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Find video protocols related to scientific articles indexed in Pubmed.
Addition of optically pure H-phosphinate to ketones: selectivity, stereochemistry and mechanism.
Org. Biomol. Chem.
PUBLISHED: 10-20-2014
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Aromatic methyl ketones and cyclic asymmetric ketones underwent hydrophosphorylation with P-stereogenic H-P species in the presence of potassium carbonate to produce P,C-stereogenic tertiary ?-hydroxyl phosphinates in excellent yields with up to 99?:?1 dr. The diastereoselectivity was induced by a reversible conversion of less stable stereomer of product to that of a more stable one via an equilibrium, which was confirmed by aldehyde/ketone exchanging reaction. Toward the exchange, aliphatic or aldehyde carbonyl were more active than aromatic or ketone carbonyls, respectively. The stability difference between the two diastereomers was controlled by the sizes of substituents linking to phosphorus or ?-carbon.
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Real-time Noninvasive Monitoring of UV Light-induced Cell Death by the Deflection of a Probe Beam.
Anal Sci
PUBLISHED: 10-15-2014
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Cell death and its deregulation characterize numerous human diseases. Here, we report on real-time noninvasive monitoring of UV light-induced cell death by the deflection of a probe beam. UV light of 330 - 370 nm from a high-pressure Hg lamp illuminated cultured HepG2 cells, and at the same time a probe beam from a diode laser was passed through a vicinity of the HepG2 cell. The deflection signal of the probe beam, which was induced by changes of the concentration gradients in processes of the active materials movements across the cell membrane, was monitored. It was found that the deflection signals changed greatly after UV illumination, suggesting that the materials movements across the cell membrane were greatly affected by the UV illumination. After UV illumination of about 5400 - 7400 s at a light power of 0.028 W/cm(2), the deflection signals became little changed with time, suggesting that the living cells had been killed by the UV illumination. This conclusion agreed well with cell viability determinations of the traditional trypan blue method.
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Comparison of tissue sample processing methods for harvesting the viral metagenome and a snapshot of the RNA viral community in a turkey gut.
J. Virol. Methods
PUBLISHED: 09-01-2014
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RNA viruses have been associated with enteritis in poultry and have been isolated from diseased birds. The same viral agents have also been detected in healthy flocks bringing into question their role in health and disease. In order to understand better eukaryotic viruses in the gut, this project focused on evaluating alternative methods to purify and concentrate viral particles, which do not involve the use of density gradients, for generating viral metagenome data. In this study, the sequence outcomes of three tissue processing methods have been evaluated and a data analysis pipeline has been established for RNA viruses from the gastrointestinal tract. In addition, with the use of the best method and increased sequencing depth, a glimpse of the RNA viral community in the gastrointestinal tract of a clinically normal 5-week old turkey is presented. The viruses from the Reoviridae and Astroviridae families together accounted for 76.3% of total viruses identified. The rarefaction curve at the species level further indicated that majority of the species diversity was included with the increased sequencing depth, implying that viruses from other viral families were present in very low abundance.
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[Research advances on ADAM28 expression and ADAM28-mediated tumor metastasis].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 08-19-2014
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A disintegrin-metalloproteinase 28 (ADAM28) is one of important members of ADAM family, that is involved in various biological events including cell adhesion, proteolysis, growth and metastasis of solid tumors and hematological malignancies. Studies have shown that ADAM28 is highly expressed in several human tumors, such as lung, breast and bladder cancers, and chronic lymphocytic leukemia, and its tissue expression levels correlate with cancer metastasis. ADAM28-mediated cancer cell metastasis may be related with the cleavage of von Willebrand's factor (vWF), insulin-like growth factor binding protein-3 (IGFBP-3) and connective tissue growth factor (CTGF), as well as the promoting PSGL-1/P-selectin-mediated cell adhesion. This review summarizes the basic and translational aspects of ADAM28 biology that might stimulate the interest in ADAM28 research and discovery of novel ADAM28 targets, providing potential novel therapies for metastatic cancers.
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Contribution of effluent organic matter (EfOM) to ultrafiltration (UF) membrane fouling: isolation, characterization, and fouling effect of EfOM fractions.
Water Res.
PUBLISHED: 08-08-2014
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EfOM has been regarded as a major organic foulant resulting in UF membrane fouling in wastewater reclamation. To investigate fouling potential of different EfOM fractions, the present study isolated EfOM into hydrophobic neutrals (HPO-N), colloids, hydrophobic acids (HPO-A), transphilic neutrals and acids (TPI), and hydrophilics (HPI), and tested their fouling effect in both salt solution and pure water during ultrafiltration (UF). Major functional groups and chemical structure of the isolates were identified using Fourier transform infrared spectroscopy (FT-IR) and solid-state carbon nuclear magnetic resonance ((13)C NMR) analysis. The influence of the isolation process on the properties of EfOM fractions was minor because the raw and reconstituted secondary effluents were found similar with respect to UV absorbance, molecular size distribution, and fluorescence character. In membrane filtration tests, unified membrane fouling index (UMFI) and hydraulic resistance were used to quantify irreversible fouling potential of different water samples. Results show that under similar DOC level in feed water, colloids present much more irreversible fouling than other fractions. The fouling effect of the isolates is related to their size, chemical properties, and solution chemistry. Further investigations have identified that the interaction between colloids and other fractions also influences the performance of colloids in fouling phenomena.
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[Role of ERK/FoxO3a signal axis in inhibitory effect of vitexin 1 (VB-1) in HepG2 cell proliferation].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 07-12-2014
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To investigate whether the ERK/FoxO3a signal axis could induce the inhibitory effect of vitexin 1 (VB-1) in HepG2 cell proliferation.
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16?,17?-Epoxypregnenolone-20-oxime prevent LPS-induced NO production and iNOS expression in BV-2 microglial cells by inhibiting JNK phosphorylation.
Biol. Pharm. Bull.
PUBLISHED: 07-04-2014
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The free radical nitric oxide (NO), a main member of neuroinflammatory cytokine and a gaseous molecule produced by activated microglia, has many physiological functions, including neuroinflammation. In the present study, we evaluated the effects of serial 16-dehydropregnenolone-3-acetate derivatives on lipopolysaccharide (LPS)-induced NO production and inducible nitric oxide synthase (iNOS) expression in BV-2 microglial cells. Among the six derivatives tested, the increases in NO production and iNOS expression observed in BV-2 microglial cells after LPS stimulation were significantly inhibited by treatment with 16?, 17?-epoxypregnenolone-20-oxime. Moreover, the inhibitory effect of 16?,17?-epoxypregnenolone-20-oxime on NO production was similar to that of S-methylisothiourea sulfate (SMT), an iNOS inhibitor. Further studies showed that 16?,17?-epoxypregnenolone-20-oxime inhibited c-Jun N-terminal kinase (JNK) phosphorylation but not inhibitor kappa B (I?B)-? degradation. Our data in LPS-stimulated microglia cells suggest that 16?,17?-epoxypregnenolone-20-oxime might be a candidate therapeutic for treatment of NO induced neuroinflammation and could be a novel iNOS inhibitor.
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GSK-3?-regulated N-acetyltransferase 10 is involved in colorectal cancer invasion.
Clin. Cancer Res.
PUBLISHED: 06-30-2014
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NAT10 (N-acetyltransferase 10) is a nucleolar protein, but may show subcellular redistribution in colorectal carcinoma. In this study, we evaluated membranous staining of NAT10 in colorectal carcinoma and its clinical implications, and explored the mechanism of regulation of NAT10 redistribution.
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PKG and NHR-49 signalling co-ordinately regulate short-term fasting-induced lysosomal lipid accumulation in C. elegans.
Biochem. J.
PUBLISHED: 05-24-2014
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Lysosomes act as terminal degradation organelles to hydrolyse macromolecules derived from both the extracellular space and the cytoplasm. In Caenorhabditis elegans fasting induces the lysosomal compartment to expand. However, the molecular and cellular mechanisms for this stress response remain largely unclear. In the present study, we find that short-term fasting leads to increased accumulation of polar lipids in lysosomes. The fasting response is co-ordinately regulated by EGL-4, the C. elegans PKG (protein kinase G) orthologue, and nuclear hormone receptor NHR-49. Further results demonstrate that EGL-4 acts in sensory neurons to enhance lysosomal lipid accumulation through inhibiting the DAF-3/SMAD pathway, whereas NHR-49 acts in intestine to inhibit lipids accumulation via activation of IPLA-2 (intracellular membrane-associated calcium-independent phospholipase A2) in cytoplasm and other hydrolases in lysosomes. Remarkably, the lysosomal lipid accumulation is independent of autophagy and RAB-7-mediated endocytosis. Taken together, our results reveal a new mechanism for lysosomal lipid metabolism during the stress response, which may provide new clues for investigations of lysosome function in energy homoeostasis.
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Effect of gradient decompression on the occurrence of intraoperative hypotension and prognosis in traumatic brain injury.
Turk Neurosurg
PUBLISHED: 05-17-2014
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To investigate the effect of gradient decompression on the occurrence of intraoperative hypotension and prognosis in traumatic brain injury. MATERIAL and
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A new type of carbon nitride-based polymer composite for enhanced photocatalytic hydrogen production.
Chem. Commun. (Camb.)
PUBLISHED: 05-17-2014
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A new type of graphitic C3N4-based composite photocatalysts was designed and prepared by co-loading PEDOT as a hole transport pathway and Pt as an electron trap on C3N4. The as-prepared C3N4-PEDOT-Pt composites showed drastically enhanced activity for visible light-driven photocatalytic H2 production compared to those of C3N4-PEDOT and C3N4-Pt, possibly due to the spatial separation of the reduction and oxidation reaction sites.
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Cellular scent of influenza virus infection.
Chembiochem
PUBLISHED: 04-09-2014
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Volatile organic compounds (VOCs) emanating from humans have the potential to revolutionize non-invasive diagnostics. Yet, little is known about how these compounds are generated by complex biological systems, and even less is known about how these compounds are reflective of a particular physiological state. In this proof-of-concept study, we examined VOCs produced directly at the cellular level from B lymphoblastoid cells upon infection with three live influenza virus subtypes: H9N2 (avian), H6N2 (avian), and H1N1 (human). Using a single cell line helped to alleviate some of the complexity and variability when studying VOC production by an entire organism, and it allowed us to discern marked differences in VOC production upon infection of the cells. The patterns of VOCs produced in response to infection were unique for each virus subtype, while several other non-specific VOCs were produced after infections with all three strains. Also, there was a specific time course of VOC release post infection. Among emitted VOCs, production of esters and other oxygenated compounds was particularly notable, and these may be attributed to increased oxidative stress resulting from infection. Elucidating VOC signatures that result from the host cells response to infection may yield an avenue for non-invasive diagnostics and therapy of influenza and other viral infections.
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Roles of viroplasm-like structures formed by nonstructural protein NSs in infection with severe fever with thrombocytopenia syndrome virus.
FASEB J.
PUBLISHED: 03-05-2014
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Severe fever with thrombocytopenia syndrome (SFTS) virus is an emerging bunyavirus that causes a hemorrhagic fever with a high mortality rate. The virus is likely tick-borne and replicates primarily in hemopoietic cells, which may lead to disregulation of proinflammatory cytokine induction and loss of leukocytes and platelets. The viral genome contains L, M, and S segments encoding a viral RNA polymerase, glycoproteins G(n) and G(c), nucleoprotein (NP), and a nonstructural S segment (NSs) protein. NSs protein is involved in the regulation of host innate immune responses and suppression of IFN?-promoter activities. In this article, we demonstrate that NSs protein can form viroplasm-like structures (VLSs) in infected and transfected cells. NSs protein molecules interact with one another, interact with NP, and were associated with viral RNA in infected cells, suggesting that NSs protein may be involved in viral replication. Furthermore, we observed that NSs-formed VLS colocalized with lipid droplets and that inhibitors of fatty acid biosynthesis decreased VLS formation or viral replication in transfected and infected cells. Finally, we have demonstrated that viral dsRNAs were also localized in VLS in infected cells, suggesting that NSs-formed VLS may be implicated in the replication of SFTS bunyavirus. These findings identify a novel function of nonstructural NSs in SFTSV-infected cells where it is a scaffolding component in a VLS functioning as a virus replication factory. This function is in addition to the role of NSs protein in modulating host responses that will broaden our understanding of viral pathogenesis of phleboviruses.
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Synthesis and Anti-cancer Activities of Apigenin Derivatives.
Med Chem
PUBLISHED: 02-28-2014
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A novel series of apigenin derivatives with phloroglucinol or resorcinol as raw materials were synthesized according to Baker-Venaktaraman reaction and their in vitro inhibitory activities on colorectal adenocarcinoma (HT-29) and leucocythemia (HL-60) cell lines were evaluated by the standard methyl thiazole tetrazolium (MTT) method. The results of biological test showed that some of apigenin derivatives possessed stronger anti-cancer activities than apigenin. Compound 6 showed the strongest activity against colorectal adenocarcinoma (HT-29) and leucocythemia (HL-60) cell lines with IC50 valure of 2.03±0.22 µM, 2.25±0.42 µM, it was better than 5-FU (12.92±0.61 µM, 9.56±0.16 µM), which shows a potential compound for colorectal adenocarcinoma and leucocythemia.
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Abnormal expression of synaptophysin, SNAP-25, and synaptotagmin 1 in the hippocampus of kainic acid-exposed rats with behavioral deficits.
Cell. Mol. Neurobiol.
PUBLISHED: 02-27-2014
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Temporal lobe epilepsy is characterized by spontaneous recurrent seizures (SRS) and associated with behavioral problems. However, the molecular mechanisms underlying these problems are not yet clear. In this study, kainic acid (KA) was systemically administered to immature male Wistar rats to induce SRS. The behavior of the immature rats was evaluated with a water maze, elevated-plus mazes, and open field tests. The expression patterns of synaptophysin, SNAP-25, and synaptotagmin 1 (Syt 1) were examined by reverse-transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis. KA-treated rats with SRS demonstrated learning and memory deficits, reduced anxiety, and increased locomotor activity, compared with placebo-treated rats and KA-treated rats without SRS. No neuronal cell loss was observed in the hippocampus 6 weeks after exposure to KA. However, RT-PCR and Western blot analyses revealed decreased synaptophysin, SNAP-25, and Syt 1 expression in KA-treated rats with SRS. Synaptophysin, SNAP-25, and Syt1 expression levels were found to be positively correlated with learning and memory but negatively correlated with anxiety and locomotor activity. These data suggested that SRS may induce changes in synaptophysin, SNAP-25, and Syt1 expression and may be functionally related to SRS-induced behavioral deficits.
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Changes in seismic anisotropy shed light on the nature of the Gutenberg discontinuity.
Science
PUBLISHED: 02-27-2014
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The boundary between the lithosphere and asthenosphere is associated with a platewide high-seismic velocity "lid" overlying lowered velocities, consistent with thermal models. Seismic body waves also intermittently detect a sharp velocity reduction at similar depths, the Gutenberg (G) discontinuity, which cannot be explained by temperature alone. We compared an anisotropic tomography model with detections of the G to evaluate their context and relation to the lithosphere-asthenosphere boundary (LAB). We find that the G is primarily associated with vertical changes in azimuthal anisotropy and lies above a thermally controlled LAB, implying that the two are not equivalent interfaces. The origin of the G is a result of frozen-in lithospheric structures, regional compositional variations of the mantle, or dynamically perturbed LAB.
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An inactivated recombinant rabies CVS-11 virus expressing two copies of the glycoprotein elicits a higher level of neutralizing antibodies and provides better protection in mice.
Virus Genes
PUBLISHED: 02-05-2014
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The rabies virus (RABV) G protein is the primary contributor to the pathogenicity and protective immunity of RABV. In this study, we generated a recombinant rCVS-11-G strain containing two copies of the G protein derived from the pathogenic wild-type (wt) CVS-11 strain and based on its infectious clone. Compared with the wtCVS-11 strain, the rCVS-11-G strain possessed a larger virion and 1.4-fold more G protein, but it exhibited a similar growth property to the rCVS-11 strain, including passaging stability in vitro. qPCR results showed that the two G genes were over-expressed in BHK-21 cells infected with the rCVS-11-G strain. However, the rCVS-11-G strain presented an 80 % lower LD50 than the wtCVS-11 strain when intracranially (i.c.) inoculated in adult mice. Adult mice that were either intracranially (i.c.) or intramuscularly (i.m.) inoculated with rCVS-11-G strain developed more acute neurological symptoms and greater mortality than those inoculated with the wtCVS-11 strain. Furthermore, the rCVS-11-G strain was more easily and rapidly taken up by neuroblastoma cells. These data indicated that the rCVS-11-G strain might have increased neurotropism because of the over-expression of the pathogenic G protein. The inactivated rCVS-11-G strain induced significantly higher levels of virus neutralization antibodies and provided better protection from street rabies virus challenge in mice. Therefore, the rCVS-11-G strain may be a promising inactivated vaccine strain due to its better immunogenicity.
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Selection of an aptamer against rabies virus: a new class of molecules with antiviral activity.
Virus Res.
PUBLISHED: 01-15-2014
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Rabies is a fatal central nervous system (CNS) disease caused by the neurotropic rabies virus (RABV). The therapeutic management of RABV infections is still problematic, and novel antiviral strategies are urgently required. We established the RVG-BHK-21 cell line, which expresses RABV glycoprotein on the cell surface, to select aptamers. Through 28 iterative rounds of selection, single-stranded DNA (ssDNA) aptamers were generated by exponential enrichment (SELEX). A virus titer assay and a real-time quantitative reverse transcription PCR (qRT-PCR) assay revealed that four aptamers could inhibit the replication of RABV in cultured baby hamster kidney (BHK)-21 cells. However, the aptamers did not inhibit the replication of other virus, e.g., canine distemper virus (CDV) and canine parvovirus (CPV). In addition, the GE54 aptamer was found to effectively protect mice against lethal RABV challenge. After inoculation with aptamers for 24h or 48h, followed by inoculation with CVS-11, approximately 25-33% of the mice survived. In summary, we selected aptamers that could significantly protect from a lethal dose of RABV in vitro and in vivo.
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Lactobacillus pentosus strain LPS16 produces lactic acid, inhibiting multidrug-resistant Helicobacter pylori.
J Microbiol Immunol Infect
PUBLISHED: 01-09-2014
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Helicobacter pylori is a human gastric pathogen. Antibiotic resistance of H. pylori has become a problem increasing the failure of H. pylori eradication. Therefore alternative approaches are required. The aim of this study was to evaluate the anti-H. pylori activity of Lactobacillus pentosus strain LPS16 and the mechanism of its killing effect.
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Two new susceptibility loci 1q24.2 and 11p11.2 confer risk to severe acne.
Nat Commun
PUBLISHED: 01-09-2014
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Severe acne is a chronic inflammatory skin disorder characterized by widespread inflammatory lesions including nodules, cysts and potential scarring. Here we perform the first genome-wide association study of severe acne in a Chinese Han population comprising 1,056 cases and 1,056 controls using the Illumina HumanOmniZhongHua-8 BeadChip. In an independent cohort of 1,860 cases and 3,660 controls of Chinese Han, we replicate 101 SNPs of which 3 showed consistent association. We identify two new susceptibility loci at 11p11.2 (DDB2, rs747650, P(combined)=4.41 × 10?? and rs1060573, P(combined)=1.28 × 10??) and 1q24.2 (SELL, rs7531806, P(combined)=1.20 × 10??) that are involved in androgen metabolism, inflammation processes and scar formation in severe acne. These results point to new genetic susceptibility factors and suggest several new biological pathways related to severe acne.
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The sustained-release behavior and in vitro and in vivo transfection of pEGFP-loaded core-shell-structured chitosan-based composite particles.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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Novel submicron core-shell-structured chitosan-based composite particles encapsulated with enhanced green fluorescent protein plasmids (pEGFP) were prepared by complex coacervation method. The core was pEGFP-loaded thiolated N-alkylated chitosan (TACS) and the shell was pH- and temperature-responsive hydroxybutyl chitosan (HBC). pEGFP-loaded TACS-HBC composite particles were spherical, and had a mean diameter of approximately 120 nm, as measured by transmission electron microscopy and particle size analyzer. pEGFP showed sustained release in vitro for >15 days. Furthermore, in vitro transfection in human embryonic kidney 293T and human cervix epithelial cells, and in vivo transfection in mice skeletal muscle of loaded pEGFP, were investigated. Results showed that the expression of loaded pEGFP, both in vitro and in vivo, was slow but could be sustained over a long period. pEGFP expression in mice skeletal muscle was sustained for >60 days. This work indicates that these submicron core-shell-structured chitosan-based composite particles could potentially be used as a gene vector for in vivo controlled gene transfection.
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Gate leakage current induced trapping in AlGaN/GaN Schottky-gate HFETs and MISHFETs.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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This study examined the correlation between the off-state leakage current and dynamic on-resistance (RON) transients in AlGaN/GaN heterostructure field-effect transistors (HFETs) with and without a gate insulator under various stress conditions. The RON transients in a Schottky-gate HFET (SGHFET) and metal-insulator-semiconductor HFET (MISHFET) were observed after applying various amounts of drain-source bias stress. The gate insulator in the MISHFET effectively reduced the electron injection from the gate, thereby mitigating the degradation in dynamic switching performance. However, at relaxation times exceeding 10 ms, additional detrapping occurred in both the SGHFET and MISHFET when the applied stress exceeded a critical voltage level, 50 V for the SGHFET and 60 V for MISHFET, resulting in resistive leakage current build-up and the formation of hot carriers. These high-energy carriers acted as ionized traps in the channel or buffer layers, which subsequently caused additional trapping and detrapping to occur in both HFETs during the dynamic switching test conducted.
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STR DNA genotyping of hydatidiform moles in South China.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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To evacuate whether short-tandem-repeat (STR) DNA genotyping is effective for diagnostic measure to precisely classify hydatidiform moles.
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Canine parvovirus VP2 protein expressed in silkworm pupae self-assembles into virus-like particles with high immunogenicity.
PLoS ONE
PUBLISHED: 01-01-2014
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The VP2 structural protein of parvovirus can produce virus-like particles (VLPs) by a self-assembly process in vitro, making VLPs attractive vaccine candidates. In this study, the VP2 protein of canine parvovirus (CPV) was expressed using a baculovirus expression system and assembled into parvovirus-like particles in insect cells and pupae. Electron micrographs of VLPs showed that they were very similar in size and morphology when compared to the wild-type parvovirus. The immunogenicity of the VLPs was investigated in mice and dogs. Mice immunized intramuscularly with purified VLPs, in the absence of an adjuvant, elicited CD4(+) and CD8(+) T cell responses and were able to elicit a neutralizing antibody response against CPV, while the oral administration of raw homogenates containing VLPs to the dogs resulted in a systemic immune response and long-lasting immunity. These results demonstrate that the CPV-VLPs stimulate both cellular and humoral immune responses, and so CPV-VLPs may be a promising candidate vaccine for the prevention of CPV-associated disease.
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Evasion of antiviral immunity through sequestering TBK1/IKK{epsilon}/IRF3 into viral inclusion bodies.
J. Virol.
PUBLISHED: 12-11-2013
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Cells are equipped with pattern recognition receptors (PRRs) such as the toll-like and RIG-I-like receptors that mount innate defenses against viruses. However, viruses have evolved multiple strategies to evade or thwart host antiviral responses. Viral inclusion bodies (IBs), which are accumulated aggregates of viral proteins, are commonly formed during the replication of some viruses in infected cells, but their role in viral immune evasion has rarely been explored. Severe fever with thrombocytopenia syndrome (SFTS) is an emerging febrile illness caused by a novel phlebovirus in the Bunyaviridae. The SFTS viral nonstructural protein NSs can suppress host IFN? responses. NSs can form IBs in infected and transfected cells. Through interaction with tank-binding kinase 1 (TBK1), viral NSs was able to sequester the IKK complex, including IKK? and IRF3 into IBs, although NSs did not interact with IKK? or IRF3 directly. When cells were infected with influenza A virus, IRF3 was phosphorylated and active p-IRF3 was translocated into the nucleus. In the presence of NSs, IRF3 could still be phosphorylated, but p-IRF3 was trapped in cytoplasmic IBs, resulting in reduced IFN? induction and enhanced viral replication. Sequestration of the IKK complex and active IRF3 into viral IBs through the interaction of NS and TBK1 is a novel mechanism for viral evasion of innate immunity.
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[A study of relationship between dialectical classification according to traditional Chinese medicine of acute coronary syndrome with serum osteoprotegerin and its ligand].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 11-15-2013
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To investigate the relationship between osteoprotegerin (OPG) system and acute coronary syndrome (ACS) and its classification according to traditional Chinese medicine (TCM).
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Porous titania nanosheet/nanoparticle hybrids as photoanodes for dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 11-11-2013
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Porous titania nanohybrids (NHs) were successfully prepared by hybridizing the exfoliated titania nanosheets with anatase TiO2 nanoparticles. Various characterizations revealed that the titania NHs as photoanodes play a trifunctional role (light harvesting, dye adsorption, and electron transfer) in improving the efficiency (?) of the dye-sensitized solar cells. The optimized photoanode consisting layered NHs demonstrated a high overall conversion efficiency of 10.1%, remarkably enhanced by 29.5% compared to that (7.8%) obtained from the benchmark P25 nanoparticles under the same testing conditions.
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Purified vitexin compound 1 induces apoptosis through activation of FOXO3a in hepatocellular carcinoma.
Oncol. Rep.
PUBLISHED: 09-13-2013
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We previously reported that purified vitexin compound 1 (VB1, a neolignan from the seed of Chinese herb Vitex negundo) exhibited antitumor activity in cancer cell lines and xenograft models. In the present study, we examined the molecular mechanisms by which activation of the FOXO3a transcription factor mediated VB1-induced apoptosis in hepatocellular carcinoma (HCC) cells. The effects of VB1 on the proliferation of HCC cell lines HepG2, Hep3B, Huh-7 and human embryo liver L-02 cells were investigated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptotic death in HepG2 cells was examined using an enzyme-linked immunosorbent assay (ELISA) detection kit, flow cytometry after propidium iodide (PI) staining, and by DNA agarose gel electrophoresis. Caspase activity was measured using ELISA. The AKT/FOXO3a and ERK/FOXO3a pathways were analyzed using western blotting. VB1 inhibited human HCC cell proliferation in a concentration-dependent manner and increased the percentage of sub-G1 population HepG2 cells. Histone/DNA fragmentation and active caspase-3, -8 and -9 levels increased in a concentration-dependent manner and a DNA ladder was formed. The phosphorylation of AKT and ERK1/2 were inhibited and FOXO3a transcription factor was activated, resulting in apoptotic death. Knockdown of AKT1 by small interfering RNA (siRNA) and the MEK1/2 inhibitor, PD98059, enhanced VB1-induced apoptosis and FOXO3a transcriptional activity. Suppression of FOXO3a expression by siRNA inhibited VB1-induced apoptosis. VB1 induced expression of Bim, TRAIL, DR4 and DR5. Activation of the FOXO3a transcription factor appears to mediate pro-apoptotic effects of VB1 by inhibiting the AKT and ERK pathways.
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Cytokine and Chemokine Levels in Patients Infected With the Novel Avian Influenza A (H7N9) Virus in China.
J. Infect. Dis.
PUBLISHED: 08-29-2013
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H7N9 avian influenza is an emerging viral disease in China caused by avian influenza A (H7N9) virus. We investigated host cytokine and chemokine profiles in serum samples of H7N9 patients by multiplex-microbead immunoassays. Statistical analysis showed that IP-10, IL-6, IL-17, and IL-2 were increased in H7N9 infected patients. Furthermore, IL-6 and the chemokine IP-10 were significantly higher in severe H7N9 patients compared to nonsevere H7N9 cases. We suggest that proinflammatory cytokine responses, characterized by a combined Th1/Th17 cytokine induction, are partially responsible for the disease progression of patients with H7N9 infection.
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Novel bunyavirus in domestic and captive farmed animals, Minnesota, USA.
Emerging Infect. Dis.
PUBLISHED: 08-23-2013
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We tested blood samples from domestic and captive farmed animals in Minnesota, USA, to determine exposure to severe fever with thrombocytopenia syndrome virus and Heartland-like virus. We found antibodies against virus nucleoproteins in 10%-18% of samples from cattle, sheep, goats, deer, and elk in 24 Minnesota counties.
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Antidepressant desipramine leads to C6 glioma cell autophagy: implication for the adjuvant therapy of cancer.
Anticancer Agents Med Chem
PUBLISHED: 08-06-2013
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Depression is the most common psychiatric syndrome in cancer patients and adversely affects anti-cancer immune system and life quality of patients. Antidepressant desipramine (DMI) is clinically prescribed in the auxiliary treatment of cancer patients. Increasing evidences suggest that DMI has a broad spectrum of target-off biological effects, such as anticancer properties. Our previous study revealed that DMI at the clinical relevant concentrations could induce CHOP-dependent apoptotic death in C6 glioma cells. In this study, we further explored the pro-autophagic effect of DMI in C6 glioma cells and its underlying mechanism. Treatment with DMI could induce autophagic cell death characterized by the formation of autophagosome and the elevated level of autophagic protein Beclin-1 and cellular redistribution of marker LC3. Meanwhile, DMI inhibited the activation of PI3K-AKT-mTOR pathway which is considered as a negative regulator of autophagy. Furthermore, DMI activated PERK-eIF2? and ATF6 of endoplasmic reticulum (ER) stress pathway, while knockdown of PERK with the PERK-specific short interfering RNA (siRNA) could obviously attenuate the autophagy. The results strongly suggested that DMI could induce autophagy through the PERK-ER stress pathway in C6 glioma cells. Our findings provided new insights into another beneficial potential of antidepressant DMI in the adjuvant therapy of cancer.
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Invasive hypermucoid variant of group A Streptococcus is defective in growth and susceptible to DNA-damaging treatments.
Pathog Dis
PUBLISHED: 07-31-2013
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Hyaluronic acid capsule is one of the most important virulence factors of group A Streptococcus (GAS). Over-production of capsule has been thought to enhance GAS virulence during infections. However, although the increased of capsule expression associates with increased bacterial virulence and invasive ability, over-production of capsule has not often been observed among clinical isolates. In the present study, we identified two mucoid emm12 type isolates that can convert to the hypermucoid morphology under both in vitro and in vivo conditions. Consistent with previous studies, hypermucoid variants are more invasive in the mouse air-pouch infection model. However, one of the hypermucoid variants showed a growth-defective phenotype in regular broth culture conditions and is significantly more susceptible to various DNA-damaging treatments when compared with the mucoid variant. These properties of the hypermucoid variant may be adverse factors inhibiting its adaptation to the host environment during infections.
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Calcium-binding capacity of wheat germ protein hydrolysate and characterization of Peptide-calcium complex.
J. Agric. Food Chem.
PUBLISHED: 07-29-2013
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This study investigates the ability of various wheat germ protein hydrolysates (WGPHs) to bind calcium and characterizes the peptide-calcium complexes. We demonstrate that the amount of Ca bound depended greatly on the type of enzyme, degree of hydrolysis (DH), amino acid composition, and molecular mass distribution of different hydrolysates. The maximum level of Ca bound (67.5 mg·g(-1)) occurred when Alcalase was used to hydrolyze wheat germ protein at a DH of 21.5%. Peptide fragments exhibiting high calcium-binding capacity had molecular mass <2000 Da. The calcium-binding peptides mainly consisted of Glu, Arg, Asp, and Gly, and the level of Ca bound was related to the hydrophobic amino acid content in WGPHs. UV-visible and Fourier transform infrared spectra demonstrate that amino nitrogen atoms and oxygen atoms on the carboxyl group were involved in complexation. Therefore, wheat germ protein is a promising protein source for the production of calcium-binding peptides and could be utilized as a bioactive ingredient for nutraceutical food production.
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The genus Gnaphalium L. (Compositae): phytochemical and pharmacological characteristics.
Molecules
PUBLISHED: 06-18-2013
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The genus Gnaphalium, a herb distributed worldwide, comprises approximately 200 species of the Compositae (Asteraceae) family that belongs to the tribe Gnaphalieae. Some species are traditionally used as wild vegetables and in folk medicine. This review focuses on the phytochemical investigations and biological studies of plants from the genus Gnaphalium over the past few decades. More than 125 chemical constituents have been isolated from the genus Gnaphalium, including flavonoids, sesquiterpenes, diterpenes, triterpenes, phytosterols, anthraquinones, caffeoylquinic acid derivatives, and other compounds. The extracts of this genus, as well as compounds isolated from it, have been demonstrated to possess multiple pharmacological activities such as antioxidant, antibacterial and antifungal, anti-complement, antitussive and expectorant, insect antifeedant, cytotoxic, anti-inflammatory, antidiabetic and antihypouricemic properties. The present review compiles the information available on this genus because of its relevance to food and ethnopharmacology and the potential therapeutic uses of these species.
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A scalable colloidal approach to prepare hematite films for efficient solar water splitting.
Phys Chem Chem Phys
PUBLISHED: 06-18-2013
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The development of technologically and economically viable strategies for large-scale fabrication of photoelectrodes is crucial for solar H2 production from photoelectrochemical water splitting. Herein, a low-cost and facile colloidal electrophoretic deposition approach was developed for scalable fabrication of hematite (?-Fe2O3) films. Large-sized uniform films (e.g. 80 mm × 70 mm) with tailored thickness and nanostructures can be easily prepared on conductive substrates within 2 minutes. The resultant films showed a high photocurrent of ?1.1 mA cm(-2) at 1.23 V(RHE) under standard AM 1.5G illumination, which is among the highest reported values achieved on hematite films prepared using other complex colloidal approaches. The present work will pave a new avenue for fabrication of efficient photoelectrodes toward practically viable solar H2 production.
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Stability Analysis of Time-Delay Neural Networks Subject to Stochastic Perturbations.
IEEE Trans Cybern
PUBLISHED: 06-13-2013
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This paper is concerned with the problem of mean-square exponential stability of uncertain neural networks with time-varying delay and stochastic perturbation. Both linear and nonlinear stochastic perturbations are considered. The main features of this paper are twofold: 1) Based on generalized Finsler lemma, some improved delay-dependent stability criteria are established, which are more efficient than the existing ones in terms of less conservatism and lower computational complexity; and 2) when the nonlinear stochastic perturbation acting on the system satisfies a class of Lipschitz linear growth conditions, the restrictive condition P < ?I (or the similar ones) in the existing results can be relaxed under some assumptions. The usefulness of the proposed method is demonstrated by illustrative examples.
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Severe fever with thrombocytopenia syndrome virus among domesticated animals, China.
Emerging Infect. Dis.
PUBLISHED: 05-08-2013
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To investigate the infections of severe fever with thrombocytopenia syndrome virus (SFTSV) in domesticated animals, we sampled a total of 3,039 animals in 2 counties in Shandong Province, Peoples Republic of China, from April to November 2011. SFTSV-specific antibodies were detected in 328 (69.5%) of 472 sheep, 509 (60.5%) of 842 cattle, 136 (37.9%) of 359 dogs, 26 (3.1%) of 839 pigs, and 250 (47.4%) of 527 chickens. SFTSV RNA was detected in all sampled animal species, but the prevalence was low, ranging from 1.7% to 5.3%. A cohort study in 38 sheep was conducted to determine when seroconversion to SFTSV occured. SFTSVs were isolated from sheep, cattle, and dogs and shared >95% sequence homology with human isolates from the same disease-endemic regions. These findings demonstrate that natural infections of SFTSV occur in several domesticated animal hosts in disease-endemic areas and that the virus has a wide host range.
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Roles of MicroRNAs in the Caenorhabditis elegans Nervous System.
J Genet Genomics
PUBLISHED: 04-12-2013
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The first microRNA was discovered in Caenorhabditis elegans in 1993, and since then, thousands of microRNAs have been identified from almost all eukaryotic organisms examined. MicroRNAs function in many biological events such as cell fate determination, metabolism, apoptosis, and carcinogenesis. So far, more than 250 microRNAs have been identified in C. elegans; however, functions for most of these microRNAs are still unknown. A small number of C. elegans microRNAs are associated with known physiological roles such as developmental timing, cell differentiation, stress response, and longevity. In this review, we summarize known roles of microRNAs in neuronal differentiation and function of C. elegans, and discuss interesting perspectives for future studies.
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The effect of avian influenza virus NS1 allele on virus replication and innate gene expression in avian cells.
Mol. Immunol.
PUBLISHED: 03-25-2013
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The NS1 gene encoded by Type A influenza virus circulates as two alleles, the A and B allele. The immunomodulatory properties of the NS1 A allele have been thoroughly examined; however, comparisons of allele function have been predominantly made in mammalian systems. Here we show that counter to the current understanding of allele function in mammals, the two alleles similarly regulate elements of the type I interferon (IFN) signaling pathway, including the interferon-inducible genes Mx and 2-5 oligoadenylate synthase (2-5 OAS), and IL-6, which share the same induction pathway as the interferons in embryo fibroblasts from chickens, turkeys or ducks. Replication of two reassortant viruses demonstrated that the B allele virus replicates more and to higher titers than the A allele virus in duck cells; however, the A allele virus replicates more in the cells from chickens and turkeys. Finally, chimeric constructs were used to identify a region of the NS1 gene that conferred the statistically significant differences in expression and replication observed between the alleles.
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Bifurcation and control in a neural network with small and large delays.
Neural Netw
PUBLISHED: 03-18-2013
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This paper investigates a neural network modeled by a scalar delay differential equation. The focus is placed upon the Hopf bifurcation generated by varying the interaction parameter. A general expression for the periodic solutions arising from the Hopf bifurcation is obtained, and the direction of the bifurcation is also determined. Then, our results are tested in the two limits of small and large delays. For small delays, it is shown that a Hopf bifurcation to sinusoidal oscillations emerges as long as the interaction parameter is large enough (bifurcation from infinity) (Rosenblat & Davis, 1979). For large delays, it is pointed out that the oscillation progressively changes from sine to square-wave (Chow, Hale, & Huang, 1992; Hale & Huang, 1994). Moreover, a time delayed feedback control algorithm is introduced to generate the Hopf bifurcation at a desired bifurcation point for our neural network model. It is shown that the linear gain regulates the onset of the bifurcation, while the nonlinear gains govern the direction and the stability of the periodic solutions generated from the Hopf bifurcation.
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Construction and application of biotin-poloxamer conjugate micelles for chemotherapeutics.
J Microencapsul
PUBLISHED: 03-14-2013
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Biotin was conjugated on poloxamer to prepare biotin-poloxamer (BP) conjugate micelles for chemotherapeutics. Epirubicin (EPI) was encapsulated in BP micelles. The EPI-loaded BP micelles were characterized in terms of size, ?-potential, morphology, drug loading, drug encapsulation and drug release. Marrow leukemic HL-60 cells were used for evaluating the in vitro cytotoxicity of EPI-loaded BP micelles. Nude mice were axillainoculated subcutaneously HL-60 cells to establish tumour model for investigating the inhibition effects of EPI-loaded BP micelles. From the results, the sizes of these nanoparticles were about 100?nm. Fluorescence microscope observation supported the enhanced cellular uptake of the micelles. The order of the inhibition on tumour volume growth was: EPI-loaded BP micelles >EPI-loaded MATP micelles >EPI-loaded poloxamer micelles >EPI. BP micelles showed significant antitumour activity and low toxicity, compared with the non-targeted micelles. With the advantage of EPR effect and tumour-targeting potential, BP conjugate micelles might be developed as a new system for chemotherapeutics.
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Direct sampling in air of capillary electrophoresis.
Anal Sci
PUBLISHED: 03-12-2013
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Capillary electrophoresis (CE) is usually off-line combined with an adsorption/desorption method to analyze gaseous or atmospheric samples. Here, we demonstrated direct sampling in the air of CE. The inlet end of a fused silica capillary filled with a pH 7.2 phosphate buffer was placed in the air for absorbing gaseous or volatile components, while the outlet end was immersed into a buffer vial at the low electric potential side. After a certain period of time, the inlet end was immersed into another buffer vial at the high electric potential side; CE was carried out by applying a high electric voltage of 20 kV. An UV-absorbance detector (wavelength, 254 nm) was used in CE. Evaporated vanillin in air was used as model gaseous sample. Experimental factors, such as a height difference between the inlet end and the outlet buffer, were investigated in detail. Fast detection of evaporated vanillin in indoor air was demonstrated.
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Lipoxin A(4) activates alveolar epithelial sodium channel, Na,K-ATPase, and increases alveolar fluid clearance.
Am. J. Respir. Cell Mol. Biol.
PUBLISHED: 03-09-2013
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Edema fluid resorption is critical for gas exchange, and both alveolar epithelial sodium channel (ENaC) and Na,K-ATPase are accredited with key roles in the resolution of pulmonary edema. Alveolar fluid clearance (AFC) was measured in in situ ventilated lungs by instilling isosmolar 5% BSA solution with Evans Blue-labeled albumin tracer (5 ml/kg) and measuring the change in Evans Blue-labeled albumin concentration over time. Treatment with lipoxin A4 and lipoxin receptor agonist (5(S), 6(R)-7-trihydroxymethyl 17 heptanoate) significantly stimulated AFC in oleic acid (OA)-induced lung injury, with the outcome of decreased pulmonary edema. Lipoxin A4 and 5(S), 6(R)-7-trihydroxymethyl 17 heptanoate not only up-regulated the ENaC ? and ENaC ? subunits protein expression, but also increased Na,K-ATPase ?1 subunit protein expression and Na,K-ATPase activity in lung tissues. There was no significant difference of intracellular cAMP level between the lipoxin A4 treatment and OA group. However, the intracellular cGMP level was significantly decreased after lipoxin A4 treatment. The beneficial effects of lipoxin A4 were abrogated by butoxycarbonyl-Phe-Leu-Phe-Leu-Ph (lipoxin A4 receptor antagonist) in OA-induced lung injury. In primary rat alveolar type II epithelial cells stimulated with LPS, lipoxin A4 increased ENaC ? and ENaC ? subunits protein expression and Na,K-ATPase activity. Lipoxin A4 stimulated AFC through activation of alveolar epithelial ENaC and Na,K-ATPase.
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Identification and functional analysis of a novel PRKAG2 mutation responsible for Chinese PRKAG2 cardiac syndrome reveal an important role of non-CBS domains in regulating the AMPK pathway.
J Cardiol
PUBLISHED: 02-28-2013
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PRKAG2 gene encodes the ?2 regulatory subunit of AMP-activated protein kinase (AMPK) that acts as a sensor of cellular energy status, and its germline mutations are responsible for PRKAG2 cardiac syndrome (PCS). The majority of missense mutations of cystathionine beta-synthase (CBS) domains found in PCS impair the binding activity of PRKAG2 to adenosine derivatives, and therefore lead to PRKAG2 function impairment and AMPK activity alteration, resulting in a familial syndrome of ventricular preexcitation, conduction defects, and cardiac hypertrophy. However, it is unclear about the PRKAG2 mutation in the non-CBS domain. Here, a Chinese family exhibiting the cardiac syndrome associated with a novel heterozygous PRKAG2 mutation (Gly100Ser) mapped to exon 3 encoding a non-CBS domain is described and the function of this novel mutation was investigated in vitro.
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Complete Genome Sequence of emm1 Streptococcus pyogenes A20, a Strain with an Intact Two-Component System, CovRS, Isolated from a Patient with Necrotizing Fasciitis.
Genome Announc
PUBLISHED: 02-07-2013
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Here, we announce the complete sequence of Streptococcus pyogenes A20. This strain was isolated from a patient with necrotizing fasciitis. Given that A20 harbors an intact two-component system, CovRS, the discovery of its genome sequence provides more insight into the pathogenesis of a pandemic emm1 strain.
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Deterioration of cardiac function after acute myocardial infarction is prevented by transplantation of modified endothelial progenitor cells overexpressing endothelial NO synthases.
Cell. Physiol. Biochem.
PUBLISHED: 02-06-2013
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Stem cell transplantation and gene therapies have been shown to attenuate myocardial dysfunction after myocardial infarction (AMI) in different acute and chronic animal models. The aim of this study was to assess the potential therapeutic efficacy of endothelial NO synthases (eNOS)-expressing endothelial progenitor cells (EPCs) on infarcted hearts.
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Robust antiviral responses to enterovirus 71 infection in human intestinal epithelial cells.
Virus Res.
PUBLISHED: 02-04-2013
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Enterovirus 71 (EV71) is a single-stranded RNA virus that belongs to Picornaviridae family. It causes the hand-foot-and-mouth disease and fatal neurological diseases in young children and infants. The mechanism of EV71 pathogenesis remains obscure. The intestinal tract is the initial site of EV71 replication, but no or only mild gastrointestinal symptoms are observed clinically, suggesting that host immune responses of the intestinal epithelium to EV71 may be unique, which, however, remains rarely investigated. In this study, we showed that human intestinal epithelial cells HT-29 were susceptible to EV71, and the infected cells exhibited cytopathic effects (CPEs) and were prone to apoptosis. TLR-7 and TLR-8 were induced significantly post infection and may be pivotal in the induction of IFN-? and host innate immune responses against EV71. Among proinflammatory responses in EV71-infected intestinal epithelial cells, IL-6, CCL5, and IP10 were up-regulated and may play a key role in intestinal pathogenicity. We examined extrinsic and intrinsic apoptotic pathways and found that both were activated in EV71 infection. The mitochondria-mediated intrinsic pathway may also be activated through Bid cleaved by active caspase-8. Robust induction of IFN-? in human intestinal epithelial cells contradicts the finding that IFN induction was suppressed in other types of the cells, suggesting that mild gastrointestinal symptoms may be the result of sufficient local antiviral inductions. Our study has demonstrated a unique way of antiviral responses in human gut different from other tissue cells in response to EV71, which may account for mild symptoms in intestinal tract. This finding will broaden our understanding of host defense mechanism and the pathogenesis of EV71 infection.
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Aptamers targeting rabies virus-infected cells inhibit viral replication both in vitro and in vivo.
Virus Res.
PUBLISHED: 01-17-2013
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Rabies is an acute fatal encephalitis disease that affects many warm-blooded mammals. The causative agent of the disease is Rabies virus (RABV). Currently, no approved therapy is available once the clinical signs have appeared. Aptamers, oligonucleotide ligands capable of binding a variety of molecular targets with high affinity and specificity, have recently emerged as promising therapeutic agents. In this study, sixteen high-affinity single-stranded DNA (ssDNA) aptamers were generated by cell-SELEX. Viral titer assays revealed aptamers could specifically inhibit the replication of RABV in cells but did not inhibit the replication of canine distemper virus or canine parvovirus. In addition, the FO21 and FO24 aptamers, with and without PEGylation, were found to effectively protect mice against lethal RABV challenge. When mice were inoculated with aptamers for 24h prior to inoculation with CVS-11, approximately 87.5% of the mice survived. Here, we report aptamers that could significantly protect the mice from a lethal dose of RABV in vitro and in vivo, as demonstrated by the results for survival rate, weight loss and viral titers. These results indicate that FO21 and FO24 aptamers are a promising agent for specific antiviral against RABV infections.
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Copper-catalyzed trifluoromethylation of alkenes with an electrophilic trifluoromethylating reagent.
Beilstein J Org Chem
PUBLISHED: 01-01-2013
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An efficient method for the copper-catalyzed trifluoromethylation of terminal alkenes with an electrophilic trifluoromethylating reagent has been developed. The reactions proceeded smoothly to give trifluoromethylated alkenes in good to excellent yields. The results provided a versatile approach for the construction of Cvinyl-CF3 bonds without using prefunctionalized substrates.
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Peroxide Responsive Regulator PerR of group A Streptococcus Is Required for the Expression of Phage-Associated DNase Sda1 under Oxidative Stress.
PLoS ONE
PUBLISHED: 01-01-2013
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The peroxide regulator (PerR) is a ferric uptake repressor-like protein, which is involved in adaptation to oxidative stress and iron homeostasis in group A streptococcus. A perR mutant is attenuated in surviving in human blood, colonization of the pharynx, and resistance to phagocytic clearance, indicating that the PerR regulon affects both host environment adaptation and immune escape. Sda1 is a phage-associated DNase which promotes M1T1 group A streptococcus escaping from phagocytic cells by degrading DNA-based neutrophil extracellular traps. In the present study, we found that the expression of sda1 is up-regulated under oxidative conditions in the wild-type strain but not in the perR mutant. A gel mobility shift assay showed that the recombinant PerR protein binds the sda1 promoter. In addition, mutation of the conserved histidine residue in the metal binding site of PerR abolished sda1 expression under hydrogen peroxide treatment conditions, suggesting that PerR is directly responsible for the sda1 expression under oxidative stress. Our results reveal PerR-dependent sda1 expression under oxidative stress, which may aid innate immune escape of group A streptococcus.
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Lipopolysaccharide-induced M2 to M1 macrophage transformation for IL-12p70 production is blocked by Candida albicans mediated up-regulation of EBI3 expression.
PLoS ONE
PUBLISHED: 01-01-2013
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Macrophages are heterogeneous cell populations that are present in all tissues. Macrophages can be divided into classically activated inflammatory macrophages (M1) and alternatively activated anti-inflammatory macrophages (M2). It has been generally accepted that M1 macrophages are polarised in an inflammatory environment to produce pro-inflammatory cytokines, whilst M2 macrophages are involved in anti-inflammation and aid tissue repair in wound healing. Bacterial endotoxin (lipopolysaccharide; LPS) is a potent factor in infection, which induces M1 macrophages resulting in higher levels of iNOS, TNF? and IL-12p70 which dictate inflammatory T cell responses. M2 macrophages can be transformed into M1 macrophages following LPS stimulation to promote inflammation. Candida albicans is a commensal fungal microorganism, which has been suggested to induce immune tolerance; however, the mechanism of C. albicans-induced immune tolerance has not been investigated in detail. IL-35 is a recently identified anti-inflammatory cytokine which is a heterodimeric protein consisting of the Epstein-Barr virus-induced gene 3 (EBI3) and IL-12p35. IL-35 shares the protein subunit p35, with IL-12p70. IL-12p70 is the most potent cytokine to induce Th1 responses during inflammation. In this study, we demonstrate that heat-killed C. albicans (HKC) strongly suppressed LPS-induced IL-12p70 production in M2 macrophages. Candida albicans induced a high level of EBI3 expression in M2 macrophages, which served as a mechanism for IL-12p70 suppression by competitive binding of the common protein subunit (p35) of IL-35 and IL-12p70. To demonstrate that EBI3 expression had the ability to block IL-12p70 production intracellularly, a Chinese Hamster Ovary (CHO) cell line with biscistronic expression of IL-12p40 and p35 was constructed, followed by ectopic over-expression of EBI3. The over-expression of EBI3 in the IL-12p70 producing cell line effectively suppressed IL-12p70 production. IL-35 secretion was also detected in the cell line, with suppressed IL-12p70 production by immune-precipitation Western blotting. However, this secretion was not evident in M2 macrophages following stimulation by HKC. This can be explained by the constitutive expression of IL-35 receptors (gp130 and IL-12R?2) in M2 macrophages for cytokine consumption. Our results have indicated that C. albicans can suppress host inflammatory responses in mucosal skin by suppressing LPS-induced IL-12p70 production. Lower IL-12p70 production may avoid an unnecessary Th1 response in order to retain immune tolerance, which may be one of the mechanisms by which C. albicans achieves a successful commensal lifestyle without having a detrimental effect on the hosts health.
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[Detecting the concentrations of bisphenol A (BPA) in air of workplaces with HPLC].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 12-05-2011
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To establish the method of detecting the concentrations of bisphenol A (BPA)in air of workplaces with high performance liquid chromatographic (HPLC).
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[Effects of applying controlled release fertilizers on N2O emission from a lateritic red soil].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-01-2011
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Static closed chamber technique and contrast method were adopted to study the effects of three coated compound fertilizers (N:P2O5:K2O = 19:8.6:10.5, high N; 14.4:14.4:14.4, balanced NPK; and 12.5:9.6:20.2, high K) on the NO2O emission from a lateritic red soil under the condition of no crop planting, taking uncoated compound fertilizers (N:P2O5:K2O = 20:9:11, high N; 15:15:15, balanced NPK; and 13:10:21, high K) as the contrasts. Different formula of fertilizer NPK induced significant difference in the N2O emission. Under the application of uncoated compound fertilizers, the cumulative N2O emission was in the order of balanced NPK > or = high N > high K. Applying coated compound fertilizers decreased the N2O emission significantly, and the emission amount under the application of high N, balanced NPK, and high K was 34.4%, 30.5%, and 89.3% of the corresponding uncoated compound fertilizers, respectively. Comparing with the application of uncoated compound fertilizers, applying coated compound fertilizers also decreased the daily N2O flux significantly, and delayed and shortened the N2O peak, suggesting that coated fertilizers could reduce soil nitrogen loss and the global warming potential induced by N2O emission.
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[EGFR gene copy number, ERCC1 and BRCA1 protein expression and their relationship in non-small cell lung cancer].
Zhonghua Zhong Liu Za Zhi
PUBLISHED: 11-19-2011
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To evaluate the expression of epidermal growth factor receptor (EGFR) gene copy number and the expression of ERCC1 and BRCA1 proteins in patients with non-small-cell lung cancer (NSCLC) and the correlation between them.
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[Study on spectra properties of novel octa-substituted phthalocyanines].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 10-20-2011
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The spectrum properties of four novel 1, 4, 8, 11, 15, 18, 22, 25-octaoxybutyl copper phthalocyanine; 1,4,8,11,15,18, 22, 25-octamethoxybutanoate manganese phthalocyanine; 1, 4, 8, 11, 15, 18, 22, 25-octamethoxybutanoate copper phthalocyanine; 1, 4, 8, 11, 15, 18, 22, 25-octamethoxybutanoate zinc phthalocyanine were investigated by infrared, fluorescence and UV-visible spectrum in the the paper. There is no rule in the infrared spectrum of these octa-substituted phthalocyanines. The orders of the Q band, B band and Pc dimer band are different among the above Octa-substituted Phthalocyanines in the UV and fluorescence spectra. The reason is related to the interaction between the ligand and the central metal of these octa-substituted phthalocyanines.
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Delay-slope-dependent stability results of recurrent neural networks.
IEEE Trans Neural Netw
PUBLISHED: 10-06-2011
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By using the fact that the neuron activation functions are sector bounded and nondecreasing, this brief presents a new method, named the delay-slope-dependent method, for stability analysis of a class of recurrent neural networks with time-varying delays. This method includes more information on the slope of neuron activation functions and fewer matrix variables in the constructed Lyapunov-Krasovskii functional. Then some improved delay-dependent stability criteria with less computational burden and conservatism are obtained. Numerical examples are given to illustrate the effectiveness and the benefits of the proposed method.
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[Research progress on the molecular pathogenesis of Trichomonas vaginalis].
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi
PUBLISHED: 10-06-2011
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Trichomonas vaginalis is one of the most common human sexually transmitted pathogens that colonize the urogenital mucosa. This paper reviews those factors in the molecular pathogenesis of the parasite, including cell adhesin, interaction with fibronectin and laminin, G-proteins, pore-forming protein and proteinases.
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Barretts esophagus: prevalence and incidence of adenocarcinomas.
Ann. N. Y. Acad. Sci.
PUBLISHED: 09-29-2011
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The following on prevalence and incidence of adenocarcinomas in Barretts esphophagus (BE) includes commentaries on the mechanisms of a potential protective effect of proton pump inhibitors (PPIs) on progression of BE to high-grade dysplasia; evaluation of the role of PPIs in decreasing the risk of degeneration; the geographical variations of incidence of BE; the role of the nonmorphologic biomarkers; the relationship between length of BE and development of cancer; the confounding factors in incidence rates of BE; the role of the increase of cell differentiation and apoptosis induced by PPIs in the diminution of cancer risk; the frequency of occult neoplastic foci and unsuspected invasive cancer in surgical specimens; the influence on the indications of endoscopic therapy; the overestimation of regression in surgical series; attempts to evaluate the reasons for variations of cancer incidence in the literature; and progress in screening and surveillance for BE.
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Photocatalytic water oxidation on F, N co-doped TiO2 with dominant exposed {001} facets under visible light.
Chem. Commun. (Camb.)
PUBLISHED: 09-26-2011
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Visible-light-responsive anatase TiO(2) platelets with dominant {001} facets were prepared via a facile nitridation reaction from a TiOF(2) precursor. The in situ co-doping of N and F in the anatase TiO(2) nanoparticles leads to drastically enhanced absorption and excellent water oxidation performance in the visible light region.
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Coordination of multiple agents with double-integrator dynamics under generalized interaction topologies.
IEEE Trans Syst Man Cybern B Cybern
PUBLISHED: 09-12-2011
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The problem of the convergence of the consensus strategies for multiple agents with double-integrator dynamics is studied in this paper. The investigation covers two kinds of different settings. In the setting with the interaction topologies for the position and velocity information flows being modeled by different graphs, some sufficient conditions on the fixed interaction topologies are derived for the agents to reach consensus. In the setting with the interaction topologies for the position and velocity information flows being modeled by the same graph, we systematically investigate the consensus algorithm for the agents under both fixed and dynamically changing directed interaction topologies. Specifically, for the fixed case, a necessary and sufficient condition on the interaction topology is established for the agents to reach (average) consensus under certain assumptions. For the dynamically changing case, some sufficient conditions are obtained for the agents to reach consensus, where the condition imposed on the dynamical topologies is shown to be more relaxed than that required in the existing literature. Finally, we demonstrate the usefulness of the theoretical findings through some numerical examples.
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[Effect on PGF2alpha in plasma in primary dysmenorrhea treated with eye acupuncture].
Zhongguo Zhen Jiu
PUBLISHED: 09-08-2011
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To observe the clinical curative effect of primary dysmenorrhea and the content of prostaglandin F2alpha (PGF2alpha) in peripheral blood of menstrual periods treated with eye acupuncture therapy.
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Environmental pH changes, but not the LuxS signalling pathway, regulate SpeB expression in M1 group A streptococci.
J. Med. Microbiol.
PUBLISHED: 09-02-2011
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The autoinducer-2/LuxS signalling pathway participates in quorum sensing in diverse bacterial species. In group A streptococci (GAS), LuxS has been shown to be involved in regulating the expression of several important virulence factors. Streptococcal pyrogenic exotoxin B (SpeB), a cysteine protease that has important roles in GAS pathogenesis, is positively regulated by LuxS in M3 and M5 strains. In the present study, it was found that the supernatant harvested from an overnight culture stimulated M1 strains to express speB. However, mutation of the luxS gene in M1 strains or treating M1 strains with luxS mutant culture supernatant did not affect speB expression, indicating that the LuxS pathway is not involved in regulation of speB expression in M1 strains. In addition, the acid property of culture broth was found to be able to stimulate M1 strains to express speB in the same LuxS-independent manner. These results indicate that speB expression in M1 strains is induced by environmental pH changes but is not regulated by the LuxS signalling pathway.
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Determination of Bis(9)-(-)-Meptazinol, a bis-ligand for Alzheimers disease, in rat plasma by liquid chromatography-tandem mass spectrometry: application to pharmacokinetics study.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 09-01-2011
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A rapid, simple and sensitive LC-MS/MS method was developed and validated for the determination of Bis(9)-(-)-Meptazinol (B9M) in rat plasma. Protein precipitation method was used for sample preparation, using five volumes of methanol as the precipitation agent. The analytes were separated by a Zorbax Extend-C18 column with the mobile phase of methanol-water (containing 5mM ammonium formate, pH 9.8) (95:5, v/v), and monitored by positive electrospray ionization in multiple reaction monitoring (MRM) mode. Retention time of IS (Bis(5)-(-)-Meptazinol) and B9M were 1.9 min and 3.3 min, respectively. The limit of detection was 0.1 ng/ml and the linear range was 1-500 ng/ml. The relative standard deviation (RSD) of intra-day and inter-day variation was 4.4-6.2% and 6.2-8.9%, respectively. The extraction recoveries of B9M in plasma were over 95%. The method proved to be applicable to the pharmacokinetic study of B9M in rat after intravenous and subcutaneous administration.
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(7R,8S,9S,12S)-1-Benz-yloxy-13,14-didehydro-12-hy-droxy-2,13-dimeth-oxy-N-methyl-morphinane.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 08-13-2011
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In the title compound, C(26)H(31)NO(4), a sinomenine derivative, the angle between the two aromatic rings is 53.34?(4)°. The N-containing ring is in a chair conformation, while the other two non-planar rings are in a half-boat conformation. In the crystal, mol-ecules are linked by O-H?N inter-actions into a C(8) chain along [100].
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Stability and L2 performance analysis of stochastic delayed neural networks.
IEEE Trans Neural Netw
PUBLISHED: 08-12-2011
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This brief focuses on the robust mean-square exponential stability and L(2) performance analysis for a class of uncertain time-delay neural networks perturbed by both additive and multiplicative stochastic noises. New mean-square exponential stability and L(2) performance criteria are developed based on the delay partition Lyapunov-Krasovskii functional method and generalized Finsler lemma which is applicable to stochastic systems. The analytical results are established without involving any model transformation, estimation for cross terms, additional free-weighting matrices, or tuning parameters. Numerical examples are presented to verify that the proposed approach is both less conservative and less computationally complex than the existing ones.
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(7R,8S,9S,12S)-1-(4-Chloro-benz-yloxy)-13,14-didehydro-12-hy-droxy-2,13-dimeth-oxy-N-methyl-morphinane.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 08-03-2011
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The title compound, C(26)H(30)ClNO(4), a sinomenine derivative, has five six-membered rings, two of which are aromatic, with a dihedral angle of 34.13?(20)° between these. The N-containing ring and the fourth ring exhibit chair conformations, while the fifth ring approximates an envelope conformation. A single inter-molecular O-H?N hydrogen-bonding inter-action gives a one-dimensional chain structure which extends along the a axis. The absolute configuration for the mol-ecule has been determined.
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Elevated plasma levels of adropin in heart failure patients.
Intern. Med.
PUBLISHED: 08-01-2011
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Recent studies have suggested that a higher body mass index (BMI) is associated with an improved prognosis in heart failure (HF). Adropin is a recently identified protein that has been implicated in the maintenance of energy homeostasis. In the present study, we investigated plasma adropin levels in patients with HF and evaluated the relationship between the levels and the severity of HF.
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Cloning and molecular characterization of a mitogen-activated protein kinase gene from Poncirus trifoliata whose ectopic expression confers dehydration/drought tolerance in transgenic tobacco.
J. Exp. Bot.
PUBLISHED: 07-21-2011
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The mitogen-activated protein kinase (MAPK) cascade plays pivotal roles in diverse signalling pathways related to plant development and stress responses. In this study, the cloning and functional characterization of a group-I MAPK gene, PtrMAPK, in Poncirus trifoliata (L.) Raf are reported. PtrMAPK contains 11 highly conserved kinase domains and a phosphorylation motif (TEY), and is localized in the nucleus of transformed onion epidermal cells. The PtrMAPK transcript level was increased by dehydration and cold, but was unaffected by salt. Transgenic overexpression of PtrMAPK in tobacco confers dehydration and drought tolerance. The transgenic plants exhibited better water status, less reactive oxygen species (ROS) generation, and higher levels of antioxidant enzyme activity and metabolites than the wild type. Interestingly, the stress tolerance capacity of the transgenic plants was compromised by inhibitors of antioxidant enzymes. In addition, overexpression of PtrMAPK enhanced the expression of ROS-related and stress-responsive genes under normal or drought conditions. Taken together, these data demonstrate that PtrMAPK acts as a positive regulator in dehydration/drought stress responses by either regulating ROS homeostasis through activation of the cellular antioxidant systems or modulating transcriptional levels of a variety of stress-associated genes.
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Copper-mediated trifluoromethylation of arylboronic acids by trifluoromethyl sulfonium salts.
Chem. Commun. (Camb.)
PUBLISHED: 07-19-2011
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The ligand-free trifluoromethylation of arylboronic acids with a [Ph(2)SCF(3)](+)[OTf](-)/Cu(0) system has been carefully investigated. Aryl-, alkenyl- and heteroarylboronic acids with a variety of functional groups were suitable substrates for this reaction. It is suggested that a CuCF(3) species is formed under the reaction conditions.
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What is Visualize?

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

How does it work?

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

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

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