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Find video protocols related to scientific articles indexed in Pubmed.
A FeCl2-graphite sandwich composite with Cl doping in graphite layers: a new anode material for high-performance Li-ion batteries.
Nanoscale
PUBLISHED: 10-23-2014
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A composite with FeCl2 nanocrystals sandwiched between Cl-doped graphite layers has been created via a space-confined nanoreactor strategy. This composite can be used as a new type of anode material for Li-ion batteries, which exhibit high reversible capacity and superior rate capability with excellent cycle life.
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A deeper understanding of the association between CTLA4 +49A/G and acute rejection in renal transplantation: an updated meta-analysis.
Ren Fail
PUBLISHED: 10-10-2014
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Abstract To reevaluate the association between the costimulatory molecule cytotoxic T lymphocyte-associated antigen4 (CTLA4) single nucleotide polymorphism (SNP) +49A/G and acute rejection (AR) in renal transplantation, nine studies published before June 2013 were analyzed. Meta-analysis and cumulative meta-analysis (metacum) were performed for each genotype in a random/fixed effect model. The combined odds ratios (OR) with 95% confidence intervals (CI) were calculated to estimate the strength of the association. In the sensitivity analysis, a single study involved in the meta-analysis was deleted each time to investigate the influence of the individual data sets on the pooled ORs. Meta-analysis regression was used for some influence factors, such as year of publication, total number in each group (AR group and control group), ethnicity, the ratio of GG to GA?+?AA, the ratio of G to A in CTLA4 +49A/G. Overall, a significant correlation was noted between the CTLA4 SNP (+49A/G) and the risk of AR (for GG vs. AG?+?AA: OR?=?1.35, 95% CI?=?1.05-1.73, p?=?0.02; for G vs. A: OR?=?1.21, 95% CI?=?1.03-1.42, p?=?0.02), especially in the Asian subgroup (for GG vs. AG?+?AA: OR?=?1.79, 95% CI?=?1.15-2.78, p?=?0.009; for G vs. A: OR?=?1.47, 95% CI?=?1.04-2.07, p?=?0.03). Of the influence factors, the ratio of GG to GA+AA (p?=?0.046) and the ratio of G to A (p?=?0.017) were significant factors. In conclusion, our results suggest that CTLA4 +49A/G contribute to the risk of AR following renal transplantation.
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Large and fast single-crystal resistive humidity sensitivity of metal pnictide halides containing van der Waals host-guest interactions.
Chem Asian J
PUBLISHED: 08-08-2014
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Two new metal pnictide halides, (Hg(9.75)As(5.5))(GaCl4)3 and (Hg13Sb8)(ZnBr4)4, have been prepared by solid-state reactions. Their structures feature 3D cationic host frameworks built of mercury pnictide polyhedra and form 1D tunnels filled with discrete guest halide polyanions; the guests and hosts are assembled by van der Waals interactions. Both complexes exhibit good single-crystal humidity sensitivity, with a humidity sensitivity factor as big as three orders of magnitude, a quick resistance response, fast recovery, and good reproducibility. This study provide a new way to design promising resistive humidity detectors by introducing van der Waals host-guest interactions into their structures.
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Electron-transfer photochromism to switch bulk second-order nonlinear optical properties with high contrast.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 06-29-2014
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The first bulk electron-transfer photochromic compound with intrinsic second-order nonlinear optical (NLO) photoswitching properties has been synthesized. This system employs an electron-transfer photoactive asymmetric viologen ligand coordinated to a zinc(II) center.
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Establishment of rat model of central venous catheter (CVC): associated infection and evaluation of the virulence of bacterial biofilms.
Cell Biochem. Biophys.
PUBLISHED: 06-29-2014
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In this study, a central venous catheter (CVC)-associated infection model was established in rats to investigate and evaluate the effect of biofilms on the virulence of the pathogens. Twenty-four adult SD rats were randomly divided into biofilm positive (BF+) and biofilm negative (BF-) groups to be challenged with strains of S.epidermidis. Serum levels of inflammatory cytokines were measured and the infection rate and counts of bacteria cells were studied. Compared to rats of BF- group, the serum level of TNF and IL-6 significantly increased in rats of BF+ group (P < 0.01) and the level of IL-10 and IFN-? significantly decreased (P < 0.01), striking the balance of pro-inflammatory/anti-inflammatory cytokines. The infection rate and bacterial counts in tissues and blood of rats of BF + group were significantly higher than those of rats of BF- group (P < 0.05).Inflammatory cell infiltration in vital organs (heart, lung, liver and kidneys) was more significant in rats of BF+ group than that of rats of BF- group. CVC-associated infection model can be successfully reproduced in rats by injecting 5 × 10(6) CFU of S.epidermidis. Biofilm formation can significantly enhance the virulence of the bacteria, leading to uncontrolled infection. The serum level of inflammatory cytokines, infection rate and the extent of inflammatory cell infiltration are important markers for evaluating the virulence of biofilm.
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Trait-mediated seed predation, dispersal and survival among frugivore-dispersed plants in a fragmented subtropical forest, Southwest China.
Integr Zool
PUBLISHED: 06-24-2014
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By tracking the fate of individual seeds from 6 frugivore-dispersed plants with contrasting seed traits in a fragmented subtropical forest in Southwest China, we explored how rodent seed predation and hoarding were influenced by seed traits such as seed size, seed coat hardness and seed profitability. Post-dispersal seed fates varied significantly among the 6 seed species and 3 patterns were witnessed: large-seeded species with a hard seed coat (i.e. Choerospoadias axillaries and Diospyros kaki var. silvestris) had more seeds removed, cached and then surviving at caches, and they also had fewer seeds predated but a higher proportion of seeds surviving at the source; medium-sized species with higher profitability and thinner seed coat (i.e. Phoebe zhennan and Padus braohypoda) were first harvested and had the lowest probability of seeds surviving either at the source or at caches due to higher predation before or after removal; and small-seeded species with lower profitability (i.e. Elaeocarpus japonicas and Cornus controversa) had the highest probability of seeds surviving at the source but the lowest probability of seeds surviving at caches due to lower predation at the source and lower hoarding at caches. Our study indicates that patterns of seed predation, dispersal and survival among frugivore-dispersed plants are highly determined by seed traits such as seed size, seed defense and seed profitability due to selective predation and hoarding by seed-eating rodents. Therefore, trait-mediated seed predation, dispersal and survival via seed-eating rodents can largely affect population and community dynamics of frugivore-dispersed plants in fragmented forests.
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Immune and anti-oxidant functions of ethanol extracts of Scutellaria baicalensis Georgi in mice bearing U14 cervical cancers.
Asian Pac. J. Cancer Prev.
PUBLISHED: 06-18-2014
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The objective was to study the effect of Scutellaria baicalensis Georgi ethanol extracts (SBGE) on immune and anti-oxidant function in U14 tumor-bearing mice.
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Effect of population density on reproduction in Microtus fortis under laboratory conditions.
Acta. Biol. Hung.
PUBLISHED: 05-31-2014
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Between December 2011 and March 2012, the reproductive characteristics of Microtus fortis reared in the laboratory at different population densities were assessed. In all, 258 male and female voles were randomly divided into 4 groups and reared at densities of 2, 4, 6, and 8 animals per cage (sex ratio: 1:1). The results showed that the pregnancy rate (?2 = 21.671, df = 3, P < 0.001) and first farrowing interval (F = 12.355, df = 3, P < 0.001) were significantly different among the different population density groups, but the mean litter size (mean ± SD) was not (F = 2.669, df = 3, P > 0.05). In particular, the reproductive index and sex hormone levels showed a significant difference among the different density groups studied.
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Photochromic hybrid containing in situ-generated benzyl viologen and novel trinuclear [Bi3Cl14]5-: improved photoresponsive behavior by the ?···? interactions and size effect of inorganic oligomer.
Inorg Chem
PUBLISHED: 05-20-2014
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Two new member of (V)((2n+2)/2)[Bi(2n)Cl(8n+2)] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV(2+) = N,N'-dibenzyl-4,4'-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer [Bi3Cl14](5-) counterion. The novel in situ-synthesized symmetric viologen cation with aromatic groups on both sides of 4,4'-bipy would provide more opportunities to create ?···? interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported viologen-metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the viologen dication, and the ?···? interaction behaves as not only a powerful factor to stabilize the viologen monocation radical but also the second electron-transfer pathway, from a ?-conjugated substituent to a viologen cation, for the photochromic process.
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Photoswitching CO? capture and release in a photochromic diarylethene metal-organic framework.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 05-07-2014
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We demonstrate herein a promising pathway towards low-energy CO2 capture and release triggered by UV and visible light. A photosensitive diarylethene ligand was used to construct a photochromic diarylethene metal-organic framework (DMOF). A local photochromic reaction originating from the framework movement induced by the photoswitchable diarylethene unit resulted in record CO2-desorption capacity of 75% under static irradiation and 76% under dynamic irradiation.
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Research on testing the nonlinear optical performance of nonlinear optical materials based on the effect of second-harmonic generation.
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 05-03-2014
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In the present paper the authors report a research on testing the nonlinear optical performance of optical materials in visible and infrared band. Based on the second order nonlinear optic principle and the photoelectric signal detection technology, the authors have proposed a new testing scheme in which a infrared OPO laser and a method for separating the beams arising from frequency matching and the light produced by other optical effects were used. The OPO laser is adopted as light source to avoid the error of measurement caused by absorption because the double frequency signal of the material is in the transmittance band Our research work includes testing system composition, operational principle and experimental method. The experimental results of KTP, KDP, AGS tested by this method were presented. In the experiment several new infrared non-linear materials were found. This method possesses the merits of good stability and reliability, high sensitivity, simple operation and good reproducibility, which can effectively make qualitative and semi-quantitative test for optical material's nonlinear optical properties from visible to infrared. This work provides an important test -method for the research on second order nonlinear optical materials in visible, infrared and ultraviolet bands.
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A highly stable 3D acentric zinc metal-organic framework based on two symmetrical flexible ligands: high second-harmonic-generation efficiency and tunable photoluminescence.
Inorg Chem
PUBLISHED: 04-14-2014
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A 3D metal-organic framework (MOF), [Zn(BPHY)(SA)]n (1; BPHY = 1,2-bis(4-pyridyl)hydrazine, H2SA = succinic acid), which crystallizes in a noncentrosysmmetric space group (Cc), has been solvothermally obtained and testified to be a good nonlinear-optical material with the largest second-harmonic-generation response among the known MOFs based on sysmmetric ligands and high stability. Ultraviolet-to-visible tunable emission for 1 is observed.
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In situ observation on the dynamic process of evaporation and crystallization of sodium nitrate droplets on a ZnSe substrate by FTIR-ATR.
J Phys Chem A
PUBLISHED: 04-02-2014
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Sodium nitrate is a main component of aging sea salt aerosol, and its phase behavior has been studied repeatedly with wide ranges observed in the efflorescence relative humidity (RH) in particular. Studies of the efflorescence dynamics of NaNO3 droplets deposited on a ZnSe substrate are reported, using an in situ Fourier transform infrared attenuated total reflection (FTIR-ATR) technique. The time-dependence of the infrared spectra of NaNO3 aerosols accompanying step changes in RH have been measured with high signal-to-noise ratio. From the IR difference spectra recorded, changes of the time-dependent absorption peak area of the O-H stretching band (?-OH, ?3400 cm(-1)) and the nitrate out-of-plane bending band (?2-NO3(-), ?836 cm(-1)) are obtained. From these measurements, changes in the IR signatures can be attributed to crystalline and solution phase nitrate ions, allowing the volume fraction of the solution droplets that have crystallized to be determined. Then, using these clear signatures of the volume fraction of droplets that have yet to crystallize, the homogeneous and heterogeneous nucleation kinetics can be studied from conventional measurements using a steady decline in RH. The nucleation rate measurements confirm that the rate of crystallization in sodium nitrate droplets is considerably less than in ammonium sulfate droplets at any particular degree of solute supersaturation, explaining the wide range of efflorescence RHs observed for sodium nitrate in previous studies. We demonstrate that studying nucleation kinetics using the FTIR-ATR approach has many advantages over brightfield imaging studies on smaller numbers of larger droplets or measurements made on single levitated particles.
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Graphene-cyclodextrin-cytochrome c layered assembly with improved electron transfer rate and high supramolecular recognition capability.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 03-01-2014
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This study aimed to develop a new graphene-based layered assembly, named graphene-cyclodextrin-cytochrome c with improved electron transfer rate. This assembly has combined high conductivity of graphene nanosheets (GNs), selectively binding properties and electronegativity of cyclodextrins (CDs), as well as electropositivity of cytochrome c (Cyt c). This assembly can also mimic the confined environments of the intermembrane space of mitochondria. A ?-cyclodextrin (?-CD) functionalized GN (GN-CD) assembly was initially prepared by a simple wet-chemical strategy, i.e., in situ thermal reduction of graphene oxide with hydrazine hydrate in the presence of ?-CD. Cyt c was then intercalated to the GN-CD assembly to form a layered self-assembled structure, GN-CD-Cyt c, through electrostatic interaction. Compared with GNs and GN-CD, GN-CD-Cyt c assembly displayed improved electron transfer rate and high supramolecular recognition capability toward six probe molecules.
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Role of c-Src activity in the regulation of gastric cancer cell migration.
Oncol. Rep.
PUBLISHED: 02-02-2014
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Gastric cancer is associated with increased migration and invasion. In the present study, we explored the role of c-Src in gastric cancer cell migration and invasion. BGC-823 gastric cancer cells were used to investigate migration following treatment of these cells with the c-Src inhibitors, PP2 and SU6656. Migration and invasion were analyzed by wound healing and Transwell assays. Western blot analysis was used to detect the expression of MT1-MMP and VEGF-C, while the activity of MMP2 and MMP9 was monitored with gelatin zymography assay. Immunoprecipitation was used to detect interactions among furin, pro-MT1-MMP and pro-VEGF-C. MT1-MMP and VEGF-C expression levels were inhibited by PP2 and SU6656 treatment, in accordance with decreased c-Src activity. Similarly, the zymography assay demonstrated that the activity of MMP2 and MMP9 was decreased following PP2 or SU6656 treatment. Blockade of c-Src also inhibited the invasive and migratory capacity of BGC-823 cells. Notably, c-Src interacted with furin in vivo, while interactions between furin and its substrates, pro-MT1-MMP and pro-VEGF-C, were decreased by c-Src inhibitors. In conclusion, the interaction among furin and pro-MT1-MMP or pro-VEGF-C or other tumor-associated precursor enzymes can be regulated by c-Src activity, thus reducing or changing the expression of these enzymes in order to reduce the development of gastric cancer, invasion and metastasis.
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Triphenylalanine peptides self-assemble into nanospheres and nanorods that are different from the nanovesicles and nanotubes formed by diphenylalanine peptides.
Nanoscale
PUBLISHED: 01-27-2014
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Understanding the nature of the self-assembly of peptide nanostructures at the molecular level is critical for rational design of functional bio-nanomaterials. Recent experimental studies have shown that triphenylalanine(FFF)-based peptides can self-assemble into solid plate-like nanostructures and nanospheres, which are different from the hollow nanovesicles and nanotubes formed by diphenylalanine(FF)-based peptides. In spite of extensive studies, the assembly mechanism and the molecular basis for the structural differences between FFF and FF nanostructures remain poorly understood. In this work, we first investigate the assembly process and the structural features of FFF nanostructures using coarse-grained molecular dynamics simulations, and then compare them with FF nanostructures. We find that FFF peptides spontaneously assemble into solid nanometer-sized nanospheres and nanorods with substantial ?-sheet contents, consistent with the structural properties of hundred-nanometer-sized FFF nano-plates characterized by FT-IR spectroscopy. Distinct from the formation mechanism of water-filled FF nanovesicles and nanotubes reported in our previous study, intermediate bilayers are not observed during the self-assembly process of FFF nanospheres and nanorods. The peptides in FFF nanostructures are predominantly anti-parallel-aligned, which can form larger sizes of ?-sheet-like structures than the FF counterparts. In contrast, FF peptides exhibit lipid-like assembly behavior and assemble into bilayered nanostructures. Furthermore, although the self-assembly of FF and FFF peptides is mostly driven by side chain-side chain (SC-SC) aromatic stacking interactions, the main chain-main chain (MC-MC) interactions also play an important role in the formation of fine structures of the assemblies. The delicate interplay between MC-MC and SC-SC interactions results in the different nanostructures formed by the two peptides. These findings provide new insights into the structure and self-assembly pathway of di-/tri-phenylalanine peptide assemblies, which might be helpful for the design of bioinspired nanostructures.
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The complete mitochondrial genome of the Hynobius maoershanensis (Caudata: hynobiidae).
Mitochondrial DNA
PUBLISHED: 01-24-2014
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Abstract The Hynobius maoershanensis is a member of hynobiidae, endemic to Mountain Maoer in Guangxi province, China. It was first found and reported in 2006 and so far there is a little molecular research about it. The complete mitochondrial genome of H. maoershanensis has been obtained for the first time in this study. The circular genome (16,412?bp in length) consisted of 37 typical animal mitochondrial genes (13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes) and 1 control region. Overall base composition of the complete mitochondrial DNA was 33% A, 32% T, 21% C, and 14% G with AT (65%).
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Novel thioarsenates {[Mn(2,2'-bipy)2(SCN)][Mn(2,2'-bipy)](As(V)S4)}2 and {[Mn(2,2'-bipy)2(SCN)]2[As(III)2(S2)2S2]}: introducing an anionic second ligand to modify MnII complex cations of 2,2'-bipyridine.
Dalton Trans
PUBLISHED: 01-21-2014
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Two novel manganese thioarsenates, {[Mn(2,2'-bipy)2(SCN)][Mn(2,2'-bipy)](As(V)S4)}2 (1, 2,2'-bipy = 2,2'-bipyridine) and {[Mn(2,2'-bipy)2(SCN)]2[As(III)2(S2)2S2]} (2), containing thiocyanate-modified Mn-2,2'-bipy complex cations were synthesized. They feature two terminal [Mn(2,2'-bipy)2(SCN)](+) complex cations bridged by a polyanion {[Mn(2,2'-bipy)]2(As(V)S4)2}(2-) for 1 and a cyclic thioarsenate anion (As(III)2S6)(2-) for 2. In 2, the [As(III)2(S2)2S2](2-) anion can be described as two (As(III)S3)(3-) trigonal-pyramids interlinked through S-S bonds. The method to obtain new metal complex cations shown here, introducing an anionic second ligand to modify the number of coordination sites and the charges of the metal complex cations simultaneously, is different from the traditional methods, varying either the TM center or the organic ligand or employing mixed neutral organic ligands, and may open up a new route for preparing novel chalcogenidometalates. Compounds 1 and 2 exhibit wide optical gaps of 2.20 and 2.67 eV, respectively, and photoluminescence with the emission maxima occurring around 440 nm. Magnetic measurements show the presence of antiferromagnetic interactions between Mn(II) centers in the two compounds.
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Protein tyrosine phosphatase ? targets apical junction complex proteins in the intestine and regulates epithelial permeability.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-02-2014
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Protein tyrosine phosphatase (PTP)? (PTPRS) was shown previously to be associated with susceptibility to inflammatory bowel disease (IBD). PTP?(-/-) mice exhibit an IBD-like phenotype in the intestine and show increased susceptibility to acute models of murine colitis. However, the function of PTP? in the intestine is uncharacterized. Here, we show an intestinal epithelial barrier defect in the PTP?(-/-) mouse, demonstrated by a decrease in transepithelial resistance and a leaky intestinal epithelium that was determined by in vivo tracer analysis. Increased tyrosine phosphorylation was observed at the plasma membrane of epithelial cells lining the crypts of the small bowel and colon of the PTP?(-/-) mouse, suggesting the presence of PTP? substrates in these regions. Using mass spectrometry, we identified several putative PTP? intestinal substrates that were hyper-tyrosine-phosphorylated in the PTP?(-/-) mice relative to wild type. Among these were proteins that form or regulate the apical junction complex, including ezrin. We show that ezrin binds to and is dephosphorylated by PTP? in vitro, suggesting it is a direct PTP? substrate, and identified ezrin-Y353/Y145 as important sites targeted by PTP?. Moreover, subcellular localization of the ezrin phosphomimetic Y353E or Y145 mutants were disrupted in colonic Caco-2 cells, similar to ezrin mislocalization in the colon of PTP?(-/-) mice following induction of colitis. Our results suggest that PTP? is a positive regulator of intestinal epithelial barrier, which mediates its effects by modulating epithelial cell adhesion through targeting of apical junction complex-associated proteins (including ezrin), a process impaired in IBD.
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Design and Syntheses of Electron-Transfer Photochromic Metal-Organic Complexes Using Nonphotochromic Ligands: A Model Compound and the Roles of Its Ligands.
Inorg Chem
PUBLISHED: 12-23-2013
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The model compound [Zn(HCOO)2(4,4-bipy)] (1; 4,4-bipy = 4,4-bipyridine) is selected in this work to demonstrate the effectiveness of our previously proposed design strategy for electron-transfer photochromic metal-organic complexes. The electron-transfer photochromic behavior of 1 has been discovered for the first time. Experimental and theoretical data illustrate that the photochromism of 1 can be attributed to the electron transfer from formato to 4,4-bipy and the formation of a radical photoproduct. The electron transfer prefers to occur between formato and 4,4-bipy, which are combined directly by the Zn(II) atoms. A high-contrast (up to 8.3 times) photoluminescence switch occurs during the photochromic process. The similarity of photochromic behaviors among 1 and its analogues as well as viologen compounds has also been found. Photochromic studies of this model compound indicate that new electron-transfer photochromic metal-organic complexes can be largely designed and synthesized by the rational assembly of nonphotochromic electron-donating and electron-accepting ligands.
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Manipulating the concavity of rhodium nanocubes enclosed by high-index facets via site-selective etching.
Chem. Commun. (Camb.)
PUBLISHED: 12-13-2013
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Manipulating the degrees of concavity or Miller indices of high-index facets is significant for metal nanocrystals to further tailor their properties; however, generating a concave surface with negative curvature is still in the early development stage and tuning the degree of concavity remains a challenge. Herein, we have developed a simple and effective site-selective etching strategy to manipulate the concavity of rhodium (Rh) nanocrystals with high-index facets.
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Plasma adrenomedullin levels are associated with long-term outcomes of acute ischemic stroke.
Peptides
PUBLISHED: 11-14-2013
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Plasma adrenomedullin concentration has been found to be enhanced in ischemic stroke. Up to now, little is known about the association of plasma adrenomedullin concentration with clinical outcomes of ischemic stroke. This study recruited 138 patients with ischemic stroke and 138 healthy volunteers. Unfavorable outcome was defined as modified Rankin Scale score >2 at 3 months. Plasma adrenomedullin concentrations were determined by enzyme-linked immunosorbent assay. Plasma adrenomedullin concentrations were statistically significantly higher in patients than in healthy individuals (79.9±27.3pg/mL vs. 36.8±10.4pg/mL; P<0.001). 3-Month mortality was 20.3% (28/138) and sixty-six patients (47.8%) had unfavorable outcome in 3 months. A logistic regression analysis identified plasma adrenomedullin concentration as an independent predictor of 3-month mortality (odds ratio, 1.211; 95% confidence interval, 1.101-1.582; P=0.004) and unfavorable outcome (odds ratio, 1.193; 95% confidence interval, 1.082-1.447; P=0.006). Receiver operating characteristic curve analysis showed that plasma adrenomedullin concentration predicted 3-month mortality (area under curve, 0.806; 95% confidence interval, 0.730-0.868) and unfavorable outcome (area under curve, 0.816; 95% confidence interval, 0.742-0.877) with the high predictive value. Its predictive performance was similar to that of National Institutes of Health Stroke Scale score (P=0.694 or 0.206). Its combined use with National Institutes of Health Stroke Scale score did not improve the predictive value (P=0.236 or 0.590). Thus, adrenomedullin may aid to predict long-term clinical outcomes of patients with ischemic stroke.
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Dimension projection matrix/tree: interactive subspace visual exploration and analysis of high dimensional data.
IEEE Trans Vis Comput Graph
PUBLISHED: 09-21-2013
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For high-dimensional data, this work proposes two novel visual exploration methods to gain insights into the data aspect and the dimension aspect of the data. The first is a Dimension Projection Matrix, as an extension of a scatterplot matrix. In the matrix, each row or column represents a group of dimensions, and each cell shows a dimension projection (such as MDS) of the data with the corresponding dimensions. The second is a Dimension Projection Tree, where every node is either a dimension projection plot or a Dimension Projection Matrix. Nodes are connected with links and each child node in the tree covers a subset of the parent nodes dimensions or a subset of the parent nodes data items. While the tree nodes visualize the subspaces of dimensions or subsets of the data items under exploration, the matrix nodes enable cross-comparison between different combinations of subspaces. Both Dimension Projection Matrix and Dimension Project Tree can be constructed algorithmically through automation, or manually through user interaction. Our implementation enables interactions such as drilling down to explore different levels of the data, merging or splitting the subspaces to adjust the matrix, and applying brushing to select data clusters. Our method enables simultaneously exploring data correlation and dimension correlation for data with high dimensions.
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New mercury-contained cationic frameworks stabilized by (GaCl4)- unit via weak electrostatic forces in supramolecular compounds (Hg11P4)(GaCl4)4 and (Hg3AsS)(GaCl4).
Dalton Trans
PUBLISHED: 09-12-2013
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Two new inorganic supramolecular compounds, (Hg11P4)(GaCl4)4 (1) and (Hg3AsS)(GaCl4) (2), have been prepared by the solid-state reactions. Their structures are characterized by mercury-containing cationic hosts and discrete (GaCl4)(-) guests, which is a derivative of a very strong Lewis acid. The three-dimensional cationic framework of 1, (Hg11P4)(4+), is marvellously extended by Hg2(2+) and Hg3(2+) groups as well as Hg(2+) ions to form two large tunnels with different sizes each embedded with two columns of (GaCl4)(-) anions. Compound 2 features a layered structure with (GaCl4)(-) tetrahedra being intercalated between two-dimensional (Hg3AsS)(+) layers and it is the first mercury pnictidechalcohalide. It is found that the weak electrostatic forces between hosts and guests play a key role in the stabilization of the whole structures of 1 and 2, which is strikingly different from almost all the reported metal pnictidehalide and chalcohalide supramolecular compounds. Optical dielectric constants calculations show that both 1 and 2 possess strong dielectric anisotropy.
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IL-10R polymorphisms are associated with very-early-onset ulcerative colitis.
Inflamm. Bowel Dis.
PUBLISHED: 08-22-2013
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Interleukin-10 (IL-10) signaling genes are attractive inflammatory bowel disease (IBD) candidate genes as IL-10 restricts intestinal inflammation, IL-10 polymorphisms have been associated with IBD in genome-wide association studies, and mutations in IL-10 and IL-10 receptor (IL-10R) genes have been reported in immunodeficient children with severe infantile-onset IBD. Our objective was to determine if IL-10R polymorphisms were associated with early-onset IBD (EO-IBD) and very-early-onset IBD (VEO-IBD).
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Ferric chloride-Graphite Intercalation Compounds as Anode Materials for Li-ion Batteries.
ChemSusChem
PUBLISHED: 08-16-2013
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Ferric chloride-graphite intercalation compounds (FeCl3 -GICs) with stage?1 and stage?2 structures were synthesized by reacting FeCl3 and expanded graphite (EG) in air in a stainless-steel autoclave. As rechargeable Li-ion batteries, these FeCl3 -GICs exhibit high capacity, excellent cycling stability, and superior rate capability, which could be attributed to their unique intercalation features. This work may enable new possibilities for the fabrication of Li-ion batteries.
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Ln3GaS6 (Ln = Dy, Y): new infrared nonlinear optical materials with high laser induced damage thresholds.
Dalton Trans
PUBLISHED: 08-16-2013
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Two new ternary rare earth chalcogenides, Dy3GaS6 (1) and Y3GaS6 (2), are reported here. They both crystallize in the orthorhombic space group Cmc21 (no. 36). Both are synthesized in pure phase and show phase-matchable second harmonic generation (SHG) of about 0.2 and 0.5 times, respectively for 1 and 2, as strong as that of KTiOPO4 (KTP) based on the powder SHG measurement at the wavelength of 1910 nm. They possess high powder laser induced damage thresholds (LIDTs), respectively, about 14 and 18 times that of AgGaS2 (AGS) based on the powder LIDT measurements under 1064 nm laser irradiation. They both exhibit wide transparency in the IR region (2.5–25 ?m). It is believed that the title compounds are new candidates for nonlinear optical (NLO) materials in the IR region. To gain further insights into the NLO and LIDT properties of 1 and 2, the calculations of second-order NLO susceptibility and lattice energy density (LED) were also performed to explain their SHG efficiencies and high LIDTs.
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Homochiral zinc(II) coordination compounds based on in-situ-generated chiral amino acid-tetrazole ligands: circular dichroism, excitation light-induced tunable photoluminescence, and energetic performance.
Inorg Chem
PUBLISHED: 08-12-2013
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We employed two pairs of new in-situ-generated chiral amino acid-tetrazole ligands in constructing homochiral Zn(II) coordination compounds: [Zn(tzet)]n (1a for (S)-tzet and 1b for (R)-tzet, H2tzet = N-[2-(1H-tetrazol-5-yl)ethyl]tryptophan) and [Zn(tzep)(H2O)2]·H2O (2a for (S)-tzep and 2b for (R)-tzep, H2tzep = N-[2-(1H-tetrazol-5-yl)ethyl]proline), which were hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Structural analysis reveals that 1 features a 2D homochiral framework generated by both tetrazolate and carboxylate bridges in tzet(2-) ligands. The isolated structure of 2 is stabilized by extensive hydrogen bonds, which leads to formation of a supramolecular 2D architecture. The absolute configuration induced at the nitrogen atoms of 1 and 2 is strictly related to the neighboring chiral carbon atoms by hydrogen-bond interactions. To further investigate their chirality, the combined experimental and theoretical analyses of circular dichroism spectra reveal the absolute configurations and nature of the Cotton effects. Solid-state excitation and emission spectra for 1 and 2 at room temperature were investigated with relevant density of states calculation, and tunable photoluminescence emission of 1 under different excitation wavelengths was discussed. As nitrogen-rich tetrazolate compounds, 1 and 2 possess higher enthalpies of combustion and may serve as a new family of promising energetic materials.
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Ferroelectric Transition in the Inorganic Supramolecular Complex (Hg6 P4 )(CuCl3 )2.
Chem Asian J
PUBLISHED: 08-04-2013
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In a state of disorder: An inorganic supramolecular complex, (Hg6 P4 )(CuCl3 )2 , was prepared that undergoes a ferroelectric transition at about 37?K, and its spontaneous polarization was determined to be about 114??C?m(-2) in the polycrystalline form using the high-precision pyroelectric current method. Weak electrostatic supramolecular interactions in 1 lead to the dynamic disorder of ions and ferroelectric transition.
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Identification of HKDC1 and BACE2 as genes influencing glycemic traits during pregnancy through genome-wide association studies.
Diabetes
PUBLISHED: 07-31-2013
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Maternal metabolism during pregnancy impacts the developing fetus, affecting offspring birth weight and adiposity. This has important implications for metabolic health later in life (e.g., offspring of mothers with pre-existing or gestational diabetes mellitus have an increased risk of metabolic disorders in childhood). To identify genetic loci associated with measures of maternal metabolism obtained during an oral glucose tolerance test at ?28 weeks gestation, we performed a genome-wide association study of 4,437 pregnant mothers of European (n = 1,367), Thai (n = 1,178), Afro-Caribbean (n = 1,075), and Hispanic (n = 817) ancestry, along with replication of top signals in three additional European ancestry cohorts. In addition to identifying associations with genes previously implicated with measures of glucose metabolism in nonpregnant populations, we identified two novel genome-wide significant associations: 2-h plasma glucose and HKDC1, and fasting C-peptide and BACE2. These results suggest that the genetic architecture underlying glucose metabolism may differ, in part, in pregnancy.
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Moderating effects and maintenance of lung cancer cellular immune functions by CIK cell therapy.
Asian Pac. J. Cancer Prev.
PUBLISHED: 07-27-2013
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To study the CIK cell treatment effects on regulation of cellular immune function disorders in patients with lung cancer, and to analyze the time characteristics.
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Orientation domains in vacancy-ordered titanium monoxide.
Acta Crystallogr B Struct Sci Cryst Eng Mater
PUBLISHED: 07-15-2013
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This paper presents a study on orientation domains in the vacancy-ordered titanium monoxide TiOx. Transmission electron microscopy analysis revealed the co-existence of 12 possible TiOx monoclinic domain variants, which are induced by the cubic-to-monoclinic phase transition attributed to the Ti and O vacancy ordering. These 12 monoclinic domain variants which are predicted by group theory might be randomly arranged. Furthermore, several hours of electron beam irradiation can lead to the vacancy ordering-disordering transition (i.e. monoclinic-to-cubic phase transformation) in TiOx. Our results shed light on the structural characteristics in TiOx nanostructures and thus contribute to the fabrication and design of the related nanostructures.
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Large mid-IR second-order nonlinear-optical effects designed by the supramolecular assembly of different bond types without IR absorption.
Inorg Chem
PUBLISHED: 07-09-2013
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Two new different-bond-type hybrid compounds, (Hg6P4Cl3)(PbCl3) (1) and (Hg23P12)(ZnCl4)6 (2), with supramolecular interactions between host and guest moieties, which based on metal-pnicogen, pnicogen-pnicogen, and metal-halogen bonds were obtained by solid-state reactions. Compounds 1 and 2 show large second-harmonic-generation (SHG) activity and are transparent in the wide mid-IR region, providing an effective route for searching new IR nonlinear-optical material systems by combining two or more different bond types with no IR absorption within a single compound through supramolecular assembly. Theory predications based on first-principles calculations are also performed on the SHG properties of 1 and 2.
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The chromosome 3q25 genomic region is associated with measures of adiposity in newborns in a multi-ethnic genome-wide association study.
Hum. Mol. Genet.
PUBLISHED: 04-10-2013
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Newborns characterized as large and small for gestational age are at risk for increased mortality and morbidity during the first year of life as well as for obesity and dysglycemia as children and adults. The intrauterine environment and fetal genes contribute to the fetal size at birth. To define the genetic architecture underlying the newborn size, we performed a genome-wide association study (GWAS) in 4281 newborns in four ethnic groups from the Hyperglycemia and Adverse Pregnancy Outcome Study. We tested for association with newborn anthropometric traits (birth length, head circumference, birth weight, percent fat mass and sum of skinfolds) and newborn metabolic traits (cord glucose and C-peptide) under three models. Model 1 adjusted for field center, ancestry, neonatal gender, gestational age at delivery, parity, maternal age at oral glucose tolerance test (OGTT); Model 2 adjusted for Model 1 covariates, maternal body mass index (BMI) at OGTT, maternal height at OGTT, maternal mean arterial pressure at OGTT, maternal smoking and drinking; Model 3 adjusted for Model 2 covariates, maternal glucose and C-peptide at OGTT. Strong evidence for association was observed with measures of newborn adiposity (sum of skinfolds model 3 Z-score 7.356, P = 1.90×10?¹³, and to a lesser degree fat mass and birth weight) and a region on Chr3q25.31 mapping between CCNL and LEKR1. These findings were replicated in an independent cohort of 2296 newborns. This region has previously been shown to be associated with birth weight in Europeans. The current study suggests that association of this locus with birth weight is secondary to an effect on fat as opposed to lean body mass.
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An ultra-low Pd loading nanocatalyst with high activity and stability for CO oxidative coupling to dimethyl oxalate.
Chem. Commun. (Camb.)
PUBLISHED: 04-05-2013
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A Pd/?-Al2O3 nanocatalyst with ultra-low Pd loading exhibits high activity and stability for CO oxidative coupling to dimethyl oxalate, which was prepared by a Cu(2+)-assisted in situ reduction method at room temperature. The small size and high dispersion of Pd nanoparticles facilitated by Cu(2+) ions are responsible for the excellent catalytic activity.
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Improved photochromic properties on viologen-based inorganic-organic hybrids by using ?-conjugated substituents as electron donors and stabilizers.
Inorg Chem
PUBLISHED: 01-16-2013
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A series of inorganic-organic hybrid compounds L(2)(Bi(2)Cl(10)) (L = HMV(2+) = N-proton-N-methyl-4,4-bipyridinium for 1, L = HBzV(2+) = N-proton-N-benzyl-4,4-bipyridinium for 2, and L = HPeV(2+) = N-proton-N-phenethyl-4,4-bipyridinium for 3) have been successfully synthesized by an in situ solvothermal reaction. Compounds 1-3, with the same metal halide as anions but different asymmetric viologen molecules as cations, are ideal model compounds for investigating the detailed effect of different photochromically active molecules on the photochromic properties of the hybrids. Compound 1 shows no photochromic behavior, but compounds 2 and 3 possess photochromism and show a faster photoresponse rate than other reported viologen metal halide hybrids. Studies on the relationship between the structure and photochromic behavior clearly reveal that ?-conjugated substituents could be used to improve the photoresponsibility and enrich the developed color efficiently and that the ?···? interaction among organic components may not only be a powerful factor to stabilize the viologen monocation radical but also act as the second path of electron transfer from the ?-conjugated substituent to the viologen cation for the photochromic process, which significantly influences the photochromic properties.
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Novel single-crystals voltage-dependent effect and magnetic order of Ln2ZrQ5 (Ln = La, Sm, Gd; Q = S, Se) semiconductors.
Dalton Trans
PUBLISHED: 01-10-2013
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A series of rare-earth zirconium chalcogenides Ln(2)ZrQ(5) (Ln = La, Sm, Gd; Q = S, Se) synthesized by using boron as the reducing reagent show unprecedented single-crystals intrinsic voltage-dependent effects and order antiferromagnetically.
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Prognostic significance of plasma visfatin levels in patients with ischemic stroke.
Peptides
PUBLISHED: 01-05-2013
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Plasma visfatin concentration has been enhanced in ischemic stroke. The aim of the current investigation was to test whether determination of visfatin in plasma is associated with 6-month clinical outcomes including mortality and unfavorable outcome (modified Rankin Scale score>2) in the patients with ischemic stroke. Between July 2009 and January 2012, plasma visfatin concentrations of 186 patients and 100 healthy individuals were quantified by enzyme-linked immunosorbent assay. Plasma visfatin concentrations were higher in patients than in healthy individuals (108.5±41.1 ng/mL vs. 13.8±3.9 ng/mL, P<0.001). A logistic regression analysis selected plasma visfatin concentration as an independent predictor for 6-month clinical outcomes (both P<0.01). Using receiver operating characteristic curve analysis, plasma visfatin concentration was found to predict 6-month clinical outcomes with the high predictive performance. The predictive value of visfatin was in the range of National Institutes of Health Stroke Scale score (both P>0.05). Combined use of visfatin and National Institutes of Health Stroke Scale score did not improve the predictive significance (both P>0.05). Thus, visfatin may help in the prediction of long-term clinical outcomes in patients with ischemic stroke.
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Isolation and functional analyses of a putative floral homeotic C-function gene in a basal eudicot London plane tree (Platanus acerifolia).
PLoS ONE
PUBLISHED: 01-01-2013
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The identification of mutants in model plant species has led to the isolation of the floral homeotic function genes that play crucial roles in flower organ specification. However, floral homeotic C-function genes are rarely studied in basal eudicots. Here, we report the isolation and characterization of the AGAMOUS (AG) orthologous gene (PaAG) from a basal eudicot London plane tree (Platanus acerifolia Willd). Phylogenetic analysis showed that PaAG belongs to the C- clade AG group of genes. PaAG was found to be expressed predominantly in the later developmental stages of male and female inflorescences. Ectopic expression of PaAG-1 in tobacco (Nicotiana tabacum) resulted in morphological alterations of the outer two flower whorls, as well as some defects in vegetative growth. Scanning electron micrographs (SEMs) confirmed homeotic sepal-to-carpel transformation in the transgenic plants. Protein interaction assays in yeast cells indicated that PaAG could interact directly with PaAP3 (a B-class MADS-box protein in P. acerifolia), and also PaSEP1 and PaSEP3 (E-class MADS-box proteins in P. acerifolia). This study performed the functional analysis of AG orthologous genes outside core eudicots and monocots. Our findings demonstrate a conserved functional role of AG homolog in London plane tree, which also represent a contribution towards understanding the molecular mechanisms of flower development in this monoecious tree species.
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Rac2-deficiency leads to exacerbated and protracted colitis in response to Citrobacter rodentium infection.
PLoS ONE
PUBLISHED: 01-01-2013
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Recent genetic-based studies have implicated a number of immune-related genes in the pathogenesis of inflammatory bowel disease (IBD). Our recent genetic studies showed that RAC2 is associated with human IBD; however, its role in disease pathogenesis is unclear. Given Rac2s importance in various fundamental immune cell processes, we investigated whether a defect in Rac2 may impair host immune responses in the intestine and promote disease in the context of an infection-based (Citrobacter rodentium) model of colitis. In response to infection, Rac2(-/-) mice showed i) worsened clinical symptoms (days 13-18), ii) increased crypt hyperplasia at days 11 and 22 (a time when crypt hyperplasia was largely resolved in wild-type mice; WT), and iii) marked mononuclear cell infiltration characterized by higher numbers of T (CD3(+)) cells (day 22), compared to WT-infected mice. Moreover, splenocytes harvested from infected Rac2(-/-) mice and stimulated in vitro with C. rodentium lysate produced considerably higher levels of interferon-? and interleukin-17A. The augmented responses observed in Rac2(-/-) mice did not appear to stem from Rac2s role in NADPH oxidase-driven reactive oxygen species production as no differences in crypt hyperplasia, nor inflammation, were observed in infected NOX2(-/-) mice compared to WT. Collectively, our findings demonstrate that Rac2(-/-) mice develop more severe disease when subjected to a C. rodentium-induced model of infectious colitis, and suggest that impaired Rac2 function may promote the development of IBD in humans.
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Axonal fiber terminations concentrate on gyri.
Cereb. Cortex
PUBLISHED: 12-20-2011
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Convoluted cortical folding and neuronal wiring are 2 prominent attributes of the mammalian brain. However, the macroscale intrinsic relationship between these 2 general cross-species attributes, as well as the underlying principles that sculpt the architecture of the cerebral cortex, remains unclear. Here, we show that the axonal fibers connected to gyri are significantly denser than those connected to sulci. In human, chimpanzee, and macaque brains, a dominant fraction of axonal fibers were found to be connected to the gyri. This finding has been replicated in a range of mammalian brains via diffusion tensor imaging and high-angular resolution diffusion imaging. These results may have shed some lights on fundamental mechanisms for development and organization of the cerebral cortex, suggesting that axonal pushing is a mechanism of cortical folding.
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Structural diversity, optical and magnetic properties of a series of manganese thioarsenates with 1,10-phenanthroline or 2,2-bipyridine ligands: using monodentate methylamine as an alkalinity regulator.
Inorg Chem
PUBLISHED: 12-08-2011
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The exploration in two hydro(solvo)thermal reaction systems As/S/Mn(2+)/phen/methylamine aqueous solution and As/S/Mn(2+)/2,2-bipy/H(2)O affords five new manganese thioarsenates with diverse structures, namely, (CH(3)NH(3)){[Mn(phen)(2)](As(V)S(4))}·phen (1 and 1), (CH(3)NH(3))(2){[Mn(phen)](2)(As(V)S(4))(2)} (2), {[Mn(phen)(2)](As(III)(2)S(4))}(n) (3), {[Mn(phen)](3)(As(III)S(3))(2)}·H(2)O (4), and {[Mn(2,2-bipy)(2)](2)(As(V)S(4))}[As(III)S(S(5))] (5). Compound 1 comprises a {[Mn(phen)(2)](As(V)S(4))}(-) complex anion, a monoprotonated methylamine cation and a phen molecule. Compound 2 contains a butterfly like {[Mn(phen)](2)(As(V)S(4))(2)}(2-) anion charge compensated by two monoprotonated methylamine cations. Compound 3 is a neutral chain formed by a helical (1)(?)(As(III)S(2)(-)) vierer chain covalently bonds to [Mn(II)(phen)](2+) complexes via all its terminal S atoms. Compound 4 features a neutral chain showing the stabilization of noncondensed (As(III)S(3))(3-) anions in the coordination of [Mn(II)(phen)](2+) complex cations. Compound 5 features a mixed-valent As(III)/As(V) character and an interesting chalcogenidometalates structure, where a polycation formed by the connection of two [Mn(2,2-bipy)(2)](2+) complex cation and a (As(V)S(4))(3-) anion acts as a countercation for a polythioarsenate anion, [As(III)S(S(5))](-). The title compounds exhibit optical gaps in the range 1.58-2.48 eV and blue photoluminescence. Interestingly, compound 1 displays a weak second harmonic generation (SHG) response being about 1/21 times of KTP (KTiOPO(4)). Magnetic measurements show paramagnetic behavior for 1 and dominant antiferromagnetic behavior for 2-5. Of particular interest is 4, which is the first manganese chalcogenide showing spin-canting characteristic.
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Structure, composition and mechanical properties of the silk fibres of the egg case of the Joro spider, Nephila clavata (Araneae, Nephilidae).
J. Biosci.
PUBLISHED: 11-26-2011
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The silk egg case and orb web of spiders are elaborate structures that are assembled from a number of components. We analysed the structure, the amino acid and fibre compositions, and the tensile properties of the silk fibres of the egg case of Nephila clavata. SEM shows that the outer and inner covers of the egg case consist of thick, medium and thin silk fibres. The silk fibres of the outer cover of the egg case are probably produced by the major and minor ampullate glands. The silk fibres of the inner cover of the egg case from cylindrical glands appears to be distinct from the silk fibres of the major ampullate glands based on their micro-morphology, mole percent amino acid composition and types, and tensile behaviour and properties. Collectively, our investigations show that N. clavata uses silk fibres from relatively few glands in varying combinations to achieve different physical and chemical properties (e.g., color, diameter, morphology and amino acid composition) and functional and mechanical properties in the different layers of the egg case.
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Caltubin, a novel molluscan tubulin-interacting protein, promotes axonal growth and attenuates axonal degeneration of rodent neurons.
J. Neurosci.
PUBLISHED: 10-28-2011
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Axotomized central neurons of most invertebrate species demonstrate a strong regenerative capacity, and as such may provide valuable molecular insights and new tools to promote axonal regeneration in injured mammalian neurons. In this study, we identified a novel molluscan protein, caltubin, ubiquitously expressed in central neurons of Lymnaea stagnalis and locally synthesized in regenerating neurites. Reduction of caltubin levels by gene silencing inhibits the outgrowth and regenerative ability of adult Lymnaea neurons and decreases local ?- and ?-tubulin levels in neurites. Caltubin binds to ?- and/or ?-tubulin in both Lymnaea and rodent neurons. Expression of caltubin in PC12 cells and mouse cortical neurons promotes NGF-induced axonal outgrowth and attenuates axonal retraction after injury. This is the first study illustrating that a xenoprotein can enhance outgrowth and prevent degeneration of injured mammalian neurons. These results may open up new avenues in molecular repair strategies through the insertion of molecular components of invertebrate regenerative pathways into mammalian neurons.
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X-Ray crystal structure of [HSm{V(IV)O(TPPS)}]n and encapsulation of nitrogen molecules in 1-D channels.
Dalton Trans
PUBLISHED: 10-19-2011
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The crystal structure of an N(2)-encapusulated MOF, which is stable under open-air conditions at ambient temperature, was determined by single-crystal X-ray diffraction at 123 K. The crystal MOF of [HSm{V(IV)O(TPPS)}](n) designed to have 1-D channels periodically constricted by porphyrins planes adsorbed N(2) at 77 K. The adsorbed N(2) molecules remained in the 1-D channels even after warming to ambient temperature. The single-crystal structure of [HSm{V(IV)O(TPPS)}](n)?N(2) determined by X-ray diffraction indicated that N(2) molecules trapped in the constricted parts block other N(2) molecules in 1-D channels from escaping from the MOF. Such a unique encapsulation mode provides a promising approach toward designing novel MOFs with high gas storage capacity at ambient temperature.
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Scatter-hoarding rodents as secondary seed dispersers of a frugivore-dispersed tree Scleropyrum wallichianum in a defaunated Xishuangbanna tropical forest, China.
Integr Zool
PUBLISHED: 09-14-2011
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Local extinction or population decline of large frugivorous vertebrates as primary seed dispersers, caused by human disturbance and habitat change, might lead to dispersal limitation of many large-seeded fruit trees. However, it is not known whether or not scatter-hoarding rodents as secondary seed dispersers can help maintain natural regeneration (e.g. seed dispersal) of these frugivore-dispersed trees in the face of the functional reduction or loss of primary seed dispersers. In the present study, we investigated how scatter-hoarding rodents affect the fate of tagged seeds of a large-seeded fruit tree (Scleropyrum wallichianum Arnott, 1838, Santalaceae) from seed fall to seedling establishment in a heavily defaunated tropical forest in the Xishuangbanna region of Yunnan Province, in southwest China, in 2007 and 2008. Our results show that: (i) rodents removed nearly all S. wallichianum seeds in both years; (ii) a large proportion (2007, 75%; 2008, 67.5%) of the tagged seeds were cached individually in the surface soil or under leaf litters; (iii) dispersal distance of primary caches was further in 2007 (19.6 ± 14.6 m) than that in 2008 (14.1 ± 11.6 m), and distance increased as rodents recovered and moved seeds from primary caches into subsequent caching sites; and (iv) part of the cached seeds (2007, 3.2%; 2008, 2%) survived to the seedling stage each year. Our study suggests that by taking roles of both primary and secondary seed dispersers, scatter-hoarding rodents can play a significant role in maintaining seedling establishment of S. wallichianum, and are able to at least partly compensate for the loss of large frugivorous vertebrates in seed dispersal.
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Indicating atmospheric sulfur by means of S-isotope in leaves of the plane, osmanthus and camphor trees.
Environ. Pollut.
PUBLISHED: 09-10-2011
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Foliar ?(34)S values of three soil-growing plant species (Platanus Orientalis L., Osmanthus fragrans L. and Cinnamomum camphora) have been analyzed to indicate atmospheric sulfur. The foliar ?(34)S values of the three plant species averaged -3.11±1.94‰, similar to those of both soil sulfur (-3.73±1.04‰) and rainwater sulfate (-3.07±2.74‰). This may indicate that little isotopic fractionation had taken place in the process of sulfur uptake by root or leaves. The ?(34)S values changed little in the transition from mature leaves to old/senescing leaves for both the plane tree and the osmanthus tree, suggestive of little isotope effect during sulfur redistribution in plant tissues. Significantly linear correlation between ?(34)S values of leaves and rainwater sulfate for the plane and osmanthus trees allowed the tracing of temporal variations of atmospheric sulfur by means of foliar sulfur isotope, while foliage ?(34)S values of the camphor is not an effective indicator of atmospheric sulfur.
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Different effects of a cotemplate and [(transition-metal)(1,10-phenanthroline)(m)]2+ (m = 1-3) complex cations on the self-assembly of a series of hybrid selenidostannates showing combined optical properties of organic and inorganic components.
Inorg Chem
PUBLISHED: 09-08-2011
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1,10-Phenanthroline (phen) and monoprotonated methylamine molecules were used as a novel cotemplate to direct the formation of a new inorganic-organic hybrid selenidostannate, (CH(3)NH(3))(4)(Sn(2)Se(6))·6phen (1); while the utilization of three types of transition-metal (TM) phen complex cations with the TM/phen ration of 1:1, 1:2, and 1:3 as structure directors affords {[Mn(phen)(2)](2)(?(2)-Sn(2)Se(6))}·H(2)O (2a), {[Fe(phen)(2)](2)(?(2)-Sn(2)Se(6))} (2b), {[Mn(phen)](2)(?(4)-Sn(2)Se(6))}(n) (3), {[Mn(phen)(2)](Sn(2)Se(5))}(n) (4), and [Fe(phen)(3)](n)(Sn(3)Se(7))(n)·1.25nH(2)O (5). These compounds show diverse structures with the selenidostannate anions varying from discrete, ?(2)- and ?(4)- (Sn(2)Se(6))(4-) anions, to one-dimensional (1-D) (1)(?)(Sn(2)Se(5)(2-)) anionic chains, and two-dimensional (2-D) extended (2)(?)(Sn(3)Se(7)(2-)) anionic layers, demonstrating different structure-directing abilities of the cotemplate and the three types of TM phen complex cations. This work clearly indicates that the approach of modifying the number of the free coordination sites of unsaturated TM phen complex cations is very exciting as a way to synthesize novel hybrid chalcogenidometalates. Of particular interest, the present compounds exhibit interesting optical properties that reflect the combined effects of both photoluminescence-active organic components and semiconducting inorganic chalcogenidometalate anionic networks.
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NADPH oxidase complex and IBD candidate gene studies: identification of a rare variant in NCF2 that results in reduced binding to RAC2.
Gut
PUBLISHED: 09-07-2011
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The NOX2 NADPH oxidase complex produces reactive oxygen species and plays a critical role in the killing of microbes by phagocytes. Genetic mutations in genes encoding components of the complex result in both X-linked and autosomal recessive forms of chronic granulomatous disease (CGD). Patients with CGD often develop intestinal inflammation that is histologically similar to Crohns colitis, suggesting a common aetiology for both diseases. The aim of this study is to determine if polymorphisms in NOX2 NADPH oxidase complex genes that do not cause CGD are associated with the development of inflammatory bowel disease (IBD).
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[Effect of Buyang Huanwut decoction on apoptosis of splenocytes in rats with sepsis].
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 09-01-2011
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To observe the change in number of spleen T lymphocyte, B lymphocyte, apoptotic splenocytes and the expression of Bcl-2 and Bax protein in rats with sepsis; to study the effect of Buyang Huanwu decoction (BYHWD) on the immune function in rats with sepsis.
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Tracing sources of coal combustion using stable sulfur isotope ratios in epilithic mosses and coals from China.
J Environ Monit
PUBLISHED: 06-15-2011
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In China, coal combustion is the most important source of atmospheric sulfur pollution. Moss sulfur isotopic signatures have been believed to hold source-specific information that can serve as a fingerprint to identify atmospheric sulfur sources. In cities where only local coals were combusted, we observed a good correspondence of average sulfur isotope ratios in urban mosses (Haplocladium microphyllum) to the values of local coals (?(coals) = 1.455?(mosses)- 3.945, R(2) = 0.975, p = 0.01). But if different types of coals were combusted, we did not know whether moss sulfur isotope ratios can indicate mixed coals. To confirm this, using a mixing model we estimated the ratios of imported coal to local coals at cities where both coals were used. We found that the estimated ratios at large cities (>1 million people) where both coals were used were similar to the reported ratios in their respective provinces. For small cities (<0.5 million people) in Jiangxi Province and other provinces, the estimated ratios were higher than the reported ratios because the relatively cheaper local coals were less used in all the small cities except in cities where local coal deposits were found nearby. The comparison results showed that moss sulfur isotope is a useful tool for indicating coal-derived sulfur even in cities where mixed coals were combusted.
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Development of a serotype colloidal gold strip using monoclonal antibody for rapid detection type Asia1 foot-and-mouth disease.
Virol. J.
PUBLISHED: 06-03-2011
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In this study, we developed a rapid, one step colloid gold strip (CGS) capable of specifically detecting type Asia1 foot-and-mouth disease virus (FMDV). We have produced two monoclonal antibodies (mAb) to type Asia1 FMD (named 1B8 and 5E2). On the test strip, the purified 1B8 labelled with the colloidal gold was used as the detector, and the purified 5E2 and goat anti-mouse antibodies were wrapped onto nitrocellulose (NC) membranes as the test and the control line, respectively. The rapid colloidal gold stereotype diagnostic strip was housed in a plastic case.
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Stabilization of noncondensed (As(III)S3)(3-) anions by coordinating to [Mn(II)(phen)](2+) complex cations: a mixed-valent thioarsenate (III, V) {[Mn(phen)]3(As(V)S4)(As(III)S3)}(n)·nH2O showing the coexistence of antiferromagnetic order, photoluminescenc
Inorg Chem
PUBLISHED: 05-20-2011
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A novel one-dimensional (1-D) mixed-valent thioarsenate (III, V), {[Mn(phen)](3)(As(V)S(4))(As(III)S(3))}(n)·nH(2)O (1), with a noncentrosymmetric (NCS) polar packing arrangement has been obtained under solvothermal conditions. The noncondensed (As(III)S(3))(3-) anion in 1 is stabilized by coordinating to [Mn(II)(phen)](2+) complex cations and exhibits an unprecedented ?(3)-1,2?S:2,3?S:3?S linkage mode. Compound 1 represents the first example of the stabilization of noncondensed (MQ(3))(3-) (M = As, Sb; Q = S, Se) species only in the coordination of TM(II) complex cations (TM = transition-metal) and the first observation of the coexistence of the (As(V)S(4))(3-) tetrahedron and the noncondensed (As(III)S(3))(3-) pyramid in a single compound. Of particular interest, compound 1 is also an antiferromagnet with T(N) = 31 K, and exhibits photoluminescence (PL) with a maximum emission at about 438 nm and a second harmonic generation (SHG) response.
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Develope monoclonal antibody against foot-and-mouth disease virus A type.
Virol Sin
PUBLISHED: 05-04-2011
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In order to develop an anti-FMDV A Type monoclonal antibody (mAb), BABL/c mice were immunized with FMDV A type. Monoclonal antibodies (mAbs) 7B11 and 8H4 against Foot-and-mouth disease virus (FMDV) serotype A were produced by fusing SP2/0 myeloma cells with splenocyte from the mouse immunized with A/AV88. The microneutralization titer of the mAbs 7B11 and 8H4 were 1024 and 512, respectively. Both mAbs contain kappa light chains, the mAbs were IgG1. In order to define the mAbs binding epitopes, the reactivity of these mAbs against A Type FMDV, were examined using indirect ELISA, the result showed that both mAbs reacted with A Type FMDV. These mAbs may be used for further vaccine studies, diagnostic methods, prophylaxis, etiological and immunological research on FMDV. Characterization of these ncindicated that prepared anti-FMDV A mAbs had no cross-reactivity with Swine Vesicular Disease (SVD) or FMDV O, Asia1 and C Type antigens. Their titers in abdomen liquor were 1:5×10(6) and 1:2×10(6), respectively. 7B11 was found to be of subtype IgG(1), 8H4 was classified as IgG(2b) subtype. The mAbs prepared in this study, are specific for detection of FMDV serotype A, and is potentially useful for pen-side diagnosis.
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Single nucleotide polymorphisms that increase expression of the guanosine triphosphatase RAC1 are associated with ulcerative colitis.
Gastroenterology
PUBLISHED: 04-16-2011
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RAC1 is a guanosine triphosphatase that has an evolutionarily conserved role in coordinating immune defenses, from plants to mammals. Chronic inflammatory bowel diseases are associated with dysregulation of immune defenses. We studied the role of RAC1 in inflammatory bowel diseases using human genetic and functional studies and animal models of colitis.
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Inorganic supramolecular compounds with 3-D chiral frameworks show potential as both mid-IR second-order nonlinear optical and piezoelectric materials.
J. Am. Chem. Soc.
PUBLISHED: 02-22-2011
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Two inorganic supramolecular compounds, (Hg(6)P(3))(In(2)Cl(9)) (1) and (Hg(8)As(4))(Bi(3)Cl(13)) (2), which have chiral 3-D host frameworks with guest moieties filling the helical tunnels, have been synthesized. They both have large second-harmonic generation efficiencies, and compound 2 also exhibits obvious single-crystal piezoelectric performance. Theoretical studies from first-principles calculations were performed on their nonlinear optical (NLO) and piezoelectric properties, and results indicate that good NLO and piezoelectric materials can be obtained by designing both complicated polycations and polyanions with large molecular polarizability as functional components rather than traditional single polyanions.
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High regeneration capacity helps tropical seeds to counter rodent predation.
Oecologia
PUBLISHED: 01-03-2011
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Rapid germination of non-dormant seeds is one adaptation plants have evolved to counter seed predation by rodents. Some rodent species have evolved behaviors that prevent or slow the seed germination process through seed embryo removal or seed pruning; however, no plant species is known to have successfully escaped embryo removal or seed pruning by rodents. Here, we report that the non-dormant seeds of Pittosporopsis kerrii Craib in tropical rain forests in China have a high regeneration capacity to counter seed pruning by rodents. We found seed pruning, instead of embryo removal, was commonly used by rodents to increase food storage time by slowing down the seed germination process, but that P. kerrii seeds have a high regeneration capacity to escape seed predation by rodents: all pruned seeds, pruned roots and embryo-removed seeds by rodents or people retain the ability to develop into seedlings. Seeds of P. kerrii also have other capacities (i.e. rapid seed decomposition and indigestible dormant taproots) to escape predation by reducing the plants attractiveness to rodents. The association between seed pruning behavior in rodents and high regeneration capacity of pruned seeds or roots in P. kerrii seeds are likely novel adaptation strategies adopted by seeds and rodents, respectively.
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Effect of ENSO-driven precipitation on population irruptions of the Yangtze vole Microtus fortis calamorum in the Dongting Lake region of China.
Integr Zool
PUBLISHED: 12-17-2010
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The Yangtze vole (Microtus fortis Buechner, 1889) is a small herbivore species that inhabits lake beaches in the Dongting Lake region along the Yangtze River in Southern China. Its population shows strong oscillations during the wet season due to summer precipitation-induced immigration away from the lake into adjacent rice fields. The effect of El Niño-Southern Oscillation-driven precipitation on population abundance and growth of the vole species is not fully understood. We undertook an analysis of the combined data of 4 time series covering 1981-2006 from 4 different sites and a separate analysis on a single time series (1981-2006) from one site. Our results demonstrate that a dual effect of El Niño-Southern Oscillation-driven precipitation on the population abundance of voles is time-dependent: precipitation in the current year has a positive effect, whereas precipitation in the previous year has a negative effect. The dual effect of precipitation on vole population is well explained by the unique interactions among vole population, precipitation water level and the lake beach habitat around Dongting Lake. We found that drier than average weather of the previous year benefited voles because their breeding habitats, lake beaches, were exposed for long stretches of time. Wet weather was found to increase the number of voles inhabiting rice fields because as the water level of the lake rose they were forced from beaches into surrounding rice fields. Summer precipitation in the Dongting Lake region was found to be positively associated with the sea surface temperature (SST) of the eastern tropical Pacific Ocean of the previous year and winter SST and spring SST of the current year. Annual rates of increase in the vole population of the reconstructed time series are negatively associated with the vole abundance and autumn precipitation of the previous year and winter precipitation of the current years. These results suggest that both extrinsic and density-dependent intrinsic factors may affect population dynamics of the Yangtze voles.
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Motor learning reduces eye movement variability through reweighting of sensory inputs.
J. Neurosci.
PUBLISHED: 12-03-2010
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Motor learning can improve both the accuracy and precision of motor performance. We analyzed changes in the average trajectory and the variability of smooth eye movements during motor learning in rhesus monkeys. Training with a compound visual-vestibular stimulus could reduce the variability of the eye movement responses without altering the average responses. This improvement of eye movement precision was achieved by shifting the reliance of the movements from a more variable, visual signaling pathway to a less variable, vestibular signaling pathway. Thus, cerebellum-dependent motor learning can improve the precision of movements by reweighting sensory inputs with different variability.
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[Effects of combined application of biogas residues and chemical fertilizers on greenhouse tomatos growth and its fruit yield and quality].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-01-2010
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With randomized block design, a field experiment was conducted in greenhouse to study the effects of combined application of biogas residues and chemical fertilizers on the tomato growth and its fruit yield and quality. The combined application of biogas residues and chemical fertilizers benefited the tomato growth and its fruit yield and quality. The yield of the combined application of 60% biogas residues and 40% chemical fertilizers were higher than the other treatments. The fruit quality under the application of 60% biogas residue and 40% chemical fertilizers also improved significantly, with the Vc content (91.09 mg x kg(-1)) and total sugar content being 21.32 mg x kg(-1) and 2.13% higher than the control, respectively. Among the test fertilization combinations, 60% biogas residue combined with 40% chemical fertilizers was the best one for greenhouse tomatos growth and its fruit yield and quality.
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Promising multiple-epitope recombinant vaccine against foot-and-mouth disease virus type O in swine.
Clin. Vaccine Immunol.
PUBLISHED: 11-17-2010
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In order to develop a completely safe immunogen to replace the traditional inactivated vaccine, a tandem-repeat multiple-epitope recombinant vaccine against foot-and-mouth disease (FMD) virus (FMDV) type O was developed. It contained three copies each of residues 141 to 160 and 200 to 213 of VP1 of the O/China/99 strain of FMDV coupled with a swine immunoglobulin G heavy-chain constant region (scIgG). The data showed that the multiple-epitope recombinant vaccine elicited high titers of anti-FMDV specific antibodies in swine at 30 days postvaccination (dpv) and conferred complete protection against a challenge with 10³ 50% swine infective doses of the O/China/99 strain. The anti-FMDV specific antibody titers were not significantly different between the multiple-epitope recombinant vaccine and the traditional vaccine (t test, P > 0.05). The number of 50% pig protective doses was 6.47, which is higher than the number recommended by the World Organization for Animal Health. The multiple-epitope recombinant vaccine resulted in a duration of immunity of at least 6 months. We speculate that the multiple-epitope recombinant vaccine is a promising vaccine that may replace the traditional inactivated vaccine for the prevention and control of FMD in swine in the future.
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Photochromic inorganic-organic hybrid: a new approach for switchable photoluminescence in the solid state and partial photochromic phenomenon.
Dalton Trans
PUBLISHED: 08-18-2010
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A photochromic inorganic-organic hybrid based on in situ generated MV(2+) cation (MV(2+) = methyl viologen = N,N-dimethyl-4,4-bipyridinium) has been obtained, in which a vagarious partial photochromic phenomenon together with its photoluminescence modulation properties are reported for the first time in the inorganic-organic hybrids.
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[Application of AAS to detecting the influence of railway on the soil of navel orange garden].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 08-17-2010
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Railway transportation has boosted the economy of railway road area, meanwhile it brings some undesirable impacts on the environment of the railway road area. The quality of the fruits is directly related with the elements of the soil, so understanding the element contents of soil in navel oranges garden in the vicinity of railway is meaningful to the security of agriculture products and ecological conditions in the areas surrounding the railways. As a favorite fruit, navel orange is widely planted around the railway in the south China, especially in Sichuan, Chongqing, Hubei, Jiangxi and Guizhou. The present paper studied the contents of Pb, Cd, Mn, Cu, Zn etc in the soil planting navel orange in the vicinity of Chengdu-Dazhou railway by AAS. The railway was built in 1997 and the research area was sited in Jintang county, Sichuan. The results showed that the contents of Pb and Mn in soil planting navel orange were significantly higher than those in the control soil, but the contents of Cd, Cu and Zn showed no significant difference.
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[Prokaryotic expression, protein purification and reactivity analysis of the VP1 and its C terminus of a South African isolate of FMDV serotype SAT2].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 07-13-2010
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To induce the expression of structure protein VP1 and its C terminus of foot-and-mouth disease virus (FMDV) serotype SAT2 in E.coli and analyze their reactivities with FMDV positive antiserum.
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Genetic alteration with variable intron/exon organization amongst five PI-homoeologous genes in Platanus acerifolia.
Gene
PUBLISHED: 07-04-2010
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Flower development has been extensively characterized in the model species Arabidopsis thaliana and Antirrhinum majus. However, there have been few studies in woody species. Here, we report the isolation and characterization of five PISTILLATA (PI) homoeologous genes (PaPI1-to-5) from the London Plane tree (Platanus acerifolia Willd). PaPI1 and PaPI2 show a similar genomic structure to other known PI homoeologs, but PaPI3/4/5 lack intron sequences. In addition, PaPI5 lacks the third, fourth and fifth exons which encode the K-domain. These altered gene copies may have originated as processed retrogenes. PaPI2 appears micro-regulated by alternative splicing, displaying three splice forms (PaPI2a, PaPI2b and PaPI2c). RT-PCR analysis showed different expression profiles and transcript abundance for the five PaPI genes. PaPI transcripts encoding full-length polypeptides were expressed predominantly in male/female inflorescences and PaPI2a was the most abundant transcript (59%) indicating that PaPI2 may be the major functional PI-homoeolog in London Plane. Phenotypic characterization in a heterologous expression system demonstrated that the full-length PaPI product functions as a B class gene. By contrast the PaPI5 form, which lacks the K-domain, had no apparent effect on flower development. In vitro studies also demonstrated that the K-domain is required to form PaPI/PaAP3 heterodimers.
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Detection of cytokeratin 19, human mammaglobin, and carcinoembryonic antigen-positive circulating tumor cells by three-marker reverse transcription-PCR assay and its relation to clinical outcome in early breast cancer.
Int. J. Biol. Markers
PUBLISHED: 06-30-2010
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To investigate the diagnostic, predictive, and prognostic value of the detection of circulating tumor cells (CTCs) using a three-marker (CK19, hMAM and CEA) RT-PCR assay in patients with early breast cancer.
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[Chemical characteristics of 9 d continuous precipitation in a typical polluted city: a case study of Guiyang, China].
Huan Jing Ke Xue
PUBLISHED: 06-10-2010
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A study of the continuous precipitation in Guiyang has been taken during October 30 and November 7. The results showed that the range of pH was between 3.65 and 7.20, and volume-weighted mean was 4.24. SO4(2-) was the main anion and volume-weighted mean was 119.06 microeq x L(-1), accounting for 80.63% of total anions. While Ca2+ was the main cation and volume-weighted mean was 48.87 microeq x L(-1), accounting for 48.16% of total cation and NH4+ was 38.38 microeq x L(-1), 37.82%. Good correlations between Mg2+, Ca2+, NH4+ and SO4(2-) are observed, which may exist as MgSO4, CaSO4 and (NH4)2SO4 in the rainwater in Guiyang City. Different ions of the atmosphere had different scavenged ways and rate in the precipitation process. In the initial stage of precipitation, the ions such as Mg2+, which were rich in coarse particles, were quickly removed from atmosphere. However the ions such as NH4+ and SO4(2-), which were rich in fine particles, could remain in the atmosphere for a longer time.
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De novo protein synthesis of syntaxin-1 and dynamin-1 in long-term memory formation requires CREB1 gene transcription in Lymnaea stagnalis.
Behav. Genet.
PUBLISHED: 05-27-2010
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Consolidation of aversive operant conditioning into long-term memory (LTM) requires CREB-dependent de novo protein synthesis. The newly synthesized proteins are distributed to the synapses in neurons that are involved in memory formation and storage. Accumulating evidence indicates that the presynaptic release mechanisms also play a role in long-term synaptic plasticity. Our understanding of whether the presynaptic proteins undergo de novo synthesis during long-term memory formation is limited. In this study, we investigated the involvement of syntaxin-1, a presynaptic exocytotic protein, and dynamin-1, an endocytotic protein, in the formation of long-term memory. We took advantage of a well-established aversive operant conditioning model of aerial respiratory behavior in the fresh water pond snail Lymnaea stagnalis, and demonstrated that the LTM formation is associated with increased expression of syntaxin-1 and dynamin-1, coincident with elevated levels of CREB1. Partial knockdown of CREB1 gene by double stranded RNA inhibition (dsRNAi) prior to operant conditioning prevented snails from memory consolidation, and reduced the expression of syntaxin-1 and dynamin-1 at both mRNA and protein levels. These findings suggest that CREB1-mediated gene expression is required for the LTM-induced up-regulation of synaptic proteins, syntaxin-1 and dynamin-1, in L. stagnalis. Our study thus offers new insights into the molecular mechanisms that mediate CREB1-dependent long-term memory formation.
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Surgically treated primary malignant tumor of small bowel: a clinical analysis.
World J. Gastroenterol.
PUBLISHED: 03-25-2010
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To evaluate the clinical presentation, treatment and survival of patients with primary malignant tumor of small bowel (PMTSB).
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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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