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Find video protocols related to scientific articles indexed in Pubmed.
Surgical Treatment of Incidental Gallbladder Cancer Discovered During or Following Laparoscopic Cholecystectomy.
World J Surg
PUBLISHED: 11-19-2014
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The optimal surgical management of patients with incidental gallbladder cancer (IGBC) and their long-term survival remains unclear.
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Identification of a selective G-quadruplex DNA binder using a multistep virtual screening approach.
Chem. Commun. (Camb.)
PUBLISHED: 11-13-2014
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To efficiently identify small molecules binding to a G-quadruplex structure while avoiding binding to duplex DNA, we performed a multistep structure-based virtual screening by simultaneously taking into account G-quadruplex DNA and duplex DNA. Among the 13 compounds selected, one outstanding ligand shows significant selectivity for G-quadruplex binding as determined using SPR, FRET-based competition and luciferase activity assay.
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Rhodium(iii)-catalyzed C-H/C-C activation sequence: vinylcyclopropanes as versatile synthons in direct C-H allylation reactions.
Chem. Commun. (Camb.)
PUBLISHED: 11-11-2014
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Succession of C-H activation and C-C activation was achieved by using a single rhodium(iii) catalyst. Vinylcyclopropanes were used as versatile coupling partners. Mechanistic studies suggest that the olefin insertion step is rate-determining and a facile ?-carbon elimination is involved, which represents a novel ring opening mode of vinylcyclopropanes.
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Rhizobium yantingense sp. nov., a mineral-weathering bacterium.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 11-08-2014
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A Gram negative, rod-shaped bacterial strain, H66T, was isolated from the surfaces of weathered rock (purple siltstone) which was found in Yanting, Sichuan Province of China. Cells of strain H66T were motile with peritrichous flagella. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain H66T belongs to the genus Rhizobium. It closely relates to Rhizobium huautlense SO2T (98.1 %), Rhizobium alkalisoli CCBAU 01393T (98.0 %), and Rhizobium cellulosilyticum ALA10B2T (98.0 %). Analysis of housekeeping genes recA, glnII and atpD showed low levels of sequence similarity (<92.0 %) between strain H66T and other recognized Rhizobium species. The predominant components of cellular fatty acids were summed feature 8 (C18:1 ?7c and/or C18:1 ?6c) and C16:0. The G + C content of strain H66T was 60.3 mol%. Strain H66T is described as a novel species of the genus Rhizobium based on the low level of DNA-DNA relatedness (ranging from 14.3 % to 40.0 %) to these type strains of species of the genus Rhizobium and unique phenotypic characteristics. The name Rhizobium yantingense sp. nov. is proposed for this novel species. The type strain is H66T (=CCTCCAB 2014007T= LMG 28229T).
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Chitinophaga longshanensis sp. nov., a mineral-weathering bacterium isolated from weathered rock.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 11-08-2014
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A Gram-stain-negative, aerobic, yellow-pigmented, non-motile, non-spore-forming, rod-shaped bacterial strain, Z29T, was isolated from the surface of weathered rock (potassic trachyte) from Nanjing, Jiangsu Province, PR China. Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain Z29T belongs to the genus Chitinophaga in the family Chitinophagaceae. The similarities of the 16S rRNA gene sequence between strain Z29T and other type strains of established species in the genus Chitinophaga ranged from 92.7 to 98.2%. The main fatty acids of strain Z29T were iso-C15:0, C16:0, iso-C13:0 and iso-C17:0. It also contained menaquinone 7 (MK-7) as the major respiratory quinone and homospermidine as the main polyamine. The polar lipid profile contained phosphatidylethanolamine, unknown aminolipids, unknown phospholipids, and unknown glycolipids. The total DNA G+C content of strain Z29T was 51.3 mol%. Phenotypic properties and chemotaxonomic data supported the affiliation of strain Z29T with the genus Chitinophaga. The low level of DNA-DNA relatedness (ranging from 14.6% to 29.8%) to other species of the genus Chitinophaga and the many phenotypic properties demonstrated that strain Z29T should represent a novel species of the genus Chitinophaga, for which the name Chitinophaga longshanensis sp. nov. is proposed. The type strain is Z29T (= CCTCC AB 2014066 T= LMG 28237 T).
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Downregulated expression of PTK6 is correlated with poor survival in esophageal squamous cell carcinoma.
Med. Oncol.
PUBLISHED: 11-07-2014
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To investigate the clinical prognostic value of protein tyrosine kinase 6 (PTK6) in patients with esophageal squamous cell carcinoma (ESCC), quantitative RT-PCR and Western blotting were utilized to measure the mRNA and protein expression levels of PTK6 in 29 and eight pairs of ESCC and peritumoral normal esophageal tissues, respectively. Furthermore, the expression of PTK6 protein in 210 ESCCs was examined with immunohistochemistry (IHC), and its clinical value was analyzed using Kaplan-Meier plots and the Cox proportional hazards regression model. The results found that the expression levels of both PTK6 mRNA and protein in ESCC tissues were significantly lower than those in peritumoral normal esophageal tissues. Regarding the IHC analysis of ESCC, the cytoplasmic expression of PTK6 was significantly correlated with tumor grade (P < 0.001). Compared with patients with low PTK6 expression, ESCC patients with overexpression of PTK6 displayed preferable disease-free survival (DFS) and overall survival (OS) (P < 0.001 and P = 0.001, respectively), especially in stage II disease (P = 0.002 and P = 0.021, respectively). PTK6 was evaluated as an independent prognostic factor for ESCC using multivariate Cox regression analysis. All data demonstrated that the expression level of PTK6 is an independent prognostic factor in ESCCs. Low expression of PTK6 is correlated with poor DFS and OS in ESCCs.
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Graphene oxide amplified fluorescence anisotropy for label-free detection of potassium ion.
Analyst
PUBLISHED: 11-07-2014
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Fluorescence anisotropy (FA) has attracted considerable attention, but it has been rarely applied for the detection of small molecules and metal ions because they are too small to induce evident FA changes. Although some mass amplifying strategies have been developed, the recognition probes need to be covalently modified with the fluorescent dyes, which is complex and expensive. To overcome this limitation, a new simple, label-free and cost-effective method for the sensitive detection of potassium ion (K(+)), by using graphene oxide (GO) as FA enhancer, a G-rich single stranded DNA (ssDNA) as recognition probe and acridine orange (AO) as FA reporting fluorophore, was established in this paper. In the absence of K(+), both ssDNA and AO are adsorbed on the surface of GO, and the FA of AO is enhanced greatly because the rotation of AO is coupled with the entire formation. After the addition of K(+), the ssDNA self-associates into the G-quadruplex structure. Then, AO can bind with the formed G-quadruplex strongly, keeping away from the surface of GO, and the FA of AO decreases significantly because of the relatively small size of the complex of AO and G-quadruplex. Thus K(+) can be detected sensitively in the range of 10 ?M-2 mM based on the evidently decreased FA. This method is a further improvement of the previous reported mass amplifying strategies because it does not require any covalent labelling of the recognition probe, and it can be potentially applied for detection of a variety of other targets.
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In situ labelling chemistry of respiratory syncytial viruses by employing the biotinylated host-cell membrane protein for tracking the early stage of virus entry.
Chem. Commun. (Camb.)
PUBLISHED: 11-06-2014
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An in situ labelling strategy was proposed to produce quantum dot-labelled respiratory syncytial viruses (RSVs) by incorporating the biotinylated membrane protein of the host cells into mature virions, followed by conjugation with streptavidin modified quantum dots (SA-QDs), which has the advantages such as convenience, efficiency and minor influence on viral infectivity and thus could be successfully applied to track the early stage of virus entry.
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Arthrobacter nanjingensis sp. nov., a mineral weathering bacterium isolated from forest soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 11-01-2014
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A Gram-positive-staining, non-motile, rod- or coccoid-shaped actinobacterium, designated strain A33(T), was isolated from a forest soil sample from Nanjing, Jiangsu Province, China. The strain grew optimally at 30 ºC, pH 7.0 and with 3% NaCl (w/v). Phylogenetic analysis of the strain based on 16S rRNA gene sequences showed it was most closely related to Arthrobacter woluwensis (98.4%), Arthrobacter humicola (97.5%), Arthrobacter globiformis (97.4%), Athrobacter oryzae (97.3%) and Arthrobacter cupressi (97.0%). The major cellular fatty acids were anteiso-C15:0, anteiso-C17:0 and iso-C15:0 and MK-9(H2) was the predominant respiratory quinone. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and three glycolipids. Cell-wall analysis revealed peptidoglycan type A3?, based on L-Lys-L-Ala, and cell-wall sugars were galactose and mannose. The genomic G+C content of strain A33(T) was 66.8 mol%. The low DNA-DNA relatedness values between strain A33(T) and recognized species of the genus Arthrobacter and many phenotypic properties supported the classification of strain A33(T) as a representative of a novel species of the genus Arthrobacter, for which the name Arthrobacter nanjingensis sp. nov. is proposed. The type strain is A33(T) (=CCTCC AB 2014069(T) =DSM 28237(T)).
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Chitinophaga qingshengii sp. nov., isolated from weathered rock surface.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 10-25-2014
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A novel type of mineral-weathering bacterium was isolated from weathered rock (potassic trachyte) surfaces collected from Nanjing (Jiangsu, China). Cells of strain JN246T were Gram-stain-negative, rod-shaped, and non-motile. Strain JN246T was aerobic, catalase- and oxidase-positive, and grew optimally at 28 °C and pH 7.0. On the basis of 16S rRNA gene sequence analysis, strain JN246T belonged to the genus Chitinophaga and the closest phylogenetic relatives were Chitinophaga eiseniae YC6729T (98.5 %), Chitinophaga terrae KP01T (96.8 %), and Chitinophaga jiangningensis JN53T (96.3 %). The major respiratory quinine was MK-7 and the major polyamine was homospermidine. The major fatty acids were iso-C15:0, C16:1?5c, C16:0, iso-C17:0 3-OH, iso-C15:0 3-OH, C14:O, C16:0 3-OH, C16:1?7c and/or C16:1?6c (summed feature 3), and C13:1. The polar lipid profile of strain JN246T consisted of phosphatidylethanolamine, unknown aminolipids and unknown lipids. The genomic DNA G + C content of strain JN246T was 48.8 mol%. Based on the low level of DNA-DNA relatedness (ranging from 22.6 % to 42.4 %) to these type strains of species of the genus Chitinophaga and unique phenotypic characteristics, strain JN246T represents a novel species of the genus Chitinophaga, for which the name Chitinophaga qingshengii sp. nov. is proposed. The type strain is JN246T (= CCTCC AB 2014201 T= JCM 30026 T).
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Selective and sensitive colorimetric detection of stringent alarmone ppGpp with Fenton-like reagent.
Analyst
PUBLISHED: 10-16-2014
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Stringent alarmone, namely, guanosine 3'-diphosphate-5'-diphosphate (ppGpp), is a global regulator that plays a critical role in the survival, growth, metabolism, and many other vital processes of microorganisms. Because of its structural similarity to normal nucleotides, it is also a challenge for the selective and sensitive detection of ppGpp nowadays. Herein, we developed a colorimetric method for the selective detection of ppGpp by inhibiting the redox reaction between Fenton-like reagent (composed of Fe(3+) and H2O2) with 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS). Owing to the strong coordination affinity between ppGpp and Fe(3+), the chromogenic reaction between ABTS and Fenton-like reagent, occurred in aqueous medium at 37 °C and resulted in a bluish-green solution, which was inhibited with the addition of ppGpp. This phenomenon forms the basis for the colorimetric detection of ppGpp, with a detection limit of 0.19 ?M and good selectivity for ppGpp over other nucleotides and anions. Furthermore, the results could be visualized by the naked eye, and the sensitivity of the naked-eye observation could even be further improved with the aid of the introduction of a background color.
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Post-pancreaticoduodenectomy hemorrhage: risk factors, managements and outcomes.
HBPD INT
PUBLISHED: 10-14-2014
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Post-pancreaticoduodenectomy (PD) hemorrhage (PPH) is an uncommon but serious complication. This retrospective study analyzed the risk factors, managements and outcomes of the patients with PPH.
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Discovery of a new fluorescent light-up probe specific to parallel G-quadruplexes.
Chem. Commun. (Camb.)
PUBLISHED: 09-02-2014
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A novel 2,4,5-triaryl-substituted imidazole (IZCM-1) has been found to display distinct and specific fluorescence enhancement upon binding to parallel G-quadruplexes. Such a sensitive and topology-specific probe is able to light up without affecting the topology or thermal stability of the G-quadruplex sample. Thus, these advantages distinguish IZCM-1 from other G-quadruplex probes.
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A colorimetric immunoassay for respiratory syncytial virus detection based on gold nanoparticles-graphene oxide hybrids with mercury-enhanced peroxidase-like activity.
Chem. Commun. (Camb.)
PUBLISHED: 08-19-2014
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A novel colorimetric immunoassay for highly sensitive detection of respiratory syncytial virus (RSV), one of the leading causes of severe lower respiratory tract infections in all age groups, has been proposed based on Hg(2+)-stimulated peroxidase-like activity of gold nanoparticles-graphene oxide (AuNPs-GO) hybrids. This metal ion-enhanced immunoassay shows high promise in the field of biomedical sciences.
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Mapping the zoonotic niche of Ebola virus disease in Africa.
Elife
PUBLISHED: 08-18-2014
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Ebola virus disease (EVD) is a complex zoonosis that is highly virulent in humans. The largest recorded outbreak of EVD is ongoing in West Africa, outside of its previously reported and predicted niche. We assembled location data on all recorded zoonotic transmission to humans and Ebola virus infection in bats and primates (1976-2014). Using species distribution models, these occurrence data were paired with environmental covariates to predict a zoonotic transmission niche covering 22 countries across Central and West Africa. Vegetation, elevation, temperature, evapotranspiration, and suspected reservoir bat distributions define this relationship. At-risk areas are inhabited by 22 million people; however, the rarity of human outbreaks emphasises the very low probability of transmission to humans. Increasing population sizes and international connectivity by air since the first detection of EVD in 1976 suggest that the dynamics of human-to-human secondary transmission in contemporary outbreaks will be very different to those of the past.
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[Development of online conventional array-based two-dimensional liquid chromatographic system for proteins separation in human plasma].
Se Pu
PUBLISHED: 07-30-2014
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Human plasma is one of the proteins-containing samples most difficult to characterize on account of the wide dynamic concentration range of its intact proteins. Herein, we developed a high-throughput conventional array-based two-dimensional liquid chromatographic system for proteins separation in human plasma in online mode. In the system, a conventional strong-anion exchange chromatographic column was used as the first separation dimension and eight parallel conventional reversed-phase liquid chromatographic columns were integrated as the second separation dimension. The fractions from the first dimension were sequentially transferred into the corresponding reversed-phase liquid chromatographic precolumns for retention and enrichment using a 10-port electrically actuated multi-position valve. The second dimensional solvent flow was directly and identically split into 8 channels. The fractions were concurrently back-flushed from the precolumns into the 8 conventional RP columns and were separated simultaneously. An 8-channel fraction collector was refitted to collect the reversed-phase liquid chromatographic fractions for further investigation. Bicinchoninic acid (BCA) dyein solution was conveniently used for high-abundance protein location. Two separation dimensions were relatively independent parts, as well as each channel of the second dimensional array separation. Therefore, the new system could improve the separation throughput and total peak capacity. The system was successfully applied for the separation of human plasma intact proteins. The results indicated the established system is an effective method for removing high abundance proteins in plasma and in-depth research in plasma proteomics.
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Controllable copper deficiency in Cu2-xSe nanocrystals with tunable localized surface plasmon resonance and enhanced chemiluminescence.
Nanoscale
PUBLISHED: 07-28-2014
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Copper chalcogenide nanocrystals (CuCNCs) as a type of semiconductor that can also act as efficient catalysts are rarely reported. Herein, we study water-soluble size-controlled Cu(2-x)Se nanocrystals (NCs), which are copper deficient and could be prepared by a redox reaction with the assistance of surfactants. We found them to have strong near-infrared localized surface plasmon resonance (LSPR) properties originating from the holes in the valence band, and also catalytic activity of more than a 500-fold enhancement of chemiluminescence (CL) in a luminol-H2O2 system. Investigations into the mechanisms behind these results showed that the high concentration of free carriers in Cu(2-x)Se NCs, which are derived from their high copper deficiencies that make Cu(2-x)Se NCs both good electron donors and acceptors with high ionic mobility, could greatly enhance the catalytic ability of Cu(2-x)Se NCs to facilitate electron-transfer processes and the decomposition of H2O2 into OH? and O2(?-), which are the commonly accepted key intermediates in luminol CL enhancement. Thus, it can be concluded that controllable copper deficiencies that are correlated with their near-infrared LSPR are critically responsible for the effective catalysis of Cu(2-x)Se NCs in the enhanced CL.
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Cellular signaling and production of galactose-deficient IgA1 in IgA nephropathy, an autoimmune disease.
J Immunol Res
PUBLISHED: 07-23-2014
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Immunoglobulin A (IgA) nephropathy (IgAN), the leading cause of primary glomerulonephritis, is characterized by IgA1-containing immunodeposits in the glomeruli. IgAN is a chronic disease, with up to 40% of patients progressing to end-stage renal disease, with no disease-specific treatment. Multiple studies of the origin of the glomerular immunodeposits have linked elevated circulating levels of aberrantly glycosylated IgA1 (galactose-deficient in some O-glycans; Gd-IgA1) with formation of nephritogenic Gd-IgA1-containing immune complexes. Gd-IgA1 is recognized as an autoantigen in susceptible individuals by anti-glycan autoantibodies, resulting in immune complexes that may ultimately deposit in the kidney and induce glomerular injury. Genetic studies have revealed that an elevated level of Gd-IgA1 in the circulation of IgAN patients is a hereditable trait. Moreover, recent genome-wide association studies have identified several immunity-related loci that associated with IgAN. Production of Gd-IgA1 by IgA1-secreting cells of IgAN patients has been attributed to abnormal expression and activity of several key glycosyltransferases. Substantial evidence is emerging that abnormal signaling in IgA1-producing cells is related to the production of Gd-IgA1. As Gd-IgA1 is the key autoantigen in IgAN, understanding the genetic, biochemical, and environmental aspects of the abnormal signaling in IgA1-producing cells will provide insight into possible targets for future disease-specific therapy.
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Cohnella nanjingensis sp. nov., an extracellular polysaccharide-producing bacterium isolated from soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 07-03-2014
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A Gram-stain-positive, rod-shaped, endospore-forming bacterium, strain D45(T), was isolated from soil in Nanjing, China. The organism grew optimally at 30 °C, pH 7.0 and with 0?% NaCl (w/v). The 16S rRNA gene sequence of the isolate showed similarities lower than 97?% with respect to species of the genus Cohnella. The predominant respiratory quinone was MK-7, with MK-6 present as a minor component; anteiso-C15?:?0 and iso-C16?:?0 were the major fatty acids. The polar lipids of strain D45(T) were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two aminophospholipids, four phospholipids, two glycolipids, one aminolipid and two lipids. The DNA G+C content was 59.5 mol%. DNA-DNA hybridization of the isolate with two reference strains showed relatedness values of 33.4?% with Cohnella ginsengisoli DSM 18997(T) and 25.8?% with Cohnella thermotolerans DSM 17683(T). The phylogenetic, chemotaxonomic and phenotypic data supported the classification of strain D45(T) as a representative of a novel species of the genus Cohnella, for which the name Cohnella nanjingensis sp. nov. is proposed. The type strain is D45(T) (?=?CCTCC AB 2014067(T)?=?DSM 28246(T)).
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Multiresidue analysis of 59 nonallowed substances and other contaminants in cosmetics.
J Sep Sci
PUBLISHED: 06-29-2014
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A method was developed for the determination of 59 glucocorticoids, sex hormones, nonsteroidal anti-inflammatory drugs, antibiotics, and other contaminants in cosmetics simultaneously by ultra high performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Acetonitrile was used to extract the sample, and the mixed sorbents were dispersed for purification. With the optimal conditions, the optimized pretreatment processes led to no significant interference on analysis from an extremely complicated sample matrix, and the linear ranges of 59 analytes were 0-480.0 ?g/kg with the correlation coefficients above 0.99 and the limits of quantification (S/N?10) were 5-40 ?g/kg. Statistical evaluation revealed that the average recoveries were in the range of 61.2-131.2%, and relative standard deviations were in the range of 2.0-22.8%, meanwhile the interday precision ranged from 3.8 to 21.8%. This method is simple, fast, and credible, and it can be applied to simultaneous screening and determination of various classes of substances under investigations illegally presented in cosmetic products, covering a wide diversity of polarities, and pKa values.
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Luminescent golden silk and fabric through in situ chemically coating pristine-silk with gold nanoclusters.
Biomaterials
PUBLISHED: 06-20-2014
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Silk is an excellent natural material and has been used for a variety of applications. Modification of the pristine silk is usually needed depending on the intended purpose. The technical treatments involved in the modification not only should be easy, rapid, environmentally friendly, and cheap but should also retain the features of the pristine silk. Herein, we demonstrate that luminescent silk and fabric can be produced through nanotechnology. The surface of the natural silk fiber is chemically coated with luminescent gold nanoclusters (AuNCs) composed of tens to hundreds of Au atoms through a redox reaction between the protein-based silk and an Au salt precursor. The luminescent silk coated with AuNCs (called golden silk) possesses good optical properties, including a relatively long wavelength emission, high quantum yields, a long fluorescent lifetime, and photostability. Moreover, golden silk prepared this way has better mechanical properties than pristine silk, is better able to inhibit UV, and has lower toxicity in vitro. This work not only provides an effective strategy for in situ preparation of luminescent metal nanoclusters on a solid substrate but also paves the way for large-scale and industrialized production of novel silk-based materials or fabrics through nanotechnology.
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Development of a new colorimetric and red-emitting fluorescent dual probe for G-quadruplex nucleic acids.
Chem. Commun. (Camb.)
PUBLISHED: 05-21-2014
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A tailor-made colorimetric and red-emitting fluorescent dual probe for G-quadruplex nucleic acids was developed by incorporating a coumarin-hemicyanine fluorophore into an isaindigotone framework. The significant and distinct changes in both the color and fluorescence of this probe enable the label-free and visual detection of G-quadruplex structures.
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Airflow-directed in situ electrospinning of a medical glue of cyanoacrylate for rapid hemostasis in liver resection.
Nanoscale
PUBLISHED: 05-20-2014
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Rapid hemostasis of solitary organs is still a big challenge in surgical procedures or after major trauma in both civilians and on the battlefield. Here, we report the first use of an airflow-directed in situ electrospinning method to precisely and homogeneously deposit a medical glue of n-octyl-2-cyanoacrylate (OCA) ultrathin fibers onto a wound surface to realize rapid hemostasis in dozens of seconds. In vivo and in vitro experiments on pig liver resection demonstrate that the self-assembled electrospun OCA membrane with high strength, good flexibility and integrity is very compact and no fluid seeping is observed even under a pressure of 147 mm Hg. A similar effect has been achieved in an in vivo experiment on pig lung resection. The results provide a very promising alternative for rapid hemostasis of solitary organs as well as other traumas, providing evidence that the postoperative drainage tube may not be always necessary for surgery in the near future.
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Complete Genome Sequence of Dyella jiangningensis Strain SBZ3-12, Isolated from the Surfaces of Weathered Rock.
Genome Announc
PUBLISHED: 05-17-2014
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Dyella jiangningensis strain SBZ3-12 can weather biotite and release Al and Fe from biotite under nutrient-poor conditions. Here, we report the first complete genome sequence of D. jiangningensis strain SBZ3-12, which may facilitate a better understanding of the molecular mechanism behind mineral weathering.
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Bacillus qingshengii sp. nov., a rock-weathering bacterium isolated from weathered rock surface.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 05-06-2014
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A novel type of rock-weathering bacterium was isolated from weathered rock (tuff) surface collected from Dongxiang (Jiangxi, eastern China). Cells of strain G19(T) were Gram-reaction-positive, rod-shaped, endospore-forming and non-motile. The strain was aerobic, catalase- and oxidase-positive, and grew optimally at 30 °C and pH 7.0. On the basis of 16S rRNA gene sequence analysis, strain G19(T) was shown to belong to the genus Bacillus and the closest phylogenetic relatives were Bacillus aryabhattai B8W22(T) (97.4%) and Bacillus megaterium IAM 13418(T) (97.1%). The DNA G+C content was 36.7 mol% and the predominant respiratory quinone was MK-7. The major fatty acids were iso-C14 : 0, iso-C15 : 0 and anteiso-C15 : 0. The polar lipid profile of strain G19(T) contained phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol and an unidentified lipid. Based on the low level of DNA-DNA relatedness (ranging from 49.4% to 55.0%) to these type strains of species of the genus Bacillus and unique phenotypic characteristics, strain G19(T) represents a novel species of the genus Bacillus, for which the name Bacillus qingshengii sp. nov. is proposed. The type strain is G19(T) (?= CCTCC AB 2013273(T)?= JCM 19454(T)).
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Mechanistic studies on the anticancer activity of 2,4-disubstituted quinazoline derivative.
Biochim. Biophys. Acta
PUBLISHED: 04-16-2014
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Accelerated proliferation of solid tumor and hematologic cancer cells is related to accelerated transcription of ribosomal DNA by the RNA polymerase I to produce elevated level of ribosomal RNA. Therefore, down-regulation of RNA polymerase I transcription in cancer cells is an important anticancer therapeutic strategy.
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Syntheses of tanshinone anhydrides and their suppression on oxidized LDL uptake in macrophages and foam cell formation.
Pharmazie
PUBLISHED: 04-11-2014
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We synthesized eight tanshinone anhydrides and the alcoholytic derivatives through a mild oxygen-insertion under Pd/C catalytic hydrogenation conditions. The suppressive effects of the anhydrides on the oxidized low-density lipoprotein (oxLDL) uptake and the oxLDL-induced macrophage-derived foam cell formation were studied. Our results revealed that both anhydrides 1a and 2a could significantly suppress the oxLDL uptake in macrophages and the foam cell formation at micromolar level, which might be partially attributed to their inhibition of oxLDL-induced LOX-1 expression in macrophages.
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Effect on push-out bond strength of glass-fiber posts functionalized with polydopamine using different adhesives.
J Adhes Dent
PUBLISHED: 04-01-2014
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To evaluate the push-out bond strengths of prefabricated glass-fiber posts (Beijing Oya Biomaterials) with polydopamine functionalized to root dentin using two different resin cements (Paracore and RelyX Unicem) in different root regions (cervical, middle, and apical).
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Predicting the risk of avian influenza A H7N9 infection in live-poultry markets across Asia.
Nat Commun
PUBLISHED: 03-19-2014
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Two epidemic waves of an avian influenza A (H7N9) virus have so far affected China. Most human cases have been attributable to poultry exposure at live-poultry markets, where most positive isolates were sampled. The potential geographic extent of potential re-emerging epidemics is unknown, as are the factors associated with it. Using newly assembled data sets of the locations of 8,943 live-poultry markets in China and maps of environmental correlates, we develop a statistical model that accurately predicts the risk of H7N9 market infection across Asia. Local density of live-poultry markets is the most important predictor of H7N9 infection risk in markets, underscoring their key role in the spatial epidemiology of H7N9, alongside other poultry, land cover and anthropogenic predictor variables. Identification of areas in Asia with high suitability for H7N9 infection enhances our capacity to target biosurveillance and control, helping to restrict the spread of this important disease.
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Effects of intensive insulin therapy combined with low molecular weight heparin anticoagulant therapy on severe pancreatitis.
Exp Ther Med
PUBLISHED: 03-11-2014
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The current study explored the effects of intensive insulin therapy (IIT) combined with low molecular weight heparin (LMWH) anticoagulant therapy on severe acute pancreatitis (SAP). A total of 134 patients with SAP that received treatment between June 2008 and June 2012 were divided randomly into groups A (control; n=33), B (IIT; n=33), C (LMWH; n=34) and D (IIT + LMWH; n=34). Group A were treated routinely. Group B received continuous pumped insulin, as well as the routine treatment, to maintain the blood sugar level between 4.4 and 6.1 mmol/l. Group C received a subcutaneous injection of LMWH every 12 h in addition to the routine treatment. Group D received IIT + LMWH and the routine treatment. The white blood cell count, hemodiastase, serum albumin, arterial partial pressure of oxygen and prothrombin time were recorded prior to treatment and 1, 3, 5, 7 and 14 days after the initiation of treatment. The intestinal function recovery time, incidence rate of multiple organ failure (MOF), length of hospitalization and fatality rates were observed. IIT + LMWH noticeably increased the white blood cell count, hemodiastase level, serum albumin level and the arterial partial pressure of oxygen in the patients with SAP (P<0.05). It markedly shortened the intestinal recovery time and the length of stay and reduced the incidence rate of MOF, the surgery rate and the fatality rate (P<0.05). It did not aggravate the hemorrhagic tendency of SAP (P>0.05). IIT + LMWH had a noticeably improved clinical curative effect on SAP compared with that of the other treatments.
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Synergistic induction of apoptosis by methylseleninic acid and cisplatin, the role of ROS-ERK/AKT-p53 pathway.
Mol. Pharm.
PUBLISHED: 03-03-2014
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Cisplatin-based therapy is one of the most important chemotherapy treatments for cancers. However, its efficacy is greatly limited by drug resistance and undesirable side effects. Therefore, it is of great importance to develop chemosensitizing agents to cisplatin. In the present study, we demonstrated the strategy to use methylseleninic acid (MeSe) as a synergistic agent of cisplatin and elucidated their action mechanisms. The combination of MeSe and cisplatin exhibited synergistic anticancer efficacy and achieved greater selectivity between cancer cell and normal cell. By inducing intracellular oxidative stress, MeSe potentiated cisplatin-induced DNA damage and led to enhanced p53 phosphorylation, followed by increased activation of both mitochondrial and death receptor pathway. Down-regulation of phosphorylated AKT and ERK also played important roles in the synergistic effects of MeSe and cisplatin. Our results suggested that the strategy to apply MeSe as a synergistic agent to cisplatin could be a highly efficient way to achieve anticancer synergism by targeting the intracellular redox system. MeSe might be a candidate for clinical application as a chemosensitizer to cisplatin-based therapy for cancer treatments, especially for hepatocellular carcinoma.
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Defining the geographical range of the Plasmodium knowlesi reservoir.
PLoS Negl Trop Dis
PUBLISHED: 03-01-2014
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The simian malaria parasite, Plasmodium knowlesi, can cause severe and fatal disease in humans yet it is rarely included in routine public health reporting systems for malaria and its geographical range is largely unknown. Because malaria caused by P. knowlesi is a truly neglected tropical disease, there are substantial obstacles to defining the geographical extent and risk of this disease. Information is required on the occurrence of human cases in different locations, on which non-human primates host this parasite and on which vectors are able to transmit it to humans. We undertook a systematic review and ranked the existing evidence, at a subnational spatial scale, to investigate the potential geographical range of the parasite reservoir capable of infecting humans.
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Synthesis and characterization of 1H-phenanthro[9,10-d]imidazole derivatives as multifunctional agents for treatment of Alzheimer's disease.
Biochim. Biophys. Acta
PUBLISHED: 02-27-2014
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Alzheimer's disease (AD) is a progressive neurodegenerative brain disorder that is characterized by dementia, cognitive impairment, and memory loss. Diverse factors are related to the development of AD, such as increased level of ?-amyloid (A?), acetylcholine, metal ion deregulation, hyperphosphorylated tau protein, and oxidative stress.
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Cellular nucleic acid binding protein suppresses tumor cell metastasis and induces tumor cell death by downregulating heterogeneous ribonucleoprotein K in fibrosarcoma cells.
Biochim. Biophys. Acta
PUBLISHED: 02-13-2014
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Cellular nucleic acid binding protein (CNBP) has been implicated in vertebrate craniofacial development and in myotonic dystrophy type 2 (DM2) and sporadic inclusion body myositis (sIBM) human diseases by controlling cell proliferation and survival to mediate neural crest expansion. CNBP has been found to bind single-stranded nucleic acid and promote rearrangements of nucleic acid secondary structure in an ATP-independent manner, acting as a nucleic acid chaperone.
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G-quadruplex-mediated regulation of telomere binding protein POT1 gene expression.
Biochim. Biophys. Acta
PUBLISHED: 02-10-2014
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Telomere is protected by its G-quadruplex, T-loop structure, telomerase, and binding protein complex. Protein POT1 (protection of telomeres 1) is one subunit of telomere binding protein complex Shelterin. POT1 acts as a regulator of telomerase-dependent telomere length, and it can help telomere to form D-loop structure to stabilize telomere. POT1 protects telomere ends from ATR-dependent DNA damage response as well.
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"One-off" complete radiofrequency ablation for hepatocellular carcinoma in a "high-risk location" adjacent to the major bile duct and hepatic blood vessel.
Cell Biochem. Biophys.
PUBLISHED: 02-06-2014
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Radiofrequency ablation (RFA) is an effective, minimally invasive treatment option for unresectable hepatocellular carcinomas (HCCs) located in high-risk areas or for patients with poor hepatic functional reserve. However, for tumors adjacent to major bile ducts and hepatic blood vessels, complete ablation is difficult to achieve for fear of causing a postoperative bile leak, bilioma or bile duct stenosis. Therefore, RFA is often combined with multiple alcohol injections to eliminate residual tumor tissues in adjacent bile duct or blood vessels; however, the injections directly affect the efficacy and prognosis of RFA. This study reports three successful "one-off" cases of complete ablation of HCCs adjacent to major bile ducts and blood vessels in neighboring hepatic segments or hepatic lobes, highlighting both the efficacy and safety of RFA for HCC tumors in these high-risk locations.
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The zinc finger transcription factor ZFX is required for maintaining the tumorigenic potential of glioblastoma stem cells.
Stem Cells
PUBLISHED: 01-30-2014
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Glioblastomas are highly lethal brain tumors containing tumor-propagating glioma stem cells (GSCs). The molecular mechanisms underlying the maintenance of the GSC phenotype are not fully defined. Here we demonstrate that the zinc finger and X-linked transcription factor (ZFX) maintains GSC self-renewal and tumorigenic potential by upregulating c-Myc expression. ZFX is differentially expressed in GSCs relative to non-stem glioma cells and neural progenitor cells. Disrupting ZFX by shRNA reduced c-Myc expression and potently inhibited GSC self-renewal and tumor growth. Ectopic expression of c-Myc to its endogenous level rescued the effects caused by ZFX disruption, supporting that ZFX controls GSC properties through c-Myc. Furthermore, ZFX binds to a specific sequence (GGGCCCCG) on the human c-Myc promoter to upregulate c-Myc expression. These data demonstrate that ZFX functions as a critical upstream regulator of c-Myc and plays essential roles in the maintenance of the GSC phenotype. This study also supports that c-Myc is a dominant driver linking self-renewal to malignancy.
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Stabilization of VEGF G-quadruplex and inhibition of angiogenesis by quindoline derivatives.
Biochim. Biophys. Acta
PUBLISHED: 01-28-2014
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Angiogenesis is thought to be important in tumorigenesis and tumor progress. Vascular endothelial growth factor (VEGF) is a pluripotent cytokine and angiogenic growth factor that plays crucial roles in embryonic development and tumor progression. In many types of cancer, VEGF is overexpressed and is generally associated with tumor progression and survival rate. The polypurine/polypyrimidine sequence located upstream of the promoter region in the human VEGF gene can form specific parallel G-quadruplex structures, raising the possibility for transcriptional control of VEGF through G-quadruplex ligands.
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Novel Method of Fabricating Individual Trays for Maxillectomy Patients by Computer-Aided Design and Rapid Prototyping.
J Prosthodont
PUBLISHED: 01-11-2014
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Making impressions for maxillectomy patients is an essential but difficult task. This study developed a novel method to fabricate individual trays by computer-aided design (CAD) and rapid prototyping (RP) to simplify the process and enhance patient safety.
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Selenium Accumulation in Unicellular Green Alga Chlorella vulgaris and Its Effects on Antioxidant Enzymes and Content of Photosynthetic Pigments.
PLoS ONE
PUBLISHED: 01-01-2014
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The aim of the present study was to investigate selenite effects in the unicellular green algae Chlorella vulgaris as a primary producer and the relationship with intracellular bioaccumulation. The effects of selenite were evaluated by measuring the effect of different selenite concentrations on algal growth during a 144 h exposure period. It was found that lower Se concentrations (?75 mg L-1) positively promoted C. vulgaris growth and acted as antioxidant by inhibiting lipid peroxidation (LPO) and intracellular reactive oxygen species (ROS). The antioxidative effect was associated with an increase in guaiacol peroxidase (GPX), catalase (CAT), superoxide dismutase (SOD) and photosynthetic pigments. Meanwhile, significant increase in the cell growth rate and organic Se content was also detected in the algae. In contrast, these changes were opposite in C. vulgaris exposed to Se higher than 100 mg L-1. The antioxidation and toxicity appeared to be correlated to Se bioaccumulation, which suggests the appropriate concentration of Se in the media accumulation of C. vulgaris should be 75 mg L-1. Taken together, C. vulgaris possesses tolerance to Se, and Se-Chlorella could be developed as antioxidative food for aquaculture and human health.
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Sphingomonas yantingensis sp. nov., a mineral-weathering bacterium isolated from purplish paddy soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 12-20-2013
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A novel type of mineral-weathering bacterium was isolated from purplish soils collected from Yanting (Sichuan, southwestern China). Cells of strain 1007T were Gram-negative and rod-shaped, motile and yellow-pigmented. The isolate was strictly aerobic, catalase- and oxidase-positive, and grew optimally at 30°C and pH 7.0. The genomic G+C content of strain 1007T was (67 ± 0.7) mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 1007T belonged to the genus Sphingomonas and was most closely related to Sphingomonas pruni IFO 15498T (97.3%), Sphingomonas mali IFO 15500T (97.2%), Sphingomonas japonica KC7T (97.2%) and Sphingomonas koreensis JSS-26T (97.0%). This affiliation of strain 1007T to the genus Sphingomonas was confirmed by the presence of Q-10 as the major ubiquinone, sphingoglycolipid, C14:0 2-OH and by the absence of 3-hydroxy fatty acids. The major polyamine was homospermidine. The main cellular fatty acids included summed feature 8 (comprising C18:1?7c or C18:1?6c) and C16:0. Based on the low level of DNA-DNA relatedness (ranging from 26.1% to 58.7%) to these type species of the genus Sphingomonas and unique phenotypic characteristics, strain 1007T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas yantingensis is proposed. The type strain is 1007T (=DSMZ 27244T=JCM 19201T=CCTCC AB 2013146T).
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Real-time dark-field scattering microscopic monitoring of the in situ growth of single ag@hg nanoalloys.
ACS Nano
PUBLISHED: 12-02-2013
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A comprehensive understanding of the growth mechanism of nanoalloys is beneficial in designing and synthesizing nanoalloys with precisely tailored properties to extend their applications. Herein, we present the investigation in this aspect by real-time monitoring of the in situ growth of single Ag@Hg nanoalloys, through direct amalgamation of Ag nanoparticles with elemental mercury, by dark-field scattering microscopy. Four typically shaped Ag nanoparticles, such as rods, triangular bipyramids, cubes, and spheres, were used as seeds for studying the growth of Ag@Hg nanoalloys. The scattered light of Ag nanoparticles of different shapes, on exposure to the growth solution, exhibited a noticeable blue-shift followed by a red-shift, suggesting the growth of Ag@Hg nanoalloys. The formation of Ag@Hg nanoalloys was confirmed by scanning electron microscopy, high-resolution transmit electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and elemental mapping and line scanning. Further analysis of the time-dependent spectral data and morphological change of single nanoparticles during the growth led to the visual identification of the growth mechanism of single Ag@Hg nanoalloys. Three important steps were involved: first, rapid adsorption of Hg atoms onto Ag nanoparticles; second, initial diffusion of Hg atoms into Ag nanoparticles, rounding or shortening the particles; third, further diffusion of Hg atoms leading to the formation of spherical Ag@Hg nanoalloys. On the basis of these results, Ag@Hg nanoalloys with given optical properties can be synthesized. Moreover, dark-field scattering microscopy is expected to be a powerful tool used for real-time monitoring of the in situ growth of other metal nanoparticles.
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Myroides xuanwuensis sp. nov., a mineral-weathering bacterium isolated from forest soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 10-24-2013
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A Gram-negative, aerobic, non-motile, yellow-pigmented, rod-shaped bacterium, designated strain TH-19T, was isolated from a forest soil sample in Jiangsu province, China. On the basis of 16S rRNA gene sequence similarity, strain TH-19T was shown to belong to the genus Myroides, a member of Bacteroidetes, and was related to Myroides odoratimimus LMG 4029T (98.7% similarity to the type strain), Myroides profundi D25T (98.2%), and Myroides marinus JS-08T (97.5%). Strain TH-19T contained menaquinone-6 (MK-6) as the predominant menaquinone, and the dominant fatty acids were iso-C15:0 and iso-C17:03-OH. The DNA G+C content of strain TH-19T was 37.2 mol%. The DNA-DNA relatedness values of strain TH-19T with Myroides odoratimimus JCM 7460T, Myroides profundi D25T and Myroides marinus JS-08T were below 70%. Based on phenotypic, genotypic and phylogenetic evidence, it is suggested that strain TH-19T represents a novel species of the genus Myroides, for which the name Myroides xuanwuensis sp. nov. is proposed. The type strain is TH-19T (=CCTCC AB 2013145T=JCM 19200T).
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Depth-Related Changes in Community Structure of Culturable Mineral Weathering Bacteria and in Weathering Patterns Caused by Them along Two Contrasting Soil Profiles.
Appl. Environ. Microbiol.
PUBLISHED: 09-27-2013
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Bacteria play important roles in mineral weathering and soil formation. However, few reports of mineral weathering bacteria inhabiting subsurfaces of soil profiles have been published, raising the question of whether the subsurface weathering bacteria are fundamentally distinct from those in surface communities. To address this question, we isolated and characterized mineral weathering bacteria from two contrasting soil profiles with respect to their role in the weathering pattern evolution, their place in the community structure, and their depth-related changes in these two soil profiles. The effectiveness and pattern of bacterial mineral weathering were different in the two profiles and among the horizons within the respective profiles. The abundance of highly effective mineral weathering bacteria in the Changshu profile was significantly greater in the deepest horizon than in the upper horizons, whereas in the Yanting profile it was significantly greater in the upper horizons than in the deeper horizons. Most of the mineral weathering bacteria from the upper horizons of the Changshu profile and from the deeper horizons of the Yanting profile significantly acidified the culture media in the mineral weathering process. The proportion of siderophore-producing bacteria in the Changshu profile was similar in all horizons except in the Bg2 horizon, whereas the proportion of siderophore-producing bacteria in the Yanting profile was higher in the upper horizons than in the deeper horizons. Both profiles existed in different highly depth-specific culturable mineral weathering community structures. The depth-related changes in culturable weathering communities were primarily attributable to minor bacterial groups rather than to a change in the major population structure.
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Comprehensive screening for multi-class veterinary drug residues and other contaminants in muscle using column-switching UPLC-MS/MS.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess
PUBLISHED: 09-26-2013
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A quantitative multi-class analytical method covering more than 226 veterinary drugs and other contaminants in muscle, belonging to different drug families, was developed. The method is based on liquid-liquid extraction, purification by low-temperature clean-up and dispersive solid-phase extraction (D-SPE), and analysis was conducted in two analytical runs by column-switching UPLC coupled with electrospray ionisation and tandem mass spectrometry (UPLC-ESI-MS/MS). For most of the target analytes, the optimised pre-treatment processes led to no significant interference from the sample matrix. The limit of quantification varied from 0.05 to 10 µg kg(-1). Statistical evaluation indicated that average recoveries spiked into pork were in the range from 62.4% to 138.8%, and the relative standard deviations were in the range from 2.8% to 26.6% (intra-day precision). The availability of this method will contribute to a better safety assurance of meat with a significant reduction of both effort and time.
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Chitinophaga jiangningensis sp. nov., a mineral-weathering bacterium.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 09-19-2013
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A Gram-negative, rod-shaped bacterial strain, JN53T, was isolated from the surfaces of weathered rock (potassic trachyte) from Nanjing, Jiangsu Province, PR China. Strain JN53T grew optimally at 30 °C, pH 7.0. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain JN53T belongs to the genus Chitinophaga in the family Chitinophagaceae. It was related most closely to Chitinophaga terrae KP01T (97.3% 16S r RNA gene sequence similarity), Chitinophaga eiseniae YC6729T (96.3%). Strain JN53T contained MK-7 as the major menaquinone and homospermidine as the major polymine. The main fatty acids of strain JN53T were iso-C15:0, C16:1?5c, C16:1?7c and/or C16:1?6c, iso-C17:0 3-OH, C16:0, iso-C15:0 3-OH, and C16:0 3-OH. The polar lipid profile contained phosphatidylethanolamine, unknown aminolipids and unknown lipids. The total DNA G + C content of strain JN53T was 49.7 mol%. The low level of DNA-DNA relatedness to other species of the genus Chitinophaga and the many phenotypic properties that distinguished strain JN53T from recognized species of this genus demonstrated that isolate JN53T should be classified as representing a novel species of the genus Chitinophaga. The name Chitinophaga jiangningensis sp. nov. is proposed for this novel species. The type strain is JN53T (=CCTCC AB 2013166 T = JCM 19354 T).
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Rutaecarpine analogues reduce lipid accumulation in adipocytes via inhibiting adipogenesis/lipogenesis with AMPK activation and UPR suppression.
ACS Chem. Biol.
PUBLISHED: 09-06-2013
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Obesity is characterized by expansion of adipose tissue, which results from an increase in adipocyte number (adipogenesis) and adipocyte size (lipogenesis). A reversal of these processes has been suggested to be a potential antiobetic therapy. Rutaecarpine (Rut) and its novel analogues (R17 and R18) were identified to exert potent effect in reducing lipid accumulation during adipocyte differentiation in 3T3-L1 adipocytes with little cytotoxicity. All three compounds reduced lipid accumulation in a dose-dependent manner, while R17 and R18 exhibited much more potent inhibitory effects compared to that of Rut. Further studies showed that R17 suppressed both adipogenesis and lipogenesis during all stages of adipocyte differentiation as indicated by the reduced protein and mRNA levels of key regulators of adipogenesis/lipogenesis, including PPAR?, C/EBP?, SREBP-1c, ACC, FAS, and SCD-1. We next examined the effect of R17 on the UPR pathway and the results showed that the UPR markers (PERK, eIF2?, IRE1?, and spliced XBP1 mRNA) were all significantly reduced by R17. Further studies revealed that R17 persistently activated AMPK during differentiation, suggesting that the AMPK may be an upstream mechanism for the effect of R17 on adipogenesis and lipogenesis via the adipogenic/lipogenic markers and the UPR pathway. Finally, studies in fast/refeeding mice demonstrated that R17 administration was able to reduce epididymal fat mass and the levels of plasma TG and FFA in vivo. Our results suggest that rutaecarpine analogues may have therapeutic potential for obesity and related metabolic disorders. The mechanism involves the suppression of adipogenic/lipogenic proteins and the suppression of the UPR pathway possibly via the AMPK.
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Calpastatin prevents NF-?B-mediated hyperactivation of macrophages and attenuates colitis.
J. Immunol.
PUBLISHED: 08-28-2013
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Calpain enzymes proteolytically modulate cellular function and have been implicated in inflammatory diseases. In this study, we found that calpain levels did not differ between intestinal tissues from inflammatory bowel disease (IBD) patients and healthy controls, but IBD tissues showed increased levels of the endogenous calpain inhibitor, calpastatin (CAST). To investigate the role of CAST in the immune system during IBD, mice were x-ray irradiated, reconstituted with either CAST-knockout (KO) or wild-type (WT) bone marrow, and subjected to dextran sulfate sodium-induced colitis. CAST-KO recipients with induced colitis exhibited more severe weight loss, bloody diarrhea, and anemia compared with WT controls. Histological evaluation of colons from KO recipients with colitis revealed increased inflammatory pathology. Macrophages purified from the colons of KO recipients had higher IL-6, TNF-?, and IFN-? mRNA levels compared with WT controls. Mechanistic investigations using small interfering RNA and KO bone marrow to generate CAST-deficient macrophages showed that CAST deficiency during activation with bacterial pathogen associated molecular patterns, including heat-killed Enterococcus faecalis or CpG DNA, led to increased I?B cleavage, NF-?B nuclear localization, and IL-6 and TNF-? secretion. Thus, CAST plays a central role in regulating macrophage activation and limiting pathology during inflammatory disorders like IBD.
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Syntheses of diacyltanshinol derivatives and their suppressive effects on macrophage foam cell formation by reducing oxidized LDL uptake.
Bioorg. Chem.
PUBLISHED: 08-18-2013
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A series of diacyltanshinol derivatives were synthesized by esterifying the corresponding o-hydroquinones of tanshinones. The suppressive effects of the synthesized compounds on oxidized low-density lipoprotein (oxLDL) uptake and oxLDL-induced macrophage-derived foam cell formation were evaluated. Our results indicated that the nicotinate derivatives 1a and 2a, modified from tanshinone IIA and cryptotanshinone, showed stronger suppressive activity on oxLDL uptake and the resultant foam cell formation relative to tanshinone IIA. Western Blot analysis indicated that derivatives 1a and 2a could dose-dependently inhibit the expression of oxLDL-induced LOX-1, implying that the suppressive effects of 1a and 2a on oxLDL uptake and foam cell formation could be at least partially attributed to the inhibition of LOX-1 expression in macrophages.
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Syntheses and characterization of non-bisphosphonate quinoline derivatives as new FPPS inhibitors.
Biochim. Biophys. Acta
PUBLISHED: 08-09-2013
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Farnesyl pyrophosphate synthase (FPPS) is a key regulatory enzyme in the biosynthesis of cholesterol and in the post-translational modification of signaling proteins. It has been reported that non-bisphosphonate FPPS inhibitors targeting its allosteric binding pocket are potentially important for the development of promising anti-cancer drugs.
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Characterization of saccharide using high fluorescent 5-(((2-(carbohydrazino)methyl)thio)acetyl)-aminofluorescein tag by Capillary-HPLC-LIF and MALDI-TOF-MS.
Talanta
PUBLISHED: 06-15-2013
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The new approach to one-step derivatization of saccharide with 5-(((2-(carbohydrazino)methyl)thio)acetyl)-aminofluorescein (C356) was described. In this approach, high fluorescent C356 was applied to label saccharide to enhance the response of derivative saccharide and high sensitive capillary high performance liquid chromatography with laser-induced fluorescence (Capillary-HPLC-LIF) associated with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used to characterize C356 labeled saccharide. The effect of derivatization conditions was evaluated and discussed. The limit of detection (LOD) of neutral saccharide in our method attained the level of femtomolar. As a result, this method could be successfully applied to determine the structure of N-glycans of glycoprotein.
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Characterization of depth-related changes in bacterial community compositions and functions of a paddy soil profile.
FEMS Microbiol. Lett.
PUBLISHED: 06-07-2013
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Depth-related changes in bacterial community structures and functions were analyzed in a paddy soil profile using denaturing gradient gel electrophoresis (DGGE) and a metabolic profiling technique (BIOLOG ECO plates). Canonical correspondence analysis (CCA) was used to analyze the correlations between the relative abundance of bacterial groups and soil-available elements. DGGE and sequencing analysis revealed 12 classes and one unknown bacterial group. At the family level, Comamonadaceae and Moraxellaceae dominated through the soil profile, while Acidobacteriaceae and Nitrospiraceae dominated in the deepest layer. In addition, Streptococcaceae dominated and was only observed in the deeper layers. Metabolic profiles revealed the greatest carbon source utilization capacity in the surface layer, and no significant differences between upper and deeper soil layers. The carbon sources utilized by microorganisms were different among the different layers. CCA indicated that soil-available Mn, Ca, Cu, Al, and K concentrations were positively correlated with the relative abundance of Comamonadaceae, Moraxellaceae, Streptococcaceae, Microbacteriaceae, Nocardioidaceae, and Nitrospiraceae in the profile. The results showed that the paddy soil profile harbored diverse bacterial communities and experienced depth-related changes in community structure and carbon source utilization. The bacterial communities and functions might be shaped by the soil edaphic characteristics along the soil profile.
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The role of positive charges on G-quadruplex binding small molecules: learning from bisaryldiketene derivatives.
Biochim. Biophys. Acta
PUBLISHED: 05-27-2013
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G-quadruplexes are promising therapeutic targets for small molecules. In general, the introduction of steady positive charges through the in situ alkylation of nitrogen atoms within potential G-quadruplex ligands can significantly improve their quadruplex binding and stabilization abilities. However, our previous studies on bisaryldiketene derivatives showed that the derivative M4, whose central piperidone moiety is quaternized, exhibits a poor G-quadruplex stabilization ability.
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Stray light analysis and suppression of panoramic annular lens.
Opt Express
PUBLISHED: 05-15-2013
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A new stray light analysis method and some suppression principles of panoramic annular lens (PAL) are introduced in this paper. The proposed method is to find stray light paths which are caused by ray splitting on two refractive surfaces of the PAL block and then cut them off. Following this principle, the stray light paths can be eliminated in the design progress by adding specific merit functions into the optical software. The methods to reduce scatter, diffraction and other stray light are also proposed. A new PAL with a field of view (FOV) of 30° ~ 100° × 360° is designed. The stray light is suppressed more than 80% compared with a similar conventional PAL. The stray light path analysis method also can be used in other catadioptric optics.
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Synthesis and biological evaluation of benzo[a]phenazine derivatives as a dual inhibitor of topoisomerase I and II.
Org. Biomol. Chem.
PUBLISHED: 05-08-2013
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Topoisomerases (Topo I and Topo II) are very important players in DNA replication, repair, and transcription, and are a promising class of antitumor target. In present study, a series of benzo[a]phenazine derivatives with alkylamino side chains at C-5 were designed, synthesized, and their biological activities were evaluated. Most of derivatives showed good antiproliferative activity with a range of IC50 values of 1-10 ?M on the four cancer cell lines HeLa, A549, MCF-7, and HL-60. Topoisomerase-mediated DNA relaxation assay results showed that derivatives could effectively inhibit the activity of both Topo I and Topo II, and the structure-activity relationship studies indicated the importance of introducing an alkylamino side chain. Further mechanism studies revealed that the compounds could stabilize the Topo I-DNA cleavage complexes and inhibit the ATPase activity of hTopo II, indicating that they are a rare class of dual topoisomerase inhibitors by acting as Topo I poisons and Topo II catalytic inhibitors. Moreover, flow cytometric analysis and caspase-3/7 activation assay showed that this class of compounds could induce apoptosis of HL-60 cells.
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Polybrominated diphenyl ethers in farmland soils: source characterization, deposition contribution and apportionment.
Sci. Total Environ.
PUBLISHED: 03-17-2013
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Polybrominated diphenyl ethers (PBDEs), a group of persistent organic pollutants (POPs), are caused for concern recently due to their adverse health effects and environmental ubiquity. In this study, atmospheric and soil PBDE levels in Taizhou, one of the largest WEEE dismantling areas in the world, were measured, ranging from 884 to 2791 pg m(-3) with an average of 1968 pg m(-3) for atmosphere and 2.96 to 200 ng g(-1)dry weight (dw) with the mean of 65.2 ng g(-1)dw for farmland soils, respectively. The close connection between soil PBDE accumulation and atmospheric deposition was also revealed by the estimation of the annual PBDE deposition flux (3.1 ± 0.9 mg m(-2)a(-1)) and the similarity between deposited congener pattern and soil congener profile. Positive matrix factorization (PMF) was conducted to extract possible sources of farmland soil PBDEs and to calculate their contributions. Based on the measured source profiles of PBDE-related activities, five sources were identified representing WEEE dumping, WEEE dismantling, WEEE open burning, residential waste dismantling, and residential waste open burning. WEEE-related recycling activities contributed primary percentage (52%) to farmland soil PBDE concentration, and open burning was an important pathway for PBDEs entering the environment.
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G-Quadruplex conformational change driven by pH variation with potential application as a nanoswitch.
Biochim. Biophys. Acta
PUBLISHED: 03-14-2013
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G-Quadruplex is a highly polymorphic structure, and its behavior in acidic condition has not been well studied.
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Aggressive hepatectomy for the curative treatment of bilobar involvement of type IV-A bile duct cyst.
Ann. Surg.
PUBLISHED: 03-13-2013
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To analyze the risk and benefit of aggressive hepatectomy for the curative treatment of bilobar bile duct cysts (BDCs) of type IV-A.
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Syntheses and evaluation of novel isoliquiritigenin derivatives as potential dual inhibitors for amyloid-beta aggregation and 5-lipoxygenase.
Eur J Med Chem
PUBLISHED: 03-06-2013
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A series of new isoliquiritigenin (ISL) derivatives were synthesized and evaluated as dual inhibitors for amyloid-beta (A?) aggregation and 5-lipoxygenase (5-LO). It was found that all these synthetic compounds inhibited A? (1-42) aggregation effectively with their IC?? values ranged from 2.2 ± 1.5 ?M to 23.8 ± 2.0 ?M. These derivatives also showed inhibitory activity to 5-LO with their IC50 values ranged from 6.1 ± 0.1 ?M to 35.9 ± 0.3 ?M. Their structure-activity relationships (SAR) and mechanisms of inhibitions were studied. This study provided potentially important information for further development of ISL derivatives as multifunctional agents for Alzheimers disease (AD) treatment.
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Expression analysis of LeNHX1 gene in mycorrhizal tomato under salt stress.
J. Microbiol.
PUBLISHED: 03-02-2013
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The plant growth, stem sap flow, Na(+) and Cl(-) content, and the expression of vacuolar Na(+)/H(+) antiporter gene (LeNHX1) in the leaves and roots of tomato under different NaCl stresses (0.5% and 1%) were studied to analyze the effect of arbuscular mycorrhizal fungi (AMF) on Na(+) and Cl(-) accumulation and ion exchange. The results showed that arbuscular mycorrhizal (AM) plant growth and stem sap flow increased and salt tolerance improved, whereas Na(+) and Cl(-) accumulated. Na(+) significantly decreased, and no significant decline was detected in Cl(-) content after AMF inoculation compared with the non-AM plants. The LeNHX1 gene expression was induced in the AM and non-AM plants by NaCl stress. However, AMF did not improve the LeNHX1 level, and low expression was observed in the AM tomato. Hence, the mechanism that reduced the Na(+) damage to tomato induced by AMF has little relation to LeNHX1, which can export Na(+) from the cytosol to the vacuole across the tonoplast.
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Oxygen insertion of o-quinone under catalytic hydrogenation conditions.
Org. Lett.
PUBLISHED: 03-01-2013
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An oxygen-insertion reaction that transforms an o-quinone and a conjugated ?-diketone substrate into an anhydride product or derivative under catalytic hydrogenation conditions is reported. The experiments and computations indicate that the oxygen insertion proceeds via a radical mechanism mediated by an acetoxyl radical.
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Increased circulating Th17 cells after transarterial chemoembolization correlate with improved survival in stage III hepatocellular carcinoma: a prospective study.
PLoS ONE
PUBLISHED: 02-27-2013
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Transarterial chemoembolization (TACE) has therapeutic effects in patients with unresectable hepatocellular carcinoma (HCC), but its impact on the cellular immune response during disease progression is largely unknown. Here we conducted a prospective study to evaluate the effect of TACE on immune status and to identify prognostic immune markers governing treatment success. In this study, 51 stage III HCC patients, 28 stage I HCC patients (TNM classification) and 20 healthy donors were enrolled. Flow cytometry and cytometric bead array were used to evaluate the circulating immune cell subsets, including CD4(+) T cells (Th1, Th17 and Treg cells), CD8(+) T cells, NK cells, and NKT cells, and plasma cytokines before TACE and 30 days after TACE. Interestingly, among those immune parameters, the frequency of circulating Th17 cells was higher in stage III HCC patients than in stage I HCC patients (P?=?0.015) and healthy donors (P<0.001). Moreover, an increased frequency of circulating Th17 cells was observed 30 days after TACE (Th17 D30 ) compared with the baseline level (P?=?0.036). Kaplan-Meier analysis demonstrated that Th17 D30 was positively associated with overall survival (OS; P?=?0.007) and time to progression (TTP; P?=?0.009). Multivariate Cox analysis revealed that Th17 D30 was an independent prognostic factor for OS (HR?=?0.317, P?=?0.032) and TTP (HR?=?0.304, P?=?0.010). These results provide a potential prognostic marker for stage III HCC patients undergoing TACE and may be useful for identifying patients who can benefit from adjuvant immunotherapies.
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Design, synthesis and biological evaluation of novel mansonone E derivatives prepared via CuAAC click chemistry as topoisomerase II inhibitors.
Eur J Med Chem
PUBLISHED: 02-26-2013
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Two series of novel C-9 chloro- and bromo-substituted mansonone E derivatives with triazole moieties at the C-3 position were prepared by using copper-catalysed azide-alkyne cycloaddition click chemistry. These compounds were found as potent inhibitors of topoisomerase II (Topo II) and topoisomerase I (Topo I). The Topo II-mediated pBR322 DNA relaxation and cleavage assay showed that the derivatives might act as catalytic inhibitors. Their cytotoxic activities against A549, HL-60, K562 and HeLa cells were evaluated, indicating that these compounds were potent antitumour agents. Their structure activity relationships and molecular docking study revealed that the substituents of the triazole were particularly important for cytotoxicity.
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Selenoprotein K is required for palmitoylation of CD36 in macrophages: implications in foam cell formation and atherogenesis.
J. Leukoc. Biol.
PUBLISHED: 02-26-2013
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Selk is an ER transmembrane protein important for calcium flux and macrophage activation, but its role in foam cell formation and atherosclerosis has not been evaluated. BMDMs from Selk(-/-) mice exhibited decreased uptake of modLDL and foam cell formation compared with WT controls, and the differences were eliminated with anti-CD36 blocking antibody. CD36 expression was decreased in TNF-?-stimulated Selk(-/-) BMDMs compared with WT controls. Fluorescence microscopy revealed TNF-?-induced clustering of CD36 in WT BMDMs indicative of lipid raft localization, which was absent in Selk(-/-) BMDMs. Fractionation revealed lower levels of CD36 reaching lipid rafts in TNF-?-stimulated Selk(-/-) BMDMs. Immunoprecipitation showed that Selk(-/-) BMDMs have decreased CD36 palmitoylation, which occurs at the ER membrane and is crucial for stabilizing CD36 expression and directing its localization to lipid rafts. To assess if this phenomenon had a role in atherogenesis, a HFD was fed to irradiated Ldlr(-/-) mice reconstituted with BM from Selk(-/-) or WT mice. Selk was detected in aortic plaques of controls, particularly in macrophages. Selk(-/-) in immune cells led to reduction in atherosclerotic lesion formation without affecting leukocyte migration into the arterial wall. These findings suggest that Selk is important for stable, localized expression of CD36 in macrophages during inflammation, thereby contributing to foam cell formation and atherogenesis.
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Dyella jiangningensis sp. nov., a ?-proteobacterium isolated from the surface of potassium-bearing rock.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 02-22-2013
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A Gram-stain-negative, aerobic, motile with one polar flagellum ?-proteobacterium, designated strain SBZ3-12(T), was isolated from surfaces of weathered potassic trachyte. Phylogenetic analysis of this strain based on 16S rRNA gene sequences showed that it was most closely related to Dyella japonica XD53(T) (97.9% 16S rRNA gene sequence similarity), Dyella terrae JS14-6(T) (97.7%), Dyella soli JS12-10(T) (97.5%) and Dyella koreensis BB4(T) (97.0%). The DNA G+C content of strain SBZ3-12(T) was 64.0 mol%. In addition, iso-C(17:1)?9c, iso-C(15:0) and iso-C(16:0) were the major cellular fatty acids and ubiquinone Q-8 was the predominant respiratory quinone. The low DNA-DNA relatedness values between strain SBZ3-12(T) and recognized species of the genus Dyella and the many phenotypic properties supported the classification of strain SBZ3-12(T) as a representative of a novel species of the genus Dyella, for which the name Dyella jiangningensis sp. nov. is proposed. The type strain is SBZ3-12(T) (?=CCTCC AB 2012160(T)?=KACC 16539(T)?=DSM 26119(T)).
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Glioblastoma stem cells generate vascular pericytes to support vessel function and tumor growth.
Cell
PUBLISHED: 02-11-2013
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Glioblastomas (GBMs) are highly vascular and lethal brain tumors that display cellular hierarchies containing self-renewing tumorigenic glioma stem cells (GSCs). Because GSCs often reside in perivascular niches and may undergo mesenchymal differentiation, we interrogated GSC potential to generate vascular pericytes. Here, we show that GSCs give rise to pericytes to support vessel function and tumor growth. In vivo cell lineage tracing with constitutive and lineage-specific fluorescent reporters demonstrated that GSCs generate the majority of vascular pericytes. Selective elimination of GSC-derived pericytes disrupts the neovasculature and potently inhibits tumor growth. Analysis of human GBM specimens showed that most pericytes are derived from neoplastic cells. GSCs are recruited toward endothelial cells via the SDF-1/CXCR4 axis and are induced to become pericytes predominantly by transforming growth factor ?. Thus, GSCs contribute to vascular pericytes that may actively remodel perivascular niches. Therapeutic targeting of GSC-derived pericytes may effectively block tumor progression and improve antiangiogenic therapy.
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3D-QSAR studies of azaoxoisoaporphine, oxoaporphine, and oxoisoaporphine derivatives as anti-AChE and anti-AD agents by the CoMFA method.
J. Mol. Graph. Model.
PUBLISHED: 02-04-2013
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In the present study, a series of novel azaoxoisoaporphine derivatives were reported and their inhibitory activities toward acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and A? aggregation were evaluated. The new compounds remained high inhibitory potency on A? aggregation, with inhibitory activity from 29.42% to 89.63% at a concentration of 10?M, but had no action on AChE or BuChE, which was very different from our previously reported oxoaporphine and oxoisoaporphine derivatives. By 3D-QSAR studies, we constructed a reliable CoMFA model (q(2)=0.856 and r(2)=0.986) based on the inhibitory activities toward AChE and discovered key information on structure and anti-AChE activities among the azaoxoisoaporphine, oxoaporphine, and oxoisoaporphine derivatives. The model was further confirmed by the test-set validation (q(2)=0.873, r(2)=0.937, and slope k=0.902) and Y-randomization examination. The statistically significant and physically meaningful 3D-QSAR/CoMFA model provided better insight into understanding the inhibitory behaviors of those chemicals, which may provide useful information for the rational molecular design of azaoxoisoaporphine derivatives anti-AChE and anti-AD agents.
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Mechanistic studies for the role of cellular nucleic-acid-binding protein (CNBP) in regulation of c-myc transcription.
Biochim. Biophys. Acta
PUBLISHED: 02-02-2013
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Guanine-rich sequence of c-myc nuclease hypersensitive element (NHE) III1 is known to fold in G-quadruplex and subsequently serves as a transcriptional silencer. Cellular nucleic-acid-binding protein (CNBP), a highly conserved zinc-finger protein with multiple biological functions, could bind to c-myc NHE III1 region, specifically to the single strand G-rich sequence.
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Synthesis and evaluation of 7,8-dehydrorutaecarpine derivatives as potential multifunctional agents for the treatment of Alzheimers disease.
Eur J Med Chem
PUBLISHED: 01-31-2013
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A series of 7,8-dehydrorutaecarpine derivatives were synthesized and characterized as potential multifunctional agents for treatment of Alzheimers disease (AD). All of these synthetic compounds showed high acetylcholinesterase (AChE) inhibitory activity with IC50 values ranged from 0.60 to 196.7 nM, and good selectivity for AChE over butyrylcholinesterase (BuChE) (125- to 3225-fold). A Lineweaver-Burk plot and molecular modeling study indicated these compounds could bind to both catalytic active site and the peripheral anionic site of AChE. Besides, compounds showed higher activity of inhibiting AChE-induced amyloid-beta (A?) aggregation than curcumin, higher anti-oxidative activity than Trolox, and could also be good metal chelators. Considering their low cytotoxicity, our results indicated that these derivatives provide good templates for developing new multifunctional agents for AD treatment.
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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.