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Find video protocols related to scientific articles indexed in Pubmed.
Deep-red phosphorescent iridium(III) complexes containing 1-(benzo[b] thiophen-2-yl) isoquinoline ligand: synthesis, photophysical and electrochemical properties and DFT calculations.
J Fluoresc
PUBLISHED: 08-31-2014
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Four new bis-cyclometalated iridium(III) complexes, [Ir(btq) 2phen] [PF6] (3a), [Ir(btq) 2bpy] [PF6] (3b), [Ir(btq) 2dtbipy] [PF6] (3c) and [Ir(btq) 2pic] (3d) (btq?=?1-(benzo[b] thiophen-2-yl) isoquinoline, phen?=?1,10-phenanthroline, bpy?=?2,2'-bipyridine, dtbipy?=?4,4'-di-tert-butyl-2,2'-bipyridine, pic?=?picolinic acid) have been synthesized and fully characterized. The crystal structure of 3a has been determined by X-ray analysis. The photophysical and electrochemical properties of these new complexes 3a?-?3d have been studied. The photoluminescence spectra of all Ir(III) complexes exhibit deep-red emission maxima at 682, 682, 683 and 698 nm, respectively. The most representative molecular orbital energy-level diagrams and the lowest energy electronic transitions of 3a?-?3d have been calculated with density functional theory (DFT) and time-dependent DFT (TD?-?DFT). The results show that the pic ancillary ligand of complex 3d influences the absorption and emission energies with a further red-shift relative to other three complexes 3a?-?3c.
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Spatial localization of the JAG1/Notch1/osteopontin cascade modulates extrahepatic metastasis in hepatocellular carcinoma.
Int. J. Oncol.
PUBLISHED: 08-29-2014
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The model of Notch-driven carcinogenesis and development of hepatocellular carcinoma remains controversial and is based on observations of developmental stage- and dose-dependent Notch activation. In this study, the relevance of the spatial distribution of Notch cascade members to the promotion of hepatocellular carcinoma metastasis was evaluated. The spatial expression patterns of the members of the Jagged1 (JAG1)/Notch1 cascade in HCC were evaluated in a tissue microarray of 112 tumors and 46 peri-tumors. Regulation of JAG1/Notch1 on osteopontin (OPN) was evaluated by RNA interference. Tumor cells with JAG1 expressed on the membrane (JAG1(Mem)) were more likely to undergo extrahepatic metastasis [p<0.001; hazard ratio (HR), 0.166; 95% CI, 0.068-0.402], and JAG1(Mem) was a strong independent prognostic factor for metastasis (HR, 0.467; 95% CI, 0.271-0.806; p=0.006). JAG1(Mem) also showed a strong positive correlation with Notch1(Mem). In addition, tumors with JAG1(Mem) expression had more poorly encapsulated membranes (p=0.014). Furthermore, Notch1(Mem) expression correlated with HCC metastasis and was the strongest predictive factor for metastasis. However, in peri-tumoral tissues, most JAG1 (45/46) and Notch1 (41/46) was localized to the cytoplasm. The expression of OPN, one of the main targets of JAG1/Notch1 signaling and a crucial metastasis-related gene in HCC, correlated significantly with JAG1(Mem) expression. Knockdown of JAG1 expression or Notch1 expression induced the downregulation of OPN in HCC cells. Taken together, protein localization is a critical factor affecting the activity of the Notch cascade in the development of hepatocellular carcinoma. Furthermore, our results suggest that the JAG1/Notch1/OPN cascade represents a potential therapeutic target for hepatocellular carcinoma metastasis.
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Novel hybrids of metronidazole and quinolones: synthesis, bioactive evaluation, cytotoxicity, preliminary antimicrobial mechanism and effect of metal ions on their transportation by human serum albumin.
Eur J Med Chem
PUBLISHED: 08-24-2014
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A novel series of hybrids of metronidazole and quinolones as antimicrobial agents were designed and synthesized. Most prepared compounds exhibited good or even stronger antimicrobial activities in comparison with reference drugs. Furthermore, these highly active metronidazole-quinolone hybrids showed appropriate ranges of pKa, log P and aqueous solubility to pharmacokinetic behaviors and no obvious toxicity to A549 and human hepatocyte LO2 cells. Their competitive interactions with metal ions to HSA revealed that the participation of Mg(2+) ion in compound 7d-HSA association could result in a concentration increase of free compound 7d. Molecular modeling and experimental investigation of compound 7d with DNA suggested that possible antibacterial mechanism might be in relation with multiple binding sites between bioactive molecules and topo IV-DNA complex.
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Loss of PEG chain in routine SDS-PAGE analysis of PEG-maleimide modified protein.
Electrophoresis
PUBLISHED: 07-29-2014
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SDS-PAGE represents a quick and simple method for qualitative and quantitative analysis of protein and protein-containing conjugates, mostly pegylated proteins. PEG-maleimide (MAL) is frequently used to site-specifically pegylate therapeutic proteins via free cysteine residue by forming a thiosuccinimide structure for pursuing homogeneous products. The C-S linkage between protein and PEG-MAL is generally thought to be relatively stable. However, loss of intact PEG chain in routine SDS-PAGE analysis of PEG-maleimide modified protein was observed. It is a thiol-independent thioether cleavage and the shedding of PEG chain exclusively happens to PEG-MAL modified conjugates although PEG-vinylsulfone conjugates to thiol-containing proteins also through a C-S linkage. Cleavage kinetics of PEG40k-MAL modified ciliary neurotrophic factor showed this kind of degradation could immediately happen even in 1 min incubation at high temperature and could be detected at physiological temperature and pH, although the rate was relatively slow. This may provide another degradation route for maleimide-thiol conjugate irrespective of reactive thiol, although the specific mechanism is still not very clear for us. It would also offer a basis for accurate characterization of PEG-MAL modified protein/peptide by SDS-PAGE analysis.
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Changes in the adhesion and migration ability of peripheral blood cells: potential biomarkers indicating exposure dose.
Health Phys
PUBLISHED: 07-29-2014
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The expression of adhesion molecules and their related functions of adhesion and migration were investigated in peripheral blood mononuclear cells (PBMCs) to identify radiation-related changes and dose-dependency. The authors screened new biomarkers as radiation exposure dose indicators. Heparinized human peripheral blood was irradiated in vitro with different doses of ?-rays. The expression levels of the CD11a, CD11b, CD18, CD29, CD49d, and CD54 molecules on the surface of PBMC cells were determined by flow cytometry at different time points post-irradiation. The adhesion ability of human PBMCs was determined using an enzyme-linked immunoassay kit, and the migration ability of rat PBMCs was evaluated using a transwell chamber assay. Compared with the unirradiated control group, a significant increase (p < 0.05) in human CD11b/CD13 double-positive cells was detected 6 h post 6 Gy irradiation in vitro. These results indicated that the decrease in human CD29/CD13 double-positive cells in the 6 Gy exposure group at 6, 12, and 24 h post-irradiation was significant (p < 0.01). The adhesion ability of irradiated human PBMCs to IgG substrate increased significantly (p < 0.05) at 6 h after irradiation of 2, 4, or 6 Gy compared with non-irradiated controls. The migration ability of the rat PBMCs toward the MIP-1? chemokine significantly decreased (p < 0.05) with increasing irradiation doses. These results suggest that the protein expression of cell surface molecules and their associated cellular functions might be potential biomarkers for identifying radiation exposure doses in an emergency radiation accident.
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Effects of cryopreservation on human mesenchymal stem cells attached to different substrates.
J Tissue Eng Regen Med
PUBLISHED: 07-29-2014
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There is a need to preserve cell-seeded scaffolds or cell-matrix constructs for tissue-engineering and other applications. Cryopreservation is likely to be the most practical method. The aim of this study was to investigate how cryopreservation affects cells attached to different substrates and how they respond differently from those in suspension. Human mesenchymal stem cells (hMSCs) were studied for their close relevance to tissue-engineering and stem cell therapy applications, in particular how cryopreservation affects cell adherence, cell growth and the viability of hMSCs attached to different substrates, including glass, gelatin, matrigel and a matrigel sandwich. The effects of cryopreservation on F-actin organization, intracellular pH and mitochondrial localization of the adherent hMSCs were further investigated. It was found that cells attached to a glass surface could hardly survive the common cryopreservation protocol using 10% DMSO and a 1°C/min cooling rate. By contrast, cells attached to gelatin and matrigel could survive to a greater extent. Furthermore, cryopreservation affected the potential of cell attachment and proliferation, resulted in distortion of F-actin, led to alteration of intracellular pH of the hMSCs for all tested substrates and caused a change in the mitochondrial localization of hMSCs on a matrigel substrate and in a matrigel sandwich. Our results showed that cell attachment and cell viability could be improved by changing the interaction between cell and substrate through modification of the substrate properties, which has implications for scaffold design if cell-seeded scaffolds or engineered tissues need to be cryopreserved.
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Smoking, MATRICS consensus cognitive battery and P50 sensory gating in a Han Chinese population.
Drug Alcohol Depend
PUBLISHED: 07-21-2014
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The effects of smoking on cognitive performance have long been studied, with mixed results. P50 sensory gating has been used as endophenotype for studying nicotinic systems genetics, and P50 gating deficits have been reported to be a sensitive biomarker for cognitive impairment in schizophrenia. This study examined the inter-relationship between P50 suppression, cognitive function, and smoking in a healthy Han Chinese population, which has not been reported before.
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Rupestonic acids B-G, NO inhibitory sesquiterpenoids from Artemisia rupestris.
Bioorg. Med. Chem. Lett.
PUBLISHED: 07-10-2014
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Six new guaiane sesquiterpenoids, rupestonic acids B-G (1-6), have been isolated from the whole plants of Artemisia rupestris together with six known compounds (7-12). The structures of the new isolates (1-6) were elucidated on the basis of extensive 1D and 2D NMR analysis, and the absolute configurations were established by electronic circular dichroism (ECD) in combination with density functional theory calculations. In in vitro bioassays, compounds 2 and 6 exhibited significant inhibitory effects on LPS-stimulated NO production in BV-2 microglial cells with IC50 values of 2.6 and 2.2 ?M, respectively.
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nuMap: A Web Platform for Accurate Prediction of Nucleosome Positioning.
Genomics Proteomics Bioinformatics
PUBLISHED: 07-05-2014
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Nucleosome positioning is critical for gene expression and of major biological interest. The high cost of experimentally mapping nucleosomal arrangement signifies the need for computational approaches to predict nucleosome positions at high resolution. Here, we present a web-based application to fulfill this need by implementing two models, YR and W/S schemes, for the translational and rotational positioning of nucleosomes, respectively. Our methods are based on sequence-dependent anisotropic bending that dictates how DNA is wrapped around a histone octamer. This application allows users to specify a number of options such as schemes and parameters for threading calculation and provides multiple layout formats. The nuMap is implemented in Java/Perl/MySQL and is freely available for public use at http://numap.rit.edu. The user manual, implementation notes, description of the methodology and examples are available at the site.
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Symmetry breaking of ?-[H2W12O40](6-) depends on the transformation of isopolyoxotungstates.
Inorg Chem
PUBLISHED: 05-06-2014
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Two enantiotopic 1D chain compounds, [Cu3(L1)3(H2O)2(H2W12O40)]·4H2O (1a,b; L1 = 2-(4,6-bis(pyridin-2-yl)pyridin-2-yl)pyridine), crystallizing in the chiral space group P212121 were prepared and spontaneously resolved in the absence of any chiral source. Interestingly, compounds 1a,b can be prepared from a [W7O24](6-) aqueous solution, [(n-C4H9)4N]4[W10O32], or Na10[H2W12O42], but when [H2W12O40](6-) aqueous solution was the starting material, the achiral compound [CuL1]2[H4W12O40]·5H2O (2) was obtained. When a terpyridine ligand (L2) having a coordination mode similar to that of L1 was used, the mesomeric dimer [Cu3(L2)3(H2O)(H2W12O40)]2·4H2O (3) was obtained from [W7O24](6-) aqueous solution or Na10[H2W12O42], but from [H2W12O40](6-) aqueous solution only compound [Cu2(L2)2Cl2]2[W10O32] (4) was isolated. It is notable that in compounds 1a,b and 3 the symmetry of the ?-[H2W12O40](6-) cluster is broken by asymmetric coordination with metal-organic units in a similar mode. As the asymmetric subunit based on a tridecorated [H2W12O40](6-) cluster can be obtained from several isopolyoxotungstate sources except for [H2W12O40](6-), we speculate that the symmetry breaking of ?-[H2W12O40](6-) depends on the transformation of isopolyoxotungstates. Furthermore, during the transformation a possible reaction intermediate as the precursor for 1a,b, compound [Cu3(L1)3(H2O)3(H4W11O38)] (5), has been presented and characterized by density functional theory (DFT) calculations.
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Anoxic stress and rapid cold hardening enhance cold tolerance of the migratory locust.
Cryobiology
PUBLISHED: 05-02-2014
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Anoxia and rapid cold hardening (RCH) can increase the cold tolerance of many animals. However, mechanisms underlying these two kinds of stresses remain unclear. In this study, we aimed to explore the relationship of acclimation to cold stress with acclimation to anoxic stress in the migratory locust, Locusta migratoria. RCH at 0°C for 3h promoted the survival of cold stress-exposed locusts. Anoxic hypercapnia (CO2 anoxic treatment) for 40 min exerted an effect similar to that of RCH. Anoxic hypercapnia within 1h can all promote the cold hardiness of locusts. We investigated the transcript levels of six heat shock protein (Hsp) genes, namely, Hsp20.5, Hsp20.6, Hsp20.7, Hsp40, Hsp70, and Hsp90. Four genes, namely, Hsp90, Hsp40, Hsp20.5, and Hsp20.7, showed differential responses to RCH and anoxic hypercapnia treatments. Under cold stress, locusts exposed to the two regimens showed different responses for Hsp90, Hsp20.5, and Hsp20.7. However, the varied responses disappeared after recovery from cold stress. Compared with the control group, the transcript levels of six Hsp genes were generally downregulated in locusts subjected to anoxic hypercapnia or/and RCH. These results indicate that anoxic stress and RCH have different mechanisms of regulating the transcription of Hsp family members even if the two treatments exerted similar effects on cold tolerance of the migratory locust. However, Hsps may not play a major role in the promotion of cold hardiness by the two treatments.
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Molecular cloning and characterization of NPR1 gene from Arachis hypogaea.
Mol. Biol. Rep.
PUBLISHED: 05-02-2014
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The NPR1 gene was an important regulator for a plant disease resistance. The cDNA of NPR1 gene was cloned from peanut cultivar Ri Hua 1 by rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The full length cDNA of Arachis hypogaea NPR1 consisted of 2,078 base pairs with a 1,446 bp open-reading frame encoding 481 amino acids. The predicted NPR1 contained the highly conserved functional domains (BTB/POZ domain from M1 to D116), protein-protein interaction domains (three ankyrin repeats from K158 to L186; N187 to L217 and R221 to D250) and one NPR1-like domain (C262 to S469). The DNA sequence of the NPR1 gene was 2,332 or 2,223 bp. Both two sequences contained three introns and four exons. The NPR1 transcripts were expressed mainly in roots and leaves, while fewer signals were detected in the stems. Amount of the NPR1 transcript was significantly increased 1 h after salicylic acid challenge and was eventually 5.3 times greater than that in the control group. Both the DNA sequence and the coding sequence were obtained from eight cultivars and nine wild species of Arachis. Maximum likelihood analyses of d N/d S ratios for 25 sequences from different species showed that different selection pressures may have acted on different branches.
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CXCR7 correlates with the differentiation of hepatocellular carcinoma and suppresses HNF4? expression through the ERK pathway.
Oncol. Rep.
PUBLISHED: 04-16-2014
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Hepatocellular carcinoma (HCC) is a malignancy with dysregulated differentiation. However, effective differentiation therapy for HCC is lacking. Previous evidence suggests that CXCR7 is associated with the differentiation of embryonic stem cells. Here, we evaluated the potential role of CXCR7 in the differentiation of HCC. In HCC cell lines, the expression of cancer stem cell-related markers was assessed by flow cytometry and confirmed by western blot and immunofluorescence analyses. Dimethyl sulfoxide, oncostatin M and dexamethasone were used to induce the differentiation of HCC. Immunohistochemical assay was performed on a tissue microarray based on 112 HCC cases that received hepatectomy. Ligand activation, inhibition assays and RNA interference were used to analyze the regulation of hepatocyte nuclear factor 4? (HNF4?) by the CXCR7 pathway. Huh7 and HCCLM3 cell lines were screened for differentiation induction based on biomarkers of hepatic cancer stem cells. CXCR7 was found to be closely associated with the differentiation of HCC, and an inverse expression trend between CXCR7 and HNF4? was found upon induced differentiation. Clinically, high CXCR7 expression was negatively correlated with HNF4? expression in patients with relatively well-differentiated HCC. Moreover, high CXCR7 expression was correlated with poor overall survival and accelerated post-resection metastasis in HCC with a low HNF4? level. Mechanistically, CXCR7 signaling inhibited HNF4? through extracellular regulated protein kinase (ERK) activation, which was inhibited by U0126, an inhibitor of MAPK/ERK kinases 1 and 2. Knockdown of CXCR7 further confirmed that CXCR7 signaling can regulate HNF4? expression. Taken together, our findings indicate that CXCR7 participates in the differentiation of HCC by regulating HNF4?. The CXCR7-ERK-HNF4? cascade represents a new target for the differentiation therapy of HCC.
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Rapid discrimination of the geographical origins of an oolong tea (anxi-tieguanyin) by near-infrared spectroscopy and partial least squares discriminant analysis.
J Anal Methods Chem
PUBLISHED: 04-13-2014
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This paper focuses on a rapid and nondestructive way to discriminate the geographical origin of Anxi-Tieguanyin tea by near-infrared (NIR) spectroscopy and chemometrics. 450 representative samples were collected from Anxi County, the original producing area of Tieguanyin tea, and another 120 Tieguanyin samples with similar appearance were collected from unprotected producing areas in China. All these samples were measured by NIR. The Stahel-Donoho estimates (SDE) outlyingness diagnosis was used to remove the outliers. Partial least squares discriminant analysis (PLSDA) was performed to develop a classification model and predict the authenticity of unknown objects. To improve the sensitivity and specificity of classification, the raw data was preprocessed to reduce unwanted spectral variations by standard normal variate (SNV) transformation, taking second-order derivatives (D2) spectra, and smoothing. As the best model, the sensitivity and specificity reached 0.931 and 1.000 with SNV spectra. Combination of NIR spectrometry and statistical model selection can provide an effective and rapid method to discriminate the geographical producing area of Anxi-Tieguanyin.
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Prediction of nucleosome rotational positioning in yeast and human genomes based on sequence-dependent DNA anisotropy.
BMC Bioinformatics
PUBLISHED: 03-31-2014
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An organism's DNA sequence is one of the key factors guiding the positioning of nucleosomes within a cell's nucleus. Sequence-dependent bending anisotropy dictates how DNA is wrapped around a histone octamer. One of the best established sequence patterns consistent with this anisotropy is the periodic occurrence of AT-containing dinucleotides (WW) and GC-containing dinucleotides (SS) in the nucleosomal locations where DNA is bent in the minor and major grooves, respectively. Although this simple pattern has been observed in nucleosomes across eukaryotic genomes, its use for prediction of nucleosome positioning was not systematically tested.
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Activation of STAT5 contributes to proliferation in U87 human glioblastoma multiforme cells.
Mol Med Rep
PUBLISHED: 03-25-2014
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Rapid increases in the tyrosine phosphorylation of signal transducers and activators of transcription 5 (STAT5) proteins have been extensively documented in cells stimulated with cytokines and growth factors. However, the mechanisms by which STAT5 translocates to the nucleus and regulates proliferation in human glioblastoma multiforme cells have not been studied in detail. To the best of our knowledge, the present study demonstrated for first time that stimulation of a glioblastoma multiforme (GBM) cell line (U87-MG) with hepatocyte growth factor (HGF) resulted in the phosphorylation of STAT5 at Tyr-694/699 and nuclear translocation of STAT5. In addition, HGF promoted nuclear translocation of STAT5 in a time-dependent manner and increased the proliferation of U87-MG cells. In order to determine the role of STAT5 directly, RNA interference was used to knockdown STAT5 expression in the U87-MG cell line. It was illustrated that small interfering RNA (siRNA) against STAT5 successfully inhibited the protein expression of STAT5 in the U87-MG cell line, leading to a potent suppression of tumor cell proliferation with or without HGF treatment. In order to broaden the investigation and to determine the role of STAT5 in vivo, immunohistochemistry (IHC) was applied to evaluate STAT5 expression in 100 newly diagnosed glioma and 10 non-neoplastic brain tissues. p-STAT5 expression increased according to the histopathological grade of the glioma. However, no p-STAT5 staining was observed in non-neoplastic brain tissues. These findings suggested that inhibition of the STAT5 pathway may be an effective therapeutic strategy for the clinical management of GBM.
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MiR-612 suppresses the stemness of liver cancer via Wnt/?-catenin signaling.
Biochem. Biophys. Res. Commun.
PUBLISHED: 03-20-2014
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Previous research showed that microRNA-612 (miR-612) has inhibitory effects on cell proliferation, migration, invasion, and metastasis of hepatocellular carcinoma (HCC). AKT2 was confirmed to be a direct target of miR-612, through which the epithelial-mesenchymal transition (EMT) and metastasis of HCC were inhibited. Our present findings reveal that miR-612 is able to suppress the stemness of HCC by reducing the number and size of tumorspheres as well as clone formation in soft agar, and to relieve drug resistance to cisplatin and 5-fluorouracil. In addition, miR-612 hampered the capacity of tumorigenesis in NOD/SCID mice and redistributed the tumor invasive frontier of miR-612-modulating cells. Finally, our findings suggest that Wnt/?-catenin signaling is required in the regulation of EMT-associated stem cell-like traits by miR-612.
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Arabidopsis RAV1 transcription factor, phosphorylated by SnRK2 kinases, regulates the expression of ABI3, ABI4, and ABI5 during seed germination and early seedling development.
Plant J.
PUBLISHED: 03-19-2014
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The phytohormone abscisic acid (ABA) modulates a number of processes during plant growth and development. In this study, the molecular mechanism of Arabidopsis RAV (Related to ABI3/VP1) transcription factor RAV1 involving ABA signaling was investigated. RAV1-underexpressing lines were more sensitive to ABA than wild-type plants during seed germination and early seedling development, whereas RAV1-overexpressing lines showed strong ABA-insensitive phenotypes. Overexpression of RAV1 repressed ABI3, ABI4, and ABI5 expression, and RAV1 bound to the ABI3, ABI4, and ABI5 promoters in vitro and in vivo, indicating that RAV1 directly down-regulates the expression of ABI3, ABI4, and ABI5. The interruption of ABI5 function in RAV1-U abi5 plants abolished the ABA-hypersensitive phenotype of RAV1-U plants, demonstrating that ABI5 is epistatic to RAV1. RAV1 interacted with SNF1-RELATED PROTEIN KINASE SnRK2.2, SnRK2.3 and SnRK2.6 in the nucleus. In vitro kinase assays showed that SnRK2.2, SnRK2.3 and SnRK2.6 phosphorylated RAV1. Transient expression assays revealed that SnRK2.2, SnRK2.3 and SnRK2.6 reduced the RAV1-dependent repression of ABI5, and the ABA-insensitive phenotype of the RAV1-overexpressing line was impaired by overexpression of SnRK2.3 in the RAV1 OE3 plants. Together, these results demonstrated that the Arabidopsis RAV1 transcription factor plays an important role in ABA signaling by modulating the expression of ABI3, ABI4, and ABI5, and that its activity is negatively affected by SnRK2s.
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Pattern of genetic variation of yellow catfish Pelteobagrus fulvidraco Richardso in Huaihe river and the Yangtze river revealed using mitochondrial DNA control region sequences.
Mol. Biol. Rep.
PUBLISHED: 02-08-2014
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Genetic variability and population genetic structure of the yellow catfish Pelteobagrus fulvidraco Richardso in the Huaihe river and the Yangtze river was examined with a 810-bp of the mitochondrial DNA control region. A total of 70 haplotypes were identified from 145 samples, which were characterized with high haplotype diversity (h = 0.9832 ± 0.0041) but low nucleotide diversity (? = 0.0415 ± 0.0201). The analysis of molecular variance and phylogenetic reconstructions detected significant geographic structure between Huaihe river and Yangtze with FST = 0.1183 (P = 0.0000). Neighbor-joining (NJ) phylogenetic analyses identified two distinct clades (bootstrap support 99 %). The medium joining network drawn using the complete data set was reticulated and also distinctly split the 70 haplotypes into two groups corresponding to those of the NJ tree. Departures from neutrality were not significant for the Huaihe river and the Yangtze river Pelteobagrus fulvidraco, concordant with the observed multimodal mismatch distributions (P > 0.05), which suggested that the effective size of this species has been large and stable for a long period. The question about the existence of significant genetic differentiation for Pelteobagrus fulvidraco in the Yangtze river and Huaihe river basins remains to be further studied with molecular nuclear markers and larger sample sizes from throughout the river basins.
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Characterization of an aphid-specific, cysteine-rich protein enriched in salivary glands.
Biophys. Chem.
PUBLISHED: 02-05-2014
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Aphids secrete saliva into the phloem during their infestation of plants. Previous studies have identified numerous saliva proteins, but little is known about the characteristics (physical and chemical) and functions of these proteins in aphid-plant interactions. This study characterized an unknown protein (ACYPI39568) that was predicted to be enriched in the salivary glands of pea aphid. This protein belongs to an aphid-specific, cysteine-rich protein family that contains 14 conserved cysteines. ACYPI39568 is a monomeric globular protein with a high beta strand extent. The binding stoichiometric ratios for Zn(2+) and ACYPI39568 were approximately 3:1 and 1:1 at two binding sites. ACYPI39568 was predominantly expressed in the first instar stage and in the salivary glands. Aphids required more ACYPI39568 when feeding on plants than when feeding on an artificial diet. However, the interference of ACYPI39568 expression did not affect the survival rate of aphids on plants.
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An electrochemical DNA sensor for sequence-specific DNA recognization in a homogeneous solution.
Biosens Bioelectron
PUBLISHED: 02-01-2014
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In this work, a sensitive electrochemical DNA sensor based on an avidin modified electrode and a DNA-functionalized Au nanoparticle (DFNP) was developed. The DNA-functionalized Au nanoparticle contained two kinds of DNA, one is hairpin probe DNA with a biotin at the 3' terminal and a thiol at the 5' terminal, the other is methylene blue (MB)-labeled linear signal DNA. Without hybridizing with the target DNA, the loop of the hairpin impeded biotin linked with avidin on electrode. However, after target hybridization, the hairpin was opened and biotin was recognized by avidin which resulted in a DNA-functionalized Au nanoparticle brought on the electrode surface. Electrochemical signals of MB bound to signal DNA were measured by differential pulse voltammetry (DPV). Taking advantage of amplification effects of the AuNP and binding specificity of the hairpin probe, this DNA biosensor greatly simplified the electrochemical DNA detection method and displayed high specificity in DNA detection. By using this new method, we demonstrate that this prototype sensor has been able to detect as low as picomolar DNA targets with excellent differentiation ability even for a single mismatch.
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Overexpression of the receptor-like protein kinase genes AtRPK1 and OsRPK1 reduces the salt tolerance of Arabidopsis thaliana.
Plant Sci.
PUBLISHED: 01-29-2014
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AtRPK1 (AT1G69270) is a leucine-rich repeat receptor-like protein kinase (LRR-RLK) gene in Arabidopsis thaliana. The rice gene Os07g0602700 (OsRPK1) is the homolog of AtRPK1. AtRPK1 and OsRPK1 were overexpressed and the expression of AtRPK1 was inhibited by RNAi in A. thaliana. The functional results showed that the degrees of salt tolerance of the 35S:RPK1 A. thaliana plants were significantly lower than that of the control plants. The AtRPK1-RNAi A. thaliana plants exhibited higher salt tolerance than the wild-type plants (Col). The subcellular localisation results showed that the RPK1 proteins were mainly distributed on the cell membrane and that the overexpressed AtRPK1 proteins exhibited a significantly clustered distribution. The physiological analyses revealed that the overexpression of the RPK1 genes increased the membrane permeability in the transgenic A. thaliana plants. In response to salt stress, these plants exhibited an increased Na(+) flux into the cell, which caused greater damage to the cell. The real-time quantitative PCR analysis showed that the expression of the P5CS1 gene was inhibited and the SOS signalling pathway was blocked in the 35S:AtRPK1 A. thaliana plants. These effects at least partially contribute to the salt-sensitive phenotype of the 35S:RPK1 plants.
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Synthesis and bioactive evaluation of a novel series of coumarinazoles.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-24-2014
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A series of novel coumarinazoles were designed, synthesized, and characterized by IR, NMR, MS and HRMS spectra. The bioactive assay for the newly prepared compounds against six bacteria and five fungi manifested that most new compounds exhibited good or even stronger antibacterial and antifungal activities in comparison with reference drugs Chloromycin, Norfloxacin and Fluconazole. Bis-azole alcohols 7a and 7d-e showed better anti-Candida utilis activity than mono-azole derivatives 4a and 4d-e at the tested concentrations, and they were more potent than the clinical Fluconazole. While triazole alcohol 7a gave comparable anti-Candida albicans and anti-Candida mycoderma activity to Fluconazole and better anti-MRSA activity than mono-triazole one 4a and clinical Norfloxacin. 1H-Benzoimidazol-2-ylthio coumarin derivatives 4e and 7e gave the strongest anti-Escherichia coli JM109 efficacy. Oxiran-2-ylmethoxy moiety was found to be a beneficial fragment to improve antibacterial and antifungal activity to some extent.
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Over-transcription of genes in a parathion-resistant strain of mosquito Culex pipiens quinquefasciatus.
Insect Sci.
PUBLISHED: 01-17-2014
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Insecticide resistance is an evolutionary adaptation that develops quite quickly in mosquitoes because of the high selection pressure of chemical insecticides, rapid generation time and large population size. Identification of genes associated with insecticide resistance is fundamental to understand the complex processes responsible for resistance. We compared the gene transcriptional profiles of parathion-resistant and -susceptible Culex pipiens quinquefasciatus using a combination of suppression subtractive hybridization and complementary DNA (cDNA) microarray techniques. A total of 278 colonies were selected from the resistant-susceptible mosquito subtractive library, 38 of which showed more than two fold stronger immunoblotting signals in the resistant strain than in the susceptible strain using cDNA microarray selection. The sequencing results showed that the 38 colonies can be matched to 12 genes of C. p. quinquefasciatus. Eight genes were confirmed to be overexpressed by more than two fold in the resistant strain. These genes encode chymotrypsin-1, theta glutathione S-transferase, lipase 3, larval serum protein 1 ? chain, cytochrome b, mitochondrial ribosomal large subunit, 28S rRNA, and a protein with unknown function. This study serves as a preliminary attempt to identify new genes associated with organophosphate resistance in this mosquito species and provides insights into the complicated physiological phenomenon of insecticide resistance.
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The locust genome provides insight into swarm formation and long-distance flight.
Nat Commun
PUBLISHED: 01-16-2014
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Locusts are one of the world's most destructive agricultural pests and represent a useful model system in entomology. Here we present a draft 6.5?Gb genome sequence of Locusta migratoria, which is the largest animal genome sequenced so far. Our findings indicate that the large genome size of L. migratoria is likely to be because of transposable element proliferation combined with slow rates of loss for these elements. Methylome and transcriptome analyses reveal complex regulatory mechanisms involved in microtubule dynamic-mediated synapse plasticity during phase change. We find significant expansion of gene families associated with energy consumption and detoxification, consistent with long-distance flight capacity and phytophagy. We report hundreds of potential insecticide target genes, including cys-loop ligand-gated ion channels, G-protein-coupled receptors and lethal genes. The L. migratoria genome sequence offers new insights into the biology and sustainable management of this pest species, and will promote its wide use as a model system.
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MiR-34a regulates apoptosis in liver cells by targeting the KLF4 gene.
Cell. Mol. Biol. Lett.
PUBLISHED: 01-10-2014
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MicroRNAs (miRNAs) regulate gene expression by inhibiting translation or targeting messenger RNA (mRNA) for degradation in a posttranscriptional fashion. In this study, we show that ectopic expression of miR-34a-5p reduces the mRNA and protein levels of Krüppel-like factor 4 (KLF4). We also demonstrate that miR-34a targets the 3'-untranslated mRNA region of KLF4 and show that overexpression of miR-34a induces a significant level of apoptosis in BNL CL.2 cells exposed to doxorubicin or 10 Gy X-ray. Our data suggest that the effects of miR-34a on apoptosis occur due to the downregulation of KLF4.
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Sex-Determination Gene SRY Potentially Associates with Poor Prognosis but Not Sex Bias in Hepatocellular Carcinoma.
Dig. Dis. Sci.
PUBLISHED: 01-08-2014
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Gender disparity is well known in hepatocellular carcinoma (HCC). SRY is a critical sex-determination gene involved in embryonic development.
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Comparison of HPV genotypes and viral load between different sites of genital tract: the significance for cervical cancer screening.
Cancer Epidemiol
PUBLISHED: 01-04-2014
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To compare the consistency of HPV genotype and viral loads among different sites within the female genital tract, and to correlate these with clinical outcomes.
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Goosecoid promotes the metastasis of hepatocellular carcinoma by modulating the epithelial-mesenchymal transition.
PLoS ONE
PUBLISHED: 01-01-2014
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The homeobox gene, goosecoid (GSC), is a transcription factor that participates in cell migration during embryonic development. Because cell migration during development has characteristics similar to cell invasion during metastasis, we evaluated the potential role of GSC in the metastasis of hepatocellular carcinoma (HCC). GSC expression in HCC cell lines and tissues was evaluated, and its effects on the migration potential of HCC cells were determined by GSC knock-down and overexpression methods. In addition, the prognostic role of GSC expression in the metastasis of cancer cells in HCC patients was determined. Our data showed that GSC was highly expressed in several HCC cell lines, particularly in a highly metastatic HCC cell line. Overexpression of GSC promoted cell migration and invasion of HCC cells in vitro. Gain-of-function induced the epithelial-mesenchymal transition but not collective cell migration, whereas loss-of-function induced the reverse change. High-level expression of GSC correlated closely with poor survival and lung metastasis in HCC patients; lung metastases showed more upregulated GSC expression than the primary tumor. We conclude that GSC promotes metastasis of HCC potentially through initiating the epithelial-mesenchymal transition. GSC is also a prognostic factor for poor survival and metastasis of HCC, which suggests its potential as a therapeutic target for metastatic HCC.
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Identification and characterization of microRNAs in normal equine tissues by Next Generation Sequencing.
PLoS ONE
PUBLISHED: 01-01-2014
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The role of microRNAs (miRNAs) as a post-transcriptional gene regulator has been elucidated in a broad range of organisms including domestic animals. Characterization of miRNAs in normal tissues is an important step to investigate the functions of miRNAs in various physiological and pathological conditions. Using Illumina Next Generation Sequencing (NGS) technology, we identified a total of 292 known and 329 novel miRNAs in normal horse tissues including skeletal muscle, colon and liver. Distinct sets of miRNAs were differentially expressed in a tissue-specific manner. The miRNA genes were distributed across all the chromosomes except chromosomes 29 and 31 in the horse reference genome. In some chromosomes, multiple miRNAs were clustered and considered to be polycistronic transcript. A base composition analysis showed that equine miRNAs had a higher frequency of A+U than G+C. Furthermore, U tended to be more frequent at the 5' end of miRNA sequences. This is the first experimental study that identifies and characterizes the global miRNA expression profile in normal horse tissues. The present study enriches the horse miRNA database and provides useful information for further research dissecting biological functions of miRNAs in horse.
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Dynamic expression patterns of differential proteins during early invasion of hepatocellular carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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Tumor cell invasion into the surrounding matrix has been well documented as an early event of metastasis occurrence. However, the dynamic expression patterns of proteins during early invasion of hepatocellular carcinoma (HCC) are largely unknown. Using a three-dimensional HCC invasion culture model established previously, we investigated the dynamic expression patterns of identified proteins during early invasion of HCC.
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Severe fever with thrombocytopenia syndrome, Shandong Province, China, 2011.
Emerging Infect. Dis.
PUBLISHED: 01-01-2014
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Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease in China. The incidence and clinical and laboratory characteristics of SFTS are not clearly defined. During May 22-October 2, 2011, a total of 24 patients with fever, thrombocytopenia, and leukopenia were clinically diagnosed as having SFTS in Yiyuan County, Shandong Province, China. We conducted laboratory tests for these SFTS patients. SFTS virus (SFTSV) infection was confirmed in 22 patients by using reverse transcription PCR and ELISA by acute-phase and convalescent-phase serum samples. Clinical and laboratory manifestations included fever (100%), gastrointestinal symptoms (91%), myalgia (55%), chills (41%), thrombocytopenia (100%), and leukopenia (95%).
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[Analysis of malaria endemic situation in Shanxian County from 2002 to 2011].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 12-24-2013
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To analyze the endemic situation of malaria in Shanxian County, Shandong Province, China in the last 10 years, so as to understand the epidemiological characteristics of the disease and provide the evidence for the establishment of control strategy to eliminate malaria.
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[Budd-Chiari syndrome in children and adolescents: therapeutic radiological intervention].
Zhonghua Er Ke Za Zhi
PUBLISHED: 11-15-2013
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Due to its minimal-invasive approach, endovascular procedure had replaced surgery in treating Budd-Chiari syndrome (BCS). The interventional therapy was a safe and effective treatment in adults with BCS and the cure rate was high. However Budd-Chiari syndrome in children and adolescents is rare. Published literature on interventional procedure for Budd-Chiari syndrome in children and adolescents is scarce. The aim of the study was to present results of percutaneous transluminal angioplasty (PTA) and stents placement in children and adolescents with BCS and to evaluate the efficacy and safety in these patients of this approach.
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Rotational positioning of nucleosomes facilitates selective binding of p53 to response elements associated with cell cycle arrest.
Nucleic Acids Res.
PUBLISHED: 10-22-2013
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The tumor suppressor protein p53 exhibits high affinity to the response elements regulating cell cycle arrest genes (CCA-sites), but relatively low affinity to the sites associated with apoptosis (Apo-sites). This in vivo tendency cannot be explained solely by the p53-DNA binding constants measured in vitro. Since p53 can bind nucleosomal DNA, we sought to understand if the two groups of p53 sites differ in their accessibility when embedded in nucleosomes. To this aim, we analyzed the sequence-dependent bending anisotropy of human genomic DNA containing p53 sites. For the 20 CCA-sites, we calculated rotational positioning patterns predicting that most of the sites are exposed on the nucleosomal surface. This is consistent with experimentally observed positioning of human nucleosomes. Remarkably, the sequence-dependent DNA anisotropy of both the p53 sites and flanking DNA work in concert producing strong positioning signals. By contrast, both the predicted and observed rotational settings of the 38 Apo-sites in nucleosomes suggest that many of these sites are buried inside, thus preventing immediate p53 recognition and delaying gene induction. The distinct chromatin organization of the CCA response elements appears to be one of the key factors facilitating p53-DNA binding and subsequent activation of genes associated with cell cycle arrest.
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Fabrication and characterization of Ag film with sub-nanometer surface roughness as a flexible cathode for inverted top-emitting organic light-emitting devices.
Nanoscale
PUBLISHED: 09-23-2013
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An ultra-smooth Ag film with sub-nanometer surface roughness on a flexible substrate has been fabricated by a template-stripping process and its effect on the carrier injection and transport in organic light-emitting devices (OLEDs) has been investigated. The use of the ultra-smooth Ag film as an electrode results in both enhanced carried injection due to the improved contact between the electrode and the organic layer and enhanced carrier transport due to the larger grain size of the deposited organic layer on it. The ultra-smooth Ag film on the flexible substrate has been applied in inverted top-emitting OLEDs (ITOLEDs) as cathode, which exhibit improved efficiency due to the enhanced electron injection and transport. The maximum current efficiency of the ITOLEDs on the flexible substrate is 9.72 cd A(-1), whereas it is 6.03 cd A(-1) for the devices on the conventional Si substrate, which corresponds to about a 62% enhancement. Moreover, the flexible ITOLEDs keep their good performance under a small bending radius and after repeated bending.
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[Association between serum calcium levels and the risk of liver cirrhosis].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 09-11-2013
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To examine the association between serum calcium levels and the risk of liver cirrhosis.
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[Chemical constituents from ethyl acetate extract of Artemisia rupestris].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-10-2013
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Chemical constituents of ethyl acetate extract of Artemisia rupestris were isolated and purified by various chromatographic methods, including silica gel, ODS and Sephadex LH-20. Their structures were elucidated on the basis of spectroscopic data analysis. 12 compounds were separated from A. rupestris and their structures were identified as 5,4-dihydroxy -3,6,7-trimethoxy flavone (1), R-(-) -vestitol (2), tricin (3), chrysoeriol (4), 3-indole carboxylic acid (5), esculetin (6), apigenin (7), luteolin (8), trans-caffeic acid (9), casticin (10), chrysosptertin B (11) and artemetin (12). Compound 2 was obtained from the genus Artemisia for the first time, and compounds 1-6 and 9 were separated from this plant for the first time.
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[Prospective study on the relation between serum vitamin D levels and liver cirrhosis risk].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 08-24-2013
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To explore the relation between serum vitamin D (25(OH)D) concentrations and liver cirrhosis. Methods A nested case control study was designed based on the Nutrition Intervention Trial (NIT) cohort, from which non-degraded serum samples and complete baseline and follow-up data were available for 282 individuals diagnosed with liver cirrhosis and 564 healthy controls. The serum samples were tested by enzyme-linked immunosorbent assay to detect and quantify 25(OH)D, as well as hepatitis B virus surface antigen and core antibody and hepatitis C virus antibody. The study participants were divided into four groups according to quartile range of 25(OH)D concentration and logistic regression modeling was used to evaluate the relation with liver cirrhosis risk by estimating odds ratios (ORs) and 95% confidence intervals (CIs).
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[Bioavailability of dissolved organic nitrogen components in the lake sediment to alage].
Huan Jing Ke Xue
PUBLISHED: 08-17-2013
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Samples in the sediments of Wuliangsuhai and Erhai Lake were selected, and the technologies of XAD-8 resins separation and three dimensional fluorescence excitation-emission matrix (3DEEM) spectra were applied, in order to study the bioavailability of dissolved organic nitrogen components to alage under the room cultivation. The obtained results showed that: (1) Average loss of DON and DOC from sediments was below 5% after dividing DON into different groups, which means the technology of XAD- 8 resins separation could be used in the study of DON components in the lake sediment. (2) Through 3DEEM analysis, hydrophilic and hydrophobic DON was dominated by protein-like and humic-like materials in the lake sediment, respectively. (3) Under the hydrophilic component condition, growth curves of algae tended to show an "S" shape with a straight upward trend in the sediments of Wuliangsuhai and Erhai lake,with the maximum algal density reaching 535.5 x 10(4) and 709.5 x 10(4) per milliliter, respectively. Meanwhile, the DON concentrations were significantly reduced after cultivation to 2.46 and 2.98 mg x L(-1), respectively, which suggests that hydrophilic DON in the lake sediment was the bioavailable organic nitrogen for alage. (4) Under the hydrophbic component conditions, growth curves of algae tended to show a "unimodal" shape in the sediments of Wuliangsuhai and Erhai lake,with the maximum algal density reaching 113.5 x 10(4) and 275.5 x 10(4) per milliliter,respectively. The DON concentrations were significantly reduced during the early cultivation period, and then kept stable in the late period, which suggests that the hydrophobic DON component bioavailable to alage was low in short-term, and the hydrophobic DON component had hardly any positive effect on the growth of algae.
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Ultrasound-assisted lipase-catalyzed synthesis of D-isoascorbyl palmitate: process optimization and Kinetic evaluation.
Chem Cent J
PUBLISHED: 08-09-2013
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D-isoascorbic acid is a food antioxidant additive and used in accordance with Good Manufacturing Practice (GMP). High solubility in water (about 150 g/L at 25°C) reduces its effectiveness in stabilizing fats and oils. Our research group had successfully synthesized D-isoascorbyl palmitate using immobilized lipase Novozym 435 as a biocatalyst. Low production efficiency of D-isoascorbyl palmitate is still a problem for industrial production due to the long reaction time of over 24 h. In the present work, ultrasonic treatment was applied for accelerating the reaction process. The operation parameters were optimized to obtain the maximum D-isoascorbyl palmitate conversion rate by using a 5-level-4-factor Central Composite Design (CCD) and Response Surface Methdology (RSM). The reaction apparent kinetic parameters under the ultrasound treatment and mechanical shaking conditions were also determined and compared.
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Hydrogen peroxide promotes epithelial to mesenchymal transition and stemness in human malignant mesothelioma cells.
Asian Pac. J. Cancer Prev.
PUBLISHED: 07-27-2013
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Reactive oxygen species (ROS) are known to promote mesothelial carcinogenesis that is closely associated with asbestos fibers and inflammation. Epithelial to mesenchymal cell transition (EMT) is an important process involved in the progression of tumors, providing cancer cells with aggressiveness. The present study was performed to determine if EMT is induced by H2O2 in human malignant mesothelioma (HMM) cells. Cultured HMM cells were treated with H2O2, followed by measuring expression levels of EMT-related genes and proteins. Immunohistochemically, TWIST1 expression was confined to sarcomatous cells in HMM tissues, but not in epithelioid cells. Treatment of HMM cells with H2O2 promoted EMT, as indicated by increased expression levels of vimentin, SLUG and TWIST1, and decreased E-cadherin expression. Expression of stemness genes such as OCT4, SOX2 and NANOG was also significantly increased by treatment of HMM cells with H2O2. Alteration of these genes was mediated via activation of hypoxia inducible factor 1 alpha (HIF-1?) and transforming growth factor beta 1 (TGF-?1). Considering that treatment with H2O2 results in excess ROS, the present study suggests that oxidative stress may play a critical role in HMM carcinogenesis by promoting EMT processes and enhancing the expression of stemness genes.
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[Impacts of electroacupuncture at Lingtai (GV 10) and Shendao (GV 11) on premature heartbeat].
Zhongguo Zhen Jiu
PUBLISHED: 07-27-2013
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To observe the specific clinical efficacy of electroacupuncture at Lingtai (GV 10) and Shendao (GV 11) on premature heartbeat.
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[Breast cancer subtypes based on ER/PR and Her2 expression: comparison of mr imaging features].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 07-18-2013
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To evaluate the magnetic resonance (MR) imaging findings of breast cancer subtypes based on the profiles of ER/PR and Her2.
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Vascular endothelial cells facilitated HCC invasion and metastasis through the Akt and NF-?B pathways induced by paracrine cytokines.
J. Exp. Clin. Cancer Res.
PUBLISHED: 06-24-2013
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It is well documented that cancer cells secrete angiogenic factors to recruit and sustain tumor vascular networks. However, little is known about the effects of endothelial cells on the behavior of tumor cells. The study here was to determine the roles of endothelial cells in HCC cell growth, migration and invasion.
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Human papillomavirus genotype distribution in cervical intraepithelial neoplasia grades 1 or worse among 4215 Chinese women in a population-based study.
Cancer Epidemiol
PUBLISHED: 06-16-2013
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To estimate the burden of human papillomavirus (HPV) infection and cervical disease among sexually active women in a sample of Chinese women.
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Visual scanning of emotional faces in schizophrenia.
Neurosci. Lett.
PUBLISHED: 05-27-2013
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This study investigated eye movement differences during facial emotion recognition between 101 patients with chronic schizophrenia and 101 controls. Independent of facial emotion, patients with schizophrenia processed facial information inefficiently; they showed significantly more direct fixations that lasted longer to interest areas (IAs), such as the eyes, nose, mouth, and nasion. The total fixation number, mean fixation duration, and total fixation duration were significantly increased in schizophrenia. Additionally, the number of fixations per second to IAs (IA fixation number/s) was significantly lower in schizophrenia. However, no differences were found between the two groups in the proportion of number of fixations to IAs or total fixation number (IA fixation number %). Interestingly, the negative symptoms of patients with schizophrenia negatively correlated with IA fixation number %. Both groups showed significantly greater attention to positive faces. Compared to controls, patients with schizophrenia exhibited significantly more fixations directed to IAs, a higher total fixation number, and lower IA fixation number/s for negative faces. These results indicate that facial processing efficiency is significantly decreased in schizophrenia, but no difference was observed in processing strategy. Patients with schizophrenia may have special deficits in processing negative faces, and negative symptoms may affect visual scanning parameters.
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[Effects of tanyu tongzhi recipe on hemorheology, blood lipid and inflammatory factors in rats with mycardial ischemia-reperfusion injury and hyperlipidemia].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 05-16-2013
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To investigate the influence of Tanyu Tongzhi (TYTZ) recipe on chemorheology, blood lipid and inflammatory factors of hyperlipidemia and myocardial ischemia-reperfusion injury in rats.
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[Pro-apoptotic effects of curcumin associated with CIK cells against ovarian carcinoma cells].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-11-2013
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To observe the pro-apoptotic effects of Curcumin associated with CIK cells against SKOV3 cells of ovarian carcinoma and discusses the possible molecular mechanisms.
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D-isoascorbyl palmitate: lipase-catalyzed synthesis, structural characterization and process optimization using response surface methodology.
Chem Cent J
PUBLISHED: 05-09-2013
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Isoascorbic acid is a stereoisomer of L-ascorbic acid, and widely used as a food antioxidant. However, its highly hydrophilic behavior prevents its application in cosmetics or fats and oils-based foods. To overcome this problem, D-isoascorbyl palmitate was synthesized in the present study for improving the isoascorbic acids oil solubility with an immobilized lipase in organic media. The structural information of synthesized product was clarified using LC-ESI-MS, FT-IR, 1H and 13C NMR analysis, and process parameters for high yield of D-isoascorbyl palmitate were optimized by using One-factor-at-a-time experiments and response surface methodology (RSM).
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Optimized pregelatinized starch technique for cell block preparation in cell cultures.
Exp. Mol. Pathol.
PUBLISHED: 03-11-2013
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The aim of the present study was to optimize the pregelatinized starch technique for cell block preparation and apply this approach in cultured cells of all types of growing forms, suspension and adherent. In order to evenly mix the starch powder and the cell suspension, we crafted a special plastic dropper. To prove the effectiveness of this optimized technique we used different cell lines, NCI-H69, NCI-H345, HCT-116, SKBR3 and MDA-MB-231. The morphology features, immunocytochemistry (ICC) and fluorescent/chromogenic in-situ hybridization (FISH/CISH) on the cell block sections were evaluated. The morphology features, the ICC and ISH results of cell block sections prepared by the new method were satisfactory comparing with the results obtained in biopsies, the gold standard test for this kind of analysis. The most attractive advantage of our optimized pregelatinized starch technique is that this new method is based on cell suspensions instead of cell sediment, so with our technique every section will contain cells due to the even distribution of the starch powder and the cells forming a homogeneous cell block. To the authors knowledge, this is the first description on cell block preparation based on cell suspension.
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Clinical and epidemiological study on severe fever with thrombocytopenia syndrome in Yiyuan County, Shandong Province, China.
Am. J. Trop. Med. Hyg.
PUBLISHED: 01-21-2013
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Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease in China. Polymerase chain reaction and enzyme-linked immunosorbent assay were used to detect SFTS virus (SFTSV) and Anaplasma phagocytophilum in previous clinically diagnosed human anaplasmosis patients and SFTS patients. A serosurvey for SFTSV infection was also conducted on healthy persons and animals in Yiyuan County in Shandong Province of China. Among 21 patients SFTSV was detected in 17 (81%) however A. phagocytophilum was not detected in any of the patients. The seroprevalence rate of IgG antibody to SFTSV antigens was 1.3% (1 of 78) in healthy persons, 95% (19 of 20) in goats, 50% (1 of 2) in dogs, 0% in cattle (0 of 21), and rats (Rattus norvegicus) (0 of 35). The conclusion of this study was that co-infection of SFTSV and A. phagocytophilum are rare in SFTS patients and goats might play an important role in transmission of SFTSV.
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Synthesis and biological evaluation of a class of quinolone triazoles as potential antimicrobial agents and their interactions with calf thymus DNA.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-17-2013
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A novel series of quinolone triazoles were synthesized and characterized by IR, NMR, MS and HRMS spectra. All the newly prepared compounds were screened for their antimicrobial activities against seven bacteria and four fungi. Bioactive assay manifested that most of new compounds exhibited good or even stronger antibacterial and antifungal activities against the tested strains including multi-drug resistant MRSA in comparison with reference drugs Norfloxacin, Chloromycin and Fluconazole. The preliminary interactive investigations of compound 6b with calf thymus DNA by fluorescence and UV-vis spectroscopic methods revealed that compound 6b could effectively intercalate DNA to form compound 6b-DNA complex which might block DNA replication and thus exert its antimicrobial activities.
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Enhanced electricity generation by using algae biomass and activated sludge in microbial fuel cell.
Sci. Total Environ.
PUBLISHED: 01-16-2013
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Recently, interest is growing to explore low-cost and sustainable means of energy production. In this study, we have exploited the potential of sustainable energy production from wastes. Activated sludge and algae biomass are used as substrates in microbial fuel cell (MFC) to produce electricity. Activated sludge is used at anode as inoculum and nutrient source. Various concentrations (1-5 g/L) of dry algae biomass are tested. Among tested concentrations, 5 g/L (5000 mg COD/L) produced the highest voltage of 0.89 V and power density of 1.78 W/m(2) under 1000 ? electric resistance. Pre-treated algae biomass and activated sludge are also used at anode. They give low power output than without pre-treatment. Spent algae biomass is tested to replace whole (before oil extraction) algae biomass as a substrate, but it gives low power output. This work has proved the concept of using algae biomass in MFC for high energy output.
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A plant-specific in vitro ubiquitination analysis system.
Plant J.
PUBLISHED: 01-15-2013
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Protein ubiquitination requires the concerted action of three enzymes: ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2) and ubiquitin ligase (E3). These ubiquitination enzymes belong to an abundant protein family that is encoded in all eukaryotic genomes. Describing their biochemical characteristics is an important part of their functional analysis. It has been recognized that various E2/E3 specificities exist, and that detection of E3 ubiquitination activity in vitro may depend on the recruitment of E2s. Here, we describe the development of an in vitro ubiquitination system based on proteins encoded by genes from Arabidopsis. It includes most varieties of Arabidopsis E2 proteins, which are tested with several RING-finger type E3 ligases. This system permits determination of E3 activity in combination with most of the E2 sub-groups that have been identified in the Arabidopsis genome. At the same time, E2/E3 specificities have also been explored. The components used in this system are all from plants, particularly Arabidopsis, making it very suitable for ubiquitination assays of plant proteins. Some E2 proteins that are not easily expressed in Escherichia coli were transiently expressed and purified from plants before use in ubiquitination assays. This system is also adaptable to proteins of species other than plants. In this system, we also analyzed two mutated forms of ubiquitin, K48R and K63R, to detect various types of ubiquitin conjugation.
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Altered immunity in crowded locust reduced fungal (Metarhizium anisopliae) pathogenesis.
PLoS Pathog.
PUBLISHED: 01-10-2013
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The stress of living conditions, similar to infections, alters animal immunity. High population density is empirically considered to induce prophylactic immunity to reduce the infection risk, which was challenged by a model of low connectivity between infectious and susceptible individuals in crowded animals. The migratory locust, which exhibits polyphenism through gregarious and solitary phases in response to population density and displays different resistance to fungal biopesticide (Metarhizium anisopliae), was used to observe the prophylactic immunity of crowded animals. We applied an RNA-sequencing assay to investigate differential expression in fat body samples of gregarious and solitary locusts before and after infection. Solitary locusts devoted at least twice the number of genes for combating M. anisopliae infection than gregarious locusts. The transcription of immune molecules such as pattern recognition proteins, protease inhibitors, and anti-oxidation proteins, was increased in prophylactic immunity of gregarious locusts. The differentially expressed transcripts reducing gregarious locust susceptibility to M. anisopliae were confirmed at the transcriptional and translational level. Further investigation revealed that locust GNBP3 was susceptible to proteolysis while GNBP1, induced by M. anisopliae infection, resisted proteolysis. Silencing of gnbp3 by RNAi significantly shortened the life span of gregarious locusts but not solitary locusts. By contrast, gnbp1 silencing did not affect the life span of both gregarious and solitary locusts after M. anisopliae infection. Thus, the GNBP3-dependent immune responses were involved in the phenotypic resistance of gregarious locusts to fungal infection, but were redundant in solitary locusts. Our results indicated that gregarious locusts prophylactically activated upstream modulators of immune cascades rather than downstream effectors, preferring to quarantine rather than eliminate pathogens to conserve energy meanwhile increasing the "distance" of infectious and target individuals. Our study has obvious implications for bio-pesticides management of crowded pests, and for understanding disease epidemics and adaptiveness of pathogens.
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Radon-induced alterations in micro-RNA expression profiles in transformed BEAS2B cells.
J. Toxicol. Environ. Health Part A
PUBLISHED: 01-09-2013
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Radon and its progeny are confirmed to be type I carcinogenic agents accounting for increased risks in 10% of observed lung cancers globally. However, the underlying carcinogenic mechanisms are largely unknown. In the present study, BEAS2B cells were directly exposed twice to 20,000 Bq/m(3) radon gas for 20 min once (first passage) and subsequently 10 times (fifth passage). The fifth-passage cells were then subcultured for 1 and 20 generations (named Rn5-1 and Rn5-20, respectively). Molecular mechanisms indicative of malignant transformation were assessed by determination of apoptosis, seroresistance, and microRNA (miRNA) expression profiles. The microRNA profiles were used to assess the functional annotations of the target genes. Data indicated an increased seroresistance and colony efficiency on soft agar, and enhanced apoptosis resistance in the Rn5-20 cells with significant differential expressions in some miRNA, including hsa-miR-483-3p, hsa-miR-494, hsa-miR-2115*, hsa-miR-33b, hsa-miR-1246, hsa-miR-3202, hsa-miR-18a, hsa-miR-125b, hsa-miR-17*, and hsa-miR-886-3p. Functional annotation demonstrated that these miRNA target genes were predominantly involved in the regulation of cell proliferation, differentiation, and adhesion during the process of malignant transformation, which is associated with signal pathways such as mitogen-activated protein kinase (MAPK), Int and Wg (Wnt), reactive oxygen species (ROS), nuclear factor ?B (NF-?B), and other genes regulating cell cycles.
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Spatial analysis of hemorrhagic fever with renal syndrome in Zibo City, China, 2009-2012.
PLoS ONE
PUBLISHED: 01-01-2013
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Hemorrhagic fever with renal syndrome (HFRS) is highly endemic in mainland China, where human cases account for 90% of the total global cases. Zibo City is one of the most serious affected areas in Shandong Province China with the HFRS incidence increasing sharply from 2009 to 2012. However, the hotspots of HFRS in Zibo remained unclear. Thus, a spatial analysis was conducted with the aim to explore the spatial, spatial-temporal and seasonal patterns of HFRS in Zibo from 2009 to 2012, and to provide guidance for formulating regional prevention and control strategies.
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[TNF? induced IL-8 production through p38 MAPK- NF-kB pathway in human hepatocellular carcinoma cells].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 12-29-2011
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To identify the role of p38 MAPK- NF-kB signaling pathway in TNF-? induced IL-8 production in human hepatocellular carcinoma cells.
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[Surveillance of schistosomiasis in Hubei section of the Three Gorge Reservoir areas, 2007 - 2009].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 12-15-2011
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The source of infection of schistosomiasis and snail situation in Hubei section of the Three Gorge Reservoir areas from 2007 to 2009 were investigated by combined epidemiological, immunological and field survey. The results showed that there were no local residents and livestock infected with shchistosome, and no Oncomelania snails were found, but 4 cases of imported patients with chronic schistosomiasis were checked out. It is suggested that the surveillance and intervention should be strengthened pointing to the risk of schistosomiasis transmission in the Three Gorge Reservoir areas, so as to prevent schistosomiasis being endemic in these areas.
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Synthesis and characterization of nano-PVP/EuL3 luminescent complex.
J Nanosci Nanotechnol
PUBLISHED: 11-15-2011
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Nano-sized rare earth europium [Eu(III)]-benzoic acid [HL] luminescent complex powders have been synthesized in polyvinylpyrrolidone matrix by precipitation method. The chemical constitution of the complex has been demonstrated as PVP/EuL3 by a combination of elemental analysis, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and fourier-transform infrared spectroscopy (FT-IR). X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) have shown that the complex is a new nanocrystal whose structure is totally different from the ligand. Thermogravimetric/Differential thermal analysis (TG/DTA) have indicated that the luminescent complex is thermally stable below 500 degrees C. Photoluminescence spectra (PL) have shown that the nanocomplex can emit Eu3+ characteristic red fluorescence under ultraviolet excitation.
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Design, fabrication and levitation experiments of a micromachined electrostatically suspended six-axis accelerometer.
Sensors (Basel)
PUBLISHED: 10-22-2011
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A micromachined electrostatically suspended six-axis accelerometer, with a square plate as proof mass housed by a top stator and bottom stator, is presented. The device structure and related techniques concerning its operating principles, such as calculation of capacitances and electrostatic forces/moments, detection and levitation control of the proof mass, acceleration measurement, and structural parameters design, are described. Hybrid MEMS manufacturing techniques, including surface micromachining fabrication of thin film electrodes and interconnections, integration fabrication of thick nickel structures about 500 ?m using UV-LIGA by successful removal of SU-8 photoresist mold, DRIE of silicon proof mass in thickness of 450 ?m, microassembly and solder bonding, were employed to fabricate this prototype microdevice. A levitation experiment system for the fabricated microaccelerometer chip is introduced, and levitation results show that fast initial levitation within 10 ms and stable full suspension of the proof mass have been successfully demonstrated.
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Correlation between carboxylesterase alleles and insecticide resistance in Culex pipiens complex from China.
Parasit Vectors
PUBLISHED: 10-17-2011
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In China, large amounts of chemical insecticides are applied in fields or indoors every year, directly or indirectly bringing selection pressure on vector mosquitoes. Culex pipiens complex has evolved to be resistant to all types of chemical insecticides, especially organophosphates, through carboxylesterases. Six resistant carboxylesterase alleles (Ester) were recorded previously and sometimes co-existed in one field population, representing a complex situation for the evolution of Ester genes.
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[Pleiotropic drug resistance ABC transporters in fungi].
Yi Chuan
PUBLISHED: 10-14-2011
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Overexpression of pleiotropic drug resistance (PDR) efflux pumps of the ATP-binding cassette (ABC) transporter superfamily is the major cause of fungal multi-drug resistance and decreased efficacy of antifungal drugs. This review focused on recent progresses in understanding of the PDR efflux pumps of ABC transporter superfamily in Saccharomyces cerevisiae and the fungal pathogens Candida albicans, Cryptococcus neoformans, and Aspergillus fumigates. The mechanisms underlying efflux pump-mediated drug resistance and the regulatory networks involved were discussed. Investigation of the PDR efflux pumps of ABC transporter superfamily and their impact on drug resistance may lead to strategies to overcome fungal multi-drug resistance and improve drug efficacy.
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POD1 regulates pollen tube guidance in response to micropylar female signaling and acts in early embryo patterning in Arabidopsis.
Plant Cell
PUBLISHED: 09-27-2011
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The pollen tube germinates from pollen and, during its migration, it perceives and responds to guidance cues from maternal tissue and from the female gametophyte. The putative female cues have recently been identified, but how the pollen tube responds to these signals remains to be unveiled. In a genetic screen for male determinants of the pollen tube response, we identified the pollen defective in guidance1 (pod1) mutant, in which the pollen tubes fail to target the female gametophyte. POD1 encodes a conserved protein of unknown function and is essential for positioning and orienting the cell division plane during early embryo development. Here, we demonstrate that POD1 is an endoplasmic reticulum (ER) luminal protein involved in ER protein retention. Further analysis shows that POD1 interacts with the Ca(2+) binding ER chaperone CALRETICULIN3 (CRT3), a protein in charge of folding of membrane receptors. We propose that POD1 modulates the activity of CRT3 or other ER resident factors to control the folding of proteins, such as membrane proteins in the ER. By this mechanism, POD1 may regulate the pollen tube response to signals from the female tissues during pollen tube guidance and early embryo patterning in Arabidopsis thaliana.
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SPT6L encoding a putative WG/GW-repeat protein regulates apical-basal polarity of embryo in Arabidopsis.
Mol Plant
PUBLISHED: 09-23-2011
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In eukaryotes, a protein motif consisting of WG/GW repeats, also called the Argonaute (AGO) hook, is thought to be essential for binding AGO proteins to fulfill their functions in RNA-mediated gene silencing. Although a number of WG/GW-containing proteins have been computationally identified in Arabidopsis, their roles in plant growth and development are unknown. Here, we show that the Arabidopsis Suppressor of Ty insertion 6-like (SPT6L) gene, which encodes a protein with C-terminal WG/GW repeats, plays critical roles in embryonic development. SPT6L is evolutionarily conserved only in vascular plants, with varying numbers of C-terminal WG/GW repeats, which are plant-species specific. spt6l mutants formed embryos with an aberrant apical-basal axis, showing insufficient development of the basal domain and embryonic lethality. Expression domains of the class-III homeodomain-leucine zipper (HD-ZIP III) genes PHABULOSA (PHB) and PHAVOLUTA (PHV) were expanded in the spt6l embryo. In contrast, the PLETHORA1 (PLT1) gene, which acts antagonistically to the HD-ZIP III genes in specification of basal fate, was severely down-regulated in the spt6l mutant. Furthermore, the phb phv double mutations partially rescued aberrant basal development in the spt6l background and restored PLT1 expression. Collectively, our results indicate that SPT6L is essential for specification of the apical-basal axis, partly by controlling the HD-ZIP III genes in embryos.
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Regulation of NMDA receptor subunits after acute ethanol treatment in rat brain.
Alcohol Alcohol.
PUBLISHED: 09-08-2011
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Tolerance to ethanol-induced inhibition of N-methyl-D-aspartate receptors (NMDARs) is thought to underlie the acute adaptive mechanisms against ethanol. To explore these compensatory upregulating mechanisms of NMDARs, we investigated the expression and phosphorylation of NMDAR subunits in vivo following an acute ethanol treatment.
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Simultaneous identification and quantification of canrenone and 11-?-hydroxy-canrenone by LC-MS and HPLC-UVD.
J. Biomed. Biotechnol.
PUBLISHED: 08-24-2011
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A procedure for simultaneous identification and quantification of canrenone and its biotransformed product 11-?-hydroxy-canrenone by high-performance liquid chromatography with ultraviolet detector (HPLC-UVD) and mass spectrometry (LC-MS) methods was proposed. The optimal determination variables on the HPLC-UVD or LC-MS coupled with a ZORBAX Eclipse XDB-C18 column (150?mm × 4.6?mm, 5??m) were set as follows: detection wavelength of 280?nm, mobile phase of water and methanol gradient elution, temperature for the chromatographic column of 30°C, flow rate of mobile phase of 0.8?mL/min, sample injection volume of 5??L, and elution time of 40?min. The MS conditions were set as follows: the flow rate of sheath gas, aux gas, and sweep gas were kept at 35 arb, 5 arb, and 0 arb, respectively. The temperature of capillary was held at 300°C, and capillary voltage was set at 30.00?V. Tube lens were performed at 100.00?V. The proposed method was validated by linearity (r² ? 0.9910), average recovery (94.93%, RSD1.21%), precision (RSD ? 1.31%), limit of detection, and limit of quantification (LOD 0.1~0.12?mg/L, LOQ 0.5~0.67?mg/L), which proved to be affordable for simultaneously determining canrenone and its bio-transformed product 11-?-hydroxy-canrenone.
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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.

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

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