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Find video protocols related to scientific articles indexed in Pubmed.
Identification of Causative Pathogens in Mouse Eyes with Bacterial Keratitis by Sequence Analysis of 16S rDNA Libraries.
Exp. Anim.
PUBLISHED: 10-15-2014
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The clone library method using PCR amplification of the 16S ribosomal RNA (rRNA) gene was used to identify pathogens from corneal scrapings of C57BL/6-corneal opacity (B6-Co) mice with bacterial keratitis. All 10 samples from the eyes with bacterial keratitis showed positive PCR results. All 10 samples from the normal cornea showed negative PCR results. In all 10 PCR-positive samples, the predominant and second most predominant species accounted for 20.9% to 40.6% and 14.7% to 26.1%, respectively, of each clone library. The predominant species were Staphylococcus lentus, Pseudomonas aeruginosa, and Staphylococcus epidermidis. The microbiota analysis detected a diverse group of microbiota in the eyes of B6-Co mice with bacterial keratitis and showed that the causative pathogens could be determined based on percentages of bacterial species in the clone libraries. The bacterial species detected in this study were mostly in accordance with results of studies on clinical bacterial keratitis in human eyes. Based on the results of our previous studies and this study, the B6-Co mouse should be considered a favorable model for studying bacterial keratitis.
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Indium-mediated asymmetric intramolecular allenylation of N-tert-butanesulfinyl imines: efficient and practical access to chiral 3-allenyl-4-aminochromanes.
Org. Lett.
PUBLISHED: 07-28-2014
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An efficient method for the preparation of highly optically active 3-allenyl- and 3-vinyl-4-aminochromanes by In-mediated intramolecular cyclization has been developed. The synthetic utilities of the approach were demonstrated by the construction of various chiral polycyclic heterocycles, especially the interesting spiroheterocyclic compound 9 and steroid analogue 10.
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Immunogenicity of intradermal trivalent influenza vaccine with topical imiquimod: a double blind randomized controlled trial.
Clin. Infect. Dis.
PUBLISHED: 07-21-2014
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Imiquimod, a synthetic Toll-like receptor 7 agonist enhanced immunogenicity of influenza vaccine in a mouse model. We hypothesized that topical imiquimod before intradermal influenza vaccination (TIV) would produce similar effect in human.
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Development of reverse-transcription loop-mediated isothermal amplification assay for rapid detection of novel avian influenza A (H7N9) virus.
BMC Microbiol.
PUBLISHED: 03-16-2014
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BackgroundThe emerged human infection with avian influenza A (H7N9) virus in China since 2013 has aroused global concerns. There is great demand for simple and rapid diagnostic method for early detection of H7N9 to provide timely treatment and disease control. The aim of the current study was to develop a rapid, accurate and feasible reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay for detection of H7N9 virus.ResultsThe detection limits of the H7- and N9-specific RT-LAMP assay were both approximately 0.2 PFU per reaction. No cross-reactivity was observed with other subtype of influenza viruses or common respiratory viral pathogens. The assay worked well with clinical specimens from patients and chickens, and exhibited high specificity and sensitivity.ConclusionsThe H7/N9 specific RT-LAMP assay was sensitive and accurate, which could be a useful alternative in clinical diagnostics of influenza A (H7N9) virus, especially in the hospitals and laboratories without sophisticated diagnostic systems.
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Role of multi-detector computed tomography for biliary complications after liver transplantation.
World J. Gastroenterol.
PUBLISHED: 02-19-2014
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To investigate the diagnostic performance of multi-detector computed tomography (MDCT) in detecting biliary complications after orthotopic liver transplantation (OLT).
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Characterization of live-attenuated Japanese encephalitis vaccine virus SA14-14-2.
Vaccine
PUBLISHED: 02-14-2014
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The live attenuated Japanese encephalitis (JE) vaccine SA14-14-2 was licensed decades ago and now approved for clinical use in most JE endemic countries. Large-scale clinical trials demonstrate ideal safety and efficacy profile of this Chinese vaccine. The SA14-14-2 vaccine was derived from a virulent strain SA14 after hundreds of serial passaging in cells and animals, concern about virulence reversion remains exist. In the present study, to study the in vitro and in vivo genetic and attenuation stability of the vaccine virus, SA14-14-2 was serially passaged in Vero cells and mouse brain followed by sequence comparison and attenuation phenotype analysis. The results showed that no significant mutation was acquired after serial passaging in Vero cells except a single Ser66Leu mutation within capsid protein, which had no effect on viral virulence in mice. Importantly, serial passaging of SA14-14-2 in suckling mouse brain resulted in emergence of adaptive mutations and increased virulence in mice. Population and plaque-purified clone consensus sequence analysis showed four adaptive mutations in envelope (E) protein, F107L, K138E, T226R and I270T, sequentially occurred and become predominant during serial passaging in suckling mouse brain. Especially, these adaptive mutations were close related with the enhanced neurovirulence and neuroinvasiveness in mice. Our results provide experimental evidence of highly genetic and attenuation stability of SA14-14-2 following passaging in Vero cells, and reveal the potential virulence reversion during passaging in mouse brain in association with critical adaptive mutations in E protein. These findings are important for quality control and evaluation of live JE vaccines and will help understand the attenuation mechanism of flavivirus vaccine.
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A novel reporter system for neutralizing and enhancing antibody assay against dengue virus.
BMC Microbiol.
PUBLISHED: 02-12-2014
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Dengue virus (DENV) still poses a global public health threat, and no vaccine or antiviral therapy is currently available. Antibody plays distinct roles in controlling DENV infections. Neutralizing antibody is protective against DENV infection, whereas sub-neutralizing concentration of antibody can increase DENV infection, termed antibody-dependent enhancement (ADE). Plaque-based assay represents the most widely accepted method measuring neutralizing or enhancing antibodies.
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Toll-like receptor 7 agonist imiquimod in combination with influenza vaccine expedites and augments humoral immune responses against influenza A(H1N1)pdm09 virus infection in BALB/c mice.
Clin. Vaccine Immunol.
PUBLISHED: 02-12-2014
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Toll-like receptors (TLRs) of the innate immune system are known targets for enhancing vaccine efficacy. We investigated whether imiquimod, a synthetic TLR7 agonist, can expedite the immune response against influenza virus infection when combined with influenza vaccine. BALB/c mice were immunized intraperitoneally with monovalent A(H1N1)pdm09 vaccine combined with imiquimod (VCI) prior to intranasal inoculation with a lethal dose of mouse-adapted A(H1N1)pdm09 virus. For mice immunized 3 days before infection, the survival rates were significantly higher in the VCI group (60%, mean survival time[MST], 11 days) than in the vaccine-alone (30%; MST, 8.8 days), imiquimod-alone (5%; MST, 8.4 days), and phosphate-buffered saline (PBS) (0%; MST, 6.2 days) groups (P < 0.01). In the VCI group, 45 and 35% of the mice survived even when they were infected 2 days or 1 day after immunization. Virus-specific serum IgM, IgG, and neutralizing antibodies appeared earlier with higher geometric mean titers in the VCI group than in the control groups. The pulmonary viral load was significantly lower at all time points postinfection in the VCI, vaccine-alone, and imiquimod-alone groups than in the PBS control group (P < 0.05). The protection induced by VCI was specific for A(H1N1)pdm09 virus but not for A(H5N1) virus. Since imiquimod combined with RNase-treated vaccine is as protective as imiquimod combined with untreated vaccine, mechanisms other than TLR7 may operate in expediting and augmenting immune protection. Moreover, increased gamma interferon mRNA expression and IgG isotype switching, which are markers of the Th1 response induced by imiquimod, were not apparent in our mouse model. The mechanisms of imiquimod-induced immune protection deserve further study.
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Recombinant tandem multi-linear neutralizing epitopes of human enterovirus 71 elicited protective immunity in mice.
Virol. J.
PUBLISHED: 01-16-2014
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Human Enterovirus 71 (EV71) has emerged as the leading cause of viral encephalitis in children, especially in the Asia-Pacific regions. EV71 vaccine development is of high priority at present, and neutralization antibodies have been documented to play critical roles during in vitro and in vivo protection against EV71 infection.
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MicroRNA-21 (miR-21) regulates cellular proliferation, invasion, migration, and apoptosis by targeting PTEN, RECK and Bcl-2 in lung squamous carcinoma, Gejiu City, China.
PLoS ONE
PUBLISHED: 01-01-2014
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In South China (Gejiu City, Yunnan Province), lung cancer incidence and associated mortality rate is the most prevalent and observed forms of cancer. Lung cancer in this area is called Gejiu squamous cell lung carcinoma (GSQCLC). Research has demonstrated that overexpression of miR-21 occurs in many cancers. However, the unique relationship between miR-21 and its target genes in GSQCLC has never been investigated. The molecular mechanism involved in GSQCLC must be compared to other non-small cell lung cancers in order to establish a relation and identify potential therapeutic targets.
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In vitro characterization of human adenovirus type 55 in comparison with its parental adenoviruses, types 11 and 14.
PLoS ONE
PUBLISHED: 01-01-2014
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Human adenovirus type 55 (HAdV-B55) represents a re-emerging human pathogen, and this adenovirus has been reported to cause outbreaks of acute respiratory diseases among military trainees and in school populations around the world. HAdV-B55 has been revealed to have evolved from homologous recombination between human adenovirus type 14 (HAdV-B14) and type 11 (HAdV-B11), but it presents different clinical manifestations from parental virus HAdV-B11. In the present paper, we report the distinct biological features of HAdV-B55 in comparison with the parental viruses HAdV-B11 and HAdV-B14 in cell cultures. The results showed that HAdV-B55 replicated well in various cells, similar to HAdV-B11 and HAdV-B14, but that its processing had a slower and milder cytopathic effect in the early stages of infection. Viral fitness analysis showed that HAdV-B55 exhibited higher levels of replication in respiratory cells than did either of its parents. Cytotoxicity and apoptosis analyses in A549 cells indicated that HAdV-B55 was less cytotoxic than HAdV-B11 and HAdV-B14 were and induced milder apoptosis. Finally, thermal sensitivity analysis revealed that HAdV-B55 exhibited lower thermostability than did either HAdV-B11 or HAdV-B14, which may limit the transmission of HAdV-B55 in humans. Together, the findings described here expand current knowledge about this re-emerging recombinant HAdV, shedding light on the pathogenesis of HAdV-B55.
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Parallel mRNA and microRNA profiling of HEV71-infected human neuroblastoma cells reveal the up-regulation of miR-1246 in association with DLG3 repression.
PLoS ONE
PUBLISHED: 01-01-2014
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Human enterovirus 71 (HEV71) has emerged as the leading cause of viral encephalitis in children in most Asian countries. The roles of host miRNAs in the neurological pathogenesis of HEV71 infection remain unknown. In the present study, comprehensive miRNA expression profiling in HEV71-infected human neuroblastoma SH-SY5Y cells was performed using the Affymetrix Gene Chip microarray assay and was validated using real-time RT-PCR. Among the 69 differentially expressed miRNAs, miR-1246 was specifically induced by HEV71 infection in human neuroblastoma cells, but inhibition of miR-1246 failed to affect HEV71 replication. Parallel mRNA and microRNA profiling based on the 35 K Human Genome Array identified 182 differentially regulated genes. Target prediction of miR-1246 and network modeling revealed 14 potential target genes involved in cell death and cell signaling. Finally, a combined analysis of the results from mRNA profiling and miR-1246 target predication led to the identification of disc-large homolog 3 (DLG3), which is associated with neurological disorders, for further validation. Sequence alignment and luciferase reporter assay showed that miR-1246 directly bound with the 3'-UTR of DLG3 gene. Down-regulation of miR-1246 induced significant changes in DLG3 expression levels in HEV71-infected SHSY5Y cells. Together, these results suggested that miR-1246 might play a role in neurological pathogenesis of HEV71 by regulating DLG3 gene in infected cells. These findings provide new information on the miRNA and mRNA profiles of HEV71-infected neuroblastoma cells. The biological significance of miR-1246 and DLG3 during the course of HEV71 infection deserves further investigation.
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A modified nonlinear damage accumulation model for fatigue life prediction considering load interaction effects.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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Many structures are subjected to variable amplitude loading in engineering practice. The foundation of fatigue life prediction under variable amplitude loading is how to deal with the fatigue damage accumulation. A nonlinear fatigue damage accumulation model to consider the effects of load sequences was proposed in earlier literature, but the model cannot consider the load interaction effects, and sometimes it makes a major error. A modified nonlinear damage accumulation model is proposed in this paper to account for the load interaction effects. Experimental data of two metallic materials are used to validate the proposed model. The agreement between the model prediction and experimental data is observed, and the predictions by proposed model are more possibly in accordance with experimental data than that by primary model and Miner's rule. Comparison between the predicted cumulative damage by the proposed model and an existing model shows that the proposed model predictions can meet the accuracy requirement of the engineering project and it can be used to predict the fatigue life of welded aluminum alloy joint of Electric Multiple Units (EMU); meanwhile, the accuracy of approximation can be obtained from the proposed model though more simple computing process and less material parameters calling for extensive testing than the existing model.
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Induction of neutralizing antibodies against four serotypes of dengue viruses by MixBiEDIII, a tetravalent dengue vaccine.
PLoS ONE
PUBLISHED: 01-01-2014
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The worldwide expansion of four serotypes of dengue virus (DENV) poses great risk to global public health. Several vaccine candidates are under development. However, none is yet available for humans. In the present study, a novel strategy to produce tetravalent DENV vaccine based on envelope protein domain III (EDIII) was proposed. Tandem EDIIIs of two serotypes (type 1-2 and type 3-4) of DENV connected by a Gly-Ser linker ((Gly4Ser)3) were expressed in E. coli, respectively. Then, the two bivalent recombinant EDIIIs were equally mixed to form the tetravalent vaccine candidate MixBiEDIII, and used to immunize BALB/c mice. The results showed that specific IgG and neutralizing antibodies against all four serotypes of DENV were successfully induced in the MixBiEDIII employing Freund adjuvant immunized mice. Furthermore, in the suckling mouse model, sera from mice immunized with MixBiEDIII provided significant protection against four serotypes of DENV challenge. Our data demonstrated that MixBiEDIII, as a novel form of subunit vaccine candidates, might have the potential to be further developed as a tetravalent dengue vaccine in the near future.
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[Transarterial chemoembolization plus computed tomography-guided percutaneous radiofrequency ablation for small hepatocellular carcinoma in special locations].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 12-24-2013
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To evaluate the efficacy and safety of transcatheter arterial chemoembolization (TACE) plus computed tomography (CT)-guided percutaneous radiofrequency ablation (RFA) for small hepatocellular carcinoma (HCC) in special locations.
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Triazole-Dithiocarbamate Based Selective Lysine Specific Demethylase 1 (LSD1) Inactivators Inhibit Gastric Cancer Cell Growth, Invasion, and Migration.
J. Med. Chem.
PUBLISHED: 11-01-2013
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Lysine specific demethylase 1 (LSD1), the first identified histone demethylase, plays an important role in epigenetic regulation of gene activation and repression. The up-regulated LSD1s expression has been reported in several malignant tumors. In the current study, we designed and synthesized five series of 1,2,3-triazole-dithiocarbamate hybrids and screened their inhibitory activity toward LSD1. We found that some of these compounds, especially compound 26, exhibited the most specific and robust inhibition of LSD1. Interestingly, compound 26 also showed potent and selective cytotoxicity against LSD1 overexpressing gastric cancer cell lines MGC-803 and HGC-27, as well as marked inhibition of cell migration and invasion, compared to 2-PCPA. Furthermore, compound 26 effectively reduced the tumor growth bared by human gastric cancer cells in vivo with no signs of adverse side effects. These findings suggested that compound 26 deserves further investigation as a lead compound in the treatment of LSD1 overexpressing gastric cancer.
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A Chimeric Dengue Virus Vaccine using Japanese Encephalitis Virus Vaccine Strain SA14-14-2 as Backbone Is Immunogenic and Protective against Either Parental Virus in Mice and Nonhuman Primates.
J. Virol.
PUBLISHED: 10-09-2013
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The development of a safe and efficient dengue vaccine represents a global challenge in public health. Chimeric dengue viruses (DENV) based on an attenuated flavivirus have been well developed as vaccine candidates by using reverse genetics. In this study, based on the full-length infectious cDNA clone of the well-known Japanese encephalitis virus live vaccine strain SA14-14-2 as a backbone, a novel chimeric dengue virus (named ChinDENV) was rationally designed and constructed by replacement with the premembrane and envelope genes of dengue 2 virus. The recovered chimeric virus showed growth and plaque properties similar to those of the parental DENV in mammalian and mosquito cells. ChinDENV was highly attenuated in mice, and no viremia was induced in rhesus monkeys upon subcutaneous inoculation. ChinDENV retained its genetic stability and attenuation phenotype after serial 15 passages in cultured cells. A single immunization with various doses of ChinDENV elicited strong neutralizing antibodies in a dose-dependent manner. When vaccinated monkeys were challenged with wild-type DENV, all animals except one that received the lower dose were protected against the development of viremia. Furthermore, immunization with ChinDENV conferred efficient cross protection against lethal JEV challenge in mice in association with robust cellular immunity induced by the replicating nonstructural proteins. Taken together, the results of this preclinical study well demonstrate the great potential of ChinDENV for further development as a dengue vaccine candidate, and this kind of chimeric flavivirus based on JE vaccine virus represents a powerful tool to deliver foreign antigens.
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Accurate calculation of mutational effects on the thermodynamics of inhibitor binding to p38? MAP kinase: a combined computational and experimental study.
J Chem Theory Comput
PUBLISHED: 08-06-2013
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A major current challenge for drug design efforts focused on protein kinases is the development of drug resistance caused by spontaneous mutations in the kinase catalytic domain. The ubiquity of this problem means that it would be advantageous to develop fast, effective computational methods that could be used to determine the effects of potential resistance-causing mutations before they arise in a clinical setting. With this long-term goal in mind, we have conducted a combined experimental and computational study of the thermodynamic effects of active-site mutations on a well-characterized and high-affinity interaction between a protein kinase and a small-molecule inhibitor. Specifically, we developed a fluorescence-based assay to measure the binding free energy of the small-molecule inhibitor, SB203580, to the p38? MAP kinase and used it measure the inhibitors affinity for five different kinase mutants involving two residues (Val38 and Ala51) that contact the inhibitor in the crystal structure of the inhibitor-kinase complex. We then conducted long, explicit-solvent thermodynamic integration (TI) simulations in an attempt to reproduce the experimental relative binding affinities of the inhibitor for the five mutants; in total, a combined simulation time of 18.5 ?s was obtained. Two widely used force fields - OPLS-AA/L and Amber ff99SB-ILDN - were tested in the TI simulations. Both force fields produced excellent agreement with experiment for three of the five mutants; simulations performed with the OPLS-AA/L force field, however, produced qualitatively incorrect results for the constructs that contained an A51V mutation. Interestingly, the discrepancies with the OPLS-AA/L force field could be rectified by the imposition of position restraints on the atoms of the protein backbone and the inhibitor without destroying the agreement for other mutations; the ability to reproduce experiment depended, however, upon the strength of the restraints force constant. Imposition of position restraints in corresponding simulations that used the Amber ff99SB-ILDN force field had little effect on their ability to match experiment. Overall, the study shows that both force fields can work well for predicting the effects of active-site mutations on small molecule binding affinities and demonstrates how a direct combination of experiment and computation can be a powerful strategy for developing an understanding of protein-inhibitor interactions.
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Virus-like particles produced in Saccharomyces cerevisiae elicit protective immunity against Coxsackievirus A16 in mice.
Appl. Microbiol. Biotechnol.
PUBLISHED: 07-16-2013
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Hand, foot, and mouth disease (HFMD) has caused significant morbidity and mortality in the Asia-Pacific regions, particularly in infants and young children. Coxsackievirus A16 (CA16) represents one of the major causative agents for HFMD, and the development of a safe and effective vaccine preventing CA16 infections has become a public health priority. In this study, we have developed a yeast system for the production of virus-like particles (VLPs) for CA16 by co-expressing P1 and 3CD of CA16 in Saccharomyces cerevisiae. These VLPs exhibit similarity in both protein composition and morphology as empty particles from CA16-infected cells. Immunization with CA16 VLPs in mice potently induced CA16-specific IgG and neutralization antibodies in a dose-dependent manner. IgG subclass isotyping revealed that IgG1 and lgG2b were dominantly induced by VLPs. Meanwhile, cytokine profiling demonstrated that immunization with VLPs significantly induced the secretion of IFN-?, indicating potent cellular immune response. Furthermore, in vivo challenge experiments showed that passive immunization with anti-VLPs sera conferred full protection against lethal CA16 challenge in neonate mice. Taken together, our data demonstrated that VLPs produced in yeast might have the potential to be further developed as a vaccine candidate against HFMD.
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TLR9 signaling repressed tumor suppressor miR-7 expression through up-regulation of HuR in human lung cancer cells.
Cancer Cell Int.
PUBLISHED: 07-12-2013
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Our recent evidence showed that Toll like receptor 9 (TLR9) signaling could enhance the growth and metastatic potential of human lung cancer cells through repressing microRNA-7 (miR-7) expression. Human antigen R (HuR) has been involved in stabilizing multiple mRNAs in cellular biology. However, whether HuR also contributed to the altered expression of miR-7 in TLR9 signaling stimulated human lung cancer cells remains to be elucidated.
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[Clinical observation of transcatheter arterial chemoembolization plus sorafenib in the treatment of advanced hepatocellular carcinoma with different types of portal vein tumor thrombosis].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 06-12-2013
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To explore the efficacy and safety of transcatheter arterial chemoembolization (TACE) plus sorafenib in the treatment of advanced hepatocellular carcinoma with different types of portal vein tumor thrombosis.
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Phenotypic and genomic characterization of human coxsackievirus A16 strains with distinct virulence in mice.
Virus Res.
PUBLISHED: 05-08-2013
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Human coxsackievirus A16 (CA16) infection results in hand, foot, and mouth disease (HFMD) along with other severe neurological diseases in children and poses an important public health threat in Asian countries. During an HFMD epidemic in 2009 in Guangdong, China, two CA16 strains (GD09/119 and GD09/24) were isolated and characterized. Although both strains were similar in plaque morphology and growth properties in vitro, the two isolates exhibited distinct pathogenicity in neonatal mice upon intraperitoneal or intracranial injection. Complete genome sequences of both CA16 strains were determined, and the possible virulence determinants were analyzed and predicted. Phylogenetic analysis revealed that these CA16 isolates from Guangdong belonged to the B1b genotype and were closely related to other recent CA16 strains isolated in mainland China. Similarity and bootscanning analyses of these CA16 strains detected homologous recombination with the EV71 prototype strain BrCr in the non-structural gene regions and the 3-untranslated regions. Together, the phenotypic and genomic characterizations of the two clinical CA16 isolates circulating in China were compared in detail, and the potential amino acid residues responsible for CA16 virulence in mice were predicted. These findings will help explain the evolutionary relationship of the CA16 strains circulating in China, warranting future studies investigating enterovirus virulence.
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Rational design of thermostable vaccines by engineered peptide-induced virus self-biomineralization under physiological conditions.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-15-2013
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The development of vaccines against infectious diseases represents one of the most important contributions to medical science. However, vaccine-preventable diseases still cause millions of deaths each year due to the thermal instability and poor efficacy of vaccines. Using the human enterovirus type 71 vaccine strain as a model, we suggest a combined, rational design approach to improve the thermostability and immunogenicity of live vaccines by self-biomineralization. The biomimetic nucleating peptides are rationally integrated onto the capsid of enterovirus type 71 by reverse genetics so that calcium phosphate mineralization can be biologically induced onto vaccine surfaces under physiological conditions, generating a mineral exterior. This engineered self-biomineralized virus was characterized in detail for its unique structural, virological, and chemical properties. Analogous to many exteriors, the mineral coating confers some new properties on enclosed vaccines. The self-biomineralized vaccine can be stored at 26 °C for more than 9 d and at 37 °C for approximately 1 wk. Both in vitro and in vivo experiments demonstrate that this engineered vaccine can be used efficiently after heat treatment or ambient temperature storage, which reduces the dependence on a cold chain. Such a combination of genetic technology and biomineralization provides an economic solution for current vaccination programs, especially in developing countries that lack expensive refrigeration infrastructures.
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Novel cis-acting element within the capsid-coding region enhances flavivirus viral-RNA replication by regulating genome cyclization.
J. Virol.
PUBLISHED: 04-10-2013
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cis-Acting elements in the viral genome RNA (vRNA) are essential for the translation, replication, and/or encapsidation of RNA viruses. In this study, a novel conserved cis-acting element was identified in the capsid-coding region of mosquito-borne flavivirus. The downstream of 5 cyclization sequence (5CS) pseudoknot (DCS-PK) element has a three-stem pseudoknot structure, as demonstrated by structure prediction and biochemical analysis. Using dengue virus as a model, we show that DCS-PK enhances vRNA replication and that its function depends on its secondary structure and specific primary sequence. Mutagenesis revealed that the highly conserved stem 1 and loop 2, which are involved in potential loop-helix interactions, are crucial for DCS-PK function. A predicted loop 1-stem 3 base triple interaction is important for the structural stability and function of DCS-PK. Moreover, the function of DCS-PK depends on its position relative to the 5CS, and the presence of DCS-PK facilitates the formation of 5-3 RNA complexes. Taken together, our results reveal that the cis-acting element DCS-PK enhances vRNA replication by regulating genome cyclization, and DCS-PK might interplay with other cis-acting elements to form a functional vRNA cyclization domain, thus playing critical roles during the flavivirus life cycle and evolution.
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Identification and characterization of a linearized B-cell epitope on the pr protein of dengue virus.
J. Gen. Virol.
PUBLISHED: 04-04-2013
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The four serotypes of dengue virus (DENV) represent one of the major mosquito-borne pathogens globally; so far no vaccine or specific antiviral is available. During virion maturation, the pr protein is cleaved from its precursor form the prM protein on the surface of immature DENV by host protease. Recent findings have demonstrated that the pr protein not only played critical roles in virion assembly and maturation, but was also involved in antibody-dependent enhancement of DENV infection. However, the B-cell epitopes on the pr protein of DENV have not been well characterized. In this study, a set of 11 partially overlapping peptides spanning the entire pr protein of DENV-2 were fused with glutathione S-transferase and expressed in Escherichia coli. ELISA screening with murine hyperimmune antiserum against immature DENV identified the P8 peptide (??KQNEPEDIDCWCNST?¹) in the pr protein as the major immunodominant epitope. Fine mapping by truncated protein assays confirmed the 8-e peptide ??KQNEPEDI?? was the smallest unit capable of antibody binding. Importantly, the 8-e epitope reacted with sera from dengue fever patients. Site-directed mutagenesis revealed the asparagine residue at position 59 was important for epitope recognition. The 8-e epitope coincided well with the B-cell epitopes predicted by Immune Epitope Database analysis, and 3D structural modelling mapped the 8-e peptide on the surface of prM-E heterodimers. Overall, our findings characterized a linearized B-cell epitope on the pr protein of DENV, which will help to understand the life cycle of DENV and pathogenesis of dengue infections in human.
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Rational design of a flavivirus vaccine by abolishing viral RNA 2-O methylation.
J. Virol.
PUBLISHED: 03-13-2013
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Viruses that replicate in the cytoplasm cannot access the host nuclear capping machinery. These viruses have evolved viral methyltransferase(s) to methylate N-7 and 2-O cap of their RNA; alternatively, they "snatch" host mRNA cap to form the 5 end of viral RNA. The function of 2-O methylation of viral RNA cap is to mimic cellular mRNA and to evade host innate immune restriction. A cytoplasmic virus defective in 2-O methylation is replicative, but its viral RNA lacks 2-O methylation and is recognized and eliminated by the host immune response. Such a mutant virus could be rationally designed as a live attenuated vaccine. Here, we use Japanese encephalitis virus (JEV), an important mosquito-borne flavivirus, to prove this novel vaccine concept. We show that JEV methyltransferase is responsible for both N-7 and 2-O cap methylations as well as evasion of host innate immune response. Recombinant virus completely defective in 2-O methylation was stable in cell culture after being passaged for >30 days. The mutant virus was attenuated in mice, elicited robust humoral and cellular immune responses, and retained the engineered mutation in vivo. A single dose of immunization induced full protection against lethal challenge with JEV strains in mice. Mechanistically, the attenuation phenotype was attributed to the enhanced sensitivity of the mutant virus to the antiviral effects of interferon and IFIT proteins. Collectively, the results demonstrate the feasibility of using 2-O methylation-defective virus as a vaccine approach; this vaccine approach should be applicable to other flaviviruses and nonflaviviruses that encode their own viral 2-O methyltransferases.
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Development and characterization of the replicon system of Japanese encephalitis live vaccine virus SA14-14-2.
Virol. J.
PUBLISHED: 02-22-2013
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Viral self-replicating sub-genomic replicons represent a powerful tool for studying viral genome replication, antiviral screening and chimeric vaccine development. Many kinds of flavivirus replicons have been developed with broad applications.
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Noninvasive bioluminescence imaging of dengue virus infection in the brain of A129 mice.
Appl. Microbiol. Biotechnol.
PUBLISHED: 01-16-2013
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Dengue virus (DENV) infection is one of the most important public health threats globally; however, no vaccines or effective antivirals are currently available. The bioluminescence imaging technique has emerged as a powerful tool for studies on viral pathogenesis in vitro and in vivo. In this study, using a recombinant DENV that stably expressed Renilla luciferase (Rluc-DENV), we used bioluminescence for imaging of DENV infection in the brain of A129 mice that lacked type I interferon receptors. Upon intracranial inoculation with Rluc-DENV, A129 mice developed typical neurological symptoms and rapidly succumbed to viral infection. Real-time bioluminescence intensity analysis revealed the replication kinetics of Rluc-DENV in the brain of A129 mice. Linear regression analyses showed a good correlation between photon flux and viral titers (R(2) = 0.9923). Finally, the bioluminescence model was validated using a known mouse monoclonal antibody, 2A10G6, and the therapeutic effects of this neutralizing antibody were readily monitored by live imaging in the same animal. The noninvasive bioluminescence imaging of DENV infection as described here shows distinct advantages over traditional animal models and provides a powerful tool for potential antiviral or vaccine assays against DENV infection in vivo.
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The role of transarterial embolization in the management of hematuria secondary to congenital renal arteriovenous malformations.
Urol. Int.
PUBLISHED: 01-07-2013
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To evaluate the efficacy and safety of transarterial embolization (TAE) in the management of hematuria secondary to congenital renal arteriovenous malformations (AVM).
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Theoretical studies on the thermodynamic properties, densities, detonation properties, and pyrolysis mechanisms of trinitromethyl-substituted aminotetrazole compounds.
J Mol Model
PUBLISHED: 01-04-2013
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Trinitromethyl-substituted aminotetrazoles with -NH?, -NO?, -N?, and -NHC(NO?)? groups were investigated at the B3LYP/6-31G(d) level of density functional theory. Their sublimation enthalpies, thermodynamic properties, and heats of formation were calculated. The thermodynamic properties of these compounds increase with temperature as well as with the number of nitro groups attached to the tetrazole ring. In addition, the detonation velocities and detonation pressures of these compounds were successfully predicted using the Kamlet-Jacobs equations. It was found that these compounds exhibit good detonation properties, and that compound G (D = 9.2 km/s, P = 38.8 GPa) has the most powerful detonation properties, which are similar to those of the well-known explosive HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocine). Finally, the electronic structures and bond dissociation energies of these compounds were calculated. The BDEs of their C-NO? bonds were found to range from 101.9 to 125.8 kJ/mol(-1). All of these results should provide useful fundamental information for the design of novel HEDMs.
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Global transcriptomic analysis of human neuroblastoma cells in response to enterovirus type 71 infection.
PLoS ONE
PUBLISHED: 01-01-2013
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Human enterovirus type 71 (EV71) is the major pathogen of hand-foot-and-mouth disease (HFMD) and has been associated with severe neurological disease and even death in infants and young children. The pathogenesis of EV71 infection in the human central nervous system remains unclear. In this study, human whole genome microarray was employed to perform transcriptome profiling in SH-SY5Y human neuroblastoma cells infected with EV71. The results indicated that EV71 infection lead to altered expression of 161 human mRNAs, including 74 up-regulated genes and 87 down-regulated genes. Bioinformatics analysis indicated the possible roles of the differentially regulated mRNAs in selected pathways, including cell cycle/proliferation, apoptosis, and cytokine/chemokine responses. Finally, the microarray results were validated using real-time RT-PCR with high identity. Overall, our results provided fundamental information regarding the host response to EV71 infection in human neuroblastoma cells, and this finding will help explain the pathogenesis of EV71 infection and virus-host interaction.
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Human IgG subclasses against enterovirus Type 71: neutralization versus antibody dependent enhancement of infection.
PLoS ONE
PUBLISHED: 01-01-2013
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The emerging human enterovirus 71 (EV71) represents a growing threat to public health, and no vaccine or specific antiviral is currently available. Human intravenous immunoglobulin (IVIG) is clinical used in treating severe EV71 infections. However, the discovery of antibody dependent enhancement (ADE) of EV71 infection illustrates the complex roles of antibody in controlling EV71 infection. In this study, to identify the distinct role of each IgG subclass on neutralization and enhancement of EV71 infection, different lots of pharmaceutical IVIG preparations manufactured from Chinese donors were used for IgG subclass fractionation by pH gradient elution with the protein A-conjugated affinity column. The neutralization and ADE capacities on EV71 infection of each purified IgG subclass were then assayed, respectively. The neutralizing activity of human IVIG is mainly mediated by IgG1 subclass and to less extent by IgG2 subclass. Interestingly, IgG3 fraction did not have neutralizing activity but enhanced EV71 infection in vitro. These results revealed the different roles of human IgG subclasses on EV71 infection, which is of critical importance for the rational design of immunotherapy and vaccines against severe EV71 diseases.
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[The diagnosis and treatment of isolated celiac and superior mesenteric artery dissection: 2 cases report and literature review].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 12-20-2011
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To investigate the diagnosis and treatment of isolated celiac artery (CA) dissection and superior mesenteric artery (SMA) dissection.
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Stanozolol regulates proliferation of growth plate chondrocytes via activation of ERalpha in GnRHa-treated adolescent rats.
J. Pediatr. Endocrinol. Metab.
PUBLISHED: 08-10-2011
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Improving the final adult height is one of the most important aims for treatment of central precocious puberty. Stanozolol (ST) is a synthetic derivative of androgen. In this study, we investigated the effects and the mechanisms of ST on the proliferation of growth plate chondrocytes isolated from adolescent rats treated with gonadotropin-releasing hormone analogue (GnRHa). Treatment with ST resulted in time- and concentration-dependent effects on proliferation as determined by MTT and proliferating cell nuclear antigen (PCNA) assays. Western blotting showed that ST increased the phosphorylation level of the estrogen receptor alpha (ERalpha), but not the androgen receptor (AR). Pharmacological inhibition of ERalpha and mitogen-activated protein kinase (MAPK) attenuated the effects of ST on the proliferation of growth plate chondrocytes. A molecular dynamics simulation showed hydrophobic interactions between ST and ERalpha. These results suggested that ERalpha, but not AR, partially mediates the ST-driven proliferation of growth plate chondrocytes, and that multiple pathways may be involved in the mechanism of action of ST.
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[Labeling of liver cancer cell for fluorescence imaging study by far-red fluorescence protein reporter gene mKate2].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 07-16-2011
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To create far-red fluorescence protein reporter gene mKate2 lentivirus, label human liver cancer cell line HepG2 with lentivirus and explore the feasibility of in vitro fluorescence imaging of labeled tumor cells so as to provide experimental rationales for in vivo fluorescence tumor imaging.
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[Construction and validation of dual fusion reporter gene expression vector for molecular imaging study].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 06-29-2011
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To construct dual fusion reporter gene expression vector containing enhanced green fluorescence protein (EGFP) and human transferrin receptor (TfR), and validate the reconstructed plasmid, which will provide experimental foundation for in vivo dual-modality optical/Magnetic Resonance (MR) imaging.
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Design of chiral sulfoxide-olefins as a new class of sulfur-based olefin ligands for asymmetric catalysis.
Org. Lett.
PUBLISHED: 06-02-2011
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The design and development of a novel class of chiral sulfur-olefin hybrid ligands with high synthetic feasibility are described. These new sulfoxide-olefin ligands showed excellent catalytic activities and enantioselectivities (up to 98% ee) in rhodium-catalyzed asymmetric 1,4-addition reactions of aryl boronic acids to ?,?-unsaturated carbonyl compounds.
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[Investigation of the level of perceived control of asthma and the factors affecting such perception in South China].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 04-26-2011
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To investigate the level of the patients perceived control of asthma (PCA) in South China and analyze the risk factors contributing to inadequate PCA.
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Cisplatin sensitizes human hepatocellular carcinoma cells, but not hepatocytes and mesenchymal stem cells, to TRAIL within a therapeutic window partially depending on the upregulation of DR5.
Oncol. Rep.
PUBLISHED: 08-26-2010
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Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF family of cytokines and has been shown to induce cell apoptosis in many types of tumors, but not in normal cells. This tumor-selective property has made TRAIL a promising approach for the development of cancer therapy. However, hepatocellular carcinoma (HCC) cells display a striking resistance to TRAIL. Although some chemotherapeutic agents can overcome this resistance, safety issues remain a concern because the combination of these agents and TRAIL has been reported to induce toxicity in normal hepatocytes. In this study, we examined whether cisplatin could reverse TRAIL resistance in HCC cells with different p53 status and evaluated the toxicity of combination TRAIL and cisplatin to normal hepatocytes and mesenchymal stem cells (MSCs). We observed that cisplatin could efficiently sensitize HCC cells, but not hepatocytes and MSCs to TRAIL-induced apoptosis within a wide therapeutic window. The apoptosis of HCC cells only partially depended on the upregulation of DR5 and the status of p53. In addition, we provide favorable evidence supporting the feasibility of the combination of chemotherapy and MSCs transduced with TRAIL.
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[Enhanced green fluorescence protein reporter gene labeling of mesenchymal stem cells mediated by lentivirus].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 07-22-2010
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To explore the effect of enhanced green fluorescence protein (EGFP) labeling mediated by lentivirus on the biophysical properties of mesenchymal stem cells (MSC), and whether the EGFP gene expression is permanent and stable.
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[Evaluation of esophageal varices and predicting the risk of esophageal varices bleeding with multi-detector CT in patients with portal hypertension].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-09-2010
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The objective of this study was to evaluate the performance of 320-row multi-detector CT (MDCT) in the detection and grading of esophageal varices and to evaluate the ability of MDCT in predicting the risk of hemorrhage in comparison with upper endoscopy in patients with portal hypertension.
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[Initial application of coronary images from 320-slice dynamic volume MDCT].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-07-2010
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To evaluate initial application of coronary images from 320-slice dynamic volume MDCT (Toshiba Aquilion One dynamic volume MDCT).
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[Magnetic/luminescent quantum dots bifunctional nanoparticles labeling of rat bone mesenchymal stem cells].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-02-2010
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To evaluate the dual-labeling efficiency of magnetic and luminescent quantum dots bifunctional nanoparticles to rat bone mesenchymal stem cells (BMSC).
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Chemoembolization with lobaplatin mixed with iodized oil for unresectable recurrent hepatocellular carcinoma after orthotopic liver transplantation.
J Vasc Interv Radiol
PUBLISHED: 02-08-2010
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To determine whether chemoembolization can benefit patients with unresectable recurrent hepatocellular carcinoma (HCC) after orthotopic liver transplantation (OLT).
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Transvenous embolization of cavernous sinus dural arteriovenous fistulas using detachable coils and Glubran 2 acrylic glue via the inferior petrosal sinus approach.
Eur Radiol
PUBLISHED: 02-02-2010
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To describe the technique, efficacy, and safety of transvenous embolisation (TVE) of cavernous sinus arteriovenous fistulas (CSDAVFs) via the inferior petrosal sinus (IPS) with detachable coils and acrylic glue.
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MR tracking of magnetically labeled mesenchymal stem cells in rats with liver fibrosis.
Magn Reson Imaging
PUBLISHED: 01-21-2010
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In vivo magnetic resonance (MR) tracking of magnetically labeled bone marrow mesenchymal stem cells (BMSCs) administered via the mesenteric vein to rats with liver fibrosis.
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[Stanozolol activates the cross-talk of estrogen receptor alpha-insulin-like growth factor-1 receptor-extracellular-signal regulated kinase 1/2 in the growth plate chondrocytes of estrogen-inhibited adolescent rats in vitro].
Zhonghua Er Ke Za Zhi
PUBLISHED: 12-22-2009
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To investigate the effects and the mechanisms of stanozolol (ST) on the proliferation, maturation and differentiation of in vitro cultured growth plate chondrocyte isolated from gonadotropin releasing hormone analogue (GnRHa)-treated adolescent rats, to study if ST mediates the proliferation of chondrocytes via the estrogen receptor alpha (ERalpha), androgen receptor (AR) and/or insulin-like growth factor-1 receptor (IGF-1R) and interactions of the two receptor and IGF-1R receptor signaling pathway, to investigate the mechanism of the biological effects in ST promoting bone growth/maturity at molecular level.
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[Multimodality interventional treatments for biliary complications after orthotopic liver transplantation: a preliminary study].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 09-30-2009
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To describe the technique, efficacy, and safety of multimodality interventional treatments for biliary complications after orthotopic liver transplantation (OLT). The core of multimodality interventional treatments is percutaneous transhepatic biliary drainage (PTBD).
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Static pressure promotes rat aortic smooth muscle cell proliferation via upregulation of volume-regulated chloride channel.
Cell. Physiol. Biochem.
PUBLISHED: 09-23-2009
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Arterial smooth muscle cell proliferation is a key event in the development of hypertension associated vascular disease. Although previous studies have found that pressure itself can promote cell proliferation and DNA synthesis in vascular smooth muscle cells, the mechanisms are not clear. Recent accumulating evidence indicate that volume-regulated chloride channel plays an important role in the regulation of cell proliferation induced by numerous mitogenic factors. However, whether volume-regulated chloride channel is involved in hypertension-induced vascular smooth muscle cell proliferation remains to be determined. In this study, we found that static pressure promoted rat aortic smooth muscle cell proliferation and cell cycle progression. Static pressure treatment increased volume-regulated chloride currents and ClC-3 expression. Inhibition of chloride channel with pharmacological blockers or knockdown of ClC-3 with ClC-3 antisense transfection attenuated pressure-evoked cell proliferation and cell cycle progression. Static pressure enhanced the production of reactive oxygen species (ROS) in aortic smooth muscle cells. Diphenyleneiodonium (DPI) or apocynin pretreatment inhibited pressure-induced ROS production as well as cell proliferation. Furthermore, DPI or apocynin attenuated the pressure-induced upregulation of ClC-3 protein and hypoosmolarity-activated chloride current. Our data suggest that volume-regulated chloride channel plays a critical role in static pressure-induced cell proliferation and cell cycle progression, suggesting the therapeutic importance of volume-regulated chloride channel for treatment of hypertension attendant vascular complications.
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[Research on SCB discharge behavior with atomic emission spectroscopy].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 07-07-2009
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Semiconductor bridge (SCB) was utilized to ignite energetic materials with thin film discharge and characterized of low input energy, high safety and logic control possibility. SCB discharge was diagnosticated with atomic emission spectroscopy. Firstly, discharge temperature was acquired with copper atom spectral lines 510.5 and 521.8 nm, and electron density was calculated with silicon atom spectral line 390.5 nm and corresponding ion line 413.0 nm. As for resistance 1.0 omega of SCB with the discharge voltage of 20 V and capacity of 47 microF, its discharge temperature was about 2 500-4 300 K and electron density 10(16) cm(-3). Meanwhile, the temperature and density V(s) time distributions were acquired simultaneously. And then with the diagnosis results, the discharge behaviors of two sorts of SCB were judged according to plasma space-dimension and time-dimension restrictions. This research set up an efficient technique for the diagnosis of transient small-size discharge behavior and provided instructions for the design of SCB and discharge condition.
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[The role of early hepatic artery ischemia on biliary complications after liver transplantation and hepatic arterial interventional therapy].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 06-25-2009
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To explore the influence of early hepatic artery ischemia on the occurrence and prognosis of biliary complications after orthotopic liver transplantation (OLT), and the value of early hepatic arterial interventional therapy.
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Selection of the most powerful predictors for the evaluation of hepatic steatosis grade: an experimental study.
Eur J Radiol
PUBLISHED: 05-06-2009
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To select the most powerful predictors for the evaluation of hepatic steatosis grade.
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Expression and purification of bioactive high-purity human midkine in Escherichia coli.
J Zhejiang Univ Sci B
PUBLISHED: 02-24-2009
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Midkine is a heparin-binding growth factor, which plays important roles in the regulation of cell growth and differentiation. The non-tagged recombinant human midkine (rhMK) is therefore required to facilitate its functional studies of this important growth factor. In the present work, rhMK was expressed in Escherichia coli (E. coli) BL21 (DE3). The expression of midkine was efficiently induced by isopropyl-beta-D-thiogalactopyranoside (IPTG). After sonication, midkine was recovered in an insoluble form, and was dissolved in guanidine hydrochloride buffer. Renaturation of the denatured protein was carried out in the defined protein refolding buffer, and the refolded protein was purified using S-Sepharose ion-exchange chromatography. The final preparation of the rhMK was greater than 98% pure as measured by sodium dodecylsulfate-polyacrylamid gel electrophoresis (SDS-PAGE) and reverse phase high performance liquid chromatography (RP-HPLC). The purified rhMK enhanced the proliferation of NIH3T3 cells.
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Influence of environmental manipulation on exploratory behaviour in male BDNF knockout mice.
Behav. Brain Res.
PUBLISHED: 02-24-2009
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It is widely accepted that brain derived neurotrophic factor (BDNF) plays a crucial role in mediating changes in learning and memory performance induced by environmental conditions. In order to ascertain whether BDNF modulates environmentally induced changes in exploratory behaviour, we examined mice carrying a deletion in one copy of the BDNF gene. Young heterozygous male BDNF knockout mice (BDNF+/-) and their wild-type (WT) controls were exposed to the enriched environment condition (EC) or the standard condition (SC) for 8 weeks. Exploratory behaviour was assessed in the open-field (OF) and hole-board (HB) test. Brains from EC and SC reared animals were processed for Golgi-Cox staining and the dendritic spine density in the dentate gyrus (DG) and CA1 hippocampal regions were examined. We found behavioural differences both due to the genetic modification and the environmental manipulation, with the BDNF+/- mice being more active in the OF whereas the EC mice had increased exploratory behaviour in the HB test. Environmental enrichment also led to an increase in dendritic spines in the hippocampal CA1 region and DG of the wild-type mice. This effect was also found in the enriched BDNF+/- mice, but was less pronounced. Our findings support the critical role of BDNF in behavioural and neural plasticity associated with environmental enrichment and suggest that besides maze learning performance, BDNF dependent mechanisms are also involved in other aspects of behaviour. Here we provide additional evidence that exploratory activity is influenced by BDNF.
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Inhibitive effect of artemether on tumor growth and angiogenesis in the rat C6 orthotopic brain gliomas model.
Integr Cancer Ther
PUBLISHED: 01-27-2009
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To explore the inhibitive effect of artemether on glioma growth and angiogenesis in brain tumor bearing SD rat. MTT assay was used to evaluate the inhibitory effect of artemether treatment on C6 glioma cells. Forty SD rats which were subcutaneous planted with SD rat C6 glioma cell to establish SD rat orthotopic glioma model were divided resourcefully into 5 groups. each group was 8 rats. Length-path (a mm) and short-path (b mm) of tumor each rat was measured. Tumor volume was calculated using the following formula: V (mm(3)) = a(2)bpi/6. Microvessel density (MVD) in different therapy groups was significantly lower than that in normal saline control group and brain glioma volume in different therapy groups was significantly smaller than that in normal saline control group. There were remarkably inhibitory effects of artmeter on brain glioma growth and angiogenesis in SD rats and the mechanism that artemether inhibited brain glioma growth might be penetrating the blood-brain barrier and inhibiting angiogenesis.
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Different methods of detaching adherent cells significantly affect the detection of TRAIL receptors.
Tumori
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As a powerful technique allowing analysis of large numbers of cells, fluorescence-activated cell sorting (FACS) is used more and more widely. For FACS analysis, adherent cells are usually detached by trypsinization, followed by centrifugation and resuspension. However, trypsinization can cut off some receptors from the cell surface like fine scissors, which will affect the accuracy of FACS results. Though non-enzymatic methods such as citric saline buffer have been used to determine cell surface receptors, how much of the receptors is cut off by trypsinization has been rarely studied. This work aimed to investigate whether different methods of detaching adherent cells could affect the detection of cell surface receptors.
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Rhodium-catalyzed enantioselective addition to unsymmetrical ?-diketones: tandem one-pot synthesis of optically active 3-tetrasubstituted isochroman derivatives.
Chemistry
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The domino effect: An efficient and general catalytic one-pot synthesis of quaternary-substituted isochroman derivatives has been developed (see scheme). The cascade transformation relies on rhodium-catalyzed highly regio- and enantioselective 1,2-addition of arylboronic acids to unsymmetrical ?-diketones and intramolecular etherification or esterification, and provides a variety of enantioenriched isochromanones under exceptionally mild conditions.
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Uterine artery embolization combined with methotrexate in the treatment of cesarean scar pregnancy: results of a case series and review of the literature.
J Vasc Interv Radiol
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To explore the clinical value of uterine artery embolization (UAE) combined with methotrexate in the treatment of cesarean scar pregnancy (CSP) before and after uterine curettage.
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Complete genome sequence analysis of human echovirus type 30 isolated in China.
J. Virol.
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We report here the complete genome sequence of a human echovirus type 30 strain ECV30/GX10/05 isolated in Guangxi, China, in 2010. Phylogenetic analysis showed that ECV30/GX10/05 was closely related to a Korean strain isolated in 2008. The sequence information will help in an understanding of the molecular epidemiology and evolution of echovirus.
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Complete genome sequence of dengue virus serotype 2 Cosmopolitan genotype strain in Guangdong, China.
J. Virol.
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Here we report the complete genome sequence of a dengue virus serotype 2 (DENV-2) strain, GZ40, isolated in Guangdong, China, in 2010. A phylogenetic analysis classified GZ40 into the Cosmopolitan genotype, while previous Chinese DENV-2 isolates belong to the Asian I genotype. The reemergence of the Cosmopolitan genotype of DENV-2 in China deserves further investigation.
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[Evaluation of graft perfusion in patients with ischemic-type of biliary lesions after liver transplantation].
Zhonghua Yi Xue Za Zhi
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To investigate the value of 320-rows CT perfusion (CTP) imaging in the study of hepatic hemodynamic characters in ischemic-type biliary lesions (ITBL) after liver transplantation.
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Theoretical investigation of a novel high density cage compound 4,8,11,14,15-pentanitro-2,6,9,13-tetraoxa-4,8,11,14,15-pentaazaheptacyclo[5.5.1.1(3,11).1(5,9)] pentadecane.
J Mol Model
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A novel polynitro cage compound 4,8,11,14,15-pentanitro-2,6,9,13-tetraoxa-4,8,11,14,15-pentaazaheptacyclo [5.5.1.1(3,11).1(5,9)]pentadecane(PNTOPAHP) has been designed and investigated at the DFT-B3LYP/6-31(d) level. Properties, such as electronic structure, IR spectrum, heat of formation, thermodynamic properties and crystal structure have been predicted. This compound is most likely to crystallize in C2/c space group, and the corresponding cell parameters are Z = 8, a = 29.78 Å, b = 6.42 Å, c = 32.69 Å, ? = 90.00°, ? = 151.05°, ? = 90.00° and ? = 1.94 g/cm(3). In addition, the detonation velocity and pressure have also been calculated by the empirical Kamlet-Jacobs equation. As a result, the detonation velocity and pressure of this compound are 9.82 km/s, 44.67 GPa, respectively, a little higher than those of 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowurtzitane(TEX, 9.28 km/s, 40.72 GPa). This compound has a comparable chemical stability to TEX, based on the N-NO(2) trigger bond length analysis. The bond dissociation energy ranges from 153.09 kJ mol(-1) to 186.04 kJ mol(-1), which indicates that this compound meets the thermal stability requirement as an exploitable HEDM.
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Rhodium-catalyzed enantioselective 1,2-addition of arylboronic acids to heteroaryl ?-ketoesters for synthesis of heteroaromatic ?-hydroxy esters.
Org. Biomol. Chem.
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The first example of catalytic asymmetric 1,2-addition of arylboronic acids to heteroaryl ?-ketoesters has been developed for the highly efficient and enantioselective synthesis of quaternary carbon-containing heteroaromatic ?-hydroxy esters. The reaction works well with a variety of ?-ketoesters including 3-indoleglyoxylates, 3-benzofuranglyoxylates and 3-benzothiopheneglyoxylates under very mild conditions, affording the corresponding products in moderate to good yields with high enantiomeric excesses (up to 97%).
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[Effects of breast cancer cells stably overexpressing RSK4 on growth of transplanted human breast cancer in severe combined immunodeficiency mice].
Zhonghua Yi Xue Za Zhi
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To construct a breast cancer cell line MD-MB-231 stably overexpressing RSK4 gene and study its in vivo effects on tumor tumorigenesis.
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[Diagnosis and treatment of carotid-cavernous fistula: analysis of 28 patients].
Zhonghua Yi Xue Za Zhi
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To evaluate the feasibility and efficacy of endovascular treatment for different types of carotid cavernous fistula (CCF) via the approach of internal carotid artery (ICA) or inferior petrosal sinus (IPS).
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The inhibitory effect of MSCs expressing TRAIL as a cellular delivery vehicle in combination with cisplatin on hepatocellular carcinoma.
Cancer Biol. Ther.
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Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been demonstrated to induce cell apoptosis in many types of tumors, while many hepatocellular carcinoma (HCC) cells display high resistance to TRAIL. Another outstanding limitation of TRAIL is the short half-life in vivo. Stem cell-based therapies provide a promising approach for the treatment of many types of tumors because of the ability of tropism. Therefore, as a new therapeutic strategy, the combination of chemotherapeutic agents and TRAIL gene modified MSCs (TRAIL-MSCs) would improve the therapeutic efficacy of HCC in vivo. This is the first time to show the potential of combination of chemotherapeutic agents and MSCs as a gene vector in the therapy of HCC.
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Development of RT-LAMP and real-time RT-PCR assays for the rapid detection of the new duck Tembusu-like BYD virus.
Arch. Virol.
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A new duck Tembusu virus (TMUV), also known as BYD virus, has been identified as the causative agent for the emerging duck egg-drop syndrome in mainland China. The rapid spread and wide distribution of the new TMUV in mainland China result in heavy loss to the poultry industry and pose great threats to public health. Rapid and sensitive detection methods are critical for prevention and control of TMUV infections. In this study, a reverse-transcription loop-mediated isothermal amplification assay (RT-LAMP) and an SYBR Green-I-based real-time RT-PCR assay specific for the duck TMUV were developed and validated with laboratory and field samples, respectively. The detection limits were 1 × 10(-4) and 1 × 10(-3) PFU per reaction for the RT-LAMP assay and real-time RT-PCR assay, respectively. The specificities were analyzed with other related members of the genus Flavivirus, and no cross-reaction was observed. Furthermore, both assays were evaluated with field samples, and they exhibited high sensitivity and specificity. In addition, the real-time RT-PCR assay worked well in viral load analysis, which revealed that the spleen may be the primary target for the replication of new duck TMUV in ducks. The TMUV-specific RT-LAMP and real-time RT-PCR assays will provide useful tools for the diagnosis and epidemiological surveillance of TMUV infection.
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Complete genome sequence of a chikungunya virus isolated in Guangdong, China.
J. Virol.
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Chikungunya virus belongs to the genus Alphavirus in the family Togaviridae. Here we report the complete genome sequence of a chikungunya virus strain, GD05/2010, isolated in 2010 from a patient with chikungunya fever in Guangdong, China. The sequence information is important for surveillance of this emerging arboviral infection in China.
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[Post-therapeutic change of cathelicidin LL-37 in asthmatics of different inflammatory phenotypes].
Zhonghua Yi Xue Za Zhi
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To explore the post-therapeutic change of cathelicidin LL-37 in asthmatics of different inflammatory phenotypes.
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What is Visualize?

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

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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.