training cohort, which we then validated using the second patient cohort. Univariate analysis showed that FGF-2, TGF?, Flt-3L, GM-CSF, INF?2, GRO, IL-10, MCP-3, MDC, sIL-2R?, IL-2, IL-7, IL-8, MCP-1, MIP-1?, TNF? and VEGF were significant risk factors affecting the overall survival (OS) of both the training cohort and the validation cohort. We developed a CBPC to predict the OS of metastatic CRC patients using these 17 cytokines (sensitivity, 0.835; specificity, 0.800). In the validation cohort, the CBPC was found to have significant power in predicting the OS of metastatic CRC patients. Our study showed that there were significant associations between cytokine expression and prognosis of the patients with metastatic CRC. The CBPC that we developed includes multiple circulating cytokines and may serve as a novel screening tool for identifying metastatic CRC patients with a high risk of short OS. These high-risk individuals may also be suitable for cytokine-targeted therapies.
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Different responses of cell cycle between rat vascular smooth muscle cells and vascular endothelial cells to paclitaxel.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 01-17-2014
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Although previous reports showed drug-eluting stent (DES) could effectively inhibit neointima formation, in-stent restenosis (ISR) remains an important obstacle. The purpose of this study was to investigate different effects of paclitaxel on proliferation and cell cycle regulators between vascular smooth muscle cells (VSMCs) and vascular endothelial cells (VECs) of rats in vitro. The cultured VSMCs and VECs of rats from the same tissues were examined by using immunohistochemistry, flow cytometry and Western blotting in control and paclitaxel-treated groups. The results showed paclitaxel could effectively inhibit proliferation of VSMCs and VECs. However, as compared with VECs, proliferation of VSMCs in paclitaxel-treated group decreased less rapidly. The percentage of cells in G0-G1 and G2-M phases was reduced, and that in S phase increased after treatment for 72 h. The expression of cyclin D1 and B1, p27 and PCNA in VSMCs of paclitaxel-treated group was up-regulated, but that of p21 down-regulated as compared with VECs. It is concluded that there are significant differences in the expression of cell cycle regulators and proliferation rate between paclitaxel-treated VSMCs and paclitaxel-treated VECs, suggesting that the G1-S checkpoint regulated by paclitaxel may play a critical role in the development of complications of DES, which provides new strategies for treatments of ISR.
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Palladium/norbornene-mediated tandem C-H amination/C-I alkenylation reaction of aryl iodides with secondary cyclic O-benzoyl hydroxylamines and activated terminal olefins.
Chemistry
PUBLISHED: 01-08-2014
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A novel palladium-catalyzed norbornene-mediated three-component reaction for the construction of ortho-alkenyl aromatic tertiary amines has been achieved, which represents a useful extension of the Catellani-type tandem ortho-selective C?H amination transformations.
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DNA Damage Enhanced by the Attenuation of SLD5 Delays Cell Cycle Restoration in Normal Cells but Not in Cancer Cells.
PLoS ONE
PUBLISHED: 01-01-2014
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SLD5 is a member of the GINS complex composed of PSF1, PSF2, PSF3 and SLD5, playing a critical role in the formation of the DNA replication fork with CDC45 in yeast. Previously, we had isolated a PSF1 orthologue from a murine hematopoietic stem cell DNA library and were then able to identify orthologues of all the other GINS members by the yeast two hybrid approach using PSF1 as the bait. These GINS orthologues may also function in DNA replication in mammalian cells because they form tetrameric complexes as observed in yeast, and gene deletion mutants of both PSF1 and SLD5 result in a lack of epiblast proliferation and early embryonic lethality. However, we found that PSF1 is also involved in chromosomal segregation in M phase, consistent with recent suggestions that homologues of genes associated with DNA replication in lower organisms also regulate cellular events other than DNA replication in mammalian cells. Here we analyzed the function of SLD5 other than DNA replication and found that it is active in DNA damage and repair. Attenuation of SLD5 expression results in marked DNA damage in both normal cells and cancer cells, suggesting that it protects against DNA damage. Attenuation of SLD5 delays the DNA repair response and cell cycle restoration in normal cells but not in cancer cells. These findings suggest that SLD5 might represent a therapeutic target molecule acting at the level of tumor stromal cells rather than the cancerous cells themselves, because development of the tumor microenvironment could be delayed or disrupted by the suppression of its expression in the normal cell types within the tumor.
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Hepatic resection is safe and effective for patients with hepatocellular carcinoma and portal hypertension.
PLoS ONE
PUBLISHED: 01-01-2014
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Official guidelines do not recommend hepatic resection (HR) for patients with hepatocellular carcinoma (HCC) and portal hypertension (PHT). This study aims to investigate the safety and efficacy of HR for patients with HCC and PHT.
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Icariin ameliorates neuropathological changes, TGF-?1 accumulation and behavioral deficits in a mouse model of cerebral amyloidosis.
PLoS ONE
PUBLISHED: 01-01-2014
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Icariin, a major constituent of flavonoids from the Chinese medicinal herb Epimedium brevicornum, exhibits multiple biological properties, including anti-inflammatory, neuroregulatory and neuroprotective activities. Therefore, Icariin might be applied in treatment of neurodegenerative disorders, including Alzheimer's disease (AD), which is neuropathologically characterized by ?-amyloid aggregation, hyperphosphorylated tau and neuroinflammation. Potential therapeutic effects of Icariin were investigated in an animal model of cerebral amyloidosis for AD, transgenic APP/PS1 mouse. Icariin was suspended in carboxymethylcellulose and given orally to APP/PS1 mice. Therapeutic effects were monitored by behavioral tests, namely nesting assay, before and during the experimental treatment. Following an oral treatment of 10 days, Icariin significantly attenuated A? deposition, microglial activation and TGF-?1 immunoreactivity at amyloid plaques in cortex and hippocampus of transgenic mice 5 months of age, and restored impaired nesting ability. Our results suggest that Icariin might be considered a promising therapeutic option for human AD.
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Environmental influences on maize-Aspergillus flavus interactions and aflatoxin production.
Front Microbiol
PUBLISHED: 01-01-2014
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Since the early 1960s, the fungal pathogen Aspergillus flavus (Link ex Fr.) has been the focus of intensive research due to the production of carcinogenic and highly toxic secondary metabolites collectively known as aflatoxins following pre-harvest colonization of crops. Given this recurrent problem and the occurrence of a severe aflatoxin outbreak in maize (Zea mays L.), particularly in the Southeast U.S. in the 1977 growing season, a significant research effort has been put forth to determine the nature of the interaction occurring between aflatoxin production, A. flavus, environment and its various hosts before harvest. Many studies have investigated this interaction at the genetic, transcript, and protein levels, and in terms of fungal biology at either pre- or post-harvest time points. Later experiments have indicated that the interaction and overall resistance phenotype of the host is a quantitative trait with a relatively low heritability. In addition, a high degree of environmental interaction has been noted, particularly with sources of abiotic stress for either the host or the fungus such as drought or heat stresses. Here, we review the history of research into this complex interaction and propose future directions for elucidating the relationship between resistance and susceptibility to A. flavus colonization, abiotic stress, and its relationship to oxidative stress in which aflatoxin production may function as a form of antioxidant protection to the producing fungus.
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[Effect of Midazolam on Mantle Cell Lymphoma JeKo-1 Cell Line and Its Relevant Mechanisms].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 12-28-2013
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This study was aimed to explore the effect of midazolam on mantle cell lymphoma cell line JeKo-1 and the relevant mechanisms. Effects of midazolam on the proliferation and apoptosis of JeKo-1 cells were observed by CCK8 assay and flow cytometry, respectively. Effect of midazolam on the expression of BCL-2, cytochrome C(Cyto-C), pro-caspase-9, pro-caspase-8 and pro-caspase-3 protein were detected by Western blot. The results showed that midazolam could inhibit the growth of JeKo-1 cells significantly and the concentration of 50% growth inhibition (IC50) at 48 hours was approximately 40 µmol/L. After treatment with 20, 40, 80 µmol/L midazolam for 48 hours, a dose-dependent apoptosis of JeKo-1 cells could be observed. Meanwhile, a dose-dependent reduction of BCL-2, pro-caspase-9 and pro-caspase-3 protein expression and increase of Cyto-C protein expression in JeKo-1 cells were found, but the expression of pro-caspase-8 protein did not change. It is concluded that midazolam possibly initiates the mitochondrial pathway, not the death receptor pathway, by reducing the expression of BCL-2, leading in turn to the releasing of Cyto-C in mitochondria, then activating caspase-9 and caspase-3 protein, triggers the caspase cascade, and induces the apoptosis of JeKo-1 cells ultimately.
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[Nitrite denitrification characteristics with redox mediator].
Huan Jing Ke Xue
PUBLISHED: 12-03-2013
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This study optimized the nitrite degradation conditions and explored the characteristics of nitrite degradation with redox mediators and nitrite denitrifying bacteria. The results suggested that the optimal condition of nitrite denitrification was 35 degrees C, pH = 8.0, sodium succinate as the carbon source, the C/N rate of 4 and the initial nitrite concentration of 100 mg x L(-1); the optimal AQS concentration was 0. 16 mmol x L(-1); ORP values stabilized around -400 mV to -500 mV with AQS, which were lower than that of controls during the denitrification process; the pH changed with nitrite removal and stabilized at 9 to 10; through the analysis of denitrifying intermediate metabolites, the impact of AQS on nitrite denitrifying process presumably not only played a coenzyme CoQ role but also accelerated the cytochrome transfer electronic process. This study provides the optimal parameters for practical application of the nitrite biodegradation with redox mediator.
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Dramatic suppression of colorectal cancer cell growth by the dual mTORC1 and mTORC2 inhibitor AZD-2014.
Biochem. Biophys. Res. Commun.
PUBLISHED: 11-18-2013
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Colorectal cancer is a major contributor of cancer-related mortality. The mammalian target or rapamycin (mTOR) signaling is frequently hyper-activated in colorectal cancers, promoting cancer progression and chemo-resistance. In the current study, we investigated the anti-colorectal cancer effect of a novel mTOR complex 1 (mTORC1) and mTORC2 dual inhibitor: AZD-2014. In cultured colorectal cancer cell lines, AZD-2014 significantly inhibited cancer cell growth without inducing significant cell apoptosis. AZD-2014 blocked activation of both mTORC1 (S6K and S6 phosphorylation) and mTORC2 (Akt Ser 473 phosphorylation), and activated autophagy in colorectal cancer cells. Meanwhile, autophagy inhibition by 3-methyaldenine (3-MA) and hydroxychloroquine, as well as by siRNA knocking down of Beclin-1 or ATG-7, inhibited AZD-2014-induced cytotoxicity, while the apoptosis inhibitor had no rescue effect. In vivo, AZD-2014 oral administration significantly inhibited the growth of HT-29 cell xenograft in SCID mice, and the mice survival was dramatically improved. At the same time, in xenografted tumors administrated with AZD-2014, the activation of mTORC1 and mTORC2 were largely inhibited, and autophagic markers were significantly increased. Thus, AZD-2014 inhibits colorectal cancer cell growth both in vivo and in vitro. Our results suggest that AZD-2014 may be further investigated for colorectal cancer therapy in clinical trials.
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[Research advance in medicinal plants from genus Coreopsis].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-16-2013
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There are about 100 species in the genus Coreopsis which distributed in the America, south of Africa and Hawaiian Islands, and 7 species are distributed in China. The inflorescences of Coreopsis tinctoria Nutt. is the Uigur herb Snow chrysanthemum which is named Shemuju with the effects of heat-cleaning, detoxicating, dampness-dissipating and dysentery-curing in the Xinhua Herbal Scheme. The chemical constituents from Coreopsis plants mainly contain flavonoids, phenylpropanoids, sesquiterpenes, and sterols, which show anti-inflammatory activities in modern pharmaceutical research. This article presents an overview of the chemical constituents and pharmaceutical activities, prospects of development and exploitation of Coreopsis plants, hopefully to provide a basis for further research and development of Coreopsis plants.
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[Identification of differently expressed microRNas in keloid and pilot study on biological function of miR-199a-5p].
Zhonghua Zheng Xing Wai Ke Za Zhi
PUBLISHED: 11-16-2013
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To screen out related microRNAs in keloid tissue, and identify their effect on the proliferation of keloid fibroblasts.
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Risk factors for early and late intrahepatic recurrence in patients with single hepatocellular carcinoma without macrovascular invasion after curative resection.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-03-2013
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Prognostic factors of postoperative early and late recurrence in patients with hepatocellular carcinoma (HCC) undergoing curative resection remain to be clarified. The aim of this study was to identify risk factors for postoperative early (? 2 year) and late (> 2 year) intrahepatic recurrences in patients with single HCCs without macrovascular invasion.
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Physical and Functional Interaction of Rnf2 with Af9 Regulates Basal and Aldosterone-stimulated Transcription of the ?-ENaC Gene in a Renal Collecting Duct Cell Line.
Biosci. Rep.
PUBLISHED: 09-28-2013
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The physical and functional interaction of RING finger protein 2 (Rnf2), a central component of the Polycomb repressive complex (PRC) 1, and ALL1-fused gene from chromosome 9 protein (Af9), an aldosterone-sensitive transcription factor, in regulating basal and aldosterone-stimulated transcription of the ?-ENaC (epithelial Na+ channel ?-subunit) gene was explored in mIMCD3 collecting duct cells. Since Rnf2 lacks DNA-specific binding activity, other factors must mediate its site-specific chromatin recruitment. Rnf2 and Af9 co-localized in the nucleus and co-immunoprecipitated. A GST-Af9 carboxy-terminal fusion protein directly interacted with in vitro translated Rnf2 in GST pull-down assays. Rnf2 knockdown enhanced basal and aldosterone-stimulated ?-ENaC mRNA levels and ?-ENaC promoter activity. ChIP/qPCR assays demonstrated enrichment of Rnf2, mono-ubiquitinated histone H2A lysine 119 (H2AK119), and trimethylated histone H3 lysine 27 (H3K27), a PRC2 chromatin mark, at multiple ?-ENaC promoter subregions corresponding to regions of known Af9 enrichment, under basal conditions. Sequential ChIP confirmed Rnf2-Af9 co-occupancy of the ?-ENaC promoter. Aldosterone provoked early and sustained depletion of Rnf2, ubiquitinated H2AK119, and trimethylated H3K27 associated with the subregions of the ?-ENaC promoter. Thus, Af9 mediates site-selective physical and functional recruitment of Rnf2 to the ?-ENaC promoter to constrain basal ?-ENaC transcription in collecting duct cells, and aldosterone reverses this process.
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The Role of Etching in the Formation of Ag Nanoplates with Straight, Curved and Wavy Edges and Comparison of Their SERS Properties.
Small
PUBLISHED: 09-04-2013
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We investigate the role of etching in the formation of Ag nanoplates with different morphologies. By examining the reduction of AgNO3 with poly(vinyl pyrrolidone) in an aqueous solution under a hydrothermal condition, we confirm that etching plays an essential role in promoting the growth of Ag triangular nanoplates with straight edges at the expense of multiple twinned particles via Ostwald ripening. Once all the multiple twinned particles are gone, etching will continue at the corners of nanoplates, leading to the formation of enneahedral nanoplates with curved edges. When the nanoplates with straight edges are transferred into ethanol and subjected to a solvothermal treatment, we obtain nanoplates with wavy edges and sharp corners due to etching on the edges. A comparison study indicates that, at the same particle concentration, Ag nanoplates with wavy edges embraces a SERS enhancement factor at least 6 and 13 times stronger than those with straight and curved edges, respectively. The results from finite difference time domain calculations support our experimental observation that the sharp features on nanoplates with wavy edges are the most active sites for SERS.
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[Treatment of sixty-one patients with coronary slow flow phenomenon by yiqi huoxue recipe combined Western drugs: a clinical research].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 08-29-2013
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To observe the clinical efficacy of treating patients with coronary slow flow phenomenon by Yiqi Huoxue Recipe (YHR) combined Western drugs, thus providing clinical evidence for further studies.
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Phenanthrenes from Juncus effusus.
Planta Med.
PUBLISHED: 08-26-2013
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A chemical investigation of the EtOAc-soluble fraction from the ethanol extract of the medullae of Juncus effusus led to the isolation of three new 9,10-dihydrophenanthrenes, juncuenins E-G (1-3); two new phenanthrenes, dehydrojuncuenins D-E (4-5); one new feruloylated glycoside (6); and one known 9,10-dihydrophenanthrene (7). The structures of these compounds were determined by analyzing their spectroscopic data. Metabolites 1-4 and 7 were further evaluated for their in vitro cytotoxic activities against seven human cancer lines (A549, MCF-7, BEL-7402, HeLa, COLO205, BGC-823, and SK-OV-3). Among them, compound 1 exhibited weak cytotoxicity against MCF-7 and HeLa cell lines. Compound 7 showed moderate cytotoxicity against MCF-7 and HeLa cell lines, with IC50 values of 9.17 and 19.6 µM, respectively.
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Holographic plasmonic lenses for surface plasmons with complex wavefront profile.
Opt Express
PUBLISHED: 08-14-2013
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We present a direct-method solution toward the general problem of plasmonic wavefront manipulation and shaping to realize pre-designated functionalities based on the surface-wave holography (SWH) method. We demonstrate theoretically and experimentally the design and fabrication of holographic plasmonic lenses over surface plasmons with complex wavefront profiles. We show that visible light at 632.8 nm transmitting through a high-aspect-ratio slit or a micro-rectangle hole in a silver film can be focused to a preset three-dimensional point spot in free space via appropriately manipulating the interaction of excited surface plasmons with the nanoscale groove pattern of the holographic lens. The experiment results of scanning near-field optical microscopy for measuring the three-dimensional optical field distribution agree well both with designs and with numerical simulations, and this strongly supports the effectiveness and efficiency of the SWH method in the design of plasmonic devices that can fulfill manipulation and transformation of complicated-profile surface plasmons.
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Controllable synthesis of ZnO nanostructures on the Si substrate by a hydrothermal route.
Nanoscale Res Lett
PUBLISHED: 08-08-2013
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In this paper, controllable synthesis of various ZnO nanostructures was achieved via a simple and cost-effective hydrothermal process on the Si substrate. The morphology evolution of the ZnO nanostructures was well monitored by tuning hydrothermal growth parameters, such as the seed layer, solution concentration, reaction temperature, and surfactant. X-ray diffraction and photoluminescence measurements reveal that crystal quality and optical properties crucially depend on the morphology of the ZnO nanostructures. The ease of synthesis and convenience to tune morphology and optical properties bring this approach great potential for nanoscale applications.
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Breeding aflatoxin-resistant maize lines using recent advances in technologies - a review.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess
PUBLISHED: 07-16-2013
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Aflatoxin contamination caused by Aspergillus flavus infection of corn is a significant and chronic threat to corn being used as food or feed. Contamination of crops at levels of 20 ng g(-1) or higher (as regulated by the USFDA) by this toxin and potent carcinogen makes the crop unsalable, resulting in a significant economic burden on the producer. This review focuses on elimination of this contamination in corn which is a major US crop and the basis of many products. Corn is also "natures example" of a crop containing heritable resistance to aflatoxin contamination, thereby serving as a model for achieving resistance to aflatoxin contamination in other crops as well. This crop is the largest production grain crop worldwide, providing food for billions of people and livestock and critical feedstock for production of biofuels. In 2011, the economic value of the US corn crop was US$76 billion, with US growers producing an estimated 12 billion bushels, more than one-third of the worlds supply. Thus, the economics and significance of corn as a food crop and the threat to food safety due to aflatoxin contamination of this major food crop have prompted the many research efforts in many parts of the world to identify resistance in corn to aflatoxin contamination. Plant breeding and varietal selection has been used as a tool to develop varieties resistance to disease. This methodology has been employed in defining a few corn lines that show resistance to A. flavus invasion; however, no commercial lines have been marketed. With the new tools of proteomics and genomics, identification of resistance mechanisms, and rapid resistance marker selection methodologies, there is an increasing possibility of finding significant resistance in corn, and in understanding the mechanism of this resistance.
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Hydrogen Sulfide Attenuates Opioid Dependence by Suppression of Adenylate Cyclase/cAMP Pathway.
Antioxid. Redox Signal.
PUBLISHED: 07-11-2013
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Abstract Aims: The best-established mechanism of opioid dependence is the up-regulation of adenylate cyclase (AC)/cAMP pathway, which was reported to be negatively regulated by hydrogen sulfide (H2S), a novel endogenous neuromodulator. The present study was, therefore, designed to determine whether H2S is able to attenuate the development of opioid dependence via down-regulating AC/cAMP pathway. Results: We demonstrated that application of sodium hydrosulphide (NaHS) and GYY4137, two donors of H2S, significantly alleviated naloxone-induced robust withdrawal jumping (the most sensitive and reliable index of opioid physical dependence) in morphine-treated mice. Repeated treatment with NaHS inhibited the up-regulated protein expression of AC in the striatum of morphine-dependent mice. Furthermore, NaHS also attenuated morphine/naloxone-elevated mRNA levels of AC isoform 1 and 8, production of cAMP, and phosphorylation of cAMP response element-binding protein (CREB) in mice striatum. These effects were mimicked by the application of exogenous H2S or over-expression of cystathione-?-synthase, an H2S -producing enzyme, in SH-SY5Y neuronal cells on treatment with [D-Ala(2),N-Me-Phe(4),Gly(5)-ol]-Enkephalin, a selective ?-opioid receptor agonist. Blockade of extracellular-regulated protein kinase 1/2 (ERK1/2) with its specific inhibitor attenuated naloxone-induced CREB phosphorylation. Pretreatment with NaHS or stimulation of endogenous H2S production also significantly suppressed opioid withdrawal-induced ERK1/2 activation in mice striatum or SH-SY5Y cells. Innovation: H2S treatment is important in prevention of the development of opioid dependence via suppression of cAMP pathway in both animal and cellular models. Conclusion: Our data suggest a potential role of H2S in attenuating the development of opioid dependence, and the underlying mechanism is closely related to the inhibition of AC/cAMP pathway. Antioxid. Redox Signal. 00, 000-000.
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Single-photon-level quantum image memory based on cold atomic ensembles.
Nat Commun
PUBLISHED: 07-09-2013
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A quantum memory is a key component for quantum networks, which will enable the distribution of quantum information. Its successful development requires storage of single-photon light. Encoding photons with spatial shape through higher-dimensional states significantly increases their information-carrying capability and network capacity. However, constructing such quantum memories is challenging. Here we report the first experimental realization of a true single-photon-carrying orbital angular momentum stored via electromagnetically induced transparency in a cold atomic ensemble. Our experiments show that the non-classical pair correlation between trigger photon and retrieved photon is retained, and the spatial structure of input and retrieved photons exhibits strong similarity. More importantly, we demonstrate that single-photon coherence is preserved during storage. The ability to store spatial structure at the single-photon level opens the possibility for high-dimensional quantum memories.
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Long-term outcomes after curative resection for patients with macroscopically solitary hepatocellular carcinoma without macrovascular invasion and an analysis of prognostic factors.
Med. Oncol.
PUBLISHED: 06-25-2013
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The long-term outcome and prognostic factors after curative in patients with single hepatocellular carcinoma (HCC) without macrovascular invasion are still unclear. The objective of this study is to evaluate the effect of curative resection on survival and analyze the prognostic clinicopathologic factors, especially the presence of microvascular invasion (MVI), in these patients. Two hundred and sixty consecutive patients with single HCC without macrovascular invasion who underwent curative resection from December 2004 to December 2007 were retrospectively reviewed in this study. Survival rates were calculated by using the Kaplan-Meier method. Univariate and multivariate analyses of 14 clinicopathologic factors were performed to determine the significant prognostic factors. No patient died within 1 month after the operation. The 1-, 3-, and 5-year overall survival rates after curative resection were 96.54, 83.46, and 74.01%, respectively. Multivariate analysis revealed that only the presence of MVI was an independent negative prognostic factor affecting overall survival. The 1-, 3-, and 5-year disease-free survival rates were 79.62, 62.69, and 56.01%, respectively. The presence of MVI was the only independent unfavorable prognostic factor for disease-free survival. According to our analysis, patients with single HCC without macrovascular invasion after curative resection can be expected to have considerable long-term survival. The presence of MVI was an independent negative prognostic factor for both overall survival and disease-free survival. To improve the prognosis, these patients should be followed up more carefully and might be good candidates for adjuvant therapy.
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Viewing-angle enlargement in holographic augmented reality using time division and spatial tiling.
Opt Express
PUBLISHED: 06-06-2013
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Viewing angle enlargement is essential for SLM-based 3D holographic display. An idea of constructing equivalent-curved-SLM-array (ECSA) is proposed by linear phase factor superimposition. Employing the time division and spatial tiling (TDST) techniques, an ECSA-based horizontal 4f optical system is designed and built. The horizontal viewing angle of a single SLM is increased to 3.6 times when retaining the same hologram area. An interlaced holographic display technique is developed to remove the flicker effect. Holographic augmented reality is performed using the TDST system. Floating holographic 3D image with parallax and accommodation effects is achieved. Both TDST and interlaced technique may extend to multiple SLMs system to achieve larger viewing angle.
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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.