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Find video protocols related to scientific articles indexed in Pubmed.
Enhancement of the field emission from the TiO2 nanotube arrays by reducing in a NaBH4 solution.
ACS Appl Mater Interfaces
PUBLISHED: 11-20-2014
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A mass of oxygen vacancies are successfully introduced into TiO2 nanotube arrays using low-cost NaBH4 as a reductant in a liquid-phase environment. By controlling and adjusting the reduction time over the range of 0-24 h, the doping concentration of the oxygen vacancy realizes controllable and eventually reaches saturation. Meanwhile, the thermal stability of oxygen vacancies is also investigated, indicating that part of oxygen vacancies remain stable up to 250 °C. In addition, this liquid-phase reduction strategy significantly lowers the requirements of instruments and cost. More interesting, reduced TiO2 nanotube arrays show drastically enhanced field emission performances including substantially decreased turn-on field from 25.01 to 2.65 V/?m, a high current density of 3.5 mA/cm2 at 7.2 V/?m and an excellent field emission stability and repeatability. These results are attributed to the oxygen vacancies obtained by reducing in NaBH4 solution, resulting in a reduced effective work function and an increased conductivity.
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Examining air pollution in China using production- and consumption-based emissions accounting approaches.
Environ. Sci. Technol.
PUBLISHED: 11-18-2014
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Two important reasons for China's air pollution are the high emission factors (emission per unit of product) of pollution sources and the high emission intensity (emissions per unit of GDP) of the industrial structure. Therefore, a wide variety of policy measures, including both emission abatement technologies and economic adjustment, must be implemented. To support such measures, this study used the production- and consumption-based emissions accounting approaches to simulate the SO2, NOx, PM2.5, and VOC emissions flows among producers and consumers. This study analyzed the emissions and GDP performance of 36 production sectors. The results showed that the equipment, machinery, and devices manufacturing and construction sectors contributed more than 50% of air pollutant emissions, and most of their products were used for capital formation and export. The service sector had the lowest emission intensities, and its output was mainly consumed by households and the government. In China, the emission intensities of production activities triggered by capital formation and export were approximately twice that of the service sector triggered by final consumption expenditure. This study suggests that China should control air pollution using the following strategies: applying end-of-pipe abatement technologies and using cleaner fuels to further decrease the emission factors associated with rural cooking, electricity generation, and the transportation sector; continuing to limit highly emission-intensive but low value-added exports; developing a plan to reduce construction activities; and increasing the proportion of service GDP in the national economy.
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[Effect of wound healing of orthopedic surgery in human immunodeficiency virus infected patients with perioperative adjuvant treatments].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 11-14-2014
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To observe the early wound healing of orthopedic surgery in human immunodeficiency virus (HIV) carrier patients treated with optimized auxiliary treatments.
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Lithium-Sulfur Batteries: Dendrite-Free Nanostructured Anode: Entrapment of Lithium in a 3D Fibrous Matrix for Ultra-Stable Lithium-Sulfur Batteries (Small 21/2014).
Small
PUBLISHED: 11-08-2014
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The entrapment of free-lithium in a 3D fibrous Li7 B6 framework produces a LiB nanostructured anode with a stable interface. This structure is demonstrated by Q. Zhang and co-workers on page 4257. The nanostructured anode not only reduces the areal current density that lowers the growth velocity of lithium deposits, but also limits the final size of the deposited lithium, which leads to a dendrite-free morphology at the macroscale.
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Global chemical composition of ambient fine particulate matter for exposure assessment.
Environ. Sci. Technol.
PUBLISHED: 11-06-2014
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Epidemiologic and health impact studies are inhibited by the paucity of global, long-term measurements of the chemical composition of fine particulate matter. We inferred PM2.5 chemical composition at 0.1° × 0.1° spatial resolution for 2004-2008 by combining aerosol optical depth retrieved from the MODIS and MISR satellite instruments, with coincident profile and composition information from the GEOS-Chem global chemical transport model. Evaluation of the satellite-model PM2.5 composition data set with North American in situ measurements indicated significant spatial agreement for secondary inorganic aerosol, particulate organic mass, black carbon, mineral dust, and sea salt. We found that global population-weighted PM2.5 concentrations were dominated by particulate organic mass (11.9 ± 7.3 ?g/m(3)), secondary inorganic aerosol (11.1 ± 5.0 ?g/m(3)), and mineral dust (11.1 ± 7.9 ?g/m(3)). Secondary inorganic PM2.5 concentrations exceeded 30 ?g/m(3) over East China. Sensitivity simulations suggested that population-weighted ambient PM2.5 from biofuel burning (11 ?g/m(3)) could be almost as large as from fossil fuel combustion sources (17 ?g/m(3)). These estimates offer information about global population exposure to the chemical components and sources of PM2.5.
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Lanreotide-conjugated PEG-DSPE micelles: an efficient nanocarrier targeting to somatostatin receptor positive tumors.
J Drug Target
PUBLISHED: 11-05-2014
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Abstract Lanreotide is an octapeptide analog of endogenous somatostatin, specifically binding with tumors over-express somatostatin receptor 2 (SSTR2). In this study, we conjugated lanreotide to 1, 2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy (poly-(ethylene glycol))-2000] (PEG-DSPE), constructed active targeted micelles (lanreotide-PM), characterized their in vitro and in vivo targeting effect, and explored the receptor mediated transportion. The uptake of lanreotide-PM was found to be related to the expression level of SSTR2 in different cell lines and the competitive inhibition phenomenon indicated that the cellular uptake of lanreotide-PM was via a receptor meditated mechanism. In vivo, more lanreotide-PM accumulated in SSTR2 high expression tumor xenografts, endocytosed by the tumor cells, induced more apoptosis of tumor cells, and suppressed tumor growth efficiently. In conclusion, lanreotide-modified micelles containing antitumor drugs provide a promising strategy for the treatment of SSTR-expressing tumors.
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Lithium-Sulfur Batteries: Hierarchical Vine-Tree-Like Carbon Nanotube Architectures: In-Situ CVD Self-Assembly and Their Use as Robust Scaffolds for Lithium-Sulfur Batteries (Adv. Mater. 41/2014).
Adv. Mater. Weinheim
PUBLISHED: 11-04-2014
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Hierarchical vine-tree-like carbon nanotube architectures composed of vine-like single-walled carbon nanotubes wrapping around the tree-like multi-walled carbon nanotubes are represented that are fabricated through in-situ chemical vapor deposition self-assembly, as reported by Q. Zhang, F. Wei, and co-workers on page 7051. Such biomimetic nanoarchitectures exhibit excellent performance when employed as the cathode scaffolds for lithium-sulfur batteries.
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Iodoacetic Acid activates nrf2-mediated antioxidant response in vitro and in vivo.
Environ. Sci. Technol.
PUBLISHED: 11-04-2014
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Iodoacetic acid (IAA) is an unregulated drinking-water disinfection byproduct with potent cytotoxicity, genotoxicity, and tumorigenicity in animals. Oxidative stress is thought to be essential for IAA toxicity, but the exact mechanism remains unknown. Here we evaluated the toxicity of IAA by examining nuclear factor E2-related factor 2 (Nrf2)-mediated antioxidant response, luciferase antioxidant response element (ARE) activity, and intracellular glutathione (GSH) in HepG2 cells. IAA showed significant activation of ARE-luciferase reporter, mRNA, and protein expression of Nrf2 and its downstream genes (GCLC, NQO1, and HO-1). IAA also increased the intracellular GSH level in HepG2 cells in a time- and concentration-dependent manner. Moreover, we verified IAA induced Nrf2-mediated antioxidant response in rats. Subsequently, we confirmed the specific role of Nrf2 in IAA induced toxicity using NRF2-knockdown cells. Deficiency of NRF2 significantly enhanced sensitivity to IAA toxicity and led to an increase of IAA induced micronulei. We also examined the effects of antioxidant on Nrf2-mediated response in IAA treated cells. Pretreatment with curcumin markedly reduced cytotoxicity and genotoxicity (micronuclei formation) IAA in HepG2 cells. Our work here provides direct evidence that IAA activates Nrf2-mediated antioxidant response in vitro and in vivo and that oxidative stress plays a role in IAA toxicity.
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Characterization of Cytochalasins from the Endophytic Xylaria sp. and Their Biological Functions.
J. Agric. Food Chem.
PUBLISHED: 11-03-2014
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Bioassay-guided fractionation of the fermentation extract of Xylaria sp. XC-16, an endophyte from Toona sinensis led to the isolation of two new cytochalasans cytochalasin Z27, 1, and cytochalasin Z28, 2, along with three known compounds seco-cytochalasin E, 3, and cytochalasin Z18, 4, and cytochalasin E, 5. The structures of 1 and 2 were elucidated by spectroscopic and electronic circular dichroism methods. Compound 5 was shown to be potently cytotoxic against brine shrimp (LC50 = 2.79 ?M), comparable to that of the positive agent toosendanin (LC50 = 4.03 ?M), and also exhibited potential phytotoxic effects on Lactuca sativa and Raphanus sativus L. seedlings, which are higher than that of the positive control glyphosate. Additionally, the fungicidal effect of 2 against the phytopathogen Gibberella saubinetti was better than that of hymexazol. This is the first report of the three types of cytochalasins present in genus Xylaria. A structure-phytotoxicity activity relationship is also discussed.
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Isolation and Characterization of Sesquiterpenes from Celastrus orbiculatus and Their Antifungal Activities against Phytopathogenic Fungi.
J. Agric. Food Chem.
PUBLISHED: 10-29-2014
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Celastrus orbiculatus is an insecticidal plant belonging to the Celastraceae family. In this survey on the secondary metabolites of plants for obtaining bioactive substances to serve agriculture, the chemical constituents of the fruits of C. orbiculatus were investigated. This phytochemical investigation resulted in the isolation of nine new and one known sesquiterpene. Their structures, especially the complicated stereochemical features, were elucidated on the basis of extensive NMR spectroscopic data analyses, time-dependent density functional theory CD calculations, and the CD exciton chirality method. Biological screenings disclosed that these sesquiterpenes showed antifungal activities against six phytopathogenic fungi. The results of our phytochemical investigation further disclosed the chemical components of C. orbiculatus, and biological screening implied that it may be potentially useful to protect crops against phytopathogenic fungi and the bioactive compounds may be regarded as candidate agents of antifungal agrochemicals for crop protection products.
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[Gene distribution characteristics of deletional ?-thalassemia in Guangxi region].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 10-24-2014
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To analyze the detection rate and gene distribution characteristic of deletional ?-thalassemia in Guangxi area, and to provide theoretic basis for thalassemia gene diagnosis and genetic counseling.
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Catalytic Self-Limited Assembly at Hard Templates: A Mesoscale Approach to Graphene Nanoshells for Lithium-Sulfur Batteries.
ACS Nano
PUBLISHED: 10-23-2014
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Hollow nanostructures afford intriguing structural features ranging from large surface area and fully exposed active sites to kinetically favorable mass transportation and tunable surface permeability. The unique properties and potential applications of graphene nanoshells with well-defined small cavities and delicately designed graphene shells are strongly considered. Herein, a mesoscale approach to fabricate graphene nanoshells with a single or few graphene layers and quite small diameters through a catalytic self-limited assembly of nanographene on in situ formed nanoparticles was proposed. The graphene nanoshells with a diameter of ca. 10-30 nm and a pore volume of 1.98 cm(3) g(-1) were employed as hosts to accommodate the sulfur for high-rate lithium-sulfur batteries. A very high initial discharge capacity of 1520 mAh g(-1), corresponding to 91% sulfur utilization rate at 0.1 C, was achieved on a graphene nanoshell/sulfur composite with 62 wt % loading. A very high retention of 70% was maintained when the current density increased from 0.1 C to 2.0 C, and an ultraslow decay rate of 0.06% per cycle during 1000 cycles was detected.
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[The study of stomatognathic muscles morphological changes after zygomatic plasty combined with mandibular angel plasty].
Zhonghua Zheng Xing Wai Ke Za Zhi
PUBLISHED: 10-18-2014
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To investigate the morphology change of stomatognathic muscles after zygomatic plasty combined with mandibular angel plasty.
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Resonance modes in stereometamaterial of square split ring resonators connected by sharing the gap.
Opt Express
PUBLISHED: 10-17-2014
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Stereometamaerials can fully utilize the 3D degrees of freedom to exploit the coupling and hybridization between multiple split ring resonators (SRRs), enabling more extraordinary resonances and properties over their planar counterparts. Here we propose and numerically study a kind of structure based on connected SRRs sharing their gap in a rotational fashion. It is shown that there are three typical resonance modes in such cage-like SRR (C-SRR) stereometamaterial in the communication and near infrared range. In the order of increasing energy, these modes can be essentially ascribed to magnetic torodial dipole, magnetic dipole, and a mixture of electric-dipole and magnetic toroidal dipole. We show that the latter two are derived from the second-order mode in the corresponding individual SRR, while the first one from the fundamental one. The highest energy mode remains relatively "dark" in an individual C-SRR due to the high-order feature and the rotational symmetry. However, they are all easily excitable in a C-SRR array, offering multiband filtering functionality.
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Novel Class 1 Integrons in Multi-drug Resistant Isolates from Eastern China.
Indian J. Microbiol.
PUBLISHED: 10-17-2014
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Integrons are mobile genetic elements able to capture, express and excise resistance genes, playing an important role in the spread of bacterial resistance. The present study was to investigate the occurrence and diversity of integrons in 120 clinical multi-drug resistant Gram-negative isolates from eastern China. Screening of integrons was performed by PCR and gene cassettes were further characterized by PCR-RFLP and sequencing. Class 1 integrons were detected in 70.8 % of isolates and no class 2 and class 3 integrons were detected in any isolates. A total of 19 resistant gene cassettes were identified, four representative of novel gene cassettes: an aacA3 variant (aacA3c), an aacA4 variant (aacA4'-17), a bla OXA variant (bla OXA-251 ), and a catB8 gene cassette interrupted by an insertion sequence IS10 (catB8::IS10). In addition, 14 cassette arrays were detected, including three novel integrons: gcuD1-aacA4'-17-gcu38B-catB8::IS10 (In712), aacA3c-aadA13-bla OXA-251 (In713) and dfrA1-gcu37-aadA5 (In714). The presence of novel integron structures in clinical isolates suggests hospital environments may favor the formation of novel combination of gene cassettes. Moreover, the high prevalence of integrons in multi-drug resistant isolates highlights the urgent need to employ effective means to avoid dissemination of drug-resistant bacteria.
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Bioactive Clerodane Diterpenoids from the Twigs of Casearia balansae.
J. Nat. Prod.
PUBLISHED: 10-06-2014
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Eight new clerodane diterpenes, balanspenes A-H (1-8), along with two known analogues (9 and 10), were isolated from the twigs of Casearia balansae. The structures of 1-8 were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analysis, and the absolute configurations of compounds 1, 4, and 7 were confirmed by comparing their experimental CD spectra with those calculated by the time-dependent density functional theory method. Compounds 4-7, 9, and 10 were found to possess the property of being able to stimulate NGF-mediated neurite outgrowth from PC12 cells.
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A perspective on point-of-care tests to detect eosinophilic bronchitis.
J Asthma
PUBLISHED: 10-02-2014
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Abstract Approximately 50% of asthma exacerbations and a third of COPD exacerbations are associated with an eosinophilic bronchitis. Quantitative cell counts reliably identify the number of eosinophils in sputum and treatment strategies that are guided by sputum eosinophil counts lead to significantly better outcomes than strategies guided by conventional assessments of symptoms and airflow. However, cell counts are not widely available and the results are not available in real time. Similarly, more sophisticated detection methods using immunoassays or genetic analysis via polymerase chain reaction are too costly and thus not amenable to rapid point-of-care diagnosis. Blood eosinophil counts and fraction of exhaled nitric oxide correlate poorly with airway eosinophilia, particularly in patients with severe airway diseases who are on corticosteroid therapy. Point of care assessments of eosinophil-specific activity may be provided by breathomics that employ metabolomics profiling of volatile compounds in breath. However, it is too early to decide if this would provide quantitative data to monitor therapy and disease activities longitudinally. Herein we provide a perspective on the potential for developing simple point-of-care tests with special emphasis on the potential for a bio-active paper diagnostic test to quantitatively assay the amount of eosinophil peroxidase in sputum samples by employing different types of detection systems.
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Seaurchin-like hierarchical NiCo2O4@NiMoO4 core-shell nanomaterials for high performance supercapacitors.
Phys Chem Chem Phys
PUBLISHED: 09-30-2014
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A novel electrode material of the three-dimensional (3D) multicomponent oxide NiCo2O4@NiMoO4 core-shell was synthesized via a facile two-step hydrothermal method using a post-annealing procedure. The uniform NiMoO4 nanosheets were grown on the seaurchin-like NiCo2O4 backbone to form a NiCo2O4@NiMoO4 core-shell material constructed by interconnected ultrathin nanosheets, so as to produce hierarchical mesopores with a large specific surface area of 100.3 m(2) g(-1). The porous feature and core-shell structure can facilitate the penetration of electrolytic ions and increases the number of electroactive sites. Hence, the NiCo2O4@NiMoO4 material exhibited a high specific capacitance of 2474 F g(-1) and 2080 F g(-1) at current densities of 1 A g(-1) and 20 A g(-1) respectively, suggesting that it has not only a very large specific capacitance, but also a good rate performance. In addition, the capacitance loss was only 5.0% after 1000 cycles of charge and discharge tests at the current density of 10 A g(-1), indicating high stability. The excellent electrochemical performance is mainly attributed to its 3D core-shell and hierarchical mesoporous structures which can provide unobstructed pathways for the fast diffusion and transportation of ions and electrons, a large number of active sites and good strain accommodation.
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p16 Protein Expression and Human Papillomavirus Status As Prognostic Biomarkers of Nonoropharyngeal Head and Neck Squamous Cell Carcinoma.
J. Clin. Oncol.
PUBLISHED: 09-29-2014
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Although p16 protein expression, a surrogate marker of oncogenic human papillomavirus (HPV) infection, is recognized as a prognostic marker in oropharyngeal squamous cell carcinoma (OPSCC), its prevalence and significance have not been well established in cancer of the oral cavity, hypopharynx, or larynx, collectively referred as non-OPSCC, where HPV infection is less common than in the oropharynx.
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Novel Free-Paclitaxel-Loaded Redox-Responsive Nanoparticles Based on a Disulfide-Linked Poly(ethylene glycol)-Drug Conjugate for Intracellular Drug Delivery: Synthesis, Characterization, and Antitumor Activity in Vitro and in Vivo.
Mol. Pharm.
PUBLISHED: 09-24-2014
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To address the obstacles facing cancer chemotherapeutics, including toxicity, side effects, water insolubility, and lack of tumor selectivity, a novel stimuli-responsive drug-delivery system was developed based on paclitaxel-loaded poly(ethylene glycol)-disulfide-paclitaxel conjugate nanoparticles (PEG-SS-PTX/PTX NPs). The formulation emphasizes several benefits, including polymer-drug conjugates/prodrugs, self-assembled NPs, high drug content, redox responsiveness, and programmed drug release. The PTX-loaded, self-assembled NPs, with a uniform size of 103 nm, characterized by DLS, TEM, XRD, DSC, and (1)H NMR, exhibited excellent drug-loading capacity (15.7%) and entrapment efficiency (93.3%). PEG-SS-PTX/PTX NPs were relatively stable under normal conditions but disassembled quickly under reductive conditions, as indicated by their triggered-aggregation phenomena and drug-release profile in the presence of dithiothreitol (DTT), a reducing agent. Additionally, by taking advantage of the difference in the drug-release rates between physically loaded and chemically conjugated drugs, a programmed drug-release phenomenon was observed, which was attributed to a higher concentration and longer action time of the drugs. The influence of PEG-SS-PTX/PTX NPs on in vitro cytotoxicity, cell cycle progression, and cellular apoptosis was determined in the MCF-7 cell line, and the NPs demonstrated a superior anti-proliferative activity associated with PTX-induced cell cycle arrest in G2/M phase and apoptosis compared to their nonresponsive counterparts. Moreover, the redox-responsive NPs were more efficacious than both free PTX and the non-redox-responsive formulation at equivalent doses of PTX in a breast cancer xenograft mouse model. This redox-responsive PTX drug delivery system is promising and can be explored for use in effective intracellular drug delivery.
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[Carcinoma ex pleomorphic adenoma occurring in the sublingual gland: a case report].
Hua Xi Kou Qiang Yi Xue Za Zhi
PUBLISHED: 09-23-2014
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Carcinoma ex pleomorphic adenoma occurring in the sublingual gland is extremely rare. In this report, a case of adenoid cystic carcinoma ex pleomorphic adenoma of the sublingual gland was presented.
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On-demand control of microfluidic flow via capillary-tuned solenoid microvalve suction.
Lab Chip
PUBLISHED: 09-18-2014
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A simple, low-cost and on-demand microfluidic flow controlling platform was developed based on a unique capillary-tuned solenoid microvalve suction effect without any outer pressure source. The suction effect was innovatively employed as a stable and controllable driving force for the manipulation of the microfluidic system by connecting a piece of capillary between the microvalve and the microfluidic chip, which caused significant hydrodynamic resistance differences among the solenoid valve ports and changed the flowing mode inside the valve. The volume of sucked liquid could be controlled from microliters even down to picoliters either by decreasing the valve energized duration (from a maximum energized duration to the valve response time of 20 ms) or by increasing the inserted capillary length (i.e., its hydrodynamic resistance). Several important microfluidic unit operations such as cell/droplet sorting and on-demand size-controllable droplet generation have been demonstrated on the developed platform and both simulations and experiments confirmed that this platform has good controllability and stability.
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[Stabilized thiomer PAA-Cys-6MNA].
Yao Xue Xue Bao
PUBLISHED: 09-13-2014
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The aimed of this study was to prepare stabilized thiomers to overcome the poor stability character of traditional thiomers. Poly(acrylic acid)-cysteine (PAA-Cys) was synthesized by conjugating cysteine with poly(acrylic acid) and poly(acrylic acid)-cysteine-6-mercaptonicotinic acid (PAA-Cys-6MNA, stabilized thiomers) was synthesized by grafting a protecting group 6-mercaptonicotinic acid (6MNA) with PAA-Cys. The free thiol of PAA-Cys was determined by Ellmann's reagent method and the ratio of 6MNA coupled was determined by glutathione reduction method. The study of permeation enhancement and stabilized function was conducted by using Franz diffusion cell method, with fluorescein isothiocyanate dextran (FD4) used as model drug. The influence of polymers on tight junctions of Caco-2 cell monolayer was detected with laser scanning confocal fluorescence microscope. The results indicated that both PAA-Cys and PAA-Cys-6MNA could promote the permeation of FD4 across excised rat intestine, and the permeation function of PAA-Cys-6MNA was not influence by the pH of the storage environment and the oxidation of air after the protecting group 6MNA was grafted. The distribution of tight junction protein of Caco-2 cell monolayer F-actin was influenced after incubation with PAA-Cys and PAA-Cys-6MNA. In conclusion, stabilized thiomers (PAA-Cys-6MNA) maintained the permeation function compared with the traditional thiomers (PAA-Cys) and its stability was improved. The mechanism of the permeation enhancement function of the polymers might be related to their influence on tight junction relating proteins of cells.
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Characterization and NO inhibitory activities of chemical constituents from an edible plant Petasites tatewakianus.
J. Agric. Food Chem.
PUBLISHED: 09-12-2014
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Petasites tatewakianus is an edible plant belonging to the family Compositae. In our continuous search for NO inhibitors, which may be useful for the development of anti-inflammatory agents, the chemical constituents of the leaves of the edible plant P. tatewakianus were investigated. This phytochemical investigation led to the isolation of 3 new (1-3) and 10 known (4-13) sesquiterpenes and 2 other types of known compounds (14 and 15). Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analyses, and the absolute configurations of compounds 1 and 3 were confirmed by comparing their experimental CD spectra with those calculated by the time-dependent density functional theory (TDDFT) method. The following biological studies disclosed that these isolated compounds showed inhibitory activities on LPS-induced NO production in murine microglial BV-2 cells. The results of our phytochemical investigation, including two new bakkenolide sesquiterpenes (1 and 2), one new sesquiterpene with an unusual carbon skeleton (3), and the first report of compounds 5-7 and 10-15 from this species, further revealed the chemical composition of P. tatewakianus as an edible plant, and the biological studies implied that P. tatewakianus, containing bioactive substances with the inhibitory activities of NO production, was potentially beneficial to human health.
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Periprostatic adiposity measured on magnetic resonance imaging correlates with prostate cancer aggressiveness.
Urol J
PUBLISHED: 09-06-2014
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To evaluate the correlation between aggressiveness of prostate cancer (PCa) and obesity measur­ing the periprostatic fat on magnetic resonance imaging (MRI).
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The synthesis of 5-alkyl[3,4-c]thienopyrrole-4,6-dione-based polymers using a Pd-catalyzed oxidative C-H/C-H homopolymerization reaction.
Chem. Commun. (Camb.)
PUBLISHED: 09-06-2014
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A new, simple, mild, atom economical homopolymerization method through Pd-catalyzed oxidative C-H/C-H coupling was developed for the preparation of a series of 5-alkyl[3,4-c]thienopyrrole-4,6-dione-based conjugated polymers.
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Advances and Patents about Grinding Equipments with Nano-Particle Jet Minimum Quantity Lubrication.
Recent Pat Nanotechnol
PUBLISHED: 09-05-2014
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In recent years, a large number of patents have been devoted to developing minimum quantity lubrication (MQL) grinding techniques that can significantly improve both environmentally conscious and energy saving and costeffective sustainable grinding fluid alternatives. Among them, one patent is about a controllable nano-fluids jet MQL grinding system based on electrostatic atomization. Using the principle of electrostatics, it can achieve the control of droplet transfer by charging the sprayed droplets. This system can improve the uniformity of the droplet spectrum, liquid deposition efficiency and effective utilization of liquid. It can also effectively control the movement patterns of the droplets, thereby reducing the pollution of the environment and providing better health protection for workers. Although researchers accomplished profound and systematic studies on MQL, especially on nano-particles jet MQL. It can solve the shortage of MQL in cooling performance, greatly improve the working environment, save energy and reduce costs to achieve a low-carbon manufacturing. The unique lubricating performance and tribological property of solid nano-particles form nano-particle shearing films at the grinding wheel/workpiece interface, which can enhance the lubricating performance of MQL grinding. Existing studies on MQL grinding equipments, however, cannot meet the needs of the technological development. Therefore, our research provided a general introduction of the latest patients and research progress of nanoparticles jet MQL grinding equipments presented by the research team from Qingdao Technological University.
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miR?886?3p upregulation in clear cell renal cell carcinoma regulates cell migration, proliferation and apoptosis by targeting PITX1.
Int. J. Mol. Med.
PUBLISHED: 09-04-2014
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miR?886?3p has been discovered to be involved in the oncogenesis, progression and metastasis of several types of human cancer. The aim of the present study was to identify the biological function of miR?886?3p in clear cell renal cell carcinoma (ccRCC) and to determine its possible molecular mechanisms. miR?886?3p was found to be significantly upregulated in ccRCC tissues (P<0.05), in accordance with a previous sequencing result. Functional experiments revealed that forced downregulation of miR?886?3p significantly inhibited cellular migration, suppressed cell proliferation and induced cell apoptosis of renal cancer cells. Paired?like homeodomain 1 (PITX1), which has been identified as a tumor suppressor, was found to be downregulated in ccRCC tissues and identified as a target gene of miR?886?3p. Further experiments demonstrated that the protein level, and not the mRNA level, of PITX1 was significantly decreased or increased when miR?886?3p was upregulated or downregulated, respectively, indicating that miR?886?3p acted as an oncogene by directly regulating the protein expression of PITX1 at a post?transcriptional level. In conclusion, this study revealed that miR?886?3p was upregulated in ccRCC and was involved in cellular migration, proliferation and apoptosis of renal cancer cells by directly targeting the tumor suppressor gene, PITX1.
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Identification of a novel polyprenylated acylphloroglucinol?derived SIRT1 inhibitor with cancer?specific anti-proliferative and invasion-suppressing activities.
Int. J. Oncol.
PUBLISHED: 09-03-2014
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SIRT1, a class III histone deacetylase, plays a critical role in regulating cancer cell growth, migration and invasion, which makes it a potential target for cancer therapeutics. In this study, we screened derivatives of several groups of natural products and identified a novel SIRT1 inhibitor JQ-101, a synthetic derivative of the polyprenylated acylphloroglucinol (PPAP) natural products, with an IC(50) for SIRT1 of 30 µM in vitro, with 5-fold higher activity for SIRT1 vs. SIRT2. Exposure of tumor cells to JQ-101 significantly enhanced acetylation of p53 and histone H4K16 at known sites of SIRT1 deacetylation, validating SIRT1 as its cellular target. JQ-101 suppressed cancer cell growth and survival by targeting SIRT1, and also exhibited selective cytotoxicity towards a panel of human tumor cell lines, while producing no toxicity in two normal human cell types at comparable concentrations. JQ-101 induced both apoptosis and cell senescence, and suppressed cancer cell invasion in vitro. In summary, we have identified JQ-101 as a new SIRT1 inhibitor which may have potential application in cancer treatment through its ability to induce tumor cell apoptosis and senescence and suppress cancer cell invasion.
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Producing more grain with lower environmental costs.
Nature
PUBLISHED: 09-03-2014
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Agriculture faces great challenges to ensure global food security by increasing yields while reducing environmental costs. Here we address this challenge by conducting a total of 153 site-year field experiments covering the main agro-ecological areas for rice, wheat and maize production in China. A set of integrated soil-crop system management practices based on a modern understanding of crop ecophysiology and soil biogeochemistry increases average yields for rice, wheat and maize from 7.2 million grams per hectare (Mg ha(-1)), 7.2 Mg ha(-1) and 10.5 Mg ha(-1) to 8.5 Mg ha(-1), 8.9 Mg ha(-1) and 14.2 Mg ha(-1), respectively, without any increase in nitrogen fertilizer. Model simulation and life-cycle assessment show that reactive nitrogen losses and greenhouse gas emissions are reduced substantially by integrated soil-crop system management. If farmers in China could achieve average grain yields equivalent to 80% of this treatment by 2030, over the same planting area as in 2012, total production of rice, wheat and maize in China would be more than enough to meet the demand for direct human consumption and a substantially increased demand for animal feed, while decreasing the environmental costs of intensive agriculture.
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Controlled functionalization of carbonaceous fibers for asymmetric solid-state micro-supercapacitors with high volumetric energy density.
Adv. Mater. Weinheim
PUBLISHED: 09-02-2014
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A 1.8 V asymmetric solid-state flexible micro-supercapacitor is designed with one MnO2 -coated reduced graphene oxide/single-walled carbon nanotube (rGO/SWCNT) composite fiber as positive electrode and one nitrogen-doped rGO/SWCNT fiber as negative electrode, which demonstrates ultrahigh volumetric energy density, comparable to some thin-film lithium batteries, along with high power density, long cycle life, and good flexibility.
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Low effective mass and carrier concentration optimization for high performance p-type Mg2(1-x)Li2xSi0.3Sn0.7 solid solutions.
Phys Chem Chem Phys
PUBLISHED: 09-02-2014
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Mg2Si1-xSnx solid solutions are promising thermoelectric materials for power generation applications in the 500-800 K range. Outstanding n-type forms of these solid solutions have been developed in the past few years with the thermoelectric figure of merit ZT as high as 1.4. Unfortunately, no comparable performance has been achieved so far with p-type forms of the structure. In this work, we use Li doping on Mg sites in an attempt to enhance and control the concentration of hole carriers. We show that Li as well as Ga is a far more effective p-type dopant in comparison to Na or K. With the increasing content of Li, the electrical conductivity rises rapidly on account of a significantly enhanced density of holes. While the Seebeck coefficient decreases concomitantly, the power factor retains robust values supported by a rather high mobility of holes. Theoretical calculations indicate that Mg2Si0.3Sn0.7 intrinsically possesses the almost convergent double valence band structure (the light and heavy band), and Li doping retains a low density of states (DOS) on the top of the valence band, contrary to the Ga doping at the sites of Si/Sn. Low temperature specific heat capacity studies attest to a low DOS effective mass in Li-doped samples and consequently their larger hole mobility. The overall effect is a large power factor of Li-doped solid solutions. Although the thermal conductivity increases as more Li is incorporated in the structure, the enhanced carrier density effectively shifts the onset of intrinsic excitations (bipolar effect) to higher temperatures, and the beneficial role of phonon Umklapp processes as the primary limiting factor to the lattice thermal conductivity is thus extended. The final outcome is the figure of merit ZT ? 0.5 at 750 K for x = 0.07. This represents a 30% improvement in the figure of merit of p-type Mg2Si1-xSnx solid solutions over the literature values. Hence, designing low DOS near Fermi level EF for given carrier pockets can serve as an effective approach to optimize the PF and thus ZT value.
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Hierarchical Vine-Tree-Like Carbon Nanotube Architectures: In-Situ CVD Self-Assembly and Their Use as Robust Scaffolds for Lithium-Sulfur Batteries.
Adv. Mater. Weinheim
PUBLISHED: 09-01-2014
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Hierarchical vine-tree-like carbon nanotube architectures composed of vine-like single-walled carbon nanotubes wrapping around the tree-like multi-walled carbon nanotubes are fabricated through in-situ chemical vapor deposition self-assembly. The vine-tree-like nanoarchitectures exhibit excellent cycling stability and rate performance when employed as the cathode scaffolds for lithium-sulfur batteries.
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miR-124 inhibits growth and invasion of gastric cancer by targeting ROCK1.
Asian Pac. J. Cancer Prev.
PUBLISHED: 08-30-2014
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MicroRNAs (miRNAs) act as critical regulators of genes involved in many biological processes. Aberrant alteration of miRNAs have been found in many cancers, including gastric cancer (GC), but the molecular mechanisms are not well understood. Herein, we investigated the role of miR-124 in GC. We found that its expression was significantly reduced in both GC tissue samples and cell lines. Forced expression of miR-124 suppressed GC cell proliferation, migration, and invasion. Furthermore, the Rho-associated protein kinase (ROCK1) was identified as a direct target of miR-124 in GC cells. Finally, silencing of ROCK1 showed similar effects as miR-124 overexpression, while supplementation of ROCK1 remarkably restored the cell growth and invasion inhibited by miR-124. Together, our data demonstrate that miR-124 acts as a tumor suppressor by targeting ROCK1, and posit miR-124 as a novel strategy for GC treatment.
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Bioavailability of tramadol hydrochloride after administration via different routes in rats.
Biopharm Drug Dispos
PUBLISHED: 08-29-2014
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Tramadol is a synthetic non-opiate analgesic drug and effective for many kinds of chronic and acute pain. This study compared the bioavailability of tramadol after different administration routes in rats (oral, buccal and nasal). A simple HPLC analytical approach was used to determine the concentration of tramadol in plasma. The pharmacokinetic behavior and bioavailability of tramadol after administration via different routes in rats were investigated. Nasal and buccal administration of tramadol resulted in a fast increase followed by a rapid decrease in the plasma tramadol concentration. The Cmax values following buccal and nasal administration were 6 times and 20 times higher than that of oral administration, respectively, (6827.85?±?7970.87?ng/ml, 22191.84?±?5364.86?ng/ml, vs 1127.03?±?778.34?ng/ml). The relative bioavailabilities of the nasal- and buccal-administered drug when compared with the oral route were 504.8% and 183.4%, respectively, which is much higher than that of oral administration. Nasal and buccal administration increased the bioavailability of tramadol, which may allow for a reduction in the dose of tramadol and a subsequent decrease in both side effects and toxicity. Therefore, this approach provides an effective choice for the delivery of tramadol, an analgesic drug. Copyright © 2014 John Wiley & Sons, Ltd.
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Gene expression profiles on predicting protein interaction network and exploring of new treatments for lung cancer.
Mol. Biol. Rep.
PUBLISHED: 08-28-2014
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In the present study, we aimed to explore disease-associated genes and their functions in lung cancer. We downloaded the gene expression profile GSE4115 from Gene Expression Omnibus (GEO) database. Total 97 lung cancer and 90 adjacent non-tumor lung tissue (normal) samples were applied to identify the differentially expressed genes (DEGs) by paired t test and variance analysis in spectral angle mapper (SAM) package in R. Gene Ontology (GO) functional enrichment analysis of DEGs were performed with Database for Annotation Visualization and Integrated Discovery, followed by construction of protein-protein interaction (PPI) network from Human Protein Reference Database (HPRD). Finally, network modules were analyzed by the MCODE algorithm to detect protein complexes in the PPI network. Total 3,102 genes were identified as DEGs at FDR < 0.05, including 1,146 down-regulated and 1,956 up-regulated DEGs. GO functional enrichment analysis revealed that up-regulated DEGs mainly participated in cell cycle and intracellular related functions, and down-regulated DEGs might influence cell functions. There were 39,240 pairs of PPIs in human obtained from HPRD databases, 3,102 DEGs were mapped to this PPI network, in which 2,429 pairs of PPIs and 1,342 genes were identified. With MCODE algorithm, 48 modules were selected, including five corresponding modules and three modules with differences in gene expressing profiles. In addition, three DGEs, FXR2, ARFGAP1 and ELAVL1 were discovered as potential lung cancer related genes. The discovery of featured genes which were probably related to lung cancer, has a great significance on studying mechanism, distinguishing normal and cancer tissues, and exploring new treatments for lung cancer.
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Novel daidzein analogs enhance osteogenic activity of bone marrow-derived mesenchymal stem cells and adipose-derived stromal/stem cells through estrogen receptor dependent and independent mechanisms.
Stem Cell Res Ther
PUBLISHED: 08-28-2014
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Osteoporosis is a disease characterized by low bone mineral density (BMD) and increased risk of fractures. Studies have demonstrated the use of phytoestrogens, or plant-derived estrogens, such as genistein and daidzein, to effectively increase osteogenic activity of bone marrow-derived mesenchymal stem cells (BMSCs). Herein, the effects of daidzein analogs on the osteogenic differentiation efficiency of human BMSC and adipose-derived stromal/stem cells (ASC) were explored.
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[Genotypes of 1 571 cases of Hb H disease in Guangxi area].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 08-26-2014
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To analyze the status and genotypes of Hb H disease in GuangXi area.
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Randomized Phase III Trial of Concurrent Accelerated Radiation Plus Cisplatin With or Without Cetuximab for Stage III to IV Head and Neck Carcinoma: RTOG 0522.
J. Clin. Oncol.
PUBLISHED: 08-25-2014
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Combining cisplatin or cetuximab with radiation improves overall survival (OS) of patients with stage III or IV head and neck carcinoma (HNC). Cetuximab plus platinum regimens also increase OS in metastatic HNC. The Radiation Therapy Oncology Group launched a phase III trial to test the hypothesis that adding cetuximab to the radiation-cisplatin platform improves progression-free survival (PFS).
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Cold exposure inhibits hypothalamic Kiss-1 gene expression, serum leptin concentration, and delays reproductive development in male Brandt's vole (Lasiopodomys brandtii).
Int J Biometeorol
PUBLISHED: 08-22-2014
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Cold commonly affects growth and reproductive development in small mammals. Here, we test the hypothesis that low ambient temperature will affect growth and puberty onset, associated with altered hypothalamic Kiss-1 gene expression and serum leptin concentration in wild rodents. Male Brandt's voles (Lasiopodomys brandtii) were exposed to cold (4?±?1 °C) and warm (23?±?1 °C) conditions from the birth and sacrificed on different developmental stages (day 26, day 40, day 60, and day 90, respectively). Brandt's voles increased the thermogenic capacity of brown adipose tissue, mobilized body fat, decreased serum leptin levels, and delayed the reproductive development especially on day 40 in the cold condition. They increased food intake to compensate for the high energy demands in the cold. The hypothalamic Kiss-1 gene expression on day 26 was decreased, associated with lower wet testis mass and testis testosterone concentration on day 40, in the cold-exposed voles compared to that in the warm. Serum leptin was positively correlated with body fat, testis mass, and testosterone concentration. These data suggested that cold exposure inhibited hypothalamic Kiss-1 gene expression during the early stage of development, decreased serum leptin concentration, and delayed reproductive development in male Brandt's voles.
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Identification and characterisation a surface-associated arginine peptidase in Streptococcus suis serotype 2.
Microbiol. Res.
PUBLISHED: 08-18-2014
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Streptococcus suis is an important zoonotic pathogen worldwide and is responsible for disease in swine and humans. In the present study, we identified and characterised a surface-associated peptidase (abpb, amylase-binding protein B) in Streptococcus suis serotype 2 (S. suis 2) that has high hydrolytic activity towards H-Arg-pNa, with maximum activity at pH 7.0. Stimulation of RAW 264.7 macrophages with purified recombinant abpb protein triggered the release of pro-inflammatory cytokines. An abpb-deficient mutant ?Abpb was constructed by homologous recombination to determine the role of abpb in S. suis 2. The mutant ?Abpb showed decreased adherence to Hep-2 cells and attenuated virulence in a mouse model compared to the wild type strains. The results of the infection showed impaired bacterial growth in vivo and poor colonisation of the organs. In a protection assay, the recombinant abpb provided excellent protection against a lethal challenge of S. suis 2. Together, these findings suggest that abpb contributes to the pathogenicity of S. suis 2 and may be another target for S. suis prevention and control.
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Functional profile of a novel modulator of serotonin, dopamine, and glutamate neurotransmission.
Psychopharmacology (Berl.)
PUBLISHED: 08-15-2014
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Schizophrenia remains among the most prevalent neuropsychiatric disorders, and current treatment options are accompanied by unwanted side effects. New treatments that better address core features of the disease with minimal side effects are needed.
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A prospective study of biomarker-guided chemotherapy in patients with non-small cell lung cancer.
Cancer Chemother. Pharmacol.
PUBLISHED: 08-14-2014
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To assess the therapeutic value of biomarker-guided chemotherapy in patients with advanced non-small cell lung cancer (NSCLC).
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Pyrolysis characteristics and kinetic analysis of different dewatered sludge.
Bioresour. Technol.
PUBLISHED: 08-12-2014
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Pyrolysis behavior and kinetic properties of four different sludge, including raw sludge and three sludge respectively dewatered with FeCl3/CaO, FeCl3/CaO/coal and Fenton's reagent (Fe(2+)+H2O2)/CaO, were analyzed by using thermogravimetry coupled with Fourier transform infrared spectrometry (TG-FTIR). The results show that organics of raw sludge mainly decomposed at 378-676K, and the decomposition temperature of conditioned sludge was prolonged to 823K. Addition of coal and catalysis of CaO/ferric salt both promoted sludge pyrolysis, leading to more NH3, CH4 and CO productions. Compared with dry sludge, wet sludge pyrolysis was hard to finish completely, and the first peak of organics' decomposition appeared at higher temperature (about 573K). Additionally, the global reaction model was suited to determine kinetic parameters, which showed that dry sludge conditioned with more CaO addition had higher E values than those of dry raw sludge. Opposite results were obtained when sludge samples were wet.
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Molecular Signaling Network Motifs Provide a Mechanistic Basis for Cellular Threshold Responses.
Environ. Health Perspect.
PUBLISHED: 08-12-2014
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Background: Increasingly, there is a move toward using in vitro toxicity testing for assessment of human health risk by chemicals. As with in vivo toxicity testing, an important question for in vitro results is whether there are thresholds for adverse cellular responses. Empirical evaluations may show consistency with thresholds, but the main evidence has to come from mechanistic considerations. Objectives: Cellular response behaviors depend on the molecular pathway and circuitry in the cell and the manner in which chemicals perturb these circuits. Understanding circuit structures that are inherently capable of resisting small perturbations and producing threshold responses is an important step towards mechanistically interpreting in vitro testing data. Methods: Here we have examined dose-response characteristics for several biochemical network motifs. These network motifs are basic building blocks of molecular circuits underpinning a variety of cellular functions, including adaptation, homeostasis, proliferation, differentiation, and apoptosis. For each motif, we present biological examples and models to illustrate how thresholds arise from specific network structures. Discussion and Conclusion: Integral feedback, feedforward and transcritical bifurcation motifs can generate thresholds. Other motifs, e.g., proportional feedback and ultrasensitivity, produce responses where the slope in the low-dose region is small and stays close to the baseline. Feedforward control may lead to nonmonotonic or hormetic responses. We conclude that network motifs provide a basis for understanding thresholds for cellular responses. Computational pathway modeling of these motifs and their combinations occurring in molecular signaling networks will be a key element in new risk assessment approaches based on in vitro cellular assays.
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A Chinese herbal Formula, Chang-Wei-Qin, Synergistically Enhances Antitumor Effect of Oxaliplatin.
Pathol. Oncol. Res.
PUBLISHED: 08-08-2014
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Chang-Wei-Qing (CWQ), a Chinese herbal formula, has long been employed clinically to treat cancers. In this study, we investigated the synergistic effect of CWQ with oxaliplatin (OXA) on the tumor growth inhibition of orthotopic transplanted colon cancer and explored the underlying mechanism. By generating the orthotopic transplanted nude mouse model of human colon carcinoma, we found that (1) CWQ enhanced OXA-mediated tumor suppression by 4.25-fold. (2) The body weights of nude mice in CWQ group and combination group were increased. (3) The survival time of tumor-bearing nude mice was dramatically improved in CWQ and CWQ/OXA group. (4) CWQ could restore OXA-mediated deregulation of copper transporter genes, hCTR1, ATP7A and ATP7B. (5) OXA-induced drug resistance index for OXA, 5-FU, HCPT and THP were 7.59, 4.28, 5.78 and 4.50 respectively, while the reversal index by combined CWQ treatment were 6.57, 2.61, 4.97 and 3.10, respectively. Our study demonstrates that the repeated intraperitoneal injection of OXA can induce multi-drug resistance of orthotopic transplanted nude mouse model of human colon carcinoma. The CWQ treatment can alleviate OXA-triggered side effects and reverse platinum drug resistance via up-regulation of hCTR1 expression and down-regulation of ATP7A and ATP7B levels.
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Antimicrobial and allelopathic metabolites produced by Penicillium brasilianum.
Nat. Prod. Res.
PUBLISHED: 08-07-2014
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Six known compounds, isoroquefortine C (1), griseofulvin (2), ergosterol peroxide (3), 3?-hydroxy-(22E,24R)-ergosta-5,8,22-trien-7-one (4), cerevisterol (5) and (22E,24R)-6?-methoxyergosta-7,22-diene-3?,5?-diol (6), were produced by the fungus Penicillium brasilianum, and their structures were elucidated by spectroscopic methods. This is the first report on isoroquefortine C as naturally occurring compound. Their bioactivities against five phytopathogenic fungi (Gibeberalla saubinetti, Fusarium solani, Botrytis cinerea, Colletotrichum gloeosporioides and Alternaria solani) and four pathogenic bacteria (Escherichia coli, Bacillus subtilis, Staphyloccocus aureus and Bacillus cereus), as well as allelopathic activities on Raphanus sativus were tested. Compound 1 exhibited a remarkable antifungal activity with minimum inhibitory concentration (MIC) of 12.5 ?M against C. gloeosporioides, in comparison with positive control hymexazol (MIC 25 ?M). Compound 2 displayed strong inhibitory effects on the growth of A. solani and S. aureus with MIC of 3.13 ?M for each. Compounds 2 and 3 displayed a significant growth-inhibition activity on R. sativus.
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Investigation of 3-D ordered materials with a high adsorption capacity for BSA and their potential application as an oral vaccine adjuvant.
J Colloid Interface Sci
PUBLISHED: 08-01-2014
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3-D ordered macroporous (3DOM) materials were customized for BSA adsorption and further oral immunization. These carriers have a high adsorption capacity and our customized carrier showed a distinctive double-plateau adsorption behavior. Different BSA release rates (between the two plateaus) could be obtained by adjusting the ratio of the protein adsorbed on the internal surface and the external surface. This suggests that the release pattern was determined by the adsorption state. One benefit is that the same carrier could have different release profiles making it possible to study the relationship between the release behavior and adjuvant effects without any distractions. Compared with free BSA alone, a significantly higher level of serum IgG, IgA induced by BSA/3DOM was observed and the release profile had an effect on the immunity. The IgG1 and IgG2a titers suggesting that both the Th1 and Th2 mediated immune response were induced. Therefore, this research could help in the development of a novel inorganic oral adjuvant and provide a new avenue for the administration of oral vaccine.
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Improved hybrid optimization algorithm for 3D protein structure prediction.
J Mol Model
PUBLISHED: 07-30-2014
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A new improved hybrid optimization algorithm - PGATS algorithm, which is based on toy off-lattice model, is presented for dealing with three-dimensional protein structure prediction problems. The algorithm combines the particle swarm optimization (PSO), genetic algorithm (GA), and tabu search (TS) algorithms. Otherwise, we also take some different improved strategies. The factor of stochastic disturbance is joined in the particle swarm optimization to improve the search ability; the operations of crossover and mutation that are in the genetic algorithm are changed to a kind of random liner method; at last tabu search algorithm is improved by appending a mutation operator. Through the combination of a variety of strategies and algorithms, the protein structure prediction (PSP) in a 3D off-lattice model is achieved. The PSP problem is an NP-hard problem, but the problem can be attributed to a global optimization problem of multi-extremum and multi-parameters. This is the theoretical principle of the hybrid optimization algorithm that is proposed in this paper. The algorithm combines local search and global search, which overcomes the shortcoming of a single algorithm, giving full play to the advantage of each algorithm. In the current universal standard sequences, Fibonacci sequences and real protein sequences are certified. Experiments show that the proposed new method outperforms single algorithms on the accuracy of calculating the protein sequence energy value, which is proved to be an effective way to predict the structure of proteins.
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Effects of meteorology and secondary particle formation on visibility during heavy haze events in Beijing, China.
Sci. Total Environ.
PUBLISHED: 07-25-2014
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The causes of haze formation in Beijing, China were analyzed based on a comprehensive measurement, including PBL (planetary boundary layer), aerosol composition and concentrations, and several important meteorological parameters such as visibility, RH (relative humidity), and wind speed/direction. The measurement was conducted in an urban location from Nov. 16, 2012 to Jan. 15, 2013. During the period, the visibility varied from >20km to less than a kilometer, with a minimum visibility of 667m, causing 16 haze occurrences. During the haze occurrences, the wind speeds were less than 1m/s, and the concentrations of PM2.5 (particle matter with radius less than 2.5?m) were often exceeded 200?g/m(3). The correlation between PM2.5 concentration and visibility under different RH values shows that visibility was exponentially decreased with the increase of PM2.5 concentrations when RH was less than 80%. However, when RH was higher than 80%, the relationship was no longer to follow the exponentially decreasing trend, and the visibility maintained in very low values, even with low PM2.5 concentrations. Under this condition, the hygroscopic growth of particles played important roles, and a large amount of water vapor acted as particle matter (PM) for the reduction of visibility. The variations of meteorological parameters (RH, PBL heights, and WS (wind speed)), chemical species in gas-phase (CO, O3, SO2, and NOx), and gas-phase to particle-phase conversions under different visibility ranges were analyzed. The results show that from high visibility (>20km) to low visibility (<2km), the averaged PBL decreased from 1.24km to 0.53km; wind speeds reduced from 1m/s to 0.5m/s; and CO increased from 0.5ppmv to 4.0ppmv, suggesting that weaker transport/diffusion caused the haze occurrences. This study also found that the formation of SPM (secondary particle matter) was accelerated in the haze events. The conversions between SO2 and SO4 as well as NOx to NO3(-) increased, especially under high humidity conditions. When the averaged RH was 70%, the conversions between SO2 and SO4 accounted for about 20% concentration of PM2.5, indicating that formation of secondary particle matter had important contribution for the haze occurrences in Beijing.
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Experimental study on the optimization of general conditions for a free-flow electrophoresis device with a thermoelectric cooler†
J Sep Sci
PUBLISHED: 07-18-2014
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With a given free-flow electrophoresis device, reasonable conditions (electric field strength, carrier buffer conductivity, and flow rate) are crucial for an optimized separation. However, there has been no experimental study on how to choose reasonable general conditions for a free-flow electrophoresis device with a thermoelectric cooler in view of Joule heat generation. Herein, comparative experiments were carried out to propose the selection procedure of general conditions in this study. The experimental results demonstrated that appropriate conditions were (i) <67 V/cm electric field strength; (ii) lower than 1.3 mS/cm carrier buffer conductivity (Tris-HCl: 20 mM Tris was titrated by HCl to pH 8.0); and (iii) higher than 3.6 mL/min carrier buffer flow rate. Furthermore, under inappropriate conditions (e.g. 400 V voltage and 40 mM Tris-HCl carrier buffer), the free-flow electrophoresis separation would be destroyed by bubbles caused by more Joule heating. Additionally, a series of applications under the appropriate conditions were performed with samples of model dyes, proteins (bovine serum albumin, myoglobin, and cytochrome c), and cells (Escherichia coli, Streptococcus thermophilus, and Saccharomyces cerevisiae). The separation results showed that under the appropriate conditions, separation efficiency was obviously better than that in the previous experiments with randomly or empirically selected conditions.
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Combined effects of Fenton peroxidation and CaO conditioning on sewage sludge thermal drying.
Chemosphere
PUBLISHED: 06-27-2014
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Joint application of Fenton's reagent and CaO can dramatically enhance sludge dewaterability, thus are also likely to affect subsequent thermal drying process. This study investigated the synergistic effects of the two conditioners on the thermal drying behavior of sewage sludge and the emission characteristics of main sulfur-/nitrogen-containing gases. According to the results, Fenton peroxidation combined with CaO conditioning efficiently promoted sludge heat transfer, reduced the amounts of both free and bound water, and created porous structure in solids to provide evaporation channels, thus producing significant positive effects on sludge drying performance. In this case, the required time for drying was shortened to one-third. Additionally, joint usage of Fenton's reagent and CaO did not increase the losses of organic matter during sludge drying process. Meanwhile, they facilitated the formation of sulfate and sulfonic acid/sulfone, leading to sulfur retention in dried sludge. Both of Fenton peroxidation and CaO conditioning promoted the oxidation, decomposition, and/or dissolution of protein and inorganic nitrogen in sludge pre-treatment. As a consequence, the emissions of sulfurous and nitrogenous gases from dewatered sludge drying were greatly suppressed. These indicate that combining Fenton peroxidation with CaO conditioning is a promising strategy to improve drying efficiency of sewage sludge and to control sulfur and nitrogen contaminants during sludge thermal drying process.
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Dendrite-Free Nanostructured Anode: Entrapment of Lithium in a 3D Fibrous Matrix for Ultra-Stable Lithium-Sulfur Batteries.
Small
PUBLISHED: 06-23-2014
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Entrapment of free lithium in a 3D fibrous Li7 B6 framework allows LiB nanostructured anodes with stable interfaces between the electrolyte and the electrode, which retards the formation of lithium dendrites. A lithium-sulfur cell with a nanostructured anode is created with a high Coulombic efficiency and high capacity retention rate of 36.3% after 2000 cycles.
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Ultra-early versus delayed coil treatment for ruptured poor-grade aneurysm.
Neuroradiology
PUBLISHED: 06-19-2014
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The timing of definitive aneurysm treatment (coiling or clipping) in poor-grade (Hunt-Hess IV or V) subarachnoid haemorrhage (SAH) patients has been a controversial topic. The purpose of this retrospective study was to analyse whether ultra-early coiling of ruptured intracranial aneurysms improves the clinical outcomes of poor-grade SAH patients.
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Medicinal properties of Hericium erinaceus and its potential to formulate novel mushroom-based pharmaceuticals.
Appl. Microbiol. Biotechnol.
PUBLISHED: 06-12-2014
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Hericium erinaceus is an important mushroom with edible values and medicinal properties. Both the mycelium and the fruiting bodies contain many bioactive compounds with drug efficacy. Recent evidence demonstrates that it is helpful to various diseases, such as Alzheimer's disease, immunoregulatory, and many types of cancer. Furthermore, emerging pieces of evidence have shown that different active molecules in H. erinaceus have different functions on different organs in different diseases via the different mechanisms. Drawing on current research results, this review mainly focuses on the therapeutic effects of H. erinaceus on various diseases of multiple physiological systems, including the nervous system, digestive system, circulatory system, and immune system. This paper also discusses systematically the efficient protection of H. erinaceus against the diseases from the intricate experimental proofs by using the systematic viewpoints, which provides a framework for future research directions.
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Distribution bias of the sequence matching between exons and introns in exon joint and EJC binding region in C. elegans.
J. Theor. Biol.
PUBLISHED: 06-01-2014
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We propose a mechanism that there are matching relations between mRNA sequences and corresponding post-spliced introns, and introns play a significant role in the process of gene expression. In order to reveal the sequence matching features, Smith-Waterman local alignment method is used on C. elegans mRNA sequences to obtain optimal matched segments between exon-exon sequences and their corresponding introns. Distribution characters of matching frequency on exon-exon sequences and sequence characters of optimal matched segments are studied. Results show that distributions of matching frequency on exon-exon junction region have obvious differences, and the exon boundary is revealed. Distributions of the length and matching rate of optimal matched segments are consistent with sequence features of siRNA and miRNA. The optimal matched segments have special sequence characters compared with their host sequences. As for the first introns and long introns, matching frequency values of optimal matched segments with high GC content, rich CG dinucleotides and high ?CG values show the minimum distribution in exon junction complex (EJC) binding region. High ?CG values in optimal matched segments are main characters in distinguishing EJC binding region. Results indicate that EJC and introns have competitive and cooperative relations in the process of combining on protein coding sequences. Also intron sequences and protein coding sequences do have concerted evolution relations.
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Hg? removal from flue gas by ionic liquid/H?O?.
J. Hazard. Mater.
PUBLISHED: 05-22-2014
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1-Alkyl-3-methylimidazolium chloride ionic liquids ([Cnmim] Cl, n=4, 6, 8) were prepared. The ionic liquid was then mixed with hydrogen peroxide (H2O2) to form an absorbent. The Hg(0) removal performance of the absorbent was investigated in a gas/liquid scrubber using simulated flue gas. It was found that the ionic liquid/H2O2 mixture was an excellent absorbent and could be used to remove Hg(0) from flue gas. When the mass ratio of H2O2 to ionic liquid was 0.5, the absorbent showed high Hg(0) removal efficiency (up to 98%). The Hg(0) removal efficiency usually increased with the absorption temperature, while decreased with the increase of alkyl chain length in ionic liquid molecule. The Hg(0) removal mechanism involved with Hg(0) oxidation by H2O2 and Hg(2+) transfer from aqueous phase to ionic liquid phase.
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Olig2 overexpression accelerates the differentiation of mouse embryonic stem cells into oligodendrocyte progenitor cells in vitro.
Dev. Growth Differ.
PUBLISHED: 05-19-2014
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Oligodendrocyte progenitor cells (OPCs) transplantation is receiving considerable attention in the field of regenerative medicine therapy for demyelinating diseases. Although embryonic stem cells (ESCs) have been successfully induced to differentiate into OPCs with cytokines cocktails in vitro, the regulatory roles of many key transcription factors in this process are not clear. Here, we introduced oligodendrocyte lineage transcription factor 2 (Olig2), a basic helix-loop-helix transcription factor, into mouse embryonic stem cells (mESCs) to investigate its effects on the differentiation of mESCs into OPCs. The results showed that Olig2 overexpression alone did not affect pluripotency of mESCs, but in the stimulation of differentiating cocktails, Olig2 accelerated mESCs to differentiate into OPCs, shortening the induction time span from normal 21 days to 11 days. Further study demonstrated the Olig2-mESCs derived OPCs were able to differentiate into C-type natriuretic peptid (CNP) and Myelin Basic Protein (MBP) positive mature oligodendrocytes (OLs) in vitro, suggesting these induced OPCs might be favorable for myelin regeneration in vivo.
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Differential digestion of human milk proteins in a simulated stomach model.
J. Proteome Res.
PUBLISHED: 04-04-2014
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A key element in understanding how human milk proteins support the health and development of the neonate is to understand how individual proteins are affected during digestion. In the present study, a dynamic gastric model was used to simulate infant gastric digestion of human milk, and a subsequent proteomic approach was applied to study the behavior of individual proteins. A total of 413 human milk proteins were quantified in this study. This approach demonstrated a high degree of variability in the susceptibility of human milk proteins to gastric digestion. Specifically this study reports that lipoproteins are among the class of slowly digested proteins during gastric processes. The levels of integral lysozyme C and partial lactadherin in milk whey increase over digestion. Mucins, ribonuclease 4, and macrophage mannose receptor 1 are also resistant to gastric digestion. The retention or enhancement in whey protein abundance can be ascribed to the digestive release of milk-fat-globule-membrane or immune-cell enclosed proteins that are not initially accessible in milk. Immunoglobulins are more resistant to digestion compared to total milk proteins, and within the immunoglobulin class IgA and IgM are more resistant to digestion compared to IgG. The gastric digestion of milk proteins becomes more apparent from this study.
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Evaluating the association of polymorphisms in the HAP1 gene with lung cancer risk: a meta-analysis.
Tumour Biol.
PUBLISHED: 04-03-2014
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Studies on the relationship of HAP1 polymorphisms (-141 T?>?G; 1349 T?>?G) and lung cancer risk to date indicated controversial results. This study was devised to clarify whether the polymorphisms predispose to lung cancer. We searched Embase and PubMed up to March 2014 to identify relevant studies. Data from the eligible studies were independently extracted by two investigators. Pooled odds ratio (OR) was calculated to assess the associations between lung cancer risk and the abovementioned polymorphisms. A total of 15 case-control studies were included in this meta-analysis. Both overall analysis and stratified analysis by ethnicity and smoking status indicated no association between lung cancer risk and the 1349 T?>?G polymorphism. However, a significantly reduced risk of lung cancer was found among carriers of the GG genotype of the -141 T?>?G polymorphism, as compared with those of the TT genotype (homozygote model: OR?=?0.82, 95 % confidence interval (CI) 0.73 to 0.93, P OR?=?0.002). Likewise, the GG genotype was also found to decrease lung cancer risk compared to the GT?+?TT genotypes (recessive model: OR?=?0.82, 95 % CI 0.73 to 0.92, P OR?=?0.001). Our meta-analysis suggests that the -141 T?>?G polymorphism, but not the 1349 T?>?G polymorphism, may have protective effects for lung cancer.
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Breast cancer awareness among women in Eastern China: a cross-sectional study.
BMC Public Health
PUBLISHED: 03-26-2014
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High breast cancer mortality has been attributed to lack of public awareness, which leads to late diagnoses. As little is known about the level of knowledge and awareness of breast cancer in China, this study was designed to explore it among women in Eastern China.
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Resolution of deep angiosperm phylogeny using conserved nuclear genes and estimates of early divergence times.
Nat Commun
PUBLISHED: 03-24-2014
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Angiosperms are the most successful plants and support human livelihood and ecosystems. Angiosperm phylogeny is the foundation of studies of gene function and phenotypic evolution, divergence time estimation and biogeography. The relationship of the five divergent groups of the Mesangiospermae (~99.95% of extant angiosperms) remains uncertain, with multiple hypotheses reported in the literature. Here transcriptome data sets are obtained from 26 species lacking sequenced genomes, representing each of the five groups: eudicots, monocots, magnoliids, Chloranthaceae and Ceratophyllaceae. Phylogenetic analyses using 59 carefully selected low-copy nuclear genes resulted in highly supported relationships: sisterhood of eudicots and a clade containing Chloranthaceae and Ceratophyllaceae, with magnoliids being the next sister group, followed by monocots. Our topology allows a re-examination of the evolutionary patterns of 110 morphological characters. The molecular clock estimates of Mesangiospermae diversification during the late to middle Jurassic correspond well to the origins of some insects, which may have been a factor facilitating early angiosperm radiation.
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Effects of essential oil supplementation of a low-energy diet on performance, intestinal morphology and microflora, immune properties and antioxidant activities in weaned pigs.
Anim. Sci. J.
PUBLISHED: 03-06-2014
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A total of 144 weaned piglets were used to evaluate the effects of essential oil (EO) supplementation of a low-energy diet on performance, apparent nutrient digestibility, small intestinal morphology, intestinal microflora, immune properties and antioxidant activities in weaned pigs. Pigs received a low-energy diet (negative control, NC, digestible energy?=?3250?kcal/kg), NC plus 0.025% EO or a positive control diet (PC, digestible energy?=?3400?kcal/kg) for 28 days. Growth performance was similar between the EO group and PC group. However, EO supplementation increased (P?
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Role of MR-DWI and MR-PWI in the radiotherapy of implanted pulmonary VX-2 carcinoma in rabbits.
Chin. J. Cancer Res.
PUBLISHED: 03-04-2014
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To detect the activity of tumor cells and tumor blood flow before and after the radiotherapy of implanted pulmonary VX-2 carcinoma in rabbit models by using magnetic resonance diffusion-weighted imaging (MR-DWI) and magnetic resonance perfusion weighted imaging (MR-PWI), and to evaluate the effectiveness and safety of the radiotherapy based on the changes in the MR-DWI and MR-PWI parameters at different treatment stages.
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N-methyl-D-aspartate receptor antagonist MK-801 prevents apoptosis in rats that have undergone fetal spinal cord transplantation following spinal hemisection.
Exp Ther Med
PUBLISHED: 02-27-2014
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Spinal cord injury is the main cause of paraplegia, but effective therapies for it are lacking. Embryonic spinal cord transplantation is able to repair spinal cord injury, albeit with a large amount of neuronal apoptosis remaining in the spinal cord. MK-801, an N-methyl-D-aspartate (NMDA) receptor antagonist, is able to reduce cell death by decreasing the concentration of excitatory amino acids and preventing extracellular calcium ion influx. In this study, the effect of MK-801 on the apoptosis of spinal cord neurons in rats that have received a fetal spinal cord (FSC) transplant following spinal hemisection was investigated. Wistar rats were divided into three groups: Spinal cord hemisection injury with a combination of FSC transplantation and MK-801 treatment (group A); spinal cord hemisection injury with FSC transplantation (group B); and spinal cord injury with insertion of a Gelfoam pledget (group C). The rats were sacrificed 1, 3, 7 and 14 days after the surgery. Apoptosis in spinal slices from the injured spinal cord was examined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling reaction, and the expression of B-cell lymphoma-2 (Bcl-2) was measured by immunohistochemistry. The positive cells were quantitatively analyzed using a computer image analysis system. The rate of apoptosis and the positive expression of Bcl-2 protein in the spinal cord neurons in the three groups decreased in the following order: C>B>A (P<0.05) and A>B>C (P<0.05), respectively. This indicates that treatment with the NMDA receptor antagonist MK-801 prevents apoptosis in the spinal cord neurons of rats that have undergone FSC transplantation following spinal hemisection.
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Self-propagating high-temperature synthesis for compound thermoelectrics and new criterion for combustion processing.
Nat Commun
PUBLISHED: 02-20-2014
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The existing methods of synthesis of thermoelectric (TE) materials remain constrained to multi-step processes that are time and energy intensive. Here we demonstrate that essentially all compound thermoelectrics can be synthesized in a single-phase form at a minimal cost and on the timescale of seconds using a combustion process called self-propagating high-temperature synthesis. We illustrate this method on Cu2Se and summarize key reaction parameters for other materials. We propose a new empirically based criterion for sustainability of the combustion reaction, where the adiabatic temperature that represents the maximum temperature to which the reacting compact is raised as the combustion wave passes through, must be high enough to melt the lower melting point component. Our work opens a new avenue for ultra-fast, low-cost, large-scale production of TE materials, and provides new insights into combustion process, which greatly broaden the scope of materials that can be successfully synthesized by this technique.
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Design, synthesis, and osteogenic activity of daidzein analogs on human mesenchymal stem cells.
ACS Med Chem Lett
PUBLISHED: 02-13-2014
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Osteoporosis is caused by an overstimulation of osteoclast activity and the destruction of the bone extracellular matrix. Without the normal architecture, osteoblast cells are unable to rebuild phenotypically normal bone. Hormone replacement therapy with estrogen has been effective in increasing osteoblast activity but also has resulted in the increased incidence of breast and uterine cancer. In this study we designed and synthesized a series of daidzein analogs to investigate their osteogenic induction potentials. Human bone marrow derived mesenchymal stem cells (MSCs) from three different donors were treated with daidzein analogs and demonstrated enhanced osteogenesis when compared to daidzein treatment. The enhanced osteogenic potential of these daidzein analogs resulted in increased osterix (Sp7), alkaline phosphatase (ALP), osteopontin (OPN), and insulin-like growth factor 1 (IGF-1), which are osteogenic transcription factors that regulate the maturation of osteogenic progenitor cells into mature osteoblast cells.
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Postoperative pain in treatment of spontaneous pneumothorax with limited two-port thoracoscopy.
Pak J Med Sci
PUBLISHED: 02-09-2014
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To investigate effects of the limited two-port video assisted thoracic surgery on treatment of spontaneous pneumothorax.
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What is Visualize?

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

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

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