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Find video protocols related to scientific articles indexed in Pubmed.
Extreme Synergistic Mutational Effects in the Directed Evolution of a Baeyer-Villiger Monooxygenase as Catalyst for Asymmetric Sulfoxidation.
J. Am. Chem. Soc.
PUBLISHED: 11-15-2014
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Structure-based directed evolution utilizing iterative saturation mutagenesis (ISM) has been applied to phenyl acetone monooxygenase (PAMO), a thermally robust Baeyer-Villiger monooxygenase, in the quest to access a mutant which displays reversed enantioselectivity in the asymmetric sulfoxidation of prochiral thioethers. Whereas WT PAMO leads to 90% ee in the sulfoxidation of p-methylbenzyl methyl thioether with preference for the (S)-sulfoxide, the evolved mutant I67Q/P440F/A442N/L443I is 95% (R)-selective in the reaction of this and in other thioethers. Partial deconvolution of the (R)-selective mutant with generation of the respective four single mutants shows that all of them are (S)-selective, which points to pronounced synergism (cooperative non-additivity) when they interact in concert. Complete deconvolution with formation of all combinatorial forms of the respective double and triple mutants allows the designed construction of a fitness landscape featuring all 24 upward pathways leading from WT to the (R)-selective quadruple mutant. In all 24 trajectories strong cooperative mutational effects were found as well, which indicates that such mutational changes in enzymes constitute non-linear systems. A theoretical analysis based on induced fit docking explains many of the observed effects on a molecular level.
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Confined surface plasmon sensors based on strongly coupled disk-in-volcano arrays.
Nanoscale
PUBLISHED: 11-12-2014
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Disk-in-volcano arrays are reported to greatly enhance the sensing performance due to strong coupling in the nanogaps between the nanovolcanos and nanodisks. The designed structure, which is composed of a nanovolcano array film and a disk in each cavity, is fabricated by a simple and efficient colloidal lithography method. By tuning structural parameters, the disk-in-volcano arrays show greatly enhanced resonances in the nanogaps formed by the disks and the inner wall of the volcanos. Therefore they respond to the surrounding environment with a sensitivity as high as 977 nm per RIU and with excellent linear dependence on the refraction index. Moreover, through mastering the fabrication process, biological sensing can be easily confined to the cavities of the nanovolcanos. The local responsivity has the advantages of maximum surface plasmon energy density in the nanogaps, reducing the sensing background and saving expensive reagents. The disk-in-volcano arrays also possess great potential in applications of optical and electrical trapping and single-molecule analysis, because they enable establishment of electric fields across the gaps.
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Violation of the 12/23 rule of genomic V(D)J recombination is common in lymphocytes.
Genome Res.
PUBLISHED: 11-03-2014
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V(D)J genomic recombination joins single gene segments to encode an extensive repertoire of antigen receptor specificities in T and B lymphocytes. This process initiates with double-stranded breaks adjacent to conserved recombination signal sequences that contain either 12 or 23 nucleotide spacer regions. Only recombination between signal sequences with unequal spacers result in productive coding genes, a phenomenon known as the '12/23 rule'. Here we present two novel genomic tools that allow the capture and analysis of immune locus rearrangements from whole thymic and splenic tissues using second generation sequencing. Further, we provide strong evidence that the 12/23 rule of genomic recombination is frequently violated under physiological conditions resulting in unanticipated hybrid recombinations in ~10% of Tcra excision circles. Hence, we demonstrate that strict adherence to the 12/23 rule is intrinsic neither to recombination signal sequences nor to the catalytic process of recombination and propose that non-classical excision circles are liberated during the formation of antigen receptor diversity.
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MOFs synthesized by the ionothermal method addressing the leaching problem of IL-polymer composite membranes.
Chem. Commun. (Camb.)
PUBLISHED: 10-02-2014
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The liquid nature of ionic liquids (ILs) limits their use in potential electrolytes due to the problem of leakage. Herein, we design a new strategy to immobilize an ionic liquid by incorporating it within ZIF-8 (ZIF = zeolitic imidazolate framework) by the ionothermal method.
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Isolation and differential expression of a novel MAP kinase gene DoMPK4 in Dendrobium officinale.
Yao Xue Xue Bao
PUBLISHED: 09-20-2014
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Mitogen-activated protein kinases (MAPKs) are important signaling transduction components well conserved in eukaryotes and play essential roles in various physiological, developmental and hormonal responses in plant. In the present study, a MAPK gene, designated as DoMPK4 (GenBank accession No. JX297597), is identified from a rare endangered medicinal orchid species D. officinale using the reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods. The full length cDNA of DoMPK4 is 1 518 bp in length and encoded a 369 aa protein with a molecular weight of 42.42 kD and an isoelectric point of 5.55. DoMPK4 protein contained a serine/threonine protein kinase active site (158-170), a MAP kinase site (71-174), and eight conserved motifs. DoMPK4 had a transmembrane (214-232) but no signal peptide. Multiple sequence alignment showed that DoMPK4 shared high identities (74.9%-80.6%) with MAPK proteins from various plants. Phylogenetic analysis demonstrated that DoMPK4 belonged to group A of the MAPK evolutionary tree, and is closely related to monocots. Real time quantitative PCR (qPCR) analysis revealed that DoMPK4 is differentially expressed among the five organs including leaf, stem, root, seed, and protocorm-like body (PLB). The transcription level of DoMPK4 is the highest in the PLBs with 17.65 fold, followed by seeds, roots, and stems with 5.84, 2.28, and 1.64 fold, respectively. The progressive enhancement of DoMPK4 transcripts in the developing PLBs compared to that in the germinating seeds, suggests a role of DoMPK4 during the development of embryogenic PLBs formation in D. officinale.
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Extraordinary photoluminescence and strong temperature/angle-dependent Raman responses in few-layer phosphorene.
ACS Nano
PUBLISHED: 09-08-2014
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Phosphorene is a new family member of two-dimensional materials. We observed strong and highly layer-dependent photoluminescence in few-layer phosphorene (two to five layers). The results confirmed the theoretical prediction that few-layer phosphorene has a direct and layer-sensitive band gap. We also demonstrated that few-layer phosphorene is more sensitive to temperature modulation than graphene and MoS2 in Raman scattering. The anisotropic Raman response in few-layer phosphorene has enabled us to use an optical method to quickly determine the crystalline orientation without tunneling electron microscopy or scanning tunneling microscopy. Our results provide much needed experimental information about the band structures and exciton nature in few-layer phosphorene.
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[Screening and confirmation of 24 hormones in cosmetics by ultra high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry].
Se Pu
PUBLISHED: 09-05-2014
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A method of ultra high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (UPLC-LTQ/Orbitrap MS) was established to screen and confirm 24 hormones in cosmetics. Various cosmetic samples were extracted with methanol. The extract was loaded onto a Waters ACQUITY UPLC BEH C18 column (50 mm x 2.1 mm, 1.7 microm) using a gradient elution of acetonitrile/water containing 0.1% (v/v) formic acid for the separation. The accurate mass of quasi-molecular ion was acquired by full scanning of electrostatic field orbitrap. The rapid screening was carried out by the accurate mass of quasi-molecular ion. The confirmation analysis for targeted compounds was performed with the retention time and qualitative fragments obtained by data dependent scan mode. Under the optimal conditions, the 24 hormones were routinely detected with mass accuracy error below 3 x 10(-6) (3 ppm), and good linearities were obtained in their respective linear ranges with correlation coefficients higher than 0.99. The LODs (S/N = 3) of the 24 compounds were < or = 10 microg/kg, which can meet the requirements for the actual screening of cosmetic samples. The developed method was applied to screen the hormones in 50 cosmetic samples. The results demonstrate that the method is a useful tool for the rapid screening and identification of the hormones in cosmetics.
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Induction of human chronic myeloid leukemia K562 cell apoptosis by virosecurinine and its molecular mechanism.
Mol Med Rep
PUBLISHED: 09-03-2014
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Virosecurinine is a major alkaloid of the plant Securinega suffruticosa and has been found to be a potent agent in inducing the differentiation of cancer cells. The present study aimed to investigate the antitumor effects of virosecurinine by inducing the apoptosis of leukemic K562 cells and to examine the underlying mechanisms. K562 cells were treated with different concentrations of virosecurinine (6.25, 12.5, 25, 50, 100 and 200 µmol/l) for 24, 48 and 72 h. The cell counting kit (CCK)?8 method was used to detect the antitumor effect of K562 cells in vitro. Flow cytometry was used to observe the apoptotic ratio and analyze the cell cycle following treatment with virosecurinine in K562 cells. Light and electron microscopy was used to identify morphological alterations in the virosecurinine?treated K562 cells. The mRNA levels of mammalian target of rapamycin (mTOR), SH2 domain?containing inositol?5'?phosphatase 2 (SHIP2), phosphatase and tensin homologue (PTEN) and breakpoint cluster region (BCR)/Abelson (ABL) were detected pre and post?virosecurinine treatment using reverse transcription quantitative polymerase chain reaction (RT?qPCR). The generation depression effects of K562 cells cultured in vitro were detected using CCK?8 technology, which revealed a dose and time?dependent association. The IC50 was 32.984 µmol/l at 48 h. Flow cytometric analysis indicated that treatment with virosecurinine at concentrations of 6.25, 25 and 50 µmol/l increased the apoptotic rate of the K562 cells and caused G1/S phase arrest. RT?qPCR indicated that virosecurinine upregulated the gene expression of PTEN and downregulated the expression of mTOR, SHIP?2 and BCR/ABL in K562 cells. Virosecurinine inhibited the growth and proliferation of the K562 cell lines and induced apoptosis in K562 cells by affecting the expression of mTOR, SHIP2, BCR/ABL and PTEN.
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Real-time control of uni-directional liquid spreading on a half-cone nanoshell array.
Sci Rep
PUBLISHED: 08-26-2014
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Half-cone nanoshell arrays, fabricated by a simple and efficient colloidal lithography method, enable uni-directional liquid spreading on their hydrophilic asymmetric nanostructured surface. The preferred direction of the liquid flow is reversed when the surface is made hydrophobic. Accordingly, poly(N-isopropyl-acrylamide) is polymerized onto the surface for in-site controlling the transition of liquid spreading direction via its temperature dependent hydrophobicity. Furthermore, we also explain theoretically, that the spreading direction on hexagonal nanocone arrays is independent of the lattice orientation and only depends on the slanting direction. The insights gained from this work offer new opportunities for smart microfluidics, water harvesting and making use of other wetting conditions on demand.
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DNA methylation-mediated silencing of matricellular protein dermatopontin promotes hepatocellular carcinoma metastasis by ?3?1 integrin-Rho GTPase signaling.
Oncotarget
PUBLISHED: 08-24-2014
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Dermatopontin (DPT), a tyrosine-rich, acidic matricellular protein, has been implicated in several human cancers. However, its biological functions and molecular mechanisms in cancer progression, particular hepatocellular carcinoma (HCC), remain unknown. We demonstrated that DPT was significantly down-regulated in 202 HCC clinical samples and that its expression level was closely correlated with cancer metastasis and patient prognosis. The overexpression of DPT dramatically suppressed HCC cell migration in vitro and intrahepatic metastasis in vivo. We further revealed that the down-regulation of DPT in HCC was due to epigenetic silencing by promoter DNA methylation. And the inhibitory effects of DPT on HCC cell motility were associated with dysregulated focal adhesion assembly, decreased RhoA activity and reduced focal adhesion kinase (FAK) and c-Src tyrosine kinase (Src) phosphorylation, and all of these alterations required the involvement of integrin signaling. Furthermore, we determined that the inhibitory effects of DPT on HCC cell motility were primarily mediated through ?3?1 integrin. Our study provides new evidence for epigenetic control of tumor microenvironment, and suggests matricellular protein DPT may serve as a novel prognostic marker and act as a HCC metastasis suppressor.
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Epstein-Barr virus latent membrane protein 2A suppresses the expression of HER2 via a pathway involving TWIST and YB-1 in Epstein-Barr virus-associated gastric carcinomas.
Oncotarget
PUBLISHED: 08-20-2014
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To explore HER2 expression in Epstein-Barr virus-associated gastric carcinoma (EBVaGC) and the possible mechanisms causing down-regulation of HER2 expression in EBVaGC, we first evaluated HER2 and LMP2A expression on a clinicopathological-features matched cohort including 78 EBVaGC and 216 EBV-negative gastric carcinoma (EBVnGC) cases by immunohistochemistry. Cases with high HER2 expression in EBVaGC were significantly less than in EBVnGC (5.1% versus 23.7%; p<0.001), and none of the 34 LMP2A+ EBVaGC showed high HER2 expression. Further, overexpressing LMP2A in EBV-negative SGC7901 cells significantly decreased HER2, TWIST and YB-1 mRNA by 36.1%±8.1%, 87.6%±14.0% and 83.8%±5.7%, and protein by 44%, 57% and 49%, respectively. Additionally, the nucleus/cytoplasm ratios of TWIST and YB-1 were also decreased by 85% and 80%, respectively. Silencing LMP2A by siRNA in EBV-positive SNU719 cells for 48 h significantly increased HER2, TWIST and YB-1 mRNA to 276.7%±14.6%, 1284.8%±38.2% and 332.0%±15.5% and protein to 212%, 457% and 232%, respectively. The nucleus/cytoplasm ratios of TWIST and YB-1 were up-regulated by 4.00- and 3.57-fold, respectively, following LMP2A down-regulation. Moreover, LMP2A+/HER2low EBVaGC cases presented the best overall survival compared with LMP2A-/HER2low and LMP2A-/HER2high cases (p=0.003, log-rank test). These results suggest that LMP2A may suppress the HER2 expression through the TWIST/YB-1 axis in EBVaGC.
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Superovulation does not affect the endocrine activity nor increase susceptibility to carcinogenesis of uterine and mammary glands of female offspring in mice.
J. Assist. Reprod. Genet.
PUBLISHED: 08-10-2014
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To evaluate the dual effects of superovulation on the endocrine activity and susceptibility to carcinogenesis of uterine and mammary glands of female offspring in mice
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Distribution of metals and brominated flame retardants (BFRs) in sediments, soils and plants from an informal e-waste dismantling site, South China.
Environ Sci Pollut Res Int
PUBLISHED: 08-10-2014
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Brominated flame retardants (BFRs, including polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol-A (TBBPA)) and metals (Cu, Zn, Pb, Cd, Ni, Hg and As) in sediments, soils and herb plants from unregulated e-waste disposal sites were examined. The metal concentrations, ?PBDE and TBBPA concentrations in all samples from the examined e-waste dismantling sites were relatively high in comparison with those of rural and urban areas around the world. The PBDE and TBBPA levels in soils significantly decreased with increasing distance from the e-waste dismantling sites, indicating that PBDEs and TBBPA had similar transport potential from the e-waste dismantling process as a point source to the surrounding region. BDE-209 and TBBPA predominated in all samples, which is consistent with the evidence that the deca-BDE and TBBPA commercial mixtures were extensively used in electronic products. Metals, PBDEs and TBBPA displayed significant positive correlations with TOC, whereas the correlations with pH were insignificant, indicating that TOC was a major factor governing the spatial distribution, transportation and fate in sediments and soils. A significant relationship between log-transformed metals and BFR concentrations indicated common pollution sources. Moreover, cluster analysis and principal component analysis further confirmed that the metals and BFRs had a common source, and penta- and deca-BDE commercial products may be two sources of PBDEs in this region.
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Ballistic heat conduction and mass disorder in one dimension.
J Phys Condens Matter
PUBLISHED: 07-31-2014
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It is well-known that in the disordered harmonic chain, heat conduction is subballistic and the thermal conductivity (?) scales asymptotically as lim(L--> ?) ? ? L(0.5) where L is the chain length. However, using the nonequilibrium Green's function (NEGF) method and analytical modelling, we show that there exists a critical crossover length scale (LC) below which ballistic heat conduction (? ? L) can coexist with mass disorder. This ballistic-to-subballistic heat conduction crossover is connected to the exponential attenuation of the phonon transmittance function ? i.e. ?(?, L) = exp[-L/?(?)], where ? is the frequency-dependent attenuation length. The crossover length can be determined from the minimum attenuation length, which depends on the maximum transmitted frequency. We numerically determine the dependence of the transmittance on frequency and mass composition as well as derive a closed form estimate, which agrees closely with the numerical results. For the length-dependent thermal conductance, we also derive a closed form expression which agrees closely with numerical results and reproduces the ballistic to subballistic thermal conduction crossover. This allows us to characterize the crossover in terms of changes in the length, mass composition and temperature dependence, and also to determine the conditions under which heat conduction enters the ballistic regime. We describe how the mass composition can be modified to increase ballistic heat conduction.
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Facile synthesis of block copolymers by tandem ROMP and eROP from esters precursors.
Biomacromolecules
PUBLISHED: 07-22-2014
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In the present study, block copolymers were first synthesized through a tandem ring-opening metathesis polymerization (ROMP) and conventional enzymatic ring-opening polymerization (eROP) from hydroxyl initiator. Furthermore, a novel synthesis route, single-step eROP from ester precursor was successfully developed to synthesize targeted copolymers. The as-prepared polymers were analyzed by NMR, GPC, DSC, and MALDI-TOF-MS. There was no difference in the characteristic peaks of NMR between the end products obtained from these two synthetic routes. The GPC data showed that the copolymer obtained from single-step eROP was similar to the end product obtained from the traditional multistep synthesis method. Afterward, we used model compounds to carry out the conventional eROP and the single-step eROP. Finally, through the kinetic analysis and structural analysis of the resulting product, a reasonable initiation mechanism for this single-step eROP was elucidated.
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Functional characterization and phylogenetic analysis of acquired and intrinsic macrolide phosphotransferases in the Bacillus cereus group.
Environ. Microbiol.
PUBLISHED: 07-21-2014
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The Bacillus cereus group is composed of Gram-positive spore-forming bacteria of clinical and ecological importance. More than 200 B. cereus group isolates have been sequenced. However, there are few reports of B. cereus group antibiotic resistance genes. This study identified two functional classes of macrolide phosphotransferases (Mphs) in the B. cereus group. Cluster A Mphs inactivate 14- and 15-membered macrolides while Cluster B Mphs inactivate 14-, 15-, and 16-membered compounds. The genomic region surrounding the Cluster B Mph gene is related to various plasmid sequences, suggesting that this gene is an acquired resistance gene. In contrast, the Cluster A Mph gene is located in a chromosomal region conserved among all B. cereus group isolates, and data indicated that it was acquired early in the evolution of the group. Therefore, the Cluster A gene can be considered an intrinsic resistance gene. However, the gene itself is not present in all strains and our comparative genomics analyses showed that it is exchanged among strains of the B. cereus group by the mean of homologous recombination. These results provide an alternative mechanism to intrinsic resistance.
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Layer-dependent Band Alignment and Work Function of Few-Layer Phosphorene.
Sci Rep
PUBLISHED: 07-02-2014
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Using first-principles calculations, we study the electronic properties of few-layer phosphorene focusing on layer-dependent behavior of band gap, work function band alignment and carrier effective mass. It is found that few-layer phosphorene shows a robust direct band gap character, and its band gap decreases with the number of layers following a power law. The work function decreases rapidly from monolayer (5.16?eV) to trilayer (4.56?eV), and then slowly upon further increasing the layer number. Compared to monolayer phosphorene, there is a drastic decrease of hole effective mass along the ridge (zigzag) direction for bilayer phosphorene, indicating a strong interlayer coupling and screening effect. Our study suggests that 1). Few-layer phosphorene with a layer-dependent band gap and a robust direct band gap character is promising for efficient solar energy harvest. 2). Few-layer phosphorene outperforms monolayer counterpart in terms of a lighter carrier effective mass, a higher carrier density and a weaker scattering due to enhanced screening. 3). The layer-dependent band edges and work functions of few-layer phosphorene allow for modification of Schottky barrier with enhanced carrier injection efficiency. It is expected that few-layer phosphorene will present abundant opportunities for a plethora of new electronic applications.
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Asymmetric half-cone/nanohole array films with structural and directional reshaping of extraordinary optical transmission.
Nanoscale
PUBLISHED: 06-28-2014
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Structured films with periodic arrays of nanoholes covered by half-cone shells are fabricated via a simple and efficient colloidal lithography method. The designed films show strong polarization dependence in optical transmission. By decreasing the height of half-cone shells the peak shifts and this shift varies strongly for different orthogonal polarizations. Furthermore, the three-dimensional (3D) asymmetric arrays exhibit a pronounced increase in the transmission intensity by changing the direction of the incident light from the half-cone shell (shelter) side to the empty side. Special surface plasmon resonances excited by the unique 3D asymmetric structure are responsible for these novel properties, and the experimental results are in good agreement with numerical simulations. The nanostructured films in this work will be useful for metallic nanophotonic elements in many applications, including surface plasmon enhanced optical sensing and ultrafast optical switching, as well as versatile substrates for surface enhanced Raman spectroscopy, anisotropic wettability and other potential uses.
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[Molecular characterization of a HMG-CoA reductase gene from a rare and endangered medicinal plant, Dendrobium officinale].
Yao Xue Xue Bao
PUBLISHED: 06-26-2014
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The 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) catalyzes the conversion of HMG-CoA to mevalonate in mavalonic acid pathway, which is the first committed step for isoprenoid biosynthesis in plants. However, it still remains unclear whether HGMR gene plays a role in the isoprenoid biosynthesis in Dendrobium officinale, an endangered epiphytic orchid species. In the present study, a HMGR encoding gene, designed as DoHMGR1 (GenBank accession JX272632), was identified from D. officinale using the reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods, for the first time. The full length cDNA of DoHMGR1 was 2 071 bp in length and encoded a 562-aa protein with a molecular weight of 59.73 kD and an isoelectric point (pI) of 6.18. The deduced DoHMGR1 protein, like other HMGR proteins, constituted four conserved domains (63-561, 147-551, 268-383 and 124-541) and two transmembrane motifs (42-64 and 85-107). Multiple sequence alignment and phylogenetic analyses demonstrated that DoHMGR1 had high identity (67%-89%) to a number of HMGR genes from various plants and was closely related to Vanda hybrid cultivar, rice and maize monocots. Real time quantitative PCR (qPCR) analysis revealed that DoHMGR1 was expressed in the three included organs. The transcripts were the most abundant in the roots with 2.13 fold over that in the leaves, followed by that in the stems with 1.98 fold. Molecular characterization of DoHMGR1 will be useful for further functional elucidation of the gene involving in isoprenoid biosynthesis pathway in D. officinale.
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Coexisting glomerular IgA deposition and IgG-kappa multiple myeloma.
Ren Fail
PUBLISHED: 06-24-2014
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Multiple myeloma (MM) is a common malignancy that often results in many kinds of kidney injuries for the abnormal monoclonal immunoglobulin. Here, we present an IgG-kappa type MM case accompanied by renal IgA deposition combined with IgG-kappa. The patient was treated with prednisone plus mycophenolate mofetil, and got a satisfactory remission. Although it cannot be determined whether the IgA deposition was secondary to MM, this was the first report of coexisting mesangial proliferative nephritis with IgA deposition and IgG-kappa type MM.
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Characterization of heavy metals and brominated flame retardants in the indoor and outdoor dust of e-waste workshops: implication for on-site human exposure.
Environ Sci Pollut Res Int
PUBLISHED: 06-17-2014
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Forty-four indoor and outdoor dust samples were collected from e-waste workshops and were analyzed to characterize the heavy metals and brominated flame retardants (BFRs) as well as on-site human exposure. The results showed that the most abundant Polybrominated diphenyl ethers (PBDE) congener from three sites was deca-BDE, and it was penta-BDE for the other site. A significant and positive association was found between BDE-209 and decabromodiphenyl ethane (DBDPE). The high percentage of nona-BDE indicated the debromination of deca-BDE during e-waste recycling. The ratio comparison of BDE-47 to (BDE-100?+?BDE-99) indicated that the outdoor dust went through more physiochemical processes. The enrichment factors for Cu and Pb were high in both the indoor and outdoor samples. Cd significantly exceeded the Chinese soil guideline grade III. The PCA results combined with the enrichment factor (EF) values suggested common sources and behaviours of Cu, Pb and Sb in the indoor dust. Co, Cr, Ni, Zn and Mn in the outdoor samples were more likely affected by crust. Strong correlations were found only for Pb and Sb with polybrominated diphenyl ethers (PBDEs). The hazard index for on-site human exposure to Pb was at a chronic risk. Despite the low deleterious risk of BFRs, concern should be given to DBDPE; the chronic toxicity of which is not known.
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Draft genome sequence of Bacillus amyloliquefaciens HB-26.
Stand Genomic Sci
PUBLISHED: 06-15-2014
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Bacillus amyloliquefaciens HB-26, a Gram-positive bacterium was isolated from soil in China. SDS-PAGE analysis showed this strain secreted six major protein bands of 65, 60, 55, 34, 25 and 20 kDa. A bioassay of this strain reveals that it shows specific activity against P. brassicae and nematode. Here we describe the features of this organism, together with the draft genome sequence and annotation. The 3,989,358 bp long genome (39 contigs) contains 4,001 protein-coding genes and 80 RNA genes.
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PNMA1 promotes cell growth in human pancreatic ductal adenocarcinoma.
Int J Clin Exp Pathol
PUBLISHED: 06-15-2014
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Paraneoplastic Ma1 (PNMA1) is a member of an expanding family of 'brain/testis' proteins involved in an autoimmune disorder defined as paraneoplastic neurological syndrome (PNS). Although it is widely studied in PNS, little is known about the underlying clinical significance and biological function of PNMA1 in tumors. Here, we find that elevated PNMA1 expression is more commonly observed in pancreatic ductal adenocarcinoma (PDAC) cell lines, compared with normal pancreatic cell and tissues from pancreatic ductal adenocarcinoma patient. Besides, higher PNMA1 expression is closely correlated with large tumor size. Suppression of endogenous PNMA1 expression decreases cell viability and promotes cell apoptosis. Subsequent studies reveal that the PI3K/AKT, MAPK/ERK pathway and members of the anti-apoptotic Bcl-2 family may be involved in the pro-survival and anti-apoptotic effect of PNMA1 on PDAC. Taken together, this study provides evidence that PNMA1 is involved in tumor growth of pancreatic carcinoma and PNMA1-related pathways might represent a new treatment strategy.
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Endosomal trafficking of nanoformulated antiretroviral therapy facilitates drug particle carriage and HIV clearance.
J. Virol.
PUBLISHED: 06-11-2014
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Limitations of antiretroviral therapy (ART) include poor patient adherence, drug toxicities, viral resistance, and failure to penetrate viral reservoirs. Recent developments in nanoformulated ART (nanoART) could overcome such limitations. To this end, we now report a novel effect of nanoART that facilitates drug depots within intracellular compartments at or adjacent to the sites of the viral replication cycle. Poloxamer 407-coated nanocrystals containing the protease inhibitor atazanavir (ATV) were prepared by high-pressure homogenization. These drug particles readily accumulated in human monocyte-derived macrophages (MDM). NanoATV concentrations were ?1,000 times higher in cells than those that could be achieved by the native drug. ATV particles in late and recycling endosome compartments were seen following pulldown by immunoaffinity chromatography with Rab-specific antibodies conjugated to magnetic beads. Confocal microscopy provided cross validation by immunofluorescent staining of the compartments. Mathematical modeling validated drug-endosomal interactions. Measures of reverse transcriptase activity and HIV-1 p24 levels in culture media and cells showed that such endosomal drug concentrations enhanced antiviral responses up to 1,000-fold. We conclude that late and recycling endosomes can serve as depots for nanoATV. The colocalization of nanoATV at endosomal sites of viral assembly and its slow release sped antiretroviral activities. Long-acting nanoART can serve as a drug carrier in both cells and subcellular compartments and, as such, can facilitate viral clearance.
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Towards intrinsic charge transport in monolayer molybdenum disulfide by defect and interface engineering.
Nat Commun
PUBLISHED: 06-02-2014
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Molybdenum disulfide is considered as one of the most promising two-dimensional semiconductors for electronic and optoelectronic device applications. So far, the charge transport in monolayer molybdenum disulfide is dominated by extrinsic factors such as charged impurities, structural defects and traps, leading to much lower mobility than the intrinsic limit. Here we develop a facile low-temperature thiol chemistry route to repair the sulfur vacancies and improve the interface, resulting in significant reduction of the charged impurities and traps. High mobility >80?cm(2)?V(-1)?s(-1) is achieved in backgated monolayer molybdenum disulfide field-effect transistors at room temperature. Furthermore, we develop a theoretical model to quantitatively extract the key microscopic quantities that control the transistor performances, including the density of charged impurities, short-range defects and traps. Our combined experimental and theoretical study provides a clear path towards intrinsic charge transport in two-dimensional dichalcogenides for future high-performance device applications.
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Using portable X-ray fluorescence spectrometry and GIS to assess environmental risk and identify sources of trace metals in soils of peri-urban areas in the Yangtze Delta region, China.
Environ Sci Process Impacts
PUBLISHED: 05-31-2014
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Portable X-ray fluorescence (PXRF) spectrometry may be very suitable for a fast and effective environmental assessment and source identification of trace metals in soils. In this study, topsoils (0-10 cm) at 139 sites were in situ scanned for total trace metals (Cr, Cu, Ni, Pb and Zn) and arsenic concentrations by PXRF in a typical town in Yangtze Delta region of Jiangsu province, China. To validate the utility of PXRF, 53 samples were collected from the scanning sites for the determination of selected trace metals using conventional methods. Based on trace metal concentrations detected by in situ PXRF, the contamination extent and sources of trace metals were studied via geo-accumulation index, multivariate analysis and geostatistics. The trace metal concentrations determined by PXRF were similar to those obtained via conventional chemical analysis. The median concentration of As, Cr, Cu, Ni, Pb and Zn in soils were 10.8, 56.4, 41.5, 43.5, 33.5, and 77.7 mg kg(-1), respectively. The distribution patterns of Cr, Cu, Ni, Pb, and Zn were mostly affected by anthropogenic sources, while As was mainly derived from lithogenic sources. Overall, PXRF has been successfully applied to contamination assessment and source identification of trace metals in soils.
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Inhibition of Rho-kinase differentially affects axon regeneration of peripheral motor and sensory nerves.
Exp. Neurol.
PUBLISHED: 05-30-2014
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The small GTPase RhoA and its down-stream effector Rho-kinase (ROCK) are important effector molecules of the neuronal cytoskeleton. Modulation of the RhoA/ROCK pathway has been shown to promote axonal regeneration, however in vitro and animal studies are inconsistent regarding the extent of axonal outgrowth induced by pharmacological inhibition of ROCK. We hypothesized that injury to sensory and motor nerves result in diverse activation levels of RhoA, which may impact the response of those nerve fiber modalities to ROCK inhibition. We therefore examined the effects of Y-27632, a chemical ROCK inhibitor, on the axonal outgrowth of peripheral sensory and motor neurons grown in the presence of growth-inhibiting chondroitin sulfate proteoglycans (CSPGs). In addition we examined the effects of three different doses of Y-27632 on nerve regeneration of motor and sensory nerves in animal models of peripheral nerve crush. In vitro, sensory neurons were less responsive to Y-27632 compared to motor neurons in a non-growth permissive environment. These differences were associated with altered expression and activation of RhoA in sensory and motor axons. In vivo, systemic treatment with high doses of Y-27632 significantly enhanced the regeneration of motor axons over short distances, while the regeneration of sensory fibers remained largely unchanged. Our results support the concept that in a growth non-permissive environment, the regenerative capacity of sensory and motor axons is differentially affected by the RhoA/ROCK pathway, with motor neurons being more responsive compared to sensory. Future treatments, that are aimed to modulate RhoA activity, should consider this functional diversity.
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Elevated autocrine EDIL3 protects hepatocellular carcinoma from anoikis through RGD-mediated integrin activation.
Mol. Cancer
PUBLISHED: 05-10-2014
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A remolded microenvironment in hepatocellular carcinoma (HCC) caused by abnormally expressed matricellular proteins could promote HCC progression. The cell-matrix interactions mediated by integrins play an important role in tumor microenvironment. Epidermal Growth Factor-like repeats and Discoidin I-Like Domains 3 (EDIL3), an extracellular matrix (ECM) protein with angiogenic and anti-inflammatory effects, is abnormally highly expressed in HCC. Here we aim to analyze its expression in liver and HCC tissues, investigate the underlined mechanisms accounted for HCC progression.
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Lysyl oxidase-like 4 (LOXL4) promotes proliferation and metastasis of gastric cancer via FAK/Src pathway.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 04-14-2014
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Lysyl oxidase-like 4 (LOXL4) has been found up-regulated in a variety of human malignancies, but its clinical significance and functional roles in gastric cancer (GC) remain unknown.
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Th2 lymphocytes migrating to the bone marrow under high-altitude hypoxia promote erythropoiesis via activin A and interleukin-9.
Exp. Hematol.
PUBLISHED: 04-08-2014
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The mechanism of accelerated erythropoiesis under the hypoxic conditions of high altitude (HA) remains largely obscure. Here, we investigated the potential role of bone marrow (BM) T cells in the increased production of erythrocytes at HA. We found that mice exposed to a simulated altitude of 6,000 m for 1-3 weeks exhibited a significant expansion of BM CD4+ cells, mainly caused by increasing T helper 2 (Th2) cells. Using a coculture model of BM T cells and hematopoietic stem/progenitor cells, we observed that BM CD4+ cells from hypoxic mice induced erythroid output more easily, in agreement with the erythroid-enhancing effect observed for Th2-condition-cultured BM CD4+ cells. It was further demonstrated that elevated secretion of activin A and interleukin-9 by BM Th2 cells of hypoxic mice promoted erythroid differentiation of hematopoietic stem/progenitor cells and the growth of erythroblasts, respectively. Our study also provided evidence that the CXCL12-CXCR4 interaction played an important role in Th2 cell trafficking to the BM under HA conditions. These results collectively suggest that Th2 cells migrating to the BM during HA exposure have a regulatory role in erythropoiesis, which provides new insight into the mechanism of high altitude polycythemia.
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Evaluation of high-risk clinicopathological indicators in gastrointestinal stromal tumors for prognosis and imatinib treatment outcome.
BMC Gastroenterol
PUBLISHED: 02-23-2014
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Although the clinical benefit of imatinib adjuvant therapy for high-risk patients with gastrointestinal stromal tumor (GIST) has been proven, the recurrence rate still remains high. This study aimed to sub-divide high-risk GIST patients with some "very high-risk" factors for more precise prognostic indicator, and possible association with efficiency of imatinib adjuvant therapy.
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Retinoic acid receptor-related receptor alpha (RORalpha) is a prognostic marker for hepatocellular carcinoma.
Tumour Biol.
PUBLISHED: 02-22-2014
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Retinoic acid receptor-related receptor alpha (RORalpha) has been proven to play a tumor suppressive role in certain types of solid tumors. However, the clinical characteristic of RORalpha has not been reported by far. This study investigated the expression of RORalpha in hepatocellular carcinoma (HCC) and evaluated its relationship with clinical parameters and prognosis in HCC patients. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blot analyses were performed to detect RORalpha expression levels in 20 paired HCC and corresponding adjacent non-cancerous tissues. Immunohistochemistry was performed on 100 archived paraffin-embedded HCC samples. Statistical analyses evaluated the correlations between RORalpha expression and clinicopathological features. qRT-PCR showed that RORalpha mRNA expression was significantly down-regulated in tumors compared to the adjacent non-cancerous tissues, and Western blots found that RORalpha protein expression was also reduced in tumor tissues. Immunohistochemical assays revealed that decreased RORalpha expression was present in 65 % of HCC patients. Correlation analyses showed that RORalpha expression was significantly correlated with serum alpha fetoprotein (AFP, p?=?0.005), pathology grade (p?
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Endogenous salicylic acid accumulation is required for chilling tolerance in cucumber (Cucumis sativus L.) seedlings.
Planta
PUBLISHED: 02-17-2014
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Salicylic acid (SA) is an important plant hormone, and its exogenous application can induce tolerance to multiple environmental stresses in plants. In this study, we examine the potential involvement of endogenous SA in response to chilling in cucumber (Cucumis sativus L.) seedlings. A low temperature of 8 °C induces a moderate increase in endogenous SA levels. Chilling stimulates the enzymatic activities and the expression of genes for phenylalanine ammonia-lyase (PAL) and benzoic acid-2-hydroxylase rather than isochorismate synthase. This indicates that the PAL enzymatic pathway contributes to chilling-induced SA production. Cucumber seedlings pretreated with SA biosynthesis inhibitors accumulate less endogenous SA and suffer more from chilling damage. The expression of cold-responsive genes is also repressed by SA inhibitors. The reduction in stress tolerance and in gene expression can be restored by the exogenous application of SA, confirming the critical roles of SA in chilling responses in cucumber seedlings. Furthermore, the inhibition of SA biosynthesis under chilling stress results in a prolonged and enhanced hydrogen peroxide (H2O2) accumulation. The application of exogenous SA and the chemical scavenger of H2O2 reduces the excess H2O2 and alleviates chilling injury. In contrast, the protective effects of SA are negated by foliar spraying with high concentrations of H2O2 and an inhibitor of the antioxidant enzyme. These results suggest that endogenous SA is required in response to chilling stress in cucumber seedlings, by modulating the expression of cold-responsive genes and the precise induction of cellular H2O2 levels.
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Monoamine oxidase A suppresses hepatocellular carcinoma metastasis by inhibiting the adrenergic system and its transactivation of EGFR signaling.
J. Hepatol.
PUBLISHED: 02-17-2014
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Monoamine oxidase A (MAOA), a catecholamine neurotransmitter degrading enzyme, is closely associated with neurological and psychiatric disorders. However, its role in cancer progression remains unknown.
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LRG1 is an independent prognostic factor for endometrial carcinoma.
Tumour Biol.
PUBLISHED: 02-13-2014
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Endometrial cancer (EC) is one of the most common female malignancies. The patients with high-risk factors may have poor prognosis. Therefore, there is an urgent need to find a new molecule to more accurately predict survival of patients. Leucine-rich-alpha-2-glycoprotein1 (LRG1), one of leucine-rich repeat family, was closely associated with cancer metastasis and poor prognosis. The biological functions and the expression level of LRG1 remain obscure in EC. In this study, by immunohistochemical analysis of 242 EC patient tissues, we found that LRG1 expression was associated with stage and lymphatic metastasis in both test cohort (133 patients) and validation cohort (109 patients). Furthermore, to investigate the prognostic value of LRG1 in endometrial carcinoma, we analyzed the correlation between variables and overall survival with Cox proportional hazard regression. The result showed that LRG1 was an independent prognostic factor for overall survival of endometrial carcinoma patients. To further evaluate the prognostic efficiency of LRG1 in endometrial carcinoma, we compared the sensitivity and specificity of LRG1 in endometrial carcinoma prognosis by logistic regression. The result showed that LRG1 combining with other clinicopathological risk factors was a stronger prognostic model than clinicopathological risk factors alone or their combination. Thus, LRG1 potentially offered clinical value in directing personal treatment for endometrial carcinoma patients.
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Comparison of the Inhibitory Potential of Bavachalcone and Corylin against UDP-Glucuronosyltransferases.
Evid Based Complement Alternat Med
PUBLISHED: 02-10-2014
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Bavachalcone and corylin are two major bioactive compounds isolated from Psoralea corylifolia L., which has been widely used as traditional Chinese medicine for many years. As two antibiotic or anticancer drugs, bavachalcone and corylin are used in combination with other drugs; thus it is necessary to evaluate potential pharmacokinetic herb-drug interactions (HDI) of the two bioactive compounds. The aim of the present study was to compare the effects of liver UDP-glucuronosyltransferase (UGT) 1A1, UGT1A3, UGT1A7, UGT1A8, UGT 1A10, and UGT2B4 inhibited by bavachalcone and corylin. 4-Methylumbelliferone (4-MU) was used as a nonspecific "probe" substrate. Bavachalcone had stronger inhibition on UGT1A1 and UGT1A7 than corylin which did not inhibit UGT1A1, UGT1A3, UGT1A7, UGT1A8, UGT1A10, and UGT2B4. Data fitting using Dixon and Lineweaver-Burk plots demonstrated the noncompetitive inhibition of bavachalcone against UGT1A1 and UGT1A7-mediated 4-MU glucuronidation reaction. The values of inhibition kinetic parameters (Ki) were 5.41? ? M and 4.51? ? M for UGT1A1 and UGT1A7, respectively. The results of present study suggested that there was a possibility of UGT1A1 and UGT1A7 inhibition-based herb-drug interaction associated with bavachalcone and provided the basis for further in vivo studies to investigate the HDI potential between bavachalcone and UGT substrates.
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CTHRC1 acts as a prognostic factor and promotes invasiveness of gastrointestinal stromal tumors by activating Wnt/PCP-Rho signaling.
Neoplasia
PUBLISHED: 02-10-2014
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Gastrointestinal stromal tumors (GISTs) are the major gastrointestinal mesenchymal tumors with a variable malignancy ranging from a curable disorder to highly malignant sarcomas. Metastasis and recurrence are the main causes of death in GIST patients. To further explore the mechanism of metastasis and to more accurately estimate the recurrence risk of GISTs after surgery, the clinical significance and functional role of collagen triple helix repeat containing-1 (CTHRC1) in GIST were investigated. We found that CTHRC1 expression was gradually elevated as the risk grade of NIH classification increased, and was closely correlated with disease-free survival and overall survival in 412 GIST patients. In vitro experiments showed that recombinant CTHRC1 protein promoted the migration and invasion capacities of primary GIST cells. A luciferase reporter assay and pull down assay demonstrated that recombinant CTHRC1 protein activated noncanonical Wnt/PCP-Rho signaling but inhibited canonical Wnt signaling. The pro-motility effect of CTHRC1 on GIST cells was reversed by using a Wnt5a neutralizing antibody and inhibitors of Rac1 or ROCK. Taken together, these data indicate that CTHRC1 may serve as a new predictor of recurrence risk and prognosis in post-operative GIST patients and may play an important role in facilitating GIST progression. Furthermore, CTHRC1 promotes GIST cell migration and invasion by activating Wnt/PCP-Rho signaling, suggesting that the CTHRC1-Wnt/PCP-Rho axis may be a new therapeutic target for interventions against GIST invasion and metastasis.
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Effects of varying tissue sizes on the efficiency of baboon ovarian tissue vitrification.
Cryobiology
PUBLISHED: 02-05-2014
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The aim of this study was to detect the effects of varying tissue sizes on the efficiency of baboon ovarian tissue vitrification.
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Microfilament regulatory protein MENA increases activity of RhoA and promotes metastasis of hepatocellular carcinoma.
Exp. Cell Res.
PUBLISHED: 02-01-2014
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Mammalian enabled (MENA), usually known as a direct regulator of microfilament polymerization and bundling, promotes metastasis in various cancers. Here we focus on the role of MENA in hepatocellular carcinoma (HCC) metastasis and the relevant mechanism from the view of RhoA activity regulation. By HCC tissue microarray analysis, we found that MENA expression was positively associated with satellite lesions (P<0.01) and vascular invasion (P<0.01). Cases with membrane reinforcement of MENA staining in HCC tissues had significantly higher rates of early recurrence in the intermediate MENA expression group. Knockdown of MENA significantly suppressed HCC cell migration and invasion in vitro, as well as their intrahepatic and distant metastasis in vivo. Knockdown of MENA also decreased filopodia and stress fibers in SMMC-7721 cells. Furthermore, a decrease of RhoA activity was detected by a pull-down assay in SMMC-7721-shMENA cells. The ROCK inhibitor, Y-27632, suppressed migration of both MENA knockdown SMMC-7721 cells and control cells, but diminished their difference. Thus, our findings suggest that MENA promotes HCC cell motility by activating RhoA.
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A bond-order theory on the phonon scattering by vacancies in two-dimensional materials.
Sci Rep
PUBLISHED: 01-30-2014
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We theoretically investigate the phonon scattering by vacancies, including the impacts of missing mass and linkages (?(V)(-1)) and the variation of the force constant of bonds associated with vacancies (?(A)(-1)) by the bond-order-length-strength correlation mechanism. We find that in bulk crystals, the phonon scattering rate due to change of force constant ?(A)(-1) is about three orders of magnitude lower than that due to missing mass and linkages ?(V)(-1). In contrast to the negligible ?(A)(-1) in bulk materials, ?(A)(-1) in two-dimensional materials can be 3-10 folds larger than ?(V)(-1). Incorporating this phonon scattering mechanism to the Boltzmann transport equation derives that the thermal conductivity of vacancy defective graphene is severely reduced even for very low vacancy density. High-frequency phonon contribution to thermal conductivity reduces substantially. Our findings are helpful not only to understand the severe suppression of thermal conductivity by vacancies, but also to manipulate thermal conductivity in two-dimensional materials by phononic engineering.
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Increased severity of inflammation correlates with elevated expression of TRPV1 nerve fibers and nerve growth factor on interstitial cystitis/bladder pain syndrome.
Urol. Int.
PUBLISHED: 01-23-2014
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Although evidence supports a role for inflammation in interstitial cystitis/bladder pain syndrome (IC/BPS), the mechanism remains unknown. We determined whether inflammation causes an elevated expression of nerve growth factor (NGF) and transient receptor potential vanilloid receptor subtype 1 (TRPV1) and correlated them with the symptoms.
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Overexpression of hypoxia-inducible factor-1? and vascular endothelial growth factor in sacral giant cell tumors and the correlation with tumor microvessel density.
Exp Ther Med
PUBLISHED: 01-22-2014
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Although classified as benign, giant cell tumors of the bone (GCTB) may be aggressive, recur and even metastasize to the lungs. In addition, the pathogenesis and histogenesis remain unclear; thus, the driving factors behind the strong tumor growth capacity of GCTB require investigation. In the present study, the expression levels of hypoxia-inducible factor (HIF)-1? and vascular endothelial growth factor (VEGF), which are promoted by hypoxic conditions, were determined in 22 sacral GCTB samples using immunohistochemistry and western blot analysis. Furthermore, CD34 expression was analyzed using these methods. The correlation between HIF-1? or VEGF expression and the tumor microvessel density (MVD) was then determined. The results demonstrated that HIF-1?, VEGF and CD34 were overexpressed in the 22 sacral GCTB specimens, and overexpression of HIF-1? and VEGF correlated with the tumor MVD. Thus, the present study has provided novel indicators for the tumor growth capacity of GCTBs.
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Augmenting multi-instance multilabel learning with sparse bayesian models for skin biopsy image analysis.
Biomed Res Int
PUBLISHED: 01-18-2014
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Skin biopsy images can reveal causes and severity of many skin diseases, which is a significant complement for skin surface inspection. Automatic annotation of skin biopsy image is an important problem for increasing efficiency and reducing the subjectiveness in diagnosis. However it is challenging particularly when there exists indirect relationship between annotation terms and local regions of a biopsy image, as well as local structures with different textures. In this paper, a novel method based on a recent proposed machine learning model, named multi-instance multilabel (MIML), is proposed to model the potential knowledge and experience of doctors on skin biopsy image annotation. We first show that the problem of skin biopsy image annotation can naturally be expressed as a MIML problem and then propose an image representation method that can capture both region structure and texture features, and a sparse Bayesian MIML algorithm which can produce probabilities indicating the confidence of annotation. The proposed algorithm framework is evaluated on a real clinical dataset containing 12,700 skin biopsy images. The results show that it is effective and prominent.
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Sick sinus syndrome associated with hypopituitarism: a case report and literature review.
J Biomed Res
PUBLISHED: 01-16-2014
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Though an association between autoimmune diseases and sick sinus syndrome has been reported, there has been no report on the association of hypopituitarism and sick sinus syndrome. Herein, we provide the first case report of hypopituitarism accompanying sick sinus syndrome in a 51-year-old woman presented to our hospital with syncope due to cardiac arrest. The patient was successfully managed by pacemaker installation and hormone replacement therapy.
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Quantitative MRI for hepatic fat fraction and T2* measurement in pediatric patients with non-alcoholic fatty liver disease.
Pediatr Radiol
PUBLISHED: 01-14-2014
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Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children. The gold standard for diagnosis is liver biopsy. MRI is a non-invasive imaging method to provide quantitative measurement of hepatic fat content. The methodology is particularly appealing for the pediatric population because of its rapidity and radiation-free imaging techniques.
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In vitro maturation of oocytes is not a risk factor for adult metabolic syndrome of mouse offspring.
Eur. J. Obstet. Gynecol. Reprod. Biol.
PUBLISHED: 01-11-2014
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To evaluate the effect of in vitro maturation (IVM) of oocytes on the serum cholesterol profile, glucose and insulin tolerance, blood pressure, and heart rate of adult mouse offspring.
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Silencing of WISP3 suppresses gastric cancer cell proliferation and metastasis and inhibits Wnt/?-catenin signaling.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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CCN6/Wnt1-inducible signaling protein-3 (CCN6/WISP3) is a cysteine-rich protein that belongs to the CCN (Cyr61, CTGF, Nov) family of matricellular proteins, which are often dysregulated in cancers. However, the functional role and clinical significance of WISP3 in gastric cancer remain unclear. In this study, we found that silencing of WISP3 suppressed gastric cancer cell proliferation, migration and invasion. Cell adhesion to collagens (collagen I and IV), but not to fibronectin, were significantly inhibited by silencing of WISP3. Furthermore, silencing of WISP3 prevented ?-catenin transferring from cell cytoplasm to nuclear, and suppressed canonical Wnt/?-catenin signaling and its downstream target genes, cyclin D1 and TCF-4. By immunohistochemical analysis of 379 patients, we found that the expression of WISP3 is closely associated with gastric cancer size and tumor invasion, and indicates a poor prognosis in both test cohort (253 patients) and validation cohort (126 patients). Moreover, the expression of WISP3 was positively correlated with the expression of cyclin D1 and TCF-4 in gastric cancer tissues. Taken together, our data suggests that WISP3 might be a promising prognostic factor and WISP3-Wnt/?-catenin axis may be a new therapeutic target for the intervention of gastric cancer growth and metastasis.
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Cytohesin-3 is upregulated in hepatocellular carcinoma and contributes to tumor growth and vascular invasion.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Hepatocellular carcinoma (HCC) is a malignant tumor with high morbidity and mortality, and is characterized by high potential for metastasis and recurrence. The outcome of it is still poor due to lacking of targeted therapeutic strategies. There is an urgent need to find new therapeutic targets for interventions against HCC metastasis and recurrence. In the present study, we found cytohesin-3, a member of the cytohesin family, was upregulated in HCC tissues, and its expression was negatively correlated with the overall survival and relapse-free survival of HCC patients. Further clinicopathological correlation analysis revealed that cytohesin-3 expression was related with tumor size and vascular invasion. And in vitro studies revealed that knock-down of cytohesin-3 suppressed HCC cells proliferation and migration. These results suggest that cytohesin-3 may act as a novel prognostic factor of HCC, and it might also be useful to exploit targeted therapeutic drugs against HCC growth and metastasis.
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Rictor is an independent prognostic factor for endometrial carcinoma.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Early-stage endometrial carcinoma (EC) patients have a high cure rate; however, those with high-risk factors may have poor prognosis. Thus, there is an urgent need for searching for new prognostic molecules to more accurately predict survival of patients. We detected the Rictor mRNA expression level in 30 fresh EC tissue and 17 normal endometrial tissue samples with real-time quantitative RT-PCR and Rictor protein expression level in 134 (test cohort) and 115 (validation cohort) paraffin tissue samples by immunohistochemistry, analyzed the correlation between variables and overall survival (OS) using Cox proportional hazards regression, compared the prognostic accuracy of Rictor with other clinicopathological risk factors by logistic regression. The results showed that Rictor mRNA expression of EC is higher than that of normal endometrium; Rictor protein expression level was closely correlated with FIGO stage, grade and vascular invasion in both cohorts; a univariate analysis showed that the pathological type, stage, grade, vascular invasion, lymphatic metastasis and Rictor were predictors of OS in both cohorts; furthermore, multivariate Cox proportional hazards regression analysis indicated that vascular invasion and Rictor were independent prognostic factors for EC in both cohorts; an ROX curve comparison showed that the area under the curve (AUC) for Rictor combined with other clinicopathological prognostic factors was higher than any individual factor or other clinicopathological prognostic factors' combination. Based on the above data, we concluded that Rictor is an independent prognostic factor for EC. It combined with other clinicopathological risk factors was a stronger prognostic model than individual risk factor or their combination.
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Transcatheter pulmonary valve replacement by hybrid approach using a novel polymeric prosthetic heart valve: proof of concept in sheep.
PLoS ONE
PUBLISHED: 01-01-2014
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Since 2000, transcatheter pulmonary valve replacement has steadily advanced. However, the available prosthetic valves are restricted to bioprosthesis which have defects like poor durability. Polymeric heart valve is thought as a promising alternative to bioprosthesis. In this study, we introduced a novel polymeric transcatheter pulmonary valve and evaluated its feasibility and safety in sheep by a hybrid approach.
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SERPINA3 promotes endometrial cancer cells growth by regulating G2/M cell cycle checkpoint and apoptosis.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Endometrial carcinoma (EC) is the most common gynecologic cancer worldwide and is one of the leading causes of death in women. Therefore, it is urgent to elucidate the pathological mechanisms of EC. SERPINA3 is a member of the serpin super-family of protease inhibitors. Its aberrant expression has been observed in various tumor cells. However, its clinical significance and biological function in endometrial cancer remains unknown. In the present study, we demonstrated that SERPINA3 expression was significantly up-regulated in EC samples and was closely correlated with lower differentiation, higher stage, positive lymph node or vascular thrombosis and negative estrogen receptor (ER), indicating a poor prognosis. We then demonstrated that SERPINA3 promoted EC cells proliferation by regulating G2/M checkpoint in cell cycle and inhibited cells apoptosis, and we further uncovered that the pro-proliferative effect of SERPINA3 on EC was likely ascribed to the activation of MAPK/ERK1/2 and PI3K/AKT signaling. The results of our study may provide insight into the application of SERPINA3 as a novel predictor of clinical outcomes and a potential therapeutic target of EC.
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Dysregulated cell mechanical properties of endometrial stromal cells from endometriosis patients.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Endometriosis, diagnosed with ectopically implanted endometrial stromal cells (ESC) and epithelial cells to a location outside the uterine cavity, seriously threaten the quality of life and reproductive ability of women, yet the mechanisms and the pathophysiology of the disease remain unclear. Specially, the functional changes of ESC during endometriosis progression need in-depth investigation. In this study, we characterized mechanical properties of normal ESC (NESC) from healthy women and eutopic ESC (EuESC) and ectopic ESC (EcESC) from endometriosis patients. We found the collagen lattice contractile ability of EuESC was significantly stronger than that of NESC, and the cell mobility of EuESC and EcESC was significantly greater than that of NESC. Furthermore, the expression of F-actin and vinculin in NESC, EuESC and EcESC cells progressively increased, and the Rho GTPase activity, of which RhoA exhibited the highest activity, in the three cells gradually increased. Collectively, these results suggest that the mechanical characteristics of NESC, EuESC and EcESC cells exhibited progressive abnormalities. Therefore, the biomechanics of endometrial stromal cells may be a potent target for intervention in patients with endometriosis.
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OPN and ?v?3 expression are predictors of disease severity and worse prognosis in hepatocellular carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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Expressions of OPN and ?v?3 are associated with a poor prognosis in many malignancies. However, their relationship in hepatocellular carcinoma remains unclear. We systematically collected hepatocellular carcinoma tissue samples from 305 patients over 3 years, and analyzed the status of OPN and ?v?3 in hepatocellular carcinoma and correlate expression with patient disease status and survival outcome. Our study results indicated that OPN and ?v?3 are expressed at significantly higher rates in hepatocellular carcinoma compared with adjacent non-tumorous tissue (69.5% vs 18.4%, p<0.01 and 77.4% vs 21.6%, p<0.01, respectively). Both OPN and ?v?3 expression levels are associated with poor prognostic factors, including tumor size, capsular invasion, tumor thrombus of the portal vein, metastasis of the lymph node and clinical staging. Patients expressing OPN and ?v?3 had significantly shorter survival compared with patients negative for protein expression (p<0.01). Multivariate analysis also showed that both OPN and ?v?3 expression are independent prognostic factors for poorer survival in hepatocellular carcinoma. By this study, we conclude that OPN and ?v?3 are negative prognostic predictors in patients with hepatocellular carcinoma. The expressions of both OPN and ?v?3 are associated with worse survival outcome.
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The effects of short-term and long-term exposure to a high altitude hypoxic environment on neurobehavioral function.
High Alt. Med. Biol.
PUBLISHED: 12-31-2013
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Abstract Zhang, Gang, Si-Min Zhou, Chao Yuan, Huai-Jun Tian, Peng Li, and Yu-Qi Gao. The effects of short-term and long-term exposure to a high altitude hypoxic environment on neurobehavioral function. High Alt Med Biol 14:338-341, 2013.-Aims: Examined the change in neurobehavioral function of individuals acclimated to high altitudes and those native to high altitudes. Methods: A neurobehavioral core test battery approved by the WHO (WHO-NCTB) was used to evaluate the effects of high altitude hypoxia on neurobehavioral function. The WHO-NCTB is composed of seven individual tests: a mood state profile, simple reaction time test, digit span test, Santa Ana manual dexterity test, digit symbol test, Benton visual retention test, and pursuit aiming test. Results: The values from the Santa Ana manual dexterity test, digit symbol test, and pursuit aiming test from sea-level subjects acclimated for 5 days at 3700?m were significantly decreased when compared with the same subjects at sea level. The values from the digit span, Santa Ana manual dexterity, digit symbol, Benton visual retention and pursuit aiming tests in subjects native to high altitudes of 3700, 4500, and 5100?m were significantly decreased when compared with subjects at sea level and compared with sea-level subjects acclimated for 5 days at 3700?m. Conclusions: These results demonstrate that high altitude hypoxia induces damage to neurobehavioral functions, and the long-term deficit in neurobehavioral function was more severe than the short-term changes.
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A minimal number of MELT repeats supports all functions of KNL1 in chromosome segregation.
J. Cell. Sci.
PUBLISHED: 12-20-2013
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The Bub1-Bub3 and BubR1-Bub3 checkpoint complexes, or the Bubs, contribute to the accurate segregation of chromosomes during mitosis by promoting chromosome bi-orientation and halting exit from mitosis if this fails. The complexes associate with kinetochores during mitosis, which is required for proper chromosome segregation. The outer kinetochore protein KNL1 (also known as CASC5/Blinkin/AF15Q14) is the receptor for Bub proteins but the exact nature of the functional binding sites on KNL1 are yet to be determined. Here, we show that KNL1 contains multiple binding sites for the Bub proteins, with the Mps1-phosphorylated MELT repeats constituting individual functional docking sites for direct binding of Bub3. Surprisingly, chromosome congression and the Spindle Assembly Checkpoint (SAC) are still functional when KNL1 is deleted of all but four of its twelve MELT repeats. Systematically reducing the number of MELT repeats to less than four reduced KNL1 functionality. Furthermore, we show that Protein Phosphatase 1 (PP1) binding to KNL1 in prometaphase reduces the levels of Bub proteins at kinetochores to approximately the level recruited by four active MELT repeats.
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Characterization of a multi-resistant mosaic plasmid from a fish farm sediment Exiguobacterium sp. isolate reveals aggregation of functional clinically-associated antibiotic resistance genes.
Appl. Environ. Microbiol.
PUBLISHED: 12-20-2013
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The genus Exiguobacterium can adapt readily to, and survive in, diverse environments. Our study demonstrated that Exiguobacterium sp. S3-2 isolated from marine sediment was resistant to five antibiotics. The plasmid pMC1 in the strain carried seven putative resistance genes. We functionally characterized these resistance genes in Escherichia coli, and genes encoding dihydrofolate reductase and macrolide phosphotransferase were considered novel resistance genes based on their low similarities with known resistance genes. The plasmid G+C content distribution was highly heterogeneous. Only the G+C content of one block which shared significant similarity with plasmid from Exiguobacterium arabatum, fit well with the mean G+C content of the host. The remainder of the plasmid was composed of mobile elements with a markedly lower G+C ratio than the host. Interestingly, five mobile elements located on pMC1 showed significant similarities to sequences found in pathogens. Our data provided example for the link of resistance genes between the environment and the clinic and revealed aggregation antibiotic resistance genes in bacteria isolated from fish farm.
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Complete Genome Sequence of Streptococcus pneumoniae Strain A026, a Clinical Multidrug-Resistant Isolate Carrying Tn2010.
Genome Announc
PUBLISHED: 12-17-2013
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Streptococcus pneumoniae is a primary cause of bacterial infection in humans. Here, we present the complete genome sequence of S. pneumoniae strain A026, which is a multidrug-resistant strain isolated from cerebrospinal fluid.
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[Effects of long-term manure and crop residues incorporation on yield and phosphorus saturation in a paddy soil].
Huan Jing Ke Xue
PUBLISHED: 11-07-2013
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An 8-year field experiment was conducted in the Taihu Lake region of eastern China to investigate the effects of incorporation of straw and manure on the yield and phosphorus (P) accumulation in the paddy soil, and to evaluate the potential risk of P loss from soil to environment. The experiment had four fertilization treatments, i. e., chemical fertilizers alone (NPK), chemical fertilizers plus rice/wheat straw (NPK + S), chemical fertilizers plus 7.5 t x (hm2 x a)(-1) wet pig manure (NPK + M7.5), and chemical fertilizers plus 15.0 t x (hm2 x a)(-1) wet pig manure (NPK + M15). Among the four treatments, no significant differences were observed in the yield of rice or wheat. Long-term application of chemical fertilizers plus pig manure significantly increased the soil total P, the degree of P saturation (DPS), and the concentration of extractable P forms, including Olsen-P, Mehlich 3 extractable P, CaCl2 extractable P, and water extractable P, which became a potential source of eutrophication in Taihu Lake. In contrast to chemical fertilizers plus pig manure, there were no significant differences in the concentrations of extractable P forms between the NPK + S and NPK treatments. We concludes that chemical fertilizers [P 45 kg x (hm2 x a)(-1)] plus rice/wheat straw should be recommended in the paddy soil in the Taihu Lake region under the rice-wheat rotation system.
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[Effects of maternal exposure to nano-alumina during pregnancy on neurodevelopment in offspring mice].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 10-24-2013
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To observe the effects of maternal exposure to nano-alumina during pregnancy on the neurodevelopment in offspring mice.
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Axonal degeneration in dorsal columns of spinal cord does not induce recruitment of hematogenous macrophages.
Exp. Neurol.
PUBLISHED: 10-17-2013
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It is generally accepted that there are two populations of macrophages that respond to neural injuries and successful recruitment of hematogenous macrophages has been shown to help the process of nerve repair in the peripheral nervous system (PNS). Meanwhile, the recruitment of circulating macrophages after central nerve system (CNS) injuries is considered mild and delayed. We compared the recruitment of circulating macrophages in the peripheral nerves and spinal cord after dorsal root ganglionectomies, which induce selective and approximately similar extent of sensory fiber degeneration in PNS and CNS, in bone marrow chimeric mice. Our results showed that circulating macrophages were efficiently recruited in PNS but virtually no recruitment in CNS despite degeneration of peripheral and central sensory projections emanating from the same dorsal root ganglion (DRG) neurons. The mechanisms that prevent recruitment of circulating macrophages in CNS after injury remain poorly elucidated.
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Polyhydroxylated Steroids from the South China Sea Soft Coral Sarcophyton sp. and Their Cytotoxic and Antiviral Activities.
Mar Drugs
PUBLISHED: 10-15-2013
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Chemical investigation on the soft coral Sarcophyton sp. collected from the South China Sea yielded three new polyhydroxylated steroids, compounds (1-3), together with seven known ones (4-10). Their structures were established by extensive spectroscopic methods and comparison of their data with those of the related known compounds. All the isolates possessed the 3?,5?,6?-trihydroxylated steroidal nucleus. The cytotoxicities against selected HL-60, HeLa and K562 tumor cell lines and anti-H1N1 (Influenza A virus (IAV)) activities for the isolates were evaluated. Compounds 2, 3 and 5-8 exhibited potent activities against K562 cell lines with IC50 values ranging from 6.4 to 10.3 ?M. Compounds 1, 6-8 potently inhibited the growth of HL-60 tumor cell lines, and 6 also showed cytotoxicity towards HeLa cell lines. In addition, preliminary structure-activity relationships for the isolates are discussed. The OAc group at C-11 is proposed to be an important pharmacophore for their cytotoxicities in the 3?,5?,6?-triol steroids. Compounds 4 and 9 exhibited significant anti-H1N1 IAV activity with IC50 values of 19.6 and 36.7 ?g/mL, respectively.
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Polymerization-induced spinodal decomposition of ethylene glycol?phenolic resin solutions under electric fields.
J Chem Phys
PUBLISHED: 10-15-2013
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Temporal evolution of polymerization-induced spinodal decomposition (PISD) under electric fields was investigated numerically in ethylene glycol?phenolic resin solutions with different initial composition. A model composed of the nonlinear Cahn-Hilliard-Cook equation for spinodal decomposition and a rate equation for curing reaction was utilized to describe the PISD phenomenon. As initial composition varied, deformed droplet-like and aligned bi-continuous structures were observed in the presence of an electric field. Moreover, the anisotropic parameter (D), determined from the 2D-FFT power spectrum, was employed to quantitatively characterize the degree of morphology anisotropy. The value of D increased quickly in the early stage and then decreased in the intermediate stage of spinodal decomposition, which was attributed to the resistance of coarsening process to morphology deformation and the decline of electric stress caused by polymerization reaction. The results can also provide a guidance on how to control the morphology of monolithic porous polymer and carbon materials with anisotropic structures.
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Hypoxia-inducible factor 1 alpha (HIF-1?) as a prognostic indicator in patients with gastric tumors: a meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 09-03-2013
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Though researched for years, the prognostic role of hypoxia-inducible factor 1 alpha (HIF-1?) in gastric cancer is still controversial. We thus undertook a systematic review to assess the relationship.
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[Molecular cloning and characterization of S-adenosyl-L-methionine decarboxylase gene (DoSAMDC1) in Dendrobium officinale].
Yao Xue Xue Bao
PUBLISHED: 08-30-2013
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S-Adenosyl-L-methionine decarboxylase (SAMDC) is a key enzyme in the polyamines biosynthesis, thus is essential for basic physiological and biochemical processes in plant. In the present study, a full length cDNA of DoSAMDC1 gene was obtained from symbiotic germinated seeds of an endangered medicinal orchid species Dendrobium officinale, using the rapid amplification of cDNA ends (RACE)-PCR technique for the first time. The full length cDNA was 1 979 bp, with three open reading frames, i.e. tiny-uORF, small-uORF and main ORF (mORF). The mORF was deduced to encode a 368 amino acid (aa) protein with a molecular mass of 40.7 kD and a theoretical isoelectric point of 5.2. The deduced DoSAMDC1 protein, without signal peptide, had two highly conserved function domains (proenzyme cleavage site and PEST domain) and a 22-aa transmembrane domain (89-110). Multiple sequence alignments and phylogenetic relationship analyses revealed DoSAMDC1 had a higher level of sequence similarity to monocot SAMDCs than those of dicot. Expression patterns using qRT-PCR analyses showed that DoSAMDC1 transcripts were expressed constitutively without significant change in the five tissues (not infected with fungi). While in the symbiotic germinated seeds, the expression level was enhanced by 2.74 fold over that in the none-germinated seeds, indicating possible involvement of the gene in symbiotic seed germination of D. officinale.
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Golden plaster for pain therapy in patients with knee osteoarthritis: study protocol for a multicenter randomized, double-blind, placebo-controlled trial.
Trials
PUBLISHED: 08-29-2013
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Osteoarthritis is a relatively common musculoskeletal disorder that increases in prevalence with age. Worldwide, knee osteoarthritis is one of the leading causes of disability, particularly in the elderly. In numerous trials of agents for long-term pain therapy, no well-established and replicable results have been achieved. Complementary and alternative medical approaches have been employed for thousands of years to relieve knee osteoarthritis pain. Among herbal medicines, the golden plaster is the preferred and most commonlyused method in China to reduce pain inpatients with knee osteoarthritis, as it causes few adverse effects. The purpose of this study will be to evaluate the efficacy and safety of golden plaster on pain in patients with knee osteoarthritis.Methods/design: This study will be a multicenter randomized, double-blind, placebo-controlled trial. A total of 320 participants aged 45 to 79 years with knee osteoarthritis, whose scores on a visual analog scale (VAS) are more than 20 mm,will be randomly allocated into a treatment group and a control group. A golden plaster will be administered externally to participants in the treatment group for 2 weeks, while the control group will receive a placebo plaster externally for 2 weeks. Follow-up will be at regular intervals during a 4-week period with a VAS score for pain, quality of life, and complications.
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MicroRNAs-449a and -449b exhibit tumor suppressive effects in retinoblastoma.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-27-2013
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Retinoblastoma is the most common pediatric cancer of the eye. Currently, the chemotherapeutic treatments for retinoblastoma are broad-based drugs such as vincristine, carboplatin, or etoposide. However, therapies targeted directly to aberrant signaling pathways may provide more effective therapy for this disease. The purpose of our study is to illustrate the relationship between the expressions of miRs-449a and -449b to retinoblastoma proliferation and apoptosis. We are the first to confirm an inhibitory effect of miR-449a and -449b in retinoblastoma by demonstrating significantly impaired proliferation and increased apoptosis of tumor cells when these miRNAs are overexpressed. This study suggests that these miRNAs could serve as viable therapeutic targets for retinoblastoma treatment.
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[Long-term outcomes and factors for predicting ventricular arrhythmia in patients with catecholaminergic polymorphic ventricular tachycardia].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 08-23-2013
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To evaluate factors for predicting ventricular arrhythmia, the clinical effect of drugs on patients with catecholaminergic polymorphic ventricular tachycardia (CPVT), and their long-term outcomes.
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Identification of two novel anti-fibrotic benzopyran compounds produced by engineered strains derived from Streptomyces xiamenensis M1-94P that originated from deep-sea sediments.
Mar Drugs
PUBLISHED: 08-17-2013
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The benzopyran compound obtained by cultivating a mangrove-derived strain, Streptomyces xiamenensis strain 318, shows multiple biological effects, including anti-fibrotic and anti-hypertrophic scar properties. To increase the diversity in the structures of the available benzopyrans, by means of biosynthesis, the strain was screened for spontaneous rifampicin resistance (Rif), and a mutated rpsL gene to confer streptomycin resistance (Str), was introduced into the S. xiamenensis strain M1-94P that originated from deep-sea sediments. Two new benzopyran derivatives, named xiamenmycin C (1) and D (2), were isolated from the crude extracts of a selected Str-Rif double mutant (M6) of M1-94P. The structures of 1 and 2 were identified by analyzing extensive spectroscopic data. Compounds 1 and 2 both inhibit the proliferation of human lung fibroblasts (WI26), and 1 exhibits better anti-fibrotic activity than xiamenmycin. Our study presents the novel bioactive compounds isolated from S. xiamenensis mutant strain M6 constructed by ribosome engineering, which could be a useful approach in the discovery of new anti-fibrotic compounds.
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[Status of household disaster preparedness and affecting factors among the general public of four counties in Shaanxi].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 08-10-2013
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To investigate the status of household disaster preparedness in 4 counties of Shaanxi province and explore the affecting factors.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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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.