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.
Diastereo- and enantioselective iridium-catalyzed allylation of cyclic ketone enolates: synergetic effect of ligands and barium enolates.
J. Am. Chem. Soc.
PUBLISHED: 10-30-2014
Show Abstract
Hide Abstract
We report asymmetric allylic alkylation of barium enolates of cyclic ketones catalyzed by a metallacyclic iridium complex containing a phosphoramidite ligand derived from (R)-1-(2-naphthyl)ethylamine. The reaction products contain adjacent quaternary and tertiary stereocenters. This process demonstrates that unstabilized cyclic ketone enolates can undergo diastereo- and enantioselective Ir-catalyzed allylic substitution reactions with the proper choice of enolate countercation. The products of these reactions can be conveniently transformed to various useful polycarbocyclic structures.
Related JoVE Video
Surface functionalization of semiconductor and oxide nanocrystals with small inorganic oxoanions (PO4(3-), MoO4(2-)) and polyoxometalate ligands.
ACS Nano
PUBLISHED: 09-02-2014
Show Abstract
Hide Abstract
In this work, we study the functionalization of the nanocrystal (NC) surface with inorganic oxo ligands, which bring a new set of functionalities to all-inorganic colloidal nanomaterials. We show that simple inorganic oxoanions, such as PO4(3-) and MoO4(2-), exhibit strong binding affinity to the surface of various II-VI and III-V semiconductor and metal oxide NCs. ?-Potential titration offered a useful tool to differentiate the binding affinities of inorganic ligands toward different NCs. Direct comparison of the binding affinity of oxo and chalcogenidometallate ligands revealed that the former ligands form a stronger bond with oxide NCs (e.g., Fe2O3, ZnO, and TiO2), while the latter prefer binding to metal chalcogenide NCs (e.g., CdSe). The binding between NCs and oxo ligands strengthens when moving from small oxoanions to polyoxometallates (POMs). We also show that small oxo ligands and POMs make it possible to tailor NC properties. For example, we observed improved stability upon Li(+)-ion intercalation into the films of Fe2O3 hollow NCs when capped with MoO4(2-) ligands. We also observed lower overpotential and enhanced exchange current density for water oxidation using Fe2O3 NCs capped with [P2Mo18O62](6-) ligands and even more so for [{Ru4O4(OH)2(H2O)4}(?-SiW10O36)2] with POM as the capping ligand.
Related JoVE Video
Redox regulation of cancer metastasis: molecular signaling and therapeutic opportunities.
Drug Dev. Res.
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
Cancer metastasis is the major cause of cancer-related mortality. Accumulated evidence has shown that high-metastasis potential cancer cells have more reactive oxygen species (ROS) accumulation compared with low-metastasis potential cancer cells. ROS can function as second messengers to regulate multiple cancer metastasis-related signaling pathways via reversible oxidative posttranslational modifications of cysteine in key redox-sensitive proteins, which leads to the structural and functional change of these proteins. Because ROS can promote cancer metastasis, therapeutic strategies aiming at inducing/reducing cellular ROS level or targeting redox sensors involved in metastasis hold great potential in developing new efficient approaches for anticancer therapy. In this review, we summarize recent findings on regulation of tumor metastasis by key redox sensors and describe the potential of targeting redox signaling pathways for cancer therapy.
Related JoVE Video
The geostatistic-based spatial distribution variations of soil salts under long-term wastewater irrigation.
Environ Monit Assess
PUBLISHED: 08-17-2014
Show Abstract
Hide Abstract
The purpose of this study was to determine and evaluate the spatial changes in soil salinity by using geostatistical methods. The study focused on the suburb area of Beijing, where urban development led to water shortage and accelerated wastewater reuse to farm irrigation for more than 30 years. The data were then processed by GIS using three different interpolation techniques of ordinary kriging (OK), disjunctive kriging (DK), and universal kriging (UK). The normality test and overall trend analysis were applied for each interpolation technique to select the best fitted model for soil parameters. Results showed that OK was suitable for soil sodium adsorption ratio (SAR) and Na(+) interpolation; UK was suitable for soil Cl(-) and pH; DK was suitable for soil Ca(2+). The nugget-to-sill ratio was applied to evaluate the effects of structural and stochastic factors. The maps showed that the areas of non-saline soil and slight salinity soil accounted for 6.39 and 93.61%, respectively. The spatial distribution and accumulation of soil salt were significantly affected by the irrigation probabilities and drainage situation under long-term wastewater irrigation.
Related JoVE Video
Carrier dynamics in highly quantum-confined, colloidal indium antimonide nanocrystals.
ACS Nano
PUBLISHED: 08-14-2014
Show Abstract
Hide Abstract
Nanometer-sized particles of indium antimonide (InSb) offer opportunities in areas such as solar energy conversion and single photon sources. Here, we measure electron-hole pair dynamics, spectra, and absorption cross sections of strongly quantum-confined colloidal InSb nanocrystal quantum dots using femtosecond transient absorption. For all samples, we observe a bleach feature that develops on ultrafast time scales, which notably moves to lower energy during the first several picoseconds following excitation. We associate this unusual red shift, which becomes larger for larger particles and more distinct at lower sample temperatures, with hot exciton cooling through states that we suggest arise from energetically proximal conduction band levels. From controlled optical excitation intensities, we determine biexciton lifetimes, which range from 2 to 20 ps for the studied 3-6 nm diameter particle sizes.
Related JoVE Video
Effect of compressed sensing reconstruction on target and organ delineation in cone-beam CT of head-and-neck and breast cancer patients.
Radiother Oncol
PUBLISHED: 08-04-2014
Show Abstract
Hide Abstract
Compressed sensing (CS) based cone-beam computed tomography (CBCT) reconstruction techniques have been shown to improve image quality. This study was to investigate possible improvements of CBCTCS on manual delineation uncertainties of targets and organs-at-risk.
Related JoVE Video
Predictive value of cystic fibrosis transmembrane conductance regulator (CFTR) in the diagnosis of gastric cancer.
Clin Invest Med
PUBLISHED: 08-04-2014
Show Abstract
Hide Abstract
Gastric cancer is associated with poor prognosis. The high mortality rate of gastric cancer is mainly attributed to late detection, so diagnosis and treatment are crucial to decreasing mortality. The purpose of this study was to examine the predictive accuracy and discriminative ability of cystic fibrosis transmembrane conductance regulator (CFTR) in gastric cancer patients, in addition to the classical cancer tumor biomarkers carbohydrate antigen 199 (CA199) and carcinoembryonic antigen (CEA).
Related JoVE Video
Paclitaxel- and/or cisplatin-induced ocular neurotoxicity: a case report and literature review.
Onco Targets Ther
PUBLISHED: 07-31-2014
Show Abstract
Hide Abstract
Paclitaxel (PTX) and/or cisplatin (CDDP), as important cytotoxic anti-cancer agents, are widely used to treat various solid tumors. Both may cause moderate or severe neurotoxicity, but ocular neurotoxicity is also occasionally reported. A patient diagnosed with nasopharyngeal cancer suffering acute ocular neurotoxicity 10 days after paclitaxel and CDDP administration at the recommended dose is described in the present case report, and PTX- and/or CDDP-induced ocular neurotoxicity are summarized according to previous reports. Possible mechanisms and the potential diagnostic, therapeutic and predictive strategies of PTX- and/or CDDP-induced ocular neurotoxicity are reviewed, to help the oncologist to take the infrequent toxicity of cytotoxic drugs into account and improve patient safety during anti-cancer therapy.
Related JoVE Video
Colloidal nanocrystals with inorganic halide, pseudohalide, and halometallate ligands.
ACS Nano
PUBLISHED: 07-08-2014
Show Abstract
Hide Abstract
We investigate simple halides and pseudohalides as an important class of inorganic ligands for nanocrystals (NCs) in solution phase ligand exchange. These short, robust, and easy to model ligands bind to the NC surface and provide electrostatic stabilization of NC dispersions in N-methylformamide. The replacement of organic ligands on NCs with compact halide and pseudohalide ligands greatly facilitates electronic communication between NCs. For example, a high electron mobility of ? ? 12 cm(2) V(-1) s(-1) has been observed in thin films made of I(-)-capped CdSe NCs. We also studied charge transport properties of thin films based on the pseudohalide N3(-)-capped InAs NCs, suggesting the possibility of obtaining "all III-V" NC solids. In addition, we extend the surface chemistry of halometallates (e.g., CH3NH3PbI3), which can stabilize colloidal solutions of lead chalcogenide NCs. These halide, pseudohalide, and halometallate ligands enrich the current family of inorganic ligands and can open up more opportunities for applications of NCs in the fields of electronics, optoelectronics, and thermoelectrics.
Related JoVE Video
Nerve Regeneration and Functional Recovery by Collagen-Binding Brain-Derived Neurotrophic Factor in an Intracerebral Hemorrhage Model.
Tissue Eng Part A
PUBLISHED: 06-20-2014
Show Abstract
Hide Abstract
Brain-derived neurotrophic factor (BDNF) exerts therapeutic effects following intracerebral hemorrhage (ICH). However, it is difficult to maintain sufficient concentrations in the hemorrhage hemisphere. We demonstrated previously that BDNF fused to a collagen-binding domain (CBD) could bind to collagen in the ventricular ependyma and stimulate cell proliferation in the subventricular zone (SVZ). In this study, we verified the therapeutic effects of CBD-BDNF in the rat ICH model induced by bacterial collagenase by injecting CBD-BDNF into the lateral ventricle of ICH rats. The results demonstrated that CBD-BDNF was retained at high levels in the hemorrhage hemisphere, where it promoted neural regeneration and angiogenesis, reduced tissue loss, and improved functional recovery.
Related JoVE Video
Expression and regulation of INTELECTIN1 in human granulosa-lutein cells: role in IGF-1-induced steroidogenesis through NAMPT.
Biol. Reprod.
PUBLISHED: 06-18-2014
Show Abstract
Hide Abstract
INTELECTIN (ITLN) is an adipokine involved in the regulation of insulin sensitivity and inflammatory and immunity responses. Serum ITLN levels are lower in obese, diabetic, and polycystic ovary syndrome (PCOS) women than in control subjects. ITLN has never been studied in ovarian cells. Here, we identified ITLN1 in human ovarian follicles and investigated the molecular mechanisms involved in the regulation of its expression in response to the insulin sensitizers metformin and rosiglitazone, in human granulosa-lutein cells (hGLCs) and in a human ovarian granulosa-like tumor cell line (KGN). We also studied the effects of human recombinant ITLN1 (hRom1) on steroid production and on the activation of various signaling pathways. Using RT-PCR, immunoblotting, and immunohistochemistry, we found that INTL1 is present in human follicular cells. Using ELISA, we showed that INTL levels are similar in plasma and follicular fluid (FF) in control patients, whereas they are higher in FF than in plasma in PCOS patients. In KGN cells and hGLCs, insulin (10(-8) M), insulin-like growth factor-1 (IGF-1; 10(-8) M), and metformin (10(-2) M or 10(-3) M) increased INTL1 expression (mRNA and protein) after 12 and 24 h of stimulation. For metformin, this effect was mediated by adenosine monophosphate-activated kinase (PRKA). Furthermore, hRom1 increased nicotinamide phosphoribosyltransferase (NAMPT) expression in KGN and hGLCs. We also showed that hRom1 increased IGF-1-induced progesterone and estradiol secretion and this was associated with an increase in the STAR and CYP19A1 protein levels and an increase in IGF-1R signaling. Furthermore, all these data were abolished when NAMPT was knocked down in KGN cells, suggesting that INTL1 improves IGF-1-induced steroidogenesis through induction of NAMPT in hGLCs.
Related JoVE Video
ATRA-induced cellular differentiation and CD38 expression inhibits acquisition of BCR-ABL mutations for CML acquired resistance.
PLoS Genet.
PUBLISHED: 06-01-2014
Show Abstract
Hide Abstract
Acquired resistance through genetic mutations is a major obstacle in targeted cancer therapy, but the underlying mechanisms are poorly understood. Here we studied mechanisms of acquired resistance of chronic myeloid leukemia (CML) to tyrosine kinase inhibitors (TKIs) by examining genome-wide gene expression changes in KCL-22 CML cells versus their resistant KCL-22M cells that acquire T315I BCR-ABL mutation following TKI exposure. Although T315I BCR-ABL is sufficient to confer resistance to TKIs in CML cells, surprisingly we found that multiple drug resistance pathways were activated in KCL-22M cells along with reduced expression of a set of myeloid differentiation genes. Forced myeloid differentiation by all-trans-retinoic acid (ATRA) effectively blocked acquisition of BCR-ABL mutations and resistance to the TKIs imatinib, nilotinib or dasatinib in our previously described in vitro models of acquired TKI resistance. ATRA induced robust expression of CD38, a cell surface marker and cellular NADase. High levels of CD38 reduced intracellular nicotinamide adenine dinucleotide (NAD+) levels and blocked acquired resistance by inhibiting the activity of the NAD+-dependent SIRT1 deacetylase that we have previously shown to promote resistance in CML cells by facilitating error-prone DNA damage repair. Consequently, ATRA treatment decreased DNA damage repair and suppressed acquisition of BCR-ABL mutations. This study sheds novel insight into mechanisms underlying acquired resistance in CML, and suggests potential benefit of combining ATRA with TKIs in treating CML, particularly in advanced phases.
Related JoVE Video
Methods for detecting transcribed pseudogenes: PCR on regions of high sequence similarity followed by cloning and sequencing.
Methods Mol. Biol.
PUBLISHED: 05-15-2014
Show Abstract
Hide Abstract
Identifying pseudogene transcription is problematic in many cases due to the high sequence similarity between pseudogenes and their parental genes. In this chapter, we detail the procedure for the detection of pseudogene transcription using the reverse transcription polymerase chain reaction (RT-PCR) method. The protocol comprises (1) extraction of total RNA, (2) first-strand cDNA synthesis from total RNA, (3) amplification of the cDNA by PCR, and (4) cloning and sequencing of the PCR products. Technical and practical guidance is provided, and the critical points during each of the steps are discussed. In particular, the importance of designing high specific PCR primers and thoroughly eliminating genomic DNA contamination from RNA preparation is emphasized.
Related JoVE Video
Curcumin inhibits the invasion of thyroid cancer cells via down-regulation of PI3K/Akt signaling pathway.
Gene
PUBLISHED: 04-11-2014
Show Abstract
Hide Abstract
The objectives of this study were to evaluate the in vitro anti-tumor (human thyroid cancer cell lines) potential of curcumin and to elucidate its molecular mechanisms. Here, we investigated the effects of curcumin on the cell viability, apoptosis, migration and invasion of human thyroid cancer cell lines FTC133. We also investigated the effects of curcumin on PI3K, p-Akt, MMP1/7, and COX-2 protein expressions using Western blot. Results showed that curcumin inhibited growth, cell migration and invasion in FTC133, and promoted its apoptosis. Western blot assay data demonstrated that curcumin inhibited phosphorylation of PI3K and Akt signaling pathways and subsequently attenuated MMP1/7 and COX-2 protein expressions in FTC133. In conclusion, curcumin suppresses FTC133 cell invasion and migration by inhibiting PI3K and Akt signaling pathways. Therefore, curcumin produces anti-metastatic activity in FTC133 cells.
Related JoVE Video
Collagen scaffolds modified with CNTF and bFGF promote facial nerve regeneration in minipigs.
Biomaterials
PUBLISHED: 04-10-2014
Show Abstract
Hide Abstract
Most experiments of peripheral nerve repair after injury have been conducted in the rodent model but the translation of findings from rodent studies to clinical practice is needed partly because the nerve regeneration must occur over much longer distances in humans than in rodents. The reconstruction of long distance nerve injuries still represents a great challenge to surgeons who is engaged in peripheral nerve surgery. Here we used the functional nerve conduit (collagen scaffolds incorporated with neurocytokines CNTF and bFGF) to bridge a 35 mm long facial nerve gap in minipig models. At 6 months after surgery, electrophysiology assessment and histological examination were conducted to evaluate the regeneration of peripheral facial nerves. Based on functional and histological observations, the results indicated that the functional collagen scaffolds promoted nerve reconstruction. The number and arrangement of regenerated nerve fibers, myelination, and nerve function reconstruction was better in the CNTF + bFGF conduit group than the single factor CNTF or bFGF conduit group. The functional composite conduit, which exhibited favorable mechanical properties, may promote facial nerve regeneration in minipigs effectively.
Related JoVE Video
The effect of platform switching on stress distribution in implants and periimplant bone studied by nonlinear finite element analysis.
J Prosthet Dent
PUBLISHED: 04-05-2014
Show Abstract
Hide Abstract
It is unknown whether dental implant systems with a platform-switched configuration have better periimplant bone stress distribution and lead to less periimplant bone level changes.
Related JoVE Video
Multiple-beam output of a surface-emitted terahertz-wave parametric oscillator by using a slab MgO:LiNbO? crystal.
Opt Lett
PUBLISHED: 02-25-2014
Show Abstract
Hide Abstract
A MgO:LiNbO? slab configuration for the surface-emitted terahertz-wave parametric oscillator (TPO) is presented. The pump and the oscillating Stokes beams were totally reflected at the slab surface and propagated zigzaggedly in the slab MgO:LiNbO? crystal. Up to five terahertz beams were emitted perpendicularly to the surface of the crystal. The total output energy of the five THz-wave beams was 3.56 times as large as that obtained from the conventional surface-emitted TPO at the same experimental conditions. The intensity distributions of the THz wave beams were measured, and they were unsymmetrical in the horizontal direction while symmetrical in the vertical direction.
Related JoVE Video
Effect of Th17 and Treg axis disorder on outcomes of pulmonary arterial hypertension in connective tissue diseases.
Mediators Inflamm.
PUBLISHED: 02-22-2014
Show Abstract
Hide Abstract
This prospective cohort study is to verify the hypothesis that the balance of Th17 and Treg cells frequencies in the peripheral circulation is disturbed in patients with varying degrees of connective tissue diseases-associated pulmonary arterial hypertension (CTD-aPAH) and to prove the influence of Th17/Treg imbalance on prognosis. We detected the frequencies and absolute counts of Th17 and Treg cells and related serum cytokines secretion and expressions of key transcription factors in 117 patients with connective tissue diseases (CTD), 53 patients with CTD-aPAH, and 48 healthy volunteers. Moreover, the median value according to levels of Th17/Treg ratios in patients with CTD-aPAH was chosen as basis of group division for survival analysis. CTD-aPAH patients revealed significant increase in peripheral Th17 cells, Th17-related cytokines, and ROR ?t mRNA levels. They also presented a significant decrease in Treg cells, Treg-related cytokines, and Foxp3 mRNA levels as compared with CTD patients and healthy controls. More importantly, the Th17/Treg ratio was significantly related to the severity and prognosis of CTD-aPAH. This study indicated that the Th17/Treg axis disorder plays a critical role in CTD-aPAH. Furthermore, the dynamic balance between Th17 and Treg cells was likely to influence prognosis of patients with CTD-aPAH.
Related JoVE Video
Recent progress in metal-organic complexes for optoelectronic applications.
Chem Soc Rev
PUBLISHED: 02-17-2014
Show Abstract
Hide Abstract
The design and characterization of metal-organic complexes for optoelectronic applications is an active area of research. The metal-organic complex offers unique optical and electronic properties arising from the interplay between the inorganic metal and the organic ligand. The ability to modify chemical structure through control over metal-ligand interaction on a molecular level could directly impact the properties of the complex. When deposited in thin film form, this class of materials enable the fabrication of a wide variety of low-cost electronic and optoelectronic devices. These include light emitting diodes, solar cells, photodetectors, field-effect transistors as well as chemical and biological sensors. Here we present an overview of recent development in metal-organic complexes with controlled molecular structures and tunable properties. Advances in extending the control of molecular structures to solid materials for energy conversion and information technology applications will be highlighted.
Related JoVE Video
Efficient hydrolysis of cellulose over a novel sucralose-derived solid acid with cellulose-binding and catalytic sites.
J. Agric. Food Chem.
PUBLISHED: 02-17-2014
Show Abstract
Hide Abstract
A new sucralose-derived solid acid catalyst (SUCRA-SO3H), containing -Cl and -SO3H functional groups, has been shown to be highly effective for hydrolyzing ?-1,4-glucans, completely hydrolyzing cellobiose (1) into glucose (2) in 3 h and converting the microcrystalline cellulose pretreated by the ionic liquid into glucose (2) with a yield of around 55% and a selectivity of 98% within 24 h at a relatively moderate temperature (393K). The enhanced adsorption capacity that the catalyst has for glucan by virtue of the presence of chloride groups that act as cellulose-binding sites offers the possibility of resolving the existing bottleneck in heterogeneous catalysis to hydrolyze cellulose, namely, the low accessibility of cellulose to the reaction position in typical solid catalysts. The apparent activation energy for hydrolysis of cellobiose (1) with SUCRA-SO3H was 94 kJ/mol, which was much lower than that with sulfuric acid (133 kJ/mol) and the corresponding sucrose-derived catalyst (SUCRO-SO3H) without chlorine groups (114 kJ/mol).
Related JoVE Video
SIRT1 activation by a c-MYC oncogenic network promotes the maintenance and drug resistance of human FLT3-ITD acute Myeloid Leukemia stem cells.
Cell Stem Cell
PUBLISHED: 02-04-2014
Show Abstract
Hide Abstract
The FLT3-ITD mutation is frequently observed in acute myeloid leukemia (AML) and is associated with poor prognosis. In such patients, FLT3 tyrosine kinase inhibitors (TKIs) are only partially effective and do not eliminate the leukemia stem cells (LSCs) that are assumed to be the source of treatment failure. Here, we show that the NAD-dependent SIRT1 deacetylase is selectively overexpressed in primary human FLT3-ITD AML LSCs. This SIRT1 overexpression is related to enhanced expression of the USP22 deubiquitinase induced by c-MYC, leading to reduced SIRT1 ubiquitination and enhanced stability. Inhibition of SIRT1 expression or activity reduced the growth of FLT3-ITD AML LSCs and significantly enhanced TKI-mediated killing of the cells. Therefore, these results identify a c-MYC-related network that enhances SIRT1 protein expression in human FLT3-ITD AML LSCs and contributes to their maintenance. Inhibition of this oncogenic network could be an attractive approach for targeting FLT3-ITD AML LSCs to improve treatment outcomes.
Related JoVE Video
Temperature-dependent Hall and field-effect mobility in strongly coupled all-inorganic nanocrystal arrays.
Nano Lett.
PUBLISHED: 01-30-2014
Show Abstract
Hide Abstract
We report on the temperature-dependent Hall effect characteristics of nanocrystal (NC) arrays prepared from colloidal InAs NCs capped with metal chalcogenide complex (MCC) ligands (In2Se4(2-) and Cu7S4(-)). Our study demonstrates that Hall effect measurements are a powerful way of exploring the fundamental properties of NC solids. We found that solution-cast 5.3 nm InAs NC films capped with copper sulfide MCC ligands exhibited high Hall mobility values over 16 cm(2)/(V s). We also showed that the nature of MCC ligands can control doping in NC solids. The comparative study of the temperature-dependent Hall and field-effect mobility values provides valuable insights concerning the charge transport mechanism and points to the transition from a weak to a strong coupling regime in all-inorganic InAs NC solids.
Related JoVE Video
Immunoproteomic to analysis the pathogenicity factors in leukopenia caused by Klebsiella pneumonia bacteremia.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Incidences of leukopenia caused by bacteremia have increased significantly and it is associated with prolonged hospital stay and increased cost. Immunoproteomic is a promising method to identify pathogenicity factors of different diseases. In the present study, we used immunoproteomic to analysis the pathogenicity factors in leukopenia caused by Klebsiella Pneumonia bacteremia. Approximately 40 protein spots localized in the 4 to 7 pI range were detected on two-dimensional electrophoresis gels, and 6 differentially expressed protein spots between 10 and 170 kDa were identified. Pathogenicity factors including S-adenosylmethionine synthetase, pyruvate dehydrogenase, glutathione synthetase, UDP-galactose-4-epimerase, acetate kinase A and elongation factor tu (EF-Tu). In validation of the pathogenicity factor, we used western blotting to show that Klebsiella pneumonia had higher (EF-Tu) expression when they accompanied by leukopenia rather than leukocytosis. Thus, we report 6 pathogenicity factors of leukopenia caused by Klebsiella pneumonia bacteremia, including 5 housekeeping enzymes and EF-Tu. We suggest EF-Tu could be a potential pathogenicity factor for leukopenia caused by Klebsiella pneumonia.
Related JoVE Video
Meta-analysis of the association between lumican gene polymorphisms and susceptibility to high Myopia.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Many studies have evaluated the association between lumican (LUM) gene polymorphisms and high myopia. However, the results remain controversial. This meta-analysis aims to comprehensively evaluate the relationship between two common LUM polymorphisms (rs3759223 and rs3759222) and the risk of high myopia.
Related JoVE Video
Evaluation of the dosimetric feasibility of hippocampal sparing intensity-modulated radiotherapy in patients with locally advanced nasopharyngeal carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The objective of this study was to evaluate the dosimetric feasibility of using hippocampus (HPC) sparing intensity-modulated radiotherapy (IMRT) in patients with locally advanced nasopharyngeal carcinoma (NPC).
Related JoVE Video
Ologen implant versus mitomycin C for trabeculectomy: a systematic review and meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
To evaluate the application of the Ologen implant compared to mitomycin C (MMC) on the outcome of trabeculectomy and to examine the balance of risks and benefits.
Related JoVE Video
Thermal Stability of Colloidal InP Nanocrystals: Small Inorganic Ligands Boost High-Temperature Photoluminescence.
ACS Nano
PUBLISHED: 12-23-2013
Show Abstract
Hide Abstract
We examine the stability of excitons in quantum-confined InP nanocrystals as a function of temperature elevation up to 800 K. Through the use of static and time-resolved spectroscopy, we find that small inorganic capping ligands substantially improve the temperature dependent photoluminescence quantum yield relative to native organic ligands and perform similarly to a wide band gap inorganic shell. For this composition, we identify the primary exciton loss mechanism as electron trapping through a combination of transient absorption and transient photoluminescence measurements. Density functional theory indicates little impact of studied inorganic ligands on InP core states, suggesting that reduced thermal degradation relative to organic ligands yields improved stability; this is further supported by a lack of size dependence in photoluminescence quenching, pointing to the dominance of surface processes, and by relative thermal stabilities of the surface passivating media. Thus, small inorganic ligands, which benefit device applications due to improved carrier access, also improve the electronic integrity of the material during elevated temperature operation and subsequent to high temperature material processing.
Related JoVE Video
Cation Control of Diastereoselectivity in Iridium-Catalyzed Allylic Substitutions. Formation of Enantioenriched Tertiary Alcohols and Thioethers by Allylation of 5H-Oxazol-4-ones and 5H-Thiazol-4-ones.
J. Am. Chem. Soc.
PUBLISHED: 12-19-2013
Show Abstract
Hide Abstract
We report highly diastereo- and enantioselective allylations of substituted 5H-oxazol-4-ones and 5H-thiazol-4-ones catalyzed by a metallacyclic iridium complex. Enantioselective Ir-catalyzed allylation of substituted 5H-oxazol-4-ones occurs with high diastereoselectivity by employing the corresponding zinc enolates; enantioselective Ir-catalyzed allylation of substituted 5H-thiazol-4-ones occurs with the corresponding magnesium enolates with high diastereoselectivity. The allylation of substituted 5H-oxazol-4-ones provides rapid access to enantioenriched tertiary ?-hydroxy acid derivatives unavailable through Mo-catalyzed allylic substitution. The allylation of substituted 5H-thiazol-4-ones provides a novel method to synthesize enantioenriched tertiary thiols and thioethers. The observed cation effect implies a novel method to control the diastereoselectivity in Ir-catalyzed allylic substitution.
Related JoVE Video
In vitro short-term bonding performance of zirconia treated with hot acid etching and primer conditioning etching and primer conditioning.
Dent Mater J
PUBLISHED: 11-15-2013
Show Abstract
Hide Abstract
This study aimed to investigate and compare the resin bond strengths of zirconia conditioned as follows: alumina sandblasting; alumina sandblasting+application of 10-MDP-containing primer; alumina sandblasting+application of Z-Prime Plus or Metal/Zirconia Primer (new zirconia primers); tribochemical silica coating+silanization; hot acid etching in three different combinations [H2SO4/(NH4)2SO4, HF/HNO3, H2SO4/HF/HNO3]+application of 10-MDP-containing primer. Shear bond strengths (SBS) after water storage for 24 h and 40 days were measured to assess resin bonding performance. Surface and chemical properties of conditioned zirconia surfaces and primers were characterized using scanning electron microscopy, energy dispersive X-ray spectrometry, Fourier transform infrared spectroscopy, and atomic force microscopy. Surface roughness ranked in descending order was: hot acid etching > tribochemical silica coating > alumina sandblasting. Combination of tribochemical silica coating and silanization showed the highest initial SBS (12.46±2.13 MPa) (P<0.01). Etching with H2SO4/(NH4)2SO4 (13.15±3.24 MPa) and HF/HNO3 (13.48±2.15 MPa) showed significantly better bond durability (P<0.01). Hot acid etching seemed to be a promising surface roughening treatment to improve resin-zirconia bonding.
Related JoVE Video
An all-fiber continuously time-dispersion-tuned picosecond optical parametric oscillator at 1 ?m region.
Opt Express
PUBLISHED: 10-24-2013
Show Abstract
Hide Abstract
We report the experimental demonstration of a fully fiber-integrated picosecond optical parametric oscillator. The gain is provided by a 50-meters homemade photonic crystal fiber in the ring cavity. A time-dispersion-tuned technique is used to allow the oscillator to select the oscillating wavelength adaptively and synchronize with the pump pulse train. The output wavelength of the oscillator can be continuously tuned from 988 to 1046 nm and from 1085 to 1151 nm by adjusting the pump wavelength and the time-dispersion-tuned technique simultaneously.
Related JoVE Video
An evaluation of the effectiveness of novel industrial by-products and organic wastes on heavy metal immobilization in Pb-Zn mine tailings.
Environ Sci Process Impacts
PUBLISHED: 09-24-2013
Show Abstract
Hide Abstract
The in situ immobilization of heavy metals using various easily obtainable amendments is a cost-effective and practical method in the remediation of contaminated sites. In this study, two novel industrial waste materials (sweet sorghum vinasse and medicinal herb residues), spent mushroom compost and municipal solid wastes were used as amendments to assess their potential value for the in situ immobilization of heavy metals in tailings from a Pb-Zn mine in South China. Our results demonstrate that all three freely-available organic wastes decrease the deionized water (DW)- and diethylene-triamine-pentaacetic acid (DTPA)-extractable metal concentrations, enhance the enzyme activity, reduce the metal concentration in plant tissues, and could be used for the remediation of these Pb-Zn mine tailings metals by immobilization. The municipal solid waste failed to reduce the metal concentration in tailings and plant tissues and therefore would not be a suitable immobilizing agent. The potential value of these materials as immobilizers of heavy metals and their remediation efficacy deserve further studies in large-scale field trials.
Related JoVE Video
Emerging Roles of SIRT1 in Cancer Drug Resistance.
Genes Cancer
PUBLISHED: 09-11-2013
Show Abstract
Hide Abstract
Innate resistance to various therapeutic interventions is a hallmark of cancer. In recent years, acquired resistance has emerged as a daunting challenge to targeted cancer therapy, which abolishes the efficacy of otherwise successful targeting drugs. Cancer cells gain the resistance property through a variety of mechanisms in primary and metastatic cancers, involving cellular intrinsic and extrinsic factors. Increasing evidence suggests that the mammalian stress response gene sirtuin 1 (SIRT1) plays a critical role in multiple aspects of cancer drug resistance. SIRT1 decreases drug penetration, confers proliferation and antiapoptotic survival advantages to cancer cells, facilitates acquired resistance through genetic mutations, promotes the survival of cancer stem cells, and changes the tumor microenvironment for resistance in cell-autonomous and -nonautonomous manners. This article provides an overview of research advances in the roles of SIRT1 in cancer drug resistance and highlights the prospect of targeting SIRT1 as a new strategy to overcome cancer drug resistance and improve therapeutic outcomes.
Related JoVE Video
Theoretical investigation of the electron capture and loss processes in the collisions of He2+ + Ne.
J Chem Phys
PUBLISHED: 09-07-2013
Show Abstract
Hide Abstract
Based on the time-dependent density functional theory, a method is developed to study ion-atom collision dynamics, which self-consistently couples the quantum mechanical description of electron dynamics with the classical treatment of the ion motion. Employing real-time and real-space method, the coordinate space translation technique is introduced to allow one to focus on the region of target or projectile depending on the actual concerned process. The benchmark calculations are performed for the collisions of He(2+) + Ne, and the time evolution of electron density distribution is monitored, which provides interesting details of the interaction dynamics between the electrons and ion cores. The cross sections of single and many electron capture and loss have been calculated in the energy range of 1-1000 keV/amu, and the results show a good agreement with the available experiments over a wide range of impact energies.
Related JoVE Video
[Clinical evaluation on aesthetic effect of custom pressable metal ceramic abutment for dental implant restoration in anterior zone].
Hua Xi Kou Qiang Yi Xue Za Zhi
PUBLISHED: 09-03-2013
Show Abstract
Hide Abstract
OBJECTIVE To evaluate the aesthetic effect of restorations with custom pressable metal ceramic abutments for defective soft and hard tissue in the maxillary anterior zone.
Related JoVE Video
Sparing functional anatomical structures during intensity-modulated radiotherapy: an old problem, a new solution.
Future Oncol
PUBLISHED: 08-29-2013
Show Abstract
Hide Abstract
During intensity-modulated radiotherapy, an organ is usually assumed to be functionally homogeneous and, generally, its anatomical and spatial heterogeneity with respect to radiation response are not taken into consideration. However, advances in imaging and radiation techniques as well as an improved understanding of the radiobiological response of organs have raised the possibility of sparing the critical functional structures within various organs at risk during intensity-modulated radiotherapy. Here, we discuss these structures, which include the critical brain structure, or neural nuclei, and the nerve fiber tracts in the CNS, head and neck structures related to radiation-induced salivary and swallowing dysfunction, and functional structures in the heart and lung. We suggest that these structures can be used as potential surrogate organs at risk in order to minimize their radiation dose and/or irradiated volume without compromising the dose coverage of the target volume during radiation treatment.
Related JoVE Video
Visual outcomes of cataract surgery performed by supervised novice surgeons during training in rural China.
Clin. Experiment. Ophthalmol.
PUBLISHED: 08-09-2013
Show Abstract
Hide Abstract
To assess the outcomes of cataract surgery performed by novice surgeons during training in a rural programme. DESIGN?: Retrospective study.
Related JoVE Video
[Effect of the insulation layer of tissue-engineering scaffold on collagen type II expression in the neo-cartilage].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 07-11-2013
Show Abstract
Hide Abstract
To investigate the effect of the insulation layer in the tissue-engineering composite osteochondral scaffolds on collagen type II expression in the neo-cartilage.
Related JoVE Video
Complete mitochondrial genome of the blue-spotted stingray Neotrygon kuhlii (Myliobatiformes: Dasyatidae).
Mitochondrial DNA
PUBLISHED: 07-02-2013
Show Abstract
Hide Abstract
Abstract The blue-spotted stingray Neotrygon kuhlii is a small stingray distributed in the Indian and West Pacific Ocean. It was considered a species complex by morphological and molecular evidences. In this study, we firstly presented the complete mitochondrial genome of N. kuhlii. It is 18,039?bp in length, including 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and 1 control region, with the typical gene order in the mitogenomes of vertebrates. The total base composition is 31.9% A, 26.4% C, 13.1% G and 28.6% T, with an A?+?T bias of 60.5%. Alignment results demonstrated that the mitochondrial sequences of N. kuhlii in this study were highly similar to the 12S, 16S, COI and Cyt b sequences of the specimens collected from the Chinese seas in other studies.
Related JoVE Video
Complete mitochondrial genome of the tiger shark Galeocerdo cuvier (Carcharhiniformes: Carcharhinidae).
Mitochondrial DNA
PUBLISHED: 07-02-2013
Show Abstract
Hide Abstract
Abstract The tiger shark Galeocerdo cuvier is the only member of the genus Galeocerdo. The complete mitochondrial genome of G. cuvier is presented for the first time in this study. The gene composition and arrangement in the mitogenome of G. cuvier is identical to most animal mitogenome. There are 22?bp short noncoding sequences and 44 bp overlaps in the mitogenome. The overall base composition is 31.8% A, 23.9% C, 13.0% G and 31.3% T. The dihydrouridine arm of tRNA-Ser2 was replaced by a simple loop and the other tRNAs could be folded into the typical cloverleaf structure.
Related JoVE Video
Inhibition of notch signaling protects mouse lung against zymosan-induced injury.
Shock
PUBLISHED: 06-29-2013
Show Abstract
Hide Abstract
Notch signaling, a critical pathway in cell fate determination, is well known to be involved in immune and inflammatory reactions, whereas its role in acute lung injury (ALI) remains unclear. Here, we report that notch signal activity is upregulated in lung tissue harvested from an ALI mouse model (induced by zymosan). We showed that notch signal activity in lung tissue was increased 6 h after zymosan injection and peaked at 24 h. Inhibition of notch signaling by either pre- or post-zymosan treatment with N-[N-(3,5-difluorophenacetyl)-l-alanyl]-(S)-phenylglycine t-butyl ester (DAPT) significantly reduced lung injury, characterized by improvement in lung histopathology, lung permeability (protein concentration in bronchoalveolar lavage fluid and lung wet-to-dry weight ratio), lung inflammation (bronchoalveolar lavage fluid cell count, lung myeloperoxidase, and tumor necrosis factor ?), and also alleviated systemic inflammation and tissue damage, thus increasing the 7-day survival rate in zymosan-challenged mice. In conclusion, the role of notch signaling is functionally significant in the development of ALI. Inhibition of notch signaling by pretreatment or posttreatment with DAPT likely exerts its effects in part by mediating the expression of proinflammatory and anti-inflammatory cytokines and influencing tissue neutrophil recruitment. These results also imply that notch inhibitors may help attenuate local inflammatory lung damage.
Related JoVE Video
Specialized sorting of GLUT4 and its recruitment to the cell surface are independently regulated by distinct Rabs.
Mol. Biol. Cell
PUBLISHED: 06-26-2013
Show Abstract
Hide Abstract
Adipocyte glucose uptake in response to insulin is essential for physiological glucose homeostasis: stimulation of adipocytes with insulin results in insertion of the glucose transporter GLUT4 into the plasma membrane and subsequent glucose uptake. Here we establish that RAB10 and RAB14 are key regulators of GLUT4 trafficking that function at independent, sequential steps of GLUT4 translocation. RAB14 functions upstream of RAB10 in the sorting of GLUT4 to the specialized transport vesicles that ferry GLUT4 to the plasma membrane. RAB10 and its GTPase-activating protein (GAP) AS160 comprise the principal signaling module downstream of insulin receptor activation that regulates the accumulation of GLUT4 transport vesicles at the plasma membrane. Although both RAB10 and RAB14 are regulated by the GAP activity of AS160 in vitro, only RAB10 is under the control of AS160 in vivo. Insulin regulation of the pool of RAB10 required for GLUT4 translocation occurs through regulation of AS160, since activation of RAB10 by DENND4C, its GTP exchange factor, does not require insulin stimulation.
Related JoVE Video
Three-dimensional morphometric comparison of normal and apoptotic endothelial cells based on laser scanning confocal microscopy observation.
Microsc. Res. Tech.
PUBLISHED: 06-18-2013
Show Abstract
Hide Abstract
Three-dimensional (3D) morphometric analysis of cellular and subcellular structures provides an effective method for spatial cell biology. Here, 3D cellular and nuclear morphologies are reconstructed to quantify and compare morphometric differences between normal and apoptotic endothelial cells. Human umbilical vein endothelial cells (HUVECs) are treated with 60 ?M H2 O2 to get apoptotic cell model and then a series of sectional images are acquired from laser scanning confocal microscopy. The 3D cell model containing plasma membrane and cell nucleus is reconstructed and fused utilizing three sequential softwares or packages (Mimics, Geomagic, and VTK). The results reveal that H2 O2 can induce apoptosis effectively by regulating the activity of apoptosis-related biomolecules, including pro-apoptotic factors p53 and Bax, and anti-apoptotic factor Bcl-2. Compared with the normal HUVECs, the apoptotic cells exhibit significant 3D morphometric parameters (height, volume and nucleus-to-cytoplasm ratio) variation. The present research provides a new perspective on comparative quantitative analysis associated with cell apoptosis and points to the value of LSCM as an objective tool for 3D cell reconstruction.
Related JoVE Video
Ligand-free gadolinium oxide for in vivo T1-weighted magnetic resonance imaging.
Phys Chem Chem Phys
PUBLISHED: 06-17-2013
Show Abstract
Hide Abstract
Gadolinium oxide (Gd2O3), which can be used as a T1-weighted magnetic resonance imaging (MRI) contrast agent, has attracted intense attention in recent years. In this paper, ligand-free monoclinic Gd2O3 nanocrystals of 7.1 nm in diameter are synthesized by a simple and green approach, namely microsecond laser ablation of a gadolinium (Gd) target in deionized water. These nanocrystals obtain high r1 relaxivity of 5.53 s(-1) mM(-1), and their low toxicity was demonstrated by the cell viability of S18 cells and apoptosis in RAW264.7 cells. In vitro and in vivo MR images show these particles to be good T1-weighted MRI contrast agents. Base on the experimental results and theoretical analysis, we suggest that the purity of the Gd2O3 contributes to its high r1 relaxivity value, while the low toxicity is due to its good crystallinity. These findings show that laser ablation in liquid (LAL) is a promising strategy to synthesize ligand-free monoclinic Gd2O3 nanocrystals for use as high efficient T1-weighted MRI contrast agents.
Related JoVE Video
Novel Nanostructured Rare-Earth-Free Magnetic Materials with High Energy Products.
Adv. Mater. Weinheim
PUBLISHED: 06-13-2013
Show Abstract
Hide Abstract
Novel nanostructured Zr2 Co11 -based magnetic materials are fabricated in a single step process using cluster-deposition method. The composition, atomic ordering, and spin structure are precisely controlled to achieve a substantial magnetic remanence and coercivity, as well as the highest energy product for non-rare-earth and Pt-free permanent-magnet alloys.
Related JoVE Video
A novel fast responsive thermo-sensitive poly(N-isopropylacrylamide)-clay nanocomposites hydrogels modified by nanosized octavinyl polyhedral oligomeric silsesquioxane.
J Nanosci Nanotechnol
PUBLISHED: 06-13-2013
Show Abstract
Hide Abstract
The preparation of a novel fast response thremosensitive hydrogel was investigated by incorporating nanosized octavinyl polyhedral oligomeric silsesquioxane (OvPOSS) particles into inorganic clay-crosslinked poly(N-isopropylacrylamide) (PNIPA) nanocomposites hydrogels (NC gels). The resulting hydrogels named as P-NC gels involving both the strategies of NC gels and double network gels (DN gels) were successfully synthesized via a two-step technique. The second PNIPA network crosslinked by OvPOSS were polymerized in the presence of the first clay-PNIPA network. The P-NC gels were characterized by FTIR, X-ray, DSC, UV/vis,spectra, SEM, mechanical properties and swelling behaviors measurements. The key factor for preparing homogenous P-NC gels with good transparency was the low concentration of OvPOSS (c(OvPOSS)) dispersed uniformly in polymer as a cross-linker. On the contrary, the high c(OvPOSS) led to the significant aggregation of the OvPOSS particles and thus resulted in the heterogeneity of gels. The SEM images of freeze-dried P-NC gels exhibited a highly interconnected microporous network structure, which could be adjusted by varying the amount of OvPOSS. The special porous morphology brought about an attractive faster swelling/deswelling rate than that of normal NC gels. All properties of P-NC gels displayed an obvious dependence on the concentration of incorporated OvPOSS. The excellent mechanical properties, tunable LCST, especially the fast deswelling rate make these hydrogels potential candidates for applications in drug release and other biological fields.
Related JoVE Video
Correlation of EGFR mutation and predominant histologic subtype according to the new lung adenocarcinoma classification in Chinese patients.
Med. Oncol.
PUBLISHED: 05-14-2013
Show Abstract
Hide Abstract
A new lung adenocarcinoma classification proposed by the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society (IASLC/ATS/ERS) has recently been published. However, the relationship between EGFR mutations and subtype of adenocarcinoma remains unclear. A total of 161 surgically resected lung adenocarcinomas in Zhejiang Cancer Hospital were reviewed using the new classification system. Epidermal growth factor receptor (EGFR) mutations were observed in 67 cases (41.6 %). EGFR mutations were found to be closely associated with the micropapillary predominant subtype (P = 0.0068) and lepidic component (P = 0.005). The frequency of EGFR mutation was found to be lower in the solid predominant subtype than other subtype (P = 0.04). In conclusion, histologic subtyping was found to be associated with EGFR mutations. The EGFR mutation frequency of micropapillary and lepidic predominant subtypes was found to be more pronounced than that of other subtypes.
Related JoVE Video
Aggregation-Mediated Macromolecular Uptake by a Molecular Transporter.
ACS Chem. Biol.
PUBLISHED: 04-26-2013
Show Abstract
Hide Abstract
Endocytosis is a key process in cellular delivery of macromolecules by molecular transporters, although the mechanism of internalization remains unclear. Here, we probe the cellular uptake of streptavidin using biotinylated guanidinoneomycin (biotinGNeo), a low molecular weight guanidinium-rich molecular transporter. Two distinct modes were explored: (i) incubation of cells with a preformed tetravalent streptavidin-(biotinGNeo)4 conjugate and (ii) preincubation of cells with the biotinGNeo before exposure to streptavidin. A significant enhancement in uptake was observed after preincubation with biotinGNeo. FRET studies showed that the enhanced uptake was accompanied by extensive aggregation of streptavidin on the cell surface. Because guanidinylated neomycin was previously found to exclusively bind to heparan sulfate, our observations suggest that heparan sulfate proteoglycan aggregation is a pivotal step for endocytic entry into cells by guanidinoglycosides. These observations put forward a practical and general pathway for the cellular delivery of diverse macromolecules.
Related JoVE Video
Causes and five-year incidence of blindness and visual impairment in urban Southern China: the Liwan Eye Study.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 04-25-2013
Show Abstract
Hide Abstract
We determined the causes and five-year incidence of blindness and visual impairment (VI) in an adult, urban Chinese population.
Related JoVE Video
Analysis of Predictive Factors for Postoperative Survival for Non Small Cell Lung Carcinoma Patients with Unexpected Mediastinal Lymph Nodes Metastasis.
Thorac Cardiovasc Surg
PUBLISHED: 04-12-2013
Show Abstract
Hide Abstract
Objectives To discuss the predictive factors of postoperative survival for non small cell lung carcinoma (NSCLC) patients with clinical N0 stage but postoperative pathological N2 stage (cN0-pN2).Methods From January 1, 2005, to December 31, 2009, the clinical data of NSCLC patients with cN0-pN2 after radical surgery were retrospectively collected, and their survival information was collected through follow-up. The expiration date for follow-up was December 31, 2011. The predictive factors of postoperative survival for NSCLC patients with unexpected mediastinal lymph node metastasis were analyzed using Cox proportional hazards regression.Results A total of 263 patients were enrolled. The follow-up rate was 91.63%. The overall 1-, 3-, and 5-year survival rates were 94.6, 55.2, and 26.3%, respectively. Video-assisted thoracotomy surgery (VATS; odds ratio [OR] 0.659; 95% confidence interval [CI] 0.469 to 0.927; p = 0.017), multiple stations of metastatic mediastinal lymph nodes (OR 1.605; 95% CI 1.180 to 2.183; p = 0.003), and no adjuvant chemotherapy (OR 1.576; 95% CI 1.105 to 2.246; p = 0.012) were independent predictive factors for unexpected N2 patients. The median survival after VATS was superior to that after thoracotomy for patients with a single station of metastatic mediastinal lymph node (48.45 m vs 37.34 m, p = 0.018). The median survival without any adjuvant chemotherapy was inferior to that after adjuvant chemotherapy for patients with multiple stations of metastatic mediastinal lymph nodes (20.32 m vs 31.55 m, p = 0.001).Conclusion The postoperative survival for NSCLC patients with cN0-pN2 was related to operational method, adjuvant chemotherapy, and the number of metastatic mediastinal lymph node stations. Patients with a single station of metastatic mediastinal lymph node are likely to benefit from VATS, whereas patients with multiple stations of metastatic mediastinal lymph nodes are likely to benefit from adjuvant chemotherapy.
Related JoVE Video
Roles of SIRT1 in leukemogenesis.
Curr. Opin. Hematol.
PUBLISHED: 03-23-2013
Show Abstract
Hide Abstract
This review provides a concise summary of significant research progress on SIRT1 deacetylase in leukemia in the past year. SIRT1 is a multifunctional protein and recent studies demonstrate that SIRT1 plays a crucial role in myeloid leukemogenesis and drug resistance.
Related JoVE Video
Phenotypic and genetic correlation of blood pressure and body mass index with retinal vascular caliber in children and adolescents: the Guangzhou twin eye study.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 03-21-2013
Show Abstract
Hide Abstract
To examine the phenotypic and genetic associations of blood pressure and body mass index (BMI) with retinal vascular caliber.
Related JoVE Video
Novel cigarlike TiO2 nanofibers: fabrication, improved mechanical, and electrochemical performances.
ACS Appl Mater Interfaces
PUBLISHED: 03-15-2013
Show Abstract
Hide Abstract
By coupling the self-assembly of polystyrene-block-poly(ethylene oxide) (PS-b-PEO) containing titanium precursors with the electrospinning technique, novel cigarlike nanofibers with an outer-shell and inner-continuous-pore structure and resultant fabrics were fabricated. Different from typical porous metal oxides, the prepared high-surface-area nonwoven fabrics show excellent mechanical properties. Not only are these fabrics self-supporting over a large area, but they can also be cut using scissors, which is important for large-scale applications. Furthermore, as electrode materials in Li-ion batteries, these fabrics exhibit much higher charge/discharge capacity and cycle stability compared with the commercially available nanosized TiO2 (P25). The improved mechanical and electrochemical performances are attributed to the presence of an outer-shell, inner-bicontinuous structures (including continuous TiO2 frame and continuous nanopores) and hierarchical pores from the cigarlike nanofibers.
Related JoVE Video
Feasibility and long-term efficacy of video-assisted thoracic surgery for unexpected pathologic N2 disease in non-small cell lung cancer.
Ann Thorac Med
PUBLISHED: 03-04-2013
Show Abstract
Hide Abstract
This study compares early and late outcomes for treatment by video-assisted thoracic surgery (VATS) versus treatment by thoracotomy for clinical N0, but post-operatively unexpected, pathologic N2 disease (cN0-pN2).
Related JoVE Video
Perceived difficulty of various steps of manual small incision cataract surgery among trainees in rural China.
Clin. Experiment. Ophthalmol.
PUBLISHED: 03-03-2013
Show Abstract
Hide Abstract
The perceived difficulty of steps of manual small incision cataract surgery among trainees in rural China was assessed.
Related JoVE Video
Promotion of neuronal differentiation of neural progenitor cells by using EGFR antibody functionalized collagen scaffolds for spinal cord injury repair.
Biomaterials
PUBLISHED: 02-26-2013
Show Abstract
Hide Abstract
The main challenge for neural progenitor cell (NPC)-mediated repair of spinal cord injury (SCI) is lack of favorable environment to direct its differentiation towards neurons rather than glial cells. The myelin associated inhibitors have been demonstrated to promote NPC differentiation into glial lineage. Herein, to inhibit the downstream signaling activated by myelin associated inhibitors, cetuximab, an epidermal growth factor receptor (EGFR) neutralizing antibody, functionalized collagen scaffold has been developed as a vehicle for NPC implantation. It was found that collagen-cetuximab 1 ?g scaffolds enhanced neuronal differentiation and inhibited astrocytic differentiation of NPCs exposed to myelin proteins significantly in vitro. To test the therapeutic effect in vivo, NPCs expressing green fluorescent protein (GFP)-embedded scaffolds have been implanted into the 4 mm-long hemisection lesion of rats. We found that the collagen-cetuximab 5 ?g scaffolds induced neuronal differentiation and decreased astrocytic differentiation of NPCs, enhanced axon regeneration, and promoted functional recovery markedly. A well-functionalized scaffold was constructed to improve the recovery of SCI, which could promote the neuronal differentiation of neural progenitor cells in vivo.
Related JoVE Video
A correlational study of scoliosis and trunk balance in adult patients with mandibular deviation.
PLoS ONE
PUBLISHED: 02-20-2013
Show Abstract
Hide Abstract
Previous studies have confirmed that patients with mandibular deviation often have abnormal morphology of their cervical vertebrae. However, the relationship between mandibular deviation, scoliosis, and trunk balance has not been studied. Currently, mandibular deviation is usually treated as a single pathology, which leads to poor clinical efficiency. We investigated the relationship of spine coronal morphology and trunk balance in adult patients with mandibular deviation, and compared the finding to those in healthy volunteers. 35 adult patients with skeletal mandibular deviation and 10 healthy volunteers underwent anterior X-ray films of the head and posteroanterior X-ray films of the spine. Landmarks and lines were drawn and measured on these films. The axis distance method was used to measure the degree of scoliosis and the balance angle method was used to measure trunk balance. The relationship of mandibular deviation, spine coronal morphology and trunk balance was evaluated with the Pearson correlation method. The spine coronal morphology of patients with mandibular deviation demonstrated an "S" type curve, while a straight line parallel with the gravity line was found in the control group (significant difference, p<0.01). The trunk balance of patients with mandibular deviation was disturbed (imbalance angle >1°), while the control group had a normal trunk balance (imbalance angle <1°). There was a significant difference between the two groups (p<0.01). The degree of scoliosis and shoulder imbalance correlated with the degree of mandibular deviation, and presented a linear trend. The direction of mandibular deviation was the same as that of the lateral bending of thoracolumbar vertebrae, which was opposite to the direction of lateral bending of cervical vertebrae. Our study shows the degree of mandibular deviation has a high correlation with the degree of scoliosis and trunk imbalance, all the three deformities should be clinically evaluated in the management of mandibular deviation.
Related JoVE Video
Control of diastereoselectivity for iridium-catalyzed allylation of a prochiral nucleophile with a phosphate counterion.
J. Am. Chem. Soc.
PUBLISHED: 01-30-2013
Show Abstract
Hide Abstract
We report a highly diastereo- and enantioselective allylation of azlactones catalyzed by the combination of a metallacyclic iridium complex and an optically inactive phosphate anion. The process demonstrates an approach for conducting diastereoselective reactions with prochiral nucleophiles in the presence of metallacyclic allyliridium complexes. The reaction provides access to an array of enantioenriched allylated azlactones containing adjacent tertiary and quaternary carbon centers. Preliminary mechanistic studies suggest that the phosphate and methyl carbonate anions together induce the unusually high diastereoselectivity.
Related JoVE Video
Sensitive detection of BRAF V600E mutation by Amplification Refractory Mutation System (ARMS)-PCR.
Biomark Res
PUBLISHED: 01-16-2013
Show Abstract
Hide Abstract
BRAF mutations occur in approximately 8% of all human cancers and approach 50% in melanoma and papillary carcinoma of thyroid. These mutations provide potentially valuable diagnostic, prognostic and treatment response prediction markers. A sensitive, specific, low-cost assay to detect these mutations is needed.
Related JoVE Video
III-V nanocrystals capped with molecular metal chalcogenide ligands: high electron mobility and ambipolar photoresponse.
J. Am. Chem. Soc.
PUBLISHED: 01-16-2013
Show Abstract
Hide Abstract
In this work, we synthesized InP and InAs nanocrystals (NCs) capped with different inorganic ligands, including various molecular metal chalcogenide complexes (MCCs) and chalcogenide ions. We found that MCCs and chalcogenide ions can quantitatively displace organic ligands from the surface of III-V NCs and serve as the inorganic capping groups for III-V NC surfaces. These inorganic ligands stabilize colloidal solutions of InP and InAs NCs in polar solvents and greatly facilitate charge transport between individual NCs. Charge transport studies revealed high electron mobility in the films of MCC-capped InP and InAs NCs. For example, we found that bridging InAs NCs with Cu(7)S(4)(-) MCC ligands can lead to very high electron mobility exceeding 15 cm(2)/(V s). In addition, we observed unprecedented ambipolar (positive/negative) photoresponse of MCC-capped InAs NC solids that changed sign depending on the ligand chemistry, illumination wavelength, and doping of the NC solid. For example, the sign of photoconductance of InAs NCs capped with Cu(7)S(4)(-) or Sn(2)S(6)(4-) ions converted from positive at 0.80 and 0.95 eV to negative at 1.27 and 1.91 eV. We propose an explanation of this unusually complex photoconductivity of InAs NC solids.
Related JoVE Video
MiR-138 inhibits tumor growth through repression of EZH2 in non-small cell lung cancer.
Cell. Physiol. Biochem.
PUBLISHED: 01-15-2013
Show Abstract
Hide Abstract
MicroRNAs (miRNAs) play important roles in tumorigenesis. We investigated the roles and mechanisms of miR-138 in human non-small cell lung cancer (NSCLC).
Related JoVE Video
Immunoproteomic to identify antigens in the intestinal mucosa of Crohns disease patients.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Incidences of Crohn disease (CD) have increased significantly in the last decade. Immunoproteomics are a promising method to identify biomarkers of different diseases. In the present study, we used immunoproteomics to study proteins of intestinal mucosal lesions and neighboring normal intestinal mucosa of 8 CD patients. Reactive proteins were validated by Western blotting. Approximately 50 protein spots localized in the 4 to 7 pI range were detected on two-dimensional electrophoresis gels, and 6 differentially expressed protein spots between 10 and 100 kDa were identified. Reactive proteins were identified as prohibitin, calreticulin, apolipoprotein A-I, intelectin-1, protein disulfide isomerase, and glutathione s-transferase Pi. Western blotting was conducted on the intestinal mucosa of another 4 CD patients to validate the reactive proteins. We found that intestinal mucosal lesions had high levels of prohibitin expression. Glutathione s-transferase expression was detected in 100% of the intestinal mucosa examined. Thus, we report 6 autoantigens of CD, including 3 new and 3 previously reported autoantigens. Intelectin-1, protein disulfide isomerase, and glutathione-s-transferases may be used as biomarkers for CD pathogenesis.
Related JoVE Video
Efficacy and Tolerability of the Fixed Combinations Latanoprost/Timolol versus Dorzolamide/Timolol in Patients with Elevated Intraocular Pressure: A Meta-Analysis of Randomized Controlled Trials.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
To evaluate the efficacy and tolerability of the fixed combination of Latanoprost/Timolol versus Dorzolamide/Timolol in the treatment of patients with elevated intraocular pressure (IOP).
Related JoVE Video
Target volume and position variations during intensity-modulated radiotherapy for patients with nasopharyngeal carcinoma.
Onco Targets Ther
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Considerable anatomical changes occur during intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC). This study aimed to quantify volumetric and positional variations of the target volume during IMRT.
Related JoVE Video
HER2 status in gastric and gastroesophageal junction cancer assessed by local and central laboratories: Chinese results of the HER-EAGLE study.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Trastuzumab has been approved for human epidermal growth factor receptor 2 (HER2)-positive advanced gastric and gastroesophageal junction cancers (GC and GJC) in combination with chemotherapy. The aim of this HER2 early/advanced gastric epidemiology (HER-EAGLE) study was to evaluate the frequency of HER2 over-expression and to evaluate agreement on HER2 status assessment in GC and GJC patients in local laboratories versus a central laboratory in China. Tumor samples from 734 GC or GJC patients who were enrolled at 11 different hospitals in China were examined. HER2 status was assessed by immunohistochemistry (IHC), and followed by dual-color silver-enhanced in Situ hybridization (DSISH) in IHC 2+ cases. Clinicopathologic characteristics were collected from all of the patients. HER2-positive tumors were identified in 12.0% (88/734) of the GC and GJC cases. There were significantly higher rates of HER2 positivity in patients with GJC (GJC: 18.1%, GC: 9.7%, P=0.002), and intestinal-type cancers using the Lauren classification (intestinal: 23.6%, diffuse/mixed: 4.3%, P<0.0001). No significant difference in HER2 positivity was identified between resection and biopsy samples, or between early and advanced disease stages. The agreement between local laboratories and the central laboratory on HER2 status scoring was good (kappa=0.86). The main reason of HER2 status discordance between local and the central laboratories was IHC result mis-interpretation in local laboratories. These results suggest that IHC followed by DSISH testing is an accurate and cost-effective procedure in China.
Related JoVE Video
Nanosilica coating for bonding improvements to zirconia.
Int J Nanomedicine
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Resin bonding to zirconia cannot be established from standard methods that are currently utilized in conventional silica-based dental ceramics. The solution-gelatin (sol-gel) process is a well developed silica-coating technique used to modify the surface of nonsilica-based ceramics. Here, we use this technique to improve resin bonding to zirconia, which we compared to zirconia surfaces treated with alumina sandblasting and tribochemical silica coating. We used the shear bond strength test to examine the effect of the various coatings on the short-term resin bonding of zirconia. Furthermore, we employed field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, atomic force microscopy, and Fourier transform infrared spectroscopy to characterize the zirconia surfaces. Water-mist spraying was used to evaluate the durability of the coatings. To evaluate the biological safety of the experimental sol-gel silica coating, we conducted an in vitro Salmonella typhimurium reverse mutation assay (Ames mutagenicity test), cytotoxicity tests, and in vivo oral mucous membrane irritation tests. When compared to the conventional tribochemical silica coating, the experimental sol-gel silica coating provided the same shear bond strength, higher silicon contents, and better durability. Moreover, we observed no apparent mutagenicity, cytotoxicity, or irritation in this study. Therefore, the sol-gel technique represents a promising method for producing silica coatings on zirconia.
Related JoVE Video
Estimation of the displacement of cardiac substructures and the motion of the coronary arteries using electrocardiographic gating.
Onco Targets Ther
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
The aim of this study was to quantify the displacement of cardiac substructures, including the anterior myocardial territory (AMT), left ventricle, and coronary arteries during a normal cardiac cycle.
Related JoVE Video
Activation of stress response gene SIRT1 by BCR-ABL promotes leukemogenesis.
Blood
PUBLISHED: 12-29-2011
Show Abstract
Hide Abstract
The tyrosine kinase inhibitor imatinib is highly effective in the treatment of chronic myelogenous leukemia (CML), but primary and acquired resistance of CML cells to the drug offset its efficacy. Molecular mechanisms for resistance of CML to tyrosine kinase inhibitors are not fully understood. In the present study, we show that BCR-ABL activates the expression of the mammalian stress response gene SIRT1 in hematopoietic progenitor cells and that this involves STAT5 signaling. SIRT1 activation promotes CML cell survival and proliferation associated with deacetylation of multiple SIRT1 substrates, including FOXO1, p53, and Ku70. Imatinib-mediated inhibition of BCR-ABL kinase activity partially reduces SIRT1 expression and SIRT1 inhibition further sensitizes CML cells to imatinib-induced apoptosis. Knockout of SIRT1 suppresses BCR-ABL transformation of mouse BM cells and the development of a CML-like myeloproliferative disease, and treatment of mice with the SIRT1 inhibitor tenovin-6 deters disease progression. The combination of SIRT1 gene knockout and imatinib treatment further extends the survival of CML mice. Our results suggest that SIRT1 is a novel survival pathway activated by BCR-ABL expression in hematopoietic progenitor cells, which promotes oncogenic transformation and leukemogenesis. Our findings suggest further exploration of SIRT1 as a therapeutic target for CML treatment to overcome resistance.
Related JoVE Video
Neuronal regeneration and protection by collagen-binding BDNF in the rat middle cerebral artery occlusion model.
Biomaterials
PUBLISHED: 08-21-2011
Show Abstract
Hide Abstract
It has been well confirmed that brain-derived neurotrophic factor (BDNF) has therapeutic effects following stroke. However, it is difficult to be maintained at a sufficient concentration of BDNF in the infarcted hemisphere. We have shown in our previous work that BDNF fused with a collagen-binding domain (CBD-BDNF) could specifically bind to collagen. The ventricular ependyma of the brain is rich in collagen. Therefore, we have speculated that in the infarcted hemisphere, CBD-BDNF will bind to the collagen of the ventricular ependyma and stimulate the cell proliferation in the subventricular zone (SVZ). Using a rat middle cerebral artery occlusion model (MCAO), we injected CBD-BDNF into the lateral ventricle of MCAO rats. The results demonstrated that CBD-BDNF was retained at high levels in the infarcted hemisphere, promoted neural regeneration and angiogenesis, reduced cell loss, decreased apoptosis, and improved functional recovery. In addition, brain perfusion and metabolism, as evaluated by SPECT and PET, were improved in the CBD-BDNF treated group.
Related JoVE Video
Deletion of Tet2 in mice leads to dysregulated hematopoietic stem cells and subsequent development of myeloid malignancies.
Blood
PUBLISHED: 07-29-2011
Show Abstract
Hide Abstract
TET2 is mutated/deleted with high frequencies in multiple forms of myeloid malignancies including MDS, CMML, MPN, and AML. However, little is known regarding the biological function of TET2 and its role in the pathogenesis of myeloid malignancies. To study the function of TET2 in vivo, we generated a Tet2 knock out mouse model. Deletion of Tet2 in mice led to dramatic reduction in the 5-hydroxymethylcytosine levels and concomitant increase in the 5-methylcytosine levels in the genomic DNA of BM cells. The Tet2(-/-) mice contained an increased Lin(-)Sca-1(+)c-Kit(+) (LSK) cell pool before the development of myeloid malignancies. A competitive reconstitution assay revealed that Tet2(-/-) LSK cells had an increased hematopoietic repopulating capacity with an altered cell differentiation skewing toward monocytic/granulocytic lineages. Approximately 1/3 of Tet2(-/-) and 8% of Tet2(+/-) mice died within 1 year of age because of the development of myeloid malignancies resembling characteristics of CMML, MPD-like myeloid leukemia, and MDS. Furthermore, transplantation of Tet2(-/-), but not wild-type (WT) or Tet2(+/-) BM cells, led to increased WBC counts, monocytosis, and splenomegaly in WT recipient mice. These data indicate that Tet2-deficient mice recapitulate patients with myeloid malignancies, implying that Tet2 functions as a tumor suppressor to maintain hematopoietic cell homeostasis.
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.