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Find video protocols related to scientific articles indexed in Pubmed.
In situ observation of facet-dependent oxidation of graphene on platinum in an environmental TEM.
Chem. Commun. (Camb.)
PUBLISHED: 11-20-2014
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We performed a direct observation of a crystal facet-dependent oxidation of graphene layers on platinum nanocrystals at atomic resolution in an environmental transmission electron microscope. Combined with density functional theory calculations, our work provides a novel approach for the dynamical exploration of the facet-dependent reactions at the atomic level.
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Radiofrequency ablation versus reresection in treating recurrent hepatocellular carcinoma: a meta-analysis.
Medicine (Baltimore)
PUBLISHED: 11-15-2014
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Treatment for recurrent hepatocellular carcinoma (RHCC) remains controversial. This study tried to compare survival benefits between radiofrequency ablation (RFA) and reresection for RHCC patients following curative surgical treatments.Databases were searched for comparative studies published from 2008 to 2014 on RFA versus reresection in treating RHCC. Meta-analysis was performed using a random or fixed-effect model to compare the overall survivals (OSs) and disease-free survivals (DFSs) between RFA and reresection. Begg funnel plot and Egger test were performed to assess the publication bias.Six retrospective comparative studies fulfilled our criteria and were included. For patients with RHCC, RFA was equivalent to reresection in 1-year OSs (odds ratio [OR] 0.86; 95% confidence interval [CI], 0.50-1.49; P?=?0.587), 3-year OSs (OR 0.91; 95% CI, 0.64-1.28; P?=?0.581), and 5-year OSs (OR 0.97; 95% CI, 0.69-1.36; P?=?0.846). However, reresection was superior to RFA in 3-year DFSs (OR 2.25; 95% CI, 1.37-3.68; P?=?0.001) and 5-year DFSs (OR 3.70; 95% CI, 1.98-6.93; P?=?0.000). The outcome of 1-year DFSs was unstable with statistical heterogeneity among studies included in meta-analysis (I?=?77.4%). No evidence of publication bias was found. RFA was considered as a less invasive modality for RHCC patients.RFA achieves comparable OSs as reresection in the treatment of RHCC, with lower postoperative complications.
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A multifunctional amphiphilic polymer as a platform for surface-functionalizing metallic and other inorganic nanostructures.
Faraday Discuss.
PUBLISHED: 10-08-2014
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We designed a new set of polymer ligands that combine multiple metal-coordinating groups and short polyethylene glycol (PEG) moieties in the same structure. The ligand design relies on the controlled grafting of a large number of amine-terminated histamines and PEG short chains onto a poly(isobutylene-alt-maleic anhydride) backbone, via a one-step nucleophilic addition reaction. This addition reaction is highly efficient, can be carried out in organic media and does not require additional reagents. We show that when imidazole groups are used the resulting polymer ligand can strongly ligate onto metal nanostructures such as nanoparticles (NPs) and nanorods (NRs) made of gold cores. The resulting polymer-coated NPs and NRs exhibit good colloidal stability to pH changes and added electrolytes. This constitutes a departure from the use of thiol-based ligands to coordinate on Au surfaces. The present chemical approach also opens up additional opportunities for designing hydrophilic and reactive platforms where the polymer coating can be adjusted to various metal and metal oxide surfaces by simply modifying or combining the addition reaction with other metal coordinating groups. These could include iron oxide NPs and semiconductor QDs. These polymer-capped NPs and NRs can be used to develop biologically-active platforms with potential use for drug delivery and sensing.
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Roles of TGF-?/Smad signaling pathway in pathogenesis and development of gluteal muscle contracture.
Connect. Tissue Res.
PUBLISHED: 09-11-2014
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Abstract Purpose of the study: Gluteal muscle contracture (GMC) is a chronic fibrotic disease of gluteal muscles which is characterized by excessive deposition of collagen in the extracellular matrix. Transforming growth factor (TGF)-?s have been shown to play an important role in the progression of GMC. However, the underlying mechanisms are not entirely clear. We sought to explore the expression of TGF-?/Smad pathway proteins and their downstream targets in gluteal muscle contracture disease. Materials and methods: The expression levels of collagens type I/III, TGF-?1, Smad2/3/4/7 and PAI-1 (plasminogen activator inhibitor type 1) in gluteal muscle contraction (GMC) patients were measured using immunohistochemistry, reverse transcription and polymerase chain reaction (RT-PCR) and western blot assays. Results: The expressions of collagens type I/III and TGF-?1 were significantly increased in the contraction band compared with unaffected muscle. In addition, R-Smad phosphorylation and Smad4 protein expression in the contraction band were also elevated, while the expression of Smad7 was significantly decreased in the fibrotic muscle of the GMC patients compared to the unaffected adjacent muscle. The protein and mRNA levels of PAI-1 were also remarkably increased in the contraction band compared with adjacent muscle. Immunohistochemical analysis also demonstrated that the expression levels of TGF-?1 and PAI-1 were higher in contraction band than those in the adjacent muscle. Conclusion: Our data confirm the stimulating effects of the TGF-?/Smad pathway in gluteal muscle contracture disease and reveal the internal changes of TGF-?/Smad pathway proteins and their corresponding targets in gluteal muscle contracture patients.
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Absence of protective effect of oral contraceptive use on the development of rheumatoid arthritis: a meta-analysis of observational studies.
Int J Rheum Dis
PUBLISHED: 09-09-2014
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To investigate the association between oral contraceptive (OC) use and development of rheumatoid arthritis (RA).
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Similar prognoses for invasive micropapillary breast carcinoma and pure invasive ductal carcinoma: a retrospectively matched cohort study in China.
PLoS ONE
PUBLISHED: 09-04-2014
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Invasive micropapillary breast carcinoma (IMPC) is a rare pathological finding. Few studies have compared IMPC with invasive ductal breast carcinoma (IDC) according to matched nodal status and age. To better illustrate the difference between IMPC and IDC prognoses, we conducted this cohort study.
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The receptor kinase CERK1 has dual functions in symbiosis and immunity signalling.
Plant J.
PUBLISHED: 09-03-2014
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The establishment of symbiotic interactions between mycorrhizal fungi, rhizobial bacteria and their legume hosts involves a common symbiosis signalling pathway. This signalling pathway is activated by Nod factors produced by rhizobia and these are recognised by the Nod factor receptors NFR1/LYK3 and NFR5/NFP. Mycorrhizal fungi produce lipochitooligosaccharides (LCOs) similar to Nod factors, as well as short-chain chitin oligomers (CO4/5), implying commonalities in signalling during mycorrhizal and rhizobial associations. Here we show that NFR1/LYK3, but not NFR5/NFP, is required for the establishment of the mycorrhizal interaction in legumes. NFR1/LYK3 is necessary for the recognition of mycorrhizal fungi and the activation of the symbiosis signalling pathway leading to induction of calcium oscillations and gene expression. Chitin oligosaccharides also act as microbe associated molecular patterns that promote plant immunity via similar LysM receptor-like kinases. CERK1 in rice has the highest homology to NFR1 and we show that this gene is also necessary for the establishment of the mycorrhizal interaction as well as for resistance to the rice blast fungus. Our results demonstrate that NFR1/LYK3/OsCERK1 represents a common receptor for chitooligosaccharide-based signals produced by mycorrhizal fungi, rhizobial bacteria (in legumes) and fungal pathogens. It would appear that mycorrhizal recognition has been conserved in multiple receptors across plant species, but additional diversification in certain plant species has defined other signals that this class of receptors can perceive. This article is protected by copyright. All rights reserved.
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Elasticity of Fractal Inspired Interconnects.
Small
PUBLISHED: 09-02-2014
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The use of fractal-inspired geometric designs in electrical interconnects represents an important approach to simultaneously achieve large stretchability and high aerial coverage of active devices for stretchable electronics. The elastic stiffness of fractal interconnects is determined analytically in this paper. Specifically, the elastic energy and the tensile stiffness for an order n fractal interconnect of arbitrary shape are obtained, and are verified by the finite element analysis and experiments.
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Primary malignant melanoma of the vagina: a retrospective clinicopathologic study of 44 cases.
Int. J. Gynecol. Cancer
PUBLISHED: 08-26-2014
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This study aimed to identify prognostic factors of survival and improve treatment strategies in women diagnosed with primary malignant melanoma of the vagina.
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MiR-663 inhibits radiation-induced bystander effects by targeting TGFB1 in a feedback mode.
RNA Biol
PUBLISHED: 08-22-2014
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The mechanisms of radiation-induced bystander effects (RIBE) have been investigated intensively over the past two decades. Although quite a few reports demonstrated that cytokines such as TGF-?1 are induced within the directly irradiated cells and play critical roles in mediating the bystander effects, little is known about the signaling pathways that occur in bystander cells. The crucial question as to why RIBE signals cannot be infinitely transmitted, therefore, remains unclear. In the present study, we showed that miR-663, a radiosensitive microRNA, participates in the regulation of biological effects in both directly irradiated and bystander cells via its targeting of TGF-?1. MiR-663 was downregulated, while TGFB1 was upregulated in directly irradiated cells. The regulation profile of miR-663 and TGFB1, on the other hand, was reversed in bystander cells, in which an elevated miR-663 expression was exhibited and led to downregulation of TGF-?1. Further studies revealed that miR-663 interacts with TGFB1 directly and that through its binding to the core regulation sequence, miR-663 suppresses the expression of TGFB1. Based on the results, we propose that miR-663 inhibits the propagation of RIBE in a feedback mode, in which the induction of TGF-?1 by reduced miR-663 in directly irradiated cells leads to increased level of miR-663 in bystander cells. The upregulation of miR-663 in turn suppresses the expression of TGF-?1 and limited further transmission of the bystander signals.
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Microfluidic serpentine antennas with designed mechanical tunability.
Lab Chip
PUBLISHED: 08-22-2014
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This paper describes the design and characterization of microfluidic serpentine antennas with reversible stretchability and designed mechanical frequency modulation (FM). The microfluidic antennas are designed based on the Poisson's ratio of the elastomer in which the liquid alloy antenna is embedded, to controllably decrease, stabilize or increase its resonance frequency when being stretched. Finite element modelling was used in combination with experimental verification to investigate the effects of substrate dimensions and antenna aspect ratios on the FM sensitivity to uniaxial stretching. It could be designed within the range of -1.2 to 0.6 GHz per 100% stretch. When the aspect ratio of the serpentine antenna is between 1.0 and 1.5, the resonance frequency is stable under stretching, bending, and twisting. The presented microfluidic serpentine antenna design could be utilized in the field of wireless mobile communication for the design of wearable electronics, with a stable resonance frequency under dynamic applied strain up to 50%.
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Development and validation of a prediction score for complications after hepatectomy in hepatitis B-related hepatocellular carcinoma patients.
PLoS ONE
PUBLISHED: 08-15-2014
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The aim of the present study was to develop and validate a prediction score for postoperative complications by severity and guide perioperative management and patient selection in hepatitis B-related hepatocellular carcinoma patients undergoing liver resection.
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Down-regulation of BTG1 by miR-454-3p enhances cellular radiosensitivity in renal carcinoma cells.
Radiat Oncol
PUBLISHED: 08-12-2014
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B cell translocation gene 1 (BTG1) has long been recognized as a tumor suppressor gene. Recent reports demonstrated that BTG1 plays an important role in progression of cell cycle and is involved in cellular response to stressors. However, the microRNAs mediated regulatory mechanism of BTG1 expression has not been reported so far. MicroRNAs can effectively influence tumor radiosensitivity by preventing cell cycle progression, resulting in enhancement of the cytotoxicity of radiotherapy efficacy. This study aimed to demonstrating the effects of microRNAs on the BTG1 expression and cellular radiosensitivity.
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In situ polymerization deposition of porous conducting polymer on reduced graphene oxide for gas sensor.
ACS Appl Mater Interfaces
PUBLISHED: 08-12-2014
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Porous conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) nanocomposite prepared on reduced graphene oxide (RGO) film was used as efficient chemiresistor sensor platform for NO2 detection. The comparable electrical performance between RGO and porous PEDOT nanostructure, the large surface area and opening porous structure of this RGO/porous PEDOT nanocomposite resulted in excellent synergistic effect. The gas sensing performance revealed that, in contrast to bare RGO, the RGO/porous PEDOT exhibited the enhanced sensitivity (2 orders of magnitude) as well as response and recovery performance. As a result of the highly uniform distribution of PEDOT porous network and excellent synergetic effect between RGO and porous PEDOT, this nanocomposite based sensor exhibited higher selectivity to NO2 in contrast to other oxidant analyte gases, e.g., HCl, H2S and SO2.
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Ultrafast quenching of electron-boson interaction and superconducting gap in a cuprate superconductor.
Nat Commun
PUBLISHED: 08-11-2014
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Ultrafast spectroscopy is an emerging technique with great promise in the study of quantum materials, as it makes it possible to track similarities and correlations that are not evident near equilibrium. Thus far, however, the way in which these processes modify the electron self-energy--a fundamental quantity describing many-body interactions in a material--has been little discussed. Here we use time- and angle-resolved photoemission to directly measure the ultrafast response of self-energy to near-infrared photoexcitation in high-temperature cuprate superconductor. Below the critical temperature of the superconductor, ultrafast excitations trigger a synchronous decrease of electron self-energy and superconducting gap, culminating in a saturation in the weakening of electron-boson coupling when the superconducting gap is fully quenched. In contrast, electron-boson coupling is unresponsive to ultrafast excitations above the critical temperature of the superconductor and in the metallic state of a related material. These findings open a new pathway for studying transient self-energy and correlation effects in solids.
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Sharp low-energy feature in single-particle spectra due to forward scattering in d-wave cuprate superconductors.
Phys. Rev. Lett.
PUBLISHED: 07-29-2014
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There is an enormous interest in the renormalization of the quasiparticle (qp) dispersion relation of cuprate superconductors both below and above the critical temperature T_{c} because it enables the determination of the fluctuation spectrum to which the qp's are coupled. A remarkable discovery by angle-resolved photoemission spectroscopy (ARPES) is a sharp low-energy feature (LEF) in qp spectra well below the superconducting energy gap but with its energy increasing in proportion to T_{c} and its intensity increasing sharply below T_{c}. This unexpected feature needs to be reconciled with d-wave superconductivity. Here, we present a quantitative analysis of ARPES data from Bi_{2}Sr_{2}CaCu_{2}O_{8+?} (Bi2212) using Eliashberg equations to show that the qp scattering rate due to the forward scattering impurities far from the Cu-O planes is modified by the energy gap below T_{c} and shows up as the LEF. This is also a necessary step to analyze ARPES data to reveal the spectrum of fluctuations promoting superconductivity.
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Speeding of spherulitic growth rate at the late stage of isothermal crystallization due to interfacial diffusion for double-layer semicrystalline polymer films.
J Phys Chem B
PUBLISHED: 07-23-2014
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In this study a unique phenomenon has been found for isothermal crystallization of double-layer semicrystalline polymer films. It is surprisingly found that there exists a speeding of poly(l-lactic acid) (PLA) spherulitic growth rate for poly(ethylene oxide)/poly(l-lactic acid) (PEO/PLA) double-layer films at the late stage of isothermal crystallization, which does not exist for PLA/PEO blend films and neat PLA films. The mutual diffusion between PEO and PLA layers plays the key factor to bring out the observed speeding of spherulitic growth rate. This type of study provides an avenue for understanding the interplay between polymer crystallization and interfacial diffusion in multilayer polymer films, which is not available when employing the polymer blend films.
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Strategies for interfacing inorganic nanocrystals with biological systems based on polymer-coating.
Chem Soc Rev
PUBLISHED: 07-17-2014
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Interfacing inorganic nanoparticles and biological systems with the aim of developing novel imaging and sensing platforms has generated great interest and much activity. However, the effectiveness of this approach hinges on the ability of the surface ligands to promote water-dispersion of the nanoparticles with long term colloidal stability in buffer media. These surface ligands protect the nanostructures from the harsh biological environment, while allowing coupling to target molecules, which can be biological in nature (e.g., proteins and peptides) or exhibit specific photo-physical characteristics (e.g., a dye or a redox-active molecule). Amphiphilic block polymers have provided researchers with versatile molecular platforms with tunable size, composition and chemical properties. Hence, several groups have developed a wide range of polymers as ligands or micelle capsules to promote the transfer of a variety of inorganic nanomaterials to buffer media (including magnetic nanoparticles and semiconductor nanocrystals) and render them biocompatible. In this review, we first summarize the established synthetic routes to grow high quality nanocrystals of semiconductors, metals and metal oxides. We then provide a critical evaluation of the recent developments in the design, optimization and use of various amphiphilic copolymers to surface functionalize the above nanocrystals, along with the strategies used to conjugate them to target biomolecules. We finally conclude by providing a summary of the most promising applications of these polymer-coated inorganic platforms in sensor design, and imaging of cells and tissues.
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Association between adult weight gain and colorectal cancer: A dose-response meta-analysis of observational studies.
Int. J. Cancer
PUBLISHED: 07-15-2014
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Our study investigated the association between adult weight gain and risk of colorectal cancer (CRC). Using terms related to weight gain and CRC, we searched PubMed, Embase, and Web of Science for relevant studies published before June 2014. Two evaluators independently selected studies according to selection criteria, and 8 studies were included (3case-control and 5 cohort studies). Summary estimates were obtained using fixed- or random-effects models. The risk ratio (RR) of the association between adult weight gain and CRC was 1.25 (95% confidence interval [CI], 1.10 to 1.43); the RR was 1.30 (95% CI, 1.14 to 1.49) for colon cancer (CC) and 1.27 (95% CI, 1.02 to 1.58) for rectal cancer (RC) for the highest versus lowest category. The risk increased by 5% (RR, 1.05; 95% CI, 1.02 to 1.09) for every 5-kg increase in adult weight for CRC; the risk increased by 6% (RR, 1.06; 95% CI, 1.02 to 1.11) for CC and 6% (RR, 1.06; 95% CI, 1.03 to 1.08) for RC. The subgroup analyses showed a positive association between adult weight gain and risk of CRC only in men, and the RR was 1.65(95% CI, 1.42 to 1.92) for the highest versus lowest category of adult weight gain and 1.10 (95% CI, 1.06 to 1.15) for a 5-kg increase in adult weight. In conclusion, there is evidence that adult weight gain is associated with an increased risk of CRC. However, the positive association between adult weight gain and risk of CRC is stronger among men than women. This article is protected by copyright. All rights reserved.
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In situ formation of oxygen vacancy in perovskite Sr0.95Ti0.8Nb0.1M0.1O3 (M = Mn, Cr) toward efficient carbon dioxide electrolysis.
Sci Rep
PUBLISHED: 07-11-2014
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In this work, redox-active Mn or Cr is introduced to the B site of redox stable perovskite Sr0.95Ti0.9Nb0.1O3.00 to create oxygen vacancies in situ after reduction for high-temperature CO2 electrolysis. Combined analysis using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric analysis confirms the change of the chemical formula from oxidized Sr0.95Ti0.9Nb0.1O3.00 to reduced Sr0.95Ti0.9Nb0.1O2.90 for the bare sample. By contrast, a significant concentration of oxygen vacancy is additionally formed in situ for Mn- or Cr-doped samples by reducing the oxidized Sr0.95Ti0.8Nb0.1M0.1O3.00 (M = Mn, Cr) to Sr0.95Ti0.8Nb0.1M0.1O2.85. The ionic conductivities of the Mn- and Cr-doped titanate improve by approximately 2 times higher than bare titanate in an oxidizing atmosphere and 3-6 times higher in a reducing atmosphere at intermediate temperatures. A remarkable chemical accommodation of CO2 molecules is achieved on the surface of the reduced and doped titanate, and the chemical desorption temperature reaches a common carbonate decomposition temperature. The electrical properties of the cathode materials are investigated and correlated with the electrochemical performance of the composite electrodes. Direct CO2 electrolysis at composite cathodes is investigated in solid-oxide electrolyzers. The electrode polarizations and current efficiencies are observed to be significantly improved with the Mn- or Cr-doped titanate cathodes.
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Identification and Characterization of Small-Molecule Inhibitors of the R132H/R132H Mutant Isocitrate Dehydrogenase 1 Homodimer and R132H/Wild-Type Heterodimer.
J Biomol Screen
PUBLISHED: 06-30-2014
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Recurrent genetic mutations in isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) have been identified in multiple tumor types. The most frequent mutation, IDH1 R132H, is a gain-of-function mutation resulting in an enzyme-catalyzing conversion of ?-ketoglutarate (?-KG) to 2-hydroxyglutarate (2-HG). A high-throughput assay quantifying consumption of NADPH by IDH1 R132H has been optimized and implemented to screen 3 million compounds in 1536-well formats. The primary high-throughput screening hits were further characterized by RapidFire-mass spectrometry measuring 2-HG directly. Multiple distinct chemotypes were identified with nanomolar potencies (6-300 nM). All inhibitors were found to be inactive against the wild-type IDH1 homodimers. An IDH1 heterodimer between wild-type and R132H mutant is capable of catalyzing conversion of ?-KG to 2-HG and isocitrate to ?-KG. Interestingly, one of the inhibitors, EXEL-9324, was found to inhibit both conversions by the IDH1 heterodimer. This indicates the R132H/WT heterodimer may adopt conformations distinct from that of the R132H/R132H homodimer. Further enzymatic studies support this conclusion as the heterodimer exhibited a significantly lower apparent Michaelis-Menten constant for ?-KG (Km =110 µM) compared with the R132H homodimer (Km = 1200 µM). The enhanced apparent affinity for ?-KG suggests R132H/WT heterodimeric IDH1 can produce 2-HG more efficiently at normal intracellular levels of ?-KG (approximately 100 µM).
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Septic arthritis caused by Brucella melitensis in urban Shenzhen, China: a case report.
J Med Case Rep
PUBLISHED: 06-14-2014
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Brucellosis is a systemic infectious disease which is still a challenging medical problem in rural areas such as northern China. It rarely occurs in urban areas such as Shenzhen in southern China. Osteoarticular involvements are frequently seen in brucellosis, and rarely is arthritis the only clinical presentation. We report a case of hip septic arthritis caused by Brucella melitensis in an urban area of Shenzhen, China.
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[Metastases to the breast from non-mammary malignancies: a clinicopathologic study of 28 cases].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 06-12-2014
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To investigate the clinicopathologic characteristics and differential diagnosis of the metastases to the breast from non-mammary malignancies.
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[Assessment of HER2 gene amplification in breast cancer: a comparison of dual-color in-situ hybridization and fluorescence in-situ hybridization].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 06-12-2014
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To compare dual-color in-situ hybridization (DISH) with fluorescence in situ hybridization(FISH) in evaluating the human HER2 gene status in invasive breast cancer.
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Effect of replacement of Ca by Zn on the structure and optical property of CaTiO3 :Eu(3+) red phosphor prepared by sol-gel method.
Luminescence
PUBLISHED: 06-05-2014
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Eu(3+) -doped calcium titanate red phosphors, Ca1-x Znx TiO3 :Eu(3+) , were prepared by the sol-gel method. The structure of prepared Ca1-x Znx TiO3 :Eu(3+) phosphors were investigated by X-ray diffraction and infrared spectra. Due to the (5) D0 ???(7) F1-3 electron transitions of Eu(3+) ions, photoluminescence spectra showed a red emission at about 619 nm under excitation of 397 nm and 465 nm, respectively. When zinc was added to the host, the luminescent intensity of Ca1-x Znx TiO3 :Eu(3+) was markedly improved several fold compared with that of CaTiO3 :Eu(3+) . Ca0.9 Zn0.1 TiO3 :Eu(3+) also had higher luminescence intensity than the commercially available Y2 O3 :Eu(3+) phosphors under UV light excitation. Copyright © 2014 John Wiley & Sons, Ltd.
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Cloning and optimization of a nisin biosynthesis pathway for bacteriocin harvest.
ACS Synth Biol
PUBLISHED: 05-21-2014
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Nisin is an important antimicrobial peptide that has enormous applications in biotechnology. Despite many encouraging efforts, its overproduction has been a long-standing challenge due to the complexity of the underlying pathway and the difficulty in genetic modification of lactic acid bacteria. Here, we cloned an entire nisin biosynthesis pathway from a nisin-producing strain (Lactococcus lactis K29) into a plasmid and transplanted the plasmid into a nisin deficient strain Lactococcus lactis MG1363, resulting in successful heterologous expression of bioactive recombinant nisin. To increase nisin harvest, we also overexpressed nisA, a gene responsible for nisin precursor production, with a set of constitutive promoters. To further optimize nisin yield, we minimized the metabolic cost of the engineered strains by integrating nisA overexpression cassettes and the recombinant pathway into a single circuit. With our rational construction and optimization, our engineered optimized strain is able to produce bioactive nisin with a yield of 1098 IU/mL, which is more than six times higher than that of the original strain.
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Design of a multi-dopamine-modified polymer ligand optimally suited for interfacing magnetic nanoparticles with biological systems.
Langmuir
PUBLISHED: 05-20-2014
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We have designed a set of multifunctional and multicoordinating polymer ligands that are optimally suited for surface functionalizing iron oxide and potentially other magnetic nanoparticles (NPs) and promoting their integration into biological systems. The amphiphilic polymers are prepared by coupling (via nucleophilic addition) several amine-terminated dopamine anchoring groups, poly(ethylene glycol) moieties, and reactive groups onto a poly(isobutylene-alt-maleic anhydride) (PIMA) chain. This design greatly benefits from the highly efficient and reagent-free one-step reaction of maleic anhydride groups with amine-containing molecules. The availability of several dopamine groups in the same ligand greatly enhances the ligand affinity, via multiple coordination, to the magnetic NPs, while the hydrophilic and reactive groups promote colloidal stability in buffer media and allow subsequent conjugation with target biomolecules. Iron oxide nanoparticles ligand exchanged with these polymer ligands have a compact hydrodynamic size and exhibit enhanced long-term colloidal stability over the pH range of 4-12 and in the presence of excess electrolytes. Nanoparticles ligated with terminally reactive polymers have been easily coupled to target dyes and tested in live cell imaging with no measurable cytotoxicity. Finally, the resulting hydrophilic nanoparticles exhibit large and size-dependent r2 relaxivity values.
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MEP Pathway-mediated isopentenol production in metabolically engineered Escherichia coli.
Microb. Cell Fact.
PUBLISHED: 05-19-2014
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BackgroundIsopentenols, such as prenol and isoprenol, are promising advanced biofuels because of their higher energy densities and better combustion efficiencies compared with ethanol. Microbial production of isopentenols has been developed recently via metabolically engineered E. coli. However, current yields remain low and the underlying pathways require systematic optimization.ResultsIn this study, we targeted the E. coli native 2-methyl-(D)-erythritol-4-phosphate (MEP) pathway and its upstream glycolysis pathway for the optimization of isopentenol production. Two codon optimized genes, nudF and yhfR from Bacillus subtilis, were synthesized and expressed in E. coli W3110 to confer the isopentenol production of the strain. Two key enzymes (IspG and Dxs) were then overexpressed to optimize the E. coli native MEP pathway, which led to a significant increase (3.3-fold) in isopentenol production. Subsequently, the glycolysis pathway was tuned to enhance the precursor and NADPH supplies for the MEP pathway by activating the pentose phosphate pathway (PPP) and Entner-Doudoroff pathway (ED), which resulted in additional 1.9 folds of increase in isopentenol production. A 5 L-scale batch cultivation experiment was finally implemented, showing a total of 61.9 mg L¿1 isopentenol production from 20 g L¿1 of glucose.ConclusionThe isopentenol production was successfully increased through multi-step optimization of the MEP and its upstream glycolysis pathways. It demonstrated that the total fluxes and their balance of the precursors of the MEP pathway are of critical importance in isopentenol production. In the future, an elucidation of the contribution of PPP and ED to MEP is needed for further optimization of isopentenol production.
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Cisplatin and gemcitabine as the first line therapy in metastatic triple negative breast cancer.
Int. J. Cancer
PUBLISHED: 04-25-2014
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No standard first-line treatment exists for patients with metastatic triple-negative breast cancer (mTNBC). In this single-arm, phase II study (NCT00601159), we evaluated the efficacy and tolerability of cisplatin and gemcitabine (GP) as the first-line therapy in mTNBC. Eligible women were those who had measurable disease with no prior chemotherapy for mTNBC. All patients received 21-day-cycle of cisplatin 25 mg/m(2) on days 1-3 and gemcitabine 1,000 mg/m(2) on days 1 and 8. Treatment was continued until disease progression, unacceptable toxicity or up to 8 cycles. BRCA1/2 mutation status and immunohistochemical basal markers were included in the correlative studies. Sixty-four patients with the median age of 49 years were enrolled. Thirty patients (46.9%) had ?1 year from diagnosis to recurrence. The median progression free survival (PFS) was 7.2 months (95%CI, 5.6-8.9 months) and overall survival (OS) was 19.1 months (95%CI, 12.4-25.8 months) with median follow-up 42 months. Patients received treatment for a median of six cycles. The overall response rate was 62.5%. The most common grades 3/4 toxicities were neutropenia (42.2%), thrombocytopenia (29.7%), anemia (18.8%) and nausea/vomiting (15.6%).No specific BRCA1/2 mutation carriers were identified. The efficacy of responses and basal-like subtype were independent favorable factors for PFS and OS, respectively. We conclude that the combination of GP has significant activity and a favorable safety profile as the first-line chemotherapy in mTNBC patients, in particular patients with basal-like subtype. The promising role of this combination as the front-line treatment for mTNBC continued to be evaluated in our ongoing phase III trial (CBCSG006).
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Nanotwinned diamond with unprecedented hardness and stability.
Nature
PUBLISHED: 04-15-2014
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Although diamond is the hardest material for cutting tools, poor thermal stability has limited its applications, especially at high temperatures. Simultaneous improvement of the hardness and thermal stability of diamond has long been desirable. According to the Hall-Petch effect, the hardness of diamond can be enhanced by nanostructuring (by means of nanograined and nanotwinned microstructures), as shown in previous studies. However, for well-sintered nanograined diamonds, the grain sizes are technically limited to 10-30?nm (ref. 3), with degraded thermal stability compared with that of natural diamond. Recent success in synthesizing nanotwinned cubic boron nitride (nt-cBN) with a twin thickness down to ?3.8?nm makes it feasible to simultaneously achieve smaller nanosize, ultrahardness and superior thermal stability. At present, nanotwinned diamond (nt-diamond) has not been fabricated successfully through direct conversions of various carbon precursors (such as graphite, amorphous carbon, glassy carbon and C60). Here we report the direct synthesis of nt-diamond with an average twin thickness of ?5?nm, using a precursor of onion carbon nanoparticles at high pressure and high temperature, and the observation of a new monoclinic crystalline form of diamond coexisting with nt-diamond. The pure synthetic bulk nt-diamond material shows unprecedented hardness and thermal stability, with Vickers hardness up to ?200?GPa and an in-air oxidization temperature more than 200?°C higher than that of natural diamond. The creation of nanotwinned microstructures offers a general pathway for manufacturing new advanced carbon-based materials with exceptional thermal stability and mechanical properties.
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[Clinicopathologic features of cystic hypersecretory lesion of the breast].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 04-10-2014
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To study the clinicopathologic features, immunophenotype and differential diagnosis of cystic hypersecretory lesion (CHL) of the breast.
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MRI characteristics of intraductal papilloma.
Acta Radiol
PUBLISHED: 04-02-2014
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Intraductal papilloma (IDP) is the most common pathological finding in women with pathological nipple discharge. Magnetic resonance imaging (MRI) has shown potential for characterizing breast tumors; however, MRI findings of IDPs are inconclusive, and certain diagnostic standards are lacking. Purpose: To characterize the MRI features of IDP from a relatively large cohort.
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Hydrothermal preparation of hybrid carbon/silica monolithic capillary column for liquid chromatography.
J Sep Sci
PUBLISHED: 03-20-2014
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A simple, easy and economical approach for the preparation of a hybrid carbon/silica monolithic capillary column was described for the first time by using silica monolith as framework in combination with hydrothermal carbonization at 180°C. During the preparation process, formamide was introduced to the reaction solutions to reduce the dissolution rate of monolithic silica skeleton and its optimal concentration was 1.5 M. Fourier transform infrared spectrometry, scanning electron microscopy, energy dispersive X-ray spectrometry, and inverse size exclusion chromatography were carried out to characterize the as-prepared column. The results demonstrated that carbon spheres ranging from 150 to 1000 nm were successfully attached to the surface of silica skeleton. The prepared hybrid carbon/silica column had a permeability of 4.4 × 10(-14) m(2). Chromatographic performance of the column was evaluated by separation of various compounds including alkylbenzenes, nucleosides and bases, and aromatic acids. The column exhibited an efficiency of 75,000 plates/m for butylbenzene at the optimal linear velocity of 0.23 mm/s. The successful separation of these compounds and the study on mechanism indicated that the column can be applied in mixed-mode chromatography.
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Association between calcium channel blockers and breast cancer: a meta-analysis of observational studies.
Pharmacoepidemiol Drug Saf
PUBLISHED: 03-19-2014
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To investigate the association between calcium channel blockers (CCBs) and increased risk of breast cancer.
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Invasive breast carcinomas of no special type with osteoclast-like giant cells frequently have a luminal phenotype.
Virchows Arch.
PUBLISHED: 03-17-2014
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Invasive carcinoma of no special type (NST) with osteoclast-like giant cells (OGCs) represents a unique type of breast neoplasm, characterized by the presence of multinucleated OGCs and a vascularized, hemorrhagic stroma. Because of its rarity, the literature regarding this tumor remains limited and a detailed immunophenotype of this tumor has not been established as yet. We report a clinicopathological and immunohistochemical study of 42 patients with invasive carcinoma NST with OGCs. Macroscopically, these tumors presented as a well-delimited red-brown mass. A remarkable feature of the tumor was the presence of OGCs in the fibroblastic or hemorrhagic vascular stroma, as well as in the adjacent tumor nests or glandular lumina. The number of OGCs varied from 8 to 105 per 10 high-power fields with an average of 48. The tumors were well to moderately differentiated. Cribriform architecture was observed in 27 tumors (63 %). All of the 36 available tumors were of luminal phenotype, according to the Ki67 labeling index 89 % luminal A and 11 % luminal B. With a mean follow-up time of 46.4 months, lung metastasis was found in 2 patients (5 %) at 7 and 11 years after the operation, respectively. None of the other cases had presented with evidence of recurrence or metastasis. To the best of our knowledge, this is the largest reported series of invasive carcinoma NST with OGCs as yet. Our study revealed that invasive carcinoma NST with OGCs exhibit a luminal phenotype with luminal A subtype as the major group.
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Functionalizing single crystals: incorporation of nanoparticles inside gel-grown calcite crystals.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 03-12-2014
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Synthetic single crystals are usually homogeneous solids. Biogenic single crystals, however, can incorporate biomacromolecules and become inhomogeneous solids so that their properties are also extrinsically regulated by the incorporated materials. The discrepancy between the properties of synthetic and biogenic single crystals leads to the idea to modify the internal structure of synthetic crystals to achieve nonintrinsic properties by incorporation of foreign material. Intrinsically colorless and diamagnetic calcite single crystals are turned into colored and paramagnetic solids, through incorporation of Au and Fe3O4 nanoparticles without significantly disrupting the crystalline lattice of calcite. The crystals incorporate the nanoparticles and gel fibers when grown in agarose gel media containing the nanoparticles, whereas the solution-grown crystals do not. As such, our work extends the long-history gel method for crystallization into a platform to functionalize single-crystalline materials.
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Transforming growth factor-?1 and ?-smooth muscle actin in stromal fibroblasts are associated with a poor prognosis in patients with clinical stage I-IIIA nonsmall cell lung cancer after curative resection.
Tumour Biol.
PUBLISHED: 03-10-2014
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The aims of this study were to investigate the expression of transforming growth factor-?1 (TGF-?1) and ?-smooth muscle actin (?-SMA) in surgical resection specimens from nonsmall cell lung cancer (NSCLC) and to evaluate the prognostic significance of this gene expression in stromal fibroblasts for patients with clinical stage I-IIIA NSCLC. The immunohistochemical expression of TGF-?1 and ?-SMA was evaluated in 78 formalin-fixed paraffin-embedded tumor specimens from clinical stage I-IIIA NSCLC. Correlations between this gene expression and the clinicopathologic characteristics were determined by chi-square test. The prognostic impact of this gene expression in stromal fibroblasts with regard to overall survival (OS) was determined by Kaplan-Meier and Cox hazard proportional model. The percentages of high TGF-?1 expression in stromal fibroblasts and cancer cells were 19.2 % (15/78) and 35.9 % (28/78), respectively. There were 28.2 % (22/78) of patients with high ?-SMA expression in stromal fibroblasts. The analysis revealed a significant positive association between TGF-?1 expression in stromal fibroblasts and in cancer cells (? (2)?= 4.86, p = 0.03). No significant association was found between TGF-?1 in cancer cells and ?-SMA expression in stromal fibroblasts (? (2)?= 0.978, p = 0.326). The 3-year OS rates with low and high TGF-?1 expression in stromal fibroblasts were 52.4 and 26.7 %, respectively (? (2)?= 5.42, p = 0.019). The 3-year OS rates with low and high ?-SMA expression in stromal fibroblasts were 53.9 and 31.0 %, respectively (? (2)?=5.01, p=0.025). The multivariate analysis revealed that clinical stage and TGF-?1 and ?-SMA expression levels in stromal fibroblasts were identified as independent predictive factors of OS. The results suggest that the expression level of TGF-?1 and ?-SMA in stromal fibroblasts may have prognostic significance in patients with clinical stage I-IIIA NSCLC after curative resection.
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High sensitivity of touch imprint cytology in young patients with invasive lobular carcinoma of the breast.
Tumour Biol.
PUBLISHED: 02-13-2014
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Invasive lobular carcinoma (ILC) of the breast is a rare type of breast cancer. Metastatic ILC is difficult to identify in sentinel lymph nodes (SLNs) because of its low-grade cytomorphology and its tendency to resemble lymphocytes. Touch imprint cytology (TIC) is a rapid method for evaluating SLNs intraoperatively. We sought to evaluate this technique in the identification of SLN metastases in ILC. A total of 230 SLNs from 88 patients diagnosed with ILC were examined with TIC, and the results were compared with their histological diagnosis. We first confirmed some typical cytological features of SLN metastases in ILC such as a thick eosinophilic background and hyperplasia of small cell lacking adhesion. Further analysis showed that sensitivity of TIC was 60.5 % on per-node basis and 58.3 % on per-patient basis; specificity of TIC was 100 % on per-node basis and 100 % on per-patient basis. Interestingly, when we divided patients according to their ages, the sensitivity of TIC in patients younger than 50 years old greatly increased to 90.9 % on per-node basis and 85.7 % on per-patient basis, whereas the specificity remained 100 % on both per-node basis and per-patient basis. However, different tumor sizes did not clearly change the sensitivity of TIC compared to the overall sensitivity. Patients with tumor size bigger than 1 cm revealed a TIC sensitivity of 59.4 % on per-node basis and 55.0 % on per-patient basis. These results suggest that TIC can be used as a reliable method of detecting SLN metastasis only in young patients with ILC.
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Non-wrinkled, highly stretchable piezoelectric devices by electrohydrodynamic direct-writing.
Nanoscale
PUBLISHED: 02-07-2014
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Piezoelectric structures, in forms that allow mere in-surface deformations under large strains, are attractive for bio-integrated systems. Here, mechano-electrospinning (MES) is presented to direct-write straight nanofibers of polyvinylidene fluoride onto a prestrained poly(dimethylsiloxane) (PDMS) substrate, to position and polarize a piezoelectric nanofiber array in one-step. Wrinkled/non-wrinkled buckling modes are found when the substrates are released, and the morphology of the direct-written fiber proved the key to determine the buckling modes, which can be tuned precisely by MES parameters. The non-wrinkled, stretchable piezoelectric devices with a highly synchronized serpentine fiber array exhibit their in-surface deformation and stable piezoelectric performance up the failure strain of PDMS (?110% in our study), which may be used as stretchable sensors and energy converters/providers.
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Reconstructing middle hepatic vein tributaries in right-lobe living donor liver transplantation.
Dig Surg
PUBLISHED: 01-20-2014
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To investigate the effectiveness of our technique and policy in reconstructing middle hepatic vein (MHV) tributaries of patients undergoing right-lobe living donor liver transplantation (LDLT).
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SREBP-1c overexpression induces triglycerides accumulation through increasing lipid synthesis and decreasing lipid oxidation and VLDL assembly in bovine hepatocytes.
J. Steroid Biochem. Mol. Biol.
PUBLISHED: 01-20-2014
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The natural incidence of fatty liver in ruminants is significantly higher than in monogastric animals. Fatty liver is associated with sterol regulatory element-binding protein 1c (SREBP-1c). The aim of this study was to investigate the regulatory network effects of SREBP-1c on the lipid metabolic genes involved in fatty acid uptake, activation, oxidation, synthesis, and very low-density lipoprotein (VLDL) assembly in bovine hepatocytes. In vitro, bovine hepatocytes were transfected with an adenovirus-mediated SREBP-1c overexpression vector. SREBP-1c overexpression significantly up-regulated the expression and activity of the fatty acid uptake, activation, and synthesis enzymes: liver fatty acid binding protein, fatty acid translocase, acyl-CoA synthetase long-chain 1, acetyl-CoA carboxylase 1, and fatty acid synthase, increasing triglyceride (TG) synthesis and accumulation. SREBP-1c overexpression down-regulated the expression and activity of the lipid oxidation enzymes: carnitine palmitoyltransferase 1 and carnitine palmitoyltransferase 2. Furthermore, the apolipoprotein B100 expression and microsomal triglyceride transfer protein activity were significantly decreased. SREBP-1c overexpression reduced lipid oxidation and VLDL synthesis, thereby decreasing TG disposal and export. Therefore, large amounts of TG accumulated in the bovine hepatocytes. Taken together, these results indicate that SREBP-1c overexpression increases lipid synthesis and decreases lipid oxidation and VLDL export, thereby inducing TG accumulation in bovine hepatocytes.
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The morbidity and survival of 196 consecutive cases undergoing liver transplantation in a single center in Mainland China: ten-year experience.
Ann. Transplant.
PUBLISHED: 01-14-2014
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Right lobar living donor living transplantation (LDLT) has been controversial because of widely differing reports of recipient morbidity. Herein, we present our nearly 10-year experience and identify factors that potentially could be modified to improve recipient outcome.
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Synthesis of renewable high-density fuels using cyclopentanone derived from lignocellulose.
Chem. Commun. (Camb.)
PUBLISHED: 01-10-2014
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By the combination of solvent-free aldol condensation and one-step hydrodeoxygenation under mild reaction conditions, a high-density (0.866 g mL(-1)) bicyclic C10 hydrocarbon was synthesized in high overall yield (up to 80%) using cyclopentanone derived from lignocellulose.
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Effect of piracetam on the cognitive performance of patients undergoing coronary bypass surgery: A meta-analysis.
Exp Ther Med
PUBLISHED: 01-08-2014
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Cognitive impairments are observed in numerous patients following coronary bypass surgery, and piracetam are nootropic compounds that modulate cerebral functions by directly enhancing cognitive processes. The present meta-analysis was conducted to evaluate the protective effect of piracetam on the cognitive performance of patients undergoing coronary bypass surgery. The relevant studies were identified by searching Medline, EMBASE, PubMed and the Cochrane Library up to June 2013 and the pertinent bibliographies from the retrieved studies were reviewed. Data were selected from the studies according to predefined criteria. The meta-analysis included two randomized control trials involving 184 patients and including the Syndrom-Kurz test (SKT). Findings of the meta-analysis showed that following treatment the change from baseline observed in five SKT subtest scores, conducted with piracetam patients, indicated a significant advantage over those patients that were in the placebo group. The subtests included immediate pictured object recall, weighted mean difference (WMD)=0.91, 95% confidence interval (CI) 0.51-1.31, P<0.00001; delayed pictured object recall, WMD=0.74, 95% CI 0.19-1.28, P=0.008; delayed picture recognition, WMD=0.82, 95% CI 0.31-1.31, P=0.001; immediate word recall, WMD=0.87, 95% CI 0.47-1.28, P<0.0001; and letter interference, WMD=3.46, 95% CI -5.69 to -1.23, P=0.002. These results indicated that piracetam may have been effective in improving the short-term cognitive performance of patients undergoing coronary bypass surgery. High quality, well-controlled and longer randomized trials are required to corroborate this result.
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Facile colorimetric method for simple and rapid detection of endotoxin based on counterion-mediated gold nanorods aggregation.
Biosens Bioelectron
PUBLISHED: 01-07-2014
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Existence of endotoxin in food and injection products indicates bacterial contaminations and therefore poses threat to human health. Herein, a simple and rapid colorimetric method for the effective detection of endotoxin in food and injections based on counterion-mediated gold nanorods aggregation is first proposed. By taking advantage of the color change of unmodified gold nanorods resulted from endotoxin mediated gold nanorods aggregation, endotoxin could be detected in the concentration range of 0.01-0.6 ?M. Further, we studied the performance of gold nanorods with different aspect ratios (2.7 and 3.3) in determination of endotoxin and found that gold nanorods with higher aspect ratio (AR) showed superiority in the sensing sensitivity of endotoxin. A good specificity for endotoxin, a detection limit of 0.0084 ?M and recoveries ranging from 84% to 109% in spiked food and injection samples are obtained with the colorimetric method. Results demonstrate that the present method provides a novel and effective approach for on-site screening of endotoxin in common products, which is beneficial for monitoring and reducing the risk of bacterial contaminations in food and injections production.
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Toxicity of copper oxide nanoparticles in the blue mussel, Mytilus edulis: a redox proteomic investigation.
Chemosphere
PUBLISHED: 01-05-2014
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Relatively little is known about the fate and effects of nanomaterials even in relatively simple organisms such as Mytilus edulis. Here, copper oxide nanoparticles (CuO NP) are shown to induce dose-dependent toxic effects at the biochemical, physiological and tissue levels in the blue mussel. Stable CuO NP suspensions were sized by differential light scattering and nanoparticle tracking analysis to yield average particle diameters of approximately 100 nm. These were administered to M. edulis, at doses of 400, 700 and 1000 ppb. Ingested copper was predominantly located in the gill tissue with small amounts in digestive gland. Fifteen coomassie-stained spots were excised from two dimensional gel electrophoresis separations of gill tissue extacts and identified by peptide mass fingerprinting. These contained six unique proteins (alpha- and beta-tubulin, actin, tropomyosin, triosephosphate isomerase and Cu-Zn superoxide dismutase). Of these, two spots (actin and triosephosphate isomerase) showed decreased protein thiols while three (alpha-tubulin, tropomyosin and Cu-Zn superoxide dismutase) showed increased carbonylation which is indicative of protein oxidation of cytoskeleton and enzymes in response to CuO NP. The neutral red retention time (NRRT) assay revealed toxicity due to the CuO NPs which was comparable with toxic metal oxide nanoparticles such as chromium and cobalt. In contrast, non-toxic titanium and gold metal oxide nanoparticles gave no NRRT effects at similar NP concentrations. Histology revealed deposition of pigmented brown cells in response to CuO NP, located predominantly along the mantle and gill margin but also lining digestive tubules and some of the sinuses and distributed throughout the connective tissue and in the adductor muscle.
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A Disordered Region in the EvpP Protein from the Type VI Secretion System of Edwardsiella tarda is Essential for EvpC Binding.
PLoS ONE
PUBLISHED: 01-01-2014
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The type VI secretion system (T6SS) of pathogenic bacteria plays important roles in both virulence and inter-bacterial competitions. The effectors of T6SS are presumed to be transported either by attaching to the tip protein or by interacting with HcpI (haemolysin corregulated protein 1). In Edwardsiella tarda PPD130/91, the T6SS secreted protein EvpP (E. tarda virulent protein P) is found to be essential for virulence and directly interacts with EvpC (Hcp-like), suggesting that it could be a potential effector. Using limited protease digestion, nuclear magnetic resonance heteronuclear Nuclear Overhauser Effects, and hydrogen-deuterium exchange mass spectrometry, we confirmed that the dimeric EvpP (40 kDa) contains a substantial proportion (40%) of disordered regions but still maintains an ordered and folded core domain. We show that an N-terminal, 10-kDa, protease-resistant fragment in EvpP connects to a shorter, 4-kDa protease-resistant fragment through a highly flexible region, which is followed by another disordered region at the C-terminus. Within this C-terminal disordered region, residues Pro143 to Ile168 are essential for its interaction with EvpC. Unlike the highly unfolded T3SS effector, which has a lower molecular weight and is maintained in an unfolded conformation with a dedicated chaperone, the T6SS effector seems to be relatively larger, folded but partially disordered and uses HcpI as a chaperone.
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Male breast carcinoma: a clinicopathological and immunohistochemical characterization study.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Male breast carcinoma is a relatively rare disease. This study retrospectively investigated the clinicopathological features of 73 cases of male breast carcinoma in Chinese population, and classified the molecular subtype based on surrogate immunohistochemical definitions. The expression of GCDFP15, MGB, AR and FOXP1 were evaluated. Invasive carcinoma of no special type was the most common histological type in the study group (71.2%, 52/73). The luminal A and B subtypes were the major types of male breast carcinoma (60.9%, 34.8% respectively). AR and FOXP1 are expressed in 84.2% (48/57) and 71.9% (41/57) of the studied cases. Carcinoma of the luminal A subtype expressed GCDFP15 (73.5%, 25/34) and MGB (58.8%, 20/34) more frequently than cases of the luminal B subtypes (34.8%, 8/23 and 43.5%, 10/23, respectively; P = 0.004, P = 0.255, respectively). In conclusion, invasive carcinoma of no special type was the most common histological type in male breast carcinoma among Chinese population. Our study revealed that the luminal A and B subtypes were the major types of male breast carcinoma. AR and FOXP1 are highly expressed in male breast cancer. The luminal A subtype tends to express GCDFP15 and MGB more frequently than the luminal B subtype.
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The rice enhancer of zeste [E(z)] genes SDG711 and SDG718 are respectively involved in long day and short day signaling to mediate the accurate photoperiod control of flowering time.
Front Plant Sci
PUBLISHED: 01-01-2014
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Recent advances in rice flowering studies have shown that the accurate control of flowering by photoperiod is regulated by key mechanisms that involve the regulation of flowering genes including Heading date1 (Hd1), Early hd1 (Ehd1), Hd3a, and RFT1. The chromatin mechanism involved in the regulation of rice flowering genes is presently not well known. Here we show that the rice enhancer of zeste [E(z)] genes SDG711 and SDG718, which encode the polycomb repressive complex2 (PRC2) key subunit that is required for trimethylation of histone H3 lysine 27 (H3K27me3), are respectively, involved in long day (LD) and short day (SD) regulation of key flowering genes. The expression of SDG711 and SDG718 is induced by LD and SD, respectively. Over-expression and down-regulation of SDG711 respectively, repressed and promoted flowering in LD, but had no effect in SD. By contrast, down-regulation of SDG718 had no effect in LD but delayed flowering in SD. SDG711 and SDG718 repressed OsLF (a repressor of Hd1) respectively in LD and SD, leading to a higher expression of Hd1 thus late flowering in LD and early flowering in SD. SDG711 was also found to be involved in the repression of Ehd1 in LD. SDG711 was shown to directly target to OsLF and Ehd1 loci to mediate H3K27me3 and gene repression. The function of the rice E(z) genes in LD repression and SD promotion of flowering suggests that PRC2-mediated epigenetic repression of gene expression is involved in the accurate photoperiod control of rice flowering.
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Radial growth of two dominant montane conifer tree species in response to climate change in north-central china.
PLoS ONE
PUBLISHED: 01-01-2014
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North-Central China is a region in which the air temperature has clearly increased for several decades. Picea meyeri and Larix principis-rupprechtii are the most dominant co-occurring tree species within the cold coniferous forest belt ranging vertically from 1800 m to 2800 m a.s.l. in this region. Based on a tree-ring analysis of 292 increment cores sampled from 146 trees at different elevations, this study aimed to examine if the radial growth of the two species in response to climate is similar, whether the responses are consistent along altitudinal gradients and which species might be favored in the future driven by the changing climate. The results indicated the following: (1) The two species grew in different rhythms at low and high elevation respectively; (2) Both species displayed inconsistent relationships between radial growth and climate data along altitudinal gradients. The correlation between radial growth and the monthly mean temperature in the spring or summer changed from negative at low elevation into positive at high elevation, whereas those between the radial growth and the total monthly precipitation displayed a change from positive into negative along the elevation gradient. These indicate the different influences of the horizontal climate and vertical mountainous climate on the radial growth of the two species; (3) The species-dependent different response to climate in radial growth appeared mainly in autumn of the previous year. The radial growth of L. principis-rupprechtii displayed negative responses both to temperature and to precipitation in the previous September, October or November, which was not observed in the radial growth of P. meyeri. (4) The radial growth of both species will tend to be increased at high elevation and limited at low elevation, and L. principis-rupprechtii might be more favored in the future, if the temperature keeps rising.
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Carcinoma arising in microglandular adenosis of the breast: triple negative phenotype with variable morphology.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Carcinoma arising in microglandular adenosis (MGACA) is an extremely rare subtype of breast carcinoma. In this study, clinicopathological analysis of MGACA from 11 Chinese patients was conducted. Microscopically, all cases showed a spectrum of structure and glandular proliferations ranging from microglandular adenosis (MGA) to atypical MGA (AMGA) to MGACA. Carcinoma components were composed of high grade ductal carcinoma in situ (DCIS) in 1 case and invasive carcinoma in 10 cases. Invasive carcinomas were grade 3 in 10 tumors and grade 2 in 1. Invasive components in 5 of 10 cases were composed of invasive carcinoma of no special type (NST), and 1 case showed partially acinic cell differentiation. In 5 cases, invasive components were mixed of NST and matrix-producing carcinoma (MPC). All epitheliums in 11 cases were triple negative (ER-, PR-, HER2-), and diffuse positive for CK and S-100 protein. No myoepithelial cells were demonstrable from MGA to invasive components with immunohistochemical staining for P63 and calponin. PAS or reticulin stain showed the presence of a basement membrane around glands in MGA, AMGA, DCIS, and its absence in invasive components. Follow-up time ranged from 10 to 64 months. One patient developed a lung metastasis 24 months after surgery, 10 patients have been alive without recurrence. Our study revealed that MGACA is a distinct subset of breast carcinoma, with triple negative phenotype, high grade nuclear and variable morphology. Despite histopathologic and immunohistochemical features usually associated with a poor prognosis, MGACA seems to have a relatively favorable outcome.
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Comparing outcomes of two vascular inflow occlusion techniques and treatment without vascular occlusion during major hepatectomy in patients with Hepatitis B-related hepatocellular carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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Significant hemorrhage together with blood transfusion has negative impact on postoperative morbidity, mortality, and long-term survival of liver resection. Various techniques of vascular occlusion have been developed to reduce intraoperative blood loss. The objective of this study was to compare the outcomes of Pringle maneuver, hemi-hepatic vascular occlusion, and treatment without vascular occlusion used during liver resection.
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Primary squamous cell carcinoma of the breast with unusual basal-HER2 phenotype.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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To report three cases of primary squamous cell carcinoma of the breast with an unusual "basal-HER2" phenotype.
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Direct removal of aqueous As(III) and As(V) by amorphous titanium dioxide nanotube arrays.
Environ Technol
PUBLISHED: 12-20-2013
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Amorphous titanium dioxide nanotube arrays (TiO2 NTs) were prepared by a simple anodization process without subsequent calcination at high temperature, and the effectiveness of amorphous TiO2 NTs as adsorbents in removing arsenite (As(III)) and arsenate (As(V)) was investigated. The TiO2 NTs were not only effective for arsenic removal without a pre-oxidation of As(III) to As(V) and/or adjusting the pH value of water before the adsorption process, but also can be separated and recovered easily from the solution. The adsorption kinetics and adsorption capacity of the amorphous TiO2 NTs for As(III) and As(V) were studied separately by batch experiments. The apparent values for Langmuir monolayer sorption capacities were 28.9 mg/g for As(III) and 24.7 mg/g for As(V) at pH 7. Kinetics studies indicated that the adsorption process on TiO2 NTs followed a pseudo-second-order kinetics model. Arsenic adsorption of TiO2 NTs remains stable over a broad pH range. Moreover, the TiO2 NTs have excellent stability and regeneration, and they can be used repeatedly at least five times.
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A high sensitivity MEA probe for measuring real time rat brain glucose flux.
Biosens Bioelectron
PUBLISHED: 08-29-2013
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The mammalian central nervous system (CNS) relies on a constant supply of external glucose for its undisturbed operation. This article presents an implantable Multi-Electrode Array (MEA) probe for brain glucose measurement. The MEA was implemented on Silicon-On-Insulator (SOI) wafer using Micro-Electro-Mechanical-Systems (MEMS) methods. There were 16 platinum recording sites on the probe and enzyme glucose oxidase (GOx) was immobilized on them. The glucose sensitivity of the MEA probe was as high as 489µAmM(-1)cm(-2). 1,3-Phenylenediamine (mPD) was electropolymerized onto the Pt recording surfaces to prevent larger molecules such as ascorbic acid (AA), 3,4-dihydroxyphenylacetic acid (DOPAC), serotonin (5-HT), and dopamine (DA) from reaching the recording sites surface. The MEA probe was implanted in the anesthetized rat striatum and responded to glucose levels which were altered by intraperitoneal injection of glucose and insulin. After the in vivo experiment, the MEA probe still kept sensitivity to glucose, these suggested that the MEA probe was reliable for glucose monitoring in brain extracellular fluid (ECF).
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Distribution of atmospheric particulate matter (PM) in rural field, rural village and urban areas of northern China.
Environ. Pollut.
PUBLISHED: 08-17-2013
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Atmospheric PM10 were measured for 12 months at 18 sites along a 2500 km profile across northern China. Annual mean PM10 concentrations in urban, rural village, and rural field sites were 180 ± 171, 182 ± 154, and 128 ± 89 ?g/m(3), respectively. The similarities in PM10 concentrations between urban and rural village sites suggest that strong localized emissions and severe contamination in rural residential areas are derived from solid fuels combustion in households. High PM10 concentrations in Wuwei and Taiyuan were caused by either sandstorms or industrial activities. Relatively low PM10 concentrations were observed in coastal areas of Dalian and Yantai. Particulate air pollution was much higher in winter and spring than in summer and fall. Multiple regression analysis indicates that 35% of the total variance can be attributed to sandstorms, precipitation and residential energy consumption. Over 40% of the measurements in both urban and rural village areas exceeded the national ambient air quality standard.
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Acoustic emission source location using a distributed feedback fiber laser rosette.
Sensors (Basel)
PUBLISHED: 08-16-2013
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This paper proposes an approach for acoustic emission (AE) source localization in a large marble stone using distributed feedback (DFB) fiber lasers. The aim of this study is to detect damage in structures such as those found in civil applications. The directional sensitivity of DFB fiber laser is investigated by calculating location coefficient using a method of digital signal analysis. In this, autocorrelation is used to extract the location coefficient from the periodic AE signal and wavelet packet energy is calculated to get the location coefficient of a burst AE source. Normalization is processed to eliminate the influence of distance and intensity of AE source. Then a new location algorithm based on the location coefficient is presented and tested to determine the location of AE source using a Delta (?) DFB fiber laser rosette configuration. The advantage of the proposed algorithm over the traditional methods based on fiber Bragg Grating (FBG) include the capability of: having higher strain resolution for AE detection and taking into account two different types of AE source for location.
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Spatial second-order interference of pseudothermal light in a Hong-Ou-Mandel interferometer.
Opt Express
PUBLISHED: 08-14-2013
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The spatial second-order interference of two independent pseudothermal light beams in a Hong-Ou-Mandel interferometer is studied experimentally and theoretically. The similar cosine modulation in the second-order coherence function as the one with entangled-photon pairs in a Hong-Ou-Mandel interferometer is observed. Two-photon interference based on Feynmans path integral theory is employed to interpret the results. The experimental results and theoretical simulations agree with each other very well.
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Comparison of Laparoscopy-Assisted and Open Donor Right Hepatectomy: a Prospective Case-Matched Study from China.
J. Gastrointest. Surg.
PUBLISHED: 08-13-2013
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Laparoscopy-assisted hepatectomy is a new minimally invasive approach for graft harvesting in living donors. Only a few liver transplant centers have introduced this surgical procedure.
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A comprehensive study of the safety of using anti-hepatitis B core (Hbc) positive subjects in living donor liver transplants.
Hepatogastroenterology
PUBLISHED: 08-13-2013
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In recent years, only few reports have addressed the safety of using living donors with a positive anti-Hepatitis B Core (HBc) antibody for liver transplants. Most reports have focused on short-term complications, short-term changes in liver function and regeneration of remnant liver. Long term follow-up data, quality of life and overall laboratory tests variations have not been appropriately studied. In our study, we aim to comprehensively investigate the safety of using anti-HBc-positive subjects in living donor liver transplants (LDLT).
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Systematic review of the safety of living liver donors.
Hepatogastroenterology
PUBLISHED: 08-09-2013
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Since the first living liver transplantation, the procedure has become routine with an excellent outcome and the shortage of organs for recipients has generated enthusiasm for living donor liver transplantation. One of the major challenges is the safety of the donor after donation. Here, we try to evaluate the overall safety of living donors.
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Assessment of tear film stability in dry eye with a newly developed keratograph.
Cornea
PUBLISHED: 08-08-2013
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To investigate the applicability of a newly developed corneal topographer in assessing tear film stability.
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[Experimental study of tissue engineered cartilage construction using oriented scaffold combined with bone marrow mesenchymal stem cells in vivo].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 07-25-2013
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To investigate the feasibility of fabricating an oriented scaffold combined with chondrogenic-induced bone marrow mesenchymal stem cells (BMSCs) for enhancement of the biomechanical property of tissue engineered cartilage in vivo.
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Coassembly of poly(ethylene glycol)-block-poly(glutamate sodium) and gemini surfactants with different spacer lengths.
Langmuir
PUBLISHED: 07-18-2013
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The coassembly of poly(ethylene glycol)-b-poly(glutamate sodium) copolymer (PEG113-PGlu100) with cationic gemini surfactants alkanediyl-?,?-bis-(dodecyldimethylammonium bromide) [C12H25(CH3)2N(CH2)SN(CH3)2C12H25]Br2 (designated as C12CSC12Br2, S = 3, 6, and 12) have been studied by isothermal titration microcalorimetry, cryogenic transmission electron microscopy, circular dichroism, small-angle X-ray scattering, zeta potential, and size measurement. It has been shown that the electrostatic interaction of C12CSC12Br2 with the anionic carboxylate groups of PEG113-PGlu100 leads to complexation, and the C12CSC12Br2/PEG113-PGlu100 complexes are soluble even at the electroneutral point. The complexes display the feature of superamphiphiles and assemble into ordered nanosheets with a sandwich-like packing. The gemini molecules which were already bound with PGlu chains associate through hydrophobic interaction and constitute the middle part of the nanosheets, whereas the top and bottom of the nanosheets are hydrophilic PEG chains. The size and morphology of the nanosheets are affected by the spacer length of the gemini surfactants. The average sizes of the aggregates at the electroneutral point are 81, 68, and 90 nm for C12C3C12Br2/PEG113-PGlu100, C12C6C12Br2/PEG113-PGlu100, and C12C12C12Br2/PEG113-PGlu100, respectively. Both C12C3C12Br2/PEG113-PGlu100 and C12C12C12Br2/PEG113-PGlu100 mainly generate hexagonal nanosheets, while the C12C6C12Br2/PEG113-PGlu100 system only induces round nanosheets.
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Comparative analysis of receptor-binding specificity and pathogenicity in natural reassortant and non-reassortant H3N2 swine influenza virus.
Vet. Microbiol.
PUBLISHED: 07-03-2013
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Genetic reassortment between human and avian influenza viruses can create pandemic viruses. Influenza surveillance of pigs in Jilin Province, in China during 2007-2008 revealed that there were two distinguishable genotypes: a human-like H3N2 genotype and a double-reassortant genotype derived from the human H3N2 and avian H5 viruses. In this study, viral infection potential, replication kinetics, and pathogenicity were compared. The solid-phase binding assay demonstrated that both viruses prominently maintained a preference for the human-type receptor and the reassortant A/swine/Jilin/37/2008 (Sw/JL/37/08) showed relatively higher binding affinities than the non-reassortant A/swine/Jilin/19/2007 (Sw/JL/19/07). Replication kinetics showed that Sw/JL/37/08 had higher replicability in MDCK cells than Sw/JL/19/07. The mouse experiments clearly revealed that Sw/JL/37/08 had higher virulence than Sw/JL/19/07 as measured by more significant body weight loss, higher viral lung load, delayed viral clearance from lungs, and more severe pulmonary lesions. Sequence analysis indicated that the absence of glycosylation sites at residue 126 of HA and 93 of NA, as well as the characteristic NS1 C-terminal PL residues of ESEV may account for the increased replication and pathogenicity of Sw/JL/37/08. These results may imply that human may have infection risk by the reassortant swine influenza virus and emphasize the necessity for enhanced viral surveillance strategies, which monitor reassortment events in nature to reduce the public health threat posed by influenza viruses with the potential for human-to-human transmission currently circulating in pig populations.
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Gene-environment and protein-degradation signatures characterize genomic and phenotypic diversity in wild Caenorhabditis elegans populations.
BMC Biol.
PUBLISHED: 07-03-2013
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Analyzing and understanding the relationship between genotypes and phenotypes is at the heart of genetics. Research on the nematode Caenorhabditis elegans has been instrumental for unraveling genotype-phenotype relations, and has important implications for understanding the biology of mammals, but almost all studies, including forward and reverse genetic screens, are limited by investigations in only one canonical genotype. This hampers the detection and functional analysis of allelic variants, which play a key role in controlling many complex traits. It is therefore essential to explore the full potential of the natural genetic variation and evolutionary context of the genotype-phenotype map in wild C. elegans populations.
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Fate modeling of mercury species and fluxes estimation in an urban river.
Environ. Pollut.
PUBLISHED: 06-11-2013
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The fate and transfer of mercury in urban river is an important environmental concern. In this study, QWASI (Quantitative Water-Air-Sediment Interaction) model was selected to estimate the levels of total mercury and three mercury species in water and sediment, and was used to quantify the fluxes of mercury at water/air and sediment/water interfaces of an urban river. The predicted mercury levels in water and sediments were closed to the measured values. Water inflow, re-suspension of sediment and diffusion from sediment to water are major input sources of mercury in water. The net mercury transfer flux from water to air was 0.16 ng/(m(2) h). At the sediment/water interface, a net total mercury transfer of 1.32 ng/(m(2) h) from water to sediment was seen. In addition to the existing dynamic flux chambers measurement, this model method could provide a new perspective to identify the distribution and transfer of mercury in the urban river.
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Cationic gemini surfactant-assisted synthesis of hollow Au nanostructures by stepwise reductions.
ACS Appl Mater Interfaces
PUBLISHED: 06-11-2013
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A novel synthetic approach was developed for creating versatile hollow Au nanostructures by stepwise reductions of Au(III) upon the use of cationic gemini surfactant hexamethylene-1,6-bis(dodecyl dimethylammonium bromide) (C12C6C12Br2) as a template agent. It was observed that the Au(I) ions obtained from the reduction of Au(III) by ascorbic acid can assist the gemini surfactant to form vesicles, capsule-like, and tube-like aggregates that subsequently act as soft templates for hollow Au nanostructures upon further reduction of Au(I) to Au(0) by NaBH4. It was demonstrated that the combination of C12C6C12Br2 and Au(I) plays a key role in regulating the structure of the hollow precursors not only because C12C6C12Br2 has a stronger aggregation ability in comparison with its single chain counterpart but also because the electrostatic repulsion between head groups of C12C6C12Br2 is greatly weakened after Au(III) is converted to Au(I), which is in favor of the construction of vesicles, capsule-like, and tube-like aggregates. Compared with solid Au nanospheres, the resultant hollow nanostructures exhibit enhanced electrocatalytic activities in methanol oxidation, following the order of elongated nanocapsule > nanocapsule > nanosphere. Benefiting from balanced interactions between the gemini surfactant and Au(I), this soft-template method may present a facile and versatile approach for the controlled synthesis of Au nanostructures potentially useful for fuel cells and other Au nanodevices.
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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.