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Find video protocols related to scientific articles indexed in Pubmed.
Molecular epidemiology of Japanese encephalitis virus in mosquitoes in Taiwan during 2005-2012.
PLoS Negl Trop Dis
PUBLISHED: 10-01-2014
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Japanese encephalitis (JE) is a mosquito-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). Pigs and water birds are the main amplifying and maintenance hosts of the virus. In this study, we conducted a JEV survey in mosquitoes captured in pig farms and water bird wetland habitats in Taiwan during 2005 to 2012. A total of 102,633 mosquitoes were collected. Culex tritaeniorhynchus was the most common mosquito species found in the pig farms and wetlands. Among the 26 mosquito species collected, 11 tested positive for JEV by RT-PCR, including Cx. tritaeniorhynchus, Cx. annulus, Anopheles sinensis, Armigeres subalbatus, and Cx. fuscocephala. Among those testing positive, Cx. tritaeniorhynchus was the predominant vector species for the transmission of JEV genotypes I and III in Taiwan. The JEV infection rate was significantly higher in the mosquitoes from the pig farms than those from the wetlands. A phylogenetic analysis of the JEV envelope gene sequences isolated from the captured mosquitoes demonstrated that the predominant JEV genotype has shifted from genotype III to genotype I (GI), providing evidence for transmission cycle maintenance and multiple introductions of the GI strains in Taiwan during 2008 to 2012. This study demonstrates the intense JEV transmission activity in Taiwan, highlights the importance of JE vaccination for controlling the epidemic, and provides valuable information for the assessment of the vaccine's efficacy.
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Looking into meta-atoms of plasmonic nanowire metamaterial.
Nano Lett.
PUBLISHED: 08-26-2014
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Nanowire-based plasmonic metamaterials exhibit many intriguing properties related to the hyperbolic dispersion, negative refraction, epsilon-near-zero behavior, strong Purcell effect, and nonlinearities. We have experimentally and numerically studied the electromagnetic modes of individual nanowires (meta-atoms) forming the metamaterial. High-resolution, scattering-type near-field optical microscopy has been used to visualize the intensity and phase of the modes. Numerical and analytical modeling of the mode structure is in agreement with the experimental observations and indicates the presence of the nonlocal response associated with cylindrical surface plasmons of nanowires.
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Custom-designed arrays of anodic alumina nanochannels with individually tunable pore sizes.
Nanotechnology
PUBLISHED: 07-25-2014
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We demonstrate a process to selectively tune the pore size of an individual nanochannel in an array of high-aspect-ratio anodic aluminum oxide (AAO) nanochannels in which the pore sizes were originally uniform. This novel process enables us to fabricate arrays of AAO nanochannels of variable sizes arranged in any custom-designed geometry. The process is based on our ability to selectively close an individual nanochannel in an array by using focused ion beam (FIB) sputtering, which leads to redeposition of the sputtered material and closure of the nanochannel with a capping layer of a thickness depending on the energy of the FIB. When such a partially capped array is etched in acid, the capping layers are dissolved after different time delays due to their different thicknesses, which results in differences in the time required for the following pore-widening etching processes and therefore creates an array of nanochannels with variable pore sizes. The ability to fabricate such AAO templates with high-aspect-ratio nanochannels of tunable sizes arranged in a custom-designed geometry paves the way for the creation of nanophotonic and nanoelectronic devices.
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Spatial Measurement of Mobility Barriers: Improving the Environment of Community Dwelling Older Adults in Taiwan.
J Aging Phys Act
PUBLISHED: 06-12-2014
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Mobility barriers can impede physical activity, increase the fear of falling, and pose a threat to the ability of older adults to live independently. This study investigated outdoor mobility barriers within a nonretirement public housing community, located in Tainan, Taiwan. Site observations and interviews with older adult residents determined that parked motor scooters, potted plants, the rubber tiles of play areas, and a set of steps were the most important barriers. In addition, the space syntax parameters of control value and mean depth were effectively able to quantitatively measure improvements in walkability resulting from the hypothesized removal of these four barriers. These measures of improved walkability can be included in a cost-benefit analysis of spatial improvement factors to help policymakers address the mobility and accessibility needs of older adults.
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Elevated plasma stromal-cell-derived factor-1 protein levels correlate with severity in patients with community-acquired pneumonia.
Dis. Markers
PUBLISHED: 04-28-2014
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Background. The aim of this study was to investigate differential changes in plasma levels of stromal-cell-derived factor-1 (SDF-1) before and after antibiotic treatment in patients with community-acquired pneumonia (CAP) and observe the association between the severity of CAP and the plasma SDF-1 level. Methods. We gathered blood specimens from 61 adult CAP patients before and after antibiotic treatment and from 60 healthy controls to measure the plasma concentrations of SDF-1 by using an enzyme-linked immunosorbent assay. Results. The plasma SDF-1 concentration was elevated significantly in patients with CAP before receiving treatment compared with the controls and decreased significantly after the patients received treatment. Leukocyte (WBC) and neutrophil counts and C-reactive protein (CRP) levels decreased significantly after antibiotic treatment. Moreover, differences in the plasma concentration of SDF-1 were significantly correlated with PSI, CURB-65, and APACHE II scores (r = 0.389, P = 0.002, and n = 61; r = 0.449, P < 0.001, and n = 61; and r = 0.363, P = 0.004, and n = 61, resp.). Conclusions. An elevated plasma SDF-1 concentration can be used as a biological marker for the early diagnosis of CAP and for the early detection of its severity.
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Peginterferon alfa-2a with or without low-dose ribavirin for treatment-naive patients with hepatitis C virus genotype 2 receiving haemodialysis: a randomised trial.
Gut
PUBLISHED: 04-22-2014
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Data comparing the efficacy and safety of combination therapy with peginterferon plus low-dose ribavirin and peginterferon monotherapy in treatment-naive haemodialysis patients with hepatitis C virus genotype 2 (HCV-2) infection are limited.
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Association of interleukin-16 polymorphisms with graves' disease in a Taiwanese population.
Chin J Physiol
PUBLISHED: 04-04-2014
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Graves' disease (GD) is a complex, organ-specific autoimmune disease wherein the thyroid gland becomes enlarged and overactive. During GD progression, T cells secrete interleukin-16 (IL-16) to promote inflammation, act as chemoattractants that recruit more inflammatory cells, and activate target cells to enhance the development of GD. To investigate the role of IL-16 in GD, we genotyped 474 patients with GD at 8 single-nucleotide polymorphisms (SNPs) in the IL-16 gene. The IL-16 SNP rs8028364 was found to be associated with GD when compared with the control subjects (P = 2.93 × 10?¹?; CG genotype: odds ratio [OR] = 0.2 [0.07, 0.59]; CC genotype: OR = 0.03 [0.01, 0.09]). The rs1131445 polymorphism was found to be associated with GD under the allelic model (P = 0.01; G allele: OR = 1.97 [1.17, 3.32]). Sliding-window haplotype analysis by the PLINK program showed that the most significant haplotype was provided by the 6-SNP haplotype window, consisting of rs7182786, rs8028364, rs12907134, rs4128767, rs4072111 and rs8031107 (P = 2.31 × 10??¹). We found 2 protective haplotypes: GCAAGG (P = 8.69 × 10??; OR = 0.22 [0.12, 0.41]) and AGAAGG (P = 0.0012; OR = 0.26 [0.12, 0.6]). In addition, GGGGAA (P = 0.39; OR = 2.32 [1.08, 4.99]) and GGGAGA (P = 1.18 × 10??; OR = 5.54 [2.50, 12.31]) were found to be the two high-risk haplotypes. These results suggest that polymorphisms in IL-16 may be used as genetic markers for the diagnosis and prognosis of GD.
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The occurrence of primary hepatic adenoma in deceased donor renal transplant recipient.
Int Braz J Urol
PUBLISHED: 03-20-2014
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We reported a case of new-onset, multi-focal hepatic adenoma in an 18 year-old man with no classic risk factors occurring forty months after a renal transplant from a cadaver donor. Histopathology of the adenoma was examined and genotype and phenotype were also analyzed. Histopathologic examination of the adenoma showed no malignancy. Genotype and phenotype analysis revealed no HNF1? or ?-catenin gene mutations and no inflammatory infiltration. The patient was well and disease-free postoperatively. CASE HYPOTHESIS: Hepatic adenoma occurs mostly in those taking oral contraceptives or androgenic-anabolic steroids or in those with hereditary diseases. Hepatic adenoma in a renal transplant recipient is rare and has only been reported in one case with glycogen storage disease type Ia. Immunosuppressive treatment might have contributed to the development of the neoplasm.
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Dual role of acetaminophen in promoting hepatoma cell apoptosis and kidney fibroblast proliferation.
Mol Med Rep
PUBLISHED: 02-28-2014
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Acetaminophen (APAP), is a safe analgesic and antipyretic drug at therapeutic dose, and is widely used in the clinic. However, high doses of APAP can induce hepatotoxicity and nephrotoxicity. Most studies have focused on high?dose APAP?induced acute liver and kidney injury. So far, few studies have investigated the effects of the therapeutic dose (1/10 of the high dose) or of the low dose (1/100 of the high dose) of APAP on the cells. The aim of this study was to investigate the cellular effects of therapeutic- or low?dose APAP treatment on hepatoma cells and kidney fibroblasts. As expected, high?dose APAP treatment inhibited while therapeutic and low?dose treatment did not inhibit cell survival of kidney tubular epithelial cells. In addition, therapeutic-dose treatment induced an increase in the H2O2 level, activated the caspase?9/?3 cascade, and induced cell apoptosis of hepatoma cells. Notably, APAP promoted fibroblast proliferation, even at low doses. This study demonstrates that different cellular effects are exerted upon treatment with different APAP concentrations. Our results indicate that treatment with the therapeutic dose of APAP may exert an antitumor activity on hepatoma, while low?dose treatment may be harmful for patients with fibrosis, since it may cause proliferation of fibroblasts.
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Association between Helicobacter pylori Infection and Risk of Osteoporosis in Elderly Taiwanese Women with Upper Gastrointestinal Diseases: A Retrospective Patient Record Review.
Gastroenterol Res Pract
PUBLISHED: 02-21-2014
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Introduction. Helicobacter pylori (H. pylori) infection could lead to chronic local and systemic immune response. The resulting increase in proinflammatory cytokines could affect bone resorption and might increase the risk of osteoporosis. This study aimed to investigate the association between H. pylori infection and osteoporosis in elderly female patients with upper gastrointestinal diseases. Methods. A retrospective patient record review study was conducted in a regional teaching hospital in south Taiwan. Relevant information on female patients aged 65 and over who were diagnosed with diseases of esophagus, gastric ulcer, or duodenal ulcer during January 2008 to December 2010 were abstracted. Association between H. pylori infection and osteoporosis was evaluated using multivariate logistic regression analysis. Results. Of the 365 patients with a mean age of 77.3 years, 77 (21.1%) had H. pylori infection and 101 (27.7%) had been diagnosed with osteoporosis. Multivariate logistic regression analysis revealed that osteoporosis was significantly associated with H. pylori infection (adjusted odds ratio = 2.03, 95% confidence interval = 1.14-3.62) after adjusting for age group, body mass index group, and use of proton pump inhibitor. Conclusion. Osteoporosis was found to be associated with H. pylori infection in Taiwanese female patients with upper gastrointestinal diseases. Further studies with information on potential confounders are needed to confirm the association.
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Ginkgo biloba extract inhibits oxidized low-density lipoprotein (oxLDL)-induced matrix metalloproteinase activation by the modulation of the lectin-like oxLDL receptor 1-regulated signaling pathway in human umbilical vein endothelial cells.
J. Vasc. Surg.
PUBLISHED: 02-14-2014
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The overexpression of matrix metalloproteinases (MMPs) induced by oxidized low-density lipoprotein (oxLDL) has been found in atherosclerotic lesions. Previous reports have identified that oxLDL, via the upregulation of lectin-like ox-LDL receptor 1 (LOX-1), modulates the expression of MMPs in endothelial cells. Ginkgo biloba extract (GbE), from Ginkgo biloba leaves, has often been considered as a therapeutic compound for cardiovascular and neurologic diseases. However, further investigation is needed to ascertain the probable molecular mechanisms underlying the antiatherogenic effects of GbE. The aim of this study was to investigate the effects of GbE on oxLDL-activated MMPs of human endothelial cells and to test the involvement of LOX-1 and protein kinase C (PKC)-?, extracellular signal-regulated kinase (ERK), and peroxisome proliferator-activated receptor-? (PPAR-?).
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DNA topoisomerase III alpha regulates p53-mediated tumor suppression.
Clin. Cancer Res.
PUBLISHED: 02-13-2014
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Human DNA topoisomerase III alpha (hTOP3?) is involved in DNA repair surveillance and cell-cycle checkpoints possibly through formatting complex with tumor suppressors. However, its role in cancer development remained unsolved.
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RC-6 ribonuclease induces caspase activation, cellular senescence and neuron-like morphology in NT2 embryonal carcinoma cells.
Oncol. Rep.
PUBLISHED: 02-11-2014
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Frog ribonucleases have been demonstrated to have anticancer activities. However, whether RC-6 ribonuclease exerts anticancer activity on human embryonal carcinoma cells remains unclear. In the present study, RC-6 induced cytotoxicity in NT2 cells (a human embryonal carcinoma cell line) and our studies showed that RC-6 can exert anticancer effects and induce caspase-9 and -3 activities. Moreover, to date, there is no evidence that frog ribonuclease-induced cytotoxicity effects are related to cellular senescence. Therefore, our studies showed that RC-6 can increase p16 and p21 protein levels and induce cellular senescence in NT2 cells. Notably, similar to retinoic acid-differentiated NT2 cells, neuron-like morphology was found on some remaining live cells after RC-6 treatment. In conclusion, our study is the first to demonstrate that RC-6 can induce cytotoxic effects, caspase-9/-3 activities, cellular senescence and neuron-like morphology in NT2 cells.
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Robot-assisted renal transplantation in the retroperitoneum.
Transpl. Int.
PUBLISHED: 01-05-2014
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Minimally invasive surgery for renal transplantation is still under development. We employed the robotic surgical system to perform renal transplantation with a minimally invasive wound. The operation was performed with a Gibson incision and two working ports. The space for the transplantation was created by retroperitoneal dissection with the robot lifting the abdominal wall. Vascular reconstruction was performed with two robotic needle drivers. We successfully performed robot-assisted renal transplantation in five female and five male patients with an average wound length of 7.7 ± 1.04 cm. Nine of the renal allografts functioned immediately, but one with prolonged warm ischemia during the live donor nephrectomy had delayed function. The average creatinine level and estimated glomerular filtration rate at discharge were 1.31 ± 0.31 mg/dl and 58.2 ± 8.1 ml/min, respectively. All the transplants are currently functioning at 6.9 ± 3.9 months after operations. In conclusion, with robot assistance, minimal invasive renal transplantation can be performed successfully in the retroperitoneum.
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Human spotted fever group rickettsioses are underappreciated in southern Taiwan, particularly for the species closely-related to Rickettsia felis.
PLoS ONE
PUBLISHED: 01-01-2014
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Despite increased identification of spotted fever group rickettsioses (SFGR) in animals and arthropods, human SFGR are poorly characterized in Taiwan.
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Vestibular rehabilitation ameliorates chronic dizziness through the SIRT1 axis.
Front Aging Neurosci
PUBLISHED: 01-01-2014
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Dizziness is a common clinical symptom frequently referred to general neurologists and practitioners. Exercise intervention, in the form of vestibular rehabilitation, is known as an effective clinical management for dizziness. This intervention is reported to have a functional role in correcting dizziness, improving gaze stability, retraining balance and gait, and enhancing physical fitness. Dizziness is known to be highly related to inflammation and oxidative stress. SIRT1 is a major molecule for the regulation of inflammation and mitigation of oxidative stress in chronic diseases such as atherosclerosis and chronic obstructive pulmonary disease. However, the bio-molecular roles of SIRT1 involved in the pathogenesis of dizziness are still largely unclear. In this study, a total of 30 subjects were recruited (15 patients with chronic dizziness, and 15 age/gender matched non-dizzy control subjects). The dizzy subjects group received 18 sessions of 30-min vestibular training. We found that the mRNA and protein expression levels of SIRT1 in the blood samples of chronic dizzy patients were repressed compared with those of healthy controls. After vestibular training, the dizzy patients had significant symptomatic improvements. The SIRT1 expression and its downstream genes (PPAR-? and PGC-1?) were upregulated after vestibular exercises in dizzy subjects. Notably, the catalytic activity of SIRT1, NADPH and antioxidant enzyme activities were also activated in dizzy patients after vestibular training. Furthermore, vestibular exercise training reduced oxidative events and p53 expression in patients with dizziness. This study demonstrated that vestibular exercise training improved dizziness symptoms, and mechanisms for alleviation of chronic dizziness may partly involve the activation of the SIRT1 axis and the repression of redox status.
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Primary small cell carcinoma of kidney after renal transplantation: a case report and literature review.
Chin. J. Cancer Res.
PUBLISHED: 11-21-2013
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Extrapulmonary small cell carcinoma (EPSCC) is a rare neoplasm comprising 2.5% to 5% of small cell carcinomas (SCCs). Bladder SCC is the most common site of genitourinary tract. Primary renal SCC is extremely rare. We report a case of primary SCC of the kidney which is rarely reported in the urinary tract and presents an aggressive clinical picture. A 59-year-old female visited a urologic clinic with complaint of persistent left flank soreness 10 years after undergoing renal transplantation. Abdominal computed tomography showed a left renal pelvis tumor. After the patient received left nephroureterectomy with bladder cuff resection, her pathology results showed SCC. After surgery, she received adjuvant systemic chemotherapy, and her recovery has been uneventful as of 8 months. Primary renal SCC presents with an advanced tumor stage and a short median survival period, therefore early intervention and close follow-up are recommended.
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Aspirin attenuates Vinorelbine-induced endothelial inflammation via modulating SIRT1/AMPK axis.
Biochem. Pharmacol.
PUBLISHED: 10-03-2013
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Vinorelbine (VNR), a semisynthetic vinca alkaloid acquired from vinblastine, is frequently used as the candidate for intervention of solid tumors. Nevertheless, VNR-caused endothelial injuries may lead a mitigative effect of clinical treatment efficiency. A growing body of evidence reveals that aspirin is a potent antioxidant and anti-inflammation drug. We investigated whether aspirin attenuate VNR-induced endothelial dysfunction. Human endothelial cells (EA.hy926) were treated with VNR to cause endothelial inflammation. Western blotting, ROS assay, ELISA were used to confirm the anti-inflammatory effect of aspirin. We confirmed that VNR supresses SIRT1 expression, reduced LKB1 and AMPK phosphorylation as well as enriched PKC activation in treated endothelial cells. Furthermore, the membrane translocation assay displayed that the levels of NADPH oxidase subunits p47phox and Rac-1 in membrane fractions of endothelial cells were higher in cells that had been treated with VNR for than in untreated cells. We corroborated that treatment of Aspirin significantly diminishes VNR-repressed SIRT1, LKB1 and AMPK phosphorylation and VNR-promoted NADPH oxidase activation, however, those findings were vanished by SIRT1 and AMPK siRNAs. Our data also shown that Aspirin represses VNR-activated TGF-beta-activated kinase-1 (TAK1) activation, inhibited the interaction of TAK1/TAK-binding protein1 (TAB1), suppressed NF-kappa B activation and pro-inflammatory cytokine secretion. We demonstrated a novel connection between VNR-caused oxidative damages and endothelial dysfunction, and provide further insight into the protective effects of aspirin in VNR-caused endothelial dysfunction.
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Melanin bleaching with dilute hydrogen peroxide: a simple and rapid method.
Appl. Immunohistochem. Mol. Morphol.
PUBLISHED: 09-27-2013
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Melanins are naturally occurring pigments in both normal and pathologic tissues. Two common bleaching processes are potassium permanganate followed by oxalic acid treatment and dilute hydrogen peroxide (H2O2) process. The potassium permanganate/oxalic acid method is faster and more easily incorporated in conventional daily immunostaining protocols, whereas the dilute H2O2 method requires 24 hours. This study aimed to reduce melanin bleaching time by using a 10% H2O2 dilution. First, reaction time was reduced to 30 minutes by raising the temperature to 65°C. Second, containers with high thermal conductivity were used to improve bleaching effectiveness. Experimental comparisons of melanin treatments with H2O2 contained in an iron jar, a glass coplin jar, and a plastic steel jar obtained bleaching time of 20, 30, and 40 minutes, respectively. These modifications of the conventional bleaching method significantly improve the speed and efficiency of the procedure and are recommended when performing immunohistochemical studies.
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A negative feedback of the HIF-1? pathway via interferon-stimulated gene 15 and ISGylation.
Clin. Cancer Res.
PUBLISHED: 09-20-2013
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The IFN-stimulated gene 15 (ISG15)- and ubiquitin-conjugation pathways play roles in mediating hypoxic and inflammatory responses. To identify interaction(s) between these two tumor microenvironments, we investigated the effect of ISG15 on the activity of the master hypoxic transcription factor HIF-1?.
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On the structural basis and design guidelines for type II topoisomerase-targeting anticancer drugs.
Nucleic Acids Res.
PUBLISHED: 09-14-2013
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Type II topoisomerases (Top2s) alter DNA topology via the formation of an enzyme-DNA adduct termed cleavage complex, which harbors a transient double-strand break in one DNA to allow the passage of another. Agents targeting human Top2s are clinically active anticancer drugs whose trapping of Top2-mediated DNA breakage effectively induces genome fragmentation and cell death. To understand the structural basis of this drug action, we previously determined the structure of human Top2 ?-isoform forming a cleavage complex with the drug etoposide and DNA, and described the insertion of drug into DNA cleavage site and drug-induced decoupling of catalytic groups. By developing a post-crystallization drug replacement procedure that simplifies structural characterization of drug-stabilized cleavage complexes, we have extended the analysis toward other structurally distinct drugs, m-AMSA and mitoxantrone. Besides the expected drug intercalation, a switch in ribose puckering in the 3-nucleotide of the cleavage site was robustly observed in the new structures, representing a new mechanism for trapping the Top2 cleavage complex. Analysis of drug-binding modes and the conformational landscapes of the drug-binding pockets provide rationalization of the drugs structural-activity relationships and explain why Top2 mutants exhibit differential effects toward each drug. Drug design guidelines were proposed to facilitate the development of isoform-specific Top2-targeting anticancer agents.
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The complete mitochondrial genome sequence of Onychostoma alticorpus (Cypriniformes, Cyprinidae).
Mitochondrial DNA
PUBLISHED: 08-31-2013
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Abstract We determined the complete mitochondrial genome (mitogenome) sequence of Onychostoma alticorpus, which is known as an endemic freshwater species in Taiwan, by using long polymerase chain reaction method. The total length of O. alticorpus mitogenome is 16,680?bp, consisting of 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a noncoding control region. The overall base composition of O. alticorpus is 30.88% for A, 23.57% for T, 16.56% for G and 28.99% for C, with a slight AT bias of 54.45%. Gene location and specific usage of distinct termination codon types characterize typically the vertebrate mitochondrial genome. The determination of O. alticorpus mitogenome would play an important role not only in the delineation of phylogeographic history and population genetic structure, but reflection of conservation efforts on the genetic diversity as well as population vitality.
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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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DNA topoisomerase II is involved in regulation of cyst wall protein genes and differentiation in Giardia lamblia.
PLoS Negl Trop Dis
PUBLISHED: 05-01-2013
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The protozoan Giardia lamblia differentiates into infectious cysts within the human intestinal tract for disease transmission. Expression of the cyst wall protein (cwp) genes increases with similar kinetics during encystation. However, little is known how their gene regulation shares common mechanisms. DNA topoisomerases maintain normal topology of genomic DNA. They are necessary for cell proliferation and tissue development as they are involved in transcription, DNA replication, and chromosome condensation. A putative topoisomerase II (topo II) gene has been identified in the G. lamblia genome. We asked whether Topo II could regulate Giardia encystation. We found that Topo II was present in cell nuclei and its gene was up-regulated during encystation. Topo II has typical ATPase and DNA cleavage activity of type II topoisomerases. Mutation analysis revealed that the catalytic important Tyr residue and cleavage domain are important for Topo II function. We used etoposide-mediated topoisomerase immunoprecipitation assays to confirm the binding of Topo II to the cwp promoters in vivo. Interestingly, Topo II overexpression increased the levels of cwp gene expression and cyst formation. Microarray analysis identified up-regulation of cwp and specific vsp genes by Topo II. We also found that the type II topoisomerase inhibitor etoposide has growth inhibition effect on Giardia. Addition of etoposide significantly decreased the levels of cwp gene expression and cyst formation. Our results suggest that Topo II has been functionally conserved during evolution and that Topo II plays important roles in induction of the cwp genes, which is key to Giardia differentiation into cysts.
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Gender differences in renal transplant graft survival.
J. Formos. Med. Assoc.
PUBLISHED: 04-01-2013
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A long-term retrospective study was conducted to assess the risk factors of renal transplant graft failure focusing on the effects of gender of both the donor and the recipient.
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Long-term effects of prophylactic and therapeutic lamivudine treatments in hepatitis B surface antigen-positive renal allograft recipients.
Clin. Exp. Nephrol.
PUBLISHED: 02-05-2013
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BACKGROUND: Among hepatitis B surface antigen (HBsAg)-positive renal allograft recipients, post-transplant immunosuppression is associated with the occurrence of hepatocellular carcinoma (HCC) and liver-related complications. Lamivudine has proven beneficial in short-term post-transplant follow-up. METHODS: Between 2000 and 2009, 26 adult HBsAg-positive renal allograft recipients received lamivudine prophylaxis (Group 1) and another 28 patients received therapeutic lamivudine (Group 2) due to post-transplant hepatitis B reactivation. The historical control group included 43 HBsAg-positive renal allograft recipients who did not receive lamivudine therapy (Group 3). RESULTS: No subjects in Group 1 presented HCC or liver-related complications and the 10-year HCC incidence of Group 2 and Group 3 was 4.2 and 34 %, respectively. Furthermore, the HCC-free survival rates as well as the 10-year patient and graft survival rates of Group 1 and Group 2 were significantly higher than those of Group 3. However, the rates of liver-related complications and graft rejection of Group 2 and Group 3 were both higher than those of Group 1. Additionally, the HBV mutation-free rate of lamivudine was significantly higher in Group 1 than in Group 2. CONCLUSIONS: Lamivudine antiviral treatment, either on a prophylactic or therapeutic basis, provided long-term benefits for HBsAg-positive renal allograft recipients, in terms of reducing the occurrence of HCC and prolonging patient and graft survival. Furthermore, compared with therapeutic lamivudine, lamivudine prophylaxis appears to significantly reduce the incidence of liver-related complications, graft rejection, and lamivudine resistance.
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Anti-Bladder-Tumor Effect of Baicalein from Scutellaria baicalensis Georgi and Its Application In Vivo.
Evid Based Complement Alternat Med
PUBLISHED: 01-22-2013
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Some phytochemicals with the characteristics of cytotoxicity and/or antimetastasis have generated intense interest among the anticancer studies. In this study, a natural flavonoid baicalein was evaluated in bladder cancer in vitro and in vivo. Baicalein inhibits 5637 cell proliferation. It arrests cells in G1 phase at 100? ? M and in S phase below 75? ? M. The protein expression of cyclin B1 and cyclin D1 is reduced by baicalein. Baicalein-induced p-ERK plays a minor role in cyclin B1 reduction. Baicalein-inhibited p65NF- ? B results in reduction of cell growth. Baicalein-induced pGSK(ser9) has a little effect in increasing cyclin B1/D1 expression instead. The translation inhibitor cycloheximide blocks baicalein-reduced cyclin B1, suggesting that the reduction is caused by protein synthesis inhibition. On the other hand, neither cycloheximide nor proteasome inhibitor MG132 completely blocks baicalein-reduced cyclin D1, suggesting that baicalein reduces cyclin D1 through protein synthesis inhibition and proteasomal degradation activation. In addition, baicalein also inhibits cell invasion by inhibiting MMP-2 and MMP-9 mRNA expression and activity. In mouse orthotopic bladder tumor model, baicalein slightly reduces tumor size but with some hepatic toxicity. In summary, these results demonstrate the anti-bladder-tumor properties of the natural compound baicalein which shows a slight anti-bladder-tumor effect in vivo.
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A novel vertical fan-out platform based on an array of curved anodic alumina nanochannels.
Nanotechnology
PUBLISHED: 01-16-2013
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Focused ion beam lithography and a two-step anodization have been combined to fabricate a vertical fan-out platform containing an array of unique probes. Each probe comprises three anodic alumina nanochannels with a fan-out arrangement. The lithography is used to pattern an aluminum sheet with a custom-designed array of triangular cells whose apexes are composed of nanoholes. The nanoholes grow into straight nanochannels under proper voltage in the first-step anodization. The second step uses a doubled voltage to induce lateral repulsion among the nanochannels growth fronts originating in the same cell. Therefore, the fronts fan out. The repulsion roots in the inter-front distance being shorter than the naturally favoured length, which increases with anodization voltage. The fan-out evolution continues until the growth fronts originating in all the cells evolve into a close-packed two-dimensional hexagonal lattice whose spacing is identical to the favoured one. The chemical and physical mechanisms behind the fan-out fabrication are discussed. This novel fan-out platform facilitates probing and handling of many signals from different areas on a samples surface and is therefore promising for applications in detection and manipulation at the nanoscale level.
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The impact of polymorphisms in STAT6 on treatment outcome in HCV infected Taiwanese Chinese.
BMC Immunol.
PUBLISHED: 01-08-2013
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Genetic polymorphisms observed in various disease states associated with sensitivity or resistance to specific treatments have been a robust area of investigation for decades, with the potential to allow clinicians to make evidence-based decisions on the appropriate course of treatment. This study aimed to evaluate whether genetic polymorphisms of the signal transducer and activator of transcription 6 gene (STAT6) could be associated with a sustained virological response (SVR) among patients infected with hepatitis C virus genotypes 1 and 2 (HCV-1 and HCV-2) who were treated with peginterferon plus ribavirin (PEG-IFN?-RBV). We analyzed the associations between SVR to PEG-IFN?-RBV therapy and 4 single nucleotide polymorphisms (SNPs) in STAT6. This study included Taiwanese Chinese patients infected with either HCV-1 (n?=?265) or HCV-2 (n?=?195) in the presence or absence of an SVR. Among the STAT6 SNPs examined, the dosage effect of the A allele and allele frequency in rs1059513 were inversely correlated with SVR in patients infected with HCV-1 (P?=?0.0179 and P?=?0.0235, respectively). This effect was not observed in patients infected with HCV-2. The GG, GGG, and GGGC STAT6 haplotypes comprising 2, 3, and 4 SNPs (rs1059513, rs703817, rs324015, and rs3024974) were found to be associated with SVR, and their presence may increase the probability of a successful treatment outcome in patients infected with HCV-1 (P?=?0.0273, 0.0352, and 0.0368, respectively). Moreover, a multivariate logistic regression model for predicting an SVR revealed that the presence of the GGGC haplotype carriers mutually affected the outcome of PEG-IFN?-RBV treatment. The presence of STAT6 SNPs and the association with SVR demonstrated that STAT6 polymorphisms might influence the therapeutic outcomes of patients infected with HCV-1 under standard-of-care (SOC) treatment.
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Lingual leiomyomatous hamartoma with bifid tip and ankyloglossia in a patient without oral-facial-digital syndrome: a case report and literature review.
World J Surg Oncol
PUBLISHED: 01-04-2013
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Here is a rare case of lingual leiomyomatous hamartoma (LLH) with bifid tongue tip and tongue-tie in a patient with non-oral-facial-digital syndrome (OFDS). A 29-year-old male consulted for a painless tumor over the midline of the tongue dorsum measuring 2?×?1.5 cm. The tumor was excised and the tongue-tie was corrected. Diagnosis of LLH was based on histo-pathologic and immuno-histochemical studies. The epidemiologic data and differential diagnosis of LLH, as well as related literature, are discussed. To date, only 14 cases of LLH have been reported in English literature. This may be the first reported case of LLH with bifid tip and ankyloglossia in a non-OFDS patient.
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Serum oxidized albumin and cardiovascular mortality in normoalbuminemic hemodialysis patients: a cohort study.
PLoS ONE
PUBLISHED: 01-01-2013
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Substantial evidence suggests that increased oxidative stress in hemodialysis (HD) patients may contribute to cardiovascular complications. Oxidative modifications of human serum albumin (HSA), the largest thiol pool in plasma, alter its biological properties and may affect its antioxidant potential in HD patients.
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QS-ZYX-1-61 induces apoptosis through topoisomerase II in human non-small-cell lung cancer A549 cells.
Cancer Sci.
PUBLISHED: 10-17-2011
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Agents that cause DNA damage have been widely used as anticancer drugs because DNA lesions can initiate DNA checkpoints that induce cell death. The results presented here indicate that QS-ZYX-1-61, a derivative of VP-16, was significantly more potent than VP-16 in suppressing the viability of A549 cells. Treatment of cells with QS-ZYX-1-61 led to a DNA damage response and a dramatic increase of apoptosis. Our results also suggest that QS-ZYX-1-61 may be a topoisomerase (topo) II targeting agent, as evidenced by relaxation assay and induction of reversible cleavable complexes. Moreover, blocking of p53, topo II?, and topo II? greatly protected against caspase-3 activation, poly-ADP-ribose polymerase cleavage, and cell growth inhibition, indicating that QS-ZYX-1-61 acts through these proteins. These results support our conclusion that QS-ZYX-1-61 has potential as an anticancer agent because it causes accumulation of DNA cleavable complexes, with downstream consequences that include double-strand breaks and DNA damage response signaling for apoptosis. Taken together, our results indicate that QS-ZYX-1-61 is a novel DNA damaging agent and displays an outstanding activity that could be worthy of further investigation.
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Anuric acute renal failure after elective abortion.
Intern. Med.
PUBLISHED: 08-15-2011
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Elective abortion complicated by bilateral renal cortical necrosis (BRCN) is not common in a developed country. We reported a patient having anuric acute renal failure after elective abortion. Initial laboratory studies implied thrombotic thrombocytopenic purpura/Hemolytic uremic syndrome, but plasma exchange was not prescribed since magnetic resonance imaging study suggested BRCN soon after. The patient was treated as septic abortion and reached partial renal recovery after antibiotic treatment and short-term hemodialysis. Early diagnosis of BRCN is essential not only for prognosis prediction but also for treatment decision. We suggest that any anuric patient in suspicion of BRCN should receive MRI study as soon as possible.
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Design, fabrication and characterization of indefinite metamaterials of nanowires.
Philos Trans A Math Phys Eng Sci
PUBLISHED: 08-03-2011
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Indefinite optical properties, which are typically characterized by hyperbolic dispersion relations, have not been observed in naturally occurring materials, but can be realized through a metamaterial approach. We present here the design, fabrication and characterization of nanowire metamaterials with indefinite permittivity, in which all-angle negative refraction of light is observed. The bottom-up fabrication technique, which applies electrochemical plating of nanowires in porous alumina template, is developed and demonstrated in achieving uniform hyperbolic optical properties at a large scale. We developed techniques to improve the uniformity and to reduce the defect density in the sample. The non-magnetic design and the off-resonance operation of the nanowire metamaterials significantly reduce the energy loss of electromagnetic waves and make the broad-band negative refraction of light possible.
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Structural basis of type II topoisomerase inhibition by the anticancer drug etoposide.
Science
PUBLISHED: 07-23-2011
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Type II topoisomerases (TOP2s) resolve the topological problems of DNA by transiently cleaving both strands of a DNA duplex to form a cleavage complex through which another DNA segment can be transported. Several widely prescribed anticancer drugs increase the population of TOP2 cleavage complex, which leads to TOP2-mediated chromosome DNA breakage and death of cancer cells. We present the crystal structure of a large fragment of human TOP2? complexed to DNA and to the anticancer drug etoposide to reveal structural details of drug-induced stabilization of a cleavage complex. The interplay between the protein, the DNA, and the drug explains the structure-activity relations of etoposide derivatives and the molecular basis of drug-resistant mutations. The analysis of protein-drug interactions provides information applicable for developing an isoform-specific TOP2-targeting strategy.
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Molecular basis of the recognition of the ap65-1 gene transcription promoter elements by a Myb protein from the protozoan parasite Trichomonas vaginalis.
Nucleic Acids Res.
PUBLISHED: 07-19-2011
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Iron-inducible transcription of the ap65-1 gene in Trichomonas vaginalis involves at least three Myb-like transcriptional factors (tvMyb1, tvMyb2 and tvMyb3) that differentially bind to two closely spaced promoter sites, MRE-1/MRE-2r and MRE-2f. Here, we defined a fragment of tvMyb2 comprising residues 40-156 (tvMyb2??????) as the minimum structural unit that retains near full binding affinity with the promoter DNAs. Like c-Myb in vertebrates, the DNA-free tvMyb2?????? has a flexible and open conformation. Upon binding to the promoter DNA elements, tvMyb2?????? undergoes significant conformational re-arrangement and structure stabilization. Crystal structures of tvMyb2?????? in complex with promoter element-containing DNA oligomers showed that 5-a/gACGAT-3 is the specific base sequence recognized by tvMyb2??????, which does not fully conform to that of the Myb binding site sequence. Furthermore, Lys??, which is upstream of the R2 motif (amino acids 52-102) also participates in specific DNA sequence recognition. Intriguingly, tvMyb2?????? binds to the promoter elements in an orientation opposite to that proposed in the HADDOCK model of the tvMyb1??????/MRE-1-MRE-2r complex. These results shed new light on understanding the molecular mechanism of Myb-DNA recognition and provide a framework to study the molecular basis of transcriptional regulation of myriad Mybs in T. vaginalis.
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Functionalized arrays of Raman-enhancing nanoparticles for capture and culture-free analysis of bacteria in human blood.
Nat Commun
PUBLISHED: 07-01-2011
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Detecting bacteria in clinical samples without using time-consuming culture processes would allow rapid diagnoses. Such a culture-free detection method requires the capture and analysis of bacteria from a body fluid, which are usually of complicated composition. Here we show that coating Ag-nanoparticle arrays with vancomycin (Van) can provide label-free analysis of bacteria via surface-enhanced Raman spectroscopy (SERS), leading to a ~1,000-fold increase in bacteria capture, without introducing significant spectral interference. Bacteria from human blood can be concentrated onto a microscopic Van-coated area while blood cells are excluded. Furthermore, a Van-coated substrate provides distinctly different SERS spectra of Van-susceptible and Van-resistant Enterococcus, indicating its potential use for drug-resistance tests. Our results represent a critical step towards the creation of SERS-based multifunctional biochips for rapid culture- and label-free detection and drug-resistant testing of microorganisms in clinical samples.
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Identification of Rickettsia felis in fleas but not ticks on stray cats and dogs and the evidence of Rickettsia rhipicephali only in adult stage of Rhipicephalus sanguineus and Rhipicephalus haemaphysaloides.
Comp. Immunol. Microbiol. Infect. Dis.
PUBLISHED: 06-29-2011
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Rickettsia spp. are zoonotic pathogens and mainly transmitted by various arthropod vectors, such as fleas, ticks, and lice. Previous epidemiological studies indicated that ectoparasites infested on dogs or cats may be infected by Rickettsia spp., and transmit them to human beings accidentally. In this study, the prevalence of Rickettsia infection was evaluated using fleas and ticks from stray dogs and cats in Taiwan. A total of 158 pools made by 451 cat fleas (Ctenocephalides felis) from 37 dogs and 4 cats were used for analysis. Besides, 386 Rhipicephalus ticks collected from the other 62 stray dogs were included in this study. Nymphal and adult ticks were individually analyzed but larvae were separated into 21 pools for molecular detection. Partial sequencing analysis of the gltA gene was applied for Rickettsia identification. The results showed that 44.3% (70/158) of the cat flea pools were harboring Rickettsia DNA. Although 6.9% (13/187) of adult ticks were infected with Rickettsia, neither larval pools nor nymphal ticks were found to contain Rickettsia DNA. According to the results of sequencing analyses, all Rickettsia PCR-positive cat flea pools were infected with R. felis, and all Rickettsia PCR-positive adult ticks were infected with R. rhipicephali. The results of this study demonstrated that C. felis but not Rhipicephlus sanguineus (the brown dog tick) and Rh. haemaphysaloides collected from stray animals in Taiwan could be infected the zoonotic pathogen R. felis. Moreover, R. rhipicephali was only identified in adult stage of Rhipicephalus sanguineus and Rh. haemaphysaloides.
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Mitoxantrone inhibits HIF-1? expression in a topoisomerase II-independent pathway.
Clin. Cancer Res.
PUBLISHED: 06-08-2011
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Solid tumors encounter a growth-limiting hypoxic microenvironment as they develop. Hypoxia-inducible factors (HIF) play important roles in hypoxia-associated tumor development and therapeutic resistance. Targeting the HIF pathway (especially HIF-1?) represents a promising cancer treatment strategy. Here, we report a novel class of HIF-1? inhibitors and the possible molecular basis of inhibition.
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In vivo 1H MRS for musculoskeletal lesion characterization: which factors affect diagnostic accuracy?
NMR Biomed
PUBLISHED: 05-27-2011
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In vivo (1)H MRS is a noninvasive imaging technique for the identification of malignancy. Musculoskeletal lesions vary in their composition, causing field inhomogeneity and magnetic susceptibility effects which may be technical and diagnostic challenges for MRS. This study investigated the factors that affect diagnostic accuracy in the use of MRS for the characterization of musculoskeletal neoplasms. During a 7-year period, 210 consecutive patients with musculoskeletal lesions larger than 1.5?cm in diameter were examined. MRS of a single-voxel point-resolved spectroscopy sequence with TE?=?135?ms was undertaken using a 1.5-T scanner. Lesions with a choline signal-to-noise ratio larger than 3.0 were considered to be malignant tumors. The diagnostic accuracy was calculated for all lesions and for subgroups on the basis of lesion type (bone and soft tissue), lesion composition (mixed and solid nonsclerotic), lesion size (?4, >4-10 and >10?cm), MR scanner (MR scanner 1 and 2) and selected voxel size (?3, >3-8 and >8?cm(3)). Multivariate logistic regressions were performed to estimate the associations between each factor and diagnostic accuracy. The diagnostic accuracy was 73.3% for all lesions. The accuracy was 54.4% for mixed lesions and 80.4% for solid nonsclerotic lesions (p?4-10?cm (p?=?0.04) and 63.6% for lesions of >10?cm (p?=?0.007)]. There was no difference in diagnostic accuracy for bone versus soft-tissue lesions or as a function of MR scanner or voxel size. By the use of multivariate logistic regression, a solid nonsclerotic lesion was 3.15 times (95% confidence interval, 1.59-6.27) more likely than a mixed lesion to have a diagnosis (p?=?0.001). MRS can be used to characterize musculoskeletal lesions, particularly solid nonsclerotic lesions.
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Prevalence of Rickettsia felis and the first identification of Bartonella henselae Fizz/CAL-1 in cat fleas (Siphonaptera: Pulicidae) from Taiwan.
J. Med. Entomol.
PUBLISHED: 04-13-2011
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Cat fleas (Ctenocephalides felis [Bouché]) are the primary ectoparasites of dog and cat populations. In this study, we report the monthly population dynamics of Rickettsia felis and Bartonella spp. (two zoonotic pathogens that can cause human disease) in cat fleas collected from dogs and cats in Taipei, Taiwan, from December 2006 to December 2007. Natural R. felis infection in individual cat fleas was assessed by polymerase chain reaction (PCR) using pRF-, ompB-, and gltA-specific primer pairs. Samples positive by PCR were confirmed with DNA sequencing. R. felis was detected in cat fleas year round, and the average infection rate was 21.4% (90 of 420) in 2007. Cat fleas also play an important role in the transmission of Bartonella between reservoirs and other mammalian hosts. In this study, we used primer pairs specific for the Bartonella gltA and rpoB genes to detect Bartonella infections. Of the 420 cat fleas tested, 38 were positive by PCR for Bartonella. Sequence similarities to Bartonella henselae, Bartonella clarridgeiae, and Bartonella koehlerae were observed in 6.2% (26 of 420), 2.1% (9 of 420), and 0.7% (3 of 420) of the fleas, respectively. Based on the pap31 gene sequence, several amplicons of the B. henselae detected in the cat fleas could be subgrouped into three strains: Fizz/CAL-1 (n = 18), Marseille (n = 5), and Houston-1 (n = 3). These results demonstrate that cat fleas infected with R. felis are endemic to Taiwan, and highlight the role of C. felis in Bartonella transmission between reservoirs and other mammal hosts and demonstrate the genetic variability of B. henselae in Taiwan.
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Ellagic acid inhibits oxidized low-density lipoprotein (OxLDL)-induced metalloproteinase (MMP) expression by modulating the protein kinase C-?/extracellular signal-regulated kinase/peroxisome proliferator-activated receptor ?/nuclear factor-?B (PKC-?/ERK/
J. Agric. Food Chem.
PUBLISHED: 04-11-2011
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Previous studies have shown that vascular endothelium-derived matrix metalloproteinases (MMPs) contribute to the destabilization of atherosclerotic plaques, a key event triggering acute myocardial infarction. In addition, studies have reported that the PKC-MEK-PPAR? signaling pathway is involved in oxidized low-density lipoprotein (oxLDL)-induced expression of MMPs. Ellagic acid, a phenolic compound found in fruits and nuts, has potent antioxidant, anti-inflammatory, and anticancerous properties. However, the molecular mechanisms underlying its antiatherogenic effects remain to be clarified. This study aimed to assess whether the effects of ellagic acid on the fibrotic markers MMP-1 and MMP-3 are modulated by the PKC-ERK-PPAR-? signaling pathway in human umbilical vein endothelial cells (HUVECs) that have been exposed to oxLDL. It was found that ellagic acid significantly inhibited oxLDL-induced expressions of MMP-1 and MMP-3. Pretreatment with ellagic acid and DPI, a well-known ROS inhibitor, attenuated the oxLDL-induced expression and activity of PKC-?. In addition, ellagic acid as well as pharmacological inhibitors of ROS, calcium, and PKC strongly suppressed the oxLDL-induced phosphorylation of extracellular signal-regulated kinase (ERK) and NF-?B activation. Moreover, ellagic acid ameliorated the oxLDL-induced suppression of PPAR-? expression. In conclusion, the data suggest that ellagic acid elicits its protective effects by modulating the PKC-?/ERK/PPAR-?/NF-?B pathway, resulting in the suppression of ROS generation and, ultimately, inhibition of MMP-1 and MMP-3 expression in HUVECs exposed to oxLDL.
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Impact localization combined with haptic feedback for touch panel applications based on the time-reversal approach.
J. Acoust. Soc. Am.
PUBLISHED: 03-25-2011
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In this paper, a combined impact localization and haptic feedback system based on time-reversal signal processing is presented for touch panel applications. Theoretical impulse responses are derived from a propagation model of bending waves in a thin elastic plate. On the basis of the impulse responses, the time-reversal technique is exploited to spot the impact location as well as to generate haptic feedback. The chief advantage of the time-reversal technique lies in its robustness of tackling broadband sources in a reverberant environment. Piezoelectric ceramic plates and voice-coil motors are used as sensors for localization, whereas only voice-coil motors are used as the actuator for haptic feedback. Experimental results demonstrated that the proposed system was effective in precise impact localization for a thin panel, while haptic feedback also implemented using time-reversal principle can generate an impulse at the previously touched position. The combined impact localization and haptic feedback system is capable of enhancing the sensation of man-machine interaction in real time fashion.
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Comparison of an electrochemical biosensor with optical devices for hemoglobin measurement in human whole blood samples.
Clin. Chim. Acta
PUBLISHED: 03-09-2011
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An electrochemical based biosensor for hemoglobin measurement was developed as an alternative to the traditional optical method, and underwent testing for use in professional settings.
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Coenzyme Q10 suppresses oxLDL-induced endothelial oxidative injuries by the modulation of LOX-1-mediated ROS generation via the AMPK/PKC/NADPH oxidase signaling pathway.
Mol Nutr Food Res
PUBLISHED: 03-04-2011
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The lectin-like oxidized low-density lipoprotein receptor (LOX-1) is one pivot receptor for oxidized low-density lipoprotein (oxLDL) in human endothelial cells. Co-enzyme Q10 (Co Q10) has been widely used in clinical intervention. However, the molecular mechanisms underlying its protective effects against oxidative stress in endothelial cells are still largely unknown. This study was designed to test the hypothesis that Co Q10 mitigates oxLDL-induced endothelial oxidative injuries via modulation of LOX-1-mediated reactive oxygen species (ROS) generation and explored the role of AMP-activated protein kinase (AMPK), a negative regulator of NADPH oxidase.
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Reflux esophagitis and marginal ulcer after pancreaticoduodenectomy.
J. Gastrointest. Surg.
PUBLISHED: 02-02-2011
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Reflux esophagitis is a common complication following a distal gastrectomy. Increasingly, Roux-en-Y reconstruction has been used to prevent reflux esophagitis; however, marginal ulcer is a concern in patients with a Roux-en-Y reconstruction after distal gastrectomy. The effect of Roux-en-Y reconstruction on the development of reflux esophagitis and marginal ulcer after pancreaticoduodenectomy (PD) has not been studied.
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Change in hepatitis A epidemiology after vaccinating high risk children in Taiwan, 1995-2008.
Vaccine
PUBLISHED: 01-31-2011
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Taiwan started to immunize children in 30 indigenous townships against hepatitis A since June 1995. The program was further expanded to 19 non-indigenous townships with higher incidence or increased risk of epidemic in 1997-2002, covering 2% of total population. Annual incidence of hepatitis A decreased from 2.96 in 1995 (baseline period) to 0.90/100,000 in 2003-2008 (vaccination period). The incidence in vaccinated townships and unvaccinated townships declined 98.3% (49.66-0.86/100,000) and 52.6% (1.90-0.90/100,000). In 2003-2008, incidence doubled in people aged >=30 years, mostly in unvaccinated townships (0.42-0.92). During 2003-2008, travel to endemic countries was the most commonly reported risk factor (13.5%). First dose vaccine coverage was 78.8% in 1994-2005 birth cohort. Taiwans experience demonstrates the great, long-term efficacy of hepatitis A vaccine in disease control in vaccinated townships, and out-of-cohort effect in unvaccinated townships. Further reduction can be achieved by improving vaccination coverage of adults at risk.
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De novo malignancy is associated with renal transplant tourism.
Kidney Int.
PUBLISHED: 01-26-2011
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Despite the objections to transplant tourism raised by the transplant community, many patients continue travel to other countries to receive commercial transplants. To evaluate some long-term complications, we reviewed medical records of 215 Taiwanese patients (touring group) who received commercial cadaveric renal transplants in China and compared them with those of 321 transplant recipients receiving domestic cadaveric renal transplants (domestic group) over the same 20-year period. Ten years after transplant, the graft and patient survival rates of the touring group were 55 and 81.5%, respectively, compared with 60 and 89.3%, respectively, of the domestic group. The difference between the two groups was not statistically significant. The 10-year cumulative cancer incidence of the touring group (21.5%) was significantly higher than that of the domestic group (6.8%). Univariate and multivariate stepwise regression analyses (excluding time on immunosuppression, an uncontrollable factor) indicated that transplant tourism was associated with significantly higher cancer incidence. Older age at transplantation was associated with a significantly increased cancer risk; however, the risk of de novo malignancy significantly decreased with longer graft survival. Thus, renal transplant tourism may be associated with a higher risk of post-transplant malignancy, especially in patients of older age at transplantation.
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A novel mechanism of coenzyme Q10 protects against human endothelial cells from oxidative stress-induced injury by modulating NO-related pathways.
J. Nutr. Biochem.
PUBLISHED: 01-22-2011
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Atherosclerosis is a chronic inflammatory disease of the vessel wall associated with oxidized low-density lipoprotein (oxLDL)-induced apoptosis of endothelial cells. Coenzyme Q10 (CoQ10), a potent antioxidant and a critical intermediate of the electron transport chain, has been reported to inhibit LDL oxidation and thus the progression of atherosclerosis. However, its molecular mechanisms on endothelial cells remain still unclarified.
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Influenza genome diversity and evolution.
Microbes Infect.
PUBLISHED: 01-18-2011
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The influenza viruses contain highly variable genomes and are able to infect a wide range of host species. Large-scale sequencing projects have collected abundant influenza sequence data for assessing influenza genome diversity and evolution. This work reviews current influenza sequence databases characteristics and statistics, as well as recent studies utilizing these databases to unravel influenza virus diversity and evolution. Also discussed are the newest deep sequencing methods and their applications to influenza virus research.
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Bartonella infection in shelter cats and dogs and their ectoparasites.
Vector Borne Zoonotic Dis.
PUBLISHED: 12-13-2010
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Mainly through vector transmission, domestic cats and dogs are infected by several Bartonella spp. and represent a large reservoir for human infections. This study investigated the relationship of prevalences of Bartonella infection in shelter dogs and cats and various ectoparasite species infesting them (fleas, ticks, and lice). Moreover, relationships between Bartonella infection and animal gender and age and presence of ectoparasites were analyzed. Blood samples were collected from 120 dogs and 103 cats. There were 386 ticks and 36 fleas harvested on these dogs, and 141 fleas, 4 ticks, and 2 lice harvested on these cats. Isolation/detection of Bartonella sp. was performed by culture, polymerase chain reaction (PCR), and partial sequencing. Bartonella was isolated from 21 (20.4%) cats and detected by PCR from 20 (19.4%) cats, 2 (1.7%) dogs, 55 (39%) fleas collected from cats, 28 (10%) ticks DNA samples, and 1 (2.8%) flea collected from dogs. When combining culture and PCR data, 27 cats and 55 fleas collected on cats were positive for Bartonella henselae or Bartonella clarridgeiae, but none were coinfected. Approximately half of the B. henselae isolates from 21 cats were B. henselae type I. Moreover, B. henselae, Bartonella phoceensis, Bartonella queenslandensis, Bartonella rattimassiliensis, Bartonella elizabethae DNA was detected in ticks collected from dogs and one flea was B. clarridgeiae PCR positive. This is the first report of such a wide variety of Bartonella spp. detected in Rhipicephalus sanguineus. Further studies are required to understand the relative importance of these ectoparasites to transmit Bartonella spp. in dogs and cats.
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Identical-length nanowire arrays in anodic alumina templates.
J Nanosci Nanotechnol
PUBLISHED: 12-03-2010
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Arrays of nanowires with identical length are fabricated by using ultrasound to remove the length fluctuation among nanowires, which are deliberately grown in burette-shaped nanochannels on an anodic anumina film. The process allows the fabrication of 10 micron Ag-nanowire arrays with length fluctuation as small as 0.09%. By integrating the process with a focused-ion-beam-based lithographic method to grow nanowires into selective nanochannels in an array, we fabricate arrays of uniform-length nanowires that are arranged in a custom-designed lateral geometry. The ability to fabricate such artificial nanomaterials paves the way for the exploitation of their unusual optical, electrical, and thermal properties.
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Phylogenetic analysis of 56-kDa type-specific antigen gene of Orientia tsutsugamushi isolates in Taiwan.
Am. J. Trop. Med. Hyg.
PUBLISHED: 09-03-2010
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Scrub typhus is a rickettsial disease transmitted to humans through the bite of chigger mites infected with Orientia tsutsugamushi, and is an endemic disease in Taiwan. To elucidate the molecular epidemiology of O. tsutsugamushi, the complete open reading frame of the 56-kDa type-specific antigen gene sequence of strains isolated from scrub typhus patients were determined and analyzed. A total of 116 isolates of O. tsutsugamushi were successfully isolated from patients infected in diverse geographic origins including Taiwan and three offshore islets, Kinmen, Matsu, and Penghu between May 2006 and December 2007. Sequence analysis revealed that 22 distinct sequence types could be identified that were broadly distributed in different clusters of the phylogenetic tree. Most of the isolates belong to Karp, Kawasaki, and Kuroki genotypes and are closely related to strains from Thailand, Japan, and Korea, whereas unique isolates different from other countries were also found in Taiwan. Distinct seasonal distributions were found in different sequence types. Some sequence types caused disease in the cold season, whereas others caused disease in the warm season.
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Ileoileal intussusception due to ileal ectopic pancreas with abundant fat tissue mimicking lipoma.
Am. J. Surg.
PUBLISHED: 08-04-2010
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A 26-year-old woman presented with symptoms of bowel obstruction. An emergent computed tomography (CT) scan was performed which showed ileoileal intussusceptions due to a fatty nodule. Exploratory laparotomy and removal of the involved small bowel was performed. The pathology showed the leading point of the intussusception to be ectopic pancreas with abundant fatty infiltration.
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EGF-induced Grb7 recruits and promotes Ras activity essential for the tumorigenicity of Sk-Br3 breast cancer cells.
J. Biol. Chem.
PUBLISHED: 07-09-2010
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Co-amplification and co-overexpression of ErbB2 and Grb7 are frequently found in various cancers, including breast cancer. Biochemical and functional correlations of the two molecules have identified Grb7 to be a pivotal mediator downstream of ErbB2-mediated oncogenesis. However, it remains largely unknown how Grb7 is involve in the ErbB2-mediated tumorigenesis. In this study, we show that Grb7-mediated cell proliferation and growth are essential for the tumorigenesis that occurs in ErbB2-Grb7-overexpressing breast cancer cells. Intrinsically, EGF-induced de novo Grb7 tyrosine phosphorylation/activation recruits and activates Ras-GTPases and subsequently promotes the phosphorylation of ERK1/2, thereby stimulating tumor growth. Furthermore, we also found the anti-tumor effect could be synergized by co-treatment with Herceptin plus Grb7 knockdown in Sk-Br3 breast cancer cells. Our findings illustrate an underlying mechanism by which Grb7 promotes tumorigenesis through the formation of a novel EGFR-Grb7-Ras signaling complex, thereby highlighting the potential strategy of targeting Grb7 as an anti-breast cancer therapy.
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Cellular processing determinants for the activation of damage signals in response to topoisomerase I-linked DNA breakage.
Cell Res.
PUBLISHED: 07-06-2010
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Recent studies have suggested an involvement of processing pathways for the initiation of cellular responses induced by topoisomerase-targeting drugs. Here, we showed that cellular exposure to camptothecin (CPT) induced formation of topoisomerase I cleavable complex (TOP1cc), degradation of TOP1 and activation of DNA damage responses (DDR). Transcription and proteasome-dependent proteolysis, but not replication, were involved in CPT-induced TOP1 degradation, while none of above three processing activities affected TOP1cc formation. Replication- and transcription-initiated processing (RIP and TIP) of TOP1cc were identified as two independent pathways, which contribute distinctly to various CPT-activated DDR. Specifically, in cycling cells, RIP-processed TOP1cc triggered the CPT-induced RPA phosphorylation. At higher CPT dosages, the TIP pathway is required for other DDR activation, including ATM, p53 and Chk1/2 phosphorylation. The TIP pathway was further demonstrated to be S-phase independent by using three nonreplicating cell models. Furthermore, the effect of proteasome inhibitors mimicked that of transcription inhibition on the CPT-induced activation of DDR, suggesting the involvement of proteasome in the TIP pathway. Interestingly, the TIP pathway was important for TOP1cc-activated, but not ionization radiation-activated ATM, p53 and Chk2 phosphorylation. We have also found that pharmacological interferences of TIP and RIP pathways distinctively modulated the CPT-induced cell killing with treatments at low and high dosages, respectively. Together, our results support that both RIP and TIP pathways of TOP1cc are required for the activation of CPT-induced DDR and cytotoxicity.
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The role of imported cases and favorable meteorological conditions in the onset of dengue epidemics.
PLoS Negl Trop Dis
PUBLISHED: 06-24-2010
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Travelers who acquire dengue infection are often routes for virus transmission to other regions. Nevertheless, the interplay between infected travelers, climate, vectors, and indigenous dengue incidence remains unclear. The role of foreign-origin cases on local dengue epidemics thus has been largely neglected by research. This study investigated the effect of both imported dengue and local meteorological factors on the occurrence of indigenous dengue in Taiwan.
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Ellagic acid inhibits oxidized LDL-mediated LOX-1 expression, ROS generation, and inflammation in human endothelial cells.
J. Vasc. Surg.
PUBLISHED: 04-19-2010
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LOX-1, a lectin-like receptor on endothelial cells, facilitates the uptake of oxidized low-density lipoprotein (oxLDL). Expression of LOX-1 is involved in the pathobiological effects of oxLDL in endothelial cells, including reactive oxygen species (ROS) generation, suppression of endothelial nitric oxide synthase (eNOS) activity, and leukocytic adhesion. Moderate consumption of phenolic-enriched food may have a protective effect against the development of atherosclerosis via the antioxidant capacity of phenolic compounds at the endothelial level. In this study, we determined whether ellagic acid, a polyphenolic compound widely distributed in fruits and nuts, protects against oxLDL-induced endothelial dysfunction by modulating the LOX-1-mediated signaling pathway.
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Sodium salicylate acts through direct inhibition of phosphoinositide 3-kinase-like kinases to modulate topoisomerase-mediated DNA damage responses.
Eur. J. Pharmacol.
PUBLISHED: 04-04-2010
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Chemopreventive non-steroidal anti-inflammatory drugs (NSAIDs) exhibit diverse pharmacological and biological activities mainly through their inhibitory effect on cyclooxygenase (COX). However, COX-independent mechanisms involving kinase inhibition have been proposed to explain certain therapeutic effects of NSAIDs. Here, we explored the potential relationship between chemopreventive NSAIDs and DNA damage responses induced by treatment with topoisomerase-targeting drugs. (1) Sodium salicylate, a non-COX-selective NSAID, was shown to reduce DNA damage-induced RPA and p53 phosphorylation. (2) The formation of enzyme cleavable complexes by topoisomerase-targeting drugs was not affected in the presence of sodium salicylate. (3) The attenuating effect of NSAIDs on the DNA damage responses is COX-2-independent, since COX-2-selective inhibitors failed to inhibit DNA damage-induced phosphorylation of replication protein A (RPA) and p53. (4) This COX-2-independent attenuating effect was mediated through interference of neither nuclear factor kappa B nor extracellular signal-regulated kinase pathways. (5) The activation of ataxia telangiectasia mutated (ATM) kinase and DNA-dependent protein kinase (DNA-PK), two key signal transducers upstream of RPA and p53, was found to be significantly reduced with sodium salicylate treatment. (6) Most importantly, sodium salicylate and other NSAIDs directly inhibited kinase activity of ATM and DNA-PK. The extent of inhibition on the kinase activity also correlated with the degree of attenuation on the DNA damage responses. (7) Unexpectedly, sodium salicylate showed a p53-independent protection effect on topoisomerase-mediated cell killing. Together, our study provides evidence that NSAIDs exhibit a novel COX-independent modulating activity of NSAIDs on the DNA damage responses and it is through inhibition of phosphoinositide 3-kinase-like kinases.
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Calcium-induced cleavage of DNA topoisomerase I involves the cytoplasmic-nuclear shuttling of calpain 2.
Cell. Mol. Life Sci.
PUBLISHED: 03-31-2010
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Important to the function of calpains is temporal and spatial regulation of their proteolytic activity. Here, we demonstrate that cytoplasm-resident calpain 2 cleaves human nuclear topoisomerase I (hTOP1) via Ca(2+)-activated proteolysis and nucleoplasmic shuttling of proteases. This proteolysis of hTOP1 was induced by either ionomycin-caused Ca(2+) influx or addition of Ca(2+) in cellular extracts. Ca(2+) failed to induce hTOP1 proteolysis in calpain 2-knockdown cells. Moreover, calpain 2 cleaved hTOP1 in vitro. Furthermore, calpain 2 entered the nucleus upon Ca(2+) influx, and calpastatin interfered with this process. Calpain 2 cleavage sites were mapped at K(158) and K(183) of hTOP1. Calpain 2-truncated hTOP1 exhibited greater relaxation activity but remained able to interact with nucleolin and to form cleavable complexes. Interestingly, calpain 2 appears to be involved in ionomycin-induced protection from camptothecin-induced cytotoxicity. Thus, our data suggest that nucleocytoplasmic shuttling may serve as a novel type of regulation for calpain 2-mediated nuclear proteolysis.
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Folic acid-conjugated chitosan nanoparticles enhanced protoporphyrin IX accumulation in colorectal cancer cells.
Bioconjug. Chem.
PUBLISHED: 03-13-2010
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Folic acid can be covalently conjugated to chitosan molecules via its gamma-carboxyl moiety and thus retain a high affinity for colorectal cancer cells bearing folate receptor overexpression. Colorectal cancer is one of the leading causes of malignant death and often goes undetected with current colonoscopy practices. Improved methods of detecting dysplasia and tumors during colonoscopy will improve mortality. A folic acid conjugated chitosan nanoparticle as a suitable vehicle for carrying 5-aminolaevulinic acid (5-ALA) is developed to enhance the detection of colorectal cancer cells in vivo after a short-term uptake period. Chitosan can be successfully conjugated with folic acid to produce folic acid-chitosan conjugate, which is then loaded with 5-ALA to create nanoparticles (fCNA). The loading efficiency of 5-ALA in fCNA particles and the z-average diameter were in the range 35-40% and 100 nm, respectively. The zeta-potential for fCNA was 20 mV, enough to keep the nanoparticle stable without aggregation. The fCNA is then incubated with HT29 and Caco-2 colorectal cancer cell lines overexpressing folate receptor on the surface of the cell membrane to determine the rate of accumulation of protoporphyrin IX (PpIX). The results show that fCNA can be taken up more easily by HT29 and Caco-2 cell lines after short-term uptake period, most likely via receptor-mediated endocytosis, and the PpIX accumulates in cancer cells as a function of the folate receptor expression and the folic acid modification. Therefore, the folic acid-chitosan conjugate appears to be an ideal vector for colorectal-specific delivery of 5-ALA for fluorescent endoscopic detection.
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EGCG protects against oxidized LDL-induced endothelial dysfunction by inhibiting LOX-1-mediated signaling.
J. Appl. Physiol.
PUBLISHED: 03-04-2010
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Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), originally identified as the major receptor for oxidized low-density lipoprotein (oxLDL) in endothelial cells, plays a major role in the pathology of vascular diseases. Green tea consumption is associated with reduced cardiovascular mortality in some epidemiological studies. In the present study, we hypothesized that the most abundant polyphenolic compound in tea, epigallocatechin-3-gallate (EGCG), can downregulate parameters of endothelial dysfunction by modulating LOX-1-regulated cell signaling. In cultured human umbilical vein endothelial cells (HUVECs), exposure to oxLDL (130 microg/ml), which led to an increase in LOX-1 expression at the RNA and protein levels, was abrogated by addition of EGCG or DPI, a well-known inhibitor of flavoproteins, suggesting the involvement of NADPH oxidase. Furthermore, oxLDL rapidly activated the membrane translocation of Rac-1 and p47phox and the subsequent induction of ROS generation, which was suppressed markedly by pretreatment with EGCG or anti-LOX-1 monoclonal antibody. OxLDL also increased p38 MAPK phosphorylation and decreased phosphorylation of the amino-terminal region of Akt, with maximal induction at about 30 min, and NF-kappaB phosphorylation within 1 h, resulting in redox-sensitive signaling. In addition, oxLDL diminished the expression of endothelial nitric oxide synthase (eNOS), enhanced the expression of endothelin-1 and adhesion molecules (ICAM, E-selectin, and monocyte chemoattractant protein-1), and increased the adherence of monocytic THP-1 cells to HUVECs. Pretreatment with EGCG, however, exerted significant cytoprotective effects in all events. These data suggest that EGCG inhibits the oxLDL-induced LOX-1-mediated signaling pathway, at least in part, by inhibiting NADPH oxidase and consequent ROS-enhanced LOX-1 expression, which contributes to further ROS generation and the subsequent activation of NF-kappaB via the p38 MAPK pathway. Results from this study may provide insight into a possible molecular mechanism by which EGCG suppresses oxLDL-mediated vascular endothelial dysfunction.
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Longitudinal assessment of prognostic factors for patients with hepatorenal syndrome in a tertiary center.
Hepatol Int
PUBLISHED: 02-26-2010
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Hepatorenal syndrome (HRS) is one of the serious complications in patients with advanced cirrhosis and ascites. In tertiary centers, most patients were classified as having type 1 HRS for their rapid progressive diseases. However, no significant predictors have been assessed previously for patients with type 1 HRS. In addition to the initial model of end-stage liver disease (MELD) scores and biochemistry parameters, we want to further investigate the prognostic importance of changes in MELD scores and biochemistry parameters over time for patients with type 1 HRS.
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Ellagic acid protects endothelial cells from oxidized low-density lipoprotein-induced apoptosis by modulating the PI3K/Akt/eNOS pathway.
Toxicol. Appl. Pharmacol.
PUBLISHED: 02-11-2010
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Endothelial apoptosis is a driving force in atherosclerosis development. Oxidized low-density lipoprotein (oxLDL) promotes inflammatory and thrombotic processes and is highly atherogenic, as it stimulates macrophage cholesterol accumulation and foam cell formation. Previous studies have shown that the phosphatidylinositol 3-kinase/Akt/endothelial nitric oxide synthase/nitric oxide (PI3K/Akt/eNOS/NO) pathway is involved in oxLDL-induced endothelial apoptosis. Ellagic acid, a natural polyphenol found in berries and nuts, has in recent years been the subject of intense research within the fields of cancer and inflammation. However, its protective effects against oxLDL-induced injury in vascular endothelial cells have not been clarified. In the present study, we investigated the anti-apoptotic effect of ellagic acid in human umbilical vein endothelial cells (HUVECs) exposed to oxLDL and explored the possible mechanisms. Our results showed that pretreatment with ellagic acid (5-20?M) significantly attenuated oxLDL-induced cytotoxicity, apoptotic features, and generation of reactive oxygen species (ROS). In addition, the anti-apoptotic effect of ellagic acid was partially inhibited by a PI3K inhibitor (wortmannin) and a specific eNOS inhibitor (cavtratin) but not by an ERK inhibitor (PD98059). In exploring the underlying mechanisms of ellagic acid action, we found that oxLDL decreased Akt and eNOS phosphorylation, which in turn activated NF-?B and downstream pro-apoptotic signaling events including calcium accumulation, destabilization of mitochondrial permeability, and disruption of the balance between pro- and anti-apoptotic Bcl-2 proteins. Those alterations induced by oxLDL, however, were attenuated by pretreatment with ellagic acid. The inhibition of oxLDL-induced endothelial apoptosis by ellagic acid is due at least in part to its anti-oxidant activity and its ability to modulate the PI3K/Akt/eNOS signaling pathway.
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4-Chloro-3,5-dihydroxystilbene, a resveratrol derivative, induces lung cancer cell death.
Acta Pharmacol. Sin.
PUBLISHED: 01-06-2010
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To examine the antitumor effect of 4-chloro-3,5-dihydroxystilbene, a resveratrol derivative, on lung adenocarcinoma A549 cells.
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Low incidence of malignancy in heart-transplant recipients in Taiwan: an update and comparison with kidney-transplant recipients.
Eur J Cardiothorac Surg
PUBLISHED: 01-05-2010
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Malignancy is the leading cause of death among heart-transplant recipients. There is a higher incidence of post-transplant malignancy in heart-transplant recipients than in kidney-transplant recipients. This study sought to assess the incidence of malignancy in heart-transplant recipients in Taiwan.
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Intrarenal vascular resistance parameters in kidney transplant patients receiving calcineurin inhibitor-based or sirolimus-based regimens.
Nephrol. Dial. Transplant.
PUBLISHED: 12-29-2009
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Use of a calcineurin inhibitor (CNI) immunosuppressant following kidney transplantation is associated with development of vasomotor nephrotoxicity. This study was undertaken to evaluate and compare the influences of CNI-based and CNI-free immunosuppressant regimens on two intrarenal vascular resistance parameters, the resistive index (RI) and the pulsatility index (PI), in renal transplant recipients.
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Sesamin mitigates inflammation and oxidative stress in endothelial cells exposed to oxidized low-density lipoprotein.
J. Agric. Food Chem.
PUBLISHED: 12-03-2009
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Sesamin, a lignan from sesame oil, has been shown to have antihypertensive and antioxidative properties. This study examined the effects of sesamin on oxidized low-density lipoprotein (oxLDL)-induced endothelial dysfunction. Oxidative stress was determined by measuring the generation of intracellular reactive oxygen species (ROS) and by measuring the expression levels of superoxide dismutase (SOD) and endothelial nitric oxide synthase (eNOS). To assess the pro-inflammatory effects of oxLDL, ELISA was used to detect IL-8 expression, endothelin-1 (ET-1) secretion, and nuclear factor-kappaB (NF-kappaB) activation. The expression of adhesion molecules (ICAM-1, VCAM-1, and E-selectin) was examined by flow cytometry. In addition, several apoptotic signaling pathways were also investigated. The data showed that sesamin significantly ameliorated oxLDL-induced ROS generation and SOD-1 inactivation. Sesamin also attenuated the oxLDL-induced activation of NF-kappaB, suggesting that the inhibitory effects of sesamin on IL-8 and ET-1 release, adhesion molecule expression, and the adherence of THP-1 cells were at least partially through the blockade of NF-kappaB activation. Furthermore, sesamin attenuated oxLDL-induced apoptotic features, such as intracellular calcium accumulation and the subsequent collapse of mitochondrial membrane potential, release of cytochrome c, and activation of caspase-3. Results from this study may provide insight into possible molecular mechanisms underlying sesamins beneficial effects against oxLDL-mediated vascular endothelial dysfunction.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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