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Find video protocols related to scientific articles indexed in Pubmed.
Tuning Polymorphism and Orientation in Organic Semiconductor Thin Films via Post-deposition Processing.
J. Am. Chem. Soc.
PUBLISHED: 10-24-2014
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Though both the crystal structure and molecular orientation of organic semiconductors are known to impact charge transport in thin-film devices, separately accessing different polymorphs and varying the out-of-plane molecular orientation is challenging, typically requiring stringent control over film deposition conditions, film thickness, and substrate chemistry. Here we demonstrate independent tuning of the crystalline polymorph and molecular orientation in thin films of contorted hexabenzocoronene, c-HBC, during post-deposition processing without the need to adjust deposition conditions. Three polymorphs are observed, two of which have not been previously reported. Using our ability to independently tune the crystal structure and out-of-plane molecular orientation in thin films of c-HBC, we have decoupled and evaluated the effects that molecular packing and orientation have on device performance in thin-film transistors (TFTs). In the case of TFTs comprising c-HBC, polymorphism and molecular orientation are equally important; independently changing either one affects the field-effect mobility by an order of magnitude.
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Efficient organic solar cells with helical perylene diimide electron acceptors.
J. Am. Chem. Soc.
PUBLISHED: 10-14-2014
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We report an efficiency of 6.1% for a solution-processed non-fullerene solar cell using a helical perylene diimide (PDI) dimer as the electron acceptor. Femtosecond transient absorption spectroscopy revealed both electron and hole transfer processes at the donor-acceptor interfaces, indicating that charge carriers are created from photogenerated excitons in both the electron donor and acceptor phases. Light-intensity-dependent current-voltage measurements suggested different recombination rates under short-circuit and open-circuit conditions.
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Structure-property relationship study of substitution effects on isoindigo-based model compounds as electron donors in organic solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 08-12-2014
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We designed and synthesized a series of isoindigo-based derivatives to investigate how chemical structure modification at both the 6,6'- and 5,5'-positions of the core with electron-rich and electron-poor moieties affect photophysical and redox properties as well as their solid-state organization. Our studies reveal that 6,6'-substitution on the isoindigo core results in a stronger intramolecular charge transfer band due to strong electronic coupling between the 6,6'-substituent and the core, whereas 5,5'-substitution induces a weaker CT band that is more sensitive to the electronic nature of the substituents. In the solid state, 6,6'-derivatives generally form J-aggregates, whereas 5,5'-derivatives form H-aggregates. With only two branched ethylhexyl side chains, the 6,6'-derivatives form organized lamellar structures in the solid state. The incorporation of electron-rich benzothiophene, BT, substituents further enhances ordering, likely because of strong intermolecular donor-acceptor interactions between the BT substituent and the electron-poor isoindigo core on neighboring compounds. Collectively, the enhanced photophysical properties and solid-state organization of the 6,6'-benzothiophene substituted isoindigo derivative compared to the other isoindigo derivatives examined in this study resulted in solar cells with higher power conversion efficiencies when blended with a fullerene derivative.
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The application of McBurney's single-incision laparoscopic colectomy alleviates the response of patients to postoperative wound pain.
J Laparoendosc Adv Surg Tech A
PUBLISHED: 07-31-2014
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Single-incision laparoscopic colectomy (SILC) is one of several promising operation choices. Our previous study demonstrated that SILC with a self-made glove-port system both improves the feasibility of SILC and decreases the cost expense of surgery. Because the incision site for SILC could be made at either the umbilicus or McBurney's point, we are interested in whether the incision site affects the outcomes of patients, which is a less explored topic. The purpose of this study is not only to show the results of SILC with a self-made glove-port system for supporting its feasibility, but also to compare the short-term surgical outcomes between SILC with the incision made at the umbilicus and at McBurney's point.
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Alpinia oxyphylla Miquel fruit extract activates MAPK-mediated signaling of PAs and MMP2/9 to induce Schwann cell migration and nerve regeneration.
Int J Artif Organs
PUBLISHED: 06-15-2014
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This study investigates the molecular mechanisms by which Alpiniae oxyphyllae fructus (AOF) promotes neuron regeneration.
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Cardiac hypertrophy-related pathways in obesity.
Chin J Physiol
PUBLISHED: 05-16-2014
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Obesity is often associated with the development of cardiac hypertrophy but the hypertrophyrelated pathways in obesity remain unknown. The purpose of this study was to evaluate cardiac hypertrophy-related markers, atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), tumor necrosis factor-alpha (TNF?) and hypertrophy-related pathways, interleukin (IL)-6-STAT3, IL-6-MEK5-ERK5 and calcineurin-nuclear factor of activated T-cells (NFAT)3 in the excised hearts from obese rats. Twelve obese Zucker rats were studied at 5-6 months of age and twelve age-matched lean Zucker rats served as the control group. The cardiac characteristics, myocardial architecture, ANP, BNP, TNF? levels, IL-6, STAT3, p-STAT3, MEK5, ERK-5, p-ERK-5, calcineurin and NFAT3 in the left ventricle from the rats were measured by heart weight index, echocardiography, vertical cross section, histological analysis, reverse transcription polymerase chain reaction and western blotting. Compared with the lean control, the whole heart weight, the left ventricule weight, the ratio of the whole heart weight to tibia length, echocardiographic interventricular septum, left ventricular posterior wall thickness, myocardial morphological changes and systolic blood pressure were found to increase in the obese rats. The protein levels of ANP, BNP, TNF?, IL-6, STAT3, p-STAT3, MEK-5, ERK-5, p-ERK 5, calcineurin and NFAT3 were also significantly increased in the hearts of the obese rats. The results showed that the hypertrophy-related markers, ANP, BNP and TNF?, the hypertrophy-related pathways IL-6-STAT3 and IL-6-MEK5-ERK5, and the calcineurin-NFAT3 hypertrophy-related pathways were more active in obese Zucker rats, which may provide possible hypertrophic mechanisms for developing cardiac hypertrophy and pathological changes in obesity.
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Psychometric properties of the finding a balance scale for family caregivers of elders with dementia in Taiwan.
Res Nurs Health
PUBLISHED: 04-29-2014
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The Finding a Balance Scale, designed to measure the degree to which caregivers can balance the competing demands of caregiving and other priorities, assists health care providers in understanding the process of family caregiving. The aim of this study was to examine the scale's psychometric properties and determine an appropriate cutoff score for identifying caregivers at high risk for poor caregiving consequences. We found adequate reliabilities and appropriate validities in a convenience sample of 197 family caregivers of elders with dementia in Taiwan. The optimal cutoff was also determined. The validated Finding a Balance Scale provides an assessment tool to explore the competing responsibilities, conditions, and difficulties for family caregivers of elders with dementia in Taiwan.
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Effect of ozone exposure on the electrical characteristics of high-purity, large-diameter semiconducting carbon nanotubes.
Phys Chem Chem Phys
PUBLISHED: 04-25-2014
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In this study, we have elucidated the interactions between ozone and carbon nanotubes by monitoring the characteristics of field-effect transistors based on polymer-sorted, large-diameter semiconducting carbon nanotubes. The drain-source current of these transistors initially increases with ozone exposure and then it progressively decreases with increasing exposure beyond 3 min. This non-monotonic dependence of the drain-source current can be ascribed to two competing processes. At short ozone exposure, p-doping of carbon nanotubes dominates; the drain-source current thus increases as a result of increasing hole concentration. This effect is most evidenced in a progressive threshold voltage shift towards positive voltages with increasing exposure to ozone. At extended ozone exposure, chemical oxidation of carbon nanotubes instead dominates. The drain-source current decreases as a result of decreasing hole mobility. This effect manifests itself in a monotonic decrease in the mobility of these devices as a function of ozone exposure.
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Herbal supplement attenuation of cardiac fibrosis in rats with CCl?-induced liver cirrhosis.
Chin J Physiol
PUBLISHED: 03-14-2014
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Previously we found carbon tetrachloride (CCl?) induced cirrhosis associated cardiac hypertrophy and apoptosis. The purpose of this study is to determine whether further CCl? treatment would induce cardiac cell fibrosis. The cardiac tissues were analyzed by H&E. histological staining, Trichrome Masson staining and Western blotting. The results showed that the CCl?-treated-only group exhibits more trichrome staining, meaning that more fibrosis is present. Moreover, CCl? could further induce cardiac-fibrosis via TGF-?-p-Smad2/3-CTGF pathway. However, our data showed that the CCl?- indcued cardiac abnormalities were attenuated by Ocimum gratissimum extract (OGE) and silymarin co- treatments. In conclusion, our results indicated that the OGE and silymarin may be a potential traditional herb for the protection of cardiac tissues from the CCl4 induced cirrhosis associated cardiac fibrosis through modulating the TGF-? signaling pathway.
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Reduction of TLR4 mRNA stability and protein expressions through inhibiting cytoplasmic translocation of HuR transcription factor by E? and/or ER? in LPS-treated H9c2 cardiomyoblast cells.
Chin J Physiol
PUBLISHED: 03-14-2014
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Our previous results have indicated that Akt mediates 17?-estradiol (E?) and/or estrogen receptor ? (ER?) to inhibit lipopolysaccharide (LPS)-induced JNK activity, tumor necrosis factor ? (TNF?) protein expression, and exhibits cardioprotective effects. Toll-like receptor 4 (TLR4) mRNAs often contain AU-rich elements (AREs) in their 3'-untranslated regions (3'UTR) which have a high affinity for RNA-binding proteins. It is not known whether E? and ER? affect TLR4 mRNA stability and TLR4 protein expression through regulating the RNA-binding proteins, human antigen R (HuR), tristetraprolin (TTP) and AU-binding factor 1 (AUF-1) in myocardial cells. Therefore, we investigated if the LPS in- duces these RNA-binding proteins to regulate TLR4 mRNAs of cardiomyocytes, and whether the E?/ER? reduces the TLR4 mRNA stability induced by LPS through the inhibition of RNA-binding protein expression. Using a doxycycline (Dox)-induced Tet-On ER? H9c2 myocardic cell model, we also aimed to identify whether E? and/or ER? regulate LPS-induced TLR4 mRNA stability. The results of Western blotting and reverse transcription-PCR assays demonstrated that LPS significantly in- creased the level of cytoplasmic HuR protein and the stability of TLR4 mRNA, and farther induced TLR4 protein expression in H9c2 cells, an effect mediated through the JNK pathway. Interestingly, E? and/or ER? decreased the cytoplasmic HuR protein level and TLR4 mRNA stability, and farther decreased the level of TLR4 protein induced by LPS in H9c2 cardiomyoblast cells. Therefore, LPS triggered HuR expression which led to enhanced TLR4 mRNA and upregulated TLR4 expression through JNK1/2 in myocardial cells.
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Protective effect of salidroside on cardiac apoptosis in mice with chronic intermittent hypoxia.
Int. J. Cardiol.
PUBLISHED: 03-13-2014
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The goal of this study is to determine if salidroside has protective effects on hypoxia-induced cardiac widely dispersed apoptosis in mice with severe sleep apnea model.
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Resistance to irinotecan (CPT-11) activates epidermal growth factor receptor/nuclear factor kappa B and increases cellular metastasis and autophagy in LoVo colon cancer cells.
Cancer Lett.
PUBLISHED: 03-13-2014
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Chemotherapy is usually applied to treat colon cancer but leads to chemoresistance, and increased metastasis and invasion. The main focus of this study is to observe effects of resistance to irinotecan (CPT-11) on metastasis, invasion and autophagy in CPT-11 resistant (CPT-11-R) LoVo colon cancer cells. CPT-11, a topoisomerase I inhibitor and a first-line chemotherapeutic drug, is used to treat colon cancer. CPT-11-R cells were constructed in a step-wise fashion with increasing CPT-11 doses. The CPT-11-R strain had a significantly lower expression of Wnt/?-catenin pathway, but induced an EGFR/IKK?/?/NF-?B pathway with elevated cell cycle, metastasis and basal autophagy.
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Galectin-1 Accelerates Wound Healing by Regulating the Neuropilin-1/Smad3/NOX4 Pathway and ROS Production in Myofibroblasts.
J. Invest. Dermatol.
PUBLISHED: 03-12-2014
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Myofibroblasts have a key role in wound healing by secreting growth factors and chemoattractants to create new substrates and proteins in the extracellular matrix. We have found that galectin-1, a ?-galactose-binding lectin involved in many physiological functions, induces myofibroblast activation; however, the mechanism remains unclear. Here, we reveal that galectin-1-null (Lgals1(-/-)) mice exhibited a delayed cutaneous wound healing response. Galectin-1 induced myofibroblast activation, migration, and proliferation by triggering intracellular reactive oxygen species (ROS) production. A ROS-producing protein, NADPH oxidase 4 (NOX4), was upregulated by galectin-1 through the neuropilin-1/Smad3 signaling pathway in myofibroblasts. Subcutaneous injection of galectin-1 into wound areas accelerated the healing of general and pathological (streptozotocin-induced diabetes mellitus) wounds and decreased the mortality of diabetic mice with skin wounds. These findings indicate that galectin-1 is a key regulator of wound repair that has therapeutic potential for pathological or imperfect wound healing.Journal of Investigative Dermatology advance online publication, 14 August 2014; doi:10.1038/jid.2014.288.
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Casein kinase 1 epsilon expression predicts poorer prognosis in low T-stage oral cancer patients.
Int J Mol Sci
PUBLISHED: 02-13-2014
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Casein kinase 1 is a group of ubiquitous serine/threonine kinases that are involved in normal cellular functions and several pathological conditions, such as DNA repair, cell cycle progression, cytokinesis, differentiation, and apoptosis. Recent studies have indicated that casein kinase 1-epsilon (CK1?) and casein kinase 1-delta (CK1?) expression has a role in human cancers. We investigated the associations between CK1? and CK1? expression and the clinical parameters of oral cancer using immunohistochemical study methods on oral squamous cell carcinoma specimens. The results of our immunohistochemical analysis showed that the loss of CK1? expression was greatly associated with a poor four-year survival rate in oral cancer patients (p = 0.002). A Kaplan-Meier analysis showed that patients who had a loss of CK1? expression had a considerably poorer overall survival rate than patients who had positive CK1? expressions (p = 0.022). A univariate analysis revealed that patients who had a loss of CK1? expression had considerably poorer overall survival (OS) than patients who had positive expression (p = 0.024, hazard ratio (HR) = 1.7). In conclusion, our data indicated that the loss of cytoplasmic CK1? expression is greatly associated with poor survival and might be an adverse survival factor.
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Effect of fibrin sealant aided with Dexon mesh for renal repair in a rat model of partial nephrectomy.
Int J Surg
PUBLISHED: 01-29-2014
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To evaluate the clinical efficacy and histochemical impact of a new technique of renal repair using a fibrin sealant and Dexon mesh in rats.
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Galectin-1 induces vascular permeability through the neuropilin-1/vascular endothelial growth factor receptor-1 complex.
Angiogenesis
PUBLISHED: 01-19-2014
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Galectin-1 (Gal-1) is a ?-galactoside-binding lectin that regulates endothelial cell migration, proliferation, and adhesion. However, the effect of Gal-1 on vascular permeability and the underlying mechanisms are unclear. We found that high Gal-1 expression was associated with elevated tumor vascular permeability in specimens of oral squamous cell carcinoma. Using transendothelial passage of FITC-dextran and a Miles assay, we demonstrated that Gal-1 increased vascular permeability extracellularly through its carbohydrate recognition domain. Mechanism dissection revealed that the neuropilin (NRP)-1/vascular endothelial growth factor receptor- (VEGFR)-1 complex was required for Gal-1-regulated vascular permeability. Activation of VEGFR-1 triggered activation of Akt which led to a reduction in vascular endothelial-cadherin at cell-cell junctions and resulted in cytoskeletal rearrangement. Both inhibition of Gal-1 secreted from cancer cells and administration of an anti-Gal-1 antibody in the tumor microenvironment suppressed tumor growth and vascular permeability in xenograft models. In conclusion, our results demonstrate a novel function of Gal-1 of increasing vascular permeability through the NRP-1/VEGFR1 and Akt signaling pathway and indicate that targeting Gal-1 by an anti-Gal-1 antibody is a feasible therapy for vascular hyperpermeability and cancer.
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Hypersensitivity to mosquito bites as the primary clinical manifestation of an Epstein-Barr virus infection.
J Microbiol Immunol Infect
PUBLISHED: 01-15-2014
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Hypersensitivity to mosquito bites (HMB) is a rare disease characterized by intense local skin reactions with general symptoms, such as high fever and regional lymphadenopathy after mosquito bites. Epstein-Barr virus (EBV) chronic infection and NK cell lymphoproliferative disease have been reported first in diagnosed HMB patients. Here, we present the case of a 6-year-old girl with 2 months' history of bullae and necrotic skin lesions, accompanied by a high temperature, visual hallucinations, and liver dysfunction after mosquito bites. A histopathologic examination of the skin lesion showed vasculitis and EBV infection. We could not detect any findings of hematologic malignancies or NK cell proliferative disease in the patient. Clinicians should closely evaluate HMB patients for possible development of lymphoproliferative status or hematologic malignant disorders.
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Joint experimental and computational 17O solid state NMR study of Brownmillerite Ba2In2O5.
Phys Chem Chem Phys
PUBLISHED: 01-03-2014
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Structural characterization of Brownmillerite Ba2In2O5 was achieved by an approach combining experimental solid-state NMR spectroscopy, density functional theory (DFT) energetics, and GIPAW NMR calculations. While in the previous study of Ba2In2O5 by Adler et al. (S. B. Adler, J. A. Reimer, J. Baltisberger and U. Werner, J. Am. Chem. Soc., 1994, 116, 675-681), three oxygen resonances were observed in the (17)O NMR spectra and assigned to the three crystallographically unique O sites, the present high resolution (17)O NMR measurements under magic angle spinning (MAS) find only two resonances. The resonances have been assigned using first principles (17)O GIPAW NMR calculations to the combination of the O ions connecting the InO4 tetrahedra and the O ions in equatorial sites in octahedral InO6 coordination, and to the axial O ions linking the four- and six-fold coordinated In(3+) ions. Possible structural disorder was investigated in two ways: firstly, by inclusion of the high-energy structure also previously studied by Mohn et al. (C. E. Mohn, N. L. Allan, C. L. Freeman, P. Ravindran and S. Stølen, J. Solid State Chem., 2005, 178, 346-355), where the structural O vacancies are stacked rather than staggered as in Brownmillerite and, secondly, by exploring structures derived from the ground-state structure but with randomly perturbed atomic positions. There is no noticeable NMR evidence for any substantial occupancy of the high-energy structure at room temperature.
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Caveolin-1 provides palliation for adverse hepatic reactions in hypercholesterolemic rabbits.
PLoS ONE
PUBLISHED: 01-01-2014
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Caveolins are an essential component of cholesterol-rich invaginations of the plasma membrane known as caveolae. These flask-shaped, invaginated structures participate in a number of important cellular processes, including vesicular transport, cholesterol homeostasis, and signal transduction. We investigated the effects of CAV-1 on mitochondrial biogenesis and antioxidant enzymes in hypercholesterolemia-affected target organs. A total of eighteen male New Zealand white rabbits were divided into three groups: a normal-diet group, an untreated hypercholesterolemia-induced group, and a hypercholesterolemia-induced group that received intravenous administration of antennapedia-CAV-1 (AP-CAV-1) peptide every 2 days for 2 weeks. Serum biochemistry, CAV-1 distribution, neutral lipid distribution, mitochondrial morphology, biogenesis-mediated protein content, oxidative stress balance, antioxidant enzyme levels, and apoptotic cell death of liver tissue were analysed. Hepatic and circulating cholesterol and low-density lipoprotein cholesterol (LDL-C) levels differed significantly between the three groups (P<0.05). Immunohistochemical staining intensity of CAV-1 was greater in AP-CAV-1-treated rabbits than in untreated rabbits, especially in the vicinity of the liver vasculature. The high levels of neutral lipids, malondialdehyde, peroxisome proliferator-activated receptor-? coactive 1? (PGC-1?), and nuclear respiratory factor-1 (NRF-1) seen in untreated hypercholesteremic animals were attenuated by administration of AP-CAV-1 (P<0.05). In addition, mitochondria in animals that received treatment exhibited darker electron-dense matrix and integrated cristae. Furthermore, the levels of ROS modulator 1 (Romo1) and superoxide dismutase (SOD)-2, as well as catalase activity were significantly lower in CAV-1-treated hypercholesterolemic rabbits (P<0.05). AP-CAV-1 treatment also restored mitochondrial respiratory chain subunit protein content (OXPHOS complexes I-V), thereby preserving mitochondrial function (P<0.05). Furthermore, AP-CAV-1 treatment significantly suppressed apoptotic cell death, as evidenced by a reduction in the number of TUNEL-positive cells. Our results indirectly indicate that CAV-1 mediates the negative effects of PGC-1? on hepatic mitochondrial respiratory chain function, promotes the antioxidant enzyme defence system, and maintains mitochondrial biogenesis.
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Overexpression of endothelin 1 triggers hepatocarcinogenesis in zebrafish and promotes cell proliferation and migration through the AKT pathway.
PLoS ONE
PUBLISHED: 01-01-2014
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Hepatocarcinogenesis commonly involves the gradual progression from hepatitis to fibrosis and cirrhosis, and ultimately to hepatocellular carcinoma (HCC). Endothelin 1 (Edn1) has been identified as a gene that is significantly up-regulated in HBx-induced HCC in mice. In this study, we further investigated the role of edn1 in hepatocarcinogenesis using a transgenic zebrafish model and a cell culture system. Liver-specific edn1 expression caused steatosis, fibrosis, glycogen accumulation, bile duct dilation, hyperplasia, and HCC in zebrafish. Overexpression of EDN1 in 293T cells enhanced cell proliferation and cell migration in in vitro and xenotransplantation assays and was accompanied with up-regulation of several cell cycle/proliferation- and migration-specific genes. Furthermore, expression of the unfolded protein response (UPR) pathway-related mediators, such as spliced XBP1, ATF6, IRE1, and PERK, was also up-regulated at both the RNA and protein levels. In the presence of an EDN1 inhibitor or an AKT inhibitor, these increases were diminished and the EDN1-induced migration ability also was disappeared, suggesting that the EDN1 effects act through activation of the AKT pathway to enhance the UPR and subsequently activate the expression of downstream genes. Additionally, p-AKT is enhanced in the edn1 transgenic fish compared to the GFP-mCherry control. The micro RNA miR-1 was found to inhibit the expression of EDN1. We also observed an inverse correlation between EDN1 and miR-1 expression in HCC patients. In conclusion, our data suggest that EDN1 plays an important role in HCC progression by activating the PI3K/AKT pathway and is regulated by miR-1.
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Apicidin-Resistant HA22T Hepatocellular Carcinoma Cells strongly activated the Wnt/?-Catenin Signaling Pathway and MMP-2 Expression via the IGF-IR/PI3K/Akt Signaling Pathway Enhancing Cell Metastatic Effect.
Biosci. Biotechnol. Biochem.
PUBLISHED: 12-07-2013
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The IGF-IR/PI3K/Akt signaling pathway inhibited GSK3-? activity by phosphorylation and this promoted ?-catenin nuclear localization. Our previous study indicated that ?-catenin mRNA level was significantly higher in tumor areas than in non-tumor ones, especially in late pathologic stage tumors. However, ?-catenin inhibition resulted in significantly suppressed migration and invasion ability of HA22T cells. Thus, Wnt/?-catenin pathway over-activation might be involved in metastatic enhancement of apicidin-resistant HA22T cell metastasis. Apicidin-resistant (AR) HA22T cells showed higher ?-catenin nuclear accumulation and significantly decreased GSK-3-? protein level, in relation to parental cells. Results also indicated that AR cells increased abundantly in Tbx3, a downstream target of Wnt/?-catenin that it is implicated in liver cancer. AR cells also inhibited the MEK/ERK/PEA3 pathway which promoted MMP-2 activation. But, apicidin-resistant effect was totally reversed by LY294002 and AG1024. In conclusion, Apicidin-R HA22T cells activated the Wnt/?-catenin pathway and induced, MMP-2 expression via IGF-IR/PI3K/Akt signaling further enhancing cell the metastatic effects.
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Predictors of long-term survival in hepatocellular carcinomas: A longitudinal follow-up of 108 patients with small tumors.
Anticancer Res.
PUBLISHED: 11-14-2013
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Locoregional treatment [including percutaneous ethanol injection (PEI) therapy and transcatheter arterial chemoembolization (TACE)] provides an alternative treatment for early-diagnosed hepatocellular carcinoma (HCC). However, the long-term survival of patients after locoregional treatments remains unclear.
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Solvent-type-dependent polymorphism and charge transport in a long fused-ring organic semiconductor.
Nanoscale
PUBLISHED: 11-11-2013
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Crystalline polymorphism of organic semiconductors is among the critical factors in determining the structure and properties of the resultant organic electronic devices. Herein we report for the first time a solvent-type-dependent polymorphism of a long fused-ring organic semiconductor and its crucial effects on charge transport. A new polymorph of 5,11-bis(triethylsilylethynyl)anthradithiophene (TES ADT) is obtained using solvent-assisted crystallization, and the crystalline polymorphism of TES ADT thin films is correlated with their measured hole mobilities. The best-performing organic thin film transistors of the two TES ADT polymorphs show subthreshold slopes close to 1 V dec(-1), and threshold voltages close to zero, indicating that the density of traps at the semiconductor-dielectric interface is negligible in these devices and the observed up to 10-fold differences in hole mobilities of devices fabricated with different solvents are largely resultant from the presence of two TES ADT polymorphs. Moreover, our results suggest that the best-performing TES ADT devices reported in the literature correspond to the new polymorph identified in this study, which involves crystallization from a weakly polar solvent (such as toluene and chloroform).
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A Multilevel Model of Organizational Health Culture and the Effectiveness of Health Promotion.
Am J Health Promot
PUBLISHED: 11-07-2013
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Abstract Purpose . Organizational health culture is a health-oriented core characteristic of the organization that is shared by all members. It is effective in regulating health-related behavior for employees and could therefore influence the effectiveness of health promotion efforts among organizations and employees. This study applied a multilevel analysis to verify the effects of organizational health culture on the organizational and individual effectiveness of health promotion. Design . At the organizational level, we investigated the effect of organizational health culture on the organizational effectiveness of health promotion. At the individual level, we adopted a cross-level analysis to determine if organizational health culture affects employee effectiveness through the mediating effect of employee health behavior. Setting . The study setting consisted of the workplaces of various enterprises. Subjects . We selected 54 enterprises in Taiwan and surveyed 20 full-time employees from each organization, for a total sample of 1011 employees. Measures . We developed the Organizational Health Culture Scale to measure employee perceptions and aggregated the individual data to formulate organization-level data. Organizational effectiveness of health promotion included four dimensions: planning effectiveness, production, outcome, and quality, which were measured by scale or objective indicators. The Health Promotion Lifestyle Scale was adopted for the measurement of health behavior. Employee effectiveness was measured subjectively in three dimensions: self-evaluated performance, altruism, and happiness. Analysis . Following the calculation of descriptive statistics, hierarchical linear modeling (HLM) was used to test the multilevel hypotheses. Results . Organizational health culture had a significant effect on the planning effectiveness (? = .356, p < .05) and production (? = .359, p < .05) of health promotion. In addition, results of cross-level moderating effect analysis by HLM demonstrated that the effects of organizational health culture on three dimensions of employee effectiveness were completely mediated by health behavior. Conclusion . The construct connections established in this multilevel model will help in the construction of health promotion theories. The findings remind business executives that organizational health culture and employee health behavior help improve employee effectiveness.
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Face-on stacking and enhanced out-of-plane hole mobility in graphene-templated copper phthalocyanine.
Chem. Commun. (Camb.)
PUBLISHED: 11-01-2013
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Efficient out-of-plane charge transport is required in vertical device architectures, such as organic solar cells and organic light emitting diodes. Here, we show that graphene, transferred onto different technologically-relevant substrates, can be used to induce face-on molecular stacking and improve out-of-plane hole transport in copper phthalocyanine thin films.
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Genistein suppresses the isoproterenol-treated H9c2 cardiomyoblast cell apoptosis associated with P-38, Erk1/2, JNK, and NF?B signaling protein activation.
Am. J. Chin. Med.
PUBLISHED: 10-15-2013
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Heart disease (HD) is associated with estrogen and therefore gender and menopausal status. In addition, clinical evidence shows that increased serum norepinephrine is found in patients with HD. Therefore, this study aimed to investigate the cardio-protective effect of genistein, a selective estrogen receptor modulator (SERM) from soy bean extract, in H9c2 cardiomyoblast cells treated with isoproterenol (ISO), a norepinephrine analog. In this in vitro model, image data and results from western blotting shown that ISO treatment was capable of inducing cellular apoptosis, especially the mitochondrial dependent pathway. Treatment of genistein could suppress the expression of mitochondrial pro-apoptotic proteins including Bad, caspase-8, caspase-9, and caspase-3 in H9c2 treated with ISO. By contrast, several survival proteins were expressed in H9c2 treated with genistein, such as phosphor (p)-Akt, p-Bad, and p-Erk1/2. Furthermore, we confirmed that the protective role of genistein was partially mediated through the expression of Erk1/2, Akt, and NF ? B proteins by adding several pathway inhibitors. These in vitro data suggest that genistein may be a safe and natural SERM alternative to hormone therapy in cardio-protection.
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Single-incision laparoscopic colectomy using self-made glove port for benign colon diseases.
J Laparoendosc Adv Surg Tech A
PUBLISHED: 10-11-2013
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The instrument crowding derived from commercially available access devices in single-incision laparoscopic surgery (SILS) is a challenge to overcome. This study was designed to evaluate the short-term surgical outcomes of SILS by applying a self-made device in patients with benign colon diseases.
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Airflow obstruction and left ventricular filling pressure in suspected chronic obstructive pulmonary disease.
Respir Physiol Neurobiol
PUBLISHED: 09-23-2013
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Left ventricular (LV) filling impairment is present in patients with chronic obstructive pulmonary disease (COPD). Airflow obstruction is related to reduced LV end-diastolic volume, stroke volume, and cardiac output. The ratio of peak early diastolic filling velocity of the mitral inflow to peak early diastolic velocity of the mitral annulus (E/e), an echocardiographic parameter, can be applied as a surrogate marker of LV filling pressures. Forty-seven individuals with suspected COPD underwent pulmonary function tests and echocardiography. The ratio of forced expiratory volume in 1s to forced vital capacity (FEV1/FVC) and the E/e ratio were determined. Multivariate linear regression analysis showed that the FEV1/FVC ratio (?=0.01; 95% confidence interval, 0.001-0.019; p=0.036) independently predicted the log transformed E/e ratio. An increase of FEV1/FVC ratio (in percentage) by 1 unit was associated with an increase of the E/e ratio multiplied by 1.01. Airflow obstruction inversely predicts LV filling pressure in suspected COPD cases.
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Lysophosphatidic acid induces reactive oxygen species generation by activating protein kinase C in PC-3 human prostate cancer cells.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-19-2013
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Prostate cancer is one of the most frequently diagnosed cancers in males, and PC-3 is a cell model popularly used for investigating the behavior of late stage prostate cancer. Lysophosphatidic acid (LPA) is a lysophospholipid that mediates multiple behaviors in cancer cells, such as proliferation, migration and adhesion. We have previously demonstrated that LPA enhances vascular endothelial growth factor (VEGF)-C expression in PC-3 cells by activating the generation of reactive oxygen species (ROS), which is known to be an important mediator in cancer progression. Using flow cytometry, we showed that LPA triggers ROS generation within 10min and that the generated ROS can be suppressed by pretreatment with the NADPH oxidase (Nox) inhibitor diphenylene iodonium. In addition, transfection with LPA1 and LPA3 siRNA efficiently blocked LPA-induced ROS production, suggesting that both receptors are involved in this pathway. Using specific inhibitors and siRNA, phospholipase C (PLC) and protein kinase C (PKC) were also suggested to participate in LPA-induced ROS generation. Overall, we demonstrated that LPA induces ROS generation in PC-3 prostate cancer cells and this is mediated through the PLC/PKC/Nox pathway.
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Suppression of plasminogen activators and the MMP-2/-9 pathway by a Zanthoxylum avicennae extract to inhibit the HA22T human hepatocellular carcinoma cell migration and invasion effects in vitro and in vivo via phosphatase 2A activation.
Biosci. Biotechnol. Biochem.
PUBLISHED: 09-07-2013
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This study shows that the ECM degradation-associated pathway, including uPA and tPA and the downstream MMP-2/-9 protein, was significantly suppressed in HA22T cells treated with a Zanthoxylum avicennae extract (YBBE). The endogenous inhibitors, including TIMP-1/-2 and PAI-1, were enhanced in HA22T cells by the YBBE treatment. The expression of MMP-2/-9 and TIMP-1/-2 was respectively assessed by using RT-PCR and a zymography assay. The mRNA levels and enzymatic activity of MMP-2/-9 were down-regulated by the YBBE treatment in a dose-dependent manner, while the TIMP-1/-2 levels were conversely markedly increased. The PP2A siRNA or PP2A inhibitor totally reversed the YBBE effects, confirming the essential role of PP2A in YBBE inhibiting the HA22T cell migration and invasion effects. Xenografted animal experiments on nude mice demonstrated similiar results to the in vitro system. Both the in vitro and in vivo models clearly demonstrate that YBBE inhibited the highly metastatic HA22T liver cancer cell migration and invasion effects through PP2A activation.
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Activation of estrogen receptors with E2 downregulates peroxisome proliferator-activated receptor ? in hepatocellular carcinoma.
Oncol. Rep.
PUBLISHED: 08-01-2013
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Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality and occurs more often in men than in women; however, little is known about its underlying molecular mechanisms. The present study investigated the effect of estrogen receptor (ER)? and ER? on peroxisome proliferator-activated receptor ? (PPAR?) expression in Hep3B cells. We examined PPAR?, ER? and ER? mRNA and protein expression by RT-PCR and western blotting. In order to determine whether PPAR? plays a central role in HCC, we screened for PPAR? expression in liver cancer patient tissues and differentially differentiated HCC cell lines (HA22T, Huh-7, Hep3B and HepG2). We found that PPAR? expression was highly expressed in liver cancer tissues and in Hep3B cells. Furthermore, overexpression of ER? and ER? was found to decrease PPAR? expression at the transcriptional as well as at the translational level in a ligand-dependent manner. In summary, the present study demonstrated that both ER? and ? were sufficient to inhibit PPAR? and provide a valuable therapeutic option for the treatment of HCC patients.
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Anti-apoptotic and pro-survival effect of protocatechuic acid on hypertensive hearts.
Chem. Biol. Interact.
PUBLISHED: 07-27-2013
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Cardiac apoptosis was found in hearts from hypertensive animals, therefore in this study we aimed to evaluate the anti-apoptotic and pro-survival effects of protocatechuic acid (PCA) on hypertensive hearts. At first we found that, sedentary group (SHR)-PCA groups decreased TUNEL-positive apoptotic cells than SHR group alone. Protein levels of Fas ligand, Fas death receptor, Fas-associated death domain (FADD), Bid, t-Bid, Bax, cytochrome c, activated caspase-8, activated caspase 9 and activated caspase-3 were decreased in SHR-PCA group compared with SHR group. Moreover, SHR-PCA groups increased pro-survival pathway proteins like IGF1, pIGF1R, pPI3K, p-Akt, Bcl-xL, and Bcl-2 than SHR and sedentary normotensive group (WKY). All these finding suggest us that, Protocatechuic acid prevented hypertension-enhanced cardiac Fas-dependent and mitochondria-dependent apoptotic pathways and enhanced cardiac pro-survival pathway in rat models.
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Extrinsic sphingosine 1-phosphate activates S1P5 and induces autophagy through generating endoplasmic reticulum stress in human prostate cancer PC-3 cells.
Cell. Signal.
PUBLISHED: 07-24-2013
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Sphingosine 1-phosphate (S1P) is a bioactive lysophospholipid that binds to a family of G protein-coupled receptors (GPCRs), termed S1P1-S1P5. Our previous study has reported that S1P induces autophagy in human prostate cancer PC-3 cell. In addition, S1P-induced autophagy plays a prosurvival role in PC-3 cells. Accumulating evidence has shown that the autophagy responses triggered by ER stress signaling have cytoprotective effects. Thus, we attempted to investigate whether S1P-induced autophagy is a result of triggering ER stress in PC-3 cells. By monitoring XBP-1 mRNA splicing, a characteristic of ER stress, we demonstrate that S1P triggers ER stress in a concentration-dependent and time-dependent manner. Moreover, DiH S1P, a membrane-nonpermeable S1P analog without intracellular effects also enhances ER stress. Meanwhile, we also show that S1P5 is required for S1P-induced ER stress by using RNA interference experiments. Furthermore, signaling analyses revealed that PI3K, PLC, and ROS production were involved in S1Ps effects on ER stress induction. On the other hand, knockdown of XBP-1 abolished S1P-induced autophagy. In summary, our results demonstrate for the first time that the extracellular S1P-triggered ER stress is responsible for autophagy induction in PC-3 cells.
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Development of the Chinese version of the Hooper Visual Organization Test: normative data.
Int J Rehabil Res
PUBLISHED: 07-17-2013
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The present study consisted of two phases: development and psychometric validation of a Chinese version of the Hooper Visual Organization Test (HVOT) using Rasch analysis and the provision of normative data on the basis of a representative sample of the Chinese-speaking population. The HVOT was administered to 1008 healthy adults aged 15-79 years, 60 patients with stroke, and 60 patients with schizophrenia. The results indicated that with 12 items removed, the resulting 18-item scale was found to be unidimensional, with satisfactory internal consistency and no evidence of differential item functioning or bias for age, sex and educational level. There were significant differences between each of the two patient groups and normal controls on the scores of the Rasch-developed measure. All test-retest coefficients exceeded 90 in patient samples. As performance on the Chinese version decreases with age and lower years of education, regression-based normative data that took age and education into account were established. A cut-off score of 21.5, out of an x-y range, the higher the better, resulted in a sensitivity of 0.86 and a specificity of 0.68. The normative data presented here will enable clinicians to determine different levels of visuosynthetic impairments more precisely.
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Probiotic-fermented purple sweet potato yogurt activates compensatory IGF?IR/PI3K/Akt survival pathways and attenuates cardiac apoptosis in the hearts of spontaneously hypertensive rats.
Int. J. Mol. Med.
PUBLISHED: 07-09-2013
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Apoptosis is recognized as a predictor of adverse outcomes in subjects with cardiac diseases. The aim of this study was to explore the effects of probiotic-fermented purple sweet potato yogurt (PSPY) with high ?-aminobutyric acid (GABA) content on cardiac apoptosis in spontaneously hypertensive rat (SHR) hearts. The rats were orally adminsitered with 2 different concentrations of PSPY (10 and 100%) or captopril, 15.6 mg/kg, body weight (BW)/day. The control group was administered distilled water. DAPI and TUNEL staining were used to detect the numbers of apoptotic cells. A decrease in the number of TUNEL-positive cardiac myocytes was observed in the SHR-PSPY (10 and 100%) groups. In addition, the levels of key components of the Fas receptor- and mitochondrial-dependent apoptotic pathways were determined by western blot analysis. The results revealed that the levels of the key components of the Fas receptor- and mitochondrial-dependent apoptotic pathway were significantly decreased in the SHR-captopril, and 10 and 100% PSPY groups. Additionally, the levels of phosphorylated insulin-like growth factor?I receptor (p-IGF?IR) were increased in SHR hearts from the SHR-control group; however, no recovery in the levels of downstream signaling components was observed. In addition, the levels of components of the compensatory IGF-IR-dependent survival pathway (p-PI3K and p-Akt) were all highly enhanced in the left ventricles in the hearts form the SHR-10 and 100% PSPY groups. Therefore, the oral administration of PSPY may attenuate cardiomyocyte apoptosis in SHR hearts by activating IGF?IR-dependent survival signaling pathways.
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Application of quantitative estimates of fecal hemoglobin concentration for risk prediction of colorectal neoplasia.
World J. Gastroenterol.
PUBLISHED: 06-30-2013
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To determine the role of the fecal immunochemical test (FIT), used to evaluate fecal hemoglobin concentration, in the prediction of histological grade and risk of colorectal tumors.
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Aromatic hydrocarbon receptor inhibits lysophosphatidic acid-induced vascular endothelial growth factor-A expression in PC-3 prostate cancer cells.
Biochem. Biophys. Res. Commun.
PUBLISHED: 06-20-2013
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Lysophosphatidic acid (LPA) is a lipid growth factor with multiple biological functions and has been shown to stimulate cancer cell secretion of vascular endothelial growth factor-A (VEGF-A) and trigger angiogenesis. Hypoxia-inducible factor-1 (HIF-1), a heterodimer consisting of HIF-1? and HIF-1? (also known as aromatic hydrocarbon receptor nuclear translocator (ARNT)) subunits, is an important regulator of angiogenesis in prostate cancer (PC) through the enhancement of VEGF-A expression. In this study, we first confirmed the ability of LPA to induce VEGF-A expression in PC-3 cells and then validated that LPA-induced VEGF-A expression was regulated by HIF-1? and ARNT through phosphatidylinositol 3-kinase activation. Aromatic hydrocarbon receptor (AHR), a receptor for dioxin-like compounds, functions as a transcription factor through dimerization with ARNT and was found to inhibit prostate carcinogenesis and vanadate-induced VEGF-A production. Since ARNT is a common dimerization partner of AHR and HIF-1?, we hypothesized that AHR might suppress LPA-induced VEGF-A expression in PC-3 cells by competing with HIF-1? for ARNT. Here we demonstrated that overexpression and ligand activation of AHR inhibited HIF-1-mediated VEGF-A induction by LPA treatment of PC-3 cells. In conclusion, our results suggested that AHR activation may inhibit LPA-induced VEGF-A expression in PC-3 cells by attenuating HIF-1? signaling, and subsequently, suppressing angiogenesis and metastasis of PC. These results suggested that AHR presents a potential therapeutic target for the prevention of PC metastasis.
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A highly divergent Encephalomyocarditis virus isolated from nonhuman primates in Singapore.
Virol. J.
PUBLISHED: 06-10-2013
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In 2001 and 2002, fatal myocarditis resulted in the sudden deaths of four, two adult and two juvenile, orang utans out of a cohort of 26 in the Singapore Zoological Gardens.
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Thymoquinone induces apoptosis in oral cancer cells through p38? inhibition.
Am. J. Chin. Med.
PUBLISHED: 05-29-2013
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Oral cancer is a common malignancy associated with high morbidity and mortality. While p38 MAPK is reported to be involved in different cellular activities such as proliferation and differentiation, reports rarely define the roles of the individual members of the p38 MAPK family in cancer. We used two unique cell lines developed by our lab representing chemically induced oral cancer cells (T28) and non-tumor cells (N28) obtained from tissues surrounding the induced cancer as a model to screen out whether p38 MAPK is involved in the malignant transformation processes. The results suggest an association between p38? not p38? and oral cancer development. Additionally, the anti-cancer activity of thymoquinone (TQ) was screened out and we found evidences suggesting that the anti-tumor activity of TQ may be attributed to the downregulation of p38? MAPK.
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Double perovskites as a family of highly active catalysts for oxygen evolution in alkaline solution.
Nat Commun
PUBLISHED: 05-28-2013
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The electronic structure of transition metal oxides governs the catalysis of many central reactions for energy storage applications such as oxygen electrocatalysis. Here we exploit the versatility of the perovskite structure to search for oxide catalysts that are both active and stable. We report double perovskites (Ln?.?Ba?.?)CoO(?-?) (Ln=Pr, Sm, Gd and Ho) as a family of highly active catalysts for the oxygen evolution reaction upon water oxidation in alkaline solution. These double perovskites are stable unlike pseudocubic perovskites with comparable activities such as Ba?.?Sr?.?Co?.?Fe?.?O(?-?) which readily amorphize during the oxygen evolution reaction. The high activity and stability of these double perovskites can be explained by having the O p-band centre neither too close nor too far from the Fermi level, which is computed from ab initio studies.
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Large-scale modular biofiltration system for effective odor removal in a composting facility.
J Environ Sci Health A Tox Hazard Subst Environ Eng
PUBLISHED: 05-28-2013
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Several different foul odors such as nitrogen-containing groups, sulfur-containing groups, and short-chain fatty-acids commonly emitted from composting facilities. In this study, an experimental laboratory-scale bioreactor was scaled up to build a large-scale modular biofiltration system that can process 34 m(3)min(-1)waste gases. This modular reactor system was proven effective in eliminating odors, with a 97% removal efficiency for 96 ppm ammonia, a 98% removal efficiency for 220 ppm amines, and a 100% removal efficiency of other odorous substances. The results of operational parameters indicate that this modular biofiltration system offers long-term operational stability. Specifically, a low pressure drop (<45 mmH2O m(-1)) was observed, indicating that the packing carrier in bioreactor units does not require frequent replacement. Thus, this modular biofiltration system can be used in field applications to eliminate various odors with compact working volume.
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Apicidin-resistant HA22T hepatocellular carcinoma cells massively promote pro-survival capability via IGF-IR/PI3K/Akt signaling pathway activation.
Tumour Biol.
PUBLISHED: 05-22-2013
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Despite rapid advances in the diagnostic and surgical procedures, hepatocellular carcinoma (HCC) remains one of the most difficult human malignancies to treat. This may be due to the chemoresistant behaviors of HCC. It is believed that acquired resistance could be overcome and improve the overall survival of HCC patients by understanding the mechanisms of chemoresistance in HCC. A stable HA22T cancer line, which is chronically resistant to a histone deacetylase inhibitor, was established. After comparing the molecular mechanism of apicidin-R HA22T cells to parental ones by Western blotting, cell cycle-regulated proteins did not change in apicidin-R cells, but apicidin-R cells were more proliferative and had higher tumor growth (wound-healing assay and nude mice xenograft model). Moreover, apicidin-R cells displayed increased levels of p-IGF-IR, p-PI3K, p-Akt, Bcl-xL, and Bcl-2 but also significantly inhibited the tumor suppressor PTEN protein and apoptotic pathways when compared to the parental strain. Therefore, the highly proliferative effect of apicidin-R HA22T cells was blocked by Akt knockdown. For all these findings, we believe that novel strategies to attenuate IGF-IR/PI3K/Akt signaling could overcome chemoresistance toward the improvement of overall survival of HCC patients.
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Suppression of TLR-4-Related Inflammatory Pathway and Anti-Fibrosis Effects of Probiotic-Fermented Purple Sweet Potato Yogurt in Hearts of Spontaneously Hypertensive Rats.
Chin J Physiol
PUBLISHED: 05-10-2013
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Inflammation plays an important role in triggering fibrosis of cardiovascular disease and hypertension. Gamma aminobutyric acid (GABA) has hypotensive effect; GABA concentration could be enhanced in milk fermented with lactic acid bacteria (LAB). This study evaluated the effect of probiotic-fermented purple sweet potato yogurt (PSPY) on the toll-like receptor 4 (TLR-4)-related inflammatory components, and on fibrosis in the heart of spontaneously hypertensive rat (SHR). TLR4- related pathway and fibrosis-associated proteins TGF? and FGF2 were significantly increased in SHR hearts, but were highly suppressed in 10% PSPY-fed rats. Microscopic examination with Masson trichrome staining of left ventricle further demonstrated that 10% and 100% PSPY both significantly reduced interstitial fibrosis in SHR hearts. These findings indicated that oral administration of 10% probiotic-fermented PSPY was strong enough to lower cardiac fibrosis in SHR rats through the suppression of TLR-4-related inflammatory pathway. Therefore, PSPY may be included in diets to help prevent cardiac fibrosis in patients with hypertension.
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GABA Tea Prevents Cardiac Fibrosis by Attenuating TNF-alpha and Fas/FasL-mediated apoptosis in Streptozotocin-Induced Diabetic Rats.
Food Chem. Toxicol.
PUBLISHED: 05-04-2013
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GABA tea is a tea product that contains a high level of gamma-aminobutyric acid (GABA). This study investigated the effects of GABA tea on the heart in a diabetic rat model. Male Wistar rats were injected with 55 mg/kg streptozotocin (STZ) to induce diabetes for 2 weeks and then orally given dosages of 4.55 and 45.5 mg/kg/day GABA tea extract for 6 weeks. The results revealed that fasting blood glucose levels returned to normal levels in GABA tea-treated diabetic rats, but not in the untreated diabetic rats. Additionally, GABA tea effectively inhibited cardiac fibrosis induced by STZ. Further experiments showed that the STZ-induced protein levels of tumor necrosis factor-alpha (TNFalpha), Fas, activated caspase-8 and caspase-3 were significantly inhibited by the GABA tea treatment. Therefore, our data suggest that the inhibiting effect of GABA tea on STZ-induced cardiac fibrosis in diabetic rats may be mediated by reducing blood glucose and further attenuating TNF-alpha expression and/or Fas/Fas ligand (FasL)-mediated apoptosis. These findings will provide implications for the potential anti-diabetic properties of GABA tea.
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Lumbrokinase attenuates side-stream-smoke-induced apoptosis and autophagy in young hamster hippocampus: correlated with eNOS induction and NF?B/iNOS/COX-2 signaling suppression.
Chem. Res. Toxicol.
PUBLISHED: 04-05-2013
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Recent studies have found that cigarette smoke is epidemiologically linked to an increased risk for impaired cognitive development in adolescents. This study evaluated the influence of side stream smoke (SSS) exposure on hippocampal apoptosis and of the lumbrokinase (LK) effects on SSS induced apoptosis in young hamster hippocampus. Twenty male hamsters at six weeks of age were randomly divided into control group, SSS group (exposed to tobacco cigarettes smoke at doses of 10 cigarettes for 30 min twice a day for 1 month), and SSS hamsters with LK treatment (1.2 mg/kg, ip) for twice a week for 1 month. TUNEL assay and Western blotting were performed. The TUNEL-positive apoptotic cells, as well as Fas-dependent activity and mitochondria-dependent apoptotic pathways, such as Fas, FADD, activated caspase-8, t-Bid, activated caspase-9, and activated caspase-3, were significantly increased in the SSS-exposed hippocampus compared to the control and highly attenuated in the LK treatment group. Additionally, SSS exposure significantly increased the autophagy marker proteins, Beclin-1, ATG7, and LC3-II levels, in the hippocampus compared to those in the control group and obviously attenuated after LK treatment. LK also reduced hippocampus injury by enhancing eNOS expression and remarkably inhibited the proinflammatory NF?B/iNOS/COX-2 signaling activity. We found that the detrimental effects of SSS on the hippocampus are truly mediated by cell apoptosis and autophagy. However, LK reduced the hippocampus apoptosis and autophagy related injuries induced by SSS in a widespread manner. We suggest that LK presents protective effects on hippocampus apoptosis and has therapeutic potential against abnormal hippocampal function.
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Establishment of a cell-free bioassay for detecting dioxin-like compounds.
Toxicol. Mech. Methods
PUBLISHED: 03-13-2013
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Dioxins are byproducts from incomplete combustion processes and belong to a group of mostly toxic chemicals known as persistent organic pollutants, and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is considered to be the most toxic species of all dioxin-like compounds. Analytical chemical processes are employed to determine the specific dioxin content in environmental samples. However, cost-ineffectiveness and excess time consumption limit their routine utilization. The aryl hydrocarbon receptor (AhR) is the major TCDD receptor. Upon binding to dioxin, the AhR dissociates from Hsp90 and other cofactors. TCDD-bound AhR subsequently translocates to the nucleus and interacts with the AhR nuclear translocator (Arnt) to induce signal transduction. Here, we describe a highly sensitive and cost-effective alternative assay based on detecting stability of bioluminescence signals. We generated cells that stably co-express Renilla luciferase tagged-AhR (AhR-RL), Ah receptor-interacting protein (AIP), p23 and yellow fluorescent protein-tagged Arnt (Arnt-YFP) (AAPA cells) for detection of dioxin-like compounds. Treatment with 3-methylcholanthrene (3MC), AhR agonist, enhanced the interaction between AhR and Arnt and avoided proteosomal degradation. In addition, treatment with 3MC or TCDD stabilized Renilla luminescence from AhR-RL of AAPA cell-free extracts in a concentration-dependent manner. The TCDD detection limit in this cell-free system was as low as 10(-18?)M. These results highlight the potential of AAPAA cell-free extracts to detect dioxin-like pollutants.
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Endothelin-1 enhances cell migration through COX-2 up-regulation in human chondrosarcoma.
Biochim. Biophys. Acta
PUBLISHED: 03-06-2013
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Chondrosarcoma is a type of highly malignant tumor with a potent capacity of local invasion and distant metastasis. The effect of endothelin-1 (ET-1) on migration activity in human chondrosarcoma cells is not clearly understood. Here, we found that ET-1 increased the migration and expression of cyclooxygenase (COX)-2 in human chondrosarcoma cells.
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Hepatitis B virus X antigen and aflatoxin B1 synergistically cause hepatitis, steatosis and liver hyperplasia in transgenic zebrafish.
Acta Histochem.
PUBLISHED: 02-14-2013
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Aflatoxin B1 (AFB1) and the hepatitis B virus X antigen (HBx) are linked to the formation of liver diseases and hepatocellular carcinoma (HCC). The aim of this study was to investigate the synergistic effects between HBx and AFB1 in causing liver disorders using a transgenic zebrafish animal model. Histopathology, Periodic acid-Schiff (PAS) staining, Sirius red staining, TdT-mediated dUTP Nick End Labeling (TUNEL) assay, immunohistochemistry, and quantitative reverse transcriptase-polymerase chain reaction (Q-RT-PCR) were used to examine the livers of the HBx transgenic fish injected with AFB1. We found that HBx and AFB1 synergistically promoted steatosis as indicated by histopathological examinations and the increased expression of lipogenic factors, enzymes, and genes related to lipid metabolism. Moreover, treatment of AFB1 in HBx transgenic fish accelerated the development of liver hyperplasia and enhanced the expression of cell cycle related genes. PCNA was co-localized with active caspase 3 protein expression in HBx zebrafish liver samples and human HBV positive HCC samples by double fluorescence immunostaining. Finally, we found that in human patients with liver disease, significant glycogen accumulated in the inflammation, cirrhosis stage, and all cases of hepatocellular and cholangiocellular carcinoma showed a moderate cytoplasmic accumulation of glycogen. Our data demonstrated a synergistic effect of AFB1 and HBx on the regulation of lipid metabolism related genes and cell cycle/division-related genes which might contribute to enhanced steatosis and hyperplasia at 5.75months.
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A new hydrate form of diflunisal precipitated from a microemulsion system.
Colloids Surf B Biointerfaces
PUBLISHED: 02-13-2013
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Three microemulsion systems were applied as solvents for polymorph screening of seven active pharmaceutical ingredients (APIs): carbamazepine, piroxicam, sulfaguanidine, nitrofurantoin, theophylline, quercetin, and diflunisal. All the recrystallized compounds were examined by using powder X-ray diffractometry, differential scanning calorimetry, elemental analysis, Karl Fischer titration and dissolution rate. A new crystal form of diflunisal hydrate was discovered by the cooling method of recrystallization in a water-in-oil microemulsion system, composed of water, alkane and dioctyl sodium sulfosuccinate. The new hydrate form of diflunisal was characterized and confirmed to be a stoichiometry of diflunisal:water of 1:1. The other two microemulsion systems were able to convert the anhydrous diflunisal Form I to Form III. The dissolution rate of diflunisal hydrate is unexpectedly much higher than that of anhydrous ones (Forms I and III). All the other six APIs (carbamazepine, piroxicam, sulfaguanidine, nitrofurantoin, theophylline and quercetin) recrystallized from the microemulsion systems were all converted into hydrate form.
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Alpinate oxyphyllae fructus (Alpinia Oxyphylla Miq) extracts inhibit angiotensin-II induced cardiac apoptosis in H9c2 cardiomyoblast cells.
Biosci. Biotechnol. Biochem.
PUBLISHED: 02-07-2013
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Angiotensin II (Ang II) is a risk factor for cardiovascular disease. We used a traditional Chinese medicine, alpinate oxyphyllae fructus (AOF), to evaluate its effect on Ang II-induced cardiac apoptosis and mitochondrial dysfunction. Ang II-treated H9c2 cells were administered AOF of 20-100 µg/mL concentrations. Ang II significantly increased TUNEL-positive nuclei in the H9c2 cells, effect was inhibited by AOF administration in both pre-treated and post-treated H9c2 cells. Caspases 9 and 3 activities were increased by Ang II and downregulated by AOF administration, especially in pre-treatment. AOF treatment reversed Ang II-induced mitochondria membrane potential instability in H9c2 cells as observed by JC-1 stain assay. Furthermore, pro-apoptotic proteins Bad and cytochrome c increased and decreased respectively under AOF administration. The levels of p-Bad anti-apoptotic protein were significantly increased after AOF treatment. This study indicates that mitochondrial dependent apoptosis induced by Ang II.
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Using self-organization to control morphology in molecular photovoltaics.
J. Am. Chem. Soc.
PUBLISHED: 02-01-2013
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This work explores the formation of well-defined molecular p-n junctions in solution-processed self-assembled heterojunction solar cells using dodecyloxy-substituted contorted hexabenzocoronene (12-c-HBC) as a donor material and phenyl-C(70)-butyric acid methyl ester (PC(70)BM) as an acceptor. We find that the contorted 12-c-HBC molecules effectively assemble in solution to form a nested structure with the ball-shaped PC(70)BM. The result is a self-assembled molecular-scale p-n junction. When this well-defined p-n junction is embedded in active films, we can make efficient self-assembled solar cells with minimal amounts of donor material relative to the acceptor. The power conversion efficiency is drastically enhanced by the mode of donor and acceptor assembly within the film.
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1,5-Diphenylpent-3-en-1-ynes and methyl naphthalene carboxylates from Lawsonia inermis and their anti-inflammatory activity.
Phytochemistry
PUBLISHED: 01-23-2013
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Lawsonia inermis (Lythraceae) known as henna is one of the most popular and ancient plants used in cosmetics and hair dying. It is cultivated for its leaves but other parts such as seeds, flowers, stem bark and roots are also used in traditional medicine for millennia. Henna tattoo paste also proved to be beneficial for wound healing and in several skin diseases suggesting potent anti-inflammatory activity. To evaluate henna anti-inflammatory activity, 31 compounds, including three 1,5-diphenylpent-3-en-1-yne derivatives, lawsochylin A-C and three methyl naphthalene carboxylates, lawsonaphthoate A-C, were isolated from the stems and leaves of henna utilizing a bioassay-guided fractionation. The structures of the compounds were elucidated by spectroscopic data. Two compounds, lawsochylin A and lawsonaphthoate A showed potent anti-inflammatory activity by inhibition of superoxide anion generation (IC(50)=1.80 and 1.90 ?g/ml) and elastase release (IC(50)=1.58 and 3.17 ?g/ml) of human neutrophils in response to fMLP or cytochalasin B. Moreover, the known compounds, luteolin, apigenin, 4S-4-hydroxy-?-tetralone, and 2-butoxysuccinic acid, also showed potent inhibition of superoxide anion generation (IC(50)=0.75-1.78 ?g/ml) and elastase release (IC(50)=1.62-3.61 ?g/ml).
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MALDI-TOF mass spectrometry analysis of small molecular weight compounds (under 10 KDa) as biomarkers of rat hearts undergoing arecoline challenge.
Pharm Biol
PUBLISHED: 01-22-2013
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Statistical and clinical reports indicate that betel nut chewing is strongly associated with progression of oral cancer because some ingredients in betel nuts are potential cancer promoters, especially arecoline. Early diagnosis for cancer biomarkers is the best strategy for prevention of cancer progression. Several methods are suggested for investigating cancer biomarkers. Among these methods, gel-based proteomics approach is the most powerful and recommended tool for investigating biomarkers due to its high-throughput. However, this proteomics approach is not suitable for screening biomarkers with molecular weight under 10 KDa because of the characteristics of gel electrophoresis.
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The Effect of Elephantopus scaber L. on Liver Regeneration after Partial Hepatectomy.
Evid Based Complement Alternat Med
PUBLISHED: 01-10-2013
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Liver regeneration after partial hepatectomy (PHx) is a physiological response for maintaining homeostasis. The aim of this study is to investigate effects of Elephantopus scaber L.- (ESL-) induced liver regeneration on growth factors (HGF and IGF-1), cell cycle regulation, and apoptosis suppressed. In this study, we fed five Chinese medicinal herbs (1?g/kg/day), Codonopsis pilosula (CP, Dangshen), Salvia miltiorrhiza Bunge (SMB, Danshen,), Bupleurum kasi (BK, Chaihu), Elephantopus scaber L. (ESL, Teng-Khia-U), and Silymarin (Sm, 25?mg/kg) for 7 days to male Spraue-Dawley rats. Then surgical 2/3?PHx was conducted and liver regeneration mechanisms were estimated on the following 24?hrs and 72?hrs. The activities of growth factors (HGF and IGF-I) and cell cycle proteins were measured by Western blot and RT-PCR. Histological analysis and apoptosis were detected by H&E stain and TUNEL. The results showed that extraction of Elephantopus scaber L. (ESL) and Silymarin (Sm, positive control) were increased protein expression levels of HGF and IGF-1 which leads into cell cycle. These results suggest that the ESL plays a crucial role in cell cycle-induced liver regeneration and apoptosis. These results suggested that the ESL plays a crucial role in cell cycle-induced liver regeneration and suppressed hepatocytes apoptosis.
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Resection of an intra-operative ruptured hepatocellular carcinoma with continuous pringle maneuver and in situ hypothermic perfusion through the inferior mesenteric vein: a case report.
World J Surg Oncol
PUBLISHED: 01-09-2013
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Intra-operative tumor rupture is a serious complication during resection of large hepatocellular carcinoma (HCC) leading to more blood loss. We report our experience in applying continuous Pringle maneuver with in situ hypothermic perfusion via inferior mesenteric vein catheterization to the portal vein of the remnant liver for resection during an extended left lobectomy of a large HCC which ruptured intraoperatively. Using this method, we successfully managed the patient without any further morbidity. This technique provides easier accessibility of in situ perfusion, decreases operative blood loss and prevents warm ischemic injury to the remnant liver during parenchymal transection. This method could be effective for the resection of large ruptured HCC.
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Danshen mediates through estrogen receptors to activate Akt and inhibit apoptosis effect of Leu27IGF-II-induced IGF-II receptor signaling activation in cardiomyoblasts.
Food Chem. Toxicol.
PUBLISHED: 01-08-2013
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Post-menopausal women show dramatically increased cardiovascular disease morbidity (CVD). Danshen is used widely in China for the treatment of cardiovascular disorders, including coronary heart disease. Danshen possesses lipid-soluble biologically active components with a structure similar to 17?-estrodiol (E2). This study assesses whether the cardio-protection exerted by Danshen is mediated through the ERs within H9c2 cardiomyoblast cells. Cardiomyoblast cells pretreated with Fulvestrant (ICI 182,780), an estrogen receptor antagonist was applied to investigate the estrogenic activity of Danshen. The Danshen extract preventive effects on Leu27IGF-II-induced IGF-IIR signaling activator and H9c2 cell apoptosis were identified using TUNEL assay, JC-1 staining and Western blot assay. We found that Danshen extract treatments significantly enhanced phosphorylated Akt through estrogen receptor activation to inhibit Leu27IGF-II-induced calcineurin activation and block H9c2 cell apoptosis. Danshen extracts suppressed the IGF-IIR signaling proteins, pro-apoptotic proteins and reversed the mitochondrial membrane instability induced by Leu27IGF-II. However, the cardioprotective properties of Danshen to inhibit Leu27IGF-II-induced cell apoptosis and promote cell survival were attenuated by applying ICI, which suggests that the Danshen cardioprotective effect is mediated through estrogen receptors. All our data indicated that Danshen exerts strong estrogenic activity which can be considered a novel selective estrogen receptor modulator (SERM) against IGF2R signaling that blocks cardiac apoptosis.
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Clinical implications of deregulated CDK4 and Cyclin D1 expression in patients with human hepatocellular carcinoma.
Med. Oncol.
PUBLISHED: 01-05-2013
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Deregulated cell cycle can contribute to the unscheduled proliferation in cancer cells. Overexpression of cell cycle regulators CDK4 and Cyclin D1 has been reported in many cancers. The aim of this study is to determine the clinical implications of CDK4 and Cyclin D1 in hepatocellular carcinoma (HCC). The levels of mRNA and protein were analyzed by quantitative real-time RT-PCR and immunohistochemistry, respectively, in 59 paired HCC and the neighboring noncancer tissues. The relationship between CDK4 and Cyclin D1 expression, clinicopathological parameters, and prognosis was investigated. Our data demonstrated that the mRNA level of CDK4 was up-regulated (p = 0.019), while that of Cyclin D1 was down-regulated (p = 0.002), in HCC. Immunohistochemical data confirmed that CDK4 protein was increased in 73 % and Cyclin D1 protein was decreased in 66 % of HCC samples. Overexpression of CDK4 was correlated with HBV (p = 0.054, borderline significant), tumor size (p = 0.014), and stage (p = 0.010). The Kaplan-Meier survival curves showed that high CDK4 was correlated with a poor survival rate (I vs. II, p < 0.001; I vs. III, p < 0.001). Univariate analysis showed that tumor size (p = 0.002), stage (p = 0.021), and high CDK4 score (I vs. II-III, p < 0.001) were significant prognostic factors. Multivariate analysis showed that tumor size (p = 0.007) and high CDK4 score (I vs. II-III, p < 0.001) were independent factors for overall survival of HCC. The expression of Cyclin D1 was not correlated with CDK4 expression, tumor grades, survival rate, and any clinicopathological parameters. CDK4 could provide a clinical prognostic marker for HCC progression.
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Liver-specific expressions of HBx and src in the p53 mutant trigger hepatocarcinogenesis in zebrafish.
PLoS ONE
PUBLISHED: 01-01-2013
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Hepatocarcinogenesis is a multistep process that starts from fatty liver and transitions to fibrosis and, finally, into cancer. Many etiological factors, including hepatitis B virus X antigen (HBx) and p53 mutations, have been implicated in hepatocarcinogenesis. However, potential synergistic effects between these two factors and the underlying mechanisms by which they promote hepatocarcinogenesis are still unclear. In this report, we show that the synergistic action of HBx and p53 mutation triggers progressive hepatocellular carcinoma (HCC) formation via src activation in zebrafish. Liver-specific expression of HBx in wild-type zebrafish caused steatosis, fibrosis and glycogen accumulation. However, the induction of tumorigenesis by HBx was only observed in p53 mutant fish and occurred in association with the up-regulation and activation of the src tyrosine kinase pathway. Furthermore, the overexpression of src in p53 mutant zebrafish also caused hyperplasia, HCC, and sarcomatoid HCC, which were accompanied by increased levels of the signaling proteins p-erk, p-akt, myc, jnk1 and vegf. Increased expression levels of lipogenic factors and the genes involved in lipid metabolism and glycogen storage were detected during the early stages of hepatocarcinogenesis in the HBx and src transgenic zebrafish. The up-regulation of genes involved in cell cycle regulation, tumor progression and other molecular hallmarks of human liver cancer were found at later stages in both HBx and src transgenic, p53 mutant zebrafish. Together, our study demonstrates that HBx and src overexpression induced hepatocarcinogenesis in p53 mutant zebrafish. This phenomenon mimics human HCC formation and provides potential in vivo platforms for drug screening for therapies for human liver cancer.
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Anti-apoptotic and pro-survival effects of exercise training on hypertensive hearts.
J. Appl. Physiol.
PUBLISHED: 12-29-2011
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Activated cardiac apoptosis was found in hearts from hypertensive animals, but little information regarding the effects of exercise training on cardiac apoptosis in hypertension is available. The purpose of this study was to evaluate the anti-apoptotic and pro-survival effects of exercise training on hypertensive hearts.
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Phosphodiesterase 4 inhibition attenuates plasma volume loss and transvascular exchange in volume-expanded mice.
J. Physiol. (Lond.)
PUBLISHED: 11-14-2011
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We tested the hypothesis that inhibition of phosphodiesterase 4 (PDE4) with rolipram to increase vascular endothelial cAMP and stabilize the endothelial barrier would attenuate the action of endogenous atrial natriuretic peptide (ANP) to increase vascular permeability to the plasma protein albumin after an acute plasma volume expansion. After rolipram pretreatment (8 mg (kg body wt)(-1), intraperitoneal, 30 min) more than 95% of the peak increase in plasma volume after volume expansion (4.5% bovine serum albumin, 114 ?l (g body wt)(-1) h(-1), 15 min) remained in the vascular space 75 min after the end of infusion, whereas only 67% of the fluid was retained in volume-expanded animals with no rolipram pretreatment. Rolipram significantly decreased 30 min fluorescently labelled albumin clearance (?l (g dry wt)(-1)) relative to untreated volume-expanded controls in skin (e.g. back, 10.4 ± 1.6?vs. 19.5 ± 3.6,?P?= 0.04), muscle (e.g. hamstring, 15.0 ± 1.9?vs.?20.8 ± 1.4,?P?= 0.04) and in colon, caecum, and rectum (average reduction close to 50%). The mass of muscle and skin tissue accounted for 70% of volume-expansion-dependent albumin shifts from plasma to interstitium. The results are consistent with observations that the PDE4 inhibitor rolipram attenuates ANP-induced increases in vascular permeability after infusion of exogenous ANP and observations of elevated central venous pressure after a similar volume expansion in mice with selective deletion of the endothelial ANP receptor. These observations may form the basis for new strategies to retain intravenous fluid containing macromolecules.
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Ab initio and empirical defect modeling of LaMnO(3±?) for solid oxide fuel cell cathodes.
Phys Chem Chem Phys
PUBLISHED: 11-14-2011
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Sr doped LaMnO(3) is a perovskite widely used for solid oxide fuel cell (SOFC) cathodes. Therefore, there is significant interest in its defect chemistry. However, due to coupling of defect reactions and inadequate constraints of the defect reaction equilibrium constants obtained from thermogravimetry analysis, large discrepancies (up to 4 eV) exist in the literature for defect energetics for Sr doped LaMnO(3). In this work we demonstrate how ab initio energetics and empirical modelling can be combined to develop a defect model for LaMnO(3). Defect formation enthalpies, including concentration dependence due to defect interactions, are extracted from ab initio energies calculated at various defect concentrations. Defect formation entropies for the defect reactions in LaMnO(3) involving O(2-)(solid) ? ½O(2)(gas) + 2e(-) are shown to be accessible through combining the gas phase thermodynamics and simple models for the solid phase vibrational contributions. This simple treatment introduces a useful constraint on fitting defect formation entropies. The predicted defect concentrations from the model show good agreement with experimental oxygen nonstoichiometry vs. P(O(2)) for a wide range of temperatures (T = 873-1473 K), suggesting the effectiveness of the ab initio defect energetics in describing the defect chemistry of LaMnO(3). Further incorporating a temperature dependent charge disproportionation energy within 0.0-0.2 eV, the model is capable of describing both defect chemistry and oxygen tracer diffusivity of LaMnO(3). The model suggests an important role for defect interactions which are typically excluded from LaMnO(3) defect models, and sensitivity of the oxygen defect concentration to the charge disproportionation energy in the high P(O(2)) region. Similar approaches to those used here can be used to model the defect chemistry for other complex oxides.
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Annealing sequence dependent open-circuit voltage of inverted polymer solar cells attributable to interfacial chemical reaction between top electrodes and photoactive layers.
Langmuir
PUBLISHED: 08-05-2011
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The ability to laminate and delaminate top metal contacts during the processing and testing of inverted polymer solar cells has led us to uncover the peculiar dependence of their open-circuit voltage (V(oc)) on the annealing sequence. Specifically, thermally annealing inverted polymer solar cells having bulk-heterojunction photoactive layers after top electrode deposition above 100 °C leads to lower V(oc) compared to analogous devices with unannealed photoactive layers or photoactive layers that have been annealed prior to metal electrode deposition. This reduction in V(oc), however, can be reversed when the top electrodes are replaced. This observation is thus a strong indication that such changes in V(oc) with annealing sequence are manifestations of changes at the top electrode-photoactive layer interface, and not structural changes in the bulk of the photoactive layer. Electronic characterization conducted on the photoactive layers and metal contacts after dissection of the polymer solar cells via delamination suggests the reduction of V(oc) on thermal annealing in the presence of the metal top contacts to stem from an interfacial chemical reaction between the photoactive layers and the metal electrodes. This chemically generated interfacial layer is removed upon electrode delamination, effectively reverting the V(oc) to its original value prior to thermal annealing when the top electrodes are replaced.
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Automatic estimation of voice onset time for word-initial stops by applying random forest to onset detection.
J. Acoust. Soc. Am.
PUBLISHED: 07-27-2011
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The voice onset time (VOT) of a stop consonant is the interval between its burst onset and voicing onset. Among a variety of research topics on VOT, one that has been studied for years is how VOTs are efficiently measured. Manual annotation is a feasible way, but it becomes a time-consuming task when the corpus size is large. This paper proposes an automatic VOT estimation method based on an onset detection algorithm. At first, a forced alignment is applied to identify the locations of stop consonants. Then a random forest based onset detector searches each stop segment for its burst and voicing onsets to estimate a VOT. The proposed onset detection can detect the onsets in an efficient and accurate manner with only a small amount of training data. The evaluation data extracted from the TIMIT corpus were 2344 words with a word-initial stop. The experimental results showed that 83.4% of the estimations deviate less than 10 ms from their manually labeled values, and 96.5% of the estimations deviate by less than 20 ms. Some factors that influence the proposed estimation method, such as place of articulation, voicing of a stop consonant, and quality of succeeding vowel, were also investigated.
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Role of majority and minority carrier barriers silicon/organic hybrid heterojunction solar cells.
Adv. Mater. Weinheim
PUBLISHED: 07-14-2011
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A hybrid approach to solar cells is demonstrated in which a silicon p-n junction, used in conventional silicon-based photovoltaics, is replaced by a room-temperature fabricated silicon/organic heterojunction. The unique advantage of silicon/organic heterojunction is that it exploits the cost advantage of organic semiconductors and the performance advantages of silicon to enable potentially low-cost, efficient solar cells.
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Predicting adherence to health care recommendations using health promotion behaviours in kidney transplant recipients within 1-5 years post-transplant.
J Clin Nurs
PUBLISHED: 07-13-2011
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This study examined health promotion behaviours of kidney transplant recipients, 1-5 years after transplant and identified the risk factors predicting non-adherence to post-transplant recommendations.
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Nanoparticle-coated separators for lithium-ion batteries with advanced electrochemical performance.
Phys Chem Chem Phys
PUBLISHED: 07-06-2011
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We report a simple, scalable approach to improve the interfacial characteristics and, thereby, the performance of commonly used polyolefin based battery separators. The nanoparticle-coated separators are synthesized by first plasma treating the membrane in oxygen to create surface anchoring groups followed by immersion into a dispersion of positively charged SiO(2) nanoparticles. The process leads to nanoparticles electrostatically adsorbed not only onto the exterior of the surface but also inside the pores of the membrane. The thickness and depth of the coatings can be fine-tuned by controlling the ?-potential of the nanoparticles. The membranes show improved wetting to common battery electrolytes such as propylene carbonate. Cells based on the nanoparticle-coated membranes are operable even in a simple mixture of EC/PC. In contrast, an identical cell based on the pristine, untreated membrane fails to be charged even after addition of a surfactant to improve electrolyte wetting. When evaluated in a Li-ion cell using an EC/PC/DEC/VC electrolyte mixture, the nanoparticle-coated separator retains 92% of its charge capacity after 100 cycles compared to 80 and 77% for the plasma only treated and pristine membrane, respectively.
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Human papillomavirus infection in lung and esophageal cancers: analysis of 485 Asian cases.
J. Med. Virol.
PUBLISHED: 06-17-2011
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The role of human papillomavirus (HPV) in the development of lung and esophageal cancer remains inconclusive, which is in contrast to the established role HPV plays in the development of uterine cervical cancer. One of the reasons for this is the difference among reported HPV infection rates in these cancers. An analysis of 485 lung and esophageal cancers (176 lung squamous cell carcinoma, 128 lung adenocarcinoma, 181 esophageal carcinoma) in eight institutions in Asia (Tokyo, Kochi, Kagoshima, and Okinawa, Japan; Seoul and Daegu, Korea; Changhua, Republic of China (Taiwan); Singapore, Singapore) was carried out in order to clarify infection rates with HPV. Samples were examined in one laboratory of the Department of Pathology, the University of Tokyo, Japan in order to avoid inter-laboratory variation using a combination of polymerase chain reaction and in situ hybridization (ISH). HPV was found in 6.3%, 7%, and 9.4% of patients with lung squamous cell carcinoma, lung adenocarcinoma, and esophageal cancer, respectively. Among the geographic areas surveyed, Kagoshima exhibited a significantly higher prevalence of HPV infection in cases of esophageal carcinoma (24.1%). There was no geographical difference in the infection rates of HPV in lung carcinomas. Subtype-specific ISH was also performed, which identified the high-risk HPV types 16/18 in the majority (75.7%) of the patients with lung and esophageal cancer positive for HPV.
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Isomerically pure electron-deficient anthradithiophenes and their acceptor performance in polymer solar cells.
Chem. Commun. (Camb.)
PUBLISHED: 06-10-2011
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Amide functionalized anthradithiophenes (ADTs) play active acceptor roles in polymer bulk-heterojunction solar cells. The first separation of ADT isomers is reported, and the regiochemistry of the ADT has significant impact on crystal packing and solar cell performance. Cell efficiency up to 0.80%, due in large part to high open-circuit voltage (V(OC) > 1.0 V), is achieved in bulk-heterojunction solar cells comprising syn-ADT and poly(3-hexylthiophene).
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Neuroprotective effects of granulocyte-colony stimulating factor in a novel transgenic mouse model of SCA17.
J. Neurochem.
PUBLISHED: 06-02-2011
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Spinocerebellar ataxia type 17 (SCA17) is an autosomal dominant inherited disorder characterized by degeneration of spinocerebellar tracts and selected brainstem neurons owing to the expansion of a CAG repeat of the human TATA-binding protein (hTBP) gene. To gain insight into the pathogenesis of this hTBP mutation, we generated transgenic mice with the mutant hTBP gene driven by the Purkinje specific protein (Pcp2/L7) gene promoter. Mice with the expanded hTBP allele developed ataxia within 2-5 months. Behavioral analysis of L7-hTBP transgenic mice showed reduced fall latency in a rotarod assay. Purkinje cell degeneration was identified by immunostaining of calbindin and IP3R1. Reactive gliosis and neuroinflammation occurred in the transgenic cerebellum, accompanied by up-regulation of GFAP and Iba1. The L7-hTBP transgenic mice were thus confirmed to recapitulate the SCA17 phenotype and were used as a disease model to explore the potential of granulocyte-colony stimulating factor in SCA17 treatment. Our results suggest that granulocyte-colony stimulating factor has a neuroprotective effect in these transgenic mice, ameliorating their neurological and behavioral deficits. These data indicate that the expression of the mutant hTBP in Purkinje cells is sufficient to produce cell degeneration and an ataxia phenotype, and constitutes a good model for better analysis of the neurodegeneration in SCA17.
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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.