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Find video protocols related to scientific articles indexed in Pubmed.
Discovery of Pentacyclic Triterpenoids as Potential Entry Inhibitors of Influenza Viruses.
J. Med. Chem.
PUBLISHED: 11-11-2014
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Entry inhibitors are of particular importance in current efforts to develop a new generation of anti-influenza virus drugs. Here we report certain pentacyclic triterpenes exhibiting conserved structure features and with in vitro anti-influenza virus activity comparable to and even higher than that of oseltamivir. Mechanistic studies indicated that these lead triterpenoids bind tightly to the viral envelope hemagglutinin (HA), disrupting the interaction of HA with the sialic acid receptor and thus the attachment of viruses to host cells. Docking studies suggest that the binding pocket within HA for sialic acid receptor potentially acts as a targeting domain, and this is supported by structure-activity data, sialic acid competition studies and broad anti-influenza spectrum as well as less induction of drug resistance. Our study might establish the importance of triterpenoids for development of entry inhibitors of influenza viruses.
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Effect of vaginal immunization with HIVgp140 and HSP70 on HIV-1 replication and innate and T cell adaptive immunity in women.
J. Virol.
PUBLISHED: 07-09-2014
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The international effort to prevent HIV-1 infection by vaccination has failed to develop an effective vaccine. The aim of this vaccine trial in women was to administer by the vaginal mucosal route a vaccine consisting of HIV-1 gp140 linked to the chaperone 70-kDa heat shock protein (HSP70). The primary objective was to determine the safety of the vaccine. The secondary objective was to examine HIV-1 infectivity ex vivo and innate and adaptive immunity to HIV-1. Protocol-defined female volunteers were recruited. HIV-1 CN54gp140 linked to HSP70 was administered by the vaginal route. Significant adverse reactions were not detected. HIV-1 was significantly inhibited ex vivo in postimmunization CD4(+) T cells compared with preimmunization CD4(+) T cells. The innate antiviral restrictive factor APOBEC3G was significantly upregulated, as were CC chemokines which induce downregulation of CCR5 in CD4(+) T cells. Indeed, a significant inverse correlation between the proportion of CCR5(+) T cells and the concentration of CCL-3 or CCL-5 was found. Importantly, the upregulation of APOBEC3G showed a significant inverse correlation, whereas CCR5 exhibited a trend to correlate with inhibition of HIV-1 infection (r = 0.51). Furthermore, specific CD4(+) and CD8(+) T cell proliferative responses were significantly increased and CD4(+) T cells showed a trend to have an inverse correlation with the viral load (r = -0.60). However, HIVgp140-specific IgG or IgA antibodies were not detected. The results provide proof of concept that an innate mechanism consisting of CC chemokines, APOBEC3G, and adaptive immunity by CD4 and CD8 T cells might be involved in controlling HIV-1 infectivity following vaginal mucosal immunization in women. (This study has been registered at ClinicalTrials.gov under registration no. NCT01285141.) Importance: Vaginal immunization of women with a vaccine consisting of HIVgp140 linked to the 70-kDa heat shock protein (HSP70) elicited ex vivo significant inhibition of HIV-1 replication in postimmunization CD4(+) T cells compared with that in preimmunization peripheral blood mononuclear cells. There were no significant adverse events. The vaccine induced the significant upregulation of CC chemokines and the downmodulation of CCR5 expression in CD4(+) T cells, as well as an inverse correlation between them. Furthermore, the level of CCR5 expression was directly correlated with the viral load, consistent with the protective mechanism in which a decrease in CCR5 molecules on CD4(+) T cells decreases HIV-1 envelope binding. Expression of the antiviral restriction factor APOBEC3G was inversely correlated with the viral load, suggesting that it may inhibit intracellular HIV-1 replication. Both CD4(+) and CD8(+) T cells showed HIVgp140- and HSP70-specific proliferation. A strong inverse correlation between the proportion of CC chemokine-modulated CCR5-expressing CD4(+) T cells and the stimulation of CD4(+) or CD8(+) T cell proliferation by HIVgp140 was found, demonstrating a significant interaction between innate and adaptive immunity. This is the first clinical trial of vaginal immunization in women using only HIVgp140 and HSP70 administered by the mucosal route (3 times) in which a dual innate protective mechanism was induced and enhanced by significant adaptive CD4(+) and CD8(+) T cell proliferative responses.
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Optimization of self-directed target coverage in wireless multimedia sensor network.
ScientificWorldJournal
PUBLISHED: 06-30-2014
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Video and image sensors in wireless multimedia sensor networks (WMSNs) have directed view and limited sensing angle. So the methods to solve target coverage problem for traditional sensor networks, which use circle sensing model, are not suitable for WMSNs. Based on the FoV (field of view) sensing model and FoV disk model proposed, how expected multimedia sensor covers the target is defined by the deflection angle between target and the sensor's current orientation and the distance between target and the sensor. Then target coverage optimization algorithms based on expected coverage value are presented for single-sensor single-target, multisensor single-target, and single-sensor multitargets problems distinguishingly. Selecting the orientation that sensor rotated to cover every target falling in the FoV disk of that sensor for candidate orientations and using genetic algorithm to multisensor multitargets problem, which has NP-complete complexity, then result in the approximated minimum subset of sensors which covers all the targets in networks. Simulation results show the algorithm's performance and the effect of number of targets on the resulting subset.
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High-brightness single-mode double-tapered laser diodes with laterally coupled high-order surface grating.
Opt Lett
PUBLISHED: 05-31-2014
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Double-tapered laser diodes with 23rd order laterally coupled surface gratings are fabricated at 913 nm. A narrow ridge waveguide restricts the lateral mode number, and tapered waveguides are utilized to enhance the output power. The gratings defined on the sides of ridge waveguide filter not only the longitudinal modes but also the high-order lateral modes. Experimentally, continuous wave power of over 560??mW/facet is achieved. The lateral far-field pattern exhibits a single-lobe profile and narrow divergence, and the lowest divergence angle is only twice the diffraction-limited one. The measured side-mode suppression ratio is about 27 dB. This device has great potential for high-power single-mode near-diffraction-limited laser emission with easy fabrication.
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Rare variants of large effect in BRCA2 and CHEK2 affect risk of lung cancer.
Nat. Genet.
PUBLISHED: 05-08-2014
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We conducted imputation to the 1000 Genomes Project of four genome-wide association studies of lung cancer in populations of European ancestry (11,348 cases and 15,861 controls) and genotyped an additional 10,246 cases and 38,295 controls for follow-up. We identified large-effect genome-wide associations for squamous lung cancer with the rare variants BRCA2 p.Lys3326X (rs11571833, odds ratio (OR) = 2.47, P = 4.74 × 10(-20)) and CHEK2 p.Ile157Thr (rs17879961, OR = 0.38, P = 1.27 × 10(-13)). We also showed an association between common variation at 3q28 (TP63, rs13314271, OR = 1.13, P = 7.22 × 10(-10)) and lung adenocarcinoma that had been previously reported only in Asians. These findings provide further evidence for inherited genetic susceptibility to lung cancer and its biological basis. Additionally, our analysis demonstrates that imputation can identify rare disease-causing variants with substantive effects on cancer risk from preexisting genome-wide association study data.
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Identification of susceptibility loci for colorectal cancer in a genome-wide meta-analysis.
Hum. Mol. Genet.
PUBLISHED: 04-15-2014
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To identify common variants influencing colorectal cancer (CRC) risk, we performed a meta-analysis of five genome-wide association studies, comprising 5626 cases and 7817 controls of European descent. We conducted replication of top ranked single nucleotide polymorphisms (SNPs) in additional series totalling 14 037 cases and 15 937 controls, identifying a new CRC risk locus at 10q24.2 [rs1035209; odds ratio (OR) = 1.13, P = 4.54 × 10(-11)]. We also performed meta-analysis of our studies, with previously published data, of several recently purported CRC risk loci. We failed to find convincing evidence for a previously reported genome-wide association at rs11903757 (2q32.3). Of the three additional loci for which evidence of an association in Europeans has been previously described we failed to show an association between rs59336 (12q24.21) and CRC risk. However, for the other two SNPs, our analyses demonstrated new, formally significant associations with CRC. These are rs3217810 intronic in CCND2 (12p13.32; OR = 1.19, P = 2.16 × 10(-10)) and rs10911251 near LAMC1 (1q25.3; OR = 1.09, P = 1.75 × 10(-8)). Additionally, we found some evidence to support a relationship between, rs647161, rs2423297 and rs10774214 and CRC risk originally identified in East Asians in our European datasets. Our findings provide further insights into the genetic and biological basis of inherited genetic susceptibility to CRC.
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Germline polymorphisms and survival of lung adenocarcinoma patients: A genome-wide study in two European patient series.
Int. J. Cancer
PUBLISHED: 02-28-2014
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In lung cancer, the survival of patients with the same clinical stage varies widely for unknown reasons. In this two-phase study, we examined the hypothesis that germline variations influence the survival of patients with lung adenocarcinoma. First, we analyzed existing genotype and clinical data from 289 UK-resident patients with lung adenocarcinoma, identifying 86 single nucleotide polymorphisms (SNPs) that associated with survival (p?
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Mechanically robust, electrically conductive and stimuli-responsive binary network hydrogels enabled by superelastic graphene aerogels.
Adv. Mater. Weinheim
PUBLISHED: 01-13-2014
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The architecture of the nanofiller phase in polymer nanocomposites matters! Polymer hydrogels that can combine stimuli-responsiveness with excellent electrically conductivity and mechanical strength can be fabricated by incorporation of the polymer into an ultralight and superelastic graphene aerogel to form a binary network.
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Changes of predominant species/biovars and sequence types of Brucella isolates, Inner Mongolia, China.
BMC Infect. Dis.
PUBLISHED: 10-28-2013
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Human brucellosis incidence in China was divided into 3 stages, high incidence (1950-1960s), decline (1970-1980s) and re-emergence (1990-2000s). Human brucellosis has been reported in all the 32 provinces, of which Inner Mongolia has the highest prevalence, accounting for over 40% of the cases in China. To investigate the etiology alteration of human brucellosis in Inner Mongolia, the species, biovars and genotypes of 60 Brucella isolates from this province were analyzed.
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A genome-wide association study identifies multiple susceptibility loci for chronic lymphocytic leukemia.
Nat. Genet.
PUBLISHED: 08-20-2013
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Genome-wide association studies (GWAS) of chronic lymphocytic leukemia (CLL) have shown that common genetic variation contributes to the heritable risk of CLL. To identify additional CLL susceptibility loci, we conducted a GWAS and performed a meta-analysis with a published GWAS totaling 1,739 individuals with CLL (cases) and 5,199 controls with validation in an additional 1,144 cases and 3,151 controls. A combined analysis identified new susceptibility loci mapping to 3q26.2 (rs10936599, P = 1.74 × 10(-9)), 4q26 (rs6858698, P = 3.07 × 10(-9)), 6q25.2 (IPCEF1, rs2236256, P = 1.50 × 10(-10)) and 7q31.33 (POT1, rs17246404, P = 3.40 × 10(-8)). Additionally, we identified a promising association at 5p15.33 (CLPTM1L, rs31490, P = 1.72 × 10(-7)) and validated recently reported putative associations at 5p15.33 (TERT, rs10069690, P = 1.12 × 10(-10)) and 8q22.3 (rs2511714, P = 2.90 × 10(-9)). These findings provide further insights into the genetic and biological basis of inherited genetic susceptibility to CLL.
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Liquid-mediated dense integration of graphene materials for compact capacitive energy storage.
Science
PUBLISHED: 08-03-2013
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Porous yet densely packed carbon electrodes with high ion-accessible surface area and low ion transport resistance are crucial to the realization of high-density electrochemical capacitive energy storage but have proved to be very challenging to produce. Taking advantage of chemically converted graphenes intrinsic microcorrugated two-dimensional configuration and self-assembly behavior, we show that such materials can be readily formed by capillary compression of adaptive graphene gel films in the presence of a nonvolatile liquid electrolyte. This simple soft approach enables subnanometer scale integration of graphene sheets with electrolytes to form highly compact carbon electrodes with a continuous ion transport network. Electrochemical capacitors based on the resulting films can obtain volumetric energy densities approaching 60 watt-hours per liter.
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Deciphering the genetic architecture of low-penetrance susceptibility to colorectal cancer.
Hum. Mol. Genet.
PUBLISHED: 07-30-2013
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Recent genome-wide association studies (GWASs) have identified common variants at 16 autosomal regions influencing the risk of developing colorectal cancer (CRC). To decipher the genetic basis of the association signals at these loci, we performed a meta-analysis of data from five GWASs, totalling 5626 cases and 7817 controls, using imputation to recover un-typed genotypes. To enhance our ability to discover low-frequency risk variants, in addition to using 1000 Genomes Project data as a reference panel, we made use of high-coverage sequencing data on 253 individuals, 199 with early-onset familial CRC. For 13 of the regions, it was possible to refine the association signal identifying a smaller region of interest likely to harbour the functional variant. Our analysis did not provide evidence that any of the associations at the 16 loci being a consequence of synthetic associations rather than linkage disequilibrium with a common risk variant.
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Sensitive and rapid detection of blaNDM-1 in clinical samples by isothermal cross-priming amplification.
J. Microbiol. Methods
PUBLISHED: 06-28-2013
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A highly sensitive, specific diagnostic assay for detection of bla(NDM-1) based on cross priming amplification (CPA) was developed. The sensitivity ranged from 2.5 to 25 copies per reaction for different clinical samples. The highly and sensitive detection of bla(NDM-1) in clinical samples highlighted the potential clinical applications of CPA.
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Formation of regular stripes of chemically converted graphene on hydrophilic substrates.
ACS Appl Mater Interfaces
PUBLISHED: 06-24-2013
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Chemically converted graphene (CCG), from a chemistry point of view, is a giant molecule with a unique two-dimensional (2D) configuration. The availability of CCG dispersion provides a range of scalable methods to assemble graphene-based materials but brings the challenge of understanding and control of the CCG morphology in solution processing. In this study, we found that, similar to conventional colloidal systems (e.g., spherical particles or polymers), a 2D sheet of CCG can be transferred from its aqueous dispersion to solid substrates in the form of highly regular stripe patterns by evaporation-driven deposition. The width and spacing can be defined by the concentration of the CCG dispersion and the properties of the substrate (e.g., roughness and surface charge). Furthermore, the high resolution AFM images illustrate that both 2D flattened and highly wrinkled CCG can be formed in each individual stripe, depending on the location across the stripe. The in situ optical observation of the stripe formation indicates that the morphological change of CCG may occur in the crowded meniscus of the drying front.
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Controlling the assembly of graphene oxide by an electrolyte-assisted approach.
Nanoscale
PUBLISHED: 06-06-2013
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In this work, we studied the effects of salts on the self-assembly of two-dimensional graphene oxide (GO) driven by the dissolution of a sub-microliter droplet. Two kinds of structures were obtained. One was a GO snowball with small salt crystals inserted between sheets, which formed with a low initial concentration of insoluble salt in the GO dispersion. The other was a hybrid nanostructure containing NaCl or KCl crystals on a GO snowball, which formed with a high initial salt concentration in the suspension. In addition, we report the novel nanodent-decorated GO snowballs formed by templating the spontaneously formed microdroplets through ouzo effects. Such highly crumpled snowball structures may find applications in super-capacitors or catalyst supports.
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Lateral cavity photonic crystal surface emitting laser based on commercial epitaxial wafer.
Opt Express
PUBLISHED: 04-11-2013
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A lateral cavity photonic crystal surface emitting laser (LC-PCSEL) with airholes of cone-like shape etched near to the active layer is fabricated. It employs only a simple commercial epitaxial wafer without DBR and needs no wafer bonding technique. Surface emitting lasing action at 1575 nm with power of 1.8 mW is observed at room temperature, providing potential values for mass production of electrically driven PCSELs with low cost. Additionally, Fano resonance is utilized to analyze aperture equivalence of PC, and energy distribution in simplified laser structure is simulated to show oscillation and transmission characteristics of laser.
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Brucella virulence mechanisms and implications in novel vaccines and drugs.
Crit. Rev. Eukaryot. Gene Expr.
PUBLISHED: 04-06-2013
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Brucellosis, an infection caused by Brucella spp., is a common zoonosis in many parts of world. Human chronic infection is successfully established through contact with infected animals or their dirty products. The capacity of establishing and maintaining this persistent infection in the phagosomal compartment of host macro-phages is critical to their ability to produce chronic infections in their mammalian hosts. Bacterial virulence mechanisms play an important role in regulating during the infectious process, both to optimize the functioning of the virulence factors in promoting survival and thwarting host defenses and to produce an effective immune response against these virulence components. The availability of the genomic sequences and molecular strategies such as gene mutant technique provide an opportunity to identify the virulence mechanisms of Brucella. It will greatly accelerate our understanding of the infection of this pathogen and give us more clues to exploit new vaccines and drugs.
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Simultaneous determination of amino acids in tea leaves by micellar electrokinetic chromatography with laser-induced fluorescence detection.
Food Chem
PUBLISHED: 03-11-2013
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A rapid and effective method of micellar electrokinetic chromatography with laser-induced fluorescence detection was developed for the simultaneous determination of amino acids in tea leaves. Pre-column derivatization of the analytes used 4-chloro-7-nitrobenzofurazan (NDB-Cl). Optimal separation was achieved at +20kV using an uncoated fused silica capillary (40.0cm effective length, 50.2cm total length, 75?m internal diameter), as well as 20mM sodium borate (pH 8.5), 20mM Brij 35, and acetonitrile 10% (v/v) as running buffers. Within 11min, 15 amino acids were separated completely. The optimized method demonstrated good linearity (r(2)?0.9990), precision (?6.65%), accuracy (85.50-112.74%), and sensitivity (0.1ng/mL-100ng/mL). The method successfully determined the quantity of amino acids in five different tea leaves; furthermore, theanine was identified as the most abundant amino acid in teas. The proposed method showed great potential in further investigations on the biofunctions of different tea samples.
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Human brucellosis in the Peoples Republic of China during 2005-2010.
Int. J. Infect. Dis.
PUBLISHED: 02-23-2013
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Brucellosis is a worldwide re-emerging zoonotic disease. It remains a serious public health problem in many developing countries including China. This review summarizes the epidemiological characteristics, morbidity, and endemic distributions of human brucellosis in the Peoples Republic of China for the period 2005-2010. From 2005 to 2010, the incidence of human brucellosis rose substantially in China, especially in the provinces of Inner Mongolia, Shanxi3, Heilongjiang, Hebei, Jilin, and Shanxi1. Meanwhile human brucellosis increased gradually in some southern provinces, such as Henan, Guangdong, and Fujian. Due to the rapid expansion of human brucellosis in China, surveillance and prevention of this disease has been greatly challenged.
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Selective catalytic oxidation of H?S over iron oxide supported on alumina-intercalated Laponite clay catalysts.
J. Hazard. Mater.
PUBLISHED: 02-14-2013
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A series of iron oxide supported on alumina-intercalated clay catalysts (named Fe/Al-Lap catalysts) with mesoporous structure and high specific surface area were prepared. The structural and chemical properties were studied by nitrogen sorption isotherms, X-ray diffraction (XRD), UV-vis diffuse reflectance spectra (UV-vis DRS), X-ray photoelectron spectra (XPS), Fourier transform infrared spectroscopy (FTIR), H? temperature-programmed reduction (H?-TPR) and NH? temperature-programmed desorption (NH3-TPD) techniques. It was realized that iron oxide mainly existed in the form of isolated Fe(3+) in an oxidic environment. Fe/Al-Lap catalysts showed high catalytic activities in the temperature range of 120-200 °C without the presence of excessive O?. This can be attributed to the interaction between iron oxide and alumina, which improve the redox property of Fe(3+) efficiently. In addition, the strong acidity of catalysts and good dispersion of iron oxide were also beneficial to oxidation reaction. Among them, 7% Fe/Al-Lap catalyst presented the best catalytic performance at 180 °C. Finally, the catalytic and deactivation mechanisms were explored.
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Deciphering the 8q24.21 association for glioma.
Hum. Mol. Genet.
PUBLISHED: 02-11-2013
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We have previously identified tagSNPs at 8q24.21 influencing glioma risk. We have sought to fine-map the location of the functional basis of this association using data from four genome-wide association studies, comprising a total of 4147 glioma cases and 7435 controls. To improve marker density across the 700 kb region, we imputed genotypes using 1000 Genomes Project data and high-coverage sequencing data generated on 253 individuals. Analysis revealed an imputed low-frequency SNP rs55705857 (P = 2.24 × 10(-38)) which was sufficient to fully capture the 8q24.21 association. Analysis by glioma subtype showed the association with rs55705857 confined to non-glioblastoma multiforme (non-GBM) tumours (P = 1.07 × 10(-67)). Validation of the non-GBM association was shown in three additional datasets (625 non-GBM cases, 2412 controls; P = 1.41 × 10(-28)). In the pooled analysis, the odds ratio for low-grade glioma associated with rs55705857 was 4.3 (P = 2.31 × 10(-94)). rs55705857 maps to a highly evolutionarily conserved sequence within the long non-coding RNA CCDC26 raising the possibility of direct functionality. These data provide additional insights into the aetiological basis of glioma development.
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Dynamic electrosorption analysis as an effective means to characterise the structure of bulk graphene assemblies.
Chemistry
PUBLISHED: 01-10-2013
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Restacking of graphene sheets to a graphite-like structure is a prevailing problem that is known to compromise the performance of individual graphene sheets in an assembled bulk form. To address this common problem efficiently and monitor the structure and quality of graphene products comprehensively, it is highly desirable to develop reliable metrology techniques for characterising graphene-based materials on a bulk assembly level and in a quantitative manner. Here, by revisiting the physicochemical principle of electrosorption, we propose a simple electrochemical approach, namely dynamic electrosorption analysis (DEA), as an easily accessible and effective technique for evaluation of the self-stacking behaviour of graphene. Taking multilayered chemically converted graphene films as a model, we demonstrate that the DEA technique can effectively reveal very subtle variation in accessible surface area and pore size of graphene assemblies in the liquid phase and thus can provide useful insights to the experimental design relating to restacking control. This work also reveals the huge effect some routine processing conditions, such as heat treatment and drying, can have on the structure and performance of graphene-based bulk materials, providing useful guidance for future manufacturing of this class of materials.
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Impact of Hfq on global gene expression and intracellular survival in Brucella melitensis.
PLoS ONE
PUBLISHED: 01-01-2013
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Brucella melitensis is a facultative intracellular bacterium that replicates within macrophages. The ability of brucellae to survive and multiply in the hostile environment of host macrophages is essential to its virulence. The RNA-binding protein Hfq is a global regulator that is involved in stress resistance and pathogenicity. Here we demonstrate that Hfq is essential for stress adaptation and intracellular survival in B. melitensis. A B. melitensis hfq deletion mutant exhibits reduced survival under environmental stresses and is attenuated in cultured macrophages and mice. Microarray-based transcriptome analyses revealed that 359 genes involved in numerous cellular processes were dysregulated in the hfq mutant. From these same samples the proteins were also prepared for proteomic analysis to directly identify Hfq-regulated proteins. Fifty-five proteins with significantly affected expression were identified in the hfq mutant. Our results demonstrate that Hfq regulates many genes and/or proteins involved in metabolism, virulence, and stress responses, including those potentially involved in the adaptation of Brucella to the oxidative, acid, heat stress, and antibacterial peptides encountered within the host. The dysregulation of such genes and/or proteins could contribute to the attenuated hfq mutant phenotype. These findings highlight the involvement of Hfq as a key regulator of Brucella gene expression and facilitate our understanding of the role of Hfq in environmental stress adaptation and intracellular survival of B. melitensis.
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Inherited variation at chromosome 12p13.33, including RAD52, influences the risk of squamous cell lung carcinoma.
Cancer Discov
PUBLISHED: 12-07-2011
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Although lung cancer is largely caused by tobacco smoking, inherited genetic factors play a role in its etiology. Genome-wide association studies in Europeans have only robustly demonstrated 3 polymorphic variations that influence the risk of lung cancer. Tumor heterogeneity may have hampered the detection of association signal when all lung cancer subtypes were analyzed together. In a genome-wide association study of 5,355 European ever-smoker lung cancer patients and 4,344 smoking control subjects, we conducted a pathway-based analysis in lung cancer histologic subtypes with 19,082 single-nucleotide polymorphisms mapping to 917 genes in the HuGE-defined "inflammation" pathway. We identified a susceptibility locus for squamous cell lung carcinoma at 12p13.33 (RAD52, rs6489769) and replicated the association in 3 independent studies totaling 3,359 squamous cell lung carcinoma cases and 9,100 controls (OR = 1.20, P(combined) = 2.3 × 10(-8)).
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Lateral cavity photonic crystal surface-emitting laser with ultralow threshold.
Opt Lett
PUBLISHED: 11-04-2011
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A lateral cavity photonic crystal (PhC) surface-emitting laser is realized on a commercial epitaxial waveguide wafer without a distributed Bragg reflector first. Energy is coupled from the lateral resonance to surface-emitting light through the ? band edge of the PhC with a square lattice. Electrically driven 1553.8?nm surface-emitting lasing action is observed at room temperature. The threshold current density of 667?A/cm2 is ultralow for the surface-emitting laser.
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Feasibility of fly ash-based composite coagulant for coal washing wastewater treatment.
J. Hazard. Mater.
PUBLISHED: 09-22-2011
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In this study, several fly ash (FA)-based composite coagulants, leached by hydrochloric acid, were prepared to treat coal washing wastewater. The concentrations of Al(3+) and Fe(2+)/Fe(3+) in the leachates and coagulants were analyzed, and optimal experimental conditions, including coagulant dosage and initial pH, were determined using various analytical techniques (scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction (XRD), X-ray fluorescence (XRF), particle-size analysis, zeta potential, pH and conductivity measurements). A suspended solids (SS) and chemical oxygen demand (COD) removal efficiency from the effluent treated by one of the coagulants reached 99.61% and 96.48%, respectively, at dosages of 10 g l(-1) (initial pH of 9, adjusted by CaO). This indicates that the coagulant was an effective agent for coal washing wastewater treatment, and that the leached Al(3+) and Fe(3+) and introduced Ca(2+) may have improved the coagulation process. Analysis of the dry sludge composition and slurry particle size distribution of the coal washing wastewater showed that charged colloidal particles and the fine particle distribution in the coal washing wastewater make the wastewater treatment a difficult process. Results from this study could provide a novel approach for the treatment of coal washing wastewater and coal fly ash utilization.
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DC-SIGN increases the affinity of HIV-1 envelope glycoprotein interaction with CD4.
PLoS ONE
PUBLISHED: 09-16-2011
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Mannose-binding C-type lectin receptors, expressed on Langerhans cells and subepithelial dendritic cells (DCs) of cervico-vaginal tissues, play an important role in HIV-1 capture and subsequent dissemination to lymph nodes. DC-SIGN has been implicated in both productive infection of DCs and the DC-mediated trans infection of CD4(+) T cells that occurs in the absence of replication. However, the molecular events that underlie this efficient transmission have not been fully defined. In this study, we have examined the effect of the extracellular domains of DC-SIGN and Langerin on the stability of the interaction of the HIV-1 envelope glycoprotein with CD4 and also on replication in permissive cells. Surface plasmon resonance analysis showed that DC-SIGN increases the binding affinity of trimeric gp140 envelope glycoproteins to CD4. In contrast, Langerin had no effect on the stability of the gp140:CD4 complex. In vitro infection experiments to compare DC-SIGN enhancement of CD4-dependent and CD4-independent strains demonstrated significantly lower enhancement of the CD4-independent strain. In addition DC-SIGN increased the relative rate of infection of the CD4-dependent strain but had no effect on the CD4-independent strain. DC-SIGN binding to the HIV envelope protein effectively increases exposure of the CD4 binding site, which in turn contributes to enhancement of infection.
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Novel inorganic-organic hybrids constructed from multinuclear copper cluster and Keggin polyanions: from 1D wave-like chain to 2D network.
Dalton Trans
PUBLISHED: 08-11-2011
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Two novel inorganic-organic hybrids constructed from Keggin-type polyanions and multinuclear copper clusters based on 1-H-1,2,3-benzotriazole (HBTA), [Cu(I)(8)(BTA)(4)(HBTA)(8)(SiMo(12)O(40))]·2H(2)O (1) and [Cu(II)(6)(OH)(4)(BTA)(4)(SiW(12)O(40))(H(2)O)(6)]·6H(2)O (2), have been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, elemental analyses, IR spectra and thermogravimetric (TG) analyses. In compound 1, eight Cu(I) ions were linked by twelve HBTA/BTA ligands to form an octanuclear Cu(I) cluster, which is connected by SiMo(12)O(40)(4-) anion with two bridging O atoms and two terminal O atoms to construct a one-dimensional (1D) wave-like chain. The octanuclear copper unit represents the maximum subunit linked just by amine ligands in the POMs system. In 2, four BTA ligands linked five Cu(II) ions constructing a pentanuclear "porphyrin-like" subunit, which is connected by another Cu(II) ion to form a 1D metal-organic band. The SiW(12)O(40)(4-) polyanions as tetradentate inorganic linkages extend the 1D band into a two-dimensional (2D) network with (8(3))(2)(8(5)·10) topology. To the best of our knowledge, compounds 1 and 2 represent the first examples of inorganic-organic hybrids based on metal-HBTA multinuclear subunits and polyoxometalates. The photocatalysis and electrochemical properties have been investigated in this paper.
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Induction of innate immunity in control of mucosal transmission of HIV.
Curr Opin HIV AIDS
PUBLISHED: 07-08-2011
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To present evidence of the role of innate mucosal immunity and to harness this arm of immunity in protection against HIV infection.
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Optical properties of the crescent and coherent applications.
Opt Express
PUBLISHED: 06-07-2011
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By out-of-particle surface plasmon (SP) excitation in the near infrared range, the influences of key parameters on the basic optical properties of the Au crescent are qualitatively studied from the mode dispersion. Based on the coherent control of SP wave, a crescent pair sensor with the intensified extracted signal and the controllability of sensing is proposed. In addition, the crescent half replaced by Ag functioning as a position detector is also proposed. The particular phase of the detecting light as a detection parameter is used to improve the accuracy of the position detection.
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Variation in TP63 is associated with lung adenocarcinoma in the UK population.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 05-24-2011
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Variation at TP63 has recently been shown to be associated with lung adenocarcinoma in the Asian population.
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[Determination of baclofen using micellar electrokinetic chromatography with laser induced fluorescence detection].
Se Pu
PUBLISHED: 05-19-2011
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A novel micellar electrokinetic chromatographic method with laser induced fluorescence detection after derivatization with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) was developed for the determination of muscle relaxant drug baclofen (BAL). After optimization, baseline separation of the derivatives of BAL and gabapentin (internal standard) was obtained within 7 min in a running buffer (pH 9.75) composed of 15 mmol/L sodium borate, 20 mmol/L sodium dodecyl sulfate and 10% (v/v) acetonitrile. The separation voltage was 17.5 kV. The column temperature was 25 degrees C. The samples were injected by a pressure of 3.45 kPa (0.5 psi) for 3 s. The method has a linear range of 0.025 - 25 mg/L for BAL with the correlation coefficient of 0.999 9. The limit of detection (LOD, S/N = 3) and the limit of quantification (LOQ, S/N = 10) were 0.90 microg/L and 6.25 microg/L, respectively. The developed method was used for the analysis of BAL pharmaceutical preparation and urine samples spiked with BAL standard. The ranges of recovery were 101.6% - 107.9% for BAL preparation and 107.0% - 109.6% for urine samples. This method can be applied to the quality assessment of baclofen drug products, and provide supplementary means for the drug metabolism research of baclofen.
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Bis(?-N,N,N-tri-3-pyridylpyridine-1,3,5-tricarboxamide-?N:N)bis-[di-chloridomercury(II)] methanol disolvate.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 05-17-2011
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The title dinuclear centrosymmetric complex, [Hg(2)Cl(4)(C(24)H(18)N(6)O(3))(2)]·2CH(3)OH, comprises Hg(II) atoms coordinated by two Cl atoms and two N atoms from ligands in a distorted tetra-hedral geometry. The solvent mol-ecules are linked by hydrogen bonds.
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Development of an extended multilocus sequence typing for genotyping of Brucella isolates.
J. Microbiol. Methods
PUBLISHED: 04-27-2011
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By amplifying and sequencing longer sequences, an extended multi locus sequence typing (EMLST) theme was developed for Brucella. 61 isolates were genotyped by the EMLST with increased resolution. This strategy could be extended to other bacteria to improve MLST genotyping resolution without additional loci.
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Immunization with recombinant HLA classes I and II, HIV-1 gp140, and SIV p27 elicits protection against heterologous SHIV infection in rhesus macaques.
J. Virol.
PUBLISHED: 04-13-2011
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Major histocompatibility complex (MHC) molecules expressed on the surface of human immunodeficiency virus (HIV) are potential targets for neutralizing antibodies. Since MHC molecules are polymorphic, nonself MHC can also be immunogenic. We have used combinations of novel recombinant HLA class I and II and HIV/simian immunodeficiency virus (SIV) antigens, all linked to dextran, to investigate whether they can elicit protective immunity against heterologous simian/human immunodeficiency virus (SHIV) challenge in rhesus macaques. Three groups of animals were immunized with HLA (group 1, n = 8), trimeric YU2 HIV type 1 (HIV-1) gp140 and SIV p27 (HIV/SIV antigens; group 2, n = 8), or HLA plus HIV/SIV antigens (group 3, n = 8), all with Hsp70 and TiterMax Gold adjuvant. Another group (group 4, n = 6) received the same vaccine as group 3 without TiterMax Gold. Two of eight macaques in group 3 were completely protected against intravenous challenge with 18 50% animal infective doses (AID(50)) of SHIV-SF162P4/C grown in human cells expressing HLA class I and II lineages represented in the vaccine, while the remaining six macaques showed decreased viral loads compared to those in unimmunized animals. Complement-dependent neutralizing activity in serum and high levels of anti-HLA antibodies were elicited in groups 1 and 3, and both were inversely correlated with the plasma viral load at 2 weeks postchallenge. Antibody-mediated protection was strongly supported by the fact that transfer of pooled serum from the two challenged but uninfected animals protected two naïve animals against repeated low-dose challenge with the same SHIV stock. This study demonstrates that immunization with recombinant HLA in combination with HIV-1 antigens might be developed into an alternative strategy for a future AIDS vaccine.
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Controllable corrugation of chemically converted graphene sheets in water and potential application for nanofiltration.
Chem. Commun. (Camb.)
PUBLISHED: 04-13-2011
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A combination of AFM, SEM and permeation experiments suggests that the amplitude of corrugation of chemically converted graphene (CCG) sheets in water can be readily controlled by hydrothermal treatment, leading to a new class of permeation-tuneable nanofiltration membranes.
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Chromosome 15q25 (CHRNA3-CHRNA5) variation impacts indirectly on lung cancer risk.
PLoS ONE
PUBLISHED: 03-28-2011
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Genetic variants at the 15q25 CHRNA5-CHRNA3 locus have been shown to influence lung cancer risk however there is controversy as to whether variants have a direct carcinogenic effect on lung cancer risk or impact indirectly through smoking behavior. We have performed a detailed analysis of the 15q25 risk variants rs12914385 and rs8042374 with smoking behavior and lung cancer risk in 4,343 lung cancer cases and 1,479 controls from the Genetic Lung Cancer Predisposition Study (GELCAPS). A strong association between rs12914385 and rs8042374, and lung cancer risk was shown, odds ratios (OR) were 1.44, (95% confidence interval (CI): 1.29-1.62, P?=?3.69×10(-10)) and 1.35 (95% CI: 1.18-1.55, P?=?9.99×10(-6)) respectively. Each copy of risk alleles at rs12914385 and rs8042374 was associated with increased cigarette consumption of 1.0 and 0.9 cigarettes per day (CPD) (P?=?5.18×10(-5) and P?=?5.65×10(-3)). These genetically determined modest differences in smoking behavior can be shown to be sufficient to account for the 15q25 association with lung cancer risk. To further verify the indirect effect of 15q25 on the risk, we restricted our analysis of lung cancer risk to never-smokers and conducted a meta-analysis of previously published studies of lung cancer risk in never-smokers. Never-smoker studies published in English were ascertained from PubMed stipulating--lung cancer, risk, genome-wide association, candidate genes. Our study and five previously published studies provided data on 2,405 never-smoker lung cancer cases and 7,622 controls. In the pooled analysis no association has been found between the 15q25 variation and lung cancer risk (OR?=?1.09, 95% CI: 0.94-1.28). This study affirms the 15q25 association with smoking and is consistent with an indirect link between genotype and lung cancer risk.
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CoMOR zeolite catalyst prepared by buffered ion exchange for effective decomposition of nitrous oxide.
J. Hazard. Mater.
PUBLISHED: 03-27-2011
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Co contained MOR zeolite catalysts with high Co loadings were successfully synthesized by buffered ion exchange at pH 8, and were tested for N(2)O catalytic decomposition. The high exchange level of synthesized CoMOR(x)-BIE catalysts probably benefits from the maximizing hydroxycomplexes Co(OH)(+) ion in the buffered solution, which is more preferred for the ion exchange with the zeolites. It has been found that the novel CoMOR(x)-BIE catalysts exhibit excellent catalytic activities, which is attributed to the large population of isolated Co(2+) ions on ion exchange positions. The most active CoMOR(130)-BIE catalyst shows high resistance to the inhibition of oxygen, NO and water vapor. Furthermore, stability tests indicate that the CoMOR(130)-BIE catalyst has no obvious deactivation under simulated emission conditions after reaction for more than 100 h. This extraordinary durability could be related to its high Co(2+) content and low Brönsted acidity sites in the catalyst, which facilitate the stability of active isolated Co(2+) on ion exchange positions. Thus, the CoMOR(130)-BIE catalyst shows a great potential as a cost-effective catalyst for N(2)O elimination in future applications.
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The 16M?vjbR as an ideal live attenuated vaccine candidate for differentiation between Brucella vaccination and infection.
Vet. Microbiol.
PUBLISHED: 03-22-2011
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Brucellosis brings great economic burdens for developing countries. Live attenuated vaccines are the most efficient means for prevention and control of animal Brucellosis. However, the difficulties of differentiating of infection from vaccine immunization, which is essential for eradication programs, limit their applications. Therefore, the development of a vaccine that could differentiate infection from immunization will overcome the limitations and get extensive application. VjbR is a quorum sensing regulator involving in Brucellas intracellular survival. The vjbR?Tn5 mutants have been proven effective against wild type strain challenge, implying its possibility of use in vaccine candidate development. To further evaluate this candidate gene, in the present study, the antigenicity of purified recombinant VjbR protein was analyzed. Antibodies to Brucella melitensis VjbR could be detected in sera from patients and animals with brucellosis but not in control ones, implying the potential use of this protein as a diagnostic antigen. Then a vjbR mutant of B. melitensis 16M was constructed by replacing the vjbR with kanamycin gene. The mutant showed reduced survival in macrophage and mice. Vaccination of BALB/c mice with 16M?vjbR conferred significant protective immunity against B. melitensis strain 16M challenges, being equivalent to which induced by the license vaccine Rev.1. The vjbR deletion mutant elicited an anti-Brucella-specific immunoglobulin G response and induced the secretion of gamma interferon and interleukin-10. The most importance is that, the use of vjbR mutants as vaccines in association with diagnostic tests based on the VjbR antigen would allow the serological differentiation between infected and vaccinated animals. These results suggest that 16M?vjbR is an ideal live attenuated vaccine candidate against B. melitensis and deserves further evaluation for vaccine development.
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Adsorption and desorption performance of benzene over hierarchically structured carbon-silica aerogel composites.
J. Hazard. Mater.
PUBLISHED: 03-09-2011
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Hierarchically structured carbon-silica aerogel (CSA) composites were synthesized from cheap water glass precursors and granulated activated carbon via a post-synthesis surface modification with trimethylchlorosilane (TMCS) and a low-cost ambient pressure drying procedure. The resultant CSA composites possess micro/mesoporous structure and hydrophobic surface. The adsorption and desorption performance of benzene on carbon-silica aerogel composite (CSA-2) under static and dynamic conditions were investigated, comparing with pure silica aerogel (CSA-0) and microporous activated carbon (AC). It was found that CSA-2 has high affinity towards aromatic molecules and fast adsorption kinetics. Excellent performance of dynamic adsorption and desorption observed on CSA-2 is related to its higher adsorption capacity than CSA-0 and less mass transfer resistance than AC, arising from the well-developed microporosity and open foam mesostructure in the CSA composites.
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Association of a novel functional promoter variant (rs2075533 C>T) in the apoptosis gene TNFSF8 with risk of lung cancer--a finding from Texas lung cancer genome-wide association study.
Carcinogenesis
PUBLISHED: 02-02-2011
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Published genome-wide association studies (GWASs) have identified few variants in the known biological pathways involved in lung cancer etiology. To mine the possibly hidden causal single nucleotide polymorphisms (SNPs), we explored all SNPs in the extrinsic apoptosis pathway from our published GWAS dataset for 1154 lung cancer cases and 1137 cancer-free controls. In an initial association analysis of 611 tagSNPs in 41 apoptosis-related genes, we identified only 10 tagSNPs associated with lung cancer risk with a P value<10(-2), including four tagSNPs in DAPK1 and three tagSNPs in TNFSF8. Unlike DAPK1 SNPs, TNFSF8 rs2181033 tagged other four predicted functional but untyped SNPs (rs776576, rs776577, rs31813148 and rs2075533) in the promoter region. Therefore, we further tested binding affinity of these four SNPs by performing the electrophoretic mobility shift assay. We found that only rs2075533T allele modified levels of nuclear proteins bound to DNA, leading to significantly decreased expression of luciferase reporter constructs by 5- to -10-fold in H1299, HeLa and HCT116 cell lines compared with the C allele. We also performed a replication study of the untyped rs2075533 in an independent Texas population but did not confirm the protective effect. We further performed a mini meta-analysis for SNPs of TNFSF8 obtained from other four published lung cancer GWASs with 12 ?214 cases and 47? 721 controls, and we found that only rs3181366 (r2=0.69 with the untyped rs2075533) was associated to lung cancer risk (P=0.008). Our findings suggest a possible role of novel TNFSF8 variants in susceptibility to lung cancer.
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An analysis of single nucleotide polymorphisms of 125 DNA repair genes in the Texas genome-wide association study of lung cancer with a replication for the XRCC4 SNPs.
DNA Repair (Amst.)
PUBLISHED: 01-09-2011
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DNA repair genes are important for maintaining genomic stability and limiting carcinogenesis. We analyzed all single nucleotide polymorphisms (SNPs) of 125 DNA repair genes covered by the Illumina HumanHap300 (v1.1) BeadChips in a previously conducted genome-wide association study (GWAS) of 1154 lung cancer cases and 1137 controls and replicated the top-hits of XRCC4 SNPs in an independent set of 597 cases and 611 controls in Texas populations. We found that six of 20 XRCC4 SNPs were associated with a decreased risk of lung cancer with a P-value of 0.01 or lower in the discovery dataset, of which the most significant SNP was rs10040363 (P for allelic test=4.89 x 10??). Moreover, the data in this region allowed us to impute a potentially functional SNP rs2075685 (imputed P for allelic test=1.3 x 10?³). A luciferase reporter assay demonstrated that the rs2075685G>T change in the XRCC4 promoter increased expression of the gene. In the replication study of rs10040363, rs1478486, rs9293329, and rs2075685, however, only rs10040363 achieved a borderline association with a decreased risk of lung cancer in a dominant model (adjusted OR=0.80, 95% CI=0.62-1.03 and P=0.079). In the final combined analysis of both the Texas GWAS discovery and replication datasets, the strength of the association was increased for rs10040363 (adjusted OR=0.77, 95% CI=0.66-0.89, P(dominant)=5 x 10?? and P for trend=5 x 10??) and rs1478486 (adjusted OR=0.82, 95% CI=0.71-0.94, P(dominant)=6 x 10?³ and P for trend=3.5 x 10?³). Finally, we conducted a meta-analysis of these XRCC4 SNPs with available data from published GWA studies of lung cancer with a total of 12,312 cases and 47,921 controls, in which none of these XRCC4 SNPs was associated with lung cancer risk. It appeared that rs2075685, although associated with increased expression of a reporter gene and lung cancer risk in the Texas populations, did not have an effect on lung cancer risk in other populations. This study underscores the importance of replication using published data in larger populations.
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MHC variation and risk of childhood B-cell precursor acute lymphoblastic leukemia.
Blood
PUBLISHED: 11-08-2010
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A role for specific human leukocyte antigen (HLA) variants in the etiology of childhood acute lymphoblastic leukemia (ALL) has been extensively studied over the last 30 years, but no unambiguous association has been identified. To comprehensively study the relationship between genetic variation within the 4.5 Mb major histocompatibility complex genomic region and precursor B-cell (BCP) ALL risk, we analyzed 1075 observed and 8176 imputed single nucleotide polymorphisms and their related haplotypes in 824 BCP-ALL cases and 4737 controls. Using these genotypes we also imputed both common and rare alleles at class I (HLA-A, HLA-B, and HLA-C) and class II (HLA-DRB1, HLA-DQA1, and HLA-DQB1) HLA loci. Overall, we found no statistically significant association between variants and BCP-ALL risk. We conclude that major histocompatibility complex-defined variation in immune-mediated response is unlikely to be a major risk factor for BCP-ALL.
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[Determination of gabapentin using capillary electrophoresis with laser-induced fluorescence detection].
Se Pu
PUBLISHED: 09-21-2010
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A novel method for the determination of gabapentin (an antiepileptic drug) has been developed using capillary electrophoresis with laser-induced fluorescence detection (LIFD). Gabapentin was first derived by 4-chloro-7-nitrobenzofurazan (NBD-Cl) and baseline separated within 6 min with a running buffer consisting of 10 mmol/L borate sodium and 10 mmol/L sodium dodecyl sulfate (pH 9.75). The linear range of this method was 0.01-10 mg/L (r = 0.9997) with the limit of detection (LOD) of 2 microg/L and the limit of quantification (LOQ) of 10 microg/L. The average recoveries were 100.2%-103.1% with the relative standard deviation (RSD) of 0.15%-1.00%. This method is fast, sensitive, accurate and reliable, and it has been used successfully for the quality assessment of gabapentin drug products.
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[Analysis of 43 pesticide residues in vegetables using solid-phase extraction and gas chromatography-triple quadrupole mass spectrometry].
Se Pu
PUBLISHED: 09-21-2010
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A method for the simultaneous analysis of 43 pesticide residues in vegetables by gas chromatography coupled with triple quadrupole mass spectrometry (GC-QqQ-MS/MS) was developed and validated. The samples were extracted with acetonitrile, and then purified by solid-phase extraction (SPE). The detection of 43 pesticides was carried out by GC-QqQ-MS/MS in the multi-reaction monitoring (MRM) mode using external standard method. The overall recoveries determined at three spiked levels of 10, 80 and 100 microg/kg were 62.2%-170.0%, which in the recoveries of 36 pesticides were 70.0%-120.0%. The relative standard deviations (RSDs) were less than 18%. The limits of quantification (S/N > or =10) were 0.3-4.4 microg/kg. The method possesses low background and high sensitivity. It can be applied to the routine analysis of the 43 pesticides in vegetables.
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Stress-activated dendritic cells interact with CD4+ T cells to elicit homeostatic memory.
Eur. J. Immunol.
PUBLISHED: 04-15-2010
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Evidence is presented that thermal or oxidizing stress-activated DC interact with CD4(+) T cells to induce and maintain a TCR-independent homeostatic memory circuit. Stress-activated DC expressed endogenous intra-cellular and cell surface HSP70. The NF-kappaB signalling pathway was activated and led to the expression of membrane-associated IL-15 molecules. These interacted with the IL-15 receptor complex on CD4(+) T cells, thus activating the Jak3 and STAT5 phosphorylation signalling pathway to induce CD40 ligand expression, T-cell proliferation and IFN-gamma production. CD40 ligand on CD4(+) T cells in turn re-activated CD40 molecules on DC, inducing DC maturation and IL-15 expression thereby maintaining the feedback circuit. The proliferating CD4(+) T cells were characterized as CD45RA(-) CD62L(+) central memory cells, which underwent homeostatic proliferation. The circuit is independent of antigen and MHC-class-II-TCR interaction as demonstrated by resistance to TCR inhibition by ZAP70 inhibitor or MHC-class II antibodies. These findings suggest that stress can activate a DC-CD4(+) T-cell interacting circuit, which may be responsible for maintaining a homeostatic antigen-independent memory.
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Ligand-assisted preparation of highly active and stable nanometric Pd confined catalysts for deep catalytic oxidation of toluene.
J. Hazard. Mater.
PUBLISHED: 03-22-2010
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In this study, mesoporous SBA-15 supported Pd catalysts were synthesized through impregnation and grafting approaches. Moreover, the influences of different solvents (ethanol, H(2)O, tetrahydrofuran, dimethyl sulphoxide and N,N-dimethylformamide) on the dispersion of supported Pd nanoparticles were also systematically investigated. The prepared materials were comprehensively explored by various techniques, including XRD, EDS, ICP-OES, H(2) chemisorption, N(2) adsorption/desorption, TG-DSC, FT-IR, TEM and STEM. It is found that the traditional impregnation method has some disadvantages in obtaining highly dispersed Pd active phase. Whereas, the grafting method could highly disperse Pd nanoparticles within the mesoporous channels of support material, and the grafting procedure should be promising in designing highly dispersed Pd particles on the silica-based mesoporous materials. The catalyst prepared via the grafting procedure possesses much higher activity and selectivity than that prepared by impregnation method for deep catalytic oxidation of toluene.
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Multiple independent loci at chromosome 15q25.1 affect smoking quantity: a meta-analysis and comparison with lung cancer and COPD.
PLoS Genet.
PUBLISHED: 02-23-2010
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Recently, genetic association findings for nicotine dependence, smoking behavior, and smoking-related diseases converged to implicate the chromosome 15q25.1 region, which includes the CHRNA5-CHRNA3-CHRNB4 cholinergic nicotinic receptor subunit genes. In particular, association with the nonsynonymous CHRNA5 SNP rs16969968 and correlates has been replicated in several independent studies. Extensive genotyping of this region has suggested additional statistically distinct signals for nicotine dependence, tagged by rs578776 and rs588765. One goal of the Consortium for the Genetic Analysis of Smoking Phenotypes (CGASP) is to elucidate the associations among these markers and dichotomous smoking quantity (heavy versus light smoking), lung cancer, and chronic obstructive pulmonary disease (COPD). We performed a meta-analysis across 34 datasets of European-ancestry subjects, including 38,617 smokers who were assessed for cigarettes-per-day, 7,700 lung cancer cases and 5,914 lung-cancer-free controls (all smokers), and 2,614 COPD cases and 3,568 COPD-free controls (all smokers). We demonstrate statistically independent associations of rs16969968 and rs588765 with smoking (mutually adjusted p-values<10(-35) and <10(-8) respectively). Because the risk alleles at these loci are negatively correlated, their association with smoking is stronger in the joint model than when each SNP is analyzed alone. Rs578776 also demonstrates association with smoking after adjustment for rs16969968 (p<10(-6)). In models adjusting for cigarettes-per-day, we confirm the association between rs16969968 and lung cancer (p<10(-20)) and observe a nominally significant association with COPD (p = 0.01); the other loci are not significantly associated with either lung cancer or COPD after adjusting for rs16969968. This study provides strong evidence that multiple statistically distinct loci in this region affect smoking behavior. This study is also the first report of association between rs588765 (and correlates) and smoking that achieves genome-wide significance; these SNPs have previously been associated with mRNA levels of CHRNA5 in brain and lung tissue.
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A recombinant human HLA-class I antigen linked to dextran elicits innate and adaptive immune responses.
J. Immunol. Methods
PUBLISHED: 02-23-2010
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The objective of this study was to produce and evaluate the immunogenic potential of a recombinant HLA-class I antigen linked to dextran. The HLA-A*0201 heavy chain and beta2 microglobulin were cloned by PCR amplification of overlapping oligonucleotides and produced in E. coli. These were assembled with a CMV binding peptide motif, the HLA complex was biotinylated and bound by streptavidin coated dextran at a ratio of 24 HLA to 1 dextran molecule (termed Dextramer). Allostimulation of human PBMC in vitro and in vivo immunization of Balb c mice with the HLA-A*0201 construct elicited CD4+ and CD8+ T cell proliferative responses, IgG specific antibodies in mice and in human T cell proliferation and APOBEC3G mRNA. These adaptive and innate immune responses induced by a novel recombinant HLA construct in human cells and mice suggest their application as a potential vaccine candidate against HIV infection.
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Concentration effect of gold nanoparticles on proliferation of keratinocytes.
Colloids Surf B Biointerfaces
PUBLISHED: 02-03-2010
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34 nm gold nanoparticles with good stability were synthesized and characterized and their effect (as a function of concentration) on the proliferation of keratinocytes was evaluated by means of MTT and nucleolar organizer region (AgNOR) count (silver staining). The cell morphology was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results demonstrate that a low concentration of gold nanoparticles enhances the proliferation of keratinocytes. Specifically, a concentration of 5.0 ppm gold nanoparticle has the best effect on the promotion of cell growth. In the experiment group, the AgNOR-positive areas and AgNOR area/nuclear area ratios of keratinocytes co-cultured with 5.0 ppm gold nanoparticles were greater than those in the control group (p<0.01). At a level greater than 10.0 ppm, gold nanoparticles were found to have a cytotoxic effect on keratinocytes. It is concluded that a low concentration of gold nanoparticles may be used as a biomedical material in skin tissue engineering.
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Role of 5p15.33 (TERT-CLPTM1L), 6p21.33 and 15q25.1 (CHRNA5-CHRNA3) variation and lung cancer risk in never-smokers.
Carcinogenesis
PUBLISHED: 12-02-2009
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Genome-wide association studies have provided evidence that common variation at 5p15.33 (TERT-CLPTM1L), 6p21.33 and 15q25.1 (CHRNA5-CHRNA3) influences lung cancer risk. To examine if variation at any of these loci influences the risk of lung cancer in never-smokers, we compared 5p15.33-TERT (rs2736100), 5p15.33-CLPTM1L (rs4975616), 6p21.33-BAT3 (rs3117582), 15q25.1-CHRNA3 (rs8042374) and 15q25.1-CHRNA3 (rs12914385) genotypes in a series of 239 never-smoker lung cancer cases and 553 never-smoker controls. A statistically significant association between lung cancer risk and 5p15.33 genotypes was found: rs2736100 (odds ratio = 0.78, 95% confidence interval: 0.63-0.97; P = 0.02), rs4975616 (odds ratio = 0.69, 95% confidence interval: 0.55-0.85; P = 7.95 x 10(-4)), primarily for adenocarcinoma. There was no evidence of association between 6p21.33 or 15q25.1 variation and risk of lung cancer. This analysis provides evidence that TERT-CLPTM1L variants may influence the risk of lung cancer outside the context of tobacco smoking.
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The type IV secretion system affects the expression of Omp25/Omp31 and the outer membrane properties of Brucella melitensis.
FEMS Microbiol. Lett.
PUBLISHED: 11-23-2009
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The type IV secretion system (T4SS) contributes to Brucella intracellular survival through its effector proteins. Comparative proteomic analysis showed that intracellular survival proteins are expressed differentially in a virB mutant. Interestingly, several outer membrane proteins (OMPs) are also differentially expressed, implying that T4SS might affect the OM properties of Brucella. To further evaluate the impact of T4SS on OM, in the present study, the OM proteomes were isolated and compared. Many more products of OMPs, particularly different products of the Omp25/Omp31 family, were found to be altered in the virB mutant. The transcription profiles of Omp25/Omp31 were different from those of their protein products, implying their regulation by virB at both transcriptional and post-transcriptional levels. The virB mutant aggregates at a high cell density and produces exopolysaccharide, a phenotype resembling that of the vjbR mutant. The virB mutant showed increased sensitivity to polymyxin B and decreased survival under oxidative, high-salt and high-osmolarity stresses, indicating drastic membrane alterations. These results indicated that in addition to being an effector protein secretion system, T4SS affects OM properties that might be important for the adaptation of Brucella to both in vitro and in vivo hostile environments.
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catena-Poly[[[acetonitrile-copper(I)]-bis-[?-bis-(diphenyl-phosphino)methane-?P:P]-copper(I)-?-1,2-di-4-pyridy-l-ethene] bis-(tetra-fluoridoborate)].
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 09-13-2009
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The title dinuclear copper(I) complex, {[Cu(2)(C(2)H(3)N)(C(12)H(10)N(2))(C(25)H(22)P(2))(2)](BF(4))(2)}(n), contains 1,2-di-4-pyridyl-ethene, bis-(diphenyl-phosphino)methane and acetonitrile ligands. The two Cu atoms, one with an N(2)P(2) ligand set and the other with an NP(2) ligand set, are bridged by two bis-(diphenyl-phosphino)methane ligands, forming an eight-membered ring.
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[A prime-boost vaccination strategy using a Semliki Forest virus replicon vectored DNA vaccine followed by a recombinant adenovirus protects pigs from classical swine fever].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 08-13-2009
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We have previously evaluated a Semliki Forest virus (SFV) replicon vectored DNA vaccine (pSFV1CS2-E2) and a recombinant adenovirus (rAdV-E2) expressing the E2 glycoprotein of classical swine fever virus (CSFV) in pigs. The results showed that the immunized pigs were protected from virulent challenge, but few pigs showed short-term fever and occasional pathological changes following virulent challenge. To enhance the immunogenecity of the vaccines, we tried a prime-boost vaccination strategy using a combination of prime with pSFV1CS2-E2 followed by boost with rAdV-E2. The results showed that all the immunized pigs developed high-level CSFV-specific antibodies following prime-boost immunization. When challenged with virulent CSFV, the immunized pigs (n = 5) from the heterologous boost group showed no clinical symptoms, and CSFV RNA was not detected following challenge, whereas one of five pigs from the homologous boost group developed short-term fever and CSFV RNA was detected. This demonstrates that the heterologous prime-boost vaccination regime has the potential to prevent against virulent challenge.
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Deciphering the impact of common genetic variation on lung cancer risk: a genome-wide association study.
Cancer Res.
PUBLISHED: 08-04-2009
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To explore the impact of common variation on the risk of developing lung cancer, we conducted a two-phase genome-wide association (GWA) study. In phase 1, we compared the genotypes of 511,919 tagging single nucleotide polymorphisms (SNP) in 1,952 cases and 1,438 controls; in phase 2, 30,568 SNPs were genotyped in 2,465 cases and 3,005 controls. SNP selection was based on best supported P values from phase 1 and two other GWA studies of lung cancer. In the combined analysis of phases 1 and 2, the strongest associations identified were defined by SNPs mapping to 15q25.1 (rs12914385; P = 3.19 x 10(-16)), 5p15.33 (rs4975616; P = 6.66 x 10(-7)), and 6p21.33 (rs3117582; P = 9.13 x 10(-7)). Variation at 15q25.1, but not 5p15.33 or 6p21.33, was strongly associated with smoking behavior with risk alleles correlated to higher consumption. Variation at 5p15.33 was shown to significantly influence induction of lung cancer histology. Pooling data from the four series provided 21,620 genotypes for 7,560 cases and 8,205 controls. A meta-analysis provided increased support that variation at 15q25.1 (rs8034191; P = 3.24 x 10(-26)), 5p15.33 (rs4975616; P = 2.99 x 10(-9)), and 6p21.33 (rs3117582; P = 4.46 x 10(-10)) influences lung cancer risk. The next best-supported associations were attained at 15q15.2 (rs748404: P = 1.08 x 10(-6)) and 10q23.31 (rs1926203; P = 1.28 x 10(-6)). These data indicate few common variants account for 1% of the excess familial risk underscoring the necessity of having additional large sample series for gene discovery.
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[Construction of BP26 tagged vaccine strain and development of discriminating PCR for Brucella].
Wei Sheng Wu Xue Bao
PUBLISHED: 07-24-2009
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The wide application of live attenuated vaccine strains is limited because of drawbacks of residual virulence, similar antigenenicity to virulent strain and the difficulty to differentiate vaccination and natural infection. In this study, we modified the vaccine strain to prevent the drawbacks.
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Cytotoxicity of Brucella smooth strains for macrophages is mediated by increased secretion of the type IV secretion system.
Microbiology (Reading, Engl.)
PUBLISHED: 07-23-2009
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Some Brucella rough mutants cause cytotoxicity that resembles oncosis and necrosis in macrophages. This cytotoxicity requires the type IV secretion system (T4SS). In rough mutants, the cell-surface O antigen is shortened and the T4SS structure is thus exposed on the surface. Cytotoxicity effector proteins can therefore be more easily secreted. This enhanced secretion of effector proteins might cause the increased levels of cytotoxicity observed. However, whether this cytotoxicity is unique to the rough mutant and is mediated by overexpression of the T4SS has not been definitively determined. To test this, in the present study, a virB inactivation mutant (BMDeltavirB) and an overexpression strain (BM-VIR) of a smooth Brucella melitensis strain (BM) were constructed and their cytotoxicity for macrophages and intracellular survival capability were analysed and compared. Cytotoxicity was detected in macrophages infected with higher concentrations of strains BM or BM-VIR, but not in those infected with BMDeltavirB. The quorum sensing signal molecule N-dodecanoyl-dl-homoserine lactone (C(12)-HSL), a molecule that can inhibit expression of virB, inhibited the cytotoxicity of BM and BM-VIR, but not of BMDeltavirB. These results indicated that overexpression of virB is responsible for Brucella cytotoxicity in macrophages. Transcription analysis showed that virB is regulated in a cell-density-dependent manner both in in vitro culture and during macrophage infection. When compared with BM, BM-VIR showed a reduced survival capacity in macrophages and mice, but both strains demonstrated similar resistance to in vitro stress conditions designed to simulate intracellular environments. Taken together, the cytotoxicity of Brucella for macrophages is probably mediated by increased secretion of effector proteins that results from overexpression of virB or an increase in the number of bacterial cells. The observation that both inactivation and overexpression of virB are detrimental for Brucella intracellular survival also indicated that the expression of virB is tightly regulated in a cell-density-dependent manner.
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Noninvasive visualization of retinoblastoma growth and metastasis via bioluminescence imaging.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 07-15-2009
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To establish human retinoblastoma (RB) animal models that allow sensitive, noninvasive and continuous monitoring of tumor growth and metastasis in vivo.
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The effect of allogeneic in vitro stimulation and in vivo immunization on memory CD4(+) T-cell APOBEC3G expression and HIV-1 infectivity.
Eur. J. Immunol.
PUBLISHED: 07-09-2009
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Allogeneic immunity is one of the most potent natural immune responses. APOBEC3G (A3G) is an intracellular anti-viral factor that deaminates cytidine to uridine. Allogeneic stimulation of human CD4(+) T cells in vitro upregulated A3G mRNA and a significant correlation was found between the mixed leukocyte reaction and A3G mRNA. The mechanism of upregulation of A3G mRNA involves interaction between HLA on DC and TCR of CD4(+) T cells, which is ZAP70 and downstream ERK phosphokinase signalling dependent and induces CD40L and A3G mRNA expression in CD4(+) T cells. Alloimmune-induced A3G was found to be significantly increased in CD45RA(-), CCR5(+) and CD45RA(-)CCR7(-) subsets of effector memory T cells. In vivo studies of women alloimmunized with their partners PBMC also showed a significant increase in A3G protein in CD4(+) T cells, CD45RO(+) memory and CCR7(-) effector memory T cells. The functional effect of allostimulation upregulating A3G mRNA was demonstrated by a significant decrease in in vitro infectivity, using GFP-labelled pseudovirus and confirmed by a decrease in HIV-1 (BaL) infection of primary CD4(+) T cells. The results suggest that alloimmunization offers an alternative or complementary strategy in inducing an innate anti-viral factor that inhibits HIV-1 infection.
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A genome-wide association study of lung cancer identifies a region of chromosome 5p15 associated with risk for adenocarcinoma.
Am. J. Hum. Genet.
PUBLISHED: 07-03-2009
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Three genetic loci for lung cancer risk have been identified by genome-wide association studies (GWAS), but inherited susceptibility to specific histologic types of lung cancer is not well established. We conducted a GWAS of lung cancer and its major histologic types, genotyping 515,922 single-nucleotide polymorphisms (SNPs) in 5739 lung cancer cases and 5848 controls from one population-based case-control study and three cohort studies. Results were combined with summary data from ten additional studies, for a total of 13,300 cases and 19,666 controls of European descent. Four studies also provided histology data for replication, resulting in 3333 adenocarcinomas (AD), 2589 squamous cell carcinomas (SQ), and 1418 small cell carcinomas (SC). In analyses by histology, rs2736100 (TERT), on chromosome 5p15.33, was associated with risk of adenocarcinoma (odds ratio [OR]=1.23, 95% confidence interval [CI]=1.13-1.33, p=3.02x10(-7)), but not with other histologic types (OR=1.01, p=0.84 and OR=1.00, p=0.93 for SQ and SC, respectively). This finding was confirmed in each replication study and overall meta-analysis (OR=1.24, 95% CI=1.17-1.31, p=3.74x10(-14) for AD; OR=0.99, p=0.69 and OR=0.97, p=0.48 for SQ and SC, respectively). Other previously reported association signals on 15q25 and 6p21 were also refined, but no additional loci reached genome-wide significance. In conclusion, a lung cancer GWAS identified a distinct hereditary contribution to adenocarcinoma.
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[Determination of ciprofloxacin residue in fish/shellfish tissues using liquid chromatography-tandem mass spectrometry with isotope internal standard dilution technique].
Se Pu
PUBLISHED: 05-20-2009
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Using isotope internal standard dilution technique, a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed for the identification and quantitative determination of ciprofloxacin residue in the tissues of various fishes/shellfishes. The homogenized tissue sample added with ciprofloxacin-D8 and phosphate buffer solution (pH 7.0) was extracted with acetonitrile under ultrasonication, and degreased with hexane. After solid-phase extraction (SPE) was performed on an Oasis MAX cartridge, the sample was separated on a Cloversil-C18 column (150 mm x 4.6 mm, 5 microm) by using the mobile phase consisting of CH3CN-0.05% CF3 COOH (25:75, v/v). The detection was carried out by LC-MS/MS using an electrospray ionization interface in multiple reaction monitoring (MRM) mode. The quantification using isotope-labelled internal standard was based on the peak area ratio of ciprofloxacin and deuterated internal standard in the MRM mode. The calibration curve was linear within the range of 0.1 - 50.0 microg/kg and the limit of quantification was 0.1 microg/kg (S/N > or = 10). The recovery was between 92.5% and 98.1%, and the relative standard deviation was less than 4.3%. The application of this method was further demonstrated by analyzing ten various real samples from local markets. The results show that this method is sensitive, accurate and suitable for the confirmative determination of ciprofloxacin residues.
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Mucosal immunization in macaques upregulates the innate APOBEC 3G anti-viral factor in CD4(+) memory T cells.
Vaccine
PUBLISHED: 03-28-2009
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APOBEC3G is an innate intracellular anti-viral factor which deaminates retroviral cytidine to uridine. In vivo studies of APOBEC3G (A3G) were carried out in rhesus macaques, following mucosal immunization with SIV antigens and CCR5 peptides, linked to the 70kDa heat shock protein. A progressive increase in A3G mRNA was elicited in PBMC after each immunization (p<0.0002 to p< or =0.02), which was maintained for at least 17 weeks. Analysis of memory T cells showed a significant increase in A3G mRNA and protein in CD4(+)CCR5(+) memory T cells in circulating (p=0.0001), splenic (p=0.0001), iliac lymph nodes (p=0.002) and rectal (p=0.01) cells of the immunized compared with unimmunized macaques. Mucosal challenge with SIVmac 251 showed a significant increase in A3G mRNA in the CD4(+)CCR5(+) circulating cells (p<0.01) and the draining iliac lymph node cells (p<0.05) in the immunized uninfected macaques, consistent with a protective effect exerted by A3G. The results suggest that mucosal immunization in a non-human primate can induce features of a memory response to an innate anti-viral factor in CCR5(+)CD4(+) memory and CD4(+)CD95(+)CCR7(-) effector memory T cells.
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Rapid and quantitative detection of Brucella by up-converting phosphor technology-based lateral-flow assay.
J. Microbiol. Methods
PUBLISHED: 03-26-2009
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A rapid and quantitative up-converting phosphor technology-based later-flow assay (UPT-LF assay) was developed for on-site detection of Brucella. Different Brucella species both in pure cultures and in spiked samples could be quantitatively detected. The detection limit for pure culture was 5 x 10(6)CFU/ml and the sensitivity for different spiked samples ranged from 2.0 x 10(3) to 3.9 x 10(5)CFU/mg. The UPT-LF assay showed high specificity, reproducibility and stability, providing great potential for Brucella on-site detection.
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Oncolytic adenovirus delivering herpes simplex virus thymidine kinase suicide gene reduces the growth of human retinoblastoma in an in vivo mouse model.
Exp. Eye Res.
PUBLISHED: 03-17-2009
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Oncolytic conditionally replicating adenoviruses (CRAd) can exclusively replicate in and lyse tumor cells and are therefore promising tools in cancer therapy. In this study, we combined the oncolytic potential of a CRAd with its ability to deliver a suicide gene (herpes simplex virus thymidine kinase suicide gene, HSVtk) in order to further enhance tumor cell killing in a human retinoblastoma (RB) mouse model. We could demonstrate that CRAd driven by the human telomerase reverse transcriptase (hTERT) promoter and armed with the HSV thymidine kinase suicide gene/ganciclovir (HSVtk/GCV) could very effectively reduce growth of human RB in an orthotopic nude mouse model. These findings suggest that hTERT promoter-driven CRAd in combination with HSVtk/GCV gene therapy could be a promising new approach for the treatment of RB. In addition, we found that hTERT promoter-driven CRAd replication occurred exclusively in human RB cells but not in primary human retinal pigment epithelial cells (hRPE), indicating that application of hTERT promoter-driven CRAd for the treatment of RB would be safe.
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Comparative proteomics analyses reveal the virB of B. melitensis affects expression of intracellular survival related proteins.
PLoS ONE
PUBLISHED: 01-23-2009
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Brucella melitensis is a facultative, intracellular, pathogenic bacterium that replicates within macrophages. The type IV secretion system encoded by the virB operon (virB) is involved in Brucella intracellular survival. However, the underlying molecular mechanisms, especially the target proteins affected by the virB, remain largely unclear.
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Comparison of the A-Cc curve fitting methods in determining maximum ribulose 1.5-bisphosphate carboxylase/oxygenase carboxylation rate, potential light saturated electron transport rate and leaf dark respiration.
Plant Cell Environ.
PUBLISHED: 01-22-2009
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A review of the literature revealed that a variety of methods are currently used for fitting net assimilation of CO2-chloroplastic CO2 concentration (A-Cc) curves, resulting in considerable differences in estimating the A-Cc parameters [including maximum ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco) carboxylation rate (Vcmax), potential light saturated electron transport rate (Jmax), leaf dark respiration in the light (Rd), mesophyll conductance (gm) and triose-phosphate utilization (TPU)]. In this paper, we examined the impacts of fitting methods on the estimations of Vcmax, Jmax, TPU, Rd and gm using grid search and non-linear fitting techniques. Our results suggested that the fitting methods significantly affected the predictions of Rubisco-limited (Ac), ribulose 1,5-bisphosphate-limited (Aj) and TPU-limited (Ap) curves and leaf photosynthesis velocities because of the inconsistent estimate of Vcmax, Jmax, TPU, Rd and gm, but they barely influenced the Jmax : Vcmax, Vcmax : Rd and Jmax : TPU ratio. In terms of fitting accuracy, simplicity of fitting procedures and sample size requirement, we recommend to combine grid search and non-linear techniques to directly and simultaneously fit Vcmax, Jmax, TPU, Rd and gm with the whole A-Cc curve in contrast to the conventional method, which fits Vcmax, Rd or gm first and then solves for Vcmax, Jmax and/or TPU with V(cmax), Rd and/or gm held as constants.
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Altered Transcriptome of the B. melitensis Vaccine Candidate 16M?vjbR, Implications for Development of Genetically Marked Live Vaccine.
Indian J. Microbiol.
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The VjbR protein induced antibody responses in both human and animal brucellosis, and the vjbR mutant 16M?vjbR is an ideal vaccine candidate because of the feasibility of using the VjbR as diagnostic antigen. To further characterize this vaccine candidate and provide information for vaccine development, in the present study, a whole genome DNA microarray of 16M were used to compare the transcriptome of the vjbR mutant to that of the wild type strains. A total of 126 genes were greatly differentially expressed in the vjbR mutant. A great proportion of virB and flagellar genes were differentially expressed in the vjbR mutant, implying that the vjbR regulate expression of virulence genes by sensing intracellular environments. Interestingly, the virB genes are regulated by the vjbR in independent manners as shown by their different fold changes and transcription abundances. A number of genes involved in translation, stress response, amino acid transport and metabolism, cell wall/membrane biogenesis, energy production and conversion, translation were differentially expressed. The vjbR mutant showed increased sensitivity to stresses of nutrition limitation, oxidative stress and acidification, and decreased survival in macrophage and mice, being consistent with its transcription profiles. These results indicated that the quorum sensing regulator vjbR could sense intracellular environments and response to them by regulate expression of virulence genes and other intracellular survival related genes, and therefore contribute to Brucella survival in host cells. This also provided direct evidence for the rational vaccine design by using antigenic global regulator for future development of genetically marked vaccine for brucellosis.
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Genome sequence of Brucella melitensis strain 128, an isolate of biovar 3 of sequence type 8.
J. Bacteriol.
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Brucella melitensis is the most common Brucella species causing human brucellosis. B. melitensis is divided into 3 biovars. Here, we report the complete genome sequence of B. melitensis strain 128, a strain of biovar 3 of sequence type 8, which is prevalent in China.
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