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Find video protocols related to scientific articles indexed in Pubmed.
Single Drop Solution Electrode Glow Discharge for Plasma Assisted-Chemical Vapor Generation: Sensitive Detection of Zinc and Cadmium in Limited Amounts of Samples.
Anal. Chem.
PUBLISHED: 11-20-2014
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A simple and sensitive approach is proposed and evaluated for determination of ultratrace Zn and Cd in limited amounts of samples or tens of cells based on a novel single drop (5-20 ?L) solution electrode glow discharge assisted-chemical vapor generation technique. Volatile species of Zn and Cd were immediately generated and separated from the liquid phase for transporting to atomic fluorescence or atomic mass spectrometric detectors for their determination only using hydrogen when the glow discharge was ignited between the surface of a liquid drop and the tip of a tungsten electrode. Limits of detection are better than 0.01 µg L-1 (0.2 pg) for Cd and 0.1 µg L-1 (2 pg) for Zn, respectively, and comparable or better than the previously reported results due to only a 20 µL sampling volume required, which makes the proposed technique convenient for the determination of Zn and Cd in limited amounts of samples or even only tens of cells. The proposed method not only retains the advantages of conventional chemical vapor generation but also provides several unique advantages, including better sensitivity, lower sample and power consumption, higher chemical vapor generation efficiencies and simpler setup as well as greener analytical chemistry. The utility of this technique was demonstrated by the determination of ultra-trace Cd and Zn in several single human hair samples, Certified Reference Materials GBW07601a (human hair powder) and paramecium cells.
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Simian Hemorrhagic Fever Virus Cell Entry is Dependent on CD163 and Uses a Clathrin-mediated Endocytosis-like Pathway.
J. Virol.
PUBLISHED: 10-31-2014
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Simian hemorrhagic fever virus (SHFV) causes a severe and almost uniformly fatal viral hemorrhagic fever in Asian macaques, but is thought to be nonpathogenic for humans. To date, the SHFV lifecycle is almost completely uncharacterized on the molecular level. Here we describe the first steps of the SHFV lifecycle. Our experiments indicate that SHFV enters target cells by low pH-dependent endocytosis. Dynamin inhibitors, chlorpromazine, methyl-?-cyclodextrin, chloroquine, and concanamycin A dramatically reduced SHFV entry efficiency, whereas the macropinocytosis inhibitors EIPA, blebbistatin, and wortmannin, and the caveolin-mediated endocytosis inhibitors nystatin and filipin III had no effect. Furthermore, overexpression and knock-out study and electron-microscopy results indicate that SHFV entry occurs by a dynamin-dependent clathrin-mediated endocytosis-like pathway. Experiments utilizing latrunculin B, cytochalasin B, and cytochalasin D indicate that SHFV does not hijack the actin polymerization pathway. Treatment of target cells with proteases (proteinase K, papain, ?-chymotrypsin, trypsin) abrogated entry, indicating that the SHFV cell-surface receptor is a protein. Phospholipases A2 and D had no effect on SHFV entry. Finally, treatment of cells with antibodies targeting CD163, a cell surface molecule identified as an entry factor for the SHFV-related porcine reproductive and respiratory syndrome virus, diminished SHFV replication, identifying CD163 as an important SHFV entry component.
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A Genetically Encoded Alkyne Directs Palladium-Mediated Protein Labeling on Live Mammalian Cell Surface.
ACS Chem. Biol.
PUBLISHED: 10-28-2014
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The merging of site-specific incorporation of small bioorthogonal functional groups into proteins via amber codon suppression with bioorthogonal chemistry has created exciting opportunities to extend the power of organic reactions to living systems. Here we show that a new alkyne amino acid can be site-selectively incorporated into mammalian proteins via a known orthogonal pyrrolysyl-tRNA synthetase/tRNACUA pair and directs an unprecedented, palladium-mediated cross-coupling reaction-driven protein labeling on live mammalian cell surface. A comparison study with the alkyne-encoded proteins in vitro indicated that this terminal alkyne is better suited for the palladium-mediated cross-coupling reaction than the copper-catalyzed click chemistry.
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The synthesis of multi-structured SnS nanocrystals toward enhanced performance for photovoltaic devices.
Nanoscale
PUBLISHED: 10-24-2014
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The synthesis of multi-scale SnS nanostructures with favorable fluorescence is facilely accomplished via a well-excogitated gentle process, involving simple precursors, stabilized chemical medium and primitive ligand exchange. The fabricated SnS nanocrystals can be adopted as hole transporting materials in photovoltaic devices for enhancing its power conversion efficiency.
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[Effect of dangua recipe on glycolipid metabolism and VCAM-1 and its mRNA expression level in Apo E(-/-) mice with diabetes mellitus].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 10-23-2014
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To study the effect of Dangua Recipe (DGR) on glycolipid metabolism, vascular cell adhesion molecule-1 (VCAM-1) and its mRNA expression level of transgenic Apo E(-/-) mouse with spontaneous atherosclerosis, thus revealing its partial mechanism for curing diabetes mellitus (DM) with angiopathy.
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Melatonin enhances plant growth and abiotic stress tolerance in soybean plants.
J. Exp. Bot.
PUBLISHED: 10-10-2014
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Melatonin is a well-known agent that plays multiple roles in animals. Its possible function in plants is less clear. In the present study, we tested the effect of melatonin (N-acetyl-5-methoxytryptamine) on soybean growth and development. Coating seeds with melatonin significantly promoted soybean growth as judged from leaf size and plant height. This enhancement was also observed in soybean production and their fatty acid content. Melatonin increased pod number and seed number, but not 100-seed weight. Melatonin also improved soybean tolerance to salt and drought stresses. Transcriptome analysis revealed that salt stress inhibited expressions of genes related to binding, oxidoreductase activity/process, and secondary metabolic processes. Melatonin up-regulated expressions of the genes inhibited by salt stress, and hence alleviated the inhibitory effects of salt stress on gene expressions. Further detailed analysis of the affected pathways documents that melatonin probably achieved its promotional roles in soybean through enhancement of genes involved in cell division, photosynthesis, carbohydrate metabolism, fatty acid biosynthesis, and ascorbate metabolism. Our results demonstrate that melatonin has significant potential for improvement of soybean growth and seed production. Further study should uncover more about the molecular mechanisms of melatonin's function in soybeans and other crops.
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Single-Junction Polymer Solar Cells Exceeding 10% Power Conversion Efficiency.
Adv. Mater. Weinheim
PUBLISHED: 10-01-2014
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A single-junction polymer solar cell with an efficiency of 10.1% is demonstrated by using deterministic aperiodic nanostructures for broadband light harvesting with optimum charge extraction. The performance enhancement is ascribed to the self-enhanced absorption due to collective effects, including the pattern-induced anti-reflection, light scattering as well as surface plasmonic resonance, together with a minimized recombination probability.
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Synthesis of cell-permeable stapled BH3 peptide-based Mcl-1 inhibitors containing simple aryl and vinylaryl cross-linkers.
Tetrahedron
PUBLISHED: 10-01-2014
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We report the synthesis of a series of distance-matching aryl and vinylaryl cross-linkers for constructing stapled peptides containing cysteines at i,i+7 positions. Langevin dynamics simulation studies helped to classify these cross-linkers into two categories: the rigid cross-linkers with narrower S-S distance distribution and the flexible cross-linkers with wider S-S distance distribution. The stapled Noxa BH3 peptides with the flexible distance-matching cross-linkers gave the highest degree of helicity as well as the most potent inhibitory activity against Mcl-1. However, the stapled peptides with the highest hydrophobicity showed the most efficient cellular uptake. Together, this work illustrates the divergent nature of binding affinity and cellular uptake, and the vital importance of choosing appropriate cross-linkers in constructing stapled peptides with the drug-like properties.
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Overexpression of Human ABCB1 in Cancer Cells Leads to Reduced Activity of GSK461364, a Specific Inhibitor of Polo-like Kinase 1.
Mol. Pharm.
PUBLISHED: 09-18-2014
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Polo-like kinase 1 (Plk1) is a serine/threonine kinase involved in the regulation of mitosis and is overexpressed in many tumor types. Inhibition of Plk1 leads to cell cycle arrest, onset of apoptosis, and cell death, thus Plk1 has emerged as an important target for cancer treatment. GSK461364 is a potent inhibitor of Plk1 that inhibits the proliferation of multiple human cancer cell lines by promoting G2/M cell cycle arrest at low concentrations. However, as is the case for many therapeutic drugs, the risk of developing drug resistance to GSK461364 can present a therapeutic challenge to clinicians. Since the overexpression of ATP-binding cassette (ABC) drug transporter ABCB1 is one of the most common mechanisms of drug resistance, we aimed to investigate the effect of ABCB1 on the cellular efficacy of GSK461364. In this study, we observed a significantly reduced activity of GSK461364 in cells overexpressing human ABCB1. We showed that GSK461364 stimulates the ABCB1 ATPase activity and competitively inhibits ABCB1-mediated efflux of calcein-AM in a concentration-dependent manner. Moreover, as a way to assess the impact of ABCB1 on the efficacy of GSK461364, we evaluated the G2/M cell cycle arrest and apoptosis induced by GSK461364. We discovered that, by inhibiting the function of ABCB1, the reduced G2/M cell cycle arrest, apoptosis, and sensitivity to GSK461364 treatment in ABCB1-overexpressing cells can be significantly restored. In conclusion, in order to achieve a better therapeutic outcome, combination therapy of GSK461364 with a modulator of ABCB1 should be further investigated as a potential treatment approach.
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Initial study of biexponential model of intravoxel incoherent motion magnetic resonance imaging in evaluation of the liver fibrosis.
Chin. Med. J.
PUBLISHED: 09-06-2014
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The diagnosis of liver fibrosis is a difficult task at any time using conventional clinical imaging. Intravoxel incoherent motion (IVIM) can be used to investigate both diffusion and perfusion changes in tissues. This study was designed to determine the value of IVIM in the diagnosis and staging of liver fibrosis.
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[Diagnostic role of contrast-enhanced whole-heart coronary magnetic resonance angiography in the evaluation of coronary artery disease].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-26-2014
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To prospectively evaluate the diagnostic effectiveness of contrast-enhanced whole-heart coronary magnetic resonance angiography (CE-CMRA) in patients with suspected coronary artery disease (CAD) with conventional coronary angiography as the reference standard.
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HATCN-based charge recombination layers as effective interconnectors for tandem organic solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 08-25-2014
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A comprehensive understanding of the energy-level alignment at the organic heterojunction interfaces is of paramount importance to optimize the performance of organic solar cells (OSCs). Here, the detailed electronic structures of organic interconnectors, consisting of cesium fluoride-doped 4,7-diphenyl-1,10-phenanthroline and hexaazatriphenylene-hexacarbonitrile (HATCN), have been investigated via in situ photoemission spectroscopy, and their impact on the charge recombination process in tandem OSCs has been identified. The experimental determination shows that the HATCN interlayer plays a significant role in the interface energetics with a dramatic decrease in the reverse built-in potential for electrons and holes from stacked subcells, which is beneficial to the charge recombination between HATCN and the adjacent layer. In accordance with the energy-level alignments, the open-circuit voltage of tandem OSC incorporating a HATCN-based interconnector is almost 2 times that of a single-cell OSC, revealing the effectiveness of the HATCN-based interconnectors in tandem organic devices.
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Storable N-phenylcarbamate palladacycles for rapid functionalization of an alkyne-encoded protein.
Chem. Commun. (Camb.)
PUBLISHED: 08-21-2014
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Here we report the synthesis of storable N-phenylcarbamate palladacycles that showed robust reactivity in the cross-coupling reaction with an alkyne-encoded protein with a second-order rate constant approaching 19?770 ± 930 M(-1) s(-1).
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Influenza A Virus Polymerase Is a Site for Adaptive Changes during Experimental Evolution in Bat Cells.
J. Virol.
PUBLISHED: 08-20-2014
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The recent identification of highly divergent influenza A viruses in bats revealed a new, geographically dispersed viral reservoir. To investigate the molecular mechanisms of host-restricted viral tropism and the potential for transmission of viruses between humans and bats, we exposed a panel of cell lines from bats of diverse species to a prototypical human-origin influenza A virus. All of the tested bat cell lines were susceptible to influenza A virus infection. Experimental evolution of human and avian-like viruses in bat cells resulted in efficient replication and created highly cytopathic variants. Deep sequencing of adapted human influenza A virus revealed a mutation in the PA polymerase subunit not previously described, M285K. Recombinant virus with the PA M285K mutation completely phenocopied the adapted virus. Adaptation of an avian virus-like virus resulted in the canonical PB2 E627K mutation that is required for efficient replication in other mammals. None of the adaptive mutations occurred in the gene for viral hemagglutinin, a gene that frequently acquires changes to recognize host-specific variations in sialic acid receptors. We showed that human influenza A virus uses canonical sialic acid receptors to infect bat cells, even though bat influenza A viruses do not appear to use these receptors for virus entry. Our results demonstrate that bats are unique hosts that select for both a novel mutation and a well-known adaptive mutation in the viral polymerase to support replication.
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Synergic effect between 5?fluorouracil and celecoxib on hypoxic gastric cancer cells.
Mol Med Rep
PUBLISHED: 08-14-2014
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5?fluorouracil (5?FU) is commonly used in the treatment of gastric cancer; however, resistance to this drug occurs under hypoxic conditions. Celecoxib may be used to reverse this resistance. The aim of the present study was to elucidate the inhibitory effects and mechanisms of 5?FU and celecoxib on the gastric cancer cell line SGC7901 under hypoxic conditions. SGC7901 cells were divided into four groups: Hypoxic control group, 5?FU group, celecoxib group and 5?FU/celecoxib combination group. Following treatment, the inhibition rates of cells were determined using an MTT assay. Protein and messenger RNA (mRNA) expression of hypoxia?inducible factor 2? (HIF?2?), adenosine triphosphate?binding cassette sub?family G member 2 (ABCG2) and octamer binding protein 4 (Oct?4) were determined using immunohistochemistry, reverse transcription quantitative polymerase chain reaction (RT?qPCR) and western blot analysis. The results demonstrated that the 5?FU/celecoxib combination group had a significantly higher inhibition rate than the individually treated 5?FU and celecoxib groups (P<0.05); inhibition rates were 66.09, 52.61 and 46.1%, respectively. mRNA and protein expression levels of HIF?2?, ABCG2 and Oct?4 were significantly lower in the celecoxib and 5?FU/celecoxib combination groups (P<0.01) compared with those of the hypoxia control and 5?FU groups. The 5?FU group demonstrated the highest levels of the respective mRNA and proteins. In conclusion, the results of the present study indicated that celecoxib had anti?tumor effects, as it was shown to inhibit tumor cell growth via the inhibition of HIF?2?, ABCG2 and Oct?4. The 5?FU/celecoxib combination had a synergic effect on tumor growth inhibition. This therefore suggested that inhibition of HIF?2?, ABCG2 and Oct?4 may be a potential method of reducing chemotherapy resistance and enhancing the effectiveness of chemotherapy treatment.
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Dan-gua Fang () improves glycolipid metabolic disorders by promoting hepatic adenosine 5'-monophosphate activated protein kinase expression in diabetic Goto-Kakizaki rats.
Chin J Integr Med
PUBLISHED: 08-07-2014
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To investigate the effect of Dan-gua Fang () on adenosine 5'-monophosphate (AMP) activated protein kinase (AMPK) ? expression in liver and subsequent improvement of glucose and lipid metabolism.
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A context-aware-based audio guidance system for blind people using a multimodal profile model.
Sensors (Basel)
PUBLISHED: 08-04-2014
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A wearable guidance system is designed to provide context-dependent guidance messages to blind people while they traverse local pathways. The system is composed of three parts: moving scene analysis, walking context estimation and audio message delivery. The combination of a downward-pointing laser scanner and a camera is used to solve the challenging problem of moving scene analysis. By integrating laser data profiles and image edge profiles, a multimodal profile model is constructed to estimate jointly the ground plane, object locations and object types, by using a Bayesian network. The outputs of the moving scene analysis are further employed to estimate the walking context, which is defined as a fuzzy safety level that is inferred through a fuzzy logic model. Depending on the estimated walking context, the audio messages that best suit the current context are delivered to the user in a flexible manner. The proposed system is tested under various local pathway scenes, and the results confirm its efficiency in assisting blind people to attain autonomous mobility.
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A germline mutation in the miR?125a coding region reduces miR?125a expression and is associated with human gastric cancer.
Mol Med Rep
PUBLISHED: 08-04-2014
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MicroRNAs (miRNAs) are small non-coding RNAs that inhibit the expression of target protein-coding genes, most often at the post-transcriptional level. miRNAs are often found to be misregulated in human cancer and they can act as potent oncogenes or tumor suppressor genes. In this study, we found that a germline mutation in the miR-125a coding region is associated with human gastric cancer. This mutation reduced the expression of mature miR-125a and alleviated its inhibitory effect on erythroblastic leukemia viral oncogene homolog 2 (ERBB2) gene expression and on gastric tumor cell proliferation. Thus, the data of this study suggested that this germline mutation in pri?miR-125a likely contributes to the genetic predisposition to gastric cancer by reducing the production of miR-125a, thereby interfering with the expression of miR-125a target genes.
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Fast and sequence-specific palladium-mediated cross-coupling reaction identified from phage display.
ACS Chem. Biol.
PUBLISHED: 07-24-2014
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Fast and specific bioorthogonal reactions are highly desirable because they provide efficient tracking of biomolecules that are present in low abundance and/or involved in fast dynamic process in living systems. Toward this end, classic strategy involves the optimization of substrate structures and reaction conditions in test tubes, testing their compatibility with biological systems, devising synthetic biology schemes to introduce the modified substrates into living cells or organisms, and finally validating the superior kinetics for enhanced capacity in tracking biomolecules in vivo--a lengthy process often mired by unexpected results. Here, we report a streamlined approach in which the "microenvironment" of a bioorthogonal chemical reporter is exploited directly in biological systems via phage-assisted interrogation of reactivity (PAIR) to optimize not only reaction kinetics but also specificity. Using the PAIR strategy, we identified a short alkyne-containing peptide sequence showing fast kinetics (k2=13,000±2000 M(-1) s(-1)) in a palladium-mediated cross-coupling reaction. Site-directed mutagenesis studies suggested that the residues surrounding the alkyne moiety facilitate the assembly of a key palladium-alkyne intermediate along the reaction pathway. When this peptide sequence was inserted into the extracellular domain of epidermal growth factor receptor (EGFR), this reactive sequence directed the specific labeling of EGFR in live mammalian cells.
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Differential expression and regulation of Ido2 in the mouse uterus during peri-implantation period.
In Vitro Cell. Dev. Biol. Anim.
PUBLISHED: 07-22-2014
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Ido2 is involved in tryptophan catabolism and immunity, but its physiological functions remain poorly understood. This study was undertaken to examine the expression and regulation of Ido2 gene in mouse uterus during the peri-implantation period. The results showed that Ido2 mRNA was highly expressed on day 4 of pregnancy and in the delayed implantation uterus. On days 5-8 of pregnancy, a low level of Ido2 expression was observed in the uteri. Simultaneously, Ido2 mRNA was also lowly expressed in the decidualized uterus. In the uterine stromal cells, 8-Br-cAMP could inhibit the expression of Ido2 mRNA. Moreover, Ido2 mRNA expression was gradually decreased after the stromal cells were treated with estrogen and progesterone and reached a nadir at 96 h. Further study found that overexpression of Ido2 could downregulate the expression of decidualization marker genes PRL, IGFBP1, and Dtprp under in vitro decidualization, while inhibition of Ido2 with devo-1-methyl-tryptophan (D-1-MT) could upregulate the expression of these marker genes. Under in vitro decidualization, overexpression of Ido2 could suppress the proliferation of uterine stromal cells and elevate the expression of Bax and MMP2 genes. On the contrary, Ido2 inhibitor D-1-MT could enhance the proliferation of stromal cells and expression of Bcl2 gene but decline the Bax/Bcl2 ratio. In the uterine stromal cells, estrogen and progesterone could induce the expression of Ido2 mRNA. These data indicate that Ido2 may be important for mouse embryo implantation and decidualization.
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Rifampicin Loaded Mannosylated Cationic Nanostructured Lipid Carriers for Alveolar Macrophage-specific Delivery.
Pharm. Res.
PUBLISHED: 07-11-2014
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In this study, cationic mannosylated nanostructured lipid carriers (Man-NLCs) were developed for the targeted delivery of rifampicin to alveolar macrophages.
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[PPAR-? agonist inhibits the expressions of chemokines induced by IFN-? and TNF-? in renal tubular epithelial cells].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 07-09-2014
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To investigate the effect of peroxisome proliferator-activated receptor-? (PPAR-?) agonist 15d-PGJ2 on the expressions of CXCL9, CXCL10 and CXCL11 in renal tubular epithelial cells (HK-2) stimulated by interferon-? (IFN-?) plus tumor necrosis factor-? (TNF-?).
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Development of a 5-fluorouracil-loaded PLGA microsphere delivery system by a solid-in-oil-in-hydrophilic oil (S/O/hO) novel method for the treatment of tumors.
Oncol. Rep.
PUBLISHED: 04-30-2014
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Tumor treatment requires a long-term regimen of chemotherapy, and both surgical tumor resection and radiation therapy are also used. The present study aimed to develop a novel method for 5-fluorouracil (5-FU)-loaded microspheres which enhance the therapeutic effects of chemotherapy, the quality of life of patients and reduce chemotherapy systemic side-effects. The preparation of a 5-FU microsphere delivery system by a solid-in-oil-in-hydrophilic oil (S/O/hO) novel method was carried out and then in vitro and in vivo evaluation of the 5-FU-microsphere delivery system was conducted. The 5-FU microsphere delivery system prepared had sustained-release function and achieved local treatment efficacy for tumors. The encapsulation efficiency of the 5-FU microsphere delivery system was >90% [better than the fabrication method using water-in-oil-in-water (W/O/W)]. The drug release profile from the 5-FU-loaded sustained-release microsphere delivery system matched the pseudo zero-order equation for 30 days in vitro. The plasma concentration of 5-FU was higher than the water solution by subcutaneous injection. The tumor growth rate of rabbits using the 5-FU microsphere delivery system was much lower than the rate in rabbit using a subcutaneous injection of 5-FU water solution. The 5-FU-loaded sustained-release microspheres using the novel method (S/O/hO) is a potential and effective method with which to inhibit tumor growth.
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Validated LC-MS/MS method for the simultaneous determination of chlorambucil and its prodrug in mouse plasma and brain, and application to pharmacokinetics.
J Pharm Biomed Anal
PUBLISHED: 04-30-2014
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A simple, sensitive and rapid LC-MS/MS method was developed and validated for the simultaneous determination of chlorambucil (CHL) and the prodrug of chlorambucil (CHLS) in mouse plasma and brain tissue. Detection was performed on a Diamonsil ODS chromatography column using gradient elution with a mobile phase of 0.2% aqueous formic acid and acetonitrile. Mass spectrometry was carried out in multiple reaction monitoring mode using a positive electrospray ionization interface. Good linearity was found for CHLS and CHL in plasma and brain tissue in different linear ranges (r>0.9996). Intra-day and inter-day precision was within 9.11% and accuracy was not more than 11.07%. The validated method was successfully applied to the pharmacokinetic study of CHLS and CHL in mice after intravenous administration.
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Detection of Upper Airway Status and Respiratory Events by a Current Generation Positive Airway Pressure Device.
Sleep
PUBLISHED: 04-29-2014
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To compare a positive airway pressure (PAP) device's detection of respiratory events and airway status during device-detected apneas with events scored on simultaneous polysomnography (PSG).
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Effects of co-treatment with sulforaphane and autophagy modulators on uridine 5'-diphospho-glucuronosyltransferase 1A isoforms and cytochrome P450 3A4 expression in Caco-2 human colon cancer cells.
Oncol Lett
PUBLISHED: 04-25-2014
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Sulforaphane (SFN), which is highly enriched in cruciferous vegetables, has been investigated for its cancer chemopreventive properties and ability to induce autophagy. Uridine 5'-diphospho (UDP)-glucuronosyltransferase (UGT)1A induction is one of the mechanisms that is responsible for the cancer chemopreventive activity of SFN. The current study demonstrates that rapamycin may enhance the chemopreventive effects of SFN on Caco-2 cells; this may be partially attributed to nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2)- and human pregnane X receptor (hPXR)-mediated UGT1A1, UGT1A8 and UGT1A10 induction. These results indicate that targeting autophagy modulation may be a promising strategy for increasing the chemopreventive effects of SFN in cases of colon cancer.
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Using cholecystokinin to facilitate endoscopic clearance of large common bile duct stones.
World J. Gastroenterol.
PUBLISHED: 04-18-2014
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To evaluate the effect of cholecystokinin (CCK) during extracorporeal shockwave lithotripsy (ESWL) in the clearance of common bile duct (CBD) stones in endoscopic retrograde cholangiopancreatography (ERCP).
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Kudo's pit pattern classification for colorectal neoplasms: a meta-analysis.
World J. Gastroenterol.
PUBLISHED: 04-03-2014
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To analyze the current available evidence of Kudo's pit pattern classification for diagnosing colorectal neoplasms.
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Photoclick chemistry: a fluorogenic light-triggered in vivo ligation reaction.
Curr Opin Chem Biol
PUBLISHED: 03-27-2014
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The ability to use chemical reactivity to monitor and control biomolecular processes with a spatial and temporal precision motivated the development of light-triggered in vivo chemistries. To this end, the photoinduced tetrazole-alkene cycloaddition, also termed 'photoclick chemistry' offers a very rapid chemical ligation platform for the manipulation of biomolecules and matrices in vivo. Here we outline the recent developments in the optimization of this chemistry, ranging from the search for substrates that offer two-photon photoactivatability, superior reaction kinetics, and/or genetic encodability, to the study of the reaction mechanism. The applications of the photoclick chemistry in protein labeling in vitro and in vivo as well as in preparing 'smart' hydrogels for 3D cell culture are highlighted.
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Modified laparoscopic intragastric surgery and endoscopic full-thickness resection for gastric stromal tumor originating from the muscularis propria.
Surg Endosc
PUBLISHED: 03-27-2014
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This study aimed to evaluate the feasibility and security of the modified laparoscopic intragastric surgery (MLIGS) and the endoscopic full-thickness resection (EFR) for the treatment of gastric stromal tumors (GSTs) originating from the muscularis propria.
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Factors affecting blood pressure profile in pre and postmenopausal women with obstructive sleep apnea hypopnea syndrome.
Sleep Breath
PUBLISHED: 03-17-2014
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Obstructive sleep apnea hypopnea syndrome (OSAHS) is an independent risk factor for development of hypertension. Epidemiological surveys have found that risk of cardiovascular diseases increased in postmenopausal women. However, it is not well known about the profiles of hypertension of women with OSAHS in their different reproductive stages. This study aimed to investigate the difference of blood pressure profile between pre and postmenopausal women with OSAHS.
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Structure, function, and pathogenesis of SHP2 in developmental disorders and tumorigenesis.
Curr Cancer Drug Targets
PUBLISHED: 03-04-2014
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Src homology 2 (SH2)-containing protein tyrosine phosphatase 2 (SHP2), encoded by the human PTPN11 gene, is a ubiquitously expressed protein tyrosine phosphatase (PTP) that consists of two tandem Src homology (SH2) domains (N-SH2 and C-SH2), a PTP catalytic domain, and a C-terminal tail with tyrosyl phosphorylation sites. It plays critical roles in numerous cellular processes through the regulation of various signaling pathways in PTP catalytic activity-dependent and -independent manners. Dysfunction of SHP2 resulting from pathogenic mutations and aberrant expression leads to the dysregulation of multiple signaling pathways, thus contributing to different human disorders. Germline and somatic mutations in PTPN11 are involved in Noonan syndrome (NS), LEOPARD syndrome (LS), and hematological malignancies, as well as several solid tumors. In this report, we provide an overview of the current knowledge of the structure and function of SHP2, and further discuss the molecular and pathogenic mechanism of SHP2 in human diseases, with a special focus on tumorigenesis. Furthermore, we summarize that SHP2 might itself represent a potential drug target for cancer prevention and treatment. Ongoing research and development of SHP2-specific inhibitors would enhance this potential.
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Use of confocal laser endomicroscopy to predict relapse of ulcerative colitis.
BMC Gastroenterol
PUBLISHED: 02-24-2014
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Assessment of inflammatory activity in patients with ulcerative colitis (UC) is crucial to the prediction of relapse. Confocal laser endomicroscopy (CLE) is an accurate tool for assessing inflammatory activity in UC patients. This study aimed to evaluate whether CLE could be used to predict UC relapse reliably.
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Macrophage migration inhibitory factor is overexpressed in pancreatic cancer tissues and impairs insulin secretion function of ?-cell.
J Transl Med
PUBLISHED: 02-17-2014
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Understanding the pathogenic mechanism of pancreatic cancer associated diabetes (PCDM) might help yield biomarkers for the early diagnosis of pancreatic cancer (PC) from population with new-onset diabetes. In the current study, we sought to determine the role of macrophage migration inhibitory factor (MIF) in PCDM pathogenesis.
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Increased gap density predicts weakness of the epithelial barrier in vivo by confocal laser endomicroscopy in indomethacin-induced enteropathy.
Dig. Dis. Sci.
PUBLISHED: 02-11-2014
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The intestinal epithelial barrier plays an important role in the pathogenesis of non-steroidal anti-inflammatory drug-induced enteropathy, and its disruption is often associated with increased cell shedding. The purpose of this report is to observe the gap density in indomethacin-induced small intestinal damage by confocal laser endomicroscopy (CLE) and to investigate the mechanisms involved in this process and how mucosal protectants improve intestinal epithelial barrier dysfunction. CLE is expected to provide a new way for evaluating non-steroidal anti-inflammatory drugs-induced enteropathy in humans and assessing drug efficacy.
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Confocal laser endomicroscopy for in vivo detection of gastric intestinal metaplasia: a randomized controlled trial.
Endoscopy
PUBLISHED: 01-28-2014
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Gastric intestinal metaplasia (GIM) is associated with a risk for development of intestinal-type gastric cancer. This study aimed to compare the diagnostic yield of GIM from confocal laser endomicroscopy (CLE) and white light endoscopy (WLE).
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Protective immunity conferred by porcine circovirus 2 ORF2-based DNA vaccine in mice.
Microbiol. Immunol.
PUBLISHED: 01-25-2014
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Post-weaning multisystemic wasting syndrome (PMWS) associated with porcine circovirus type 2 (PCV2) has caused the swine industry significant health challenges and economic damage. Although inactivated and subunit vaccines against PMWS have been used widely, so far no DNA vaccine is available. In this study, with the aim of exploring a new route for developing a vaccine against PCV2, the immunogenicity of a DNA vaccine was evaluated in mice. The pEGFP-N1 vector was used to construct a PCV2 Cap gene recombinant vaccine. To assess the immunogenicity of pEGFP-Cap, 80 BALB/c mice were immunized three times at 2 weekly intervals with pEGFP-Cap, LG-strain vaccine, pEGFP-N1 vector or PBS and then challenged with PCV2. IgG and cytokines were assessed by indirect ELISA and ELISA, respectively. Specimens stained with hematoxylin and eosin (HE) and immunohistochemistry (IHC) techniques were examined histopathologically. It was found that vaccination of the mice with the pEGFP-Cap induced solid protection against PCV2 infection through induction of highly specific serum IgG antibodies and cytokines (IFN-? and IL-10), and a small PCV2 viral load. The mice treated with the pEGFP-Cap and LG-strain developed no histopathologically detectable lesions (HE stain) and IHC techniques revealed only a few positive cells. Thus, this study demonstrated that recombinant pEGFP-Cap substantially alleviates PCV2 infection in mice and provides evidence that a DNA vaccine could be an alternative to PCV2 vaccines against PMWS.
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Light manipulation for organic optoelectronics using bio-inspired moth's eye nanostructures.
Sci Rep
PUBLISHED: 01-24-2014
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Organic-based optoelectronic devices, including light-emitting diodes (OLEDs) and solar cells (OSCs) hold great promise as low-cost and large-area electro-optical devices and renewable energy sources. However, further improvement in efficiency remains a daunting challenge due to limited light extraction or absorption in conventional device architectures. Here we report a universal method of optical manipulation of light by integrating a dual-side bio-inspired moth's eye nanostructure with broadband anti-reflective and quasi-omnidirectional properties. Light out-coupling efficiency of OLEDs with stacked triple emission units is over 2 times that of a conventional device, resulting in drastic increase in external quantum efficiency and current efficiency to 119.7% and 366?cd A(-1) without introducing spectral distortion and directionality. Similarly, the light in-coupling efficiency of OSCs is increased 20%, yielding an enhanced power conversion efficiency of 9.33%. We anticipate this method would offer a convenient and scalable way for inexpensive and high-efficiency organic optoelectronic designs.
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Pharmacological mobilization of endogenous stem cells significantly promotes skin regeneration after full-thickness excision: the synergistic activity of AMD3100 and tacrolimus.
J. Invest. Dermatol.
PUBLISHED: 01-23-2014
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Stem cell therapy has shown promise in treating a variety of pathologies including skin wounds, but practical applications remain elusive. Here, we demonstrate that endogenous stem cell mobilization produced by AMD3100 and low-dose tacrolimus is able to reduce by 25% the time of complete healing of full-thickness wounds created by surgical excision. Equally important, healing was accompanied by reduced scar formation and regeneration of hair follicles. Searching for mechanisms, we found that AMD3100 combined with low-dose tacrolimus mobilized increased number of lineage-negative c-Kit+, CD34+, and CD133+ stem cells. Low-dose tacrolimus also increased the number of SDF-1-bearing macrophages in the wound sites amplifying the "pull" of mobilized stem cells into the wound. Lineage tracing demonstrated the critical role of CD133 stem cells in enhanced capillary and hair follicle neogenesis, contributing to more rapid and perfect healing. Our findings offer a significant therapeutic approach to wound healing and tissue regeneration.
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Levels of lymphocyte subsets in peripheral blood prior treatment are associated with aggressive breast cancer phenotypes or subtypes.
Med. Oncol.
PUBLISHED: 01-19-2014
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The aim of this study was to assess associations between ER, Ki67, Her-2 phenotypes, molecular subtypes of breast cancer and circulating levels of lymphocyte subsets (CD4+, CD8+, NK, CD19+, CD20+) and the ratio of CD4+ to CD8+ prior to treatment. Cells from peripheral blood were counted by flow cytometry, ER, Her-2, and Ki67 expressions were detected by pathological examination, and Her-2 was also detected by FISH. We conducted a case-case comparison of 494 women with newly diagnosed breast cancer to evaluate association between levels of lymphocyte subsets in peripheral blood and breast cancer phenotypes [ER- vs. ER+; Ki67 ? 14 % vs. Ki67 < 14 %; Her-2+ vs. Her-2-; triple-negative breast cancer (TNBC) vs. luminal A]. Women with the highest levels of CD3+ (OR 0.45, 95 % CI 0.22-0.94), CD4+ (OR 0.22, 95 % CI 0.08-0.59), and the ratio of CD4+/CD8+ (OR 0.17, 95 % CI 0.06-0.47) were least likely to have TNBCs compared with luminal A cancers. The highest tertile of CD8+ (OR 3.67, 95 % CI 1.06-12.72) and NK (OR 2.64, 95 % CI 1.12-6.24) was significantly associated with TNBC compared with luminal A cancer. ER-, Ki67 ? 14 %, Her-2+ were associated with low levels of CD4+ and CD4+/CD8+ compared with ER+, Ki67 < 14 %, Her-2-. Women in the highest level of CD8+ had more likelihood to have ER- and Her-2+ compared with ER+ and Her-2-. High levels of NK cells were associated with increased risk of ER- compared with ER+ cancers. Highest levels of CD19+ and CD20+ were associated with low risk of ER-, compared with ER+ cancers. These findings show that immune function differs among different breast cancer phenotypes or subtypes and is associated with ER-, Her-2+, Ki67 ? 14 %, and TNBC which are likely to be aggressive phenotypes.
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Diagnosing Helicobacter pylori infection in vivo by novel endoscopic techniques.
World J. Gastroenterol.
PUBLISHED: 01-16-2014
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Infection with Helicobacter pylori (H. pylori) is a worldwide problem. Endoscopic observation of H. pylori infection in vivo would be helpful to obtain an immediate diagnosis. The aim of this review is to describe recent advances in endoscopic technology and to review the available literature pertaining to its clinical application in H. pylori infection. Endoscopic visualization of H. pylori infection is not always feasible using conventional endoscopy. Thus, advanced endoscopic techniques have been developed with the aim of providing a precise and ''real-time'' endoscopic diagnosis. Recently, new endoscopic techniques such as magnifying endoscopy, narrow band imaging, I-Scan, endocytoscopy and endomicroscopy help focus examination of the stomach to diagnose disease in a time-ef?cient manner, and the analysis of mucosal surface details is beginning to resemble histologic examination. The new detailed images have enabled endoscopists to observe microscopic structures, such as gastric pit patterns, microvessels and cell morphology. Accordingly, endoscopic prediction of H. pylori infection is possible by analysis of surface architecture of the mucosa, which in?uences the clinical management. These endoscopic techniques might lead us to easier diagnosis and treatment of H. pylori-related diseases.
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The effect of non-benzodiazepine hypnotics on sleep quality and severity in patients with OSA: a meta-analysis.
Sleep Breath
PUBLISHED: 01-14-2014
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Although there is a high co-occurrence of insomnia and obstructive sleep apnea (OSA), the administration of sedative hypnotics in patients with OSA is still inconsistent. The aim is to study the effect of non-benzodiazepine hypnotics (non-BZDs) on sleep quality and severity in patients with OSA.
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Enteric glial cells and their role in the intestinal epithelial barrier.
World J. Gastroenterol.
PUBLISHED: 01-12-2014
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The intestinal epithelium constitutes a physical and functional barrier between the external environment and the host organism. It is formed by a continuous monolayer of intestinal epithelial cells maintained together by intercellular junctional complex, limiting access of pathogens, toxins and xenobiotics to host tissues. Once this barrier integrity is disrupted, inflammatory disorders and tissue injury are initiated and perpetuated. Beneath the intestinal epithelial cells lies a population of astrocyte-like cells that are known as enteric glia. The morphological characteristics and expression markers of these enteric glia cells were identical to the astrocytes of the central nervous system. In the past few years, enteric glia have been demonstrated to have a trophic and supporting relationship with intestinal epithelial cells. Enteric glia lesions and/or functional defects can be involved in the barrier dysfunction. Besides, factors secreted by enteric glia are important for the regulation of gut barrier function. Moreover, enteric glia have an important impact on epithelial cell transcriptome and induce a shift in epithelial cell phenotype towards increased cell adhesion and cell differentiation. Enteric glia can also preserve epithelial barrier against intestinal bacteria insult. In this review, we will describe the current body of evidence supporting functional roles of enteric glia on intestinal barrier.
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Intestinal obstruction due to migration of a thermometer from bladder to abdominal cavity: a case report.
World J. Gastroenterol.
PUBLISHED: 01-08-2014
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Intraperitoneal foreign bodies such as retained surgical instruments can cause intestinal obstruction. However, intestinal obstruction due to transmural migration of foreign bodies has rarely been reported. Here, we report a case of intestinal obstruction due to a clinical thermometer which migrated from the bladder into the abdominal cavity. A 45-year-old man was admitted to our hospital with a one-year history of recurrent lower abdominal cramps. Two days before admission, the abdominal cramps aggravated. Intestinal obstruction was confirmed with upright abdominal radiography and computerized tomography scan which showed dilation of the small intestines and a thermometer in the abdominal cavity. Then laparotomy was performed. A scar was observed at the fundus of the bladder and a thermometer was adhering to the small bowels and mesentery which resulted in intestinal obstruction. Abdominal cramps were eliminated and defecation and flatus recovered soon after removal of the thermometer.
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CD26/DPP4 Cell-Surface Expression in Bat Cells Correlates with Bat Cell Susceptibility to Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Infection and Evolution of Persistent Infection.
PLoS ONE
PUBLISHED: 01-01-2014
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Middle East respiratory syndrome coronavirus (MERS-CoV) is a recently isolated betacoronavirus identified as the etiologic agent of a frequently fatal disease in Western Asia, Middle East respiratory syndrome. Attempts to identify the natural reservoirs of MERS-CoV have focused in part on dromedaries. Bats are also suspected to be reservoirs based on frequent detection of other betacoronaviruses in these mammals. For this study, ten distinct cell lines derived from bats of divergent species were exposed to MERS-CoV. Plaque assays, immunofluorescence assays, and transmission electron microscopy confirmed that six bat cell lines can be productively infected. We found that the susceptibility or resistance of these bat cell lines directly correlates with the presence or absence of cell surface-expressed CD26/DPP4, the functional human receptor for MERS-CoV. Human anti-CD26/DPP4 antibodies inhibited infection of susceptible bat cells in a dose-dependent manner. Overexpression of human CD26/DPP4 receptor conferred MERS-CoV susceptibility to resistant bat cell lines. Finally, sequential passage of MERS-CoV in permissive bat cells established persistent infection with concomitant downregulation of CD26/DPP4 surface expression. Together, these results imply that bats indeed could be among the MERS-CoV host spectrum, and that cellular restriction of MERS-CoV is determined by CD26/DPP4 expression rather than by downstream restriction factors.
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Oxygen-carbon nanotubes as a chemotherapy sensitizer for paclitaxel in breast cancer treatment.
PLoS ONE
PUBLISHED: 01-01-2014
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To study the in vivo and in vitro effects of adding oxygen carbon nanotubes (CNTs) to chemotherapy for breast cancer.
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Learning curve and interobserver agreement of confocal laser endomicroscopy for detecting precancerous or early-stage esophageal squamous cancer.
PLoS ONE
PUBLISHED: 01-01-2014
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Confocal laser endomicroscopy (CLE) can provide in vivo subcellular resolution images of esophageal lesions. However, the learning curve in interpreting CLE images of precancerous or early-stage esophageal squamous cancer is unknown. The goal of this study is to evaluate the diagnostic accuracy and inter-observer agreement for differentiating esophageal lesions in CLE images among experienced and inexperienced observers and to assess the learning curve.
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Disappearance of GFP-positive hepatocytes transplanted into the liver of syngeneic wild-type rats pretreated with retrorsine.
PLoS ONE
PUBLISHED: 01-01-2014
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Green fluorescent protein (GFP) is a widely used molecular tag to trace transplanted cells in rodent liver injury models. The differing results from various previously reported studies using GFP could be attributed to the immunogenicity of GFP.
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Differential expression and regulation of Tdo2 during mouse decidualization.
J. Endocrinol.
PUBLISHED: 11-06-2013
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Tryptophan 2,3-dioxygenase (Tdo2) is a rate-limiting enzyme which directs the conversion of tryptophan to kynurenine. The aim of this study was to examine the expression and regulation of Tdo2 in mouse uterus during decidualization. Tdo2 mRNA was mainly expressed in the decidua on days 6-8 of pregnancy. By real-time PCR, a high level of Tdo2 expression was observed in the uteri from days 6 to 8 of pregnancy, although Tdo2 expression was observed on days 1-8. Simultaneously, Tdo2 mRNA was also detected under in vivo and in vitro artificial decidualization. Estrogen, progesterone, and 8-bromoadenosine-cAMP could induce the expression of Tdo2 in the ovariectomized mouse uterus and uterine stromal cells. Tdo2 could regulate cell proliferation and stimulate the expression of decidual marker Dtprp in the uterine stromal cells and decidual cells. Overexpression of Tdo2 could upregulate the expression of Ahr, Cox2, and Vegf genes in uterine stromal cells, while Tdo2 inhibitor 680C91 could downregulate the expression of Cox2 and Vegf genes in uterine decidual cells. These data indicate that Tdo2 may play an important role during mouse decidualization and be regulated by estrogen, progesterone, and cAMP.
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Fluorogenic, two-photon-triggered photoclick chemistry in live mammalian cells.
J. Am. Chem. Soc.
PUBLISHED: 10-31-2013
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The tetrazole-based photoclick chemistry has provided a powerful tool to image proteins in live cells. To extend photoclick chemistry to living organisms with improved spatiotemporal control, here we report the design of naphthalene-based tetrazoles that can be efficiently activated by two-photon excitation with a 700 nm femtosecond pulsed laser. A water-soluble, cell-permeable naphthalene-based tetrazole was identified that reacts with acrylamide with the effective two-photon cross-section for the cycloaddition reaction determined to be 3.8 GM. Furthermore, the use of this naphthalene-tetrazole for real-time, spatially controlled imaging of microtubules in live mammalian cells via the fluorogenic, two-photon-triggered photoclick chemistry was demonstrated.
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Bioorthogonal chemistry: strategies and recent developments.
Chem. Commun. (Camb.)
PUBLISHED: 10-23-2013
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The use of covalent chemistry to track biomolecules in their native environment-a focus of bioorthogonal chemistry-has received considerable interest recently among chemical biologists and organic chemists alike. To facilitate wider adoption of bioorthogonal chemistry in biomedical research, a central effort in the last few years has been focused on the optimization of a few known bioorthogonal reactions, particularly with respect to reaction kinetics improvement, novel genetic encoding systems, and fluorogenic reactions for bioimaging. During these optimizations, three strategies have emerged, including the use of ring strain for substrate activation in the cycloaddition reactions, the discovery of new ligands and privileged substrates for accelerated metal-catalysed reactions, and the design of substrates with pre-fluorophore structures for rapid "turn-on" fluorescence after selective bioorthogonal reactions. In addition, new bioorthogonal reactions based on either modified or completely unprecedented reactant pairs have been reported. Finally, increasing attention has been directed toward the development of mutually exclusive bioorthogonal reactions and their applications in multiple labeling of a biomolecule in cell culture. In this feature article, we wish to present the recent progress in bioorthogonal reactions through the selected examples that highlight the above-mentioned strategies. Considering increasing sophistication in bioorthogonal chemistry development, we strive to project several exciting opportunities where bioorthogonal chemistry can make a unique contribution to biology in the near future.
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[Simultaneous determination of formononetin, calycosin and isorhamnetin from Astragalus mongholicus in rat plasma by LC-MS/MS and application to pharmacokinetic study].
Zhong Yao Cai
PUBLISHED: 10-19-2013
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To establish a method to determine the concentration of formononetin, calycosin and isorhamnetin from Astragalus mongholicus in rats plasma using LC-MS/MS and calculate their pharmacokinetic parameters.
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An S-Domain Receptor-Like Kinase, OsSIK2, Confers Abiotic Stress Tolerance and Delays Dark-Induced Leaf Senescence in Rice.
Plant Physiol.
PUBLISHED: 10-18-2013
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Receptor-like kinases play important roles in plant development and defense responses; however, their functions in other processes remain unclear. Here, we report that OsSIK2, an S-domain receptor-like kinase from rice (Oryza sativa), is involved in abiotic stress and the senescence process. OsSIK2 is a plasma membrane-localized protein with kinase activity in the presence of Mn(2+). OsSIK2 is expressed mainly in rice leaf and sheath and can be induced by NaCl, drought, cold, dark, and abscisic acid treatment. Transgenic plants overexpressing OsSIK2 and mutant sik2 exhibit enhanced and reduced tolerance to salt and drought stress, respectively, compared with the controls. Interestingly, a truncated version of OsSIK2 without most of the extracellular region confers higher salt tolerance than the full-length OsSIK2, likely through the activation of different sets of downstream genes. Moreover, seedlings of OsSIK2-overexpressing transgenic plants exhibit early leaf development and a delayed dark-induced senescence phenotype, while mutant sik2 shows the opposite phenotype. The downstream PR-related genes specifically up-regulated by full-length OsSIK2 or the DREB-like genes solely enhanced by truncated OsSIK2 are all induced by salt, drought, and dark treatments. These results indicate that OsSIK2 may integrate stress signals into a developmental program for better adaptive growth under unfavorable conditions. Manipulation of OsSIK2 should facilitate the improvement of production in rice and other crops.
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Design and synthesis of laser-activatable tetrazoles for a fast and fluorogenic red-emitting 1,3-dipolar cycloaddition reaction.
Org. Lett.
PUBLISHED: 10-10-2013
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The design and synthesis of a new class of laser light activatable tetrazoles with extended ?-systems is reported. Upon 405 nm laser light irradiation, these bithiophene-substituted tetrazoles underwent extremely fast 1,3-dipolar cycloaddition reactions with dimethyl fumarate with second-order rate constants approaching 4000 M(-1) s(-1). The resulting pyrazoline cycloadducts exhibited solvent-dependent red fluorescence, making these tetrazoles potentially useful as fluorogenic probes for detecting alkenes in vivo.
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Enhanced performance of semitransparent inverted organic photovoltaic devices via a high reflector structure.
ACS Appl Mater Interfaces
PUBLISHED: 10-04-2013
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Significantly enhanced performances of semitransparent inverted organic photovoltaic devices have been realized by simply introducing a high reflector structure, which comprises several pairs of MoO3/LiF with a thickness of 60 nm for MoO3 and 90 nm for LiF, respectively. After optimizing the reflector structure, the enhanced light harvesting is achieved, and thus the increased optical current is obtained. The short-circuit current density (JSC) and power conversion efficiency (PCE) are increased to 10.9 mA cm(-2) and 4.32%, compared to 8.09 mA cm(-2) and 3.36% in the control device. This leads to a 30% enhancement in PCE. According to the experimental and simulated results, the improved performance is attributed to the effective reflection of light at the wavelength from 450 to 600 nm, which corresponds to the absorption range of the active layer. The demonstrated light-trapping approach is expected to be an effective method to realize the high efficiency in semitransparent organic photovoltaic devices.
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Design of oligothiophene-based tetrazoles for laser-triggered photoclick chemistry in living cells.
Chem. Commun. (Camb.)
PUBLISHED: 09-16-2013
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A 405 nm light-activatable terthiophene-based tetrazole was designed that reacts with a fumarate dipolarophile with the second-order rate constant k2 exceeding 10(3) M(-1) s(-1). The utility of this laser-activatable tetrazole in imaging microtubules in a spatiotemporally controlled manner in live cells was demonstrated.
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[Study on effect of psoralidin on anti-experimental postmenopausal osteoporosis and its mechanism].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-10-2013
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To observe the effect of psoralidine in rats with ovariectomy, and preliminarily study its mechanism.
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[The optimation of extraction technology of chuanxiong and xiangfu compatibility by SFE-CO2].
Zhong Yao Cai
PUBLISHED: 08-02-2013
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To optimize the extraction conditions of Chuanxiong and Xiangfu compatibility by supercritical CO2 and control the quality of the extract.
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Novel LC-MS/MS method for analyzing imperialine in rat plasma: development, validation, and application to pharmacokinetics.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 07-25-2013
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A sensitive, selective, rapid liquid chromatography-electrospray ionization-tandem mass spectrometric method was developed and validated in rat plasma to quantify imperialine, a major active constituent extracted from Bulbus Fritillariae Cirrhosae. Before analysis, plasma samples were pre-treated using cost-effective protein precipitation in order to extract imperialine and the internal standard, carbamzepine. The two analytes were then separated on a Diamonsil ODS chromatography column using gradient elution with a mobile phase of 0.1% aqueous formic acid and acetonitrile. Mass spectrometry was carried out in multiple reaction monitoring mode using a positive electrospray ionization interface. The calibration curve was linear (r(2)=0.9998) over the concentration range 2-1000ng/mL, while the validated limit of determination (LOD) was 0.5ng/mL. Precision varied from 0.1% to 7.1%, and the accuracy varied within ±2%. The method proved robust to sample freezing and thawing, as well as short- and long-term sample storage. The developed method was successfully applied to the pharmacokinetic study of imperialine in rats. Different amounts of imperialine were administered in single doses orally or through the caudal vena cava, and pharmacokinetic parameters were evaluated. Oral bioavailability with a dose of 1mg/kg was 31.2%; 5mg/kg, 53.6%; and 10mg/kg, 47.4%.
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Efficacy of mouth opening exercises in treating trismus after maxillectomy.
Chin. Med. J.
PUBLISHED: 07-24-2013
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Patients with maxillary tumor often suffer from trismus after maxillectomy, which could turn out to be a permanent sequela without proper intervention. In this study, the efficacy of mouth opening exercises in preventing and treating trismus was observed in patients with maxillary tumor early after their operations. At the same time, radiotherapy as an influencing factor for the mouth opening exercises was evaluated.
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PRDM16 rs2651899 Variant Is a Risk Factor for Chinese Common Migraine Patients.
Headache
PUBLISHED: 07-22-2013
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Recent genome-wide association studies (GWAS) have identified 3 loci in or near PRDM16 (1p36.32, rs2651899), LRP1 (12q13.3, rs11172113) and TRPM8 (2q37.1, rs10166942) in the population-based Womens Genome Health Study (WGHS) of migraine, and 2 loci in or near TRPM8 and LRP1 were repeated in European GWAS study. To evaluate whether the same variants are related to migraine in Chinese population, we investigated migraine with aura (MA) and migraine without aura (MO) patients of Chinese Han ethnicity in mainland China.
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[Value of 3-dimensional speckle tracking imaging to quantify regional left ventricular function in patients with coronary artery disease].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 07-15-2013
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To assess left ventricular (LV) strain by 3-dimensional speckle tracking imaging (3D-STI) in patients with coronary heart disease (CHD).
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Expression Levels and Significance of Nuclear Factor-?B and Epidermal Growth Factor Receptor in Hepatolithiasis Associated with Intrahepatic Cholangiocarcinoma.
Dig Surg
PUBLISHED: 07-14-2013
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Background: An increasing incidence of cholangiocarcinoma (CCA) and CCA mortality rates has been observed around the world. Patients with intrahepatic biliary stones have a 10% risk of developing CCA, and up to 70% of patients with histologically confirmed CCA have hepatolithiasis. Few previous studies have addressed the associations between the expression of nuclear factor (NF)-?B and epidermal growth factor receptor (EGFR) and clinicopathological prognosis in patients with hepatolithiasis-associated intrahepatic CCA. Aims: This study was designed to investigate the clinicopathological and prognostic significance of NF-?B and EGFR expression in hepatolithiasis-associated intrahepatic CCA and hepatolithiasis. Methods: A total of 90 liver specimens were immunohistochemically stained for NF-?B and EGFR expression, and the characteristics of 90 individual patients were retrospectively reviewed. Results: Differences in the positive rates of NF-?B and EGFR expression between the hepatolithiasis-associated intrahepatic CCA group, intrahepatic lithiasis group, and control group were found to be statistically significant. EGFR expression was closely associated with the degree of differentiation and depth of invasion (p < 0.05). The 1-, 3-, and 5-year overall survival rates were respectively 42.8, 21.0, and 10.3% in intrahepatic CCA groups. The survival rate of the EGFR-negative group was higher than in the EGFR-positive group (p < 0.01). Lymph node metastasis (HR 1.24, 95% CI 1.02-1.51) and EGFR positivity (HR 1.74, 95% CI 1.30-2.23) were associated with decreases in the survival rate. Conclusion: The expression of NF-?B may be an early step in intrahepatic cholangiocarcinogenesis. Overexpression of EGFR is associated with the degree of malignancy and with poor prognosis. NF-?B and EGFR may cooperate during intrahepatic cholangiocarcinogenesis and progression. Lymph node metastasis and EGFR positivity were associated with decreases in the survival rate.
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Human ABCB1 (P-glycoprotein) and ABCG2 mediate resistance to BI 2536, a potent and selective inhibitor of Polo-like kinase 1.
Biochem. Pharmacol.
PUBLISHED: 07-02-2013
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The overexpression of the serine/threonine specific Polo-like kinase 1 (Plk1) has been detected in various types of cancer, and thus has fast become an attractive therapeutic target for cancer therapy. BI 2536 is the first selective inhibitor of Plk1 that inhibits cancer cell proliferation by promoting G2/M cell cycle arrest at nanomolar concentrations. Unfortunately, alike most chemotherapeutic agents, the development of acquired resistance to BI 2536 is prone to present a significant therapeutic challenge. One of the most common mechanisms for acquired resistance in cancer chemotherapy is associated with the overexpression of ATP-binding cassette (ABC) transporters ABCB1, ABCC1 and ABCG2. Here, we discovered that overexpressing of either ABCB1 or ABCG2 is a novel mechanism of acquired resistance to BI 2536 in human cancer cells. Moreover, BI 2536 stimulates the ATPase activity of both ABCB1 and ABCG2 in a concentration-dependent manner, and inhibits the drug substrate transport mediated by these transporters. More significantly, the reduced chemosensitivity and BI 2536-mediated G2/M cell cycle arrest in cancer cells overexpressing either ABCB1 or ABCG2 can be significantly restored in the presence of selective inhibitor or other chemotherapeutic agents that also interact with ABCB1 and ABCG2, such as tyrosine kinase inhibitors nilotinib and lapatinib. Taken together, our findings indicate that in order to circumvent ABCB1 or ABCG2-mediated acquired resistance to BI 2536, a combined regimen of BI 2536 and inhibitors or clinically active drugs that potently inhibit the function of ABC drug transporters, should be considered as a potential treatment strategy in the clinic.
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[Effects of autophagy modulator on autophagy and uridine 5-diphospho-glucuronosyltransferase 1A1 induced by sulforaphane].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-14-2013
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To explore the effects of 3-methyladenine (3-MA) and rapamycin (Rapa) on autophagy and uridine 5-diphospho-glucuronosyltransferase 1A1 (UGT1A1) induced by sulforaphane (SFN) in human colon cancer Caco-2 cells.
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Early clinical features and diagnosis of Dravet syndrome in 138 Chinese patients with SCN1A mutations.
Brain Dev.
PUBLISHED: 05-05-2013
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Objective: To summarize the early clinical features of Dravet syndrome (DS) patients with SCN1A gene mutations before the age of one. Methods: SCN1A gene mutation screening was performed by PCR-DNA sequencing and multiple ligation-dependent probe amplication (MLPA). The early clinical features of DS patients with SCN1A mutations were reviewed with attention to the seizures induced by fever and other precipitating factors before the first year of life. Results: The clinical data of 138 DS patients with SCN1A gene mutations were reviewed. The median seizure onset age was 5.3months. Ninety-nine patients (71.7%) experienced seizures with duration more than 15min in the first year of life. Two or more seizures induced by fever within 24h or the same febrile illness were observed in 93 patients (67.4%). 111 patients (80.4%) had hemi-clonic and (or) focal seizures. Seizures had been triggered by fever of low degree (T<38°C) in 62.3% (86/138) before the first year of life. Vaccine-related seizures were observed in 34.8% (48/138). Seizures in 22.5% (31/138) of patients were triggered by hot bath. Carbamazepine, oxcarbazepine, lamotrigine, phenobarbital and phenytoin showed either no effect or exacerbating the seizures in our group. Conclusion: The seizure onset age in DS patients was earlier than that was in common febrile seizures. When a baby exhibits two or more features of complex febrile seizures in the first year of life, a diagnosis of DS should be considered, and SCN1A gene mutation screening should be performed as early as possible. Early diagnosis of DS will help clinicians more effectively prescribe antiepileptic drugs for stronger prognosis.
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Establishment and characterization of dairy cow growth hormone secreting anterior pituitary cell model.
In Vitro Cell. Dev. Biol. Anim.
PUBLISHED: 04-17-2013
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A dairy cow anterior pituitary cell (DCAPC) model was established in vitro for the study of growth hormone (GH) synthesis and secretion in the anterior pituitary gland of the dairy cow. Pituitary glands were obtained from Holstein dairy cows heads cut by electric saw, and the posterior pituitary glands were removed to obtain integrated anterior pituitary glands. Immunohistochemistry assay of GH in the anterior pituitary glands showed that most somatotrophs were located within the lateral wings of the anterior pituitary. Tissues of the lateral wings of the anterior pituitary were dispersed and cultured in Dulbeccos modified Eagles medium supplemented with 10% fetal bovine serum. The DCAPCs displayed a monolayer, cobblestone, epithelial-like morphology which are the typical characteristics of the anterior pituitary cells. The DCAPCs were subcultured continuously over ten passages. GH immunoreactivity was present in DCAPCs at passage 10. The transcription of the bovine GH mRNA in DCAPCs at passage 10 was decreased to below 50% compared with the lateral wings of the anterior pituitary tissues. Thus, our DCAPCs model is effective for the in vitro examination of GH synthesis and secretion in the dairy cow anterior pituitary gland. The effects of transforming growth factor beta 1 (TGF-?1) and interferon-? (IFN-?) on the expression of GH mRNA in DCAPCs at passage 3 were also investigated. There were no obvious changes in transcription of the GH gene after treatment with TGF-?1 for 24 h, while IFN-? increased transcription of the GH gene in a dose-dependent manner.
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Magnified and enhanced computed virtual chromoendoscopy in gastric neoplasia: a feasibility study.
World J. Gastroenterol.
PUBLISHED: 03-28-2013
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To evaluate the feasibility of a new computed virtual chromoendoscopy (CVC) device (M i-scan) in the diagnosis of gastric neoplasia.
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Molecular characterization of the planktonic microorganisms in water of two mountain brackish lakes.
J. Basic Microbiol.
PUBLISHED: 03-05-2013
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The prokaryotic diversity in two brackish lakes (Sayram Lake and Chaiwopu Lake) was investigated by constructing bacterial and archaeal clone libraries of 16S rRNA genes. Bacterial clones from Sayram Lake were classified into six phyla (Proteobacteria, Verrucomicrobia, Bacteroidetes, Planctomycetes, Acidobacteria, Actinobacteria). Of these, Proteobacteria and Verrucomicrobia were the most dominant, representing 50.4 and 16.8% of the clone library, respectively. Sequences related to Proteobacteria (58.1%), Cyanobacteria (17.2%), Bacteroidetes (15%), Verrucomicrobia (4.3%), Actinobacteria (3.2%) constituted over 97% of the bacterial clone library from Chaiwopu Lake. In addition, 58.8% (Sayram Lake) and 48% (Chaiwopu Lake) of bacterial clones showed high sequence identity to pure cultures. The composition of Archaea was obviously different between the two lakes. Only the Crenarchaeota phylum was found in the Sayram Lake, whereas Archaeal sequences from Chaiwopu Lake were classified into three phyla: Crenarchaeota (5.8%), Thaumarchaeota (81.2%), and Euryarchaeota (13%). Among the archaeal sequences, 94.2% were highly related to cultivable species of the genus Nitrosopumilus, Methanoculleus, and Methanobacterium. These results showed a high diversity of potential cultivable heterotrophic bacteria in Sayram Lake and Chaiwopu Lake. Chaiwopu Lake was a source of potentially novel, cultivable archaea.
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