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Aqueous Transition Metal Cations as Impurities in a Wide Gap Oxide: The Cu(2+)/Cu(1+) and Ag(2+)/Ag(1+) Redox Couples Revisited.
J Phys Chem B
PUBLISHED: 11-12-2014
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The interactions of the d electrons of transition metal aqua ions with the solvent are usually divided in short range electronic interactions with ligand water molecules and long range electrostatic interactions with molecules beyond the first coordination shell. This is the rationale behind the cluster continuum and QM/MM methods developed for the computation of the redox potentials. In the density functional theory based molecular dynamics (DFTMD) method the electronic states of the complex are also allowed to mix with the extended band states of the solvent. Returning to the Cu^1+ and Ag^1+ oxidation reaction which has been the subject of DFTMD simulation before we show that coupling to the valence band states of water is greatly enhanced by the band gap error in the density functional approximation commonly used in DFTMD (the generalized gradient approximation). This effect is analyzed by viewing the solvent as a wide gap oxide and the redox active ions as electronic defects. The errors can be reduced significantly by application of hybrid functionals containing a fraction of Hartree-Fock exchange. These calculations make use of recent progress in DFTMD technology enabling us to include sp core polarization and Hartree-Fock exchange in condensed phase model systems.
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Surface acidity of quartz: understanding the crystallographic control.
Phys Chem Chem Phys
PUBLISHED: 11-07-2014
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We report a first principles molecular dynamics (FPMD) study of surface acid chemistry of the two growth surfaces of quartz, (101[combining macron]0) (including Alpha and Beta terminations) and (101[combining macron]1) facets. The interfacial hydration structures are characterized in detail and the intrinsic pKas of surface silanols are evaluated using the FPMD based vertical energy gap method. The calculated acidity constants reveal that every surface termination shows a bimodal acid-base behavior. It is found that all doubly-protonated forms (i.e. SiOH2) on the three terminations have pKas lower than -2.5, implying that the silanols hardly get protonated in a common pH range. The pKas of surface silanols can be divided into 3 groups. The most acidic silanol is the donor SiOH on the (101[combining macron]0)-beta surface (pKa = 4.8), the medium includes the germinal silanol on (101[combining macron]0)-alpha and the outer silanol on (101[combining macron]1) (pKa = 8.5-9.3) and the least acidic are inner silanols on the (101[combining macron]1)-facet, acceptor SiOH on (101[combining macron]0)-beta, and the secondly-deprotonated OH (i.e. Si(O-)(OH)) on (101[combining macron]0)-alpha (pKa > 11.0). With the pKa values, we discuss the implication for understanding metal cations complexing on quartz surfaces.
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Redox Potentials and Acidity Constants from Density Functional Theory Based Molecular Dynamics.
Acc. Chem. Res.
PUBLISHED: 11-04-2014
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Conspectus All-atom methods treat solute and solvent at the same level of electronic structure theory and statistical mechanics. All-atom computation of acidity constants (pKa) and redox potentials is still a challenge. In this Account, we review such a method combining density functional theory based molecular dynamics (DFTMD) and free energy perturbation (FEP) methods. The key computational tool is a FEP based method for reversible insertion of a proton or electron in a periodic DFTMD model system. The free energy of insertion (work function) is computed by thermodynamic integration of vertical energy gaps obtained from total energy differences. The problem of the loss of a physical reference for ionization energies under periodic boundary conditions is solved by comparing with the proton work function computed for the same supercell. The scheme acts as a computational hydrogen electrode, and the DFTMD redox energies can be directly compared with experimental redox potentials. Consistent with the closed shell nature of acid dissociation, pKa estimates computed using the proton insertion/removal scheme are found to be significantly more accurate than the redox potential calculations. This enables us to separate the DFT error from other sources of uncertainty such as finite system size and sampling errors. Drawing an analogy with charged defects in solids, we trace the error in redox potentials back to underestimation of the energy gap of the extended states of the solvent. Accordingly the improvement in the redox potential as calculated by hybrid functionals is explained as a consequence of the opening up of the bandgap by the Hartree-Fock exchange component in hybrids. Test calculations for a number of small inorganic and organic molecules show that the hybrid functional implementation of our method can reproduce acidity constants with an uncertainty of 1-2 pKa units (0.1 eV). The error for redox potentials is in the order of 0.2 V.
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Frontispiece: Aligning Electronic and Protonic Energy Levels of Proton-Coupled Electron Transfer in Water Oxidation on Aqueous TiO2.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 10-29-2014
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Proton-Coupled Electron Transfer In their Communication on page?12046?ff., J. Cheng et?al. propose the concept of protonic energy levels to visualize the thermodynamics of proton-coupled electron transfer. Their method helps to elucidate the electronic and protonic components of thermodynamic overpotentials in photocatalysis.
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Automated analysis of angle closure from anterior chamber angle images.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 10-23-2014
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Purpose:To evaluate a novel software capable of automatically grading angle closure on EyeCamTM (Clarity Medical Systems, Pleasanton, CA) angle images in comparison to manual grading of images, with gonioscopy as the reference standard. Methods:In this hospital-based, prospective study, subjects underwent gonioscopy by a single observer, and EyeCam imaging by a different operator. The anterior chamber angle in a quadrant was classified as closed if the posterior trabecular meshwork could not be seen. An eye was classified as having angle closure if there were 2 or more quadrants of closure. Automated grading of the angle images was performed using customized software. Agreement between the methods was ascertained by kappa statistic and comparison of area under receiver operating characteristic curves (AUC). Results:One hundred and forty subjects (140 eyes) were included, the majority of whom were Chinese (102/140, 72.9%) and females (72/140, 51.5%). Angle closure was detected in 61 eyes (43.6%) with gonioscopy in comparison to 59 eyes (42.1%, p=0.73) using manual grading and 67 eyes (47.9%, p=0.24) with automated grading of EyeCam images. The agreement for angle closure diagnosis between gonioscopy and both manual (k=0.88; 95% Confidence Interval (CI), 0.81-0.96) and automated grading of EyeCam images was good (k=0.74; 95% CI, 0.63-0.85). The AUC for detecting eyes with gonioscopic angle closure was comparable for manual and automated grading (AUC 0.974 vs 0.954, p = 0.31) of EyeCam image. Conclusions:Customized software for automated grading of EyeCam angle images was found to have good agreement with gonioscopy. Human observation of the EyeCam images may still be needed to avoid gross misclassification, especially in eyes with extensive angle closure.
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Speckle reduction in optical coherence tomography by image registration and matrix completion.
Med Image Comput Comput Assist Interv
PUBLISHED: 10-22-2014
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Speckle noise is problematic in optical coherence tomography (OCT). With the fast scan rate, swept source OCT scans the same position in the retina for multiple times rapidly and computes an average image from the multiple scans for speckle reduction. However, the eye movement poses some challenges. In this paper, we propose a new method for speckle reduction from multiply-scanned OCT slices. The proposed method applies a preliminary speckle reduction on the OCT slices and then registers them using a global alignment followed by a local alignment based on fast iterative diamond search. After that, low rank matrix completion using bilateral random projection is utilized to iteratively estimate the noise and recover the underlying clean image. Experimental results show that the proposed method achieves average contrast to noise ratio 15.65, better than 13.78 by the baseline method used currently in swept source OCT devices. The technology can be embedded into current OCT machines to enhance the image quality for subsequent analysis.
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Simultaneous immunolocalization of desmoglein 3 and IgG4 in oral pemphigus vulgaris: IgG4 predominant autoantibodies in its pathogenesis.
J. Oral Pathol. Med.
PUBLISHED: 10-16-2014
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Oral pemphigus vulgaris (PV), an autoimmune blistering disease, is mainly mediated by autoantibodies against desmoglein (Dsg) 3. However, no attention has been paid to IgG subclasses of the autoantibodies against Dsg3 in the diagnostic procedure for PV. Thus, our aim in this study was to investigate whether Dsg3 and any of IgG subclasses are immunohistochemically colocalized in tissue sections of PV oral mucosa.
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A Randomized, Three-arm Study to Optimize Lamivudine Efficacy in HBeAg Positive Chronic Hepatitis B Patients.
J. Gastroenterol. Hepatol.
PUBLISHED: 10-14-2014
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To compare the efficacy at week 104 of lamivudine monotherapy (MONO), lamivudine plus adefovir dipivoxil (ADV) combination therapy (COMBO), and lamivudine optimization strategy (OPTIMIZE).
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NS5ATP9 Suppresses Activation of Human Hepatic Stellate Cells, Possibly via Inhibition of Smad3/Phosphorylated-Smad3 Expression.
Inflammation
PUBLISHED: 10-11-2014
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Activation of hepatic stellate cell (HSC) is the central event in liver fibrosis. NS5ATP9 is related to many malignant tumors, but little is known about its function in HSC activation. The aim of this study is to investigate the role of NS5ATP9 in HSC activation in vitro. Genes related to liver fibrosis were detected after NS5ATP9 overexpression or silencing with or without transforming growth factor (TGF)-?1 stimulation in the human HSCs by real-time polymerase chain reaction and western blotting. Cell proliferation, migration, and apoptosis were tested, and the mechanisms underlying the effect of NS5ATP9 on HSC activation were studied. We showed that NS5ATP9 suppressed HSC activation and collagen production, with or without TGF-?1 induction. Also, NS5ATP9 inhibited cell proliferation and migration and promoted apoptosis. Furthermore, NS5ATP9 reduced basal and TGF-?1-mediated Smad3/phosphorylated-Smad3 expression. The existence of a physical complex between NS5ATP9 and Smad3 was illustrated. NS5ATP9 suppresses HSC activation, extracellular matrix production, and promotes apoptosis, in part through reducing Smad3/phosphorylated-Smad3 expression.
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Deoxycholic acid-modified chitooligosaccharide/mPEG-PDLLA mixed micelles loaded with paclitaxel for enhanced antitumor efficacy.
Int J Pharm
PUBLISHED: 08-23-2014
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Poly(ethylene glycol) (PEG) as a block in polymeric micelles can prolong circulation life and reduce systemic clearance but decrease the cellular uptake. To overcome this limitation, a mixed micelle composed of deoxycholic acid-modified chitooligosaccharide (COS-DOCA) and methoxy poly(ethylene glycol)-polylactide copolymer (mPEG-PDLLA) was designed to load paclitaxel (PTX). The PTX-loaded mixed micelles was prepared by nanoprecipitation method with high drug-loading efficiency of 8.03% and encapsulation efficiency of 97.09% as well as small size (?40nm) and narrow size distribution. COS-DOCA/mPEG-PDLLA mixed micelles exhibited the sustained release property. Due to the positive charge and bioadhesive property of COS-DOCA, the cellular uptake of PTX in mixed micelles was higher in cancer cells but lower in macrophage cells compared to the mPEG-PDLLA micelles. The systemic toxicity of PTX in mixed micelles was much lower than Taxol using zebrafish as a toxicological model. Furthermore, the PTX-loaded COS-DOCA/mPEG-PDLLA mixed micelles can prolong the blood circulation time of PTX and enhance the antitumor efficacy in A549 lung xenograft model. Our findings indicate that COS-DOCA/mPEG-PDLLA mixed micelles could be a potential vehicle for enhanced delivery of anticancer drugs.
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Unraveling the mechanism underlying the glycosylation and methylation of anthocyanins in peach.
Plant Physiol.
PUBLISHED: 08-08-2014
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Modification of anthocyanin plays an important role in increasing its stability in plants. Here, six anthocyanins were identified in peach (Prunus persica), and their structural diversity is attributed to glycosylation and methylation. Interestingly, peach is quite similar to the wild species Prunus ferganensis but differs from both Prunus davidiana and Prunus kansueasis in terms of anthocyanin composition in flowers. This indicates that peach is probably domesticated from P. ferganensis. Subsequently, genes responsible for both methylation and glycosylation of anthocyanins were identified, and their spatiotemporal expression results in different patterns of anthocyanin accumulation in flowers, leaves, and fruits. Two tandem-duplicated genes encoding flavonoid 3-O-glycosyltransferase (F3GT) in peach, PpUGT78A1 and PpUGT78A2, showed different activity toward anthocyanin, providing an example of divergent evolution of F3GT genes in plants. Two genes encoding anthocyanin O-methyltransferase (AOMT), PpAOMT1 and PpAOMT2, are expressed in leaves and flowers, but only PpAOMT2 is responsible for the O-methylation of anthocyanins at the 3' position in peach. In addition, our study reveals a novel branch of UGT78 genes in plants that lack the highly conserved intron 2 of the UGT gene family, with a great variation of the amino acid residue at position 22 of the plant secondary product glycosyltransferase box. Our results not only provide insights into the mechanisms underlying anthocyanin glycosylation and methylation in peach but will also aid in future attempts to manipulate flavonoid biosynthesis in peach as well as in other plants.
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Fractal microstructure characterization of wet microalgal cells disrupted with ultrasonic cavitation for lipid extraction.
Bioresour. Technol.
PUBLISHED: 08-01-2014
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The effects of ultrasonic treatment on fractal microstructures of wet microalgal cells were investigated for lipid extraction. Fractal dimension of cells with distorted surfaces increased with power and ultrasonication time. Microalgal cells shrank owing to dehydration and cytomembranes were reduced to debris, but cell walls were not fragmented. When ultrasonication power increased from 0 to 500W for 30min, the fractal dimension of cells increased from 1.21 to 1.51, cell sizes decreased from 2.78 to 1.68?m and cell wall thickness decreased from 0.08 to 0.05?m. When ultrasonication time increased from 5 to 30min with a power of 150W, the fractal dimension of cells increased from 1.24 to 1.37, cell sizes decreased from 2.72 to 2.38?m and cell wall thickness first increased to a peak of 0.22?m and then decreased. Long-chain and unsaturated lipids were degraded into short-chain and saturated lipids with ultrasonic cavitation.
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Biodiesel from wet microalgae: extraction with hexane after the microwave-assisted transesterification of lipids.
Bioresour. Technol.
PUBLISHED: 08-01-2014
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A chloroform-free novel process for the efficient production of biodiesel from wet microalgae is proposed. Crude biodiesel is produced through extraction with hexane after microwave-assisted transesterification (EHMT) of lipids in wet microalgae. Effects of different parameters, including reaction temperature, reaction time, methanol dosage, and catalyst dosage, on fatty acids methyl esters (FAMEs) yield are investigated. The yield of FAME extracted into the hexane from the wet microalgae is increased 6-fold after the transesterification of lipids. The yield of FAME obtained through EHMT of lipids in wet microalgae is comparable to that obtained through direct transesterification of dried microalgae biomass with chloroform; however, FAME content in crude biodiesel obtained through EHMT is 86.74%, while that in crude biodiesel obtained through the chloroform-based process is 75.93%. EHMT ensures that polar pigments present in microalgae are not extracted into crude biodiesel, which leads to a 50% reduction in nitrogen content in crude biodiesel.
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Antioxidant-capacity-based models for the prediction of acrylamide reduction by flavonoids.
Food Chem
PUBLISHED: 07-10-2014
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The aim of this study was to investigate the applicability of artificial neural network (ANN) and multiple linear regression (MLR) models for the estimation of acrylamide reduction by flavonoids, using multiple antioxidant capacities of Maillard reaction products as variables via a microwave food processing workstation. The addition of selected flavonoids could effectively reduce acrylamide formation, which may be closely related to the number of phenolic hydroxyl groups of flavonoids (R: 0.735-0.951, P<0.001). The rate of inhibition of acrylamide formation correlated well with the change of trolox equivalent antioxidant capacity (?TEAC) measured by DPPH (R(2)=0.833), ABTS (R(2)=0.860) or FRAP (R(2)=0.824) assay. Both ANN and MLR models could effectively serve as predictive tools for estimating the reduction of acrylamide affected by flavonoids. The current predictive model study provides a low-cost and easy-to-use approach to the estimation of rates at which acrylamide is degraded, while avoiding tedious sample pretreatment procedures and advanced instrumental analysis.
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Irradiation facilitates the inhibitory effect of the heat shock protein 90 inhibitor NVP-BEP800 on the proliferation of malignant glioblastoma cells through attenuation of the upregulation of heat shock protein 70.
Exp Ther Med
PUBLISHED: 06-23-2014
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The present study aimed to investigate the effect of NVP-BEP800, a novel heat shock protein (Hsp) 90 inhibitor of the 2-aminothieno[2,3-d]pyrimidine class, in combination with radiation on glioblastoma cells. T98G human glioblastoma cells were treated with dimethyl sulfoxide (DMSO), NVP-BEP800, NVP-BEP800 in combination with X-ray irradiation (10 Gy, 20 min), or X-ray irradiation only, and cultured for 40 h. Cell viability was measured upon completion of the treatments. In addition, apoptosis was measured and immunoblot analysis was performed to analyze the expression levels of cellular protein inhibitory ?B kinase ? (IKK?). The combined treatment with NVP-BEP800 and X-ray irradiation resulted in the synergistic destruction of malignant cells. Furthermore, NVP-BEP800 significantly induced apoptosis in the human glioblastoma cells. The immunoblot analysis data indicated that NVP-BEP800 markedly reduced the expression level of IKK?. The results also revealed that X-ray irradiation significantly attenuated the increase in the level of Hsp70 in cells treated with NVP-BEP800. Since elevated levels of Hsp70 are associated with drug resistance induced by Hsp90 inhibitors, the effects of X-ray irradiation on Hsp70 levels may be associated with the enhanced effect on cells of the presence of irradiation. The results of the current study suggest that irradiation enhances the inhibitory effect of NVP-BEP800 on the proliferation of malignant glioblastoma cells by downregulating the expression level of cellular signaling protein IKK? and attenuating the upregulation of Hsp70 that is induced by NVP-BEP800.
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Renal abscess caused by Brucella.
Int. J. Infect. Dis.
PUBLISHED: 06-02-2014
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Involvement of the renal parenchyma in the acute phase of brucellosis is very rare. Only two cases of renal brucelloma have been reported in the English language literature to date. We report a case of renal abscess caused by Brucella in the acute phase. A 45-year-old Chinese man presented with a high fever, urine occult blood, and a low density lesion in the right kidney. Ultrasound-guided aspiration was done. Brucella melitensis was isolated from both blood and puncture fluid culture. Minocycline combined with moxifloxacin was prescribed for 4 months. The infection relapsed at 6 months after discontinuation. Minocycline combined with rifampin was administered for another 2 months. The brucellosis had not relapsed at more than 20 months later. It is possible to cure renal brucelloma with antibiotics and ultrasound-guided aspiration. Treatment should not be discontinued until the abscess has disappeared and two consecutive blood cultures taken 1 month apart are negative.
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Photoelectrocatalytic reduction of CO2 into chemicals using Pt-modified reduced graphene oxide combined with Pt-modified TiO2 nanotubes.
Environ. Sci. Technol.
PUBLISHED: 05-28-2014
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The photoelectrocatalytic (PEC) reduction of CO2 into high-value chemicals is beneficial in alleviating global warming and advancing a low-carbon economy. In this work, Pt-modified reduced graphene oxide (Pt-RGO) and Pt-modified TiO2 nanotubes (Pt-TNT) were combined as cathode and photoanode catalysts, respectively, to form a PEC reactor for converting CO2 into valuable chemicals. XRD, XPS, TEM, AFM, and SEM were employed to characterize the microstructures of the Pt-RGO and Pt-TNT catalysts. Reduction products, such as C2H5OH and CH3COOH, were obtained from CO2 under band gap illumination and biased voltage. A combined liquid product generation rate (CH3OH, C2H5OH, HCOOH, and CH3COOH) of approximately 600 nmol/(h·cm(2)) was observed. Carbon atom conversion rate reached 1,130 nmol/(h·cm(2)), which were much higher than those achieved using Pt-modified carbon nanotubes and platinum carbon as cathode catalysts.
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Stent-Graft Placement with Early Debridement and Antibiotic Treatment for Femoral Pseudoaneurysms in Intravenous Drug Addicts.
Cardiovasc Intervent Radiol
PUBLISHED: 05-26-2014
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Explore the application of endovascular covered stent-graft (SG) placement in femoral pseudoaneurysms in intravenous drug addicts.
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Aligning Electronic and Protonic Energy Levels of Proton-Coupled Electron Transfer in Water Oxidation on Aqueous TiO2.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 05-26-2014
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The high overpotential in water oxidation on anodes is a limiting factor for the large-scale application of photoelectrochemical cells. To overcome this limitation, it is essential to understand the four proton-coupled electron transfer (PCET) steps in the reaction mechanism and their implications to the overpotential. Herein, a simple scheme to compute the energies of the PCET steps in water oxidation on the aqueous TiO2 surface using a hybrid density functional is described. An energy level diagram for fully decoupled electron- and proton-transfer reactions in which both electronic and protonic levels are placed on the same potential scale is also described. The level diagram helps to visualize the electronic and protonic components of the overpotential, and points out what are needed to improve. For TiO2 , it is found that its catalytic activity is due to aligning the protonic energy levels in the PCET steps, while improving the activity requires also aligning the electronic levels.
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Transactivation of proto-oncogene c-Myc by hepatitis B virus transactivator MHBs(t167.)
Oncol Lett
PUBLISHED: 04-29-2014
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C-terminally truncated hepatitis B virus (HBV) middle size surface proteins (MHBs(t)) has been shown to be a transcriptional activator and may be relevant to hepatocarcinogenesis by transactivating gene expression. In the present study, a pcDNA3.1(-)-MHBs(t167) vector coding for MHBs(t) truncated at amino acid 167 (MHBs(t167)) was constructed and transfected into the HepG2 hepatoma cell line. mRNA and protein expression of MHBs(t167) in the cells was detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis. A cDNA library of genes transactivated by the truncated protein in HepG2 cells was made in pGEM-T Easy using suppression subtractive hybridization. The cDNAs were sequenced and analyzed with BLAST searching against the sequences in GenBank. The results showed that certain sequences, such as that of human proto-oncogene c-Myc, may be involved in tumor development. An expression vector pCAT3/c-Myc containing the chloramphenicol acetyltransferase (CAT) gene under the control of a c-Myc promoter was generated, and the transcriptional transactivating effect of MHBs(t167) on the c-Myc promoter was investigated by RT-PCR and western blotting. MHBs(t167) was found to upregulate the transcriptional activity of the promoter, as well as transcription and translation of c-Myc. MHBs(t167) was also shown to transactivate SV40 immediate early promoter, and transcriptionally transactivate the expression of human c-Myc. These findings provide new directions for studying the biological functions of MHBs(t167), and for a better understanding of the tumor development mechanisms of HBV infection.
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A study of the optical properties of metal-doped polyoxotitanium cages and the relationship to metal-doped titania.
Dalton Trans
PUBLISHED: 04-26-2014
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To what extent the presence of transition metal ions can affect the optical properties of structurally well-defined, metal-doped polyoxotitanium (POT) cages is a key question in respect to how closely these species model technologically important metal-doped TiO2. This also has direct implications to the potential applications of these organically-soluble inorganic cages as photocatalytic redox systems in chemical transformations. Measurement of the band gaps of the series of closely related polyoxotitanium cages [MnTi14(OEt)28O14(OH)2] (1), [FeTi14(OEt)28O14(OH)2] (2) and [GaTi14(OEt)28O15(OH)] (3), containing interstitial Mn(II), Fe(II) and Ga(III) dopant ions, shows that transition metal doping alone does not lower the band gaps below that of TiO2 or the corresponding metal-doped TiO2. Instead, the band gaps of these cages are within the range of values found previously for transition metal-doped TiO2 nanoparticles. The low band gaps previously reported for 1 and for a recently reported related Mn-doped POT cage appear to be the result of low band gap impurities (most likely amorphous Mn-doped TiO2).
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Screening of hepatocyte proteins binding with C?terminally truncated surface antigen middle protein of hepatitis B virus (MHBst167) by a yeast two?hybrid system.
Mol Med Rep
PUBLISHED: 04-25-2014
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The function of middle hepatitis B surface protein C?terminally truncated at amino acid position 167 (MHBst167) is not currently clear. This study aimed to screen and identify the proteins that interact with MHBst167 in hepatocytes using a yeast two?hybrid system, and to explore the effects of MHBst167 in the development of hepatocellular carcinoma and precancerous diseases of the liver. The MHBst167 gene was amplified by polymerase chain reaction (PCR) and cloned into a pGEM?T vector. The target region was sequenced and the constructed bait plasmid, pGBKT7?MHBst167, was transformed into AH109 yeast cells. The transformed AH109 cells were then mated with Y187 yeast cells containing the fetal liver cDNA library plasmid using a yeast two?hybrid system. The false positives were eliminated and the true positive clones were selected by PCR and sequencing analysis. The pGBKT7?MHBst167 bait plasmid was successfully constructed and 66 clones grew in the selective synthetic defined media lacking leucine, tryptophan, histidine and adenine. Fifty?two clones were identified following X???Gal selection and segregation analysis. Seven proteins were found to be expressed that could interact with MHBst167 in hepatocytes by the yeast two?hybrid system. These results have provided novel insights into the biological functions of MHBst167.
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Hepatic encephalomyelopathy: a complication following liver cirrhosis caused by Budd-Chiari syndrome and HBV.
J Infect Dev Ctries
PUBLISHED: 04-15-2014
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Progressive encephalomyelopathy is a rare neurological complication of chronic liver disease, even manifesting progressive spastic paraparesis. Few reports detailing the clinical and diagnostic aspects of this uncommon cause of neurological deterioration in patients with hepatic insufficiency have been published. Early recognition of this disorder will become more important in the future as patients with liver disease survive longer due to medical advances, including liver transplantation. The case of a patient with hepatic encephalomyelopathy associated with Budd-Chiari syndrome and HBV-related cirrhosis is presented.
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Effect of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers on all-cause mortality, cardiovascular deaths, and cardiovascular events in patients with diabetes mellitus: a meta-analysis.
JAMA Intern Med
PUBLISHED: 04-02-2014
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Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) may have different effects on cardiovascular (CV) events in patients with diabetes mellitus (DM).
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Keratin pearl degradation in oral squamous cell carcinoma: reciprocal roles of neutrophils and macrophages.
J. Oral Pathol. Med.
PUBLISHED: 03-27-2014
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We have reported that neutrophilic infiltration was associated with round-shaped dyskeratosis foci, a kind of keratin pearl, of oral carcinoma in situ and that those inflammatory cells are recruited from intra-epithelially entrapped blood vessels. Based on these lines of evidence, we have formulated a hypothesis that keratin pearls are terminally degraded by neutrophils. To confirm this hypothesis, we investigated immunohistochemically stepwise degradation of keratin pearls in oral squamous cell carcinoma (SCC) to clarify any other type scavenger cells in addition to neutrophils are involved in this particular degradation process.
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MicroRNA-145 suppresses hepatocellular carcinoma by targeting IRS1 and its downstream Akt signaling.
Biochem. Biophys. Res. Commun.
PUBLISHED: 03-19-2014
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Accumulating evidences have proved that dysregulation of microRNAs (miRNAs) is involved in cancer initiation and progression. In this study, we showed that miRNA-145 level was significantly decreased in hepatocellular cancer (HCC) tissues and cell lines, and its low expression was inversely associated with the abundance of insulin receptor substrate 1 (IRS1), a key mediator in oncogenic insulin-like growth factor (IGF) signaling. We verified IRS1 as a direct target of miR-145 using Western blotting and luciferase reporter assay. Further, the restoration of miR-145 in HCC cell lines suppressed cancer cell growth, owing to down-regulated IRS1 expression and its downstream Akt/FOXO1 signaling. Our results demonstrated that miR-145 could inhibit HCC through targeting IRS1 and its downstream signaling, implicating the loss of miR-145 regulation may be a potential molecular mechanism causing aberrant oncogenic signaling in HCC.
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Antimicrobial resistance patterns and characterization of integrons in clinical isolates of Shigella from China.
Can. J. Microbiol.
PUBLISHED: 03-07-2014
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One hundred fifty-three Shigella isolates were examined for multiple antibiotic resistance phenotypes and prevalence of class 1 and class 2 integron sequences. The gene cassettes dfrA17-aadA5, dfrA12-orfF-aadA2, and arr-3-aacA4 were found in typical class 1 integrons. The gene cassettes blaOXA-1-aadA1 and dfrA1-sat1-aadA1 were detected in atypical class 1 integrons and in class 2 integrons, respectively. This is the first report of arr-3-aacA4 cassette detected in typical class 1 integrons among Shigella isolates. Rates of antibiotic resistance were different between integron-positive and integron-negative strains (P < 0.05), and all integron-positive isolates were resistant to at least 3 different antimicrobial agents. Typical class 1 integron-positive isolates showed higher resistance rates to cefotaxime and ciprofloxacin than did integron-negative ones (P < 0.05). Typical class 1 integrons and ?-lactamase genes were found in conjugative plasmids, otherwise class 2 and atypical class 1 integrons were located on chromosome. This study demonstrated the wide distribution of class 1 integrons in Shigella spp., which may lead resistance to cefotaxime and ciprofloxacin in China.
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H? filtering for a class of discrete-time singular Markovian jump systems with time-varying delays.
ISA Trans
PUBLISHED: 03-06-2014
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The problem of H? filtering for a class of discrete-time singular Markovian jump systems with time-varying delays is investigated in this paper. The transition probabilities under consideration are time-varying, i.e., Markovian chain is nonhomogeneous. By using the Lyapunov functional approach and reciprocally convex technique, a less conservative delay-dependent bounded real lemma is developed in terms of linear matrix inequalities. Moreover, a sufficient condition for the existence of the desired filter which guarantees the stochastic admissibility and the H? performance index of the resulting filtering error system is presented. Numerical examples are employed to show the usefulness of the proposed results.
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Screening of hepatocyte proteins binding with the middle surface protein of the hepatitis B virus by the yeast two-hybrid system.
Mol Med Rep
PUBLISHED: 02-20-2014
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The effect of the middle hepatitis B virus surface protein (MHBs) remains to be elucidated. To investigate the biological function of the MHBs protein, the present study performed yeast two-hybrid screening to search for proteins that interact with the MHBs protein in hepatocytes. The bait plasmid expressing the MHBs protein was constructed by cloning the gene of the MHBs protein into pGBKT7, then the recombinant plasmid DNA was transformed into AH109 yeast (a type). The transformed yeast AH109 was mated with yeast Y187 (? type) containing the liver cDNA library plasmid in 2X yeast peptone dextrose adenine (YPDA) medium. The mated diploid yeast was plated on quadruple dropout medium (SD/-Trp-Leu-His-Ade) containing X-?-gal for selection and screening. Following extracting and sequencing of the plasmids from positive (blue) colonies, the sequence analysis was conducted and analyzed by bioinformatics methods. Two colonies were selected and sequenced. Among them, one was the human DNA sequence from the clone RP11-490D19 on chromosome 9 and the other was homo sapiens 12 BAC RP11-180M15 (Roswell Park Cancer Institute Human BAC Library). The yeast two-hybrid system is an effective method for identifying hepatocyte proteins that interact with MHBs. The MHBs protein binds with different proteins suggesting that it has multiple functions in vivo.
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Human heat shock protein 27 exacerbates ischemia reperfusion injury in rats by reducing the number of T regulatory cells.
Mol Med Rep
PUBLISHED: 02-18-2014
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Ischemia reperfusion injury (IRI) occurs in almost every liver surgery and is associated with the reduction of the liver blood flow. Ischemia impairs liver function and can even cause liver failure following surgery. The present study aimed to identify a new molecular target allowing the reduction of IRI and explore the related cellular mechanism. Adenovirus (~2.5x10(12) viral particles) bearing the human heat shock protein 27 (HSP27) gene was injected into rat liver through the ileocecal vein. Five days following the injection, ischemia was induced by clamping the median and left portal veins, hepatic arteries and bile ducts. The levels of alanine transaminase (ALT), aspartate aminotransferase (AST), glutathione (GSH) and superoxide dismutase (SOD) were measured. The infiltration of inflammatory cells and the expression of pro-inflammatory factors were investigated. The number of regulatory T cells (Tregs) was measured by flow cytometry. At 2 h following reperfusion, the group injected with HSP27 had the highest level of ALT and AST, followed by the group injected with HSP27 and treated with gadolinium trichloride (GdCl3), the empty vector-injected and the vector+GdCl3 groups. The HSP27 group also had the lowest levels of the oxidative stress-protective factors SOD and GSH, and the highest levels of pro-inflammatory factors. The number of Tregs was reduced in the groups injected with HSP27. In conclusion, the human HSP27 protein can effectively accelerate liver damage at the early stages of IRI in rats. Tregs might play a critical role in HSP27?induced liver injury.
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Triptolide improves early survival of mesenchymal stem cells transplanted into rat myocardium.
Cardiology
PUBLISHED: 02-18-2014
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To investigate whether triptolide can prolong the survival of rat mesenchymal stem cells (MSCs) transfected with the mouse hyperpolarization-activated cyclic nucleotide-gated channel 4 (mHCN4) gene in the myocardium.
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Three-dimensional visualization of perlecan-rich neoplastic stroma induced concurrently with the invasion of oral squamous cell carcinoma.
J. Oral Pathol. Med.
PUBLISHED: 02-17-2014
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We have demonstrated the induction of perlecan-rich stroma of oral squamous cell carcinoma (SCC) on and after its start of invasion. However, it remains unknown how such a neoplastic stroma is actually arranged in tumor tissues.
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The real-time quantification of autofluorescence spectrum shape for the monitoring of mitochondrial metabolism.
J Biophotonics
PUBLISHED: 02-14-2014
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The cellular proportion of free and protein-bound NADH complexes is increasingly recognized as a metabolic indicator and biomarker. Because free and bound forms exhibit different fluorescence spectra, we consider whether autofluorescence shape sufficiently correlates with mitochondrial metabolism to be useful for monitoring in cellular suspensions. Several computational approaches for rapidly quantifying spectrum shape are used to detect Saccharomyces cereviseae response to oxygenation, and to the addition of mitochondrial functional modifiers and metabolic substrates. Observed changes appear consistent with previous studies probing free/protein-bound proportions, making this a potentially useful approach for the real-time monitoring of metabolism. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).
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Perlecan-enriched intercellular space of junctional epithelium provides primary infrastructure for leukocyte migration through squamous epithelial cells.
Histochem. Cell Biol.
PUBLISHED: 02-09-2014
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The aim of this study was to demonstrate the presence of intraepithelial stroma represented by extracellular matrix (ECM) deposits in the junctional epithelium to clarify its function as a scaffold for leukocyte migration through epithelial cells. Twenty-three biopsy specimens from the gingiva including the junctional epithelium were examined to determine comparative protein and gene level expression profiles for keratin and ECM molecules between the junctional epithelium and the gingival epithelium using immunohistochemistry and in situ hybridization. Intraepithelial leukocyte types and frequencies were also determined and compared between the junctional and gingival epithelia. In the junctional epithelium, which was positive for keratin 19, perlecan was strongly deposited in intercellular space of the whole epithelial layer, while it was faintly positive around the parabasal layer of the gingival epithelium. Perlecan mRNA signals were enhanced to a greater degree in both epithelial and inflammatory cells within the junctional epithelium. In the junctional epithelium, greater numbers of neutrophils and macrophages were found as compared with the gingival epithelium. Our results showed that perlecan is the primary ECM molecule comprising intraepithelial stroma of the junctional epithelium, in which leukocytes may migrate on ECM scaffolds in intercellular space toward the surface of the gingival sulci or pockets.
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MFG-E8 expression for progression of oral squamous cell carcinoma and for self-clearance of apoptotic cells.
Lab. Invest.
PUBLISHED: 01-28-2014
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Milk fat globule-epidermal growth factor (EGF)-factor VIII (MFG-E8) is a secreted glycoprotein that promotes clearance of apoptotic cells by bridging phosphatidylserine on apoptotic cells and integrin ?v?3/5 on phagocytes. High expression of MFG-E8 has been reported in various types of cancer in humans. Apoptotic figures are frequently found in the surgical samples of oral squamous cell carcinoma (SCC) and carcinoma in situ, and we have often observed apoptotic carcinoma cells engulfed by macrophages or even by neighboring carcinoma cells. Thus we hypothesized that MFG-E8 might promote engulfment of apoptotic carcinoma cells by living carcinoma cells and that MFG-E8 expressed by carcinoma cells could contribute to tumor progression. The aim of this study was to elucidate the biological role of MFG-E8 in oral SCC. Fifty-three surgical specimens of oral SCC were used for immunohistochemistry for MFG-E8, and the expression profiles were correlated with clinicopathological properties. Also, we examined the MFG-E8 expression patterns and functions using three human oral SCC cell lines. Most of the cases had MFG-E8-positive SCC cells, and the expression of MFG-E8 was correlated with such clinicopathological features as tumor size, pathological stage, locoregional recurrence, scattering invasion pattern, and SCC cell figures engulfing apoptotic SCC cells. The MFG-E8 staining was enhanced in apoptotic SCC cells, some of which were apparently engulfed by the neighboring SCC cells. ZK-1 cells showed high MFG-E8 expression, and its localization was found in the cytoplasm and the cell surface. Transient MFG-E8 knockdown by siRNA in ZK-1 decreased cell proliferation and invasiveness and increased cell death. Thus we have demonstrated that MFG-E8 promotes tumor progression in oral SCC and that it might be involved in the clearance of apoptotic SCC cells by living SCC cells.
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Optimizing catalysis conditions to decrease aromatic hydrocarbons and increase alkanes for improving jet biofuel quality.
Bioresour. Technol.
PUBLISHED: 01-22-2014
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To produce quality jet biofuel with high amount of alkanes and low amount of aromatic hydrocarbons, two zeolites of HY and HZSM-5 supporting Ni and Mo were used as catalysts to convert soybean oil into jet fuel. Zeolite HY exhibited higher jet range alkane selectivity (40.3%) and lower jet range aromatic hydrocarbon selectivity (23.8%) than zeolite HZSM-5 (13.8% and 58.9%). When reaction temperature increased from 330 to 390°C, yield of jet fuel over Ni-Mo/HY catalyst at 4 MPa hydrogen pressure increased from 0% to 49.1% due to the shift of reaction pathway from oligomerization to cracking reaction. Further increase of reaction temperature from 390 to 410°C resulted in increased yield of jet range aromatic hydrocarbons from 18.7% to 30%, which decreased jet fuel quality. A high yield of jet fuel (48.2%) was obtained at 1 MPa low hydrogen pressure over Ni (8 wt.%)-Mo (12 wt.%)/HY catalyst.
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Microvesicles derived from human Wharton's jelly mesenchymal stem cells promote human renal cancer cell growth and aggressiveness through induction of hepatocyte growth factor.
PLoS ONE
PUBLISHED: 01-01-2014
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In our previous study, microvesicles (MVs) released from human Wharton's jelly mesenchymal stem cells (hWJ-MSCs) retard the growth of bladder cancer cells. We would like to know if MVs have a similar effect on human renal cell carcinoma (RCC). By use of cell culture and the BALB/c nu/nu mice xeno-graft model, the influence of MVs upon the growth and aggressiveness of RCC (786-0) was assessed. Cell counting kit-8 (CCK-8) assay, incidence of tumor, tumor size, Ki-67 or TUNEL staining was used to evaluate tumor cell growth in vitro or in vivo. Flow cytometry assay (in vitro) or examination of cyclin D1 expression (in vivo) was carried out to determine the alteration of cell cycle. The aggressiveness was analyzed by Wound Healing Assay (in vitro) or MMP-2 and MMP-9 expression (in vivo). AKT/p-AKT, ERK1/2/p-ERK1/2 or HGF/c-MET expression was detected by real-time PCR or western blot. Our data demonstrated that MVs promote the growth and aggressiveness of RCC both in vitro and in vivo. In addition, MVs facilitated the progression of cell cycle from G0/1 to S. HGF expression in RCC was greatly induced by MVs, associated with activation of AKT and ERK1/2 signaling pathways. RNase pre-treatment abrogated all effects of MVs. In summary, induction of HGF synthesis via RNA transferred by MVs activating AKT and ERK1/2 signaling is one of crucial contributors to the pro-tumor effect.
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Laboratory diagnosis of avian influenza virus H7N9 infection in a renal transplant recipient.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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A renal transplant recipient who had atypical clinical manifestations, unclear epidemiological exposure history and negative results from influenza virus antigen and nucleic acid amplification in throat swab specimens was admitted into our hospital on April 17, 2013. He was finally diagnosed as avian influenzavirus H7N9 infection. Here, we reviewed the epidemiological, clinical and laboratory findings of this patient. We speculated that the specimens should be collected repeatedly at different sites for suspected cases or special cases needing differential diagnosis; different methods or kits should be used for laboratory testing; atypical clinical manifestations caused by the special nature of patients such as long-term use of immunosuppressive agents and autoimmune diseases should also be taken into account.
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[The clinical patterns and RET proto-oncogene identification of pheochromocytoma in 13 multiple endocrine neoplasia type 2A pedigrees].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 10-31-2013
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To explore the clinical patterns and clinical significance for RET screening in adrenal pheochromocytoma (PHEO) associated with multiple endocrine neoplasia type 2A (MEN2A).
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Automated anterior chamber angle localization and glaucoma type classification in OCT images.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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To identify glaucoma type with OCT (optical coherence tomography) images, we present an image processing and machine learning based framework to localize and classify anterior chamber angle (ACA) accurately and efficiently. In digital OCT photographs, our method automatically localizes the ACA region, which is the primary structural image cue for clinically identifying glaucoma type. Next, visual features are extracted from this region to classify the angle as open angle (OA) or angle-closure (AC). This proposed method has three major contributions that differ from existing methods. First, the ACA localization from OCT images is fully automated and efficient for different ACA configurations. Second, it can directly classify ACA as OA/AC based on only visual features, which is different from previous work for ACA measurement that relies on clinical features. Third, it demonstrates that higher dimensional visual features outperform low dimensional clinical features in terms of angle closure classification accuracy. From tests on a clinical dataset comprising of 2048 images, the proposed method only requires 0.26s per image. The framework achieves a 0.921 ± 0.036 AUC (area under curve) value and 84.0% ± 5.7% balanced accuracy at a 85% specificity, which outperforms existing methods based on clinical features.
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Self-assessment for optic disc segmentation.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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Optic disc segmentation from retinal fundus image is a fundamental but important step in many applications such as automated glaucoma diagnosis. Very often, one method might work well on many images but fail on some other images and it is difficult to have a single method or model to cover all scenarios. Therefore, it is important to combine results from several methods to minimize the risk of failure. For this purpose, this paper computes confidence scores for three methods and combine their results for an optimal one. The experimental results show that the combined result from three methods is better than the results by any individual method. It reduces the mean overlapping error by 7.4% relatively compared with best individual method. Simultaneously, the number of failed cases with large overlapping errors is also greatly reduced. This is important to enhance the clinical deployment of the automated disc segmentation.
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Actin polymerization does not provide direct mechanical forces for vesicle fission during clathrin-mediated endocytosis.
J. Neurosci.
PUBLISHED: 10-04-2013
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Actin polymerization is important for vesicle fission during clathrin-mediated endocytosis (CME), and it has been proposed that actin polymerization may promote vesicle fission during CME by providing direct mechanical forces. However, there is no direct evidence in support of this hypothesis. In the present study, the role of actin polymerization in vesicle fission was tested by analyzing the kinetics of the endocytic tubular membrane neck (the fission-pore) with cell-attached capacitance measurements to detect CME of single vesicles in a millisecond time resolution in mouse chromaffin cells. Inhibition in dynamin GTPase activity increased the fission-pore conductance (Gp), supporting the mechanical role of dynamin GTPase in vesicle fission. However, disruptions in actin polymerization did not alter the fission-pore conductance Gp, thus arguing against the force-generating role of actin polymerization in vesicle fission during CME. Similar to disruptions of actin polymerization, cholesterol depletion results in an increase in the fission-pore duration, indicating a role for cholesterol-dependent membrane reorganization in vesicle fission. Further experiments suggested that actin polymerization and cholesterol might function in vesicle fission during CME in the same pathway. Our results thus support a model in which actin polymerization promotes vesicle fission during CME by inducing cholesterol-dependent membrane reorganization.
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[Effectiveness comparison between endovascular recanalization and open surgical revascularization to treat peripheral pseudoaneurysm].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 09-26-2013
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To compare the effectiveness, complications, and follow-up results between endovascular recanalization (EVR) and open surgical revascularization (OSR) in the treatment of peripheral pseudoaneurysm, so as to provide a reference for choosing a appropriate surgical procedure.
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[Dendritic cell subsets and function in newborns from mothers of different HBV infection status].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
PUBLISHED: 09-19-2013
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The aim of this study was to explore the frequency of mDC and pDC and expression of surface markers of the neonates and to discuss the effect of different status of HBV infection of mother on biological characteristics of DC.
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Biodiesel production from lipids in wet microalgae with microwave irradiation and bio-crude production from algal residue through hydrothermal liquefaction.
Bioresour. Technol.
PUBLISHED: 08-23-2013
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A cogeneration process of biodiesel and bio-crude was proposed to make full use of wet microalgae biomass. High-grade biodiesel was first produced from lipids in wet microalgae through extraction and transesterification with microwave irradiation. Then, low-grade bio-crude was produced from proteins and carbohydrates in the algal residue through hydrothermal liquefaction. The total yield (40.19%) and the total energy recovery (67.73%) of the cogenerated biodiesel and bio-crude were almost equal to those of the bio-oil obtained from raw microalgae through direct hydrothermal liquefaction. Upon microwave irradiation, proteins were partially hydrolyzed and the hydrolysates were apt for deaminization under the hydrothermal condition of the algal residue. Hence, the total remaining nitrogen (16.02%) in the cogenerated biodiesel and bio-crude was lower than that (27.06%) in the bio-oil. The cogeneration process prevented lipids and proteins from reacting to produce low-grade amides and other long-chain nitrogen compounds during the direct hydrothermal liquefaction of microalgae.
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Dynamic microstructures and fractal characterization of cell wall disruption for microwave irradiation-assisted lipid extraction from wet microalgae.
Bioresour. Technol.
PUBLISHED: 08-18-2013
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To extract lipids from wet microalgae through cell disruption, the effects of microwave treatment on the dynamic cell wall microstructures were investigated. The fractal dimension of raw, untreated microalgal cells was 1.46. The disruption level of microalgal cell walls was enhanced when microwave treatment temperature increased from 80 to 120°C, resulting in an increase in microalgal cell fractal dimension from 1.61 to 1.91. The cell wall thickness and pore diameters in cell walls increased from 0.11 to 0.59?m and from 0.005 to 0.18?m, respectively, when microwave treatment time increased from 0 to 20min. The outer pectin layers of cell walls gradually detached and the porosity of inner cellulose layers increased when microwave treatment time increased to 26min. The initial point of disruption appeared at the maximum curvature (approximately 1.01×10(7)m(-1)) of cell walls. Numbers of short-chain and saturated lipids increased because of microwave electromagnetic effect.
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IP3 decreases coronary artery tone via activating the BKCa channel of coronary artery smooth muscle cells in pigs.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-13-2013
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Large conductance Ca(2+)-activated K(+) channel (BKCa) is a potential target for coronary artery-relaxing medication, but its functional regulation is largely unknown. Here, we report that inositol trisphosphate (IP3) activated BKCa channels in isolated porcine coronary artery smooth muscle cells and by which decreased the coronary artery tone. Both endogenous and exogenous IP3 increased the spontaneous transient outward K(+) currents (STOC, a component pattern of BKCa currents) in perforated and regular whole-cell recordings, which was dependent on the activity of IP3 receptors. IP3 also increased the macroscopic currents (MC, another component pattern of BKCa currents) via an IP3 receptor- and sarcoplasmic Ca(2+) mobilization-independent pathway. In inside-out patch recordings, direct application of IP3 to the cytosolic side increased the open probability of single BKCa channel in an IP3 receptor-independent manner. We conclude that IP3 is an activator of BKCa channels in porcine coronary smooth muscle cells and exerts a coronary artery-relaxing effect. The activation of BKCa channels by IP3 involves the enhancement of STOCs via IP3 receptors and stimulation of MC by increasing the Ca(2+) sensitivity of the channels.
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Targeting proximal tubule mitochondrial dysfunction attenuates the renal disease of methylmalonic acidemia.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-29-2013
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Isolated methylmalonic acidemia (MMA), caused by deficiency of the mitochondrial enzyme methylmalonyl-CoA mutase (MUT), is often complicated by end stage renal disease that is resistant to conventional therapies, including liver transplantation. To establish a viable model of MMA renal disease, Mut was expressed in the liver of Mut(-/-) mice as a stable transgene under the control of an albumin (INS-Alb-Mut) promoter. Mut(-/-);Tg(INS-Alb-Mut) mice, although completely rescued from neonatal lethality that was displayed by Mut(-/-) mice, manifested a decreased glomerular filtration rate (GFR), chronic tubulointerstitial nephritis and ultrastructural changes in the proximal tubule mitochondria associated with aberrant tubular function, as demonstrated by single-nephron GFR studies. Microarray analysis of Mut(-/-);Tg(INS-Alb-Mut) kidneys identified numerous biomarkers, including lipocalin-2, which was then used to monitor the response of the GFR to antioxidant therapy in the mouse model. Renal biopsies and biomarker analysis from a large and diverse patient cohort (ClinicalTrials.gov identifier: NCT00078078) precisely replicated the findings in the animals, establishing Mut(-/-);Tg(INS-Alb-Mut) mice as a unique model of MMA renal disease. Our studies suggest proximal tubular mitochondrial dysfunction is a key pathogenic mechanism of MMA-associated kidney disease, identify lipocalin-2 as a biomarker of increased oxidative stress in the renal tubule, and demonstrate that antioxidants can attenuate the renal disease of MMA.
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Hybrid ameloblastoma and adenomatoid odontogenic tumor: report of a case and review of hybrid variations in the literature.
Oral Surg Oral Med Oral Pathol Oral Radiol
PUBLISHED: 07-03-2013
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Hybrid odontogenic tumors including 2 or more different histologic types have been documented, but their occurrences are not very common. We present a case of hybrid odontogenic tumor composed of ameloblastoma and adenomatoid odontogenic tumor (AOT) arising in the mandibular molar region of a 31-year-old Japanese woman who had a history of familial adenomatous polyposis. The tumor, measuring 10 mm in diameter, was surgically removed from the alveolar bone. Histopathologically, the tumor consisted of both follicular and plexiform types of ameloblastoma in which multiple and smaller foci of AOT were intermingled. There have been 3 reported cases of hybrid ameloblastoma and AOT, all of which presented unicystic types as ameloblastoma components. This, however, is the first report of a hybrid tumor containing an authentic solid-type ameloblastoma compartment and an AOT compartment in a patient with a background of familial adenomatous polyposis.
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Finite-time H? control for a class of Markovian jump systems with mode-dependent time-varying delays via new Lyapunov functionals.
ISA Trans
PUBLISHED: 06-20-2013
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This paper is concerned with the problem of finite-time H? control for a class of Markovian jump systems with mode-dependent time-varying delays via new Lyapunov functionals. In order to reduce conservatism, a new Lyapunov-Krasovskii functional is constructed. Based on the derived condition, the reliable H? control problem is solved, and the system trajectory stays within a prescribed bound during a specified time interval. Finally, numerical examples are given to demonstrate the proposed approach is more effective than some existing ones.
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Improvement of the energy conversion efficiency of Chlorella pyrenoidosa biomass by a three-stage process comprising dark fermentation, photofermentation, and methanogenesis.
Bioresour. Technol.
PUBLISHED: 06-18-2013
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The effects of pre-treatment methods on saccharification and hydrogen fermentation of Chlorella pyrenoidosa biomass were investigated. When raw biomass and biomass pre-treated by steam heating, by microwave heating, and by ultrasonication were used as feedstock, the hydrogen yields were only 8.8-12.7 ml/g total volatile solids (TVS) during dark fermentation. When biomass was pre-treated by steam heating with diluted acid and by microwave heating with diluted acid, the dark hydrogen yields significantly increased to 75.6 ml/g TVS and 83.3 ml/g TVS, respectively. Steam heating with diluted acid is the preferred pre-treatment method of C. pyrenoidosa biomass to improve hydrogen yield during dark fermentation and photofermentation, which is followed by methanogenesis to increase energy conversion efficiency (ECE). A total hydrogen yield of 198.3 ml/g TVS and a methane yield of 186.2 ml/g TVS corresponding to an overall ECE of 34.0% were obtained through the three-stage process (dark fermentation, photofermentation, and methanogenesis).
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[Analysis on the spatial clustering of tuberculosis based on provincial level in China from 2008 to 2010].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 06-12-2013
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To study the tuberculosis clustering areas and the changing trend, from 2008 to 2010, so as to provider the reference for tuberculosis control.
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The effect of donor-recipient gender mismatch on short- and long-term graft survival in kidney transplantation: a systematic review and meta-analysis.
Clin Transplant
PUBLISHED: 06-10-2013
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There is no limitation of gender matching in renal transplantation. This study was intended to evaluate its effect on short- and long-term graft survival.
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The Up-Regulation of Histone Deacetylase 8 Promotes Proliferation and Inhibits Apoptosis in Hepatocellular Carcinoma.
Dig. Dis. Sci.
PUBLISHED: 06-06-2013
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Histone deacetylase 8 (HDAC8), a member of class I HDACs, has been reported to be involved in transcriptional regulation, cell cycle progression, and developmental events, and several studies have shown that HDAC8 plays a critical role in tumorigenesis. However, the expression level and the potential role of HDAC8 in hepatocellular carcinoma (HCC) remain unclear.
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Microarray analysis of microRNA expression in peripheral blood mononuclear cells of critically ill patients with influenza A (H1N1).
BMC Infect. Dis.
PUBLISHED: 05-30-2013
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With concerns about the disastrous health and economic consequences caused by the influenza pandemic, comprehensively understanding the global host response to influenza virus infection is urgent. The role of microRNA (miRNA) has recently been highlighted in pathogen-host interactions. However, the precise role of miRNAs in the pathogenesis of influenza virus infection in humans, especially in critically ill patients is still unclear.
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Epidemiological survey and risk factor analysis of fatty liver disease of adult residents, Beijing, China.
J. Gastroenterol. Hepatol.
PUBLISHED: 05-18-2013
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With the changes in diet structure and lifestyle, the incidence of fatty liver disease is increasing in China, especially in cities. The goal of the present study was to accurately determine the prevalence and risk factors of fatty liver disease in Beijing residents, China.
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MicroRNA-503 inhibits the G1/S transition by downregulating cyclin D3 and E2F3 in hepatocellular carcinoma.
J Transl Med
PUBLISHED: 05-13-2013
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Increasing evidence indicates that deregulation of microRNAs (miRNAs) is involved in tumorigenesis. Downregulation of microRNA-503 has been observed in various types of diseases, including cancer. However, the biological function of miR-503 in hepatocellular carcinoma (HCC) is still largely unknown. In this study we aimed to elucidate the prognostic implications of miR-503 in HCC and its pathophysiologic role.
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Improving CO2 fixation efficiency by optimizing Chlorella PY-ZU1 culture conditions in sequential bioreactors.
Bioresour. Technol.
PUBLISHED: 05-09-2013
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To fix CO2 emissions efficiently from flue gas of coal-fired power plants, the culture medium, light intensity and bioreactors were comprehensively optimized in the process of CO2 fixation by Chlorella PY-ZU1. To make up for relative insufficiency of nutrients (except for the carbon source) resulting from continuous bubbling of 15% CO2, three chemicals were added into the culture to optimize the molar ratios of nitrogen to carbon, phosphorus to carbon, and magnesium to carbon in culture from 0.17 to 0.69, from 0.093 to 0.096, and from 0.018 to 0.030, respectively. Such adjustments led to a 1.25-fold increase in biomass (from 2.41 to 5.42 g L(-1)). By enhancing light intensity from 4500 to 6000 lux, the peak growth rate of Chlorella PY-ZU1 increased by 99% and reached to 0.95 g L(-1) day(-1). Use of a multi-stage sequential bioreactor notably improved the peak CO2 fixation efficiency to 85.6%.
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Risk factors associated with the occurrence of silent pulmonary embolism in patients with deep venous thrombosis of the lower limb.
Phlebology
PUBLISHED: 05-09-2013
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OBJECTIVE: The aim of our study is to investigate the prevalence of silent pulmonary embolism in patients with deep venous thrombosis in the lower limbs and to evaluate the associated risk factors. METHODS: A total of 322 patients with acute deep venous thrombosis confirmed by CT venography or Doppler ultrasonography were studied. The diagnosis of silent pulmonary embolism was established by computed tomography pulmonary arteriography (CTPA). The association between covariates and the prevalence of silent pulmonary embolism in patients with deep venous thrombosis in lower limbs were assessed using chi-square test and multivariable regression. RESULTS: The incidence of silent pulmonary embolism was 33.5% (108 in 322 patients) in all patients with deep venous thrombosis in lower limbs. Chi-square test showed male gender, the right lower limb, proximal location of the thrombus, unprovoked venous thrombosis and coexisting heart diseases were related to a higher incidence of silent pulmonary embolism in patients with deep venous thrombosis in lower limbs. The multivariate regression analysis confirmed that the risk factors associated with silent pulmonary embolism in deep venous thrombosis patients included the right side and proximal location of the thrombus (odds ratio: 2.023, 95% CI: 1.215-3.368; odds ratio: 3.610, 95% CI: 1.772-7.354), unprovoked venous thrombosis (odds ratio: 2.037, 95% CI: 1.188-3.493), coexisting heart diseases (odds ratio: 4.507, 95% CI: 2.667-7.618). CONCLUSION: Silent pulmonary embolism occurred frequently in patients with deep venous thrombosis in lower limbs. The right side, the proximal location of the thrombus, unprovoked venous thrombosis and coexisting heart diseases increased the risk for the occurrence of silent pulmonary embolism.
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Comparative study of the mutant prevention concentrations of vancomycin alone and in combination with levofloxacin, rifampicin and fosfomycin against methicillin-resistant Staphylococcus epidermidis.
J. Antibiot.
PUBLISHED: 05-08-2013
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No mutant-prevention concentration (MPC) with methicillin-resistant Staphylococcus epidermidis (MRSE) has been reported. The study aimed to evaluate the propensity of vancomycin individually and in combination to prevent MRSE from mutation. A total of 10 MRSE clinical isolates were included in the study. Susceptibility testing demonstrated that the susceptibility rates to vancomycin, rifampicin, levofloxacin and fosfomycin were 100, 100, 50 and 90%, respectively. The fractional inhibition concentration indices (FICI) for vancomycin combined with rifampicin, levofloxacin or fosfomycin were ?1.5 but ?2, ?1.5 but ?2, and >0.5 but ?1.5, respectively, implying indifferent interactivity. The MPC with susceptible strains was determined to be the lowest antibiotic concentration inhibiting visible growth among 10(10) CFU on four agar plates (9?cm in diameter) after a 72-h incubation at 37?°C. The MPCs were 16?32, >64, ?64 and 4?16??g?ml(-1) for vancomycin, rifampicin, fosfomycin and levofloxacin, respectively. The vancomycin MPCs of combinations with fosfomycin (32??g?ml(-1)), levofloxacin (2??g?ml(-1)) and rifampicin (2 or 4??g?ml(-1)) were 1?4, 16?32 and 16?32??g?ml(-1), respectively. Against mutants selected by vancomycin, rifampicin, levofloxacin and fosfomycin individually, antibiotics had standard MICs of 2?4??g?ml(-1) for vancomycin, >64??g?ml(-1) for rifampicin, 4?8??g?ml(-1) for levofloxacin and ?64??g?ml(-1) for fosfomycin. Thus single-step mutation can lead to resistance of MRSE to rifampicin, levofloxacin and fosfomycin, rather than non-susceptibility to vancomycin. Vancomycin-fosfomycin combination might be a superior alternative to vancomycin in blocking the growth of MRSE mutants, especially for high-organism-burden infections.
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Methylation of nucleolar and coiled-body phosphoprotein 1 is associated with the mechanism of tumorigenesis in hepatocellular carcinoma.
Oncol. Rep.
PUBLISHED: 04-26-2013
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Nucleolar and coiled-body phosphoprotein 1 (NOLC1) plays an essential role in the synthesis of rRNA and the biosynthesis of ribosomes. Previous studies suggest that NOLC1 is crucial for normal cell growth, and plays a role in the regulation of tumorigenesis of nasopharyngeal carcinoma (NPC) and demonstrate that both NOLC1 and tumor protein 53 work synergistically to activate the MDM2 promoter in NPC cells. Yet, the functioning of NOLC1 in liver cancer remains unknown. The aim of the present study was to understand how the NOLC1 gene is regulated in liver carcinogenesis. In this study, we showed that NOLC1 was silenced or downregulated in liver tumor tissues when compared with that in the matched non-cancer tissues. In addition, human hepatoma cells weakly expressed NOLC1, whereas cultured human normal liver cell lines expressed abundant levels. The hypermethylation status in the promoter CpG1 start region appeared to be correlated with the NOLC1 expression levels in liver cell lines or liver normal and tissue specimens. We found that four CpG dinucleotides were located at the CpG1 start region. Further molecular analysis of mutagenesis indicated that the four CpG dinucleotides play a role in the promoter activity of the NOLC1 gene. The expression of NOLC1 and DNA methylation of its promoter affected cell proliferation and apoptosis. The expression of NOLC1 in hepatoma cell lines was restored following exposure to the demethylation agent, 5-azacytidine. Low expression of NOLC1 in hepatoma cell lines and liver cancer tissues was associated with cyclin D3. In conclusion, our study demonstrated that DNA methylation is a key mechanism of silenced NOLC1 expression in human hepatocellular carcinoma cells, and NOLC1 gene hypermethylation of the four CpG dinucleotides is a potential biomarker for hepatocellular carcinoma.
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Deep RNA-Seq uncovers the peach transcriptome landscape.
Plant Mol. Biol.
PUBLISHED: 04-15-2013
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Peach (Prunus persica) is one of the most important of deciduous fruit trees worldwide. To facilitate isolation of genes controlling important horticultural traits of peach, transcriptome sequencing was conducted in this study. A total of 133 million pair-end RNA-Seq reads were generated from leaf, flower, and fruit, and 90 % of reads were mapped to the peach draft genome. Sequence assembly revealed 1,162 transcription factors and 2,140 novel transcribed regions (NTRs). Of these 2,140 NTRs, 723 contain an open reading frame, while the rest 1,417 are non-coding RNAs. A total of 9,587 SNPs were identified across six peach genotypes, with an average density of one SNP per ~5.7 kb. The top of chromosome 2 has higher density of expressed SNPs than the rest of the peach genome. The average density of SSR is 312.5/Mb, with tri-nucleotide repeats being the most abundant. Most of the detected SSRs are AT-rich repeats and the most common di-nucleotide repeat is CT/TC. The predominant type of alternative splicing (AS) events in peach is exon-skipping isoforms, which account for 43 % of all the observed AS events. In addition, the most active transcribed regions in peach genome were also analyzed. Our study reveals for the first time the complexity of the peach transcriptome, and our results will be helpful for functional genomics research in peach.
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Intramuscular keratocyst as a soft tissue counterpart of keratocystic odontogenic tumor: differential diagnosis by immunohistochemistry.
Hum. Pathol.
PUBLISHED: 04-12-2013
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Keratocystic odontogenic tumor (KCOT), a developmental jaw cyst previously referred to as odontogenic keratocyst (OKC), typically arises in the jawbone. In this article, however, we report a case of KCOT located within the temporalis muscle. We compared its immunohistochemical profiles with those of authentic jaw KCOT, orthokeratinized odontogenic cyst, and epidermoid cyst in order to consider whether a soft tissue counterpart of KCOT could be a separate disease entity. The patient was a 46-year-old man with a well-defined cystic lesion within the left temporalis muscle. On computed tomographic images, the lesion was recognized as a cystic lesion, although KCOT was not included in the clinical differential diagnoses. The location of the lesion was not within bone but, rather, within the temporalis muscle that was attached to the jawbones. Our review of the literature has disclosed more than 20 peripheral KCOT cases of the oral mucosa and more than 10 cases of the skin, but only 1 case arising in muscle. Immunohistochemical investigation of the present intramuscular case reveals KCOT-characteristic profiles distinct from the other 3 types of cysts investigated. The results indicate that KCOT-like lesions can arise within soft tissues, although use of the term odontogenic might seem inappropriate in those cases.
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MAPK Signal Transduction Pathway Regulation: A Novel Mechanism of Rat HSC-T6 Cell Apoptosis Induced by FUZHENGHUAYU Tablet.
Evid Based Complement Alternat Med
PUBLISHED: 04-09-2013
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FUZHENGHUAYU Tablets have been widely used in the treatment of liver fibrosis in China. Here, we investigate the apoptotic effect of FUZHENGHUAYU Tablet in rat liver stellate cell line HSC-T6. HSC-T6 cells were incubated with control serum or drug serum from rats fed with 0.9% NaCl or FUZHENGHUAYU Tablet, respectively. Cells exposed to drug serum showed higher proportions of early and late apoptotic cells than controls. The mRNA levels of collagens I and III, TGF-?1 and ?-SMA were reduced by drug serum compared to control serum. Differentially expressed mRNAs and miRNAs were analyzed by microarray and sequencing, respectively. We identified 334 differentially expressed mRNAs and also 60?GOs and two pathways related to the mRNAs. Seventy-five differentially expressed miRNAs were down-regulated by drug serum and 1963 target genes were predicted. 134 GOs up-regulated in drug serum group were linked to miRNA targets, and drug serum also regulated 43 miRNA signal transduction pathways. Protein levels were evaluated by Western blot. Drug serum down-regulated (phospho-SAPK/JNK)/(SAPK/JNK) and up-regulated phospho-p38/p38 ratios. The study showed that FUZHENGHUAYU Tablet induced apoptosis in rat HSC-T6 cells possibly in part by activating p38 and inhibiting SAPK/JNK.
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Origin of additional capacities in metal oxide lithium-ion battery electrodes.
Nat Mater
PUBLISHED: 04-03-2013
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Metal fluorides/oxides (MFx/MxOy) are promising electrodes for lithium-ion batteries that operate through conversion reactions. These reactions are associated with much higher energy densities than intercalation reactions. The fluorides/oxides also exhibit additional reversible capacity beyond their theoretical capacity through mechanisms that are still poorly understood, in part owing to the difficulty in characterizing structure at the nanoscale, particularly at buried interfaces. This study employs high-resolution multinuclear/multidimensional solid-state NMR techniques, with in situ synchrotron-based techniques, to study the prototype conversion material RuO2. The experiments, together with theoretical calculations, show that a major contribution to the extra capacity in this system is due to the generation of LiOH and its subsequent reversible reaction with Li to form Li2O and LiH. The research demonstrates a protocol for studying the structure and spatial proximities of nanostructures formed in this system, including the amorphous solid electrolyte interphase that grows on battery electrodes.
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Intrahepatic cholestasis in common chronic liver diseases.
Eur. J. Clin. Invest.
PUBLISHED: 03-12-2013
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Cholestasis represents the consequence of impaired bile formation and decrease in bile flow, generally classified as extra- and intrahepatic. Cholestasis is the pivotal hallmark of the so-called primary cholestatic liver diseases but may also emerge in other forms of chronic liver injury. The aim now was to summarise the current state of knowledge on intrahepatic cholestasis related to chronic liver diseases.
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Podoplanin-mediated cell adhesion through extracellular matrix in oral squamous cell carcinoma.
Lab. Invest.
PUBLISHED: 02-21-2013
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Podoplanin (PDPN), one of the representative mucin-like type-I transmembrane glycoproteins specific to lymphatic endothelial cells, is expressed in various cancers including squamous cell carcinoma (SCC). On the basis of our previous studies, we have developed the hypothesis that PDPN functions in association with the extracellular matrix (ECM) from the cell surface side. The aim of this study was to elucidate the molecular role of PDPN in terms of cell adhesion, proliferation, and migration in oral SCC cells. Forty-four surgical specimens of oral SCC were used for immunohistochemistry for PDPN, and the expression profiles were correlated with their clinicopathological properties. Using ZK-1, a human oral SCC cell system, and five other cell systems, we examined PDPN expression levels by immunofluorescence, western blotting, and real-time PCR. The effects of transient PDPN knockdown by siRNA in ZK-1 were determined for cellular functions in terms of cell proliferation, adhesion, migration, and invasion in association with CD44 and hyaluronan. Cases without PDPN-positive cells were histopathologically classified as less-differentiated SCC, and SCC cells without PDPN more frequently invaded lymphatics. Adhesive properties of ZK-1 were significantly inhibited by siRNA, and PDPN was shown to collaborate with CD44 in cell adhesion to tether SCC cells with hyaluronan-rich ECM of the narrow intercellular space as well as with the stromal ECM. There was no siRNA effect in migration. We have demonstrated the primary function of PDPN in cell adhesion to ECM, which is to secondarily promote oral SCC cell proliferation.
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In situ investigation of allografted mouse HCN4 gene-transfected rat bone marrow mesenchymal stromal cells with the use of patch-clamp recording of ventricular slices.
Cytotherapy
PUBLISHED: 02-21-2013
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Recently, proof-of-concept experiments have shown that genetically modified bone marrow mesenchymal stromal cells (MSCs) carrying hyperpolarization-activated cyclic nucleotide-gated (HCN) channels were able to express the funny current (If) in vitro, which played a key role in the process of pacemaker generation for heart rate, and were capable of pacemaker function after transplantation into the host heart. Nevertheless, because of the lack of direct experimental access to the implanted cells in situ, the changes in electrophysiological characteristics and the mechanisms underlying the pacemaker function of engrafted HCN gene-transfected MSCs in vivo remain unclear.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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