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Find video protocols related to scientific articles indexed in Pubmed.
Natural Product Libraries: Assembly, Maintenance, and Screening.
Planta Med.
PUBLISHED: 12-05-2013
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This review discusses successful strategies and potential pitfalls to assembling a natural product-based library suitable for high-throughput screening. Specific extraction methods for plants, microorganisms, and marine invertebrates are detailed, along with methods for generating a fractionated sub-library. The best methods to store, maintain and prepare the library for screening are addressed, as well as recommendations on how to develop a robust high-throughput assay. Finally, the logistics of moving from an assay hit to pure bioactive compound are discussed.
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VEGFD regulates blood vascular development by modulating SOX18 activity.
Blood
PUBLISHED: 11-22-2013
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Vascular endothelial growth factor-D (VEGFD) is a potent pro-lymphangiogenic molecule of tumour growth and is considered a key therapeutic target to modulate metastasis. Despite roles in pathological neo-lymphangiogenesis, the characterisation of an endogenous role for VEGFD in vascular development has remained elusive. Here, we used zebrafish to assay for genetic interactions between the Vegf/Vegf-receptor pathway and SoxF transcription factors and identified a specific interaction between Vegfd and Sox18. Double knockdown zebrafish embryos for Sox18/Vegfd and Sox7/Vegfd exhibit defects in arteriovenous differentiation. Supporting this observation, we found that Sox18/Vegfd double but not single knockout mice displayed dramatic vascular development defects. We find that VEGFD-MEK-ERK signalling modulates SOX18-mediated transcription, functioning at least in part by enhancing nuclear concentration and transcriptional activity in vascular endothelial cells. This work suggests that VEGFD-mediated pathologies include or involve an underlying dysregulation of SOXF-mediated transcriptional networks.
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Sesterterpene glycinyl-lactams: a new class of glycine receptor modulator from Australian marine sponges of the genus Psammocinia.
Org. Biomol. Chem.
PUBLISHED: 06-11-2013
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Bioassay guided fractionation of three southern Australian marine sponges of the genus Psammocinia, selected for their ability to modulate glycine-gated chloride channel receptors (GlyRs), yielded the rare marine sesterterpenes (-)-ircinianin (1) and (-)-ircinianin sulfate (2), along with the new biosynthetically related metabolites (-)-ircinianin lactam A (3), (-)-ircinianin lactam A sulfate (4), (-)-oxoircinianin (5), (-)-oxoircinianin lactam A (6) and (-)-ircinianin lactone A (7). Acetylation of 1 returned (-)-ircinianin acetate (8). Whole cell patch-clamp electrophysiology on 1-8 established 3 as an exceptionally potent and selective ?3 GlyR potentiator, and 6 as a selective ?1 GlyR potentiator. The discovery and characterization of sesterterpenes 1-8, and in particular the glycinyl-lactams 3 and 6, provide valuable new insights into GlyR pharmacology. These insights have the potential to inform and inspire the development of new molecular tools to probe GlyR distribution and function, and therapeutics to treat a wide array of GlyR mediated diseases and disorders.
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Australian marine sponge alkaloids as a new class of glycine-gated chloride channel receptor modulator.
Bioorg. Med. Chem.
PUBLISHED: 02-25-2013
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Chemical analysis of a specimen of the sponge Ianthella cf. flabelliformis returned two new sesquiterpene glycinyl lactams, ianthellalactams A (1) and B (2), the known sponge sesquiterpene dictyodendrillin (3) and its ethanolysis artifact ethyl dictyodendrillin (4), and five known sponge indole alkaloids, aplysinopsin (5), 8E-3-deimino-3-oxoaplysinopsin (6), 8Z-3-deimino-3-oxoaplysinopsin (7), dihydroaplysinopsin (8) and tubastrindole B (9). The equilibrated mixture 6/7 exhibited glycine-gated chloride channel receptor (GlyR) antagonist activity with a bias towards ?3 over ?1 GlyR, while tubastrindole B (9) exhibited a bias towards ?1 over ?3 GlyR. At low- to sub-micromolar concentrations, 9 was also a selective potentiator of ?1 GlyR, with no effect on ?3 GlyR-a pharmacology that could prove useful in the treatment of movement disorders such as spasticity and hyperekplexia. Our investigations into the GlyR modulatory properties of 1-9 were further supported by the synthesis of a number of structurally related indole alkaloids.
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High-throughput screening of Australian marine organism extracts for bioactive molecules affecting the cellular storage of neutral lipids.
PLoS ONE
PUBLISHED: 07-08-2011
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Mammalian cells store excess fatty acids as neutral lipids in specialised organelles called lipid droplets (LDs). Using a simple cell-based assay and open-source software we established a high throughput screen for LD formation in A431 cells in order to identify small bioactive molecules affecting lipid storage. Screening an n-butanol extract library from Australian marine organisms we identified 114 extracts that produced either an increase or a decrease in LD formation in fatty acid-treated A431 cells with varying degrees of cytotoxicity. We selected for further analysis a non-cytotoxic extract derived from the genus Spongia (Heterofibria). Solvent partitioning, HPLC fractionation and spectroscopic analysis (NMR, MS) identified a family of related molecules within this extract with unique structural features, a subset of which reduced LD formation. We selected one of these molecules, heterofibrin A1, for more detailed cellular analysis. Inhibition of LD biogenesis by heterofibrin A1 was observed in both A431 cells and AML12 hepatocytes. The activity of heterofibrin A1 was dose dependent with 20 µM inhibiting LD formation and triglyceride accumulation by ?50% in the presence of 50 µM oleic acid. Using a fluorescent fatty acid analogue we found that heterofibrin A1 significantly reduces the intracellular accumulation of fatty acids and results in the formation of distinct fatty acid metabolites in both cultured cells and in embryos of the zebrafish Danio rerio. In summary we have shown using readily accessible software and a relatively simple assay system that we can identify and isolate bioactive molecules from marine extracts, which affect the formation of LDs and the metabolism of fatty acids both in vitro and in vivo.
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Heterofibrins: inhibitors of lipid droplet formation from a deep-water southern Australian marine sponge, Spongia (Heterofibria) sp.
Org. Biomol. Chem.
PUBLISHED: 07-14-2010
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A bioassay-guided search for inhibitors of lipid droplet formation in a deep-water southern Australian marine sponge, Spongia (Heterofibria) sp., yielded six new compounds, fatty acids heterofibrins A1 (1) and B1 (4), along with related monolactyl and dilactyl esters, heterofibrins A2 (2), B2 (5), A3 (3) and B3 (6). Heterofibrin structures were assigned on the basis of detailed spectroscopic analysis, with comparison to chiral synthetic model compounds. All heterofibrins possess a diyne-ene moiety, while the monolactyl and dilactyl moiety featured in selected heterofibrins is unprecedented in the natural products literature. SAR by co-metabolite studies on the heterofibrins confirmed them to be non-cytotoxic, with the carboxylic acids 1 and 4 inhibiting lipid droplet formation in A431 fibroblast cell lines. Such inhibitors have potential application in the management of obesity, diabetes and atherosclerosis
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Ircinialactams: subunit-selective glycine receptor modulators from Australian sponges of the family Irciniidae.
Bioorg. Med. Chem.
PUBLISHED: 02-08-2010
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Screening an extract library of >2500 southern Australian and Antarctic marine invertebrates and algae for modulators of glycine receptor (GlyR) chloride channels identified three Irciniidae sponges that yielded new examples of a rare class of glycinyl lactam sesterterpene, ircinialactam A, 8-hydroxyircinialactam A, 8-hydroxyircinialactam B, ircinialactam C, ent-ircinialactam C and ircinialactam D. Structure-activity relationship (SAR) investigations revealed a new pharmacophore with potent and subunit selective modulatory properties against alpha1 and alpha3 GlyR isoforms. Such GlyR modulators have potential application as pharmacological tools, and as leads for the development of GlyR targeting therapeutics to treat chronic inflammatory pain, epilepsy, spasticity and hyperekplexia.
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Influence of perfusate composition on drug disposition in the in-situ perfused rat lung.
Int J Pharm
PUBLISHED: 05-12-2009
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This study compared the impact of two perfusates (A: 4.5% BSA-MOPS buffer and B: 4% dextran and 0.5% BSA-MOPS buffer) on the pharmacokinetics of the physiological markers [(3)H]-water, [(14)C]-sucrose, [(14)C]-antipyrine and Evans Blue-labelled albumin; and the drugs atenolol and propranolol using an in-situ single pass perfusion model in the rat lung. The multiple indicator dilution approach was used to define disposition. Similar perfusion pressures (17.6+/-6.71 vs 17.7+/-8.87 cm H(2)O), lung wet/dry ratio (6.14+/-1.16 vs 5.16+/-0.87), physiological spaces, and permeability-surface area products were found for the two perfusates. However, the recovery of propranolol using perfusate A (49.3+/-10.1%) was significantly higher than that using perfusate B (38.9+/-9.91%). This difference was consistent with changes in perfusate oncotic pressure associated with water and albumin distribution between the vascular, interstitial and cellular volumes of the lung.
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Toward a Virtual Lifetime Electronic Record: the Department of Veterans Affairs experience with the Nationwide Health Information Network.
AMIA Annu Symp Proc
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Health information exchange is expected of all electronic health records (EHRs) in order to ensure safe, quality care coordination. The U.S. Department of Veterans Affairs (VA) has a long history of information exchange across VA facilities and with the U.S. Department of Defense (DoD). However, since a majority of VA and DoD patients receive a portion of their health care from the private sector, it is essential that both agencies enable health information exchange with private sector providers. This has been made possible by the use of the specifications and trust agreement developed by the Nationwide Health Information Network (NwHIN) initiative. Currently, VA has 12 medical centers exchanging information with the private sector and is evaluating the value of the exchange. The authors report on the success of these pilots as well as on the challenges, which include stricter technical specifications and a more efficient approach to patient identification (ID) matching and consent management.
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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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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.