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Find video protocols related to scientific articles indexed in Pubmed.
Comparison of waveguide properties and Raman spectroscopic visualization of C and O ion implantation on LaAlO3 crystals.
Appl Opt
PUBLISHED: 11-18-2014
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LaAlO3 crystals were implanted by C ions and O ions at an energy of 6.0 MeV with a fluence of 1.5×1015??ions/cm2. The profiles of the guided modes were measured through prism coupling and end-face coupling methods with a 633 nm laser source. A nonleaky waveguide structure in the TM mode was fabricated by O ion implantation after a proper annealing treatment. Characteristics of the implanted C and O ions were compared. Some changes of the full width at half of the maximum and intensity of the Raman spectra were observed between the waveguide and substrate regions in LaAlO3 crystals. Thus, the Raman spectra can be used to visualize any damage or defects in the LaAlO3 crystals during the implantation process.
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Molecular electronic level alignment at weakly coupled organic film/metal interfaces.
ACS Nano
PUBLISHED: 10-10-2014
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Electronic level alignment at interfaces of molecular materials with inorganic semiconductors and metals controls many interfacial phenomena. How the intrinsic properties of the interacting systems define the electronic structure of their interface remains one of the most important problems in molecular electronics and nanotechnology that can be solved through a combination of surface science experimental techniques and theoretical modeling. In this article, we address this fundamental problem through experimental and computational studies of molecular electronic level alignment of thin films of C6F6 on noble metal surfaces. The unoccupied electronic structure of C6F6 is characterized with single molecule resolution using low-temperature scanning tunneling microscopy-based constant-current distance-voltage spectroscopy. The experiments are performed on several noble metal surfaces with different work functions and distinct surface-normal projected band structures. In parallel, the electronic structures of the quantum wells (QWs) formed by the lowest unoccupied molecular orbital state of the C6F6 monolayer and multilayer films and their alignment with respect to the vacuum level of the metallic substrates are calculated by solving the Schrödinger equation for a semiempirical one-dimensional (1D) potential of the combined system using input from density functional theory. Our analysis shows that the level alignment for C6F6 molecules bound through weak van der Waals interactions to noble metal surfaces is primarily defined by the image potential of metal, the electron affinity of the molecule, and the molecule surface distance. We expect the same factors to determine the interfacial electronic structure for a broad range of molecule/metal interfaces.
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[Regulatory effects of polyporus polysaccharide on the expressions of cytokines released from M1 macrophages].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 10-02-2014
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Objective To investigate the regulatory effects of polyporus polysaccharide (PPS) on mRNA expressions of interleukin 1? (IL-1?), tumor necrosis factor ? (TNF-?), inducible nitric oxide synthase (iNOS), transforming growth factor ? (TGF-?) and IL-10 in M1 macrophages. Methods RAW264.7 macrophages were randomly divided into five groups, negative control, M1 macrophayes, 50 ?g/mL PPS, 100 ?g/mL PPS, and 200 ?g/mL PPS. M1 macrophages was induced by interferon ? (IFN-?). Flow cytometry was subsequently used to examine the expressions of biomakers of M1 macrophages , such as CD16/CD32 and CD86. To observe the effects of PPS on M1 macrophages at graded levels, real-time PCR was performed to evaluate the mRNA expressions of IL-1?, IL-10, iNOS, TGF-? and TNF-?. Results The expressions of CD16/CD32 and CD86 in RAW264.7 macrophages significantly increased by IFN-?, as compared with the cells without IFN-? treatment. The mRNA levels of IL-1?, iNOS, IL-10, TGF-? and TNF-? were raised by 100 ?g/mL PPS at 3, 6, 9, 12 and 24 hours (P<0.01). Moreover, the mRNA expressions of these factors could be elevated by the 6 hour-treatment of PPS at different concentrations (P<0.01). Conclusion M1 macrophages of can be induced from RAW264.7 cells by stimulation of IFN-? alone. In addition, PPS can promote the mRNA expressions of IL-1?, iNOS, IL-10, TGF-? and TNF-? in M1 macrophages.
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Visible and near-infrared optical properties of a proton-implanted KTP waveguide.
Appl Opt
PUBLISHED: 08-05-2014
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In this work, the optical properties of potassium titanyl phosphate (KTP) waveguides in the visible and near-infrared region are reported. The KTP waveguides were fabricated using 550 keV proton implantation at room temperature, and the refractive index profiles of the implanted region in the visible and near-infrared region were reconstructed. The profiles of the guided modes were measured through the end-face coupling method with both 632.8 and 1539 nm laser sources and then compared with the simulation results using the beam propagation method. Optical transmission and Raman spectra in the original substrate and waveguide active region were measured to study microstructural changes. The propagation loss of the TM0-mode at 632.8 nm was also measured.
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Self-catalyzed carbon dioxide adsorption by metal-organic chains on gold surfaces.
ACS Nano
PUBLISHED: 07-30-2014
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Efficient capture of CO2 by chemical means requires a microscopic understanding of the interactions of the molecule–substrate bonding and adsorption-induced collective phenomena. By molecule-resolved imaging with scanning tunneling microscopy (STM), we investigate self-catalyzed CO2 adsorption on one-dimensional (1D) substrates composed of self-assembled metal–organic chains (MOCs) supported on gold surfaces. CO2 adsorption turns on attractive interchain interactions, which induce pronounced surface structural changes; the initially uniformly dispersed chains gather into close packed bundles, which are held together by highly ordered, single molecule wide CO2 ranks. CO2 molecules create more favorable adsorption sites for further CO2 adsorption by mediating the interchain attraction, thereby self-catalyzing their capture. The release of CO2 molecules by thermal desorption returns the MOCs to their original structure, indicating that the CO2 capture and release are reversible processes. The real space microscopic characterization of the self-catalyzed CO2 adsorption on 1D substrates could be exploited as platform for design of molecular materials for CO2 capture and reduction.
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First principles study of fluorine substitution on two-dimensional germanane.
J Phys Condens Matter
PUBLISHED: 07-29-2014
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Using first principles calculations with hybrid exchange-correlation functional, we investigate the electronic structure of germanane and fluorinated germanane. We find that the band gap of fluorinated germanane decreases with the increasing of fluorine coverage, regardless of fluorine distribution on the surface. Our results indicate that chemical functionalization could be used easily to control the band gap of the germanane from 1.55 eV (pure germanane) to 0.17 eV (fully fluorinated germanane). It also shows good potentiality as a photocatalytic material for water splitting, as well as a two-dimensional functional material for optoelectronic and sensing applications.
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Synthesis of Bi nanowire networks and their superior photocatalytic activity for Cr(vi) reduction.
Nanoscale
PUBLISHED: 07-17-2014
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Interconnected Bi nanowire networks were synthesized for the first time via a solvothermal route by using ethylene glycol (EG) as both a solvent and a reducing agent, and citric acid (CA) as a stabilizing agent at a molar ratio of CA/Bi(3+) = 5. Among various reaction conditions including the temperature, reaction time and precursor concentration, the molar ratio of CA/Bi(3+) was the dominant experimental parameter to influence the morphology and structures of the Bi crystals. Highly dispersed Bi microspheres and network-like Bi thick wires were obtained if the molar ratio of CA/Bi(3+) was changed to 2.5 and 10, respectively. As compared to other additives including trisodium citrate, cetyltrimethylammonium bromide (CTAB) and oxalic acid, good solubility of CA in EG together with its coordination effect played a crucial role in the formation of network-like Bi nanowires. The Bi nanowire networks exhibited excellent photocatalytic performance for Cr(vi) reduction. Cr(vi) was completely reduced to less toxic Cr(iii) after 8 min and 55 min of UV and visible-light irradiation, respectively.
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Multistimuli-responsive supramolecular assembly of cucurbituril/cyclodextrin pairs with an azobenzene-containing bispyridinium guest.
Chemistry
PUBLISHED: 07-02-2014
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A linear supramolecular architecture was successfully constructed by the inclusion complexation of ?-cyclodextrin with azobenzene and the host-stabilized charge-transfer interaction of naphthalene and a bispyridinium guest with cucurbit[8]uril in water, which was comprehensively characterized by (1) H?NMR spectroscopy, UV/Vis absorption, fluorescence, circular dichroism spectroscopy, dynamic laser scattering, and microscopic observations. Significantly, because it benefits from the photoinduced isomerization of the azophenyl group and the chemical reduction of bispyridinium moiety with noncovalent connections, the assembly/disassembly process of this supramolecular nanostructure can be efficiently modulated by external stimuli, including temperature, UV and visible-light irradiation, and chemical redox.
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Notch signaling functions in lymphatic valve formation.
Development
PUBLISHED: 06-12-2014
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Collecting lymphatic ducts contain intraluminal valves that prevent backflow. In mice, lymphatic valve morphogenesis begins at embryonic day 15.5 (E15.5). In the mesentery, Prox1 expression is high in valve-forming lymphatic endothelial cells, whereas cells of the lymphatic ducts express lower levels of Prox1. Integrin ?9, fibronectin EIIIA, Foxc2, calcineurin and the gap junction protein Cx37 are required for lymphatic valve formation. We show that Notch1 is expressed throughout the developing mesenteric lymphatic vessels at E16.5, and that, by E18.5, Notch1 expression becomes highly enriched in the lymphatic valve endothelial cells. Using a Notch reporter mouse, Notch activity was detected in lymphatic valves at E17.5 and E18.5. The role of Notch in lymphatic valve morphogenesis was studied using a conditional lymphatic endothelial cell driver either to delete Notch1 or to express a dominant-negative Mastermind-like (DNMAML) transgene. Deletion of Notch1 led to an expansion of Prox1(high) cells, a defect in Prox1(high) cell reorientation and a decrease in integrin ?9 expression at sites of valve formation. Expression of DNMAML, which blocks all Notch signaling, resulted in a more severe phenotype characterized by a decrease in valves, failure of Prox1(high) cells to cluster, and rounding of the nuclei and decreased fibronectin-EIIIA expression in the Prox1(high) cells found at valve sites. In human dermal lymphatic endothelial cells, activation of Notch1 or Notch4 induced integrin ?9, fibronectin EIIIA and Cx37 expression. We conclude that Notch signaling is required for proper lymphatic valve formation and regulates integrin ?9 and fibronectin EIIIA expression during valve morphogenesis.
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Risk determinants associated with early childhood caries in Uygur children: a preschool-based cross-sectional study.
BMC Oral Health
PUBLISHED: 06-11-2014
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The prevalence of early childhood caries (ECC) varies with geographical region and population. The Uygur people, one of 55 officially recognized ethnic minorities in China, have a population of 10,069,346. We performed a preschool-based cross-sectional study of 670 Uygur children from the southern region of Xinjiang, China, to investigate the prevalence and severity of ECC and to identify factors related to the dental health condition of this population.
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A pilot study of conically graded chitosan-gelatin hydrogel/PLGA scaffold with dual-delivery of TGF-?1 and BMP-2 for regeneration of cartilage-bone interface.
J. Biomed. Mater. Res. Part B Appl. Biomater.
PUBLISHED: 05-20-2014
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Repair of cartilage-bone interface tissue remains challenging, because it combines different cell types and gradients of composition and properties. To enable simultaneous regeneration of bone, cartilage, and especially their interface, a conically graded scaffold of chitosan-gelatin hydrogel/poly(l-lactide-co-glycolide) (PLGA) was facilely prepared in the study. The chitosan-gelatin hydrogel containing transforming growth factor ?1 (TGF-?1) was used for chondrogenesis, while the PLGA scaffold loading bone morphogenetic protein-2 (BMP-2) for osteogenesis. The conically graded transition from the hydrogel to PLGA scaffold and graded variation in amount of growth factors from TGF-?1 to BMP-2 benefited the cartilage-bone interface reconstruction. The graded scaffold exhibited spatio-temporal delivery of TGF-?1 and BMP-2. Preliminary results of in vitro cell culture demonstrated that the hydrogel and PLGA phases could promote bone marrow mesenchymal stem cells toward chondrogenic and osteogenic differentiation, respectively. From the result of the pilot in vivo experiment, it showed that the regenerated hyaline-like cartilage surface and subchondral bone excellently integrated with the native tissues were found by using the TGF-?1 and BMP-2 double-loaded hydrogel/PLGA graded scaffold via H&E and immunohistochemical stainings of collagen I, collagen II, and osteocalcin at 2 months. The obtained preliminary experiment results showed that the hydrogel/PLGA graded scaffold combining multiphasic composition and spatial dual growth-factor delivery would be useful for cartilage-bone interface tissue defect repair. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2014.
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MiR-214 and N-ras regulatory loop suppresses rhabdomyosarcoma cell growth and xenograft tumorigenesis.
Oncotarget
PUBLISHED: 05-10-2014
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Rhabdomyosarcoma (RMS) is a childhood malignant soft tissue cancer that is derived from myogenic progenitors trapped in a permanent mode of growth. Here, we report that miR-214 is markedly down-regulated in human RMS cell lines. Although not required for embryogenesis in mice, miR-214 suppresses mouse embryonic fibroblast (MEF) proliferation. When re-introduced into RD cells, a line of human embryonal RMS cells, miR-214 showed inhibition of tumor cell growth, induction of myogenic differentiation and apoptosis, as well as suppression of colony formation and xenograft tumorigenesis. We show that in the absence of miR-214, expression of proto-oncogene N-ras is markedly elevated in miR-214(-/-) MEFs, and manipulations of miR-214 levels using microRNA mimics or inhibitor in RD cells reciprocally altered N-ras expression. We further demonstrate that forced expression of N-ras from a cDNA that lacks its 3'-untranslated region neutralized the pro-myogenic and anti-proliferative activities of miR-214. Finally, we show that N-ras is a conserved target of miR-214 in its suppression of xenograft tumor growth, and N-ras expression is up-regulated in xenograft tumor models as well as actual human RMS tissue sections. Taken together, these data indicate that miR-214 is a bona fide suppressor of human RMS tumorigensis.
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Takayasu's arteritis misdiagnosed as mediastinal malignant lymphoma: a case report and review of the literature.
J Thorac Dis
PUBLISHED: 04-09-2014
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Takayasu's arteritis (TA) is a rare chronic large-vessel vasculitis. The early diagnosis is difficult, because of lack of characteristic clinical manifestations. In this paper, we reported a TA case of young female was misdiagnosed as mediastinal malignant lymphoma and mediastinoscope biopsy was performed. The biopsy result demonstrated that thickened tissue adjacent to the aortic arch pathological presentations were in accord with TA. Glucocorticoid was administrated and the condition was greatly improved after treatment. Therefore, we reported this case and review of the pertinent literature in order to help clinicians improve the understanding of TA and PET/CT manifestations of TA at early phase to realize the early diagnosis and treatment of TA, finally reducing the hazards.
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Synthesis and biological activity of anthrapyrazoles derivatives as potential antitumor agents.
Med Chem
PUBLISHED: 04-04-2014
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We have synthesized a series of anthrapyrazoles derivatives. The biological results indicated that these derivatives exhibited potent in vitro cytotoxicity against different cancer cell lines (human hepatocellular carcinoma HepG2 and BEL-7402, human colonic carcinoma HCT-116 and HT-29) and drug-resistant human hepatoma cell line (SMMC-7721). Among them, the polyamine-based anthrapyrazole derivatives 4c and 4f-g showed superior cytotoxicity than that of Mitoxantrone both on cancer cell lines and the drug-resistant subline. However, the DNA relaxation assay revealed that they had insignificant topoisomerase II inhibition. These results clearly indicate that polyamine side chains will have a profound effect on the cytotoxicity of anthrapyrazoles derivatives.
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The complex jujube genome provides insights into fruit tree biology.
Nat Commun
PUBLISHED: 03-21-2014
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The jujube (Ziziphus jujuba Mill.), a member of family Rhamnaceae, is a major dry fruit and a traditional herbal medicine for more than one billion people. Here we present a high-quality sequence for the complex jujube genome, the first genome sequence of Rhamnaceae, using an integrated strategy. The final assembly spans 437.65?Mb (98.6% of the estimated) with 321.45?Mb anchored to the 12 pseudo-chromosomes and contains 32,808 genes. The jujube genome has undergone frequent inter-chromosome fusions and segmental duplications, but no recent whole-genome duplication. Further analyses of the jujube-specific genes and transcriptome data from 15 tissues reveal the molecular mechanisms underlying some specific properties of the jujube. Its high vitamin C content can be attributed to a unique high level expression of genes involved in both biosynthesis and regeneration. Our study provides insights into jujube-specific biology and valuable genomic resources for the improvement of Rhamnaceae plants and other fruit trees.
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HIV risk and prevention behaviors in men who have sex with men and women: a respondent-driven sampling study in Shenzhen, China.
AIDS Behav
PUBLISHED: 03-01-2014
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Men who have sex with men and women (MSMW) may expand the HIV epidemic from men who have sex with men to the female population. From a respondent-driven sampling survey in Shenzhen, China, we quantified the burden of HIV/syphilis and studied patterns of risk and prevention behaviors in 107 MSMW, and compared these with those of 542 men who have sex with men only (MSM-only). HIV prevention behaviors and consistent condom use with male partners did not differ between the two groups. However, HIV risk behaviors were more common among MSMW than MSM-only. Moreover, among MSMW, the HIV prevalence was as high as 6 % and consistent condom use was extremely low with female partners in MSMW. We conclude that there is risk of HIV transmission from MSMW to the female population. Special efforts are needed to convince MSMW they should refrain from HIV risk behaviors.
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A Comparison Between Respondent-Driven Sampling and Time-Location Sampling Among Men Who Have Sex with Men in Shenzhen, China.
Arch Sex Behav
PUBLISHED: 02-14-2014
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Men who have sex with men (MSM) are a key population for HIV control and prevention in China. It is difficult to acquire representative samples of this hidden population. Respondent-driven sampling (RDS), based on peer referral, and time-location sampling (TLS) based on random selection of venue-day-time periods, are among the most commonly used sampling methods. However, differences in HIV-related characteristics of MSM recruited by these two methods have not been fully evaluated. We compared sociodemographics, risk behaviors, utilization of HIV-related intervention services, and HIV/syphilis infection rates between samples of 621 RDS MSM and 533 TLS MSM in Shenzhen, China in 2010. We found that the HIV prevalence was comparable in RDS and TLS MSM. TLS recruited larger proportions of more marginalized MSM than RDS: MSM recruited by TLS were older, less educated and more likely to be migrants (without Shenzhen hukou registration), to be non-gay identified and to engage in risky sexual behaviors. On the other hand, MSM recruited by TLS were more likely to have been covered by HIV-related intervention services. To conclude, in Shenzhen, TLS is more effective to reach the marginalized population of MSM. But because TLS can only reach MSM who physically attend venues and HIV-related intervention services are already commonly available at gay venues in Shenzhen, RDS is more informative for allocating prevention efforts than TLS. Furthermore, researchers and public health authorities should take into account the different sample compositions of RDS and TLS and apply sampling methods consistently when evaluating trends over time.
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A novel HCN4 mutation, G1097W, is associated with atrioventricular block.
Circ. J.
PUBLISHED: 01-31-2014
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?Loss-of-function mutations in the HCN4 gene have been shown to be associated with sinus dysfunction, but there are no reports on HCN4-mediated atrioventricular (AV) block. A novel missense HCN4 mutation G1097W was identified in a 69 year-old Japanese male with AV block, and we characterized the functional consequences of If-like channels reconstituted with the heterozygous HCN4 mutation.
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Gene expression profiling of CD4? T cells in treatment-naive HIV, HCV mono- or co-infected Chinese.
Virol. J.
PUBLISHED: 01-29-2014
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Because of the shared transmission routes, co-infection with human immunodeficiency virus (HIV) and hepatitis C virus (HIV) is very common. Accumulated clinical evidence showed that one could alter the infectious course of the other virus in HIV and HCV co-infected individuals. However, little is known on the molecular basis of HIV/HCV interactions and their modulations on hosts.
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Synthesis and antifungal activity of 7-methyl-7-hydroxy-2,3-benzo[c]octa-1,6-olide.
J Asian Nat Prod Res
PUBLISHED: 01-25-2014
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The racemic 7-methyl-7-hydroxy-2,3-benzo[c]octa-1,6-olide, the analog of natural product (6R)-3,7-dimethyl-7-hydroxy-2-octen-1,6-olide, was totally synthesized using easily available (E)-2-(2-carboxyvinyl)benzoic acid as a raw material in nine-step reactions including three key steps of Wittig reaction, epoxidation, and cyclization, with an overall yield of 10.3%. The bioassay results showed that ( ± )-2 exhibited stronger antifungal activity than the natural product ( ± )-1 and (R)-1 against Alternaria solani with an EC?? value of 27.36 ?g/ml.
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In vitro inhibition of the replication of classical swine fever virus by porcine Mx1 protein.
Antiviral Res.
PUBLISHED: 01-24-2014
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Classical swine fever virus (CSFV) is the causative pathogen of classical swine fever (CSF), a highly contagious disease of swine. Mx proteins are interferon-induced dynamin-like GTPases present in all vertebrates with a wide range of antiviral activities. Although Zhao et al. (2011) have reported that human MxA can inhibit CSFV replication, whether porcine Mx1 (poMx1) has anti-CSFV activity remains unknown. In this study, we generated a cell line designated PK-15/EGFP-poMx1 which expressed porcine Mx1 protein constitutively, and we observed that the proliferation of progeny virus in this cell line was significantly inhibited as measured by virus titration, indirect immune fluorescence assay, Q-PCR and Western blot. Furthermore, when PTD-poMx1 fusion protein expressed in Escherichia coli (Zhang et al., 2013) was used to treat CSFV-infected PK-15 cells, the results showed that PTD-poMx1 inhibited CSFV replication in a dose-dependent manner. Additionally, the proliferation of progeny virus was inhibited as measured by virus titration and Q-PCR. Overall, the results demonstrated that poMx1 effectively inhibited CSFV replication, suggesting that poMx1 may be a valuable therapeutic agent against CSFV infection.
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Detection and complete genome characterization of human enterovirus 118 from children with acute respiratory disease in China.
Virus Genes
PUBLISHED: 01-23-2014
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Enterovirus 118 (EV-118) within species HEV-C was detected in two 5-month-old boys with pneumonia in China. The EV-118 from both cases was genetically closer to ISR10 strain from Israel than to PER161 strain from Peru based on VP1 gene sequences. The complete genome of the detected EV-118 consists of 7,360 nucleotides, excluding the poly (A) tail. The 5'UTR contains 669 nucleotides, and 3'UTR consists of 73 nucleotides. A single open reading frame from base 670 to 7,287 that encodes a 2,206-amino-acid polyprotein was featured. The base composition of the full genome is 27.9 % A, 24.2 % C, 24.4 % G, and 23.6 % U. Phylogenetic analysis of the full genome sequences illustrated EV-118 was genetically closer to EV-109 and EV-105, and the Chinese strain differed from Peru strain. In summary, the presence of EV-118 was confirmed in pediatric pneumonia cases and complete genome sequences were identified for the first time in China.
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Carboxymethyl chitosan-folic acid-conjugated Fe3O4@SiO2 as a safe and targeting antitumor nanovehicle in vitro.
Nanoscale Res Lett
PUBLISHED: 01-22-2014
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A synthetic method to prepare a core-shell-structured Fe3O4@SiO2 as a safe nanovehicle for tumor cell targeting has been developed. Superparamagnetic iron oxide is encapsulated inside nonporous silica as the core to provide magnetic targeting. Carboxymethyl chitosan-folic acid (OCMCS-FA) synthesized through coupling folic acid (FA) with OCMCS is then covalently linked to the silica shell and renders new and improved functions because of the original biocompatible properties of OCMCS and the targeting efficacy of FA. Cellular uptake of the nanovehicle was assayed by confocal laser scanning microscope using rhodamine B (RB) as a fluorescent marker in HeLa cells. The results show that the surface modification of the core-shell silica nanovehicle with OCMCS-FA enhances the internalization of nanovehicle to HeLa cells which over-express the folate receptor. The cell viability assay demonstrated that Fe3O4@SiO2-OCMCS-FA nanovehicle has low toxicity and can be used as an eligible candidate for drug delivery system. These unique advantages make the prepared core-shell nanovehicle promising for cancer-specific targeting and therapy.
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CS5931, a novel polypeptide in Ciona savignyi, represses angiogenesis via inhibiting vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs).
Mar Drugs
PUBLISHED: 01-09-2014
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CS5931 is a novel polypeptide from Ciona savignyi with anticancer activities. Previous study in our laboratory has shown that CS5931 can induce cell death via mitochondrial apoptotic pathway. In the present study, we found that the polypeptide could inhibit angiogenesis both in vitro and in vivo. CS5931 inhibited the proliferation, migration and formation of capillary-like structures of HUVECs (Human Umbilical Vein Endothelial Cell) in a dose-dependent manner. Additionally, CS5931 repressed spontaneous angiogenesis of the zebrafish vessels. Further studies showed that CS5931 also blocked vascular endothelial growth factor (VEGF) production but without any effect on its mRNA expression. Moreover, CS5931 reduced the expression of matrix metalloproteinases (MMP-2 and MMP-9) both on protein and mRNA levels in HUVEC cells. We demonstrated that CS5931 possessed strong anti-angiogenic activity both in vitro and in vivo, possible via VEGF and MMPs. This study indicates that CS5931 has the potential to be developed as a novel therapeutic agent as an inhibitor of angiogenesis for the treatment of cancer.
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Nonnuclear nearly free electron conduction channels induced by doping charge in nanotube-molecular sheet composites.
J Phys Chem A
PUBLISHED: 01-09-2014
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Nearly free electron (NFE) states with density maxima in nonnuclear (NN) voids may have remarkable electron transport properties ranging from suppressed electron-phonon interaction to Wigner crystallization. Such NFE states, however, usually exist near the vacuum level, which makes them unsuitable for transport. Through first principles calculations on nanocomposites consisting of carbon nanotube (CNT) arrays sandwiched between boron nitride (BN) sheets, we describe a stratagem for stabilizing the NN-NFE states to below the Fermi level. By doping the CNTs with negative charge, we establish Coulomb barriers at CNTs walls that, together with the insulating BN sheets, define the transverse potentials of one-dimensional (1D) transport channels, which support the NN-NFE states.
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Human leukocyte antigen-DRB1*1501 and DQB1*0602 alleles are cervical cancer protective factors among Uighur and Han people in Xinjiang, China.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Human papillomavirus (HPV) infection is a major risk factor for cervical cancer. However, only some high risk human papillomavirus (HR-HPV)-infected women progress to cervical cancer, host immunogenetic factors human leukocyte antigen (HLA) may account for viral antigens presenting individually or together in the progression to cervical cancer. This study examined the association between the development of invasive cervical cancer (ICC) and the determinant factors including HLA-DRB1*1501 and DQB1*0602, HR-HPV infection among Chinese Uighur and Han populations. Blood samples, cervical swabs and biopsies were obtained from 287 patients with ICC (192 Uighurs and 95 Hans) and 312 healthy controls (218 Uighurs and 94 Hans). HPV DNA was detected by PCR and HLA-DRB1*1501 and DQB1*0602 alleles were performed using PCR-SSP method. HPV16 infection rates was significantly higher among Uighur and Han with ICC as compared to healthy controls (OR = 58.317; 95% CI: 39.663-85.744; OR = 33.778; 95% CI: 12.581-90.691; P < 0.05 for all). HLA-DRB1*1501 (OR = 0.305; 95% CI: 0.115-0.813; P < 0.05) and HLA-DRB1*1501-DQB1*0602 haplotype frequencies (OR = 0.274; 95% CI: 0.086-0.874; P < 0.05) were significantly reduced in Han ICC. The HLA-DQB1*0602 frequency significantly decreased among Uighur women with ICC (OR = 0.482; 95% CI: 0.325-0.716; P < 0.05). Similar tendencies were observed for DQB1*0602 with HPV16-positive ICC (OR = 0.550; 95% CI: 0.362-0.837; P < 0.05). This study suggests that HLA-DRB1*1501 and DQB1*0602 alleles may influence the immune response to HPV16 infection and decrease the risk of ICC among Uighurs and Hans in Xinjiang, China.
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Rapid SNP Discovery and a RAD-Based High-Density Linkage Map in Jujube (Ziziphus Mill.).
PLoS ONE
PUBLISHED: 01-01-2014
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Ziziphus Mill. (jujube), the most valued genus of Rhamnaceae, comprises of a number of economically and ecologically important species such as Z. jujuba Mill., Z. acidojujuba Cheng et Liu and Z. mauritiana Lam. Single nucleotide polymorphism (SNP) markers and a high-density genetic map are of great benefit to the improvement of the crop, mapping quantitative trait loci (QTL) and analyzing genome structure. However, such a high-density map is still absent in the genus Ziziphus and even the family Rhamnaceae. The recently developed restriction-site associated DNA (RAD) marker has been proven to be most powerful in genetic map construction. The objective of this study was to construct a high-density linkage map using the RAD tags generated by next generation sequencing.
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Optimization on condition of epigallocatechin-3-gallate (EGCG) nanoliposomes by response surface methodology and cellular uptake studies in Caco-2 cells.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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The major component in green tea polyphenols, epigallocatechin-3-gallate (EGCG), has been demonstrated to prevent carcinogenesis. To improve the effectiveness of EGCG, liposomes were used as a carrier in this study. Reverse-phase evaporation method besides response surface methodology is a simple, rapid, and beneficial approach for liposome preparation and optimization. The optimal preparation conditions were as follows: phosphatidylcholine-to-cholesterol ratio of 4.00, EGCG concentration of 4.88 mg/mL, Tween 80 concentration of 1.08 mg/mL, and rotary evaporation temperature of 34.51°C. Under these conditions, the experimental encapsulation efficiency and size of EGCG nanoliposomes were 85.79%?±?1.65% and 180 nm?±?4 nm, which were close with the predicted value. The malondialdehyde value and the release test in vitro indicated that the prepared EGCG nanoliposomes were stable and suitable for more widespread application. Furthermore, compared with free EGCG, encapsulation of EGCG enhanced its inhibitory effect on tumor cell viability at higher concentrations.
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Interleukin-27 is differentially associated with HIV viral load and CD4+ T cell counts in therapy-naïve HIV-mono-infected and HIV/HCV-co-infected Chinese.
PLoS ONE
PUBLISHED: 01-01-2014
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Human Immunodeficiency Virus (HIV) infection and the resultant Acquired Immunodeficiency Syndrome (AIDS) epidemic are major global health challenges; hepatitis C virus (HCV) co-infection has made the HIV/AIDS epidemic even worse. Interleukin-27 (IL-27), a cytokine which inhibits HIV and HCV replication in vitro, associates with HIV infection and HIV/HCV co-infection in clinical settings. However, the impact of HIV and HCV viral loads on plasma IL-27 expression levels has not been well characterized. In this study, 155 antiretroviral therapy-naïve Chinese were recruited. Among them 80 were HIV- and HCV-negative healthy controls, 45 were HIV-mono-infected and 30 were HIV/HCV-co-infected. Plasma level HIV, HCV, IL-27 and CD4+ number were counted and their correlation, regression relationships were explored. We show that: plasma IL-27 level was significantly upregulated in HIV-mono-infected and HIV/HCV-co-infected Chinese; HIV viral load was negatively correlated with IL-27 titer in HIV-mono-infected subjects whereas the relationship was opposite in HIV/HCV-co-infected subjects; and the relationships between HIV viral loads, IL-27 titers and CD4+ T cell counts in the HIV mono-infection and HIV/HCV co-infection groups were dramatically different. Overall, our results suggest that IL-27 differs in treatment-naïve groups with HIV mono-infections and HIV/HCV co-infections, thereby providing critical information to be considered when caring and treating those with HIV mono-infection and HIV/HCV co-infection.
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Overweight and obesity among low-income Muslim Uyghur women in far western China: correlations of body mass index with blood lipids and implications in preventive public health.
PLoS ONE
PUBLISHED: 01-01-2014
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The pandemic of obesity is a global public health concern. Most studies on obesity are skewed toward high-income and urban settings and few covers low-income populations. This study focused on the prevalence of overweight and obesity and their correlations with blood lipids/metabolites/enzymes (bio-indicators) in a rural community typical of low-income in remote western China.
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Xp11 translocation renal cell carcinoma in adults: a clinicopathological and comparative genomic hybridization study.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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To study the clinicopathological and genomic characteristics of Xp11.2 translocation renal cell carcinoma (Xp11.2 RCC) in adults, we analyzed 9 Xp11.2 RCCs, confirmed by transcription factor E3 (TFE3) immunohistochemistry, in patients aged ?20 years. TFE3 expression was also determined in 12 cases of alveolar soft part sarcoma (ASPS) served as a positive control. Comparative genomic hybridization (CGH) was used to investigate genomic imbalances in all Xp11.2 RCC cases. Most of our Xp11.2 RCC patients (5/9) presented with TNM stages 3-4, and 6 patients died 10 months to 7 years after their operation. Histologically, Xp11.2 RCC was composed of a mixed papillary nested/alveolar growth pattern (8/9). Immunostaining showed that all Xp11.2 RCC and ASPS cases had strong TFE3 expression and high positive ratios for p53 and vimentin. However, there were significant differences in the expression of AMACR (p<0.001), AE1/AE3 (p=0.002), and CD10 (p=0.024) between the 2 diseases. CGH profiles showed chromosomal imbalances in all 9 Xp11.2 RCC cases; gains were observed in chromosomes Xp11 (6/9), 7q20-25, 12q25-31 (5/9), 7p16-24 (4/9), 8p12-13, 8q20-21, 16q20-22, 17q25-26, 20q22-23 (4/9), and losses occurred frequently on chromosomes 3p12-16, 9q31-32, 14q22-24 (4/9). Our Conclusions show Xp11.2 RCC that occur in adults may be aggressive cancers, the expressions of AMACR, CD10, AE1/AE3 are helpful in the differential diagnosis between Xp11.2 RCC and ASPS, and CGH assay is a useful complementary method for confirming the diagnosis of Xp11.2 RCC.
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Arginine-stabilized mPEG-PDLLA (50/50) polymeric micelles of docetaxel by electrostatic mechanism for tumor-targeted delivery.
Drug Deliv
PUBLISHED: 11-13-2013
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Abstract Arginine-stabilized, docetaxel-loaded polymeric micelles (AR-DTX-PM) were prepared to enhance the physical stability of micelles and control the degradation of docetaxel (DTX). Amphiphilic diblock copolymers, methoxy-(Polyethylene Glycol)-block-Poly (D, L-lactide) (mPEG-PDLLA) were synthesized and used for the formulation of lyophilized DTX-PM powders. The micelles were found to have diameters of 20-30?nm with narrow polydispersity, and the entrapment efficiency was 90-100%. The accumulative release of AR-DTX-PM was higher than that of glucose-dispersed DTX-PM (Glu-DTX-PM). The results of both physical and chemical stability studies showed that the concentration of arginine required for optimum stability was 2.0?mg/ml. Preliminary investigation of the mechanisms of stabilization by arginine suggested that it is due to the electrostatic interaction as well as hydrogen bonds between DTX and arginine. The acute toxicity studies demonstrated that AR-DTX-PM was better tolerated in beagle dogs than DTX injection. However, the pharmacokinetic studies revealed no significant difference in Cmax and AUC of AR-DTX-PM compared to DTX injection. When AR-DTX-PM was administrated at a dose of 30?mg/kg, the antitumor effect was stronger than that of commercial DTX injection at 10?mg/kg, and the increase of administration dose did not cause higher toxicity. The in vivo imaging test showed that the residence time of AR-DTX-PM at tumor sites was longer than its commercial formulation. In a word, it is expected that AR-DTX-PM can reduce systemic toxicity while retaining antitumor efficacy in cancer patients.
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In vitro toxicity of different-sized ZnO nanoparticles in Caco-2 cells.
Nanoscale Res Lett
PUBLISHED: 10-29-2013
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There has been rapid growth in nanotechnology in both the public and private sectors worldwide, but concern about nanosafety exists. To assess size-dependent cytotoxicity on human cancer cells, we studied the cytotoxic effect of three kinds of zinc oxide nanoparticles (ZnO NPs) on human epithelial colorectal adenocarcinoma (Caco-2) cells. Nanoparticles were first characterized by size, distribution, and intensity. Multiple assays have been adopted to measure the cell activity and oxidative stress. The cytotoxicity of ZnO NPs was time dependent and dose dependent. The 24-h exposure was chosen to confirm the viability and accessibility of the cells and taken as the appropriate time for the following test system. The IC50 value was found at a low concentration. The oxidative stress elicited a significant reduction in glutathione with increase in reactive oxygen species and lactate dehydrogenase. The toxicity resulted in a deletion of cells in the G1 phase and an accumulation of cells in the S and G2/M phases. One type of metallic oxide (ZnO) exerted different cytotoxic effects according to different particle sizes. Data from the previous experiments showed that 26-nm ZnO NPs appeared to have the highest toxicity to Caco-2 cells. The study demonstrated the toxicity of ZnO NPs to Caco-2 cells and the impact of particle size, which could be useful in the medical applications.
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[Studies on fluorescence spectral characteristics of fulvic acid (FA) from Xingkai Lake sediments].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 09-25-2013
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Four samples (sample No. HXXD, HXXX, HXDX and HXDB) were taken from Xingkai Lake Sediments in Heilongjiang province and fluorescence spectral characteristics of Fulvic acid (FA) from sediments were studied. Conventional and excitation-emission matrix (EEM) all indicated that FA from HXXD sediment exhibited primary peaks at longer wavelengths. The analysis of fluorescence characteristic parameters indicated that the degree of humification of FA from all sample points were in the order: HXXD > HXDX > HXDB > HXXX. Fluorescence index (f450/500) suggested that FA from HXXD mainly originated from terrestrial sources, while the FA from other samples mainly originated from aquatic organism sources and terrestrial sources. Based on EEM fluorescence regional integration (FIR), the percent fluorescence responses (P(i, n)) of five regions in 3EEMs was calculated. The distributions of P(V, n) (humic acid-like region) and P(III, n) (fulvic acid-like region) were the largest in all samples. The conclusion of the degree of humification of FA based on FIR was consistent with the analysis of conventional fluorescence parameters. The correlation analysis showed that, gamma(A, C) was significantly correlative with P(V, n)/P(III, n), (P(V, n) + P(III, n))/(P(I, n) + P(II, n) + P(III, n)) and P(V, n). The results suggest that gamma(A, C) index is a reasonable tool for assessing humification degree of FA from Xingkai Lake sediments.
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Ambient arylmagnesiation of alkynes catalysed by ligandless nickel(ii).
Chem. Commun. (Camb.)
PUBLISHED: 09-18-2013
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A simple and efficient catalytic arylmagnesiation of diarylacetylenes and aryl(alkyl)acetylenes is accomplished by NiCl2·6H2O at r.t. in the absence of stabilising ligands. The corresponding tetra-substituted alkenes can be obtained in good yields by subsequent treatment with different electrophiles.
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The potential value of the neutral comet assay and ?H2AX foci assay in assessing the radiosensitivity of carbon beam in human tumor cell lines.
Radiol Oncol
PUBLISHED: 09-01-2013
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Carbon ions ((12)C(6+)) are high linear energy transfer (LET) radiation characterized by higher relative biological effectiveness than low LET radiation. The assessment of tumour radiosensitivity would be particularly useful in optimizing the radiation dose during radiotherapy. The aim of the current study was to evaluate the potential value of the neutral comet assay and ?H2AX foci assay in assessing (12)C(6+) radiosensitivity of tumour cells.
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[Odontogenic differentiation of bone marrow-derived mesenchymal stem cells induced by periodontal ligament stem cells].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 08-17-2013
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To investigate the mechanism underlying the mechanism of odontogenic differentiation of bone marrow-derived mesenchymal stem cells (BMMSCs) induced by periodontal ligament stem cells (PDLSCs), and offer an experimental evidence for the combination of the two types of stem cells to make regenerative periodontal complex.
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Level alignment of a prototypical photocatalytic system: methanol on TiO2(110).
J. Am. Chem. Soc.
PUBLISHED: 07-26-2013
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Photocatalytic activity depends on the optimal alignment of electronic levels at the molecule-semiconductor interface. Establishing the level alignment experimentally is complicated by the uncertain chemical identity of the surface species. We address the assignment of the occupied and empty electronic levels for the prototypical photocatalytic system consisting of methanol on a rutile TiO2(110) surface. Using many-body quasiparticle (QP) techniques, we show that the frontier levels measured in UV photoelectron and two-photon photoemission spectroscopy experiments can be assigned to molecularly chemisorbed methanol rather than its dissociated product, the methoxy species. We find that the highest occupied molecular orbital of the methoxy species is much closer to the valence band maximum, suggesting why it is more photocatalytically active than the methanol molecule. We develop a general semiquantitative model for predicting many-body QP energies based on the electronic screening within the bulk, molecular, or vacuum regions of the wave functions at molecule-semiconductor interfaces.
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High-throughput profiling of alpha interferon- and interleukin-28B-regulated microRNAs and identification of let-7s with anti-hepatitis C virus activity by targeting IGF2BP1.
J. Virol.
PUBLISHED: 07-03-2013
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Hepatitis C virus (HCV) infection is a major cause of severe liver disease. Interferon (IFN)/ribavirin treatment remains the standard therapeutic regimen for HCV infection in most countries. IFN-stimulated genes are believed to contribute to antiviral effects. However, emerging evidence suggests that microRNAs (miRNAs), a class of noncoding small RNAs, are involved in the control of viral infection. Here, we systematically profiled the hepatocyte expression of a set of 750 miRNAs in response to alpha interferon (IFN-?) and interleukin-28B (IL-28B) treatments. The anti-HCV activity of differentially expressed miRNAs was evaluated using cell culture-derived HCV in vitro. The results demonstrate that let-7b had a significant anti-HCV effect by inhibiting HCV replication and viral protein translation in human hepatoma cells. In particular, we show that the inhibition of let-7b attenuated the anti-HCV effects of IFN-? and IL-28B. Furthermore, we show that the host factor insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) is a target of let-7b. IGF2BP1 was required for HCV replication, and its expression was downregulated by IFN-? and IL-28B. Deletion of the wild-type seed region of let-7b abolished its antiviral activity. Finally, we demonstrate that other let-7 family miRNAs were able to inhibit HCV and to suppress IGF2BP1 expression. In conclusion, we provide an example of a host miRNA regulated by type I and type III IFNs that inhibits HCV replication and infectivity by targeting host targets. These results highlight the important role of miRNAs in the host antiviral immune response and provide a novel candidate for anti-HCV therapy.
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Association of endothelin-converting enzyme-1b C-338A polymorphism with increased risk of ischemic stroke in Chinese Han population.
J. Mol. Neurosci.
PUBLISHED: 07-02-2013
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Endothelin-converting enzyme-1b (ECE-1b) C-338A is a polymorphism located in ECE-1 gene promoter, which has been reported to correlate with the risk of carotid atherosclerosis. We conducted a hospital-based case-control study of 309 patients with ischemic stroke and 309 controls matched on age and gender. The frequencies of ECE-1b-338 CC, CA, and AA genotypes in cases (45.0, 40.4, and 14.6 %) were significantly different from those of controls (53.1, 39.1, and 7.8 %, ?(2) = 8.519, P = 0.014), respectively. Compared with C carriers, A alleles showed correlation with a 42 % increased risk of ischemic stroke (adjusted odds ratio (OR) = 1.42, 95 % CI = 1.11-1.81). After adjustment for potential risk factors, the AA genotype still kept positive correlation with ischemic stroke (OR = 1.78; 95 % CI = 1.06-3.54). In stratified analyses, the significant association of the A allele with ischemic stroke was observed in female subjects (adjusted OR = 1.64, 95 % CI = 1.17-2.89) and the subjects with age ? 64 years old (adjusted OR = 2.09, 95 % CI = 1.38-3.23). The present study suggested that the C-338A polymorphism of the ECE-1b gene was associated with an increased risk of ischemic stroke in the Chinese Han population.
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Overexpression of HLA-G Is positively associated with Kazakh esophageal squamous cell carcinoma in Xinjiang, China.
Viral Immunol.
PUBLISHED: 06-19-2013
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HLA-G is a class I HLA that has gained much attention due to its multiple functions in the immune system. More important, some studies found HLA-G may be detrimental in tumors and viral infections, and the detection of HLA-G expression might serve as a clinical marker in the prediction of clinical outcomes for certain types of carcinoma. We assessed the association between the development of Kazakh esophageal squamous cell carcinoma (ESCC) harboring high-risk HPV infection and the expression of HLA-G. The expression of HLA-G was detected by S-P immunohistochemical staining in 60 cases of Kazakh ESCC tissues and 40 cases of Kazakh tumor adjacent normal tissues. HPV16 infection in ESCC was detected by genotype-specific polymerase chain reaction. HPV16 infection rate in Kazakh ESCC was 35.0%, significantly higher than that of the infection rate of the adjacent normal tissues 15% (p<0.05, OR=3.051; 95% CI: 1.103-8.438). The expression of HLA-G in Kazakh ESCC was 75.0% (45/60), significantly higher than that of tumor adjacent normal tissues (17.5%; p<0.05); expression of HLA-G was slightly higher in HPV16-positive than HPV16-negative ESCC, but the difference was not statistically significant (p>0.05). The positive expression rate of HLA-G was closely related to depth of invasion and clinical stage (p<0.05 for all), but was not related to age, sex, tumor location, histologic grade, and nodal status (p>0.05 for all). Overexpression of HLA-G was a characteristic feature of Kazakh ESCC; HLA-G may be involved in Kazakh ESCC carcinogenesis and HPV infection.
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Trans [O=Re(V)-OH] core stabilised by chelating N-heterocyclic dicarbene ligands.
Dalton Trans
PUBLISHED: 06-05-2013
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Three Re(v) N-heterocyclic carbene complexes [ReO(OH)(L(Me))(2)][PF(6)](1.4)[ReO(4)](0.6), [ReO(OH)(L(iPr))(2)][PF(6)](1.4)[ReO(4)](0.6) and [ReO(OH)(L(Bn))(2)][PF(6)](1.3)[ReO(4)](0.7) (L(Me) = 1,1-methylene-bis(3-methylimidazole-2-ylidene); L(iPr) = 1,1-methylene-bis(3-isopropylimidazole-2-ylidene) and L(Bn) = 1,1-methylene-bis(3-benzylimidazole-2-ylidene)) with trans oxo and hydroxo at axial positions have been synthesized.
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[Discussion on hyperspectral index for the estimation of cotton canopy water content].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 05-24-2013
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Proper vegetation indices have decisive influences on the precision of hyperspectral estimation models for surface parameters. In the present paper, in order to find the proper hyperspectral indices for cotton canopy water content estimation, two water parameters for cotton canopy water content (EWT(canopy), equivalent water thickness; VWC, vegetation water content) and corresponding hyperspectra data were analyzed. A rigorous search procedure was used to determine the best index predictors of cotton canopy water. In the procedure, all possible ratio indices and normalized difference indices were derived from the canopy hyperspectra, involving all the two-band combinations between 350 nm and 2500 nm. Then the correlation between two water parameters and all combination indices were analyzed, and the best indices which produced maximum correlation coefficients were determined. Finally, the indices were compared with the published water indices for their performances in estimation of cotton canopy water content. The results showed that for the estimation of EWT(canopy), the new developed ratio index R1 475/R1 424 and normalized difference index (R1 475 -R1 424)/(R1 475 + R1 424) was the most proper one, and the correlation coefficient of the estimated and measured EWT(canopy) reached 0.849. For the estimation of VWC, the performance of published index was better than new developed index, the best suitable water indices for VWC estimation were (R835 - R1 650)/(R835 + R1 650), and the correlation coefficient of the estimated and measured VWC was 0.849.
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The depolymerized fucosylated chondroitin sulfate from sea cucumber potently inhibits HIV replication via interfering with virus entry.
Carbohydr. Res.
PUBLISHED: 05-22-2013
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Fucosylated chondroitin sulfate (FuCS-1) is a nontoxic and water-soluble depolymerized glycosaminoglycan obtained from the sea cucumber Thelenota ananas. Anti-HIV activities of FuCS-1 were evaluated in the present study. FuCS-1 was effective in blocking laboratory strain HIV-1IIIB entry and replication (4.26?g/mL and 0.73?g/mL, respectively), and inhibiting infection by clinic isolate HIV-1KM018 and HIV-1TC-2 (23.75?g/mL and 31.86?g/mL, respectively) as well as suppressing HIV-1 drug-resistant virus. It also inhibited HIV-2ROD and HIV-2CBL-20 replication (100?g/mL). Notably, FuCS-1 showed highly effective antiviral activity against T-20-resistant strains (EC50 values ranging from 0.76?g/mL to 1.13?g/mL). Further studies indicated that FuCS-1 can potently bind the recombinant HIV-1 gp120 protein, but no inhibition of recombinant HIV-1 reverse transcriptase was observed. In conclusion, FuCS-1 inhibited several strains of HIV-1 replication with different potencies. These results suggest that FuCS-1 may possess great potential to be further developed as novel HIV-1 entry inhibitor for treatment of HIV/AIDS patients, particularly for those infected by T-20-resistant variants.
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HIV Infection and Sexual Behaviors Among Non-Commercial Men Who Have Sex with Men at Different Venues.
Arch Sex Behav
PUBLISHED: 05-12-2013
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The prevalence of HIV infection among men who have sex with men (MSM) has increased rapidly in China. Previous studies suggested that some venue-specific characteristics could significantly affect MSMs sexual behaviors that were related to HIV transmission. Thus, to compare the HIV infection rates and related risky sexual behaviors among MSM at different venues, we conducted a cross-sectional study with time-location sampling in Shenzhen, China. Among the 801 MSM recruited in the study, 7.0 % (n = 56) were found to be HIV positive, with 0.9 % of MSM at bars (BMSM), 3.5 % of MSM at suburban recreational centers (RMSM), 8.1 % of MSM at saunas (SMSM), 9.3 % of MSM at parks (PMSM), and 10.1 % of MSM at dorm-based venues (DMSM). HIV infection was significantly more prevalent in MSM in dorm-based venues, parks, and saunas than in other venues. Compared to MSM in other venues, BMSM were more likely to be single, drug and alcohol users, but less likely to be HIV and syphilis positive. More PMSM reported having unprotected anal intercourse with other men while more SMSM reported having multiple male sex partners and more RMSM had a low level of HIV-related knowledge. The results indicated that MSM frequenting different venues were inconsistent with regards to demographic characteristics, HIV and syphilis infection rates, and risky sexual behaviors. Greater efforts are needed to develop intervention strategies that target specific venues and risky behaviors.
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Antitumor effects and preliminary systemic toxicity of ANISpm in vivo and in vitro.
Anticancer Drugs
PUBLISHED: 05-10-2013
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Polyamines as a vector to ferry toxic agents have attracted attention, and naphthalimide-polyamine conjugates show potent activity and tumor cell selectivity. The present study was carried out to evaluate the antitumor effects and preliminary systemic toxicity of ANISpm, a novel 3-amino-naphthalimide-spermine conjugate. The polyamine transport system recognition of ANISpm, supported by ?-difluoromethylornithine (DFMO)/spermidine (Spd) experiments, is in accordance with its potent cell selectivity between human hepatoma HepG2 cells and normal QSG7701 hepatocyte. The antiproliferative effect is because of ANISpm-induced cell apoptosis, a common characteristic of both naphthalimide and polyamine analogs. Various apoptotic assessment assays have shown that ANISpm can induce apoptosis through the PI3K/Akt signal pathway. The apoptotic signaling cascade involves Akt inactivation, which results in a series of cellular events. The downstream pathway includes Bad dephosphorylation, dissociation of 14-3-3 and Bad, and binding to Bcl-xL, which triggers the disruption of the mitochondrial membrane, release of cytochrome c, and caspases cascade activation. Furthermore, the Akt/mTOR signal pathway is also involved in ANISpm-mediated cell-cycle arrest. Additive DFMO or Spd, which only enhances or attenuates ANISpm-mediated cell apoptosis, respectively, does not alter the signal pathway. In addition, preliminary toxicology evaluation showed that ANISpm had no obvious system toxicity at a dose of 2.5 mg/kg, which exerted potent antitumor activity in vivo, especially hematotoxicity. Thus, ANISpm merits further investigation as a potential chemotherapeutic agent against hepatocellular carcinoma.
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Hierarchical organization of spherical assembly with reversibly photocontrollable cross-links.
J. Org. Chem.
PUBLISHED: 05-08-2013
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A ternary photocontrollable assembly was hierarchically constructed by the "orthogonal" host-guest interaction of different types of cyclodextrins toward the porphyrin and azobenzene. Spectroscopic titrations and microscopic investigations demonstrate that the inclusion complex of azobenzene modified water-soluble porphyrin (1) with phthalocyanine-grafted permethyl ?-cyclodextrins (2) could be reversibly cross-linked to relatively larger nanospheres with naphthyl bridged bis(?-cyclodextrin)s (3). Moreover, the large-sized spheres (1·2·3) could be disassembled and switched to small-sized complex (1·2) upon the photoinduced isomerization of an azophenyl group.
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Performance of a multilayered small-diameter vascular scaffold dual-loaded with VEGF and PDGF.
Biomaterials
PUBLISHED: 04-14-2013
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The urgent needs of functional arterial replacements for curing the vascular system diseases have been proposed for many years. However, an ideal small-diameter vascular scaffold, which is nonthrombogenic, minimizes intimal hyperplasia, matches the mechanical properties of natural vessels, and supports neovascular tissue reconstruction, is still in progress. For this purpose, we previously attempted dual-delivery of VEGF and PDGF by double-layered electrospun membranes. Here, a multilayered vascular scaffold in 1.5-mm diameter with sufficient mechanical properties was developed by electrospinning from poly(ethylene glycol)-b-poly(L-lactide-co-?-caprolactone) (PELCL), poly(L-lactide-co-glycolide) (PLGA), poly(?-caprolactone) (PCL) and gelatin. Spatio-temporal releases of vascular endothelial growth factor (VEGF) and platelet-derived growth factor-bb (PDGF) were specially controlled by the inner PELCL and middle PLGA layers, respectively, and the outer PCL layer contributed to the mechanical stability. Introduction of gelatin improved vascular endothelial cells adhesion at first, and loosen membrane after its degradation facilitated vascular smooth muscle cells (VSMCs) ingrowth. Cell activities indicated dual release of growth factors promoted endothelialization and inhibited VSMCs hyperproliferation. The small-diameter vascular scaffold dual-loading VEGF and PDGF could maintain patency in rabbit left common carotid artery for 8 weeks. It is concluded that the specially prepared fibrous scaffold in multilayer could benefit blood vessel reconstruction.
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Expression of neuropeptide Y and pro-opiomelanocortin in hypothalamic arcuate nucleus in 17?-ethinyl estradiol-induced intrahepatic cholestasis pregnant rat offspring.
J. Obstet. Gynaecol. Res.
PUBLISHED: 04-02-2013
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The purpose of this study was to investigate the expression of neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) in the hypothalamic arcuate nucleus of intrahepatic cholestasis pregnant (ICP) offspring.
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The tree shrew provides a useful alternative model for the study of influenza H1N1 virus.
Virol. J.
PUBLISHED: 04-02-2013
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The influenza pandemics have resulted in significant morbidity and mortality worldwide. Animal models are useful in the study of influenza virus pathogenesis. Because of various limitations in current laboratory animal models, it is essential to develop new alternative animal models for influenza virus research aimed at understanding the viral and host factors that contribute to virus infection in human.
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A novel protein from Eupolyphaga sinensis inhibits adhesion, migration, and invasion of human lung cancer A549 cells.
Biochem. Cell Biol.
PUBLISHED: 03-28-2013
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Eupolyphaga sinensis Walker is an important insect used in Chinese traditional medicine. In this study, we purified a 72-kDa anticancer protein, designated as EPS72, from this species using ammonium sulfate precipitation, ultrafiltration, CM Sepharose Fast Flow cation exchange, Q Sepharose High Performance (HP) anion exchange, Butyl Sepharose HP hydrophobic chromatography, and Superdex 75 gel filtration chromatographic techniques. EPS72 exhibited a potent anticancer activity against the human lung cancer A549 cell line (IC50, 18.76 ?g/mL). Further study showed that EPS72 could induce A549 cell detachment and apoptosis, inhibit cell adhesion to fibronectin and collagen IV, and restrain cell migration and invasion. Moreover, EPS72 significantly decreased the expression of ?1-integrin. This study suggests that EPS72 could potentially be developed as a novel anticancer therapeutic agent due to its possible antimetastatic activity.
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Inducing effect on the percolation transition in complex networks.
Nat Commun
PUBLISHED: 03-27-2013
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Percolation theory concerns the emergence of connected clusters that percolate through a networked system. Previous studies ignored the effect that a node outside the percolating cluster may actively induce its inside neighbours to exit the percolating cluster. Here we study this inducing effect on the classical site percolation and K-core percolation, showing that the inducing effect always causes a discontinuous percolation transition. We precisely predict the percolation threshold and core size for uncorrelated random networks with arbitrary degree distributions. For low-dimensional lattices the percolation threshold fluctuates considerably over realizations, yet we can still predict the core size once the percolation occurs. The core sizes of real-world networks can also be well predicted using degree distribution as the only input. Our work therefore provides a theoretical framework for quantitatively understanding discontinuous breakdown phenomena in various complex systems.
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Sodium cubane and double-cubane aggregates of hybridised salicylaldimines and their transmetallation to nickel for catalytic ethylene oligomerisation.
Chem. Commun. (Camb.)
PUBLISHED: 03-27-2013
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Deprotonation of functional salicylaldimines with NaH invariably results in cubane or double-cubane Na(I) aggregates which transmetallate with Ni(II) under different stoichiometric conditions to give Ni(II) complexes that are catalytically active towards ethylene oligomerisation.
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Semihydrogenated BN sheet: a promising visible-light driven photocatalyst for water splitting.
Sci Rep
PUBLISHED: 03-12-2013
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Based on first principles calculations, we predict semihydrogenated graphitic BN (sh-BN) sheet is a potential metal-free visible-light driven photocatalyst for water splitting. The ground state of sh-BN is a strip-like antiferromagnetic semiconductor with a band gap suitable for visible-light absorption. The redox potentials of water splitting are all located inside the band gap and the probability densities of valence and conduction bands are distributed apart spatially leading to a well-separation of photogenerated electrons and holes.
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Phase behavior of concentrated hydroxypropyl methylcellulose solution in the presence of mono and divalent salt.
Carbohydr Polym
PUBLISHED: 03-05-2013
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Thermo reversible sol-gel transitions of hydroxypropylmethylcellulose (HPMC) are critical for many pharmaceutical, cosmetic, and food applications. This study examined the effects of salt (NaCl and CaCl2) on the viscoelastic properties of concentrated low molecular weight HPMC solutions and found that the gelation temperature decreased linearly as a function of salt concentrations, independent of valency of cations and the mole concentration of anions. Thermal analysis showed that the depression of melting temperature can be fitted for both NaCl and CaCl2 as a function of the total number of ions by a single linear curve, which was consistent with the melting point depression of pure water by NaCl and CaCl2, but with a higher linear slope.
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A multiplex RT-PCR assay for rapid and differential diagnosis of four porcine diarrhea associated viruses in field samples from pig farms in East China from 2010 to 2012.
J. Virol. Methods
PUBLISHED: 02-28-2013
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Since October 2010, clinical outbreaks of diarrhea in suckling piglets have reemerged in pig-producing areas of China, causing an acute increase in the morbidity and mortality in young piglets. Four viruses, porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine group A rotaviruses (GAR), and porcine circovirus 2 (PCV2), are the major causative agents of enteric disease in piglets. A novel multiplex reverse transcription-polymerase chain reaction (mRT-PCR) was developed for simultaneous detection of the four viruses in field samples from piglets. A mixture of four previously published pairs of primers were used for amplification of viral gene, yielding four different amplicons with sizes of 481 bp for PCV2, 651 bp for PEDV, 859 bp for TGEV, and 309 bp for GAR, respectively. The sensitivity of the mRT-PCR using plasmids containing the specific viral target fragments was 2.17 × 10(3), 2.1 × 10(3), 1.74 × 10(4) and 1.26 × 10(4)copies for the four viruses, respectively. A total of 378 field samples were collected from suckling piglets with diarrhea in East China from October 2010 to December 2012, and detected by mRT-PCR. The PEDV-positive rates of the three years were 69.2%, 62.8% and 54.9%, respectively, suggesting that PEDV was a major pathogen in these diarrheal outbreaks. Taken together, all data indicated that this mRT-PCR assay was a simple, rapid, sensitive, and cost-effective detection method for clinical diagnosis of mixed infections of porcine diarrhea associated viruses.
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Role of point defects on the reactivity of reconstructed anatase titanium dioxide (001) surface.
Nat Commun
PUBLISHED: 02-22-2013
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The chemical reactivity of different surfaces of titanium dioxide (TiO2) has been the subject of extensive studies in recent decades. The anatase TiO2(001) and its (1 × 4) reconstructed surfaces were theoretically considered to be the most reactive and have been heavily pursued by synthetic chemists. However, the lack of direct experimental verification or determination of the active sites on these surfaces has caused controversy and debate. Here we report a systematic study on an anatase TiO2(001)-(1 × 4) surface by means of microscopic and spectroscopic techniques in combination with first-principles calculations. Two types of intrinsic point defects are identified, among which only the Ti(3+) defect site on the reduced surface demonstrates considerable chemical activity. The perfect surface itself can be fully oxidized, but shows no obvious activity. Our findings suggest that the reactivity of the anatase TiO2(001) surface should depend on its reduction status, similar to that of rutile TiO2 surfaces.
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Rapidly in situ forming chitosan/?-polylysine hydrogels for adhesive sealants and hemostatic materials.
Carbohydr Polym
PUBLISHED: 02-15-2013
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A novel in situ forming polysaccharides/polypeptide hydrogel composed of naturally derived materials for applications as adhesive sealant and hemostatic material was developed via Michael addition crosslinking, taking advantage of its mild condition. Thiol-modified chitosan (CSS) was fast in situ crosslinked by an efficient polypeptide crosslinker (EPLM) which was prepared by introducing maleimide groups onto ?-polylysine. Gelation can happen swiftly within 15-215s depending on the CSS concentration, the degree of substitution (DS) of maleimide groups, and the molar ratio of maleimide group to thiol group. Results indicated that storage modulus of the hydrogel increased dramatically with the increase of CSS concentration and DS of maleimide. The obtained adhesive hydrogel had an adhesion strength 4 times higher than that of the commercial fibrin glue. Notably, it is non-toxic to L929 cells and exhibits excellent prompt hemostatic property. Polysaccharides/polypeptide structure designed here facilitates to improve both the biocompatibility and the adhesive property.
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Self-sorting of four organic molecules into a heterowheel polypseudorotaxane.
Chemistry
PUBLISHED: 02-15-2013
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The social self-sorting supramolecular assembly is described by non-covalent interactions among four organic components. Toward this goal, a series of self-sorting systems have been investigated by mixing two or three different compounds; naphthyl-bridged bis(?-cyclodextrin), N,N-dioctyl-4,4-bipyridinium, 2,6-dihydroxynaphthalene, and cucurbit[8]uril. The influence of alkyl chains of viologen derivatives and the binding abilities of these systems have also been studied. Their integrative self-sorting led to the exclusive formation of the purple supramolecular heterowheel polypseudorotaxane. The heterowheel polypseudorotaxane is a thermodynamically stable self-sorted product, and consists of two different macrocycles with three sorts of different non-covalent interactions. Its structure was established by NMR spectroscopy and UV/Vis absorption spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM), dynamic light-scattering (DLS), diffusion-ordered spectroscopy (DOSY), and viscosity measurements.
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Cross-coupling of alkyl halides with aryl or alkyl Grignards catalyzed by dinuclear Ni(II) complexes containing functionalized tripodal amine-pyrazolyl ligands.
Dalton Trans
PUBLISHED: 02-14-2013
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Structurally distinctive dinuclear Ni(II) complexes with furan or thiophene tethered amine-pyrazolyl tripodal hybrid ligands have been synthesized and crystallographically characterized. All complexes are catalytically active towards cross-coupling of aryl/alkyl Grignard reagents with ?-H containing alkyl halides at room temperature in the presence of N,N,N,N-tetramethylethylenediamine (TMEDA). The catalytic efficacy of the complexes is dependent on the tether substituent at the central amine. Two species, Ni(II) TMEDA and Mg(II) TMEDA complexes, have been isolated from the catalytic reaction mixtures under different conditions. Some ligand-stabilized Ni(II) and Mg(II) bimetallic species have also been identified in the ESI-MS spectra.
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Antiviral activity of Isatis indigotica root-derived clemastanin B against human and avian influenza A and B viruses in vitro.
Int. J. Mol. Med.
PUBLISHED: 02-07-2013
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Clemastanin B, 7S,8R,8R-(-)-lariciresinol-4,4-bis-O-?-D-glucopyranoside, is one of the major lignans extracted from Isatis indigotica root (IIR). In this study, the anti-influenza activities of clemastanin B were evaluated in vitro. Clemastanin B was found to inhibit different subtypes of human (H1N1, including swine-origin H1N1; H3N2 and influenza B) and avian influenza viruses (H6N2, H7N3, H9N2) at different magnitudes of activity (IC50 0.087-0.72 mg/ml) while this compound was inactive against respiratory syncytial virus (RSV), adenovirus 3 (ADV3), parainfluenza virus 3 (PIV3), enterovirus 71 (EV71) and human rhinovirus (HRV). An apparent virus titer reduction was detected when MDCK cells were treated with clemastanin B after viral infection, particularly at the early stage, and the ribonucleoprotein (RNP) of the influenza virus was retained in the nucleus after treatment with clemastanin B. These results demonstrated that clemastanin B targets viral endocytosis, uncoating or RNP export from the nucleus. Furthermore, treatment with clemastanin B did not easily result in the emergence of viral drug resistance. The effects of clemastanin B demonstrated in this study may promote the antiviral study of IIR, but additional studies are required to define the anti-influenza mechanism(s).
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Irbesartan-mediated AT1 receptor blockade attenuates hyposmotic-induced enhancement of IKs current and prevents shortening of action potential duration in atrial myocytes.
J Renin Angiotensin Aldosterone Syst
PUBLISHED: 02-07-2013
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INTRODUCTION: Stretch of the atrial membrane upregulates the slow component of delayed rectifier K(+) current (I(Ks)). Blockade of angiotensin II subtype 1 receptors (AT(1)R) attenuates this increase in I(Ks). The present study aimed to examine the effects of irbesartan, a selective AT(1)R blocker (ABR), on both the enhancement of I(Ks) and the shortening of action potential duration (APD) induced by stretching atrial myocytes for exploring the mechanisms underlying the prevention of atrial fibrillation (AF) by ABR. METHODS: Hyposmotic solution (Hypo-S) was used to stretch guinea pig atrial myocytes. I(Ks) and APD were recorded using the whole-cell patch-clamp technique. RESULTS: Irbesartan (1-50 ?M) attenuated the Hypo-S-induced increase in I(Ks) and shortening of APD(90). Hypo-S increased the I(Ks) by 113.4%, whereas Hypo-S + 1 ?M irbesartan and Hypo-S + 50 ?M irbesartan increased the I(Ks) by only 74.5% and 70.3%, respectively. In addition, Hypo-S shortened the APD(90) by 19.0%, whereas Hypo-S + 1 ?M irbesartan and Hypo-S + 50 ?M irbesartan shortened the APD(90) by 12.1% and 12.0%, respectively. CONCLUSION: The actions of irbesartan on electrical changes induced by stretching atrial myocytes are associated with blocking AT(1)R. These actions may be beneficial for treating AF.
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Effects of tea polyphenols on the post-mortem integrity of large yellow croaker (Pseudosciaena crocea) fillet proteins.
Food Chem
PUBLISHED: 02-05-2013
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Tea polyphenols (TP) are known to be important for the post-mortem deterioration of fish muscle and can enhance food quality. To shed light on the influence of TP on the status of large yellow croaker muscle proteins, control and treated fillets (0.1% TP, 0.2% TP and 0.3% TP, w/v) were analysed periodically for myofibrillar protein functional properties (Ca(2+)-ATPase activity, surface hydrophobicity, total sulfhydryl content, emulsion stability index and rheological behaviour). Degradation of the myofibrillar protein myosin could be clearly observed; several proteins were also observed to vary in abundance following post-mortem storage for 25 days. The present study offers new evidence that TP have an effective impact on muscle protein integrity post-mortem.
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Rapidly in situ forming adhesive hydrogel based on a PEG-maleimide modified polypeptide through Michael addition.
J Mater Sci Mater Med
PUBLISHED: 02-04-2013
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Polyethylene glycol-maleimide modified ?-polylysine (EPL-PEG-MAL) with a unique comb-shaped structure was designed and used as a novel crosslinker for thiolated chitosan (CSS). Novel polysaccharide/polypeptide bionic hydrogels based on CSS and EPL-PEG-MAL could form rapidly in situ within 1 min via Michael addition under physiological conditions. Rheological studies showed that introduction of PEG can dramatically improve the storage modulus (G) of the hydrogels and the optimal hydrogel system showed superior G of 1,614 Pa. The maximum adhesion strength reached 148 kPa, six times higher than that of fibrin glue. Cytotoxicity test indicated that the hydrogel is nontoxic toward growth of L929 cells. Gelation time, swelling ratio, storage modulus and adhesion strength of the hydrogels can be modulated by the content of PEG-maleimide, CSS concentration and molar ratio of maleimide group to thiol group. Benefiting from the fast gelation behaviors, desirable mechanical properties, relatively high adhesive performance and no cytotoxicity, these hydrogels have the potential applications as promising biomaterials for tissue adhesion and sealing.
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Giant photovoltaic effects driven by residual polar field within unit-cell-scale LaAlO? films on SrTiO?.
Sci Rep
PUBLISHED: 01-24-2013
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For polar/nonpolar heterostructures, Maxwells theory dictates that the electric potential in the polar components will increase divergently with the film thickness. For LaAlO?/SrTiO?, a conceptually intriguing route, termed charge reconstruction, has been proposed to avert such "polar catastrophe". The existence of a polar potential in LaAlO? is a prerequisite for the validity of the charge reconstruction picture, yet to date, its direct measurement remains a major challenge. Here we establish unambiguously the existence of the residual polar potential in ultrathin LaAlO? films on SrTiO?, using a novel photovoltaic device design as an effective probe. The measured lower bound of the residual polar potential is 1.0 V. Such a direct observation of the giant residual polar potential within the unit-cell-scale LaAlO? films amounts to a definitive experimental evidence for the charge reconstruction picture, and also points to new technological significance of oxide heterostructures in photovoltaic and sensing devices with atomic-scale control.
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Development of nanofibrous scaffolds for vascular tissue engineering.
Int. J. Biol. Macromol.
PUBLISHED: 01-24-2013
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Small-diameter vascular grafts can easily lead to thrombosis and intimal hyperplasia. So the rate of the long-term patency is not satisfactory. Scaffolds that can support the growth of cells and remain stable and passable in vivo are in great demand. Vascular scaffolds were fabricated by electrospinning RGD-recombinant spider silk protein (pNSR32), polycaprolactone (PCL) and chitosan (CS). In addition, the cytocompatibility, the stability and the patency of scaffolds in vivo were studied. The results demonstrated that Sprague-Dawley rat aortic endothelial cells (SDRAECs) could highly enhanced adhesion and proliferation, together with increasing stress of fiber formation, and intensive biological function (the expression of PECAM-1 and vWF, the secretion of NO), in the pNSR32/PCL/CS scaffolds, compared with in the pNSR32/PCL and PCL scaffolds. The cell cycle studies of SDRAECs also revealed that the scaffolds promoted the cells to enter the stage of divisional proliferation. Furthermore, pNSR32/PCL/CS scaffolds could support the growth of cells under physiologic conditions and are able to maintain the structural integrity and patency for at least 8 weeks in a SD rat abdominal aortic defect model.
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Synthesis, structure-activity relationship and biological activity of acridine derivatives as potent MDR-reversing agents.
Curr. Med. Chem.
PUBLISHED: 01-15-2013
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Multidrug resistance (MDR) mediated by P-glycoprotein is one of the best characterized transporter-mediated barriers to successful cancer chemotherapy. In an attempt to find MDR-reversing agents, a series of novel acridine derivatives were synthesized and evaluated for their in vitro antiproliferative activities against K562 and K562/ADM cells. Some of these compounds showed superior MDR-reversing activities than Amsacrine, the reference compound. Structure-activity relationships (SAR) of these compounds indicated that the N, N-diethylamine moiety had an affect on the in vitro antiproliferative activity. Interestingly, the compounds bearing N, N-diethylamine moiety showed higher growth-inhibitory activity against K562/ADM cells than K562 cells. The high duplex DNA binding affinity and inhibition of topoisomerase of these acridine compounds are maintained which were confirmed by fluorescent quenching and DNA topoisomerase II cleavage assay, respectively. Moreover, several compounds were examined for their ability to increase the accumulation of rhodamine 123 in K562 and K562/ADM cells, and the result suggested that they may be inhibitors for P-glycoprotein. Our study suggested that acridine framework is a potentially interesting scaffold for developing novel MDR-reversing agents.
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Cloning, characterization and expression of a cDNA encoding a granulin-like polypeptide in Ciona savignyi.
Biochimie
PUBLISHED: 01-14-2013
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Previous study in our laboratory confirmed that a novel polypeptide, CS5931 derived from Ciona savignyi possesses potent antitumor activity. In the present study, the full length cDNA of CS5931 precursor, termed Cs-pgrn-1 was cloned. The complete cDNA sequence of this gene consists of 685 bp containing an open reading frame (ORF) of 522 bp (173 amino acid residues). In silico analysis revealed that the polypeptide consists of two identical domains, similar with granulin (GRN) found in other species, and each of the domain encodes a polypeptide identical with CS5931. Phylogenetic analysis confirmed that CS5931 shares high homology with Ciona intestinalis GRN and is conserved during evolution. The polypeptide also shows high similarity with human GRN A, B, and C. Prediction of 3D protein structure revealed the 3D structure of CS5931 is very similar with human GRN A. The CS5931 was expressed using a prokaryotic expression system and the purified polypeptide inhibited the growth of several tumor cell lines in vitro via apoptotic pathway. Our study revealed that CS5931 has the potential to be developed as a novel antitumor agent.
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