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Find video protocols related to scientific articles indexed in Pubmed.
Absolute distance measurement by intensity detection using a mode-locked femtosecond pulse laser.
Opt Express
PUBLISHED: 06-13-2014
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We propose an interferometric method that enables to measure a distance by the intensity measurement using the scanning of the interferometer reference arm and the recording of the interference fringes including the brightest fringe. With the consideration of the dispersion and absorption of the pulse laser in a dispersive and absorptive medium, we investigate the cross-correlation function between two femtosecond laser pulses in the time domain. We also introduce the measurement principle. We study the relationship between the position of the brightest fringe and the distance measured, which can contribute to the distance measurement. In the experiments, we measure distances using the method of the intensity detection while the reference arm of Michelson interferometer is scanned and the fringes including the brightest fringe is recorded. Firstly we measure a distance in a range of 10 µm. The experimental results show that the maximum deviation is 45 nm with the method of light intensity detection. Secondly, an interference system using three Michelson interferometers is developed, which combines the methods of light intensity detection and time-of-flight. This system can extend the non-ambiguity range of the method of light intensity detection. We can determine a distance uniquely with a larger non-ambiguity range. It is shown that this method and system can realize absolute distance measurement, and the measurement range is a few micrometers in the vicinity of Nl(pp), where N is an integer, and lpp is the pulse-to-pulse length.
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A magnetically separable photocatalyst based on nest-like ?-Fe?O?/ZnO double-shelled hollow structures with enhanced photocatalytic activity.
Nanoscale
PUBLISHED: 11-09-2011
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Magnetic nest-like ?-Fe(2)O(3)/ZnO double-shelled hollow nanostructures have been successfully synthesized via a multi-step process. The materials have been thoroughly characterized by different techniques. These interesting nest-like hollow nanostructures are composed of ZnO nanoflakes grown on the surface of ?-Fe(2)O(3) hollow spheres. Importantly, these magnetic hollow nanostructures show very high visible-light photocatalytic activity for the degradation of different organic dyes including methylene blue (MB), Rhodamine-B (RhB), and methyl orange (MO). It is further demonstrated that these ?-Fe(2)O(3)/ZnO hybrid photocatalysts are highly stable and can be used repeatedly.
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Resequencing 50 accessions of cultivated and wild rice yields markers for identifying agronomically important genes.
Nat. Biotechnol.
PUBLISHED: 06-03-2011
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Rice is a staple crop that has undergone substantial phenotypic and physiological changes during domestication. Here we resequenced the genomes of 40 cultivated accessions selected from the major groups of rice and 10 accessions of their wild progenitors (Oryza rufipogon and Oryza nivara) to >15 × raw data coverage. We investigated genome-wide variation patterns in rice and obtained 6.5 million high-quality single nucleotide polymorphisms (SNPs) after excluding sites with missing data in any accession. Using these population SNP data, we identified thousands of genes with significantly lower diversity in cultivated but not wild rice, which represent candidate regions selected during domestication. Some of these variants are associated with important biological features, whereas others have yet to be functionally characterized. The molecular markers we have identified should be valuable for breeding and for identifying agronomically important genes in rice.
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Simvastatin augments the efficacy of therapeutic angiogenesis induced by bone marrow-derived mesenchymal stem cells in a murine model of hindlimb ischemia.
Mol. Biol. Rep.
PUBLISHED: 04-23-2011
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Many studies showed beneficial effects of either statin or bone marrow-derived mesenchymal stem cells (MSC) treatment in ischemic disease. In an attempt to further improve postischemic tissue repair, we investigated the effect of a local administration of MSC, in the presence or not of low-dose simvastatin, on angiogenesis and functional recovery in a mouse model of hindlimb ischemia. In vitro, the proliferation, migration, apoptosis, and tube formation of bone marrow MSC derived from transgenic mice expressing green fluorescent protein (GFP) were detected in the presence or not of 0.01 ?mol/l simvastatin, respectively. In vivo, immediately after hindlimb ischemia, the mice were divided into four groups, namely control, MSC, statin, and statin-MSC, and received a single local injection of MSC (2×10(6) cells) and/or a repeated gavages administration of simvastatin (0.2 mg/kg) for 21 days. The blood flow was measured by laser Doppler imaging, the capillary density was detected by alkaline phosphatase staining and, the MSC differentiation was assessed by immunofluorescent staining at 21 days after the ischemia. In vitro, the MSC proliferation rate, migration ability and tube formation number were increased significantly in simvastatin group relative to control group. Whereas, the H2O2 induced-apoptosis was inhibited significantly in simvastatin group relative to control group. In vivo, hindlimb blood reperfusion was significantly improved (MSC 0.55±0.08, statin 0.57±0.05, vs. control 0.47±0.07, P<0.05) and capillary density was obviously higher at day 21 post-ischemia by Laser Doppler Imaging in the MSC group and the Statin group when compared with control group. The combined use of statin and MSC further improved revascularization (perfusion ratio of 0.70±0.09; P<0.001 verse other groups) and resulted in the highest capillary density (P<0.05 vs. all other groups). GFP-labeled transplanted cells were more frequently observed in the Statin-MSC group than in the MSC group (6.8±0.5-3.1±0.7, P<0.05). Low-dose simvastatin could act in a synergistic way with MSC to potentiate the functional neovascularization in a mouse model of hind limb ischemia.
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Zinc supplementation results in improved therapeutic potential of bone marrow-derived mesenchymal stromal cells in a mouse ischemic limb model.
Cytotherapy
PUBLISHED: 09-15-2010
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We wanted to determine whether zinc supplementation can inhibit bone marrow-derived mesenchymal stromal cell (MSC) apoptosis and enhance their tissue regenerative potential a in mouse ischemic hindlimb model.
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Augmentation of neovascularization in murine hindlimb ischemia by combined therapy with simvastatin and bone marrow-derived mesenchymal stem cells transplantation.
J. Biomed. Sci.
PUBLISHED: 07-11-2010
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We postulated that combining high-dose simvastatin with bone marrow derived-mesenchymal stem cells (MSCs) delivery may give better prognosis in a mouse hindlimb ischemia model.
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A novel approach to transplanting bone marrow stem cells to repair human myocardial infarction: delivery via a noninfarct-relative artery.
Cardiovasc Ther
PUBLISHED: 03-27-2010
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Bone marrow stem cells are able to repair infarcted human myocardium following intracoronary transplantation via the infarct-relative artery. However, traditional reperfusion strategies fail to open the artery in some patients, making effective delivery impossible. Our previous study demonstrated a safe and efficient approach to delivering bone marrow stem cells via a noninfarcted artery in an animal myocardial infarction model. The objective of the present study was to evaluate the safety and feasibility of autologous bone marrow mesenchymal stem cell transplantation via such an approach in patients with acute myocardial infarction (AMI). Sixteen patients with anterior AMI who had successfully undergone percutaneous coronary intervention (PCI) were enrolled in this pilot, randomized study. Three weeks after PCI, cultured bone marrow mesenchymal stem cells were injected into the myocardium via either the infarct-relative artery (left anterior descending branch artery, LAD) or a noninfarct-relative artery (right coronary artery, RCA). The safety and feasibility of the cell infusion were evaluated during the procedure and during 6 months of follow-up. In addition, 2D echocardiography, technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) and 18F-deoxyglucose single photon emission computed tomography were employed to examine cardiac function, myocardial perfusion, and viable cardiomyocytes, respectively, at day 4 after PCI and 6 months after the cell infusion. There were no arrhythmia and any other side-effects, including infections, allergic reactions or adverse clinical events, during, immediately after, or 6 months after cell transplantation. Cardiac function and myocardial perfusion had improved 6 months after PCI/bone marrow stem cells transplantation. Viable cardiomyocytes metabolism was detected in the infarcted areas in both groups after the cell infusion, as demonstrated by 18F-deoxyglucose. Intracoronary infusion of autologous bone marrow mesenchymal stem cells via a noninfarct-relative artery appears safe and feasible in the treatment of patients with AMI.
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Immediate and long-term results of coronary angioplasty in patients aged 80 years and older.
Cardiol Res Pract
PUBLISHED: 03-10-2010
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Objectives. To observe the short- and long-term outcomes after percutaneous coronary intervention (PCI) in octogenarians (>80 y.o.) at our institution. Method. All octogenarians who underwent PCI during the study period were retrospectively retrieved from our database and clinically followed. Major adverse cardiac (and cerebral) events (MAC(C)E) was considered as primary outcome. Results. From January 2003 to December 2007, 140 octogenarians (mean age: 85+/-3 y.o., 79% of male) underwent PCI and were clinically followed 14+/-11 months. Procedural success was obtained in 100 percent of patients with single vessel disease, in 96 percent of patients with double vessel disease, and in 75 percent of patients with triple vessel disease. In-hospital, 30 days, and one year MACE rates were 5%, 5%, and 10.7%, respectively. Impaired left ventricular (LV) ejection fraction (hazard ratio (HR) = 0.909, 95% confidence interval (CI) = 0.856 to 0.964, P = .002), diabetes mellitus (HR = 5.792, 95% CI = 1.785 to 18.796, P = .003), and low GFR (HR = 2.943, 95% CI = 1.161, to 7.464, P = .023) were independently associated with an increase risk of MACE at long-term followup. Conclusion. Coronary angiography can be successfully performed in elderly patients with single and double vessel disease. The results in triple vessel disease are encouraging. Low LV function, diabetes, and impaired renal function increase the risk of long-term major adverse cardiac events.
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Lipopolysaccharide preconditioning enhances the efficacy of mesenchymal stem cells transplantation in a rat model of acute myocardial infarction.
J. Biomed. Sci.
PUBLISHED: 06-08-2009
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Mesenchymal stem cells (MSCs)-based regenerative therapy is currently regarded as an alternative approach to salvage the acute myocardial infarcted hearts. However, the efficiency of MSCs transplantation is limited by lower survival rate of engrafted MSCs. In previous study, we found that 1.0 microg/ml Lipopolysaccharide (LPS) could protect MSCs against apoptosis induced by oxidative stress and meanwhile enhance the proliferation of MSCs. Therefore, in the present study, we firstly preconditioned MSCs with 1.0 microg/ml LPS, then transplanted MSCs into ischemic myocardium, and observed the survival and cardiac protective capacity of MSCs in a rat model of acute myocardial infarction. Furthermore, we tried to explore the underlying mechanisms and the role of Toll-like receptor-4 (TLR4) in the signal pathway of LPS-induced cardiac protection.
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An automated inner dimensional measurement system based on a laser displacement sensor for long-stepped pipes.
Sensors (Basel)
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A novel measurement prototype based on a mobile vehicle that carries a laser scanning sensor is proposed. The prototype is intended for the automated measurement of the interior 3D geometry of large-diameter long-stepped pipes. The laser displacement sensor, which has a small measurement range, is mounted on an extended arm of known length. It is scanned to improve the measurement accuracy for large-sized pipes. A fixing mechanism based on two sections is designed to ensure that the stepped pipe is concentric with the axis of rotation of the system. Data are acquired in a cylindrical coordinate system and fitted in a circle to determine diameter. Systematic errors covering arm length, tilt, and offset errors are analyzed and calibrated. The proposed system is applied to sample parts and the results are discussed to verify its effectiveness. This technique measures a diameter of 600 mm with an uncertainty of 0.02 mm at a 95% confidence probability. A repeatability test is performed to examine precision, which is 1.1 ?m. A laser tracker is used to verify the measurement accuracy of the system, which is evaluated as 9 ?m within a diameter of 600 mm.
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MTHFR C677T and MTR A2756G polymorphisms and the homocysteine lowering efficacy of different doses of folic acid in hypertensive Chinese adults.
Nutr J
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This study aimed to investigate if the homocysteine-lowering efficacy of two commonly used physiological doses (0.4 mg/d and 0.8 mg/d) of folic acid (FA) can be modified by individual methylenetetrahydrofolate reductase (MTHFR) C677T and/or methionine synthase (MTR) A2756G polymorphisms in hypertensive Chinese adults.
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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.