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Find video protocols related to scientific articles indexed in Pubmed.
Silicon nitride three-mode division multiplexing and wavelength-division multiplexing using asymmetrical directional couplers and microring resonators.
Opt Express
PUBLISHED: 10-17-2014
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We demonstrate silicon nitride mode-division multiplexing (MDM) and wavelength-division multiplexing (WDM) using asymmetrical directional couplers and microring resonators. Our experiments reveal three-mode multiplexing and demultiplexing. We demonstrate 30Gb/s open eye diagrams with an extinction ratio of ~9 dB for each of the three modes. We observe the worst-case modal crosstalk of ~-10 dB. Our analysis of the measured transmission spectra suggests three contributions to the observed crosstalks, with the dominant cause being a compromised input-coupling at the directional couplers in the multiplexer.
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Highly diastereo- and enantioselective copper-catalyzed propargylic alkylation of acyclic ketone enamines for the construction of two vicinal stereocenters.
Chem. Commun. (Camb.)
PUBLISHED: 10-11-2014
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The first highly diastereo- and enantioselective propargylic alkylation of acyclic ketone enamines to form vicinal tertiary stereocenters has been reported by employing copper catalysis in combination with a bulky and structurally rigid tridentate ketimine P,N,N-ligand.
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[Diversity of nitrogen-fixing microorganisms in biological soil crusts of copper mine wastelands].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 09-17-2014
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Biological soil crusts play an important role in increasing the accumulation of organic matter and nitrogen in re-vegetated mining wastelands. The diversity of nitrogen-fixing microorganisms in three types of biological soil crusts (algal crust, moss crust and algal-moss crust) from two wastelands of copper mine tailings were investigated by polymerase chain reaction-denaturing gradient gel electrophoresis, based on the nifH gene of diazotrophs, to investigate: The diversity of nifH gene in the crusts of mine wastelands, and whether and how the nifH gene diversity in the crusts could be affected by the development of plant communities. The algal crust on the barren area displayed the highest nifH gene diversity, followed by the algal-moss crusts within vascular plant communities, and the moss crust displayed the lowest nifH gene diversity. The diversity of diazotrophs in algal-moss crust within vascular plant communities decreased with the increase of height and cover of vascular plant communities. No significant relationship was found between wasteland properties (pH, water content, contents of organic matter, nitrogen and phosphorus and heavy metal concentration) and nifH gene diversity in the crusts. Sequencing and phylogenetic analysis indicated that most nitrogen-fixing taxa in the crusts of mine wastelands belonged to Cyanobacteria, especially nonheterocystous filamentous Cyanobacteria.
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The Alarmin HMGN1 Contributes to Antitumor Immunity and Is a Potent Immunoadjuvant.
Cancer Res.
PUBLISHED: 09-09-2014
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Alarmins are endogenous mediators that are elicited rapidly in response to danger signals, enhancing innate and adaptive immune responses by promoting the recruitment and maturation of antigen-presenting cells (APC). The nucleosome-binding protein HMGN1 is a potent alarmin that binds TLR4 and induces antigen-specific Th1 immune responses, but its contributions to antitumor immunity have not been explored. We found that ovalbumin (OVA)-expressing EG7 mouse thymoma cells grew much faster in Hmgn1-deficient mice than littermate-matched controls. Tumor-bearing Hmgn1(-/-) mice generated fewer OVA-specific CD8 cells in the spleen than EG7-bearing Hmgn1(+/+) mice, suggesting that HMGN1 supported T cell-mediated antitumor immunity. In addition, EG7 tumors expressing HMGN1 grew more slowly than control EG7 tumors, suggesting greater resistance to HMGN1-expressing tumors. This resistance relied on T cell-mediated immunity because it was abolished by in vivo depletion of CD4(+) and CD8(+) T cells. Moreover, mice vaccinated with a DNA vector expressing an HMGN1-gp100 fusion protein manifested gp100-specific, Th1-polarized immune responses, acquiring resistance to challenge with mouse B16F1 melanoma. Overall, our findings show that HMGN1 contributes to antitumor immunity and it may offer an effective adjuvant to heighten responses to cancer vaccines. Cancer Res; 74(21); 5989-98. ©2014 AACR.
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An Objective Measure to Evaluate Actual Body Shape among Children and Adolescents in China.
Biomed. Environ. Sci.
PUBLISHED: 09-06-2014
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The purpose of this study was to explore an objective measure to assess actual body shape of children and adolescents in China.
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Antimicrobial glycoalkaloids from the tubers of Stephania succifera.
Arch. Pharm. Res.
PUBLISHED: 08-23-2014
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Three new glycoalkaloids, N-formyl-asimilobine-2-O-?-D-glucoside (1), (-)-1-O-?-D-glucoside-8-oxotetrahydropalmatine (2), and 1-N-monomethylcarbamate-argentinine-3-O-?-D-glucoside (3) were isolated from tubers of Stephania succifera. The structures were established based on spectroscopic analysis, and the antimicrobial activities of the three glycoalkaloids are reported.
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Hydrogen-Bonded His93 As a Sensitive Probe for Identifying Inhibitors of the Endocannabinoid Transport Protein FABP7.
Chem Biol Drug Des
PUBLISHED: 08-20-2014
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The human brain FABP (FABP7) has been shown to be an intracellular carrier protein that can significantly potentiate the uptake of the endocannabinoid anandamide. For this reason, there is a great interest in the discovery and development of FABP7 inhibitors for treating stress, pain, inflammation, and drug abuse. We found that in the (1) H-NMR spectrum of the protein, a well-separated downfield resonance arising from the hydrogen-bonded His93 side chain is very sensitive to ligand binding. Using this characteristic spectral marker together with another well-resolved upfield resonance from the side chain of Val84, we have identified that an adipocyte FABP (FABP4) inhibitor BMS309403 also binds tightly to FABP7. Our data demonstrated that this unique His93 downfield resonance can be used as a sensitive probe for rapidly and unambiguously identifying novel high-affinity FABP7 ligands. The findings should help accelerate the discovery of potential drug leads for the modulation of endocannabinoid transport.
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Fully human VEGFR2 monoclonal antibody BC001 attenuates tumor angiogenesis and inhibits tumor growth.
Int. J. Oncol.
PUBLISHED: 08-05-2014
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The critical role of VEGFR2 in tumor neovascularization and progression has allowed the design of clinically beneficial therapies based on it. Here we show that BC001, a new fully human anti-VEGFR2 monoclonal antibody, inhibits VEGF-stimulated endothelial cell migration, tube formation, and effectively suppressed the transdifferentiation of cancer stem cells into endothelial cells in vitro. Since BC001 exhibited no activity against the mouse VEGFR2 and mouse based study was required to confirm its efficacy in vivo, BC101, the mouse analogue of BC001, was developed. BC101 significantly attenuated angiogenesis according to Matrigel plug assay and resulted in ~80% growth inhibition of mouse B16F10 homograft tumors relative to vehicle control. Similarly, human analogue BC001 suppressed the growth of human xenograft tumors HCT116 and BGC823. Furthermore, immunohistochemical results showed reduced expression of CD31, VEGFR2 and Ki-67, as well as increased expression of Caspase 3 in BC001-treated tumor, which indicated BC001 was able to significantly decrease microvessel density, suppress proliferation and promote apoptosis. These results demonstrate the fully human VEGFR2 monoclonal antibody BC001 can work as an effective inhibitor of tumor angiogenesis and tumor growth both in vitro and in vivo.
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[Population distribution and antimicrobial activities of endophytes in Toddalia asiatica].
Wei Sheng Wu Xue Bao
PUBLISHED: 07-03-2014
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To study the population composition and antimicrobial activities of endophytes in medicinal plant Toddalia asiatica.
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[Genetic analysis of accumulation and remobilization of water soluble carbohydrates regulated by drought in wheat RIL stem at grain-filling stage].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 07-03-2014
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Recombinant inbred lines (RIL, Longjian 19 x Q9086, F8) and their parents were undertaken to study characteristics of quantitative genetics of water soluble carbohydrates (WSC) accumulation, remobilization and its contribution to grain mass in different main stem internodes at the grain-filling stage as well as the correlations among the target traits under the rainfed (DS) or well-watered (WW) condition. All of the target traits of RIL had wide variations under both water conditions. The variation coefficient ranged from 2.7% to 62.1% under the DS, and from 1.9% to 52.1% under the WW. The diversity index varied from 0.61 to 0.90 under the DS, and from 0.64 to 0.89 under the WW. All tested traits were significantly affected by the genotype, water condition, internode and growth stage. The growth stage exerted strong impacts on the WSC content. The water condition and internode greatly influenced the WSC remobilization rate. But, the WSC contribution rate to grain was jointly controlled by the genotype, water condition and internode. There were significantly positive correlations between the WSC contents at the early flowering and grain-filling stages, the WSC remobilization rate and its contribution rate to grain at pre-anthesis stage, with the higher correlation coefficients under the DS than under the WW. All traits showed low heri- tability under both water conditions (hB2 = 0.31-0.56 under the DS, 0.44-0.67 under the WW). The numbers of gene pairs controlling all traits ranged from 6 to 29 under the DS, and from 3 to 19 under the WW. It indicated that alleles responsible for all the target traits of RIL showed substantially transgressive segregation and greatlysignificant sensitivity to the water condition, confirming the characteristics of quantitative traits.
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Pseudaboydins A and B: novel isobenzofuranone derivatives from marine fungus Pseudallescheria boydii associated with starfish Acanthaster planci.
Mar Drugs
PUBLISHED: 06-04-2014
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Two novel isobenzofuranone derivatives, pseudaboydins A (1) and B (2), along with five known compounds, including (R)-2-(2-hydroxypropan-2-yl)-2,3-dihydro-5-hydroxybenzofuran (3), (R)-2-(2-hydroxypropan-2-yl)-2,3-dihydro-5-methoxybenzofuran (4), 3,3'-dihydroxy-5,5'-dimethyldiphenyl ether (5), 3-(3-methoxy-5-methylphenoxy)-5-methylphenol (6) and (-)-regiolone (7), were isolated from the culture broth of the marine fungus, Pseudallescheria boydii, associated with the starfish, Acanthaster planci. Their structures were elucidated primarily based on NMR and MS data. The absolute configurations of 1-4 were determined by CD spectroscopy and single-crystal X-ray diffraction studies. The cytotoxic and antibacterial activities of 1-4 were evaluated. Pseudaboydin A (1) showed moderate cytotoxic activity against human nasopharyngeal carcinoma cell line HONE1, human nasopharyngeal carcinoma cell line SUNE1 and human glandular lung cancer cell line GLC82 with IC50 values of 37.1, 46.5 and 87.2 ?M, respectively.
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Enantioselective synthesis of highly functionalized dihydrofurans through copper-catalyzed asymmetric formal [3+2] cycloaddition of ?-ketoesters with propargylic esters.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 06-02-2014
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An enantioselective synthesis of highly functionalized dihydrofurans through a copper-catalyzed asymmetric [3+2] cycloaddition of ?-ketoesters with propargylic esters has been developed. With a combination of Cu(OTf)2 and a chiral tridentate P,N,N ligand as the catalyst, a variety of 2,3-dihydrofurans bearing an exocyclic double bond at the 2?position were obtained in good chemical yields and with good to high enantioselectivities. The exocyclic double bond can be hydrogenated in a highly diastereoselective fashion to give unusual cis-2,3-dihydrofuran derivatives, thus further enhancing the scope of this transformation.
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Exposure to Bacillus anthracis capsule results in suppression of human monocyte-derived dendritic cells.
Infect. Immun.
PUBLISHED: 06-02-2014
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The antiphagocytic capsule of Bacillus anthracis is a major virulence factor. We hypothesized that it may also mediate virulence through inhibition of the host's immune responses. During an infection, the capsule exists attached to the bacterial surface but also free in the host tissues. We sought to examine the impact of free capsule by assessing its effects on human monocytes and immature dendritic cells (iDCs). Human monocytes were differentiated into iDCs by interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) over 7 days in the presence of capsule derived from wild-type encapsulated B. anthracis Ames (WT) or a control preparation from an isogenic B. anthracis Ames strain that produces only 2% of the capsule of the WT (capA mutant). WT capsule consistently induced release of IL-8 and IL-6 while the capA mutant control preparation elicited either no response or only a minimal release of IL-8. iDCs that were differentiated in the presence of WT capsule had increased side scatter (SSC), a measure of cellular complexity, when assessed by flow cytometry. iDCs differentiated in the presence of WT capsule also matured less well in response to subsequent B. anthracis peptidoglycan (Ba PGN) exposure, with reduced upregulation of the chemokine receptor CCR7, reduced CCR7-dependent chemotaxis, and reduced release of certain cytokines. Exposure of naive differentiated control iDCs to WT capsule did not alter cell surface marker expression but did elicit IL-8. These results indicate that free capsule may contribute to the pathogenesis of anthrax by suppressing the responses of immune cells and interfering with the maturation of iDCs.
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Combined application of NMR- and GC-MS-based metabonomics yields a superior urinary biomarker panel for bipolar disorder.
Sci Rep
PUBLISHED: 05-08-2014
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Bipolar disorder (BD) is a debilitating mental disorder that cannot be diagnosed by objective laboratory-based modalities. Our previous studies have independently used nuclear magnetic resonance (NMR)-based and gas chromatography-mass spectrometry (GC-MS)-based metabonomic methods to characterize the urinary metabolic profiles of BD subjects and healthy controls (HC). However, the combined application of NMR spectroscopy and GC-MS may identify a more comprehensive metabolite panel than any single metabonomic platform alone. Therefore, here we applied a dual platform (NMR spectroscopy and GC-MS) that generated a panel of five metabolite biomarkers for BD-four GC-MS-derived metabolites and one NMR-derived metabolite. This composite biomarker panel could effectively discriminate BD subjects from HC, achieving an area under receiver operating characteristic curve (AUC) values of 0.974 in a training set and 0.964 in a test set. Moreover, the diagnostic performance of this panel was significantly superior to the previous single platform-derived metabolite panels. Thus, the urinary biomarker panel identified here shows promise as an effective diagnostic tool for BD. These findings also demonstrate the complementary nature of NMR spectroscopy and GC-MS for metabonomic analysis, suggesting that the combination of NMR spectroscopy and GC-MS can identify a more comprehensive metabolite panel than applying each platform in isolation.
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A new triterpenoid saponin and an oligosaccharide isolated from the fruits of Sapindus mukorossi.
Nat. Prod. Res.
PUBLISHED: 05-07-2014
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A new triterpenoid saponin (1) and a new oligosaccharide (2), together with three known saponins (3-5), have been isolated from n-BuOH extract of the fruits of Sapindus mukorossi Gaertn. The structures were elucidated using detailed analysis of one- and two-dimensional nuclear magnetic resonance spectra along with their mass spectrometric data and the results of acid hydrolysis. Of the isolated compounds 1 and 3-5 displayed cytotoxic effects against human cancer cell lines in A-549 (lung carcinoma), MDA-231 (breast carcinoma) and PC-3 (prostatic carcinoma).
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Constituents of the roots of Clausena lansium and their potential anti-inflammatory activity.
J. Nat. Prod.
PUBLISHED: 05-05-2014
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Eight new carbazole alkaloids, claulamines C (1), D (2), and E (5) and clausenalines B-F (3, 4, 6-8), four new coumarins, clausemarins A-D (9-12), and 43 known compounds were isolated from the roots of Clausena lansium. The structures of the new compounds were established on the basis of 2D-NMR spectroscopic analysis, and their absolute configurations were established from their ECD spectra. The configuration of wampetin was revised as E using a NOESY experiment. Most of the isolated compounds were evaluated for their potential anti-inflammatory activity. The results showed that compounds 9, 13-18, and 20-22 exhibited strong inhibition of superoxide anion generation with IC50 values ranging from 1.9 to 8.4 ?M, while compounds 18, 19, and 21 inhibited elastase release with IC50 values in the range from 2.0 to 6.9 ?M.
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Optical and application study of gas-liquid discharge excited by bipolar nanosecond pulse in atmospheric air.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 04-12-2014
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In this study, a bipolar nanosecond pulse with 20ns rising time is employed to generate air gas-liquid diffuse discharge plasma with room gas temperature in quartz tube at atmospheric pressure. The image of the discharge and optical emission spectra of active species in the plasma are recorded. The plasma gas temperature is determined to be approximately 390K by compared the experimental spectra with the simulated spectra, which is slightly higher than the room temperature. The result indicated that the gas temperature rises gradually with pulse peak voltage increasing, while decreases slightly with the electrode gap distance increasing. As an important application, bipolar nanosecond pulse discharge is used to sterilize the common microorganisms (Actinomycetes, Candida albicans and Escherichia coli) existing in drinking water, which performs high sterilization efficiency.
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[Inhibition of the activity of sulfate-reducing bacteria in produced water from oil reservoir by nitrate].
Huan Jing Ke Xue
PUBLISHED: 04-12-2014
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Growth and metabolic activity of sulfate-reducing bacteria (SRB) can result in souring of oil reservoirs, leading to various problems in aspects of environmental pollution and corrosion. Nitrate addition and management of nitrate-reducing bacteria (NRB) offer potential solutions to controlling souring in oil reservoirs. In this paper, a facultive chemolithotrophic NRB, designated as DNB-8, was isolated from the produced fluid of a water-flooded oil reservoir at Daqing oilfield. Then the efficacies and mechanisms of various concentrations of nitrate in combination with DNB-8 in the inhibition of the activity of SRB enriched culture were compared. Results showed that 1.0 mmol x L(-1) of nitrate or 0.45 mmol x L(-1) of nitrite inhibited the sulfate-reducing activity of SRB enrichments; the competitive reduction of nitrate by DNB-8 and the nitrite produced were responsible for the suppression. Besides, the SRB enrichment cultures showed a metabolic pathway of dissimilatory nitrate reduction to ammonium (DNRA) via nitrite. The SRB cultures could possibly alleviate the nitrite inhibition by DNRA when they were subjected to high-strength nitrate.
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Association of Ureaplasma urealyticum colonization with development of bronchopulmonary dysplasia: a systemic review and meta-analysis.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 04-08-2014
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There is controversy regarding the roles of Ureaplasma urealyticum (U. urealyticum) colonization in the development of bronchopulmonary dysplasia (BPD). This study explored the association between U. urealyticum and bronchopulmonary dysplasia at 36 weeks post-menstrual age (BPD36). Studies published before December 31, 2013 were searched from Medline, Embase, Ovid, Web of Science, and Cochrane databases, with the terms "Ureaplasma urealyticum", "chronic lung disease", or "BPD36" used, and English language as a limit. The association between U. urealyticum colonization and BPD36 was analyzed with RevMan 4.2.10 software, using the odds ratio (OR) and relative risk (RR) for dichotomous variables. Out of the enrolled 81 studies, 11 investigated the BPD36 in total 1193 infants. Pooled studies showed no association between U. urealyticum colonization and subsequent development of BPD36, with the OR and RR being 1.03 (95% CI=0.78-1.37; P=0.84) and 1.01 (95% CI= 0.88-1.16, P=0.84), respectively. These findings indicated no association between U. urealyticum colonization and the development of BPD36.
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A new 2-(2-phenylethyl)chromone derivative in Chinese agarwood 'Qi-Nan' from Aquilaria sinensis.
J Asian Nat Prod Res
PUBLISHED: 03-20-2014
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Phytochemical analysis of the high quality Chinese agarwood 'Qi-Nan' originating from Aquilaria sinensis (Lour.) Glig led to the isolation of a new 2-(2-phenylethyl)chromone derivative, qinanones G (1), and four known 2-(2-phenylethyl)chromones (2-5). Their structures were elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR) and MS analyses. The NMR data of chromones 1-3 were first reported, and chromones 2 and 3 showed weak inhibitory activity against acetylcholinesterase.
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Norditerpenoids from Flickingeria fimbriata and their inhibitory activities on nitric oxide and tumor necrosis factor-? production in mouse macrophages.
Molecules
PUBLISHED: 03-10-2014
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Bioassay-guided fractionation of the ethanolic extract of the leaves of Flickingeria flimbriata led to the isolation of two new degraded diterpenoids 1 and 2, a new ent-pimarane type diterpenoid 3, and four known steroids 4-7. The structures of 1-3 were elucidated by spectroscopic analysis, and their absolute configurations were determined by chemical methods, TDDFT quantum chemical calculations of ECD spectra, and CD exiton chirality method. Compounds 1 and 2, named flickinflimilins A and B, possess a rare 15,16-dinor-ent-pimarane skeleton. Compounds 1-7 were screened for the inhibitory activity against lipopolysaccharide (LPS)-induced NO and TNF-? production in RAW264.7 cells. Compounds 1-3 exhibited potent inhibitory activities, with IC50 values of less than 10 µM.
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The discovery of N-((2H-tetrazol-5-yl)methyl)-4-((R)-1-((5r,8R)-8-(tert-butyl)-3-(3,5-dichlorophenyl)-2-oxo-1,4-diazaspiro[4.5]dec-3-en-1-yl)-4,4-dimethylpentyl)benzamide (SCH 900822): a potent and selective glucagon receptor antagonist.
J. Med. Chem.
PUBLISHED: 02-26-2014
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A novel series of spiroimidazolone-based antagonists of the human glucagon receptor (hGCGR) has been developed. Our efforts have led to compound 1, N-((2H-tetrazol-5-yl)methyl)-4-((R)-1-((5r,8R)-8-(tert-butyl)-3-(3,5-dichlorophenyl)-2-oxo-1,4-diazaspiro[4.5]dec-3-en-1-yl)-4,4-dimethylpentyl)benzamide (SCH 900822), a potent hGCGR antagonist with exceptional selectivity over the human glucagon-like peptide-1 receptor. Oral administration of 1 lowered 24 h nonfasting glucose levels in imprinting control region mice on a high fat diet with diet-induced obesity following single oral doses of 3 and 10 mg/kg. Furthermore, compound 1, when dosed orally, was found to decrease fasting blood glucose at 30 mg/kg in a streptozotocin-treated, diet-induced obesity mouse pharmacodynamic assay and blunt exogenous glucagon-stimulated glucose excursion in prediabetic mice.
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Direct-modulated waveguide-coupled microspiral disk lasers with spatially selective injection for on-chip optical interconnects.
Opt Express
PUBLISHED: 02-12-2014
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We investigate direct-modulated waveguide-coupled microspiral disk lasers for on-chip optical interconnects. Microspiral resonators, with a rotationally asymmetric shape and a waveguide directly gapless coupled to the notch, offer a compact unidirectional-emission on-chip laser source. We employ spatially selective injection by means of a ring-shaped p-contact on top of the microdisk rim region to selectively inject current to the whispering-gallery-like modes and thus enhance the laser performance. Here we report room-temperature continuous-wave electrically injected AlGaInAs/InP waveguide-coupled microspiral disk lasers with a disk radius of 30 and 40 ?m. For a 30 ?m microspiral disk laser gaplessly coupled with a 100 ?m-long passive waveguide that is directly connected to an on-chip AlGaInAs/InP photodiode, we estimate a laser output power of at least 200 ?W upon a 70 mA injection. We realize small-signal modulation with a 3dB bandwidth exceeding 10 GHz for the 30 ?m microspiral disk. We demonstrate an open eye diagram at 15 Gbit/s with a bias current of 90 mA at a stage temperature of 15 °C.
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Thin-layer chromatographic identification of Chinese propolis using chemometric fingerprinting.
Phytochem Anal
PUBLISHED: 02-04-2014
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Poplar tree gum has a similar chemical composition and appearance to Chinese propolis (bee glue) and has been widely used as a counterfeit propolis because Chinese propolis is typically the poplar-type propolis, the chemical composition of which is determined mainly by the resin of poplar trees. The discrimination of Chinese propolis from poplar tree gum is a challenging task.
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Anti-hepatitis C virus dinorditerpenes from the roots of Flueggea virosa.
J. Nat. Prod.
PUBLISHED: 01-08-2014
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Along with four known terpenoids (1-4), eight new dinorditerpenes (5-12) were isolated and identified from the roots of Flueggea virosa. The absolute configurations of 4-6 were determined by the Mosher's method, and that of 5 was confirmed by single-crystal X-ray diffraction analysis. Using the hepatitis C virus cell culture infection system, compounds 1, 3, 11, and 12 exhibited significant anti-HCV activity with EC50 values of 5.6, 5.0, 7.5, and 6.6 ?M, respectively. Compounds 11 and 12 were nontoxic toward the tested Huh7.5 cell lines.
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Trinorditerpenes from the roots of Flueggea virosa.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-07-2014
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Two trinorditerpenes, flueggrenes A and B (1 and 2), have been isolated from the roots of Flueggea virosa. Their structures were established by extensive analyses of spectroscopic data. The isolates were evaluated for anti-HCV activity, as well as the inhibition of superoxide anion generation and elastase release in response to FMLP/cytochalasin B.
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Preparation, characterization, and pharmacodynamics of thermosensitive liposomes containing docetaxel.
J Pharm Sci
PUBLISHED: 01-04-2014
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A novel thermosensitive liposome (TL) containing docetaxel (DTX) was designed to enhance DTX-targeted delivery and antitumor effect. TL loading DTX (DTX-TL) were prepared by thin film hydration. The mean particle size of the liposomes was about 100 nm, and the drug entrapment efficiency was more than 95%. The phase transition temperature of liposomes was about 42 °C. In vitro drug release showed that drug released at 37 °C was obviously less than that at 42 °C. For in vivo experiments, the human breast tumor model was established by subcutaneous xenotransplantation on nude mice; liposomes and injection containing DTX were injected i.v. in nude mice, followed by exposure of the tumors to hyperthermia (HT) for 30 min after administration. The tumor inhibition ratio of DTX-TL group was significantly higher than the normal injection group. Combining TL with HT enhanced the delivery of DTX and thereby its antitumor effects. The liposomes reported in this paper could potentially produce viable clinical strategies for improved targeting and delivery of DTX for the treatment of breast cancer.
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IV. Discovery of CXCR3 antagonists substituted with heterocycles as amide surrogates: improved PK, hERG and metabolic profiles.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-03-2014
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The structure-human CXCR3 binding affinity relationship of a series of pyridyl/pyrazinyl-piperazinyl-piperidine derivatives were explored with a focus to improve PK, hERG and metabolic profiles. Several small heterocycles were identified as amide surrogates, which minimized many potential metabolite issues. During the course of SAR development, we have observed the additive effect of desirable functional groups to improve hERG and PK profiles which lead to the discovery of many clinically developable CXCR3 antagonists with excellent overall profile.
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Nanoparticle drug- and gene-eluting stents for the prevention and treatment of coronary restenosis.
Theranostics
PUBLISHED: 01-01-2014
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Percutaneous coronary intervention (PCI) has become the most common revascularization procedure for coronary artery disease. The use of stents has reduced the rate of restenosis by preventing elastic recoil and negative remodeling. However, in-stent restenosis remains one of the major drawbacks of this procedure. Drug-eluting stents (DESs) have proven to be effective in reducing the risk of late restenosis, but the use of currently marketed DESs presents safety concerns, including the non-specificity of therapeutics, incomplete endothelialization leading to late thrombosis, the need for long-term anti-platelet agents, and local hypersensitivity to polymer delivery matrices. In addition, the current DESs lack the capacity for adjustment of the drug dose and release kinetics appropriate to the disease status of the treated vessel. The development of efficacious therapeutic strategies to prevent and inhibit restenosis after PCI is critical for the treatment of coronary artery disease. The administration of drugs using biodegradable polymer nanoparticles as carriers has generated immense interest due to their excellent biocompatibility and ability to facilitate prolonged drug release. Despite the potential benefits of nanoparticles as smart drug delivery and diagnostic systems, much research is still required to evaluate potential toxicity issues related to the chemical properties of nanoparticle materials, as well as to their size and shape. This review describes the molecular mechanism of coronary restenosis, the use of DESs, and progress in nanoparticle drug- or gene-eluting stents for the prevention and treatment of coronary restenosis.
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[Chemical constituents from stems of Aquilaria sinensis].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 12-31-2013
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To study the constituents from the stems of Aquilaria sinensis.
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[Chemical constituents of Aconitum bulleyanum].
Zhong Yao Cai
PUBLISHED: 12-31-2013
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To study the chemical constituents of chloroform fraction from Aconitum bulleyanum.
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[Analysis on follow-up efficacy and safety of slow transit constipation treated with individualized deep puncture at Tianshu (ST 25): a multi-central randomized controlled trial].
Zhongguo Zhen Jiu
PUBLISHED: 12-31-2013
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To evaluate the follow-up efficacy and safety on slow transit constipation (STC) treated with individualized deep puncture at Tianshu (ST 25).
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[Effect of toluene diisocyanate on lung function of workers].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 12-28-2013
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To investigate the effect of long-term exposure to toluene diisocyanate (TDI) on the lung function of TDI-exposed workers.
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[Causes of insufficient anticoagulation in Chinese patients with non-valvlar atrial fibrillation].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 12-28-2013
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To evaluate the factors responsible for the insufficient application of oral anticoagulation (OAC) in Chinese patients with non-valvular atrial fibrillation.
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[Removal of estrogens in laccase catalyzed oxidative processes].
Huan Jing Ke Xue
PUBLISHED: 11-07-2013
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The removal of 5 estrogens (bisphenol A, estradiol, ethinylestradiol, estrone and octylphenol) in laccase catalyzed oxidative processes was studied. The effects of pH and NOM on the removal of EDCs were discussed in detail, as well as the kinetics of EE2 removal and the reaction products. The results indicated that laccase was capable of removing estrogens efficiently. The optimal pH was between 4 and 6. NOM significantly inhibited the removal of estrogens at the initial stage of the reaction. However, the adverse effect of NOM was not obvious after 24 h treatment. The removal of EE2 obeyed the second-order kinetics. The activity of laccase remained stable during the reactions and the stability was higher than that of peroxidase. MS analysis demonstrated that the EE2 dimer formed through radical coupling mechanism was the main reaction product.
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[Effects of source-sink regulation on water soluble carbohydrates of vegetative organs and thousand-grain mass of wheat under different water conditions].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 11-02-2013
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Two winter wheat cultivars with different drought tolerance were selected to investigate the effects of source-sink regulation on the vegetative organs water soluble carbohydrates (WSC) content and 1000-grain mass (TGM) of wheat under drought stress (DS) and well watered (WW) conditions. Sink-cutting increased the WSC content of different vegetative organs significantly, and promoted the relative transportation of the WSC positively; while source-cutting caused opposite responses. The effects of source-sink regulation on the WSC content and its relative transportation amount (TA) and transportation rate (TR) were significantly higher under DS and sink-cutting than under WW and source-cutting, for drought-resistant cultivar (Longjian 19) than for drought-sensitive Q9086, and for peduncle internode and PedI than for penultimate internode and PenI. Under source-cutting, the superior organs of Longjian 19 in the TR of total WSC were sheath, PedI, and PenI, which also contributed to the fructan TR of the two cultivars, while those of Q9086 were the PenI and the third internode from top (ThiI). Source-cutting decreased the TGM of Longjian 19 and Q9086 significantly, with the decrement being 27.3% and 31.7% under DS and 25.3% and 12.1% under WW, respectively. The correlation coefficients of the WSC content and its TA and TR and the TGM were significantly higher under sink-cutting than under source-cutting, and also, under DS than under WW. There existed a higher correlation coefficient (r2 > 0.900) of the TGM and the total WSC and fructan contents in different vegetative organs. The vegetative organs with closer correlation between their WSC content and its TA and TR and the TGM were mainly sheath and PedI. Under DS, the traits associated with the total WSC content had a higher correlation with TGM; under WW, the traits associated with sucrose and glucan contents generally showed a higher correlation with TGM. It was suggested that the effects of source-sink regulation on the WSC content of vegetative organs and the TGM were significantly affected by soil water environment, wheat genotype, and vegetative organs location.
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Enantioselective Copper-Catalyzed Decarboxylative Propargylic Alkylation of Propargyl ?-Ketoesters with a Chiral Ketimine P,N,N-Ligand.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 10-21-2013
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The first enantioselective copper-catalyzed decarboxylative propargylic alkylation has been developed. Treatment of propargyl ?-ketoesters with a catalyst, prepared in situ from [Cu(CH3 CN)4 BF4 ] and a newly developed chiral tridentate ketimine P,N,N-ligand under mild reaction conditions, generates ?-ethynyl ketones in good yields and with high enantioselectivities without requiring the pregeneration of ketone enolates. This new process provides facile access to a range of chiral ?-ethynyl ketones in a highly enantioenriched form.
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A large-area diffuse air discharge plasma excited by nanosecond pulse under a double hexagon needle-array electrode.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 10-06-2013
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A large-area diffuse air discharge plasma excited by bipolar nanosecond pulse is generated under a double hexagon needle-array electrode at atmospheric pressure. The images of the diffuse discharge, electric characteristics, and the optical emission spectra emitted from the diffuse air discharge plasma are obtained. Based on the waveforms of pulse voltage and current, the power consumption, and the power density of the diffuse air discharge plasma are investigated under different pulse peak voltages. The electron density and the electron temperature of the diffuse plasma are estimated to be approximately 1.42×10(11)cm(-3) and 4.4eV, respectively. The optical emission spectra are arranged to determine the rotational and vibrational temperatures by comparing experimental with simulated spectra. Meanwhile, the rotational and vibrational temperatures of the diffuse discharge plasma are also discussed under different pulse peak voltages and pulse repetition rates, respectively. In addition, the diffuse air discharge plasma can form an area of about 70×50mm(2) on the surface of dielectric layer and can be scaled up to the required size.
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[Effect of subchronic inhalation of ethylbenzene on expression of heme oxygenase-1 in rat renal tissues].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 09-24-2013
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To investigate the effect of ethylbenzene on the expression of heme oxygenase-1 (HO-1) inratrenal tissues.
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[The inhibitory effect of latent transforming growth factor ?1 activation and silicosis by CD36 targeted RNA interference in silicosis model of rat].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 09-24-2013
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To investigate the inhibitory effects of CD36-targeting RNA interference on the latent transforming growth factor ?1 (L-TGF-?1) activation and silicotic fibrosis in rat silicosis model.
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[Expression of cation-chloride cotransporters KCC2 and NKCC1 in brainstem of para- chlorophenylalanine-induced acute insomnia rats].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 09-14-2013
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To explore the possible roles of KCC2 and NKCC1 in the pathological mechanism of acute insomnia in rats.
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[Chlorination of ethynyl estradiol: a kinetic and mechanistic study].
Huan Jing Ke Xue
PUBLISHED: 08-17-2013
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The objective of this research is to explore the fundamentals of reactions between chlorine and ethynyl estradiol (EE2), which is expected to occur during the drinking water treatment. The first step of EE2 chlorination was shown to follow the second-order kinetics with the first order to concentrations of both target compound and chlorine, respectively. Apparent rate constants of EE2 chlorination exhibit the pH-dependent profile which indicates that the phenolic ring is the preferred site of attack by Cl. The transformation of EE2 is governed by 3 elementary reactions between different species of EE2 and HClO. The deprotonated EE2 anion is significantly more reactive than its neutral conjugate. HPLC/MS analysis revealed that several Cl atoms can be incorporated into this site via complex multi-step pathways, resulting in the formation of mono and di-chlorine substituted EE2. The incorporation of the third Cl is accompanied by immediate broken down of the ring via hydrolysis. The results of this study are helpful to fully understand the behavior of EE2 in chlorinated drinking water disinfection, provide the basis for evaluating the potential exposure of this contaminant to human. The data of this work also give insights to the formation of chlorinated drinking water disinfection by-products (DBPs).
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Characterization and determination of 2-(2-phenylethyl)chromones in agarwood by GC-MS.
Molecules
PUBLISHED: 07-31-2013
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Agarwood is the fragrant resinous heartwood obtained from certain trees in the genus Aquilaria belonging to the family Thymelaeaceae. 2-(2-Phenylethyl)chromones and characteristic sesquiterpenes are the main classes of aromatic compounds isolated from agarwood. Although there are many sesquiterpenes, relatively few 2-(2-phenylethyl)chromones have been determined in agarwood by GC-MS. After analysis of the MS spectra of eighteen 2-(2-phenylethyl)chromone derivatives isolated from agarwood and identified by NMR spectroscopy, together with the reported MS data and characteristic of structures of 2-(2-phenylethyl)chromones, the MS characterization, fragmentation patterns and characteristic fragment peaks for the compounds were deduced and a table summarizing MS characterization of 2-(2-phenylethyl)chromones in agarwood is presented. All the 2-(2-phenylethyl)chromones previously reported in agarwood are substituted by methoxy or/and hydroxy groups, except for one compound. Due to the fact they all possess the same basic skeleton (molecular weight: 250) and similar substituent groups (methoxy or hydroxy groups), a formula (30m + 16n = MW - 250) is provided to calculate the number of methoxy (m) or hydroxy (n) groups according to molecular ion peak or molecular weight (MW). We deduced that the characteristic fragmentation behaviors of the 2-(2-phenylethyl)chromones are the cleavages of the CH?-CH? bond between chromone moiety and phenyl moiety. Thus, characteristic fragment ions, such as m/z 91 [C?H?], 107 [C?H?+OH], 121 [C?H?+OCH?], 137 [C?H5+OH+OCH?] are formed by different substituted benzyl moieties, while characteristic fragment ions such as m/z 160 [C??H?O?], 176 [C??H?O?+OH], 190 [C??H?O?+OCH?], 220 [C??H?O?+OCH?×2] are formed by different substituted chromone moieties. Furthermore, rules regarding to the relationship between the positions of hydroxy or methoxy groups and the relative abundances of benzyl and chromone fragment ions have been deduced. Elucidation of how the positions of hydroxy or methoxy groups affect the relative abundances of benzyl and chromone fragment peaks is also provided. Fifteen unidentified compounds of an artificial agarwood sample analyzed by GC-MS, were preliminary determined as 2-(2-phenylethyl)chromones by analysis of their MS characterization and by comparison of their MS spectra with those of 18 standard compounds or 2-(2-phenylethyl)chromones reported in literature according to the above-mentioned methods and rules. This report will be helpful for the analysis and structural elucidation of 2-(2-phenylethyl)chromones in agarwood by GC-MS, and provides fast and reliable characterization of the quality of agarwood.
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Analysis of vertical radiation loss and far-field pattern for microcylinder lasers with an output waveguide.
Opt Express
PUBLISHED: 07-12-2013
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Vertical radiation loss and far-field pattern are investigated for microcylinder lasers by 3D FDTD simulation and experimentally. The numerical results show that an output waveguide connected to the microcylinder resonator can result in additional vertical radiation loss for high Q coupled modes and affect the far field pattern. The vertical radiation loss can be controlled by adjusting the up cladding layer thickness. Furthermore, two lobes of vertical far-field patterns are observed for a 15-?m-radius microcylinder laser connected with an output waveguide, which confirms the vertical radiation loss.
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Immune microenvironment profiles of tumor immune equilibrium and immune escape states of mouse sarcoma.
Cancer Lett.
PUBLISHED: 07-05-2013
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Cancer immunoediting consists of three distinct phases: elimination, equilibrium and escape. Here, for the first time, we investigated the immune microenvironment profiles of tumor immune equilibrium and immune escape states in 3-methylcholanthrene-induced murine sarcoma model. Our study indicates the relative balance of monocytic MDSCs and antitumor immunity cells (especially CTLs, NK cells and ??T cells) may involve in maintaining tumor cells in a state of immune-mediated dormancy. In addition, high percentages of Treg cells and PMN-MDSCs are associated with the tumor immune escape state - mice with progressing sarcomas. In summary, the relative balance of immune effector cells and suppressive populations in the tumor microenvironment may involve in determining the fate of tumors.
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An uniform DBD plasma excited by bipolar nanosecond pulse using wire-cylinder electrode configuration in atmospheric air.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 07-01-2013
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In this study, a bipolar nanosecond pulsed power supply with 15ns rising time is employed to generate an uniform dielectric barrier discharge using the wire-cylinder electrode configuration in atmospheric air. The images, waveforms of pulse voltage and discharge current, and the optical emission spectra of the discharges are recorded. The rotational and vibrational temperatures of plasma are determined by comparing the simulated spectra with the experimental spectra. The effects of pulse peak voltage, pulse repetition rate and quartz tube diameter on the emission intensities of N2 (C(3)?u?B(3)?g, 0-0) and N2(+)B(2)?u(+)?X(2)?g(+),0-0 and the rotational and vibrational temperatures have been investigated. It is found that the uniform plasma with low gas temperature can be obtained, and the emission intensities of N2 (C(3)?u?B(3)?g, 0-0) and N2(+)B(2)?u(+)?X(2)?g(+),0-0 rise with increasing the pulse peak voltage and pulse repetition rate, while decrease as the increase of quartz tube diameter. In addition, under the condition of 28kV pulse peak voltage, 150Hz pulse repetition rate and 7mm quartz tube diameter, the plasma gas temperature is determined to be 330K. The results also indicate that the plasma gas temperature keep almost constant when increasing the pulse peak voltage and pulse repetition rate but increase with the increase of the quartz tube diameter.
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?-Defensin 2 and 3 promote the uptake of self or CpG DNA, enhance IFN-? production by human plasmacytoid dendritic cells, and promote inflammation.
J. Immunol.
PUBLISHED: 06-17-2013
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Alarmins are a group of structurally diverse host defense antimicrobial peptides that are important immune activators. In this article, we present a novel role for two potent alarmins, human ?-defensin 2 and 3 (HBD2 and 3), in promoting IFN-? production by human plasmacytoid dendritic cells. We demonstrate that HBD2 and 3 activate pDCs by enhancing the intracellular uptake of CpG and self DNA and promote DNA-induced IFN-? production in a TLR9-dependent manner. Both CpG and host DNA form aggregates that resemble DNA nets when combined with HBD2 and 3. Isothermal titration calorimetry studies to elucidate the nature of HBD3/CpG complexes demonstrate involvement of enthalpy-driven interactions, in addition to hydrophobic interactions, with the formation of complexes at a molar ratio of 2:1 defensin/CpG. The i.v. administration of HBD3/CpG complexes induced proinflammatory cytokines like IL-12, IFN-?, IL-6, IFN-?, and IL-10 in serum, associated with an increased recruitment of APCs in the spleen. Subcutaneous injections of these complexes showed enhanced infiltration of inflammatory cells at the injection site, indicating a potential pathophysiological role for alarmin/DNA complexes in contributing to inflammation. Intraperitoneal immunization of HBD3/CpG complexes with OVA enhanced both cellular and humoral responses to OVA, compared with OVA/HBD3 or OVA/CPG alone, indicative of a much more potent adjuvant effect of the HBD3/CpG complexes. Thus, the ability of defensins to enhance cellular uptake of nucleic acids can lead to improved vaccine formulations by promoting their uptake by various cells, resulting in an enhanced immune response.
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[Preparation of OMC-Au/L-Lysine/Au modified glassy carbon electrode and the study on its detection response to hydroquinone and catechol].
Huan Jing Ke Xue
PUBLISHED: 06-11-2013
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Ordered mesoporous carbon-Au nanoparticles (OMC-Au) nanocomposites were synthesized by a one-step chemical reduction route, and an OMC-Au/L-Lysine/Au composite film-modified glassy carbon electrode (GCE) was constructed. The microstructure of OMC and OMC-Au/L-Lysine/Au composite films were characterized by SEM, and the preparation process of OMC-Au/L-Lysine/Au modified glassy carbon electrode was investigated using cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic oxidation of hydroquinone and catechol on the modified electrode was discussed by differential pulse voltammetry in this study, and a sensor for separate determination of hydroquinone and catechol based on OMC-Au/L-Lysine/Au modified glassy carbon electrode was developed. Under the optimal conditions, the cathodic peak current was linearly related to hydroquinone concentration over ranges from 1.0 x 10(-6) mol x L(-1) to 8.0 x 10(-4) mol x L(-1) with a detection limit of 3.0 x 10(-7) mol x L(-1), and linearly related to catechol concentration from 1.0 x 10(-7) mol x L(-1) to 8.0 x 10(-5) mol x L(-1) with a detection limit of 8.0 x 10(-7) mol x L(-1).
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Combination of high-sensitivity C-reactive protein and homocysteine predicts the short-term outcomes of Chinese patients with acute ischemic stroke.
Neurol. Res.
PUBLISHED: 05-28-2013
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Ischemic stroke is one of the most common causes of death worldwide. Early and accurate prediction of outcome in acute ischemic stroke (AIS) is important and influences risk-optimized therapeutic strategies. We investigated the changes in high-sensitivity C-reactive protein (Hs-CRP) and homocysteine (HCY) levels, two of the risk factors, during the acute period of AIS and evaluated the relationship between these levels and short-term prognosis.
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Seroprevalence of antipolio antibodies among children <15 years of age in border provinces in China.
Clin. Vaccine Immunol.
PUBLISHED: 05-15-2013
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Despite remarkable progression toward polio eradication worldwide, wild poliovirus (WPV) importation has been a great challenge for China, as it shares borders with countries where WPV is endemic. The objective of this study was to estimate poliovirus antibody seroprevalence among children <15 years of age in 3 border provinces (Yunnan Province, Tibet Autonomous Region, and Xinjiang Uygur Autonomous Region) in China. A cross-sectional, hospital-based study was undertaken in 3 border provinces in 2010. Individuals <15 years old who visited hospitals at the prefecture level or above to have their blood drawn for any reason were invited to participate in our study. Neutralizing antibody titers to polio serotypes 1 (P1), P2, and P3 were assayed according to the World Health Organization manual for the virological investigation of polio. Antibody titers of ?8 were considered positive. Among the 1,360 subjects enrolled, 1,220 (89.7%), 1,259 (92.6%), and 1,112 (81.8%) were seropositive to P1, P2, and P3, respectively, and 1,051 (77.3%) subjects were seropositive to all three serotypes. The highest seropositive rates were observed in Xinjiang Uygur Autonomous Region. By age, 3- to 5-year-old subjects had the highest rate of seropositivity, and seropositivity decreased significantly with increasing age. The risk of WPV importation will continue until WPV transmission has been interrupted worldwide. Consistent with the Global Polio Eradication Initiatives polio endgame strategy, China must maintain its polio-free status by ensuring adequate population immunity against polio. Because immunity wanes with increasing age, a booster dose with bivalent type 1 and 2 oral poliovirus vaccine could be considered for teenagers in China.
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[Influence of ethylbenzene on oxidative damage and apoptosis in rat renal epithelial cells NRK-52e].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 05-14-2013
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To study the oxidative damage and apoptosis of renal tubular epithelial cells (NRK-52e cell line) induced by ethylbenzene.
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Evaluation acaricidal efficacy of botanical extract from Eupatorium adenophorum against the hard tick Haemaphysalis longicornis (Acari: Ixodidae).
Exp. Parasitol.
PUBLISHED: 05-10-2013
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The aim of this study was to evaluate the acaricidal activity of a botanical extract from Eupatorium adenophorum against the hard tick Haemaphysalis longicornis. This could result in developing effective extracts of E. adenophorum as a source of natural, low-toxicity plant-based acaricidal drugs. Adult engorged females of H. longicornis were collected from naturally infected goats. The engorged females were reared in the laboratory and their offspring (larvae and nymphs) were used as test ectoparasites. The toxic effects of botanical extracts from E. adenophorum against larvae and nymphs of H. longicornis were evaluated. The results showed that the extracts with 1.5 and 1.0g/ml (w/v) concentrations were toxic for H. longicornis, comparable to a toxic effect of 2% chlorpyrifos (positive control). The median lethal time (LT50) for larval and nymphal ticks with 1.5g/ml (w/v) concentration of extract were 0.790 (LT99=1.065) and 1.018 (LT99=10.608) hours, respectively, whereas the LT50 of 1.0g/ml (w/v) concentration were 1.445 (LT99=6.047) and 1.313 (LT99=29.932) hours for larval and nymphal ticks, respectively. At a concentration of 1.5g/ml (w/v), an acaricidal effect of 100% was achieved for both larval and nymphal ticks, while a concentration of 1.0g/ml (w/v) resulted in 100% (for larvae) and 93% (for nymphs) within a 6h period. In additional, we found that the relatively low concentration (0.5g/ml) also obtained a good acaricidal effect during the short experimental period, with 2.22 and 2.651h LT50 for larval and nymphal ticks, respectively. These results indicate that E. adenophorum contains potent acaricidal ingredients against the hard tick H. longicornis.
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[Impact of Pax-8 gene interference on mitochondrial function and cardiomyocyte apoptosis].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 05-09-2013
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To observe the effects of paired box gene 8 (Pax-8) silencing by RNA interference on mitochondrial function and cardiomyocytes apoptosis.
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Preclinical evaluation of herpes simplex virus armed with granulocyte-macrophage colony-stimulating factor in pancreatic carcinoma.
World J. Gastroenterol.
PUBLISHED: 05-01-2013
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To investigate the therapeutic efficacy and mechanisms of action of oncolytic-herpes-simplex-virus encoding granulocyte-macrophage colony-stimulating factor (HSV(GM-CSF)) in pancreatic carcinoma.
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[Optical diagnosis of large area homogenous dielectric barrier discharge in nitrogen at atmospheric pressure].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 04-17-2013
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In the present study, dielectric barrier homogenous discharge in nitrogen was obtained between large plate electrodes (150 x 300 mm) at atmospheric pressure and the emission spectra of N2 (C3pi(u) --> B3 pi(g)) and N2+ (B2 sigma(u)+ --> X2 sigma(g)+ 0-0 391.4 nm) were recorded. It was found that both the emission intensities of N2 (C3 pi(u) --> B3 pi(g) and N2+ (B2 sigma(u)+ --> X2 sigma(g)+ 0-0 391.4 nm) increase with the rising of the applied voltage and the driving frequency, respectively. The main physicochemical formation mechanism of N2+ (B2 sigma(u)+) in N2 and He+N2 mixtures homogenous discharge was discussed, and the penning ionization was proved to be the dominant formation mechanism.
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The influencing factors of nanosecond pulse homogeneous dielectric barrier discharge in air.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 04-11-2013
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In this paper, a bipolar nanosecond high pulse voltage with 20 ns rising time was employed to generate homogeneous dielectric barrier discharges using the plate-plate electrode configuration in air at atmospheric pressure. The effects of pulse peak voltage, gas discharge gap, and dielectric plates made by different materials or thicknesses on the discharge homogeneity, voltage-current waveform, and optical emission spectra were investigated. Results show that aforementioned parameters have a strongly impact on the discharge homogeneity and the optical emission spectra, but it is hard to identify definitely their influences on the discharge voltage-current waveform. Homogeneous discharges were easily observed when using low permittivity dielectric plate and the emission intensity of N2 (C(3)?u?B(3)?g, 0-0, 337.1 nm) increases with the rising of pulse peak voltage and the permittivity of dielectric material but decreases with the increasing of gas discharge gap and the dielectric plate thickness. The rotational and vibrational temperatures (Trot and Tvib) were determined at Trot=350±5 K and Tvib=3045 K via fitting the simulative spectra of N2 (C(3)?u?B(3)?g, 0-2) with the measured one.
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Hirayama Disease in Children From Mainland of China.
J. Child Neurol.
PUBLISHED: 04-02-2013
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Hirayama disease is characterized by asymmetrical focal weakness and atrophy of the distal upper limbs with onset in the teens and early 20s. This retrospective study aims to review clinical features of the children (onset before the age of 18 years) with Hirayama disease from mainland of China. Sixty-five children who fulfilled the clinical criteria for Hirayama disease were enrolled. The mean age of onset was 15.7 years, 3.3 years later than the peak age for the normal growth curve. Electrophysiology studies showed chronic denervation changes in C7-T1 segments with normal sensory nerve conduction. Flexion cervical magnetic resonance imaging (MRI) showed forward shifting of the posterior dural sac and engorgement of the posterior epidural venous plexus. Therapeutic intervention with cervical collar can induce a premature arrest of disease progression. Knowledge and awareness of Hirayama disease will facilitate diagnosis and therapeutic intervention in its early stages.
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Antidiarrheal properties of different extracts of Chinese herbal medicine formula Bao-Xie-Ning.
J Integr Med
PUBLISHED: 03-20-2013
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Bao-Xie-Ning (BXN), a traditional Chinese herbal medicine (CHM) formula composed of Fructus Evodiae, Flos Caryophylli and Cortex Cinnamomi, and used for the treatment of infant diarrheal illness, was subject to systematic assessment for its putative multiple pharmacodynamic effects and pharmacological antidiarrheal mechanisms.
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Alarmin-induced cell migration.
Eur. J. Immunol.
PUBLISHED: 03-13-2013
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Alarmins are endogenous, constitutively available, damage-associated molecular patterns that upon release can mobilize and activate various leukocytes for the induction of innate and adaptive immune responses. For our immune system to function appropriately, it relies on navigating various leukocytes to distinct places at the right time. The direction of cell migration is determined by chemotactic factors that include classical chemoattractants, chemokines, certain growth factors, and alarmins. This viewpoint provides an overview of alarmin-induced cell migration. Alarmins are capable of inducing the migration of diverse types of leukocytes and nonleukocytes either directly by triggering specific receptors or indirectly by inducing production of chemokines through the activation of various leukocytes via pattern recognition receptors. The receptors used by alarmins to directly induce cell migration can either be G?i protein-coupled receptors or receptors such as the receptor for advanced glycation end products; however, the intracellular signaling events responsible for the direct chemotactic activities of alarmins are, to date, only partially elucidated. Given that alarmins act in concert with chemokines to regulate the recruitment and trafficking of leukocytes, these damage-associated molecular patterns are potentially involved in diverse biological processes as discussed in this viewpoint.
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Two new types of bisindole alkaloid from Trigonostemon lutescens.
Org. Lett.
PUBLISHED: 03-12-2013
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Six unprecedented bisindole alkaloids, trigolutesins A and B (1-2) with a unique polycyclic skeleton and trigolutes A-D (3-6) with another polycyclic skeleton, were isolated from the twigs of Trigonostemon lutescens. Their structures and relative configurations were elucidated by spectroscopic data and single-crystal X-ray diffraction crystallography. Trigolutesin A (1) showed weak AChE inhibitory activity.
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Anesthetic management of conjoined twins undergoing one-stage surgical separation: A single center experience.
Pak J Med Sci
PUBLISHED: 02-28-2013
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Objective: To summarize our experience in the anesthetic management of conjoined twins undergoing one-stage surgical separation. Methodology: Medical records of conjoined twins admitted to our hospital for treatment and considered for surgical separation from 1996 to present were retrospectively reviewed. Four cases of conjoined twins underwent one-stage surgical separation under general anesthesia. Preoperative evaluation was performed to determine the extent of anatomical conjunction and associated anomalies. Anesthesia was simultaneously induced in all conjoined twins. The intubation procedure was successfully performed with the head slightly rotated to each babys side, followed by the administration of vecuronium. Anesthetic agents were administered according to the estimated weight of each baby. One case of conjoined twins underwent surgical separation with cardiopulmonary bypass due to shared hearts. Results : All conjoined twins were successfully separated. No significant respiratory or cardiac events occurred during surgery except for one twin, which died after separation because of complicated congenital heart disease. Conclusions : Accurate preoperative evaluation, respiratory and circulatory management, and close cooperation of the multidisciplinary team are important aspects of anesthetic management of conjoined twins surgery.
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Quantitative study of the interactome of PKC? involved in the EGF-induced tumor cell chemotaxis.
J. Proteome Res.
PUBLISHED: 02-21-2013
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Chemotaxis plays an important role in metastasis. In our previous studies, we reported that protein kinase C ? (PKC?) mediated cancer cell chemotaxis by regulating cytoskeleton rearrangement and cell adhesion. To further study the molecular mechanism of chemotaxis, mass spectrometry-based approaches were employed to investigate the interactome of PKC? and its changes upon stimulation by epidermal growth factor (EGF). As a result, 233 proteins were identified as potential PKC? binding partners. Label free quantification was applied to examine the quantitative changes of these interactions involved in the EGF induced chemotaxis. Fifteen identified proteins were enriched and 9 proteins were reduced in the presence of EGF (? 1.5 folds, p ? 0.05). The interaction between cofilin-1 (CFL1) and PKC? was evidenced and this interaction was enhanced in the EGF induced chemotaxis signaling transduction. In addition, novel PKC? interacting proteins potentially related with chemotaxis were characterized, such as isoform 1 of nucleophosmin (NPM1). Furthermore, Western blotting and chemotaxis assays were also applied to validate the proteomics result and explore its biological implications. Collectively, the combination of quantitative proteomics and biological assays provides a powerful strategy for elucidating the signaling pathway of tumor cell chemotaxis.
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A new antibacterial denitroaristolochic acid from the tubers of Stephania succifera.
J Asian Nat Prod Res
PUBLISHED: 02-18-2013
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A new denitroaristolochic acid, demethylaristofolin C (1), together with six known alkaloids, crebanine N-oxide (2), (-)-sukhodianine-?-N-oxide (3), palmatine (4), corydalmine (5), dehydrocorydalmine (6), and corynoxidine (7), was isolated from the tubers of Stephania succifera. The structure of demethylaristofolin C was elucidated by spectroscopic techniques (UV, IR, 1D, and 2D NMR) and HR-ESI-MS analyses. These compounds exhibited antibacterial activities against Staphylococcus aureus and methicillin-resistant S. aureus strains in different degrees.
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Interleukin-27 is a potent inhibitor of cis HIV-1 replication in monocyte-derived dendritic cells via a type I interferon-independent pathway.
PLoS ONE
PUBLISHED: 02-11-2013
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IL-27, a member of the IL-12 family of cytokines, plays an important and diverse role in the function of the immune system. Whilst generally recognized as an anti-inflammatory cytokine, in addition IL-27 has been found to have broad anti-viral effects. Recently, IL-27 has been shown to be a potent inhibitor of HIV-1 infection in CD4+ T cells and macrophages. The main objective of this study was to see whether IL-27 has a similar inhibitory effect on HIV-1 replication in dendritic cells (DCs). Monocytes were differentiated into immature DCs (iDCs) and mature DCs (mDCs) with standard techniques using a combination of GM-CSF, IL-4 and LPS. Following differentiation, iDCs were infected with HIV-1 and co-cultured in the presence or absence of IL-27. IL-27 treated DCs were shown to be highly potent inhibitors of cis HIV-1, particularly of CCR5 tropic strains. Of note, other IL-12 family members (IL-12, IL-23 and IL-35) had no effect on HIV-1 replication. Microarray studies of IL-27 treated DCs showed no up-regulation of Type I (IFN) gene expression. Neutralization of the Type-I IFN receptor had no impact on the HIV inhibition. Lastly, IL-27 mediated inhibition was shown to act post-viral entry and prior to completion of reverse transcription. These results show for the first time that IL-27 is a potent inhibitor of cis HIV-1 infection in DCs by a Type I IFN independent mechanism. IL-27 has previously been reported to inhibit HIV-1 replication in CD4+ T cells and macrophages, thus taken together, this cytokine is a potent anti-HIV agent against all major cell types targeted by the HIV-1 virus and may have a therapeutic role in the future.
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Identification of target genes of transcription factor CEBPB in acute promyelocytic leukemia cells induced by all-trans retinoic acid.
Asian Pac J Trop Med
PUBLISHED: 02-10-2013
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To identify target genes of transcription factor CCAAT enhancer-binding protein ? (CEBPB) in acute promyelocytic leukemia cells induced by all-trans retinoic acid.
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High-Q modes in defected microcircular resonator confined by metal layer for unidirectional emission.
Opt Express
PUBLISHED: 02-08-2013
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Defected circular resonators laterally confined by a metal layer with a flat side as an emitting window are numerically investigated based on the boundary element method for realizing unidirectional emission microlasers. The results indicate that Fabry-Pérot (FP) modes become high Q confined modes in the defected circular resonator with a metallic layer. The mode coupling between the FP mode and chaotic-like mode can result in high Q confined mode for unidirectional emission with a narrow far field pattern.
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Genetic variability of Echinococcus granulosus from the Tibetan plateau inferred by mitochondrial DNA sequences.
Vet. Parasitol.
PUBLISHED: 02-06-2013
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To analyse genetic variability and population structure, 84 isolates of Echinococcus granulosus (Cestoda: Taeniidae) collected from various host species at different sites of the Tibetan plateau in China were sequenced for the whole mitochondrial nad1 (894 bp) and atp6 (513 bp) genes. The vast majority were classified as G1 genotype (n=82), and two samples from human patients in Sichuan province were identified as G3 genotype. Based on the concatenated sequences of nad1+atp6, 28 different haplotypes (NA1-NA28) were identified. A parsimonious network of the concatenated sequence haplotypes showed star-like features in the overall population, with NA1 as the major haplotype in the population networks. By AMOVA it was shown that variation of E. granulosus within the overall population was the main pattern of the total genetic variability. Neutrality indexes of the concatenated sequence (nad1+atp6) were computed by Tajimas D and Fus Fs tests and showed high negative values for E. granulosus, indicating significant deviations from neutrality. FST and Nm values suggested that the populations were not genetically differentiated.
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Clinical efficacy of botanical extracts from Eupatorium adenophorum against the Sarcoptes scabiei (Sarcoptidae: Sarcoptes) in rabbits.
Vet. Parasitol.
PUBLISHED: 02-03-2013
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The aims of present study were to evaluate the therapeutic efficacy of extracts from Eupatorium adenophorum against Sarcoptes scabiei. A 30-day experiment was performed using New Zealand rabbits that were naturally infested with S. scabiei in the toes (n=30) or artificially infected in the external ear margin with S. scabiei (n=30). Rabbits were randomly divided into five groups (6 animals per group, A-E groups for rabbits of naturally infested and F-J groups for artificially infected rabbits), respectively. All 60 rabbits were treated twice on days 0 and 7 successively. Animals in groups A/F, B/G, and C/H were treated on each toe/external ear margin with topical E. adenophorum ethanol extract at 1.0, 0.5 and 0.25 g/ml (w/v), respectively. Animals in groups D/I and E/J were treated with ivermectin by injections (positive controls) or by glycerol with water only rubbed onto the affected area (negative controls). After two treatments with extracts of E. adenophorum with relatively high concentrations of 0.5 and 1g/ml, the S. scabiei was completely eliminated in rabbits between days 14 and 30. Our results showed that rabbits treated with ivermectin (positive controls) and those treated with the extracts of concentrations of 1.0 or 0.5 g/ml achieved remarkable therapeutic efficacy; no mites were present in toes of rabbits in these groups on day 14, which confirmed a 100% therapeutic efficacy rate up to day 30 of the end of the trial. The clinical effects of treatment with 1.0 and 0.5 g/ml E. adenophorum extracts (groups A and B) were similar to ivermectin treatment. However, the therapeutic efficacy in group C and E rabbits only reached 43.25% and 7.13% by day 14. Furthermore, the therapeutic efficacy improved slightly by the end of the experiment on day 30, and rabbits in groups F, G and I also achieved good efficacy according to the recovery scoring criteria. These results indicate that E. adenophorum contains potent compounds for the effective control of sarcoptidosis.
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Clinical significance of microRNA-93 downregulation in human colon cancer.
Eur J Gastroenterol Hepatol
PUBLISHED: 01-29-2013
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MicroRNA-93 (miR-93) has been shown to suppress proliferation and colony formation of colon cancer stem cells. The aim of this study was to examine the expression pattern and prognostic value of miR-93 in patients with colon cancer.
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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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