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Find video protocols related to scientific articles indexed in Pubmed.
Quantitative Proteomics for Cardiac Biomarker Discovery Using Isoproterenol-Treated Nonhuman Primates.
J. Proteome Res.
PUBLISHED: 10-28-2014
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To identify new cardiac biomarkers, a quantitative proteomic analysis has been performed on serum and heart tissue proteins from three species of nonhuman primates following isoproterenol (ISO) treatment. Three serum proteins-serum amyloid A (SAA), ?-1-acid glycoprotein (A1AG), and apolipoprotein A-1 (Apo A1)-were consistently identified as changed and remained altered 72 h post dose in all three species post ISO treatment, indicating the potential of including these proteins in preclinical or clinical evaluation of drug-induced cardiac injury. Furthermore, proteomic analysis of heart tissue proteins following ISO treatment demonstrated detrimental effects on calcium signaling and energy generation in cardiac myocytes. It is worth noting that cardiac troponins were not identified in serum but were identified as altered in heart tissue lysate along with other cardiac-specific proteins. This strategy for cardiac biomarker discovery by proteomic screening of heart tissue proteins, followed by verification in serum samples using immunoassays or targeted mass spectrometry, could be applied in future biomarker studies.
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N,N'-Dioxide-Scandium(III)-Catalyzed Asymmetric Aza-Friedel-Crafts Reaction of Sesamol with Aldimines.
J. Org. Chem.
PUBLISHED: 10-17-2014
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A highly efficient aza-Friedel-Crafts reaction of sesamol with aldimines has been realized by using a chiral N,N'-dioxide-scandium(III) complex as the catalyst. A series of corresponding bioactive chiral ?-amino-sesamols were obtained in moderate to good yields (up to 97%) with excellent enantioselectivities (up to 97% ee). Furthermore, the control experiments were conducted to provide fundamental insights into the mechanism of the reaction.
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Frontispiece: Asymmetric Reduction of ?-Amino Ketones with a KBH4 Solution Catalyzed by Chiral Lewis Acids.
Chemistry
PUBLISHED: 10-08-2014
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Asymmetric Alkali Metal Borohydride Reduction Alkali metal borohydrides are mild, inexpensive, highly selective, and environmentally friendly reducing agents in organic chemistry. In their Communication on page?13482?ff., X. Feng et al. demonstrate an efficient enantioselective reduction of both secondary and primary ?-amino ketones with potassium borohydride solution catalyzed by chiral N,N'-dioxide-metal complex catalysts. The catalytic system features a convenient operation and tolerance to water, without the need for basic additives.
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IAPP-driven metabolic reprogramming induces regression of p53-deficient tumours in vivo.
Nature
PUBLISHED: 09-30-2014
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TP53 is commonly altered in human cancer, and Tp53 reactivation suppresses tumours in vivo in mice (TP53 and Tp53 are also known as p53). This strategy has proven difficult to implement therapeutically, and here we examine an alternative strategy by manipulating the p53 family members, Tp63 and Tp73 (also known as p63 and p73, respectively). The acidic transactivation-domain-bearing (TA) isoforms of p63 and p73 structurally and functionally resemble p53, whereas the ?N isoforms (lacking the acidic transactivation domain) of p63 and p73 are frequently overexpressed in cancer and act primarily in a dominant-negative fashion against p53, TAp63 and TAp73 to inhibit their tumour-suppressive functions. The p53 family interacts extensively in cellular processes that promote tumour suppression, such as apoptosis and autophagy, thus a clear understanding of this interplay in cancer is needed to treat tumours with alterations in the p53 pathway. Here we show that deletion of the ?N isoforms of p63 or p73 leads to metabolic reprogramming and regression of p53-deficient tumours through upregulation of IAPP, the gene that encodes amylin, a 37-amino-acid peptide co-secreted with insulin by the ? cells of the pancreas. We found that IAPP is causally involved in this tumour regression and that amylin functions through the calcitonin receptor (CalcR) and receptor activity modifying protein 3 (RAMP3) to inhibit glycolysis and induce reactive oxygen species and apoptosis. Pramlintide, a synthetic analogue of amylin that is currently used to treat type 1 and type 2 diabetes, caused rapid tumour regression in p53-deficient thymic lymphomas, representing a novel strategy to target p53-deficient cancers.
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Complete mitochondrial genome of Chinese bamboo rat, Rhizomys sinensis and species divergence comparison.
Mitochondrial DNA
PUBLISHED: 09-30-2014
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Abstract The Chinese bamboo rat Rhizomys sinensis belongs to family Spalacidae, and is distributed in China, Myanmar, and Vietnam. In this study, the entire mitochondrial genome of R. sinensis was firstly determined. The genome is 16,564 bases in length, containing 13 protein coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and a putative control region. The composition and arrangement of its genes are identical to most other mammals. The whole base composition of the mitogenome is A 31.9%, G 12.0%, T 31.2% and C 24.9%, with an A+T rich pattern. The species divergence between R. sinensis and R. pruinosus is 0.113, in accordance with a "10× rule", as the intraspecific barcode variation averaged 1%. The mitogenome data of R. sumatrensis is required to better understand the phylogenetic relationships within Rhizomys.
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Newcastle disease virus vaccine encapsulated in biodegradable nanoparticles for mucosal delivery of a human vaccine.
Hum Vaccin Immunother
PUBLISHED: 09-30-2014
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An overwhelming number of medicines on the market are oral medicine with the disadvantage of lower bioavailability universally. Newcastle disease (ND) has become a serious disease that threatens the poultry industries in many countries, and there are no treatments available for ND. The biodegradable materials could be surface modified and protect antigen or DNA from damage. Furthermore, nanoparticles are also a potential drug delivery with proper size. However, Newcastle disease virus (NDV) vaccines encapsulated in nanoparticles were widely used due to their proved a high safety and induced quicker and better mucosal and humoral immune responses. Here we review the results of mucosal immune delivery system for ND. Due to the safety, low toxicity, and better immunogenicity of the mucosal immune delivery system, our studies provide a clearly view that used the biodegradable materials to research and develop the human vaccines to save more patients' lives. These promising results provide a foundation for testing the approach in humans.
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Simultaneous Determination of 10 Components in Bu-Zhong-Yi-Qi Wan by Solid Phase Extraction-High Performance Liquid Chromatography with Diode Array Detection and Evaporative Light Scattering Detection.
J Chromatogr Sci
PUBLISHED: 09-13-2014
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An effective, accurate and reliable method for the simultaneous separation and determination of 10 major components in Chinese medicine Bu-Zhong-Yi-Qi Wan (BZYQW) was developed and validated using solid phase extraction column-high performance liquid chromatography-diode array detection-evaporative light scattering detection (SPE-HPLC-DAD-ELSD). The chromatographic separation was performed on a Spursil™ C18 column (250 mm × 4.6 mm, 5 µm) at 30°C with an acetonitrile-water gradient as mobile phase. The DAD detection wavelength 254 nm was utilized for the quantitative analysis. The drift tube temperature and the carrier gas flow rate of the ELSD detection was set at 110.5°C and 3.1 mL/min. The total run time is 103 min, these determined components peak out within 81 min. Excellent linear behaviors over the investigated concentration ranges were observed with the values of r(2) higher than 0.9990 for all the analytes. The Linear range over hesperidin, senkyunolide I, senkyunolide H, ononin, calycosin, formononetin, ligustilide, butylene phthalide, astragaloside IV, astragaloside I is 4.50-94.50 µg/mL, 22.75-364.00 µg/mL, 2.30-45.00 µg/mL, 11.76-125.14 µg/mL, 4.62-50.35 µg/mL, 1.90-28.93 µg/mL, 1.29-159.00 µg/mL, 2.90-36.00 µg/mL, 35.40-192.40 µg/mL, 41.40-96.60 µg/mL, respectively. The method was validated by its repeatability [relative standard deviation (RSD) < 3.54%] and intra-day (RSD < 2.11%) and inter-day precision (RSD < 3.45%). The limits of detection and quantification of each component were in the ranges of 0.04-10.24 and 0.12-39.22 µg/mL, respectively. The average recovery yields of the 10 compounds ranged from 95.79 to 101.25%. The validated method was successfully applied to the simultaneous determination of these principal components in 10 commercial samples of BZYQW from different manufacturers.
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Enantioselective Construction of Vicinal Tetrasubstituted Stereocenters by the Mannich Reaction of Silyl Ketene Imines with Isatin-Derived Ketimines.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 09-01-2014
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A highly enantioselective Mannich reaction of silyl ketene imines with isatin-derived ketimines has been realized by using a chiral N,N'-dioxide/Zn(II) catalyst. A variety of ?-amino nitriles containing congested vicinal tetrasubstituted stereocenters were obtained with excellent outcomes (up to 98?% yield, >19:1 d.r. and 99?% ee). Based on the experimental investigations, a possible transition state has been proposed to explain the origin of the asymmetric induction.
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Transcriptional regulation of the human TNFSF11 gene in t cells via a cell type-selective set of distal enhancers.
J. Cell. Biochem.
PUBLISHED: 09-01-2014
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In addition to osteoblast lineage cells, the TNF-like factor Receptor Activator of NF-?B ligand (RANKL) is expressed in both B and T cells and may play a role in bone resorption. Rankl expression in mouse T cells is mediated through multiple distal elements marked by increased transcription factor occupancy, histone tail acetylation and RNA polymerase II recruitment. Little is known, however, of the regulation of human RANKL in T cells. Accordingly, we examined the consequence of T cell receptor (TCR) activation on expression of this factor in both Jurkat cells and in primary human T cells. We then explored the mechanism of this regulation by scanning over 400 kb of DNA surrounding the RANKL locus for regulatory enhancers using ChIP-chip analysis. Histone H3/H4 acetylation enrichment identified putative regulatory regions located between -170 and -220 kb upstream of the human RANKL TSS that we designated the human T cell control region (hTCCR). This region showed high sequence conservation with the mouse TCCR. Inhibition of MEK1/2 by U0126 resulted in decreased RANKL expression suggesting that stimulation through MEK1/2 was a prerequisite. ChIP-chip analysis also revealed that c-FOS was recruited to the hTCCR as well. Importantly, both the human RLD5a/b enhancer and segments of the hTCCR mediated robust inducible reporter activity following TCR activation. Finally, SNPs implicated in diseases characterized by dysregulated BMD co-localized to the hTCCR region. We conclude that the hTCCR region contains a cell-selective set of enhancers that plays an integral role in the transcriptional regulation of the TNFSF11 gene in human T cells. J. Cell. Biochem. © 2014 Wiley Periodicals, Inc.
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Image quality and required radiation dose for coronary computed tomography angiography using an automatic tube potential selection technique.
Int J Cardiovasc Imaging
PUBLISHED: 08-29-2014
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To investigate the image quality and the minimum required radiation dose for automatic tube potential selection (ATPS) in dual-source computed tomography (DSCT) coronary computed tomography angiography (CCTA). Three hundred twenty-five consecutive patients (153 men and 172 women) undergoing CCTA were assigned to either the ATPS group (n = 172) or the control group (n = 153); the control group underwent imaging at a constant current of 120 kV. All patients were scanned in either prospectively ECG-triggered high-pitch helical mode or sequential mode. The subjective image quality score, attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), volume CT dose index (CTDIvol), and effective dose (ED) were compared between the two groups with the Student t test or Mann-Whitney U test. The subjective image quality score was not significantly different between the two groups. Imaging noise and attenuation were both significantly higher in the ATPS group than in the control group (imaging noise: 25.6 ± 7.6 versus 15.8 ± 4.0 HU, P < 0.001; attenuation: 559.6 ± 142.0 versus 412.5 ± 64.3 HU, P < 0.001). SNR and CNR were significantly lower in the ATPS group than in the control group (SNR: 23.21 ± 7.40 versus 27.71 ± 8.25, P < 0.001; CNR: 27.81 ± 8.44 versus 33.94 ± 9.69, P < 0.001). ED was significantly lower in the ATPS group than in the control group (ED: 1.25 ± 1.24 versus 2.19 ± 1.77 mSv, P < 0.001). For both groups, ED was significantly lower in the high-pitch mode than in the sequential mode. The use of ATPS for CCTA significantly reduced the radiation dose while maintaining image quality.
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Hollandites as a new class of multiferroics.
Sci Rep
PUBLISHED: 08-27-2014
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Discovery of new complex oxides that exhibit both magnetic and ferroelectric properties is of great interest for the design of functional magnetoelectrics, in which research is driven by the technologically exciting prospect of controlling charges by magnetic fields and spins by applied voltages, for sensors, 4-state logic, and spintronics. Motivated by the notion of a tool-kit for complex oxide design, we developed a chemical synthesis strategy for single-phase multifunctional lattices. Here, we introduce a new class of multiferroic hollandite Ba-Mn-Ti oxides not apparent in nature. BaMn3Ti4O14.25, designated BMT-134, possesses the signature channel-like hollandite structure, contains Mn(4+) and Mn(3+) in a 1:1 ratio, exhibits an antiferromagnetic phase transition (TN ~ 120?K) with a weak ferromagnetic ordering at lower temperatures, ferroelectricity, a giant dielectric constant at low frequency and a stable intrinsic dielectric constant of ~200 (1-100?MHz). With evidence of correlated antiferromagnetic and ferroelectric order, the findings point to an unexplored family of structures belonging to the hollandite supergroup with multifunctional properties, and high potential for developing new magnetoelectric materials.
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An asymmetric [3+2] cycloaddition of alkynes with oxiranes by selective C-C bond cleavage of epoxides: highly efficient synthesis of chiral furan derivatives.
Chem. Commun. (Camb.)
PUBLISHED: 08-19-2014
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An efficient enantioselective [3+2] cycloaddition of alkynes with oxiranes via selective C-C bond cleavage of epoxides was developed. A number of optically active 2,5-dihydrofurans were obtained in excellent yields (up to 99%) and enantioselectivities (up to 95% ee) under mild reaction conditions. Moreover, chiral tetrahydrofuran could also be obtained by cycloaddition of alkene and oxirane or hydrogenation of chiral 2,5-dihydrofuran.
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Influence of tube voltage on digitized image qualityof patients exposed to occupational dust: phantoms and clinical studies.
Chin. Med. J.
PUBLISHED: 08-19-2014
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High-voltage analog X-ray examination is a main tool for pneumoconiosis, which is challenged by digital radiography (DR). The tube voltage of DR chest films required for diagnosis and staging of pneumoconiosis is concerned technically. We investigated the influence of the tube voltage on chest X-ray DR image quality of patients exposed to occupational dust.
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High-level expression and characterization of bioactive human truncated variant of hepatocyte growth factor in Escherichia coli.
World J. Microbiol. Biotechnol.
PUBLISHED: 08-14-2014
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Hepatocyte growth factor (HGF) is an effective anti-fibrotic factor because of its bioactivity in inhibiting fibrosis-related proteins in the development of hepatic fibrosis. However, high-level production of bioactive mature form HGF is difficult because of its complex structure. Here, we report a non-fusion protein expression system to obtain truncated variant of N-terminal hairpin and first kringle domains of HGF (tvNK1) in Escherichia coli to determine its anti-fibrotic effects on hepatic stellate cells (HSCs). Under the selected conditions of cultivation and isopropyl-?-D-1-thiogalactopyranoside induction, the expression level of tvNK1 accounted for approximately 65 % of the total cellular protein and 50 % of fusion protein in the supernatant of whole cell lysates. The recombinant protein could be purified in one step with Ni(2+)-affinity chromatograph. Finally, about 65 mg recombinant tvNK1 was obtained from 1 l fermentation culture with no <95 % purity. In vitro, the final purified tvNK1 was shown to inhibit the proliferation of HSCs and decrease the mRNA and protein expression levels of fibrosis-related COL1A1 and ?-smooth muscle actin genes.
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Asymmetric Reduction of ?-Amino Ketones with a KBH4 Solution Catalyzed by Chiral Lewis Acids.
Chemistry
PUBLISHED: 08-05-2014
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An efficient enantioselective reduction of ?-amino ketones with potassium borohydride solution catalyzed by chiral N,N'-dioxide-metal complex catalysts was accomplished under mild reaction conditions for the first time. It provided a simple, convenient, and practical approaches for obtaining synthetically important chiral ?-amino alcohols in good to excellent yields (up to 98?%) and enantioselectivities (up to 97?%?ee).
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Asymmetric synthesis of spiro-epoxyoxindoles by the catalytic Darzens reaction of isatins with phenacyl bromides.
Org. Lett.
PUBLISHED: 08-04-2014
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The asymmetric Darzens reaction between phenacyl bromides and N-protected isatins was developed to synthesize potentially bioactive spiro-epoxyoxindoles. The optically active products were obtained in moderate to good yields and enantioselectivities catalyzed by chiral N,N'-dioxide-Co(acac)2 complexes. A retro-aldol process accompanying the ring-closure step was observed in the process. A chiral control step was determined to be the initial aldol addition.
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Asymmetric synthesis of spiro[isoxazolin-3,3'-oxindoles] via the catalytic 1,3-dipolar cycloaddition reaction of nitrile oxides.
J. Org. Chem.
PUBLISHED: 08-04-2014
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A highly enantioselective 1,3-dipolar cycloaddition of nitrile oxides with 3-arylidene-oxindoles was realized by a chiral N,N'-dioxide-nickel(II) complex catalyst under mild reaction conditions. A series of spiro-isoxazoline-oxindole derivatives were obtained in moderate yields (up to 65%) with good regioselectivities (up to 99:1), excellent enantioselectivities (up to 99% ee), and exclusive diastereoselectivity as well.
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Asymmetric Synthesis of 2,3-Dihydropyrroles by Ring-Opening/Cyclization of Cyclopropyl Ketones Using Primary Amines.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-02-2014
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The asymmetric ring-opening/cyclization of cyclopropyl ketones with primary amine nucleophiles was catalyzed by a chiral N,N'-dioxide/scandium(III) complex through a kinetic resolution process. A broad range of cyclopropyl ketones and primary amines are suitable substrates of this reaction. The corresponding products were afforded in excellent enantioselectivities and yields (up to 97?% ee and 98?% yield) under mild reaction conditions. This method provides a promising access to chiral 2,3-dihydropyrroles as well as an effective procedure for the kinetic resolution of 2-substituted cyclopropyl ketones.
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Optical design and evaluation of a 4 mm cost-effective ultra-high-definition arthroscope.
Biomed Opt Express
PUBLISHED: 07-18-2014
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High definition and magnification rigid endoscope plays an important role in modern minimally invasive medical surgery and diagnosis. In this paper, we present the design and evaluation methods of a high definition rigid endoscope, specifically an arthroscope, with a large depth of field (DOF). The incident heights and exit angles of the sampled rays on the relay lens are controlled during the optimization process to ensure an effective field view (70°) and a normal ray path within the limited lens diameter of 2.7 mm. The lens is set up as a multi-configuration system with two extreme and one middle object distances to cover a large DOF. As a result, an entrance pupil of 0.3 mm is achieved for the first time, to bring the theoretical resolution to 23.1 lps/mm in the object space at a working distance of 20 mm, with the wavelength of 0.532 um. The modulation transfer function (MTF) curves approach diffraction limit, and the values are all higher than 0.3 at 160 line pairs/mm (lps/mm) in the image space. Meanwhile, stray light caused by total internal reflection on the inner wall of the rod lenses and the objective lens is eliminated. The measured resolution in the object space at a 20 mm working distance is 22.3 lps/mm, and test results show that other performance characteristics also fulfill design requirements. The relay lenses are designed with only one type of the spacer and two types of lenses to greatly reduce the fabrication and assembly cost. The design method has important research and application values for lens systems used in modern minimally invasive medical surgery and industrial non-destructive testing area.
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De novo assembly and characterization of stress transcriptome and regulatory networks under temperature, salt and hormone stresses in Lilium lancifolium.
Mol. Biol. Rep.
PUBLISHED: 07-17-2014
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Plants have continually confrontation with different abiotic stresses, including salt, low temperature, drought or hormone stress. The plants acclimate to the environmental stresses relating with the falls of the molecular mesh including the stress signal receiver, signal transcriptional regulation and the expression of functional and structure genes. Using the RNA-seq, we carried out a transcriptional analysis under cold treatment for investigating a profound comprehension of the signal network and molecular metabolisms reaction included in abiotic stress reaction for Lilium lancifolium. Our study identified 18,722 unigenes had demonstrated the resemblance to the known exact proteins in the Swiss-Prot protein database and classified them by Gene ontology into three primary kinds: cellular component, biological process, and molecular function, and then 15,898 unigenes aligned to existing sequences in the KEGG databases. Based on the transcriptome results of cold stress, more stress-related genes were identified and analyzed of their expressions in other abiotic stress treatments as 37 °C, ABA, JA and Na. Meanwhile, bioinformatics qRT-PCR analyses of stress genes as LlDREB1, LlAP2, LlNAC1, LlHOT, LlR2R3-MYB and LlCDPK revealed that novel candidate genes encoding ethylene responsive transporters and serine/threonine receptor-like kinases, which contributed to speculate the signal regulation pathway during the abiotic stresses; engineering genes could also boost the tolerance to stress, as protected and maintained the function and structure of cellular components. Our research conjectured the abiotic stress signal transduction pathway and identified the expected key ingredients regulating the stress tolerance in Lilium lancifolium, which would enable the in-depth molecular exploration of stress-tolerance mechanisms in lily.
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Greenhouse gas emissions from cotton field under different irrigation methods and fertilization regimes in arid northwestern China.
ScientificWorldJournal
PUBLISHED: 07-16-2014
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Drip irrigation is broadly extended in order to save water in the arid cotton production region of China. Biochar is thought to be a useful soil amendment to reduce greenhouse gas (GHG) emissions. Here, a field study was conducted to compare the emissions of nitrous oxide (N2O) and methane (CH4) under different irrigation methods (drip irrigation (D) and furrow irrigation (F)) and fertilization regimes (conventional fertilization (C) and conventional fertilization + biochar (B)) during the cotton growth season. The accumulated N2O emissions were significantly lower with FB, DC, and DB than with FC by 28.8%, 36.1%, and 37.6%, while accumulated CH4 uptake was 264.5%, 226.7%, and 154.2% higher with DC, DB, and FC than that with FB, respectively. Irrigation methods showed a significant effect on total global warming potential (GWP) and yield-scaled GWP (P < 0.01). DC and DB showed higher cotton yield, water use efficiency (WUE), and lower yield-scaled GWP, as compared with FC and FB. This suggests that in northwestern China mulched-drip irrigation should be a better approach to increase cotton yield with depressed GHG. In addition, biochar addition increased CH4 emissions while it decreased N2O emissions.
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Regio- and enantioselective Baeyer-Villiger oxidation: kinetic resolution of racemic 2-substituted cyclopentanones.
Org. Lett.
PUBLISHED: 07-16-2014
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A kinetic resolution of racemic 2-substituted cyclopentanones via highly regio- and enantioselective Baeyer-Villiger oxidation has been successfully developed. The reaction could afford the normal 6-substituted ?-lactones in up to 98% ee and >19/1 regioselectivity. Meanwhile, the unreacted ketones were recovered in excellent ee values (up to 98%). It represents the best results of the kinetic resolution of racemic 2-substituted cyclopentanones via nonenzymic asymmetric BV oxidation.
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Functional expression, characterization and application of the human S100A4 protein.
Mol Med Rep
PUBLISHED: 07-09-2014
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Preparations utilizing monoclonal antibodies against S100A4 provide useful tools for functional studies to investigate the clinical applications of the human S100A4 protein. In the present study, human S100A4 protein was expressed in Escherichia coli (E. coli) BL21 (DE3), successfully purified by diethylaminoethyl cellulose anion-exchange chromatography and identified by western blot analysis. Soluble S100A4 bioactivity was confirmed by Transwell migration and invasion assays in the human HeLa cell line. Monoclonal antibodies (mAbs) were generated utilizing the standard hybridoma method and were validated by enzyme-linked immunosorbent assay and western blot analysis. The antibody was then used to examine human gastric carcinoma specimens by immunohistochemistry. Recombinant S100A4 was functionally expressed in E. coli and promoted the migration and invasion of HeLa cells. Four hybridoma cell lines, which secreted mAbs specifically against human S100A4 protein, were obtained. One of the four mAbs, namely 2A12D10B2, recognized human S100A4 as indicated by immunohistochemical staining of human gastric carcinoma specimens and recombinant S100A4 was functionally expressed in E. coli. The mAbs of recombinant S100A4 were suitable for detecting S100A4 expression in human tissues and for investigating the subsequent clinical applications of the protein.
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Asymmetric Hetero-Diels-Alder Reaction of Danishefsky's Diene with ?-Ketoesters and Isatins Catalyzed by a Chiral N,N'-Dioxide/Magnesium(II) Complex.
Chemistry
PUBLISHED: 06-26-2014
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A highly enantioselective hetero-Diels-Alder reaction of Danishefsky's diene with ?-ketoesters and isatins has been realized by using a chiral N,N'-dioxide/Mg(II) complex. In the presence of only 0.1-0.5?mol?% catalyst, a series of substrates were transformed into the corresponding tetrasubstituted 2,3-dihydropyran-4-ones in up to 99?% yield and more than 99?%?ee in two hours.
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Efficient synthesis of carbazolespirooxindole skeletons via asymmetric Diels-Alder reaction of 3-vinylindoles and methyleneindolinones.
Chem. Commun. (Camb.)
PUBLISHED: 06-26-2014
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A highly efficient catalytic asymmetric Diels-Alder reaction between 3-vinylindoles and methyleneindolinones has been achieved using chiral N,N'-dioxide-Ni(II) complexes as the catalysts. A wide variety of substrates were readily tolerated, generating exclusively the corresponding exo-carbazolespirooxindole derivatives in excellent yields with high enantiomeric excesses (up to 98% yield, >99?:?1 d.r., and 98% ee) under mild reaction conditions.
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Analysis of the leaf methylomes of parents and their hybrids provides new insight into hybrid vigor in Populus deltoides.
BMC Genet.
PUBLISHED: 06-20-2014
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Plants with heterosis/hybrid vigor perform better than their parents in many traits. However, the biological mechanisms underlying heterosis remain unclear. To investigate the significance of DNA methylation to heterosis, a comprehensive analysis of whole-genome DNA methylome profiles of Populus deltoides cl.'55/65' and '10/17' parental lines and their intraspecific F1 hybrids lines was performed using methylated DNA immunoprecipitation (MeDIP) and high-throughput sequencing.
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Transcriptome sequencing of transgenic poplar (Populus × euramericana 'Guariento') expressing multiple resistance genes.
BMC Genet.
PUBLISHED: 06-20-2014
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Transgenic poplar (Populus × euramericana 'Guariento') plants harboring five exogenous, stress-related genes exhibit increased tolerance to multiple stresses including drought, salt, waterlogging, and insect feeding, but the complex mechanisms underlying stress tolerance in these plants have not been elucidated. Here, we analyzed the differences in the transcriptomes of the transgenic poplar line D5-20 and the non-transgenic line D5-0 using high-throughput transcriptome sequencing techniques and elucidated the functions of the differentially expressed genes using various functional annotation methods.
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[Sequence analyses of HIRA gene 3'UTR region and related microRNA].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 06-14-2014
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To explore the HIRA gene sequences of 3'UTR region and elucidate the role of 3'UTR region of HIRA gene in the pathogenesis of tetralogy of Fallot (TOF).
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Thermal diffusion desorption for the comprehensive analysis of organic compounds.
Anal. Chem.
PUBLISHED: 06-10-2014
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Comprehensive analysis of organic compounds is crucial yet challenging considering that information on elements, fragments, and molecules is unavailable simultaneously by current analytical techniques. Additionally, many compounds are insoluble or only dissolve in toxic solvents. A solvent- and matrix-free strategy has been developed which allows the organic compound analyzed in its original form. It utilizes thermal diffusion desorption with the solid analyte irradiated with high energy laser. It is capable of providing explicit elemental, fragmental, and molecular information simultaneously for a variety of organic compounds. Thermal diffusion desorption has many advantages compared to the electrospray and MALDI techniques. The protons that form the protonated molecular ions originate from the analyte itself. All the elements and fragments are also derived from the analyte itself, which provides abundant information and expedites the identification of organic compounds.
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Catalytic hetero-ene reactions of 5-methyleneoxazolines: highly enantioselective synthesis of 2,5-disubstituted oxazole derivatives.
Chem. Commun. (Camb.)
PUBLISHED: 06-04-2014
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An efficient catalytic asymmetric hetero-ene reaction of 5-methyleneoxazolines with 1,2-dicarbonyl compounds (including ?-ketoesters and glyoxal derivatives) was realized using Ni(II)-N,N'-dioxide complexes as the catalysts. It provides a rapid, high yielding (up to 99%) route for the preparation of 2,5-disubstituted oxazole derivatives in a highly enantioenriched form (up to >99% ee) under mild conditions.
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N,N'-Dioxide/Nickel(II)-Catalyzed Asymmetric Inverse-Electron-Demand Hetero-Diels-Alder Reaction of ?,?-Unsaturated ?-Ketoesters with Enecarbamates.
Chemistry
PUBLISHED: 05-31-2014
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N,N'-Dioxide/nickel(II) complexes have been developed to catalyze the inverse-electron-demand hetero-Diels-Alder reaction of ?,?-unsaturated ?-ketoesters with acyclic enecarbamates. After detailed screening of the reaction parameters, mild optimized reaction conditions were established, affording 3,4-dihydro-2H-pyranamines in up to 99?% yield, 99?% ee and more than 95:5 d.r. The catalytic system was also efficient for ?-substituted acyclic enecarbamates, affording more challenging 2,3,4-trisubstituted 3,4-dihydro-2H-pyranamine with three contiguous stereogenic centers in excellent yields, diastereoselectivities, and enantioselectivities. The reaction could be scaled up to a gram scale with no deterioration of either enantioselectivity or yield. Based on these experiments and on previous reports, a possible transition state was proposed.
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A source of the single-stranded DNA substrate for activation-induced deaminase during somatic hypermutation.
Nat Commun
PUBLISHED: 05-16-2014
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During somatic hypermutation (SHM), activation-induced deaminase (AID) mutates deoxycytidine on single-stranded DNA (ssDNA) generated by the transcription machinery, but the detailed mechanism remains unclear. Here we report a higher abundance of RNA polymerase II (Pol II) at the immunoglobulin heavy-chain variable (Igh-V) region compared with the constant region and partially transcribed Igh RNAs, suggesting a slower Pol II progression at Igh-V that could result in some early/premature transcription termination after prolonged pausing/stalling of Pol II. Knocking down RNA-exosome complexes, which could decrease premature transcription termination, leads to decreased SHM. Knocking down Spt5, which can augment premature transcription termination, leads to increase in both, SHM and the abundance of ssDNA substrates. Collectively, our data support the model that, following the reduction of Pol II progression (pausing or stalling) at the Igh-V, additional steps such as premature transcription termination are involved in providing ssDNA substrates for AID during SHM.
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Utilization of International Association of Diabetes and Pregnancy Study Groups criteria vs. a two-step approach to screening for gestational diabetes mellitus in Chinese women with twin pregnancies.
Diabet. Med.
PUBLISHED: 05-09-2014
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To evaluate prevalence and pregnancy outcomes using the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria and screening protocol vs. a standard two-step screening approach for gestational diabetes mellitus in Chinese twin pregnancies.
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Vernalization of Oriental hybrid lily 'Sorbonne': changes in physiology metabolic activity and molecular mechanism.
Mol. Biol. Rep.
PUBLISHED: 04-28-2014
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Oriental hybrid lily 'Sorbonne' was used to investigate molecular changes during the storage at 4 °C for dormancy-release besides physiology metabolic activity observations. In physiological mechanism, endogenous abscisic acid (ABA) concentration level of lily bulbs decreased as the cold preservation time increased, and it kept at a stable level after being preserved for 35 days. The level of soluble sugars concentrations also changed during the cold preservation time, and it increased as the cold preservation time raised to 49 days then decreased afterward. On molecule level, a new transcriptome providing comprehensive sequence profiling data of variation during dormancy-release in lily was constructed. 34,367 unigenes expressed differentially between the control and the treatment was analyzed. 14 genes including 8 MADS-box family genes, 4 genes related to plant hormone, and 2 DNA methylation genes were selected to identify the levels of their expression by qRT-PCR. Our results show that the decrease of ABA level during cold storage, as well as changes in plant hormone genes was correlated with dormancy-release; MADS-box family genes VRN2, FLC, FT, SOC1 a, as well as LFY, MIKC and ARF, MYB transcription factor were included in lily floral induction and DNA methylation was correlated to lily vernalization under low temperature. According to the results of the present studies, we predicted that plant hormone pathway, energy metabolic pathway, vernalization pathway, and DNA methylation played important roles during vernalization; these data provided the foundation for future studies of vernalization to induce flowering of lily.
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Kinetic resolution of racemic mandelic Acid esters by n,n'-dioxide-scandium-complex-catalyzed enantiomer-selective acylation.
Chemistry
PUBLISHED: 04-25-2014
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A simple and efficient acylative kinetic resolution of racemic mandelic acid esters was accomplished with a chiral N,N'-dioxide-scandium(III) complex under mild and base-free reaction conditions. A variety of mandelic acid esters performed well in the reaction, obtaining both acylated products (up to 49% yield, 97% ee) and recovered substrates (up to 49% yield, 95% ee) in high enantioselectivities with perfect selectivity factors (up to 247). The enantioselective recognition and catalytic models were also proposed for the catalytic KR reaction.
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Nickel(II)-Catalyzed Asymmetric Propargyl and Allyl Claisen Rearrangements to Allenyl- and Allyl-Substituted ?-Ketoesters.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 04-24-2014
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Highly efficient catalytic asymmetric Claisen rearrangements of O-propargyl ?-ketoesters and O-allyl ?-ketoesters have been accomplished under mild reaction conditions. In the presence of the chiral N,N'-dioxide/Ni(II) complex, a wide range of allenyl/allyl-substituted all-carbon quaternary ?-ketoesters was obtained in generally good yield (up to 99?%) and high diastereoselectivity (up to 99:1 d.r.) with excellent enantioselectivity (up to 99?% ee).
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Blood-based gene-expression biomarkers of post-traumatic stress disorder among deployed marines: A pilot study.
Psychoneuroendocrinology
PUBLISHED: 04-14-2014
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The etiology of post-traumatic stress disorder (PTSD) likely involves the interaction of numerous genes and environmental factors. Similarly, gene-expression levels in peripheral blood are influenced by both genes and environment, and expression levels of many genes show good correspondence between peripheral blood and brain tissues. In that context, this pilot study sought to test the following hypotheses: (1) post-trauma expression levels of a gene subset in peripheral blood would differ between Marines with and without PTSD; (2) a diagnostic biomarker panel of PTSD among high-risk individuals could be developed based on gene-expression in readily assessable peripheral blood cells; and (3) a diagnostic panel based on expression of individual exons would surpass the accuracy of a model based on expression of full-length gene transcripts. Gene-expression levels in peripheral blood samples from 50 U.S. Marines (25 PTSD cases and 25 non-PTSD comparison subjects) were determined by microarray following their return from deployment to war-zones in Iraq or Afghanistan. The original sample was carved into training and test subsets for construction of support vector machine classifiers. The panel of peripheral blood biomarkers achieved 80% prediction accuracy in the test subset based on the expression of just two full-length transcripts (GSTM1 and GSTM2). A biomarker panel based on 20 exons attained an improved 90% accuracy in the test subset. Though further refinement and replication of these biomarker profiles are required, these preliminary results provide proof-of-principle for the diagnostic utility of blood-based mRNA-expression in PTSD among trauma-exposed individuals.
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Altered brain network modules induce helplessness in major depressive disorder.
J Affect Disord
PUBLISHED: 03-17-2014
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The abnormal brain functional connectivity (FC) has been assumed to be a pathophysiological aspect of major depressive disorder (MDD). However, it is poorly understood, regarding the underlying patterns of global FC network and their relationships with the clinical characteristics of MDD.
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Evidence for ion-ion interactions between peptides and anions (HSO?? or ClO??) derived from high-acidity acids.
J Mass Spectrom
PUBLISHED: 03-08-2014
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The existence of gas-phase electrostatic ion-ion interactions between protonated sites on peptides ([Glu] Fibrinopeptide B, Angiotensin I and [Asn(1), Val(5)]-Angiotensin II) and attaching anions (ClO4(-) and HSO4(-)) derived from strong inorganic acids has been confirmed by CID MS/MS. Evidence for ion-ion interactions comes especially from the product ions formed during the first dissociation step, where, in addition to the expected loss of the anion or neutral acid, other product ions are also observed that require covalent bond cleavage (i.e. H2O loss when several carboxylate groups are present, or NH3 loss when only one carboxylate group is present). For [[Glu] Fibrinopeptide B?+?HSO4](-), under CID, H2O water loss was found to require less energy than H2SO4 departure. This indicates that the interaction between HSO4(-) and the peptide is stronger than the covalent bond holding the hydroxyl group, and must be an ion-ion interaction. The strength and stability of this type of ion-pairing interaction are highly dependent on the accessibility of additional mobile charges to the site. Positive mobile charges such as protons from the peptide can be transferred to the attaching anion to possibly form a neutral that may depart from the complex. Alternatively, an ion-ion interaction can be disrupted by a competing proximal additional negatively charged site of the peptide that can potentially form a salt bridge with the positively charged site and thereby facilitate the attaching anion's departure.
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Lily breeding by using molecular tools and transformation systems.
Mol. Biol. Rep.
PUBLISHED: 03-07-2014
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In our review, we highlighted the progresses made in molecular breeding of lily's flowering, including the ABCDE models, the gene cloning, the establishment of regeneration system, the gene transformation methods, the transgene technology application in lily. Meanwhile, questions that were met at present in molecular breeding in flowering of lily were underlined, and we provide viable solutions. Although many researches on lily literature had been published in the world, in our review, we provided a valuable and unique resource and spring-board from which to understand or further study the molecular breeding in flowering of lily.
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Joint power and multiple access control for wireless mesh network with Rose projection method.
ScientificWorldJournal
PUBLISHED: 02-27-2014
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This paper investigates the utility maximization problem for the downlink of the multi-interface multichannel wireless mesh network with orthogonal frequency division multiple access. A cross-layer joint power and multiple access control algorithm are proposed. Rosen projection matrix is combined with Solodov projection techniques to build a three-memory gradient Rosen projection method, which is applied to solve this optimization problem. The convergence analysis is given and simulations show that the proposed solution achieves significant throughput compared with existing approaches.
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Functionally active rat S100A4 from a polymerase chain reaction-synthesized gene expressed in soluble form in Escherichia coli.
Oncol Lett
PUBLISHED: 02-11-2014
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S100A4 protein is associated with Ca(2+)-dependent regulation of intracellular activities and is significant in the invasion, growth and metastasis of cancer. In order to express rat S100A4 functionally and identify its biological activity following purification, an S100A4 gene fragment was optimized and fully synthesized via overlapping polymerase chain reaction. The gene was inserted into the prokaryotic expression vector, pBV220, with phage ? PRPL promoters following confirmation by DNA sequencing. The pBV220-S100A4 plasmid was constructed and transformed into Escherichia coli DH5?. Following temperature induction, rat S100A4 was overexpressed and the protein was observed to be located in the supernatant of the lysates, which was ~30-40% of the total protein within the host. The protein was isolated and purified by metal-chelate affinity chromatography. High purity protein (>98% purity) was obtained and in vitro western blot analysis identified that the recombinant S100A4 was able to bind to the antibody against wild-type S100A4. The bioactivity of the recombinant protein was detected via Transwell migration and invasion assays. The polyclonal antibody of rat S100A4 protein was prepared for rabbit immunization and exhibited similar efficacies when compared with commercial S100A4. Therefore, rat S100A4 was functionally expressed in E. coli; thus, the production of active recombinant S100A4 protein in E. coli may further aid with the investigation and application of S100A4.
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Experimental study on Qizhu formula for modulating survivin, an inhibitor of apoptosis, in MGC-803 gastric cancer cells.
Mol Clin Oncol
PUBLISHED: 02-06-2014
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The aim of this study was to investigate the mechanism of action of Qizhu formula, a Chinese medicinal empirical formula, in modulating the action of survivin, an inhibitor of apoptosis, in MGC-803 gastric cancer cells. Western blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) were applied to detect the effect of varying concentrations of Qizhu formula in the modulation of the expression of survivin in MGC-803 human gastric adenocarcinoma cells. The western blot analysis results demonstrated that Qizhu formula exerted no significant effects on the protein expression of the ?-actin housekeeping gene, whereas it exerted a significant inhibitory effect on the protein expression of the apoptosis-related survivin gene at concentrations of 250 ?g/ml and, particularly, 500 ?g/ml. RT-PCR was used to detect the effect of Qizhu formula on survivin mRNA in MGC-803 human gastric adenocarcinoma cells. The ratio of survivin/?-actin in the 0.1% dimethylsulfoxide and the 125, 250 and 500 ?g/ml groups of Qizhu formula was 0.4543, 0.4025, 0.2415 and 0.2235, respectively. Therefore, Qizhu formula exerted a distinct inhibitory effect on the mRNA expression of survivin in MGC-803 cells in a dose-dependent manner. In conclusion, Qizhu formula may modulate the apoptosis of MGC-803 human gastric adenocarcinoma cells, which is associated with the downregulation of survivin mRNA and protein expression.
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Decreased serum fibroblast growth factor - 2 levels in pre- and post-treatment patients with major depressive disorder.
Neurosci. Lett.
PUBLISHED: 01-26-2014
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Increasing evidence indicates that neurotrophic factor dysfunction might be involved in the pathophysiology and treatment of major depressive disorder (MDD). Fibroblast growth factor (FGF)-2, one of the major neurotrophins, plays an important role in the central nervous system (CNS). The aim of this study was to explore whether the FGF-2 in serum was associated with MDD and to evaluate the effects of antidepressant treatment on serum FGF-2 levels. Serum FGF-2 levels were determined in 28 pre- and post-treatment MDD patients and 30 healthy controls using ELISA. The results of the current study revealed that serum FGF-2 levels in MDD patients were significantly lower than those in healthy controls (p=0.005), and the serum FGF-2 levels decreased significantly but marginally following treatment for 8 weeks (p=0.005). These findings demonstrate that the lower serum FGF-2 levels contribute to the pathophysiology of MDD and that FGF-2 may be used as a peripheral biological marker for MDD.
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Inhibition of transient receptor potential melastatin 7 (TRPM7) channel induces RA FLSs apoptosis through endoplasmic reticulum (ER) stress.
Clin. Rheumatol.
PUBLISHED: 01-23-2014
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Transient receptor potential melastatin 7 (TRPM7) is involved in both normal physiological processes and pathology of various diseases. The purpose of this study was to explore the function and underlying mechanisms of TRPM7 channels in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLSs) apoptosis induced by thapsigargin in vitro. In this study, using a combination of Western blotting, RT-PCR, and nuclear morphology analysis, we investigated the influence and potential function of TRPM7 channels on the apoptosis induced by thapsigargin in RA FLSs. Chemical inhibitors (Gd(3+) and 2-APB) and specific siRNA for TRPM7 were used to study the role of TRPM7 in RA FLSs apoptosis. The expression of TRPM7 was significantly potentiated in RA FLSs. Co-incubation of RA FLSs with Gd(3+), 2-APB, or TRPM7-siRNA increased cell apoptosis. Furthermore, we found that suppression of TRPM7 channels also increased the expression CHOP and calpain and decreased the expression caspase-3. We conclude that suppression of TRPM7 channels may increase RA FLSs apoptosis in vitro, and this is associated with endoplasmic reticulum (ER) stress. Therefore, inhibition of TRPM7 could activate ER stress and induce RA FLSs apoptosis.
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An in situ immobilized pipette tip solid phase microextraction method based on molecularly imprinted polymer monolith for the selective determination of difenoconazole in tap water and grape juice.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-22-2014
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A pipette tip-based molecularly imprinted polymer monolith microextraction (PT-MIPMME) method was developed for the selective extraction of difenoconazole in tap water and grape juice. In this method, molecularly imprinted polymer (MIP) monolith used as the sorbent was synthesized at the tip of a micropipette. This in situ polymerization reaction used difenoconazole as the template and methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linker and the mixture of toluene-dodecanol as the porogenic solvent. The pipette tip containing MIP monolith was matched to a syringe for performing the polymer monolith microextraction (PMME). Several parameters affecting the proposed PT-MIPMME method were investigated, including the flow rate, sample volume, pH and salt concentration of sample, the type and volume of eluent. Under the optimal conditions, the PT-MIPMME method showed a low limit of detection of 0.5?gL(-1). The recoveries were in the range of 87.6-95.4% with relative standard deviations less than 4.9%. The results showed that difenoconazole was selectively enriched from tap water and grape juice samples.
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Induced multipotency in adult keratinocytes through down-regulation of ?Np63 or DGCR8.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-21-2014
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The roles of microRNAs (miRNAs) and the miRNA processing machinery in the regulation of stem cell biology are not well understood. Here, we show that the p53 family member and p63 isoform, ?Np63, is a transcriptional activator of a cofactor critical for miRNA processing (DGCR8). This regulation gives rise to a unique miRNA signature resulting in reprogramming cells to multipotency. Strikingly, ?Np63(-/-) epidermal cells display profound defects in terminal differentiation and express a subset of markers and miRNAs present in embryonic stem cells and fibroblasts induced to pluripotency using Yamanaka factors. Moreover, ?Np63(-/-) epidermal cells transduced with an inducible DGCR8 plasmid can differentiate into multiple cell fates in vitro and in vivo. We found that human primary keratinocytes depleted of ?Np63 or DGCR8 can be reprogrammed in 6 d and express a unique miRNA and gene expression signature that is similar but not identical to human induced pluripotent stem cells. Our data reveal a role for ?Np63 in the transcriptional regulation of DGCR8 to reprogram adult somatic cells into multipotent stem cells.
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Human hepatocytes with drug metabolic function induced from fibroblasts by lineage reprogramming.
Cell Stem Cell
PUBLISHED: 01-14-2014
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Obtaining fully functional cell types is a major challenge for drug discovery and regenerative medicine. Currently, a fundamental solution to this key problem is still lacking. Here, we show that functional human induced hepatocytes (hiHeps) can be generated from fibroblasts by overexpressing the hepatic fate conversion factors HNF1A, HNF4A, and HNF6 along with the maturation factors ATF5, PROX1, and CEBPA. hiHeps express a spectrum of phase I and II drug-metabolizing enzymes and phase III drug transporters. Importantly, the metabolic activities of CYP3A4, CYP1A2, CYP2B6, CYP2C9, and CYP2C19 are comparable between hiHeps and freshly isolated primary human hepatocytes. Transplanted hiHeps repopulate up to 30% of the livers of Tet-uPA/Rag2(-/-)/?c(-/-) mice and secrete more than 300 ?g/ml human ALBUMIN in vivo. Our data demonstrate that human hepatocytes with drug metabolic function can be generated by lineage reprogramming, thus providing a cell resource for pharmaceutical applications.
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Protective Effects of Social Support Content and Support Source on Depression and Its Prevalence 6?Months after Wenchuan Earthquake.
Stress Health
PUBLISHED: 01-12-2014
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A magnitude 8.0 earthquake struck China's southwestern Sichuan province on 12 May 2008. The reported rates of depression symptoms across studies were not consistent, and its protective factors were unknown. This study collected data from Wenchuan earthquake survivors to estimate the prevalence of depression and explore the protective effects of social support and support source on depression. A randomized sampling cross-sectional survey based on community was conducted in January 2009, in Mianzhu and Anxian counties, and 633 survivors were entered into the study. The Chinese edition of the Center for Epidemiologic Studies Depression Scale and the Social Support Rating Scale were used to investigate depression and social support. The prevalence of probable depression in adults 6?months after the Wenchuan earthquake was 22.9% (145/633). Total social support, subjective support, support use and support from family members, neighbours and organizations negatively predicted depression. According to the results, depression was common 6?months after this major disaster. Total social support, subjective support, support use and support from family members, neighbours and organizations were all protective factors for depression after a major disaster. Copyright © 2014 John Wiley & Sons, Ltd.
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Post-traumatic stress disorder among adult survivors of the Wenchuan earthquake in China: a repeated cross-sectional study.
J Anxiety Disord
PUBLISHED: 01-07-2014
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The objective of the study was to examine trends in the prevalence of Posttraumatic Stress Disorder (PTSD) in Wenchuan, China, over the four-year period following its 2008 earthquake, and to explore the risk factors related to current PTSD. Chi-square analysis and multivariate logistic regression analysis were used to assess PTSD morbidity and identify associated risk factors. The results indicated that the prevalence of PTSD was 58.2% at two months, 22.10% at 8 months, 19.8% at 14 months, 19.0% at 26 months, and 8.0% at about 44 months after the earthquake. Female gender, being married, low education, non-drinking, and poor self-perceived health status were significantly associated with PTSD during the early period following the earthquake. Depression was significantly associated with survivors' PTSD throughout the study period.
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The incidence of acute myocardial infarction in relation to overweight and obesity: a meta-analysis.
Arch Med Sci
PUBLISHED: 01-05-2014
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Epidemiological evidence suggests that overweight and obesity have been associated with acute myocardial infarction (AMI). However, data on this issue are controversial. This study aims to use meta-analysis to determine whether overweight and obesity are related to AMI.
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Impact of Emphysema Heterogeneity on Pulmonary Function.
PLoS ONE
PUBLISHED: 01-01-2014
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To investigate the association between emphysema heterogeneity in spatial distribution, pulmonary function and disease severity.
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A High-Density Genetic Map Identifies a Novel Major QTL for Boron Efficiency in Oilseed Rape (Brassica napus L.).
PLoS ONE
PUBLISHED: 01-01-2014
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Low boron (B) seriously limits the growth of oilseed rape (Brassica napus L.), a high B demand species that is sensitive to low B conditions. Significant genotypic variations in response to B deficiency have been observed among B. napus cultivars. To reveal the genetic basis for B efficiency in B. napus, quantitative trait loci (QTLs) for the plant growth traits, B uptake traits and the B efficiency coefficient (BEC) were analyzed using a doubled haploid (DH) population derived from a cross between a B-efficient parent, Qingyou 10, and a B-inefficient parent, Westar 10. A high-density genetic map was constructed based on single nucleotide polymorphisms (SNPs) assayed using Brassica 60 K Infinium BeadChip Array, simple sequence repeats (SSRs) and amplified fragment length polymorphisms (AFLPs). The linkage map covered a total length of 2139.5 cM, with 19 linkage groups (LGs) and an average distance of 1.6 cM between adjacent markers. Based on hydroponic evaluation of six B efficiency traits measured in three separate repeated trials, a total of 52 QTLs were identified, accounting for 6.14-46.27% of the phenotypic variation. A major QTL for BEC, qBEC-A3a, was co-located on A3 with other QTLs for plant growth and B uptake traits under low B stress. Using a subset of substitution lines, qBEC-A3a was validated and narrowed down to the interval between CNU384 and BnGMS436. The results of this study provide a novel major locus located on A3 for B efficiency in B. napus that will be suitable for fine mapping and marker-assisted selection breeding for B efficiency in B. napus.
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Chitosan-coated poly(lactic-co-glycolic) acid nanoparticles as an efficient delivery system for Newcastle disease virus DNA vaccine.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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We determined the efficacy and safety of chitosan (CS)-coated poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) as a delivery system for a vaccine to protect chickens against Newcastle disease virus (NDV). The newly constructed vaccine contained DNA (the F gene) of NDV. The Newcastle disease virus (NDV) F gene deoxyribonucleic acid (DNA) plasmid (pFDNA)-CS/PLGA-NPs were spherical (diameter =699.1 ± 5.21 nm [mean ± standard deviation]) and smooth, with an encapsulation efficiency of 98.1% and a Zeta potential of +6.35 mV. An in vitro release assay indicated that CS controlled the burst release of plasmid DNA, such that up to 67.4% of the entire quantity of plasmid DNA was steadily released from the pFDNA-CS/PLGA-NPs. An in vitro expression assay indicated that the expression of nanoparticles (NPs) was maintained in the NPs. In an immunization test with specific pathogen-free chickens, the pFDNA-CS/PLGA-NPs induced stronger cellular, humoral, and mucosal immune responses than the plasmid DNA vaccine alone. The pFDNA-CS/PLGA-NPs did not harm 293T cells in an in vitro assay and did not harm chickens in an in vivo assay. Overall, the results indicated that CS-coated PLGA NPs can serve as an efficient and safe mucosal immune delivery system for NDV DNA vaccine.
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Fabrication of mAb G250-SPIO molecular magnetic resonance imaging nanoprobe for the specific detection of renal cell carcinoma in vitro.
PLoS ONE
PUBLISHED: 01-01-2014
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Molecular magnetic resonance imaging (mMRI) has been paid more and more attention for early diagnosis of cancer. A sensitive and specific mMRI probe plays the most important role in this technique. In this study, superparamagnetic iron oxide (SPIO) nanoparticles and mAb G250 were conjugated as mMRI probe for the detection of clear cell renal cell carcinoma (ccRCC) using 3.0-Tesla MRI in vitro. mAb G250 could specifically recognize carbonic anhydrase IX (CAIX) antigen overexpressed in ccRCC and the SPIO nanoparticles as MRI contrast agent presented excellent MRI response and good biocompatibility. The successful assembly of this nanoprobe was confirmed by UV-vis spectrum, FT-IR spectroscopy and DLS analysis. In vitro MRI study on ccRCC cells and control cells indicated that our fabricated mAb G250-SPIO nanoprobe could be used in the specific labeling of clear cell renal carcinoma cells successfully.
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Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).
PLoS ONE
PUBLISHED: 01-01-2014
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Environmental stresses such as low temperature, drought, and high salinity significantly affect plant growth and yield. As selective forces, these adverse factors play essential roles in shaping phenotypic variation in plant populations. Black poplar (Populus nigra) is an economically and ecologically important forest tree species with widely distributed populations and is thus suitable for experiments detecting evolutionary footprints left by stress. Here, we performed expression and evolutionary analysis of two duplicated DREB A1-subgroup (DREB1) genes, PnDREB68 and PnDREB69, encoding transcription factors that are involved in stress responses. The two genes showed partially overlapping but distinct expression patterns in response to stresses. These genes were strongly and rapidly induced by cold stress in leaves, stems, and roots. In leaf tissue, dehydration stress induced the expression of PnDREB68 but not PnDREB69. PnDREB69 displayed more rapid responses and longer expression durations than PnDREB68 under salt and ABA stress, respectively. Based on single nucleotide polymorphism (SNP) analysis, we found significant population genetic differentiation, with a greater FST value (0.09189) for PnDREB69 than for PnDREB68 (0.07743). Nucleotide diversity analysis revealed a two-fold higher ?T for PnDREB68 than for PnDREB69 (0.00563 vs. 0.00243), reflecting strong purifying selection acting on the former. The results suggest that positive selection acted on PnDREB69, as evidenced by neutral testing using Tajima's D statistic. The distinct selective forces to which each of the genes was subjected may be associated with expression divergence. Linkage disequilibrium (LD) was low for the sequenced region, with a higher level for PnDREB68 than for PnDREB69. Additionally, analysis of the relationship among carbon isotope ratios, SNP classes and gene expression, together with motif and domain analysis, suggested that 14 polymorphisms within the two genes may be candidates for an association study of important traits such as water use efficiency/drought tolerance in black poplar.
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Nerve growth factor variations in patients with mood disorders: no changes in eight weeks of clinical treatment.
Neuropsychiatr Dis Treat
PUBLISHED: 01-01-2014
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Nerve growth factor (NGF) has received much attention for its role in mood disorders. The primary objective of the present study was to examine serum NGF levels in Chinese inpatients with depressive or manic episodes in the acute phase and to explore the changes in NGF levels after effective clinical treatments.
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Efficiently engineered cell sheet using a complex of polyethylenimine-alginate nanocomposites plus bone morphogenetic protein 2 gene to promote new bone formation.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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Regeneration of large bone defects is a common clinical problem. Recently, stem cell sheet has been an emerging strategy in bone tissue engineering. To enhance the osteogenic potential of stem cell sheet, we fabricated bone morphogenetic protein 2 (BMP-2) gene-engineered cell sheet using a complex of polyethylenimine-alginate (PEI-al) nanocomposites plus human BMP-2 complementary(c)DNA plasmid, and studied its osteogenesis in vitro and in vivo. PEI-al nanocomposites carrying BMP-2 gene could efficiently transfect bone marrow mesenchymal stem cells. The cell sheet was made by culturing the cells in medium containing vitamin C for 10 days. Assays on the cell culture showed that the genetically engineered cells released the BMP-2 for at least 14 days. The expression of osteogenesis-related gene was increased, which demonstrated that released BMP-2 could effectively induce the cell sheet osteogenic differentiation in vitro. To further test the osteogenic potential of the cell sheet in vivo, enhanced green fluorescent protein or BMP-2-producing cell sheets were treated on the cranial bone defects. The results indicated that the BMP-2-producing cell sheet group was more efficient than other groups in promoting bone formation in the defect area. Our results suggested that PEI-al nanocomposites efficiently deliver the BMP-2 gene to bone marrow mesenchymal stem cells and that BMP-2 gene-engineered cell sheet is an effective way for promoting bone regeneration.
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Natural variation and genetic analysis of the tiller angle gene MsTAC1 in Miscanthus sinensis.
Planta
PUBLISHED: 01-01-2014
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Biomass yield is an important target trait in Miscanthus breeding for desirable energy crops. Tiller angle is a key trait of plant architecture because it determines planting density and further influences biomass yield through affecting photosynthesis efficiency. TAC1, a major gene involved in tiller and leaf angle control in rice and maize, respectively, has been extensively studied. Nucleotide variation at this gene, MsTAC1, was investigated in 33 Miscanthus sinensis accessions collected from different areas in China, and one genotype of Miscanthus × giganteus. A total of 136 loci, including 129 single base substitutions and seven InDels, occurred within the MsTAC1 gene of 1,874 bp. The genetic diversity at MsTAC1 is characterized by high nucleotide diversity (? value) and high heterozygosity. Clustering analysis indicated that the phylogenetic tree of the 33 M. sinensis accessions was correlated with their geographical sites of origin. The neutrality test revealed no strong selection pressure on coding and non-coding region variations of the MsTAC1 gene in the accessions. Phenotype evaluations were conducted for tiller angle and five other traits in the Miscanthus panels in the first two growth years of 2009 and 2010. Analysis of variance showed significant phenotypic variations in the examined traits. Association analysis using 246 markers detected 88 loci associated with all the test traits in either 1 or 2 years, and 11 of the 88 were year reproducible and thus reliable. These associations indicate that the variation of MsTAC1 affects the phenotypic value of the tiller angle, tiller number and biomass yield, suggesting that allelic variation in MsTAC1 affects multiple traits and demonstrates its significance in Miscanthus breeding programs.
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Meta-analysis of interactions between arbuscular mycorrhizal fungi and biotic stressors of plants.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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Naturally, simultaneous interactions occurred among plants, herbivores, and soil biota, that is, arbuscular mycorrhizal fungi (AMF), nematodes, and fungal pathogens. These multiple interactions play fundamental roles in driving process, structure, and functioning of ecosystems. In this study, we conducted a meta-analysis with 144 papers to investigate the interactions between AMF and plant biotic stressors and their effects on plant growth performance. We found that AMF enhanced plant tolerance to herbivores, nematodes, and fungal pathogens. We also found reciprocal inhibition between AMF and nematodes as well as fungal pathogens, but unidirectional inhibition for AMF on herbivores. Negative effects of AMF on biotic stressors of plants depended on herbivore feeding sites and actioning modes of fungal pathogens. More performance was reduced in root-feeding than in shoot-feeding herbivores and in rotting- than in wilt-fungal pathogens. However, no difference was found for AMF negative effects between migratory and sedentary nematodes. In return, nematodes and fungal pathogens generated more reduction of root colonization in Non-Glomeraceae than in Glomeraceae. Our results suggested that AMF positive effects on plants might be indirectly mediated by competitive inhibition with biotic stressors of plants. These positive and negative interactions make potential contributions to maintaining ecosystem stability and functioning.
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Chiral Lewis Acid Catalyzed Asymmetric Cycloadditions of Disubstituted Ketenes for the Synthesis of ?-Lactones and ?-Lactones.
Org. Lett.
PUBLISHED: 12-04-2013
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Highly diastereo- and enantioselective [2 + 2]- and [4 + 2]-cycloadditions of disubstituted ketenes were realized by chiral Lewis acid catalysis. A series of arylalkylketenes underwent the reaction smoothly with isatins and ?,?-unsaturated ?-ketoesters, providing optically active ?-lactones and ?-lactones with vicinal chiral centers in excellent yields (up to 99%) and enantioselectivities (up to 99% ee), as well as exclusively high diastereoselectivities under 0.2-2 mol % catalyst loading.
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Gold catalyzed nickel disilicide formation: a new solid-liquid-solid phase growth mechanism.
Nano Lett.
PUBLISHED: 12-02-2013
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The vapor-liquid-solid (VLS) mechanism is the predominate growth mechanism for semiconductor nanowires (NWs). We report here a new solid-liquid-solid (SLS) growth mechanism of a silicide phase in Si NWs using in situ transmission electron microcopy (TEM). The new SLS mechanism is analogous to the VLS one in relying on a liquid-mediating growth seed, but it is fundamentally different in terms of nucleation and mass transport. In SLS growth of Ni disilicide, the Ni atoms are supplied from remote Ni particles by interstitial diffusion through a Si NW to the pre-existing Au-Si liquid alloy drop at the tip of the NW. Upon supersaturation of both Ni and Si in Au, an octahedral nucleus of Ni disilicide (NiSi2) forms at the center of the Au liquid alloy, which thereafter sweeps through the Si NW and transforms Si into NiSi2. The dissolution of Si by the Au alloy liquid mediating layer proceeds with contact angle oscillation at the triple point where Si, oxide of Si, and the Au alloy meet, whereas NiSi2 is grown from the liquid mediating layer in an atomic stepwise manner. By using in situ quenching experiments, we are able to measure the solubility of Ni and Si in the Au-Ni-Si ternary alloy. The Au-catalyzed mechanism can lower the formation temperature of NiSi2 by 100 °C compared with an all solid state reaction.
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Enantioselective Friedel-Crafts alkylation for synthesis of 2-substituted indole derivatives.
Chem. Commun. (Camb.)
PUBLISHED: 10-26-2013
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An efficient catalytic asymmetric intermolecular C2 Friedel-Crafts alkylation reaction between N-methyl skatole and ?,?-unsaturated ?-ketoesters has been realized by a chiral N,N-dioxide-Ni(II) complex. The corresponding indole derivatives were obtained in good yield (up to 96%) with excellent enantioselectivities (up to 99% ee) under mild reaction conditions.
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Fluorescent sensor based on BINOL for recognition of cysteine, homocysteine, and glutathione.
J. Org. Chem.
PUBLISHED: 10-25-2013
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A new and simple fluorescent sensor based on unmodified BINOL was developed. The fluorescence of BINOL could be turned off with high selectivity toward Cu(II) among 27 metal ions. Meanwhile, it was found that BINOL was oxidized to dibenzo[a,kl]xanthen-1-ol (A) by Cu(NO3)2. A new peak appeared at ~482 nm upon addition of thiol-containing cysteine (Cys), homocysteine (Hcy), and glutathione (GSH). Thus, a cascade recognition of Cu(II) and Cys, Hcy, and GSH are well presented.
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Farnesoid X receptor up-regulates expression of Lipid transfer inhibitor protein in liver cells and mice.
Biochem. Biophys. Res. Commun.
PUBLISHED: 10-18-2013
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Apolipoprotein F is a component protein mainly secreted by liver and resides on several lipoprotein classes. It can inhibit lipids transfer between different lipoproteins. FXR is a member of the nuclear receptor superfamily which is also highly expressed in the liver. It modulates bile acids synthesis and lipids metabolism by transcriptional regulation. We aimed to determine whether apoF can be regulated by FXR. The FXR agonist Chenodeoxycholic acid (CDCA) and GW4064 both can activate the expression of apoF in liver cell lines and in C57/BL6 mouse liver. This is dependent on the binding of FXR to the FXR element ER1 (-2904 to -2892bp) in the apoF gene promoter. Taken together, we have identified apoF as likely another target gene of FXR.
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Cerebral blood flow changes during rat cardiopulmonary bypass and deep hypothermic circulatory arrest model: A preliminary study.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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Cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA) are important techniques often used in complex cardiac surgery for neonates and infants heart diseases. Cerebral blood flow (CBF) serves as an important physiological parameter and provides valuable hemodynamic information during the surgery. Laser speckle imaging (LSI), as an optical imaging technique, can provide full-field CBF information with a high spatiotemporal resolution. In this preliminary study, we acquired the real-time CBF images with a self-developed miniaturized head-mounted LSI system during the whole CPBillHCA rat model. Relative CBF velocity in veins and arteries in bilateral hemispheres dropped significantly during cooling period and reached to nearly zero during arrest period (n = 5). More interestingly, two rats showing more dramatic CBF variations in veins than in arteries during cooling period exhibited severe cerebral edema after surgery. The real-time full-field CBF imaging during the CPBillHCA surgery could add more insights into the operation and be utilized to study the surgical protocols with the ultimate goal ofreducing neurologic injury after surgery.
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Nano-Structured Gelatin/Bioactive Glass Hybrid Scaffolds for the Enhancement of Odontogenic Differentiation of Human Dental Pulp Stem Cells.
J Mater Chem B Mater Biol Med
PUBLISHED: 10-08-2013
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Tooth decay is one of the most common chronic disorders throughout the world. Regenerating decayed dentin/pulp structure requires the design of novel scaffolding materials that mimic the architecture of natural dental extracellular matrix (ECM) and provide suitable environments for the attachment, proliferation, differentiation, and biomineralization of dental pulp stem cells (DPSCs). In this work, we developed an approach to prepare three-dimensional (3D) nano-fibrous gelatin/silica bioactive glass (NF-gelatin/SBG) hybrid scaffolds that mimic the nano-structured architecture and chemical composition of natural dental ECM. This approach involved the combination of a thermally induced phase separation, sol-gel, and porogen leaching process, and synthesized hybrid scaffolds possessing natural ECM-like architecture, high porosity, well-defined pore size and interconnectivity, and improved mechanical strength. An in vitro cell culture study showed that human DPSCs had a significantly higher proliferation rate on NF-gelatin/SBG scaffolds compared to NF-gelatin scaffolds under the same conditions. Furthermore, the integration of SBG into the hybrid scaffold significantly promoted the differentiation and biomineralization of the human DPSCs. The alkaline phosphatase (ALP) activity and expressions of marker genes for odontogenic differentiation (Col I, ALP, OCN, DSPP and DMP-1) were all significantly higher in the NF-gelatin/SBG than in the NF-gelatin group. Those results were further confirmed by hematoxylin and eosin (H&E) and von Kossa staining, as evidenced by greater ECM secretion and mineral deposition in the hybrid scaffold. In summary, the biomimetic NF-gelatin/SBG hybrid scaffolds provide an excellent environment for the growth and differentiation of human DPSCs and are promising candidates for dentin/pulp tissue regeneration.
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Molecular cloning and functional analysis of the Populus deltoides remorin gene PdREM.
Tree Physiol.
PUBLISHED: 09-26-2013
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Remorins play vital roles in signal transduction, energy transformation, ion flow and transport in plants. Upregulation of remorins correlates with dehiscence and cell maturation; however, no studies have been performed to elucidate the function of remorins in tree species. In this study, a Populus deltoides (Marsh.) plasma membrane-binding protein remorin gene (PdREM) was cloned and characterized by investigating its expression pattern and creating transgenic hybrid poplar (P. davidiana Dode × P. bolleana Lauche) lines expressing sense or antisense PdREM. PdREM was specifically expressed in leaf buds, and immature and mature phloem in P. deltoides. Downregulation of PdREM increased plant height, stem diameter, number of leaves, size of the xylem and phloem zones and induced expression of cell wall biosynthesis- and microfibril angle (MFA)-related genes. Overexpression of PdREM retarded vegetative growth. PdREM may negatively regulate vascular growth by inhibiting secondary cell wall expansion in poplar. In addition, antisense PdREM transgenic poplar had a lower MFA, suggesting that PdREM might contribute to sheet strength and wood properties in poplar. This study sheds light on the molecular mechanism of PdREM in P. deltoides growth and development, and lays the foundation for future functional genomics research into wood formation and the genetic engineering of forest trees with improved wood quality traits.
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Structure and performance of dielectric films based on self-assembled nanocrystals with a high dielectric constant.
Nanotechnology
PUBLISHED: 09-24-2013
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Self-assembled films built from nanoparticles with a high dielectric constant are attractive as a foundation for new dielectric media with increased efficiency and range of operation, due to the ability to exploit nanofabrication techniques and emergent electrical properties originating from the nanoscale. However, because the building block is a discrete one-dimensional unit, it becomes a challenge to capture potential enhancements in dielectric performance in two or three dimensions, frequently due to surface effects or the presence of discontinuities. This is a recurring theme in nanoparticle film technology when applied to the realm of thin film semiconductor and device electronics. We present the use of chemically synthesized (Ba,Sr)TiO3 nanocrystals, and a novel deposition-polymerization technique, as a means to fabricate the dielectric layer. The effective dielectric constant of the film is tunable according to nanoparticle size, and effective film dielectric constants of up to 34 are enabled. Wide area and multilayer dielectrics of up to 8 cm(2) and 190 nF are reported, for which the building block is an 8 nm nanocrystal. We describe models for assessing dielectric performance, and distinct methods for improving the dielectric constant of a nanocrystal thin film. The approach relies on evaporatively driven assembly of perovskite nanocrystals with uniform size distributions in a tunable 7-30 nm size range, coupled with the use of low molecular weight monomer/polymer precursor chemistry that can infiltrate the porous nanocrystal thin film network post assembly. The intercrystal void space (low k dielectric volume fraction) is minimized, while simultaneously promoting intercrystal connectivity and maximizing volume fraction of the high k dielectric component. Furfuryl alcohol, which has good affinity to the surface of (Ba,Sr)TiO3 nanocrystals and miscibility with a range of solvents, is demonstrated to be ideal for the production of nanocomposites. The nanocrystal/furfuryl alcohol dispersions are suitable for the fabrication of thin films by chemical deposition techniques, including spin-coating, printing or a spraying process. To demonstrate the application of this technique to device fabrication, a multilayer capacitor with capacitance of 0.83 nF mm(-2) at 1 MHz is presented.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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