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Find video protocols related to scientific articles indexed in Pubmed.
Efficacy of hemostatic matrix and microporous polysaccharide hemospheres.
J. Surg. Res.
PUBLISHED: 02-25-2014
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Microporous Polysaccharide Hemospheres (MPH) are a new plant-derived polysaccharide powder hemostat. Previous studies investigated MPH as a replacement to nonflowable hemostatic agents of different application techniques (e.g., oxidized cellulose, collagen); therefore, the purpose of this study was to determine if MPH is a surrogate for flowable hemostatic agents of similar handling and application techniques, specifically a flowable thrombin-gelatin hemostatic matrix.
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Printable highly catalytic Pt- and TCO-free counter electrode for dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 02-05-2014
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Here we show that a counter electrode based on carbon network supported Cu2ZnSnS4 nanodots on Mo-coated soda-lime glass for dye-sensitized solar cells can outperform the conventional best electrode with Pt nanoparticles on the fluorine-doped SnO2 conducting glass. In the as-developed electrode, all of the elements are of high abundance ratios with low materials cost. The fabrication is scalable because it is conducted by a screen-printing based approach. Therefore, this research lays a solid ground for the large area fabrication of high-performance dye-sensitized solar cell at reduced material cost.
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Few-layer MoSe? possessing high catalytic activity towards iodide/tri-iodide redox shuttles.
Sci Rep
PUBLISHED: 01-24-2014
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Due to the two-dimensional confinement of electrons, single- and few-layer MoSe? nanostructures exhibit unusual optical and electrical properties and have found wide applications in catalytic hydrogen evolution reaction, field effect transistor, electrochemical intercalation, and so on. Here we present a new application in dye-sensitized solar cell as catalyst for the reduction of I?(-) to I(-) at the counter electrode. The few-layer MoSe? is fabricated by surface selenization of Mo-coated soda-lime glass. Our results show that the few-layer MoSe? displays high catalytic efficiency for the regeneration of I(-) species, which in turn yields a photovoltaic energy conversion efficiency of 9.00%, while the identical photoanode coupling with "champion" electrode based on Pt nanoparticles on FTO glass generates efficiency only 8.68%. Thus, a Pt- and FTO-free counter electrode outperforming the best conventional combination is obtained. In this electrode, Mo film is found to significantly decrease the sheet resistance of the counter electrode, contributing to the excellent device performance. Since all of the elements in the electrode are of high abundance ratios, this type of electrode is promising for the fabrication of large area devices at low materials cost.
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A hierarchical model for assembly of eukaryotic 60S ribosomal subunit domains.
Genes Dev.
PUBLISHED: 01-23-2014
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Despite having high-resolution structures for eukaryotic large ribosomal subunits, it remained unclear how these ribonucleoprotein complexes are constructed in living cells. Nevertheless, knowing where ribosomal proteins interact with ribosomal RNA (rRNA) provides a strategic platform to investigate the connection between spatial and temporal aspects of 60S subunit biogenesis. We previously found that the function of individual yeast large subunit ribosomal proteins (RPLs) in precursor rRNA (pre-rRNA) processing correlates with their location in the structure of mature 60S subunits. This observation suggested that there is an order by which 60S subunits are formed. To test this model, we used proteomic approaches to assay changes in the levels of ribosomal proteins and assembly factors in preribosomes when RPLs functioning in early, middle, and late steps of pre-60S assembly are depleted. Our results demonstrate that structural domains of eukaryotic 60S ribosomal subunits are formed in a hierarchical fashion. Assembly begins at the convex solvent side, followed by the polypeptide exit tunnel, the intersubunit side, and finally the central protuberance. This model provides an initial paradigm for the sequential assembly of eukaryotic 60S subunits. Our results reveal striking differences and similarities between assembly of bacterial and eukaryotic large ribosomal subunits, providing insights into how these RNA-protein particles evolved.
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Improving pore filling of gel electrolyte and charge transport in photoanode for high-efficiency quasi-solid-state dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 08-29-2013
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We demonstrate the enhancement of pore-filling and wettability of gel electrolyte in quasi-solid-state dye-sensitized solar cells (DSSCs) by developing a kinetically driven electrolyte infiltration approach, in which the air purging provides the driving force. This method renders fast electrolyte diffusion throughout the three-dimensional TiO2 nanoparticle network, promising for large-area device fabrication. In addition, for the first time we incorporate multiwalled carbon nanotubes into the anode of quasi-solid-state DSSCs to improve the charge transfer efficiency and fill factor. These advancements finally generate an efficiency exceeding 7.0%, much higher than the device efficiency of 5.5% fabricated by the conventional method.
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Paclitaxel nanosuspensions for targeted chemotherapy - nanosuspension preparation, characterization, and use.
Pharm Dev Technol
PUBLISHED: 04-25-2013
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Abstract Objective: The purpose of this work was to prepare a stable paclitaxel nanosuspension and test it for potential use as a targeted chemotherapeutic. Different particle coatings were employed to assess their impact on cellular uptake in vitro. In vivo work was then performed to demonstrate efficacy in tumor-bearing mouse models. Materials and method: Paclitaxel nanosuspensions were prepared using a homogenization process and coated with excipients. Surface charge was measured by zeta potential, potency by high-performance liquid chromatography, and solubility using an in-line UV probe. Cellular uptake studies were performed via flow cytometry. In vivo experiments were performed to determine residence time, maximum tolerated dose, and the efficacy of paclitaxel nanosuspensions (Paclitaxel-NS). Results: A stable paclitaxel nanosuspension was prepared and coated with various excipients. Studies in mice showed that the nanosuspension was well-tolerated and at least as effective as the IV Taxol control in prolonging mouse survival in a head and neck cancer model as well as an ovarian cancer model with a lower overall drug dose than the traditional IV administration route. Conclusions: The paclitaxel nanosuspension is suitable for cellular uptake. The nanosuspension was effective in prolonging life in two separate xenograft orthotopic murine cancer models through two separate routes of administration.
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Comparison of two gelatin and thrombin combination hemostats in a porcine liver abrasion model.
J Invest Surg
PUBLISHED: 03-20-2013
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Surgical hemostasis is achieved using adjunctive hemostats when conventional methods fail.
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A comparison model for measuring individual agreement.
J Biopharm Stat
PUBLISHED: 02-27-2013
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This article proposes a general comparison model for assessing individual agreement of k  ?  2 raters evaluating n subjects with m  ?  2 replicated readings. Users can explore total-rater agreement relative to intrarater agreement where any subset of the k raters can be selected in the numerator and denominator. Users are also allowed to compare intrarater agreement among selected raters. Based on the ratio of mean squared deviations (MSDs), two comparative agreement indices, total-intra ratio (TIR) and intra-intra ratio (IIR), are proposed. The TIR is a noninferiority assessment such that the differences of individual readings from different raters cannot be inferior by a prespecified margin to the differences of the replicated readings within raters. TIR can be used whether a reference exists or not. The method used by the Food and Drug Administration (FDA) for evaluating individual bioequivalence under relative scale becomes the special case of our approach. The IIR is a classical assessment such that the precision of selected raters can be better than; equal to; or worse than that of other raters. The estimation and statistical inference of TIR and IIR are obtained through GEE methodology.
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A genome-wide association study of bronchodilator response in Latinos implicates rare variants.
J. Allergy Clin. Immunol.
PUBLISHED: 01-16-2013
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The primary rescue medication to treat acute asthma exacerbation is the short-acting ?2-adrenergic receptor agonist; however, there is variation in how well a patient responds to treatment. Although these differences might be due to environmental factors, there is mounting evidence for a genetic contribution to variability in bronchodilator response (BDR).
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Inflammatory mediators gene polymorphisms in preeclampsia.
Hypertens Pregnancy
PUBLISHED: 09-06-2010
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To assess a possible relation between proinflammatory mediators (IL-1R1, IL-12, IL-18, TLR-2, and TLR-4) gene polymorphisms and preeclampsia (PE).
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Proteome profiling of aging in mouse models: differential expression of proteins involved in metabolism, transport, and stress response in kidney.
Proteomics
PUBLISHED: 02-03-2009
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Aging is a time-dependent complex biological phenomenon observed in various organs and organelles of all living organisms. To understand the molecular mechanism of age-associated functional loss in aging kidneys, we have analyzed the expression of proteins in the kidneys of young (19-22 wk) and old (24 months) C57/BL6 male mice using 2-DE followed by LC-MS/MS. We found that expression levels of 49 proteins were upregulated (p < or = 0.05), while that of only ten proteins were downregulated (p < or = 0.05) due to aging. The proteins identified belong to three broad functional categories: (i) metabolism (e.g., aldehyde dehydrogenase family, ATP synthase beta-subunit, malate dehydrogenase, NADH dehydrogenase (ubiquinone), hydroxy acid oxidase 2), (ii) transport (e.g., transferrin), and (iii) chaperone/stress response (e.g., Ig-binding protein, low density lipoprotein receptor-related protein associated protein 1, selenium-binding proteins (SBPs)). Some proteins with unknown functions were also identified as being differentially expressed. ATP synthase beta subunit, transferrin, fumarate hydratase, SBPs, and albumin are present in multiple forms, possibly arising due to proteolysis or PTMs. The above functional categories suggest specific mechanisms and pathways for age-related kidney degeneration.
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Androgen receptor gene polymorphism and polycystic ovary syndrome.
Int J Gynaecol Obstet
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Polycystic ovary syndrome (PCOS) is characterized by ovulatory dysfunction and hyperandrogenism. Its etiopathology is not well understood but genetic factors seem to have a role. Polymorphism of the androgen receptor (AR) gene has been associated with different androgen pattern diseases.
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Unincorporated iron pool is linked to oxidative stress and iron levels in Caenorhabditis elegans.
Biometals
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Free radicals or reactive oxygen species (ROS) are relatively short-lived and are difficult to measure directly; so indirect methods have been explored for measuring these transient species. One technique that has been developed using Escherichia coli and Saccharomyces cerevisiae systems, relies on a connection between elevated superoxide levels and the build-up of a high-spin form of iron (Fe(III)) that is detectable by electron paramagnetic resonance (EPR) spectroscopy at g = 4.3. This form of iron is referred to as "free" iron. EPR signals at g = 4.3 are commonly encountered in biological samples owing to mononuclear high-spin (S = 5/2) Fe(III) ions in sites of low symmetry. Unincorporated iron in this study refers to this high-spin Fe(III) that is captured by desferrioxamine which is detected by EPR at g value of 4.3. Previously, we published an adaptation of Fe(III) EPR methodology that was developed for Caenorhabditis elegans, a multi-cellular organism. In the current study, we have systematically characterized various factors that modulate this unincorporated iron pool. Our results demonstrate that the unincorporated iron as monitored by Fe(III) EPR at g = 4.3 increased under conditions that were known to elevate steady-state ROS levels in vivo, including: paraquat treatment, hydrogen peroxide exposure, heat shock treatment, or exposure to higher growth temperature. Besides the exogenous inducers of oxidative stress, physiological aging, which is associated with elevated ROS and ROS-mediated macromolecular damage, also caused a build-up of this iron. In addition, increased iron availability increased the unincorporated iron pool as well as generalized oxidative stress. Overall, unincorporated iron increased under conditions of oxidative stress with no change in total iron levels. However, when total iron levels increased in vivo, an increase in both the pool of unincorporated iron and oxidative stress was observed suggesting that the status of the unincorporated iron pool is linked to oxidative stress and iron levels.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

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

Video X seems to be unrelated to Abstract Y...

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