JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
An Anatomic Study to Determine the Optimal Entry Point, Medial Angles, and Effective Length for Safe Fixation using Posterior C1 Lateral Mass Screws.
Spine
PUBLISHED: 11-15-2014
Show Abstract
Hide Abstract
Study Design. Anatomic study of the C1 lateral mass using fine-cut computed tomographic (CT) scans and Mimics software.Objective. To investigate the optimal entry point, medial angles and effective length for safe fixation using posterior C1 lateral mass screws.Summary of Background Data. Placing posterior C1 lateral mass screws is technically demanding, and a misplaced screw can result in injury to the vertebral artery, spinal cord, or internal carotid artery. Although various insertion angles have been proposed for posterior C1 lateral mass screw, no clear consensus has been reached on the ideal medial angle of the C1 lateral mass.Methods. The C1 lateral masses were evaluated using CT scans and Mimics software in 70 patients. The effective width (EW) and effective screw length (ESL) of posterior C1 lateral mass screws were measured at different medial angulations relative to the midline sagittal plane. The height (H) for screw entry point on the posterior surface of C1 lateral mass and the distance (D) between screw entry point and the intersection of the midline sagittal plane and the posterior arch of the atlas were also measured.Results. The mean height (H) for screw entry on the posterior surface of the lateral mass was 4.25mm, the mean distance (D) between screw entry point and the intersection of the mid-sagittal plane and the posterior arch of the atlas was 27.62mm. The optimal medial angle was 20.86º with a corresponding effective width of 10.56mm and effective screw length of 21.87mm.Conclusion. This study helps to define the specific anatomy related to C1 posterior lateral mass screw placement in an effort to facilitate instrumentation. However, variation is seen in lateral mass anatomy, and this study must be combined with customized surgical planning that includes advanced imaging for safe and effective instrumentation.
Related JoVE Video
Lewis Base-Catalyzed Reaction of Aziridinofullerene with Ureas for the Preparation of Fulleroimidazolidinones.
J. Org. Chem.
PUBLISHED: 11-13-2014
Show Abstract
Hide Abstract
The Lewis base-catalyzed double nucleophilic substitution reaction of N-tosylaziridinofullerene with various ureas allows the easy preparation of fulleroimidazolidinones with a high tolerance for functional groups. The alkyl substituted ureas show better reactivity than aryl substituted ureas.
Related JoVE Video
Hypervalent Iodine Reagent Mediated Diamination of [60]Fullerene with Sulfamides or Phosphoryl Diamides.
Org. Lett.
PUBLISHED: 11-06-2014
Show Abstract
Hide Abstract
A hypervalent iodine-promoted intermolecular diamination reactions of C60 with sulfamides or phosphoryl diamides affords two classes of novel C60-fused cyclic sulfamide or phosphoryl diamide derivatives. The reaction between C60 and sulfamides can be effectively controlled to selectively synthesize diamination products or azafulleroids under PhIO/I2 or PhI(OAc)2/I2 conditions, respectively. Moreover, phosphoryl diamides were first used as an amine source in the diamination of alkenes.
Related JoVE Video
BF3·Et2O- or DMAP-Catalyzed Double Nucleophilic Substitution Reaction of Aziridinofullerenes with Sulfamides or Amidines.
J. Org. Chem.
PUBLISHED: 11-05-2014
Show Abstract
Hide Abstract
BF3·Et2O-catalyzed double nucleophilic substitution reaction of N-tosylaziridinofullerene with sulfamides has been exploited for the easy preparation of cyclic sulfamide-fused fullerene derivatives. Moreover, the Lewis base catalyzed double amination of N-tosylaziridinofullerene, with amidines as the diamine source, is demonstrated for the first time. The present methods provide new routes to cyclic 1,2-diaminated [60]fullerenes.
Related JoVE Video
The complete mitochondrial genomes of the Fenton's wood white, Leptidea morsei, and the lemon emigrant, Catopsilia pomona.
J. Insect Sci.
PUBLISHED: 11-05-2014
Show Abstract
Hide Abstract
The complete mitochondrial genomes of Leptidea morsei Fenton (Lepidoptera: Pieridae: Dis-morphiinae) and Catopsilia pomona (F.) (Lepidoptera: Pieridae: Coliadinae) were determined to be 15,122 and 15,142 bp in length, respectively, with that of L. morsei being the smallest among all known butterflies. Both mitogenomes contained 37 genes and an A+T-rich region, with the gene order identical to those of other butterflies, except for the presence of a tRNA-like insertion, tRNA(Leu) (UUR), in C. pomona. The nucleotide compositions of both genomes were higher in A and T (80.2% for L. morsei and 81.3% for C. pomona) than C and G; the A+T bias had a significant effect on the codon usage and the amino acid composition. The protein-coding genes utilized the standard mitochondrial start codon ATN, except the COI gene using CGA as the initiation codon, as reported in other butterflies. The intergenic spacer sequence between the tRNA(Ser) (UCN) and ND1 genes contained the ATACTAA motif. The A+T-rich region harbored a poly-T stretch and a conserved ATAGA motif located at the end of the region. In addition, there was a triplicated 23 bp repeat and a microsatellite-like (TA)9(AT)3 element in the A+T-rich region of the L. morsei mitogenome, while in C. pomona, there was a duplicated 24 bp repeat element and a microsatellite-like (TA)9 element. The phylogenetic trees of the main butterfly lineages (Hesperiidae, Papilionidae, Pieridae, Nymphalidae, Lycaenidae, and Riodinidae) were reconstructed with maximum likelihood and Bayesian inference methods based on the 13 concatenated nucleotide sequences of protein-coding genes, and both trees showed that the Pieridae family is sister to Lycaenidae. Although this result contradicts the traditional morphologically based views, it agrees with other recent studies based on mitochondrial genomic data.
Related JoVE Video
[Compensation method of broadband illuminant fluctuation based on spectrum linear fitting].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 11-01-2014
Show Abstract
Hide Abstract
The intensity of broadband illuminant fluctuates when its' power supply output power changes. Spectral intensities at each wavelength within the band of broadband illuminant fluctuate at different levels. A method based on spectrum linear fitting is proposed to compensate the illuminant spectral intensity in its band when its intensity fluctuates. The spectral intensity fluctuation at each wavelength could be compensated simply by measuring the band intensity with this method. The linear relationship between spectral radiant exitance and whole radiant exitance of ideal blackbody was analysed by researching the radiant exitance at different temperatures. The linear model of broadband illuminant band intensity and spectral intensity was built. Experimental system is composed of a halogen light, a power supply, an aperture, a spectrometer, and a computer mainly. By adjusting the power output of the power supply, we obtained a set of halogen light relative spectral intensities at different power inputs. The spectral intensity of halogen light at different input powers was measured to test the compensation effect of this method. The relationship between spectral intensity and band intensity of halogen light was fitted with linear relation and the fitting errors were analysed. The experimental result shows a linear relationship between spectral intensity and band intensity of halogen light, so the spectral intensity fluctuation can be compensated using the band intensity according to their linear relation. The relative error absolute value of compensated spectral intensity decreases as the halogen light input power increases. Within the range of halogen light input power, the relative error absolute values of spectral intensity compensated with this method are within 5% at vast majority (92%) of the wavelengths.
Related JoVE Video
Phylotranscriptomic analysis of the origin and early diversification of land plants.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 10-29-2014
Show Abstract
Hide Abstract
Reconstructing the origin and evolution of land plants and their algal relatives is a fundamental problem in plant phylogenetics, and is essential for understanding how critical adaptations arose, including the embryo, vascular tissue, seeds, and flowers. Despite advances in molecular systematics, some hypotheses of relationships remain weakly resolved. Inferring deep phylogenies with bouts of rapid diversification can be problematic; however, genome-scale data should significantly increase the number of informative characters for analyses. Recent phylogenomic reconstructions focused on the major divergences of plants have resulted in promising but inconsistent results. One limitation is sparse taxon sampling, likely resulting from the difficulty and cost of data generation. To address this limitation, transcriptome data for 92 streptophyte taxa were generated and analyzed along with 11 published plant genome sequences. Phylogenetic reconstructions were conducted using up to 852 nuclear genes and 1,701,170 aligned sites. Sixty-nine analyses were performed to test the robustness of phylogenetic inferences to permutations of the data matrix or to phylogenetic method, including supermatrix, supertree, and coalescent-based approaches, maximum-likelihood and Bayesian methods, partitioned and unpartitioned analyses, and amino acid versus DNA alignments. Among other results, we find robust support for a sister-group relationship between land plants and one group of streptophyte green algae, the Zygnematophyceae. Strong and robust support for a clade comprising liverworts and mosses is inconsistent with a widely accepted view of early land plant evolution, and suggests that phylogenetic hypotheses used to understand the evolution of fundamental plant traits should be reevaluated.
Related JoVE Video
Accurate estimation of haplotype frequency from pooled sequencing data and cost-effective identification of rare haplotype carriers by overlapping pool sequencing.
Bioinformatics
PUBLISHED: 10-09-2014
Show Abstract
Hide Abstract
A variety of hypotheses have been proposed for finding the missing heritability of complex diseases in genome-wide association studies. Studies have focused on the value of haplotype to improve the power of detecting associations with disease. To facilitate haplotype-based association analysis, it is necessary to accurately estimate haplotype frequencies of pooled samples.
Related JoVE Video
Structures, chemotaxonomic significance, cytotoxic and Na(+),K(+)-ATPase inhibitory activities of new cardenolides from Asclepias curassavica.
Org. Biomol. Chem.
PUBLISHED: 10-02-2014
Show Abstract
Hide Abstract
Five new cardenolide lactates () and one new dioxane double linked cardenolide glycoside () along with 15 known compounds ( and ) were isolated from the ornamental milkweed Asclepias curassavica. Their structures were elucidated by extensive spectroscopic methods (IR, UV, MS, 1D- and 2D-NMR). The molecular structures and absolute configurations of and were further confirmed by single-crystal X-ray diffraction analysis. Simultaneous isolation of dioxane double linked cardenolide glycosides () and cardenolide lactates () provided unique chemotaxonomic markers for this genus. Compounds were evaluated for the inhibitory activities against DU145 prostate cancer cells. The dioxane double linked cardenolide glycosides showed the most potent cytotoxic effect followed by normal cardenolides and cardenolide lactates, while the C21 steroids were non-cytotoxic. Enzymatic assay established a correlation between the cytotoxic effects in DU145 cancer cells and the Ki for the inhibition of Na(+),K(+)-ATPase. Molecular docking analysis revealed relatively strong H-bond interactions between the bottom of the binding cavity and compounds or , and explained why the dioxane double linked cardenolide glycosides possessed higher inhibitory potency on Na(+),K(+)-ATPase than the cardenolide lactate.
Related JoVE Video
Identifying the potential extracellular electron transfer pathways from a c-type cytochrome network.
Mol Biosyst
PUBLISHED: 09-18-2014
Show Abstract
Hide Abstract
Extracellular electron transfer (EET) is the key feature of some bacteria, such as Geobacter sulfurreducens and Shewanella oneidensis. Via EET processes, these bacteria can grow on electrode surfaces and make current output of microbial fuel cells. c-Type cytochromes can be used as carriers to transfer electrons, which play an important role in EET processes. Typically, from the inner (cytoplasmic) membrane through the periplasm to the outer membrane, they could form EET pathways. Recent studies suggest that a group of c-type cytochromes could form a network which extended the well-known EET pathways. We obtained the protein interaction information for all 41 c-type cytochromes in Shewanella oneidensis MR-1, constructed a large-scale protein interaction network, and studied its structural characteristics and functional significance. Centrality analysis has identified the top 10 key proteins of the network, and 7 of them are associated with electricity production in the bacteria, which suggests that the ability of Shewanella oneidensis MR-1 to produce electricity might be derived from the unique structure of the c-type cytochrome network. By modularity analysis, we obtained 5 modules from the network. The subcellular localization study has shown that the proteins in these modules all have diversiform cellular compartments, which reflects their potential to form EET pathways. In particular, combination of protein subcellular localization and operon analysis, the well-known and new candidate EET pathways are obtained from the Mtr-like module, indicating that potential EET pathways could be obtained from such a c-type cytochrome network.
Related JoVE Video
miRNA-646 suppresses osteosarcoma cell metastasis by downregulating fibroblast growth factor 2 (FGF2).
Tumour Biol.
PUBLISHED: 09-05-2014
Show Abstract
Hide Abstract
MicroRNAs are short regulatory RNAs that play crucial roles in cancer development and progression. MicroRNA-646 (miR-646) is downregulated in many human cancers, and increasing evidence indicates that it functions as a tumor suppressor. However, the role of miR-646 in osteosarcoma remains unclear. Expression levels of miR-646 in osteosarcoma cell lines and patient tissues were evaluated by quantitative real-time PCR (qRT-PCR), and the clinicopathological significance of the resultant data was later analyzed. Next, we investigated the role of miR-646 to determine its potential roles on osteosarcoma cell proliferation, migration, and invasion in vitro. A luciferase reporter assay was conducted to confirm the target gene of miR-646, and the results were validated in the osteosarcoma cell line. In this study, we found that miR-646 was downregulated in osteosarcoma cell lines and osteosarcoma tissues compared with normal osteoblast cell line NHOst and paired adjacent nontumor tissue. We found that a lower expression of miR-646 was associated with metastasis. In osteosarcoma cells, overexpression of miR-646 inhibited cell proliferation, migration, and invasion. In contrast, downregulation of miR-646 expression promoted osteosarcoma cell proliferation, migration, and invasion. Next, we identified that the FGF2 gene is a novel direct target of miR-646 in osteosarcoma cells. Moreover, enforced expression of FGF2 partially reversed the inhibition of cell proliferation, migration, and invasion that was caused by miR-646. Our study demonstrated that miR-646 might be a tumor suppressor in osteosarcoma via the regulation of FGF2, which provided a potential prognostic biomarker and therapeutic target.
Related JoVE Video
Regulation of miR-101/miR-199a-3p by the epithelial sodium channel during embryo implantation: involvement of CREB phosphorylation.
Reproduction
PUBLISHED: 09-03-2014
Show Abstract
Hide Abstract
In our previous study, we have demonstrated that the epithelial sodium channel (ENaC) mediates the embryo-derived signals leading to the activation of CREB and upregulation of cyclooxygenase type 2 (COX2) required for embryo implantation. This study aims to investigate whether microRNAs (miRNAs) are involved in the ENaC-induced upregulation of COX2 during embryo implantation. The results show that the levels of miR-101 and miR-199a-3p, two COX2 targeting miRNAs, are reduced by ENaC activation, and increased by ENaC inhibition or knock-down of ENaC subunit (ENaC?) in human endometrial surface epithelial (HES) cells or in mouse uteri during implantation. Phosphorylation of CREB is induced by the activation of ENaC, and blocked by ENaC inhibition or knockdown in HES cells. Knockdown of ENaC? or CREB in HES cells or in mouse uterus in vivo results in increases in miR-101 and miR-199a-3p, accompanied with decreases in COX2 protein levels and reduction in implantation rate. The downregulation of COX2 caused by knockdown of ENaC or CREB can be recovered by the inhibitors of miR-101 or miR-199a-3p in HES cells. These results reveal a novel molecular mechanism modulating COX2 expression during embryo implantation via ENaC-dependent CREB activation and COX2-targeting miRNAs.
Related JoVE Video
Construction of a host-independent T7 expression system with small RNA regulation.
J. Biotechnol.
PUBLISHED: 09-02-2014
Show Abstract
Hide Abstract
It is desirable to build a universal and efficient protein expression system for wild-type prokaryotic strains in biotechnology industry and the outstanding T7 expression system could be a good candidate. However, the current utilization of T7 system depends on the specific DE3 lysogenic hosts, which severely limits its application in wild-type strains. In this study, a host-independent T7 expression system without relying on DE3 lysogenic hosts to provide T7 RNA Polymerase was developed. T7 RNA Polymerase gene (Gene1) and T7 Promoter were successfully integrated into a single plasmid with the regulation of proper antisense RNA to limit T7 RNA Polymerase expression at a non-lethal level. This host-independent T7 expression system realized efficient protein expression in 4 non-DE3 Escherichia coli strains and a wild-type Sinorhizobium strain TH572.
Related JoVE Video
Telekin suppresses human hepatocellular carcinoma cells in vitro by inducing G2/M phase arrest via the p38 MAPK signaling pathway.
Acta Pharmacol. Sin.
PUBLISHED: 09-01-2014
Show Abstract
Hide Abstract
Telekin, isolated from the Chinese herb Carpesium divaricatum, has shown anti-proliferation effects against various cancer cells, including hepatocellular carcinoma cells. In this study, we investigated the anti-proliferation mechanisms of telekin in human hepatocellular carcinoma HepG2 cells in vitro.
Related JoVE Video
Robust method for infrared small-target detection based on Boolean map visual theory.
Appl Opt
PUBLISHED: 07-01-2014
Show Abstract
Hide Abstract
In this paper, we present an infrared small target detection method based on Boolean map visual theory. The scheme is inspired by the phenomenon that small targets can often attract human attention due to two characteristics: brightness and Gaussian-like shape in the local context area. Motivated by this observation, we perform the task under a visual attention framework with Boolean map theory, which reveals that an observer's visual awareness corresponds to one Boolean map via a selected feature at any given instant. Formally, the infrared image is separated into two feature channels, including a color channel with the original gray intensity map and an orientation channel with the orientation texture maps produced by a designed second order directional derivative filter. For each feature map, Boolean maps delineating targets are computed from hierarchical segmentations. Small targets are then extracted from the target enhanced map, which is obtained by fusing the weighted Boolean maps of the two channels. In experiments, a set of real infrared images covering typical backgrounds with sky, sea, and ground clutters are tested to verify the effectiveness of our method. The results demonstrate that it outperforms the state-of-the-art methods with good performance.
Related JoVE Video
650-nm 1 × 2 polymeric thermo-optic switch with low power consumption.
Opt Express
PUBLISHED: 06-13-2014
Show Abstract
Hide Abstract
In this paper, a low-power 1 × 2 polymeric thermo-optic switch operating at the polymer optical fiber low-loss window of 650 nm was studied. The characteristic parameters of the switch were carefully designed and simulated. The fabrication was done by using standard semiconductor fabrication techniques such as spin-coating, photolithography, and dry etching. The device was fabricated based on poly(methyl methacrylate) (PMMA)-based materials with the Mach-Zehnder interferometer (MZI) structure. The device shows an extinction ratio of over 23.4 dB at 650 nm with a very low-power consumption of 5.3 mW. The measured switching rise time and fall time are 464.4 and 448.0 µs, respectively.
Related JoVE Video
Nucleosome organization in the vicinity of transcription factor binding sites in the human genome.
BMC Genomics
PUBLISHED: 06-10-2014
Show Abstract
Hide Abstract
The binding of transcription factors (TFs) to specific DNA sequences is an initial and crucial step of transcription. In eukaryotes, this process is highly dependent on the local chromatin state, which can be modified by recruiting chromatin remodelers. However, previous studies have focused mainly on nucleosome occupancy around the TF binding sites (TFBSs) of a few specific TFs. Here, we investigated the nucleosome occupancy profiles around computationally inferred binding sites, based on 519 TF binding motifs, in human GM12878 and K562 cells.
Related JoVE Video
Quantitative group testing-based overlapping pool sequencing to identify rare variant carriers.
BMC Bioinformatics
PUBLISHED: 06-10-2014
Show Abstract
Hide Abstract
Genome-wide association studies have revealed that rare variants are responsible for a large portion of the heritability of some complex human diseases. This highlights the increasing importance of detecting and screening for rare variants. Although the massively parallel sequencing technologies have greatly reduced the cost of DNA sequencing, the identification of rare variant carriers by large-scale re-sequencing remains prohibitively expensive because of the huge challenge of constructing libraries for thousands of samples. Recently, several studies have reported that techniques from group testing theory and compressed sensing could help identify rare variant carriers in large-scale samples with few pooled sequencing experiments and a dramatically reduced cost.
Related JoVE Video
Electrophysiological responses of the rice leaffolder, Cnaphalocrocis medinalis, to rice plant volatiles.
J. Insect Sci.
PUBLISHED: 05-20-2014
Show Abstract
Hide Abstract
The rice leaffolder, Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae), is one of the most destructive pests of rice. Electrophysiological responses of this species to 38 synthetic volatiles known to be released from rice plants (Poaceae: Oryza spp.) were studied using the electroantennogram (EAG) method. Compounds that elicited the strongest EAG responses for each physiological condition were selected for EAG dose-response tests at five concentrations. These compounds included: methyl salicylate, heptanol, linalool, cyclohexanol, and 2-heptanone for one-day-old male moths; heptanol, hexanal, (Z)-2-hexen-1-ol, and nonadecane for one-day- old females; methyl salicylate, heptanol, (E)-2-hexen-1-ol, and (Z)-2-hexen-1-ol for three-day- old males; linalool, heptanol, (E)-2-hexen-1-ol, 2-heptanone, and hexanal for three-day-old females; 2-heptanone, cyclohexanol, linalool, heptanol, and methyl salicylate for five-day-old virgin females; and methyl benzoate, (Z)-2-hexen-1-ol, heptanol, linalool, and hexanal for five- day-old mated females. Female and male C. medinalis exhibited broad overlap in their EAG responses, and there was no clear difference between male and female EAG responses to different compounds. Statistical analyses revealed that both volatile compound chemical structure and C. medinalis physiological condition (age, sex, and mating condition) had an effect on EAG response.
Related JoVE Video
[Analysis of the complications of gynecological laparoscopic operation within 10 years].
Zhonghua Fu Chan Ke Za Zhi
PUBLISHED: 05-14-2014
Show Abstract
Hide Abstract
To investigate on the incidence of gynecological laparoscopic operation complications within ten years.
Related JoVE Video
Horizontal transfer of an adaptive chimeric photoreceptor from bryophytes to ferns.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-14-2014
Show Abstract
Hide Abstract
Ferns are well known for their shade-dwelling habits. Their ability to thrive under low-light conditions has been linked to the evolution of a novel chimeric photoreceptor--neochrome--that fuses red-sensing phytochrome and blue-sensing phototropin modules into a single gene, thereby optimizing phototropic responses. Despite being implicated in facilitating the diversification of modern ferns, the origin of neochrome has remained a mystery. We present evidence for neochrome in hornworts (a bryophyte lineage) and demonstrate that ferns acquired neochrome from hornworts via horizontal gene transfer (HGT). Fern neochromes are nested within hornwort neochromes in our large-scale phylogenetic reconstructions of phototropin and phytochrome gene families. Divergence date estimates further support the HGT hypothesis, with fern and hornwort neochromes diverging 179 Mya, long after the split between the two plant lineages (at least 400 Mya). By analyzing the draft genome of the hornwort Anthoceros punctatus, we also discovered a previously unidentified phototropin gene that likely represents the ancestral lineage of the neochrome phototropin module. Thus, a neochrome originating in hornworts was transferred horizontally to ferns, where it may have played a significant role in the diversification of modern ferns.
Related JoVE Video
Sequence-based predictor of ATP-binding residues using random forest and mRMR-IFS feature selection.
J. Theor. Biol.
PUBLISHED: 04-02-2014
Show Abstract
Hide Abstract
We develop a computational and statistical approach (ATPBR) for predicting ATP-binding residues in proteins from amino acid sequences by using random forests with a novel hybrid feature. The hybrid feature incorporates a new feature called PSSMPP, the predicted secondary structure and orthogonal binary vectors. The mRMR-IFS feature selection method is utilized to construct the best prediction model. At last, ATPBR achieves significantly improved performance over existing methods, with 87.53% accuracy and a Matthew?s correlation coefficient of 0.554. In addition, our further analysis demonstrates that PSSMPP distinguishes more effectively between ATP-binding and non-binding residues. Besides, the optimal features selected by the mRMR-IFS method improve the prediction performance and may provide useful insights for revealing the mechanisms of ATP and proteins interactions.
Related JoVE Video
Identification and functional characterization of the human ether-a-go-go-related gene Q738X mutant associated with hereditary long QT syndrome type 2.
Int. J. Mol. Med.
PUBLISHED: 03-07-2014
Show Abstract
Hide Abstract
QT interval prolongation, a risk factor for arrhythmias, may be associated with genetic variants in genes governing cardiac repolarization. Long QT syndrome type 2 (LQT2) is caused by mutations in the human ether-a-go?go-related gene (hERG). This gene encodes a voltage-gated potassium channel comprised of 4 subunits, and the formation of functional channels requires the proper assembly of these 4 subunits. In the present study, we investigated the role of the LQT2 mutation, Q738X, which causes truncation of the C-terminus of hERG channels, in the assembly and function of hERG channels. When expressed in HEK293 cells, Q738X did not generate an hERG current. The co-expression of Q738X with wild-type (WT)-hERG did not cause the dominant-negative suppression of the WT-hERG current. Western blot analysis and confocal microscopy revealed that the Q738X mutation caused defective trafficking of hERG channel proteins. Co-immunoprecipitation demonstrated that Q738X did not exhibit dominant-negative effects due to the failure of the mutant and WT subunits to co-assemble. In conclusion, the functional loss caused by the Q738X mutation in hERG K+ channels may be attributed to the disruption of tetrameric assembly.
Related JoVE Video
Volatiles Emitted from Tea Plants Infested by Ectropis obliqua Larvae Are Attractive to Conspecific Moths.
J. Chem. Ecol.
PUBLISHED: 03-04-2014
Show Abstract
Hide Abstract
Herbivore-induced plant volatiles have been reported to play a role in the host-searching behavior of herbivores. However, next to nothing is known about the effect of volatiles emitted from tea plants infested by Ectropis obliqua larvae on the behavior of conspecific adults. Here, we found that tea plants infested by E. obliqua caterpillars for 24 h were more attractive to both virgin male and female E. obliqua adults than were intact, uninfested tea plants; moreover, mated female E. obliqua moths were more attracted by infested tea plants and preferentially oviposited on these plants, whereas male moths were repelled by infested plants once they had mated. Volatile analysis revealed that the herbivore infestation dramatically increased the emission of volatiles. Among these volatiles, 17 compounds elicited antennal responses from both male and female virginal moths. Using a Y-tube olfactometer, we found that 3 of the 17 chemicals, benzyl alcohol, (Z)-3-hexenyl hexanoate, and (Z)-3-hexenal, were attractive, but two compounds, linalool and benzyl nitril, were repellent to virgin male and female moths. One chemical, (Z)-3-hexenyl acetate, was attractive only to virgin males. Mated females were attracted by three compounds, (Z)-3-hexenyl hexanoate, (Z)-3-hexenyl acetate, and (Z)-3-hexenal; whereas mated males were repelled by (Z)-3-hexenol. The findings provide new insights into the interaction between tea plants and the herbivores, and may help scientists develop new measures with which to control E. obliqua.
Related JoVE Video
2-[2-(4-Methyl-piperazin-1-yl)eth-yl]iso-indoline-1,3-dione.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 03-01-2014
Show Abstract
Hide Abstract
In the title compound, C15H19N3O2, the piperazine ring adopts a chair conformation, with its N-C bonds in pseudo-equatorial orientations. The dihedral angle between the C atoms of the piperazine ring and the phthalamide ring system (r.m.s. deviaiton = 0.008?Å) is 89.30?(8)°. In the crystal, mol-ecules are linked by C-H?O hydrogen bonds, generating a three-dimensional network and aromatic ?-? inter-actions also occur [centroid-centroid distances = 3.556?(1)-3.716?(1)?Å].
Related JoVE Video
Glucose-induced electrical activities and insulin secretion in pancreatic islet ?-cells are modulated by CFTR.
Nat Commun
PUBLISHED: 02-28-2014
Show Abstract
Hide Abstract
The cause of insulin insufficiency remains unknown in many diabetic cases. Up to 50% adult patients with cystic fibrosis (CF), a disease caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR), develop CF-related diabetes (CFRD) with most patients exhibiting insulin insufficiency. Here we show that CFTR is a regulator of glucose-dependent electrical acitivities and insulin secretion in ?-cells. We demonstrate that glucose elicited whole-cell currents, membrane depolarization, electrical bursts or action potentials, Ca(2+) oscillations and insulin secretion are abolished or reduced by inhibitors or knockdown of CFTR in primary mouse ?-cells or RINm5F ?-cell line, or significantly attenuated in CFTR mutant (DF508) mice compared with wild-type mice. VX-809, a newly discovered corrector of DF508 mutation, successfully rescues the defects in DF508 ?-cells. Our results reveal a role of CFTR in glucose-induced electrical activities and insulin secretion in ?-cells, shed light on the pathogenesis of CFRD and possibly other idiopathic diabetes, and present a potential treatment strategy.
Related JoVE Video
Intrinsic correlation of oligonucleotides: a novel genomic signature for metagenome analysis.
J. Theor. Biol.
PUBLISHED: 02-26-2014
Show Abstract
Hide Abstract
Because a vast majority (99%) of microbes in a given community is likely to be non-cultivable, metagenomics has gradually entered the mainstream of microbial research methods. With the development of high-throughput sequencing techniques, an increasing number of sequencing read data sets of metagenomes from various microbial communities have become available. For these data sets, metagenomic analysis based on mapping reads to microbial genomes has been hampered by the limited number of microbial genomes that are available. Further, this type of analysis is computationally intensive. Thus alignment-free methods, which characterize the sequencing reads with a genomic signature instead of with genomic alignments, can be applied. However, the main requirement of these alignment-free methods is a stable genomic signature that performs reliably. Here, we propose a novel genomic signature of microbial genomes called the intrinsic correlation of oligonucleotides (ICOs). This signature represents the quantification of an intrinsic relationship between any two oligonucleotides. We analyzed microbial genomes at different taxonomic levels using ICO profiles and confirmed the wide availability of useful ICOs. We used intra-genomic and inter-genomic distances and relational grades to evaluate the performance of ICOs as a genomic signature. The results of these experiments showed that ICOs can characterize microbial genomes well, and ICOs were better at distinguishing species than tetranucleotide composition, not only in terms of whole genomes but also in terms of sequence fragments. In addition, we evaluated the performance of a hybrid feature that combined ICOs and tetranucleotide composition. The experimental results showed that the hybrid feature performed better than ICOs or tetranucleotide composition alone. ICOs can characterize microbial genomes successfully and are capable of distinguishing organisms at different taxonomic levels. ICOs perform better than tetranucleotide composition in characterizing microbial genomes. The hybrid feature that used a combination of the two kinds of sequence features had advantages over a single sequence feature.
Related JoVE Video
The complete mitochondrial genome of Danaus chrysippus (Lepidoptera: Nymphalidae: Danainae).
Mitochondrial DNA
PUBLISHED: 01-14-2014
Show Abstract
Hide Abstract
Abstract The complete mitochondrial genome sequence of Danaus chrysippus (Lepidoptera: Nymphalidae: Danainae) was determined. The 15,236?bp long genome encodes 13 putative proteins, two ribosomal RNAs, 22 tRNAs and a non-coding AT-rich region. Its gene arrangement pattern is identical to most of other lepidopteran species. All protein-coding genes start with a typical ATN codon with the exception of COI gene which uses CGA as its initial codon; all PCGs terminate in the common stop TAA or TAG, except COI, COII, ND5 and ND4 which use single T as their stop codons. A total of 102?bp intergenic spacers and a total of 33?bp overlapping sequences are interspersed throughout the whole genome. The mitogenome harbors 22 txRNAs as those of most insect species and all tRNA genes evidence the typical clover leaf secondary structures with the exception of tRNA(ser) (AGN) who loses its dihydrouridine (DHU) arm. The lrRNA and srRNA genes are 1339 and 783?bp, with the AT contents of 84.1 and 84.8%, respectively. The non-coding AT-rich region is 418?bp long, and contains the motif ATAGA followed by a 21-bp poly-T stretch and a microsatellite-like (AT)9 element preceded by the ATTTA motif.
Related JoVE Video
Increased FAT10 expression is related to poor prognosis in pancreatic ductal adenocarcinoma.
Tumour Biol.
PUBLISHED: 01-10-2014
Show Abstract
Hide Abstract
It has been reported that FAT10 plays an important role in cell proliferation. Their activity is increased in malignant cells compared to benign cells. However, the clinical and functional significance of FAT10 expression has not been characterized previously in pancreatic ductal adenocarcinoma (PDAC). The purpose of this study was to assess FAT10 expression and to explore its contribution to PDAC. Real-time quantitative PCR was performed to examine FAT10 expression in 38 pairs of fresh frozen PDAC tissues and corresponding noncancerous tissues. Using immunohistochemistry, we performed a retrospective study of the FAT10 expression levels on 134 archival PDAC paraffin-embedded samples. The relationship between FAT10 mRNA expression and clinicopathological features was analyzed by appropriate statistics. Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between FAT10 expression and prognosis of PDAC patients. The relative mRNA expression of FAT10 was significantly higher in PDAC tissues than in adjacent noncancerous tissues (P<0.001). By immunohistochemistry, the data revealed that high FAT10 expression was significantly correlated with clinical stage (P<0.001), histological differentiation (P=0.004), and lymph node metastasis (P=0.013). Consistent with these results, we found that high expression of FAT10 was significantly correlated with poor survival in PDAC patients (P<0.001). Furthermore, Cox regression analyses showed that FAT10 expression was an independent predictor of overall survival. In conclusion, this study confirmed the overexpression of FAT10 and its association with tumor progression in PDAC. It also provided the first evidence that FAT10 expression in PDAC was an independent prognostic factor of patients, which might be a potential diagnostic and therapeutic target of PDAC.
Related JoVE Video
Short-term outcomes of minimally invasive Ivor-Lewis esophagectomy for esophageal cancer.
Ann. Thorac. Surg.
PUBLISHED: 01-09-2014
Show Abstract
Hide Abstract
Esophagectomy represents the gold standard in the treatment of resectable esophageal carcinoma. This retrospective study evaluated the significance of minimally invasive Ivor-Lewis esophagectomy (MIILE) for the treatment of esophageal carcinoma.
Related JoVE Video
Subregion-specific decreases in hippocampal serotonin transporter protein expression and function associated with endophenotypes of depression.
Hippocampus
PUBLISHED: 01-09-2014
Show Abstract
Hide Abstract
Stress influences the development of depression, and depression is associated with structural and functional changes in the hippocampus. The current study sought to determine whether chronic corticosteroid (CORT) treatment influences serotonin transporter (5-HTT) protein expression and function in the CA1, CA3, and dentate gyrus (DG) subregions of the hippocampus. Male CD-1 mice were subcutaneously injected with CORT at a dose of 20 mg/kg once daily for 3 weeks. Behavioral state was assessed using sucrose preference, physical state of the coat, forced swimming test, and tail suspension test. We then determine 5-HTT protein expression and synaptosomal 5-HT uptake in the CA1, CA3 and DG subregions. CORT treatment induced anhedonia and behavioral despair, two core endophenotypes of clinical depression; 5-HTT protein expression levels and synaptosomal 5-HT uptake were both decreased in a subregion-specific manner, with the greatest decrease observed in the DG, a moderate decrease in the CA3, and the CA1 showed no apparent change. In addition, a reduction in tissue mass was detected in the DG following the CORT treatment. These data indicate that subregion-specific decreases in hippocampal 5-HTT protein expression and function are associated with endophenotypes of depression.
Related JoVE Video
BF3·Et2O-catalyzed formal [3 + 2] reaction of aziridinofullerenes with carbonyl compounds.
J. Org. Chem.
PUBLISHED: 01-09-2014
Show Abstract
Hide Abstract
The BF3·Et2O-catalyzed formal [3 + 2] reaction of aziridinofullerenes with various carbonyl compounds for the easy preparation of fullerooxazolidines has been developed. Moreover, the reaction of aziridinofullerene with ethyl formate affords the simplest fullerooxazole without substituent.
Related JoVE Video
The effects of surface spin on magnetic properties of weak magnetic ZnLa0.02Fe1.98O4 nanoparticles.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
In order to prominently investigate the effects of the surface spin on the magnetic properties, the weak magnetic ZnLa0.02Fe1.98O4 nanoparticles were chosen as studying objects which benefit to reduce as possibly the effects of interparticle dipolar interaction and crystalline anisotropy energies. By annealing the undiluted and diluted ZnLa0.02Fe1.98O4 nanoparticles at different temperatures, we observed the rich variations of magnetic ordering states (superparamagnetism, weak ferromagnetism, and paramagnetism). The magnetic properties can be well understood by considering the effects of the surface spin of the magnetic nanoparticles. Our results indicate that in the nano-sized magnets with weak magnetism, the surface spin plays a crucial rule in the magnetic properties.
Related JoVE Video
Released micromachined beams utilizing laterally uniform porosity porous silicon.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Suspended micromachined porous silicon beams with laterally uniform porosity are reported, which have been fabricated using standard photolithography processes designed for compatibility with complementary metal-oxide-semiconductor (CMOS) processes. Anodization, annealing, reactive ion etching, repeated photolithography, lift off and electropolishing processes were used to release patterned porous silicon microbeams on a Si substrate. This is the first time that micromachined, suspended PS microbeams have been demonstrated with laterally uniform porosity, well-defined anchors and flat surfaces.
Related JoVE Video
[Retrieval of leaf area index of moso bamboo forest with Landsat Thematic Mapper image based on PROSAIL canopy radiative transfer model].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-31-2013
Show Abstract
Hide Abstract
The PROSAIL canopy radiative transfer model was used to establish leaf area index (LAI) and canopy reflectance lookup-table for Moso bamboo forest. The combination of Landsat Thematic Mapper (TM) image and this model was then used to retrieve LAI. The results demonstrated that the sensitivity of the input parameters in the PROSAIL model decreased in order of LAI >chlorophyll content (C(ab)) > leaf structure parameters (N) > mean leaf angle (ALA) > equivalent water thickness (C(w)) > dry matter content (C(m)). The most sensitive factors LAI and C(ab) were then used to construct the LAI-canopy reflectance lookup-table. The LAI estimates from the PROSAIL model had good agreement with the reference data, with the coefficient of determination (R2) reached 0.90. The root mean square error (RMSE) and relative RMSE were 0.58 and 13.0%, respectively. However, the mean LAI estimate was higher than the observed value.
Related JoVE Video
[Prevalence of nutritional risk among in-patients with liver diseases in Beijing, China].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 12-17-2013
Show Abstract
Hide Abstract
To investigate the prevalence of nutritional risk and malnutrition among in-patients with liver diseases in Beijing, China, and to evaluate the relationship between nutritional risk and prognosis.
Related JoVE Video
One-stage repair of extensive aortic aneurysms: mid-term results with total or subtotal aortic replacement.
Interact Cardiovasc Thorac Surg
PUBLISHED: 11-21-2013
Show Abstract
Hide Abstract
To retrospectively analyse the mid-term clinical results of one-stage repair of extensive aortic aneurysms with total or subtotal aortic replacement.
Related JoVE Video
Hypervalent iodine reagent mediated reaction of [60]fullerene with amines.
J. Org. Chem.
PUBLISHED: 11-21-2013
Show Abstract
Hide Abstract
The hypervalent iodine reagent mediated reaction of C60 with various readily available amines for the easy preparation of iminofullerenes has been developed. The reaction between C60 and sulfonamides can be effectively controlled to selectively synthesize azafulleroids or aziridinofullerenes under PhI(OAc)2/I2 or PhIO/I2/CuCl/lutidine conditions, respectively. For phosphamide and urea, only one isomer is obtained. However, carbamate gives three kinds of products. Interestingly, the reaction of C60 with alkylamines allows the effective synthesis of aziridinofullerenes and regioselective cis-1-bisaziridinofullerenes.
Related JoVE Video
CuCl2-Mediated Reaction of [60]Fullerene with Amines in the Presence or Absence of Dimethyl Acetylenedicarboxylate: Preparation of Fulleropyrroline or Aziridinofullerene Derivatives.
J. Org. Chem.
PUBLISHED: 11-08-2013
Show Abstract
Hide Abstract
The CuCl2-mediated three-component reaction of C60 with amines and dimethyl acetylenedicarboxylate afforded the fulleropyrrolines in moderate yields. Furthermore, the CuCl2-mediated oxidative [2 + 1] reaction of C60 with aromatic amines bearing a strong electron-withdrawing group provided the aziridinofullerenes and the selective cis-1-bisaziridinofullerenes.
Related JoVE Video
I2-catalyzed direct ?-hydroxylation of ?-dicarbonyl compounds with atmospheric oxygen under photoirradiation.
J. Org. Chem.
PUBLISHED: 10-31-2013
Show Abstract
Hide Abstract
An I2-catalyzed hydroxylation of ?-dicarbonyl moieties using air as the oxidant under photoirradiation has been developed for the easy preparation of ?-hydroxy-?-dicarbonyl compounds. The transformation was completed with only 1 mol % of I2. With ?-unsubstituted malonates, the hydroxylated dimerization product was afforded as the predominant product along with a minor product, ?,?-dihydroxyl malonate.
Related JoVE Video
The first mitochondrial genome for the butterfly family Riodinidae (Abisara fylloides) and its systematic implications.
Zool. Res.
PUBLISHED: 10-12-2013
Show Abstract
Hide Abstract
The Riodinidae is one of the lepidopteran butterfly families. This study describes the complete mitochondrial genome of the butterfly species Abisara fylloides, the first mitochondrial genome of the Riodinidae family. The results show that the entire mitochondrial genome of A. fylloides is 15 301 bp in length, and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and a 423 bp A+T-rich region. The gene content, orientation and order are identical to the majority of other lepidopteran insects. Phylogenetic reconstruction was conducted using the concatenated 13 protein-coding gene (PCG) sequences of 19 available butterfly species covering all the five butterfly families (Papilionidae, Nymphalidae, Peridae, Lycaenidae and Riodinidae). Both maximum likelihood and Bayesian inference analyses highly supported the monophyly of Lycaenidae+Riodinidae, which was standing as the sister of Nymphalidae. In addition, we propose that the riodinids be categorized into the family Lycaenidae as a subfamilial taxon.
Related JoVE Video
Association mapping of starch physicochemical properties with starch biosynthesizing genes in waxy rice (Oryza sativa L.).
J. Agric. Food Chem.
PUBLISHED: 10-09-2013
Show Abstract
Hide Abstract
Waxy (glutinous) rice is widely used in traditional foods, and understanding the genetic bases of its diverse physicochemical properties will contribute to breeding of new waxy rice with unique qualities. The objective of this study was to investigate the genetic relationship between the starch biosynthesis related genes and the physicochemical properties of waxy rice using association mapping. A total of 36 molecular markers representing 18 genes were used to genotype 50 waxy rice accessions for which starch properties were previously available. Most of the starch properties differed between high and low gelatinization temperature (GT) groups, whereas most traits were similar between the low-GT indica rice and low-GT japonica rice, suggesting GT was the main determinant of the starch quality of waxy rice. Association mapping indicated that the starch properties of waxy rice were mainly controlled by starch synthase IIa (SSIIa or SSII-3, a major gene responsible for the gelatinization temperature) and SSI. It was found that gene-gene interactions were also important for the genetic control of starch properties of waxy rice. This study suggests that application of the functional SNPs of SSIIa in molecular breeding may facilitate quality improvement of waxy rice.
Related JoVE Video
Nucleosome distribution near the 3 ends of genes in the human genome.
Biosci. Biotechnol. Biochem.
PUBLISHED: 10-07-2013
Show Abstract
Hide Abstract
By systematic analysis of high-throughput sequencing datasets from the human genome, we found that protein-coding genes have a specific chromatin structure near transcription termination sites relative to non-coding genes, one related to polyadenylation. Nucleosome was depleted near the site of cleavage/polyadenylation (polyA site) regardless of its relative position in the gene. DNA sequence plays an improtant role in nucleosome distribution, and conservative sequence elements and the protein binding to them are major determinants in causing nucleosome depletion near polyA sites. Furthermore, nucleosome occupancy was regulated by gene transcription and RNA polymerase II (RNAPII) occupancy. Our results reveal influences on nucleosome occupancy near polyadenylation sites and constitute evidence indicating that nucleosome distribution regulates 3 end processing of protein-coding genes.
Related JoVE Video
Reoperation on aortic disease in patients with previous aortic valve surgery.
Chin. Med. J.
PUBLISHED: 09-17-2013
Show Abstract
Hide Abstract
Aortic valve replacement (AVR) is a safe and effective method in the treatment of aortic valve diseases. This study aimed to increase the understanding on re-treatment of aortic diseases after aortic valve surgery through a retrospective analysis of 47 related cases.
Related JoVE Video
CuI-catalyzed oxidative [3 + 2] reaction of fullerene with amidines or amides using air as the oxidant: preparation of fulleroimidazole or fullerooxazole derivatives.
Org. Lett.
PUBLISHED: 09-04-2013
Show Abstract
Hide Abstract
CuI-catalyzed oxidative reaction of amidines with C60 using air as the oxidant has been exploited for the easy preparation of fulleroimidazole derivatives. Furthermore, this kind of CuI-catalyzed [3 + 2] reaction has also been successfully applied in the synthesis of fullerooxazole derivatives starting from amides for the first time. The substrate scope is broad, and the process is particularly cheap and simple.
Related JoVE Video
Blockage of hERG current and the disruption of trafficking as induced by roxithromycin.
Can. J. Physiol. Pharmacol.
PUBLISHED: 09-03-2013
Show Abstract
Hide Abstract
Roxithromycin is an oral macrolide antibiotic agent that has been repeatedly reported to provoke excessive prolongation of the Q-T interval and torsades de pointes in clinical settings. To investigate the mechanisms underlying the arrhythmogenic side effects of roxithromycin, we studied the molecular mechanisms of roxithromycin on human ether-à-go-go-related gene (hERG) K(+) channels expressed in human embryonic kidney (HEK293) cells. Roxithromycin was found to inhibit wild-type (WT) hERG currents in a concentration-dependent manner with a half-maximum block concentration (IC50) of 55.8 ± 9.1 ?mol/L. S6 residue hERG mutants (Y652A and F656C) showed reduced levels of hERG current blockage attributable to roxithromycin. Roxithromycin also inhibited the trafficking of hERG protein to the cell membrane, as confirmed by Western blot analysis and confocal microscopy. These findings indicate that roxithromycin may cause acquired long-QT syndrome via direct inhibition of hERG current and by disruption of hERG protein trafficking. Mutations in drug-binding sites (Y652A or F656C) of the hERG channel were found to attenuate hERG current blockage by roxithromycin, but did not significantly alter the disruption of trafficking.
Related JoVE Video
Comparison of Heidelberg retina tomography, optical coherence tomography and Humphrey visual field in early glaucoma diagnosis.
J. Int. Med. Res.
PUBLISHED: 09-03-2013
Show Abstract
Hide Abstract
To determine the value of optic disc parameters and perimetric defects in the early diagnosis of patients with primary open-angle glaucoma (POAG).
Related JoVE Video
[Scraping technique of stuck needle at Anmian point in the treatment of insomnia: a randomized controlled trial].
Zhongguo Zhen Jiu
PUBLISHED: 08-24-2013
Show Abstract
Hide Abstract
To compare the efficacy difference in the treatment of insomnia between scraping technique of stuck needle and conventional acupuncture at Anmian (Extra).
Related JoVE Video
Lysimachia clethroides Duby extract attenuates inflammatory response in Raw 264.7 macrophages stimulated with lipopolysaccharide and in acute lung injury mouse model.
J Ethnopharmacol
PUBLISHED: 08-13-2013
Show Abstract
Hide Abstract
Lysimachia clethroides Duby (LC) is a traditional medicinal herb used to treat edema, hepatitis and inflammatory diseases in China and other Asian countries. In this study, the anti-inflammatory effects of LC extract and the mechanisms underlying were explored in both in vitro cell lines and acute lung injury (ALI) animal model of inflammation in vivo.
Related JoVE Video
[Prospective multi-center study of one-step nucleic acid amplification assay for the detection of sentinel lymph nodes metastases in breast cancer patients].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-02-2013
Show Abstract
Hide Abstract
To evaluate the roles of Sysmex RD100i one-step nucleic acid amplification (OSNA) assay in the intraoperative assessments of breast cancer sentinel lymph nodes (SLNs).
Related JoVE Video
Taxifolin prevents diabetic cardiomyopathy in vivo and in vitro by inhibition of oxidative stress and cell apoptosis.
Food Chem. Toxicol.
PUBLISHED: 07-23-2013
Show Abstract
Hide Abstract
Diabetic cardiomyopathy has been increasingly recognized as an important cause of heart failure in diabetic patients. Excessive oxidative stress has been suggested to play a critical role in the development of diabetic cardiomyopathy. The objective of this study was to investigate the potential protective effects and mechanisms of taxifolin on cardiac function of streptozotocin-induced diabetic mice and on hyperglycemia-induced apoptosis of H9c2 cardiac myoblasts. In vivo study revealed that taxifolin improved diastolic dysfunction, ameliorated myocardium structure abnormality, inhibited myocyte apoptosis and enhanced endogenous antioxidant enzymes activities. Interestingly, taxifolin reduced angiotensin II level in myocardium, inhibited NADPH oxidase activity, and increased JAK/STAT3 activation. In vitro investigation demonstrated that taxifolin inhibited 33mM glucoseinduced H9c2 cells apoptosis by decreasing intracellular ROS level. It also inhibited caspase-3 and caspase-9 activation, restored mitochondrial membrane potential, and regulated the expression of proteins related to the intrinsic pathway of apoptosis, thus inhibiting the release of cytochrome c from mitochondria into the cytoplasm. In conclusion, taxifolin exerted cardioprotective effects against diabetic cardiomyopathy by inhibiting oxidative stress and cardiac myocyte apoptosis and might be a potential agent in the treatment of diabetic cardiomyopathy.
Related JoVE Video
Identification of novel microRNAs in primates by using the synteny information and small RNA deep sequencing data.
Int J Mol Sci
PUBLISHED: 07-16-2013
Show Abstract
Hide Abstract
Current technologies that are used for genome-wide microRNA (miRNA) prediction are mainly based on BLAST tool. They often produce a large number of false positives. Here, we describe an effective approach for identifying orthologous pre-miRNAs in several primates based on syntenic information. Some of them have been validated by small RNA high throughput sequencing data. This approach uses the synteny information and experimentally validated miRNAs of human, and incorporates currently available algorithms and tools to identify the pre-miRNAs in five other primates. First, we identified 929 potential pre-miRNAs in the marmoset in which miRNAs have not yet been reported. Then, we predicted the miRNAs in other primates, and we successfully re-identified most of the published miRNAs and found 721, 979, 650 and 639 new potential pre-miRNAs in chimpanzee, gorilla, orangutan and rhesus macaque, respectively. Furthermore, the miRNA transcriptome in the four primates have been re-analyzed and some novel predicted miRNAs have been supported by the small RNA sequencing data. Finally, we analyzed the potential functions of those validated miRNAs and explored the regulatory elements and transcription factors of some validated miRNA genes of interest. The results show that our approach can effectively identify novel miRNAs and some miRNAs that supported by small RNA sequencing data maybe play roles in the nervous system.
Related JoVE Video
Secular changes on the distribution of body mass index among Chinese children and adolescents, 1985-2010.
Biomed. Environ. Sci.
PUBLISHED: 06-18-2013
Show Abstract
Hide Abstract
To analyze the change in Body Mass Index (BMI) distribution among Chinese children and adolescents for the development of more effective intervention for childhood obesity.
Related JoVE Video
NF-?B activation was involved in reactive oxygen species-mediated apoptosis and autophagy in 1-oxoeudesm-11(13)-eno-12,8?-lactone-treated human lung cancer cells.
Arch. Pharm. Res.
PUBLISHED: 06-09-2013
Show Abstract
Hide Abstract
1-oxoeudesm-11(13)-eno-12,8?-lactone (OEL), a novel eudesmane-type sesquiterpene compound, has been shown to inhibit the growth of some cancer cell lines and induce significant apoptosis. Here, we investigated the anti-cancer activities of OEL in human lung cancer cells. Our studies demonstrated that OEL induced both apoptosis and autophagy in A549 and H460 cells. OEL-induced autophagy was assessed by appearance of autophagic vacuoles, formation of acidic vesicular organelles, conversion of LC3-I to LC3-II, recruitment of LC3-II to the autophagosomes, and activation of autophagy genes. Furthermore, administration of autophagic inhibitor 3-methyladenine augments OEL-induced apoptotic cell death. The induction of autophagy and apoptosis by OEL links to NF-?B activation and the generation of reactive oxygen species (ROS). Interruption of NF-?B activation by specific inhibitor promotes apoptosis, but decreases autophagy. ROS antioxidants (N-acetylcysteine) attenuated both OEL-induced autophagy and apoptosis. Further experiments confirmed that OEL-induced activation of ROS was increased by NF-?B inhibitor whereas NF-?B activation was not affected by ROS inhibition. These findings suggest that OEL-elicited autophagic response plays a protective role that impedes cell death, and inhibition of autophagy could be an adjunctive strategy for enhancing the chemotherapeutic effect of OEL as an antitumor agent.
Related JoVE Video
[Research on pattern search method for inversion of particle size distribution in spectral extinction technique].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 05-28-2013
Show Abstract
Hide Abstract
Development of rapid and efficient inversion methods for retrieval of particle size distribution (PSD) is an important subject of research effort. The main intention of the present paper is to develop pattern search method combined with Tikhonov smoothing functional for the determination of un-parameterized shape-independent PSD in spectral extinction technique. To ensure a good rapidity and accuracy of the whole search process, a competitive strategy was also designed. The inversion results for standard spherical polystyrene samples using the proposed method show that the relative error for volume mean diameter is 3.14% which does not exceed the range of +/- 8% specified by the National Bureau of Standard Reference Material of China. Moreover, the breadth of the inversed PSD is satisfied and there are not obvious artifact peaks. When compared with Phillips-Twomey method and genetic algorithm, the modified pattern search method has advantages concerning the inversion precision and inversion time, which makes the proposed method more suitable for quick and accurate measurement of particle sizing.
Related JoVE Video
SLC26 anion exchangers in uterine epithelial cells and spermatozoa: clues from the past and hints to the future.
Cell Biol. Int.
PUBLISHED: 05-24-2013
Show Abstract
Hide Abstract
The solute carrier 26 (SLC26) family emerges as a distinct class of anion transporters with its members SLC26A3 (Slc26a3) and SLC26A6 (Slc26a6) reported to be electrogenic Cl(-) /HCO3 (-) exchangers. While it is known that uterine fluid has high HCO3 (-) content and that HCO3 (-) is essential for sperm capacitation, the molecular mechanisms underlying the transport of HCO3 (-) across uterine epithelial cells and sperm have not been fully investigated. The present review re-examines the results from early reports studying anion transport, finding clues for the involvement of Cl(-) /HCO3 (-) anion exchangers in electrogenic HCO3 (-) transport across endometrial epithelium. We also summarise recent work on Slc26a3 and Slc26a6 in uterine epithelial cells and sperm, revealing their functional role in working closely with the cystic fibrosis transmembrane conductance regulator (CFTR) for HCO3 (-) transport in these cells. The possible involvement of these anion exchangers in other HCO3 (-) dependent reproductive processes and their implications for infertility are also discussed.
Related JoVE Video
[Magnetic resonance imaging of children with fecal incontinence after anoplasty for anorectal malformation and its clinical significance].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 05-23-2013
Show Abstract
Hide Abstract
To study the development of pelvic floor muscle, morphology and location of rectum and anal canal as well as morphology of spinal cord and sacrum based on pelvic magnetic resonance imaging(MRI) of children with fecal incontinence after anoplasty for anorectal malformation and to provide information on management of fecal incontinence.
Related JoVE Video
Single nucleotide polymorphisms in the NER pathway and clinical outcome of patients with bone malignant tumors.
Asian Pac. J. Cancer Prev.
PUBLISHED: 05-18-2013
Show Abstract
Hide Abstract
The effects of polymorphisms in ERCC5, ERCC6, XPC, CCNH and MMS19L on osteosarcoma response to chemotherapy and the survival of the affected patients were assessed. Genotyping of ERCC5, ERCC6, XPC, CCNH and MMS19L was performed by PCR-RFLP assay. The median PFS was 12.8 months, and the median OS was 18.6 months. Individuals carrying homozygous genotypes of ERCC5 rs17655 and ERCC5 rs1047768 were more like to have good response to treatment, while those carrying homozygous genotypes of MMS19L rs29001322 showed poor response. Osteosarcoma patients carrying TT genotype of ERCC5 rs1047768 showed a significantly longer PFS (16.8 months) and OS (21.4 months) than CC genotype, with HRs(95% CI) of 0.31 (0.10-0.93) and 0.32 (0.06-0.97), respectively. Conversely, those with the TT genotype of MMS19L rs29001322 demonstrated shorter PFS and OS, the HRs (95% CI) being 2.23 (1.08-4.15) and 4.62 (1.45-16.08), respectively. Our findings showed polymorphisms in ERCC5 rs1047768 and MMS19L rs29001322 to be associated with clinical outcome of osteosarcoma patients undergoing chemotherapy.
Related JoVE Video
Emodin attenuates A23187-induced mast cell degranulation and tumor necrosis factor-? secretion through protein kinase C and I?B kinase 2 signaling.
Eur. J. Pharmacol.
PUBLISHED: 05-16-2013
Show Abstract
Hide Abstract
Mast cells are known to play a pivotal role in allergic diseases. Cross-linking of the high-affinity IgE receptor (Fc?RI) is known to be one of the major causes that lead to degranulation and allergic inflammation. An increase in intracellular calcium (Ca(2+)) concentration also triggers degranulation, bypassing receptor activation. Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is known to exhibit a variety of pharmacological activities including anti-allergic effects. However, the detailed molecular mechanisms involved in exhibiting anti-allergic effects by emodin were remained to be clarified. In the present investigation we report the regulatory function of emodin on the allergic signal mediators through Ca(2+) ionophore activation in mast cells. Emodin significantly inhibited A23187-induced tumor necrosis factor-? production and degranulation through the attenuation of protein kinase C, I?B kinase 2, and soluble N-ethylmaleimide-sensitive fusion factor attachment protein receptor complex formation, bypassing Fc?RI activation. Data from our study indicated that emodin acts by regulating multiple signaling pathways in inhibiting the allergic reactions in mast cells.
Related JoVE Video
The nucleosome regulates the usage of polyadenylation sites in the human genome.
BMC Genomics
PUBLISHED: 04-27-2013
Show Abstract
Hide Abstract
It has been reported that 3[prime] end processing is coupled to transcription and nucleosome depletion near the polyadenylation sites in many species. However, the association between nucleosome occupancy and polyadenylation site usage is still unclear.
Related JoVE Video
Expression of integrin ?3 and osteopontin in the eutopic endometrium of adenomyosis during the implantation window.
Eur. J. Obstet. Gynecol. Reprod. Biol.
PUBLISHED: 04-26-2013
Show Abstract
Hide Abstract
To investigate the expression of integrin ?3 and osteopontin (OPN) in the eutopic endometrium of adenomyosis and to characterize possible endometrial defects in adenomyosis.
Related JoVE Video
Identifying rare variants with optimal depth of coverage and cost-effective overlapping pool sequencing.
Genet. Epidemiol.
PUBLISHED: 04-23-2013
Show Abstract
Hide Abstract
Genome-wide association studies have identified hundreds of genetic variants associated with complex diseases although most variants identified so far explain only a small proportion of heritability, suggesting that rare variants are responsible for missing heritability. Identification of rare variants through large-scale resequencing becomes increasing important but still prohibitively expensive despite the rapid decline in the sequencing costs. Nevertheless, group testing based overlapping pool sequencing in which pooled rather than individual samples are sequenced will greatly reduces the efforts of sample preparation as well as the costs to screen for rare variants. Here, we proposed an overlapping pool sequencing to screen rare variants with optimal sequencing depth and a corresponding cost model. We formulated a model to compute the optimal depth for sufficient observations of variants in pooled sequencing. Utilizing shifted transversal design algorithm, appropriate parameters for overlapping pool sequencing could be selected to minimize cost and guarantee accuracy. Due to the mixing constraint and high depth for pooled sequencing, results showed that it was more cost-effective to divide a large population into smaller blocks which were tested using optimized strategies independently. Finally, we conducted an experiment to screen variant carriers with frequency equaled 1%. With simulated pools and publicly available human exome sequencing data, the experiment achieved 99.93% accuracy. Utilizing overlapping pool sequencing, the cost for screening variant carriers with frequency equaled 1% in 200 diploid individuals dropped to at least 66% at which target sequencing region was set to 30 Mb.
Related JoVE Video
Regurgitant derived from the tea geometrid Ectropis obliqua suppresses wound-induced polyphenol oxidases activity in tea plants.
J. Chem. Ecol.
PUBLISHED: 04-23-2013
Show Abstract
Hide Abstract
Polyphenol oxidases (PPOs) have been reported to play an important role in protecting plants from attack by herbivores. However, little is known about their role in tea. Here, we investigated the effect of PPOs on interactions between tea plants and the tea geometrid Ectropis obliqua, one of the most important insect pests of tea. Jasmonic acid (JA) treatment resulted in increases in PPO activity, and the effect of JA was dose dependent. Ectropis obliqua caterpillars grew and developed more slowly on JA-treated tea plants than on control plants, and larval weight gains depended on the JA dosage. Artificial diet complemented with PPOs reduced the growth and survival rate of E. obliqua caterpillars, and there was a negative relationship between PPO level and larval growth and survival. Unlike mechanical wounding, which is an effective inducer of tea plant PPO activity, wounding plus the herbivore regurgitant or herbivore infestation suppressed the wound-induced PPO activities, especially at 4 days after treatment. These results suggest that PPOs are an important anti-herbivore factor in tea plants, defending them against E. obliqua larvae, and that E. obliqua larvae have evolved to elude the tea plants defense by inhibiting the production of PPOs.
Related JoVE Video
Highly stereoselective, one-pot synthesis of azetidines and 2,4-dioxo-1,3-diazabicyclo[3.2.0] compounds mediated by I2.
J. Org. Chem.
PUBLISHED: 04-19-2013
Show Abstract
Hide Abstract
We report here a convenient method to construct polysubstituted azetidines and 2,4-dioxo-1,3-diazabicyclo[3.2.0] compounds with high stereoselectivities in a one-pot reaction mediated by I2. The tetramethylguanidine (TMG)/I2-mediated formal [2 + 2] cycloaddition reaction of ?-amidomalonate 1 with enones 2 affords functionalized azetidine derivatives 4 in moderate to good yields with high diastereoselectivity. When the ?-ureidomalonate 5 is used instead of 1, 2,4-dioxo-1,3-diazabicyclo[3.2.0]heptanes 8 and 2,4-dioxo-1,3-diazabicyclo[3.2.0]heptenes 9 can be prepared selectively through the control of solvent and temperature. 2,4-Dioxo-1,3-diazabicyclo[3.2.0]heptanes 8 can further undergo ring-opening reactions with different nucleophilic reagents to afford the corresponding polyfunctionalized azetidine derivatives 13-16 with high steroselectivities.
Related JoVE Video
Prioritization of disease susceptibility genes using LSM/SVD.
IEEE Trans Biomed Eng
PUBLISHED: 04-18-2013
Show Abstract
Hide Abstract
Understanding the role of genetics in diseases is one of the most important tasks in the post-genome era. It is generally too expensive and time-consuming to perform experimental validation for all candidate genes related to disease. Computational methods play important roles for prioritizing these candidates. Herein, we propose an approach to prioritize disease genes using latent semantic mapping (LSM) based on singular value decomposition (SVD). Our hypothesis is that similar functional genes are likely to cause similar diseases. Measuring the functional similarity between known disease susceptibility genes and unknown genes is to predict new disease susceptibility genes. Taking autism as an instance, the analysis results of the top 10 genes prioritized demonstrate they might be autism susceptibility genes, which also indicates our approach could discover new disease susceptibility genes. The novel approach of disease gene prioritization could discover new disease susceptibility genes, and latent disease-gene relations. The prioritized results could also support the interpretive diversity and experimental views as computational evidence for disease researchers.
Related JoVE Video
Diabetes-induced central neuritic dystrophy and cognitive deficits are associated with the formation of oligomeric reticulon-3 via oxidative stress.
J. Biol. Chem.
PUBLISHED: 04-16-2013
Show Abstract
Hide Abstract
Diabetes is a high risk factor to dementia. To investigate the molecular mechanism of diabetic dementia, we induced type 2 diabetes in rats and examined potential changes in their cognitive functions and the neural morphology of the brains. We found that the diabetic rats with an impairment of spatial learning and memory showed the occurrence of RTN3-immunoreactive dystrophic neurites in the cortex. Biochemical examinations revealed the increase of a high molecular weight form of RTN3 (HW-RTN3) in diabetic brains. The corresponding decrease of monomeric RTN3 was correlated with the reduction of its inhibitory effects on the activity of ?-secretase (BACE1), a key enzyme for generation of ?-amyloid peptides. The results from immunoprecipitation combined with protein carbonyl detection showed that carbonylated RTN3 was significantly higher in cortical tissues of diabetic rats compared with control rats, indicating that diabetes-induced oxidative stress led to RTN3 oxidative damage. In neuroblastoma SH-SY5Y cells, high glucose and/or H2O2 treatment significantly increased the amounts of carbonylated proteins and HW-RTN3, whereas monomeric RTN3 was reduced. Hence, we conclude that diabetes-induced cognitive deficits and central neuritic dystrophy are correlated with the formation of aggregated RTN3 via oxidative stress. We provided the first evidence that oxidative damage caused the formation of toxic RTN3 aggregates, which participated in the pathogenesis of central neuritic dystrophy in diabetic brain. Present findings may offer a new therapeutic strategy to prevent or reduce diabetic dementia.
Related JoVE Video
Design, characterization, and in vitro cellular inhibition and uptake of optimized genistein-loaded NLC for the prevention of posterior capsular opacification using response surface methodology.
Int J Pharm
PUBLISHED: 03-21-2013
Show Abstract
Hide Abstract
This study was to design an innovative nanostructured lipid carrier (NLC) for drug delivery of genistein applied after cataract surgery for the prevention of posterior capsular opacification. NLC loaded with genistein (GEN-NLC) was produced with Compritol 888 ATO, Gelucire 44/14 and Miglyol 812N, stabilized by Solutol(®) HS15 by melt emulsification method. A 2(4) central composite design of 4 independent variables was performed for optimization. Effects of drug concentration, Gelucire 44/14 concentration in total solid lipid, liquid lipid concentration, and surfactant concentration on the mean particle size, polydispersity index, zeta potential and encapsulation efficiency were investigated. Analysis of variance (ANOVA) statistical test was used to assess the optimization. The optimized GEN-NLC showed a homogeneous particle size of 90.16 nm (with PI=0.33) of negatively charged surface (-25.08 mv) and high encapsulation efficiency (91.14%). Particle morphology assessed by TEM revealed a spherical shape. DSC analyses confirmed that GEN was mostly entrapped in amorphous state. In vitro release experiments indicated a prolonged and controlled genistein release for 72 h. In vitro growth inhibition assay showed an effective growth inhibition of GEN-NLCs on human lens epithelial cells (HLECs). Preliminary cellular uptake test proved a enhanced penetration of genistein into HLECs when delivered in NLC.
Related JoVE Video
The complete mitochondrial genome of Hebomoia glaucippe (Lepidoptera: Pieridae).
Mitochondrial DNA
PUBLISHED: 03-14-2013
Show Abstract
Hide Abstract
The mitochondrial genome of Hebomoia glaucippe (Lepidoptera: Pieridae) is a circular molecule of 15,701 bp in length, containing 37 typical mitochondrial genes and an AT-rich region. Its gene arrangement pattern is identical with those of other butterfly species. All protein-coding genes start with ATN start codon except for the cox1 gene, which uses CGA as the initiation codon. A total of 109 bp intergenic spacers and a total of 38 bp overlapping sequences are interspersed throughout the whole genome. The 899-bp long AT-rich region is the second longest among the completely sequenced lepidopteran insects, and contains the motif ATAGA followed by an 19-bp poly-T stretch, two microsatellite-like (AT)(10) elements, a duplicated 271-bp repeat element, and two extra tRNA(Leu)(UUR)-like genes.
Related JoVE Video

What is Visualize?

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

How does it work?

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

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

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