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Find video protocols related to scientific articles indexed in Pubmed.
Impact of surface plasmon polaritons and other waves on the radiation of a dipole emitter close to a metallic nanowire antenna.
Opt Express
PUBLISHED: 11-18-2014
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The radiation of a dipole emitter close to a metallic nanowire optical antenna is investigated theoretically. By considering the excitation and multiple scattering of surface plasmon polaritons (SPPs) on the antenna and neglecting all other surface waves, we build up an intuitive pure-SPP model to comprehensively describe the radiation of the antenna. The model shows that for antennas with short lengths that support lower orders of resonance, waves other than SPPs contribute considerably to the antenna radiation, while SPPs play a dominant role for other cases. The enhancement of the antenna radiation is shown arising from two contributions, the field directly radiated by the emitter and the field resonantly excited by the surface waves on the antenna.
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Quantitative coupled-mode model for a metal-dielectric-metal waveguide with a side-coupled cavity.
J Opt Soc Am A Opt Image Sci Vis
PUBLISHED: 11-18-2014
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The Fabry-Perot model is proposed to analyze the wavelength-selective transmission behaviors of the metal-dielectric-metal waveguide with a rectangular side-coupled cavity. The guided modes propagating in the waveguide and the cavity are extracted by the aperiodic Fourier modal method (a-FMM). The scattering coefficients that appeared in the model are calculated by the a-FMM and the normal-mode theory. The applications of such structure in the wavelength-selective filter and the refractive index sensor are also discussed. Our model is shown to accurately predict the fully vectorial data and thus can provide reliable and quantitative analysis of this kind of device.
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Reduction of CO2 using a Rhenium Bipyridine Complex Containing Ancillary BODIPY Moieties.
Catal Today
PUBLISHED: 11-15-2014
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The reduction of carbon dioxide to chemical fuels such as carbon monoxide is an important challenge in the field of renewable energy conversion. Given the thermodynamic stability of carbon dioxide, it is difficult to efficiently activate this substrate in a selective fashion and the development of new electrocatalysts for CO2 reduction is of prime importance. To this end, we have prepared and studied a new fac-Re(I)(CO)3 complex supported by a bipyridine ligand containing ancillary BODIPY moieties ([Re(BB2)(CO)3Cl]). Voltammetry experiments revealed that this system displays a rich redox chemistry under N2, as [Re(BB2)(CO)3Cl] can be reduced by up to four electrons at modest potentials. These redox events have been characterized as the Re(I/0) couple, and three ligand based reductions - two of which are localized on the BODIPY units. The ability of the BB2 ligand to serve as a non-innocent redox reservoir is manifest in an enhanced electrocatalysis with CO2 as compared to an unsubstituted Re-bipyridine complex lacking BODIPY units ([Re(bpy)(CO)3Cl]). The second order rate constant for reduction of CO2 by [Re(BB2)(CO)3Cl] was measured to be k = 3400 M(-1)s(-1) at an applied potential of -2.0 V versus SCE, which is roughly three times greater than the corresponding unsubstituted Re-bipyridine homologue. Photophysical and photochemical studies were also carried out to determine if [Re(BB2)(CO)3Cl] was a competent platform for CO2 reduction using visible light. These experiments showed that this complex supports unusual excited state dynamics that precludes efficient CO2 reduction and are distinct from those that are typically observed for fac-Re(I)(CO)3 complexes.
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Differential gene expression profiles of peripheral blood mononuclear cells in childhood asthma.
J Asthma
PUBLISHED: 10-21-2014
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Abstract Objective: Asthma is a common childhood disease with strong genetic components. This study compared whole-genome expression differences between asthmatic young children and healthy controls to identify gene signatures of childhood asthma. Methods: Total RNA extracted from peripheral blood mononuclear cells (PBMC) was subjected to microarray analysis. QRT-PCR was performed to verify the microarray results. Classification and functional characterization of differential genes were illustrated by hierarchical clustering and gene ontology analysis. Multiple logistic regression (MLR) analysis, receiver operating characteristic (ROC) curve analysis, and discriminate power were used to scan asthma-specific diagnostic markers. Results: For fold-change>2 and p?
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Electrochemical, spectroscopic, and (1)o2 sensitization characteristics of 10,10-dimethylbiladiene complexes of zinc and copper.
J Phys Chem A
PUBLISHED: 10-07-2014
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The synthesis, electrochemistry, and photophysical characterization of a 10,10-dimethylbiladiene tetrapyrrole bearing ancillary pentafluorophenyl groups at the 5- and 15-meso positions (DMBil1) is presented. This nonmacrocyclic tetrapyrrole platform is robust and can serve as an excellent ligand scaffold for Zn(2+) and Cu(2+) centers. X-ray diffraction studies conducted for DMBil1 along with the corresponding Zn[DMBil1] and Cu[DMBil1] complexes show that this ligand scaffold binds a single metal ion within the tetrapyrrole core. Additionally, electrochemical experiments revealed that all three of the aforementioned compounds display an interesting redox chemistry as the DMBil1 framework can be both oxidized and reduced by two electrons. Spectroscopic and photophysical experiments carried out for DMBil1, Zn[DMBil1], and Cu[DMBil1] provide a basic picture of the electronic properties of these platforms. All three biladiene derivatives strongly absorb light in the visible region and are weakly emissive. The ability of these compounds to sensitize the formation of (1)O2 at wavelengths longer than 500 nm was probed. Both the free base and Zn(2+) 10,10-dimethylbiladiene architectures show modest efficiencies for (1)O2 sensitization. The combination of structural, electrochemical, and photophysical data detailed herein provides a basis for the design of additional biladiene constructs for the activation of O2 and other small molecules.
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[Effect of toll-like receptor (TLR) 7 deficiencies on the in vivo immune response against Schistosoma japonicum].
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi
PUBLISHED: 09-17-2014
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To explore the toll-like receptor 7 knocked out (TLR7-/-) mice immune response against Schistosoma japonicum.
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Serum parathyroid hormone as a potential novel biomarker of coronary heart disease.
Genet Test Mol Biomarkers
PUBLISHED: 09-05-2014
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This study aimed to evaluate the relationships between serum parathyroid hormone (PTH) and coronary heart disease (CHD).
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5-Caffeoylquinic acid decreases diet-induced obesity in rats by modulating PPAR? and LXR? transcription.
J. Sci. Food Agric.
PUBLISHED: 09-03-2014
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Chlorogenic acids (CGAs) are widely distributed in plant material, including foods and beverages. 5-Caffeoylquinic acid (5-CQA) is the most studied CGA, but the mechanism of its hypolipidaemic effect remains unclear. This study aimed to determine the effect of 5-CQA on lipid metabolism in the liver of Sprague-Dawley rats fed a high-fat diet (HFD).
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Synthesis and anticancer evaluation of benzyloxyurea derivatives.
Chem. Pharm. Bull.
PUBLISHED: 09-02-2014
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A series of novel benzyloxyurea derivatives was designed, synthesized by substituting different benzyls or phenyls on N,N'-positions of the hydroxyurea (HU). These target compounds were evaluated for their anticancer activity in vitro against human leukemia cell line K562 and murine leukemia cell line L1210 in comparison with HU by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Some of the compounds showed promising anticancer activity against the cells. Molecular docking experiments with Saccharomyces cerevisiae R1 domain indicated that 4a and 4f' have stronger affinity than 4m and 4n. Flow cytometry study showed that compound 4g exerted greater apoptotic activity against K562 cells line than HU.
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Hsa-miR-1246, hsa-miR-320a and hsa-miR-196b-5p inhibitors can reduce the cytotoxicity of Ebola virus glycoprotein in vitro.
Sci China Life Sci
PUBLISHED: 08-16-2014
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Ebola virus (EBOV) causes a highly lethal hemorrhagic fever syndrome in humans and has been associated with mortality rates of up to 91% in Zaire, the most lethal strain. Though the viral envelope glycoprotein (GP) mediates widespread inflammation and cellular damage, these changes have mainly focused on alterations at the protein level, the role of microRNAs (miRNAs) in the molecular pathogenesis underlying this lethal disease is not fully understood. Here, we report that the mi-RNAs hsa-miR-1246, hsa-miR-320a and hsa-miR-196b-5p were induced in human umbilical vein endothelial cells (HUVECs) following expression of EBOV GP. Among the proteins encoded by predicted targets of these miRNAs, the adhesion-related molecules tissue factor pathway inhibitor (TFPI), dystroglycan1 (DAG1) and the caspase 8 and FADD-like apoptosis regulator (CFLAR) were significantly downregulated in EBOV GP-expressing HUVECs. Moreover, inhibition of hsa-miR-1246, hsa-miR-320a and hsa-miR-196b-5p, or overexpression of TFPI, DAG1 and CFLAR rescued the cell viability that was induced by EBOV GP. Our results provide a novel molecular basis for EBOV pathogenesis and may contribute to the development of strategies to protect against future EBOV pandemics.
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[Effects of hypergravity exposure after 30 days of simulated weightlessness on chemokine CCL20 and its receptor CCR6 in gingival tissue of rhesus macaque].
Shanghai Kou Qiang Yi Xue
PUBLISHED: 08-09-2014
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To study the effect of hypergravity exposure after 30 days of simulated weightlessness on the expression of chemokine CCL20 and its receptor CCR6 in gingival tissue of rhesus macaque.
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Nitric oxide and carbon monoxide antagonize TGF-? through ligand-independent internalization of T?R1/ALK5.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 08-06-2014
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Transforming growth factor (TGF)-? plays a central role in vascular homeostasis and in the pathology of vascular disease. There is a growing appreciation for the role of nitric oxide (NO) and carbon monoxide (CO) as highly diffusible, bioactive signaling molecules in the vasculature. We hypothesized that both NO and CO increase endocytosis of TGF-? receptor type 1 (T?R1) in vascular smooth muscle cells (VSMCs) through activation of dynamin-2, shielding cells from the effects of circulating TGF-?. In this study, primary cultures of VSMCs from Sprague-Dawley rats were treated with NO-releasing molecule 3 (a NO chemical donor), CO-releasing molecule 2 (a CO chemical donor), or control. NO and CO stimulated dynamin-2 activation in VSMCs. NO and CO promoted time- and dose-dependent endocytosis of T?R1. By decreasing T?R1 surface expression through this dynamin-2-dependent process, NO and CO diminished the effects of TGF-? on VSMCs. These findings help explain an important mechanism by which NO and CO signal in the vasculature by decreasing surface expression of T?R1 and the cellular response to TGF-?.
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Multistimuli-responsive supramolecular vesicles based on water-soluble pillar[6]arene and SAINT complexation for controllable drug release.
J. Am. Chem. Soc.
PUBLISHED: 07-17-2014
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Supramolecular binary vesicles based on the host-guest complexation of water-soluble pillar[6]arene (WP6) and SAINT molecule have been successfully constructed, which showed pH-, Ca(2+)-, and thermal-responsiveness. These supramolecular vesicles can efficiently encapsulate model substrate calcein, which then can be efficiently released either by adjusting the solution pH to acidic condition due to the complete disruption of vesicular structure, or particularly, by adding a certain amount of Ca(2+) due to the Ca(2+)-induced vesicle fusion and accompanied by the structure disruption. More importantly, drug loading and releasing experiments demonstrate that an anticancer drug, DOX, can be successfully encapsulated by the supramolecular vesicles, and the resulting DOX-loaded vesicles exhibit efficient release of the encapsulated DOX with the pH adjustment or the introduction of Ca(2+). Cytotoxicity experiments suggest that the resulting DOX-loaded supramolecular vesicles exhibit comparable therapeutic effect for cancer cells as free DOX and the remarkably reduced damage for normal cells as well. The present multistimuli-responsive supramolecular vesicles have great potential applications in the field of controlled drug delivery. In addition, giant supramolecular vesicles (~3 ?m) with large internal volume and good stability can be achieved by increasing the temperature of WP6 ? SAINT vesicular solution, and they might have potential applications for bioimaging.
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Distinct adipogenic differentiation phenotypes of human umbilical cord mesenchymal cells dependent on adipogenic conditions.
Exp. Biol. Med. (Maywood)
PUBLISHED: 06-20-2014
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The umbilical cord (UC) matrix is a source of multipotent mesenchymal stem cells (MSCs) that have adipogenic potential and thus can be a model to study adipogenesis. However, existing variability in adipocytic differentiation outcomes may be due to discrepancies in methods utilized for adipogenic differentiation. Additionally, functional characterization of UCMSCs as adipocytes has not been described. We tested the potential of three well-established adipogenic cocktails containing IBMX, dexamethasone, and insulin (MDI) plus indomethacin (MDI-I) or rosiglitazone (MDI-R) to stimulate adipocyte differentiation in UCMSCs. MDI, MDI-I, and MDI-R treatment significantly increased peroxisome proliferator-activated receptor gamma (PPAR?) and CCAAT-enhancer binding protein alpha (C/EBP?) mRNA and induced lipid droplet formation. However, MDI-I had the greatest impact on mRNA expression of PPAR?, C/EBP?, FABP4, GPD1, PLIN1, PLIN2, and ADIPOQ and lipid accumulation, whereas MDI showed the least. Interestingly, there were no treatment group differences in the amount of PPAR? protein. However, MDI-I treated cells had significantly more C/EBP? protein compared to MDI or MDI-R, suggesting that indomethacin-dependent increased C/EBP? may contribute to the adipogenesis-inducing potency of MDI-I. Additionally, bone morphogenetic protein 4 (BMP4) treatment of UCMSCs did not enhance responsiveness to MDI-induced differentiation. Finally to characterize adipocyte function, differentiated UCMSCs were stimulated with insulin and downstream signaling was assessed. Differentiated UCMSCs were responsive to insulin at two weeks but showed decreased sensitivity by five weeks following differentiation, suggesting that long-term differentiation may induce insulin resistance. Together, these data indicate that UCMSCs undergo adipogenesis when differentiated in MDI, MDI-I, and MDI-R, however the presence of indomethacin greatly enhances their adipogenic potential beyond that of rosiglitazone. Furthermore, our results suggest that insulin signaling pathways of differentiated UCMSCs are functionally similar to adipocytes.
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The oxidative molecular regulation mechanism of NOX in children with phenylketonuria.
Int. J. Dev. Neurosci.
PUBLISHED: 06-19-2014
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Phenylketonuria (PKU) is the most frequent inherited disorder of amino acid metabolism. In our previous work, we investigated the role of NADPH oxidase (NOX) in a Pahenu2-BTBR PKU mouse model, and an in vitro cell culture model of PKU. In the current study, we evaluated various oxidative stress parameters, namely total antioxidant capacity (T-AOC), glutathione (GSH) and maleic dialdehyde (MDA) in the plasma of 40 PKU children, for further investigating the oxidative molecular regulation mechanism of NOX in PKU. It was observed that T-AOC and GSH markedly decreased in PKU as compared with the control group (P<0.01), and seemed to correlate negatively with Phe level. However, there was no statistical difference in MDA level among the three groups. And 8-isoprostane in the blood samples of PKU2 groups was slightly higher than control group (P<0.05). Additionally, mRNA levels of subunits of NOX included p47(phox) and p67(phox) significantly increased in PKU group (P<0.01). These results reflected that NOX is the important source of reactive oxygen species and is involved in the oxidative molecular regulation mechanism in PKU, which shows a new perspective toward understanding the biological underpinnings of PKU.
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Gene therapy in pancreatic cancer.
World J. Gastroenterol.
PUBLISHED: 06-12-2014
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Pancreatic cancer (PC) is a highly lethal disease and notoriously difficult to treat. Only a small proportion of PC patients are eligible for surgical resection, whilst conventional chemoradiotherapy only has a modest effect with substantial toxicity. Gene therapy has become a new widely investigated therapeutic approach for PC. This article reviews the basic rationale, gene delivery methods, therapeutic targets and developments of laboratory research and clinical trials in gene therapy of PC by searching the literature published in English using the PubMed database and analyzing clinical trials registered on the Gene Therapy Clinical Trials Worldwide website (http://www. wiley.co.uk/genmed/ clinical). Viral vectors are main gene delivery tools in gene therapy of cancer, and especially, oncolytic virus shows brighter prospect due to its tumor-targeting property. Efficient therapeutic targets for gene therapy include tumor suppressor gene p53, mutant oncogene K-ras, anti-angiogenesis gene VEGFR, suicide gene HSK-TK, cytosine deaminase and cytochrome p450, multiple cytokine genes and so on. Combining different targets or combination strategies with traditional chemoradiotherapy may be a more effective approach to improve the efficacy of cancer gene therapy. Cancer gene therapy is not yet applied in clinical practice, but basic and clinical studies have demonstrated its safety and clinical benefits. Gene therapy will be a new and promising field for the treatment of PC.
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[Structural characterization and spectroscopic analysis of the aloin].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 05-15-2014
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Aloe is widely used in various fields for its rich polysaccharides, proteins, amino acids, vitamins, active enzymes and trace beneficial elements to human body. However, the main active ingredient aloin is also an allergenic ingredient, which even may cause a severe allergic reaction In this study, infrared spectroscopy, Raman spectroscopy applied to the structural characterization of the aloin Density functional theory (DFT) is applied to the theoretical calculations using the B3LYP/6-31G (d) basis set vibration, which was helpful to understand the aloin molecular vibrational frequency. By comparing we choose the optimal experimental condition for water as solvent under alkaline conditions, the detection limit of the Aloin can reach a level of 5 ppm, which can be considered the theoretical basis for rapid detection of aloin content.
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[Accumulation of myeloid-derived suppressor cells in the spleen and peripheral blood of Schistosoma japonicum-infected mice].
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi
PUBLISHED: 05-15-2014
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To determine the accumulation of CD11b+ Gr-1+ myeloid-derived suppressor cells (MDSC) in Schistosorna japonicum-infected mice.
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Identification of prognostic biomarkers in hepatitis B virus-related hepatocellular carcinoma and stratification by integrative multi-omics analysis.
J. Hepatol.
PUBLISHED: 05-08-2014
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The differentiation of distinct multifocal hepatocellular carcinoma (HCC): multicentric disease vs. intrahepatic metastases, in which the management and prognosis varies substantively, remains problematic. We aim to stratify multifocal HCC and identify novel diagnostic and prognostic biomarkers by performing whole genome and transcriptome sequencing, as part of a multi-omics strategy.
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Clinical significance of combined testing of YKL-40 with CEA in Chinese colorectal cancer patients.
Clin. Lab.
PUBLISHED: 04-05-2014
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To investigate the practical value of individual and combined testing of plasma levels of YKL-40, CEA, and CA199 for auxiliary diagnosis and detection of recurrence of colorectal cancer.
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Simultaneous solid phase extraction coupled with liquid chromatography tandem mass spectrometry and gas chromatography tandem mass spectrometry for the highly sensitive determination of 15 endocrine disrupting chemicals in seafood.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 04-04-2014
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This study aimed to develop a sensitive and reliable multi-residue method for the determination of trace amounts of endocrine disrupting chemicals including five phthalate esters (PAEs), five monoalky phthalate esters (MPEs), four alkylphenols (APs) and bisphenol A (BPA) in seafood. Ultrasonic liquid extraction was selected for extraction based on acetonitrile, instead of frequently-used n-hexane, due to its lower background of PAEs. Application of solid phase extraction (SPE) with primary secondary amine (PSA, 1g/6 mL) cartridge achieved the relatively low matrix effects for MPEs and BPA in seafood. To our knowledge, it is the first study reporting about simultaneous extraction and purification of PAEs, MPEs, APs and BPA in biota samples. To obtain the maximum sensitivity, both liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography tandem mass spectrometry (GC-MS/MS) were applied for analysis. This method was validated and tested on fish, mollusk and prawn. Sufficient linearity was verified by Mandel's fitting test for the matrix-matched calibrations used in this study for MPEs, APs and BPA, between 0.5 ng/g and 200 ng/g or 400 ng/g. And correlation coefficients of all calibrations suppressed 0.99 for all analytes. Good recoveries were obtained, ranging from 60% to 127% for most compounds. The sensitivity was good with method detection limits (MDLs) of 0.015-2.2 ng/g wet weight (ww) for all compounds. Most MDLs are much lower than those in previous reports. The sensitive method was then applied on real fish, mollusk and prawn samples from the Yangtze River Delta sea area (China), and all the target compounds were detected with the maximum concentrations of PAEs, MPEs, APs and BPA up to 219.3 ng/g ww, 51.4 ng/g ww, 62.0 ng/g ww and 8.6 ng/g ww, respectively.
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Treatment of nonconvergence of Fourier modal method arising from irregular field singularities at lossless metal-dielectric right-angle edges.
J Opt Soc Am A Opt Image Sci Vis
PUBLISHED: 04-04-2014
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In a recent work [J. Opt. Soc. Am. A28, 738 (2011)], Lifeng Li and Gerard Granet investigate nonconvergence cases of the Fourier modal method (FMM). They demonstrate that the nonconvergence is due to the irregular field singularities at lossless metal-dielectric right-angle edges. Here we make further investigations on the problem and find that the FMM surprisingly converges for deep sub-wavelength gratings (grating period being much smaller than the illumination wavelength). To overcome the nonconvergence for gratings that are not deep sub-wavelength, we approximately replace the lossless metal-dielectric right-angle edges by a medium with a gradually varied refraction index, so as to remove the irregular field singularities. With such treatment, convergence is observed as the region of the approximate medium approaches vanishing.
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Clinical characteristics and current management of hepatitis B and C in China.
World J. Gastroenterol.
PUBLISHED: 03-24-2014
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To describe a population of outpatients in China infected by hepatitis B virus (HBV) and/or hepatitis C virus (HCV), and assess their current management status.
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Thiosemicarbazone Cu(II) and Zn(II) complexes as potential anticancer agents: syntheses, crystal structure, DNA cleavage, cytotoxicity and apoptosis induction activity.
J. Inorg. Biochem.
PUBLISHED: 03-09-2014
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Four novel thiosemicarbazone metal complexes, [Cu(Am4M)(OAc)]·H2O (1), [Zn(HAm4M)Cl2] (2), [Zn2(Am4M)2Br2] (3) and [Zn2(Am4M)2(OAc)2]·2MeOH (4) [HAm4M=(Z)-2-(amino(pyridin-2-yl)methylene)-N-methylhydrazinecarbothioamide], have been synthesized and characterized by X-ray crystallography, elemental analysis, ESI-MS and IR. X-ray analysis revealed that complexes 1 and 2 are mononuclear, which possess residual coordination sites for Cu(II) ion in 1 and good leaving groups (Cl(-)) for Zn(II) ion in 2. Both 3 and 4 displayed dinuclear units, in which the metal atoms are doubly bridged by S atoms of two Am4M(-) ligands in 3 and by two acetate ions in bi- and mono-dentate forms, respectively, in 4. Their antiproliferative activities on human epithelial cervical cancer cell line (HeLa), human liver hepatocellular carcinoma cell line (HepG-2) and human gastric cancer cell line (SGC-7901) were screened. Inspiringly, IC50 value (11.2±0.9 ?M) of complex 1 against HepG-2 cells was nearly 0.5 fold of that against human hepatic cell lines LO2, showing a lower toxicity to human liver cells. Additionally, it displayed a stronger inhibition on the viability of HepG-2 cells than cisplatin (IC50=25±3.1 ?M), suggesting complex 1 might be a potential high efficient antitumor agent. Furthermore, fluorescence microscopic observation and flow cytometric analysis revealed that complex 1 could significantly suppress HepG-2 cell viability and induce apoptosis. Several indexes, such as DNA cleavage, reactive oxygen species (ROS) generation, comet assay and cell cycle analysis indicated that the antitumor mechanism of complex 1 on HepG-2 cells might be via ROS-triggered apoptosis pathway.
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Growth-associated protein 43 and progressive epilepsy in cortical dysplasia.
Ann Clin Transl Neurol
PUBLISHED: 02-24-2014
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To investigate growth-associated protein 43 (GAP-43), a marker for axonal growth and synaptic plasticity, as potential substrate for progressive epilepsy and potential predictor of postsurgical seizure outcome in patients with focal cortical dysplasia (FCD).
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Perioperative Pregabalin for Acute Pain After Gynecological Surgery: A Meta-analysis.
Clin Ther
PUBLISHED: 02-16-2014
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Pregabalin has been used as an adjuvant in some trials to control postoperative pain after gynecologic surgery. However, the potential clinical advantage remains debatable.
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Overexpression of DEK gene is correlated with poor prognosis in hepatocellular carcinoma.
Mol Med Rep
PUBLISHED: 02-12-2014
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The oncogene DEK was originally identified as one of the parts of the DEK?CAN fusion gene, arising from the translocation (6;9) in a subtype of acute myeloid leukemia. Since then, DEK has been shown to promote tumorigenesis in a variety of cancer cell types through its roles in inhibiting cell differentiation, senescence and apoptosis. Certain studies have established that DEK is dysregulated in several types of cancer, including hepatocellular carcinoma (HCC). However, its clinical significance in human HCC remains unknown. In this study, the expression of DEK mRNA and protein was examined in 55 surgical HCC specimens and matched non?tumorous tissues. In addition, the correlation between DEK expression and clinicopathological characteristics and prognosis was analyzed. mRNA and protein levels of DEK were found to be significantly overexpressed in the majority of HCC tumors when compared with matched normal hepatic tissues (P<0.05). In addition, the expression pattern of DEK was closely correlated with differentiation status, portal venous invasion and tumor size (P<0.05). Kaplan?Meier curves demonstrated that patients with higher DEK expression levels had significantly poorer survival than those with lower DEK expression levels (P=0.003). In addition, Cox regression analysis demonstrated that the level of DEK expression may be a valuable prognostic factor (P<0.05). These results suggested that DEK may play a significant role in hepatocyte differentiation and may serve as a useful prognostic marker and biomarker for the staging of HCC.
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The isotopic effects of deuteration on optoelectronic properties of conducting polymers.
Nat Commun
PUBLISHED: 01-25-2014
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The attractive optoelectronic properties of conducting polymers depend sensitively upon intra- and inter-polymer chain interactions, and therefore new methods to manipulate these interactions are continually being pursued. Here, we report a study of the isotopic effects of deuterium substitution on the structure, morphology and optoelectronic properties of regioregular poly(3-hexylthiophene)s with an approach that combines the synthesis of deuterated materials, optoelectronic properties measurements, theoretical simulation and neutron scattering. Selective substitutions of deuterium on the backbone or side-chains of poly(3-hexylthiophene)s result in distinct optoelectronic responses in poly(3-hexylthiophene)/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) photovoltaics. Specifically, the weak non-covalent intermolecular interactions induced by the main-chain deuteration are shown to change the film crystallinity and morphology of the active layer, consequently reducing the short-circuit current. However, side-chain deuteration does not significantly modify the film morphology but causes a decreased electronic coupling, the formation of a charge transfer state, and increased electron-phonon coupling, leading to a remarkable reduction in the open circuit voltage.
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ALDH1 is a better clinical indicator for relapse of invasive ductal breast cancer than the CD44+/CD24- phenotype.
Med. Oncol.
PUBLISHED: 01-23-2014
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Breast cancer stem cells are thought to be associated with metastasis and poor prognosis, but their clinical importance remains poorly understood. The aim of this study was to investigate whether certain phenotypes of breast cancer stem cells were clinically important factors regarding metastasis. Patients with primary breast cancer (n=121) were included in this study. Breast cancer stem cells were identified by immunohistochemical staining of CD44, CD24, and aldehyde dehydrogenase 1 (ALDH1) in tumor tissues from primary and recurrent or metastatic lesions. CD44+/CD24- cells and ALDH1+ cells were considered breast cancer stem cells. Sixty-five patients had metastatic or recurrent tumors. ALDH1+ tumors were significantly associated with a high rate of metastasis or recurrence (63.1%; P=0.026). Although there was no significant association between the proportion of CD44+/CD24- tumor cells and metastasis rates, a high proportion of CD44+/CD24- tumor cells was a risk factor for metastasis or recurrence (P=0.035). Changes in the proportion of CD44+/CD24- or ALDH1+ tumor cells between primary lesions and recurrent lesions were studied in 27 patients. The proportion of ALDH1+ tumor cells increased significantly (P=0.019) after recurrence, but the proportion of CD44+/CD24- tumor cells did not. Our findings suggest that ALDH1+ and CD44+/CD24- breast cancer stem cells play significant roles in metastasis. The rate of ALDH1+ cells appears to be a better predictive marker of breast cancer metastasis than the CD44+/CD24- phenotype.
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Effects of azathioprine and infliximab on mesenchymal stem cells derived from the bone marrow of rats in vitro.
Mol Med Rep
PUBLISHED: 01-14-2014
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Mesenchymal stem cell (MSC) transplantation has been demonstrated to be promising in the treatment of inflammatory bowel disease (IBD). Azathioprine (AZA) is widely used in IBD patients. Infliximab, as a representative of biological therapy for IBD, is important in the treatment regimen. In the present study we investigated the effects of AZA and infliximab on the cell proliferation, cell cycle and apoptosis of the MSCs derived from the bone marrow of Sprague?Dawley (SD) rats in vitro in order to provide preliminary data for optimizing the treatment of IBD. MSCs derived from the bone marrow of rats were either cultured in various concentrations of AZA? or infliximab?supplemented medium for 24, 48 and 72 h, respectively. The growth curves of MSCs were obtained. The apoptosis and the cell cycle of the MSCs were analyzed by flow cytometry. AZA decreased the proliferation of MSCs by 66% and increased apoptosis at 0.20 mg/ml for 72 h (P<0.05). The percentage of necrotic cells increased markedly in MSCs treated with 0.30 mg/ml AZA for 72 h (P<0.05). As the exposure time increased, the percentage of MSCs in phase G0?G1 increased and that in phase S decreased in AZA groups exceeding 0.20 mg/ml (P<0.05). However, infliximab had a minimal impact on the cell proliferation, apoptosis and cell cycle of the MSCs. AZA was able to inhibit cell proliferation and induce apoptosis of the MSCs in vitro. Infliximab did not affect the cell proliferation, apoptosis and cell cycle of the MSCs derived from rats.
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[Progress in researches on the sperm centrosome].
Zhonghua Nan Ke Xue
PUBLISHED: 12-18-2013
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In humans and most mammals, the sperm centrosome is primarily responsible for nucleating and organizing the sperm astar, which pushes the sperm head toward the oocyte center and guides the migration of the female pronucleus, completing the fertilization process. There are about 200 kinds of protein in the human sperm centrosome. Currently, most of the researches focus on the centrin protein. Further studies on the functions of different human sperm centrosomal proteins may contribute to the understanding of the causes of the failures in assisted reproductive technology (ART). And in ART, morphological observation of the sperm neck integrity is the only way for primary evaluation of the function of the sperm centrosome.
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Vesicular phospholipid gels using low concentrations of phospholipids for the sustained release of thymopentin: pharmacokinetics and pharmacodynamics.
Pharmazie
PUBLISHED: 11-27-2013
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Vesicular phospholipid gels (VPGs) with high concentrations of phospholipids are used as implantable depots for sustained release of drugs due to high viscosity. This study aimed to investigate VPGs with low concentrations of phospholipids for subcutaneous injection and sustained release in vivo. A small peptide, thymopentin, was selected and incorporated into various VPG formulations. The VPG viscosity was greatly increased with higher concentrations of phospholipids (E80) and thus VPGs based on low lipid contents are more suitable for injection. Additionally, VPGs loaded with 5-hydroxy-fluorescein-thymopetin (5-FAM-TP5-VPGs) were developed and their pharmacokinetic profile was investigated in vivo. After subcutaneous injection, the release time of 5-FAM-TP5 was 216 h for 5-FAM-TP5-VPGs (containing 300 mg/g lipid), which was much longer than that of 5-FAM-TP5 solution. The therapeutic efficacy of TP5-VPGs (containing 300 mg/g lipid) after subcutaneous administration once a week was demonstrated to be comparable to that of TP5 solution injected subcutaneously once daily for 7 days. In conclusion, TP5-VPGs with low lipid content (300 mg/g) displayed sustained release properties in vivo that may serve as a sustained delivery system for subcutaneous injection.
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IL-35: a potential target for the treatment of atherosclerosis.
Pharmazie
PUBLISHED: 11-27-2013
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The imbalance of anti- inflammatory/pro-inflammatory cytokines plays an important role in the process of atherosclerosis. IL-35 is an anti-inflammatory cytokine comprising the p35 subunit of IL-12 and the subunit Epstein-Barr virus (EBV) -induced gene 3(EBI3). Accumulating evidence showed that IL-35 up-regulates the expression of anti-inflammatory cytokines, induces the generation of CD4 + regulatory T cells, inhibits CD4 + effector T cells response and other target cells activity, and reduces the progression of inflammatory and autoimmune diseases. In addition, it has been found that Ebi3 and p35 strongly coexpressed in human advanced lesions. Therefore, we hypothesize that IL-35 may become a novel target for the treatment of atherosclerosis. Further studies are required to investigate the precise effect and the signaling pathway of IL-35 in atherosclerosis process.
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[Effect of different altitudes on telomere length of rat peripheral blood leukocyte].
Sheng Li Xue Bao
PUBLISHED: 10-17-2013
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The present study was aimed to investigate the effect of different altitudes on telomere length of rat peripheral blood leukocyte and possible mechanism. Sixty male rats were randomly divided into three groups, lower altitude control group (10 m), moderate altitude group (2 260 m) and very high altitude group (simulated 5 000 m). The moderate altitude group and very high altitude group rats were transported to Xining and hypobaric chamber in Qinghai University, respectively. The peripheral blood specimens were extracted 30 d after the transportation. By means of real-time PCR, automatic blood cell analyzer, ELISA, TBA and WST-1 methods, the telomere lengths of blood leukocyte, the hemoglobin (Hb) contents, the plasma levels of telomerase reverse transcriptase (TERT) and hypoxia-inducible factor 1? (HIF-1?), the plasma content of malondialdehyde (MDA) and superoxide dismutase (SOD) activity were measured, respectively. The results showed that the telomere lengths of peripheral blood leukocyte in moderate altitude group were longer than those in control group and very high altitude group. The changes of TERT were compatible with the telomere length of peripheral blood leukocyte under different altitudes. The levels of HIF-1? in moderate altitude group and very high altitude group were higher than that of control group. The very high altitude group showed decreased SOD activities and increased level of MDA, compared with the other two groups. These results suggest that the telomere lengths of rat peripheral blood leukocyte in moderate altitude are elongated, and that the telomere-elongating effect is lost under very high altitude. The changes of HIF-1?, TERT and oxidative stress damage are the main mechanisms of telomere length changes. Moderate altitude living might be beneficial to increasing the life span in mammals.
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Excision repair cross-complementation group 1 codon 118 polymorphism, micro ribonucleic acid and protein expression, clinical outcome of the advanced gastric cancer response to first-line FOLFOX-4 in Qinghai-Tibetan plateau population.
J Cancer Res Ther
PUBLISHED: 10-16-2013
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The excision repair cross-complementation group 1 (ERCC1) codon 118 C/T polymorphism has been associated with clinical outcome in cancer patients treated with platinum chemotherapy. Ethnic differences in the frequency of this polymorphism have been observed in Caucasian and African populations.
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Large-area electromagnetic enhancement by a resonant excitation of surface waves on a metallic surface with periodic subwavelength patterns.
Opt Express
PUBLISHED: 10-10-2013
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We theoretically investigate the electromagnetic enhancement on a metallic surface patterned with periodic subwavelength structures. Fully-vectorial calculations show a large-area electromagnetic enhancement (LAEE) on the surface, which strongly contrasts with the previously reported "hot spots" that occur in specific tiny regions and which relieves the rigorous requirement of the nano-scale location of sample molecules. The LAEE allows for designing more practicable substrates for many enhanced-spectra applications. By building up microscopic models, the LAEE is shown due to a resonant excitation of surface waves that include both the surface plasmon polariton (SPP) and a quasi-cylindrical wave (QCW). The surface waves propagate on the substrate over a long distance and thus greatly enlarge the area of electromagnetic enhancement compared to the nano-sized hot spots caused by localized modes. Gain medium is introduced to further strengthen the large-area surface-wave resonance, with which an enhancement factor (EF) of electric-field intensity up to a few thousands is achieved.
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Downregulation of CD4+LAP+ and CD4+CD25+ Regulatory T Cells in Acute Coronary Syndromes.
Mediators Inflamm.
PUBLISHED: 10-05-2013
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Background. Regulatory T (Treg) cells play a protective role in atherosclerosis prone models and are related to the onset of acute coronary syndromes (ACS, including non-ST-elevation ACS (NSTEACS) and ST-elevation acute myocardial infarction (STEAMI)). CD4+LAP+ Treg cells are a novel subset of Tregs that have been found to ameliorate atherosclerosis in ApoE(-/-) mice, and these cells also exist in humans. The present study was designed to investigate whether CD4+LAP+ Treg cells are involved in the onset of ACS. Methods. The frequencies of CD4+LAP+ and CD4+CD25+ Treg cells were detected using flow cytometric analysis, and the plasma IL-10 and TGF- ? 1 levels were measured using an ELISA in 29 stable angina (SA) patients, 30 NSTEACS patients, 27 STEAMI patients, and a control group (30 cases). Results. The results revealed a significant decrease in the frequencies of CD4+LAP+ and CD4+CD25+ Treg cells and in the levels of IL-10 and TGF- ? 1 in patients with ACS compared with those in the SA and control groups. Conclusions. The decrease in the frequencies of CD4+LAP+ and CD4+CD25+ Treg cells may play a role in the onset of ACS.
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Biological evaluation of a cytotoxic 2-substituted benzimidazole copper(II) complex: DNA damage, antiproliferation and apoptotic induction activity in human cervical cancer cells.
Biometals
PUBLISHED: 09-29-2013
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Exploring novel chemotherapeutic agents is a great challenge in cancer medicine. To that end, 2-substituted benzimidazole copper(II) complex, [Cu(BMA)Cl2]·(CH3OH) (1) [BMA = N,N-bis(benzimidazol-2-yl-methyl)amine], was synthesized and its cytotoxicity was characterized. The interaction between complex 1 and calf thymus DNA was detected by spectroscopy methods. The binding constant (K b = 1.24 × 10(4 )M(-1)) and the apparent binding constant (K app = 6.67 × 10(6 )M(-1)) of 1 indicated its moderate DNA affinity. Complex 1 induced single strand breaks of pUC19 plasmid DNA in the presence of H2O2 through an oxidative pathway. Cytotoxicity studies proved that complex 1 could inhibit the proliferation of human cervical carcinoma cell line HeLa in both time- and dose-dependent manners. The results of nuclei staining by Hoechst 33342 and alkaline single-cell gel electrophoresis proved that complex 1 caused cellular DNA damage in HeLa cells. Furthermore, treatment of HeLa cells with 1 resulted in S-phase arrest, loss of mitochondrial potential, and up-regulation of caspase-3 and -9 in HeLa cells, suggesting that complex 1 was capable of inducing apoptosis in cancer cells through the intrinsic mitochondrial pathway.
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Maternal obesity enhances white adipose tissue differentiation and alters genome-scale DNA methylation in male rat offspring.
Endocrinology
PUBLISHED: 08-19-2013
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The risk of obesity (OB) in adulthood is strongly influenced by maternal body composition. Here we examined the hypothesis that maternal OB influences white adipose tissue (WAT) transcriptome and increases propensity for adipogenesis in the offspring, prior to the development of OB, using an established model of long-term metabolic programming. Employing an overfeeding-based rat model, in which exposure to OB is limited to preconception and gestation alone, we conducted global transcriptomic profiling in WAT, and gene/protein expression analysis of lipogenic and adipogenic pathways and examined adipogenic differentiation of WAT stromal-vascular cells ex vivo. Using reduced representation bisulfite sequencing we also evaluated genome-scale changes in DNA methylation in offspring WAT. Maternal OB led to extensive changes in expression of genes (± 1.8-fold, P ? .05), revealing a distinct up-regulation of lipogenic pathways in WAT. mRNA expression of a battery of sterol regulatory element-binding protein-1-regulated genes was increased in OB-dam offspring, which were confirmed by immunoblotting. In conjunction with lipogenic gene expression, OB-dam offspring showed increased glucose transporter-4 mRNA/protein expression and greater AKT phosphorylation following acute insulin challenge, suggesting sensitization of insulin signaling in WAT. Offspring of OB dams also exhibited increased in vivo expression of adipogenic regulators (peroxisome proliferator-activated receptor-?, CCAAT enhancer binding protein ? [C/EBP-?] and C/EBP-?), associated with greater ex vivo differentiation of WAT stromal-vascular cells. These transcriptomic changes were associated with alterations in DNA methylation of CpG sites and CGI shores, proximal to developmentally important genes, including key pro-adipogenic factors (Zfp423 and C/EBP-?). Our findings strongly suggest that the maternal OB in utero alters adipocyte commitment and differentiation via epigenetic mechanisms.
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N,N-Diethyl-4-[1-phenyl-3-(pyridin-2-yl)-4,5-di-hydro-1H-pyrazol-5-yl]aniline.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 08-01-2013
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In the title mol-ecule, C24H26N4, the pyrazoline ring assumes an envelope conformation with the aniline-bearing C atom at the flap position. The benzene ring and the pyridine ring form with the pyrazoline ring dihedral angles of 4.53?(1) and 6.26?(1)°, respectively. In turn, the aniline group is nearly perpendicular to the pyrazoline ring [dihedral angle = 79.96?(1)°]. The ethyl groups of the di-ethyl-amine substituent are disordered over two sets of sites, with an occupancy ratio of 0.624?(8):0.376?(8).
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Epigenetic silencing of glutaminase 2 in human liver and colon cancers.
BMC Cancer
PUBLISHED: 07-15-2013
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Glutaminase 2 (Gls2) is a p53 target gene and is known to play an important role in energy metabolism. Gls2 has been reported to be downregulated in human hepatocellular carcinomas (HCC). However, the underlying mechanism responsible for its downregulation is still unclear. Here, we investigated Gls2 expression and its promoter methylation status in human liver and colon cancers.
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Synthesis, characterization, cytotoxicity and antibacterial activity of an anthracenyl-linked bis(pyrazolyl)methane ligand and its zinc(II) complexes.
Eur J Med Chem
PUBLISHED: 07-08-2013
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Three novel Zn(II) complexes (1-3) with 1,1-(anthracen-9-ylmethylene)bis(1H-pyrazole) (L(2)) have been prepared and structurally characterized by X-ray crystallography. Among them, 1 is a binuclear Zn(II) complex while 2 and 3 are mononuclear. The in vitro cytotoxic and antibacterial activities of these complexes were also evaluated. The three complexes exhibit cytotoxic specificity and significant antitumor activity. The MIC50 value of complex 1 against Pseudomonas putida reaching 0.011 ?g/mL much lower than that the positive control chloromycin (0.182 ?g/mL), indicates that complex 1 is a potent antibacterial agent.
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Striking life events associated with primary breast cancer susceptibility in women: a meta-analysis study.
J. Exp. Clin. Cancer Res.
PUBLISHED: 07-01-2013
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The association between striking life events, an important stress and acute anxiety disorder, and the occurrence of primary breast cancer is unclear. The current meta-analysis was designed to assess the relationship between striking life events and primary breast cancer incidence in women.
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Antiproliferative triterpenoid saponins from the stem of Psychotria sp.
Planta Med.
PUBLISHED: 06-26-2013
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Six new triterpenoid saponins, psychotrianosides A-F (1-6), and two known triterpenoid saponins, psychotrianoside G (7) and ardisianoside D (8), were isolated from Psychotria sp. Their structures were determined mainly by spectroscopic methods. The cytotoxic activities of 1-8 against five human cancer cell lines (MDA-MB-231, MCF-7, MCF-7/ADM, HepG2, and HepG2/ADM) are reported for the first time. Psychotrianoside C (3) showed the most potent antiproliferative activity among these saponins, and the IC50 value of 3 against MDA-MB-231 was 2.391 ± 0.161 µM. Compound 3 was also found to induce apoptosis.
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Endothelial PAS domain protein 1 Chr2:46441523(hg18) polymorphism is associated with susceptibility to high altitude pulmonary edema in Han Chinese.
Wilderness Environ Med
PUBLISHED: 05-23-2013
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The purpose of this study was to test the hypothesis that polymorphisms in the endothelial PAS domain protein 1 (EPAS1) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Han Chinese.
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Early growth response protein-1 mediates lipotoxicity-associated placental inflammation: role in maternal obesity.
Am. J. Physiol. Endocrinol. Metab.
PUBLISHED: 04-30-2013
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Obesity is associated with low-grade chronic inflammation, which contributes to cellular dysfunction promoting metabolic disease. Obesity during pregnancy leads to a proinflammatory milieu in the placenta; however, the underlying causes for obesity-induced placental inflammation remain unclear. Here, we examine the mechanisms by which saturated fatty acids and inflammatory cytokines induce inflammation in placental trophoblasts. We conducted global transcriptomic profiling in BeWo cells following palmitate and/or TNF? treatment and gene/protein expression analyses of MAPK pathways and characterized downstream transcription factors directly regulating inflammatory cytokines. Microarray analysis revealed increased expression of genes regulating inflammation, stress response, and immediate early response in cytotrophoblasts in response to palmitic acid (PA), TNF?, or a combination of both (PA + TNF?). Both gene ontology and gene set enrichment analysis revealed MAPK and EGR-1 signaling to be upregulated in BeWo cells, which was confirmed via immunoblotting. Importantly, activation of JNK signaling was necessary for increased proinflammatory cytokine (IL-6, TNF?, and IL-8) and EGR1 mRNA. Consistent with the requirement of JNK signaling, ChIP analysis confirmed the recruitment of c-Jun and other MAPK-responsive immediate early factors on the EGR1 promoter. Moreover, recruitment of EGR-1 on cytokine promoters (IL-6, TNF?, and IL-8) and an impaired proinflammatory response following knockdown of EGR-1 suggested it as a central component of the mechanism facilitating inflammatory gene expression. Finally, akin to in vitro findings, term placenta from obese women also had both increased JNK and p38 signaling and greater EGR-1 protein relative to lean women. Our results demonstrate that lipotoxic insults induce inflammation in placental cells via activation of JNK/EGR-1 signaling.
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Synthesis, electrochemistry, and photophysics of a family of phlorin macrocycles that display cooperative fluoride binding.
J. Am. Chem. Soc.
PUBLISHED: 04-17-2013
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A homologous set of 5,5-dimethylphlorin macrocycles in which the identity of one aryl ring is systematically varied has been prepared. These derivatives contain ancillary pentafluorophenyl (3H(Phl(F))), mesityl (3H(Phl(Mes))), 2,6-bismethoxyphenyl (3H(Phl(OMe))), 4-nitrophenyl (3H(Phl(NO2))), or 4-tert-butylcarboxyphenyl (3H(Phl(CO2tBu))) groups at the 15-meso-position. These porphyrinoids were prepared in good yields (35-50%) and display unusual multielectron redox and photochemical properties. Each phlorin can be oxidized up to three times at modest potentials and can be reduced twice. The electron-donating and electron-releasing properties of the ancillary aryl substituent attenuate the potentials of these redox events; phlorins containing electron-donating aryl groups are easier to oxidize and harder to reduce, while the opposite trend is observed for phlorins containing electron-withdrawing functionalities. Phlorin substitution also has a pronounced effect on the observed photophysics, as introduction of electron-releasing aryl groups on the periphery of the macrocycle is manifest in larger emission quantum yields and longer fluorescence lifetimes. Each phlorin displays an intriguing supramolecular chemistry and can bind 2 equiv of fluoride. This binding is allosteric in nature, and the strength of halide binding correlates with the ability of the phlorin to stabilize the buildup of charge. Moreover, fluoride binding to generate complexes of the form 3H(Phl(R))·2F(-) modulates the redox potentials of the parent phlorin. As such, titration of phlorin with a source of fluoride represents a facile method to tune the ability of this class of porphyrinoid to absorb light and engage in redox chemistry.
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Evaluation of reproductive and developmental toxicities of Pu-erh black tea (Camellia sinensis var. assamica) extract in Sprague Dawley rats.
J Ethnopharmacol
PUBLISHED: 03-18-2013
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Pu-erh black tea, which is obtained by first parching crude green tea leaves and followed by secondary fermentation with microorganisms, has been believed to be beneficial beverages for health in PR China. But its potential toxicity when administered at a high dose as concentrated extract has not been completely investigated.
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Role of surface plasmon polaritons and photonic modes in light absorption by thin-film solar cells patterned with metallic nanogratings.
Opt Lett
PUBLISHED: 03-05-2013
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Light absorption by thin-?lm amorphous Si solar cells patterned with metallic nanogratings is investigated theoretically. Propagative bounded modes that include the surface plasmon polariton (SPP) and the photonic mode (PM) are extracted from the total field to quantitatively evaluate their contribution to the light absorption. Our results show that after removing the propagative bounded modes from the total field, the residual field still contributes to a major part of the total light absorption. This proves, at a quantitative level, that the light absorption of the structure is largely attributed to the residual field that is composed of unbounded or evanescent modes arising from the grating scattering, and the SPP and the PM do not play a dominant role, which is out of the previous intuitive expectations.
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Antiviral effects of modified dingchuan decoction against respiratory syncytial virus infection in vitro and in an immunosuppressive mouse model.
J Ethnopharmacol
PUBLISHED: 02-25-2013
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Modified dingchuan decoction (MDD) is used in traditional Chinese medicine for the treatment of cough, chronic bronchitis, asthma and viral pneumonia.
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Surveillance on the status of immune cells after Echinnococcus granulosus protoscoleces infection in Balb/c mice.
PLoS ONE
PUBLISHED: 02-17-2013
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Cystic echinococcosis is a global parasitic disease caused by infection with Echinococcus granulosus larvae with potentially life-threatening complications in humans. To date, the status of the immune cells believed to be associated with the pathogenicity of E. granulosus infection has not been demonstrated clearly.
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A randomized controlled trial to evaluate the relative efficacy of the addition of a psycho-social intervention to standard-of-care services in reducing attrition and improving attendance among first-time users of methadone maintenance treatment in China.
AIDS Behav
PUBLISHED: 02-16-2013
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Although methadone maintenance treatment (MMT) is an important means of HIV control, MMT clinics commonly have high attrition rates. The randomized controlled trial investigated the relative efficacy of adding a psycho-social intervention to the standard-of-care MMT in reducing attrition and non-attendance among first-time newly admitted MMT users in China (n = 288). Social workers implemented this three-phase intervention that was based on a behavioral maintenance theory. It also involved participants family members and rectified some MMT-related misconceptions. As compared to the control group, the intervention group showed significantly lower likelihood of attrition (HR = 0.55, 95% confidence interval 0.39-0.80), lower estimated probability of attrition at Month 12 (0.35 vs. 0.55), and higher median number of days of attendance (Month 6: 147 vs. 91 days, p < 0.001; end-date: 225 vs. 142 days, p < 0.001). Further psycho-social services and translational research are warranted.
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Expression of ALDH1 in breast invasive ductal carcinoma: an independent predictor of early tumor relapse.
Cancer Cell Int.
PUBLISHED: 02-06-2013
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The specific mechanism underlying the contribution of the Aldehyde dehydrogenase 1 (ALDH1) phenotype to metastatic behavior and early tumor relapse in breast cancer is currently unclear.
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Relationship between LTR methylation and gag expression of HIV-1 in human spermatozoa and sperm-derived embryos.
PLoS ONE
PUBLISHED: 01-28-2013
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Studying the methylation status of long terminal repeats (LTR) and its relationship to gag expression of HIV-1 in order to explore regulation mechanism of HIV-1 gene expression in vertical transmission from sperm to embryo.
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Atmospheric depositional fluxes and sources apportionment of organochlorine pesticides in the Pearl River Delta region, South China.
Environ Monit Assess
PUBLISHED: 01-19-2013
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Organochlorine pesticides (OCPs) have variously been phased out in agricultural activities, but they are still widely detected in air, water, and soil systems due to their recalcitrant nature in the environment. The purposes of this study were to assess potential OCP pollution via dry and wet deposition over the fast developing Pearl River Delta area with 41,700 km(2), where the main effort has been focused on emerging pollutants such as petroleum hydrocarbons and PM2.5. We quantified both the dry and wet deposition fluxes of 19 OCPs including dichlorodiphenyltrichloroethanes (DDTs), endosulfans (Endos), and hexachlorocyclohexanes (HCHs). The results showed that each year about 67.4, 42.0, 15.0, and 8.07 kg of total OCPs, DDTs, Endos, and HCHs were returned to the ground, among which 11.7, 10.4, 0.84, and 0.16 kg were in the dry deposition forms. The large spatial variations in OCP deposition fluxes indicated that OCP pollution in the air is mainly influenced on local scales because evaporation from local soil is likely the major source of the phased out OCPs. Source analysis indicated that DDTs may be still in use as antifouling agent and/or dicofol, but Endos and HCHs were mainly derived from the residual of historical usage. The study suggests that the historical OCP pollutants are persistent at high levels in this area and should not be overlooked, while we tackle emerging pollutants.
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Hypolipidemic and antioxidant activities of polysaccharides from Rosae Laevigatae Fructus in rats.
Carbohydr Polym
PUBLISHED: 01-02-2013
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Two major fractions (RLP-1 and RLP-2) were obtained by purifying the crude polysaccharides extracted from a traditional Chinese herb Rosae Laevigatae Fructus. The average molecular weight of RLP-1 and RLP-2 was 21.5 kDa and 16.1 kDa, respectively. Monosaccharide analysis indicated that RLP-1 was composed of xylose, mannose and galactose in the molar ratio of 1:11:8, while RLP-2 was only a glucan. Oral administration of RLP-1 could significantly decrease levels of serum total cholesterol (TC), triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C), inhibit hepatic lipid accumulation, increase antioxidant lipids and up-regulate expressions of peroxisome proliferator-activated receptor-? (PPAR-?) and lipoprotein lipase (LPL) in hyperlipidemia rats. These results suggest that RLP-1 improve hyperlipidemia possibly through regulating PPAR-mediated lipid metabolism. Therefore, could be explored as a possible agent for hyperlipidemia.
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Hepatitis B virus s protein enhances sperm apoptosis and reduces sperm fertilizing capacity in vitro.
PLoS ONE
PUBLISHED: 01-01-2013
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Studying the impact of Hepatitis B virus S protein (HBs) on early apoptotic events in human spermatozoa and sperm fertilizing capacity.
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[Genetic cloning and expression of hypoxia inducible factor 1 alpha in high altitude hypoxic adaptation species Tibetan antelope (Pantholops hodgsonii)].
Sheng Li Xue Bao
PUBLISHED: 12-24-2011
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In order to investigate the role of the hypoxia inducible factor 1 alpha (HIF-1?) in the adaptation mechanism to high altitude hypoxia, the cloning of the HIF-1? gene cDNA of Tibetan antelope (Pantholops hodgsonii), using RT-PCR and RACE, was applied, and the comparative analysis of the tissue-specific expressions of HIF-1? among Tibetan antelope, Tibetan sheep and plain sheep was performed using real-time PCR and Western blot. The sequence analysis indicated that the cDNA sequences acquired by cloning from the HIF-1? gene of Tibetan antelope comprised a 2 471-bp open reading frame (ORF) and a 1 911-bp 3UTR. The similarity between its coding sequence, predicted amino acid sequence and HIF-1? of other mammals exceeded 87%, in which the similarity with cow was up to more than 98%, which showed that this sequence was the cDNA of HIF-1? of Tibetan antelope. The results of real-time PCR and Western blot showed that expressions of HIF-1? mRNA and protein appeared in Tibetan antelopes lung, cardiac muscle and skeletal muscle, with the highest expression in lung. HIF-1? mRNA and protein had obvious differential expression in these tissues. Further research showed that Tibetan antelope and Tibetan sheep possessed higher expressions of HIF-1? protein in the three tissues above-mentioned compared with plain sheep, and the expressions of HIF-1? mRNA and protein in Tibetan antelopes lung, cardiac muscle and skeletal muscle were higher than those of Tibetan sheep. It illustrates that the hypoxic HIF-1?-specific expression is one of the molecular bases of high altitude hypoxia adaptation in Tibetan antelope.
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[Circulating microRNA-92a in patients with ST-segment elevation myocardial infarction].
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 12-14-2011
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To examine the expression of circulating microRNA-92a (miR-92a) in patients with ST-segment elevation myocardial infarction (STEMI), and the impact of percutaneous coronary intervention (PCI) on such expression.
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Antioxidant behavior in bulk oil: limitations of polar paradox theory.
J. Agric. Food Chem.
PUBLISHED: 12-08-2011
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The polar paradox theory that explains the efficacy of antioxidants as affected by their polarity and that of the medium involved was re-evaluated. For the first time, the effect of concentration on validity of the polar paradox theory was investigated using four pairs of polar and nonpolar representative antioxidants in bulk oil. A model on antioxidant behavior in response to their polarity is proposed.
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[Analysis on the occupational poisoning case of trichloroethylene reported in Dongguan during 2002 to 2009 ].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 12-05-2011
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To understand the demographic, occupational and clinic characteristics of occupational poisoning case due to trichloroethylene in Dongguan in recent years for the purpose of prevention.
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Critical role of CD40-mediated autocrine tumor necrosis factor-alpha in potentiation of cisplatin-induced cytotoxicity in cancer cells.
Cancer Sci.
PUBLISHED: 11-17-2011
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Activation of CD40, a member of the tumor necrosis factor receptor (TNF-R) family, results in growth inhibition or apoptosis in some tumor cells, making CD40 a potential antitumor therapeutic target. Although it is known that CD40 is able to induce tumor necrosis factor-alpha (TNF-?) secretion and potentiate cisplatins anticancer activity, whether TNF-? induction is involved in sensitizing cisplatin by CD40 has not been addressed. In this report, we provide evidence substantiating an important role of autocrine TNF-? in potentiation of cisplatin-induced apoptosis by recombinant soluble CD40 ligand (rsCD40L) in different human cancer cell lines. Activation of CD40 by rsCD40L induces two phases of autocrine TNF-?: the rapid early phase involving p38 MAP kinase and the robust and persistent late phase through enhanced tnf-? gene transcription. Blocking TNF-? with either a specific TNFR1 siRNA or a neutralizing anti-TNF-? antibody dramatically attenuated the potentiation effect of rsCD40L on cisplatin-induced cancer cell death. These results reveal an important role of TNF-? induction in CD40s chemosensitization activity and suggest that modulating TNF-? autocrine from cancer cells is an effective option for increasing the anticancer value of chemotherapeutics such as cisplatin.
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New sphingolipid psychotramide A-D from the stem of Psychotria sp.
Nat. Prod. Res.
PUBLISHED: 10-19-2011
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Chemical study of the Psychotria sp. led to the isolation of a new type of ceramide named psychotramide (1). HR-FAB-MS analysis revealed that psychotramide consists of four new sphingolipids. Their structures were determined on the basis of the spectroscopic data and chemical methods to be psychotramide A (1-a), psychotramide B (1-b), psychotramide C (1-c) and psychotramide D (1-d).
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[Measurement of umbilical activin A level in preterm infants].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 10-18-2011
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To evaluate the clinical significance of umbilical activin A in preterm infants.
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Crocetin induces cytotoxicity and enhances vincristine-induced cancer cell death via p53-dependent and -independent mechanisms.
Acta Pharmacol. Sin.
PUBLISHED: 10-10-2011
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To investigate the anticancer effect of crocetin, a major ingredient in saffron, and its underlying mechanisms.
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[Preliminary study on the immunological characteristics of permissive and non-permissive hosts infected with Schistosoma japonicum].
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi
PUBLISHED: 10-07-2011
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To study the difference among immune responses of three kinds of experimental animals with different susceptibility to the infection of Schistosoma japonicum, and preliminarily explore the mechanism of the immune response in permissive and non-permissive hosts.
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[Cloning, expression and immunodiagnostic evaluation of antigen EPC1 from Echinococcus granulosus].
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi
PUBLISHED: 10-06-2011
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To clone and express EPCl gene of Echinococcus granulosus, and investigate its immunogenicity and diagnostic value.
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Chemical compositions and anti-influenza activities of essential oils from Mosla dianthera.
J Ethnopharmacol
PUBLISHED: 09-14-2011
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Mosla dianthera as an aromatic herb is used in folk medicine for the treatment of cough, colds, fever, bronchitis, nasal congestion and headache.
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[Value of cardiac CT examination in middle-aged and elderly patients with atrial septal defect before planned transcatheter closure].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 09-09-2011
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To investigate the value of the cardiac CT examination for decision making in middle-aged and elderly patients before planned transcatheter atrial septal defect (ASD) closure.
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What is Visualize?

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

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

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

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.