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Find video protocols related to scientific articles indexed in Pubmed.
Synthesis, crystal structures and two-photon absorption properties of triphenylamine cyanoacetic acid derivative and its organooxotin complexes.
Dalton Trans
PUBLISHED: 11-12-2014
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Three novel organooxotin complexes (, and ) were synthesized by reaction of (2-cyano-3-(4-(diphenylamino)phenyl) acrylic acid) with n-Bu2SnO, Ph3Sn(OH) and nBu6Sn2O. The structures of the three complexes have been confirmed by single-crystal X-ray diffraction analysis. The metal complex features a ladder framework while and show discrete structures. The UV-vis absorption, single-photon excited fluorescence (SPEF) and two-photon excited fluorescence (2PEF) of the complexes have been systematically studied, suggesting that the three metal complexes have strong two-photon absorption (2PA) and large 2PA cross-sections. It is noteworthy that possesses an enhanced two-photon absorption, and exhibits larger 2PA cross-section per molecular weight compared to . Finally, high anti-tumor activity of these three metal complexes has also been identified.
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Interconversion between Three Overstretched DNA Structures.
J. Am. Chem. Soc.
PUBLISHED: 11-04-2014
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Double-stranded DNA can exist in multiple structures, including three recently identified overstretched structures (peeled ssDNA, DNA bubble, and S-DNA) for torsion-unconstrained DNA under large tension. Here, we report systematic studies of interconversion between these overstretched DNA structures induced by changing NaCl concentration at constant force. At forces above 70 pN where DNA exists in one of the overstretched states, direct interconversions between S-DNA and DNA bubble for the end-closed DNA construct, as well as interconversions between S-DNA and peeled ssDNA for the end-opened DNA construct, were observed to involve stepwise extension changes. Interestingly, compared to other conversions, the conversion from peeled ssDNA to S-DNA has ultraslow kinetics, which can be explained by formation of secondary hairpin structures on a relaxed strand of peeled ssDNA. Our findings provide important insights into the structures of torsion-unconstrained DNA under large force.
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Effect of genotype and environment on five bioactive components of cultivated licorice (Glycyrrhiza uralensis FISCH.) populations in northern China.
Biol. Pharm. Bull.
PUBLISHED: 10-31-2014
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Methods to improve the bioactive component content of cultivated licorice have become the bottleneck of industrial licorice extraction for pharmaceutical use. To evaluate the effects of genotype, environment and their interaction on major bioactive components, we analyzed the five bioactive components: liquiritin (LQ), liquiritigenin (LQG), glycyrrhizin (GL), isoliquiritin (ILQ) and isoliquiritigenin (ILQG) of four diverse licorice varieties grown in four distinct environments in northern China during 2010-11. Analysis of variance showed that environmental and genotypic effects were significant (P<0.01) for all five bioactive components. Additionally, their interaction was significant (P<0.05) for GL in the 2-year study period. LQ and ILQ were mainly affected by genetic factors and have great potential for genetic improvement, whereas LQG and ILQG were mainly affected by environmental factors. GL was similarly affected by environmental and genetic factors. Biplot of the principal component analysis showed that for quality breeding, G2 (WNT-1) and G3 (JX-1) are two relatively preferable genotypes, and E2 (Chifeng) location is suitable for accumulation of the bioactive components of these two genotypes. Stepwise regression analysis showed that sunshine and rainfall are the dominant environmental factors for licorice bioactive component accumulation; increased duration of sunshine is advantageous to GL accumulation whereas declining rainfall is conducive to LQG and ILQG accumulation. These results provide a theoretical basis for initiating licorice breeding programs with increased bioactive components and improved quality.
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Magnetic field sensing based on magnetic-fluid-clad fiber-optic structure with taper-like and lateral-offset fusion splicing.
Opt Express
PUBLISHED: 10-17-2014
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A kind of magnetic field sensor composed of magnetic fluid surrounding a segment of singlemode fiber is proposed. The taper-like and lateral-offset fusion splicing techniques are employed. The sensing principle is based on cladding mode interference. The interference valley wavelength or transmission loss of the sensing structure is sensitive to the external magnetic field, which is utilized for magnetic field sensing. The linear response regions are obtained in the range of 38-225 Oe and 250-475 Oe. For the valley-wavelength-shift-type sensing, the sensitivities are 14.1 pm/Oe and 26 pm/Oe at low and high field ranges, respectively. For the transmission-loss-variation-type sensing, the sensitivity of -0.024 dB/Oe is achieved for the magnetic field strength ranging from 250 to 475 Oe.
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Development of T Cells Redirected to Glypican-3 for the Treatment of Hepatocellular Carcinoma.
Clin. Cancer Res.
PUBLISHED: 10-17-2014
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Purpose:The aim of our study is to elucidate whether T cells expressing GPC3-targeted chimeric antigen receptor (CAR) can efficiently eliminate GPC3-positive HCC cells and their potential in the treatment of HCC. Experimental Design:T cells expressing a first generation and third generation GPC3-targeted CAR were prepared using lentiviral vector transduction. The in vitro and in vivo cytotoxic activities of the genetically engineered CAR T cells were evaluated against various HCC cell lines. Results:GPC3-targeted CAR T cells could efficiently kill GPC3-positive HCC cells but not GPC3-negative cells in vitro. These cytotoxic activities appeared to be positively correlated with GPC3 expression levels in the target cells. Additionally, T cells expressing the third generation GPC3-targeted CAR could eradicate HCC xenografts with high level of GPC3 expression and efficiently suppress the growth of HCC xenografts with low GPC3 expression level in vivo. The survival of the mice bearing established orthotopic Huh-7 xenografts was significantly prolonged by the treatment with the third generation GPC3-targeted CAR T cells. Conclusions:GPC3-targeted CAR T cells could potently eliminate GPC3-positive HCC cells, thereby providing a promising therapeutic intervention for GPC3-positive HCC.
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Development of New P-Chiral P,?-Dihydrobenzooxaphosphole Hybrid Ligands for Asymmetric Catalysis.
Org. Lett.
PUBLISHED: 10-09-2014
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A new family of P-chiral P,?-hybrid ligands was prepared from the dihydrobenzooxaphosphole core. These new ligands were demonstrated to be both sterically and electronically tunable at the substituents on the phosphorus atom and the ?-system of the ligand. Application of these new ligands to the catalytic asymmetric addition of boronic acids to imine electrophiles was shown to proceed with high levels of enantioinduction.
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Automatic staging of placental maturity based on dense descriptor.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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Currently, placental maturity staging is mainly based on subjective observation of the physician. To address this issue, a new method is proposed for automatic staging of placental maturity based on B-mode ultrasound images. Due to small variations in the placental images, dense descriptor is utilized in place of the sparse descriptor to boost performance. Dense sampled DAISY descriptor is investigated for the demonstrated scale and translation invariant properties. Moreover, the extracted dense features are encoded by vector locally aggregated descriptor (VLAD) for performance boosting. The experimental results demonstrate an accuracy of 0.874, a sensitivity of 0.996 and a specificity of 0.874 for placental maturity staging. The experimental results also show that the dense features outperform the sparse features.
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A Mild Dihydrobenzooxaphosphole Oxazoline/Iridium Catalytic System for Asymmetric Hydrogenation of Unfunctionalized Dialins.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 09-09-2014
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Air-stable P-chiral dihydrobenzooxaphosphole oxazoline ligands were designed and synthesized. When they were used in the iridium-catalyzed asymmetric hydrogenation of unfunctionalized 1-aryl-3,4-dihydronaphthalenes under one atmosphere pressure of H2 , up to 99:1 e.r. was obtained. High enantioselectivities were also observed in the reduction of the exocyclic imine derivatives of 1-tetralones.
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[Single-port video-assisted thoracoscopic surgery for pulmonary diseases: analysis of 158 cases].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 09-02-2014
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To assess the clinical value of single-port video-assisted thoracoscopic surgery (VATS) for treatment of pulmonary diseases.
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[An approach to screen fetal agenesis of the corpus callosum at 11-13(+6) weeks].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 09-02-2014
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To detect structural changes in the brain in fetuses with agenesis of the corpus callosum (ACC) and holoprosencephaly (HPE) in the first trimester.
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Addressing the configuration stability of lithiated secondary benzylic carbamates for the development of a noncryogenic stereospecific boronate rearrangement.
Org. Lett.
PUBLISHED: 08-25-2014
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A practical noncryogenic process for the Aggarwal stereospecific boronate rearrangement with chiral secondary benzylic carbamates has been developed. The use of LDA instead of sec-BuLi combined with an in situ trapping of the unstable lithiated carbamate was critical to success. Furthermore, this new process increased the substrate scope to include the versatile aryl iodide and bromide substrates. The methodology was applied to a diverse array of substrates and was demonstrated on multikilogram scale.
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Copy number variations of GATA4 and NKX2-5 in Chinese fetuses with congenital heart disease.
Pediatr Int
PUBLISHED: 08-22-2014
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Congenital heart disease (CHD) is one of the most common birth defects in newborns. The etiology of CHD has remained largely unknown, but it is assumed to result from the combined effects of genetic and environmental factors. Recent investigations have detected potentially pathogenic copy number variations (CNVs) in a proportion of patients with CHD. The present case-control study aimed at evaluating whether CNVs in the GATA4 and NKX2-5 genes contribute to the pathogenesis of CHD in Chinese fetuses (n = 117), by comparing the results to non-CHD control subjects (n = 100).
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Efficient Encapsulation of Fe3 O4 Nanoparticles into Genetically Engineered Hepatitis B Core Virus-Like Particles Through a Specific Interaction for Potential Bioapplications.
Small
PUBLISHED: 08-22-2014
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Self-assembly of viral coating proteins encapsulating functional nanoparticles provides a new class of biomaterials with robust chemical and physical properties for potential applications in functional imaging, and therapeutic or diagnostic agent delivery. Herein, a straightforward method is demonstrated for efficient encapsidation of magnetic nanoparticles into the engineered virus-like particle (VLP) through the affinity of histidine tags for the nickel- nitrilotriacetic acid (NTA) chelate. Monodispersed, uniformly sized, magnetic core-containing VLPs are obtained at high efficiency (>85%) and used as the cellular T2 contrast agents for MR imaging applications thanks to their biocompatibility, higher cellular uptake, as well as higher r2 values.
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Correlation between Congenital Heart Defects and maternal copper and zinc concentrations.
Birth Defects Res. Part A Clin. Mol. Teratol.
PUBLISHED: 08-18-2014
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The aim of this study was to investigate the correlation between maternal concentrations of copper and zinc and the risk of having an infant with a congenital heart defect (CHD).
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Insights into chromatographic enantiomeric separation of allenes on cellulose carbamate stationary phase.
J Chromatogr A
PUBLISHED: 08-16-2014
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Allenes are cumulenes with three contiguous carbons linked together through double bonds. 1,3-disubstituted allenes are not superimposable on their mirror image; as a consequence they are chiral. Chiral allenes are increasingly important in organic synthesis due to their interesting reactivity. Because of their applications in the field of asymmetric catalysis and in the pharmaceutical industry their optical purity is always a parameter which needs to be determined. In this article, we report the enantiomeric separation of hexa-3,4-diene-3-ylbenzene, an aromatic allene, on a cellulose carbamate (Chiralcel OD-3) stationary phase, using heptane as the mobile phase. Spectroscopic studies using infrared (IR) and vibrational circular dichroism revealed that, in the presence of heptane, the stationary phase undergoes a conformational change due to intermolecular H-bonding between the CO and NH of the neighboring polymer chains. Van't Hoff plots for the retention factor, k, showed that the retention of the two enantiomers is dominated by the enthalpy, while the plot for the selectivity, ?, is entropy driven. This suggests that the enantioselectivity is a result of inclusion of the enantiomers in the cavities of the chrial stationary phase. VCD spectra, along with density functional theory calculation (DFT) of the interaction between each enantiomer and the chiral stationary phase, supported the chromatographic elution order findings.
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The role of doppler waveforms in the fetal main pulmonary artery in the prediction of neonatal respiratory distress syndrome.
J Clin Ultrasound
PUBLISHED: 08-11-2014
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To describe changes in the Doppler waveforms of the fetal main pulmonary artery (MPA) throughout gestation and to assess their predictive value of neonatal respiratory distress syndrome (RDS).
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Facile entry to an efficient and practical enantioselective synthesis of a polycyclic cholesteryl ester transfer protein inhibitor.
Org. Lett.
PUBLISHED: 08-01-2014
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An efficient enantioselective synthesis of the chiral polycyclic cholesteryl ester transfer protein (CETP) inhibitor 1 has been developed. The synthesis was rendered practical for large scale via the development of a modified Hantzsch-type reaction to prepare the sterically hindered pyridine ring, enantioselective hydrogenation of hindered ketone 6 utilizing novel BIBOP-amino-pyridine derived Ru complex, efficient ICl promoted lactone formation, and a BF3 mediated hydrogenation process for diastereoselective lactol reduction. This efficient route was successfully scaled to produce multikilogram quantities of challenging CETP drug candidate 1.
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Synthesis, spectral and third-order nonlinear optical properties of terpyridine Zn(II) complexes based on carbazole derivative with polyether group.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 07-27-2014
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Four novel Zn(II) terpyridine complexes (ZnLCl2, ZnLBr2, ZnLI2, ZnL(SCN)2) based on carbazole derivative group were designed, synthesized and fully characterized. Their photophysical properties including absorption and one-photon excited fluorescence, two-photon absorption (TPA) and optical power limiting (OPL) were further investigated systematically and interpreted on the basis of theoretical calculations (TD-DFT). The influences of different solvents on the absorption and One-Photon Excited Fluorescence (OPEF) spectral behavior, quantum yields and the lifetime of the chromophores have been investigated in detail. The third-order nonlinear optical (NLO) properties were investigated by open/closed aperture Z-scan measurements using femtosecond pulse laser in the range from 680 to 1080 nm. These results revealed that ZnLCl2 and ZnLBr2 exhibited strong two-photon absorption and ZnLCl2 showed superior optical power limiting property.
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Effect of polymorphisms in the CSN3 (?-casein) gene on milk production traits in Chinese Holstein Cattle.
Mol. Biol. Rep.
PUBLISHED: 07-27-2014
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This study was designed to evaluate significant associations between single nucleotide polymorphisms (SNPs) and milk composition and milk production traits in Chinese Holstein cows. Six SNPs were identified in the ?-casein gene using pooled DNA sequencing. The identified SNPs were genotyped by Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) methods from 507 individuals. Out of six, we identified three non-synonymous SNPs (g.10888T>C, g.10924C>A and g.10944A>G) that changed in the protein product. SIFT (Sorting_Intolerant_From_Tolerant) prediction score (0.01) demonstrated that protein changed Isoleucine > Threonine (g.10888T>C) will affect the phenotypes. Significant associations between identified SNPs and three yield traits (milk, protein and fat) and two composition traits (fat and protein percentages) were found whereas it did not reach significance for fat percentage in haplotypes association. Importantly, the significant SNPs in our results showed a large proportion of the phenotypic variation of milk protein yield and concentration. Our results suggest that CSN3 is an important candidate gene that influences milk production traits, and identified polymorphisms and haplotypes could be used as a genetic marker in programs of marker-assisted selection for the genetic improvement of milk production traits in dairy cattle.
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Downregulation of microRNA miR-526a by enterovirus inhibits RIG-I-dependent innate immune response.
J. Virol.
PUBLISHED: 07-23-2014
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Retinoic acid-inducible gene I (RIG-I) is an intracellular RNA virus sensor that induces type I interferon-mediated host-protective innate immunity against viral infection. Although cylindromatosis (CYLD) has been shown to negatively regulate innate antiviral response by removing K-63-linked polyubiquitin from RIG-I, the regulation of its expression and the underlying regulatory mechanisms are still incompletely understood. Here we show that RIG-I activity is regulated by inhibition of CYLD expression mediated by the microRNA miR-526a. We found that viral infection specifically upregulates miR-526a expression in macrophages via interferon regulatory factor (IRF)-dependent mechanisms. In turn, miR-526a positively regulates virus-triggered type I interferon (IFN-I) production, thus suppressing viral replication, the underlying mechanism of which is the enhancement of RIG-I K63-linked ubiquitination by miR-526a via suppression of the expression of CYLD. Remarkably, virus-induced miR-526a upregulation and CYLD downregulation are blocked by enterovirus 71 (EV71) 3C protein, while ectopic miR-526a expression inhibits the replication of EV71 virus. The collective results of this study suggest a novel mechanism of the regulation of RIG-I activity during RNA virus infection by miR-526a and suggest a novel mechanism for the evasion of the innate immune response controlled by EV71.
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Magnetic field sensing based on magnetic-fluid-clad multimode-singlemode-multimode fiber structures.
Sensors (Basel)
PUBLISHED: 07-17-2014
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Magnetic field sensing based on magnetic-fluid-clad multimode-singlemode- multimode fiber structures is proposed and experimentalized. The structures are fabricated out using fiber fusion splicing techniques. The sensing principle is based on the interference between the core mode and cladding modes. Two interference dips are observed in our spectral range. Experimental results indicate that the magnetic field sensing sensitivities of 215 pm/mT and 0.5742 dB/mT are obtained for interference dip around 1595 nm. For interference dip around 1565 nm, the sensitivities are 60.5 pm/mT and 0.4821 dB/mT. The response of temperature is also investigated. The temperature sensitivity for the dip around 1595 nm is obtained to be 9.93 pm/°C.
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Genetic and component content differentiation between wild and cultivated populations of Paeonia lactiflora and related species used as Chishao and Baishao in China.
Biol. Pharm. Bull.
PUBLISHED: 07-09-2014
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One hundred and forty-four samples of Chishao and Baishao, which represented six species of Paeonia L. were evaluated for their genetic variation, genetic differentiation and phylogenetic relationship, based on the nuclear ribosomal DNA internal transcribed spacer (ITS) region. Samples from representative of the population were then used to do a cultivation comparison experiment, and then to identify the contents of the active ingredients. The results showed there were differences in the haplotype distribution and frequency between populations of Chishao and Baishao. An analysis of molecular variance (AMOVA) indicated statistically significant (p<0.001) genetic differentiation between the populations of wild and cultivated Paeonia lactiflora PALL. The albiflorin content between Chishao and Baishao was also significantly different (p<0.05). All the results clearly illustrate that currently cultivated P. lactiflora cannot be used as a substitute for Chishao.
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Iron-oxide nanoparticles embedded silica microsphere resonator exhibiting broadband all-optical wavelength tunability.
Opt Lett
PUBLISHED: 07-01-2014
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In this Letter, a novel silica microsphere resonator (MSR) embedded with iron-oxide nanoparticles, which possesses broadband all-optical wavelength tunability, is demonstrated. It is generated by using in-line 1550 nm laser ablation of a microfiber with the assistance of magnetic fluid. To the best of our knowledge, this simple method of fabricating such MSRs is reported for the first time. Prominent photothermal effect is realized by the iron-oxide nanoparticles absorbing light pumped via the fiber stem, leading to a wavelength shift of over 13 nm (1.6 THz). Moreover, a linear tuning efficiency up to 0.2??nm/mW is realized. With excellent robustness and being fiberized, the spheres can be attractive elements in building up novel micro-illuminators, point heaters, optical sensors, and fiber communication modules.
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Integrating analysis reveals microRNA-mediated pathway crosstalk among Crohn's disease, ulcerative colitis and colorectal cancer.
Mol Biosyst
PUBLISHED: 06-21-2014
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Inflammatory bowel disease (IBD), which can increase the risk of colorectal cancer (CRC), includes two primary subtypes, ulcerative colitis (UC) and Crohn's disease (CD). Although several individual genes involved in inflammation or cancer characterization have been identified, it is still difficult to elucidate functional relationship details between the molecules underlying pathogenesis at the system level. The global effect of miRNAs on genes or their involved functions is also poorly understood. We first integrated genome-wide gene expression profiles and biological pathway information to explore the underlying associations among UC, CD and CRC at the function and gene level. After identifying the pathways regulated by miRNAs, a global map of miRNA-mediated pathway crosstalk shared by the three diseases was further constructed to vertically explain the links of three level alterations. The three types of diseases have close associations with each other at the levels of function, gene and miRNA regulation. Several key biological pathways are involved in the three diseases, related to the immune system and inflammation, metabolism, or cell proliferation and apoptosis etc. Moreover, miRNAs exhibit dominant effects on multiple pathways. It is worth noting that UC shows relatively close associations with CD and CRC at the three levels. Finally, the miRNAs could mediate the crosstalk within or between pathways. For example, hsa-miR-125b, hsa-miR-335 and hsa-miR-155 mediated the crosstalk between three metabolic pathways. The crosstalk within the Toll-like receptor signaling pathway could be mediated by hsa-miR-124, hsa-miR-146a and hsa-mir-221/222. Our results make sense for the prevention and treatment of intestinal-related chronic inflammation or cancer.
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All-optical tuning of a magnetic-fluid-filled optofluidic ring resonator.
Lab Chip
PUBLISHED: 06-19-2014
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An all-optical tunable optofluidic ring resonator (OFRR) is proposed and experimentally demonstrated. The all-optical control of a silica microresonator is highly attractive, but it is difficult to realize because of the relatively weak Kerr effect and the absence of a plasma dispersion effect of silica. Here, we infuse a silica microcapillary-based optofluidic ring resonator with a magnetic fluid, into which pump light is injected by a fiber taper. Iron oxide nanoparticles dispersed in the magnetic fluid produce a strong pump light absorption, and this leads to a resonance shift of the silica microresonator due to the photothermal effect. To the best of our knowledge, this is the first scheme for all-optical tuning of an OFRR. A tuning sensitivity of up to 0.15 nm mW(-1) and a tuning range of 3.3 nm are achieved. With such excellent performance, the magnetic-fluid-filled OFRR has great potential in filtering, sensing, and signal processing applications.
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Remarkable Enhancement of Enantioselectivity in the Asymmetric Conjugate Addition of Dimethylzinc to (Z)-Nitroalkenes with a Catalytic [(MeCN)4 Cu]PF6 -Hoveyda Ligand Complex.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 06-15-2014
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An enantioselective copper-catalyzed asymmetric conjugate addition of Me2 Zn to (Z)-nitroalkenes led to the formation of all-carbon quaternary stereogenic centers with high stereoselectivity. The key features of the new method are the unprecedented use of [(MeCN)4 Cu]PF6 in conjunction with the Hoveyda ligand L1 and the use of (Z)-nitroalkene substrates so that undesired nitroalkene isomerization is minimized and enantioselectivity is enhanced dramatically. We also describe a novel, practical, and highly (Z)-selective nitroalkene synthesis.
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Risk Factors Associated with Prolonged Mechanical Ventilation after Corrective Surgery for Tetralogy of Fallot.
Congenit Heart Dis
PUBLISHED: 06-09-2014
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This study examined early postoperative results to identify perioperative factors that are associated with prolonged mechanical ventilation (PMV) in tetralogy of Fallot (TOF) patients undergoing corrective surgery.
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Comparative epigenetic analyses reveal distinct patterns of oncogenic pathways activation in breast cancer subtypes.
Hum. Mol. Genet.
PUBLISHED: 05-27-2014
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Breast cancer is a highly heterogeneous disease that is characterized by genetic and epigenetic aberrations; however, our knowledge of epigenetic alterations of breast cancer subtypes remains limited. Here, we portrayed and compared the alterations of six types of histone modifications and DNA methylation between two breast cancer subtypes, luminal and basal. Widespread subtype-specific epigenetic alterations were observed in both subtypes, which preferentially occurred within CpG islands (CGIs) and promoter regions. Specifically, aberrant DNA methylation was mostly located inside CGIs in luminal subtype, whereas in basal subtype it was principally located within CGI shores. Moreover, different types and combinatorial patterns of epigenetic alterations were found to occupy at promoter regions between these two subtypes. And these epigenetic alterations regulated corresponding gene expression in a synergetic way in both subtypes. Functional enrichment analysis highlighted that epigenetically dysregulated genes were significantly involved in the hallmarks of cancers, most of which were subtype specific. Even genes involved in the same hallmarks associated biological processes were affected by various types of epi-modifications in different subtypes. Finally, we revealed distinct patterns of oncogenic pathways activation in different subtypes and provided novel insights into subtype specific therapeutic opportunities. In addition, genes in the key signaling pathways were able to discriminate between disease phenotypes, and subtype-specific progression associated genes were identified. This study presents the aberrant epigenetic patterns of breast cancer subtypes at a genome-wide level, which will be a highly valuable resource for investigations at understanding epigenetic regulation of breast cancer subtypes.
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In vitro and in vivo evaluation of capsaicin-loaded microemulsion for enhanced oral bioavailability.
J. Sci. Food Agric.
PUBLISHED: 05-23-2014
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Capsaicin, as a food additive, has attracted worldwide concern owing to its pungency and multiple pharmacologic effects. However, poor water solubility and low bioavailability limited its application. This study aims to develop capsaicin-loaded microemulsion to enhance the oral bioavailability of the anti-neuropathic-pain component, capsaicin, which is poorly water soluble.
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Genome-wide association study for pigmentation traits in Chinese Holstein population.
Anim. Genet.
PUBLISHED: 05-13-2014
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With the Illumina BovineSNP50K BeadChip, we performed a genome-wide association study (GWAS) for two pigmentation traits in a Chinese Holstein population: proportion of black (PB) and teat colour (TC). A case-control design was used. Cases were the cows with PB <0.30 (n = 129) and TC <2 points (n = 140); controls were those with PB >0.90 (n = 58) and TC >4 points (n = 281). The RM test of roadtrips (version 1.2) was applied to detect SNPs for the two traits with 42 883 and 42 741 SNPs respectively. A total of nine and 12 genome-wide significant (P < 0.05) SNPs associated with PB and TC respectively were identified. Of these, two SNPs for PB were located within the KIT and IGFBP7 genes, and the other four SNPs were 23~212 kb away from the PDGFRA gene on BTA6; nine SNPs associated with TC were located within or 21~78.8 kb away from known genes on chromosomes 4, 11, 22, 23 and 24. By combing through our GWAS results and the biological functions of the genes, we suggest that the KIT, IGFBP7, PDGFRA, MITF, ING3 and WNT16 genes are promising candidates for PB and TC in Holstein cattle, providing a basis for further investigation on the genetic mechanism of pigmentation formation.
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General and rapid pyrimidine condensation by addressing the rate limiting aromatization.
Org. Lett.
PUBLISHED: 05-12-2014
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The rate limiting aromatization within the condensation approach toward pyrimidines utilizing amidines and activated olefins was addressed to provide for a general and rapid process. A strong solvent effect was elucidated to affect the rate for the initial alkoxide elimination from the intermediate Michael adduct wherein polar aprotic solvents demonstrate an addition controlled aromatization. Spectroscopic studies support a solvent dependent equilibrium between the amidine and alkoxide base wherein the rate for aromatization is optimal when the equilibrium toward the amidine anion was strongly favored.
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Seminal plasma protein in renal cell carcinoma: expression of semenogelin I is a predictor for cancer progression and prognosis.
Tumour Biol.
PUBLISHED: 04-29-2014
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The incidence of renal cell carcinoma (RCC) has been steadily rising each year. There are currently few recognized biomarkers for the diagnosis and prognosis of RCC. We investigated semenogelin I (Sg I) expression and its clinical significance in patients with RCC. The expression levels of Sg I and its protein were measured by qPCR and Western blotting, respectively. Immunohistochemistry was used to investigate the protein expression of Sg I in RCC and normal renal tissue from 53 patients. The Kaplan-Meier method and log-rank test were used to evaluate the data. By qRCR (p?
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Construction of a promoter collection for genes co-expression in filamentous fungus Trichoderma reesei.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 04-26-2014
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Trichoderma reesei is the preferred organism for producing industrial cellulases. However, cellulases derived from T. reesei have their highest activity at acidic pH. When the pH value increased above 7, the enzyme activities almost disappeared, thereby limiting the application of fungal cellulases under neutral or alkaline conditions. A lot of heterologous alkaline cellulases have been successfully expressed in T. reesei to improve its cellulolytic profile. To our knowledge, there are few reports describing the co-expression of two or more heterologous cellulases in T. reesei. We designed and constructed a promoter collection for gene expression and co-expression in T. reesei. Taking alkaline cellulase as a reporter gene, we assessed our promoters with strengths ranging from 4 to 106 % as compared to the pWEF31 expression vector (Lv D, Wang W, Wei D (2012) Construction of two vectors for gene expression in Trichoderma reesei. Plasmid 67(1):67-71). The promoter collection was used in a proof-of-principle approach to achieve the co-expression of an alkaline endoglucanase and an alkaline cellobiohydrolase. We observed higher activities of both cellulose degradation and biostoning by the co-expression of an endoglucanase and a cellobiohydrolase than the activities obtained by the expression of only endoglucanase or cellobiohydrolase. This study makes the process of engineering expression of multiple genes easier in T. reesei.
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Dextran-based fluorescent nanoprobes for sentinel lymph node mapping.
Biomaterials
PUBLISHED: 04-22-2014
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Biopsy of sentinel lymph node (SLN) has become a common practice to predict whether tumor metastasis has occurred, so proper SLN positioning tracers are highly required. Due to many drawbacks of SLN tracers currently used, developing ideal, biosafe SLN imaging agents is always an urgent issue. The current study designed a novel fluorescent nanoprobe for accurate SLN mapping. Dextran-based nanogel (DNG) was prepared through a highly efficient self-assembly assisted approach and serves as a multi-functional platform for conjugating wide spectra emitting fluorescent agents. The newly fabricated fluorescent DNG (FDNG) could be designed with optimum size and stable fluorescent intensity for specific SLN imaging. Furthermore, a long-term dynamic course in vivo (from 1 min to 72 h) revealed the satisfactory specificity, sensitivity, and stability for SLN mapping. Most importantly, both in vitro and in vivo evaluations indicated that FDNG had fine biosafety and biocompatibility with lymphatic endothelial cells. All these results supported that FDNG could be used as highly efficient molecular imaging probes for specific, sensitive, stable, non-invasive, and safe SLN mapping, which provides efficient and accurate location for SLN biopsy and thus predicts tumor metastasis as well as directs therapies. Besides, our recent studies further demonstrated that DNG could also serve as a specific and controllable drug carrier, indicating a potential application for specific therapies of various lymph-associated diseases.
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Vitamin K1 attenuates bile duct ligation-induced liver fibrosis in rats.
Scand. J. Gastroenterol.
PUBLISHED: 04-17-2014
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Vitamin K1 is used as a liver protection drug for cholestasis-induced liver fibrosis in China, but the mechanism of vitamin K1's action in liver fibrosis is unclear. In this study, a model of liver fibrosis was achieved via bile duct ligation in rats. The rats were then injected with vitamin K1, and the levels of serum aspartate aminotransferase, alanine transaminase, total bilirubin and the fibrotic grade score, collagen content, the expressions of ?-smooth muscle actin (SMA) and cytokeratin 19 (CK19) were measured on day 28 after ligation. The levels of the biochemical parameters, fibrotic score and collagen content were significantly reduced by treatment with vitamin K1 in bile duct-ligated rats. In addition, ?-SMA and CK19 expression was significantly reduced by vitamin K1 treatment in bile duct-ligated rats. These results suggested that vitamin K1 may attenuate liver fibrosis by inhibiting hepatic stellate cell activation in bile duct-ligated rats.
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Four-fold channels are involved in iron diffusion into the inner cavity of plant ferritin.
Biochemistry
PUBLISHED: 04-07-2014
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From an evolutionary point of view, plant and animal ferritins arose from a common ancestor, but plant ferritin exhibits different features as compared with the animal analogue. One major difference is that the 4-fold channels naturally occurring in plant ferritin are hydrophilic, whereas the 4-fold channels in animal ferritin are hydrophobic. Prior to this study, however, the function of the 4-fold channels in oxidative deposition of iron in phytoferritin remained unknown. To elucidate the role of the 4-fold channels in iron oxidative deposition in ferritin, three mutants of recombinant soybean seed H-2 ferritin (rH-2) were prepared by site-directed mutagenesis, which contained H193A/H197A, a 4-fold channel mutant, E165I/E167A/E171A, a 3-fold channel mutant, and E165I/E167A/E171A/H193A/H197A, where both 3- and 4-channels were mutated. Stopped-flow, electrode oximetry, and transmission electron microscopy (TEM) results showed that H193A/H197A and E165I/E167A/E171A exhibited a similar catalyzing activity of iron oxidation with each other, but a pronounced low activity compared to rH-2, demonstrating that both the 4-fold and 3-fold hydrophilic channels are necessary for iron diffusion in ferritin, followed by oxidation. Indeed, among all tested ferritin, the catalyzing activity of E165I/E167A/E171A/H193A/H197A was weakest because its 3- and 4- fold channels were blocked. These findings advance our understanding of the function of 4-fold channels of plant ferritin and the relationship of the structure and function of ferritin.
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Protein expression of hypoxia-inducible factor-1 alpha and hepatocellular carcinoma: a systematic review with meta-analysis.
Clin Res Hepatol Gastroenterol
PUBLISHED: 04-04-2014
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To investigate the relationship of protein expression of hypoxia-inducible factor-1 alpha (HIF-1?) with clinicopathological factors and prognosis of hepatocellular carcinoma (HCC).
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Phytochemicals and biological activities of poisonous genera of Ericaceae in China.
Nat Prod Commun
PUBLISHED: 04-03-2014
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The family Ericaceae is comprised of about 70 genera of which about 20 are found throughout China. Of these Ledum, Rhododendron, Enkianthus, Pieris, Craibiodendron, Gaultheria, Vaccinium, and Leucothoe are regarded as poisonous. Many species of these poisonous genera are used as Chinese herbal medicines for the treatment of, for example, inflammation, asthma, and coughs. Modem research has demonstrated that the toxic ingredients of these poisonous genera are chiefly tetracyclic diterpenes, which have adverse effects on the digestive, cardiovascular and nervous systems. Because various species of these poisonous genera also have medicinal functions, extensive studies of these plants have led to the identification of many kinds of compound. This paper compiles 306 compounds from the eight poisonous genera, reported in 141 references.
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Molecular epidemiological study of hepatitis B virus genotypes in Southwest, China.
J. Med. Virol.
PUBLISHED: 03-31-2014
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Hepatitis B virus (HBV) is highly endemic in Southwest China; an area with many ethnic minorities. Information about the genetic distribution of HBV is still limited. In 2010, a multistage cluster sampling method was carried out in the Southwest China. Five hundred forty serum samples of participants were collected. Polymerase chain reaction followed by nucleotide sequencing of parts of the HBV S and C genes was performed. HBV genotype and subgenotype were determined. Recombination analysis was carried out. HBV infectious markers, HBV DNA and mutations in the basic core promoter (BCP) A1762T/G1764A and G1896A were analyzed. The results show us that HBV genotypes C/D recombinant (38.6%), B (31.6%), and C (23.3%), were predominant in Southwest China. C/D4 (96.8%) was endemic in the Tibetan and B2 (43.5%) in Han, and C1 (66.7%) was predominant in the Yi minority. 67.5% (56/83) of genotype C/D was Hepatitis B surface antigen (HBsAg) positive/Hepatitis B e antigen (HBeAg) positive/HBV DNA?20,000?IU/ml, BCP A1762T/G1764A double mutation was frequent in genotype C and C/D, and G1896A was frequent in B and B/C. Thus, HBV genotypes distribution differed significantly in area and minority in Southwest China. C/D recombinant is endemic in the Tibetan, while B, C genotypes are predominant in Han minority. C/D recombinant exhibits higher frequency with HBeAg positive, high level of HBV DNA and BCP A1762T/G1764A double mutation.
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Emergency management of traumatic total scalp avulsion with microsurgical replantation.
Ulus Travma Acil Cerrahi Derg
PUBLISHED: 03-19-2014
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Total scalp avulsion is a rare but serious injury often resulting in defects of the hair-bearing skin, and it may even be life-threatening. Microsurgical hair-bearing scalp replantation is the first choice for the treatment of scalp avulsion. In this article, we describe the microsurgical replantation of two cases with total scalp avulsion. The avulsed scalp involved the hairy scalp, forehead, eyelids, ears, and part of the face. Initial management in the emergency department (ED) included correction of hemorrhagic shock with early blood transfusion, intravenous rehydration, and wound compression after rapid physical examination. A full trauma and preoperative workup prior to attempts at replantation needs to be performed to exclude any associated life-threatening injuries. Good form and function of the completely avulsed tissues and organs were achieved in both cases. Successful replantations can achieve the best esthetic and functional results when compared with other procedures. In addition to the microsurgical technique, preoperative evaluation and preparation in the ED are considered to be an important part of the successful salvage of the avulsed scalp.
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Transcriptional profiling of mammary gland in Holstein cows with extremely different milk protein and fat percentage using RNA sequencing.
BMC Genomics
PUBLISHED: 03-18-2014
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Recently, RNA sequencing (RNA-seq) has rapidly emerged as a major transcriptome profiling system. Elucidation of the bovine mammary gland transcriptome by RNA-seq is essential for identifying candidate genes that contribute to milk composition traits in dairy cattle.
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Optimisation of the mRNA secondary structure to improve the expression of interleukin-24 (IL-24) in Escherichia coli.
Biotechnol. Lett.
PUBLISHED: 03-14-2014
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Interleukin-24 (IL-24) is a novel cytokine selectively inhibiting proliferation of cancer cells but with little effect on normal cells. However, IL-24 is difficult to express in Escherichia coli. In this study, we optimised the secondary structure of the translation initiation region using computational approach to obtain non-fusion recombinant IL-24 (nrIL-24). The Gibbs free energy of the region was decreased from -22 to -9.07 kcal mol(-1), potentially promoting a loose secondary structure formation and improving the translation initiation efficiency. As a result, the expression of nrIL-24 was increased to 26 % of the total cellular protein from being barely initially detectable. nrIL-24 showed a concentration-dependent inhibition of A375 cells but had little effect on normal human cells. These results demonstrate that this method in increasing nrIL-24 expression is effective and efficient.
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A scalable and regioselective synthesis of 2-difluoromethyl pyridines from commodity chemicals.
Org. Lett.
PUBLISHED: 03-06-2014
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A scalable de novo synthesis of difluoromethyl pyridines from inexpensive materials is reported. The pyridyl subunit is built around the difluoromethyl group rather than a late stage introduction of this moiety. This user-friendly approach allows access to a diverse range of substitution patterns on all positions on the ring system and on the difluoromethyl group.
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Antagonistic effect of protein extracts from Streptococcus sanguinis on pathogenic bacteria and fungi of the oral cavity.
Exp Ther Med
PUBLISHED: 02-24-2014
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An antibacterial substance from Streptococcus sanguinis (S. sanguinis) is known to have an inhibitory effect on putative periodontal pathogens, but its inhibitory effect on pathogens of oral candidiasis is unknown. In this study, intracellular and exocrine proteins were extracted from S. sanguinis. The antagonistic effect of the protein extracts on Prevotella intermedia (P. intermedia) and Porphyromonas gingivalis (P. gingivalis) was detected by a well-plate technique, and the effects of the protein extracts on biofilms formed by these bacteria were evaluated by confocal laser scanning microscopy. The antagonistic effect of the protein extracts on pathogenic fungi was investigated using Candida albicans (C. albicans) and Candida tropicalis (C. tropicalis). The growth curves of C. albicans and C. tropicalis were determined from ultraviolet absorption measurements, their morphological changes following treatment were observed by optical microscopy and scanning electron microscopy, and the effects of the protein extracts on the thickness of their biofilms and the distribution of dead/live bacteria within the biofilms were detected by confocal laser scanning microscopy. The results showed significant inhibitory effects of the intracellular proteins extracted from S. sanguinis on pathogenic bacteria (P. intermedia and P. gingivalis), fungi (C. albicans and C. tropicalis) and the biofilms formed by them. Furthermore, the growth curves and morphology of C. albicans and C. tropicalis were altered following treatment with the intracellular proteins, resulting in disc-like depressions in the surfaces of the fungal spores and mycelia. By contrast, the exocrine proteins demonstrated no significant inhibitory effect on the pathogenic bacteria, fungi and the biofilms formed by them. Thus, it may be concluded that intracellular proteins of S. sanguinis have antibacterial activity and exert an antagonistic effect on certain pathogenic bacteria and fungi of the oral cavity.
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Closure of large defects after microcystic lymphatic malformations using lateral intercostal artery perforator flap.
J Plast Reconstr Aesthet Surg
PUBLISHED: 02-19-2014
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The surgical treatment of microcystic lymphatic malformations (LMs) has historically been difficult and frustrating because of a high recurrence rate due to incomplete resection. However, complete removal of the multifocal and extensive lesions rely on accurate imaging diagnosis and effective repair methods for the resulting large defect. The purpose of this study was to repair large skin defects due to complete resection of microcystic LMs using lateral intercostal artery perforator (LICAP) flap.
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Multiplex hydrolysis probe real-time PCR for simultaneous detection of hepatitis A virus and hepatitis E virus.
Int J Mol Sci
PUBLISHED: 02-11-2014
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Detection of hepatitis viral infections has traditionally relied on the circulating antibody test using the enzyme-linked immunosorbent assay. However, multiplex real-time PCR has been increasingly used for a variety of viral nucleic acid detections and has proven to be superior to traditional methods. Hepatitis A virus (HAV) and hepatitis E virus (HEV) are the major causes of acute hepatitis worldwide; both HAV and HEV infection are a main public health problem. In the present study, a one-step multiplex reverse transcriptase quantitative polymerase chain reaction assay using hydrolysis probes was developed for simultaneously detecting HAV and HEV. This novel detection system proved specific to the target viruses, to be highly sensitive and to be applicable to clinical sera samples, making it useful for rapid, accurate and feasible identification of HAV and HEV.
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CTHRC1 acts as a prognostic factor and promotes invasiveness of gastrointestinal stromal tumors by activating Wnt/PCP-Rho signaling.
Neoplasia
PUBLISHED: 02-10-2014
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Gastrointestinal stromal tumors (GISTs) are the major gastrointestinal mesenchymal tumors with a variable malignancy ranging from a curable disorder to highly malignant sarcomas. Metastasis and recurrence are the main causes of death in GIST patients. To further explore the mechanism of metastasis and to more accurately estimate the recurrence risk of GISTs after surgery, the clinical significance and functional role of collagen triple helix repeat containing-1 (CTHRC1) in GIST were investigated. We found that CTHRC1 expression was gradually elevated as the risk grade of NIH classification increased, and was closely correlated with disease-free survival and overall survival in 412 GIST patients. In vitro experiments showed that recombinant CTHRC1 protein promoted the migration and invasion capacities of primary GIST cells. A luciferase reporter assay and pull down assay demonstrated that recombinant CTHRC1 protein activated noncanonical Wnt/PCP-Rho signaling but inhibited canonical Wnt signaling. The pro-motility effect of CTHRC1 on GIST cells was reversed by using a Wnt5a neutralizing antibody and inhibitors of Rac1 or ROCK. Taken together, these data indicate that CTHRC1 may serve as a new predictor of recurrence risk and prognosis in post-operative GIST patients and may play an important role in facilitating GIST progression. Furthermore, CTHRC1 promotes GIST cell migration and invasion by activating Wnt/PCP-Rho signaling, suggesting that the CTHRC1-Wnt/PCP-Rho axis may be a new therapeutic target for interventions against GIST invasion and metastasis.
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Standard plane localization in ultrasound by radial component model and selective search.
Ultrasound Med Biol
PUBLISHED: 01-25-2014
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Acquisition of the standard plane is crucial for medical ultrasound diagnosis. However, this process requires substantial experience and a thorough knowledge of human anatomy. Therefore it is very challenging for novices and even time consuming for experienced examiners. We proposed a hierarchical, supervised learning framework for automatically detecting the standard plane from consecutive 2-D ultrasound images. We tested this technique by developing a system that localizes the fetal abdominal standard plane from ultrasound video by detecting three key anatomical structures: the stomach bubble, umbilical vein and spine. We first proposed a novel radial component-based model to describe the geometric constraints of these key anatomical structures. We then introduced a novel selective search method which exploits the vessel probability algorithm to produce probable locations for the spine and umbilical vein. Next, using component classifiers trained by random forests, we detected the key anatomical structures at their probable locations within the regions constrained by the radial component-based model. Finally, a second-level classifier combined the results from the component detection to identify an ultrasound image as either a "fetal abdominal standard plane" or a "non- fetal abdominal standard plane." Experimental results on 223 fetal abdomen videos showed that the detection accuracy of our method was as high as 85.6% and significantly outperformed both the full abdomen and the separate anatomy detection methods without geometric constraints. The experimental results demonstrated that our system shows great promise for application to clinical practice.
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The effects of titania nanotubes with embedded silver oxide nanoparticles on bacteria and osteoblasts.
Biomaterials
PUBLISHED: 01-23-2014
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A versatile strategy to endow biomaterials with long-term antibacterial ability without compromising the cytocompatibility is highly desirable to combat biomaterial related infection. TiO2 nanotube (NT) arrays can significantly enhance the functions of many cell types including osteoblasts thus having promising applications in orthopedics, orthodontics, as well as other biomedical fields. In this study, TiO2 NT arrays with Ag2O nanoparticle embedded in the nanotube wall (NT-Ag2O arrays) are prepared on titanium (Ti) by TiAg magnetron sputtering and anodization. Well-defined NT arrays containing Ag concentrations in a wide range from 0 to 15 at % are formed. Ag incorporation has little influence on the NT diameter, but significantly decreases the tube length. Crystallized Ag2O nanoparticles with diameters ranging from 5 nm to 20 nm are embedded in the amorphous TiO2 nanotube wall and this unique structure leads to controlled release of Ag(+) that generates adequate antibacterial activity without showing cytotoxicity. The NT-Ag2O arrays can effectively kill Escherichia coli and Staphylococcus aureus even after immersion for 28 days, demonstrating the long lasting antibacterial ability. Furthermore, the NT-Ag2O arrays have no appreciable influence on the osteoblast viability, proliferation, and differentiation compared to the Ag free TiO2 NT arrays. Ag incorporation even shows some favorable effects on promoting cell spreading. The technique reported here is a versatile approach to develop biomedical coatings with different functions.
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Elevated expression of TANK-binding kinase 1 enhances tamoxifen resistance in breast cancer.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-21-2014
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Resistance to antiestrogens is one of the major challenges in breast cancer treatment. Although phosphorylation of estrogen receptor ? (ER?) is an important factor in endocrine resistance, the contributions of specific kinases in endocrine resistance are still not fully understood. Here, we report that an important innate immune response kinase, the I?B kinase-related TANK-binding kinase 1 (TBK1), is a crucial determinant of resistance to tamoxifen therapies. We show that TBK1 increases ER? transcriptional activity through phosphorylation modification of ER? at the Ser-305 site. Ectopic TBK1 expression impairs the responsiveness of breast cancer cells to tamoxifen. By studying the specimens from patients with breast cancer, we find a strong positive correlation of TBK1 with ER?, ER? Ser-305, and cyclin D1. Notably, patients with tumors highly expressing TBK1 respond poorly to tamoxifen treatment and show high potential for relapse. Therefore, our findings suggest that TBK1 contributes to tamoxifen resistance in breast cancer via phosphorylation modification of ER?.
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Self-assembly of Terbium(III)-based metal-organic complexes with two-photon absorbing active.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 01-16-2014
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Hybrid complexes based on D-?-A type dyes p-aminostyryl-pyridinum and Terbium(III) complex anion (1, 2) have been synthesized by ionic exchange reaction. Meanwhile two different alkyl-substituted amino groups were used as electron donors in organic dyes cations. The synthesized complexes were characterized by element analysis. In addition, the structural features of them were systematic studied by single crystal X-ray diffraction analysis. Their linear properties have been systematically investigated by absorption spectra and fluorescence, the results show that the energy transfer takes place from the trans-4-[4'-(N,N-diethylamino)styryl]-N-methyl pyridinium (2') cation to Tb(III). In addition, complex 2 exhibit a large two-photon absorption coefficient ?: 0.044cm/GW at 710nm.
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Synthesis of pyridyl-dihydrobenzooxaphosphole ligands and their application in asymmetric hydrogenation of unfunctionalized alkenes.
J. Org. Chem.
PUBLISHED: 01-14-2014
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Synthesis of the electron-rich 2-substituted-6-(phenylsulfonyl)pyridines is presented. A series of air-stable, tunable, P-chiral pyridyl-dihydrobenzooxaphosphole ligands were designed and synthesized by a diastereoselective S(N)Ar substitution of the corresponding sulfonyl pyridines. The ligands were successfully applied in the Ir-catalyzed asymmetric hydrogenation of unfunctionalized alkenes with good enantioselectivities.
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Tryptase inhibitor APC 366 prevents hepatic fibrosis by inhibiting collagen synthesis induced by tryptase/protease-activated receptor 2 interactions in hepatic stellate cells.
Int. Immunopharmacol.
PUBLISHED: 01-10-2014
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Protease-activated receptor (PAR) 2 is a G-protein-coupled receptor that is activated by mast cell tryptase. PAR-2 activation augments profibrotic pathways through the induction of extracellular matrix proteins. PAR-2 is widely expressed in hepatic stellate cells (HSCs), but the role of tryptase/PAR-2 interaction in liver fibrosis is unclear. We studied the development of bile duct ligation (BDL)-induced hepatic fibrosis in rats treated with mast cell tryptase inhibitor APC 366, and showed that APC 366 reduced hepatic fibrosis scores, collagen content and serum biochemical parameters. Reduced fibrosis was associated with decreased expression of PAR-2 and ?-smooth muscle actin (?-SMA). Our findings demonstrate that mast cell tryptase induces PAR-2 activation to augment HSC proliferation and promote hepatic fibrosis in rats. Treatment with tryptase antagonists may be a novel therapeutic approach to prevent fibrosis in patients with chronic liver disease.
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HMGB1 Is Involved in the Protective Effect of the PPAR ? Agonist Fenofibrate against Cardiac Hypertrophy.
PPAR Res
PUBLISHED: 01-09-2014
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High mobility group box 1 (HMGB1) is a ubiquitous nuclear DNA-binding protein whose function is dependent on its cellular location. Extracellular HMGB1 is regarded as a delayed mediator of proinflammatory cytokines for initiating and amplifying inflammatory responses, whereas nuclear HMGB1 has been found to prevent cardiac hypertrophy and heart failure. Because fenofibrate, a peroxisome proliferator-activated receptor ? (PPAR ? ) agonist, has shown both protective effects against cardiac hypertrophy and inhibitory effects against inflammation, the potential modulation of HMGB1 expression and secretion by fenofibrate is of great interest. We herein provide evidence that fenofibrate modulates basal and LPS-stimulated HMGB1 expression and localization in addition to secretion of HMGB1 in cardiomyocytes. In addition, administration of fenofibrate to mice prevented the development of cardiac hypertrophy induced by thoracic transverse aortic constriction (TAC) while increasing levels of nuclear HMGB1. Altogether, these data suggest that fenofibrate may inhibit the development of cardiac hypertrophy by regulating HMGB1 expression, which provides a new potential strategy to treat cardiac hypertrophy.
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Synthesis, crystal structures and spectral properties of 6'-phenyl-2,2'-bipyridine derivatives and their CdLI(2) complexes.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 01-07-2014
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Two novel 6'-phenyl-2,2'-bipyridine ligands (L1, L2) and their CdL(1,2)I2 complexes (1, 2) were synthesized and characterized by elemental analysis, (1)H NMR, IR, MALDI-TOF spectroscopy, and single crystal X-ray diffraction analysis. The results reveal that the central cadmium(II) atom in the complexes was coordinated by two iodide ions and two nitrogen atoms from L1, L2, forming a distorted coordination geometry. The electronic absorption properties of them were investigated on the basis of theoretical calculations (TD-DFT).
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Genetic diversity and population structure of Rheum tanguticum (Dahuang) in China.
Chin Med
PUBLISHED: 01-01-2014
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Wild Rheum tanguticum (Dahuang in Chinese) has becoming endangered in China. This study aims to examine the genetic structure and genetic diversity of R. tanguticum within species, and the genetic differentiation within and among populations in China.
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Epidemiology of hepatitis e virus in china: results from the third national viral hepatitis prevalence survey, 2005-2006.
PLoS ONE
PUBLISHED: 01-01-2014
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In China, hepatitis E virus (HEV) is prevalent and causes disease, but its epidemiological profile is not well understood. We used a commercial enzyme-linked immunosorbent assay to detect total antibodies to hepatitis E virus in 15,862 serum samples collected during the Third National Viral Hepatitis Prevalence Survey. The results were analyzed to calculate estimates of HEV seroprevalence and to examine the effects of some putative risk factors. The seroprevalence of HEV in the general Chinese population during the period from 2005 through 2006 was 23.46% (95% confidence interval [CI], 18.41%-28.50%). The farming population, the age group of 15-60 year olds, and those living in the Midwest or Mideast region and in Xinjiang province had the highest seroprevalence estimates. The prevalence of HEV is high in China. The seroprevalence rate of HEV shows an unbalanced distribution among areas with different geographic location and economic development levels. The characteristics of the distribution associated may be due to the route of HEV transmission (via contaminated water or animal reservoirs). Within the same region, the seroprevalence of HEV is generally increased with age.
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Effect of reduced energy density of close-up diets on dry matter intake, lactation performance and energy balance in multiparous Holstein cows.
J Anim Sci Biotechnol
PUBLISHED: 01-01-2014
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Energy intake prepartum is critically important to health, milk performance, and profitability of dairy cows. The objective of this study was to determine the effect of reduced energy density of close-up diets on dry matter intake (DMI), lactation performance and energy balance (EB) in multiparous Holstein cows which were housed in a free-stall barn and fed for ad libitum intake. Thirty-nine dry cows were blocked and assigned randomly to three groups fed a high energy density diet [HD, n?=?13; 6.8 MJ of net energy for lactation (NEL)/kg; 14.0% crude protein (CP) ], or a middle energy density diet (MD, n?=?13; 6.2 MJ NEL/kg; 14.0% CP), or a low energy density diet (LD, n?=?13; 5.4 MJ NEL/kg; 14.0% CP) from d 21 before expected day of calving. After parturition, all cows were fed the same lactation diet to d 70 in milk (DIM). The DMI and NEL intake prepartum were decreased by the reduced energy density diets (P?
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Genome wide association study identifies 20 novel promising genes associated with milk fatty acid traits in Chinese Holstein.
PLoS ONE
PUBLISHED: 01-01-2014
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Detecting genes associated with milk fat composition could provide valuable insights into the complex genetic networks of genes underling variation in fatty acids synthesis and point towards opportunities for changing milk fat composition via selective breeding. In this study, we conducted a genome-wide association study (GWAS) for 22 milk fatty acids in 784 Chinese Holstein cows with the PLINK software. Genotypes were obtained with the Illumina BovineSNP50 Bead chip and a total of 40,604 informative, high-quality single nucleotide polymorphisms (SNPs) were used. Totally, 83 genome-wide significant SNPs and 314 suggestive significant SNPs associated with 18 milk fatty acid traits were detected. Chromosome regions that affect milk fatty acid traits were mainly observed on BTA1, 2, 5, 6, 7, 9, 13, 14, 18, 19, 20, 21, 23, 26 and 27. Of these, 146 SNPs were associated with more than one milk fatty acid trait; most of studied fatty acid traits were significant associated with multiple SNPs, especially C18:0 (105 SNPs), C18 index (93 SNPs), and C14 index (84 SNPs); Several SNPs are close to or within the DGAT1, SCD1 and FASN genes which are well-known to affect milk composition traits of dairy cattle. Combined with the previously reported QTL regions and the biological functions of the genes, 20 novel promising candidates for C10:0, C12:0, C14:0, C14:1, C14 index, C18:0, C18:1n9c, C18 index, SFA, UFA and SFA/UFA were found, which composed of HTR1B, CPM, PRKG1, MINPP1, LIPJ, LIPK, EHHADH, MOGAT1, ECHS1, STAT1, SORBS1, NFKB2, AGPAT3, CHUK, OSBPL8, PRLR, IGF1R, ACSL3, GHR and OXCT1. Our findings provide a groundwork for unraveling the key genes and causal mutations affecting milk fatty acid traits in dairy cattle.
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A Novel EGFR Isoform Confers Increased Invasiveness to Cancer Cells.
Cancer Res.
PUBLISHED: 11-15-2013
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As a validated therapeutic target in several human cancers, the EGF receptor (EGFR) provides a focus to gain deeper insights into cancer pathophysiology. In this study, we report the identification of a naturally occurring and widely expressed EGFR isoform termed EGFRvA, which substitutes a Ser/Thr-rich peptide for part of the carboxyl-terminal regulatory domain of the receptor. Intriguingly, EGFRvA expression relates more closely to histopathologic grade and poor prognosis in patients with glioma. Ectopic expression of EGFRvA in cancer cells conferred a higher invasive capacity than EGFR in vitro and in vivo. Mechanistically, EGFRvA stimulated expression of STAT3, which upregulated heparin-binding EGF (HB-EGF). Reciprocally, HB-EGF stimulated phosphorylation of EGFRvA at Y845 along with STAT3, generating a positive feedback loop that may reinforce invasive function. The significance of EGFRvA expression was reinforced by findings that it is attenuated by miR-542-5p, a microRNA that is a known tumor suppressor. Taken together, our findings define this newfound EGFR isoform as a key theranostic molecule. Cancer Res; 73(23); 7056-67. ©2013 AACR.
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Changes in ruminal fermentation, milk performance and milk fatty acid profile in dairy cows with subacute ruminal acidosis and its regulation with pelleted beet pulp.
Arch Anim Nutr
PUBLISHED: 11-05-2013
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The aims of the experiment were to investigate the variation in ruminal fermentation, milk performance and milk fatty acid profile triggered by induced subacute ruminal acidosis (SARA); and to evaluate the ability of beet pulp (BP) as a replacement for ground maize in order to alleviate SARA. Eight Holstein-Friesian cows were fed four diets (total mixed rations) during four successive periods (each of 17 d): (1) without wheat (W0); (2) with 10% finely ground wheat (FGW) (W10); (3) with 20% FGW (W20); (4) with 20% FGW and 10% pelleted BP (BP10). Inducing SARA by diet W20 decreased the daily mean ruminal pH (6.37 vs. 5.94) and the minimum ruminal pH (5.99 vs. 5.41) from baseline to challenge period. Ruminal concentrations of total volatile fatty acid, propionate, butyrate, valerate and isovalerate increased with the W20 compared with the W0 and W10 treatments. The substitution of BP for maize increased the minimum ruminal pH and molar percentage of acetate and decreased the molar percentage of butyrate. The diets had no effect on dry matter intake (DMI) and milk yield, but the milk fat percentage and yield as well as the amount of fat-corrected milk was reduced in the W20 and BP10 treatments. The cows fed the W20 diet had greater milk concentrations of C11:0, C13:0, C15:0, C14:1, C16:1, C17:1, C18:2n6c, C20:3n6, total polyunsaturated fatty acids (FA) and total odd-chain FA, and lower concentrations of C18:0 and total saturated FA compared with the cows fed the W0 diet. Therefore, it can be concluded that changes in ruminal fermentation, milk fat concentration and fatty acid profile are highly related to SARA induced by feeding high FGW diets, and that the substitution of BP for maize could reduce the risk of SARA in dairy cows.
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Comprehensive analysis of the functional microRNA-mRNA regulatory network identifies miRNA signatures associated with glioma malignant progression.
Nucleic Acids Res.
PUBLISHED: 11-04-2013
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Glioma is the most common and fatal primary brain tumour with poor prognosis; however, the functional roles of miRNAs in glioma malignant progression are insufficiently understood. Here, we used an integrated approach to identify miRNA functional targets during glioma malignant progression by combining the paired expression profiles of miRNAs and mRNAs across 160 Chinese glioma patients, and further constructed the functional miRNA-mRNA regulatory network. As a result, most tumour-suppressive miRNAs in glioma progression were newly discovered, whose functions were widely involved in gliomagenesis. Moreover, three miRNA signatures, with different combinations of hub miRNAs (regulations?30) were constructed, which could independently predict the survival of patients with all gliomas, high-grade glioma and glioblastoma. Our network-based method increased the ability to identify the prognostic biomarkers, when compared with the traditional method and random conditions. Hsa-miR-524-5p and hsa-miR-628-5p, shared by these three signatures, acted as protective factors and their expression decreased gradually during glioma progression. Functional analysis of these miRNA signatures highlighted their critical roles in cell cycle and cell proliferation in glioblastoma malignant progression, especially hsa-miR-524-5p and hsa-miR-628-5p exhibited dominant regulatory activities. Therefore, network-based biomarkers are expected to be more effective and provide deep insights into the molecular mechanism of glioma malignant progression.
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Effects of PGE2 EP3/EP4 receptors on bladder dysfunction in mice with experimental autoimmune encephalomyelitis.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 10-23-2013
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To investigate the expression of four subtypes of PGE2 E-prostanoid (EP) receptors (EP1-EP4) and the effects of EP3/EP4 on bladder dysfunction in a new neurogenic bladder model induced by experimental autoimmune encephalomyelitis (EAE), the mouse model of EAE was induced using a previously established method, and bladder function in mice with different defined levels of neurological impairment was then examined, including micturition frequencies and voiding weight. Bladders were then harvested for analysis of EP receptor expression by Western blot. Activities of agonists/antagonists of EP3 and EP4 receptors as well as PGE2 were also evaluated at different stages of EAE. The results showed that EAE mice developed profound bladder dysfunction characterized by significantly increased micturition and significantly decreased urine output per micturition. EAE-induced upregulation of EP3 and EP4 receptors in the bladder was accompanied by bladder dysfunction. However, EAE had no significant effect on EP1 and EP2 receptors. Moreover, PGE2 and agonists/antagonists of EP3 and EP4 receptors significantly affected bladder dysfunction in EAE mice. Thus, we believe that EAE mice are useful for investigations of the neurogenic bladder. In addition, EP3 and EP4 receptors play a role in EAE-induced bladder dysfunction, providing us with a new target for the treatment of neurogenic bladders.
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Magnetic field sensing based on singlemode-multimode-singlemode fiber structures using magnetic fluids as cladding.
Opt Lett
PUBLISHED: 10-02-2013
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Magnetic field sensing based on magnetic fluid (MF) and a singlemode-multimode-singlemode (SMS) fiber structure is proposed. The sensitivity of the proposed sensing system can be enhanced by corroding the cladding of the multimode fiber of the SMS fiber structure. The achieved maximum magnetic field sensitivity of our experimental structures is -16.86 pm/Oe as the fiber is corroded for 1680 s. The visibility of the interference dip for the MF-clad SMS fiber structure decreases with corrosion time. Considering the trade-off between sensitivity and visibility, the figure of merit of the sensing system is employed to evaluate the sensing performance comprehensively. In our experiments, the structure corroded for ~1620 s is found to have maximum sensing performance.
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High expression of small hepatitis D antigen in Escherichia coli and ELISA for diagnosis of hepatitis D virus.
J. Virol. Methods
PUBLISHED: 09-29-2013
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Hepatitis D virus (HDV) infection is often accompanied by hepatitis B virus (HBV) infection. Co-infection of HDV and HBV may lead to more severe symptoms and even death. Current methods for HDV diagnosis have high false-positive rates and show significant result discrepancies. The Abbott AxSYM AUSAB test, currently a standard test for HDV detection, is too laborious and expensive for routine application. Therefore, new sensitive and cost-efficient methods for HDV diagnosis are urgently needed. In this study, S-HDAg protein was produced in high yield in Escherichia coli. Optimal protein production was achieved by optimization of S-HDAg gene codons according to the codon preference of E. coli and using host cells with appropriate cell density. Under optimal expression conditions, the S-HDAg protein expression yield (30mg/l) was the highest among any proteins expressed in E. coli. A standard enzyme-linked immunosorbent assay (ELISA) for HDV was developed using the purified S-HDAg protein, which showed high specificity against hepatitis B, C, D and E viruses. Overall, the ELISA had superior specificity and sensitivity compared with the Abbott AxSYM AUSAB test and was also more convenient and cost-efficient.
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Maternal influenza-like illness, medication use during pregnancy and risk of congenital heart defects in offspring.
J. Matern. Fetal. Neonatal. Med.
PUBLISHED: 09-27-2013
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Abstract Objective: To evaluate the association between maternal influenza and congenital heart defects (CHDs), and whether the use of traditional Chinese medicine (TCM) or Western medicine (antibiotics, antipyretic-analgesic drugs) modified this association. Method: We analysed 294 fetuses with CHDs and 416 control fetuses without any abnormalities identified from February 2010 through October 2011 in this hospital-based case-control study. Participating mothers were interviewed to determine whether they had been infected with "influenza" during the early pregnancy period or had used any medicine (TCM, Western medicine) to treat influenza. A logistic regression model was used to calculate ORs and 95% CIs while controlling for potential confounders. Results: There were significant associations between maternal influenza and CHDs in the aggregate (AOR, 1.60; 95%CI, 1.12 to 2.28) and specific subtypes, namely septal defects (AOR, 2.12; 95%CI, 1.38 to 3.26) and conotruncal defects (AOR, 1.60; 95%CI, 1.01 to 2.51). Maternal medication use (i.e. TCM or Western medicine) in the setting of influenza tended to decrease these associations. Conclusions: Maternal influenza during second-third months of pregnancy increased the risk for CHDs, with septal defects and conotruncal defects in particular being observed. The use of medication for influenza might attenuate such associations.
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Change in hepatitis B virus large surface antigen variant prevalence 13 years after implementation of a universal vaccination program in China.
J. Virol.
PUBLISHED: 09-04-2013
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A nationwide hepatitis B virus (HBV) vaccination program was implemented in China starting in 1992. To study the change in HBV variant prevalence with massive immunization, large HBV surface protein (LHBs) genes from HBV surface antigen (HBsAg)-positive sera were amplified and sequenced. The prevalences of LHBs mutants were compared between the 1992 and 2005 surveys in child and adult groups. The prevalence of "?" determinant mutants in the children increased from 6.5% in 1992 to 14.8% in 2005, where the G145R mutant occurred most frequently. In contrast, mutation frequencies showed little difference between 1992 (9.4%) and 2005 (9.9%) in adults. Moreover, compared to the 1992 survey, the child group surface (S) protein mutation frequency specifically increased (P = 0.005) in the 2005 survey, but the pre-S region mutation frequency did not show a significant difference (P > 0.05). However, the mutation frequency in the adult group increased in both the pre-S and S regions. Furthermore, the frequencies of the disease-related pre-S2 deletion and start codon mutations were significantly higher in the adult groups than in the child groups in both the 1992 and 2005 surveys (P < 0.01). Massive immunization enhances the HBV S protein mutation; the prevalence of LHBs mutants, particularly disease-related mutants, tends to increase with patient age.
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Reprint of: Epidemiological serosurvey of Hepatitis B in China-Declining HBV prevalence due to Hepatitis B vaccination.
Vaccine
PUBLISHED: 08-12-2013
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To determine the prevalence of hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core anti-body (anti-HBc) in a representative population in China 14 years after introduction of hepatitis B vaccination of infants.
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Construction and immunological evaluation of truncated hepatitis B core particles carrying HBsAg amino acids 119-152 in the major immunodominant region (MIR).
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-02-2013
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Hepatitis B capsid protein expressed in Escherichia coli can reassemble into icosahedral particles, which could strongly enhance the immunogenicity of foreign epitopes, especially those inserted into its major immunodominant region. Herein, we inserted the entire ? antigenic determinant amino acids (aa) 119-152 of HBsAg into the truncated HBc (aa 1-144), between Asp(78) and Pro(79). Prokaryotic expression showed that the mosaic HBc was mainly in the form of inclusion bodies. After denaturation with urea, it was dialyzed progressively for protein renaturation. We observed that before and after renaturation, mosaic HBc was antigenic as determined by HBsAg ELISA and a lot of viruslike particles were observed after renaturation. Thus, we further purified the mosaic viruslike particles by (NH4)2SO4 precipitation, DEAE chromatography, and Sepharose 4FF chromatography. Negative staining electron microscopy demonstrated the morphology of the viruslike particles. Immunization of Balb/c mice with mosaic particles induced the production of anti-HBs antibody and Th1 cell immune response supported by ELISPOT and CD4/CD8 proportions assay. In conclusion, we constructed mosaic hepatitis core particles displaying the entire ? antigenic determinant on the surface and laid a foundation for researching therapeutic hepatits B vaccines.
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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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