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Find video protocols related to scientific articles indexed in Pubmed.
Modified retroperitoneoscopic port sites for surgery of upper urinary tract.
JSLS
PUBLISHED: 11-14-2014
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Our objective was to introduce our experience using modified retroperitoneoscopic port positions for operations of the upper urinary tract.
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Chemical constituents and bioactivities of Colla corii asini.
Drug Discov Ther
PUBLISHED: 11-11-2014
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In China, Colla corii asini is a health-care food and traditional Chinese medicine widely used in life-nourishing and clinical hematic antanemic therapy for more than 2,000 years. In this paper we compiled the chemical constituents isolated and detected from Colla corii asini including amino acids, proteins/gelatins, polysaccharides, volatile substances, inorganic substances, etc. Meanwhile we investigated the biological activities of Colla corii asini, which have been reported over the past few decades, including, hematologic diseases inhibitory activities, anti-aging activity, antitumor activity, immunomodulatory activity, bone repair activity, anti-inflammatory activity, antifatigue activity, etc. However, few reports on the relationships between the chemical constituents and bioactivities have been found, further studies of Colla corii asini are still necessary to facilitate research and development in the future.
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Staff nurse confidence in their skills and knowledge and barriers to caring for patients with ostomies.
J Wound Ostomy Continence Nurs
PUBLISHED: 11-08-2014
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Patients with ostomies often state that staff nurses display a lack of confidence in knowledge and skills related to ostomy care. This study examined the confidence and perceptions of barriers among hospital staff nurses when caring for ostomy patients.
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Templated deposition of multiscale periodic metallic nanodot arrays with sub-10 nm gaps on rigid and flexible substrates.
Nanotechnology
PUBLISHED: 10-30-2014
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Multiscale metallic nanostrucutures, which support hybrid coupling of plasmon resonances, are essential for the engineering of plasmonic devices. The fabrication of large area periodic multiscale structures still remains a challenge, considering the cost and efficiency. In this work, highly ordered multiscale Ag nanoarrays with lateral dimensions of up to 6 mm × 6 mm have been successfully fabricated on both rigid silicon and flexible polydimethylsiloxane (PDMS) substrate by thermal evaporation using ultrathin anodic aluminum oxide films as masks. Owing to the peculiarities of thermal evaporation and the variance of substrate surface energy, the unit cell of the periodic arrays consist of a core-satellite structure on silicon and randomly distributed child particles on PDMS, with gaps as small as 10 nm. The flexible Ag nanoarrays on PDMS demonstrate a broadband extraordinary optical transmission with an enhancement up to 2.7 times when normalized to the exposed area. Moreover, the transmission and diffraction properties can readily be controlled by stretching the PDMS. These tunable optical properties support the multiscale Ag nanoarrays to be applied in some optical and optoelectronic devices.
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[Prognostic value of decreased vasopressin modulation in the late-phase of septic shock patients].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 10-16-2014
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To investigate the prognostic value of decreased vasopressin (VP) modulation in the late-phase of septic shock.
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Controlling the localization of nanoparticles in assemblies of amphiphilic diblock copolymers.
Soft Matter
PUBLISHED: 10-14-2014
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We performed a dissipative particle dynamics (DPD) approach to study the self-assembly of AB diblock copolymer tethered nanoparticles (P) in dilute solutions. Different morphological aggregates, including spherical micelles, vesicles, disk-like micelles and rod-like micelles, were found by varying the interaction between block copolymers and nanoparticles. Most importantly, the nanoparticles can selectively localize in the different domains within the aggregates. When the repulsive interaction between block copolymers and nanoparticles aPA = aPB = 25, the nanoparticles are evenly distributed within the spherical micelles. While aPA or aPB increases, the nanoparticles gradually aggregate and separate from copolymers and then localize in the central portion of vesicular wall or disk-like and rod-like micelles. The degree of stretching of the tethered copolymer chains gradually grows with the increase of aPA or aPB, while the degree of stretching of solvophobic block B decreases when the morphologies change from spherical to disk-like micelles and further to rod-like micelles. This work illustrates that tuning the miscibility of copolymers and nanoparticles could be used to project the selective localization of nanoparticles within the aggregates self-assembled by diblock copolymer tethered nanoparticles in dilute solutions.
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Molecular Dynamics Investigation of the Adhesion Mechanism Acting between Dopamine and the Surface of Dopamine-Processed Aramid Fibers.
ACS Appl Mater Interfaces
PUBLISHED: 10-14-2014
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Dopamine, as a universal material for surface treatment, can effectively improve the surface performance of aramid fibers. However, directly processing the surface of aramid fibers using dopamine currently incurs a high cost. To seek dopamine substitutes, one must first explore the adhesion mechanism responsible for binding the dopamine to the surface of the fiber. In this study, we construct an all-atomic molecular dynamics model of an aramid fiber before and after surface modification using dopamine. A force field based on condensed-phase optimized molecular potentials for atomistic simulation studies (COMPASS) is used. Using it, we analyze the surface adhesion mechanism of polydopamines aggregated by 21 kinds of molecular structures typically found on the surface of aramid fibers. The results show that a clear and smooth interface is formed between the polydopamine nanofilm layer and the surface of the aramid fiber. The high atomic density of the polydopamine in the small interface region is found to be conducive to noncovalent bonds of polydopamines with the surface of the aramid fiber. In addition, we investigate the works of adhesion of the 21 molecular structures typically found on the surface of aramid fibers. The results suggest that the work of adhesion of 5,6-indolequinone is the highest, followed by annular eumelanin molecules with annular planar structure. Straight-chain shaped dimers proved to be the molecules with the highest adhesion ability of the dihydroxyindole chain oligomers. Therefore, there is reason to suppose that more molecular structures (as above) can be formed by processing the surface of aramid fibers using dopamine by controlling the processing conditions. These molecular structures help improve the adhesion ability of the dopamine on the surface of the aramid fiber. Additionally, if these polydopamine molecules with high adhesion ability can be synthesized on a large scale, then new surface-processing materials are possible.
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Photoelectric cooperative patterning of liquid permeation on the micro/nano hierarchically structured mesh film with low adhesion.
Nanoscale
PUBLISHED: 09-17-2014
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Stimuli-responsive surface wettability has been intensively studied, especially wettability controlled by photoelectric cooperation, which appears to be a trend for more effective surface wetting. In this field, the patterning of controllable surface wettability is still a challenge in the application of liquid-printing techniques because of the high adhesion and high responsive voltage, as well as low mechanical strength, of the substrate. Herein, we have demonstrated the patterning of liquid permeation controlled by photoelectric cooperative wetting on the micro/nano hierarchically structured ZnO mesh film. The special micro/nano hierarchically structured ZnO mesh is beneficial for lowering adhesion force on the mesh surface than those of the TiO2/AAO nanopore array films previously reported for the discontinuous tri-phase contact line, in addition to precisely controlled microscale liquid movement with considerably lower threshold voltage for the hierarchical structure. Moreover, the stainless-steel mesh with different pore sizes as a substrate behaves with higher mechanical strength and lower cost, compared with the anodized Ti mesh. Thus, this work is promising for accelerating the development of patterned liquid permeation and extending the application of micro/nanofluidic system and micronanoelectronic technology.
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Autophagy occurs within an hour of adenosine triphosphate treatment after nerve cell damage: the neuroprotective effects of adenosine triphosphate against apoptosis.
Neural Regen Res
PUBLISHED: 08-17-2014
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After hypoxia, ischemia, or inflammatory injuries to the central nervous system, the damaged cells release a large amount of adenosine triphosphate, which may cause secondary neuronal death. Autophagy is a form of cell death that also has neuroprotective effects. Cell Counting Kit assay, monodansylcadaverine staining, flow cytometry, western blotting, and real-time PCR were used to determine the effects of exogenous adenosine triphosphate treatment at different concentrations (2, 4, 6, 8, 10 mmol/L) over time (1, 2, 3, and 6 hours) on the apoptosis and autophagy of SH-SY5Y cells. High concentrations of extracellular adenosine triphosphate induced autophagy and apoptosis of SH-SY5Y cells. The enhanced autophagy first appeared, and peaked at 1 hour after treatment with adenosine triphosphate. Cell apoptosis peaked at 3 hours, and persisted through 6 hours. With prolonged exposure to the adenosine triphosphate treatment, the fraction of apoptotic cells increased. These data suggest that the SH-SY5Y neural cells initiated autophagy against apoptosis within an hour of adenosine triphosphate treatment to protect themselves against injury.
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Uncoupled surface spin induced exchange bias in ?-MnO2 nanowires.
Sci Rep
PUBLISHED: 08-15-2014
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We have studied the microstructure, surface states, valence fluctuations, magnetic properties, and exchange bias effect in MnO2 nanowires. High purity ?-MnO2 rectangular nanowires were synthesized by a facile hydrothermal method with microwave-assisted procedures. The microstructure analysis indicates that the nanowires grow in the [0 0 1] direction with the (2 1 0) plane as the surface. Mn(3+) and Mn(2+) ions are not found in the system by X-ray photoelectron spectroscopy. The effective magnetic moment of the manganese ions fits in with the theoretical and experimental values of Mn(4+) very well. The uncoupled spins in 3d(3) orbitals of the Mn(4+) ions in MnO6 octahedra on the rough surface are responsible for the net magnetic moment. Spin glass behavior is observed through magnetic measurements. Furthermore, the exchange bias effect is observed for the first time in pure ?-MnO2 phase due to the coupling of the surface spin glass with the antiferromagnetic ?-MnO2 matrix. These ?-MnO2 nanowires, with a spin-glass-like behavior and with an exchange bias effect excited by the uncoupled surface spins, should therefore inspire further study concerning the origin, theory, and applicability of surface structure induced magnetism in nanostructures.
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Higher levels of circulating monocyte-platelet aggregates are correlated with viremia and increased sCD163 levels in HIV-1 infection.
Cell. Mol. Immunol.
PUBLISHED: 08-11-2014
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Increased levels of monocyte-platelet aggregates (MPAs) are reported to be highly correlated with cardiovascular events. In this study, the MPA levels in different monocyte subsets and the associations between MPA levels, HIV-1 viremia and monocyte activation were evaluated during HIV-1 infection. The results showed that the percentages of MPAs in all three monocyte subsets were higher in HIV-1-infected subjects than in healthy controls, and were associated with the plasma viral load in the non-classical and intermediate monocyte subsets. The plasma levels of sCD14 and sCD163 were upregulated in HIV-1 infection and were positively associated with viral loads and negatively associated with CD4 counts. P-selectin glycoprotein ligand-1 (PSGL-1) was shown to be expressed at significantly lower levels on all three monocyte subsets and was negatively correlated with the sCD163 level. The MPA level was correlated with the levels of plasma sCD163 but negatively correlated with CD163 and PSGL-1 on all three monocyte subsets. An elevated immune activation status was correlated with increased MPA formation, underlying the potential interaction between monocyte activation and MPA formation. This interaction may be related to a higher thromboembolic risk in patients infected with HIV-1.Cellular & Molecular Immunology advance online publication, 11 August 2014; doi:10.1038/cmi.2014.66.
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Telecytopathology for on-site adequacy evaluation decreases the nondiagnostic rate in endoscopic ultrasound-guided fine-needle aspiration of pancreatic lesions.
Telemed J E Health
PUBLISHED: 08-05-2014
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Advances in digital imaging methods have resulted in use of telecytology in the immediate assessment of fine-needle aspiration (FNA) specimens. We retrospectively compared the nondiagnostic rate for endoscopic ultrasound-guided (EUS) FNA of pancreatic lesions in two groups: one with on-site evaluation for adequacy via telecytopathology and the other without on-site adequacy evaluation.
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The interaction of a cobalt porphyrin with cancer-associated nitrosamines.
Bioorg. Chem.
PUBLISHED: 07-31-2014
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A cobalt porphyrin (CY-B) was presented, and its interaction with tobacco-specific nitrosamines (TSNAs) was investigated by UV-Vis spectroscopy and high-resolution mass spectrometry. The results revealed that the stoichiometry of the host-guest interaction was 1:2 and that the binding constant between CY-B and TSNAs was within the range of 0.78×10(8)-7.83×10(8)M(-2). The coordination strength between CY-B and TSNAs decreased in the sequence of NNN>NAB>NAT>NNK based on the binding constant. The interaction mechanism of CY-B with TSNAs involved a coordination interaction, and the ?-? interaction between the porphyrin macrocycle and the aromatic frame of the TSNAs pyridines may also have been a driving force. The measured thermodynamic properties demonstrated that the reaction of CY-B with TSNAs was spontaneous and that the driving force for the interaction was a change in enthalpy. The reaction was exothermic, and an increasing temperature inhibited the interaction. The IR spectrum of the complex revealed that the NNO group of TSNAs and the metal cobalt of CY-B formed the six-coordinate complex.
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Molecular cloning, expression, and characterization of a Sophora alopecuroides lectin from Escherichia coli.
Acta Biochim. Biophys. Sin. (Shanghai)
PUBLISHED: 07-17-2014
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Sophora alopecuroides lectin (SAL) has been isolated from the seeds and confirmed to have antifungal and antitumor activities, and presently the preparation of the natural lectin was cumbersome, time-consuming, and the yield was relatively low for further analysis. In this study, the signal peptide of lectin, the modification sites, and the secondary structure were analyzed, and the three-dimensional structures of SAL were modeled. The gene of SAL was amplified by the reverse transcription polymerase chain reaction, and cloned into the pET-30a vector and expressed in Escherichia coli BL21(DE3) by the induction of isopropyl-beta-d-thiogalactopyranoside. Totally, 400 mg of recombinant SAL (rSAL) was purified from 1 l of bacterial culture through Ni-NTA agarose column and the purity reached 95%. The recombinant protein was further confirmed by western blot using rSAL-specific antibody. The biological activity analysis results showed that rSAL exclusively bound to d-galactose and had universal hemagglutinating activities to human A, B, O, and AB, and rabbit and mouse erythrocytes. rSAL also inhibited the growth of fungi, the proliferation of cancer cells, and the HIV-I reverse transcriptase activity. In conclusion, this study indicates that rSAL can be produced in large quantities in the prokaryotic expression system and the recombinant protein still retains the various biological activities, which will make the large-scale production of SAL recombinant protein at dramatically reduced cost possible.
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A comparative analysis of characteristic floral scent compounds in Prunus mume and related species.
Biosci. Biotechnol. Biochem.
PUBLISHED: 07-15-2014
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In order to investigate the difference in their characteristic floral scents between Prunus mume Siebold & Zucc. and the related Prunus species, their headspace volatiles and endogenous extraction were analyzed by gas chromatography-mass spectrometry. The efficiency of substrate utilization of the flowers was studied by incubating them with different alcohol substrates. Our results indicated that benzyl acetate is a dominant compound influencing the characteristic floral scent of P. mume. An alcohol substrate concentration of 4 mmol L(-1) and a reaction time of 2 h were constituted the reaction condition for catalysis of exogenous alcohol substrates by the flowers. Under these conditions, Prunus sibirica exhibited the highest utilization efficiency for benzyl alcohol substrate while the utilization efficiency of Prunus persica was the lowest. Comparative analysis of several alcohol substrates indicated that the flowers of the tested species had selective specificity for benzyl alcohol substrates.
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Hot pressing to enhance the transport Jc of Sr0.6K0.4Fe2As2 superconducting tapes.
Sci Rep
PUBLISHED: 07-14-2014
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High-performance Sr0.6K0.4Fe2As2 (Sr-122) tapes have been successfully fabricated using hot pressing (HP) process. The effect of HP temperatures (850-925°C) on the c-axis texture, resistivity, Vickers micro-hardness, microstructure and critical current properties has been systematically studied. Taking advantage of high degree of c-axis texture, well grain connectivity and large concentration of strong-pinning defects, we are able to obtain an excellent Jc of 1.2 × 10(5)?A/cm(2) at 4.2?K and 10?T for Sr-122 tapes. More importantly, the field dependence of Jc turns out to be very weak, such that in 14?T the Jc still remains ~ 1.0 × 10(5)?A/cm(2). These Jc values are the highest ever reported so far for iron-pnictide wires and tapes, achieving the level desired for practical applications. Our results clearly strengthen the position of iron-pnictide conductors as a competitor to the conventional and MgB2 superconductors for high field applications.
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Association between genetic polymorphisms of cytochrome P450 2C19 and the risk of cerebral ischemic stroke in Chinese.
BMC Med. Genet.
PUBLISHED: 07-09-2014
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Cytochrome P450 (CYP) 2C19 is a very important drug metabolizing enzyme. Although the single nucleotide polymorphisms (SNPs) of CYP2C19 G681A and G636A have been suggested that they may increase the incidence of cardiovascular events, the relationship between SNPs in CYP2C19 and cerebral ischemic stroke (CIS) are unclear. The aim of this study was to investigate the correlation between the distribution of G681A and G636A polymorphisms in CYP2C19 gene and the risk of CIS in Chinese.
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Impact of sequence variation in a dominant HLA-A*02-restricted epitope in hepatitis C virus on priming and cross-reactivity of CD8+ T cells.
J. Virol.
PUBLISHED: 07-09-2014
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CD8+ T cells are an essential component of successful adaptive immune responses against hepatitis C virus (HCV). A major obstacle to vaccine design against HCV is its inherent viral sequence diversity. Here, we test the hypothesis that different sequence variants of an immunodominant CD8+ T cell epitope, all binding with high affinity to HLA class I, target different T cell receptor repertoires and thereby influence the quality of the CD8+ T cell response. The impacts of sequence differences in the HLA-A*02-restricted HCV NS31406-1415 epitope on in vitro priming of naive CD8+ T cells from seronegative donors and cross-reactivity of primed T cells with other epitope variants were characterized. Although the six epitope variants tested were all high-affinity binders to HLA-A*02:01, substantial differences in priming and cross-reactivity of CD8+ T cells were observed. The variant associated with the most reproducible priming and induction of T cells with broad cross-reactivity was a genotype 1b variant (KLSALGLNAV) that is more common in HCV isolates collected in Asia but is rare in sequences from Europe and North America. The superior immunogenicity and cross-reactivity of this relatively rare epitope variant were confirmed by using HCV-specific memory CD8+ T cells from people who inject drugs, who are frequently exposed to HCV. Collectively, the data suggest that sequence differences at the epitope level between HCV isolates substantially impact CD8+ T cell priming and the degree of cross-reactivity with other epitope variants.
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Hg(II)-activated emission "turn-on" chemosensors excited by up-conversion nanocrystals: Synthesis, characterization and sensing performance.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 07-07-2014
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In this paper, two emission "turn-on" chemosensors for Hg(II) sensing were designed and synthesized. Up-conversion NaYF4 nanocrystals were prepared and used as the excitation host for both chemosensors. Spectral analysis suggested that there should be an efficient energy transfer between the host and the chemosensors, which was then confirmed by excited state lifetime analysis. Then two sensing systems using this up-conversion host and the two chemosensors were constructed, their sensing performance for Hg(II) ions was then studied. It was found that the probe emission intensity increased with increasing Hg(II) concentrations, showing an emission "turn-on" effect. Good selectivity and linear response were observed from both sensing systems.
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Physiological roles of asialoglycoprotein receptors (ASGPRs) variants and recent advances in hepatic-targeted delivery of therapeutic molecules via ASGPRs.
Protein Pept. Lett.
PUBLISHED: 07-01-2014
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The asialoglycoprotein receptor (ASGPR) is a high-capacity C-type lectin receptor mainly expressed on mammalian hepatic cells. The physiological function of ASGPR has not been completely clarified and is thought to be specific binding and internalization of galactose (Gal) or N-acetylgalactosamine (GalNAc)-terminating glycoproteins by hepatocytes. The human ASGPR is comprised of two homologous polypeptides, H1 and H2. ASGPR H1 has two splice variants (H1a and H1b) and ASGPR H2 has three splice variants (H2a, H2b, and H2c). These variants have been discovered to exist both in human liver tissues and in human hepatoma cells. Variant H1b, which has an in-frame deletion of exon 2 resulting in the loss of the transmembrane domain and is secreted as a soluble protein, encodes functional soluble ASGPR (s- ASGPR). Based on our previous results, we proposed the possible physiological function of s-ASGPR, which is well interpreted in the Galactosyl Homeostasis Hypothesis proposed by Weigel. ASGPR is one of the most promising targets for hepatic delivery. In this review, the recent progresses of cationic polysomes and liposomes as effective non-viral delivery system via ASGPR are also presented.
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Axl as a downstream effector of TGF-?1 via PI3K/Akt-PAK1 signaling pathway promotes tumor invasion and chemoresistance in breast carcinoma.
Tumour Biol.
PUBLISHED: 06-29-2014
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The invasion and chemoresistance are crucial causes of morbidity and death for cancer patients. Axl is closely associated with malignant phenotype of breast tumor cells, including invasiveness and metastasis. Both breast cancer cell line and tissue displayed increased expression of Axl, especially in highly metastatic breast cancer. On the contrary, experimental inhibition of Axl or transforming growth factor beta 1 (TGF-?1) by RNAi assay could suppress cell invasion ability and chemoresistance. Moreover, the up-regulation of Axl was induced by TGF-?1, further activated phosphatidylinositol 3-kinase (PI3K)/Akt and PAK1 translocation, and resulted in greater cell motility, invasion, and chemoresistance in vitro and in vivo. After the detection and statistics in human breast cancer specimens, we found that the Axl expression was closely correlated with TGF-?1 level, tumor differentiation, lymph node metastasis, and clinical stage (p?
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The opposite associations of long-chain versus very long-chain monounsaturated fatty acids with mortality among patients with coronary artery disease.
Heart
PUBLISHED: 06-25-2014
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Epidemiological evidence suggests that different lengths of carbon chains might predict cardiovascular disease (CVD) events differently. However, little data exist concerning the effects of specific types of monounsaturated fatty acids (MUFAs) stratified by chain length. Therefore, the study aimed to explore whether the associations of long-chain MUFAs (LC-MUFAs: 16:1n-7 and 18:1n-9) and very long-chain MUFAs (VLC-MUFAs: 20:1n-9, 22:1n-9 and 24:1n-9) with mortality were different among patients with coronary artery disease (CAD).
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Self-Assembly of Honeycomb-like MoS2 Nanoarchitectures Anchored into Graphene Foam for Enhanced Lithium-Ion Storage.
Adv. Mater. Weinheim
PUBLISHED: 06-19-2014
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Honeycomb-like MoS2 nanoarchitectures anchored into 3D graphene foam are successfully fabricated as a high-performance positive electrode for enhanced Li-ion storage. The unique 3D interpenetrating honeycomb-like structure is the key to the high performance. High reversible capacity, superior high-rate capability, and excellent cycling stability are demonstrated.
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Poly(I:C) treatment leads to interferon-dependent clearance of hepatitis B virus in a hydrodynamic injection mouse model.
J. Virol.
PUBLISHED: 06-11-2014
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We have previously shown that poly(I:C) activates murine hepatic cells to produce interferon (IFN) and suppresses hepatitis B virus (HBV) replication in vitro. Therefore, we addressed whether poly(I:C) is able to induce the clearance of HBV in vivo. The chronic HBV replication mouse model was established by the hydrodynamic injection (HI) of pAAV-HBV1.2 into the tail veins of wild-type and IFN-?/?R-, IFN-?-, and CXCR3-deficient C57BL/6 mice. Fourteen days post-HI of pAAV-HBV1.2, mice were administered poly(I:C) by intraperitoneal injection, intramuscular injection, or HI. Only treatment of poly(I:C) by HI led to HBV clearance in wild-type C57BL/6 mice. Serum HBsAg disappeared within 40 days postinfection (dpi) in mice that received poly(I:C) by HI, and this was accompanied by the appearance of anti-HBs antibodies. HBV-specific T-cell and antibody responses were significantly enhanced by HI of poly(I:C). HBV replication intermediates and HBcAg-positive hepatocytes were eliminated in the liver. HI of poly(I:C) induced the production of IFNs in mice and enhanced the levels of cytokines, IFN-stimulated genes, and T-cell markers in the liver. Importantly, poly(I:C)-induced HBV clearance was impaired in IFN-?/?R-, IFN-?-, and CXCR3-deficient mice, indicating that the induction of type I IFN and the stimulation and recruitment of T cells into the liver are essential for HBV clearance in this model. Taken together, the application of poly(I:C) by HI into the liver enhances innate and adaptive immune responses and leads to HBV clearance in an HBV mouse model, implicating the potential of intrahepatic Toll-like receptor 3 (TLR3) activation for the treatment of chronic hepatitis B patients.
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Facile method to enhance the adhesion of TiO? nanotube arrays to Ti substrate.
ACS Appl Mater Interfaces
PUBLISHED: 05-27-2014
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The weak adhesion of anodic TiO2 nanotube arrays (TNTAs) to the underlying Ti substrate compromises many promising applications. In this work, a compact oxide layer between TNTAs and Ti substrate is introduced by employing an additional anodization in a fluoride-free electrolyte. The additional anodization results in an about 200 nm thick compact layer near the nanotube bottoms. Scratch test demonstrates that the critical load of TNTAs with the compact oxide layer is a more than threefold increase in comparison with those without the compact layer. Moreover, this facile method can also improve the photoactivity and supercapacitor performances of TNTAs markedly.
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Effects of metronidazole on proopiomelanocortin a gene expression in zebrafish.
Gen. Comp. Endocrinol.
PUBLISHED: 05-19-2014
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The Metronidazole (MTZ), a widely used antibiotic for treating variations of infections, recently is applied in a powerful tool for specifically ablating cells or tissues when combined with E. coli nitroreductase (NTR). Although some undesired biological effects on eukaryote cells have been reported previously, the toxicological mechanism of MTZ has not been uncovered yet. In current study, we found that MTZ can induce proopiomelanocortin a (pomca) expression in zebrafish larvae. The effect of MTZ is in stage-sensitive and dose-dependent manner. A pro-proliferation activity of MTZ on pomca-expressing cells in the pituitary at larval stage was also observed. Furthermore, up-regulated levels of prolactin (prl) and glycoprotein hormone subunit ? (gsu?) were also observed after the MTZ treatment. Therefore, utilizing our zebrafish as in vivo model, we concluded that MTZ can interfere the endocrine signals in the pituitary hormone genes expression. Our current results raised the cautions to the intensively application of MTZ in clinical practices and biomedical researches.
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[Expression and significance of PTEN, P-ERK and P-AKT in the middle ear cholesteatoma].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 05-08-2014
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Detect the expressions of the protein tyrosine phosphatase gene (PTEN), phosphorylated protein kinase B (P-AKT) and phosphorylated extracellular signal-regulated kinase (P-ERK) in human middle ear cholesteatoma tissue and its correlation to explore their important role in the mechanism of the formation of cholesteatoma.
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Genome-wide identification, characterisation and expression analysis of the MADS-box gene family in Prunus mume.
Mol. Genet. Genomics
PUBLISHED: 05-06-2014
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MADS-box genes encode transcription factors that play crucial roles in plant development, especially in flower and fruit development. To gain insight into this gene family in Prunus mume, an important ornamental and fruit plant in East Asia, and to elucidate their roles in flower organ determination and fruit development, we performed a genome-wide identification, characterisation and expression analysis of MADS-box genes in this Rosaceae tree. In this study, 80 MADS-box genes were identified in P. mume and categorised into MIKC, M?, M?, M? and M? groups based on gene structures and phylogenetic relationships. The MIKC group could be further classified into 12 subfamilies. The FLC subfamily was absent in P. mume and the six tandemly arranged DAM genes might experience a species-specific evolution process in P. mume. The MADS-box gene family might experience an evolution process from MIKC genes to M? genes to M?, M? and M? genes. The expression analysis suggests that P. mume MADS-box genes have diverse functions in P. mume development and the functions of duplicated genes diverged after the duplication events. In addition to its involvement in the development of female gametophytes, type I genes also play roles in male gametophytes development. In conclusion, this study adds to our understanding of the roles that the MADS-box genes played in flower and fruit development and lays a foundation for selecting candidate genes for functional studies in P. mume and other species. Furthermore, this study also provides a basis to study the evolution of the MADS-box family.
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Hollow nickel nanocorn arrays as three-dimensional and conductive support for metal oxides to boost supercapacitive performance.
Nanoscale
PUBLISHED: 04-28-2014
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A novel three-dimensional (3D) metal/metal oxide core/branch array electrode has been fabricated as a supercapacitor electrode. Hollow Ni nanocorn arrays are constructed on Ni foams and act as a highly conductive and stable support to Co3O4 nanoflakes. Enhanced pseudocapacitive performance compared to bare Co3O4 nanosheets is demonstrated with high rate capability and excellent cycling stability.
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Circumcision plus antibiotic, anti-inflammatory, and ?-blocker therapy for the treatment for chronic prostatitis/chronic pelvic pain syndrome: a prospective, randomized, multicenter trial.
World J Urol
PUBLISHED: 04-26-2014
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The purpose of the study was to evaluate the efficacy of circumcision combined with antibiotic, anti-inflammatory, and ?-blocker therapy for the treatment for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS).
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Downregulation of homeodomain-interacting protein kinase-2 contributes to bladder cancer metastasis by regulating Wnt signaling.
J. Cell. Biochem.
PUBLISHED: 04-25-2014
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Homeodomain-interacting protein kinase-2 (Hipk2) has been shown to have important regulatory roles in cancer biology, such as cancer cell proliferation, cell cycle, and cell invasion. However, the contributions of Hipk2 to bladder cancer metastasis remain largely unknown. In the current study, we assayed the expression level of Hipk2 in bladder cancer tissues by real-time PCR, and defined its biological functions. We found that Hipk2 levels were downregulated in most bladder cancer tissues compared with adjacent normal tissues, and Hipk2 levels were remarkably decreased in metastasized tumor tissues when compared with primary tumors. SiRNA-mediated Hipk2 silencing increased bladder cancer cell invasion. Hipk2 knockdown resulted in decrease of E-cadherin expression and increase of N-cadherin and fibronectin expression, indicated that epithelial-mesenchymal transition (EMT) was induced. We further demonstrated that Hipk2 knockdown induced Wnt signaling activation and ?-catenin nuclear localization. Finally, we confirmed that Hipk2 inhibition promoted EMT and subsequent cell invasion, at least in part by activating Wnt signaling. These data suggest an important role of Hipk2 in regulating metastasis of bladder cancer and implicate the potential application of Hipk2 in bladder cancer therapy.
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[An alternative model of composite tissue transplantation in rat: the femur osteomyocutaneous flap].
Zhonghua Zheng Xing Wai Ke Za Zhi
PUBLISHED: 04-24-2014
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To reconstruct a simpler and reliable composite tissue transplantation model-the femur osteomyocutaneous flap for the replacement of hindlimb transplantation.
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Axl mediates tumor invasion and chemosensitivity through PI3K/Akt signaling pathway and is transcriptionally regulated by slug in breast carcinoma.
IUBMB Life
PUBLISHED: 04-17-2014
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The invasion and chemoresistance are crucial causes of morbidity and relapse for cancer patients. Axl is implicated in the modulation of cell invasion, cancer metastasis, and chemosensitivity in human breast carcinoma cell lines. Both breast cancer cell lines and tissues displayed increased expression of Axl, and it over expressed in highly metastatic breast cancer. The altered expression level of Axl was corresponding to the changed invasive phenotype and chemosensitivity of MDA-MB-231 cells both in vitro and in vivo. Further data indicated that experimental inhibition of Axl by RNAi assay inhibited phosphatidylinositol 3-kinase (PI3K)/Akt/GSK3? signaling pathway, resulted in the decrease of Slug expression, and further suppressed cell invasion properties and chemosensitivity. What is more, after the detection and statistics in human breast cancer specimens, we found the Axl expression was closely correlated with histological grade, lymph node metastasis, and clinical stage (P?
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Diversity and evolution of oligopeptide permease systems in staphylococcal species.
Genomics
PUBLISHED: 04-16-2014
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Several oligopeptide permease (Opp) systems have been found in staphylococcal species, including Opp1-4, Opp3' and the arginine catabolic mobile element (ACME)-encoded Opp system (ACME-Opp). They confer upon bacteria the increasing fitness, but their evolutionary histories remain unclear. In this work, we performed a genome-wide identification of Opp systems in staphylococcal species. Novel Opp systems were identified, including the duplicate of Opp4 in Staphylococcus pseudintermedius and the ACME-Opp-like systems in coagulase-negative staphylococci (CoNS). Phylogenetic analysis revealed that all of the identified Opp systems were derived from Opp3 system by operon duplication during species divergence, while lateral gene transfer might also confer to the dissemination of Opp in staphylococci. In addition, we proposed an improved theory on evolution of ACME: the Opp and arginine-deiminase systems were firstly transferred from Staphylococcus haemolyticus to Staphylococcus epidermidis independently; in S. epidermidis they were assembled together and then transferred to Staphylococcus aureus.
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Thulium laser versus standard transurethral resection of the prostate for benign prostatic obstruction: a systematic review and meta-analysis.
World J Urol
PUBLISHED: 04-13-2014
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To assess the efficacy and safety of thulium laser versus standard transurethral resection of the prostate (TURP) for treating patients with benign prostatic obstruction.
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Solution synthesis of metal oxides for electrochemical energy storage applications.
Nanoscale
PUBLISHED: 04-04-2014
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This article provides an overview of solution-based methods for the controllable synthesis of metal oxides and their applications for electrochemical energy storage. Typical solution synthesis strategies are summarized and the detailed chemical reactions are elaborated for several common nanostructured transition metal oxides and their composites. The merits and demerits of these synthesis methods and some important considerations are discussed in association with their electrochemical performance. We also propose the basic guideline for designing advanced nanostructure electrode materials, and the future research trend in the development of high power and energy density electrochemical energy storage devices.
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HIV risk perception among HIV negative or status-unknown men who have sex with men in China.
Biomed Res Int
PUBLISHED: 03-30-2014
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To evaluate HIV risk perception and its associated factors among Chinese MSM.
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Coenzyme Q10 promotes macrophage cholesterol efflux by regulation of the activator protein-1/miR-378/ATP-binding cassette transporter G1-signaling pathway.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 03-27-2014
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Recent studies have shown the role of miRNAs in macrophage reverse cholesterol transport and atherogenesis. We hypothesized that coenzyme Q10 (CoQ10) may increase macrophage reverse cholesterol transport by regulating miRNA expression that contributes to the prevention of atherosclerosis.
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[Investigation of vasopressin response to increasing osmotic pressure in the late-phase of septic shock patients].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 03-22-2014
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To investigate the vasopressin ( VP) response to increasing osmotic pressure in the late-phase of septic shock patients.
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Controlled self-assembly and photovoltaic characteristics of porphyrin derivatives on a silicon surface at solid-liquid interfaces.
Soft Matter
PUBLISHED: 03-21-2014
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Two meso-tetraphenylporphyrin (H2TPP) derivatives with different central metal ions, namely ZnTPP, CuTPP, were synthesized, and characterized by a series of spectroscopic methods. Their self-assembly behaviors in mixed solvents without surfactant were systematically investigated. The morphology of the thus produced nanoarchitectures could be efficiently controlled. Nanoslices can be manufactured when a volume of cyclohexane is involved, octahedrons can be produced when a mixed solvent of chloroform and isopropanol is employed, while four-leaf clover-shaped structures can be produced with a large volume of methanol injected. The nanostructures have been characterized by electronic absorption, scanning electron microscopy (SEM) and photoelectric conversion techniques. The internal structures of the nanostructures are well described by XRD. The nanostructures exhibit a power conversion under illumination intensity of 2.3 mW cm(-2). The present result appears to represent an effort toward controlling the morphology of self-assembled nanostructures of porphyrin derivatives via synthesis through introduction of metal-ligand and solvent interaction. Nevertheless, the fundamental study will be helpful to understand photoinduced energy/charge transport in an organic interface and this might also serve as promising building blocks for nanoscale power sources for potential application in solar energy technologies and organic electronics and optoelectronics.
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The supercritical CO? extract from the skin of Bufo bufo gargarizans Cantor blocks hepatitis B virus antigen secretion in HepG2.2.15 cells.
Biosci Trends
PUBLISHED: 03-21-2014
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The skin of Bufo bufo gargarizans Cantor has long been used for the treatment of hepatitis B in China and supercritical carbon dioxide extraction (SC-CO?) is widely used in extracting active ingredients from natural products. The aim of present study was to assess the anti-hepatitis B virus (HBV) effect of the supercritical CO? extract from the skin of Bufo bufo gargarizans Cantor (SCE-BC). Cytotoxicity of SCE-BC was analyzed using an MTT [3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide] assay in HepG2.2.15 cells. The hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), and hepatitis B core-related antigen (HBcrAg) concentrations in cell culture medium were determined by chemiluminescent enzyme immunoassay. HBV mRNA in cells was determined using real-time polymerase chain reaction. SCE-BC concentrations below 10(-2) ?g/mL had no significant toxicity to HepG2.2.15 cells. SCE-BC at 10(-4) ?g/mL effectively inhibited the secretion of HBeAg by 23.36% on day 6. It was more potent than the positive control lamivudine (100 ?g/mL) in terms of the inhibition of HBeAg and HBcrAg secretion on day 6. Consistent with the HBV antigen reduction, HBV mRNA expression was markedly inhibited in comparison to the control when HepG2.2.15 cells were treated with SCE-BC. Moreover, SCE-BC had greater inhibitory activity with respect to HBeAg than to HBsAg. Since HBeAg promotes immune tolerance and persistent infection during HBV infection, the present results suggest that immune tolerance induced by HBeAg might be overcome by SCE-BC. Therefore, SCE-BC warrants further investigation.
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Gold nanorod length controls dispersion, local ordering, and optical absorption in polymer nanocomposite films.
Soft Matter
PUBLISHED: 03-18-2014
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The dispersion, local orientation and optical absorption of polystyrene (PS, degree of polymerization P) nanocomposites containing PS-grafted gold nanorods (Au NRs, PS degree of polymerization N), with aspect ratios (? = length/diameter) ranging from 2.5 to 6.3, are studied using quantitative scanning electron microscopy (SEM) and optical spectroscopy. The experimentally observed nanorod assemblies and optical absorptions are compared with predictions from self-consistent field theory (SCFT) and finite difference time domain (FDTD) calculations, respectively. A pair correlation function for Au NRs is calculated from SEM images, and contains no correlation peaks for P/N = 0.9, indicating nanorods are dispersed within the nanocomposite. Large correlation peaks are observed for P/N = 7.6, representative of interparticle separation distances within nanorod aggregates, which do not vary with ?. On the basis of SCFT calculations, aggregation is attributed to significant depletion-attraction forces in the composite for P/N > 1. When Au NRs disperse, the longitudinal surface plasmon resonance (LSPR) peak red shifts from the visible into the near-IR as ? increases. No shift in the dispersed LSPR position is observed for v = 2.5 and 3.3 upon aggregation because the ratio of the interparticle distance to the nanorod length is too large for surface plasmon coupling. However, for v = 6.3, significant coupling between surface plasmons leads to a blue shift of the LSPR by approximately 140 nm, in agreement with FDTD calculations.
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Strongly enhanced current densities in Sr0.6K0.4Fe2As2 + Sn superconducting tapes.
Sci Rep
PUBLISHED: 03-11-2014
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Improving transport current has been the primary topic for practical application of superconducting wires and tapes. However, the porous nature of powder-in-tube (PIT) processed iron-based tapes is one of the important reasons for low critical current density (Jc) values. In this work, the superconducting core density of ex-situ Sr0.6K0.4Fe2As2 + Sn tapes, prepared from optimized precursors, was significantly improved by employing a simple hot pressing as an alternative route for final sintering. The resulting samples exhibited optimal critical temperature (Tc), sharp resistive transition, small resistivity and high Vickers hardness (Hv) value. Consequently, the transport Jc reached excellent values of 5.1 × 10(4)?A/cm(2) in 10?T and 4.3 × 10(4)?A/cm(2) in 14?T at 4.2?K, respectively. Our tapes also exhibited high upper critical field Hc2 and almost field-independent Jc. These results clearly demonstrate that PIT pnictide wire conductors are very promising for high-field magnet applications.
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Hyperplasia and cellularity changes in IGF-1-overexpressing skeletal muscle of crucian carp.
Endocrinology
PUBLISHED: 03-10-2014
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The zebrafish skeletal muscle-specific promoter mylz2 was used to cause crucian carp overexpression of the zebrafish IGF-1 cDNA. In stable transgenic germline F1 progenies, a 5-fold increase in the level of IGF-1 in skeletal muscle was observed. Evident skeletal muscle hyperplasia was observed in the transgenic fish through histologic analysis. By analyzing the RNA sequencing transcriptome of the skeletal muscle of IGF-1 transgenic fish and nontransgenic control fish at 15 months of age, 10 966 transcripts with significant expression levels were identified with definite gene descriptions based on the corresponding zebrafish genome information. Based on the results of our RNA sequencing transcriptome profiling analysis and the results of the real-time quantitative PCR analysis performed to confirm the skeletal muscle transcriptomics analysis, several pathways, including IGF-1 signaling, aerobic metabolism, and protein degradation, were found to be activated in the IGF-1-overexpressing transgenic fish. Intriguingly, our transcriptional expression and protein assays indicated that the overexpression of IGF-1 stimulated a significant shift in the myofiber type toward a more oxidative slow muscle type. Although the body weight was surprisingly decreased by IGF-1 transgenic expression, significantly higher oxygen consumption rates were measured in IGF-1-overexpressing transgenic fish compared with their nontransgenic control fish. These results indicate that the sustained overexpression of IGF-1 in crucian carp skeletal muscle promotes myofiber hyperplasia and cellularity changes, which elicit alterations in the body energy metabolism and skeletal muscle growth.
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Phyllodes tumor of the breast: role of Axl and ST6GalNAcII in the development of mammary phyllodes tumors.
Tumour Biol.
PUBLISHED: 03-08-2014
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Phyllodes tumor exhibits an aggressive growth. The expression of many biological markers has been explored to discriminate between different grades of phyllodes tumor and to predict their behavior. The purpose of this study was to evaluate the implications of Axl and ST6GalNAcII in phyllodes tumors. Real-time PCR, Western blot, and immunohistochemical were used to analyze differential expression of ST6GalNAcII and Axl in phyllodes tumor (PT) cell lines and tissue specimens. RNAi assay, ECM invasion assay, and tumorigenicity assay were used to analyze the altered expression of ST6GalNAcII gene effects on the expression of Axl and invasive ability of phyllodes tumor cells in vitro and in vivo. Compared to benign tumors, borderline and malignant ones showed a remarkable increase in mRNA levels of Axl and ST6GalNAcII gene, and it was higher in malignant tumor cells than in borderline tumor cells. When ST6GalNAcII was silenced, compared to the control, the expression level of Axl was significantly reduced in malignant tumor cell transfectants and knockdown of ST6GalNAcII gene significantly inhibited invasive activity in malignant tumor cells. The high expression of ST6GalNAcII and Axl was significantly correlated with tumor grade and distance metastasis by immunohistochemical analysis. Axl and ST6GalNAcII expression increases with increasing tumor grade in mammary phyllodes tumors. ST6GalNAc II might be participated in the glycosylation of Axl, and this Axl glycosylation may mediate the tumorigenicity, invasion, and distant metastasis of PT cells.
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Nitrite inhalants use and HIV infection among men who have sex with men in China.
Biomed Res Int
PUBLISHED: 03-02-2014
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This is the first study in China to examine the use of nitrite inhalants and its correlates among men who have sex with men (MSM) in Beijing, China.
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ST6GalNAcII mediates the invasive properties of breast carcinoma through PI3K/Akt/NF-?B signaling pathway.
IUBMB Life
PUBLISHED: 02-26-2014
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Metastasis of tumor cells is the most deadly attribute of breast cancer patients. Aberrant sialylation is closely associated with malignant phenotype of tumor cells, including invasiveness and metastasis. The objective of this study is to clarify the possible role and mechanism of ST6GalNAcII in the metastasis process of breast carcinoma. Real-time PCR, Western blot, and immunohistochemical were used to analyze differential expression of ST6GalNAc II in breast carcinoma cell lines and tissue specimens. PI3K/AKt signaling pathway was also analyzed. The high expression level of ST6GalNAcII was corresponding to invasive phenotype of breast cancer cells both in vitro and in vivo. Further data indicated that manipulation of ST6GalNAcII gene expression led to alter the activity of phosphoinositide-3 kinase (PI3K)/Akt signaling pathway. Blocking the PI3K/Akt pathway resulted in reduced capacity in invasion of MDA-MB-231 cells. ST6GalNAcII elucidated the unusual properties of invasion in breast cancer cell via modulating the PI3K/AKt signaling pathway.
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Mifepristone modulates serotonin transporter function.
Neural Regen Res
PUBLISHED: 02-24-2014
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Regulating serotonin expression can be used to treat psychotic depression. Mifepristone, a glucocorticoid receptor antagonist, is an effective candidate for psychotic depression treatment. However, the underlying mechanism related to serotonin transporter expression is poorly understood. In this study, we cloned the human brain serotonin transporter into Xenopus oocytes, to establish an in vitro expression system. Two-electrode voltage clamp recordings were used to detect serotonin transporter activity. Our results show that mifepristone attenuates serotonin transporter activity by directly inhibiting the serotonin transporter, and suggests that the serotonin transporter is a pharmacological target of mifepristone for the treatment of psychotic depression.
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Serum lipids, apolipoproteins, and mortality among coronary artery disease patients.
Biomed Res Int
PUBLISHED: 02-24-2014
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The proatherogenic effect of low-density lipoprotein cholesterol (LDL-C) and antiatherogenic effect of high-density lipoprotein cholesterol (HDL-C) have been confirmed in general population. But controversy arises among coronary artery disease (CAD) patients. The goal of this study was to identify the association of different lipid measurements with CAD prognosis. The study cohort included 1916 CAD patients who were 40-85 years of age. Cox proportional hazards regression models were used to estimate the association of baseline 6 lipid factors and 3 ratios with all-cause and cardiovascular (CVD) mortality. During a median follow-up of 3.1 years, 147 deaths were recorded, 113 of which were due to CVD. When lipid factors were categorized, HDL-C showed a U-shape association with all-cause and CVD mortality after adjustment for major CVD risk factors. Serum LDL-C, apoB, LDL/HDL ratio, and apoB/apoA-I ratio were positively, and apoA-I level was inversely associated with the risk of CVD mortality. After further pairwise comparison of lipid-related risk, LDL/HDL ratio and LDL-C had stronger association with all-cause and CVD mortality than other proatherogenic measurements among Chinese CAD patients.
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A new type of porous graphite foams and their integrated composites with oxide/polymer core/shell nanowires for supercapacitors: structural design, fabrication, and full supercapacitor demonstrations.
Nano Lett.
PUBLISHED: 02-20-2014
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We attempt to meet the general design requirements for high-performance supercapacitor electrodes by combining the strategies of lightweight substrate, porous nanostructure design, and conductivity modification. We fabricate a new type of 3D porous and thin graphite foams (GF) and use as the light and conductive substrates for the growth of metal oxide core/shell nanowire arrays to form integrated electrodes. The nanowire core is Co3O4, and the shell is a composite of conducting polymer (poly(3,4-ethylenedioxythiophene), PEDOT) and metal oxide (MnO2). To show the advantage of this integrated electrode design (viz., GF + Co3O4/PEDOT-MnO2 core/shell nanowire arrays), three other different less-integrated electrodes are also prepared for comparison. Full supercapacitor devices based on the GF + Co3O4/PEDOT-MnO2 as positive electrodes exhibit the best performance compared to other three counterparts due to an optimal design of structure and a synergistic effect.
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Nucleoside analogues alone or combined with vaccination prevent hepadnavirus viremia and induce protective immunity: alternative strategy for hepatitis B virus post-exposure prophylaxis.
Antiviral Res.
PUBLISHED: 02-18-2014
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The current strategies for hepatitis B virus (HBV) post-exposure prophylaxis (PEP) are not generally available in remote and rural areas of developing countries and/or carry potential risks for infection with blood-borne transmitted pathogens. Nucleotide analogues (NAs) are successfully used for human immunodeficiency virus PEP, and maybe effective for HBV PEP. In this study, we tested the NA-based strategies for HBV PEP using the Chinese woodchuck model.
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A V2O5/conductive-polymer core/shell nanobelt array on three-dimensional graphite foam: a high-rate, ultrastable, and freestanding cathode for lithium-ion batteries.
Adv. Mater. Weinheim
PUBLISHED: 02-14-2014
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A thin polymer shell helps V2O5 a lot. Short V2O5 nanobelts are grown directly on 3D graphite foam as a lithium-ion battery (LIB) cathode material. A further coating of a poly(3,4-ethylenedioxythiophene) (PEDOT) thin shell is the key to the high performance. An excellent high-rate capability and ultrastable cycling up to 1000 cycles are demonstrated.
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Propofol selectively inhibits nuclear factor-?B activity by suppressing p38 mitogen-activated protein kinase signaling in human EA.hy926 endothelial cells during intermittent hypoxia/reoxygenation.
Mol Med Rep
PUBLISHED: 02-04-2014
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Intermittent hypoxia/reoxygenation (IHR) induces proinflammatory cytokines, contributing to the pathogenic process of atherosclerosis associated with obstructive sleep apnea (OSA). Two transcription factors, nuclear factor-?B (NF-?B) and hypoxia-inducible factor-1 (HIF-1), have been indicated to mediate proinflammatory cytokines during IHR. The anti-inflammatory effects of propofol have attracted increasing attention in regard to the treament of multiple diseases associated with inflammation. The present study examined whether propofol inhibits NF-?B and HIF-1 activity in vascular endothelial cells during IHR. EA.hy926 endothelial cells were exposed to IHR for 64 cycles with or without propofol treatment. Gene knockdown by transfection of siRNA against p38 mitogen-activated protein kinase (MAPK) was also used to investigate the molecular mechanisms. Compared with the control group, IHR exposure significantly induced the activation of NF-?B and HIF-1, enhanced the mRNA expression of proinflammatory cytokines and increased the activation of p38 MAPK. Propofol dose-dependently inhibited the IHR?induced activation of NF-?B, but did not change the activation of HIF-1, which was accompanied by decreased levels of proinflammatory cytokines. In addition, IHR?induced p38 MAPK activity was attenuated by propofol in a similar manner to the reduction in NF-?B activity. Furthermore, knockdown of p38 MAPK with siRNA significantly reduced the IHR?induced activation of NF-?B, while not affecting HIF-1. These data demonstrate that propofol selectively attenuates the IHR?induced activation of NF-?B, but not HIF-1, in vascular endothelial cells, and these beneficial effects are likely to be based on the inhibition of the p38 MAPK signaling pathway. Propofol may have the potential to prevent atherosclerosis in patients with OSA by inhibiting NF-?B?mediated inflammation in the vascular endothelium.
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Stable cell line of human SH-SY5Y uniformly expressing TWIK-related acid-sensitive potassium channel and eGFP fusion.
Appl. Biochem. Biotechnol.
PUBLISHED: 01-29-2014
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TWIK-related acid-sensitive potassium channels (TASK3) are pharmacological targets of CNS inflammation induced by acidification. They function as molecular switches between survival and death of neurons. In this report, TASK3 cloned from human brain cDNA was tagged with enhanced green fluorescent protein (eGFP), and the fusion gene was transiently expressed in human neuroblastoma SH-SY5Y cells. A cell line stably expressing TASK-eGFP fusion proteins was generated from transient expression cells by using fluorescence-activated cell sorting followed by antibiotic selection. The uniform expression of TASK3 fusion proteins was further confirmed by flow cytometry. Moreover, the localization of TASK3 tagged with eGFP was checked by confocal microcopy. TASK3-eGFP fusion proteins are observed on the SH-SY5Y cell membrane. The strategies using eGFP as a fusion tag facilitate the monitoring of the TASK3 expression and enable the successful employment of FACS for screening and construction of cell lines stably expressing TASK3. The TASK3 overexpression cell line will lay a fundamental for the in vitro evaluation of TASK3 function during hypoxic/ischemic injury.
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Hematopoietic effects and mechanisms of Fufang e?jiao jiang on radiotherapy and chemotherapy-induced myelosuppressed mice.
J Ethnopharmacol
PUBLISHED: 01-11-2014
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Fufang e?jiao jiang (FEJ), which has been widely used in clinic to replenish qi (vital energy) and nourish blood, is a famous traditional Chinese medicine formula made up of Colla corii asini (donkey-hide gelatin prepared by stewing and concentrating from the hide of Equus asinus Linnaeus.), Radix codonopsis pilosulae (the root of Codonopsis pilosula (Franch.) Nannf.), Radix ginseng rubra (the steamed and dried root of Panax ginseng C.A. Mey.), Fructus crataegi (the fruit of Crataegus pinnatifida Bunge) and Radix rehmanniae preparata (the steamed and sun dried tuber of Rehmannia glutinosa (Gaertn.) Libosch. ex Fisch. & C.A. Mey.). The present study aimed to investigate the hematopoietic effects of FEJ on myelosuppressed mice induced by radiotherapy and chemotherapy systematically and to explore the underlying hematopoietic regulation mechanisms.
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Prevalence of HIV and syphilis infection among men who have sex with men in China: a meta-analysis.
Biomed Res Int
PUBLISHED: 01-06-2014
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To figure out the most current prevalence of HIV and syphilis in MSM in China.
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Fine Epitope Mapping of the Central Immunodominant Region of Nucleoprotein from Crimean-Congo Hemorrhagic Fever Virus (CCHFV).
PLoS ONE
PUBLISHED: 01-01-2014
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Crimean-Congo hemorrhagic fever (CCHF), a severe viral disease known to have occurred in over 30 countries and distinct regions, is caused by the tick-borne CCHF virus (CCHFV). Nucleocapsid protein (NP), which is encoded by the S gene, is the primary antigen detectable in infected cells. The goal of the present study was to map the minimal motifs of B-cell epitopes (BCEs) on NP. Five precise BCEs (E1, 247FDEAKK252; E2a, 254VEAL257; E2b, 258NGYLNKH264; E3, 267EVDKA271; and E4, 274DSMITN279) identified through the use of rabbit antiserum, and one BCE (E5, 258NGYL261) recognized using a mouse monoclonal antibody, were confirmed to be within the central region of NP and were partially represented among the predicted epitopes. Notably, the five BCEs identified using the rabbit sera were able to react with positive serum mixtures from five sheep which had been infected naturally with CCHFV. The multiple sequence alignment (MSA) revealed high conservation of the identified BCEs among ten CCHFV strains from different areas. Interestingly, the identified BCEs with only one residue variation can apparently be recognized by the positive sera of sheep naturally infected with CCHFV. Computer-generated three-dimensional structural models indicated that all the antigenic motifs are located on the surface of the NP stalk domain. This report represents the first identification and mapping of the minimal BCEs of CCHFV-NP along with an analysis of their primary and structural properties. Our identification of the minimal linear BCEs of CCHFV-NP may provide fundamental data for developing rapid diagnostic reagents and illuminating the pathogenic mechanism of CCHFV.
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Analysis of molecular cytogenetic alteration in rhabdomyosarcoma by array comparative genomic hybridization.
PLoS ONE
PUBLISHED: 01-01-2014
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Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue sarcoma with poor prognosis. The genetic etiology of RMS remains largely unclear underlying its development and progression. To reveal novel genes more precisely and new therapeutic targets associated with RMS, we used high-resolution array comparative genomic hybridization (aCGH) to explore tumor-associated copy number variations (CNVs) and genes in RMS. We confirmed several important genes by quantitative real-time polymerase chain reaction (QRT-PCR). We then performed bioinformatics-based functional enrichment analysis for genes located in the genomic regions with CNVs. In addition, we identified miRNAs located in the corresponding amplification and deletion regions and performed miRNA functional enrichment analysis. aCGH analyses revealed that all RMS showed specific gains and losses. The amplification regions were 12q13.12, 12q13.3, and 12q13.3-q14.1. The deletion regions were 1p21.1, 2q14.1, 5q13.2, 9p12, and 9q12. The recurrent regions with gains were 12q13.3, 12q13.3-q14.1, 12q14.1, and 17q25.1. The recurrent regions with losses were 9p12-p11.2, 10q11.21-q11.22, 14q32.33, 16p11.2, and 22q11.1. The mean mRNA level of GLI1 in RMS was 6.61-fold higher than that in controls (p?=?0.0477) by QRT-PCR. Meanwhile, the mean mRNA level of GEFT in RMS samples was 3.92-fold higher than that in controls (p?=?0.0354). Bioinformatic analysis showed that genes were enriched in functions such as immunoglobulin domain, induction of apoptosis, and defensin. Proto-oncogene functions were involved in alveolar RMS. miRNAs that located in the amplified regions in RMS tend to be enriched in oncogenic activity (miR-24 and miR-27a). In conclusion, this study identified a number of CNVs in RMS and functional analyses showed enrichment for genes and miRNAs located in these CNVs regions. These findings may potentially help the identification of novel biomarkers and/or drug targets implicated in diagnosis of and targeted therapy for RMS.
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Susceptibility of different hepatitis B virus isolates to interferon-alpha in a mouse model based on hydrodynamic injection.
PLoS ONE
PUBLISHED: 01-01-2014
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Interferon alpha (IFN-?) is commonly used for the treatment of chronic hepatitis B (CHB) patients. Many factors including viral genetics may determine the outcome of IFN-? therapy. In this study, we tested whether the expression of IFN-? directly in the liver inhibits HBV gene expression and replication using a HBV hydrodynamic injection (HI) mouse model. Two replication-competent clones from different HBV isolates that belonging to HBV genotype A and B based on a pAAV vector (pAAV-HBV-A and pAAV-HBV-B) were compared for their susceptibility to IFN-?. HBV clones were injected into mice either alone or in combination with a murine (m) IFN-? expression plasmid (pmIFN-?). HBsAg and HBeAg concentrations and HBV DNA levels in mice differed after injection of these two HBV clones. Co-application of pmIFN-? together with the two distinct isolates resulted in markedly different kinetics of decline of HBsAg, HBeAg, and HBV DNA levels in the mice. Immunohistochemical staining of liver sections with anti-HBc showed that mIFN-? application completely inhibited the expression of HBcAg in mice inoculated with pAAV-HBV-B, whereas the expression of HBcAg was only reduced in mice with pAAV-HBV-A. Consistently, mice injected with pAAV-HBV-B and pmIFN-? showed higher expression levels of the IFN-stimulated genes (ISGs) ISG15, OAS, PKR as well as proinflammatory cytokine IL-6 in the liver. In addition, expression levels of anti-inflammatory cytokine IL-10 was down-regulated significantly in liver of the mice injected with pAAV-HBV-B and pmIFN-?. Our data demonstrate that IFN-? exerts antiviral activity in HBV mouse model, but different HBV isolates may have diverse susceptibility to IFN-?.
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Chromosomal and genetic imbalances in Chinese patients with rhabdomyosarcoma detected by high-resolution array comparative genomic hybridization.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma in children. Although associations between ARMS tumorigenesis and PAX3, PAX7, and FKHR are well recognized, the complete genetic etiology underlying RMS pathogenesis and progression remains unclear. Chromosomal copy number variations (CNVs) and the involved genes may play important roles in the pathogenesis and progression of human malignancies. Using high-resolution array comparative genomic hybridization (aCGH), we examined 20 formalin-fixed, paraffin-embedded (FFPE) RMS tumors to explore the involvement of the relevant chromosomal regions with resident genes in RMS tumorigenesis. In RMS, frequent gains were identified on chromosome regions 12q13.3-q14.1, 12q24.31, 17q25.1, 1q21.1, and 7q11.23, whereas frequent losses were observed on chromosome regions 5q13.2, 14q32.33, and 15q11.2. Amplifications were observed on chromosome regions 9p13.3, 12q13.3-q14.1, 12q15, and 16p13.11, whereas deletions were detected on chromosome regions 1p36.33, 1p13.1, 2q11.1, 5q13.2, 8p23.1, 9p24.3, and 16p11.2. Frequent gains were detected in GLI1, GEFT, OS9, and CDK4 (12q13.3-q14.1), being 60% in embryonal rhabdomyosarcoma (ERMS) and 66.67% in alveolar rhabdomyosarcoma (ARMS), respectively. However, frequent losses were detected in IGHG1, IGHM, IGHG3, and IGHG4 (14q32.33), being 70% in ERMS and 55.56% in and ARMS, respectively. Frequent gains were detected in TYROBP, HCST, LRFN3, and ALKBH6 (19q13.12) in ERMS but not in ARMS. The frequency of TYROBP, HCST, LRFN3, and ALKBH6 gains is significantly different in ERMS versus ARMS (P=0.011). The results suggest that novel TYROBP, HCST, LRFN3, and ALKBH6 genes may play important roles in ERMS. The technique used is a feasible approach for array comparative genomic hybridization analysis in archival tumor samples.
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Characterization of the staphylococcal cassette chromosome composite island of Staphylococcus haemolyticus SH32, a methicillin-resistant clinical isolate from China.
PLoS ONE
PUBLISHED: 01-01-2014
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Staphylococcal cassette chromosome (SCC) elements contribute considerably to virulence and resistance to antibiotic agents in staphylococci. SCC elements in coagulase-negative staphylococci (CoNS) are highly diverse and there is evidence suggesting that they serve as a reservoir for antibiotic resistance genes in methicillin-resistant Staphylococcus aureus (MRSA). However, only a small number of SCC elements have been characterized in CoNS and their exact roles in the emergence and evolution of MRSA remain to be demonstrated. Here, we determined the structure of an SCC composite island (CISH32) found in the clinical Staphylococcus haemolyticus isolate SH32 by whole-genome DNA sequencing. CISH32 was 48 kb in length and mainly composed of two imperfect SCC elements, namely (i) a ?SCCmec(SH32) part containing a class C1 mec gene complex but lacking ccr genes and (ii) a SCCSH32 part with a ccrA5B3 gene complex but lacking mec genes. In addition, CISH32 contained a type III restriction-modification system and several resistance loci, for example genes conferring resistance to cadmium and arsenic. ?SCCmec(SH32) is almost entirely identical to a pseudo SCCmec element found in S. haemolyticus WCH1 and shares pronounced sequence similarity to a ?SCCmec element of S. haemolyticus JCSC1435. However, staphylococci other than S. haemolyticus, including S. aureus and S. epidermidis, contain homologs of SCCSH32 that are more similar to SCCSH32 than those elements found in S. haemolyticus, suggesting that CISH32 of S. haemolyticus SH32 was assembled in recent evolutionary events. Moreover, the composite structure of CISH32 indicates that the detection of class C1 mec and ccrA5B3 gene complexes in S. haemolyticus does not always indicate the existence of a UT9-type SCCmec element, which has remained questionable.
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Immunosuppressive drugs modulate the replication of hepatitis B virus (HBV) in a hydrodynamic injection mouse model.
PLoS ONE
PUBLISHED: 01-01-2014
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Hepatitis B virus (HBV) reactivation and recurrence are common in patients under immunosuppression and can be controlled by hepatitis B immunoglobulin, antivirals, and hepatitis B vaccine. However, the detailed analysis of HBV infection under immunosuppression is essential for the prophylaxis and therapy for HBV reactivation and recurrence. In this study, HBV replication and T cell responses were analyzed in a HBV-transfected mouse model under immunosuppressive therapy. During the treatment, HBV replication was at a high level in mice treated with dexamethasone, cyclosporine, and cyclophosphamide, whereas was terminated in mice treated with mycophenolate mofetil. After the withdrawal, HBV replication was at low or high levels in the dexamethasone-treated mice or in both cyclosporine- and cyclophosphamide-treated mice. The early withdrawal of cyclosporine allowed the recovery of suppressed T cell responses and led to subsequent HBV clearance, while the adoptive immune transfer to the mice with HBV persistence led to HBV suppression. Taken together, long-term HBV persistence under immunosuppression depends on the immunosuppressive drugs used and on the treatment duration and is mediated by the suppressed intrahepatic CD8 T cell response. These data may be helpful for individualized immunosuppressive therapy in patients with high risk of HBV reactivation and recurrence, and the mouse system is suitable for studying HBV reactivation and recurrence under immunosuppression.
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Enhancing virus-specific immunity in vivo by combining therapeutic vaccination and PD-L1 blockade in chronic hepadnaviral infection.
PLoS Pathog.
PUBLISHED: 01-01-2014
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Hepatitis B virus (HBV) persistence is facilitated by exhaustion of CD8 T cells that express the inhibitory receptor programmed cell death-1 (PD-1). Improvement of the HBV-specific T cell function has been obtained in vitro by inhibiting the PD-1/PD-ligand 1 (PD-L1) interaction. In this study, we examined whether in vivo blockade of the PD-1 pathway enhances virus-specific T cell immunity and leads to the resolution of chronic hepadnaviral infection in the woodchuck model. The woodchuck PD-1 was first cloned, characterized, and its expression patterns on T cells from woodchucks with acute or chronic woodchuck hepatitis virus (WHV) infection were investigated. Woodchucks chronically infected with WHV received a combination therapy with nucleoside analogue entecavir (ETV), therapeutic DNA vaccination and woodchuck PD-L1 antibody treatment. The gain of T cell function and the suppression of WHV replication by this therapy were evaluated. We could show that PD-1 expression on CD8 T cells was correlated with WHV viral loads during WHV infection. ETV treatment significantly decreased PD-1 expression on CD8 T cells in chronic carriers. In vivo blockade of PD-1/PD-L1 pathway on CD8 T cells, in combination with ETV treatment and DNA vaccination, potently enhanced the function of virus-specific T cells. Moreover, the combination therapy potently suppressed WHV replication, leading to sustained immunological control of viral infection, anti-WHs antibody development and complete viral clearance in some woodchucks. Our results provide a new approach to improve T cell function in chronic hepatitis B infection, which may be used to design new immunotherapeutic strategies in patients.
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Novel woodchuck hepatitis virus (WHV) transgene mouse models show sex-dependent WHV replicative activity and development of spontaneous immune responses to WHV proteins.
J. Virol.
PUBLISHED: 11-20-2013
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The woodchuck model is an informative model for studies on hepadnaviral infection. In this study, woodchuck hepatitis virus (WHV) transgenic (Tg) mouse models based on C57BL/6 mice were established to study the pathogenesis associated with hepadnaviral infection. Two lineages of WHV Tg mice harboring the WHV wild-type (1217) and a mutated WHV genome lacking surface antigen (1281) were generated. WHV replication intermediates were detected by Southern blotting. DNA vaccines against WHV proteins were applied by intramuscular injection. WHV-specific immune responses were analyzed by flow cytometry and ELISA. The presence of WHV transgenes resulted in liver-specific but sex- and age- dependent WHV replication in Tg mice. Pathological changes in the liver including hepatocellular dysplasia were observed in aged Tg mice, suggesting that the presence of WHV transgenes may lead to liver diseases. Interestingly, Tg mice of the lineage 1281 spontaneously developed T- and B-cell responses to WHV core protein (WHcAg). DNA vaccination induced specific immune responses to WHV proteins in WHV Tg mice, indicating the tolerance break. The magnitude of the induced WHcAg-specific immune responses was dependent on the effectiveness of different DNA vaccines and was associated with a decrease in WHV loads in mice. In conclusion, sex- and age-dependent viral replication, development of autoimmune responses to viral antigens, pathological changes in the liver in the WHV Tg mice and the possibility of breaking immune tolerance to WHV transgenes will allow future studies on pathogenesis related to hepadnaviral infection and therapeutic vaccines.
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TLR1/2 Ligand-Stimulated Mouse Liver Endothelial Cells Secrete IL-12 and Trigger CD8+ T Cell Immunity In Vitro.
J. Immunol.
PUBLISHED: 11-13-2013
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Liver sinusoidal endothelial cells (LSECs) are unique organ-resident APCs capable of Ag cross-presentation and subsequent tolerization of naive CD8(+) T cells. Under certain conditions, LSECs can switch from a tolerogenic to an immunogenic state and promote the development of T cell immunity. However, little is known about the mechanisms of LSECs to induce T cell immunity. In this study, we investigated whether functional maturation of LSECs can be achieved by TLR ligand stimulation and elucidated the mechanisms involved in LSEC-induced T cell immunity. We demonstrate that pretreatment of LSECs with palmitoyl-3-cysteine-serine-lysine-4 (P3C; TLR1/2 ligand) but not poly(I:C) (TLR3 ligand) or LPS (TLR4 ligand) reverted their suppressive properties to induce T cell immunity. Importantly, P3C stimulation caused functional maturation of Ag-presenting LSECs and enabled them to activate virus-specific CD8(+) T cells. The LSEC-mediated CD8(+) T cell immunity was initiated by soluble mediators, one of which was IL-12 secreted at a low but sustained level after P3C stimulation. P3C stimulation did not induce programmed death ligand 1 expression on LSECs, thereby favoring T cell proliferation and activation instead of suppression. Our data suggest that LSECs undergo maturation exclusively in response to TLR1/2 ligand stimulation and that the immunological status of LSECs was dependent upon the balance between programmed death ligand 1 and IL-12 expression. These results have implications for our understanding of liver-specific tolerance and autoimmunity and for the development of strategies to overcome T cell tolerance in situations such as chronic viral liver infections or liver cancer.
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Relationship between the tibial mechanical axis and bony anatomical landmarks of the calf and foot as measured on radiographs obtained with a new laser-calibrated position.
J Xray Sci Technol
PUBLISHED: 11-07-2013
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To investigate relationship between the tibial mechanical axis and bony landmarks of the calf and foot by developing a new laser-calibrated position for radiography of the lower limb.
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HIV vulnerabilities and coercive sex at same-sex sexual debut among men who have sex with men in Beijing, China.
AIDS Care
PUBLISHED: 10-08-2013
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Few studies have examined coercive sex and HIV vulnerabilities among men who have sex with men (MSM) in China. The present study seeks to compare individual characteristics between MSM who did and did not experience coercive sex at their MSM sexual debut and to identify HIV risk factors correlated with coercive sex at MSM sexual debut. In 2007, we recruited 167 MSM in Beijing, China by peer-referred social network sampling. Each participant then completed self-administered questionnaires regarding their sexual experiences and practices. Results show that 14% of participants reported coercive sex at MSM sexual debut, of whom 48% reported recent unprotected anal intercourse (UAI). Coercive sex at MSM sexual debut was significantly associated with UAI [adjusted odds ratio (AOR): 5.38, 95% confidence interval: 1.95-14.87] and lifetime number of male sex partners (AOR: 7.25, 95% CI: 2.39-22.01). Coercive sex is harming MSM in China and should be immediately addressed by researchers, public health officials, and MSM community stakeholders.
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A controllable approach to development of multi-spectral conjugated polymer nanoparticles with increased emission for cell imaging.
Chem. Commun. (Camb.)
PUBLISHED: 10-08-2013
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The authors demonstrate a smart and versatile approach for preparing multi-spectral conjugated polymers from a commercial precursor MEH-PPV without tedious synthetic modification. Multi-color CPNs with small size have also been successfully prepared using a modified-reprecipitation procedure for live cell imaging.
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Quadrangular Prism: A Unique Self-Assembly from Amphiphilic Hyperbranched PMA-b-PAA.
Macromol Rapid Commun
PUBLISHED: 09-27-2013
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The novel hyperbranched poly(methyl acrylate)-block-poly(acrylic acid)s (HBPMA-b-PAAs) are successfully synthesized via single-electron transfer-living radical polymerization (SET-LRP), followed with hydrolysis reaction. The copolymer solution could spontaneously form unimolecular micelles composed of the hydrophobic core (PMA) and the hydrophilic shell (PAA) in water. Results show that the size of spherical particles increases from 8.18 to 19.18 nm with increased pH from 3.0 to 12.0. Most interestingly, the unique regular quadrangular prisms with the large microstructure (5.70 ?m in length, and 0.47 ?m in width) are observed by the self-assembly of unimolecular micelles when pH value is below 2. Such self-assembly behavior of HBPMA-b-PAA in solution is significantly influenced by the pH cycle times and concentration, which show that increased polymer concentration favors aggregate growth.
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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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