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Find video protocols related to scientific articles indexed in Pubmed.
Deep localized distortion of alternating bonds and reduced transport of charged carriers in conjugated polymers under photoexcitation.
Nanoscale
PUBLISHED: 11-20-2014
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In a real bulk heterojunction polymer solar cell, after exciton separation in the heterojunction, the resulting negatively-charged carrier, a polaron, moves along the polymer chain of the acceptor, which is believed to be of significance for the charged carrier transport properties in a polymer solar cell. During the negative polaron transport, due to the external light field, the polaron, which is re-excited and induces deep localization, also forms a new local distortion of the alternating bonds. It is revealed that the excited polaron moves more slowly than the ground-state polaron. Furthermore, the velocity of the polaron moving along the polymer chain is crucially dependent on the photoexcitation. With an increase in the intensity of the optical field, the localization of the excited polaron will be deepened, with a decrease of the polaron's velocity. It is discovered that, for a charged carrier, photoexcitation is a significant factor in reducing the efficiency during the charged carrier transport in polymer solar cells. Mostly, the deep trapping effect of charged carrier in composite conjugated polymer solar cell presents an opportunity for the future application in nanoscale memory and imaging devices.
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Structural dependence of silver nanowires on polyvinyl pyrrolidone (PVP) chain length.
Nanotechnology
PUBLISHED: 11-19-2014
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The effect of the chain length of polyvinyl pyrrolidone (PVP) on the structures of silver nanowires (AgNWs) is explored in this study. It was found in the experiments that PVP, when serving as a capping agent, has a great impact on the morphology and structure of AgNWs. By means of a series of experiments and the inquiry of the growth mechanism, the critical minimum PVP chain length for the successful formation of uniform nanowires was discovered, below which only nanoparticles or short nanorods can be obtained. Surprisingly, a core-shell structure of a nanowire with a polycrystal was observed when PVP with a very long chain length was employed in the processing.
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[Effects of combined applications of pig manure and chemical fertilizers on CH4 and N2O emissions and their global warming potentials in paddy fields with double-rice cropping].
Huan Jing Ke Xue
PUBLISHED: 10-24-2014
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A field experiment was carried out to study the effects of combined applications of pig manure and chemical fertilizers on CH4 and N2O emissions, which were measured using the static chamber/gas chromatography method, and their global warming potentials in typical paddy fields with double-rice cropping in Hunan province. The results showed that the combined applications of pig manure and chemical fertilizers did not change the seasonal patterns of CH4 and N2O emissions from paddy soils, but significantly changed the magnitudes of CH4 and N2O fluxes in rice growing seasons as compared with sole application of chemical fertilizers. During the two rice growing seasons, the cumulative CH4 emissions for the pig manure and chemical nitrogen (N) fertilizer each contributing to 50% of the total applied N (1/2N + PM) treatment were higher than those for the treatments of no N fertilizer (ON), half amount of chemical N fertilizer (1/2N) and 100% chemical N fertilizer (N) by 54.83%, 33.85% and 43.30%, respectively (P < 0.05), whilst the cumulative N2O emissions for the 1/2N + PM treatment were decreased by 67.50% compared with N treatment, but increased by 129.43% and 119.23% compared with ON and 1/2N treatments, respectively (P < 0.05). CH4 was the dominant contributor to the global warming potential (GWP) in both rice growing seasons, which contributed more than 99% to the integrated GWP of CH4 and N2O emissions for all the four treatments. Both GWP and yield-scaled GWP for the treatment of 1/2N + PM were significantly higher than the other three treatments. The yield-scaled GWP for the treatment of 1/2N + PM was higher than those for the N, 1/2N and ON treatments by 58.21%, 26.82% and 20. 63%, respectively. Therefore, combined applications of pig manure and chemical fertilizers in paddy fields would increase the GWP of CH4 and N2O emissions during rice growing seasons and this effect should be considered in regional greenhouse gases emissions inventory.
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[Research on the influence of urban land use structure and pattern on nitrogen, phosphorus of wetland water environment in Xianlin New Town of Nanjing].
Huan Jing Ke Xue
PUBLISHED: 10-24-2014
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The 10 typical wetlands in Xianlin New Townof Nanjing were classified into three categories, including rural wetland, suburban wetland, and urban wetland according to the influence of urbanization as well as the characteristics of wetland and LUCC of catchment regions. RDA was used to analyse the relationships between nitrogen and phosphorus in urban wetland and various types and patterns of land use. It was found that the water quality of the urban wetlands presented to be worse than that from rural wetlands, followed by sub urban wetlands. Secondly, according to all investigated wetlands, TP and TN turned out to be higher during the wet seasons than dry seasons. In addition, significant differences of TP were observed between wet and dry seasons for rural and suburban wetlands, and it was not so obvious for urban wetlands. However, the differences of TN was opposite to that of TP. Thirdly, factors affecting the water quality of wetlands were comprised of types and patterns of land use, and thus significant positive relationships were found between the concentrations of TN and TP and the impervious land, while negative correlations for meadows, woodlands and wetlands. What's more, higher remarkable differences were found in wetlands than those from meadows and woodlands. Regarding to patterns of land use, TP, TN concentrations were negatively correlated with the average patch shape in the dry and wet seasons, whereas positively relationships were observed for patch density and diversity index; furthermore, with refer to the impact of adjacent landscape, significant relationships were found between the content of TN and the patterns of land use and thus, a negative correlation in the wet season and a positive correlation in the dry season were observed, respectively.
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Interband ? plasmon of graphene: strong small-size and field-enhancement effects.
Phys Chem Chem Phys
PUBLISHED: 10-02-2014
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The interband ? plasmon of graphene has energy corresponding to the ultraviolet (UV) wave band, and hence is promising for UV nanophotonics and nanooptoelectronics. However, its special size effect and electric field-enhancement effect have not been well understood. Here, we have investigated the far-field optical extinction and near-field enhancement features of the interband ? plasmon in a graphene nanodisk using discrete dipole approximation and finite-difference time-domain methods. Very interestingly, it has been found that the in-plane (transverse mode) optical extinction peak of monolayer graphene firstly significantly red shifts with increasing diameter, but then tends to a saturation value when the diameter is above 20 nm, showing a strong small-size-sensitive effect. Furthermore, the transverse mode optical extinction peak obviously blue shifts with increasing thickness when the thickness is relatively small. Significantly, the corresponding local electric field enhancement factor produced by the plasmon, which can be found to be as large as several tens, firstly increases with the increase of the size and then reaches a maximum value at only several nanometers in size. Such an ultrasmall-size-sensitive plasmon in the UV region endows graphene dots with new promising potential uses in ultrasmall photo-electric devices and nanoantennas, and in UV enhancers.
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[Study on transient absorption spectrum of tungsten nanoparticle with HepG2 tumor cell].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 10-02-2014
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Significance of this study lies in tungsten nano materials can be used as a preliminary innovative medicines applied basic research. This paper investigated the inhibition of tungsten nanoparticles which effected on human hepatoma HepG2 cells by MTT. The authors use transient absorption spectroscopy (TAS) technology absorption and emission spectra characterization of charge transfer between nanoparticles and tumor cell. The authors discussed the role of the tungsten nanoparticles in the tumor early detection of the disease and its anti-tumor properties. In the HepG2 experiments system, 100-150 microg x mL(-1) is the best drug concentration of anti-tumor activity which recact violently within 6 hours and basically completed in 24 hours. The results showed that transient absorption spectroscopy can be used as tumor detection methods and characterization of charge transfer between nano-biosensors and tumor cells. Tungsten nanoparticles have potential applications as anticancer drugs.
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Pre-emptive parecoxib and post-operative cognitive function in elderly patients.
Int Psychogeriatr
PUBLISHED: 09-16-2014
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ABSTRACT Background: To investigate the effect of pre-emptive parecoxib sodium, given in addition to routine analgesic treatment, on post-operative cognitive function in elderly patients. Methods: Seventy elderly patients were included, who were 65-82 years of age, 48-75 kg of weight, and ASA grade I-II. Preoperative mini mental state examination (MMSE) score was ?21 points. Patients were randomly divided into two groups: control group (group C) and parecoxib sodium group (group P). Before induction of general anesthesia, 40 mg of parecoxib sodium was injected intravenously in group P and the same volume of saline was injected in group C. Patient-controlled intravenous analgesia (PCIA) containing fentanyl and tramadol was used for post-operative pain control. A 3 ml blood sample was obtained from the peripheral vein one day before surgery, 1, 4, 24, and 72 h after surgery, and plasma cortisol, IL-6 and S100? concentrations were measured. Cognitive function was evaluated by measuring the MMSE score and a neurological test battery within 72 h after surgery. The occurrence of post-operative cognitive dysfunction (POCD), the dosage of fentanyl and tramadol used in PCIA, and the rate of additional fentanyl administration were recorded. Results: Compared to group C, post-operative plasma cortisol concentration decreased, the amount of fentanyl and tramadol used in PCIA was reduced, the rate of additional fentanyl administration decreased, and the rate of POCD was reduced in group P (P < 0.05). Conclusion: Pre-emptive analgesia with 40 mg of parecoxib sodium can reduce the incidence of POCD in elderly patients.
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BIIB021, a novel Hsp90 inhibitor, sensitizes esophageal squamous cell carcinoma to radiation.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-31-2014
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BIIB021 is a novel, orally available inhibitor of heat shock protein 90 (Hsp90) that is currently in phase I/II clinical trials. BIIB021 induces the apoptosis of various types of tumor cells in vitro and in vivo. The aim of this study is to investigate the effect of BIIB021 on the radiosensitivity of esophageal squamous cell carcinoma (ESCC). The results indicated that BIIB021 exhibited strong antitumor activity in ESCC cell lines, either as a single agent or in combination with radiation. BIIB021 significantly downregulated radioresistant proteins including EGFR, Akt, Raf-1 of ESCC cell lines, increased apoptotic cells and enhanced G2 arrest that is more radiosensitive cell cycle phase. These results suggest that this synthetic Hsp90 inhibitor simultaneously affects multiple pathways involved in tumor development and progression in the ESCC setting and may represent a better strategy for the treatment of ESCC patients, either as a monotherapy or a radiosensitizer.
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A silver nanoparticle embedded hydrogel as a substrate for surface contamination analysis by surface-enhanced Raman scattering.
Analyst
PUBLISHED: 08-19-2014
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A surface enhanced Raman scattering (SERS) substrate, capable of extracting small amounts of organic species from surfaces of different types of materials with variable roughness, has been fabricated. The substrate consists of Ag NPs encapsulated in poly(vinyl alcohol) (PVA) hydrogels, commonly known as PVA "slime". Unlike traditional SERS substrates, such as colloidal suspensions, the resulting PVA slime SERS substrate presents good viscoelasticity, allowing it to conform to the surface of various materials of arbitrary roughness. Surfaces of different materials, including sandpapers, cotton, metal, and wood, previously contaminated with nile blue A (NBA) were analyzed with the PVA slime SERS substrate. Limits of detection (LOD) as low as 100 ppb (0.79 ng in a total amount on an area of ?3 cm(2)) were achieved for all surfaces tested. Pesticides and Sudan red III on the glass surface have also been detected, with a LOD of 1.6 ng per ?3 cm(2).
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Novel and facile method, dynamic self-assemble, to prepare SnO?/rGO droplet aerogel with complex morphologies and their application in supercapacitors.
ACS Appl Mater Interfaces
PUBLISHED: 08-18-2014
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A facile and novel method to prepare SnO2/reduced graphene oxide (rGO) droplet aerogels with complex morphologies had been developed. This method has been named dynamic self-assemble. Aerogels with both "egg-tart" and "mushroom" shapes were obtained by this method. The changes in the graphene oxide (GO) droplet morphologies during the dynamic process of a GO droplet falling into a SnCl2 target solution were monitored using a high speed camera. The formed SnO2/rGO aerogels were then characterized by Raman spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The microstructures of the SnO2/rGO aerogels were observed with scanning electron microscopy and transmission electron microscopy. Finally, the SnO2/rGO droplet aerogels were used as the electrode material in a symmetrical two-electrode supercapacitor and the electrochemical performance of the supercapacitor was investigated using cyclic voltammetry and galvanostatic charge/discharge methods. The SnO2/rGO electrodes demonstrated excellent electrochemical performance and stability. At a scan rate of 5 mV/s, their highest gravimetric and volumetric specific capacitances were 310 F/g and 180 F/cm(3), respectively, and their energy and power densities were as high as 30 Wh·kg(-1) and 8.3 kW·kg(-1), respectively.
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[Impact of the number of lymph nodes dissected on the prognosis of G3 advanced gastric cancer].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 07-30-2014
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To explore the risk factors associated with the prognosis in poorly differentiated(G3) advanced gastric cancer (AGC) and the effect of number of harvested lymph nodes on the prognosis.
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Learning From Adaptive Neural Dynamic Surface Control of Strict-Feedback Systems.
IEEE Trans Neural Netw Learn Syst
PUBLISHED: 07-29-2014
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Learning plays an essential role in autonomous control systems. However, how to achieve learning in the nonstationary environment for nonlinear systems is a challenging problem. In this paper, we present learning method for a class of n th-order strict-feedback systems by adaptive dynamic surface control (DSC) technology, which achieves the human-like ability of learning by doing and doing with learned knowledge. To achieve the learning, this paper first proposes stable adaptive DSC with auxiliary first-order filters, which ensures the boundedness of all the signals in the closed-loop system and the convergence of tracking errors in a finite time. With the help of DSC, the derivative of the filter output variable is used as the neural network (NN) input instead of traditional intermediate variables. As a result, the proposed adaptive DSC method reduces greatly the dimension of NN inputs, especially for high-order systems. After the stable DSC design, we decompose the stable closed-loop system into a series of linear time-varying perturbed subsystems. Using a recursive design, the recurrent property of NN input variables is easily verified since the complexity is overcome using DSC. Subsequently, the partial persistent excitation condition of the radial basis function NN is satisfied. By combining a state transformation, accurate approximations of the closed-loop system dynamics are recursively achieved in a local region along recurrent orbits. Then, the learning control method using the learned knowledge is proposed to achieve the closed-loop stability and the improved control performance. Simulation studies are performed to demonstrate the proposed scheme can not only reuse the learned knowledge to achieve the better control performance with the faster tracking convergence rate and the smaller tracking error but also greatly alleviate the computational burden because of reducing the number and complexity of NN input variables.
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[A case report of carcinoma in situ of the bladder invading the prostate following BCG therapy].
Hinyokika Kiyo
PUBLISHED: 07-09-2014
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A 85-year-old man achieved complete response after a course of intravesical instillation of Bacillus Calmette Guerin (BCG) therapy for carcinoma in situ (CIS) of the bladder. Two year later, urine cytology became class III. We performed random biopsy of the bladder and split urine cytology of the bilateral upper urinary tract, but none of these examinations revealed any malignant features. After a month, he consulted orthopedics for lumbago. He was indicated to have a metastatic bone tumor, and positron emission tomography-computed tomography (PET-CT) showed a hypermetabolic mass in the prostate. A transperineal needle biopsy of the prostate revealed the urothelial carcinoma (UC). Our diagnosis was invasion of CIS of the bladder into the prostate. In such cases, we recommend a needle biopsy of the prostate in addition to a transurethral biopsy of the bladder and prostate.
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Long-term effect of laser-induced ocular hypertension on the cone electroretinogram and central macular thickness in monkeys.
Photomed Laser Surg
PUBLISHED: 07-04-2014
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The purpose of this study was to investigate the long-term effect of laser-induced ocular hypertension on the cone electroretinogram (ERG) and retinal thickness in monkeys.
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Terahertz parametric oscillator based on KTiOPO? crystal.
Opt Lett
PUBLISHED: 07-01-2014
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KTiOPO? (KTP) crystal is used as the nonlinear medium in a surface-emitted terahertz-wave parametric oscillator for the first time. The oscillating Stokes beam propagates along the x axis of the KTP crystal, the pumping beam propagates with a small incident angle ?(ext) to the x axis, and the polarizations of the pumping beam, the Stokes beam, and the THz wave are along the z axis. When ?(ext) is changed from 1.250° to 6.000°, the THz wave is intermittently tuned from 3.17 to 3.44 THz, from 4.19 to 5.19 THz, and from 5.55 to 6.13 THz. The maximum output of the THz wave is 336 nJ, obtained at 5.72 THz with a pumping energy of 80 mJ. The two frequency gaps, from 3.44 to 4.19 THz and from 5.19 to 5.55 THz, are located in the vicinities of the A? modes of 134 and 178.7??cm?¹, which are strongly infrared absorbing.
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Dimensional reduction of a V1 ring model with simple and complex cells.
J Comput Neurosci
PUBLISHED: 06-25-2014
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In this paper, we extend a framework for constructing low-dimensional dynamical systems models of mammalian primary visual cortex to a cortical network model that incorporates the full nonlinear effects of complex cells. The procedure consists of capturing the essential dynamics in a low-dimensional subspace using empirical methods, then recasting the equations in the reduced vector space. Previously, we considered visual cortical network models consisting of only simple cells with nearly linear responses to external stimuli. Here we show that fully nonlinear effects can be incorporated by examining the dimensional reduction of an idealized ring model of V1 with both simple and complex cells. We found it expedient to divide the subspace into four separate neuronal populations: excitatory simple, excitatory complex, inhibitory simple and inhibitory complex. In order to reproduce the fluctuation-driven dynamics in this reduced space, we incorporated (1) white noises with different intensities into individual neuronal populations, and (2) firing rate estimates to capture the probability of firing due to subthreshold fluctuations. With a more accurate, fitted connectivity, our modified dimensional reduced models can reproduce the firing rates, circular variances and modulation ratios observed in the original ring model.
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Application of molecularly imprinted polymers in wastewater treatment: a review.
Environ Sci Pollut Res Int
PUBLISHED: 06-22-2014
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Molecularly imprinted polymers are synthetic polymers possessing specific cavities designed for target molecules. They are prepared by copolymerization of a cross-linking agent with the complex formed from a template and monomers that have functional groups specifically interacting with the template through covalent or noncovalent bonds. Subsequent removal of the imprint template leaves specific cavities whose shape, size, and functional groups are complementary to the template molecule. Because of their predetermined selectivity, molecularly imprinted polymers (MIPs) can be used as ideal materials in wastewater treatment. Especially, MIP-based composites offer a wide range of potentialities in wastewater treatment. This paper reviews the latest applications of MIPs in wastewater treatment, highlights the development of MIP-based composites in wastewater, and offers suggestions for future success in the field of MIPs.
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[Observation on therapeutic effect of polycystic ovary syndrome of damp-phlegm constitution treated with embedding therapy on back-shu points and front-mu points combined with needle-pricking therapy on Sifeng (EX-UE 10)].
Zhongguo Zhen Jiu
PUBLISHED: 06-21-2014
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To investigate the effectiveness of polycystic ovary syndrome (PCOS) of damp-phlegm constitution treated with embedding therapy on back-shu points and front-mu points and needle-pricking therapy on Sifeng (EX-UE 10).
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[Optimization of electrode location and size on simulation in electric field distribution of atrial defibrillation].
Zhongguo Yi Liao Qi Xie Za Zhi
PUBLISHED: 06-20-2014
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A distributed simulation method of electric field based on the atrial defibrillation of the heart modeling and finite element solution is proposed in this study. In order to solve the problem that ordinary clinical trials could not measure the actual distribution of the defibrillation electric field in the heart accurately, this method provides a research tool for electrical defibrillation. A complete atrial anatomical structure in the heart model is used in the research, the finite element method is proceeded to solve; Three parameters: defibrillation threshold voltage, the high field strength rate and the defibrillation threshold energy are set to evaluate the effect of defibrillation. The heart electric field distributions of transvenous atrial defibrillation with different electrode locations or sizes are simulated. The simulation results and the reported results match fairly well, which initially verify the feasibility of this method.
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Effects of polyprenols from pine needles of Pinus massoniana on ameliorating cognitive impairment in a D-galactose-induced mouse model.
Age (Dordr)
PUBLISHED: 06-18-2014
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Cognitive deficiency and oxidative stress have been well documented in aging and in neurodegenerative disorders such as Alzheimer's disease. In this study, we assessed the therapeutic effect of polyprenols on D-galactose-induced cognitive impairment in mice by testing on of behavioral and cognitive performance. In order to explore the possible role of polyprenols against D-galactose-induced oxidative damages, we assessed various biochemical indicators. Chronic administration of D-galactose (150 mg/kg·d, s.c.) for 7 weeks significantly impaired cognitive performance (both in step-through passive and active avoidance tests) and locomotor activity (in open-field test) and the ability of spatial learning and memory (in Morris water maze test) compared with the control group. The results revealed that polyprenols treatment for 2 weeks significantly ameliorated model mice's cognitive performance and oxidative defense. All groups of polyprenols enhanced the learning and memory ability in step-through passive and active avoidance tests, locomotor activity in open-field test, and the ability of spatial learning and memory in Morris water maze test. Furthermore, high and middle level of polyprenols significantly increased total antioxidative capacity (T-AOC), glutathione peroxidase (GSH-Px), super oxide dismutase (SOD) activity, neprilysin (NEP), and ?-site A?PP cleaving enzyme 1 (BACE1) expression, while nitric oxide (NO), nitric oxide synthase (NOS) activity, malondialdehyde (MDA) concentration, and the level of A?1-42 and presenilin 1 (PS1) were decreased. Polyprenols have a significant relieving effect on learning, memory, and spontaneous activities in a D-galactose-induced mouse model and ameliorates cognitive impairment and biochemical dysfunction in mice. In summary, we have demonstrated that polyprenols may ameliorate memory and cognitive impairment via enhancing oxidative defense and affecting generation and dissimilation of A?-related enzymes, suggesting that polyprenols represent a novel drug for treating Alzheimer's disease.
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Inhibition of Wnt/?-catenin signaling promotes epithelial differentiation of mesenchymal stem cells and repairs bleomycin-induced lung injury.
Am. J. Physiol., Cell Physiol.
PUBLISHED: 06-04-2014
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Idiopathic pulmonary fibrosis is a progressive lung disorder of unknown etiology. Previous studies have shown that aberrant activation of the Wnt/?-catenin signaling cascade occurs in lungs of patients with idiopathic pulmonary fibrosis. Given the important roles of the Wnt/?-catenin signaling pathway in the development of pulmonary fibrosis, we targeted this pathway for the intervention of pulmonary fibrosis with XAV939, a small molecule that specifically inhibits Tankyrase 1/2, eventually leading to the degradation of ?-catenin and suppression of the Wnt/?-catenin signaling pathway. Our results demonstrated that XAV939 significantly inhibited the activation of Wnt/?-catenin signaling and attenuated bleomycin-induced lung fibrosis in mice, and thus improved the survival of mice with lung injury. Interestingly, previous investigations have confirmed that endogenous and exogenous mesenchymal stem cells could be recruited to the injured lung, although the exact effects of these cells are debatable. To determine the effect of Wnt/?-catenin signaling in the epithelial differentiation of bone marrow-derived mesenchymal stem cells (BM-MSCs), we established a coculture system that contains BM-MSCs and alveolar type II epithelial cells. The in vitro experiments demonstrated that XAV939 could promote the differentiation of BM-MSCs into an epithelium-like phenotype in the coculture system. We also found that XAV939 could inhibit the proliferation and myofibroblast differentiation of NIH/3T3 fibroblasts. This work supports that inhibition of the Wnt/?-catenin signaling pathway may be exploited for the treatment of idiopathic pulmonary fibrosis for which effective treatment strategies are still lacking.
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[Metanephric adenoma of kidney: a clinicopathologic study of eight cases].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 05-21-2014
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To study the clinical and histopathologic features of metanephric adenoma (MA).
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Dynamic learning from adaptive neural network control of a class of nonaffine nonlinear systems.
IEEE Trans Neural Netw Learn Syst
PUBLISHED: 05-09-2014
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This paper studies the problem of learning from adaptive neural network (NN) control of a class of nonaffine nonlinear systems in uncertain dynamic environments. In the control design process, a stable adaptive NN tracking control design technique is proposed for the nonaffine nonlinear systems with a mild assumption by combining a filtered tracking error with the implicit function theorem, input-to-state stability, and the small-gain theorem. The proposed stable control design technique not only overcomes the difficulty in controlling nonaffine nonlinear systems but also relaxes constraint conditions of the considered systems. In the learning process, the partial persistent excitation (PE) condition of radial basis function NNs is satisfied during tracking control to a recurrent reference trajectory. Under the PE condition and an appropriate state transformation, the proposed adaptive NN control is shown to be capable of acquiring knowledge on the implicit desired control input dynamics in the stable control process and of storing the learned knowledge in memory. Subsequently, an NN learning control design technique that effectively exploits the learned knowledge without re-adapting to the controller parameters is proposed to achieve closed-loop stability and improved control performance. Simulation studies are performed to demonstrate the effectiveness of the proposed design techniques.
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Hepatocellular carcinoma metastasis to the lacrimal gland: A case report.
Oncol Lett
PUBLISHED: 05-07-2014
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Hepatocellular carcinoma (HCC) is a globally common neoplasm, with regional metastasis associated with >50% of the tumors. Extrahepatic metastasis is also common, with the lungs, diaphragm, abdominal lymph nodes and bone being the most frequently affected regions. However, to the best of our knowledge, HCC metastasis to the lacrimal gland has not been reported in the literature. Only one case of metastasis to the lacrimal sac from a renal cell carcinoma has been reported. The current study presents the case of a 56-year-old male with ocular symptoms who was eventually diagnosed with HCC. The therapeutic alternatives for such cases are also discussed according to the reviewed literature. Clinicians should be watchful for the appearance of tumors in the lacrimal gland in patients with a history of malignancy.
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Quantum molecular dynamics study of expanded beryllium: evolution from warm dense matter to atomic fluid.
Sci Rep
PUBLISHED: 05-06-2014
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By performing quantum molecular dynamics (QMD) simulations, we investigate the equation of states, electrical and optical properties of the expanded beryllium at densities two to one-hundred lower than the normal solid density, and temperatures ranging from 5000 to 30000 K. With decreasing the density of Be, the optical response evolves from the one characteristic of a simple metal to the one of an atomic fluid. By fitting the optical conductivity spectra with the Drude-Smith model, it is found that the conducting electrons become localized at lower densities. In addition, the negative derivative of the electrical resistivity on temperature at density about eight lower than the normal solid density demonstrates that the metal to nonmetal transition takes place in the expanded Be. To interpret this transition, the electronic density of states is analyzed systematically. Furthermore, a direct comparison of the Rosseland opacity obtained by using QMD and the standard opacity code demonstrates that QMD provides a powerful tool to validate plasma models used in atomic physics approaches in the warm dense matter regime.
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Acetaldehyde dehydrogenase 2 (ALDH2) deficiency exacerbates pressure overload-induced cardiac dysfunction by inhibiting Beclin-1 dependent autophagy pathway.
Biochim. Biophys. Acta
PUBLISHED: 05-01-2014
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Mitochondrial aldehyde dehydrogenase 2 (ALDH2) was demonstrated to play cardioprotective roles in cardiovascular diseases. Nonetheless, little is known about the roles and mechanisms of ALDH2 in pressure overload-induced cardiac damages. In this study, we revealed that ALDH2 deficiency overtly exacerbated transverse aortic constriction (TAC)-induced cardiac dysfunction. Cardiomyocyte enlargement was observed in both WT and ALDH2-/- mice in HE-stained myocardial tissue samples at 8weeks post TAC surgery. Mitochondrial morphology and structure were also significantly damaged post TAC surgery and the changes were aggravated in ALDH2-/- TAC hearts. ALDH2 deficiency also depressed myocardial autophagy in hearts at 8weeks post TAC surgery with a potential mechanism of repressing the expression of Beclin-1 and promoting the interaction between Bcl-2 and Beclin-1. These data indicate that ALDH2 deficiency exacerbates the pressure overload induced cardiac dysfunction partly by inhibiting Beclin-1 dependent autophagy pathway. This article is part of a Special Issue entitled: Autophagy and protein quality control in cardiometabolic diseases.
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A novel FGF2 antagonist peptide P8 with potent antiproliferation activity.
Tumour Biol.
PUBLISHED: 04-29-2014
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Some fibroblast growth factors (FGFs) play a critical role in tumorigenesis and progression. Among them, FGF2 was highly expressed in some tumors, and antagonists binding to FGF2 can suppress the growth of tumor cells. Therefore, FGF2 has been considered as an important target in cancer therapy. In this study, we identified a novel FGF2-binding short peptide (P8, PLLQATAGGGS-NH2) using phage display technology and alanine scanning. The P8 peptide suppressed FGF2-induced proliferation with no cytotoxic effect on cells, arrested the cycle at the G0/G1 phase in B16-F10 cells, and downregulated the activation of fibroblast growth factor receptor substrate 2? (FRS2?)/ERK cascade in B16-F10, NIH-H460, and SGC-7901 cells. Besides, P8 peptide can also inhibit the phosphorylation of FRS2? stimulated by FGF1 and KGF2. These implied that P8 peptide may develop as a multi-target antagonist peptide contributing to tumor treatment.
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De-novo synthesis of 2-phenylethanol by Enterobacter sp. CGMCC 5087.
BMC Biotechnol.
PUBLISHED: 04-25-2014
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2-phenylethanl (2-PE) and its derivatives are important chemicals, which are widely used in food materials and fine chemical industries and polymers and it's also a potentially valuable alcohol for next-generation biofuel. However, the biosynthesis of 2-PE are mainly biotransformed from phenylalanine, the price of which barred the production. Therefore, it is necessary to seek more sustainable technologies for 2-PE production.
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[A case report of metastatic renal cell carcinoma to the bladder].
Hinyokika Kiyo
PUBLISHED: 04-25-2014
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70-year-old man was suffering from asymptomatic gross hematuria. Computed tomography demonstrated the mass in the right kidney, bladder, bone and lung. Cystoscopy revealed a solitary, nonpapillary lesion at the right side of the dome. At first, transuretheral resection of bladder tumor was performed. The pathological diagnosis was clear cell carcinoma of unknown origin. Sequentially, retroperitoneoscopic nephrectomy was performed. The pathological diagnosis of the right renal tumor was also clear cell carcinoma. The diagnosis was renal cell carcinoma metastasized to the bladder, bone and lung. To our knowledge, in Japan, this is the 45th case of metastasis to the bladder of renal cell carcinoma in the literature.
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Association between Glutathione S-Transferase T1, M1, and P1 Genotypes and the Risk of Colorectal Cancer.
J. Korean Med. Sci.
PUBLISHED: 04-24-2014
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Glutathione S-transferases (GSTs) are enzymes which play an important role in the neutralization of toxic compounds and eradication of electrophilic carcinogens. Genetic polymorphisms within the genes encoding for GSTs may therefore cause variations in their enzyme activity, which may in turn influence the interindividual susceptibility to cancers. In this study, we aimed to investigate the association between genetic polymorphisms of GSTT1, GSTM1, and GSTP1 and the risk of colorectal cancer (CRC) in 264 cases and 317 controls in a Chinese population. Genotyping was performed by using multiplex PCR (for GSTT1 and GSTM1) and PCR-RFLP (for GSTP1) methods. The association between the polymorphic genotypes and CRC risk was evaluated by deriving odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression analysis. Our results showed that individuals with GSTT1 and GSTM1 null genotypes exhibited a higher risk of CRC (GSTT1, OR,1.66; 95% CI, 1.20-2.31, P=0.003; GSTM1, OR,1.57; 95% CI,1.13-2.18, P=0.007), while no association was observed for GSTP1 (P heterozygous=0.790 or P variant=0.261). Furthermore, individuals who simultaneously carried the null genotypes for both GSTT1 and GSTM1 showed a stronger risk association (OR, 1.95; 95% CI, 1.33-2.85; P<0.001). In conclusion, the GSTT1 and GSTM1 polymorphisms, but not GSTP1, may modulate the CRC risk among Chinese.
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Earlier vegetation green-up has reduced spring dust storms.
Sci Rep
PUBLISHED: 04-24-2014
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The observed decline of spring dust storms in Northeast Asia since the 1950s has been attributed to surface wind stilling. However, spring vegetation growth could also restrain dust storms through accumulating aboveground biomass and increasing surface roughness. To investigate the impacts of vegetation spring growth on dust storms, we examine the relationships between recorded spring dust storm outbreaks and satellite-derived vegetation green-up date in Inner Mongolia, Northern China from 1982 to 2008. We find a significant dampening effect of advanced vegetation growth on spring dust storms (r = 0.49, p = 0.01), with a one-day earlier green-up date corresponding to a decrease in annual spring dust storm outbreaks by 3%. Moreover, the higher correlation (r = 0.55, p < 0.01) between green-up date and dust storm outbreak ratio (the ratio of dust storm outbreaks to times of strong wind events) indicates that such effect is independent of changes in surface wind. Spatially, a negative correlation is detected between areas with advanced green-up dates and regional annual spring dust storms (r = -0.49, p = 0.01). This new insight is valuable for understanding dust storms dynamics under the changing climate. Our findings suggest that dust storms in Inner Mongolia will be further mitigated by the projected earlier vegetation green-up in the warming world.
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[Interdigitating dendritic cell sarcoma/tumor: a clinicopathologic study].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 04-19-2014
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To study the clinicopathologic characteristics and diagnostic criteria of interdigitating dendritic cell sarcoma/tumor (IDCS/T).
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Early Clinical Outcomes and Radiographic Features After Treatment of Cervical Degenerative Disc Disease with the New Zero-Profile Implant: A One-year Follow-up Retrospective Study.
J Spinal Disord Tech
PUBLISHED: 04-18-2014
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Retrospective study of 52 patients who underwent anterior cervical fusion with the new implant.
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Superoleophilic nanoporous polymeric ionic liquids loaded with palladium acetate: Reactants enrichment and efficient heterogeneous catalysts for Suzuki-Miyaura coupling reaction.
J Colloid Interface Sci
PUBLISHED: 04-14-2014
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We report here successful synthesis of superoleophilic, nanoporous polymeric ionic liquids supported palladium acetate (PDVB-[C3vim][SO3CF3]-Pd-xs, where x stands for the weight percentage of palladium acetate), which act as efficient heterogeneous catalysts in Suzuki-Miyaura cross-coupling reaction. PDVB-[C3vim][SO3CF3] support was synthesized from solvothermal copolymerization of divinylbenzene with vinylimidazole without using any templates, followed by functionalized with ionic liquid groups. The resultant PDVB-[C3vim][SO3CF3]-Pd-xs possess large BET surface areas, good stability, homogeneous dispersion of Pd active species, and superwettability for various aromatic reactants, which result in their much improved reactants enrichment property. The above characters make PDVB-[C3vim][SO3CF3]-Pd-xs showed much improved catalytic activity and good recyclability in Suzuki-Miyaura reaction in comparison with those of palladium acetate supported onto activated carbon and ordered mesoporous silica of SBA-15. The superior activity found in PDVB-[C3vim][SO3CF3]-Pd-xs is attributed to synergistic effects between large surface areas and unique enrichment property for various aromatic reactants, which by themselves are capable of enhancing exposition degree of Pd active sites to reactants.
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Differentiation-stimulating potency of differentiated HL60 cells after drug treatment.
Biomed. Pharmacother.
PUBLISHED: 04-03-2014
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Differentiation therapy in the treatment of leukemia is often hampered by limitations on using certain pharmaceutical regents or on the required doses due to various reasons, such as drug-resistance and retinoic acid syndrome. To circumvent these problems, a strategy might be developed on the basis of the ability of drug-differentiated cells to stimulate differentiation in leukemia cells. Using the promyelocytic leukemia cell line HL60 as a cell model, we assessed the differentiation-stimulating potency of differentiated granulocytes and monocytes/macrophages after treatments with all-trans retinoic acid (ATRA) and 12-O-tetradecanoylphorbol-13-acetate (TPA), respectively. ATRA- and TPA-differentiated cells were able to stimulate differentiation in fresh HL60 cells, accompanied by inhibition on cell growth to various extents. The differentiated cells of the second generation, especially those originated from TPA treatment, were as potent as the drugs themselves in stimulating differentiation in fresh HL60 cells. On the basis of "differentiation induced by differentiated cells", we explored the feasibility of ex vivo therapy.
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KCC2 expression changes in Diazepam-treated neonatal rats with hypoxia-ischaemia brain damage.
Brain Res.
PUBLISHED: 03-20-2014
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Hypoxia-ischaemia brain damage (HIBD) is a major type of perinatal brain injury in newborns. In this study, we investigate the short- and long-term neuroprotective effects of Diazepam on neonatal rats with HIBD and the potential mechanisms underlying its protective effects. Seven-day-old Sprague-Dawley rats were subjected to left carotid artery ligation followed by a 2-h exposure to 8% oxygen and 92% nitrogen. Diazepam was administered immediately via intraperitoneal (i.p.) injection after inducing HIBD at a dose of 10 mg kg(-1)8h(-1) for three consecutive days. Three days after HIBD, rats were decapitated, and the extent of brain injury was evaluated using 2,3,5-triphenyltetrazolium chloride (TTC) staining. Additionally, the expression of Potassium-chloride cotransporter-2 (KCC2) was analysed using real-time PCR, Western blot analysis and immunohistochemistry. Three weeks after HIBD, rats were subjected to the Morris water maze (MWM) test and the locomotor activity test to determine the long-term therapeutic effects of Diazepam. We observed that the volume of infarction in the Diazepam group was significantly less (P<0.01) compared with the HIBD group. We also observed that the learning and memory abilities of the Diazepam rats improved significantly compared with the untreated rats (P<0.05) and that the decrease in KCC2 expression was prevented (P<0.01). Early treatment with Diazepam appears to attenuate HIBD and can efficiently improve the long-term learning and memory capabilities of the animal. A potential mechanism underlying these effects may involve preventing the decrease in KCC2 expression.
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Prognostic value of serum AFP, AFP-L3, and GP73 in monitoring short-term treatment response and recurrence of hepatocellular carcinoma after radiofrequency ablation.
Asian Pac. J. Cancer Prev.
PUBLISHED: 03-20-2014
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Alpha-fetoprotein (AFP), Lens culinaris agglutinin-reactive fraction of AFP (AFP-L3), and Golgi protein 73 (GP73) levels have been widely used as tumor markers for the diagnosis of hepatocellular carcinoma (HCC). The aim of this study was to investigate whether these tumor markers could be used to monitor short-term treatment response and recurrence of HCC in patients undergoing radiofrequency ablation (RFA).
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Diagnostic accuracy of contrast-enhanced ultrasound for renal cell carcinoma: a meta-analysis.
Tumour Biol.
PUBLISHED: 03-04-2014
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This meta-analysis aimed to identify the accuracy of contrast-enhanced ultrasonography (CEUS) for the diagnosis of renal cell carcinoma (RCC). We searched PubMed, Web of Science, Google Scholar, Cochrane Library, CISCOM, CINAHL, EBSCO, and CBM databases from inception through August 1, 2013 without language restrictions. Meta-analysis was conducted using STATA version 12.0 and Meta-Disc version 1.4 softwares. We calculated the summary statistics for sensitivity (Sen), specificity (Spe), positive and negative likelihood ratio (LR+/LR-), diagnostic odds ratio (DOR), and receiver operating characteristic (SROC) curve. Eleven studies that met all inclusion criteria were included in this meta-analysis. A total of 567 RCC patients and 313 patients with benign renal tumors were assessed. All renal lesions were histologically confirmed after CEUS. The pooled Sen was 0.88 (95 %CI = 0.85 ? 0.90); the pooled Spe was 0.80 (95 %CI = 0.75 ? 0.85). The pooled LR+ was 4.30 (95 %CI = 2.65 ? 6.99); the pooled negative LR- was 0.11 (95 %CI = 0.05 ? 0.22). The pooled DOR of CEUS in the diagnosis of RCC was 46.97 (95 % CI = 16.72 ? 131.97). The area under the SROC curve was 0.922 (standard error [SE]?= 0.039). We found no evidence for publication bias (t = -1.00, P = 0.342). Our meta-analysis indicates that CEUS may have high diagnostic accuracy in differential diagnosis between benign and malignant renal tumors. Thus, CEUS may be a good tool for the diagnosis of RCC.
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Targeted inhibition of mTOR signaling improves sensitivity of esophageal squamous cell carcinoma cells to cisplatin.
J Immunol Res
PUBLISHED: 02-27-2014
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mTOR is an evolutionarily conserved serine-threonine kinase with a central role in cell growth, invasion, and metastasis of tumors, and is activated in many cancers. The aims of this study were to investigate the expression of mTOR in ESCC tissues and its relationship with progression of ESCC and measure the changes of sensitivity of ESCC cells to cisplatin after cells were treated with mTOR siRNA by WST-8 assays, TUNEL, RT-PCR, and western blots in vitro and in vivo. The results showed that the expression of mTOR was higher in ESCC specimens than that in normal esophageal tissues and its expression was closely correlated with the TNM stage of ESCC. mTOR siRNA significantly increased the sensitivity of the EC9706 cells to cisplatin at proliferation in vitro and in vivo. The growth of ESCC xenografts was significantly inhibited by mTOR siRNA or cisplatin, and the cell number of apoptosis was obviously increased after xenografts were treated with mTOR siRNA or cisplatin alone, especially when mTOR siRNA combined with cisplatin. The present study demonstrates that the expression of mTOR has important clinical significance and inhibition of mTOR pathway by mTOR siRNA can improve the sensitivity of ESCC cells to cisplatin.
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Decreased expression of RASSF1A and up-regulation of RASSF1C is associated with esophageal squamous cell carcinoma.
Clin. Exp. Metastasis
PUBLISHED: 02-26-2014
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The Ras-Association Domain Family 1 (RASSF1) gene, which is located on the small arm of chromosome 3, contains two CpG islands and generates seven transcripts (RASSF1A-RASSF1G) by differential promoter usage and alternative splicing. As the main transcript, RASSF1A, B and C may play different roles in tumorigenesis. The present study was to detect the role of RASSF1A, B and C in esophageal squamous cell carcinoma (ESCC) and clarify the critical CpG sites of RASSF1A, in order to clarify more information on the role of RASSF1 with regard to the pathogenesis of ESCC. Frequent silencing of RASSF1A but not RASSF1B and RASSF1C were found in esophageal cancer cell lines and the silencing of RASSF1A may be reversed by 5-Aza-dC treatment. The aberrant promoter and exon 1 especially exon 1 methylation of RASSF1A induces silencing of its expression in TE13 cell line. Decreased mRNA and protein expression of RASSF1A was observed in ESCC tumor tissues and was associated with RASSF1A promoter and exon 1 methylation status. Unlike RASSF1A, methylation and expression variation of RASSF1B was not found in ESCC tissues. However, RASSF1C is highly expressed in ESCC tissues. RASSF1A methylation and protein expression were independently associated with ESCC patients' survival. These data indicated that the inactivation of RASSF1A through promoter and exon 1 methylation may play an important role in ESCC carcinogenesis and reactivation of RASSF1A gene may has therapeutic potential and may be used as a prognostic marker for ESCC patients.
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Multiple-beam output of a surface-emitted terahertz-wave parametric oscillator by using a slab MgO:LiNbO? crystal.
Opt Lett
PUBLISHED: 02-25-2014
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A MgO:LiNbO? slab configuration for the surface-emitted terahertz-wave parametric oscillator (TPO) is presented. The pump and the oscillating Stokes beams were totally reflected at the slab surface and propagated zigzaggedly in the slab MgO:LiNbO? crystal. Up to five terahertz beams were emitted perpendicularly to the surface of the crystal. The total output energy of the five THz-wave beams was 3.56 times as large as that obtained from the conventional surface-emitted TPO at the same experimental conditions. The intensity distributions of the THz wave beams were measured, and they were unsymmetrical in the horizontal direction while symmetrical in the vertical direction.
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Desolvation and dehydrogenation of solvated magnesium salts of dodecahydrododecaborate: relationship between structure and thermal decomposition.
Chemistry
PUBLISHED: 02-20-2014
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Attempts to synthesize solvent-free MgB12H12 by heating various solvated forms (H2O, NH3, and CH3OH) of the salt failed because of the competition between desolvation and dehydrogenation. This competition has been studied by thermogravimetric analysis (TGA) and temperature-programmed desorption (TPD). Products were characterized by IR, solution- and solid-state NMR spectroscopy, elemental analysis, and single-crystal or powder X-ray diffraction analysis. For hydrated salts, thermal decomposition proceeded in three stages, loss of water to form first hexahydrated then trihydrated, and finally loss of water and hydrogen to form polyhydroxylated complexes. For partially ammoniated salts, two stages of thermal decomposition were observed as ammonia and hydrogen were released with weight loss first of 14?% and then 5.5?%. Thermal decomposition of methanolated salts proceeded through a single step with a total weight loss of 32?% with the release of methanol, methane, and hydrogen. All the gaseous products of thermal decomposition were characterized by using mass spectrometry. Residual solid materials were characterized by solid-state (11)B magic-angle spinning (MAS)?NMR spectroscopy and X-ray powder diffraction analysis by which the molecular structures of hexahydrated and trihydrated complexes were solved. Both hydrogen and dihydrogen bonds were observed in structures of [Mg(H2O)6B12H12]?6?H2O and [Mg(CH3OH)6B12H12]?6?CH3OH, which were determined by single-crystal X-ray diffraction analysis. The structural factors influencing thermal decomposition behavior are identified and discussed. The dependence of dehydrogenation on the formation of dihydrogen bonds may be an important consideration in the design of solid-state hydrogen storage materials.
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Observation and management of retinal changes related to diving in professional divers.
Chin. Med. J.
PUBLISHED: 02-19-2014
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It is very common for professional divers to have damage on the retinas. Severe retinal lesions can profoundly affect athletes' training efficacy and their daily lives. At present, it is not clear if there is effective preventive action. Thus, in our study, we continuously tracked the ocular changes in athletes and closely monitored the risk factors associated with retinal detachment. Also, we analyzed possible interventions, their associated factors, and efficacies for timely preventions to protect the retina from damage in professional divers.
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Impact of chronic low to moderate alcohol consumption on blood lipid and heart energy profile in acetaldehyde dehydrogenase 2-deficient mice.
Acta Pharmacol. Sin.
PUBLISHED: 02-17-2014
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To investigate the roles of acetaldehyde dehydrogenase 2 (ALDH2), the key enzyme of ethanol metabolism, in chronic low to moderate alcohol consumption-induced heart protective effects in mice.
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Metformin inhibits proliferation and enhances chemosensitivity of intrahepatic cholangiocarcinoma cell lines.
Oncol. Rep.
PUBLISHED: 02-14-2014
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Metformin is an oral anti-hyperglycemic agent of the biguanide family, which is used first-line for type II diabetes with few side-effects. A recent epidemiological study that included 1,828 potential intrahepatic cholangiocarcinoma (ICC) patients showed that metformin use was significantly associated with a 60% reduction in ICC risk in diabetic patients, demonstrating the potential value of metformin in ICC management. In the present study, we firstly showed that metformin exhibited a dose- and time-dependent anti-proliferation effect on ICC cell lines, by mechanisms including apoptosis induction and cell cycle arrest. Metformin targeted the AMPK/mTORC1 pathway in ICC cells. Furthermore, metformin sensitized ICC cells to certain chemotherapeutic agents, such as sorafenib, 5-fluorouracil and As2O3 by targeting the AMPK/mTOR/HIF-1?/MRP1 pathway and ERK. As it is an inexpensive and widely used antidiabetic drug without severe adverse effects, metformin may be a prospective chemotherapeutic agent or a chemosensitizer in future ICC treatment.
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miR-146a G>C polymorphisms and risk of hepatocellular carcinoma in a Chinese population.
Tumour Biol.
PUBLISHED: 02-13-2014
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MicroRNAs (miRNAs) are thought to have a role in cancer development. We investigated the association among miR-146a G>C genetic variations, hepatitis B (HBV), and C (HCV) infection, and risk of hepatocellular carcinoma (HCC). Unconditional logistical regression analysis suggested that the miR-146a GG genotype and G allele carried a 2.10- (95 % confidence interval (CI)=1.03-4.37) and 1.42-fold (95 % CI=1.07-1.92) increased HCC risk, respectively. HBV-positive subjects carrying the miR-146a GG genotype (odds ratio (OR)=2.95, 95 % CI=1.31-6.81) and G allele (OR=1.65, 95 % CI=1.15-2.58) had an increased risk of HCC. However, the miR-146a GG genotype and G allele did not carry a significantly enhanced risk of HCC in either hepatitis-negative or HCV-infected subjects. miR-146a G>C polymorphisms appear to influence susceptibility to HCC, especially in HBV-infected patients.
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Hydrogen peroxide-independent production of ?-alkenes by OleTJE P450 fatty acid decarboxylase.
Biotechnol Biofuels
PUBLISHED: 02-10-2014
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Cytochrome P450 OleTJE from Jeotgalicoccus sp. ATCC 8456, a new member of the CYP152 peroxygenase family, was recently found to catalyze the unusual decarboxylation of long-chain fatty acids to form ?-alkenes using H2O2 as the sole electron and oxygen donor. Because aliphatic ?-alkenes are important chemicals that can be used as biofuels to replace fossil fuels, or for making lubricants, polymers and detergents, studies on OleTJE fatty acid decarboxylase are significant and may lead to commercial production of biogenic ?-alkenes in the future, which are renewable and more environmentally friendly than petroleum-derived equivalents.
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Effectiveness of recombinant protein AlnA in enhancing the extractability of polychlorinated biphenyls from contaminated soils.
J. Hazard. Mater.
PUBLISHED: 02-07-2014
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One of the major limitations in bioremediation of polychlorinated biphenyls (PCBs) in contaminated soils is their low water solubility and high adsorbability. In the present study, effectiveness of recombinant protein AlnA as a biosurfactant in increasing extractability of PCBs was first investigated. The AlnA surface tension measurements allowed for determination of the minimum value of 37.89mN/m with critical micelle concentration of 1.07g/L. The solubilization of PCBs and desorption experiments were performed. It was observed that AlnA at 20?g/mL could enhance solubility of selected crystal PCBs varying from 1.87 to 6.12 folds and it is easier to recover PCBs from contaminated soils compared with Tween-80 and cyclodextrin. Pot experiments indicated AlnA elevated 1.4-2.1-fold PCBs accumulation in roots by Alfalfa. The homology modeling and docking revealed PCBs congeners had different interactions with AlnA and higher-chlorinated PCBs possessed higher binding affinity. Results showed AlnA had considerable application potential in remediation of PCBs pollution.
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Quantum molecular dynamics study of warm dense iron.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 02-06-2014
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The equation of state, the self-diffusion coefficient and viscosity of fluid iron in the warm dense regime at densities from 12.5 to 25.0g/cm^{3}, and temperatures from 0.5 to 15.0 eV have been calculated via quantum molecular dynamics simulations. The principal Hugoniot is in good agreement with nuclear explosive experiments up to ?50Mbar but predicts lower pressures compared with high intensity laser results. The self-diffusion coefficient and viscosity have been simulated and have been compared with the one-component plasma model. The Stokes-Einstein relationship, defined by connections between the viscosity and the self-diffusion coefficient, has been determined and has been found to be fairly well described by classical predictions.
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Association between carcinoembryonic antigen levels and the applied value of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in post-operative recurrent and metastatic colorectal cancer.
Oncol Lett
PUBLISHED: 02-04-2014
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Positron emission tomography (PET) using (18)F-fluorodeoxyglucose has been widely used for analyzing cellular metabolism. The present study aimed to evaluate the association between the diagnostic value of PET/computed tomography (CT) in patients with post-operative recurrent and metastatic colorectal cancer (CRC), and the different levels of carcinoembryonic antigen (CEA). A total of 105 suspected recurrent and metastatic CRC patients (67 males and 38 females; mean age, 48.5 years) were included in this retrospective study. All the patients underwent PET/CT examination. The differences in the PET/CT diagnostic values of CEA-positive and -negative patients with recurrent CRC following surgery were retrospectively analyzed and compared. Among the 105 CRC patients, 87 exhibited recurrence and metastasis, as confirmed by histopathological diagnosis or clinical follow-up data. By contrast, the PET/CT examination results revealed that 85 cases were true positives (a false positive foci was diagnosed in one of the patients), 18 were true negatives and 2 were false negatives. Correspondingly, the sensitivity and degree of accuracy were 97.7 and 97.1%, respectively. The detection rates of PET/CT for the recurrence and metastases were 85.3% in the CEA-positive group and 75.7% in the CEA-negative group. No significant differences were observed between the two groups. Overall, CEA levels do not help improve the detection rate of PET/CT in the recurrence and metastasis of CRC. PET/CT imaging has a high sensitivity and degree of accuracy in detecting recurrence and metastasis following CRC surgery. Therefore, this method is ideal for monitoring relapsed and metastatic foci of post-operative colon cancer cases.
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Relationship between spin ordering, entropy, and anomalous lattice variation in Mn3Sn(1-?)Si(?)C(1-?) compounds.
Inorg Chem
PUBLISHED: 02-03-2014
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The crystal and magnetic structures of antiperovskite compounds Mn3SnC, Mn3Sn0.95C0.9, and Mn3Sn0.93Si0.07C0.94 were studied as a function of temperature and magnetic field by neutron powder diffraction. For Mn3SnC, the magnetic field induces a dramatic variation of antiferromagnetic moment and lattice parameter. Because of this spin-lattice coupling, the "square" antiferromagnetic (AFM) structure plays a key role in inducing a negative thermal expansion in the material. Moreover, the thermal expansion parameter is closely related to the rate of change of the AFM moment, which can be controlled by introducing vacancies or by doping. The variations of the AFM moment and lattice parameter in Mn3SnC with magnetic field make it possible to use the tunable properties for technical applications.
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Silencing of FGF-21 expression promotes hepatic gluconeogenesis and glycogenolysis by regulation of the STAT3-SOCS3 signal.
FEBS J.
PUBLISHED: 01-29-2014
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Insulin resistance is a metabolic disorder associated with type 2 diabetes. Recent reports have shown that fibroblast growth factor-21 (FGF-21) plays an important role in the progression of insulin resistance. However, the biochemical and molecular mechanisms by which changes in FGF-21 activation result in changes in the rates of hepatic gluconeogenesis and glycogenolysis remain to be elucidated. In this study, we developed adenovirus-mediated shRNA against FGF-21 to inhibit FGF-21 expression in ApoE knockout mice. Using this mouse model, we determined the effects of FGF-21 knockdown in vivo on hepatic glucose production, gluconeogenesis and glycogenolysis, and their relationship with the signal transducer and activator of transcription 3 (STAT3)/suppressor of cytokine signaling 3 (SOCS3) signal pathways. We show that liver-specific knockdown of FGF-21 in high-fat diet-fed ApoE knockout mice resulted in a 39% increase in glycogenolysis and a 75% increase in gluconeogenesis, accompanied by increased hepatic expression of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase. Furthermore, FGF-21 knockdown decreased phosphorylation of STAT3 and SOCS3 expression in high-fat diet-fed mice. Our data suggest that hepatic FGF-21 knockdown increases gluconeogenesis and glycogenolysis by activation of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase via the STAT3/SOCS3 pathway, ultimately leading to exacerbation of hepatic insulin resistance.
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Activated Wnt signaling induces myofibroblast differentiation of mesenchymal stem cells, contributing to pulmonary fibrosis.
Int. J. Mol. Med.
PUBLISHED: 01-29-2014
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Acute lung injury may lead to fibrogenesis. However, no treatment is currently available. This study was conducted to determine the effects of bone marrow-derived mesenchymal stem cells (MSCs) in a model of HCl-induced acute lung injury in Sprague-Dawley (SD) rats. Stromal cell-derived factor (SDF)-1 and its receptor CXC chemokine receptor (CXCR)4 have been shown to participate in mobilizing MSCs. Adenovirus carrying the CXCR4 gene was used to transfect MSCs in order to increase the engraftment numbers of MSCs at injured sites. Histological examination data demonstrated that the engraftment of MSCs did not attenuate lung injury and pulmonary fibrosis. The results showed that engraftment of MSCs almost differentiated into myofibroblasts, but rarely differentiated into lung epithelial cells. Additionally, it was demonstrated that activated canonical Wnt/?-catenin signaling in injured lung tissue regulated the myofibroblast differentiation of MSCs in vivo. The in vitro study results demonstrated that activation of the Wnt/?-catenin signaling stimulated MSCs to express myofibroblast markers; however, this process was attenuated by Wnt antagonist DKK1. Therefore, the results demonstrated that the aberrant activation of Wnt signaling induces the myofibroblast differentiation of engrafted MSCs, thus contributing to pulmonary fibrosis following lung injury.
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Low testosterone levels in women with diminished ovarian reserve impair embryo implantation rate: a retrospective case-control study.
J. Assist. Reprod. Genet.
PUBLISHED: 01-28-2014
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To investigate the association of basal testosterone (T) levels with the outcome of in vitro fertilization (IVF) in women with diminished ovarian reserve (DOR).
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Transarterial chemoembolization combined with sorafenib for advanced hepatocellular carcinoma.
Oncol Lett
PUBLISHED: 01-19-2014
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Sorafenib has been demonstrated to improve survival rate in patients with advanced hepatocellular carcinoma (HCC); however, the survival benefit remains modest and the response rates remain poor. Transarterial chemoembolization (TACE) may be used for the treatment of advanced HCC with well-preserved liver function and has a high local tumor control rate. We hypothesized that patients with advanced HCC may benefit from the combination of sorafenib with TACE. A retrospective study was conducted involving patients with advanced HCC, who had received at least one TACE session. Patients subsequently received 400 mg sorafenib twice per day and were monitored monthly. A dose reduction from 400 to 200 mg of sorafenib twice per day was permitted. The overall survival and side effects were subsequently followed up. In total, 38 patients were included from April 1st, 2009 to March 31st, 2012. All patients were treated with sorafenib after TACE was performed. As of March 31st, 2013, seven patients remained on sorafenib, and were censored at that time point. The median overall survival time was 12 months (95% confidence interval, 6.3-17.7 months). The sorafenib dose was reduced temporarily in 32 patients (84.2%). The most common toxicities were dermatological adverse effects (94.7%), diarrhea (63.2%) and alopecia (26.3%). The survival benefit of sorafenib combined with TACE for advanced HCC is promising, with no intolerable adverse events, provided that dose adjustment is permitted.
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Radioactive self-expanding stents give superior palliation in patients with unresectable cancer of the esophagus but should be used with caution if they have had prior radiotherapy.
Ann. Thorac. Surg.
PUBLISHED: 01-13-2014
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Self-expandable stents loaded with 125I (iodine 125) seeds may combine the advantages of the immediate relief of esophageal dysphagia with stent placement and radiation therapy with brachytherapy. We compared the self-expanding irradiation stent with a conventional self-expandable covered stent in patients with malignant dysphagia due to recurrent esophageal cancer.
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Association of XRCC1 polymorphisms with thyroid cancer risk.
Tumour Biol.
PUBLISHED: 01-06-2014
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Due to the important role in the DNA repair pathways, numerous studies have been carried out to explore the relationship between the polymorphisms in the X-ray repair cross-complementing group 1 (XRCC1) gene and thyroid cancer risk. But previous reports have produced conflicting results. Thus, we performed an updated comprehensive meta-analysis to better investigate the association of the XRCC1 polymorphisms with thyroid cancer risk. There were a total of nine studies included with 1,621 cases and 3,669 controls examining the effects of the XRCC1 Arg280His, Arg399Gln, and Arg194Trp polymorphisms on the susceptibility of thyroid cancer. In our study, the XRCC1 Arg280His polymorphism was found to be associated with an increased thyroid cancer risk in the Caucasian population [allelic contrast: odds ratio (OR)?=?1.38, 95% CI?=?1.05-1.80, P(Z)?=?0.02, P(Q)?=?0.61; dominant model: OR?=?1.43, 95% CI?=?1.08-1.89, P(Z)?=?0.01, P(Q)?=?0.57]. The Arg399Gln polymorphism was associated with a significant decreased risk [allelic contrast: OR?=?0.73, 95% CI?=?0.59-0.92, P(Z)?=?0.006, P(Q)?=?0.31; dominant model: OR?=?0.73, 95% CI?=?0.55-0.97, P(Z)?=?0.03, P(Q)?=?0.33; recessive model: OR?=?0.56, 95% CI?=?0.34-0.93, P(Z)?=?0.02, P(Q)?=?0.59], while the Arg194Trp SNP conferred an increased risk for thyroid cancer in the mixed populations [allelic contrast: OR?=?1.49, 95% CI?=?1.02-2.17, P(Z)?=?0.04]. To conclude, the present meta-analysis demonstrated that the polymorphisms in the XRCC1 gene may be associated with developing of thyroid cancer.
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Comparative analysis of barium titanate thin films dry etching using inductively coupled plasmas by different fluorine-based mixture gas.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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In this work, the inductively coupled plasma etching technique was applied to etch the barium titanate thin film. A comparative study of etch characteristics of the barium titanate thin film has been investigated in fluorine-based (CF4/O2, C4F8/O2 and SF6/O2) plasmas. The etch rates were measured using focused ion beam in order to ensure the accuracy of measurement. The surface morphology of etched barium titanate thin film was characterized by atomic force microscope. The chemical state of the etched surfaces was investigated by X-ray photoelectron spectroscopy. According to the experimental result, we monitored that a higher barium titanate thin film etch rate was achieved with SF6/O2 due to minimum amount of necessary ion energy and its higher volatility of etching byproducts as compared with CF4/O2 and C4F8/O2. Low-volatile C-F compound etching byproducts from C4F8/O2 were observed on the etched surface and resulted in the reduction of etch rate. As a result, the barium titanate films can be effectively etched by the plasma with the composition of SF6/O2, which has an etch rate of over than 46.7 nm/min at RF power/inductively coupled plasma (ICP) power of 150/1,000 W under gas pressure of 7.5 mTorr with a better surface morphology.
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Effect of sulfur hexafluoride gas and post-annealing treatment for inductively coupled plasma etched barium titanate thin films.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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Aerosol deposition- (AD) derived barium titanate (BTO) micropatterns are etched via SF6/O2/Ar plasmas using inductively coupled plasma (ICP) etching technology. The reaction mechanisms of the sulfur hexafluoride on BTO thin films and the effects of annealing treatment are verified through X-ray photoelectron spectroscopy (XPS) analysis, which confirms the accumulation of reaction products on the etched surface due to the low volatility of the reaction products, such as Ba and Ti fluorides, and these residues could be completely removed by the post-annealing treatment. The exact peak positions and chemicals shifts of Ba 3d, Ti 2p, O 1 s, and F 1 s are deduced by fitting the XPS narrow-scan spectra on as-deposited, etched, and post-annealed BTO surfaces. Compared to the as-deposited BTOs, the etched Ba 3d 5/2 , Ba 3d 3/2 , Ti 2p 3/2 , Ti 2p 1/2 , and O 1 s peaks shift towards higher binding energy regions by amounts of 0.55, 0.45, 0.4, 0.35, and 0.85 eV, respectively. A comparison of the as-deposited film with the post-annealed film after etching revealed that there are no significant differences in the fitted XPS narrow-scan spectra except for the slight chemical shift in the O 1 s peak due to the oxygen vacancy compensation in O2-excessive atmosphere. It is inferred that the electrical properties of the etched BTO film can be restored by post-annealing treatment after the etching process. Moreover, the relative permittivity and loss tangent of the post-annealed BTO thin films are remarkably improved by 232% and 2,695%, respectively.
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Effects of starting powder and thermal treatment on the aerosol deposited BaTiO3 thin films toward less leakage currents.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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To prepare high-density integrated capacitors with low leakage currents, 0.2-?m-thick BaTiO3 thin films were successfully deposited on integrated semiconductor substrates at room temperature by the aerosol deposition (AD) method. In this study, the effects of starting powder size were considered in an effort to remove macroscopic defects. A surface morphology of 25.3 nm and an interface roughness of less than 50 nm were obtained using BT-03B starting powder. The nano-crystalline thin films achieved after deposition were annealed at various temperatures to promote crystallization and densification. Moreover, the influence of rapid thermal annealing process on the surface morphology and crystal growth was evaluated. As the annealing temperature increased from room temperature to 650°C, the root mean square (RMS) roughness decreased from 25.3 to 14.3 nm. However, the surface was transformed into rough performance at 750°C, which agreed well with the surface microstructure trend. Moreover, the crystal growth also reveals the changes in surface morphology via surface energy analysis.
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Hyperbaric oxygen preconditioning promotes neovascularization of transplanted skin flaps in rats.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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To determine whether Hyperbaric oxygen preconditioning (HBO-PC) promotes neovascularization by increasing Stromal cell derived factor-1 (SDF-1) and CXC chemokine receptor 4 (CXCR4) in transplanted skin flaps of rats. The epigastric pedicle skin flap was established in a rat model. Rats were randomly assigned to the following five groups: 1) sham-operated group (SH); 2) ischemia followed by reperfusion 3 days postoperatively group (IR3d); 3) ischemia followed by reperfusion 5 days postoperatively group (IR5d); 4) hyperbaric oxygen preconditioning and ischemia followed by reperfusion 3 days postoperatively group (HBO-PC3d); and 5) hyperbaric oxygen preconditioning and ischemia followed by reperfusion 5 days postoperatively group(HBO-PC5d). For the groups receiving HBO-PC, animals underwent 1 hour of HBO at 2.0 ATA in 100% O2 twice per day for 3 days consecutively prior to surgery. After perfusion, Laser Doppler perfusion imaging (LDPI) was performed, and skin flap tissue samples were harvested for histological evaluation and western blot analysis. Perfusion was significantly improved in the HBO-PC groups compared with the IR groups on postoperative 3 and 5. Microvessel density (MVD) was significantly increased by HBO-PC compared with IR groups postoperatively. Western blot analysis revealed that SDF-1 and CXCR4 expression in the HBO-PC groups was significantly increased compared with IR groups. HBO-PC promoted neovascularization via increasing expression levels of SDF-1 and CXCR4 in transplanted skin flaps of rats.
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Evaluation of the role of dynamic contrast-enhanced MR imaging for patients with BI-RADS 3-4 microcalcifications.
PLoS ONE
PUBLISHED: 01-01-2014
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The purpose of study was to prospectively evaluate the diagnostic performance of dynamic contrast-enhanced MR imaging in the differentiation of malignant lesions from benign ones in patients with BI-RADS 3-4 microcalcifications detected by mammography.
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Earlier-season vegetation has greater temperature sensitivity of spring phenology in northern hemisphere.
PLoS ONE
PUBLISHED: 01-01-2014
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In recent decades, satellite-derived start of vegetation growing season (SOS) has advanced in many northern temperate and boreal regions. Both the magnitude of temperature increase and the sensitivity of the greenness phenology to temperature-the phenological change per unit temperature-can contribute the advancement. To determine the temperature-sensitivity, we examined the satellite-derived SOS and the potentially effective pre-season temperature (T eff) from 1982 to 2008 for vegetated land between 30°N and 80°N. Earlier season vegetation types, i.e., the vegetation types with earlier SOSmean (mean SOS for 1982-2008), showed greater advancement of SOS during 1982-2008. The advancing rate of SOS against year was also greater in the vegetation with earlier SOSmean even the T eff increase was the same. These results suggest that the spring phenology of vegetation may have high temperature sensitivity in a warmer area. Therefore it is important to consider temperature-sensitivity in assessing broad-scale phenological responses to climatic warming. Further studies are needed to explore the mechanisms and ecological consequences of the temperature-sensitivity of start of growing season in a warming climate.
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Efficacy of topical calcineurin inhibitors in psoriasis.
J Cutan Med Surg
PUBLISHED: 01-01-2014
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Topical calcineurin inhibitors (tacrolimus and pimecrolimus) are indicated for the treatment of atopic dermatitis but have also been studied in the treatment of psoriasis.
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Comparative analysis of nano-scale structural and electrical properties in AlGaN/GaN high electron mobility transistors on SiC and sapphire substrates.
J Nanosci Nanotechnol
PUBLISHED: 11-20-2013
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A comparison of AIGaN/GaN HEMTs fabricated on both 4-in SiC and sapphire substrates was performed. Due to the high crystalline quality with one order lower dislocation density of GaN on a SiC substrate, a better two-dimensional electron gas (2DEG) mobility with high values of drain current density (780 mA/mm) and a better extrinsic transconductance (240 mS/mm) were observed. We demonstrate GaN-on-SiC HEMTs with a periphery gate width of 200 microm, exhibiting a unity-gain cut-off frequency (f(T)) = 29.6 GHz, a maximum frequency of oscillation (f(MAX)) = 63.2 GHz, and an output power density of 6.4 W/mm with a 55% power added efficiency (PAE) at 10 GHz. A surface roughness of 0.828 nm and 1.025 nm and an X-ray diffraction (XRD) GaN (0002) full-width at half-maximum (FWHM) of 120 s and 919 s were measured for the SiC and sapphire-based AIGaN/GaN HEMTs, respectively. The SiC substrate has been shown to be an optimal solution for fabricating HEMTs for X-band high-power applications, which require excellent performances.
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Extracavity pumped BaWO4 anti-Stokes Raman laser.
Opt Express
PUBLISHED: 11-13-2013
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The characteristics of a barium tungstate (BaWO(4)) anti-Stokes Raman laser at 968 nm are studied theoretically and experimentally. The BaWO(4) Raman resonator is pumped by a Q-switched Nd:YAG laser at 1064 nm with its axis tilted from the pumping laser axis. The non-collinear phase matching for the generation of the first anti-Stokes wave in the same BaWO(4) crystal is achieved. The output energy, temporal and spectral informations are investigated. At a pumping laser energy of 128 mJ, the anti-Stokes laser energy obtained is 2.2 mJ. The second Stokes radiation at 1324 nm as well as the first and the third Stokes waves at 1180 nm and 1509 nm is also generated at the same time. The maximum total Stokes energy output is 42.5 mJ. In the theory, the anti-Stokes laser intensity expression as a function of the pumping and the first Stokes laser intensities for the extracavity anti-Stokes Raman laser is deduced. The properties of the anti-Stokes Raman laser are simulated theoretically by solving the rate equations of the extracavity Raman laser and using the derived expression. The theoretical results are in good agreement with the experimental results.
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[Effect of calcium on medium alkalinization induced by salicylic acid in Salvia miltiorrhiza suspension cultures].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 11-08-2013
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We studied medium alkalinization in Salvia miltiorrhiza suspension cultures treated with salicylic acid and the effect of Ca2+ in this process through application of calcium channel antagonists (Verapamil, LaCl3, LiCl, 2-APB) and ionophore A23187. The results show that salicylic acid could induce significant medium alkalinization in S. miltiorrhiza culture. Verapamil and LaCl3 or LiCl and 2-APB, two different groups of calcium channel antagonist, significantly inhibited the medium alkalinization induced by salicylic acid. However, the suppression effect of verapamil or LaCl3 on medium alkalinization induced by salicylic acid was higher than that of LiCl or 2-APB. When two types of calcium channel inhibitor (LaCl3 and 2-APB) were used together, the medium alkalinization induced by salicylic acid was completely suppressed and even reduced the pH in medium. On the other hand, A23187 could promote the medium alkalinization. Based on the results above, we speculated that salicylic acid could induce significant medium alkalinization in S. miltiorrhiza culture, depending on the calcium from both extracell and intracell. Moreover, calcium from extracell plays a more dominant role in this process. Reveal of relationship in this research between Ca2+ and medium alkalinization can provide theory evidence for mechanism of the plant secondary metabolism.
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Identification of a novel peptide that blocks basic fibroblast growth factor-mediated cell proliferation.
Oncotarget
PUBLISHED: 10-22-2013
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Basic fibroblast growth factor (bFGF) has been implicated in tumor growth via interactions with its receptors (FGFRs) on the cell surface and therefore, bFGF/FGFRs are considered essential targets for cancer therapy. Herein, a consensus heptapeptide (LSPPRYP) was identified for the first time from a phage display heptapeptide library after three sequential rounds of biopanning against FGFR-expressing cells with competitive displacement of phage by bFGF, followed by subtraction of non-specific binding by FGFR-deficient cells. Phage bearing LSPPRYP showed high levels of binding to Balb/c 3T3 cells expressing high-affinity bFGF-binding FGFR (bFGFR), but not to the cells that do not express bFGFR (Cos-7), or express a very low affinity bFGFR (HaCat). The selected-phage-derived peptide synthesized by solid phase method using a rapid and practical Fmoc strategy was found to specifically compete with bFGF for binding to its receptors, inhibit bFGF-stimulated cell proliferation by inducing cell cycle arrest, and block bFGF-induced activation of Erk1 and Erk2 kinase in B16-F10 melanoma cells. Importantly, treatment of melanoma-bearing mice with the synthetic peptide significantly suppressed tumor growth. The results demonstrate a strong anticancer activity of the isolated bFGFR-binding peptide (and its future derivatives), which may have great potential for cancer therapy.
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A brain-computer interface controlled mail client.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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In this paper, we propose a brain-computer interface (BCI) based mail client. This system is controlled by hybrid features extracted from scalp-recorded electroencephalographic (EEG). We emulate the computer mouse by the motor imagery-based mu rhythm and the P300 potential. Furthermore, an adaptive P300 speller is included to provide text input function. With this BCI mail client, users can receive, read, write mails, as well as attach files in mail writing. The system has been tested on 3 subjects. Experimental results show that mail communication with this system is feasible.
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